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Sample records for 1d magnetophotonic crystals

  1. Intra-Brillouin-zone bandgaps due to periodic misalignment in one-dimensional magnetophotonic crystals

    NASA Astrophysics Data System (ADS)

    Wang, Fei; Lakhtakia, Akhlesh

    2008-01-01

    One-dimensional (1D) magnetophotonic crystals (MPCs) can incorporate optical gyrotropy induced by a bias magnetic field, crystalline misalignment, and differential linear birefringence in a single photonic-crystal structure. A 1D MPC whose unit cell contains two layers—one magnetophotonic, the other not—displays intra-Brillouin-zone photonic bandgaps (PBGs) in the Brillouin diagram. While the optical gyrotropy makes the PBG bandwidths tunable by a bias magnetic field, the bicrystalline misalignment modifies and can even trump this magnetic tunability. Magnetic tunability is greatly affected by a proper selection of the two materials; e.g., a large birefringence ratio between the two layers can dramatically enhance the magnetic tunability of the MPC. We also expect our 1D MPCs to be useful for detecting magnetic fields.

  2. Permittivity disorder induced Anderson localization in magnetophotonic crystals

    NASA Astrophysics Data System (ADS)

    Abdi-Ghaleh, R.; Namdar, A.

    2016-11-01

    This theoretical study was carried out to investigate the permittivity disorder induced Anderson localization of light in one-dimensional magnetophotonic crystals. It was shown that the disorder create the resonant transmittance modes associated with enhanced Faraday rotations inside the photonic band gap. The average localization length of the right- and left-handed circular polarizations (RCP and LCP), the total transmittance together with the ensemble average of the RCP and LCP phases, and the Faraday rotation of the structure were also investigated. For this purpose, the off-diagonal elements of the permittivity tensor were varied for various wavelengths of incident light. The obtained results revealed the nonreciprocal property of circular eigen modes. This study can potentially open up a new aspect for utilizing the disorder magnetophotonic structures in nonreciprocal systems such as isolators and circulators.

  3. Magneto-optical switching of Bloch surface waves in magnetophotonic crystals

    NASA Astrophysics Data System (ADS)

    Romodina, M. N.; Soboleva, I. V.; Fedyanin, A. A.

    2016-10-01

    Bloch-surface-wave (BSW) excitation controlled by Faraday rotation in one-dimensional magnetophotonic crystals is presented. Dispersion curves of the Bloch surface wave and waveguide modes of magnetophotonic crystals consisting of silicon dioxide and bismuth-substituted yttrium-iron-garnet (Bi:YIG) quarter-wavelength-thick layers are calculated using Berreman's 4×4 transfer matrix method. Enhanced Faraday rotation observed in the magnetophotonic crystals in the spectral vicinity of the BSW resonance enables the magneto-optical switching of BSWs. The excitation of the BSWs at the magnetophotonic crystal surface for p-polarized incident light is induced by magneto-optical activity in the Bi:YIG layers.

  4. Magneto-photonic crystals for optical sensing applications

    NASA Astrophysics Data System (ADS)

    Dissanayake, Neluka

    Among the optical structures investigated for optical sensing purpose, a significant amount of research has been conducted on photonic crystal based sensors. A particular advantage of photonic crystal based sensors is that they show superior sensitivity for ultra-small volume sensing. In this study we investigate polarization changes in response to the changes in the cover index of magneto-optic active photonic band gap structures. One-dimensional photonic-band gap structures fabricated on iron garnet materials yield large polarization rotations at the band gap edges. The enhanced polarization effects serve as an excellent tool for chemical sensing showing high degree of sensitivity for photonic crystal cover refractive index changes. The one dimensional waveguide photonic crystals are fabricated on single-layer bismuth-substituted rare earth iron garnet films ((Bi, Y, Lu)3(Fe, Ga)5O12 ) grown by liquid phase epitaxy on gadolinium gallium garnet substrates. Band gaps have been observed where Bragg scattering conditions links forward-going fundamental waveguide modes to backscattered high-order waveguide modes. Large near-band-edge polarization rotations which increase progressively with backscattered-mode order have been experimentally demonstrated for multiple samples with different composition, film thickness and fabrication parameters. Experimental findings are supported by theoretical analysis of Bloch modes polarization states showing that large near stop-band edge rotations are induced by the magneto-photonic crystal. Theoretical and experimental analysis conducted on polarization rotation sensitivity to waveguide photonic crystal cover refractive index changes shows a monotonic enhancement of the rotation with cover index. The sensor is further developed for selective chemical sensing by employing Polypyrrole as the photonic crystal cover layer. Polypyrrole is one of the extensively studied conducting polymers for selective analyte detection. Successful

  5. Design of one-dimensional magnetophotonic crystals operating at visible wavelengths

    NASA Astrophysics Data System (ADS)

    Abdi-Ghaleh, Reza; Asad, Mohsen

    2015-01-01

    In this paper, a proposal for designing the one-dimensional magnetophotonic crystals operating at visible wavelengths is presented. To this aim, a binary all-dielectric periodic structure is considered with quarter wavelength optical thicknesses condition. However, the Bi:YIG as a magneto-optical defect layer with two different optical thicknesses of λ 0/2 and 4 λ 0 is utilized. Using the 4 × 4 transfer matrix method the defect mode properties of the considered structures are investigated regarding the different period numbers and various magneto-optical defect layer positions. Analyzing the transmittance, Faraday rotation and absorption coefficient of these structures for the 720 nm visible light, the optimum structures are proposed for both cases of magneto-optical defect layer thicknesses. These structures may have potential applications in designing the miniaturized magneto-optical devices such as magneto-optical sensors and isolators and integrated photonic elements.

  6. Nonlinear magneto-optical effects in all-garnet magnetophotonic crystals

    NASA Astrophysics Data System (ADS)

    Murzina, T. V.; Razdolski, I. E.; Aktsipetrov, O. A.; Grishin, A. M.; Khartsev, S. I.

    2009-04-01

    Nonlinear magneto-optical properties of all-garnet magnetophotonic crystals composed of alternating layers of ferromagnetic Bi 3Fe 5O 12 (BIG) and Sm 3Ga 5O 12 quarter-wavelength layers with a half-wavelength BIG microcavity mode are presented. The samples are grown by rf-magnetron sputtering on non-magnetic GGG substrate. Many-fold enhancement of the magnetization-induced effects in second-harmonic generation (SHG) as compared with linear magneto-optical effects are observed: the SHG magnetic contrast up to 50% and magnetization-induced rotation of the polarization plane of about 90° are measured at the resonance microcavity wavelengh of λ=779 nm.

  7. Preliminary studies of 3D magnetophotonic crystals designed from a template stuffed by sol-gel process

    NASA Astrophysics Data System (ADS)

    Kekesi, R.; Royer, F.; Blanc Mignon, M. F.; Goutaland, F.; Chatelon, J. P.; Tombacz, E.; Jamon, D.

    2010-05-01

    Based on the previous work of Nishijima [1], the aim of this work is to realize 3D magnetophotonic crystals (MPC) by a sol-gel approach, in order to obtain a magneto-optical material with a large merit factor. These MPC are made by immersion of an opal template of polystyrene spheres in a sol-gel TEOS preparation doped by magnetic nanoparticles. The template can be realized using centrifugation or sedimentation, and it is removed after the solidification of the doped matrix by an immersion in ethyl acetate. Calculations made on 1D structures confirm that a periodic arrangement of a magneto-optical material is a way to increase the Faraday Rotation and the merite factor. The characterization of the samples is made by SEM and UV-VIS spectrophotometry. In virtue of the SEM pictures we can establish that the template is well-structured, what is confirmed by a Photonic Band Gap (PBG) in the spectrophotometry spectral. The central wavelength of the PBG depends on the size of the polystyrene spheres. The final MPC obtained with a silica matrix doped by maghemite nanoparticles has also well-structured areas. Ongoing works concern the study of the Farady rotation as a function of the wavelength.

  8. Magnetic properties of the magnetophotonic crystal based on bismuth iron garnet

    NASA Astrophysics Data System (ADS)

    Popova, Elena; Magdenko, Liubov; Niedoba, Halina; Deb, Marwan; Dagens, Béatrice; Berini, Bruno; Vanwolleghem, Mathias; Vilar, Christèle; Gendron, François; Fouchet, Arnaud; Scola, Joseph; Dumont, Yves; Guyot, Marcel; Keller, Niels

    2012-11-01

    This article reports on the magnetism of continuous and patterned bismuth iron garnet (Bi3Fe5O12 or BIG) thin films for magnetophotonic crystal (MPC) applications. The exact knowledge of the magnetic properties is crucial for the design of fully functional MPC. BIG thin films were grown on several types of isostructural substrates by pulsed laser deposition. The growth conditions and bismuth transfer were optimized to obtain good quality magneto-optically active films compatible with nanostructuring process. MPC were successfully fabricated from BIG/GGG(001) films with low roughness and high Faraday rotation. Magnetic characteristics (magnetization, anisotropy, magnetic domains, magnetization reversal) of the continuous BIG films and MPC were extensively studied and compared to the results of the micromagnetic simulations performed for MPC with different anisotropy. The present study shows that the fabrication of the MPC structure lowers the magnetocrystalline and uniaxial in-plane anisotropies and induces a partial out-of-plane magnetization. External field smaller than 2000 G is sufficient to ensure the out-of-plane saturation of magnetization for optimum device operation, in agreement with micromagnetic calculations. The experimentally determined magnetic properties of MPC are fully compatible with the device operation.

  9. Propagation of Electromagnetic Waves in 3D Opal-based Magnetophotonic Crystals

    NASA Astrophysics Data System (ADS)

    Pardavi-Horvath, Martha; Makeeva, Galina S.; Golovanov, Oleg A.; Rinkevich, Anatolii B.

    2013-03-01

    Opals, a class of self-organized 3D nanostructures, are typical representatives of photonic bandgap structures. The voids inside of the opal structure of close packed SiO2 spheres can be infiltrated by a magnetic material, creating magnetically tunable magnetophotonic crystals with interesting and potentially useful properties at GHz and THz frequencies. The propagation of electromagnetic waves at microwave frequencies was investigated numerically in SiO2 opal based magnetic nanostructures, using rigorous mathematical models to solve Maxwell's equations complemented by the Landau-Lifshitz equation with electrodynamic boundary conditions. The numerical approach is based on Galerkin's projection method using the decomposition algorithm on autonomous blocks with Floquet channels. The opal structure consists of SiO2 nanospheres, with inter-sphere voids infiltrated with nanoparticles of Ni-Zn ferrites. Both the opal matrix and the ferrite are assumed to be lossy. A model, taking into account the real structure of the ferrite particles in the opal's voids was developed to simulate the measured FMR lineshape of the ferrite infiltrated opal. The numerical technique shows an excellent agreement when applied to model recent experimental data on similar ferrite opals.

  10. Experimental studies of cobalt ferrite nanoparticles doped silica matrix 3D magneto-photonic crystals

    NASA Astrophysics Data System (ADS)

    Abou Diwan, E.; Royer, F.; Kekesi, R.; Jamon, D.; Blanc-Mignon, M. F.; Neveu, S.; Rousseau, J. J.

    2013-05-01

    In this paper, we present the synthesis and the optical properties of 3D magneto-photonic structures. The elaboration process consists in firstly preparing then infiltrating polystyrene direct opals with a homogeneous solution of sol-gel silica precursors doped by cobalt ferrite nanoparticles, and finally dissolving the polystyrene spheres. Scanning Electron Microscopy (SEM) images of the prepared samples clearly evidence a periodic arrangement. Using a home-made polarimetric optical bench, the transmittance as a function of the wavelength, the Faraday rotation as a function of the applied magnetic field, and the Faraday ellipticity as a function of the wavelength and as a function of the applied magnetic field were measured. The existence of deep photonic band gaps (PBG), the unambiguous magnetic character of the samples and the qualitative modification of the Faraday ellipticity in the area of the PBG are evidenced.

  11. A 1-D dusty plasma photonic crystal

    SciTech Connect

    Mitu, M. L.; Ticoş, C. M.; Toader, D.; Banu, N.; Scurtu, A.

    2013-09-21

    It is demonstrated numerically that a 1-D plasma crystal made of micron size cylindrical dust particles can, in principle, work as a photonic crystal for terahertz waves. The dust rods are parallel to each other and arranged in a linear string forming a periodic structure of dielectric-plasma regions. The dispersion equation is found by solving the waves equation with the boundary conditions at the dust-plasma interface and taking into account the dielectric permittivity of the dust material and plasma. The wavelength of the electromagnetic waves is in the range of a few hundred microns, close to the interparticle separation distance. The band gaps of the 1-D plasma crystal are numerically found for different types of dust materials, separation distances between the dust rods and rod diameters. The distance between levitated dust rods forming a string in rf plasma is shown experimentally to vary over a relatively wide range, from 650 μm to about 1350 μm, depending on the rf power fed into the discharge.

  12. Low-loss Y-junction two-dimensional magneto-photonic crystals circulator using a ferrite cylinder

    NASA Astrophysics Data System (ADS)

    Wang, Yong; Zhang, Dengguo; Xu, Shixiang; Ouyang, Zhengbiao; Li, Jingzhen

    2016-06-01

    A new defect structure of two-dimensional magnetic-photonic crystal is given and a new three-port Y-junction circulator using a ferrite cylinder is proposed in this short paper. Based on the agreements between the resonance frequency of micro-cavity constructed by a point defect in the 2D triangular lattice photonic crystal with those numerical results of corresponding literatures, external characteristics of the circulator were calculated by the plane wave expansion method and finite element method. According to the scaling theory of Maxwell's equations, a 3 cm Y-junction 2D MPCs circulator is developed by scaling the radius of the center ferrite cylinder. The results show that there is a significant improvement for insertion loss 0.062 dB and isolation 26.2 dB compared with those in literatures.

  13. Extended-Range Ultrarefractive 1D Photonic Crystal Prisms

    NASA Technical Reports Server (NTRS)

    Ting, David Z.

    2007-01-01

    A proposal has been made to exploit the special wavelength-dispersive characteristics of devices of the type described in One-Dimensional Photonic Crystal Superprisms (NPO-30232) NASA Tech Briefs, Vol. 29, No. 4 (April 2005), page 10a. A photonic crystal is an optical component that has a periodic structure comprising two dielectric materials with high dielectric contrast (e.g., a semiconductor and air), with geometrical feature sizes comparable to or smaller than light wavelengths of interest. Experimental superprisms have been realized as photonic crystals having three-dimensional (3D) structures comprising regions of amorphous Si alternating with regions of SiO2, fabricated in a complex process that included sputtering. A photonic crystal of the type to be exploited according to the present proposal is said to be one-dimensional (1D) because its contrasting dielectric materials would be stacked in parallel planar layers; in other words, there would be spatial periodicity in one dimension only. The processes of designing and fabricating 1D photonic crystal superprisms would be simpler and, hence, would cost less than do those for 3D photonic crystal superprisms. As in 3D structures, 1D photonic crystals may be used in applications such as wavelength-division multiplexing. In the extended-range configuration, it is also suitable for spectrometry applications. As an engineered structure or artificially engineered material, a photonic crystal can exhibit optical properties not commonly found in natural substances. Prior research had revealed several classes of photonic crystal structures for which the propagation of electromagnetic radiation is forbidden in certain frequency ranges, denoted photonic bandgaps. It had also been found that in narrow frequency bands just outside the photonic bandgaps, the angular wavelength dispersion of electromagnetic waves propagating in photonic crystal superprisms is much stronger than is the angular wavelength dispersion obtained

  14. Ultrathin conformal coating for complex magneto-photonic structures.

    PubMed

    Pascu, Oana; Caicedo, José Manuel; López-García, Martín; Canalejas, Víctor; Blanco, Álvaro; López, Cefe; Arbiol, Jordi; Fontcuberta, Josep; Roig, Anna; Herranz, Gervasi

    2011-11-01

    We report on an extremely fast and versatile synthetic approach, based on microwave assisted sol-gel chemistry, that allows a conformal nanometric coating of intricate three-dimensional structures. Using this methodology, we have achieved a conformal coverage of large areas of three-dimensional opals with a superparamagnetic manganese ferrite layer, yielding magneto-photonic crystals with excellent quality. The use of a ternary oxide for the ultrathin coating demonstrates the potential of this methodology to realize three-dimensional structures with complex materials that may find applications beyond photonics, such as energy, sensing or catalysis. PMID:21987109

  15. Magnetophotonic response of three-dimensional opals.

    PubMed

    Caicedo, José Manuel; Pascu, Oana; López-García, Martín; Canalejas, Víctor; Blanco, Alvaro; López, Cefe; Fontcuberta, Josep; Roig, Anna; Herranz, Gervasi

    2011-04-26

    Three-dimensional magnetophotonic crystals (3D-MPCs) are being postulated as appropriate platforms to tailor the magneto-optical spectral response of magnetic materials and to incorporate this functionality in a new generation of optical devices. By infiltrating self-assembled inverse opal structures with monodisperse nickel nanoparticles we have fabricated 3D-MPCs that show a sizable enhancement of the magneto-optical signal at frequencies around the stop-band edges of the photonic crystals. We have established a proper methodology to disentangle the intrinsic magneto-optical spectra from the nonmagnetic optical activity of the 3D-MPCs. The results of the optical and magneto-optical characterization are consistent with a homogeneous magnetic infiltration of the opal structure that gives rise to both a red-shift of the optical bandgap and a modification of the magneto-optical spectral response due to photonic bandgap effects. The results of our investigation demonstrate the potential of 3D-MPCs fabricated following the approach outlined here and offer opportunities to adapt the magneto-optical spectral response at optical frequencies by appropriate design of the opal structure or magnetic field strength.

  16. Engineered atom-light interactions in 1D photonic crystals

    NASA Astrophysics Data System (ADS)

    Martin, Michael J.; Hung, Chen-Lung; Yu, Su-Peng; Goban, Akihisa; Muniz, Juan A.; Hood, Jonathan D.; Norte, Richard; McClung, Andrew C.; Meenehan, Sean M.; Cohen, Justin D.; Lee, Jae Hoon; Peng, Lucas; Painter, Oskar; Kimble, H. Jeff

    2014-05-01

    Nano- and microscale optical systems offer efficient and scalable quantum interfaces through enhanced atom-field coupling in both resonators and continuous waveguides. Beyond these conventional topologies, new opportunities emerge from the integration of ultracold atomic systems with nanoscale photonic crystals. One-dimensional photonic crystal waveguides can be engineered for both stable trapping configurations and strong atom-photon interactions, enabling novel cavity QED and quantum many-body systems, as well as distributed quantum networks. We present the experimental realization of such a nanophotonic quantum interface based on a nanoscale photonic crystal waveguide, demonstrating a fractional waveguide coupling of Γ1 D /Γ' of 0 . 32 +/- 0 . 08 , where Γ1 D (Γ') is the atomic emission rate into the guided (all other) mode(s). We also discuss progress towards intra-waveguide trapping of ultracold Cs. This work was supported by the IQIM, an NSF Physics Frontiers Center with support from the Moore Foundation, the DARPA ORCHID program, the AFOSR QuMPASS MURI, the DoD NSSEFF program, NSF, and the Kavli Nanoscience Institute (KNI) at Caltech.

  17. Coherent thermal conductance of 1-D photonic crystals

    NASA Astrophysics Data System (ADS)

    Tschikin, Maria; Ben-Abdallah, Philippe; Biehs, Svend-Age

    2012-10-01

    We present an exact calculation of coherent thermal conductance in 1-D multilayer photonic crystals using the S-matrix method. In particular, we study the thermal conductance in a bilayer structure of Si/vacuum or Al2O3/vacuum slabs by means of the exact radiative heat flux expression. Based on the results obtained for the Al2O3/vacuum structure we show by comparison with previous works that the material losses and (localized) surface modes supported by the inner layers play a fundamental role and cannot be omitted in the definition of thermal conductance. Our results could have significant implications in the conception of efficient thermal barriers.

  18. Parametric Simulations of Slanted 1D Photonic Crystal Sensors.

    PubMed

    Breuer-Weil, Aaron; Almasoud, Naif Nasser; Abbasi, Badaruddin; Yetisen, Ali K; Yun, Seok-Hyun; Butt, Haider

    2016-12-01

    Photonic crystals and band gap materials act as manipulators of light and have a plethora of applications. They are made up of stacks of alternating dielectric constants. This article shows the simulations of an inclined, one dimensional and tuneble photonic crystal, using numerical finite element methods. The photonic crystal was made up of silver nanoparticles embedded in a hydrogel matrix and it has the ability to change and recover its periodicity. A series of factors concerning the geometry of the lattice were tested in order to analyze the efficiency, performance and optimize the properties of the optical sensor. These factors range from the size of the nanoparticles and their density within the stacks, to observing the effect of diffraction angle in readouts. PMID:27000025

  19. Tunable Design of Structural Colors Produced by Pseudo-1D Photonic Crystals of Graphene Oxide.

    PubMed

    Tong, Liping; Qi, Wei; Wang, Mengfan; Huang, Renliang; Su, Rongxin; He, Zhimin

    2016-07-01

    It is broadly observed that graphene oxide (GO) films appear transparent with a thickness of about several nanometers, whereas they appear dark brown or almost black with thickness of more than 1 μm. The basic color mechanism of GO film on a sub-micrometer scale, however, is not well understood. This study reports on GO pseudo-1D photonic crystals (p1D-PhCs) exhibiting tunable structural colors in the visible wavelength range owing to its 1D Bragg nanostructures. Striking structural colors of GO p1D-PhCs could be tuned by simply changing either the volume or concentration of the aqueous GO dispersion during vacuum filtration. Moreover, the quantitative relationship between thickness and reflection wavelength of GO p1D-PhCs has been revealed, thereby providing a theoretical basis to rationally design structural colors of GO p1D-PhCs. The spectral response of GO p1D-PhCs to humidity is also obtained clearly showing the wavelength shift of GO p1D-PhCs at differently relative humidity values and thus encouraging the integration of structural color printing and the humidity-responsive property of GO p1D-PhCs to develop a visible and fast-responsive anti-counterfeiting label. The results pave the way for a variety of potential applications of GO in optics, structural color printing, sensing, and anti-counterfeiting.

  20. Computational Study and Analysis of Structural Imperfections in 1D and 2D Photonic Crystals

    SciTech Connect

    Maskaly, Karlene Rosera

    2005-06-01

    Dielectric reflectors that are periodic in one or two dimensions, also known as 1D and 2D photonic crystals, have been widely studied for many potential applications due to the presence of wavelength-tunable photonic bandgaps. However, the unique optical behavior of photonic crystals is based on theoretical models of perfect analogues. Little is known about the practical effects of dielectric imperfections on their technologically useful optical properties. In order to address this issue, a finite-difference time-domain (FDTD) code is employed to study the effect of three specific dielectric imperfections in 1D and 2D photonic crystals. The first imperfection investigated is dielectric interfacial roughness in quarter-wave tuned 1D photonic crystals at normal incidence. This study reveals that the reflectivity of some roughened photonic crystal configurations can change up to 50% at the center of the bandgap for RMS roughness values around 20% of the characteristic periodicity of the crystal. However, this reflectivity change can be mitigated by increasing the index contrast and/or the number of bilayers in the crystal. In order to explain these results, the homogenization approximation, which is usually applied to single rough surfaces, is applied to the quarter-wave stacks. The results of the homogenization approximation match the FDTD results extremely well, suggesting that the main role of the roughness features is to grade the refractive index profile of the interfaces in the photonic crystal rather than diffusely scatter the incoming light. This result also implies that the amount of incoherent reflection from the roughened quarterwave stacks is extremely small. This is confirmed through direct extraction of the amount of incoherent power from the FDTD calculations. Further FDTD studies are done on the entire normal incidence bandgap of roughened 1D photonic crystals. These results reveal a narrowing and red-shifting of the normal incidence bandgap with

  1. Structure, electrochemical properties and capacitance performance of polypyrrole electrodeposited onto 1-D crystals of iridium complex

    NASA Astrophysics Data System (ADS)

    Wysocka-Żołopa, Monika; Winkler, Krzysztof

    2015-12-01

    Composites of polypyrrole and one-dimensional iridium complex crystals [(C2H5)4N]0.55[IrCl2(CO)2] were prepared by in situ two-step electrodeposition. Initially, iridium complex crystals were formed during [IrCl2(CO)2]- complex oxidation. Next, pyrrole was electropolymerized on the surface of the iridium needles. The morphology of the composite was investigated by scanning and transmission electron microscopy. At positive potentials, the iridium complex crystals and the polypyrrole were oxidized. In aprotic solvents, oxidation of the iridium complex crystals resulted in their dissolution. In water containing tetra(n-butyl)ammonium chlorides, the 1-D iridium complex crystals were reversibly oxidized. The product of the iridium complex oxidation remained on the electrode surface in crystalline form. The iridium complex needles significantly influenced the redox properties of the polymer. The polypyrrole involved electrode processes become more reversible in presence of crystals of iridium complex. The current of polypyrrole oxidation was higher compared to that of pure polypyrrole and the capacitance properties of the polymer were significantly enhanced. A specific capacitance as high as 590 F g-1 was obtained for a composite of polypyrrole and 1-D crystals of the iridium complex in water containing tetra(n-butyl)ammonium chloride. This value is approximately twice as high as the capacitance of the pure polymer deposited onto the electrode surface.

  2. Crystallization, Crystal Orientation and Morphology of Poly(ethylene oxide) under 1D Defect-Free Nanoscale Confinement

    NASA Astrophysics Data System (ADS)

    Hsiao, Ming-Siao; Zheng, Joseph X.; van Horn, Ryan M.; Quirk, Roderic P.; Thomas, Edwin L.; Lotz, Bernard; Cheng, Stephen Z. D.

    2009-03-01

    One-dimensional (1-D) defect-free nanoscale confinement is created by growing single crystals of PS-b-PEO block copolymers in dilute solution. Those defect-free, 1-D confined lamellae having different PEO layer thicknesses in PS-b-PEO lamellar single crystals (or crystal mats) were used to study the polymer recrystallization and crystal orientation evolution as a function of recrystallization temperature (Trx) because the Tg^PS is larger than Tm^PEO in the PS-b-PEO single crystal. The results are summarized as follows. First, by the combination of electron diffraction and known PEO crystallography, the crystallization of PEO only takes place at Trx<-5^oC. Meanwhile a unique tilted PEO orientation is formed at Trx >-5^oC after self-seeding. The origin of the formation of tilted chains in the PEO crystal will be addressed. Second, from the analysis of 2D WAXD patterns of crystal mats, it is shown that the change in PEO c-axis orientation from homogeneous at low Trx to homeotropic at higher Trx transitions sharply, within 1^oC. The mechanism inducing this dramatic change in crystal orientation will be investigated in detail.

  3. Structural and magnetic properties of Fe1+dTe single crystals

    NASA Astrophysics Data System (ADS)

    Mizuguchi, Yoshikazu; Hamada, Kentaro; Miura, Osuke

    We have grown single crystals of Fe1+dTe by a conventional self-flux method. We obtained plate-like single crystals with dnom ≥ 0.1. The value of the magnetization increased with increasing excess Fe concentration, and a broadening of the antiferromagnetic transition was observed for dnom >1.15. Further, we noted that the antiferromagnetic transition of Fe1.134Te (dnom = 0.15) was clearly suppressed to a lower temperature, which would indicate a possibility of controllability of magnetism by excess Fe concentration.

  4. Crystal orbital studies on the 1D silic-diyne nanoribbons and nanotubes.

    PubMed

    Zhu, Ying; Bai, Hongcun; Huang, Yuanhe

    2016-02-01

    This work presents crystal orbital studies on novel one-dimensional (1D) nanoscale materials derived from a Si-diyne sheet, based on the density functional theory. The two-dimensional (2D) Si-diyne layer is observed to be carbo-merized silicene, with a similar structure to graphdiyne. The 2D Si-diyne and its 1D ribbons and tubes, of different size and chirality, have been addressed systematically. The low dimensional Si-diyne materials studied exhibit relatively high stability, according to phonon-frequency calculations and molecular dynamics simulations. With comparable diameters, the Si-diyne tubes have lower strain energies than silicene and silicon carbide nanotubes. The Si-diyne layer and its 1D derivatives are all semiconductors, regardless of the size and chirality of the strips and tubes. In addition, the band gaps of the 1D Si-diyne nanoribbons and nanotubes with different chirality, always monotonically decrease as their sizes increases. A quantitative relationship between the band gap and the size of the ribbons and tubes was obtained. The mobility of charge carriers for the 1D Si-diyne structures was also investigated. It was found that both hole and electron mobility of the ribbons and tubes exhibit linear increase with increasing size. The electrons have greater mobility than the holes for each strip and tube. In addition, the mechanical properties of the Si-diyne nanostructures were also investigated by calculation of the Young's modulus and the Poisson's ratio. PMID:26744378

  5. Study of phase transformation and crystal structure for 1D carbon-modified titania ribbons

    SciTech Connect

    Zhou, Lihui Zhang, Fang; Li, Jinxia

    2014-02-15

    One-dimensional hydrogen titanate ribbons were successfully prepared with hydrothermal reaction in a highly basic solution. A series of one-dimensional carbon-modified TiO{sub 2} ribbons were prepared via calcination of the mixture of hydrogen titanate ribbons and sucrose solution under N{sub 2} flow at different temperatures. The phase transformation process of hydrogen titanate ribbons was investigated by in-situ X-ray diffraction at various temperatures. Besides, one-dimensional carbon-modified TiO{sub 2} ribbons calcined at different temperatures were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, nitrogen adsorption isotherms, diffuse reflectance ultraviolet–visible spectroscopy, and so on. Carbon-modified TiO{sub 2} ribbons showed one-dimensional ribbon crystal structure and various crystal phases of TiO{sub 2}. After being modified with carbon, a layer of uniform carbon film was coated on the surface of TiO{sub 2} ribbons, which improved their adsorption capacity for methyl orange as a model organic pollutant. One-dimensional carbon-modified TiO{sub 2} ribbons also exhibited enhanced visible-light absorbance with the increase of calcination temperatures. - Highlights: • The synthesis of 1D carbon-modified TiO{sub 2} ribbons. • The phase transformation of 1D carbon-modified TiO{sub 2} ribbons. • 1D carbon-modified TiO{sub 2} exhibites enhanced visible-light absorbance.

  6. Metal-dielectric photonic crystal superlattice: 1D and 2D models and empty lattice approximation

    NASA Astrophysics Data System (ADS)

    Kichin, G.; Weiss, T.; Gao, H.; Henzie, J.; Odom, T. W.; Tikhodeev, S. G.; Giessen, H.

    2012-10-01

    Periodic nanostructures are one of the main building blocks in modern nanooptics. They are used for constructing photonic crystals and metamaterials and provide optical properties that can be changed by adjusting the geometrical parameters of the structures. In this paper the optical properties of a photonic crystal slab with a 2D superlattice are discussed. The structure consists of a gold layer with a finite periodic pattern of air holes that is itself repeated periodically with a larger superperiod. We propose simplified 1D and 2D models to understand the physical nature of Wood's anomalies in the optical spectra of the investigated structure. The latter are attributed to the Rayleigh anomalies, surface plasmon Bragg resonances and the hole-localized plasmons.

  7. Mechanisms of 1D crystal growth in reactive vapor transport: indium nitride nanowires.

    PubMed

    Vaddiraju, Sreeram; Mohite, Aditya; Chin, Alan; Meyyappan, M; Sumanasekera, Gamini; Alphenaar, Bruce W; Sunkara, Mahendra K

    2005-08-01

    Indium nitride (InN) nanowire synthesis using indium (In) vapor transport in a dissociated ammonia environment (reactive vapor transport) is studied in detail to understand the nucleation and growth mechanisms involved with the so-called "self-catalysis" schemes. The results show that the nucleation of InN crystal occurs first on the substrate. Later, In droplets are formed on top of the InN crystals because of selective wetting of In onto InN crystals. Further growth via liquid-phase epitaxy through In droplets leads the growth in one dimension (1D), resulting in the formation of InN nanowires. The details about the nucleation and growth aspects within these self-catalysis schemes are rationalized further by demonstrating the growth of heteroepitaxially oriented nanowire arrays on single-crystal substrates and "tree-like" morphologies on a variety of substrates. However, the direct nitridation of In droplets using dissociated ammonia results in the spontaneous nucleation and basal growth of nanowires directly from the In melt surface, which is quite different from the above-mentioned nucleation mechanism with the reactive vapor transport case. The InN nanowires exhibit a band gap of 0.8 eV, whereas the mixed phase of InN and In(2)O(3) nanowires exhibit a peak at approximately 1.9 eV in addition to that at 0.8 eV.

  8. Label-free optical detection of bacteria on a 1-D photonic crystal of porous silicon

    NASA Astrophysics Data System (ADS)

    Wu, Chia-Chen; Alvarez, Sara D.; Rang, Camilla U.; Chao, Lin; Sailor, Michael J.

    2009-02-01

    The construction of a specific, label-free, bacteria biosensor using porous silicon 1-D photonic crystals will be described. Bacteria resident on the surface of porous silicon act as scattering centers for light resonant with the photonic crystal; the diffusely scattered light possesses the optical spectrum of the underlying photonic crystal. Using a spectrometer fitted to a light microscope, the bacteria are imaged without using exogenous dyes or labels and are quantified by measuring the intensity of scattered light. In order to selectively bind and identify bacteria using porous Si, we use surface modifications to reduce nonspecific binding to the surface and to engineer bacteria specificity onto the surface. Bovine serum albumin (BSA) was adsorbed to the porous Si surface to reduce nonspecific binding of bacteria. The coatings were then chemically activated to immobilize polyclonal antibodies specific to Escherichia coli. Two E. coli strains were used in our study, E. coli DH5α and non-pathogenic enterohemorrhagic Escherichia coli (EHEC) strain. The nonpathogenic Vibrio cholerae O1 strain was used to test for antibody specificity. Successful attachment of antibodies was measured using fluorescence microscopy and the scattering method was used to test for bacteria binding specificity.

  9. Photonic clays: a new family of functional 1D photonic crystals.

    PubMed

    Lotsch, Bettina V; Ozin, Geoffrey A

    2008-10-28

    Clays have shown potential as intelligent optical sensing platforms when integrated into a one-dimensional photonic crystal (PC) environment. The clay component imparts intrinsic functionality to the multilayer system by combining the signature ion exchange with the tunable structural color of photonic crystals, giving rise to environmentally sensitive photonic clay architectures. We have fabricated different Laponite-based 1D PCs and clay defect PCs by simple bottom-up self-assembly methodologies and elaborate their working principles and chemically encoded optical response. Accessibility of the multilayer system to analytes is studied on the background of the barrier properties of clays and diffusion control by the mesoporous oxide layers. The time dependence of analyte uptake and the extent and driving force for analyte release are pointed out and discussed in the context of different interactions between the clay layers and analytes. We demonstrate the possibility of optical cycling associated with repeated analyte uptake and removal processes, rendering photonic clays recyclable and low cost sensing platforms with simple optical read-out.

  10. A tiny gas-sensor system based on 1D photonic crystal

    NASA Astrophysics Data System (ADS)

    Bouzidi, A.; Bria, D.; Akjouj, A.; Pennec, Y.; Djafari-Rouhani, B.

    2015-12-01

    We present a gas monitoring system for detecting the gas concentration in ambient air. This sensor is based on a 1D photonic crystal formed by alternating layers of magnesium fluoride (MgF2) and silicon (Si) with an empty layer in the middle. The lamellar cavity (defect layer) will be filled with polluted air that has a refractive index close to that of pure air, varying between n 0  =  1.00 to n 0  =  1.01. The transmission spectrum of this sensor is calculated by the Green function approach. The numerical results show that the transmission peak, which appears in the gap, is caused by the infiltration of impure air into the empty middle layer. This transmission peak can be used for detection purposes in real-time environmental monitoring. The peak frequency is sensitive to the air-gas mixture, and a variation in the refractive index as small as Δn  =  10-5 can be detected. A sensitivity, Δλ/Δn, of 700 nm per refractive index unit (RIU) is achieved with this sensor.

  11. Effects of vanadium- and iron-doping on crystal morphology and electrochemical properties of 1D nanostructured manganese oxides

    NASA Astrophysics Data System (ADS)

    Yoo, Ha Na; Park, Dae Hoon; Hwang, Seong-Ju

    One-dimensional (1D) nanostructures of vanadium- and iron-doped manganese oxides, Mn 1- xM xO 2 (M = V and Fe), are synthesized via one-pot hydrothermal reactions. The results of X-ray diffraction studies and electron microscopic analyses demonstrate that all the present 1D nanostructured materials possess α-MnO 2-type structure. While the vanadium dopants produce 1D nanorods with a smaller aspect ratio of ∼3-5, iron dopants produce 1D nanowires with a high aspect ratio of >20. X-ray absorption spectroscopy clearly shows that the dopant vanadium ions are stabilized in tetravalent oxidation state with distorted octahedral symmetry, while the iron ions are stabilized in trivalent oxidation state with regular octahedral symmetry. Significant local structural distortion and size mismatch of dopant vanadium ions are responsible for the low aspect ratio of the vanadium-doped nanorods through the less effective growth of a 1D nanostructure. According to electrochemical measurements, doping with Fe and V can improve the electrode performance of 1D nanostructured manganate and such a positive effect is much more prominent for the iron dopant. The present study clearly indicates that doping with Fe and V provides an effective way of tailoring the crystal dimension and electrochemical properties of 1D nanostructured manganese oxides.

  12. Photonic Crystals: Tunable Design of Structural Colors Produced by Pseudo-1D Photonic Crystals of Graphene Oxide (Small 25/2016).

    PubMed

    Tong, Liping; Qi, Wei; Wang, Mengfan; Huang, Renliang; Su, Rongxin; He, Zhimin

    2016-07-01

    The production of structural colors based on graphene oxide (GO) pseudo-one-dimensional photonic crystals (p1D-PhCs) in the visible spectrum is reported on page 3433 by W. Qi and co-workers. The structural colors could be tuned by simply changing either the volume or concentration of the aqueous GO dispersion. Moreover, GO p1D-PhCs exhibit visible and rapid responsiveness to humidity.

  13. Mimicking bone nanostructure by combining block copolymer self-assembly and 1D crystal nucleation.

    PubMed

    Chen, Xi; Wang, Wenda; Cheng, Shan; Dong, Bin; Li, Christopher Y

    2013-09-24

    The orientation and spatial distribution of nanocrystals in the organic matrix are two distinctive structural characteristics associated with natural bone. Synthetic soft materials have been used to successfully control the orientation of mineral crystals. The spatial distribution of minerals in a synthetic scaffold, however, has yet to be reproduced in a biomimetic manner. Herein, we report using block copolymer-decorated polymer nanofibers to achieve biomineralized fibrils with precise control of both mineral crystal orientation and spatial distribution. Exquisite nanoscale structural control in biomimetic hybrid materials has been demonstrated.

  14. Electron-phonon interaction in quasi-1D ternary mixed crystals of polar semiconductors

    NASA Astrophysics Data System (ADS)

    Fan, Yunpeng; Hou, Junhua

    2015-07-01

    The electron-optical-phonon interaction between an electron and two branches of LO-phonon modes in a quasi-one-dimensional ternary mixed crystal (TMC) of polar semiconductors is studied. The new electron-phonon interaction Hamiltonian including the unit-cell volume variation in TMCs is obtained by using the modified random element isodisplacement model and Born-Huang method. The energies of polaron are numerically calculated for several systems of III-V compounds. A group of III-nitride mixed crystals is also taken into numerical calculation in our theory. It is verified theoretically that the obvious nonlinearity of the polaronic energy and effective mass with the composition is essential and the unit-cell volume effects cannot be neglected except the very weak e-p coupling.

  15. 1D cyanide complexes with 2-pyridinemethanol: Synthesis, crystal structures and spectroscopic properties

    NASA Astrophysics Data System (ADS)

    Sayın, Elvan; Kürkçüoğlu, Güneş Süheyla; Yeşilel, Okan Zafer; Hökelek, Tuncer

    2015-12-01

    Two new one-dimensional coordination polymers, [Cu(hmpH)2Pd(μ-CN)2(CN)2]n (1) and [Cu(hmpH)2Pt(μ-CN)2(CN)2]n (2), (hmpH = 2-pyridinemethanol), have been synthesized and characterized by vibrational (FT-IR and Raman) spectroscopy, single crystal X-ray diffraction, thermal and elemental analyses techniques. Single crystal X-ray diffraction analysis indicates that complexes 1 and 2 are isomorphous and isostructural, and crystallize in the triclinic system and P-1 space group. The Pd(II) or Pt(II) ions are four coordinated with four cyanide-carbon atoms in a square planar geometry. Cu(II) ion displays a distorted octahedral coordination by two N-atoms and two O-atoms of hmpH ligands, two bridging cyanide groups. In one dimensional structure of the complexes, [M(CN)4]2- (M = Pd(II) or Pt(II)) anions and [Cu(hmpH)2]2+ cations are linked via bridging cyanide ligands. In the complexes, the presence of intramolecular C-H⋯M (M = Pd(II) or Pt(II)) interactions with distance values of 3.00-2.95 Å are established, respectively.

  16. Visible light dynamical diffraction in a 1-D photonic crystal-based interferometer with an extremely thin spacer layer

    NASA Astrophysics Data System (ADS)

    Prudnikov, I. R.

    2016-01-01

    Properties of light diffraction in a Fabry-Pérot-like interferometer composed of two 1-D photonic crystals and a nanometer-thick spacer layer are analytically investigated. It is shown that the resonant enhancement of light wave intensity in such a layer is possible because of light dynamical diffraction from the photonic crystals of the interferometer. Numerical simulations of (i) light reflectivity and transmittance curves of the interferometer having an ultra-thin spacer layer (its thickness changes from less than 1 nm to about 10 nm) and (ii) the resonant distribution of the light wave intensity in the vicinity of the layer are performed. Based on the numerical simulations, potentialities for the determination of the structural parameters (e.g., thicknesses and refraction indexes) of ultra-thin spacer films are discussed. A difference is found to appear in resonant intensity enhancements inside the ultra-thin spacer layers between s- and p-polarized light waves.

  17. Synthesis, crystal structure, and properties of a 1-D terbium-substituted monolacunary Keggin-type polyoxotungstate.

    PubMed

    Ma, Pengtao; Si, Yanan; Wan, Rong; Zhang, Shaowei; Wang, Jingping; Niu, Jingyang

    2015-03-01

    A new 1-D linear chainlike terbium-substituted polyoxometalate [Tb(H2O)2(α-PW11O39)](4-) (1) has been synthesized in aqueous solution and characterized by elemental analysis, inductively coupled plasma atomic emission spectrometry (ICP-AES), X-ray powder diffraction (XRPD), IR spectrum, thermal analysis, electrospray ionization mass spectrometry (ESI-MS), and X-ray single-crystal diffraction. X-ray structural analysis reveals that 1 displays a 1-D linear chain containing [Tb(H2O)2(α-PW11O39)](4-) moieties. The Tb(III) cation incorporated into the monolacunary Keggin-type [α-PW11O39](7-) unit resides in a distorted monocapped triangular prismatic geometry and acts as a linker to join two adjacent [α-PW11O39](7-) units to form a 1-D chain structure. Solid-state photoluminescent property of 1 has been investigated at room temperature and the photoluminescent emission mainly results from the synergistic effect of the Tb(III) cation and the Na7[α-PW11O39] precursor. The ESI-MS spectrum of 1 confirms that the polyanion [Tb(H2O)(HPW11O39)](3-) is stable in aqueous solution.

  18. Quantum simulation of the cooperative Jahn-Teller transition in 1D ion crystals.

    PubMed

    Porras, Diego; Ivanov, Peter A; Schmidt-Kaler, Ferdinand

    2012-06-01

    The Jahn-Teller effect explains distortions and nondegenerate energy levels in molecular and solid-state physics via a coupling of effective spins to collective bosons. Here we propose and theoretically analyze the quantum simulation of a many-body Jahn-Teller model with linear ion crystals subjected to magnetic field gradients. We show that the system undergoes a quantum magnetic structural phase transition which leads to a reordering of particle positions and the formation of a spin-phonon quasicondensate in mesoscopic ion chains. PMID:23003971

  19. Band-edge lasing and miniband lasing in 1-D dual-periodic photonic crystal

    NASA Astrophysics Data System (ADS)

    Ying, Cui-Feng; Zhou, Wen-Yuan; Li, Yi; Ye, Qing; Zhang, Chun-Ping; Tian, Jian-Guo

    2012-06-01

    Herein, we report two different dual-periodic Photonic Crystals (PCs) in dichromated gelatin emulsion which are fabricated by four-beam holography and double-exposure holography. The minibands with high Q-factors have been evidently located in both two structures. By taking into account the non-uniform distribution of material, the numerical results agree quite well with the experimental results. We also compared the band-edge lasing in single-periodic PC and miniband lasing in Moiré dual-periodic PC. Due to extremely flat dispersion and large mode volume of the miniband, high optical conversion efficiency in miniband lasing is achieved as compared with that of band-edge lasing. Such effect may provide potential applications in low-threshold lasers and ultra-sensitive fluorescent probes in biological assays.

  20. Surface and confined acoustic waves in finite size 1D solid-fluid phononic crystals

    NASA Astrophysics Data System (ADS)

    El Hassouani, Y.; El Boudouti, E. H.; Djafari-Rouhani, B.; Rais, R.

    2007-12-01

    Using a Green's function method, we investigate theoretically the eigenmodes of a finite one-dimensional phononic crystal (superlattice) composed of N alternating layers of an elastic solid and an ideal fluid. If the finite superlattice is free of stress on both sides, we show that there are always N-1 modes in the allowed bands whereas there is one and only one mode corresponding to each band gap. This mode is either a surface mode in the band gap or a constant-frequency confined band-edge mode. If the finite superlattice is bounded from one side by a homogeneous fluid whereas the other surface is kept free, then an incident phonon from the fluid is perfectly reflected, however this reflection takes place with a large delay time if the frequency of the incident phonon coincides with the eigenfrequency of a surface mode

  1. Crystal Structures of Human TBC1D1 and TBC1D4 (AS160) RabGTPase-activating Protein (RabGAP) Domains Reveal Critical Elements for GLUT4 Translocation

    SciTech Connect

    S Park; W Jin; S Shoelson

    2011-12-31

    We have solved the x-ray crystal structures of the RabGAP domains of human TBC1D1 and human TBC1D4 (AS160), at 2.2 and 3.5 {angstrom} resolution, respectively. Like the yeast Gyp1p RabGAP domain, whose structure was solved previously in complex with mouse Rab33B, the human TBC1D1 and TBC1D4 domains both have 16 {alpha}-helices and no {beta}-sheet elements. We expected the yeast Gyp1p RabGAP/mouse Rab33B structure to predict the corresponding interfaces between cognate mammalian RabGAPs and Rabs, but found that residues were poorly conserved. We further tested the relevance of this model by Ala-scanning mutagenesis, but only one of five substitutions within the inferred binding site of the TBC1D1 RabGAP significantly perturbed catalytic efficiency. In addition, substitution of TBC1D1 residues with corresponding residues from Gyp1p did not enhance catalytic efficiency. We hypothesized that biologically relevant RabGAP/Rab partners utilize additional contacts not described in the yeast Gyp1p/mouse Rab33B structure, which we predicted using our two new human TBC1D1 and TBC1D4 structures. Ala substitution of TBC1D1 Met{sup 930}, corresponding to a residue outside of the Gyp1p/Rab33B contact, substantially reduced catalytic activity. GLUT4 translocation assays confirmed the biological relevance of our findings. Substitutions with lowest RabGAP activity, including catalytically dead RK and Met{sup 930} and Leu{sup 1019} predicted to perturb Rab binding, confirmed that biological activity requires contacts between cognate RabGAPs and Rabs beyond those in the yeast Gyp1p RabGAP/mouse Rab33B structure.

  2. Analysis of an electro-optic modulator based on a graphene-silicon hybrid 1D photonic crystal nanobeam cavity.

    PubMed

    Pan, Ting; Qiu, Ciyuan; Wu, Jiayang; Jiang, Xinhong; Liu, Boyu; Yang, Yuxing; Zhou, Huanying; Soref, Richard; Su, Yikai

    2015-09-01

    We propose and numerically study an on-chip graphene-silicon hybrid electro-optic (EO) modulator operating at the telecommunication band, which is implemented by a compact 1D photonic crystal nanobeam (PCN) cavity coupled to a bus waveguide with a graphene sheet on top. Through electrically tuning the Fermi level of the graphene, both the quality factor and the resonance wavelength can be significantly changed, thus the in-plane lightwave can be efficiently modulated. Based on finite-difference time-domain (FDTD) simulation results, the proposed modulator can provide a large free spectral range (FSR) of 125.6 nm, a high modulation speed of 133 GHz, and a large modulation depth of ~12.5 dB in a small modal volume, promising a high performance EO modulator for wavelength-division multiplexed (WDM) optical communication systems.

  3. Mode stability in photonic-crystal surface-emitting lasers with large κ{sub 1D}L

    SciTech Connect

    Liang, Yong Okino, Tsuyoshi; Ishizaki, Kenji; Noda, Susumu; Kitamura, Kyoko; Peng, Chao

    2014-01-13

    We study mode stability in photonic-crystal surface-emitting lasers (PCSELs) with large coupling-coefficient-length product κ{sub 1D}L(>6). We observe that mode competition occurs at high current levels above threshold. Our combined experimental and theoretical study provides the first evidence of the mode competition originating from the high-order band-edge modes. The decreased threshold margin between these competing high-order modes and the main lasing mode with increasing cavity length as well as the spatial hole burning effect may deteriorate the single-mode stability. Our finding is essential for designing single-mode high-power PCSELs for which the strategy to suppress the high-order modes must be considered.

  4. Selectivity, cycling stability and temperature dependence of touchless finger motion tracking devices based on 1D photonic crystals

    NASA Astrophysics Data System (ADS)

    Szendrei, Katalin; Ganter, Pirmin; Lotsch, Bettina V.

    2016-04-01

    We report on the humidity-induced swelling behavior of thin film devices composed of 2D phosphatoantimonate nanosheets and study their water uptake mechanism by means of ellipsometric porosimetry. Ambient humidity changes cause significant swelling in thin films composed of turbostratically disordered H3Sb3P2O14 nanosheets through water uptake between the nanosheet layers. This phenomenon is exploited to construct humidity responsive colorimetric sensors based on 1D Photonic Crystals. We demonstrate the ultrahigh sensitivity of H3Sb3P2O14/SiO2 Bragg stacks to ambient humidity, as well as reversible transparency switching as a consequence of refractive index matching at high relative humidities. The Photonic Crystals show substantially higher sensitivity to humidity as compared to ethanol vapor, reflecting the less favorable interaction of ethanol with the nanosheet layers as compared to water. Based on their ultrahigh sensitivity to humidity, phosphatoantimonate nanosheet based Bragg stacks can be used to track the motion of a finger by responding to its humidity sheath, without the finger touching the sensor surface. The cycling stability of such optical touchless positioning interfaces as well as the reversibility of the sensing event was demonstrated for more than 100 cycles. While the dew point presents an inherent lower limit to the sensor performance, the sensing ability remains essentially unaffected at elevated temperatures up to 40 °C.

  5. Co-crystal engineering: a novel method to obtain one-dimensional (1D) carbon nanocrystals of corannulene-fullerene by a solution process.

    PubMed

    Wang, Yu; Li, Yang; Zhu, Weigang; Liu, Jinyu; Zhang, Xiaotao; Li, Rongjin; Zhen, Yonggang; Dong, Huanli; Hu, Wenping

    2016-08-11

    In this study, 1D nanocrystals composed of C60 and corannulene were synthesized efficiently through cocrystallization by a solution process. These 1D nanocrystals display high electron transport characteristics of up to 0.11 cm(2) V(-1) s(-1) and good photoresponse of 0.09 A W(-1), indicating their potential applications in optoelectronics. The results suggest that co-crystal engineering provides a novel strategy for the rational design of new carbon-based crystalline nanomaterials. PMID:27480136

  6. Numerical study and topology optimization of 1D periodic bimaterial phononic crystal plates for bandgaps of low order Lamb waves.

    PubMed

    Hedayatrasa, Saeid; Abhary, Kazem; Uddin, Mohammad

    2015-03-01

    The optimum topology of bimaterial phononic crystal (PhCr) plates with one-dimensional (1D) periodicity to attain maximum relative bandgap width of low order Lamb waves is computationally investigated. The evolution of optimized topology with respect to filling fraction of constituents, alternatively stiff scattering inclusion, is explored. The underlying idea is to develop PhCr plate structures with high specific bandgap efficiency at particular filling fraction, or further with multiscale functionality through gradient of optimized PhCr unitcell all over the lattice array. Multiobjective genetic algorithm (GA) is employed in this research in conjunction with finite element method (FEM) for topology optimization of silicon-tungsten PhCr plate unitcells. A specialized FEM model is developed and verified for dispersion analysis of plate waves and calculation of modal response. Modal band structure of regular PhCr plate unitcells with centric scattering layer is studied as a function of aspect ratio and filling fraction. Topology optimization is then carried out for a few aspect ratios, with and without prescribed symmetry, over various filling fractions. The efficiency of obtained solutions is verified as compared to corresponding regular centric PhCr plate unitcells. Moreover, being inspired by the obtained optimum topologies, definite and easy to produce topologies are proposed with enhanced bandgap efficiency as compared to centric unitcells. Finally a few cases are introduced to evaluate the frequency response of finite PhCr plate structures produced by achieved topologies and also to confirm the reliability of calculated modal band structures. Cases made by consecutive unitcells of different filling fraction are examined in order to attest the bandgap efficiency and multiscale functionality of such graded PhCr plate structures.

  7. Thermomagnetic writing into magnetophotonic microcavities controlling thermal diffusion for volumetric magnetic holography.

    PubMed

    Isogai, Ryosuke; Nakamura, Yuichi; Takagi, Hiroyuki; Goto, Taichi; Lim, Pang Boey; Inoue, Mitsuteru

    2016-01-11

    Holographic memory is expected to become a high-capacity data storage. Magnetic volumetric holograms are rewritable holograms that are recorded as magnetization directions through thermomagnetic recording. However, the effective depth of magnetic holograms is limited by thermal diffusion that causes merging of magnetic fringes. In this study, we propose the insertion of heat-sink layers (HSLs) for retaining well-defined magnetic fringes during volumetric writing. Magnetophotonic microcavity media were used for demonstrating the HSL effect, and the structural design principle was established in numerical calculations. The results indicate that deep and clear magnetic fringes and an improvement in the diffraction efficiency can be achieved by the insertion of HSLs.

  8. 1D zigzag chain and 0D monomer Cd(II)/Zn(II) compounds based on flexible phenylenediacetic ligand: Synthesis, crystal structures and fluorescent properties

    NASA Astrophysics Data System (ADS)

    Yang, Fang; Ren, Yixia; Li, Dongsheng; Fu, Feng; Qi, Guangcai; Wang, Yaoyu

    2008-12-01

    Three novel Cd(II)/Zn(II) compounds, [Cd 2(poda) 2(phen) 3(H 2O)] n· nEtOH·3 nH 2O (1), [Zn(poda) 2(bpy)(H 2O)] n(2) and [Zn(Hpoda) 2(bpy)] (3) (H 2poda = 1,2-phenylenediacetic acid, phen = 1,10-phenanthroline, bpy = 2,2'-bipyridyl), have been synthesized and characterized by IR, TG, fluorescent spectrum and single-crystal X-ray diffraction techniques. In 1, poda 2- anions link the adjacent Cd(II) centers to generate a 1D zigzag chain. Furthermore, an unprecedented four-footed "8-shaped" mixed water-ethanol (H 2O) 6(C 2H 5OH) 2 cluster connects four double chains based on 1D zigzag chain into 3D supramolecular architecture. By bis(chelate-monodentate) fashion of poda 2- ligand, compound 2 exhibits 1D zigzag chains, which forming a dense zipper-like 2D structure via strong π-π stacking interactions. Differed from 1 and 2, compound 3 has a mononuclear motif, and displays a 3D 6-connected α-Po net hydrogen-bonded topology. The structure-related solid-state fluorescence spectra of compounds 1 and 2 have been determined.

  9. Syntheses, crystal structures and properties of two 1-D cadmium(II) coordination polymers based on 1,1'-(1,3-propanediyl)bis-1H-benzimidazole

    SciTech Connect

    Yang Huaixia; Meng Xiangru; Liu Yun; Hou Hongwei Fan Yaoting; Shen Xiaoqing

    2008-09-15

    The combination of framework-builders 1,1'-(1,3-propanediyl)bis-1H-benzimidazole (pbbm), Cd(II) ion and framework-regulator ClO{sub 4}{sup -} or SO{sub 4}{sup 2-} provides two new coordination polymers [Cd(pbbm){sub 2}(ClO{sub 4}){sub 2}]{sub n}(1) and {l_brace}[Cd(pbbm)SO{sub 4}(H{sub 2}O){sub 2}].CH{sub 3}OH{r_brace}{sub n}(2). Both of them display 1-D chain framework, but their detailed structures are clearly different from each other. 1 displays a 1-D ribbon of rings framework, 2 features an interesting infinite 1-D looped chain structure composed of two kinds of rings, the smaller 8-membered ring and the larger 20-membered ring. The antimicrobial activities of the two polymers were tested by the agar diffusion method and the results indicated that they exhibited antimicrobial activities against bacterial strands. The measurement of the non-isothermal kinetics of the thermal decomposition of 2 reveals that there are at least three steps that occur in its decomposition process. - Graphical abstract: Two new Cd(II)-containing complexes have been synthesized and characterized by single-crystal X-ray diffraction. The antimicrobial activity and the non-isothermal kinetics of the thermal decomposition of the polymers were also investigated. Display Omitted.

  10. Crystal structure of 7,8,9,10-tetra-hydro-benzo[b]naphtho-[2,1-d]furan.

    PubMed

    Wu, Zhongyuan; Reetz, Manfred T; Harms, Klaus

    2016-01-01

    In the title compound, C16H14O, the cyclo-hexene ring has a half-chair conformation. The mean plane, calculated through all non-H atoms of the mol-ecule, except for the central CH2 atoms of the cyclo-hexene ring, which deviate by 0.340 (3) and -0.369 (3) Å from this mean plane, has an r.m.s. deviation of 0.012 Å. In the crystal, there are C-H⋯π contacts present, resulting in the formation of zigzag chains propagating along the [010] direction. PMID:26870597

  11. Synthesis, crystal structures, magnetic and luminescent properties of unique 1D p-ferrocenylbenzoate-bridged lanthanide complexes

    SciTech Connect

    Yan, P.F.; Zhang, F.M.; Li, G.M.; Zhang, J.W.; Sun, W.B.; Suda, M.; Einaga, Y.

    2009-07-15

    Treatments of p-ferrocenylbenzoate [p-NaOOCH{sub 4}C{sub 6}Fc, Fc=(eta{sup 5}-C{sub 5}H{sub 5})Fe(eta{sup 5}-C{sub 5}H{sub 4})] with Ln(NO{sub 3}){sub 3}.nH{sub 2}O afford seven p-ferrocenylbenzoate lanthanide complexes {l_brace}[Ln(OOCH{sub 4}C{sub 6}Fc){sub 2}(mu{sub 2}-OOCH{sub 4}C{sub 6}Fc){sub 2}(H{sub 2}O){sub 2}](H{sub 3}O){r_brace}{sub n} [Ln=Ce (1), Pr (2), Sm (3), Eu (4), Gd (5), Tb (6) and Dy (7)]. X-ray crystallographic analysis reveals that the isomorphous complexes {l_brace}[Ce(OOCH{sub 4}C{sub 6}Fc){sub 2}(mu{sub 2}-OOCH{sub 4}C{sub 6}Fc){sub 2}(H{sub 2}O){sub 2}](H{sub 3}O){r_brace}{sub n} (1) and {l_brace}[Pr(OOCH{sub 4}C{sub 6}Fc){sub 2}(mu{sub 2}-OOCH{sub 4}C{sub 6}Fc){sub 2}(H{sub 2}O){sub 2}](H{sub 3}O){r_brace}{sub n} (2) form a unique 1D double-bridged infinite chain structure bridged by mu{sub 2}-OOCH{sub 4}C{sub 6}Fc groups. Each Ln(III) ion adopts a dodecahedron coordination environment with eight coordinated oxygen atoms from two terminal monodentate coordinated FcC{sub 6}H{sub 4}COO{sup -} units, two terminal monodentate coordinated H{sub 2}O molecules and four mu{sub 2}-{sup -}OOCH{sub 4}C{sub 6}Fc units. The luminescent spectra reveal that only 4 and 6 exhibit characteristic emissions of lanthanide ions, Eu(III) and Tb(III) ions, respectively. The variable-temperature magnetic properties of 5 and 7 suggest that a ferromagnetic coupling between spin carriers may exist in 5. - Graphical abstract: Seven p-ferrocenylbenzoate lanthanide coordination polymers were synthesized. Given is the perspective view of a unique 1D double-bridged infinite chain structure of 1, excitation and emission spectra of 6 and plots of chi{sub m}T vs. T and chi{sub m}{sup -1} vs. T of 5.

  12. Focus modulation of cylindrical vector beams by using 1D photonic crystal lens with negative refraction effect.

    PubMed

    Xu, Ji; Zhong, Yi; Wang, Shengming; Lu, Yunqing; Wan, Hongdan; Jiang, Jian; Wang, Jin

    2015-10-19

    Sub-wavelength focusing of cylindrical vector beams (CVBs) has attracted great attention due to the specific physical effects and the applications in many areas. More powerful, flexible and effective ways to modulate the focus transversally and also longitudinally are always being pursued. In this paper, cylindrically symmetric lens composed of negative-index one-dimensional photonic crystal is proposed to make a breakthrough. By revealing the relationship between focal length and the exit surface shape of the lens, a quite simple and effective principle of designing the lens structure is presented to realize specific focus modulation. Plano-concave lenses are parameterized to modulate the focal length and the number of focuses. An axicon constructed by one-dimensional photonic crystal is proposed for the first time to obtain a large depth of focus and an optical needle focal field with almost a theoretical minimum FWHM of 0.362λ is achieved under radially polarized incident light. Because of the almost identical negative refractive index for TE and TM polarization states, all the modulation methods can be applied for any arbitrary polarized CVBs. This work offers a promising methodology for designing negative-index lenses in related application areas. PMID:26480359

  13. Effects of loss factors on zero permeability and zero permittivity gaps in 1D photonic crystal containing DNG materials

    NASA Astrophysics Data System (ADS)

    Aghajamali, Alireza; Alamfard, Tannaz; Barati, Mahmood

    2014-12-01

    The effects of electric and magnetic loss factors on zero-= and zero-= gaps in a one-dimensional lossy photonic crystal composed of double-negative and double-positive materials are theoretically investigated by employing the characteristic matrix method. This study contradicts the previous reports as it indicates that by applying the inevitable factors of electric and magnetic losses to the double-negative material, the zero-= and zero-= gaps appear simultaneously in the transmission spectrum, being independent of the incidence angle and polarizations. Moreover, the results show that these gaps appear not only for an oblique incidence but also in the case of normal incidence, and their appearance at the normal incidence is directly related to the magnetic and electric loss factors. Besides, the results indicate that as the loss factors and angle of incidence increase, the width of both gaps also increases.

  14. Thermomagnetic writing into magnetophotonic microcavities controlling thermal diffusion for volumetric magnetic holography.

    PubMed

    Isogai, Ryosuke; Nakamura, Yuichi; Takagi, Hiroyuki; Goto, Taichi; Lim, Pang Boey; Inoue, Mitsuteru

    2016-01-11

    Holographic memory is expected to become a high-capacity data storage. Magnetic volumetric holograms are rewritable holograms that are recorded as magnetization directions through thermomagnetic recording. However, the effective depth of magnetic holograms is limited by thermal diffusion that causes merging of magnetic fringes. In this study, we propose the insertion of heat-sink layers (HSLs) for retaining well-defined magnetic fringes during volumetric writing. Magnetophotonic microcavity media were used for demonstrating the HSL effect, and the structural design principle was established in numerical calculations. The results indicate that deep and clear magnetic fringes and an improvement in the diffraction efficiency can be achieved by the insertion of HSLs. PMID:26832282

  15. Modeling of a wide band pass optical filter based on 1D ternary dielectric-metallic-dielectric photonic crystals

    NASA Astrophysics Data System (ADS)

    Rafat, Nadia H.; El-Naggar, Sahar A.; Mostafa, Samia I.

    2011-08-01

    We suggest ternary structures of dielectric-metal-dielectric photonic structures to be used as optical band pass filters. We theoretically study and evaluate the optical properties of these one-dimensional structures. ZnSe/metal/LiF and SiC/metal/SiO2 with three metals, namely silver, gold and copper, are suggested as the optical filters. We calculated the reflectance and the transmittance of electromagnetic waves (EMW) out of these structures using the transfer matrix method. These calculations take place for the case of normal and oblique incidences using actual measured values for the indices of refraction. Our calculations show that such photonic crystal (PC) filters have a well shaped pass band in the visible range and block efficiently ultraviolet and infrared EMW. Our results show that PCs having silver as the metal layer are preferred to those having gold and copper because of the high transmittance in the visible range. A SiC/Ag/SiO2 filter shows better performance than a ZnSe/Ag/LiF one from the transmittance and the shape of the band points of view. Such a filter shows a well shaped wide band over the range of incident angles from 0° to 80°.

  16. Silicon on-chip 1D photonic crystal nanobeam bandstop filters for the parallel multiplexing of ultra-compact integrated sensor array.

    PubMed

    Yang, Daquan; Wang, Chuan; Ji, Yuefeng

    2016-07-25

    We propose a novel multiplexed ultra-compact high-sensitivity one-dimensional (1D) photonic crystal (PC) nanobeam cavity sensor array on a monolithic silicon chip, referred to as Parallel Integrated 1D PC Nanobeam Cavity Sensor Array (PI-1DPC-NCSA). The performance of the device is investigated numerically with three-dimensional finite-difference time-domain (3D-FDTD) technique. The PI-1DPC-NCSA consists of multiple parallel-connected channels of integrated 1D PC nanobeam cavities/waveguides with gap separations. On each channel, by connecting two additional 1D PC nanobeam bandstop filters (1DPC-NBFs) to a 1D PC nanobeam cavity sensor (1DPC-NCS) in series, a transmission spectrum with a single targeted resonance is achieved for the purpose of multiplexed sensing applications. While the other spurious resonances are filtered out by the stop-band of 1DPC-NBF, multiple 1DPC-NCSs at different resonances can be connected in parallel without spectrum overlap. Furthermore, in order for all 1DPC-NCSs to be integrated into microarrays and to be interrogated simultaneously with a single input/output port, all channels are then connected in parallel by using a 1 × n taper-type equal power splitter and a n × 1 S-type power combiner in the input port and output port, respectively (n is the channel number). The concept model of PI-1DPC-NCSA is displayed with a 3-parallel-channel 1DPC-NCSs array containing series-connected 1DPC-NBFs. The bulk refractive index sensitivities as high as 112.6nm/RIU, 121.7nm/RIU, and 148.5nm/RIU are obtained (RIU = Refractive Index Unit). In particular, the footprint of the 3-parallel-channel PI-1DPC-NCSA is 4.5μm × 50μm (width × length), decreased by more than three orders of magnitude compared to 2D PC integrated sensor arrays. Thus, this is a promising platform for realizing ultra-compact lab-on-a-chip applications with high integration density and high parallel-multiplexing capabilities. PMID:27464080

  17. Unique 1D Co3O4 crystallized nanofibers with (220) oriented facets as high-performance lithium ion battery anode material

    NASA Astrophysics Data System (ADS)

    Tan, Yanli; Gao, Qiuming; Li, Zeyu; Tian, Weiqian; Qian, Weiwei; Yang, Chunxiao; Zhang, Hang

    2016-05-01

    A novel one-step hydrothermal and calcination strategy was developed to synthesize the unique 1D oriented Co3O4 crystal nanofibers with (220) facets on the carbon matrix derived from the natural, abundant and low cost wool fibers acting as both carbon precursor and template reagent. The resultant W2@Co3O4 nanocomposite exhibited very high specific capacity and favorable high-rate capability when used as anode material of lithium ion battery. The high reversible Li+ ion storage capacity of 986 mAh g‑1 was obtained at 100 mA g‑1 after 150 cycles, higher than the theoretical capacity of Co3O4 (890 mAh g‑1). Even at the higher current density of 1 A g‑1, the electrode could still deliver a remarkable discharge capacity of 720 mAh g‑1 over 150 cycles.

  18. Unique 1D Co3O4 crystallized nanofibers with (220) oriented facets as high-performance lithium ion battery anode material

    PubMed Central

    Tan, Yanli; Gao, Qiuming; Li, Zeyu; Tian, Weiqian; Qian, Weiwei; Yang, Chunxiao; Zhang, Hang

    2016-01-01

    A novel one-step hydrothermal and calcination strategy was developed to synthesize the unique 1D oriented Co3O4 crystal nanofibers with (220) facets on the carbon matrix derived from the natural, abundant and low cost wool fibers acting as both carbon precursor and template reagent. The resultant W2@Co3O4 nanocomposite exhibited very high specific capacity and favorable high-rate capability when used as anode material of lithium ion battery. The high reversible Li+ ion storage capacity of 986 mAh g−1 was obtained at 100 mA g−1 after 150 cycles, higher than the theoretical capacity of Co3O4 (890 mAh g−1). Even at the higher current density of 1 A g−1, the electrode could still deliver a remarkable discharge capacity of 720 mAh g−1 over 150 cycles. PMID:27217201

  19. Crystal Structure of Human Liver delta {4}-3-Ketosteroid 5 beta-Reductase (AKR1D1) and Implications for Substrate Binding and Catalysis

    SciTech Connect

    Di Costanzo,L.; Drury, J.; Penning, T.; Christianson, D.

    2008-01-01

    AKR1D1 (steroid 5{beta}-reductase) reduces all 4-3-ketosteroids to form 5{beta}-dihydrosteroids, a first step in the clearance of steroid hormones and an essential step in the synthesis of all bile acids. The reduction of the carbon-carbon double bond in an a,{beta}-unsaturated ketone by 5{beta}-reductase is a unique reaction in steroid enzymology because hydride transfer from NADPH to the {beta}-face of a 4-3-ketosteroid yields a cis-A/B-ring configuration with an {approx}90 bend in steroid structure. Here, we report the first x-ray crystal structure of a mammalian steroid hormone carbon-carbon double bond reductase, human 4-3-ketosteroid 5{beta}-reductase (AKR1D1), and its complexes with intact substrates. We have determined the structures of AKR1D1 complexes with NADP+ at 1.79- and 1.35- Angstroms resolution (HEPES bound in the active site), NADP+ and cortisone at 1.90- Angstroms resolution, NADP+ and progesterone at 2.03- Angstroms resolution, and NADP+ and testosterone at 1.62- Angstroms resolution. Complexes with cortisone and progesterone reveal productive substrate binding orientations based on the proximity of each steroid carbon-carbon double bond to the re-face of the nicotinamide ring of NADP+. This orientation would permit 4-pro-(R)-hydride transfer from NADPH. Each steroid carbonyl accepts hydrogen bonds from catalytic residues Tyr58 and Glu120. The Y58F and E120A mutants are devoid of activity, supporting a role for this dyad in the catalytic mechanism. Intriguingly, testosterone binds nonproductively, thereby rationalizing the substrate inhibition observed with this particular steroid. The locations of disease-linked mutations thought to be responsible for bile acid deficiency are also revealed.

  20. Syntheses, crystal structures, and characterization of three 1D, 2D and 3D complexes based on mixed multidentate N- and O-donor ligands

    SciTech Connect

    Yang, Huai-Xia; Liang, Zhen; Hao, Bao-Lian; Meng, Xiang-Ru

    2014-10-15

    Three new 1D to 3D complexes, namely, ([Ni(btec)(Himb){sub 2}(H{sub 2}O){sub 2}]·6H{sub 2}O){sub n} (1), ([Cd(btec){sub 0.5}(imb)(H{sub 2}O)]·1.5H{sub 2}O){sub n} (2), and ([Zn(btec){sub 0.5}(imb)]·H{sub 2}O){sub n} (3) (H{sub 4}btec=1,2,4,5-benzenetetracarboxylic acid, imb=2-(1H-imidazol-1-methyl)-1H-benzimidazole) have been synthesized by adjusting the central metal ions. Single-crystal X-ray diffraction analyses reveal that complex 1 possesses a 1D chain structure which is further extended into the 3D supramolecular architecture via hydrogen bonds. Complex 2 features a 2D network with Schla¨fli symbol (5{sup 3}·6{sup 2}·7)(5{sup 2}·6{sup 4}). Complex 3 presents a 3D framework with a point symbol of (4·6{sup 4}·8)(4{sup 2}·6{sup 2}·8{sup 2}). Moreover, their IR spectra, PXRD patterns, thermogravimetric curves, and luminescent emissions were studied at room temperature. - Graphical abstract: Three new 1D to 3D complexes with different structural and topological motifs have been obtained by modifying the central metal ions. Additionally, their IR, TG analyses and fluorescent properties are also investigated. - Highlights: • Three complexes based on mixed multidentate N- and O-donor ligands. • The complexes are characterized by IR, luminescence and TGA techniques. • Benzenetetracarboxylates display different coordination modes in complexes 1–3. • Changing the metal ions can result in complexes with completely different structures.

  1. Syntheses, crystal structures, and characterization of three 1D, 2D and 3D complexes based on mixed multidentate N- and O-donor ligands

    NASA Astrophysics Data System (ADS)

    Yang, Huai-Xia; Liang, Zhen; Hao, Bao-Lian; Meng, Xiang-Ru

    2014-10-01

    Three new 1D to 3D complexes, namely, {[Ni(btec)(Himb)2(H2O)2]·6H2O}n (1), {[Cd(btec)0.5(imb)(H2O)]·1.5H2O}n (2), and {[Zn(btec)0.5(imb)]·H2O}n (3) (H4btec=1,2,4,5-benzenetetracarboxylic acid, imb=2-(1H-imidazol-1-methyl)-1H-benzimidazole) have been synthesized by adjusting the central metal ions. Single-crystal X-ray diffraction analyses reveal that complex 1 possesses a 1D chain structure which is further extended into the 3D supramolecular architecture via hydrogen bonds. Complex 2 features a 2D network with Schla¨fli symbol (53·62·7)(52·64). Complex 3 presents a 3D framework with a point symbol of (4·64·8)(42·62·82). Moreover, their IR spectra, PXRD patterns, thermogravimetric curves, and luminescent emissions were studied at room temperature.

  2. Crystal Structure of Human Liver [delta][superscript 4]-3-Ketosteroid 5[beta]-Reductase (AKR1D1) and Implications for Substrate Binding and Catalysis

    SciTech Connect

    Di Costanzo, Luigi; Drury, Jason E.; Penning, Trevor M.; Christianson, David W.

