WorldWideScience

Sample records for actinidecarbon triple bonds

  1. AAA-DDD triple hydrogen bond complexes.

    Science.gov (United States)

    Blight, Barry A; Camara-Campos, Amaya; Djurdjevic, Smilja; Kaller, Martin; Leigh, David A; McMillan, Fiona M; McNab, Hamish; Slawin, Alexandra M Z

    2009-10-01

    Experiment and theory both suggest that the AAA-DDD pattern of hydrogen bond acceptors (A) and donors (D) is the arrangement of three contiguous hydrogen bonding centers that results in the strongest association between two species. Murray and Zimmerman prepared the first example of such a system (complex 3*2) and determined the lower limit of its association constant (K(a)) in CDCl(3) to be 10(5) M(-1) by (1)H NMR spectroscopy (Murray, T. J. and Zimmerman, S. C. J. Am. Chem. Soc. 1992, 114, 4010-4011). The first cationic AAA-DDD pair (3*4(+)) was described by Bell and Anslyn (Bell, D. A. and Anslyn, E. A. Tetrahedron 1995, 51, 7161-7172), with a K(a) > 5 x 10(5) M(-1) in CH(2)Cl(2) as determined by UV-vis spectroscopy. We were recently able to quantify the strength of a neutral AAA-DDD arrangement using a more chemically stable AAA-DDD system, 6*2, which has an association constant of 2 x 10(7) M(-1) in CH(2)Cl(2) (Djurdjevic, S., Leigh, D. A., McNab, H., Parsons, S., Teobaldi, G. and Zerbetto, F. J. Am. Chem. Soc. 2007, 129, 476-477). Here we report on further AA(A) and DDD partners, together with the first precise measurement of the association constant of a cationic AAA-DDD species. Complex 6*10(+)[B(3,5-(CF(3))(2)C(6)H(3))(4)(-)] has a K(a) = 3 x 10(10) M(-1) at RT in CH(2)Cl(2), by far the most strongly bound triple hydrogen bonded system measured to date. The X-ray crystal structure of 6*10(+) with a BPh(4)(-) counteranion shows a planar array of three short (NH...N distances 1.95-2.15 A), parallel (but staggered rather than strictly linear; N-H...N angles 165.4-168.8 degrees), primary hydrogen bonds. These are apparently reinforced, as theory predicts, by close electrostatic interactions (NH-*-N distances 2.78-3.29 A) between each proton and the acceptor atoms of the adjacent primary hydrogen bonds.

  2. Spectroscopic properties of the triple bond carotenoid alloxanthin

    Science.gov (United States)

    West, Robert; Keşan, Gürkan; Trsková, Eliška; Sobotka, Roman; Kaňa, Radek; Fuciman, Marcel; Polívka, Tomáš

    2016-06-01

    Alloxanthin, which has two triple bonds within its backbone, was studied by steady-state and femtosecond transient absorption spectroscopies. Alloxanthin demonstrates an S2 energy comparable to its non-triple bond homolog, zeaxanthin, while the S1 lifetime of 19 ps is markedly longer than that of zeaxanthin (9 ps). Along with corroborating quantum chemistry calculations, the results show that the long-lived S1 state of alloxanthin, which typically corresponds to the dynamic of a shorter carotenoid backbone, implies the triple bond isolates the conjugation of the backbone, increasing the S1 state energy and diminishing the S1-S2 energy gap.

  3. A literature review of actinide-carbonate mineral interactions

    Energy Technology Data Exchange (ETDEWEB)

    Stout, D.L. [Missouri Univ., Columbia, MO (United States). Dept. of Geological Sciences; Carroll, S.A. [Lawrence Livermore National Lab., CA (United States)

    1993-10-01

    Chemical retardation of actinides in groundwater systems is a potentially important mechanism for assessing the performance of the Waste Isolation Pilot Plant (WIPP), a facility intended to demonstrate safe disposal of transuranic waste. Rigorous estimation of chemical retardation during transport through the Culebra Dolomite, a water-bearing unit overlying the WIPP, requires a mechanistic understanding of chemical reactions between dissolved elements and mineral surfaces. This report represents a first step toward this goal by examining the literature for pertinent experimental studies of actinide-carbonate interactions. A summary of existing models is given, along with the types of experiments on which these models are based. Articles pertaining to research into actinide interactions with carbonate minerals are summarized. Select articles involving trace element-carbonate mineral interactions are also reviewed and may serve as templates for future research. A bibliography of related articles is included. Americium(III), and its nonradioactive analog neodymium(III), partition strongly from aqueous solutions into carbonate minerals. Recent thermodynamic, kinetic, and surface studies show that Nd is preferentially removed from solution, forming a Nd-Ca carbonate solid solution. Neptunium(V) is rapidly removed from solution by carbonates. Plutonium incorporation into carbonates is complicated by multiple oxidation states. Little research has been done on the radium(H) and thorium(IV) carbonate systems. Removal of uranyl ion from solution by calcite is limited to monolayer surface coverage.

  4. The Novel Selective Reduction of the C-C Triple Bond

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A novel reduction system is reported here in which the compounds with terminal C-C triple bond and disubstituted C-C triple bond react with NaBH4/Pd(PPh3)4 in a base condition and only terminal C-C triple bond is reduced.

  5. A Study of Secondary Ion Triple Bond Analogues.

    Science.gov (United States)

    1980-08-20

    into the formation of cluster ions have measured secondary energy spectra (35-42] and the effects of surface adsorbed gases on secondary yields [43,44...GeCI’ Cl:Ge 0.13 GaTe Te:GaP 0.1 SnAs a Sn:GaAs 0.08 SiBr+ Br:Si < 0.02 Sicl+ CI:Si < 0.01 SiSb- Sb:Si c GeAs As :Ge d Gap Ge: GaP e InSe - Se:InPh f... GaSe Se:GaAs f GeBr Br:Ge f GeSb Sb :Ge f SiAS Si: GaAs 9 a Not a triple bond analogue b ’to Ge detected, (signal < "cps) c Large SiSb- signal, implant

  6. The two faces of hydrogen-bond strength on triple AAA-DDD arrays.

    Science.gov (United States)

    Lopez, Alfredo Henrique Duarte; Caramori, Giovanni Finoto; Coimbra, Daniel Fernando; Parreira, Renato Luis Tame; da Silva, Éder Henrique

    2013-12-01

    Systems that are connected through multiple hydrogen bonds are the cornerstone of molecular recognition processes in biology, and they are increasingly being employed in supramolecular chemistry, specifically in molecular self-assembly processes. For this reason, the effects of different substituents (NO2, CN, F, Cl, Br, OCH3 and NH2) on the electronic structure, and consequently on the magnitude of hydrogen bonds in triple AAA-DDD arrays (A=acceptor, D=donor) were evaluated in the light of topological [electron localization function (ELF) and quantum theory of atoms in molecules (QTAIM)], energetic [Su-Li energy-decomposition analysis (EDA) and natural bond orbital analysis (NBO)], and geometrical analysis. The results based on local H-bond descriptors (geometries, QTAIM, ELF, and NBO) indicate that substitutions with electron-withdrawing groups on the AAA module tend to strengthen, whereas electron-donating substituents tend to weaken the covalent character of the AAA-DDD intermolecular H-bonds, and also indicate that the magnitude of the effect is dependent on the position of substitution. In contrast, Su-Li EDA results show an opposite behavior when compared to local H-bond descriptors, indicating that electron-donating substituents tend to increase the magnitude of H-bonds in AAA-DDD arrays, and thus suggesting that the use of local H-bond descriptors describes the nature of H bonds only partially, not providing enough insight about the strength of such H bonds.

  7. Molecularly Defined Nanostructures Based on a Novel AAA-DDD Triple Hydrogen-Bonding Motif.

    Science.gov (United States)

    Papmeyer, Marcus; Vuilleumier, Clément A; Pavan, Giovanni M; Zhurov, Konstantin O; Severin, Kay

    2016-01-26

    A facile and flexible method for the synthesis of a new AAA-DDD triple hydrogen-bonding motif is described. Polytopic supramolecular building blocks with precisely oriented AAA and DDD groups are thus accessible in few steps. These building blocks were used for the assembly of large macrocycles featuring four AAA-DDD interactions and a macrobicyclic complex with a total of six AAA-DDD interactions.

  8. Proposal of a new hydrogen-bonding form to maintain curdlan triple helix.

    Science.gov (United States)

    Miyoshi, Kentaro; Uezu, Kazuya; Sakurai, Kazuo; Shinkai, Seiji

    2004-06-01

    Curdlan and other beta-1,3-D-glucans form right-handed triple helices, and it has been believed that the intermolecular H-bond is present at the center of the helix to maintain the structure. In this H-bond model, three secondary OH groups form an inequilateral hexagonal shape perpendicular to the helix axis. This hexagonal form seems to be characteristic for beta-1,3-D-glucans and is widely accepted. We carried out MOPAC and ab initio calculations for the curdlan helix, and we propose a new intermolecular H-bonding model. In our model, the H-bonds are formed between the O2-atoms on different x-y planes along the curdlan helix, hence the H-bonds are not perpendicular to the helix axis. The new H-bonds are connected along the helix, traversing three curdlan chains to make a left-handed helix. Therefore, the H-bonding array leads to a reverse helix of the main chain. According to our MOPAC calculation, this model is more stable than the previous one. We believe that the continuous H-bonding array is stabilized by cooperative phenomena in the polymeric system.

  9. Quantification of the push-pull effect in substituted alkynes. Evaluation of +/-I/+/-M substituent effects in terms of C[triple bond]C bond length variation.

    Science.gov (United States)

    Kleinpeter, Erich; Frank, Andrea

    2009-06-18

    (13)C chemical shifts of alkynes, published to date, were computed at the DFT (B3LYP/6-311G*) level of theory and compared with the experimental delta values, and the agreement was employed as a measure of quality for the underlying structures. For the corresponding global minima structures, thus obtained, the occupation quotients of antibonding pi* and bonding pi orbitals (pi*(C[triple bond]C)/pi(C[triple bond]C)) and the bond lengths (d(C[triple bond]C)) of the central C[triple bond]C triple bond were computed and correlated to each other. The linear dependence obtained for the two push-pull parameters d(C[triple bond]C) and pi*(C[triple bond]C)/pi(C[triple bond]C) quantifies changes in the push-pull effect of substituents while deviations from the best line of fit indicate and ascertain quantitatively to what extend the inductive (+/-I) substituent effect changes with respect to the bond length of the C[triple bond]C triple bond.

  10. Di([5]trovacenyl)ethyne, di([5]trovacenyl)butadiyne, and di-1,4-([5]trovacenylethynyl)benzene: electrocommunication and magnetocommunication mediated by --C triple bond C--, --C triple bond C--C triple bond C-- and --C triple bond C--C6H4--C triple bond C-- spacers.

    Science.gov (United States)

    Elschenbroich, Christoph; Plackmeyer, Jörn; Nowotny, Mathias; Harms, Klaus; Pebler, Jürgen; Burghaus, Olaf

    2005-02-21

    The synthesis of dinuclear derivatives of trovacene (eta7-C7H7)V(eta5-C5H5) (1.) is reported, in which ethynyl (6..), butadiynyl (7..), and 1,4-di(ethynyl)phenyl (8..) groups serve as spacers between paramagnetic (S = 1/2) [5]trovacenyl units. The mononuclear precursors [5]trovacenylcarbaldehyde (2.) and [5]trovacenylacetylene (4.) are also described. Structural characterization by X-ray diffraction has been performed for 4., 6.., 7.., and 8.. Electronic communication as gleaned from cyclic voltammetry only manifests itself in the reduction processes where redox splitting deltaE1/2(0/ 1-, 1-/2-) is resolved for 6.. (deltaE1/2 = 150 mV) and indicated for 7.. (deltaE1/2 < or approximately 80 mV). Magnetocommunication leads to exchange coupling of the two electron spins which reside in vanadium centered orbitals. The values JEPR(6..) = (-)0.92, JEPR(7..) = (-)0.56, and JEPR(8..) = (-)0.005 cm(-1) are derived from the 51V hyperfine patterns. Accordingly, attenuation of exchange interaction by oligoalkyne spacers is weak, corresponding to a factor of 0.6 only per added --C triple bond C-- unit. In the determination of very weak long distance exchange interactions, EPR excels because of the range 5 x 10(-4) < or approximately J < or approximately 1.5 cm(-1) accessible in the case of 51V as a reporting magnetic nucleus and because competing intermolecular exchange is quenched in dilute fluid solution. This is demonstrated by the value Jchi(7..) = -3.84 cm(-1) obtained from a magnetic susceptibility study, which exceeds JEPR(7..) by a factor of 7. The small magnitude of spin exchange interaction between trovacene units reflects the fact that the spin bearing V3dz2 orbital is virtually orthogonal to the pi-perimeter ligand orbitals and weakly overlapping only with the a1g(sigma) ring orbitals, creating two bottlenecks for spin-exchange in the spacer-containing ditrovacenes.

  11. Effect of irrigation technique for removal of triple antibiotic paste on bond strength of MTA to root dentin.

    Science.gov (United States)

    Dumani, Aysin; Yilmaz, Sehnaz; Yoldas, Oguz; Bek, Zeliha Gonca

    2016-01-01

    This study evaluated the bond strength of mineral trioxide aggregate (MTA) to root canal dentin after the performance of various irrigation procedures to remove triple antibiotic paste (TAP). A total of 56 single-rooted human mandibular premolars were instrumented using a rotary system to size 40 and divided randomly into a control group (no intracanal dressing) and three experimental groups (TAP application for 28 days). TAP was then removed by rinsing with 10 mL 2.5% NaOCl using three irrigation systems (Vibringe sonic irrigation, CanalBrush, and syringe irrigation). The coronal and middle parts of root canals were then obturated with MTA. After storage for 1 week, each specimen was embedded in an acrylic block and sectioned horizontally (2-mm-thick slices) at two levels (coronal and middle). Bond strength of MTA to root canal dentin was assessed in 28 samples per group via push-out test using a universal testing machine. Data from the four groups were compared using one-way analysis of variance. Tukey's test was used for multiple comparisons. Push-out bond strength values were significantly higher in the control and Vibringe groups than in the CanalBrush and syringe irrigation groups (p irrigation system may increase the push-out bond strength of MTA compared with the use of the CanalBrush or syringe irrigation.

  12. Calculation of activation energies for hydrogen-atom abstractions by radicals containing carbon triple bonds

    Science.gov (United States)

    Brown, R. L.; Laufer, A. H.

    1981-01-01

    Activation energies are calculated by the bond-energy-bond-order (BEBO) and the bond-strength-bond-length (BSBL) methods for the reactions of C2H radicals with H2, CH4, and C2H6 and for the reactions of CN radicals with H2 and CH4. The BSBL technique accurately predicts the activation energies for these reactions while the BEBO method yields energies averaging 9 kcal higher than those observed. A possible reason for the disagreement is considered.

  13. Structural information from OH-stretching vibrations—XIV. The influence of local interactions on the OH-stretching frequency in alcohols with an α-triple bond

    NARCIS (Netherlands)

    Visser, T.; Maas, J.H. van der

    1984-01-01

    The effect on the OH-stretching vibration of changes in the π-character of alcohols with an α-triple bond has been studied by means of the i.r. absorption band. It is demonstrated that in the investigated alcohols the OH … π interaction causes an increase of the OH-frequency as a result of the posit

  14. Photochromic organometallics with a dithienylethene (DTE) Bridge, [Y-C[triple bond]C-DTE-C[triple bond]C-Y] (Y={MCp*(dppe)}): photoswitchable molecular wire (M=Fe) versus dual photo- and electrochromism (M=Ru).

    Science.gov (United States)

    Tanaka, Yuya; Ishisaka, Takuya; Inagaki, Akiko; Koike, Takashi; Lapinte, Claude; Akita, Munetaka

    2010-04-26

    Dinuclear acetylide-type complexes bridged by a photochromic dithienylethene unit (DTE), [Y-C[triple bond]C-DTE-C[triple bond]C-Y] 1 (Y={MCp*(dppe)}; Cp*=pentamethylcyclopentadienyl, M=Fe (1(Fe)), Ru (1(Ru))), have been prepared, and their wirelike and switching behavior, as well as their oxidation chemistry has been investigated. The DTE complexes 1 exhibit photochromic behavior in a manner similar to organic DTE derivatives; UV irradiation causes ring closure of the open isomer 1O to form the closed isomer 1C and visible-light irradiation of the resultant 1C causes reverse ring opening to regenerate 1O. But the performance is dependent on the metals. With respect to the interconversion rates and the 1C content at the photostationary state under UV irradiation, the ruthenium complex 1(Ru) is superior to the iron analogue 1(Fe). The wirelike performance is associated with the photochromic processes, and the efficient switching performance has been verified for 1(Fe) as characterized by the V(ab) values [V(ab) is the electronic coupling derived from intervalence charge-transfer (IVCT) bands: V(ab)(1(Fe)C; ON)=0.047 eV versus V(ab)(1(Fe)O; OFF)=0 eV], and are also supported by the large switching factor (SF=K(C)(C; ON)/K(C)(O; OFF)=39; K(C)=comproportionation constant). SF for 1(Ru) is determined to be 4.2. The remarkable switching behavior arises from the different pi-conjugated systems in the two isomeric forms, that is, cross-conjugated (1O) and fully conjugated pi-systems (1C). It was also found that, in contrast to the reversible redox behavior of the iron complex 1(Fe), the ruthenium complex 1(Ru)O undergoes oxidative ring closure to form the dicationic species of the closed isomer 1(Ru)C(2+) and, thus, the ruthenium system 1(Ru) shows dual photo- and electrochromism. The distinct oxidation behavior of 1(Fe) and 1(Ru) can be ascribed to the spin distribution on the diradical intermediates 1(Fe)O(2+) and 1(Ru)O(2+), as supported by DFT calculations.

  15. Synthesis of Biotin Linkers with the Activated Triple Bond Donor [p-(N-propynoylaminotoluic Acid] (PATA for Efficient Biotinylation of Peptides and Oligonucleotides

    Directory of Open Access Journals (Sweden)

    Martina Jezowska

    2012-11-01

    Full Text Available Biotin is an important molecule for modern biological studies including, e.g., cellular transport. Its exclusive affinity to fluorescent streptavidin/avidin proteins allows ready and specific detection. As a consequence methods for the attachment of biotin to various biological targets are of high importance, especially when they are very selective and can also proceed in water. One useful method is Hüisgen dipolar [3+2]-cycloaddition, commonly referred to as “click chemistry”. As we reported recently, the activated triple bond donor p-(N-propynoylaminotoluic acid (PATA gives excellent results when used for conjugations at submicromolar concentrations. Thus, we have designed and synthesized two biotin linkers, with different lengths equipped with this activated triple bond donor and we proceeded with biotinylation of oligonucleotides and C-myc peptide both in solution and on solid support with excellent yields of conversion.

  16. Photoinduced Processes of Supramolecular Nanoarrays Composed of Porphyrin and Benzo[ghi]perylenetriimide Units through Triple Hydrogen Bonds with One-Dimensional Columnar Phases.

    Science.gov (United States)

    Sakai, Hayato; Ohkubo, Kei; Fukuzumi, Shunichi; Hasobe, Taku

    2016-02-18

    One-dimensional supramolecular columnar phases composed of porphyrins (electron donor: D) and benzo[ghi]perylenetriimides (electron acceptor: A) through triple hydrogen bonds have been successfully constructed to perform sequential light-harvesting and electron-transfer processes. A series of benzo[ghi]peryleneimide derivatives have been synthesized to examine the substituent effects such as imide and nitrile groups on the spectroscopic and electrochemical properties. Then, formation of the 1:1 supramolecular complex between zinc porphyrin and benzo[ghi]perylenetriimide derivatives through triple hydrogen bonds was confirmed by Job's plot of (1) H NMR titration. Next, the one-dimensional supramolecular nanoarrays were successfully prepared in a mixed solvent. X-ray diffraction (XRD) measurement suggested that these nanoarrays contained one-dimensional columnar phases composed of stacked donor and acceptor layers. Finally, femtosecond transient absorption and electron spin resonance (ESR) measurements clearly indicated that photoinduced electron transfer occurred via the singlet excited states in the supramolecular columns.

  17. Investigation of room-temperature wafer bonded GaInP/GaAs/InGaAsP triple-junction solar cells

    Science.gov (United States)

    Yang, Wen-xian; Dai, Pan; Ji, Lian; Tan, Ming; Wu, Yuan-yuan; Uchida, Shiro; Lu, Shu-long; Yang, Hui

    2016-12-01

    We report on the fabrication of III-V compound semiconductor multi-junction solar cells using the room-temperature wafer bonding technique. GaInP/GaAs dual-junction solar cells on GaAs substrate and InGaAsP single junction solar cell on InP substrate were separately grown by all-solid state molecular beam epitaxy (MBE). The two cells were then bonded to a triple-junction solar cell at room-temperature. A conversion efficiency of 30.3% of GaInP/GaAs/InGaAsP wafer-bonded solar cell was obtained at 1-sun condition under the AM1.5G solar simulator. The result suggests that the room-temperature wafer bonding technique and MBE technique have a great potential to improve the performance of multi-junction solar cell.

  18. The Nature of the Idealized Triple Bonds Between Principal Elements and the σ Origins of Trans-Bent Geometries-A Valence Bond Study.

    Science.gov (United States)

    Ploshnik, Elina; Danovich, David; Hiberty, Philippe C; Shaik, Sason

    2011-04-12

    We describe herein a valence bond (VB) study of 27 triply bonded molecules of the general type X≡Y, where X and Y are main element atoms/fragments from groups 13-15 in the periodic table. The following conclusions were derived from the computational data: (a) Single π-bond and double π-bond energies for the entire set correlate with the "molecular electronegativity", which is the sum of the X and Y electronegativites for X≡Y. The correlation with the molecular electronegativity establishes a simple rule of periodicity: π-bonding strength generally increases from left to right in a period and decreases down a column in the periodic table. (b) The σ frame invariably prefers trans bending, while π-bonding gets destabilized and opposes the trans distortion. In HC≡CH, the π-bonding destabilization overrides the propensity of the σ frame to distort, while in the higher row molecules, the σ frame wins out and establishes trans-bent molecules with 2(1)/2 bonds, in accord with recent experimental evidence based on solid state (29)Si NMR of the Sekiguchi compound. Thus, in the trans-bent molecules "less bonds pay more". (c) All of the π bonds show significant bonding contributions from the resonance energy due to covalent-ionic mixing. This quantity is shown to correlate linearly with the corresponding "molecular electronegativity" and to reflect the mechanism required to satisfy the equilibrium condition for the bond. The π bonds for molecules possessing high molecular electronegativity are charge-shift bonds, wherein bonding is dominated by the resonance energy of the covalent and ionic forms, rather than by either form by itself.

  19. Asymmetry in the triple helix of collagen-like heterotrimers confirms that external bonds stabilize collagen structure.

    Science.gov (United States)

    Slatter, David A; Miles, Christopher A; Bailey, Allen J

    2003-05-23

    Heating and subsequent cooling mixtures of (Pro-Pro-Gly)(10) and (Pro-Hyp-Gly)(10) peptides leads to formation of model heterotrimeric collagen helices that can be isolated by HPLC. These heterotrimeric collagen peptide helices are shown to be fundamentally unstable as denaturing then renaturing experiments result in heterotrimeric/homotrimeric mixtures. As the proportion of hydroxyproline-containing chains in the trimers increases, differential scanning calorimetry shows that the helix melting temperatures and denaturation enthalpies increasing non-linearly. Three types of Rich-Crick hydrogen bonds observed by NMR allow modelling of heterotrimeric structures based on published homotrimeric X-ray data. This revealed a small axial movement of (Pro-Hyp-Gly)(10) chains towards the C-terminal of the helix, demonstrating heterotrimeric asymmetry.

  20. Thioamides in the collagen triple helix.

    Science.gov (United States)

    Newberry, Robert W; VanVeller, Brett; Raines, Ronald T

    2015-06-14

    To probe noncovalent interactions within the collagen triple helix, backbone amides were replaced with a thioamide isostere. This subtle substitution is the first in the collagen backbone that does not compromise thermostability. A triple helix with a thioamide as a hydrogen bond donor was found to be more stable than triple helices assembled from isomeric thiopeptides.

  1. Exponential triples

    CERN Document Server

    Sisto, Alessandro

    2011-01-01

    Using ultrafilter techniques we show that in any partition of $\\mathbb{N}$ into 2 cells there is one cell containing infinitely many exponential triples, i.e. triples of the kind $a,b,a^b$ (with $a,b>1$). Also, we will show that any multiplicative $IP^*$ set is an "exponential $IP$ set", the analogue of an $IP$ set with respect to exponentiation.

  2. Energetics of the O-H bond and of intramolecular hydrogen bonding in HOC6H4C(O)Y (Y = H, CH3, CH2CH=CH2, C[triple bond]CH, CH2F, NH2, NHCH3, NO2, OH, OCH3, OCN, CN, F, Cl, SH, and SCH3) compounds.

    Science.gov (United States)

    Bernardes, Carlos E S; Minas da Piedade, Manuel E

    2008-10-09

    The energetics of the phenolic O-H bond in a series of 2- and 4-HOC 6H 4C(O)Y (Y = H, CH3, CH 2CH=CH2, C[triple bond]CH, CH2F, NH2, NHCH 3, NO2, OH, OCH3, OCN, CN, F, Cl, SH, and SCH3) compounds and of the intramolecular O...H hydrogen bond in 2-HOC 6H 4C(O)Y, was investigated by using a combination of experimental and theoretical methods. The standard molar enthalpies of formation of 2-hydroxybenzaldehyde (2HBA), 4-hydroxybenzaldehyde (4HBA), 2'-hydroxyacetophenone (2HAP), 2-hydroxybenzamide (2HBM), and 4-hydroxybenzamide (4HBM), at 298.15 K, were determined by micro- or macrocombustion calorimetry. The corresponding enthalpies of vaporization or sublimation were also measured by Calvet drop-calorimetry and Knudsen effusion measurements. The combination of the obtained experimental data led to Delta f H m (o)(2HBA, g) = -238.3 +/- 2.5 kJ.mol (-1), DeltafHm(o)(4HBA, g) = -220.3 +/- 2.0 kJ.mol(-1), Delta f H m (o)(2HAP, g) = -291.8 +/- 2.1 kJ.mol(-1), DeltafHm(o)(2HBM, g) = -304.8 +/- 1.5 kJ.mol (-1), and DeltafHm(o) (4HBM, g) = -278.4 +/- 2.4 kJ.mol (-1). These values, were used to assess the predictions of the B3LYP/6-31G(d,p), B3LYP/6-311+G(d,p), B3LYP/aug-cc-pVDZ, B3P86/6-31G(d,p), B3P86/6-311+G(d,p), B3P86/aug-cc-pVDZ, and CBS-QB3 methods, for the enthalpies of a series of isodesmic gas phase reactions. In general, the CBS-QB3 method was able to reproduce the experimental enthalpies of reaction within their uncertainties. The B3LYP/6-311+G(d,p) method, with a slightly poorer accuracy than the CBS-QB3 approach, achieved the best performance of the tested DFT models. It was further used to analyze the trends of the intramolecular O...H hydrogen bond in 2-HOC 6H 4C(O)Y evaluated by the ortho-para method and to compare the energetics of the phenolic O-H bond in 2- and 4-HOC 6H 4C(O)Y compounds. It was concluded that the O-H bond "strength" is systematically larger for 2-hydroxybenzoyl than for the corresponding 4-hydroxybenzoyl isomers mainly due to the presence of

  3. The samurai bond market

    OpenAIRE

    1997-01-01

    Issuance in the samurai bond market has more than tripled over the past several years. Some observers have attributed this growth to a systematic underestimation of credit risk in the market. A detailed review of credit quality, ratings differences, and initial issue pricing in the samurai bond market, however, turns up little evidence to support this concern.

  4. Molecular structure of the collagen triple helix.

    Science.gov (United States)

    Brodsky, Barbara; Persikov, Anton V

    2005-01-01

    The molecular conformation of the collagen triple helix confers strict amino acid sequence constraints, requiring a (Gly-X-Y)(n) repeating pattern and a high content of imino acids. The increasing family of collagens and proteins with collagenous domains shows the collagen triple helix to be a basic motif adaptable to a range of proteins and functions. Its rodlike domain has the potential for various modes of self-association and the capacity to bind receptors, other proteins, GAGs, and nucleic acids. High-resolution crystal structures obtained for collagen model peptides confirm the supercoiled triple helix conformation, and provide new information on hydrogen bonding patterns, hydration, sidechain interactions, and ligand binding. For several peptides, the helix twist was found to be sequence dependent, and such variation in helix twist may serve as recognition features or to orient the triple helix for binding. Mutations in the collagen triple-helix domain lead to a variety of human disorders. The most common mutations are single-base substitutions that lead to the replacement of one Gly residue, breaking the Gly-X-Y repeating pattern. A single Gly substitution destabilizes the triple helix through a local disruption in hydrogen bonding and produces a discontinuity in the register of the helix. Molecular information about the collagen triple helix and the effect of mutations will lead to a better understanding of function and pathology.

  5. Photoswitchable triple hydrogen-bonding motif.

    Science.gov (United States)

    Herder, Martin; Pätzel, Michael; Grubert, Lutz; Hecht, Stefan

    2011-01-07

    Photochromic bis(thiazol-4-yl)maleimides, displaying enhanced binding affinity to complementary melamine receptors in their ring-closed switching state, have been developed and could pave the way to light-responsive supramolecular assemblies.

  6. Effects of chain length and Au spin-orbit coupling on 3(pi pi*) emission from bridging Cn2- units: theoretical characterization of spin-forbidden radiative transitions in metal-capped one-dimensional carbon chains [H3PAu(C[triple bond]C)nAuPH3].

    Science.gov (United States)

    Cao, Zexing; Zhang, Qianer

    2004-04-19

    Density functional theory and CASSCF calculations have been used to optimize the geometries of binuclear gold(I) complexes [H(3)PAu(C[triple bond]C)(n)AuPH(3)] (n=1-6) in their ground states and selected lowest energy (3)(pi pi*) excited states. Vertical excitation energies obtained by time-dependent density functional calculations for the spin-forbidden singlet-triplet transitions have exponential-decay size dependence. The predicted singlet-triplet splitting limit of [H(3)PAu(C[triple bond]C)(proportional/variant)AuPH(3)] is about 8317 cm(-1). Calculated singlet-triplet transition energies are in reasonable agreement with available experimental observations. The effect of the heavy atom Au spin-orbit coupling on the (3)(pi pi*) emission of these metal-capped one-dimensional carbon allotropes has been investigated by MRCI calculations. The contribution of the spin- and dipole-allowed singlet excited state to the spin-orbit-coupling wave function of the (3)(pi pi*) excited state makes the low-lying acetylenic triplet excited states become sufficiently allowed so as to appear in both electronic absorption and emission.

  7. Equilibrium CO bond lengths

    Science.gov (United States)

    Demaison, Jean; Császár, Attila G.

    2012-09-01

    Based on a sample of 38 molecules, 47 accurate equilibrium CO bond lengths have been collected and analyzed. These ultimate experimental (reEX), semiexperimental (reSE), and Born-Oppenheimer (reBO) equilibrium structures are compared to reBO estimates from two lower-level techniques of electronic structure theory, MP2(FC)/cc-pVQZ and B3LYP/6-311+G(3df,2pd). A linear relationship is found between the best equilibrium bond lengths and their MP2 or B3LYP estimates. These (and similar) linear relationships permit to estimate the CO bond length with an accuracy of 0.002 Å within the full range of 1.10-1.43 Å, corresponding to single, double, and triple CO bonds, for a large number of molecules. The variation of the CO bond length is qualitatively explained using the Atoms in Molecules method. In particular, a nice correlation is found between the CO bond length and the bond critical point density and it appears that the CO bond is at the same time covalent and ionic. Conditions which permit the computation of an accurate ab initio Born-Oppenheimer equilibrium structure are discussed. In particular, the core-core and core-valence correlation is investigated and it is shown to roughly increase with the bond length.

  8. A class of luminescent cyclometalated alkynylgold(III) complexes: synthesis, characterization, and electrochemical, photophysical, and computational studies of [Au(C=N=C)(C triple bond C-R)] (C=N=C = kappa(3)C,N,C bis-cyclometalated 2,6-diphenylpyridyl).

    Science.gov (United States)

    Wong, Keith Man-Chung; Hung, Ling-Ling; Lam, Wai Han; Zhu, Nianyong; Yam, Vivian Wing-Wah

    2007-04-11

    A new class of luminescent cyclometalated alkynylgold(III) complexes, [Au(RC=N(R')=CR)(CCR' ')], i.e., [Au(C=N=C)(C triple bond CR'')] (HC=N=CH = 2,6-diphenylpyridine) R' ' = C6H5 1, C6H4-Cl-p 2, C6H4-NO2-p 3, C6H4-OCH3-p 4, C6H4-NH2-p 5, C6H4-C6H13-p 6, C6H13 7, [Au(tBuC=N=CtBu)(C triple bond CC6H5)] 8 (HtBuC=N=CtBuH = 2,6-bis(4-tert-butylphenyl)pyridine), and [Au(C=NTol=C)(CCC6H4-C6H13-p)] 9 (HC=NTol=CH = 2,6-diphenyl-4-p-tolylpyridine), have been synthesized and characterized. The X-ray crystal structures of most of the complexes have also been determined. Electrochemical studies show that, in general, the first oxidation wave is an alkynyl ligand-centered oxidation, while the first reduction couple is ascribed to a ligand-centered reduction of the cyclometalated ligand with the exception of 3 in which the first reduction couple is assigned as an alkynyl ligand-centered reduction. Their electronic absorption and luminescence behaviors have also been investigated. In dichloromethane solution at room temperature, the low-energy absorption bands are assigned as the pi-pi* intraligand (IL) transition of the cyclometalated RC=N(R')=CR ligand with some mixing of a [pi(C triple bond CR'') --> pi*(RC=N(R')=CR)] ligand-to-ligand charge transfer (LLCT) character. The low-energy emission bands of all the complexes, with the exception of 5, are ascribed to origins mainly derived from the pi-pi* IL transition of the cyclometalated RC=N(R')=CR ligand. In the case of 5 that contains an electron-rich amino substituent on the alkynyl ligand, the low-energy emission band was found to show an obvious shift to the red. A change in the origin of emission is evident, and the emission of 5 is tentatively ascribed to a [pi(CCC6H4NH2) --> pi*(C=N=C)] LLCT excited-state origin. DFT and TDDFT computational studies have been performed to verify and elucidate the results of the electrochemical and photophysical studies.

  9. Temporal Lorentzian spectral triples

    Science.gov (United States)

    Franco, Nicolas

    2014-09-01

    We present the notion of temporal Lorentzian spectral triple which is an extension of the notion of pseudo-Riemannian spectral triple with a way to ensure that the signature of the metric is Lorentzian. A temporal Lorentzian spectral triple corresponds to a specific 3 + 1 decomposition of a possibly noncommutative Lorentzian space. This structure introduces a notion of global time in noncommutative geometry. As an example, we construct a temporal Lorentzian spectral triple over a Moyal-Minkowski spacetime. We show that, when time is commutative, the algebra can be extended to unbounded elements. Using such an extension, it is possible to define a Lorentzian distance formula between pure states with a well-defined noncommutative formulation.

  10. A statistically derived parameterization for the collagen triple-helix.

    Science.gov (United States)

    Rainey, Jan K; Goh, M Cynthia

    2002-11-01

    The triple-helix is a unique secondary structural motif found primarily within the collagens. In collagen, it is a homo- or hetero-tripeptide with a repeating primary sequence of (Gly-X-Y)(n), displaying characteristic peptide backbone dihedral angles. Studies of bulk collagen fibrils indicate that the triple-helix must be a highly repetitive secondary structure, with very specific constraints. Primary sequence analysis shows that most collagen molecules are primarily triple-helical; however, no high-resolution structure of any entire protein is yet available. Given the drastic morphological differences in self-assembled collagen structures with subtle changes in assembly conditions, a detailed knowledge of the relative locations of charged and sterically bulky residues in collagen is desirable. Its repetitive primary sequence and highly conserved secondary structure make collagen, and the triple-helix in general, an ideal candidate for a general parameterization for prediction of residue locations and for the use of a helical wheel in the prediction of residue orientation. Herein, a statistical analysis of the currently available high-resolution X-ray crystal structures of model triple-helical peptides is performed to produce an experimentally based parameter set for predicting peptide backbone and C(beta) atom locations for the triple-helix. Unlike existing homology models, this allows easy prediction of an entire triple-helix structure based on all existing high-resolution triple-helix structures, rather than only on a single structure or on idealized parameters. Furthermore, regional differences based on the helical propensity of residues may be readily incorporated. The parameter set is validated in terms of the predicted bond lengths, backbone dihedral angles, and interchain hydrogen bonding.

  11. Pythagorean Triples from Harmonic Sequences.

    Science.gov (United States)

    DiDomenico, Angelo S.; Tanner, Randy J.

    2001-01-01

    Shows how all primitive Pythagorean triples can be generated from harmonic sequences. Use inductive and deductive reasoning to explore how Pythagorean triples are connected with another area of mathematics. (KHR)

  12. Constructing Models in Teaching of Chemical Bonds: Ionic Bond, Covalent Bond, Double and Triple Bonds, Hydrogen Bond and Molecular Geometry

    Science.gov (United States)

    Uce, Musa

    2015-01-01

    Studies in chemistry education show that chemistry topics are considered as abstract, complicated and hard to understand by students. For this reason, it is important to develop new materials and use them in classes for better understanding of abstract concepts. Moving from this point, a student-centered research guided by a teacher was conducted…

  13. Structural, spectroscopic, and multiconfigurational quantum chemical investigations of the electron-rich metal-metal triple-bonded Tc(2)X(4)(PMe(3))(4) (X = Cl, Br) complexes.

    Science.gov (United States)

    Poineau, Frederic; Forster, Paul M; Todorova, Tanya K; Gagliardi, Laura; Sattelberger, Alfred P; Czerwinski, Kenneth R

    2010-07-19

    The compounds Tc(2)Cl(4)(PMe(3))(4) and Tc(2)Br(4)(PMe(3))(4) were formed from the reaction between (n-Bu(4)N)(2)Tc(2)X(8) (X = Cl, Br) and trimethylphosphine. The Tc(II) dinuclear species were characterized by single-crystal XRD, UV-visible spectroscopy, and cyclic voltammetry techniques, and the results are compared to those obtained from density functional theory and multiconfigurational (CASSCF/CASPT2) quantum chemical studies. The compound Tc(2)Cl(4)(PMe(3))(4) crystallizes in the monoclinic space group C2/c [a = 17.9995(9) A, b = 9.1821(5) A, c = 17.0090(9) A, beta = 115.4530(10) degrees ] and is isostructural to M(2)Cl(4)(PMe(3))(4) (M = Re, Mo, W) and to Tc(2)Br(4)(PMe(3))(4). The metal-metal distance (2.1318(2) A) is similar to the one found in Tc(2)Br(4)(PMe(3))(4) (2.1316(5) A). The calculated molecular structures of the ground states are in excellent agreement with the structures determined experimentally. Calculations of effective bond orders for Tc(2)X(8)(2-) and Tc(2)X(4)(PMe(3))(4) (X = Cl, Br) indicate stronger pi bonds in the Tc(2)(4+) core than in Tc(2)(6+) core. The electronic spectra were recorded in benzene and show a series of low intensity bands in the range 10 000-26 000 cm(-1). Assignment of the bands as well as computing their excitation energies and intensities were performed at both TD-DFT and CASSCF/CASPT2 levels of theory. Calculations predict that the lowest energy band corresponds to the delta* --> sigma* transition, the difference between calculated and experimental values being 228 cm(-1) for X = Cl and 866 cm(-1) for X = Br. The next bands are attributed to delta* --> pi*, delta --> sigma*, and delta --> pi* transitions. The cyclic voltammograms exhibit two reversible waves and indicate that Tc(2)Br(4)(PMe(3))(4) exhibits more positive oxidation potentials than Tc(2)Cl(4)(PMe(3))(4.) This phenomenon is discussed and ascribed to stronger metal (d) to halide (d) back bonding in the bromo complex. Further analysis indicates that Tc

  14. PbCNN: A molecule containing Pb≡C bonding

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    In order to predict potential molecules with Pb≡C bonding, we investigated the potential energy sur-face of a tetra-atomic system [PbCN2] at the CCSD(T)//B3LYP level. We found that the linear isomer PbCNN possesses good thermodynamic and kinetic stability. The combined molecular orbital analysis, hydrogenation heat, bond energy and bond dissociation energy all proved that PbCNN is composed of Pb≡ C triple bonding.

  15. PbCNN: A molecule containing Pb≡C bonding

    Institute of Scientific and Technical Information of China (English)

    ZHANG Wen-Bin; SHI Guo-Sheng; DING Yi-Hong; SUN Chia-Chung

    2009-01-01

    In order to predict potential molecules with Pb≡C bonding, we investigated the potential energy sur-face of a tetra-atomic system [PbCN2] at the CCSD(T)//B3LYP level. We found that the linear isomer PbCNN possesses good thermodynamic and kinetic stability. The combined molecular orbital analysis, hydrogenation heat, bond energy and bond dissociation energy all proved that PbCNN is composed of Pb≡C triple bonding.

  16. Bond Issues.

    Science.gov (United States)

    Pollack, Rachel H.

    2000-01-01

    Notes trends toward increased borrowing by colleges and universities and offers guidelines for institutions that are considering issuing bonds to raise money for capital projects. Discussion covers advantages of using bond financing, how use of bonds impacts on traditional fund raising, other cautions and concerns, and some troubling aspects of…

  17. Intramolecular triple helix as a model for regular polyribonucleotide (CAA)(n).

    Science.gov (United States)

    Efimov, Alexander V; Spirin, Alexander S

    2009-10-09

    The regular (CAA)(n) polyribonucleotide, as well as the omega leader sequence containing (CAA)-rich core, have recently been shown to form cooperatively melted and compact structures. In this report, we propose a structural model for the (CAA)(n) sequence in which the polyribonucleotide chain is folded upon itself, so that it forms an intramolecular triple helix. The triple helix is stabilized by hydrogen bonding between bases thus forming coplanar triads, and by stacking interactions between the base triads. A distinctive feature of the proposed triple helix is that it does not contain the canonical double-helix elements. The difference from the known triple helices is that Watson-Crick hydrogen bond pairings do not take place in the interactions between the bases within the base triads.

  18. Polyproline and triple helix motifs in host-pathogen recognition.

    Science.gov (United States)

    Berisio, Rita; Vitagliano, Luigi

    2012-12-01

    Secondary structure elements often mediate protein-protein interactions. Despite their low abundance in folded proteins, polyproline II (PPII) and its variant, the triple helix, are frequently involved in protein-protein interactions, likely due to their peculiar propensity to be solvent-exposed. We here review the role of PPII and triple helix in mediating hostpathogen interactions, with a particular emphasis to the structural aspects of these processes. After a brief description of the basic structural features of these elements, examples of host-pathogen interactions involving these motifs are illustrated. Literature data suggest that the role played by PPII motif in these processes is twofold. Indeed, PPII regions may directly mediate interactions between proteins of the host and the pathogen. Alternatively, PPII may act as structural spacers needed for the correct positioning of the elements needed for adhesion and infectivity. Recent investigations have highlighted that collagen triple helix is also a common target for bacterial adhesins. Although structural data on complexes between adhesins and collagen models are rather limited, experimental and theoretical studies have unveiled some interesting clues of the recognition process. Interestingly, very recent data show that not only is the triple helix used by pathogens as a target in the host-pathogen interaction but it may also act as a bait in these processes since bacterial proteins containing triple helix regions have been shown to interact with host proteins. As both PPII and triple helix expose several main chain non-satisfied hydrogen bond acceptors and donors, both elements are highly solvated. The preservation of the solvation state of both PPII and triple helix upon protein-protein interaction is an emerging aspect that will be here thoroughly discussed.

  19. Collagenolytic Matrix Metalloproteinase Activities toward Peptomeric Triple-Helical Substrates.

    Science.gov (United States)

    Stawikowski, Maciej J; Stawikowska, Roma; Fields, Gregg B

    2015-05-19

    Although collagenolytic matrix metalloproteinases (MMPs) possess common domain organizations, there are subtle differences in their processing of collagenous triple-helical substrates. In this study, we have incorporated peptoid residues into collagen model triple-helical peptides and examined MMP activities toward these peptomeric chimeras. Several different peptoid residues were incorporated into triple-helical substrates at subsites P3, P1, P1', and P10' individually or in combination, and the effects of the peptoid residues were evaluated on the activities of full-length MMP-1, MMP-8, MMP-13, and MMP-14/MT1-MMP. Most peptomers showed little discrimination between MMPs. However, a peptomer containing N-methyl Gly (sarcosine) in the P1' subsite and N-isobutyl Gly (NLeu) in the P10' subsite was hydrolyzed efficiently only by MMP-13 [nomenclature relative to the α1(I)772-786 sequence]. Cleavage site analysis showed hydrolysis at the Gly-Gln bond, indicating a shifted binding of the triple helix compared to the parent sequence. Favorable hydrolysis by MMP-13 was not due to sequence specificity or instability of the substrate triple helix but rather was based on the specific interactions of the P7' peptoid residue with the MMP-13 hemopexin-like domain. A fluorescence resonance energy transfer triple-helical peptomer was constructed and found to be readily processed by MMP-13, not cleaved by MMP-1 and MMP-8, and weakly hydrolyzed by MT1-MMP. The influence of the triple-helical structure containing peptoid residues on the interaction between MMP subsites and individual substrate residues may provide additional information about the mechanism of collagenolysis, the understanding of collagen specificity, and the design of selective MMP probes.

  20. Triple-resonant transducers.

    Science.gov (United States)

    Butler, Stephen C

    2012-06-01

    A detailed analysis is presented of two novel multiple-resonant transducers which produce a wider transmit response than that of a conventional Tonpilz-type transducer. These multi-resonant transducers are Tonpilz-type longitudinal vibrators that produce three coupled resonances and are referred to as triple-resonant transducers (TRTs). One of these designs is a mechanical series arrangement of a tail mass, piezoelectric ceramic stack, central mass, compliant spring, second central mass, second compliant spring, and a piston-radiating head mass. The other TRT design is a mechanical series arrangement of a tail mass, piezoelectric ceramic stack, central mass, compliant spring, and head mass with a quarter-wave matching layer of poly(methyl methacrylate) on the head mass. Several prototype transducer element designs were fabricated that demonstrated proof-of-concept.

  1. Harmonic analysis on triple spaces

    DEFF Research Database (Denmark)

    Danielsen, Thomas Hjortgaard

    In this thesis we study examples of triple spaces, both their structure theory, their invariant differential operators as well as analysis on them. The first major results provide us with some examples of triple spaces which are strongly spherical, i.e. satisfy some conditions reminiscent...... of properties of symmetric spaces. The algebras of invariant differential operators for these spaces are studied and the conclusion is that most of them are non-commutative. Finally, we restrict our attention to a single triple space, giving a specific polar decomposition and corresponding integration formula......, and studying the relations between open orbits of parabolic subgroups, multiplicities and distribution vectors....

  2. Parental Bonding

    Directory of Open Access Journals (Sweden)

    T. Paul de Cock

    2014-08-01

    Full Text Available Estimating the early parent–child bonding relationship can be valuable in research and practice. Retrospective dimensional measures of parental bonding provide a means for assessing the experience of the early parent–child relationship. However, combinations of dimensional scores may provide information that is not readily captured with a dimensional approach. This study was designed to assess the presence of homogeneous groups in the population with similar profiles on parental bonding dimensions. Using a short version of the Parental Bonding Instrument (PBI, three parental bonding dimensions (care, authoritarianism, and overprotection were used to assess the presence of unobserved groups in the population using latent profile analysis. The class solutions were regressed on 23 covariates (demographics, parental psychopathology, loss events, and childhood contextual factors to assess the validity of the class solution. The results indicated four distinct profiles of parental bonding for fathers as well as mothers. Parental bonding profiles were significantly associated with a broad range of covariates. This person-centered approach to parental bonding has broad utility in future research which takes into account the effect of parent–child bonding, especially with regard to “affectionless control” style parenting.

  3. HYPERBRANCHED CONJUGATIVE MACROMOLECULES CONSTRUCTED FROM TRIPLE-BOND BUILDING BLOCKS

    Institute of Scientific and Technical Information of China (English)

    Matthias H(a)uβler; Hong-chen Dong; Jacky Wing Yip Lam; Rong-hua Zheng; An-jun Qin; Ben-zhong Tang

    2005-01-01

    Polycyclotrimerization and polycoupling of acetylenic monomers respectively furnish hyperbranched polyarylenes and polyynes with high molecular weights (up to 1 × 106) in high yields (up to 99.9%). The polymers possess low intrinsic viscosities and high thermal stabilities, losing little of their weights when heated to > 400℃. Upon pyrolysis at > 800℃, the polymers graphitize with high char yields (up to 86%). Hyperbranched polyarylenes efficiently emit deep-blue to blue-green lights with fluorescence quantum yields up to 98% and strongly attenuate intense laser pulses with optical power-limiting performances superior to that of C60, a well-known optical limiter. Poly(alkenephenylenes), poly(aroylarylenes) and polyynes are readily cross-linkable by UV irradiation, serving as excellent photoresist materials for the generation of patterns with nanometer resolution. Thin films of hyperbranched polyynes exhibit very high refractive indexes (n up to 1.86). The internal and terminal acetylene moieties of the polyynes readily form complexes with cobalt carbonyls, which can be transformed into soft ferromagnetic ceramics with high magnetic susceptibilities (Ms up to ca. 118 emu/g) and near-zero magnetic losses.

  4. On Split Lie Triple Systems

    Indian Academy of Sciences (India)

    Antonio J Calderón Martín

    2009-04-01

    We begin the study of arbitrary split Lie triple systems by focussing on those with a coherent 0-root space. We show that any such triple systems with a symmetric root system is of the form $T=\\mathcal{U}+\\sum_j I_j$ with $\\mathcal{U}$ a subspace of the 0-root space $T_0$ and any $I_j$ a well described ideal of , satisfying $[I_j,T,I_k]=0$ if $j≠ k$. Under certain conditions, it is shown that is the direct sum of the family of its minimal ideals, each one being a simple split Lie triple system, and the simplicity of is characterized. The key tool in this job is the notion of connection of roots in the framework of split Lie triple systems.

  5. Zero Triple Product Determined Matrix Algebras

    Directory of Open Access Journals (Sweden)

    Hongmei Yao

    2012-01-01

    triple product in the aforementioned definition is replaced by Jordan triple product, then A is called zero Jordan triple product determined. This paper mainly shows that matrix algebra Mn(B, n≥3, where B is any commutative unital algebra even different from the above mentioned commutative unital algebra C, is always zero triple product determined, and Mn(F, n≥3, where F is any field with chF≠2, is also zero Jordan triple product determined.

  6. Bond Boom

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The Ministry of Finance recently kick-started a pilot program allowing local governments of Shanghai and Shenzhen,and Zhejiang and Guangdong provinces to issue bonds for the first time.How will the new policy affect fiscal capacities of local governments and the broader economy? What else should the country do to build a healthy bond market? Economists and experts discussed these issues in an interview with the Shanghai Securities Journal.Edited excerpts follow.

  7. Bond Boom

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The Ministry of Finance recently kick-started a pilot program allowing local governments of Shanghai and Shenzhen, and Zhejiang and Guangdong provinces to issue bonds for the first time. How will the new policy affect fiscal capacities of local governments and the broader economy? What else should the country do to build a healthy bond market? Economists and experts discussed these issues in an interview with the ShanghaiSecuritiesJournal. Edited excerpts follow:

  8. Photo-active collagen systems with controlled triple helix architecture

    CERN Document Server

    Tronci, Giuseppe; Wood, David J

    2013-01-01

    The design of photo-active collagen systems is presented as a basis for establishing biomimetic materials with varied network architecture and programmable macroscopic properties. Following in-house isolation of type I collagen, reaction with vinyl-bearing compounds of varied backbone rigidity, i.e. 4-vinylbenzyl chloride (4VBC) and glycidyl methacrylate (GMA), was carried out. TNBS colorimetric assay, 1H-NMR and ATR-FTIR confirmed covalent and tunable functionalization of collagen lysines. Depending on the type and extent of functionalization, controlled stability and thermal denaturation of triple helices were observed via circular dichroism (CD), whereby the hydrogen-bonding capability of introduced moieties was shown to play a major role. Full gel formation was observed following photo-activation of functionalized collagen solutions. The presence of a covalent network only slightly affected collagen triple helix conformation (as observed by WAXS and ATR-FTIR), confirming the structural organization of fun...

  9. Triple gastric peptic ulcer perforation.

    Science.gov (United States)

    Radojkovic, Milan; Mihajlovic, Suncica; Stojanovic, Miroslav; Stanojevic, Goran; Damnjanovic, Zoran

    2016-03-01

    Patients with advanced or metastatic cancer have compromised nutritional, metabolic, and immune conditions. Nevertheless, little is known about gastroduodenal perforation in cancer patients. Described in the present report is the case of a 41-year old woman with stage IV recurrent laryngeal cancer, who used homeopathic anticancer therapy and who had triple peptic ulcer perforation (PUP) that required surgical repair. Triple gastric PUP is a rare complication. Self-administration of homeopathic anticancer medication should be strongly discouraged when evidence-based data regarding efficacy and toxicity is lacking.

  10. Triple-helical peptides: an approach to collagen conformation, stability, and self-association.

    Science.gov (United States)

    Brodsky, Barbara; Thiagarajan, Geetha; Madhan, Balaraman; Kar, Karunakar

    2008-05-01

    Peptides have been an integral part of the collagen triple-helix structure story, and have continued to serve as useful models for biophysical studies and for establishing biologically important sequence-structure-function relationships. High resolution structures of triple-helical peptides have confirmed the basic Ramachandran triple-helix model and provided new insights into the hydration, hydrogen bonding, and sequence dependent helical parameters in collagen. The dependence of collagen triple-helix stability on the residues in its (Gly-X-Y)(n) repeating sequence has been investigated by measuring melting temperatures of host-guest peptides and an on-line collagen stability calculator is now available. Although the presence of Gly as every third residue is essential for an undistorted structure, interruptions in the repeating (Gly-X-Y)(n) amino acid sequence pattern are found in the triple-helical domains of all nonfibrillar collagens, and are likely to play a role in collagen binding and degradation. Peptide models indicate that small interruptions can be incorporated into a rod-like triple-helix with a highly localized effect, which perturbs hydrogen bonds and places the standard triple-helices on both ends out of register. In contrast to natural interruptions, missense mutations which replace one Gly in a triple-helix domain by a larger residue have pathological consequences, and studies on peptides containing such Gly substitutions clarify their effect on conformation, stability, and folding. Recent studies suggest peptides may also be useful in defining the basic principles of collagen self-association to the supramolecular structures found in tissues.

  11. Solution Patterns Predicting Pythagorean Triples

    Science.gov (United States)

    Ezenweani, Ugwunna Louis

    2013-01-01

    Pythagoras Theorem is an old mathematical treatise that has traversed the school curricula from secondary to tertiary levels. The patterns it produced are quite interesting that many researchers have tried to generate a kind of predictive approach to identifying triples. Two attempts, namely Diophantine equation and Brahmagupta trapezium presented…

  12. Classifying Two-dimensional Hyporeductive Triple Algebras

    CERN Document Server

    Issa, A Nourou

    2010-01-01

    Two-dimensional real hyporeductive triple algebras (h.t.a.) are investigated. A classification of such algebras is presented. As a consequence, a classification of two-dimensional real Lie triple algebras (i.e. generalized Lie triple systems) and two-dimensional real Bol algebras is given.

  13. Photo-active collagen systems with controlled triple helix architecture.

    Science.gov (United States)

    Tronci, Giuseppe; Russell, Stephen J; Wood, David J

    2013-08-14

    The design of photo-active collagen systems is presented as a basis for establishing biomimetic materials with varied network architecture and programmable macroscopic properties. Following in-house isolation of type I collagen, reaction with vinyl-bearing compounds of varied backbone rigidity, i.e. 4-vinylbenzyl chloride (4VBC) and glycidyl methacrylate (GMA), was carried out. TNBS colorimetric assay, (1)H-NMR and ATR-FTIR confirmed covalent and tunable functionalization of collagen lysines. Depending on the type and extent of functionalization, controlled stability and thermal denaturation of triple helices were observed via circular dichroism (CD), whereby the hydrogen-bonding capability of introduced moieties was shown to play a major role. Full gel formation was observed following photo-activation of functionalized collagen solutions. The presence of a covalent network only slightly affected collagen triple helix conformation (as observed by WAXS and ATR-FTIR), confirming the structural organization of functionalized collagen precursors. Photo-activated hydrogels demonstrated an increased denaturation temperature (DSC) with respect to native collagen, suggesting that the formation of the covalent network successfully stabilized collagen triple helices. Moreover, biocompatibility and mechanical competence of obtained hydrogels were successfully demonstrated under physiologically-relevant conditions. These results demonstrate that this novel synthetic approach enabled the formation of biocompatible collagen systems with defined network architecture and programmable macroscopic properties, which can only partially be obtained with current synthetic methods.

  14. Unraveling high precision stereocontrol in a triple cascade organocatalytic reaction.

    Science.gov (United States)

    Shinisha, C B; Sunoj, Raghavan B

    2008-11-07

    The mechanism and stereoselectivity in an organocatalyzed triple cascade reaction between an aldehyde, electron deficient olefin and an alpha,beta-unsaturated aldehyde are investigated for the first time using density functional theory. The factors responsible for high levels of observed stereoselectivity (Enders et al., Nature, 2006, 441, 861) towards the generation of cyclohexene carbaldehyde with four contiguous stereocentres are unravelled. The triple cascade reaction, comprising a Michael, Michael and aldol sequence as the key elementary reactions, is studied by identifying the corresponding transition states for the stereoselective C-C bond-formation. In the first Michael addition step between the enamine (derived from the chiral catalyst and propanal) and nitrostyrene, energetically the most preferred mode of addition is found to be between the si-face of (E)-anti-enamine on the si-face of nitrostyrene. The addition of the si-face of the nitroalkane anion on the re-face of the iminium ion (formed between the enal and the catalyst) is the lowest energy pathway for the second Michael addition step. The high level of asymmetric induction is rationalized with the help of relative activation barriers associated with the competitive diastereomeric pathways. Interesting weak interactions, along with the steric effects offered by the bulky alpha-substituent on the pyrrolidine ring, are identified as critical to the stereoselectivity in this triple cascade reaction. The predicted stereoselectivities using computed energetics are found to be in perfect harmony with the experimental stereoselectivities.

  15. TripleR: an R package for social relations analyses based on round-robin designs.

    Science.gov (United States)

    Schönbrodt, Felix D; Back, Mitja D; Schmukle, Stefan C

    2012-06-01

    In this article, we present TripleR, an R package for the calculation of social relations analyses (Kenny, 1994) based on round-robin designs. The scope of existing software solutions is ported to R and enhanced with previously unimplemented methods of significance testing in single groups (Lashley & Bond, 1997) and handling of missing values. The package requires only minimal knowledge of R, and results can be exported for subsequent analyses to other software packages. We demonstrate the use of TripleR with several didactic examples.

