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Sample records for 1-dx 1-d diffusion

  1. 1-D EQUILIBRIUM DISCRETE DIFFUSION MONTE CARLO

    SciTech Connect

    T. EVANS; ET AL

    2000-08-01

    We present a new hybrid Monte Carlo method for 1-D equilibrium diffusion problems in which the radiation field coexists with matter in local thermodynamic equilibrium. This method, the Equilibrium Discrete Diffusion Monte Carlo (EqDDMC) method, combines Monte Carlo particles with spatially discrete diffusion solutions. We verify the EqDDMC method with computational results from three slab problems. The EqDDMC method represents an incremental step toward applying this hybrid methodology to non-equilibrium diffusion, where it could be simultaneously coupled to Monte Carlo transport.

  2. 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.

  3. Quantum Diffusion on Molecular Tubes: Universal Scaling of the 1D to 2D Transition

    NASA Astrophysics Data System (ADS)

    Chuang, Chern; Lee, Chee Kong; Moix, Jeremy M.; Knoester, Jasper; Cao, Jianshu

    2016-05-01

    The transport properties of disordered systems are known to depend critically on dimensionality. We study the diffusion coefficient of a quantum particle confined to a lattice on the surface of a tube, where it scales between the 1D and 2D limits. It is found that the scaling relation is universal and independent of the temperature, disorder, and noise parameters, and the essential order parameter is the ratio between the localization length in 2D and the circumference of the tube. Phenomenological and quantitative expressions for transport properties as functions of disorder and noise are obtained and applied to real systems: In the natural chlorosomes found in light-harvesting bacteria the exciton transfer dynamics is predicted to be in the 2D limit, whereas a family of synthetic molecular aggregates is found to be in the homogeneous limit and is independent of dimensionality.

  4. Quantum Diffusion on Molecular Tubes: Universal Scaling of the 1D to 2D Transition.

    PubMed

    Chuang, Chern; Lee, Chee Kong; Moix, Jeremy M; Knoester, Jasper; Cao, Jianshu

    2016-05-13

    The transport properties of disordered systems are known to depend critically on dimensionality. We study the diffusion coefficient of a quantum particle confined to a lattice on the surface of a tube, where it scales between the 1D and 2D limits. It is found that the scaling relation is universal and independent of the temperature, disorder, and noise parameters, and the essential order parameter is the ratio between the localization length in 2D and the circumference of the tube. Phenomenological and quantitative expressions for transport properties as functions of disorder and noise are obtained and applied to real systems: In the natural chlorosomes found in light-harvesting bacteria the exciton transfer dynamics is predicted to be in the 2D limit, whereas a family of synthetic molecular aggregates is found to be in the homogeneous limit and is independent of dimensionality. PMID:27232033

  5. Retroviral intasomes search for a target DNA by 1D diffusion which rarely results in integration.

    PubMed

    Jones, Nathan D; Lopez, Miguel A; Hanne, Jeungphill; Peake, Mitchell B; Lee, Jong-Bong; Fishel, Richard; Yoder, Kristine E

    2016-01-01

    Retroviruses must integrate their linear viral cDNA into the host genome for a productive infection. Integration is catalysed by the retrovirus-encoded integrase (IN), which forms a tetramer or octamer complex with the viral cDNA long terminal repeat (LTR) ends termed an intasome. IN removes two 3'-nucleotides from both LTR ends and catalyses strand transfer of the recessed 3'-hydroxyls into the target DNA separated by 4-6 bp. Host DNA repair restores the resulting 5'-Flap and single-stranded DNA (ssDNA) gap. Here we have used multiple single molecule imaging tools to determine that the prototype foamy virus (PFV) retroviral intasome searches for an integration site by one-dimensional (1D) rotation-coupled diffusion along DNA. Once a target site is identified, the time between PFV strand transfer events is 470 ms. The majority of PFV intasome search events were non-productive. These observations identify new dynamic IN functions and suggest that target site-selection limits retroviral integration. PMID:27108531

  6. Retroviral intasomes search for a target DNA by 1D diffusion which rarely results in integration

    PubMed Central

    Jones, Nathan D.; Lopez Jr, Miguel A.; Hanne, Jeungphill; Peake, Mitchell B.; Lee, Jong-Bong; Fishel, Richard; Yoder, Kristine E.

    2016-01-01

    Retroviruses must integrate their linear viral cDNA into the host genome for a productive infection. Integration is catalysed by the retrovirus-encoded integrase (IN), which forms a tetramer or octamer complex with the viral cDNA long terminal repeat (LTR) ends termed an intasome. IN removes two 3′-nucleotides from both LTR ends and catalyses strand transfer of the recessed 3′-hydroxyls into the target DNA separated by 4–6 bp. Host DNA repair restores the resulting 5′-Flap and single-stranded DNA (ssDNA) gap. Here we have used multiple single molecule imaging tools to determine that the prototype foamy virus (PFV) retroviral intasome searches for an integration site by one-dimensional (1D) rotation-coupled diffusion along DNA. Once a target site is identified, the time between PFV strand transfer events is 470 ms. The majority of PFV intasome search events were non-productive. These observations identify new dynamic IN functions and suggest that target site-selection limits retroviral integration. PMID:27108531

  7. Dynamic MEMS-based linear (1D) diffusers for laser beam homogenizing and beam shaping

    NASA Astrophysics Data System (ADS)

    Masson, J.; Bich, A.; Noell, W.; Voelkel, R.; Weible, K. J.; De Rooij, N. F.

    2009-08-01

    We present a dynamic laser beam shaper based on MEMS technology. We show a prototype of a dynamic diffuser made of single crystal silicon. A linearly deformable silicon micromembrane is used to diffuse a laser beam in one dimension. Resonance frequencies of the membrane can range from 1 kHz to 100 kHz. Diffusing angle can be tuned by adjusting the driving voltage. We measured a diffusing angle of 0.16° for an actuation voltage of 20 V.

  8. Data Assimilation Using a Variational Method for a 1D Radiation Belt Diffusion Model

    NASA Astrophysics Data System (ADS)

    Marchand, R.; Degeling, A. W.; O'Donnell, S.; Rankin, R.; Kabin, K.

    2009-12-01

    A variational data assimilation algorithm has been developed to incorporate electron flux time-series data from satellites into a simple one dimensional diffusion model for the radial transport of radiation belt electrons. The model developed assumes a power law scaling for the radial diffusion coefficient with L shell. The effectiveness of this method is investigated by means of a series of identical twin numerical experiments. This involves using the diffusion model to produce synthetic observations along various satellite trajectories. These observations are in turn used to estimate time-dependent parameters input to the diffusion model, which are compared against the values initially used. The data assimilation algorithm considers the time dependent source located at the outer boundary as a function to be determined. Using synthetic satellite electron flux observations, the algorithm computes a source function that, when used as an input to the diffusion model, most closely reproduces the synthetic observations in a least-squares sense. Observational errors are taken into account, and an estimate of the uncertainty in the output source function is also produced. This uncertainty is found to consistently reflect the quality of the source function estimation during identical twin numerical experiments. Initial tests indicate that the quality of the outer boundary source estimation is strongly dependent on the satellite location, indicating that the outer boundary source estimation becomes poor as information relating to the outer boundary contained in the observations is reduced. The potential of using this data assimilation method to estimate one or more parameters that determine the radial diffusion coefficient, and the possibility of determining whether physical processes affecting the observations are missing in the dynamical model will be discussed.

  9. Efficient Conservative Numerical Schemes for 1D Nonlinear Spherical Diffusion Equations with Applications in Battery Modeling

    SciTech Connect

    Zeng, Y; Albertus, P; Klein, R; Chaturvedi, N; Kojic, A; Bazant, MZ; Christensen, J

    2013-06-07

    Mathematical models of batteries which make use of the intercalation of a species into a solid phase need to solve the corresponding mass transfer problem. Because solving this equation can significantly add to the computational cost of a model, various methods have been devised to reduce the computational time. In this paper we focus on a comparison of the formulation, accuracy, and order of the accuracy for two numerical methods of solving the spherical diffusion problem with a constant or non-constant diffusion coefficient: the finite volume method and the control volume method. Both methods provide perfect mass conservation and second order accuracy in mesh spacing, but the control volume method provides the surface concentration directly, has a higher accuracy for a given numbers of mesh points and can also be easily extended to variable mesh spacing. Variable mesh spacing can significantly reduce the number of points that are required to achieve a given degree of accuracy in the surface concentration (which is typically coupled to the other battery equations) by locating more points where the concentration gradients are highest. (C) 2013 The Electrochemical Society. All rights reserved.

  10. A New 2D-Transport, 1D-Diffusion Approximation of the Boltzmann Transport equation

    SciTech Connect

    Larsen, Edward

    2013-06-17

    The work performed in this project consisted of the derivation, implementation, and testing of a new, computationally advantageous approximation to the 3D Boltz- mann transport equation. The solution of the Boltzmann equation is the neutron flux in nuclear reactor cores and shields, but solving this equation is difficult and costly. The new “2D/1D” approximation takes advantage of a special geometric feature of typical 3D reactors to approximate the neutron transport physics in a specific (ax- ial) direction, but not in the other two (radial) directions. The resulting equation is much less expensive to solve computationally, and its solutions are expected to be sufficiently accurate for many practical problems. In this project we formulated the new equation, discretized it using standard methods, developed a stable itera- tion scheme for solving the equation, implemented the new numerical scheme in the MPACT code, and tested the method on several realistic problems. All the hoped- for features of this new approximation were seen. For large, difficult problems, the resulting 2D/1D solution is highly accurate, and is calculated about 100 times faster than a 3D discrete ordinates simulation.

  11. Impurity driven diffusion and destruction of solitons in quasi-1D Bose-Einstein condensates

    NASA Astrophysics Data System (ADS)

    Aycock, Lauren; Hurst, Hilary; Lu, Hsin-I.; Genkina, Dina; Spielman, Ian

    2016-05-01

    Current experimental research on solitons focuses on their collisions with each other and how dimensionality influences their stability and decay. Here, we investigate the effect of evenly distributed impurity atoms on soliton dynamics. We launch lone, long-lived solitons in highly elongated 87 Rb Bose-Einstein condensates (BECs) by phase imprinting and observe oscillations stable over many seconds. We compare these long-lived solitons to those launched in BECs containing a few percent of impurity-the same atomic species in a different Zeeman sublevel-controllably introduced just before evaporation to degeneracy. These impurities - evenly distributed throughout the condensate - dramatically decrease the soliton lifetime and enhance Brownian-like diffusion in the soliton's trajectory.

  12. Role of N-terminal domain of HMW 1Dx5 in the functional and structural properties of wheat dough.

    PubMed

    Wang, Jing Jing; Liu, Guang; Huang, Yan-Bo; Zeng, Qiao-Hui; Song, Guo-Sheng; Hou, Yi; Li, Lin; Hu, Song-Qing

    2016-12-15

    Effects of N-terminal domain of high molecular weight glutenin subunit (HMW-GS) 1Dx5 (1Dx5-N) on functional and structural properties of wheat dough were determined by farinographic and rheological analysis, size exclusion chromatography, non-reducing/reducing SDS-PAGE, total free sulfhydryl determination, scanning electron microscopy and Fourier transform infrared spectroscopy. Results showed that 1Dx5-N improved the quality of dough with the increased water absorption, dough stability time, elastic and viscous modulus, and the decreased degree of softening, loss tangent. These improvements could be attributed to the formation of the macro-molecular weight aggregates and massive protein networks, which were favored by 1Dx5-N through disulfide bonds and hydrophobic interactions. Additionally, 1Dx5-N drove the transition of α-helix and random coil conformations to β-sheet and β-turn conformations, further demonstrating the formation of HMW-GS polymers and the enhancement of dough strength. Moreover, all the positive effects of 1Dx5-N were reinforced by edible salt NaCl. PMID:27451235

  13. Haplotype variation of Glu-D1 locus and the origin of Glu-D1d allele conferring superior end-use qualities in common wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In common wheat (Triticum aestivum, AABBDD), the Glu-D1 locus possesses multiple alleles, with Glu-D1a (coding for 1Dx2 and 1Dy12 subunits) and Glu-D1d (encoding 1Dx5 and 1Dy10 subunits) being intensively used in the genetic improvement of end-use qualities. Here, we studied the molecular variatio...

  14. Probing the pseudo-1-D ion diffusion in lithium titanium niobate anode for Li-ion battery.

    PubMed

    Das, Suman; Dutta, Dipak; Araujo, Rafael B; Chakraborty, Sudip; Ahuja, Rajeev; Bhattacharyya, Aninda J

    2016-08-10

    Comprehensive understanding of the charge transport mechanism in the intrinsic structure of an electrode material is essential in accounting for its electrochemical performance. We present here systematic experimental and theoretical investigations of Li(+)-ion diffusion in a novel layered material, viz. lithium titanium niobate. Lithium titanium niobate (exact composition Li0.55K0.45TiNbO5·1.06H2O) is obtained from sol-gel synthesized potassium titanium niobate (KTiNbO5) by an ion-exchange method. The Li(+)-ions are inserted and de-inserted preferentially into the galleries between the octahedral layers formed by edge and corner sharing TiO6 and NbO6 octahedral units and the effective chemical diffusion coefficient, is estimated to be 3.8 × 10(-11) cm(2) s(-1) using the galvanostatic intermittent titration technique (GITT). Calculations based on density functional theory (DFT) strongly confirm the anisotropic Li(+)-ion diffusion in the interlayer galleries and that Li(+)-ions predominantly diffuse along the crystallographic b-direction. The preferential Li(+)-ion diffusion along the b-direction is assisted by line-defects, which are observed to be higher in concentration along the b-direction compared to the a- and c-directions, as revealed by high resolution electron microscopy. The Li-Ti niobate can be cycled to low voltages (≈0.2 V) and show stable and satisfactory battery performance over 100 cycles. Due to the possibility of cycling to low voltages, cyclic voltammetry and X-ray photoelectron spectroscopy convincingly reveal the reversibility of Ti(3+) ↔ Ti(2+) along with Ti(4+) ↔ Ti(3+) and Nb(5+) ↔ Nb(4+). PMID:27459636

  15. A belt transect setting strategy for mark-recapture experiments to evaluate the 1D diffusion coefficient of beached litter in the cross-shore direction.

    PubMed

    Hinata, Hirofumi; Kataoka, Tomoya

    2016-08-15

    We propose a belt transect setting strategy for mark-recapture experiments (MREs) to evaluate the time-independent 1D diffusion coefficient (〈Dp0〉) of marine litter in the cross-shore direction that determines the backwashing flux of the litter, based on two-year MREs for plastic floats (PFs) on Wadahama Beach, Nii-jima Island, Japan. When the alongshore width of the belt transect (Lt) was of the order of, or longer than, the length scale of wave-induced nearshore current circulation (Lc), the PFs were rarely transported alongshore across the selected transects prior to being backwashed offshore. Thus, the transect residence time became longer and showed a much weaker dependence on the transect position, in contrast to when Lt was even shorter than Lc. We therefore obtained the diffusion coefficients close to the value of (〈Dp0〉) when we set Lt to the order of, or longer than, Lc. PMID:27263978

  16. Basin infilling of a schematic 1D estuary using two different approaches: an aggregate diffusive type model and a processed based model.

    NASA Astrophysics Data System (ADS)

    Laginha Silva, Patricia; Martins, Flávio A.; Boski, Tomász; Sampath, Dissanayake M. R.

    2010-05-01

    processes. In this viewpoint the system is broken down into its fundamental components and processes and the model is build up by selecting the important processes regardless of its time and space scale. This viewpoint was only possible to pursue in the recent years due to improvement in system knowledge and computer power (Paola, 2000). The primary aim of this paper is to demonstrate that it is possible to simulate the evolution of the sediment river bed, traditionally studied with synthetic models, with a process-based hydrodynamic, sediment transport and morphodynamic model, solving explicitly the mass and momentum conservation equations. With this objective, a comparison between two mathematical models for alluvial rivers is made to simulate the evolution of the sediment river bed of a conceptual 1D embayment for periods in the order of a thousand years: the traditional synthetic basin infilling aggregate diffusive type model based on the diffusion equation (Paola, 2000), used in the "synthesist" viewpoint and the process-based model MOHID (Miranda et al., 2000). The simulation of the sediment river bed evolution achieved by the process-based model MOHID is very similar to those obtained by the diffusive type model, but more complete due to the complexity of the process-based model. In the MOHID results it is possible to observe a more comprehensive and realistic results because this type of model include processes that is impossible to a synthetic model to describe. At last the combined effect of tide, sea level rise and river discharges was investigated in the process based model. These effects cannot be simulated using the diffusive type model. The results demonstrate the feasibility of using process based models to perform studies in scales of 10000 years. This is an advance relative to the use of synthetic models, enabling the use of variable forcing. REFERENCES • Briggs, L.I. and Pollack, H.N., 1967. Digital model of evaporate sedimentation. Science, 155, 453

  17. On the potential for CO2 mineral storage in continental flood basalts - PHREEQC batch- and 1D diffusion-reaction simulations.

    PubMed

    Van Pham, Thi Hai; Aagaard, Per; Hellevang, Helge

    2012-01-01

    Continental flood basalts (CFB) are considered as potential CO2 storage sites because of their high reactivity and abundant divalent metal ions that can potentially trap carbon for geological timescales. Moreover, laterally extensive CFB are found in many place in the world within reasonable distances from major CO2 point emission sources.Based on the mineral and glass composition of the Columbia River Basalt (CRB) we estimated the potential of CFB to store CO2 in secondary carbonates. We simulated the system using kinetic dependent dissolution of primary basalt-minerals (pyroxene, feldspar and glass) and the local equilibrium assumption for secondary phases (weathering products). The simulations were divided into closed-system batch simulations at a constant CO2 pressure of 100 bar with sensitivity studies of temperature and reactive surface area, an evaluation of the reactivity of H2O in scCO2, and finally 1D reactive diffusion simulations giving reactivity at CO2 pressures varying from 0 to 100 bar.Although the uncertainty in reactive surface area and corresponding reaction rates are large, we have estimated the potential for CO2 mineral storage and identified factors that control the maximum extent of carbonation. The simulations showed that formation of carbonates from basalt at 40 C may be limited to the formation of siderite and possibly FeMg carbonates. Calcium was largely consumed by zeolite and oxide instead of forming carbonates. At higher temperatures (60 - 100 C), magnesite is suggested to form together with siderite and ankerite. The maximum potential of CO2 stored as solid carbonates, if CO2 is supplied to the reactions unlimited, is shown to depend on the availability of pore space as the hydration and carbonation reactions increase the solid volume and clog the pore space. For systems such as in the scCO2 phase with limited amount of water, the total carbonation potential is limited by the amount of water present for hydration of basalt

  18. Explicit lower bounds for the cost of fast controls for some 1-D parabolic or dispersive equations, and a new lower bound concerning the uniform controllability of the 1-D transport-diffusion equation

    NASA Astrophysics Data System (ADS)

    Lissy, Pierre

    2015-11-01

    In this paper, we prove explicit lower bounds for the cost of fast boundary controls for a class of linear equations of parabolic or dispersive type involving the spectral fractional Laplace operator. We notably deduce the following striking result: in the case of the heat equation controlled on the boundary, Miller's conjecture formulated in Miller (2004) [16] is not verified. Moreover, we also give a new lower bound for the minimal time needed to ensure the uniform controllability of the one-dimensional convection-diffusion equation with negative speed controlled on the left boundary, proving that the conjecture formulated in Coron and Guerrero (2005) [2] concerning this problem is also not verified at least for negative speeds. The proof is based on complex analysis, and more precisely on a representation formula for entire functions of exponential type, and is quite related to the moment method.

