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Sample records for 1d 2-region systems

  1. 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.

  2. Molecular Identification of Veterinary Yeast Isolates by Use of Sequence-Based Analysis of the D1/D2 Region of the Large Ribosomal Subunit▿

    PubMed Central

    Garner, Cherilyn D.; Starr, Jennifer K.; McDonough, Patrick L.; Altier, Craig

    2010-01-01

    Conventional methods of yeast identification are often time-consuming and difficult; however, recent studies of sequence-based identification methods have shown promise. Additionally, little is known about the diversity of yeasts identified from various animal species in veterinary diagnostic laboratories. Therefore, in this study, we examined three methods of identification by using 109 yeast samples isolated during a 1-year period from veterinary clinical samples. Comparison of the three methods—traditional substrate assimilation, fatty acid profile analysis, and sequence-based analysis of the region spanning the D1 and D2 regions (D1/D2) of the large ribosomal subunit—showed that sequence analysis provided the highest percent identification among the three. Sequence analysis identified 87% of isolates to the species level, whereas substrate assimilation and fatty acid profile analysis identified only 54% and 47%, respectively. Less-stringent criteria for identification increased the percentage of isolates identified to 98% for sequence analysis, 62% for substrate assimilation, and 55% for fatty acid profile analysis. We also found that sequence analysis of the internal transcribed spacer 2 (ITS2) region provided further identification for 36% of yeast not identified to the species level by D1/D2 sequence analysis. Additionally, we identified a large variety of yeast from animal sources, with at least 30 different species among the isolates tested, and with the majority not belonging to the common Candida spp., such as C. albicans, C. glabrata, C. tropicalis, and the C. parapsilosis group. Thus, we determined that sequence analysis of the D1/D2 region was the best method for identification of the variety of yeasts found in a veterinary population. PMID:20392917

  3. Molecular identification of veterinary yeast isolates by use of sequence-based analysis of the D1/D2 region of the large ribosomal subunit.

    PubMed

    Garner, Cherilyn D; Starr, Jennifer K; McDonough, Patrick L; Altier, Craig

    2010-06-01

    Conventional methods of yeast identification are often time-consuming and difficult; however, recent studies of sequence-based identification methods have shown promise. Additionally, little is known about the diversity of yeasts identified from various animal species in veterinary diagnostic laboratories. Therefore, in this study, we examined three methods of identification by using 109 yeast samples isolated during a 1-year period from veterinary clinical samples. Comparison of the three methods-traditional substrate assimilation, fatty acid profile analysis, and sequence-based analysis of the region spanning the D1 and D2 regions (D1/D2) of the large ribosomal subunit-showed that sequence analysis provided the highest percent identification among the three. Sequence analysis identified 87% of isolates to the species level, whereas substrate assimilation and fatty acid profile analysis identified only 54% and 47%, respectively. Less-stringent criteria for identification increased the percentage of isolates identified to 98% for sequence analysis, 62% for substrate assimilation, and 55% for fatty acid profile analysis. We also found that sequence analysis of the internal transcribed spacer 2 (ITS2) region provided further identification for 36% of yeast not identified to the species level by D1/D2 sequence analysis. Additionally, we identified a large variety of yeast from animal sources, with at least 30 different species among the isolates tested, and with the majority not belonging to the common Candida spp., such as C. albicans, C. glabrata, C. tropicalis, and the C. parapsilosis group. Thus, we determined that sequence analysis of the D1/D2 region was the best method for identification of the variety of yeasts found in a veterinary population.

  4. Uniform Propagation of Chaos for Kac's 1D Particle System

    NASA Astrophysics Data System (ADS)

    Cortez, Roberto

    2016-12-01

    In this paper we study Kac's 1D particle system, consisting of the velocities of N particles colliding at constant rate and randomly exchanging energies. We prove uniform (in time) propagation of chaos in Wasserstein distance with explicit polynomial rates in N, for both the squared (i.e., the energy) and non-squared particle system. These rates are of order N^{-1/3} (almost, in the non-squared case), assuming that the initial distribution of the limit nonlinear equation has finite moments of sufficiently high order (4+ɛ is enough when using the 2-Wasserstein distance). The proof relies on a convenient parametrization of the collision recently introduced by Hauray, as well as on a coupling technique developed by Cortez and Fontbona.

  5. Plasmonic Excitations of 1D Metal-Dielectric Interfaces in 2D Systems: 1D Surface Plasmon Polaritons

    NASA Astrophysics Data System (ADS)

    Mason, Daniel R.; Menabde, Sergey G.; Yu, Sunkyu; Park, Namkyoo

    2014-04-01

    Surface plasmon-polariton (SPP) excitations of metal-dielectric interfaces are a fundamental light-matter interaction which has attracted interest as a route to spatial confinement of light far beyond that offered by conventional dielectric optical devices. Conventionally, SPPs have been studied in noble-metal structures, where the SPPs are intrinsically bound to a 2D metal-dielectric interface. Meanwhile, recent advances in the growth of hybrid 2D crystals, which comprise laterally connected domains of distinct atomically thin materials, provide the first realistic platform on which a 2D metal-dielectric system with a truly 1D metal-dielectric interface can be achieved. Here we show for the first time that 1D metal-dielectric interfaces support a fundamental 1D plasmonic mode (1DSPP) which exhibits cutoff behavior that provides dramatically improved light confinement in 2D systems. The 1DSPP constitutes a new basic category of plasmon as the missing 1D member of the plasmon family: 3D bulk plasmon, 2DSPP, 1DSPP, and 0D localized SP.

  6. Differentiation of Candida glabrata, C. nivariensis and C. bracarensis based on fragment length polymorphism of ITS1 and ITS2 and restriction fragment length polymorphism of ITS and D1/D2 regions in rDNA.

    PubMed

    Mirhendi, H; Bruun, B; Schønheyder, H C; Christensen, J J; Fuursted, K; Gahrn-Hansen, B; Johansen, H K; Nielsen, L; Knudsen, J D; Arendrup, M C

    2011-11-01

    Different molecular methods for the discrimination of Candida glabrata, C. bracarensis and C. nivariensis were evaluated and the prevalence of these species among Danish blood isolates investigated. Control strains were used to determine fragment length polymorphism in the ITS1, ITS2, ITS1-5.8S-ITS2 regions and in the D1/D2 domain of 26S rDNA using primers designed for this study. A total of 133 blood isolates previously identified as C. glabrata were examined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and the peptide nucleic acid-fluorescent in situ hybridization (PNA-FISH) method. The size of ITS1 allowed differentiation between C. glabrata (483), C. nivariensis (361) and C. bracarensis (385), whereas the ITS2 region was of similar size in C. nivariensis (417) and C. glabrata (418). Sequence analysis of the ITS region suggested that many restriction enzymes were suitable for RFLP differentiation of the species. Enzymatic digestion of the D1/D2 domain with TatI produced unique band sizes for each of the three species. PCR-RFLP and PNA-FISH were in agreement for all of the isolates tested. None of the 133 Danish blood isolates were C. nivariensis or C. bracarensis. Fragment size polymorphism of ITS1 and RFLP of the D1/D2 domain or the ITS region are useful methods for the differentiation of the species within the C. glabrata group. C. bracarensis and C. nivariensis are rare among Danish C. glabrata blood isolates.

  7. Multiple-state quantum Otto engine, 1D box system

    NASA Astrophysics Data System (ADS)

    Latifah, E.; Purwanto, A.

    2014-03-01

    Quantum heat engines produce work using quantum matter as their working substance. We studied adiabatic and isochoric processes and defined the general force according to quantum system. The processes and general force are used to evaluate a quantum Otto engine based on multiple-state of one dimensional box system and calculate the efficiency. As a result, the efficiency depends on the ratio of initial and final width of system under adiabatic processes.

  8. Multiple-state quantum Otto engine, 1D box system

    SciTech Connect

    Latifah, E.; Purwanto, A.

    2014-03-24

    Quantum heat engines produce work using quantum matter as their working substance. We studied adiabatic and isochoric processes and defined the general force according to quantum system. The processes and general force are used to evaluate a quantum Otto engine based on multiple-state of one dimensional box system and calculate the efficiency. As a result, the efficiency depends on the ratio of initial and final width of system under adiabatic processes.

  9. Search and tracking system architecture using 1-D scanning sensors

    NASA Astrophysics Data System (ADS)

    Nam, Sanghoon; Choi, Byungin; Joung, Shichang; Kim, Jaein

    2010-04-01

    In the maritime environment, It is necessary for ship's self protection to search ad track approaching targets. We developed high performance search and tracking system with Infrared sensors. Our system can obtain high performance with several FPGAs and COTS processing boards. Dual band IR sensor (MWIR and LWIR) also gives two types of target detection and tracing abilities. Our system designed to automatically detect and track both air and surface targets such as sea skimming missiles, small ships, and aircrafts at a long range. In this paper, we describe technologies in our search and tracking system architecture. We describe software architecture for signal processing and target detection and tracking algorithms as well.

  10. Partical Simulation of Bounded 1D Plasma Systems

    NASA Astrophysics Data System (ADS)

    Lawson, William S.

    1989-02-01

    The physical and numerical problems of kinetic simulation of a bounded electrostatic plasma system in one planar dimension are examined, and solutions to them are presented. These problems include particle absorption, reflection and emission at boundaries, the solution of Poisson's equation under non-periodic boundary conditions, and the treatment of an external circuit connecting the boundaries. The methods which are described here are immlemented in a code named PDW1, which is available from Professor C. K. Birdsall, Plasma Theory and Simulation Group, Cory Hall, University of California, Berkeley, CA 94720.

  11. NATRAN2. Fluid Hammer Analysis 1D & 2D Systems

    SciTech Connect

    Shin, Y.W.; Valentin, R.A.

    1992-03-03

    NATRAN2 analyzes short-term pressure-pulse transients in a closed hydraulic system consisting of a two-dimensional axisymmetric domain connected to a one-dimensional piping network. The one-dimensional network may consist of series or parallel piping, pipe junctions, diameter discontinuities, junctions of three to six branches, closed ends, surge tanks, far ends, dummy junctions, acoustic impedance discontinuities, and rupture disks. By default, the working fluid is assumed to be liquid sodium without cavitation; but another working fluid can be specified in terms of its density, sonic speed, and viscosity. The source pressure pulse can arise from one of the following: a pressure-time function specified at some point in the two-dimensional domain, a pressure-time function or a sodium-water reaction specified at some point in the one-dimensional domain. The pressure pulse from a sodium-water reaction is assumed to be generated according to the dynamic model of Zaker and Salmon.

  12. Magnetic properties driven by local structure in quasi-1D Ising chain system cobaltate system

    NASA Astrophysics Data System (ADS)

    Kim, Bongjae; Kim, Beom Hyun; Kim, Kyoo; Choi, Hong Chul; Park, Sang-Yeon; Jeong, Y.-H.; Min, B. I.

    2012-02-01

    Using ab-initio band structure method and the microscopic model calculation, the origins of the large orbital magnetic moment and unique magnetic anisotropy in the quasi-1D magnetic cobaltate, α-CoV2O6, is investigated. Unique crystal electric field effect in α-CoV2O6 is combined with the strong spin-orbit coupling, results in intriguing magnetic properties of the system. Based on the estimated strengths of the intra- and the inter-chain exchange interaction, experimentally found 1/3 magnetization plateau in the MH curve can be attributed to spin-flop mechanism. Origin of the reduced magnetic entropy behavior is found to be the strong uniaxial magnetic anisotropy in the quasi-1D Ising chain system.

  13. 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.

  14. 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.

  15. Microstates of the D1-D5-Kaluza-Klein monopole system

    SciTech Connect

    Bena, Iosif; Kraus, Per

    2005-07-15

    We find supergravity solutions corresponding to all U(1)xU(1) invariant chiral primaries of the D1-D5-KK system. These solutions are 1/8 BPS, carry angular momentum, and are asymptotically flat in the 3+1 dimensional sense. They can be thought of as representing the ground states of the four-dimensional black hole constructed from the D1-D5-KK-P system. Demanding the absence of unphysical singularities in our solutions determines all free parameters, and gives precise agreement with the quantum numbers expected from the CFT point of view. The physical mechanism behind the smoothness of the solutions is that the D1 branes and D5 branes expand into a KK-monopole supertube in the transverse space of the original KK monopole.

  16. 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

  17. Potential energy surface intersections in the C(1D)H2 reactive system.

    PubMed

    Liu, Xiaojun; Bian, Wensheng; Zhao, Xian; Tao, Xutang

    2006-08-21

    Potential energy surface (PES) intersection seams of two or more electronic states from the 1 1A', 2 1A', 3 1A', 1 1A", and 2 1A" states in the C(1D)H2 reactive system are investigated using the internally contracted multireference configuration interaction method and the aug-cc-pVQZ basis set. Intersection seams with energies less than 20 kcal/mol relative to the C(1D) + H2 asymptote are searched systematically, and finally several seam lines (at the linear H-C-H, linear C-H-H, and C(2v), geometries, respectively) and a seam surface (at Cs geometries) are discovered and determined. The minimum energy crossing points on these seams are reported and the influences of the PES intersections, in particular, conical intersections, on the CH2 spectroscopy and the C(1D) + H2 reaction dynamics are discussed. In addition, geometries and energies of the 1 1A2 and 1 1B2 states of methylene biradical CH2 are reported in detail for the first time.

  18. 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

  19. Development and tests of x-ray multifoil optical system for 1D imaging (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Pína, Ladislav; Hudec, René; Inneman, Adolf J.; Baca, Tomas; Blazek, M.; Platkevic, M.; Sieger, Ladislav; Doubravova, Daniela; McEntaffer, Randall L.; Schultz, Ted B.; Dániel, Vladimír.

    2016-09-01

    The proposed wide-field optical system has not been used yet. Described novel approach is based on the use of 1D "Lobster eye" optics in combination with Timepix X-ray detector in the energy range 3 - 40 keV. The proposed project includes theoretical study and a functional sample of the Timepix X-ray detector with multifoil wide-field X-ray "Lobster eye" optics. Using optics to focus X-rays on a detector is necessary in cases where the intensity of impinging X-ray radiation is below the sensitivity of the detector without optic. Generally this is the case of very low light phenomena, or e.g. monitoring astrophysical objects in space. Namely, such optical system could find applications in laboratory spectroscopy systems or in a rocket space experiment. Designed wide-field optical system combined with Timepix X-ray detector is described together with experimental results obtained during laboratory tests.

  20. Modelling Hydrology of a Single Bioretention System with HYDRUS-1D

    PubMed Central

    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. PMID:25133240

  1. 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.

  2. Nonconstant Positive Steady States and Pattern Formation of 1D Prey-Taxis Systems

    NASA Astrophysics Data System (ADS)

    Wang, Qi; Song, Yang; Shao, Lingjie

    2016-08-01

    Prey-taxis is the process that predators move preferentially toward patches with highest density of prey. It is well known to have an important role in biological control and the maintenance of biodiversity. To model the coexistence and spatial distributions of predator and prey species, this paper concerns nonconstant positive steady states of a wide class of prey-taxis systems with general functional responses over 1D domain. Linearized stability of the positive equilibrium is analyzed to show that prey-taxis destabilizes prey-predator homogeneity when prey repulsion (e.g., due to volume-filling effect in predator species or group defense in prey species) is present, and prey-taxis stabilizes the homogeneity otherwise. Then, we investigate the existence and stability of nonconstant positive steady states to the system through rigorous bifurcation analysis. Moreover, we provide detailed and thorough calculations to determine properties such as pitchfork and turning direction of the local branches. Our stability results also provide a stable wave mode selection mechanism for thee reaction-advection-diffusion systems including prey-taxis models considered in this paper. Finally, we provide numerical studies of prey-taxis systems with Holling-Tanner kinetics to illustrate and support our theoretical findings. Our numerical simulations demonstrate that the 2× 2 prey-taxis system is able to model the formation and evolution of various striking patterns, such as spikes, periodic oscillations, and coarsening even when the domain is one-dimensional. These dynamics can model the coexistence and spatial distributions of interacting prey and predator species. We also give some insights on how system parameters influence pattern formation in these models.

  3. Nonconstant Positive Steady States and Pattern Formation of 1D Prey-Taxis Systems

    NASA Astrophysics Data System (ADS)

    Wang, Qi; Song, Yang; Shao, Lingjie

    2017-02-01

    Prey-taxis is the process that predators move preferentially toward patches with highest density of prey. It is well known to have an important role in biological control and the maintenance of biodiversity. To model the coexistence and spatial distributions of predator and prey species, this paper concerns nonconstant positive steady states of a wide class of prey-taxis systems with general functional responses over 1D domain. Linearized stability of the positive equilibrium is analyzed to show that prey-taxis destabilizes prey-predator homogeneity when prey repulsion (e.g., due to volume-filling effect in predator species or group defense in prey species) is present, and prey-taxis stabilizes the homogeneity otherwise. Then, we investigate the existence and stability of nonconstant positive steady states to the system through rigorous bifurcation analysis. Moreover, we provide detailed and thorough calculations to determine properties such as pitchfork and turning direction of the local branches. Our stability results also provide a stable wave mode selection mechanism for thee reaction-advection-diffusion systems including prey-taxis models considered in this paper. Finally, we provide numerical studies of prey-taxis systems with Holling-Tanner kinetics to illustrate and support our theoretical findings. Our numerical simulations demonstrate that the 2× 2 prey-taxis system is able to model the formation and evolution of various striking patterns, such as spikes, periodic oscillations, and coarsening even when the domain is one-dimensional. These dynamics can model the coexistence and spatial distributions of interacting prey and predator species. We also give some insights on how system parameters influence pattern formation in these models.

  4. 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.

  5. Regional emissions data base and evaluation system (REDES): Volume 2, Regional emissions evaluation data base (REED)

    SciTech Connect

    Boyd, G.A.; Campbell, A.P.; Davis, M.J.; Veselka, T.D.

    1988-08-01

    A three-volume report has been prepared to document these REDES data bases and computer model. This volume documents the data base for forecasting emissions. This disaggregated forecast data base of energy use and emissions for electric utility and industrial boilers for 1985 through 2010 is called REED (Regional Emissions Evaluation Data Base). The other volumes describe the methodology of the evaluation system and user-driven menu system (Vol. 1) and document the data base that characterizes 21 generic technologies (Vol. 3). All three volumes provide the user with a complete description of REDES, which is designed to forecast the change in emissions that could result from using a particular clean coal technology. The US Department of Energy's Innovative Clean Coal Technology (ICCT) program has solicited proposals from the private sector to demonstrate innovative technologies that allow the clean use of coal as an energy source. The US Department of Energy and the ICCT Source Evaluation Board requested that Argonne National Laboratory develop two data bases and a personal-computer-based model to aid in evaluating the potential for these proposed technologies to reduce environmental residuals. Version 1.0 of the Regional Emissions Data Base and Evaluation System (REDES) is available to the public through the National Energy Software Center. 41 refs., 16 tabs.

  6. 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.

  7. National Geothermal Data System Hub Deployment Timeline (Appendix E-1-d)

    SciTech Connect

    Caudill, Christy

    2015-12-20

    Excel spreadsheet describing activity, spending, and development for the four data hubs (Arizona Geoloical Survey, Kentucky Geological Survey, Illinois Geological Survey, and Nevada Bureau of Mines and Geology) serving data for the National Geothermal Data System under the State Contributions to the National Geothermal Data System Project.

  8. Extensional Elastica in large deformation as $Gamma $ Γ -limit of a discrete 1D mechanical system

    NASA Astrophysics Data System (ADS)

    Alibert, Jean-Jacques; Della Corte, Alessandro; Giorgio, Ivan; Battista, Antonio

    2017-04-01

    The present paper deals with the rigorous homogenization of a discrete system consisting of extensible rods linked by rotational springs. Specifically, a Γ -convergence result is proven for a sequence of discrete measure functionals En, describing the energy of the discrete system, toward the continuous energy functional for the extensible Euler beam model ( Elastica) in large deformation regime. A relative compactness result for the sequence En is also proven. Moreover, numerical results are shown on the deformed shape and on the total energy of the system when the number of elements of the discrete system increases. The numerical convergence of the energy to a definite value is shown in two cases. The results provide rigorous justification of a very commonly used algorithm for the discretization of the extensible Euler beam, namely Hencky-type beam model.

  9. New way to produce dense double-antikaonic dibaryon system, &#x1D43E;̄&#x1D43E;̄NN, through Λ(1405)-doorway sticking in p + p collisions

    PubMed Central

    YAMAZAKI, Toshimitsu; AKAISHI, Yoshinori; HASSANVAND, Maryam

    2011-01-01

    A recent successful observation of a dense and deeply bound &#x1D43E;̄ nuclear system, K−pp, in the p + p → K+ + K−pp reaction in a DISTO experiment indicates that the double-&#x1D43E;̄ dibaryon, K−K−pp, which was predicted to be a dense nuclear system, can also be formed in p + p collisions. We find theoretically that the K−-K− repulsion plays no significant role in reducing the density and binding energy of K−K−pp and that, when two Λ(1405) resonances are produced simultaneously in a short-range p + p collision, they act as doorways to copious formation of K−K−pp, if and only if K−K−pp is a dense object, as predicted. PMID:21670568

  10. Read-out optical schemes for holographic memory system based on multiplexed computer generated 1D Fourier holograms

    NASA Astrophysics Data System (ADS)

    Donchenko, Sergey S.; Odinokov, Sergey B.; Bobrinev, Vladimir I.; Betin, Alexandr Y.; Zlokazov, Evgenie Y.

    2015-05-01

    Computer holographic synthesis allows to significantly simplify the recording scheme of microholograms in holographic memory system as the classic high precision holographic setup based on two-beam interference is removed by simple scale reduction projection scheme. Application of computer generated 1D-Fourier holograms provides the possibility of selective reconstruction of the multiplexed holograms with different orientation of data lines by corresponding rotation of anamorphic objective (cylindrical lens), used in the read-out systems. Two configurations of read-out optical scheme were investigated by our team: full-page scheme and line-by-line scheme. In the present article we report the specificities of these schemes and consider their advantages and disadvantages. The results of experimental modeling of both read-out configurations are also presented.

  11. A pulsed THz imaging system with a line focus and a balanced 1-D detection scheme with two industrial CCD line-scan cameras.

    PubMed

    Wiegand, Christian; Herrmann, Michael; Bachtler, Sebastian; Klier, Jens; Molter, Daniel; Jonuscheit, Joachim; Beigang, René

    2010-03-15

    We present a pulsed THz Imaging System with a line focus intended to speed up measurements. A balanced 1-D detection scheme working with two industrial line-scan cameras is used. The instrument is implemented without the need for an amplified laser system, increasing the industrial applicability. The instrumental characteristics are determined.

  12. Longevity of duct tape in residential air distribution systems: 1-D, 2-D, and 3-D joints

    SciTech Connect

    Abushakra, Bass

    2002-05-30

    The aging tests conducted so far showed that duct tape tends to degrade in its performance as the joint it is applied to requires a geometrical description of a higher number of space dimensions (1-D, 2-D, 3-D). One-dimensional joints are the easiest to seal with duct tape, and thus the least to experience failure. Two-dimensional joints, such as the flexible duct core-to-collar joints tested in this study, are less likely to fail than three-dimensional collar-to-plenum joints, as the shrinkage could have a positive effect in tightening the joint. Three-dimensional joints are the toughest to seal and the most likely to experience failure. The 2-D flexible duct core-to-collar joints passed the six-month period of the aging test in terms of leakage, but with the exception of the foil-butyl tape, showed degradation in terms hardening, brittleness, partial peeling, shrinkage, wrinkling, delamination of the tape layers, flaking, cracking, bubbling, oozing and discoloration. The baking test results showed that the failure in the duct tape joints could be attributed to the type of combination of the duct tape and the material it is applied to, as the duct tape behaves differently with different substrates. Overall, the foil-butyl tape (Tape 4) had the best results, while the film tape (Tape 3) showed the most deterioration. The conventional duct tapes tested (Tape 1 and Tape 2) were between these two extremes, with Tape 2 performing better than Tape 1. Lastly, we found that plastic straps became discolored and brittle during the tests, and a couple of straps broke completely. Therefore, we recommend that clamping the duct-taped flexible core-to-collar joints should be done with metallic adjustable straps.

  13. Controlling a class of chaotic quantum system under disturbances and noisy measurements: Application to 1D Bose-Einstein condensate

    NASA Astrophysics Data System (ADS)

    Aguilar-López, Ricardo; López-Pérez, Pablo A.; Lara-Cisneros, Gerardo; Femat, Ricardo

    2016-09-01

    In this paper, a robust nonlinear feedback control scheme with adaptive gain is proposed to control the chaotic behavior in a Bose-Einstein condensate (BEC). The control goal concerns the track or regulation purposes. The BEC system is represented as stochastic ordinary differential equations with measured output perturbed by Gaussian noise, which represents the nature of the quantum systems. The convergence of the BEC control law is analyzed under the frame of the Lyapunov stability theory. Numerical experiments show an adequate performance of the proposed methodology under the required conditions. The results are applicable when the shape of the condensate is sufficiently simple.

  14. Symmetry Violations in Partially Oxidized One-Dimensional (1D) Transition Metal Polymers. Metal-Ligand-Metal (M-L-M) Bridged Systems

    NASA Astrophysics Data System (ADS)

    Böhm, Michael C.

    1984-09-01

    The band structure of the metal-ligand-metal (M-L-M) bridged quasi one-dimensional (1D) cyclopentadienylmanganese polymer, MnCp 1, has been studied in the unoxidized state and in a partly oxidized modification with one electron removed from each second MnCp fragment. The tight-binding approach is based on a semiempirical self-consistent-field (SCF) Hartree-Fock (HF) crystal orbital (CO) model of the INDO-type (intermediate neglect of differential overlap) combined with a statistical averaging procedure which has its origin in the grand canonical ensemble. The latter approximation allows for an efficient investigation of violations of the translation symmetries in the oxidized 1D material. The oxidation process in 1 is both ligand- and metal-centered (Mn 3d-2 states). The mean-field minimum corresponds to a charge density wave (CDW) solution with inequivalent Mn sites within the employed repeat-units. The symmetry adapted solution with electronically identical 3d centers is a maximum in the variational space. The coupling of this electronic instability to geometrical deformations is also analyzed. The ligand amplitudes encountered in the hole-state wave function prevent extremely large charge separations between the 3d centers which are found in ID systems without bridging moieties (e.g. Ni(CN)2-5 chain). The symmetry reduction in oxidized 1 is compared with violations of spatial symmetries in finite transition metal derivatives and simple solids. The stabilization of the valence bond-type (VB) solution is physically rationalized (i.e. left-right correlations between the 3d centers). The computational results derived for 1 are generalized to oxidized transition metal chains with band occupancies that are simple fractions of the number of stacking units and to 1D systems that deviate from this relation. The entropy-influence for temperatures T ≠ 0 is shortly discussed (stabilization of domain or cluster structures).

  15. Simulation of decay heat removal by natural convection in a pool type fast reactor model-ramona-with coupled 1D/2D thermal hydraulic code system

    SciTech Connect

    Kasinathan, N.; Rajakumar, A.; Vaidyanathan, G.; Chetal, S.C.

    1995-09-01

    Post shutdown decay heat removal is an important safety requirement in any nuclear system. In order to improve the reliability of this function, Liquid metal (sodium) cooled fast breeder reactors (LMFBR) are equipped with redundant hot pool dipped immersion coolers connected to natural draught air cooled heat exchangers through intermediate sodium circuits. During decay heat removal, flow through the core, immersion cooler primary side and in the intermediate sodium circuits are also through natural convection. In order to establish the viability and validate computer codes used in making predictions, a 1:20 scale experimental model called RAMONA with water as coolant has been built and experimental simulation of decay heat removal situation has been performed at KfK Karlsruhe. Results of two such experiments have been compiled and published as benchmarks. This paper brings out the results of the numerical simulation of one of the benchmark case through a 1D/2D coupled code system, DHDYN-1D/THYC-2D and the salient features of the comparisons. Brief description of the formulations of the codes are also included.

  16. Calibration of a 1D/1D urban flood model using 1D/2D model results in the absence of field data.

    PubMed

    Leandro, J; Djordjević, S; Chen, A S; Savić, D A; Stanić, M

    2011-01-01

    Recently increased flood events have been prompting researchers to improve existing coupled flood-models such as one-dimensional (1D)/1D and 1D/two-dimensional (2D) models. While 1D/1D models simulate sewer and surface networks using a one-dimensional approach, 1D/2D models represent the surface network by a two-dimensional surface grid. However their application raises two issues to urban flood modellers: (1) stormwater systems planning/emergency or risk analysis demands for fast models, and the 1D/2D computational time is prohibitive, (2) and the recognized lack of field data (e.g. Hunter et al. (2008)) causes difficulties for the calibration/validation of 1D/1D models. In this paper we propose to overcome these issues by calibrating a 1D/1D model with the results of a 1D/2D model. The flood-inundation results show that: (1) 1D/2D results can be used to calibrate faster 1D/1D models, (2) the 1D/1D model is able to map the 1D/2D flood maximum extent well, and the flooding limits satisfactorily in each time-step, (3) the 1D/1D model major differences are the instantaneous flow propagation and overestimation of the flood-depths within surface-ponds, (4) the agreement in the volume surcharged by both models is a necessary condition for the 1D surface-network validation and (5) the agreement of the manholes discharge shapes measures the fitness of the calibrated 1D surface-network.

  17. Coastal fog prediction with a coupled model (1D+3D) system using the data from a 300 m met tower as input

    NASA Astrophysics Data System (ADS)

    Kim, W.; Yum, S. S.

    2015-12-01

    Visibility degradation due to fog can be very hazardous both to ground transportation and aviation traffic. However, prediction of fog using numerical models is difficult because fog formation is usually determined by local meteorological conditions that are hard to be measured and modeled with sufficient resolution. For this reason, there have been several attempts to build a coupled system of a fine resolution 1D model and a 3D mesoscale model with a usual grid resolution. In this study we uses the coupled system of the 1D PAFOG model and the 3D WRF model to simulate fogs formed at a southern coastal region of Korea, where the National Center for Intensive Observation of Severe Weather (NCIO) is located. Unique to NCIO is that it has a 300 m meteorological tower on which some basic meteorological variables (temperature, dew point temperature and winds) are measured at eleven different altitudes. In addition comprehensive cloud physics measurements are made with various remote sensing instruments such as cloud radar, wind profiler, microwave radiometer, micro rain radar. Several fog cases are identified during 2015 and will be simulated by the coupled system. The comprehensive set of measurement data from NCIO will be utilized as input to the model system and for evaluating the results. Particularly the data for initial and boundary conditions, which are tightly connected to the coupled model predictability, are extracted from the tower measurement. Furthermore, various sensitivity experiments will be done to enhance our understanding of the coastal fog formation mechanism. Detailed results will be discussed at the conference.

  18. Development of a Numerical Method for Patient-Specific Cerebral Circulation Using 1D-0D Simulation of the Entire Cardiovascular System with SPECT Data.

    PubMed

    Zhang, Hao; Fujiwara, Naoya; Kobayashi, Masaharu; Yamada, Shigeki; Liang, Fuyou; Takagi, Shu; Oshima, Marie

    2016-08-01

    The detailed flow information in the circle of Willis (CoW) can facilitate a better understanding of disease progression, and provide useful references for disease treatment. We have been developing a one-dimensional-zero-dimensional (1D-0D) simulation method for the entire cardiovascular system to obtain hemodynamics information in the CoW. This paper presents a new method for applying 1D-0D simulation to an individual patient using patient-specific data. The key issue is how to adjust the deviation of physiological parameters, such as peripheral resistance, from literature data when patient-specific geometry is used. In order to overcome this problem, we utilized flow information from single photon emission computed tomography (SPECT) data. A numerical method was developed to optimize physiological parameters by adjusting peripheral cerebral resistance to minimize the difference between the resulting flow rate and the SPECT data in the efferent arteries of the CoW. The method was applied to three cases using different sets of patient-specific data in order to investigate the hemodynamics of the CoW. The resulting flow rates in the afferent arteries were compared to those of the phase-contrast magnetic resonance angiography (PC-MRA) data. Utilization of the SPECT data combined with the PC-MRA data showed a good agreement in flow rates in the afferent arteries of the CoW with those of PC-MRA data for all three cases. The results also demonstrated that application of SPECT data alone could provide the information on the ratios of flow distributions among arteries in the CoW.

  19. Evaluation of the ocean technology system's MK 1-S wireless surface unit, MK 1 DCI two diver air radio, MK 1-D-A wireless diver unit, MK 1-D-H hardwire diver unit and MK 1-D/S unit

    NASA Astrophysics Data System (ADS)

    Reyle, B. E.

    1985-05-01

    The OTS was evaluated for intelligibility, reliability and human engineering. The test subjects possessed various levels of experience with wireless or hardwire communication and SCUBA. The conditions under which the equipment was tested varied. Surface air temperatures ranged from 37 to 85 F; water temperatures from 65 to 80 F; and water depths from 8 feet of seawater (FSW) to greater than 60 FSW. The tests were conducted inside a circular 30 foot deep ascent tower, in shallow open bay water, and finally in an open ocean environment. The equipment was evaluated in areas of both high and low noise levels on the surface as well as in water. The OTS produced an overall intelligibility of 89.24% during manned open water testing using the Modified Rhyme Test (MRT) as the evaluation criteria, with a minimum effective range of 330 yards at 12 FSW and at least 875 yards, although it appears that the range of the MK 1-D-A is somewhat greater. Human engineering aspects of the OTS were found to be more than satisfactory, with no material failures encountered during testing. It is interesting to note that whenever the equipment required minor adjustments, these could be effected by the diver in the water (on the surface) and in most cases in less than 5 minutes. The amount of maintenance required on the OTS was minimal.

  20. Helical Floquet Channels in 1D Lattices

    NASA Astrophysics Data System (ADS)

    Budich, Jan Carl; Hu, Ying; Zoller, Peter

    2017-03-01

    We show how dispersionless channels exhibiting perfect spin-momentum locking can arise in a 1D lattice model. While such spectra are forbidden by fermion doubling in static 1D systems, here we demonstrate their appearance in the stroboscopic dynamics of a periodically driven system. Remarkably, this phenomenon does not rely on any adiabatic assumptions, in contrast to the well known Thouless pump and related models of adiabatic spin pumps. The proposed setup is shown to be experimentally feasible with state-of-the-art techniques used to control ultracold alkaline earth atoms in optical lattices.

  1. 1D Thermal-Hydraulic-Chemical (THC) Reactive transport modeling for deep geothermal systems: A case study of Groß Schönebeck reservoir, Germany

    NASA Astrophysics Data System (ADS)

    Driba, D. L.; De Lucia, M.; Peiffer, S.

    2014-12-01

    Fluid-rock interactions in geothermal reservoirs are driven by the state of disequilibrium that persists among solid and solutes due to changing temperature and pressure. During operation of enhanced geothermal systems, injection of cooled water back into the reservoir disturbs the initial thermodynamic equilibrium between the reservoir and its geothermal fluid, which may induce modifications in permeability through changes in porosity and pore space geometry, consequently bringing about several impairments to the overall system.Modeling of fluid-rock interactions induced by injection of cold brine into Groß Schönebeck geothermal reservoir system situated in the Rotliegend sandstone at 4200m depth have been done by coupling geochemical modeling Code Phreeqc with OpenGeoSys. Through batch modeling the re-evaluation of the measured hydrochemical composition of the brine has been done using Quintessa databases, the results from the calculation indicate that a mineral phases comprising of K-feldspar, hematite, Barite, Calcite and Dolomite was found to match the hypothesis of equilibrium with the formation fluid, Reducing conditions are presumed in the model (pe = -3.5) in order to match the amount of observed dissolved Fe and thus considered as initial state for the reactive transport modeling. based on a measured composition of formation fluids and the predominant mineralogical assemblage of the host rock, a preliminary 1D Reactive transport modeling (RTM) was run with total time set to 30 years; results obtained for the initial simulation revealed that during this period, no significant change is evident for K-feldspar. Furthermore, the precipitation of calcite along the flow path in the brine results in a drop of pH from 6.2 to a value of 5.2 noticed over the simulated period. The circulation of cooled fluid in the reservoir is predicted to affect the temperature of the reservoir within the first 100 -150m from the injection well. Examination of porosity change in

  2. Hermite WENO limiting for multi-moment finite-volume methods using the ADER-DT time discretization for 1-D systems of conservation laws

    DOE PAGES

    Norman, Matthew R.

    2014-11-24

    New Hermite Weighted Essentially Non-Oscillatory (HWENO) interpolants are developed and investigated within the Multi-Moment Finite-Volume (MMFV) formulation using the ADER-DT time discretization. Whereas traditional WENO methods interpolate pointwise, function-based WENO methods explicitly form a non-oscillatory, high-order polynomial over the cell in question. This study chooses a function-based approach and details how fast convergence to optimal weights for smooth flow is ensured. Methods of sixth-, eighth-, and tenth-order accuracy are developed. We compare these against traditional single-moment WENO methods of fifth-, seventh-, ninth-, and eleventh-order accuracy to compare against more familiar methods from literature. The new HWENO methods improve upon existingmore » HWENO methods (1) by giving a better resolution of unreinforced contact discontinuities and (2) by only needing a single HWENO polynomial to update both the cell mean value and cell mean derivative. Test cases to validate and assess these methods include 1-D linear transport, the 1-D inviscid Burger's equation, and the 1-D inviscid Euler equations. Smooth and non-smooth flows are used for evaluation. These HWENO methods performed better than comparable literature-standard WENO methods for all regimes of discontinuity and smoothness in all tests herein. They exhibit improved optimal accuracy due to the use of derivatives, and they collapse to solutions similar to typical WENO methods when limiting is required. The study concludes that the new HWENO methods are robust and effective when used in the ADER-DT MMFV framework. Finally, these results are intended to demonstrate capability rather than exhaust all possible implementations.« less

  3. Hermite WENO limiting for multi-moment finite-volume methods using the ADER-DT time discretization for 1-D systems of conservation laws

    SciTech Connect

    Norman, Matthew R.

    2014-11-24

    New Hermite Weighted Essentially Non-Oscillatory (HWENO) interpolants are developed and investigated within the Multi-Moment Finite-Volume (MMFV) formulation using the ADER-DT time discretization. Whereas traditional WENO methods interpolate pointwise, function-based WENO methods explicitly form a non-oscillatory, high-order polynomial over the cell in question. This study chooses a function-based approach and details how fast convergence to optimal weights for smooth flow is ensured. Methods of sixth-, eighth-, and tenth-order accuracy are developed. We compare these against traditional single-moment WENO methods of fifth-, seventh-, ninth-, and eleventh-order accuracy to compare against more familiar methods from literature. The new HWENO methods improve upon existing HWENO methods (1) by giving a better resolution of unreinforced contact discontinuities and (2) by only needing a single HWENO polynomial to update both the cell mean value and cell mean derivative. Test cases to validate and assess these methods include 1-D linear transport, the 1-D inviscid Burger's equation, and the 1-D inviscid Euler equations. Smooth and non-smooth flows are used for evaluation. These HWENO methods performed better than comparable literature-standard WENO methods for all regimes of discontinuity and smoothness in all tests herein. They exhibit improved optimal accuracy due to the use of derivatives, and they collapse to solutions similar to typical WENO methods when limiting is required. The study concludes that the new HWENO methods are robust and effective when used in the ADER-DT MMFV framework. Finally, these results are intended to demonstrate capability rather than exhaust all possible implementations.

  4. Hermite WENO limiting for multi-moment finite-volume methods using the ADER-DT time discretization for 1-D systems of conservation laws

    NASA Astrophysics Data System (ADS)

    Norman, Matthew R.

    2015-02-01

    New Hermite Weighted Essentially Non-Oscillatory (HWENO) interpolants are developed and investigated within the Multi-Moment Finite-Volume (MMFV) formulation using the ADER-DT time discretization. Whereas traditional WENO methods interpolate pointwise, function-based WENO methods explicitly form a non-oscillatory, high-order polynomial over the cell in question. This study chooses a function-based approach and details how fast convergence to optimal weights for smooth flow is ensured. Methods of sixth-, eighth-, and tenth-order accuracy are developed. These are compared against traditional single-moment WENO methods of fifth-, seventh-, ninth-, and eleventh-order accuracy to compare against more familiar methods from literature. The new HWENO methods improve upon existing HWENO methods (1) by giving a better resolution of unreinforced contact discontinuities and (2) by only needing a single HWENO polynomial to update both the cell mean value and cell mean derivative. Test cases to validate and assess these methods include 1-D linear transport, the 1-D inviscid Burger's equation, and the 1-D inviscid Euler equations. Smooth and non-smooth flows are used for evaluation. These HWENO methods performed better than comparable literature-standard WENO methods for all regimes of discontinuity and smoothness in all tests herein. They exhibit improved optimal accuracy due to the use of derivatives, and they collapse to solutions similar to typical WENO methods when limiting is required. The study concludes that the new HWENO methods are robust and effective when used in the ADER-DT MMFV framework. These results are intended to demonstrate capability rather than exhaust all possible implementations.

  5. Systemic transplantation of human umbilical cord derived mesenchymal stem cells-educated T regulatory cells improved the impaired cognition in AβPPswe/PS1dE9 transgenic mice.

    PubMed

    Yang, Hongna; Yang, Hui; Xie, Zhaohong; Wei, Lifei; Bi, Jianzhong

    2013-01-01

    Alzheimer's disease (AD) is one of most prevalent dementias, which is characterized by the deposition of extracellular amyloid-beta protein (Aβ) and the formation of neurofibrillary tangles within neurons. Although stereotaxic transplantation of mesenchymal stem cells (MSCs) into the hippocampus of AD animal model as immunomodulatory cells has been suggested as a potential therapeutic approach to prevent the progress of AD, it is invasive and difficult for clinical perform. Systemic and central nervous system inflammation play an important role in pathogenesis of AD. T regulatory cells (Tregs) play a crucial role in maintaining systemic immune homeostasis, indicating that transplantation of Tregs could prevent the progress of the inflammation. In this study, we aimed to evaluate whether systemic transplantation of purified autologous Tregs from spleens of AβPPswe/PS1dE9 double-transgenic mice after MSCs from human umbilical cords (UC-MSCs) education in vitro for 3 days could improve the neuropathology and cognition deficits in AβPPswe/PS1dE9 double-transgenic mice. We observed that systemic transplantation of autologous Tregs significantly ameliorate the impaired cognition and reduced the Aβ plaque deposition and the levels of soluble Aβ, accompanied with significantly decreased levels of activated microglia and systemic inflammatory factors. In conclusion, systemic transplantation of autologous Tregs may be an effective and safe intervention to prevent the progress of AD.

  6. Low-dimensional systems investigated by x-ray absorption spectroscopy: a selection of 2D, 1D and 0D cases

    NASA Astrophysics Data System (ADS)

    Mino, Lorenzo; Agostini, Giovanni; Borfecchia, Elisa; Gianolio, Diego; Piovano, Andrea; Gallo, Erik; Lamberti, Carlo

    2013-10-01

    Over the last three decades low-dimensional systems have attracted increasing interest both from the fundamental and technological points of view due to their unique physical and chemical properties. X-ray absorption spectroscopy (XAS) is a powerful tool for the characterization of such kinds of systems, owing to its chemical selectivity and high sensitivity in interatomic distance determination. Moreover, XAS does not require long-range ordering, that is usually absent in low-dimensional systems. Finally, this technique can simultaneously provide information on electronic and local structural properties of the nanomaterials, significantly contributing to clarify the relation between their atomic structure and their peculiar physical properties. This review provides a general introduction to XAS, discussing the basic theory of the technique, the most used detection modes, the related experimental setups and some complementary relevant characterization techniques (diffraction anomalous fine structure, extended energy-loss fine structure, pair distribution function, x-ray emission spectroscopy, high-energy resolution fluorescence detected XAS and x-ray Raman scattering). Subsequently, a selection of significant applications of XAS to two-, one- and zero-dimensional systems will be presented. The selected low-dimensional systems include IV and III-V semiconductor films, quantum wells, quantum wires and quantum dots; carbon-based nanomaterials (epitaxial graphene and carbon nanotubes); metal oxide films, nanowires, nanorods and nanocrystals; metal nanoparticles. Finally, the future perspectives for the application of XAS to nanostructures are discussed.

  7. Localized states in 1D Frenkel exciton systems: a comparison between infinite-range and nearest-neighbor transfer for normal and inverted bands.

    PubMed

    Avgin, I; Huber, D L

    2009-10-29

    We investigate localized states in one-dimensional Frenkel exciton systems that are created by a shift in the optical transition frequency of a single chromophore. In this paper, we focus on localized states lying below the exciton band that can act as exciton traps. A comparison is made between systems with infinite-range (r(-n), n = 2, 3, ...) transfer and those with nearest-neighbor (n = infinity) transfer. A distinction is also made between normal bands (minimum exciton energy at k = 0) and inverted bands (minimum energy at k = pi). The position of the localized state relative to the bottom of the band is calculated as a function of the shift in the single-chromophore transition frequency. The nature of the localized state is displayed in calculations of the participation ratio and the effective oscillator strength. Similarities and differences in localized states between normal and inverted band systems and between infinite-range and nearest-neighbor transfer are analyzed.

  8. Validating a 1-D SVAT model in a range of USA and Australian ecosystems: evidence towards its use as a tool to study Earth's system interactions

    NASA Astrophysics Data System (ADS)

    Petropoulos, G. P.; North, M. R.; Ireland, G.; Srivastava, P. K.; Rendall, D. V.

    2015-03-01

    This paper describes the validation of the SimSphere SVAT model conducted at different ecosystem types in the USA and Australia. Specific focus was given to examining the models' ability in predicting Shortwave Incoming Solar Radiation (Rg), Net Radiation (Rnet), Latent Heat (LE), Sensible Heat (H), Air Temperature at 1.3 m (Tair 1.3 m) and Air Temperature at 50 m (Tair 50 m). Model predictions were compared against corresponding in situ measurements acquired for a total of 72 selected days of the year 2011 obtained from 8 sites belonging to the AmeriFlux (USA) and OzFlux (Australia) monitoring networks. Selected sites were representative of a variety of environmental, biome and climatic conditions, to allow for the inclusion of contrasting conditions in the model evaluation. The application of the model confirmed its high capability in representing the multifarious and complex interactions of the Earth system. Comparisons showed a good agreement between modelled and measured fluxes, especially for the days with smoothed daily flux trends. A good to excellent agreement between the model predictions and the in situ measurements was reported, particularly so for the LE, H, T1.3 m and T 50 m parameters (RMSD = 39.47, 55.06 W m-2, 3.23, 3.77 °C respectively). A systematic underestimation of Rg and Rnet (RMSD = 67.83, 58.69 W m-2, MBE = 67.83, 58.69 W m-2 respectively) was also found. Highest simulation accuracies were obtained for the open woodland savannah and mulga woodland sites for most of the compared parameters. Very high values of the Nash-Sutcliffe efficiency index were also reported for all parameters ranging from 0.720 to 0.998, suggesting a very good model representation of the observations. To our knowledge, this study presents the first comprehensive validation of SimSphere, particularly so in USA and Australian ecosystem types. Findings are important and timely, given the rapidly expanding use of this model worldwide both as an educational and research

  9. 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.

  10. 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.

  11. 50 CFR 2.2 - Regional offices.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 1 2014-10-01 2014-10-01 false Regional offices. 2.2 Section 2.2 Wildlife... AGENCY ORGANIZATION AND LOCATIONS § 2.2 Regional offices. The U.S. Fish and Wildlife Service has eight... Complex, 911 NE. 11th Avenue, Portland, Oregon 97232. (b) Southwest Regional Office (Region...

  12. EMODEL_1D v. 1.0

    SciTech Connect

    Aldridge, David F.

    2016-07-06

    Program EMODEL_1D is an electromagnetic earth model construction utility designed to generate a three-dimensional (3D) uniformly-gridded representation of one-dimensional (1D) layered earth model. Each layer is characterized by the isotropic EM properties electric permittivity ?, magnetic permeability ?, and current conductivity ?. Moreover, individual layers of the model may possess a linear increase/decrease of any or all of these properties with depth.

  13. Polar discontinuities and 1D interfaces in monolayered materials

    NASA Astrophysics Data System (ADS)

    Martinez-Gordillo, Rafael; Pruneda, Miguel

    2015-12-01

    Interfaces are the birthplace of a multitude of fascinating discoveries in fundamental science, and have enabled modern electronic devices, from transistors, to lasers, capacitors or solar cells. These interfaces between bulk materials are always bi-dimensional (2D) 'surfaces'. However the advent of graphene and other 2D crystals opened up a world of possibilities, as in this case the interfaces become one-dimensional (1D) lines. Although the properties of 1D nanoribbons have been extensively discussed in the last few years, 1D interfaces within infinite 2D systems had remained mostly unexplored until very recently. These include grain boundaries in polycrystalline samples, or interfaces in hybrid 2D sheets composed by segregated domains of different materials (as for example graphene/BN hybrids, or chemically different transition metal dichalcogenides). As for their 2D counterparts, some of these 1D interfaces exhibit polar characteristics, and can give rise to fascinating new physical properties. Here, recent experimental discoveries and theoretical predictions on the polar discontinuities that arise at these 1D interfaces will be reviewed, and the perspectives of this new research topic, discussed.

  14. Heat Capacity of 1D Molecular Chains

    NASA Astrophysics Data System (ADS)

    Bagatskii, M. I.; Barabashko, M. S.; Sumarokov, V. V.; Jeżowski, A.; Stachowiak, P.

    2017-04-01

    The heat capacity of 1D chains of nitrogen and methane molecules (adsorbed in the outer grooves of bundles of closed-cap single-walled carbon nanotubes) has been studied in the temperature ranges 2-40 and 2-60 K, respectively. The temperature dependence of the heat capacity of 1D chains of nitrogen molecules below 3 K is close to a linear. It was found that the rotational heat capacity of methane molecules is a significant part of the total heat capacity of the chains throughout the whole investigated temperature range, whereas in the case of nitrogen, the librations are significant only above 15 K. The dependence of the heat capacity for methane below 10 K indicates the presence of a Schottky anomaly caused by the tunneling between the lowest energy levels of the CH4 molecule rotational spectra. Characteristic features observed in the temperature dependence of the heat capacity of 1D methane crystals are also discussed.