    2008-07-15

    AKR1D1 (steroid 5{beta}-reductase) reduces all {Delta}{sup 4}-3-ketosteroids to form 5{beta}-dihydrosteroids, a first step in the clearance of steroid hormones and an essential step in the synthesis of all bile acids. The reduction of the carbon-carbon double bond in an {alpha}{beta}-unsaturated ketone by 5{beta}-reductase is a unique reaction in steroid enzymology because hydride transfer from NADPH to the {beta}-face of a {Delta}{sup 4}-3-ketosteroid yields a cis-A/B-ring configuration with an {approx}90{sup o} bend in steroid structure. Here, we report the first x-ray crystal structure of a mammalian steroid hormone carbon-carbon double bond reductase, human {Delta}{sup 4}-3-ketosteroid 5{beta}-reductase (AKR1D1), and its complexes with intact substrates. We have determined the structures of AKR1D1 complexes with NADP{sup +} at 1.79- and 1.35-{angstrom} resolution (HEPES bound in the active site), NADP{sup +} and cortisone at 1.90-{angstrom} resolution, NADP{sup +} and progesterone at 2.03-{angstrom} resolution, and NADP{sup +} and testosterone at 1.62-{angstrom} resolution. Complexes with cortisone and progesterone reveal productive substrate binding orientations based on the proximity of each steroid carbon-carbon double bond to the re-face of the nicotinamide ring of NADP{sup +}. This orientation would permit 4-pro-(R)-hydride transfer from NADPH. Each steroid carbonyl accepts hydrogen bonds from catalytic residues Tyr{sup 58} and Glu{sup 120}. The Y58F and E120A mutants are devoid of activity, supporting a role for this dyad in the catalytic mechanism. Intriguingly, testosterone binds nonproductively, thereby rationalizing the substrate inhibition observed with this particular steroid. The locations of disease-linked mutations thought to be responsible for bile acid deficiency are also revealed.

  3. Dicynamide bridged two new zig-zag 1-D Zn(II) coordination polymers of pyrimidine derived Schiff base ligands: Synthesis, crystal structures and fluorescence studies

    NASA Astrophysics Data System (ADS)

    Konar, Saugata

    2015-07-01

    Two new zigzag 1-D polymeric Zn(II) coordination polymers {[Zn(L1)(μ1,5-dca)](H2O)}n (1), {[Zn(L2)(μ1,5-dca)](ClO4)}n (2) of two potentially tridentate NNO-, NNN-, donor Schiff base ligands [2-(2-(4,6-dimethylpyrimidin-2-yl)hydrazono)methyl)phenol] (L1), [1-(4,6-dimethylpyrimidin-2-yl)-2-(dipyridin-2ylmethylene)hydrazine] (L2) have been synthesized and characterized by elemental analyses, IR and 1H NMR, fluorescence spectroscopy and single crystal X-ray crystallography. The dicyanamide ions act as linkers (μ1,5 mode) in the formation of these coordination polymers. Both the complexes 1 and 2 have same distorted square pyramidal geometry around the Zn(II) centres. The weak forces like π⋯π, Csbnd H⋯π, anion⋯π interactions lead to various supramolecular architectures. Complex 1 shows high chelation enhanced fluorescence compared to that of 2. The fluorescence spectral changes observed high selectivity towards Zn(II) over other metal ions such as Mn(II), Co(II), Ni(II), Cu(II).

  4. All-optical sensitive phase shifting based on nonlinear out-of-plane coupling through 1-D slab photonic crystal with a layer of graphene.

    PubMed

    Asadi, Reza; Ouyang, Zhengbiao; Yu, Quanqiang; Ruan, Shuangchen

    2014-06-16

    We realize all-optical sensitive phase shifting based on nonlinear out-of-plane coupling to a slab waveguide through Fano resonance of a slab 1-D photonic crystal (PhC). We use a graphene layer as the nonlinear material and change its refractive index by the input light intensity through Kerr nonlinear effect to obtain a shift in the Fano resonance frequency. The Fano resonance and self-focusing effect lead to light-intensity enhancement on the graphene in the PhC, reinforcing the nonlinear effect of refractive index in the graphene. Through finite-difference time-domain simulation, we demonstrate that the phase changing sensitivity obtained can be 4 orders higher than that by a single graphene under the same input light intensity. Moreover the threshold pump intensity for all-optical sensitive phase shifting in the coupled light to the waveguide is as low as ~4 MW per square centimeter. The results are applicable in micro optical integrated circuits for phase shifters, phase modulators, power limiters, and phase logic elements for optical computation, digital phase shift keying in communication systems, and non-contact sensitive signal detectors.

  5. New miniaturized exhaled nitric oxide sensor based on a high Q/V mid-infrared 1D photonic crystal cavity.

    PubMed

    Conteduca, D; Dell'Olio, F; Ciminelli, C; Armenise, M N

    2015-03-20

    A high Q/V mid-infrared 1D photonic crystal cavity in chalcogenide glass AMTIR-1 (Ge33As12Se55) resonating at λR=5.26  μm has been proposed as a key element of a sensor able to evaluate the nitric oxide (NO) concentration in the exhaled breath, namely fraction exhaled NO. The cavity design has been carried out through 3D finite-element method simulations. A Q-factor of 1.1×104 and a mode volume V=0.8  (λ/n)3, corresponding to a Q/V ratio of 1.4×104(λ/n)-3, have been obtained with a resonance transmission coefficient T=15%. A sensitivity of 10 ppb has been calculated with reference to the photothermal physical property of the material. Such a result is lower than the state-of-the-art of NO sensors proposed in literature, where hundreds of parts per trillion-level detection seem to have been achieved, but comparable with the performance obtained by commercial devices. The main advantages of the new device are in terms of footprint (=150  μm2), smaller at least 1 order of magnitude than those in literature, fast response time (only few seconds), and potential low cost. Such properties make possible in a handheld device the sensor integration in a multi-analysis system for detecting the presence of several trace gases, improving prevention, and reducing the duration of drug treatment for asthma and viral infections. PMID:25968502

  6. Syntheses, crystal structures and luminescent properties of two new 1D d {sup 1} coordination polymers constructed from 2,2'-bibenzimidazole and 1,4-benzenedicarboxylate

    SciTech Connect

    Wen Lili; Li Yizhi; Dang Dongbin; Tian Zhengfang; Ni Zhaoping; Meng Qingjin . E-mail: mengqj@nju.edu.cn

    2005-11-15

    Two novel interesting d {sup 1} metal coordination polymers, [Zn(H{sub 2}bibzim)(BDC)] {sub n} (1) and [Cd(H{sub 2}bibzim)(BDC)] {sub n} (2) [H{sub 2}bibzim=2,2'-bibenzimidazole, BDC=1,4-benzenedicarboxylate] have been synthesized under solvothermal conditions and structurally characterized. Both 1 and 2 are constructed from infinite neutral zigzag-like one-dimensional (1D) chains. The {pi}-{pi} interactions and interchain hydrogen-bonding interactions further extend the 1D arrangement to generate a 3D supramolecular architecture for 1 and 2. Both complexes have high thermal stability and display strong blue fluorescent emissions in the solid state upon photo-excitation at 365 nm at room temperature. They are the first two examples that 2,2'-bibenzimidazole has been introduced into the d {sup 1} coordination polymeric framework.

  7. Synthesis, characterization and crystal structure determination of Mn (II) ion based 1D polymer constructed from 2, 2‧ bipyridyl and azide group, its thermal stability, magnetic properties and Hirshfeld surface analysis

    NASA Astrophysics Data System (ADS)

    Mudsainiyan, R. K.; Jassal, Amanpreet Kaur; Chawla, S. K.

    2015-05-01

    The 1-D polymeric complex (I) is having formula [Mn(2,2‧-BP).(N3)2]n, which has been crystallized in distilled water and characterized by elemental analyses, FT-IR spectrum, powder X-ray diffraction analyses and single-crystal diffraction analysis. This polymer possesses 1D helical chains or coils where Mn-azide-Mn forms the base of the coil which is alternatively garlanded by rigid bi-pyridine rings, where coordinates are in anti-fashion. The Mn (II) ions in the repeating units are linked by two end-on azide groups which extend through the two end-to-end azide ligands to the next unit forming a 1-D polymeric chain. The present study suggests that the use of this rigid and neutral building block leads to give better arrangement of the polymeric motif with [010] chains in 2-c uninodal net. During investigation of strong or weak intermolecular interactions, X-ray diffraction analysis and Hirshfeld surface analysis give rise to comparable results but in Hirshfeld surface analysis, two-third times more results of close contacts are obtained. The fingerprint plots demonstrate that these weak non-bonding interactions are important for stabilizing the crystal packing. Magnetic properties of the complex (I) were analyzed on the basis of an alternating ferro- and antiferromagnetic Heisenberg chain of Mn (II) ions. The J-exchange parameters found are J1=64.3 K (45.3 cm-1), and J2=-75.7 K (-53.3 cm-1). Magnetic properties are discussed in comparison with those of other similar molecular magnets of [Mn(L-L)(N3)2]n type.

  8. Crystal structure of Vδ1 T cell receptor in complex with CD1d-sulfatide shows MHC-like recognition of a self-lipid by human γδ T cells.

    PubMed

    Luoma, Adrienne M; Castro, Caitlin D; Mayassi, Toufic; Bembinster, Leslie A; Bai, Li; Picard, Damien; Anderson, Brian; Scharf, Louise; Kung, Jennifer E; Sibener, Leah V; Savage, Paul B; Jabri, Bana; Bendelac, Albert; Adams, Erin J

    2013-12-12

    The nature of the antigens recognized by γδ T cells and their potential recognition of major histocompatibility complex (MHC)-like molecules has remained unclear. Members of the CD1 family of lipid-presenting molecules are suggested ligands for Vδ1 TCR-expressing γδ T cells, the major γδ lymphocyte population in epithelial tissues. We crystallized a Vδ1 TCR in complex with CD1d and the self-lipid sulfatide, revealing the unusual recognition of CD1d by germline Vδ1 residues spanning all complementarity-determining region (CDR) loops, as well as sulfatide recognition separately encoded by nongermline CDR3δ residues. Binding and functional analysis showed that CD1d presenting self-lipids, including sulfatide, was widely recognized by gut Vδ1+ γδ T cells. These findings provide structural demonstration of MHC-like recognition of a self-lipid by γδ T cells and reveal the prevalence of lipid recognition by innate-like T cell populations.

  9. Control of coupling in 1D photonic crystal coupled-cavity nano-wire structures via hole diameter and position variation

    NASA Astrophysics Data System (ADS)

    Zain, A. R. Md; De La Rue, R. M.

    2015-12-01

    We have successfully demonstrated close experimental control of the resonance splitting/free spectral range of a coupled micro-cavity one-dimensional photonic crystal/photonic wire device structure based on silicon-on-insulator. Clear splitting of the resonances, with FSR values ranging from 8 nm to 48 nm, was obtained through the use of different hole arrangements within the middle section of the device structures, between the coupled cavities. The results show good agreement with calculations obtained using a finite-difference time-domain simulation approach.

  10. Crystal structure of 7,8,9,10-tetra­hydro­benzo[b]naphtho­[2,1-d]furan

    PubMed Central

    Wu, Zhongyuan; Reetz, Manfred T.; Harms, Klaus

    2016-01-01

    In the title compound, C16H14O, the cyclo­hexene ring has a half-chair conformation. The mean plane, calculated through all non-H atoms of the mol­ecule, except for the central CH2 atoms of the cyclo­hexene ring, which deviate by 0.340 (3) and −0.369 (3) Å from this mean plane, has an r.m.s. deviation of 0.012 Å. In the crystal, there are C—H⋯π contacts present, resulting in the formation of zigzag chains propagating along the [010] direction. PMID:26870597

  11. Synthesis, characterization and crystal structure determination of Mn (II) ion based 1D polymer constructed from 2, 2′ bipyridyl and azide group, its thermal stability, magnetic properties and Hirshfeld surface analysis

    SciTech Connect

    Mudsainiyan, R.K. Jassal, Amanpreet Kaur; Chawla, S.K.

    2015-05-15

    The 1-D polymeric complex (I) is having formula [Mn(2,2′-BP).(N{sub 3}){sub 2}]{sub n}, which has been crystallized in distilled water and characterized by elemental analyses, FT-IR spectrum, powder X-ray diffraction analyses and single-crystal diffraction analysis. This polymer possesses 1D helical chains or coils where Mn–azide–Mn forms the base of the coil which is alternatively garlanded by rigid bi-pyridine rings, where coordinates are in anti-fashion. The Mn (II) ions in the repeating units are linked by two end-on azide groups which extend through the two end-to-end azide ligands to the next unit forming a 1-D polymeric chain. The present study suggests that the use of this rigid and neutral building block leads to give better arrangement of the polymeric motif with [010] chains in 2-c uninodal net. During investigation of strong or weak intermolecular interactions, X-ray diffraction analysis and Hirshfeld surface analysis give rise to comparable results but in Hirshfeld surface analysis, two-third times more results of close contacts are obtained. The fingerprint plots demonstrate that these weak non-bonding interactions are important for stabilizing the crystal packing. Magnetic properties of the complex (I) were analyzed on the basis of an alternating ferro- and antiferromagnetic Heisenberg chain of Mn (II) ions. The J-exchange parameters found are J{sub 1}=64.3 K (45.3 cm{sup −1}), and J{sub 2}=−75.7 K (−53.3 cm{sup −1}). Magnetic properties are discussed in comparison with those of other similar molecular magnets of [Mn(L–L)(N{sub 3}){sub 2}]{sub n} type. - - Highlights: • Synthesized 1-D polymeric complex of Mn (II) ions with 2, 2′ bipyridyl and azide group. • X-ray data of complex (I) is in a good agreement with TGA and other spectroscopic techniques. • DFT calculations were done and compared with the parameter of experimental and theoretical data. • Intermolecular interactions calculated by Hirshfeld surface analysis

  12. Synthesis, crystal structures and magnetic properties of mer-cyanideiron(III)-based 1D heterobimetallic cyanide-bridged chiral coordination polymers.

    PubMed

    Zhang, Daopeng; Zhuo, Shuping; Zhang, Hongyan; Wang, Ping; Jiang, Jianzhuang

    2015-03-14

    Two pairs of cyanide-bridged Fe(III)–Mn(III)/Cu(II) chiral enantiomer coordination polymers {[Mn(S,S/R,R-Salcy)(CH3OH)2]{[Mn(S,S/R,R-Salcy)][Fe(bbp)(CN)3]}}2n (1,2) (bbp = bis(2-benzimidazolyl)pyridine dianion) and {[Cu(S,S/R,R-Chxn)2]2[Fe2(tbbp)(CN)6]}n (3,4) (tbbp = tetra(3-benzimidazolyl)-4,4′-bipyridine tetraanion) have been successfully prepared by employing mer-tricyanometallate [PPh4]2[Fe(bbp)(CN)3] or the newly bimetallic mer-cyanideiron(III) precursor K4[Fe2(tbbp)(CN)6] as building blocks and with chiral manganese(III)/copper(II) compounds as assemble segments. The four complexes have been characterized by elemental analysis, IR spectroscopy, circular dichroism (CD) and magnetic circular dichroism (MCD) spectra. Single X-ray diffraction reveals that complexes 1 and 2 possess a single anionic chain structure consisting of the asymmetric chiral {[Mn(S,S/R,R-Salcy)][Fe(bbp)(CN)3]}2(2−) unit with free [Mn(S,S/R,R-Salcy)](+) as balanced cations. The cyanide-bridged Fe(III)–Cu(II) complexes 3 and 4 can be structurally characterized as neutral ladder-like double chains composed of the alternating cyanide-bridged Fe–Cu units. Our investigation of magnetic susceptibilities reveals the antiferromagnetic coupling between the cyanide-bridged Fe(III) and Mn(III)/Cu(II) ions for complexes 1–4. These results have been further confirmed by theoretical simulation through numerical matrix diagonalization techniques using a Fortran program or a uniform chain model, leading to the coupling constants J = −7.36 cm(−1), D = −1.52 cm(−1) (1) and J = −4.35 cm(−1) (3), respectively. PMID:25661782

  13. Near-infrared tunable narrow filter properties in a 1D photonic crystal containing semiconductor metamaterial photonic quantum-well defect

    NASA Astrophysics Data System (ADS)

    Barati, Mahmood; Aghajamali, Alireza

    2016-05-01

    The near-infrared (NIR) narrow filter properties in the transmission spectra of a one-dimensional photonic crystal doped with semiconductor metamaterial photonic quantum-well defect (PQW) were theoretically studied. The behavior of the defect mode as a function of the stack number of the PQW defect structure, the filling factor of semiconductor metamaterial layer, the polarization and the angle of incidence were investigated for Al-doped ZnO (AZO) and ZnO as the semiconductor metamaterial layer. It is found that the frequency of the defect mode can be tuned by variation of the period of the defect structure, polarization, incidence angle, and the filling factor of the semiconductor metamaterial layer. It is also shown that the number of the defect mode is independent of the period of the PQW defect structure and is in sharp contrast with the case where a common dielectric or metamaterial defect are used. The results also show that for both polarizations the defect mode is red-shifted as the number of the defect period and filling factor increase. An opposite trend is observed as the angle of incidence increases. The proposed structure could provide useful information for designing new types of tuneable narrowband filters at NIR region.

  14. Syntheses, crystal structure, spectroscopic and photoluminescence studies of mononuclear copper(II), manganese(II), cadmium(II), and a 1D polymeric Cu(II) complexes with a pyrimidine derived Schiff base ligand

    NASA Astrophysics Data System (ADS)

    Ray, Sangita; Konar, Saugata; Jana, Atanu; Das, Kinsuk; Dhara, Anamika; Chatterjee, Sudipta; Kar, Susanta Kumar

    2014-01-01

    The complexation behaviour of Schiff base ligand 2-((2-(4,6-dimethylpyrimidin-2-yl)hydrazono)methyl)phenol [HL] towards different metal centres is reported by the syntheses and characterization of three mononuclear Cu(II), Mn(II) and Cd(II) complexes, [Cu(L)(H2O)2](NO3)(H2O) (1), [Mn(L)2](CH3OH) (2), [Cd(L)2](CH3OH) (3) and a 1D polymeric Cu(II) complex, [Cu(L)(ClO4)(C2N2O2H)]n(CH3OH) (4) respectively. In the complexes 1-4 the deprotonated uninegative tridentate ligand serves as NNO donor where one pyrimidine ring N, the azomethine N and the salicyl hydroxyl oxygen atoms are coordinatively active. The complex 1 has almost square pyramidal geometry [τ = 0.2081] whereas the metal centres maintain distorted octahedral geometry in the remaining three complexes 2-4. All the complexes are characterized by X-ray crystallography. The Cd(II) complex has considerable fluorescence while the rest of the complexes and the ligand molecule are fluorescent silent.

  15. Upstream Design and 1D-CAE

    NASA Astrophysics Data System (ADS)

    Sawada, Hiroyuki

    Recently, engineering design environment of Japan is changing variously. Manufacturing companies are being challenged to design and bring out products that meet the diverse demands of customers and are competitive against those produced by rising countries(1). In order to keep and strengthen the competitiveness of Japanese companies, it is necessary to create new added values as well as conventional ones. It is well known that design at the early stages has a great influence on the final design solution. Therefore, design support tools for the upstream design is necessary for creating new added values. We have established a research society for 1D-CAE (1 Dimensional Computer Aided Engineering)(2), which is a general term for idea, methodology and tools applicable for the upstream design support, and discuss the concept and definition of 1D-CAE. This paper reports our discussion about 1D-CAE.

  16. DESIGN PACKAGE 1D SYSTEM SAFETY ANALYSIS

    SciTech Connect

    L.R. Eisler

    1995-02-02

    The purpose of this analysis is to systematically identify and evaluate hazards related to the Yucca Mountain Project Exploratory Studies Facility (ESF) Design Package 1D, Surface Facilities, (for a list of design items included in the package 1D system safety analysis see section 3). This process is an integral part of the systems engineering process; whereby safety is considered during planning, design, testing, and construction. A largely qualitative approach was used since a radiological System Safety analysis is not required. The risk assessment in this analysis characterizes the accident scenarios associated with the Design Package 1D structures/systems/components in terms of relative risk and includes recommendations for mitigating all identified risks. The priority for recommending and implementing mitigation control features is: (1) Incorporate measures to reduce risks and hazards into the structure/system/component (S/S/C) design, (2) add safety devices and capabilities to the designs that reduce risk, (3) provide devices that detect and warn personnel of hazardous conditions, and (4) develop procedures and conduct training to increase worker awareness of potential hazards, on methods to reduce exposure to hazards, and on the actions required to avoid accidents or correct hazardous conditions. The scope of this analysis is limited to the Design Package 1D structures/systems/components (S/S/Cs) during normal operations excluding hazards occurring during maintenance and ''off normal'' operations.

  17. 1D X-ray Beam Compressing Monochromators

    SciTech Connect

    Korytar, D.; Dobrocka, E.; Konopka, P.; Zaprazny, Z.; Ferrari, C.; Mikulik, P.; Vagovic, P.; Ac, V.; Erko, A.; Abrosimov, N.

    2010-04-06

    A total beam compression of 5 and 10 corresponding to the asymmetry angles of 9 deg. and 12 deg. is achieved with V-5 and V-10 monochromators, respectively, in standard single crystal pure germanium (220) X-ray beam compressing (V-shaped) monochromators for CuKalpha{sub 1} radiation. A higher 1D compression of X-ray beam is possible using larger angles of asymmetry, however it is achieved at the expense of the total intensity, which is decreased due to the refraction effect. To increase the monochromator intensity, several ways are considered both theoretically and experimentally. Linearly graded germanium rich Ge{sub x}Si{sub (1-x)} single crystal was used to prepare a V-21 single crystal monochromator with 15 deg. asymmetry angles (compression factor of 21). Its temperature gradient version is discussed for CuKalpha{sub 1} radiation. X-ray diffraction measurements on the graded GeSi monochromator showed more than 3-times higher intensity at the output compared with that of a pure Ge monochromator.

  18. Centrosome Positioning in 1D Cell Migration

    NASA Astrophysics Data System (ADS)

    Adlerz, Katrina; Aranda-Espinoza, Helim

    During cell migration, the positioning of the centrosome and nucleus define a cell's polarity. For a cell migrating on a two-dimensional substrate the centrosome is positioned in front of the nucleus. Under one-dimensional confinement, however, the centrosome is positioned behind the nucleus in 60% of cells. It is known that the centrosome is positioned by CDC42 and dynein for cells moving on a 2D substrate in a wound-healing assay. It is currently unknown, however, if this is also true for cells moving under 1D confinement, where the centrosome position is often reversed. Therefore, centrosome positioning was studied in cells migrating under 1D confinement, which mimics cells migrating through 3D matrices. 3 to 5 μm fibronectin lines were stamped onto a glass substrate and cells with fluorescently labeled nuclei and centrosomes migrated on the lines. Our results show that when a cell changes directions the centrosome position is maintained. That is, when the centrosome is between the nucleus and the cell's trailing edge and the cell changes direction, the centrosome will be translocated across the nucleus to the back of the cell again. A dynein inhibitor did have an influence on centrosome positioning in 1D migration and change of directions.

  19. 1D fast coded aperture camera.

    PubMed

    Haw, Magnus; Bellan, Paul

    2015-04-01

    A fast (100 MHz) 1D coded aperture visible light camera has been developed as a prototype for imaging plasma experiments in the EUV/X-ray bands. The system uses printed patterns on transparency sheets as the masked aperture and an 80 channel photodiode array (9 V reverse bias) as the detector. In the low signal limit, the system has demonstrated 40-fold increase in throughput and a signal-to-noise gain of ≈7 over that of a pinhole camera of equivalent parameters. In its present iteration, the camera can only image visible light; however, the only modifications needed to make the system EUV/X-ray sensitive are to acquire appropriate EUV/X-ray photodiodes and to machine a metal masked aperture. PMID:25933861

  20. 1D fast coded aperture camera.

    PubMed

    Haw, Magnus; Bellan, Paul

    2015-04-01

    A fast (100 MHz) 1D coded aperture visible light camera has been developed as a prototype for imaging plasma experiments in the EUV/X-ray bands. The system uses printed patterns on transparency sheets as the masked aperture and an 80 channel photodiode array (9 V reverse bias) as the detector. In the low signal limit, the system has demonstrated 40-fold increase in throughput and a signal-to-noise gain of ≈7 over that of a pinhole camera of equivalent parameters. In its present iteration, the camera can only image visible light; however, the only modifications needed to make the system EUV/X-ray sensitive are to acquire appropriate EUV/X-ray photodiodes and to machine a metal masked aperture.

  1. 1D-VAR Retrieval Using Superchannels

    NASA Technical Reports Server (NTRS)

    Liu, Xu; Zhou, Daniel; Larar, Allen; Smith, William L.; Schluessel, Peter; Mango, Stephen; SaintGermain, Karen

    2008-01-01

    Since modern ultra-spectral remote sensors have thousands of channels, it is difficult to include all of them in a 1D-var retrieval system. We will describe a physical inversion algorithm, which includes all available channels for the atmospheric temperature, moisture, cloud, and surface parameter retrievals. Both the forward model and the inversion algorithm compress the channel radiances into super channels. These super channels are obtained by projecting the radiance spectra onto a set of pre-calculated eigenvectors. The forward model provides both super channel properties and jacobian in EOF space directly. For ultra-spectral sensors such as Infrared Atmospheric Sounding Interferometer (IASI) and the NPOESS Airborne Sounder Testbed Interferometer (NAST), a compression ratio of more than 80 can be achieved, leading to a significant reduction in computations involved in an inversion process. Results will be shown applying the algorithm to real IASI and NAST data.

  2. Structural resistance of chemically modified 1-D nanostructured titanates in inorganic acid environment

    SciTech Connect

    Marinkovic, Bojan A.; Fredholm, Yann C.; Morgado, Edisson

    2010-10-15

    Sodium containing one-dimensional nanostructured layered titanates (1-D NSLT) were produced both from commercial anatase powder and Brazilian natural rutile mineral sands by alkali hydrothermal process. The 1-D NSLT were chemically modified with proton, cobalt or iron via ionic exchange and all products were additionally submitted to intensive inorganic acid aging (pH = 0.5) for 28 days. The morphology and crystal structure transformations of chemically modified 1-D NSLT were followed by transmission electron microscopy, powder X-ray diffraction, selected area electron diffraction and energy dispersive spectroscopy. It was found that the original sodium rich 1-D NSLT and cobalt substituted 1-D NSLT were completely converted to rutile nanoparticles, while the protonated form was transformed in a 70%-30% (by weight) anatase-rutile nanoparticles mixture, very similar to that of the well-known TiO{sub 2}-photocatalyst P25 (Degussa). The iron substituted 1-D NSLT presented better acid resistance as 13% of the original structure and morphology remained, the rest being converted in rutile. A significant amount of remaining 1-D NSLT was also observed after the acid treatment of the product obtained from rutile sand. The results showed that phase transformation of NSLT into titanium dioxide polymorph in inorganic acid conditions were controllable by varying the exchanged cations. Finally, the possibility to transform, through acid aging, 1-D NSLT obtained from Brazilian natural rutile sand into TiO{sub 2}-polymorphs was demonstrated for the first time to the best of authors' knowledge, opening path for producing TiO{sub 2}-nanoproducts with different morphologies through a simple process and from a low cost precursor.

  3. 1D-1D Coulomb drag in a 6 Million Mobility Bi-layer Heterostructure

    NASA Astrophysics Data System (ADS)

    Bilodeau, Simon; Laroche, Dominique; Xia, Jian-Sheng; Lilly, Mike; Reno, John; Pfeiffer, Loren; West, Ken; Gervais, Guillaume

    We report Coulomb drag measurements in vertically-coupled quantum wires. The wires are fabricated in GaAs/AlGaAs bilayer heterostructures grown from two different MBE chambers: one at Sandia National Laboratories (1.2M mobility), and the other at Princeton University (6M mobility). The previously observed positive and negative drag signals are seen in both types of devices, demonstrating the robustness of the result. However, attempts to determine the temperature dependence of the drag signal in the 1D regime proved challenging in the higher mobility heterostructure (Princeton), in part because of difficulties in aligning the wires within the same transverse subband configuration. Nevertheless, this work, performed at the Microkelvin laboratory of the University of Florida, is an important proof-of-concept for future investigations of the temperature dependence of the 1D-1D drag signal down to a few mK. Such an experiment could confirm the Luttinger charge density wave interlocking predicted to occur in the wires. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under Contract DE-AC04-94AL8500.

  4. Fabrication and characterization of hexagonally patterned quasi-1D ZnO nanowire arrays

    PubMed Central

    2014-01-01

    Quasi-one-dimensional (quasi-1D) ZnO nanowire arrays with hexagonal pattern have been successfully synthesized via the vapor transport process without any metal catalyst. By utilizing polystyrene microsphere self-assembled monolayer, sol–gel-derived ZnO thin films were used as the periodic nucleation sites for the growth of ZnO nanowires. High-quality quasi-1D ZnO nanowires were grown from nucleation sites, and the original hexagonal periodicity is well-preserved. According to the experimental results, the vapor transport solid condensation mechanism was proposed, in which the sol–gel-derived ZnO film acting as a seed layer for nucleation. This simple method provides a favorable way to form quasi-1D ZnO nanostructures applicable to diverse fields such as two-dimensional photonic crystal, nanolaser, sensor arrays, and other optoelectronic devices. PMID:24521308

  5. Fabrication and characterization of hexagonally patterned quasi-1D ZnO nanowire arrays

    NASA Astrophysics Data System (ADS)

    Kuo, Shou-Yi; Lin, Hsin-I.

    2014-02-01

    Quasi-one-dimensional (quasi-1D) ZnO nanowire arrays with hexagonal pattern have been successfully synthesized via the vapor transport process without any metal catalyst. By utilizing polystyrene microsphere self-assembled monolayer, sol-gel-derived ZnO thin films were used as the periodic nucleation sites for the growth of ZnO nanowires. High-quality quasi-1D ZnO nanowires were grown from nucleation sites, and the original hexagonal periodicity is well-preserved. According to the experimental results, the vapor transport solid condensation mechanism was proposed, in which the sol-gel-derived ZnO film acting as a seed layer for nucleation. This simple method provides a favorable way to form quasi-1D ZnO nanostructures applicable to diverse fields such as two-dimensional photonic crystal, nanolaser, sensor arrays, and other optoelectronic devices.

  6. Fabrication and characterization of hexagonally patterned quasi-1D ZnO nanowire arrays.

    PubMed

    Kuo, Shou-Yi; Lin, Hsin-I

    2014-01-01

    Quasi-one-dimensional (quasi-1D) ZnO nanowire arrays with hexagonal pattern have been successfully synthesized via the vapor transport process without any metal catalyst. By utilizing polystyrene microsphere self-assembled monolayer, sol-gel-derived ZnO thin films were used as the periodic nucleation sites for the growth of ZnO nanowires. High-quality quasi-1D ZnO nanowires were grown from nucleation sites, and the original hexagonal periodicity is well-preserved. According to the experimental results, the vapor transport solid condensation mechanism was proposed, in which the sol-gel-derived ZnO film acting as a seed layer for nucleation. This simple method provides a favorable way to form quasi-1D ZnO nanostructures applicable to diverse fields such as two-dimensional photonic crystal, nanolaser, sensor arrays, and other optoelectronic devices. PMID:24521308

  7. The structure and electronic properties of copper iodide 1D nanocrystals within single walled carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Kiselev, N. A.; Kumskov, A. S.; Zhigalina, V. G.; Verbitskiy, N. I.; Yashina, L. V.; Chuvilin, A. L.; Vasiliev, A. L.; Eliseev, A. A.

    2013-11-01

    Copper iodide one-dimensional nanocrystals within single walled carbon nanotubes (1D CuI@SWCNTs), i.e. meta-nanotubes [1], were investigated by high resolution electron microscopy (HRTEM). In meta-nanotubes of diameter Dm = 1.3-1.4 nm produced by arc-discharge (AD) method close-packed hexagonal or deformed cubic 1D crystal anion sublattices were observed with cations in octahedral or tetrahedral positions. These two sublattices reversibly transform to one another. In catalysed chemical vapour deposition (CCVD) meta-nanotubes of diameters Dm = 1.5-2.0 nm cubic anion sublattices are formed. For diameters >=2.0 nm three-dimensional (3D) crystallization is observed.

  8. Design, Synthesis, and Functional Activity of Labeled CD1d Glycolipid Agonists

    PubMed Central

    2013-01-01

    Invariant natural killer T cells (iNKT cells) are restricted by CD1d molecules and activated upon CD1d-mediated presentation of glycolipids to T cell receptors (TCRs) located on the surface of the cell. Because the cytokine response profile is governed by the structure of the glycolipid, we sought a method for labeling various glycolipids to study their in vivo behavior. The prototypical CD1d agonist, α-galactosyl ceramide (α-GalCer) 1, instigates a powerful immune response and the generation of a wide range of cytokines when it is presented to iNKT cell TCRs by CD1d molecules. Analysis of crystal structures of the TCR−α-GalCer–CD1d ternary complex identified the α-methylene unit in the fatty acid side chain, and more specifically the pro-S hydrogen at this position, as a site for incorporating a label. We postulated that modifying the glycolipid in this way would exert a minimal impact on the TCR–glycolipid–CD1d ternary complex, allowing the labeled molecule to function as a good mimic for the CD1d agonist under investigation. To test this hypothesis, the synthesis of a biotinylated version of the CD1d agonist threitol ceramide (ThrCer) was targeted. Both diastereoisomers, epimeric at the label tethering site, were prepared, and functional experiments confirmed the importance of substituting the pro-S, and not the pro-R, hydrogen with the label for optimal activity. Significantly, functional experiments revealed that biotinylated ThrCer (S)-10 displayed behavior comparable to that of ThrCer 5 itself and also confirmed that the biotin residue is available for streptavidin and antibiotin antibody recognition. A second CD1d agonist, namely α-GalCer C20:2 4, was modified in a similar way, this time with a fluorescent label. The labeled α-GalCer C20:2 analogue (11) again displayed functional behavior comparable to that of its unlabeled substrate, supporting the notion that the α-methylene unit in the fatty acid amide chain should be a suitable site for

  9. 1D-TlInSe2: Band Structure, Dielectric Function and Nanorods

    NASA Astrophysics Data System (ADS)

    Mamedov, Nazim; Wakita, Kazuki; Akita, Seiji; Nakayama, Yoshikazu

    2005-01-01

    Linear combination of atomic orbitals (LCAO) analysis of the electronic band states has been completed for one-dimensional (1D) TlInSe2 having rod-like ground state shape of bulky crystal. The total scenario of the occurrence of the band states from the atomic states has been established. According to this scenario, in dipole approximation the optical transitions at band gap (point T of Brillouin zone) are either entirely forbidden or allowed for T2-T10 transitions in e\\perpc configuration provided that either initial or terminate state has T2 symmetry and both are Se-like. As a whole, the obtained results on the electronic spectrum, including dielectric function, are applicable to all obtained 1D-TlInSe2 nanorods which were as thin as 30--50 nm in cross-section, and apparently preserved tetragonal crystal structure of bulky material. The thermal instabilities developing already in bulky samples of 1D-TlInSe2 are considered to be an ultimate source of the nanoparticles emerging in plenty during nanorods preparation. The nanoplates of a chemically similar but 2D material, TlInS2, are demonstrated for comparison to show the absence of nanoparticles in that case. A possibility of nanoparticle preparation using laser excited coherent phonon trains in the nanorods of 1D-TlInSe2 is figured out.

  10. Human serotonin 1D receptor is encoded by a subfamily of two distinct genes: 5-HT1D alpha and 5-HT1D beta.

    PubMed Central

    Weinshank, R L; Zgombick, J M; Macchi, M J; Branchek, T A; Hartig, P R

    1992-01-01

    The serotonin 1D (5-HT1D) receptor is a pharmacologically defined binding site and functional receptor site. Observed variations in the properties of 5-HT1D receptors in different tissues have led to the speculation that multiple receptor proteins with slightly different properties may exist. We report here the cloning, deduced amino acid sequences, pharmacological properties, and second-messenger coupling of a pair of human 5-HT1D receptor genes, which we have designated 5-HT1D alpha and 5-HT1D beta due to their strong similarities in sequence, pharmacological properties, and second-messenger coupling. Both genes are free of introns in their coding regions, are expressed in the human cerebral cortex, and can couple to inhibition of adenylate cyclase activity. The pharmacological binding properties of these two human receptors are very similar, and match closely the pharmacological properties of human, bovine, and guinea pig 5-HT1D sites. Both receptors exhibit high-affinity binding of sumatriptan, a new anti-migraine medication, and thus are candidates for the pharmacological site of action of this drug. Images PMID:1565658

  11. Magneto-optical effects for detection of in-plane magnetization in plasmonic crystals

    NASA Astrophysics Data System (ADS)

    Kalish, A. N.; Belotelov, V. I.

    2016-08-01

    Methods for magneto-optical detection of the in-plane magnetization in a magnetic film due to the deposition of a one-dimensional metallic diffraction grating on the film have been considered. This structure is a magnetoplasmonic crystal, in which the excitation of the waveguide and plasmon modes leads to the appearance of five resonant magneto-optical effects that consist in a change of the intensity, the polarization, and the phase of the transmitted and reflected waves. The conditions responsible for the origin of these effects and their magnitude are determined by the configuration of the incident light, the parameters of the metallic grating, and the chemical composition of the magnetic layer. It has been found that the magnetophotonic intensity effects are the most optimal for the detection of the in-plane magnetization. The influence of the parameters of the metallic grating on the magneto-optical effects has been analyzed and the most optimal conditions for the observation of these effects have been determined. It has also been found that an increase in the concentration of bismuth in a magnetic dielectric material can lead to a weakening of the optical and magneto-optical responses.

  12. Mathematical modeling of 1D binary photonic tuner and realization of temperature sensor

    NASA Astrophysics Data System (ADS)

    Lahiri, A.; Chakraborty, M.

    2011-10-01

    In recent years photonic crystals have become a favored area of research due to their diversified applications. In this paper we propose a mathematical model for analyzing the photonic band gap of a 1D binary photonic crystal (GaAs and air) which allows us to use it effectively as a photonic tuner which is an integral part of any optical amplifier. As optical parameters like reflection and refraction follows similar pattern from each plane within a photonic crystal, we can take help of characteristic matrix for a single plane and multiply (m) times where the crystal consists of (m) periods. Using the fact that the characteristic matrix comes out to be unimodular and taking help of Cayley-Hamilton theorem and Chebyshev polynomials, we expand the matrix of the entire system to derive the location and width of photonic band gaps. Higher stop bands occur at lower frequency of incoming radiation and central bandgap wavelength decreases with increasing angle of incidence. The power transmitted by the tuning crystal decreases for radiations away from normal. Using a polarizer model, the attenuation is computed to be proportional to log|Cos2θ|, where θ is the angle of incidence. The mathematical modeling developed can also be extended for realization of n-array photonic crystal. We have also considered the refractive index modulation with respect to temperature for using it as a temperature sensor.

  13. Brady 1D seismic velocity model ambient noise prelim

    DOE Data Explorer

    Mellors, Robert J.

    2013-10-25

    Preliminary 1D seismic velocity model derived from ambient noise correlation. 28 Green's functions filtered between 4-10 Hz for Vp, Vs, and Qs were calculated. 1D model estimated for each path. The final model is a median of the individual models. Resolution is best for the top 1 km. Poorly constrained with increasing depth.

  14. Structure and binding kinetics of three different human CD1d-alpha-galactosylceramide-specific T cell receptors.

    PubMed

    Gadola, Stephan D; Koch, Michael; Marles-Wright, Jon; Lissin, Nikolai M; Shepherd, Dawn; Matulis, Gediminas; Harlos, Karl; Villiger, Peter M; Stuart, David I; Jakobsen, Bent K; Cerundolo, Vincenzo; Jones, E Yvonne

    2006-03-20

    Invariant human TCR Valpha24-Jalpha18+/Vbeta11+ NKT cells (iNKT) are restricted by CD1d-alpha-glycosylceramides. We analyzed crystal structures and binding characteristics for an iNKT TCR plus two CD1d-alpha-GalCer-specific Vbeta11+ TCRs that use different TCR Valpha chains. The results were similar to those previously reported for MHC-peptide-specific TCRs, illustrating the versatility of the TCR platform. Docking TCR and CD1d-alpha-GalCer structures provided plausible insights into their interaction. The model supports a diagonal orientation of TCR on CD1d and suggests that complementarity determining region (CDR)3alpha, CDR3beta, and CDR1beta interact with ligands presented by CD1d, whereas CDR2beta binds to the CD1d alpha1 helix. This docking provides an explanation for the dominant usage of Vbeta11 and Vbeta8.2 chains by human and mouse iNKT cells, respectively, for recognition of CD1d-alpha-GalCer.

  15. Endoplasmic Reticulum Glycoprotein Quality Control Regulates CD1d Assembly and CD1d-mediated Antigen Presentation*

    PubMed Central

    Kunte, Amit; Zhang, Wei; Paduraru, Crina; Veerapen, Natacha; Cox, Liam R.; Besra, Gurdyal S.; Cresswell, Peter

    2013-01-01

    The non-classical major histocompatibility complex (MHC) homologue CD1d presents lipid antigens to innate-like lymphocytes called natural-killer T (NKT) cells. These cells, by virtue of their broad cytokine repertoire, shape innate and adaptive immune responses. Here, we have assessed the role of endoplasmic reticulum glycoprotein quality control in CD1d assembly and function, specifically the role of a key component of the quality control machinery, the enzyme UDP glucose glycoprotein glucosyltransferase (UGT1). We observe that in UGT1-deficient cells, CD1d associates prematurely with β2-microglobulin (β2m) and is able to rapidly exit the endoplasmic reticulum. At least some of these CD1d-β2m heterodimers are shorter-lived and can be rescued by provision of a defined exogenous antigen, α-galactosylceramide. Importantly, we show that in UGT1-deficient cells the CD1d-β2m heterodimers have altered antigenicity despite the fact that their cell surface levels are unchanged. We propose that UGT1 serves as a quality control checkpoint during CD1d assembly and further suggest that UGT1-mediated quality control can shape the lipid repertoire of newly synthesized CD1d. The quality control process may play a role in ensuring stability of exported CD1d-β2m complexes, in facilitating presentation of low abundance high affinity antigens, or in preventing deleterious responses to self lipids. PMID:23615906

  16. Interaction of environmental contaminants with zebrafish organic anion transporting polypeptide, Oatp1d1 (Slco1d1)

    SciTech Connect

    Popovic, Marta; Zaja, Roko; Fent, Karl; Smital, Tvrtko

    2014-10-01

    Polyspecific transporters from the organic anion transporting polypeptide (OATP/Oatp) superfamily mediate the uptake of a wide range of compounds. In zebrafish, Oatp1d1 transports conjugated steroid hormones and cortisol. It is predominantly expressed in the liver, brain and testes. In this study we have characterized the transport of xenobiotics by the zebrafish Oatp1d1 transporter. We developed a novel assay for assessing Oatp1d1 interactors using the fluorescent probe Lucifer yellow and transient transfection in HEK293 cells. Our data showed that numerous environmental contaminants interact with zebrafish Oatp1d1. Oatp1d1 mediated the transport of diclofenac with very high affinity, followed by high affinity towards perfluorooctanesulfonic acid (PFOS), nonylphenol, gemfibrozil and 17α-ethinylestradiol; moderate affinity towards carbaryl, diazinon and caffeine; and low affinity towards metolachlor. Importantly, many environmental chemicals acted as strong inhibitors of Oatp1d1. A strong inhibition of Oatp1d1 transport activity was found by perfluorooctanoic acid (PFOA), chlorpyrifos-methyl, estrone (E1) and 17β-estradiol (E2), followed by moderate to low inhibition by diethyl phthalate, bisphenol A, 7-acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4 tetrahydronapthalene and clofibrate. In this study we identified Oatp1d1 as a first Solute Carrier (SLC) transporter involved in the transport of a wide range of xenobiotics in fish. Considering that Oatps in zebrafish have not been characterized before, our work on zebrafish Oatp1d1 offers important new insights on the understanding of uptake processes of environmental contaminants, and contributes to the better characterization of zebrafish as a model species. - Highlights: • We optimized a novel assay for determination of Oatp1d1 interactors • Oatp1d1 is the first SLC characterized fish xenobiotic transporter • PFOS, nonylphenol, diclofenac, EE2, caffeine are high affinity Oatp1d1substrates • PFOA, chlorpyrifos

  17. Hyperbranched quasi-1D TiO2 nanostructure for hybrid organic-inorganic solar cells.

    PubMed

    Ghadirzadeh, Ali; Passoni, Luca; Grancini, Giulia; Terraneo, Giancarlo; Li Bassi, Andrea; Petrozza, Annamaria; Di Fonzo, Fabio

    2015-04-15

    The performance of hybrid solar cells is strongly affected by the device morphology. In this work, we demonstrate a poly(3-hexylthiophene-2,5-diyl)/TiO2 hybrid solar cell where the TiO2 photoanode comprises an array of tree-like hyperbranched quasi-1D nanostructures self-assembled from the gas phase. This advanced architecture enables us to increase the power conversion efficiency to over 1%, doubling the efficiency with respect to state of the art devices employing standard mesoporous titania photoanodes. This improvement is attributed to several peculiar features of this array of nanostructures: high interfacial area; increased optical density thanks to the enhanced light scattering; and enhanced crystallization of poly(3-hexylthiophene-2,5-diyl) inside the quasi-1D nanostructure. PMID:25822757

  18. D1/D5 dopamine receptors modulate spatial memory formation.

    PubMed

    da Silva, Weber C N; Köhler, Cristiano C; Radiske, Andressa; Cammarota, Martín

    2012-02-01

    We investigated the effect of the intra-CA1 administration of the D1/D5 receptor antagonist SCH23390 and the D1/D5 receptor agonist SKF38393 on spatial memory in the water maze. When given immediately, but not 3h after training, SCH23390 hindered long-term spatial memory formation without affecting non-spatial memory or the normal functionality of the hippocampus. On the contrary, post-training infusion of SKF38393 enhanced retention and facilitated the spontaneous recovery of the original spatial preference after reversal learning. Our findings demonstrate that hippocampal D1/D5 receptors play an essential role in spatial memory processing.

  19. A human serotonin 1D receptor variant (5HT1D beta) encoded by an intronless gene on chromosome 6.

    PubMed Central

    Demchyshyn, L; Sunahara, R K; Miller, K; Teitler, M; Hoffman, B J; Kennedy, J L; Seeman, P; Van Tol, H H; Niznik, H B

    1992-01-01

    An intronless gene encoding a serotonin receptor (5HT1D beta) has been cloned and functionally expressed in mammalian fibroblast cultures. Based on the deduced amino acid sequence, the gene encodes a 390-amino acid protein displaying considerable homology, within putative transmembrane domains (approximately 75% identity) to the canine and human 5HT1D receptors. Membranes prepared from CHO cells stably expressing the receptor bound [3H]serotonin with high affinity (Kd 4 nM) and displayed a pharmacological profile consistent, but not identical, with that of the characterized serotonin 5HT1D receptor. Most notably, metergoline and serotonergic piperazine derivatives, as a group, display 3- to 8-fold lower affinity for the 5HT1D beta receptor than for the 5HT1D receptor, whereas both receptors display similar affinities for tryptamine derivatives, including the antimigraine drug sumatriptan. Northern blot analysis revealed an mRNA of approximately 5.5 kilobases expressed in human and monkey frontal cortex, medulla, striatum, hippocampus and amygdala but not in cerebellum, olfactory tubercle, and pituitary. The 5HT1D beta gene maps to human chromosome 6. The existence of multiple neuronal 5HT1D-like receptors may help account for some of the complexities associated with [3H]serotonin binding patterns in native membranes. Images PMID:1351684

  20. 60. BOILER CHAMBER No. 1, D LOOP STEAM GENERATOR AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    60. BOILER CHAMBER No. 1, D LOOP STEAM GENERATOR AND MAIN COOLANT PUMP LOOKING NORTHEAST (LOCATION OOO) - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

  1. Severe Hypertriglyceridemia in Glut1D on Ketogenic Diet.

    PubMed

    Klepper, Joerg; Leiendecker, Baerbel; Heussinger, Nicole; Lausch, Ekkehart; Bosch, Friedrich

    2016-04-01

    High-fat ketogenic diets are the only treatment available for Glut1 deficiency (Glut1D). Here, we describe an 8-year-old girl with classical Glut1D responsive to a 3:1 ketogenic diet and ethosuximide. After 3 years on the diet a gradual increase of blood lipids was followed by rapid, severe asymptomatic hypertriglyceridemia (1,910 mg/dL). Serum lipid apheresis was required to determine liver, renal, and pancreatic function. A combination of medium chain triglyceride-oil and a reduction of the ketogenic diet to 1:1 ratio normalized triglyceride levels within days but triggered severe myoclonic seizures requiring comedication with sultiam. Severe hypertriglyceridemia in children with Glut1D on ketogenic diets may be underdiagnosed and harmful. In contrast to congenital hypertriglyceridemias, children with Glut1D may be treated effectively by dietary adjustments alone. PMID:26902182

  2. 1D Nanostructures: Controlled Fabrication and Energy Applications

    SciTech Connect

    Hu, Michael Z.

    2013-01-01

    Jian Wei, Xuchun Song, Chunli Yang, and Michael Z. Hu, 1D Nanostructures: Controlled Fabrication and Energy Applications, Journal of Nanomaterials, published special issue (http://www.hindawi.com/journals/jnm/si/197254/) (2013).

  3. Monochromatic Neutron Tomography Using 1-D PSD Detector at Low Flux Research Reactor

    SciTech Connect

    Ashari, N. Abidin; Saleh, J. Mohamad; Abdullah, M. Zaid; Mohamed, A. Aziz; Azman, A.; Jamro, R.

    2008-03-17

    This paper describes the monochromatic neutron tomography experiment using the 1-D Position Sensitive Neutron Detector (PSD) located at Nuclear Malaysia TRIGA MARK II Research reactor. Experimental work was performed using monochromatic neutron source from beryllium filter and HOPG crystal monochromator. The principal main aim of this experiment was to test the detector efficiency, image reconstruction algorithm and the usage of 0.5 nm monochromatic neutrons for the neutron tomography setup. Other objective includes gathering important parameters and features to characterize the system.

  4. Monochromatic Neutron Tomography Using 1-D PSD Detector at Low Flux Research Reactor

    NASA Astrophysics Data System (ADS)

    Ashari, N. Abidin; Saleh, J. Mohamad; Abdullah, M. Zaid; Mohamed, A. Aziz; Azman, A.; Jamro, R.

    2008-03-01

    This paper describes the monochromatic neutron tomography experiment using the 1-D Position Sensitive Neutron Detector (PSD) located at Nuclear Malaysia TRIGA MARK II Research reactor. Experimental work was performed using monochromatic neutron source from beryllium filter and HOPG crystal monochromator. The principal main aim of this experiment was to test the detector efficiency, image reconstruction algorithm and the usage of 0.5 nm monochromatic neutrons for the neutron tomography setup. Other objective includes gathering important parameters and features to characterize the system.

  5. TBC1D24 genotype–phenotype correlation

    PubMed Central

    Balestrini, Simona; Milh, Mathieu; Castiglioni, Claudia; Lüthy, Kevin; Finelli, Mattea J.; Verstreken, Patrik; Cardon, Aaron; Stražišar, Barbara Gnidovec; Holder, J. Lloyd; Lesca, Gaetan; Mancardi, Maria M.; Poulat, Anne L.; Repetto, Gabriela M.; Banka, Siddharth; Bilo, Leonilda; Birkeland, Laura E.; Bosch, Friedrich; Brockmann, Knut; Cross, J. Helen; Doummar, Diane; Félix, Temis M.; Giuliano, Fabienne; Hori, Mutsuki; Hüning, Irina; Kayserili, Hulia; Kini, Usha; Lees, Melissa M.; Meenakshi, Girish; Mewasingh, Leena; Pagnamenta, Alistair T.; Peluso, Silvio; Mey, Antje; Rice, Gregory M.; Rosenfeld, Jill A.; Taylor, Jenny C.; Troester, Matthew M.; Stanley, Christine M.; Ville, Dorothee; Walkiewicz, Magdalena; Falace, Antonio; Fassio, Anna; Lemke, Johannes R.; Biskup, Saskia; Tardif, Jessica; Ajeawung, Norbert F.; Tolun, Aslihan; Corbett, Mark; Gecz, Jozef; Afawi, Zaid; Howell, Katherine B.; Oliver, Karen L.; Berkovic, Samuel F.; Scheffer, Ingrid E.; de Falco, Fabrizio A.; Oliver, Peter L.; Striano, Pasquale; Zara, Federico

    2016-01-01

    Objective: To evaluate the phenotypic spectrum associated with mutations in TBC1D24. Methods: We acquired new clinical, EEG, and neuroimaging data of 11 previously unreported and 37 published patients. TBC1D24 mutations, identified through various sequencing methods, can be found online (http://lovd.nl/TBC1D24). Results: Forty-eight patients were included (28 men, 20 women, average age 21 years) from 30 independent families. Eighteen patients (38%) had myoclonic epilepsies. The other patients carried diagnoses of focal (25%), multifocal (2%), generalized (4%), and unclassified epilepsy (6%), and early-onset epileptic encephalopathy (25%). Most patients had drug-resistant epilepsy. We detail EEG, neuroimaging, developmental, and cognitive features, treatment responsiveness, and physical examination. In silico evaluation revealed 7 different highly conserved motifs, with the most common pathogenic mutation located in the first. Neuronal outgrowth assays showed that some TBC1D24 mutations, associated with the most severe TBC1D24-associated disorders, are not necessarily the most disruptive to this gene function. Conclusions: TBC1D24-related epilepsy syndromes show marked phenotypic pleiotropy, with multisystem involvement and severity spectrum ranging from isolated deafness (not studied here), benign myoclonic epilepsy restricted to childhood with complete seizure control and normal intellect, to early-onset epileptic encephalopathy with severe developmental delay and early death. There is no distinct correlation with mutation type or location yet, but patterns are emerging. Given the phenotypic breadth observed, TBC1D24 mutation screening is indicated in a wide variety of epilepsies. A TBC1D24 consortium was formed to develop further research on this gene and its associated phenotypes. PMID:27281533

  6. Polychalcogenophosphate flux synthesis of 1D-KInP 2Se 6 and 1D and 3D-NaCrP 2S 6

    NASA Astrophysics Data System (ADS)

    Coste, Servane; Kopnin, Evgeni; Evain, Michel; Jobic, Stéphane; Brec, Raymond; Chondroudis, Konstantinos; Kanatzidis, Mercouri G.

    2002-04-01

    Three new chalcogenophosphates, 1D-KInP 2Se 6 ( I), 1D-NaCrP 2S 6 ( II) and 3D-NaCrP 2S 6 ( III), have been synthesized and their structure determined from single crystal diffraction analysis. ( I) and ( II) crystallize in the monoclinic system (space group P2 1/n, No. 14) with cell parameters a=7.5112(11), b=6.4861(5), c=22.789(2) Å and β=98.912(16)° ( V=1096.9(2) Å 3), Z=4 and R/ Rw( F2)=0.0234/0.0387 (for 900 observed reflections and 92 refined parameters) for ( I) and a=7.0279(5), b=5.8797(2), c=21.2578(14) Å and β=92.110(3)° ( V=877.82(9) Å 3), Z=4 and R/ Rw( F2)=0.0572/0.1151 (for 1455 observed reflections and 92 refined parameters) for ( II). Both materials exhibit 1/ ∞[MP 2Q 6] - chains built upon [MQ 6] octahedra (M=In, Cr; Q=Se, S) sharing edges to define 1/ ∞[MQ 4] 5- zigzag fibers which are capped by tetradentate ethane-like [P 2Q 6] groups. ( III) crystallizes in the orthorhombic system (space group Fdd2, No. 43) with cell parameters a=10.9742(7), b=7.9828(6), c=20.8590(19) Å ( V=1827.3(4) Å 3), Z=8 and R/ Rw=0.0184/0.0378 (for 967 observed reflections and 47 refined parameters), and displays a three-dimensional framework arrangement. Its structure is similar to that of TiP 2S 6 where titanium atoms are substituted for the chromium, the sodium atoms being inserted in the empty tunnels to ensure the charge balance. The exfoliation properties of 1D-NaCrP 2S 6 in polar solvents are reported.

  7. Realizing 1-D conducting channel between oppositely gated regions in bilayer graphene

    NASA Astrophysics Data System (ADS)

    Lee, Janghee; Watanabe, Kenji; Taniguchi, Takashi; Lee, Hu-Jong

    The band gap of bilayer graphene (BLG) can be tuned by applying an external electric field perpendicular to the plane of a BLG sheet. If direction of the electric fields in two adjacent regions in BLG are opposite, one-dimensional (1-D) conducting channel emerges at the boundary between two regions with chiral nature. In this presentation, we introduce a method for fabricating two pairs of split-gates attached to BLG, which is sandwiched between two atomically clean hexagonal boron nitride (h-BN) single crystals and thus allows ballistic transport of carriers at least within the device size. Current-voltage characteristics show a large transport gap, which is comparable to the results obtained from optical measurements and numerical calculations. Opening the band gap in two adjacent regions of the BLG flake by oppositely gated electric fields, we observed metallic behavior in transport characteristics along the boundary between the two regions although the resistance of two gapped regions are a few hundreds of k Ω. These results indicate that a 1-D conducting channel formed between the two regions where the induced band gaps were inverted to each other. The formation of this 1-D conducting channel mimics the topological edge conducting channels emerging at the boundary of a two-dimensional topological insulator and may be utilized for applying BLG to valleytronics

  8. 1D nanocrystals with precisely controlled dimensions, compositions, and architectures

    NASA Astrophysics Data System (ADS)

    Pang, Xinchang; He, Yanjie; Jung, Jaehan; Lin, Zhiqun

    2016-09-01

    The ability to synthesize a diverse spectrum of one-dimensional (1D) nanocrystals presents an enticing prospect for exploring nanoscale size- and shape-dependent properties. Here we report a general strategy to craft a variety of plain nanorods, core-shell nanorods, and nanotubes with precisely controlled dimensions and compositions by capitalizing on functional bottlebrush-like block copolymers with well-defined structures and narrow molecular weight distributions as nanoreactors. These cylindrical unimolecular nanoreactors enable a high degree of control over the size, shape, architecture, surface chemistry, and properties of 1D nanocrystals. We demonstrate the synthesis of metallic, ferroelectric, upconversion, semiconducting, and thermoelectric 1D nanocrystals, among others, as well as combinations thereof.

  9. The GIRAFFE Archive: 1D and 3D Spectra

    NASA Astrophysics Data System (ADS)

    Royer, F.; Jégouzo, I.; Tajahmady, F.; Normand, J.; Chilingarian, I.

    2013-10-01

    The GIRAFFE Archive (http://giraffe-archive.obspm.fr) contains the reduced spectra observed with the intermediate and high resolution multi-fiber spectrograph installed at VLT/UT2 (ESO). In its multi-object configuration and the different integral field unit configurations, GIRAFFE produces 1D spectra and 3D spectra. We present here the status of the archive and the different functionalities to select and download both 1D and 3D data products, as well as the present content. The two collections are available in the VO: the 1D spectra (summed in the case of integral field observations) and the 3D field observations. These latter products can be explored using the VO Paris Euro3D Client (http://voplus.obspm.fr/ chil/Euro3D).

  10. PC-1D installation manual and user's guide

    SciTech Connect

    Basore, P.A.

    1991-05-01

    PC-1D is a software package for personal computers that uses finite-element analysis to solve the fully-coupled two-carrier semiconductor transport equations in one dimension. This program is particularly useful for analyzing the performance of optoelectronic devices such as solar cells, but can be applied to any bipolar device whose carrier flows are primarily one-dimensional. This User's Guide provides the information necessary to install PC-1D, define a problem for solution, solve the problem, and examine the results. Example problems are presented which illustrate these steps. The physical models and numerical methods utilized are presented in detail. This document supports version 3.1 of PC-1D, which incorporates faster numerical algorithms with better convergence properties than previous versions of the program. 51 refs., 17 figs., 5 tabs.

  11. Pitch-based pattern splitting for 1D layout

    NASA Astrophysics Data System (ADS)

    Nakayama, Ryo; Ishii, Hiroyuki; Mikami, Koji; Tsujita, Koichiro; Yaegashi, Hidetami; Oyama, Kenichi; Smayling, Michael C.; Axelrad, Valery

    2015-07-01

    The pattern splitting algorithm for 1D Gridded-Design-Rules layout (1D layout) for sub-10 nm node logic devices is shown. It is performed with integer linear programming (ILP) based on the conflict graph created from a grid map for each designated pitch. The relation between the number of times for patterning and the minimum pitch is shown systematically with a sample pattern of contact layer for each node. From the result, the number of times for patterning for 1D layout is fewer than that for conventional 2D layout. Moreover, an experimental result including SMO and total integrated process with hole repair technique is presented with the sample pattern of contact layer whose pattern density is relatively high among critical layers (fin, gate, local interconnect, contact, and metal).

  12. 1D nanocrystals with precisely controlled dimensions, compositions, and architectures.

    PubMed

    Pang, Xinchang; He, Yanjie; Jung, Jaehan; Lin, Zhiqun

    2016-09-16

    The ability to synthesize a diverse spectrum of one-dimensional (1D) nanocrystals presents an enticing prospect for exploring nanoscale size- and shape-dependent properties. Here we report a general strategy to craft a variety of plain nanorods, core-shell nanorods, and nanotubes with precisely controlled dimensions and compositions by capitalizing on functional bottlebrush-like block copolymers with well-defined structures and narrow molecular weight distributions as nanoreactors. These cylindrical unimolecular nanoreactors enable a high degree of control over the size, shape, architecture, surface chemistry, and properties of 1D nanocrystals. We demonstrate the synthesis of metallic, ferroelectric, upconversion, semiconducting, and thermoelectric 1D nanocrystals, among others, as well as combinations thereof. PMID:27634531

  13. Flexible Photodetectors Based on 1D Inorganic Nanostructures

    PubMed Central

    Lou, Zheng

    2015-01-01

    Flexible photodetectors with excellent flexibility, high mechanical stability and good detectivity, have attracted great research interest in recent years. 1D inorganic nanostructures provide a number of opportunities and capabilities for use in flexible photodetectors as they have unique geometry, good transparency, outstanding mechanical flexibility, and excellent electronic/optoelectronic properties. This article offers a comprehensive review of several types of flexible photodetectors based on 1D nanostructures from the past ten years, including flexible ultraviolet, visible, and infrared photodetectors. High‐performance organic‐inorganic hybrid photodetectors, as well as devices with 1D nanowire (NW) arrays, are also reviewed. Finally, new concepts of flexible photodetectors including piezophototronic, stretchable and self‐powered photodetectors are examined to showcase the future research in this exciting field. PMID:27774404

  14. GIS-BASED 1-D DIFFUSIVE WAVE OVERLAND FLOW MODEL

    SciTech Connect

    KALYANAPU, ALFRED; MCPHERSON, TIMOTHY N.; BURIAN, STEVEN J.

    2007-01-17

    This paper presents a GIS-based 1-d distributed overland flow model and summarizes an application to simulate a flood event. The model estimates infiltration using the Green-Ampt approach and routes excess rainfall using the 1-d diffusive wave approximation. The model was designed to use readily available topographic, soils, and land use/land cover data and rainfall predictions from a meteorological model. An assessment of model performance was performed for a small catchment and a large watershed, both in urban environments. Simulated runoff hydrographs were compared to observations for a selected set of validation events. Results confirmed the model provides reasonable predictions in a short period of time.

  15. Observation of Dynamical Fermionization in 1D Bose Gases

    NASA Astrophysics Data System (ADS)

    Malvania, Neel; Xia, Lin; Xu, Wei; Wilson, Joshua M.; Zundel, Laura A.; Rigol, Marcos; Weiss, David S.

    2016-05-01

    The momentum distribution of a harmonically trapped 1D Bose gases in the Tonks-Girardeau limit is expected to undergo dynamical fermionization. That is, after the harmonic trap is suddenly turned off, the momentum distribution steadily transforms into that of an ideal Fermi gas in the same initial trap. We measure 1D momentum distributions at variable times after such a quench, and observe the predicted dynamical fermionization. In addition to working in the strong coupling limit, we also perform the experiment with intermediate coupling, where theoretical calculations are more challenging.

  16. Structural Basis of the Interaction between Tuberous Sclerosis Complex 1 (TSC1) and Tre2-Bub2-Cdc16 Domain Family Member 7 (TBC1D7).

    PubMed

    Qin, Jiayue; Wang, Zhizhi; Hoogeveen-Westerveld, Marianne; Shen, Guobo; Gong, Weimin; Nellist, Mark; Xu, Wenqing

    2016-04-15

    Mutations in TSC1 or TSC2 cause tuberous sclerosis complex (TSC), an autosomal dominant disorder characterized by the occurrence of benign tumors in various vital organs and tissues. TSC1 and TSC2, the TSC1 and TSC2 gene products, form the TSC protein complex that senses specific cellular growth conditions to control mTORC1 signaling. TBC1D7 is the third subunit of the TSC complex, and helps to stabilize the TSC1-TSC2 complex through its direct interaction with TSC1. Homozygous inactivation of TBC1D7 causes intellectual disability and megaencephaly. Here we report the crystal structure of a TSC1-TBC1D7 complex and biochemical characterization of the TSC1-TBC1D7 interaction. TBC1D7 interacts with the C-terminal region of the predicted coiled-coil domain of TSC1. The TSC1-TBC1D7 interface is largely hydrophobic, involving the α4 helix of TBC1D7. Each TBC1D7 molecule interacts simultaneously with two parallel TSC1 helices from two TSC1 molecules, suggesting that TBC1D7 may stabilize the TSC complex by tethering the C-terminal ends of two TSC1 coiled-coils.

  17. Single molecule magnet behavior observed in a 1-D dysprosium chain with quasi-D5h symmetry.

    PubMed

    Huang, Xing-Cai; Zhang, Ming; Wu, Dayu; Shao, Dong; Zhao, Xin-Hua; Huang, Wei; Wang, Xin-Yi

    2015-12-28

    Two one-dimensional (1-D) chain complexes with pentagonal bipyramidal Dy(III) centers have been synthesized and magnetically characterized. Field-induced single molecule magnet behavior has been revealed in both compounds, which is still rarely reported in a lanthanide compound with a pentagonal bipyramidal coordination geometry. Their crystal field parameters and orientations of the magnetic easy axes were obtained from the simulation of the magnetic data and the electrostatic model calculation. PMID:26593051

  18. Non-cooperative Brownian donkeys: A solvable 1D model

    NASA Astrophysics Data System (ADS)

    Jiménez de Cisneros, B.; Reimann, P.; Parrondo, J. M. R.

    2003-12-01

    A paradigmatic 1D model for Brownian motion in a spatially symmetric, periodic system is tackled analytically. Upon application of an external static force F the system's response is an average current which is positive for F < 0 and negative for F > 0 (absolute negative mobility). Under suitable conditions, the system approaches 100% efficiency when working against the external force F.

  19. 1D design style implications for mask making and CEBL

    NASA Astrophysics Data System (ADS)

    Smayling, Michael C.

    2013-09-01

    At advanced nodes, CMOS logic is being designed in a highly regular design style because of the resolution limitations of optical lithography equipment. Logic and memory layouts using 1D Gridded Design Rules (GDR) have been demonstrated to nodes beyond 12nm.[1-4] Smaller nodes will require the same regular layout style but with multiple patterning for critical layers. One of the significant advantages of 1D GDR is the ease of splitting layouts into lines and cuts. A lines and cuts approach has been used to achieve good pattern fidelity and process margin to below 12nm.[4] Line scaling with excellent line-edge roughness (LER) has been demonstrated with self-aligned spacer processing.[5] This change in design style has important implications for mask making: • The complexity of the masks will be greatly reduced from what would be required for 2D designs with very complex OPC or inverse lithography corrections. • The number of masks will initially increase, as for conventional multiple patterning. But in the case of 1D design, there are future options for mask count reduction. • The line masks will remain simple, with little or no OPC, at pitches (1x) above 80nm. This provides an excellent opportunity for continual improvement of line CD and LER. The line pattern will be processed through a self-aligned pitch division sequence to divide pitch by 2 or by 4. • The cut masks can be done with "simple OPC" as demonstrated to beyond 12nm.[6] Multiple simple cut masks may be required at advanced nodes. "Coloring" has been demonstrated to below 12nm for two colors and to 8nm for three colors. • Cut/hole masks will eventually be replaced by e-beam direct write using complementary e-beam lithography (CEBL).[7-11] This transition is gated by the availability of multiple column e-beam systems with throughput adequate for high- volume manufacturing. A brief description of 1D and 2D design styles will be presented, followed by examples of 1D layouts. Mask complexity for 1

  20. Numerical simulations of heavily polluted fine-grained sediment remobilization using 1D, 1D+, and 2D channel schematization.

    PubMed

    Kaiglová, Jana; Langhammer, Jakub; Jiřinec, Petr; Janský, Bohumír; Chalupová, Dagmar

    2015-03-01

    This article used various hydrodynamic and sediment transport models to analyze the potential and the limits of different channel schematizations. The main aim was to select and evaluate the most suitable simulation method for fine-grained sediment remobilization assessment. Three types of channel schematization were selected to study the flow potential for remobilizing fine-grained sediment in artificially modified channels. Schematization with a 1D cross-sectional horizontal plan, a 1D+ approach, splitting the riverbed into different functional zones, and full 2D mesh, adopted in MIKE by the DHI modeling suite, was applied to the study. For the case study, a 55-km stretch of the Bílina River, in the Czech Republic, Central Europe, which has been heavily polluted by the chemical and coal mining industry since the mid-twentieth century, was selected. Long-term exposure to direct emissions of toxic pollutants including heavy metals and persistent organic pollutants (POPs) resulted in deposits of pollutants in fine-grained sediments in the riverbed. Simulations, based on three hydrodynamic model schematizations, proved that for events not exceeding the extent of the riverbed profile, the 1D schematization can provide comparable results to a 2D model. The 1D+ schematization can improve accuracy while keeping the benefits of high-speed simulation and low requirements of input DEM data, but the method's suitability is limited by the channel properties. PMID:25687259

  1. Bloch oscillations as generators of polarons in a 1D crystal

    NASA Astrophysics Data System (ADS)

    Nazareno, H. N.; Brito, P. E. de

    2016-08-01

    The main purpose of this work is to characterize the kind of propagation/localization of carriers in a one-dimensional crystalline structure along the tight-binding model while the electron-phonon interaction is taken into account through a deformation potential and the system is under the action of a dc electric field. The lattice was treated in the classical formalism of harmonic vibrations. A remarkable effect is obtained due to the presence of the electric field. On one side the particle performs Bloch oscillations and at the same time it interacts with the lattice and as a result at each turning point of its trajectory phonons are generated that carry with them a fraction of the electronic wave packet, it is the polaron formation. This way the Bloch oscillations pump polarons into the system. We explain why the polaron is formed at returning points of the oscillations.

  2. 1D coordination polymers with polychalcogenides as linkers between metal atoms

    SciTech Connect

    Kysliak, Oleksandr; Beck, Johannes

    2013-07-15

    The reactions of zinc metal with elemental selenium and selenium/sulfur mixtures in liquid ammonia or methylamine under solvothermal conditions in closed glass ampoules at 50 °C lead within some days specifically to [Zn(NH{sub 3}){sub 2}Se{sub 4}]{sub n} (1), [Zn(MeNH{sub 2}){sub 2}Se{sub 4}]{sub n} (2), [Zn(NH{sub 3}){sub 2}Se{sub 2.23}S{sub 1.77}]{sub n} (3). From MnCl{sub 2}, Rb{sub 2}Se and excess Se in n-butylamine [Mn({sup n}BuNH{sub 2}){sub 4}Se{sub 6}]{sub n} (4) is obtained after prolonged reaction time at ambient temperature. The compounds are sensitive towards air and loss of NH{sub 3} or the amine ligands. The crystal structures were determined by single crystal diffraction at low temperatures. As a common structural feature, all compounds represent 1D coordination polymers with polychalcogenide chains as linkers between the metal atoms and consist of infinite [M–Ch{sub m}–]{sub n} chains (M=Zn, Mn; Ch{sub m}=Se{sub 4}, (S/Se){sub 4}, Se{sub 6}). The Zn central atoms in 1–3 have tetrahedral coordination with two amine ligands, the Mn atoms in 4 have octahedral coordination with four amine ligands and cis position of the two Se atoms. Raman spectra of 1–3 show the stretching mode vibrations of the Ch{sub 4} groups. The observation of S–S, S–Se, and Se–Se vibration bands in the spectrum of 3 indicates the presence of mixed S/Se polyanions. An optical band gap of 1.86(5) eV was determined for 2 by diffuse reflectance spectroscopy. - Graphical abstract: The reaction of Zn and Se in liquid methylamine yields dark red [Zn(NH{sub 2}CH{sub 3})Se{sub 4}], a 1D coordination polymer consisting of helical Zn–Se{sub 4}–Zn– chains. - Highlights: • A series of 1D coordination polymers consisting of metal amine complexes concatenated by polychalcogenide ions is presented. • Syntheses were performed as solvothermal reactions in liquid ammonia, liquid methylamine and n-butylamine. • Crystal structures are dominated by helices [M–Ch{sub m

  3. 1-D Numerical Analysis of ABCC Engine Performance

    NASA Technical Reports Server (NTRS)

    Holden, Richard

    1999-01-01

    ABCC engine combines air breathing and rocket engine into a single engine to increase the specific impulse over an entire flight trajectory. Except for the heat source, the basic operation of the ABCC is similar to the basic operation of the RBCC engine. The ABCC is intended to have a higher specific impulse than the RBCC for single stage Earth to orbit vehicle. Computational fluid dynamics (CFD) is a useful tool for the analysis of complex transport processes in various components in ABCC propulsion system. The objective of the present research was to develop a transient 1-D numerical model using conservation of mass, linear momentum, and energy equations that could be used to predict flow behavior throughout a generic ABCC engine following a flight path. At specific points during the development of the 1-D numerical model a myriad of tests were performed to prove the program produced consistent, realistic numbers that follow compressible flow theory for various inlet conditions.

  4. Phase diagram of a bulk 1d lattice Coulomb gas

    NASA Astrophysics Data System (ADS)

    Démery, V.; Monsarrat, R.; Dean, D. S.; Podgornik, R.