  19. Assessing the accuracy of 1-D analytical heat tracing for estimating near-surface sediment thermal diffusivity and water flux under transient conditions

    NASA Astrophysics Data System (ADS)

    Rau, Gabriel C.; Cuthbert, Mark O.; McCallum, Andrew M.; Halloran, Landon J. S.; Andersen, Martin S.

    2015-08-01

    Amplitude decay and phase delay of oscillating temperature records measured at two vertical locations in near-surface sediments can be used to infer water fluxes, thermal diffusivity, and sediment scour/deposition. While methods that rely on the harmonics-based analytical heat transport solution assume a steady state water flux, many applications have reported transient fluxes but ignored the possible violation of this assumption in the method. Here we use natural heat tracing as an example to investigate the extent to which changes in the water flux, and associated temperature signal nonstationarity, can be separated from other influences. We systematically scrutinize the assumption of steady state flow in analytical heat tracing and test the capabilities of the method to detect the timing and magnitude of flux transients. A numerical model was used to synthesize the temperature response to different step and ramp changes in advective thermal velocity magnitude and direction for both a single-frequency and multifrequency temperature boundary. Time-variable temperature amplitude and phase information were extracted from the model output with different signal-processing methods. We show that a worst-case transient flux induces a temperature nonstationarity, the duration of which is less than 1 cycle for realistic sediment thermal diffusivities between 0.02 and 0.13 m2/d. However, common signal-processing methods introduce erroneous temporal spreading of advective thermal velocities and significant anomalies in thermal diffusivities or sensor spacing, which is used as an analogue for streambed scour/deposition. The most time-variant spectral filter can introduce errors of up to 57% in velocity and 33% in thermal diffusivity values with artifacts spanning ±2 days around the occurrence of rapid changes in flux. Further, our results show that analytical heat tracing is unable to accurately resolve highly time-variant fluxes and thermal diffusivities and does not allow

  20. Study of wheat high molecular weight 1Dx5 subunit by (13)C and (1)H solid-state NMR. II. Roles of nonrepetitive terminal domains and length of repetitive domain.

    PubMed

    Alberti, Enrica; Gilbert, Simon M; Tatham, Arthur S; Shewry, Peter R; Naito, Akira; Okuda, Kanna; Saitô, Hazime; Gil, Ana M

    2002-10-15

    This work follows a previous article that addressed the role of disulfide bonds in the behavior of the 1Dx5 subunit upon hydration. Here the roles of nonrepetitive terminal domains present and the length of the central repetitive domain in the hydration of 1Dx5 are investigated. This was achieved by comparing the hydration behavior of suitable model samples determined by (13)C- and (1)H-NMR: an alkylated 1Dx5 subunit (alk1Dx5), a recombinant 58-kDa peptide corresponding to the central repetitive domain of 1Dx5 (i.e., lacking the terminal domains), and two synthetic peptides (with 6 and 21 amino acid residues) based on the consensus repeat motifs of the central domain. The (13)C cross-polarization and magic angle spinning (MAS) experiments recorded as a function of hydration gave information about the protein or peptide fractions resisting plasticization. Conversely, (13)C single pulse excitation and (1)H-MAS gave information on the more plasticized segments. The results are consistent with the previous proposal of a hydrated network held by hydrogen-bonded glutamines and possibly hydrophobic interactions. The nonrepetitive terminal domains were found to induce water insolubility and a generally higher network hindrance. Shorter chain lengths were shown to increase plasticization and water solubility. However, at low water contents, the 21-mer peptide was characterized by higher hindrance in the megahertz and kilohertz frequency ranges compared to the longer peptide; and a tendency for a few hydrogen-bonded glutamines and hydrophobic residues to remain relatively hindered was still observed, as for the protein and large peptide. It is suggested that this ability is strongly dependent on the peptide primary structure. PMID:12209466

  1. Vought F4U-1D Corsair

    NASA Technical Reports Server (NTRS)

    1945-01-01

    Vought F4U-1D Corsair: In February and March of 1945 this Corsair was examined in the NACA's 30 x 60 Full Scale Tunnel at Langley Field. The F4U-1D has rockets mounted on its wings for this test. After installation and during testing, the wings would be lowered to their flight position.

  2. 1D ferrimagnetism in homometallic chains

    NASA Astrophysics Data System (ADS)

    Coronado, E.; Gómez-García, C. J.; Borrás-Almenar, J. J.

    1990-05-01

    The magnetic properties of the cobalt zigzag chain Co(bpy)(NCS)2 (bpy=2,2'-bipyridine) are discussed on the basis of an Ising-chain model that takes into account alternating Landé factors. It is emphasized, for the first time, that a homometallic chain containing only one type of site can give rise to a 1D ferrimagneticlike behavior.

  3. DESIGN PACKAGE 1D SYSTEM SAFETY ANALYSIS

    SciTech Connect

    L.R. Eisler

    1995-02-02

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

  4. Preparation of 1D nanostructures using biomolecules

    NASA Astrophysics Data System (ADS)

    Pruneanu, Stela; Olenic, Liliana; Barbu Tudoran, Lucian; Kacso, Irina; Farha Al-Said, Said A.; Hassanien, Reda; Houlton, Andrew; Horrocks, Benjamin R.

    2009-08-01

    In this paper we have shown that one-dimensional (1D) particle arrays can be obtained using biomolecules, like DNA or amino-acids. Nano-arrays of silver and gold were prepared in a single-step synthesis, by exploiting the binding abilities of λ-DNA and L-Arginine. The morphology and optical properties of these nanostructures were investigated using AFM, TEM and UV-Vis absorption spectroscopy.

  5. Temperature dependence of soliton diffusion in trans-polyacetylene

    SciTech Connect

    Tang, J.; Norris, J.R.; Isoya, J.

    1997-07-01

    The temperature dependence of 1-D diffusion rate of solitons in transpolyacetylene is determined by time-domain analysis of ESR measurements. The diffusion rate appears to obey a simple power law. Monte Carlo simulation of 1-D diffusion process in impure chains indicates that overall diffusion can be much slower than that without traps.

  6. Coalescence phenomena in 1D silver nanostructures

    NASA Astrophysics Data System (ADS)

    Gutiérrez-Wing, C.; Pérez-Alvarez, M.; Mondragón-Galicia, G.; Arenas-Alatorre, J.; Gutiérrez-Wing, M. T.; Henk, M. C.; Negulescu, I. I.; Rusch, K. A.

    2009-07-01

    Different coalescence processes on 1D silver nanostructures synthesized by a PVP assisted reaction in ethylene glycol at 160 °C were studied experimentally and theoretically. Analysis by TEM and HRTEM shows different defects found on the body of these materials, suggesting that they were induced by previous coalescence processes in the synthesis stage. TEM observations showed that irradiation with the electron beam eliminates the boundaries formed near the edges of the structures, suggesting that this process can be carried out by the application of other means of energy (i.e. thermal). These results were also confirmed by theoretical calculations by Monte Carlo simulations using a Sutton-Chen potential. A theoretical study by molecular dynamics simulation of the different coalescence processes on 1D silver nanostructures is presented, showing a surface energy driven sequence followed to form the final coalesced structure. Calculations were made at 1000-1300 K, which is near the melting temperature of silver (1234 K). Based on these results, it is proposed that 1D nanostructures can grow through a secondary mechanism based on coalescence, without losing their dimensionality.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. EXPRESSION ANALYSIS OF GLU-1DX5 TRANSGENIC CORN

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Maize endosperm is one of the most significant agronomic tissues because it is the major component of feed made from maize grain. An important trait of endosperm is therefore its content of essential amino acids. Because the majority of endosperm protein is in the form of seed storage proteins, the...

  12. 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.

  13. 2D/1D approximations to the 3D neutron transport equation. I: Theory

    SciTech Connect

    Kelley, B. W.; Larsen, E. W.

    2013-07-01

    A new class of '2D/1D' approximations is proposed for the 3D linear Boltzmann equation. These approximate equations preserve the exact transport physics in the radial directions x and y and diffusion physics in the axial direction z. Thus, the 2D/1D equations are more accurate approximations of the 3D Boltzmann equation than the conventional 3D diffusion equation. The 2D/1D equations can be systematically discretized, to yield accurate simulation methods for 3D reactor core problems. The resulting solutions will be more accurate than 3D diffusion solutions, and less expensive to generate than standard 3D transport solutions. In this paper, we (i) show that the simplest 2D/1D equation has certain desirable properties, (ii) systematically discretize this equation, and (iii) derive a stable iteration scheme for solving the discrete system of equations. In a companion paper [1], we give numerical results that confirm the theoretical predictions of accuracy and iterative stability. (authors)

  14. 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.

  15. 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.

  16. Understanding 1D Electrostatic Dust Levitation

    NASA Astrophysics Data System (ADS)

    Hartzell, C. M.; Scheeres, D. J.

    2011-12-01

    Electrostatically-dominated dust motion has been hypothesized since the Lunar Horizon Glow was observed by the Surveyor spacecraft. The hypothesized occurence of this phenomenon was naturally extended to asteroids due to their small gravities. Additionally, it has been suggested that the dust ponds observed on Eros by the NEAR mission may be created by electrostatically-dominated dust transport. Previous attempts to numerically model dust motion on the Moon and Eros have been stymied by poorly understood dust launching mechanisms. As a result, the initial velocity and charge of dust particles used in numerical simulations may or may not have any relevance to the actual conditions occurring in situ. It has been seen that properly tuned initial states (velocity and charge) result in dust particles levitating above the surface in both 1D and 2D simulations. Levitation is of interest to planetary scientists since it provides a way to quickly redistribute the surface dust particles over a body. However, there is currently no method to predict whether or not a certain initial state will result in levitation. We have developed a method to provide constraints on the initial states that result in levitation as a function of dust particle size and central body gravity. Additionally, our method can be applied to several models of the plasma sheath. Thus, we limit the guesswork involved in determining which initial conditions result in levitation. We provide a more detailed understanding of levitation phenomena couched in terms of the commonly recognized spring-mass system. This method of understanding dust motion removes the dependency on the launching mechanism, which remains fraught with controversy. Once a feasible dust launching mechanism is identified (be it micrometeoroid bombardment or electrostatic lofting), our method will allow the community to quickly ascertain if dust levitation will occur in situ or if it is simply a numerical artifact. In addition to

  17. 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.

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

    PubMed Central

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

    1992-01-01

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

  19. Brady 1D seismic velocity model ambient noise prelim

    DOE Data Explorer

    Mellors, Robert J.

    2013-10-25

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

  20. On the parameterization of 1D vertical mixing in planetary atmospheres: insights from 2D and 3D simulations

    NASA Astrophysics Data System (ADS)

    Zhang, Xi; Showman, Adam P.

    2015-11-01

    Most of the current atmospheric chemistry models for planets (e.g., Krasnopolsky & Parshev 1981; Yung & Demore 1982; Yung, Allen & Pinto 1984; Lavvas et al. 2008; Zhang et al. 2012) and exoplanets (e.g., Line, Liang & Yung 2010; Moses et al. 2011; Hu & Seager 2014) adopt a one-dimensional (1D) chemical-diffusion approach in the vertical coordinate. Although only a crude approximation, these 1D models have succeeded in explaining the global-averaged vertical profiles of many chemical species in observations. One of the important assumptions of these models is that all chemical species are transported via the same eddy diffusion profile--that is, the assumption is made that the eddy diffusivity is a fundamental property of the dynamics alone, and does not depend on the chemistry. Here we show that, as also noticed in the Earth community (e.g., Holton 1986), this “homogenous eddy diffusion” assumption generally breaks down. We first show analytically why the 1D eddy diffusivity must generally depend both on the horizontal eddy mixing and the chemical lifetime of the species. This implies that the long-lived species and short-lived chemical species will generally exhibit different eddy diffusion profiles, even in a given atmosphere with identical dynamics. Next, we present tracer-transport simulations in a 2D chemical-diffusion-advection model (Shia et al. 1989; Zhang, Shia & Yung 2013) and a 3D general circulation model (MITgcm, e.g., Liu & Showman 2013), for both rapid-rotating planets and tidally-locked exoplanets, to further explore the effect of chemical timescales on the eddy diffusivity. From the 2D and 3D simulation outputs, we derive effective 1D eddy diffusivity profiles for chemical tracers exhibiting a range of chemical timescales. We show that the derived eddy diffusivity can depend strongly on the horizontal eddy mixing and chemistry, although the dependences are more complex than the analytic model predicts. Overall, these results suggest that

  1. 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

  2. Na-ion dynamics in Quasi-1D compound NaV2O4

    NASA Astrophysics Data System (ADS)

    Månsson, M.; Umegaki, I.; Nozaki, H.; Higuchi, Y.; Kawasaki, I.; Watanabe, I.; Sakurai, H.; Sugiyama, J.

    2014-12-01

    We have used the pulsed muon source at ISIS to study high-temperature Na-ion dynamics in the quasi-one-dimensional (Q1D) metallic antiferromagnet NaV2O4. By performing systematic zero-field and longitudinal-field measurements as a function of temperature we clearly distinguish that the hopping rate increases exponentially above Tdiff ≈ 250 K. The data is well fitted to an Arrhenius type equation typical for a diffusion process, showing that the Na-ions starts to be mobile above Tdiff. Such results make this compound very interesting for the tuning of Q1D magnetism using atomic-scale ion-texturing through the periodic potential from ordered Na-vacancies. Further, it also opens the door to possible use of NaV2O4 and related compounds in energy related applications.

  3. Phosphorylation and desensitization of alpha1d-adrenergic receptors.

    PubMed Central

    García-Sáinz, J A; Vázquez-Cuevas, F G; Romero-Avila, M T

    2001-01-01

    In rat-1 fibroblasts stably expressing rat alpha(1d)-adrenoceptors, noradrenaline and PMA markedly decreased alpha(1d)-adrenoceptor function (noradrenaline-elicited increases in calcium in whole cells and [(35)S]guanosine 5'-[gamma-thio]triphosphate binding in membranes), suggesting homologous and heterologous desensitizations. Photoaffinity labelling, Western blotting and immunoprecipitation identified alpha(1d)-adrenoceptors as a broad band of 70-80 kDa. alpha(1d)-Adrenoceptors were phosphorylated in the basal state and noradrenaline and PMA increased it. The effect of noradrenaline was concentration-dependent (EC(50) 75 nM), rapid (maximum at 1 min) and transient. Phorbol ester-induced phosphorylation was concentration-dependent (EC(50) 25 nM), slightly slower (maximum at 5 min) and stable for at least 60 min. Inhibitors of protein kinase C decreased the effect of phorbol esters but not that of noradrenaline. Evidence of cross-talk of alpha(1d)-adrenoceptors with receptors endogenously expressed in rat-1 fibroblasts was given by the ability of endothelin, lysophosphatidic acid and bradykinin to induce alpha(1d)-adrenoceptor phosphorylation. In summary, it is shown for the first time here that alpha(1d)-adrenoceptors are phosphoproteins and that receptor phosphorylation is increased by the natural ligand, noradrenaline, by direct activation of protein kinase C and via cross-talk with other receptors endogenously expressed in rat-1 fibroblasts. Receptor phosphorylation has functional repercussions. PMID:11171057

  4. Severe Hypertriglyceridemia in Glut1D on Ketogenic Diet.

    PubMed

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

    2016-04-01

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

  5. 1D Nanostructures: Controlled Fabrication and Energy Applications

    SciTech Connect

    Hu, Michael Z.

    2013-01-01

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

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

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

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

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

    PubMed

    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. PMID:25088042

  8. 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

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

    NASA Astrophysics Data System (ADS)

    Marley, Peter Mchael

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

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

    NASA Astrophysics Data System (ADS)

    Marley, Peter Mchael

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

  11. 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.

  12. 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.

  13. 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.

  14. Nanodamage and Nanofailure of 1d Zno Nanomaterials and Nanodevices

    NASA Astrophysics Data System (ADS)

    Li, Peifeng; Yang, Ya; Huang, Yunhua; Zhang, Yue

    2012-08-01

    One-dimensional (1D) ZnO nanomaterials include nanowires, nanobelts, and nanorods etc. The extensive applied fields and excellent properties of 1D ZnO nanomaterials can meet the requests of the electronic and electromechanical devices for "smaller, faster and colder", and would be applied in new energy convention, environmental protection, information science and technology, biomedical, security and defense fields. While micro porous, etching pits nanodamage and brittle fracture, dissolving, functional failure nanofailure phenomena of 1D ZnO nanomaterials and nanodevices are observed in some practical working environments like illumination, currents or electric fields, external forces, and some chemical gases or solvents. The more important thing is to discuss the mechanism and reduce or prohibit their generation.

  15. Resonant indirect exchange in 1D semiconductor nanostructures

    NASA Astrophysics Data System (ADS)

    Rozhansky, I. V.; Krainov, I. V.; Averkiev, N. S.; Lähderanta, E.

    2015-06-01

    We consider resonant indirect exchange interaction between magnetic centers in 1D nanostructures. The magnetic centers are assumed to be coupled to the 1D conducting channel by the quantum tunneling which can be of resonant character. The indirect exchange between the centers is mediated by the free carriers of the channel. The two cases of quadratic and linear energy dispersion of the 1D free carriers are considered. The former case is attributed to conventional semiconductor (InGaAs based to be concrete) nanowires or nanowhiskers, while the latter case is associated with carbon nanotubes with magnetic adatoms. We demonstrate that whenever the energy of a bound state at the magnetic center lies within the continuum energy spectra of the delocalized carriers in the channel the indirect exchange is strongly enhanced due to effective tunnel hybridization of the bound states with the continuum.