  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. Phosphorylation of a Herpes Simplex Virus 1 dUTPase by a Viral Protein Kinase, Us3, Dictates Viral Pathogenicity in the Central Nervous System but Not at the Periphery

    PubMed Central

    Kato, Akihisa; Shindo, Keiko; Maruzuru, Yuhei

    2014-01-01

    ABSTRACT Herpes simplex virus 1 (HSV-1) encodes Us3 protein kinase, which is critical for viral pathogenicity in both mouse peripheral sites (e.g., eyes and vaginas) and in the central nervous systems (CNS) of mice after intracranial and peripheral inoculations, respectively. Whereas some Us3 substrates involved in Us3 pathogenicity in peripheral sites have been reported, those involved in Us3 pathogenicity in the CNS remain to be identified. We recently reported that Us3 phosphorylated HSV-1 dUTPase (vdUTPase) at serine 187 (Ser-187) in infected cells, and this phosphorylation promoted viral replication by regulating optimal enzymatic activity of vdUTPase. In the present study, we show that the replacement of vdUTPase Ser-187 by alanine (S187A) significantly reduced viral replication and virulence in the CNS of mice following intracranial inoculation and that the phosphomimetic substitution at vdUTPase Ser-187 in part restored the wild-type viral replication and virulence. Interestingly, the S187A mutation in vdUTPase had no effect on viral replication and pathogenic effects in the eyes and vaginas of mice after ocular and vaginal inoculation, respectively. Similarly, the enzyme-dead mutation in vdUTPase significantly reduced viral replication and virulence in the CNS of mice after intracranial inoculation, whereas the mutation had no effect on viral replication and pathogenic effects in the eyes and vaginas of mice after ocular and vaginal inoculation, respectively. These observations suggested that vdUTPase was one of the Us3 substrates responsible for Us3 pathogenicity in the CNS and that the CNS-specific virulence of HSV-1 involved strict regulation of vdUTPase activity by Us3 phosphorylation. IMPORTANCE Herpes simplex virus 1 (HSV-1) encodes a viral protein kinase Us3 which is critical for pathogenicity both in peripheral sites and in the central nervous systems (CNS) of mice following peripheral and intracranial inoculations, respectively. Whereas some Us3

  17. Glass-based 1-D dielectric microcavities

    NASA Astrophysics Data System (ADS)

    Chiasera, Alessandro; Scotognella, Francesco; Valligatla, Sreeramulu; Varas, Stefano; Jasieniak, Jacek; Criante, Luigino; Lukowiak, Anna; Ristic, Davor; Gonçalves, Rogeria Rocha; Taccheo, Stefano; Ivanda, Mile; Righini, Giancarlo C.; Ramponi, Roberta; Martucci, Alessandro; Ferrari, Maurizio

    2016-11-01

    We have developed a reliable RF sputtering techniques allowing to fabricate glass-based one dimensional microcavities, with high quality factor. This property is strongly related to the modification of the density of states due to the confinement of the gain medium in a photonic band gap structure. In this short review we present some of the more recent results obtained by our team exploiting these 1D microcavities. In particular we present: (1) Er3+ luminescence enhancement of the 4I13/2 → 4I15/2 transition; (2) broad band filters based on disordered 1-D photonic structures; (3) threshold defect-mode lasing action in a hybrid structure.

  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. The alpha(1D)-adrenergic receptor directly regulates arterial blood pressure via vasoconstriction.

    PubMed

    Tanoue, Akito; Nasa, Yoshihisa; Koshimizu, Takaaki; Shinoura, Hitomi; Oshikawa, Sayuri; Kawai, Takayuki; Sunada, Sachie; Takeo, Satoshi; Tsujimoto, Gozoh

    2002-03-01

    To investigate the physiological role of the alpha(1D)-adrenergic receptor (alpha(1D)-AR) subtype, we created mice lacking the alpha(1D)-AR (alpha(1D)(-/-)) by gene targeting and characterized their cardiovascular function. In alpha(1D)-/- mice, the RT-PCR did not detect any transcript of the alpha(1D)-AR in any tissue examined, and there was no apparent upregulation of other alpha(1)-AR subtypes. Radioligand binding studies showed that alpha(1)-AR binding capacity in the aorta was lost, while that in the heart was unaltered in alpha(1D)-/- mice. Non-anesthetized alpha(1D)-/- mice maintained significantly lower basal systolic and mean arterial blood pressure conditions, relative to wild-type mice, and they showed no significant change in heart rate or in cardiac function, as assessed by echocardiogram. Besides hypotension, the pressor responses to phenylephrine and norepinephrine were decreased by 30-40% in alpha(1D)-/- mice. Furthermore, the contractile response of the aorta and the pressor response of isolated perfused mesenteric arterial beds to alpha(1)-AR stimulation were markedly reduced in alpha(1D)-/- mice. We conclude that the alpha(1D)-AR participates directly in sympathetic regulation of systemic blood pressure by vasoconstriction.

  20. 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.

  1. 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.

  2. The stability of 1-D soliton in transverse direction

    NASA Astrophysics Data System (ADS)

    Verma, Deepa; Bera, Ratan Kumar; Das, Amita; Kaw, Predhiman

    2016-12-01

    The complete characterization of the exact 1-D solitary wave solutions (both stationary and propagating) for light plasma coupled system have been studied extensively in the parameter space of light frequency and the group speed [Poornakala et al., Phys. Plasmas 9(5), 1820 (2002)]. It has been shown in 1-D that solutions with single light wave peak and paired structures are stable and hence long lived. However, solutions having multiple peaks of light wave are unstable due to Raman scattering instability [Saxena et al., Phys. Plasmas 14, 072307 (2007)]. Here, we have shown with the help of 2-D fluid simulation that single peak and paired solutions too get destabilized by the transverse filamentation instability. The numerical growth rates obtained from simulations is seen to compare well with the analytical values. It is also shown that multiple peaks solitons first undergo the regular 1-D forward Raman scattering instability. Subsequently, they undergo a distinct second phase of destabilization through transverse filamentation instability. This is evident from the structure as well as the plot of the perturbed energy which shows a second phase of growth after saturating initially. The growth rate of the filamentation instability being comparatively slower than the forward Raman instability this phase comes quite late and is clearly distinguishable.

  3. 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.

  4. 75 FR 27411 - Airworthiness Directives; Turbomeca Arriel 1B, 1D, 1D1, and 1S1 Turboshaft Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-17

    ... (that incorporate Turbomeca Modification (mod) TU 148), Arriel 1D, 1D1, and 1S1 turboshaft engines that do not incorporate mod TU 347. That AD also requires initial and repetitive replacements of 2nd stage... incorporate mod TU 148), 1D, 1D1, and 1S1 turboshaft engines that do not incorporate mod TU 347. We...

  5. 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.

  6. A new potential energy surface for the H2S system and dynamics study on the S(1D) + H2(X1Σg+) reaction

    PubMed Central

    Yuan, Jiuchuang; He, Di; Chen, Maodu

    2015-01-01

    We constructed a new global potential energy surface (PES) for the electronic ground state (1A′) of H2S based on 21,300 accurate ab initio energy points over a large configuration space. The ab initio energies are obtained from multireference configuration interaction calculations with a Davidson correction using basis sets of quadruple zeta quality. The neural network method is applied to fit the PES, and the root mean square error of fitting is small (1.68 meV). Time-dependent wave packet studies for the S(1D) + H2(X1Σg+) → H(2S) + SH(X2Π) reaction on the new PES are conducted to study the reaction dynamics. The calculated integral cross sections decrease with increasing collision energy and remain fairly constant within the high collision energy range. Both forward and backward scatterings can be observed as expected for a barrierless reaction with a deep well on the PES. The calculated integral cross sections and differential cross sections are in good agreement with the experimental results. PMID:26435516

  7. 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.

  8. Lesions to the CA2 region of the hippocampus impair social memory in mice

    PubMed Central

    Stevenson, Erica L.; Caldwell, Heather K.

    2014-01-01

    The function of the CA2 region of the hippocampus is poorly understood. While the CA1 and CA3 regions have been extensively studied, for years the CA2 region has primarily been viewed as a linking area between the two. However, the CA2 region is known to have distinct neurochemical and structural features that are different from the other parts of hippocampus and in recent years it has been suggested that the CA2 region may play a role in the formation and or recall of olfactory-based memories needed for normal social behavior. While this hypothesis has been supported by hippocampal lesion studies that have included the CA2 region, no studies have attempted to specifically lesion the CA2 region of the hippocampus in mice to determine the effects on social recognition memory and olfaction. To fill this knowledge gap, we sought to perform excitotoxic N-methyl-D aspartate (NMDA) lesions of the CA2 region in mice and determine the effects on social recognition memory. We predicted that lesions of the CA2 region would impair social recognition memory. We then went on to test olfaction in CA2 lesioned mice since social memory requires a functional olfactory system. Consistent with our prediction, we found that CA2 lesioned animals have impaired social recognition. These findings are significant because they confirm that the CA2 region of the hippocampus is a part of the neural circuitry that regulates social recognition memory, which may have implications for our understanding of the neural regulation of social behavior across species. PMID:25131412

  9. Constitutive modeling and control of 1D smart composite structures

    NASA Astrophysics Data System (ADS)

    Briggs, Jonathan P.; Ostrowski, James P.; Ponte-Castaneda, Pedro

    1998-07-01

    Homogenization techniques for determining effective properties of composite materials may provide advantages for control of stiffness and strain in systems using hysteretic smart actuators embedded in a soft matrix. In this paper, a homogenized model of a 1D composite structure comprised of shape memory alloys and a rubber-like matrix is presented. With proportional and proportional/integral feedback, using current as the input state and global strain as an error state, implementation scenarios include the use of tractions on the boundaries and a nonlinear constitutive law for the matrix. The result is a simple model which captures the nonlinear behavior of the smart composite material system and is amenable to experiments with various control paradigms. The success of this approach in the context of the 1D model suggests that the homogenization method may prove useful in investigating control of more general smart structures. Applications of such materials could include active rehabilitation aids, e.g. wrist braces, as well as swimming/undulating robots, or adaptive molds for manufacturing processes.

  10. Blood flow quantification using 1D CFD parameter identification

    NASA Astrophysics Data System (ADS)

    Brosig, Richard; Kowarschik, Markus; Maday, Peter; Katouzian, Amin; Demirci, Stefanie; Navab, Nassir

    2014-03-01

    Patient-specific measurements of cerebral blood flow provide valuable diagnostic information concerning cerebrovascular diseases rather than visually driven qualitative evaluation. In this paper, we present a quantitative method to estimate blood flow parameters with high temporal resolution from digital subtraction angiography (DSA) image sequences. Using a 3D DSA dataset and a 2D+t DSA sequence, the proposed algorithm employs a 1D Computational Fluid Dynamics (CFD) model for estimation of time-dependent flow values along a cerebral vessel, combined with an additional Advection Diffusion Equation (ADE) for contrast agent propagation. The CFD system, followed by the ADE, is solved with a finite volume approximation, which ensures the conservation of mass. Instead of defining a new imaging protocol to obtain relevant data, our cost function optimizes the bolus arrival time (BAT) of the contrast agent in 2D+t DSA sequences. The visual determination of BAT is common clinical practice and can be easily derived from and be compared to values, generated by a 1D-CFD simulation. Using this strategy, we ensure that our proposed method fits best to clinical practice and does not require any changes to the medical work flow. Synthetic experiments show that the recovered flow estimates match the ground truth values with less than 12% error in the mean flow rates.

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

    NASA Astrophysics Data System (ADS)

    Zhu, Y.; Appenzeller, J.

    2015-10-01

    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.

  12. 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.

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

    SciTech Connect

    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.

  14. Diagnostics from a 1-D atmospheric column

    SciTech Connect

    Flatley, J.M.; Mace, G.

    1996-04-01

    Various diagnostics were computed from an array of radiosondes during an intensive field operation arranged by the Atmospheric Radiation Measurement Program. The network data was centered around the site at Lamont, Oklahoma. The apparent heat source and apparent moisture sink were computed and compared to the kinematic vertical velocity for both real data and the mesoscale analysis and prediction system. Three different case studies of various weathe regimes were examined.

  15. 1-D ELECTRO-OPTIC BEAM STEERING DEVICE.

    PubMed

    Wang, Wei-Chih; Tsui, Chi Leung

    2011-06-05

    In this paper, we present the design and fabrication of a 1D beam steering device based on planar electro-optic thermal-plastic prisms and a collimator lens array. With the elimination of moving parts, the proposed device is able to overcome the mechanical limitations of present scanning devices, such as fatigue and low operating frequency, while maintaining a small system footprint (~0.5mm×0.5mm). From experimental data, our prototype device is able to achieve a maximum deflection angle of 5.6° for a single stage prism design and 29.2° for a cascaded three prisms stage design. The lens array shows a 4µm collimated beam diameter.

  16. Combinatorial approach to exactly solve the 1D Ising model

    NASA Astrophysics Data System (ADS)

    Seth, Swarnadeep

    2017-01-01

    The Ising model is a well known statistical model which can be solved exactly by various methods. The most familiar one is the transfer matrix method. Sometimes it can be difficult to approach the open boundary case rather than periodic boundary ones in higher dimensions. But physically it is more intuitive to study the open boundary case, as it gives a closer view of the real system. We have introduced a new method called the pairing method to determine the exact partition function for the simplest case, a 1D Ising lattice. This method simplifies the problem's complexities and reduces it to a pure combinatorial problem. The study also reveals that it is possible to apply this pairing method in the case of a 2D square lattice. The obtained results agree perfectly with the values in the literature and this new approach provides an algorithmic insight to deal with such problems.

  17. 1-D ELECTRO-OPTIC BEAM STEERING DEVICE

    PubMed Central

    Wang, Wei-Chih; Tsui, Chi Leung

    2011-01-01

    In this paper, we present the design and fabrication of a 1D beam steering device based on planar electro-optic thermal-plastic prisms and a collimator lens array. With the elimination of moving parts, the proposed device is able to overcome the mechanical limitations of present scanning devices, such as fatigue and low operating frequency, while maintaining a small system footprint (~0.5mm×0.5mm). From experimental data, our prototype device is able to achieve a maximum deflection angle of 5.6° for a single stage prism design and 29.2° for a cascaded three prisms stage design. The lens array shows a 4µm collimated beam diameter. PMID:22199458

  18. Lanczos diagonalizations of the 1-D Peierls-Hubbard model

    SciTech Connect

    Loh, E.Y.; Campbell, D.K.; Gammel, J.T.

    1989-01-01

    In studies of interacting electrons in reduced dimensions'' one is trapped between the Scylla of exponential growth of the number of states in any exact many-body basis and the Charybdis of the failure of mean-field theories to capture adequately the effects of interactions. In the present article we focus on one technique -- the Lanczos method -- which, at least in the case of the 1-D Peierls-Hubbard model, appears to allow us to sail the narrow channel between these two hazards. In contrast to Quantum Monte Carlo methods, which circumvent the exponential growth of states by statistical techniques and importance sampling, the Lanczos approach attacks this problem head-on by diagonalizing the full Hamiltonian. Given the restrictions of present computers, this approach is thus limited to studying finite clusters of roughly 12--14 sites. Fortunately, in one dimension, such clusters are usually sufficient for extracting many of the properties of the infinite system provided that one makes full use of the ability to vary the boundary conditions. In this article we shall apply the Lanczos methodology and novel phase randomization'' techniques to study the 1-D Peierls-Hubbard model, with particular emphasis on the optical absorption properties, including the spectrum of absorptions as a function of photon energy. Despite the discreteness of the eigenstates in our finite clusters, we are able to obtain optical spectra that, in cases where independent tests can be made, agree well with the known exact results for the infinite system. Thus we feel that this combination of techniques represents an important and viable means of studying many interesting novel materials involving strongly correlated electrons. 26 refs., 6 figs.

  19. 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.

  20. Circadian system functionality, hippocampal oxidative stress, and spatial memory in the APPswe/PS1dE9 transgenic model of Alzheimer disease: effects of melatonin or ramelteon.

    PubMed

    Baño Otalora, Beatriz; Popovic, Natalija; Gambini, Juan; Popovic, Miroljub; Viña, José; Bonet-Costa, Vicent; Reiter, Russel J; Camello, Pedro Javier; Rol, Maria Ángeles; Madrid, Juan Antonio

    2012-08-01

    Alzheimer disease (AD) is a neurodegenerative disorder that primarily causes β-amyloid accumulation in the brain, resulting in cognitive and behavioral deficits. AD patients, however, also suffer from severe circadian rhythm disruptions, and the underlying causes are still not fully known. Patients with AD show reduced systemic melatonin levels. This may contribute to their symptoms, since melatonin is an effective chronobiotic and antioxidant with neuroprotective properties. Here, the authors critically assessed the effects of long-term melatonin treatment on circadian system function, hippocampal oxidative stress, and spatial memory performance in the APPswe/PS1 double transgenic (Tg) mouse model of AD. To test if melatonin MT1/MT2 receptor activation, alone, was involved, the authors chronically treated some mice with the selective MT1/MT2 receptor agonist ramelteon. The results indicate that many of the circadian and behavioral parameters measured, including oxidative stress markers, were not significantly affected in these AD mice. During the day, though, Tg controls (Tg-CON) showed significantly higher mean activity and body temperature (BT) than wild-type (WT) mice. Overall, BT rhythm amplitude was significantly lower in Tg than in WT mice. Although melatonin treatment had no effect, ramelteon significantly reduced the amplitude of the BT rhythm in Tg mice. Towards the end of the experiment, Tg mice treated with ramelteon (Tg-RAM) showed significantly higher circadian rhythm fragmentation than Tg-CON and reduced circadian BT rhythm strength. The free-running period (τ) for the BT and locomotor activity (LA) rhythms of Tg-CON was <24 h. Whereas melatonin maintained τ at 24 h for BT and LA in both genotypes, ramelteon treatment had no effect. In the behavioral tests, the number of approaches and time spent exploring novel objects were significantly higher in Tg-CON than WT controls. Brain tissue analysis revealed significant reduction in hippocampal protein

  1. Data Management Systems (DMS): Complex data types study. Volume 1: Appendices A-B. Volume 2: Appendices C1-C5. Volume 3: Appendices D1-D3 and E

    NASA Technical Reports Server (NTRS)

    Leibfried, T. F., Jr.; Davari, Sadegh; Natarajan, Swami; Zhao, Wei

    1992-01-01

    Two categories were chosen for study: the issue of using a preprocessor on Ada code of Application Programs which would interface with the Run-Time Object Data Base Standard Services (RODB STSV), the intent was to catch and correct any mis-registration errors of the program coder between the user declared Objects, their types, their addresses, and the corresponding RODB definitions; and RODB STSV Performance Issues and Identification of Problems with the planned methods for accessing Primitive Object Attributes, this included the study of an alternate storage scheme to the 'store objects by attribute' scheme in the current design of the RODB. The study resulted in essentially three separate documents, an interpretation of the system requirements, an assessment of the preliminary design, and a detailing of the components of a detailed design.

  2. Brady 1D seismic velocity model ambient noise prelim

    SciTech Connect

    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.

  3. Co-localization of L-type voltage dependent calcium channel alpha 1D subunit (Ca(v)1.3) and calbindin (CB) in the mouse central nervous system.

    PubMed

    Xu, Jie Hua; Yang, Zhen Bang; Wang, Hui; Tang, Feng-Ru

    2014-02-21

    Previous study has shown that the co-localization of calbindin (CB) with L-type voltage dependent Ca(2+) channel (VDCC) alpha 1C subunit (Ca(v)1.2) in the rat insulinoma 1046-38 (RIN) beta cells may play an important regulatory role in Ca(2+) influx and exocytosis of insulin granules. In the present study, L-type voltage dependent Ca(2+) channel (VDCC) and calbindin (CB) were demonstrated in different regions of the mouse central nervous system (CNS). Double labeling immunofluorescence staining showed a co-localization of Ca(v)1.3 and CB. The co-localization of Ca(v)1.3 and CB in certain brain regions such as the hippocampus suggests their important roles in neuroplasticity. The relative high percentages of co-localization of Ca(v)1.3 with CB in the laminae II of the dorsal horn of the spinal cord indicate that the regulation mechanism of nociceptive transmission may be related with both VDCC and Ca(2+) binding protein.

  4. Engineered Solution-Liquid-Solid Growth of a "Treelike" 1D/1D TiO2 Nanotube-CdSe Nanowire Heterostructure: Photoelectrochemical Conversion of Broad Spectrum of Solar Energy.

    PubMed

    Mukherjee, Bratindranath; Sarker, Swagotom; Crone, Eric; Pathak, Pawan; Subramanian, Vaidyanathan R

    2016-12-07

    This work presents a hitherto unreported approach to assemble a 1D oxide-1D chalcogenide heterostructured photoactive film. As a representative system, bismuth (Bi) catalyzed 1D CdSe nanowires are directly grown on anodized 1D TiO2 nanotube (T_NT). A combination of the reductive successive-ionic-layer-adsorption-reaction (R-SILAR) and the solution-liquid-solid (S-L-S) approach is implemented to fabricate this heterostructured assembly, reported in this 1D/1D form for the first time. XRD, SEM, HRTEM, and elemental mapping are performed to systematically characterize the deposition of bismuth on T_NT and the growth of CdSe nanowires leading to the evolution of the 1D/1D heterostructure. The resulting "treelike" photoactive architecture demonstrates UV-visible light-driven electron-hole pair generation. The photoelectrochemical results highlight: (i) the formation of a stable n-n heterojunction between TiO2 nanotube and CdSe nanowire, (ii) an excellent correlation between the absorbance vis-à-vis light conversion efficiency (IPCE), and (iii) a photocurrent density of 3.84 mA/cm(2). This proof-of-concept features the viability of the approach for designing such complex 1D/1D oxide-chalcogenide heterostructures that can be of interest to photovoltaics, photocatalysis, environmental remediation, and sensing.

  5. 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.

  6. 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

  7. 9 CFR 95.2 - Region of origin.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Region of origin. 95.2 Section 95.2... BYPRODUCTS (EXCEPT CASINGS), AND HAY AND STRAW, OFFERED FOR ENTRY INTO THE UNITED STATES § 95.2 Region of... Administrator, Veterinary Services, the name of the region of origin of such product or material: Provided,...

  8. 43 CFR 3420.2 - Regional leasing levels.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false Regional leasing levels. 3420.2 Section... MANAGEMENT, DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) COMPETITIVE LEASING Competitive Leasing § 3420.2 Regional leasing levels. This section sets out the process to be followed in...

  9. Controlled Growth of 1D MoSe2 Nanoribbons with Spatially Modulated Edge States.

    PubMed

    Cheng, Fang; Xu, Hai; Xu, Wentao; Zhou, Pinjia; Martin, Jens; Loh, Kian Ping

    2017-02-08

    Two-dimensional (2D) transition metal dichalcogenides (TMDCs) possess interesting one-dimensional (1D) properties at its edges and inversion domain boundaries, where properties markedly different from the 2D basal plane, such as 1D metallicity and charge density waves, can be observed. Although 2D TMDCs crystals are widely grown by chemical vapor deposition (CVD), the fabrication of 1D TMDCs ribbons is challenging due to the difficulty to confine growth in only one dimension. Here we report the controlled growth of MoSe2 nanoribbons with an aspect ratio >100 by using prepatterned Se reconstructions on Au(100). Using scanning tunneling microscope and spectroscopy (STM/STS), the atomic and electronic structure of MoSe2 nanoribbons are studied. The ultranarrow ribbons show metallic behavior, while wider ribbons show a crossover from metallic to semiconducting behavior going from the edge to the center of the ribbon. The observed conductance modulations of the ultranarrow ribbons are attributed to 1D Moiré pattern. Remarkably, it shows a different periodicity compared with the 2D Moiré pattern in wider ribbons indicating that the 1D system is softened due to the high ratio of edge to basal plane bonds. Further, we demonstrated that the nanoribbons are stable against ambient conditions, which suggests that 1D TMDCs can be exploited for further applications.

  10. 1D-Var assimilation of TMI and SSM/I observations in rainy areas

    NASA Astrophysics Data System (ADS)

    Moreau, E.; Lopez, P.; Bauer, P.

    2003-04-01

    The assimilation of observations related to cloud and precipitation has become a very important issue for most operational weather services including ECMWF. A 1D-Var method was developed by Marécal and Mahfouf (2000) for correcting individual profiles of the model's control variables in order to decrease the discrepancies that often exist between the simulated surface rainfall rates and corresponding retrievals obtained from TMI or SSM/I microwave measurements. Instead of performing the 1D-Var on surface rainfall rates that are derived from multi-channel microwave brightness temperatures (BTs) thanks to various algorithms, the 1D-Var calculations have been applied to the BTs directly. The multiple sensitivities of the BTs to the vertically integrated amounts of rain water and cloud water should provide a stronger constraint on the 1D-Var minimization. Another advantage of this method could result from the better knowledge of the errors on observed BTs than on derived rainfall rates. The potential of applying 1D-Var directly to TMI and SSM/I microwave brightness temperatures has been investigated in this study and its results have been compared with the 1D-Var with derived rainfall rates. Results are presented for a pacific super-typhoon and for a north-atlantic extratropical front. A comparison of the retrieved rain profiles using both methods with rain information deduced from the TRMM precipitation radar (PR) is also presented. Additional direct comparisons with the PR reflectivities will be shown by A. Benedetti (2003). Following the work by Marécal and Mahfouf (2002), indirect "1D-Var + 4D-Var" assimilation experiments will be performed. In this approach, the temperature and humidity increments provided by the 1D-Var are first converted into total column water vapour pseudo-observations that are in turn assimilated in ECMWF's 4D-Var system.

  11. 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.

  12. 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.

  13. 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

  14. On the origin of multi-step spin transition behaviour in 1D nanoparticles

    NASA Astrophysics Data System (ADS)

    Chiruta, Daniel; Jureschi, Catalin-Maricel; Linares, Jorge; Dahoo, Pierre Richard; Garcia, Yann; Rotaru, Aurelian

    2015-09-01

    To investigate the spin state switching mechanism in spin crossover (SCO) nanoparticles, a special attention is given to three-step thermally induced SCO behavior in 1D chains. An additional term is included in the standard Ising-like Hamiltonian to account for the border interaction between SCO molecules and its local environment. It is shown that this additional interaction, together with the short range interaction, drives the multi-steps thermal hysteretic behavior in 1D SCO systems. The relation between a polymeric matrix and this particular multi-step SCO phenomenon is discussed accordingly. Finally, the environmental influence on the SCO system's size is analyzed as well.

  15. Rab28 is a TBC1D1/TBC1D4 substrate involved in GLUT4 trafficking.

    PubMed

    Zhou, Zhou; Menzel, Franziska; Benninghoff, Tim; Chadt, Alexandra; Du, Chen; Holman, Geoffrey D; Al-Hasani, Hadi

    2017-01-01

    The Rab-GTPase-activating proteins (GAPs) TBC1D1 and TBC1D4 play important roles in the insulin-stimulated translocation of the glucose transporter GLUT4 from intracellular vesicles to the plasma membrane in muscle cells and adipocytes. We identified Rab28 as a substrate for the GAP domains of both TBC1D1 and TBC1D4 in vitro. Rab28 is expressed in adipose cells and skeletal muscle, and its GTP-binding state is acutely regulated by insulin. We found that in intact isolated mouse skeletal muscle, siRNA-mediated knockdown of Rab28 decreases basal glucose uptake. Conversely, in primary rat adipose cells, overexpression of Rab28-Q72L, a constitutively active mutant, increases basal cell surface levels of an epitope-tagged HA-GLUT4. Our results indicate that Rab28 is a novel GTPase involved in the intracellular retention of GLUT4 in insulin target cells.

  16. 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.

  17. Lesion of the tuberomammillary nucleus E2-region attenuates postictal seizure protection in rats.

    PubMed

    Jin, Chun-Lei; Zhuge, Zheng-Bing; Wu, Deng-Chang; Zhu, Yuan-Yuan; Wang, Shuang; Luo, Jian-Hong; Chen, Zhong

    2007-03-01

    Postictal seizure protection (PSP) is an endogenous anticonvulsant phenomenon that follows an epileptic seizure and inhibits the induction of further seizures. The tuberomammillary nucleus (TM), located in the posterior hypothalamus, consists of five subregions and is the sole source of histaminergic neurons in the brain. To determine whether the TM is involved in PSP in rats, we tested the effects of bilateral electrolytic lesions of the TM E2-region on seizures induced by intermittent maximal electroshock (MES). The TM E2-region lesions significantly attenuated PSP during the intermittent MES procedure. Furthermore, intracerebroventricular injection of alpha-fluoromethylhistidine (100 microg), a selective and irreversible histidine decarboxylase inhibitor, mimicked the attenuation of PSP induced by the lesion of TM E2-region. In addition, neurochemical experiments revealed that the TM E2-region lesions markedly decreased basal histamine levels in the cortex, hippocampus, brainstem and hypothalamus, but had no significant effect on basal glutamate and GABA levels. Moreover, intermittent MES induced a persistent decrease of brain histamine levels in both sham-operated and lesioned rats. These results indicate that through its intrinsic histaminergic system, the TM may exert powerful inhibitory function during the intermittent MES procedure and actively participate in the mechanisms of PSP.

  18. Ion-sensing properties of 1D vanadium pentoxide nanostructures

    PubMed Central

    2012-01-01

    The application of one-dimensional (1D) V2O5·nH2O nanostructures as pH sensing material was evaluated. 1D V2O5·nH2O nanostructures were obtained by a hydrothermal method with systematic control of morphology forming different nanostructures: nanoribbons, nanowires and nanorods. Deposited onto Au-covered substrates, 1D V2O5·nH2O nanostructures were employed as gate material in pH sensors based on separative extended gate FET as an alternative to provide FET isolation from the chemical environment. 1D V2O5·nH2O nanostructures showed pH sensitivity around the expected theoretical value. Due to high pH sensing properties, flexibility and low cost, further applications of 1D V2O5·nH2O nanostructures comprise enzyme FET-based biosensors using immobilized enzymes. PMID:22709724

  19. Entangling strings of neutral atoms in 1D atomic pipeline structures.

    PubMed

    Dorner, U; Fedichev, P; Jaksch, D; Lewenstein, M; Zoller, P

    2003-08-15

    We study a string of neutral atoms with nearest neighbor interaction in a 1D beam splitter configuration, where the longitudinal motion is controlled by a moving optical lattice potential. The dynamics of the atoms crossing the beam splitter maps to a 1D spin model with controllable time dependent parameters, which allows the creation of maximally entangled states of atoms by crossing a quantum phase transition. Furthermore, we show that this system realizes protected quantum memory, and we discuss the implementation of one- and two-qubit gates in this setup.

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

    PubMed

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

    2016-03-07

    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.

  1. 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).

  2. 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

  3. 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.

  4. 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.

  5. 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.

  6. Spatio-temporal stability of 1D Kerr cavity solitons

    NASA Astrophysics Data System (ADS)

    Gelens, L.; Parra-Rivas, P.; Leo, F.; Gomila, D.; Matias, Manuel A.; Coen, S.

    2014-05-01

    The Lugiato-Lefever equation (LLE) has been extensively studied since its derivation in 1987, when this meanfield model was introduced to describe nonlinear optical cavities. The LLE was originally derived to describe a ring cavity or a Fabry-Perot resonator with a transverse spatial extension and partially filled with a nonlinear medium but it has also been shown to be applicable to other types of cavities, such as fiber resonators and microresonators. Depending on the parameters used, the LLE can present a monostable or bistable input-output response curve. A large number of theoretical studies have been done in the monostable regime, but the bistable regime has remained widely unexplored. One of the reasons for this was that previous experimental setups were not able to works in such regimes of the parameter space. Nowadays the possibility of reaching such parameter regimes experimentally has renewed the interest in the LLE. In this contribution, we present an in-depth theoretical study of the different dynamical regimes that can appear in parameter space, focusing on the dynamics of localized solutions, also known as cavity solitons (CSs). We show that time-periodic oscillations of a 1D CS appear naturally in a broad region of parameter space. More than this oscillatory regime, which has been recently demonstrated experimentally,1 we theoretically report on several kinds of chaotic dynamics. We show that the existence of CSs and their dynamics is related with the spatial dynamics of the system and with the presence of a codimension-2 point known as a Fold-Hopf bifurcation point. These dynamical regimes can become accessible by using devices such as microresonators, for instance widely used for creating optical frequency combs.

  7. 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.

  8. Characterization of the Interaction of Staphylococcal Entertoxin B with CD1d Expressed in Human Renal Proximal Tubule Epithelial Cells

    DTIC Science & Technology

    2015-02-04

    typical antigen recognition process that recruits the major histocompatibility complex class II (MHC II) molecules. The immunological importance of CD1d is...underscored by its influences on the performances of natural killer T-cells and thereby mediates the innate and adaptive immune systems. Results...release of many cytokines, and thereby systematically in- fluences the hosts’ adaptive and innate immune systems [35,36]. The involvement of CD1d in

  9. 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.

  10. 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.

  11. Ultrahigh-Q nanocavity with 1D photonic gap.

    PubMed

    Notomi, M; Kuramochi, E; Taniyama, H

    2008-07-21

    Recently, various wavelength-sized cavities with theoretical Q values of approximately 10(8) have been reported, however, they all employ 2D or 3D photonic band gaps to realize strong light confinement. Here we numerically demonstrate that ultrahigh-Q (2.0x10(8)) and wavelength-sized (V(eff) approximately 1.4(lambda/n)3) cavities can be achieved by employing only 1D periodicity.

  12. Nonreciprocity of edge modes in 1D magnonic crystal

    NASA Astrophysics Data System (ADS)

    Lisenkov, I.; Kalyabin, D.; Osokin, S.; Klos, J. W.; Krawczyk, M.; Nikitov, S.

    2015-03-01

    Spin waves propagation in 1D magnonic crystals is investigated theoretically. Mathematical model based on plane wave expansion method is applied to different types of magnonic crystals, namely bi-component magnonic crystal with symmetric/asymmetric boundaries and ferromagnetic film with periodically corrugated top surface. It is shown that edge modes in magnonic crystals may exhibit nonreciprocal behaviour at much lower frequencies than in homogeneous films.

  13. Emergent 1d Ising Behavior in AN Elementary Cellular Automaton Model

    NASA Astrophysics Data System (ADS)

    Kassebaum, Paul G.; Iannacchione, Germano S.

    The fundamental nature of an evolving one-dimensional (1D) Ising model is investigated with an elementary cellular automaton (CA) simulation. The emergent CA simulation employs an ensemble of cells in one spatial dimension, each cell capable of two microstates interacting with simple nearest-neighbor rules and incorporating an external field. The behavior of the CA model provides insight into the dynamics of coupled two-state systems not expressible by exact analytical solutions. For instance, state progression graphs show the causal dynamics of a system through time in relation to the system's entropy. Unique graphical analysis techniques are introduced through difference patterns, diffusion patterns, and state progression graphs of the 1D ensemble visualizing the evolution. All analyses are consistent with the known behavior of the 1D Ising system. The CA simulation and new pattern recognition techniques are scalable (in both dimension, complexity, and size) and have many potential applications such as complex design of materials, control of agent systems, and evolutionary mechanism design.

  14. Examining Prebiotic Chemistry Using O(^1D) Insertion Reactions

    NASA Astrophysics Data System (ADS)

    Hays, Brian M.; Laas, Jacob C.; Weaver, Susanna L. Widicus

    2013-06-01

    Aminomethanol, methanediol, and methoxymethanol are all prebiotic molecules expected to form via photo-driven grain surface chemistry in the interstellar medium (ISM). These molecules are expected to be precursors for larger, biologically-relevant molecules in the ISM such as sugars and amino acids. These three molecules have not yet been detected in the ISM because of the lack of available rotational spectra. A high resolution (sub)millimeter spectrometer coupled to a molecular source is being used to study these molecules using O(^1D) insertion reactions. The O(^1D) chemistry is initiated using an excimer laser, and the products of the insertion reactions are adiabatically cooled using a supersonic expansion. Experimental parameters are being optimized by examination of methanol formed from O(^1D) insertion into methane. Theoretical studies of the structure and reaction energies for aminomethanol, methanediol, and methoxymethanol have been conducted to guide the laboratory studies once the methanol experiment has been optimized. The results of the calculations and initial experimental results will be presented.

  15. 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.

  16. Synthesis, characterization and photocatalytic activity of 1D TiO2 nanostructures.

    PubMed

    Cabrera, Julieta; Alarcón, Hugo; López, Alcides; Candal, Roberto; Acosta, Dwight; Rodriguez, Juan

    2014-01-01

    Nanowire/nanorod TiO(2) structures of approximately 8 nm in diameter and around 1,000 nm long were synthesized by alkaline hydrothermal treatment of two different TiO(2) nanopowders. The first precursor was TiO(2) obtained by the sol-gel process (SG-TiO(2)); the second was the well-known commercial TiO(2) P-25 (P25-TiO(2)). Anatase-like 1D TiO(2) nanostructures were obtained in both cases. The one-dimensional (1D) nanostructures synthesized from SG-TiO(2) powders turned into rod-like nanostructures after annealing at 400 °C for 2 h. Conversely, the nanostructures synthesized from P25-TiO(2) preserved the tubular structure after annealing, displaying a higher Brunauer-Emmett-Teller surface area than the first system (279 and 97 m²/g, respectively). Despite the higher surface area shown by the 1D nanostructures, in both cases the photocatalytic activity was lower than for the P25-TiO(2) powder. However, the rod-like nanostructures obtained from SG-TiO(2) displayed slightly higher efficiency than the sol-gel prepared powders. The lower photocatalytic activity of the nanostructures with respect to P-25 can be associated with the lower crystallinity of 1D TiO(2) in both materials.

  17. The hippocampal CA2 region is essential for social memory.

    PubMed

    Hitti, Frederick L; Siegelbaum, Steven A

    2014-04-03

    The hippocampus is critical for encoding declarative memory, our repository of knowledge of who, what, where and when. Mnemonic information is processed in the hippocampus through several parallel routes involving distinct subregions. In the classic trisynaptic pathway, information proceeds from entorhinal cortex (EC) to dentate gyrus to CA3 and then to CA1, the main hippocampal output. Genetic lesions of EC (ref. 3) and hippocampal dentate gyrus (ref. 4), CA3 (ref. 5) and CA1 (ref. 6) regions have revealed their distinct functions in learning and memory. In contrast, little is known about the role of CA2, a relatively small area interposed between CA3 and CA1 that forms the nexus of a powerful disynaptic circuit linking EC input with CA1 output. Here we report a novel transgenic mouse line that enabled us to selectively examine the synaptic connections and behavioural role of the CA2 region in adult mice. Genetically targeted inactivation of CA2 pyramidal neurons caused a pronounced loss of social memory--the ability of an animal to remember a conspecific--with no change in sociability or several other hippocampus-dependent behaviours, including spatial and contextual memory. These behavioural and anatomical results thus reveal CA2 as a critical hub of sociocognitive memory processing.

  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. Density matrix spectra and order parameters in the 1D extended Hubbard model

    NASA Astrophysics Data System (ADS)

    Yu, Wing Chi; Gu, Shi-Jian; Lin, Hai-Qing

    2016-09-01

    Without any knowledge of the symmetry existing in a system, we derive the exact forms of the order parameters which show long-range correlations in the ground state of the one-dimensional (1D) extended Hubbard model using a quantum information approach. Our work demonstrates that the quantum information approach can help us to find the explicit form of the order parameter, which could not be derived systematically via traditional methods in the condensed matter theory.

  20. 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

  1. Low band gap frequencies and multiplexing properties in 1D and 2D mass spring structures

    NASA Astrophysics Data System (ADS)

    Aly, Arafa H.; Mehaney, Ahmed

    2016-11-01

    This study reports on the propagation of elastic waves in 1D and 2D mass spring structures. An analytical and computation model is presented for the 1D and 2D mass spring systems with different examples. An enhancement in the band gap values was obtained by modeling the structures to obtain low frequency band gaps at small dimensions. Additionally, the evolution of the band gap as a function of mass value is discussed. Special attention is devoted to the local resonance property in frequency ranges within the gaps in the band structure for the corresponding infinite periodic lattice in the 1D and 2D mass spring system. A linear defect formed of a row of specific masses produces an elastic waveguide that transmits at the narrow pass band frequency. The frequency of the waveguides can be selected by adjusting the mass and stiffness coefficients of the materials constituting the waveguide. Moreover, we pay more attention to analyze the wave multiplexer and DE-multiplexer in the 2D mass spring system. We show that two of these tunable waveguides with alternating materials can be employed to filter and separate specific frequencies from a broad band input signal. The presented simulation data is validated through comparison with the published research, and can be extended in the development of resonators and MEMS verification.

  2. ESO science data product standard for 1D spectral products

    NASA Astrophysics Data System (ADS)

    Micol, Alberto; Arnaboldi, Magda; Delmotte, Nausicaa A. R.; Mascetti, Laura; Retzlaff, Joerg

    2016-07-01

    The ESO Phase 3 process allows the upload, validation, storage, and publication of reduced data through the ESO Science Archive Facility. Since its introduction, 2 million data products have been archived and published; 80% of them are one-dimensional extracted and calibrated spectra. Central to Phase3 is the ESO science data product standard that defines metadata and data format of any product. This contribution describes the ESO data standard for 1d-spectra, its adoption by the reduction pipelines of selected instrument modes for in-house generation of reduced spectra, the enhanced archive legacy value. Archive usage statistics are provided.

  3. 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.

  4. Breakdown of 1D water wires inside charged carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Pant, Shashank

    2016-11-01

    Using molecular dynamics approach we investigated the structure and dynamics of water confined inside pristine and charged 6,6 carbon nanotubes (CNTs). This study reports the breakdown of 1D water wires and the emergence of triangular faced water on incorporating charges in 6,6 CNTs. Incorporation of charges results in high potential barriers to flipping of water molecules due to the formation of large number of hydrogen bonds. The PMF analyses show the presence of ∼2 kcal/mol barrier for the movement of water inside pristine CNT and almost negligible barrier in charged CNTs.

  5. Spatial coherence of polaritons in a 1D channel

    SciTech Connect

    Savenko, I. G.; Iorsh, I. V.; Kaliteevski, M. A.; Shelykh, I. A.

    2013-01-15

    We analyze time evolution of spatial coherence of a polariton ensemble in a quantum wire (1D channel) under constant uniform resonant pumping. Using the theoretical approach based on the Lindblad equation for a one-particle density matrix, which takes into account the polariton-phonon and excitonexciton interactions, we study the behavior of the first-order coherence function g{sup 1} for various pump intensities and temperatures in the range of 1-20 K. Bistability and hysteresis in the dependence of the first-order coherence function on the pump intensity is demonstrated.

  6. Nonlocal order parameters for the 1D Hubbard model.

    PubMed

    Montorsi, Arianna; Roncaglia, Marco

    2012-12-07

    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 U(c)=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 U(c). The behavior of the parity correlators is captured by an effective free spinless fermion model.

  7. 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.

  8. Nanofluidic sustainable energy conversion using a 1D nanofluidic network.

    PubMed

    Kim, Sang Hui; Kwak, Seungmin; Han, Sung Il; Chun, Dong Won; Lee, Kyu Hyoung; Kim, Jinseok; Lee, Jeong Hoon

    2014-05-01

    We propose a 1-dimensional (1D) nanofluidic energy conversion device by implementing a surface-patterned Nafion membrane for the direct energy conversion of the pressure to electrical power. By implementing a -200-nm-thick nano-bridge with a 5-nm pore size between two microfluidic channels, we acquired an effective streaming potential of 307 mV and output power of 94 pW with 0.1 mM KCI under pressure difference of 45 MPa. The experimental results show both the effects of applied pressure differences and buffer concentrations on the effective streaming potential, and are consistent with the analytical prediction.

  9. 1-D blood flow modelling in a running human body.

    PubMed

    Szabó, Viktor; Halász, Gábor

    2017-04-10

    In this paper an attempt was made to simulate blood flow in a mobile human arterial network, specifically, in a running human subject. In order to simulate the effect of motion, a previously published immobile 1-D model was modified by including an inertial force term into the momentum equation. To calculate inertial force, gait analysis was performed at different levels of speed. Our results show that motion has a significant effect on the amplitudes of the blood pressure and flow rate but the average values are not effected significantly.

  10. 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.

  11. Statistical mechanics of a one-component fluid of charged hard rods in 1D

    NASA Astrophysics Data System (ADS)

    Vericat, Fernando; Blum, Lesser

    1987-09-01

    The statistical mechanics of a classical one-component system of charged hard rods in a neutralizing background is investigated in 1D stressing on the effects of the hard-core interactions over the thermodynamics and the structure of the system. The crystalline status of the system at all temperatures and densities and the absence of phase transitions is shown by extending previous results of Baxter (1963) and Kunz (1974) on the one-component plasma of point particles. Explicit expressions for the thermodynamic functions and the one-particle correlation function are given in the limits of small and strong couplings.

  12. Tunability and Sensing Properties of Plasmonic/1D Photonic Crystal

    NASA Astrophysics Data System (ADS)

    Shaban, Mohamed; Ahmed, Ashour M.; Abdel-Rahman, Ehab; Hamdy, Hany

    2017-02-01

    Gold/one-dimensional photonic crystal (Au/1D-PC) is fabricated and applied for sensitive sensing of glucose and different chemical molecules of various refractive indices. The Au layer thickness is optimized to produce surface plasmon resonance (SPR) at the right edge of the photonic band gap (PBG). As the Au deposition time increased to 60 sec, the PBG width is increased from 46 to 86 nm in correlation with the behavior of the SPR. The selectivity of the optimized Au/1D-PC sensor is tested upon the increase of the environmental refractive index of the detected molecules. The resonance wavelength and the PBG edges increased linearly and the transmitted intensity increased nonlinearly as the environment refractive index increased. The SPR splits to two modes during the detection of chloroform molecules based on the localized capacitive coupling of Au particles. Also, this structure shows high sensitivity at different glucose concentrations. The PBG and SPR are shifted to longer wavelengths, and PBG width is decreased linearly with a rate of 16.04 Å/(μg/mm3) as the glucose concentration increased. The proposed structure merits; operation at room temperature, compact size, and easy fabrication; suggest that the proposed structure can be efficiently used for the biomedical and chemical application.

  13. Tunability and Sensing Properties of Plasmonic/1D Photonic Crystal

    PubMed Central

    Shaban, Mohamed; Ahmed, Ashour M.; Abdel-Rahman, Ehab; Hamdy, Hany

    2017-01-01

    Gold/one-dimensional photonic crystal (Au/1D-PC) is fabricated and applied for sensitive sensing of glucose and different chemical molecules of various refractive indices. The Au layer thickness is optimized to produce surface plasmon resonance (SPR) at the right edge of the photonic band gap (PBG). As the Au deposition time increased to 60 sec, the PBG width is increased from 46 to 86 nm in correlation with the behavior of the SPR. The selectivity of the optimized Au/1D-PC sensor is tested upon the increase of the environmental refractive index of the detected molecules. The resonance wavelength and the PBG edges increased linearly and the transmitted intensity increased nonlinearly as the environment refractive index increased. The SPR splits to two modes during the detection of chloroform molecules based on the localized capacitive coupling of Au particles. Also, this structure shows high sensitivity at different glucose concentrations. The PBG and SPR are shifted to longer wavelengths, and PBG width is decreased linearly with a rate of 16.04 Å/(μg/mm3) as the glucose concentration increased. The proposed structure merits; operation at room temperature, compact size, and easy fabrication; suggest that the proposed structure can be efficiently used for the biomedical and chemical application. PMID:28176799

  14. Tunability and Sensing Properties of Plasmonic/1D Photonic Crystal.

    PubMed

    Shaban, Mohamed; Ahmed, Ashour M; Abdel-Rahman, Ehab; Hamdy, Hany

    2017-02-08

    Gold/one-dimensional photonic crystal (Au/1D-PC) is fabricated and applied for sensitive sensing of glucose and different chemical molecules of various refractive indices. The Au layer thickness is optimized to produce surface plasmon resonance (SPR) at the right edge of the photonic band gap (PBG). As the Au deposition time increased to 60 sec, the PBG width is increased from 46 to 86 nm in correlation with the behavior of the SPR. The selectivity of the optimized Au/1D-PC sensor is tested upon the increase of the environmental refractive index of the detected molecules. The resonance wavelength and the PBG edges increased linearly and the transmitted intensity increased nonlinearly as the environment refractive index increased. The SPR splits to two modes during the detection of chloroform molecules based on the localized capacitive coupling of Au particles. Also, this structure shows high sensitivity at different glucose concentrations. The PBG and SPR are shifted to longer wavelengths, and PBG width is decreased linearly with a rate of 16.04 Å/(μg/mm(3)) as the glucose concentration increased. The proposed structure merits; operation at room temperature, compact size, and easy fabrication; suggest that the proposed structure can be efficiently used for the biomedical and chemical application.

  15. 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.

  16. Verification and comparison of four numerical schemes for a 1D viscoelastic blood flow model.

    PubMed

    Wang, Xiaofei; Fullana, Jose-Maria; Lagrée, Pierre-Yves

    2015-01-01

    A reliable and fast numerical scheme is crucial for the 1D simulation of blood flow in compliant vessels. In this paper, a 1D blood flow model is incorporated with a Kelvin-Voigt viscoelastic arterial wall. This leads to a nonlinear hyperbolic-parabolic system, which is then solved with four numerical schemes, namely: MacCormack, Taylor-Galerkin, monotonic upwind scheme for conservation law and local discontinuous Galerkin. The numerical schemes are tested on a single vessel, a simple bifurcation and a network with 55 arteries. The numerical solutions are checked favorably against analytical, semi-analytical solutions or clinical observations. Among the numerical schemes, comparisons are made in four important aspects: accuracy, ability to capture shock-like phenomena, computational speed and implementation complexity. The suitable conditions for the application of each scheme are discussed.

  17. Carbon Nanotubes for the Generation and Imaging of Interacting 1D States of Matter

    NASA Astrophysics Data System (ADS)

    Waissman, Jonah

    Low-dimensional systems in condensed matter physics exhibit a rich array of correlated electronic phases. One-dimensional systems stand out in this regard. Electrons cannot avoid each other in 1D, enhancing the effects of interactions. The resulting correlations leave distinct spatial imprints on the electronic density that can be imaged with scanning probes. Disorder, however, can destroy these delicate interacting states by breaking up the electron liquid into localized pieces. Thus, to generate fragile interacting quantum states, one requires an extremely clean system in which disorder does not overcome interactions, as well as a high degree of tunability to design potential landscapes. Furthermore, to directly measure the resulting spatial correlations, one requires an exceptionally sensitive scanning probe, but the most sensitive probes presently available are also invasive, perturbing the system and screening electron-electron interactions. In this thesis, we show how carbon nanotubes allow us to create pristine 1D electronic systems with unparalleled tunability. By realizing a new approach to device fabrication based on deterministic nano-assembly, we create devices of high complexity and low disorder by selectively attaching nanotubes of chosen bandgaps and cleanliness onto devices with large numbers of local gates. Using precision nano-assembly, we also demonstrate devices with multiple nanotubes placed at pre-determined locations. We then demonstrate the use of these devices as scanning charge detectors with the ability to image electrostatic potentials and to spatially resolve charging in a second nanotube device. By placing two such nanotube devices perpendicular to each other and bringing the two nanotubes into close proximity to each other, while distancing metal electrodes using our precise control over device geometry, we can use these devices as highly sensitive, high-resolution charge detectors that are also non-invasive. The capability to make

  18. Inhibition of CD1d-mediated antigen presentation by the transforming growth factor-β/Smad signalling pathway.

    PubMed

    Bailey, Jennifer C; Iyer, Abhirami K; Renukaradhya, Gourapura J; Lin, Yinling; Nguyen, Hoa; Brutkiewicz, Randy R

    2014-12-01

    CD1d-mediated lipid antigen presentation activates a subset of innate immune lymphocytes called invariant natural killer T (NKT) cells that, by virtue of their potent cytokine production, bridge the innate and adaptive immune systems. Transforming growth factor (TGF-β) is a known immune modulator that can activate the mitogen-activated protein kinase p38; we have previously shown that p38 is a negative regulator of CD1d-mediated antigen presentation. Several studies implicate a role for TGF-β in the activation of p38. Therefore, we hypothesized that TGF-β would impair antigen presentation by CD1d. Indeed, a dose-dependent decrease in CD1d-mediated antigen presentation and impairment of lipid antigen processing was observed in response to TGF-β treatment. However, it was found that this inhibition was not through p38 activation. Instead, Smads 2, 3 and 4, downstream elements of the TGF-β canonical signalling pathway, contributed to the observed effects. In marked contrast to that observed with CD1d, TGF-β was found to enhance MHC class II-mediated antigen presentation. Overall, these results suggest that the canonical TGF-β/Smad pathway negatively regulates an important arm of the host's innate immune responses - CD1d-mediated lipid antigen presentation to NKT cells.