    2016-01-01

    The exact solution, via transfer matrix, of the simple one-dimensional lattice Coulomb gas (1d LCG) model can reproduce peculiar features of ionic liquid capacitors, such as overscreening, layering, and camel- and bell-shaped capacitance curves. Using the same transfer matrix method, we now compute the bulk properties of the 1d LCG in the constant voltage ensemble. We unveil a phase diagram with rich structure exhibiting low-density disordered and high-density ordered phases, separated by a first-order phase transition at low temperature; the solid state at full packing can be ordered or not, depending on the temperature. This phase diagram, which is strikingly similar to its three-dimensional counterpart, also sheds light on the behaviour of the confined system.

  5. 1D Josephson quantum interference grids: diffraction patterns and dynamics

    NASA Astrophysics Data System (ADS)

    Lucci, M.; Badoni, D.; Corato, V.; Merlo, V.; Ottaviani, I.; Salina, G.; Cirillo, M.; Ustinov, A. V.; Winkler, D.

    2016-02-01

    We investigate the magnetic response of transmission lines with embedded Josephson junctions and thus generating a 1D underdamped array. The measured multi-junction interference patterns are compared with the theoretical predictions for Josephson supercurrent modulations when an external magnetic field couples both to the inter-junction loops and to the junctions themselves. The results provide a striking example of the analogy between Josephson phase modulation and 1D optical diffraction grid. The Fiske resonances in the current-voltage characteristics with voltage spacing {Φ0}≤ft(\\frac{{\\bar{c}}}{2L}\\right) , where L is the total physical length of the array, {Φ0} the magnetic flux quantum and \\bar{c} the speed of light in the transmission line, demonstrate that the discrete line supports stable dynamic patterns generated by the ac Josephson effect interacting with the cavity modes of the line.

  6. Morphodynamics and sediment tracers in 1-D (MAST-1D): 1-D sediment transport that includes exchange with an off-channel sediment reservoir

    NASA Astrophysics Data System (ADS)

    Lauer, J. Wesley; Viparelli, Enrica; Piégay, Hervé

    2016-07-01

    Bed material transported in geomorphically active gravel bed rivers often has a local source at nearby eroding banks and ends up sequestered in bars not far downstream. However, most 1-D numerical models for gravel transport assume that gravel originates from and deposits on the channel bed. In this paper, we present a 1-D framework for simulating morphodynamic evolution of bed elevation and size distribution in a gravel-bed river that actively exchanges sediment with its floodplain, which is represented as an off-channel sediment reservoir. The model is based on the idea that sediment enters the channel at eroding banks whose elevation depends on total floodplain sediment storage and on the average elevation of the floodplain relative to the channel bed. Lateral erosion of these banks occurs at a specified rate that can represent either net channel migration or channel widening. Transfer of material out of the channel depends on a typical bar thickness and a specified lateral exchange rate due either to net channel migration or narrowing. The model is implemented using an object oriented framework that allows users to explore relationships between bank supply, bed structure, and lateral change rates. It is applied to a ∼50-km reach of the Ain River, France, that experienced significant reduction in sediment supply due to dam construction during the 20th century. Results are strongly sensitive to lateral exchange rates, showing that in this reach, the supply of sand and gravel at eroding banks and the sequestration of gravel in point bars can have strong influence on overall reach-scale sediment budgets.

  7. Enhancing Solar Cell Efficiencies through 1-D Nanostructures

    PubMed Central

    2009-01-01

    The current global energy problem can be attributed to insufficient fossil fuel supplies and excessive greenhouse gas emissions resulting from increasing fossil fuel consumption. The huge demand for clean energy potentially can be met by solar-to-electricity conversions. The large-scale use of solar energy is not occurring due to the high cost and inadequate efficiencies of existing solar cells. Nanostructured materials have offered new opportunities to design more efficient solar cells, particularly one-dimensional (1-D) nanomaterials for enhancing solar cell efficiencies. These 1-D nanostructures, including nanotubes, nanowires, and nanorods, offer significant opportunities to improve efficiencies of solar cells by facilitating photon absorption, electron transport, and electron collection; however, tremendous challenges must be conquered before the large-scale commercialization of such cells. This review specifically focuses on the use of 1-D nanostructures for enhancing solar cell efficiencies. Other nanostructured solar cells or solar cells based on bulk materials are not covered in this review. Major topics addressed include dye-sensitized solar cells, quantum-dot-sensitized solar cells, and p-n junction solar cells.

  8. Constructing 3D interaction maps from 1D epigenomes

    PubMed Central

    Zhu, Yun; Chen, Zhao; Zhang, Kai; Wang, Mengchi; Medovoy, David; Whitaker, John W.; Ding, Bo; Li, Nan; Zheng, Lina; Wang, Wei

    2016-01-01

    The human genome is tightly packaged into chromatin whose functional output depends on both one-dimensional (1D) local chromatin states and three-dimensional (3D) genome organization. Currently, chromatin modifications and 3D genome organization are measured by distinct assays. An emerging question is whether it is possible to deduce 3D interactions by integrative analysis of 1D epigenomic data and associate 3D contacts to functionality of the interacting loci. Here we present EpiTensor, an algorithm to identify 3D spatial associations within topologically associating domains (TADs) from 1D maps of histone modifications, chromatin accessibility and RNA-seq. We demonstrate that active promoter–promoter, promoter–enhancer and enhancer–enhancer associations identified by EpiTensor are highly concordant with those detected by Hi-C, ChIA-PET and eQTL analyses at 200 bp resolution. Moreover, EpiTensor has identified a set of interaction hotspots, characterized by higher chromatin and transcriptional activity as well as enriched TF and ncRNA binding across diverse cell types, which may be critical for stabilizing the local 3D interactions. PMID:26960733

  9. Constructing 3D interaction maps from 1D epigenomes.

    PubMed

    Zhu, Yun; Chen, Zhao; Zhang, Kai; Wang, Mengchi; Medovoy, David; Whitaker, John W; Ding, Bo; Li, Nan; Zheng, Lina; Wang, Wei

    2016-01-01

    The human genome is tightly packaged into chromatin whose functional output depends on both one-dimensional (1D) local chromatin states and three-dimensional (3D) genome organization. Currently, chromatin modifications and 3D genome organization are measured by distinct assays. An emerging question is whether it is possible to deduce 3D interactions by integrative analysis of 1D epigenomic data and associate 3D contacts to functionality of the interacting loci. Here we present EpiTensor, an algorithm to identify 3D spatial associations within topologically associating domains (TADs) from 1D maps of histone modifications, chromatin accessibility and RNA-seq. We demonstrate that active promoter-promoter, promoter-enhancer and enhancer-enhancer associations identified by EpiTensor are highly concordant with those detected by Hi-C, ChIA-PET and eQTL analyses at 200 bp resolution. Moreover, EpiTensor has identified a set of interaction hotspots, characterized by higher chromatin and transcriptional activity as well as enriched TF and ncRNA binding across diverse cell types, which may be critical for stabilizing the local 3D interactions. PMID:26960733

  10. Development of 1D Liner Compression Code for IDL

    NASA Astrophysics Data System (ADS)

    Shimazu, Akihisa; Slough, John; Pancotti, Anthony

    2015-11-01

    A 1D liner compression code is developed to model liner implosion dynamics in the Inductively Driven Liner Experiment (IDL) where FRC plasmoid is compressed via inductively-driven metal liners. The driver circuit, magnetic field, joule heating, and liner dynamics calculations are performed at each time step in sequence to couple these effects in the code. To obtain more realistic magnetic field results for a given drive coil geometry, 2D and 3D effects are incorporated into the 1D field calculation through use of correction factor table lookup approach. Commercial low-frequency electromagnetic fields solver, ANSYS Maxwell 3D, is used to solve the magnetic field profile for static liner condition at various liner radius in order to derive correction factors for the 1D field calculation in the code. The liner dynamics results from the code is verified to be in good agreement with the results from commercial explicit dynamics solver, ANSYS Explicit Dynamics, and previous liner experiment. The developed code is used to optimize the capacitor bank and driver coil design for better energy transfer and coupling. FRC gain calculations are also performed using the liner compression data from the code for the conceptual design of the reactor sized system for fusion energy gains.

  11. Molecular characterization of zebrafish Oatp1d1 (Slco1d1), a novel organic anion-transporting polypeptide.

    PubMed

    Popovic, Marta; Zaja, Roko; Fent, Karl; Smital, Tvrtko

    2013-11-22

    The organic anion-transporting polypeptide (OATP/Oatp) superfamily includes a group of polyspecific transporters that mediate transport of large amphipathic, mostly anionic molecules across cell membranes of eukaryotes. OATPs/Oatps are involved in the disposition and elimination of numerous physiological and foreign compounds. However, in non-mammalian species, the functional properties of Oatps remain unknown. We aimed to elucidate the role of Oatp1d1 in zebrafish to gain insights into the functional and structural evolution of the OATP1/Oatp1 superfamily. We show that diversification of the OATP1/Oatp1 family occurs after the emergence of jawed fish and that the OATP1A/Oatp1a and OATP1B/Oatp1b subfamilies appeared at the root of tetrapods. The Oatp1d subfamily emerged in teleosts and is absent in tetrapods. The zebrafish Oatp1d1 is similar to mammalian OATP1A/Oatp1a and OATP1B/Oatp1b members, with the main physiological role in transport and balance of steroid hormones. Oatp1d1 activity is dependent upon pH gradient, which could indicate bicarbonate exchange as a mode of transport. Our analysis of evolutionary conservation and structural properties revealed that (i) His-79 in intracellular loop 3 is conserved within OATP1/Oatp1 family and is crucial for the transport activity; (ii) N-glycosylation impacts membrane targeting and is conserved within the OATP1/Oatp1 family with Asn-122, Asn-133, Asn-499, and Asn-512 residues involved; (iii) the evolutionarily conserved cholesterol recognition interaction amino acid consensus motif is important for membrane localization; and (iv) Oatp1d1 is present in dimeric and possibly oligomeric form in the cell membrane. In conclusion, we describe the first detailed characterization of a new Oatp transporter in zebrafish, offering important insights into the functional evolution of the OATP1/Oatp1 family and the physiological role of Oatp1d1.

  12. Optical reflectance and omnidirectional bandgaps in Fibonacci quasicrystals type 1-D multilayer structures containing exponentially graded material

    NASA Astrophysics Data System (ADS)

    Singh, Bipin K.; Thapa, Khem B.; Pandey, Praveen C.

    2013-06-01

    A theoretical study of optical reflectance and reflection bands of 1-D photonic quasi-crystals (Fibonacci type arrangement) composed of exponentially graded material is presented. The proposed structures consist of two different layers, one of them is of constant refractive index (L) and the other one is of exponentially graded refractive index (S) dielectric materials. Four different generations (2nd, 3rd, 4th and 5th) of the Fibonacci sequence for 10 periods in one dimension (1-D) are considered and compared in view of their optical reflectance and bandgaps for both TE and TM polarisations. Also, we proposed some heterostructures made by the combination of different Fibonacci generations and their periods to obtain suitable omnidirectional reflection band. We used the transfer matrix method (TMM) to obtain the reflectance, bandgaps and omnidirectional reflectional bandgaps (ODR) of such structures in near infrared spectrum (800-2200 nm) at different angles of incidence. We show that ODR exists in these types of structures. The number of ODRs and total bandgap depend on the Fibonacci generations. Extraordinary ODR bandgaps are obtained in the case of heterostructures formed by the combination of different generations of the Fibonacci sequence. The ODR for these structures is similar to the ODR of photonic crystals containing left-handed materials. This work would be useful to study the Fibonacci type photonic crystals having graded index materials and also it will open new window to design several photonic crystal devices like sensors, reflectors, etc. in the infrared region.

  13. Characterization and thermal stability of cobalt-modified 1-D nanostructured trititanates

    SciTech Connect

    Morgado, Edisson; Abreu, Marco A.S. de

    2009-01-15

    One-dimensional (1-D) nanostructured sodium trititanates were obtained via alkali hydrothermal method and modified with cobalt via ion exchange at different Co concentrations. The resulting cobalt-modified trititanate nanostructures (Co-TTNS) were characterized by TGA, XRD, TEM/SAED, DRS-UV-Vis and N{sub 2} adsorption techniques. Their general chemical formula was estimated as Na{sub x}Co{sub y/2}H{sub 2-x-y}Ti{sub 3}O{sub 7}.nH{sub 2}O and they maintained the same nanostructured and multilayered nature of the sodium precursor, with the growth direction of nanowires and nanotubes along [010]. As a consequence of the Co{sup 2+} incorporation replacing sodium between trititanate layers, two new diffraction lines became prominent and the interlayer distance was reduced with respect to that of the precursor sodium trititanate. Surface area was slightly increased with cobalt intake whereas pore size distribution was hardly affected. Besides, Co{sup 2+} incorporation in trititanate crystal structure also resulted in enhanced visible light photon absorption as indicated by a strong band-gap narrowing. Morphological and structural thermal transformations of Co-TTNS started nearly 400 deg. C in air and the final products after calcination at 800 deg. C were found to be composed of TiO{sub 2}-rutile, CoTiO{sub 3} and a bronze-like phase with general formula Na{sub 2x}Ti{sub 1-x}Co{sub x}O{sub 2}. - Graphical abstract: Co{sup 2+} incorporation in 1D-trititanate crystal nanostructure (Co-TTNS) causes reduction in interlayer distance by comparison with its sodium precursor (Na-TTNS) and leads to enhanced visible light photon absorption efficiency due to a strong band-gap narrowing.

  14. Non-linearity in Bayesian 1-D magnetotelluric inversion

    NASA Astrophysics Data System (ADS)

    Guo, Rongwen; Dosso, Stan E.; Liu, Jianxin; Dettmer, Jan; Tong, Xiaozhong

    2011-05-01

    This paper applies a Bayesian approach to examine non-linearity for the 1-D magnetotelluric (MT) inverse problem. In a Bayesian formulation the posterior probability density (PPD), which combines data and prior information, is interpreted in terms of parameter estimates and uncertainties, which requires optimizing and integrating the PPD. Much work on 1-D MT inversion has been based on (approximate) linearized solutions, but more recently fully non-linear (numerical) approaches have been applied. This paper directly compares results of linearized and non-linear uncertainty estimation for 1-D MT inversion; to do so, advanced methods for both approaches are applied. In the non-linear formulation used here, numerical optimization is carried out using an adaptive-hybrid algorithm. Numerical integration applies Metropolis-Hastings sampling, rotated to a principal-component parameter space for efficient sampling of correlated parameters, and employing non-unity sampling temperatures to ensure global sampling. Since appropriate model parametrizations are generally not known a priori, both under- and overparametrized approaches are considered. For underparametrization, the Bayesian information criterion is applied to determine the number of layers consistent with the resolving power of the data. For overparametrization, prior information is included which favours simple structure in a manner similar to regularized inversion. The data variance and/or trade-off parameter regulating data and prior information are treated in several ways, including applying fixed optimal estimates (an empirical Bayesian approach) or including them as hyperparameters in the sampling (hierarchical Bayesian). The latter approach has the benefit of accounting for the uncertainty in the hyperparameters in estimating model parameter uncertainties. Non-linear and linearized inversion results are compared for synthetic test cases and for the measured COPROD1 MT data by considering marginal probability

  15. Viscous behavior in a quasi-1D fractal cluster glass.

    PubMed

    Etzkorn, S J; Hibbs, Wendy; Miller, Joel S; Epstein, A J

    2002-11-11

    The spin glass transition of a quasi-1D organic-based magnet ([MnTPP][TCNE]) is explored using both ac and dc measurements. A scaling analysis of the ac susceptibility shows a spin glass transition near 4 K, with a viscous decay of the thermoremanent magnetization recorded above 4 K. We propose an extension to a fractal cluster model of spin glasses that determines the dimension of the spin clusters (D) ranging from approximately 0.8 to over 1.5 as the glass transition is approached. Long-range dipolar interactions are suggested as the origin of this low value for the apparent lower critical dimension.

  16. Practical variational tomography for critical 1D systems

    NASA Astrophysics Data System (ADS)

    Lee, Jong Yeon; Landon-Cardinal, Olivier

    2015-03-01

    We further investigate a recently introduced efficient quantum state reconstruction procedure targeted to states well-approximated by the multi-scale entanglement renormalization ansatz (MERA). First, we introduce an improved optimization scheme that can be easily generalized for MERA states with larger bond dimension. Second, we provide a detailed analysis of the error propagation and quantify how it affects the distance between the experimental state and the reconstructed state. Third, we explain how to bound this distance using local data, providing an efficient scalable certification method. Fourth, we examine the performance of MERA tomography on the ground states of several 1D critical models.

  17. Structural stability of a 1D compressible viscoelastic fluid model

    NASA Astrophysics Data System (ADS)

    Huo, Xiaokai; Yong, Wen-An

    2016-07-01

    This paper is concerned with a compressible viscoelastic fluid model proposed by Öttinger. Although the model has a convex entropy, the Hessian matrix of the entropy does not symmetrize the system of first-order partial differential equations due to the non-conservative terms in the constitutive equation. We show that the corresponding 1D model is symmetrizable hyperbolic and dissipative and satisfies the Kawashima condition. Based on these, we prove the global existence of smooth solutions near equilibrium and justify the compatibility of the model with the Navier-Stokes equations.

  18. Nonlocal Order Parameters for the 1D Hubbard Model

    NASA Astrophysics Data System (ADS)

    Montorsi, Arianna; Roncaglia, Marco

    2012-12-01

    We characterize the Mott-insulator and Luther-Emery phases of the 1D Hubbard model through correlators that measure the parity of spin and charge strings along the chain. These nonlocal quantities order in the corresponding gapped phases and vanish at the critical point Uc=0, thus configuring as hidden order parameters. The Mott insulator consists of bound doublon-holon pairs, which in the Luther-Emery phase turn into electron pairs with opposite spins, both unbinding at Uc. The behavior of the parity correlators is captured by an effective free spinless fermion model.

  19. Deconvolution/identification techniques for 1-D transient signals

    SciTech Connect

    Goodman, D.M.

    1990-10-01

    This paper discusses a variety of nonparametric deconvolution and identification techniques that we have developed for application to 1-D transient signal problems. These methods are time-domain techniques that use direct methods for matrix inversion. Therefore, they are not appropriate for large data'' problems. These techniques involve various regularization methods and permit the use of certain kinds of a priori information in estimating the unknown. These techniques have been implemented in a package using standard FORTRAN that should make the package readily transportable to most computers. This paper is also meant to be an instruction manual for the package. 25 refs., 17 figs., 1 tab.

  20. A simple quasi-1D model of Fibonacci anyons

    NASA Astrophysics Data System (ADS)

    Aasen, David; Mong, Roger; Clarke, David; Alicea, Jason; Fendley, Paul

    2015-03-01

    There exists various ways of understanding the topological properties of Ising anyons--from simple free-fermion toy models to formal topological quantum field theory. For other types of anyons simple toy models rarely exist; their properties have to be obtained using formal self-consistency relations. We explore a family of gapped 1D local bosonic models that in a certain limit become trivial to solve and provide an intuitive picture for Fibonacci anyons. One can interpret this model as a quasi-1D wire that forms the building block of a 2D topological phase with Fibonacci anyons. With this interpretation all topological properties of the Fibonacci anyons become manifest including ground state degeneracy and braid relations. We conjecture that the structure of the model is protected by an emergent symmetry analogous to fermion parity. 1) NSF Grant DMR-1341822 2) Institute for Quantum Information and Matter, an NSF physics frontier center with support from the Moore Foundation. 3) NSERC-PGSD.

  1. A 1D analysis of two high order MOC methods

    SciTech Connect

    Everson, M. S.; Forget, B.

    2012-07-01

    The work presented here provides two different methods for evaluating angular fluxes along long characteristics. One is based off a projection of the 1D transport equation onto a complete set of Legendre polynomials, while the other uses the 1D integral transport equation to evaluate the angular flux values at specific points along each track passing through a cell. The Moment Long Characteristic (M-LC) method is shown to provide 2(P+1) spatial convergence and significant gains in accuracy with the addition of only a few spatial degrees of freedom. The M-LC method, though, is shown to be ill-conditioned at very high order and for optically thin geometries. The Point Long Characteristic (P-LC) method, while less accurate, significantly improves stability to problems with optically thin cells. The P-LC method is also more flexible, allowing for extra angular flux evaluations along a given track to give a more accurate representation of the shape along each track. This is at the expense of increasing the degrees of freedom of the system, though, and requires an increase in memory storage. This work concludes that both may be used simultaneously within the same geometry to provide the best mix of accuracy and stability possible. (authors)

  2. Hyperbranched quasi-1D nanostructures for solid-state dye-sensitized solar cells.

    PubMed

    Passoni, Luca; Ghods, Farbod; Docampo, Pablo; Abrusci, Agnese; Martí-Rujas, Javier; Ghidelli, Matteo; Divitini, Giorgio; Ducati, Caterina; Binda, Maddalena; Guarnera, Simone; Li Bassi, Andrea; Casari, Carlo Spartaco; Snaith, Henry J; Petrozza, Annamaria; Di Fonzo, Fabio

    2013-11-26

    In this work we demonstrate hyperbranched nanostructures, grown by pulsed laser deposition, composed of one-dimensional anatase single crystals assembled in arrays of high aspect ratio hierarchical mesostructures. The proposed growth mechanism relies on a two-step process: self-assembly from the gas phase of amorphous TiO2 clusters in a forest of tree-shaped hierarchical mesostructures with high aspect ratio; oriented crystallization of the branches upon thermal treatment. Structural and morphological characteristics can be optimized to achieve both high specific surface area for optimal dye uptake and broadband light scattering thanks to the microscopic feature size. Solid-state dye sensitized solar cells fabricated with arrays of hyperbranched TiO2 nanostructures on FTO-glass sensitized with D102 dye showed a significant 66% increase in efficiency with respect to a reference mesoporous photoanode and reached a maximum efficiency of 3.96% (among the highest reported for this system). This result was achieved mainly thanks to an increase in photogenerated current directly resulting from improved light harvesting efficiency of the hierarchical photoanode. The proposed photoanode overcomes typical limitations of 1D TiO2 nanostructures applied to ss-DSC and emerges as a promising foundation for next-generation high-efficiency solid-state devices comprosed of dyes, polymers, or quantum dots as sensitizers.

  3. Axion string dynamics I: 2+1D

    NASA Astrophysics Data System (ADS)

    Fleury, Leesa M.; Moore, Guy D.

    2016-05-01

    If the axion exists and if the initial axion field value is uncorrelated at causally disconnected points, then it should be possible to predict the efficiency of cosmological axion production, relating the axionic dark matter density to the axion mass. The main obstacle to making this prediction is correctly treating the axion string cores. We develop a new algorithm for treating the axionic string cores correctly in 2+1 dimensions. When the axionic string cores are given their full physical string tension, axion production is about twice as efficient as in previous simulations. We argue that the string network in 2+1 dimensions should behave very differently than in 3+1 dimensions, so this result cannot be simply carried over to the physical case. We outline how to extend our method to 3+1D axion string dynamics.

  4. 1D-transport properties of single superconducting lead nanowires

    NASA Astrophysics Data System (ADS)

    Michotte, S.; Mátéfi-Tempfli, S.; Piraux, L.

    2003-09-01

    We report on the transport properties of single superconducting lead nanowires grown by an electrodeposition technique, embedded in a nanoporous track-etched polymer membrane. The nanowires are granular, have uniform diameter of ∼40 nm and a very large aspect ratio (∼500). The diameter of the nanowire is small enough to ensure a 1D superconducting regime in a wide temperature range below Tc. The non-zero resistance in the superconducting state and its variation caused by fluctuations of the superconducting order parameter were measured versus temperature, magnetic field, and applied DC current (or voltage). The current induced breakdowns in the V- I characteristics may be explained by the formation of phase slip centers. Moreover, DC voltage driven measurements reveal the existence of a new S-shape behavior near the formation of these phase slip centers.

  5. Microlens Masses from 1-D Parallaxes and Heliocentric Proper Motions

    NASA Astrophysics Data System (ADS)

    Gould, Andrew

    2014-12-01

    One-dimensional (1-D) microlens parallaxes can be combined with heliocentric lens-source relative proper motion measurements to derive the lens mass and distance, as suggested by Ghosh et al. (2004). Here I present the first mathematical anlysis of this procedure, which I show can be represented as a quadratic equation. Hence, it is formally subject to a two-fold degeneracy. I show that this degeneracy can be broken in many cases using the relatively crude 2-D parallax information that is often available for microlensing events. I also develop an explicit formula for the region of parameter space where it is more difficult to break this degeneracy. Although no mass/distance measurements have yet been made using this technique, it is likely to become quite common over the next decade.

  6. Quadratic Finite Element Method for 1D Deterministic Transport

    SciTech Connect

    Tolar, Jr., D R; Ferguson, J M

    2004-01-06

    In the discrete ordinates, or SN, numerical solution of the transport equation, both the spatial ({und r}) and angular ({und {Omega}}) dependences on the angular flux {psi}{und r},{und {Omega}}are modeled discretely. While significant effort has been devoted toward improving the spatial discretization of the angular flux, we focus on improving the angular discretization of {psi}{und r},{und {Omega}}. Specifically, we employ a Petrov-Galerkin quadratic finite element approximation for the differencing of the angular variable ({mu}) in developing the one-dimensional (1D) spherical geometry S{sub N} equations. We develop an algorithm that shows faster convergence with angular resolution than conventional S{sub N} algorithms.

  7. Effective theory of black holes in the 1/D expansion

    NASA Astrophysics Data System (ADS)

    Emparan, Roberto; Shiromizu, Tetsuya; Suzuki, Ryotaku; Tanabe, Kentaro; Tanaka, Takahiro

    2015-06-01

    The gravitational field of a black hole is strongly localized near its horizon when the number of dimensions D is very large. In this limit, we can effectively replace the black hole with a surface in a background geometry (e.g. Minkowski or Anti-deSitter space). The Einstein equations determine the effective equations that this `black hole surface' (or membrane) must satisfy. We obtain them up to next-to-leading order in 1/ D for static black holes of the Einstein-(A)dS theory. To leading order, and also to next order in Minkowski backgrounds, the equations of the effective theory are the same as soap-film equations, possibly up to a redshift factor. In particular, the Schwarzschild black hole is recovered as a spherical soap bubble. Less trivially, we find solutions for `black droplets', i.e. black holes localized at the boundary of AdS, and for non-uniform black strings.

  8. Connected components of irreducible maps and 1D quantum phases

    NASA Astrophysics Data System (ADS)

    Szehr, Oleg; Wolf, Michael M.

    2016-08-01

    We investigate elementary topological properties of sets of completely positive (CP) maps that arise in quantum Perron-Frobenius theory. We prove that the set of primitive CP maps of fixed Kraus rank is path-connected and we provide a complete classification of the connected components of irreducible CP maps at given Kraus rank and fixed peripheral spectrum in terms of a multiplicity index. These findings are then applied to analyse 1D quantum phases by studying equivalence classes of translational invariant matrix product states that correspond to the connected components of the respective CP maps. Our results extend the previously obtained picture in that they do not require blocking of physical sites, they lead to analytic paths, and they allow us to decompose into ergodic components and to study the breaking of translational symmetry.

  9. Glycolipid antigen processing for presentation by CD1d molecules.

    PubMed

    Prigozy, T I; Naidenko, O; Qasba, P; Elewaut, D; Brossay, L; Khurana, A; Natori, T; Koezuka, Y; Kulkarni, A; Kronenberg, M

    2001-01-26

    The requirement for processing glycolipid antigens in T cell recognition was examined with mouse CD1d-mediated responses to glycosphingolipids (GSLs). Although some disaccharide GSL antigens can be recognized without processing, the responses to three other antigens, including the disaccharide GSL Gal(alpha1-->2)GalCer (Gal, galactose; GalCer, galactosylceramide), required removal of the terminal sugars to permit interaction with the T cell receptor. A lysosomal enzyme, alpha-galactosidase A, was responsible for the processing of Gal(alpha1-->2)GalCer to generate the antigenic monosaccharide epitope. These data demonstrate a carbohydrate antigen processing system analogous to that used for peptides and an ability of T cells to recognize processed fragments of complex glycolipids.

  10. Roles of TBC1D1 and TBC1D4 in insulin- and exercise-stimulated glucose transport of skeletal muscle

    PubMed Central

    Cartee, Gregory D.

    2014-01-01

    This review focuses on two paralogue Rab GTPase activating proteins known as TBC1D1 Tre-2/BUB2/cdc 1 domain family (TBC1D) 1 and TBC1D4 (also called Akt Substrate of 160 kDa, AS160) and their roles in controlling skeletal muscle glucose transport in response to the independent and combined effects of insulin and exercise. Convincing evidence implicates Akt2-dependent TBC1D4 phosphorylation on T642 as a key part of the mechanism for insulin-stimulated glucose uptake by skeletal muscle. TBC1D1 phosphorylation on several insulin-responsive sites (including T596, a site corresponding to T642 in TBC1D4) does not appear to be essential for in vivo insulin-stimulated glucose uptake by skeletal muscle. In vivo exercise or ex vivo contraction of muscle result in greater TBC1D1 phosphorylation on S237 that is likely to be secondary to increased AMP-activated protein kinase activity and potentially important for contraction-stimulated glucose uptake. Several studies that evaluated both normal and insulin-resistant skeletal muscle stimulated with a physiological insulin concentration after a single exercise session found that greater post-exercise insulin-stimulated glucose uptake was accompanied by greater TBC1D4 phosphorylation on several sites. In contrast, enhanced post-exercise insulin sensitivity was not accompanied by greater insulin-stimulated TBC1D1 phosphorylation. The mechanism for greater TBC1D4 phosphorylation in insulin-stimulated muscles after acute exercise is uncertain, and a causal link between enhanced TBC1D4 phosphorylation and increased post-exercise insulin sensitivity has yet to be established. In summary, TBC1D1 and TBC1D4 have important, but distinct roles in regulating muscle glucose transport in response to insulin and exercise. PMID:25280670

  11. Generation of 1D interference patterns of Bloch surface waves

    NASA Astrophysics Data System (ADS)

    Kadomina, E. A.; Bezus, E. A.; Doskolovich, L. L.

    2016-09-01

    Interference patterns of Bloch surface waves with a period that is significantly less than the wavelength of incident radiation are formed using dielectric diffraction gratings located on the surface of photonic crystal. The simulation based on electromagnetic diffraction theory is used to demonstrate the possibility of high-quality interference patterns due to resonant enhancement of higher evanescent diffraction orders related to the excitation of the Bloch surface waves. The contrast of the interference patterns is close to unity, and the period is less than the period of the diffraction structure by an order of magnitude.

  12. A 1-D evolutionary model for icy satellites, applied to Enceladus

    NASA Astrophysics Data System (ADS)

    Prialnik, Dina; Malamud, Uri

    2015-11-01

    A 1-D long-term evolution code for icy satellites is presented, which couples multiple processes: water migration, geochemical reactions, water and silicate phase transitions, crystallization, compaction by self-gravity, and ablation. The code takes into account various energy sources: tidal heating, radiogenic heating, geochemical energy released by serpentinization or absorbed by mineral dehydration, gravitational energy, and insolation. It includes heat transport by conduction, convection, and advection.The code is applied to Enceladus, by guessing the initial conditions that would render a structure compatible with present-day observations, and adopting a homogeneous initial structure. Assuming that the satellite has been losing water continually along its evolution, it follows that it was formed as a more massive, more ice-rich and more porous object, and gradually transformed into its present day state, due to sustained tidal heating. Several initial compositions and evolution scenarios are considered, and the evolution is simulated for the age of the Solar System. The results corresponding to the present configuration are confronted with the available observational constraints. The present configuration is shown to be differentiated into a pure icy mantle, several tens of km thick, overlying a rocky core, composed of dehydrated rock in the central part and hydrated rock in the outer part. Such a differentiated structure is obtained not only for Enceladus, but for other medium size ice-rich bodies as well.Predictions for Enceladus are a higher rock/ice mass ratio than previously assumed, and a thinner ice mantle, compatible with recent estimates based on gravity field measurements. Although, obviously, the 1-D model cannot be used to explain local phenomena, it sheds light on the internal structure invoked in explanations of localized features and activities.

  13. Single-Crystal-to-Single-Crystal Transformations in One Dimensional Ag-Eu Helical System

    SciTech Connect

    Cai, Yue-Peng; Zhout, Xiu-Xia; Zhout, Zheng-Yuan; Zhu, Shi-Zheng; Thallapally, Praveen K.; Liu, Jun

    2009-07-06

    Single-crystal-to-single-crystal transformation of 1-D 4d-4f coordination polymers have been investigated for the first time. It displays high selectivity for Mg2+ and can be used as magnesium ion-selective luminescent probe. More importantly, we observed the transformation of meso-helical chain to rac-helical chain as a function of temperature.

  14. 1-D Numerical Analysis of RBCC Engine Performance

    NASA Technical Reports Server (NTRS)

    Han, Samuel S.

    1998-01-01

    An RBCC engine combines air breathing and rocket engines into a single engine to increase the specific impulse over an entire flight trajectory. Considerable research pertaining to RBCC propulsion was performed during the 1960's and these engines were revisited recently as a candidate propulsion system for either a single-stage-to-orbit (SSTO) or two-stage-to-orbit (TSTO) launch vehicle. There are a variety of RBCC configurations that had been evaluated and new designs are currently under development. However, the basic configuration of all RBCC systems is built around the ejector scramjet engine originally developed for the hypersonic airplane. In this configuration, a rocket engine plays as an ejector in the air-augmented initial acceleration mode, as a fuel injector in scramjet mode and the rocket in all rocket mode for orbital insertion. Computational fluid dynamics (CFD) is a useful tool for the analysis of complex transport processes in various components in RBCC propulsion systems. The objective of the present research was to develop a transient 1-D numerical model that could be used to predict flow behavior throughout a generic RBCC engine following a flight path.

  15. Dynamic decoupling in the presence of 1D random walk

    NASA Astrophysics Data System (ADS)

    Chakrabarti, Arnab; Chakraborty, Ipsita; Bhattacharyya, Rangeet

    2016-05-01

    In the recent past, many dynamic decoupling sequences have been proposed for the suppression of decoherence of spins connected to thermal baths of various natures. Dynamic decoupling schemes for suppressing decoherence due to Gaussian diffusion have also been developed. In this work, we study the relative performances of dynamic decoupling schemes in the presence of a non-stationary Gaussian noise such as a 1D random walk. Frequency domain analysis is not suitable to determine the performances of various dynamic decoupling schemes in suppressing decoherence due to such a process. Thus, in this work, we follow a time domain calculation to arrive at the following conclusions: in the presence of such a noise, we show that (i) the traditional Carr–Purcell–Meiboom–Gill (CPMG) sequence outperforms Uhrig’s dynamic decoupling scheme, (ii) CPMG remains the optimal sequence for suppression of decoherence due to random walk in the presence of an external field gradient. Later, the theoretical predictions are experimentally verified by using nuclear magnetic resonance spectroscopy on spin 1/2 particles diffusing in a liquid medium.

  16. Control and imaging of O(1D2) precession

    NASA Astrophysics Data System (ADS)

    Wu, Shiou-Min; Radenovic, Dragana Č.; van der Zande, Wim J.; Groenenboom, Gerrit C.; Parker, David H.; Vallance, Claire; Zare, Richard N.

    2011-01-01

    Larmor precession of a quantum mechanical angular momentum vector about an applied magnetic field forms the basis for a range of magnetic resonance techniques, including nuclear magnetic resonance spectroscopy and magnetic resonance imaging. We have used a polarized laser pump-probe scheme with velocity-map imaging detection to visualize, for the first time, the precessional motion of a quantum mechanical angular momentum vector. Photodissociation of O2 at 157 nm provides a clean source of fast-moving O(1D2) atoms, with their electronic angular momentum vector strongly aligned perpendicular to the recoil direction. In the presence of an external magnetic field, the distribution of atomic angular momenta precesses about the field direction, and polarization-sensitive images of the atomic scattering distribution recorded as a function of field strength yield ‘time-lapse-photography’ style movies of the precessional motion. We present movies recorded in various experimental geometries, and discuss potential consequences and applications in atmospheric chemistry and reaction dynamics.

  17. Crystal Creations.

    ERIC Educational Resources Information Center

    Whipple, Nona; Whitmore, Sherry

    1989-01-01

    Presents a many-faceted learning approach to the study of crystals. Provides instructions for performing activities including crystal growth and patterns, creating miniature simulations of crystal-containing rock formations, charcoal and sponge gardens, and snowflakes. (RT)

  18. Absolute rate constant determinations for the deactivation of O/1D/ by time resolved decay of O/1D/ yields O/3P/ emission

    NASA Technical Reports Server (NTRS)

    Davidson, J. A.; Sadowski, C. M.; Schiff, H. I.; Howard, C. J.; Schmeltekopf, A. L.; Jennings, D. A.; Streit, G. E.

    1976-01-01

    Absolute rate constants for the deactivation of O(1D) atoms by some atmospheric gases have been determined by observing the time-resolved emission of O(1D) at 630 nm. O(1D) atoms were produced by the dissociation of ozone via repetitive laser pulses at 266 nm. Absolute rate constants for the relaxation of O(1D) at 298 K are reported for N2, O2, CO2, O3, H2, D2, CH4, HCl, NH3, H2O, N2O, and Ne. The results obtained are compared with previous relative and absolute measurements reported in the literature.

  19. Structure-based design of novel Chlamydomonas reinhardtii D1-D2 photosynthetic proteins for herbicide monitoring

    PubMed Central

    Rea, Giuseppina; Polticelli, Fabio; Antonacci, Amina; Scognamiglio, Viviana; Katiyar, Prashant; Kulkarni, Sudhir A; Johanningmeier, Udo; Giardi, Maria Teresa

    2009-01-01

    The D1-D2 heterodimer in the reaction center core of phototrophs binds the redox plastoquinone cofactors, QA and QB, the terminal acceptors of the photosynthetic electron transfer chain in the photosystem II (PSII). This complex is the target of the herbicide atrazine, an environmental pollutant competitive inhibitor of QB binding, and consequently it represents an excellent biomediator to develop biosensors for pollutant monitoring in ecosystems. In this context, we have undertaken a study of the Chlamydomonas reinhardtii D1-D2 proteins aimed at designing site directed mutants with increased affinity for atrazine. The three-dimensional structure of the D1 and D2 proteins from C. reinhardtii has been homology modeled using the crystal structure of the highly homologous Thermosynechococcus elongatus proteins as templates. Mutants of D1 and D2 were then generated in silico and the atrazine binding affinity of the mutant proteins has been calculated to predict mutations able to increase PSII affinity for atrazine. The computational approach has been validated through comparison with available experimental data and production and characterization of one of the predicted mutants. The latter analyses indicated an increase of one order of magnitude of the mutant sensitivity and affinity for atrazine as compared to the control strain. Finally, D1-D2 heterodimer mutants were designed and selected which, according to our model, increase atrazine binding affinity by up to 20 kcal/mol, representing useful starting points for the development of high affinity biosensors for atrazine. PMID:19693932

  20. Evidence against dopamine D1/D2 receptor heteromers

    PubMed Central

    Frederick, Aliya L.; Yano, Hideaki; Trifilieff, Pierre; Vishwasrao, Harshad D.; Biezonski, Dominik; Mészáros, József; Sibley, David R.; Kellendonk, Christoph; Sonntag, Kai C.; Graham, Devon L.; Colbran, Roger J.; Stanwood, Gregg D.; Javitch, Jonathan A.

    2014-01-01

    Hetero-oligomers of G-protein-coupled receptors have become the subject of intense investigation because their purported potential to manifest signaling and pharmacological properties that differ from the component receptors makes them highly attractive for the development of more selective pharmacological treatments. In particular, dopamine D1 and D2 receptors have been proposed to form hetero-oligomers that couple to Gαq proteins, and SKF83959 has been proposed to act as a biased agonist that selectively engages these receptor complexes to activate Gαq and thus phospholipase C. D1/D2 heteromers have been proposed as relevant to the pathophysiology and treatment of depression and schizophrenia. We used in vitro bioluminescence resonance energy transfer (BRET), ex vivo analyses of receptor localization and proximity in brain slices, and behavioral assays in mice to characterize signaling from these putative dimers/oligomers. We were unable to detect Gαq or Gα11 protein coupling to homomers or heteromers of D1 or D2 receptors using a variety of biosensors. SKF83959-induced locomotor and grooming behaviors were eliminated in D1 receptor knockout mice, verifying a key role for D1-like receptor activation. In contrast, SKF83959-induced motor responses were intact in D2 receptor and Gαq knockout mice, as well as in knock-in mice expressing a mutant Ala286-CaMKIIα, that cannot autophosphorylate to become active. Moreover, we found that in the shell of the nucleus accumbens, even in neurons in which D1 and D2 receptor promoters are both active, the receptor proteins are segregated and do not form complexes. These data are not compatible with SKF83959 signaling through Gαq or through a D1–D2 heteromer and challenge the existence of such a signaling complex in the adult animals that we used for our studies. PMID:25560761

  1. Dynamical functions of a 1D correlated quantum liquid

    NASA Astrophysics Data System (ADS)

    Carmelo, J. M. P.; Bozi, D.; Penc, K.

    2008-10-01

    The dynamical correlation functions in one-dimensional electronic systems show power-law behaviour at low energies and momenta close to integer multiples of the charge and spin Fermi momenta. These systems are usually referred to as Tomonaga-Luttinger liquids. However, near well defined lines of the (k,ω) plane the power-law behaviour extends beyond the low-energy cases mentioned above, and also appears at higher energies, leading to singular features in the photoemission spectra and other dynamical correlation functions. The general spectral-function expressions derived in this paper were used in recent theoretical studies of the finite-energy singular features in photoemission of the organic compound tetrathiafulvalene-tetracyanoquinodimethane (TTF-TCNQ) metallic phase. They are based on a so-called pseudofermion dynamical theory (PDT), which allows us to systematically enumerate and describe the excitations in the Hubbard model starting from the Bethe ansatz, as well as to calculate the charge and spin object phase shifts appearing as exponents of the power laws. In particular, we concentrate on the spin-density m\\rightarrow 0 limit and on effects in the vicinity of the singular border lines, as well as close to half filling. Our studies take into account spectral contributions from types of microscopic processes that do not occur for finite values of the spin density. In addition, the specific processes involved in the spectral features of TTF-TCNQ are studied. Our results are useful for the further understanding of the unusual spectral properties observed in low-dimensional organic metals and also provide expressions for the one- and two-atom spectral functions of a correlated quantum system of ultracold fermionic atoms in a 1D optical lattice with on-site two-atom repulsion.

  2. Synthesis, characterization, and physical properties of 1D nanostructures

    NASA Astrophysics Data System (ADS)

    Marley, Peter Mchael

    The roster of materials exhibiting metal---insulator transitions with sharply discontinuous switching of electrical conductivity close to room temperature remains rather sparse despite the fundamental interest in the electronic instabilities manifested in such materials and the plethora of potential technological applications, ranging from frequency-agile metamaterials to electrochromic coatings and Mott field-effect transistors. Vanadium oxide bronzes with the general formula MxV2O 5, provide a wealth of compositions and frameworks where strong electron correlation can be systematically (albeit thus far only empirically) tuned. Charge fluctuations along the quasi-1D frameworks of MxV 2O5 bronzes have evinced much recent interest owing to the manifestation of colossal metal---insulator transitions and superconductivity. We start with a general review on the phase transitions, both electronic and structural, of vanadium oxide bronzes in Chapter 1. In Chapter 2, we demonstrate an unprecedented reversible transformation between double-layered (delta) and tunnel (beta) quasi-1D geometries for nanowires of a divalent vanadium bronze CaxV2O5 (x ˜0.23) upon annealing-induced dehydration and hydrothermally-induced hydration. Such a facile hydration/dehydration-induced interconversion between two prominent quasi-1D structures (accompanied by a change in charge ordering motifs) has not been observed in the bulk and is posited to result from the ease of propagation of crystallographic slip processes across the confined nanowire widths for the delta→beta conversion and the facile diffusion of water molecules within the tunnel geometries for the beta→delta reversion. We demonstrate in Chapter 3 unprecedented pronounced metal-insulator transitions induced by application of a voltage for nanowires of a vanadium oxide bronze with intercalated divalent cations, beta-PbxV 2O5 (x ˜0.33). The induction of the phase transition through application of an electric field at room

  3. Synthesis, characterization, and physical properties of 1D nanostructures

    NASA Astrophysics Data System (ADS)

    Marley, Peter Mchael

    The roster of materials exhibiting metal---insulator transitions with sharply discontinuous switching of electrical conductivity close to room temperature remains rather sparse despite the fundamental interest in the electronic instabilities manifested in such materials and the plethora of potential technological applications, ranging from frequency-agile metamaterials to electrochromic coatings and Mott field-effect transistors. Vanadium oxide bronzes with the general formula MxV2O 5, provide a wealth of compositions and frameworks where strong electron correlation can be systematically (albeit thus far only empirically) tuned. Charge fluctuations along the quasi-1D frameworks of MxV 2O5 bronzes have evinced much recent interest owing to the manifestation of colossal metal---insulator transitions and superconductivity. We start with a general review on the phase transitions, both electronic and structural, of vanadium oxide bronzes in Chapter 1. In Chapter 2, we demonstrate an unprecedented reversible transformation between double-layered (delta) and tunnel (beta) quasi-1D geometries for nanowires of a divalent vanadium bronze CaxV2O5 (x ˜0.23) upon annealing-induced dehydration and hydrothermally-induced hydration. Such a facile hydration/dehydration-induced interconversion between two prominent quasi-1D structures (accompanied by a change in charge ordering motifs) has not been observed in the bulk and is posited to result from the ease of propagation of crystallographic slip processes across the confined nanowire widths for the delta→beta conversion and the facile diffusion of water molecules within the tunnel geometries for the beta→delta reversion. We demonstrate in Chapter 3 unprecedented pronounced metal-insulator transitions induced by application of a voltage for nanowires of a vanadium oxide bronze with intercalated divalent cations, beta-PbxV 2O5 (x ˜0.33). The induction of the phase transition through application of an electric field at room

  4. SCCRO3 (DCUN1D3) Antagonizes the Neddylation and Oncogenic Activity of SCCRO (DCUN1D1)*

    PubMed Central

    Huang, Guochang; Stock, Cameron; Bommeljé, Claire C.; Weeda, Víola B.; Shah, Kushyup; Bains, Sarina; Buss, Elizabeth; Shaha, Manish; Rechler, Willi; Ramanathan, Suresh Y.; Singh, Bhuvanesh

    2014-01-01

    The activity of cullin-RING type ubiquitination E3 ligases is regulated by neddylation, a process analogous to ubiquitination that culminates in covalent attachment of the ubiquitin-like protein Nedd8 to cullins. As a component of the E3 for neddylation, SCCRO/DCUN1D1 plays a key regulatory role in neddylation and, consequently, cullin-RING ligase activity. The essential contribution of SCCRO to neddylation is to promote nuclear translocation of the cullin-ROC1 complex. The presence of a myristoyl sequence in SCCRO3, one of four SCCRO paralogues present in humans that localizes to the membrane, raises questions about its function in neddylation. We found that although SCCRO3 binds to CAND1, cullins, and ROC1, it does not efficiently bind to Ubc12, promote cullin neddylation, or conform to the reaction processivity paradigms, suggesting that SCCRO3 does not have E3 activity. Expression of SCCRO3 inhibits SCCRO-promoted neddylation by sequestering cullins to the membrane, thereby blocking its nuclear translocation. Moreover, SCCRO3 inhibits SCCRO transforming activity. The inhibitory effects of SCCRO3 on SCCRO-promoted neddylation and transformation require both an intact myristoyl sequence and PONY domain, confirming that membrane localization and binding to cullins are required for in vivo functions. Taken together, our findings suggest that SCCRO3 functions as a tumor suppressor by antagonizing the neddylation activity of SCCRO. PMID:25349211

  5. Synthesis, characterization and comparison of polyaniline 1D-structure controlled by poly(L-lactide) and poly(D-lactide)

    NASA Astrophysics Data System (ADS)

    Gu, Zhou-Jie; Shen, Qing

    2016-01-01

    1D-structural polyaniline (PANI) was controllably synthesized by utilizing the poly(L-lactide) (PLLA) and poly(D-lactide) (PDLA) as controllers. FESEM images showed that the morphology of 1D-structural PANI controlled by PDLA likes a joint obviously unlike PLLA controlled vertebra structure reported previously. To set the ratio of ANI/PLLA (ml/g) at 0.45/0.135, 0.45/0.270 and 0.45/0.540, the formed PANI 1D structure was changed in the cross-section as four round leaves, four non-round leaves and four sharp leaves, respectively. FTIR and XRD analysis indicated that the PLLA and PDLA both were doped in PANI chains while the PLLA was strongly in the electrons delocalization than that of the PDLA due probably to the L-type stronger in crystal polymorphism than that of the D-type.

  6. 1-D Tremor Streaks: Implications for a Streak Source Model

    NASA Astrophysics Data System (ADS)

    Houston, H.; Ghosh, A.; Vidale, J. E.

    2009-12-01

    Recent observations of non-volcanic tremor in Cascadia and Japan show “streaks” of tremor moving up and down dip in a convergence-parallel direction at “driving velocities” (i.e., 30 to 120 km/hr). Streak lengths of 30 to 40 km are occasionally observed. We explore the implications of these observations for a source model and spectrum of tremor. Key elements involve the extreme geometry and slow “rupture velocity” implied by the streaks. The source spectrum of tremor and other ETS seismic radiation exhibits a spectral falloff roughly as the inverse of frequency (1/f) in contrast to that of earthquakes, which follow a spectral falloff of 1/f squared above a corner frequency. Nevertheless, several observations suggest that the deformation that generates tremor is shear slip in the plate convergence direction. A fundamental question, then, has been what slip source could produce such an observed 1/f falloff over a wide frequency range. We propose a kinematic model, consistent with the 1-D geometry of the tremor streaks, in which fault displacement and width are strongly limited and rupture growth occurs only along fault length, which is oriented in a convergence-parallel direction (up or down dip). This is a version of the well-known Haskell model in which the durations of the two boxcars are very different. A 1/f spectral falloff holds between the corner frequencies associated with the two durations. Thus, the frequency range of the observed 1/f spectral falloff of tremor provides constraints on the durations of the boxcars. Further constraints involve the maximum likely displacement in an ETS event, the rupture velocities of the streaks, and the moment release rate. The narrow streak geometry implies fairly high strain and stress drops, in contrast to the low overall stress drops inferred from tidal modulation of tremor and the low strain across the entire ETS region. The observation of tremor streaks migrating at 10's of km/hour, in conjunction with the

  7. Human CD1d knock-in mouse model demonstrates potent antitumor potential of human CD1d-restricted invariant natural killer T cells

    PubMed Central

    Wen, Xiangshu; Rao, Ping; Carreño, Leandro J.; Kim, Seil; Lawrenczyk, Agnieszka; Porcelli, Steven A.; Cresswell, Peter; Yuan, Weiming

    2013-01-01

    Despite a high degree of conservation, subtle but important differences exist between the CD1d antigen presentation pathways of humans and mice. These differences may account for the minimal success of natural killer T (NKT) cell-based antitumor therapies in human clinical trials, which contrast strongly with the powerful antitumor effects in conventional mouse models. To develop an accurate model for in vivo human CD1d (hCD1d) antigen presentation, we have generated a hCD1d knock-in (hCD1d-KI) mouse. In these mice, hCD1d is expressed in a native tissue distribution pattern and supports NKT cell development. Reduced numbers of invariant NKT (iNKT) cells were observed, but at an abundance comparable to that in most normal humans. These iNKT cells predominantly expressed mouse Vβ8, the homolog of human Vβ11, and phenotypically resembled human iNKT cells in their reduced expression of CD4. Importantly, iNKT cells in hCD1d knock-in mice exert a potent antitumor function in a melanoma challenge model. Our results show that replacement of mCD1d by hCD1d can select a population of functional iNKT cells closely resembling human iNKT cells. These hCD1d knock-in mice will allow more accurate in vivo modeling of human iNKT cell responses and will facilitate the preclinical assessment of iNKT cell-targeted antitumor therapies. PMID:23382238

  8. Isostructural 1D coordination polymers of Zn(II), Cd(II) and Cu(II) with phenylpropynoic acid and DABCO as organic linkers

    NASA Astrophysics Data System (ADS)

    Saravanakumar, Rajendran; Varghese, Babu; Sankararaman, Sethuraman

    2014-11-01

    Using phenylpropynoic acid (PPA) and 1,4-diazabicyclo[2.2.2]octane (DABCO) as organic spacers, isostructural coordination polymers of Zn(II), Cd(II) and Cu(II) were synthesized by solvothermal method and structurally characterized using single crystal XRD, powder XRD, 13C CP-MAS NMR spectroscopy. Single crystal XRD data revealed four PPA units coordinating with two metal ions forming a paddle wheel secondary building unit (SBU). The paddle wheel units are connected through coordination of DABCO nitrogen to the metal centers from the axial positions leading to the formation of the 1D coordination polymers along the c axis. Intermolecular π stacking and Csbnd H…π interactions between the adjacent polymer chains convert the 1D coordination polymer into an interesting 3D network with the Csbnd H…π bonds running along the crystallographic a and b axes. Thermal and nitrogen adsorption studies of these coordination polymers are reported.

  9. Role of the D1-D2 Linker of Human VCP/p97 in the Asymmetry and ATPase Activity of the D1-domain

    PubMed Central

    Tang, Wai Kwan; Xia, Di

    2016-01-01

    Human AAA+ protein p97 consists of an N-domain and two tandem ATPase domains D1 and D2, which are connected by the N-D1 and the D1-D2 linkers. Inclusion of the D1-D2 linker, a 22-amino acid peptide, at the end of p97 N-D1 truncate has been shown to activate ATP hydrolysis of its D1-domain, although the mechanism of activation remains unclear. Here, we identify the N-terminal half of this linker, highly conserved from human to fungi, is essential for the ATPase activation. By analyzing available crystal structures, we observed that the D1-D2 linker is capable of inducing asymmetry in subunit association into a p97 hexamer. This observation is reinforced by two new crystal structures, determined in the present work. The effect of D1-D2 linker on the ATPase activity of the D1-domain is correlated to the side-chain conformation of residue R359, a trans-acting arginine-finger residue essential for ATP hydrolysis of the D1-domain. The activation in D1-domain ATPase activity by breaking perfect six-fold symmetry implies functional importance of asymmetric association of p97 subunits, the extent of which can be determined quantitatively by the metric Asymmetric Index. PMID:26818443

  10. Proteasome-mediated degradation antagonizes critical levels of the apoptosis-inducing C1D protein

    PubMed Central

    Rothbarth, Karsten; Stammer, Hermann; Werner, Dieter

    2002-01-01

    The C1D gene is expressed in a broad spectrum of mammalian cells and tissues but its product induces apoptotic cell death when exceeding a critical level. Critical levels are achieved in a fraction of cells by transient transfection with EGFP-tagged C1D expression constructs. However, transfected cells expressing sub-critical levels of C1D(EGFP) escape apoptotic cell death by activation of a proteasome-mediated rescue mechanism. Inhibition of the proteasome-dependent degradation of the C1D(EGFP) protein results in a parallel increase of the intracellular C1D level and in the fraction of apoptotic cells. PMID:12379155

  11. Grid Cell Responses in 1D Environments Assessed as Slices through a 2D Lattice.

    PubMed

    Yoon, KiJung; Lewallen, Sam; Kinkhabwala, Amina A; Tank, David W; Fiete, Ila R

    2016-03-01

    Grid cells, defined by their striking periodic spatial responses in open 2D arenas, appear to respond differently on 1D tracks: the multiple response fields are not periodically arranged, peak amplitudes vary across fields, and the mean spacing between fields is larger than in 2D environments. We ask whether such 1D responses are consistent with the system's 2D dynamics. Combining analytical and numerical methods, we show that the 1D responses of grid cells with stable 1D fields are consistent with a linear slice through a 2D triangular lattice. Further, the 1D responses of comodular cells are well described by parallel slices, and the offsets in the starting points of the 1D slices can predict the measured 2D relative spatial phase between the cells. From these results, we conclude that the 2D dynamics of these cells is preserved in 1D, suggesting a common computation during both types of navigation behavior. PMID:26898777

  12. Crystal Systems.

    ERIC Educational Resources Information Center

    Schomaker, Verner; Lingafelter, E. C.

    1985-01-01

    Discusses characteristics of crystal systems, comparing (in table format) crystal systems with lattice types, number of restrictions, nature of the restrictions, and other lattices that can accidently show the same metrical symmetry. (JN)

  13. Virtual Crystallizer

    SciTech Connect

    Land, T A; Dylla-Spears, R; Thorsness, C B

    2006-08-29

    Large dihydrogen phosphate (KDP) crystals are grown in large crystallizers to provide raw material for the manufacture of optical components for large laser systems. It is a challenge to grow crystal with sufficient mass and geometric properties to allow large optical plates to be cut from them. In addition, KDP has long been the canonical solution crystal for study of growth processes. To assist in the production of the crystals and the understanding of crystal growth phenomena, analysis of growth habits of large KDP crystals has been studied, small scale kinetic experiments have been performed, mass transfer rates in model systems have been measured, and computational-fluid-mechanics tools have been used to develop an engineering model of the crystal growth process. The model has been tested by looking at its ability to simulate the growth of nine KDP boules that all weighed more than 200 kg.

  14. Crystal growing

    NASA Technical Reports Server (NTRS)

    Neville, J. P.

    1990-01-01

    One objective is to demonstrate the way crystals grow and how they affect the behavior of material. Another objective is to compare the growth of crystals in metals and nonmetals. The procedures, which involve a supersaturated solution of a salt that will separate into crystals on cooling and the pouring off of an eutectic solution to expose the crystals formed by a solid solution when an alloy of two metals forms a solid and eutectic solution on cooling, are described.

  15. Expression of CD1d protein in human testis showing normal and abnormal spermatogenesis.

    PubMed

    Adly, Mohamed A; Abdelwahed Hussein, Mahmoud-Rezk

    2011-05-01

    CD1d is a member of CD1 family of transmembrane glycoproteins, which represent antigen-presenting molecules. Immunofluorescent staining methods were utilized to examine expression pattern of CD1d in human testicular specimens. In testis showing normal spermatogenesis, a strong CD1d cytoplasmic expression was seen the Sertoli cells, spermatogonia, and Leydig cells. A moderate expression was observed in the spermatocytes. In testes showing maturation arrest, CD1d expression was strong in the Sertoli cells and weak in spermatogonia and spermatocytes compared to testis with normal spermatogenesis. In Sertoli cell only syndrome, CD1d expression was strong in the Sertoli and Leydig cells. This preliminary study displayed testicular infertility-related changes in CD1d expression. The ultrastructural changes associated with with normal and abnormal spermatogenesis are open for further investigations.

  16. Examination of 1D Solar Cell Model Limitations Using 3D SPICE Modeling: Preprint

    SciTech Connect

    McMahon, W. E.; Olson, J. M.; Geisz, J. F.; Friedman, D. J.

    2012-06-01

    To examine the limitations of one-dimensional (1D) solar cell modeling, 3D SPICE-based modeling is used to examine in detail the validity of the 1D assumptions as a function of sheet resistance for a model cell. The internal voltages and current densities produced by this modeling give additional insight into the differences between the 1D and 3D models.

  17. Exercise increases TBC1D1 phosphorylation in human skeletal muscle

    PubMed Central

    Jessen, Niels; An, Ding; Lihn, Aina S.; Nygren, Jonas; Hirshman, Michael F.; Thorell, Anders

    2011-01-01

    Exercise and weight loss are cornerstones in the treatment and prevention of type 2 diabetes, and both interventions function to increase insulin sensitivity and glucose uptake into skeletal muscle. Studies in rodents demonstrate that the underlying mechanism for glucose uptake in muscle involves site-specific phosphorylation of the Rab-GTPase-activating proteins AS160 (TBC1D4) and TBC1D1. Multiple kinases, including Akt and AMPK, phosphorylate TBC1D1 and AS160 on distinct residues, regulating their activity and allowing for GLUT4 translocation. In contrast to extensive rodent-based studies, the regulation of AS160 and TBC1D1 in human skeletal muscle is not well understood. In this study, we determined the effects of dietary intervention and a single bout of exercise on TBC1D1 and AS160 site-specific phosphorylation in human skeletal muscle. Ten obese (BMI 33.4 ± 2.4, M-value 4.3 ± 0.5) subjects were studied at baseline and after a 2-wk dietary intervention. Muscle biopsies were obtained from the subjects in the resting (basal) state and immediately following a 30-min exercise bout (70% V̇o2 max). Muscle lysates were analyzed for AMPK activity and Akt phosphorylation and for TBC1D1 and AS160 phosphorylation on known or putative AMPK and Akt sites as follows: AS160 Ser711 (AMPK), TBC1D1 Ser231 (AMPK), TBC1D1 Ser660 (AMPK), TBC1D1 Ser700 (AMPK), and TBC1D1 Thr590 (Akt). The diet intervention that consisted of a major shift in the macronutrient composition resulted in a 4.2 ± 0.4 kg weight loss (P < 0.001) and a significant increase in insulin sensitivity (M value 5.6 ± 0.6), but surprisingly, there was no effect on expression or phosphorylation of any of the muscle-signaling proteins. Exercise increased muscle AMPKα2 activity but did not increase Akt phosphorylation. Exercise increased phosphorylation on AS160 Ser711, TBC1D1 Ser231, and TBC1D1 Ser660 but had no effect on TBC1D1 Ser700. Exercise did not increase TBC1D1 Thr590 phosphorylation or TBC1D1/AS160 PAS

  18. Structural variation from heterometallic cluster-based 1D chain to heterometallic tetranuclear cluster: Syntheses, structures and magnetic properties

    NASA Astrophysics Data System (ADS)

    Zhang, Shu-Hua; Zhao, Ru-Xia; Li, He-Ping; Ge, Cheng-Min; Li, Gui; Huang, Qiu-Ping; Zou, Hua-Hong

    2014-08-01

    Using the solvothermal method, we present the comparative preparation of {[Co3Na(dmaep)3(ehbd)(N3)3]·DMF}n (1) and [Co2Na2(hmbd)4(N3)2(DMF)2] (2), where Hehbd is 3-ethoxy-2-hydroxy-benzaldehyde, Hhmbd is 3-methoxy-2-hydroxy-benzaldehyde, and Hdmaep is 2-dimethylaminomethyl-6-ethoxy-phenol, which was synthesized by an in-situ reaction. Complexes 1 and 2 were characterized by elemental analysis, IR spectroscopy, and X-ray single-crystal diffraction. Complex 1 is a novel heterometallic cluster-based 1-D chain and 2 is a heterometallic tetranuclear cluster. The {Co3IINa} and {Co2IINa2} cores display dominant ferromagnetic interaction from the nature of the binding modes through μ1,1,1-N3- (end-on, EO).

  19. Potent neutralizing anti-CD1d antibody reduces lung cytokine release in primate asthma model.

    PubMed

    Nambiar, Jonathan; Clarke, Adam W; Shim, Doris; Mabon, David; Tian, Chen; Windloch, Karolina; Buhmann, Chris; Corazon, Beau; Lindgren, Matilda; Pollard, Matthew; Domagala, Teresa; Poulton, Lynn; Doyle, Anthony G

    2015-01-01

    CD1d is a receptor on antigen-presenting cells involved in triggering cell populations, particularly natural killer T (NKT) cells, to release high levels of cytokines. NKT cells are implicated in asthma pathology and blockade of the CD1d/NKT cell pathway may have therapeutic potential. We developed a potent anti-human CD1d antibody (NIB.2) that possesses high affinity for human and cynomolgus macaque CD1d (KD ∼100 pM) and strong neutralizing activity in human primary cell-based assays (IC50 typically <100 pM). By epitope mapping experiments, we showed that NIB.2 binds to CD1d in close proximity to the interface of CD1d and the Type 1 NKT cell receptor β-chain. Together with data showing that NIB.2 inhibited stimulation via CD1d loaded with different glycolipids, this supports a mechanism whereby NIB.2 inhibits NKT cell activation by inhibiting Type 1 NKT cell receptor β-chain interactions with CD1d, independent of the lipid antigen in the CD1d antigen-binding cleft. The strong in vitro potency of NIB.2 was reflected in vivo in an Ascaris suum cynomolgus macaque asthma model. Compared with vehicle control, NIB.2 treatment significantly reduced bronchoalveolar lavage (BAL) levels of Ascaris-induced cytokines IL-5, IL-8 and IL-1 receptor antagonist, and significantly reduced baseline levels of GM-CSF, IL-6, IL-15, IL-12/23p40, MIP-1α, MIP-1β, and VEGF. At a cellular population level NIB.2 also reduced numbers of BAL lymphocytes and macrophages, and blood eosinophils and basophils. We demonstrate that anti-CD1d antibody blockade of the CD1d/NKT pathway modulates inflammatory parameters in vivo in a primate inflammation model, with therapeutic potential for diseases where the local cytokine milieu is critical.

  20. Potent neutralizing anti-CD1d antibody reduces lung cytokine release in primate asthma model

    PubMed Central

    Nambiar, Jonathan; Clarke, Adam W; Shim, Doris; Mabon, David; Tian, Chen; Windloch, Karolina; Buhmann, Chris; Corazon, Beau; Lindgren, Matilda; Pollard, Matthew; Domagala, Teresa; Poulton, Lynn; Doyle, Anthony G

    2015-01-01

    CD1d is a receptor on antigen-presenting cells involved in triggering cell populations, particularly natural killer T (NKT) cells, to release high levels of cytokines. NKT cells are implicated in asthma pathology and blockade of the CD1d/NKT cell pathway may have therapeutic potential. We developed a potent anti-human CD1d antibody (NIB.2) that possesses high affinity for human and cynomolgus macaque CD1d (KD ∼100 pM) and strong neutralizing activity in human primary cell-based assays (IC50 typically <100 pM). By epitope mapping experiments, we showed that NIB.2 binds to CD1d in close proximity to the interface of CD1d and the Type 1 NKT cell receptor β-chain. Together with data showing that NIB.2 inhibited stimulation via CD1d loaded with different glycolipids, this supports a mechanism whereby NIB.2 inhibits NKT cell activation by inhibiting Type 1 NKT cell receptor β-chain interactions with CD1d, independent of the lipid antigen in the CD1d antigen-binding cleft. The strong in vitro potency of NIB.2 was reflected in vivo in an Ascaris suum cynomolgus macaque asthma model. Compared with vehicle control, NIB.2 treatment significantly reduced bronchoalveolar lavage (BAL) levels of Ascaris-induced cytokines IL-5, IL-8 and IL-1 receptor antagonist, and significantly reduced baseline levels of GM-CSF, IL-6, IL-15, IL-12/23p40, MIP-1α, MIP-1β, and VEGF. At a cellular population level NIB.2 also reduced numbers of BAL lymphocytes and macrophages, and blood eosinophils and basophils. We demonstrate that anti-CD1d antibody blockade of the CD1d/NKT pathway modulates inflammatory parameters in vivo in a primate inflammation model, with therapeutic potential for diseases where the local cytokine milieu is critical. PMID:25751125

  1. Electronic-to-vibrational energy transfer efficiency in the O/1 D/-N2 and O/1 D/-CO systems

    NASA Technical Reports Server (NTRS)

    Slanger, T. G.; Black, G.

    1974-01-01

    With the aid of a molecular resonance fluorescence technique, which utilizes optical pumping from the v = 1 level of the ground state of CO by A 1 Pi-X 1 Sigma radiation, a study is made of the efficiency of E-V transfer from O(1 D) to CO. O(1 D) is generated at a known rate by O2 photodissociation at 1470 A in an intermittent mode, and the small modulation of the fluorescent signal associated with CO (v = 1) above the normal thermal background is interpreted in terms of E-V transfer efficiency. The CO (v = 1) lifetime in this system is determined mainly by resonance trapping of the IR fundamental band, and is found to be up to ten times longer than the natural radiative lifetime. For CO, (40 plus or minus 8)% of the O(1 D) energy is converted into vibrational energy. By observing the effect of N2 on the CO (v = 1) fluorescent intensity and lifetime, it is possible to obtain the E-V transfer efficiency for the system O(1 D)-N2 relative to that for O(1 D)-CO. The results indicate that the efficiency for N2 is (83 plus or minus 10)% of that for CO.

  2. Mapping of the serotonin 5-HT{sub 1D{alpha}} autoreceptor gene (HTR1D) on chromosome 1 using a silent polymorphism in the coding region

    SciTech Connect

    Ozaki, N.; Lappalainen, J.; Linnoila, M.

    1995-04-24

    Serotonin (5-HT){sub ID} receptors are 5-HT release-regulating autoreceptors in the human brain. Abnormalities in brain 5-HT function have been hypothesized in the pathophysiology of various psychiatric disorders, including obsessive-compulsive disorder, autism, mood disorders, eating disorders, impulsive violent behavior, and alcoholism. Thus, mutations occurring in 5-HT autoreceptors may cause or increase the vulnerability to any of these conditions. 5-HT{sub 1D{alpha}} and 5-HT{sub 1D{Beta}} subtypes have been previously localized to chromosomes 1p36.3-p34.3 and 6q13, respectively, using rodent-human hybrids and in situ localization. In this communication, we report the detection of a 5-HT{sub 1D{alpha}} receptor gene polymorphism by single strand conformation polymorphism (SSCP) analysis of the coding sequence. The polymorphism was used for fine scale linkage mapping of 5-HT{sub 1D{alpha}} on chromosome 1. This polymorphism should also be useful for linkage studies in populations and in families. Our analysis also demonstrates that functionally significant coding sequence variants of the 5-HT{sub 1D{alpha}} are probably not abundant either among alcoholics or in the general population. 14 refs., 1 fig., 1 tab.

  3. Neodymium 1D systems: targeting new sources for field-induced slow magnetization relaxation.

    PubMed

    Jassal, Amanpreet Kaur; Aliaga-Alcalde, Núria; Corbella, Montserrat; Aravena, Daniel; Ruiz, Eliseo; Hundal, Geeta

    2015-09-28

    Two non-isostructural homometallic 1D neodymium species displaying field-induced slow magnetization relaxations are presented together with theoretical studies. It is established that both systems are better described as organized 1D single molecule magnets (SMMs). Studies show great potential of Nd(III) ions to provide homometallic chains with slow magnetic relaxation.

  4. Lysozyme Crystal

    NASA Technical Reports Server (NTRS)

    2004-01-01

    To the crystallographer, this may not be a diamond but it is just as priceless. A Lysozyme crystal grown in orbit looks great under a microscope, but the real test is X-ray crystallography. The colors are caused by polarizing filters. Proteins can form crystals generated by rows and columns of molecules that form up like soldiers on a parade ground. Shining X-rays through a crystal will produce a pattern of dots that can be decoded to reveal the arrangement of the atoms in the molecules making up the crystal. Like the troops in formation, uniformity and order are everything in X-ray crystallography. X-rays have much shorter wavelengths than visible light, so the best looking crystals under the microscope won't necessarily pass muster under the X-rays. In order to have crystals to use for X-ray diffraction studies, crystals need to be fairly large and well ordered. Scientists also need lots of crystals since exposure to air, the process of X-raying them, and other factors destroy them. Growing protein crystals in space has yielded striking results. Lysozyme's structure is well known and it has become a standard in many crystallization studies on Earth and in space.

  5. Characterization of the fraction components using 1D TOCSY and 1D ROESY experiments. Four new spirostane saponins from Agave brittoniana Trel. spp. Brachypus.

    PubMed

    Macías, Francisco A; Guerra, José O; Simonet, Ana M; Nogueiras, Clara M

    2007-07-01

    A careful NMR analysis, especially 1D TOCSY and 1D ROESY, of two refined saponin fractions allowed us to determine the structures of four new saponins from a polar extract of the Agave brittoniana Trel. spp. Brachypus leaves. A full assignment of the 1H and 13C spectral data for these new saponins, agabrittonosides A-D (1-4), and one previously known saponin, karatavioside A (5) is reported. Their structures were established using a combination of 1D and 2D (1H, 1H-COSY, TOCSY, ROESY, g-HSQC, g-HMBC and g-HSQC-TOCSY) NMR techniques and ESI-MS. Moreover, the work represents a new approach to structural elucidation of saponins in refined fractions by NMR investigations.

  6. Decays B(s)→a1(b1)D(s), a1(b1)D(s)* in the perturbative QCD approach

    NASA Astrophysics Data System (ADS)

    Zhang, Zhi-Qing

    2013-04-01

    Within the framework of the perturbative QCD approach, we study the branching ratios of the two-body charmed decays B(s)→a1(b1)D(s), a1(b1)D(s)*, which, including Cabibbo-Kobayashi-Maskawa, allowed and suppressed decays. Our calculations are consistent with the currently available data and the experimental upper limits. Certainly, many of these predicted channels have not been measured by experiments and can be confronted with the future experimental data. We also discuss the polarization factions of the decays B(s)→a1(b1)D(s)*, some of which are sensitive to the distinct Gegenbauer moments of the wave functions and the decay constants of mesons a1 and b1.

  7. TBC1D1 reduces palmitate oxidation by inhibiting β-HAD activity in skeletal muscle.

    PubMed

    Maher, A C; McFarlan, J; Lally, J; Snook, L A; Bonen, A

    2014-11-01

    In skeletal muscle the Rab-GTPase-activating protein TBC1D1 has been implicated in the regulation of fatty acid oxidation by an unknown mechanism. We determined whether TBC1D1 altered fatty acid utilization via changes in protein-mediated fatty acid transport and/or selected enzymes regulating mitochondrial fatty acid oxidation. We also determined the effects of TBC1D1 on glucose transport and oxidation. Electrotransfection of mouse soleus muscles with TBC1D1 cDNA increased TBC1D1 protein after 2 wk (P<0.05), without altering its paralog AS160. TBC1D1 overexpression decreased basal palmitate oxidation (-22%) while blunting 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR)-stimulated palmitate oxidation (-18%). There was a tendency to increase fatty acid esterification (+10 nmol·g(-1)·60 min(-1), P=0.07), which reflected the reduction in fatty acid oxidation (-12 nmol·g(-1)·60 min(-1)). Concomitantly, basal (+21%) and AICAR-stimulated glucose oxidation (+8%) were increased in TBC1D1-transfected muscles relative to their respective controls (P<0.05), independent of changes in GLUT4 and glucose transport. The reductions in TBC1D1-mediated fatty acid oxidation could not be attributed to changes in the transporter FAT/CD36, muscle mitochondrial content, CPT1 expression or the expression and phosphorylation of AS160, acetyl-CoA carboxylase, or AMPK. However, TBC1D1 overexpression reduced β-HAD enzyme activity (-18%, P<0.05). In conclusion, TBC1D1-mediated reduction of muscle fatty acid oxidation appears to occur via inhibition of β-HAD activity.

  8. RNA Crystallization

    NASA Technical Reports Server (NTRS)

    Golden, Barbara L.; Kundrot, Craig E.