  16. The nature of solid-state N-H triplebondO/O-H triplebond N tautomeric competition in resonant systems. Intramolecular proton transfer in low-barrier hydrogen bonds formed by the triplebond O=C-C=N-NH triple bond --> <-- triplebond HO-C=C-N=N triplebond Ketohydrazone-Azoenol system. A variable-temperature X-ray crystallographic and DFT computational study.

    Science.gov (United States)

    Gilli, Paola; Bertolasi, Valerio; Pretto, Loretta; Lycka, Antonín; Gilli, Gastone

    2002-11-13

    The tautomeric.O=C-C=N-NH triplebond --> competition in these compounds is studied here through variable-temperature (100, 150, 200, and 295 K) crystal-structure determination of pF = 1-(4-F-phenylazo)2-naphthol and oF = 1-(2-F-phenylazo)2-naphthol, two molecules that, on the ground of previous studies (Gilli, P; Bertolasi, V.; Ferretti, V.; Gilli, G. J. Am. Chem. Soc. 2000, 122, 10405), were expected to represent an almost perfect balance of the two tautomers. According to predictions, the two molecules form remarkably strong bonds (d(N triplebond O) = 2.53-2.55 A) of double-minimum or LBHB type with dynamic N-H triplebond O/ O-H triplebond N exchange in the solid state. The enthalpy differences between the two minima, as measured by van't Hoff methods from the X-ray-determined proton populations, are very small and amount to DeltaH degrees = -0.120 and DeltaH degrees = -0.156 kcal mol(-)(1) in favor of the N-H triplebond O form for pF and oF, respectively. Successive emulation of pF by DFT methods at the B3LYP/6-31+G(d,p)//B3LYP/6-31+G(d,p) level has shown that both energetic and geometric experimental aspects can be almost perfectly reproduced. Generalization of these results was sought by performing DFT calculations at the same level of theory along the complete proton-transfer (PT) pathway for five test molecules designed in such a way that the RAHB formed changes smoothly from weak N-H triplebond O to strong O-H.N through very strong N-H triplebond O/O-H triplebond N bond of LBHB type. A systematic correlation analysis of H-bond energies, H-bond and pi-conjugated fragment geometries, and H-bond Bader's AIM topological properties performed along the PT-pathways leads to the following conclusions: (a) any X-H triplebond Y H-bonded system is fully characterized by its intrinsic PT-barrier, that is, the symmetric barrier occurring when the proton affinities of X and Y are identical; (b) the intrinsic X-H triplebond Y bond associated with the symmetric barrier is

  17. The evolution of triple-star systems

    Science.gov (United States)

    Toonen, Silvia; Hamers, Adrian; Portegies Zwart, Simon

    2017-01-01

    While the principles of stellar and binary evolution theory have been accepted for a long time, our understanding of triple-star evolution is lagging behind. It is important to understand these systems, as triples are common in the field. About 15% of low-mass stellar systems are triples, but for high-mass stars the fraction increases to over 50%. At the same time, triple evolution is often invoked to explain exotic systems which cannot be explained easily by binary evolution. Examples are low-mass X-ray binaries, supernova type Ia progenitors and blue stragglers.Modeling triple evolution, however, is challenging as it is a combination of three-body dynamics and stellar evolution. In the past, most studies of three-body systems have focused on purely dynamical aspects without taking stellar evolution into account. However, in recent years, the first interdisciplinary studies have taken place which demonstrate the richness of the interacting regime. Here, I will show the first results of our new code TRES for simulating the evolution of stellar triples, which combines stellar evolution and interactions with three-body dynamics. In this talk, I will give an overview of the evolution of realistic (stellar) triples and I will discuss how triple evolution differs from binary evolution. What are the common evolutionary pathways that triple systems evolve through? Are there any evolutionary pathways open to triples, which are not open to isolated binaries? These are some of the important questions we want to answer.

  18. Energy Efficient Triple IG Automation EEE (Triple-E)

    Energy Technology Data Exchange (ETDEWEB)

    McGlinchy, Timothy B

    2013-02-28

    GED Integrated Solutions collaborated with US window and door manufactures to investigate, design and verify technical and cost feasibility for producing high performance, high volume, low material and labor cost window, utilizing a modified window design containing a triple insulating glass unit (IGU). This window design approach when combined with a high volume IGU manufacturing system, can produce R5 rated windows for an approximate additional consumer cost of only $4 per square foot when compared to conventional Low-E argon dual pane IG windows, resulting in a verify practical, reliable and affordable high performance window for public use.

  19. Generalized derivations of Lie triple systems

    Directory of Open Access Journals (Sweden)

    Zhou Jia

    2016-01-01

    Full Text Available In this paper, we present some basic properties concerning the derivation algebra Der (T, the quasiderivation algebra QDer (T and the generalized derivation algebra GDer (T of a Lie triple system T, with the relationship Der (T ⊆ QDer (T ⊆ GDer (T ⊆ End (T. Furthermore, we completely determine those Lie triple systems T with condition QDer (T = End (T. We also show that the quasiderivations of T can be embedded as derivations in a larger Lie triple system.

  20. NMR shows hydrophobic interactions replace glycine packing in the triple helix at a natural break in the (Gly-X-Y)n repeat.

    Science.gov (United States)

    Li, Yingjie; Brodsky, Barbara; Baum, Jean

    2007-08-03

    Little is known about the structural consequences of the more than 20 breaks in the (Gly-X-Y)(n) repeating sequence found in the long triple helix domain of basement membrane type IV collagen. NMR triple resonance studies of doubly labeled residues within a set of collagen model peptides provide distance and dihedral angle restraints that allow determination of model structures of both a standard triple helix and of a triple helix with a break in solution. Although the standard triple helix cannot continue when Gly is not every third residue, the NMR data support rod-like molecules that have standard triple-helical structures on both sides of a well defined and highly localized perturbation. The GAAVM break region may be described as a "pseudo triple helix," because it preserves the standard one-residue stagger of the triple helix but introduces hydrophobic interactions at the position normally occupied by the much smaller and hydrogen-bonded Gly residue of the repeating (Gly-X-Y)(n) sequence. This structure provides a rationale for the consensus presence of hydrophobic residues in breaks of similar length and defines a novel variant of a triple helix that could be involved in recognition.

  1. Holonomy loops, spectral triples and quantum gravity

    DEFF Research Database (Denmark)

    Johannes, Aastrup; Grimstrup, Jesper Møller; Nest, Ryszard

    2009-01-01

    We review the motivation, construction and physical interpretation of a semi-finite spectral triple obtained through a rearrangement of central elements of loop quantum gravity. The triple is based on a countable set of oriented graphs and the algebra consists of generalized holonomy loops...

  2. Existence Regions of Shock Wave Triple Configurations

    Science.gov (United States)

    Bulat, Pavel V.; Chernyshev, Mikhail V.

    2016-01-01

    The aim of the research is to create the classification for shock wave triple configurations and their existence regions of various types: type 1, type 2, type 3. Analytical solutions for limit Mach numbers and passing shock intensity that define existence region of every type of triple configuration have been acquired. The ratios that conjugate…

  3. Nonunital Spectral Triples Associated to Degenerate Metrics

    Science.gov (United States)

    Rennie, A.

    We show that one can define (p,∞)-summable spectral triples using degenerate metrics on smooth manifolds. Furthermore, these triples satisfy Connes-Moscovici's discrete and finite dimension spectrum hypothesis, allowing one to use the Local Index Theorem [1] to compute the pairing with K-theory. We demonstrate this with a concrete example.

  4. The Killing Forms of Lie Triple Systems

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhi Xue; GAO Rui

    2009-01-01

    For Lie triple systems in the characteristic zero setting, we obtain by means of the Killing forms two criterions for semisimplicity and for solvability respectively, and then investigate the relationship among the Killing forms of a real Lie triple system To, the complexification T of To, and the realification of T.

  5. Conformational effects of Gly-X-Gly interruptions in the collagen triple helix.

    Science.gov (United States)

    Bella, Jordi; Liu, Jingsong; Kramer, Rachel; Brodsky, Barbara; Berman, Helen M

    2006-09-15

    The collagen model peptide with sequence (Pro-Hyp-Gly)4-Pro-Gly-(Pro-Hyp-Gly)5 contains a central Gly-Pro-Gly interruption in the consensus collagen sequence. Its high-resolution crystal structure defines the molecular consequences of such an interruption for the collagen triple-helical conformation, and provides insight into possible structural and biological roles of similar interruptions in the -Gly-X-Y- repeating pattern found in non-fibrillar collagens. The peptide (denoted as the Hyp minus peptide or Hyp-) forms a rod-like triple helix structure without any bend or kink, and crystallizes in a quasi-hexagonal lattice. The two Pro-Hyp-Gly zones adopt the typical triple-helical collagen conformation with standard Rich and Crick II hydrogen bonding topology. Notably, the central zone containing the Gly-Pro-Gly interruption deviates from the standard structure in terms of hydrogen bonding topology, torsion angles, helical, and superhelical parameters. These deviations are highly localized, such that the standard features are regained within one to two residues on either side. Conformational variations and high temperature factors seen for the six chains of the asymmetric unit in the zone around the interruption point to the presence of a local region of considerable plasticity and flexibility embedded within two highly rigid and ordered standard triple-helical segments. The structure suggests a role for Gly-X-Gly interruptions as defining regions of flexibility and molecular recognition in the otherwise relatively uniform repeating collagen conformation.

  6. Switchable proline derivatives: tuning the conformational stability of the collagen triple helix by pH changes.

    Science.gov (United States)

    Siebler, Christiane; Erdmann, Roman S; Wennemers, Helma

    2014-09-22

    (4S)-Aminoproline is introduced as a pH-sensitive probe for tuning the conformational properties of peptides and proteins. The pH-triggered flip of the ring puckering and the formation/release of a transannular H bond were used to switch the formation of collagen triple helices on and off reversibly.

  7. Contractive spectral triples for crossed products

    CERN Document Server

    Paterson, Alan L T

    2012-01-01

    Connes showed that spectral triples encode (noncommutative) metric information. Further, Connes and Moscovici in their metric bundle construction showed that, as with the Takesaki duality theorem, forming a crossed product spectral triple can substantially simplify the structure. In a recent paper, Bellissard, Marcolli and Reihani (among other things) studied in depth metric notions for spectral triples and crossed product spectral triples for $Z$-actions, with applications in number theory and coding theory. In the work of Connes and Moscovici, crossed products involving groups of diffeomorphisms and even of \\'{e}tale groupoids are required. With this motivation, the present paper develops part of the Bellissard-Marcolli-Reihani theory for a general discrete group action, and in particular, introduces coaction spectral triples and their associated metric notions. The isometric condition is replaced by the contractive condition.

  8. Transient collagen triple helix binding to a key metalloproteinase in invasion and development.

    Science.gov (United States)

    Zhao, Yingchu; Marcink, Thomas C; Sanganna Gari, Raghavendar Reddy; Marsh, Brendan P; King, Gavin M; Stawikowska, Roma; Fields, Gregg B; Van Doren, Steven R

    2015-02-03

    Skeletal development and invasion by tumor cells depends on proteolysis of collagen by the pericellular metalloproteinase MT1-MMP. Its hemopexin-like (HPX) domain binds to collagen substrates to facilitate their digestion. Spin labeling and paramagnetic nuclear magnetic resonance (NMR) detection have revealed how the HPX domain docks to collagen I-derived triple helix. Mutations impairing triple-helical peptidase activity corroborate the interface. Saturation transfer difference NMR suggests rotational averaging around the longitudinal axis of the triple-helical peptide. Part of the interface emerges as unique and potentially targetable for selective inhibition. The triple helix crosses the junction of blades I and II at a 45° angle to the symmetry axis of the HPX domain, placing the scissile Gly∼Ile bond near the HPX domain and shifted ∼25 Å from MMP-1 complexes. This raises the question of the MT1-MMP catalytic domain folding over the triple helix during catalysis, a possibility accommodated by the flexibility between domains suggested by atomic force microscopy images.

  9. The triple system Zeta Aquarii

    CERN Document Server

    Tokovinin, Andrei

    2016-01-01

    Zeta Aquarii is a bright and nearby (28 pc) triple star with a 26-year astrometric subsystem. Almost a half of the outer 540-year visual orbit has been covered in 238 years of its observations. Both inner and outer orbits are revised here taking into account recent direct resolution of the inner pair Aa,Ab. The inner orbit has a high eccentricity of 0.87 and is inclined to the outer orbit by 140+-10 degrees, suggesting that Kozai-Lidov cycles take place. The masses of the stars Aa, B, and Ab are 1.4, 1.4, and 0.6 solar. The age of the system is about 3 Gyr, and the two main components have just left the main sequence. Hypothetically, this system could have formed by a dynamical capture of the small star Ab in the twin binary Aa,B.

  10. Collisions in young triple systems

    CERN Document Server

    Rawiraswattana, Krisada; Goodwin, Simon P

    2011-01-01

    We perform N-body simulations of young triple systems consisting of two low-mass companions orbiting around a significantly more massive primary. We find that, when the orbits of the companions are coplanar and not too widely separated, the chance of a collision between the two companions can be as high as 20 per cent. Collisions between one of the companions (always the less massive) and the primary can also occur in systems with unequal-mass companions. The chance of collisions is a few per cent in systems with more realistic initial conditions, such as with slightly non-coplanar orbits and unequal-mass companions. If the companions start widely separated then collision are very rare except in some cases when the total mass of the companions is large. We suggest that collisions between members of young multiple systems may explain some unusual young multiple systems such as apparently non-coeval companions.

  11. Covalent bonding from alchemical linear response density functional theory

    CERN Document Server

    Chang, K Y Samuel; Ramakrishnan, Raghunathan; von Lilienfeld, O Anatole

    2015-01-01

    We assess the predictive accuracy of linear response based estimates of changes in covalent bonding due to linear alchemical interpolations among molecules. We have investigated single bonds to hydrogen, as well as single, double, and triple bonds between main-group elements, occurring in small iso-electronic molecular spaces with atomic elements drawn from rows 2-3 in the $p$-block of the periodic table. Numerical evidence suggests that first order estimates of bonding potentials can achieve chemical accuracy if the alchemical interpolation connects molecules containing late elements in the periodic table (3$^{rd}$ and 4$^{th}$ row) and identical number of atoms and molecular geometries. For these interpolations, changes in bonding potential are near-linear in the coupling parameter, resulting in accurate Hellmann-Feynman predictions. Second order estimates for such interpolations yield worse predictions. The predictions become substantially worse if initial and final molecules differ not only in composition...

  12. Cross Shear Roll Bonding

    DEFF Research Database (Denmark)

    Bay, Niels; Bjerregaard, Henrik; Petersen, Søren. B;

    1994-01-01

    The present paper describes an investigation of roll bonding an AlZn alloy to mild steel. Application of cross shear roll bonding, where the two equal sized rolls run with different peripheral speed, is shown to give better bond strength than conventional roll bonding. Improvements of up to 20......-23% in bond strength are found and full bond strength is obtained at a reduction of 50% whereas 65% is required in case of conventional roll bonding. Pseudo cross shear roll bonding, where the cross shear effect is obtained by running two equal sized rolls with different speed, gives the same results....

  13. Reverse triple I method of fuzzy reasoning

    Institute of Scientific and Technical Information of China (English)

    宋士吉; 吴澄

    2002-01-01

    A theory of reverse triple I method with sustention degree is presented by using the implication operator R0 in every step of the fuzzy reasoning. Its computation formulas of supremum for fuzzy modus ponens and infimum for fuzzy modus tollens are given respectively. Moreover, through the generalization of this problem, the corresponding formulas of ?-reverse triple I method with sustention degree are also obtained. In addition, the theory of reverse triple I method with restriction degree is proposed as well by using the operator R0, and the computation formulas of infimum for fuzzy modus ponens and supremum for fuzzy modus tollens are shown.

  14. Wire bonding in microelectronics

    CERN Document Server

    Harman, George G

    2010-01-01

    Wire Bonding in Microelectronics, Third Edition, has been thoroughly revised to help you meet the challenges of today's small-scale and fine-pitch microelectronics. This authoritative guide covers every aspect of designing, manufacturing, and evaluating wire bonds engineered with cutting-edge techniques. In addition to gaining a full grasp of bonding technology, you'll learn how to create reliable bonds at exceedingly high yields, test wire bonds, solve common bonding problems, implement molecular cleaning methods, and much more. Coverage includes: Ultrasonic bonding systems and technologies, including high-frequency systems Bonding wire metallurgy and characteristics, including copper wire Wire bond testing Gold-aluminum intermetallic compounds and other interface reactions Gold and nickel-based bond pad plating materials and problems Cleaning to improve bondability and reliability Mechanical problems in wire bonding High-yield, fine-pitch, specialized-looping, soft-substrate, and extreme-temperature wire bo...

  15. The triple helix perspective of innovation systems

    NARCIS (Netherlands)

    Leydesdorff, L.; Zawdie, G.

    2010-01-01

    Alongside the neo-institutional model of networked relations among universities, industries, and governments, the triple helix can be provided with a neo-evolutionary interpretation as three selection environments operating upon one another: markets, organisations and technological opportunities. Ho

  16. On triple factorisations of finite groups

    CERN Document Server

    Alavi, S Hassan

    2009-01-01

    This paper introduces and develops a general framework for studying triple factorisations of the form $G=ABA$ of finite groups $G$, with $A$ and $B$ subgroups of $G$. We call such a factorisation nondegenerate if $G\

  17. Integration of robust fluidic interconnects using metal to glass anodic bonding

    Science.gov (United States)

    Briand, Danick; Weber, Patrick; de Rooij, Nicolaas F.

    2005-09-01

    This paper reports on the encapsulation of a piezoresistive silicon/Pyrex liquid flow sensor using metal to glass anodic bonding. The bonding technique allowed integrating robust metallic microfluidic interconnects and eliminating the use of glue and O-rings. The bonding parameters of a silicon/Pyrex/metal triple stack were chosen to minimize the residual stress and to obtain a strong and liquid tight bonding interface. The silicon/Pyrex liquid flow sensor was successfully bonded to metallic plates of Kovar and Alloy 42, on which tubes were fixed and a printed circuit board (PCB) was integrated. A post-bonding annealing procedure was developed to reduce the residual bonding stress. The characteristics of the encapsulated liquid flow sensor, such as the temperature coefficient of sensitivity, fulfilled the specifications. Wafer level packaging using metal to glass anodic bonding was considered to reduce the packaging size and cost.

  18. Triple Pulsar Tests Mass Triplets

    CERN Document Server

    Shao, Lijing

    2016-01-01

    Three conceptually different masses appear in equations of motion for objects under gravity, namely, inertial mass, $m_{\\cal I}$, passive gravitational mass, $m_{\\cal P}$, and active gravitational mass, $m_{\\cal A}$. It is assumed that, for any objects, $m_{\\cal I} = m_{\\cal P} = m_{\\cal A}$ in Newtonian gravity, and $m_{\\cal I} = m_{\\cal P}$ in Einsteinian gravity, oblivious to objects' sophisticated internal structure. Empirical examination of the equivalence probes deep into gravity theories. We propose new tests based on pulsar timing of the stellar triple system, PSR J0337+1715. Various machine-precision three-body simulations are performed, from which, equivalence-violating parameters are extracted with Markov chain Monte Carlo sampling that takes full correlations into account. We show that the difference in masses can be probed to $3\\times10^{-8}$, improving the post-Newtonian constraints of strong equivalence principle by $10^3$--$10^6$. The test of $m_{\\cal P}=m_{\\cal A}$ presents the first test of ...

  19. The collagen triple-helix structure.

    Science.gov (United States)

    Brodsky, B; Ramshaw, J A

    1997-03-01

    Recent advances, principally through the study of peptide models, have led to an enhanced understanding of the structure and function of the collagen triple helix. In particular, the first crystal structure has clearly shown the highly ordered hydration network critical for stabilizing both the molecular conformation and the interactions between triple helices. The sequence dependent nature of the conformational features is also under active investigation by NMR and other techniques. The triple-helix motif has now been identified in proteins other than collagens, and it has been established as being important in many specific biological interactions as well as being a structural element. The nature of recognition and the degree of specificity for interactions involving triple helices may differ from globular proteins. Triple-helix binding domains consist of linear sequences along the helix, making them amenable to characterization by simple model peptides. The application of structural techniques to such model peptides can serve to clarify the interactions involved in triple-helix recognition and binding and can help explain the varying impact of different structural alterations found in mutant collagens in diseased states.

  20. An important base triple anchors the substrate helix recognition surface within the Tetrahymena ribozyme active site.

    Science.gov (United States)

    Szewczak, A A; Ortoleva-Donnelly, L; Zivarts, M V; Oyelere, A K; Kazantsev, A V; Strobel, S A

    1999-09-28

    Key to understanding the structural biology of catalytic RNA is determining the underlying networks of interactions that stabilize RNA folding, substrate binding, and catalysis. Here we demonstrate the existence and functional importance of a Hoogsteen base triple (U300.A97-U277), which anchors the substrate helix recognition surface within the Tetrahymena group I ribozyme active site. Nucleotide analog interference suppression analysis of the interacting functional groups shows that the U300.A97-U277 triple forms part of a network of hydrogen bonds that connect the P3 helix, the J8/7 strand, and the P1 substrate helix. Product binding and substrate cleavage kinetics experiments performed on mutant ribozymes that lack this base triple (C A-U, U G-C) or replace it with the isomorphous C(+).G-C triple show that the A97 Hoogsteen triple contributes to the stabilization of both substrate helix docking and the conformation of the ribozyme's active site. The U300. A97-U277 base triple is not formed in the recently reported crystallographic model of a portion of the group I intron, despite the presence of J8/7 and P3 in the RNA construct [Golden, B. L., Gooding, A. R., Podell, E. R. & Cech, T. R. (1998) Science 282, 259-264]. This, along with other biochemical evidence, suggests that the active site in the crystallized form of the ribozyme is not fully preorganized and that substantial rearrangement may be required for substrate helix docking and catalysis.

  1. Self-association of collagen triple helic peptides into higher order structures.

    Science.gov (United States)

    Kar, Karunakar; Amin, Priyal; Bryan, Michael A; Persikov, Anton V; Mohs, Angela; Wang, Yuh-Hwa; Brodsky, Barbara

    2006-11-03

    Interest in self-association of peptides and proteins is motivated by an interest in the mechanism of physiologically higher order assembly of proteins such as collagen as well as the mechanism of pathological aggregation such as beta-amyloid formation. The triple helical form of (Pro-Hyp-Gly)(10), a peptide that has proved a useful model for molecular features of collagen, was found to self-associate, and its association properties are reported here. Turbidity experiments indicate that the triple helical peptide self-assembles at neutral pH via a nucleation-growth mechanism, with a critical concentration near 1 mM. The associated form is more stable than individual molecules by about 25 degrees C, and the association is reversible. The rate of self-association increases with temperature, supporting an entropically favored process. After self-association, (Pro-Hyp-Gly)(10) forms branched filamentous structures, in contrast with the highly ordered axially periodic structure of collagen fibrils. Yet a number of characteristics of triple helix assembly for the peptide resemble those of collagen fibril formation. These include promotion of fibril formation by neutral pH and increasing temperature; inhibition by sugars; and a requirement for hydroxyproline. It is suggested that these similar features for peptide and collagen self-association are based on common lateral underlying interactions between triple helical molecules mediated by hydrogen-bonded hydration networks involving hydroxyproline.

  2. Nonlinear optical response of the collagen triple helix and second harmonic microscopy of collagen liquid crystals

    Science.gov (United States)

    Deniset-Besseau, A.; De Sa Peixoto, P.; Duboisset, J.; Loison, C.; Hache, F.; Benichou, E.; Brevet, P.-F.; Mosser, G.; Schanne-Klein, M.-C.

    2010-02-01

    Collagen is characterized by triple helical domains and plays a central role in the formation of fibrillar and microfibrillar networks, basement membranes, as well as other structures of the connective tissue. Remarkably, fibrillar collagen exhibits efficient Second Harmonic Generation (SHG) and SHG microscopy proved to be a sensitive tool to score fibrotic pathologies. However, the nonlinear optical response of fibrillar collagen is not fully characterized yet and quantitative data are required to further process SHG images. We therefore performed Hyper-Rayleigh Scattering (HRS) experiments and measured a second order hyperpolarisability of 1.25 10-27 esu for rat-tail type I collagen. This value is surprisingly large considering that collagen presents no strong harmonophore in its amino-acid sequence. In order to get insight into the physical origin of this nonlinear process, we performed HRS measurements after denaturation of the collagen triple helix and for a collagen-like short model peptide [(Pro-Pro-Gly)10]3. It showed that the collagen large nonlinear response originates in the tight alignment of a large number of weakly efficient harmonophores, presumably the peptide bonds, resulting in a coherent amplification of the nonlinear signal along the triple helix. To illustrate this mechanism, we successfully recorded SHG images in collagen liquid solutions by achieving liquid crystalline ordering of the collagen triple helices.

  3. Building a Distributed Infrastructure for Scalable Triple Stores

    Institute of Scientific and Technical Information of China (English)

    Jing Zhou; Wendy Hall; David De Roure

    2009-01-01

    Built specifically for the Semantic Web, triple stores are required to accommodate a large number of RDF triples and remain primarily centralized. As triple stores grow and evolve with time, there is a demanding need for scalable techniques to remove resource and performance bottlenecks in such systems. To this end, we propose a fully decentralized peer-to-peer architecture for large scale triple stores in which triples are maintained by individual stakeholders, and a semantics-directed search protocol, mediated by topology reorganization, for locating triples of interest. We test our design through simulations and the results show anticipated improvements over existing techniques for distributed triple stores. In addition to engineering future large scale triple stores, our work will in particular benefit the federation of stand-alone triple stores of today to achieve desired scalability.

  4. On Split Lie Triple Systems II

    Indian Academy of Sciences (India)

    Antonio J Calderón Martín; M Forero Piulestán

    2010-04-01

    In [4] it is studied that the structure of split Lie triple systems with a coherent 0-root space, that is, satisfying $[T_0,T_0,T]=0$ and $[T_0,T_,T_0]≠ 0$ for any nonzero root and where $T_0$ denotes the 0-root space and $T_$ the -root space, by showing that any of such triple systems with a symmetric root system is of the form $T=\\mathcal{U}+\\sum_j I_j$ with $\\mathcal{U}$ a subspace of the 0-root space $T_0$ and any $I_j$ a well described ideal of , satisfying $[I_j,T,I_k]=0$ if $j≠ k$. It is also shown in [4] that under certain conditions, a split Lie triple system with a coherent 0-root space is the direct sum of the family of its minimal ideals, each one being a simple split Lie triple system, and the simplicity of is characterized. In the present paper we extend these results to arbitrary split Lie triple systems with no restrictions on their 0-root spaces.

  5. Bonding with Your Baby

    Science.gov (United States)

    ... in infant massage in your area. Breastfeeding and bottle-feeding are both natural times for bonding. Infants respond ... activities include: participating together in labor and delivery feeding ( breast or bottle ); sometimes dad forms a special bond with baby ...

  6. Triple helix interactions for eco-innovation

    DEFF Research Database (Denmark)

    Hermann, Roberto Rivas; Riisgaard, Henrik; Remmen, Arne

    Authority with insights from consultants, universities and donnor agencies. The proximity of the science park to the canal, has hitherto not yielded with the creation of a “green cluster”, which could be a precedent to promote eco-innovations. These findings suggest that, Triple Helix interactions...... the role of science parks in promoting eco-innovation. This study uses qualitative data gathered in two units of analysis: Panama Canal Authority and City of Knowledge Science Park. The study examines how Triple Helix interactions have built the regional system of eco-innovation at the Panama Canal...... are not institutionalized but take place through adhoc projects. Further, science parks could become mediators in Triple Helix interactions between industry, universities and governments....

  7. Double Fell bundles and Spectral triples

    CERN Document Server

    Martins, Rachel A D

    2007-01-01

    As a natural and canonical extension of Kumjian's Fell bundles over groupoids \\cite{fbg}, we give a definition for a double Fell bundle (a double category) over a double groupoid. We show that finite dimensional double category Fell line bundles tensored with their dual with $S^o$-reality satisfy the finite real spectral triples axioms but not necessarily orientability. This means that these product bundles with noncommutative algebras can be regarded as noncommutative compact manifolds more general than real spectral triples as they are not necessarily orientable. By construction, they unify the noncommutative geometry axioms and hence provide an algebraic enveloping structure for finite spectral triples to give the Dirac operator $D$ new algebraic and geometric structures that are otherwise missing in the transition from Fredholm operator to Dirac operator. The Dirac operator in physical applications as a result becomes less ad hoc. The new noncommutative space we present is a complex line bundle over a dou...

  8. A novel DNA computing model based on RecA-mediated triple-stranded DNA structure

    Institute of Scientific and Technical Information of China (English)

    Fang Gang; Zhang Shemin; Dong Yafei; Xu Jin

    2007-01-01

    The field of DNA computing emerged in 1994 after Adleman's paper was published. Henceforth, a few scholars solved some noted NP-complete problems in this way. And all these methods of DNA computing are based on conventional Watson-Crick hydrogen bond of doublehelical DNA molecule. In this paper, we show that the triple-stranded DNA structure mediated by RecA protein can be used for solving computational problems. Sequence-specific recognition of double-stranded DNA by oligonucleotide-directed triple helix (triplex) formation is used to carry out the algorithm. We present procedure for the 3-vertex-colorability problems. In our proposed procedure, it is suggested that it is possible to solve more complicated problems with more variables by this model.

  9. Normalization for triple-target microarray experiments

    Directory of Open Access Journals (Sweden)

    Magniette Frederic

    2008-04-01

    Full Text Available Abstract Background Most microarray studies are made using labelling with one or two dyes which allows the hybridization of one or two samples on the same slide. In such experiments, the most frequently used dyes are Cy3 and Cy5. Recent improvements in the technology (dye-labelling, scanner and, image analysis allow hybridization up to four samples simultaneously. The two additional dyes are Alexa488 and Alexa494. The triple-target or four-target technology is very promising, since it allows more flexibility in the design of experiments, an increase in the statistical power when comparing gene expressions induced by different conditions and a scaled down number of slides. However, there have been few methods proposed for statistical analysis of such data. Moreover the lowess correction of the global dye effect is available for only two-color experiments, and even if its application can be derived, it does not allow simultaneous correction of the raw data. Results We propose a two-step normalization procedure for triple-target experiments. First the dye bleeding is evaluated and corrected if necessary. Then the signal in each channel is normalized using a generalized lowess procedure to correct a global dye bias. The normalization procedure is validated using triple-self experiments and by comparing the results of triple-target and two-color experiments. Although the focus is on triple-target microarrays, the proposed method can be used to normalize p differently labelled targets co-hybridized on a same array, for any value of p greater than 2. Conclusion The proposed normalization procedure is effective: the technical biases are reduced, the number of false positives is under control in the analysis of differentially expressed genes, and the triple-target experiments are more powerful than the corresponding two-color experiments. There is room for improving the microarray experiments by simultaneously hybridizing more than two samples.

  10. The triple point of sulfur hexafluoride

    Science.gov (United States)

    Rourke, P. M. C.

    2016-04-01

    A cryogenic fixed point cell has been filled with high purity (99.999%) sulfur hexafluoride (SF6) and measured in an adiabatic closed-cycle cryostat system. Temperature measurements of the SF6 melting curve were performed using a capsule-type standard platinum resistance thermometer (CSPRT) calibrated over the International Temperature Scale of 1990 (ITS-90) subrange from the triple point of equilibrium hydrogen to the triple point of water. The measured temperatures were corrected by 0.37 mK for the effects of thermometer self-heating, and the liquidus-point temperature estimated by extrapolation to melted fraction F  =  1 of a simple linear regression versus melted fraction F in the range F  =  0.53 to 0.84. Based on this measurement, the temperature of the triple point of sulfur hexafluoride is shown to be 223.555 23(49) K (k  =  1) on the ITS-90. This value is in excellent agreement with the best prior measurements reported in the literature, but with considerably smaller uncertainty. An analysis of the detailed uncertainty budget of this measurement suggests that if the triple point of sulfur hexafluoride were to be included as a defining fixed point of the next revision of the International Temperature Scale, it could do so with a total realization uncertainty of approximately 0.43 mK, slightly larger than the realization uncertainties of the defining fixed points of the ITS-90. Since the combined standard uncertainty of this SF6 triple point temperature determination is dominated by chemical impurity effects, further research exploring gas purification techniques and the influence of specific impurity species on the SF6 triple point temperature may bring the realization uncertainty of SF6 as a fixed point material into the range of the defining fixed points of the ITS-90.

  11. Acrylic mechanical bond tests

    Energy Technology Data Exchange (ETDEWEB)

    Wouters, J.M.; Doe, P.J.

    1991-02-01

    The tensile strength of bonded acrylic is tested as a function of bond joint thickness. 0.125 in. thick bond joints were found to posses the maximum strength while the acceptable range of joints varied from 0.063 in. to almost 0.25 in. Such joints are used in the Sudbury Neutrino Observatory.

  12. Bond percolation in films

    Science.gov (United States)

    Korneta, W.; Pytel, Z.

    1988-04-01

    Bond percolation in films with simple cubic structure is considered. It is assumed that the probability of a bond being present between nearest-neighbor sites depends on the distances to surfaces. Based on the relation between the Potts model and the bond percolation model, and using the mean-field approximation, the phase diagram and profiles of the percolation probability have been obtained.

  13. Chemical bond fundamental aspects of chemical bonding

    CERN Document Server

    Frenking, Gernot

    2014-01-01

    This is the perfect complement to ""Chemical Bonding - Across the Periodic Table"" by the same editors, who are two of the top scientists working on this topic, each with extensive experience and important connections within the community. The resulting book is a unique overview of the different approaches used for describing a chemical bond, including molecular-orbital based, valence-bond based, ELF, AIM and density-functional based methods. It takes into account the many developments that have taken place in the field over the past few decades due to the rapid advances in quantum chemica

  14. $\\kappa$-Deformation and Spectral Triples

    CERN Document Server

    Iochum, B; Schücker, Th; Sitarz, A; 10.5506/APhysPolBSupp.4.305

    2011-01-01

    The aim of the paper is to answer the following question: does $\\kappa$-deformation fit into the framework of noncommutative geometry in the sense of spectral triples? Using a compactification of time, we get a discrete version of $\\kappa$-Minkowski deformation via $C^*$-algebras of groups. The dynamical system of the underlying groups (including some Baumslag--Solitar groups) is used in order to construct \\emph{finitely summable} spectral triples. This allows to bypass an obstruction to finite-summability appearing when using the common regular representation.

  15. Triple arthrodesis for adult acquired flatfoot.

    Science.gov (United States)

    Catanzariti, Alan R; Dix, Brian T; Richardson, Phillip E; Mendicino, Robert W

    2014-07-01

    The primary goal of triple arthrodesis for stage III and IV adult acquired flatfoot is to obtain a well-aligned plantigrade foot that will support the ankle in optimal alignment. Ancillary procedures including posterior muscle group lengthening, medial displacement calcaneal osteotomy, medial column stabilization, peroneus brevis tenotomy, or transfer and harvest of regional bone graft are often necessary to achieve adequate realignment. Image intensification is helpful in confirming optimal realignment before fixation. Results of triple arthrodesis are enhanced with adequate preparation of joint surfaces, bone graft/orthobiologics, 2-point fixation of all 3 tritarsal joints, and a vertical heel position.

  16. Molecular dynamics studies of side chain effect on the beta-1,3-D-glucan triple helix in aqueous solution.

    Science.gov (United States)

    Okobira, Tadashi; Miyoshi, Kentaro; Uezu, Kazuya; Sakurai, Kazuo; Shinkai, Seiji

    2008-03-01

    beta-1,3-D-glucans have been isolated from fungi as right-handed 6(1) triple helices. They are categorized by the side chains bound to the main triple helix through beta-(1-->6)-D-glycosyl linkage. Indeed, since a glucose-based side chain is water soluble, the presence and frequency of glucose-based side chains give rise to significant variation in the physical properties of the glucan family. Curdlan has no side chains and self-assembles to form an water-insoluble triple helical structure, while schizophyllan, which has a 1,6-D-glucose side chain on every third glucose unit along the main chain, is completely water soluble. A thermal fluctuation in the optical rotatory dispersion is observed for the side chain, indicating probable co-operative interaction between the side chains and water molecules. This paper documents molecular dynamics simulations in aqueous solution for three models of the beta-1,3-D-glucan series: curdlan (no side chain), schizophyllan (a beta-(1-->6)-D-glycosyl side-chain at every third position), and a hypothetical triple helix with a side chain at every sixth main-chain glucose unit. A decrease was observed in the helical pitch as the population of the side chain increased. Two types of hydrogen bonding via water molecules, the side chain/main chain and the side chain/side chain hydrogen bonding, play an important role in determination of the triple helix conformation. The formation of a one-dimensional cavity of diameter about 3.5 A was observed in the schizophyllan triple helix, while curdlan showed no such cavity. The side chain/side chain hydrogen bonding in schizophyllan and the hypothetical beta-1,3-D-glucan triple helix could cause the tilt of the main-chain glucose residues to the helix.

  17. Benchmarking DFT methods with small basis sets for the calculation of halogen-bond strengths.

    Science.gov (United States)

    Siiskonen, Antti; Priimagi, Arri

    2017-02-01

    In recent years, halogen bonding has become an important design tool in crystal engineering, supramolecular chemistry and biosciences. The fundamentals of halogen bonding have been studied extensively with high-accuracy computational methods. Due to its non-covalency, the use of triple-zeta (or larger) basis sets is often recommended when studying halogen bonding. However, in the large systems often encountered in supramolecular chemistry and biosciences, large basis sets can make the calculations far too slow. Therefore, small basis sets, which would combine high computational speed and high accuracy, are in great demand. This study focuses on comparing how well density functional theory (DFT) methods employing small, double-zeta basis sets can estimate halogen-bond strengths. Several methods with triple-zeta basis sets are included for comparison. Altogether, 46 DFT methods were tested using two data sets of 18 and 33 halogen-bonded complexes for which the complexation energies have been previously calculated with the high-accuracy CCSD(T)/CBS method. The DGDZVP basis set performed far better than other double-zeta basis sets, and it even outperformed the triple-zeta basis sets. Due to its small size, it is well-suited to studying halogen bonding in large systems.

  18. MEIR-KEELER TYPE CONTRACTIONS FOR TRIPLED FIXED POINTS

    Institute of Scientific and Technical Information of China (English)

    Hassen Aydi; Erdal Karapinar; Calogero Vetro

    2012-01-01

    In 2011,Berinde and Borcut [6] introduced the notion of tripled fixed point in partially ordered metric spaces.In our paper,we give some new tripled fixed point theorems by using a generalization of Meir-Keeler contraction.

  19. The triple helical structure and stability of collagen model peptide with 4(S)-hydroxyprolyl-Pro-Gly units.

    Science.gov (United States)

    Motooka, Daisuke; Kawahara, Kazuki; Nakamura, Shota; Doi, Masamitsu; Nishi, Yoshinori; Nishiuchi, Yuji; Kang, Young Kee; Nakazawa, Takashi; Uchiyama, Susumu; Yoshida, Takuya; Ohkubo, Tadayasu; Kobayashi, Yuji

    2012-01-01

    Extensive studies on the structure of collagen have revealed that the hydroxylation of Pro residues in a variety of model peptides with the typical (X-Y-Gly)(n) repeats (X and Y: Pro and its analogues) represents one of the major factors influencing the stability of triple helices. While(2S,4R)-hydroxyproline (Hyp) at the position Y stabilizes the triple helix, (2S,4S)-hydroxyproline (hyp) at the X-position destabilizes the helix as demonstrated that the triple helix of (hyp-Pro-Gly)(15) is less stable than that of (Pro-Pro-Gly)(15) and that a shorter peptide (hyp-Pro-Gly)(10) does not form the helix. To clarify the role of the hydroxyl group of Pro residues to play in the stabilization mechanism of the collagen triple helix, we synthesized and crystallized a model peptide (Pro-Hyp-Gly)(4) -(hyp-Pro-Gly)(2) -(Pro-Hyp-Gly)(4) and analyzed its structure by X-ray crystallography and CD spectroscopy. In the crystal, the main-chain of this peptide forms a typical collagen like triple helix. The majority of hyp residues take down pucker with exceptionally shallow angles probably to relieve steric hindrance, but the remainders protrude the hydroxyl group toward solvent with the less favorable up pucker to fit in a triple helix. There is no indication of the existence of an intra-molecular hydrogen bond between the hydroxyl moiety and the carbonyl oxygen of hyp supposed to destabilize the triple helix. We also compared the conformational energies of up and down packers of the pyrrolidine ring in Ac-hyp-NMe(2) by quantum mechanical calculations.

  20. Triple-axis spectrometer DruechaL

    Energy Technology Data Exchange (ETDEWEB)

    Buehrer, W.; Keller, P. [Lab. for Neutron Scattering ETH Zurich, Zurich (Switzerland) and Paul Scherrer Institute, Villigen (Switzerland)

    1996-11-01

    DruechaL is a triple-axis spectrometer located at a cold guide. The characteristics of guide and instrument allow the use of a broad spectral range of neutrons. The resolution in momentum and energy transfer can be tuned to match the experimental requirements by using either collimators or focusing systems (monochromator, antitrumpet, analyser). (author) figs., tabs., refs.

  1. Detecting Triple Systems with Gravitational Wave Observations

    Science.gov (United States)

    Meiron, Yohai; Kocsis, Bence; Loeb, Abraham

    2017-01-01

    The Laser Interferometer Gravitational Wave Observatory (LIGO) has recently discovered gravitational waves (GWs) emitted by merging black hole binaries. We examine whether future GW detections may identify triple companions of merging binaries. Such a triple companion causes variations in the GW signal due to: (1) the varying path length along the line of sight during the orbit around the center of mass; (2) relativistic beaming, Doppler, and gravitational redshift; (3) the variation of the “light”-travel time in the gravitational field of the triple companion; and (4) secular variations of the orbital elements. We find that the prospects for detecting a triple companion are the highest for low-mass compact object binaries which spend the longest time in the LIGO frequency band. In particular, for merging neutron star binaries, LIGO may detect a white dwarf or M-dwarf perturber at a signal-to-noise ratio of 8, if it is within 0.4 {R}ȯ distance from the binary and the system is within a distance of 100 Mpc. Stellar mass (supermassive) black hole perturbers may be detected at a factor 5 × (103×) larger separations. Such pertubers in orbit around a merging binary emit GWs at frequencies above 1 mHz detectable by the Laser Interferometer Space Antenna in coincidence.

  2. Detecting triple systems with gravitational wave observations

    CERN Document Server

    Meiron, Yohai; Loeb, Abraham

    2016-01-01

    The Laser Interferometer Gravitational Wave Observatory (LIGO) has recently discovered gravitational waves (GWs) emitted by merging black hole binaries. We examine whether future GW detections may identify triple companions of merging binaries. Such a triple companion causes variations in the GW signal due to (1) the varying path length along the line of sight during the orbit around the center of mass, (2) relativistic beaming, Doppler, and gravitational redshift, and (3) the variation of the "light"-travel time in the gravitational field of the triple companion, known respectively as Roemer-, Einstein-, and Shapiro-delays in pulsar binaries. We find that the prospects for detecting the triple companion are the highest for low-mass compact object binaries which spend the longest time in the LIGO frequency band with circular orbits. In particular, for merging neutron star binaries, LIGO may detect a white dwarf or M-dwarf perturber at signal to noise ratio of 8, if it is within 0.4 solar radius distance from ...

  3. Discovering Steiner Triple Systems through Problem Solving

    Science.gov (United States)

    Sriraman, Bharath

    2004-01-01

    An attempt to implement problem solving as a teacher of ninth grade algebra is described. The problems selected were not general ones, they involved combinations and represented various situations and were more complex which lead to the discovery of Steiner triple systems.

  4. Resolution of a triple axis spectrometer

    DEFF Research Database (Denmark)

    Nielsen, Mourits; Bjerrum Møller, Hans

    1969-01-01

    A new method for obtaining the resolution function for a triple-axis neutron spectrometer is described, involving a combination of direct measurement and analytical calculation. All factors which contribute to the finite resolution of the instrument may be taken into account, and Gaussian...

  5. Triple mode filters with coaxial excitation

    NARCIS (Netherlands)

    Gerini, G.; Bustamante, F.D.; Guglielmi, M.

    2004-01-01

    In this paper we describe triple mode filters in a square waveguide with integrated coaxial input/output excitation. An important feature of the structure proposed is that it is easily amenable to an accurate full wave analysis. In addition to theory, a practical six pole filter with two transmissio

  6. Revised Reynolds Stress and Triple Product Models

    Science.gov (United States)

    Olsen, Michael E.; Lillard, Randolph P.

    2017-01-01

    Revised versions of Lag methodology Reynolds-stress and triple product models are applied to accepted test cases to assess the improvement, or lack thereof, in the prediction capability of the models. The Bachalo-Johnson bump flow is shown as an example for this abstract submission.

  7. Targeting EGFR in Triple Negative Breast Cancer

    Directory of Open Access Journals (Sweden)

    Naoto T. Ueno, Dongwei Zhang

    2011-01-01

    Full Text Available Our preliminary data show that erlotinib inhibits Triple-negative breast cancer (TNBC in a xenograft model. However, inhibition of metastasis by erlotinib is accompanied by nonspecific effects because erlotinib can inhibit other kinases; thus, more direct targets that regulate TNBC metastasis need to be identified to improve its therapeutic efficacy.

  8. A reconstruction theorem for almost-commutative spectral triples

    CERN Document Server

    Ćaćić, Branimir

    2011-01-01

    We propose an expansion of the definition of almost-commutative spectral triple that accommodates non-trivial fibrations and is stable under inner fluctuation of the metric, and then prove a reconstruction theorem for almost-commutative spectral triples under this definition as a simple consequence of the reconstruction theorem for commutative spectral triples. Along the way, we weaken the orientability hypothesis in Connes's reconstruction theorem for commutative spectral triples, and, following Chakraborty and Mathai, prove a number of results concerning the stability of properties of spectral triples under suitable perturbation of the Dirac operator.

  9. Copper wire bonding

    CERN Document Server

    Chauhan, Preeti S; Zhong, ZhaoWei; Pecht, Michael G

    2014-01-01

    This critical volume provides an in-depth presentation of copper wire bonding technologies, processes and equipment, along with the economic benefits and risks.  Due to the increasing cost of materials used to make electronic components, the electronics industry has been rapidly moving from high cost gold to significantly lower cost copper as a wire bonding material.  However, copper wire bonding has several process and reliability concerns due to its material properties.  Copper Wire Bonding book lays out the challenges involved in replacing gold with copper as a wire bond material, and includes the bonding process changes—bond force, electric flame off, current and ultrasonic energy optimization, and bonding tools and equipment changes for first and second bond formation.  In addition, the bond–pad metallurgies and the use of bare and palladium-coated copper wires on aluminum are presented, and gold, nickel and palladium surface finishes are discussed.  The book also discusses best practices and re...

  10. Real structures on almost-commutative spectral triples

    CERN Document Server

    Ćaćić, Branimir

    2012-01-01

    We refine the reconstruction theorem for almost-commutative spectral triples to a result for real almost-commutative spectral triples, clarifying, in the process, both concrete and abstract definitions of real commutative and almost-commutative spectral triples. In particular, we find that a real almost-commutative spectral triple algebraically encodes the commutative *-algebra of the base manifold in a canonical way, and that a compact oriented Riemannian manifold admits real (almost-)commutative spectral triples of arbitrary KO-dimension. Moreover, we define a notion of smooth family of real finite spectral triples and of the twisting of a concrete real commutative spectral triple by such a family, with interesting KK-theoretic and gauge-theoretic implications.

  11. Thermal stability of collagen triple helix.

    Science.gov (United States)

    Xu, Yujia

    2009-01-01

    Chief among the challenges of characterizing the thermal stability of the collagen triple helix are the lack of the reversibility of the thermal transition and the presence of multiple folding-unfolding steps during the thermal transition which rarely follows the simple two-state, all-or-none mechanism. Despite of the difficulties inherited in the quantitative depiction of the thermal transition of collagen, biophysical studies combined with proteolysis and mutagenesis approaches using full-chain collagens, short synthetic peptides, and recombinant collagen fragments have revealed molecular features of the thermal unfolding of the subdomains of collagen and led to a better understanding of the diverse biological functions of this versatile protein. The subdomain of collagen generally refers to a segment of the long, rope-like triple helical molecule that can unfold cooperatively as an independent unit whose properties (their size, location, and thermal stability) are considered essential for the molecular recognition during the self-assembly of collagen and during the interactions of collagen with other macromolecules. While the unfolding of segments of the triple helix at temperatures below the apparent melting temperature of the molecule has been used to interpret much of the features of the thermal unfolding of full-chain collagens, the thermal studies of short, synthetic peptides have firmly established the molecular basis of the subdomains by clearly demonstrating the close dependence of the thermal stability of a triple helix on the constituent amino acid residues at the X and the Y positions of the characteristic Gly-X-Y repeating sequence patterns of the triple helix. Studies using recombinant collagen fragments further revealed that in the context of the long, linear molecule, the stability of a segment of the triple helix is also modulated by long-range impact of the local interactions such as the interchain salt bridges. Together, the combined approaches

  12. The lncRNA HOTAIR impacts on mesenchymal stem cells via triple helix formation.

    Science.gov (United States)

    Kalwa, Marie; Hänzelmann, Sonja; Otto, Sabrina; Kuo, Chao-Chung; Franzen, Julia; Joussen, Sylvia; Fernandez-Rebollo, Eduardo; Rath, Björn; Koch, Carmen; Hofmann, Andrea; Lee, Shih-Han; Teschendorff, Andrew E; Denecke, Bernd; Lin, Qiong; Widschwendter, Martin; Weinhold, Elmar; Costa, Ivan G; Wagner, Wolfgang

    2016-12-15

    There is a growing perception that long non-coding RNAs (lncRNAs) modulate cellular function. In this study, we analyzed the role of the lncRNA HOTAIR in mesenchymal stem cells (MSCs) with particular focus on senescence-associated changes in gene expression and DNA-methylation (DNAm). HOTAIR binding sites were enriched at genomic regions that become hypermethylated with increasing cell culture passage. Overexpression and knockdown of HOTAIR inhibited or stimulated adipogenic differentiation of MSCs, respectively. Modification of HOTAIR expression evoked only very moderate effects on gene expression, particularly of polycomb group target genes. Furthermore, overexpression and knockdown of HOTAIR resulted in DNAm changes at HOTAIR binding sites. Five potential triple helix forming domains were predicted within the HOTAIR sequence based on reverse Hoogsteen hydrogen bonds. Notably, the predicted triple helix target sites for these HOTAIR domains were also enriched in differentially expressed genes and close to DNAm changes upon modulation of HOTAIR Electrophoretic mobility shift assays provided further evidence that HOTAIR domains form RNA-DNA-DNA triplexes with predicted target sites. Our results demonstrate that HOTAIR impacts on differentiation of MSCs and that it is associated with senescence-associated DNAm. Targeting of epigenetic modifiers to relevant loci in the genome may involve triple helix formation with HOTAIR.

  13. Secular Evolution of Hierarchical Triple Star Systems

    CERN Document Server

    Ford, E B; Kozinsky, B

    1999-01-01

    We derive octupole-level secular perturbation equations for hierarchical triple systems, using classical Hamiltonian perturbation techniques. Our equations describe the secular evolution of the orbital eccentricities and inclinations over timescales long compared to the orbital periods. By extending previous work done to leading (quadrupole) order to octupole level (i.e., including terms of order $\\alpha^3$, where $\\alpha\\equiv a_1/a_2<1$ is the ratio of semimajor axes) we obtain expressions that are applicable to a much wider range of parameters. For triple systems containing a close inner binary, we also discuss the possible interaction between the classical Newtonian perturbations and the general relativistic precession of the inner orbit. In some cases we show that this interaction can lead to resonances and a significant increase in the maximum amplitude of eccentricity perturbations. We establish the validity of our analytic expressions by providing detailed comparisons with the results of direct num...

  14. Triple A Syndrome: A Case Report

    Directory of Open Access Journals (Sweden)

    Murat Atmaca

    2014-09-01

    Full Text Available Triple A syndrome is a rarely seen autosomal recessive disease characterized by achalasia, adrenal failure and alacrima. The syndrome is frequently seen in childhood. The appearance of its components are usually ordered as alacrima, achalasia and adrenal failure. The majority of the patients diagnosed in the later stages predominantly present with neurological symptoms. In this study, a 21-year-old male who was referred to our clinic with clinical findings of chronic adrenal failure and was diagnosed WİTH triple A syndrome is presented. This patient had been operated three years ago due to achalasia. The diagnosis and treatment of adrenal failure in this syndrome is the most important determinant and indicator in the prognosis of the disease. Turk Jem 2014; 18: 97-99

  15. On Triple-Cut of Scattering Amplitudes

    CERN Document Server

    Mastrolia, Pierpaolo

    2007-01-01

    It is analysed the triple-cut of one-loop amplitudes in dimensional regularisation within spinor-helicity representation. The triple-cut is defined as a difference of two double-cuts with the same particle content, and a same propagator carrying, respectively, causal and anti-causal prescription in each of the two cuts. That turns out into an effective tool for extracting the coefficients of the three-point functions (and higher-point ones) from one-loop-amplitudes. The phase-space integration is oversimplified by using residues theorem to perform the integration over the spinor variables, via the holomorphic anomaly, and a trivial integration on the Feynman parameter. The results are valid for arbitrary values of dimensions.

  16. Comparison of Gold Bonding with Mercury Bonding

    NARCIS (Netherlands)

    Kraka, Elfi; Filatov, Michael; Cremer, Dieter

    2009-01-01

    Nine AuX molecules (X = H, O, S, Se, Te, F, Cl, Br, I), their isoelectronic HgX(+) analogues, and the corresponding neutral HgX diatomics have been investigated using NESC (Normalized Elimination of the Small Component) and B3LYP theory to determine relativistic effects for bond dissociation energie

  17. Triple Teeth: Report of an Unusual Case

    OpenAIRE

    Prashant Babaji; M. A. Prasanth; Gowda, Ajith R.; Soumya Ajith; Henston D'Souza; Ashok, K. P.

    2012-01-01

    Fusion or synodontia is a union of two or more than two developing teeth. Commonly fusion occurs between teeth of the same dentition, mixed dentition, or between normal and supernumerary teeth. Fused primary teeth present with several clinical problems like caries, periodontal problem, arch asymmetry, delayed eruption, ectopic eruption of succedaneous teeth, aesthetic, and other complications. This paper presents a rare and unusual case of triple teeth in mandibular primary dentition.

  18. Triple Teeth: Report of an Unusual Case

    Directory of Open Access Journals (Sweden)

    Prashant Babaji

    2012-01-01

    Full Text Available Fusion or synodontia is a union of two or more than two developing teeth. Commonly fusion occurs between teeth of the same dentition, mixed dentition, or between normal and supernumerary teeth. Fused primary teeth present with several clinical problems like caries, periodontal problem, arch asymmetry, delayed eruption, ectopic eruption of succedaneous teeth, aesthetic, and other complications. This paper presents a rare and unusual case of triple teeth in mandibular primary dentition.

  19. Mordell-Weil groups and Zariski triples

    CERN Document Server

    Cogolludo-Agustin, Jose Ignacio

    2011-01-01

    We prove the existence of three irreducible curves $C_{12,m}$ of degree 12 with the same number of cusps and different Alexander polynomials. This exhibits a Zariski triple. Moreover we provide a set of generators for the elliptic threefold with constant $j$-invariant 0 and discriminant curve $C_{12,m}$. Finally we consider general degree $d$ base change of $C_{12d,m}$ and calculate the dimension of the equisingular deformation space.

  20. Triple plasmon resonance of bimetal nanoshell

    Energy Technology Data Exchange (ETDEWEB)

    Shirzaditabar, Farzad [Department of Physics, Razi University, Kermanshah (Iran, Islamic Republic of); Saliminasab, Maryam, E-mail: m.saliminasab@yahoo.com [Young Researchers Club, Kermanshah Branch, Islamic Azad University, Kermanshah (Iran, Islamic Republic of); Arghavani Nia, Borhan [Department of Physics, Kermanshah Branch, Islamic Azad University, Kermanshah (Iran, Islamic Republic of)

    2014-07-15

    In this paper, light absorption spectra properties of a bimetal multilayer nanoshell based on quasi-static approach are investigated. Comparing with silver-dielectric-silver and silver-dielectric-gold nanoshells, gold-dielectric-silver nanoshells have three intense and separated plasmon peaks which are more suitable for multiplex biosensing. Calculations show that relatively small thickness of outer silver shell and large dielectric constant of middle dielectric layer of gold-dielectric-silver nanoshell are suitable to obtain the triple plasmon resonance.

  1. Triple plasmon resonance of bimetal nanoshell

    Science.gov (United States)

    Shirzaditabar, Farzad; Saliminasab, Maryam; Arghavani Nia, Borhan

    2014-07-01

    In this paper, light absorption spectra properties of a bimetal multilayer nanoshell based on quasi-static approach are investigated. Comparing with silver-dielectric-silver and silver-dielectric-gold nanoshells, gold-dielectric-silver nanoshells have three intense and separated plasmon peaks which are more suitable for multiplex biosensing. Calculations show that relatively small thickness of outer silver shell and large dielectric constant of middle dielectric layer of gold-dielectric-silver nanoshell are suitable to obtain the triple plasmon resonance.

  2. The dissociative bond.

    Science.gov (United States)

    Gordon, Nirit

    2013-01-01

    Dissociation leaves a psychic void and a lingering sense of psychic absence. How do 2 people bond while they are both suffering from dissociation? The author explores the notion of a dissociative bond that occurs in the aftermath of trauma--a bond that holds at its core an understanding and shared detachment from the self. Such a bond is confined to unspoken terms that are established in the relational unconscious. The author proposes understanding the dissociative bond as a transitional space that may not lead to full integration of dissociated knowledge yet offers some healing. This is exemplified by R. Prince's (2009) clinical case study. A relational perspective is adopted, focusing on the intersubjective aspects of a dyadic relationship. In the dissociative bond, recognition of the need to experience mutual dissociation can accommodate a psychic state that yearns for relationship when the psyche cannot fully confront past wounds. Such a bond speaks to the need to reestablish a sense of human relatedness and connection when both parties in the relationship suffer from disconnection. This bond is bound to a silence that becomes both a means of protection against the horror of traumatic memory and a way to convey unspoken gestures toward the other.