  16. Probing 1D super-strongly correlated dipolar quantum gases

    NASA Astrophysics Data System (ADS)

    Citro, R.; de Palo, S.; Orignac, E.; Pedri, P.; Chiofalo, M.-L.

    2009-04-01

    One-dimensional (1D) dipolar quantum gases are characterized by a very special condition where super-strong correlations occur to significantly affect the static and dynamical low-energy behavior. This behavior is accurately described by the Luttinger Liquid theory with parameter K < 1. Dipolar Bose gases are routinely studied in laboratory with Chromium atoms. On the other hand, 1D realizations with molecular quantum gases can be at reach of current experimental expertises, allowing to explore such extreme quantum degenerate conditions which are the bottom line for designing technological devices. Aim of the present contribution is to focus on the possible probes expected to signal the reach of Luttinger-Liquid behavior in 1D dipolar gases.

  17. 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.

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

    NASA Astrophysics Data System (ADS)

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

    2013-10-01

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

  19. Evaluation and characterization of high-molecular weight 1D glutenin subunits from Aegilops tauschii in synthetic hexaploid wheats

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The high-molecular weight (HMW) glutenin subunits of bread wheat (Triticum aestivum L.) are major determinants of end-use quality. The objective of this study was to determine the 1Dx and 1Dy HMW subunits present in 44 synthetic hexaploid wheats (SHW) derived by crossing Langdon durum (T. turgidum ...

  20. A 1D wavelet filtering for ultrasound images despeckling

    NASA Astrophysics Data System (ADS)

    Dahdouh, Sonia; Dubois, Mathieu; Frenoux, Emmanuelle; Osorio, Angel

    2010-03-01

    Ultrasound images appearance is characterized by speckle, shadows, signal dropout and low contrast which make them really difficult to process and leads to a very poor signal to noise ratio. Therefore, for main imaging applications, a denoising step is necessary to apply successfully medical imaging algorithms on such images. However, due to speckle statistics, denoising and enhancing edges on these images without inducing additional blurring is a real challenging problem on which usual filters often fail. To deal with such problems, a large number of papers are working on B-mode images considering that the noise is purely multiplicative. Making such an assertion could be misleading, because of internal pre-processing such as log compression which are done in the ultrasound device. To address those questions, we designed a novel filtering method based on 1D Radiofrequency signal. Indeed, since B-mode images are initially composed of 1D signals and since the log compression made by ultrasound devices modifies noise statistics, we decided to filter directly the 1D Radiofrequency signal envelope before log compression and image reconstitution, in order to conserve as much information as possible. A bi-orthogonal wavelet transform is applied to the log transform of each signal and an adaptive 1D split and merge like algorithm is used to denoise wavelet coefficients. Experiments were carried out on synthetic data sets simulated with Field II simulator and results show that our filter outperforms classical speckle filtering methods like Lee, non-linear means or SRAD filters.

  1. Optical properties of LEDs with patterned 1D photonic crystal

    NASA Astrophysics Data System (ADS)

    Hronec, P.; Kuzma, A.; Å kriniarová, J.; Kováč, J.; Benčurová, A.; Haščík, Å.; Nemec, P.

    2015-08-01

    In this paper we focus on the application of the one-dimensional photonic crystal (1D PhC) structures on the top of Al0.295Ga0.705As/GaAs multi-quantum well light emitting diode (MQW LED). 1D PhC structures with periods of 600 nm, 700 nm, 800 nm, and 900 nm were fabricated by the E-Beam Direct Write (EBDW) Lithography. Effect of 1D PhC period on the light extraction enhancement was studied. 1D PhC LED radiation profiles were obtained from Near Surface Light Emission Images (NSLEI). Measurements showed the strongest light extraction enhancement using 800 nm period of PhC. Investigation of PhC LED radiation profiles showed strong light decoupling when light reaches PhC structure. Achieved LEE was from 22.6% for 600 nm PhC LED to 47.0% for 800 nm PhC LED. LED with PhC structure at its surface was simulated by FDTD simulation method under excitation of appropriate launch field.

  2. NEW FEATURES OF HYDRUS-1D, VERSION 3.0

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper briefly summarizes new features in version 3.0 of HYDRUS-1D, released in May 2005, as compared to version 2.1. The new features are a) new approaches to simulate preferential and nonequilibrium water flow and solute transport, b) a new hysteresis module that avoids the effects of pumpin...

  3. 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.

  4. Diffusion of D-alpha-tocopherol (1); carbon dioxide (2)

    NASA Astrophysics Data System (ADS)

    Winkelmann, J.

    This document is part of Subvolume A `Gases in Gases, Liquids and their Mixtures' of Volume 15 `Diffusion in Gases, Liquids and Electrolytes' of Landolt-Börnstein Group IV `Physical Chemistry'. It is part of the chapter of the chapter `Diffusion in Pure Gases' and contains data on diffusion of (1) D-alpha-tocopherol; (2) carbon dioxide

  5. 1D design style implications for mask making and CEBL

    NASA Astrophysics Data System (ADS)

    Smayling, Michael C.

    2013-09-01

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

  6. Holographic diffusers

    NASA Astrophysics Data System (ADS)

    Wadle, Stephen; Wuest, Daniel; Cantalupo, John; Lakes, Roderic S.

    1994-01-01

    Holographic diffusers are prepared using silver halide (Agfa 8E75 and Kodak 649F) and photopolymer (Polaroid DMP 128 and DuPont 600, 705, and 150 series) media. It is possible to control the diffusion angle in three ways: by selection of the properties of the source diffuser, by control of its subtended angle, and by selection of the holographic medium. Several conventional diffusers based on refraction or scattering of light are examined for comparison.

  7. Diffusion MRI

    NASA Astrophysics Data System (ADS)

    Fukuyama, Hidenao

    Recent advances of magnetic resonance imaging have been described, especially stressed on the diffusion sequences. We have recently applied the diffusion sequence to functional brain imaging, and found the appropriate results. In addition to the neurosciences fields, diffusion weighted images have improved the accuracies of clinical diagnosis depending upon magnetic resonance images in stroke as well as inflammations.

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

    PubMed

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

    2015-03-01

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

  9. A Bayesian Algorithm for Reading 1D Barcodes

    PubMed Central

    Tekin, Ender; Coughlan, James

    2010-01-01

    The 1D barcode is a ubiquitous labeling technology, with symbologies such as UPC used to label approximately 99% of all packaged goods in the US. It would be very convenient for consumers to be able to read these barcodes using portable cameras (e.g. mobile phones), but the limited quality and resolution of images taken by these cameras often make it difficult to read the barcodes accurately. We propose a Bayesian framework for reading 1D barcodes that models the shape and appearance of barcodes, allowing for geometric distortions and image noise, and exploiting the redundant information contained in the parity digit. An important feature of our framework is that it doesn’t require that every barcode edge be detected in the image. Experiments on a publicly available dataset of barcode images explore the range of images that are readable, and comparisons with two commercial readers demonstrate the superior performance of our algorithm. PMID:20428491

  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. 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.

  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. Waves in a 1D electrorheological dusty plasma lattice

    NASA Astrophysics Data System (ADS)

    Rosenberg, M.

    2015-08-01

    The behavior of waves in a one-dimensional (1D) dusty plasma lattice where the dust interacts via Yukawa and electric dipole interactions is discussed theoretically. This study is motivated by recent reports on electrorheological dusty plasmas (e.g. Ivlev et al. 2008 Phys. Rev. Lett. 100, 095003) where the dipole interaction arises due to an external uniaxial AC electric field that distorts the Debye sphere surrounding each grain. Application to possible dusty plasma experimental parameters is discussed.

  14. Constructing 3D interaction maps from 1D epigenomes

    PubMed Central

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

    2016-01-01

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

  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. 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.

  17. 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.

  18. 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.

    2016-06-01

    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.

  19. Facilitated diffusion buffers noise in gene expression

    PubMed Central

    Schoech, Armin P.; Zabet, Nicolae Radu

    2014-01-01

    Transcription factors perform facilitated diffusion (3D diffusion in the cytosol and 1D diffusion on the DNA) when binding to their target sites to regulate gene expression. Here, we investigated the influence of this binding mechanism on the noise in gene expression. Our results showed that, for biologically relevant parameters, the binding process can be represented by a two-state Markov model and that the accelerated target finding due to facilitated diffusion leads to a reduction in both the mRNA and the protein noise. PMID:25314467

  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. PMID:25786888

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

    SciTech Connect

    K.R. Maskaly

    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

  2. Spontaneous formation of vorticity staircase and multiple jets in a 1D barotropic model with parameterized eddy mixing

    NASA Astrophysics Data System (ADS)

    Zhu, D.; Nakamura, N.

    2009-12-01

    Spontaneous formation of a vorticity staircase and multiple jets is simulated using a one dimensional barotropic model on a beta-plane with parameterized eddy mixing. The model represents nearly inviscid geostrophic turbulence characterized by a uniform forcing of pseudomomentum, nonuniform dissipation due to mixing, and no frictional damping of the mean flow. The dissipation of pseudomomentum (diffusive flux of vorticity) is modeled with the effective diffusivity parameterization proposed recently by Ferrari and Nikurashin(2009). Rossby wave dynamics and upscale energy cascade are not modeled explicitly but implicit in the parameterization. The parameterized effective diffusivity is a decreasing function of squared vorticity gradient, revealing the active role of (potential) vorticity gradient as a barrier to mixing, consistent with the Rossby elasticity idea. Not only does the parameterized diffusivity agree well with the effective diffusivity of a direct numerical simulation, but it allows the 1D model to reproduce other salient features of the direct simulation, most notably the formation of a welldefined vorticity staircase from a uniform vorticity gradient, through inhomogeneous mixing of vorticity. The staircase formation starts as a small-scale, antidiffusive instability in vorticity gradient that develops when the eddy scale is comparable to the Rhines scale. This spawns numerous gaps (barriers) in diffusivity and corresponding small steps in vorticity, but many of them become unstable and disappear later, until a few stable ones remain. The final number of barriers (vorticity steps) is predictable to a good approximation with a few model parameters.

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

    NASA Astrophysics Data System (ADS)

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

    2011-05-01

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

  4. 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

  5. Coherent thermal conductance of 1-D photonic crystals

    NASA Astrophysics Data System (ADS)

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

    2012-10-01

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

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

    NASA Astrophysics Data System (ADS)

    Huo, Xiaokai; Yong, Wen-An

    2016-07-01

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

  7. 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.

  8. 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.

  9. Phthalocyanine based 1D nanowires for device applications

    NASA Astrophysics Data System (ADS)

    Saini, Rajan; Mahajan, Aman; Bedi, R. K.

    2012-06-01

    1D nanowires (NWs) of Cu (II) 1,4,8,11,15,18,22,25-octabutoxy-29H,31H-Phthalocyanine (CuPc(OBu)8) molecule have been grown on different substrates by cost effective solution processing technique. The density of NWs is found to be strongly dependent on the concentration of solution. The possible formation mechanism of these structures is π-π interaction between phthalocyanine molecules. The improved conductivity of these NWs as compared to spin coated film indicates their potential for molecular device applications.

  10. Validation of 3D/1D Analysis of ICRF Antennas

    NASA Astrophysics Data System (ADS)

    Milanesio, D.; Lancellotti, V.; Kyrytsya, V.; Maggiora, R.; Vecchi, G.; Parisot, A.; Wukitch, S. J.

    2004-11-01

    An innovative tool has been realized for the 3D/1D simulation of Ion Cyclotron Radio Frequency (ICRF), i.e. accounting for antennas in a realistic 3D geometry and with an accurate 1D plasma model. The approach to the problem is based on an integral-equation formulation for the self-consistent evaluation of the current distribution on the conductors. The environment has been subdivided in two coupled region: the plasma region and the vacuum region. The two problems are linked by means of electromagnetic current distribution on the aperture between the two regions. The plasma enters the formalism via a surface impedance matrix for this reason any plasma model can be used. The source term directly models the TEM mode of the coax feeding the antenna and the current in the coax is determined self-consistently, giving the input impedance/admittance of the antenna itself. The suite, called TOPICA, has been used in the design of various ICRF antennas and also for the performance prediction of the ALCATOR C-MOD D and E antenna. An extensive set of comparisons between measured and simulated antenna parameters during ALCATOR C-MOD operation will be presented.

  11. 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.

  12. An evaluation of 1D loss model collections for the off-design performance prediction of automotive turbocharger compressors

    NASA Astrophysics Data System (ADS)

    Harley, P.; Spence, S.; Early, J.; Filsinger, D.; Dietrich, M.

    2013-12-01

    Single-zone modelling is used to assess different collections of impeller 1D loss models. Three collections of loss models have been identified in literature, and the background to each of these collections is discussed. Each collection is evaluated using three modern automotive turbocharger style centrifugal compressors; comparisons of performance for each of the collections are made. An empirical data set taken from standard hot gas stand tests for each turbocharger is used as a baseline for comparison. Compressor range is predicted in this study; impeller diffusion ratio is shown to be a useful method of predicting compressor surge in 1D, and choke is predicted using basic compressible flow theory. The compressor designer can use this as a guide to identify the most compatible collection of losses for turbocharger compressor design applications. The analysis indicates the most appropriate collection for the design of automotive turbocharger centrifugal compressors.

  13. Vaneless diffusers

    NASA Astrophysics Data System (ADS)

    Senoo, Y.

    The influence of vaneless diffusers on flow in centrifugal compressors, particularly on surge, is discussed. A vaneless diffuser can demonstrate stable operation in a wide flow range only if it is installed with a backward leaning blade impeller. The circumferential distortion of flow in the impeller disappears quickly in the vaneless diffuser. The axial distortion of flow at the diffuser inlet does not decay easily. In large specific speed compressors, flow out of the impeller is distorted axially. Pressure recovery of diffusers at distorted inlet flow is considerably improved by half guide vanes. The best height of the vanes is a little 1/2 diffuser width. In small specific speed compressors, flow out of the impeller is not much distorted and pressure recovery can be predicted with one-dimensional flow analysis. Wall friction loss is significant in narrow diffusers. The large pressure drop at a small flow rate can cause the positive gradient of the pressure-flow rate characteristic curve, which may cause surging.

  14. MX chains: 1-D analog of CuO planes

    SciTech Connect

    Gammel, J.T.; Batistic, I.; Bishop, A.R.; Loh, E.Y. Jr.; Marianer, S.

    1989-01-01

    We study a two-band Peierls-Hubbard model for halogen-bridged mixed-valence transition metal linear chain complexes (MX chains). We include electron-electron correlations (both Hubbard and PPP-like expressions) using several techniques including calculations in the zero-hopping limit, exact diagonalization of small systems, mean field approximation, and a Gutzwiller-like Ansatz for quantum phonons. The adiabatic optical absorption and phonon spectra for both photo-excited and doping induced defects (kinks, polarons, bipolarons, and excitons) are discussed. A long period phase which occurs even at commensurate filling for certain parameter values may be related to twinning. The effect of including the electron-phonon in addition to the electron-electron interaction on the polaron/bipolaron (pairing) competition is especially interesting when this class of compounds is viewed as a 1-D analog of high-temperature superconductors. 6 refs., 4 figs.

  15. Quadratic Finite Element Method for 1D Deterministic Transport

    SciTech Connect

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

    2004-01-06

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

  16. Electron Energy Levels in the 1D-2D Transition

    NASA Astrophysics Data System (ADS)

    Pepper, Michael; Sanjeev, Kumar; Thomas, Kalarikad; Creeth, Graham; English, David; Ritchie, David; Griffiths, Jonathan; Farrer, Ian; Jones, Geraint

    Using GaAs-AlGaAs heterostructures we have investigated the behaviour of electron energy levels with relaxation of the potential confining a 2D electron gas into a 1D configuration. In the ballistic regime of transport, when the conductance shows quantized plateaux, different types of behaviour are found according to the spins of interacting levels, whether a magnetic field is applied and lifting of the momentum degeneracy with a source-drain voltage. We have observed both crossing and anti-crossing of levels and have investigated the manner in which they can be mutually converted. In the presence of a magnetic field levels can cross and lock together as the confinement is altered in a way which is characteristic of parallel channels. The overall behaviour is discussed in terms of electron interactions and the wavefunction flexibility allowed by the increasing two dimensionality of the electron distribution as the confinement is weakened. Work supported by UK EPSRC.

  17. Directed enzymatic activation of 1-D DNA tiles.

    PubMed

    Garg, Sudhanshu; Chandran, Harish; Gopalkrishnan, Nikhil; LaBean, Thomas H; Reif, John

    2015-02-24

    The tile assembly model is a Turing universal model of self-assembly where a set of square shaped tiles with programmable sticky sides undergo coordinated self-assembly to form arbitrary shapes, thereby computing arbitrary functions. Activatable tiles are a theoretical extension to the Tile assembly model that enhances its robustness by protecting the sticky sides of tiles until a tile is partially incorporated into a growing assembly. In this article, we experimentally demonstrate a simplified version of the Activatable tile assembly model. In particular, we demonstrate the simultaneous assembly of protected DNA tiles where a set of inert tiles are activated via a DNA polymerase to undergo linear assembly. We then demonstrate stepwise activated assembly where a set of inert tiles are activated sequentially one after another as a result of attachment to a growing 1-D assembly. We hope that these results will pave the way for more sophisticated demonstrations of activated assemblies. PMID:25625898

  18. Magnetic behavior of some 1D Cu chains

    NASA Astrophysics Data System (ADS)

    Willett, Roger D.; Gomez-García, Carlos J.; Ghosh, Ashutosh

    2004-05-01

    The magnetic properties of three 1D copper(II) salts are reported. The compound Cu(14ane)Cu(N 3) 4 contains alternating site chains with weak FM coupling with J/k=0.635 K . Magnetization studies are reported on Cu(TIM)CuCl 4, an alternating site, alternating FM/AFM exchange system with J FM/k=29.7 K and J AFM/k=-8.66 K. (HPy) 2Cu 3Cl 8.2H 2O contains FM chains composed of alternating Cu 2Cl 62- dimers and CuCl 2(H 2O) 2 monomers, with intradimer coupling J 1/k=17.35 K and dimer-monomer coupling J 2/k=1.93 K .

  19. 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.