    2003-01-01

    RNA molecules may be crystallized using variations of the methods developed for protein crystallography. As the technology has become available to syntheisize and purify RNA molecules in the quantities and with the quality that is required for crystallography, the field of RNA structure has exploded. The first consideration when crystallizing an RNA is the sequence, which may be varied in a rational way to enhance crystallizability or prevent formation of alternate structures. Once a sequence has been designed, the RNA may be synthesized chemically by solid-state synthesis, or it may be produced enzymatically using RNA polymerase and an appropriate DNA template. Purification of milligram quantities of RNA can be accomplished by HPLC or gel electrophoresis. As with proteins, crystallization of RNA is usually accomplished by vapor diffusion techniques. There are several considerations that are either unique to RNA crystallization or more important for RNA crystallization. Techniques for design, synthesis, purification, and crystallization of RNAs will be reviewed here.

  9. Protein Crystallization

    NASA Technical Reports Server (NTRS)

    Chernov, Alexander A.

    2005-01-01

    Nucleation, growth and perfection of protein crystals will be overviewed along with crystal mechanical properties. The knowledge is based on experiments using optical and force crystals behave similar to inorganic crystals, though with a difference in orders of magnitude in growing parameters. For example, the low incorporation rate of large biomolecules requires up to 100 times larger supersaturation to grow protein, rather than inorganic crystals. Nucleation is often poorly reproducible, partly because of turbulence accompanying the mixing of precipitant with protein solution. Light scattering reveals fluctuations of molecular cluster size, its growth, surface energies and increased clustering as protein ages. Growth most often occurs layer-by-layer resulting in faceted crystals. New molecular layer on crystal face is terminated by a step where molecular incorporation occurs. Quantitative data on the incorporation rate will be discussed. Rounded crystals with molecularly disordered interfaces will be explained. Defects in crystals compromise the x-ray diffraction resolution crucially needed to find the 3D atomic structure of biomolecules. The defects are immobile so that birth defects stay forever. All lattice defects known for inorganics are revealed in protein crystals. Contribution of molecular conformations to lattice disorder is important, but not studied. This contribution may be enhanced by stress field from other defects. Homologous impurities (e.g., dimers, acetylated molecules) are trapped more willingly by a growing crystal than foreign protein impurities. The trapped impurities induce internal stress eliminated in crystals exceeding a critical size (part of mni for ferritin, lysozyme). Lesser impurities are trapped from stagnant, as compared to the flowing, solution. Freezing may induce much more defects unless quickly amorphysizing intracrystalline water.

  10. Computational crystallization.

    PubMed

    Altan, Irem; Charbonneau, Patrick; Snell, Edward H

    2016-07-15

    Crystallization is a key step in macromolecular structure determination by crystallography. While a robust theoretical treatment of the process is available, due to the complexity of the system, the experimental process is still largely one of trial and error. In this article, efforts in the field are discussed together with a theoretical underpinning using a solubility phase diagram. Prior knowledge has been used to develop tools that computationally predict the crystallization outcome and define mutational approaches that enhance the likelihood of crystallization. For the most part these tools are based on binary outcomes (crystal or no crystal), and the full information contained in an assembly of crystallization screening experiments is lost. The potential of this additional information is illustrated by examples where new biological knowledge can be obtained and where a target can be sub-categorized to predict which class of reagents provides the crystallization driving force. Computational analysis of crystallization requires complete and correctly formatted data. While massive crystallization screening efforts are under way, the data available from many of these studies are sparse. The potential for this data and the steps needed to realize this potential are discussed.

  11. Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR

    PubMed Central

    Shoshan, Michal S.; Tshuva, Edit Y.; Shalev, Deborah E.

    2013-01-01

    Copper (I) binding by metallochaperone transport proteins prevents copper oxidation and release of the toxic ions that may participate in harmful redox reactions. The Cu (I) complex of the peptide model of a Cu (I) binding metallochaperone protein, which includes the sequence MTCSGCSRPG (underlined is conserved), was determined in solution under inert conditions by NMR spectroscopy. NMR is a widely accepted technique for the determination of solution structures of proteins and peptides. Due to difficulty in crystallization to provide single crystals suitable for X-ray crystallography, the NMR technique is extremely valuable, especially as it provides information on the solution state rather than the solid state. Herein we describe all steps that are required for full three-dimensional structure determinations by NMR. The protocol includes sample preparation in an NMR tube, 1D and 2D data collection and processing, peak assignment and integration, molecular mechanics calculations, and structure analysis. Importantly, the analysis was first conducted without any preset metal-ligand bonds, to assure a reliable structure determination in an unbiased manner. PMID:24378924

  12. New Mononuclear Cu(II) Complexes and 1D Chains with 4-Amino-4H-1,2,4-triazole

    PubMed Central

    Dîrtu, Marinela M.; Boland, Yves; Gillard, Damien; Tinant, Bernard; Robeyns, Koen; Safin, Damir A.; Devlin, Eamonn; Sanakis, Yiannis; Garcia, Yann

    2013-01-01

    The crystal structures of two mononuclear Cu(II) NH2trz complexes [Cu(NH2trz)4(H2O)](AsF6)2 (I) and [Cu(NH2trz)4(H2O)](PF6)2 (II) as well as two coordination polymers [Cu(μ2-NH2trz)2Cl]Cl·H2O (III) and [Cu(μ2-NH2trz)2Cl] (SiF6)0.5·1.5H2O (IV) are presented. Cationic 1D chains with bridging bis-monodentate μ2-coordinated NH2trz and bridging μ2-coordinated chloride ligands are present in III and IV. In these coordination polymers, the Cu(II) ions are strongly antiferromagnetically coupled with J = −128.4 cm−1 for III and J = −143 cm−1 for IV (H = −J∑SiSi+1), due to the nature of the bridges between spin centers. Inter-chain interactions present in the crystal structures were taken into consideration, as well as g factors, which were determined experimentally, for the quantitative modeling of their magnetic properties. PMID:24300095

  13. Mycobacterial phosphatidylinositol mannoside is a natural antigen for CD1d-restricted T cells

    PubMed Central

    Fischer, Karsten; Scotet, Emmanuel; Niemeyer, Marcus; Koebernick, Heidrun; Zerrahn, Jens; Maillet, Sophie; Hurwitz, Robert; Kursar, Mischo; Bonneville, Marc; Kaufmann, Stefan H. E.; Schaible, Ulrich E.

    2004-01-01

    A group of T cells recognizes glycolipids presented by molecules of the CD1 family. The CD1d-restricted natural killer T cells (NKT cells) are primarily considered to be self-reactive. By employing CD1d-binding and T cell assays, the following structural parameters for presentation by CD1d were defined for a number of mycobacterial and mammalian lipids: two acyl chains facilitated binding, and a polar head group was essential for T cell recognition. Of the mycobacterial lipids tested, only a phosphatidylinositol mannoside (PIM) fulfilled the requirements for CD1d binding and NKT cell stimulation. This PIM activated human and murine NKT cells via CD1d, thereby triggering antigen-specific IFN-γ production and cell-mediated cytotoxicity, and PIM-loaded CD1d tetramers identified a subpopulation of murine and human NKT cells. This phospholipid, therefore, represents a mycobacterial antigen recognized by T cells in the context of CD1d. PMID:15243159

  14. Structure and Catalytic Mechanism of Human Steroid 5-Reductase (AKR1D1)

    SciTech Connect

    Costanzo, L.; Drury, J; Christianson, D; Penning, T

    2009-01-01

    Human steroid 5{beta}-reductase (aldo-keto reductase (AKR) 1D1) catalyzes reduction of {Delta}{sup 4}-ene double bonds in steroid hormones and bile acid precursors. We have reported the structures of an AKR1D1-NADP{sup +} binary complex, and AKR1D1-NADP{sup +}-cortisone, AKR1D1-NADP{sup +}-progesterone and AKR1D1-NADP{sup +}-testosterone ternary complexes at high resolutions. Recently, structures of AKR1D1-NADP{sup +}-5{beta}-dihydroprogesterone complexes showed that the product is bound unproductively. Two quite different mechanisms of steroid double bond reduction have since been proposed. However, site-directed mutagenesis supports only one mechanism. In this mechanism, the 4-pro-R hydride is transferred from the re-face of the nicotinamide ring to C5 of the steroid substrate. E120, a unique substitution in the AKR catalytic tetrad, permits a deeper penetration of the steroid substrate into the active site to promote optimal reactant positioning. It participates with Y58 to create a 'superacidic' oxyanion hole for polarization of the C3 ketone. A role for K87 in the proton relay proposed using the AKR1D1-NADP{sup +}-5{beta}-dihydroprogesterone structure is not supported.

  15. TBC1D14 regulates autophagy via the TRAPP complex and ATG9 traffic.

    PubMed

    Lamb, Christopher A; Nühlen, Stefanie; Judith, Delphine; Frith, David; Snijders, Ambrosius P; Behrends, Christian; Tooze, Sharon A

    2016-02-01

    Macroautophagy requires membrane trafficking and remodelling to form the autophagosome and deliver its contents to lysosomes for degradation. We have previously identified the TBC domain-containing protein, TBC1D14, as a negative regulator of autophagy that controls delivery of membranes from RAB11-positive recycling endosomes to forming autophagosomes. In this study, we identify the TRAPP complex, a multi-subunit tethering complex and GEF for RAB1, as an interactor of TBC1D14. TBC1D14 binds to the TRAPP complex via an N-terminal 103 amino acid region, and overexpression of this region inhibits both autophagy and secretory traffic. TRAPPC8, the mammalian orthologue of a yeast autophagy-specific TRAPP subunit, forms part of a mammalian TRAPPIII-like complex and both this complex and TBC1D14 are needed for RAB1 activation. TRAPPC8 modulates autophagy and secretory trafficking and is required for TBC1D14 to bind TRAPPIII. Importantly, TBC1D14 and TRAPPIII regulate ATG9 trafficking independently of ULK1. We propose a model whereby TBC1D14 and TRAPPIII regulate a constitutive trafficking step from peripheral recycling endosomes to the early Golgi, maintaining the cycling pool of ATG9 required for initiation of autophagy. PMID:26711178

  16. Role and regulation of CD1d in normal and pathological B cells

    PubMed Central

    Chaudhry, Mohammed S.; Karadimitris, Anastasios

    2015-01-01

    CD1d is a non-polymorphic, MHC class I-like molecule, which presents phosphoand glycosphingo-lipid antigens to a subset of CD1d-restricted T cells called invariant NKT (iNKT) cells. This CD1d-iNKT cell axis regulates nearly all aspects of both the innate and adaptive immune response. Expression of CD1d on B cells is suggestive of the ability of these cells to present antigen to and form cognate interactions with iNKT cells. Herein we summarise key evidence regarding the role and regulation of CD1d in normal B cells and in humoral immunity. We then extend the discussion to B cell disorders, with emphasis on autoimmune disease, viral infection and neoplastic transformation of B lineage cells, where CD1d expression can be altered as a mechanism of immune evasion, and can have both diagnostic and prognostic importance. Finally we highlight current and future therapeutic strategies that aim to target the CD1d-iNKT axis in B cells. PMID:25381357

  17. Calreticulin Controls the Rate of Assembly of CD1d Molecules in the Endoplasmic Reticulum*

    PubMed Central

    Zhu, Yajuan; Zhang, Wei; Veerapen, Natacha; Besra, Gurdyal; Cresswell, Peter

    2010-01-01

    CD1d is an MHC class I-like molecule comprised of a transmembrane glycoprotein (heavy chain) associated with β2-microglobulin (β2m) that presents lipid antigens to NKT cells. Initial folding of the heavy chain involves its glycan-dependent association with calreticulin (CRT), calnexin (CNX), and the thiol oxidoreductase ERp57, and is followed by assembly with β2m to form the heterodimer. Here we show that in CRT-deficient cells CD1d heavy chains convert to β2m-associated dimers at an accelerated rate, indicating faster folding of the heavy chain, while the rate of intracellular transport after assembly is unaffected. Unlike the situation with MHC class I molecules, antigen presentation by CD1d is not impaired in the absence of CRT. Instead, there are elevated levels of stable and functional CD1d on the surface of CRT-deficient cells. Association of the heavy chains with the ER chaperones Grp94 and Bip is observed in the absence of CRT, and these may replace CRT in mediating CD1d folding and assembly. ER retention of free CD1d heavy chains is impaired in CRT-deficient cells, allowing their escape and subsequent expression on the plasma membrane. However, these free heavy chains are rapidly internalized and degraded in lysosomes, indicating that β2m association is required for the exceptional resistance of CD1d to lysosomal degradation that is normally observed. PMID:20861015

  18. The FC-1D: The profitable alternative Flying Circus Commercial Aviation Group

    NASA Technical Reports Server (NTRS)

    Meza, Victor J.; Alvarez, Jaime; Harrington, Brook; Lujan, Michael A.; Mitlyng, David; Saroughian, Andy; Silva, Alex; Teale, Tim

    1994-01-01

    The FC-1D was designed as an advanced solution for a low cost commercial transport meeting or exceeding all of the 1993/1994 AIAA/Lockheed request for proposal requirements. The driving philosophy behind the design of the FC-1D was the reduction of airline direct operating costs. Every effort was made during the design process to have the customer in mind. The Flying Circus Commercial Aviation Group targeted reductions in drag, fuel consumption, manufacturing costs, and maintenance costs. Flying Circus emphasized cost reduction throughout the entire design program. Drag reduction was achieved by implementation of the aft nacelle wing configuration to reduce cruise drag and increase cruise speeds. To reduce induced drag, rather than increasing the wing span of the FC-1D, spiroids were included in the efficient wing design. Profile and friction drag are reduced by using riblets in place of paint around the fuselage and empennage of the FC-1D. Choosing a single aisle configuration enabled the Flying Circus to optimize the fuselage diameter. Thus, reducing fuselage drag while gaining high structural efficiency. To further reduce fuel consumption a weight reduction program was conducted through the use of composite materials. An additional quality of the FC-1D is its design for low cost manufacturing and assembly. As a result of this design attribute, the FC-1D will have fewer parts which reduces weight as well as maintenance and assembly costs. The FC-1D is affordable and effective, the apex of commercial transport design.

  19. On the current drive capability of low dimensional semiconductors: 1D versus 2D

    DOE PAGES

    Zhu, Y.; Appenzeller, J.

    2015-10-29

    Low-dimensional electronic systems are at the heart of many scaling approaches currently pursuit for electronic applications. Here, we present a comparative study between an array of one-dimensional (1D) channels and its two-dimensional (2D) counterpart in terms of current drive capability. Lastly, our findings from analytical expressions derived in this article reveal that under certain conditions an array of 1D channels can outperform a 2D field-effect transistor because of the added degree of freedom to adjust the threshold voltage in an array of 1D devices.

  20. TCTEX1D2 mutations underlie Jeune asphyxiating thoracic dystrophy with impaired retrograde intraflagellar transport.

    PubMed

    Schmidts, Miriam; Hou, Yuqing; Cortés, Claudio R; Mans, Dorus A; Huber, Celine; Boldt, Karsten; Patel, Mitali; van Reeuwijk, Jeroen; Plaza, Jean-Marc; van Beersum, Sylvia E C; Yap, Zhi Min; Letteboer, Stef J F; Taylor, S Paige; Herridge, Warren; Johnson, Colin A; Scambler, Peter J; Ueffing, Marius; Kayserili, Hulya; Krakow, Deborah; King, Stephen M; Beales, Philip L; Al-Gazali, Lihadh; Wicking, Carol; Cormier-Daire, Valerie; Roepman, Ronald; Mitchison, Hannah M; Witman, George B

    2015-01-01

    The analysis of individuals with ciliary chondrodysplasias can shed light on sensitive mechanisms controlling ciliogenesis and cell signalling that are essential to embryonic development and survival. Here we identify TCTEX1D2 mutations causing Jeune asphyxiating thoracic dystrophy with partially penetrant inheritance. Loss of TCTEX1D2 impairs retrograde intraflagellar transport (IFT) in humans and the protist Chlamydomonas, accompanied by destabilization of the retrograde IFT dynein motor. We thus define TCTEX1D2 as an integral component of the evolutionarily conserved retrograde IFT machinery. In complex with several IFT dynein light chains, it is required for correct vertebrate skeletal formation but may be functionally redundant under certain conditions. PMID:26044572

  1. TCTEX1D2 mutations underlie Jeune asphyxiating thoracic dystrophy with impaired retrograde intraflagellar transport

    PubMed Central

    Schmidts, Miriam; Hou, Yuqing; Cortés, Claudio R.; Mans, Dorus A.; Huber, Celine; Boldt, Karsten; Patel, Mitali; van Reeuwijk, Jeroen; Plaza, Jean-Marc; van Beersum, Sylvia E. C.; Yap, Zhi Min; Letteboer, Stef J. F.; Taylor, S. Paige; Herridge, Warren; Johnson, Colin A.; Scambler, Peter J.; Ueffing, Marius; Kayserili, Hulya; Krakow, Deborah; King, Stephen M.; Beales, Philip L.; Al-Gazali, Lihadh; Wicking, Carol; Cormier-Daire, Valerie; Roepman, Ronald; Mitchison, Hannah M.; Witman, George B.; Al-Turki, Saeed; Anderson, Carl; Anney, Richard; Antony, Dinu; Asimit, Jennifer; Ayub, Mohammad; Barrett, Jeff; Barroso, Inês; Bentham, Jamie; Bhattacharya, Shoumo; Blackwood, Douglas; Bobrow, Martin; Bochukova, Elena; Bolton, Patrick; Boustred, Chris; Breen, Gerome; Brion, Marie-Jo; Brown, Andrew; Calissano, Mattia; Carss, Keren; Chatterjee, Krishna; Chen, Lu; Cirak, Sebhattin; Clapham, Peter; Clement, Gail; Coates, Guy; Collier, David; Cosgrove, Catherine; Cox, Tony; Craddock, Nick; Crooks, Lucy; Curran, Sarah; Daly, Allan; Danecek, Petr; Smith, George Davey; Day-Williams, Aaron; Day, Ian; Durbin, Richard; Edkins, Sarah; Ellis, Peter; Evans, David; Farooqi, I. Sadaf; Fatemifar, Ghazaleh; Fitzpatrick, David; Flicek, Paul; Floyd, Jamie; Foley, A. Reghan; Franklin, Chris; Futema, Marta; Gallagher, Louise; Gaunt, Tom; Geschwind, Daniel; Greenwood, Celia; Grozeva, Detelina; Guo, Xiaosen; Gurling, Hugh; Hart, Deborah; Hendricks, Audrey; Holmans, Peter; Huang, Jie; Humphries, Steve E.; Hurles, Matt; Hysi, Pirro; Jackson, David; Jamshidi, Yalda; Jewell, David; Chris, Joyce; Kaye, Jane; Keane, Thomas; Kemp, John; Kennedy, Karen; Kent, Alastair; Kolb-Kokocinski, Anja; Lachance, Genevieve; Langford, Cordelia; Lee, Irene; Li, Rui; Li, Yingrui; Ryan, Liu; Lönnqvist, Jouko; Lopes, Margarida; MacArthur, Daniel G.; Massimo, Mangino; Marchini, Jonathan; Maslen, John; McCarthy, Shane; McGuffin, Peter; McIntosh, Andrew; McKechanie, Andrew; McQuillin, Andrew; Memari, Yasin; Metrustry, Sarah; Min, Josine; Moayyeri, Alireza; Morris, James; Muddyman, Dawn; Muntoni, Francesco; Northstone, Kate; O'Donovan, Michael; O'Rahilly, Stephen; Onoufriadis, Alexandros; Oualkacha, Karim; Owen, Michael; Palotie, Aarno; Panoutsopoulou, Kalliope; Parker, Victoria; Parr, Jeremy; Paternoster, Lavinia; Paunio, Tiina; Payne, Felicity; Perry, John; Pietilainen, Olli; Plagnol, Vincent; Quail, Michael A.; Quaye, Lydia; Raymond, Lucy; Rehnström, Karola; Brent Richards, J.; Ring, Sue; Ritchie, Graham R S; Savage, David B.; Schoenmakers, Nadia; Semple, Robert K.; Serra, Eva; Shihab, Hashem; Shin, So-Youn; Skuse, David; Small, Kerrin; Smee, Carol; Soler, Artigas María; Soranzo, Nicole; Southam, Lorraine; Spector, Tim; St Pourcain, Beate; St. Clair, David; Stalker, Jim; Surdulescu, Gabriela; Suvisaari, Jaana; Tachmazidou, Ioanna; Tian, Jing; Timpson, Nic; Tobin, Martin; Valdes, Ana; van Kogelenberg, Margriet; Vijayarangakannan, Parthiban; Wain, Louise; Walter, Klaudia; Wang, Jun; Ward, Kirsten; Wheeler, Ellie; Whittall, Ros; Williams, Hywel; Williamson, Kathy; Wilson, Scott G.; Wong, Kim; Whyte, Tamieka; ChangJiang, Xu; Zeggini, Eleftheria; Zhang, Feng; Zheng, Hou-Feng

    2015-01-01

    The analysis of individuals with ciliary chondrodysplasias can shed light on sensitive mechanisms controlling ciliogenesis and cell signalling that are essential to embryonic development and survival. Here we identify TCTEX1D2 mutations causing Jeune asphyxiating thoracic dystrophy with partially penetrant inheritance. Loss of TCTEX1D2 impairs retrograde intraflagellar transport (IFT) in humans and the protist Chlamydomonas, accompanied by destabilization of the retrograde IFT dynein motor. We thus define TCTEX1D2 as an integral component of the evolutionarily conserved retrograde IFT machinery. In complex with several IFT dynein light chains, it is required for correct vertebrate skeletal formation but may be functionally redundant under certain conditions. PMID:26044572

  2. Comet Halley O(1D) and H2O production rates

    NASA Technical Reports Server (NTRS)

    Magee-Sauer, K.; Scherb, F.; Roesler, F. L.; Harlander, J.

    1990-01-01

    Ground-based dual-etalon Fabry-Perot spectrometer observations have been made of Comet Halley's forbidden O I 6300 A emission. The 0.2 A resolution of the spectral scans was sufficient to resolve the O I forbidden line emissions from both nearby cometary NH2 and telluric emissions. On the basis of these measurements, the production rate Q of O(1D) was determined; it is then found, by taking into account the photodissociation of H2O and OH as sources of O(1D), that the ratio of H2O/O(1D) production rates is of the order of 6.

  3. On the Current Drive Capability of Low Dimensional Semiconductors: 1D versus 2D.

    PubMed

    Zhu, Y; Appenzeller, J

    2015-12-01

    Low-dimensional electronic systems are at the heart of many scaling approaches currently pursuit for electronic applications. Here, we present a comparative study between an array of one-dimensional (1D) channels and its two-dimensional (2D) counterpart in terms of current drive capability. Our findings from analytical expressions derived in this article reveal that under certain conditions an array of 1D channels can outperform a 2D field-effect transistor because of the added degree of freedom to adjust the threshold voltage in an array of 1D devices.

  4. Crystal Data

    National Institute of Standards and Technology Data Gateway

    SRD 3 NIST Crystal Data (PC database for purchase)   NIST Crystal Data contains chemical, physical, and crystallographic information useful to characterize more than 237,671 inorganic and organic crystalline materials. The data include the standard cell parameters, cell volume, space group number and symbol, calculated density, chemical formula, chemical name, and classification by chemical type.

  5. Novel hollow mesoporous 1D TiO2 nanofibers as photovoltaic and photocatalytic materials.

    PubMed

    Zhang, Xiang; Thavasi, Velmurugan; Mhaisalkar, S G; Ramakrishna, Seeram

    2012-03-01

    Hollow mesoporous one dimensional (1D) TiO(2) nanofibers are successfully prepared by co-axial electrospinning of a titanium tetraisopropoxide (TTIP) solution with two immiscible polymers; polyethylene oxide (PEO) and polyvinylpyrrolidone (PVP) using a core-shell spinneret, followed by annealing at 450 °C. The annealed mesoporous TiO(2) nanofibers are found to having a hollow structure with an average diameter of 130 nm. Measurements using the Brunauer-Emmett-Teller (BET) method reveal that hollow mesoporous TiO(2) nanofibers possess a high surface area of 118 m(2) g(-1) with two types of mesopores; 3.2 nm and 5.4 nm that resulted from gaseous removal of PEO and PVP respectively during annealing. With hollow mesoporous TiO(2) nanofibers as the photoelectrode in dye sensitized solar cells (DSSC), the solar-to-current conversion efficiency (η) and short circuit current (J(sc)) are measured as 5.6% and 10.38 mA cm(-2) respectively, which are higher than those of DSSC made using regular TiO(2) nanofibers under identical conditions (η = 4.2%, J(sc) = 8.99 mA cm(-2)). The improvement in the conversion efficiency is mainly attributed to the higher surface area and mesoporous TiO(2) nanostructure. It facilitates the adsorption of more dye molecules and also promotes the incident photon to electron conversion. Hollow mesoporous TiO(2) nanofibers with close packing of grains and crystals intergrown with each other demonstrate faster electron diffusion, and longer electron recombination time than regular TiO(2) nanofibers as well as P25 nanoparticles. The surface effect of hollow mesoporous TiO(2) nanofibers as a photocatalyst for the degradation of rhodamine dye was also investigated. The kinetic study shows that the hollow mesoporous surface of the TiO(2) nanofibers influenced its interactions with the dye, and resulted in an increased catalytic activity over P25 TiO(2) nanocatalysts. PMID:22315140

  6. Photonic crystal technology for terahertz system integration

    NASA Astrophysics Data System (ADS)

    Fujita, Masayuki; Nagatsuma, Tadao

    2016-04-01

    Developing terahertz integration technology is essential for practical use of terahertz electromagnetic waves (0.1-10 THz) in various applications including broadband wireless communication, spectroscopic sensing, and nondestructive imaging. In this paper, we present our recent challenges towards terahertz system integration based on photonic crystal technology such as the development of terahertz transceivers. We use photonic-crystal slabs consisting of a twodimensional lattice of air holes formed in a silicon slab to develop low loss compact terahertz components in planar structures. The demonstration of ultralow loss (< 0.1 dB/cm) waveguides and integrated transceiver devices in the 0.3 THz band shows the potential for the application of photonic crystals to terahertz integration technology. Improving the coupling efficiency between the photonic crystal waveguide and resonant tunneling diode is important to take full advantage of the ultralow loss photonic crystal waveguides.

  7. Ubiquitination and degradation of the hominoid-specific oncoprotein TBC1D3 is regulated by protein palmitoylation

    SciTech Connect

    Kong, Chen; Lange, Jeffrey J.; Samovski, Dmitri; Su, Xiong; Liu, Jialiu; Sundaresan, Sinju; Stahl, Philip D.

    2013-05-03

    Highlights: •Hominoid-specific oncogene TBC1D3 is targeted to plasma membrane by palmitoylation. •TBC1D3 is palmitoylated on two cysteine residues: 318 and 325. •TBC1D3 palmitoylation governs growth factors-induced TBC1D3 degradation. •Post-translational modifications may regulate oncogenic properties of TBC1D3. -- Abstract: Expression of the hominoid-specific oncoprotein TBC1D3 promotes enhanced cell growth and proliferation by increased activation of signal transduction through several growth factors. Recently we documented the role of CUL7 E3 ligase in growth factors-induced ubiquitination and degradation of TBC1D3. Here we expanded our study to discover additional molecular mechanisms that control TBC1D3 protein turnover. We report that TBC1D3 is palmitoylated on two cysteine residues: 318 and 325. The expression of double palmitoylation mutant TBC1D3:C318/325S resulted in protein mislocalization and enhanced growth factors-induced TBC1D3 degradation. Moreover, ubiquitination of TBC1D3 via CUL7 E3 ligase complex was increased by mutating the palmitoylation sites, suggesting that depalmitoylation of TBC1D3 makes the protein more available for ubiquitination and degradation. The results reported here provide novel insights into the molecular mechanisms that govern TBC1D3 protein degradation. Dysregulation of these mechanisms in vivo could potentially result in aberrant TBC1D3 expression and promote oncogenesis.

  8. Pseudo 1-D Micro/Nanofluidic Device for Exact Electrokinetic Responses.

    PubMed

    Kim, Junsuk; Kim, Ho-Young; Lee, Hyomin; Kim, Sung Jae

    2016-06-28

    Conventionally, a 1-D micro/nanofluidic device, whose nanochannel bridged two microchannels, was widely chosen in the fundamental electrokinetic studies; however, the configuration had intrinsic limitations of the time-consuming and labor intensive tasks of filling and flushing the microchannel due to the high fluidic resistance of the nanochannel bridge. In this work, a pseudo 1-D micro/nanofluidic device incorporating air valves at each microchannel was proposed for mitigating these limitations. High Laplace pressure formed at liquid/air interface inside the microchannels played as a virtual valve only when the electrokinetic operations were conducted. The identical electrokinetic behaviors of the propagation of ion concentration polarization layer and current-voltage responses were obtained in comparison with the conventional 1-D micro/nanofluidic device by both experiments and numerical simulations. Therefore, the suggested pseudo 1-D micro/nanofluidic device owned not only experimental conveniences but also exact electrokinetic responses. PMID:27248856

  9. Quantum and semi-classical transport in RTDs using NEMO 1-D

    NASA Technical Reports Server (NTRS)

    Klimeck, G.; Stout, P.; Bowen, R. C.

    2003-01-01

    NEMO 1-D has been developed primarily for the simulation of resonant tunneling diodes, and quantitative and predictive agreements with experimental high performance, high current density devices have been achieved in the past.

  10. Novel electronic structures of self-organized 1D surface nanostructures

    NASA Astrophysics Data System (ADS)

    Yeom, Han Woong

    2002-03-01

    Recently we have searched for the exotic physical properties of the nanostructures formed on semiconductor surfaces by STM and photoelectron spectroscopy [1]. The major objects have been the 1D chains of metal adsorbates on Si or SiC surfaces. It now seems obvious that such (sub)nanometer-scale atomic chains possess significant technological implications for the future device technology. Furthermore those systems provide very attractive and unprecedented opportunity to study exotic physical properties of 1D electronic systems in detail, such as Peierls instability, charge density wave (CDW), electron correlation, non-Fermi liquid behavior, and interplay of defects with 1D excitations (1D solitons, 1D domain walls and etc). The present talk focuses on the recent experimental and theoretical studies for the novel electronic properties of the 1D atomic chain systems on the Si(111) surface such as Si(111)4x1-In [2], Si(111)5x2-Au [3], Si(557)5x2-Au [4], and Si(111)3x2-Ba(or Ca) [5]. These systems have well defined one dimensional electronic bands, which exhibit intriguing properties challenging our present understanding. The major points of debates right now are the origin of the periodicity-doubling phase transition of Si(111)4x1-In in relation to 1D CDW [2], the nature of the band gap (or pseudo gap) of Si(111)5x2-Au (also related to 1D CDW idea) [3], the Si(111)3x2-Ba (or Ca) surface (1D Mott-Hubbard system ?) [5], and the nature of the band dispersion of the Si(557)5x2-Au surface (any Luttinger liquid behavior ?) [4]. Some new aspects of these systems are introduced such as the doping dependence of the 1D CDW system and the transport measurements across the 1D CDW transition. References [1] For a recent review, see H. W. Yeom, J. Electron Spectro. and Rel. Phenom., 114-116, 283 (2001). [2] H.W. Yeom et al., Phys. Rev. Lett. 82, 4898 (1999); C. Kumpf et al, Phys. Rev. Lett. 85, 4916 (2001); H.W. Yeom et al., submitted; G. Le Lay et al., submitted; J.-H. Cho et al

  11. Alkali concentration-dependent tailoring of highly controllable titanate nanostructures: From yolk-shell, hollow 3D nanospheres to 1D nanowires

    NASA Astrophysics Data System (ADS)

    Qi, Yue; Luan, Yi; Yang, Mu; Wang, Ge; Tan, Li; Li, Jie

    2014-02-01

    We demonstrate a facile strategy to access 0D nanoparticles to 3D hierarchical structures through a hydrothermal process. The morphology of the products is alkali concentration-dependent, which was systematically investigated. As the NaOH concentration rising, morphology transformations from yolk-shell, hollow hierarchical 3D nanospheres to 1D nanowires are achieved. The crystal phase, the transformation relationship, and the formation mechanisms were studied as well. Furthermore, TiO2 with diversified morphologies was evaluated as styrene oxidation catalyst and showed excellent catalytic activities and chemical stability.

  12. Actinometric measurement of j(O3-O(1D)) using a luminol detector

    NASA Technical Reports Server (NTRS)

    Bairai, Solomon T.; Stedman, Donald H.

    1992-01-01

    The photolysis frequency of ozone to singlet D oxygen atoms has been measured by means of a chemical actinometer using a luminol based detector. The instrument measures j(O3-O(1D)) with a precision of 10 percent. The data collected in winter and spring of 1991 is in agreement with model predictions and previously measured values. Data from a global solar radiometer can be used to estimate the effects of local cloudiness on j(O3-O(1D)).

  13. Coherent Synchrotron Radiation and Space Charge for a 1-D Bunch on an Arbitrary Planar Orbit

    SciTech Connect

    Warnock, R.L.; /SLAC

    2008-01-08

    Realistic modeling of coherent synchrotron radiation (CSR) and the space charge force in single-pass systems and rings usually requires at least a two-dimensional (2-D) description of the charge/current density of the bunch. Since that leads to costly computations, one often resorts to a 1-D model of the bunch for first explorations. This paper provides several improvements to previous 1-D theories, eliminating unnecessary approximations and physical restrictions.

  14. NR1D1 ameliorates Mycobacterium tuberculosis clearance through regulation of autophagy

    PubMed Central

    Chandra, Vemika; Bhagyaraj, Ella; Nanduri, Ravikanth; Ahuja, Nancy; Gupta, Pawan

    2015-01-01

    NR1D1 (nuclear receptor subfamily 1, group D, member 1), an adopted orphan nuclear receptor, is widely known to orchestrate the expression of genes involved in various biological processes such as adipogenesis, skeletal muscle differentiation, and lipid and glucose metabolism. Emerging evidence suggests that various members of the nuclear receptor superfamily perform a decisive role in the modulation of autophagy. Recently, NR1D1 has been implicated in augmenting the antimycobacterial properties of macrophages and providing protection against Mycobacterium tuberculosis infection by downregulating the expression of the IL10 gene in human macrophages. This antiinfective property of NR1D1 suggests the need for an improved understanding of its role in other host-associated antimycobacterial pathways. The results presented here demonstrate that in human macrophages either ectopic expression of NR1D1 or treatment with its agonist, GSK4112, enhanced the number of acidic vacuoles as well as the level of MAP1LC3-II, a signature molecule for determination of autophagy progression, in a concentration- and time-dependent manner. Conversely, a decrease in NR1D1 in knockdown cells resulted in the reduced expression of lysosomal-associated membrane protein 1, LAMP1, commensurate with a decrease in the level of transcription factor EB, TFEB. This is indicative of that NR1D1 may have a regulatory role in lysosome biogenesis. NR1D1 being a repressor, its positive regulation on LAMP1 and TFEB is suggestive of an indirect byzantine mechanism of action. Its role in the modulation of autophagy and lysosome biogenesis together with its ability to repress IL10 gene expression supports the theory that NR1D1 has a pivotal antimycobacterial function in human macrophages. PMID:26390081

  15. PPM1D controls nucleolar formation by up-regulating phosphorylation of nucleophosmin.

    PubMed

    Kozakai, Yuuki; Kamada, Rui; Furuta, Junya; Kiyota, Yuhei; Chuman, Yoshiro; Sakaguchi, Kazuyasu

    2016-01-01

    An increase of nucleolar number and size has made nucleoli essential markers for cytology and tumour development. However, the underlying basis for their structural integrity and abundance remains unclear. Protein phosphatase PPM1D was found to be up-regulated in different carcinomas including breast cancers. Here, we demonstrate for the first time that PPM1D regulates nucleolar formation via inducing an increased phosphorylation of the nucleolar protein NPM. We show that PPM1D overexpression induces an increase in the nucleolar number regardless of p53 status. We also demonstrated that specific sequential phosphorylation of NPM is important for nucleolar formation and that PPM1D is a novel upstream regulator of this phosphorylation pathway. These results enhance our understanding of the molecular mechanisms that govern nucleoli formation by demonstrating that PPM1D regulates nucleolar formation by regulating NPM phosphorylation status through a novel signalling pathway, PPM1D-CDC25C-CDK1-PLK1. PMID:27619510

  16. Epigenetic activation of a cryptic TBC1D16 transcript enhances melanoma progression by targeting EGFR

    PubMed Central

    Vizoso, Miguel; Ferreira, Humberto J; Lopez-Serra, Paula; Javier Carmona, F; Martínez-Cardús, Anna; Girotti, Maria Romina; Villanueva, Alberto; Guil, Sonia; Moutinho, Catia; Liz, Julia; Portela, Anna; Heyn, Holger; Moran, Sebastian; Vidal, August; Martinez-Iniesta, Maria; Manzano, Jose L; Fernandez-Figueras, Maria Teresa; Elez, Elena; Muñoz-Couselo, Eva; Botella-Estrada, Rafael; Berrocal, Alfonso; Pontén, Fredrik; van den Oord, Joost; Gallagher, William M; Frederick, Dennie T; Flaherty, Keith T; McDermott, Ultan; Lorigan, Paul; Marais, Richard; Esteller, Manel

    2016-01-01

    Metastasis is responsible for most cancer-related deaths, and, among common tumor types, melanoma is one with great potential to metastasize. Here we study the contribution of epigenetic changes to the dissemination process by analyzing the changes that occur at the DNA methylation level between primary cancer cells and metastases. We found a hypomethylation event that reactivates a cryptic transcript of the Rab GTPase activating protein TBC1D16 (TBC1D16-47 kDa; referred to hereafter as TBC1D16-47KD) to be a characteristic feature of the metastatic cascade. This short isoform of TBC1D16 exacerbates melanoma growth and metastasis both in vitro and in vivo. By combining immunoprecipitation and mass spectrometry, we identified RAB5C as a new TBC1D16 target and showed that it regulates EGFR in melanoma cells. We also found that epigenetic reactivation of TBC1D16-47KD is associated with poor clinical outcome in melanoma, while conferring greater sensitivity to BRAF and MEK inhibitors. PMID:26030178

  17. PPM1D controls nucleolar formation by up-regulating phosphorylation of nucleophosmin

    PubMed Central

    Kozakai, Yuuki; Kamada, Rui; Furuta, Junya; Kiyota, Yuhei; Chuman, Yoshiro; Sakaguchi, Kazuyasu

    2016-01-01

    An increase of nucleolar number and size has made nucleoli essential markers for cytology and tumour development. However, the underlying basis for their structural integrity and abundance remains unclear. Protein phosphatase PPM1D was found to be up-regulated in different carcinomas including breast cancers. Here, we demonstrate for the first time that PPM1D regulates nucleolar formation via inducing an increased phosphorylation of the nucleolar protein NPM. We show that PPM1D overexpression induces an increase in the nucleolar number regardless of p53 status. We also demonstrated that specific sequential phosphorylation of NPM is important for nucleolar formation and that PPM1D is a novel upstream regulator of this phosphorylation pathway. These results enhance our understanding of the molecular mechanisms that govern nucleoli formation by demonstrating that PPM1D regulates nucleolar formation by regulating NPM phosphorylation status through a novel signalling pathway, PPM1D-CDC25C-CDK1-PLK1. PMID:27619510

  18. The Role of O(1D) in the Oxidation of Si(100)

    SciTech Connect

    Kaspar, Tiffany C. ); Tuan, Allan C. ); Tonkyn, Russell G. ); Hess, Wayne P. ); Rogers, Jr., J. W.; Ono, Yoshi

    2003-03-20

    Oxidation of silicon with neutral atomic oxygen species generated in a rare gas plasma has recently been shown to produce high-quality thin oxides. It has been speculated that atomic oxygen in the first excited state, O(1D), is a dominant reactive species in the oxidation mechanism. In this study, we investigate the role of O(1D) in silicon oxidation in the absence of other oxidizing species. The O(1D) is generated by laser-induced photodissociation of N2O at 193 nm. We find that, at 400?C, O(1D) is effective in the initial stages of oxidation, but the oxide growth rate falls dramatically past 1.5 nm. Oxide films thicker than 2 nm were unachievable regardless of oxidation time or N2O partial pressure (0.5-90 mTorr), indicating O(1D) cannot be a dominant reactive species in thicker oxidation mechanisms. We suggest that quenching of O(1D) to O(3P) (ground state) during diffusion through thicker oxides results in drastically slower oxidation kinetics. In contrast, oxidation with a vacuum ultraviolet (VUV) excimer lamp operating at 172 nm resulted in oxide thicknesses up to 4 nm. Thus, other species produced in plasmas and excimer lamps, such as molecular and atomic ions, photons, and free and conduction band electrons, play a dominant role in the rapid oxidation mechanism of thicker oxides (> 2 nm).

  19. Epigenetic activation of a cryptic TBC1D16 transcript enhances melanoma progression by targeting EGFR.

    PubMed

    Vizoso, Miguel; Ferreira, Humberto J; Lopez-Serra, Paula; Carmona, F Javier; Martínez-Cardús, Anna; Girotti, Maria Romina; Villanueva, Alberto; Guil, Sonia; Moutinho, Catia; Liz, Julia; Portela, Anna; Heyn, Holger; Moran, Sebastian; Vidal, August; Martinez-Iniesta, Maria; Manzano, Jose L; Fernandez-Figueras, Maria Teresa; Elez, Elena; Muñoz-Couselo, Eva; Botella-Estrada, Rafael; Berrocal, Alfonso; Pontén, Fredrik; Oord, Joost van den; Gallagher, William M; Frederick, Dennie T; Flaherty, Keith T; McDermott, Ultan; Lorigan, Paul; Marais, Richard; Esteller, Manel

    2015-07-01

    Metastasis is responsible for most cancer-related deaths, and, among common tumor types, melanoma is one with great potential to metastasize. Here we study the contribution of epigenetic changes to the dissemination process by analyzing the changes that occur at the DNA methylation level between primary cancer cells and metastases. We found a hypomethylation event that reactivates a cryptic transcript of the Rab GTPase activating protein TBC1D16 (TBC1D16-47 kDa; referred to hereafter as TBC1D16-47KD) to be a characteristic feature of the metastatic cascade. This short isoform of TBC1D16 exacerbates melanoma growth and metastasis both in vitro and in vivo. By combining immunoprecipitation and mass spectrometry, we identified RAB5C as a new TBC1D16 target and showed that it regulates EGFR in melanoma cells. We also found that epigenetic reactivation of TBC1D16-47KD is associated with poor clinical outcome in melanoma, while conferring greater sensitivity to BRAF and MEK inhibitors.

  20. Cell wall glycosphingolipids of Sphingomonas paucimobilis are CD1d-specific ligands for NKT cells.

    PubMed

    Sriram, Venkataraman; Du, Wenjun; Gervay-Hague, Jacquelyn; Brutkiewicz, Randy R

    2005-06-01

    The current consensus on characterization of NKT cells is based on their reactivity to the synthetic glycolipid, alpha-galactosylceramide (alpha-GalCer) in a CD1d-dependent manner. Because of the limited availability of alpha-GalCer, there is a constant search for CD1d-presented ligands that activate NKT cells. The alpha-anomericity of the carbohydrate is considered to be an important requisite for the CD1d-specific activation of NKT cells. The gram-negative, lipopolysaccharide-free bacterium Sphingomonas paucimobilis is known to contain glycosphingolipids (GSL) with alpha-anomeric sugars attached to the lipid chain. Here, we report that GSL extracted from this bacterium are able to stimulate NKT cells in a CD1d-specific manner. In addition, soluble CD1d-Ig dimers loaded with this lipid extract specifically bind to NKT cells (but not conventional T cells). Further studies on the S. paucimobilis GSL could potentially lead to other natural sources of CD1d-specific ligands useful for NKT cell analyses and aimed at identifying novel therapies for a variety of disease states.

  1. Novel hollow mesoporous 1D TiO2 nanofibers as photovoltaic and photocatalytic materials

    NASA Astrophysics Data System (ADS)

    Zhang, Xiang; Thavasi, Velmurugan; Mhaisalkar, S. G.; Ramakrishna, Seeram

    2012-02-01

    Hollow mesoporous one dimensional (1D) TiO2 nanofibers are successfully prepared by co-axial electrospinning of a titanium tetraisopropoxide (TTIP) solution with two immiscible polymers; polyethylene oxide (PEO) and polyvinylpyrrolidone (PVP) using a core-shell spinneret, followed by annealing at 450 °C. The annealed mesoporous TiO2 nanofibers are found to having a hollow structure with an average diameter of 130 nm. Measurements using the Brunauer-Emmett-Teller (BET) method reveal that hollow mesoporous TiO2 nanofibers possess a high surface area of 118 m2 g-1 with two types of mesopores; 3.2 nm and 5.4 nm that resulted from gaseous removal of PEO and PVP respectively during annealing. With hollow mesoporous TiO2 nanofibers as the photoelectrode in dye sensitized solar cells (DSSC), the solar-to-current conversion efficiency (η) and short circuit current (Jsc) are measured as 5.6% and 10.38 mA cm-2 respectively, which are higher than those of DSSC made using regular TiO2 nanofibers under identical conditions (η = 4.2%, Jsc = 8.99 mA cm-2). The improvement in the conversion efficiency is mainly attributed to the higher surface area and mesoporous TiO2 nanostructure. It facilitates the adsorption of more dye molecules and also promotes the incident photon to electron conversion. Hollow mesoporous TiO2 nanofibers with close packing of grains and crystals intergrown with each other demonstrate faster electron diffusion, and longer electron recombination time than regular TiO2 nanofibers as well as P25 nanoparticles. The surface effect of hollow mesoporous TiO2 nanofibers as a photocatalyst for the degradation of rhodamine dye was also investigated. The kinetic study shows that the hollow mesoporous surface of the TiO2 nanofibers influenced its interactions with the dye, and resulted in an increased catalytic activity over P25 TiO2 nanocatalysts.Hollow mesoporous one dimensional (1D) TiO2 nanofibers are successfully prepared by co-axial electrospinning of a titanium

  2. Microfluidic crystallization.

    PubMed

    Leng, Jacques; Salmon, Jean-Baptiste

    2009-01-01

    Microfluidics offers a wide range of new tools that permit one to revisit the formation of crystals in solution and yield insights into crystallization processes. We review such recent microfluidic devices and particularly emphasize lab-on-chips dedicated to the high-throughput screening of crystallization conditions of proteins with nanolitre consumption. We also thoroughly discuss the possibilities offered by the microfluidic tools to acquire thermodynamic and kinetic data that may improve industrial processes and shed a new light on nucleation and growth mechanisms.

  3. Crystal Furnace

    NASA Technical Reports Server (NTRS)

    1985-01-01

    A "melt recharging" technique which eliminates the cooldown and heating periods in a crystal "growing" crucible, resulted from a Jet Propulsion Laboratory (JPL)/Kayex Corporation program. Previously, the cost of growing the silicon solar cells had been very high. The JPL/Kayex system improved productivity by serially growing crystals from the same crucible using a melt recharger which made it possible to add raw silicon to an operating crucible. An isolation value, developed by Kayex, allowed the hopper to be lowered into the crucible without disturbing the inert gas atmosphere. The resulting product, a CG6000 crystal growing furnace, has become the company's major product.

  4. Structural variation from heterometallic cluster-based 1D chain to heterometallic tetranuclear cluster: Syntheses, structures and magnetic properties

    SciTech Connect

    Zhang, Shu-Hua; Zhao, Ru-Xia; Li, He-Ping; Ge, Cheng-Min; Li, Gui; Huang, Qiu-Ping; Zou, Hua-Hong

    2014-08-15

    Using the solvothermal method, we present the comparative preparation of ([Co{sub 3}Na(dmaep){sub 3}(ehbd)(N{sub 3}){sub 3}]·DMF){sub n} (1) and [Co{sub 2}Na{sub 2}(hmbd){sub 4}(N{sub 3}){sub 2}(DMF){sub 2}] (2), where Hehbd is 3-ethoxy-2-hydroxy-benzaldehyde, Hhmbd is 3-methoxy-2-hydroxy-benzaldehyde, and Hdmaep is 2-dimethylaminomethyl-6-ethoxy-phenol, which was synthesized by an in-situ reaction. Complexes 1 and 2 were characterized by elemental analysis, IR spectroscopy, and X-ray single-crystal diffraction. Complex 1 is a novel heterometallic cluster-based 1-D chain and 2 is a heterometallic tetranuclear cluster. The (Co{sub 3}{sup II}Na) and (Co{sub 2}{sup II}Na{sub 2}) cores display dominant ferromagnetic interaction from the nature of the binding modes through μ{sub 1,1,1}-N{sub 3}{sup –} (end-on, EO). - Graphical abstract: Two novel cobalt complexes have been prepared. Compound 1 consists of tetranuclear (Co{sub 3}{sup II}Na) units, which further formed a 1-D chain. Compound 2 is heterometallic tetranuclear cluster. Two complexes display dominant ferromagnetic interaction. - Highlights: • Two new heterometallic complexes have been synthesized by solvothermal method. • The stereospecific blockade of the ligands in the synthesis system seems to be the most important synthetic parameter. • The magnetism studies show that 1 and 2 exhibit ferromagnetic interactions. • Complex 1 shows slowing down of magnetization and not blocking of magnetization.

  5. Assessing 1D Atmospheric Solar Radiative Transfer Models: Interpretation and Handling of Unresolved Clouds.

    NASA Astrophysics Data System (ADS)

    Barker, H. W.; Stephens, G. L.; Partain, P. T.; Bergman, J. W.; Bonnel, B.; Campana, K.; Clothiaux, E. E.; Clough, S.; Cusack, S.; Delamere, J.; Edwards, J.; Evans, K. F.; Fouquart, Y.; Freidenreich, S.; Galin, V.; Hou, Y.; Kato, S.; Li, J.;  Mlawer, E.;  Morcrette, J.-J.;  O'Hirok, W.;  Räisänen, P.;  Ramaswamy, V.;  Ritter, B.;  Rozanov, E.;  Schlesinger, M.;  Shibata, K.;  Sporyshev, P.;  Sun, Z.;  Wendisch, M.;  Wood, N.;  Yang, F.

    2003-08-01

    The primary purpose of this study is to assess the performance of 1D solar radiative transfer codes that are used currently both for research and in weather and climate models. Emphasis is on interpretation and handling of unresolved clouds. Answers are sought to the following questions: (i) How well do 1D solar codes interpret and handle columns of information pertaining to partly cloudy atmospheres? (ii) Regardless of the adequacy of their assumptions about unresolved clouds, do 1D solar codes perform as intended?One clear-sky and two plane-parallel, homogeneous (PPH) overcast cloud cases serve to elucidate 1D model differences due to varying treatments of gaseous transmittances, cloud optical properties, and basic radiative transfer. The remaining four cases involve 3D distributions of cloud water and water vapor as simulated by cloud-resolving models. Results for 25 1D codes, which included two line-by-line (LBL) models (clear and overcast only) and four 3D Monte Carlo (MC) photon transport algorithms, were submitted by 22 groups. Benchmark, domain-averaged irradiance profiles were computed by the MC codes. For the clear and overcast cases, all MC estimates of top-of-atmosphere albedo, atmospheric absorptance, and surface absorptance agree with one of the LBL codes to within ±2%. Most 1D codes underestimate atmospheric absorptance by typically 15-25 W m-2 at overhead sun for the standard tropical atmosphere regardless of clouds.Depending on assumptions about unresolved clouds, the 1D codes were partitioned into four genres: (i) horizontal variability, (ii) exact overlap of PPH clouds, (iii) maximum/random overlap of PPH clouds, and (iv) random overlap of PPH clouds. A single MC code was used to establish conditional benchmarks applicable to each genre, and all MC codes were used to establish the full 3D benchmarks. There is a tendency for 1D codes to cluster near their respective conditional benchmarks, though intragenre variances typically exceed those for

  6. Benchmarks and models for 1-D radiation transport in stochastic participating media

    SciTech Connect

    Miller, D S

    2000-08-21

    Benchmark calculations for radiation transport coupled to a material temperature equation in a 1-D slab and 1-D spherical geometry binary random media are presented. The mixing statistics are taken to be homogeneous Markov statistics in the 1-D slab but only approximately Markov statistics in the 1-D sphere. The material chunk sizes are described by Poisson distribution functions. The material opacities are first taken to be constant and then allowed to vary as a strong function of material temperature. Benchmark values and variances for time evolution of the ensemble average of material temperature energy density and radiation transmission are computed via a Monte Carlo type method. These benchmarks are used as a basis for comparison with three other approximate methods of solution. One of these approximate methods is simple atomic mix. The second approximate model is an adaptation of what is commonly called the Levermore-Pomraning model and which is referred to here as the standard model. It is shown that recasting the temperature coupling as a type of effective scattering can be useful in formulating the third approximate model, an adaptation of a model due to Su and Pomraning which attempts to account for the effects of scattering in a stochastic context. This last adaptation shows consistent improvement over both the atomic mix and standard models when used in the 1-D slab geometry but shows limited improvement in the 1-D spherical geometry. Benchmark values are also computed for radiation transmission from the 1-D sphere without material heating present. This is to evaluate the performance of the standard model on this geometry--something which has never been done before. All of the various tests demonstrate the importance of stochastic structure on the solution. Also demonstrated are the range of usefulness and limitations of a simple atomic mix formulation.

  7. Turned on by danger: activation of CD1d-restricted invariant natural killer T cells.

    PubMed

    Lawson, Victoria

    2012-09-01

    CD1d-restricted invariant natural killer T (iNKT) cells bear characteristics of innate and adaptive lymphocytes, which allow them to bridge the two halves of the immune response and play roles in many disease settings. Recent work has characterized precisely how their activation is initiated and regulated. Novel antigens from important pathogens have been identified, as has an abundant self-antigen, β-glucopyranosylcaramide, capable of mediating an iNKT-cell response. Studies of the iNKT T-cell receptor (TCR)-antigen-CD1d complex show how docking between CD1d-antigen and iNKT TCR is highly conserved, and how small sequence differences in the TCR establish intrinsic variation in iNKT TCR affinity. The sequence of the TCR CDR3β loop determines iNKT TCR affinity for ligand-CD1d, independent of ligand identity. CD1d ligands can promote T helper type 1 (Th1) or Th2 biased cytokine responses, depending on the composition of their lipid tails. Ligands loaded into CD1d on the cell surface promote Th2 responses, whereas ligands with long hydrophobic tails are loaded endosomally and promote Th1 responses. This information is informing the design of synthetic iNKT-cell antigens. The iNKT cells may be activated by exogenous antigen, or by a combination of dendritic cell-derived interleukin-12 and iNKT TCR-self-antigen-CD1d engagement. The iNKT-cell activation is further modulated by recent foreign or self-antigen encounter. Activation of dendritic cells through pattern recognition receptors alters their antigen presentation and cytokine production, strongly influencing iNKT-cell activation. In a range of bacterial infections, dendritic cell-dependent innate activation of iNKT cells through interleukin-12 is the dominant influence on their activity.

  8. Designing Heterogeneous 1D Nanostructure Arrays Based on AAO Templates for Energy Applications.

    PubMed

    Wen, Liaoyong; Wang, Zhijie; Mi, Yan; Xu, Rui; Yu, Shu-Hong; Lei, Yong

    2015-07-01

    In order to fulfill the multiple requirements for energy production, storage, and utilization in the future, the conventional planar configuration of current energy conversion/storage devices has to be reformed, since technological evolution has promoted the efficiency of the corresponding devices to be close to the theoretical values. One promising strategy is to construct multifunctional 1D nanostructure arrays to replace their planar counterparts for device fabrication, ascribing to the significant superiorities of such 1D nanostructure arrays. In the last three decades, technologies based on anodic aluminium oxide (AAO) templates have turned out to be valuable meaning for the realization of 1D nanostructures and have attracted tremendous interest. In this review, recent progress in energy-related devices equipped with heterogeneous 1D nanostructure arrays that fabricated through the assistance of AAO templates is highlighted. Particular emphasis is given on how to develop efficient devices via optimizing the componential and morphological parameters of the 1D nanostructure arrays. Finally, aspects relevant to the further improvement of device performance are discussed.

  9. VES/TEM 1D joint inversion by using Controlled Random Search (CRS) algorithm

    NASA Astrophysics Data System (ADS)

    Bortolozo, Cassiano Antonio; Porsani, Jorge Luís; Santos, Fernando Acácio Monteiro dos; Almeida, Emerson Rodrigo

    2015-01-01

    Electrical (DC) and Transient Electromagnetic (TEM) soundings are used in a great number of environmental, hydrological, and mining exploration studies. Usually, data interpretation is accomplished by individual 1D models resulting often in ambiguous models. This fact can be explained by the way as the two different methodologies sample the medium beneath surface. Vertical Electrical Sounding (VES) is good in marking resistive structures, while Transient Electromagnetic sounding (TEM) is very sensitive to conductive structures. Another difference is VES is better to detect shallow structures, while TEM soundings can reach deeper layers. A Matlab program for 1D joint inversion of VES and TEM soundings was developed aiming at exploring the best of both methods. The program uses CRS - Controlled Random Search - algorithm for both single and 1D joint inversions. Usually inversion programs use Marquadt type algorithms but for electrical and electromagnetic methods, these algorithms may find a local minimum or not converge. Initially, the algorithm was tested with synthetic data, and then it was used to invert experimental data from two places in Paraná sedimentary basin (Bebedouro and Pirassununga cities), both located in São Paulo State, Brazil. Geoelectric model obtained from VES and TEM data 1D joint inversion is similar to the real geological condition, and ambiguities were minimized. Results with synthetic and real data show that 1D VES/TEM joint inversion better recovers simulated models and shows a great potential in geological studies, especially in hydrogeological studies.

  10. A Mathematical Model of T1D Acceleration and Delay by Viral Infection.

    PubMed

    Moore, James R; Adler, Fred

    2016-03-01

    Type 1 diabetes (T1D) is often triggered by a viral infection, but the T1D prevalence is rising among populations that have a lower exposure to viral infection. In an animal model of T1D, the NOD mouse, viral infection at different ages may either accelerate or delay disease depending on the age of infection and the type of virus. Viral infection may affect the progression of T1D via multiple mechanisms: triggering inflammation, bystander activation of self-reactive T-cells, inducing a competitive immune response, or inducing a regulatory immune response. In this paper, we create mathematical models of the interaction of viral infection with T1D progression, incorporating each of these four mechanisms. Our goal is to understand how each viral mechanism interacts with the age of infection. The model predicts that each viral mechanism has a unique pattern of interaction with disease progression. Viral inflammation always accelerates disease, but the effect decreases with age of infection. Bystander activation has little effect at younger ages and actually decreases incidence at later ages while accelerating disease in mice that do get the disease. A competitive immune response to infection can decrease incidence at young ages and increase it at older ages, with the effect decreasing over time. Finally, an induced Treg response decreases incidence at any age of infection, but the effect decreases with age. Some of these patterns resemble those seen experimentally. PMID:27030351

  11. MagmaHeatNS1D: One-dimensional visualization numerical simulator for computing thermal evolution in a contact metamorphic aureole

    NASA Astrophysics Data System (ADS)

    Wang, Dayong

    2013-04-01

    MagmaHeatNS1D is an IDL (Interactive Data Language) program that is aimed at numerically modeling heat transfer from an igneous intrusion to its host rocks and providing important thermal state information for minerals and organic matters in a contact aureole. It can be used to trace temperature time series, computing the peak temperature, and evaluating organic-matter maturation in a contact aureole. The theoretical basis of the program is a complete one-dimensional heat transfer model, and, hence, the program can allow for numerous potential influencing factors on the heat transfer, involving magma crystallization, volatilization and the supercritical state of pore water, dehydration and decarbonation reactions of host rock matrix, instantaneous and finite-time magma intrusion mechanisms, and hydrothermal convection in host rocks. This ensures that the program can be applicable to study different igneous intrusions in various geological conditions. MagmaHeatNS1D features a graphical user interface for controlling program execution, displaying real-time results, outputting final results, and opening secondary windows which serve to input the model parameters. MagmaHeatNS1D can be used in an intuitive framework for educational and research purposes.

  12. Ice Concentration Retrieval in Stratiform Mixed-phase Clouds Using Cloud Radar Reflectivity Measurements and 1D Ice Growth Model Simulations

    SciTech Connect

    Zhang, Damao; Wang, Zhien; Heymsfield, Andrew J.; Fan, Jiwen; Luo, Tao

    2014-10-01

    Measurement of ice number concentration in clouds is important but still challenging. Stratiform mixed-phase clouds (SMCs) provide a simple scenario for retrieving ice number concentration from remote sensing measurements. The simple ice generation and growth pattern in SMCs offers opportunities to use cloud radar reflectivity (Ze) measurements and other cloud properties to infer ice number concentration quantitatively. To understand the strong temperature dependency of ice habit and growth rate quantitatively, we develop a 1-D ice growth model to calculate the ice diffusional growth along its falling trajectory in SMCs. The radar reflectivity and fall velocity profiles of ice crystals calculated from the 1-D ice growth model are evaluated with the Atmospheric Radiation Measurements (ARM) Climate Research Facility (ACRF) ground-based high vertical resolution radar measurements. Combining Ze measurements and 1-D ice growth model simulations, we develop a method to retrieve the ice number concentrations in SMCs at given cloud top temperature (CTT) and liquid water path (LWP). The retrieved ice concentrations in SMCs are evaluated with in situ measurements and with a three-dimensional cloud-resolving model simulation with a bin microphysical scheme. These comparisons show that the retrieved ice number concentrations are within an uncertainty of a factor of 2, statistically.

  13. Breakdown current density in h-BN-capped quasi-1D TaSe3 metallic nanowires: prospects of interconnect applications.

    PubMed

    Stolyarov, Maxim A; Liu, Guanxiong; Bloodgood, Matthew A; Aytan, Ece; Jiang, Chenglong; Samnakay, Rameez; Salguero, Tina T; Nika, Denis L; Rumyantsev, Sergey L; Shur, Michael S; Bozhilov, Krassimir N; Balandin, Alexander A

    2016-08-25

    We report on the current-carrying capacity of the nanowires made from the quasi-1D van der Waals metal tantalum triselenide capped with quasi-2D boron nitride. The chemical vapor transport method followed by chemical and mechanical exfoliation were used to fabricate the mm-long TaSe3 wires with the lateral dimensions in the 20 to 70 nm range. Electrical measurements establish that the TaSe3/h-BN nanowire heterostructures have a breakdown current density exceeding 10 MA cm(-2)-an order-of-magnitude higher than that for copper. Some devices exhibited an intriguing step-like breakdown, which can be explained by the atomic thread bundle structure of the nanowires. The quasi-1D single crystal nature of TaSe3 results in a low surface roughness and in the absence of the grain boundaries. These features can potentially enable the downscaling of the nanowires to lateral dimensions in a few-nm range. Our results suggest that quasi-1D van der Waals metals have potential for applications in the ultimately downscaled local interconnects. PMID:27531559

  14. Four 1-D metal-organic polymers self-assembled from semi-flexible benzimidazole-based ligand: Syntheses, structures and fluorescent properties

    NASA Astrophysics Data System (ADS)

    Zhou, Chun-lin; Wang, Shi-min; Liu, Sai-nan; Yu, Tian-tian; Li, Rui-ying; Xu, Hong; Liu, Zhong-yi; Sun, Huan; Cheng, Jia-jia; Li, Jin-peng; Hou, Hong-wei; Chang, Jun-biao

    2016-08-01

    Four one-dimensional (1-D) metal-organic polymers based on methylene-bis(1,1‧-benzimidazole)(mbbz), namely, {[Hg(mbbz)(SCN)2]·1/3H2O}n (1), [Co(mbbz)(Cl)2]n (2), {[Co(mbbz)(SO4)]·CH3OH}n (3) and {[Zn(mbbz)(SO4)]·CH3OH}n (4) have been successfully synthesized and structurally characterized. Single-crystal X-ray diffraction reveals that polymers 1 and 2 exhibit interesting 1-D double helical chain structures, while polymers 3 and 4 are 1-D double chain structures due to the bridging effect of mbbz ligands and sulfate anions. These polymers containing the mbbz-based ligand have a high degree of dependence on the corresponding counter anions. Furthermore, the fluorescence properties of the four polymers were also investigated in the solid state, showing the fluorescence signal changes in comparing with that of free ligand mbbz.

  15. A Tale of Copper Coordination Frameworks: Controlled Single-Crystal-to-Single-Crystal Transformations and Their Catalytic C-H Bond Activation Properties.

    PubMed

    Chen, Yifa; Feng, Xiao; Huang, Xianqiang; Lin, Zhengguo; Pei, Xiaokun; Li, Siqing; Li, Jikun; Wang, Shan; Li, Rui; Wang, Bo

    2015-09-28

    Metal-organic frameworks (MOFs), as a class of microporous materials with well-defined channels and rich functionalities, hold great promise for various applications. Yet the formation and crystallization processes of various MOFs with distinct topology, connectivity, and properties remain largely unclear, and the control of such processes is rather challenging. Starting from a 0D Cu coordination polyhedron, MOP-1, we successfully unfolded it to give a new 1D-MOF by a single-crystal-to-single-crystal (SCSC) transformation process at room temperature as confirmed by SXRD. We also monitored the continuous transformation states by FTIR and PXRD. Cu MOFs with 2D and 3D networks were also obtained from this 1D-MOF by SCSC transformations. Furthermore, Cu MOFs with 0D, 1D, and 3D networks, MOP-1, 1D-MOF, and HKUST-1, show unique performances in the kinetics of the C-H bond catalytic oxidation reaction.

  16. Measurement of tropospheric 300 nm solar ultraviolet flux for determination of O/1D/ photoproduction rate

    NASA Technical Reports Server (NTRS)

    Sellers, B.; Hanser, F. A.

    1978-01-01

    The tropospheric importance of the OH radical, and the reaction scheme that leads to its formation, are now being widely investigated. Ozone photolysis at wavelengths no greater than 318 nm produces O(1D), a small fraction of which then reacts with water vapor to yield OH. Although experimental data are available for the O(1D) quantum yield, as well as the O3 absorption cross section, all previous tropospheric photochemical models have had to use theoretical calculations to determine the UV flux. Discussed in this paper are aircraft spectral measurements of the solar UV flux at two altitudes - 2 and 6 km. These results have been compared with three theoretical approaches. The measured experimental fluxes have been combined here with recent quantum yield data to calculate the O(1D) photoproduction rate for various albedo values. This rate is larger than that used in models by about a factor of 2 for reasonable values of assumed albedo.

  17. A comparison of 1D and 2D LSTM architectures for the recognition of handwritten Arabic

    NASA Astrophysics Data System (ADS)

    Yousefi, Mohammad Reza; Soheili, Mohammad Reza; Breuel, Thomas M.; Stricker, Didier

    2015-01-01

    In this paper, we present an Arabic handwriting recognition method based on recurrent neural network. We use the Long Short Term Memory (LSTM) architecture, that have proven successful in different printed and handwritten OCR tasks. Applications of LSTM for handwriting recognition employ the two-dimensional architecture to deal with the variations in both vertical and horizontal axis. However, we show that using a simple pre-processing step that normalizes the position and baseline of letters, we can make use of 1D LSTM, which is faster in learning and convergence, and yet achieve superior performance. In a series of experiments on IFN/ENIT database for Arabic handwriting recognition, we demonstrate that our proposed pipeline can outperform 2D LSTM networks. Furthermore, we provide comparisons with 1D LSTM networks trained with manually crafted features to show that the automatically learned features in a globally trained 1D LSTM network with our normalization step can even outperform such systems.

  18. Collective mode damping and viscosity in a 1D unitary Fermi gas

    NASA Astrophysics Data System (ADS)

    Punk, M.; Zwerger, W.

    2006-08-01

    We calculate the damping of the Bogoliubov Anderson mode in a one-dimensional (1D) two-component attractive Fermi gas for arbitrary coupling strength within a quantum hydrodynamic approach. Using the Bethe-ansatz solution of the 1D BCS-BEC crossover problem, we derive analytic results for the viscosity covering the full range from a Luther Emery liquid of weakly bound pairs to a Lieb Liniger gas of strongly bound bosonic dimers. At the unitarity point, the system is a Tonks Girardeau gas with a universal constant αζ = 0.38 in the viscosity ζ = αζplanck n for T = 0. For the trapped case, we calculate the Q-factor of the breathing mode and show that the damping provides a sensitive measure of temperature in 1D Fermi gases.

  19. TBC1D24 mutation causes autosomal-dominant nonsyndromic hearing loss.

    PubMed

    Azaiez, Hela; Booth, Kevin T; Bu, Fengxiao; Huygen, Patrick; Shibata, Seiji B; Shearer, A Eliot; Kolbe, Diana; Meyer, Nicole; Black-Ziegelbein, E Ann; Smith, Richard J H

    2014-07-01

    Hereditary hearing loss is extremely heterogeneous. Over 70 genes have been identified to date, and with the advent of massively parallel sequencing, the pace of novel gene discovery has accelerated. In a family segregating progressive autosomal-dominant nonsyndromic hearing loss (NSHL), we used OtoSCOPE® to exclude mutations in known deafness genes and then performed segregation mapping and whole-exome sequencing to identify a unique variant, p.Ser178Leu, in TBC1D24 that segregates with the hearing loss phenotype. TBC1D24 encodes a GTPase-activating protein expressed in the cochlea. Ser178 is highly conserved across vertebrates and its change is predicted to be damaging. Other variants in TBC1D24 have been associated with a panoply of clinical symptoms including autosomal recessive NSHL, syndromic hearing impairment associated with onychodystrophy, osteodystrophy, mental retardation, and seizures (DOORS syndrome), and a wide range of epileptic disorders. PMID:24729539

  20. ISUAL side-way observations of the OI(1D) night airglows

    NASA Astrophysics Data System (ADS)

    Chiang, C.; Chang, T.; Lin, C.; Rajesh, P.; Liu, J.; Chen, A. B.; Su, H.; Hsu, R.

    2008-12-01

    Recently, ISUAL/FORMOSAT-2 Satellite has devoted more observation time to investigate the OI(1D) nightglow from the sideway, which provides the first comprehensive survey of 630.0nm emission in the pre- midnight sector at F layer. It is found that the OI(1D) nightglow enhancement exhibited remarkable seasonal variations. In this study, we want to highlight the following three points. First, semiannual anomaly and winter anomaly existed in the form of the brightening emission in the region of equatorial anomaly. Second, the data indicates that the tidally enhanced regions show significant longitudinal variability. Third, the latitudinal variability of OI(1D) nightglow can be contributed to both the Equatorial Ionization Anomaly (EIA) effect and the upward propagation tides.

  1. S-duality constraints on 1D patterns associated with fractional quantum Hall states.

    PubMed

    Seidel, Alexander

    2010-07-01

    Using the modular invariance of the torus, constraints on the 1D patterns are derived that are associated with various fractional quantum Hall ground states, e.g., through the thin torus limit. In the simplest case, these constraints enforce the well-known odd-denominator rule, which is seen to be a necessary property of all 1D patterns associated to quantum Hall states with minimum torus degeneracy. However, the same constraints also have implications for the non-Abelian states possible within this framework. In simple cases, including the ν=1 Moore-Read state and the ν=3/2 level 3 Read-Rezayi state, the filling factor and the torus degeneracy uniquely specify the possible patterns, and thus all physical properties that are encoded in them. It is also shown that some states, such as the "strong p-wave pairing state," cannot in principle be described through 1D patterns.

  2. Liquid Crystals

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Thermochromic liquid crystals, or TLCs, are a type of liquid crystals that react to changes in temperature by changing color. The Hallcrest/NASA collaboration involved development of a new way to visualize boundary layer transition in flight and in wind tunnel testing of aircraft wing and body surfaces. TLCs offered a new and potentially better method of visualizing the boundary layer transition in flight. Hallcrest provided a liquid crystal formulation technique that afforded great control over the sensitivity of the liquid crystals to varying conditions. Method is of great use to industry, government and universities for aerodynamic and hydrodynamic testing. Company's principal line is temperature indicating devices for industrial use, such as non-destructive testing and flaw detection in electric/electronic systems, medical application, such as diagnostic systems, for retail sale, such as room, refrigerator, baby bath and aquarium thermometers, and for advertising and promotion specials. Additionally, Hallcrest manufactures TLC mixtures for cosmetic applications, and liquid crystal battery tester for Duracell batteries.

  3. Targeted disruption of CD1d prevents NKT cell development in pigs

    PubMed Central

    Yang, Guan; Artiaga, Bianca L.; Hackmann, Timothy J.; Samuel, Melissa S.; Walters, Eric M; Salek-Ardakani, Shahram; Driver, John P.

    2016-01-01

    Studies in mice genetically lacking natural killer T (NKT) cells show that these lymphocytes make important contributions to both innate and adaptive immune responses. However, the usefulness of murine models to study human NKT cells is limited by the many differences between mice and humans, including that their NKT cell frequencies, subsets and distribution are dissimilar. A more suitable model may be swine that share many metabolic, physiological and growth characteristics with humans and are also similar for NKT cells. Thus, we analyzed genetically modified pigs made deficient for CD1d that is required for the development of Type I invariant NKT (iNKT) cells that express a semi-invariant T cell receptor (TCR) and Type II NKT cells that use variable TCRs. Peripheral blood analyzed by flow cytometry and interferon-γ (IFNγ) enzyme-linked immuno spot (ELISPOT) assays demonstrated that CD1d-knockout pigs completely lack iNKT cells while other leukocyte populations remain intact. CD1d and NKT cells have been shown to be involved in shaping the composition of the commensal microbiota in mice. Therefore, we also compared the fecal microbiota profile between pigs expressing and lacking NKT cells. However, no differences were found between pigs lacking or expressing CD1d. Our results are the first to show that knocking-out CD1d prevents the development of iNKT cells in a non-rodent species. CD1d-deficient pigs should offer a useful model to more accurately determine the contribution of NKT cells for human immune responses. They also have potential for understanding how NKT cells impact the health of commercial swine. PMID:25930071

  4. Characterisation and improvement of j(O1D) filter radiometers

    NASA Astrophysics Data System (ADS)

    Bohn, Birger; Heard, Dwayne E.; Mihalopoulos, Nikolaos; Plass-Dülmer, Christian; Schmitt, Rainer; Whalley, Lisa K.