  3. Stereoelectronic and steric effects in the collagen triple helix: toward a code for strand association.

    Science.gov (United States)

    Hodges, Jonathan A; Raines, Ronald T

    2005-11-16

    Collagen is the most abundant protein in animals. The protein consists of a helix of three strands, each with sequence X-Y-Gly. Natural collagen is most stable when X is (2S)-proline (Pro) and Y is (2S,4R)-4-hydroxyproline (4R-Hyp). We had shown previously that triple helices in which X is (2S,4S)-4-fluoroproline (4S-Flp) or Y is (2S,4R)-4-fluoroproline (4R-Flp) display hyperstability. This hyperstability arises from stereoelectronic effects that preorganize the main-chain dihedral angles in the conformation found in the triple helix. Here, we report the synthesis of strands containing both 4S-Flp in the X-position and 4R-Flp in the Y-position. We find that these strands do not form a stable triple helix, presumably because of an unfavorable steric interaction between fluoro groups on adjacent strands. Density functional theory calculations indicate that (2S,3S)-3-fluoroproline (3S-Flp), like 4S-Flp, should preorganize the main chain properly for triple-helix formation but without a steric conflict. Synthetic strands containing 3S-Flp in the X-position and 4R-Flp in the Y-position do form a triple helix. This helix is, however, less stable than one with Pro in the X-position, presumably because of an unfavorable inductive effect that diminishes the strength of the interstrand 3S-FlpC=O...H-NGly hydrogen bond. Thus, other forces can counter the benefits derived from the proper preorganization. Although (Pro-Pro-Gly)7 and (4S-Flp-4R-Flp-Gly)7 do not form stable homotrimeric helices, mixtures of these two peptides form stable heterotrimeric helices containing one (Pro-Pro-Gly)7 strand and two (4S-Flp-4R-Flp-Gly)7 strands. This stoichiometry can be understood by considering the cross sections of the two possible heterotrimeric helices. This unexpected finding portends the development of a "code" for the self-assembly of determinate triple helices from two or three strands.

  4. Effect of ultrasonic power and bonding force on the bonding strength of copper ball bonds

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Copper wire, serving as a cost-saving alternative to gold wire, has been used in many high-end thermosonic ball bonding applications. In this paper, the bond shear force, bond shear strength, and the ball bond diameter are adopted to evaluate the bonding quality. It is concluded that the efficient ultrasonic power is needed to soften the ball to form the copper bonds with high bonding strength. However, excessive ultrasonic power would serve as a fatigue loading to weaken the bonding. Excessive or less bonding force would cause cratering in the silicon.

  5. Transversely Compressed Bonded Joints

    DEFF Research Database (Denmark)

    Hansen, Christian Skodborg; Schmidt, Jacob Wittrup; Stang, Henrik

    2012-01-01

    The load capacity of bonded joints can be increased if transverse pressure is applied at the interface. The transverse pressure is assumed to introduce a Coulomb-friction contribution to the cohesive law for the interface. Response and load capacity for a bonded single-lap joint was derived using...... non-linear fracture mechanics. The results indicated a good correlation between theory and tests. Furthermore, the model is suggested as theoretical base for determining load capacity of bonded anchorages with transverse pressure, in externally reinforced concrete structures....

  6. Measurement of the second-order hyperpolarizability of the collagen triple helix and determination of its physical origin.

    Science.gov (United States)

    Deniset-Besseau, Ariane; Duboisset, Julien; Benichou, Emmanuel; Hache, François; Brevet, Pierre-François; Schanne-Klein, Marie-Claire

    2009-10-08

    We performed Hyper-Rayleigh Scattering (HRS) experiments to measure the second-order nonlinear optical response of the collagen triple helix and determine the physical origin of second harmonic signals observed in collagenous tissues. HRS experiments yielded a second-order hyperpolarizability of 1.25 x 10(-27) esu for rat-tail type I collagen, a surprisingly large value considering that collagen presents no strong harmonophore in its amino acid sequence. Polarization-resolved experiments showed intramolecular coherent contributions to the HRS signal along with incoherent contributions that are the only contributions for molecules with dimensions much smaller than the excitation wavelength. We therefore modeled the effective second-order hyperpolarizability of the 290 nm long collagen triple helix by summing coherently the nonlinear response of well-aligned moieties along the triple helix axis. This model was confirmed by HRS measurements after denaturation of the collagen triple helix and for a collagen-like short model peptide [(Pro-Pro-Gly)(10)](3). We concluded that the large collagen nonlinear response originates in the tight alignment of a large number of small and weakly efficient harmonophores, presumably the peptide bonds, resulting in a coherent amplification of the nonlinear signal.

  7. Moduli spaces of Dirac operators for finite spectral triples

    CERN Document Server

    Ćaćić, Branimir

    2009-01-01

    The structure theory of finite real spectral triples developed by Krajewski and by Paschke and Sitarz is generalised to allow for arbitrary KO-dimension and the failure of orientability and Poincare duality, and moduli spaces of Dirac operators for such spectral triples are defined and studied. This theory is then applied to recent work by Chamseddine and Connes towards deriving the finite spectral triple of the noncommutative-geometric Standard Model.

  8. Geometrical theory of triple junctions of CSL boundaries.

    Science.gov (United States)

    Gertsman, V Y

    2001-07-01

    When three grain boundaries having misorientations generating coincidence site lattices (CSLs) meet at a triple junction, a common (triple-junction) CSL is formed. A theory is developed as a set of theorems establishing the relationships between the geometrical parameters of the grain-boundary and triple-junction CSLs. Application of the theory is demonstrated in detail for the case of the cubic crystal system. It is also shown how the theory can be extended to an arbitrary crystal lattice.

  9. The emerging role of triple helices in RNA biology.

    Science.gov (United States)

    Conrad, Nicholas K

    2014-01-01

    The ability of RNA to form sophisticated secondary and tertiary structures enables it to perform a wide variety of cellular functions. One tertiary structure, the RNA triple helix, was first observed in vitro over 50 years ago, but biological activities for triple helices are only beginning to be appreciated. The recent determination of several RNA structures has implicated triple helices in distinct biological functions. For example, the SAM-II riboswitch forms a triple helix that creates a highly specific binding pocket for S-adenosylmethionine. In addition, a triple helix in the conserved pseudoknot domain of the telomerase-associated RNA TER is essential for telomerase activity. A viral RNA cis-acting RNA element called the ENE contributes to the nuclear stability of a viral noncoding RNA by forming a triple helix with the poly(A) tail. Finally, a cellular noncoding RNA, MALAT1, includes a triple helix at its 3'-end that contributes to RNA stability, but surprisingly also supports translation. These examples highlight the diverse roles that RNA triple helices play in biology. Moreover, the dissection of triple helix mechanisms has the potential to uncover fundamental pathways in cell biology.

  10. Handbook of wafer bonding

    CERN Document Server

    Ramm, Peter; Taklo, Maaike M V

    2011-01-01

    Written by an author and editor team from microsystems companies and industry-near research organizations, this handbook and reference presents dependable, first-hand information on bonding technologies.In the first part, researchers from companies and institutions around the world discuss the most reliable and reproducible technologies for the production of bonded wafers. The second part is devoted to current and emerging applications, including microresonators, biosensors and precise measuring devices.

  11. Secular Evolution of Hierarchical Triple Star Systems

    Science.gov (United States)

    Ford, Eric B.; Kozinsky, Boris; Rasio, Frederic A.

    2000-05-01

    We derive octupole-level secular perturbation equations for hierarchical triple systems, using classical Hamiltonian perturbation techniques. Our equations describe the secular evolution of the orbital eccentricities and inclinations over timescales that are long compared to the orbital periods. By extending previous work done to leading (quadrupole) order to octupole level (i.e., including terms of order α3, where α≡a1/a2quadrupole-level theory of Kozai gives a vanishing result in the limit of zero relative inclination. The classical planetary perturbation theory, while valid to all orders in α, applies only to orbits of low-mass objects orbiting a common central mass, with low eccentricities and low relative inclinations. For triple systems containing a close inner binary, we also discuss the possible interaction between the classical Newtonian perturbations and the general relativistic precession of the inner orbit. In some cases we show that this interaction can lead to resonances and a significant increase in the maximum amplitude of eccentricity perturbations. We establish the validity of our analytic expressions by providing detailed comparisons with the results of direct numerical integrations of the three-body problem obtained for a large number of representative cases. In addition, we show that our expressions reduce correctly to previously published analytic results obtained in various limiting regimes. We also discuss applications of the theory in the context of several observed triple systems of current interest, including the millisecond pulsar PSR B1620-26 in M4, the giant planet in 16 Cygni, and the protostellar binary TMR-1.

  12. Local index formula and twisted spectral triples

    CERN Document Server

    Moscovici, Henri

    2009-01-01

    We prove a local index formula for a class of twisted spectral triples of type III modeled on the transverse geometry of conformal foliations with locally constant transverse conformal factor. Compared with the earlier proof of the untwisted case, the novel aspect resides in the fact that the twisted analogues of the JLO entire cocycle and of its retraction are no longer cocycles in their respective Connes bicomplexes. We show however that the passage to the infinite temperature limit, respectively the integration along the full temperature range against the Haar measure of the positive half-line, has the remarkable effect of curing in both cases the deviations from the cocycle identity.

  13. Gleason's Theorem for Rectangular JBW-Triples

    Science.gov (United States)

    Edwards, C. Martin; Rüttimann, Gottfried T.

    A JBW*-triple B is said to be rectangular if there exists a W*-algebra A and a pair (p,q) of centrally equivalent elements of the complete orthomodular lattice of projections in A such that B is isomorphic to the JBW*-triple pAq. Any weak*-closed injective operator space provides an example of a rectangular JBW*-triple. The principal order ideal of the complete *-lattice of centrally equivalent pairs of projections in a W*-algebra A, generated by (p,q), forms a complete lattice that is order isomorphic to the complete lattice of weak*-closed inner ideals in B and to the complete lattice of structural projections on B. Although not itself, in general, orthomodular, possesses a complementation that allows for definitions of orthogonality, centre, and central orthogonality to be given. A less familiar notion in lattice theory, that is well-known in the theory of Jordan algebras and Jordan triple systems, is that of rigid collinearity of a pair (e2,f2) and (e2,f2) of elements of . This is defined and characterized in terms of properties of . A W*-algebra A is sometimes thought of as providing a model for a statistical physical system. In this case B, or, equivalently, pAq, may be thought of as providing a model for a fixed sub-system of that represented by A. Therefore, may be considered to represent the set consisting of a particular kind of sub-system of that represented by pAq. Central orthogonality and rigid collinearity of pairs of elements of may be regarded as representing two different types of disjointness, the former, classical disjointness, and the latter, decoherence, of the two sub-systems. It is therefore natural to consider bounded measures m on that are additive on centrally orthogonal and rigidly collinear pairs of elements. Using results of J.D.M. Wright, it is shown that, provided that neither of the two hereditary sub-W*-algebras pAp and qAq of A has a weak*-closed ideal of Type I2, such measures are precisely those that are the restrictions of

  14. Vectorized data acquisition and fast triple-correlation integrals for Fluorescence Triple Correlation Spectroscopy.

    Science.gov (United States)

    Ridgeway, William K; Millar, David P; Williamson, James R

    2013-04-01

    Fluorescence Correlation Spectroscopy (FCS) is widely used to quantitate reaction rates and concentrations of molecules in vitro and in vivo. We recently reported Fluorescence Triple Correlation Spectroscopy (F3CS), which correlates three signals together instead of two. F3CS can analyze the stoichiometries of complex mixtures and detect irreversible processes by identifying time-reversal asymmetries. Here we report the computational developments that were required for the realization of F3CS and present the results as the Triple Correlation Toolbox suite of programs. Triple Correlation Toolbox is a complete data analysis pipeline capable of acquiring, correlating and fitting large data sets. Each segment of the pipeline handles error estimates for accurate error-weighted global fitting. Data acquisition was accelerated with a combination of off-the-shelf counter-timer chips and vectorized operations on 128-bit registers. This allows desktop computers with inexpensive data acquisition cards to acquire hours of multiple-channel data with sub-microsecond time resolution. Off-line correlation integrals were implemented as a two delay time multiple-tau scheme that scales efficiently with multiple processors and provides an unprecedented view of linked dynamics. Global fitting routines are provided to fit FCS and F3CS data to models containing up to ten species. Triple Correlation Toolbox is a complete package that enables F3CS to be performed on existing microscopes.

  15. Clicking the Arsenic-Carbon Triple Bond: An Entry into a New Class of Arsenic Heterocycles.

    Science.gov (United States)

    Pfeifer, Gregor; Papke, Martin; Frost, Daniel; Sklorz, Julian A W; Habicht, Marija; Müller, Christian

    2016-09-19

    Arsaalkynes can undergo regioselective and quantitative [3+2] cycloaddition reactions with organic azides to give hitherto unknown 3H-1,2,3,4-triazaarsole derivatives. The reaction product was obtained as a white, air- and moisture-stable solid, and the presence of a planar, five-membered arsenic heterocycle was unambiguously verified by means of X-ray crystallography. DFT calculations gave insight into the electronic structure of these novel compounds compared to tetrazoles and triazaphospholes. The coordination chemistry towards Re(I) was investigated and compared with the structurally related phosphorus-containing ligand. These preliminary investigations pave the way for a new class of arsenic heterocycles and fill the gap between the azaarsoles already known.

  16. Recovery and normalization of triple coincidences in PET

    Energy Technology Data Exchange (ETDEWEB)

    Lage, Eduardo, E-mail: elage@mit.edu; Parot, Vicente; Dave, Shivang R.; Herraiz, Joaquin L. [Madrid-MIT M+Visión Consortium, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Moore, Stephen C.; Sitek, Arkadiusz; Park, Mi-Ae [Division of Nuclear Medicine, Department of Radiology, Harvard Medical School and Brigham and Women’s Hospital, Boston, Massachusetts 02115 (United States); Udías, Jose M. [Grupo de Física Nuclear, Departamento de Física Atómica Molecular y Nuclear, Universidad Complutense de Madrid, CEI Moncloa, Madrid 28040 (Spain); Vaquero, Juan J. [Departamento de Ingeniería Biomédica e Ingeniería Aeroespacial, Universidad Carlos III de Madrid, Leganés 28911 (Spain)

    2015-03-15

    Purpose: Triple coincidences in positron emission tomography (PET) are events in which three γ-rays are detected simultaneously. These events, though potentially useful for enhancing the sensitivity of PET scanners, are discarded or processed without special consideration in current systems, because there is not a clear criterion for assigning them to a unique line-of-response (LOR). Methods proposed for recovering such events usually rely on the use of highly specialized detection systems, hampering general adoption, and/or are based on Compton-scatter kinematics and, consequently, are limited in accuracy by the energy resolution of standard PET detectors. In this work, the authors propose a simple and general solution for recovering triple coincidences, which does not require specialized detectors or additional energy resolution requirements. Methods: To recover triple coincidences, the authors’ method distributes such events among their possible LORs using the relative proportions of double coincidences in these LORs. The authors show analytically that this assignment scheme represents the maximum-likelihood solution for the triple-coincidence distribution problem. The PET component of a preclinical PET/CT scanner was adapted to enable the acquisition and processing of triple coincidences. Since the efficiencies for detecting double and triple events were found to be different throughout the scanner field-of-view, a normalization procedure specific for triple coincidences was also developed. The effect of including triple coincidences using their method was compared against the cases of equally weighting the triples among their possible LORs and discarding all the triple events. The authors used as figures of merit for this comparison sensitivity, noise-equivalent count (NEC) rates and image quality calculated as described in the NEMA NU-4 protocol for the assessment of preclinical PET scanners. Results: The addition of triple-coincidence events with the

  17. Mergers and obliquities in stellar triples

    Energy Technology Data Exchange (ETDEWEB)

    Naoz, Smadar [Harvard Smithsonian Center for Astrophysics, Institute for Theory and Computation, 60 Garden Street, Cambridge, MA 02138 (United States); Fabrycky, Daniel C., E-mail: snaoz@cfa.harvard.edu [Department of Astronomy and Astrophysics, University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637 (United States)

    2014-10-01

    Many close stellar binaries are accompanied by a faraway star. The 'eccentric Kozai-Lidov' (EKL) mechanism can cause dramatic inclination and eccentricity fluctuations, resulting in tidal tightening of inner binaries of triple stars. We run a large set of Monte Carlo simulations, including the secular evolution of the orbits, general relativistic precession, and tides, and we determine the semimajor axis, eccentricity, inclination, and spin-orbit angle distributions of the final configurations. We find that the efficiency of forming tight binaries (≲ 16 days) when taking the EKL mechanism into account is ∼21%, and about 4% of all simulated systems ended up in a merger event. These merger events can lead to the formation of blue stragglers. Furthermore, we find that the spin-orbit angle distribution of the inner binaries carries a signature of the initial setup of the system; thus, observations can be used to disentangle close binaries' birth configuration. The resulting inner and outer final orbits' period distributions and their estimated fraction suggest that secular dynamics may be a significant channel for the formation of close binaries in triples and even blue stragglers.

  18. VERITAS: Versatile Triple-Axis Spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sung Il

    2006-04-15

    Korea Atomic Energy Research Institute is planning to build a cold neutron triple-axis spectrometer at HANARO, the 30 MW research reactor. The spectrometer is expected to be completed in 2008 with the following configuration from the upstream to the downstream. Guide Supermirror m = 2, In-pile Straight Section, {approx} 5 m Curved Guide, {approx} 26 m w/ R 1500 m Straight Guide before the Instrument, {approx} 40 m Filters PG and Be Neutron Velocity Selector (Future) Monochromators Vertically Focusing Monochromators PG(002) and Heusler(111) Doubly Focusing Monochromators (Future) Monochromator-Sample Distance 2 m Collimation C1 Soller Collimators, 20', 40' 80'Beam Height at the Sample Table 1.5 m Sample-Analyzer Distance 1.0 m Collimation C2 Soller Collimators, 20', 40', 80' Radial Collimator Analyzers Horizontally Focusing Analyzers w/ Fixed Vertical Focusing PG(002) and Heusler(111) Analyzer-Detector Distance 0.5 m Detectors 5 cm Tube Detector 25 cm wide Position Sensitive Detector Once completed, the neutron flux at sample is expected to surpass that of SPINS at NCNR, making this instrument one of the most powerful 2nd generation cold neutron triple-axis spectrometers in the world.

  19. Fundamentals of fiber bonding in thermally point-bonded nonwovens

    Science.gov (United States)

    Chidambaram, Aparna

    Thermal point bonding (TPB) uses heat and pressure to bond a web of fibers at discrete points imparting strength to the manufactured fabric. This process significantly reduces the strength and elongation of the bridging fibers between bond points while strengthening the web. Single fiber experiments were performed with four structurally different polypropylene fibers to analyze the inter-relationships between fiber structure, fiber properties and bonding process. Two fiber types had a low birefringence sheath or surface layer while the remaining had uniform birefringence profiles through their thickness. Bonds were formed between isolated pairs of fibers by subjecting the fibers to a calendering process and simulating TPB process conditions. The dependence of bond strength on bonding temperature and on the type of fiber used was evaluated. Fiber strengths before and after bonding were measured and compared to understand the effect of bonding on fiber strength. Additionally, bonded fiber strength was compared to the strength of single fibers which had experienced the same process conditions as the bonded pairs. This comparison estimated the effect of mechanical damage from pressing fibers together with steel rolls while creating bonds in TPB. Interfiber bond strength increased with bonding temperature for all fiber types. Fiber strength decreased with increasing bonding temperature for all fiber types except for one type of low birefringent sheath fibers. Fiber strength degradation was unavoidable at temperatures required for successful bonding. Mechanical damage from compression of fibers between rolls was an insignificant factor in this strength loss. Thermal damage during bonding was the sole significant contributor to fiber strength degradation. Fibers with low birefringence skins formed strong bonds with minimal fiber strength loss and were superior to fibers without such surface layers in TPB performance. A simple model to predict the behavior of a two-bond

  20. Modelling longevity bonds: Analysing the Swiss Re Kortis bond

    OpenAIRE

    2015-01-01

    A key contribution to the development of the traded market for longevity risk was the issuance of the Kortis bond, the world's first longevity trend bond, by Swiss Re in 2010. We analyse the design of the Kortis bond, develop suitable mortality models to analyse its payoff and discuss the key risk factors for the bond. We also investigate how the design of the Kortis bond can be adapted and extended to further develop the market for longevity risk.

  1. BROWN DWARF BINARIES FROM DISINTEGRATING TRIPLE SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    Reipurth, Bo [Institute for Astronomy and NASA Astrobiology Institute University of Hawaii, 640 N. Aohoku Place, Hilo, HI 96720 (United States); Mikkola, Seppo, E-mail: reipurth@ifa.hawaii.edu, E-mail: Seppo.Mikkola@utu.fi [Tuorla Observatory, University of Turku, Väisäläntie 20, Piikkiö (Finland)

    2015-04-15

    Binaries in which both components are brown dwarfs (BDs) are being discovered at an increasing rate, and their properties may hold clues to their origin. We have carried out 200,000 N-body simulations of three identical stellar embryos with masses drawn from a Chabrier IMF and embedded in a molecular core. The bodies are initially non-hierarchical and undergo chaotic motions within the cloud core, while accreting using Bondi–Hoyle accretion. The coupling of dynamics and accretion often leads to one or two dominant bodies controlling the center of the cloud core, while banishing the other(s) to the lower-density outskirts, leading to stunted growth. Eventually each system transforms either to a bound hierarchical configuration or breaks apart into separate single and binary components. The orbital motion is followed for 100 Myr. In order to illustrate 200,000 end-states of such dynamical evolution with accretion, we introduce the “triple diagnostic diagram,” which plots two dimensionless numbers against each other, representing the binary mass ratio and the mass ratio of the third body to the total system mass. Numerous freefloating BD binaries are formed in these simulations, and statistical properties are derived. The separation distribution function is in good correspondence with observations, showing a steep rise at close separations, peaking around 13 AU and declining more gently, reaching zero at separations greater than 200 AU. Unresolved BD triple systems may appear as wider BD binaries. Mass ratios are strongly peaked toward unity, as observed, but this is partially due to the initial assumptions. Eccentricities gradually increase toward higher values, due to the lack of viscous interactions in the simulations, which would both shrink the orbits and decrease their eccentricities. Most newborn triple systems are unstable and while there are 9209 ejected BD binaries at 1 Myr, corresponding to about 4% of the 200,000 simulations, this number has grown to

  2. Bond length, dipole moment, and harmonic frequency of CO

    Science.gov (United States)

    Barnes, Leslie A.; Liu, Bowen; Lindh, Roland

    1993-01-01

    A detailed comparison of some properties of CO is given, at the modified coupled-pair functional, single and double excitation coupled-cluster (CCSD), and CCSD(T) levels of theory (including a perturbational estimate for connected triple excitations), using a variety of basis sets. With very large one-particle basis sets, the CCSD(T) method gives excellent results for the bond distance, dipole moment, and harmonic frequency of CO. In a (6s 5p 4d 3f 2g 1h) + (1s 1p 1d) basis set, the bond distance is about 0.005a0 too large, the dipole moment about 0.005 a.u. too small, and the frequency about 6/cm too small, when compared with experimental results.

  3. Romanian government bond market

    Directory of Open Access Journals (Sweden)

    Cornelia POP

    2012-12-01

    Full Text Available The present paper aims to present the level of development reached by Romanian government bond market segment, as part of the country financial market. The analysis will be descriptive (the data series available for Romania are short, based on the secondary data offered by the official bodies involved in the process of issuing and trading the Romanian government bonds (Romanian Ministry of Public Finance, Romanian National Bank and Bucharest Stock Exchange, and also on secondary data provided by the Federation of European Stock Exchanges.To enhance the market credibility as a benchmark, a various combination of measures is necessary; among these measures are mentioned: the extension of the yield curve; the issuance calendars in order to improve transparency; increasing the disclosure of information on public debt issuance and statistics; holding regular meetings with dealers, institutional investors and rating agencies; introducing a system of primary dealers; establishing a repurchase (repo market in the government bond market. These measures will be discussed based on the evolution presented inside the paper.The paper conclude with the fact that, until now, the Romanian government bond market did not provide a benchmark for the domestic financial market and that further efforts are needed in order to increase the government bond market transparency and liquidity.

  4. Government and Governance of Regional Triple Helix Interactions

    Science.gov (United States)

    Danson, Mike; Todeva, Emanuela

    2016-01-01

    This conceptual paper contributes to the discussion of the role of regional government and regional Triple Helix constellations driving economic development and growth within regional boundaries. The impact of regionalism and subsidiarity on regional Triple Helix constellations, and the questions of governmentality, governance and institutional…

  5. The triple pomeron interaction in the perturbative QCD

    CERN Document Server

    Braun, M

    1995-01-01

    The triple pomeron interaction is studied in the perturbative approach of BFKL-Bartels. At finite momentum transfers \\sqrt{-t} the contribution factorizes in the standard manner with a triple-pomeron vertex proportional to 1/\\sqrt{-t}. At t=0 the contribution is finite, although it grows faster with energy than for finite t and does not factorize.

  6. Fibonacci-triple sequences and some fundamental properties

    Directory of Open Access Journals (Sweden)

    Bijendra Singh

    2010-12-01

    Full Text Available Fibonacci sequence stands as a kind of super sequence with fabulous properties. This note presents Fibonacci-Triple sequences that may also be called 3-F sequences. This is the explosive development in the region of Fibonacci sequence. Our purpose of this paper is to demonstrate fundamental properties of Fibonacci-Triple sequence.

  7. The Triple Jump: Assessing Problem Solving in Psychiatry.

    Science.gov (United States)

    O'Gorman, Ethna C.; Trimble, Peter; Smyth, Joe

    1998-01-01

    Describes an attempt to assess a final-year course in psychiatry using the Triple Jump. In this course, students on placement in psychiatric units perfect psychiatry skills that were acquired during the previous year by direct contact with patients. The Triple Jump is used to assess problem-solving skills in management strategy on cases. (PVD)

  8. A canonical trace associated with certain spectral triples

    CERN Document Server

    Paycha, Sylvie

    2010-01-01

    In the abstract pseudodifferential set up of Connes and Moscovici, we prove a general formula for discrepancies of zeta-regularised traces associated with certain spectral triples and we introduce a canonical trace on operators whose order lies outside (minus) the dimension spectrum of the spectral triple.

  9. A Canonical Trace Associated with Certain Spectral Triples

    Directory of Open Access Journals (Sweden)

    Sylvie Paycha

    2010-09-01

    Full Text Available In the abstract pseudodifferential setup of Connes and Moscovici, we prove a general formula for the discrepancies of zeta-regularised traces associated with certain spectral triples, and we introduce a canonical trace on operators, whose order lies outside (minus the dimension spectrum of the spectral triple.

  10. A Canonical Trace Associated with Certain Spectral Triples

    Science.gov (United States)

    Paycha, Sylvie

    2010-09-01

    In the abstract pseudodifferential setup of Connes and Moscovici, we prove a general formula for the discrepancies of zeta-regularised traces associated with certain spectral triples, and we introduce a canonical trace on operators, whose order lies outside (minus) the dimension spectrum of the spectral triple.

  11. Outcome Measures of Triple Board Graduates, 1991-2003

    Science.gov (United States)

    Warren, Marla J.; Dunn, David W.; Rushton, Jerry

    2006-01-01

    Objective: To describe program outcomes for the Combined Training Program in Child and Adolescent Psychiatry, Pediatrics, and Psychiatry (Triple Board Program). Method: All Triple Board Program graduates to date (1991-2003) were asked to participate in a 37-item written survey from February to April 2004. Results: The response rate was 80.7%. Most…

  12. Reverse triple I method of restriction for fuzzy reasoning

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A theory of reverse triple I method of restriction for implication operator R0 is proposed.And the general computation formulas of infimum for fuzzy modus ponens and supremum for fuzzy modus tollens of a-reverse triple I method of restriction are obtained respectively.

  13. "Special Issue": Regional Dimensions of the Triple Helix Model

    Science.gov (United States)

    Todeva, Emanuela; Danson, Mike

    2016-01-01

    This paper introduces the rationale for the special issue and its contributions, which bridge the literature on regional development and the Triple Helix model. The concept of the Triple Helix at the sub-national, and specifically regional, level is established and examined, with special regard to regional economic development founded on…

  14. Regional Dimensions of the Triple Helix Model: Setting the Context

    Science.gov (United States)

    Todeva, Emanuela; Danson, Mike

    2016-01-01

    This paper introduces the rationale for the special issue and its contributions, which bridge the literature on regional development and the Triple Helix model. The concept of the Triple Helix at the sub-national, and specifically regional, level is established and examined, with special regard to regional economic development founded on…

  15. On Twisting Real Spectral Triples by Algebra Automorphisms

    Science.gov (United States)

    Landi, Giovanni; Martinetti, Pierre

    2016-11-01

    We systematically investigate ways to twist a real spectral triple via an algebra automorphism and in particular, we naturally define a twisted partner for any real graded spectral triple. Among other things, we investigate consequences of the twisting on the fluctuations of the metric and possible applications to the spectral approach to the Standard Model of particle physics.

  16. Triple Play Service and IPTV Services Offered within it

    Directory of Open Access Journals (Sweden)

    Dagmar Pajdusakova

    2008-01-01

    Full Text Available This paper deals with Triple Play multimedia service and figures its architecture. Triple Play offers voice, video and data services together in one customer connection. There is offered IPTV (Internet Protocol Television service within this service, where we can include also Video on Demand service and other different additional services. In the paper is described classification of Video on Demand services.

  17. Fibonacci-triple sequences and some fundamental properties

    OpenAIRE

    Bijendra Singh; Omprakash Sikhwal

    2010-01-01

    Fibonacci sequence stands as a kind of super sequence with fabulous properties. This note presents Fibonacci-Triple sequences that may also be called 3-F sequences. This is the explosive development in the region of Fibonacci sequence. Our purpose of this paper is to demonstrate fundamental properties of Fibonacci-Triple sequence.

  18. On Twisting Real Spectral Triples by Algebra Automorphisms

    Science.gov (United States)

    Landi, Giovanni; Martinetti, Pierre

    2016-08-01

    We systematically investigate ways to twist a real spectral triple via an algebra automorphism and in particular, we naturally define a twisted partner for any real graded spectral triple. Among other things, we investigate consequences of the twisting on the fluctuations of the metric and possible applications to the spectral approach to the Standard Model of particle physics.

  19. Theory of restriction degree of Triple I method with total inference rules of fuzzy reasoning

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Based on the theory of sustentation degree of Triple I method together with the formulas of a-Triple I modus ponens (MP) and a-Triple I modus tollens( MT), the theory of restriction degree of Triple I method is proposed. Its properties are analyzed, and the general formulas of supremum of a-Triple IMP and infimum of a-Triple I MT are obtained.

  20. Safe and Liquid Mortgage Bonds

    DEFF Research Database (Denmark)

    Dick-Nielsen, Jens; Gyntelberg, Jacob; Lund, Jesper

    This paper shows that strict match pass-through funding of covered bonds provides safe and liquid mortgage bonds. Despite a 30% drop in house prices during the 2008 global crisis Danish mortgage bonds remained as liquid as most European government bonds. The Danish pass-through system effectively...... eliminates credit risk from the investor's perspective. Similar to other safe bonds, funding liquidity becomes the main driver of mortgage bond liquidity and this creates commonality in liquidity across markets and countries. These findings have implications for how to design a robust mortgage bond system...

  1. Control of Collagen Triple Helix Stability by Phosphorylation.

    Science.gov (United States)

    Acevedo-Jake, Amanda M; Ngo, Daniel H; Hartgerink, Jeffrey D

    2017-03-10

    The phosphorylation of the collagen triple helix plays an important role in collagen synthesis, assembly, signaling, and immune response, although no reports detailing the effect this modification has on the structure and stability of the triple helix exist. Here we investigate the changes in stability and structure resulting from the phosphorylation of collagen. Additionally, the formation of pairwise interactions between phosphorylated residues and lysine is examined. In all tested cases, phosphorylation increases helix stability. When charged-pair interactions are possible, stabilization via phosphorylation can play a very large role, resulting inasmuch as a 13.0 °C increase in triple helix stability. Two-dimensional NMR and molecular modeling are used to study the local structure of the triple helix. Our results suggest a mechanism of action for phosphorylation in the regulation of collagen and also expand upon our understanding of pairwise amino acid stabilization of the collagen triple helix.

  2. Rational design of a triple helix-specific intercalating ligand.

    Science.gov (United States)

    Escudé, C; Nguyen, C H; Kukreti, S; Janin, Y; Sun, J S; Bisagni, E; Garestier, T; Hélène, C

    1998-03-31

    DNA triple helices offer new perspectives toward oligonucleotide-directed gene regulation. However, the poor stability of some of these structures might limit their use under physiological conditions. Specific ligands can intercalate into DNA triple helices and stabilize them. Molecular modeling and thermal denaturation experiments suggest that benzo[f]pyrido[3, 4-b]quinoxaline derivatives intercalate into triple helices by stacking preferentially with the Hoogsteen-paired bases. Based on this model, it was predicted that a benzo[f]quino[3,4-b]quinoxaline derivative, which possesses an additional aromatic ring, could engage additional stacking interactions with the pyrimidine strand of the Watson-Crick double helix upon binding of this pentacyclic ligand to a triplex structure. This compound was synthesized. Thermal denaturation experiments and inhibition of restriction enzyme cleavage show that this new compound can indeed stabilize triple helices with great efficiency and specificity and/or induce triple helix formation under physiological conditions.

  3. Corporate Bonds in Denmark

    DEFF Research Database (Denmark)

    Tell, Michael

    2015-01-01

    Corporate financing is the choice between capital generated by the corporation and capital from external investors. However, since the financial crisis shook the markets in 2007–2008, financing opportunities through the classical means of financing have decreased. As a result, corporations have...... markets. However, NASDAQ OMX has introduced the First North Bond Market in December 2012 and new regulatory framework came into place in 2014, which may contribute to a Danish based corporate bond market. The purpose of this article is to present the regulatory changes in Denmark in relation to corporate...

  4. The Trouble With Bonds

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ In early June,global financial markets gyrated downwards in the wake of central banks'tough language on inflation.At one point bond prices reflected expectations of four rate hikes by the US Federal Reserve (Fed) in the next 12 months.As a result,the dollar firmed,oil prices stabilized,and yield curves flattened around the world.If all these inflation-fighting measures are real,the situation bodes well for bonds.But,I think otherwise.

  5. Cooperativity in beryllium bonds.

    Science.gov (United States)

    Alkorta, Ibon; Elguero, José; Yáñez, Manuel; Mó, Otilia

    2014-03-07

    A theoretical study of the beryllium bonded clusters of the (iminomethyl)beryllium hydride and (iminomethyl)beryllium fluoride [HC(BeX)=NH, X = H, F] molecules has been carried out at the B3LYP/6-311++G(3df,2p) level of theory. Linear and cyclic clusters have been characterized up to the decamer. The geometric, energetic, electronic and NMR properties of the clusters clearly indicate positive cooperativity. The evolution of the molecular properties, as the size of the cluster increases, is similar to those reported in polymers held together by hydrogen bonds.

  6. Can synergy in Triple Helix relations be quantified? A review of the development of the Triple Helix indicator

    NARCIS (Netherlands)

    Leydesdorff, L.; Park, H.W.

    2014-01-01

    Triple Helix arrangements of bi- and trilateral relations can be considered as adaptive ecosystems. During the last decade, we have further developed a Triple Helix indicator of synergy as reduction of uncertainty in niches that can be shaped among three or more sets of relations. Reduction of uncer

  7. Hydrogen bond and halogen bond inside the carbon nanotube

    Science.gov (United States)

    Wang, Weizhou; Wang, Donglai; Zhang, Yu; Ji, Baoming; Tian, Anmin

    2011-02-01

    The hydrogen bond and halogen bond inside the open-ended single-walled carbon nanotubes have been investigated theoretically employing the newly developed density functional M06 with the suitable basis set and the natural bond orbital analysis. Comparing with the hydrogen or halogen bond in the gas phase, we find that the strength of the hydrogen or halogen bond inside the carbon nanotube will become weaker if there is a larger intramolecular electron-density transfer from the electron-rich region of the hydrogen or halogen atom donor to the antibonding orbital of the X-H or X-Hal bond involved in the formation of the hydrogen or halogen bond and will become stronger if there is a larger intermolecular electron-density transfer from the electron-rich region of the hydrogen or halogen atom acceptor to the antibonding orbital of the X-H or X-Hal bond. According to the analysis of the molecular electrostatic potential of the carbon nanotube, the driving force for the electron-density transfer is found to be the negative electric field formed in the carbon nanotube inner phase. Our results also show that the X-H bond involved in the formation of the hydrogen bond and the X-Hal bond involved in the formation of the halogen bond are all elongated when encapsulating the hydrogen bond and halogen bond within the carbon nanotube, so the carbon nanotube confinement may change the blue-shifting hydrogen bond and the blue-shifting halogen bond into the red-shifting hydrogen bond and the red-shifting halogen bond. The possibility to replace the all electron nanotube-confined calculation by the simple polarizable continuum model is also evaluated.

  8. Triple-layer smart grid business model

    DEFF Research Database (Denmark)

    Ma, Zheng; Lundgaard, Morten; Jørgensen, Bo Nørregaard

    2016-01-01

    Viewing the smart grid with the theory of business models may open opportunities in understanding and capturing values in new markets. This study tries to discover and map the smart grid ecosystem-based business model framework with two different environments (sub-Saharan Africa and Denmark......), and identifies the parameters for the smart grid solutions to the emerging markets. This study develops a triple-layer business model including the organizational (Niche), environmental (Intermediate), and global (Dominators) factors. The result uncovers an interface of market factors and stakeholders...... in a generic smart grid constellation. The findings contribute the transferability potential of the smart grid solutions between countries, and indicate the potential to export and import smart grid solutions based on the business modeling....

  9. Mathematical modelling of triple arterial stenoses.

    Science.gov (United States)

    Ang, K C; Mazumdar, J

    1995-06-01

    This paper examines the effects of triple stenoses (ie. three stenoses in series) in a reasonably large artery. The model developed is axi-symmetric and blood is assumed to be a Newtonian fluid. The governing equations are the Navier-Stokes equations and the continuity equation. These equations are solved using the Finite Element Method and the FIDAP computational fluid dynamics (C.F.D.) package. Various combinations of differing degrees of stenosis in the triplet are considered. Pressure drop profiles and streamline plots of the solutions to these models show that the effects of milder stenoses are diminished in the presence of more severe ones. Also, a pressure recovery is observed whenever a mild stenosis follows a more severe stenosis in multiply stenosed arteries.

  10. Polarized triple-axis spectrometer TASP

    Energy Technology Data Exchange (ETDEWEB)

    Boeni, P.; Keller, P. [Lab. for Neutron Scattering ETH Zurich, Zurich (Switzerland) and Paul Scherrer Institute, Villigen (Switzerland)

    1996-11-01

    The polarized triple-axis spectrometer TASP at SINQ has been optimized for measuring magnetic cross sections in condensed matter. The neutrons are polarized or analyzed either by means of benders or Heusler monochromators. The beam divergence, i.e. the intensity, and the spectral range of the neutrons is rather large because of the supermirror coatings of the feeding neutron guide. The intensity can be further increased at the sample position by means of a focussing monochromator and a focussing anti-trumpet. The end position of TASP allows the tailoring of the neutron beam already before the monochromator and to scatter neutrons over very wide ranges of angles. (author) 6 figs., 1 tab., 8 refs.

  11. The Triple Helix of the Organizational Knowledge

    Directory of Open Access Journals (Sweden)

    Contantin BRĂTIANU

    2013-09-01

    Full Text Available The purpose of this paper is to present the inner triple helix dynamics of the organizationalknowledge. This is a new perspective of the classical view of tacit knowledge– explicit knowledge dyad of the organizational knowledge promoted by Nonaka and hisco-workers. The new perspective is based on the metaphor that organizational knowledge isa "eld rather than a stock, or stocks and flows. It is a complex metaphor using the thermodynamicsprinciples. The organizational knowledge is composed of three different "elds: cognitiveknowledge, emotional knowledge and spiritual knowledge. These "elds are nonuniform,nonhomogeneous and they interact in a dynamic way. Cognitive "eld contains knowledgeabout what is, emotional "eld contains knowledge about how we feel, and the spiritual "eldcontains knowledge about people’s aspirations and life values. This new perspective opens anew opportunity in understanding the challenges for the 21st century management.

  12. [Triple therapy in chronic obstructive pulmonary disease].

    Science.gov (United States)

    Baloira, Adolfo

    2010-01-01

    Chronic obstructive pulmonary disease (COPD) is one of the most important respiratory diseases, characterized by its multicomponent complexity, with chronic inflammation, increased airway resistance and exacerbations. Several drugs are currently available for its treatment, which act on distinct targets. Bronchodilators, especially prolonged-action bronchodilators, are the most potent and there are two groups: beta-2 mimetics and anticholinergics. Inhaled corticosteroids are the main anti-inflammatory drugs but have modest efficacy and their use is reserved for patients with severe disease and frequent exacerbations and/or asthma traits. Associating these three drugs can improve symptom control, improve quality of life and reduce the number of exacerbations. The present article reviews the evidence supporting this triple combination, as well as published studies.

  13. Thermal striping in triple jet flow

    Energy Technology Data Exchange (ETDEWEB)

    Durve, A. [Department Of Chemical Engineering, Institute of Chemical Technology, Matunga, Mumbai 400019 (India); Patwardhan, A.W., E-mail: aw.patwardhan@ictmumbai.edu.i [Department Of Chemical Engineering, Institute of Chemical Technology, Matunga, Mumbai 400019 (India); Banarjee, I.; Padmakumar, G.; Vaidyanathan, G. [Experimental Thermal Hydraulics Section, Separation Technology and Hydraulics Division, Fast Reactor Technology Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102 (India)

    2010-10-15

    A quantitative analysis of temperature fluctuations is necessary for understanding the implications of thermal striping phenomenon occurring in the core outlet region of the fast breeder reactor (FBR). In the present study, the applicability of the temperature variance model and associated modeling for the triple jet flow has been evaluated. A system of three non-isothermal parallel jets, experimented by and has been used to simulate the flow occurring at the core outlet region of the FBR. The velocity fields of the flow have been predicted using the Reynolds stress model. The performance of the temperature variance model was tested using different turbulent Prandtl numbers and different algebraic models for scalar dissipation rate. The predictions were validated with the experimental results of the respective authors. The predicted values of mean temperature were found to be sensitive to turbulent Prandtl number. In this study turbulent Prandtl number was found to vary along the flow field as a function of turbulent Reynolds number.

  14. The Triple Helix Perspective of Innovation Systems

    CERN Document Server

    Leydesdorff, Loet

    2010-01-01

    Alongside the neo-institutional model of networked relations among universities, industries, and governments, the Triple Helix can be provided with a neo-evolutionary interpretation as three selection environments operating upon one another: markets, organizations, and technological opportunities. How are technological innovation systems different from national ones? The three selection environments fulfill social functions: wealth creation, organization control, and organized knowledge production. The main carriers of this system-industry, government, and academia-provide the variation both recursively and by interacting among them under the pressure of competition. Empirical case studies enable us to understand how these evolutionary mechanisms can be expected to operate in historical instance. The model is needed for distinguishing, for example, between trajectories and regimes.

  15. Acupoints Combination Characteristics of Jin's Triple Acupuncture

    Institute of Scientific and Technical Information of China (English)

    YUAN Qing; XIAO Yuan-chun

    2007-01-01

    @@ JIN Rui is a leading professor of Guangzhou University of Traditional Chinese Medicine, famous acupuncturist, the initiator of "Jin's Triple Acupuncture", supervisor of doctorial candidates, the first Director of the Department of Acupuncture of Guangzhou College of Traditional Chinese Medicine,head of Acupuncture Institute, a member of the second and third Appraisal Group of the Degree Committee of the State Council, a member of China's International Acupunctural Examination Commission,the permanent member of the second session of China's Acupuncture Society, vice-president of literature association of China's Acupuncture Society,vice-chairman of Guangdong Provincial Acupuncture Society, chairman of Guangzhou Acupuncture Association, a tutor appointed by Personnel Ministry,Public Health Ministry and State Administration of Traditional Chinese Medicine.

  16. Neutron triples counting data for uranium

    Energy Technology Data Exchange (ETDEWEB)

    Croft, Stephen, E-mail: crofts@ornl.gov [Oak Ridge National laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831 (United States); LaFleur, Adrienne M. [Los Alamos National Laboratory, Los Alamos , NM 87545 (United States); McElroy, Robert D. [Oak Ridge National laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831 (United States); Swinhoe, Martyn T. [Los Alamos National Laboratory, Los Alamos , NM 87545 (United States)

    2015-06-01

    Correlated neutron counting using multiplicity shift register logic extracts the first three factorial moments from the detected neutron pulse train. The descriptive properties of the measurement item (mass, the ratio of (α,n) to spontaneous fission neutron production, and leakage self-multiplication) are related to the observed singles (S), doubles (D) and triples (T) rates, and this is the basis of the widely used multiplicity counting assay method. The factorial moments required to interpret and invert the measurement data in the framework of the point kinetics model may be calculated from the spontaneous fission prompt neutron multiplicity distribution P(ν). In the case of {sup 238}U very few measurements of P(ν) are available and the derived values, especially for the higher factorial moments, are not known with high accuracy. In this work, we report the measurement of the triples rate per gram of {sup 238}U based on the analysis of a set of measurements in which a collection of 10 cylinders of UO{sub 2}F{sub 2}, each containing about 230 g of compound, were measured individually and in groups. Special care was taken to understand and compensate the recorded multiplicity histograms for the effect of random cosmic-ray induced background neutrons, which, because they also come in bursts and mimic fissions but with a different and harder multiplicity distribution. We compare our fully corrected (deadtime, background, efficiency, multiplication) experimental results with first principles expectations based on evaluated nuclear data. Based on our results we suspect that the current evaluated nuclear data is biased, which points to a need to undertake new basic measurements of the {sup 238}U prompt neutron multiplicity distribution.

  17. Fractura triple del complejo suspensorio del hombro

    Directory of Open Access Journals (Sweden)

    Eraclio Delgado Rifá

    2015-06-01

    Full Text Available El complejo suspensorio del hombro es una estructura sumamente importante, compuesta por un anillo de huesos y tejidos blandos. Las lesiones aisladas de este complejo anatómico son frecuentes y no afectan su estabilidad. La interrupción doble conduce a la inestabilidad de esta estructura y usualmente requiere tratamiento quirúrgico. La triple interrupción, por su parte, es sumamente rara y es encontrada en casos de trauma de alta energía a menudo en asociación con otras lesiones. Se presenta una triple lesión del complejo suspensorio del hombro en un paciente de 46 años de edad, con una fractura de la glenoides, del acromion tipo III de Kuhn y de la coracoides tipo II de Ogawa. En este caso, la fractura del acromion fue tratada con fijación percutánea con alambres de Kirschner, por tener asociado lesiones de partes blandas que contraindicaron la reducción abierta. La fractura de la glenoides y de la apófisis coracoides fueron tratadas conservadoramente. Después de 6 meses de evolución, el paciente tuvo un resultado funcional aceptable, con una abducción de 90 grados, los 30 grados de rotación externa y 70 de rotación interna, además asintomático y consolidación de todas las fracturas. A pesar de ser catalogada de una lesión grave del cinturón escapular y estar asociada a otras lesiones se obtuvo un resultado satisfactorio al final del tratamiento.

  18. Clinicopathological Features of Triple Negative Breast Carcinoma

    Science.gov (United States)

    Reddy, Gowry Maram; Pai, Radha R.

    2017-01-01

    Introduction Breast carcinoma is one of the most common malignancies affecting women in developing countries. Molecular studies of breast carcinoma have classified the tumour based on the immunohistochemical staining into 4 subtypes, such as Luminal A, Luminal B, HER2/neu Positive and Triple Negative Breast Carcinoma (TNBC). TNBCs are reported to have an aggressive behaviour and wide metastasis, leading to selective treatment outcomes. Aim The aim was to study the clinicopathological features such as age, site, tumour size, histopathological type, histologic grade, lymph node status, stage and treatment outcomes of triple negative breast carcinoma. Materials and Methods A retrospective study was conducted on 108 cases of breast carcinoma received during the period of 2 years. The tumour was classified based on immunohistochemical staining into four subtypes. The clinicopathological details, histomorphological and immunohistochemical features of TNBC were studied. Results Of the 108 patients, 34 patients were diagnosed as TNBC. The average age at presentation was 48 years. Most of the cases showed Nottingham Modification of Scarff Bloom-Richardson (NMBR) grade 3 (55.9%) and stage II (67.6%). Ly-mph node metastasis was seen in 50% of cases. Infiltrating ductal carcinoma (not otherwise specified) type (91.2%) was the most common histological type. Among the other subtypes, Luminal A carcinoma was the most common (36.1%), followed by TNBC (31.5%) and HER2/neu positive carcinomas (28.7%). Compared to the other types of tumours, TNBC showed the most frequent distant lymph node metastasis (50%) when compared to luminal A (38.5%), luminal B (25%), HER2/neu positive (48.4%). Unlike the other types of tumours, TNBC were mostly high-grade. Conclusion TNBC have an aggressive behaviour compared to other subtypes with higher NMBR grade, nuclear pleomorphism, high mitotic rate and lymph node metastasis. PMID:28273970

  19. Triple negative breast cancer: an Indian perspective

    Directory of Open Access Journals (Sweden)

    Akhtar M

    2015-08-01

    Full Text Available Murtaza Akhtar, Subhrajit Dasgupta, Murtuza Rangwala Department of Surgery, NKP Salve Institute of Medical Sciences and Research Centre, Nagpur, Maharashtra, India Introduction: Breast cancer is the most common female cancer in the world. Triple negative breast cancer (TNBC is a recently identified biological variant with aggressive tumor behavior and poor prognosis. Data of hormonal status from the Indian population is scarce due to financial constraints in performing immunohistochemistry evaluation. The present study aims to prospectively analyze receptor status of all breast cancer patients and identify TNBC and compare their clinical profile and short term survival with other non-TNBC group. Materials and methods: All cytologically and histopathologically confirmed cases of carcinoma breast were prospectively enrolled. In a longitudinal study at tertiary care hospital in central India based on the hormonal status, they were further divided into TNBC and other groups. Comparison of risk factors, clinical profile and short-term survival was carried out. Results: A total 85 patients were enrolled and of them 37 (43.7% were TNBC. On comparing risk factors ie, age, age at menarche, total reproductive age, age at first child birth, and menopausal status – no statistical significance was observed between the TNBC and non-TNBC groups. But on comparison of clinical profile TNBC tumors were significantly large with majority of patients presenting as locally advanced breast cancer (83%. No statistical difference was observed in axillary lymph node status between two groups. TNBC tumors were histologically more aggressive (grade 3 compared to other groups. No statistically significant difference was observed in short term overall survival but all three deaths were observed in the TNBC group only and two local recurrences after surgery were observed in the TNBC group. Conclusion: TNBC forms a large proportion of carcinoma breast patients in a central

  20. Comparison of Triple Therapy plus Probiotic Yogurt vs. Standard Triple Therapy on Helicobacter Pylori Eradication

    Directory of Open Access Journals (Sweden)

    Vahid Mirzaee

    2013-04-01

    Full Text Available Background: Treatment of Helicobacter pylori as a major cause of gastric diseases is of utmost concern. We aimed to assess efficacy of triple therapy (amoxicillin, clarithromycin and pantoprazole plus probiotic yogurt (PY on eradication of H. pylori. Materials and Methods: Total 102 H. pylori positive patients were divided to 3 groups equally and randomly. For treatment of each group amoxicillin, clarithromycin and pantoprazole were used. Group A had additional PY and Group B ordinary low fat yogurt in their regimen as well. These groups were compared regarding treatment success.Results: Total number of 88 patients finished the treatment course. The most common experienced side effects were dysgeusia in groups A and B (25.8% and 32.3%, respectively, and dysgeusia with diarrhea and abdominal pain (30.8% in group C. Eradication rate was, respectively, 61.3%, 64.5% and 71.3% in group A, B and C of which difference was not statistically significant. However, the difference between 3 groups in regard to education level was statistically significant (p=0.005.Conclusion: PY enriched triple therapy has decreased side effects of antibiotics consumption; however, this has no impact on eradication of H. pylori. PY and triple therapy can be used concomitantly to increase the patient tolerance.

  1. Photochemical tissue bonding

    Science.gov (United States)

    Redmond, Robert W.; Kochevar, Irene E.

    2012-01-10

    Photochemical tissue bonding methods include the application of a photosensitizer to a tissue and/or tissue graft, followed by irradiation with electromagnetic energy to produce a tissue seal. The methods are useful for tissue adhesion, such as in wound closure, tissue grafting, skin grafting, musculoskeletal tissue repair, ligament or tendon repair and corneal repair.

  2. Bonding in cementitious composites

    Energy Technology Data Exchange (ETDEWEB)

    Mindess, S. (British Columbia Univ., Vancouver, BC (Canada)) Shah, S.P. (Northwestern Univ., Evanston, IL (USA))

    1988-01-01

    These proceedings discuss the papers presented at the symposium on the subject of high performance cement composites. Some of the topics discussed were; calcium hydroxides treated ceramics microspheres and mechanical properties of high temperature light weight cements; microstructure and chemical variations of class F fly ash; microstructure and bond strength of cement and crack propagation as detected by laser holography and acoustic emission.

  3. Thermal Bond System.

    Science.gov (United States)

    1995-10-31

    a twill weave, a crowfoot weave, a satin weave (FIG. 2), and a leno weave. Descriptions of the various weave types can be found in " Composite ...together to define a fabric mesh having first and second opposing woven surfaces. An adhesive bond that is flowable prior to drying is used to wet and

  4. Triple therapy for the management of COPD: a review.

    Science.gov (United States)

    Gaebel, Kathryn; McIvor, R Andrew; Xie, Feng; Blackhouse, Gord; Robertson, Diana; Assasi, Nazila; Hernandez, Paul; Goeree, Ron

    2011-06-01

    Triple therapy for COPD consists of a long-acting anti-cholinergic bronchodilator, a long-acting beta-agonist bronchodilator, and an inhaled corticosteroid. Guidelines from the Canadian Thoracic Society advocate triple therapy for some patients with moderate-to-severe COPD. The objective of this review was to evaluate the evidence based clinical efficacy of triple therapy compared to dual bronchodilator therapy (long-acting anti-cholinergic bronchodilator + beta-agonist bronchodilator) or long-acting anti-cholinergic bronchodilator monotherapy for managing COPD. A systematic literature search was conducted to identify relevant clinical evaluations of triple therapy in the management of moderate to severe COPD. Databases searched included: Medline; EMBASE; CINAHL and PubMed (non-Medline records only). Of 2,314 publications, 4 articles evaluated triple therapy for the management of COPD. Hospitalization rates for COPD exacerbations, reported in 2 trials, were significantly reduced with triple therapy compared to long-acting anti-cholinergic bronchodilator monotherapy, with reported relative risks of 0.53 (95% CI: 0.33, 0.86, p = 0.01) and 0.35 (95% CI: 0.16-0.78, p = 0.011). Exacerbation data is inconsistent between the two trials reporting this outcome. Lung function, dyspnea and quality of life data show statistical significant changes with triple therapy compared to long-acting anti-cholinergic bronchodilator monotherapy but the changes do not reach clinical importance. Triple therapy does decrease the number of hospitalizations for severe/acute COPD exacerbations compared with long-acting anti-cholinergic bronchodilator monotherapy. There is insufficient evidence to determine if triple therapy is superior to dual bronchodilator therapy.

  5. Vectorized data acquisition and fast triple-correlation integrals for Fluorescence Triple Correlation Spectroscopy

    Science.gov (United States)

    Ridgeway, William K.; Millar, David P.; Williamson, James R.

    2013-04-01

    Fluorescence Correlation Spectroscopy (FCS) is widely used to quantify reaction rates and concentrations of molecules in vitro and in vivo. We recently reported Fluorescence Triple Correlation Spectroscopy (F3CS), which correlates three signals together instead of two. F3CS can analyze the stoichiometries of complex mixtures and detect irreversible processes by identifying time-reversal asymmetries. Here we report the computational developments that were required for the realization of F3CS and present the results as the Triple Correlation Toolbox suite of programs. Triple Correlation Toolbox is a complete data analysis pipeline capable of acquiring, correlating and fitting large data sets. Each segment of the pipeline handles error estimates for accurate error-weighted global fitting. Data acquisition was accelerated with a combination of off-the-shelf counter-timer chips and vectorized operations on 128-bit registers. This allows desktop computers with inexpensive data acquisition cards to acquire hours of multiple-channel data with sub-microsecond time resolution. Off-line correlation integrals were implemented as a two delay time multiple-tau scheme that scales efficiently with multiple processors and provides an unprecedented view of linked dynamics. Global fitting routines are provided to fit FCS and F3CS data to models containing up to ten species. Triple Correlation Toolbox is a complete package that enables F3CS to be performed on existing microscopes. Catalogue identifier: AEOP_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEOP_v1_0.html Program obtainable from: CPC Program Library, Queen’s University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 50189 No. of bytes in distributed program, including test data, etc.: 6135283 Distribution format: tar.gz Programming language: C/Assembly. Computer: Any with GCC and

  6. Trading in Treasury Bond Futures Contracts and Bonds in Australia

    OpenAIRE

    Belinda Cheung

    2014-01-01

    Treasury bond futures are a key financial product in Australia, with turnover in Treasury bond futures contracts significantly larger than turnover in the market for Commonwealth Government securities (CGS). Treasury bond futures contracts provide a wide variety of market participants with the ability to hedge against, or gain exposure to, interest rate risk. This article discusses some of the features of the Treasury bond futures contract, and how the contract is used to facilitate hedging a...

  7. Fast and accurate predictions of covalent bonds in chemical space

    Science.gov (United States)

    Chang, K. Y. Samuel; Fias, Stijn; Ramakrishnan, Raghunathan; von Lilienfeld, O. Anatole

    2016-05-01

    We assess the predictive accuracy of perturbation theory based estimates of changes in covalent bonding due to linear alchemical interpolations among molecules. We have investigated σ bonding to hydrogen, as well as σ and π bonding between main-group elements, occurring in small sets of iso-valence-electronic molecules with elements drawn from second to fourth rows in the p-block of the periodic table. Numerical evidence suggests that first order Taylor expansions of covalent bonding potentials can achieve high accuracy if (i) the alchemical interpolation is vertical (fixed geometry), (ii) it involves elements from the third and fourth rows of the periodic table, and (iii) an optimal reference geometry is used. This leads to near linear changes in the bonding potential, resulting in analytical predictions with chemical accuracy (˜1 kcal/mol). Second order estimates deteriorate the prediction. If initial and final molecules differ not only in composition but also in geometry, all estimates become substantially worse, with second order being slightly more accurate than first order. The independent particle approximation based second order perturbation theory performs poorly when compared to the coupled perturbed or finite difference approach. Taylor series expansions up to fourth order of the potential energy curve of highly symmetric systems indicate a finite radius of convergence, as illustrated for the alchemical stretching of H 2+ . Results are presented for (i) covalent bonds to hydrogen in 12 molecules with 8 valence electrons (CH4, NH3, H2O, HF, SiH4, PH3, H2S, HCl, GeH4, AsH3, H2Se, HBr); (ii) main-group single bonds in 9 molecules with 14 valence electrons (CH3F, CH3Cl, CH3Br, SiH3F, SiH3Cl, SiH3Br, GeH3F, GeH3Cl, GeH3Br); (iii) main-group double bonds in 9 molecules with 12 valence electrons (CH2O, CH2S, CH2Se, SiH2O, SiH2S, SiH2Se, GeH2O, GeH2S, GeH2Se); (iv) main-group triple bonds in 9 molecules with 10 valence electrons (HCN, HCP, HCAs, HSiN, HSi

  8. On Pythagoras Theorem for Products of Spectral Triples

    Science.gov (United States)

    D'Andrea, Francesco; Martinetti, Pierre

    2013-05-01

    We discuss a version of Pythagoras theorem in noncommutative geometry. Usual Pythagoras theorem can be formulated in terms of Connes' distance, between pure states, in the product of commutative spectral triples. We investigate the generalization to both non-pure states and arbitrary spectral triples. We show that Pythagoras theorem is replaced by some Pythagoras inequalities, that we prove for the product of arbitrary (i.e. non-necessarily commutative) spectral triples, assuming only some unitality condition. We show that these inequalities are optimal, and we provide non-unital counter-examples inspired by K-homology.