  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. Robust recognition of 1D barcodes using Hough transform

    NASA Astrophysics Data System (ADS)

    Dwinell, John; Bian, Peng; Bian, Long Xiang

    2012-01-01

    In this paper we present an algorithm for the recognition of 1D barcodes using the Hough transform, which is highly robust regarding the typical degraded image. The algorithm addresses various typical image distortions, such as inhomogeneous illumination, reflections, damaged barcode or blurriness etc. Other problems arise from recognizing low quality printing (low contrast or poor ink receptivity). Traditional approaches are unable to provide a fast solution for handling such complex and mixed noise factors. A multi-level method offers a better approach to best manage competing constraints of complex noise and fast decode. At the lowest level, images are processed in gray scale. At the middle level, the image is transformed into the Hough domain. At the top level, global results, including missing information, is processed within a global context including domain heuristics as well as OCR. The three levels work closely together by passing information up and down between levels.

  2. A 1-D morphodynamic model of postglacial valley incision

    NASA Astrophysics Data System (ADS)

    Tunnicliffe, Jon F.; Church, Michael

    2015-11-01

    Chilliwack River is typical of many Cordilleran valley river systems that have undergone dramatic Holocene degradation of valley fills that built up over the course of Pleistocene glaciation. Downstream controls on base level, mainly blockage of valleys by glaciers, led to aggradation of significant glaciofluvial and glaciolacustrine valley fills and fan deposits, subsequently incised by fluvial action. Models of such large-scale, long-term degradation present a number of important challenges since the evolution of model parameters, such as the rate of bedload transport and grain size characteristics, are governed by the nature of the deposit. Sediment sampling in the Chilliwack Valley reveals a complex sequence of very coarse to fine textural modes. We present a 1-D numerical morphodynamic model for the river-floodplain system tailored to conditions in the valley. The model is adapted to dynamically adjust channel width to optimize sediment transporting capacity and to integrate relict valley fill material as the channel incises through valley deposits. Sensitivity to model parameters is studied using four principal criteria: profile concavity, rate of downstream grain size fining, bed surface sand content, and the timescale to equilibrium. Model results indicate that rates of abrasion and coarsening of the grain size distributions exert the strongest controls on all of the interrelated model performance criteria. While there are a number of difficulties in satisfying all model criteria simultaneously, results indicate that 1-D models of valley bottom sedimentary systems can provide a suitable framework for integrating results from sediment budget studies and chronologies of sediment evacuation established from dating.

  3. Diffusion barriers

    NASA Technical Reports Server (NTRS)

    Nicolet, M. A.

    1983-01-01

    The choice of the metallic film for the contact to a semiconductor device is discussed. One way to try to stabilize a contact is by interposing a thin film of a material that has low diffusivity for the atoms in question. This thin film application is known as a diffusion barrier. Three types of barriers can be distinguished. The stuffed barrier derives its low atomic diffusivity to impurities that concentrate along the extended defects of a polycrystalline layer. Sacrificial barriers exploit the fact that some (elemental) thin films react in a laterally uniform and reproducible fashion. Sacrificial barriers have the advantage that the point of their failure is predictable. Passive barriers are those most closely approximating an ideal barrier. The most-studied case is that of sputtered TiN films. Stuffed barriers may be viewed as passive barriers whose low diffusivity material extends along the defects of the polycrystalline host.

  4. Diffuse radiation

    NASA Technical Reports Server (NTRS)

    1981-01-01

    A diffuse celestial radiation which is isotropic at least on a course scale were measured from the soft X-ray region to about 150 MeV, at which energy the intensity falls below that of the galactic emission for most galactic latitudes. The spectral shape, the intensity, and the established degree of isotropy of this diffuse radiation already place severe constraints on the possible explanations for this radiation. Among the extragalactic theories, the more promising explanations of the isotropic diffuse emission appear to be radiation from exceptional galaxies from matter antimatter annihilation at the boundaries of superclusters of galaxies of matter and antimatter in baryon symmetric big bang models. Other possible sources for extragalactic diffuse gamma radiation are discussed and include normal galaxies, clusters of galaxies, primordial cosmic rays interacting with intergalactic matter, primordial black holes, and cosmic ray leakage from galaxies.

  5. Solves the Multigroup Neutron Diffusion Equation

    Energy Science and Technology Software Center (ESTSC)

    1995-06-23

    GNOMER is a program which solves the multigroup neutron diffusion equation in 1D, 2D and 3D cartesian geometry. The program is designed to calculate the global core power distributions (with thermohydraulic feedbacks), as well as power distribution and homogenized cross sections over a fuel assembly.

  6. Influence of Ag+ interaction on 1D droplet array spacing and the repulsive forces between stimuli-responsive nanoemulsion droplets.

    PubMed

    Mahendran, V; Philip, John

    2014-09-01

    This paper reports results on the effect of interaction of Ag(+) on 1D droplet array spacing and the repulsive forces between stimuli-responsive nanoemulsion droplets, stabilized with an anionic surfactant--sodium dodecyl sulfate--and a diblock polymer--poly(vinyl alcohol)-vinyl acetate. The repulsive interaction is probed by measuring the in-situ equilibrium force-distance in the presence of Ag(+) using the magnetic chaining technique. At a constant static magnetic field, emulsion droplets form 1D array that diffract visible light. A large blue-shift in the diffracted light is observed in the presence of interacting Ag(+) because of the reduction in the interdroplet spacing within the 1D array. The in-situ equilibrium force-distance measurement results show that the onset of repulsions and magnitude of repulsive forces are strongly influenced by the presence of Ag(+) in ppb levels. This suggests that the Ag(+) ions screen the surface charges through the formation of both Stern and diffuse electric double layer and produces a dramatic blue-shift in surfactant-stabilized emulsion, whereas a dramatic conformational change in the adsorbed polymer layer causes a reduction in the 1D array spacing in the diblock polymer stabilized emulsion. The force-distance results are compared with the predictions of electrical double-layer and repulsive steric forces. The droplet array shows an excellent selectivity to Ag(+) due to the strong interaction of Ag(+) with the stabilizing moieties at the oil-water interface. The possible mechanisms of interaction of Ag(+) with surfactant and polymer are discussed. The dramatic decrease in the 1D array spacing in the presence of Ag(+) may find promising practical applications in the development of optical sensors for selective detection of cations with ultrahigh sensitivity. PMID:25105903

  7. 3D/1D Analysis of ICRF Antennas

    NASA Astrophysics Data System (ADS)

    Maggiora, Riccardo; Lancellotti, Vito; Vecchi, Giuseppe

    2003-10-01

    An innovative tool has been realized for the 3D/1D simulation of Ion Cyclotron Radio Frequency (ICRF), i.e. accounting for antennas in a realistic 3D geometry and with an accurate 1D plasma model. The approach to the problem is based on an integral-equation formulation for the self-consistent evaluation of the current distribution on the conductors. The environment has been subdivided in two coupled region: the plasma region and the vacuum region. The two problems are linked by means of a magnetic current (electric field) distribution on the aperture between the two regions. In the vacuum region all the calculations are executed in the spatial domain while in the plasma region an extraction in the spectral domain of some integrals is employed that permits to significantly reduce the integration support and to obtain a high numerical efficiency leading to the practical possibility of using a large number of sub-domain (rectangular or triangular) basis functions on each solid conductor of the system. The plasma enters the formalism of the plasma region via a surface impedance matrix; for this reason any plasma model can be used; at present the FELICE code has been adopted, that affords density and temperature profiles, and FLR effects. The source term directly models the TEM mode of the coax feeding the antenna and the current in the coax is determined self-consistently, giving the input impedance/admittance of the antenna itself. Calculation of field distributions (both magnetic and electric), useful for sheath considerations, is included. This tool has been implemented in a suite, called TOPICA, that is modular and applicable to ICRF antenna structures of arbitrary shape. This new simulation tool can assist during the detailed design phase and for this reason can be considered a "Virtual Prototyping Laboratory" (VPL). The TOPICA suite has been tested against assessed codes and against measurements and data of mock-ups and existing antennas. The VPL is being used in

  8. Spectral functions of 1D Peierls and Mott insulators

    NASA Astrophysics Data System (ADS)

    Voit, Johannes

    1998-03-01

    We construct the spectral function of the Luther-Emery model which describes one-dimensional Peierls and Mott insulators with a spin resp. charge gap, using symmetries and known limits and equivalences to other models. For the Peierls insulator, we find a true singularity with interaction dependent exponents on the gapped spin dispersion and a finite maximum depending on the magnitude of the spin gap, on a charge dispersion shifted by Δ_σ, as well as strong shadow bands with the same functional form as the main bands. For 1D Mott insulators, one or two singularities with universal inverse-square-root singularities are found depending on whether the charge velocity is larger or smaller than the spin velocity. The shadow band has a single singularity on the renormalized charge dispersion. These results could apply to the description of photoemission experiments in systems like K_0.3 Mo O_3, TTF-TCNQ, or Sr Cu O_2.

  9. 1D X-ray Beam Compressing Monochromators

    SciTech Connect

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

    2010-04-06

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

  10. 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.

  11. Graphs on uniform points in [0,1]d

    NASA Astrophysics Data System (ADS)

    Appel, Martin J. B.; Russo, Ralph P.; Yang, King J.

    1995-06-01

    Statistical problems in pattern or structure recognition for a random multidimensional point set may be addressed by variations on the random graph model of Erdos and Renyui. The imposition of graph structure with a variable edge criterion on a large random point set allows a search for signature quantities or behavior under the given distributional hypothesis. The work is motivated by the question of how to make statistical inferences from sensed mine field data. This article describes recent results obtained in the following special cases. On independent random points U1,...,Un distributed uniformly on [0,1]d, a random graph Gn(x) is constructed in which two distinct such points are joined by an edge if the l(infinity )-distance between them is at most some prescribed value 0 = 2.

  12. 1D coordination polymers with polychalcogenides as linkers between metal atoms

    SciTech Connect

    Kysliak, Oleksandr; Beck, Johannes

    2013-07-15

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

  13. Effective-range signatures in quasi-1D matter waves: sound velocity and solitons

    NASA Astrophysics Data System (ADS)

    Sgarlata, F.; Mazzarella, G.; Salasnich, L.

    2015-06-01

    We investigate ultracold and dilute bosonic atoms under strong transverse harmonic confinement using a 1D modified Gross-Pitaevskii equation (1D MGPE), which accounts for the energy dependence of the two-body scattering amplitude within an effective-range expansion. We study sound waves and solitons of the quasi-1D system, comparing the 1D MGPE results with the 1D GPE ones. We find that when the finite-size nature of the interaction is taken into account, the speed of sound and the density profiles of both dark and bright solitons show relevant quantitative changes with respect to predictions given by the standard 1D GPE.

  14. The Existence of Weak &#x1D49F;-Pullback Exponential Attractor for Nonautonomous Dynamical System

    PubMed Central

    Li, Yongjun; Wei, Xiaona; Zhang, Yanhong

    2016-01-01

    First, for a process {U(t, τ)∣t ≥ τ}, we introduce a new concept, called the weak &#x1D49F;-pullback exponential attractor, which is a family of sets {ℳ(t)∣t ≤ T}, for any T ∈ ℝ, satisfying the following: (i) ℳ(t) is compact, (ii) ℳ(t) is positively invariant, that is, U(t, τ)ℳ(τ) ⊂ ℳ(t), and (iii) there exist k, l > 0 such that dist(U(t, τ)B(τ), ℳ(t)) ≤ ke −(t−τ); that is, ℳ(t) pullback exponential attracts B(τ). Then we give a method to obtain the existence of weak &#x1D49F;-pullback exponential attractors for a process. As an application, we obtain the existence of weak &#x1D49F;-pullback exponential attractor for reaction diffusion equation in H 0 1 with exponential growth of the external force. PMID:27119090

  15. Evidence against dopamine D1/D2 receptor heteromers

    PubMed Central

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

    2014-01-01

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

  16. Dynamical functions of a 1D correlated quantum liquid

    NASA Astrophysics Data System (ADS)

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

    2008-10-01

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

  17. Synthesis and properties of a few 1-D cobaltous fumarates

    SciTech Connect

    Bora, Sanchay J.; Das, Birinchi K.

    2012-08-15

    Metal fumarates are often studied in the context of metal organic framework solids. Preparation, structure and properties of three cobalt(II) fumarates, viz. [Co(fum)(H{sub 2}O){sub 4}]{center_dot}H{sub 2}O 1, [Co(fum)(py){sub 2}(H{sub 2}O){sub 2}] 2, and [Co(fum)(4-CNpy){sub 2}(H{sub 2}O){sub 2}] 3 (fum=fumarate, py=pyridine, 4-CNpy=4-cyanopyridine) are described. All three are chain polymers involving bridging fumarato ligands between each pair of octahedral Co(II) centres, but while the first one is zigzag in structure, the latter two are linear. Indexed powder X-ray diffraction patterns, solid state electronic spectra and magnetic properties of the species are reported. Thermal decomposition behaviour of the compounds suggests that they may be suitable as precursors to make Co{sub 3}O{sub 4} via pyrolysis below 600 Degree-Sign C. - Graphical abstract: Structure and properties of three chain-polymeric cobalt(II) fumarates are described. Highlights: Black-Right-Pointing-Pointer Three fumarate bridged 1-D coordination polymers of cobalt(II) are reported. Black-Right-Pointing-Pointer While Co(II) fumarate pentahydrate is zigzag, the species having both pyridine and water as co-ligands are linear in structure. Black-Right-Pointing-Pointer Prominent lines in the powder X-ray diffraction patterns have been indexed. Black-Right-Pointing-Pointer Thermal decomposition of the species yields Co{sub 3}O{sub 4} as the final product.

  18. 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.

  19. 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

  20. Demonstrating Diffusion

    ERIC Educational Resources Information Center

    Foy, Barry G.

    1977-01-01

    Two demonstrations are described. Materials and instructions for demonstrating movement of molecules into cytoplasm using agar blocks, phenolphthalein, and sodium hydroxide are given. A simple method for demonstrating that the rate of diffusion of a gas is inversely proportional to its molecular weight is also presented. (AJ)

  1. Defusing Diffusion

    ERIC Educational Resources Information Center

    Dou, Remy; Hogan, DaNel; Kossover, Mark; Spuck, Timothy; Young, Sarah

    2013-01-01

    Diffusion has often been taught in science courses as one of the primary ways by which molecules travel, particularly within organisms. For years, classroom teachers have used the same common demonstrations to illustrate this concept (e.g., placing drops of food coloring in a beaker of water). Most of the time, the main contributor to the motion…

  2. Relativistic diffusion

    NASA Astrophysics Data System (ADS)

    Haba, Z.

    2009-02-01

    We discuss relativistic diffusion in proper time in the approach of Schay (Ph.D. thesis, Princeton University, Princeton, NJ, 1961) and Dudley [Ark. Mat. 6, 241 (1965)]. We derive (Langevin) stochastic differential equations in various coordinates. We show that in some coordinates the stochastic differential equations become linear. We obtain momentum probability distribution in an explicit form. We discuss a relativistic particle diffusing in an external electromagnetic field. We solve the Langevin equations in the case of parallel electric and magnetic fields. We derive a kinetic equation for the evolution of the probability distribution. We discuss drag terms leading to an equilibrium distribution. The relativistic analog of the Ornstein-Uhlenbeck process is not unique. We show that if the drag comes from a diffusion approximation to the master equation then its form is strongly restricted. The drag leading to the Tsallis equilibrium distribution satisfies this restriction whereas the one of the Jüttner distribution does not. We show that any function of the relativistic energy can be the equilibrium distribution for a particle in a static electric field. A preliminary study of the time evolution with friction is presented. It is shown that the problem is equivalent to quantum mechanics of a particle moving on a hyperboloid with a potential determined by the drag. A relation to diffusions appearing in heavy ion collisions is briefly discussed.

  3. Relativistic diffusion.

    PubMed

    Haba, Z

    2009-02-01

    We discuss relativistic diffusion in proper time in the approach of Schay (Ph.D. thesis, Princeton University, Princeton, NJ, 1961) and Dudley [Ark. Mat. 6, 241 (1965)]. We derive (Langevin) stochastic differential equations in various coordinates. We show that in some coordinates the stochastic differential equations become linear. We obtain momentum probability distribution in an explicit form. We discuss a relativistic particle diffusing in an external electromagnetic field. We solve the Langevin equations in the case of parallel electric and magnetic fields. We derive a kinetic equation for the evolution of the probability distribution. We discuss drag terms leading to an equilibrium distribution. The relativistic analog of the Ornstein-Uhlenbeck process is not unique. We show that if the drag comes from a diffusion approximation to the master equation then its form is strongly restricted. The drag leading to the Tsallis equilibrium distribution satisfies this restriction whereas the one of the Jüttner distribution does not. We show that any function of the relativistic energy can be the equilibrium distribution for a particle in a static electric field. A preliminary study of the time evolution with friction is presented. It is shown that the problem is equivalent to quantum mechanics of a particle moving on a hyperboloid with a potential determined by the drag. A relation to diffusions appearing in heavy ion collisions is briefly discussed. PMID:19391727

  4. 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. PMID:26714478

  5. 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...

  6. 1D-Simulation of Thermonuclear Target Compression and Burning for Laser Facility NIF and LMJ

    SciTech Connect

    Valiev, R. Zh.; Chizhkov, M. N.; Karlyhanov, N. G.; Lusganova, O. V.; Lykov, V. A.; Netsvetayev, D. S.; Timakova, M. S.

    2006-08-03

    The high-power laser facilities NIF and LMJ with the pulse energy as high as 2 MJ are being created in the USA and France. The basic cryogenic indirect-drive targets for thermonuclear ignition on these facilities are a spherical shell from polystyrene doped with oxygen and bromine. (CH+5%O+0,25%Br), whose inner surface is covered with DT-ice layer. The central region of targets is filled with DT-gas. The targets for NIF and LMJ have different external radii (1,11 and 1,215 mm, correspondingly), masses of DT-fuel (210 icy 310 {mu}g), X-ray radiation temperature dependences in time. The thermonuclear yield from the NIF target calculated with LASNEX code is 15 MJ, the yield from the LMJ target calculated with FCI1 code is 25.4 MJ. In RFNC-VNIITF calculations of compression and burning of basic NIF and LMJ targets were performed by using of the 1D ERA code in the spectral diffusion approximation for radiation transfer. We used tabulated opacity calculated by the mean ion model. Thermonuclear yield calculated with ERA code is about 18 MJ for the NIF target and nearly 23 MJ for the LMJ target. Calculated yields are in good agreement with published results. Performed calculations justified the possibility to simulate ICF targets in RFNC-VNIITF. In paper are also presented analysis results of target sensitivity to opacity and X-ray temperature variations.