    2016-07-01

    Atmospheric O3 → O(1D) photolysis frequencies j(O1D) are crucial parameters for atmospheric photochemistry because of their importance for primary OH formation. Filter radiometers have been used for many years for in situ field measurements of j(O1D). Typically the relationship between the output of the instruments and j(O1D) is non-linear because of changes in the shape of the solar spectrum dependent on solar zenith angles and total ozone columns. These non-linearities can be compensated for by a correction method based on laboratory measurements of the spectral sensitivity of the filter radiometer and simulated solar actinic flux density spectra. Although this correction is routinely applied, the results of a previous field comparison study of several filter radiometers revealed that some corrections were inadequate. In this work the spectral characterisations of seven instruments were revised, and the correction procedures were updated and harmonised considering recent recommendations of absorption cross sections and quantum yields of the photolysis process O3 → O(1D). Previous inconsistencies were largely removed using these procedures. In addition, optical interference filters were replaced to improve the spectral properties of the instruments. Successive determinations of spectral sensitivities and field comparisons of the modified instruments with a spectroradiometer reference confirmed the improved performance. Overall, filter radiometers remain a low-maintenance alternative of spectroradiometers for accurate measurements of j(O1D) provided their spectral properties are known and potential drifts in sensitivities are monitored by regular calibrations with standard lamps or reference instruments.

  5. Combining complementary multiple bandgaps in one-dimensional plasma photonic crystal heterostructures

    NASA Astrophysics Data System (ADS)

    Zhang, Juan; Zou, Junhui; Wang, Yang

    2016-10-01

    A single bandgap overlapping scheme is often used to enlarge the photonic bandgap (PBG) range in cascaded or hetero one-dimensional photonic crystal (1D PC) structures. In this paper, we design an optimized one-dimensional plasma photonic crystal (1D PPC) heterostructure based on the idea of combining complementary multiple PBGs to enlarge the PBG range. The flexibility of the PBG of a 1D PPC, caused by the frequency-dependent dispersive properties of plasma, is helpful for generating and combining multiple bandgaps. The obtained omni-directional photonic bandgap (ODPBG) width for the 1D PPC heterostructure is dramatically enhanced compared with that of a single 1D PPC alone and is much larger than that of 1D PC heterostructures described in the previous works. Further study shows that the PPC heterostructures are more suitable than other heterostructures (such as a 1D PC heterostructure or heterostructures composed of a 1D PPC and 1D PC) for combining complementary PBGs. The ODPBG ranges for 1D PPC heterostructures can be further extended by adjusting the parameters of the plasma to allow more complementary PBGs to combine with each other.

  6. Synthesis and characterization of 1D iron(II) spin crossover coordination polymers with hysteresis.

    PubMed

    Bauer, Wolfgang; Lochenie, Charles; Weber, Birgit

    2014-02-01

    Purposeful ligand design was used for the synthesis of eight new 1D iron(II) spin crossover coordination polymers aiming for cooperative spin transitions with hysteresis. The results from magnetic measurements and X-ray structure analysis show that the combination of rigid linkers and a hydrogen bond network between the 1D chains is a promising tool to reach this goal. Five of the eight new samples show a cooperative spin transition with hysteresis with up to 43 K wide hysteresis loops.

  7. Quench dynamics of 1D spin-imbalanced Fermi-Hubbard model

    NASA Astrophysics Data System (ADS)

    Yin, Xiao; Radzihovsky, Leo

    We study a non-equilibrium dynamics of a 1D spin-imbalanced Fermi-Hubbard model following a quantum quench of on-site interaction, using bosonization and exact analysis. By focusing on the evolution of singlet-, triplet-, density and magnetization correlation functions, we find that the evolution and the final state display a strong dependence on the initial state. Thus, we demonstrate that such quantum quench may be used as a new approach to identify and probe the 1D gapless analogue of the elusive FFLO state. Supported by NSF through DMR-1001240 and by Simons Investigator award from Simons.

  8. Opto-digital image encryption by using Baker mapping and 1-D fractional Fourier transform

    NASA Astrophysics Data System (ADS)

    Liu, Zhengjun; Li, She; Liu, Wei; Liu, Shutian

    2013-03-01

    We present an optical encryption method based on the Baker mapping in one-dimensional fractional Fourier transform (1D FrFT) domains. A thin cylinder lens is controlled by computer for implementing 1D FrFT at horizontal direction or vertical direction. The Baker mapping is introduced to scramble the amplitude distribution of complex function. The amplitude and phase of the output of encryption system are regarded as encrypted image and key. Numerical simulation has been performed for testing the validity of this encryption scheme.

  9. 50 CFR Table 1d to Part 660... - At-Sea Whiting Fishery Annual Set-Asides, 2013

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 13 2014-10-01 2014-10-01 false At-Sea Whiting Fishery Annual Set-Asides, 2013 1d Table 1d to Part 660, Subpart C Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE (CONTINUED) FISHERIES OFF WEST COAST STATES Pt. 660, Subpt. C, Table 1d...

  10. 50 CFR Table 1d to Part 660... - At-Sea Whiting Fishery Annual Set-Asides, 2013

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 13 2013-10-01 2013-10-01 false At-Sea Whiting Fishery Annual Set-Asides, 2013 1d Table 1d to Part 660, Subpart C Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE (CONTINUED) FISHERIES OFF WEST COAST STATES Pt. 660, Subpt. C, Table 1d...

  11. Crystal Orientation Change and Its Origin in One-Dimensional Nanoconfinement Constructed by Polystyrene-block-poly(ethylene oxide) Single Crystal Mats

    SciTech Connect

    Hsiao, M.; Zheng, J; Leng, S; Van Horn, R; Quirk, R; Thomas, E; Chen, H; Hsiao, B; Rong, L; et. al.

    2008-01-01

    Utilizing crystalline-amorphous block copolymers, such as in the case of polystyrene-block-poly(ethylene oxide) (PS-b-PEO), under a large amplitude shear process provides an opportunity for investigating crystal growth and orientation within nanoconfinements at different supercoolings. However, the internal stress generated during the shearing process and the structural defects embedded in the phase-separated morphology inevitably play roles in affecting the confinement effect on the crystallization of the crystalline blocks. In this study, we designed a one-dimensional (1D), defect-free confinement constructed by PS-b-PEO single crystal mats collected in dilute solution. Each single crystal possessed a square-shaped, 'sandwiched' lamellar structure, and it consisted of a PEO single crystal layer between two PS nanolayers formed by the tethered PS blocks on the PEO single crystal top and bottom fold surfaces. Furthermore, in these single crystal mats the glass transition temperature of the PS blocks is higher than the melting temperature of the PEO single crystals. We melted the PEO crystals between the two vitrified PS nanolayers, and the PEO blocks were recrystallized isothermally by quenching the mats to preset recrystallization temperatures (T{sub rx}). The results showed that this change of the PEO crystal orientation takes place within a few degrees Celsius. Microscopically, the crystal orientation might be determined from the status of critical nuclei formation due to the size and shape of this 1D confinement. This likely included a competition between the high tethering density (the junctions) of the PEO blocks at the PS interfaces leading to the homeotropic orientation with an anisotropic conformational orientation of the PEO blocks in the melt and the anisotropic density fluctuations within the 1D confined layer which could lead to an anisotropic ability for the PEO blocks to overcome the nucleation barrier to form the homogeneous orientation. The

  12. Noncovalent-bonded 1D-3D supramolecular architectures from 2-methylquinoline/quinoline with monocarboxylic acid and dicarboxylic acid

    NASA Astrophysics Data System (ADS)

    Gao, Xingjun; Jin, Shouwen; Jin, Li; Ye, XiangHang; Zheng, Lu; Li, JingWen; Jin, BinPeng; Wang, Daqi

    2014-10-01

    Studies concentrating on noncovalent weak interactions between the organic base of 2-methylquinoline/quinoline, and carboxylic acid derivatives have led to an increased understanding of the role 2-methylquinoline/quinoline have in binding with carboxylic acids. Here anhydrous multicomponent organic acid-base adducts of 2-methylquinoline/quinoline have been prepared with carboxylic acids that ranged from monocarboxylic acid to dicarboxylic acid such as p-nitrobenzoic acid, (4-chloro-phenoxy)-acetic acid, 4-hydroxy-benzoic acid, 5-bromosalicylic acid, 2,4-dihydroxybenzoic acid, α-ketoglutaric acid, and 4-nitrophthalic acid. The seven crystalline complexes were characterized by X-ray diffraction analysis, IR, m.p., and elemental analysis. These structures adopted the hetero supramolecular synthons. Analysis of the crystal packing of 1-7 suggests that there are Nsbnd H⋯O, Osbnd H⋯N, and Osbnd H⋯O hydrogen bonds (charge assisted or neutral) between the acid and quinoline moieties in the studied compounds. Except the classical hydrogen bonding interactions, the secondary propagating interactions also play important roles in structure extension. These weak interactions combined, these compounds displayed 1D-3D framework structure.

  13. Epitaxial 1D electron transport layers for high-performance perovskite solar cells

    NASA Astrophysics Data System (ADS)

    Han, Gill Sang; Chung, Hyun Suk; Kim, Dong Hoe; Kim, Byeong Jo; Lee, Jin-Wook; Park, Nam-Gyu; Cho, In Sun; Lee, Jung-Kun; Lee, Sangwook; Jung, Hyun Suk

    2015-09-01

    We demonstrate high-performance perovskite solar cells with excellent electron transport properties using a one-dimensional (1D) electron transport layer (ETL). The 1D array-based ETL is comprised of 1D SnO2 nanowires (NWs) array grown on a F:SnO2 transparent conducting oxide substrate and rutile TiO2 nanoshells epitaxially grown on the surface of the 1D SnO2 NWs. The optimized devices show more than 95% internal quantum yield at 750 nm, and a power conversion efficiency (PCE) of 14.2%. The high quantum yield is attributed to dramatically enhanced electron transport in the epitaxial TiO2 layer, compared to that in conventional nanoparticle-based mesoporous TiO2 (mp-TiO2) layers. In addition, the open space in the 1D array-based ETL increases the prevalence of uniform TiO2/perovskite junctions, leading to reproducible device performance with a high fill factor. This work offers a method to achieve reproducible, high-efficiency perovskite solar cells with high-speed electron transport.We demonstrate high-performance perovskite solar cells with excellent electron transport properties using a one-dimensional (1D) electron transport layer (ETL). The 1D array-based ETL is comprised of 1D SnO2 nanowires (NWs) array grown on a F:SnO2 transparent conducting oxide substrate and rutile TiO2 nanoshells epitaxially grown on the surface of the 1D SnO2 NWs. The optimized devices show more than 95% internal quantum yield at 750 nm, and a power conversion efficiency (PCE) of 14.2%. The high quantum yield is attributed to dramatically enhanced electron transport in the epitaxial TiO2 layer, compared to that in conventional nanoparticle-based mesoporous TiO2 (mp-TiO2) layers. In addition, the open space in the 1D array-based ETL increases the prevalence of uniform TiO2/perovskite junctions, leading to reproducible device performance with a high fill factor. This work offers a method to achieve reproducible, high-efficiency perovskite solar cells with high-speed electron transport

  14. Strongly-Refractive One-Dimensional Photonic Crystal Prisms

    NASA Technical Reports Server (NTRS)

    Ting, David Z. (Inventor)

    2004-01-01

    One-dimensional (1D) photonic crystal prisms can separate a beam of polychromatic electromagnetic waves into constituent wavelength components and can utilize unconventional refraction properties for wavelength dispersion over significant portions of an entire photonic band rather than just near the band edges outside the photonic band gaps. Using a ID photonic crystal simplifies the design and fabrication process and allows the use of larger feature sizes. The prism geometry broadens the useful wavelength range, enables better optical transmission, and exhibits angular dependence on wavelength with reduced non-linearity. The properties of the 1 D photonic crystal prism can be tuned by varying design parameters such as incidence angle, exit surface angle, and layer widths. The ID photonic crystal prism can be fabricated in a planar process, and can be used as optical integrated circuit elements.

  15. A South American Prehistoric Mitogenome: Context, Continuity, and the Origin of Haplogroup C1d

    PubMed Central

    Sans, Mónica; Figueiro, Gonzalo; Hughes, Cris E.; Lindo, John; Hidalgo, Pedro C.; Malhi, Ripan S.

    2015-01-01

    Based on mitochondrial DNA (mtDNA), it has been estimated that at least 15 founder haplogroups peopled the Americas. Subhaplogroup C1d3 was defined based on the mitogenome of a living individual from Uruguay that carried a lineage previously identified in hypervariable region I sequences from ancient and modern Uruguayan individuals. When complete mitogenomes were studied, additional substitutions were found in the coding region of the mitochondrial genome. Using a complete ancient mitogenome and three modern mitogenomes, we aim to clarify the ancestral state of subhaplogroup C1d3 and to better understand the peopling of the region of the Río de la Plata basin, as well as of the builders of the mounds from which the ancient individuals were recovered. The ancient mitogenome, belonging to a female dated to 1,610±46 years before present, was identical to the mitogenome of one of the modern individuals. All individuals share the mutations defining subhaplogroup C1d3. We estimated an age of 8,974 (5,748–12,261) years for the most recent common ancestor of C1d3, in agreement with the initial peopling of the geographic region. No individuals belonging to the defined lineage were found outside of Uruguay, which raises questions regarding the mobility of the prehistoric inhabitants of the country. Moreover, the present study shows the continuity of Native lineages over at least 6,000 years. PMID:26509686

  16. Combustion synthesis as a novel method for production of 1-D SiC nanostructures.

    PubMed

    Huczko, Andrzej; Bystrzejewski, Michał; Lange, Hubert; Fabianowska, Agnieszka; Cudziło, Stanisław; Panas, Andrzej; Szala, Mateusz

    2005-09-01

    1-D nanostructures of cubic phase silicon carbide (beta-SiC) were efficiently produced by combustion synthesis of mixtures containing Si-containing compounds and halocarbons in a calorimetric bomb. The influence of the operating parameters on 1-D SiC formation yield was studied. The heat release, the heating rate, and the chamber pressure increase were monitored during the process. The composition and structural features of the products were characterized by elemental analysis, X-ray diffraction, differential thermal analysis/ thermogravimetric technique, Raman spectroscopy, scanning and transmission electron microscopy, and energy-dispersive X-ray spectrometry. This self-induced growth process can produce SiC nanofibers and nanotubes ca. 20-100 nm in diameter with the aspect ratio higher than 1000. Bulk scale Raman studies showed the product to be comprised of mostly cubic polytype of SiC and that finite size effects are present. We believe that the nucleation mechanism involving radical gaseous species is responsible for 1-D nanostructures growth. The present study has enlarged the family of nanofibers and nanotubes available and offers a possible, new general route to 1-D crystalline materials. PMID:16853065

  17. Toward Structural Correctness: Aquatolide and the Importance of 1D Proton NMR FID Archiving.

    PubMed

    Pauli, Guido F; Niemitz, Matthias; Bisson, Jonathan; Lodewyk, Michael W; Soldi, Cristian; Shaw, Jared T; Tantillo, Dean J; Saya, Jordy M; Vos, Klaas; Kleinnijenhuis, Roel A; Hiemstra, Henk; Chen, Shao-Nong; McAlpine, James B; Lankin, David C; Friesen, J Brent

    2016-02-01

    The revision of the structure of the sesquiterpene aquatolide from a bicyclo[2.2.0]hexane to a bicyclo[2.1.1]hexane structure using compelling NMR data, X-ray crystallography, and the recent confirmation via full synthesis exemplify that the achievement of "structural correctness" depends on the completeness of the experimental evidence. Archived FIDs and newly acquired aquatolide spectra demonstrate that archiving and rigorous interpretation of 1D (1)H NMR data may enhance the reproducibility of (bio)chemical research and curb the growing trend of structural misassignments. Despite being the most accessible NMR experiment, 1D (1)H spectra encode a wealth of information about bonds and molecular geometry that may be fully mined by (1)H iterative full spin analysis (HiFSA). Fully characterized 1D (1)H spectra are unideterminant for a given structure. The corresponding FIDs may be readily submitted with publications and collected in databases. Proton NMR spectra are indispensable for structural characterization even in conjunction with 2D data. Quantum interaction and linkage tables (QuILTs) are introduced for a more intuitive visualization of 1D J-coupling relationships, NOESY correlations, and heteronuclear experiments. Overall, this study represents a significant contribution to best practices in NMR-based structural analysis and dereplication. PMID:26812443

  18. Energy transformation of plasmonic photocatalytic oxidation on 1D quantum well of platinum thin film

    NASA Astrophysics Data System (ADS)

    Huang, Hung Ji; Liu, Bo-Heng

    2015-12-01

    The energy transformation of vertical incident light into energy for a chemical reaction is demonstrated in the endothermic oxidation of ammonium ions in a spinning disk reactor. The plasmonic enhancement on photocatalytic reaction demonstrated the generation of quantum hot charge on 1D quantum well of platinum thin film.

  19. α(1D)-Adrenergic receptors constitutive activity and reduced expression at the plasma membrane.

    PubMed

    García-Sáinz, J Adolfo; Romero-Ávila, M Teresa; Medina, Luz Del Carmen

    2010-01-01

    Adrenergic receptors are a heterogeneous family of the G protein-coupled receptors that mediate the actions of adrenaline and noradrenaline. Adrenergic receptors comprise three subfamilies (α(1), α(2), and β, with three members each) and the α(1D)-adrenergic receptor is one of the members of the α(1) subfamily with some interesting traits. The α(1D)-adrenergic receptor is difficult to express, seems predominantly located intracellularly, and exhibits constitutive activity. In this chapter, we will describe in detail the conditions and procedures used to determine changes in intracellular free calcium concentration which has been instrumental to define the constitutive activity of these receptors. Taking advantage of the fact that truncation of the first 79 amino acids of α(1D)-adrenergic receptors markedly increased their membrane expression, we were able to show that constitutive activity is present in receptors truncated at the amino and carboxyl termini, which indicates that such domains are dispensable for this action. Constitutive activity could be observed in cells expressing either the rat or human α(1D)-adrenergic receptor orthologs. Such constitutive activity has been observed in native rat arteries and we will discuss the possible functional implications that it might have in the regulation of blood pressure.

  20. Quasi 1-D Study of Pulse Detonation Rocket Engine Blowdown Gasdynamics and Performance

    NASA Technical Reports Server (NTRS)

    Morris, Christopher I.

    2002-01-01

    Pulse detonation rocket engines (PDREs) offer potential performance improvements over conventional designs, but represent a challenging modeling task. A quasi 1-D, finite-rate chemistry CFD model for a PDRE is described and implemented. A parametric study of the effect of blowdown pressure ratio on the performance of several different PDRE nozzle configurations is reported.

  1. Recent developments in testing techniques for elastic mechanical properties of 1-D nanomaterials.

    PubMed

    Wang, Weidong; Li, Shuai; Zhang, Hongti; Lu, Yang

    2015-01-01

    One-dimensional (1-D) nanomaterials exhibit great potentials in their applications to functional materials, nano-devices and systems owing to their excellent properties. In the past decade, considerable studies have been done, with new patents being developed, on these 1-D building blocks for for their mechanical properties, especially elastic properties, which provide a solid foundation for the design of nanoelectromechanical systems (NEMS) and predictions of reliability and longevity for their devices. This paper reviews some of the recent investigations on techniques as well as patents available for the quantitative characterization of the elastic behaviors of various 1-D nanomaterials, with particular focus on on-chip testing system. The review begins with an overview of major testing methods for 1-D nanostructures' elastic properties, including nanoindentation testing, AFM (atomic force microscopy) testing, in situ SEM (scanning electron microscopy) testing, in situ TEM (transmission electron microscopy) testing and the testing system on the basis of MEMS (micro-electro-mechanical systems) technology, followed by advantages and challenges of each testing approach. This review also focuses on the MEMS-based testing apparatus, which can be actuated and measured inside SEM and TEM with ease, allowing users to highly magnify the continuous images of the specimen while measuring load electronically and independently. The combination of on-chip technologies and the in situ electron microscopy is expected to be a potential testing technique for nanomechanics. Finally, details are presented on the key challenges and possible solutions in the implementation of the testing techniques referred above.

  2. Millimeter and Submillimeter Studies of O(^1D) Insertion Reactions to Form Molecules of Astrophysical Interest

    NASA Astrophysics Data System (ADS)

    Hays, Brian; Wehres, Nadine; Deprince, Bridget Alligood; Roy, Althea A. M.; Laas, Jacob; Widicus Weaver, Susanna L.

    2015-06-01

    While both the number of detected interstellar molecules and their chemical complexity continue to increase, understanding of the processes leading to their formation is lacking. Our research group combines laboratory spectroscopy, observational astronomy, and astrochemical modeling for an interdisciplinary examination of the chemistry of star and planet formation. This talk will focus on our laboratory studies of O(^1D) insertion reactions with organic molecules to produce molecules of astrophysical interest. By employing these reactions in a supersonic expansion, we are able to produce interstellar organic reaction intermediates that are unstable under terrestrial conditions; we then probe the products using millimeter and submillimeter spectroscopy. We benchmarked this setup using the well-studied O(^1D) + methane reaction to form methanol. After optimizing methanol production, we moved on to study the O(^1D) + ethylene reaction to form vinyl alcohol (CH_2CHOH), and the O(^1D) + methyl amine reaction to form aminomethanol (NH_2CH_2OH). Vinyl alcohol measurements have now been extended up to 450 GHz, and the associated spectral analysis is complete. A possible detection of aminomethanol has also been made, and continued spectral studies and analysis are underway. We will present the results from these experiments and discuss future applications of these molecular and spectroscopic techniques.

  3. Build up An Operational Flood Simulation from Existing 1D Channel Flow Works

    NASA Astrophysics Data System (ADS)

    Chang, Che-Hao; Hsu, Chih-Tsung; Wu, Shiang-Jen; Lien, Ho-Cheng; Shen, Jhih-Cyuan; Chung, Ming-Ko

    2016-04-01

    Several 2D flood simulations will be developed for urban area in recent years in Taiwan. Original ideas focus on the static flood maps produced by the 2D flood simulation with respect to design events, which could be useful no matter for planning or disaster awareness. However, an extra bonus is expected to see if we can reuse the 2D flood simulation framework for operational use or not. Such a project goal inspire us to setup a standard operation procedure before any progress from existing 1D channel flow works. 3 key issues are taken into account in the SOP: 1. High Resolution Terrain: A 1m resolution digital terrain model (DTM) is considered as a reference. The Channels and structures should be setup in 1D channel flow works if we can identify under such high resolution. One should examine the existing 1D channel flow works consistent with the DTM or not. 2. Meteo Stations Referenced: Real time precipitation would be send to referenced location in RR models during an operational forecast. Existing 1D channels flow works are usually specifically for design events which are not necessarily equipped with such references. 3. Time Consuming: A full scale 2D flood simulation needs a lot of computation resources. A solution should be derived within practical time limits. Under the above consideration, some impacts and procedures will be analyzed and developed to setup the SOP for further model modification.

  4. Plasma as a tool for growth of 1D and 2D nanomaterials and their conversions

    NASA Astrophysics Data System (ADS)

    Cvelbar, Uros

    2015-09-01

    The growth of 1D and 2D nanostructures in low pressure oxygen plasma is presented with the special stress on metal-oxide nanowires and their deterministic growth mechanisms. Since the resulting nanostructures not always have required properties for applications their modifications are required. Therefore their conversions into different oxides or sulphites/nitrides are required with either molecules, atoms, electrons or photons.

  5. Observing the 1D-3D Crossover in a Spin-Imbalanced Fermi Gas

    NASA Astrophysics Data System (ADS)

    Revelle, Melissa C.; Fry, Jacob A.; Olsen, Ben A.; Hulet, Randall G.

    2016-05-01

    Trapped two-component Fermi gases phase separate into superfluid and normal phases when their spin populations are imbalanced. In 3D, a balanced superfluid core is surrounded by shells of partially polarized and normal phases, while in 1D, the balanced superfluid occupies the low density wings. We explored the crossover from 3D to 1D using a two-spin component ultracold atomic gas of 6 Li prepared in the lowest two hyperfine sublevels, where the interactions are tuned by a Feshbach resonance. The atoms are confined to 1D tubes where the tunneling rate t between tubes is varied by changing the depth of a 2D optical lattice. We observe the transition from 1D to 3D-like phase separation by varying t and interaction strength which changes the pair binding energy ɛB. We find a universal scaling of the dimensional crossover with t /ɛB , in agreement with previous theory. The crossover region is believed to be the most promising to find the exotic FFLO superfluid phase. Supported by the NSF and the Welch Foundation.

  6. Behavioral Responses in Animal Model of Congenital Muscular Dystrophy 1D.

    PubMed

    Comim, Clarissa M; Schactae, Aryadnne L; Soares, Jaime A; Ventura, Letícia; Freiberger, Viviane; Mina, Francielle; Dominguini, Diogo; Vainzof, Mariz; Quevedo, João

    2016-01-01

    Congenital muscular dystrophies 1D (CMD1D) present a mutation on the LARGE gene and are characterized by an abnormal glycosylation of α-dystroglycan (α-DG), strongly implicated as having a causative role in the development of central nervous system abnormalities such as cognitive impairment seen in patients. However, in the animal model of CMD1D, the brain involvement remains unclear. Therefore, the objective of this study is to evaluate the cognitive involvement in the Large(myd) mice. To this aim, we used adult homozygous, heterozygous, and wild-type mice. The mice underwent six behavioral tasks: habituation to an open field, step-down inhibitory avoidance, continuous multiple trials step-down inhibitory avoidance task, object recognition, elevated plus-maze, and forced swimming test. It was observed that Large(myd) individuals presented deficits on the habituation to the open field, step down inhibitory avoidance, continuous multiple-trials step-down inhibitory avoidance, object recognition, and forced swimming. This study shows the first evidence that abnormal glycosylation of α-DG may be affecting memory storage and restoring process in an animal model of CMD1D.

  7. Formation of 1D adsorbed water structures on CaO(001)

    NASA Astrophysics Data System (ADS)

    Zhao, Xunhua; Bhattacharya, Saswata; Ghiringhelli, Luca M.; Levchenko, Sergey V.; Scheffler, Matthias

    2015-03-01

    Understanding the interaction of water with oxide surfaces is of fundamental importance for basic and engineering sciences. Recently, a spontaneous formation of one-dimensional (1D) adsorbed water structures have been observed on CaO(001). Interestingly, at other alkaline earth metal oxides, in particular MgO(001) and SrO(001), such structures have not been found experimentally. We calculate the relative stability of adsorbed water structures on the three oxides using density-functional theory combined with the ab initio atomistic thermodynamics. Low-energy structures at different coverages are obtained with a first-principles genetic algorithm. Finite-temperature vibrational spectra are calculated using ab initio molecular dynamics. We find a range of (T, p) conditions where 1D structures are thermodynamically stable on CaO(001). The orientation and vibrational spectra of the 1D structures are in agreement with the experiments. The formation of the 1D structures is found to be actuated by a symmetry breaking in the adsorbed water tetramer, as well as by a balance between water-water and water-substrate interactions, determined by the lattice constant of the oxide.

  8. CD1d-restricted peripheral T cell lymphoma in mice and humans.

    PubMed

    Bachy, Emmanuel; Urb, Mirjam; Chandra, Shilpi; Robinot, Rémy; Bricard, Gabriel; de Bernard, Simon; Traverse-Glehen, Alexandra; Gazzo, Sophie; Blond, Olivier; Khurana, Archana; Baseggio, Lucile; Heavican, Tayla; Ffrench, Martine; Crispatzu, Giuliano; Mondière, Paul; Schrader, Alexandra; Taillardet, Morgan; Thaunat, Olivier; Martin, Nadine; Dalle, Stéphane; Le Garff-Tavernier, Magali; Salles, Gilles; Lachuer, Joel; Hermine, Olivier; Asnafi, Vahid; Roussel, Mikael; Lamy, Thierry; Herling, Marco; Iqbal, Javeed; Buffat, Laurent; Marche, Patrice N; Gaulard, Philippe; Kronenberg, Mitchell; Defrance, Thierry; Genestier, Laurent

    2016-05-01

    Peripheral T cell lymphomas (PTCLs) are a heterogeneous entity of neoplasms with poor prognosis, lack of effective therapies, and a largely unknown pathophysiology. Identifying the mechanism of lymphomagenesis and cell-of-origin from which PTCLs arise is crucial for the development of efficient treatment strategies. In addition to the well-described thymic lymphomas, we found that p53-deficient mice also developed mature PTCLs that did not originate from conventional T cells but from CD1d-restricted NKT cells. PTCLs showed phenotypic features of activated NKT cells, such as PD-1 up-regulation and loss of NK1.1 expression. Injections of heat-killed Streptococcus pneumonia, known to express glycolipid antigens activating NKT cells, increased the incidence of these PTCLs, whereas Escherichia coli injection did not. Gene expression profile analyses indicated a significant down-regulation of genes in the TCR signaling pathway in PTCL, a common feature of chronically activated T cells. Targeting TCR signaling pathway in lymphoma cells, either with cyclosporine A or anti-CD1d blocking antibody, prolonged mice survival. Importantly, we identified human CD1d-restricted lymphoma cells within Vδ1 TCR-expressing PTCL. These results define a new subtype of PTCL and pave the way for the development of blocking anti-CD1d antibody for therapeutic purposes in humans. PMID:27069116

  9. Toward Structural Correctness: Aquatolide and the Importance of 1D Proton NMR FID Archiving

    PubMed Central

    2016-01-01

    The revision of the structure of the sesquiterpene aquatolide from a bicyclo[2.2.0]hexane to a bicyclo[2.1.1]hexane structure using compelling NMR data, X-ray crystallography, and the recent confirmation via full synthesis exemplify that the achievement of “structural correctness” depends on the completeness of the experimental evidence. Archived FIDs and newly acquired aquatolide spectra demonstrate that archiving and rigorous interpretation of 1D 1H NMR data may enhance the reproducibility of (bio)chemical research and curb the growing trend of structural misassignments. Despite being the most accessible NMR experiment, 1D 1H spectra encode a wealth of information about bonds and molecular geometry that may be fully mined by 1H iterative full spin analysis (HiFSA). Fully characterized 1D 1H spectra are unideterminant for a given structure. The corresponding FIDs may be readily submitted with publications and collected in databases. Proton NMR spectra are indispensable for structural characterization even in conjunction with 2D data. Quantum interaction and linkage tables (QuILTs) are introduced for a more intuitive visualization of 1D J-coupling relationships, NOESY correlations, and heteronuclear experiments. Overall, this study represents a significant contribution to best practices in NMR-based structural analysis and dereplication. PMID:26812443

  10. A South American Prehistoric Mitogenome: Context, Continuity, and the Origin of Haplogroup C1d.

    PubMed

    Sans, Mónica; Figueiro, Gonzalo; Hughes, Cris E; Lindo, John; Hidalgo, Pedro C; Malhi, Ripan S

    2015-01-01

    Based on mitochondrial DNA (mtDNA), it has been estimated that at least 15 founder haplogroups peopled the Americas. Subhaplogroup C1d3 was defined based on the mitogenome of a living individual from Uruguay that carried a lineage previously identified in hypervariable region I sequences from ancient and modern Uruguayan individuals. When complete mitogenomes were studied, additional substitutions were found in the coding region of the mitochondrial genome. Using a complete ancient mitogenome and three modern mitogenomes, we aim to clarify the ancestral state of subhaplogroup C1d3 and to better understand the peopling of the region of the Río de la Plata basin, as well as of the builders of the mounds from which the ancient individuals were recovered. The ancient mitogenome, belonging to a female dated to 1,610±46 years before present, was identical to the mitogenome of one of the modern individuals. All individuals share the mutations defining subhaplogroup C1d3. We estimated an age of 8,974 (5,748-12,261) years for the most recent common ancestor of C1d3, in agreement with the initial peopling of the geographic region. No individuals belonging to the defined lineage were found outside of Uruguay, which raises questions regarding the mobility of the prehistoric inhabitants of the country. Moreover, the present study shows the continuity of Native lineages over at least 6,000 years. PMID:26509686

  11. Laser Crystal

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Lightning Optical Corporation, under an SBIR (Small Business Innovative Research) agreement with Langley Research Center, manufactures oxide and fluoride laser gain crystals, as well as various nonlinear materials. The ultimate result of this research program is the commercial availability in the marketplace of a reliable source of high-quality, damage resistant laser material, primarily for diode-pumping applications.

  12. Comparing Crystals

    ERIC Educational Resources Information Center

    Sharp, Janet; Hoiberg, Karen; Chumbley, Scott

    2003-01-01

    This standard lesson on identifying salt and sugar crystals expands into an opportunity for students to develop their observation, questioning, and modeling skills. Although sugar and salt may look similar, students discovered that they looked very different under a magnifying glass and behaved differently when dissolved in water. In addition,…

  13. Optical Crystals

    ERIC Educational Resources Information Center

    Bergsten, Ronald

    1974-01-01

    Discusses the production and structure of a sequence of optical crystals which can serve as one-, two-, and three-dimensional diffraction plates to illustrate diffraction patterns by using light rather than x-rays or particles. Applications to qualitative presentations of Laue theory at the secondary and college levels are recommended. (CC)

  14. Therapeutic Crystals

    ERIC Educational Resources Information Center

    Bond, Charles S.

    2014-01-01

    Some readers might not fully know what the difference is between crystallography, and the "new age" practice of dangling crystals around the body to capitalise on their healing energy. The latter is often considered to be superstition, while ironically, the former has actually resulted in real rationally-based healing of human diseases…

  15. A new EEG measure using the 1D cluster variation method

    NASA Astrophysics Data System (ADS)

    Maren, Alianna J.; Szu, Harold H.

    2015-05-01

    A new information measure, drawing on the 1-D Cluster Variation Method (CVM), describes local pattern distributions (nearest-neighbor and next-nearest neighbor) in a binary 1-D vector in terms of a single interaction enthalpy parameter h for the specific case where the fractions of elements in each of two states are the same (x1=x2=0.5). An example application of this method would be for EEG interpretation in Brain-Computer Interfaces (BCIs), especially in the frontier of invariant biometrics based on distinctive and invariant individual responses to stimuli containing an image of a person with whom there is a strong affiliative response (e.g., to a person's grandmother). This measure is obtained by mapping EEG observed configuration variables (z1, z2, z3 for next-nearest neighbor triplets) to h using the analytic function giving h in terms of these variables at equilibrium. This mapping results in a small phase space region of resulting h values, which characterizes local pattern distributions in the source data. The 1-D vector with equal fractions of units in each of the two states can be obtained using the method for transforming natural images into a binarized equi-probability ensemble (Saremi & Sejnowski, 2014; Stephens et al., 2013). An intrinsically 2-D data configuration can be mapped to 1-D using the 1-D Peano-Hilbert space-filling curve, which has demonstrated a 20 dB lower baseline using the method compared with other approaches (cf. SPIE ICA etc. by Hsu & Szu, 2014). This CVM-based method has multiple potential applications; one near-term one is optimizing classification of the EEG signals from a COTS 1-D BCI baseball hat. This can result in a convenient 3-D lab-tethered EEG, configured in a 1-D CVM equiprobable binary vector, and potentially useful for Smartphone wireless display. Longer-range applications include interpreting neural assembly activations via high-density implanted soft, cellular-scale electrodes.

  16. Experimental use of TRMM precipitation radar observations in 1D+4D-Var assimilation

    NASA Astrophysics Data System (ADS)

    Benedetti, Angela; Lopez, Philippe; Bauer, Peter; Moreau, Emmanuel

    2005-07-01

    This paper presents a new application of the Tropical Rainfall Measuring Mission (TRMM) precipitation radar (PR) observations for indirect assimilation into the European Centre for Medium-Range Weather Forecasts (ECMWF) model. The PR reflectivities are first processed using a one-dimensional variational (1D-Var) method to adjust model temperature and specific humidity. The retrieved Total Column Water Vapour (TCWV) is then assimilated into the operational four-dimensional variational (4D-Var) system. The applicability of the 1D+4D-Var approach to the radar observations is discussed in detail.Several case studies were run to assess the feasibility and the effectiveness of assimilating PR reflectivities with a 1D-Var approach. Results show good behaviour of the 1D-Var system in terms of convergence and stability. Its performance in terms of retrieved TCWV is comparable to that of other 1D-Vars which make use of TRMM Microwave Imager (TMI) observations. When the 1D-Var TCWV pseudo-observations are input into the 4D-Var system, a positive impact is shown in the analysis and the subsequent forecasts, both on moisture-related fields and also on winds and surface pressure. The quality of the forecast is verified using track observations for the tropical cyclones. The track forecasts from the experiments which include 1D-Var TCWV are generally closer to the observed track than a control run. Despite their much smaller spatial coverage than TMI observations, it is found that the PR data have a comparable impact, provided the satellite samples a meaningful portion of the storm, possibly its centre. This is possibly due to the fact that TCWV increments from PR and from TMI brightness temperature have similar magnitudes.These results show that active sensor data can provide indirect yet useful information on the moisture field and that this information can effectively be assimilated to improve the analysis and the forecast of tropical disturbances. Although this is a sub

  17. Ascites Specific Inhibition of CD1d-Mediated Activation of NKT cells

    PubMed Central

    Webb, Tonya J.; Giuntoli, Robert L.; Rogers, Ophelia; Schneck, Jonathan; Oelke, Mathias

    2009-01-01

    Purpose Natural killer T (NKT) cells recognize lipid antigen presented by CD1 molecules. NKT cells can both directly, through cytotoxicity, and indirectly, through activation of other effector cells, mediate anti-tumor immunity. However, it has been shown that tumor associated lipids are frequently shed into the tumor microenvironment, which can mediate immunosuppressive activity. Given that ovarian cancer associated ascites has been reported to have increased levels of gangliosides, we examined the effect of tumor associated and other ascites on CD1d-mediated antigen presentation to NKT cells. Experimental Design To investigate the effects of ascites on NKT cell activation, we pretreated CD1d-expressing cells with the ascites and measured their ability to stimulate cytokine production in NKT cells. To determine whether antigen processing or editing was necessary, CD1d-Ig-based artificial Antigen Presenting Cells (aAPC) were also incubated with ascites. In addition, to examine specificity, we analyzed whether ascites fluid could influence the activation of classical CD8+ T cells. Results Pretreatment of CD1d-expressing cells with ascites from the majority of patients inhibited the cells’ ability to stimulate/activate NKT cells in a dose-dependent manner. Ascites treatment also partially blocked the ability of α-GalCer loaded CD1d-Ig-based artificial Antigen Presenting Cells (aAPC) to activate NKT cells. In addition, our data demonstrate that treatment with ascites does not inhibit HLA-A2 mediated activation of classical CD8+ T cells. Conclusions Together, these data suggest that ovarian and other cancers may have developed immune evasion mechanisms specifically targeting the CD1/NKT cell system. PMID:19047090

  18. The D1-D2 region of the large subunit ribosomal DNA as barcode for ciliates.

    PubMed

    Stoeck, T; Przybos, E; Dunthorn, M

    2014-05-01

    Ciliates are a major evolutionary lineage within the alveolates, which are distributed in nearly all habitats on our planet and are an essential component for ecosystem function, processes and stability. Accurate identification of these unicellular eukaryotes through, for example, microscopy or mating type reactions is reserved to few specialists. To satisfy the demand for a DNA barcode for ciliates, which meets the standard criteria for DNA barcodes defined by the Consortium for the Barcode of Life (CBOL), we here evaluated the D1-D2 region of the ribosomal DNA large subunit (LSU-rDNA). Primer universality for the phylum Ciliophora was tested in silico with available database sequences as well as in the laboratory with 73 ciliate species, which represented nine of 12 ciliate classes. Primers tested in this study were successful for all tested classes. To test the ability of the D1-D2 region to resolve conspecific and congeneric sequence divergence, 63 Paramecium strains were sampled from 24 mating species. The average conspecific D1-D2 variation was 0.18%, whereas congeneric sequence divergence averaged 4.83%. In pairwise genetic distance analyses, we identified a D1-D2 sequence divergence of <0.6% as an ideal threshold to discriminate Paramecium species. Using this definition, only 3.8% of all conspecific and 3.9% of all congeneric sequence comparisons had the potential of false assignments. Neighbour-joining analyses inferred monophyly for all taxa but for two Paramecium octaurelia strains. Here, we present a protocol for easy DNA amplification of single cells and voucher deposition. In conclusion, the presented data pinpoint the D1-D2 region as an excellent candidate for an official CBOL barcode for ciliated protists.

  19. What causes the large extensions of red supergiant atmospheres?. Comparisons of interferometric observations with 1D hydrostatic, 3D convection, and 1D pulsating model atmospheres

    NASA Astrophysics Data System (ADS)

    Arroyo-Torres, B.; Wittkowski, M.; Chiavassa, A.; Scholz, M.; Freytag, B.; Marcaide, J. M.; Hauschildt, P. H.; Wood, P. R.; Abellan, F. J.

    2015-03-01

    Aims: This research has two main goals. First, we present the atmospheric structure and the fundamental parameters of three red supergiants (RSGs), increasing the sample of RSGs observed by near-infrared spectro-interferometry. Additionally, we test possible mechanisms that may explain the large observed atmospheric extensions of RSGs. Methods: We carried out spectro-interferometric observations of the RSGs V602 Car, HD 95687, and HD 183589 in the near-infrared K-band (1.92-2.47 μm) with the VLTI/AMBER instrument at medium spectral resolution (R ~ 1500). To categorize and comprehend the extended atmospheres, we compared our observational results to predictions by available hydrostatic PHOENIX, available 3D convection, and new 1D self-excited pulsation models of RSGs. Results: Our near-infrared flux spectra of V602 Car, HD 95687, and HD 183589 are well reproduced by the PHOENIX model atmospheres. The continuum visibility values are consistent with a limb-darkened disk as predicted by the PHOENIX models, allowing us to determine the angular diameter and the fundamental parameters of our sources. Nonetheless, in the case of V602 Car and HD 95686, the PHOENIX model visibilities do not predict the large observed extensions of molecular layers, most remarkably in the CO bands. Likewise, the 3D convection models and the 1D pulsation models with typical parameters of RSGs lead to compact atmospheric structures as well, which are similar to the structure of the hydrostatic PHOENIX models. They can also not explain the observed decreases in the visibilities and thus the large atmospheric molecular extensions. The full sample of our RSGs indicates increasing observed atmospheric extensions with increasing luminosity and decreasing surface gravity, and no correlation with effective temperature or variability amplitude. Conclusions: The location of our RSG sources in the Hertzsprung-Russell diagram is confirmed to be consistent with the red limits of recent evolutionary tracks

  20. Deletion of the Rab GAP Tbc1d1 modifies glucose, lipid, and energy homeostasis in mice.

    PubMed

    Hargett, Stefan R; Walker, Natalie N; Hussain, Syed S; Hoehn, Kyle L; Keller, Susanna R

    2015-08-01

    Tbc1d1 is a Rab GTPase-activating protein (GAP) implicated in regulating intracellular retention and cell surface localization of the glucose transporter GLUT4 and thus glucose uptake in a phosphorylation-dependent manner. Tbc1d1 is most abundant in skeletal muscle but is expressed at varying levels among different skeletal muscles. Previous studies with male Tbc1d1-deficient (Tbc1d1(-/-)) mice on standard and high-fat diets established a role for Tbc1d1 in glucose, lipid, and energy homeostasis. Here we describe similar, but also additional abnormalities in male and female Tbc1d1(-/-) mice. We corroborate that Tbc1d1 loss leads to skeletal muscle-specific and skeletal muscle type-dependent abnormalities in GLUT4 expression and glucose uptake in female and male mice. Using subcellular fractionation, we show that Tbc1d1 controls basal intracellular GLUT4 retention in large skeletal muscles. However, cell surface labeling of extensor digitorum longus muscle indicates that Tbc1d1 does not regulate basal GLUT4 cell surface exposure as previously suggested. Consistent with earlier observations, female and male Tbc1d1(-/-) mice demonstrate increased energy expenditure and skeletal muscle fatty acid oxidation. Interestingly, we observe sex-dependent differences in in vivo phenotypes. Female, but not male, Tbc1d1(-/-) mice have decreased body weight and impaired glucose and insulin tolerance, but only male Tbc1d1(-/-) mice show increased lipid clearance after oil gavage. We surmise that similar changes at the tissue level cause differences in whole-body metabolism between male and female Tbc1d1(-/-) mice and between male Tbc1d1(-/-) mice in different studies due to variations in body composition and nutrient handling.

  1. Deletion of the Rab GAP Tbc1d1 modifies glucose, lipid, and energy homeostasis in mice.

    PubMed

    Hargett, Stefan R; Walker, Natalie N; Hussain, Syed S; Hoehn, Kyle L; Keller, Susanna R

    2015-08-01

    Tbc1d1 is a Rab GTPase-activating protein (GAP) implicated in regulating intracellular retention and cell surface localization of the glucose transporter GLUT4 and thus glucose uptake in a phosphorylation-dependent manner. Tbc1d1 is most abundant in skeletal muscle but is expressed at varying levels among different skeletal muscles. Previous studies with male Tbc1d1-deficient (Tbc1d1(-/-)) mice on standard and high-fat diets established a role for Tbc1d1 in glucose, lipid, and energy homeostasis. Here we describe similar, but also additional abnormalities in male and female Tbc1d1(-/-) mice. We corroborate that Tbc1d1 loss leads to skeletal muscle-specific and skeletal muscle type-dependent abnormalities in GLUT4 expression and glucose uptake in female and male mice. Using subcellular fractionation, we show that Tbc1d1 controls basal intracellular GLUT4 retention in large skeletal muscles. However, cell surface labeling of extensor digitorum longus muscle indicates that Tbc1d1 does not regulate basal GLUT4 cell surface exposure as previously suggested. Consistent with earlier observations, female and male Tbc1d1(-/-) mice demonstrate increased energy expenditure and skeletal muscle fatty acid oxidation. Interestingly, we observe sex-dependent differences in in vivo phenotypes. Female, but not male, Tbc1d1(-/-) mice have decreased body weight and impaired glucose and insulin tolerance, but only male Tbc1d1(-/-) mice show increased lipid clearance after oil gavage. We surmise that similar changes at the tissue level cause differences in whole-body metabolism between male and female Tbc1d1(-/-) mice and between male Tbc1d1(-/-) mice in different studies due to variations in body composition and nutrient handling. PMID:26015432

  2. Modeling of impurity spectroscopy in the divertor and SOL of DIII-D using the 1D multifluid model NEWT1D

    SciTech Connect

    West, W.P.; Evans, T.E.; Brooks, N.H.

    1996-10-01

    NEWT1D, a one dimensional multifluid model of the scrape-off layer and divertor plasma, has been used to model the plasma including the distribution of carbon ionization states in the SOL and divertor of ELMing H-mode at two injected power levels in DIII-D. Comparison of the code predictions to the measured divertor and scrape-off layer (SOL) plasma density and temperature shows good agreement. Comparison of the predicted line emissions to the spectroscopic data suggests that physically sputtered carbon from the strike point is not transported up the flux tube; a distributed source of carbon a few centimeters up the flux tube is required to achieve reasonable agreement.

  3. Amplified Emission and Field-Effect Transistor Characteristics of One-Dimensionally Structured 2,5-Bis(4-biphenylyl)thiophene Crystals.

    PubMed

    Hashimoto, Kazumasa; Sasaki, Fumio; Hotta, Shu; Yanagi, Hisao

    2016-04-01

    One-dimensional (1D) structures of 2,5-bis(4-biphenylyl)thiophene (BP1T) crystals are fabricated for light amplification and field-effect transistor (FET) measurements. A strip-shaped 1D structure (10 µm width) made by photolitography of a vapor-deposited polycrystalline film shows amplified spontaneous emission and lasing oscillations under optical pumping. An FET fabricated with this 1D structure exhibits hole-conduction with a mobility of µh = 8.0 x 10(-3) cm2/Vs. Another 1 D-structured FET is fabricated with epitaxially grown needle-like crystals of BP1T. This needle-crystal FET exhibits higher mobility of µh = 0.34 cm2/Vs. This improved hole mobility is attributed to the single-crystal channel of epitaxial needles while the grain boudaries in the polycrystalline 1 D-structure decrease the carrier transport. PMID:27451604

  4. O(1D) kinetic study of key ozone depleting substances and greenhouse gases.

    PubMed

    Baasandorj, Munkhbayar; Fleming, Eric L; Jackman, Charles H; Burkholder, James B

    2013-03-28

    A key stratospheric loss process for ozone depleting substances (ODSs) and greenhouse gases (GHGs) is reaction with the O((1)D) atom. In this study, rate coefficients, k, for the O((1)D) atom reaction were measured for the following key halocarbons: chlorofluorocarbons (CFCs) CFCl3 (CFC-11), CF2Cl2 (CFC-12), CFCl2CF2Cl (CFC-113), CF2ClCF2Cl (CFC-114), CF3CF2Cl (CFC-115); hydrochlorofluorocarbons (HCFCs) CHF2Cl (HCFC-22), CH3CClF2 (HCFC-142b); and hydrofluorocarbons (HFCs) CHF3 (HFC-23), CHF2CF3 (HFC-125), CH3CF3 (HFC-143a), and CF3CHFCF3 (HFC-227ea). Total rate coefficients, kT, corresponding to the loss of the O((1)D) atom, were measured over the temperature range 217-373 K using a competitive reactive technique. kT values for the CFC and HCFC reactions were >1 × 10(-10) cm(3) molecule(-1) s(-1), except for CFC-115, and the rate coefficients for the HFCs were in the range (0.095-0.72) × 10(-10) cm(3) molecule(-1) s(-1). Rate coefficients for the CFC-12, CFC-114, CFC-115, HFC-23, HFC-125, HFC-143a, and HFC-227ea reactions were observed to have a weak negative temperature dependence, E/R ≈ -25 K. Reactive rate coefficients, kR, corresponding to the loss of the halocarbon, were measured for CFC-11, CFC-115, HCFC-22, HCFC-142b, HFC-23, HFC-125, HFC-143a, and HFC-227ea using a relative rate technique. The reactive branching ratio obtained was dependent on the composition of the halocarbon and the trend in O((1)D) reactivity with the extent of hydrogen and chlorine substitution is discussed. The present results are critically compared with previously reported kinetic data and the discrepancies are discussed. 2D atmospheric model calculations were used to evaluate the local and global annually averaged atmospheric lifetimes of the halocarbons and the contribution of O((1)D) chemistry to their atmospheric loss. The O((1)D) reaction was found to be a major global loss process for CFC-114 and CFC-115 and a secondary global loss process for the other molecules included

  5. Transient Plasma Photonic Crystals for High-Power Lasers.

    PubMed

    Lehmann, G; Spatschek, K H

    2016-06-01

    A new type of transient photonic crystals for high-power lasers is presented. The crystal is produced by counterpropagating laser beams in plasma. Trapped electrons and electrically forced ions generate a strong density grating. The lifetime of the transient photonic crystal is determined by the ballistic motion of ions. The robustness of the photonic crystal allows one to manipulate high-intensity laser pulses. The scheme of the crystal is analyzed here by 1D Vlasov simulations. Reflection or transmission of high-power laser pulses are predicted by particle-in-cell simulations. It is shown that a transient plasma photonic crystal may act as a tunable mirror for intense laser pulses. Generalizations to 2D and 3D configurations are possible. PMID:27314721

  6. Transient Plasma Photonic Crystals for High-Power Lasers

    NASA Astrophysics Data System (ADS)

    Lehmann, G.; Spatschek, K. H.

    2016-06-01

    A new type of transient photonic crystals for high-power lasers is presented. The crystal is produced by counterpropagating laser beams in plasma. Trapped electrons and electrically forced ions generate a strong density grating. The lifetime of the transient photonic crystal is determined by the ballistic motion of ions. The robustness of the photonic crystal allows one to manipulate high-intensity laser pulses. The scheme of the crystal is analyzed here by 1D Vlasov simulations. Reflection or transmission of high-power laser pulses are predicted by particle-in-cell simulations. It is shown that a transient plasma photonic crystal may act as a tunable mirror for intense laser pulses. Generalizations to 2D and 3D configurations are possible.

  7. TCTEX1D4 Interactome in Human Testis: Unraveling the Function of Dynein Light Chain in Spermatozoa

    PubMed Central

    Freitas, Maria João; Korrodi-Gregório, Luís; Morais-Santos, Filipa; da Cruz e Silva, Edgar

    2014-01-01

    Abstract Studies were designed to identify the TCTEX1D4 interactome in human testis, with the purpose of unraveling putative protein complexes essential to male reproduction and thus novel TCTEX1D4 functions. TCTEX1D4 is a dynein light chain that belongs to the DYNT1/TCTEX1 family. In spermatozoa, it appears to be important to sperm motility, intraflagellar transport, and acrosome reaction. To contribute to the knowledge on TCTEX1D4 function in testis and spermatozoa, a yeast two-hybrid assay was performed in testis, which allowed the identification of 40 novel TCTEX1D4 interactors. Curiously, another dynein light chain, TCTEX1D2, was identified and its existence demonstrated for the first time in human spermatozoa. Immunofluorescence studies proved that TCTEX1D2 is an intra-acrosomal protein also present in the midpiece, suggesting a role in cargo movement in human spermatozoa. Further, an in silico profile of TCTEX1D4 revealed that most TCTEX1D4 interacting proteins were not previously characterized and the ones described present a very broad nature. This reinforces TCTEX1D4 as a dynein light chain that is capable of interacting with a variety of functionally different proteins. These observations collectively contribute to a deeper molecular understanding of the human spermatozoa function. PMID:24606217

  8. TCTEX1D4 interactome in human testis: unraveling the function of dynein light chain in spermatozoa.

    PubMed

    Freitas, Maria João; Korrodi-Gregório, Luís; Morais-Santos, Filipa; Cruz e Silva, Edgar da; Fardilha, Margarida

    2014-04-01

    Studies were designed to identify the TCTEX1D4 interactome in human testis, with the purpose of unraveling putative protein complexes essential to male reproduction and thus novel TCTEX1D4 functions. TCTEX1D4 is a dynein light chain that belongs to the DYNT1/TCTEX1 family. In spermatozoa, it appears to be important to sperm motility, intraflagellar transport, and acrosome reaction. To contribute to the knowledge on TCTEX1D4 function in testis and spermatozoa, a yeast two-hybrid assay was performed in testis, which allowed the identification of 40 novel TCTEX1D4 interactors. Curiously, another dynein light chain, TCTEX1D2, was identified and its existence demonstrated for the first time in human spermatozoa. Immunofluorescence studies proved that TCTEX1D2 is an intra-acrosomal protein also present in the midpiece, suggesting a role in cargo movement in human spermatozoa. Further, an in silico profile of TCTEX1D4 revealed that most TCTEX1D4 interacting proteins were not previously characterized and the ones described present a very broad nature. This reinforces TCTEX1D4 as a dynein light chain that is capable of interacting with a variety of functionally different proteins. These observations collectively contribute to a deeper molecular understanding of the human spermatozoa function.

  9. Synthesis, structure and characterization of 4,4‧-bipyridine directed isolated cluster and 1D chain of iron sulfates

    NASA Astrophysics Data System (ADS)

    Xu, Zhiwei; Fu, Yunlong; Zhang, Yu

    2008-03-01

    Two 4,4'-bipyridine directed iron sulfates have been synthesized and characterized by single-crystal X-ray diffraction, infrared spectrum, powder X-ray diffraction, CHN elemental analysis, thermal gravimetric analysis and magnetic analysis. [C 10N 2H 10] 2[Fe 4O 2(SO 4) 6(H 2O) 4]·6H 2O, I, and [C 10N 2H 10][Fe(SO 4) 2(OH)]·H 2O, II, both crystallize in triclinic space group P (No. 2). Crystal data: for I, a = 9.2064(8) Å, b = 11.5548(11) Å, c = 11.8130(11) Å, α = 117.3070(10)°, β = 94.650(2)°, γ = 96.493(2)°, V = 1096.79(17) Å 3, Z = 1; for II, a = 7.0382(9) Å, b = 9.0625(12) Å, c = 11.8903(16) Å, α = 100.145(3)°, β = 98.701(2)°, γ = 91.047(3)°, V = 737.17(17) Å 3, Z = 2. Compound I exhibits a rare discrete sulfated tetra-nuclear iron oxo cluster with a butterfly-type arrangement, and II possesses 1D tancoite-type chains. Magnetic properties analysis of I reveals a transformation from ferromagnetism to antiferromagnetism at about 14 K.

  10. A 1D model for the description of mixing-controlled reacting diesel sprays

    SciTech Connect

    Desantesa, J.M.; Pastor, J.V.; Garcia-Oliver, J.M.; Pastor, J.M.

    2009-01-15

    The paper reports an investigation on the transient evolution of diesel flames in terms of fuel-air mixing, spray penetration and combustion rate. A one-dimensional (1D) spray model, which was previously validated for inert diesel sprays, is extended to reacting conditions. The main assumptions of the model are the mixing-controlled hypothesis and the validity of self-similarity for conservative properties. Validation is achieved by comparing model predictions with both CFD gas jet simulations and experimental diesel spray measurements. The 1D model provides valuable insight into the evolution of the flow within the spray (momentum and mass fluxes, tip penetration, etc.) when shifting from inert to reacting conditions. Results show that the transient diesel flame evolution is mainly governed by two combustion-induced effects, namely the reduction in local density and the increase in flame radial width. (author)

  11. Static sign language recognition using 1D descriptors and neural networks

    NASA Astrophysics Data System (ADS)

    Solís, José F.; Toxqui, Carina; Padilla, Alfonso; Santiago, César

    2012-10-01

    A frame work for static sign language recognition using descriptors which represents 2D images in 1D data and artificial neural networks is presented in this work. The 1D descriptors were computed by two methods, first one consists in a correlation rotational operator.1 and second is based on contour analysis of hand shape. One of the main problems in sign language recognition is segmentation; most of papers report a special color in gloves or background for hand shape analysis. In order to avoid the use of gloves or special clothing, a thermal imaging camera was used to capture images. Static signs were picked up from 1 to 9 digits of American Sign Language, a multilayer perceptron reached 100% recognition with cross-validation.

  12. Lipid and glycolipid antigens of CD1d-restricted natural killer T cells

    PubMed Central

    Venkataswamy, Manjunatha M.; Porcelli, Steven A.

    2009-01-01

    In spite of their relatively limited antigen receptor repertoire, CD1d-restricted NKT cells recognize a surprisingly diverse range of lipid and glycolipid antigens. Recent studies of natural and synthetic CD1d presented antigens provide an increasingly detailed picture of how the specific structural features of these lipids and glycolipids influence their ability to be presented to NKT cells and stimulate their diverse immunologic functions. Particularly for synthetic analogues of α-galactosylceramides which have been the focus of intense recent investigation, it is becoming clear that the design of glycolipid antigens with the ability to precisely control the specific immunologic activities of NKT cells is likely to be feasible. The emerging details of the mechanisms underlying the structure-activity relationship of NKT cell antigens will assist greatly in the design and production of immunomodulatory agents for the precise manipulation of NKT cells and the many other components of the immune system that they influence. PMID:19945296

  13. 1D Scaling with Ablation for K-Shell Radiation from Stainless Steel Wire Arrays

    SciTech Connect

    Giuliani, J. L.; Thornhill, J. W.; Dasgupta, A.; Davis, J.; Clark, R. W.; Jones, B.; Cuneo, M.; Coverdale, C. A.; Deeney, C.

    2009-01-21

    A 1D Lagrangian magnetohydrodynamic z-pinch simulation code is extended to include wire ablation. The plasma transport coefficients are calibrated to reproduce the K-shell yields measured on the Z generator for three stainless steel arrays of diameter 55 mm and masses ranging from 1.8 to 2.7 mg. The resulting 1D scaling model is applied to a larger SS array (65 mm and 2.5 mg) on the refurbished Z machine. Simulation results predict a maximum K-shell yield of 77 kJ for an 82 kV charging voltage. This maximum drops to 42 kJ at 75 kV charging. Neglecting the ablation precursor leads to a {approx}10% change in the calculated yield.

  14. Slice imaging of nitric acid photodissociation: The O({sup 1}D) + HONO channel

    SciTech Connect

    Herath, Nuradhika; Everhart, Stephanie C.; Suits, Arthur G.; Vasyuntinskii, Oleg S.

    2011-01-21

    We report an imaging study of nitric acid (HNO{sub 3}) photodissociation near 204 nm with detection of O({sup 1}D), one of the major decomposition products in this region. The images show structure reflecting the vibrational distribution of the HONO coproduct and significant angular anisotropy that varies with recoil speed. The images also show substantial alignment of the O({sup 1}D) orbital, which is analyzed using an approximate treatment that reveals that the polarization is dominated by incoherent, high order contributions. The results offer additional insight into the dynamics of the dissociation of nitric acid through the S{sub 3} (2 {sup 1}A{sup '}) excited state, resolving an inconsistency in previously reported angular distributions, and pointing the way to future studies of the angular momentum polarization.

  15. Evaluated rate constants for selected HCFC's and HFC's with OH and O((sup)1D)

    NASA Technical Reports Server (NTRS)

    Hampson, Robert F.; Kurylo, Michael J.; Sander, Stanley P.

    1990-01-01

    The chemistry of HCFC's and HFC's in the troposphere is controlled by reactions with OH in which a hydrogen atom is abstracted from the halocarbon to form water and a halo-alkyl radical. The halo-alkyl radical subsequently reacts with molecular oxygen to form a peroxy radical. The reactions of HCFC's and HFC's with O(exp1D) atoms are unimportant in the troposphere, but may be important in producing active chlorine of OH in the stratosphere. Here, the rate constants for the reactions of OH and O(exp1D) with many HFC's and HCFC's are evaluated. Recommendations are given for the five HCFC's and three HFC's specified by AFEAS as primary alternatives as well as for all other isomers of C1 and C2 HCFC's and HFC's where rate data exist. In addition, recommendations are included for CH3CCl3, CH2Cl2, and CH4.

  16. Analytical investigations of the magnetotelluric directionality estimation in 1-D anisotropic layered media

    NASA Astrophysics Data System (ADS)

    Okazaki, T.; Oshiman, N.; Yoshimura, R.

    2016-11-01

    Inferring geoelectric dimensionality (1D, 2D or 3D) and directionality (strike directions) from the impedance tensor is a basic procedure in magnetotelluric data processing. Given that electrical anisotropy is increasingly recognized in observations, it is valuable to understand the imprint of anisotropy in these analyses. In this paper, we analytically investigate the estimation of strike directions based on rotational invariants in 1D anisotropic layered media. We first show that if anisotropy axes are identical in all anisotropic layers, the estimated strike coincides with that direction. We then derive an analytical formula of the strike angle at long periods for general anisotropic layers with an isotropic basement. This formula shows a clear physical interpretation that the strike angle points where the conductance integrated along depth takes a maximum value.

  17. Bifurcations of families of 1D-tori in 4D symplectic maps.

    PubMed

    Onken, Franziska; Lange, Steffen; Ketzmerick, Roland; Bäcker, Arnd

    2016-06-01

    The regular structures of a generic 4d symplectic map with a mixed phase space are organized by one-parameter families of elliptic 1d-tori. Such families show prominent bends, gaps, and new branches. We explain these features in terms of bifurcations of the families when crossing a resonance. For these bifurcations, no external parameter has to be varied. Instead, the longitudinal frequency, which varies along the family, plays the role of the bifurcation parameter. As an example, we study two coupled standard maps by visualizing the elliptic and hyperbolic 1d-tori in a 3d phase-space slice, local 2d projections, and frequency space. The observed bifurcations are consistent with the analytical predictions previously obtained for quasi-periodically forced oscillators. Moreover, the new families emerging from such a bifurcation form the skeleton of the corresponding resonance channel.

  18. Localized self-heating in large arrays of 1D nanostructures

    NASA Astrophysics Data System (ADS)

    Monereo, O.; Illera, S.; Varea, A.; Schmidt, M.; Sauerwald, T.; Schütze, A.; Cirera, A.; Prades, J. D.

    2016-02-01

    One dimensional (1D) nanostructures offer a promising path towards highly efficient heating and temperature control in integrated microsystems. The so called self-heating effect can be used to modulate the response of solid state gas sensor devices. In this work, efficient self-heating was found to occur at random networks of nanostructured systems with similar power requirements to highly ordered systems (e.g. individual nanowires, where their thermal efficiency was attributed to the small dimensions of the objects). Infrared thermography and Raman spectroscopy were used to map the temperature profiles of films based on random arrangements of carbon nanofibers during self-heating. Both the techniques demonstrate consistently that heating concentrates in small regions, the here-called ``hot-spots''. On correlating dynamic temperature mapping with electrical measurements, we also observed that these minute hot-spots rule the resistance values observed macroscopically. A physical model of a random network of 1D resistors helped us to explain this observation. The model shows that, for a given random arrangement of 1D nanowires, current spreading through the network ends up defining a set of spots that dominate both the electrical resistance and power dissipation. Such highly localized heating explains the high power savings observed in larger nanostructured systems. This understanding opens a path to design highly efficient self-heating systems, based on random or pseudo-random distributions of 1D nanostructures.One dimensional (1D) nanostructures offer a promising path towards highly efficient heating and temperature control in integrated microsystems. The so called self-heating effect can be used to modulate the response of solid state gas sensor devices. In this work, efficient self-heating was found to occur at random networks of nanostructured systems with similar power requirements to highly ordered systems (e.g. individual nanowires, where their thermal

  19. Channel specific rate constants for reactions of O(1D) with HCl and HBr

    NASA Technical Reports Server (NTRS)

    Wine, P. H.; Wells, J. R.; Ravishankara, A. R.

    1986-01-01

    The absolute rate coefficients and product yields for reactions of O(1D) with HCl(1) and HBr(2) at 287 K are presently determined by means of the time-resolved resonance fluorescence detection of O(3P) and H(2S) in conjunction with pulsed laser photolysis of O3/HX/He mixtures. Total rate coefficients for O(1D) removal are found to be, in units of 10 to the -10th cu cm/molecule per sec, k(1) = 1.50 + or - 0.18 and k(2) 1.48 + or - 0.16; the absolute accuracy of these rate coefficients is estimated to be + or - 20 percent.

  20. Formation of Water Chains on CaO(001): What Drives the 1D Growth?

    PubMed

    Zhao, Xunhua; Shao, Xiang; Fujimori, Yuichi; Bhattacharya, Saswata; Ghiringhelli, Luca M; Freund, Hans-Joachim; Sterrer, Martin; Nilius, Niklas; Levchenko, Sergey V

    2015-04-01

    Formation of partly dissociated water chains is observed on CaO(001) films upon water exposure at 300 K. While morphology and orientation of the 1D assemblies are revealed from scanning tunneling microscopy, their atomic structure is identified with infrared absorption spectroscopy combined with density functional theory calculations. The latter exploit an ab initio genetic algorithm linked to atomistic thermodynamics to determine low-energy H2O configurations on the oxide surface. The development of 1D structures on the C4v symmetric CaO(001) is triggered by symmetry-broken water tetramers and a favorable balance between adsorbate-adsorbate versus adsorbate-surface interactions at the constraint of the CaO lattice parameter.

  1. Measuring Spin-Charge Separation in a 1D Fermi Gas

    NASA Astrophysics Data System (ADS)

    Fry, Jacob A.; Revelle, Melissa C.; Hulet, Randall G.

    2016-05-01

    We present progress on measurement of spin-charge separation in a two-component, strongly interacting, 1D gas of fermionic lithium. A characteristic feature of interacting 1D Fermi gases is that the velocity of a charge excitation propagates faster than a spin excitation. We create an excitation by applying a dipole force at the center of the cloud using a sheet of light. Depending on the detuning of this beam, we can either excite both spin species equally (charge excitation) or preferentially (spin excitation). Once this beam is turned off, the excitations propagate to the edges of the atomic cloud at a velocity determined by coupling strength. A magnetically tuned Feshbach resonance enables us to vary this coupling and map out the velocities of spin and charge excitations. Supported by an ARO MURI Grant, NSF, and The Welch Foundation

  2. The Dmca1D channel mediates Ca(2+) inward currents in Drosophila embryonic muscles.

    PubMed

    Hara, Yusuke; Koganezawa, Masayuki; Yamamoto, Daisuke

    2015-01-01

    We studied, in a genetic model organism, Drosophila melanogaster, the channel mechanisms underlying membrane excitation in the embryonic body wall muscle whose biophysical properties have been poorly characterized. The inward current underlying the action potential was solely mediated by a high-threshold class of voltage-gated Ca(2+) channels, which exhibited slow inactivation, Ca(2+) permeability with saturation at high [Ca(2+)]OUT, and sensitivity to a Ca(2+) channel blocker, Cd(2+). The Ca(2+) current in the embryonic muscle was completely eliminated in Dmca1D mutants, indicating that the Dmca1D-encoded Ca(2+) channel is the major mediator of inward currents in the body wall muscles throughout the embryonic and larval stages. PMID:26004544

  3. Bifurcations of families of 1D-tori in 4D symplectic maps

    NASA Astrophysics Data System (ADS)

    Onken, Franziska; Lange, Steffen; Ketzmerick, Roland; Bäcker, Arnd

    2016-06-01

    The regular structures of a generic 4d symplectic map with a mixed phase space are organized by one-parameter families of elliptic 1d-tori. Such families show prominent bends, gaps, and new branches. We explain these features in terms of bifurcations of the families when crossing a resonance. For these bifurcations, no external parameter has to be varied. Instead, the longitudinal frequency, which varies along the family, plays the role of the bifurcation parameter. As an example, we study two coupled standard maps by visualizing the elliptic and hyperbolic 1d-tori in a 3d phase-space slice, local 2d projections, and frequency space. The observed bifurcations are consistent with the analytical predictions previously obtained for quasi-periodically forced oscillators. Moreover, the new families emerging from such a bifurcation form the skeleton of the corresponding resonance channel.

  4. Membranes having aligned 1-D nanoparticles in a matrix layer for improved fluid separation

    DOEpatents

    Revanur, Ravindra; Lulevich, Valentin; Roh, Il Juhn; Klare, Jennifer E.; Kim, Sangil; Noy, Aleksandr; Bakajin, Olgica

    2015-12-22

    Membranes for fluid separation are disclosed. These membranes have a matrix layer sandwiched between an active layer and a porous support layer. The matrix layer includes 1-D nanoparticles that are vertically aligned in a porous polymer matrix, and which substantially extend through the matrix layer. The active layer provides species-specific transport, while the support layer provides mechanical support. A matrix layer of this type has favorable surface morphology for forming the active layer. Furthermore, the pores that form in the matrix layer tend to be smaller and more evenly distributed as a result of the presence of aligned 1-D nanoparticles. Improved performance of separation membranes of this type is attributed to these effects.

  5. 1-D seismic velocity model and hypocenter relocation using double difference method around West Papua region

    SciTech Connect

    Sabtaji, Agung E-mail: agung.sabtaji@bmkg.go.id; Nugraha, Andri Dian

    2015-04-24

    West Papua region has fairly high of seismicity activities due to tectonic setting and many inland faults. In addition, the region has a unique and complex tectonic conditions and this situation lead to high potency of seismic hazard in the region. The precise earthquake hypocenter location is very important, which could provide high quality of earthquake parameter information and the subsurface structure in this region to the society. We conducted 1-D P-wave velocity using earthquake data catalog from BMKG for April, 2009 up to March, 2014 around West Papua region. The obtained 1-D seismic velocity then was used as input for improving hypocenter location using double-difference method. The relocated hypocenter location shows fairly clearly the pattern of intraslab earthquake beneath New Guinea Trench (NGT). The relocated hypocenters related to the inland fault are also observed more focus in location around the fault.

  6. A 1D (radial) Plasma Jet Propagation Study for the Plasma Liner Experiment (PLX)

    NASA Astrophysics Data System (ADS)

    Thompson, J. R.; Bogatu, I. N.; Galkin, S. A.; Kim, J. S.; Welch, D. R.; Thoma, C.; Golovkin, I.; Macfarlane, J. J.; Case, A.; Messer, S. J.; Witherspoon, F. D.; Cassibry, J. T.; Awe, T. J.; Hsu, S. C.

    2011-10-01

    The Plasma Liner Experiment will explore the formation of imploding spherical ``plasma liners'' that reach peak pressures of 0.1 Mbar upon stagnation. The liners will be formed through the merging of dense, high velocity plasma jets (n ~1017 cm-3, T ~3 eV, v ~50 km/s) in a spherically convergent geometry. The focus of this 1D (radial) study is argon plasma jet evolution during propagation from the rail gun source to the jet merging radius. The study utilizes the Large Scale Plasma (LSP) PIC code with atomic physics included through the use of a non-Local Thermal Equilibrium (NLTE) Equation of State (EOS) table. We will present scenarios for expected 1D (radial) plasma jet evolution, from upon exiting the PLX rail gun to reaching the jet merging radius. The importance of radiation cooling early in the simulation is highlighted. Work supported by US DOE grant DE-FG02-05ER54835.

  7. Stabilization of Ca1-dFe2-xMnxO4 (0.44 lt x lt 2) with CaFe2O4-type Structure and Ca2plus Defects in 1D Channels

    SciTech Connect

    T Yang; M Croft; A Ignatov; I Nowik; R Cong; M Greenblatt

    2011-12-31

    Solid solutions of Ca{sub 1-{delta}}Fe{sub 2-x}Mn{sub x}O{sub 4} (0.45 {<=} x {<=} 2) were synthesized from CaCl{sub 2} as flux at 850 C in air. The entire series, even with x = 2, crystallizes in the CaFe{sub 2}O{sub 4}-type structure (Pnma), rather than in the CaMn{sub 2}O{sub 4}-type structure (Pbcm). Rietveld refinements confirmed mixed-valency Mn{sup 3+}/Mn{sup 4+} and a substantial level of Ca{sup 2+} deficiency ({delta} {approx} 0.25) at high x. With increasing x, the unit-cell dimensions a and b decrease, while that of c increases. Detailed structural analyses, together with Mn K-edge X-ray absorption and {sup 57}Fe Moessbauer spectroscopy studies, revealed that the stabilization of CaFe{sub 2}O{sub 4}-type structure, even at high values of x, is due to the existence of non-Jahn-Teller active Mn{sup 4+} (and Fe{sup 3+}), which is compensated by the formation of the Ca{sup 2+} deficiencies in the one-dimensional (1D) channels of Ca{sub 1-{delta}}Fe{sub 2-x}Mn{sub x}O{sub 4} during the flux synthesis. Antiferromagnetic (AFM) long-range ordering is achieved for all compounds at low temperature, because of strong AFM interactions between Mn{sup 3+}/Mn{sup 4+} and Fe{sup 3+}. In addition, a spin (or cluster) glass component was also observed, as expected, because of the extensive Mn/Fe structural and Mn{sup 3+}/Mn{sup 4+} charge disordering.