  9. On Integrable Roots in Split Lie Triple Systems

    Institute of Scientific and Technical Information of China (English)

    A.J.CALDER(O)N MART(I)N

    2009-01-01

    We focus on the notion of an integrable root in the framework of split Lie triple systems T with a coherent 0-root space. As a main result, it is shown that if T has all its nonzero roots integrable, then its standard embedding is a split Lie algebra having all its nonzero roots integrable. As a consequence, a local finiteness theorem for split Lie triple systems, saying that whenever all nonzero roots of T are integrable then T is locally finite, is stated. Finally, a classification theorem for split simple Lie triple systems having all its nonzero roots integrable is given.

  10. Superconformal M2-branes and generalized Jordan triple systems

    CERN Document Server

    Nilsson, Bengt E W

    2008-01-01

    Three-dimensional conformal theories with six supersymmetries and SU(4) R-symmetry describing stacks of M2-branes are here proposed to be related to generalized Jordan triple systems. Writing the four-index structure constants in an appropriate form, the Chern-Simons part of the action immediately suggests a connection to such triple systems. In this note we show that the whole theory with six manifest supersymmetries can be naturally expressed in terms of structure constants of generalized Jordan triple systems. We comment on the associated graded Lie algebra, which corresponds to an extension of the gauge group.

  11. Examples of infinite direct sums of spectral triples

    Science.gov (United States)

    Falk, Kevin

    2017-02-01

    We study two ways of summing an infinite family of noncommutative spectral triples. First, we propose a definition of the integration of spectral triples and give an example using algebras of Toeplitz operators acting on weighted Bergman spaces over the unit ball of Cn. Secondly, we construct a spectral triple associated to a general polygonal self-similar set in C using algebras of Toeplitz operators on Hardy spaces. In this case, we show that we can recover the Hausdorff dimension of the fractal set.

  12. Ternary Weakly Amenable C*-algebras and JB*-triples

    CERN Document Server

    Ho, Tony; Russo, Bernard

    2012-01-01

    A well known result of Haagerup from 1983 states that every C*-algebra A is weakly amenable, that is, every (associative) derivation from A into its dual is inner. A Banach algebra B is said to be ternary weakly amenable if every continuous Jordan triple derivation from B into its dual is inner. We show that commutative C*-algebras are ternary weakly amenable, but that B(H) and K(H) are not, unless H is finite dimensional. More generally, we inaugurate the study of weak amenability for Jordan Banach triples, focussing on commutative JB*-triples and some Cartan factors.

  13. Extended superconformal symmetry, Freudenthal triple systems and gauged WZW models

    CERN Document Server

    Günaydin, M

    1995-01-01

    We review the construction of extended ( N=2 and N=4 ) superconformal algebras over triple systems and the gauged WZW models invariant under them. The N=2 superconformal algebras (SCA) realized over Freudenthal triple systems (FTS) admit extension to ``maximal'' N=4 SCA's with SU(2)XSU(2)XU(1) symmetry. A detailed study of the construction and classification of N=2 and N=4 SCA's over Freudenthal triple systems is given. We conclude with a study and classification of gauged WZW models with N=4 superconformal symmetry.

  14. Indirect bonding technique in orthodontics

    Directory of Open Access Journals (Sweden)

    Kübra Yıldırım

    2016-08-01

    Full Text Available ‘Direct Bonding Technique’ which allows the fixed orthodontic appliances to be directly bonded to teeth without using bands decreased the clinic time for bracket bonding and increased esthetics and oral hygiene during orthodontic treatment. However, mistakes in bracket positioning were observed due to decreased direct visual sight and access to posterior teeth. ‘Indirect Bonding Technique’ was developed for eliminating these problems. Initially, decreased bond strength, higher bond failure rate, periodontal tissue irritation, compromised oral hygiene and increased laboratory time were the main disadvantages of this technique when compared to direct bonding. The newly developed materials and modified techniques help to eliminate these negative consequences. Today, the brackets bonded with indirect technique have similar bond strength with brackets bonded directly. Moreover, indirect and direct bonding techniques have similar effects on periodontal tissues. However, indirect bonding technique requires more attention and precision in laboratory and clinical stage, and has higher cost. Orthodontist's preference between these two bonding techniques may differ according to time spent in laboratory and clinic, cost, patient comfort and personal opinion.

  15. Arctigenin inhibits STAT3 and exhibits anticancer potential in human triple-negative breast cancer therapy.

    Science.gov (United States)

    Feng, Tingting; Cao, Wei; Shen, Wanxiang; Zhang, Liang; Gu, Xinsheng; Guo, Yang; Tsai, Hsiang-I; Liu, Xuewen; Li, Jian; Zhang, Jingxuan; Li, Shan; Wu, Fuyun; Liu, Ying

    2017-01-03

    Triple-negative breast cancers (TNBCs) are the most aggressive and hard-to-treat breast tumors with poor prognosis, and exploration for novel therapeutic drugs is impending. Arctigenin (Atn), a bioactive lignan isolated from seeds of Arctium lappa L, has been reported to inhibit many cancer types; however, the effect of Atn on TNBC remains unclear. In this study, we demonstrated that Atn decreased proliferation, and induced apoptosis in TNBC cells. Furthermore, we explored the underlying mechanism of Atn inhibition on TNBC cells. Computational docking and affinity assay showed that Atn bound to the SH2 domain of STAT3. Atn inhibited STAT3 binding to genomic DNA by disrupting hydrogen bond linking between DNA and STAT3. In addition, Atn augmented Taxotere®-induced TNBC cell cytotoxicity. TNBC xenograft tests also confirmed the antitumor effect of Atn in vivo. These characteristics render Atn as a promising candidate drug for further development and for designing new effective STAT3 inhibitors.

  16. China-Russia Bond

    Institute of Scientific and Technical Information of China (English)

    Ji Zhiye; Ma Zongshi

    2007-01-01

    @@ Thanks to China's successful launching of the Year of Russia, 2006 will surely go down as a milestone in the history of the China-Russia bond. Furthermore, a still-warmer climate will continue to prevail in 2007 when Moscow, in its turn, hosts the Year of China, trying to outshine its next-door neighbor in this regard, as Russian President Vladimir Putin promised in the exchange of new year greetings with his Chinese counterpart, President Hu Jintao.

  17. A Study of Neoadjuvant Paclitaxel in Combination With Bavituximab in Early- Stage Triple- Negative Breast Cancer

    Science.gov (United States)

    2017-03-08

    Breast Cancer; Triple Negative Breast Neoplasms; Triple-Negative Breast Neoplasm; Triple-Negative Breast Cancer; Triple Negative Breast Cancer; ER-Negative PR-Negative HER2-Negative Breast Neoplasms; ER-Negative PR-Negative HER2-Negative Breast Cancer

  18. Direct bonded space maintainers.

    Science.gov (United States)

    Santos, V L; Almeida, M A; Mello, H S; Keith, O

    1993-01-01

    The aim of this study was to evaluate clinically a bonded space maintainer, which would reduce chair-side time and cost. Sixty appliances were fabricated from 0.7 mm stainless steel round wire and bonded using light-cured composite to the two teeth adjacent to the site of extraction of a posterior primary tooth. Twenty males and sixteen females (age range 5-9-years-old) were selected from the Pedodontic clinic of the State University of Rio de Janeiro. The sixty space maintainers were divided into two groups according to the site in which they were placed: a) absent first primary molar and b) absent second primary molar. Impressions and study models were obtained prior to and 6 months after bonding the appliances. During this period only 8.3% of failures were observed, most of them from occlusal or facial trauma. Student t-test did not show statistically significant alterations in the sizes of the maintained spaces during the trial period.

  19. Multi-hierarchical self-assembly of a collagen mimetic peptide from triple helix to nanofibre and hydrogel.

    Science.gov (United States)

    O'Leary, Lesley E R; Fallas, Jorge A; Bakota, Erica L; Kang, Marci K; Hartgerink, Jeffrey D

    2011-08-28

    Replicating the multi-hierarchical self-assembly of collagen has long-attracted scientists, from both the perspective of the fundamental science of supramolecular chemistry and that of potential biomedical applications in tissue engineering. Many approaches to drive the self-assembly of synthetic systems through the same steps as those of natural collagen (peptide chain to triple helix to nanofibres and, finally, to a hydrogel) are partially successful, but none simultaneously demonstrate all the levels of structural assembly. Here we describe a peptide that replicates the self-assembly of collagen through each of these steps. The peptide features collagen's characteristic proline-hydroxyproline-glycine repeating unit, complemented by designed salt-bridged hydrogen bonds between lysine and aspartate to stabilize the triple helix in a sticky-ended assembly. This assembly is propagated into nanofibres with characteristic triple helical packing and lengths with a lower bound of several hundred nanometres. These nanofibres form a hydrogel that is degraded by collagenase at a similar rate to that of natural collagen.

  20. Multi-hierarchical self-assembly of a collagen mimetic peptide from triple helix to nanofibre and hydrogel

    Science.gov (United States)

    O'Leary, Lesley E. R.; Fallas, Jorge A.; Bakota, Erica L.; Kang, Marci K.; Hartgerink, Jeffrey D.

    2011-10-01

    Replicating the multi-hierarchical self-assembly of collagen has long-attracted scientists, from both the perspective of the fundamental science of supramolecular chemistry and that of potential biomedical applications in tissue engineering. Many approaches to drive the self-assembly of synthetic systems through the same steps as those of natural collagen (peptide chain to triple helix to nanofibres and, finally, to a hydrogel) are partially successful, but none simultaneously demonstrate all the levels of structural assembly. Here we describe a peptide that replicates the self-assembly of collagen through each of these steps. The peptide features collagen's characteristic proline-hydroxyproline-glycine repeating unit, complemented by designed salt-bridged hydrogen bonds between lysine and aspartate to stabilize the triple helix in a sticky-ended assembly. This assembly is propagated into nanofibres with characteristic triple helical packing and lengths with a lower bound of several hundred nanometres. These nanofibres form a hydrogel that is degraded by collagenase at a similar rate to that of natural collagen.

  1. Optimal Investment in Structured Bonds

    DEFF Research Database (Denmark)

    Jessen, Pernille; Jørgensen, Peter Løchte

    The paper examines the role of structured bonds in the optimal portfolio of a small retail investor. We consider the typical structured bond essentially repacking an exotic option and a zero coupon bond, i.e. an investment with portfolio insurance. The optimal portfolio is found when the investment...

  2. Coulombic Models in Chemical Bonding.

    Science.gov (United States)

    Sacks, Lawrence J.

    1986-01-01

    Compares the coulumbic point charge model for hydrogen chloride with the valence bond model. It is not possible to assign either a nonpolar or ionic canonical form of the valence bond model, while the covalent-ionic bond distribution does conform to the point charge model. (JM)

  3. Triple Isotope Water Analyzer for Extraplanetary Studies Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In this Small Business Innovative Research (SBIR) effort, Los Gatos Research (LGR) proposes to develop a miniature, high-resolution, low power, triple-isotope water...

  4. The universal enveloping TRO of a JB*-triple system

    CERN Document Server

    Bohle, Dennis

    2010-01-01

    We associate to every JB*-triple system a so-called universal enveloping TRO and show some functorial properties of this correspondence. We compute the universal enveloping TROs of the finite dimensional Cartan factors.

  5. Structural alignment of RNA with triple helix structure.

    Science.gov (United States)

    Wong, Thomas K F; Yiu, S M

    2012-04-01

    Structural alignment is useful in identifying members of ncRNAs. Existing tools are all based on the secondary structures of the molecules. There is evidence showing that tertiary interactions (the interaction between a single-stranded nucleotide and a base-pair) in triple helix structures are critical in some functions of ncRNAs. In this article, we address the problem of structural alignment of RNAs with the triple helix. We provide a formal definition to capture a simplified model of a triple helix structure, then develop an algorithm of O(mn(3)) time to align a query sequence (of length m) with known triple helix structure with a target sequence (of length n) with an unknown structure. The resulting algorithm is shown to be useful in identifying ncRNA members in a simulated genome.

  6. The QCD triple Pomeron coupling from string amplitudes

    CERN Document Server

    Bialas, A; Peschanski, R

    1998-01-01

    Using the recent solution of the triple Pomeron coupling in the QCD dipole picture as a closed string amplitude with six legs, its analytical form in terms of hypergeometric functions and numerical value are derived.

  7. The spectrum for overlarge sets of directed triple systems

    Institute of Scientific and Technical Information of China (English)

    Zi-hong; TIAN; Li-jun; Ji

    2007-01-01

    A directed triple system of order v, denoted by DTS(v, λ), is a pair (X,B) where X is a v-set and B is a collection of transitive triples on X such that every ordered pair of X belongs to λ triples of B. An overlarge set of disjoint DTS(v, λ), denoted by OLDTS(v, λ), is a collection {(Y\\{y}, Ai)}i,such that Y is a (v + 1)-set, each (Y\\{y}, Ai) is a DTS(v, λ) and all Ai's form a partition of all transitive triples of Y. In this paper, we shall discuss the existence problem of OLDTS(v, λ) and give the following conclusion: there exists an OLDTS(v, λ) if and only if either λ = 1 and v = 0, 1 (mod 3), or λ = 3 and v≠2.

  8. Triple Isotope Water Analyzer for Extraplanetary Studies Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Los Gatos Research (LGR) proposes to employ Off-Axis ICOS to develop triple-isotope water analyzers for lunar and other extraplanetary exploration. This instrument...

  9. The chemical bond in inorganic chemistry the bond valence model

    CERN Document Server

    Brown, I David

    2016-01-01

    The bond valence model is a version of the ionic model in which the chemical constraints are expressed in terms of localized chemical bonds formed by the valence charge of the atoms. Theorems derived from the properties of the electrostatic flux predict the rules obeyed by both ionic and covalent bonds. They make quantitative predictions of coordination number, crystal structure, bond lengths and bond angles. Bond stability depends on the matching of the bonding strengths of the atoms, while the conflicting requirements of chemistry and space lead to the structural instabilities responsible for the unusual physical properties displayed by some materials. The model has applications in many fields ranging from mineralogy to molecular biology.

  10. The Triple Helix of University-Industry-Government Relations

    OpenAIRE

    Leydesdorff, Loet

    2012-01-01

    Etzkowitz & Leydesdorff (2000) further elaborated the Triple Helix of University-Industry-Government Relations (cf. Etzkowitz & Leydesdorff, 1995; Lowe, 1982) into a model for studying knowledge-based economies. A series of workshops, conferences, and special issues of journals have developed under this title since 1996. In various countries, the Triple Helix concept has also been used as an operational strategy for regional development and to further the knowledge-based economy. This short r...

  11. TEDI: the TripleSpec Exoplanet Discovery Instrument

    CERN Document Server

    Edelstein, Jerry; Erskine, David J; Feuerstein, W Michael; Marckwordt, Mario; Wishnow, Ed; Lloyd, James P; Herter, Terry; Muirhead, Phillip; Gull, George E; Henderson, Charles; Parshley, Stephen C

    2007-01-01

    The TEDI (TripleSpec - Exoplanet Discovery Instrument) will be the first instrument fielded specifically for finding low-mass stellar companions. The instrument is a near infra-red interferometric spectrometer used as a radial velocimeter. TEDI joins Externally Dispersed Interferometery (EDI) with an efficient, medium-resolution, near IR (0.9 - 2.4 micron) echelle spectrometer, TripleSpec, at the Palomar 200" telescope. We describe the instrument and its radial velocimetry demonstration program to observe cool stars.

  12. Rehabilitation of a triple amputee including a hip disarticulation.

    Science.gov (United States)

    Shin, J C; Park, C I; Kim, Y C; Jang, S H; Bang, I K; Shin, J S

    1998-12-01

    A multiple amputee more severe than a triple amputee is uncommon. There have been no reports on the rehabilitation outcome of a triple amputee, including hip disarticulation and transtibial amputation. The authors report the rehabilitation of a patient with left hip disarticulation, right trans-tibial amputation, and left trans-humeral amputation due to a train accident. He has successfully completed the rehabilitation programme and has become independent in prosthetic ambulation, activities of daily living, and driving.

  13. Triple jump examinations for dental student assessment.

    Science.gov (United States)

    Navazesh, Mahvash; Rich, Sandra K; Chopiuk, Nasrin Bahari; Keim, Robert G

    2013-10-01

    The triple jump examination (TJE) attempts to assess a higher level of learning with demand for analysis, critical thinking, and resolution of problems presented by written scenarios based on patient care situations. The purpose of this study was to examine the internal consistency, scale reliability, and interrater reliability of the TJE used at the Ostrow School of Dentistry, University of Southern California. On the sample of 2,227 examinations administered by seventy-seven raters across a three-year time period, the Cronbach's coefficient alpha for internal consistency of the overall TJE was found to be good (a=0.869). The internal consistency of the three subscales was found to be acceptable (a=0.731), good (a=0.820), and good (a=0.820). Average and single measures intraclass correlation coefficients (ICC) for scale reliability were significant at p<0.001, indicating strong interrater reliability. There were no statistically significant differences (p≤0.05) in the mean scores assigned on the TJE between rater groups defined by rater experience level with the TJE. A very high level of agreement among rater pairs was also observed. Across the entire three-year study period, with over 19,152 ratings, the seventy-seven raters were in general agreement 99.5 percent of the time and in exact agreement 77.2 percent of the time.

  14. Applications of tripled chaotic maps in cryptography

    Energy Technology Data Exchange (ETDEWEB)

    Behnia, S. [Department of Physics, IAU, Urmia (Iran, Islamic Republic of)], E-mail: s.behnia@iaurmia.ac.ir; Akhshani, A. [School of Physics, Universiti Sains Malaysia, 11800 USM, Penang (Malaysia); Akhavan, A. [School of Computer Science, Universiti Sains Malaysia, 11800 USM, Penang (Malaysia); Mahmodi, H. [School of Physics, Universiti Sains Malaysia, 11800 USM, Penang (Malaysia)

    2009-04-15

    Security of information has become a major issue during the last decades. New algorithms based on chaotic maps were suggested for protection of different types of multimedia data, especially digital images and videos in this period. However, many of them fundamentally were flawed by a lack of robustness and security. For getting higher security and higher complexity, in the current paper, we introduce a new kind of symmetric key block cipher algorithm that is based on tripled chaotic maps. In this algorithm, the utilization of two coupling parameters, as well as the increased complexity of the cryptosystem, make a contribution to the development of cryptosystem with higher security. In order to increase the security of the proposed algorithm, the size of key space and the computational complexity of the coupling parameters should be increased as well. Both the theoretical and experimental results state that the proposed algorithm has many capabilities such as acceptable speed and complexity in the algorithm due to the existence of two coupling parameters and high security. Note that the ciphertext has a flat distribution and has the same size as the plaintext. Therefore, it is suitable for practical use in secure communications.

  15. Brown Dwarf Binaries from Disintegrating Triple Systems

    CERN Document Server

    Reipurth, Bo

    2015-01-01

    We have carried out 200,000 N-body simulations of three identical stellar embryos with masses from a Chabrier IMF and embedded in a molecular core. The bodies are initially non-hierarchical and undergo chaotic motions, while accreting using Bondi-Hoyle accretion. The coupling of dynamics and accretion often leads to one or two dominant bodies controlling the center of the cloud core, while banishing the other(s) to the lower-density outskirts, leading to stunted growth. Eventually each system transforms either to a bound hierarchical configuration or breaks apart into separate single and binary components. The orbital motion is followed for 100 Myr. To illustrate the simulations we introduce the 'triple diagnostic diagram', which plots two dimensionless numbers against each other, representing the binary mass ratio and the mass ratio of the third body to the total system mass. Numerous freefloating BD binaries are formed in these simulations. The separation distribution function is in good correspondence with...

  16. Spectroscopically resolving the Algol triple system

    CERN Document Server

    Kolbas, V; Southworth, J; Lee, C -U; Lee, D -J; Lee, J W; Kim, S -L; Kim, H -I; Smalley, B; Tkachenko, A

    2015-01-01

    Algol ($\\beta$ Persei) is the prototypical semi-detached eclipsing binary and a hierarchical triple system. From 2006 to 2010 we obtained 121 high-resolution and high-S/N \\'{e}chelle spectra of this object. Spectral disentangling yields the individual spectra of all three stars, and greatly improved elements both the inner and outer orbits. We find masses of $M_{\\rm A} = 3.39\\pm0.06$ M$_\\odot$, $M_{\\rm B} = 0.770\\pm0.009$ M$_\\odot$ and $M_{\\rm C} = 1.58\\pm0.09$ M$_\\odot$. The disentangled spectra also give the light ratios between the components in the $B$ and $V$ bands. Atmospheric parameters for the three stars are determined, including detailed elemental abundances for Algol A and Algol C. We find the following effective temperatures: $T_{\\rm A} = 12\\,550\\pm120$ K, $T_{\\rm B} = 4900\\pm300$ K and $T_{\\rm C} = 7550\\pm250$ K. The projected rotational velocities are $v_{\\rm A} \\sin i_{\\rm A} = 50.8\\pm0.8$ km/s, $v_{\\rm B} \\sin i_{\\rm B} = 62\\pm2$ km/s and $v_{\\rm C} \\sin i_{\\rm C} = 12.4\\pm0.6$ km/s. This is t...

  17. Kondo effects in triangular triple quantum dots

    Science.gov (United States)

    Oguri, Akira; Numata, Takahide; Nisikawa, Yunori; Hewson, A. C.

    2009-03-01

    We study the conductance through a triangular triple quantum dot, which is connected to two noninteracting leads, using the numerical renormalization group (NRG). It is found that the system shows a variety of Kondo effects depending on the filling of the triangle. The SU(4) Kondo effect occurs at half-filling, and a sharp conductance dip due to a phase lapse appears in the gate-voltage dependence. Furthermore, when four electrons occupy the three sites on average, a local S=1 moment, which is caused by the Nagaoka mechanism, is induced along the triangle. The temperature dependence of the entropy and spin susceptibility of the triangle shows that this moment is screened by the conduction electrons via two separate stages at different temperatures. The two-terminal and four-terminal conductances show a clear difference at the gate voltages, where the SU(4) or the S=1 Kondo effects occur[1]. We will also discuss effects of deformations of the triangular configuration, caused by the inhomogeneity in the inter-dot couplings and in the gate voltages. [4pt] [1] T.Numata, Y.Nisikawa, A.Oguri, and A.C.Hewson: arXiv:0808.3496.

  18. Triple Hybrid Energy Harvesting Interface Electronics

    Science.gov (United States)

    Uluşan, H.; Chamanian, S.; Pathirana, W. M. P. R.; Zorlu, Ö.; Muhtaroğlu, A.; Külah, H.

    2016-11-01

    This study presents a novel triple hybrid system that combines simultaneously generated power from thermoelectric (TE), vibration-based electromagnetic (EM) and piezoelectric (PZT) harvesters for a relatively high power supply capability. In the proposed solution each harvesting source utilizes a distinct power management circuit that generates a DC voltage suitable for combining the three parallel supplies. The circuits are designed and implemented in 180 nm standard CMOS technology, and are terminated with a schottky diode to avoid reverse current flow. The harvested AC signal from the EM harvester is rectified with a self-powered AC-DC doubler, which utilizes active diode structures to minimize the forward- bias voltage drop. The PZT interface electronics utilizes a negative voltage converter as the first stage, followed by synchronous power extraction and DC-to-DC conversion through internal switches, and an external inductor. The ultra-low voltage DC power harvested by the TE generator is stepped up through a charge-pump driven by an LC oscillator with fully- integrated center-tapped differential inductors. Test results indicate that hybrid energy harvesting circuit provides more than 1 V output for load resistances higher than 100 kΩ (10 μW) where the stand-alone harvesting circuits are not able to reach 1 V output. This is the first hybrid harvester circuit that simultaneously extracts energy from three independent sources, and delivers a single DC output.

  19. KIC 2856960: the impossible triple star

    CERN Document Server

    Marsh, T R; Carter, P J

    2014-01-01

    KIC 2856960 is a star in the Kepler field which was observed by Kepler for 4 years. It shows the primary and secondary eclipses of a close binary of 0.258d as well as complex dipping events that last for about 1.5d at a time and recur on a 204d period. The dips are thought to result when the close binary passes across the face of a third star. In this paper we present an attempt to model the dips. Despite the apparent simplicity of the system and strenuous efforts to find a solution, we find that we cannot match the dips with a triple star while satisfying Kepler's laws. The problem is that to match the dips the separation of the close binary has to be larger than possible relative to the outer orbit given the orbital periods. Quadruple star models can get round this problem but require the addition of a so-far undetected intermediate period of order 5 -- 20d that has be a near-perfect integer divisor of the outer 204d period. Although we have no good explanation for KIC 2856960, using the full set of Kepler ...

  20. Critical Curves and Caustics of Triple-lens Models

    CERN Document Server

    Danek, Kamil

    2015-01-01

    Among the 25 planetary systems detected up to now by gravitational microlensing, there are two cases of a star with two planets, and two cases of a binary star with a planet. Other, yet undetected types of triple lenses include triple stars or stars with a planet with a moon. The analysis and interpretation of such events is hindered by the lack of understanding of essential characteristics of triple lenses, such as their critical curves and caustics. We present here analytical and numerical methods for mapping the critical-curve topology and caustic cusp number in the parameter space of $n$-point-mass lenses. We apply the methods to the analysis of four symmetric triple-lens models, and obtain altogether 9 different critical-curve topologies and 32 caustic structures. While these results include various generic types, they represent just a subset of all possible triple-lens critical curves and caustics. Using the analyzed models, we demonstrate interesting features of triple lenses that do not occur in two-p...

  1. A directional nucleation-zipping mechanism for triple helix formation.

    Science.gov (United States)

    Alberti, Patrizia; Arimondo, Paola B; Mergny, Jean-Louis; Garestier, Thérèse; Hélène, Claude; Sun, Jian-Sheng

    2002-12-15

    A detailed kinetic study of triple helix formation was performed by surface plasmon resonance. Three systems were investigated involving 15mer pyrimidine oligonucleotides as third strands. Rate constants and activation energies were validated by comparison with thermodynamic values calculated from UV-melting analysis. Replacement of a T.A base pair by a C.G pair at either the 5' or the 3' end of the target sequence allowed us to assess mismatch effects and to delineate the mechanism of triple helix formation. Our data show that the association rate constant is governed by the sequence of base triplets on the 5' side of the triplex (referred to as the 5' side of the target oligopurine strand) and provides evidence that the reaction pathway for triple helix formation in the pyrimidine motif proceeds from the 5' end to the 3' end of the triplex according to the nucleation-zipping model. It seems that this is a general feature for all triple helices formation, probably due to the right-handedness of the DNA double helix that provides a stronger base stacking at the 5' than at the 3' duplex-triplex junction. Understanding the mechanism of triple helix formation is not only of fundamental interest, but may also help in designing better triple helix-forming oligonucleotides for gene targeting and control of gene expression.

  2. Transformation rules for decomposing heterogeneous data into triples

    Directory of Open Access Journals (Sweden)

    Mrityunjay Singh

    2015-04-01

    Full Text Available In order to fulfill the vision of a dataspace system, it requires a flexible, powerful and versatile data model that is able to represent a highly heterogeneous mix of data such as databases, web pages, XML, deep web, and files. In literature, the triple model was found a suitable candidate for a dataspace system, and able to represent structured, semi-structured and unstructured data into a single model. A triple model is based on the decomposition theory, and represents variety of data into a collection of triples. In this paper, we have proposed a decomposition algorithm for expressing various heterogeneous data models into the triple model. This algorithm is based on the decomposition theory of the triple model. By applying the decomposition algorithm, we have proposed a set of transformation rules for the existing data models. The transformation rules have been categorized for structured, semi-structured, and unstructured data models. These rules are able to decompose most of the existing data models into the triple model. We have empirically verified the algorithm as well as the transformation rules on different data sets having different data models.

  3. Additional disulfide bonds in insulin

    DEFF Research Database (Denmark)

    Vinther, Tine N; Pettersson, Ingrid; Huus, Kasper

    2015-01-01

    -chain is flexible and can adapt multiple conformations. We examined how well disulfide bond predictions algorithms could identify disulfide bonds in this region of insulin. In order to identify stable insulin analogues with additional disulfide bonds, which could be expressed, the Cβ cut-off distance had...... in comparison to analogues with additional disulfide bonds that were more difficult to predict. In contrast, addition of the fourth disulfide bond rendered all analogues resistant to fibrillation under stress conditions and all stable analogues bound to the insulin receptor with picomolar affinities. Thus...

  4. Bond strength of direct and indirect bonded brackets after thermocycling.

    Science.gov (United States)

    Daub, Jacob; Berzins, David W; Linn, Brandon James; Bradley, Thomas Gerard

    2006-03-01

    Thermocycling simulates the temperature dynamics in the oral environment. With direct bonding, thermocycling reduces the bond strength of orthodontic adhesives to tooth structure. The purpose of this study was to evaluate the shear bond strengths (SBS) of one direct and two indirect bonding methods/adhesives after thermocycling. Sixty human premolars were divided into three groups. Teeth in group 1 were bonded directly with Transbond XT. Teeth in group 2 were indirect bonded with Transbond XT/Sondhi Rapid Set, which is chemically cured. Teeth in group 3 were indirect bonded with Enlight LV/Orthosolo and light cured. Each sample was thermocycled between 5 degrees C and 55 degrees C for 500 cycles. Mean SBS in groups 1, 2, and 3 were not statistically significantly different (13.6 +/- 2.9, 12.3 +/- 3.0, and 11.6 +/- 3.2 MPa, respectively; P > .05). However, when these values were compared with the results of a previous study using the same protocol, but without thermocycling, the SBS was reduced significantly (P = .001). Weibull analysis further showed that group 3 had the lowest bonding survival rate at the minimum clinically acceptable bond-strength range. The Adhesive Remnant Index was also determined, and group 2 had a significantly (P bond failures at the resin/enamel interface.

  5. How stable is a collagen triple helix? An ab initio study on various collagen and beta-sheet forming sequences.

    Science.gov (United States)

    Pálfi, Villo K; Perczel, András

    2008-07-15

    Collagen forms the well characterized triple helical secondary structure, stabilized by interchain H-bonds. Here we have investigated the stability of fully optimized collagen triple helices and beta-pleated sheets by using first principles (ab initio and DFT) calculations so as to determine the secondary structure preference depending on the amino acid composition. Models composed of a total of 18 amino acid residues were studied at six different amino acid compositions: (i) L-alanine only, (ii) glycine only, (iii) L-alanines and glycine, (iv) L-alanines and D-alanine, (v) L-prolines with glycine, (vi) L-proline, L-hydroxyproline, and glycine. The last two, v and vi, were designed to mimic the core part of collagen. Furthermore, ii, iii, and iv model the binding and/or recognition sites of collagen. Finally, i models the G-->A replacement, rare in collagen. All calculated structures show great resemblance to those determined by X-ray crystallography. Calculated triple helix formation affinities correlate well with experimentally determined stabilities derived from melting point (T(m)) data of different collagen models. The stabilization energy of a collagen triple helical structure over that of a beta-pleated sheet is 2.1 kcal mol(-1) per triplet for the [(-Pro-Hyp-Gly-)(2)](3) collagen peptide. This changes to 4.8 kcal mol(-1) per triplet of destabilization energy for the [(-Ala-Ala-Gly-)(2)](3) sequence, known to be disfavored in collagen. The present study proves that by using first principles methods for calculating stabilities of supramolecular complexes, such as collagen and beta-pleated sheets, one can obtain stability data in full agreement with experimental observations, which envisage the applicability of QM in molecular design.

  6. Comparison of Bond in Roll-bonded and Adhesively Bonded Aluminums

    Science.gov (United States)

    Schwensfeir, R. J., Jr.; Trenkler, G.; Delagi, R. G.; Forster, J. A.

    1985-01-01

    Lap-shear and peel test measurements of bond strength have been carried out as part of an investigation of roll bonding of 2024 and 7075 aluminum alloys. Shear strengths of the bonded material in the F temper are in the range of 14 to 16 ksi. Corresponding peel strengths are 120 to 130 lb/inch. These values, which are three to five times those reported in the literature for adhesively bonded 2024 and 7075, are a result of the true metallurgical bond achieved. The effects of heat-treating the bonded material are described and the improvements in bond strength discussed relative to the shear strength of the parent material. The significance of the findings for aerospace applications is discussed.

  7. Interplay between Peptide Bond Geometrical Parameters in Nonglobular Structural Contexts

    Directory of Open Access Journals (Sweden)

    Luciana Esposito

    2013-01-01

    Full Text Available Several investigations performed in the last two decades have unveiled that geometrical parameters of protein backbone show a remarkable variability. Although these studies have provided interesting insights into one of the basic aspects of protein structure, they have been conducted on globular and water-soluble proteins. We report here a detailed analysis of backbone geometrical parameters in nonglobular proteins/peptides. We considered membrane proteins and two distinct fibrous systems (amyloid-forming and collagen-like peptides. Present data show that in these systems the local conformation plays a major role in dictating the amplitude of the bond angle N-Cα-C and the propensity of the peptide bond to adopt planar/nonplanar states. Since the trends detected here are in line with the concept of the mutual influence of local geometry and conformation previously established for globular and water-soluble proteins, our analysis demonstrates that the interplay of backbone geometrical parameters is an intrinsic and general property of protein/peptide structures that is preserved also in nonglobular contexts. For amyloid-forming peptides significant distortions of the N-Cα-C bond angle, indicative of sterical hidden strain, may occur in correspondence with side chain interdigitation. The correlation between the dihedral angles Δω/ψ in collagen-like models may have interesting implications for triple helix stability.

  8. 27 CFR 28.66 - Strengthening bonds.

    Science.gov (United States)

    2010-04-01

    ... bonds. In all cases where the penal sum of any bond becomes insufficient, the principal shall either give a strengthening bond with the same surety to attain a sufficient penal sum, or give a new bond to... of any bond to less than its full penal sum. Strengthening bonds shall show the current date...

  9. Materials integration for high-performance photovoltaics by wafer bonding

    Science.gov (United States)

    Zahler, James Michael

    The fundamental efficiency limit for state of the art triple-junction photovoltaic devices is being approached. By allowing integration of non-lattice-matched materials in monolithic structures, wafer bonding enables novel photovoltaic devices that have a greater number of subcells to improve the discretization of the solar spectrum, thus extending the efficiency limit of the devices. Additionally, wafer bonding enables the integration of non-lattice-matched materials with foreign substrates to confer desirable properties associated with the handle substrate on the solar cell structure, such as reduced mass, increased thermal conductivity, and improved mechanical toughness. This thesis outlines process development and characterization of wafer bonding integration technologies essential for transferring conventional triple-junction solar cell designs to potentially lower cost Ge/Si epitaxial templates. These epitaxial templates consist of a thin film of single-crystal Ge on a Si handle substrate. Additionally, a novel four-junction solar cell design consisting of non-lattice matched subcells of GaInP, GaAs, InGaAsP, and InGaAs based on InP/Si wafer-bonded epitaxial templates is proposed and InP/Si template fabrication and characterization is pursued. In this thesis the detailed-balance theory of the thermodynamic limiting performance of solar cell efficiency is applied to several device designs enabled by wafer bonding and layer exfoliation. The application of the detailed-balance theory to the novel four-junction cell described above shows that operating under 100 suns at 300 K a maximum efficiency of 54.9% is achievable with subcell bandgaps of 1.90, 1.42, 1.02, and 0.60 eV, a material combination achievable by integrating two wide-bandgap subcells lattice matched to GaAs and two narrow-bandgap subcells lattice matched to InP. Wafer bonding and layer transfer processes with sufficient quality to enable subsequent material characterization are demonstrated for both

  10. Glycine Substitutions in Collagen Heterotrimers Alter Triple Helical Assembly.

    Science.gov (United States)

    Clements, Katherine A; Acevedo-Jake, Amanda M; Walker, Douglas R; Hartgerink, Jeffrey D

    2017-02-13

    Osteogenesis imperfecta typically results from missense mutations in the collagen genome where the required glycine residues are replaced with another amino acid. Many models have attempted to replicate the structure of mutated collagen on the triple helix level. However, composition and register control of the triple helix is complicated and requires extreme precision, especially when these destabilizing mutations are present. Here we present mutations to a composition- and register-controlled AAB helix where one of the requisite glycines in the A chain of the triple helix is changed to serine or alanine. We see a loss of compositional control when the A chain is mutated, resulting in an A'BB composition that minimizes the number of mutations included in the triple helix. However, when both A and B chains are mutated and no nonmutated peptide chains are available, the designed A'A'B' composition is reestablished. Our work shows the ability of the mutations to influence and alter the composition and register of the collagen triple helix.

  11. Longitudinal Neuropsychological Profile in a Patient with Triple A Syndrome

    Directory of Open Access Journals (Sweden)

    Luigi Mazzone

    2013-01-01

    Full Text Available Triple A syndrome is an autosomal recessive disorder characterized by the triad of adrenocorticotropic hormone resistant adrenal insufficiency, achalasia, and alacrima. Our aim was to describe the neuropsychological characteristics and the cooccurring psychopathological and neurological disorders in an Italian male child suffering from Triple A syndrome at the time of admission (T0 and after one year of follow-up (T1. Many difficulties were observed in the motor domain, as well as in manual dexterity and static/dynamic balance domains of the motor task over time. In sharp contrast with previous literature reports on frequent mild cognitive dysfunction in patients with Triple A syndrome, our child did not show any mental retardation. By contrast, he showed an average IQ at T0 with a slight improvement at T1. To our knowledge, this report is the first describing neuropsychological profile and co-occurring psychopathological problems in a child with Triple A syndrome. Considering that the Triple A syndrome is a progressive disorder which can take years to develop the full-blown clinical picture, these patients require periodical medical controls. Moreover, assessment of neuropsychological and psychopathological features should be performed in patients with this disease, in order to underline the variability of this syndrome.

  12. The CALBC RDF Triple Store: retrieval over large literature content

    CERN Document Server

    Croset, Samuel; Li, Chen; Kavaliauskas, Silvestras; Rebholz-Schuhmann, Dietrich

    2010-01-01

    Integration of the scientific literature into a biomedical research infrastructure requires the processing of the literature, identification of the contained named entities (NEs) and concepts, and to represent the content in a standardised way. The CALBC project partners (PPs) have produced a large-scale annotated biomedical corpus with four different semantic groups through the harmonisation of annotations from automatic text mining solutions (Silver Standard Corpus, SSC). The four semantic groups were chemical entities and drugs (CHED), genes and proteins (PRGE), diseases and disorders (DISO) and species (SPE). The content of the SSC has been fully integrated into RDF Triple Store (4,568,678 triples) and has been aligned with content from the GeneAtlas (182,840 triples), UniProtKb (12,552,239 triples for human) and the lexical resource LexEBI (BioLexicon). RDF Triple Store enables querying the scientific literature and bioinformatics resources at the same time for evidence of genetic causes, such as drug ta...

  13. Collagen model peptides: Sequence dependence of triple-helix stability.

    Science.gov (United States)

    Persikov, A V; Ramshaw, J A; Brodsky, B

    2000-01-01

    The triple helix is a specialized protein motif, found in all collagens as well as in noncollagenous proteins involved in host defense. Peptides will adopt a triple-helical conformation if the sequence contains its characteristic features of Gly as every third residue and a high content of Pro and Hyp residues. Such model peptides have proved amenable to structural studies by x-ray crystallography and NMR spectroscopy, suitable for thermodynamic and kinetic analysis, and a valuable tool in characterizing the binding activities of the collagen triple helix. A systematic approach to understanding the amino acid sequence dependence of the collagen triple helix has been initiated, based on a set of host-guest peptides of the form, (Gly-Pro-Hyp)(3)-Gly-X-Y-(Gly-Pro-Hyp)(4). Comparison of their thermal stabilities has led to a propensity scale for the X and Y positions, and the additivity of contributions of individual residues is now under investigation. The local and global stability of the collagen triple helix is normally modulated by the residues in the X and Y positions, with every third position occupied by Gly in fibril-forming collagens. However, in collagen diseases, such as osteogenesis imperfecta, a single Gly may be substituted by another residue. Host-guest studies where the Gly is replaced by various amino acids suggest that the identity of the residue in the Gly position affects the degree of destabilization and the clinical severity of the disease.

  14. Ocular Problems in Triple-A Syndrome and Their Management

    Directory of Open Access Journals (Sweden)

    Seydi Okumuş

    2012-12-01

    Full Text Available Triple-A syndrome (Allgrove syndrome, is a rare autosomal recessive syndrome that is characterized by adrenal insufficiency, alacrimia and achalasia. In this report, we present a case of triple-A syndrome and discuss the ocular manifestations of the diseases along with evaluation of the therapeutic options. In addition to the classic triad of triple-A syndrome, our patient had intermittent exotropia. The patient was receiving oral steroids for adrenal insufficiency and artificial tear drops for eye dryness. Surgery was planned for exotropia. Punctum plug insertion was made simultaneously with bilateral lateral rectus recessions. Postoperative follow-up revealed near and distant horizontal deviation at the interval of ±10 PD. The patient’s complaints about eyes regressed significantly as well. Triple-A syndrome is a life threatening and rare disorder that could be fatal when undiagnosed. Punctum plugs are convenient therapy option for the treatment of xerophthalmia encountered in triple-A syndrome. With strabismus surgery including punctum plug insertion, any other surgery can be simultaneously carried out during a single session of general anesthesia. (Turk J Ophthalmol 2012; 42: 492-4

  15. Development of 600 kV triple resonance pulse transformer.

    Science.gov (United States)

    Li, Mingjia; Zhang, Faqiang; Liang, Chuan; Xu, Zhou

    2015-06-01

    In this paper, a triple-resonance pulse transformer based on an air-core transformer is introduced. The voltage across the high-voltage winding of the air-core transformer is significantly less than the output voltage; instead, the full output voltage appears across the tuning inductor. The maximum ratio of peak load voltage to peak transformer voltage is 2.77 in theory. By analyzing pulse transformer's lossless circuit, the analytical expression for the output voltage and the characteristic equation of the triple-resonance circuit are presented. Design method for the triple-resonance pulse transformer (iterated simulation method) is presented, and a triple-resonance pulse transformer is developed based on the existing air-core transformer. The experimental results indicate that the maximum ratio of peak voltage across the load to peak voltage across the high-voltage winding of the air-core transformer is approximately 2.0 and the peak output voltage of the triple-resonance pulse transformer is approximately 600 kV.

  16. Wafer bonding applications and technology

    CERN Document Server

    Gösele, Ulrich

    2004-01-01

    During the past decade direct wafer bonding has developed into a mature materials integration technology. This book presents state-of-the-art reviews of the most important applications of wafer bonding written by experts from industry and academia. The topics include bonding-based fabrication methods of silicon-on-insulator, photonic crystals, VCSELs, SiGe-based FETs, MEMS together with hybrid integration and laser lift-off. The non-specialist will learn about the basics of wafer bonding and its various application areas, while the researcher in the field will find up-to-date information about this fast-moving area, including relevant patent information.

  17. Photoinduced hydrogen-bonding dynamics.

    Science.gov (United States)

    Chu, Tian-Shu; Xu, Jinmei

    2016-09-01

    Hydrogen bonding dynamics has received extensive research attention in recent years due to the significant advances in femtolaser spectroscopy experiments and quantum chemistry calculations. Usually, photoexcitation would cause changes in the hydrogen bonding formed through the interaction between hydrogen donor and acceptor molecules on their ground electronic states, and such transient strengthening or weakening of hydrogen bonding could be crucial for the photophysical transformations and the subsequent photochemical reactions that occurred on a time scale from tens of femtosecond to a few nanoseconds. In this article, we review the combined experimental and theoretical studies focusing on the ultrafast electronic and vibrational hydrogen bonding dynamics. Through these studies, new mechanisms and proposals and common rules have been put forward to advance our understanding of the hydrogen bondings dynamics in a variety of important photoinduced phenomena like photosynthesis, dual fluorescence emission, rotational reorientation, excited-state proton transfer and charge transfer processes, chemosensor fluorescence sensing, rearrangements of the hydrogen-bond network including forming and breaking hydrogen bond in water. Graphical Abstract We review the recent advances on exploring the photoinduced hydrogen bonding dynamics in solutions through a joint approach of laser spectroscopy and theoretical calculation. The reviewed studies have put forward a new mechanism, new proposal, and new rule for a variety of photoinduced phenomena such as photosynthesis, dual fluorescence emission, rotational reorientation, excited-state proton transfer and charge transfer, chemosensor fluorescence sensing, and rearrangements of the hydrogen-bond network in water.

  18. Bond Growth under Temperature Gradient.

    Directory of Open Access Journals (Sweden)

    P.K. Satyawali

    1999-12-01

    Full Text Available Grain and bond growth for dry snow are determined by the distribution of temperature andtemperature gradient in the snow matrix. From the standpoint of particle approach and based oncubic packing structure, a bond growth model has been developed for TG metamorphism. The paper.highlights the importance of bond formation and its effect on snow viscosity and finally on the rateof settlement. This is very important for developing a numerical snow pack model if microstructureis considered to be a basic parameter. A few experiments have been carried out to validate bond formation under temperature gradient.

  19. A simplified indirect bonding technique

    Directory of Open Access Journals (Sweden)

    Radha Katiyar

    2014-01-01

    Full Text Available With the advent of lingual orthodontics, indirect bonding technique has become an integral part of practice. It involves placement of brackets initially on the models and then their transfer to teeth with the help of transfer trays. Problems encountered with current indirect bonding techniques used are (1 the possibility of adhesive flash remaining around the base of the brackets which requires removal (2 longer time required for the adhesive to gain enough bond strength for secure tray removal. The new simplified indirect bonding technique presented here overcomes both these problems.

  20. Effect of intracanal medicaments on push-out bond strength of Smart-Seal system

    Directory of Open Access Journals (Sweden)

    Vibha Hegde

    2015-01-01

    Full Text Available Aim: To evaluate the effects of calcium hydroxide (CH, triple and double antibiotic pastes (DAPs on the bond strength of Smart-Seal obturation, C-points with Endosequence Bio-ceramic (BC sealer to the root canal dentin. Materials and Methods: Sixty-four freshly extracted single-rooted human mandibular premolars were de-coronated and prepared using rotary Pro-taper system with full sequence till F3. The specimens were randomly divided into a control group (without intracanal dressing and 3 experimental groups that received an intracanal dressing with either CH, DAP, or triple antibiotic paste (TAP (n = 16. The intracanal dressing was removed after 3 weeks by rinsing with 10 mL 17% ethylenediaminetetraacetic acid, followed by 10 mL 3% sodium hypochlorite. The root canals were then obturated with C-points and Endosequence BC sealer. A push-out test was used to measure the bond strength between the root canal dentin and the obturating system. The data were analyzed using two-way analysis of variance and Tukey post-hoc test. Results: The push-out bond strength values were significantly affected by the intracanal medicaments (P 0.05. In the middle and apical third, the bond strength of the TAP group was higher than those of the CH and DAP groups (P < 0.05. Conclusions: The DAP and CH did not affect the bond strength of the novel hydrophilic obutrating system. TAP improved the bond strength of Smart-Seal system in the middle and apical thirds.

  1. Reactive Bonding Film for Bonding Carbon Foam Through Metal Extrusion

    CERN Document Server

    Chertok, Maxwell; Irving, Michael; Neher, Christian; Tripathi, Mani; Wang, Ruby; Zheng, Gayle

    2016-01-01

    Future tracking detectors, such as those under development for the High Luminosity LHC, will require mechanical structures employing novel materials to reduce mass while providing excellent strength, thermal conductivity, and radiation tolerance. Adhesion methods for such materials are under study at present. This paper demonstrates the use of reactive bonding film as an adhesion method for bonding carbon foam.

  2. Digital Control of Bonding Force for Gold Wire Bonding Machine

    Directory of Open Access Journals (Sweden)

    Xiaochu Wang

    2013-01-01

    Full Text Available In order to digitally control the bonding force of a wire bonder precisely, this paper uses a DC solenoid as a force source, and by controlling the solenoid’s current, which causes the electromagnetic force, we can control the bonding force that capillary applies. The bonding force control system in this paper is composed of PC (Personal Computer and hypogyny MCU (Micro Controller Unit, which communicate using a RS485 interface. The digital value of a given bonding force is given by the PC to the MCU. By comparing the sampling current of the solenoid, and through PID regulation, D/A converter of the digital potentiometer and the solenoid driver circuit, the half-closed loop control system of bonding force is accomplished. Tuning of the PID parameters is accomplished with fuzzy adaptive control theory and simulated by Matlab simulink. The control system is tested by comparing the desired bonding force and the force actually applied and examming the relationship between bonding quality and bonding force.

  3. 29 CFR 2580.412-19 - Term of the bond, discovery period, other bond clauses.

    Science.gov (United States)

    2010-07-01

    ... SECURITY ACT OF 1974 TEMPORARY BONDING RULES General Bond Rules § 2580.412-19 Term of the bond, discovery... 29 Labor 9 2010-07-01 2010-07-01 false Term of the bond, discovery period, other bond clauses... new bond must be obtained each year. There is nothing in the Act that prohibits a bond for a...

  4. Optical frequency tripling with improved suppression and sideband selection.

    Science.gov (United States)

    Thakur, Manoj P; Medeiros, Maria C R; Laurêncio, Paula; Mitchell, John E

    2011-12-12

    A novel optical dispersion tolerant millimetre-wave radio-over-fibre system using optical frequency tripling technique with enhanced and selectable sideband suppression is demonstrated. The implementation utilises cascaded optical modulators to achieve either an optical single sideband (OSSB) or double sideband-suppressed carrier (DSB-SC) signal with high sideband suppression. Our analysis and simulation results indicate that the achievable suppression ratio of this configuration is only limited by other system factors such as optical noise and drifting of the operational conditions. The OSSB transmission system performance is assessed experimentally by the transport of 4 WiMax channels modulating a 10 GHz optical upconverted RF carrier as well as for optical frequency doubling and tripling. The 10 GHz and tripled carrier at 30 GHz are dispersion tolerant resulting both in an average relative constellation error (RCE) of -28.7 dB after 40 km of fibre.

  5. Pulsed electron-nuclear-electron triple resonance spectroscopy

    Science.gov (United States)

    Thomann, Hans; Bernardo, Marcelino

    1990-05-01

    A new experimental technique, pulsed electron-nuclear-electron triple resonance spectroscopy, is demonstrated. It is based on a modification of the pulse sequence for electron-nuclear double resonance (ENDOR) in which two EPR and one NMR transition are irradiated. The irradiation of one EPR transition is detected via a second EPR transition. The nuclear hyperfine coupling, which separates these EPR transition frequencies, is the irradiated NMR transition. The major advantages of triple resonance spectroscopy include the ability to resolve overlapping nuclear resonances in the ENDOR spectrum and a more direct quantitative assignment of nuclear hyperfine and quadrupole couplings. The triple resonance experiment is an alternative to the recently proposed method of employing rapid magnetic field jumps between microwave pulses for generating hyperfine selective ENDOR spectra.

  6. On universality of scaling law describing roughness of triple line.

    Science.gov (United States)

    Bormashenko, Edward; Musin, Albina; Whyman, Gene; Barkay, Zahava; Zinigrad, Michael

    2015-01-01

    The fine structure of the three-phase (triple) line was studied for different liquids, various topographies of micro-rough substrates and various wetting regimes. Wetting of porous and pillar-based micro-scaled polymer surfaces was investigated. The triple line was visualized with the environmental scanning electron microscope and scanning electron microscope for the "frozen" triple lines. The value of the roughness exponent ζ for water (ice)/rough polymer systems was located within 0.55-0.63. For epoxy glue/rough polymer systems somewhat lower values of the exponent, 0.42 switch of the exponent, when the roughness size approaches to the correlation length of the defects, is also universal.

  7. The Knowledge-Based Economy and the Triple Helix Model

    CERN Document Server

    Leydesdorff, Loet

    2012-01-01

    1. Introduction - the metaphor of a "knowledge-based economy"; 2. The Triple Helix as a model of the knowledge-based economy; 3. Knowledge as a social coordination mechanism; 4. Neo-evolutionary dynamics in a Triple Helix of coordination mechanism; 5. The operation of the knowledge base; 6. The restructuring of knowledge production in a KBE; 7. The KBE and the systems-of-innovation approach; 8. The KBE and neo-evolutionary theories of innovation; 8.1 The construction of the evolving unit; 8.2 User-producer relations in systems of innovation; 8.3 'Mode-2' and the production of scientific knowledge; 8.4 A Triple Helix model of innovations; 9. Empirical studies and simulations using the TH model; 10. The KBE and the measurement; 10.1 The communication of meaning and information; 10.2 The expectation of social structure; 10.3 Configurations in a knowledge-based economy

  8. The Algol triple system spatially resolved at optical wavelengths

    CERN Document Server

    Zavala, R T; Boboltz, D A; Ojha, R; Shaffer, D B; Tycner, C; Richards, M T; Hutter, D J; 10.1088/2041-8205/715/1/L44

    2010-01-01

    Interacting binaries typically have separations in the milli-arcsecond regime and hence it has been challenging to resolve them at any wavelength. However, recent advances in optical interferometry have improved our ability to discern the components in these systems and have now enabled the direct determination of physical parameters. We used the Navy Prototype Optical Interferometer to produce for the first time images resolving all three components in the well-known Algol triple system. Specifically, we have separated the tertiary component from the binary and simultaneously resolved the eclipsing binary pair, which represents the nearest and brightest eclipsing binary in the sky. We present revised orbital elements for the triple system, and we have rectified the 180-degree ambiguity in the position angle of Algol C. Our directly determined magnitude differences and masses for this triple star system are consistent with earlier light curve modeling results.

  9. On the Interface Formation Model for Dynamic Triple Lines

    CERN Document Server

    Bothe, Dieter

    2015-01-01

    This paper revisits the theory of Y. Shikhmurzaev on forming interfaces as a continuum thermodynamical model for dynamic triple lines. We start with the derivation of the balances for mass, momentum, energy and entropy in a three-phase fluid system with full interfacial physics, including a brief review of the relevant transport theorems on interfaces and triple lines. Employing the entropy principle in the form given in [Bothe & Dreyer, Acta Mechanica, doi:10.1007/s00707-014-1275-1] but extended to this more general case, we arrive at the entropy production and perform a linear closure, except for a nonlinear closure for the sorption processes. Specialized to the isothermal case, we obtain a thermodynamically consistent mathematical model for dynamic triple lines and show that the total available energy is a strict Lyapunov function for this system.

  10. Triple inhaled therapy for chronic obstructive pulmonary disease.

    Science.gov (United States)

    Montuschi, Paolo; Malerba, Mario; Macis, Giuseppe; Mores, Nadia; Santini, Giuseppe

    2016-11-01

    Combining individual drugs in a single inhaler is the most convenient way to deliver triple therapy. A long-acting muscarinic receptor antagonist (LAMA) added to an inhaled corticosteroid (ICS)/long-acting β2-adrenoceptor agonist (LABA) fixed-dose combination (FDC) can improve efficacy of pharmacological treatment of patients with chronic obstructive pulmonary disease (COPD). New inhaled ICS/LABA/LAMA FDCs, including fluticasone furoate/vilanterol/umeclidinium, budesonide/formoterol/glycopyrronium and beclometasone/formoterol/glycopyrronium, are in Phase III of clinical development for COPD. Triple inhaled therapy might be particularly useful in patients with severe to very severe COPD, above all in those with peripheral blood or sputum eosinophilia, asthma-COPD overlap syndrome (ACOS) or frequent exacerbators. Future prospective studies should assess efficacy and safety of triple ICS/LABA/LAMA therapy in selected COPD phenotypes.

  11. The evolution of hierarchical triple star-systems

    Science.gov (United States)

    Toonen, Silvia; Hamers, Adrian; Portegies Zwart, Simon

    2016-12-01

    Field stars are frequently formed in pairs, and many of these binaries are part of triples or even higher-order systems. Even though, the principles of single stellar evolution and binary evolution, have been accepted for a long time, the long-term evolution of stellar triples is poorly understood. The presence of a third star in an orbit around a binary system can significantly alter the evolution of those stars and the binary system. The rich dynamical behaviour in three-body systems can give rise to Lidov-Kozai cycles, in which the eccentricity of the inner orbit and the inclination between the inner and outer orbit vary periodically. In turn, this can lead to an enhancement of tidal effects (tidal friction), gravitational-wave emission and stellar interactions such as mass transfer and collisions. The lack of a self-consistent treatment of triple evolution, including both three-body dynamics as well as stellar evolution, hinders the systematic study and general understanding of the long-term evolution of triple systems. In this paper, we aim to address some of these hiatus, by discussing the dominant physical processes of hierarchical triple evolution, and presenting heuristic recipes for these processes. To improve our understanding on hierarchical stellar triples, these descriptions are implemented in a public source code TrES, which combines three-body dynamics (based on the secular approach) with stellar evolution and their mutual influences. Note that modelling through a phase of stable mass transfer in an eccentric orbit is currently not implemented in TrES, but can be implemented with the appropriate methodology at a later stage.

  12. Critical Curves and Caustics of Triple-lens Models

    Science.gov (United States)

    Daněk, Kamil; Heyrovský, David

    2015-06-01

    Among the 25 planetary systems detected up to now by gravitational microlensing, there are two cases of a star with two planets, and two cases of a binary star with a planet. Other, yet undetected types of triple lenses include triple stars or stars with a planet with a moon. The analysis and interpretation of such events is hindered by the lack of understanding of essential characteristics of triple lenses, such as their critical curves and caustics. We present here analytical and numerical methods for mapping the critical-curve topology and caustic cusp number in the parameter space of n-point-mass lenses. We apply the methods to the analysis of four symmetric triple-lens models, and obtain altogether 9 different critical-curve topologies and 32 caustic structures. While these results include various generic types, they represent just a subset of all possible triple-lens critical curves and caustics. Using the analyzed models, we demonstrate interesting features of triple lenses that do not occur in two-point-mass lenses. We show an example of a lens that cannot be described by the Chang-Refsdal model in the wide limit. In the close limit we demonstrate unusual structures of primary and secondary caustic loops, and explain the conditions for their occurrence. In the planetary limit we find that the presence of a planet may lead to a whole sequence of additional caustic metamorphoses. We show that a pair of planets may change the structure of the primary caustic even when placed far from their resonant position at the Einstein radius.