  19. Functional CD1d and/or NKT cell invariant chain transcript in horse, pig, African elephant and guinea pig, but not in ruminants

    PubMed Central

    Looringh van Beeck, Frank A.; Reinink, Peter; Hermsen, Roel; Zajonc, Dirk M.; Laven, Marielle J.; Fun, Axel; Troskie, Milana; Schoemaker, Nico J.; Morar, Darshana; Lenstra, Johannes A.; Vervelde, Lonneke; Rutten, Victor P.M.G.; van Eden, Willem; Van Rhijn, Ildiko

    2009-01-01

    CD1d-restricted invariant natural killer T cells (NKT cells) have been well characterized in humans and mice, but it is unknown whether they are present in other species. Here we describe the invariant TCR α chain and the full length CD1d transcript of pig and horse. Molecular modeling predicts that porcine (po) invariant TCR α chain/poCD1d/α-GalCer and equine (eq) invariant TCR α chain/eqCD1d/α-GalCer form complexes that are highly homologous to the human complex. Since a prerequisite for the presence of NKT cells is the expression of CD1d protein, we performed searches for CD1D genes and CD1d transcripts in multiple species. Previously, cattle and guinea pig have been suggested to lack CD1D genes. The CD1D genes of European taurine cattle (Bos taurus) are known to be pseudogenes because of disrupting mutations in the start codon and in the donor splice site of the first intron. Here we show that the same mutations are found in six other ruminants: African buffalo, sheep, bushbuck, bongo, N’Dama cattle, and roe deer. In contrast, intact CD1d transcripts were found in guinea pig, African elephant, horse, rabbit, and pig. Despite the discovery of a highly homologous NKT/CD1d system in pig and horse, our data suggest that functional CD1D and CD1d-restricted NKT cells are not universally present in mammals. PMID:19185921

  20. 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.

  1. Statistical analysis of 1D HRR target features

    NASA Astrophysics Data System (ADS)

    Gross, David C.; Schmitz, James L.; Williams, Robert L.

    2000-08-01

    Automatic target recognition (ATR) and feature-aided tracking (FAT) algorithms that use one-dimensional (1-D) high range resolution (HRR) profiles require unique or distinguishable target features. This paper explores the use of statistical measures to quantify the separability and stability of ground target features found in HRR profiles. Measures of stability, such as the mean and variance, can be used to determine the stability of a target feature as a function of the target aspect and elevation angle. Statistical measures of feature predictability and separability, such as the Fisher and Bhattacharyya measures, demonstrate the capability to adequately predict the desired target feature over a specified aspect angular region. These statistical measures for separability and stability are explained in detail and their usefulness is demonstrated with measured HRR data.

  2. Axion string dynamics I: 2+1D

    SciTech Connect

    Fleury, Leesa M.; Moore, Guy D.

    2016-05-03

    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.

  3. 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.

  4. Evaluating 1d Seismic Models of the Lunar Interior

    NASA Astrophysics Data System (ADS)

    Yao, Y.; Thorne, M. S.; Weber, R. C.; Schmerr, N. C.

    2012-12-01

    A four station seismic network was established on the Moon from 1969 to 1977 as part of the Apollo Lunar Surface Experiment Package (ALSEP). A total of nine 1D seismic velocity models were generated using a variety of different techniques. In spite of the fact that these models were generated from the same data set, significant differences exist between them. We evaluate these models by comparing predicted travel-times to published catalogs of lunar events. We generate synthetic waveform predictions for 1D lunar models using a modified version of the Green's Function of the Earth by Minor Integration (GEMINI) technique. Our results demonstrate that the mean square errors between predicted and measured P-wave travel times are smaller than those for S-wave travel times in all cases. Moreover, models fit travel times for artificial and meteoroid impacts better than for shallow and deep moonquakes. Overall, models presented by Nakamura [Nakamura, 1983] and Garcia et al. [Garcia et al., 2011] predicted the observed travel times better than all other models and were comparable in their explanation of travel-times. Nevertheless, significant waveform differences exist between these models. In particular, the seismic velocity structure of the lunar crust and regolith strongly affect the waveform characteristics predicted by these models. Further complexity is added by possible mantle discontinuity structure that exists in a subset of these models. We show synthetic waveform predictions for these models demonstrating the role that crustal structure has in generating long duration seismic coda inherent in the lunar waveforms.

  5. 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.

  6. Quantitative 3D electromagnetic field determination of 1D nanostructures from single projection

    SciTech Connect

    Phatak, Charudatta; Knoop, Ludvig de; Houdellier, Florent; Gatel, Christophe; Hytch, Martin J.; Masseboeuf, Aurelien

    2016-03-10

    One-dimensional (1D) nanostructures have been regarded as the most promising building blocks for nanoelectronics and nanocomposite material systems as well as for alternative energy applications. Although they result in confinement of a material, their properties and interactions with other nanostructures are still very much three-dimensional (3D) in nature. In this work, we present a novel method for quantitative determination of the 3D electromagnetic fields in and around 1D nanostructures using a single electron wave phase image, thereby eliminating the cumbersome acquisition of tomographic data. Using symmetry arguments, we have reconstructed the 3D magnetic field of a nickel nanowire as well as the 3D electric field around a carbon nanotube field emitter, from one single projection. The accuracy of quantitative values determined here is shown to be a better fit to the physics at play than the value obtained by conventional analysis. Furthermore the 3D reconstructions can then directly be visualized and used in the design of functional 3D architectures built using 1D nanostructures.

  7. Quantitative 3D electromagnetic field determination of 1D nanostructures from single projection

    DOE PAGES

    Phatak, Charudatta; Knoop, Ludvig de; Houdellier, Florent; ...

    2016-03-10

    One-dimensional (1D) nanostructures have been regarded as the most promising building blocks for nanoelectronics and nanocomposite material systems as well as for alternative energy applications. Although they result in confinement of a material, their properties and interactions with other nanostructures are still very much three-dimensional (3D) in nature. In this work, we present a novel method for quantitative determination of the 3D electromagnetic fields in and around 1D nanostructures using a single electron wave phase image, thereby eliminating the cumbersome acquisition of tomographic data. Using symmetry arguments, we have reconstructed the 3D magnetic field of a nickel nanowire as wellmore » as the 3D electric field around a carbon nanotube field emitter, from one single projection. The accuracy of quantitative values determined here is shown to be a better fit to the physics at play than the value obtained by conventional analysis. Furthermore the 3D reconstructions can then directly be visualized and used in the design of functional 3D architectures built using 1D nanostructures.« less

  8. Quantitative 3D electromagnetic field determination of 1D nanostructures from single projection

    SciTech Connect

    Phatak, C.; Knoop, L. de; Houdellier, F.; Gatel, C.; Hÿtch, M. J.; Masseboeuf, A.

    2016-05-01

    One-dimensional (1D) nanostructures have been regarded as the most promising building blocks for nanoelectronics and nanocomposite material systems as well as for alternative energy applications. Although they result in confinement of a material, their properties and interactions with other nanostructures are still very much three-dimensional (3D) in nature. In this work, we present a novel method for quantitative determination of the 3D electromagnetic fields in and around 1D nanostructures using a single electron wave phase image, thereby eliminating the cumbersome acquisition of tomographic data. Using symmetry arguments, we have reconstructed the 3D magnetic field of a nickel nanowire as well as the 3D electric field around a carbon nanotube field emitter, from one single projection. The accuracy of quantitative values determined here is shown to be a better fit to the physics at play than the value obtained by conventional analysis. Moreover the 3D reconstructions can then directly be visualized and used in the design of functional 3D architectures built using 1D nanostructures.

  9. Lacunarity analysis of raster datasets and 1D, 2D, and 3D point patterns

    NASA Astrophysics Data System (ADS)

    Dong, Pinliang

    2009-10-01

    Spatial scale plays an important role in many fields. As a scale-dependent measure for spatial heterogeneity, lacunarity describes the distribution of gaps within a set at multiple scales. In Earth science, environmental science, and ecology, lacunarity has been increasingly used for multiscale modeling of spatial patterns. This paper presents the development and implementation of a geographic information system (GIS) software extension for lacunarity analysis of raster datasets and 1D, 2D, and 3D point patterns. Depending on the application requirement, lacunarity analysis can be performed in two modes: global mode or local mode. The extension works for: (1) binary (1-bit) and grey-scale datasets in any raster format supported by ArcGIS and (2) 1D, 2D, and 3D point datasets as shapefiles or geodatabase feature classes. For more effective measurement of lacunarity for different patterns or processes in raster datasets, the extension allows users to define an area of interest (AOI) in four different ways, including using a polygon in an existing feature layer. Additionally, directionality can be taken into account when grey-scale datasets are used for local lacunarity analysis. The methodology and graphical user interface (GUI) are described. The application of the extension is demonstrated using both simulated and real datasets, including Brodatz texture images, a Spaceborne Imaging Radar (SIR-C) image, simulated 1D points on a drainage network, and 3D random and clustered point patterns. The options of lacunarity analysis and the effects of polyline arrangement on lacunarity of 1D points are also discussed. Results from sample data suggest that the lacunarity analysis extension can be used for efficient modeling of spatial patterns at multiple scales.

  10. Low-field single-sided NMR for one-shot 1D-mapping: Application to membranes

    NASA Astrophysics Data System (ADS)

    Judeinstein, Patrick; Ferdeghini, Filippo; Oliveira-Silva, Rodrigo; Zanotti, Jean-Marc; Sakellariou, Dimitrios

    2017-04-01

    Many single-sided permanent magnet NMR systems have been proposed over the years allowing for 1D proton-density profiling, diffusion measurements and relaxometry. In this manuscript we make use of a recently published unilateral magnet for low-field NMR exhibiting an extremely uniform magnetic field gradient with moderate strength and cylindrical symmetry, allowing for a well-defined sweet spot. Combined with a goniometer, our system is used to characterize precisely the uniformity of its gradient and to achieve micrometric precision 1D profiling, as well as spatially localized relaxometry and diffusometry on thick (∼150 μm) membrane samples. Profiling with this magnet did not require repositioning of the samples with respect to the 1D tomograph.

  11. 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.

  12. 1-D Modeling of Massive Particle Injection (MPI) in Tokamaks

    NASA Astrophysics Data System (ADS)

    Wu, W.; Parks, P. B.; Izzo, V. A.

    2008-11-01

    A 1-D Fast Current Quench (FCQ) model is developed to study current evolution and runaway electron suppression under massive density increase. The model consists of coupled toroidal electric field and energy equations, and it is solved numerically for DIII-D and ITER operating conditions. Simulation results suggest that fast shutdown by D2 liquid jet/pellet injection is in principle achievable for the desired plasma cooling time (˜15 ms for DIII-D and ˜50 ms for ITER) under ˜150x or higher densification. The current density and pressure profile are practically unaltered during the initial phase of jet propagation when dilution cooling dominates. With subsequent radiation cooling, the densified discharge enters the strongly collisional regime where Pfirsch-Schluter thermal diffusion can inhibit current contraction on the magnetic axis. Often the 1/1 kink instability, addressed by Kadomtsev's magnetic reconnection model, can be prevented. Our results are compared with NIMROD simulations in which the plasma is suddenly densified by ˜100x and experiences instantaneous dilution cooling, allowing for use of actual (lower) Lundquist numbers.

  13. Energy eigenfunctions of the 1D Gross-Pitaevskii equation

    NASA Astrophysics Data System (ADS)

    Marojević, Želimir; Göklü, Ertan; Lämmerzahl, Claus

    2013-08-01

    We developed a new and powerful algorithm by which numerical solutions for excited states in a gravito-optical surface trap have been obtained. They represent solutions in the regime of strong nonlinearities of the Gross-Pitaevskii equation. In this context we also briefly review several approaches which allow, in principle, for calculating excited state solutions. It turns out that without modifications these are not applicable to strongly nonlinear Gross-Pitaevskii equations. The importance of studying excited states of Bose-Einstein condensates is also underlined by a recent experiment of Bücker et al. in which vibrational state inversion of a Bose-Einstein condensate has been achieved by transferring the entire population of the condensate to the first excited state. Here we focus on demonstrating the applicability of our algorithm for three different potentials by means of numerical results for the energy eigenstates and eigenvalues of the 1D Gross-Pitaevskii-equation. We compare the numerically found solutions and find out that they completely agree with the case of known analytical solutions.

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

    PubMed

    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 O(2) at 157 nm provides a clean source of fast-moving O((1)D(2)) 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.

  15. Cavitation Influence in 1D Part-load Vortex Models

    NASA Astrophysics Data System (ADS)

    Dörfler, P. K.

    2016-11-01

    Residual swirl in the draft tube of Francis turbines may cause annoying low- frequency pulsation of pressure and power output, in particular during part-load operation. A 1D analytical model for these dynamic phenomena would enable simulation by some conventional method for computing hydraulic transients. The proper structure of such a model has implications for the prediction of prototype behaviour based on laboratory tests. The source of excitation as well as the dynamic transmission behaviour of the draft tube flow may both be described either by lumped or distributed parameters. The distributed version contains more information and, due to limited possibilities of identification, some data must be estimated. The distributed cavitation compliance is an example for this dilemma. In recent publications, the customary assumption of a constant wave speed has produced dubious results. The paper presents a more realistic model for distributed compressibility. The measured influence of the Thoma number is applied with the local cavitation factor. This concept is less sensitive to modelling errors and explains both the Thoma and Froude number influence. The possible effect of the normally unknown non-condensable gas content in the vortex cavity is shortly commented. Its measurement in future tests is recommended. It is also recommended to check the available analytical vortex models for possible dispersion effects.

  16. Johnson-Nyquist Noise Coupling Formulation of Near-Field Heat Transfer for 1D Conductors

    NASA Astrophysics Data System (ADS)

    Prunnila, Mika; Laakso, Sampo; Gunnarsson, David

    Near-field heat transfer has been formulated using different levels of theoretical sophistication and complexity ranging from fluctuational electrodynamics to quasi-static Coulomb interaction description. Our goal is to find a simple description for the near-field heat transfer between coupled 1D electron systems (conductors). We will show that by considering distributed Johnson-Nyquist voltage sources, arising from the dissipative part of the electron systems' response, a compact fundamental formula for the near-field heat transfer can be found. We will describe the details of the derivation and discuss the regime of validity of our approach. Several special cases will be considered and experimental configurations will be discussed. The presented analysis is especially suitable for closely spaced graphene ribbons and nanowires. We will also show that by including inductive responses, which are necessary at high frequencies, speed of light emerges in the heat flow formula, thereby showing the link between fundamental physical quantities/constants and near-field heat transfer in coupled 1D systems. Our formulation also provides the possibility to use different boundary conditions for the physical system and this enables design of near-field heat transfer circuits.

  17. 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.

  18. Quantum Nucleation of Phase Slips in a 1D Model of a Superfluid

    SciTech Connect

    Freire, J.A.; Arovas, D.P.; Levine, H.

    1997-12-01

    We use a 1D model of a superfluid based on the Gross-Pitaevskii Lagrangian to illustrate a general numerical method designed to find quantum tunneling rates in extended bosonic systems. Specifically, we study flow past an obstacle and directly solve the imaginary time dynamics to find the {open_quotes}bounce{close_quotes} solution connected with the decay of the metastable laminar state via phase slip nucleation. The action for the tunneling configuration goes to zero at the threshold (in superfluid velocity) for classical production of these slips. Applications to other processes are briefly discussed. {copyright} {ital 1997} {ital The American Physical Society}

  19. Probing the Quantum State of a 1D Bose Gas Using Off-Resonant Light Scattering

    SciTech Connect

    Sykes, A. G.; Ballagh, R. J.

    2011-12-30

    We present a theoretical treatment of coherent light scattering from an interacting 1D Bose gas at finite temperatures. We show how this can provide a nondestructive measurement of the atomic system states. The equilibrium states are determined by the temperature and interaction strength, and are characterized by the spatial density-density correlation function. We show how this correlation function is encoded in the angular distribution of the fluctuations of the scattered light intensity, thus providing a sensitive, quantitative probe of the density-density correlation function and therefore the quantum state of the gas.

  20. 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.

  1. 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.

  2. 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

  3. Nonlinear electrical conductivity in a 1D granular medium

    NASA Astrophysics Data System (ADS)

    Falcon, E.; Castaing, B.; Creyssels, M.

    2004-04-01

    We report on observations of the electrical transport within a chain of metallic beads (slightly oxidized) under an applied stress. A transition from an insulating to a conductive state is observed as the applied current is increased. The voltage-current ( U- I) characteristics are nonlinear and hysteretic, and saturate to a low voltage per contact (0.4 V). Our 1D experiment allows us to understand phenomena (such as the “Branly effect”) related to this conduction transition by focusing on the nature of the contacts instead of the structure of the granular network. We show that this transition comes from an electro-thermal coupling in the vicinity of the microcontacts between each bead - the current flowing through these contact points generates their local heating which leads to an increase of their contact areas, and thus enhances their conduction. This current-induced temperature rise (up to 1050 ^{circ}C) results in the microsoldering of the contact points (even for voltages as low as 0.4 V). Based on this self-regulated temperature mechanism, an analytical expression for the nonlinear U- I back trajectory is derived, and is found to be in very good agreement with the experiments. In addition, we can determine the microcontact temperature with no adjustable parameters. Finally, the stress dependence of the resistance is found to be strongly non-hertzian due to the presence of the surface films. This dependence cannot be usually distinguished from the one due to the disorder of the granular contact network in 2D or 3D experiments.

  4. Restrained dark U (1 )d at low energies

    NASA Astrophysics Data System (ADS)

    Correia, Fagner C.; Fajfer, Svjetlana

    2016-12-01

    We investigate a spontaneously broken U (1 )d gauge symmetry with a muon-specific dark Higgs. Our first goal is to verify how the presence of a new dark Higgs, ϕ , and a dark gauge boson, V , can simultaneously face the anomalies from the muon magnetic moment and the proton charge radius. Second, by assuming that V must decay to an electron-positron pair, we explore the corresponding parameter space determined with the low-energy constraints coming from K →μ X , electron (g -2 )e, K →μ νμe+e-, K →μ νμμ+μ-, and τ →ντμ νμe+e-. We focus on the scenario where the V mass is below ˜2 mμ and the ϕ mass runs from few MeV to 250 MeV, with V -photon mixing of the order ˜O (10-3). Among weak process at low energies, we check the influence of the new light vector on kaon decays as well as on the scattering e+e-→μ+μ-e+e- and discuss the impact of the dark Higgs on e+e-→μ+μ-μ+μ-. Finally, we consider contributions of the V -photon mixing in the decays π0→γ e+e-, η →γ e+e-, ρ →π e+e-, K*→K e+e-, and ϕ (1020 )→η e+e-.

  5. A new general 1-D vadose zone flow solution method

    NASA Astrophysics Data System (ADS)

    Ogden, Fred L.; Lai, Wencong; Steinke, Robert C.; Zhu, Jianting; Talbot, Cary A.; Wilson, John L.

    2015-06-01

    We have developed an alternative to the one-dimensional partial differential equation (PDE) attributed to Richards (1931) that describes unsaturated porous media flow in homogeneous soil layers. Our solution is a set of three ordinary differential equations (ODEs) derived from unsaturated flux and mass conservation principles. We used a hodograph transformation, the Method of Lines, and a finite water-content discretization to produce ODEs that accurately simulate infiltration, falling slugs, and groundwater table dynamic effects on vadose zone fluxes. This formulation, which we refer to as "finite water-content", simulates sharp fronts and is guaranteed to conserve mass using a finite-volume solution. Our ODE solution method is explicitly integrable, does not require iterations and therefore has no convergence limits and is computationally efficient. The method accepts boundary fluxes including arbitrary precipitation, bare soil evaporation, and evapotranspiration. The method can simulate heterogeneous soils using layers. Results are presented in terms of fluxes and water content profiles. Comparing our method against analytical solutions, laboratory data, and the Hydrus-1D solver, we find that predictive performance of our finite water-content ODE method is comparable to or in some cases exceeds that of the solution of Richards' equation, with or without a shallow water table. The presented ODE method is transformative in that it offers accuracy comparable to the Richards (1931) PDE numerical solution, without the numerical complexity, in a form that is robust, continuous, and suitable for use in large watershed and land-atmosphere simulation models, including regional-scale models of coupled climate and hydrology.

  6. Modeling shear band interaction in 1D torsion

    NASA Astrophysics Data System (ADS)

    Partom, Yehuda; Hanina, Erez

    2017-01-01

    When two shear bands are being formed at close distance from each other they interact, and further development of one of them may be quenched down. As a result there should be a minimum distance between shear bands. In the literature there are at least three analytical models for this minimum distance. Predictions of these models do not generally agree with each other and with test results. Recently we developed a 1D numerical scheme to predict the formation of shear bands in a torsion test of a thin walled pipe. We validated our code by reproducing results of the pioneering experiments of Marchand and Duffy, and then used it to investigate the mechanics of shear localization and shear band formation. We describe our shear band code in a separate publication, and here we use it only as a tool to investigate the interaction between two neighboring shear bands during the process of their formation. We trigger the formation of shear bands by specifying two perturbations of the initial strength. We vary the perturbations in terms of their amplitude and/or their width. Usually, the stronger perturbation triggers a faster developing shear band, which then prevails and quenches the development of the other shear band. We change the distance between the two shear bands and find, that up to a certain distance one of the shear bands becomes fully developed, and the other stays only partially developed. Beyond this distance the two shear bands are both fully developed. Finally, we check the influence of certain material and loading parameters on the interaction between the two shear bands, and compare the results to predictions of the analytical models from the literature.

  7. 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

  8. Resolution-optimized NMR measurement of (1)D(CH), (1)D(CC) and (2)D(CH) residual dipolar couplings in nucleic acid bases.

    PubMed

    Boisbouvier, Jérôme; Bryce, David L; O'neil-Cabello, Erin; Nikonowicz, Edward P; Bax, Ad

    2004-11-01

    New methods are described for accurate measurement of multiple residual dipolar couplings in nucleic acid bases. The methods use TROSY-type pulse sequences for optimizing resolution and sensitivity, and rely on the E.COSY principle to measure the relatively small two-bond (2)D(CH) couplings at high precision. Measurements are demonstrated for a 24-nt stem-loop RNA sequence, uniformly enriched in (13)C, and aligned in Pf1. The recently described pseudo-3D method is used to provide homonuclear (1)H-(1)H decoupling, which minimizes cross-correlation effects and optimizes resolution. Up to seven (1)H-(13)C and (13)C-(13)C couplings are measured for pyrimidines (U and C), including (1)D(C5H5), (1)D(C6H6), (2)D(C5H6), (2)D(C6H5), (1)D(C5C4), (1)D(C5C6), and (2)D(C4H5). For adenine, four base couplings ((1)D(C2H2), (1)D(C8H8), (1)D(C4C5), and (1)D(C5C6)) are readily measured whereas for guanine only three couplings are accessible at high relative accuracy ((1)D(C8H8), (1)D(C4C5), and (1)D(C5C6)). Only three dipolar couplings are linearly independent in planar structures such as nucleic acid bases, permitting cross validation of the data and evaluation of their accuracies. For the vast majority of dipolar couplings, the error is found to be less than +/-3% of their possible range, indicating that the measurement accuracy is not limiting when using these couplings as restraints in structure calculations. Reported isotropic values of the one- and two-bond J couplings cluster very tightly for each type of nucleotide.

  9. Engineering 1D Quantum Stripes from Superlattices of 2D Layered Materials.

    PubMed

    Gruenewald, John H; Kim, Jungho; Kim, Heung Sik; Johnson, Jared M; Hwang, Jinwoo; Souri, Maryam; Terzic, Jasminka; Chang, Seo Hyoung; Said, Ayman; Brill, Joseph W; Cao, Gang; Kee, Hae-Young; Seo, Sung S Ambrose

    2017-01-01

    Dimensional tunability from two dimensions to one dimension is demonstrated for the first time using an artificial superlattice method in synthesizing 1D stripes from 2D layered materials. The 1D confinement of layered Sr2 IrO4 induces distinct 1D quantum-confined electronic states, as observed from optical spectroscopy and resonant inelastic X-ray scattering. This 1D superlattice approach is generalizable to a wide range of layered materials.

  10. GNSS meteorology for severe weather - 1D, 2D and 3D solution

    NASA Astrophysics Data System (ADS)

    Rohm, Witold; Manning, Toby; Yuan, Yubin; Biadeglgne, Bertukan; Choy, Sue Lynn; Zhang, Kefei

    2013-04-01

    The variability of water vapour (WV) is strongly correlated with the formation, course and dissipation of the mesoscale convective storm systems, due to the large latent heat transfers in the evaporation/condensation process. Contrary to its importance WV space and time distribution remains under sampled in both domains, especially in sparsely populated countries such as Australia. GPS meteorology currently is a very important data source for meteorology, climatology and forecasting, due to the relatively dense network of receivers, operating in the unified reference frame. Point observations of troposphere delay (1D), integrated water vapour (1D), as well as maps of these parameters (2D) are highly sensitive to building up of high amount of water vapour in the troposphere, as well as storm passage. The Kalman filter based GNSS tomography is an emerging method of reconstructing dynamically changing wet refractivity fields (3D). All types of ground based GNSS products has solid scientific foundations and are routinely estimated by major GNSS processing centres with high accuracy and low latency (ie. EGVAP AC). The forthcoming challenge of for the analyse of GNSS meteorology estimates (1D, 2D and 3D) is developing a quantifiable method to predict as well as identify location, size and severity of mesoscale convective storm system. In the course of this research several spatial and temporal filter and indicators have been developed to aid in early detection, prediction and monitoring of severe weather events using all types of GNSS meteorology by-products estimates (1D, 2D and 3D). This research presents a case study based on the analysis of an extreme convective super cell storm in the Victorian region during March 2010 using GPS tomography. Integrated Perceptible Water readings collected from MOBS stations confirmed high time resolution as well as sensitivity to incoming severe weather. Another, special measure of Refractive Index adopted for GPS tomography wet

  11. 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.

  12. 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).

  13. Preliminary abatement device evaluation: 1D-2D KGM cyclone design

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cyclones are predominately used in controlling cotton gin particulate matter (PM) emissions. The most commonly used cyclone designs are the 2D-2D and 1D-3D; however other designs such as the 1D-2D KGM have or are currently being used. A 1D-2D cyclone has a barrel length equal to the barrel diamete...

  14. Large Area Synthesis of 1D-MoSe2 Using Molecular Beam Epitaxy.

    PubMed

    Poh, Sock Mui; Tan, Sherman J R; Zhao, Xiaoxu; Chen, Zhongxin; Abdelwahab, Ibrahim; Fu, Deyi; Xu, Hai; Bao, Yang; Zhou, Wu; Loh, Kian Ping

    2017-01-23

    Large area synthesis of 1D-MoSe2 nanoribbons on both insulating and conducting substrates via molecular beam epitaxy is presented. Dimensional controlled growth of 2D, 1D-MoSe2 , and 1D-2D-MoSe2 hybrid heterostructure is achieved by tuning the growth temperature or Mo:Se precursor ratio.

  15. PPM1D exerts its oncogenic properties in human pancreatic cancer through multiple mechanisms.

    PubMed

    Wu, Bo; Guo, Bo-Min; Kang, Jie; Deng, Xian-Zhao; Fan, You-Ben; Zhang, Xiao-Ping; Ai, Kai-Xing

    2016-03-01

    Protein phosphatase, Mg(2+)/Mn(2+) dependent, 1D (PPM1D) is emerging as an oncogene by virtue of its negative control on several tumor suppressor pathways. However, the clinical significance of PPM1D in pancreatic cancer (PC) has not been defined. In this study, we determined PPM1D expression in human PC tissues and cell lines and their irrespective noncancerous controls. We subsequently investigated the functional role of PPM1D in the migration, invasion, and apoptosis of MIA PaCa-2 and PANC-1 PC cells in vitro and explored the signaling pathways involved. Furthermore, we examined the role of PPM1D in PC tumorigenesis in vivo. Our results showed that PPM1D is overexpressed in human PC tissues and cell lines and significantly correlated with tumor growth and metastasis. PPM1D promotes PC cell migration and invasion via potentiation of the Wnt/β-catenin pathway through downregulation of apoptosis-stimulating of p53 protein 2 (ASPP2). In contrast to PPM1D, our results showed that ASPP2 is downregulated in PC tissues. Additionally, PPM1D suppresses PC cell apoptosis via inhibition of the p38 MAPK/p53 pathway through both dephosphorylation of p38 MAPK and downregulation of ASPP2. Furthermore, PPM1D promotes PC tumor growth in vivo. Our results demonstrated that PPM1D is an oncogene in PC.

  16. 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

  17. 5-HT1D receptor inhibits renal sympathetic neurotransmission by nitric oxide pathway in anesthetized rats.

    PubMed

    García-Pedraza, José-Ángel; García, Mónica; Martín, María-Luisa; Morán, Asunción

    2015-09-01

    Although serotonin has been shown to inhibit peripheral sympathetic outflow, serotonin regulation on renal sympathetic outflow has not yet been elucidated. This study investigated which 5-HT receptor subtypes are involved. Wistar rats were anesthetized (sodium pentobarbital; 60mg/kg, i.p.), and prepared for in situ autoperfused rat kidney, which allows continuous measurement of systemic blood pressure (SBP), heart rate (HR) and renal perfusion pressure (PP). Electrical stimulation of renal sympathetic nerves resulted in frequency-dependent increases in PP (18.3±1.0, 43.7±2.7 and 66.7±4.0 for 2, 4 and 6Hz, respectively), without altering SBP or HR. 5-HT, 5-carboxamidotryptamine (5-HT1/7 agonist) (0.00000125-0.1μg/kg each) or l-694,247 (5-HT1D agonist; 0.0125μg/kg) i.a. bolus inhibited vasopressor responses by renal nerve electrical stimulation, unlike i.a. bolus of agonists α-methyl-5-HT (5-HT2), 1-PBG (5-HT3), cisapride (5-HT4), AS-19 (5-HT7), CGS-12066B (5-HT1B) or 8-OH-DPAT (5-HT1A) (0.0125μg/kg each). The effect of l-694,247 did not affect the exogenous norepinephrine-induced vasoconstrictions, whereas was abolished by antagonist LY310762 (5-HT1D; 1mg/kg) or l-NAME (nitric oxide; 10mg/kg), but not by indomethacin (COX1/2; 2mg/kg) or glibenclamide (ATP-dependent K(+) channel; 20mg/kg). These results suggest that 5-HT mechanism-induced inhibition of rat vasopressor renal sympathetic outflow is mainly mediated by prejunctional 5-HT1D receptors via nitric oxide release.

  18. Electrochemical cortisol immunosensors based on sonochemically synthesized zinc oxide 1D nanorods and 2D nanoflakes.

    PubMed

    Vabbina, Phani Kiran; Kaushik, Ajeet; Pokhrel, Nimesh; Bhansali, Shekhar; Pala, Nezih

    2015-01-15

    We report on label free, highly sensitive and selective electrochemical immunosensors based on one-dimensional 1D ZnO nanorods (ZnO-NRs) and two-dimensional 2D ZnO nanoflakes (ZnO-NFs) which were synthesized on Au-coated substrates using simple one step sonochemical approach. Selective detection of cortisol using cyclic voltammetry (CV) is achieved by immobilizing anti-cortisol antibody (Anti-C(ab)) on the ZnO nanostructures (NSs). 1D ZnO-NRs and 2D ZnO-NFs provide unique sensing advantages over bulk materials. While 1D-NSs boast a high surface area to volume ratio, 2D-NSs with large area in polarized (0001) plane and high surface charge density could promote higher Anti-C(ab) loading and thus better sensing performance. Beside large surface area, ZnO-NSs also exhibit higher chemical stability, high catalytic activity, and biocompatibility. TEM studies showed that both ZnO-NSs are single crystalline oriented in (0001) plane. The measured sensing parameters are in the physiological range with a sensitivity of 11.86 µA/M exhibited by ZnO-NRs and 7.74 µA/M by ZnO-NFs with the lowest detection limit of 1 pM which is 100 times better than conventional enzyme-linked immunosorbant immunoassay (ELISA). ZnO-NSs based cortisol immunosensors were tested on human saliva samples and the performance were validated with conventional (ELISA) method which exhibits a remarkable correlation. The developed sensors can be integrated with microfluidic system and miniaturized potentiostat for point-of-care cortisol detection and such developed protocol can be used in personalized health monitoring/diagnostic.

  19. Natural Outbreak of BVDV-1d-Induced Mucosal Disease Lacking Intestinal Lesions.

    PubMed

    Bianchi, M V; Konradt, G; de Souza, S O; Bassuino, D M; Silveira, S; Mósena, A C S; Canal, C W; Pavarini, S P; Driemeier, D

    2017-03-01

    Bovine viral diarrhea virus (BVDV) belongs to the Pestivirus genus, which is further divided into subgenotypes (1a-1u and 2a-c). When persistent infection occurs, the calf will be immunotolerant to BVDV and possibly develop mucosal disease. This study describes an outbreak of BVDV-1d-induced mucosal disease lacking intestinal lesions. Eleven calves presented with anorexia, sialorrhea, lameness, recumbency, and death. Three calves were necropsied, showing ulceration of the interdigital skin and the oral and nasal mucosa; linear ulcers in the tongue, esophagus, and rumen; and rounded ulcers in the abomasum. Microscopically, mucosa and skin had superficial necrosis, with single-cell necrosis and vacuolation in epithelial cells, and severe parakeratosis. Immunohistochemistry (IHC) showed BVDV antigen in the cytoplasm of epithelial cells in skin and mucosa. All 11 dead calves were positive upon reverse transcription-polymerase chain reaction (RT-PCR) for the detection of Pestivirus along with another 11 live calves from the herd, which were positive again by RT-PCR and IHC after a 4-week interval. Sequencing of the 5' untranslated region and N-terminal protease showed that viruses from these 22 calves were homologous and of subgenotype BVDV-1d. Cytopathic BVDV was isolated from 8 of 11 dead calves, but only noncytopathic BVDV was isolated from the 11 live animals. The findings indicate that this was an outbreak of mucosal disease caused by BVDV-1d, with high morbidity, and lesions restricted to the upper alimentary system and skin and absent from intestine. Thus, the epidemiological and pathological features in this form of mucosal disease may be similar to vesicular diseases, including foot and mouth disease.

  20. Advanced Fuel Cycle Initiative AFC-1D, AFC-1G and AFC-1H Irradiation Report

    SciTech Connect

    Debra J. Utterbeck; Gray Chang

    2005-09-01

    The U. S. Advanced Fuel Cycle Initiative (AFCI) seeks to develop and demonstrate the technologies needed to transmute the long-lived transuranic actinide isotopes contained in spent nuclear fuel into shorter-lived fission products, thereby dramatically decreasing the volume of material requiring disposition and the long-term radiotoxity and heat load of high-level waste sent to a geologic repository. The AFC-1 irradiation experiments on transmutation fuels are expected to provide irradiation performance data on non-fertile and low-fertile fuel forms specifically, irradiation growth and swelling, helium production, fission gas release, fission product and fuel constituent migration, fuel phase equilibria, and fuel-cladding chemical interaction. Contained in this report are the to-date physics evaluations performed on three of the AFC-1 experiments; AFC-1D, AFC-1G and AFC-1H. The AFC-1D irradiation experiment consists of metallic non-fertile fuel compositions with minor actinides for potential use in accelerator driven systems and AFC-1G and AFC-1H irradiation experiments are part of the fast neutron reactor fuel development effort. These experiments are high burnup analogs to previously irradiated experiments and are to be irradiated to = 20 atom % burnup. Results of the evaluations show that AFC-1D will remain in the ATR for approximately 100 additional effective full power days (EFPDs), and AFC-1G and AFC-1H for approximately 300 additional EFPDs in order to reach the desired programmatic burnup. The specific irradiation schedule for these tests will be determined based on future physics evaluations and all results will be documented in subsequent reports.

  1. Hot Gas in SMC SNR 0057-7226 and the Giant H 2 Region N66

    NASA Astrophysics Data System (ADS)

    Danforth, C. W.; Hoopes, C. G.; Sankrit, R.; Chu, Y.-H.; Sembach, K. R.; Blair, W. P.

    2001-12-01

    The supernova remnant SNR 0057-7226 and the dense, young cluster NGC 346 lie within the giant H 2 region N66, the most active star formation site in the SMC. Far Ultraviolet Spectroscopic Explorer (FUSE) observations of the Wolf-Rayet binary system HD 5980, which lies behind the SNR, show high velocity, O 6 and C 3 absorption associated with the far side of the remnant (Hoopes et al 2001, ApJ, 558, L35). Chandra ACIS-I and ROSAT HRI images of N66 show the diffuse X-ray emission associated with the SNR, but little or no diffuse emission around the core of the central cluster. We present high-dispersion, long-slit optical echelle observations of five positions within N66 including positions across the SNR 0057-7226 and NGC 346. These data show bright Hα emission at the SMC rest velocity (v ~155 km s-1). Where the spectrograph slits intersect the SNR, faint Hα emission at high (v ~300 km s-1) and low (v ~50 km s-1) velocities reveals clumps of material on the back and front sides of the SNR shell. Ten FUSE observations of sight lines toward stars in N66--including four toward NGC 346 cluster stars--provide sensitive absorption-line measurements of several ionic species including O 6 which traces hot (T ~3*E5 K), highly-ionized gas and Fe 2 which traces cooler (T ~104 K), ionized and neutral gas. We also present ground based optical narrowband images in Hα , [S 2], and [O 3] which show the morphology of the H 2 region. We use this data set to study the kinematics of the gas in this complex region and to model the properties of the SNR-ISM interaction. This work is supported by NASA Contract NAS5-32985 to the Johns Hopkins University.

  2. Rational design of D-A1-D-A2 conjugated polymers with superior spectral coverage.

    PubMed

    Hedström, Svante; Tao, Qiang; Wang, Ergang; Persson, Petter

    2015-10-28

    The spectral coverage of a light-harvesting polymer largely determines the maximum achievable photocurrent in organic photovoltaics, and therefore constitutes a crucial parameter for improving their performance. The D-A1-D-A2 copolymer motif is a new and promising design strategy for extending the absorption range by incorporating two acceptor units with complementary photoresponses. The fundamental factors that promote an extended absorption are here determined for three prototype D-A1-D-A2 systems through a combination of experimental and computational methods. Systematic quantum chemical calculations are then used to reveal the intrinsic optical properties of ten further D-A1-D-A2 polymer candidates. These investigated polymers are all predicted to exhibit intense primary absorption peaks at 615-954 nm, corresponding to charge-transfer (CT) transitions to the stronger acceptor, as well as secondary absorption features at 444-647 nm that originate from CT transitions to the weaker acceptors. Realization of D-A1-D-A2 polymers with superior spectral coverage is thereby found to depend critically on the spatial and energetic separation between the two distinct acceptor LUMOs. Two promising D-A1-D-A2 copolymer candidates were finally selected for further theoretical and experimental study, and demonstrate superior light-harvesting properties in terms of significantly extended spectral coverage. This demonstrates great potential for enhanced light-harvesting in D-A1-D-A2 polymers via multiple absorption features compared to traditional D-A polymers.

  3. Analysis of the rotational structure in the high-resolution infrared spectra of trans-hexatriene-1,1-d2 and -cis-1-d1

    NASA Astrophysics Data System (ADS)

    Craig, Norman C.; Fuson, Hannah A.; Tian, Hengfeng; Blake, Thomas A.

    2012-09-01

    Mixtures of trans-hexatriene-1,1-d2, -cis-1-d1, and -trans-1-d1 have been synthesized. Anharmonic frequencies and harmonic intensities were predicted with the B3LYP/cc-pVTZ model for the out-of-plane (a″) modes of the three isotopologues. Assignments are proposed for most of the a″ vibrational modes above 500 cm-1. Ground state (GS) rotational constants have been determined for the 1,1-d2 and cis-1-d1 species from the analysis of rotational structure of C-type bands in the high-resolution (0.0015 cm-1) infrared spectra in a mixture of the three isotopologues. The GS constants for the 1,1-d2 species are A0 = 0.8018850(6), B0 = 0.0418540(6), and C0 = 0.0397997(4) cm-1. The GS constants for the cis-1-d1 species are A0 = 0.809388(1), B0 = 0.043532(2), and C0 = 0.041320(1) cm-1. Small inertial defects confirm planarity for both species. These ground state rotational constants are intended for use in determining a semiexperimental equilibrium structure and evaluating the influence of chain length on π-electron delocalization in polyenes.

  4. From 2D graphene to 1D graphene nanoribbons: dimensional crossover signals in the structural thermal fluctuations

    NASA Astrophysics Data System (ADS)

    Dobry, Ariel; Costamagna, Sebastián

    2011-03-01

    I this work, by analyzing the thermal excited rippling in the graphene honeycomb lattice, we find clear signals of an existing dimensional crossover from 2D to 1D while reducing one of the dimensions of the graphene layer. Trough a joint study, using montecarlo atomistic simulations and analytical calculation based, we find that the normal-normal correlation function G (q) does not change the power law behavior valid on the long wavelength limit, however the system size dependency of the quadratic out of plane displacement h2 shows a breakdown of its corresponding scaling law. In this case we show that a new scaling law appear which correspond to a truly 1D system. On the basis of these results, and having explored a wide number of realistic systems size, we conclude that narrow nanoribbons presents strongest corrugations than the square graphene sheets. This result could have important consequences on the electron transport properties of freestanding graphene systems.

  5. Dendritic cell recognition using template matching based on one-dimensional (1D) Fourier descriptors (FD)

    NASA Astrophysics Data System (ADS)

    Muhd Suberi, Anis Azwani; Wan Zakaria, Wan Nurshazwani; Tomari, Razali; Lau, Mei Xia

    2016-07-01

    Identification of Dendritic Cell (DC) particularly in the cancer microenvironment is a unique disclosure since fighting tumor from the harnessing immune system has been a novel treatment under investigation. Nowadays, the staining procedure in sorting DC can affect their viability. In this paper, a computer aided system is proposed for automatic classification of DC in peripheral blood mononuclear cell (PBMC) images. Initially, the images undergo a few steps in preprocessing to remove uneven illumination and artifacts around the cells. In segmentation, morphological operators and Canny edge are implemented to isolate the cell shapes and extract the contours. Following that, information from the contours are extracted based on Fourier descriptors, derived from one dimensional (1D) shape signatures. Eventually, cells are classified as DC by comparing template matching (TM) of established template and target images. The results show that the proposed scheme is reliable and effective to recognize DC.

  6. 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

  7. 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.

  8. Self-assembled 1D magnetic Ising chains: epitaxial islands of Co/Ru(0001)

    NASA Astrophysics Data System (ADS)

    Li, Dongqi; Yu, Chengtao; Pearson, John; Bader, Samuel

    2002-03-01

    We have self-assembled magnetic Co dot chains via epitaxial island decoration of grooved Ru(0001) to create a model 1D system. Co wedge-like structures of 0-60 nm thick were deposited onto flat and grooved Ru(0001) substrates via molecular beam epitaxy at 350¢ªC and characterized ex-situ with atomic force and the magnetic force microscopy (MFM), and magneto-optic Kerr effect. The grooved substrate has a saw-tooth profile with spacing of order of 1 um, due to residual polishing scratches / step bunching. Co forms strain-induced, quasi-hexagonal dots of 70-500 nm in diameter and 1-20 nm high, depending on nominal dosage. On grooved substrate, the dots self align into chains along the groove near the top and bottom of the saw-tooth structure.[1] The dots are ferromagnetically coupled along the chain and exhibit magnetic single-domains with in-plane uniaxial anisotropy along the grooves. The inter-dot magnetic pair correlation was deduced from the MFM images of the dot-chains, and can be understood in terms of the classic 1D Ising model. * Work supported by DOE BES-MS under #W-31-109-ENG-38. 1. Chengtao Yu, Dongqi Li, J. Pearson, and S.D. Bader, Appl. Phys. Lett. 78, 1228 (2001); ibid. 79, 3848 (2001).

  9. 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.

  10. Pullback, forward and chaotic dynamics in 1D non-autonomous linear-dissipative equations

    NASA Astrophysics Data System (ADS)

    Caraballo, T.; Langa, J. A.; Obaya, R.

    2017-01-01

    The global attractor of a skew product semiflow for a non-autonomous differential equation describes the asymptotic behaviour of the model. This attractor is usually characterized as the union, for all the parameters in the base space, of the associated cocycle attractors in the product space. The continuity of the cocycle attractor in the parameter is usually a difficult question. In this paper we develop in detail a 1D non-autonomous linear differential equation and show the richness of non-autonomous dynamics by focusing on the continuity, characterization and chaotic dynamics of the cocycle attractors. In particular, we analyse the sets of continuity and discontinuity for the parameter of the attractors, and relate them with the eventually forward behaviour of the processes. We will also find chaotic behaviour on the attractors in the Li-Yorke and Auslander-Yorke senses. Note that they hold for linear 1D equations, which shows a crucial difference with respect to the presence of chaotic dynamics in autonomous systems.

  11. A multiple digital watermarking algorithm based on 1D and 2D chaotic sequences

    NASA Astrophysics Data System (ADS)

    Ji, Zhen; Jiang, Lai; Jin, Jing; Zhang, Jihong

    2003-09-01

    Multiple digital watermarking is attracting more and more researchers because it is more valuable in the practical applications than single watermarking. In this paper, a multiple watermarking algorithm based on 1-D and 2-D chaotic sequences is proposed. The chaotic sequences have the advantages of massive, high security, and weakest correlation. The massive and independent digital watermark signals are generated through 1-D chaotic maps, which are determined by different initial conditions and parameters. The chaotic digital watermark signals effectively resolve the construction of massive watermarks with good performance. The embedding of multiple watermakrs is more complex than the single watermarking scheme. In this paper, each watermark is added to the middle frequency coefficients of wavelet domain randomly by exploiting 2-D chaotic system, so the embedding and extracting of each watermark would not disturb each other. Considering the parameters of 2-D chaotic systsem as the key to embedding procedure can prevent the watermarks to be removed maliciously, therefore the performance of security is better. The capacity of the multiple watermarking is also analyzed in this paper. The experimental results demonstrate that this proposed watermarking algorithm is robust to many common attacks and it is a reliable copyright protection for multiple legal owners.

  12. 1D quantum simulation using a solid state platform

    NASA Astrophysics Data System (ADS)

    Kirkendall, Megan; Irvin, Patrick; Huang, Mengchen; Levy, Jeremy; Lee, Hyungwoo; Eom, Chang-Beom

    Understanding the properties of large quantum systems can be challenging both theoretically and numerically. One experimental approach-quantum simulation-involves mapping a quantum system of interest onto a physical system that is programmable and experimentally accessible. A tremendous amount of work has been performed with quantum simulators formed from optical lattices; by contrast, solid-state platforms have had only limited success. Our experimental approach to quantum simulation takes advantage of nanoscale control of a metal-insulator transition at the interface between two insulating complex oxide materials. This system naturally exhibits a wide variety of ground states (e.g., ferromagnetic, superconducting) and can be configured into a variety of complex geometries. We will describe initial experiments that explore the magnetotransport properties of one-dimensional superlattices with spatial periods as small as 4 nm, comparable to the Fermi wavelength. The results demonstrate the potential of this solid-state quantum simulation approach, and also provide empirical constraints for physical models that describe the underlying oxide material properties. We gratefully acknowledge financial support from AFOSR (FA9550-12-1- 0057 (JL), FA9550-10-1-0524 (JL) and FA9550-12-1-0342 (CBE)), ONR N00014-15-1-2847 (JL), and NSF DMR-1234096 (CBE).

  13. XPB Induces C1D Expression to Counteract UV-Induced Apoptosis

    PubMed Central

    Li, Guang; Liu, Juhong; Abu-Asab, Mones; Masabumi, Shibuya; Maru, Yoshiro

    2010-01-01

    Although C1D has been shown to be involved in DNA double-strand breaks repair, how C1D expression was induced and the mechanism(s) by which C1D facilitates DNA repair in mammalian cells remain poorly understood. We and others have previously shown that expression of XPB protein efficiently compensated the UV-irradiation sensitive phenotype of 27-1 cells which lacks functional XPB. To further explore XPB-regulated genes that could be involved in UV-induced DNA repair, Differential Display analysis of mRNA level from CHO-9, 27-1 and 27-1 complemented with wild-type XPB were performed and C1D gene was identified as one of the major genes whose expression was significantly up-regulated by restoring XPB function. We found that XPB is essential to induce C1D transcription after UV-irradiation. The increase of C1D expression effectively compensates the UV-induced proteolysis of C1D and thus maintains cellular C1D level to cope with DNA damage inflicted by UV-irradiation. We further showed that although insufficient to rescue 27-1 cells from UV-induced apoptosis by itself, C1D facilitates XPB DNA repair through direct interaction with XPB. Our findings provided direct evidence that C1D is associated with DNA repair complex and may promote repair of UV-induced DNA damage. PMID:20530579

  14. Quasi 1D Modeling of Mixed Compression Supersonic Inlets

    NASA Technical Reports Server (NTRS)

    Kopasakis, George; Connolly, Joseph W.; Paxson, Daniel E.; Woolwine, Kyle J.