  8. Mosaic PPM1D mutations are associated with predisposition to breast and ovarian cancer.

    PubMed

    Ruark, Elise; Snape, Katie; Humburg, Peter; Loveday, Chey; Bajrami, Ilirjana; Brough, Rachel; Rodrigues, Daniel Nava; Renwick, Anthony; Seal, Sheila; Ramsay, Emma; Duarte, Silvana Del Vecchio; Rivas, Manuel A; Warren-Perry, Margaret; Zachariou, Anna; Campion-Flora, Adriana; Hanks, Sandra; Murray, Anne; Ansari Pour, Naser; Douglas, Jenny; Gregory, Lorna; Rimmer, Andrew; Walker, Neil M; Yang, Tsun-Po; Adlard, Julian W; Barwell, Julian; Berg, Jonathan; Brady, Angela F; Brewer, Carole; Brice, Glen; Chapman, Cyril; Cook, Jackie; Davidson, Rosemarie; Donaldson, Alan; Douglas, Fiona; Eccles, Diana; Evans, D Gareth; Greenhalgh, Lynn; Henderson, Alex; Izatt, Louise; Kumar, Ajith; Lalloo, Fiona; Miedzybrodzka, Zosia; Morrison, Patrick J; Paterson, Joan; Porteous, Mary; Rogers, Mark T; Shanley, Susan; Walker, Lisa; Gore, Martin; Houlston, Richard; Brown, Matthew A; Caufield, Mark J; Deloukas, Panagiotis; McCarthy, Mark I; Todd, John A; Turnbull, Clare; Reis-Filho, Jorge S; Ashworth, Alan; Antoniou, Antonis C; Lord, Christopher J; Donnelly, Peter; Rahman, Nazneen

    2013-01-17

    Improved sequencing technologies offer unprecedented opportunities for investigating the role of rare genetic variation in common disease. However, there are considerable challenges with respect to study design, data analysis and replication. Using pooled next-generation sequencing of 507 genes implicated in the repair of DNA in 1,150 samples, an analytical strategy focused on protein-truncating variants (PTVs) and a large-scale sequencing case-control replication experiment in 13,642 individuals, here we show that rare PTVs in the p53-inducible protein phosphatase PPM1D are associated with predisposition to breast cancer and ovarian cancer. PPM1D PTV mutations were present in 25 out of 7,781 cases versus 1 out of 5,861 controls (P = 1.12 × 10(-5)), including 18 mutations in 6,912 individuals with breast cancer (P = 2.42 × 10(-4)) and 12 mutations in 1,121 individuals with ovarian cancer (P = 3.10 × 10(-9)). Notably, all of the identified PPM1D PTVs were mosaic in lymphocyte DNA and clustered within a 370-base-pair region in the final exon of the gene, carboxy-terminal to the phosphatase catalytic domain. Functional studies demonstrate that the mutations result in enhanced suppression of p53 in response to ionizing radiation exposure, suggesting that the mutant alleles encode hyperactive PPM1D isoforms. Thus, although the mutations cause premature protein truncation, they do not result in the simple loss-of-function effect typically associated with this class of variant, but instead probably have a gain-of-function effect. Our results have implications for the detection and management of breast and ovarian cancer risk. More generally, these data provide new insights into the role of rare and of mosaic genetic variants in common conditions, and the use of sequencing in their identification. PMID:23242139

  9. INFIL1D: a quasi-analytical model for simulating one-dimensional, constant flux infiltration

    SciTech Connect

    Simmons, C.S.; McKeon, T.J.

    1984-04-01

    The program INFIL1D is designed to calculate approximate wetting-front advance into an unsaturated, uniformly moist, homogeneous soil profile, under constant surface-flux conditions. The code is based on a quasi-analytical method, which utilizes an assumed invariant functional relationship between reduced (normalized) flux and water content. The code uses general hydraulic property data in tabular form to simulate constant surface-flux infiltration. 10 references, 4 figures.

  10. Mosaic PPM1D mutations are associated with predisposition to breast and ovarian cancer.

    PubMed

    Ruark, Elise; Snape, Katie; Humburg, Peter; Loveday, Chey; Bajrami, Ilirjana; Brough, Rachel; Rodrigues, Daniel Nava; Renwick, Anthony; Seal, Sheila; Ramsay, Emma; Duarte, Silvana Del Vecchio; Rivas, Manuel A; Warren-Perry, Margaret; Zachariou, Anna; Campion-Flora, Adriana; Hanks, Sandra; Murray, Anne; Ansari Pour, Naser; Douglas, Jenny; Gregory, Lorna; Rimmer, Andrew; Walker, Neil M; Yang, Tsun-Po; Adlard, Julian W; Barwell, Julian; Berg, Jonathan; Brady, Angela F; Brewer, Carole; Brice, Glen; Chapman, Cyril; Cook, Jackie; Davidson, Rosemarie; Donaldson, Alan; Douglas, Fiona; Eccles, Diana; Evans, D Gareth; Greenhalgh, Lynn; Henderson, Alex; Izatt, Louise; Kumar, Ajith; Lalloo, Fiona; Miedzybrodzka, Zosia; Morrison, Patrick J; Paterson, Joan; Porteous, Mary; Rogers, Mark T; Shanley, Susan; Walker, Lisa; Gore, Martin; Houlston, Richard; Brown, Matthew A; Caufield, Mark J; Deloukas, Panagiotis; McCarthy, Mark I; Todd, John A; Turnbull, Clare; Reis-Filho, Jorge S; Ashworth, Alan; Antoniou, Antonis C; Lord, Christopher J; Donnelly, Peter; Rahman, Nazneen

    2013-01-17

    Improved sequencing technologies offer unprecedented opportunities for investigating the role of rare genetic variation in common disease. However, there are considerable challenges with respect to study design, data analysis and replication. Using pooled next-generation sequencing of 507 genes implicated in the repair of DNA in 1,150 samples, an analytical strategy focused on protein-truncating variants (PTVs) and a large-scale sequencing case-control replication experiment in 13,642 individuals, here we show that rare PTVs in the p53-inducible protein phosphatase PPM1D are associated with predisposition to breast cancer and ovarian cancer. PPM1D PTV mutations were present in 25 out of 7,781 cases versus 1 out of 5,861 controls (P = 1.12 × 10(-5)), including 18 mutations in 6,912 individuals with breast cancer (P = 2.42 × 10(-4)) and 12 mutations in 1,121 individuals with ovarian cancer (P = 3.10 × 10(-9)). Notably, all of the identified PPM1D PTVs were mosaic in lymphocyte DNA and clustered within a 370-base-pair region in the final exon of the gene, carboxy-terminal to the phosphatase catalytic domain. Functional studies demonstrate that the mutations result in enhanced suppression of p53 in response to ionizing radiation exposure, suggesting that the mutant alleles encode hyperactive PPM1D isoforms. Thus, although the mutations cause premature protein truncation, they do not result in the simple loss-of-function effect typically associated with this class of variant, but instead probably have a gain-of-function effect. Our results have implications for the detection and management of breast and ovarian cancer risk. More generally, these data provide new insights into the role of rare and of mosaic genetic variants in common conditions, and the use of sequencing in their identification.

  11. Development of a hybrid deterministic/stochastic method for 1D nuclear reactor kinetics

    SciTech Connect

    Terlizzi, Stefano; Dulla, Sandra; Ravetto, Piero; Rahnema, Farzad; Zhang, Dingkang

    2015-12-31

    A new method has been implemented for solving the time-dependent neutron transport equation efficiently and accurately. This is accomplished by coupling the hybrid stochastic-deterministic steady-state coarse-mesh radiation transport (COMET) method [1,2] with the new predictor-corrector quasi-static method (PCQM) developed at Politecnico di Torino [3]. In this paper, the coupled method is implemented and tested in 1D slab geometry.

  12. Transfer Matrix Approach to 1d Random Band Matrices: Density of States

    NASA Astrophysics Data System (ADS)

    Shcherbina, Mariya; Shcherbina, Tatyana

    2016-08-01

    We study the special case of n× n 1D Gaussian Hermitian random band matrices, when the covariance of the elements is determined by the matrix J=(-W^2triangle +1)^{-1} . Assuming that n≥ CW log W≫ 1 , we prove that the averaged density of states coincides with the Wigner semicircle law up to the correction of order W^{-1}.

  13. Mosaic PPM1D mutations are associated with predisposition to breast and ovarian cancer

    PubMed Central

    Ruark, Elise; Snape, Katie; Humburg, Peter; Loveday, Chey; Bajrami, Ilirjana; Brough, Rachel; Rodrigues, Daniel Nava; Renwick, Anthony; Seal, Sheila; Ramsay, Emma; Duarte, Silvana Del Vecchio; Rivas, Manuel A.; Warren-Perry, Margaret; Zachariou, Anna; Campion-Flora, Adriana; Hanks, Sandra; Murray, Anne; Pour, Naser Ansari; Douglas, Jenny; Gregory, Lorna; Rimmer, Andrew; Walker, Neil M.; Yang, Tsun-Po; Adlard, Julian W.; Barwell, Julian; Berg, Jonathan; Brady, Angela F.; Brewer, Carole; Brice, Glen; Chapman, Cyril; Cook, Jackie; Davidson, Rosemarie; Donaldson, Alan; Douglas, Fiona; Eccles, Diana; Evans, D. Gareth; Greenhalgh, Lynn; Henderson, Alex; Izatt, Louise; Kumar, Ajith; Lalloo, Fiona; Miedzybrodzka, Zosia; Morrison, Patrick J.; Paterson, Joan; Porteous, Mary; Rogers, Mark T.; Shanley, Susan; Walker, Lisa; Gore, Martin; Houlston, Richard; Brown, Matthew A.; Caufield, Mark J.; Deloukas, Panagiotis; McCarthy, Mark I.; Todd, John A.; Turnbull, Clare; Reis-Filho, Jorge S.; Ashworth, Alan; Antoniou, Antonis C.; Lord, Christopher J.; Donnelly, Peter; Rahman, Nazneen

    2013-01-01

    Improved sequencing technologies offer unprecedented opportunities for investigating the role of rare genetic variation in common disease. However, there are considerable challenges with respect to study design, data analysis and replication1. Here, using pooled next-generation sequencing of 507 genes implicated in the repair of DNA in 1,150 samples, an analytical strategy focussed on protein truncating variants (PTVs) and a large-scale sequencing case-control replication experiment in 13,642 individuals, we show that rare PTVs in the p53 inducible protein phosphatase PPM1D are associated with predisposition to breast cancer and to ovarian cancer. PPM1D PTV mutations were present in 25/7781 cases vs 1/5861 controls; P=1.12×10−5, which included 18 mutations in 6,912 individuals with breast cancer; P = 2.42×10−4 and 12 mutations in 1,121 individuals with ovarian cancer; P = 3.10×10−9. Notably, all the identified PPM1D PTVs were mosaic in lymphocyte DNA and clustered within a 370 bp region in the final exon of the gene, C-terminal to the phosphatase catalytic domain. Functional studies demonstrated that the mutations result in enhanced suppression of p53 in response to ionising radiation exposure, suggesting the mutant alleles encode hyperactive PPM1D isoforms. Thus, although the mutations cause premature protein truncation, they do not result in the simple loss-of-function typically associated with this class of variant, but instead likely have a gain-of-function effect. Our results have implications for the detection and management of breast and ovarian cancer risk. More generally, these data provide new insights into the role of rare and of mosaic genetic variants in common conditions, and the utility of sequencing in their identification. PMID:23242139

  14. Discontinuous Galerkin finite element method applied to the 1-D spherical neutron transport equation

    SciTech Connect

    Machorro, Eric . E-mail: machorro@amath.washington.edu

    2007-04-10

    Discontinuous Galerkin finite element methods are used to estimate solutions to the non-scattering 1-D spherical neutron transport equation. Various trial and test spaces are compared in the context of a few sample problems whose exact solution is known. Certain trial spaces avoid unphysical behaviors that seem to plague other methods. Comparisons with diamond differencing and simple corner-balancing are presented to highlight these improvements.

  15. Subscale study of engine bellmouth inlet vortices in test cell R1D

    NASA Astrophysics Data System (ADS)

    Reed, James A.; Hiers, Robert S., Jr.

    1995-05-01

    A technology program was conducted in Test Cell R1D concerning bellmouth flow quality. Flow visualization was used to determine the presence of inlet vortices. It was shown that these vortices can be eliminated using a 45-deg conical extension attached to the bellmouth inlet. Design guidelines were developed to assist in determining acceptable cone angles and axial and radial gaps between the conical extension and the bellmouth inlet.

  16. Scattering coefficients and gray-body factor for 1D BEC acoustic black holes: Exact results

    NASA Astrophysics Data System (ADS)

    Fabbri, Alessandro; Balbinot, Roberto; Anderson, Paul R.

    2016-03-01

    A complete set of exact analytic solutions to the mode equation is found in the region exterior to the acoustic horizon for a class of 1D Bose-Einstein condensate acoustic black holes. From these, analytic expressions for the scattering coefficients and gray-body factor are obtained. The results are used to verify previous predictions regarding the behaviors of the scattering coefficients and gray-body factor in the low-frequency limit.

  17. Regulation of anthocyanin biosynthesis in Arabidopsis thaliana red pap1-D cells metabolically programmed by auxins.

    PubMed

    Liu, Zhong; Shi, Ming-Zhu; Xie, De-Yu

    2014-04-01

    Red pap1-D cells of Arabidopsis thaliana have been cloned from production of anthocyanin pigmentation 1-Dominant (pap1-D) plants. The red cells are metabolically programmed to produce high levels of anthocyanins by a WD40-bHLH-MYB complex that is composed of the TTG1, TT8/GL3 and PAP1 transcription factors. Here, we report that indole 3-acetic acid (IAA), naphthaleneacetic acid (NAA) and 2,4-dichlorophenoxyacetic acid (2,4-D) regulate anthocyanin biosynthesis in these red cells. Seven concentrations (0, 0.2, 0.4, 2.2, 9, 18 and 27 μM) were tested for the three auxins. IAA and 2,4-D at 2.2-27 μM reduced anthocyanin levels. NAA at 0-0.2 μM or above 9 μM also decreased anthocyanin levels, but from 0.4 to 9 μM, it increased them. HPLC-ESI-MS analysis identified seven cyanin molecules that were produced in red pap1-D cells, and their levels were affected by auxins. The expression levels of ten genes, including six transcription factors (TTG1, EGL3, MYBL2, TT8, GL3 and PAP1) and four pathway genes (PAL1, CHS, DFR and ANS) involved in anthocyanin biosynthesis were analyzed upon various auxin treatments. The resulting data showed that 2,4-D, NAA and IAA control anthocyanin biosynthesis by regulating the expression of TT8, GL3 and PAP1 as well as genes in the anthocyanin biosynthetic pathway, such as DFR and ANS. In addition, the expression of MYBL2, PAL1 and CHS in red pap1-D and wild-type cells differentially respond to the three auxins. Our data demonstrate that the three auxins regulate anthocyanin biosynthesis in metabolically programmed red cells via altering the expression of transcription factor genes and pathway genes. PMID:24370633

  18. Development of a hybrid deterministic/stochastic method for 1D nuclear reactor kinetics

    NASA Astrophysics Data System (ADS)

    Terlizzi, Stefano; Rahnema, Farzad; Zhang, Dingkang; Dulla, Sandra; Ravetto, Piero

    2015-12-01

    A new method has been implemented for solving the time-dependent neutron transport equation efficiently and accurately. This is accomplished by coupling the hybrid stochastic-deterministic steady-state coarse-mesh radiation transport (COMET) method [1,2] with the new predictor-corrector quasi-static method (PCQM) developed at Politecnico di Torino [3]. In this paper, the coupled method is implemented and tested in 1D slab geometry.

  19. A 1D exact treatment of shock waves within spectral methods in plane geometry

    NASA Astrophysics Data System (ADS)

    Bonazzola, Silvano; Marck, Jean-Alain

    1991-12-01

    A high-accuracy numerical technique is presented which employs two moving grids, respectively before and after the shock formation, to solve 1D Euler equations that are coupled with the transport equations for the entropy and the chemical abundances in cases with and without shock formation. Chebychev polynomial series are used to expand quantities on both sides of the matching point, and Rankine-Hugoniot conditions are used to ascertain the shock velocity after shock formation. Illustrative results are presented.

  20. Uranium(VI) coordination polymers with pyromellitate ligand: Unique 1D channel structures and diverse fluorescence

    SciTech Connect

    Zhang, Yingjie; Bhadbhade, Mohan; Karatchevtseva, Inna; Price, Jason R.; Liu, Hao; Zhang, Zhaoming; Kong, Linggen; Čejka, Jiří; Lu, Kim; Lumpkin, Gregory R.

    2015-03-15

    Three new coordination polymers of uranium(VI) with pyromellitic acid (H{sub 4}btca) have been synthesized and structurally characterized. (ED)[(UO{sub 2})(btca)]·(DMSO)·3H{sub 2}O (1) (ED=ethylenediammonium; DMSO=dimethylsulfoxide) has a lamellar structure with intercalation of ED and DMSO. (NH{sub 4}){sub 2}[(UO{sub 2}){sub 6}O{sub 2}(OH){sub 6}(btca)]·~6H{sub 2}O (2) has a 3D framework built from 7-fold coordinated uranyl trinuclear units and btca ligands with 1D diamond-shaped channels (~8.5 Å×~8.6 Å). [(UO{sub 2}){sub 2}(H{sub 2}O)(btca)]·4H{sub 2}O (3) has a 3D network constructed by two types of 7-fold coordinated uranium polyhedron. The unique μ{sub 5}-coordination mode of btca in 3 enables the formation of 1D olive-shaped large channels (~4.5 Å×~19 Å). Vibrational modes, thermal stabilities and fluorescence properties have been investigated. - Graphical abstract: Table of content: three new uranium(VI) coordination polymers with pyromellitic acid (H{sub 4}btca) have been synthesized via room temperature and hydrothermal synthesis methods, and structurally characterized. Two to three dimensional (3D) frameworks are revealed. All 3D frameworks have unique 1D large channels. Their vibrational modes, thermal stabilities and photoluminescence properties have been investigated. - Highlights: • Three new coordination polymers of U(VI) with pyromellitic acid (H{sub 4}btca). • Structures from a 2D layer to 3D frameworks with unique 1D channels. • Unusual µ{sub 5}-(η{sub 1}:η{sub 2}:η{sub 1}:η{sub 2:}η{sub 1}) coordination mode of btca ligand. • Vibrational modes, thermal stabilities and luminescent properties reported.

  1. EXTENSION OF THE 1D FOUR-GROUP ANALYTIC NODAL METHOD TO FULL MULTIGROUP

    SciTech Connect

    B. D. Ganapol; D. W. Nigg

    2008-09-01

    In the mid 80’s, a four-group/two-region, entirely analytical 1D nodal benchmark appeared. It was readily acknowledged that this special case was as far as one could go in terms of group number and still achieve an analytical solution. In this work, we show that by decomposing the solution to the multigroup diffusion equation into homogeneous and particular solutions, extension to any number of groups is a relatively straightforward exercise using the mathematics of linear algebra.

  2. Zero finite-temperature charge stiffness within the half-filled 1D Hubbard model

    SciTech Connect

    Carmelo, J.M.P.; Gu, Shi-Jian; Sacramento, P.D.

    2013-12-15

    Even though the one-dimensional (1D) Hubbard model is solvable by the Bethe ansatz, at half-filling its finite-temperature T>0 transport properties remain poorly understood. In this paper we combine that solution with symmetry to show that within that prominent T=0 1D insulator the charge stiffness D(T) vanishes for T>0 and finite values of the on-site repulsion U in the thermodynamic limit. This result is exact and clarifies a long-standing open problem. It rules out that at half-filling the model is an ideal conductor in the thermodynamic limit. Whether at finite T and U>0 it is an ideal insulator or a normal resistor remains an open question. That at half-filling the charge stiffness is finite at U=0 and vanishes for U>0 is found to result from a general transition from a conductor to an insulator or resistor occurring at U=U{sub c}=0 for all finite temperatures T>0. (At T=0 such a transition is the quantum metal to Mott–Hubbard-insulator transition.) The interplay of the η-spin SU(2) symmetry with the hidden U(1) symmetry beyond SO(4) is found to play a central role in the unusual finite-temperature charge transport properties of the 1D half-filled Hubbard model. -- Highlights: •The charge stiffness of the half-filled 1D Hubbard model is evaluated. •Its value is controlled by the model symmetry operator algebras. •We find that there is no charge ballistic transport at finite temperatures T>0. •The hidden U(1) symmetry controls the U=0 phase transition for T>0.

  3. Piezo-semiconductive quasi-1D nanodevices with or without anti-symmetry.

    PubMed

    Araneo, Rodolfo; Lovat, Giampiero; Burghignoli, Paolo; Falconi, Christian

    2012-09-01

    The piezopotential in floating, homogeneous, quasi-1D piezo-semiconductive nanostructures under axial stress is an anti-symmetric (i.e., odd) function of force. Here, after introducing piezo-nano-devices with floating electrodes for maximum piezo-potential, we show that breaking the anti-symmetric nature of the piezopotential-force relation, for instance by using conical nanowires, can lead to better nanogenerators, piezotronic and piezophototronic devices.

  4. Transfer Matrix Approach to 1d Random Band Matrices: Density of States

    NASA Astrophysics Data System (ADS)

    Shcherbina, Mariya; Shcherbina, Tatyana

    2016-09-01

    We study the special case of n× n 1D Gaussian Hermitian random band matrices, when the covariance of the elements is determined by the matrix J=(-W^2triangle +1)^{-1}. Assuming that n≥ CW log W≫ 1, we prove that the averaged density of states coincides with the Wigner semicircle law up to the correction of order W^{-1}.

  5. Construction and Functions of Cyclodextrin-Based 1D Supramolecular Strands and their Secondary Assemblies.

    PubMed

    Chen, Yong; Liu, Yu

    2015-09-23

    Cyclodextrins (CDs), a class of cyclic oligosaccharides, are water-soluble, nontoxic, and commercial available with a low price, and their well-defined hydrophobic cavity can bind various organic/biological substrates. Through their molecular assembly mediated by organic, inorganic, or polymeric molecules as templates, CDs and their functional derivatives can be assembled to 1D supramolecular strands, wherein the functional groups of the CDs are closely located in a highly ordered manner. This structural feature greatly favors the cooperative effect of numerous functional groups in the supramolecular strand, as well as the interactions of the supramolecular strands with the multiple binding sites of substrates, especially biological substrates. Therefore, CD-based 1D supramolecular strands exhibit many material, biological, and catalytic functions, and these properties can be further improved through their secondary assembly. An overview of recent advances in the development of the construction and functions of CD-based 1D supramolecular strands and their secondary assemblies is given here. It is expected that the representative contributions described can inspire future investigations and lead to discoveries that promote the research of CD-based functional materials. PMID:26270410

  6. Numerical Modeling of Imploding Plasma liners Using the 1D Radiation-Hydrodynamics Code HELIOS

    NASA Astrophysics Data System (ADS)

    Davis, J. S.; Hanna, D. S.; Awe, T. J.; Hsu, S. C.; Stanic, M.; Cassibry, J. T.; Macfarlane, J. J.

    2010-11-01

    The Plasma Liner Experiment (PLX) is attempting to form imploding plasma liners to reach 0.1 Mbar upon stagnation, via 30--60 spherically convergent plasma jets. PLX is partly motivated by the desire to develop a standoff driver for magneto-inertial fusion. The liner density, atomic makeup, and implosion velocity will help determine the maximum pressure that can be achieved. This work focuses on exploring the effects of atomic physics and radiation on the 1D liner implosion and stagnation dynamics. For this reason, we are using Prism Computational Science's 1D Lagrangian rad-hydro code HELIOS, which has both equation of state (EOS) table-lookup and detailed configuration accounting (DCA) atomic physics modeling. By comparing a series of PLX-relevant cases proceeding from ideal gas, to EOS tables, to DCA treatments, we aim to identify how and when atomic physics effects are important for determining the peak achievable stagnation pressures. In addition, we present verification test results as well as brief comparisons to results obtained with RAVEN (1D radiation-MHD) and SPHC (smoothed particle hydrodynamics).

  7. Resonance Raman Spectroscopy of Extreme Nanowires and Other 1D Systems.

    PubMed

    Smith, David C; Spencer, Joseph H; Sloan, Jeremy; McDonnell, Liam P; Trewhitt, Harrison; Kashtiban, Reza J; Faulques, Eric

    2016-01-01

    This paper briefly describes how nanowires with diameters corresponding to 1 to 5 atoms can be produced by melting a range of inorganic solids in the presence of carbon nanotubes. These nanowires are extreme in the sense that they are the limit of miniaturization of nanowires and their behavior is not always a simple extrapolation of the behavior of larger nanowires as their diameter decreases. The paper then describes the methods required to obtain Raman spectra from extreme nanowires and the fact that due to the van Hove singularities that 1D systems exhibit in their optical density of states, that determining the correct choice of photon excitation energy is critical. It describes the techniques required to determine the photon energy dependence of the resonances observed in Raman spectroscopy of 1D systems and in particular how to obtain measurements of Raman cross-sections with better than 8% noise and measure the variation in the resonance as a function of sample temperature. The paper describes the importance of ensuring that the Raman scattering is linearly proportional to the intensity of the laser excitation intensity. It also describes how to use the polarization dependence of the Raman scattering to separate Raman scattering of the encapsulated 1D systems from those of other extraneous components in any sample. PMID:27168195

  8. Dynamics of the reactions of O(1D) with HCl, DCl, and Cl2

    NASA Astrophysics Data System (ADS)

    Matsumi, Yutaka; Tonokura, Kenichi; Kawasaki, Masahiro; Tsuji, Kazuhide; Obi, Kinichi

    1993-05-01

    The reactions O(1D)+HCl→OH+Cl (1a) and OCl+H (1b), O(1D)+DCl→OD+Cl (2a) and OCl+D (2b), and O(1D)+Cl2→OCl+Cl (3) are studied at an average collision energy of 7.6, 7.7, and 8.8 kcal/mol for (1), (2), and (3), respectively. H, D, and Cl atoms are detected by the resonance-enhanced multiphoton ionization technique. The average kinetic energies released to the products are estimated from Doppler profile measurements of the product atoms. The relative yields [OCl+H]/[OH+Cl] and [OCl+D]/[OD+Cl] are directly measured, and a strong isotope effect (H/D) on the relative yields is found. The fine-structure branding ratios [Cl(2P1/2]/[Cl(2P3/2)] of the reaction products are also measured. The results suggest that nonadiabatic couplings take place at the exit channels of the reactions (1a) and (2a), while the reaction (3) is totally adiabatic.

  9. Resonance Raman Spectroscopy of Extreme Nanowires and Other 1D Systems

    PubMed Central

    Smith, David C.; Spencer, Joseph H.; Sloan, Jeremy; McDonnell, Liam P.; Trewhitt, Harrison; Kashtiban, Reza J.; Faulques, Eric

    2016-01-01

    This paper briefly describes how nanowires with diameters corresponding to 1 to 5 atoms can be produced by melting a range of inorganic solids in the presence of carbon nanotubes. These nanowires are extreme in the sense that they are the limit of miniaturization of nanowires and their behavior is not always a simple extrapolation of the behavior of larger nanowires as their diameter decreases. The paper then describes the methods required to obtain Raman spectra from extreme nanowires and the fact that due to the van Hove singularities that 1D systems exhibit in their optical density of states, that determining the correct choice of photon excitation energy is critical. It describes the techniques required to determine the photon energy dependence of the resonances observed in Raman spectroscopy of 1D systems and in particular how to obtain measurements of Raman cross-sections with better than 8% noise and measure the variation in the resonance as a function of sample temperature. The paper describes the importance of ensuring that the Raman scattering is linearly proportional to the intensity of the laser excitation intensity. It also describes how to use the polarization dependence of the Raman scattering to separate Raman scattering of the encapsulated 1D systems from those of other extraneous components in any sample. PMID:27168195

  10. Secure information embedding into 1D biomedical signals based on SPIHT.

    PubMed

    Rubio, Oscar J; Alesanco, Alvaro; García, José

    2013-08-01

    This paper proposes an encoding system for 1D biomedical signals that allows embedding metadata and provides security and privacy. The design is based on the analysis of requirements for secure and efficient storage, transmission and access to medical tests in e-health environment. This approach uses the 1D SPIHT algorithm to compress 1D biomedical signals with clinical quality, metadata embedding in the compressed domain to avoid extra distortion, digital signature to implement security and attribute-level encryption to support Role-Based Access Control. The implementation has been extensively tested using standard electrocardiogram and electroencephalogram databases (MIT-BIH Arrhythmia, MIT-BIH Compression and SCCN-EEG), demonstrating high embedding capacity (e.g. 3 KB in resting ECGs, 200 KB in stress tests, 30 MB in ambulatory ECGs), short delays (2-3.3s in real-time transmission) and compression of the signal (by ≃3 in real-time transmission, by ≃5 in offline operation) despite of the embedding of security elements and metadata to enable e-health services.

  11. E-beam to complement optical lithography for 1D layouts

    NASA Astrophysics Data System (ADS)

    Lam, David K.; Liu, Enden D.; Smayling, Michael C.; Prescop, Ted

    2011-04-01

    The semiconductor industry is moving to highly regular designs, or 1D gridded layouts, to enable scaling to advanced nodes, as well as improve process latitude, chip size and chip energy consumption. The fabrication of highly regular ICs is straightforward. Poly and metal layers are arranged into 1D layouts. These 1D layouts facilitate a two-step patterning approach: a line-creation step, followed by a line-cutting step, to form the desired IC pattern (See Figure 1). The first step, line creation, can be accomplished with a variety of lithography techniques including 193nm immersion (193i) and Self-Aligned Double Patterning (SADP). It appears feasible to create unidirectional parallel lines to at least 11 nm half-pitch, with two applications of SADP for pitch division by four. Potentially, this step can also be accomplished with interference lithography or directed self assembly in the future. The second step, line cutting, requires an extremely high-resolution lithography technique. At advanced nodes, the only options appear to be the costly quadruple patterning with 193i, or EUV or E-Beam Lithography (EBL). This paper focuses on the requirements for a lithography system for "line cutting", using EBL to complement Optical. EBL is the most cost-effective option for line cutting at advanced nodes for HVM.

  12. NMR 1D-imaging of water infiltration into mesoporous matrices.

    PubMed

    Le Feunteun, Steven; Diat, Olivier; Guillermo, Armel; Poulesquen, Arnaud; Podor, Renaud

    2011-04-01

    It is shown that coupling nuclear magnetic resonance (NMR) 1D-imaging with the measure of NMR relaxation times and self-diffusion coefficients can be a very powerful approach to investigate fluid infiltration into porous media. Such an experimental design was used to study the very slow seeping of pure water into hydrophobic materials. We consider here three model samples of nuclear waste conditioning matrices which consist in a dispersion of NaNO(3) (highly soluble) and/or BaSO(4) (poorly soluble) salt grains embedded in a bitumen matrix. Beyond studying the moisture progression according to the sample depth, we analyze the water NMR relaxation times and self-diffusion coefficients along its 1D-concentration profile to obtain spatially resolved information on the solution properties and on the porous structure at different scales. It is also shown that, when the relaxation or self-diffusion properties are multimodal, the 1D-profile of each water population is recovered. Three main levels of information were disclosed along the depth-profiles. They concern (i) the water uptake kinetics, (ii) the salinity and the molecular dynamics of the infiltrated solutions and (iii) the microstructure of the water-filled porosities: open networks coexisting with closed pores. All these findings were fully validated and enriched by NMR cryoporometry experiments and by performing environmental scanning electronic microscopy observations. Surprisingly, results clearly show that insoluble salts enhance the water progression and thereby increase the capability of the material to uptake water.

  13. Neutronic analysis of the 1D and 1E banks reflux detection system

    SciTech Connect

    Blanchard, A.

    1999-12-21

    Two H Canyon neutron monitoring systems for early detection of postulated abnormal reflux conditions in the Second Uranium Cycle 1E and 1D Mixer-Settle Banks have been designed and built. Monte Carlo neutron transport simulations using the general purpose, general geometry, n-particle MCNP code have been performed to model expected response of the monitoring systems to varying conditions.The confirmatory studies documented herein conclude that the 1E and 1D neutron monitoring systems are able to achieve adequate neutron count rates for various neutron source and detector configurations, thereby eliminating excessive integration count time. Neutron count rate sensitivity studies are also performed. Conversely, the transport studies concluded that the neutron count rates are statistically insensitive to nitric acid content in the aqueous region and to the transition region length. These studies conclude that the 1E and 1D neutron monitoring systems are able to predict the postulated reflux conditions for all examined perturbations in the neutron source and detector configurations. In the cases examined, the relative change in the neutron count rates due to postulated transitions from normal {sup 235}U concentration levels to reflux levels remain satisfactory detectable.

  14. Measuring the Speed of Sound in a 1D Fermi Gas

    NASA Astrophysics Data System (ADS)

    Fry, Jacob; Revelle, Melissa; Hulet, Randall

    2016-05-01

    We report measurements of the speed of sound in a two-spin component, 1D gas of fermionic lithium. The 1D system is an array of one-dimensional tubes created by a 2D optical lattice. By increasing the lattice depth, the tunneling between tubes is sufficiently small to make each an independent 1D system. To measure the speed of sound, we create a density notch at the center of the atom cloud using a sheet of light tuned far from resonance. The dipole force felt by both spin states will be equivalent, so this notch can be thought of as a charge excitation. Once this beam is turned off, the notch propagates to the edge of the atomic cloud with a velocity that depends on the strength of interatomic interactions. We control interactions using a magnetically tuned Feshbach resonance, allowing us to measure the speed of sound over a wide range of interaction. This method may be used to extract the Luttinger parameter vs. interaction strength. Supported by an ARO MURI Grant, NSF, and The Welch Foundation.

  15. Mechanisms of action of the 5-HT1B/1D receptor agonists.

    PubMed

    Tepper, Stewart J; Rapoport, Alan M; Sheftell, Fred D

    2002-07-01

    Recent studies of the pathophysiology of migraine provide evidence that the headache phase is associated with multiple physiologic actions. These actions include the release of vasoactive neuropeptides by the trigeminovascular system, vasodilation of intracranial extracerebral vessels, and increased nociceptive neurotransmission within the central trigeminocervical complex. The 5-HT(1B/1D) receptor agonists, collectively known as triptans, are a major advance in the treatment of migraine. The beneficial effects of the triptans in patients with migraine are related to their multiple mechanisms of action at sites implicated in the pathophysiology of migraine. These mechanisms are mediated by 5-HT(1B/1D) receptors and include vasoconstriction of painfully dilated cerebral blood vessels, inhibition of the release of vasoactive neuropeptides by trigeminal nerves, and inhibition of nociceptive neurotransmission. The high affinity of the triptans for 5-HT(1B/1D) receptors and their favorable pharmacologic properties contribute to the beneficial effects of these drugs, including rapid onset of action, effective relief of headache and associated symptoms, and low incidence of adverse effects. PMID:12117355

  16. Reversible interconversion of a divalent vanadium bronze between δ and β quasi-1D structures.

    PubMed

    Marley, Peter M; Banerjee, Sarbajit

    2012-05-01

    Charge fluctuations along the quasi-1D frameworks of M(x)V(2)O(5) bronzes have evinced much recent interest owing to the manifestation of colossal metal-insulator transitions and superconductivity. Depending upon the nature of the intercalating cation (M), distinctive geometries of the V(2)O(5) framework are accessible. Herein, we demonstrate an unprecedented reversible transformation between double-layered (δ) and tunnel (β) quasi-1D geometries for nanowires of a divalent vanadium bronze, Ca(x)V(2)O(5) (x ≈ 0.23), upon annealing-induced dehydration and hydrothermally induced hydration. Such a facile hydration/dehydration-induced interconversion between two prominent quasi-1D structures (accompanied by a change in charge-ordering motifs) has not been observed in the bulk and is posited to result from the ease of propagation of crystallographic slip processes across the confined nanowire widths for the δ → β conversion and the facile diffusion of water molecules within the tunnel geometries for the β → δ reversion.

  17. Toward a consistent use of overshooting parametrizations in 1D stellar evolution codes

    NASA Astrophysics Data System (ADS)

    Viallet, M.; Meakin, C.; Prat, V.; Arnett, D.

    2015-08-01

    Several parametrizations for overshooting in 1D stellar evolution calculations coexist in the literature. These parametrizations are used somewhat arbitrarily in stellar evolution codes, based on what works best for a given problem or even for the historical reasons related to the development of each code. We point out that these different parametrizations correspond to different physical regimes of overshooting, depending on whether the effects of radiation are dominant, marginal, or negligible. Our analysis is based on previously published theoretical results, as well as on multidimensional hydrodynamical simulations of stellar convection where the interaction between the convective region and a stably stratified region is observed. Although the underlying hydrodynamical processes are the same, the outcome of the overshooting process is profoundly affected by radiative effects. Using a simple picture of the scales involved in the overshooting process, we show how three regimes are obtained, depending on the importance of radiative effects. These three regimes correspond to the different behaviors observed in hydrodynamical simulations so far and to the three types of parametrizations used in 1D codes. We suggest that the existing parametrizations for overshooting should coexist in 1D stellar evolution codes and should be applied consistently at convective boundaries depending on the local physical conditions.

  18. Altered expression profile of renal α(1D)-adrenergic receptor in diabetes and its modulation by PPAR agonists.

    PubMed

    Zhao, Xueying; Zhang, Yuanyuan; Leander, Michelle; Li, Lingyun; Wang, Guoshen; Emmett, Nerimiah

    2014-01-01

    Alpha(1D)-adrenergic receptor (α(1D)-AR) plays important roles in regulating physiological and pathological responses mediated by catecholamines, particularly in the cardiovascular and urinary systems. The present study was designed to investigate the expression profile of α(1D)-AR in the diabetic kidneys and its modulation by activation of peroxisome proliferator-activated receptors (PPARs). 12-week-old Zucker lean (ZL) and Zucker diabetic fatty (ZD) rats were treated with fenofibrate or rosiglitazone for 8-10 weeks. Gene microarray, real-time PCR, and confocal immunofluorescence microscopy were performed to assess mRNA and protein expression of α(1D)-AR in rat kidney tissue. Using microarray, we found that α(1D)-AR gene was dramatically upregulated in 22-week-old ZD rats compared to ZL controls. Quantitative PCR analysis verified a 16-fold increase in α(1D)-AR mRNA in renal cortex from ZD animals compared to normal controls. Chronic treatment with fenofibrate or rosiglitazone reduced renal cortical α(1D)-AR gene. Immunofluorescence staining confirmed that α(1D)-AR protein was induced in the glomeruli and tubules of diabetic rats. Moreover, dual immunostaining for α(1D)-AR and kidney injury molecule-1 indicated that α(1D)-AR was expressed in dedifferentiated proximal tubules of diabetic Zucker rats. Taken together, our results show that α(1D)-AR expression is upregulated in the diabetic kidneys. PPAR activation suppressed renal expression of α(1D)-AR in diabetic nephropathy.

  19. Hydrothermally processed 1D hydroxyapatite: Mechanism of formation and biocompatibility studies.

    PubMed

    Stojanović, Zoran S; Ignjatović, Nenad; Wu, Victoria; Žunič, Vojka; Veselinović, Ljiljana; Škapin, Srečo; Miljković, Miroslav; Uskoković, Vuk; Uskoković, Dragan

    2016-11-01

    Recent developments in bone tissue engineering have led to an increased interest in one-dimensional (1D) hydroxyapatite (HA) nano- and micro-structures such as wires, ribbons and tubes. They have been proposed for use as cell substrates, reinforcing phases in composites and carriers for biologically active substances. Here we demonstrate the synthesis of 1D HA structures using an optimized, urea-assisted, high-yield hydrothermal batch process. The one-pot process, yielding HA structures composed of bundles of ribbons and wires, was typified by the simultaneous occurrence of a multitude of intermediate reactions, failing to meet the uniformity criteria over particle morphology and size. To overcome these issues, the preparation procedure was divided to two stages: dicalcium phosphate platelets synthesized in the first step were used as a precursor for the synthesis of 1D HA in the second stage. Despite the elongated particle morphologies, both the precursor and the final product exhibited excellent biocompatibility and caused no reduction of viability when tested against osteoblastic MC3T3-E1 cells in 2D culture up to the concentration of 2.6mg/cm(2). X-ray powder diffraction combined with a range of electron microscopies and laser diffraction analyses was used to elucidate the formation mechanism and the microstructure of the final particles. The two-step synthesis involved a more direct transformation of DCP to 1D HA with the average diameter of 37nm and the aspect ratio exceeding 100:1. The comparison of crystalline domain sizes along different crystallographic directions showed no signs of significant anisotropy, while indicating that individual nanowires are ordered in bundles in the b crystallographic direction of the P63/m space group of HA. Intermediate processes, e.g., dehydration of dicalcium phosphate, are critical for the formation of 1D HA alongside other key aspects of this phase transformation, it must be investigated in more detail in the continuous

  20. Hydrothermally processed 1D hydroxyapatite: Mechanism of formation and biocompatibility studies.

    PubMed

    Stojanović, Zoran S; Ignjatović, Nenad; Wu, Victoria; Žunič, Vojka; Veselinović, Ljiljana; Škapin, Srečo; Miljković, Miroslav; Uskoković, Vuk; Uskoković, Dragan

    2016-11-01

    Recent developments in bone tissue engineering have led to an increased interest in one-dimensional (1D) hydroxyapatite (HA) nano- and micro-structures such as wires, ribbons and tubes. They have been proposed for use as cell substrates, reinforcing phases in composites and carriers for biologically active substances. Here we demonstrate the synthesis of 1D HA structures using an optimized, urea-assisted, high-yield hydrothermal batch process. The one-pot process, yielding HA structures composed of bundles of ribbons and wires, was typified by the simultaneous occurrence of a multitude of intermediate reactions, failing to meet the uniformity criteria over particle morphology and size. To overcome these issues, the preparation procedure was divided to two stages: dicalcium phosphate platelets synthesized in the first step were used as a precursor for the synthesis of 1D HA in the second stage. Despite the elongated particle morphologies, both the precursor and the final product exhibited excellent biocompatibility and caused no reduction of viability when tested against osteoblastic MC3T3-E1 cells in 2D culture up to the concentration of 2.6mg/cm(2). X-ray powder diffraction combined with a range of electron microscopies and laser diffraction analyses was used to elucidate the formation mechanism and the microstructure of the final particles. The two-step synthesis involved a more direct transformation of DCP to 1D HA with the average diameter of 37nm and the aspect ratio exceeding 100:1. The comparison of crystalline domain sizes along different crystallographic directions showed no signs of significant anisotropy, while indicating that individual nanowires are ordered in bundles in the b crystallographic direction of the P63/m space group of HA. Intermediate processes, e.g., dehydration of dicalcium phosphate, are critical for the formation of 1D HA alongside other key aspects of this phase transformation, it must be investigated in more detail in the continuous

  1. HLA class II susceptibility pattern for type 1 diabetes (T1D) in an Iranian population.

    PubMed

    Kiani, J; Hajilooi, M; Furst, D; Rezaei, H; Shahryari-Hesami, S; Kowsarifard, S; Zamani, A; Solgi, G

    2015-08-01

    This study aimed to determine the HLA-DRB1/HLA-DQB1 susceptibility and protection pattern for type 1 diabetes (T1D) in a population from Hamadan, north-west of Iran. A total of 133 patients with T1D were tested for HLA-DRB1 and HLA-DQB1 alleles using PCR-SSP compared to 100 ethnic-matched healthy controls. Alleles and haplotypes frequencies were compared between both groups. The most susceptible alleles for disease were HLA-DRB1*03:01, DRB1*04:02, DQB1*02:01 and DQB1*03:02, and protective alleles were HLA-DRB1*07:01, *11:01, *13:01, *14:01 and DRB1*15 and HLA-DQB1*06:01, *06:02 and *06:03. Haplotype analysis revealed that patients with T1D had higher frequencies of DRB1*03:01-DQB1*02:01 (OR = 4.86, P < 10(-7) ) and DRB1*04:02-DQB1*03:02 (OR = 9.93, P < 10(-7) ) and lower frequencies of DRB1*07:01-DQB1*02:01 (P = 0.0005), DRB1*11:01-DQB1*03:01 (P = 0.001), DRB1*13:01-DQB1*06:03 (P = 0.002) and DRB1*15-DQB1*06:01 (P = 0.001) haplotypes compared to healthy controls. Heterozygote combination of both susceptible haplotypes (DR3/DR4) confers the highest risk for T1D (RR = 18.80, P = 4 × 10(-5) ). Additionally, patients with homozygote diplotype, DR3/DR3 and DR4/DR4, showed a similar risk with less extent to heterozygote combination (P = 0.0004 and P = 0.01, respectively). Our findings not only confirm earlier reports from Iranians but also are in line with Caucasians and partly with Asians and some African patients with T1D. Remarkable differences were the identification of DRB1*04:01-DQB1*03:02, DRB1*07:01-DQB1*03:03 and DRB1*16-DQB1*05:02 as neutral and DRB1*13:01-DQB1*06:03 as the most protective haplotypes in this study.

  2. Syntheses, structures, and photoluminescence of d 10 coordination architectures: From 1D to 3D complexes based on mixed ligands

    NASA Astrophysics Data System (ADS)

    Yuan, Gang; Shao, Kui-Zhan; Du, Dong-Ying; Wang, Xin-Long; Su, Zhong-Min

    2011-05-01

    Six new compounds, namely, {[Cd 3(Himpy) 3(tda) 2]·3H 2O} n ( 1), {[Zn 3(bipy) 2(tda) 2(H 2O) 2]·4H 2O} n ( 2), {[Cd 3(bipy) 3(tda) 2]·4H 2O} n ( 3), {[Cd 3(tda) 2(H 2O) 3Cl]·H 2O} n ( 4), {[Zn 2(tz)(tda)(H 2O) 2]·H 2O} n ( 5) and {[Cd 7(pz)(tda) 4(OAc)(H 2O) 7]·3H 2O} n ( 6) [H 3tda = 1H-1,2,3-triazole-4,5-dicarboxylic acid, Himpy = 2-(1H-imidazol-2-yl)pyridine, bipy = 2,2'-bipyridine, Htz = 1H-1,2,4-triazole, H 2pz = piperazine] have been prepared under hydrothermal condition and characterized by elemental analyses, infrared spectroscopy, powder X-ray diffraction and single-crystal X-ray diffraction analyses. Compound 1 is a 1D column-like structure and displays a 3D supramolecular network via the π···π stacking interaction. The compounds 2 and 3 exhibit similar 2D layer-like structure, which further extend to 3D supermolecular structure by the π···π stacking interaction. All of compounds 4- 6 display 3D framework with diverse topology constructed from the tda 3- ligands in different coordination modes and secondary ligands (or bridging atom) connecting metal ions. Furthermore, the thermal stabilities and photoluminescent properties of compounds 1- 6 were studied.

  3. Regulation of inflorescence branch development in rice through a novel pathway involving the pentatricopeptide repeat protein sped1-D.

    PubMed

    Jiang, Guanghuai; Xiang, Yanghai; Zhao, Jiying; Yin, Dedong; Zhao, Xianfeng; Zhu, Lihuang; Zhai, Wenxue

    2014-08-01

    Panicle type has a direct bearing on rice yield. Here, we characterized a rice clustered-spikelet mutant, sped1-D, with shortened pedicels and/or secondary branches, which exhibits decreased pollen fertility. We cloned sped1-D and found that it encodes a pentatricopeptide repeat protein. We investigated the global expression profiles of wild-type, 9311, and sped1-D plants using Illumina RNA sequencing. The expression of several GID1L2 family members was downregulated in the sped1-D mutant, suggesting that the gibberellin (GA) pathway is involved in the elongation of pedicels and/or secondary branches. When we overexpressed one GID1L2, AK070299, in sped1-D plants, the panicle phenotype was restored to varying degrees. In addition, we analyzed the expression of genes that function in floral meristems and found that RFL and WOX3 were severely downregulated in sped1-D. These results suggest that sped1-D may prompt the shortening of pedicels and secondary branches by blocking the action of GID1L2, RFL, and Wox3. Moreover, overexpression of sped1-D in Arabidopsis resulted in the shortening of pedicels and clusters of siliques, which indicates that the function of sped1-D is highly conserved in monocotyledonous and dicotyledonous plants. Sequence data from this article have been deposited with the miRBase Data Libraries under accession no. MI0003201.

  4. 1D coordination polymers formed by tetranuclear lead(II) building blocks with carboxylate ligands: In situ isomerization of itaconic acid

    SciTech Connect

    Rana, Abhinandan; Jana, Swapan Kumar; Datta, Sayanti; Butcher, Raymond J.; Zangrando, Ennio; Dalai, Sudipta

    2013-11-15

    The synthesis of two new lead(II) coordination polymers, [Pb{sub 2}(mpic){sub 4}(H{sub 2}O)]·0.5H{sub 2}O (1) and [Pb{sub 2}(phen){sub 2}(cit)(mes)]·2H{sub 2}O (2) has been reported, where mpic=3-methyl picolinate, phen=o-phenanthroline, H{sub 2}cit=citraconic acid, H{sub 2}mes mesaconic acid. X-ray single crystal diffraction analyses showed that the complexes comprise topologically different 1D polymeric chains stabilized by weak interactions and both containing tetranuclear Pb{sub 4} units connected by carboxylate groups. In compound 1 3-methylpicolinic acid is formed in situ from 3-methyl piconitrile, and mesaconate and citraconate anions were surprisingly formed from itaconic acid during the synthesis of 2. The photoluminescence and thermal properties of the complexes have been studied. - Graphical abstract: Two new topologically different 1D coordination polymers formed by Pb{sub 4} clusters have been synthesized and characterized by X-ray analysis. The luminescence and thermal properties have been studied. Display Omitted - Highlights: • Both the complexes, made up of different ligands, forms topologycally different 1D polymeric chains containing Pb{sub 4} clusters. • The final structures are stabilized by weak interactions (H-bond, π∙∙∙π stacking). • In complex 1, the 3-methylpicolinic acid is generated in situ from 3-methyl piconitrile. • Mesaconate and citraconate anions are surprisingly formed in situ from itaconic acid during the synthesis of complex 2, indicating an exceptional transformation.

  5. Nested 1D-2D approach for urban surface flood modeling

    NASA Astrophysics Data System (ADS)

    Murla, Damian; Willems, Patrick

    2015-04-01

    Floods in urban areas as a consequence of sewer capacity exceedance receive increased attention because of trends in urbanization (increased population density and impermeability of the surface) and climate change. Despite the strong recent developments in numerical modeling of water systems, urban surface flood modeling is still a major challenge. Whereas very advanced and accurate flood modeling systems are in place and operation by many river authorities in support of flood management along rivers, this is not yet the case in urban water management. Reasons include the small scale of the urban inundation processes, the need to have very high resolution topographical information available, and the huge computational demands. Urban drainage related inundation modeling requires a 1D full hydrodynamic model of the sewer network to be coupled with a 2D surface flood model. To reduce the computational times, 0D (flood cones), 1D/quasi-2D surface flood modeling approaches have been developed and applied in some case studies. In this research, a nested 1D/2D hydraulic model has been developed for an urban catchment at the city of Gent (Belgium), linking the underground sewer (minor system) with the overland surface (major system). For the overland surface flood modelling, comparison was made of 0D, 1D/quasi-2D and full 2D approaches. The approaches are advanced by considering nested 1D-2D approaches, including infiltration in the green city areas, and allowing the effects of surface storm water storage to be simulated. An optimal nested combination of three different mesh resolutions was identified; based on a compromise between precision and simulation time for further real-time flood forecasting, warning and control applications. Main streets as mesh zones together with buildings as void regions constitute one of these mesh resolution (3.75m2 - 15m2); they have been included since they channel most of the flood water from the manholes and they improve the accuracy of

  6. Biological Macromolecule Crystallization Database

    National Institute of Standards and Technology Data Gateway

    SRD 21 Biological Macromolecule Crystallization Database (Web, free access)   The Biological Macromolecule Crystallization Database and NASA Archive for Protein Crystal Growth Data (BMCD) contains the conditions reported for the crystallization of proteins and nucleic acids used in X-ray structure determinations and archives the results of microgravity macromolecule crystallization studies.

  7. 1D-3D registration for intra-operative nuclear imaging in radio-guided surgery.

    PubMed

    Vetter, Christoph; Lasser, Tobias; Okur, Asli; Navab, Nassir

    2015-02-01

    3D functional nuclear imaging modalities like SPECT or PET provide valuable information, as small structures can be marked with radioactive tracers to be localized before surgery. This positional information is valuable during surgery as well, for example when locating potentially cancerous lymph nodes in the case of breast cancer. However, the volumetric information provided by pre-operative SPECT scans loses validity quickly due to posture changes and manipulation of the soft tissue during surgery. During the intervention, the surgeon has to rely on the acoustic feedback provided by handheld gamma-detectors in order to localize the marked structures. In this paper, we present a method that allows updating the pre-operative image with a very limited number of tracked readings. A previously acquired 3D functional volume serves as prior knowledge and a limited number of new 1D detector readings is used in order to update the prior knowledge. This update is performed by a 1D-3D registration algorithm that registers the volume to the detector readings. This enables the rapid update of the visual guidance provided to the surgeon during a radio-guided surgery without slowing down the surgical workflow. We evaluate the performance of this approach using Monte-Carlo simulations, phantom experiments and patient data, resulting in a positional error of less than 8 mm which is acceptable for surgery. The 1D-3D registration is also compared to a volumetric reconstruction using the tracked detector measurements without taking prior information into account, and achieves a comparable accuracy with significantly less measurements.

  8. Universal low-energy physics in 1D strongly repulsive multi-component Fermi gases

    NASA Astrophysics Data System (ADS)

    Jiang, Yuzhu; He, Peng; Guan, Xi-Wen

    2016-04-01

    It has been shown (Yang and You 2011 Chin. Phys. Lett. 28 020503) that at zero temperature the ground state of the one-dimensional (1D) w-component Fermi gas coincides with that of the spinless Bose gas in the limit ω \\to ∞ . This behavior was experimentally evidenced through quasi-1D tightly trapping ultracold 173Yb atoms in a recent paper (Pagano et al 2014 Nat. Phys. 10 198). However, understanding of low-temperature behavior of Fermi gases with a repulsive interaction requires spin-charge separated conformal field theories of an effective Tomonaga-Luttinger liquid and an antiferromagnetic SU(w) Heisenberg spin chain. Here we analytically derive universal thermodynamics of 1D strongly repulsive fermionic gases with SU(w) symmetry via the Yang-Yang thermodynamic Bethe ansatz method. The analytical free energy and magnetic properties of the systems at low temperature in a weak magnetic field are obtained through the Wiener-Hopf method. In particular, the free energy essentially manifests the spin-charge separated conformal field theories for high-symmetry systems with arbitrary repulsive interaction strength. We also find that the sound velocity of the Fermi gases in the large w limit coincides with that for the spinless Bose gas, whereas the spin velocity vanishes quickly as w becomes large. This indicates strong suppression of the Fermi exclusion statistics by the commutativity feature among the w-component fermions with different spin states in the Tomonaga-Luttinger liquid phase. Moreover, the equations of state and critical behavior of physical quantities at finite temperature are analytically derived in terms of the polylogarithm functions in the quantum critical region.

  9. Supersymmetric configurations in the rotating D1-D5 system andpp-waves

    NASA Astrophysics Data System (ADS)

    Maoz, Liat

    Two families of supersymmetric configurations are considered. One is the 1/4 supersymmetric D1--D5 system with angular momentum, and the other is a family of pp-waves of type IIB string theory with some supersymmetry. In the first part of the thesis some configurations of the D1--D5 system are examined which give conical singularities in AdS 3 as their near horizon limit. It is shown that they can be made non-singular by adding angular momentum to the brane system. The smooth asymptotically flat solutions constructed this way are used to obtain global AdS 3 as the near horizon geometry. Using the relation of the D1--D5 system to the oscillating string, a large family of supergravity solutions is constructed which describe BPS excitations on AdS3 x S 3 with angular momentum on S3. These solutions take into account the full back reaction on the metric, and can be viewed as Kaluza-Klein monopole "supertubes", which are completely non-singular geometries. The different chiral primaries of the dual CFT are identified with these different supergravity solutions. This part is adapted from the papers [1], [2]. In its second part, a general class of supersymmetric pp-wave solutions of type IIB string theory is constructed, such that the superstring worldsheet action in light cone gauge is that of an interacting massive field theory. It is shown that when the light cone Lagrangian has (2.2) supersymmetry, one can find backgrounds that lead to arbitrary superpotentials on the worldsheet. Both flat and curved transverse spaces are considered. In particular, the background giving rise to the N = 2 sine Gordon theory on the worldsheet is analyzed. Massive mirror symmetry relates it to the deformed CP1 model (or sausage model) which seems to elude a purely supergravity target space interpretation. These are results which appeared in the paper [3].

  10. Assessment and improvement of the 2D/1D method stability in DeCART

    SciTech Connect

    Stimpson, S.; Young, M.; Collins, B.; Kelley, B.; Downar, T.

    2013-07-01

    As part of ongoing work with Consortium for Advanced Simulation of Light Water Reactors (CASL), the 2D/1D code, DeCART, has demonstrated some of the advantages of the 2D/1D method with respect to realistic, full-core analysis, particularly over explicit 3D transport methods, which generally have higher memory and computation requirements. The 2D/1D method performs 2D-radial transport sweeps coupled with ID-axial diffusion calculations to provide a full 3D simulation. DeCART employs the 2D method of characteristics for the radial sweeps and ID one-node nodal diffusion for the axial sweeps, coupling the two methods with transverse leakages to ensure a more consistent representation of the transport equation. It has been observed that refinement of the axial plane thickness leads to instabilities in the calculation scheme. This work assesses the sources of these instabilities and the approaches to improve them, especially with respect to negative scattering cross sections and the tightness of the 2D-radial/ID-axial coupling schemes. Fourier analyses show that the existing iteration scheme is not unconditionally stable, suggesting a tighter coupling scheme is required. For this reason 3D-CMFD has been implemented, among other developments, to ensure more stable calculation. A matrix of test cases has been used to assess the convergence, with the primary parameter being the axial plane thickness, which has been refined down to 1 cm. These cases demonstrate the issues observed and how the modification improve the stability. However, it is apparent that more work is necessary to ensure unconditional stability. (authors)

  11. Review of Zero-D and 1-D Models of Blood Flow in the Cardiovascular System

    PubMed Central

    2011-01-01

    Background Zero-dimensional (lumped parameter) and one dimensional models, based on simplified representations of the components of the cardiovascular system, can contribute strongly to our understanding of circulatory physiology. Zero-D models provide a concise way to evaluate the haemodynamic interactions among the cardiovascular organs, whilst one-D (distributed parameter) models add the facility to represent efficiently the effects of pulse wave transmission in the arterial network at greatly reduced computational expense compared to higher dimensional computational fluid dynamics studies. There is extensive literature on both types of models. Method and Results The purpose of this review article is to summarise published 0D and 1D models of the cardiovascular system, to explore their limitations and range of application, and to provide an indication of the physiological phenomena that can be included in these representations. The review on 0D models collects together in one place a description of the range of models that have been used to describe the various characteristics of cardiovascular response, together with the factors that influence it. Such models generally feature the major components of the system, such as the heart, the heart valves and the vasculature. The models are categorised in terms of the features of the system that they are able to represent, their complexity and range of application: representations of effects including pressure-dependent vessel properties, interaction between the heart chambers, neuro-regulation and auto-regulation are explored. The examination on 1D models covers various methods for the assembly, discretisation and solution of the governing equations, in conjunction with a report of the definition and treatment of boundary conditions. Increasingly, 0D and 1D models are used in multi-scale models, in which their primary role is to provide boundary conditions for sophisticate, and often patient-specific, 2D and 3D models

  12. Synthesis, Characterization, and Application of 1-D Cerium Oxide Nanomaterials: A Review

    PubMed Central

    Lin, Kuen-Song; Chowdhury, Sujan

    2010-01-01

    The present work provides a comprehensive overview of the recent progress of research work toward developing new one dimensional (1-D) ceria (CeO2) nanomaterials. The review has been classified into three parts: the preparation procedures with identification of the existing different dimensional ceria nanomaterials, the formation mechanisms, and an analysis of their applications. From literature survey, it is inaugurated that the fundamental structures of the ceria nanomaterials constructively dominate their properties and applications. In addition, this work will also provide a perspective on the future technical trends for the development of different dimensional CeO2 nanomaterials. PMID:20957090

  13. Formation of Molecules near a Feshbach Resonance in a 1D Optical Lattice

    SciTech Connect

    Orso, G.; Pitaevskii, L.P.; Stringari, S.; Wouters, M.

    2005-08-05

    We study the molecular behavior of two atoms interacting near a Feshbach resonance in the presence of a 1D periodic potential. The critical value of the scattering length needed to produce a molecule and the binding energy at resonance are calculated as a function of the intensity of the periodic potential. Because of the nonseparability of the center of mass and relative motion, the binding energy depends on the quasimomentum of the molecule. This has dramatic consequences on the molecular tunneling properties, which become strongly dependent on the scattering length.

  14. Thermodynamic nature of vitrification in a 1D model of a structural glass former

    SciTech Connect

    Semenov, A. N.

    2015-07-28

    We propose a new spin-glass model with no positional quenched disorder which is regarded as a coarse-grained model of a structural glass-former. The model is analyzed in the 1D case when the number N of states of a primary cell is large. For N → ∞, the model exhibits a sharp freezing transition of the thermodynamic origin. It is shown both analytically and numerically that the glass transition is accompanied by a significant growth of a static length scale ξ pointing to the structural (equilibrium) nature of dynamical slowdown effects in supercooled liquids.

  15. Hair on non-extremal D1-D5 bound states

    NASA Astrophysics Data System (ADS)

    Roy, Pratik; Srivastava, Yogesh K.; Virmani, Amitabh

    2016-09-01

    We consider a truncation of type IIB supergravity on four-torus where in addition to the Ramond-Ramond 2-form field, the Ramond-Ramond axion ( w) and the NS-NS 2-form field ( B) are also retained. In the ( w, B) sector we construct a linearised perturbation carrying only left moving momentum on two-charge non-extremal D1-D5 geometries of Jejjala, Madden, Ross and Titchener. The perturbation is found to be smooth everywhere and normalisable. It is constructed by matching to leading order solutions of the perturbation equations in the inner and outer regions of the geometry.

  16. Delocalization of Weakly Interacting Bosons in a 1D Quasiperiodic Potential

    NASA Astrophysics Data System (ADS)

    Michal, V. P.; Altshuler, B. L.; Shlyapnikov, G. V.

    2014-07-01

    We consider weakly interacting bosons in a 1D quasiperiodic potential (Aubry-Azbel-Harper model) in the regime where all single-particle states are localized. We show that the interparticle interaction may lead to the many-body delocalization and we obtain the finite-temperature phase diagram. Counterintuitively, in a wide range of parameters the delocalization requires stronger coupling as the temperature increases. This means that the system of bosons can undergo a transition from a fluid to insulator (glass) state under heating.

  17. Analytic solutions for the approximated 1-D Monge-Kantorovich mass transfer problems

    NASA Astrophysics Data System (ADS)

    Lu, Xiaojun; Lv, Xiaofen

    2016-10-01

    This paper mainly investigates the approximation of a global maximizer of the 1-D Monge-Kantorovich mass transfer problem through the approach of nonlinear differential equations with Dirichlet boundary. Using an approximation mechanism, the primal maximization problem can be transformed into a sequence of minimization problems. By applying the canonical duality theory, one is able to derive a sequence of analytic solutions for the minimization problems. In the final analysis, the convergence of the sequence to a global maximizer of the primal Monge-Kantorovich problem will be demonstrated.

  18. Thermodynamic nature of vitrification in a 1D model of a structural glass former.

    PubMed

    Semenov, A N

    2015-07-28

    We propose a new spin-glass model with no positional quenched disorder which is regarded as a coarse-grained model of a structural glass-former. The model is analyzed in the 1D case when the number N of states of a primary cell is large. For N → ∞, the model exhibits a sharp freezing transition of the thermodynamic origin. It is shown both analytically and numerically that the glass transition is accompanied by a significant growth of a static length scale ξ pointing to the structural (equilibrium) nature of dynamical slowdown effects in supercooled liquids. PMID:26233148

  19. The 1D Kardar-Parisi-Zhang equation: Height distribution and universality

    NASA Astrophysics Data System (ADS)

    Sasamoto, Tomohiro

    2016-02-01

    The Kardar-Parisi-Zhang (KPZ) equation, which was introduced in 1986 as a model equation to describe the dynamics of an interface motion, has been attracting renewed interest in recent years. In particular, the height distribution of its 1D version was determined exactly for a few special initial conditions. Its relevance in experiments was demonstrated and our understanding of the mathematical structures behind its tractability has deepened considerably. There are also new developments in the applicability of the KPZ universality in wider contexts. This paper is a short introductory review on the basics of the equation and on a few recent topics.

  20. Scratched-XY Universality and Phase Diagram of Disordered 1D Bosons in Optical Lattice

    NASA Astrophysics Data System (ADS)

    Yao, Zhiyuan; Pollet, Lode; Prokof'ev, Nikolay; Svistunov, Boris

    The superfluid-insulator quantum phase transition in a 1D system with weak links belongs to the so-called scratched-XY universality class, provided the irrenormalizable exponent ζ characterizing the distribution of weak links is smaller than 2 / 3 . With a combination of worm-algorithm Monte Carlo simulations and asymptotically exact analytics, we accurately trace the position of the scratched-XY critical line on the ground-state phase diagram of bosonic Hubbard model at unity filling. In particular, we reveal the location of the tricritical point separating the scratched-XY criticality from the Giamarchi-Schulz one.

  1. Effect of low transverse magnetic field on the confinement strength in a quasi-1D wire

    SciTech Connect

    Kumar, Sanjeev; Thomas, K. J.; Smith, L. W.; Farrer, I.; Ritchie, D. A.; Jones, G. A. C.; Griffiths, J.; Pepper, M.

    2013-12-04

    Transport measurements in a quasi-one dimensional (1D) quantum wire are reported in the presence of low transverse magnetic field. Differential conductance shows weak quantised plateaus when the 2D electrons are squeezed electrostatically. Application of a small transverse magnetic field (0.2T) enhances the overall degree of quantisation due to the formation of magneto-electric subbands. The results show the role of magnetic field to fine tune the confinement strength in low density wires when interaction gives rise to double row formation.

  2. Phase-Sensitive Detection of Bragg Scattering at 1D Optical Lattices

    SciTech Connect

    Slama, S.; Cube, C. von; Deh, B.; Ludewig, A.; Zimmermann, C.; Courteille, Ph.W.

    2005-05-20

    We report on the observation of Bragg scattering at 1D atomic lattices. Cold atoms are confined by optical dipole forces at the antinodes of a standing wave generated by the two counterpropagating modes of a laser-driven high-finesse ring cavity. By heterodyning the Bragg-scattered light with a reference beam, we obtain detailed information on phase shifts imparted by the Bragg scattering process. Being deep in the Lamb-Dicke regime, the scattered light is not broadened by the motion of individual atoms.

  3. Simulations of Edge Effect in 1D Spin Crossover Compounds by Atom-Phonon Coupling Model

    NASA Astrophysics Data System (ADS)

    Linares, J.; Chiruta, D.; Jureschi, C. M.; Alayli, Y.; Turcu, C. O.; Dahoo, P. R.

    2016-08-01

    We used the atom-phonon coupling model to explain and illustrate the behaviour of a linear nano-chain of molecules. The analysis of the system's behaviour was performed using Free Energy method, and by applying Monte Carlo Metropolis (MCM) method which take into account the phonon contribution. In particular we tested both the MCM algorithm and the dynamic-matrix method and we expose how the thermal behaviour of a 1D spin crossover system varies as a function of different factors. Furthermore we blocked the edge atoms of the chain in its high spin state to study the effect on the system's behaviour.

  4. Injectable composites via functionalization of 1D nanoclays and biodegradable coupling with a polysaccharide hydrogel.

    PubMed

    Del Buffa, Stefano; Rinaldi, Elia; Carretti, Emiliano; Ridi, Francesca; Bonini, Massimo; Baglioni, Piero

    2016-09-01

    The use of injectable materials in minimally invasive surgical procedures could help in facing the bone diseases connected to the ageing of world population. To this aim, materials integrating the rheological properties of biocompatible polymers with the mechanical properties of 1D inorganic nanostructures represent promising scaffolds. Here we describe the preparation of hydrogel composites made of carboxymethyl cellulose (CMC) and halloysite nanotubes (HNT) as injectable materials for the local treatment of bone defects. The rheology and injectability of the materials reflects their structural properties, showing the possibility of successfully injecting the prepared composites over a large range of operative conditions.

  5. Almost ideal 1D water diffusion in imogolite nanotubes evidenced by NMR relaxometry.

    PubMed

    Belorizky, Elie; Fries, Pascal H; Guillermo, Armel; Poncelet, Olivier

    2010-06-21

    The longitudinal proton relaxation rates R(1) of water diffusing inside synthetic aluminium silicate imogolite nanotubes are measured by fast field-cycling NMR for frequencies between 0.02 and 35 MHz at 25, 37 and 50 degrees C. We give analytical expressions of the dominant intermolecular dipolar spin-spin contribution to R(1) and to the transverse relaxation rate R(2). A remarkable variation of R(1) by more than two orders of magnitude is observed and shown to be close to the theoretical law, inversely proportional to the square root of the resonance frequency, which is characteristic of perfect molecular 1D diffusion. The physics of diffusion is discussed.

  6. Pharmacological evidence that 5-HT1D activation induces renal vasodilation by NO pathway in rats.

    PubMed

    García-Pedraza, José-Ángel; García, Mónica; Martín, María-Luisa; Morán, Asunción

    2015-06-01

    5-HT is a powerful vasoconstrictor substance in renal vasculature (mainly by 5-HT₂ activation). Nevertheless, 5-HT is notable for its dual cardiovascular effects, producing both vasodilator and vasoconstrictor actions. This study aimed to investigate whether, behind the predominant serotonergic vasoconstrictor action, THE 5-HT system may exert renal vasodilator actions, and, if so, characterize the 5-HT receptors and possible indirect pathways. Renal perfusion pressure (PP), systemic blood pressure (SBP) and heart rate (HR) measurement in in situ autoperfused rat kidney was determined in phenylephrine infused rats. Intra arterial (i.a.) bolus administration of 5-HT (0.00000125-0.1 μg/kg) decreased renal PP in the presence of a phenylephrine continuous infusion (phenylephrine-infusion group), without modifying SBP or HR. These vasodilator responses were potentiated by 5-HT₂ antagonism (ritanserin, 1 mg/kg i.v.), whereas the responses were abolished by 5-HT₁ /₇ antagonist (methiothepin, 100 μg/kg i.v.) or 5-HT1D antagonist (LY310762, 1 mg/kg i.v.). The i.a. administration (0.00000125 to 0.1 μg/kg) of 5-CT or L-694,247 (5-HT1D agonist) mimicked 5-HT vasodilator effect, while other agonists (1-PBG, α-methyl-5-HT, AS-19 (5-HT₇), 8-OH-DPAT (5-HT1A) or CGS-12066B (5-HT1B)) did not alter baseline haemodynamic variables. L-694,247 vasodilation was abolished by i.v. bolus of antagonists LY310762 (5-HT1D, 1 mg/kg) or L-NAME (nitric oxide, 10 mg/kg), but not by i.v. bolus of indomethacin (cyclooxygenase, 2 mg/kg) or glibenclamide (ATP-dependent K(+) channel, 20 mg/kg). These outcomes suggest that 5-HT1D activation produces a vasodilator effect in the in situ autoperfused kidney of phenylephrine-infusion rats mediated by the NO pathway. PMID:25854421

  7. 2D ESR image reconstruction from 1D projections using the modulated field gradient method

    NASA Astrophysics Data System (ADS)

    Páli, T.; Sass, L.; Horvat, L. I.; Ebert, B.

    A method for the reconstruction of 2D ESR images from 1 D projections which is based on the modulated field gradient method has been explored. The 2D distribution of spin-labeled stearic acid in oriented and unoriented dimyristoyl phosphatidylcholine multilayers on a flat quartz support was determined. Such samples are potentially useful for the determination of lipid lateral diffusion in oriented multilayers by monitoring the spreading of a sharp concentration profile in one or two dimensions. The limitations of the method are discussed and the improvements which are needed for dynamic measurements are outlined.

  8. Exponentially-convergent Monte Carlo for the 1-D transport equation

    SciTech Connect

    Peterson, J. R.; Morel, J. E.; Ragusa, J. C.

    2013-07-01

    We define a new exponentially-convergent Monte Carlo method for solving the one-speed 1-D slab-geometry transport equation. This method is based upon the use of a linear discontinuous finite-element trial space in space and direction to represent the transport solution. A space-direction h-adaptive algorithm is employed to restore exponential convergence after stagnation occurs due to inadequate trial-space resolution. This methods uses jumps in the solution at cell interfaces as an error indicator. Computational results are presented demonstrating the efficacy of the new approach. (authors)

  9. Prediction of car cabin environment by means of 1D and 3D cabin model

    NASA Astrophysics Data System (ADS)

    Fišer, J.; Pokorný, J.; Jícha, M.

    2012-04-01

    Thermal comfort and also reduction of energy requirements of air-conditioning system in vehicle cabins are currently very intensively investigated and up-to-date issues. The article deals with two approaches of modelling of car cabin environment; the first model was created in simulation language Modelica (typical 1D approach without cabin geometry) and the second one was created in specialized software Theseus-FE (3D approach with cabin geometry). Performance and capabilities of this tools are demonstrated on the example of the car cabin and the results from simulations are compared with the results from the real car cabin climate chamber measurements.

  10. KAM Tori for 1D Nonlinear Wave Equationswith Periodic Boundary Conditions

    NASA Astrophysics Data System (ADS)

    Chierchia, Luigi; You, Jiangong

    In this paper, one-dimensional (1D) nonlinear wave equations with periodic boundary conditions are considered; V is a periodic smooth or analytic function and the nonlinearity f is an analytic function vanishing together with its derivative at u≡0. It is proved that for ``most'' potentials V(x), the above equation admits small-amplitude periodic or quasi-periodic solutions corresponding to finite dimensional invariant tori for an associated infinite dimensional dynamical system. The proof is based on an infinite dimensional KAM theorem which allows for multiple normal frequencies.

  11. 75 FR 3159 - Corporate Reorganizations; Distributions Under Sections 368(a)(1)(D) and 354(b)(1)(B); Correction

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-20

    ... Sections 368(a)(1)(D) and 354(b)(1)(B); Correction AGENCY: Internal Revenue Service (IRS), Treasury...) that were published in the Federal Register on Friday, December 18, 2009 (74 FR 67053) providing...)(1)(D) where no stock and/or securities of the acquiring corporation is issued and distributed in...

  12. 50 CFR Table 1d to Part 660... - At-Sea Whiting Fishery Annual Set-Asides, 2011 and 2012.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false At-Sea Whiting Fishery Annual Set-Asides, 2011 and 2012. 1d Table 1d to Part 660, Subpart C Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE (CONTINUED) FISHERIES OFF WEST COAST STATES Pt. 660, Subpt. C,...