  13. Differential stability of the triple helix of (Pro-Pro-Gly)10 in H2O and D2O: thermodynamic and structural explanations.

    Science.gov (United States)

    Gough, C A; Bhatnagar, R S

    1999-12-01

    (Pro-Pro-Gly)10 [(PPG10)], a collagen-like polypeptide, forms a triple-helical, polyproline-II structure in aqueous solution at temperatures somewhat lower than physiological, with a melting temperature of 24.5 degrees C. In this article, we present circular dichroism spectra that demonstrate an increase of the melting temperature with the addition of increasing amounts of D2O to an H2O solution of (PPG)10, with the melting temperature reaching 40 degrees C in pure D2O. A thermodynamic analysis of the data demonstrates that this result is due to an increasing enthalpy of unfolding in D2O vs. H2O. To provide a theoretical explanation for this result, we have used a model for hydration of (PPG)10 that we developed previously, in which inter-chain water bridges are formed between sterically crowded waters and peptide bond carbonyls. Energy minimizations were performed upon this model using hydrogen bond parameters for water, and altered hydrogen bond parameters that reproduced the differences in carbonyl oxygen-water oxygen distances found in small-molecule crystal structures containing oxygen-oxygen hydrogen bonds between organic molecules and H2O or D2O. It was found that using hydrogen bond parameters that reproduced the distance typical of hydrogen bonds to D2O resulted in a significant lowering of the potential energy of hydrated (PPG)10. This lowering of the energy involved energetic terms that were only indirectly related to the altered hydrogen bond parameters, and were therefore not artifactual; the intra-(PPG10) energy, plus the water-(PPG10) van der Waals energy (not including hydrogen bond interactions), were lowered enough to qualitatively account for the lower enthalpy of the triple-helical conformation, relative to the unfolded state, in D2O vs. H2O. This result indicates that the geometry of the carbonyl-D2O hydrogen bonds allows formation of good hydrogen bonds without making as much of an energetic sacrifice from other factors as in the case of

  14. Pauling bond strength, bond length and electron density distribution

    Energy Technology Data Exchange (ETDEWEB)

    Gibbs, Gerald V.; Ross, Nancy L.; Cox, David F.; Rosso, Kevin M.; Iversen, Bo B.; Spackman, M. A.

    2014-01-18

    A power law regression equation, = 1.46(<ρ(rc)>/r)-0.19, connecting the average experimental bond lengths, , with the average accumulation of the electron density at the bond critical point, <ρ(rc)>, between bonded metal M and oxygen atoms, determined at ambient conditions for oxide crystals, where r is the row number of the M atom, is similar to the regression equation R(M-O) = 1.39(ρ(rc)/r)-0.21 determined for three perovskite crystals for pressures as high as 80 GPa. The two equations are also comparable with those, = 1.43(/r)-0.21, determined for a large number of oxide crystals at ambient conditions and = 1.39(/r)-0.22, determined for geometry optimized hydroxyacid molecules, that connect the bond lengths to the average Pauling electrostatic bond strength, , for the M-O bonded interactions. On the basis of the correspondence between the two sets of equations connecting ρ(rc) and the Pauling bond strength s with bond length, it appears that Pauling’s simple definition of bond strength closely mimics the accumulation of the electron density between bonded pairs of atoms. The similarity of the expressions for the crystals and molecules is compelling evidence that the M-O bonded interactions for the crystals and molecules 2 containing the same bonded interactions are comparable. Similar expressions, connecting bond lengths and bond strength, have also been found to hold for fluoride, nitride and sulfide molecules and crystals. The Brown-Shannon bond valence, σ, power law expression σ = [R1/(R(M-O)]N that has found wide use in crystal chemistry, is shown to be connected to a more universal expression determined for oxides and the perovskites, <ρ(rc)> = r[(1.41)/]4.76, demonstrating that the bond valence for a bonded interaction is likewise closely connected to the accumulation of the electron density between the bonded atoms. Unlike the Brown-Shannon expression, it is universal in that it holds for the M

  15. On Pythagoras' theorem for products of spectral triples

    CERN Document Server

    D'Andrea, Francesco

    2012-01-01

    We discuss a version of Pythagoras' theorem in noncommutative geometry. Starting from a formulation of the theorem in terms of Connes' distance, between pure states, in the product of commutative spectral triples, we show that for non-pure states it is replaced by some Pythagoras inequalities. We prove the latter in full generality, that is for the product of arbitrary (i.e. non-necessarily commutative) unital spectral triples. Moreover we show that the inequalities are optimal, and provide non-unital counter-examples inspired by K-homology.

  16. Triple-mode squeezing with dressed six-wave mixing.

    Science.gov (United States)

    Wen, Feng; Li, Zepei; Zhang, Yiqi; Gao, Hong; Che, Junling; Che, Junling; Abdulkhaleq, Hasan; Zhang, Yanpeng; Wang, Hongxing

    2016-05-12

    The theory of proof-of-principle triple-mode squeezing is proposed via spontaneous parametric six-wave mixing process in an atomic-cavity coupled system. Special attention is focused on the role of dressed state and nonlinear gain on triple-mode squeezing process. Using the dressed state theory, we find that optical squeezing and Autler-Towns splitting of cavity mode can be realized with nonlinear gain, while the efficiency and the location of maximum squeezing point can be effectively shaped by dressed state in atomic ensemble. Our proposal can find applications in multi-channel communication and multi-channel quantum imaging.

  17. Studying the triple - α reaction in hyperspherical harmonic approach

    Science.gov (United States)

    Nguyen, Ngoc; Nunes, Filomena

    2010-11-01

    The triple-α reaction is studied by using hyperspherical harmonic (HH) method [1]. Starting from three body model, we determine the 2^+ state and the 0^+ resonance as well as the quadrupole strength function B(E2). The triple-α reaction rate are calculated. We also carefully consider the contributions of the nonresonant continuum states to the reaction rate at low temperature (T Ogata, M.Kan, M.Kamimura, Prog. Theor. Phys. 122, 1055 (2009).[0pt] [3] R. de Diego, E. Garrido, D.V. Fedorov, A.S. Jensen, arXiv:1005.5647v1.

  18. A Remark on Gelfand Duality for Spectral Triples

    CERN Document Server

    Bertozzini, Paolo; Lewkeeratiyutkul, Wicharn

    2008-01-01

    We present a duality between the category of compact Riemannian spin manifolds (equipped with a given spin bundle and charge conjugation) with isometries as morphisms and a suitable "metric" category of spectral triples over commutative pre-C*-algebras. We also construct an embedding of a "quotient" of the category of spectral triples introduced in arXiv:math/0502583v1 into the latter metric category. Finally we discuss a further related duality in the case of orientation and spin-preserving maps between manifolds of fixed dimension.

  19. Spectral triples and differential calculi related to the Kronecker foliation

    Science.gov (United States)

    Matthes, R.; Richter, O.; Rudolph, G.

    2003-04-01

    Following the ideas of Connes and Moscovici, we describe two spectral triples related to the Kronecker foliation, whose generalized Dirac operators are related to first and second order signature operators. We also consider the corresponding differential calculi Ω D, which are drastically different in the two cases. For the second order signature operator we calculate the Chern character of the spectral triple and the Dixmier trace of certain powers of its Dirac operator. As a side-remark, we give a description of a known calculus on the two-dimensional noncommutative torus in terms of generators and relations.

  20. Non-resonant triple alpha reaction rate at low temperature

    Energy Technology Data Exchange (ETDEWEB)

    Itoh, T.; Tamii, A.; Aoi, N.; Fujita, H.; Hashimoto, T.; Miki, K.; Ogata, K. [Research Center for Nuclear Physics, Osaka University, Ibaraki, Osaka 567-0047 (Japan); Carter, J.; Donaldson, L.; Sideras-Haddad, E. [Schools of Physics, University of Witwatersrand, Johannesburg 2050 (South Africa); Furuno, T.; Kawabata, T. [Departments of Physics, Kyoto University, Sakyo, Kyoto, 606-8502 (Japan); Kamimura, M. [RIKEN Nishina Center, Wako, Saitama, 351-0198 (Japan); Nemulodi, F.; Neveling, R.; Smit, F. D.; Swarts, C. [iThemba Laboratory for Accelerator Based Sciences Somerset, West, 7129 (South Africa)

    2014-05-02

    Our experimental goal is to study the non-resonant triple alpha reaction rate at low temperture (T < 10{sup 8} K). The {sup 13}C(p,d) reaction at 66 MeV has been used to probe the alpha-unbound continuum state in {sup 12}C just below the 2{sup nd} 0{sup +} state at 7.65 MeV. The transition strength to the continuum state is predicted to be sensitive to the non-resonant triple alpha reaction rate. The experiment has been performed at iThemba LABS. We report the present status of the experiment.

  1. Triple pelvic osteotomy in the treatment of hip dysplasia

    Directory of Open Access Journals (Sweden)

    Vukašinović Zoran

    2009-01-01

    Full Text Available Introduction. Insufficient femoral head coverage is found in a variety of diseases, with acetabular dysplasia as the most frequent disorder and triple pelvic osteotomy as the most recently introduced surgical treatment. Objective. This study analyses pre- and postoperative pathoanatomic characteristics of triple in comparison to Salter and Chiari osteotomies, with a logistic regression analysis of outcome predictor and effect explanator factors in relation to the chosen type of operation. Methods. The study involved 136 adolescents treated with Salter and Chiari osteotomies or a triple pelvic osteotomy at the Institute of Orthopaedic Surgery 'Banjica' in Belgrade. The patients were between 10-20 years old at the time of operation. We collected and analyzed data from all the patients: illness history, operative parameters, preoperative and postoperative pathoanatomic data. The data was statistically processed using the statistical software SPSS, defining standard descriptive values, and by using the appropriate tests of analytic statistics: t-test for dependent and independent variables, χ2-test, Fisher's exact test, Wilcoxon's test, parameter correlation, one-way ANOVA, multi-factorial ANOVA and logistic regression, according to the type of the analyzed data and the conditions under which the statistical methods were applied. Results. The average CE angle after triple pelvic osteotomy was 43.5°, more improved than after the Salter osteotomy (33.0° and Chiari osteotomy (31.4° (F=16.822; p<0.01. Postoperative spherical congruence was also more frequent after the triple osteotomy than after the other two types of operations, and with a high significance. Preoperative painful discomfort was found to be a valid predictor of indications for the triple osteotomy over both Chiari and Salter osteotomies. The valid explanators of effect for the triple osteotomy are: postoperative joint congruence (compared to the Chiari osteotomy and increase in joint

  2. Optimal Investment in Structured Bonds

    DEFF Research Database (Denmark)

    Jessen, Pernille; Jørgensen, Peter Løchte

    2012-01-01

    of the article is to provide possible explanations for the puzzle of why small retail investors hold structured bonds. The investment universe consists of a stock index, a risk-free bank account, and a structured bond containing an option written on another index. We apply expected utility maximization...

  3. Computational Chemistry of Adhesive Bonds

    Science.gov (United States)

    Phillips, Donald H.

    1999-01-01

    This investigation is intended to determine the electrical mechanical, and chemical properties of adhesive bonds at the molecular level. The initial determinations will be followed by investigations of the effects of environmental effects on the chemistry and properties of the bond layer.

  4. SOCIAL BONDING: REGULATION BY NEUROPEPTIDES

    Directory of Open Access Journals (Sweden)

    Claudia eLieberwirth

    2014-06-01

    Full Text Available Affiliative social relationships (e.g., among spouses, family members, and friends play an essential role in human society. These relationships affect psychological, physiological, and behavioral functions. As positive and enduring bonds are critical for the overall well-being of humans, it is not surprising that considerable effort has been made to study the neurobiological mechanisms that underlie social bonding behaviors. The present review details the involvement of the nonapeptides, oxytocin (OT and arginine vasopressin (AVP, in the regulation of social bonding in mammals including humans. In particular, we will discuss the role of OT and AVP in the formation of social bonds between partners of a mating pair as well as between parents and their offspring. Furthermore, the role of OT and AVP in the formation of interpersonal bonding involving trust is also discussed.

  5. Quaternary Evolution of Karliova Triple Junction

    Science.gov (United States)

    Sançar, Taylan; Zabcı, Cengiz; Akyüz, H. Serdar

    2013-04-01

    The arguments to explain Quaternary evolution of Karlıova Triple Junction (KTJ) depends upon two different analogue models. The compressional type of Prandtl Cell Model (PCM) and 60 km wide shear zone with concomitant counter clockwise block rotation used to modelled for west and east of the KTJ respectively. The data for the model of west of the KTJ acquired by extensive field studies, and quantified geomorphic features. Compressional PCM put forward that behavior of slip lines controlled by boundary faults. But the model is not enough to explain slip distribution, age relation of them. At west of the KTJ boundary faults presented by eastern most segments of the North Anatolian Fault Zone (NAFZ) and the East Anatolian Fault Zone (EAFZ). Slip lines, however, presented by Bahçeli and Toklular faults. Both field studies and morphometric analyses undisputedly set forth that there are two different fault types between the NAFZ and EAFZ. The most strain loaded fault type, which are positioned near the NAFZ, start as a strike-slip fault and when it turn to SE its sense of motion change to oblique normal due to changing orientation of principal stress axes. The new orientation of stress axes exposed in the field as a special kind of caprock -cuesta-. The younger slip lines formed very close to junction point and accommodate less slip. Even though slip trajectories started from the boundary faults in compressional PCM, at the west of KTJ, right lateral trajectories more clearly formed close the NAFZ and left lateral trajectories, relatively less strain loaded fault type, are poorly formed close the EAFZ . We think that, this differences between KTJ and compressional PCM result from the distinction of velocity of boundary faults. East of the KTJ governed by completely different mechanism. The region controlled two main fault systems. The Varto Fault Zone (VFZ), the eastern branch of the KTJ, and Murat Fault (MF) delimited the region from north and south respectively. The

  6. Dentin-bonding agents

    Directory of Open Access Journals (Sweden)

    João Carlos Gomes

    2008-01-01

    Full Text Available New dental restorative materials have been developed to meet not only the functional demands, but esthetics as well, and in the last few years an enormous range of new materials has appeared for use in dentistry. Among them, several adhesive systems, and different operative techniques for each group materials. Therefore, is indispensable for the professional to know about the properties, characteristics, and association of these materials with the dental structures, in order to select and use them correctly. Should conventional self-etching adhesive systems be used? This question encouraged this literature review to be conducted, with the aim of comparing the conventional adhesive systems with the self-etching systems and to look for scientific data that would help professionals to choose which adhesive system to use. When compared to conventional systems, it was noted that the self-etching systems show less sensitivity to technique, especially as regards errors the operator could commit. The self-etching systems, particularly the 2-step type, have shown equivalent values of bond strength, marginal microleakage and performance, therefore, will be an option for direct composite resin restorations in posterior teeth.

  7. A Lagrangian framework for deriving triples and quadruples corrections to the CCSD energy

    DEFF Research Database (Denmark)

    Eriksen, Janus Juul; Kristensen, Kasper; Kjærgaard, Thomas;

    2014-01-01

    Using the coupled cluster Lagrangian technique, we have determined perturbative corrections to the coupled cluster singles and doubles (CCSD) energy that converge towards the coupled cluster singles, doubles, and triples (CCSDT) and coupled cluster singles, doubles, triples, and quadruples (CCSDT...

  8. Polymorphism of collagen triple helix revealed by 19F NMR of model peptide [Pro-4(R)-hydroxyprolyl-Gly]3-[Pro-4(R)-fluoroprolyl-Gly]-[Pro-4(R)-hydroxyprolyl-Gly]3.

    Science.gov (United States)

    Kawahara, Kazuki; Nemoto, Nobuaki; Motooka, Daisuke; Nishi, Yoshinori; Doi, Masamitsu; Uchiyama, Susumu; Nakazawa, Takashi; Nishiuchi, Yuji; Yoshida, Takuya; Ohkubo, Tadayasu; Kobayashi, Yuji

    2012-06-14

    We have characterized various structures of (Pro-Hyp(R)-Gly)(3)-Pro-fPro(R)-Gly-(Pro-Hyp(R)-Gly)(3) in the process of cis-trans isomerization and helix-coil transition by exploiting the sole (19)F NMR probe in 4(R)-fluoroproline (fPro(R)). Around the transition temperature (T(m)), we detected a species with a triple helical structure distinct from the ordinary one concerning the alignment of three strands. The (19)F-(19)F exchange spectroscopy showed that this misaligned and that the ordinary triple helices were interchangeable only indirectly via an extended monomer strand with all-trans peptide bonds at Pro-fPro(R), Pro-Hyp(R), and Gly-Pro in the central segment. This finding demonstrates that the helix-coil transition of collagen peptides is not described with a simple two-state model. We thus elaborated a scheme for the transition mechanism of (Pro-Hyp(R)-Gly)(n) that the most extended monomer strand can be the sole source both to the misaligned and correctly folded triple-helices. The staggered ends could help misaligned triple helices to self-assemble to higher-order structures. We have also discussed the possible relationship between the misaligned triple helix accumulating maximally at T(m) and the kinetic hysteresis associated with the helix-coil transition of collagen.

  9. Phase behavior of self-associating fluids with weaker dispersion interactions between bonded particles.

    Science.gov (United States)

    Talanquer, V

    2005-04-15

    In this study, we explore the global phase behavior of a simple model for self-associating fluids where association reduces the strength of the dispersion interactions between bonded particles. Recent research shows that this type of behavior likely explains the thermodynamic properties of strongly polar fluids and certain micellar solutions. Based on Wertheim's theory of associating liquids [M. S. Wertheim, J. Stat. Phys. 42, 459 (1986); 42, 477 (1986)], our model takes into account the effect that dissimilar particle interactions have on the equilibrium constant for self-association in the system. We find that weaker interactions between bonded molecules tend to favor the dissociation of chains at any temperature and density. This effect stabilizes a monomeric liquid phase at high densities, enriching the global phase behavior of the system. In particular, for systems in which the energy of mixing between bonded and unbonded species is positive, we find a triple point involving a vapor, a dense phase of chain aggregates, and a monomeric liquid. Phase coexistence between the vapor and the monomeric fluid is always more stable at temperatures above the triple point, but a highly associated fluid may exist as a metastable phase under these conditions. The presence of this metastable phase may explain the characteristic nucleation behavior of the liquid phase in strongly dipolar fluids.

  10. 27 CFR 24.153 - Strengthening bonds.

    Science.gov (United States)

    2010-04-01

    ... Strengthening bonds. In any instance where the penal sum of the bond on file becomes insufficient, the principal shall either give a strengthening bond with the same surety to attain a sufficient penal sum or give a... limiting the amount of either bond to less than its full penal sum. Strengthening bonds will show...

  11. 27 CFR 19.246 - Strengthening bonds.

    Science.gov (United States)

    2010-04-01

    ... Strengthening bonds. In all cases when the penal sum of any bond becomes insufficient, the principal shall either give a strengthening bond with the same surety to attain a sufficient penal sum, or give a new... amount of any bond to less than its full penal sum. Strengthening bonds shall show the current date...

  12. Hoogsteen-position pyrimidines promote the stability and function of the MALAT1 RNA triple helix.

    Science.gov (United States)

    Brown, Jessica A; Kinzig, Charles G; DeGregorio, Suzanne J; Steitz, Joan A

    2016-05-01

    Triple-stranded RNA was first deduced to form in vitro more than 50 years ago and has since been implicated in RNA catalysis, stability, and small molecule binding. Despite the emerging biological significance of RNA triple helices, it remains unclear how their nucleotide composition contributes to their thermodynamic stability and cellular function. To investigate these properties, we used in vitro RNA electrophoretic mobility shift assays (EMSAs) and in vivo intronless β-globin reporter assays to measure the relative contribution of 20 RNA base triples (N•A-U, N•G-C, N•C-G, N•U-A, and N•G-U) to triple-helical stability. These triples replaced a single internal U•A-U within the known structure of the triple-helical RNA stability element of human metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), which contains 10 major-groove base triples. In addition to the canonical C•G-C triple, the noncanonical base triples U•G-C, U•G-U, C•C-G, and U•C-G exhibited at least 30% stability relative to the wild-type U•A-U base triple in both assays. Of these triples, only U•A-U, C•G-C, and U•G-C, when tested as four successive triples, formed stabilizing structures that allowed accumulation of the intronless β-globin reporter. Overall, we find that Hoogsteen-position pyrimidines support triple helix stability and function and that thermodynamic stability, based on EMSA results, is necessary but not sufficient for stabilization activity of the MALAT1 triple helix in cells. These results suggest that additional RNA triple helices containing noncanonical triples likely exist in nature.

  13. Nearby low-mass triple system GJ795

    CERN Document Server

    Malogolovets, E V; Rastegaev, D A; Balega, Yu.Yu.

    2007-01-01

    We report the results of our optical speckle-interferometric observations of the nearby triple system GJ795 performed with the 6-m BTA telescope with diffraction-limited angular resolution. The three components of the system were optically resolved for the first time. Position measurements allowed us to determine the elements of the inner orbit of the triple system. We use the measured magnitude differences to estimate the absolute magnitudes and spectral types of the components of the triple: $M_{V}^{Aa}$=7.31$\\pm$0.08, $M_{V}^{Ab}$=8.66$\\pm$0.10, $M_{V}^{B}$=8.42$\\pm$0.10, $Sp_{Aa}$ $\\approx$K5, $Sp_{Ab}$ $\\approx$K9, $Sp_{B}$ $\\approx$K8. The total mass of the system is equal to $\\Sigma\\mathcal{M}_{AB}$=1.69$\\pm0.27\\mathcal{M}_{\\odot}$. We show GJ795 to be a hierarchical triple system which satisfies the empirical stability criteria.

  14. Peptide tessellation yields micrometre-scale collagen triple helices

    Science.gov (United States)

    Tanrikulu, I. Caglar; Forticaux, Audrey; Jin, Song; Raines, Ronald T.

    2016-11-01

    Sticky-ended DNA duplexes can associate spontaneously into long double helices; however, such self-assembly is much less developed with proteins. Collagen is the most prevalent component of the extracellular matrix and a common clinical biomaterial. As for natural DNA, the ~103-residue triple helices (~300 nm) of natural collagen are recalcitrant to chemical synthesis. Here we show how the self-assembly of short collagen-mimetic peptides (CMPs) can enable the fabrication of synthetic collagen triple helices that are nearly a micrometre in length. Inspired by the mathematics of tessellations, we derive rules for the design of single CMPs that self-assemble into long triple helices with perfect symmetry. Sticky ends thus created are uniform across the assembly and drive its growth. Enacting this design yields individual triple helices that, in length, match or exceed those in natural collagen and are remarkably thermostable, despite the absence of higher-order association. The symmetric assembly of CMPs provides an enabling platform for the development of advanced materials for medicine and nanotechnology.

  15. Organizing product innovation: hierarchy, market or triple-helix networks?

    Science.gov (United States)

    Fitjar, Rune Dahl; Gjelsvik, Martin; Rodríguez-Pose, Andrés

    This paper assesses the extent to which the organization of the innovation effort in firms, as well as the geographical scale at which this effort is pursued, affects the capacity to benefit from product innovations. Three alternative modes of organization are studied: hierarchy, market and triple-helix-type networks. Furthermore, we consider triple-helix networks at three geographical scales: local, national and international. These relationships are tested on a random sample of 763 firms located in five urban regions of Norway which reported having introduced new products or services during the preceding 3 years. The analysis shows that firms exploiting internal hierarchy or triple-helix networks with a wide range of partners managed to derive a significantly higher share of their income from new products, compared to those that mainly relied on outsourcing within the market. In addition, the analysis shows that the geographical scale of cooperation in networks, as well as the type of partner used, matters for the capacity of firms to benefit from product innovation. In particular, firms that collaborate in international triple-helix-type networks involving suppliers, customers and R&D institutions extract a higher share of their income from product innovations, regardless of whether they organize the processes internally or through the network.

  16. Triple Bioaffinity Mass Spectrometry Concept for Thyroid Transporter Ligands

    NARCIS (Netherlands)

    Aqai, P.; Fryganas, C.; Mizuguchi, M.; Haasnoot, W.; Nielen, M.W.F.

    2012-01-01

    For the analysis of thyroid transporter ligands, a triple bioaffinity mass spectrometry (BioMS) concept was developed, with the aim at three different analytical objectives: rapid screening of any ligand, confirmation of known ligands in accordance with legislative requirements, and identification o

  17. The Triple Helix Model and the Knowledge-Based Economy

    NARCIS (Netherlands)

    Leydesdorff, L.; Meyer, M.

    2010-01-01

    The Triple Helix model of university-industry-government relations can be generalized from a neo-institutional model of networks of relations to a neo-evolutionary model of how three selection environments operate upon one another. Two selection mechanisms operating upon each other can mutually shap

  18. Hydration dynamics of the collagen triple helix by NMR.

    Science.gov (United States)

    Melacini, G; Bonvin, A M; Goodman, M; Boelens, R; Kaptein, R

    2000-07-28

    The hydration of the collagen-like Ac-(Gly-Pro-Hyp)(6)-NH(2) triple-helical peptide in solution was investigated using an integrated set of high-resolution NMR hydration experiments, including different recently developed exchange-network editing methods. This approach was designed to explore the hydration dynamics in the proximity of labile groups, such as the hydroxyproline hydroxyl group, and revealed that the first shell of hydration in collagen-like triple helices is kinetically labile with upper limits for water molecule residence times in the nanosecond to sub-nanosecond range. This result is consistent with a "hopping" hydration model in which solvent molecules are exchanged in and out of solvation sites at a rate that is not directly correlated to the degree of site localization. The hopping model thus reconciles the dynamic view of hydration revealed by NMR with the previously suggested partially ordered semi-clathrate-like cylinder of hydration. In addition, the nanosecond to sub-nanosecond upper limits for water molecule residence times imply that hydration-dehydration events are not likely to be the rate-limiting step for triple helix self-recognition, complementing previous investigations on water dynamics in collagen fibers. This study has also revealed labile proton features expected to facilitate the characterization of the structure and folding of triple helices in collagen peptides.

  19. Co-innovatie Triple P: integratie van marketingstrategie en personeelsbeleid

    NARCIS (Netherlands)

    Bartels, J.; Hendriks, R.; Ruyter, de P.; Zeelenberg, A.; Engelsman, V.; Eichelsheim, C.; Skoppek, H.; Schmidt, M.

    2008-01-01

    Dit project richt zicht op de integratie van Triple P marketing en personeelsbeleid. Het doel van het project luidt als volgt: “Hoe kun je in de marketing van biologische groenten en fruit effectief gebruik maken van de intrinsieke waarden van duurzame landbouw en maatschappelijk verantwoord onderne

  20. Ferritin heavy chain in triple negative breast cancer

    DEFF Research Database (Denmark)

    Liu, Ning Qing; De Marchi, Tommaso; Timmermans, Annemieke M

    2014-01-01

    Ferritin heavy chain (FTH1) is a 21-kDa subunit of the ferritin complex, known for its role in iron metabolism, and which has recently been identified as a favorable prognostic protein for triple negative breast cancer (TNBC) patients. Currently, it is not well understood how FTH1 contributes...

  1. Efficacy of Neoadjuvant Cisplatin in Triple-Negative Breast Cancer

    DEFF Research Database (Denmark)

    Szallasi, Zoltan Imre; Eklund, Aron Charles; Li, Qiyuan

    2010-01-01

    PURPOSE Cisplatin is a chemotherapeutic agent not used routinely for breast cancer treatment. As a DNA cross-linking agent, cisplatin may be effective treatment for hereditary BRCA1-mutated breast cancers. Because sporadic triple-negative breast cancer (TNBC) and BRCA1-associated breast cancer...

  2. A triple negative breast cancer: what it is not!

    Directory of Open Access Journals (Sweden)

    Katakkar SB

    2012-02-01

    Full Text Available Suresh B KatakkarRegional Medical Oncology Hematology Leader, Centre for the North, BC Cancer Agency, Prince George, British Columbia, CanadaAbstract: The triple negative cancer is an unusual, and at the same time, a unique entity where the discordance rate is almost 18%. That means 18% of Her2 negative results will transform into a Her2 positive status and will have the affinity to spread to the central nervous system (CNS. With the identification of CD44, CD24, and ALDH1, we may be able to determine which group of triple negative breast cancer patients will have CNS metastasis. This case illustrates the Her2 expressing cells have higher CNS affinity. As the original tumor was Her2 negative, if a genomic assay was then done on this patient, we would have identified the potential of CNS involvement. In conclusion, genomic assays should be routinely done on triple negative cancers.Keywords: triple negative, breast cancer, claudin high or low, genomic microassay

  3. Quadrupolar, Triple [Delta]-Function Potential in One Dimension

    Science.gov (United States)

    Patil, S. H.

    2009-01-01

    The energy and parity eigenstates for quadrupolar, triple [delta]-function potential are analysed. Using the analytical solutions in specific domains, simple expressions are obtained for even- and odd-parity bound-state energies. The Heisenberg uncertainty product is observed to have a minimum for a specific strength of the potential. The…

  4. Requirements of triple play services towards broadband access networks

    NARCIS (Netherlands)

    Wolfswinkel, R.N. van

    2005-01-01

    In the current broadband market there are many new developments regarding both services and the broadband infrastructures carrying those services. This paper will address what the requirements of services are towards broadband networks. The focus will be on the requirements of triple play related se

  5. Why are Hydrogen Bonds Directional?

    Indian Academy of Sciences (India)

    ABHISHEK SHAHI; ELANGANNAN ARUNAN

    2016-10-01

    The recent IUPAC recommendation on the definition of hydrogen bonding points out that directionality is a defining characteristic of a hydrogen bond and the angle ∠X-H-Y is generally linear or 180◦. It also suggests that the X-H· · ·Y angle be greater than 110◦ for an interaction to be characterized as a hydrogenbond but does not provide any rationale for the same. This article reports a rationale for limiting the angle, based on the electron density topology using the quantum theory of atoms in molecules. Electron density topology for common hydrogen bond donors HF, HCl, HBr, HNC, HCN and HCCH are reported in this work. These calculations lead to an interesting observation that the atomic basins of H atom in all these donor molecules are limited justifying the restriction of hydrogen bond angle. Moreover, similar analysis on some hydrogen bonded complexes confirms that beyond this angle the acceptor atom Y starts interacting with the atomic basin on X. However, conclusions based on bond lengths and angles have to be treated with care and as the IUPAC recommendation points out that independent ‘evidence for bond formation’ in every case is important.

  6. Physical Nature of Hydrogen Bond

    CERN Document Server

    Zhyganiuk, I V

    2015-01-01

    The physical nature and the correct definition of hydrogen bond (H-bond) are considered.\\,\\,The influence of H-bonds on the thermodynamic, kinetic, and spectroscopic properties of water is analyzed.\\,\\,The conventional model of H-bonds as sharply directed and saturated bridges between water molecules is incompatible with the behavior of the specific volume, evaporation heat, and self-diffusion and kinematic shear viscosity coefficients of water. On the other hand, it is shown that the variation of the dipole moment of a water molecule and the frequency shift of valence vibrations of a hydroxyl group can be totally explained in the framework of the electrostatic model of H-bond.\\,\\,At the same time, the temperature dependences of the heat capacity of water in the liquid and vapor states clearly testify to the existence of weak H-bonds.\\,\\,The analysis of a water dimer shows that the contribution of weak H-bonds to its ground state energy is approximately 4--5 times lower in comparison with the energy of electr...

  7. Spinal cord atrophy in triple A syndrome associated with a novel compound heterozygous mutation.

    Science.gov (United States)

    Kunte, Hagen; Trendelenburg, George; Matzen, Julia; Ventz, Manfred; Kornak, Uwe; Harms, Lutz

    2010-01-01

    A 38-year-old male patient was admitted with slowly progressive spastic gait disturbance. Imaging revealed general spinal cord atrophy. Because of adrenal insufficiency, alacrima and achalasia, triple A syndrome was suspected. This is a case report of a triple A syndrome patient with a predominance of neurological features and a new heterozygous compound mutation in triple A syndrome gene.

  8. The chemisorptive bond basic concepts

    CERN Document Server

    Clark, Alfred

    1974-01-01

    The Chemisorptive Bond: Basic Concepts describes the basic concepts of the chemisorptive bond on solid surfaces from the simple analogies with ordinary chemical bonds to the quantum-mechanical approaches.This book is composed of 10 chapters and begins with discussions of simple formulas for correlating measurable quantities in chemisorptions and catalysis. The succeeding chapters deal with theories based on quantum-mechanical principles that describe the mutual interactions of atoms of the solid and foreign atoms on the surface. The remaining chapters consider the possible arrangements

  9. PRICING OF MULTIPLE DEFAULTABLE BOND

    Institute of Scientific and Technical Information of China (English)

    JianZhihong; LiChulin

    2002-01-01

    In this paper a generalized defaultable bond pricing formula is derived by assuming that there exists a defaultable forward rate term structure and that firms in the economy interact when default occurs. Generally,The risk-neutral default intensity χQ is not equal to the empirical or actual default intensity λ,. This paper proves that multiple default intensities are invari-ant under equivalent martingale transformation,given a well-diversified portfolio corresponding to the defaultable bond. Thus one can directly apply default intensities and fractional losses empirically estimated to the evaluation of defaultable bonds or contingent claims.

  10. Direct Bonded Pontic (Laporan Kasus

    Directory of Open Access Journals (Sweden)

    Suhandi Sidjaja

    2015-10-01

    Full Text Available Advanced science and technology in dentistry enable dental practitioners to modified she bonding techniques in tooth replacement. A pontic made of composite resin bonded to etched enamel of the adjacent teeth can be used in the replacement of one missing anterior tooth with a virgin or sowed adpicent tooth. The advantages of this technique include a one visit treatment, cow cost, good esthetics, less side effects and easy repair or rebounding. Clinical evaluation showed a high success rate therefore with a proper diagnosis and a perfect skill of the direct bonded technique this treatment can be used as an alternative restoration.

  11. Roll bonding of strained aluminium

    DEFF Research Database (Denmark)

    Staun, Jakob M.

    2003-01-01

    This report investigates roll bonding of pre-strained (å ~ 4) aluminium sheets to produce high strain material from high purity aluminium (99.996%) and commercial pure aluminium (99.6%). The degree of bonding is investigated by optical microscopy and ultrasonic scanning. Under the right...... of the cross rolled volume fraction is found. To further asses this effect, and the anisotropy, it is necessary to acquire knowledge about both texture and microstructure, e.g. by TEM. Roll bonding of pre-strained aluminium is found to be a possible alternative to ARB in the quest for ultra-fine grained...

  12. Integration of European Bond Markets

    DEFF Research Database (Denmark)

    Christiansen, Charlotte

    2014-01-01

    I investigate the time variation in the integration of EU government bond markets. The integration is measured by the explanatory power of European factor portfolios for the individual bond markets for each year. The integration of the government bond markets is stronger for EMU than non-EMU memb......-EMU members and stronger for old than new EU members. For EMU countries, the integration is weaker the lower the credit rating is. During the recent crisis periods, the integration is weaker, particularly for EMU countries....

  13. Combinatorics of RNA Secondary Structures with Base Triples.

    Science.gov (United States)

    Müller, Robert; Nebel, Markus E

    2015-07-01

    The structure of RNA has been the subject of intense research over the last decades due to its importance for the correct functioning of RNA molecules in biological processes. Hence, a large number of models for RNA folding and corresponding algorithms for structure prediction have been developed. However, previous models often only consider base pairs, although every base is capable of up to three edge-to-edge interactions with other bases. Recently, Höner zu Siederdissen et al. presented an extended model of RNA secondary structure, including base triples together with a folding algorithm-the first thermodynamics-based algorithm that allows the prediction of secondary structures with base triples. In this article, we investigate the search space processed by this new algorithm, that is, the combinatorics of extended RNA secondary structures with base triples. We present generalized definitions for structural motifs like hairpins, stems, bulges, or interior loops occurring in structures with base triples. Furthermore, we prove precise asymptotic results for the number of different structures (size of search space) and expectations for various parameters associated with structural motifs (typical shape of folding). Our analysis shows that the asymptotic number of secondary structures of size n increases exponentially to [Formula: see text] compared to the classic model by Stein and Waterman for which [Formula: see text] structures exist. A comparison with the classic model reveals large deviations in the expected structural appearance, too. The inclusion of base triples constitutes a significant refinement of the combinatorial model of RNA secondary structure, which, by our findings, is quantitatively characterized. Our results are of special theoretical interest, because a closer look at the numbers involved suggests that extended RNA secondary structures constitute a new combinatorial class not bijective with any other combinatorial objects studied so far.

  14. mTOR in breast cancer: differential expression in triple-negative and non-triple-negative tumors.

    LENUS (Irish Health Repository)

    Walsh, S

    2012-04-01

    Triple-negative breast cancer (TNBC) is defined by the absence of estrogen receptors (ER), progesterone receptors (PR) and overexpression of HER2. Targeted therapy is currently unavailable for this subgroup of breast cancer patients. mTOR controls cancer cell growth, survival and invasion and is thus a potential target for the treatment of patients with TNBC. Using immunohistochemistry, mTOR and p-mTOR were measured in 89 TNBCs and 99 non-TNBCs. While mTOR expression was confined to tumor cell cytoplasm, p-mTOR staining was located in the nucleus, perinuclear area and in the cytoplasm. Potentially important, was our finding that nuclear p-mTOR was found more frequently in triple-negative than non triple-negative cancers (p < 0.001). These results suggest that mTOR may play a more important role in the progression of TNBC compared to non-TNBC. Based on these findings, we conclude that mTOR may be a new target for the treatment of triple-negative breast cancer.

  15. Technetium dichloride: a new binary halide containing metal-metal multiple bonds.

    Science.gov (United States)

    Poineau, Frederic; Malliakas, Christos D; Weck, Philippe F; Scott, Brian L; Johnstone, Erik V; Forster, Paul M; Kim, Eunja; Kanatzidis, Mercouri G; Czerwinski, Kenneth R; Sattelberger, Alfred P

    2011-06-15

    Technetium dichloride has been discovered. It was synthesized from the elements and characterized by several physical techniques, including single crystal X-ray diffraction. In the solid state, technetium dichloride exhibits a new structure type consisting of infinite chains of face sharing [Tc(2)Cl(8)] rectangular prisms that are packed in a commensurate supercell. The metal-metal separation in the prisms is 2.127(2) Å, a distance consistent with the presence of a Tc≡Tc triple bond that is also supported by electronic structure calculations.

  16. 27 CFR 19.245 - Bonds and penal sums of bonds.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Bonds and penal sums of... Bonds and penal sums of bonds. The bonds, and the penal sums thereof, required by this subpart, are as follows: Penal Sum Type of bond Basis Minimum Maximum (a) Operations bond: (1) One plant bond—...

  17. Prevalence of Germline Mutations in Genes Engaged in DNA Damage Repair by Homologous Recombination in Patients with Triple-Negative and Hereditary Non-Triple-Negative Breast Cancers.

    Directory of Open Access Journals (Sweden)

    Pawel Domagala

    Full Text Available This study sought to assess the prevalence of common germline mutations in several genes engaged in the repair of DNA double-strand break by homologous recombination in patients with triple-negative breast cancers and hereditary non-triple-negative breast cancers. Tumors deficient in this type of DNA damage repair are known to be especially sensitive to DNA cross-linking agents (e.g., platinum drugs and to poly(ADP-ribose polymerase (PARP inhibitors.Genetic testing was performed for 36 common germline mutations in genes engaged in the repair of DNA by homologous recombination, i.e., BRCA1, BRCA2, CHEK2, NBN, ATM, PALB2, BARD1, and RAD51D, in 202 consecutive patients with triple-negative breast cancers and hereditary non-triple-negative breast cancers.Thirty five (22.2% of 158 patients in the triple-negative group carried mutations in genes involved in DNA repair by homologous recombination, while 10 (22.7% of the 44 patients in the hereditary non-triple-negative group carried such mutations. Mutations in BRCA1 were most frequent in patients with triple-negative breast cancer (18.4%, and mutations in CHEK2 were most frequent in patients with hereditary non-triple-negative breast cancers (15.9%. In addition, in the triple-negative group, mutations in CHEK2, NBN, and ATM (3.8% combined were found, while mutations in BRCA1, NBN, and PALB2 (6.8% combined were identified in the hereditary non-triple-negative group.Identifying mutations in genes engaged in DNA damage repair by homologous recombination other than BRCA1/2 can substantially increase the proportion of patients with triple-negative breast cancer and hereditary non-triple-negative breast cancer who may be eligible for therapy using PARP inhibitors and platinum drugs.

  18. 27 CFR 25.94 - Strengthening bonds.

    Science.gov (United States)

    2010-04-01

    ...) Requirement. When the penal sum of the brewer's bond (calculated as provided in § 25.93) in effect is not... strengthening bond in sufficient penal sum if the surety is the same as on the bond in effect. If the surety is... bond may not in any way release a former bond or limit a bond to less than the full penal sum. (c)...

  19. Weld bonding of stainless steel

    DEFF Research Database (Denmark)

    Santos, I. O.; Zhang, Wenqi; Goncalves, V.M.

    2004-01-01

    This paper presents a comprehensive theoretical and experimental investigation of the weld bonding process with the purpose of evaluating its relative performance in case of joining stainless steel parts, against alternative solutions based on structural adhesives or conventional spot...

  20. Hydrogen bonding in tight environments

    DEFF Research Database (Denmark)

    Pirrotta, Alessandro; Solomon, Gemma C.; Franco, Ignacio

    2016-01-01

    The single-molecule force spectroscopy of a prototypical class of hydrogen-bonded complexes is computationally investigated. The complexes consist of derivatives of a barbituric acid and a Hamilton receptor that can form up to six simultaneous hydrogen bonds. The force-extension (F-L) isotherms...... of the host-guest complexes are simulated using classical molecular dynamics and the MM3 force field, for which a refined set of hydrogen bond parameters was developed from MP2 ab initio computations. The F-L curves exhibit peaks that signal conformational changes during elongation, the most prominent...... of which is in the 60-180 pN range and corresponds to the force required to break the hydrogen bonds. These peaks in the F-L curves are shown to be sensitive to relatively small changes in the chemical structure of the host molecule. Thermodynamic insights into the supramolecular assembly were obtained...

  1. Modified bonded bridge space maintainer.

    Science.gov (United States)

    Liegeois, F; Limme, M

    1999-01-01

    The premature loss of primary teeth can create the need for space maintenance and restoration of function. This article presents a fixed bonded space maintainer, which allows space to be maintained with economy of dental tissues.

  2. Adhesives for orthodontic bracket bonding

    Directory of Open Access Journals (Sweden)

    Déborah Daniella Diniz Fonseca

    2010-04-01

    Full Text Available The advent of acid etching, introduced by Buonocore in 1955, brought the possibility of bonding between the bracket base and enamel, contributing to more esthetic and conservative orthodontics. This direct bracket bonding technique has brought benefits such as reduced cost and time in performing the treatment, as well as making it easier to perform oral hygiene. The aim of this study was to conduct a survey of published studies on orthodontic bracket bonding to dental enamel. It was verified that resin composites and glass ionomer are the most studied and researched materials for this purpose. Resin-modified glass ionomer, with its biocompatibility, capacity of releasing fluoride and no need for acid etching on the tooth structure, has become increasingly popular among dentists. However, due to the esthetic and mechanical properties of light polymerizable resin composite, it continues to be one of the adhesives of choice in the bracket bonding technique and its use is widely disseminated.

  3. Study of bis(bibenzyls) in bryophytes using electron ionization time-of-flight and electrospray ionization triple-quadrupole mass spectrometry.

    Science.gov (United States)

    Guo, Huaifang; Xing, Jie; Xie, Chunfeng; Qu, Jianbo; Gao, Yanhui; Lou, Hongxiang

    2007-01-01

    A detailed analysis of mass spectra generated from bis(bibenzyl) compounds in bryophytes under electron ionization time-of-flight (EI-TOF) and electrospray ionization triple-quadrupole (ESI-TQ) mass spectrometry conditions is reported. Proposed structures of the fragment ions were obtained by tracking the functional groups of 15 bis(bibenzyls), the structures of which are similar except for some alkoxyl substituents and linkage sites of biphenyl ether bonds. The elucidation was aided by the use of accurate mass measurements. Attempts have been made to provide rational pathways for the formation of these fragment ions, and a generalized fragmentation mechanism is proposed. The bis(bibenzyls) mentioned in this study include three types according to their structure characteristics, i.e. one biphenyl ether bond (A-type), two biphenyl ether bonds (B-type), one biphenyl ether and one biphenyl bond (C-type). The three types display different EI-MS and ESI-MS/MS product profiles, by which the bis(bibenzyl) type and the number of alkoxyl substituents can be identified. Isomers of bis(bibenzyls) can be differentiated to some extent, while the linkage sites of biphenyl ether bonds are difficult to identify. The structure-fragmentation relationships will facilitate the characterization of other bis(bibenzyls) and this will be of value for the high-throughput screening of novel bis(bibenzyls) in bryophytes.

  4. Dynamical formation & scattering of hierarchical triples: Cross sections, Kozai-Lidov oscillations, and collisions

    CERN Document Server

    Antognini, Joseph M O

    2015-01-01

    Dynamical scattering of binaries and triple systems of stars, planets, and compact objects may produce highly inclined triple systems subject to Kozai-Lidov (KL) oscillations, potentially leading to collisions, mergers, Type Ia supernovae, and other phenomena. We present the results of more than 400 million gravitational scattering experiments of binary-binary, triple-single, and triple-binary scattering. We compute the cross sections for all possible outcomes and explore their dependencies on incoming velocity, mass, semi-major axis, and eccentricity, including analytic fits and discussion of the velocity dependence. For the production of new triple systems by scattering we find that compact triples are preferred, with ratios of outer to inner semi-major axes of ~few--100, flat or quasi-thermal eccentricity distributions, and flat distributions in cosine of the mutual inclination. Dynamically formed triples are thus subject to strong KL oscillations, the "eccentric Kozai mechanism," and non-secular effects. ...

  5. LAMMPS Framework for Directional Dynamic Bonding

    DEFF Research Database (Denmark)

    2012-01-01

    and bond types. When breaking bonds, all angular and dihedral interactions involving broken bonds are removed. The framework allows chemical reactions to be modeled, and use it to simulate a simplistic, coarse-grained DNA model. The resulting DNA dynamics illustrates the power of the present framework.......We have extended the Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) to support directional bonds and dynamic bonding. The framework supports stochastic formation of new bonds, breakage of existing bonds, and conversion between bond types. Bond formation can be controlled...... to limit the maximal functionality of a bead with respect to various bond types. Concomitant with the bond dynamics, angular and dihedral interactions are dynamically introduced between newly connected triplets and quartets of beads, where the interaction type is determined from the local pattern of bead...

  6. An investigation of hydrogen bonding between HCl and vinylacetylene: A molecule with two different π-acceptor sites

    Science.gov (United States)

    Kisiel, Z.; Fowler, P. W.; Legon, A. C.; Devanne, D.; Dixneuf, P.

    1990-11-01

    The ground state rotational spectrum of a hydrogen-bonded dimer formed by vinylacetylene and hydrogen chloride has been detected by the pulsed-nozzle, Fourier-transform microwave technique. Vinylacetylene has been chosen as a prototype acceptor molecule containing two different π-acceptor sites. Rotational constants A0, B0, C0, centrifugal distortion constants ΔJ, ΔJK, δJ, δK, and three components χaa, χbb-χcc, and χab of the Cl nuclear quadrupole coupling tensor have been determined for each of the three isotopomers CH2CHCCHṡṡṡ H35Cl, CH2CHCCHṡṡṡH37Cl, and CH2CHCCHṡṡṡD35Cl. These spectroscopic constants have been interpreted in terms of a dimer in which the HCl subunit forms a hydrogen bond to the C 3/4 C triple bond in a T-shape configuration, but is displaced from the center of the triple bond by d=0.04 Å towards the inner C atom, and makes an angle φ=34° with the vinylacetylene plane. The experimental angular geometry is in excellent agreement with that predicted by the Buckingham-Fowler electrostatic model which gives φ=27°.

  7. Transient hydrogen bonding in uniformly ¹³C,¹⁵N-labeled carbohydrates in water.

    Science.gov (United States)

    Norris, Scott E; Landström, Jens; Weintraub, Andrej; Bull, Thomas E; Widmalm, Göran; Freedberg, Darón I

    2012-03-01

    We report NMR studies of transient hydrogen bonding in a polysaccharide (PS) dissolved in water without cosolvent at ambient temperature. The PS portion of the Escherichia coli O142 lipopolysaccharide is comprised of repeating pentasaccharide units of GalNAc (N-acetyl galactosamine), GlcNAc (N-acetyl glucosamine), and rhamnose in a 3:1:1 ratio, respectively. A 105-ns molecular dynamics (MD) simulation on one pentasaccharide repeat unit predicts transient inter-residue hydrogen bonds from the GalNAc NH groups in the PS. To investigate these predictions experimentally, the PS was uniformly ¹³C,¹⁵N enriched and the NH, carbonyl, C2, C4, and methyl resonances of the GalNAc and GlcNAc residues assigned using through-bond triple-resonance NMR experiments. Temperature dependence of amide NH chemical shifts and one-bond NH J couplings support that NH groups on two of the GalNAc residues are donors in transient hydrogen bonds. The remaining GalNAc and GlcNAc NHs do not appear to be donors from either temperature-dependent chemical shifts or one-bond NH J couplings. These results substantiate the presence of weak or partial hydrogen bonds in carbohydrates, and that MD simulations of repeating units in PSs provide insight into overall PS structure and dynamics.

  8. Bonding and impedance matching of acoustic transducers using silver epoxy.

    Science.gov (United States)

    Son, Kyu Tak; Lee, Chin C

    2012-04-01

    Silver epoxy was selected to bond transducer plates on glass substrates. The properties and thickness of the bonding medium affect the electrical input impedance of the transducer. Thus, the thickness of the silver epoxy bonding layer was used as a design parameter to optimize the structure for the transducer input impedance to match the 50 Ω output impedance of most radio frequency (RF) generators. Simulation and experimental results show that nearly perfect matching is achieved without using any matching circuit. At the matching condition, the transducer operates at a frequency band a little bit below the half-wavelength resonant frequency of the piezoelectric plate. In experiments, lead titanate (PT) piezoelectric plates were employed. Both full-size, 11.5 mm × 2 mm × 0.4 mm, and half-size, 5.75 mm × 2 mm × 0.4 mm, can be well matched using optimal silver epoxy thickness. The transducer assemblies demonstrate high efficiency. The conversion loss from electrical power to acoustic power in soda-lime glass is 4.3 dB. This loss is low considering the fact that the transducers operate at off-resonance by 12%. With proper choice of silver epoxy thickness, the transducer can be matched at the fundamental, the 3rd and 5th harmonic frequencies. This leads to the possible realization of triple-band transducers. Reliability was assessed with thermal cycling test according to Telcordia GR-468-Core recommendation. Of the 30 transducer assemblies tested, none broke until 2900 cycles and 27 have sustained beyond 4050 cycles.

  9. Prognostic significance of Bcl-2 in invasive mammary carcinomas: a comparative clinicopathologic study between "triple-negative" and non-"triple-negative" tumors.

    Science.gov (United States)

    Tawfik, Kareem; Kimler, Bruce F; Davis, Marilyn K; Fan, Fang; Tawfik, Ossama

    2012-01-01

    Bcl-2 is a tumorigenic protein that is expressed in 25% to 50% of breast cancers. Although its expression has been widely accepted as a favorable prognostic marker, its protective mechanism of action remains unclear. "Triple-negative" tumors are an aggressive subgroup known to carry a poor prognosis. Studies documenting prognostic significance of Bcl-2 expression in triple-negative in comparison to non-triple-negative breast cancers are limited. Bcl-2 expression was correlated with tumor size, grade, histologic type, lymphovascular invasion, lymph node status, patients' overall survival, estrogen receptor, progesterone receptor, Her-2, p53, and epidermal growth factor receptor in 124 triple-negative and 458 non-triple-negative tumors. There were significant differences between triple-negative and non-triple-negative tumors in their relationship to Bcl-2 expression (81% versus 29%, respectively) and tumor aggression. As previously reported, in non-triple-negative tumors, Bcl-2 positivity correlated with less aggressive tumors (94% of grade I tumors were Bcl-2+ versus 62% of grade III tumors, P < .011) and overall survival (P = .008). However, the opposite was true in patients with triple-negative tumors, where Bcl-2 positivity was associated with poorer survival (P = .64). In triple-negative tumors, Bcl-2 positivity was not associated with any of the aforementioned parameters except for a lower incidence of lymph node metastasis. Moreover, by Cox regression analysis of all variables, in patients with triple-negative tumors, lymphovascular invasion (P = .009) and Bcl-2 expression (P = .028) were predictors of poor survival. In conclusion, there are major clinicopathologic differences between breast cancer phenotypes. Our results establish the value of using Bcl-2 in prognostic stratification of patients and its potential therapeutic implications in selecting patients for treatment.

  10. Halogen bonds in crystal engineering: like hydrogen bonds yet different.

    Science.gov (United States)

    Mukherjee, Arijit; Tothadi, Srinu; Desiraju, Gautam R

    2014-08-19

    The halogen bond is an attractive interaction in which an electrophilic halogen atom approaches a negatively polarized species. Short halogen atom contacts in crystals have been known for around 50 years. Such contacts are found in two varieties: type I, which is symmetrical, and type II, which is bent. Both are influenced by geometric and chemical considerations. Our research group has been using halogen atom interactions as design elements in crystal engineering, for nearly 30 years. These interactions include halogen···halogen interactions (X···X) and halogen···heteroatom interactions (X···B). Many X···X and almost all X···B contacts can be classified as halogen bonds. In this Account, we illustrate examples of crystal engineering where one can build up from previous knowledge with a focus that is provided by the modern definition of the halogen bond. We also comment on the similarities and differences between halogen bonds and hydrogen bonds. These interactions are similar because the protagonist atoms-halogen and hydrogen-are both electrophilic in nature. The interactions are distinctive because the size of a halogen atom is of consequence when compared with the atomic sizes of, for example, C, N, and O, unlike that of a hydrogen atom. Conclusions may be drawn pertaining to the nature of X···X interactions from the Cambridge Structural Database (CSD). There is a clear geometric and chemical distinction between type I and type II, with only type II being halogen bonds. Cl/Br isostructurality is explained based on a geometric model. In parallel, experimental studies on 3,4-dichlorophenol and its congeners shed light on the nature of halogen···halogen interactions and reveal the chemical difference between Cl and Br. Variable temperature studies also show differences between type I and type II contacts. In terms of crystal design, halogen bonds offer a unique opportunity in the strength, atom size and interaction gradation; this may be

  11. Property Graph vs RDF Triple Store: A Comparison on Glycan Substructure Search.

    Directory of Open Access Journals (Sweden)

    Davide Alocci

    Full Text Available Resource description framework (RDF and Property Graph databases are emerging technologies that are used for storing graph-structured data. We compare these technologies through a molecular biology use case: glycan substructure search. Glycans are branched tree-like molecules composed of building blocks linked together by chemical bonds. The molecular structure of a glycan can be encoded into a direct acyclic graph where each node represents a building block and each edge serves as a chemical linkage between two building blocks. In this context, Graph databases are possible software solutions for storing glycan structures and Graph query languages, such as SPARQL and Cypher, can be used to perform a substructure search. Glycan substructure searching is an important feature for querying structure and experimental glycan databases and retrieving biologically meaningful data. This applies for example to identifying a region of the glycan recognised by a glycan binding protein (GBP. In this study, 19,404 glycan structures were selected from GlycomeDB (www.glycome-db.org and modelled for being stored into a RDF triple store and a Property Graph. We then performed two different sets of searches and compared the query response times and the results from both technologies to assess performance and accuracy. The two implementations produced the same results, but interestingly we noted a difference in the query response times. Qualitative measures such as portability were also used to define further criteria for choosing the technology adapted to solving glycan substructure search and other comparable issues.

  12. Aptamer/target binding-induced triple helix forming for signal-on electrochemical biosensing.

    Science.gov (United States)

    Mao, Yinfei; Liu, Jinquan; He, Dinggen; He, Xiaoxiao; Wang, Kemin; Shi, Hui; Wen, Li

    2015-10-01

    Owing to its diversified structures, high affinity, and specificity for binding a wide range of non-nucleic acid targets, aptamer is a useful molecular recognition tool for the design of various biosensors. Herein, we report a new signal-on electrochemical biosensing platform which is based on an aptamer/target binding-induced strand displacement and triple-helix forming. The biosensing platform is composed of a signal transduction probe (STP) modified with a methylene blue (MB) and a sulfhydryl group, a triplex-forming oligonucleotides probe (TFO) and a target specific aptamer probe (Apt). Through hybridization with the TFO probe and the Apt probe, the self-assembled STP on Au electrode via Au-S bonding keeps its rigid structure. The MB on the STP is distal to the Au electrode surface. It is eT off state. Target binding releases the Apt probe and liberates the end of the MB tagged STP to fold back and form a triplex-helix structure with TFO (STP/TFO/STP), allowing MB to approach the Au electrode surface and generating measurable electrochemical signals (eT ON). As test for the feasibility and universality of this signal-on electrochemical biosensing platform, two aptamers which bind to adenosine triphosphate (ATP) and human α-thrombin (Tmb), respectively, are selected as models. The detection limit of ATP was 7.2 nM, whereas the detection limit of Tmb was 0.86 nM.

  13. Comparative NMR analysis of collagen triple helix organization from N- to C-termini.

    Science.gov (United States)

    Acevedo-Jake, Amanda M; Jalan, Abhishek A; Hartgerink, Jeffrey D

    2015-01-12

    The collagen triple helix consists of three supercoiled solvent-exposed polypeptide chains, and by dry weight it is the most abundant fold in mammalian tissues. Many factors affecting the structure and stability of collagen have been determined through the use of short synthetically prepared peptides, generally called collagen-mimetic peptides (CMPs). NMR (nuclear magnetic resonance spectroscopy) investigations into the molecular structure of CMPs have suffered from large amounts of signal overlap and degeneracy because of collagen's repetitive primary sequence, the close and symmetric packing of the three chains and the identical peptide sequences found in homotrimers. In this paper a peptide library is prepared in which a single isotopic (15)N-Gly label is moved sequentially along the peptide backbone. Our approach allows for a more explicit examination of local topology than available in past reports. This reveals larger regions of disorder at the C-terminus than previously detected by crystallographic or NMR studies, and here C-terminal fraying is seen to extend for six amino acids in a (POG)10 sequence. Furthermore, small sequence changes at the N-terminus greatly influence the degree of this localized disorder and may be useful in the future design of CMPs to maximize collagen's interstrand hydrogen bonding pattern. Our approach and data serves as a reference for future CMP characterizations to determine the quality and extent of folding.