    2012-01-01

    The AeroServoElasticity task under the NASA Supersonics Project is developing dynamic models of the propulsion system and the vehicle in order to conduct research for integrated vehicle dynamic performance. As part of this effort, a nonlinear quasi 1-dimensional model of the 2-dimensional bifurcated mixed compression supersonic inlet is being developed. The model utilizes computational fluid dynamics for both the supersonic and subsonic diffusers. The oblique shocks are modeled utilizing compressible flow equations. This model also implements variable geometry required to control the normal shock position. The model is flexible and can also be utilized to simulate other mixed compression supersonic inlet designs. The model was validated both in time and in the frequency domain against the legacy LArge Perturbation INlet code, which has been previously verified using test data. This legacy code written in FORTRAN is quite extensive and complex in terms of the amount of software and number of subroutines. Further, the legacy code is not suitable for closed loop feedback controls design, and the simulation environment is not amenable to systems integration. Therefore, a solution is to develop an innovative, more simplified, mixed compression inlet model with the same steady state and dynamic performance as the legacy code that also can be used for controls design. The new nonlinear dynamic model is implemented in MATLAB Simulink. This environment allows easier development of linear models for controls design for shock positioning. The new model is also well suited for integration with a propulsion system model to study inlet/propulsion system performance, and integration with an aero-servo-elastic system model to study integrated vehicle ride quality, vehicle stability, and efficiency.

  15. Reducing the number of parameters in 1D arterial blood flow modeling: less is more for patient-specific simulations.

    PubMed

    Epstein, Sally; Willemet, Marie; Chowienczyk, Phil J; Alastruey, Jordi

    2015-07-01

    Patient-specific one-dimensional (1D) blood flow modeling requires estimating model parameters from available clinical data, ideally acquired noninvasively. The larger the number of arterial segments in a distributed 1D model, the greater the number of input parameters that need to be estimated. We investigated the effect of a reduction in the number of arterial segments in a given distributed 1D model on the shape of the simulated pressure and flow waveforms. This is achieved by systematically lumping peripheral 1D model branches into windkessel models that preserve the net resistance and total compliance of the original model. We applied our methodology to a model of the 55 larger systemic arteries in the human and to an extended 67-artery model that contains the digital arteries that perfuse the fingers. Results show good agreement in the shape of the aortic and digital waveforms between the original 55-artery (67-artery) and reduced 21-artery (37-artery) models. Reducing the number of segments also enables us to investigate the effect of arterial network topology (and hence reflection sites) on the shape of waveforms. Results show that wave reflections in the thoracic aorta and renal arteries play an important role in shaping the aortic pressure and flow waves and in generating the second peak of the digital pressure and flow waves. Our novel methodology is important to simplify the computational domain while maintaining the precision of the numerical predictions and to assess the effect of wave reflections.

  16. Low-Frequency Electronic Noise in Quasi-1D TaSe3 van der Waals Nanowires.

    PubMed

    Liu, Guanxiong; Rumyantsev, Sergey; Bloodgood, Matthew A; Salguero, Tina T; Shur, Michael; Balandin, Alexander A

    2017-01-11

    We report results of investigation of the low-frequency electronic excess noise in quasi-1D nanowires of TaSe3 capped with quasi-2D h-BN layers. Semimetallic TaSe3 is a quasi-1D van der Waals material with exceptionally high breakdown current density. It was found that TaSe3 nanowires have lower levels of the normalized noise spectral density, SI/I(2), compared to carbon nanotubes and graphene (I is the current). The temperature-dependent measurements revealed that the low-frequency electronic 1/f noise becomes the 1/f(2) type as temperature increases to ∼400 K, suggesting the onset of electromigration (f is the frequency). Using the Dutta-Horn random fluctuation model of the electronic noise in metals, we determined that the noise activation energy for quasi-1D TaSe3 nanowires is approximately EP ≈ 1.0 eV. In the framework of the empirical noise model for metallic interconnects, the extracted activation energy, related to electromigration is EA = 0.88 eV, consistent with that for Cu and Al interconnects. Our results shed light on the physical mechanism of low-frequency 1/f noise in quasi-1D van der Waals semimetals and suggest that such material systems have potential for ultimately downscaled local interconnect applications.

  17. Enhancement of long-range correlations in a 2D vortex lattice by an incommensurate 1D disorder potential

    NASA Astrophysics Data System (ADS)

    Guillamon, I.; Vieira, S.; Suderow, H.; Cordoba, R.; Sese, J.; de Teresa, J. M.; Ibarra, R.

    In two dimensional (2D) systems, theory has proposed that random disorder destroys long range correlations driving a transition to a glassy state. Here, I will discuss new insights into this issue obtained through the direct visualization of the critical behaviour of a 2D superconducting vortex lattice formed in a thin film with a smooth 1D thickness modulation. Using scanning tunneling microscopy at 0.1K, we have tracked the modification in the 2D vortex arrangements induced by the 1D thickness modulation while increasing the vortex density by three orders of magnitude. Upon increasing the field, we observed a two-step order-disorder transition in the 2D vortex lattice mediated by the appearance of dislocations and disclinations and accompanied by an increase in the local vortex density fluctuations. Through a detailed analysis of correlation functions, we find that the transition is driven by the incommensurate 1D thickness modulation. We calculate the critical points and exponents and find that they are well above theoretical expectation for random disorder. Our results show that long range 1D correlations in random potentials enhance the stability range of the ordered phase in a 2D vortex lattice. Work supported by Spanish MINECO, CIG Marie Curie Grant, Axa Research Fund and FBBVA.

  18. Reducing the number of parameters in 1D arterial blood flow modeling: less is more for patient-specific simulations

    PubMed Central

    Epstein, Sally; Willemet, Marie; Chowienczyk, Phil J.

    2015-01-01

    Patient-specific one-dimensional (1D) blood flow modeling requires estimating model parameters from available clinical data, ideally acquired noninvasively. The larger the number of arterial segments in a distributed 1D model, the greater the number of input parameters that need to be estimated. We investigated the effect of a reduction in the number of arterial segments in a given distributed 1D model on the shape of the simulated pressure and flow waveforms. This is achieved by systematically lumping peripheral 1D model branches into windkessel models that preserve the net resistance and total compliance of the original model. We applied our methodology to a model of the 55 larger systemic arteries in the human and to an extended 67-artery model that contains the digital arteries that perfuse the fingers. Results show good agreement in the shape of the aortic and digital waveforms between the original 55-artery (67-artery) and reduced 21-artery (37-artery) models. Reducing the number of segments also enables us to investigate the effect of arterial network topology (and hence reflection sites) on the shape of waveforms. Results show that wave reflections in the thoracic aorta and renal arteries play an important role in shaping the aortic pressure and flow waves and in generating the second peak of the digital pressure and flow waves. Our novel methodology is important to simplify the computational domain while maintaining the precision of the numerical predictions and to assess the effect of wave reflections. PMID:25888513

  19. Reactions of HO2 with carbon monoxide and nitric oxide and of O/1 D/ with water.

    NASA Technical Reports Server (NTRS)

    Simonaitis, R.; Heicklen, J.

    1973-01-01

    Investigation of the reactions of the hydroperoxyl radical with carbon monoxide and nitric oxide in a static system, and reexamination of the reaction of O(1 D) with water. The HO2 radicals were generated by the photolysis of N2O at 2139 A in the presence of excess H2O or H2 and smaller amounts of CO and O2. The O(1 D) atoms produced from the photolysis of N2O react with H2O or with H2 to give OH radicals in the case of H2O or OH radicals and H atoms in the case of H2. With H2O, two OH radicals are produced for each O(1 D) removed at low pressures, but the OH yield drops as the pressure is raised. This drop is attributed to an insertion reaction which removes from 10 to 30% of the O(1 D) atoms at about 650 torr of H2O at 200 F. The OH radicals generated can react with either CO or H2 to produce H atoms, which then add to O2 to produce HO2. In the absence of NO, the HO2 radicals could react by two routes, while with NO present NO2 is produced in a long chain process.

  20. Full Waveform 3D Synthetic Seismic Algorithm for 1D Layered Anelastic Models

    NASA Astrophysics Data System (ADS)

    Schwaiger, H. F.; Aldridge, D. F.; Haney, M. M.

    2007-12-01

    Numerical calculation of synthetic seismograms for 1D layered earth models remains a significant aspect of amplitude-offset investigations, surface wave studies, microseismic event location approaches, and reflection interpretation or inversion processes. Compared to 3D finite-difference algorithms, memory demand and execution time are greatly reduced, enabling rapid generation of seismic data within workstation or laptop computational environments. We have developed a frequency-wavenumber forward modeling algorithm adapted to realistic 1D geologic media, for the purpose of calculating seismograms accurately and efficiently. The earth model consists of N layers bounded by two halfspaces. Each layer/halfspace is a homogeneous and isotropic anelastic (attenuative and dispersive) solid, characterized by a rectangular relaxation spectrum of absorption mechanisms. Compressional and shear phase speeds and quality factors are specified at a particular reference frequency. Solution methodology involves 3D Fourier transforming the three coupled, second- order, integro-differential equations for particle displacements to the frequency-horizontal wavenumber domain. An analytic solution of the resulting ordinary differential system is obtained. Imposition of welded interface conditions (continuity of displacement and stress) at all interfaces, as well as radiation conditions in the two halfspaces, yields a system of 6(N+1) linear algebraic equations for the coefficients in the ODE solution. An optimized inverse 2D Fourier transform to the space domain gives the seismic wavefield on a horizontal plane. Finally, three-component seismograms are obtained by accumulating frequency spectra at designated receiver positions on this plane, followed by a 1D inverse FFT from angular frequency ω to time. Stress-free conditions may be applied at the top or bottom interfaces, and seismic waves are initiated by force or moment density sources. Examples reveal that including attenuation

  1. Tandem repeats modify the structure of the canine CD1D gene.

    PubMed

    Looringh van Beeck, F A; Leegwater, P A J; Herrmann, T; Broere, F; Rutten, V P M G; Willemse, T; Van Rhijn, I

    2013-06-01

    Among the CD1 proteins that present lipid antigens to T cells, CD1d is the only one that stimulates a population of T cells with an invariant T-cell receptor known as NKT cells. Sequencing of a 722 nucleotide gap in the dog (Canis lupus familiaris) genome revealed that the canine CD1D gene lacks a sequence homologous to exon 2 of human CD1D, coding for the start codon and signal peptide. Also, the canine CD1D gene contains three different short tandem repeats that disrupt the expected gene structure. Because canine CD1D cDNA lacks sequences homologous to human exon 2 and 3, the functionality of canine CD1d protein may be affected, and this could have consequences for the development and activation of canine NKT cells.

  2. 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.

  3. GE SBWR stability analysis using TRAC-BF1 1-D kinetics model

    SciTech Connect

    Lu, S.; Baratta, A.J.; Robinson, G.E.

    1996-07-01

    GE`s simplified boiling water reactor, with its unique feature of using natural circulation to remove the heat from the reactor core, is a complicated dynamic system. Previous work by authors using the TRAC-BF1 code and a point kinetics model predicted that an SBWR may experience large amplitude power oscillation under certain low pressure and high power operating conditions. To further confirm the existence of this power oscillation and explore the dynamic spatial reactor power distribution, the TRAC-BF1 1-D kinetics model was used. The results show that an instability exists and the power oscillation starting time and maximum peak power are different from the point kinetics results.

  4. TAU: A 1D radiative transfer code for transmission spectroscopy of extrasolar planet atmospheres

    NASA Astrophysics Data System (ADS)

    Hollis, M. D. J.; Tessenyi, M.; Tinetti, G.

    2013-10-01

    The TAU code is a 1D line-by-line radiative transfer code, which is generally applicable for modelling transmission spectra of close-in extrasolar planets. The inputs are the assumed pressure-temperature profile of the planetary atmosphere, the continuum absorption coefficients and the absorption cross-sections for the trace molecular absorbers present in the model, as well as the fundamental system parameters taken from the published literature. The program then calculates the optical path through the planetary atmosphere of the radiation from the host star, and quantifies the absorption due to the modelled composition in a transmission spectrum of transit depth as a function of wavelength. The code is written in C++, parallelised using OpenMP, and is available for public download and use from http://www.ucl.ac.uk/exoplanets/. Running time: From 0:5 to 500 s, depending on run parameters

  5. TAU: A 1D radiative transfer code for transmission spectroscopy of extrasolar planet atmospheres

    NASA Astrophysics Data System (ADS)

    Hollis, M. D. J.; Tessenyi, M.; Tinetti, G.

    2014-02-01

    The TAU code is a 1D line-by-line radiative transfer code, which is generally applicable for modeling transmission spectra of close-in extrasolar planets. The inputs are the assumed temperature-pressure profile of the planetary atmosphere, the continuum absorption coefficients and the absorption cross-sections for the trace molecular absorbers present in the model, as well as the fundamental system parameters taken from the published literature. The program then calculates the optical path through the planetary atmosphere of the radiation from the host star, and quantifies the absorption due to the modeled composition in a transmission spectrum of transit depth as a function of wavelength. The code is written in C++, parallelized using OpenMP, and is available for public download and use from http://www.ucl.ac.uk/exoplanets/.

  6. Stratospheric Impact of 1D-Variation Assimilation of TOVS/ATOVS Data

    NASA Technical Reports Server (NTRS)

    Rokke, Laurie; Joiner, Joanna

    1999-01-01

    This paper will present an assessment of the impact to the stratospheric circulation of the DAO-GEOS2 (Data Assimilation Office -Goddard Earth Observing System) attributable to an improved 1D-Variational retrieval of heights. The assimilated heights are retrieved from both the TOVS (TIROS Operational Vertical Sounder) and the ATOVS (Advanced TOVS) sounders. Each sounder's sensitivity to temperature changes in the stratosphere will be addressed and its relationship to the model's background flow evaluated. Also detailed are the steps to ensure the quality of the data being assimilated. Finally the temporal and spatial scales, important to the stratospheric mean flow, will be evaluated in terms of the DAO-GEOS2 response to the assimilated heights.

  7. 1D valence bond solids in a magnetic field

    NASA Astrophysics Data System (ADS)

    Iaizzi, Adam; Sandvik, Anders W.

    2015-09-01

    A Valence bond solid (VBS) is a nonmagnetic, long-range ordered state of a quantum spin system where local spin singlets are formed in some regular pattern. We here study the competition between VBS order and a fully polarized ferromagnetic state as function of an external magnetic field in a one-dimensional extended Heisenberg model—the J-Q2 model— using stochastic series expansion (SSE) quantum Monte Carlo simulations with directed loop updates. We discuss the ground state phase diagram.

  8. 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.

  9. Multiscale Modeling Techniques for Plasmas: 1D Scaling Results and Application to Magnetic Reconnection

    NASA Astrophysics Data System (ADS)

    Shay, M. A.; Dorland, B.; Drake, J. F.; Stantchev, G.

    2005-12-01

    We examine a novel simulation scheme called "equation free projective integration"[1] which has the potential to allow global simulations which still include microscale physics, a necessary ingredient in order to model multiscale problems. Such codes could be used to examine the global effects of reconnection and turbulence in the Earth's magnetosphere, and the solar corona, as well as in laboratory Tokamaks. Using this method to simulate the propagation and steepening of a 1D ion acoustic wave, we have already achieved excellent agreement between full particle codes and equation free with a factor of 20 speed-up. This speedup appears to scale linearly with system size, so large scale 2D and 3D simulations using this method will show a speedup of 100 or more. In this method of simulation, the global plasma variables stepped forward in time are not time-integrated directly using dynamical differential equations, hence the name "equation free." Instead, these variables are represented on a microgrid using a kinetic simulation. This microsimulation is integrated forward long enough to determine the time derivatives of the global plasma variables, which are then used to integrate forward the global variables with much larger timesteps. Results will be presented of the successful application of equation free to 1-D ion acoustic wave steepening with a PIC code serving as the underlying kinetic model. Initial results of this technique applied to magnetic reconnection will also be discussed. 1 I. G. Kevrekidis et. al., Equation-free multiscale computation: Enabling microscopic simulators to perform system-level tasks, arXiv:physics/0209043.

  10. PmTBC1D20, a Rab GTPase-activating protein from the black tiger shrimp, Penaeus monodon, is involved in white spot syndrome virus infection.

    PubMed

    Yingvilasprasert, Wanchart; Supungul, Premruethai; Tassanakajon, Anchalee

    2014-02-01

    TBC (TRE2/BUB2/CDC16) domain proteins contain an ≈ 200-amino-acid motif and function as Rab GTPase-activating proteins that are required for regulating the activity of Rab proteins, and so, in turn, endocytic membrane trafficking in cells. TBC domain family member 20 (TBC1D20) has recently been reported to mediate Hepatitis C virus replication. Herein, PmTBC1D20 identified from the black tiger shrimp, Penaeus monodon, was characterized and evaluated for its role in white spot syndrome virus (WSSV) infection. The full-length cDNA sequence of PmTBC1D20 contains 2003 bp with a predicted 1443 bp open reading frame encoding a deduced 480 amino acid protein. Its transcript levels were significantly up-regulated at 24 and 48 h by ≈ 2.3- and 2.1-fold, respectively, after systemic infection with WSSV. In addition, depletion of PmTBC1D20 transcript in shrimps by double stranded RNA interference led to a decrease in the level of transcripts of three WSSV genes (VP28, ie1 and wsv477). This suggests the importance of PmTBC1D20 in WSSV infection. This is the first report of TBC1D20 in a crustacean and reveals the possible mechanism used by WSSV to modulate the activity of the host protein, PmTBC1D20, for its benefit in viral trafficking and replication.

  11. Onset of thermalization in a 1D Bose gas

    NASA Astrophysics Data System (ADS)

    Riou, Jean-Felix; Reinhard, Aaron W.; Adams, Laura; Weiss, David S.

    2011-05-01

    There has been considerable theoretical debate about how nearly integrable many-body quantum systems approach thermal equilibrium. Experiments on one dimensional Bose gases in optical lattices may shed light on this issue. We have studied the time evolution of momentum distributions of Rb clouds initially prepared in ``quantum Newton's cradle'' states [T. Kinoshita, T. Wenger and David S. Weiss, ``A quantum Newton's Cradle,'' Nature 440, 900 (2006)]. The measured evolution rates are found to depend on density and lattice depth. In order to isolate the part of the approach to equilibrium due to atom-atom interactions, it has been necessary to quantify, experimentally and theoretically, the contributions of various heating and loss processes to these rates.

  12. 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.

  13. Double resonant processes in 1D nonlinear periodic media

    NASA Astrophysics Data System (ADS)

    Kuzmiak, Vladimir; Konotop, Vladimir

    2001-03-01

    We consider one-dimensional periodic structure consisting of alternating layers fabricated from the materials possessing \\chi^(2) nonlinearity and assume that the filling fraction and the dielectric permittivities of the slabs are chosen in such a way that resonant contions for the generation for the second and third harmonic are satisfied simultaneously. The possibility of such process is demonstrated in the structure consisting of the alternating slabs of AlGaAs and InSb. The wave evolution is described in terms of envelope function approach. By taking account three resonant waves one obtains a system of coupled-mode differential equations. One of the solutions which is of special importance is that of having a constant amplitude and the first and third harmonic having zero amplitude. We analyze the stability of the solutions and show that the use of the double resonance allows one to obtain difference generation. A particular example of such a process is fractional conversion ω arrow (2/3)ω which takes place with the participation of the mode with the frequency ω/3.

  14. The Magical Geometry of 1D Quantum Liquids

    NASA Astrophysics Data System (ADS)

    Plamadeala, Eugeniu

    We investigate the edge properties of Abelian topological phases in two spatial dimensions. We discover that many of them support multiple fully chiral edge phases, with surprising and measurable experimental consequences. Using the machinery of conformal field theory and integral quadratic forms we establish that distinct chiral edge phases correspond to genera of positive-definite integral lattices. This completes the notion of bulk-boundary correspondence for topological phases. We establish that by tuning inter-channel interactions the system can be made to transition between the different edge phases without closing the bulk gap. Separately we construct a family of one-dimensional models, called Perfect Metals, with no relevant mass-generating operators. These theories describe stable quantum critical phases of interacting fermions, bosons or spins in a quantum nanowire. These models rigorously answer a long-standing question about the existence of stable metallic phases in one and two spatial dimensions in the presence of generic disorder. Separately, they are the first example of a stable phase of an infinite parallel array of coupled Luttinger liquids. We perform a detailed study of the transport properties of Perfect Metals and show that in addition to violating the Wiedemann-Franz law, they naturally exhibit low power-law dependence of electric and thermal conductivities on temperature all the way to zero temperature. We dub this phenomenological set of properties a hyperconductor because in some sense, hyperconductors are better conductors that superconductors, which may have thermal conductivities that are exponentially small in temperature.

  15. Nanoelectronic Modeling (NEMO): Moving from commercial grade 1-D simulation to prototype 3-D simulation

    NASA Astrophysics Data System (ADS)

    Klimeck, Gerhard

    2001-03-01

    The quantum mechanical functionality of commercially pursued heterostructure devices such as resonant tunneling diodes (RTDs), quantum well infrared photodetectors, and quantum well lasers are enabled by material variations on an atomic scale. The creation of these heterostructure devices is realized in a vast design space of material compositions, layer thicknesses and doping profiles. The full experimental exploration of this design space is unfeasible and a reliable design tool is needed. The Nanoelectronic Modeling tool (NEMO) is one of the first commercial grade attempts for such a modeling tool. NEMO was developed as a general-purpose quantum mechanics-based 1-D device design and analysis tool from 1993-97 by the Central Research Laboratory of Texas Instruments (later Raytheon Systems). NEMO enables(R. Lake, G. Klimeck, R. C. Bowen, and D. Jovanovic, J. Appl. Phys. 81), 7845 (1997). the fundamentally sound inclusion of the required(G. Klimeck et al.), in the 1997 55th Annual Device Research Conference Digest, (IEEE, NJ, 1997), p. 92^,(R. C. Bowen et al.), J. Appl. Phys 81, 3207 (1997). physics: bandstructure, scattering, and charge self-consistency based on the non-equilibrium Green function approach. A new class of devices which require full 3-D quantum mechanics based models is starting to emerge: quantum dots, or in general semiconductor based deca-nano devices. We are currently building a 3-D modeling tool based on NEMO to include the important physics to understand electronic stated in such superscaled structures. This presentation will overview various facets of the NEMO 1-D tool such electron transport physics in RTDs, numerical technology, software engineering and graphical user interface. The lessons learned from that work are now entering the NEMO 3-D development and first results using the NEMO 3-D prototype will be shown. More information about

  16. Density of states and extent of wave function: two crucial factors for small polaron hopping conductivity in 1D

    NASA Astrophysics Data System (ADS)

    Dimakogianni, M.; Simserides, C.; Triberis, G. P.

    2013-07-01

    We introduce a theoretical model to scrutinize the conductivity of small polarons in 1D disordered systems, focusing on two crucial - as will be demonstrated - factors: the density of states and the spatial extent of the electronic wave function. The investigation is performed for any temperature up to 300 K and under electric field of arbitrary strength up to the polaron dissociation limit. To accomplish this task, we combine analytical work with numerical calculations.

  17. Therapeutic implications of CD1d expression and tumor-infiltrating macrophages in pediatric medulloblastomas.

    PubMed

    Teo, Wan-Yee; Elghetany, M Tarek; Shen, Jianhe; Man, Tsz-Kwong; Li, Xiaonan; Chintagumpala, Murali; Su, Jack Meng Fen; Dauser, Robert; Whitehead, William; Adesina, Adekunle M; Lau, Ching C

    2014-11-01

    Immunobiology of medulloblastoma (MB), the most common malignant brain tumor in children, is poorly understood. Although tumor cells in some MBs were recently shown to express CD1d and be susceptible to Vα24-invariant natural killer T (NKT)-cell cytotoxicity, the clinical relevance of CD1d expression in MB patients remains unknown. We investigated the expression of CD1d in pediatric MBs and correlated with molecular and clinical characteristics. Specifically, we explored if NKT cell therapy can be targeted at a subset of pediatric MBs with poorer prognosis. Particularly, infantile MBs have a worse outcome because radiotherapy is delayed to avoid neurocognitive sequelae. Immunohistochemistry for CD1d was performed on a screening set of 38 primary pediatric MBs. Gene expression of the membrane form of M2 macrophage marker, CD163, was studied in an expanded cohort of 60 tumors. Outcome data was collected prospectively. Thirteen of 38 MBs (34.2 %) expressed CD1d on immunohistochemistry. CD1d was expressed mainly on MB tumor cells, and on some tumor-associated macrophages. Majority (18/22, 82 %) of non sonic-hedgehog/Wingless-activated MBs (group 3 and 4) were CD1d-negative (p = 0.05). A subset of infantile MBs (4/9, 44.4 %) expressed CD1d. Macrophages infiltrating MB expressed CD163 apart from CD1d. Molecular subtypes demonstrated statistical differences in CD163 expression, SHH-tumors were the most enriched (p = 0.006). Molecular and clinical subtypes of pediatric MB exhibit distinct differences in CD1d expression, which have important therapeutic implications. High CD1d expression in infantile MBs offers potential new immunotherapeutic treatment with NKT cell therapy in infants, where treatment is suboptimal due delayed radiotherapy.

  18. 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

  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. Analysis of Rotational Structure in the High-Resolution Infrared Spectra of the TRANS-HEXATRIENE-1,1-D2 and -CIS-1-D1 Species

    NASA Astrophysics Data System (ADS)

    Craig, Norman C.; Fuson, Hannah A.; Tian, Hengfeng; Blake, Thomas A.

    2011-06-01

    Hexatriene-1,1-D2 with some admixture of the cis-1-D1 and trans-1-D1 species was synthesized by reaction of 2,4-pentadienal and (methyl-D3)-triphenylphosphonium iodide (Wittig reagent). The trans isomer was isolated by preparative gas chromatography, and the high-resolution (0.0015 Cm-1) infrared spectrum was recorded on a Bruker IFS 125HR instrument. The rotational structure in two C-type bands for the 1,1-D2 species was analyzed. For this species the bands at 902.043 and 721.864 Cm-1 yielded composite ground state rotational constants of A0 = 0.801882(1), B0 = 0.041850(2), and C0 = 0.039804(1) Cm-1. For the cis-1-D1 species the C-type band at 803.018 Cm-1 gave A0 = 0.809384(2), B0 = 0.043530(3), and C0 = 0.041321(2) Cm-1. By iodine-catalyzed isomerization, we have obtained some of the much less favored cis isomer and hope to obtain microwave spectra for its three deuterium-substituted species. The rotational constants reported here contribute to data needed for determining a semi-experimental structure for trans-hexatriene, which should show that the structural consequences of pi-electron delocalization increase with the chain length of polyenes.

  1. 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.

  2. 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.

  3. X(3872) as a {sup 1}D{sub 2} charmonium state

    SciTech Connect

    Kalashnikova, Yu. S.; Nefediev, A. V.

    2010-11-01

    The {sup 1}D{sub 2} charmonium assignment for the X(3872) meson is considered, as prompted by a recent result from the BABAR Collaboration, favoring 2{sup -+} quantum numbers for X. It is shown that established properties of X(3872) are in a drastic conflict with the {sup 1}D{sub 2} cc assignment.

  4. A rational route to SCM materials based on a 1-D cobalt selenocyanato coordination polymer.

    PubMed

    Boeckmann, Jan; Näther, Christian

    2011-07-07

    Thermal annealing of a discrete complex with terminal SeCN anions and monodentate coligands enforces the formation of a 1D cobalt selenocyanato coordination polymer that shows slow relaxation of the magnetization. Therefore, this approach offers a rational route to 1D materials that might show single chain magnetic behaviour.

  5. The organic anion transport polypeptide 1d1 (Oatp1d1) mediates hepatocellular uptake of phalloidin and microcystin into skate liver

    SciTech Connect

    Meier-Abt, F.; Hammann-Haenni, A.; Stieger, B.; Ballatori, N.; Boyer, J.L. . E-mail: james.boyer@yale.edu

    2007-02-01

    Organic anion transporting polypeptides (rodent Oatp; human OATP) mediate cellular uptake of numerous organic compounds including xenobiotic toxins into mammalian hepatocytes. In the little skate Leucoraja erinacea a liver-specific Oatp (Oatp1d1, also called sOatp) has been identified and suggested to represent an evolutionarily ancient precursor of the mammalian liver OATP1B1 (human), Oatp1b2 (rat), and OATP1B3 (human). The present study tested whether Oatp1d1 shares functional transport activity of the xenobiotic oligopeptide toxins phalloidin and microcystin with the mammalian liver Oatps/OATPs. The phalloidin analogue [{sup 3}H]-demethylphalloin was taken up into skate hepatocytes with high affinity (Km {approx} 0.4 {mu}M), and uptake could be inhibited by phalloidin and a variety of typical Oatp/OATP substrates such as bromosulfophthalein, bile salts, estrone-3-sulfate, cyclosporine A and high concentrations of microcystin-LR (Ki {approx} 150 {mu}M). When expressed in Xenopus laevis oocytes Oatp1d1 increased uptake of demethylphalloin (Km {approx} 2.2 {mu}M) and microcystin-LR (Km {approx} 27 {mu}M) 2- to 3-fold over water-injected oocytes, whereas the alternative skate liver organic anion transporter, the dimeric Ost{alpha}/{beta}, exhibited no phalloidin and only minor microcystin-LR transport. Also, the closest mammalian Oatp1d1 orthologue, the human brain and testis OATP1C1, did not show any phalloidin transport activity. These results demonstrate that the evolutionarily ancient Oatp1d1 is able to mediate uptake of cyclic oligopeptide toxins into skate liver. The findings support the notion that Oatp1d1 is a precursor of the liver-specific mammalian Oatps/OATPs and that its transport properties are closely associated with certain forms of toxic liver injury such as for example protein phosphatase inhibition by the water-borne toxin microcystin.

  6. Non-thermal distribution of O(1D) atoms in the night-time thermosphere

    NASA Technical Reports Server (NTRS)

    Yee, Jeng-Hwa

    1988-01-01

    The 6300 A O(1D-3P) emission has been used for many years to remotely monitor the thermospheric temperature from the Doppler width of its line profile. The O(1D) atoms in the nighttime thermosphere are initially produced by the dissociative recombination of O2(+) ions with kinetic energy much greater than the thermal energy of the ambient neutrals. The validity of the technique to monitor neutral ambient temperature by measuring O(1D) 6300 A emission depends on the degree of thermalization of the O(1D) atoms. The object of this study is to calculate the velocity distribution of the O(1D) atoms and to examine the effect of nonthermal distribution on the nighttime thermospheric neutral temperature determined.

  7. Boundary Control of Linear Uncertain 1-D Parabolic PDE Using Approximate Dynamic Programming.

    PubMed

    Talaei, Behzad; Jagannathan, Sarangapani; Singler, John

    2017-03-02

    This paper develops a near optimal boundary control method for distributed parameter systems governed by uncertain linear 1-D parabolic partial differential equations (PDE) by using approximate dynamic programming. A quadratic surface integral is proposed to express the optimal cost functional for the infinite-dimensional state space. Accordingly, the Hamilton-Jacobi-Bellman (HJB) equation is formulated in the infinite-dimensional domain without using any model reduction. Subsequently, a neural network identifier is developed to estimate the unknown spatially varying coefficient in PDE dynamics. Novel tuning law is proposed to guarantee the boundedness of identifier approximation error in the PDE domain. A radial basis network (RBN) is subsequently proposed to generate an approximate solution for the optimal surface kernel function online. The tuning law for near optimal RBN weights is created, such that the HJB equation error is minimized while the dynamics are identified and closed-loop system remains stable. Ultimate boundedness (UB) of the closed-loop system is verified by using the Lyapunov theory. The performance of the proposed controller is successfully confirmed by simulation on an unstable diffusion-reaction process.

  8. Tctex1d2 Is a Negative Regulator of GLUT4 Translocation and Glucose Uptake.

    PubMed

    Shimoda, Yoko; Okada, Shuichi; Yamada, Eijiro; Pessin, Jeffrey E; Yamada, Masanobu

    2015-10-01

    Tctex1d2 (Tctex1 domain containing 2) is an open reading frame that encodes for a functionally unknown protein that contains a Tctex1 domain found in dynein light chain family members. Examination of gene expression during adipogenesis demonstrated a marked increase in Tctex1d2 protein expression that was essentially undetectable in preadipocytes and markedly induced during 3T3-L1 adipocyte differentiation. Tctex1d2 overexpression significantly inhibited insulin-stimulated glucose transporter 4 (GLUT4) translocation and 2-deoxyglucose uptake. In contrast, Tctex1d2 knockdown significantly increased insulin-stimulated GLUT4 translocation and 2-deoxyglucose uptake. However, acute insulin stimulation (up to 30 min) in 3T3-L1 adipocytes with overexpression or knockdown of Tctex1d2 had no effect on Akt phosphorylation, a critical signal transduction target required for GLUT4 translocation. Although overexpression of Tctex1d2 had no significant effect on GLUT4 internalization, Tctex1d2 was found to associate with syntaxin 4 in an insulin-dependent manner and inhibit Doc2b binding to syntaxin 4. In addition, glucose-dependent insulinotropic polypeptide rescued the Tctex1d2 inhibition of insulin-stimulated GLUT4 translocation by suppressing the Tctex1d2-syntaxin 4 interaction and increasing Doc2b-Synatxin4 interactions. Taking these results together, we hypothesized that Tctex1d2 is a novel syntaxin 4 binding protein that functions as a negative regulator of GLUT4 plasma membrane translocation through inhibition of the Doc2b-syntaxin 4 interaction.

  9. Reactions in the system HfO/sub 2/-SrO, HfO/sub 2/-BaO, and ZrO/sub 2/-BaO in high HfO/sub 2/ or ZrO/sub 2/ regions

    SciTech Connect

    Shevchenko, A.V.; Lopato, L.M.; Gerasimyuk, G.I.; Zaitseva, Z.A.

    1988-02-01

    The objective of this work was to study phase equilibria in the systems HfO/sub 2/-SrO, HfO/sub 2/-BaO, and ZrO/sub 2/-BaO in the 0 to 50 mole% SrO or BaO range and between 1600 and 2800/sup 0/C with the aid of high-temperature calcining and quenching methods. The samples' phase composition was determined by x-ray, microstructural, and petrographic methods. Samples calcined and melted in the solar furnace were analyzed by x-ray diffraction at room temperature on a DRON-1.5 diffractometer with Cu-K/sub ..cap alpha../ radiation and a Ni filter. Refractive indices were measured in high-refraction immersion liquids and in sulfur and selenium alloys. They form characteristic narrow solid solution regions based on the monoclinic, tetragonal, and cubic modifications of HfO/sub 2/(ZrO/sub 2/).

  10. Topological defect formation in 1D and 2D spin chains realized by network of optical parametric oscillators

    NASA Astrophysics Data System (ADS)

    Hamerly, Ryan; Inaba, Kensuke; Inagaki, Takahiro; Takesue, Hiroki; Yamamoto, Yoshihisa; Mabuchi, Hideo

    2016-09-01

    A network of optical parametric oscillators (OPOs) is used to simulate classical Ising and XY spin chains. The collective nonlinear dynamics of this network, driven by quantum noise rather than thermal fluctuations, seeks out the Ising/XY ground state as the system transitions from below to above the lasing threshold. We study the behavior of this “Ising machine” for three canonical problems: a 1D ferromagnetic spin chain, a 2D square lattice and problems where next-nearest-neighbor couplings give rise to frustration. If the pump turn-on time is finite, topological defects form (domain walls for the Ising model, winding number and vortices for XY) and their density can be predicted from a numerical model involving a linear “growth stage” and a nonlinear “saturation stage”. These predictions are compared against recent data for a 10,000-spin 1D Ising machine.

  11. Light-directing chiral liquid crystal nanostructures: from 1D to 3D.

    PubMed

    Bisoyi, Hari Krishna; Li, Quan

    2014-10-21

    Endowing external, remote, and dynamic control to self-organized superstructures with desired functionalities is a principal driving force in the bottom-up nanofabrication of molecular devices. Light-driven chiral molecular switches or motors in liquid crystal (LC) media capable of self-organizing into optically tunable one-dimensional (1D) and three-dimensional (3D) superstructures represent such an elegant system. As a consequence, photoresponsive cholesteric LCs (CLCs), i.e., self-organized 1D helical superstructures, and LC blue phases (BPs), i.e., self-organized 3D periodic cubic lattices, are emerging as a new generation of multifunctional supramolecular 1D and 3D photonic materials in their own right because of their fundamental academic interest and technological significance. These smart stimuli-responsive materials can be facilely fabricated from achiral LC hosts by the addition of a small amount of a light-driven chiral molecular switch or motor. The photoresponsiveness of these materials is a result of both molecular interaction and geometry changes in the chiral molecular switch upon light irradiation. The doped photoresponsive CLCs undergo light-driven pitch modulation and/or helix inversion, which has many applications in color filters, polarizers, all-optical displays, optical lasers, sensors, energy-saving smart devices, and so on. Recently, we have conceptualized and rationally synthesized different light-driven chiral molecular switches that have very high helical twisting powers (HTPs) and exhibit large changes in HTP in different states, thereby enabling wide phototunability of the systems by the addition of very small amounts of the molecular switches into commercially available achiral LCs. The light-driven chiral molecular switches are based on well-recognized azobenzene, dithienylcyclopentene, and spirooxazine derivatives. We have demonstrated high-resolution and lightweight photoaddressable displays without patterned electronics on

  12. 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.

  13. 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.

  14. GaAs solar cell photoresponse modeling using PC-1D V2.1

    NASA Technical Reports Server (NTRS)

    Huber, D. A.; Olsen, L. C.; Dunham, G.; Addis, F. W.

    1991-01-01

    Photoresponse data of high efficiency GaAs solar cells were analyzed using PC-1D V2.1. The approach required to use PC-1D for photoresponse data analysis, and the physical insights gained from performing the analysis are discussed. In particular, the effect of Al(x)Ga(1-x)As heteroface quality was modeled. Photoresponse or spectral quantum efficiency is an important tool in characterizing material quality and predicting cell performance. The strength of the photoresponse measurement lies in the ability to precisely fit the experimental data with a physical model. PC-1D provides a flexible platform for calculations based on these physical models.

  15. 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

  16. 2D Biotope Mapping Using Combined LIDAR, Topographic Survey And Segmented 1D Flow Modelling

    NASA Astrophysics Data System (ADS)

    Entwistle, N. S.; Heritage, G. L.; Milan, D. J.

    2009-12-01

    Reach averaged habitat availability models such as PHABSIM are limited due principally to their failure to adequately map hydraulic habitat distribution at a representative scale. A lack of morphologic data, represented in the form of sparse geometric cross-sections fails to generate the necessary detail. Advances in data collection, improved spatial modelling algorithms and the advent of cross-section based segmentation routines in 1D hydraulic models provides the opportunity to revisit the issue of hydraulic habitat mapping and modelling. This paper presents a combined technique for habitat characterisation at the sub-bar scale is presented for the River Rede, Northumberland, UK. Terrestrial LIDAR data of floodplain, banks and exposed bar surfaces at an average 0.05 m spacing are combined with sparser total station survey data of submerged morphologic features. These data are interpolated to create a uniform DEM grid at 0.2 m spacing (adequate to detect the smallest variation in hydraulic habitat in this system). The data grid were then imported into the HECRAS 1D hydraulic model to generate a 2 m spaced series of cross-sections along a 220 m sinuous single thread reach exhibiting pool - riffle point-bar morphology. The hydraulic segmentation routine then generated estimates of depth averaged flow velocity, flow depth and sub unit discharge for 40 sub-divisions of the flow width for a series of flows from 0.5 m3s-1 up to bankfull flow of approximately 9 m3s-1. The resultant hydraulic data were exported in the project coordinate system and plotted to reveal the 2D pattern of hydraulic biotopes present across the range of flows modelled. The results reveal broadly realistic patterns consistent with previous empirical studies and compare well with LIDAR based biotope maps. Analysis of the temporal pattern of biotope change indicates that biotope diversity and complexity is at a maximum at lower flows and across shallower area (riffles) and that these dominate the

  17. Involvement of Dopamine D1/D5 and D2 Receptors in Context-Dependent Extinction Learning and Memory Reinstatement

    PubMed Central

    André, Marion Agnès Emma; Manahan-Vaughan, Denise

    2016-01-01

    Dopamine contributes to the regulation of higher order information processing and executive control. It is important for memory consolidation processes, and for the adaptation of learned responses based on experience. In line with this, under aversive learning conditions, application of dopamine receptor antagonists prior to extinction result in enhanced memory reinstatement. Here, we investigated the contribution of the dopaminergic system to extinction and memory reinstatement (renewal) of an appetitive spatial learning task in rodents. Rats were trained for 3 days in a T-maze (context “A”) to associate a goal arm with a food reward, despite low reward probability (acquisition phase). On day 4, extinction learning (unrewarded) occurred, that was reinforced by a context change (“B”). On day 5, re-exposure to the (unrewarded) “A” context took place (renewal of context “A”, followed by extinction of context “A”). In control animals, significant extinction occurred on day 4, that was followed by an initial memory reinstatement (renewal) on day 5, that was, in turn, succeeded by extinction of renewal. Intracerebral treatment with a D1/D5-receptor antagonist prior to the extinction trials, elicited a potent enhancement of extinction in context “B”. By contrast, a D1/D5-agonist impaired renewal in context “A”. Extinction in the “A” context on day 5 was unaffected by the D1/D5-ligands. Treatment with a D2-receptor antagonist prior to extinction had no overall effect on extinction in context “B” or renewal in context “A”, although extinction of the renewal effect was impaired on day 5, compared to controls. Taken together, these data suggest that dopamine acting on the D1/D5-receptor modulates both acquisition and consolidation of context-dependent extinction. By contrast, the D2-receptor may contribute to context-independent aspects of this kind of extinction learning. PMID:26834599

  18. Determination of the absolute configuration of (+)-neopentyl-1-d alcohol by neutron and x-ray diffraction analysis

    SciTech Connect

    Yuan, H.S.H.; Stevens, R.C.; Bau, R. ); Mosher, H.S. ); Koetzle, T.F. )

    1994-12-20

    The absolute configuration of (+)-neopentyl-1-d alcohol, prepared by the reduction of 2,2-dimethylpropanol-1-d by actively fermenting yeast, has been determined to be S by neutron diffraction. The neutron study was carried out on the phthalate half ester of neopentyl-1-d alcohol, crystallized as its strychnine salt. The absolute configuration of the (-)-strychninium cation was first determined by an x-ray anomalous dispersion study of its iodide salt. The chiral skeleton of strychnine then served as a reference from which the absolute configuration of the -O-CHD-C(CH[sub 3])[sub 3] group of neopentyl phthalate was determined. Difference Fourier maps calculated from the neutron data showed unambiguously that the -O-CHD-C(CH[sub 3])[sub 3] groups of both independent molecules in the unit cell had the S configuration. This work proves conclusively that the yeast system reduces aldehydes by delivering hydrogen to the re face of the carbonyl group. Crystallographic details: (-)-strychninium (+)-neopentyl-1-d phthalate, space group P2[sub 1] (monoclinic), a = 18.564(6) [angstrom], b = 7.713(2) [angstrom], c = 23.361(8) [angstrom], [beta] = 94.18(4)[degrees], V = 3336.0(5) [angstrom][sup 3], Z = 2 (T = 100 K). Final agreement factors are R(F) = 0.073 for 2768 reflections collected at room temperature (x-ray analysis) and R(F) = 0.144 for 960 reflections collected at 100 K (neutron analysis). 49 refs., 7 figs., 2 tabs.

  19. 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.

  20. Multicolour far infrared photometry of galactic H2 regions. [data acquisition using high altitude balloons

    NASA Technical Reports Server (NTRS)

    Olthof, H.

    1974-01-01

    Results are presented of far infrared photometric measurements of H2 regions in the galactic plane between longitudes 350 and 40 degrees. The results are combined from balloon flights in 1972 and 1973 carried out in cooperation with CNES in the south of France.

  1. Application of the Ribosomal DNA ITS2 Region of Physalis (Solanaceae): DNA Barcoding and Phylogenetic Study.

    PubMed

    Feng, Shangguo; Jiang, Mengying; Shi, Yujun; Jiao, Kaili; Shen, Chenjia; Lu, Jiangjie; Ying, Qicai; Wang, Huizhong

    2016-01-01

    Recently, commercial interest in Physalis species has grown worldwide due to their high nutritional value, edible fruit, and potential medicinal properties. However, many Physalis species have similar shapes and are easily confused, and consequently the phylogenetic relationships between Physalis species are poorly understood. This hinders their safe utilization and genetic resource conservation. In this study, the nuclear ribosomal ITS2 region was used to identify species and phylogenetically examine Physalis. Eighty-six ITS2 regions from 45 Physalis species were analyzed. The ITS2 sequences were aligned using Clustal W and genetic distances were calculated using MEGA V6.0. The results showed that ITS2 regions have significant intra- and inter-specific divergences, obvious barcoding gaps, and higher species discrimination rates (82.2% for both the BLASTA1 and nearest distance methods). In addition, the secondary structure of ITS2 provided another way to differentiate species. Cluster analysis based on ITS2 regions largely concurred with the relationships among Physalis species established by many previous molecular analyses, and showed that most sections of Physalis appear to be polyphyletic. Our results demonstrated that ITS2 can be used as an efficient and powerful marker in the identification and phylogenetic study of Physalis species. The technique provides a scientific basis for the conservation of Physalis plants and for utilization of resources.

  2. Application of the Ribosomal DNA ITS2 Region of Physalis (Solanaceae): DNA Barcoding and Phylogenetic Study

    PubMed Central

    Feng, Shangguo; Jiang, Mengying; Shi, Yujun; Jiao, Kaili; Shen, Chenjia; Lu, Jiangjie; Ying, Qicai; Wang, Huizhong

    2016-01-01

    Recently, commercial interest in Physalis species has grown worldwide due to their high nutritional value, edible fruit, and potential medicinal properties. However, many Physalis species have similar shapes and are easily confused, and consequently the phylogenetic relationships between Physalis species are poorly understood. This hinders their safe utilization and genetic resource conservation. In this study, the nuclear ribosomal ITS2 region was used to identify species and phylogenetically examine Physalis. Eighty-six ITS2 regions from 45 Physalis species were analyzed. The ITS2 sequences were aligned using Clustal W and genetic distances were calculated using MEGA V6.0. The results showed that ITS2 regions have significant intra- and inter-specific divergences, obvious barcoding gaps, and higher species discrimination rates (82.2% for both the BLASTA1 and nearest distance methods). In addition, the secondary structure of ITS2 provided another way to differentiate species. Cluster analysis based on ITS2 regions largely concurred with the relationships among Physalis species established by many previous molecular analyses, and showed that most sections of Physalis appear to be polyphyletic. Our results demonstrated that ITS2 can be used as an efficient and powerful marker in the identification and phylogenetic study of Physalis species. The technique provides a scientific basis for the conservation of Physalis plants and for utilization of resources. PMID:27486467

  3. 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.

  4. Vorticity and Λ polarization in event-by-event (3+1)D viscous hydrodynamics

    NASA Astrophysics Data System (ADS)

    Pang, Long-Gang; Fang, Ren-Hong; Petersen, Hannah; Wang, Qun; Wang, Xin-Nian

    2017-01-01

    We visualized the vortical fluid in fluctuating QGP using (3+1)D viscous hydrodynamics, computed the spin distribution and correlation of hyperons and estimated the polarization splitting between Λ and .

  5. Quasi-one dimensional (Q1D) nanostructures: Synthesis, integration and device application

    NASA Astrophysics Data System (ADS)

    Chien, Chung-Jen

    Quasi-one-dimensional (Q1D) nanostructures such as nanotubes and nanowires have been widely regarded as the potential building blocks for nanoscale electronic, optoelectronic and sensing devices. In this work, the content can be divided into three categories: Nano-material synthesis and characterizations, alignment and integration, physical properties and application. The dissertation consists of seven chapters as following. Chapter 1 will give an introduction to low dimensional nano-materials. Chapter 2 explains the mechanism how Q1D nanostructure grows. Chapter 3 describes the methods how we horizontally and vertically align the Q1D nanostructure. Chapter 4 and 5 are the electrical and optical device characterization respectively. Chapter 6 demonstrates the integration of Q1D nanostructures and the device application. The last chapter will discuss the future work and conclusion of the thesis.

  6. Ruthenium and osmium complexes of hemilabile chiral monophosphinite ligands derived from 1D-pinitol or 1D-chiro-inositol as catalysts for asymmetric hydrogenation reactions.

    PubMed

    Slade, Angela T; Lensink, Cornelis; Falshaw, Andrew; Clark, George R; Wright, L James

    2014-12-07

    The monophosphinite ligands, 1D-1,2;5,6-di-O-cyclopentylidene-3-O-methyl-4-O-diphenylphosphino-chiro-inositol (D-P1), 1D-1,2;5,6-di-O-isopropylidene-3-O-methyl-4-O-diphenylphosphino-chiro-inositol (D-P2), 1D-1,2;5,6-di-O-cyclohexylidene-3-O-methyl-4-O-diphenylphosphino-chiro-inositol (D-P3), and 1D-1,2;5,6-di-O-cyclopentylidene-3-O-ethyl-4-O-diphenylphosphino-chiro-inositol (D-P4), can be conveniently prepared from the chiral natural products 1D-pinitol or 1D-chiro-inositol. On treatment of toluene solutions of RuCl2(PPh3)3 with two mole equivalents of the ligands D-PY (Y = 1-4) the complexes RuCl2(D-P1)2 (1), RuCl2(D-P2)2 (4), RuCl2(D-P3)2 (5), or RuCl2(D-P4)2 (6), respectively, are formed. Similarly, treatment of OsCl2(PPh3)3 with D-P1 gives OsCl2(D-P1)2 (7). The single crystal X-ray structure determination of 1 reveals that each D-P1 ligand coordinates to ruthenium through phosphorus and the oxygen atom of the methoxyl group. Treatment of 1 with excess LiBr or LiI results in metathesis of the chloride ligands and RuBr2(D-P1)2 (2) or RuI2(D-P1)2 (3), respectively, are formed. Exposure of a solution of 1 to carbon monoxide results in the very rapid formation of RuCl2(CO)2(D-P1)2 (8), thereby demonstrating the ease with which the oxygen donors are displaced from the metal and hence the hemilabile nature of the two bidentate D-P1 ligands in 1. Preliminary studies indicate that 1-7 act as catalysts for the asymmetric hydrogenation reactions of acetophenone and 3-quinuclidinone to give the corresponding alcohols in generally high conversions but low enantiomeric excesses.

  7. Design, synthesis, and functional activity of labeled CD1d glycolipid agonists.

    PubMed

    Jervis, Peter J; Polzella, Paolo; Wojno, Justyna; Jukes, John-Paul; Ghadbane, Hemza; Garcia Diaz, Yoel R; Besra, Gurdyal S; Cerundolo, Vincenzo; Cox, Liam R

    2013-04-17

    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 attaching

  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. 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)).

  10. 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.