  13. Severe hypoglycemia and diabetic ketoacidosis among youth with type 1 diabetes in the T1D Exchange clinic registry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Severe hypoglycemia (SH) and diabetic ketoacidosis (DKA) are common serious acute complications of type 1 diabetes (T1D). The aim of this study was to determine the frequency of SH and DKA and identify factors related to their occurrence in the T1D Exchange pediatric and young adult cohort. The anal...

  14. Recombinant Phage Coated 1D Al2O3 Nanostructures for Controlling the Adhesion and Proliferation of Endothelial Cells

    PubMed Central

    Lee, Juseok; Jeon, Hojeong; Haidar, Ayman; Abdul-Khaliq, Hashim; Veith, Michael; Kim, Youngjun

    2015-01-01

    A novel synthesis of a nanostructured cell adhesive surface is investigated for future stent developments. One-dimensional (1D) Al2O3 nanostructures were prepared by chemical vapor deposition of a single source precursor. Afterwards, recombinant filamentous bacteriophages which display a short binding motif with a cell adhesive peptide (RGD) on p3 and p8 proteins were immobilized on these 1D Al2O3 nanostructures by a simple dip-coating process to study the cellular response of human endothelial EA hy.926. While the cell density decreased on as-deposited 1D Al2O3 nanostructures, we observed enhanced cell proliferation and cell-cell interaction on recombinant phage overcoated 1D Al2O3 nanostructures. The recombinant phage overcoating also supports an isotropic cell spreading rather than elongated cell morphology as we observed on as-deposited Al2O3 1D nanostructures. PMID:26090458

  15. Crystallization process

    DOEpatents

    Adler, Robert J.; Brown, William R.; Auyang, Lun; Liu, Yin-Chang; Cook, W. Jeffrey

    1986-01-01

    An improved crystallization process is disclosed for separating a crystallizable material and an excluded material which is at least partially excluded from the solid phase of the crystallizable material obtained upon freezing a liquid phase of the materials. The solid phase is more dense than the liquid phase, and it is separated therefrom by relative movement with the formation of a packed bed of solid phase. The packed bed is continuously formed adjacent its lower end and passed from the liquid phase into a countercurrent flow of backwash liquid. The packed bed extends through the level of the backwash liquid to provide a drained bed of solid phase adjacent its upper end which is melted by a condensing vapor.

  16. Ribbon crystals.

    PubMed

    Bohr, Jakob; Markvorsen, Steen

    2013-01-01

    A repetitive crystal-like pattern is spontaneously formed upon the twisting of straight ribbons. The pattern is akin to a tessellation with isosceles triangles, and it can easily be demonstrated with ribbons cut from an overhead transparency. We give a general description of developable ribbons using a ruled procedure where ribbons are uniquely described by two generating functions. This construction defines a differentiable frame, the ribbon frame, which does not have singular points, whereby we avoid the shortcomings of the Frenet-Serret frame. The observed spontaneous pattern is modeled using planar triangles and cylindrical arcs, and the ribbon structure is shown to arise from a maximization of the end-to-end length of the ribbon, i.e. from an optimal use of ribbon length. The phenomenon is discussed in the perspectives of incompatible intrinsic geometries and of the emergence of long-range order.

  17. Ribbon Crystals

    PubMed Central

    Bohr, Jakob; Markvorsen, Steen

    2013-01-01

    A repetitive crystal-like pattern is spontaneously formed upon the twisting of straight ribbons. The pattern is akin to a tessellation with isosceles triangles, and it can easily be demonstrated with ribbons cut from an overhead transparency. We give a general description of developable ribbons using a ruled procedure where ribbons are uniquely described by two generating functions. This construction defines a differentiable frame, the ribbon frame, which does not have singular points, whereby we avoid the shortcomings of the Frenet–Serret frame. The observed spontaneous pattern is modeled using planar triangles and cylindrical arcs, and the ribbon structure is shown to arise from a maximization of the end-to-end length of the ribbon, i.e. from an optimal use of ribbon length. The phenomenon is discussed in the perspectives of incompatible intrinsic geometries and of the emergence of long-range order. PMID:24098360

  18. Liquid Crystal Devices.

    ERIC Educational Resources Information Center

    Bradshaw, Madeline J.

    1983-01-01

    The nature of liquid crystals and several important liquid crystal devices are described. Ideas for practical experiments to illustrate the properties of liquid crystals and their operation in devices are also described. (Author/JN)

  19. Liquid Crystal Inquiries.

    ERIC Educational Resources Information Center

    Marroum, Renata-Maria

    1996-01-01

    Discusses the properties and classification of liquid crystals. Presents a simple experiment that illustrates the structure of liquid crystals and the differences between the various phases liquid crystals can assume. (JRH)

  20. CD1d- and MR1-Restricted T Cells in Sepsis

    PubMed Central

    Szabo, Peter A.; Anantha, Ram V.; Shaler, Christopher R.; McCormick, John K.; Haeryfar, S.M. Mansour

    2015-01-01

    Dysregulated immune responses to infection, such as those encountered in sepsis, can be catastrophic. Sepsis is typically triggered by an overwhelming systemic response to an infectious agent(s) and is associated with high morbidity and mortality even under optimal critical care. Recent studies have implicated unconventional, innate-like T lymphocytes, including CD1d- and MR1-restricted T cells as effectors and/or regulators of inflammatory responses during sepsis. These cell types are typified by invariant natural killer T (iNKT) cells, variant NKT (vNKT) cells, and mucosa-associated invariant T (MAIT) cells. iNKT and vNKT cells are CD1d-restricted, lipid-reactive cells with remarkable immunoregulatory properties. MAIT cells participate in antimicrobial defense, and are restricted by major histocompatibility complex-related protein 1 (MR1), which displays microbe-derived vitamin B metabolites. Importantly, NKT and MAIT cells are rapid and potent producers of immunomodulatory cytokines. Therefore, they may be considered attractive targets during the early hyperinflammatory phase of sepsis when immediate interventions are urgently needed, and also in later phases when adjuvant immunotherapies could potentially reverse the dangerous state of immunosuppression. We will highlight recent findings that point to the significance or the therapeutic potentials of NKT and MAIT cells in sepsis and will also discuss what lies ahead in research in this area. PMID:26322041

  1. Assessment of a fast electro-optical shutter for 1D spontaneous Raman scattering in flames

    NASA Astrophysics Data System (ADS)

    Ajrouche, Hassan; Lo, Amath; Vervisch, Pierre; Cessou, Armelle

    2015-07-01

    A critical aspect of 1D single-shot spontaneous Raman scattering (SRS) experiments in turbulent flames is the need to ensure highly efficient detection associated with fast temporal gating to remove flame emission. Back-illuminated CCD cameras are remarkable for their high quantum efficiency, large dynamic range, good spatial resolution and low readout noise. However, their full-frame architecture makes these detectors difficult to use for SRS measurements in flame and requires the development of a high-speed shutter. The present work proposes a fast electro-optical shutter composed of a large aperture Pockels cell placed between two crossed polarizers, providing high-speed gating up to 500 ns. The throughput of the shutter and its spatial homogeneity are measured. The angular tolerance of the Pockels cell is determined and its suitability for 1D probing is assessed. Spectra acquired in a premixed methane-air flame show the capacity of the shutter to remove flame emission and increase the signal-to-noise ratio for major Raman species.

  2. Gap opening in graphene by 1D and 2D periodic corrugations

    NASA Astrophysics Data System (ADS)

    Naumov, Ivan; Bratkovsky, Alexander

    2012-02-01

    Using first-principles methods and symmetry arguments, we show that a graphene monolayer, which is periodically corrugated in one or two direction(s), can be either semimetal or semiconductor, depending on how strong corrugation is or how the initial symmetry is broken. In the case of 1D periodic ripples, a gap at the Dirac points opens up only due to (i) breaking of the inversion symmetry or equivalence between A and B sublattices and/or (ii) merging of two inequivalent Dirac points, D and -D. Since breaking the inversion symmetry has only relatively modest effect, a tangible gap can be mainly induced by mutual annihilation of the Dirac points, which requires large corrugations, close to mechanical breaking point. In contrast to 1D, the 2D ripples can additionally induce a semiconducting gap via mixing of electronic states belonging to two different K, K' valleys. In this case, a gap on the order of 0.5 eV can be opened up at strains safely lower than the graphene failure strain [1]. [4pt] [1] I.I. Naumov, A.M. Bratkovsky, arXiv:1104.0314v1.

  3. A facile route for 3D aerogels from nanostructured 1D and 2D materials

    PubMed Central

    Jung, Sung Mi; Jung, Hyun Young; Dresselhaus, Mildred S.; Jung, Yung Joon; Kong, Jing

    2012-01-01

    Aerogels have numerous applications due to their high surface area and low densities. However, creating aerogels from a large variety of materials has remained an outstanding challenge. Here, we report a new methodology to enable aerogel production with a wide range of materials. The method is based on the assembly of anisotropic nano-objects (one-dimensional (1D) nanotubes, nanowires, or two-dimensional (2D) nanosheets) into a cross-linking network from their colloidal suspensions at the transition from the semi-dilute to the isotropic concentrated regime. The resultant aerogels have highly porous and ultrafine three-dimensional (3D) networks consisting of 1D (Ag, Si, MnO2, single-walled carbon nanotubes (SWNTs)) and 2D materials (MoS2, graphene, h-BN) with high surface areas, low densities, and high electrical conductivities. This method opens up a facile route for aerogel production with a wide variety of materials and tremendous opportunities for bio-scaffold, energy storage, thermoelectric, catalysis, and hydrogen storage applications. PMID:23152940

  4. Superdescendants of the D1D5 CFT and their dual 3-charge geometries

    NASA Astrophysics Data System (ADS)

    Giusto, Stefano; Russo, Rodolfo

    2014-03-01

    We describe how to obtain the gravity duals of semiclassical states in the D1-D5 CFT that are superdescendants of a class of RR ground states. On the gravity side, the configurations we construct are regular and asymptotically reproduce the 3-charge D1-D5-P black hole compactified on S 1 × T 4. The geometries depend trivially on the T 4 directions but non-trivially on the remaining 6D space. In the decoupling limit, they reduce to asymptotically AdS3 × S 3 × T 4 spaces that are dual to CFT states obtained by acting with (exponentials of) the operators of the superconformal algebra. As explicit examples, we generalise the solution first constructed in arXiv:1306.1745 and discuss another class of states that have a more complicated dual geometry. By using the free orbifold description of the CFT we calculate the average values for momentum and the angular momenta of these configurations. Finally we compare the CFT results with those obtained in the bulk from the asymptotically M 1,4 × S 1 × T 4 region.

  5. Photodetachment of O^- Yielding O(1D_2, {}^3P) Atoms, Viewed with Velocity Map Imaging

    NASA Astrophysics Data System (ADS)

    Gibson, Stephen T.; Laws, Benjamin A.; Lewis, Brenton R.; Duong, Ly

    2016-06-01

    lectron photodetachment of O^-(2P3/2,1/2) is measured using velocity-map imaging at wavelengths near 350 nm, where detachment yields both O(^1D_2) and O(^3P2,1,0) atoms, simultaneously, producing slow (˜ 0.1 eV) and fast electrons (˜ 2 eV). The photoelectron spectrum resolves the fine-structure transitions, which together with the well known atomic fine-structure splittings, and intensity ratios, provide an excellent test of the spectral quality of the velocity-map imaging technique. Although the photoelectron angular distribution for the two atomic limits have the same negative anisotropy sign, the energy dependence differs. The variation is qualitatively in accordance with R-matrix cross section calculations, that indicate a more gradual d-wave onset for the ^1D limit. However, more exact evaluation is only possible with information about the matrix element phases. Research supported by the Australian Research Council Discovery Project GrantDP160102585. physics.nist.gov/cgi-bin/ASD/energy1.pl O. Scharf and M. R. Godefried, arXiv:0808.3529v1 O. Zatsarinny and K. Bartschat, Phys. Rev. A, 73, 022714 (2006). doi:10.1103/PhysRevA.73.022714

  6. Diffusive Public Goods and Coexistence of Cooperators and Cheaters on a 1D Lattice

    PubMed Central

    Scheuring, István

    2014-01-01

    Many populations of cells cooperate through the production of extracellular materials. These materials (enzymes, siderophores) spread by diffusion and can be applied by both the cooperator and cheater (non-producer) cells. In this paper the problem of coexistence of cooperator and cheater cells is studied on a 1D lattice where cooperator cells produce a diffusive material which is beneficial to the individuals according to the local concentration of this public good. The reproduction success of a cell increases linearly with the benefit in the first model version and increases non-linearly (saturates) in the second version. Two types of update rules are considered; either the cooperative cell stops producing material before death (death-production-birth, DpB) or it produces the common material before it is selected to die (production-death-birth, pDB). The empty space is occupied by its neighbors according to their replication rates. By using analytical and numerical methods I have shown that coexistence of the cooperator and cheater cells is possible although atypical in the linear version of this 1D model if either DpB or pDB update rule is assumed. While coexistence is impossible in the non-linear model with pDB update rule, it is one of the typical behaviors in case of the non-linear model with DpB update rule. PMID:25025985

  7. Calibration of Axisymmetric and Quasi-1D Solvers for High Enthalpy Nozzles

    NASA Technical Reports Server (NTRS)

    Papadopoulos, P. E.; Gochberg, L. A.; Tokarcik-Polsky, S.; Venkatapathy, E.; Deiwert, G. S.; Edwards, Thomas A. (Technical Monitor)

    1994-01-01

    The proposed paper will present a numerical investigation of the flow characteristics and boundary layer development in the nozzles of high enthalpy shock tunnel facilities used for hypersonic propulsion testing. The computed flow will be validated against existing experimental data. Pitot pressure data obtained at the entrance of the test cabin will be used to validate the numerical simulations. It is necessary to accurately model the facility nozzles in order to characterize the test article flow conditions. Initially the axisymmetric nozzle flow will be computed using a Navier Stokes solver for a range of reservoir conditions. The calculated solutions will be compared and calibrated against available experimental data from the DLR HEG piston-driven shock tunnel and the 16-inch shock tunnel at NASA Ames Research Center. The Reynolds number is assumed to be high enough at the throat that the boundary layer flow is assumed turbulent at this point downstream. The real gas affects will be examined. In high Mach number facilities the boundary layer is thick. Attempts will be made to correlate the boundary layer displacement thickness. The displacement thickness correlation will be used to calibrate the quasi-1D codes NENZF and LSENS in order to provide fast and efficient tools of characterizing the facility nozzles. The calibrated quasi-1D codes will be implemented to study the effects of chemistry and the flow condition variations at the test section due to small variations in the driver gas conditions.

  8. Assessment of improved root growth representation in a 1-D, field scale crop model

    NASA Astrophysics Data System (ADS)

    Miltin Mboh, Cho; Gaiser, Thomas; Ewert, Frank

    2015-04-01

    Many 1-D, field scale crop models over-simplify root growth. The over-simplification of this "hidden half" of the crop may have significant consequences on simulated root water and nutrient uptake with a corresponding reflection on the simulated crop yields. Poor representation of root growth in crop models may therefore constitute a major source of uncertainty propagation. In this study we assess the effect of an improved representation of root growth in a model solution of the model framework SIMPLACE (Scientific Impact assessment and Modeling PLatform for Advanced Crop and Ecosystem management) compared to conventional 1-D approaches. The LINTUL5 crop growth model is coupled to the Hillflow soil water balance model within the SIMPLACE modeling framework (Gaiser et al, 2013). Root water uptake scenarios in the soil hydrological simulator Hillflow (Bronstert, 1995) together with an improved representation of root growth is compared to scenarios for which root growth is simplified. The improvement of root growth is achieved by integrating root growth solutions from R-SWMS (Javaux et al., 2008) into the SIMPLACE model solution. R-SWMS is a three dimensional model for simultaneous modeling of root growth, soil water fluxes and solute transport and uptake. These scenarios are tested by comparing how well the simulated water contents match with the observed soil water dynamics. The impacts of the scenarios on above ground biomass and wheat grain are assessed

  9. Testing a 1-D Analytical Salt Intrusion Model and the Predictive Equation in Malaysian Estuaries

    NASA Astrophysics Data System (ADS)

    Gisen, Jacqueline Isabella; Savenije, Hubert H. G.

    2013-04-01

    Little is known about the salt intrusion behaviour in Malaysian estuaries. Study on this topic sometimes requires large amounts of data especially if a 2-D or 3-D numerical models are used for analysis. In poor data environments, 1-D analytical models are more appropriate. For this reason, a fully analytical 1-D salt intrusion model, based on the theory of Savenije in 2005, was tested in three Malaysian estuaries (Bernam, Selangor and Muar) because it is simple and requires minimal data. In order to achieve that, site surveys were conducted in these estuaries during the dry season (June-August) at spring tide by moving boat technique. Data of cross-sections, water levels and salinity were collected, and then analysed with the salt intrusion model. This paper demonstrates a good fit between the simulated and observed salinity distribution for all three estuaries. Additionally, the calibrated Van der Burgh's coefficient K, Dispersion coefficient D0, and salt intrusion length L, for the estuaries also displayed a reasonable correlations with those calculated from the predictive equations. This indicates that not only is the salt intrusion model valid for the case studies in Malaysia but also the predictive model. Furthermore, the results from this study describe the current state of the estuaries with which the Malaysian water authority in Malaysia can make decisions on limiting water abstraction or dredging. Keywords: salt intrusion, Malaysian estuaries, discharge, predictive model, dispersion

  10. Dimensional phase transition from 1D behavior to a 3D Bose-Einstein condensate

    NASA Astrophysics Data System (ADS)

    Pelster, Axel; Morath, Denis; Straßel, Dominik; Eggert, Sebastian

    The emergence of new properties from low-dimensional building blocks is a universal theme in different areas in physics. The investigation of transitions between isolated and coupled low-dimensional systems promises to reveal new phenomena and exotic phases. Interacting 1D bosons, which are coupled in a two-dimensional array, are maybe the most fundamental example of a system which illustrates the concept of a dimensional phase transition. However, recent experiments using ultracold gases have shown a surprising discrepancy between theory and experiment and it is far from obvious if the power laws from the underlying 1D theory can predict the transition temperature and order parameter correctly for all interaction strengths. Using a combination of large-scale Quantum Monte-Carlo simulations and chain mean-field calculations, we show that the behavior of the ordering temperature as a function of inter-chain coupling strength does not follow a universal powerlaw, but also depends strongly on the filling

  11. Diffusive public goods and coexistence of cooperators and cheaters on a 1D lattice.

    PubMed

    Scheuring, István

    2014-01-01

    Many populations of cells cooperate through the production of extracellular materials. These materials (enzymes, siderophores) spread by diffusion and can be applied by both the cooperator and cheater (non-producer) cells. In this paper the problem of coexistence of cooperator and cheater cells is studied on a 1D lattice where cooperator cells produce a diffusive material which is beneficial to the individuals according to the local concentration of this public good. The reproduction success of a cell increases linearly with the benefit in the first model version and increases non-linearly (saturates) in the second version. Two types of update rules are considered; either the cooperative cell stops producing material before death (death-production-birth, DpB) or it produces the common material before it is selected to die (production-death-birth, pDB). The empty space is occupied by its neighbors according to their replication rates. By using analytical and numerical methods I have shown that coexistence of the cooperator and cheater cells is possible although atypical in the linear version of this 1D model if either DpB or pDB update rule is assumed. While coexistence is impossible in the non-linear model with pDB update rule, it is one of the typical behaviors in case of the non-linear model with DpB update rule.

  12. DISCOLORATION OF THE WETTED SURFACE IN THE 6.1D DISSOLVER

    SciTech Connect

    Rudisill, T.; Mickalonis, J.; Crapse, K.

    2013-12-18

    During a camera inspection of a failed coil in the 6.1D dissolver, an orange discoloration was observed on a portion of the dissolver wall and coils. At the request of H-Canyon Engineering, the inspection video of the dissolver was reviewed by SRNL to assess if the observed condition (a non-uniform, orange-colored substance on internal surfaces) was a result of corrosion. Although the dissolver vessel and coil corrode during dissolution operations, the high acid conditions are not consistent with the formation of ferrous oxides (i.e., orange/rust-colored corrosion products). In a subsequent investigation, SRNL performed dissolution experiments to determine if residues from the nylon bags used for Pu containment could have generated the orange discoloration following dissolution. When small pieces of a nylon bag were placed in boiling 8 M nitric acid solutions containing other components representative of the H-Canyon process, complete dissolution occurred almost immediately. No residues were obtained even when a nylon mass to volume ratio greater than 100 times the 6.1D dissolver value was used. Degradation products from the dissolution of nylon bags are not responsible for the discoloration observed in the dissolver.

  13. CoPc 2D and 1D Arrangement on a Ferromagnetic Surface.

    PubMed

    Annese, Emilia; ViolBarbosa, Carlos E; Rossi, Giorgio; Fujii, Jun

    2016-05-31

    We investigated the growth and electronic properties of Co-phthalocyanine (CoPc) molecule deposited on iron film with different structures (pseudomorph-fcc and bcc) and on iron nanowires by scanning tunnelling microscopy and X-ray absorption spectroscopy (XAS). CoPc molecules self-assemble in a two-dimensional (2D) arrangement with the molecular plane parallel to the iron surfaces, and the local order is lost after the first layer. The molecule-ferromagnet interaction causes the broadening of Co and N unoccupied molecular states as well as different electronic distribution of N states as a function of the atomic structure of iron surface. The ferromagnetic coupling between the molecule and the iron film is dominated by the electronic interaction between Co and the first Fe layer. CoPc 2D arrangement turns into 1D by using as a template the iron nanowire grown on a facet surface of oxidized Cu(332) surface. CoPc molecules interact weakly with the iron nanowires manifesting a substantial Co 3dz spectral feature in XAS spectrum and the possibility of a magnetic interaction between Co moment and iron nanowires. Both CoPc 2D and 1D arrangements can open up new interesting scenarios to tune the magnetic properties of hybrid interfaces involving metallorganic molecules. PMID:27191039

  14. Rhythm-Induced Spike-Timing Patterns Characterized by 1D Firing Map

    NASA Astrophysics Data System (ADS)

    Engelbrecht, Jan; Mirollo, Rennie

    2012-02-01

    A basic problem in neuroscience is to understand how the dynamic mechanisms that govern the responses of nerve cells to stimuli, which are both non-linear and noisy, still produce reliable collective activity. We study patterning in the responses of neurons subjected to periodic rhythms. These patterns are governed by simple, low-dimensional mathematical structures independent of modeling detail. We show both theoretically and in whole-cell recordings that the 1D map generated from successive spike times is such a construct. As expected, the stable periodic points of this 1D map cause a neuron's entrainment or phase-locking to a periodic rhythm. But our work has also revealed a complementary and unexpected patterning in the spike-timing of un-entrained neurons in the form of repeated sequences of reliable spike-phase advances, which cannot be characterized simply as a noisy perturbation near the stable periodic points of the noise-free return map. This new patterning appears to require both noise and a sufficiently steep return map.

  15. Atomic layer deposition on phase-shift lithography generated photoresist patterns for 1D nanochannel fabrication.

    PubMed

    Güder, Firat; Yang, Yang; Krüger, Michael; Stevens, Gregory B; Zacharias, Margit

    2010-12-01

    A versatile, low-cost, and flexible approach is presented for the fabrication of millimeter-long, sub-100 nm wide 1D nanochannels with tunable wall properties (wall thickness and material) over wafer-scale areas on glass, alumina, and silicon surfaces. This approach includes three fabrication steps. First, sub-100 nm photoresist line patterns were generated by near-field contact phase-shift lithography (NFC-PSL) using an inexpensive homemade borosilicate mask (NFC-PSM). Second, various metal oxides were directly coated on the resist patterns with low-temperature atomic layer deposition (ALD). Finally, the remaining photoresist was removed via an acetone dip, and then planar nanochannel arrays were formed on the substrate. In contrast to all the previous fabrication routes, the sub-100 nm photoresist line patterns produced by NFC-PSL are directly employed as a sacrificial layer for the creation of nanochannels. Because both the NFC-PSL and the ALD deposition are highly reproducible processes, the strategy proposed here can be regarded as a general route for nanochannel fabrication in a simplified and reliable manner. In addition, the fabricated nanochannels were used as templates to synthesize various organic and inorganic 1D nanostructures on the substrate surface. PMID:21047101

  16. Atomic layer deposition on phase-shift lithography generated photoresist patterns for 1D nanochannel fabrication.

    PubMed

    Güder, Firat; Yang, Yang; Krüger, Michael; Stevens, Gregory B; Zacharias, Margit

    2010-12-01

    A versatile, low-cost, and flexible approach is presented for the fabrication of millimeter-long, sub-100 nm wide 1D nanochannels with tunable wall properties (wall thickness and material) over wafer-scale areas on glass, alumina, and silicon surfaces. This approach includes three fabrication steps. First, sub-100 nm photoresist line patterns were generated by near-field contact phase-shift lithography (NFC-PSL) using an inexpensive homemade borosilicate mask (NFC-PSM). Second, various metal oxides were directly coated on the resist patterns with low-temperature atomic layer deposition (ALD). Finally, the remaining photoresist was removed via an acetone dip, and then planar nanochannel arrays were formed on the substrate. In contrast to all the previous fabrication routes, the sub-100 nm photoresist line patterns produced by NFC-PSL are directly employed as a sacrificial layer for the creation of nanochannels. Because both the NFC-PSL and the ALD deposition are highly reproducible processes, the strategy proposed here can be regarded as a general route for nanochannel fabrication in a simplified and reliable manner. In addition, the fabricated nanochannels were used as templates to synthesize various organic and inorganic 1D nanostructures on the substrate surface.

  17. NOKIN1D: one-dimensional neutron kinetics based on a nodal collocation method

    NASA Astrophysics Data System (ADS)

    Verdú, G.; Ginestar, D.; Miró, R.; Jambrina, A.; Barrachina, T.; Soler, Amparo; Concejal, Alberto

    2014-06-01

    The TRAC-BF1 one-dimensional kinetic model is a formulation of the neutron diffusion equation in the two energy groups' approximation, based on the analytical nodal method (ANM). The advantage compared with a zero-dimensional kinetic model is that the axial power profile may vary with time due to thermal-hydraulic parameter changes and/or actions of the control systems but at has the disadvantages that in unusual situations it fails to converge. The nodal collocation method developed for the neutron diffusion equation and applied to the kinetics resolution of TRAC-BF1 thermal-hydraulics, is an adaptation of the traditional collocation methods for the discretization of partial differential equations, based on the development of the solution as a linear combination of analytical functions. It has chosen to use a nodal collocation method based on a development of Legendre polynomials of neutron fluxes in each cell. The qualification is carried out by the analysis of the turbine trip transient from the NEA benchmark in Peach Bottom NPP using both the original 1D kinetics implemented in TRAC-BF1 and the 1D nodal collocation method.

  18. Nonparametric 1-D temperature restoration in lossy media using Tikhonov regularization on sparse radiometry data.

    PubMed

    Jacobsen, Svein; Stauffer, Paul R

    2003-02-01

    Microwave thermometry has the potential to characterize thermal gradients in lossy materials down to a few centimeters depth. The problem of retrieving temperature profiles from sets of brightness temperatures is studied using Galerkin expansion of one-dimensional (1-D) temperature profiles combined with Tikhonov regularization and predefined boundary conditions. From a priori knowledge of the temperature field shape, smooth Chebyshev polynomials are used as basis functions in the series expansion. The proposed estimator does not require iterative calculations that are normally performed using conventional numerical methods for signal parameter estimation and is, thus, very fast. Noise effects versus bandwidth limitations (smoothness of solutions) are studied in terms of four performance indexes defined in the text. In general, statistical spread of the temperature estimator increases with increasing number of Chebyshev polynomials. Systematic deviation from true values (bias) decreases as the number of Chebyshev polynomials increases. Results show that smooth temperature profiles can be reproduced using 6-7 Chebyshev polynomials. With additional constraints such as boundary conditions and maxima localization, a three-frequency-band radiometric scan is sufficient to produce acceptable results in regions with low thermal gradients. As the spatial variability of the 1-D temperature profile increases, more radiometric bands (5-6) are required to provide nonbiased estimates.

  19. Transient 1D transport equation simulated by a mixed Green element formulation

    NASA Astrophysics Data System (ADS)

    Taigbenu, Akpofure Efemena; Onyejekwe, Okey Oseloka

    1997-08-01

    New discrete element equations or coefficients are derived for the transient 1D diffusion-advection or transport equation based on the Green element replication of the differential equation using linear elements. The Green element method (GEM), which solves the singular boundary integral theory (a Fredholm integral equation of the second kind) on a typical element, gives rise to a banded global coefficient matrix which is amenable to efficient matrix solvers. It is herein derived for the transient 1D transport equation with uniform and non-uniform ambient flow conditions and in which first-order decay of the containment is allowed to take place. Because the GEM implements the singular boundary integral theory within each element at a time, the integrations are carried out in exact fashion, thereby making the application of the boundary integral theory more utilitarian. This system of discrete equations, presented herein for the first time, using linear interpolating functions in the spatial dimensions shows promising stable characteristics for advection-dominant transport. Three numerical examples are used to demonstrate the capabilities of the method. The second-order-correct Crank-Nicolson scheme and the modified fully implicit scheme with a difference weighting value of two give superior solutions in all simulated examples.

  20. Thermodynamics of large N gauge theories with chemical potentials in a 1/ D expansion

    NASA Astrophysics Data System (ADS)

    Morita, Takeshi

    2010-08-01

    In order to understand thermodynamical properties of N D-branes with chemical potentials associated with R-symmetry charges, we study a one dimensional large N gauge theory (bosonic BFSS type model) as a first step. This model is obtained through a dimensional reduction of a 1 + D dimensional SU( N) Yang-Mills theory and we use a 1 /D expansion to investigate the phase structure. We find three phases in the μ - T plane. We also show that all the adjoint scalars condense at large D and obtain a mass dynamically. This dynamical mass protects our model from the usual perturbative instability of massless scalars in a non-zero chemical potential. We find that the system is at least meta-stable for arbitrary large values of the chemical potentials in D → ∞ limit. We also explore the existence of similar condensation in higher dimensional gauge theories in a high temperature limit. In 2 and 3 dimensions, the condensation always happens as in one dimensional case. On the other hand, if the dimension is higher than 4, there is a critical chemical potential and the condensation happens only if the chemical potentials are below it.

  1. A world-line framework for 1D topological conformal σ-models

    NASA Astrophysics Data System (ADS)

    Baulieu, L.; Holanda, N. L.; Toppan, F.

    2015-11-01

    We use world-line methods for pseudo-supersymmetry to construct sl(2|1)-invariant actions for the (2, 2, 0) chiral and (1, 2, 1) real supermultiplets of the twisted D-module representations of the sl(2|1) superalgebra. The derived one-dimensional topological conformal σ-models are invariant under nilpotent operators. The actions are constructed for both parabolic and hyperbolic/trigonometric realizations (with extra potential terms in the latter case). The scaling dimension λ of the supermultiplets defines a coupling constant, 2λ + 1, the free theories being recovered at λ = - /1 2 . We also present, generalizing previous works, the D-module representations of one-dimensional superconformal algebras induced by N = ( p , q ) pseudo-supersymmetry acting on (k, n, n - k) supermultiplets. Besides sl(2|1), we obtain the superalgebras A(1, 1), D(2, 1; α), D(3, 1), D(4, 1), A(2, 1) from (p, q) = (1, 1), (2, 2), (3, 3), (4, 4), (5, 1), at given k, n and critical values of λ.

  2. 1D and 2D Assembly of Plant Viruses for Materials Development

    SciTech Connect

    Qian Wang

    2013-01-11

    The research focused on the development of novel bionanoparticle (BNP)-based materials, especially the assembly of chemically and genetically-tailored BNP at the interface between immiscible fluids. The chemical, physical, dynamical and mechanistic aspects have been studied in this research. In particular, rod-like tobacco mosaic virus (TMV) based anisotropic nanorods were synthesized via RNA or polymer assisted assembling process. Such kind of TMV-rods offers an ideal model system for the mechanistic study of orienting and packing anisotropic nanoparticles, which may have great potential in the applications of photovoltaic and field emission devices. Specific objectives include: 1) Synthesize BNPs with controlled functionality at defined positions; 2) synthesize 1D nanorods with defined length via polymer or RNA assisted assembly of TMV or TMV coat proteins; 3) self-assemble and crosslink BNPs and TMV-nanorods at liquid-liquid interfaces; 4) quantitatively characterize the structural organization of the 1D and 2D BNP-assemblies using both small angle neutron scattering and synchrotron small angle X-ray scattering; and 5) develop methods to apply grazing incidence small angle X-ray/neutron scattering to investigate the assemblies of BNPs.

  3. Quasi-1D physics in metal-organic frameworks: MIL-47(V) from first principles

    PubMed Central

    Jaeken, Jan W; De Baerdemacker, Stijn; Lejaeghere, Kurt; Van Speybroeck, Veronique

    2014-01-01

    Summary The geometric and electronic structure of the MIL-47(V) metal-organic framework (MOF) is investigated by using ab initio density functional theory (DFT) calculations. Special focus is placed on the relation between the spin configuration and the properties of the MOF. The ground state is found to be antiferromagnetic, with an equilibrium volume of 1554.70 Å3. The transition pressure of the pressure-induced large-pore-to-narrow-pore phase transition is calculated to be 82 MPa and 124 MPa for systems with ferromagnetic and antiferromagnetic chains, respectively. For a mixed system, the transition pressure is found to be a weighted average of the ferromagnetic and antiferromagnetic transition pressures. Mapping DFT energies onto a simple-spin Hamiltonian shows both the intra- and inter-chain coupling to be antiferromagnetic, with the latter coupling constant being two orders of magnitude smaller than the former, suggesting the MIL-47(V) to present quasi-1D behavior. The electronic structure of the different spin configurations is investigated and it shows that the band gap position varies strongly with the spin configuration. The valence and conduction bands show a clear V d-character. In addition, these bands are flat in directions orthogonal to VO6 chains, while showing dispersion along the the direction of the VO6 chains, similar as for other quasi-1D materials. PMID:25383285

  4. Optimisation of A 1d-ecosystem Model To Observations In The North Atlantic Ocean

    NASA Astrophysics Data System (ADS)

    Schartau, M.; Oschlies, A.

    An optimisation experiment is performed with a vertically resolved, nitrogen based ecosystem model, comprising four state variables (1D-NPZD model): dissolved inor- ganic nitrogen (N), phytoplankton (P), herbivorous zooplankton (Z) and detritus (D). Parameter values of the NPZD-model are optimised while regarding observational data from three locations in the North Atlantic simultaneously: Bermuda Atlantic Time-series Study (BATS), data of the North Atlantic Bloom Experiment (NABE) and observations from Ocean Weather Ship-India (OWS-INDIA). The simultaneous opti- misation yields a best parameter set which can be utilized for basin wide simulations in coupled physical-biological (general circulation) models of the North Atlantic. After optimisation of the 1D-NPZD model, systematic discrepancies between 14C-fixation rates and modelled primary production are emphasized. Using the optimal parame- ter estimates for coupled 3D-simulations, the biogeochemical fluxes show substantial differences in contrast to previous model results. For instance, rapid recycling of or- ganic matter enhances primary production rates. This becomes most evident within the oligotrophic regions of the subtropical gyre.

  5. Quasinormal modes of (anti-)de Sitter black holes in the 1 /D expansion

    NASA Astrophysics Data System (ADS)

    Emparan, Roberto; Suzuki, Ryotaku; Tanabe, Kentaro

    2015-04-01

    We use the inverse-dimensional expansion to compute analytically the frequencies of a set of quasinormal modes of static black holes of Einstein-(Anti-)de Sitter gravity, including the cases of spherical, planar or hyperbolic horizons. The modes we study are decoupled modes localized in the near-horizon region, which are the ones that capture physics peculiar to each black hole (such as their instabilities), and which in large black holes contain hydrodynamic behavior. Our results also give the unstable Gregory-Laflamme frequencies of Ricci-flat black branes to two orders higher in 1 /D than previous calculations. We discuss the limits on the accuracy of these results due to the asymptotic but not convergent character of the 1 /D expansion, which is due to the violation of the decoupling condition at finite D. Finally, we compare the frequencies for AdS black branes to calculations in the hydrodynamic expansion in powers of the momentum k. Our results extend up to k 9 for the sound mode and to k 8 for the shear mode.

  6. What is the smallest physically acceptable scale for 1D turbulence schemes ?

    NASA Astrophysics Data System (ADS)

    Honnert, Rachel; Masson, Valéry

    2014-10-01

    In numerical weather prediction (NWP) models, at mesoscale, the subgrid convective boundary-layer turbulence is dominated by the uni-directional (1D) vertical thermal production. In Large-Eddy Simulations (LES), the thermal plumes are resolved and the residual subgrid turbulent motions are homogeneous and isotropic, thus three-dimensional (3D), resulting from the dynamical production. This article sets the critical horizontal resolution for which the usually 1D turbulence schemes of NWP models must be replaced by 3D turbulence schemes. LES from five dry and cumulus-topped free convective boundary layers and one forced convective boundary layer are performed. From these LES data, the thermal production and vertical and horizontal dynamical productions are calculated at several resolutions from LES to mesoscale. It appears that the production terms of both dry and cumulus-topped free convective boundary layers have the same behavior. A pattern emerges whenever data are ranked by the resolution scaled by the size of thermal plumes, (h + hc , where h is the boundary-layer height and hc is the depth of the cloud layer). In free onvective boundary layers, the critical horizontal resolution for which the horizontal motions must be represented is 0.5(h + hc ). However, the critical horizontal resolution in the forced convective boundary layer case is 3(h + hc ).

  7. Measurements of O(1 D) quenching rates in the F-region

    NASA Technical Reports Server (NTRS)

    Sipler, D. P.; Biondi, M. A.

    1972-01-01

    In-situ determinations of the quenching of O(1 D) atoms by N2 and O2 molecules were made from observations of 6300 A nightglow intensity enhancements produced by the Platteville 1.6 MW transmitter. The heating of F-region electrons near the point of reflection of the RF wave leads to electron impact excitation of oxygen atoms to the O(1 D) state. It is shown that the resulting region of enhance 6300 A emission is localized to the region of electron energy absorption for heating at the lower altitudes. At 225 km the measured time constants for intensity buildup following transmitter turn-on and for intensity decay following turn-off are identical and equal to (13 plus or minus 1) sec. Time constants varying from 30 to 80 sec are found for the altitude range 260 to 300 km. The inferred quenching coefficient for the whole altitude range, 225 to 300 km, is 4.4 + 2 or - 1 x 10 to the minus 11th power cu cm/sec at 950 K, in good agreement with laboratory data. The quenching frequency obtained at 225 km, when referred to the altitude 120 km, is equal to (21 plus or minus 2)/sec, in agreement with less direct ionospheric determinations.

  8. Tunable Splitting of the Ground-State Degeneracy in 1D Parafermionic Wires

    NASA Astrophysics Data System (ADS)

    Chen, Chun; Burnell, Fiona

    Systems with topologically protected ground-state degeneracies are currently of great interest due to their potential applications in quantum computing. In practise this degeneracy is never exact, and the magnitude of the ground-state degeneracy splitting imposes constraints on the timescales over which information is topologically protected. In this Letter we use an instanton approach to evaluate the splitting of topological ground-state degeneracy in quasi-1D systems with parafermion zero modes, in the specific case where parafermions are realized by inducing a superconducting gap in pairs of fractional quantum Hall (FQH) edges. We show that, like 1D topological superconducting wires, this splitting has an oscillatory dependence on the chemical potential, which arises from an intrinsic Berry phase that produces interference between distinct instanton tunneling events. These Berry phases can be mapped to chiral phases in a (dual) quantum clock model using a Fradkin-Kadanoff transformation. Comparing our low-energy spectrum to that of phenomenological parafermion models allows us to evaluate the real and imaginary parts of the hopping integral between adjacent parafermionic zero modes as functions of the chemical potential.

  9. CD1d Expression and Invariant NKT Cell Responses in Herpesvirus Infections

    PubMed Central

    Chung, Brian K.; Priatel, John J.; Tan, Rusung

    2015-01-01

    Invariant natural killer T (iNKT) cells are a highly conserved subset of unconventional T lymphocytes that express a canonical, semi-invariant T cell receptor and surface markers shared with the natural killer cell lineage. iNKT cells recognize exogenous and endogenous glycolipid antigens restricted by non-polymorphic CD1d molecules, and are highly responsive to the prototypical agonist, α-galactosylceramide. Upon activation, iNKT cells rapidly coordinate signaling between innate and adaptive immune cells through the secretion of proinflammatory cytokines, leading to the maturation of antigen-presenting cells, and expansion of antigen-specific CD4+ and CD8+ T cells. Because of their potent immunoregulatory properties, iNKT cells have been extensively studied and are known to play a pivotal role in mediating immune responses against microbial pathogens including viruses. Here, we review evidence that herpesviruses manipulate CD1d expression to escape iNKT cell surveillance and establish lifelong latency in humans. Collectively, published findings suggest that iNKT cells play critical roles in anti-herpesvirus immune responses and could be harnessed therapeutically to limit viral infection and viral-associated disease. PMID:26161082

  10. A facile route for 3D aerogels from nanostructured 1D and 2D materials.

    PubMed

    Jung, Sung Mi; Jung, Hyun Young; Dresselhaus, Mildred S; Jung, Yung Joon; Kong, Jing

    2012-01-01

    Aerogels have numerous applications due to their high surface area and low densities. However, creating aerogels from a large variety of materials has remained an outstanding challenge. Here, we report a new methodology to enable aerogel production with a wide range of materials. The method is based on the assembly of anisotropic nano-objects (one-dimensional (1D) nanotubes, nanowires, or two-dimensional (2D) nanosheets) into a cross-linking network from their colloidal suspensions at the transition from the semi-dilute to the isotropic concentrated regime. The resultant aerogels have highly porous and ultrafine three-dimensional (3D) networks consisting of 1D (Ag, Si, MnO(2), single-walled carbon nanotubes (SWNTs)) and 2D materials (MoS(2), graphene, h-BN) with high surface areas, low densities, and high electrical conductivities. This method opens up a facile route for aerogel production with a wide variety of materials and tremendous opportunities for bio-scaffold, energy storage, thermoelectric, catalysis, and hydrogen storage applications.

  11. 1D self-assembly of chemisorbed thymine on Cu(110) driven by dispersion forces

    NASA Astrophysics Data System (ADS)

    Temprano, I.; Thomas, G.; Haq, S.; Dyer, M. S.; Latter, E. G.; Darling, G. R.; Uvdal, P.; Raval, R.

    2015-03-01

    Adsorption of thymine on a defined Cu(110) surface was studied using reflection-absorption infrared spectroscopy (RAIRS), temperature programmed desorption (TPD), and scanning tunnelling microscopy (STM). In addition, density functional theory (DFT) calculations were undertaken in order to further understand the energetics of adsorption and self-assembly. The combination of RAIRS, TPD, and DFT results indicates that an upright, three-point-bonded adsorption configuration is adopted by the deprotonated thymine at room temperature. DFT calculations show that the upright configuration adopted by individual molecules arises as a direct result of strong O-Cu and N-Cu bonds between the molecule and the surface. STM data reveal that this upright thymine motif self-assembles into 1D chains, which are surprisingly oriented along the open-packed [001] direction of the metal surface and orthogonal to the alignment of the functional groups that are normally implicated in H-bonding interactions. DFT modelling of this system reveals that the molecular organisation is actually driven by dispersion interactions, which cause a slight tilt of the molecule and provide the major driving force for assembly into dimers and 1D chains. The relative orientations and distances of neighbouring molecules are amenable for π-π stacking, suggesting that this is an important contributor in the self-assembly process.

  12. Reduced synaptic vesicle protein degradation at lysosomes curbs TBC1D24/sky-induced neurodegeneration

    PubMed Central

    Fernandes, Ana Clara; Uytterhoeven, Valerie; Kuenen, Sabine; Wang, Yu-Chun; Slabbaert, Jan R.; Swerts, Jef; Kasprowicz, Jaroslaw; Aerts, Stein

    2014-01-01

    Synaptic demise and accumulation of dysfunctional proteins are thought of as common features in neurodegeneration. However, the mechanisms by which synaptic proteins turn over remain elusive. In this paper, we study Drosophila melanogaster lacking active TBC1D24/Skywalker (Sky), a protein that in humans causes severe neurodegeneration, epilepsy, and DOOR (deafness, onychdystrophy, osteodystrophy, and mental retardation) syndrome, and identify endosome-to-lysosome trafficking as a mechanism for degradation of synaptic vesicle-associated proteins. In fly sky mutants, synaptic vesicles traveled excessively to endosomes. Using chimeric fluorescent timers, we show that synaptic vesicle-associated proteins were younger on average, suggesting that older proteins are more efficiently degraded. Using a genetic screen, we find that reducing endosomal-to-lysosomal trafficking, controlled by the homotypic fusion and vacuole protein sorting (HOPS) complex, rescued the neurotransmission and neurodegeneration defects in sky mutants. Consistently, synaptic vesicle proteins were older in HOPS complex mutants, and these mutants also showed reduced neurotransmission. Our findings define a mechanism in which synaptic transmission is facilitated by efficient protein turnover at lysosomes and identify a potential strategy to suppress defects arising from TBC1D24 mutations in humans. PMID:25422373

  13. Laser-induced crystallization and crystal growth.

    PubMed

    Sugiyama, Teruki; Masuhara, Hiroshi

    2011-11-01

    Recent streams of laser studies on crystallization and crystal growth are summarized and reviewed. Femtosecond multiphoton excitation of solutions leads to their ablation at the focal point, inducing local bubble formation, shockwave propagation, and convection flow. This phenomenon, called "laser micro tsunami" makes it possible to trigger crystallization of molecules and proteins from their supersaturated solutions. Femtosecond laser ablation of a urea crystal in solution triggers the additional growth of a single daughter crystal. Intense continuous wave (CW) near infrared laser irradiation at the air/solution interface of heavy-water amino acid solutions results in trapping of the clusters and evolves to crystallization. A single crystal is always prepared in a spatially and temporally controlled manner, and the crystal polymorph of glycine depends on laser power, polarization, and solution concentration. Upon irradiation at the glass/solution interface, a millimeter-sized droplet is formed, and a single crystal is formed by shifting the irradiation position to the surface. Directional and selective crystal growth is also possible with laser trapping. Finally, characteristics of laser-induced crystallization and crystal growth are summarized.

  14. Using Inorganic Crystals To Grow Protein Crystals

    NASA Technical Reports Server (NTRS)

    Shlichta, Paul J.; Mcpherson, Alexander A.

    1989-01-01

    Solid materials serve as nucleating agents. Protein crystals induced by heterogeneous nucleation and in some cases by epitaxy to grow at lower supersaturations than needed for spontaneous nucleation. Heterogeneous nucleation makes possible to grow large, defect-free single crystals of protein more readily. Such protein crystals benefits research in biochemistry and pharmacology.

  15. Adipocyte-specific CD1d-deficiency mitigates diet-induced obesity and insulin resistance in mice

    PubMed Central

    Satoh, Masashi; Hoshino, Miyuki; Fujita, Koki; Iizuka, Misao; Fujii, Satoshi; Clingan, Christopher S.; Van Kaer, Luc; Iwabuchi, Kazuya

    2016-01-01

    It has been shown that CD1d expression and glycolipid-reactive, CD1d-restricted NKT cells exacerbate the development of obesity and insulin resistance in mice. However, the relevant CD1d-expressing cells that influence the effects of NKT cells on the progression of obesity remain incompletely defined. In this study, we have demonstrated that 3T3-L1 adipocytes can present endogenous ligands to NKT cells, leading to IFN-γ production, which in turn, stimulated 3T3-L1 adipocytes to enhance expression of CD1d and CCL2, and decrease expression of adiponectin. Furthermore, adipocyte-specific CD1d deletion decreased the size of the visceral adipose tissue mass and enhanced insulin sensitivity in mice fed a high-fat diet (HFD). Accordingly, NKT cells were less activated, IFN-γ production was significantly reduced, and levels of adiponectin were increased in these animals as compared with control mice on HFD. Importantly, macrophage recruitment into the adipose tissue of adipocyte-specific CD1d-deficient mice was significantly blunted. These findings indicate that interactions between NKT cells and CD1d-expressing adipocytes producing endogenous NKT cell ligands play a critical role in the induction of inflammation and functional modulation of adipose tissue that leads to obesity. PMID:27329323

  16. Syntrophin isoforms play specific functional roles in the α1D-adrenergic receptor/DAPC signalosome

    PubMed Central

    Lyssand, John S.; Lee, Kyung-Soon; DeFino, Mia; Adams, Marvin E.; Hague, Chris

    2014-01-01

    α1D-Adrenergic receptors, key regulators of cardiovascular system function, are organized as a multi-protein complex in the plasma membrane. Using a Type-I PDZ-binding motif in their distal C-terminal domain, α1D-ARs associate with syntrophins and dystrophin-associated protein complex (DAPC) members utrophin, dystrobrevin and α-catulin. Three of the five syntrophin isoforms (α, β1 and β2) interact with α1D-ARs and our previous studies suggest multiple isoforms are required for proper α1D-AR function in vivo. This study determined the contribution of each specific syntrophin isoform to α1D-AR function. Radioligand binding experiments reveal α-syntrophin enhances α1D-AR binding site density, while phosphoinositol and ERK1/2 signaling assays indicate β2-syntrophin augments full and partial agonist efficacy for coupling to downstream signaling mechanisms. The results of this study provide clear evidence that the cytosolic components within the α1D-AR/DAPC signalosome significantly alter the pharmacological properties of α1-AR ligands in vitro. PMID:21846462

  17. Lysophospholipid presentation by CD1d and recognition by a human Natural Killer T-cell receptor

    SciTech Connect

    López-Sagaseta, Jacinto; Sibener, Leah V.; Kung, Jennifer E.; Gumperz, Jenny; Adams, Erin J.

    2014-10-02

    Invariant Natural Killer T (iNKT) cells use highly restricted {alpha}{beta} T cell receptors (TCRs) to probe the repertoire of lipids presented by CD1d molecules. Here, we describe our studies of lysophosphatidylcholine (LPC) presentation by human CD1d and its recognition by a native, LPC-specific iNKT TCR. Human CD1d presenting LPC adopts an altered conformation from that of CD1d presenting glycolipid antigens, with a shifted {alpha}1 helix resulting in an open A pocket. Binding of the iNKT TCR requires a 7-{angstrom} displacement of the LPC headgroup but stabilizes the CD1d-LPC complex in a closed conformation. The iNKT TCR CDR loop footprint on CD1d-LPC is anchored by the conserved positioning of the CDR3{alpha} loop, whereas the remaining CDR loops are shifted, due in part to amino-acid differences in the CDR3{beta} and J{beta} segment used by this iNKT TCR. These findings provide insight into how lysophospholipids are presented by human CD1d molecules and how this complex is recognized by some, but not all, human iNKT cells.

  18. Evaluation of static pressure drops and PM10 and TSP emissions for modified 1D-3D cyclones

    SciTech Connect

    Holt, G.A.; Baker, R.V.; Hughs, S.E.

    1999-12-01

    Five modifications of a standard 1D3D cyclone were tested and compared against the standard 1D3D design in the areas of particulate emissions and static pressure drop across the cyclone. The modifications to the 1D3D design included a 2D2D inlet, a 2D2D air outlet, a D/3 trash exit, an expansion chamber with a D/3 trash exit, and a tapered air outlet duct. The 1D3D modifications that exhibited a significant improvement in reducing both PM10 and total suspended particulate (TSP) emissions were the designs with the 2D2D inlet and air exhaust combined with either the conical D/3 tail cone or the expansion chamber. In reference to the standard 1D3D cyclone, the average reduction in PM10 emissions was 24 to 29% with a 29 to 35% reduction observed in TSP emissions. The modifications with the tapered air outlets did not show any significant improvements in controlling PM10 emissions. However, the modification with the tapered air outlet/expansion chamber combination exhibited statistical significance in reducing TSP emissions by 18% compared to the 1D3D cyclone. All modifications tested exhibited lower static pressure drops than the standard 1D3D.

  19. Retinoic acid regulates CD1d gene expression at the transcriptional level in human and rodent monocytic cells.

    PubMed

    Chen, Qiuyan; Ross, A Catharine

    2007-04-01

    CD1d belongs to a group of nonclassical antigen-presenting molecules that present glycolipid antigens and thereby activate natural killer T (NKT) cells, a subset of bifunctional T cells. Little is known so far regarding the expression and physiologic regulation of CD1d. Here we show that all-trans-retinoic acid (RA), the active metabolite of vitamin A, rapidly (1 hr after treatment) increases CD1d mRNA in human and rodent monocytic cells at a physiologic dose (10 nM). The induction is RA specific and RA receptor (RAR) dependent-RA and an RARalpha agonist, Am580, both had a pronounced positive effect, whereas the addition of RARalpha antagonist partially blocked the increase in CD1d mRNA induced by RA and Am580. The induction was also completely blocked by the presence of actinomycin D. A putative RA-response element was identified in the distal 5' flanking region of the CD1d gene, which binds nuclear retinoid receptors and was responsive to RA in both gel mobility shift assay and transient transfection assay in THP-1 cells. These results further confirmed the transcriptional regulation of RA in CD1d gene expression. Moreover, RA significantly increased alpha-galactosylceramide-induced spleen cell proliferation. These studies together provide evidence for a previously unknown mechanism of CD1d gene expression regulation by RA and suggest that RA is a significant modulator of NKT cell activation.

  20. Role for lysosomal phospholipase A2 in iNKT cell-mediated CD1d recognition

    PubMed Central

    Paduraru, Crina; Bezbradica, Jelena S.; Kunte, Amit; Kelly, Robert; Shayman, James A.; Veerapen, Natacha; Cox, Liam R.; Besra, Gurdyal S.; Cresswell, Peter

    2013-01-01

    Invariant natural killer T (iNKT) cells recognize self lipid antigens presented by CD1d molecules. The nature of the self-antigens involved in the development and maturation of iNKT cells is poorly defined. Lysophospholipids are self-antigens presented by CD1d that are generated through the action of phospholipases A1 and A2. Lysosomal phospholipase A2 (LPLA2, group XV phospholipase A2) resides in the endocytic system, the main site where CD1d antigen acquisition occurs, suggesting that it could be particularly important in CD1d function. We find that Lpla2−/− mice show a decrease in iNKT cell numbers that is neither the result of a general effect on the development of lymphocyte populations nor of effects on CD1d expression. However, endogenous lipid antigen presentation by CD1d is reduced in the absence of LPLA2. Our data suggest that LPLA2 plays a role in the generation of CD1d complexes with thymic lipids required for the normal selection and maturation of iNKT cells. PMID:23493550

  1. Dynamics of the gas-liquid interfacial reaction of O(1D) with a liquid hydrocarbon.

    PubMed

    Waring, Carla; King, Kerry L; Costen, Matthew L; McKendrick, Kenneth G

    2011-06-30

    The dynamics of the gas-liquid interfacial reaction of the first electronically excited state of the oxygen atom, O((1)D), with the surface of a liquid hydrocarbon, squalane (C(30)H(62); 2,6,10,15,19,23-hexamethyltetracosane) has been studied experimentally. Translationally hot O((1)D) atoms were generated by 193 nm photolysis of a low pressure (nominally 1 mTorr) of N(2)O a short distance (mean = 6 mm) above a continually refreshed liquid squalane surface. Nascent OH (X(2)Π, v' = 0) reaction products were detected by laser-induced fluorescence (LIF) on the OH A(2)Σ(+)-X(2)Π (1,0) band at the same distance above the surface. The speed distribution of the recoiling OH was characterized by measuring the appearance profiles as a function of photolysis-probe delay for selected rotational levels, N'. The rotational (and, partially, fine-structure) state distributions were also measured by recording LIF excitation spectra at selected photolysis-probe delays. The OH v' = 0 rotational distribution is bimodal and can be empirically decomposed into near thermal (~300 K) and much hotter (~6000 K) Boltzmann-temperature components. There is a strong positive correlation between rotational excitation and translation energy. However, the colder rotational component still represents a significant fraction (~30%) of the fastest products, which have substantially superthermal speeds. We estimate an approximate upper limit of 3% for the quantum yield of OH per O((1)D) atom that collides with the surface. By comparison with established mechanisms for the corresponding reactions in the gas phase, we conclude that the rotationally and translationally hot products are formed via a nonstatistical insertion mechanism. The rotationally cold but translationally hot component is most likely produced by direct abstraction. Secondary collisions at the liquid surface of products of either of the previous two mechanisms are most likely responsible for the rotationally and translationally cold

  2. Higher-order local and non-local correlations for 1D strongly interacting Bose gas

    NASA Astrophysics Data System (ADS)

    Nandani, EJKP; Römer, Rudolf A.; Tan, Shina; Guan, Xi-Wen

    2016-05-01

    The correlation function is an important quantity in the physics of ultracold quantum gases because it provides information about the quantum many-body wave function beyond the simple density profile. In this paper we first study the M-body local correlation functions, g M , of the one-dimensional (1D) strongly repulsive Bose gas within the Lieb-Liniger model using the analytical method proposed by Gangardt and Shlyapnikov (2003 Phys. Rev. Lett. 90 010401; 2003 New J. Phys. 5 79). In the strong repulsion regime the 1D Bose gas at low temperatures is equivalent to a gas of ideal particles obeying the non-mutual generalized exclusion statistics with a statistical parameter α =1-2/γ , i.e. the quasimomenta of N strongly interacting bosons map to the momenta of N free fermions via {k}i≈ α {k}iF with i=1,\\ldots ,N. Here γ is the dimensionless interaction strength within the Lieb-Liniger model. We rigorously prove that such a statistical parameter α solely determines the sub-leading order contribution to the M-body local correlation function of the gas at strong but finite interaction strengths. We explicitly calculate the correlation functions g M in terms of γ and α at zero, low, and intermediate temperatures. For M = 2 and 3 our results reproduce the known expressions for g 2 and g 3 with sub-leading terms (see for instance (Vadim et al 2006 Phys. Rev. A 73 051604(R); Kormos et al 2009 Phys. Rev. Lett. 103 210404; Wang et al 2013 Phys. Rev. A 87 043634). We also express the leading order of the short distance non-local correlation functions < {{{\\Psi }}}\\dagger ({x}1)\\cdots {{{\\Psi }}}\\dagger ({x}M){{\\Psi }}({y}M)\\cdots {{\\Psi }}({y}1)> of the strongly repulsive Bose gas in terms of the wave function of M bosons at zero collision energy and zero total momentum. Here {{\\Psi }}(x) is the boson annihilation operator. These general formulas of the higher-order local and non-local correlation functions of the 1D Bose gas provide new insights into the

  3. Assessing the impact of different sources of topographic data on 1-D hydraulic modelling of floods

    NASA Astrophysics Data System (ADS)

    Ali, A. Md; Solomatine, D. P.; Di Baldassarre, G.

    2015-01-01

    Topographic data, such as digital elevation models (DEMs), are essential input in flood inundation modelling. DEMs can be derived from several sources either through remote sensing techniques (spaceborne or airborne imagery) or from traditional methods (ground survey). The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), the Shuttle Radar Topography Mission (SRTM), the light detection and ranging (lidar), and topographic contour maps are some of the most commonly used sources of data for DEMs. These DEMs are characterized by different precision and accuracy. On the one hand, the spatial resolution of low-cost DEMs from satellite imagery, such as ASTER and SRTM, is rather coarse (around 30 to 90 m). On the other hand, the lidar technique is able to produce high-resolution DEMs (at around 1 m), but at a much higher cost. Lastly, contour mapping based on ground survey is time consuming, particularly for higher scales, and may not be possible for some remote areas. The use of these different sources of DEM obviously affects the results of flood inundation models. This paper shows and compares a number of 1-D hydraulic models developed using HEC-RAS as model code and the aforementioned sources of DEM as geometric input. To test model selection, the outcomes of the 1-D models were also compared, in terms of flood water levels, to the results of 2-D models (LISFLOOD-FP). The study was carried out on a reach of the Johor River, in Malaysia. The effect of the different sources of DEMs (and different resolutions) was investigated by considering the performance of the hydraulic models in simulating flood water levels as well as inundation maps. The outcomes of our study show that the use of different DEMs has serious implications to the results of hydraulic models. The outcomes also indicate that the loss of model accuracy due to re-sampling the highest resolution DEM (i.e. lidar 1 m) to lower resolution is much less than the loss of model accuracy due

  4. Optineurin mediates a negative regulation of Rab8 by the GTPase-activating protein TBC1D17.

    PubMed

    Vaibhava, Vipul; Nagabhushana, Ananthamurthy; Chalasani, Madhavi Latha Somaraju; Sudhakar, Cherukuri; Kumari, Asha; Swarup, Ghanshyam

    2012-11-01

    Rab GTPases regulate various membrane trafficking pathways but the mechanisms by which GTPase-activating proteins recognise specific Rabs are not clear. Rab8 is involved in controlling several trafficking processes, including the trafficking of transferrin receptor from the early endosome to the recycling endosome. Here, we provide evidence to show that TBC1D17, a Rab GTPase-activating protein, through its catalytic activity, regulates Rab8-mediated endocytic trafficking of transferrin receptor. Optineurin, a Rab8-binding effector protein, mediates the interaction and colocalisation of TBC1D17 with Rab8. A non-catalytic region of TBC1D17 is required for direct interaction with optineurin. Co-expression of Rab8, but not other Rabs tested, rescues the inhibition of transferrin receptor trafficking by TBC1D17. The activated GTP-bound form of Rab8 is localised to the tubules emanating from the endocytic recycling compartment. Through its catalytic activity, TBC1D17 inhibits recruitment of Rab8 to the tubules and reduces colocalisation of transferrin receptor and Rab8. Knockdown of optineurin or TBC1D17 results in enhanced recruitment of Rab8 to the tubules. A glaucoma-associated mutant of optineurin, E50K, causes enhanced inhibition of Rab8 by TBC1D17, resulting in defective endocytic recycling of transferrin receptor. Our results show that TBC1D17, through its interaction with optineurin, regulates Rab8-mediated endocytic recycling of transferrin receptor and recruitment of Rab8 to the endocytic recycling tubules. We describe a mechanism of regulating a Rab GTPase by an effector protein (optineurin) that acts as an adaptor to bring together a Rab (Rab8) and its GTPase-activating protein (TBC1D17).

  5. Profiles of 5-HT 1B/1D agonists in acute migraine with special reference to second generation agents.

    PubMed

    Deleu, D; Hanssens, Y

    1999-06-01

    The efficacy of 5-hydroxytryptamine 1B/1D (5-HT 1B/1D) agonists is related to their inhibitory effects on neurogenic inflammation, mediated through serotoninergic control mechanisms. Recently, a series of oral second generation 5-HT 1B/1D agonists (eletriptan, naratriptan, rizatriptan and zolmitriptan) have been developed and are reviewed in this paper. Their in vitro and in vivo pharmacological properties, clinical efficacy, drug interactions, and adverse effects are evaluated and compared to the gold standard in the treatment of acute migraine, sumatriptan. PMID:10427351

  6. Wavelength modulated SERS hot spot distribution in 1D nanostructures on metal film

    NASA Astrophysics Data System (ADS)

    Wang, Lili; Zeng, Xiping; Liu, Ting; Zhang, Xuemei; Wei, Hua; Huang, Yingzhou; Liu, Anping; Wang, Shuxia; Wen, Weijia

    2016-10-01

    Surface plasmons confining strong electromagnetic fields near metal surfaces, well-known as hot spots, provide an extremely efficient platform for surface-enhanced Raman scattering (SERS). In this work, SERS spectra of probing molecules in a silver particle-wire 1D nanostructure on a thin gold film are investigated. The Raman features of SERS spectra collected at the particle-wire joints exhibit an obvious wavelength dependence phenomenon. This result is confirmed electromagnetic field simulation, revealing that hot spot distribution is sensitively influenced by the wavelength of incident light at the joints. Further studies indicate this wavelength dependence of hot spot distribution is immune to influence from the geometric shape of the particle or the angle between wire and particle, which improves fabrication tolerance. This technology may have promising applications in surface plasmon related fields, such as ultrasensors, solar energy and selective surface catalysis.

  7. Fep1d: a script for the analysis of reaction coordinates.

    PubMed

    Banushkina, Polina V; Krivov, Sergei V

    2015-05-01

    The dynamics of complex systems with many degrees of freedom can be analyzed by projecting it onto one or few coordinates (collective variables). The dynamics is often described then as diffusion on a free energy landscape associated with the coordinates. Fep1d is a script for the analysis of such one-dimensional coordinates. The script allows one to construct conventional and cut-based free energy profiles, to assess the optimality of a reaction coordinate, to inspect whether the dynamics projected on the coordinate is diffusive, to transform (rescale) the reaction coordinate to more convenient ones, and to compute such quantities as the mean first passage time, the transition path times, the coordinate dependent diffusion coefficient, and so forth. Here, we describe the implemented functionality together with the underlying theoretical framework.

  8. Fluid friction and wall viscosity of the 1D blood flow model.

    PubMed

    Wang, Xiao-Fei; Nishi, Shohei; Matsukawa, Mami; Ghigo, Arthur; Lagrée, Pierre-Yves; Fullana, Jose-Maria

    2016-02-29

    We study the behavior of the pulse waves of water into a flexible tube for application to blood flow simulations. In pulse waves both fluid friction and wall viscosity are damping factors, and difficult to evaluate separately. In this paper, the coefficients of fluid friction and wall viscosity are estimated by fitting a nonlinear 1D flow model to experimental data. In the experimental setup, a distensible tube is connected to a piston pump at one end and closed at another end. The pressure and wall displacements are measured simultaneously. A good agreement between model predictions and experiments was achieved. For amplitude decrease, the effect of wall viscosity on the pulse wave has been shown as important as that of fluid viscosity. PMID:26862041

  9. Mt Response of a 1d Earth Model Employing the Born Approximation with Variable Background Conductivities

    NASA Astrophysics Data System (ADS)

    Tejero, A.; Chavez, R. E.

    2001-12-01

    The Born approximation method has been commonly employed to study the electromagnetic field response. Other interpretative techniques have benn employed based upon the Born Approximation, like the extended Born approximation (EBA). This method employs the total field, instead of the primary field. Also, the Quasi Linear Approximation method (QLA) is an extension of EVA. In the present work, we propose an alternative technique, which employs the Born Approximation using variable background conductivities (BAVBC). The Green function is represented as a Born perturbation of zero order. Such that, the reference medium conductivity is a parameter selected according the working frequency. A similar procedure has been reported for stratified 1D-earth seismic models. This technique (BAVBC) has been applied to model computational models with reasonable results, as compared with available computational packages in the market. This method permits variations in the conductivity contrast of up to 80%, which provides solutions with 30% error, with respect of the analytical solution.

  10. Smooth non-extremal D1-D5-P solutions as charged gravitational instantons

    NASA Astrophysics Data System (ADS)

    Chakrabarty, Bidisha; Rocha, Jorge V.; Virmani, Amitabh

    2016-08-01

    We present an alternative and more direct construction of the non-super-symmetric D1-D5-P supergravity solutions found by Jejjala, Madden, Ross and Titchener. We show that these solutions — with all three charges and both rotations turned on — can be viewed as a charged version of the Myers-Perry instanton. We present an inverse scattering construction of the Myers-Perry instanton metric in Euclidean five-dimensional gravity. The angular momentum bounds in this construction turn out to be precisely the ones necessary for the smooth microstate geometries. We add charges on the Myers-Perry instanton using appropriate SO(4, 4) hidden symmetry transformations. The full construc-tion can be viewed as an extension and simplification of a previous work by Katsimpouri, Kleinschmidt and Virmani.

  11. 1D GAS-DYNAMIC SIMULATION OF SHOCK-WAVE PROCESSES VIA INTERNET

    SciTech Connect

    Khishchenko, K. V.; Levashov, P. R.; Povarnitsyn, M. E.; Zakharenkov, A. S.

    2009-12-28

    We present a Web-interface for 1D simulation of different shock-wave experiments. The choosing of initial parameters, the modeling itself and output data treatment can be made directly via the Internet. The interface is based upon the expert system on shock-wave data and equations of state and contains both the Eulerian and Lagrangian Godunov hydrocodes. The availability of equations of state for a broad set of substances makes this system a useful tool for planning and interpretation of shock-wave experiments. As an example of simulation with the system, results of modeling of multistep shock loading of potassium between polytetrafluoroethylene and stainless steel plates are presented in comparison with experimental data from Shakhray et al.(2005).

  12. A novel CMOS digital pixel sensor for 1D barcode scanning

    NASA Astrophysics Data System (ADS)

    Yan, Mei; DeGeronimo, Gianluigi; O'Connor, Paul; Carlson, Bradley S.

    2004-06-01

    A 1-D CMOS digital pixel image sensor system architecture is presented. Each pixel contains a photodiode, a low-power charge-sensitive amplifier, low noise sample/hold circuit, an 8-bit single-slope ADC, a 12-bit shift register and timing & control logic. The pixel is laid out on a 4μm pitch to enable a cost efficient implementation of high-resolution pixel arrays. Fixed pattern noise (FPN) is reduced by a charge-sensitive feedback amplifier, and the reset noise is cancelled by correlated double sampling read out. A prototype chip containing 512 pixels has been fabricated in the TSMC .25um logic process. A 40μV/e- conversion gain is measured with 100 e- rms read noise.

  13. Statistics of scattered photons from a driven three-level emitter in 1D open space

    SciTech Connect

    Roy, Dibyendu; Bondyopadhaya, Nilanjan

    2014-01-07

    We derive the statistics of scattered photons from a Λ- or ladder-type three-level emitter (3LE) embedded in a 1D open waveguide. The weak probe photons in the waveguide are coupled to one of the two allowed transitions of the 3LE, and the other transition is driven by a control beam. This system shows electromagnetically induced transparency (EIT) which is accompanied with the Autler-Townes splitting (ATS) at a strong driving by the control beam, and some of these effects have been observed recently. We show that the nature of second-order coherence of the transmitted probe photons near two-photon resonance changes from bunching to antibunching to constant as strength of the control beam is ramped up from zero to a higher value where the ATS appears.

  14. Quantum Diffusion on Molecular Tubes: Universal Scaling of the 1D to 2D Transition

    NASA Astrophysics Data System (ADS)

    Chuang, Chern; Lee, Chee Kong; Moix, Jeremy M.; Knoester, Jasper; Cao, Jianshu

    2016-05-01

    The transport properties of disordered systems are known to depend critically on dimensionality. We study the diffusion coefficient of a quantum particle confined to a lattice on the surface of a tube, where it scales between the 1D and 2D limits. It is found that the scaling relation is universal and independent of the temperature, disorder, and noise parameters, and the essential order parameter is the ratio between the localization length in 2D and the circumference of the tube. Phenomenological and quantitative expressions for transport properties as functions of disorder and noise are obtained and applied to real systems: In the natural chlorosomes found in light-harvesting bacteria the exciton transfer dynamics is predicted to be in the 2D limit, whereas a family of synthetic molecular aggregates is found to be in the homogeneous limit and is independent of dimensionality.

  15. Quantum Diffusion on Molecular Tubes: Universal Scaling of the 1D to 2D Transition.

    PubMed

    Chuang, Chern; Lee, Chee Kong; Moix, Jeremy M; Knoester, Jasper; Cao, Jianshu

    2016-05-13

    The transport properties of disordered systems are known to depend critically on dimensionality. We study the diffusion coefficient of a quantum particle confined to a lattice on the surface of a tube, where it scales between the 1D and 2D limits. It is found that the scaling relation is universal and independent of the temperature, disorder, and noise parameters, and the essential order parameter is the ratio between the localization length in 2D and the circumference of the tube. Phenomenological and quantitative expressions for transport properties as functions of disorder and noise are obtained and applied to real systems: In the natural chlorosomes found in light-harvesting bacteria the exciton transfer dynamics is predicted to be in the 2D limit, whereas a family of synthetic molecular aggregates is found to be in the homogeneous limit and is independent of dimensionality. PMID:27232033

  16. A low power, area efficient fpga based beamforming technique for 1-D CMUT arrays.

    PubMed

    Joseph, Bastin; Joseph, Jose; Vanjari, Siva Rama Krishna

    2015-08-01

    A low power area efficient digital beamformer targeting low frequency (2MHz) 1-D linear Capacitive Micromachined Ultrasonic Transducer (CMUT) array is developed. While designing the beamforming logic, the symmetry of the CMUT array is well exploited to reduce the area and power consumption. The proposed method is verified in Matlab by clocking an Arbitrary Waveform Generator(AWG). The architecture is successfully implemented in Xilinx Spartan 3E FPGA kit to check its functionality. The beamforming logic is implemented for 8, 16, 32, and 64 element CMUTs targeting Application Specific Integrated Circuit (ASIC) platform at Vdd 1.62V for UMC 90nm technology. It is observed that the proposed architecture consumes significantly lesser power and area (1.2895 mW power and 47134.4 μm(2) area for a 64 element digital beamforming circuit) compared to the conventional square root based algorithm.

  17. Quasi 1-D Analysis of a Circular, Compressible, Turbulent Jet Laden with Water Droplets. Appendix C

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Recent experimental studies indicate that presence of small amount of liquid droplets reduces the Overall Sound Pressure Level (OASPL) of a jet. Present study is aimed at numerically investigating the effect of liquid particles on the overall flow quantities of a heated, compressible round jet. The jet is assumed perfectly expanded. A quasi-1D model was developed for this purpose which uses area-averaged quantities that satisfy integral conservation equations. Special attention is given to represent the early development region since it is acoustically important. Approximate velocity and temperature profiles were assumed in this region to evaluate entrainment rate. Experimental correlations were used to obtain spreading rate of shear layer. The base flow thus obtained is then laden with water droplets at the exit of the nozzle. Mass, momentum and energy coupling between the two phases is represented using empirical relations. Droplet size and mass loading are varied to observe their effect on flow variables.