  14. Property Graph vs RDF Triple Store: A Comparison on Glycan Substructure Search.

    Science.gov (United States)

    Alocci, Davide; Mariethoz, Julien; Horlacher, Oliver; Bolleman, Jerven T; Campbell, Matthew P; Lisacek, Frederique

    2015-01-01

    Resource description framework (RDF) and Property Graph databases are emerging technologies that are used for storing graph-structured data. We compare these technologies through a molecular biology use case: glycan substructure search. Glycans are branched tree-like molecules composed of building blocks linked together by chemical bonds. The molecular structure of a glycan can be encoded into a direct acyclic graph where each node represents a building block and each edge serves as a chemical linkage between two building blocks. In this context, Graph databases are possible software solutions for storing glycan structures and Graph query languages, such as SPARQL and Cypher, can be used to perform a substructure search. Glycan substructure searching is an important feature for querying structure and experimental glycan databases and retrieving biologically meaningful data. This applies for example to identifying a region of the glycan recognised by a glycan binding protein (GBP). In this study, 19,404 glycan structures were selected from GlycomeDB (www.glycome-db.org) and modelled for being stored into a RDF triple store and a Property Graph. We then performed two different sets of searches and compared the query response times and the results from both technologies to assess performance and accuracy. The two implementations produced the same results, but interestingly we noted a difference in the query response times. Qualitative measures such as portability were also used to define further criteria for choosing the technology adapted to solving glycan substructure search and other comparable issues.

  15. Theoretical study of NMR, infrared and Raman spectra on triple-decker phthalocyanines

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Atsushi; Oku, Takeo [Department of Materials Science, The University of Shiga Prefecture 2500 Hassaka, Hikone, Shiga, 522-8533 (Japan)

    2016-02-01

    Electronic structures and magnetic properties of multi-decker phthalocyanines were studied by theoretical calculation. Electronic structures, excited processes at multi-states, isotropic chemical shifts of {sup 13}C, {sup 14}N and {sup 1}H-nuclear magnetic resonance (NMR), principle V-tensor in electronic field gradient (EFG) tensor and asymmetry parameters (η), vibration mode in infrared (IR) and Raman spectra of triple-decker phthalocyanines were calculated by density functional theory (DFT) and time-dependent DFT using B3LYP as basis function. Electron density distribution was delocalized on the phthalocyanine rings with electron static potential. Considerable separation of chemical shifts in {sup 13}C, {sup 14}N and {sup 1}H-NMR was originated from nuclear spin interaction between nitrogen and carbon atoms, nuclear quadrupole interaction based on EFG and η of central metal under crystal field. Calculated optical absorption at multi-excited process was derived from overlapping π-orbital on the phthalocyanine rings. The vibration modes in IR and Raman spectra were based on in-plane deformation and stretching vibrations of metal-ligand coordination bond on the deformed structure.

  16. Arctigenin inhibits STAT3 and exhibits anticancer potential in human triple-negative breast cancer therapy

    Science.gov (United States)

    Shen, Wanxiang; Zhang, Liang; Gu, Xinsheng; Guo, Yang; Tsai, Hsiang-i; Liu, Xuewen; Li, Jian; Zhang, Jingxuan; Li, Shan; Wu, Fuyun; Liu, Ying

    2017-01-01

    Triple-negative breast cancers (TNBCs) are the most aggressive and hard-to-treat breast tumors with poor prognosis, and exploration for novel therapeutic drugs is impending. Arctigenin (Atn), a bioactive lignan isolated from seeds of Arctium lappa L, has been reported to inhibit many cancer types; however, the effect of Atn on TNBC remains unclear. In this study, we demonstrated that Atn decreased proliferation, and induced apoptosis in TNBC cells. Furthermore, we explored the underlying mechanism of Atn inhibition on TNBC cells. Computational docking and affinity assay showed that Atn bound to the SH2 domain of STAT3. Atn inhibited STAT3 binding to genomic DNA by disrupting hydrogen bond linking between DNA and STAT3. In addition, Atn augmented Taxotere®-induced TNBC cell cytotoxicity. TNBC xenograft tests also confirmed the antitumor effect of Atn in vivo. These characteristics render Atn as a promising candidate drug for further development and for designing new effective STAT3 inhibitors. PMID:27861147

  17. Measurement of the quadratic hyperpolarizability of the collagen triple helix and application to second harmonic imaging of natural and biomimetic collagenous tissues

    Science.gov (United States)

    Deniset-Besseau, A.; Strupler, M.; Duboisset, J.; De Sa Peixoto, P.; Benichou, E.; Fligny, C.; Tharaux, P.-L.; Mosser, G.; Brevet, P.-F.; Schanne-Klein, M.-C.

    2009-09-01

    Collagen is a major protein of the extracellular matrix that is characterized by triple helical domains. It plays a central role in the formation of fibrillar and microfibrillar networks, basement membranes, as well as other structures of the connective tissue. Remarkably, fibrillar collagen exhibits efficient Second Harmonic Generation (SHG) so that SHG microscopy proved to be a sensitive tool to probe the three-dimensional architecture of fibrillar collagen and to assess the progression of fibrotic pathologies. We obtained sensitive and reproducible measurements of the fibrosis extent, but we needed quantitative data at the molecular level to further process SHG images. We therefore performed Hyper- Rayleigh Scattering (HRS) experiments and measured a second order hyperpolarisability of 1.25 10-27 esu for rat-tail type I collagen. This value is surprisingly large considering that collagen presents no strong harmonophore in its aminoacid sequence. In order to get insight into the physical origin of this nonlinear process, we performed HRS measurements after denaturation of the collagen triple helix and for a collagen-like short model peptide [(Pro-Pro- Gly)10]3. It showed that the collagen large nonlinear response originates in the tight alignment of a large number of weakly efficient harmonophores, presumably the peptide bonds, resulting in a coherent amplification of the nonlinear signal along the triple helix. To illustrate this mechanism, we successfully recorded SHG images in collagenous biomimetic matrices.

  18. Role of carbohydrate in stabilizing the triple-helix in a model for a deep-sea hydrothermal vent worm collagen.

    Science.gov (United States)

    Bann, James G; Bächinger, Hans Peter; Peyton, David H

    2003-04-15

    The glycopeptide Ac-(Gly-Pro-Thr(beta-Gal))(10)-NH(2) forms a collagen-like triple-helix. A (1)H NMR structural analysis is reported for the peptides Ac-(Gly-Pro-Thr)(n)-NH(2) and Ac-(Gly-Pro-Thr(beta-Gal))(n)-NH(2), where n = 1, 5, and 10. NMR assignments for the individual peptides are made using one- and two-dimensional TOCSY, ROESY, and NOESY experiments. The NMR and corroborating CD data show that Ac-(Gly-Pro-Thr)(n)-NH(2), n = 1, 5, or 10, as well as Ac-(Gly-Pro-Thr(beta-Gal))(n)-NH(2), n = 1 or 5 peptides are unable to form collagen-like triple-helical structures. Furthermore, the equilibrium ratio of cis to trans isomers of the Pro residues is unaffected by the presence of carbohydrate. For Ac-(Gly-Pro-Thr(beta-Gal))(10)-NH(2), the kinetics of amide (1)H exchange with solvent deuterium indicate a slow rate of exchange for both the Gly and the Thr amide. The data are thus consistent with a model in which the carbohydrate stabilizes the triple helix through an occlusion of water molecules and by hydrogen bonding but not through an influence on the cis to trans isomer ratio.

  19. Viscous solution of the triple shock reflection problem

    CERN Document Server

    Lau-Chapdelaine, S She-Ming

    2016-01-01

    The reflection of a triple-shock configuration was studied numerically in two dimensions using the Navier-Stokes equations. The flow field was initialized using three shock theory, and the reflection of the triple point on a plane of symmetry was studied. The conditions simulated a stoichiometric methane-oxygen detonation cell at low pressure on time scales preceding ignition, when the gas was assumed to be thermodynamically inert. Viscosity was found to play an important role on some shock reflection mechanisms believed to accelerate reaction rates in detonations where time scales are small. A small wall jet was present in the double Mach reflection and increased in size with Reynolds number, eventually forming a small vortex. Kelvin-Helmholtz instabilities were absent and there was no Mach stem bifurcation at Reynolds numbers corresponding to and exceeding the induction length. Kelvin-Helmholtz instabilities are unlikely to be a source of rapid reactions in detonations at time scales commensurate with the i...

  20. Triple Helix Formation in a Topologically Controlled DNA Nanosystem.

    Science.gov (United States)

    Yamagata, Yutaro; Emura, Tomoko; Hidaka, Kumi; Sugiyama, Hiroshi; Endo, Masayuki

    2016-04-11

    In the present study, we demonstrate single-molecule imaging of triple helix formation in DNA nanostructures. The binding of the single-molecule third strand to double-stranded DNA in a DNA origami frame was examined using two different types of triplet base pairs. The target DNA strand and the third strand were incorporated into the DNA frame, and the binding of the third strand was controlled by the formation of Watson-Crick base pairing. Triple helix formation was monitored by observing the structural changes in the incorporated DNA strands. It was also examined using a photocaged third strand wherein the binding of the third strand was directly observed using high-speed atomic force microscopy during photoirradiation. We found that the binding of the third strand could be controlled by regulating duplex formation and the uncaging of the photocaged strands in the designed nanospace.

  1. Assembly of Liposomes Controlled by Triple Helix Formation

    DEFF Research Database (Denmark)

    Vogel, Stefan; Jakobsen, Ulla

    2013-01-01

    -covalent immobilization of oligonucleotides on the surface of soft nanoparticles (e.g. liposomes) and the subsequent controlled assembly by DNA triple helix formation. The non-covalent approach avoids tedious surface chemistry and necessary purification procedures and can simplify and extend the available methodology......Attachment of DNA to the surface of different solid nanoparticles (e.g. gold- and silica nanoparticles) is well established and a number of DNA-modified solid nanoparticle systems have been applied to thermal denaturation analysis of oligonucleotides. We report herein the non...... sequences (G or C-rich) to explore the applicability of the method for different triple helical assembly modes. We demonstrate advantages and limitations of the approach and proof the reversible and reproducible formation of liposome aggregates during thermal denaturation cycles. Nanoparticle tracking...

  2. Grain boundary and triple junction diffusion in nanocrystalline copper

    Energy Technology Data Exchange (ETDEWEB)

    Wegner, M., E-mail: m.wegner@uni-muenster.de; Leuthold, J.; Peterlechner, M.; Divinski, S. V., E-mail: divin@uni-muenster.de [Institut für Materialphysik, Universität Münster, Wilhelm-Klemm-Straße 10, D-48149, Münster (Germany); Song, X., E-mail: xysong@bjut.edu.cn [College of Materials Science and Engineering, Beijing University of Technology, 100124 Beijing (China); Wilde, G. [Institut für Materialphysik, Universität Münster, Wilhelm-Klemm-Straße 10, D-48149, Münster (Germany); Institute of Nanochemistry and Nanobiology, School of Environmental and Chemical Engineering, Shanghai University, 200444 Shanghai (China)

    2014-09-07

    Grain boundary and triple junction diffusion in nanocrystalline Cu samples with grain sizes, 〈d〉, of ∼35 and ∼44 nm produced by spark plasma sintering were investigated by the radiotracer method using the {sup 63}Ni isotope. The measured diffusivities, D{sub eff}, are comparable with those determined previously for Ni grain boundary diffusion in well-annealed, high purity, coarse grained, polycrystalline copper, substantiating the absence of a grain size effect on the kinetic properties of grain boundaries in a nanocrystalline material at grain sizes d ≥ 35 nm. Simultaneously, the analysis predicts that if triple junction diffusion of Ni in Cu is enhanced with respect to the corresponding grain boundary diffusion rate, it is still less than 500⋅D{sub gb} within the temperature interval from 420 K to 470 K.

  3. Triple dividends of water consumption charges in South Africa

    Science.gov (United States)

    Letsoalo, Anthony; Blignaut, James; de Wet, Theuns; de Wit, Martin; Hess, Sebastiaan; Tol, Richard S. J.; van Heerden, Jan

    2007-05-01

    The South African government is exploring ways to address water scarcity problems by introducing a water resource management charge on the quantity of water used in sectors such as irrigated agriculture, mining, and forestry. It is expected that a more efficient water allocation, lower use, and a positive impact on poverty can be achieved. This paper reports on the validity of these claims by applying a computable general equilibrium model to analyze the triple dividend of water consumption charges in South Africa: reduced water use, more rapid economic growth, and a more equal income distribution. It is shown that an appropriate budget-neutral combination of water charges, particularly on irrigated agriculture and coal mining, and reduced indirect taxes, particularly on food, would yield triple dividends, that is, less water use, more growth, and less poverty.

  4. Climate variability according to triple saros gravity cycles

    CERN Document Server

    Livingston, William R

    2013-01-01

    I describe a climate model which corresponds directly to eclipse cycles. The theory is based upon a similarity between the 54 year triple saros eclipse period and the periodicity of drought. I argue that eclipse shadows are an indication of gravity cycles, and that variable lunar gravitation is the most significant aspect of the eclipse process. I reinforce the idea that lunar gravitational forcing has a profound effect on the water vapor in Earth's atmosphere, and can affect the density and location of clouds. I explore the possibility that decadal variability of ocean surface levels may be explained by triple saros gravity cycles. I point out that lunar gravitation was excluded from the most significant climate report of 2007, and that climate data contradictions have been overlooked by researchers. I focus on the value of data that has not been aggregated into global averages. I touch upon the history of global warming, and I offer predictions based upon 54 year climate periodicity.

  5. Triple-horizon spherically symmetric spacetime and holographic principle

    CERN Document Server

    Dymnikova, Irina

    2012-01-01

    We present a family of spherically symmetric spacetimes, specified by the density profile of a vacuum dark energy, which have the same global structure as the de Sitter spacetime but the reduced symmetry which leads to a time-evolving and spatially inhomogeneous cosmological term. It connects smoothly two de Sitter vacua with different values of cosmological constant and corresponds to anisotropic vacuum dark fluid defined by symmetry of its stress-energy tensor which is invariant under the radial boosts. This family contains a special class distinguished by dynamics of evaporation of a cosmological horizon which evolves to the triple horizon with the finite entropy, zero temperature, zero curvature, infinite positive specific heat, and infinite scrambling time. Non-zero value of the cosmological constant in the triple-horizon spacetime is tightly fixed by quantum dynamics of evaporation of the cosmological horizon.

  6. Photodissociation of methyl formate: Conical intersections, roaming and triple fragmentation

    Energy Technology Data Exchange (ETDEWEB)

    Lin, King-Chuen; Tsai, Po-Yu [Department of Chemistry, National Taiwan University, Taipei 106, Taiwan (China); Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106, Taiwan (China); Chao, Meng-Hsuan [Department of Chemistry, National Taiwan University, Taipei 106, Taiwan (China); Kasai, Toshio [Department of Chemistry, National Taiwan University, Taipei 106, Taiwan (China); Graduate School of Science, Department of Chemistry, Osaka University, Toyonaka, 560-0043 Osaka (Japan); Lombardi, Andrea [Dipartimento di Chimica, Università di Perugia, 06123 Perugia (Italy); Palazzetti, Federico [Scuola Normale Superiore, 56126 Pisa (Italy); Aquilanti, Vincenzo [Dipartimento di Chimica, Università di Perugia, 06123 Perugia (Italy); Consiglio Nazionale delle Ricerche, Istituto di Struttura della Materia, 00016 Roma (Italy)

    2015-12-31

    The photodissociation channels of methyl formate have been extensively investigated by two different advanced experimental techniques, ion imaging and Fourier-Transform-Infrared emission spectroscopy, combined with quantum chemical calculations and molecular dynamics simulations. Our aim is to characterize the role of alternative routes to the conventional transition-state mediated pathway: the roaming and the triple fragmentation processes. The photolysis experiments, carried out at a range of laser wavelengths in the vicinity of the triple fragmentation threshold, beside the simulation of large bunches of classical trajectories with different initial conditions, have shown that both mechanisms share a common path that involves a conical intersection during the relaxation process from the electronic excited state S{sub 1} to the ground state S{sub 0}.

  7. EXTREME AO OBSERVATIONS OF TWO TRIPLE ASTEROID SYSTEMS WITH SPHERE

    Energy Technology Data Exchange (ETDEWEB)

    Yang, B.; Wahhaj, Z.; Dumas, C.; Marsset, M. [European Southern Observatory, Santiago (Chile); Beauvalet, L. [National Observatory, Rio de Janeiro (Brazil); Marchis, F.; Nielsen, E. L. [Carl Sagan Center at the SETI Institute, Mountain View, CA (United States); Vachier, F., E-mail: byang@eso.org [Institut de Mécanique Céleste et de Calcul des Éphémérides, Paris (France)

    2016-04-01

    We present the discovery of a new satellite of asteroid (130) Elektra—S/2014 (130) 1—in differential imaging and in integral field spectroscopy data over multiple epochs obtained with Spectro-Polarimetric High-contrast Exoplanet Research/Very Large Telescope. This new (second) moonlet of Elektra is about 2 km across, on an eccentric orbit, and about 500 km away from the primary. For a comparative study, we also observed another triple asteroid system, (93) Minerva. For both systems, component-resolved reflectance spectra of the satellites and primary were obtained simultaneously. No significant spectral difference was observed between the satellites and the primary for either triple system. We find that the moonlets in both systems are more likely to have been created by sub-disruptive impacts as opposed to having been captured.

  8. The Proteomic Landscape of Triple-Negative Breast Cancer

    Directory of Open Access Journals (Sweden)

    Robert T. Lawrence

    2015-04-01

    Full Text Available Triple-negative breast cancer is a heterogeneous disease characterized by poor clinical outcomes and a shortage of targeted treatment options. To discover molecular features of triple-negative breast cancer, we performed quantitative proteomics analysis of twenty human-derived breast cell lines and four primary breast tumors to a depth of more than 12,000 distinct proteins. We used this data to identify breast cancer subtypes at the protein level and demonstrate the precise quantification of biomarkers, signaling proteins, and biological pathways by mass spectrometry. We integrated proteomics data with exome sequence resources to identify genomic aberrations that affect protein expression. We performed a high-throughput drug screen to identify protein markers of drug sensitivity and understand the mechanisms of drug resistance. The genome and proteome provide complementary information that, when combined, yield a powerful engine for therapeutic discovery. This resource is available to the cancer research community to catalyze further analysis and investigation.

  9. Mosaic triple X syndrome in a female with primary amenorrhea

    Directory of Open Access Journals (Sweden)

    A Venkateshwari

    2012-01-01

    Full Text Available Background: Turner′s syndrome is the most common chromosomal abnormality in females, affecting 1 in 2,500 live female births. It is a result of absence of an X chromosome or the presence of a structurally abnormal X chromosome. Its most consistent clinical features are short stature and ovarian failure. Aim: The aim of the study was to report a rare case of mosaic triple X syndrome in a female with primary amenorrhea. Materials and Methods: The chromosomal analysis using GTG banding was carried out, which revealed a mosaicism with 45,XO/47,XXX chromosomal constitution. Fluorescent in situ hybridization was also carried out to further confirm the observation made in the study. Conclusion: The physical features presented by the female could be due to the 45,XO/47,XXX mosaicism and the karyotype analysis was consistent with the diagnosis and clinical symptoms. Triple X mosaicism was confirmed with conventional and molecular cytogenetic analysis.

  10. Intermolecular triple proton and deuteron transfer in crystalline 3,5-dimethylpyrazole studied by NMR, NQR, and x-ray methods

    Energy Technology Data Exchange (ETDEWEB)

    Wehrle, B.; Aguilar-Parrilla, F.; Limbach, H.H. (Universitaet Freiburg (West Germany)); de la Concepcion Foces-Foces, M.; Cano, F.H. (Instituto Rocasaolano, Madrid (Spain)); Elguero, J. (C.S.I.C., Madrid (Spain)); Baldy, A.; Pierrot, M. (Universite Aix-Marseille III (France)); Khurshid, M.M.T.; Larcombe-McDouall, J.B.; Smith, J.A.S. (King' s College, London (England))

    1989-09-13

    A combination of {sup 13}C, {sup 15}N magnetic resonance, {sup 14}N quadrupole double resonance, and x-ray studies of solid 3,5-dimethylpyrazole between 270 and 350 K has shown that the NH...N hydrogen bond units present in the crystal are dynamically disordered, so that each nitrogen atom is on average attached to half a hydrogen atom. The molecules form discrete hydrogen-bonded cyclic trimers, in which the hydrogen atoms move in a double minimum potential energy surface which is symmetrical, to within experimental error. The experimental evidence in this temperature range is consistent with disorder by means of correlated triple hydrogen jumps with an activation energy of 45 kJ mol{sup {minus}1}. There is a large kinetic hydrogen (HHH)/deuterium (DDD) isotope effort of >20 at 299 K and equal to 8 at 347 K.

  11. A new class of cyanine-like dyes with large bond-length alternation.

    Science.gov (United States)

    Ohira, Shino; Hales, Joel M; Thorley, Karl J; Anderson, Harry L; Perry, Joseph W; Brédas, Jean-Luc

    2009-05-06

    Cyanines, which represent a class of charged chromophores with an odd number of pi-conjugated carbons, display unique electronic and optical properties attributed to the strong electronic delocalization and the absence of any significant carbon-carbon bond-length alternation (BLA) along their backbones. The flatness of the corresponding electronic potential makes cyanine dyes the compounds to which simple free-electron theory can be applied in the most relevant way. Recently, cations of porphyrin dimers linked by a pi-conjugated bridge with an odd number of carbons and presenting alternating single and triple bonds were shown to possess linear and nonlinear optical properties analogous to those of cyanines. Here, by using a joint theoretical and experimental approach, we demonstrate the correspondence between cyanines and the new class of alkyne carbocations, in spite of their marked difference in BLA.

  12. On the Analysis Method of the Triple Tesh Cross Design

    Institute of Scientific and Technical Information of China (English)

    JinYi

    1995-01-01

    The analysis method of the triple test cross design has been discussed carefully form the two factor experiment design and the genetic models of additive-dominant effect and of epistasis effect-Two points different from the previous reprots have been concluded:(1)both the degrees of freedom of the orthogonal terms C2 and C3 are m;(2) the denominator in the F test to C2 and C3 is the error mean of square between plots.

  13. Tulczyjew triples in the constrained dynamics of strings

    Science.gov (United States)

    Grabowski, J.; Grabowska, K.; Urbański, P.

    2016-09-01

    We show that there exists a natural Tulczyjew triple in the dynamics of objects for which the standard (kinematic) configuration space TM is replaced with ∧n TM . In this framework, which is completely covariant, we derive geometrically phase equations, as well as Euler-Lagrange equations, including nonholonomic constraints into the picture. Dynamics of strings and a constrained Plateau problem in statics are particular cases of this framework.

  14. Triple AIM evaluation and application in advanced node

    Science.gov (United States)

    Wang, Gary C.; Lio, En Chuan; Hung, Yuting; Chen, Charlie; Wang, Sybil; Weng, Tang Chun; Lin, Bill; Yu, Chun Chi

    2016-03-01

    A novel method on advanced node for IBO (Image Based Overlay) data extraction accuracy is demonstrated in this work, and here some special design in triple-AIM (Advanced Imaging Metrology) is able to realize the approach. Since triple AIM design has 3 locations left for patterning layers insertion, a new design with 2 layers locations, location-A (inner) and location-B (middle), are generated by 1st pattering, i.e. once lithography exposure, and the 2 marks grouping are formed on dielectric through lithography and etching process with a predetermined overlay "zero offset" through original mask layout design, as illustrated in Fig. (1). And then, as following top photo resist layer, assumed location-C (outer), lithography patterning process, PR coating, exposure and development complete, full triple-AIM patterns is generated, and 3 sets of overlay data could be obtained, A to B, C to B, C to A. Through re-calculating the overlay raw data of current (2nd patterning layer) to previous (1st patterning layer) layer by averaging [C to B] and [C to A], then theoretically the data extraction of sites would be more accuracy, since the variation of local marks signal, induced by inline process instability, could be minimized through the raw data averaging procedure. Moreover, from raw data [A to B], an extra monitor function for detections of the inline process variation, marks selection and recipe setting optimization could be obtained, since marks in [A] and [BB] locations are both generated in 1st patterning, and with the target "zero". So if the raw data [A to BB] is bigger or smaller than "zero" in some degree, there should be some process issue or marks condition setting error in triple-AIM design.

  15. Lifestyle Triple P: a parenting intervention for childhood obesity

    Directory of Open Access Journals (Sweden)

    Gerards Sanne MPL

    2012-04-01

    Full Text Available Abstract Background Reversing the obesity epidemic requires the development and evaluation of childhood obesity intervention programs. Lifestyle Triple P is a parent-focused group program that addresses three topics: nutrition, physical activity, and positive parenting. Australian research has established the efficacy of Lifestyle Triple P, which aims to prevent excessive weight gain in overweight and obese children. The aim of the current randomized controlled trial is to assess the effectiveness of the Lifestyle Triple P intervention when applied to Dutch parents of overweight and obese children aged 4–8 years. This effectiveness study is called GO4fit. Methods/Design Parents of overweight and obese children are being randomized to either the intervention or the control group. Those assigned to the intervention condition receive the 14-week Lifestyle Triple P intervention, in which they learn a range of nutritional, physical activity and positive parenting strategies. Parents in the control group receive two brochures, web-based tailored advice, and suggestions for exercises to increase active playing at home. Measurements are taken at baseline, directly after the intervention, and at one year follow-up. Primary outcome measure is the children’s body composition, operationalized as BMI z-score, waist circumference, and fat mass (biceps and triceps skinfolds. Secondary outcome measures are children’s dietary behavior and physical activity level, parenting practices, parental feeding style, parenting style, parental self-efficacy, and body composition of family members (parents and siblings. Discussion Our intervention is characterized by a focus on changing general parenting styles, in addition to focusing on changing specific parenting practices, as obesity interventions typically do. Strengths of the current study are the randomized design, the long-term follow-up, and the broad range of both self-reported and objectively measured

  16. Triple I method and interval valued fuzzy reasoning

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The aims of this paper are: (i) to show that the CRI method should be improved and remould into the triple I method, (ii) to propose a new type of fuzzy reasoning with multiple rules of which the premise of each rule is an interval valued fuzzy subset, (iii) to establish the "fire one or leave (FOOL)" principle as pretreatment for solving the fuzzy reasoning problem mentioned in (ii), and (iv) to solve the problem mentioned in (ii).

  17. Triple I method and interval valued fuzzy reasoning

    Institute of Scientific and Technical Information of China (English)

    王国俊

    2000-01-01

    The aims of this paper are.- (i) to show that the CRI method should be improved and remould into the triple I method, (ii) to propose a new type of fuzzy reasoning with multiple rules of which the premise of each rule is an interval valued fuzzy subset, (iii) to establish the "fire one or leave (FOOL)" principle as pretreatment for solving the fuzzy reasoning problem mentioned in (ii), and (iv) to solve the problem mentioned in (ii).

  18. Conformational stability of triazolyl functionalized collagen triple helices.

    Science.gov (United States)

    Erdmann, Roman S; Wennemers, Helma

    2013-06-15

    Functionalized collagen is attractive for the development of synthetic biomaterials. Herein we present the functionalization of azidoproline containing collagen model peptides with various alkynes using click chemistry. The influence on the stability of the collagen triple helix of the stereochemistry of the introduced triazolyl prolines (4R or 4S), the position of their incorporation (Xaa or Yaa) and the substituents attached to them are shown. The results provide a useful guide for the optimal functionalization of collagen using click chemistry.

  19. AND BUSINESS INCUBATORS INTO THE TRIPLE HELIX CONCEPT

    Directory of Open Access Journals (Sweden)

    Sizova, Y.S.

    2016-04-01

    Full Text Available The article’s author endeavors to create a practical model of the Russian economy’s development while integrating such tools of supporting and stimulating entrepreneurship as business incubators and research and technology parks into the Triple Helix concept. The article points out that configurations fusing together the nation-state, business and science/education, possess a greater potential for development.

  20. Period tripling causes rotating spirals in agitated wet granular layers.

    Science.gov (United States)

    Huang, Kai; Rehberg, Ingo

    2011-07-08

    Pattern formation of a thin layer of vertically agitated wet granular matter is investigated experimentally. Rotating spirals with three arms, which correspond to the kinks between regions with different colliding phases, are the dominating pattern. This preferred number of arms corresponds to period tripling of the agitated granular layer, unlike predominantly subharmonic Faraday crispations in dry granular matter. The chirality of the spatiotemporal pattern corresponds to the rotation direction of the spirals.

  1. One-loop triple collinear splitting amplitudes in QCD

    CERN Document Server

    Badger, Simon; Peraro, Tiziano

    2015-01-01

    We study the factorisation properties of one-loop scattering amplitudes in the triple collinear limit and extract the universal splitting amplitudes for processes initiated by a gluon. The splitting amplitudes are derived from the analytic Higgs plus four partons amplitudes. We present compact results for primitive helicity splitting amplitudes making use of super-symmetric decompositions. The universality of the collinear factorisation is checked numerically against the full colour six parton squared matrix elements.

  2. Reduced form models of bond portfolios

    OpenAIRE

    Matti Koivu; Teemu Pennanen

    2010-01-01

    We derive simple return models for several classes of bond portfolios. With only one or two risk factors our models are able to explain most of the return variations in portfolios of fixed rate government bonds, inflation linked government bonds and investment grade corporate bonds. The underlying risk factors have natural interpretations which make the models well suited for risk management and portfolio design.

  3. 27 CFR 24.146 - Bonds.

    Science.gov (United States)

    2010-04-01

    .... (c) Wine vinegar plant bond. The proprietor of a wine vinegar plant who withdraws wine from a bonded wine premises without payment of tax for use in the manufacture of vinegar shall file a bond on TTB F 5510.2, Bond Covering Removal to and Use of Wine at Vinegar Plant, to ensure the payment of the tax...

  4. 27 CFR 26.69 - Strengthening bonds.

    Science.gov (United States)

    2010-04-01

    ... Liquors and Articles in Puerto Rico Bonds § 26.69 Strengthening bonds. In all cases where the penal sum of... surety to attain a sufficient penal sum, or give a new bond to cover the entire liability. Strengthening... penal sum. Strengthening bonds shall show the current date of execution and the effective date....

  5. Biophysical studies of matrix metalloproteinase/triple-helix complexes.

    Science.gov (United States)

    Fields, Gregg B

    2014-01-01

    Several members of the zinc-dependent matrix metalloproteinase (MMP) family catalyze collagen degradation. The structures of MMPs, in solution and solid state and in the presence and absence of triple-helical collagen models, have been assessed by NMR spectroscopy, small-angle X-ray scattering, and X-ray crystallography. Structures observed in solution exhibit flexibility between the MMP catalytic (CAT) and hemopexin-like (HPX) domains, while solid-state structures are relatively compact. Evaluation of the maximum occurrence (MO) of MMP-1 conformations in solution found that, for all the high MO conformations, the CAT and HPX domains are not in tight contact, and the residues of the HPX domain reported to be responsible for the binding to the collagen triple-helix are solvent exposed. A mechanism for collagenolysis has been developed based on analysis of MMP solution structures. Information obtained from solid-state structures has proven valuable for analyzing specific contacts between MMPs and the collagen triple-helix.

  6. Assembly of liposomes controlled by triple helix formation.

    Science.gov (United States)

    Jakobsen, Ulla; Vogel, Stefan

    2013-09-18

    Attachment of DNA to the surface of different solid nanoparticles (e.g., gold and silica nanoparticles) is well established, and a number of DNA-modified solid nanoparticle systems have been applied to thermal denaturation analysis of oligonucleotides. We report herein the noncovalent immobilization of oligonucleotides on the surface of soft nanoparticles (i.e., liposomes) and the subsequent controlled assembly by DNA triple helix formation. The noncovalent approach avoids tedious surface chemistry and necessary purification procedures and can simplify and extend the available methodology for the otherwise difficult thermal denaturation analysis of complex triple helical DNA assemblies. The approach is based on lipid modified triplex forming oligonucleotides (TFOs) which control the assembly of liposomes in solution in the presence of single- or double-stranded DNA targets. The thermal denaturation analysis is monitored by ultraviolet spectroscopy at submicromolar concentrations and compared to regular thermal denaturation assays in the absence of liposomes. We report on triplex forming oligonucleotides (TFOs) based on DNA and locked nucleic acid (LNA)/DNA hybrid building blocks and different target sequences (G or C-rich) to explore the applicability of the method for different triple helical assembly modes. We demonstrate advantages and limitations of the approach and show the reversible and reproducible formation of liposome aggregates during thermal denaturation cycles. Nanoparticle tracking analysis (NTA) and dynamic light scattering (DLS) show independently from ultraviolet spectroscopy experiments the formation of liposome aggregates.

  7. Correlation effects in 3D triple-Weyl semimetals

    Science.gov (United States)

    Zhang, Shi-Xin; Jian, Shao-Kai; Yao, Hong

    We study interaction effects, including short-range interactions and long-range Coulomb interactions, in three-dimensional topological triple-Weyl semimetals whose triple-Weyl points are protected by crystalline symmetries. In the low-energy effective field theory of triple-Weyl semimetals, by considering symmetries and utilizing Fierz identity, we find that there are only four independent short-range interaction terms. We then perform Wilsonian renormalization group analysis to determine the effect of short-range interactions at low energy and long distance by finding fixed points as well as stable strong-coupling limits. For those strong-coupling limits due to short-range interactions, spontaneous symmetry-breaking ordering is expected and is analyzed by self-consistent mean-field calculations combined with RG flow. For long-range Coulomb interactions, we find anisotropic screening effect, similar with the one in double-Weyl semimetals, and hence a qualitatively different fixed point from the Gaussian one.

  8. Unambiguous demonstration of triple-helix-directed gene modification.

    Science.gov (United States)

    Barre, F X; Ait-Si-Ali, S; Giovannangeli, C; Luis, R; Robin, P; Pritchard, L L; Helene, C; Harel-Bellan, A

    2000-03-28

    Triple-helix-forming oligonucleotides (TFOs), which can potentially modify target genes irreversibly, represent promising tools for antiviral therapies. However, their effectiveness on endogenous genes has yet to be unambiguously demonstrated. To monitor endogenous gene modification by TFOs in a yeast model, we inactivated an auxotrophic marker gene by inserting target sequences of interest into its coding region. The genetically engineered yeast cells then were treated with psoralen-linked TFOs followed by UV irradiation, thus generating highly mutagenic covalent crosslinks at the target site whose repair could restore gene function; the number of revertants and spectrum of mutations generated were quantified. Results showed that a phosphoramidate TFO indeed reaches its target sequence, forms crosslinks, and generates mutations at the expected site via a triplex-mediated mechanism: (i) under identical conditions, no mutations were generated by the same TFO at two other loci in the target strain, nor in an isogenic control strain carrying a modified target sequence incapable of supporting triple-helix formation; (ii) for a given target sequence, whether the triplex was formed in vivo on an endogenous gene or in vitro on an exogenous plasmid, the nature of the mutations generated was identical, and consistent with the repair of a psoralen crosslink at the target site. Although the mutation efficiency was probably too low for therapeutic applications, our results confirm the validity of the triple-helix approach and provide a means of evaluating the effectiveness of new chemically modified TFOs and analogs.

  9. Prenatal diagnosis and prognosis of triple X syndrome: 47, XXX.

    Science.gov (United States)

    Ben Hamouda, H; Mkacher, N; Elghezal, H; Bannour, H; Kamoun, M; Soua, H; Saad, A; Souissi, M M; Sfar, M T

    2009-11-01

    Triple X syndrome is a relatively common sex chromosomal abnormality occurring in 0,1% of live-born female infants. Most of these infants have a normal phenotype and only a few cases with 47, XXX karyotype have congenital malformations. We report three cases of triple X syndrome that were diagnosed prenatally by genetic amniocentesis for advanced maternal age and have been observed from birth to age of 3 to 12 years. A description of their growth and development is presented. The birth weight was normal in all patients and one of them had facial dysmorphism with right microphtalmia and auricular septal defect. During the first 2 years of life, the neuromotor development of these infants was not distinguishable from chromosomally normal children. By 3 years of age, two patients have a moderate developmental delay in speech and language. One girl 12-year-old had normal schooling. The diagnosis of the triple X syndrome can be never made because clinical demonstrations are not rather important to arouse the demand of a karyotype. Prenatal diagnosis is often made in front of the advanced maternal age. Expectant parents must be counseled as to the significance of this 47, XXX karyotype and prognostic information must be given.

  10. Direct Syn Addition of Two Silicon Atoms to a C≡C Triple Bond by Si-Si Bond Activation: Access to Reactive Disilylated Olefins.

    Science.gov (United States)

    Ahmad, Maha; Gaumont, Annie-Claude; Durandetti, Muriel; Maddaluno, Jacques

    2017-02-20

    A catalytic intramolecular silapalladation of alkynes affords, in good yields and stereoselectively, syn-disilylated heterocycles of different chemical structure and size. When applied to silylethers, this reaction leads to vinylic silanols that undergo a rhodium-catalyzed addition to activated olefins, providing the oxa-Heck or oxa-Michael products, depending on the reaction conditions.

  11. Halogen Bonding in Organic Synthesis and Organocatalysis.

    Science.gov (United States)

    Bulfield, David; Huber, Stefan M

    2016-10-01

    Halogen bonding is a noncovalent interaction similar to hydrogen bonding, which is based on electrophilic halogen substituents. Hydrogen-bonding-based organocatalysis is a well-established strategy which has found numerous applications in recent years. In light of this, halogen bonding has recently been introduced as a key interaction for the design of activators or organocatalysts that is complementary to hydrogen bonding. This Concept features a discussion on the history and electronic origin of halogen bonding, summarizes all relevant examples of its application in organocatalysis, and provides an overview on the use of cationic or polyfluorinated halogen-bond donors in halide abstraction reactions or in the activation of neutral organic substrates.

  12. Three methods to measure RH bond energies

    Energy Technology Data Exchange (ETDEWEB)

    Berkowitz, J. [Argonne National Lab., IL (United States); Ellison, G.B. [Univ. of Colorado, Boulder, CO (United States). Dept. of Chemistry and Biochemistry; Gutman, D. [Catholic Univ. of America, Washington, DC (United States). Dept. of Chemistry

    1993-03-21

    In this paper the authors compare and contrast three powerful methods for experimentally measuring bond energies in polyatomic molecules. The methods are: radical kinetics; gas phase acidity cycles; and photoionization mass spectroscopy. The knowledge of the values of bond energies are a basic piece of information to a chemist. Chemical reactions involve the making and breaking of chemical bonds. It has been shown that comparable bonds in polyatomic molecules, compared to the same bonds in radicals, can be significantly different. These bond energies can be measured in terms of bond dissociation energies.

  13. Reaction of Laser-Ablated Uranium and Thorium Atoms with H2Se: A Rare Example of Selenium Multiple Bonding.

    Science.gov (United States)

    Vent-Schmidt, Thomas; Andrews, Lester; Thanthiriwatte, K Sahan; Dixon, David A; Riedel, Sebastian

    2015-10-19

    The compounds H2ThSe and H2USe were synthesized by the reaction of laser-ablated actinide metal atoms with H2Se under cryogenic conditions following the procedures used to synthesize H2AnX (An = Th, U; X = O, S). The molecules were characterized by infrared spectra in an argon matrix with the aid of deuterium substitution and electronic structure calculations at the density functional theory level. The main products, H2ThSe and H2USe, are shown to have a highly polarized actinide-selenium triple bond, as found for H2AnS on the basis of electronic structure calculations. There is an even larger back-bonding of the Se with the An than found for the corresponding sulfur compounds. These molecules are of special interest as rare examples of multiple bonding of selenium to a metal, particularly an actinide metal.

  14. Two Comments on Bond Angles

    Science.gov (United States)

    Glaister, P.

    1997-09-01

    Tetrahedral Bond Angle from Elementary Trigonometry The alternative approach of using the scalar (or dot) product of vectors enables the determination of the bond angle in a tetrahedral molecule in a simple way. There is, of course, an even more straightforward derivation suitable for students who are unfamiliar with vectors, or products thereof, but who do know some elementary trigonometry. The starting point is the figure showing triangle OAB. The point O is the center of a cube, and A and B are at opposite corners of a face of that cube in which fits a regular tetrahedron. The required bond angle alpha = AÔB; and using Pythagoras' theorem, AB = 2(square root 2) is the diagonal of a face of the cube. Hence from right-angled triangle OEB, tan(alpha/2) = (square root 2) and therefore alpha = 2tan-1(square root 2) is approx. 109° 28' (see Fig. 1).

  15. Bond percolation on multiplex networks

    CERN Document Server

    Hackett, A; Gómez, S; Arenas, A; Gleeson, J P

    2015-01-01

    We present an analytical approach for bond percolation on multiplex networks and use it to determine the expected size of the giant connected component and the value of the critical bond occupation probability in these networks. We advocate the relevance of these tools to the modeling of multilayer robustness and contribute to the debate on whether any benefit is to be yielded from studying a full multiplex structure as opposed to its monoplex projection, especially in the seemingly irrelevant case of a bond occupation probability that does not depend on the layer. Although we find that in many cases the predictions of our theory for multiplex networks coincide with previously derived results for monoplex networks, we also uncover the remarkable result that for a certain class of multiplex networks, well described by our theory, new critical phenomena occur as multiple percolation phase transitions are present. We provide an instance of this phenomenon in a multipex network constructed from London rail and Eu...

  16. Accounting for the differences in the structures and relative energies of the highly homoatomic np pi-np pi (n > or = 3)-bonded S2I4 2+, the Se-I pi-bonded Se2I4 2+, and their higher-energy isomers by AIM, MO, NBO, and VB methodologies.

    Science.gov (United States)

    Brownridge, Scott; Crawford, Margaret-Jane; Du, Hongbin; Harcourt, Richard D; Knapp, Carsten; Laitinen, Risto S; Passmore, Jack; Rautiainen, J Mikko; Suontamo, Reijo J; Valkonen, Jussi

    2007-02-05

    + and Se2I42+. The difference in the structures of S2I42+ and Se2I42+ is related to the high strength of the S-S pi bond compared to the weak S-I sigma bond and the additional stabilization from increased delocalization of positive charge in the structure of S2I42+ compared to the structure of Se2I42+. The investigation of the E2X42+ series (E = S, Se, Te; X = Cl, Br, I) revealed that only S2I42+ adopts the highly np pi-np pi (n > or = 3)-bonded structure, while all other dications favor the pi-bonded Se2I42+ structure. Theoretical bond order calculations for S2I42+ confirm the previously presented experimentally based bond orders for S-S (2.1-2.3) and I-I (1.3-1.5) bonds. The S-S bond is determined to have the highest reported S-S bond order in an isolated compound and has a bond order that is either similar to or slightly less than the Si-Si bond order in the proposed triply bonded [(Me3Si)2CH]2(iPr)SiSi triple bond SiSi(iPr)[CH(SiMe3)2]2 depending on the definition of bond orders used.

  17. Triple-target microarray experiments: a novel experimental strategy

    Directory of Open Access Journals (Sweden)

    Cooke Howard J

    2004-02-01

    Full Text Available Abstract Background High-throughput, parallel gene expression analysis by means of microarray technology has become a widely used technique in recent years. There are currently two main dye-labelling strategies for microarray studies based on custom-spotted cDNA or oligonucleotides arrays: (I Dye-labelling of a single target sample with a particular dye, followed by subsequent hybridisation to a single microarray slide, (II Dye-labelling of two different target samples with two different dyes, followed by subsequent co-hybridisation to a single microarray slide. The two dyes most frequently used for either method are Cy3 and Cy5. We propose and evaluate a novel experiment set-up utilising three differently labelled targets co-hybridised to one microarray slide. In addition to Cy3 and Cy5, this incorporates Alexa 594 as a third dye-label. We evaluate this approach in line with current data processing and analysis techniques for microarrays, and run separate analyses on Alexa 594 used in single-target, dual-target and the intended triple-target experiment set-ups (a total of 18 microarray slides. We follow this by pointing out practical applications and suitable analysis methods, and conclude that triple-target microarray experiments can add value to microarray research by reducing material costs for arrays and related processes, and by increasing the number of options for pragmatic experiment design. Results The addition of Alexa 594 as a dye-label for an additional – third – target sample works within the framework of more commonplace Cy5/Cy3 labelled target sample combinations. Standard normalisation methods are still applicable, and the resulting data can be expected to allow identification of expression differences in a biological experiment, given sufficient levels of biological replication (as is necessary for most microarray experiments. Conclusion The use of three dye-labelled target samples can be a valuable addition to the standard

  18. Performance bond: conditional or unconditional

    OpenAIRE

    Supardi, Azizan; Yaakob, Jamaluddin; Adnan, Hamimah

    2009-01-01

    In construction contracts, a 'performance bond' is a bond taken out by the contractor, usually with a bank or insurance company (in return for payment of a premium), for the benefit of and at the request of the employer, in a stipulated maximum sum of liability and enforceable by the employer in the event of the contractor's default, repudiation or insolvency, as stated by Nigel M Robinson et. al. in his book, Construction Law in Singapore and Malaysia. He further added that there are two typ...

  19. BOND ORDERING IN NONCRYSTALLINE SOLIDS

    OpenAIRE

    Revesz, A.

    1982-01-01

    From the analysis of optical properties of noncrystalline (nc) and the corresponding crystalline solids with predominantly covalent bonds a bonding order parameter, F, is derived. This parameter reveals differences between nc solids which are characterized by similar degree of short-range-order as, e.g., amorphous Si (F ≤ 0.8) and vitreous SiO2 (F ≈ 1). Both the optical and electrical properties indicate that, in contrast to amorphous solids, the electronic states in vitreous solids may remai...

  20. Integrating Compassionate, Collaborative Care (the "Triple C") Into Health Professional Education to Advance the Triple Aim of Health Care.

    Science.gov (United States)

    Lown, Beth A; McIntosh, Sharrie; Gaines, Martha E; McGuinn, Kathy; Hatem, David S

    2016-03-01

    Empathy and compassion provide an important foundation for effective collaboration in health care. Compassion (the recognition of and response to the distress and suffering of others) should be consistently offered by health care professionals to patients, families, staff, and one another. However, compassion without collaboration may result in uncoordinated care, while collaboration without compassion may result in technically correct but depersonalized care that fails to meet the unique emotional and psychosocial needs of all involved. Providing compassionate, collaborative care (CCC) is critical to achieving the "triple aim" of improving patients' health and experiences of care while reducing costs. Yet, values and skills related to CCC (or the "Triple C") are not routinely taught, modeled, and assessed across the continuum of learning and practice. To change this paradigm, an interprofessional group of experts recently recommended approaches and a framework for integrating CCC into health professional education and postgraduate training as well as clinical care. In this Perspective, the authors describe how the Triple C framework can be integrated and enhance existing competency standards to advance CCC across the learning and practice continuum. They also discuss strategies for partnering with patients and families to improve health professional education and health care design and delivery through quality improvement projects. They emphasize that compassion and collaboration are important sources of professional, patient, and family satisfaction as well as critical aspects of professionalism and person-centered, relationship-based high-quality care.

  1. The Quest for Metal-Metal Quadruple and Quintuple Bonds in Metal Carbonyl Derivatives: Nb2(CO)9 and Nb2(CO)8.

    Science.gov (United States)

    Tang, Lihong; Luo, Qiong; Li, Qian-Shu; Xie, Yaoming; King, R Bruce; Schaefer, Henry F

    2012-03-13

    The synthesis by Power and co-workers of the first metal-metal quintuple bond (Science2005, 310, 844) is a landmark in inorganic chemistry. The 18-electron rule suggests that Nb2(CO)9 and Nb2(CO)8 are candidates for binary metal carbonyls containing metal-metal quadruple and quintuple bonds, respectively. Density functional theory (MPW1PW91 and BP86) indeed predicts structures having very short Nb-Nb distances of ∼2.5 Å for Nb2(CO)9 and ∼2.4 Å for Nb2(CO)8 as well as relatively large Nb-Nb Wiberg bond indices supporting these high formal Nb-Nb bond orders. However, analysis of the frontier molecular orbitals of these unbridged structures suggests formal Nb≡Nb triple bonds and 16-electron metal configurations. This contrasts with an analysis of the frontier orbitals in a model chromium(I) alkyl linear CH3CrCrCH3, which confirms the generally accepted presence of chromium-chromium quintuple bonds in such molecules. The presence of Nb≡Nb triple bonds rather than quadruple or quintuple bonds in the Nb2(CO)n (n = 9, 8) structures frees up d(xy) and d(x(2)-y(2)) orbitals for dπ→pπ* back-bonding to the carbonyl groups. The lowest energy Nb2(CO)n structures (n = 9, 8) are not these unbridged structures but structures having bridging carbonyl groups of various types and formal Nb-Nb orders no higher than three. Thus, the two lowest energy Nb2(CO)9 structures have Nb≡Nb triple bond distances of ∼2.8 Å and three semibridging carbonyl groups, leading to a 16-electron configuration rather than an 18-electron configuration for one of the niobium atoms. The lowest energy structure of the highly unsaturated Nb2(CO)8 is unusual since it has a formal single Nb-Nb bond of length ∼3.1 Å and two four-electron donor η(2)-μ-CO groups, thereby giving each niobium atom only a 16-electron configuration.

  2. Effect of hydration on the stability of the collagen-like triple-helical structure of [4(R)-hydroxyprolyl-4(R)-hydroxyprolylglycine]10.

    Science.gov (United States)

    Kawahara, Kazuki; Nishi, Yoshinori; Nakamura, Shota; Uchiyama, Susumu; Nishiuchi, Yuji; Nakazawa, Takashi; Ohkubo, Tadayasu; Kobayashi, Yuji

    2005-12-06

    X-ray analysis has been carried out on a crystal of the collagen model peptide (Hyp(R)-Hyp(R)-Gly)10 [where Hyp(R) is 4(R)-hydroxyproline] with 1.5 A resolution. The triple-helical structure of (Hyp(R)-Hyp(R)-Gly)10 has the same helical parameters and Rich and Crick II hydrogen bond patterns as those of other collagen model peptides. However, our full-length crystal structure revealed that almost all consecutive Hyp(R) residues take the up-up pucker in contrast to putative down-up puckering propensities of other collagen model peptides. The unique feature of thermodynamic parameters associated with the conformational transition of this peptide from triple helix to single coil is that both enthalpy and entropy changes of the transition are much smaller than those of other model peptides such as (Pro-Pro-Gly)10 and (Pro-Hyp(R)-Gly)10. To corroborate the precise structural information including main- and side-chain dihedral angles and intra- and interwater bridge networks, we estimated the degrees of hydration by comparing molecular volumes observed experimentally in solution to those calculated ones from the crystal structure. The results showed that the degree of hydration of (Hyp(R)-Hyp(R)-Gly)10 is comparable to that of (Pro-Hyp(R)-Gly)10 in the triple-helical state, but the former was more highly hydrated than (Pro-Hyp(R)-Gly)10 in the single-coil state. Because hydration reduces the enthalpy due to the formation of a hydrogen bond with a water molecule and diminishes the entropy due to the restriction of water molecules surrounding a peptide molecule, we concluded that the high thermal stability of (Hyp(R)-Hyp(R)-Gly)10 is able to be described by its high hydration in the single-coil state.

  3. On double bonds in fullerenes

    Directory of Open Access Journals (Sweden)

    Stepenshchikov D. G.

    2016-03-01

    Full Text Available Various distributions of double carbon bonds in the fullerenes have been considered in the paper from the point that they are absent in the pentagonal rings. The appropriate classification of the fullerenes has been built. The results may be used when modeling the fullerenes of a given topology and calculating their physical-chemical properties

  4. Essays on European bond markets

    NARCIS (Netherlands)

    Cheung, Y.C.

    2005-01-01

    This dissertation focused on a number of issues that are of importance in the current European bond market. In the past years, the fiscal policy of the Eurozone members, advances in the technology of trading platforms and the introduction of a single currency have reshaped the fixed income markets i

  5. A reconstruction theorem for Connes-Landi deformations of commutative spectral triples

    CERN Document Server

    Ćaćić, Branimir

    2014-01-01

    We state and prove an extension of Connes's reconstruction theorem for commutative spectral triples to so-called Connes-Landi or isospectral deformations of commutative spectral triples along the action of a compact Abelian Lie group $G$. We do so by proposing an abstract definition for such spectral triples, where noncommutativity is entirely governed by a class in the second group cohomology of the Pontrjagin dual of $G$, and then showing that such spectral triples are well-behaved under further Connes-Landi deformation, thereby allowing for both quantisation from and dequantisation to $G$-equivariant abstract commutative spectral triples. We also construct a discrete analogue of the Connes--Dubois-Violette splitting homomorphism, which then allows us to conclude that sufficiently well-behaved rational Connes--Landi deformations of commutative spectral triples are almost-commutative in the general, topologically non-trivial sense.

  6. Stabilization of collagen-model, triple-helical peptides for in vitro and in vivo applications.

    Science.gov (United States)

    Bhowmick, Manishabrata; Fields, Gregg B

    2013-01-01

    The triple-helical structure of collagen has been accurately reproduced in numerous chemical and recombinant model systems. Triple-helical peptides and proteins have found application for dissecting collagen-stabilizing forces, isolating receptor- and protein-binding sites in collagen, mechanistic examination of collagenolytic proteases, and development of novel biomaterials. Introduction of native-like sequences into triple-helical constructs can reduce the thermal stability of the triple-helix to below that of the physiological environment. In turn, incorporation of nonnative amino acids and/or templates can enhance triple-helix stability. We presently describe approaches by which triple-helical structure can be modulated for use under physiological or near-physiological conditions.

  7. Elucidating pH-dependent collagen triple helix formation through interstrand hydroxyproline-glutamic acid interactions.

    Science.gov (United States)

    Chen, Liwei; Cai, Shuting; Lim, Jaehong; Lee, Su Seong; Lee, Song-Gil

    2015-02-09

    Here, we describe systematic explorations into the molecular basis underlying hydroxyproline-mediated interstrand interactions on the triple-helical stability of collagen-mimetic peptides containing glutamic acid residues. Our studies reveal that the triple-helical stability of these peptides relies on the existence of interstrand interactions between hydroxyprolines and glutamic acid residues that are pH dependent. These unique interactions have been used to engineer collagen peptides that form triple helices on demand through pH control.

  8. Outcome of Inhaler Withdrawal in Patients Receiving Triple Therapy for COPD

    OpenAIRE

    Kim, Sae Ahm; Lee, Ji-Hyun; Kim, Eun-Kyung; Kim, Tae-Hyung; Kim, Woo Jin; Lee, Jin Hwa; Yoon, Ho Il; Baek, Seunghee; Lee, Jae Seung; Oh, Yeon-Mok; Lee, Sang-Do

    2015-01-01

    Background The purpose of this study was to document outcomes following withdrawal of a single inhaler (step-down) in chronic obstructive pulmonary disease (COPD) patients on triple therapy (long-acting muscarinic antagonist and a combination of long-acting β2-agonists and inhaled corticosteroid), which a common treatment strategy in clinical practice. Methods Through a retrospective observational study, COPD patients receiving triple therapy over 2 years (triple group; n=109) were compared w...

  9. A first-order dynamical model of hierarchical triple stars and its application

    CERN Document Server

    Xu, Xingbo; Fu, Yanning

    2015-01-01

    For most hierarchical triple stars, the classical double two-body model of zeroth-order cannot describe the motions of the components under the current observational accuracy. In this paper, Marchal's first-order analytical solution is implemented and a more efficient simplified version is applied to real triple stars. The results show that, for most triple stars, the proposed first-order model is preferable to the zeroth-order model either in fitting observational data or in predicting component positions.

  10. Effect of moisture, saliva, and blood contamination on the shear bond strength of brackets bonded with a conventional bonding system and self-etched bonding system

    Science.gov (United States)

    Prasad, Mandava; Mohamed, Shamil; Nayak, Krishna; Shetty, Sharath Kumar; Talapaneni, Ashok Kumar

    2014-01-01

    Background: The success of bonding brackets to enamel with resin bonding systems is negatively affected by contamination with oral fluids such as blood and saliva. The new self-etch primer systems combine conditioning and priming agents into a single application, making the procedure more cost effective. Objective: The purpose of the study was to investigate the effect of moisture, saliva and blood contamination on shear bond strength of orthodontic brackets bonded with conventional bonding system and self-etch bonding system. Materials and Methods: Each system was examined under four enamel surface conditions (dry, water, saliva, and blood), and 80 human teeth were divided into two groups with four subgroups each of 10 according to enamel surface condition. Group 1 used conventional bonding system and Group 2 used self-etched bonding system. Subgroups 1a and 2a under dry enamel surface conditions; Subgroups 1b and 2b under moist enamel surface condition; Subgroups 3a and 3b under saliva enamel surface condition and Subgroup 4a and 4b under blood enamel surface condition. Brackets were bonded, and all the samples were then submitted to a shear bond test with a universal testing machine with a cross head speed of 1mm/sec. Results: The results showed that the contamination reduced the shear bond strength of all groups. In self-etch bonding system water and saliva had significantly higher bond strength when compared to other groups. Conclusion: It was concluded that the blood contamination showed lowest bond strength from both bonding systems. Self-etch bonding system resulted in higher bond strength than conventional bonding system under all conditions except the dry enamel surface. PMID:24678210

  11. Stabilities and Spectroscopy of Hydrogen Bonding Complexes Formed by 2,4-Bis(acrylamido)pyrimidines

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ye; LI Ting; TENG Qi-Wen

    2008-01-01

    Hydrogen bonds play important roles to living organisms containing pyrimidine-based derivatives.The electronic structures of the hydrogen bonding complexes formed by 2,4-bis(acrylamido)pyrimidine (2,4-BAAP) derivatives with 1-substituted uracil were studied using Austin Model 1 (AMl) and density function theory (DFT) methods.The UV and NMR spectra of the complexes were calculated with the INDO/CIS (configuration interaction for singlet in intermediate neglect of differential overlap) and B3LYP/6-31G(d)methods.It was shown that the complexes could be formed via the triple hydrogen bonding between two monomers owing to the negative binding energies.The binding energies of the complexes were weakened in the presence of substituents,but this weakening effect depended on the simultaneous influence of the electronic and steric effects.The binding energies of the complexes were also decreased owing to the formation of the isomeric complexes in the presence of piperidyl on 2,4-BAAP.The energy gaps of the complexes were lessened in the presence of electron-donating groups.Holes and electrons were easily injected to the complexes due to the extension of the conjugation chain.The first UV absorptions of the complexes relative to those of the parent compound were red-shifted because of the narrow energy gaps.The chemical shifts of the carbon atoms on the C=O bonds in the complexes were changed downfield.

  12. Optimising hydrogen bonding in solid wood

    DEFF Research Database (Denmark)

    Engelund, Emil Tang

    2009-01-01

    The chemical bonds of wood are both covalent bonds within the wood polymers and hydrogen bonds within and between the polymers. Both types of bonds are responsible for the coherence, strength and stiffness of the material. The hydrogen bonds are more easily modified by changes in load, moisture...... and temperature. The distribution of bond lengths was examined using infrared spectroscopy (ATR-FTIR) both prior to treatments and after. The results show that the absorbance bands of the spectra related to the hydroxyl and carboxyl stretching vibrations were changed by the treatments. Apparently, the first...

  13. Method for fusion bonding thermoplastic composites

    Energy Technology Data Exchange (ETDEWEB)

    Benatar, A.; Gutowski, T.G.