  11. Energy dependent 3-body loss in out-of-equilibrium 1D Bose gases

    NASA Astrophysics Data System (ADS)

    Zundel, Laura; Xia, Lin; Wilson, Joshua; Riou, Jean-Felix; Weiss, David

    2015-05-01

    We measure the three-body loss of out-of-equilibrium one-dimensional (1D) Bose gases and find that it depends strongly on the average energy of the distribution. The theory of three-body loss in 1D gas experiments is incomplete due to the challenge of calculating how correlations evolve. We present an empirical model based on energy dependent correlations and show that it reproduces the data.

  12. 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

  13. The structure of nanocomposite 1D cationic conductor crystal@SWNT.

    PubMed

    Kiselev, N A; Kumskov, A S; Zakalyukin, R M; Vasiliev, A L; Chernisheva, M V; Eliseev, A A; Krestinin, A V; Freitag, B; Hutchison, J L

    2012-06-01

    Nanocomposites consisting of one-dimensional (1D) crystals of the cationic conductors CuI, CuBr and AgBr inside single-walled carbon nanotubes, mainly (n, 0), were obtained using the capillary technique. 1D crystal structure models were proposed based on the high resolution transmission electron microscopy performed on a FEI Titan 80-300 at 80 kV with aberration correction. According to the models and image simulations there are two modifications of 1D crystal: hexagonal close-packed bromine (iodine) anion sublattice (growth direction <001>) and 1D crystal cubic structure (growth direction <112>) compressed transversely to the nanotube (D(m) ∼1.33 nm) axis. Tentatively this kind of 1D crystal can be considered as monoclinic. One modification of the anion sublattice reversibly transforms into the other inside the nanotube, probably initiated by electron beam heating. As demonstrated by micrographs, copper or silver cations can occupy octahedral positions or are statistically distributed across two tetrahedral positions. A 1DAgBr@SWNT (18, 0; 19, 0) pseudoperiodic 'lattice distortion' is revealed resulting from convolution of the nanotube wall function image with 1D cubic crystal function image.

  14. 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

  15. Generation of Multiband Chorus in the Earth's Magnetosphere: 1-D PIC Simulation

    NASA Astrophysics Data System (ADS)

    Gao, Xinliang; Ke, Yangguang; Lu, Quanming; Chen, Lunjin; Wang, Shui

    2017-01-01

    Multiband chorus waves, where the frequency of upper band chorus is about twice that of lower band chorus, have recently been reported based on THEMIS observations. The generation of multiband chorus waves is attributed to the mechanism of lower band cascade, where upper band chorus is excited via the nonlinear coupling process between lower band chorus and the associated density mode with the frequency equal to that of lower band chorus. In this letter, with a one-dimensional (1-D) particle-in-cell (PIC) simulation model, we have successfully reproduced multiband chorus waves. During the simulation, the significant density fluctuation is driven by the fluctuating electric field along the wave vector of the pump wave (lower band chorus), which can be directly observed in this self-consistent plasma system. Then, the second harmonic of the pump whistler-mode wave (upper band chorus) is generated. After quantitatively analyzing resonant conditions among wave numbers, we can confirm that the generation is caused due to the coupling between the pump wave and the density fluctuation along its wave vector. The third harmonic can also be excited through lower band cascade if the pump whistler-mode wave has a sufficiently large amplitude. Our simulation results not only provide a theoretical support to the mechanism of lower band cascade to generate multiband chorus but also propose a new pattern of evolution for whistler-mode waves in the Earth's magnetosphere.

  16. O(1S → 1D,3P) branching ratio as measured in the terrestrial nightglow

    NASA Astrophysics Data System (ADS)

    Slanger, T. G.; Cosby, P. C.; Sharpee, B. D.; Minschwaner, K. R.; Siskind, D. E.

    2006-12-01

    The branching ratio of the two optically forbidden atmospheric emission lines, O(1S - 1D) at 557.7 nm and O(1S - 3P) at 297.2 nm, is a fixed number in the upper atmosphere because the O(1S) level is common to both lines. The value for the ratio A(557.7)/A(297.2) currently recommended by NIST is 16.7, and the ratio found in the laboratory is somewhat larger. Field observations require space-based instruments, in which case calibration between the two wavelength regions is the critical issue. We circumvent this problem by using the O2(A-X) Herzberg I emission system as a bridge between the UV region below 310 nm and the ground-accessible region above that wavelength. These two spectral regions can be separately calibrated in terms of intensity, and the results of a disparate set of observations (satellite, rocket, ground-based sky spectra) lead to a quite consistent value of 9.8 ± 1.0 for A(557.7)/A(297.2). This conclusion has consequences for auroral and dayglow processes and for spectral calibration. It is particularly important to ascertain the cause of the substantial difference between this value and those from theory.

  17. The O(1S - 1D,3P) Line Intensity Ratio

    NASA Astrophysics Data System (ADS)

    Slanger, T. G.; Sharpee, B. D.; Cosby, P. C.; Minschwaner, K. R.; Siskind, D. E.

    2005-05-01

    The line intensity ratio of the two optically-forbidden atmospheric emissions, O(1S-1D) at 557.7 nm and O(1S-3P) at 297.2 nm, must be a single-valued number in the upper atmosphere because the upper level is common to both lines. The calculated transition probability ratio A(557.7)/A(297.2) is 16, by several authors, and the ratio found in the laboratory is significantly larger. Field observations require space-based instruments, in which case calibration between the two wavelengths is the critical issue. We circumvent this problem by using the O2 Herzberg I emission system as a bridge between the UV region below 310 nm and the ground-accessible region above that wavelength. These two spectral regions can be separately calibrated in terms of intensity, and the results of a disparate set of observations (satellite, rocket, ground-based) lead to A(557.7)/A(297.2) ratios that are consistently much smaller than the calculated value. These results have consequences for auroral and dayglow processes, and it is particularly important to ascertain the cause of the substantial difference between theory and observation.

  18. A Deconstruction Lattice Description of the D1/D5 Brane World-Volume Gauge Theory

    DOE PAGES

    Giedt, Joel

    2011-01-01

    I genermore » alize the deconstruction lattice formulation of Endres and Kaplan to two-dimensional super-QCD with eight supercharges, denoted by (4,4), and bifundamental matter. I specialize to a particularly interesting (4,4) gauge theory, with gauge group U ( N c ) × U ( N f ) , and U ( N f ) being weakly gauged. It describes the infrared limit of the D1/D5 brane system, which has been studied extensively as an example of the AdS 3 /CFT 2 correspondence. The construction here preserves two supercharges exactly and has a lattice structure quite similar to that which has previously appeared in the deconstruction approach, that is, site, link, and diagonal fields with both the Bose and Fermi statistics. I remark on possible applications of the lattice theory that would test the AdS 3 /CFT 2 correspondence, particularly one that would exploit the recent worldsheet instanton analysis of Chen and Tong.« less

  19. Kinetics of O(1D) + H2O and O(1D) + H2: absolute rate coefficients and O(3P) yields between 227 and 453 K.

    PubMed

    Vranckx, Stijn; Peeters, Jozef; Carl, Shaun

    2010-08-28

    The rate coefficients for the crucial atmospheric reactions of O((1)D) with H(2)O and H(2), k(1) and k(2), were measured over a wide temperature range using O((1)D) detection based on the chemiluminescence reaction of O((1)D) with C(2)H. Analyzing the decays of the chemiluminescence intensities yielded a value for k(1)(T) of (1.70 x 10(-10)exp[36 K/T]) cm(3) s(-1). Multiplying or dividing k(1)(T) by a factor f(T) = 1.04 exp(5.59(|1 K/T- 1/287|)), gives the 95% confidence limits; our new determination, in good agreement with previous studies, further reduces the uncertainty in k(1). An extended study of k(2) yielded a temperature independent rate constant of (1.35 +/- 0.05) x 10(-10) cm(3) s(-1). This precise value, based on an extended set of determinations with very low scatter, is significantly larger than the current recommendations, as were two other recent k(2) determinations. Secondly, the fractions of O((1)D) quenched to O((3)P) by H(2)O and H(2), k(1b)/k(1) and k(2b)/k(2), were precisely determined from fits to chemiluminescence decays. A temperature-independent value for k(1b)/k(1) of 0.010 +/- 0.003 was found. For the quenching fraction k(2b)/k(2) a value of 0.007 +/- 0.007 was obtained at room temperature. Both determinations are significantly smaller than values and upper limits from previous studies.

  20. Synthesis and Electron Field-Emission of 1-D Carbon-Related Nanostructured Materials

    NASA Astrophysics Data System (ADS)

    Shih, Han C.

    2002-10-01

    Carbon nanotubes, a new stable form of carbon that was first identified in 1991 [1], are fullerene-related structures which consist of graphitic cylinders closed at either end with caps containing pentagonal rings. Although carbon nanotube structures are closely related to graphite, the curvature, symmetry and small size induce marked deviations from the graphitic behavior. Various methods have been used to produce carbon nanotubes, e.g., arc-discharge, laser-vaporization, catalytic chemical vapor deposition, but too many impurities also be produced, such as fullerenes, carbon nanoparticles and amorphous carbons. The microwave plasma enhanced chemical vapor deposition (MPECVD) system has been used to grow carbon nanotubes in this work and other 1-D carbon-related nanostructured materials was synthesized by the electron cyclotron resonance (ECR) plasma system. Plasma is generated by microwave excitation at 2.45 GHz by a magnetron passes through a waveguide and fed perpendicularly through a quartz dome into an 875 G magnetic field generated by the coils surrounding the resonance volume that creates the ECR condition. The deposition chamber was pumped down to the base pressure of 6.7X10-4 Pa (5X10-6 Torr) with a turbomolecular pump for ECR-plasma and subatmospheric pressures for MPECVD by a rotary mechanical pump. Well-aligned carbon-related nanostructures have been synthesized in nanoporous alumina or silicon with a uniform diameter of 30-100 nm by microwave excited plasma of CH_4, C_2H_2, N_2, H2 and Ar precursors. Nickel nanowires not only serve as catalysts to decompose hydrocarbons to form nanostructures but also function as an electrical conductor for other advanced applications. A negative dc bias is always applied to the substrate to promote the flow of ion fluxes through the nanochannels of the template materials that facilitate the physical adsorption and subsequent chemical absorption in the formation of carbon- and carbon-nitride nanotubes[2]. The electron

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

    SciTech Connect

    Miller, David Scott

    2000-08-01

    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.

  2. The autophagy machinery restrains iNKT cell activation through CD1D1 internalization.

    PubMed

    Keller, Christian W; Loi, Monica; Ewert, Svenja; Quast, Isaak; Theiler, Romina; Gannagé, Monique; Münz, Christian; De Libero, Gennaro; Freigang, Stefan; Lünemann, Jan D

    2017-03-15

    Invariant natural killer T (iNKT) cells are innate T cells with powerful immune regulatory functions that recognize glycolipid antigens presented by the CD1D protein. While iNKT-cell-activating glycolipids are currently being explored for their efficacy to improve immunotherapy against infectious diseases and cancer, little is known about the mechanisms that control CD1D antigen presentation and iNKT cell activation in vivo. CD1D molecules survey endocytic pathways to bind lipid antigens in MHC class II containing compartments (MIICs) before recycling to the plasma membrane. Autophagosomes intersect with MIICs and autophagy-related proteins are known to support antigen loading for increased CD4(+) T cell immunity. Here, we report that mice with dendritic cell (DC)-specific deletion of the essential autophagy gene Atg5 showed better CD1D1-restricted glycolipid presentation in vivo. These effects led to enhanced iNKT cell cytokine production upon antigen recognition and lower bacterial loads during Sphingomonas paucimobilis infection. Enhanced iNKT cell activation was independent of receptor-mediated glycolipid uptake or costimulatory signals. Instead, loss of Atg5 in DCs impaired clathrin-dependent internalization of CD1D1 molecules via the adaptor protein complex 2 (AP2) and, thus, increased surface expression of stimulatory CD1D1-glycolipid complexes. These findings indicate that the autophagic machinery assists in the recruitment of AP2 to CD1D1 molecules resulting in attenuated iNKT cell activation, in contrast to the supporting role of macroautophagy in CD4(+) T cell stimulation.

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

    NASA Astrophysics Data System (ADS)

    Miller, David Scott

    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.

  4. A One-Dimensional (1-D) Three-Region Model for a Bubbling Fluidized-Bed Adsorber

    SciTech Connect

    Lee, Andrew; Miller, David C.

    2012-01-01

    A general one-dimensional (1-D), three-region model for a bubbling fluidized-bed adsorber with internal heat exchangers has been developed. The model can predict the hydrodynamics of the bed and provides axial profiles for all temperatures, concentrations, and velocities. The model is computationally fast and flexible and allows for any system of adsorption and desorption reactions to be modeled, making the model applicable to any adsorption process. The model has been implemented in both gPROMS and Aspen Custom Modeler, and the behavior of the model has been verified.

  5. 1-D/3-D geologic model of the Western Canada Sedimentary Basin

    USGS Publications Warehouse

    Higley, D.K.; Henry, M.; Roberts, L.N.R.; Steinshouer, D.W.

    2005-01-01

    The 3-D geologic model of the Western Canada Sedimentary Basin comprises 18 stacked intervals from the base of the Devonian Woodbend Group and age equivalent formations to ground surface; it includes an estimated thickness of eroded sediments based on 1-D burial history reconstructions for 33 wells across the study area. Each interval for the construction of the 3-D model was chosen on the basis of whether it is primarily composed of petroleum system elements of reservoir, hydrocarbon source, seal, overburden, or underburden strata, as well as the quality and areal distribution of well and other data. Preliminary results of the modeling support the following interpretations. Long-distance migration of hydrocarbons east of the Rocky Mountains is indicated by oil and gas accumulations in areas within which source rocks are thermally immature for oil and (or) gas. Petroleum systems in the basin are segmented by the northeast-trending Sweetgrass Arch; hydrocarbons west of the arch were from source rocks lying near or beneath the Rocky Mountains, whereas oil and gas east of the arch were sourced from the Williston Basin. Hydrocarbon generation and migration are primarily due to increased burial associated with the Laramide Orogeny. Hydrocarbon sources and migration were also influenced by the Lower Cretaceous sub-Mannville unconformity. In the Peace River Arch area of northern Alberta, Jurassic and older formations exhibit high-angle truncations against the unconformity. Potential Paleozoic though Mesozoic hydrocarbon source rocks are in contact with overlying Mannville Group reservoir facies. In contrast, in Saskatchewan and southern Alberta the contacts are parallel to sub-parallel, with the result that hydrocarbon source rocks are separated from the Mannville Group by seal-forming strata within the Jurassic. Vertical and lateral movement of hydrocarbons along the faults in the Rocky Mountains deformed belt probably also resulted in mixing of oil and gas from numerous

  6. Use of ITS2 Region as the Universal DNA Barcode for Plants and Animals

    PubMed Central

    Luo, Kun; Han, Jianping; Li, Ying; Pang, Xiaohui; Xu, Hongxi; Zhu, Yingjie; Xiao, Peigen; Chen, Shilin

    2010-01-01

    Background The internal transcribed spacer 2 (ITS2) region of nuclear ribosomal DNA is regarded as one of the candidate DNA barcodes because it possesses a number of valuable characteristics, such as the availability of conserved regions for designing universal primers, the ease of its amplification, and sufficient variability to distinguish even closely related species. However, a general analysis of its ability to discriminate species in a comprehensive sample set is lacking. Methodology/Principal Findings In the current study, 50,790 plant and 12,221 animal ITS2 sequences downloaded from GenBank were evaluated according to sequence length, GC content, intra- and inter-specific divergence, and efficiency of identification. The results show that the inter-specific divergence of congeneric species in plants and animals was greater than its corresponding intra-specific variations. The success rates for using the ITS2 region to identify dicotyledons, monocotyledons, gymnosperms, ferns, mosses, and animals were 76.1%, 74.2%, 67.1%, 88.1%, 77.4%, and 91.7% at the species level, respectively. The ITS2 region unveiled a different ability to identify closely related species within different families and genera. The secondary structure of the ITS2 region could provide useful information for species identification and could be considered as a molecular morphological characteristic. Conclusions/Significance As one of the most popular phylogenetic markers for eukaryota, we propose that the ITS2 locus should be used as a universal DNA barcode for identifying plant species and as a complementary locus for CO1 to identify animal species. We have also developed a web application to facilitate ITS2-based cross-kingdom species identification (http://its2-plantidit.dnsalias.org). PMID:20957043

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

    PubMed

    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

    2015-10-07

    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.

  8. Lars Onsager Prize Talk: 1+1d conformal field theories as natural languages for asymptotically large-scale quantum computing

    NASA Astrophysics Data System (ADS)

    Friedan, Daniel

    2010-03-01

    An abstract argument is offered that the ideal physical systems for asymptotically large-scale quantum computers are near-critical quantum circuits, critical in the bulk, whose bulk universality classes are described by 1+1d conformal field theories. One in particular -- the Monster conformal field theory -- is especially ideal, because all of its bulk couplings are irrelevant.

  9. Dynamical Analysis and Big Bang Bifurcations of 1D and 2D Gompertz's Growth Functions

    NASA Astrophysics Data System (ADS)

    Rocha, J. Leonel; Taha, Abdel-Kaddous; Fournier-Prunaret, D.

    In this paper, we study the dynamics and bifurcation properties of a three-parameter family of 1D Gompertz's growth functions, which are defined by the population size functions of the Gompertz logistic growth equation. The dynamical behavior is complex leading to a diversified bifurcation structure, leading to the big bang bifurcations of the so-called “box-within-a-box” fractal type. We provide and discuss sufficient conditions for the existence of these bifurcation cascades for 1D Gompertz's growth functions. Moreover, this work concerns the description of some bifurcation properties of a Hénon's map type embedding: a “continuous” embedding of 1D Gompertz's growth functions into a 2D diffeomorphism. More particularly, properties that characterize the big bang bifurcations are considered in relation with this coupling of two population size functions, varying the embedding parameter. The existence of communication areas of crossroad area type or swallowtails are identified for this 2D diffeomorphism.

  10. Defective transient endogenous spleen colony formation in S1/S1d mice.

    PubMed

    Wiktor-Jedrzejczak, W; Ahmed, A; Sharkis, S J; McKee, A; Sell, K W

    1979-04-01

    WCB6F1 mice of the genotype S1/S1d did not form transient 5-day endogenous spleen colonies following midlethal irradiation, either spontaneously or in response to postirradiation bleeding. Their hematologically normal (+/+) littermates produced colonies equivalent in number and morphologic type to a normal strain (D2B6F1), as evaluated by both macroscopic and microscopic criteria. Bone marrow cells from S1/S1d mice, when transplanted into lethally irradiated +/+ mice, were able to generate equivalent numbers of transient endogenous spleen colonies (TE-CFUs), as compared to that obtained when syngeneic +/+ marrow cells were injected into lethally irradiated +/+ recipients. A defective growth of an early class of hematopoietic progenitor cells, resulting in the clinical course of the S1/S1d anemia is suggested and confirms previous reports on the microenvironmental nature of this abnormality.

  11. TBC1D24 Mutation Causes Autosomal Dominant Non-Syndromic Hearing Loss

    PubMed Central

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

    2014-01-01

    Hereditary hearing loss (HHL) 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 non-syndromic hearing loss (ADNSHL) we used OtoSCOPE® to exclude mutations in known deafness genes and then performed segregation mapping and whole exome sequencing (WES) 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 (ARNSHL), syndromic hearing impairment associated with onychodystrophy, osteodystrophy, mental retardation and seizures (DOORS syndrome), and a wide range of epileptic disorders. PMID:24729539

  12. Peptide conjugates for directing the morphology and assembly of 1D nanoparticle superstructures.

    PubMed

    Zhang, Chen; Song, Chengyi; Fry, H Christopher; Rosi, Nathaniel L

    2014-01-20

    Designed peptide conjugates molecules are used to direct the synthesis and assembly of gold nanoparticles into complex 1D nanoparticle superstructures with various morphologies. Four peptide conjugates, each based on the gold-binding peptide (AYSSGAPPMPPF; PEPAu ), are prepared: C12H23O-AYSSGAPPMPP (1), C12H23O-AYSSGAPPMPPF (2), C12H23O-AYSSGAPPMPPFF (3), and C12H23O-AYSSGAPPMPPFFF (4). The affect that C-terminal hydrophobic F residues have on both the soft-assembly of the peptide conjugates and the resulting assembly of gold nanoparticle superstructures is examined. It is shown that the addition of two C-terminal F residues (3) leads to thick, branched 1D gold nanoparticle superstructures, whereas the addition of three C-terminal F residues (4) leads to bundling of thin 1D nanoparticle superstructures.

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

    NASA Astrophysics Data System (ADS)

    Malamud, Uri; Prialnik, Dina

    2016-04-01

    We develop a long-term 1-D evolution model for icy satellites that couples multiple processes: water migration and differentiation, geochemical reactions and silicate phase transitions, compaction by self-gravity, and ablation. The model further considers the following energy sources and sinks: tidal heating, radiogenic heating, geochemical energy released by serpentinization or absorbed by mineral dehydration, gravitational energy and insolation, and heat transport by conduction, convection, and advection. We apply the model to Enceladus, by guessing the initial conditions that would render a structure compatible with present-day observations, assuming the initial structure to have been homogeneous. Assuming the satellite has been losing water continually along its evolution, we postulate that it was formed as a more massive, more icy and more porous satellite, and gradually transformed into its present day state due to sustained long-term tidal heating. We consider several initial compositions and evolution scenarios and follow the evolution for the age of the Solar System, testing the present day model results against the available observational constraints. Our model shows the present configuration to be differentiated into a pure icy mantle, several tens of km thick, overlying a rocky core, composed of dehydrated rock at the center and hydrated rock in the outer part. For Enceladus, it predicts 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 model cannot be used to explain local phenomena, it sheds light on the internal structure invoked in explanations of localized features and activities.

  14. A 1D plug flow reactor as validation tool for reactive transport simulations

    NASA Astrophysics Data System (ADS)

    Battaïa, G.; Garcia, D.

    2012-04-01

    Predictions in CO2 geological sequestration involve a broad range of earth sciences linked in complex models. Amongst the processes commonly described, fluid-rock interactions are both a central issue and a source of discomfort for modelers since it has to deal with 1) kinetics data obtained through experimental procedures that dramatically differ from natural systems and 2) reactive surface model that are very diverse and often empirical. This study presents a new type of plug flow reactor developed to provide an experimental validation of reactive transport simulations. This is a 1D pressurized packed-bed plug-flow reactor containing a granular mixture as a porous medium. This mixture is composed of a reactive solids and unreactive quartz used to set an adequate ratio between fluid and reactive mineral to control the front velocity. A seven sampling valve unit allows concentration profiles of the reacting fluid to be captured at any time. One the one side, a low reaction rate (diopside, HNO3, pH 2) produces linear profile resulting from a constant dissolution rate along the reactor length. But on the other side, when performing the reaction of CO2 saturated solutions (5 bar) at 40°C with dolomite it gives rise to dissolution fronts migrating downstream. A proper projection of experimental data reveals a dynamic steady state of front shape is reached. Texture of the mineral recovered at the end of the experiment is quantified by Hg-porosimetry and these results are linked to SEM observations. Altogether, this provides a robust way for the parameterization of a reactive surface area model.

  15. Beamforming of Ultrasound Signals from 1-D and 2-D Arrays under Challenging Imaging Conditions

    NASA Astrophysics Data System (ADS)

    Jakovljevic, Marko

    Beamforming of ultrasound signals in the presence of clutter, or partial aperture blockage by an acoustic obstacle can lead to reduced visibility of the structures of interest and diminished diagnostic value of the resulting image. We propose new beamforming methods to recover the quality of ultrasound images under such challenging conditions. Of special interest are the signals from large apertures, which are more susceptible to partial blockage, and from commercial matrix arrays that suffer from low sensitivity due to inherent design/hardware limitations. A coherence-based beamforming method designed for suppressing the in vivo clutter, namely Short-lag Spatial Coherence (SLSC) Imaging, is first implemented on a 1-D array to enhance visualization of liver vasculature in 17 human subjects. The SLSC images show statistically significant improvements in vessel contrast and contrast-to-noise ratio over the matched B-mode images. The concept of SLSC imaging is then extended to matrix arrays, and the first in vivo demonstration of volumetric SLSC imaging on a clinical ultrasound system is presented. The effective suppression of clutter via volumetric SLSC imaging indicates it could potentially compensate for the low sensitivity associated with most commercial matrix arrays. The rest of the dissertation assesses image degradation due to elements blocked by ribs in a transthoracic scan. A method to detect the blocked elements is demonstrated using simulated, ex vivo, and in vivo data from the fully-sampled 2-D apertures. The results show that turning off the blocked elements both reduces the near-field clutter and improves visibility of anechoic/hypoechoic targets. Most importantly, the ex vivo data from large synthetic apertures indicates that the adaptive weighing of the non-blocked elements can recover the loss of focus quality due to periodic rib structure, allowing large apertures to realize their full resolution potential in transthoracic ultrasound.

  16. A User's Guide to AMR1D: An Instructional Adaptive Mesh Refinement Code for Unstructured Grids

    NASA Technical Reports Server (NTRS)

    deFainchtein, Rosalinda

    1996-01-01

    This report documents the code AMR1D, which is currently posted on the World Wide Web (http://sdcd.gsfc.nasa.gov/ESS/exchange/contrib/de-fainchtein/adaptive _mesh_refinement.html). AMR1D is a one-dimensional finite element fluid-dynamics solver, capable of adaptive mesh refinement (AMR). It was written as an instructional tool for AMR on unstructured mesh codes. It is meant to illustrate the minimum requirements for AMR on more than one dimension. For that purpose, it uses the same type of data structure that would be necessary on a two-dimensional AMR code (loosely following the algorithm described by Lohner).

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

    PubMed

    Bauer, Wolfgang; Lochenie, Charles; Weber, Birgit

    2014-02-07

    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.

  18. DOPEX-1D2C: A one-dimensional, two-constraint radiation shield optimization code

    NASA Technical Reports Server (NTRS)

    Lahti, G. P.

    1973-01-01

    A one-dimensional, two-constraint radiation sheild weight optimization procedure and a computer program, DOPEX-1D2C, is described. The DOPEX-1D2C uses the steepest descent method to alter a set of initial (input) thicknesses of a spherical shield configuration to achieve a minimum weight while simultaneously satisfying two dose-rate constraints. The code assumes an exponential dose-shield thickness relation with parameters specified by the user. Code input instruction, a FORTRAN-4 listing, and a sample problem are given. Typical computer time required to optimize a seven-layer shield is less than 1/2 minute on an IBM 7094.

  19. Column Testing and 1D Reactive Transport Modeling to Evaluate Uranium Plume Persistence Processes

    SciTech Connect

    Johnson, Raymond H.; Morrison, Stan; Morris, Sarah; Tigar, Aaron; Dam, William; Dayvault, Jalena

    2016-04-26

    Motivation for Study: Natural flushing of contaminants at various U.S. Department of Energy Office of Legacy Management sites is not proceeding as quickly as predicted (plume persistence) Objectives: Help determine natural flushing rates using column tests. Use 1D reactive transport modeling to better understand the major processes that are creating plume persistence Approach: Core samples from under a former mill tailings area Tailings have been removed. Column leaching using lab-prepared water similar to nearby Gunnison River water. 1D reactive transport modeling to evaluate processes

  20. 1-D transient numerical model of a regenerator in a novel sub Kelvin Active Magnetic Regenerative Refrigerator

    NASA Astrophysics Data System (ADS)

    Jahromi, Amir E.; Miller, Franklin K.

    2016-03-01

    A sub Kelvin Active Magnetic Regenerative Refrigerator (AMRR) is being developed at the University of Wisconsin - Madison. This AMRR consists of two circulators, two regenerators, one superleak, one cold heat exchanger, and two warm heat exchangers. The circulators are novel non-moving part pumps that reciprocate a superfluid mixture of 4He-3He in the system. Heat from the mixture is removed within the two regenerators of this tandem system. An accurate model of the regenerators in this AMRR is necessary in order to predict the performance of these components, which in turn helps predicting the overall performance of the AMRR system. This work presents modeling methodology along with results from a 1-D transient numerical model of the regenerators of an AMRR capable of removing 2.5 mW at 850 mK at cyclic steady state.

  1. Building dictionaries of 1D and 3D motifs by mining the Unaligned 1D sequences of 17 archaeal and bacterial genomes.

    PubMed

    Rigoutsos, I; Gao, Y; Floratos, A; Parida, L

    1999-01-01

    We have used the Teiresias algorithm to carry out unsupervised pattern discovery in a database containing the unaligned ORFs from the 17 publicly available complete archaeal and bacterial genomes and build a 1D dictionary of motifs. These motifs which we refer to as seqlets account for and cover 97.88% of this genomic input at the level of amino acid positions. Each of the seqlets in this 1D dictionary was located among the sequences in Release 38.0 of the Protein Data Bank and the structural fragments corresponding to each seqlet's instances were identified and aligned in three dimensions: those of the seqlets that resulted in RMSD errors below a pre-selected threshold of 2.5 Angstroms were entered in a 3D dictionary of structurally conserved seqlets. These two dictionaries can be thought of as cross-indices that facilitate the tackling of tasks such as automated functional annotation of genomic sequences, local homology identification, local structure characterization, comparative genomics, etc.

  2. 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

  3. Fluctuations of Hyperglycemia and Insulin Sensitivity Are Linked to Menstrual Cycle Phases in Women With T1D

    PubMed Central

    Brown, Sue A.; Jiang, Boyi; McElwee-Malloy, Molly; Wakeman, Christian; Breton, Marc D.

    2015-01-01

    Background: Factors influencing glycemic variability in type 1 diabetes (T1D) may play a significant role in the refinement of closed loop insulin administration. Phase of menstrual cycle is one such factor that has been inadequately investigated. We propose that unique individual patterns can be constructed and used as parameters of closed loop systems. Method: Women with T1D on continuous subcutaneous insulin infusion and continuous glucose monitoring were studied for 3 consecutive menstrual cycles. Ovulation prediction kits and labs were used to confirm phase of menstrual cycle. Glycemic risks were assessed using the low- and high blood glucose indices (LBGI and HBGI). Insulin sensitivity (SI) was estimated using a Kalman filtering method from meal and insulin data. Overall change significance for glycemic risks was assessed by repeated measures ANOVA, with specific phases emphasized using contrasts. Results: Ovulation was confirmed in 33/36 cycles studied in 12 subjects (age = 33.1 ± 7.0 years, BMI = 25.7 ± 2.9 kg/m2, A1c = 6.8 ± 0.7%). Risk for hyperglycemia changed significantly during the cycle (P = .023), with HBGI increasing until early luteal phase and returning to initial levels thereafter. LBGI was steady in the follicular phase, decreasing thereafter but not significantly. SI was depressed during the luteal phase when compared to the early follicular phase (P ≤ .05). Total daily insulin, carbohydrates, or calories did not show any significant fluctuations. Conclusions: Women with T1D have glycemic variability changes that are specific to the individual and are linked to phase of cycle. An increased risk of hyperglycemia was observed during periovulation and early luteal phases compared to the early follicular phase; these changes appear to be associated with decreased insulin sensitivity during the luteal phase. PMID:26468135

  4. Exponents of the spectral functions and dynamical structure factor of the 1D Lieb-Liniger Bose gas

    NASA Astrophysics Data System (ADS)

    Carmelo, J. M. P.; Sacramento, P. D.

    2016-06-01

    We study the (k , ω) -plane finite-energy line shape of the zero-temperature one-boson removal spectral function (ω < 0) , one-boson addition spectral function (ω > 0) , and charge dynamical structure factor (ω > 0) of the 1D Lieb-Liniger Bose gas with repulsive boson interaction c > 0. Our analysis of the problem focuses on the line shape at finite excitation energies in the vicinity of these functions spectrum upper (ω < 0) or lower (ω > 0) threshold. Specifically, we derive the exact momentum, interaction, and density dependences of the exponents controlling such a line shape in each of the N = 1 , 2 , 3 , … momentum subdomains k ∈ [(N - 1) 2 πn , N 2 πn ] . Here n = N / L is the boson density, N the boson number, and L the system length. In the thermodynamic limit considered in our study nearly all spectral weight of the dynamical correlation functions is for large values of n / c contained in the N = 1 momentum subdomain k ∈ [ 0 , 2 πn ] . As n / c decreases a small fraction of that weight is transferred to the remaining set of N = 2 , 3 , 4 , … momentum subdomains, particularly to the N = 2 subdomain. In the case of the momentum subdomain k ∈ [ 0 , 2 πn ] , our exact results agree with those of previous studies. For that subdomain the above exponents are plotted as a function of the momentum for several n / c values. Our derivation of the line shapes of the three dynamical correlation functions relies on the use of a simplified form of the pseudofermion dynamical theory of the fermionic 1D Hubbard model suitably modified in this paper for the 1D Bose gas.

  5. Advanced Fuel Cycle Initiative AFC-1D, AFC-1G and AFC-1H End of FY-06 Irradiation Report

    SciTech Connect

    Advanced Fuel Cycle Initiative AFC-1D, AFC-1G and

    2006-09-01

    The U. S. Advanced Fuel Cycle Initiative (AFCI) seeks to develop and demonstrate the technologies needed to transmute the long-lived transuranic actinide isotopes contained in spent nuclear fuel into shorter-lived fission products, thereby dramatically decreasing the volume of material requiring disposition and the long-term radiotoxity and heat load of high-level waste sent to a geologic repository. The AFC-1 irradiation experiments on transmutation fuels are expected to provide irradiation performance data on non-fertile and low-fertile fuel forms specifically, irradiation growth and swelling, helium production, fission gas release, fission product and fuel constituent migration, fuel phase equilibria, and fuel-cladding chemical interaction. Contained in this report are the to-date physics evaluations performed on three of the AFC-1 experiments; AFC-1D, AFC-1G and AFC-1H. The AFC-1D irradiation experiment consists of metallic non-fertile fuel compositions with minor actinides for potential use in accelerator driven systems and AFC-1G and AFC-1H irradiation experiments are part of the fast neutron reactor fuel development effort. The metallic fuel experiments and nitride experiment are high burnup analogs to previously irradiated experiments and are to be irradiated to = 40 at.% burnup and = 25 at.% burnup, respectively. Based on the results of the physics evaluations it has been determined that the AFC-1D experiment will remain in the ATR for approximately 4 additional cycles, the AFC-1G experiment for an additional 4-5 cycles, and the AFC-1H experiment for approximately 8 additional cycles, in order to reach the desired programmatic burnup. The specific irradiation schedule for these tests will be determined based on future physics evaluations and all results will be documented in subsequent reports.

  6. On features of magnetization self-organization in 1D stochastic ferromagnetic systems

    NASA Astrophysics Data System (ADS)

    Ivanov, Anatoly A.; Orlov, Vitaly A.

    2017-03-01

    The magnetic structure of a polycrystalline nanowire at the weak or missing magnetostatic interaction exhibits the special self-organization of magnetization. As is known, the magnetization structure forming in a random crystallographic anisotropy field has a characteristic length range, which involves tens and hundreds of crystallites. This leads to the occurrence of stochastic domains. The induced uniform anisotropy of magnetostatic nature or the texture co-directed with the crystallite anisotropy axes masks the picture of stochastic domains. Nevertheless, as we show, the information on stochastic domains remains in the magnetization structure. The experimental techniques for obtaining information on the magnetic properties of stochastic domains are proposed.

  7. Quantum phase diagram of Polar Molecules in 1D Double Wire Systems

    NASA Astrophysics Data System (ADS)

    Chang, Chi-Ming; Wang, Daw-Wei

    2007-03-01

    We study the quantum phase transitions of fermionic polar molecules loaded in a double wire potential. By tuning the magnitude and direction of external electric field we observed many interesting quantum phases in different parameter range, including an easy-plane spin density wave, a triplet superconducting phase, and a truly long range order of easy-axis ferromagnetic phase in strong interacting regime. We also discuss how these exotic quantum phases can be measured in the existing experimental techniques.

  8. Magnetostriction and thermal expansion on 1D quantum spin system azurite

    SciTech Connect

    Fabris, Frederick W; Wolff-fabris, F; Francoual, S; Zapf, V; Jaime, M; Scott, B; Lacerda, A; Tozer, S; Hannahs, S; Murphy, T

    2008-01-01

    Recently the natural mineral Azurite has been proposed as model substance for the distorted S = 1/2 diamond chain in the spin fluid state. Azurite has alternating doublet monomers and singlet dimers along the chains yielding plateau-like features in the magnetization curves. Although Azurite was also reported to order antiferromagnetically at 1.86 K, the detailed phase diagram and its relationship to the 1/3 plateau is largely unknown. In the present paper, we report preliminary results from a dilatometry study on Azurite carried out in the 0.05--2.30 K temperature range at magnetic fields up to 31 T. It is shown that sizable structural distortions accompany the magnetic ordering and that at 100 mK the long range order between monomers is suppressed precisely at the transition field where the 1/3 plateau sets in.

  9. Verification of the Production Safe Flight Instrument Corporation OV/RV- 1D Stall Warning System

    DTIC Science & Technology

    1988-11-01

    Interchangeability, Louvered Scarfed Shroud Suppressor ( LSSS ). Prototype, Warning Margin 44 19. ABSTRACT (Continuo on niuese If necessar’y and Identify by block...conducted with the Louvered Scarfed Shroud Suppresser ( LSSS ) not installed clu toexessve ntne aceleand Tirewall temperatures previously encountered with...een (3rum- man’s test on airtraft/SN _67-18922 nd U.S. Army Aviation Engineering Flight Activity’s (AEFA’s) test on aircraft,. 62-5867 for LSSS not

  10. Application of the ITS2 Region for Barcoding Medicinal Plants of Selaginellaceae in Pteridophyta

    PubMed Central

    Gu, Wei; Song, Jingyuan; Cao, Yuan; Sun, Qingwen; Yao, Hui; Wu, Qinan; Chao, Jianguo; Zhou, Juanjuan; Xue, Wenda; Duan, Jinao

    2013-01-01

    Background Selaginellaceae is a family of nonseed plants with special evolutionary significance. Plants of the family Selaginellaceae are similarly shaped and easily confused, complicating identification via traditional methods. This study explored, for the first time, the use of the DNA barcode ITS2 to identify medicinal plants of the Selaginellaceae family. Methodology/Principal Findings In our study, 103 samples were collected from the main distribution areas in China; these samples represented 34 species and contained almost all of the medicinal plants of Selaginellaceae. The ITS2 region of the genome was amplified from these samples and sequenced using universal primers and reaction conditions. The success rates of the PCR amplification and sequencing were 100%. There was significant divergence between the interspecific and intraspecific genetic distances of the ITS2 regions, while the presence of a barcoding gap was obvious. Using the BLAST1 and nearest distance methods, our results proved that the ITS2 regions could successfully identify the species of all Selaginellaceae samples examined. In addition, the secondary structures of ITS2 in the helical regions displayed clear differences in stem loop number, size, position, and screw angle among the medicinal plants of Selaginellaceae. Furthermore, cluster analysis using the ITS2 barcode supported the relationship between the species of Selaginellaceae established by traditional morphological methods. Conclusion The ITS2 barcode can effectively identify medicinal plants of Selaginellaceae. The results provide a scientific basis for the precise identification of plants of the family Selaginellaceae and the reasonable development of these resources. This study may broaden the application of DNA barcoding in the medicinal plant field and benefit phylogenetic investigations. PMID:23826345

  11. On the extrema of a nonconvex functional with double-well potential in 1D

    NASA Astrophysics Data System (ADS)

    Gao, David Yang; Lu, Xiaojun

    2016-06-01

    This paper mainly investigates the extrema of a nonconvex functional with double-well potential in 1D through the approach of nonlinear differential equations. Based on the canonical duality method, the corresponding Euler-Lagrange equation with Neumann boundary condition can be converted into a cubic dual algebraic equation, which will help find the local extrema for the primal problem.

  12. Structural and mechanistic insights into regulation of the retromer coat by TBC1d5

    PubMed Central

    Jia, Da; Zhang, Jin-San; Li, Fang; Wang, Jing; Deng, Zhihui; White, Mark A.; Osborne, Douglas G.; Phillips-Krawczak, Christine; Gomez, Timothy S.; Li, Haiying; Singla, Amika; Burstein, Ezra; Billadeau, Daniel D.; Rosen, Michael K.

    2016-01-01

    Retromer is a membrane coat complex that is recruited to endosomes by the small GTPase Rab7 and sorting nexin 3. The timing of this interaction and consequent endosomal dynamics are thought to be regulated by the guanine nucleotide cycle of Rab7. Here we demonstrate that TBC1d5, a GTPase-activating protein (GAP) for Rab7, is a high-affinity ligand of the retromer cargo selective complex VPS26/VPS29/VPS35. The crystal structure of the TBC1d5 GAP domain bound to VPS29 and complementary biochemical and cellular data show that a loop from TBC1d5 binds to a conserved hydrophobic pocket on VPS29 opposite the VPS29–VPS35 interface. Additional data suggest that a distinct loop of the GAP domain may contact VPS35. Loss of TBC1d5 causes defective retromer-dependent trafficking of receptors. Our findings illustrate how retromer recruits a GAP, which is likely to be involved in the timing of Rab7 inactivation leading to membrane uncoating, with important consequences for receptor trafficking. PMID:27827364

  13. 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.

  14. 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

  15. 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.

  16. Characterization of 5-HT1D receptor binding sites in post-mortem human brain cortex.

    PubMed Central

    Martial, J; de Montigny, C; Cecyre, D; Quirion, R

    1991-01-01

    The present study provides further evidence for the presence of serotonin1D (5-HT1D) receptors in post-mortem human brain. Receptor binding parameters in temporal cortex homogenates were assessed using [3H]5-HT in the presence of 100 nM 8-OH-DPAT, 1 microM propranolol and 1 microM mesulergine to prevent labelling of the 5-HT1A, 5-HT1B and 5-HT1C sites, respectively. Under these conditions, [3H]5-HT apparently bound to a class of high affinity (Kd = 5.0 +/- 1.0 nM) low capacity (Bmax = 96 +/- 23 fmol/mg protein) sites. In competition experiments, 5-HT and 5-carboxyamidotryptamine (5-CT), as well as ergotamine, lysergic acid, sumatriptan and RU-24969 exhibited high affinity for these sites. This pharmacological profile is concordant with the ligand selectivity pattern reported for 5-HT1D receptors in other species and thus provides further evidence for its existence in human temporal cortex. In addition, the competition profile of some ligands, particularly of unlabelled 5-HT, 5-CT and ergotamine, revealed the existence of a lower affinity binding site. The latter suggests receptor heterogeneity or the presence of a lower affinity state of 5-HT1D receptors. PMID:1911737

  17. Sensitivity of quantum yield for O(/sup 1/D) production from ozone photolysis

    SciTech Connect

    Wuebbles, D.J.; Tarp, R.L.

    1980-06-01

    Recent laboratory studies have indicated that the quantum yield for O(/sup 1/D) production from photolysis of ozone may be less than unity at wavelengths shorter than 300 nm (below the fall off region). Previously it had been assumed that the quantum yield was unity at these wavelengths. Based on the recent work of Brock and Watson (who measured the quantum yield at 266 nm), the effect of assuming a quantum yield of 0.9 for O(/sup 1/D) production at wavelengths less than 300 nm in the LLL 1-d model was tested. Since measurements of the quantum yield fall off at longer wavelength also assume unity quantum yield below the fall off region, we also multiplied the O(/sup 1/D) quantum yield through this region by 0.9. The remaining quantum yield from the photolysis reaction is assumed to produce O(/sup 3/P) at all wavelengths so that the total quantum yield is unity.

  18. Classical solution to 1D viscous polytropic perfect fluids with constant diffusion coefficients and vacuum

    NASA Astrophysics Data System (ADS)

    Liang, Zhilei; Wu, Shanqiu

    2017-02-01

    This paper deals with the initial boundary value problem for one-dimensional (1D) viscous, compressible and heat conducting fluids. We establish the global existence and uniqueness of classical solutions, with large data and possible vacuum at initial time. Our approach is based on the Calderón-Zygmund decomposition technique and allows that the viscosity and heat conductivity are both constant.

  19. [Biodegradation characteristics of o-chlorophenol with photosynthetic bacteria PSB-1D].

    PubMed

    Hu, Xiao-min; Dong, Yi-hu; Li, Liang; Lu, Juan; He, Ying-dian; Gao, Yang

    2010-07-01

    A strain of photosynthetic bacteria named PSB-1D with degradation of o-chlorophenol (2-CP) was isolated and screened from the shallow substrate sludge in downstream side of the sewage outfall of an insecticide factory. The PSB-1D is identified preliminarily as Rhodopseudomonas sp. according to its colony and cell morphological properties, physiological biochemical characteristics and absorption spectrum analysis of living cells. The experiments results of relationship between PSB-1D growth and o-chlorophenol degradation showed that the degradation rate of o-chlorophenol was up to 57.26% after 7 days cultural time. The main environmental factors including way of illumination and oxygen, initial pH, cultural temperature, illumination intensity had distinctly influenced on the o-chlorophenol degradation with PSB-1D. The results showed that the optimum conditions were as following: an anaerobic light, pH 7.0, temperature 30 degrees C, illumination intensity 4000 lx,initial o-chlorophenol concentration 50 mg/L. Under that cultural condition, the degradation rate of o-chlorophenol could reach to 62.08%. The degradation kinetic data fitted the Andrews model well. In addition, the biodegradation process of o-chlorophenol can be well described by enzymatic reaction of high concentration inhibition, with the maximum substrate utilization rate 0.309 d(-1), Michaelis-Menten constant 2.733 mg/L, inhibitory constant 230.15 mg/L respectively.

  20. Fluctuation of Density of States for 1d Schrödinger Operators

    NASA Astrophysics Data System (ADS)

    Nakano, Fumihiko

    2017-03-01

    We consider the 1d Schrödinger operator with random decaying potential and compute the 2nd term asymptotics of the density of states, which shows substantial differences between the cases α > 1/2, α < 1/2 and α = 1/2.

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

    PubMed Central

    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

    2016-01-01

    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

  2. Medulloblastoma expresses CD1d and can be targeted for immunotherapy with NKT cells.

    PubMed

    Liu, Daofeng; Song, Liping; Brawley, Vita S; Robison, Nathan; Wei, Jie; Gao, Xiuhua; Tian, Gengwen; Margol, Ashley; Ahmed, Nabil; Asgharzadeh, Shahab; Metelitsa, Leonid S

    2013-10-01

    Medulloblastoma (MB) is the most common malignant brain tumor of childhood. Current therapies are toxic and not always curative that necessitates development of targeted immunotherapy. However, little is known about immunobiology of this tumor. In this study, we show that MB cells in 9 of 20 primary tumors express CD1d, an antigen-presenting molecule for Natural Killer T cells (NKTs). Quantitative RT-PCR analysis of 61 primary tumors revealed an elevated level of CD1d mRNA expression in a molecular subgroup characterized by an overactivation of Sonic Hedgehog (SHH) oncogene compared with Group 4. CD1d-positive MB cells cross-presented glycolipid antigens to activate NKT-cell cytotoxicity. Intracranial injection of NKTs resulted in regression of orthotopic MB xenografts in NOD/SCID mice. Importantly, the numbers and function of peripheral blood type-I NKTs were preserved in MB patients. Therefore, CD1d is expressed on tumor cells in a subset of MB patients and represents a novel target for immunotherapy.

  3. Ckmeans.1d.dp: Optimal k-means Clustering in One Dimension by Dynamic Programming.

    PubMed

    Wang, Haizhou; Song, Mingzhou

    2011-12-01

    The heuristic k-means algorithm, widely used for cluster analysis, does not guarantee optimality. We developed a dynamic programming algorithm for optimal one-dimensional clustering. The algorithm is implemented as an R package called Ckmeans.1d.dp. We demonstrate its advantage in optimality and runtime over the standard iterative k-means algorithm.

  4. Accuracy of 1D microvascular flow models in the limit of low Reynolds numbers.

    PubMed

    Pindera, Maciej Z; Ding, Hui; Athavale, Mahesh M; Chen, Zhijian

    2009-05-01

    We describe results of numerical simulations of steady flows in tubes with branch bifurcations using fully 3D and reduced 1D geometries. The intent is to delineate the range of validity of reduced models used for simulations of flows in microcapillary networks, as a function of the flow Reynolds number Re. Results from model problems indicate that for Re less than 1 and possibly as high as 10, vasculatures may be represented by strictly 1D Poiseuille flow geometries with flow variation in the axial dimensions only. In that range flow rate predictions in the different branches generated by 1D and 3D models differ by a constant factor, independent of Re. When the cross-sectional areas of the branches are constant these differences are generally small and appear to stem from an uncertainty of how the individual branch lengths are defined. This uncertainty can be accounted for by a simple geometrical correction. For non-constant cross-sections the differences can be much more significant. If additional corrections for the presence of branch junctions and flow area variations are not taken into account in 1D models of complex vasculatures, the resultant flow predictions should be interpreted with caution.

  5. Complex-coordinate calculation of 1D(e) resonances using Hylleraas functions

    NASA Technical Reports Server (NTRS)

    Bhatia, A. K.; Ho, Y. K.

    1990-01-01

    The lowest 1D(e) resonances below the n = 2 and n = 3 thresholds are calculated using a method of complex-coordinate rotation. The results, obtained with the use of Hylleraas functions, are believed to be of high accuracy. This work should serve as a useful reference for other investigations.

  6. Interfacing the NRL 1-D High Vertical Resolution Aerosol Model with COAMPS

    DTIC Science & Technology

    2016-06-13

    TERM GOALS Identify, understand and quantify all the physical processes that govern the aerosols in the marine environment and develop a...size and composition distributions are required. Many of the aerosol source, sink and transformation processes are highly dependent on meteorological...parameters such as wind speed, humidity profile, clouds, precipitation scavenging, etc. The NRL 1-D aerosol- processes model includes all these

  7. 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.

  8. 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

    2016-02-05

    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.

  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. CAMK1D amplification implicated in epithelial-mesenchymal transition in basal-like breast cancer.

    PubMed

    Bergamaschi, Anna; Kim, Young H; Kwei, Kevin A; La Choi, Yoon; Bocanegra, Melanie; Langerød, Anita; Han, Wonshik; Noh, Dong-Young; Huntsman, David G; Jeffrey, Stefanie S; Børresen-Dale, Anne-Lise; Pollack, Jonathan R

    2008-12-01

    Breast cancer exhibits clinical and molecular heterogeneity, where expression profiling studies have identified five major molecular subtypes. The basal-like subtype, expressing basal epithelial markers and negative for estrogen receptor (ER), progesterone receptor (PR) and HER2, is associated with higher overall levels of DNA copy number alteration (CNA), specific CNAs (like gain on chromosome 10p), and poor prognosis. Discovering the molecular genetic basis of tumor subtypes may provide new opportunities for therapy. To identify the driver oncogene on 10p associated with basal-like tumors, we analyzed genomic profiles of 172 breast carcinomas. The smallest shared region of gain spanned just seven genes at 10p13, including calcium/calmodulin-dependent protein kinase ID (CAMK1D), functioning in intracellular signaling but not previously linked to cancer. By microarray, CAMK1D was overexpressed when amplified, and by immunohistochemistry exhibited elevated expression in invasive carcinomas compared to carcinoma in situ. Engineered overexpression of CAMK1D in non-tumorigenic breast epithelial cells led to increased cell proliferation, and molecular and phenotypic alterations indicative of epithelial-mesenchymal transition (EMT), including loss of cell-cell adhesions and increased cell migration and invasion. Our findings identify CAMK1D as a novel amplified oncogene linked to EMT in breast cancer, and as a potential therapeutic target with particular relevance to clinically unfavorable basal-like tumors.