  7. HELIOS-CR A 1-D radiation-magnetohydrodynamics code with inline atomic kinetics modeling

    NASA Astrophysics Data System (ADS)

    Macfarlane, J. J.; Golovkin, I. E.; Woodruff, P. R.

    2006-05-01

    HELIOS-CR is a user-oriented 1D radiation-magnetohydrodynamics code to simulate the dynamic evolution of laser-produced plasmas and z-pinch plasmas. It includes an in-line collisional-radiative (CR) model for computing non-LTE atomic level populations at each time step of the hydrodynamics simulation. HELIOS-CR has been designed for ease of use, and is well-suited for experimentalists, as well as graduate and undergraduate student researchers. The energy equations employed include models for laser energy deposition, radiation from external sources, and high-current discharges. Radiative transport can be calculated using either a multi-frequency flux-limited diffusion model, or a multi-frequency, multi-angle short characteristics model. HELIOS-CR supports the use of SESAME equation of state (EOS) tables, PROPACEOS EOS/multi-group opacity data tables, and non-LTE plasma properties computed using the inline CR modeling. Time-, space-, and frequency-dependent results from HELIOS-CR calculations are readily displayed with the HydroPLOT graphics tool. In addition, the results of HELIOS simulations can be post-processed using the SPECT3D Imaging and Spectral Analysis Suite to generate images and spectra that can be directly compared with experimental measurements. The HELIOS-CR package runs on Windows, Linux, and Mac OSX platforms, and includes online documentation. We will discuss the major features of HELIOS-CR, and present example results from simulations.

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

    NASA Astrophysics Data System (ADS)

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

    2009-02-01

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

  9. From nonfinite to finite 1D arrays of origami tiles.

    PubMed

    Wu, Tsai Chin; Rahman, Masudur; Norton, Michael L

    2014-06-17

    average solution structures for blocks is more readily achieved using computer models than using direct imaging methods. The development of scalable 1D-origami arrays composed of uniquely addressable components is a logical, if not necessary, step in the evolution of higher order fully addressable structures. Our research into the fabrication of arrays has led us to generate a listing of several important areas of future endeavor. Of high importance is the re-enforcement of the mechanical properties of the building blocks and the organization of multiple arrays on a surface of technological importance. While addressing this short list of barriers to progress will prove challenging, coherent development along each of these lines of inquiry will accelerate the appearance of commercial scale molecular manufacturing. PMID:24803094

  10. Genetic variation in aldo-keto reductase 1D1 (AKR1D1) affects the expression and activity of multiple cytochrome P450s.

    PubMed

    Chaudhry, Amarjit S; Thirumaran, Ranjit K; Yasuda, Kazuto; Yang, Xia; Fan, Yiping; Strom, Stephen C; Schuetz, Erin G

    2013-08-01

    Human liver gene regulatory (Bayesian) network analysis was previously used to identify a cytochrome P450 (P450) gene subnetwork with Aldo-keto reductase 1D1 (AKR1D1) as a key regulatory driver of this subnetwork. This study assessed the biologic importance of AKR1D1 [a key enzyme in the synthesis of bile acids, ligand activators of farnesoid X receptor (FXR), pregnane X receptor (PXR), and constitutive androstane receptor (CAR), known transcriptional regulators of P450s] to hepatic P450 expression. Overexpression of AKR1D1 in primary human hepatocytes led to increased expression of CYP3A4, CYP2C8, CYP2C9, CYP2C19, and CYP2B6. Conversely, AKR1D1 knockdown decreased expression of these P450s. We resequenced AKR1D1 from 98 donor livers and identified a 3'-untranslated region (UTR) (rs1872930) single nucleotide polymorphism (SNP) significantly associated with higher AKR1D1 mRNA expression. AKR1D1 3'-UTR-luciferase reporter studies showed that the variant allele resulted in higher luciferase activity, suggesting that the SNP increases AKR1D1 mRNA stability and/or translation efficiency. Consistent with AKR1D1's putative role as a driver of the P450 subnetwork, the AKR1D1 3'-UTR SNP was significantly associated with increased hepatic mRNA expression of multiple P450s (CYP3A4, CYP2C8, CYP2C9, CYP2C19, and CYP2B6) and CYP3A4, CYP2C8, CYP2C19, and CYP2B6 activities. After adjusting for multiple testing, the association remained significant for AKR1D1, CYP2C9, and CYP2C8 mRNA expression and CYP2C8 activity. These results provide new insights into the variation in expression and activity of P450s that can account for interindividual differences in drug metabolism/efficacy and adverse drug events. In conclusion, we provide the first experimental evidence supporting a role for AKR1D1 as a key genetic regulator of the P450 network. PMID:23704699

  11. Diffusion bonding

    DOEpatents

    Anderson, Robert C.

    1976-06-22

    1. A method for joining beryllium to beryllium by diffusion bonding, comprising the steps of coating at least one surface portion of at least two beryllium pieces with nickel, positioning a coated surface portion in a contiguous relationship with an other surface portion, subjecting the contiguously disposed surface portions to an environment having an atmosphere at a pressure lower than ambient pressure, applying a force upon the beryllium pieces for causing the contiguous surface portions to abut against each other, heating the contiguous surface portions to a maximum temperature less than the melting temperature of the beryllium, substantially uniformly decreasing the applied force while increasing the temperature after attaining a temperature substantially above room temperature, and maintaining a portion of the applied force at a temperature corresponding to about maximum temperature for a duration sufficient to effect the diffusion bond between the contiguous surface portions.

  12. 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.

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

    PubMed

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

    2016-03-01

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

  14. EEF1D modulates proliferation and epithelial-mesenchymal transition in oral squamous cell carcinoma.

    PubMed

    Flores, Isadora L; Kawahara, Rebeca; Miguel, Márcia C C; Granato, Daniela C; Domingues, Romênia R; Macedo, Carolina C S; Carnielli, Carolina M; Yokoo, Sami; Rodrigues, Priscila C; Monteiro, Bárbara V B; Oliveira, Carine E; Salmon, Cristiane R; Nociti, Francisco H; Lopes, Márcio A; Santos-Silva, Alan; Winck, Flavia V; Coletta, Ricardo D; Paes Leme, Adriana F

    2016-05-01

    EEF1D (eukaryotic translation elongation factor 1δ) is a subunit of the elongation factor 1 complex of proteins that mediates the elongation process during protein synthesis via enzymatic delivery of aminoacyl-tRNAs to the ribosome. Although the functions of EEF1D in the translation process are recognized, EEF1D expression was found to be unbalanced in tumours. In the present study, we demonstrate the overexpression of EEF1D in OSCC (oral squamous cell carcinoma), and revealed that EEF1D and protein interaction partners promote the activation of cyclin D1 and vimentin proteins. EEF1D knockdown in OSCC reduced cell proliferation and induced EMT (epithelial-mesenchymal transition) phenotypes, including cell invasion. Taken together, these results define EEF1D as a critical inducer of OSCC proliferation and EMT. PMID:26823560

  15. Numerical Evaluation of Lateral Diffusion Inside Diffusive Gradients in Thin Films Samplers

    PubMed Central

    2015-01-01

    Using numerical simulation of diffusion inside diffusive gradients in thin films (DGT) samplers, we show that the effect of lateral diffusion inside the sampler on the solute flux into the sampler is a nonlinear function of the diffusion layer thickness and the physical sampling window size. In contrast, earlier work concluded that this effect was constant irrespective of parameters of the sampler geometry. The flux increase caused by lateral diffusion inside the sampler was determined to be ∼8.8% for standard samplers, which is considerably lower than the previous estimate of ∼20%. Lateral diffusion is also propagated to the diffusive boundary layer (DBL), where it leads to a slightly stronger decrease in the mass uptake than suggested by the common 1D diffusion model that is applied for evaluating DGT results. We introduce a simple correction procedure for lateral diffusion and demonstrate how the effect of lateral diffusion on diffusion in the DBL can be accounted for. These corrections often result in better estimates of the DBL thickness (δ) and the DGT-measured concentration than earlier approaches and will contribute to more accurate concentration measurements in solute monitoring in waters. PMID:25877251

  16. An asymptotic homogenized neutron diffusion approximation. II. Numerical comparisons

    SciTech Connect

    Trahan, T. J.; Larsen, E. W.

    2012-07-01

    In a companion paper, a monoenergetic, homogenized, anisotropic diffusion equation is derived asymptotically for large, 3-D, multiplying systems with a periodic lattice structure [1]. In the present paper, this approximation is briefly compared to several other well known diffusion approximations. Although the derivation is different, the asymptotic diffusion approximation matches that proposed by Deniz and Gelbard, and is closely related to those proposed by Benoist. The focus of this paper, however, is a numerical comparison of the various methods for simple reactor analysis problems in 1-D. The comparisons show that the asymptotic diffusion approximation provides a more accurate estimate of the eigenvalue than the Benoist diffusion approximations. However, the Benoist diffusion approximations and the asymptotic diffusion approximation provide very similar estimates of the neutron flux. The asymptotic method and the Benoist methods both outperform the standard homogenized diffusion approximation, with flux weighted cross sections. (authors)

  17. Endogenous N-terminal Domain Cleavage Modulates α1D-Adrenergic Receptor Pharmacodynamics.

    PubMed

    Kountz, Timothy S; Lee, Kyung-Soon; Aggarwal-Howarth, Stacey; Curran, Elizabeth; Park, Ji-Min; Harris, Dorathy-Ann; Stewart, Aaron; Hendrickson, Joseph; Camp, Nathan D; Wolf-Yadlin, Alejandro; Wang, Edith H; Scott, John D; Hague, Chris

    2016-08-26

    The α1D-adrenergic receptor (ADRA1D) is a key regulator of cardiovascular, prostate, and central nervous system functions. This clinically relevant G protein-coupled receptor has proven difficult to study, as it must form an obligate modular homodimer containing the PDZ proteins scribble and syntrophin or become retained in the endoplasmic reticulum as non-functional protein. We previously determined that targeted removal of the N-terminal (NT) 79 amino acids facilitates ADRA1D plasma membrane expression and agonist-stimulated functional responses. However, whether such an event occurs in physiological contexts was unknown. Herein, we report the ADRA1D is subjected to innate NT processing in cultured human cells. SNAP near-infrared imaging and tandem-affinity purification revealed the ADRA1D is expressed as both full-length and NT truncated forms in multiple human cell lines. Serial truncation mapping identified the cleavage site as Leu(90)/Val(91) in the 95-amino acid ADRA1D NT domain, suggesting human cells express a Δ1-91 ADRA1D species. Tandem-affinity purification MS/MS and co-immunoprecipitation analysis indicate NT processing of ADRA1D is not required to form scribble-syntrophin macromolecular complexes. Yet, label-free dynamic mass redistribution signaling assays demonstrate that Δ1-91 ADRA1D agonist responses were greater than WT ADRA1D. Mutagenesis of the cleavage site nullified the processing event, resulting in ADRA1D agonist responses less than the WT receptor. Thus, we propose that processing of the ADRA1D NT domain is a physiological mechanism employed by cells to generate a functional ADRA1D isoform with optimal pharmacodynamic properties. PMID:27382054

  18. Quantum diffusion

    SciTech Connect

    Habib, S.

    1994-10-01

    We consider a simple quantum system subjected to a classical random force. Under certain conditions it is shown that the noise-averaged Wigner function of the system follows an integro-differential stochastic Liouville equation. In the simple case of polynomial noise-couplings this equation reduces to a generalized Fokker-Planck form. With nonlinear noise injection new ``quantum diffusion`` terms rise that have no counterpart in the classical case. Two special examples that are not of a Fokker-Planck form are discussed: the first with a localized noise source and the other with a spatially modulated noise source.

  19. DIFFUSION PUMP

    DOEpatents

    Levenson, L.

    1963-09-01

    A high-vacuum diffusion pump is described, featuring a novel housing geometry for enhancing pumping speed. An upright, cylindrical lower housing portion is surmounted by a concentric, upright, cylindrical upper housing portion of substantially larger diameter; an uppermost nozzle, disposed concentrically within the upper portion, is adapted to eject downwardly a conical sheet of liquid outwardly to impinge upon the uppermost extremity of the interior wall of the lower portion. Preferably this nozzle is mounted upon a pedestal rising coaxially from within the lower portion and projecting up into said upper portion. (AEC)

  20. You Don't Need Richards'... A New General 1-D Vadose Zone Solution Method that is Reliable

    NASA Astrophysics Data System (ADS)

    Ogden, F. L.; Lai, W.; Zhu, J.; Steinke, R. C.; Talbot, C. A.

    2015-12-01

    Hydrologic modelers and mathematicians have strived to improve 1-D Richards' equation (RE) solution reliability for predicting vadose zone fluxes. Despite advances in computing power and the numerical solution of partial differential equations since Richards first published the RE in 1931, the solution remains unreliable. That is to say that there is no guarantee that for a particular set of soil constitutive relations, moisture profile conditions, or forcing input that a numerical RE solver will converge to an answer. This risk of non-convergence renders prohibitive the use of RE solvers in hydrological models that need perhaps millions of infiltration solutions. In lieu of using unreliable numerical RE solutions, researchers have developed a wide array of approximate solutions that more-or-less mimic the behavior of the RE, with some notable deficiencies such as parameter insensitivity or divergence over time. The improved Talbot-Ogden (T-O) finite water-content scheme was shown by Ogden et al. (2015) to be an extremely good approximation of the 1-D RE solution, with a difference in cumulative infiltration of only 0.2 percent over an 8 month simulation comparing the improved T-O scheme with a RE numerical solver. The reason is that the newly-derived fundamental flow equation that underpins the improved T-O method is equivalent to the RE minus a term that is equal to the diffusive flux divided by the slope of the wetting front. Because the diffusive flux has zero mean, this term is not important in calculating the mean flux. The wetting front slope is near infinite (sharp) in coarser soils that produce more significant hydrological interactions between surface and ground waters, which also makes this missing term 1) disappear in the limit, and, 2) create stability challenges for the numerical solution of RE. The improved T-O method is a replacement for the 1-D RE in soils that can be simulated as homogeneous layers, where the user is willing to neglect the effects

  1. Molecular characterization of the maize Rp1-D rust resistance haplotype and its mutants.

    PubMed Central

    Collins, N; Drake, J; Ayliffe, M; Sun, Q; Ellis, J; Hulbert, S; Pryor, T

    1999-01-01

    The Rp1-D gene for resistance to maize common rust (Puccinia sorghi) is a member of a complex locus (haplotype) composed of Rp1-D and approximately eight other gene homologs. The identity of Rp1-D was demonstrated by using two independent gene-tagging approaches with the transposons Mutator and Dissociation. PIC20, a disease resistance (R) gene analog probe previously mapped to the rp1 locus, detected insertion of Dissociation in an Rp1-D mutation and excision in three revertants. Independent libraries probed with the PIC20 or Mutator probes resulted in isolation of the same gene sequence. Rp1-D belongs to the nucleotide binding site, leucine-rich repeat class of R genes. However, unlike the rust resistance genes M and L6 from flax, the maize Rp1-D gene does not encode an N-terminal domain with similarity to the signal transduction domains of the Drosophila Toll protein and mammalian interleukin-1 receptor. Although the abundance of transcripts of genes from the rp1 complex changed with leaf age, there was no evidence of any change due to inoculation with avirulent or virulent rust biotypes. A set of 27 Rp1-D mutants displayed at least nine different deletions of Rp1-D gene family members that were consistent with unequal crossing-over events. One mutation (Rp1-D*-24) resulted in deletion of all but one gene family member. Other unique deletions were observed in the disease lesion mimic Rp1-D*-21 and the partially susceptible mutant Rp1-D*-5. Different rp1 specificities have distinct DNA fingerprints (haplotypes). Analysis of recombinants between rp1 specificities indicated that recombination had occurred within the rp1 gene complex. Similar analyses indicated that the rust R genes at the rp5 locus, 2 centimorgans distal to rp1, are not closely related to Rp1-D. PMID:10402435

  2. Molecular characterization of the maize Rp1-D rust resistance haplotype and its mutants.

    PubMed

    Collins, N; Drake, J; Ayliffe, M; Sun, Q; Ellis, J; Hulbert, S; Pryor, T

    1999-07-01

    The Rp1-D gene for resistance to maize common rust (Puccinia sorghi) is a member of a complex locus (haplotype) composed of Rp1-D and approximately eight other gene homologs. The identity of Rp1-D was demonstrated by using two independent gene-tagging approaches with the transposons Mutator and Dissociation. PIC20, a disease resistance (R) gene analog probe previously mapped to the rp1 locus, detected insertion of Dissociation in an Rp1-D mutation and excision in three revertants. Independent libraries probed with the PIC20 or Mutator probes resulted in isolation of the same gene sequence. Rp1-D belongs to the nucleotide binding site, leucine-rich repeat class of R genes. However, unlike the rust resistance genes M and L6 from flax, the maize Rp1-D gene does not encode an N-terminal domain with similarity to the signal transduction domains of the Drosophila Toll protein and mammalian interleukin-1 receptor. Although the abundance of transcripts of genes from the rp1 complex changed with leaf age, there was no evidence of any change due to inoculation with avirulent or virulent rust biotypes. A set of 27 Rp1-D mutants displayed at least nine different deletions of Rp1-D gene family members that were consistent with unequal crossing-over events. One mutation (Rp1-D*-24) resulted in deletion of all but one gene family member. Other unique deletions were observed in the disease lesion mimic Rp1-D*-21 and the partially susceptible mutant Rp1-D*-5. Different rp1 specificities have distinct DNA fingerprints (haplotypes). Analysis of recombinants between rp1 specificities indicated that recombination had occurred within the rp1 gene complex. Similar analyses indicated that the rust R genes at the rp5 locus, 2 centimorgans distal to rp1, are not closely related to Rp1-D. PMID:10402435

  3. 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.

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

    NASA Astrophysics Data System (ADS)

    Johnson, R. H.; Morrison, S.; Morris, S.; Tigar, A.; Dam, W. L.; Dayvault, J.