  18. A low power, area efficient fpga based beamforming technique for 1-D CMUT arrays.

    PubMed

    Joseph, Bastin; Joseph, Jose; Vanjari, Siva Rama Krishna

    2015-08-01

    A low power area efficient digital beamformer targeting low frequency (2MHz) 1-D linear Capacitive Micromachined Ultrasonic Transducer (CMUT) array is developed. While designing the beamforming logic, the symmetry of the CMUT array is well exploited to reduce the area and power consumption. The proposed method is verified in Matlab by clocking an Arbitrary Waveform Generator(AWG). The architecture is successfully implemented in Xilinx Spartan 3E FPGA kit to check its functionality. The beamforming logic is implemented for 8, 16, 32, and 64 element CMUTs targeting Application Specific Integrated Circuit (ASIC) platform at Vdd 1.62V for UMC 90nm technology. It is observed that the proposed architecture consumes significantly lesser power and area (1.2895 mW power and 47134.4 μm(2) area for a 64 element digital beamforming circuit) compared to the conventional square root based algorithm. PMID:26737263

  19. Survey of Multi-Material Closure Models in 1D Lagrangian Hydrodynamics

    SciTech Connect

    Maeng, Jungyeoul Brad; Hyde, David Andrew Bulloch

    2015-07-28

    Accurately treating the coupled sub-cell thermodynamics of computational cells containing multiple materials is an inevitable problem in hydrodynamics simulations, whether due to initial configurations or evolutions of the materials and computational mesh. When solving the hydrodynamics equations within a multi-material cell, we make the assumption of a single velocity field for the entire computational domain, which necessitates the addition of a closure model to attempt to resolve the behavior of the multi-material cells’ constituents. In conjunction with a 1D Lagrangian hydrodynamics code, we present a variety of both the popular as well as more recently proposed multi-material closure models and survey their performances across a spectrum of examples. We consider standard verification tests as well as practical examples using combinations of fluid, solid, and composite constituents within multi-material mixtures. Our survey provides insights into the advantages and disadvantages of various multi-material closure models in different problem configurations.

  20. Statistical investigation and thermal properties for a 1-D impact system with dissipation

    NASA Astrophysics Data System (ADS)

    Díaz I., Gabriel; Livorati, André L. P.; Leonel, Edson D.

    2016-05-01

    The behavior of the average velocity, its deviation and average squared velocity are characterized using three techniques for a 1-D dissipative impact system. The system - a particle, or an ensemble of non-interacting particles, moving in a constant gravitation field and colliding with a varying platform - is described by a nonlinear mapping. The average squared velocity allows to describe the temperature for an ensemble of particles as a function of the parameters using: (i) straightforward numerical simulations; (ii) analytically from the dynamical equations; (iii) using the probability distribution function. Comparing analytical and numerical results for the three techniques, one can check the robustness of the developed formalism, where we are able to estimate numerical values for the statistical variables, without doing extensive numerical simulations. Also, extension to other dynamical systems is immediate, including time dependent billiards.

  1. 1D accretion discs around eccentric planets: observable near-infrared variability

    NASA Astrophysics Data System (ADS)

    Dunhill, A. C.

    2015-03-01

    I present the results of 1D models of circumplanetary discs around planets on eccentric orbits. I use a classical viscous heating model to calculate emission fluxes at the wavelengths targeted by the NIRCam instrument on JWST, and compare the variability of this signal with the published NIRCam sensitivity specifications. This variability is theoretically detectable by JWST for a sufficiently viscous disc (α ˜ 10-2) around a sufficiently eccentric planet (e ˜ 0.1-0.2) and if the circumplanetary disc accretes material from its parent disc at a rate dot{M} ≳ 10^{-7} M_{⊙} yr-1. I discuss the limitations of the models used, and the implications of the result for probing the effectiveness of disc interactions for growing a planet's orbital eccentricity.

  2. Continuous 1D-Metallic Microfibers Web for Flexible Organic Solar Cells.

    PubMed

    Hong, Kihyon; Ham, Juyoung; Kim, Byoung-Joon; Park, Jae Yong; Lim, Dong Chan; Lee, Joo Yul; Lee, Jong-Lam

    2015-12-16

    We report the use of a continuous 1D-metallic microfibers web (MFW) as transparent electrode for organic solar cells (OSCs). The MFW electrode can be produced with a process that involves simple electrospinning and wet etching of metal thin film. Au MFW exhibits a maximum optical transmittance of 90.8% (at 15 Ω/sq of the sheet resistance) and excellent mechanical flexibility. The MFW structure has an average width in the range from 4 to 6 μm and a junction-free structure, resulting in very smooth surface roughness. The OSCs with Au MFW electrode exhibited a higher power conversion efficiency (PCE) of 3.50% than the device with an indium tin oxide electrode (PCE = 3.20%). The optical modeling calculation showed that the Au MFW electrode induced light scattering and improved the light absorption in the active layer, resulting in an improved PCE in the OSCs.

  3. Experimental investigations of heat transport dynamics in a 1D porous medium column

    NASA Astrophysics Data System (ADS)

    Cherubini, Claudia; Pastore, Nicola; Giasi, Concetta I.; Allegretti, Nicoletta M.

    2016-04-01

    A laboratory physical model has been set up to analyse the forced convective flow and the related heat transport dynamics through a 1d porous medium column. In particular, the experiments regard the observation of thermal breakthrough curves obtained through a continuous flow injection in correspondence of eight thermocouple positioned uniformly along a thermally isolated column of porous medium. The experiment has been conducted for different flow rates in order to investigate the critical issues regarding heat transport phenomena such as the influence of non-linear flow regime, the relationship between the thermal dispersion with the flow velocity and the validity of the local thermal equilibrium assumption between the fluid and solid phase. The results emphasize the magnitude of the errors of the commonly used assumptions in the numerical modelling of heat transport.

  4. Quantum propagation and confinement in 1D systems using the transfer-matrix method

    NASA Astrophysics Data System (ADS)

    Pujol, Olivier; Carles, Robert; Pérez, José-Philippe

    2014-05-01

    The aim of this article is to provide some Matlab scripts to the teaching community in quantum physics. The scripts are based on the transfer-matrix formalism and offer a very efficient and versatile tool to solve problems of a physical object (electron, proton, neutron, etc) with one-dimensional (1D) stationary potential energy. Resonant tunnelling through a multiple-barrier or confinement in wells of various shapes is particularly analysed. The results are quantitatively discussed with semiconductor heterostructures, harmonic and anharmonic molecular vibrations, or neutrons in a gravity field. Scripts and other examples (hydrogen-like ions and transmission by a smooth variation of potential energy) are available freely at http://www-loa.univ-lille1.fr/˜pujol in three languages: English, French and Spanish.

  5. Vibron properties in quasi 1D molecular structures: the case of two parallel unshifted macromolecuar chains

    NASA Astrophysics Data System (ADS)

    Čevizović, D.; Petković, S.; Galović, S.; Reshetnyak, A.; Chizhov, A.

    2016-01-01

    We study the hopping mechanism of the vibron excitation transport in the system of two parallel unshifted 1D macromolecuar chains in the framework of non-adiabatic polaron theory. We suppose that the vibron interaction with thermal oscillations of the macromolecular structural elements will result in vibron self-trapping and the formation of the partial dressed vibron state. We also suppose that quasiparticle motion takes place via a sequence of random sitejumps, in each of which the quasiparticle can migrate either to the first neighbor site of the macromolecular chain. With use of the modified Holstein polaron model, we calculate the vibron effective mass in dependence of the basic system parameters and temperature. Special attention is paid to the influence of interchain coupling on vibron dressing. We find that for certain values of the system parameters the quasiparticle mass abruptly changes.

  6. Pressure Sensor via Optical Detection Based on a 1D Spin Transition Coordination Polymer

    PubMed Central

    Jureschi, Cătălin M.; Linares, Jorge; Rotaru, Aurelian; Ritti, Marie Hélène; Parlier, Michel; Dîrtu, Marinela M.; Wolff, Mariusz; Garcia, Yann

    2015-01-01

    We have investigated the suitability of using the 1D spin crossover coordination polymer [Fe(4-(2′-hydroxyethyl)-1,2,4-triazole)3]I2·H2O, known to crossover around room temperature, as a pressure sensor via optical detection using various contact pressures up to 250 MPa. A dramatic persistent colour change is observed. The experimental data, obtained by calorimetric and Mössbauer measurements, have been used for a theoretical analysis, in the framework of the Ising-like model, of the thermal and pressure induced spin state switching. The pressure (P)-temperature (T) phase diagram calculated for this compound has been used to obtain the P-T bistability region. PMID:25621610

  7. Fluid friction and wall viscosity of the 1D blood flow model.

    PubMed

    Wang, Xiao-Fei; Nishi, Shohei; Matsukawa, Mami; Ghigo, Arthur; Lagrée, Pierre-Yves; Fullana, Jose-Maria

    2016-02-29

    We study the behavior of the pulse waves of water into a flexible tube for application to blood flow simulations. In pulse waves both fluid friction and wall viscosity are damping factors, and difficult to evaluate separately. In this paper, the coefficients of fluid friction and wall viscosity are estimated by fitting a nonlinear 1D flow model to experimental data. In the experimental setup, a distensible tube is connected to a piston pump at one end and closed at another end. The pressure and wall displacements are measured simultaneously. A good agreement between model predictions and experiments was achieved. For amplitude decrease, the effect of wall viscosity on the pulse wave has been shown as important as that of fluid viscosity.

  8. Markov Chain Monte Carlo Sampling Methods for 1D Seismic and EM Data Inversion

    2008-09-22

    This software provides several Markov chain Monte Carlo sampling methods for the Bayesian model developed for inverting 1D marine seismic and controlled source electromagnetic (CSEM) data. The current software can be used for individual inversion of seismic AVO and CSEM data and for joint inversion of both seismic and EM data sets. The structure of the software is very general and flexible, and it allows users to incorporate their own forward simulation codes and rockmore » physics model codes easily into this software. Although the softwae was developed using C and C++ computer languages, the user-supplied codes can be written in C, C++, or various versions of Fortran languages. The software provides clear interfaces for users to plug in their own codes. The output of this software is in the format that the R free software CODA can directly read to build MCMC objects.« less

  9. On a 1D nonlocal transport equation with nonlocal velocity and subcritical or supercritical diffusion

    NASA Astrophysics Data System (ADS)

    Lazar, Omar

    2016-11-01

    We study a 1D transport equation with nonlocal velocity with subcritical or supercritical dissipation. For all data in the weighted Sobolev space Hk (wλ,κ) ∩L∞, where k = max ⁡ (0 , 3 / 2 - α) and wλ,κ is a given family of Muckenhoupt weights, we prove a global existence result in the subcritical case α ∈ (1 , 2). We also prove a local existence theorem for large data in H2 (wλ,κ) ∩L∞ in the supercritical case α ∈ (0 , 1). The proofs are based on the use of the weighted Littlewood-Paley theory, interpolation along with some new commutator estimates.

  10. Revisiting the Anderson Model with Power-Law Correlated Disorder in 1D and 2D

    NASA Astrophysics Data System (ADS)

    Petersen, Greg; Sandler, Nancy

    2011-03-01

    The dimensionality of a disordered system directly affects the critical energy where a localization/delocalization transition occurs. In non-interacting systems with uncorrelated disorder, it is widely known that all states in one-dimension are localized. However, for some correlations there exist transition energies similar to mobility edges or small subsets of extended states that are robust against disorder. In this talk, we will present results on the diffusion of a wavepacket in a power-law correlated random potential of the form < V (r) V (0) > =1/(a + r)α . We also report results for the participation ratio Pr =1/N 2 < |ai |4 > . Preliminary results for 1D chains support the existence of a mobility edge near the band center. Square and graphene lattices will also be discussed. This work has been supported by the NSF-PIRE mwn/ciam and NSF Grant DMR-0710581.

  11. Controlling Orientational Order in 1-D Assemblies of Multivalent Triangular Prisms.

    PubMed

    Kohlstedt, Kevin L; Olvera de la Cruz, Monica; Schatz, George C

    2013-01-01

    Multivalent nanostructures are becoming an increasingly important player in the self-assembly of supramolecular lattices. Understanding the role that shape plays in the coordination of the assemblies is crucial for the functional response of the material. We develop a simple design rule for the assembly of multivalent Au triangular nanoprisms into 1-D ordered arrays based on both the length of the valent DNA and the aspect ratio of the prism. Using MD simulations, we describe an order parameter that captures the short-range order of the assembly controlled by the design parameters. The order parameter shows that even short chains (N = 4) of prisms have a high degree of orientational order that transitions to no orientational order when the DNA length is similar to the prism length. Unlike isotropic polyvalent assemblies, we find that the highly oriented chains of prisms lose orientational order in discrete steps during melting as the prisms in the arrays dissociate.

  12. Long distance transport of ultracold atoms using a 1D optical lattice

    NASA Astrophysics Data System (ADS)

    Schmid, Stefan; Thalhammer, Gregor; Winkler, Klaus; Lang, Florian; Hecker Denschlag, Johannes

    2006-08-01

    We study the horizontal transport of ultracold atoms over macroscopic distances of up to 20 cm with a moving 1D optical lattice. By using an optical Bessel beam to form the optical lattice, we can achieve nearly homogeneous trapping conditions over the full transport length, which is crucial in order to hold the atoms against gravity for such a wide range. Fast transport velocities of up to 6 m s-1 (corresponding to about 1100 photon recoils) and accelerations of up to 2600 m s-2 are reached. Even at high velocities the momentum of the atoms is precisely defined with an uncertainty of less than one photon recoil. This allows for construction of an atom catapult with high kinetic energy resolution, which might have applications in novel collision experiments.

  13. Alpha 1D- and alpha 1A-adrenoceptors mediate contraction in rat renal artery.

    PubMed

    Villalobos-Molina, R; López-Guerrero, J J; Ibarra, M

    1997-03-19

    To investigate the alpha 1-adrenoceptor subtype(s) mediating contraction in rat renal artery, we have compared the effect of the alpha 1-adrenoceptor antagonists, 5-methylurapidil, BMY 7378 (8-(2-(4-(2-methoxyphenyl)-1-piperazinyl) ethyl) 8-azaspiro (4.5) decane-7,9-dione 2HCl) and chloroethylclonidine on functional responses to noradrenaline. A clear blockade by chloroethylclonidine (10(-4) M) of noradrenaline-induced contraction was observed and, along with this effect. pKB values of 9.12 and 8.40 for BMY 7378 and 9.75 and 10.06 for 5-methylurapidil were obtained, indicating that the renal artery expresses the alpha 1D-adrenoceptor subtype as the one involved in contraction and not only the alpha 1A subtype as has been reported. PMID:9098691

  14. Minimum 1-D P-wave velocity reference model for Northern Iran

    NASA Astrophysics Data System (ADS)

    Rezaeifar, Meysam; Diehl, Tobias; Kissling, Edi

    2016-04-01

    Uniform high-precision earthquake location is of importance in a seismically active area like northern Iran where the earthquake catalogue is a prerequisite for seismic hazard assessment and tectonic interpretation. We compile a complete and consistent local earthquake data set for the northern Iran region, using information from two independently operating seismological networks, Iran Seismological Center (IRSC) network, administered by the Geophysical Institute of Tehran University, and Iran Broadband network administered by International Institute of Engineering Earthquake and Seismology (IIEES). Special care is taken during the merging process to reduce the number of errors in the data, including station parameters, event pairing, phase identification, and to the assessment of quantitative observation uncertainties. The derived P-wave 1D-velocity model for Northern Iran may serve for consistent routine high-precision earthquake location and as initial reference model for 3D seismic tomography.

  15. Cooperative microexcitations in 2+1D chain-bundle dusty plasma liquids

    SciTech Connect

    Io, C.-W.; Chan, C.-L.; Lin I

    2010-05-15

    Through direct visualization at the discrete level, the microexcitations in cold 2+1D dusty plasma liquids formed by negatively charged dusts suspended in low pressure gaseous discharges were experimentally investigated, in which the downward ion flow wake field induces strong vertical coupling and chain bundle structure. It is found that the horizontal structure and motion are similar to those of the two-dimensional liquid. Different types of basic cooperative chain excitations: straight vertical chains with small amplitude jittering, chain tilting-restraightening, bundle twisting-restraightening, and chain breaking-reconnection, are observed. The region with good (poor) horizontal structural order prefers the straight (tilted or broken) chains with little (large) titling and tilting rate.

  16. Quantum simulation of 2D topological physics in a 1D array of optical cavities.

    PubMed

    Luo, Xi-Wang; Zhou, Xingxiang; Li, Chuan-Feng; Xu, Jin-Shi; Guo, Guang-Can; Zhou, Zheng-Wei

    2015-07-06

    Orbital angular momentum of light is a fundamental optical degree of freedom characterized by unlimited number of available angular momentum states. Although this unique property has proved invaluable in diverse recent studies ranging from optical communication to quantum information, it has not been considered useful or even relevant for simulating nontrivial physics problems such as topological phenomena. Contrary to this misconception, we demonstrate the incredible value of orbital angular momentum of light for quantum simulation by showing theoretically how it allows to study a variety of important 2D topological physics in a 1D array of optical cavities. This application for orbital angular momentum of light not only reduces required physical resources but also increases feasible scale of simulation, and thus makes it possible to investigate important topics such as edge-state transport and topological phase transition in a small simulator ready for immediate experimental exploration.

  17. Cooperative microexcitations in 2+1D chain-bundle dusty plasma liquids

    NASA Astrophysics Data System (ADS)

    Io, Chong-Wai; Chan, Chia-Ling; I, Lin

    2010-05-01

    Through direct visualization at the discrete level, the microexcitations in cold 2+1D dusty plasma liquids formed by negatively charged dusts suspended in low pressure gaseous discharges were experimentally investigated, in which the downward ion flow wake field induces strong vertical coupling and chain bundle structure. It is found that the horizontal structure and motion are similar to those of the two-dimensional liquid. Different types of basic cooperative chain excitations: straight vertical chains with small amplitude jittering, chain tilting-restraightening, bundle twisting-restraightening, and chain breaking-reconnection, are observed. The region with good (poor) horizontal structural order prefers the straight (tilted or broken) chains with little (large) titling and tilting rate.

  18. Antiplane analysis for an elliptical inclusion in 1D hexagonal piezoelectric quasicrystal composites

    NASA Astrophysics Data System (ADS)

    Guo, Junhong; Zhang, Zhiying; Xing, Yongming

    2016-02-01

    An elliptical inclusion embedded in an infinite 1D hexagonal piezoelectric quasicrystal matrix is analysed in the framework of linear piezoelasticity of quasicrystals. Using the technique of conformal mapping, the closed-form solutions of the complex potentials, all the field quantities in the matrix and the inclusion are obtained under far-field antiplane mechanical loads of the phonon and phason fields and an inplane electrical load. Several special cases, such as a homogeneous material, a soft and permeable inclusion, an impermeable inclusion, a line inclusion, a rigid inclusion and a crack are reduced by the present results. Some numerical examples are provided to shows the variations of the stresses of the phonon and phason fields and the electric field with the shape of hole/inclusion, the dielectric permittivity and the distance from the hole/inclusion.

  19. Application of MSOR iteration with Newton scheme for solutions of 1D nonlinear porous medium equations

    NASA Astrophysics Data System (ADS)

    Chew, J. V. L.; Sulaiman, J.

    2016-06-01

    This paper considers Newton-MSOR iterative method for solving 1D nonlinear porous medium equation (PME). The basic concept of proposed iterative method is derived from a combination of one step nonlinear iterative method which known as Newton method with Modified Successive Over Relaxation (MSOR) method. The reliability of Newton-MSOR to obtain approximate solution for several PME problems is compared with Newton-Gauss-Seidel (Newton-GS) and Newton-Successive Over Relaxation (Newton-SOR). In this paper, the formulation and implementation of these three iterative methods have also been presented. From four examples of PME problems, numerical results showed that Newton-MSOR method requires lesser number of iterations and computational time as compared with Newton-GS and Newton-SOR methods.

  20. Spoof plasmon resonance with 1D periodic grooves for terahertz refractive index sensing

    NASA Astrophysics Data System (ADS)

    Zhang, Yusheng; Hong, Zhi; Han, Zhanghua

    2015-04-01

    We analyze the use of spoof plasmon resonance due to the excitation of spoof surface plasmons in a 1D array of rectangular grooves for terahertz refractive index sensing in an Otto configuration. The dependence of the resonant angle on the change of the refractive index is numerically investigated and a high angular sensitivity about S=320°/RIU is demonstrated, which leads to a high resolution of 3×10-7 RIU assuming 1×10-4 degree for angular resolution. We further show that by using a slanted geometry an even higher sensitivity up to 452°/RIU can be achieved. These results provide a novel method for terahertz refractive index sensing.

  1. Challenges and future directions of the T1D Exchange Clinic Network and registry.

    PubMed

    Miller, Kellee M; Xing, Dongyuan; Tamborlane, William V; Bergenstal, Richard M; Beck, Roy W

    2013-07-01

    The T1D Exchange Clinic Network consists of 67 clinics throughout the United States. Among the more than 100,000 patients with type 1 diabetes mellitus (T1DM) who receive care at these centers, more than 26,000 have been enrolled in a registry. The registry includes participants over a wide age range, from age <1 to 93 years, and consists of both those newly diagnosed (more than 3000 diagnosed <1 year from the time of enrollment) and those with long-standing diabetes (more than 1000 with T1DM for at least 40 years). Data on diabetes history, insulin administration, diabetes management, monitoring, complications, medical conditions, medications, and laboratory results are collected at enrollment and annually through participant completion of Web-based questionnaires and data extraction from medical records. The clinic registry has provided a rich data set to address important clinical and public health issues, including important observations regarding the current state of treatment of T1DM in diabetes centers in the United States. Challenges encountered during the establishment of the clinic registry include establishment of criteria for a diagnosis of presumed autoimmune T1DM, standardization of data collected across clinics, data quality, and understanding of potential bias. Collecting the data and maximizing data quality has required considerable effort. Even with these efforts, certain data elements are difficult to capture in a meaningful way. A standard T1DM module used by all electronic health records could be developed based on the data collection instruments developed for the T1D Exchange clinic registry.

  2. Signal-noise separation based on self-similarity testing in 1D-timeseries data

    NASA Astrophysics Data System (ADS)

    Bourdin, Philippe A.

    2015-08-01

    The continuous improvement of the resolution delivered by modern instrumentation is a cost-intensive part of any new space- or ground-based observatory. Typically, scientists later reduce the resolution of the obtained raw-data, for example in the spatial, spectral, or temporal domain, in order to suppress the effects of noise in the measurements. In practice, only simple methods are used that just smear out the noise, instead of trying to remove it, so that the noise can nomore be seen. In high-precision 1D-timeseries data, this usually results in an unwanted quality-loss and corruption of power spectra at selected frequency ranges. Novel methods exist that are based on non-local averaging, which would conserve much of the initial resolution, but these methods are so far focusing on 2D or 3D data. We present here a method specialized for 1D-timeseries, e.g. as obtained by magnetic field measurements from the recently launched MMS satellites. To identify the noise, we use a self-similarity testing and non-local averaging method in order to separate different types of noise and signals, like the instrument noise, non-correlated fluctuations in the signal from heliospheric sources, and correlated fluctuations such as harmonic waves or shock fronts. In power spectra of test data, we are able to restore significant parts of a previously know signal from a noisy measurement. This method also works for high frequencies, where the background noise may have a larger contribution to the spectral power than the signal itself. We offer an easy-to-use software tools set, which enables scientists to use this novel technique on their own noisy data. This allows to use the maximum possible capacity of the instrumental hardware and helps to enhance the quality of the obtained scientific results.

  3. Optimal modeling of 1D azimuth correlations in the context of Bayesian inference

    NASA Astrophysics Data System (ADS)

    De Kock, Michiel B.; Eggers, Hans C.; Trainor, Thomas A.

    2015-09-01

    Analysis and interpretation of spectrum and correlation data from high-energy nuclear collisions is currently controversial because two opposing physics narratives derive contradictory implications from the same data, one narrative claiming collision dynamics is dominated by dijet production and projectile-nucleon fragmentation, the other claiming collision dynamics is dominated by a dense, flowing QCD medium. Opposing interpretations seem to be supported by alternative data models, and current model-comparison schemes are unable to distinguish between them. There is clearly need for a convincing new methodology to break the deadlock. In this study we introduce Bayesian inference (BI) methods applied to angular correlation data as a basis to evaluate competing data models. For simplicity the data considered are projections of two-dimensional (2D) angular correlations onto a 1D azimuth from three centrality classes of 200-GeV Au-Au collisions. We consider several data models typical of current model choices, including Fourier series (FS) and a Gaussian plus various combinations of individual cosine components. We evaluate model performance with BI methods and with power-spectrum analysis. We find that FS-only models are rejected in all cases by Bayesian analysis, which always prefers a Gaussian. A cylindrical quadrupole cos(2 ϕ ) is required in some cases but rejected for 0%-5%-central Au-Au collisions. Given a Gaussian centered at the azimuth origin, "higher harmonics" cos(m ϕ ) for m >2 are rejected. A model consisting of Gaussian +dipole cos(ϕ )+quadrupole cos(2 ϕ ) provides good 1D data descriptions in all cases.

  4. Evaluation of the Transport of Natural Radioactive Materials in Large Lysimeters Using Hydrus-1D

    NASA Astrophysics Data System (ADS)

    Pontedeiro, E.; Cipriani, M.; van Genuchten, M.; Simunek, J.

    2007-12-01

    The mining industry in Brazil often uses raw materials that contain relatively high concentrations of naturally occurring radioactive materials (referred to as NORM). Ores of relatively low grade typically are used to produce refined metals of high purity (e.g., Nb, Ta, Sn, and Au) using pyrometallurgic processes. The final waste is a slag rich in natural radioactive contaminants (the U and Th decay series), which are then usually deposited in industrial landfills. To study the long-term fate and transport of radionuclides leached from the NORM wastes, several large (3 m deep) lysimeters were constructed at the Pocos de Caldas Laboratory of the Brazilian Nuclear Energy Commision (CNEN). The lysimeters were packed with surface soils and slags from one of the mining sites in South East Brazil. Main purpose of our lysimeter experiments was to follow the dissolution and transport of radionuclides from the slags under natural climatic conditions. Leaching rates and radionuclide concentrations of the effluent were observed during a three-year time period. A variety of physical and chemical properties of the soils and slags (including laboratory batch equilibrium sorption values) were also determined. The data were analyzed using several computer software packages, including the STANMOD code for analytical modeling of decay chain transport during steady flow, the HYDRUS-1D code for variably-saturated flow and the transport of multiple solutes, and the HP1 code for a more comprehensive analysis of the geochemistry involved. In this presentation we describe the experimental setup and provide preliminary results of the theoretical analyses, especially those using HYDRUS-1D.

  5. Exploring triggers for polar tropospheric ODEs, using a 1-D snow photochemistry model (MISTRA-SNOW).

    NASA Astrophysics Data System (ADS)

    Buys, Z.; Jones, A. E.; von Glasow, R.

    2012-04-01

    Tropospheric Ozone Depletion Events (ODEs) have been known to occur in polar regions for over 20 years. During such events, ozone concentrations can fall from background amounts to below instrumental detection limits within a few minutes and remain suppressed for on the order of hours to days. The chemical destruction of ozone is driven by halogens (especially bromine radicals) that have a source associated with the sea ice zone. Although our knowledge of ODEs has increased greatly since their discovery, some of the key processes involved are not yet fully understood. We now know that heterogeneous reactions lead to the activation of Br2 and BrCI, via uptake of HOBr onto aqueous salt solutions /aerosol/ surface snowpack (Fickert et al., 1999), and it is widely accepted that bromine catalytic reaction cycles (the 'bromine explosion') in the gas phase are responsible for surface ozone destruction (Simpson et al., 2007). There is still much debate over the source of bromine in the atmosphere that drives ODEs, but there is strong evidence to suggest a source associated with the sea ice zone. A 1D Marine Boundary Layer (MBL) chemistry model (MISTRA; von Glasow et al., 2002) has been modified to be representative of Antarctic conditions. The chemistry module includes chemical reactions in the gas phase, in and on aerosol particles and takes into account transfer between the gas and aqueous phase. A new snow-photochemistry module has been developed which includes chemistry which takes place in the quasi-liquid layer on aerosol (Thomas et al., 2011), which is of great importance to our understanding of the chemistry which initiates a bromine explosion. Here we use this newly developed 1-D snow photochemistry model (MISTRA-SNOW) to look at some of the suggested triggers for, and the different meteorological conditions required to produce, tropospheric ODEs in polar regions.

  6. Effects of polyamine inhibitors on zinc uptake by COMMA-1D mammary epithelial cells

    SciTech Connect

    Allen, J.C.; Haedrich, L.H. )

    1991-03-15

    Zn uptake or transport is stimulated by glucocorticoids in many types of epithelial cells, including the COMMA-1D mouse mammary cell line. The current objective was to determine whether polyamines also mediate glucocorticoid stimulation of Zn-uptake. Initially, cells grown in lactogenic hormone supplemented-media had approximately 65% greater {sup 65}Zn-uptake over 24 h than cells in nonsupplemented growth media (GM). {sup 65}Zn-uptake from HM with 10{sup {minus}5}M methylglyoxal-bis(guanylhydrazone) (MGBG) (s-adenosyl-methionine decarboxylase inhibitor to block polyamine synthesis) added was less than from GM. Exogenous spermidine added to the MGBG-HM media increased {sup 65}Zn-uptake. However, up to 10mM difluoromethylornithine (DFMO), a more specific inhibitor of sperimidine synthesis, had no significant effect on 24-h {sup 65}Zn-uptake by cells in HM. In GM, DFMO caused a slight dose-dependent decrease in {sup 65}Zn-uptake over the range 10{sup {minus}6} to 5 {times} 10{sup 3}M. Also, with 8 h of incubation, DFMO tended to decrease {sup 65}Zn-uptake in HM-stimulated cells. These data cannot yet distinguish between the possibilities that DFMO is inactivated during the 24-h incubation or that the dramatic effects of MGBG on {sup 65}Zn-uptake in these mammary-derived cells is not related to its inhibition of polyamine synthesis. Because COMMA-1D cells alter Zn uptake in response to lactogenic hormones and MGBG, the model system is suitable for further studies of the mechanisms of zinc transport in epithelia.

  7. 1D crustal structure from quality seismological data for the Cyprus subduction zone

    NASA Astrophysics Data System (ADS)

    Perk, Şükran; Deǧer, Ali; Özbakır, Karabulut, Hayrullah

    2013-04-01

    The eastern Mediterranean is a tectonically complex region, where long-term subduction and accretion processes have shaped the overall evolution. Recently, many seismic tomography studies have shown subducted slabs of the Neo-Tethyan lithosphere, continuing its subduction in the Hellenic trench, stalled in the Cyprus trench and being torn near the intersection between them. Antalya bay is a key region located on the western flank of the Cyprus Subduction Zone (CSZ), close to the junction between the Hellenic and Cyprus Arcs. Here deep earthquakes are nucleated, which otherwise cannot be seen anywhere else along the CSZ. For this reason, we focus our attention specifically to the Antalya Bay area but also the remaining parts of the CSZ. Several regional studies have been carried out to define the velocity structure beneath the region but none have been able to locate the CSZ. One of the main reasons for this was the lack of incorporation of a wide seismic network in those regional studies. We compile a large catalog of seismicity and relocate earthquakes to infer 1D local crustal structure using the clusters of seismicity. We used seismic data between 2005 - 2011 which are recorded at more than 335 seismic stations operated by several agencies and portable deployments. The data-set is composed of over 10,000 events and earthquakes can be grouped in several distinct clusters. We defined five of these clusters, where the total number of events is more than 4500, among which we selected over 2000 events with the highest data quality. 1-D local P-wave velocity models are developed using this high quality data-set and the earthquakes are relocated using the local velocity models. The compiled and reanalyzed data will contribute to perform local earthquake tomography. Moreover, obtained local velocity models represent a fundamental step towards an improved seismic tomography studies in a very crucial region in the eastern Mediterranean.

  8. Community interactive webtool to retrieve Greenland glacier data for 1-D geometry

    NASA Astrophysics Data System (ADS)

    Perrette, Mahé

    2015-04-01

    Marine-terminating, outlet glaciers are challenging to include in conventional Greenland-wide ice sheet models because of the large variation in scale between model grid size (typically 10 km) and outlet glacier width (typically 1-5km), making it a subgrid scale feature. A possible approach to tackle this problem is to use one-dimensional flowline models for the individual glaciers (e.g. Nick et al., 2013, Nature; Enderlin et al 2013a,b, The Cryosphere). Here we present a python- and javascript- based webtool to prepare data required to feed in or validate a flowline model. It is designed primarily to outline the glacier geometry and returns relevant data averaged over cross-sections. The tool currently allows to: visualize 2-D ice sheet data (zoom/pan), quickly switch between datasets (e.g. ice thickness, bedrock elevation, surface velocity) interpolated / transformed on a common grid. draw flowlines from user-input seeds on the map, calculated from a vector field of surface velocity, as an helpful guide for point 3 interactively draw glacier outline (side and middle lines) on top of the data mesh the outlined glacier domain in the horizontal plane extract relevant data into a 1-D longitudinal profile download the result as a netCDF file The project is hosted on github to encourage collaboration, under the open-source MIT Licence. The server-side is written in python (open-source) using the web-framework flask, and the client-side (javascript) makes use of the d3 library for interactive figures. For now it only works locally in a web browser (start server: "python runserver.py"). Data need to be downloaded separately from the original sources. See the README file in the project for information how to use it. Github projects: https://github.com/perrette/webglacier1d (main) https://github.com/perrette/dimarray (dependency)

  9. 1-D and 2-D Probabilistic Inversions of Fault Zone Guided Waves

    NASA Astrophysics Data System (ADS)

    Gulley, A.; Eccles, J. D.; Kaipio, J. P.; Malin, P. E.

    2015-12-01

    Fault Zone Guided Waves (FZGWs) are seismic coda that are trapped by the low velocity damage zone of faults. Inversions of these phases can be carried out using their measured dispersion and a Bayesian probability approach. This method utilises a Markov chain Monte Carlo which allows uncertainties and trade-offs to be quantified. Accordingly we have developed a scheme that estimates the dispersion curve and amplitude response variability from a FZGW record. This method allows the computation of both the point estimates and the covariance of the dispersion curve. The subsequent estimation of fault zone parameters is then based on a Gaussian model for the dispersion curve. We then show that inversions using FZGW dispersion data can only resolve fault zone velocity contrast and fault zone width - it leaves densities, absolute country rock velocities and the earthquake location unresolved. We show that they do however significantly affect the estimated fault zone velocities and widths. As these parameters cannot be resolved, we allow for their effects on the estimates of fault zone width and velocity contrast by using the Bayesian approximation error method. We show that using this method reduces computational time from days to minutes and the associated loss of accuracy is insignificant compared to carrying out the inversion on all parameters. We have extended our scheme to 2-D using 1-D slices. The Bayesian approximation error methodology is further employed to provide a 'correction term' with uncertainty for the 1-D slice approximation. We investigate these features with both synthetic data and FZGW data from the Alpine Fault of New Zealand.

  10. One-dimensional SnF{sub 2} single crystals in the inner channels of single-wall carbon nanotubes: I. Preparation and basic characterization

    SciTech Connect

    Zakalyukin, R. M. Demyanets, L. N.; Kiselev, N. A.; Kumskov, A. S.; Kislov, M. B.; Krestinin, A. V.; Hutchison, J. L.

    2010-05-15

    One-dimensional (1D) SnF{sub 2} single crystals have been obtained by crystallization from melt in the inner channels of single-wall carbon nanotubes (SWCNTs). SWCNTs with an inner diameter of 1.02-1.4 nm, synthesized by electric-arc discharge and chemically purified, were used for incorporation. The synthesized 1D SnF{sub 2} single crystal-SWCNT composites are basically characterized by X-ray diffraction, energy-dispersive analysis, electron microscopy, and chemical analysis. The characteristic motifs of tin cation distribution in the SWCNT inner channel confirm the formation of SnF{sub 2} single crystals.

  11. Drilling technique for crystals

    NASA Technical Reports Server (NTRS)

    Hunter, T.; Miyagawa, I.

    1977-01-01

    Hole-drilling technique uses special crystal driller in which drill bit rotates at fixed position at speed of 30 rpm while crystal slowly advances toward drill. Technique has been successfully applied to crystal of Rochell salt, Triglycine sulfate, and N-acetyglycine. Technique limits heat buildup and reduces strain on crystal.

  12. Liquid encapsulated crystal growth

    NASA Technical Reports Server (NTRS)

    Morrison, Andrew D. (Inventor)

    1987-01-01

    Low-defect crystals are grown in a closed ampoule under a layer of encapsulant. After crystal growth, the crystal is separated from the melt and moved into the layer of encapsulant and cooled to a first temperature at which crystal growth stops. The crystal is then moved into the inert gas ambient in the ampoule and further cooled. The crystal can be separated from the melt by decanting the melt into and adjacent reservoir or by rotating the ampoule to rotate the crystal into the encapsulant layer.

  13. Liquid encapsulated crystal growth

    NASA Technical Reports Server (NTRS)

    Morrison, Andrew D. (Inventor)

    1989-01-01

    Low-defect crystals are grown in a closed ampoule under a layer of encapsulant. After crystal growth, the crystal is separated from the melt and moved into the layer of encapsulant and cooled to a first temperature at which crystal growth stops. The crystal is then moved into the inert gas ambient in the ampoule and further cooled. The crystal can be separated from the melt by decanting the melt into an adjacent reservoir or by rotating the ampoule to rotate the crystal into the encapsulant layer.

  14. Mixed crystal organic scintillators

    DOEpatents

    Zaitseva, Natalia P; Carman, M Leslie; Glenn, Andrew M; Hamel, Sebastien; Hatarik, Robert; Payne, Stephen A; Stoeffl, Wolfgang

    2014-09-16

    A mixed organic crystal according to one embodiment includes a single mixed crystal having two compounds with different bandgap energies, the organic crystal having a physical property of exhibiting a signal response signature for neutrons from a radioactive source, wherein the signal response signature does not include a significantly-delayed luminescence characteristic of neutrons interacting with the organic crystal relative to a luminescence characteristic of gamma rays interacting with the organic crystal. According to one embodiment, an organic crystal includes bibenzyl and stilbene or a stilbene derivative, the organic crystal having a physical property of exhibiting a signal response signature for neutrons from a radioactive source.

  15. Anti-TGF-β Antibody, 1D11, Ameliorates Glomerular Fibrosis in Mouse Models after the Onset of Proteinuria

    PubMed Central

    Liang, Xiaoyan; Schnaper, H. William; Matsusaka, Taiji; Pastan, Ira; Ledbetter, Steve; Hayashida, Tomoko

    2016-01-01

    Fibrosis is a final common pathway leading to loss of kidney function, in which the fibrogenic cytokine, transforming growth factor β (TGF-β), plays a central role. While previous studies showed that TGF-β antagonism by various means prevents fibrosis in mouse models, clinical approaches based on these findings remain elusive. 1D11 is a neutralizing antibody to all three isoforms of TGF-β. In both adriamycin (ADR)-induced nephropathy and NEP25 podocyte ablation nephropathy, thrice-weekly intraperitoneal administration of 1D11 from the day of disease induction until the mice were sacrificed (day 14 for ADR and day 28 for NEP25), significantly reduced glomerular COL1A2 mRNA accumulation and histological changes. Consistent with our previous findings, proteinuria remained overt in the mice treated with 1D11, suggesting distinct mechanisms for proteinuria and fibrogenesis. Podocyte numbers determined by WT1 staining were significantly reduced in NEP25-model glomeruli as expected, while WT1-positive cells were preserved in mice receiving 1D11. Even when 1D11 was administered after the onset of proteinuria on day 3, 1D11 preserved WT1-positive cell numbers in glomeruli and significantly reduced glomerular scar score (2.5 ± 0.2 [control IgG] vs. 1.8 ± 0.2 [1D11], P < 0.05) and glomerular COL1A2 mRNA expression (19.3 ± 4.4 [control IgG] vs. 8.4 ± 2.4 [1D11] fold increase over the healthy control, P < 0.05). Transmission electron microscopy revealed loss of podocytes and denuded glomerular basement membrane in NEP25 mice with disease, whereas podocytes remained attached to the basement membrane, though effaced and swollen, in those receiving 1D11 from day 3. Together, these data suggest that TGF-β neutralization by 1D11 prevents glomerular fibrosis even when started after the onset of proteinuria. While overt proteinuria and podocyte effacement persist, 1D11 prevents total podocytes detachment, which might be a key event activating fibrogenic events in glomeruli

  16. Impact of Nanosize on Supercapacitance: Study of 1D Nanorods and 2D Thin-Films of Nickel Oxide.

    PubMed

    Patil, Ranjit A; Chang, Cheng-Ping; Devan, Rupesh S; Liou, Yung; Ma, Yuan-Ron

    2016-04-20

    We synthesized unique one-dimensional (1D) nanorods and two-dimensional (2D) thin-films of NiO on indium-tin-oxide thin-films using a hot-filament metal-oxide vapor deposition technique. The 1D nanorods have an average width and length of ∼100 and ∼500 nm, respectively, and the densely packed 2D thin-films have an average thickness of ∼500 nm. The 1D nanorods perform as parallel units for charge storing. However, the 2D thin-films act as one single unit for charge storing. The 2D thin-films possess a high specific capacitance of ∼746 F/g compared to 1D nanorods (∼230 F/g) using galvanostatic charge-discharge measurements at a current density of 3 A/g. Because the 1D NiO nanorods provide more plentiful surface areas than those of the 2D thin-films, they are fully active at the first few cycles. However, the capacitance retention of the 1D nanorods decays faster than that of the 2D thin-films. Also, the 1D NiO nanorods suffer from instability due to the fast electrochemical dissolution and high nanocontact resistance. Electrochemical impedance spectroscopy verifies that the low dimensionality of the 1D NiO nanorods induces the unavoidable effects that lead them to have poor supercapacitive performances. On the other hand, the slow electrochemical dissolution and small contact resistance in the 2D NiO thin-films favor to achieve high specific capacitance and great stability.

  17. Identification of novel isoforms of dairy goat EEF1D and their mRNA expression characterization.

    PubMed

    Zhang, Sihuan; Wu, Xianfeng; Pan, Chuanying; Lei, Chuzhao; Dang, Ruihua; Chen, Hong; Lan, Xianyong

    2016-04-25

    Eukaryotic translation elongation factor 1 delta (EEF1D) gene encodes guanine nucleotide exchange protein eEF1Bδ, which participates in the eukaryotic protein synthesis, and plays important roles in regulating cell cycling and milk production. This study firstly focused on detecting the isoforms of dairy goat EEF1D gene and their mRNA expression characterization. Herein, two novel isoforms, EEF1Da and EEF1Dc, were identified in dairy goat. The entire coding sequences of EEF1Da and EEF1Dc isoforms were 843bp and 267bp in length, respectively. Goat EEF1Da had complete conserved domains of elongation factor 1 (EF1) family, and the evolution of goat EEF1Da isoform was agreed with the evolution of species. Expression pattern analysis of different isoforms revealed relatively ubiquitous expression of EEF1D and EEF1Da. While EEF1Dc only expressed in heart, lung, kidney, adipose and muscle. Combining with the analysis results of cloning, qRT-PCR and bioinformatics, EEF1Da is the major alternative splicing form of EEF1D gene. Interestingly, qRT-PCR result showed that the highest expression of EEF1D was in adipose, which is the major component of mammary. This result was consistent with the early research that EEF1D expressed highly in the mammary, which indicated that EEF1D played a potential key role in regulating adipose development and milk production. All these findings would provide a foundation for the further research of EEF1D gene and development of dairy goat industry. PMID:26794801

  18. Impact of Nanosize on Supercapacitance: Study of 1D Nanorods and 2D Thin-Films of Nickel Oxide.

    PubMed

    Patil, Ranjit A; Chang, Cheng-Ping; Devan, Rupesh S; Liou, Yung; Ma, Yuan-Ron

    2016-04-20

    We synthesized unique one-dimensional (1D) nanorods and two-dimensional (2D) thin-films of NiO on indium-tin-oxide thin-films using a hot-filament metal-oxide vapor deposition technique. The 1D nanorods have an average width and length of ∼100 and ∼500 nm, respectively, and the densely packed 2D thin-films have an average thickness of ∼500 nm. The 1D nanorods perform as parallel units for charge storing. However, the 2D thin-films act as one single unit for charge storing. The 2D thin-films possess a high specific capacitance of ∼746 F/g compared to 1D nanorods (∼230 F/g) using galvanostatic charge-discharge measurements at a current density of 3 A/g. Because the 1D NiO nanorods provide more plentiful surface areas than those of the 2D thin-films, they are fully active at the first few cycles. However, the capacitance retention of the 1D nanorods decays faster than that of the 2D thin-films. Also, the 1D NiO nanorods suffer from instability due to the fast electrochemical dissolution and high nanocontact resistance. Electrochemical impedance spectroscopy verifies that the low dimensionality of the 1D NiO nanorods induces the unavoidable effects that lead them to have poor supercapacitive performances. On the other hand, the slow electrochemical dissolution and small contact resistance in the 2D NiO thin-films favor to achieve high specific capacitance and great stability. PMID:27028491

  19. Identification of novel isoforms of dairy goat EEF1D and their mRNA expression characterization.

    PubMed

    Zhang, Sihuan; Wu, Xianfeng; Pan, Chuanying; Lei, Chuzhao; Dang, Ruihua; Chen, Hong; Lan, Xianyong

    2016-04-25

    Eukaryotic translation elongation factor 1 delta (EEF1D) gene encodes guanine nucleotide exchange protein eEF1Bδ, which participates in the eukaryotic protein synthesis, and plays important roles in regulating cell cycling and milk production. This study firstly focused on detecting the isoforms of dairy goat EEF1D gene and their mRNA expression characterization. Herein, two novel isoforms, EEF1Da and EEF1Dc, were identified in dairy goat. The entire coding sequences of EEF1Da and EEF1Dc isoforms were 843bp and 267bp in length, respectively. Goat EEF1Da had complete conserved domains of elongation factor 1 (EF1) family, and the evolution of goat EEF1Da isoform was agreed with the evolution of species. Expression pattern analysis of different isoforms revealed relatively ubiquitous expression of EEF1D and EEF1Da. While EEF1Dc only expressed in heart, lung, kidney, adipose and muscle. Combining with the analysis results of cloning, qRT-PCR and bioinformatics, EEF1Da is the major alternative splicing form of EEF1D gene. Interestingly, qRT-PCR result showed that the highest expression of EEF1D was in adipose, which is the major component of mammary. This result was consistent with the early research that EEF1D expressed highly in the mammary, which indicated that EEF1D played a potential key role in regulating adipose development and milk production. All these findings would provide a foundation for the further research of EEF1D gene and development of dairy goat industry.

  20. Neurotrophins and cognitive functions in T1D compared with healthy controls: effects of a high-intensity exercise.

    PubMed

    Tonoli, Cajsa; Heyman, Elsa; Buyse, Luk; Roelands, Bart; Piacentini, Maria Francesca; Bailey, Stephen; Pattyn, Nathalie; Berthoin, Serge; Meeusen, Romain

    2015-01-01

    Exercise is known to have beneficial effects on cognitive function. This effect is greatly favored by an exercise-induced increase in neurotrophic factors, such as brain-derived neurotrophic factor (BDNF) and insulin-like growth factor-1 (IGF-1), especially with high-intensity exercises (HIE). As a complication of type 1 diabetes (T1D), a cognitive decline may occur, mostly ascribed to hypoglycaemia and chronic hyperglycaemia. Therefore, the purpose of this study was to examine the effects of acute HIE on cognitive function and neurotrophins in T1D and matched controls. Ten trained T1D (8 males, 2 females) participants and their matched (by age, sex, fitness level) controls were evaluated on 2 occasions after familiarization: a maximal test to exhaustion and an HIE bout (10 intervals of 60 s at 90% of their maximal wattage followed by 60 s at 50 W). Cognitive tests and analyses of serum BDNF, IGF-1, and free insulin were performed before and after HIE and following 30 min of recovery. At baseline, cognitive performance was better in the controls compared with the T1D participants (p < 0.05). After exercise, no significant differences in cognitive performance were detected. BDNF levels were significantly higher and IGF-1 levels were significantly lower in T1D compared with the control group (p < 0.05) at all time points. Exercise increased BDNF and IGF-1 levels in a comparable percentage in both groups (p < 0.05). In conclusion, although resting levels of serum BDNF and IGF-1 were altered by T1D, comparable increasing effects on BDNF and IGF-1 in T1D and healthy participants were found. Therefore, regularly repeating acute HIE could be a promising strategy for brain health in T1D.

  1. One-pot synthesis of size- and morphology-controlled 1-D iron oxide nanochains with manipulated magnetic properties.

    PubMed

    He, Qingliang; Yuan, Tingting; Yan, Xingru; Luo, Zhiping; Haldolaarachchige, Neel; Young, David P; Wei, Suying; Guo, Zhanhu

    2014-01-01

    Polypropylene grafted maleic anhydride (PP-MA, 2500 g mole(-1)) has demonstrated its unique capability to synthesize 1-D ferromagnetic hard (292.7 Oe) γ-Fe2O3 nanochains made of ~24 nm nanoparticles vs. PP-MA with 8000 g mole(-1) for the synthesis of 1-D ferromagnetic soft (70.5 Oe) γ-Fe2O3 nanochains (30 nm) made of flowerlike nanoparticles.

  2. Nanoscale stabilization of zintl compounds: 1D ionic Li-P double helix confined inside a carbon nanotube

    NASA Astrophysics Data System (ADS)

    Ivanov, Alexander S.; Kar, Tapas; Boldyrev, Alexander I.

    2016-02-01

    One-dimensional (1D) ionic nanowires are extremely rare materials due to the difficulty in stabilizing 1D chains of ions under ambient conditions. We demonstrate here a theoretical prediction of a novel hybrid material, a nanotube encapsulated 1D ionic lithium monophosphide (LiP) chain, featuring a unique double-helix structure, which is very unusual in inorganic chemistry. This nanocomposite has been investigated with density functional theory, including molecular dynamics simulations and electronic structure calculations. We find that the formation of the LiP double-helical nanowire is facilitated by strong interactions between LiP and CNTs resulting in a charge transfer. This work suggests that nanostructured confinement may be used to stabilize other polyphosphide 1D chains, thus opening new ways to study the chemistry of zintl compounds at the nanoscale.One-dimensional (1D) ionic nanowires are extremely rare materials due to the difficulty in stabilizing 1D chains of ions under ambient conditions. We demonstrate here a theoretical prediction of a novel hybrid material, a nanotube encapsulated 1D ionic lithium monophosphide (LiP) chain, featuring a unique double-helix structure, which is very unusual in inorganic chemistry. This nanocomposite has been investigated with density functional theory, including molecular dynamics simulations and electronic structure calculations. We find that the formation of the LiP double-helical nanowire is facilitated by strong interactions between LiP and CNTs resulting in a charge transfer. This work suggests that nanostructured confinement may be used to stabilize other polyphosphide 1D chains, thus opening new ways to study the chemistry of zintl compounds at the nanoscale. Electronic supplementary information (ESI) available: Additional DOS, band structures, and Bader charges for LiP@SWCNTs. See DOI: 10.1039/c5nr07713c

  3. Highly Directional 1D Supramolecular Assembly of New Diketopyrrolopyrrole-Based Gel for Organic Solar Cell Applications.

    PubMed

    Thool, Gautam Sheel; Narayanaswamy, K; Venkateswararao, A; Naqvi, Sheerin; Gupta, Vinay; Chand, Suresh; Vivekananthan, V; Koner, Rik Rani; Krishnan, Venkata; Singh, Surya Prakash

    2016-05-01

    A new thermoreversible organogel based on diketopyrrolopyrrole dye (DPP-NCO) is reported for the first time and evolved as a new building block for the fabrication of 1D supramolecular assembly. AFM analysis illustrated that its gel state is composed of different sized 1D rods. DPP-NCO gel used as an additive in organic solar cells yields high efficiency of 7.9% owing to better nanophase separation of its active layer. PMID:27079750

  4. Neurotrophins and cognitive functions in T1D compared with healthy controls: effects of a high-intensity exercise.

    PubMed

    Tonoli, Cajsa; Heyman, Elsa; Buyse, Luk; Roelands, Bart; Piacentini, Maria Francesca; Bailey, Stephen; Pattyn, Nathalie; Berthoin, Serge; Meeusen, Romain

    2015-01-01

    Exercise is known to have beneficial effects on cognitive function. This effect is greatly favored by an exercise-induced increase in neurotrophic factors, such as brain-derived neurotrophic factor (BDNF) and insulin-like growth factor-1 (IGF-1), especially with high-intensity exercises (HIE). As a complication of type 1 diabetes (T1D), a cognitive decline may occur, mostly ascribed to hypoglycaemia and chronic hyperglycaemia. Therefore, the purpose of this study was to examine the effects of acute HIE on cognitive function and neurotrophins in T1D and matched controls. Ten trained T1D (8 males, 2 females) participants and their matched (by age, sex, fitness level) controls were evaluated on 2 occasions after familiarization: a maximal test to exhaustion and an HIE bout (10 intervals of 60 s at 90% of their maximal wattage followed by 60 s at 50 W). Cognitive tests and analyses of serum BDNF, IGF-1, and free insulin were performed before and after HIE and following 30 min of recovery. At baseline, cognitive performance was better in the controls compared with the T1D participants (p < 0.05). After exercise, no significant differences in cognitive performance were detected. BDNF levels were significantly higher and IGF-1 levels were significantly lower in T1D compared with the control group (p < 0.05) at all time points. Exercise increased BDNF and IGF-1 levels in a comparable percentage in both groups (p < 0.05). In conclusion, although resting levels of serum BDNF and IGF-1 were altered by T1D, comparable increasing effects on BDNF and IGF-1 in T1D and healthy participants were found. Therefore, regularly repeating acute HIE could be a promising strategy for brain health in T1D. PMID:25525862

  5. Review, implementation and test of the QAZ1D computational method with a view to wave rotor applications

    NASA Astrophysics Data System (ADS)

    Salacka, T. F.

    1985-12-01

    The QAZ1D method is redeveloped in detail and implemented in a first order, one-dimensional FORTRAN program, EULER-1. The program is tested on the shock tube problem and results are presented for various computational meshes and initial conditions. Based on good results of the EULER-1 code, recommendations are made for future extensions and testing to validate the suitability of the QAZ1D method for wave rotor applications.

  6. Pressure cryocooling protein crystals

    DOEpatents

    Kim, Chae Un; Gruner, Sol M.

    2011-10-04

    Preparation of cryocooled protein crystal is provided by use of helium pressurizing and cryocooling to obtain cryocooled protein crystal allowing collection of high resolution data and by heavier noble gas (krypton or xenon) binding followed by helium pressurizing and cryocooling to obtain cryocooled protein crystal for collection of high resolution data and SAD phasing simultaneously. The helium pressurizing is carried out on crystal coated to prevent dehydration or on crystal grown in aqueous solution in a capillary.

  7. Modeling of Crystallizing Polymer Melts in Electrospinning

    SciTech Connect

    Zhmayev, Eduard; Joo, Yong Lak

    2008-07-07

    In electrospinning, applied electric field elongates a charged fluid jet to produce nanofibers. While most polymer melts result in highly-aligned amorphous structures, some fast-crystallizing polymers such as Nylon can produce semi-crystalline fibers, and by controlling this crystallinity the mechanical properties of electrospun fibers can be tailored. Short inflight residence times, high extensional forces, and radially-uniform stress distributions in electrospinning result in the dominance of flow induced crystallization (FIC) and a nearly 1D microstructure. We present our FIC model based on Kolmogoroff's equation, Hoffman-Lauritzen theory, and key modifications from molecular scale insights to account for flow effects. The model behavior is compared to the conventional Ziabicki FIC model using Nylon-6,6 as the model polymer.

  8. Comparison of 1D and 2D modelling with soil erosion model SMODERP

    NASA Astrophysics Data System (ADS)

    Kavka, Petr; Weyskrabova, Lenka; Zajicek, Jan

    2013-04-01

    The contribution presents a comparison of a runoff simulated by profile method (1D) and spatially distributed method (2D). Simulation model SMODERP is used for calculation and prediction of soil erosion and surface runoff from agricultural land. SMODERP is physically based model that includes the processes of infiltration (Phillips equation), surface runoff (kinematic wave based equation), surface retention, surface roughness and vegetation impact on runoff. 1D model was developed in past, new 2D model was developed in last two years. The model is being developed at the Department of Irrigation, Drainage and Landscape Engineering, Civil Engineering Faculty, CTU in Prague. 2D model was developed as a tool for widespread GIS software ArcGIS. The physical relations were implemented through Python script. This script uses ArcGIS system tools for raster and vectors treatment of the inputs. Flow direction is calculated by Steepest Descent algorithm in the preliminary version of 2D model. More advanced multiple flow algorithm is planned in the next version. Spatially distributed models enable to estimate not only surface runoff but also flow in the rills. Surface runoff is described in the model by kinematic wave equation. Equation uses Manning roughness coefficient for surface runoff. Parameters for five different soil textures were calibrated on the set of forty measurements performed on the laboratory rainfall simulator. For modelling of the rills a specific sub model was created. This sub model uses Manning formula for flow estimation. Numerical stability of the model is solved by Courant criterion. Spatial scale is fixed. Time step is dynamically changed depending on how flow is generated and developed. SMODERP is meant to be used not only for the research purposes, but mainly for the engineering practice. We also present how the input data can be obtained based on available resources (soil maps and data, land use, terrain models, field research, etc.) and how can

  9. External fixator configurations in tibia fractures: 1D optimization and 3D analysis comparison.

    PubMed

    Roseiro, Luis M; Neto, M Augusta; Amaro, Ana; Leal, Rogerio P; Samarra, Miguel C

    2014-01-01

    The use of external fixation devices in orthopedic surgery is very common in open tibial fractures. A properly applied fixator may improve the healing process while one improperly applied might delay the healing process. The several external fixator systems used in clinical today, can be categorized into uniplanar-unilateral, uniplanar-bilateral, biplanar and multiplanar. The stability on the fracture focus and, therefore, the fracture healing process, is related with the type of external fixator configuration that is selected. The aim of this study is to discuss the principles for the successful application of unilateral-uniplanar external fixation, the assembly of its components, for the case of a transverse fractures using computational models. In this context, the fixation stiffness characteristics are evaluated using a simplified 1D finite element model for the tibia and external fixator. The beams are modeled with realistic cross-sectional geometry and material properties instead of a simplified model. The VABS (the Variational Asymptotic Beam Section analysis) methodology is used to compute the cross-sectional model for the generalized Timoshenko model, which was embedded in the finite element solver FEAP. The use of Timoshenko beam theory allows accounting for several kinds of loads, including torsion moments. Optimal design is performed with respect to the assembly of fixator components using a genetic algorithm. The optimization procedure is based on the evaluation of an objective function, which is dependent on the displacement at the fracture focus. The initial and optimal results are compared by performing a 3D analysis, for which different three-dimensional finite element models are created. The geometrical model of a tibia is created on the basis of data acquired by CAT scan, made for a healthy tibia of a 22 year old male. The 3D comparison of the 1D optimal results show a clear improvement on the objective function for the several load cases and

  10. Optical bullets in (2+1)D photonic structures and their interaction with localized defects

    NASA Astrophysics Data System (ADS)

    Dohnal, Tomas

    2005-11-01

    This dissertation studies light propagation in Kerr-nonlinear two dimensional waveguides with a Bragg resonant, periodic structure in the propagation direction. The model describing evolution of the electric field envelopes is the system of 2D Nonlinear Coupled Mode Equations (2D CME). The periodic structure induces a range of frequencies (frequency gap) in which linear waves do not propagate. It is shown that, similarly to the ID case of a fiber grating, the 2D nonlinear system supports localized solitary wave solutions, referred to as 2D gap solitons, which have frequencies inside the linear gap and can travel at, any speed smaller than or equal to the speed of light in the corresponding homogeneous medium. Such solutions are constructed numerically via Newton's iteration. Convergence is obtained only near the upper edge of the gap. Gap solitons with a nonzero velocity are constructed by numerically following a bifurcation curve parameterized by the velocity v. It is shown that gap solitons are saddle points of the corresponding Hamiltonian functional and that no (constrained) local minima of the Hamiltonian exist. The linear stability problem is formulated and reasons for the failure of the standard Hamiltonian PDE approach for determining linear stability are discussed. In the second part of the dissertation interaction of 2D gap solitons with localized defects is studied and trapping of slow enough 2D gap solitons is demonstrated. This study builds on [JOSA B 19, 1635 (2002)], where such trapping of 1D gap solitons is considered. Analogously to this 1D problem trapping in the 2D model is explained as a resonant energy transfer into one or more defect modes existent for the particular defect. For special localized defects exact linear modes are found explicitly via the separation of variables. Numerical computation of linear defect modes is used for more general defects. Corresponding nonlinear modes are then constructed via Newton's iteration by following a

  11. Synthesis and characterization of a 1D chain-like Cu{sub 6} substituted sandwich-type phosphotungstate with pendant dinuclear Cu–azido complexes

    SciTech Connect

    Li, Yan-Ying; Zhao, Jun-Wei; Wei, Qi; Yang, Bai-Feng; Yang, Guo-Yu

    2014-02-15

    A novel Cu–azido complex modified hexa-Cu{sup II} substituted sandwich-type phosphotungstate [Cu(en){sub 2}]([Cu{sub 2}(en){sub 2}(μ-1,1-N{sub 3}){sub 2}(H{sub 2}O)]{sub 2}[Cu{sub 6}(en){sub 2}(H{sub 2}O){sub 2}(B-α-PW{sub 9}O{sub 34}){sub 2}])·6H{sub 2}O (1) (en=ethylene-diamine) has been prepared under hydrothermal conditions and structurally characterized by elemental analyses, IR spectra, powder X-ray diffraction (PXRD) and single-crystal X-ray diffraction. 1 displays a beautiful 1-D chain architecture constructed from sandwich-type [Cu{sub 2}(en){sub 2}(μ-1,1-N{sub 3}){sub 2}(H{sub 2}O)]{sub 2}[Cu{sub 6}(en){sub 2}(H{sub 2}O){sub 2}(B-α-PW{sub 9}O{sub 34}){sub 2}]{sup 2−} units and [Cu(en){sub 2}]{sup 2+} linkers. To our knowledge, 1 represents the first hexa-Cu{sup II} sandwiched phosphotungstate with supporting Cu–azido complexes. - Graphical abstract: The first hexa-Cu{sup II} sandwiched phosphotungstate with supporting Cu–azido complexes has been prepared and characterized. Display Omitted - Highlights: • Hexa-copper-substituted phosphotungstate. • Cu–azido complexes modified hexa-Cu{sup II} substituted sandwich-type polyoxometalate. • 1-D chain architecture built by hexa-copper-substituted polyoxotungstate units.

  12. Assessing the habitability of planets with Earth-like atmospheres with 1D and 3D climate modeling

    NASA Astrophysics Data System (ADS)

    Godolt, M.; Grenfell, J. L.; Kitzmann, D.; Kunze, M.; Langematz, U.; Patzer, A. B. C.; Rauer, H.; Stracke, B.

    2016-07-01

    Context. The habitable zone (HZ) describes the range of orbital distances around a star where the existence of liquid water on the surface of an Earth-like planet is in principle possible. The applicability of one-dimensional (1D) climate models for the estimation of the HZ boundaries has been questioned by recent three-dimensional (3D) climate studies. While 3D studies can calculate the water vapor, ice albedo, and cloud feedback self-consistently and therefore allow for a deeper understanding and the identification of relevant climate processes, 1D model studies rely on fewer model assumptions and can be more easily applied to the large parameter space possible for extrasolar planets. Aims: We evaluate the applicability of 1D climate models to estimate the potential habitability of Earth-like extrasolar planets by comparing our 1D model results to those of 3D climate studies in the literature. We vary the two important planetary properties, surface albedo and relative humidity, in the 1D model. These depend on climate feedbacks that are not treated self-consistently in most 1D models. Methods: We applied a cloud-free 1D radiative-convective climate model to calculate the climate of Earth-like planets around different types of main-sequence stars with varying surface albedo and relative humidity profile. We compared the results to those of 3D model calculations available in the literature and investigated to what extent the 1D model can approximate the surface temperatures calculated by the 3D models. Results: The 1D parameter study results in a large range of climates possible for an Earth-sized planet with an Earth-like atmosphere and water reservoir at a certain stellar insolation. At some stellar insolations the full spectrum of climate states could be realized, i.e., uninhabitable conditions due to surface temperatures that are too high or too low as well as habitable surface conditions, depending only on the relative humidity and surface albedo assumed. When

  13. Conversion of Human Steroid 5[beta]-Reductase (AKR1D1) into 3[beta]-Hydroxysteroid Dehydrogenase by Single Point Mutation E120H: Example of Perfect Enzyme Engineering

    SciTech Connect

    Chen, Mo; Drury, Jason E.; Christianson, David W.; Penning, Trevor M.

    2012-10-10

    Human aldo-keto reductase 1D1 (AKR1D1) and AKR1C enzymes are essential for bile acid biosynthesis and steroid hormone metabolism. AKR1D1 catalyzes the 5{beta}-reduction of {Delta}{sup 4}-3-ketosteroids, whereas AKR1C enzymes are hydroxysteroid dehydrogenases (HSDs). These enzymes share high sequence identity and catalyze 4-pro-(R)-hydride transfer from NADPH to an electrophilic carbon but differ in that one residue in the conserved AKR catalytic tetrad, His120 (AKR1D1 numbering), is substituted by a glutamate in AKR1D1. We find that the AKR1D1 E120H mutant abolishes 5{beta}-reductase activity and introduces HSD activity. However, the E120H mutant unexpectedly favors dihydrosteroids with the 5{alpha}-configuration and, unlike most of the AKR1C enzymes, shows a dominant stereochemical preference to act as a 3{beta}-HSD as opposed to a 3{alpha}-HSD. The catalytic efficiency achieved for 3{beta}-HSD activity is higher than that observed for any AKR to date. High resolution crystal structures of the E120H mutant in complex with epiandrosterone, 5{beta}-dihydrotestosterone, and {Delta}{sup 4}-androstene-3,17-dione elucidated the structural basis for this functional change. The glutamate-histidine substitution prevents a 3-ketosteroid from penetrating the active site so that hydride transfer is directed toward the C3 carbonyl group rather than the {Delta}{sup 4}-double bond and confers 3{beta}-HSD activity on the 5{beta}-reductase. Structures indicate that stereospecificity of HSD activity is achieved because the steroid flips over to present its {alpha}-face to the A-face of NADPH. This is in contrast to the AKR1C enzymes, which can invert stereochemistry when the steroid swings across the binding pocket. These studies show how a single point mutation in AKR1D1 can introduce HSD activity with unexpected configurational and stereochemical preference.

  14. Measurement-induced disturbance and thermal negativity in 1D optical lattice chain

    SciTech Connect

    Guo, Jin-Liang; Lin-Wang; Long, Gui-Lu

    2013-03-15

    We study the measurement-induced disturbance (MID) in a 1D optical lattice chain with nonlinear coupling. Special attention is paid to the difference between the thermal entanglement and MID when considering the influences of the linear coupling constant, nonlinear coupling constant and external magnetic field. It is shown that MID is more robust than thermal entanglement against temperature T and external magnetic field B, and MID may reveal more properties about quantum correlations of the system, which can be seen from the point of view that MID can be nonzero when there is no thermal entanglement and MID can detect the critical point of quantum phase transition at finite temperature. - Highlights: Black-Right-Pointing-Pointer The nonlinear coupling constant can strengthen the quantum correlation. Black-Right-Pointing-Pointer MID is more robust than entanglement against temperature and magnetic field. Black-Right-Pointing-Pointer MID exhibits more information about quantum correlation than entanglement. Black-Right-Pointing-Pointer MID can detect the critical point of quantum phase transition at finite temperature.

  15. An enriched 1D finite element for the buckling analysis of sandwich beam-columns

    NASA Astrophysics Data System (ADS)

    Sad Saoud, Kahina; Le Grognec, Philippe

    2016-06-01

    Sandwich constructions have been widely used during the last few decades in various practical applications, especially thanks to the attractive compromise between a lightweight and high mechanical properties. Nevertheless, despite the advances achieved to date, buckling still remains a major failure mode for sandwich materials which often fatally leads to collapse. Recently, one of the authors derived closed-form analytical solutions for the buckling analysis of sandwich beam-columns under compression or pure bending. These solutions are based on a specific hybrid formulation where the faces are represented by Euler-Bernoulli beams and the core layer is described as a 2D continuous medium. When considering more complex loadings or non-trivial boundary conditions, closed-form solutions are no more available and one must resort to numerical models. Instead of using a 2D computationally expensive model, the present paper aims at developing an original enriched beam finite element. It is based on the previous analytical formulation, insofar as the skin layers are modeled by Timoshenko beams whereas the displacement fields in the core layer are described by means of hyperbolic functions, in accordance with the modal displacement fields obtained analytically. By using this 1D finite element, linearized buckling analyses are performed for various loading cases, whose results are confronted to either analytical or numerical reference solutions, for validation purposes.

  16. 1D-Simulation of Thermonuclear Target Compression and Burning for Laser Facility NIF and LMJ

    NASA Astrophysics Data System (ADS)

    Valiev, R. Zh.; Chizhkov, M. N.; Karlyhanov, N. G.; Lusganova, O. V.; Lykov, V. A.; Netsvetayev, D. S.; Timakova, M. S.

    2006-08-01

    The high-power laser facilities NIF and LMJ with the pulse energy as high as 2 MJ are being created in the USA and France. The basic cryogenic indirect-drive targets for thermonuclear ignition on these facilities are a spherical shell from polystyrene doped with oxygen and bromine. (CH+5%O+0,25%Br), whose inner surface is covered with DT-ice layer. The central region of targets is filled with DT-gas. The targets for NIF and LMJ have different external radii (1,11 and 1,215 mm, correspondingly), masses of DT-fuel (210 и 310 μg), X-ray radiation temperature dependences in time. The thermonuclear yield from the NIF target calculated with LASNEX code is 15 MJ, the yield from the LMJ target calculated with FCI1 code is 25.4 MJ. In RFNC-VNIITF calculations of compression and burning of basic NIF and LMJ targets were performed by using of the 1D ERA code in the spectral diffusion approximation for radiation transfer. We used tabulated opacity calculated by the mean ion model. Thermonuclear yield calculated with ERA code is about 18 MJ for the NIF target and nearly 23 MJ for the LMJ target. Calculated yields are in good agreement with published results. Performed calculations justified the possibility to simulate ICF targets in RFNC-VNIITF. In paper are also presented analysis results of target sensitivity to opacity and X-ray temperature variations.

  17. Subpixelic measurement of large 1D displacements: principle, processing algorithms, performances and software.

    PubMed

    Guelpa, Valérian; Laurent, Guillaume J; Sandoz, Patrick; Zea, July Galeano; Clévy, Cédric

    2014-01-01

    This paper presents a visual measurement method able to sense 1D rigid body displacements with very high resolutions, large ranges and high processing rates. Sub-pixelic resolution is obtained thanks to a structured pattern placed on the target. The pattern is made of twin periodic grids with slightly different periods. The periodic frames are suited for Fourier-like phase calculations-leading to high resolution-while the period difference allows the removal of phase ambiguity and thus a high range-to-resolution ratio. The paper presents the measurement principle as well as the processing algorithms (source files are provided as supplementary materials). The theoretical and experimental performances are also discussed. The processing time is around 3 µs for a line of 780 pixels, which means that the measurement rate is mostly limited by the image acquisition frame rate. A 3-σ repeatability of 5 nm is experimentally demonstrated which has to be compared with the 168 µm measurement range. PMID:24625736

  18. A New 2D-Transport, 1D-Diffusion Approximation of the Boltzmann Transport equation

    SciTech Connect

    Larsen, Edward

    2013-06-17

    The work performed in this project consisted of the derivation, implementation, and testing of a new, computationally advantageous approximation to the 3D Boltz- mann transport equation. The solution of the Boltzmann equation is the neutron flux in nuclear reactor cores and shields, but solving this equation is difficult and costly. The new “2D/1D” approximation takes advantage of a special geometric feature of typical 3D reactors to approximate the neutron transport physics in a specific (ax- ial) direction, but not in the other two (radial) directions. The resulting equation is much less expensive to solve computationally, and its solutions are expected to be sufficiently accurate for many practical problems. In this project we formulated the new equation, discretized it using standard methods, developed a stable itera- tion scheme for solving the equation, implemented the new numerical scheme in the MPACT code, and tested the method on several realistic problems. All the hoped- for features of this new approximation were seen. For large, difficult problems, the resulting 2D/1D solution is highly accurate, and is calculated about 100 times faster than a 3D discrete ordinates simulation.

  19. Modelling hydrology of a single bioretention system with HYDRUS-1D.

    PubMed

    Meng, Yingying; Wang, Huixiao; Chen, Jiangang; Zhang, Shuhan

    2014-01-01

    A study was carried out on the effectiveness of bioretention systems to abate stormwater using computer simulation. The hydrologic performance was simulated for two bioretention cells using HYDRUS-1D, and the simulation results were verified by field data of nearly four years. Using the validated model, the optimization of design parameters of rainfall return period, filter media depth and type, and surface area was discussed. And the annual hydrologic performance of bioretention systems was further analyzed under the optimized parameters. The study reveals that bioretention systems with underdrains and impervious boundaries do have some detention capability, while their total water retention capability is extremely limited. Better detention capability is noted for smaller rainfall events, deeper filter media, and design storms with a return period smaller than 2 years, and a cost-effective filter media depth is recommended in bioretention design. Better hydrologic effectiveness is achieved with a higher hydraulic conductivity and ratio of the bioretention surface area to the catchment area, and filter media whose conductivity is between the conductivity of loamy sand and sandy loam, and a surface area of 10% of the catchment area is recommended. In the long-term simulation, both infiltration volume and evapotranspiration are critical for the total rainfall treatment in bioretention systems.

  20. Apoferritin fibers: a new template for 1D fluorescent hybrid nanostructures.

    PubMed

    Jurado, Rocío; Castello, Fabio; Bondia, Patricia; Casado, Santiago; Flors, Cristina; Cuesta, Rafael; Domínguez-Vera, José M; Orte, Angel; Gálvez, Natividad

    2016-05-01

    Recently, research in the field of protein amyloid fibers has gained great attention due to the use of these materials as nanoscale templates for the construction of functional hybrid materials. The formation of apoferritin amyloid-like protein fibers is demonstrated herein for the first time. The morphology, size and stiffness of these one-dimensional structures are comparable to the fibers formed by β-lactoglobulin, a protein frequently used as a model in the study of amyloid-like fibrillar proteins. Nanometer-sized globular apoferritin is capable of self-assembling to form 1D micrometer-sized structures after being subjected to a heating process. Depending on the experimental conditions, fibers with different morphologies and sizes are obtained. The wire-like protein structure is rich in functional groups and allows chemical functionalization with diverse quantum dots (QD), as well as with different Alexa Fluor (AF) dyes, leading to hybrid fluorescent fibers with variable emission wavelengths, from green to near infrared, depending on the QD and AFs coupled. For fibers containing the pair AF488 and AF647, efficient fluorescence energy transfer from the covalently coupled donor (AF488) to acceptor tags (AF647) takes place. Apoferritin fibers are proposed here as a new promising template for obtaining hybrid functional materials. PMID:27103107