  11. 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.

  12. 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.

  13. Controlled way to prepare quasi-1D nanostructures with complex chemical composition in porous anodic alumina.

    PubMed

    Lukatskaya, Maria R; Trusov, Lev A; Eliseev, Andrey A; Lukashin, Alexey V; Jansen, Martin; Kazin, Pavel E; Napolskii, Kirill S

    2011-02-28

    Herein we propose a novel approach to the preparation of quasi-1D nanostructures with various chemical compositions based on infiltration of colloidal solution into the asymmetric anodic alumina membrane. The proposed technique was successfully applied for the preparation of ordered arrays of the magnetically hard anisotropic hexaferrite nanostructures.

  14. HYDRUS-1D Modeling of an Irrigated Agricultural Plot with Application to Aquifer Recharge Estimation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A variety of methods are available for estimating aquifer recharge in semi-arid regions, each with advantages and disadvantages. We are investigating a procedure for estimating recharge in an irrigated basin. The method involves computing irrigation return flows based on HYDRUS-1D modeling of root z...

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

    NASA Astrophysics Data System (ADS)

    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.

  17. Role of α1D -adrenoceptors in vascular wall hypertrophy during angiotensin II-induced hypertension.

    PubMed

    Gallardo-Ortíz, I A; Rodríguez-Hernández, S N; López-Guerrero, J J; Del Valle-Mondragón, L; López-Sánchez, P; Touyz, R M; Villalobos-Molina, R

    2015-09-01

    The in vivo effect of continuous angiotensin II (Ang II) infusion on arterial blood pressure, vascular hypertrophy and α1 -adrenoceptors (α1 -ARs) expression was explored. Alzet(®) minipumps filled with Ang II (200 ng kg(-1)  min(-1) ) were subcutaneously implanted in male Wistar rats (3 months-old). Groups of rats were also treated with losartan, an AT1 R antagonist, or with BMY 7378, a selective α1D -AR antagonist. Blood pressure was measured by tail-cuff; after 2 or 4 weeks of treatment, vessels were isolated for functional and structural analyses. Angiotensin II increased systolic blood pressure. Phenylephrine-induced contraction in aorta was greater (40% higher) in Ang II-treated rats than in the controls, and similar effect occurred with KCl 80 mm. Responses in tail arteries were not significantly different among the different groups. Angiotensin II decreased α1D -ARs without modifying the other α1 -ARs and induced an increase in media thickness (hypertrophy) in aorta, while no structural change occurred in tail artery. Losartan prevented and reversed hypertension and hypertrophy, while BMY 7378 prevented and reversed the aorta's hypertrophic response, without preventing or reversing hypertension. Findings indicate that Ang II-induced aortic hypertrophic response involves Ang II-AT1 Rs and α1D -ARs. Angiotensin II-induced α1D -AR-mediated vascular remodeling occurs independently of hypertension. Findings identify a α1D -AR-mediated process whereby Ang II influences aortic hypertrophy independently of blood pressure elevation.

  18. Improvement of the 2D/1D Method in MPACT Using the Sub-Plane Scheme

    SciTech Connect

    Graham, Aaron M; Collins, Benjamin S; Downar, Thomas

    2017-01-01

    Oak Ridge National Laboratory and the University of Michigan are jointly developing the MPACTcode to be the primary neutron transport code for the Virtual Environment for Reactor Applications (VERA). To solve the transport equation, MPACT uses the 2D/1D method, which decomposes the problem into a stack of 2D planes that are then coupled with a 1D axial calculation. MPACT uses the Method of Characteristics for the 2D transport calculations and P3 for the 1D axial calculations, then accelerates the solution using the 3D Coarse mesh Finite Dierence (CMFD) method. Increasing the number of 2D MOC planes will increase the accuracy of the alculation, but will increase the computational burden of the calculations and can cause slow convergence or instability. To prevent these problems while maintaining accuracy, the sub-plane scheme has been implemented in MPACT. This method sub-divides the MOC planes into sub-planes, refining the 1D P3 and 3D CMFD calculations without increasing the number of 2D MOC planes. To test the sub-plane scheme, three of the VERA Progression Problems were selected: Problem 3, a single assembly problem; Problem 4, a 3x3 assembly problem with control rods and pyrex burnable poisons; and Problem 5, a quarter core problem. These three problems demonstrated that the sub-plane scheme can accurately produce intra-plane axial flux profiles that preserve the accuracy of the fine mesh solution. The eigenvalue dierences are negligibly small, and dierences in 3D power distributions are less than 0.1% for realistic axial meshes. Furthermore, the convergence behavior with the sub-plane scheme compares favorably with the conventional 2D/1D method, and the computational expense is decreased for all calculations due to the reduction in expensive MOC calculations.

  19. Combined crossed beam and theoretical studies of the C(1D) + CH4 reaction

    NASA Astrophysics Data System (ADS)

    Leonori, Francesca; Skouteris, Dimitrios; Petrucci, Raffaele; Casavecchia, Piergiorgio; Rosi, Marzio; Balucani, Nadia

    2013-01-01

    The reaction involving atomic carbon in its first electronically excited state 1D and methane has been investigated in crossed molecular beam experiments at a collision energy of 25.3 kJ mol-1. Electronic structure calculations of the underlying potential energy surface (PES) and Rice-Ramsperger-Kassel-Marcus (RRKM) estimates of rates and branching ratios have been performed to assist the interpretation of the experimental results. The reaction proceeds via insertion of C(1D) into one of the C-H bonds of methane leading to the formation of the intermediate HCCH3 (methylcarbene or ethylidene), which either decomposes directly into the products C2H3 + H or C2H2 + H2 or isomerizes to the more stable ethylene, which in turn dissociates into C2H3 + H or H2CC + H2. The experimental results indicate that the H-displacement and H2-elimination channels are of equal importance and that for both channels the reaction mechanism is controlled by the presence of a bound intermediate, the lifetime of which is comparable to its rotational period. On the contrary, RRKM estimates predict a very short lifetime for the insertion intermediate and the dominance of the H-displacement channel. It is concluded that the reaction C(1D) + CH4 cannot be described statistically and a dynamical treatment is necessary to understand its mechanism. Possibly, nonadiabatic effects are responsible for the discrepancies, as triplet and singlet PES of methylcarbene cross each other and intersystem crossing is possible. Similarities with the photodissociation of ethylene and with the related reactions N(2D) + CH4, O(1D) + CH4 and S(1D) + CH4 are also commented on.

  20. Adjoint Method and Predictive Control for 1-D Flow in NASA Ames 11-Foot Transonic Wind Tunnel

    NASA Technical Reports Server (NTRS)

    Nguyen, Nhan; Ardema, Mark

    2006-01-01

    This paper describes a modeling method and a new optimal control approach to investigate a Mach number control problem for the NASA Ames 11-Foot Transonic Wind Tunnel. The flow in the wind tunnel is modeled by the 1-D unsteady Euler equations whose boundary conditions prescribe a controlling action by a compressor. The boundary control inputs to the compressor are in turn controlled by a drive motor system and an inlet guide vane system whose dynamics are modeled by ordinary differential equations. The resulting Euler equations are thus coupled to the ordinary differential equations via the boundary conditions. Optimality conditions are established by an adjoint method and are used to develop a model predictive linear-quadratic optimal control for regulating the Mach number due to a test model disturbance during a continuous pitch

  1. Validation of Sea Surface Temperature Retrieved from the MVISR sensor onboard the Chinese Feng Yun 1D Meteorological Satellite

    NASA Astrophysics Data System (ADS)

    Kamal, Mohammed; Cervone, Guido; Kafatos, M.

    The purpose of this paper is to use the Direct Broadcast (DB) system located on the George Mason University Fenwick Library, validating Sea Surface Temperature in National Oceanic and Atmospheric Administration (NOAA) - Advanced Very High Resolution Radiometer (AVHRR) and Chinese Feng Yun 1D (FY1D) - Multi-channel Visible and Infrared Scan Radiometer (MVISR) data sets. The MVISR sensor flying shares many similarities with the NOAA AVHRR sensor in terms of spatial, temporal and spectral resolutions, orbital position and data transmission. MVISR has twice the spectral resolution than the AVHRR sensor, employing 10 channels with wavelengths between .43 and 12.5 microns, covering the visible, near and thermal infrared parts of the electromagnetic spectrum. Measurements from the MVISR sensor have not been extensively investigated due to difficulties in obtaining data, lack of sensor calibration information and product generation algorithms. The current work presents a detailed comparison of Sea Surface Temperature calibrated data derived from channels 3, 4 and 5 were utilized for MVISR and AVHRR measurements from different regions along the Atlantic coast of the USA, and Gulf of Mexico. Cross calibration between AVHRR and MVISR measurements were performed. Values measured by MVISR are found to agree well with AVHRR measurements.

  2. Development of a 3D to 1D Particle Transport Model to Predict Deposition in the Lungs

    NASA Astrophysics Data System (ADS)

    Oakes, Jessica M.; Grandmont, Celine; Shadden, Shawn C.; Vignon-Clementel, Irene E.

    2014-11-01

    Aerosolized particles are commonly used for therapeutic drug delivery as they can be delivered to the body systemically or be used to treat lung diseases. Recent advances in computational resources have allowed for sophisticated pulmonary simulations, however it is currently impossible to solve for airflow and particle transport for all length and time scales of the lung. Instead, multi-scale methods must be used. In our recent work, where computational methods were employed to solve for airflow and particle transport in the rat airways (Oakes et al. (2014), Annals of Biomedical Engineering 42, 899), the number of particles to exit downstream of the 3D domain was determined. In this current work, the time-dependent Lagrangian description of particles was used to numerically solve a 1D convection-diffusion model (trumpet model, Taulbee and Yu (1975), Journal of Applied Physiology, 38, 77) parameterized specifically for the lung. The expansion of the airway dimensions was determined based on data collected from our aerosol exposure experiments (Oakes et al. (2014), Journal of Applied Physiology, 116, 1561). This 3D-1D framework enables us to predict the fate of particles in the whole lung. This work was supported by the Whitaker Foundation at the IIE, a INRIA Associated Team Postdoc Grant, and a UC Presidential Fellowship.

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

    PubMed Central

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

    2015-01-01

    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

  4. 1D Runoff-runon stochastic model in the light of queueing theory : heterogeneity and connectivity

    NASA Astrophysics Data System (ADS)

    Harel, M.-A.; Mouche, E.; Ledoux, E.

    2012-04-01

    Runoff production on a hillslope during a rainfall event may be simplified as follows. Given a soil of constant infiltrability I, which is the maximum amount of water that the soil can infiltrate, and a constant rainfall intensity R, runoff is observed where R is greater than I. The infiltration rate equals the infiltrability when runoff is produced, R otherwise. When ponding time, topography, and overall spatial and temporal variations of physical parameters, such as R and I, are neglected, the runoff equation remains simple. In this study, we consider soils of spatially variable infiltrability. As runoff can re-infiltrate on down-slope areas of higher infiltrabilities (runon), the resulting process is highly non-linear. The stationary runoff equation is: Qn+1 = max(Qn + (R - In)*Δx , 0) where Qn is the runoff arriving on pixel n of size Δx [L2/T], R and In the rainfall intensity and infiltrability on that same pixel [L/T]. The non-linearity is due to the dependence of infiltration on R and Qn, that is runon. This re-infiltration process generates patterns of runoff along the slope, patterns that organise and connect to each other differently depending on the rainfall intensity and the nature of the soil heterogeneity. The runoff connectivity, assessed using the connectivity function of Allard (1993), affects greatly the dynamics of the runoff hillslope. Our aim is to assess, in a stochastic framework, the runoff organization on 1D slopes with random infiltrabilities (log-normal, exponential, bimodal and uniform distributions) by means of theoretical developments and numerical simulations. This means linking the nature of soil heterogeneity with the resulting runoff organisation. In term of connectivity, we investigate the relations between structural (infiltrability) and functional (runoff) connectivity. A theoretical framework based on the queueing theory is developed. We implement the idea of Jones et al. (2009), who remarked that the above formulation is

  5. Loss-of-Function of hNav1.5 by ZASP1-D117N Associated with Intraventricular Conduction Disturbances in Left Ventricular Noncompaction

    PubMed Central

    Xi, Yutao; Ai, Tomohiko; De Lange, Enno; Li, Zhaohui; Wu, Geru; Brunelli, Luca; Kyle, W. Buck; Turker, Isik; Cheng, Jie; Ackerman, Michael J.; Kimura, Akinori; Weiss, James N.; Qu, Zhilin; Kim, Jeffrey J.; Faulkner, Georgine; Vatta, Matteo

    2013-01-01

    Background Defects of cytoarchitectural proteins can cause left ventricular noncompaction (LVNC), which is often associated with conduction system diseases. We have previously identified a p.D117N mutation in the LDB3-encoding Z-band Alternatively Spliced PDZ motif gene (ZASP) in a patient with LVNC and conduction disturbances. We sought to investigate a role of p.D117N mutation in the LBD3 NM_001080114.1 isoform (ZASP1-D117N) in the regulation of cardiac sodium channel (Nav1.5) that plays an important role in the cardiac conduction system. Methods and Results Effects of ZASP1-wt and ZASP1-D117N on Nav1.5 were studied in HEK-293 cells and neonatal rat cardiomyocytes (NRCMs). Patch-clamp study demonstrated that ZASP1-D117N significantly attenuated INa by 27% in HEK-293 cells and by 32% in NRCMs. In addition, ZASP1-D117N rightward shifted the voltage-dependent activation and inactivation in both systems. In silico simulation using Luo-Rudy phase 1 model demonstrated that altered Nav1.5 function can reduce cardiac conduction velocity by 28% compared to the control. Pull-down assays showed that both wt and ZASP1-D117N can complex with Nav1.5 and telethonin/T-Cap, which required intact PDZ domains. Immunohistochemical staining in NRCMs demonstrates that ZASP1-D117N did not significantly disturb the Z-line structure. Disruption of cytoskeletal networks with ML-7 and cytochalasin D abolished the effects of ZASP1-D117N on the Nav1.5. Conclusions ZASP1 can form protein complex with telethonin/T-Cap and Nav1.5. The LVNC-specific ZASP1 mutation can cause loss-of-function of Nav1.5 without significant alteration of the cytoskeletal protein complex. Our study suggests that electrical remodeling can occur in LVNC subject due to a direct effect of mutant ZASP on Nav1.5. PMID:22929165

  6. X(3872) as the {sup 1}D{sub 2} charmonium

    SciTech Connect

    Kalashnikova, Yu. S.; Nefediev, A. V.

    2013-12-15

    The {sup 1}D{sub 2} charmonium assignment for the X(3872) is considered, which is compatible with the 2{sup −+} quantum numbers, as favoured by the BABAR Collaboration analysis presented recently for the π{sup +}π{sup −}π{sup 0}J/ψ decay mode. It is demonstrated that established properties of the X(3872) are in a drastic conflict with the {sup 1}D{sub 2}c c-bar assignment. Furthermore, it is argued that a combined analysis of the data for different decay channels of the X, with the help of theoretical formulae which meet a number of constraints imposed by phenomenology, results in a suitable description of the experimental data for the X compatible with its quantum numbers 1{sup ++}.

  7. In silico analysis of protein Lys-N&#x1D700;-acetylation in plants

    PubMed Central

    Rao, R. Shyama Prasad; Thelen, Jay J.; Miernyk, Ján A.

    2014-01-01

    Among post-translational modifications, there are some conceptual similarities between Lys-N&#x1D700;-acetylation and Ser/Thr/Tyr O-phosphorylation. Herein we present a bioinformatics-based overview of reversible protein Lys-acetylation, including some comparisons with reversible protein phosphorylation. The study of Lys-acetylation of plant proteins has lagged behind studies of mammalian and microbial cells; 1000s of acetylation sites have been identified in mammalian proteins compared with only hundreds of sites in plant proteins. While most previous emphasis was focused on post-translational modifications of histones, more recent studies have addressed metabolic regulation. Being directly coupled with cellular CoA/acetyl-CoA and NAD/NADH, reversible Lys-N&#x1D700;-acetylation has the potential to control, or contribute to control, of primary metabolism, signaling, and growth and development. PMID:25136347

  8. 1D to 3D Crossover of a Spin-Imbalanced Fermi Gas

    NASA Astrophysics Data System (ADS)

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

    2016-12-01

    We have characterized the one-dimensional (1D) to three-dimensional (3D) crossover of a two-component spin-imbalanced Fermi gas of 6Li atoms in a 2D optical lattice by varying the lattice tunneling and the interactions. The gas phase separates, and we detect the phase boundaries using in situ imaging of the inhomogeneous density profiles. The locations of the phases are inverted in 1D as compared to 3D, thus providing a clear signature of the crossover. By scaling the tunneling rate t with respect to the pair binding energy ɛB, we observe a collapse of the data to a universal crossover point at a scaled tunneling value of t˜c=0.025 (7 ).

  9. 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.

  10. A novel coordination polymer containing both interdigitated 1D chains and interpenetrated 2D grids.

    PubMed

    Ayyappan, Ponnaiyan; Evans, Owen R; Lin, Wenbin

    2002-07-01

    A hydro(solvo)thermal reaction between zinc perchlorate and ethyl ester of a new pyridinecarboxylate bridging ligand of approximately 17.6 A in length yields a unique coordination polymer which contains both interdigitated infinite 1D chains and interpenetrated 2D rhombohedral grids [Zn(2.5)(L)(4)(mu(3)-OH)] x (H(2)O)(5), 1, where L is 3-[[4-(4-pyridylethenyl)phenyl]ethenyl]benzoate. The 1D chains contain mu(3)-bridged hydroxy groups and have a [Zn(4)(mu(3)-OH)(2)(L)(6)] stoichiometry, while the 2D grids have a Zn(L)(2) formula and diagonal distances of 31.7 and 25.2 A. Crystal data for 1: monoclinic space group P2/c, a = 15.686(2) A, b = 12.6103(16) A, c = 38.999(5) A, beta = 98.397(2) degrees, and Z = 4.

  11. 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.

  12. 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.

  13. 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.

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

    SciTech Connect

    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.

  15. Constraint on the 1D earth model near core-mantle boundary by free core nutation

    NASA Astrophysics Data System (ADS)

    Huang, Chengli; Zhang, Mian

    2015-04-01

    Free core nutation (FCN) is a normal mode of the rotating earth with fluid outer core (FOC). Its period depends on the physics of the mantle and FOC, especially the parameters near core-mantle boundary (CMB), like the density and elastic (Lame) parameters. FCN period can be determined very accurately by VLBI and superconductive tidal gravimetry, but the theoretical calculation results of FCN period from traditional approaches and 1D earth model (like PREM) deviate significantly from the accurate observation. Meanwhile, the influence of the uncertainty of a given earth model on nutation has never been studied before. In this work, a numerical experiment is presented to check this problem, and we want to see whether FCN can provide a constraint on the construction of a 1D earth model, especially on the gradient of material density near CMB.

  16. Elucidation of the O(1D) + HF → F + OH mechanism by means of quasiclassical trajectories.

    PubMed

    Jambrina, P G; Montero, I; Aoiz, F J; Aldegunde, J; Alvariño, J M

    2012-12-21

    The dynamics and mechanism of the O((1)D) + HF → F + OH reaction have been studied through quasi-classical trajectory calculations carried out on the 1(1)A' Potential Energy Surface (PES) fitted by Gómez-Carrasco et al. [Chem. Phys. Lett., 2007, 435, 188]. The influence of the collision energy and the initial rovibrational state on the reaction has been considered. As a result of this study, we conclude that for v = 0 the reactive collisions take place exclusively through an indirect mechanism that involves a long-lived complex. Interestingly and somewhat unexpectedly for a barrierless reaction, vibrational excitation causes a large enhancement of the reactivity due to the concurrence of a direct abstraction mechanism. Unlike other reactions also taking place on a barrierless PES featuring deep wells, no insertion mechanism is observed in O((1)D) + HF reactive collisions.

  17. 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.

  18. 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.

  19. 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.

  20. Rogue-wave bullets in a composite (2+1)D nonlinear medium.

    PubMed

    Chen, Shihua; Soto-Crespo, Jose M; Baronio, Fabio; Grelu, Philippe; Mihalache, Dumitru

    2016-07-11

    We show that nonlinear wave packets localized in two dimensions with characteristic rogue wave profiles can propagate in a third dimension with significant stability. This unique behavior makes these waves analogous to light bullets, with the additional feature that they propagate on a finite background. Bulletlike rogue-wave singlet and triplet are derived analytically from a composite (2+1)D nonlinear wave equation. The latter can be interpreted as the combination of two integrable (1+1)D models expressed in different dimensions, namely, the Hirota equation and the complex modified Korteweg-de Vries equation. Numerical simulations confirm that the generation of rogue-wave bullets can be observed in the presence of spontaneous modulation instability activated by quantum noise.

  1. Regulation of Translation Factor EEF1D Gene Function by Alternative Splicing

    PubMed Central

    Kaitsuka, Taku; Matsushita, Masayuki

    2015-01-01

    Alternative splicing is an exquisite mechanism that allows one coding gene to have multiple functions. The alternative splicing machinery is necessary for proper development, differentiation and stress responses in a variety of organisms, and disruption of this machinery is often implicated in human diseases. Previously, we discovered a long form of eukaryotic elongation factor 1Bδ (eEF1Bδ; this long-form eEF1Bδ results from alternative splicing of EEF1D transcripts and regulates the cellular stress response by transcriptional activation, not translational enhancement, of heat-shock responsive genes. In this review, we discuss the molecular function of EEF1D alternative splicing products and the estimated implication of human diseases. PMID:25686034

  2. Quasi-1D Superfluids In A Spin-Imbalanced Fermi Gas

    NASA Astrophysics Data System (ADS)

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

    2015-05-01

    We experimentally study the phases of an ultracold two-spin component gas of atomic fermions (6Li) confined to 1D tubes formed by a 2D optical lattice. The atoms are prepared in the lowest two hyperfine sublevels where their interactions are tuned by a Feshbach resonance. We previously observed phase separation into a partially-polarized superfluid core and either fully-paired or fully-polarized wings (depending on the spin polarization). In 3D, the phase separation is inverted, such that the cloud center is fully paired. We investigate the transition from a 1D to 3D gas by varying the lattice depth and interaction strength which changes the ratio of the tunneling rate between the tubes to the pair binding energy. The region of parameter space we are exploring is believed to be the most promising region for the exotic FFLO superfluid phase. Supported by ARO, NSF, ONR, and the Welch Foundation.

  3. 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

  4. 1D and 2D simulations of seismic wave propagation in fractured media

    NASA Astrophysics Data System (ADS)

    Möller, Thomas; Friederich, Wolfgang

    2016-04-01

    Fractures and cracks have a significant influence on the propagation of seismic waves. Their presence causes reflections and scattering and makes the medium effectively anisotropic. We present a numerical approach to simulation of seismic waves in fractured media that does not require direct modelling of the fracture itself, but uses the concept of linear slip interfaces developed by Schoenberg (1980). This condition states that at an interface between two imperfectly bonded elastic media, stress is continuous across the interface while displacement is discontinuous. It is assumed that the jump of displacement is proportional to stress which implies a jump in particle velocity at the interface. We use this condition as a boundary condition to the elastic wave equation and solve this equation in the framework of a Nodal Discontinuous Galerkin scheme using a velocity-stress formulation. We use meshes with tetrahedral elements to discretise the medium. Each individual element face may be declared as a slip interface. Numerical fluxes have been derived by solving the 1D Riemann problem for slip interfaces with elastic and viscoelastic rheology. Viscoelasticity is realised either by a Kelvin-Voigt body or a Standard Linear Solid. These fluxes are not limited to 1D and can - with little modification - be used for simulations in higher dimensions as well. The Nodal Discontinuous Galerkin code "neXd" developed by Lambrecht (2013) is used as a basis for the numerical implementation of this concept. We present examples of simulations in 1D and 2D that illustrate the influence of fractures on the seismic wavefield. We demonstrate the accuracy of the simulation through comparison to an analytical solution in 1D.

  5. 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.

  6. Complete Measurement of S(1D2) Photofragment Alignment from Abel-Invertible Ion Images

    NASA Astrophysics Data System (ADS)

    Rakitzis, T. Peter; Samartzis, Peter C.; Kitsopoulos, Theofanis N.

    2001-09-01

    A novel method to measure directly the photofragment alignment from Abel-invertible two-dimensional ion images, as a function of photofragment recoil velocity, is demonstrated for S(1D2) atoms from the photodissociation of carbonyl sulfide at 223 nm. The results are analyzed in terms of coherent and incoherent contributions from two dissociative states, showing that the phase differences of the asymptotic wave functions of the fast and slow recoil-velocity channel are approximately π/2 and 0, respectively.

  7. 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.

  8. 1-D Heat Transfer in Multilayer Materials Using a Finite Volume Approach

    DTIC Science & Technology

    2014-01-01

    AEROSPACE REPORT NO. TR-2014-01128 1-D Heat Transfer in Multilayer Materials Using a Finite Volume Approach January 1, 2014 Marcus A...unlimited. The cost to prepare this document: $395 This report was submitted by The Aerospace Corporation, El Segundo...project officer for the Development Planning (XR) program. This report has been reviewed by the Public Affairs Office (PAS) and is releasable to the

  9. 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.

  10. 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.

  11. 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.

  12. A versatile compact model for ballistic 1D transistor: GNRFET and CNTFET comparison

    NASA Astrophysics Data System (ADS)

    Frégonèse, Sébastien; Maneux, Cristell; Zimmer, Thomas

    2010-11-01

    This paper presents a versatile compact model dedicated to 1D transistors in order to predict the ultimate performances of nano-device-based circuits. We have developed a thermionic charge model based on the non-parabolic-energy-dispersion-relation NPEDR. The model is valid for both CNTFET and GNRFET. Model results are compared with GNRFET NEGF simulations. Then, GNRFET and CNTFET performances are analysed through two circuit demonstrators such as a ring oscillator circuit and 6T RAM.

  13. Line shape of the non-thermal 6300 A O/1D/ emission

    NASA Technical Reports Server (NTRS)

    Schmitt, G. A.; Abreu, V. J.; Hays, P. B.

    1982-01-01

    The two-population model of Schmitt, Abreu and Hays (1981) is used to calculate the line shape of the atomic oxygen metastable state, nonthermal O(1D) 6300 A emission, in order to simulate observations made from a space platform at different zenith angles and altitudes. The Addition theorem, for spherical harmonics of a Legendre polynomial expansion of the nonthermal population distribution function, is used to obtain nonthermal line shapes observed at zenith angles other than the local vertical one.

  14. Quasi-1D van der Waals materials as high current-density local interconnects (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Stolyarov, Maxim; Aytan, Ece; Bloodgood, Matthew; Salguero, Tina T.; Balandin, Alexander A.

    2016-09-01

    The continuous downscaling of interconnect dimensions in combination with the introduction of low-k dielectrics has increased the number of heat dissipation, integration and reliability challenges in modern electronics. As a result, there is a strong need for new materials that have high current-carrying capacity for applications as nanoscale interconnects. In this presentation, we show that quasi-one-dimensional (1D) van der Waals metals such as TaSe3 have excellent breakdown current density exceeding that of 5 MA/cm2. This value is above that currently achievable in conventional copper or aluminum wires. The quasi-1D van der Waals materials are characterized by strong bonds along one dimension and weak van der Waals bonds along two other dimensions. The material for this study was grown by the chemical vapor transport (CVT) method. Both mechanical and chemical exfoliation methods were used to fabricate nanowires with lateral dimensions below 100 nm. The dimensions of the quasi-1D nanowires were verified with scanning electron microscopy (SEM) and atomic force microscopy (AFM). The metal (Ti/Au) contacts for the electrical characterization were deposited using electron beam evaporation (EBE). The measurements were conducted on a number of prototype interconnects with multiple electric contacts to ensure reproducibility. The obtained results suggest that quasi-1D van der Waals metals present a feasible alternative to conventional copper interconnects in terms of the current-carrying capacity and the breakdown current-density. This work was supported, in part, by the SRC and DARPA through STARnet Center for Function Accelerated nanoMaterial Engineering (FAME).

  15. A marching in space and time (MAST) solver of the shallow water equations. Part I: The 1D model

    NASA Astrophysics Data System (ADS)

    Aricò, C.; Tucciarelli, T.

    2007-05-01

    A new approach is presented for the numerical solution of the complete 1D Saint-Venant equations. At each time step, the governing system of partial differential equations (PDEs) is split, using a fractional time step methodology, into a convective prediction system and a diffusive correction system. Convective prediction system is further split into a convective prediction and a convective correction system, according to a specified approximated potential. If a scalar exact potential of the flow field exists, correction vanishes and the solution of the convective correction system is the same solution of the prediction system. Both convective prediction and correction systems are shown to have at each x - t point a single characteristic line, and a corresponding eigenvalue equal to the local velocity. A marching in space and time (MAST) technique is used for the solution of the two systems. MAST solves a system of two ordinary differential equations (ODEs) in each computational cell, using for the time discretization a self-adjusting fraction of the original time step. The computational cells are ordered and solved according to the decreasing value of the potential in the convective prediction step and to the increasing value of the same potential in the convective correction step. The diffusive correction system is solved using an implicit scheme, that leads to the solution of a large linear system, with the same order of the cell number, but sparse, symmetric and well conditioned. The numerical model shows unconditional stability with regard of the Courant-Friedrichs-Levi (CFL) number, requires no special treatment of the source terms and a computational effort almost proportional to the cell number. Several tests have been carried out and results of the proposed scheme are in good agreement with analytical solutions, as well as with experimental data.

  16. Comet 73P/Schwassmann-Wachmann 3: O(1D) and H2O Production Rates

    NASA Astrophysics Data System (ADS)

    Hall, Tanya L.; Mierkiewicz, E. J.; Haffner, L. M.; Roesler, F. L.; Harris, W. M.

    2006-12-01

    In May 2006, comet 73P/Schwassmann-Wachmann 3 (SW3) made the closest approach (0.075 AU) to the Earth of a short period comet in more than 75 years. During the comet's 1995/1996 apparition it split into several fragments and, as of March 2006, SW3 was in eight major pieces. From May 1, 2006 through May 6, 2006 we performed a series of [OI] and NH2 (near 6300 Å) observations of the two brightest fragments, SW3-B and SW3-C, using the dual-etalon Fabry-Perot spectrometer that comprises the Wisconsin H-alpha Mapper (WHAM). At the time of our observations the Doppler shift of the comet was within a few km/s of the spectral resolving limit of WHAM (12 km/s), and great care was needed to isolate the blended cometary [OI] emission from the bright terrestrial [OI] emission line. In this poster we will discuss our analysis procedure and our preliminary total O(1D) production rates. Given the photodissociation of H2O and OH as sources of O(1D), we will also present an estimate of the H2O production rates for fragments SW3-B and SW3-C based on our WHAM O(1D) observations. This work was supported by the National Science Foundation's REU program and the Department of Defense's ASSURE program through NSF Award AST-0453442

  17. Characterisation of J(O1D) at Cape Grim 2000-2005

    NASA Astrophysics Data System (ADS)

    Wilson, S. R.

    2015-07-01

    Estimates of the rate of production of excited oxygen atoms due to the photolysis of ozone (J(O1D)) have been derived from radiation measurements carried out at Cape Grim, Tasmania (40.6° S, 144.7° E). The individual measurements have a total uncertainty of 16 % (1σ). These estimates agree well with model estimates of clear-sky photolysis rates. Observations spanning 2000-2005 have been used to quantify the impact of season, clouds and ozone column amount. The annual cycle of J(O1D) has been investigated via monthly means. These means show an interannual variation (monthly standard deviation) of 9 %, but in midsummer and midwinter this reduces to 3-5 %. Variations in solar zenith angle and total column ozone explain 86 % of the observed variability in the measured photolysis rates. The impact of total column ozone, expressed as a radiation amplification factor (RAF), is found to be ~ 1.53, in agreement with model estimates. This ozone dependence explains 20 % of the variation observed at medium solar zenith angles (30-50°). The impact of clouds results in a median reduction of 30 % in J(O1D) for the same solar zenith angle range. Including estimates of cloudiness derived from long-wave radiation measurements resulted in a statistically significant fit to observations, but the quality of the fit did not increase significantly as measured by the adjusted R2.

  18. 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.

  19. Avidity-Dependent Programming of Autoreactive T Cells in T1D

    PubMed Central

    Durinovic-Belló, Ivana; Gersuk, Vivian H.; Ni, Chester; Wu, Rebecca; Thorpe, Jerill; Jospe, Nicholas; Sanda, Srinath; Greenbaum, Carla J.; Nepom, Gerald T.

    2014-01-01

    Fate determination for autoreactive T cells relies on a series of avidity-dependent interactions during T cell selection, represented by two general types of signals, one based on antigen expression and density during T cell development, and one based on genes that interpret the avidity of TCR interaction to guide developmental outcome. We used proinsulin-specific HLA class II tetramers to purify and determine transcriptional signatures for autoreactive T cells under differential selection in type 1 diabetes (T1D), in which insulin (INS) genotypes consist of protective and susceptible alleles that regulate the level of proinsulin expression in the thymus. Upregulation of steroid nuclear receptor family 4A (NR4A) and early growth response family genes in proinsulin-specific T cells was observed in individuals with susceptible INS-VNTR genotypes, suggesting a mechanism for avidity-dependent fate determination of the T cell repertoire in T1D. The NR4A genes act as translators of TCR signal strength that guide central and peripheral T cell fate decisions through transcriptional modification. We propose that maintenance of an NR4A-guided program in low avidity autoreactive T cells in T1D reflects their prior developmental experience influenced by proinsulin expression, identifying a pathway permissive for autoimmunity. PMID:24844227

  20. Interview: glycolipid antigen presentation by CD1d and the therapeutic potential of NKT cell activation.

    PubMed

    Kronenberg, Mitchell

    2007-01-01

    Natural Killer T cells (NKT) are critical determinants of the immune response to cancer, regulation of autioimmune disease, clearance of infectious agents, and the development of artheriosclerotic plaques. In this interview, Mitch Kronenberg discusses his laboratory's efforts to understand the mechanism through which NKT cells are activated by glycolipid antigens. Central to these studies is CD1d--the antigen presenting molecule that presents glycolipids to NKT cells. The advent of CD1d tetramer technology, a technique developed by the Kronenberg lab, is critical for the sorting and identification of subsets of specific glycolipid-reactive T cells. Mitch explains how glycolipid agonists are being used as therapeutic agents to activate NKT cells in cancer patients and how CD1d tetramers can be used to assess the state of the NKT cell population in vivo following glycolipid agonist therapy. Current status of ongoing clinical trials using these agonists are discussed as well as Mitch's prediction for areas in the field of immunology that will have emerging importance in the near future.

  1. Cutting edge: nonglycosidic CD1d lipid ligands activate human and murine invariant NKT cells.

    PubMed

    Silk, Jonathan D; Salio, Mariolina; Reddy, B Gopal; Shepherd, Dawn; Gileadi, Uzi; Brown, James; Masri, S Hajar; Polzella, Paolo; Ritter, Gerd; Besra, Gurdyal S; Jones, E Yvonne; Schmidt, Richard R; Cerundolo, Vincenzo

    2008-05-15

    Invariant NKT cells (iNKT cells) recognize CD1d/glycolipid complexes. We demonstrate that the nonglycosidic compound threitolceramide efficiently activates iNKT cells, resulting in dendritic cell (DC) maturation and the priming of Ag-specific T and B cells. Threitolceramide-pulsed DCs are more resistant to iNKT cell-dependent lysis than alpha-galactosylceramide-pulsed DCs due to the weaker affinity of the human iNKT TCR for CD1d/ threitolceramide than CD1d/alpha-galactosylceramide complexes. iNKT cells stimulated with threitolceramide also recover more quickly from activation-induced anergy. Kinetic and functional experiments showed that shortening or lengthening the threitol moiety by one hydroxymethylene group modulates ligand recognition, as human and murine iNKT cells recognize glycerolceramide and arabinitolceramide differentially. Our data broaden the range of potential iNKT cell agonists. The ability of these compounds to assist the priming of Ag-specific immune responses while minimizing iNKT cell-dependent DC lysis makes them attractive adjuvants for vaccination strategies.

  2. 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.

  3. Self-assembly of functional molecules into 1D crystalline nanostructures.

    PubMed

    Guo, Yanbing; Xu, Liang; Liu, Huibiao; Li, Yongjun; Che, Chi-Ming; Li, Yuliang

    2015-02-01

    Self-assembled functional nanoarchitectures are employed as important nanoscale building blocks for advanced materials and smart miniature devices to fulfill the increasing needs of high materials usage efficiency, low energy consumption, and high-performance devices. One-dimensional (1D) crystalline nanostructures, especially molecule-composed crystalline nanostructures, attract significant attention due to their fascinating infusion structure and functionality which enables the easy tailoring of organic molecules with excellent carrier mobility and crystal stability. In this review, we discuss the recent progress of 1D crystalline self-assembled nanostructures of functional molecules, which include both a small molecule-derived and a polymer-based crystalline nanostructure. The basic principles of the molecular structure design and the process engineering of 1D crystalline nanostructures are also discussed. The molecular building blocks, self-assembly structures, and their applications in optical, electrical, and photoelectrical devices are overviewed and we give a brief outlook on crucial issues that need to be addressed in future research endeavors.

  4. Subplane-based Control Rod Decusping Techniques for the 2D/1D Method in MPACT

    SciTech Connect

    Graham, Aaron M; Collins, Benjamin S; Downar, Thomas

    2017-01-01

    The MPACT transport code is being jointly developed by Oak Ridge National Laboratory and the University of Michigan to serve as the primary neutron transport code for the Virtual Environment for Reactor Applications Core Simulator. MPACT uses the 2D/1D method to solve the transport equation by decomposing the reactor model into a stack of 2D planes. A fine mesh flux distribution is calculated in each 2D plane using the Method of Characteristics (MOC), then the planes are coupled axially through a 1D NEM-P$_3$ calculation. This iterative calculation is then accelerated using the Coarse Mesh Finite Difference method. One problem that arises frequently when using the 2D/1D method is that of control rod cusping. This occurs when the tip of a control rod falls between the boundaries of an MOC plane, requiring that the rodded and unrodded regions be axially homogenized for the 2D MOC calculations. Performing a volume homogenization does not properly preserve the reaction rates, causing an error known as cusping. The most straightforward way of resolving this problem is by refining the axial mesh, but this can significantly increase the computational expense of the calculation. The other way of resolving the partially inserted rod is through the use of a decusping method. This paper presents new decusping methods implemented in MPACT that can dynamically correct the rod cusping behavior for a variety of problems.

  5. 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.

  6. A Systematic Comparison between 1-D and 3-D Hemodynamics in Compliant Arterial Models

    PubMed Central

    Xiao, Nan; Alastruey, Jordi; Figueroa, C. Alberto

    2015-01-01

    SUMMARY In this article, we present a systematic comparison of computational hemodynamics in arterial models with deformable vessel walls using a one-dimensional (1-D) and a three-dimensional (3-D) method. The simulations were performed using a series of idealized compliant arterial models representing the common carotid artery, thoracic aorta, aortic bifurcation, and full aorta from the arch to the iliac bifurcation. The formulations share identical outflow boundary conditions and have compatible material laws. We also present an iterative algorithm to select the parameters for the outflow boundary conditions using the 1-D theory to achieve a desired systolic and diastolic pressure at a particular vessel. This 1-D/3-D framework can be used to efficiently determine material and boundary condition parameters for 3-D subject-specific arterial models with deformable vessel walls. Finally, we explore the impact of different anatomical features and hemodynamic conditions on the numerical predictions. The results show good agreement between the two schemes, especially during the diastolic phase of the cycle. PMID:24115509

  7. 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.

  8. Tunable evolutions of wave modes and bandgaps in quasi-1D cylindrical phononic crystals

    NASA Astrophysics Data System (ADS)

    Meidani, Mehrashk; Kim, Eunho; Li, Feng; Yang, Jinkyu; Ngo, Duc

    2015-01-01

    We investigate the tunable characteristics of mechanical waves propagating in quasi-1D phononic crystals composed of horizontally stacked short cylinders at various contact angles and offsets. According to the Hertzian contact theory, elastic compression of laterally-touching cylindrical bodies exhibits a various range of contact stiffness depending on their alignment angles. In this study, we first assemble cylindrical particles in various combinations of inclination angles and systematically examine their forming mechanisms of frequency bandgaps. We also investigate the effect of the rattling motions of cylindrical particles by introducing asymmetric center-of-mass offsets with respect to their contact points. We find that the frequency responses of these quasi-1D phononic crystals evolve into multiple band structures as we employ higher deviations of contact angles and offsets. We calculate the dispersive behavior of propagating waves using a discrete particle model for simple zero-offset cases, while we use a finite element method for simulating the rattling motions of particles under non-zero offsets. We report branching behavior of frequency band structures and the evolution of their vibration modes as we manipulate the contact angles and offsets of the phononic crystals. This study implies that we can leverage the versatile wave filtering characteristics of quasi-1D phononic crystals to construct tunable wave filtering devices for engineering applications.

  9. 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.

  10. 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

  11. 1D Cole-Cole inversion of TEM transients influenced by induced polarization

    NASA Astrophysics Data System (ADS)

    Seidel, Marc; Tezkan, Bülent

    2017-03-01

    Effects of induced polarization (IP) can have an impact on time-domain electromagnetic measurements (TEM) and may lead to sign reversals in the recorded transients. To study these IP effects on TEM data, a new 1D inversion algorithm was developed for both, the central-loop and the separate-loop TEM configurations using the Cole-Cole relaxation model. 1D forward calculations for a homogeneous half-space were conducted with the aim of analyzing the impacts of the Cole-Cole parameters on TEM transients with respect to possible sign reversals. The forward modelings showed that the variation of different parameters have comparable effects on the TEM transients. This leads to an increasing number of equivalent models as a result of inversion calculations. Subsequently, 1D inversions of synthetic data were performed to study the potentials and limitations of the algorithm regarding the resolution of the Cole-Cole parameters. In order to achieve optimal inversion results, it was essential to error-weight the data points in the direct vicinity of sign reversals. The obtained findings were eventually adopted on the inversion of real field data which contained considerable IP signatures such as sign reversals. One field data set was recorded at the Nakyn kimberlite field in Western Yakutiya, Russia, in the central-loop configuration. Another field data set originates from a waste site in Cologne, Germany, and was measured utilizing the separate-loop configuration.

  12. Generation of ELF and ULF electromagnetic waves by modulated heating of the ionospheric F2 region

    NASA Astrophysics Data System (ADS)

    Eliasson, B.; Chang, C.-L.; Papadopoulos, K.

    2012-10-01

    We present a theoretical and numerical study of the generation of extremely low frequency (ELF) and ultra-low frequency (ULF) waves by the modulation of the electron pressure at the F2-region with an intense high-frequency electromagnetic wave. The study is based on a cold plasma Hall-MHD model, including electron-neutral and ion-neutral collisions, which governs the dynamics of magnetostatic waves and their propagation through the ionospheric layers. Magnetosonic waves generated in the F2 region are propagating isotropically and are channeled in the ionospheric waveguide, while shear Alfvén waves are propagating along the magnetic field. To penetrate the ionosphere from the F2 peak at 300 km to the ground, the magnetostatic waves first propagate as magnetosonic or shear Alfvén waves that encounter a diffusive layer from about 150 km to 120 km where the Pedersen conductivity dominates, and then as helicon (whistler-like) mode waves from about 120 km to 80 km where the ions are collisionally glued to the neutrals and the Hall conductivity dominates. By performing numerical simulations and studying the dispersive properties of the wave modes, we investigate the dynamics and penetration of ELF/ULF waves through the ionospheric layers to the ground and along the geomagnetic field lines to the magnetosphere. Realistic profiles of the ionospheric profiles of conductivity and density are used, together with different configurations of the geomagnetic field, relevant for both the high, mid and equatorial latitudes. Some of the results are compared with recent HAARP experiments.

  13. IL2RA/CD25 Gene Polymorphisms: Uneven Association with Multiple Sclerosis (MS) and Type 1 Diabetes (T1D)

    PubMed Central

    Alcina, Antonio; Fedetz, María; Ndagire, Dorothy; Fernández, Oscar; Leyva, Laura; Guerrero, Miguel; Abad-Grau, María M.; Arnal, Carmen; Delgado, Concepción; Lucas, Miguel; Izquierdo, Guillermo; Matesanz, Fuencisla

    2009-01-01

    Background IL-2 receptor (IL2R) alpha is the specific component of the high affinity IL2R system involved in the immune response and in the control of autoimmunity. Methods and Results Here we perform a replication and fine mapping of the IL2RA gene region analyzing 3 SNPs previously associated with multiple sclerosis (MS) and 5 SNPs associated with type 1 diabetes (T1D) in a collection of 798 MS patients and 927 matched Caucasian controls from the south of Spain. We observed association with MS in 6 of 8 SNPs. The rs1570538, at the 3′- UTR extreme of the gene, previously reported to have a weak association with MS, is replicated here (P = 0.032). The most associated T1D SNP (rs41295061) was not associated with MS in the present study. However, the rs35285258, belonging to another independent group of SNPs associated with T1D, showed the maximal association in this study but different risk allele. We replicated the association of only one (rs2104286) of the two IL2RA SNPs identified in the recently performed genome-wide association study of MS. Conclusions These findings confirm and extend the association of this gene with MS and reveal a genetic heterogeneity of the associated polymorphisms and risk alleles between MS and T1D suggesting different immunopathological roles of IL2RA in these two diseases. PMID:19125193

  14. An energy- and charge-conserving, nonlinearly implicit, electromagnetic 1D-3V Vlasov-Darwin particle-in-cell algorithm

    NASA Astrophysics Data System (ADS)

    Chen, G.; Chacón, L.

    2014-10-01

    A recent proof-of-principle study proposes a nonlinear electrostatic implicit particle-in-cell (PIC) algorithm in one dimension (Chen et al., 2011). The algorithm employs a kinetically enslaved Jacobian-free Newton-Krylov (JFNK) method, and conserves energy and charge to numerical round-off. In this study, we generalize the method to electromagnetic simulations in 1D using the Darwin approximation to Maxwell's equations, which avoids radiative noise issues by ordering out the light wave. An implicit, orbit-averaged, time-space-centered finite difference scheme is employed in both the 1D Darwin field equations (in potential form) and the 1D-3V particle orbit equations to produce a discrete system that remains exactly charge- and energy-conserving. Furthermore, enabled by the implicit Darwin equations, exact conservation of the canonical momentum per particle in any ignorable direction is enforced via a suitable scattering rule for the magnetic field. We have developed a simple preconditioner that targets electrostatic waves and skin currents, and allows us to employ time steps O(√{mi /me } c /veT) larger than the explicit CFL. Several 1D numerical experiments demonstrate the accuracy, performance, and conservation properties of the algorithm. In particular, the scheme is shown to be second-order accurate, and CPU speedups of more than three orders of magnitude vs. an explicit Vlasov-Maxwell solver are demonstrated in the "cold" plasma regime (where kλD ≪ 1).

  15. Can oriented-attachment be an efficient growth mechanism for the synthesis of 1D nanocrystals via atomic layer deposition?

    NASA Astrophysics Data System (ADS)

    Wen, Kechun; He, Weidong

    2015-09-01

    One-dimensional (1D) nanocrystals, such as nanorods and nanowires, have received extensive attention in the nanomaterials field due to their large surface areas and 1D confined transport properties. Oriented attachment (OA) is now recognized as a major growth mechanism for efficiently synthesizing 1D nanocrystals. Recently, atomic layer deposition (ALD) has been modified to be a powerful vapor-phase technique with which to synthesize 1D OA nanorods/nanowires with high efficiency and quality by increasing the temperature and purging time. In this invited mini-review, we look into the advantages of OA and high-temperature ALD, and investigate the potential of employing the OA growth mechanism for the synthesis of 1D nanocrystals via modified ALD, aiming to provide guidance to researchers in the fields of both OA and ALD for efficient synthesis of 1D nanocrystals.

  16. A technique for individual atom delivery into a crossed vortex bottle beam trap using a dynamic 1D optical lattice

    NASA Astrophysics Data System (ADS)

    Dinardo, Brad A.; Anderson, Dana Z.

    2016-12-01

    We describe a system for loading a single atom from a reservoir into a blue-detuned crossed vortex bottle beam trap using a dynamic 1D optical lattice. The lattice beams are frequency chirped using acousto-optic modulators, which causes the lattice to move along its axial direction and behave like an optical conveyor belt. A stationary lattice is initially loaded with approximately 6000 atoms from a reservoir, and the conveyor belt transports them 1.1 mm from the reservoir to a bottle beam trap, where a single atom is loaded via light-assisted collisions. Photon counting data confirm that an atom can be delivered and loaded into the bottle beam trap 13.1% of the time.

  17. Controlled Self-Assembly of Cyclophane Amphiphiles: From 1D Nanofibers to Ultrathin 2D Topological Structures

    SciTech Connect

    Cai, Zhengxu; Li, Lianwei; Lo, Wai-Yip; Zhao, Donglin; Wu, Qinghe; Zhang, Na; Su, Yu-An; Chen, Wei; Yu, Luping

    2016-07-05

    A novel series of amphiphilic TC-PEG molecules were designed and synthesized based on the orthogonal cyclophane unit. These molecules were able to self-assemble from 1D nanofibers and nanobelts to 2D ultrathin nanosheets (3 nm thick) in a controlled way by tuning the length of PEG side chains. The special structure of the cyclophane moiety allowed control in construction of nanostructures through programmed noncovalent interactions (hydrophobic hydrophilic interaction and pi-pi interaction). The self-assembled nanostructures were characterized by combining real space imaging (TEM, SEM, and AFM) and reciprocal space scattering (GIWAXS) techniques. This unique supramolecular system may provide a new strategy for the design of materials with tunable nanomorphology and functionality.

  18. Force on a slow moving impurity due to thermal and quantum fluctuations in a 1D Bose-Einstein condensate

    SciTech Connect

    Roberts, David; Sykes, Andrew

    2009-01-01

    We study the drag force acting on an impurity moving through a 1D Bose-Einstein condensate in the presence of both quantum and thermal fluctuations. We are able to find exact analytical solutions of the partial differential equations to the level of the Bogoliubov approximation. At zero temperature, we find a nonzero force is exerted on the impurity at subcritical velocities, due to the scattering of quantum fluctuations. We make the following explicit assumptions: far from the impurity the system is in a quantum state given by that of a zero (or finite) temperature Bose-Einstein condensate, and the scattering process generates only causally related reflection/transmission. The results raise unanswered questions in the quantum dynamics associated with the formation of persistent currents.