    2015-12-01

    At many U.S. Department of Energy Office of Legacy Management sites, 100 year natural flushing was selected as a remedial option for groundwater uranium plumes. However, current data indicate that natural flushing is not occurring as quickly as expected and solid-phase and aqueous uranium concentrations are persistent. At the Grand Junction, Colorado office site, column testing was completed on core collected below an area where uranium mill tailings have been removed. The total uranium concentration in this core was 13.2 mg/kg and the column was flushed with laboratory-created water with no uranium and chemistry similar to the nearby Gunnison River. The core was flushed for a total of 91 pore volumes producing a maximum effluent uranium concentration of 6,110 μg/L at 2.1 pore volumes and a minimum uranium concentration of 36.2 μg/L at the final pore volume. These results indicate complex geochemical reactions at small pore volumes and a long tailing affect at greater pore volumes. Stop flow data indicate the occurrence of non-equilibrium processes that create uranium concentration rebound. These data confirm the potential for plume persistence, which is occurring at the field scale. 1D reactive transport modeling was completed using PHREEQC (geochemical model) and calibrated to the column test data manually and using PEST (inverse modeling calibration routine). Processes of sorption, dual porosity with diffusion, mineral dissolution, dispersion, and cation exchange were evaluated separately and in combination. The calibration results indicate that sorption and dual porosity are major processes in explaining the column test data. These processes are also supported by fission track photographs that show solid-phase uranium residing in less mobile pore spaces. These procedures provide valuable information on plume persistence and secondary source processes that may be used to better inform and evaluate remedial strategies, including natural flushing.

  5. Testing the early Mars H2-CO2 greenhouse hypothesis with a 1-D photochemical model

    NASA Astrophysics Data System (ADS)

    Batalha, Natasha; Domagal-Goldman, Shawn D.; Ramirez, Ramses; Kasting, James F.

    2015-09-01

    A recent study by Ramirez et al. (Ramirez, R.M. et al. [2014]. Nat. Geosci. 7(1), 59-63.) demonstrated that an atmosphere with 1.3-4 bar of CO2 and H2O, in addition to 5-20% H2, could have raised the mean annual and global surface temperature of early Mars above the freezing point of water. Such warm temperatures appear necessary to generate the rainfall (or snowfall) amounts required to carve the ancient martian valleys. Here, we use our best estimates for early martian outgassing rates, along with a 1-D photochemical model, to assess the conversion efficiency of CO, CH4, and H2S to CO2, SO2, and H2. Our outgassing estimates assume that Mars was actively recycling volatiles between its crust and interior, as Earth does today. H2 production from serpentinization and deposition of banded iron-formations is also considered. Under these assumptions, maintaining an H2 concentration of ˜1-2% by volume is achievable, but reaching 5% H2 requires additional H2 sources or a slowing of the hydrogen escape rate below the diffusion limit. If the early martian atmosphere was indeed H2-rich, we might be able to see evidence of this in the rock record. The hypothesis proposed here is consistent with new data from the Curiosity Rover, which show evidence for a long-lived lake in Gale Crater near Mt. Sharp. It is also consistent with measured oxygen fugacities of martian meteorites, which show evidence for progressive mantle oxidation over time.

  6. 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. PMID:27171200

  7. Individual speckle diffraction based 1D and 2D Random Grating Fabrication for detector and solar energy harvesting applications.

    PubMed

    Bingi, Jayachandra; Murukeshan, Vadakke Matham

    2016-01-01

    Laser speckles and speckle patterns, which are formed by the random interference of scattered waves from optically rough surfaces, have found tremendous applications in a wide range of metrological and biomedical fields. Here, we demonstrate a novel edge diffraction phenomenon of individual speckle for the fabrication of 1D and 2D micron and sub-micron size random gratings. These random gratings exhibit broadband response with interesting diffusive diffraction patterns. As an immediate application for solar energy harvesting, significant reduction in transmission and enhanced absorption in thin "Si-random grating-Si" sandwich structure is demonstrated. This work has multifaceted significance where we exploited the individual speckle diffraction properties for the first time. Besides the solar harvesting applications, random gratings are suitable structures for fabrication of theoretically proposed random quantum well IR detectors and hence expected that this work will augur well for such studies in the near future. PMID:26842242

  8. Individual speckle diffraction based 1D and 2D Random Grating Fabrication for detector and solar energy harvesting applications

    PubMed Central

    Bingi, Jayachandra; Murukeshan, Vadakke Matham

    2016-01-01

    Laser speckles and speckle patterns, which are formed by the random interference of scattered waves from optically rough surfaces, have found tremendous applications in a wide range of metrological and biomedical fields. Here, we demonstrate a novel edge diffraction phenomenon of individual speckle for the fabrication of 1D and 2D micron and sub-micron size random gratings. These random gratings exhibit broadband response with interesting diffusive diffraction patterns. As an immediate application for solar energy harvesting, significant reduction in transmission and enhanced absorption in thin “Si-random grating-Si” sandwich structure is demonstrated. This work has multifaceted significance where we exploited the individual speckle diffraction properties for the first time. Besides the solar harvesting applications, random gratings are suitable structures for fabrication of theoretically proposed random quantum well IR detectors and hence expected that this work will augur well for such studies in the near future. PMID:26842242

  9. Individual speckle diffraction based 1D and 2D Random Grating Fabrication for detector and solar energy harvesting applications

    NASA Astrophysics Data System (ADS)

    Bingi, Jayachandra; Murukeshan, Vadakke Matham

    2016-02-01

    Laser speckles and speckle patterns, which are formed by the random interference of scattered waves from optically rough surfaces, have found tremendous applications in a wide range of metrological and biomedical fields. Here, we demonstrate a novel edge diffraction phenomenon of individual speckle for the fabrication of 1D and 2D micron and sub-micron size random gratings. These random gratings exhibit broadband response with interesting diffusive diffraction patterns. As an immediate application for solar energy harvesting, significant reduction in transmission and enhanced absorption in thin “Si-random grating-Si” sandwich structure is demonstrated. This work has multifaceted significance where we exploited the individual speckle diffraction properties for the first time. Besides the solar harvesting applications, random gratings are suitable structures for fabrication of theoretically proposed random quantum well IR detectors and hence expected that this work will augur well for such studies in the near future.

  10. Comparative effects of nodularin and microcystin-LR in zebrafish: 1. Uptake by organic anion transporting polypeptide Oatp1d1 (Slco1d1).

    PubMed

    Faltermann, Susanne; Prétôt, René; Pernthaler, Jakob; Fent, Karl

    2016-02-01

    Microcystin-LR (MC-LR) and nodularin are hepatotoxins produced by several cyanobacterial species. Their toxicity is based on active cellular uptake and subsequent inhibition of protein phosphatases PP1/2A, leading to hyperphosphorylation and cell death. To date, uptake of MC-LR and nodularin in fish is poorly understood. Here, we investigated the role of the organic anion transporting polypeptide Oatp1d1 in zebrafish (drOatp1d1, Slco1d1) in cellular uptake in zebrafish. We stably transfected CHO and HEK293 cell lines expressing drOatp1d1. In both transfectants, uptake of MC-LR and nodularin was demonstrated by competitive inhibition of uptake with fluorescent substrate lucifer yellow. Direct uptake of MC-LR was demonstrated by immunostaining, and indirectly by the high cytotoxicity in stable transfectants. By means of a synthesized fluorescent labeled MC-LR derivative, direct uptake was further confirmed in HEK293 cells expressing drOatp1d1. Additionally, uptake and toxicity was investigated in the permanent zebrafish liver cell line ZFL. These cells had only a low relative abundance of drOatp1d1, drOatp2b1 and drOatp1f transcripts, which correlated with the lack of MC-LR induced cytotoxicity and transcriptional changes of genes indicative of endoplasmic reticulum stress, a known effect of this toxin. Our study demonstrates that drOatp1d1 functions as an uptake transporter for both MC-LR and nodularin in zebrafish. PMID:26769064

  11. 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.

  12. The CG-1D Neutron Imaging Beamline at the Oak Ridge National Laboratory High Flux Isotope Reactor

    NASA Astrophysics Data System (ADS)

    Santodonato, Lou; Bilheux, Hassina; Bailey, Barton; Bilheux, Jean; Nguyen, Phong; Tremsin, Anton; Selby, Doug; Walker, Lakeisha

    The Oak Ridge National Laboratory Neutron Sciences Directorate has installed a neutron imaging beamline at the High Flux Isotope Reactor (HFIR) cold guide hall. CG-1D is one of the three instruments that make up the CG1 instrument suite. The beamline optics and detector have recently been upgraded to meet the needs of the neutron imaging community (better "smoothing" of guide system artifacts, higher flux or spatial resolution). These upgrades comprise a new diffuser/aperture system, two new detectors, a He-filled flight tube and silicon (Si) windows. Shielding inside the flight tube, beam scrapers and a beam stop ensure that biological dose is less than 50 μSv/hr outside of the radiation boundary. A set of diffusers and apertures (pinhole geometry) has been installed at the exit of the guide system to allow motorized L/D variation. Samples sit on a translation/rotation stage for alignment and tomography purposes. Detectors for the CG-1D beamline are (1) an ANDOR DW936 charge coupled device (CCD) camera with a field of view of approximately 7 cm x 7 cm and ∼ 80 microns spatial resolution and 1 frame per second time resolution, (2) a new Micro-Channel Plate (MCP) detector with a 2.8 cm x 2.8 cm field of view and 55 microns spatial resolution, and 5 μs timing capability. 6LiF/ZnS scintillators of thickness varying from 50 to 200 microns are being used at this facility. An overview of the beamline upgrade and preliminary data is presented here.

  13. The CG-1D neutron imaging beamline at the Oak Ridge National Laboratory High Flux Isotope Reactor

    SciTech Connect

    Santodonato, Louis J; Bilheux, Hassina Z; Bailey, William Barton; Bilheux, Jean-Christophe; Nguyen, Phong T; Tremsin, Anton S; Selby, Douglas L; Walker, Lakeisha MH

    2015-01-01

    The Oak Ridge National Laboratory Neutron Sciences Directorate has installed a neutron imaging beamline at the High Flux Isotope Reactor (HFIR) cold guide hall. CG-1D is one of the three instruments that make up the CG1 instrument suite. The beamline optics and detector have recently been upgraded to meet the needs of the neutron imaging community (better smoothing of guide system artifacts, higher flux or spatial resolution). These upgrades comprise a new diffuser/aperture system, two new detectors, a He-filled flight tube and silicon (Si) windows. Shielding inside the flight tube, beam scrapers and a beam stop ensure that biological dose is less than 50 Sv/hr outside of the radiation boundary. A set of diffusers and apertures (pinhole geometry) has been installed at the exit of the guide system to allow motorized L/D variation. Samples sit on a translation/rotation stage for alignment and tomography purposes. Detectors for the CG-1D beamline are (1) an ANDOR DW936 charge coupled device (CCD) camera with a field of view of approximately 7 cm x 7 cm and ~ 80 microns spatial resolution and 1 frame per second time resolution, (2) a new Micro-Channel Plate (MCP) detector with a 2.8 cm x 2.8 cm field of view and 55 microns spatial resolution, and 5 s timing capability. 6LiF/ZnS scintillators of thickness varying from 50 to 200 microns are being used at this facility. An overview of the beamline upgrade and preliminary data is presented here.

  14. 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

  15. 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.

  16. 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.

  17. The actin cytoskeleton modulates the activation of iNKT cells by segregating CD1d nanoclusters on antigen-presenting cells.

    PubMed

    Torreno-Pina, Juan A; Manzo, Carlo; Salio, Mariolina; Aichinger, Michael C; Oddone, Anna; Lakadamyali, Melike; Shepherd, Dawn; Besra, Gurdyal S; Cerundolo, Vincenzo; Garcia-Parajo, Maria F

    2016-02-01

    Invariant natural killer T (iNKT) cells recognize endogenous and exogenous lipid antigens presented in the context of CD1d molecules. The ability of iNKT cells to recognize endogenous antigens represents a distinct immune recognition strategy, which underscores the constitutive memory phenotype of iNKT cells and their activation during inflammatory conditions. However, the mechanisms regulating such "tonic" activation of iNKT cells remain unclear. Here, we show that the spatiotemporal distribution of CD1d molecules on the surface of antigen-presenting cells (APCs) modulates activation of iNKT cells. By using superresolution microscopy, we show that CD1d molecules form nanoclusters at the cell surface of APCs, and their size and density are constrained by the actin cytoskeleton. Dual-color single-particle tracking revealed that diffusing CD1d nanoclusters are actively arrested by the actin cytoskeleton, preventing their further coalescence. Formation of larger nanoclusters occurs in the absence of interactions between CD1d cytosolic tail and the actin cytoskeleton and correlates with enhanced iNKT cell activation. Importantly and consistently with iNKT cell activation during inflammatory conditions, exposure of APCs to the Toll-like receptor 7/8 agonist R848 increases nanocluster density and iNKT cell activation. Overall, these results define a previously unidentified mechanism that modulates iNKT cell autoreactivity based on the tight control by the APC cytoskeleton of the sizes and densities of endogenous antigen-loaded CD1d nanoclusters. PMID:26798067

  18. The actin cytoskeleton modulates the activation of iNKT cells by segregating CD1d nanoclusters on antigen-presenting cells

    PubMed Central

    Torreno-Pina, Juan A.; Manzo, Carlo; Salio, Mariolina; Aichinger, Michael C.; Oddone, Anna; Lakadamyali, Melike; Shepherd, Dawn; Besra, Gurdyal S.; Cerundolo, Vincenzo

    2016-01-01

    Invariant natural killer T (iNKT) cells recognize endogenous and exogenous lipid antigens presented in the context of CD1d molecules. The ability of iNKT cells to recognize endogenous antigens represents a distinct immune recognition strategy, which underscores the constitutive memory phenotype of iNKT cells and their activation during inflammatory conditions. However, the mechanisms regulating such “tonic” activation of iNKT cells remain unclear. Here, we show that the spatiotemporal distribution of CD1d molecules on the surface of antigen-presenting cells (APCs) modulates activation of iNKT cells. By using superresolution microscopy, we show that CD1d molecules form nanoclusters at the cell surface of APCs, and their size and density are constrained by the actin cytoskeleton. Dual-color single-particle tracking revealed that diffusing CD1d nanoclusters are actively arrested by the actin cytoskeleton, preventing their further coalescence. Formation of larger nanoclusters occurs in the absence of interactions between CD1d cytosolic tail and the actin cytoskeleton and correlates with enhanced iNKT cell activation. Importantly and consistently with iNKT cell activation during inflammatory conditions, exposure of APCs to the Toll-like receptor 7/8 agonist R848 increases nanocluster density and iNKT cell activation. Overall, these results define a previously unidentified mechanism that modulates iNKT cell autoreactivity based on the tight control by the APC cytoskeleton of the sizes and densities of endogenous antigen-loaded CD1d nanoclusters. PMID:26798067

  19. Diffusive Dynamics of Contact Formation in Disordered Polypeptides

    NASA Astrophysics Data System (ADS)

    Zerze, Gül H.; Mittal, Jeetain; Best, Robert B.

    2016-02-01

    Experiments measuring contact formation between probes in disordered chains provide information on the fundamental time scales relevant to protein folding. However, their interpretation usually relies on one-dimensional (1D) diffusion models, as do many experiments probing a single distance. Here, we use all-atom molecular simulations to capture both the time scales of contact formation, as well as the scaling with peptide length for tryptophan triplet quenching experiments, revealing the sensitivity of the experimental quenching times to the configurational space explored by the chain. We find a remarkable consistency between the results of the full calculation and from Szabo-Schulten-Schulten theory applied to a 1D diffusion model, supporting the validity of such models. The significant reduction in diffusion coefficient at the small probe separations which most influence quenching rate, suggests that contact formation and Förster resonance energy transfer correlation experiments provide complementary information on diffusivity.

  20. Diffusive Dynamics of Contact Formation in Disordered Polypeptides.

    PubMed

    Zerze, Gül H; Mittal, Jeetain; Best, Robert B

    2016-02-12

    Experiments measuring contact formation between probes in disordered chains provide information on the fundamental time scales relevant to protein folding. However, their interpretation usually relies on one-dimensional (1D) diffusion models, as do many experiments probing a single distance. Here, we use all-atom molecular simulations to capture both the time scales of contact formation, as well as the scaling with peptide length for tryptophan triplet quenching experiments, revealing the sensitivity of the experimental quenching times to the configurational space explored by the chain. We find a remarkable consistency between the results of the full calculation and from Szabo-Schulten-Schulten theory applied to a 1D diffusion model, supporting the validity of such models. The significant reduction in diffusion coefficient at the small probe separations which most influence quenching rate, suggests that contact formation and Förster resonance energy transfer correlation experiments provide complementary information on diffusivity. PMID:26919016

  1. 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. PMID:26200093

  2. Correlation between inter-spin interaction and molecular dynamics of organic radicals in organic 1D nanochannels

    SciTech Connect

    Kobayashi, Hirokazu

    2015-12-31

    One-dimensional (1D) molecular chains of 4-substituted-2,2,6,6-tetramethyl-1-piperidinyloxyl (4-X-TEMPO) radicals were constructed in the crystalline 1D nanochannels of 2,4,6-tris(4-chlorophenoxy)-1,3,5-triazine (CLPOT) used as a template. The ESR spectra of CLPOT inclusion compounds (ICs) using 4-X-TEMPO were examined on the basis of spectral simulation using EasySpin program package for simulating and fitting ESR spectra. The ESR spectra of [(CLPOT){sub 2}-(TEMPO){sub 1.0}] IC were isotropic in the total range of temperatures. The peak-to-peak line width (ΔB{sub pp}) became monotonically narrower from 2.8 to 1.3 mT with increase in temperature in the range of 4.2–298 K. The effect of the rotational diffusion motion of TEMPO radicals in the CLPOT nanochannels for the inter-spin interaction of the [(CLPOT){sub 2}-(TEMPO){sub 1.0}] IC was found to be smaller than the case of [(TPP){sub 2}−(TEMPO){sub 1.0}] IC (TPP = tris(o-phenylenedioxy)cyclotriphosphazene) reported in our previous study. The ΔB{sub pp} of the [(CLPOT){sub 2}-(TEMPO){sub 1.0}] IC in the whole range of temperatures was much narrower than the estimation to be based on the Van Vleck’s formula for the second moment of the rigid lattice model where the electron spin can be considered as fixed; 11 mT of Gaussian line-width component. This suggests the possibility of exchange narrowing in the 1D organic-radical chains of the [(CLPOT){sub 2}-(TEMPO){sub 1.0}] IC. On the other hand, the ESR spectra of [(CLPOT){sub 2}-(MeO-TEMPO){sub 0.41}] IC (MeO-TEMPO = 4-methoxy-TEMPO) were reproduced by a superposition of major broad isotropic adsorption line and minor temperature-dependent modulated triplet component. This suggests that the IC has the part of 1D organic-radical chains and MeO-TEMPO molecules isolated in the CLPOT nanochannels.