    1986-10-01

    Bonding of thermoplastic composites is a critical step in the manufacture of aerospace structures. The objective of this project is to investigate different methods for fusion bonding thermoplastic composites quickly, with a good bond strength, and without warping and deconsolidation. This is best accomplished by heating and melting the thermoplastic on the bond surface only, and then pressing the parts together for a fusion bond. For this purpose, a variety of surface heating techniques were examined for bonding of PEEK and J Polymer composites. These included: resistance heating, infrared heating, induction heating, dielectric/microwave heating, and ultrasonic welding. 20 references, 10 figures, 1 table.

  14. The Geometry of Quantum Lens Spaces: Real Spectral Triples and Bundle Structure

    Energy Technology Data Exchange (ETDEWEB)

    Sitarz, Andrzej, E-mail: andrzej.sitarz@uj.edu.pl [Jagiellonian University, Institute of Physics (Poland); Venselaar, Jan Jitse, E-mail: jvensel1@gwdg.de [Georg-August Universität Göttingen, Mathematisches Institut (Germany)

    2015-12-15

    We study almost real spectral triples on quantum lens spaces, as orbit spaces of free actions of cyclic groups on the spectral geometry on the quantum group SU{sub q}(2). These spectral triples are given by weakening some of the conditions of a real spectral triple. We classify the irreducible almost real spectral triples on quantum lens spaces and we study unitary equivalences of such quantum lens spaces. Applying a useful characterization of principal U(1)-fibrations in noncommutative geometry, we show that all such quantum lens spaces are principal U(1)-fibrations over quantum teardrops.

  15. Pembrolizumab and Ruxolitinib Phosphate in Treating Patients With Metastatic Stage IV Triple Negative Breast Cancer

    Science.gov (United States)

    2017-03-15

    Breast Carcinoma Metastatic in the Bone; Estrogen Receptor Negative; HER2/Neu Negative; Progesterone Receptor Negative; Recurrent Breast Carcinoma; Stage IV Breast Cancer; Triple-Negative Breast Carcinoma

  16. Effect of sterically demanding substituents on the conformational stability of the collagen triple helix.

    Science.gov (United States)

    Erdmann, Roman S; Wennemers, Helma

    2012-10-17

    The effect of sterically demanding groups at proline residues on the conformational stability of the collagen triple helix was examined. The thermal stabilities (T(m) and ΔG) of eight different triple helices derived from collagen model peptides with (4R)- or (4S)-configured amidoprolines bearing either methyl or bulkier tert-butyl groups in the Xaa or Yaa position were determined and served as a relative measure for the conformational stability of the corresponding collagen triple helices. The results show that sterically demanding substituents are tolerated in the collagen triple helix when they are attached to (4R)-configured amidoprolines in the Xaa position or to (4S)-configured amidoprolines in the Yaa position. Structural studies in which the preferred conformation of (4R)- or (4S)-configured amidoproline were overlaid with the Pro and Hyp residues within a crystal structure of collagen revealed that the sterically demanding groups point to the outside of these two triple helices and thereby do not interfere with the formation of the triple helix. In all of the other examined collagen derivatives with lower stability of the triple helices, the acetyl or pivaloyl residues point toward the inside of the triple helix and clash with a residue of the neighboring strand. The results also revealed that unfavorable steric dispositions affect the conformational stability of the collagen triple helix more than unfavorable ring puckers of the proline residues. The results are useful for the design of functionalized collagen based materials.

  17. Strength of Bond Covenants and Bond Assessment Framework

    Directory of Open Access Journals (Sweden)

    Noel Yahanpath

    2012-06-01

    Full Text Available We examine bond covenants of 29 New Zealand bond issues between 2001 and 2007.Results from the study indicate that protection provided for bondholders is weak and limited.On average, only 2-3 types of covenants are embedded with the issues and only 27% of thesecovenants provide full protection to the bondholders. However, bondholders are not compensated for taking the additional risk. We propose an alternative assessment framework that directly assesses the level of protection offered to bondholders. We calculate thecovenant quality score for the issues and classify them into four levels of protection: very high protection, moderate, low and very low. Recent legislative changes will go some way towards improving investor protection and confidence, but the effect is yet to be seen. This proposed scoring framework can be used by potential investors to complement the traditional credit ratings when making their investment decisions.

  18. 王中之王——Triple H

    Institute of Scientific and Technical Information of China (English)

    刘杰

    2009-01-01

    仅拿出一小会,忘记所有的绰号和俗语。纵观所有数不尽的冠军头衔和比赛。无视他是WWE历史上两个最重要组合的领导者,还有他克服被专家视作永远禁赛的伤痛。你只需要用两个字来概括Triple H: The Game(游戏主宰)。

  19. Triple Encrypted Holographic Storage and Digital Holographic System

    Institute of Scientific and Technical Information of China (English)

    ZHU Yi-Chao; ZHANG Jia-Sen; GONG Qi-Huang

    2008-01-01

    We propose a triple encrypted holographic memory containing a digital holographic system. The original image is encrypted using double random phase encryption and stored in a LiNbO3:Fe crystal with shift-multiplexing. Both the reference beams of the memory and the digital holographic system are random phase encoded. We theoretically and experimentally demonstrate the encryption and decryption of multiple images and the results show high quality and good fault tolerance. The total key length of this system is larger than 4.7×1033.

  20. Noncommutative geometry, Grand Symmetry and twisted spectral triple

    CERN Document Server

    Devastato, Agostino

    2015-01-01

    In the noncommutative geometry approach to the standard model we discuss the possibility to derive the extra scalar field sv- initially suggested by particle physicist to stabilize the electroweak vacuum - from a "grand algebra" that contains the usual standard model algebra. We introduce the Connes-Moscovici twisted spectral triples for the Grand Symmetry model, to cure a technical problem, that is the appearance, together with the field sv, of unbounded vectorial terms. The twist makes these terms bounded, and also permits to understand the breaking making the computation of the Higgs mass compatible with the 126 GeV experimental value.

  1. Noncommutative geometry, Grand Symmetry and twisted spectral triple

    Science.gov (United States)

    Devastato, Agostino

    2015-08-01

    In the noncommutative geometry approach to the standard model we discuss the possibility to derive the extra scalar field sv - initially suggested by particle physicist to stabilize the electroweak vacuum - from a “grand algebra” that contains the usual standard model algebra. We introduce the Connes-Moscovici twisted spectral triples for the Grand Symmetry model, to cure a technical problem, that is the appearance, together with the field sv, of unbounded vectorial terms. The twist makes these terms bounded, and also permits to understand the breaking making the computation of the Higgs mass compatible with the 126 GeV experimental value.

  2. Research on ambiguity resolution aided with triple difference

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The ambiguity resolution in the field of GPS is investigated in detail. A new algorithm to resolve the ambiguity is proposed. The algorithm first obtains the floating resolution of the ambiguity aided with triple difference measurement. Decorrelation of searching space is done by reducing the ambiguity covariance matrix's dimension to overcome the possible sick factorization of the matrix brought by Z-transformation. In simulation, the proposed algorithm is compared with least-squares ambiguity decorrelation adjustment (LAMBDA). The result shows that the proposed algorithm is better than LAMBDA because of lesser resolving time, which approximately reduces 20% resolving time. Thus, the proposed algorithm adapts to the high dynamic real-time applications.

  3. Triple-layer Absorptive Structures for Shock Wave Blast Protection

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Triple-layer absorptive structure is designed to reinforce a missile silo against shock wave blasts. An energy-absorbing layer and a cushion layer overlay the circular silo cover made of reinforced concrete. The dynamic stress analysis is performed by ABAQUS/Explicit. The mesoscopic structure of the energy absorbing layer is designed as an assembly of ductile tubes containing crushable cellular ceramics. Combined mesoscopic and macroscopic simulations indicate that the structure can enhance the survivability of a missile silo against blast waves.

  4. The fantasy of the triple threat in academic dentistry.

    Science.gov (United States)

    Koka, Sreenivas

    2009-01-01

    One of the fond hopes of academic administrators is to assemble a faculty with a core of triple threats: individuals who excel in teaching, research, and patient care. This report describes the quest of one faculty member to achieve this T3 status. Gradually it has become clear that excelling in any of these areas is more than a full-time commitment in itself. Although each experience contributes to the skill set of a professional, a realistic view of excellence means concentrating one's efforts.

  5. Nuclear collective flow from gaussian fits to triple differential distributions

    Energy Technology Data Exchange (ETDEWEB)

    Gosset, J.; Demoulins, M.; Babinet, R.; Cavata, C.; Fanet, H.; L' Hote, D.; Lucas, B.; Poitou, J.; Valette, O. (CEA Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France). Dept. de Physique Nucleaire); Lemaire, M.C. (Laboratoire National Saturne, Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France)); Alard, J.P.; Augerat, J.; Bastid, N.; Charmensat, P.; Dupieux, P.; Fraysse, L.; Marroncle, J.; Montarou, G.; Parizet, M.J.; Qassoud, D.; Rahmani, A. (Clermont-Ferrand-2 Univ., 63 - Aubiere (France). Lab. de Physique Corpusculaire); Brochard, F.; Gorodetzky, P.; Racca, C. (Strasbourg-1 Univ., 67 (France). Centre de Recherches Nucleaires)

    1990-09-13

    In order to study the nuclear collective flow, the triple differential momentum distributions of charged baryons are fitted to a simple anisotropic gaussian distribution, within an acceptance which removes most of the spectator contribution. The adjusted flow angle and aspect ratios are corrected for systematic errors in the determination of the reaction plane. This method has been tested with Monte Carlo simulations and applied to experimental results and intranuclear cascade simulations of argon-nucleus collisions at 400 MeV per nucleon. (orig.).

  6. Recent results on the hierarchical triple system HD 150136

    Science.gov (United States)

    Gosset, E.; Berger, J. P.; Absil, O.; Le Bouquin, J. B.; Sana, H.; Mahy, L.; De Becker, M.

    2013-06-01

    HD 150136 is a hierarchical triple system, non-thermal radio emitter, made of three O stars totalling some 130 solar masses. The 2.67-day inner orbit is rather well-known. Recent works derived a good approximation for the outer orbit with a period of 3000 days. We report here on interferometric observations that allow us to angularly resolve the outer orbit. First evidences for an astrometric displacement are given. The determination of the outer system orbit gives access to the inclinations of the systems and to the masses, including the one of the O3-O3.5 primary star.

  7. Characterization of a Deswapped Triple Mutant Bovine Odorant Binding Protein

    Directory of Open Access Journals (Sweden)

    Roberto Favilla

    2011-04-01

    Full Text Available The stability and functionality of GCC-bOBP, a monomeric triple mutant of bovine odorant binding protein, was investigated, in the presence of denaturant and in acidic pH conditions, by both protein and 1-aminoanthracene ligand fluorescence measurements, and compared to that of both bovine and porcine wild type homologues. Complete reversibility of unfolding was observed, though refolding was characterized by hysteresis. Molecular dynamics simulations, performed to detect possible structural changes of the monomeric scaffold related to the presence of the ligand, pointed out the stability of the β-barrel lipocalin scaffold.

  8. Current approaches in treatment of triple-negative breast cancer

    Institute of Scientific and Technical Information of China (English)

    Hanan Ahmed Wahba; Hend Ahmed El-Hadaad

    2015-01-01

    Triple-negative breast cancer (TNBC) is diagnosed more frequently in younger and premenopausal women and is highly prevalent in African American women. TNBC is a term derived from tumors that are characterized by the absence of ER, PgR, and HER2. So patients with TNBC do not beneift from hormonal or trastuzumab-based therapies. TNBCs are biologically aggressive, although some reports suggest that they respond to chemotherapy better than other types of breast cancer, prognosis remains poor. hTis is due to:shortened disease-free interval in the adjuvant and neoadjuvant setting and a more aggressive course in the metastatic setting.

  9. Triple Negative Breast Cancer Team Project — EDRN Public Portal

    Science.gov (United States)

    Triple negative breast cancers (TNBC), comprise 15-20% of breast cancers, and are associated with later stage at diagnosis, increased mortality, and occur more frequently in younger women where mammographic screening is less reliable. TNBCs are more likely to be diagnosed by physical exam than by mammographic screening. There is an unmet clinical need for biomarkers for the early detection of TNBC. Here, we are proposing the development of a plasma-based biomarker panel for the routine screening of women over the age of 40 for TNBC that can be used to identify women for further imaging.

  10. Polygonal triple (Kotz) osteotomy (over 10 years experience)

    OpenAIRE

    Sen, Cengiz; Gunes, Taner; Erdem, Mehmet; Ozger, Harzem; Tozun, I. Remzi

    2006-01-01

    We evaluated the results of polygonal triple (Kotz) osteotomy for the treatment of acetabular dysplasia over 10 years. This study included 31 hips of 27 patients who had the Kotz osteotomy for acetabular dysplasia. The mean age was 21.5 years. We performed the original Kotz osteotomy for the first 22 hips (group I), while the modified Kotz osteotomy through an intra-pelvic approach without damage to the abductor muscle was applied for the last 9 hips (group II). Patients were evaluated by cli...

  11. Achieving Shared Triple Bottom Line (TBL) Value Creation

    DEFF Research Database (Denmark)

    Tate, Wendy; Bals, Lydia

    2016-01-01

    While the economic and environmental dimensions of the triple bottom line (TBL) have been covered extensively by management theory and practice, the social dimension remains largely underrepresented. The resource-based view (RBV) of the firm and the natural resource-based view (NRBV) of the firm...... are revisited to lay the theoretical foundation for exploring how the social dimension might be addressed. Social capabilities are then explored by looking at the social entrepreneurship literature and illustrative cases with the purpose of elaborating RBV toward a social resource-based view (SRBV) of the firm...

  12. Long-term stability test of a triple GEM detector

    CERN Document Server

    Adak, R P; Das, S; Ghosal, D; Ghosh, S K; Mondal, A; Nag, D; Nayak, T K; Patra, R N; Prasad, S K; Raha, S; Sahu, P K; Sahu, S; Swain, S

    2016-01-01

    The main aim of the study is to perform the long-term stability test of gain of the single mask triple GEM detector. A simple method is used for this long- term stability test using a radioactive X-ray source with high activity. The test is continued till accumulation of charge per unit area > 12.0 mC/mm2. The details of the chamber fabrication, the test set-up, the method of measurement and the test results are presented in this paper.

  13. Construction of Spectral Triples Starting from Fredholm Modules

    OpenAIRE

    Schrohe, E.; Walze, M.; Warzecha, J. -M.

    1998-01-01

    Let (A,H,F) be a p-summable Fredholm module where the algebra A= C \\Gamma is generated by a discrete group of unitaries in L(H) which is of polynomial growth r. Then we construct a spectral triple (A,H,D) with F= sign D which is q-summable for each q > p+r+1. In case (A,H,F) is (p,\\infty)-summable we obtain (q,\\infty)-summability of (A,H,D) for each q > p+r+1.

  14. Eccentricity evolution in hierarchical triple systems with eccentric outer binaries

    CERN Document Server

    Georgakarakos, Nikolaos

    2014-01-01

    We develop a technique for estimating the inner eccentricity in hierarchical triple systems, with the inner orbit being initially circular, while the outer one is eccentric. We consider coplanar systems with well separated components and comparable masses. The derivation of short period terms is based on an expansion of the rate of change of the Runge-Lenz vector. Then, the short period terms are combined with secular terms, obtained by means of canonical perturbation theory. The validity of the theoretical equations is tested by numerical integrations of the full equations of motion.

  15. A computational approach for the annotation of hydrogen-bonded base interactions in crystallographic structures of the ribozymes

    Energy Technology Data Exchange (ETDEWEB)

    Hamdani, Hazrina Yusof, E-mail: hazrina@mfrlab.org [School of Biosciences and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi (Malaysia); Advanced Medical and Dental Institute, Universiti Sains Malaysia, Bertam, Kepala Batas (Malaysia); Artymiuk, Peter J., E-mail: p.artymiuk@sheffield.ac.uk [Dept. of Molecular Biology and Biotechnology, Firth Court, University of Sheffield, S10 T2N Sheffield (United Kingdom); Firdaus-Raih, Mohd, E-mail: firdaus@mfrlab.org [School of Biosciences and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi (Malaysia)

    2015-09-25

    A fundamental understanding of the atomic level interactions in ribonucleic acid (RNA) and how they contribute towards RNA architecture is an important knowledge platform to develop through the discovery of motifs from simple arrangements base pairs, to more complex arrangements such as triples and larger patterns involving non-standard interactions. The network of hydrogen bond interactions is important in connecting bases to form potential tertiary motifs. Therefore, there is an urgent need for the development of automated methods for annotating RNA 3D structures based on hydrogen bond interactions. COnnection tables Graphs for Nucleic ACids (COGNAC) is automated annotation system using graph theoretical approaches that has been developed for the identification of RNA 3D motifs. This program searches for patterns in the unbroken networks of hydrogen bonds for RNA structures and capable of annotating base pairs and higher-order base interactions, which ranges from triples to sextuples. COGNAC was able to discover 22 out of 32 quadruples occurrences of the Haloarcula marismortui large ribosomal subunit (PDB ID: 1FFK) and two out of three occurrences of quintuple interaction reported by the non-canonical interactions in RNA (NCIR) database. These and several other interactions of interest will be discussed in this paper. These examples demonstrate that the COGNAC program can serve as an automated annotation system that can be used to annotate conserved base-base interactions and could be added as additional information to established RNA secondary structure prediction methods.

  16. Shear bond strength of two resin cements to human root dentin using three dentin bonding agents.

    Science.gov (United States)

    Gogos, C; Stavrianos, C; Kolokouris, I; Economides, N; Papadoyannis, I

    2007-01-01

    This study compared the bond strength of two resin cements to human root dentin when used with three bonding agents. The materials used were Rely X ARC and Perma Cem, two one-bottle bonding agents (Single Bond, Bond-1) and one self-etching bonding agent (Clearfil SE Bond). The dentin was obtained from single rooted human teeth, and the specimens were treated with either 15% EDTA or 37% phosphoric acid to remove the smear layer, except in groups where the self-etching bonding agent was used. The resin cements were placed on dentin surfaces with the use of bonding agents. Shear bond strength (SBS) was tested using a single plane shear test assembly. The dentin specimens were divided into 10 groups. Eight groups were pre-treated with EDTA or phosphoric acid to remove the smear layer, followed by a bonding agent (Bond-1 or Single Bond) and resin cement (Rely X or Perma Cem). In the two remaining groups, the smear layer was left intact, and the two resins cements were used in combination with the self-etching bonding agent (Clearfil SE Bond). No statistically significant differences were observed among the eight groups treated with one-bottle bonding agents. The mean bond strengths of the two groups treated with the self-etching bonding agent did not differ significantly from each other but were both significantly greater than the bond strengths of all the other groups. The results of this study also showed that EDTA can be used as an alternative to phosphoric acid in bonding procedures for resin cements. However, the bond strengths of resin cements, in combination with a self-etching bonding agent, were significantly greater than those of the same cements when used with one-bottle bonding agents.

  17. Electronic properties of interfaces produced by silicon wafer hydrophilic bonding

    Energy Technology Data Exchange (ETDEWEB)

    Trushin, Maxim

    2011-07-15

    The thesis presents the results of the investigations of electronic properties and defect states of dislocation networks (DNs) in silicon produced by wafers direct bonding technique. A new insight into the understanding of their very attractive properties was succeeded due to the usage of a new, recently developed silicon wafer direct bonding technique, allowing to create regular dislocation networks with predefined dislocation types and densities. Samples for the investigations were prepared by hydrophilic bonding of p-type Si (100) wafers with same small misorientation tilt angle ({proportional_to}0.5 ), but with four different twist misorientation angles Atw (being of < , 3 , 6 and 30 , respectively), thus giving rise to the different DN microstructure on every particular sample. The main experimental approach of this work was the measurements of current and capacitance of Schottky diodes prepared on the samples which contained the dislocation network at a depth that allowed one to realize all capabilities of different methods of space charge region spectroscopy (such as CV/IV, DLTS, ITS, etc.). The key tasks for the investigations were specified as the exploration of the DN-related gap states, their variations with gradually increasing twist angle Atw, investigation of the electrical field impact on the carrier emission from the dislocation-related states, as well as the establishing of the correlation between the electrical (DLTS), optical (photoluminescence PL) and structural (TEM) properties of DNs. The most important conclusions drawn from the experimental investigations and theoretical calculations can be formulated as follows: - DLTS measurements have revealed a great difference in the electronic structure of small-angle (SA) and large-angle (LA) bonded interfaces: dominating shallow level and a set of 6-7 deep levels were found in SA-samples with Atw of 1 and 3 , whereas the prevalent deep levels - in LA-samples with Atw of 6 and 30 . The critical twist

  18. Cooperativity in Surface Bonding and Hydrogen Bonding of Water and Hydroxyl at Metal Surfaces

    DEFF Research Database (Denmark)

    Schiros, T.; Ogasawara, H.; Naslund, L. A.;

    2010-01-01

    of the mixed phase at metal surfaces. The surface bonding can be considered to be similar to accepting a hydrogen bond, and we can thereby apply general cooperativity rules developed for hydrogen-bonded systems. This provides a simple understanding of why water molecules become more strongly bonded...... to the surface upon hydrogen bonding to OH and why the OH surface bonding is instead weakened through hydrogen bonding to water. We extend the application of this simple model to other observed cooperativity effects for pure water adsorption systems and H3O+ on metal surfaces.......We examine the balance of surface bonding and hydrogen bonding in the mixed OH + H2O overlayer on Pt(111), Cu(111), and Cu(110) via density functional theory calculations. We find that there is a cooperativity effect between surface bonding and hydrogen bonding that underlies the stability...

  19. Analysis of the Clinicopathologic Features and Prognosis in Triple-Negative Breast Cancer

    Institute of Scientific and Technical Information of China (English)

    Dehong Yang; Hong Liu; Jing Zhao

    2008-01-01

    OBJECTIVE To investigate the clinical and pathological features,as well as prognosis in triple-negative breast cancer patients.METHODS A total of 509 cases of operable breast cancer from January,2002 to June,2002 treated in the Cancer Hospital of Tianjin Medical University were analyzed.The Her-2,ER and PR status was determined using immunohistochemistry.Of the total cases,one group was identified as triple negative breast cancer,ie defined as ER,PR and Her-2 negative.The other group was nontriple-negative breast cancer.Clinicopathologic features of the groups were compared and 5-year disease-free survival (DFS)analyzed by the Kaplan-Meier method.RESULTS Of the total cases,21.4% (109/509) of cases were found to be triple- negative while 78.6% (400/509) were non-triplenegative.The triple negative group had higher incidence rates than the non-triple-negative group of the medullary type and Grade Ⅲ tumors (P < 0.05).There was no other difference in the clinicopathologic features between the 2 groups.From follow-up to June,2007,21.1% (23/109) of the triple-negative group and 12.7%(51/400) of the non-triple negative group had a local recurrence or distant metastasis,resulting in a significant difference (P < 0.05).In the triple-negative group and non-triple-negative group,5-year DFS were 78.9% and 87.3% respectively.There was a statistically significant difference between the 2 groups (P = 0.031).CONCLUSION Compared with non-triple-negative breast cancer,triple-negative breast cancer patients have an increased likehood of a local recurrence or distant metastasis and a poorer prognosis.

  20. "Triple-bottom-line" assessment of urban stormwater projects.

    Science.gov (United States)

    Taylor, A C; Fletcher, T D

    2006-01-01

    New guidelines have been developed and trialled in Australia to assist urban stormwater managers to assess options for projects that aim to improve urban waterway health. These guidelines help users to examine the financial, ecological and social dimensions of projects (i.e., the so-called "triple-bottom-line"). Features of the assessment process described in the guidelines include use of multi criteria analysis, input from technical experts as well as non-technical stakeholders, and provision of three alternative levels of assessment to suit stormwater managers with differing needs and resources. This paper firstly provides a background to the new guidelines and triple-bottom-line assessment. The assessment methodology promoted in the new guidelines is then briefly summarised. This methodology is compared and contrasted with European guidelines from the "SWARD" project that have been primarily developed for assessing the relative sustainability of options involving urban water supply and sewerage assets. Finally, the paper discusses how assessment methodologies that evaluate the financial, ecological and social dimensions of projects can, under some circumstances, be used to evaluate the relative progress of options for urban water management on a journey towards the widely pursued, but vaguely defined goal of "sustainable development".

  1. Benign metastasizing leiomyoma in triple location: lungs, parametria and appendix

    Science.gov (United States)

    Raś, Renata; Książek, Mariusz; Skręt-Magierło, Joanna; Kąziołka, Wojciech; Fudali, Ludmiła; Filipowska, Justyna; Skręt, Andrzej

    2016-01-01

    Benign metastasizing leiomyoma (BML) usually are situated in one organ, most often in lungs. BML patients typically have a history of uterine leiomyoma treated with hysterectomy, myomectomy or subtotal hysterectomy. The aim of the study was to present the case of a 53-year-old woman with triple location in the lungs, parametria and appendix. She had undergone a myomectomy 26 years earlier. In 2015, she was admitted to the surgical department because of abdominal pain, whereupon a cholecystectomy was performed. CT scans showed pelvic mass with pulmonary metastasis. Upon discharge the patient was referred to the Gynecology Clinic, where a laparotomy was performed. The intraoperative findings were: 1) uterus with multiple leiomyomas, 2) four tumors in the parametria, 3) tumor connected to the appendix. A subtotal hysterectomy, with a bilateral salpingo-oophorectomy, removal of the tumors from the parametria and appendectomy was performed. Pathology confirmed the diagnosis based on morphology and immunohistochemical staining (strongly positive for estrogen receptors and SMA, while Ki67 was very low, below 1%). Upon postoperative recovery, the patient was referred to the Thoracic Surgery Department. During the thoracotomy, multiple nodes, surrounded by lung parenchyma, were revealed. Wedge resection was performed, for localized pulmonary lesions, and sent for pathological examination. The final pathological diagnosis was benign metastasizing leiomyomatosis. In conclusion, the triple location of BML could possibly be a result of a parallel different metastasizing mechanism, although it is impossible to exclude one mechanism, which may be the cause of the metastases in three locations. PMID:27582687

  2. A new high voltage SOILDMOS with triple RESURF structure

    Institute of Scientific and Technical Information of China (English)

    Hu Xiarong; Zhang Bo; Luo Xiaorong; Yao Guoliang; Chen Xi; Li Zhaoji

    2011-01-01

    A novel triple RESURF (T-resurf) SOILDMOS structure is proposed.This structure has a P-type buried layer.Firstly,the depletion layer can extend on both sides of the P-buried layer,serving as a triple RESURF and leading to a high drift doping and a low on-resistance.Secondly,at a high doping concentration of the drift region,the P-layer can reduce high bulk electric field in the drift region and enhance the vertical electric field at the drain side,which results in uniform bulk electric field distributions and an enhanced BV.The proposed structure is used in SOI devices for the first time.The T-resurf SOILDMOS with BV =315 V is obtained by simulation on a 6 μm-thick SOI layer over a 2 μm-thick buried oxide layer,and its Rsp is reduced from 16.5 to 13.8 mΩ.cm2 in comparison with the double RESURF (D-resurf) SOILDMOS.When the thickness of the SOI layer increases,T-resurf SOILDMOS displays a more obvious effect on the enhancement of BV2/Ron.It reduces Rsp by 25% in 400 V SOILDMOS and by 38% in 550 V SOI LDMOS compared with the D-resurf structure.

  3. Bridging disparate symptoms of schizophrenia: a triple network dysfunction theory.

    Science.gov (United States)

    Nekovarova, Tereza; Fajnerova, Iveta; Horacek, Jiri; Spaniel, Filip

    2014-01-01

    Schizophrenia is a complex neuropsychiatric disorder with variable symptomatology, traditionally divided into positive and negative symptoms, and cognitive deficits. However, the etiology of this disorder has yet to be fully understood. Recent findings suggest that alteration of the basic sense of self-awareness may be an essential distortion of schizophrenia spectrum disorders. In addition, extensive research of social and mentalizing abilities has stressed the role of distortion of social skills in schizophrenia.This article aims to propose and support a concept of a triple brain network model of the dysfunctional switching between default mode and central executive network (CEN) related to the aberrant activity of the salience network. This model could represent a unitary mechanism of a wide array of symptom domains present in schizophrenia including the deficit of self (self-awareness and self-representation) and theory of mind (ToM) dysfunctions along with the traditional positive, negative and cognitive domains. We review previous studies which document the dysfunctions of self and ToM in schizophrenia together with neuroimaging data that support the triple brain network model as a common neuronal substrate of this dysfunction.

  4. Bridging disparate symptoms of schizophrenia: a Triple network dysfunction theory

    Directory of Open Access Journals (Sweden)

    Tereza eNekovarova

    2014-05-01

    Full Text Available Schizophrenia is a complex neuropsychiatric disorder with variable symptomatology, traditionally divided into positive and negative symptoms, and cognitive deficits. Yet, the etiology of this disorder has yet to be fully understood.Recent findings suggest that alteration of the basic sense of self-awareness may be an essential distortion of schizophrenia spectrum disorders. In addition, extensive research of social and mentalizing abilities has stressed the role of distortion of social skills in schizophrenia.This article aims to propose and support a concept of triple brain network model of the dysfunctional switching between default mode and central executive network related to the aberrant activity of salience network. This model could represent a unitary mechanism of a wide array of symptom domains present in schizophrenia including the deficit of SELF (self-awareness and self-representation and theory of mind (ToM dysfunctions along with the traditional positive, negative and cognitive domains. We review previous studies which document the dysfunctions of SELF and ToM in schizophrenia together with neuroimaging data elucidating the triple brain network model as a common neuronal substrate of this dysfunction.

  5. Conformational preferences of substituted prolines in the collagen triple helix.

    Science.gov (United States)

    Mooney, Sean D; Kollman, Peter A; Klein, Teri E

    2002-07-05

    Researchers have recently questioned the role hydroxylated prolines play in stabilizing the collagen triple helix. To address these issues, we have developed new molecular mechanics parameters for the simulation of peptides containing 4(R)-fluoroproline (Flp), 4(R)-hydroxyproline (Hyp), and 4(R)-aminoproline (Amp). Simulations of peptides based on these parameters can be used to determine the components that stabilize hydroxyproline over proline in the triple helix. The dihedrals F-C-C-N, O-C-C-N, and N-C-C-N were built using a N-beta-ethyl amide model. One nanosecond simulations were performed on the trimers [(Pro-Pro-Gly)(10)](3), [(Pro-Hyp-Gly)(10)](3), [(Pro-Amp-Gly)(10)](3), [(Pro-Amp(1+)-Gly)(10)](3), and [(Pro-Flp-Gly)(10)](3) in explicit solvent. The results of our simulations suggest that pyrrolidine ring conformation is mediated by the strength of the gauche effect and classical electrostatic interactions.

  6. Overlay metrology solutions in a triple patterning scheme

    Science.gov (United States)

    Leray, Philippe; Mao, Ming; Baudemprez, Bart; Amir, Nuriel

    2015-03-01

    Overlay metrology tool suppliers are offering today several options to their customers: Different hardware (Image Based Overlay or Diffraction Based Overlay), different target designs (with or without segmentation) or different target sizes (from 5 um to 30 um). All these variations are proposed to resolve issues like robustness of the target towards process variations, be more representative of the design or increase the density of measurements. In the frame of the development of a triple patterning BEOL scheme of 10 nm node layer, we compare IBO targets (standard AIM, AIMid and multilayer AIMid). The metrology tools used for the study are KLA-Tencor's nextgeneration Archer 500 system (scatterometry- and imaging-based measurement technologies on the same tool). The overlay response and fingerprint of these targets will be compared using a very dense sampling (up to 51 pts per field). The benefit of indie measurements compared to the traditional scribes is discussed. The contribution of process effects to overlay values are compared to the contribution of the performance of the target. Different targets are combined in one measurement set to benefit from their different strengths (performance vs size). The results are summarized and possible strategies for a triple patterning schemes are proposed.

  7. A millisecond pulsar in a stellar triple system

    CERN Document Server

    Ransom, S M; Archibald, A M; Hessels, J W T; Kaplan, D L; van Kerkwijk, M H; Boyles, J; Deller, A T; Chatterjee, S; Schechtman-Rook, A; Berndsen, A; Lynch, R S; Lorimer, D R; Karako-Argaman, C; Kaspi, V M; Kondratiev, V I; McLaughlin, M A; van Leeuwen, J; Rosen, R; Roberts, M S E; Stovall, K

    2014-01-01

    Gravitationally bound three-body systems have been studied for hundreds of years and are common in our Galaxy. They show complex orbital interactions, which can constrain the compositions, masses, and interior structures of the bodies and test theories of gravity, if sufficiently precise measurements are available. A triple system containing a radio pulsar could provide such measurements, but the only previously known such system, B1620-26 (with a millisecond pulsar, a white dwarf, and a planetary-mass object in an orbit of several decades), shows only weak interactions. Here we report precision timing and multi-wavelength observations of PSR J0337+1715, a millisecond pulsar in a hierarchical triple system with two other stars. Strong gravitational interactions are apparent and provide the masses of the pulsar (1.4378(13) Msun, where Msun is the solar mass and the parentheses contain the uncertainty in the final decimal places) and the two white dwarf companions (0.19751(15) Msun and 0.4101(3) Msun), as well ...

  8. Viscous solution of the triple-shock reflection problem

    Science.gov (United States)

    Lau-Chapdelaine, S. S.-M.; Radulescu, M. I.

    2016-09-01

    The reflection of a triple-shock configuration was studied numerically in two dimensions using the Navier-Stokes equations. The flow field was initialized using three shock theory, and the reflection of the triple point on a plane of symmetry was studied. The conditions simulated a stoichiometric methane-oxygen detonation cell at low pressure on time scales preceding ignition when the gas was assumed to be inert. Viscosity was found to play an important role on some shock reflection mechanisms believed to accelerate reaction rates in detonations when time scales are small. A small wall jet was present in the double Mach reflection and increased in size with Reynolds number, eventually forming a small vortex. Kelvin-Helmholtz instabilities were absent, and there was no Mach stem bifurcation at Reynolds numbers corresponding to when the Mach stem had travelled distances on the scale of the induction length. Kelvin-Helmholtz instabilities are found to not likely be a source of rapid reactions in detonations at time scales commensurate with the ignition delay behind the Mach stem.

  9. The triple-mode pulsating variable V823 Cas

    CERN Document Server

    Jurcsik, J; Varadi, M; Henden, A; Hurta, Z; Lakatos, B; Posztobanyi, K; Klagyivik, P; Sodor, A; Hurta, Zs.

    2005-01-01

    Based on extended multicolour CCD photometry of the triple-mode radial pulsator V823 Cas we studied the properties of the coupling frequencies invoked by nonlinear processes. Our results support that a resonance connection as suggested by Antonello & Aikawa (1998) affects the mode coupling behaviour. The P1/P0 period ratio of V823 Cas has an "out of range" value if compared with the period ratios of the known double mode pulsators, while the P2/P1 period ratio is normal. The periods and period ratios cannot be consistently interpret without conflict with pulsation and/or evolution models. We attempt to interpret this failure by the suggestion that at present, the periods of V823 Cas are in a transient, resonance affected state, thus do not reflect the true parameters of the object. The anomalous period change behaviour of the fundamental and second overtone modes supports this idea. We have also raised the possibility that a f0 + f2 = 2f1 resonance may act in triple mode pulsators.

  10. The Triangle Anomaly in Triple-Regge Limits

    CERN Document Server

    White, Alan R

    2001-01-01

    Reggeized gluon interactions due to a single quark loop are studied in the full triple-regge limit and in closely related helicity-flip helicity-pole limits. Triangle diagram reggeon interactions are generated that include local axial-vector effective vertices. It is shown that the massless quark U(1) anomaly is present as an infra-red divergence in the interactions generated by maximally non-planar Feynman diagrams. A multi-regge asymptotic dispersion relation formalism is developed which provides a systematic counting of anomaly contributions. The 48 triple discontinuities in the dispersion relation are of two kinds. The first kind are to one-particle inclusive cross-sections. The second kind contains the anomaly and the multi-regge theory has some special features, including a signature conservation rule. It is shown that the anomaly is present only in multiple discontinuities obtained from the maximally non-planar diagrams and that in the scattering of elementary quarks or gluons the signature and color p...

  11. Pontryagin invariants and integral formulas for Milnor's triple linking number

    CERN Document Server

    DeTurck, Dennis; Komendarczyk, Rafal; Melvin, Paul; Shonkwiler, Clayton; Vela-Vick, David Shea

    2011-01-01

    To each three-component link in the 3-sphere, we associate a geometrically natural characteristic map from the 3-torus to the 2-sphere, and show that the pairwise linking numbers and Milnor triple linking number that classify the link up to link homotopy correspond to the Pontryagin invariants that classify its characteristic map up to homotopy. This can be viewed as a natural extension of the familiar fact that the linking number of a two-component link in 3-space is the degree of its associated Gauss map from the 2-torus to the 2-sphere. When the pairwise linking numbers are all zero, we give an integral formula for the triple linking number analogous to the Gauss integral for the pairwise linking numbers. The integrand in this formula is geometrically natural in the sense that it is invariant under orientation-preserving rigid motions of the 3-sphere, while the integral itself can be viewed as the helicity of a related vector field on the 3-torus.

  12. High efficiency triple-junction amorphous solar cells

    Science.gov (United States)

    Ishihara, T.; Terazono, S.; Sasaki, H.; Kawabata, K.; Itagaki, T.

    A fabrication technique for high-efficiency triple-junction a-SiGe:H and a-Si:H pin solar cells is described. The interfacial characteristics of the a-SiGe:H pin cell, which is used for the bottom cell, have been improved by inserting graded bandgap layers at both p/i and n/i interfaces. The photoconductivity of the a-SiGe:H film, prepared by diluting the silane and germane discharge with a large amount of H2 gas, has also been improved. For the a-Si:H pin cell, Vocs as high as 0.99 V have been achieved by optimizing deposition conditions for the microc-Si:H p-layer and a-Si:H i-layer. Thickness of each layer in the triple-junction cell has been adjusted to get maximum output current. A cell with conversion efficiency of 10.6 percent has been obtained for a cell size of 100 sq cm.

  13. Valence-Bond Theory and Chemical Structure.

    Science.gov (United States)

    Klein, Douglas J.; Trinajstic, Nenad

    1990-01-01

    Discussed is the importance of valence bond theory on the quantum-mechanical theory of chemical structure and the nature of the chemical bond. Described briefly are early VB theory, development of VB theory, modern versions, solid-state applications, models, treatment in textbooks, and flaws in criticisms of valence bond theory. (KR)

  14. 25 CFR 214.4 - Bonds.

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Bonds. 214.4 Section 214.4 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ENERGY AND MINERALS LEASING OF OSAGE RESERVATION LANDS, OKLAHOMA, FOR... reserved to change the amount of the bond in any particular case, or to require a new bond in...

  15. 27 CFR 19.516 - Bond account.

    Science.gov (United States)

    2010-04-01

    ... maximum penal sum, he shall maintain an account of his bond and he shall charge the bond with the amount... return. Where a bond in less than the maximum penal sum has been allocated among two or more plants, as... the penal sum allocated to that plant. (Sec. 201, Pub. L. 85-859, 72 Stat. 1356, as amended (26...

  16. 27 CFR 19.244 - Unit bond.

    Science.gov (United States)

    2010-04-01

    ... sum which represents the penal sum (computed in accordance with § 19.245) for operations at and withdrawals from each plant. If the penal sum of the bond covering a plant, or the penal sum allocated to any... reflected by the penal sum in the bond for such plant. The unit bond shall be conditioned that the...

  17. 27 CFR 19.243 - Withdrawal bond.

    Science.gov (United States)

    2010-04-01

    ... to each plant covered by the bond the part of the total sum which represents the penal sum (computed in accordance with § 19.245) for each such plant. If the penal sum of the bond covering a plant, or the penal sum allocated to any plant (where the bond covers more than one plant), is in an amount...

  18. 77 FR 72999 - Small Brewers Bond Reduction

    Science.gov (United States)

    2012-12-07

    ... publishing a temporary rule that for a period of three years modifies the penal sum for a brewer's bond where... calendar year. Under the temporary rule, for the next three years, the penal sum of the required bond is $1... proposes to adopt the $1,000 penal sum amount for the brewer's bond for such brewers as a...

  19. Implicit Hamiltonian formulation of bond graphs

    NARCIS (Netherlands)

    Golo, G.; Schaft, A.J. van der; Breedveld, P.C.; Maschke, B.M.

    2003-01-01

    This paper deals with mathematical formulation of bond graphs. It is proven that the power continuous part of bond graphs, the junction structure, can be associated with a Dirac structure and that equations describing a bond graph model correspond to an implicit port-controlled Hamiltonian system wi

  20. Hydroxide catalysis bonding of silicon carbide

    NARCIS (Netherlands)

    Veggel, A.A. van; Ende, D.A. van den; Bogenstahl, J.; Rowan, S.; Cunningham, W.; Gubbels, G.H.M.; Nijmeijer, H.

    2008-01-01

    For bonding silicon carbide optics, which require extreme stability, hydroxide catalysis bonding is considered [Rowan, S., Hough, J. and Elliffe, E., Silicon carbide bonding. UK Patent 040 7953.9, 2004. Please contact Mr. D. Whiteford for further information: D.Whiteford@admin.gla.ac.uk]. This techn

  1. Low temperature anodic bonding to silicon nitride

    DEFF Research Database (Denmark)

    Weichel, Steen; Reus, Roger De; Bouaidat, Salim;

    2000-01-01

    Low-temperature anodic bonding to stoichiometric silicon nitride surfaces has been performed in the temperature range from 3508C to 4008C. It is shown that the bonding is improved considerably if the nitride surfaces are either oxidized or exposed to an oxygen plasma prior to the bonding. Both bulk...

  2. Heat Bonding of Irradiated Ethylene Vinyl Acetate

    Science.gov (United States)

    Slack, D. H.

    1986-01-01

    Reliable method now available for joining parts of this difficult-tobond material. Heating fixture encircles ethylene vinyl acetate multiplesocket part, providing heat to it and to tubes inserted in it. Fixtures specially designed to match parts to be bonded. Tube-and-socket bonds made with this technique subjected to tensile tests. Bond strengths of 50 percent that of base material obtained consistently.

  3. 36 CFR 9.48 - Performance bond.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Performance bond. 9.48... MINERALS MANAGEMENT Non-Federal Oil and Gas Rights § 9.48 Performance bond. (a) Prior to approval of a plan of operations, the operator shall be required to file a suitable performance bond with...

  4. 43 CFR 23.9 - Performance bond.

    Science.gov (United States)

    2010-10-01

    ... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Performance bond. 23.9 Section 23.9 Public... LANDS § 23.9 Performance bond. (a)(1) Upon approval of an exploration plan or mining plan, the operator shall be required to file a suitable performance bond of not less than $2,000 with satisfactory...

  5. 36 CFR 9.13 - Performance bond.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Performance bond. 9.13... MINERALS MANAGEMENT Mining and Mining Claims § 9.13 Performance bond. (a) Upon approval of a plan of operations the operator shall be required to file a suitable performance bond with satisfactory...

  6. 25 CFR 216.8 - Performance bond.

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Performance bond. 216.8 Section 216.8 Indians BUREAU OF... RECLAMATION OF LANDS General Provisions § 216.8 Performance bond. (a) Upon approval of an exploration plan or mining plan, the operator shall be required to file a suitable performance bond of not less than...

  7. INVESTIGATION OF BONDING IN OXIDE-FIBER (WHISKER) REINFORCED METALS.

    Science.gov (United States)

    CERAMIC FIBERS , BONDING), (*COMPOSITE MATERIALS, BONDING), (*BONDING, CERAMIC FIBERS ), ALUMINUM COMPOUNDS, OXIDES, ZIRCONIUM, NICKEL, TITANIUM, CHROMIUM, SINGLE CRYSTALS, VACUUM, SHEAR STRESSES, SURFACE PROPERTIES, ADDITIVES.

  8. Molecular characteristics and metastasis predictor genes of triple-negative breast cancer: a clinical study of triple-negative breast carcinomas.

    Directory of Open Access Journals (Sweden)

    Wen-Hung Kuo

    Full Text Available BACKGROUND: Triple-negative breast cancer is a subtype of breast cancer with aggressive tumor behavior and distinct disease etiology. Due to the lack of an effective targeted medicine, treatment options for triple-negative breast cancer are few and recurrence rates are high. Although various multi-gene prognostic markers have been proposed for the prediction of breast cancer outcome, most of them were proven clinically useful only for estrogen receptor-positive breast cancers. Reliable identification of triple-negative patients with a favorable prognosis is not yet possible. METHODOLOGY/PRINCIPAL FINDINGS: Clinicopathological information and microarray data from 157 invasive breast carcinomas were collected at National Taiwan University Hospital from 1995 to 2008. Gene expression data of 51 triple-negative and 106 luminal breast cancers were generated by oligonucleotide microarrays. Hierarchical clustering analysis revealed that the majority (94% of triple-negative breast cancers were tightly clustered together carrying strong basal-like characteristics. A 45-gene prognostic signature giving 98% predictive accuracy in distant recurrence of our triple-negative patients was determined using the receiver operating characteristic analysis and leave-one-out cross validation. External validation of the prognostic signature in an independent microarray dataset of 59 early-stage triple-negative patients also obtained statistical significance (hazard ratio 2.29, 95% confidence interval (CI 1.04-5.06, Cox P=0.04, outperforming five other published breast cancer prognostic signatures. The 45-gene signature identified in this study revealed that TGF-β signaling of immune/inflammatory regulation may play an important role in distant metastatic invasion of triple-negative breast cancer. CONCLUSIONS/SIGNIFICANCE: Gene expression data and recurrence information of triple-negative breast cancer were collected and analyzed in this study. A novel set of 45-gene

  9. 19 CFR 125.32 - Merchandise delivered to a bonded store or bonded warehouse.

    Science.gov (United States)

    2010-04-01

    ... warehouse. 125.32 Section 125.32 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND... Merchandise delivered to a bonded store or bonded warehouse. When merchandise is carried, carted or lightered to and received in a bonded store or bonded warehouse, the proprietor or his representative...

  10. Triple Helix Systems: An Analytical Framework for Innovation Policy and Practice in the Knowledge Society

    Science.gov (United States)

    Ranga, Marina; Etzkowitz, Henry

    2013-01-01

    This paper introduces the concept of Triple Helix systems as an analytical construct that synthesizes the key features of university--industry--government (Triple Helix) interactions into an "innovation system" format, defined according to systems theory as a set of components, relationships and functions. Among the components of Triple…

  11. Triple helix conformation-specific blinking of Cy3 in DNA.

    Science.gov (United States)

    Kawai, Kiyohiko; Maruyama, Atsushi

    2015-03-21

    We report that Cy3 undergoes triple helix conformation-specific blinking in DNA. Blinking patterns were affected by the stabilization of the Hoogsteen base-pair, suggesting that not only the presence but also the fluctuating behaviour of the triple helix can be monitored by the changes in the Cy3 blinking patterns.

  12. Procollagen triple helix assembly: an unconventional chaperone-assisted folding paradigm.

    Science.gov (United States)

    Makareeva, Elena; Leikin, Sergey

    2007-10-10

    Fibers composed of type I collagen triple helices form the organic scaffold of bone and many other tissues, yet the energetically preferred conformation of type I collagen at body temperature is a random coil. In fibers, the triple helix is stabilized by neighbors, but how does it fold? The observations reported here reveal surprising features that may represent a new paradigm for folding of marginally stable proteins. We find that human procollagen triple helix spontaneously folds into its native conformation at 30-34 degrees C but not at higher temperatures, even in an environment emulating Endoplasmic Reticulum (ER). ER-like molecular crowding by nonspecific proteins does not affect triple helix folding or aggregation of unfolded chains. Common ER chaperones may prevent aggregation and misfolding of procollagen C-propeptide in their traditional role of binding unfolded polypeptide chains. However, such binding only further destabilizes the triple helix. We argue that folding of the triple helix requires stabilization by preferential binding of chaperones to its folded, native conformation. Based on the triple helix folding temperature measured here and published binding constants, we deduce that HSP47 is likely to do just that. It takes over 20 HSP47 molecules to stabilize a single triple helix at body temperature. The required 50-200 microM concentration of free HSP47 is not unusual for heat-shock chaperones in ER, but it is 100 times higher than used in reported in vitro experiments, which did not reveal such stabilization.

  13. Micro-photoluminescence of GaAs/AlGaAs triple concentric quantum rings.

    Science.gov (United States)

    Abbarchi, Marco; Cavigli, Lucia; Somaschini, Claudio; Bietti, Sergio; Gurioli, Massimo; Vinattieri, Anna; Sanguinetti, Stefano

    2011-10-31

    A systematic optical study, including micro, ensemble and time resolved photoluminescence of GaAs/AlGaAs triple concentric quantum rings, self-assembled via droplet epitaxy, is presented. Clear emission from localized states belonging to the ring structures is reported. The triple rings show a fast decay dynamics, around 40 ps, which is expected to be useful for ultrafast optical switching applications.

  14. The effects of post coronary stenting triple antiplatelet therapies on platelet functions

    Institute of Scientific and Technical Information of China (English)

    韩雅玲

    2006-01-01

    Objective To explore the effects of triple antiplatelet therapy on platelet aggregation and activation in patients who underwent coronary stenting. Methods 120 inhospital coronary heart disease patients with coronary stenting were randomized into two groups receiving either triple antiplatelet drugs of aspirin and clopidogrel combined with cilostazol or dual antiplatelet drugs of aspirin and clopidogrel. On the first day after stenting cilostazol

  15. Nanostructured thin films for multiband-gap silicon triple junction solar cells

    NARCIS (Netherlands)

    Schropp, R.E.I.; Li, H. B. T.; Franken, R.H.; Rath, J.K.; van der Werf, C.H.M.; Schuttauf, J.A.; Stolk, R.L.

    2008-01-01

    By implementing nanostructure in multiband-gap proto-Si/proto-SiGe/nc-Si:H triple junction n–i–p solar cells, a considerable improvement in performance has been achieved. The unalloyed active layers in the top and bottom cell of these triple junction cells are deposited by Hot-Wire CVD. A significan

  16. Targeting MUC1-Mediated Tumor-Stromal Metabolic Interaction in Triple-Negative Breast Cancer

    Science.gov (United States)

    2016-11-01

    metabolism, glycolysis, mucin1, pentose phosphate pathway , triple negative breast cancer 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT...therapeutic target for breast cancer , particularly for the TNBC subtype. KEYWORDS: cancer metabolism, glycolysis, mucin1, pentose phosphate pathway ...AWARD NUMBER: W81XWH-13-1-0315 TITLE: Targeting MUC1-mediated tumor-stromal metabolic interaction in Triple- negative breast cancer PRINCIPAL

  17. Software-Enabled Project Management Techniques and Their Relationship to the Triple Constraints

    Science.gov (United States)

    Elleh, Festus U.

    2013-01-01

    This study investigated the relationship between software-enabled project management techniques and the triple constraints (time, cost, and scope). There was the dearth of academic literature that focused on the relationship between software-enabled project management techniques and the triple constraints (time, cost, and scope). Based on the gap…

  18. Temperature-insensitive frequency tripling for generating high-average power UV lasers.

    Science.gov (United States)

    Zhong, Haizhe; Yuan, Peng; Wen, Shuangchun; Qian, Liejia

    2014-02-24

    Aimed for generating high-average power ultraviolet (UV) lasers via third-harmonic generation (THG) consisting of frequency doubling and tripling stages, we numerically and experimentally demonstrate a novel frequency tripling scheme capable of supporting temperature-insensitive phase-matching (PM). Two cascaded tripling crystals, with opposite signs of the temperature derivation of phase-mismatch, are proposed and theoretically studied for improving the temperature-acceptance of PM. The proof-of-principle tripling experiment using two crystals of LBO and BBO shows that the temperature acceptance can be ~1.5 times larger than that of using a single tripling crystal. In addition, the phase shift caused by air dispersion, along with its influence on the temperature-insensitive PM, are also discussed. To illustrate the potential applications of proposed two-crystal tripling design in the high-average-power regime, full numerical simulations for the tripling process, are implemented based on the realistic crystals. The demonstrated two-crystal tripling scheme may provide a promising route to high-average-power THG in the UV region.

  19. Risk of regional recurrence in triple-negative breast cancer patients: a Dutch cohort study

    NARCIS (Netherlands)

    Roozendaal, van Lori M.; Smit, Leonie H.M.; Duijsens, Gaston H.N.M.; Vries, de Bart; Siesling, Sabine; Lobbes, Marc B.I.; Boer, de Maaike; Wilt, de Johannes H.W.; Smidt, Marjolein L.

    2016-01-01

    Triple-negative breast cancer is associated with early recurrence and low survival rates. Several trials investigate the safety of a more conservative approach of axillary treatment in clinically T1-2N0 breast cancer. Triple-negative breast cancer comprises only 15 % of newly diagnosed breast cancer

  20. The effectiveness of lifestyle triple P in the Netherlands: A randomized controlled trial

    NARCIS (Netherlands)

    Gerards, S.M.P.L.; Dagnelie, P.C.; Gubbels, J.S.; Buuren, S. van; Hamers, F.J.M.; Jansen, M.W.J.; Goot, O.H.M. van der; Vries, N.K. de; Sanders, M.R.; Kremers, S.P.J.

    2015-01-01

    Introduction Lifestyle Triple P is a general parenting intervention which focuses on preventing further excessive weight gain in overweight and obese children. The objective of the current study was to assess the effectiveness of the Lifestyle Triple P intervention in the Netherlands. Method We used

  1. Effectiveness of the triple P positive parenting program on parenting: A meta-analysis

    NARCIS (Netherlands)

    Graaf, I. de; Speetjens, P.; Smit, F.; Wolff, M. de; Tavecchio, L.

    2008-01-01

    Triple P is a parenting program intended to prevent and to provide treatment for severe behavioral, emotional, and developmental problems in children. The aim of this meta-analysis was to assess the effectiveness of Triple P Level 4 interventions on parenting styles and parental competency. Level 4

  2. Effectiveness of the Triple P Positive Parenting Program on Parenting: A Meta-Analysis

    Science.gov (United States)

    de Graaf, Ireen; Speetjens, Paula; Smit, Filip; de Wolff, Marianne; Tavecchio, Louis

    2008-01-01

    Triple P is a parenting program intended to prevent and to provide treatment for severe behavioral, emotional, and developmental problems in children. The aim of this meta-analysis was to assess the effectiveness of Triple P Level 4 interventions on parenting styles and parental competency. Level 4 is an intensive training program of 8-10 sessions…

  3. Improving orthodontic bonding to silver amalgam.

    Science.gov (United States)

    Zachrisson, B U; Büyükyilmaz, T; Zachrisson, Y O

    1995-01-01

    Flat rectangular tabs (n = 84) prepared from lathe-cut amalgam (ANA 2000) were subjected to aluminum oxide sandblasting or roughening with a diamond bur. Mandibular incisor edgewise brackets were bonded to these tabs using: Concise (Bis-GMA resin); one of three metal-bonding adhesives, viz., Superbond C&B (4-META resin), Panavia Ex (10-MDP Bis-GMA resin) or Geristore (composite base); and Concise after application of the intermediate resins All-Bond 2 Primers A+B, or the Scotch-Bond Multi-Purpose (SBMP) system. All specimens were stored in water at 37 degrees C for 24 hours before tensile bond strength testing. Alignment and uniform loading during testing were secured by engaging a hook in a circular ring soldered onto the bracket slot before bonding. Similar control brackets (n = 12) were bonded with Concise to extracted caries-free mandibular incisors. Bond failure sites were classified by a modified ARI system. Mean tensile bond strengths in the experimental group ranged from 3.4 to 6.4 MPa--significantly weaker than the control sample (13.2 MPa). Bond failure generally occurred at the amalgam/adhesive interface. Superbond C&B created the strongest bonds to amalgam; according to ANOVA and Duncan's Multiple-Range test, they were significantly stronger than the bonds with Panavia Ex and Concise, with Geristore in between. However, the bond strength of Concise to sandblasted amalgam was comparable to the Superbond C&B bonds when coupled with an intermediate application of All-Bond 2 Primers A+B. The SBMP, on the other hand, was less effective.(ABSTRACT TRUNCATED AT 250 WORDS)

  4. Common interruptions in the repeating tripeptide sequence of non-fibrillar collagens: sequence analysis and structural studies on triple-helix peptide models.

    Science.gov (United States)

    Thiagarajan, Geetha; Li, Yingjie; Mohs, Angela; Strafaci, Christopher; Popiel, Magdalena; Baum, Jean; Brodsky, Barbara

    2008-02-22

    Interruptions in the repeating (Gly-X1-X2)(n) amino acid sequence pattern are found in the triple-helix domains of all non-fibrillar collagens, and perturbations to the triple-helix at such sites are likely to play a role in collagen higher-order structure and function. This study defines the sequence features and structural consequences of the most common interruption, where one residue is missing from the tripeptide pattern, Gly-X1-X2-Gly-AA(1)-Gly-X1-X2, designated G1G interruptions. Residues found within G1G interruptions are predominantly hydrophobic (70%), followed by a significant amount of charged residues (16%), and the Gly-X1-X2 triplets flanking the interruption are atypical. Studies on peptide models indicate the degree of destabilization is much greater when Pro is in the interruption, GP, than when hydrophobic residues (GF, GY) are present, and a rigid Gly-Pro-Hyp tripeptide adjacent to the interruption leads to greater destabilization than a flexible Gly-Ala-Ala sequence. Modeling based on NMR data indicates the Phe residue within a GF interruption is located on the outside of the triple helix. The G1G interruptions resemble a previously studied collagen interruption GPOGAAVMGPO, designated G4G-type, in that both are destabilizing, but allow continuation of rod-like triple helices and maintenance of the single residue stagger throughout the imperfection, with a loss of axial register of the superhelix on both sides. Both kinds of interruptions result in a highly localized perturbation in hydrogen bonding and dihedral angles, but the hydrophobic residue of a G4G interruption packs near the central axis of the superhelix, while the hydrophobic residue of a G1G interruption is located on the triple-helix surface. The different structural consequences of G1G and G4G interruptions in the repeating tripeptide sequence pattern suggest a physical basis for their differential susceptibility to matrix metalloproteinases in type X collagen.

  5. Effect of diamond bur cutting efficacy on dentin bond strengths of different bonding systems

    Directory of Open Access Journals (Sweden)

    Shirani F.