  19. 3-D imaging of large scale buried structure by 1-D inversion of very early time electromagnetic (VETEM) data

    USGS Publications Warehouse

    Aydmer, A.A.; Chew, W.C.; Cui, T.J.; Wright, D.L.; Smith, D.V.; Abraham, J.D.

    2001-01-01

    A simple and efficient method for large scale three-dimensional (3-D) subsurface imaging of inhomogeneous background is presented. One-dimensional (1-D) multifrequency distorted Born iterative method (DBIM) is employed in the inversion. Simulation results utilizing synthetic scattering data are given. Calibration of the very early time electromagnetic (VETEM) experimental waveforms is detailed along with major problems encountered in practice and their solutions. This discussion is followed by the results of a large scale application of the method to the experimental data provided by the VETEM system of the U.S. Geological Survey. The method is shown to have a computational complexity that is promising for on-site inversion.

  20. The impact of lone pair-π interactions on photochromic properties in 1-D naphthalene diimide coordination networks.

    PubMed

    Liu, Jian-Jun; Guan, Ying-Fang; Chen, Yong; Lin, Mei-Jin; Huang, Chang-Cang; Dai, Wen-Xin

    2015-10-21

    Lone pair-π interaction is an important but less studied binding force. Generally, it is too weak to influence the physical properties of supramolecular systems. Herein we reported the first example exhibiting the impact of lone pair-π interactions on photochromic properties of naphthalene diimide based coordination networks. In three isostructural 1-D networks, [(DPNDI)ZnX2] (DPNDI = N,N-di(4-pyridyl)-1,4,5,8-naphthalene diimide, X = Cl for 1, X = Br for 2 and X = I for 3), they exhibit different electron-transfer photochromic behaviors due to different lone pair-π interactions between the capped halogen atoms and electron-deficient DPNDI moieties. Specifically, 1 and 2 but not 3 are photochromic, which is attributed to a stronger lone pair-π interaction in 3 than those in 1 and 2. This study anticipates breaking a new path for designing novel photochromic materials through such unnoticeable supramolecular interactions.

  1. Design of plasmonic near-field transducers in heat-assisted magnetic recording: 1D Fourier approach

    NASA Astrophysics Data System (ADS)

    Gan, C. H.; Fernandez-Garcia, R.; Hardy, M. J.; Neira, A.; Bance, S.; Gubbins, M. A.

    2016-09-01

    Heat-assisted magnetic recording (HAMR) is a potential enabling technology for ultrahigh density data storage systems. In HAMR, a near-field transducer (NFT) delivers a subdiffraction heat spot to record bits of data on a high-anisotropy magnetic media. We developed an intuitive 1D Fourier model that expedites the analysis and design of the NFT. Among other strengths, the simple model predicts rather surprisingly and in agreement with 3D simulations, that for metallic nanoresonators the longitudinal component of the electric field dominates the heat transfer to the media. The proposed Fourier model serves well as a platform to study electromagnetic behavior such as field confinement and heat spot generation of 3D NFT designs.

  2. 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

  3. 1D and 2D urban dam-break flood modelling in Istanbul, Turkey

    NASA Astrophysics Data System (ADS)

    Ozdemir, Hasan; Neal, Jeffrey; Bates, Paul; Döker, Fatih

    2014-05-01

    Urban flood events are increasing in frequency and severity as a consequence of several factors such as reduced infiltration capacities due to continued watershed development, increased construction in flood prone areas due to population growth, the possible amplification of rainfall intensity due to climate change, sea level rise which threatens coastal development, and poorly engineered flood control infrastructure (Gallegos et al., 2009). These factors will contribute to increased urban flood risk in the future, and as a result improved modelling of urban flooding according to different causative factor has been identified as a research priority (Gallegos et al., 2009; Ozdemir et al. 2013). The flooding disaster caused by dam failures is always a threat against lives and properties especially in urban environments. Therefore, the prediction of dynamics of dam-break flows plays a vital role in the forecast and evaluation of flooding disasters, and is of long-standing interest for researchers. Flooding occurred on the Ayamama River (Istanbul-Turkey) due to high intensity rainfall and dam-breaching of Ata Pond in 9th September 2009. The settlements, industrial areas and transportation system on the floodplain of the Ayamama River were inundated. Therefore, 32 people were dead and millions of Euros economic loses were occurred. The aim of this study is 1 and 2-Dimensional flood modelling of the Ata Pond breaching using HEC-RAS and LISFLOOD-Roe models and comparison of the model results using the real flood extent. The HEC-RAS model solves the full 1-D Saint Venant equations for unsteady open channel flow whereas LISFLOOD-Roe is the 2-D shallow water model which calculates the flow according to the complete Saint Venant formulation (Villanueva and Wright, 2006; Neal et al., 2011). The model consists a shock capturing Godunov-type scheme based on the Roe Riemann solver (Roe, 1981). 3 m high resolution Digital Surface Model (DSM), natural characteristics of the pond

  4. Abnormal clock gene expression and locomotor activity rhythms in two month-old female APPSwe/PS1dE9 mice.

    PubMed

    Oyegbami, Olaide; Collins, Hilary M; Pardon, Marie C; Ebling, Fran Jp; Heery, David M; Moran, Paula M

    2017-03-17

    In addition to cognitive decline, Alzheimer's disease (AD) is also characterized by agitation and disruptions in activity and sleep. These symptoms typically occur in the evening or at night and have been referred to as 'sundowning'. These symptoms are especially difficult for carers and there are no specific drug treatments. There is increasing evidence that these symptoms reflect an underlying pathology of circadian rhythm generation and transmission. We investigated whether a transgenic mouse model relevant to AD (APPswe/PS1dE9) exhibits circadian alterations in locomotor activity and expression of clock genes involved in the regulation of the circadian cycle. Female mice at 2 months of age were investigated in their home cage. Results show that the APPswe/PS1dE9 transgene alters levels and patterns in circadian rhythm of locomotor activity. Expression of the clock genes Per1, Per2, Cry1 and Cry2 was found to increase at night compared to day in wild-type control mice in the medulla/pons. This effect was blunted for Cry1 and Cry2 gene expression in APPswe/PS1dE9. In summary, this study suggests altered circadian regulation of locomotor activity is abnormal in female APPswe/PS1dE9 mice and that this alteration has biomolecular analogies in a widely available model of AD. Furthermore, the early age at which these effects are manifest suggests that these circadian effects may precede plaque development. The APPswe/PS1dE9 mouse genetic model may have potential to serve as a tool in understanding the neuropathology of circadian abnormalities in AD and as a model system to test novel therapeutic agents for these symptoms.

  5. Toward an understanding of foreground emission in the BICEP2 region

    SciTech Connect

    Flauger, Raphael; Hill, J. Colin; Spergel, David N. E-mail: jch@astro.princeton.edu

    2014-08-01

    BICEP2 has reported the detection of a degree-scale B-mode polarization pattern in the Cosmic Microwave Background (CMB) and has interpreted the measurement as evidence for primordial gravitational waves. Motivated by the profound importance of the discovery of gravitational waves from the early Universe, we examine to what extent a combination of Galactic foregrounds and lensed E-modes could be responsible for the signal. We reanalyze the BICEP2 results and show that the 100 ×150 GHz and 150 ×150 GHz data are consistent with a cosmology with r=0.2 and negligible foregrounds, but also with a cosmology with r=0 and a significant dust polarization signal. We give independent estimates of the dust polarization signal in the BICEP2 region using a number of different approaches: (1) data-driven models based on Planck 353 GHz intensity, polarization fractions inferred from the same Planck data used by the BICEP2 team but corrected for CMB and CIB contributions, and polarization angles from starlight polarization data or the Planck sky model; (2) the same set of pre-Planck models used by the BICEP2 team but taking into account the higher polarization fractions observed in the CMB- and CIB-corrected map; (3) a measurement of neutral hydrogen gas column density N{sub HI} in the BICEP2 region combined with an extrapolation of a relation between HI column density and dust polarization derived by Planck; and (4) a dust polarization map based on digitized Planck data, which we only use as a final cross-check. While these approaches are consistent with each other, the expected amplitude of the dust polarization power spectrum remains uncertain by about a factor of three. The lower end of the prediction leaves room for a primordial contribution, but at the higher end the dust in combination with the standard CMB lensing signal could account for the BICEP2 observations, without requiring the existence of primordial gravitational waves. By measuring the cross-correlations between

  6. Molecular Identification of Dendrobium Species (Orchidaceae) Based on the DNA Barcode ITS2 Region and Its Application for Phylogenetic Study

    PubMed Central

    Feng, Shangguo; Jiang, Yan; Wang, Shang; Jiang, Mengying; Chen, Zhe; Ying, Qicai; Wang, Huizhong

    2015-01-01

    The over-collection and habitat destruction of natural Dendrobium populations for their commercial medicinal value has led to these plants being under severe threat of extinction. In addition, many Dendrobium plants are similarly shaped and easily confused during the absence of flowering stages. In the present study, we examined the application of the ITS2 region in barcoding and phylogenetic analyses of Dendrobium species (Orchidaceae). For barcoding, ITS2 regions of 43 samples in Dendrobium were amplified. In combination with sequences from GenBank, the sequences were aligned using Clustal W and genetic distances were computed using MEGA V5.1. The success rate of PCR amplification and sequencing was 100%. There was a significant divergence between the inter- and intra-specific genetic distances of ITS2 regions, while the presence of a barcoding gap was obvious. Based on the BLAST1, nearest distance and TaxonGAP methods, our results showed that the ITS2 regions could successfully identify the species of most Dendrobium samples examined; Second, we used ITS2 as a DNA marker to infer phylogenetic relationships of 64 Dendrobium species. The results showed that cluster analysis using the ITS2 region mainly supported the relationship between the species of Dendrobium established by traditional morphological methods and many previous molecular analyses. To sum up, the ITS2 region can not only be used as an efficient barcode to identify Dendrobium species, but also has the potential to contribute to the phylogenetic analysis of the genus Dendrobium. PMID:26378526

  7. Molecular Identification of Dendrobium Species (Orchidaceae) Based on the DNA Barcode ITS2 Region and Its Application for Phylogenetic Study.

    PubMed

    Feng, Shangguo; Jiang, Yan; Wang, Shang; Jiang, Mengying; Chen, Zhe; Ying, Qicai; Wang, Huizhong

    2015-09-11

    The over-collection and habitat destruction of natural Dendrobium populations for their commercial medicinal value has led to these plants being under severe threat of extinction. In addition, many Dendrobium plants are similarly shaped and easily confused during the absence of flowering stages. In the present study, we examined the application of the ITS2 region in barcoding and phylogenetic analyses of Dendrobium species (Orchidaceae). For barcoding, ITS2 regions of 43 samples in Dendrobium were amplified. In combination with sequences from GenBank, the sequences were aligned using Clustal W and genetic distances were computed using MEGA V5.1. The success rate of PCR amplification and sequencing was 100%. There was a significant divergence between the inter- and intra-specific genetic distances of ITS2 regions, while the presence of a barcoding gap was obvious. Based on the BLAST1, nearest distance and TaxonGAP methods, our results showed that the ITS2 regions could successfully identify the species of most Dendrobium samples examined; Second, we used ITS2 as a DNA marker to infer phylogenetic relationships of 64 Dendrobium species. The results showed that cluster analysis using the ITS2 region mainly supported the relationship between the species of Dendrobium established by traditional morphological methods and many previous molecular analyses. To sum up, the ITS2 region can not only be used as an efficient barcode to identify Dendrobium species, but also has the potential to contribute to the phylogenetic analysis of the genus Dendrobium.

  8. Muscle beta1D integrin reinforces the cytoskeleton-matrix link: modulation of integrin adhesive function by alternative splicing.

    PubMed

    Belkin, A M; Retta, S F; Pletjushkina, O Y; Balzac, F; Silengo, L; Fassler, R; Koteliansky, V E; Burridge, K; Tarone, G

    1997-12-15

    Expression of muscle-specific beta1D integrin with an alternatively spliced cytoplasmic domain in CHO and GD25, beta1 integrin-minus cells leads to their phenotypic conversion. beta1D-transfected nonmuscle cells display rounded morphology, lack of pseudopodial activity, retarded spreading, reduced migration, and significantly enhanced contractility compared with their beta1A-expressing counterparts. The transfected beta1D is targeted to focal adhesions and efficiently displaces the endogenous beta1A and alphavbeta3 integrins from the sites of cell-matrix contact. This displacement is observed on several types of extracellular matrix substrata and leads to elevated stability of focal adhesions in beta1D transfectants. Whereas a significant part of cellular beta1A integrin is extractable in digitonin, the majority of the transfected beta1D is digitonin-insoluble and is strongly associated with the detergent-insoluble cytoskeleton. Increased interaction of beta1D integrin with the actin cytoskeleton is consistent with and might be mediated by its enhanced binding to talin. In contrast, beta1A interacts more strongly with alpha-actinin, than beta1D. Inside-out driven activation of the beta1D ectodomain increases ligand binding and fibronectin matrix assembly by beta1D transfectants. Phenotypic effects of beta1D integrin expression in nonmuscle cells are due to its enhanced interactions with both cytoskeletal and extracellular ligands. They parallel the transitions that muscle cells undergo during differentiation. Modulation of beta1 integrin adhesive function by alternative splicing serves as a physiological mechanism reinforcing the cytoskeleton- matrix link in muscle cells. This reflects the major role for beta1D integrin in muscle, where extremely stable association is required for contraction.

  9. Muscle β1D Integrin Reinforces the Cytoskeleton–Matrix Link: Modulation of Integrin Adhesive Function by Alternative Splicing

    PubMed Central

    Belkin, Alexey M.; Retta, S. Francesco; Pletjushkina, Olga Y.; Balzac, Fiorella; Silengo, Lorenzo; Fassler, Reinhard; Koteliansky, Victor E.; Burridge, Keith; Tarone, Guido

    1997-01-01

    Expression of muscle-specific β1D integrin with an alternatively spliced cytoplasmic domain in CHO and GD25, β1 integrin-minus cells leads to their phenotypic conversion. β1D-transfected nonmuscle cells display rounded morphology, lack of pseudopodial activity, retarded spreading, reduced migration, and significantly enhanced contractility compared with their β1A-expressing counterparts. The transfected β1D is targeted to focal adhesions and efficiently displaces the endogenous β1A and αvβ3 integrins from the sites of cell–matrix contact. This displacement is observed on several types of extracellular matrix substrata and leads to elevated stability of focal adhesions in β1D transfectants. Whereas a significant part of cellular β1A integrin is extractable in digitonin, the majority of the transfected β1D is digitonin-insoluble and is strongly associated with the detergent-insoluble cytoskeleton. Increased interaction of β1D integrin with the actin cytoskeleton is consistent with and might be mediated by its enhanced binding to talin. In contrast, β1A interacts more strongly with α-actinin, than β1D. Inside-out driven activation of the β1D ectodomain increases ligand binding and fibronectin matrix assembly by β1D transfectants. Phenotypic effects of β1D integrin expression in nonmuscle cells are due to its enhanced interactions with both cytoskeletal and extracellular ligands. They parallel the transitions that muscle cells undergo during differentiation. Modulation of β1 integrin adhesive function by alternative splicing serves as a physiological mechanism reinforcing the cytoskeleton– matrix link in muscle cells. This reflects the major role for β1D integrin in muscle, where extremely stable association is required for contraction. PMID:9396762

  10. Real-time 1-D/2-D transient elastography on a standard ultrasound scanner using mechanically induced vibration.

    PubMed

    Azar, Reza Zahiri; Dickie, Kris; Pelissier, Laurent

    2012-10-01

    Transient elastography has been well established in the literature as a means of assessing the elasticity of soft tissue. In this technique, tissue elasticity is estimated from the study of the propagation of the transient shear waves induced by an external or internal source of vibration. Previous studies have focused mainly on custom single-element transducers and ultrafast scanners which are not available in a typical clinical setup. In this work, we report the design and implementation of a transient elastography system on a standard ultrasound scanner that enables quantitative assessment of tissue elasticity in real-time. Two new custom imaging modes are introduced that enable the system to image the axial component of the transient shear wave, in response to an externally induced vibration, in both 1-D and 2-D. Elasticity reconstruction algorithms that estimate the tissue elasticity from these transient waves are also presented. Simulation results are provided to show the advantages and limitations of the proposed system. The performance of the system is also validated experimentally using a commercial elasticity phantom.

  11. Identification of 5-hydroxytryptamine1D binding sites in sheep caudate nucleus membranes.

    PubMed

    Pauwels, P J; Palmier, C; Briley, M

    1993-08-03

    Radioligand binding measurements were performed in membranes of sheep caudate nucleus using [3H]5-hydroxytryptamine (5-HT). [3H]5-HT labeled a population of high affinity binding sites with a Kd of 1.9 +/- 0.1 nM and a Bmax of 19.8 +/- 2.2 fmol/mg tissue. Combined 5-HTID/E binding sites were the predominant 5-HT1 subtype, accounting for 78% of the total population of 5-HT1 binding sites. 5-Carboxamidotryptamine (5-CT) and sumatriptan yielded inhibition curves which best fitted a two-site model with high affinity values of 0.8 and 10.1 nM, and 1000 and 206 nM for their low affinity components. The proportion of the high affinity 5-CT and sumatriptan binding sites was 79 and 72%. The binding affinity profile of 5-HT1D binding sites [5-CT > 5-HT > d-LSD > 5-MeOT > sumatriptan > RU 24,969 > metergoline > tryptamine = rauwolscine = methylsergide > yohimbine = methiothepin > TFMPP = 8-OH-DPAT > 2-methyl-5-HT > mCPP = quipazine = CP 93,129 > ketanserin > (-)-propranolol = haloperidol = ipsapirone] compares well to that reported for 5-HT1D receptor sites in human caudate and cortex (correlation coefficient: 0.99 and 0.98). The present results indicate that sheep caudate nucleus is a valid tissue for studying interaction of compounds with 5-HT1D binding sites in the relative absence of 5-HT1E binding sites.

  12. Simvastatin treatment preserves synaptic plasticity in AβPPswe/PS1dE9 mice.

    PubMed

    Métais, Charles; Brennan, Kathryn; Mably, Alex J; Scott, Michael; Walsh, Dominic M; Herron, Caroline E

    2014-01-01

    Epidemiological evidence suggests that chronic treatment with simvastatin may protect against the development of Alzheimer's disease (AD), but as yet it is unclear how this effect is mediated. Extensive data also indicates that the amyloid β-protein (Aβ) plays a central role in the disease process, and it has been suggested that the protective effects of simvastatin may be mediated by reducing Aβ production or by counteracting the toxic effects of Aβ. Accordingly, using the AβPPswe/PS1dE9 mouse model of AD, we investigated the effects of simvastatin on long-term potentiation (LTP), amyloid biology, and two key kinases involved in Aβ-mediated toxicity. Since burgeoning data indicate that both fibrillar and non-fibrillar forms of Aβ play a prominent role in AD pathogenesis, we were careful to investigate the effects of simvastatin on three biochemically distinct pools of Aβ. In untreated AβPPswe/PS1dE9 mice, there was a dramatic and significant increase in the levels of water-soluble Aβ between 6 and 8 months, but this remained constant between 8 and 18 months. In contrast, the concentrations of detergent-soluble and formic acid (FA)-soluble Aβ species increased across all ages examined, thus demonstrating that while amyloid deposition continued, the levels of water-soluble Aβ remained relatively constant. LTP was normal at 6 months, but was significantly impaired at 8 and 18 months. Importantly, a diet supplemented with 0.04% simvastatin for one month (at 7 months) positively affected synaptic plasticity in AβPPswe/PS1dE9 mice and did not significantly alter levels of water-soluble, detergent-soluble, or FA-soluble Aβ, but did increase phosphorylation of both Akt and GSK-3, while tau and tau phosphorylation were unaltered. These results indicate that the protective effects of simvastatin may be mediated by maintaining signaling pathways that help to protect and rescue LTP.

  13. 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.

  14. Using 1D2D Hydrodynamic Modeling to Inform Restoration Planning in the Atchafalaya River Basin, Louisiana

    NASA Astrophysics Data System (ADS)

    Hayden-Lesmeister, A.; Remo, J. W.; Piazza, B.

    2015-12-01

    The Atchafalaya River (AR) in Louisiana is the principal distributary of the Mississippi River (MR), and its basin contains the largest contiguous area of baldcypress-water tupelo swamp forests in North America. After designation of the Atchafalaya River Basin (ARB) as a federal floodway following the destructive 1927 MR flood, it was extensively modified to accommodate a substantial portion of the MR flow (~25%) to mitigate flooding in southern Louisiana. These modifications and increased flows resulted in substantial incision along large portions of the AR, altering connectivity between the river and its associated waterbodies. As a result of incision, the hydroperiod has been substantially altered, which has contributed to a decline in ecological health of the ARB's baldcypress-water tupelo forests. While it is recognized that the altered hydroperiod has negatively affected natural baldcypress regeneration, it is unclear whether proposed projects designed to enhance flow connectivity will increase long-term survival of these forests. In this study, we have constructed a 1D2D hydrodynamic model using SOBEK 2.12 to realistically model key physical parameters such as residence times, inundation extent, water-surface elevations (WSELs), and flow velocities to increase our understanding of the ARB's altered hydroperiod and the consequences for baldcypress-water tupelo forests. While the model encompasses a majority of the ARB, our modeling effort is focused on the Flat Lake Water Management Unit located in the southern portion of the ARB, where it will also be used to evaluate flow connectivity enhancement projects within the management unit. We believe our 1D2D hybrid hydraulic modeling approach will provide the flexibility and accuracy needed to guide connectivity enhancement efforts in the ARB and may provide a model framework for guiding similar efforts along other highly-altered river systems.

  15. Advanced Fuel Cycle Initiative AFC-1D, AFC-1G, and AFC-1H End of FY-07 Irradiation Report

    SciTech Connect

    Debra J Utterbeck; Gray S Chang; Misit A Lillo

    2007-09-01

    The purpose of the U.S. Advanced Fuel Cycle Initiative (AFCI), now within the broader context of the Global Nuclear Energy Partnership (GNEP), is to develop and demonstrate the technologies needed to transmute the long-lived transuranic isotopes contained in spent nuclear fuel into shorter-lived fission products. Success in this undertaking could potentially dramatically decrease the volume of material requiring disposal with attendant reductions in long-term radio-toxicity and heat load of high-level waste sent to a geologic repository. One important component of the technology development is investigation of irradiation/transmutation effects on actinide-bearing metallic fuel forms containing plutonium, neptunium, americium (and possibly curium) isotopes. Goals of this initiative include addressing the limited irradiation performance data available on metallic fuels with high concentrations of Pu, Np and Am, as are envisioned for use as actinide transmutation fuels. The AFC-1 irradiation experiments of transmutation fuels are expected to provide irradiation performance data on non-fertile and low-fertile fuel forms specifically, irradiation growth and swelling, helium production, fission gas release, fission product and fuel constituent migration, fuel phase equilibria, and fuel-cladding chemical interaction. Contained in this report are the to-date physics evaluations performed on three of the AFC-1 experiments; AFC-1D, AFC-1G and AFC-1H. The AFC-1D irradiation experiment consists of metallic non-fertile fuel compositions with minor actinides for potential use in accelerator driven systems and AFC-1G and AFC-1H irradiation experiments are part of the fast neutron reactor fuel development effort. The metallic fuel experiments and nitride experiment are high burnup analogs to previously irradiated experiments and are to be irradiated to = 40 at.% burnup.

  16. Multiresolution image representation using combined 2-D and 1-D directional filter banks.

    PubMed

    Tanaka, Yuichi; Ikehara, Masaaki; Nguyen, Truong Q

    2009-02-01

    In this paper, effective multiresolution image representations using a combination of 2-D filter bank (FB) and directional wavelet transform (WT) are presented. The proposed methods yield simple implementation and low computation costs compared to previous 1-D and 2-D FB combinations or adaptive directional WT methods. Furthermore, they are nonredundant transforms and realize quad-tree like multiresolution representations. In applications on nonlinear approximation, image coding, and denoising, the proposed filter banks show visual quality improvements and have higher PSNR than the conventional separable WT or the contourlet.

  17. Controlled mode tuning in 1-D 'RIM' plasmonic crystal trench cavities probed with coupled optical emitters.

    PubMed

    Liu, Tsung-li; Russell, Kasey J; Cui, Shanying; Hu, Evelyn L

    2013-12-02

    We present a design of plasmonic cavities that consists of two sets of 1-D plasmonic crystal reflectors on a plasmonic trench waveguide. A 'reverse image mold' (RIM) technique was developed to pattern high-resolution silver trenches and to embed emitters at the cavity field maximum, and FDTD simulations were performed to analyze the frequency response of the fabricated devices. Distinct cavity modes were observed from the photoluminescence spectra of the organic dye embedded within these cavities. The cavity geometry facilitates tuning of the modes through a change in cavity dimensions. Both the design and the fabrication technique presented could be extended to making trench waveguide-based plasmonic devices and circuits.

  18. Transport of a Bose gas in 1D disordered lattices at the fluid-insulator transition.

    PubMed

    Tanzi, Luca; Lucioni, Eleonora; Chaudhuri, Saptarishi; Gori, Lorenzo; Kumar, Avinash; D'Errico, Chiara; Inguscio, Massimo; Modugno, Giovanni

    2013-09-13

    We investigate the momentum-dependent transport of 1D quasicondensates in quasiperiodic optical lattices. We observe a sharp crossover from a weakly dissipative regime to a strongly unstable one at a disorder-dependent critical momentum. In the limit of nondisordered lattices the observations suggest a contribution of quantum phase slips to the dissipation. We identify a set of critical disorder and interaction strengths for which such critical momentum vanishes, separating a fluid regime from an insulating one. We relate our observation to the predicted zero-temperature superfluid-Bose glass transition.

  19. Stark broadening of halogen atom lines from (1 D) n p levels

    NASA Astrophysics Data System (ADS)

    Djurović, S.; Konjević, N.; Dimitrijević, M. S.

    1990-12-01

    We report results of a study of the Stark broadening of halogen atom lines from (1 D) n p levels. Wall stabilized arc is used as a plasma source. Electron densities 2.2 3.2×1022 m-3 are determined from the width of H α line and electron temperature 9300 10000 K from plasma composition data. The agreement with the results of simple semiclassical calculations is within the limits of the estimated errors of both experiment and theory. An explanation for the large discrepancy between theory and experiment detected for three BrI lines is offered.

  20. 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

  1. Isotopic exchange between carbon dioxide and ozone via O(1D) in the stratosphere

    NASA Technical Reports Server (NTRS)

    Yung, Yuk L.; Demore, W. B.; Pinto, Joseph P.

    1991-01-01

    A novel mechanism for isotropic exchange between CO2 and O3 via O(1D) + CO2 - CO3(asterisk) followed by CO3(asterisk) - CO2 + O(3P). A one-dimensional model calculation shows that this mechanism can account for the enrichment in O-18 in the stratospheric CO2 observed by Gamo et al. (1989), using the heavy O3 profile observed by Mauersberger (1981). The implications of this mechanism for other stratospheric species and as a source of isotopically heavy CO2 in the troposphere are briefly discussed.

  2. 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.

  3. New optical scheme for parallel processing of 1D gray images

    NASA Astrophysics Data System (ADS)

    Huang, Guoliang; Jin, Guofan; Wu, Minxian; Yan, Yingbai

    1994-06-01

    Based on mathematical morphology and digital umbra shading and shadowing algorithm, a new scheme for realizing the fundamental morphological operation of one dimensional gray images is proposed. The mathematical formula for the parallel processing of 1D gray images is summarized; some important conclusions of morphological processing from binary images to gray images are obtained. The advantages of this scheme is simple in structure, high resolution in gray level, and good in parallelism. It can raise the speed of performing morphological processing of gray images greatly and obtain more accurate results.

  4. Simulation and optimization of 1-D periodic dielectric nanostructures for light-trapping.

    PubMed

    Wang, Peng; Menon, Rajesh

    2012-01-16

    Light-trapping is essential to improve the performance of thin-film solar cells. In this paper, we perform a parametric optimization of 1-D square and sinusoidal grating structures that act as nanophotonic scatterers to increase light absorption in ultra-thin (10nm) solar cells. Our optimization reveals that the short-circuit current density in a device of active-layer thickness 10nm can be improved by a factor of ~5 in the presence of the scattering structure. More complex geometries allow for increased degrees of design freedom and potentially high enhancement of light absorption.

  5. Synthesis, characterization, and application of 1-D cerium oxide nanomaterials: a review.

    PubMed

    Lin, Kuen-Song; Chowdhury, Sujan

    2010-09-13

    The present work provides a comprehensive overview of the recent progress of research work toward developing new one dimensional (1-D) ceria (CeO(2)) 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 CeO(2) nanomaterials.

  6. Maximizing 1D “like” implosion performance for inertial confinement fusion science

    SciTech Connect

    Kline, John L.

    2016-07-15

    While the march towards achieving indirectly driven inertial confinement fusion at the NIF has made great progress, the experiments show that multi-dimensional effects still dominate the implosion performance. Low mode implosion symmetry and hydrodynamic instabilities seed by capsule mounting features appear to be two key limiting factors for implosion performance. One reason these factors have a large impact on the performance of ICF implosions is the high convergence required to achieve high fusion gains. To tackle these problems, a predictable implosion platform is needed meaning experiments must trade-off high gain for performance. To this end, LANL has adopted three main approaches to develop a 1D implosion platform where 1D means high yield over 1D clean calculations. Taking advantage of the properties of beryllium capsules, a high adiabat, low convergence platform is being developed. The higher drive efficiency for beryllium enables larger case-to-capsule ratios to improve symmetry at the expense of drive. Smaller capsules with a high adiabat drive are expected to reduce the convergence and thus increase predictability. The second approach is liquid fuel layers using wetted foam targets. With liquid fuel layers, the initial mass in the hot spot can be controlled via the target fielding temperature which changes the liquid vapor pressure. Varying the initial hot spot mass via the vapor pressure controls the implosion convergence and minimizes the need to vaporize the dense fuel layer during the implosion to achieve ignition relevant hot spot densities. The last method is double shell targets. Unlike hot spot ignition, double shells ignite volumetrically. The inner shell houses the DT fuel and the convergence of this cavity is relatively small compared to hot spot ignition. Radiation trapping and the longer confinement times relax the conditions required to ignite the fuel. Key challenges for double shell targets are coupling the momentum of the outer shell to

  7. A Low Beta and Exact Kinetic Equilibrium for a 1D Nonlinear Force-Free field

    NASA Astrophysics Data System (ADS)

    Allanson, O.; Neukirch, T.; Wilson, F.; Troscheit, S.

    2015-12-01

    We present results regarding 1D nonlinear force-free Vlasov-Maxell (VM) equilibria, in particular for the force-free Harris sheet (FFHS). All the known equilibria of this type - including those for the FFHS - have plasma-beta values greater than one, due to the specific way in which they have been constructed. Using transformation techniques we construct VM equilibria for the FFHS that can have plasma-beta values smaller than one. Some properties of the newly found equilibrium distribution functions will be discussed. Possible applications would be studies of collisionless magnetic reconnection, kinetic instabilities and other phenomena in space and astrophysical plasma.

  8. 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.

  9. Q1D-Polarons in Rigid Boundary Cylindrical Wires: "Mixed-Coupling Approximation"

    NASA Astrophysics Data System (ADS)

    Senger, R. T.; Erçelebý, A.

    1998-02-01

    We consider the interaction of a confined electron with bulk polar-optical phonons in a cylindrical quantum well wire with infinite boundary potential. Expressions for the polaron self energy and mass are derived within a composite variational scheme consisting of a strong-coupling characterization imposed in the lateral directions and a weak-coupling LLP-counterpart structured along the length of the wire. The formulation is seen to be rather commendable and yields a sensible description of the Q1D-polaron in thin wires of weak or intermediate electron-phonon coupling strengths.

  10. 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.

  11. Combined Excitatory and Inhibitory Coupling in a 1-D Array of Belousov-Zhabotinsky Droplets

    DTIC Science & Technology

    2014-01-01

    of information if it does not display a currently valid OMB control number . 1. REPORT DATE 2014 2. REPORT TYPE 3. DATES COVERED 00-00-2014 to 00...00-2014 4. TITLE AND SUBTITLE Combined excitatory and inhibitory coupling in a 1-D array of Belousov-Zhabotinsky droplets 5a. CONTRACT NUMBER 5b...GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S

  12. SILVA: EDF two-phase 1D annular model of a CFB boiler furnace

    SciTech Connect

    Montat, D.; Fauquet, P.; Lafanechere, L.; Bursi, J.M.

    1997-12-31

    Aiming to improve its knowledge of CFB boilers, EDF has initiated a R and D program including: laboratory work on mock-ups, numerical modelling and on-site tests in CFB power plants. One of the objectives of this program is the development of a comprehensive steady-state 1D model of the solid circulation loop, named SILVA, for plant operation and design evaluation purposes. This paper describes its mathematical and physical modelling. Promising validation of the model on cold mock-up and industrial CFB is presented.

  13. Thermodynamic nature of vitrification in a 1D model of a structural glass former

    NASA Astrophysics Data System (ADS)

    Semenov, A. N.

    2015-07-01

    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.

  14. 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.

  15. Investigation of 1-D crustal velocity structure beneath Izmir Gulf and surroundings by using local earthquakes

    NASA Astrophysics Data System (ADS)

    Polat, Orhan; Özer, Ćaglar

    2016-04-01

    In this study; we examined one dimensional crustal velocity structure of Izmir gulf and surroundings. We used nearly one thousand high quality (A and B class) earthquake data which recorded by Disaster and Emergency Management Presidency (AFAD) [1], Bogazici University (BU-KOERI) [2] and National Observatory of Athens (NOA) [3,4]. We tried several synthetic tests to understand power of new velocity structure, and examined phase residuals, RMS values and shifting tests. After evaluating these tests; we decided one dimensional velocity structure and minimum 1-D P wave velocities, hypocentral parameter and earthquake locations from VELEST algorithm. Distribution of earthquakes was visibly improved by using new minimum velocity structure.

  16. Local circuitry involving parvalbumin-positive basket cells in the CA2 region of the hippocampus.

    PubMed

    Mercer, Audrey; Eastlake, Karen; Trigg, Hayley L; Thomson, Alex M

    2012-01-01

    There is a growing recognition that the CA2 region of the hippocampus has its own distinctive properties, inputs, and pathologies. The dendritic and axonal patterns of some interneurons in this region are also strikingly different from those described previously in CA1 and CA3. The local circuitry in this region, however, had yet to be studied in detail. Accordingly, using dual intracellular recordings and biocytin-filling, excitatory and inhibitory connections involving CA2 parvalbumin-positive basket cells were characterized for the first time. CA2 basket cells targeted neighboring pyramidal cells and received excitatory inputs from them. CA2 basket cells that resembled those in CA1 with a fast spiking behavior and dendritic tree confined to the region of origin received depressing excitatory postsynaptic potentials (EPSPs). In contrast, unlike CA1 basket cells but like CA1 Oriens-Lacunosum Moleculare (OLM) cells, the majority of CA2 basket cells had horizontally oriented dendrites in Stratum Oriens (SO), which extended into all three CA subfields, had an adapting firing pattern, presented a "sag" in their voltage responses to hyperpolarizing current injection, and received facilitating EPSPs. The expression of I(h) did not influence the EPSP time courses and paired pulse ratios (PPR). Estimates of the probability of release (p) for the depressing and facilitating EPSPs were correlated with the PPR. Connections with low probabilities of release had higher PPR. Quantal amplitude (q) for the facilitating connections was larger than q at depressing inputs onto fast spiking basket cells.

  17. New pyrazolyl and thienyl aminohydantoins as potent BACE1 inhibitors: exploring the S2' region.

    PubMed

    Malamas, Michael S; Erdei, Jim; Gunawan, Iwan; Barnes, Keith; Hui, Yu; Johnson, Matthew; Robichaud, Albert; Zhou, Ping; Yan, Yinfa; Solvibile, William; Turner, Jim; Fan, Kristi Yi; Chopra, Rajiv; Bard, Jonathan; Pangalos, Menelas N

    2011-09-15

    The proteolytic enzyme β-secretase (BACE1) plays a central role in the synthesis of the pathogenic β-amyloid in Alzheimer's disease. SAR studies of the S2' region of the BACE1 ligand binding pocket with pyrazolyl and thienyl P2' side chains are reported. These analogs exhibit low nanomolar potency for BACE1, and demonstrate >50- to 100-fold selectivity for the structurally related aspartyl proteases BACE2 and cathepsin D. Small groups attached at the nitrogen of the P2' pyrazolyl moiety, together with the P3 pyrimidine nucleus projecting into the S3 region of the binding pocket, are critical components to ligand's potency and selectivity. P2' thiophene side chain analogs are highly potent BACE1 inhibitors with excellent selectivity against cathepsin D, but only modest selectivity against BACE2. The cell-based activity of these new analogs tracked well with their increased molecular binding with EC(50) values of 0.07-0.2 μM in the ELISA assay for the most potent analogs.

  18. In-Situ F2-Region Plasma Density and Temperature Measurements from the International Space Station

    NASA Technical Reports Server (NTRS)

    Coffey, Victoria; Wright, Kenneth; Minow, Joseph

    2008-01-01

    The International Space Station orbit provides an ideal platform for in-situ studies of space weather effects on the mid and low latitude F-2 region ionosphere. The Floating Potential Measurement Unit (FPMU) operating on the ISS since Aug 2006. is a suite of plasma instruments: a Floating Potential Probe (FPP), a Plasma Impedance Probe (PIP), a Wide-sweep langmuir Probe (WLP), and a Narrow-sweep Langmuir Probe (NLP). This instrument package provides a new opportunity lor collaborative multi-instrument studies of the F-region ionosphere during both quiet and disturbed periods. This presentation first describes the operational parameters for each of the FPMU probes and shOWS examples of an intra-instrument validation. We then show comparisons with the plasma density and temperature measurements derived from the TIMED GUVI ultraviolet imager, the Millstone Hill ground based incoherent scatter radar, and DIAS digisondes, Finally we show one of several observations of night-time equatorial density holes demonstrating the capabilities of the probes lor monitoring mid and low latitude plasma processes.

  19. In-situ Observations of the Ionospheric F2-Region from the International Space Station

    NASA Technical Reports Server (NTRS)

    Coffey, Victoria N.; Wright, Kenneth H.; Minow, Joseph I.; Chandler, Michael O.; Parker, Linda N.

    2008-01-01

    The International Space Station orbit provides an ideal platform for in-situ studies of space weather effects on the mid and low latitude F-2 region ionosphere. The Floating Potential Measurement Unit (FPMU) operating on the ISS since Aug 2006, is a suite of plasma instruments: a Floating Potential Probe (FPP), a Plasma Impedance Probe (PIP), a Wide-sweep Langmuir Probe (WLP), and a Narrow-sweep Langmuir Probe (NLP). This instrument package provides a new opportunity for collaborative multi-instrument studies of the F-region ionosphere during both quiet and disturbed periods. This presentation first describes the operational parameters for each of the FPMU probes and shows examples of an intra-instrument validation. We then show comparisons with the plasma density and temperature measurements derived from the TIMED GUVI ultraviolet imager, the Millstone Hill ground based incoherent scatter radar, and DIAS digisondes, Finally we show one of several observations of night-time equatorial density holes demonstrating the capabilities of the probes for monitoring mid and low latitude plasma processes.

  20. Evidence for o-atom exchange in the O(1D) + N2O reaction as the source of mass-independent isotopic fractionation in atmospheric N2O.

    SciTech Connect

    Miller, Charles E.; Liang, Mao-Chang; Blake, Geoffrey A.; Muller, Richard Partain; Yung, Yuk L.

    2004-07-01

    Recent experiments have shown that in the oxygen isotopic exchange reaction for O({sup 1}D) + CO{sub 2} the elastic channel is approximately 50% that of the inelastic channel [Perri et al., 2003]. We propose an analogous oxygen atom exchange reaction for the isoelectronic O({sup 1}D) + N{sub 2}O system to explain the mass-independent isotopic fractionation (MIF) in atmospheric N{sub 2}O. We apply quantum chemical methods to compute the energetics of the potential energy surfaces on which the O({sup 1}D) + N{sub 2}O reaction occurs. Preliminary modeling results indicate that oxygen isotopic exchange via O({sup 1}D) + N{sub 2}O can account for the MIF oxygen anomaly if the oxygen atom isotopic exchange rate is 30-50% that of the total rate for the reactive channels.

  1. Crystal structure of TBC1D15 GTPase-activating protein (GAP) domain and its activity on Rab GTPases.

    PubMed

    Chen, Yan-Na; Gu, Xin; Zhou, X Edward; Wang, Weidong; Cheng, Dandan; Ge, Yinghua; Ye, Fei; Xu, H Eric; Lv, Zhengbing

    2017-04-01

    TBC1D15 belongs to the TBC (Tre-2/Bub2/Cdc16) domain family and functions as a GTPase-activating protein (GAP) for Rab GTPases. So far, the structure of TBC1D15 or the TBC1D15·Rab complex has not been determined, thus, its catalytic mechanism on Rab GTPases is still unclear. In this study, we solved the crystal structures of the Shark and Sus TBC1D15 GAP domains, to 2.8 Å and 2.5 Å resolution, respectively. Shark-TBC1D15 and Sus-TBC1D15 belong to the same subfamily of TBC domain-containing proteins, and their GAP-domain structures are highly similar. This demonstrates the evolutionary conservation of the TBC1D15 protein family. Meanwhile, the newly determined crystal structures display new variations compared to the structures of yeast Gyp1p Rab GAP domain and TBC1D1. GAP assays show that Shark and Sus GAPs both have higher catalytic activity on Rab11a·GTP than Rab7a·GTP, which differs from the previous study. We also demonstrated the importance of arginine and glutamine on the catalytic sites of Shark GAP and Sus GAP. When arginine and glutamine are changed to alanine or lysine, the activities of Shark GAP and Sus GAP are lost.

  2. Perinatal and Postnatal Expression of Cav1.3 α1D Ca2+ Channel in the Rat Heart

    PubMed Central

    Qu, Yongxia; Karnabi, Eddy; Ramadan, Omar; Yue, Yuankun; Chahine, Mohamed; Boutjdir, Mohamed

    2011-01-01

    The novel Cav1.3 (α1D) L-type Ca2+ channel plays a significant role in sino-atrial, atrioventricular nodes function and in atrial fibrillation. However, the characterization of α1D Ca2+ channel during heart development is very limited. We used real-time RT-PCR, Western blotting and indirect immunostaining to characterize the developmental expression and localization of α1D Ca2+ channel in rat hearts. Both protein and mRNA levels of α1D Ca2+ channel decreased postnatally. Two forms of α1D Ca2+ channel protein (250 kD and 190 kD) were observed, with the full length (250kD) channel protein being predominant in the prenatal stages. Both Western blots and confocal imaging demonstrated that α1D Ca2+ channel protein was expressed in both atria and ventricles at fetal and neonatal stages but was absent in the adult ventricles. Interestingly, α1D Ca2+ channel was also found at the nucleus/perinucleus of immature, but not adult atrial cells. Furthermore, the nuclear staining was reproduced in adult atrial cell line, HL-1 cells, which possess immature properties. The data are first to show that α1D Ca2+ channel has unique age-dependent expression profile and subcellular localization in the heart, suggesting a developmental stage dependent specific function. PMID:21378599

  3. 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...

  4. 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...

  5. Laser flash photolysis of ozone - O/1D/ quantum yields in the fall-off region 297-325 nm

    NASA Technical Reports Server (NTRS)

    Brock, J. C.; Watson, R. T.

    1980-01-01

    The wavelength dependence of the quantum yield for O(1D) production from ozone photolysis has been determined between 297.5 nm and 325 nm in order to resolve serious discrepancies among previous studies. The results of this investigation are compared to earlier work by calculating atmospheric production rate constants for O(1D). It is found that for the purpose of calculating this rate constant, there is now good agreement among three studies at 298 K. Furthermore, it appears that previous data on the temperature dependence of the O(1D) quantum yield fall-off is adequate for determining the vertical profile of the O(1D) production rate constant. Several experimental difficulties associated with using NO2(asterisk) chemiluminescence to monitor O(1D) have been identified.

  6. 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.

  7. Atomic layer deposition of 1D and 2D nickel nanostructures on graphite.

    PubMed

    Ryu, Seung Wook; Yoon, Jaehong; Moon, Hyoung-Seok; Shong, Bonggeun; Kim, Hyungjun; Lee, Han-Bo-Ram

    2017-03-17

    One-dimensional (1D) nanowires (NWs) and two-dimensional (2D) thin films of Ni were deposited on highly ordered pyrolytic graphite (HOPG) by atomic layer deposition (ALD), using NH3 as a counter reactant. Thermal ALD using NH3 gas forms 1D NWs along step edges, while NH3 plasma enables the deposition of a continuous 2D film over the whole surface. The lateral and vertical growth rates of the Ni NWs are numerically modeled as a function of the number of ALD cycles. Pretreatment with NH3 gas promotes selectivity in deposition by the reduction of oxygenated functionalities on the HOPG surface. On the other hand, NH3 plasma pretreatment generates surface nitrogen species, and results in a morphological change in the basal plane of graphite, leading to active nucleation across the surface during ALD. The effects of surface nitrogen species on the nucleation of ALD Ni were theoretically studied by density functional theory calculations. Our results suggest that the properties of Ni NWs, such as their density and width, and the formation of Ni thin films on carbon surfaces can be controlled by appropriate use of NH3.

  8. A facile route for 3D aerogels from nanostructured 1D and 2D materials

    NASA Astrophysics Data System (ADS)

    Jung, Sung Mi; Jung, Hyun Young; Dresselhaus, Mildred S.; Jung, Yung Joon; Kong, Jing

    2012-11-01

    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.

  9. 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.

  10. A computational investigation on the mechanism of the reaction between O( 1D) and NF 3

    NASA Astrophysics Data System (ADS)

    Antoniotti, Paola; Grandinetti, Felice

    2002-12-01

    The mechanism of the reaction between O( 1D) and NF 3, experimentally studied by spectroscopic techniques [V.I. Sorokin, N.P. Gritsan, A.I. Chichinin, J. Chem. Phys. 108 (1998) 8995], has been investigated at the Coupled Cluster level of theory in conjunction with double-zeta and triple-zeta quality basis sets. The process commences by the exoergic (105.4 kcal mol -1) formation, on the singlet surface, of the O-NF 3 intermediate, whose eventual dissociation into NF 2 and OF passes through the isomerization to F 2N-OF. The energy barrier of this process, 58.8 kcal mol -1, is significantly lower than the intersystem crossing from the singlet O-NF 3 to the triplet O( 3P) and NF 3 dissociation products. This is consistent with the experimental observation that, in the reaction between O( 1D) and NF 3, the unreactive quenching to O( 3P) represents only a minor reaction channel.

  11. 1d, 2d, and 3d periodic structures: Electromagnetic characterization, design, and measurement

    NASA Astrophysics Data System (ADS)

    Brockett, Timothy John

    Periodic structures have many useful applications in electromagnetics including phased arrays, frequency selective surfaces, and absorbing interfaces. Their unique properties can be used to provide increased performance in antenna gain, electromagnetic propagation, and electromagnetic absorption. In antenna arrays, repeating elements create a larger eective aperture, increasing the gain of the antenna and the ability to scan the direction of the main beam. Three-dimensional periodic structures, such as an array of shaped pillars such as columns, cones, or prisms have the potential of improving electromagnetic absorption, improving performance in applications such as solar cell eciency and absorbing interfaces. Furthermore, research into periodic structures is a continuing endeavor where novel approaches and analysis in appropriate applications can be sought. This dissertation will address the analysis, diagnostics, and enhancement of 1D, 2D, and 3D periodic structures for antenna array applications and solar cell technology. In particular, a unique approach to array design will be introduced to prevent the appearance of undesirable grating lobes in large antenna arrays that employ subarrays. This approach, named the distortion diagnostic procedure, can apply directly to 1D and 2D periodic structures in the form of planar antenna arrays. Interesting corollaries included here are developments in millimeter-wave antenna measurements including spiral planar scanning, phaseless measurements, and addressing antennas that feature an internal source. Finally, analysis and enhancement of 3D periodic structures in nanostructure photovoltaic arrays and absorbing interfaces will be examined for their behavior and basic operation in regards to improved absorption of electromagnetic waves.

  12. Developing a 1D ``like'' performance basecamp for beryllium capsule implosions

    NASA Astrophysics Data System (ADS)

    Kline, John; Yi, Austin; Loomis, Eric; Simakov, Andrei; Kyrala, George; Wilson, Doub; Dewald, Eddie; Ralph, Joe; Strozzi, David

    2016-10-01

    Experiments with Beryllium capsules in high density gas filled targets showed little difference in performance with respect to CH or HDC capsules. The hypothesis for the lack of performance difference is attributed to poor control of symmetry based on work by Clark et al. Going forward, the goal is to develop a target design that enables better comparisons between the performance of Be capsules and other ablators, as well as with simulations. To develop a platform in which Be capsules maximize performance with respect to 1D calculations, we have increased the case-to-capsule ratio and reduced the hohlraum drive. The stability properties of beryllium are expected to be accentuated at lower radiation temperature drives compared with other ablators. Experiments have been carried out with case-to-capasule ratio of 3.1 and 4.3. Results from these experiments are being used to develop an optimized case-to-capsule ratio to achieve controllable symmetric implosions with maximum 1D like performance. This presentation will focus on how results of the experiments are used to design the next series of optimized experiments..

  13. Evaluation of 2 1-D cloud models for the analysis of VAS soundings

    NASA Technical Reports Server (NTRS)

    Emmitt, G. D.

    1984-01-01

    Evaluation of the satellite Visual Infrared Spin Scan Radiometer Atmospheric Sounder (VISSR) has begun to document several of its critical shortcomings as far as numerical cloud models are concerned: excessive smoothing of thermal inversions; imprecise measurement of boundary layer moisture; and tendency to exaggerate atmospheric stability. The sensitivity of 1-D cloud models to their required inputs is stressed with special attention to those parameters obtained from atmospheric soundings taken by the VAS or rawinsonde. In addition to performing model experiments using temperature and moisture profiles having the general characteristics of VAS soundings, standard input sensitivity tests were made and 1-D model performance was compared with observations and the results of a 2-D model experiment using AVE/VAS data (Atmospheric Variability Experiment). Although very encouraging, the results are not sufficient to make any specific conclusions. In general, the VAS soundings are likely to be inadequate to provide the cloud base (and subcloud layer) information needed for inputs to current cumulus models. Above cloud base, the tendency to exaggerate the stability of the atmosphere requires solution before meaningful model experiments are run.