  3. Correlation between inter-spin interaction and molecular dynamics of organic radicals in organic 1D nanochannels

    NASA Astrophysics Data System (ADS)

    Kobayashi, Hirokazu

    2015-12-01

    One-dimensional (1D) molecular chains of 4-substituted-2,2,6,6-tetramethyl-1-piperidinyloxyl (4-X-TEMPO) radicals were constructed in the crystalline 1D nanochannels of 2,4,6-tris(4-chlorophenoxy)-1,3,5-triazine (CLPOT) used as a template. The ESR spectra of CLPOT inclusion compounds (ICs) using 4-X-TEMPO were examined on the basis of spectral simulation using EasySpin program package for simulating and fitting ESR spectra. The ESR spectra of [(CLPOT)2-(TEMPO)1.0] IC were isotropic in the total range of temperatures. The peak-to-peak line width (ΔBpp) became monotonically narrower from 2.8 to 1.3 mT with increase in temperature in the range of 4.2-298 K. The effect of the rotational diffusion motion of TEMPO radicals in the CLPOT nanochannels for the inter-spin interaction of the [(CLPOT)2-(TEMPO)1.0] IC was found to be smaller than the case of [(TPP)2-(TEMPO)1.0] IC (TPP = tris(o-phenylenedioxy)cyclotriphosphazene) reported in our previous study. The ΔBpp of the [(CLPOT)2-(TEMPO)1.0] IC in the whole range of temperatures was much narrower than the estimation to be based on the Van Vleck's formula for the second moment of the rigid lattice model where the electron spin can be considered as fixed; 11 mT of Gaussian line-width component. This suggests the possibility of exchange narrowing in the 1D organic-radical chains of the [(CLPOT)2-(TEMPO)1.0] IC. On the other hand, the ESR spectra of [(CLPOT)2-(MeO-TEMPO)0.41] IC (MeO-TEMPO = 4-methoxy-TEMPO) were reproduced by a superposition of major broad isotropic adsorption line and minor temperature-dependent modulated triplet component. This suggests that the IC has the part of 1D organic-radical chains and MeO-TEMPO molecules isolated in the CLPOT nanochannels.

  4. Effects of 3 dimensional crystal geometry and orientation on 1D and 2D time-scale determinations of magmatic processes using olivine and orthopyroxene

    NASA Astrophysics Data System (ADS)

    Shea, Thomas; Krimer, Daniel; Costa, Fidel; Hammer, Julia

    2014-05-01

    One of the achievements in recent years in volcanology is the determination of time-scales of magmatic processes via diffusion in minerals and its addition to the petrologists' and volcanologists' toolbox. The method typically requires one-dimensional modeling of randomly cut crystals from two-dimensional thin sections. Here we address the question whether using 1D (traverse) or 2D (surface) datasets exploited from randomly cut 3D crystals introduces a bias or dispersion in the time-scales estimated, and how this error can be improved or eliminated. Computational simulations were performed using a concentration-dependent, finite-difference solution to the diffusion equation in 3D. The starting numerical models involved simple geometries (spheres, parallelepipeds), Mg/Fe zoning patterns (either normal or reverse), and isotropic diffusion coefficients. Subsequent models progressively incorporated more complexity, 3D olivines possessing representative polyhedral morphologies, diffusion anisotropy along the different crystallographic axes, and more intricate core-rim zoning patterns. Sections and profiles used to compare 1, 2 and 3D diffusion models were selected to be (1) parallel to the crystal axes, (2) randomly oriented but passing through the olivine center, or (3) randomly oriented and sectioned. Results show that time-scales estimated on randomly cut traverses (1D) or surfaces (2D) can be widely distributed around the actual durations of 3D diffusion (~0.2 to 10 times the true diffusion time). The magnitude over- or underestimations of duration are a complex combination of the geometry of the crystal, the zoning pattern, the orientation of the cuts with respect to the crystallographic axes, and the degree of diffusion anisotropy. Errors on estimated time-scales retrieved from such models may thus be significant. Drastic reductions in the uncertainty of calculated diffusion times can be obtained by following some simple guidelines during the course of data

  5. 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.

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

    PubMed Central

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

    2004-01-01

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

  7. 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.

  8. Parallel flow diffusion battery

    DOEpatents

    Yeh, Hsu-Chi; Cheng, Yung-Sung

    1984-08-07

    A parallel flow diffusion battery for determining the mass distribution of an aerosol has a plurality of diffusion cells mounted in parallel to an aerosol stream, each diffusion cell including a stack of mesh wire screens of different density.

  9. Parallel flow diffusion battery

    DOEpatents

    Yeh, H.C.; Cheng, Y.S.

    1984-01-01

    A parallel flow diffusion battery for determining the mass distribution of an aerosol has a plurality of diffusion cells mounted in parallel to an aerosol stream, each diffusion cell including a stack of mesh wire screens of different density.

  10. NIST Diffusion Data Center

    National Institute of Standards and Technology Data Gateway

    NIST Diffusion Data Center (Web, free access)   The NIST Diffusion Data Center is a collection of over 14,100 international papers, theses, and government reports on diffusion published before 1980.

  11. Species Specific Differences of CD1d Oligomer Loading In Vitro

    PubMed Central

    Paletta, Daniel; Fichtner, Alina Suzann; Starick, Lisa; Porcelli, Steven A.; Savage, Paul B.; Herrmann, Thomas

    2015-01-01

    CD1d molecules are MHC class I-like molecules that present glycolipids to iNKT cells. The highly conserved interaction between CD1d:α-Galactosylceramide (αGC) complexes and the iNKT TCR not only defines this population of αβ T cells but can also be used for its direct identification. Therefore, CD1d oligomers are a widely used tool for iNKT cell related investigations. To this end, the lipid chains of the antigen have to be inserted into the hydrophobic pockets of the CD1d binding cleft, often with help of surfactants. In this study, we investigated the influence of different surfactants (Triton X-100, Tween 20, Tyloxapol) on in vitro loading of CD1d molecules derived from four different species (human, mouse, rat and cotton rat) with αGC and derivatives carrying modifications of the acyl-chain (DB01-1, PBS44) and a 6-acetamido-6-deoxy-addition at the galactosyl head group (PBS57). We also compared rat CD1d dimers with tetramers and staining of an iNKT TCR transductant was used as readout for loading efficacy. The results underlined the importance of CD1d loading efficacy for proper analysis of iNKT TCR binding and demonstrated the necessity to adjust loading conditions for each oligomer/glycolipid combination. The efficient usage of surfactants as a tool for CD1d loading was revealed to be species-specific and depending on the origin of the CD1d producing cells. Additional variation of surfactant-dependent loading efficacy between tested glycolipids was influenced by the acyl-chain length and the modification of the galactosyl head group with PBS57 showing the least dependence on surfactants and the lowest degree of species-dependent differences. PMID:26599805

  12. FRACTIONAL PEARSON DIFFUSIONS

    PubMed Central

    Leonenko, Nikolai N.; Meerschaert, Mark M.

    2013-01-01

    Pearson diffusions are governed by diffusion equations with polynomial coefficients. Fractional Pearson diffusions are governed by the corresponding time-fractional diffusion equation. They are useful for modeling sub-diffusive phenomena, caused by particle sticking and trapping. This paper provides explicit strong solutions for fractional Pearson diffusions, using spectral methods. It also presents stochastic solutions, using a non-Markovian inverse stable time change. PMID:23626377

  13. 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.

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

    DOE PAGESBeta

    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.

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

    PubMed

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

    2015-01-01

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

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

    NASA Technical Reports Server (NTRS)

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

    1990-01-01

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

  17. 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

  18. A diffusion-diffusion model for percutaneous drug absorption.

    PubMed

    Kubota, K; Ishizaki, T

    1986-08-01

    Several theories describing percutaneous drug absorption have been proposed, incorporating the mathematical solutions of differential equations describing percutaneous drug absorption processes where the vehicle and skin are regarded as simple diffusion membranes. By a solution derived from Laplace transforms, the mean residence time MRT and the variance of the residence time VRT in the vehicle are expressed as simple elementary functions of the following five pharmacokinetic parameters characterizing the percutaneous drug absorption: kd, which is defined as the normalized diffusion coefficient of the skin, kc, which is defined as the normalized skin-capillary boundary clearance, the apparent length of diffusion of the skin 1d, the effective length of the vehicle lv, and the diffusion coefficient of the vehicle Dv. All five parameters can be obtained by the methods proposed here. Results of numerical computation indicate that: concentration-distance curves in the vehicle and skin approximate two curves which are simply expressed using trigonometric functions when sufficient time elapses after an ointment application; the most suitable condition for the assumption that the concentration of a drug in the uppermost epidermis can be considered unchanged is the case where the partition coefficient between vehicle and skin is small, and the constancy of drug concentration is even more valid when the effective length of the vehicle is large; and the amount of a drug in the vehicle or skin and the flow rate of the drug from vehicle into skin or from skin into blood becomes linear on a semilogarithmic scale, and the slopes of those lines are small when Dv is small, when the partition coefficient between vehicle and skin is small, when lv is large, or when kc is small. A simple simulation method is also proposed using a biexponential for the concentration-time curve for the skin near the skin-capillary boundary, that is, the flow rate-time curve for drug passing from skin

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

    PubMed

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

    2012-03-01

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

  20. 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.

  1. 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.

  2. 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.

  3. Non-uniform black strings and the critical dimension in the 1/D expansion

    NASA Astrophysics Data System (ADS)

    Suzuki, Ryotaku; Tanabe, Kentaro

    2015-10-01

    Non-uniform black strings (NUBS) are studied by the large D effective theory approach. By solving the near-horizon geometry in the 1 /D expansion, we obtain the effective equation for the deformed horizon up to the next-to-next-to-leading order (NNLO) in 1 /D. We also solve the far-zone geometry by the Newtonian approximation. Matching the near and far zones, the thermodynamic variables are computed in the 1 /D expansion. As the result, the large D analysis gives a critical dimension D * ≃ 13 .5 at which the translation-symmetry-breaking phase transition changes between first and second order. This value of D * agrees perfectly, within the precision of the 1 /D expansion, with the result previously obtained by E. Sorkin through the numerical resolution. We also compare our NNLO results for the thermodynamics of NUBS to earlier numerical calculations, and find good agreement within the expected precision.

  4. Modeling blood flow circulation in intracranial arterial networks: a comparative 3D/1D simulation study.

    PubMed

    Grinberg, L; Cheever, E; Anor, T; Madsen, J R; Karniadakis, G E

    2011-01-01

    We compare results from numerical simulations of pulsatile blood flow in two patient-specific intracranial arterial networks using one-dimensional (1D) and three-dimensional (3D) models. Specifically, we focus on the pressure and flowrate distribution at different segments of the network computed by the two models. Results obtained with 1D and 3D models with rigid walls show good agreement in massflow distribution at tens of arterial junctions and also in pressure drop along the arteries. The 3D simulations with the rigid walls predict higher amplitude of the flowrate and pressure temporal oscillations than the 1D simulations with compliant walls at various segments even for small time-variations in the arterial cross-sectional areas. Sensitivity of the flow and pressure with respect to variation in the elasticity parameters is investigated with the 1D model. PMID:20661645

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

    PubMed

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

    2016-06-28

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

  6. Optimization of a cyclic peptide inhibitor of Ser/Thr phosphatase PPM1D (Wip1).

    PubMed

    Hayashi, Ryo; Tanoue, Kan; Durell, Stewart R; Chatterjee, Deb K; Jenkins, Lisa M Miller; Appella, Daniel H; Appella, Ettore

    2011-05-31

    PPM1D (PP2Cδ or Wip1) was identified as a wild-type p53-induced Ser/Thr phosphatase that accumulates after DNA damage and classified into the PP2C family. It dephosphorylates and inactivates several proteins critical for cellular stress responses, including p38 MAPK, p53, and ATM. Furthermore, PPM1D is amplified and/or overexpressed in a number of human cancers. Thus, inhibition of its activity could constitute an important new strategy for therapeutic intervention to halt the progression of several different cancers. Previously, we reported the development of a cyclic thioether peptide with low micromolar inhibitory activity toward PPM1D. Here, we describe important improvements in the inhibitory activity of this class of cyclic peptides and also present a binding model based upon the results. We found that specific interaction of an aromatic ring at the X1 position and negative charge at the X5 and X6 positions significantly increased the inhibitory activity of the cyclic peptide, with the optimized molecule having a K(i) of 110 nM. To the best of our knowledge, this represents the highest inhibitory activity reported for an inhibitor of PPM1D. We further developed an inhibitor selective for PPM1D over PPM1A with a K(i) of 2.9 μM. Optimization of the cyclic peptide and mutagenesis experiments suggest that a highly basic loop unique to PPM1D is related to substrate specificity. We propose a new model for the catalytic site of PPM1D and inhibition by the cyclic peptides that will be useful both for the subsequent design of PPM1D inhibitors and for identification of new substrates. PMID:21528848

  7. Two-loop effective action of O(N) spin models in 1/D expansion

    NASA Astrophysics Data System (ADS)

    Matsui, T.; Kleinert, H.; Ami, S.

    1984-08-01

    We calculate the two-loop effective action of O(N) spin models on the lattice in a 1/D expansion to order 1/D2. The resulting free energy depends on β = 1/T and the order parameter Φ. It matches the high and low temperature regimes and is quite reliable close to the phase transition where it has a simple Landau expansion.

  8. 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)).

  9. Protective mucosal immunity mediated by epithelial CD1d and IL-10.

    PubMed

    Olszak, Torsten; Neves, Joana F; Dowds, C Marie; Baker, Kristi; Glickman, Jonathan; Davidson, Nicholas O; Lin, Chyuan-Sheng; Jobin, Christian; Brand, Stephan; Sotlar, Karl; Wada, Koichiro; Katayama, Kazufumi; Nakajima, Atsushi; Mizuguchi, Hiroyuki; Kawasaki, Kunito; Nagata, Kazuhiro; Müller, Werner; Snapper, Scott B; Schreiber, Stefan; Kaser, Arthur; Zeissig, Sebastian; Blumberg, Richard S

    2014-05-22

    The mechanisms by which mucosal homeostasis is maintained are of central importance to inflammatory bowel disease. Critical to these processes is the intestinal epithelial cell (IEC), which regulates immune responses at the interface between the commensal microbiota and the host. CD1d presents self and microbial lipid antigens to natural killer T (NKT) cells, which are involved in the pathogenesis of colitis in animal models and human inflammatory bowel disease. As CD1d crosslinking on model IECs results in the production of the important regulatory cytokine interleukin (IL)-10 (ref. 9), decreased epithelial CD1d expression--as observed in inflammatory bowel disease--may contribute substantially to intestinal inflammation. Here we show in mice that whereas bone-marrow-derived CD1d signals contribute to NKT-cell-mediated intestinal inflammation, engagement of epithelial CD1d elicits protective effects through the activation of STAT3 and STAT3-dependent transcription of IL-10, heat shock protein 110 (HSP110; also known as HSP105), and CD1d itself. All of these epithelial elements are critically involved in controlling CD1d-mediated intestinal inflammation. This is demonstrated by severe NKT-cell-mediated colitis upon IEC-specific deletion of IL-10, CD1d, and its critical regulator microsomal triglyceride transfer protein (MTP), as well as deletion of HSP110 in the radioresistant compartment. Our studies thus uncover a novel pathway of IEC-dependent regulation of mucosal homeostasis and highlight a critical role of IL-10 in the intestinal epithelium, with broad implications for diseases such as inflammatory bowel disease. PMID:24717441

  10. Fluorine substitution enhanced photovoltaic performance of a D-A(1)-D-A(2) copolymer.

    PubMed

    Dang, Dongfeng; Chen, Weichao; Yang, Renqiang; Zhu, Weiguo; Mammo, Wendimagegn; Wang, Ergang

    2013-10-18

    A new alternating donor-acceptor (D-A1-D-A2) copolymer containing two electron-deficient moieties, isoindigo and quinoxaline, was synthesized. The photovoltaic performance of this polymer could be improved by incorporating fluorine atoms into the quinoxaline units, resulting in an efficiency of 6.32%. This result highlights the attractive promise of D-A1-D-A2 copolymers for high-performance bulk heterojunction solar cells. PMID:24000353

  11. Atypical natural killer T-cell receptor recognition of CD1d-lipid antigens.

    PubMed

    Le Nours, Jérôme; Praveena, T; Pellicci, Daniel G; Gherardin, Nicholas A; Ross, Fiona J; Lim, Ricky T; Besra, Gurdyal S; Keshipeddy, Santosh; Richardson, Stewart K; Howell, Amy R; Gras, Stephanie; Godfrey, Dale I; Rossjohn, Jamie; Uldrich, Adam P

    2016-01-01

    Crucial to Natural Killer T (NKT) cell function is the interaction between their T-cell receptor (TCR) and CD1d-antigen complex. However, the diversity of the NKT cell repertoire and the ensuing interactions with CD1d-antigen remain unclear. We describe an atypical population of CD1d-α-galactosylceramide (α-GalCer)-reactive human NKT cells that differ markedly from the prototypical TRAV10-TRAJ18-TRBV25-1(+) type I NKT cell repertoire. These cells express a range of TCR α- and β-chains that show differential recognition of glycolipid antigens. Two atypical NKT TCRs (TRAV21-TRAJ8-TRBV7-8 and TRAV12-3-TRAJ27-TRBV6-5) bind orthogonally over the A'-pocket of CD1d, adopting distinct docking modes that contrast with the docking mode of all type I NKT TCR-CD1d-antigen complexes. Moreover, the interactions with α-GalCer differ between the type I and these atypical NKT TCRs. Accordingly, diverse NKT TCR repertoire usage manifests in varied docking strategies and specificities towards CD1d-α-GalCer and related antigens, thus providing far greater scope for diverse glycolipid antigen recognition. PMID:26875526

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

    PubMed

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

    2016-01-01

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

  13. The SLE-associated Pbx1-d isoform acts as a dominant-negative transcriptional regulator

    PubMed Central

    Sengupta, M; Liang, S; Potula, H-HS; Chang, L-J; Morel, L

    2013-01-01

    Pbx1 is a transcription factor involved in multiple cellular processes, including the maintenance of self-renewal of hematopoietic progenitors. We have shown that the CD4 + T-cell expression of a novel splice isoform of Pbx1, Pbx1-d, is associated with lupus susceptibility in the NZM2410 mouse and in lupus patients. The function of Pbx1 in T cells is unknown, but the splicing out of the DNA-binding domain in Pbx1-d predicts a dominant-negative function. In support of this hypothesis, we have shown that Pbx1-d transduction accelerates differentiation of MC3T3-E1 osteoblast pregenitors and mimics the effect of short hairpin RNA silencing of Pbx1. Conversely, Pbx1-d transduction reduced the expression of Sox3, a gene strongly transactivated by Pbx1, and Pbx1-d did not bind the Sox3 promoter. These results constitute a first step towards the understanding on how Pbx1-d contributes to systemic autoimmunity in the NZM2410 mouse model as well as in lupus patients. PMID:22992721

  14. The Temporal Evolution of O(1D) Emission in Ionospheric Modification Experiments

    NASA Astrophysics Data System (ADS)

    Kalogerakis, K. S.; Byler, E. B.