    2009-03-01

    Full Text Available "nBackground and Aim: As composite-dentin bond strength is affected by cavity preparation and the bond strength of composite resin to new and used bur prepared dentin has not yet been evaluated, this study evaluated the effects of cutting dentin with different cutting efficacy (new and used of burs on composite-dentin shear bond strength using self-etching primer bonding system and total etching bonding system. "nMaterials and Methods: Sixty caries free human 3rd molar were sectioned in occlosal surface to expose dentin, then polished with silicon carbide paper and randomly divided into four groups. Each group was prepared in a depth of 0.5mm of dentin, using new diamond bur, or used diamond bur. To change into a used bur, each new rough diamond bur had to work on bovine enamel for 30 minutes, under a load of 150g. Then, each group was bonded, using a total etch adhesive (single Bond or a self etch adhesive (clearfil SE Bond So there were 4 groups : 1-SE Bond, New bur; 2-SE Bond , used bur; 3-Single Bond , New bur ; 4-Single Bond, used bur. Similar composite capsules(Filtek Z250 were bonded to dentin surface and cured. specimens were stored in physiologic saline for 48h at 370 c , then put under shearing load to define composite - dentin shear bond strength. Results were interpreted via statistical analysis (T-test & two - way variance. "nResults: Shear bond strength of each group was as follows: 1-(27.3Mpa, 2-(33.5Mpa, 3-(16.9Mpa 4-(19.3Mpa. Statistical analysis proved that shear bond strength of used diamond bur prepared groups (2,4 was more than new diamond bur prepared ones (1,3. This statistical difference, specially, was seen between SE Bond groups (1,2 but not between single Bond groups (3,4. Also, shear bond strength of (SE Bond bonded groups (1,2 were more significantly than (single Bond bonded ones (3,4. "nConclusion: This study show that Bur cutting efficiency influences composite - dentin shear bond strength especially when the

  6. Hydrogen Bonding to Alkanes: Computational Evidence

    DEFF Research Database (Denmark)

    Hammerum, Steen; Olesen, Solveig Gaarn

    2009-01-01

    The structural, vibrational, and energetic properties of adducts of alkanes and strong cationic proton donors were studied with composite ab initio calculations. Hydrogen bonding in [D-H+ H-alkyl] adducts contributes to a significant degree to the interactions between the two components, which...... is substantiated by NBO and AIM results. The hydrogen bonds manifest themselves in the same manner as conventional hydrogen bonds, D-H bond elongation, D-H vibrational stretching frequency red shift and intensity increase, and adduct stabilization. The alkane adducts also exhibit elongation of the C-H bonds...

  7. Statistical thermodynamics of the collagen triple-helix/coil transition. Free energies for amino acid substitutions within the triple-helix.

    Science.gov (United States)

    Doig, Andrew J

    2008-11-27

    Collagen sequences frequently deviate from the most thermally stable (Gly-Pro-Hyp)(n) pattern, with many mutations causing osteogenesis imperfecta (or "brittle bone disease"). The effects of collagen mutations have been studied in short peptides. The analysis of this work is problematic, however, as triple-helices fray from their ends, making the coil/triple-helix equilibrium non-two-state. Here, I develop a statistical thermodynamic model to handle this equilibrium that is applicable to peptides that follow the (G-X-Y)(n) pattern, where Gly is present at every third position and where all three chains are identical. Parameters for substitutions at each position are included, as well as a penalty for initiating triple-helix formation. The model is applied to equilibrium experimental data at 37 degrees C to show that the extension of a triple-helix by a three residue unit stabilizes the triple-helix by 0.76 kcal/mol for Gly-Pro-Hyp and 0.33 kcal/mol for Gly-Pro-Pro. The replacement of Hyp by Arg, Asp, or Trp destabilizes the triple-helix by 1.5, 2.4, and 2.9 kcal/mol, respectively, where the substitution is present once in each chain. The model can thus be used to quantitatively interpret data on collagen peptides, giving free energies that can help rationalize mutations that affect collagen stability, and to design new collagen sequences.

  8. Von Neumann Regularity and Quadratic Conorms in JB*-triples and C*-algebras

    Institute of Scientific and Technical Information of China (English)

    Mar(I)a BURGOS; El Amin KAIDI; Antonio Morales CAMPOY; Antonio M. PERALTA; Maribel RAM(I)REZ

    2008-01-01

    We revise the notion of von Neumann regularity in JB*-triples by finding a new character-isationin terms of the range of the quadratic operator Q(a). We introduce the quadratic conorm of anelement a in a JB*-triple as the minimum reduced modulus of the mapping Q(a). It is shown that thequadratic conorm of a coincides with the infimum of the squares of the points in the triple spectrumof a. It is established that a contractive bijection between JBW*-triples is a triple isomorphism if, andonly if, it preserves quadratic conorms. The continuity of the quadratic conorm and the generalizedinverse are discussed. Some applications to C*-algebras and von Neumann algebras are also studied.

  9. Diffusion bonding of copper to niobium

    Science.gov (United States)

    Wagner, Adrian R.

    Processes used to join metal to ceramic at low temperatures have proven to be inefficient because multiple brazing cycles with different brazing temperatures and braze filler metals are required. Even though this is reproducible and robust, it is not ideal due to the manufacturing time and cost associated with multiple brazing cycles. A more efficient and cost effective process is to utilize the diffusion bonding technique to join different metallic layers prior to joining the entire ceramic assembly in one brazing cycle. In this study, the diffusion bonding of copper to niobium was examined. To the author's knowledge, the diffusion bonding of Cu to Nb has not been researched, and the diffusion of Cu into Nb or Nb into Cu has not been observed. A series of diffusion bonding experiments were conducted to determine the optimal bonding time, temperature, and pressure for the Cu-Nb system. The diffusion bonded samples were evaluated using mechanical testing and microscopy. Results from characterization indicate that diffusion of Nb into Cu occurs, and a robust bond with no interfacial voids is formed using different combinations of bonding parameters. The diffusion of Nb into Cu and with failure occurring outside the diffusion bonded region during all mechanical testing indicate that Cu can be bonded to Nb via the diffusion bonding technique.

  10. Bonding PMMA microfluidics using commercial microwave ovens

    Science.gov (United States)

    Toossi, A.; Moghadas, H.; Daneshmand, M.; Sameoto, D.

    2015-08-01

    In this paper, a novel low-cost, rapid substrate-bonding technique is successfully applied to polymethyl methacrylate (PMMA) microfluidics bonding for the first time. This technique uses a thin intermediate metallic microwave susceptor layer at the interface of the bonding site (microchannels) which produces localized heating required for bonding during microwave irradiation. The metallic susceptor pattern is designed using a multiphysics simulation model developed in ANSYS Multiphysics software (high-frequency structural simulation (HFSS) coupled with ANSYS-Thermal). In our experiments, the required microwave energy for bonding is delivered using a relatively inexpensive, widely accessible commercial microwave oven. Using this technique, simple PMMA microfluidics prototypes are successfully bonded and sealed in less than 35 seconds with a minimum measured bond strength of 1.375 MPa.

  11. Liquidity in Government versus Covered Bond Markets

    DEFF Research Database (Denmark)

    Dick-Nielsen, Jens; Gyntelberg, Jacob; Sangill, Thomas

    We present findings on the secondary market liquidity of government and covered bonds in Denmark before, during and after the 2008 financial crisis. The analysis focuses on wholesale trading in the two markets and is based on a complete transaction level dataset covering November 2007 until end...... 2011. Overall, our findings suggest that Danish benchmark covered bonds by and large are as liquid as Danish government bonds - including in periods of market stress. Before the financial crisis of 2008, government bonds were slightly more liquid than covered bonds. During the crisis, trading continued...... in both markets but the government bond market experienced a brief but pronounced decline in market liquidity while liquidity in the covered bond market was more robust - partly reflective of a number of events as well as policy measures introduced in the autumn of 2008. After the crisis, liquidity...

  12. Cα-H···O=C hydrogen bonds contribute to the specificity of RGD cell-adhesion interactions

    Directory of Open Access Journals (Sweden)

    Humphries Martin J

    2005-02-01

    Full Text Available Abstract Background The Arg-Gly-Asp (RGD cell adhesion sequence occurs in several extracellular matrix molecules known to interact with integrin cell-surface receptors. Recently published crystal structures of the extracellular regions of two integrins in complex with peptides containing or mimicking the RGD sequence have identified the Arg and Asp residues as key specificity determinants for integrin recognition, through hydrogen bonding and metal coordination interactions. The central Gly residue also appears to be in close contact with the integrin surface in these structures. Results When hydrogen atoms are modelled on the central Gly residue with standard stereochemistry, the interaction between this residue and a carbonyl group in the integrin surface shows all the hallmarks of Cα-H···O=C hydrogen bonding, as seen in the collagen triple helix and in many crystal structures of small organic molecules. Moreover, molecular dynamic simulations of the docking of RGD-containing fragments on integrin surfaces support the occurrence of these interactions. There appears to be an array of four weak and conventional hydrogen bonds lining up the RGD residues with main chain carbonyl groups in the integrin surface. Conclusions The occurrence of weak Cα-H···O=C hydrogen bonds in the RGD-integrin interaction highlights the importance of the conserved Gly residue in the RGD motif and its contribution to integrin-ligand binding specificity. Our analysis shows how weak hydrogen bonds may also play important biological roles by contributing to the specificity of macromolecular recognition.

  13. Hückel-Hubbard-Ohno modeling of π-bonds in ethene and ethyne with application to trans-polyacetylene

    Science.gov (United States)

    Timár, Máté; Barcza, Gergely; Gebhard, Florian; Veis, Libor; Legeza, Örs

    Quantum chemistry calculations provide the potential energy between two carbon atoms in ethane (H$_3$C$-$CH$_3$), ethene (H$_2$C$=$CH$_2$), and ethyne (HC$\\equiv$CH) as a function of the atomic distance. Based on the energy function for the $\\sigma$-bond in ethane, $V_{\\sigma}(r)$, we use the H\\"uckel model with Hubbard--Ohno interaction for the $\\pi$~electrons to describe the energies $V_{\\sigma\\pi}(r)$ and $V_{\\sigma\\pi\\pi}(r)$ for the $\\sigma\\pi$ double bond in ethene and the $\\sigma\\pi\\pi$ triple bond in ethyne, respectively. The fit of the force functions shows that the Peierls coupling can be estimated with some precision whereas the Hubbard-Ohno parameters are insignificant at the distances under consideration. We apply the H\\"uckel-Hubbard-Ohno model to describe the bond lengths and the energies of elementary electronic excitations of trans-polyacetylene, (CH)$_n$, and adjust the $\\sigma$-bond potential for conjugated polymers.

  14. Bump bonding of pixel systems

    Energy Technology Data Exchange (ETDEWEB)

    Lozano, M. E-mail: manuel.lozano@cnm.es; Cabruja, E.; Collado, A.; Santander, J.; Ullan, M

    2001-11-01

    A pixel detector consists of an array of radiation sensing elements which is connected to an electronic read-out unit. Many different ways of making this connection between these two different devices are currently being used or considered to be used in the next future. Bonding techniques such as flip chip technology can present real advantages because they allow very fine pitch and a high number of I/Os. This paper presents a review of the different flip chip technologies available and their suitability for manufacturing pixel detectors. The particular problems concerning testing of pixel detectors and thermal issues related to them are pointed out.

  15. Bonded and Stitched Composite Structure

    Science.gov (United States)

    Zalewski, Bart F. (Inventor); Dial, William B. (Inventor)

    2014-01-01

    A method of forming a composite structure can include providing a plurality of composite panels of material, each composite panel having a plurality of holes extending through the panel. An adhesive layer is applied to each composite panel and a adjoining layer is applied over the adhesive layer. The method also includes stitching the composite panels, adhesive layer, and adjoining layer together by passing a length of a flexible connecting element into the plurality of holes in the composite panels of material. At least the adhesive layer is cured to bond the composite panels together and thereby form the composite structure.

  16. Bump bonding of pixel systems

    CERN Document Server

    Lozano, M; Collado, A; Santander, J; Ullán, M

    2001-01-01

    A pixel detector consists of an array of radiation sensing elements which is connected to an electronic read-out unit. Many different ways of making this connection between these two different devices are currently being used or considered to be used in the next future. Bonding techniques such as flip chip technology can present real advantages because they allow very fine pitch and a high number of I/Os. This paper presents a review of the different flip chip technologies available and their suitability for manufacturing pixel detectors. The particular problems concerning testing of pixel detectors and thermal issues related to them are pointed out.

  17. Bonds and bands in semiconductors

    CERN Document Server

    Phillips, Jim

    2009-01-01

    This classic work on the basic chemistry and solid state physics of semiconducting materials is now updated and improved with new chapters on crystalline and amorphous semiconductors. Written by two of the world's pioneering materials scientists in the development of semiconductors, this work offers in a single-volume an authoritative treatment for the learning and understanding of what makes perhaps the world's most important engineered materials actually work. Readers will find: --' The essential principles of chemical bonding, electron energy bands and their relationship to conductive and s

  18. Actor bonds after relationship dissolution

    DEFF Research Database (Denmark)

    Skaates, Maria Anne

    2000-01-01

    Most of the presented papers at the 1st NoRD Workshop can be classified as belonging to the business marketing approach to relationship dissolution. Two papers were conceptual, and the remaining six were empirical studies. The first conceptual study by Skaates (2000) focuses on the nature...... of the actor bonds that remain after a business relationship has ended. The study suggests that an interdisciplinary approach would provide a richer understanding of the phenomenon; this could be achieved by using e.g. Bourdieu's sociological concepts in dissolution research....

  19. 27 CFR 19.956 - Amount of bond.

    Science.gov (United States)

    2010-04-01

    ... of bond. The penal sum of the bond is based on the total quantity of distilled spirits to be produced... increased, and the bond is not in the maximum penal sum, a new or strengthening bond shall be obtained....

  20. A triple quantum dot based nano-electromechanical memory device

    Energy Technology Data Exchange (ETDEWEB)

    Pozner, R.; Lifshitz, E. [Schulich Faculty of Chemistry, Technion-Israel Institute of Technology, Haifa 32000 (Israel); Solid State Institute, Technion-Israel Institute of Technology, Haifa 32000 (Israel); Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 32000 (Israel); Peskin, U., E-mail: uri@tx.technion.ac.il [Schulich Faculty of Chemistry, Technion-Israel Institute of Technology, Haifa 32000 (Israel); Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 32000 (Israel); Lise Meitner Center for Computational Quantum Chemistry, Technion-Israel Institute of Technology, Haifa 32000 (Israel)

    2015-09-14

    Colloidal quantum dots (CQDs) are free-standing nano-structures with chemically tunable electronic properties. This tunability offers intriguing possibilities for nano-electromechanical devices. In this work, we consider a nano-electromechanical nonvolatile memory (NVM) device incorporating a triple quantum dot (TQD) cluster. The device operation is based on a bias induced motion of a floating quantum dot (FQD) located between two bound quantum dots (BQDs). The mechanical motion is used for switching between two stable states, “ON” and “OFF” states, where ligand-mediated effective interdot forces between the BQDs and the FQD serve to hold the FQD in each stable position under zero bias. Considering realistic microscopic parameters, our quantum-classical theoretical treatment of the TQD reveals the characteristics of the NVM.

  1. Prisoners of War of the Triple Alliance within Kazakhstan

    Directory of Open Access Journals (Sweden)

    Gulzhaukhar K. Kokebayeva

    2015-03-01

    Full Text Available The work studies the problem of the detention of prisoners of war of the Triple Alliance in the camps, located within Kazakhstan. During the first months of war, the Russian authorities treated the prisoners of war in accordance with ‘Convention on the Treatment of the Prisoners of War’, approved by the Emperor of Russia. The content of this document corresponded to the Hague Convention with Respect to the Laws and Customs of War on Land. The major areas of the detention of prisoners of war were Turkestan and Omsk Military Okrug, combining all military institutions of the Steppe Governorate General, including the ones of North-Eastern and Central Kazakhstan. The source base of the research is the materials of Kazakhstan and German archives, the recollections of the former prisoners of war and the published collections of documents and materials.

  2. Structure-property-function relationships in triple helical collagen hydrogels

    CERN Document Server

    Tronci, Giuseppe; Russell, Stephen J; Wood, David J

    2012-01-01

    In order to establish defined biomimetic systems, type I collagen was functionalised with 1,3-Phenylenediacetic acid (Ph) as aromatic, bifunctional segment. Following investigation on molecular organization and macroscopic properties, material functionalities, i.e. degradability and bioactivity, were addressed, aiming at elucidating the potential of this collagen system as mineralization template. Functionalised collagen hydrogels demonstrated a preserved triple helix conformation. Decreased swelling ratio and increased thermo-mechanical properties were observed in comparison to state-of-the-art carbodiimide (EDC)-crosslinked collagen controls. Ph-crosslinked samples displayed no optical damage and only a slight mass decrease (~ 4 wt.-%) following 1-week incubation in simulated body fluid (SBF), while nearly 50 wt.-% degradation was observed in EDC-crosslinked collagen. SEM/EDS revealed amorphous mineral deposition, whereby increased calcium phosphate ratio was suggested in hydrogels with increased Ph content...

  3. An overview of triple negative breast cancer for surgical oncologists.

    Science.gov (United States)

    Sharma, Shiva; Barry, Mitchel; Gallagher, David J; Kell, Malcolm; Sacchini, Virgilio

    2015-09-01

    Triple negative breast cancers (TNBCs) represent a distinct subgroup of breast cancers with an immunohistochemical phenotype that is negative for oestrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER-2). The aim of this article is to provide a broad overview of recent developments in the diagnosis and management of TNBC for surgical oncologists. This overview discusses the subtypes of TNBC and the relationship between this type of breast cancer and the BRCA1 gene. In addition, the article explores recent advances in the treatment of TNBC from a surgical, radiation, and medical oncology point of view. Lastly, evolving therapeutic strategies that have potential to enhance outcomes for patients with TNBC are also discussed.

  4. Triple inverter pierce oscillator circuit suitable for CMOS

    Science.gov (United States)

    Wessendorf; Kurt O.

    2007-02-27

    An oscillator circuit is disclosed which can be formed using discrete field-effect transistors (FETs), or as a complementary metal-oxide-semiconductor (CMOS) integrated circuit. The oscillator circuit utilizes a Pierce oscillator design with three inverter stages connected in series. A feedback resistor provided in a feedback loop about a second inverter stage provides an almost ideal inverting transconductance thereby allowing high-Q operation at the resonator-controlled frequency while suppressing a parasitic oscillation frequency that is inherent in a Pierce configuration using a "standard" triple inverter for the sustaining amplifier. The oscillator circuit, which operates in a range of 10 50 MHz, has applications for use as a clock in a microprocessor and can also be used for sensor applications.

  5. Triple differential cross sections of magnesium in doubly symmetric geometry

    Science.gov (United States)

    S, Y. Sun; X, Y. Miao; Xiang-Fu, Jia

    2016-01-01

    A dynamically screened three-Coulomb-wave (DS3C) method is applied to study the single ionization of magnesium by electron impact. Triple differential cross sections (TDCS) are calculated in doubly symmetric geometry at incident energies of 13.65, 17.65, 22.65, 27.65, 37.65, 47.65, 57.65, and 67.65 eV. Comparisons are made with experimental data and theoretical predictions from a three-Coulomb-wave function (3C) approach and distorted-wave Born approximation (DWBA). The overall agreement between the predictions of the DS3C model and the DWBA approach with the experimental data is satisfactory. Project supported by the National Natural Science Foundation of China (Grant No. 11274215).

  6. Distinct microbiological signatures associated with triple negative breast cancer.

    Science.gov (United States)

    Banerjee, Sagarika; Wei, Zhi; Tan, Fei; Peck, Kristen N; Shih, Natalie; Feldman, Michael; Rebbeck, Timothy R; Alwine, James C; Robertson, Erle S

    2015-10-15

    Infectious agents are the third highest human cancer risk factor and may have a greater role in the origin and/or progression of cancers, and related pathogenesis. Thus, knowing the specific viruses and microbial agents associated with a cancer type may provide insights into cause, diagnosis and treatment. We utilized a pan-pathogen array technology to identify the microbial signatures associated with triple negative breast cancer (TNBC). This technology detects low copy number and fragmented genomes extracted from formalin-fixed paraffin embedded archival tissues. The results, validated by PCR and sequencing, define a microbial signature present in TNBC tissue which was underrepresented in normal tissue. Hierarchical clustering analysis displayed two broad microbial signatures, one prevalent in bacteria and parasites and one prevalent in viruses. These signatures demonstrate a new paradigm in our understanding of the link between microorganisms and cancer, as causative or commensal in the tumor microenvironment and provide new diagnostic potential.

  7. Triple-Vessel Percutaneous Coronary Revascularization In Situs Inversus Dextrocardia

    Directory of Open Access Journals (Sweden)

    Nikolaos Kakouros

    2010-01-01

    Full Text Available Dextrocardia with situs inversus occurs in approximately one in 10,000 individuals of whom 20% have primary ciliary dyskinesia inherited as an autosomal recessive trait. These patients have a high incidence of congenital cardiac disease but their risk of coronary artery disease is similar to that of the general population. We report what is, to our knowledge, the first case of total triple-vessel coronary revascularization by percutaneous stent implantation in a 79-year-old woman with situs inversus dextrocardia. We describe the successful use of standard diagnostic and interventional guide catheters with counter rotation and transversely inversed image acquisition techniques. The case also highlights that the right precordial pain may represent cardiac ischemia in this population.

  8. Recovery by triple junction motion in heavily deformed metals

    DEFF Research Database (Denmark)

    Yu, Tianbo; Hansen, Niels; Huang, Xiaoxu

    2015-01-01

    A number of processes may occur during recovery, which reduce the stored energy and coarsen the structure, paving the way for the nucleation of recrystallization. In this review, recovery is discussed based on the initial deformed structure. Recovery in samples deformed to low-to-medium strains...... is briefly considered, whereas recovery in samples deformed to much higher strains is discussed in more detail. An example is Al, where a new and important recovery mechanism is triple junction motion, which can remove thin lamellae and consequently increase the thickness of neighbouring lamellae....... This recovery mechanism therefore coarsens the structure and causes a gradual transition from a lamellar to a near equiaxed structure preceding recrystallization. This mechanism is discussed in conjunction with structural pinning, which stabilizes the coarsening microstructure, thereby balancing the forces...

  9. DEINDUSTRIALISASI SEBUAH ANCAMAN KEGAGALAN TRIPLE TRACK STRATEGY PEMBANGUNAN DI INDONESIA

    Directory of Open Access Journals (Sweden)

    P. Eko Prasetyo

    2015-12-01

    Full Text Available SBY government work effort through the triple-track strategy namely pro-growth, pro jobs and pro-poor developments will be doomed to fail because of a deindustrialization inIndonesia. The phenomenon of deindustrialization is characterized by the continued decline of industrial contribution mainly manufacture industrial sektor to the value added, employment, exports and contribution to GDP growth, would obviously be a serious threat to the government in its efforts to achieve economic growth to reduce unemployment and poverty. Industrial sektor at this time was no longer regarded as a leading sektor in the national and regional development, so that if eagerly handled will have a negative impact more and could threaten the stability of the economic development of Indonesia.

  10. Polygonal triple (Kotz) osteotomy (over 10 years experience).

    Science.gov (United States)

    Sen, Cengiz; Gunes, Taner; Erdem, Mehmet; Ozger, Harzem; Tozun, I Remzi

    2007-06-01

    We evaluated the results of polygonal triple (Kotz) osteotomy for the treatment of acetabular dysplasia over 10 years. This study included 31 hips of 27 patients who had the Kotz osteotomy for acetabular dysplasia. The mean age was 21.5 years. We performed the original Kotz osteotomy for the first 22 hips (group I), while the modified Kotz osteotomy through an intra-pelvic approach without damage to the abductor muscle was applied for the last 9 hips (group II). Patients were evaluated by clinically and radiologically. The average follow-up was 106 months in group I, and 18 months in group II. The Trendelenburg gait was unchanged for four patients in group I and for one patient in group II. The Harris Hip Score improved in all patients postoperatively. Radiographic assesment showed improvement in both groups in terms of the angle of CE, VCE, and Sharp postoperatively(PTrendelenburg gait compared to the original Kotz osteotomy.

  11. Application of triple potential step amperometry method for quantitative electroanalysis

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A novel quantitative electroanalysis method, triple potential step amperometry (TPSA), was developed and explained with an example of nitrobenzene analyzing in water. The selectivity of TPSA was improved by controlling the potential step within a narrow interval and using enzyme-modified electrode, the narrow potential step makes the method avoid most interferents, and enzyme-modified electrode can enhance the response of target substance selectively. The peak area was investigated for quantitative calibration, such as nitrobenzene concentration showing a linear relation with the peak area, with the correlation coefficients being 0.9995. The t-test and F-test were applied to evaluating the reliability of TPSA, the results showed that there was no evidence of systematic error for TPSA, and the method was of no significant difference from CV. The merit of fast detecting and few potential changing times make the TPSA suitably applicable to low-cost automatic monitoring equipments.

  12. Triple-stimulation technique in multifocal neuropathy with conduction block.

    Science.gov (United States)

    Deroide, Nicolas; Uzenot, David; Verschueren, Annie; Azulay, Jean-Philippe; Pouget, Jean; Attarian, Shahram

    2007-05-01

    In patients with multifocal neuropathy with conduction block (CB), CBs located between the root and Erb's point are not detected in nerve conduction studies. We therefore examined whether the triple-stimulation technique (TST) might provide a useful means of detecting CB proximal to Erb's point. Clinical assessments, extensive nerve conduction studies (NCS), conventional transcranial magnetic stimulation, and TST were performed on 10 patients with multifocal motor neuropathy with CB (MMNCB) and 6 patients with Lewis-Sumner syndrome. Conduction blocks located proximal to Erb's point were detected in 9 patients. Of the CBs, 58% were associated with muscle weakness. The use of TST to detect proximal CB improved the sensitivity of the American Association of Neuromuscular and Electrodiagnostic Medicine criteria for definite or probable MMNCB from 60% to 90%. Thus, the TST is a useful means for detection of proximal CB and gives NCS considerable additional diagnostic power.

  13. Tetraphenylporphyrin as a protein label for triple detection analytical systems

    Directory of Open Access Journals (Sweden)

    Kamila Konopińska

    2015-12-01

    Full Text Available Porphyrins and metalloporphyrins are promising new protein labels that can be detected using multiple techniques; improving the reliability of the analysis and broadening the range of the linear response. Here, we investigate the potential of 5,10,15,20-tetraphenyl-21H,23H-porphyrin (Tpp as a hybrid protein label. The electrochemical and optical properties of porphyrin conjugated with bovine serum albumin (BSA, chicken egg albumin (CEA and immunoglobulin G (IgG were determined and optimal conditions for Tpp-protein conjugation established. Model conjugates of carboxylated Tpp with BSA and short peptides were characterized using differential pulse voltammetry, UV–Vis spectrophotometry and spectrofluorimetry. These results reveal that Tpp is a promising molecule to be used in a triple detection protein labelling system.

  14. Single-, Dual- and Triple-band Frequency Reconfigurable Antenna

    Directory of Open Access Journals (Sweden)

    I. H. Idris

    2014-09-01

    Full Text Available The paper presents a frequency reconfigurable slot dipole antenna. The antenna is capable of being switched between single-band, dual-band or triple-band operation. The antenna incorporates three pairs of pin-diodes which are located within the dipole arms. The antenna was designed to operate at 2.4 GHz, 3.5 GHz and 5.2 GHz using the aid of CST Microwave Studio. The average measured gains are 1.54, 2.92 and 1.89 dBi for low, mid and high band respectively. A prototype was then constructed in order to verify the performance of the device. A good level of agreement was observed between simulation and measurement.

  15. Initiation of triple therapy maintenance treatment among patients with COPD in the US

    Directory of Open Access Journals (Sweden)

    Simeone JC

    2016-12-01

    Full Text Available Jason C Simeone,1 Rakesh Luthra,2 Shuchita Kaila,2 Xiaoyun Pan,1 Tarun D Bhagnani,1 Jieruo Liu,1 Teresa K Wilcox1 1Real-World Evidence, Evidera, Waltham, MA, 2HEOR Value Demonstration Team, Boehringer Ingelheim Pharmaceuticals, Inc., Ridgefield, CT, USA Background: The Global Initiative for Chronic Obstructive Lung Disease (GOLD recommends triple therapy (long-acting muscarinic receptor antagonists, long-acting beta-2 agonists, and inhaled corticosteroids for patients with only the most severe COPD. Data on the proportion of COPD patients on triple therapy and their characteristics are sparse and dated. Objective 1 of this study was to estimate the proportion of all, and all treated, COPD patients receiving triple therapy. Objective 2 was to characterize those on triple therapy and assess the concordance of triple therapy use with GOLD guidelines. Patients and methods: This retrospective study used claims from the IMS PharMetrics Plus database from 2009 to 2013. Cohort 1 was selected to assess Objective 1 only; descriptive analyses were conducted in Cohort 2 to answer Objective 2. A validated claims-based algorithm and severity and frequency of exacerbations were used as proxies for COPD severity. Results: Of all 199,678 patients with COPD in Cohort 1, 7.5% received triple therapy after diagnosis, and 25.5% of all treated patients received triple therapy. In Cohort 2, 30,493 COPD patients (mean age =64.7 years who initiated triple therapy were identified. Using the claims-based algorithm, 34.5% of Cohort 2 patients were classified as having mild disease (GOLD 1, 40.8% moderate (GOLD 2, 22.5% severe (GOLD 3, and 2.3% very severe (GOLD 4. Using exacerbation severity and frequency, 60.6% of patients were classified as GOLD 1/2 and 39.4% as GOLD 3/4. Conclusion: In this large US claims database study, one-quarter of all treated COPD patients received triple therapy. Although triple therapy is recommended for the most severe COPD patients

  16. Multilayer Antireflection Coating for Triple Junction Solar Cells

    Institute of Scientific and Technical Information of China (English)

    ZHAN Feng; WANG Hai-Li; HE Ji-Fang; WANG Juan; HUANG She-Song; NI Hai-Qiao; NIU Zhi-Chuan

    2011-01-01

    @@ According to the theory of optical films, we simulate the reflectivity of antireflection coatings(ARCS)for solar cells of Gao.51no.5P/GaAs/Ge based on an optical transfer matrix.In order to provide sufficient consideration of the refractive index dispersion effect of multilayer ARCS, we use multi-dimensional matrix data for reliable simulation.After the reflection curves are obtained, the effective average reflectance Re is introduced to optimize the film system by minimizing Re.Optimization of single layer(A1203), double layer(MgF2/ZnS)and triple layer(MgF2/A12O3/ZnS)ARCS is realized by using this method for space and terrestrial applications.Effects of these ARCS are compared after optimization.These theoretical parameters can be used to guide experiments.%According to the theory of optical films, we simulate the reflectivity of antireflection coatings (ARCs) for solar cells of Ga0.5In0.5P/GaAs/Ge based on an optical transfer matrix. In order to provide sufficient consideration of the refractive index dispersion effect of multilayer ARCs, we use multi-dimensional matrix data for reliable simulation. After the reflection curves are obtained, the effective average reflectance Re is introduced to optimize the film system by minimizing Re. Optimization of single layer (Al2O3), double layer (MgF2/ZnS) and triple layer (MgF2/Al2O3/ZnS) ARCs is realized by using this method for space and terrestrial applications. Effects of these ARCs are compared after optimization. These theoretical parameters can be used to guide experiments.

  17. Triple-negative breast cancer: treatment challenges and solutions

    Directory of Open Access Journals (Sweden)

    Collignon J

    2016-05-01

    Full Text Available Joëlle Collignon,1 Laurence Lousberg,1 Hélène Schroeder,1 Guy Jerusalem,1,21Medical Oncology Department, CHU Sart Tilman Liege, Domaine Universitaire du Sart Tilman, Liege, Belgium; 2University of Liege, Liege, Belgium Abstract: Triple-negative breast cancers (TNBCs are defined by the absence of estrogen and progesterone receptors and the absence of HER2 overexpression. These cancers represent a heterogeneous breast cancer subtype with a poor prognosis. Few systemic treatment options exist besides the use of chemotherapy (CT. The heterogeneity of the disease has limited the successful development of targeted therapy in unselected patient populations. Currently, there are no approved targeted therapies for TNBC. However, intense research is ongoing to identify specific targets and develop additional and better systemic treatment options. Standard adjuvant and neoadjuvant regimens include anthracyclines, cyclophosphamide, and taxanes. Platinum-based CT has been proposed as another CT option of interest in TNBC. We review the role of this therapy in general, and particularly in patients carrying BRCA germ-line mutations. Available data concerning the role of platinum-based CT in TNBC were acquired primarily in the neoadjuvant setting. The routine use of platinum-based CT is not yet recommended by available guidelines. Many studies have reported the molecular characterization of TNBCs. Several actionable targets have been identified. Novel therapeutic strategies are currently being tested in clinical trials based on promising results observed in preclinical studies. These targets include androgen receptor, EGFR, PARP, FGFR, and the angiogenic pathway. We review the recent data on experimental drugs in this field. We also discuss the recent data concerning immunologic checkpoint inhibitors. Keywords: triple-negative breast cancer, molecular subtype, platinum-based chemotherapy, targeted therapy, androgen receptor, BRCA1/2 mutation

  18. Amor: Investigating The Triple Asteroid System 2001 SN263

    Science.gov (United States)

    Jones, T.; Bellerose, Julie; Lee, P.; Prettyman, T.; Lawrence, D.; Smith, P.; Gaffey, M.; Nolan, M.; Goldsten, J.; Thomas, P.; Veverka, J.; Farquhar, R.; Heldmann, J.; Reddy, V.; Williams, B.; Chartres, J.; DeRosee, R.; Dunham, D.

    2010-10-01

    The Amor mission will rendezvous and land at the triple Near-Earth Asteroid system (153591) 2001 SN263 and execute detailed, in-situ science investigations. The spacecraft reaches 2001 SN263 by using a two-year ΔVEGA (ΔV-Earth Gravity Assist) trajectory with a relatively low launch C3 of 33.5 km2/s2. Rendezvous will enable reconnaissance activities including global and regional imaging, shape modeling, system dynamics, and compositional mapping. After landing, Amor will conduct in-situ imaging (panoramic to microscopic scale) and compositional measurements to include elemental abundance. The main objectives are to 1) establish in-situ the long-hypothesized link between C-type asteroids and the primitive carbonaceous chondrite (CC) meteorites, 2) investigate the nature, origin and evolution of C-type asteroids, and 3) investigate the origin and evolution of a multiple asteroid system. The mission also addresses the distribution of volatiles and organic materials, impact hazards, and resources for future exploration. Amor is managed by NASA Ames Research Center in partnership with Orbital Sciences, KinetX, MDA, and Draper with heritage instruments provided by Ball Aerospace, JHU/APL, and Firestar Engineering. The science team brings experience from NEAR, Hayabusa, Deep Impact, Dawn, LCROSS, Kepler, and Mars missions. In this paper, we describe the science, mission design, and main operational challenges of performing in-situ science at this triple asteroid system. Challenges include landing on the asteroid components, thermal environment, short day-night cycles, and the operation of deployed instruments in a low gravity (10^-5 g) environment.

  19. Vascular characterisation of triple negative breast carcinomas using dynamic MRI

    Energy Technology Data Exchange (ETDEWEB)

    Li, Sonia P.; Beresford, Mark J.; Ah-See, Mei-Lin W.; Makris, Andreas [Mount Vernon Cancer Centre, Academic Oncology Unit, Northwood, Middlesex (United Kingdom); Padhani, Anwar R.; Taylor, N.J.; Stirling, J.J. [Mount Vernon Hospital, Paul Strickland Scanner Centre, Northwood, Middlesex (United Kingdom); D' Arcy, James A.; Collins, David J. [Royal Marsden NHS Foundation Trust and Institute of Cancer Research, CR UK and EPSRC Cancer Imaging Centre, Sutton, Surrey (United Kingdom)

    2011-07-15

    Triple-negative (ER-/PR-/HER2-) breast carcinomas (TNBC) are aggressive tumours with underexplored imaging features. This study investigates whether their vascular characteristics as assessed by dynamic contrast-enhanced (DCE) and dynamic susceptibility contrast-enhanced (DSC) MRI are distinct from the prognostically more favourable ER+/PR+/HER2- cancers. Patients with primary breast cancer underwent MRI before neoadjuvant chemotherapy and were identified as ER-/PR-/HER2- or ER+/PR+/HER2- from core biopsy specimens. MRI parameters reflecting tissue perfusion, permeability, and extracellular leakage space were measured. Values for inflow transfer constant (K{sup trans}), outflow rate constant (k{sub ep}), leakage space (v{sub e}), area under the gadolinium curve (IAUGC{sub 60}), relative blood volume (rBV) and flow (rBF), and Mean Transit Time (MTT) were compared across receptor status and with known prognostic variables. Thirty seven patients were assessable in total (16 ER-/PR-/HER2-, 21 ER+/PR+/HER2-). Lower v{sub e} (p = 0.001), shorter MTT (p = 0.007) and higher k{sub ep} values (p = 0.044) were observed in TNBC. v{sub e} was lower across all T stages, node-negative (p = 0.004) and low-grade TNBC (p = 0.037). v{sub e} was the best predictor of triple negativity (ROC AUC 0.80). TNBC possess characteristic features on imaging, with lower extracellular space (higher cell density) and higher contrast agent wash-out rate (higher vascular permeability) suggesting a distinctive phenotype detectable by MRI. (orig.)

  20. Triple-negative breast cancer: new perspectives for targeted therapies

    Directory of Open Access Journals (Sweden)

    Tomao F

    2015-01-01

    Full Text Available Federica Tomao,1 Anselmo Papa,2 Eleonora Zaccarelli,2 Luigi Rossi,2 Davide Caruso,2 Marina Minozzi,2 Patrizia Vici,3 Luigi Frati,4 Silverio Tomao21Department of Gynecology and Obstetrics, “Sapienza” University of Rome, Policlinico “Umberto I”, Rome, 2Department of Medico-Surgical Sciences and Biotechnologies, “Sapienza” University of Rome, Oncology Unit, Istituto Chirurgico Ortopedico Traumatologico, Latina, 3Division of Medical Oncology B, Regina Elena National Cancer Institute, Rome, Italy; 4Department of Molecular Medicine, “Sapienza” University of Rome, Policlinico “Umberto I”, Rome, ItalyAbstract: Breast cancer is a heterogeneous disease, encompassing a large number of entities showing different morphological features and having clinical behaviors. It has became apparent that this diversity may be justified by distinct patterns of genetic, epigenetic, and transcriptomic aberrations. The identification of gene-expression microarray-based characteristics has led to the identification of at least five breast cancer subgroups: luminal A, luminal B, normal breast-like, human epidermal growth factor receptor 2, and basal-like. Triple-negative breast cancer is a complex disease diagnosed by immunohistochemistry, and it is characterized by malignant cells not expressing estrogen receptors or progesterone receptors at all, and human epidermal growth factor receptor 2. Along with this knowledge, recent data show that triple-negative breast cancer has specific molecular features that could be possible targets for new biological targeted drugs. The aim of this article is to explore the use of new drugs in this particular setting, which is still associated with poor prognosis and high risk of distant recurrence and death.Keywords: basal-like breast cancer, estrogen–progesterone receptors, gene-expression microarray, human epidermal growth factor receptor 2, chemotherapy, target therapy

  1. Density Functionals of Chemical Bonding

    Directory of Open Access Journals (Sweden)

    Mihai V. Putz

    2008-06-01

    Full Text Available The behavior of electrons in general many-electronic systems throughout the density functionals of energy is reviewed. The basic physico-chemical concepts of density functional theory are employed to highlight the energy role in chemical structure while its extended influence in electronic localization function helps in chemical bonding understanding. In this context the energy functionals accompanied by electronic localization functions may provide a comprehensive description of the global-local levels electronic structures in general and of chemical bonds in special. Becke-Edgecombe and author’s Markovian electronic localization functions are discussed at atomic, molecular and solid state levels. Then, the analytical survey of the main workable kinetic, exchange, and correlation density functionals within local and gradient density approximations is undertaken. The hierarchy of various energy functionals is formulated by employing both the parabolic and statistical correlation degree of them with the electronegativity and chemical hardness indices by means of quantitative structure-property relationship (QSPR analysis for basic atomic and molecular systems.

  2. MICROSTRUCTURE CHARACTERISTICS AT THE BOND INTERFACE

    Institute of Scientific and Technical Information of China (English)

    Li Junhui; Han Lei; Zhong Jue

    2005-01-01

    Lift-off and section characteristics at the interface of thermosonic bond are observed by using scanning electron microscope (KYKY2800) with EDS-test. Results show that the peeling underdeveloped bonds simulate a torus (or doughnut) with an unbonded central region and ridged peripheral region is bonded hardly. Inside roundness at flip chip bonding center are discovered. Bond strength is located between the severely ridged periphery and the non-adhering central area of the bond. For constant force and time, the ridged area of the bond pattern increases when more power is applied. For constant force and power, the ridged location of the bonded region moves closer to the bond center with time. Results of EDS-tests at Au-Al and Au-Ag interfaces show that Kirkendall diffusibility at Au-Ag interface occur and the diffusing speed of Au-atomic is faster than that of Ag,and that intermetallic compounds at Au-A1 interface is generated possibly. And these would be helpful for further research about thermosonic bonding.

  3. Progress in cold roll bonding of metals

    Energy Technology Data Exchange (ETDEWEB)

    Li Long; Nagai, Kotobu; Yin Fuxing [Innovative Materials Engineering Laboratory, National Institute for Materials Science, Tsukuba 305-0047 (Japan)], E-mail: LI.Long@nims.go.jp

    2008-04-01

    Layered composite materials have become an increasingly interesting topic in industrial development. Cold roll bonding (CRB), as a solid phase method of bonding same or different metals by rolling at room temperature, has been widely used in manufacturing large layered composite sheets and foils. In this paper, we provide a brief overview of a technology using layered composite materials produced by CRB and discuss the suitability of this technology in the fabrication of layered composite materials. The effects of process parameters on bonding, mainly including process and surface preparation conditions, have been analyzed. Bonding between two sheets can be realized when deformation reduction reaches a threshold value. However, it is essential to remove surface contamination layers to produce a satisfactory bond in CRB. It has been suggested that the degreasing and then scratch brushing of surfaces create a strong bonding between the layers. Bonding mechanisms, in which the film theory is expressed as the major mechanism in CRB, as well as bonding theoretical models, have also been reviewed. It has also been showed that it is easy for fcc structure metals to bond compared with bcc and hcp structure metals. In addition, hardness on bonding same metals plays an important part in CRB. Applications of composites produced by CRB in industrial fields are briefly reviewed and possible developments of CRB in the future are also described. Corrections were made to the abstract and conclusion of this article on 18 June 2008. The corrected electronic version is identical to the print version. (topical review)

  4. Silver- and gold-mediated nucleobase bonding.

    Science.gov (United States)

    Acioli, Paulo H; Srinivas, Sudha

    2014-08-01

    We report the results of a density functional theory investigation of the bonding of nucleobases mediated by silver and gold atoms in the gas phase. Our calculations use the Becke exchange and Perdew-Wang correlation functional (BPW91) combined with the Stuttgart effective core potentials to represent the valence electrons of gold, silver, and platinum, and the all-electron DGTZVP basis set for C, H, N, and O. This combination was chosen based on tests on the metal atoms and tautomers of adenine, cytosine, and guanine. To establish a benchmark to understand the metal-mediated bonding, we calculated the binding energy of each of the base pairs in their canonical forms. Our calculations show rather strong bonds between the Watson-Crick base pairs when compared with typical values for N-H-N and N-H-O hydrogen bonds. The neutral metal atoms tend to bond near the nitrogen atoms. The effect of the metal atoms on the bonding of nucleobases differs depending on whether or not the metal atoms bond to one of the hydrogen-bonding sites. When the silver or gold atoms bond to a non-hydrogen-bonding site, the effect is a slight enhancement of the cytosine-guanine bonding, but there is almost no effect on the adenine-thymine pairing. The metal atoms can block one of the hydrogen-bonding sites, thus preventing the normal cytosine-guanine and adenine-thymine pairings. We also find that both silver and gold can bond to consecutive guanines in a similar fashion to platinum, albeit with a significantly lower binding energy.

  5. Shear bond strength of ceramic and metallic orthodontic brackets bonded with self-etching primer and conventional bonding adhesives

    Science.gov (United States)

    Arash, Valiollah; Naghipour, Fatemeh; Ravadgar, Mehdi; Karkhah, Ahmad; Barati, Mohammad Saleh

    2017-01-01

    Introduction Adult patients typically require high-quality orthodontic treatment for ceramic brackets, but some clinicians remain concerned about the bond strength of these brackets. Therefore, the aim of this study was to determine the shear bond strength and de-bonding characteristics of metallic and ceramic brackets bonded with two types of bonding agents. Methods In an experimental study done in 2013 in Babol, Iran, 120 extracted human maxillary premolar teeth were randomly divided into four groups as follows: HM group: metallic bracket/conventional bonding agent; SM group: metallic bracket/Transbond self-etching primer; HC group: ceramic bracket/conventional bonding agent; SC group: ceramic bracket/Transbond self-etching primer. Twenty-four hours after thermocycling (1000 cycle, 5 °C–55 °C), the shear bond strength values were measured. The amount of resin remaining on the tooth surface (adhesive remnant index: ARI) was determined under a stereomicroscope. Enamel detachment index was evaluated under a scanning electron microscope. To perform statistical analysis, ANOVA, Kruskal–Wallis, and Tukey post-hoc tests were applied. The level of significance was set at p ceramic brackets. In addition, self-etching primer was able to produce fewer bonds compared with the conventional technique. Many samples showed the bracket-adhesive interface failure or failure inside the adhesive. PMID:28243410

  6. A peptide study of the relationship between the collagen triple-helix and amyloid.

    Science.gov (United States)

    Parmar, Avanish S; Nunes, Ana Monica; Baum, Jean; Brodsky, Barbara

    2012-10-01

    Type XXV collagen, or collagen-like amyloidogenic component, is a component of amyloid plaques, and recent studies suggest this collagen affects amyloid fibril elongation and has a genetic association with Alzheimer's disease. The relationship between the collagen triple helix and amyloid fibrils was investigated by studying peptide models, including a very stable triple helical peptide (Pro-Hyp-Gly)₁₀ , an amyloidogenic peptide GNNQQNY, and a hybrid peptide where the GNNQQNY sequence was incorporated between (GPO)(n) domains. Circular dichroism and nuclear magnetic resonance (NMR) spectroscopy showed the GNNQQNY peptide formed a random coil structure, whereas the hybrid peptide contained a central disordered GNNQQNY region transitioning to triple-helical ends. Light scattering confirmed the GNNQQNY peptide had a high propensity to form amyloid fibrils, whereas amyloidogenesis was delayed in the hybrid peptide. NMR data suggested the triple-helix constraints on the GNNQQNY sequence within the hybrid peptide may disfavor the conformational change necessary for aggregation. Independent addition of a triple-helical peptide to the GNNQQNY peptide under aggregating conditions delayed nucleation and amyloid fibril growth. The inhibition of amyloid nucleation depended on the Gly-Xaa-Yaa sequence and required the triple-helix conformation. The inhibitory effect of the collagen triple-helix on an amyloidogenic sequence, when in the same molecule or when added separately, suggests Type XXV collagen, and possibly other collagens, may play a role in regulating amyloid fibril formation.

  7. Structural insights into the stabilization of MALAT1 noncoding RNA by a bipartite triple helix.

    Science.gov (United States)

    Brown, Jessica A; Bulkley, David; Wang, Jimin; Valenstein, Max L; Yario, Therese A; Steitz, Thomas A; Steitz, Joan A

    2014-07-01

    Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) is a highly abundant nuclear long noncoding RNA that promotes malignancy. A 3'-stem-loop structure is predicted to confer stability by engaging a downstream A-rich tract in a triple helix, similar to the expression and nuclear retention element (ENE) from the KSHV polyadenylated nuclear RNA. The 3.1-Å-resolution crystal structure of the human MALAT1 ENE and A-rich tract reveals a bipartite triple helix containing stacks of five and four U•A-U triples separated by a C+•G-C triplet and C-G doublet, extended by two A-minor interactions. In vivo decay assays indicate that this blunt-ended triple helix, with the 3' nucleotide in a U•A-U triple, inhibits rapid nuclear RNA decay. Interruption of the triple helix by the C-G doublet induces a 'helical reset' that explains why triple-helical stacks longer than six do not occur in nature.

  8. The Nature of the Hydrogen Bond Outline of a Comprehensive Hydrogen Bond Theory

    CERN Document Server

    Gilli, Gastone

    2009-01-01

    Hydrogen bond (H-bond) effects are known: it makes sea water liquid, joins cellulose microfibrils in trees, shapes DNA into genes and polypeptide chains into wool, hair, muscles or enzymes. Its true nature is less known and we may still wonder why O-H...O bond energies range from less than 1 to more than 30 kcal/mol without apparent reason. This H-bond puzzle is re-examined here from its very beginning and presented as an inclusive compilation of experimental H-bond energies andgeometries.New concepts emerge from this analysis: new classes of systematically strong H-bonds (CAHBs and RAHBs: cha

  9. Nondestructive Characterization of Quantitative Bonding Strength at a Bonded Solid-Solid Interface

    Institute of Scientific and Technical Information of China (English)

    CHEN Jian-Jun; ZHANG De; MAO Yi-Wei; CHENG Jian-Chun

    2011-01-01

    @@ We propose a nondestructive method to characterize the quantitative bonding strength at a bonded solid-solid interface by a contact acoustic nonlinearity (CAN)microscope.The principle of the CAN microscope is briefly described.The vibration amplitude of the incident focusing wave at the bonded interface is calculated, the standard bonding strength with a complete bonding state is established by the tension test, and the CAN parameter is calibrated.The quantitative contour of bonding strength at the interface could be obtained.The experimental contours of two samples are also presented.

  10. Temperature effect in thermosonic wire bonding

    Institute of Scientific and Technical Information of China (English)

    WU Yun-xin; LONG Zhi-li; HAN Lei; ZHONG Jue

    2006-01-01

    The temperature effect on bonding strength and ultrasonic transmission in a PZT transducer system was investigated. The results show that, the temperature change influences the material features of the bonding interface, such as elastic modulus, tensile strength of gold ball and Ag substrate, which results in different bonding strengths. Moreover, the temperature change also influences the impedance and dissipative ultrasonic energy in the PZT system. The current signal of PZT transducer was analyzed by join time-frequency analysis, which can reveal the current change in a bonding process more clearly and completely. The analysis shows that the bonding parameters influence mutually. These results can help build some criteria for parameter match and optimization in wire bonding processes.

  11. Thermal Conductance through Sapphire-Sapphire Bonding

    Science.gov (United States)

    Suzuki, T.; Tomaru, T.; Haruyama, T.; Shintomi, T.; Uchinyama, T.; Miyoki, S.; Ohashi, M.; Kuroda, K.

    2003-07-01

    Thermal conductance on sapphire-sapphire bonded interface has been investigated. Two pieces of single crystal sapphire bar with square cross section were bonded together by adhesion free bonding. In two sections of the bar, thermal conductivity was measured between 5 K to 300K. One section contains a bonded interface and the other section measured a thermal conductivity of the sapphire as a reference. No significant thermal resistance due to bonded interface was found from this measurement. Obtained thermal conductivity reaches κ 1 × 104 [W/m·K] in temperature range of T = 20 ˜ 30 K which is a planned operating temperature of a cryogenic mirror of the Large scale Cryogenic Gravitational wave telescope. It looks promising for sapphire bonding technique to improve a heat transfer from a large cryogenic mirror to susp ension wires.

  12. Decomposing European bond and equity volatility

    DEFF Research Database (Denmark)

    Christiansen, Charlotte

    The paper investigates volatility spillover from US and aggregate European asset markets into European national asset markets. A main contribution is that bond and equity volatilities are analyzed simultaneously. A new model belonging to the "volatilityspillover" family is suggested......: The conditional variance of e.g. the unexpected German stock return is divided into separate effects from the contemporaneous idiosyncratic variance of US bonds, US stocks, European bonds, European stocks, German bonds, and German stocks. Significant volatility-spillover effects are found. The national bond...... (stock) volatilities are mainly influenced by bond (stock) effects. Global, regional, and local volatility effects are all important. The introduction of the euro is associated with a structural break....

  13. Imaging Hydrogen Bond in Real Space

    CERN Document Server

    Chen, Xiu; Liu, Lacheng; Liu, Xiaoqing; Cai, Yingxing; Liu, Nianhua; Wang, Li

    2013-01-01

    Hydrogen bond is often assumed to be a purely electrostatic interaction between a electron-deficient hydrogen atom and a region of high electron density. Here, for the first time, we directly image hydrogen bond in real space by room-temperature scanning tunneling microscopy (STM) with the assistance of resonant tunneling effect in double barrier mode. STM observations demonstrate that the C=O:HO hydrogen bonds lifted several angstrom meters above metal surfaces appear shuttle-like features with a significant contrast along the direction connected the oxygen and hydrogen atoms of a single hydrogen bond. The off-center location of the summit and the variance of the appearance height for the hydrogen bond with scanning bias reveal that there are certain hybridizations between the electron orbitals of the involved oxygen and hydrogen atoms in the C=O:HO hydrogen bond.

  14. An ab initio study of the C2H2-HF, C2H(CH3)-HF and C2(CH3)2-HF hydrogen-bonded complexes.

    Science.gov (United States)

    Ramos, Mozart N; Lopes, Kelson C; Silva, Washington L V; Tavares, Alessandra M; Castriani, Fátima A; do Monte, Silmar A; Ventura, Elizete; Araújo, Regiane C M U

    2006-02-01

    MP2/6-31++G** and B3LYP/6-31++G** ab initio molecular orbital calculations have been performed in order to obtain molecular geometries, binding energies and vibrational properties of the C2H2-HF, C2H(CH3)-HF and C2(CH3)2-HF H-bonded complexes. As expected, the more pronounced effects on the structural properties of the isolated molecules due to complexation was verified for the C[triple bond]C and H-F bond lengths, which are directly involved in the H-bond formation. These bond distances increased after complexation. BSSE uncorrected B3LYP binding energies are always lower than the corresponding MP2 values. However, the opposite trend has been verified after BSSE correction by the counterpoise method since it is much lower at B3LYP than at MP2 level. The binding energies for these complexes as well as for the HF acid submolecule modes (the HF stretching and vibrational frequency modes) showed an increasing hydrogen-bonding strength with increasing methyl substitution. The splitting in the HF in-plane and out-of-plane bending modes reflects the anisotropy in the hydrogen-bonding interaction with the pi system of the C[triple bond]C bond. The H-F stretching frequency is shifted downward after complexation and it increases with the methyl substitution. The IR intensities of the HF acid submolecule fundamentals are adequately interpreted through the atomic polar tensor of the hydrogen atom using the charge-charge flux-overlap model. The skeletal stretching modes of the Alkyne submolecule are decreased in the complex. The new vibrational modes arising from complexation show several interesting features.

  15. Explosively Bonded Gun Tube Liner Development

    Science.gov (United States)

    2015-04-01

    FOR OFFICIAL USE ONYLFGFF ARL-CR-0771 ● APR 2015 US Army Research Laboratory Explosively Bonded Gun Tube Liner Development...return it to the originator. ARL-CR-0771 ● APR 2015 US Army Research Laboratory Explosively Bonded Gun Tube Liner Development...COVERED (From - To) 12 January 2014–1 January 2015 4. TITLE AND SUBTITLE Explosively Bonded Gun Tube Liner Development 5a. CONTRACT NUMBER ORISE 1120

  16. Unraveling the molecular structure of the catalytic domain of matrix metalloproteinase-2 in complex with a triple-helical peptide by means of molecular dynamics simulations.

    Science.gov (United States)

    Díaz, Natalia; Suárez, Dimas; Valdés, Haydeé

    2013-11-26

    Herein, we present the results of a computational study that employed various simulation methodologies to build and validate a series of molecular models of a synthetic triple-helical peptide (fTHP-5) both in its native state and in a prereactive complex with the catalytic domain of the MMP-2 enzyme. First, the structure and dynamical properties of the fTHP-5 substrate are investigated by means of molecular dynamics (MD) simulations. Then, the propensity of each of the three peptide chains in fTHP-5 to be distorted around the scissile peptide bond is assessed by carrying out potential of mean force calculations. Subsequently, the distorted geometries of fTHP-5 are docked within the MMP-2 active site following a semirigid protocol, and the most stable docked structures are fully relaxed and characterized by extensive MD simulations in explicit solvent. Following a similar approach, we also investigate a hypothetical ternary complex formed between two MMP-2 catalytic units and a single fTHP-5 molecule. Overall, our models for the MMP-2/fTHP-5 complexes unveil the extent to which the triple helix is distorted to allow the accommodation of an individual peptide chain within the MMP active site.

  17. Highly improved photo-induced bias stability of sandwiched triple layer structure in sol-gel processed fluorine-doped indium zinc oxide thin film transistor

    Directory of Open Access Journals (Sweden)

    Dongha Kim

    2016-03-01

    Full Text Available In order to improve the reliability of TFT, an Al2O3 insulating layer is inserted between active fluorine doped indium zinc oxide (IZO:F thin films to form a sandwiched triple layer. All the thin films were fabricated via low-cost sol-gel process. Due to its large energy bandgap and high bonding energy with oxygen atoms, the Al2O3 layer acts as a photo-induced positive charge blocking layer that effectively blocks the migration of both holes and V o2+ toward the interface between the gate insulator and the semiconductor. The inserted Al2O3 triple layer exhibits a noticeably low turn on voltage shift of −0.7 V under NBIS as well as the good TFT performance with a mobility of 10.9 cm2/V ⋅ s. We anticipate that this approach can be used to solve the stability issues such as NBIS, which is caused by inescapable oxygen vacancies.

  18. Fourier-Mukai and Nahm transforms for holomorphic triples on elliptic curves

    Science.gov (United States)

    García-Prada, Oscar; Hernández Ruipérez, Daniel; Pioli, Fabio; Tejero Prieto, Carlos

    2005-12-01

    We define a Fourier-Mukai transform for a triple consisting of two holomorphic vector bundles over an elliptic curve and a homomorphism between them. We prove that in some cases, the transform preserves the natural stability condition for a triple. We also define a Nahm transform for solutions to natural gauge-theoretic equations on a triple—vortices—and explore some of its basic properties. Our approach combines direct methods with dimensional reduction techniques, relating triples over a curve with vector bundles over the product of the curve with the complex projective line.

  19. ACA and the Triple Aim: Musings of a Health Care Actuary.

    Science.gov (United States)

    McCarthy, Mac

    2015-01-01

    In 2008, the Institute for Healthcare Improvement (IHI) promulgated the Triple Aim, which advocates simultaneous improvements in patient experiences, improved population health and lower cost per capita. In 2010, the Patient Protection and Affordable Care Act (ACA) promised quality, affordable health care for all Americans. It's fair to assume that the framers of ACA were aware of the Triple Aim, and it is likely that much of ACA was heavily influenced by IHI's positions. So it is reasonable, from time to time, to assess ACA's impact on health care against the Triple Aim principles.

  20. Dirac operators and spectral triples for some fractal sets built on curves

    DEFF Research Database (Denmark)

    Christensen, Erik; Ivan, Cristina; Lapidus, Michel L.

    2008-01-01

    A spectral triple is an object which is described using an algebra of operators on a Hilbert space and an unbounded self-adjoint operator, called a Dirac operator. This model may be applied to the study of classical geometrical objects .The article contains a construction of a spectral triple ass...... associated to some classical fractal subsets of the plane, and it is demonstrated that you can read of many classical geometrical structures, such as distance, measure and Hausdorff dimension from the spectral triple....