  14. Computation of 1-D shock structure using nonlinear coupled constitutive relations and generalized hydrodynamic equations

    NASA Astrophysics Data System (ADS)

    Zhao, Wenwen; Jiang, Zhongzheng; Chen, Weifang

    2016-11-01

    The moment methods in rarefied gas dynamics could be divided into generalized hydrodynamic equations (GHE) and extended hydrodynamic equations (EHE), e.g., Burnett equations, Grad equations and R-13 equations, theoretically. Eu firstly developed the GHE based on a non-equilibrium canonical distribution function and demonstrated the thermodynamically consistent of this model. Subsequently, nonlinear coupled constitutive relations (NCCR) was proposed by Myong by omitting the product of heat flux and velocity gradient in GHE to reduce the computational complexity. According to the successful application in 1-D shock wave structure and 2-D flat plate flow, the capability of NCCR has already been demonstrated successfully. The motivation of this study was to investigate the different behavior of NCCR and GHE for monatomic and diatomic gases in one-dimensional shock structure problems. Therefore, argon and nitrogen shock structure was calculated using both GHE and NCCR model up to Ma=50. The 3rd order MUSCL scheme for inviscid term and the 2nd order central difference scheme for viscid scheme were employed to carry out the computations. Finally, the present results including shock wave profile and its qualitative properties by NCCR and GHE are compared with that of DSMC and NS equations. The results showed that the GHE yield 1-D shock wave in much closer agreement with DSMC results than do the NCCR model without considering the computational complexity and efficiency in present cases.

  15. Multiscale Modeling Techniques for Plasma: 1D Scaling Results and Application to Magnetic Reconnection

    NASA Astrophysics Data System (ADS)

    Shay, Michael; Drake, J.

    2005-10-01

    We examine a novel simulation scheme called ``equation free projective integration'' which has the potential to allow global simulations which still include microscale physics, a necessary ingredient in order to model multiscale problems. Such codes could be used to examine the global effects of reconnection and turbulence in tokamaks, the Earth's magnetosphere, and the solar corona. Using this method to simulate the propagation and steepening of a 1D ion acoustic wave, we have already achieved excellent agreement between full particle codes and equation free with a factor of 20 speed-up. In this method of simulation, the global plasma variables stepped forward in time are not time-integrated directly using dynamical differential equations, hence the name ``equation free.'' Instead, these variables are represented on a microgrid using a kinetic simulation. This microsimulation is integrated forward long enough to determine the time derivatives of the global plasma variables, which are then used to integrate forward the global variables with much larger timesteps. Results will be presented of the successful application of equation free to 1-D ion acoustic wave steepening with a PIC code serving as the underlying kinetic model. Initial results of this technique applied to magnetic reconnection will also be discussed.

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

    NASA Astrophysics Data System (ADS)

    Zhang, Yingjie; Bhadbhade, Mohan; Karatchevtseva, Inna; Price, Jason R.; Liu, Hao; Zhang, Zhaoming; Kong, Linggen; Čejka, Jiří; Lu, Kim; Lumpkin, Gregory R.

    2015-03-01

    Three new coordination polymers of uranium(VI) with pyromellitic acid (H4btca) have been synthesized and structurally characterized. (ED)[(UO2)(btca)]·(DMSO)·3H2O (1) (ED=ethylenediammonium; DMSO=dimethylsulfoxide) has a lamellar structure with intercalation of ED and DMSO. (NH4)2[(UO2)6O2(OH)6(btca)]·~6H2O (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). [(UO2)2(H2O)(btca)]·4H2O (3) has a 3D network constructed by two types of 7-fold coordinated uranium polyhedron. The unique μ5-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.

  17. VizieR Online Data Catalog: 1D Lya forest power spectrum (Palanque-Delabrouille+, 2013)

    NASA Astrophysics Data System (ADS)

    Palanque-Delabrouille, N.; Yeche, C.; Borde, A.; Le Goff, J.-M.; Rossi, G.; Viel, M.; Aubourg, E.; Bailey, S.; Bautista, J.; Blomqvist, M.; Bolton, A.; Bolton, J. S.; Busca, N. G.; Carithers, B.; Croft, R. A. C.; Dawson, K. S.; Delubac, T.; Font-Ribera, A.; Ho, S.; Kirkby, D.; Lee, K.-G.; Margala, D.; Miralda-Escude, J.; Muna, D.; Myers, A. D.; Noterdaeme, P.; Paris, I.; Petitjean, P.; Pieri, M. M.; Rich, J.; Rollinde, E.; Ross, N. P.; Schlegel, D. J.; Schneider, D. P.; Slosar, A.; Weinberg, D. H.

    2013-09-01

    The files contain the data describing the measured 1D power spectrum and the correlations between bins from the BOSS Lyman-alpha data. table4a.dat and table5a.dat: P1D results obtained with the Fourier transform and the likelihood method respectively, for each k and z bin. cct4b*.dat and cct5b*.dat: Correlation matrices between k bins for each z bin, for the Fourier transform and the likelihood method respectively. There are 12 HDUs, one for each redshift bin from =2.2 (HDU 1, table[45]b1.dat) to =4.4 (HDU 12, table[45]b12.dat). Each HDU contains a binary table with 35 bins x 35 entries for the Fourier transform method, and 32 bins x 32 entries for the likelihood method. The tables contain the correlation coefficients. The scale ki corresponding to entry (or bin) i can be read in the corresponding entry of table4a.dat or table5a.dat. (30 data files).

  18. 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.

  19. Design method for a laser line beam shaper of a general 1D angular power distribution

    NASA Astrophysics Data System (ADS)

    Oved, E.; Oved, A.

    2016-05-01

    Laser line is a beam of laser, spanned in one direction using a beam shaper to form a fan of light. This illumination tool is important in laser aided machine vision, 3D scanners, and remote sensing. For some applications the laser line should have a specific angular power distribution. If the distribution is nonsymmetrical, the beam shaper is required to be nonsymmetrical freeform, and its design process using optical design software is time consuming due to the long optimization process which usually converges to some local minimum. In this paper we introduce a new design method of a single element refractive beam shaper of any predefined general 1D angular power distribution. The method makes use of a notion of "prism space", a geometrical representation of all double refraction prisms, and any 1D beam shaper can be described by a continuous curve in this space. It is shown that infinitely many different designs are possible for any given power distribution, and it is explained how an optimal design is selected among them, based on criteria such as high transmission, low surface slopes, robustness to manufacturing errors etc. The method is non-parametric and hence does not require initial guess of a functional form, and the resultant optical surfaces are described by a sequence of points, rather than by an analytic function.

  20. 1D Measurement of Sodium Ion Flow in Hydrogel After a Bath Concentration Jump.

    PubMed

    Roos, R W; Pel, L; Huinink, H P; Huyghe, J M

    2015-07-01

    NMR is used to measure sodium flow driven by a 1D concentration gradient inside poly-acrylamid (pAA) hydrogel. A sodium concentration jump from 0.5 M NaCl to 0 M NaCl is applied at the bottom of a cylindrical pAA sample. The sodium level and hydrogen level are measured as a function of time and position inside the sample for 5 days. Then a reversed step is applied, and ion flow is measured for another 5 days. During the measurement, the cylindrical sample is radially confined and allowed to swell in the axial direction. At the same time, sodium and moisture in the sample are measured on a 1D spatial grid in the axial direction. A quadriphasic mixture model (Huyghe and Janssen in Int J Eng Sci 35:793, 1997) is used to simulate the results and estimate the diffusion coefficient of sodium and chloride. The best fit results were obtained for D[Formula: see text] cm(2)/s and D[Formula: see text] cm(2)/s, at 25 degrees centigrade. Different time constants were observed for swelling and deswelling.

  1. (7)Li in situ 1D NMR imaging of a lithium ion battery.

    PubMed

    Klamor, S; Zick, K; Oerther, T; Schappacher, F M; Winter, M; Brunklaus, G

    2015-02-14

    The spatial distribution of charge carriers in lithium ion batteries during current flow is of fundamental interest for a detailed understanding of transport properties and the development of strategies for future improvements of the electrolyte-electrode interface behaviour. In this work we explored the potential of (7)Li 1D in situ NMR imaging for the identification of concentration gradients under constant current load in a battery cell. An electrochemical cell based on PTFE body and a stack of glass microfiber discs that are soaked with a technically relevant electrolyte suitable for high-temperature application and squeezed between a Li metal and a nano-Si-graphite composite electrode was assembled to acquire (7)Li 1D in situ NMR profiles with an improved NMR pulse sequence as function of time and state of charge, thereby visualizing the course of ion concentration during charge and discharge. Surface localized changes of Li concentration were attributed to processes such as solid electrolyte interphase formation or full lithiation of the composite electrode. The method allows the extraction of lithium ion transport properties.

  2. 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.

  3. Reduced synaptic vesicle protein degradation at lysosomes curbs TBC1D24/sky-induced neurodegeneration.

    PubMed

    Fernandes, Ana Clara; Uytterhoeven, Valerie; Kuenen, Sabine; Wang, Yu-Chun; Slabbaert, Jan R; Swerts, Jef; Kasprowicz, Jaroslaw; Aerts, Stein; Verstreken, Patrik

    2014-11-24

    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.

  4. 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

  5. A mass-conservative finite volume predictor-corrector solution of the 1D Richards' equation

    NASA Astrophysics Data System (ADS)

    Lai, Wencong; Ogden, Fred L.

    2015-04-01

    Numerical solution of the Richards' equation (RE) in variably saturated soils continues to be a challenge due to its highly non-linear behavior. This is particularly true as soils approach saturation and the behavior of the fundamental partial differential equation changes from elliptic to parabolic. In this paper, a finite volume predictor-corrector method with adaptive time-stepping was developed to solve the 1D vertical RE. The numerical method was mass-conservative and non-iterative. In the predictor step, the pressure head-based form of the RE was solved using the cell-centered finite volume method and the pressure head was updated. In the corrector step, the soil water content was calculated by solving the mixed form RE. Five different schemes to evaluate the inter-cell hydraulic conductivity were investigated. The robustness and accuracy of the numerical model were demonstrated through simulation of experimental tests, including free drainage, field infiltration into wet and dry soils, and laboratory infiltration with falling water table. Numerical results were compared against laboratory measurements, simulation results from the Hydrus-1D program, or analytical solution when available. Results showed that the developed scheme is robust and accurate in simulating variably saturated flows with various boundary conditions. The arithmetic mean and Szymkiewicz's mean of inter-cell hydraulic conductivity performed better than other methods especially in the case of infiltration into very dry soil.

  6. SNARK09 - a software package for reconstruction of 2D images from 1D projections.

    PubMed

    Klukowska, Joanna; Davidi, Ran; Herman, Gabor T

    2013-06-01

    The problem of reconstruction of slices and volumes from 1D and 2D projections has arisen in a large number of scientific fields (including computerized tomography, electron microscopy, X-ray microscopy, radiology, radio astronomy and holography). Many different methods (algorithms) have been suggested for its solution. In this paper we present a software package, SNARK09, for reconstruction of 2D images from their 1D projections. In the area of image reconstruction, researchers often desire to compare two or more reconstruction techniques and assess their relative merits. SNARK09 provides a uniform framework to implement algorithms and evaluate their performance. It has been designed to treat both parallel and divergent projection geometries and can either create test data (with or without noise) for use by reconstruction algorithms or use data collected by another software or a physical device. A number of frequently-used classical reconstruction algorithms are incorporated. The package provides a means for easy incorporation of new algorithms for their testing, comparison and evaluation. It comes with tools for statistical analysis of the results and ten worked examples.

  7. 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.

  8. Spin-Polarized Fermi Gases in 1D, 3D, and Crossover Regimes

    NASA Astrophysics Data System (ADS)

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

    2015-05-01

    We report recent results on mapping the superfluid transition as a function of atomic interaction and global spin polarization in a two-component, 3D gas of fermionic lithium. The atomic interactions are controlled using a Feshbach resonance to tune between the strongly interacting BEC regime and the weakly interacting BCS regime. Previously, a 3D gas was found to have an unpolarized superfluid core that is enclosed by polarized shells. By applying a 2D optical lattice we confine our gas in one-dimensional tubes. In this 1D gas, in contrast to the 3D gas, we found a partially polarized superfluid core and either fully polarized or fully paired wings depending on the overall spin polarization. In the current experiment, we have mapped the phase diagram of the 1D/3D crossover by increasing the inter-tube coupling. The exotic superfluid state, FFLO, is predicted to occupy a large portion of the phase diagram in the crossover regime, making it an ideal location in parameter space for its detection. ARO, NSF, ONR, and The Welch Foundation.

  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. Atomic layer deposition of 1D and 2D nickel nanostructures on graphite

    NASA Astrophysics Data System (ADS)

    Ryu, Seung Wook; Yoon, Jaehong; Moon, Hyoung-Seok; Shong, Bonggeun; Kim, Hyungjun; Lee, Han-Bo-Ram

    2017-03-01

    One-dimensional (1D) nanowires (NWs) and two-dimensional (2D) thin films of Ni were deposited on highly ordered pyrolytic graphite (HOPG) by atomic layer deposition (ALD), using NH3 as a counter reactant. Thermal ALD using NH3 gas forms 1D NWs along step edges, while NH3 plasma enables the deposition of a continuous 2D film over the whole surface. The lateral and vertical growth rates of the Ni NWs are numerically modeled as a function of the number of ALD cycles. Pretreatment with NH3 gas promotes selectivity in deposition by the reduction of oxygenated functionalities on the HOPG surface. On the other hand, NH3 plasma pretreatment generates surface nitrogen species, and results in a morphological change in the basal plane of graphite, leading to active nucleation across the surface during ALD. The effects of surface nitrogen species on the nucleation of ALD Ni were theoretically studied by density functional theory calculations. Our results suggest that the properties of Ni NWs, such as their density and width, and the formation of Ni thin films on carbon surfaces can be controlled by appropriate use of NH3.

  11. Dephosphorylation of 1D-myo-inositol 1,4-bisphosphate in rat liver.

    PubMed Central

    Morris, A J; Storey, D J; Downes, C P; Michell, R H

    1988-01-01

    Dephosphorylation of 1D-myo-inositol 1,4-bisphosphate [Ins(1,4)P2] in rat liver is catalysed by a cytosolic phosphatase that removes the 1-phosphate group. The Km for Ins(1,4)P2 is approx. 17 microM. Li+ (100 mM) causes 50% inhibition of Ins(1,4)P2 phosphatase activity when activity is measured at the very low substrate concentration of 10 nM, but on raising the substrate concentration to 100 microM there is a greater than 10-fold increase in sensitivity to Li+, suggesting that Li+ acts mainly, but not entirely, as an uncompetitive inhibitor of Ins(1,4)P2 phosphatase. In addition, rat liver cytosol shows Li+-sensitive phosphatase activity against 1D-myo-inositol 1-,3- and 4-monophosphates. The Ins(1,4)P2 1-phosphatase and inositol monophosphatase activities all share an apparent Mr of 47 x 10(3), as determined by gel-filtration chromatography. However, the Ins(1,4)P2 1-phosphatase is more sensitive to inactivation by heat, and can be separated from inositol monophosphatase activity by anion-exchange chromatography. We conclude that rat liver cytosol contains an Ins(1,4)P2 1-phosphatase that is distinct from, but in many ways similar to, inositol monophosphatase. PMID:2848493

  12. D1/D5 dopamine receptors stimulate intracellular calcium release in primary cultures of neocortical and hippocampal neurons.

    PubMed

    Lezcano, Nelson; Bergson, Clare

    2002-04-01

    D1/D5 dopamine receptors in basal ganglia, hippocampus, and cerebral cortex modulate motor, reward, and cognitive behavior. Previous work with recombinant proteins revealed that in cells primed with heterologous G(q/11)-coupled G-protein-coupled receptor (GPCR) agonists, the typically G(s)-linked D1/D5 receptors can stimulate robust release of calcium from internal stores when coexpressed with calcyon. To learn more about the intracellular signaling mechanisms underlying these D1/D5 receptor regulated behaviors, we explored the possibility that endogenous receptors stimulate internal release of calcium in neurons. We have identified a population of neurons in primary cultures of hippocampus and neocortex that respond to D1/D5 dopamine receptor agonists with a marked increase in intracellular calcium (Ca) levels. The D1/D5 receptor stimulated responses occurred in the absence of extracellular Ca(2+) indicating the rises in Ca involve release from internal stores. In addition, the responses were blocked by D1/D5 receptor antagonists. Further, the D1/D5 agonist-evoked responses were state dependent, requiring priming with agonists of G(q/11)-coupled glutamate, serotonin, muscarinic, and adrenergic receptors or with high external K(+) solution. In contrast, D1/D5 receptor agonist-evoked Ca(2+) responses were not detected in neurons derived from striatum. However, D1/D5 agonists elevated cAMP levels in striatal cultures as effectively as in neocortical and hippocampal cultures. Further, neither forskolin nor 8-Br-cAMP stimulation following priming was able to mimic the D1/D5 agonist-evoked Ca(2+) response in neocortical neurons indicating that increased cAMP levels are not sufficient to stimulate Ca release. Our data suggest that D1-like dopamine receptors likely modulate neocortical and hippocampal neuronal excitability and synaptic function via Ca(2+) as well as cAMP-dependent signaling.

  13. Design and synthesis of new 1D and 2D R-isophthalic acid-based coordination polymers (R = hydrogen or bromine).

    PubMed

    Zhang, Ren; Gong, Qihan; Emge, Thomas J; Banerjee, Debasis; Li, Jing

    2013-01-01

    Three new R-isophthalic acid-based (R = H or Br) coordination polymers have been designed and synthesized. By changing the N-containing ligand in the system, we are able to tune the dimensionality of coordination polymers from one-dimension (1D) to two-dimensions (2D) with the same basic building unit. Also, different metal ions can be incorporated into the same structures. Compound 1 [Cu(bipa)(py)2]·0.5(H2O) (H2bipa = 5-bromoisophthalic acid; py = pyridine) and compound 2 [Co(bipa)(py)2] are 1D chain structures. Compound 3 [Cu8(ipa)8(bpe)8]·2(bpe)·4(H2O) (bpe=1,2-bis(4-pyridyl)ethane) is a 2D layered structure.

  14. Distribution of interneurons in the CA2 region of the rat hippocampus

    PubMed Central

    Botcher, Nicola A.; Falck, Joanne E.; Thomson, Alex M.; Mercer, Audrey

    2014-01-01

    The CA2 region of the mammalian hippocampus is a unique region with its own distinctive properties, inputs and pathologies. Disruption of inhibitory circuits in this region appears to be linked with the pathology of specific psychiatric disorders, promoting interest in its local circuitry, its role in hippocampal function and its dysfunction in disease. In previous studies, CA2 interneurons, including a novel subclass of CA2 dendrite-preferring interneurons that has not been identified in other CA regions, have been shown to display physiological, synaptic and morphological properties unique to this sub-field and may therefore play a crucial role in the hippocampal circuitry. The distributions of immuno-labeled interneurons in dorsal CA2 were studied and compared with those of interneurons in CA1 and CA3. Like those in CA1 and CA3, the somata of CA2 parvalbumin-immunoperoxidase-labeled interneurons were located primarily in Stratum Pyramidale (SP) and Stratum Oriens (SO), with very few cells in Stratum Radiatum (SR) and none in Stratum Lacunosum Moleculare (SLM). There was, however, a greater proportion of GAD-positive cells were immunopositive for PV in SP in CA2 than in CA1 or CA3. CA2 SP also contained a larger density of somatostatin-, calbindin-, and VIP-immunopositive somata than CA1 and/or CA3. Like those in CA1 and CA3, CCK-immunopositive somata in CA2 were mostly located in SR. Reelin- and NPY- immunolabeled cell bodies were located in all layers of the three CA regions. However, a higher density of Reelin-positive somata was found in SP and SR of CA2 than in CA1 or CA3. PMID:25309345

  15. Estimating the soil organic carbon content for European NUTS2 regions based on LUCAS data collection.

    PubMed

    Panagos, Panos; Ballabio, Cristiano; Yigini, Yusuf; Dunbar, Martha B

    2013-01-01

    Under the European Union Thematic Strategy for Soil Protection, the European Commission Directorate-General for the Environment and the European Environmental Agency (EEA) identified a decline in soil organic carbon and soil losses by erosion as priorities for the collection of policy relevant soil data at European scale. Moreover, the estimation of soil organic carbon content is of crucial importance for soil protection and for climate change mitigation strategies. Soil organic carbon is one of the attributes of the recently developed LUCAS soil database. The request for data on soil organic carbon and other soil attributes arose from an on-going debate about efforts to establish harmonized datasets for all EU countries with data on soil threats in order to support modeling activities and display variations in these soil conditions across Europe. In 2009, the European Commission's Joint Research Centre conducted the LUCAS soil survey, sampling ca. 20,000 points across 23 EU member states. This article describes the results obtained from analyzing the soil organic carbon data in the LUCAS soil database. The collected data were compared with the modeled European topsoil organic carbon content data developed at the JRC. The best fitted comparison was performed at NUTS2 level and showed underestimation of modeled data in southern Europe and overestimation in the new central eastern member states. There is a good correlation in certain regions for countries such as the United Kingdom, Slovenia, Italy, Ireland, and France. Here we assess the feasibility of producing comparable estimates of the soil organic carbon content at NUTS2 regional level for the European Union (EU27) and draw a comparison with existing modeled data. In addition to the data analysis, we suggest how the modeled data can be improved in future updates with better calibration of the model.

  16. Distribution of interneurons in the CA2 region of the rat hippocampus.

    PubMed

    Botcher, Nicola A; Falck, Joanne E; Thomson, Alex M; Mercer, Audrey

    2014-01-01

    The CA2 region of the mammalian hippocampus is a unique region with its own distinctive properties, inputs and pathologies. Disruption of inhibitory circuits in this region appears to be linked with the pathology of specific psychiatric disorders, promoting interest in its local circuitry, its role in hippocampal function and its dysfunction in disease. In previous studies, CA2 interneurons, including a novel subclass of CA2 dendrite-preferring interneurons that has not been identified in other CA regions, have been shown to display physiological, synaptic and morphological properties unique to this sub-field and may therefore play a crucial role in the hippocampal circuitry. The distributions of immuno-labeled interneurons in dorsal CA2 were studied and compared with those of interneurons in CA1 and CA3. Like those in CA1 and CA3, the somata of CA2 parvalbumin-immunoperoxidase-labeled interneurons were located primarily in Stratum Pyramidale (SP) and Stratum Oriens (SO), with very few cells in Stratum Radiatum (SR) and none in Stratum Lacunosum Moleculare (SLM). There was, however, a greater proportion of GAD-positive cells were immunopositive for PV in SP in CA2 than in CA1 or CA3. CA2 SP also contained a larger density of somatostatin-, calbindin-, and VIP-immunopositive somata than CA1 and/or CA3. Like those in CA1 and CA3, CCK-immunopositive somata in CA2 were mostly located in SR. Reelin- and NPY- immunolabeled cell bodies were located in all layers of the three CA regions. However, a higher density of Reelin-positive somata was found in SP and SR of CA2 than in CA1 or CA3.

  17. Tight-Binding Approximations in 1D and 2D Coupled-Cavity Photonic Crystal Structures

    NASA Astrophysics Data System (ADS)

    Day, Nicole C. L.

    Light confinement and controlling an optical field has numerous applications in the field of telecommunications for optical signals processing. When the wavelength of the electromagnetic field is on the order of the period of a photonic microstructure, the field undergoes reflection, refraction, and coherent scattering. This produces photonic bandgaps, forbidden frequency regions or spectral stop bands where light cannot exist. Dielectric perturbations that break the perfect periodicity of these structures produce what is analogous to an impurity state in the bandgap of a semiconductor. The defect modes that exist at discrete frequencies within the photonic bandgap are spatially localized about the cavity-defects in the photonic crystal. In this thesis the properties of two tight-binding approximations (TBAs) are investigated in one-dimensional and two-dimensional coupled-cavity photonic crystal structures. We require an efficient and simple approach that ensures the continuity of the electromagnetic field across dielectric interfaces in complex structures. In this thesis we develop E- and D-TBAs to calculate the modes in finite 1D and 2D two-defect coupled-cavity photonic crystal structures. In the E- and D-TBAs we expand the coupled-cavity [vector electron]-modes in terms of the individual [vector electron]- and [vector D meson]-modes, respectively. We investigate the dependence of the defect modes, their frequencies and quality factors on the relative placement of the defects in the photonic crystal structures. We then elucidate the differences between the two TBA formulations, and describe the conditions under which these formulations may be more robust when encountering a dielectric perturbation. Our 1D analysis showed that the 1D modes were sensitive to the structure geometry. The antisymmetric D mode amplitudes show that the D. TBA did not capture the correct (tangential [vector electron]-field) boundary conditions. However, the D-TBA did not yield

  18. Using 1D theory to understand 3D stagnation of a wire-array Z pinch in the absence of radiation

    NASA Astrophysics Data System (ADS)

    Yu, Edmund

    2015-11-01

    Many high-energy-density systems implode towards the axis of symmetry, where it collides on itself, forming a hot plasma. However, experiments show these imploding plasmas develop three-dimensional (3D) structures. As a result, the plasma cannot completely dissipate its kinetic energy at stagnation, instead retaining significant 3D flow. A useful tool for understanding the effects of this residual flow is 3D simulation, but the amount and complexity of information can be daunting. To address this problem, we explore the connection between 3D simulation and one-dimensional (1D) theory. Such a connection, if it exists, is mutually beneficial: 1D theory can provide a clear picture of the underlying dynamics of 3D stagnation. On the other hand, deviations between theory and simulation suggest how 1D theory must be modified to account for 3D effects. In this work, we focus on a 3D, magnetohydrodynamic simulation of a compact wire-array Z pinch. To provide a simpler background against which to test our ideas, we artificially turn off radiation during the stagnation phase. Examination of the initial accumulation of mass on axis reveals oblique collision between jets, shock accretion, and vortex formation. Despite evidence for shock-dominated stagnation, a 1D shockless stagnation solution is more appropriate for describing the global dynamics, in that it reproduces the increase of on-axis density with time. However, the 1D solution must be modified to account for 3D effects: the flows suggest enhanced thermal transport as well as centrifugal force. Upon reaching peak compression, the stagnation transitions to a second phase, in which the high-pressure core on axis expands outward into the remaining imploding plasma. During this phase, a 1D shock solution describes the growth of the shock accretion region, as well as the decrease of on-axis density with time. However, the effect of 3D flows is still present: the on-axis temperature does not cool during expansion, which

  19. 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

  20. 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.

  1. 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.

  2. Comparison of Students' Ability to Measure Distance using Wavelength in 1D and 2D Settings

    NASA Astrophysics Data System (ADS)

    White, Gary

    2015-03-01

    When physics students are asked to measure the distance between two fixed locations using a concrete object like a pencil, virtually all respond successfully; however, in some settings, when asked to perform a similar measurement using wavelength as a ruler, there is less success, especially if the students are first asked to note that the ``ruler'' to be used is not fixed in length (see ``Is a Simple Measurement Task a Roadblock to Student Understanding of Wave Phenomena?,'' by M. Kryjevskaia, M. Stetzer, and P. Heron, The Physics Teacher 51,560, (2103) and references therein). I will show some data from introductory classes (algebra- and calculus-based) that replicate this latter result, and also show some interesting features when comparing particular 1D and 2D contexts.

  3. 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.

  4. Initial Stage of the Microwave Ionization Wave Within a 1D Model

    NASA Astrophysics Data System (ADS)

    Semenov, V. E.; Rakova, E. I.; Glyavin, M. Yu.; Nusinovich, G. S.

    2016-05-01

    The dynamics of the microwave breakdown in a gas is simulated numerically within a simple 1D model which takes into account such processes as the impact ionization of gas molecules, the attachment of electrons to neutral molecules, and plasma diffusion. Calculations are carried out for different spatial distributions of seed electrons with account for reflection of the incident electromagnetic wave from the plasma. The results reveal considerable dependence of the ionization wave evolution on the relation between the field frequency and gas pressure, as well as on the existence of extended rarefied halo of seed electrons. At relatively low gas pressures (or high field frequencies), the breakdown process is accompanied by the stationary ionization wave moving towards the incident electromagnetic wave. In the case of a high gas pressure (or a relatively low field frequency), the peculiarities of the breakdown are associated with the formation of repetitive jumps of the ionization front.

  5. Controlling Orientational Order in 1-D Assemblies of Multivalent Triangular Prisms.

    PubMed

    Kohlstedt, Kevin L; Olvera de la Cruz, Monica; Schatz, George C

    2013-01-03

    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.

  6. 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.

  7. 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.

  8. Catalyst-nanostructure interaction in the growth of 1-D ZnO nanostructures.

    PubMed

    Borchers, C; Müller, S; Stichtenoth, D; Schwen, D; Ronning, C

    2006-02-02

    Vapor-liquid-solid is a well-established process in catalyst guided growth of 1-D nanostructures, i.e., nanobelts and nanowires. The catalyst particle is generally believed to be in the liquid state during growth, and is the site for impinging molecules. The crystalline structure of the catalyst may not have any influence on the structure of the grown nanostructures. In this work, using Au guided growth of ZnO, we show that the interfaces between the catalyst droplet and the nanostructure grow in well-defined mutual crystallographic relationships. The nanostructure defines the crystallographic orientation of the solidifying Au droplet. Possible alloy, intermetallic, or eutectic phase formation during catalysis are elucidated with the help of a proposed ternary Au-Zn-O phase diagram.

  9. Spatial Nonlocal Pair Correlations in a Repulsive 1D Bose Gas

    SciTech Connect

    Sykes, A. G.; Davis, M. J.; Kheruntsyan, K. V.; Gangardt, D. M.; Viering, K.; Raizen, M. G.

    2008-04-25

    We analytically calculate the spatial nonlocal pair correlation function for an interacting uniform 1D Bose gas at finite temperature and propose an experimental method to measure nonlocal correlations. Our results span six different physical realms, including the weakly and strongly interacting regimes. We show explicitly that the characteristic correlation lengths are given by one of four length scales: the thermal de Broglie wavelength, the mean interparticle separation, the healing length, or the phase coherence length. In all regimes, we identify the profound role of interactions and find that under certain conditions the pair correlation may develop a global maximum at a finite interparticle separation due to the competition between repulsive interactions and thermal effects.

  10. Structural transformation in monolayer materials: a 2D to 1D transformation.

    PubMed

    Momeni, Kasra; Attariani, Hamed; LeSar, Richard A

    2016-07-20

    Reducing the dimensions of materials to atomic scales results in a large portion of atoms being at or near the surface, with lower bond order and thus higher energy. At such scales, reduction of the surface energy and surface stresses can be the driving force for the formation of new low-dimensional nanostructures, and may be exhibited through surface relaxation and/or surface reconstruction, which can be utilized for tailoring the properties and phase transformation of nanomaterials without applying any external load. Here we used atomistic simulations and revealed an intrinsic structural transformation in monolayer materials that lowers their dimension from 2D nanosheets to 1D nanostructures to reduce their surface and elastic energies. Experimental evidence of such transformation has also been revealed for one of the predicted nanostructures. Such transformation plays an important role in bi-/multi-layer 2D materials.

  11. 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

  12. A new subgenotype 2.1d isolates of classical swine fever virus in China, 2014.

    PubMed

    Zhang, Hongliang; Leng, Chaoliang; Feng, Liping; Zhai, Hongyue; Chen, Jiazeng; Liu, Chunxiao; Bai, Yun; Ye, Chao; Peng, Jinmei; An, Tongqing; Kan, Yunchao; Cai, Xuehui; Tian, Zhijun; Tong, Guangzhi

    2015-08-01

    The lapinized attenuated vaccine against classical swine fever (CSF) has been used in China for over half a century and has generally prevented large-scale outbreaks in recent years. However, since late 2014, a large number of new cases of CSF were detected in many immunized pig farms in China. Several of these CSV viruses were isolated and characterized. Phylogenetic and genomic sequence analyses indicate that these new isolates, as well as some reference isolates, form a new subgenotype named 2.1d, and share several consistent molecular characteristics. Since these new isolates emerged in disparate geographic regions within 5 months, this suggests that these isolates may be widespread. Given that current vaccines do not appear to provide effective protection against this new subgenotype, further investigation of these strains is urgently needed.

  13. 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.

  14. Goal-based h-adaptivity of the 1-D diamond difference discrete ordinate method

    NASA Astrophysics Data System (ADS)

    Jeffers, R. S.; Kópházi, J.; Eaton, M. D.; Févotte, F.; Hülsemann, F.; Ragusa, J.

    2017-04-01

    The quantity of interest (QoI) associated with a solution of a partial differential equation (PDE) is not, in general, the solution itself, but a functional of the solution. Dual weighted residual (DWR) error estimators are one way of providing an estimate of the error in the QoI resulting from the discretisation of the PDE. This paper aims to provide an estimate of the error in the QoI due to the spatial discretisation, where the discretisation scheme being used is the diamond difference (DD) method in space and discrete ordinate (SN) method in angle. The QoI are reaction rates in detectors and the value of the eigenvalue (Keff) for 1-D fixed source and eigenvalue (Keff criticality) neutron transport problems respectively. Local values of the DWR over individual cells are used as error indicators for goal-based mesh refinement, which aims to give an optimal mesh for a given QoI.

  15. Method of single expression: an exact solution for wavelength scale 1D photonic structure computer modeling

    NASA Astrophysics Data System (ADS)

    Baghdasaryan, Hovik V.; Knyazyan, Tamara M.

    2003-12-01

    The principles of the method of single expression (MSE) for boundary problems solution in classical electrodynamics are presented. In the MSE the solution of the Helmholtz's equation is presented in the special form of a single expression describing resultant amplitude and phase distributions in the medium. This form of solution presenation permits to pass over the restrictions of the superposition principle and to solve both linear and nonlinear problems with ths same ease. In the MSE the Helmholtz's equation is reformulated to the set of first order differential equations and the boundary problem is solved numerically. No approximations are implied either in Helmholtz's equation or in boundary conditions. Using the MSE steady-state boundary problems are modeled for wavelength scale multilayer and modulated 1D photonic structures including amplification and nonuniformity evoked by intense electromagnetic field.

  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. Molecular tectonics: on the formation of 1-D silver coordination networks by thiacalixarenes bearing nitrile groups.

    PubMed

    Kozlova, Marina N; Ferlay, Sylvie; Solovieva, Svetlana E; Antipin, Igor S; Konovalov, Alexander I; Kyritsakas, Nathalie; Hosseini, Mir Wais

    2007-11-28

    Two new p-tert-butylthiacalix[4]arene derivatives 2 and 3 decorated at the lower rim with four nitrile groups have been prepared and structurally characterised in the crystalline phase. The two ligands, differing by the length of the spacer between the calix moiety and the nitrile group, adopt the 1,3-alternate conformation in the solid state. The ligand 3 bearing four (CH(2))(3)CN fragments behaves as a tecton in the presence of silver salts (AgX, X = BF(4), PF(6) or SbF(6)) and leads to the formation of analogous 1-D linear coordination networks. The tecton 3 acts as a bischelate unit and bridges consecutive silver cations adopting a tetrahedral coordination geometry. Anions and solvent molecules occupy the free space between networks and exhibit no specific interactions with the cationic architecture.

  18. Formation of Gd coordination polymer with 1D chains mediated by Bronsted acidic ionic liquids

    NASA Astrophysics Data System (ADS)

    Luo, Qianqian; Han, Ying; Lin, Hechun; Zhang, Yuanyuan; Duan, Chungang; Peng, Hui

    2017-03-01

    One dimensional coordination polymer Gd[(SO4)(NO3)(C2H6SO)2] (1) is prepared through the mediation of Bronsted acid ionic liquid, which crystallized in the monoclinic space of C2/c. In this polymer, adjacent Gd atoms are linked by two SO42- ions to generate a 1-D chain, and all oxygen atoms in SO42- groups are connected to three nearest Gd atoms in μ3:η1:η1:η2 fashion. Gd, S and N from SO42- and NO3- are precisely coplanar. The planar is coordinated by a pair of DMSO molecules, which is parallel and linked by hydrogen bonding to form a three-dimensional supramolecular network. Magnetic susceptibility measurement of 1 reveals weak antiferromagnetic interactions between the Gd (III) ions. It exhibits relatively large magneto-caloric effect with -ΔSm=28.8 J Kg-1 K-1 for ΔH=7 T.

  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. 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.

  1. Harnessing the Efficiency of 0(1D) Insertion Reactions for Prebiotic Astrochemistry

    NASA Astrophysics Data System (ADS)

    Widicus Weaver, Susanna

    We propose a THz spectroscopic study of the small prebiotic molecules aminomethanol, methanediol, and methoxymethanol. These target molecules are predicted as the dominant products of photo-driven grain surface chemistry in interstellar environments, and are precursors to important prebiotic molecules like sugars and amino acids. These molecules are also expected to be major contributors to the spectral line density in the submillimeter spectral surveys from the Herschel and SOFIA observatories. We will use our custom mixing source to produce these molecules through O(1D) insertion reactions with the precursor molecules methyl amine, methanol, and dimethyl ether, respectively. We will then record their rotational spectra across the THz frequency range using our existing submillimeter spectrometer. This research will increase the science return from NASA missions because the target molecules serve as tracers of the simplest organic chemistry that can occur in starforming regions. This chemistry begins with methanol, which is the predominant organic molecule observed in interstellar ices. Methanol photodissociation leads to small organic radicals such as CH3O, CH2OH, and CH3. These radicals can undergo combination reactions on interstellar ices to form many of the complex organic molecules that are routinely observed in star-forming regions. Our target molecules aminomethanol, methanediol, and methoxymethanol are some of the simplest molecules that can form from this type of chemistry, and serve as tracers of ice mantle liberation in star-forming regions. These molecules also participate in gas-phase reactions that lead to amino acids and sugars, and as such are fundamentally important prebiotic molecules in interstellar environments. These types of small organic molecules also have high spectral line density, and are major contributors to line confusion in observational spectral surveys such as those conducted by Herschel and SOFIA. Therefore, the proposed research

  2. 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.

  3. 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.

  4. Reticular synthesis of porous molecular 1D nanotubes and 3D networks

    NASA Astrophysics Data System (ADS)

    Slater, A. G.; Little, M. A.; Pulido, A.; Chong, S. Y.; Holden, D.; Chen, L.; Morgan, C.; Wu, X.; Cheng, G.; Clowes, R.; Briggs, M. E.; Hasell, T.; Jelfs, K. E.; Day, G. M.; Cooper, A. I.

    2017-01-01

    Synthetic control over pore size and pore connectivity is the crowning achievement for porous metal-organic frameworks (MOFs). The same level of control has not been achieved for molecular crystals, which are not defined by strong, directional intermolecular coordination bonds. Hence, molecular crystallization is inherently less controllable than framework crystallization, and there are fewer examples of 'reticular synthesis', in which multiple building blocks can be assembled according to a common assembly motif. Here we apply a chiral recognition strategy to a new family of tubular covalent cages to create both 1D porous nanotubes and 3D diamondoid pillared porous networks. The diamondoid networks are analogous to MOFs prepared from tetrahedral metal nodes and linear ditopic organic linkers. The crystal structures can be rationalized by computational lattice-energy searches, which provide an in silico screening method to evaluate candidate molecular building blocks. These results are a blueprint for applying the 'node and strut' principles of reticular synthesis to molecular crystals.

  5. Fermi Liquid Behavior in Quasi 1-D Conductors via Angular Magnetoresistance Oscillations

    NASA Astrophysics Data System (ADS)

    Lee, I. J.; Naughton, M. J.

    1998-03-01

    A body of evidence appears to be developing which suggests that electronic conduction in the q1D TMTSF molecular conductors can not be explained solely by Fermi liquid theory. Recent magnetotransport(G.M. Danner and P.M. Chaikin, Phys. Rev. Lett., 75), 4690 (1995). and photoemission(F. Zwick, et al. al.,) Phys. Rev. Lett., 79, 3982 (1997). experiments even point to a lack of a Fermi surface. We present angular-dependent magnetoresistance data on (TMTSF)_2PF6 under pressure, accompanied by calculations/simulations based on Boltzman transport (which explicitly require the existence of a Fermi surface). Based on rather good agreement between the two results, we maintain that a Fermi liquid description works, at least for the pressures employed. We will attempt to define the parameter space where Fermi liquid theory works, and where other (e.g. Luttinger) theories may be required.

  6. Theoretical studies on the reaction mechanism of O( 1D) with CH 3OCF 3

    NASA Astrophysics Data System (ADS)

    Liu, Hong-Xia; Liu, Jing-Yao; Zhang, Gang; Sun, Chia-Chung

    2009-03-01

    A detailed quantum chemical study was performed at the BMC-CCSD//B3LYP/6-311G(d,p) level to explore the mechanism of the O( 1D) + CH 3OCF 3 reaction. Three feasible initial association intermediates ( a, b, and c) and six energetically allowed paths are located. Our calculations show that the primary products are P 2 and P 3, while P 1, P 4, and P 6 are less competitive. Due to the low-lying intermediates and transition states involved in the dominant paths, the reaction is expected to occur rapidly, which is consistent with the experimental measurement. The present theoretical studies may provide useful information on the issues of the reaction mechanism and product distributions.

  7. 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.

  8. Mixed-mode crack tip loading and crack deflection in 1D quasicrystals

    NASA Astrophysics Data System (ADS)

    Wang, Zhibin; Scheel, Johannes; Ricoeur, Andreas

    2016-12-01

    Quasicrystals (QC) are a new class of materials besides crystals and amorphous solids and have aroused much attention of researchers since they were discovered. This paper presents a generalized fracture theory including the J-integral and crack closure integrals, relations between J1, J2 and the stress intensity factors as well as the implementation of the near-tip stress and displacement solutions of 1D QC. Different crack deflection criteria, i.e. the J-integral and maximum circumferential stress criteria, are investigated for mixed-mode loading conditions accounting for phonon-phason coupling. One focus is on the influence of phason stress intensity factors on crack deflection angles.

  9. One-electron singular spectral features of the 1D Hubbard model at finite magnetic field

    NASA Astrophysics Data System (ADS)

    Carmelo, J. M. P.; Čadež, T.

    2017-01-01

    The momentum, electronic density, spin density, and interaction dependences of the exponents that control the (k , ω)-plane singular features of the σ = ↑ , ↓ one-electron spectral functions of the 1D Hubbard model at finite magnetic field are studied. The usual half-filling concepts of one-electron lower Hubbard band and upper Hubbard band are defined in terms of the rotated electrons associated with the model Bethe-ansatz solution for all electronic density and spin density values and the whole finite repulsion range. Such rotated electrons are the link of the non-perturbative relation between the electrons and the pseudofermions. Our results further clarify the microscopic processes through which the pseudofermion dynamical theory accounts for the one-electron matrix elements between the ground state and excited energy eigenstates.

  10. 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.

  11. Analytical solutions for some defect problems in 1D hexagonal and 2D octagonal quasicrystals

    NASA Astrophysics Data System (ADS)

    Wang, X.; Pan, E.

    2008-05-01

    We study some typical defect problems in one-dimensional (1D) hexagonal and two-dimensional (2D) octagonal quasicrystals. The first part of this investigation addresses in detail a uniformly moving screw dislocation in a 1D hexagonal piezoelectric quasicrystal with point group 6mm. A general solution is derived in terms of two functions \\varphi_1, \\varphi_2, which satisfy wave equations, and another harmonic function \\varphi_3. Elementary expressions for the phonon and phason displacements, strains, stresses, electric potential, electric fields and electric displacements induced by the moving screw dislocation are then arrived at by employing the obtained general solution. The derived solution is verified by comparison with existing solutions. Also obtained in this part of the investigation is the total energy of the moving screw dislocation. The second part of this investigation is devoted to the study of the interaction of a straight dislocation with a semi-infinite crack in an octagonal quasicrystal. Here the crack penetrates through the solid along the period direction and the dislocation line is parallel to the period direction. We first derive a general solution in terms of four analytic functions for plane strain problem in octagonal quasicrystals by means of differential operator theory and the complex variable method. All the phonon and phason displacements and stresses can be expressed in terms of the four analytic functions. Then we derive the exact solution for a straight dislocation near a semi-infinite crack in an octagonal quasicrystal, and also present the phonon and phason stress intensity factors induced by the straight dislocation and remote loads.

  12. 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)

  13. 1D finite volume model of unsteady flow over mobile bed

    NASA Astrophysics Data System (ADS)

    Zhang, Shiyan; Duan, Jennifer G.

    2011-07-01

    SummaryA one dimensional (1D) finite volume method (FVM) model was developed for simulating unsteady flow, such as dam break flow, and flood routing over mobile alluvium. The governing equation is the modified 1D shallow water equation and the Exner equation that take both bed load and suspended load transport into account. The non-equilibrium sediment transport algorithm was adopted in the model, and the van Rijn method was employed to calculate the bed-load transport rate and the concentration of suspended sediment at the reference level. Flux terms in the governing equations were discretised using the upwind flux scheme, Harten et al. (1983) (HLL) and HLLC schemes, Roe's scheme and the Weighted Average Flux (WAF) schemes with the Double Minmod and Minmod flux limiters. The model was tested under a fixed bed condition to evaluate the performance of several different numerical schemes and then applied to an experimental case of dam break flow over a mobile bed and a flood event in the Rillito River, Tucson, Arizona. For dam break flow over movable bed, all tested schemes were proved to be capable of reasonably simulating water surface profiles, but failed to accurately capture the hydraulic jump. The WAF schemes produced slight spurious oscillations at the water surface and bed profiles and over-estimated the scour depth. When applying the model to the Rillito River, the simulated results generally agreed well with the field measurements of flow discharges and bed elevation changes. Modeling results of bed elevation changes were sensitive to the suspended load recovery coefficient and the bed load adaptation length, which require further theoretical and experimental investigations.

  14. 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.

  15. 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.

  16. The reaction of O(1 D) with H2O and the reaction of OH with C3H6

    NASA Technical Reports Server (NTRS)

    Simonaitis, R.; Heicklen, J.

    1972-01-01

    The N2O was photolyzed at 2139 A to produce O(1 D) atoms in the presence of H2O and CO. The O(1 D) atoms react with H2O to produce HO radicals, as measured by CO2 production from the reaction of OH with CO. The relative rate constant for O(1 D) removal by H2O compared to that by N2O is 2.1. In the presence of C3H6, the OH can be removed by reaction with either CO or C3H6.

  17. Exploiting the CD1d-iNKT cell axis for potentiation of DC-based cancer vaccines.

    PubMed

    Lameris, Roeland; Schneiders, Famke L; de Gruijl, Tanja D; van der Vliet, Hans J

    2014-01-01

    Invariant natural killer T cells (iNKT) and dendritic cells (DC) play a central role in tumor immunity through downstream activation of immune effector cells by pro-inflammatory cytokines. Evidence is accumulating that the CD1d-iNKT cell axis can be effectively used to potentiate DC-based cancer vaccines. Here, we provide a detailed methodology for the generation of (CD1d-expressing) monocyte-derived DC (moDC) and their subsequent loading with the iNKT cell agonist α-galactosylceramide (α-GalCer) or their direct ligation by agonistic anti-CD1d monoclonal antibodies.

  18. F2-region atmospheric gravity waves due to high-power HF heating and subauroral polarization streams

    NASA Astrophysics Data System (ADS)

    Mishin, E.; Sutton, E.; Milikh, G.; Galkin, I.; Roth, C.; Förster, M.

    2012-06-01

    We report the first evidence of atmospheric gravity waves (AGWs) generated in the F2 region by high-power HF heating and subauroral polarization streams. Data come from the CHAMP and GRACE spacecraft overflying the High-frequency Active Auroral Research Program (HAARP) heating facility. These observations facilitate a new method of studying the ionosphere-thermosphere coupling in a controlled fashion by using various HF-heating regimes. They also reveal the subauroral F2 region to be a significant source of substorm AGWs, in addition to the well-known auroral E region.

  19. Ultracold collisions of O(1D) and H2: The effects of H2 vibrational excitation on the production of vibrationally and rotationally excited OH

    NASA Astrophysics Data System (ADS)

    Pradhan, G. B.; Balakrishnan, N.; Kendrick, Brian K.

    2013-04-01

    A quantum dynamics study of the O(1D) + H2(v = 0 - 2, j = 0) system has been carried out using the potential energy surfaces of Dobbyn and Knowles [Mol. Phys. 91, 1107 (1997), 10.1080/002689797170842]. A time-independent quantum mechanical method based on hyperspherical coordinates is adopted for the dynamics calculations. Energy dependent cross section, probability, and rate coefficients are computed for the elastic, inelastic, and reactive channels over collision energies ranging from the ultracold to thermal regimes and for total angular momentum quantum number J = 0. The effect of initial vibrational excitation of the H2 molecule on vibrational and rotational populations of the OH product is investigated as a function of the collision energy. Comparison of results for vibrational levels v = 0 - 2 of H2 demonstrates that the vibrational excitation of H2 and its non-reactive relaxation pathway play a minor role in the overall collisional outcome of O(1D) and H2. It is also found that while the state-resolved product vibrational distributions are sensitive to the initial collision energy and H2 vibrational level, the product rotational distribution depicts an inverted population that is largely insensitive to initial conditions. Rate coefficients evaluated using a J-shifting approximation show reasonable agreement with available theoretical and experimental results suggesting that the J-shifting approximation may be used to evaluate the rate coefficients for O(1D) + H2 reaction.

  20. Novel mutations in DNAJB6 gene cause a very severe early-onset limb-girdle muscular dystrophy 1D disease.

    PubMed

    Palmio, Johanna; Jonson, Per Harald; Evilä, Anni; Auranen, Mari; Straub, Volker; Bushby, Kate; Sarkozy, Anna; Kiuru-Enari, Sari; Sandell, Satu; Pihko, Helena; Hackman, Peter; Udd, Bjarne

    2015-11-01

    DNAJB6 is the causative gene for limb-girdle muscular dystrophy 1D (LGMD1D). Four different coding missense mutations, p.F89I, p.F93I, p.F93L, and p.P96R, have been reported in families from Europe, North America and Asia. The previously known mutations cause mainly adult-onset proximal muscle weakness with moderate progression and without respiratory involvement. A Finnish family and a British patient have been studied extensively due to a severe muscular dystrophy. The patients had childhood-onset LGMD, loss of ambulation in early adulthood and respiratory involvement; one patient died of respiratory failure aged 32. Two novel mutations, c.271T > A (p.F91I) and c.271T > C (p.F91L), in DNAJB6 were identified by whole exome sequencing as a cause of this severe form of LGMD1D. The results were confirmed by Sanger sequencing. The anti-aggregation effect of the mutant DNAJB6 was investigated in a filter-trap based system using transient transfection of mammalian cell lines and polyQ-huntingtin as a model for an aggregation-prone protein. Both novel mutant proteins show a significant loss of ability to prevent aggregation.