    2009-04-01

    Understanding processes involving atomic oxygen is crucial for the study of energy transfer and transport dynamics in the upper atmosphere. Until recently, the lack of reliable information on the role of O(3P ) collisions in relaxing O(1D) has often led to the assumption that the ionospheric atomic oxygen red line emission decay was controlled by collisions with N2. Laboratory measurements at SRI International have established that the removal rate constants for O(1D) + N2 and O(1D) + O are comparable and therefore O atoms play a major role in the ionospheric O(1D) decay at altitudes between 200 and 300 km. We have previously shown that measuring the O(1D) emission decay following ionospheric modification provides an approach for Remote O-atom Sensing by Ionospheric Excitation (ROSIE). In this report, we present examples of available ionospheric modification data sets from several heating facilities, examine the details of the appearance and decay of the O(1D) emission, and interpret its temporal evolution. This work is supported by the CEDAR Program of the U.S. National Science Foundation (NSF) under grant no. ATM-0737713. The participation of Eleanor B. Byler was made possible by the NSF Research Experiences for Undergraduates Program under grant no. PHY-0649315.

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

    PubMed

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

    2015-07-01

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

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

    PubMed Central

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

    2016-01-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2012-02-01

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

  18. Lie symmetry properties of nonlinear reaction-diffusion equations with gradient-dependent diffusivity

    NASA Astrophysics Data System (ADS)

    Cherniha, Roman; King, John R.; Kovalenko, Sergii

    2016-07-01

    Complete descriptions of the Lie symmetries of a class of nonlinear reaction-diffusion equations with gradient-dependent diffusivity in one and two space dimensions are obtained. A surprisingly rich set of Lie symmetry algebras depending on the form of diffusivity and source (sink) in the equations is derived. It is established that there exists a subclass in 1-D space admitting an infinite-dimensional Lie algebra of invariance so that it is linearisable. A special power-law diffusivity with a fixed exponent, which leads to wider Lie invariance of the equations in question in 2-D space, is also derived. However, it is shown that the diffusion equation without a source term (which often arises in applications and is sometimes called the Perona-Malik equation) possesses no rich variety of Lie symmetries depending on the form of gradient-dependent diffusivity. The results of the Lie symmetry classification for the reduction to lower dimensionality, and a search for exact solutions of the nonlinear 2-D equation with power-law diffusivity, also are included.

  19. A 1-D Cryothermal Model of Ceres’ Megaregolith: Predictions for Surface Vapor Flux, Subsurface Temperatures and Pore Ice Distribution

    NASA Astrophysics Data System (ADS)

    Reynolds, Dylan; Wood, Stephen E.; Bapst, Jonathan; Mehlhaff, Joshua; Griffiths, Stephen G.

    2014-11-01

    We have applied a self-consistent 1-D model for heat diffusion, vapor diffusion, and ice condensation/sublimation, and surface energy balance to investigate our hypothesis for the source of the recently observed water vapor around Ceres [1]. As described in a companion presentation [2], we find that the estimated global flux of 6 kg/s can be produced by steady-state sublimation of subsurface ice driven by the “geothermal” temperature gradient for a heat flux of 1 mW/m2 - the value estimated for a chondritic abundance of heat-producing elements [3,4]. We will present a detailed description of our Ceres cryothermal diffusion model and comparisons with previous models. One key difference is the use of a new physics-based analytic model (‘MaxRTCM’) for calculating the thermal conductivity (Kth) of planetary regolith [5] that has been validated by comparisons to a wide range of laboratory data [6]. MaxRTCM predicts much lower Kth values in the upper regolith than those in previous work [3]. It also accounts for a process first modeled in a study of unstable equatorial ground ice on Mars [7,8], where vapor diffusing up from a receding ice table toward the surface can recondense at shallower depths - eventually forming a steady-state profile of pore ice volume fraction that increases with depth and maintains a constant flux of vapor at all depths [7]. Using MaxRTCM we calculate the corresponding Kth(z) profiles and will present predictions and implications of the resulting temperature profile in the upper few kilometers of Ceres’ megaregolith.References: [1] Küppers et al. (2014), Nature, 505(7484), 525-527. [2] Wood et al., 2014, this meeting. [3] Fanale & Salvail (1989) Icarus 82, 97-110. [4] McCord and Sotin (2005) JGR 110, E05009. [5] Wood (2013) LPSC Abs. 44, 3077. [6] Wood (2014), Icarus, in revision. [7] Mellon et al. (1997), JGR, 102, 19357-69. [8] Clifford (1993), JGR, 98, 10973-11016.

  20. Substrate specificity and inhibitor analyses of human steroid 5β-reductase (AKR1D1)

    PubMed Central

    Chen, Mo; Drury, Jason E.; Penning, Trevor M.

    2011-01-01

    Human steroid 5β-reductase (Aldo-keto Reductase 1D1) catalyzes the stereospecific NADPH-dependent reduction of the C4-C5 double bond of Δ4-ketosteroids to yield an A/B cis-ring junction. This cis-configuration is crucial for bile acid biosynthesis and plays important roles in steroid metabolism. The biochemical properties of the enzyme have not been thoroughly studied and conflicting data have been reported, partially due to the lack of highly homogeneous protein. In the present study, we systematically determined the substrate specificity of homogeneous human recombinant AKR1D1 using C18, C19, C21, and C27 Δ4-ketosteroids and assessed the pH-rate dependence of the enzyme. Our results show that AKR1D1 proficiently reduced all the steroids tested at physiological pH, indicating AKR1D1 is the only enzyme necessary for all the 5β-steroid metabolite present in humans. Substrate inhibition was observed with C18 to C21 steroids provided that the side-chain at C17 was unsubstituted. This structure activity relationship can be explained by the existence of a small alternative substrate binding pocket revealed by the AKR1D1 crystal structure. Non-steroidal anti-inflammatory drugs which are potent inhibitors of the related AKR1C enzymes do not inhibit AKR1D1 by contrast chenodeoxycholate and ursodeoxycholate were found to be potent non-competitive inhibitors suggesting that bile-acids may regulate their own synthesis at the level of AKR1D1 inhibition. PMID:21255593

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

    SciTech Connect

    Miller, D S

    2000-08-21

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

  2. Computational simulations of vorticity enhanced diffusion

    NASA Astrophysics Data System (ADS)

    Vold, Erik L.

    1999-11-01

    Computer simulations are used to investigate a phenomenon of vorticity enhanced diffusion (VED), a net transport and mixing of a passive scalar across a prescribed vortex flow field driven by a background gradient in the scalar quantity. The central issue under study here is the increase in scalar flux down the gradient and across the vortex field. The numerical scheme uses cylindrical coordinates centered with the vortex flow which allows an exact advective solution and 1D or 2D diffusion using simple numerical methods. In the results, the ratio of transport across a localized vortex region in the presence of the vortex flow over that expected for diffusion alone is evaluated as a measure of VED. This ratio is seen to increase dramatically while the absolute flux across the vortex decreases slowly as the diffusion coefficient is decreased. Similar results are found and compared for varying diffusion coefficient, D, or vortex rotation time, τv, for a constant background gradient in the transported scalar vs an interface in the transported quantity, and for vortex flow fields constant in time vs flow which evolves in time from an initial state and with a Schmidt number of order unity. A simple analysis shows that for a small diffusion coefficient, the flux ratio measure of VED scales as the vortex radius over the thickness for mass diffusion in a viscous shear layer within the vortex characterized by (Dτv)1/2. The phenomenon is linear as investigated here and suggests that a significant enhancement of mixing in fluids may be a relatively simple linear process. Discussion touches on how this vorticity enhanced diffusion may be related to mixing in nonlinear turbulent flows.

  3. CD1d-restricted antigen presentation by Vγ9Vδ2-T cells requires trogocytosis.

    PubMed

    Schneiders, Famke L; Prodöhl, Jan; Ruben, Jurjen M; O'Toole, Tom; Scheper, Rik J; Bonneville, Marc; Scotet, Emmanuel; Verheul, Henk M W; de Gruijl, Tanja D; van der Vliet, Hans J

    2014-08-01

    CD1d-restricted invariant natural killer T cells (iNKT) constitute an important immunoregulatory T-cell subset that can be activated by the synthetic glycolipid α-galactosylceramide (α-GalCer) and play a dominant role in antitumor immunity. Clinical trials with α-GalCer-pulsed monocyte-derived dendritic cells (moDC) have shown anecdotal antitumor activity in advanced cancer. It was reported that phosphoantigen (pAg)-activated Vγ9Vδ2-T cells can acquire characteristics of professional antigen-presenting cells (APC). Considering the clinical immunotherapeutic applications, Vγ9Vδ2-T APC can offer important advantages over moDC, potentially constituting an attractive novel APC platform. Here, we demonstrate that Vγ9Vδ2-T APC can present antigens to iNKT. However, this does not result from de novo synthesis of CD1d by Vγ9Vδ2-T, but critically depends on trogocytosis of CD1d-containing membrane fragments from pAg-expressing cells. CD1d-expressing Vγ9Vδ2-T cells were able to activate iNKT in a CD1d-restricted and α-GalCer-dependent fashion. Although α-GalCer-loaded moDC outperformed Vγ9Vδ2-T APC on a per cell basis, Vγ9Vδ2-T APC possess unique features with respect to clinical immunotherapeutic application that make them an interesting platform for consideration in future clinical trials. PMID:24934445

  4. Possible Dimensional Crossover to 1D of ^3He Fluid in Nanochannels Observed in Susceptibilities

    NASA Astrophysics Data System (ADS)

    Matsushita, Taku; Kurebayashi, Katsuya; Shibatsuji, Ryosuke; Hieda, Mitsunori; Wada, Nobuo

    2016-05-01

    Dimensional crossover to the one-dimensional (1D) state from higher dimensions has been studied for dilute ^3He fluid adsorbed in 2.4 nm ^4He-preplated nanochannels, by susceptibility measurements down to 70 mK using 4.29 MHz nuclear magnetic resonance. In nanochannels, since energy states of ^3He motion perpendicular to the channel axis are discrete, a genuine 1D ^3He fluid is expected when the Fermi energy is less than the first excitation Δ _{01} for azimuthal motion. The susceptibilities χ above 0.3 K show the Curie-law susceptibilities independent of the ^3He density, which are characteristic of nondegenerate fluid in higher dimensions. With decreasing the temperature, a significant reduction of χ T was observed from about 0.3 K for all ^3He densities. It is considered to be due to the dimensional crossover below Δ _{01}˜ 0.5 K to the 1D ^3He state in the semi-degenerate regime above the Fermi temperature. In the 1D state at lower temperatures, T-independent χ were observed for ^3He of 0.019 layers below 0.1 K. It suggests that the 1D ^3He fluid enters the quantum degenerate regime.

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

    PubMed

    Moore, James R; Adler, Fred

    2016-03-01

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

  6. 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

    2015-10-01

    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. PMID:26324759

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

    PubMed

    Zhu, Ying; Bai, Hongcun; Huang, Yuanhe

    2016-02-01

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

  8. Deconvolution of Complex 1D NMR Spectra Using Objective Model Selection.

    PubMed

    Hughes, Travis S; Wilson, Henry D; de Vera, Ian Mitchelle S; Kojetin, Douglas J

    2015-01-01

    Fluorine (19F) NMR has emerged as a useful tool for characterization of slow dynamics in 19F-labeled proteins. One-dimensional (1D) 19F NMR spectra of proteins can be broad, irregular and complex, due to exchange of probe nuclei between distinct electrostatic environments; and therefore cannot be deconvoluted and analyzed in an objective way using currently available software. We have developed a Python-based deconvolution program, decon1d, which uses Bayesian information criteria (BIC) to objectively determine which model (number of peaks) would most likely produce the experimentally obtained data. The method also allows for fitting of intermediate exchange spectra, which is not supported by current software in the absence of a specific kinetic model. In current methods, determination of the deconvolution model best supported by the data is done manually through comparison of residual error values, which can be time consuming and requires model selection by the user. In contrast, the BIC method used by decond1d provides a quantitative method for model comparison that penalizes for model complexity helping to prevent over-fitting of the data and allows identification of the most parsimonious model. The decon1d program is freely available as a downloadable Python script at the project website (https://github.com/hughests/decon1d/). PMID:26241959

  9. Alterations in cellular metabolism modulate CD1d-mediated NKT-cell responses.

    PubMed

    Webb, Tonya J; Carey, Gregory B; East, James E; Sun, Wenji; Bollino, Dominique R; Kimball, Amy S; Brutkiewicz, Randy R

    2016-08-01

    Natural killer T (NKT) cells play a critical role in the host's innate immune response. CD1d-mediated presentation of glycolipid antigens to NKT cells has been established; however, the mechanisms by which NKT cells recognize infected or cancerous cells remain unclear. 5(')-AMP activated protein kinase (AMPK) is a master regulator of lipogenic pathways. We hypothesized that activation of AMPK during infection and malignancy could alter the repertoire of antigens presented by CD1d and serve as a danger signal to NKT cells. In this study, we examined the effect of alterations in metabolism on CD1d-mediated antigen presentation to NKT cells and found that an infection with lymphocytic choriomeningitis virus rapidly increased CD1d-mediated antigen presentation. Hypoxia inducible factors (HIF) enhance T-cell effector functions during infection, therefore antigen presenting cells pretreated with pharmacological agents that inhibit glycolysis, induce HIF and activate AMPK were assessed for their ability to induce NKT-cell responses. Pretreatment with 2-deoxyglucose, cobalt chloride, AICAR and metformin significantly enhanced CD1d-mediated NKT-cell activation. In addition, NKT cells preferentially respond to malignant B cells and B-cell lymphomas express HIF-1α. These data suggest that targeting cellular metabolism may serve as a novel means of inducing innate immune responses. PMID:27297969

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

    SciTech Connect

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

    2008-09-15

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

  11. Observation of single-file diffusion in a MOF.

    PubMed

    Jobic, H

    2016-06-29

    The translational and rotational dynamics of neopentane adsorbed in the one-dimensional channels of MIL-47(V) has been studied by quasi-elastic neutron scattering. The rotational motion of neopentane is well-described by the rotational diffusion model, with a correlation time of 41 ps at 300 K. The translational motion of the molecule has been fitted by several models: isotropic diffusion, normal 1D and single-file diffusion. It is found that the observed line shapes can only be reproduced by the single-file diffusion model. The single-file mobility factor, F, is (8 ± 1) × 10(-14) m(2) s(-1/2) at 300 K. This is the first observation of this unusual diffusion behaviour in a MOF. PMID:26932296

  12. Phosphorus Doping of Polycrystalline CdTe by Diffusion

    SciTech Connect

    Colegrove, Eric; Albin, David S.; Guthrey, Harvey; Harvey, Steve; Burst, James; Moutinho, Helio; Farrell, Stuart; Al-Jassim, Mowafak; Metzger, Wyatt K.

    2015-06-14

    Phosphorus diffusion in single crystal and polycrystalline CdTe material is explored using various methods. Dynamic secondary ion mass spectroscopy (SIMS) is used to determine 1D P diffusion profiles. A 2D diffusion model is used to determine the expected cross-sectional distribution of P in CdTe after diffusion anneals. Time of flight SIMS and cross-sectional cathodoluminescence corroborates expected P distributions. Devices fabricated with diffused P exhibit hole concentrations up to low 1015 cm-3, however a subsequent activation anneal enabled hole concentrations greater than 1016 cm-3. CdCl2 treatments and Cu based contacts were also explored in conjunction with the P doping process.

  13. 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.

  14. Protein folding trajectories can be described quantitatively by one-dimensional diffusion over measured energy landscapes

    NASA Astrophysics Data System (ADS)

    Neupane, Krishna; Manuel, Ajay P.; Woodside, Michael T.

    2016-07-01

    Protein folding features a diffusive search over a multidimensional energy landscape in conformational space for the minimum-energy structure. Experiments, however, are usually interpreted in terms of a one-dimensional (1D) projection of the full landscape onto a practical reaction coordinate. Although simulations have shown that folding kinetics can be described well by diffusion over a 1D projection, 1D approximations have not yet been fully validated experimentally. We used folding trajectories of single molecules held under tension in optical tweezers to compare the conditional probability of being on a transition path, calculated from the trajectory, with the prediction for ideal 1D diffusion over the measured 1D landscape, calculated from committor statistics. We found good agreement for the protein PrP (refs ,) and for one of the structural transitions in a leucine-zipper coiled-coil, but not for a second transition in the coiled-coil, owing to poor reaction-coordinate quality. These results show that 1D descriptions of folding can indeed be good, even for complex tertiary structures. More fundamentally, they also provide a fully experimental validation of the basic physical picture of folding as diffusion over a landscape.

  15. 1D cadmium(II) thiocyanate systems: Synthesis and characterization of three new polymeric 1D cadmium(II) thiocyanato complexes

    NASA Astrophysics Data System (ADS)

    Saber, Mohamed R.; Abu-Youssef, Morsy A. M.; Goher, Mohamed A. S.; Sabra, Berry A.; Hafez, Afaf K.; Badr, Ahmed M.-A.; Mautner, Franz A.

    2012-01-01

    Three new cadmium(II) thiocyanato complexes, [{Cd(NCS) 2(val)}·H 2O] n1, [Cd(NCS) 2(3-ampy) 2] n2, and [Cd(NCS) 2(pyrazolinone)] n3, (val = D, L-valine, 3-ampy = 3-aminopyridine and pyrazolinone = 3-methyl-1-phenyl-2-pyrazolin-5-one) have been synthesized and structurally characterized. The X-ray structure analysis revealed di-μ-N,S thiocyanato bridges connecting cadmium centers in a 1D chain with the co-ligand blocking the remaining coordination sites. The structure of complex 1 features six coordinate Cd(II) centers, each cadmium is surrounded by two N atoms and two S atoms from two bridging N,S-thiocyanato groups giving rise to a zigzag 1D chain and two oxygen atoms of the alternating chelating μ-O,O'-valine that coordinates as zwitterionic terminal amino acid. The structure of complex 2 consists of octahedral Cd(II) centers, connected by di-μ-N,S-bridging NCS groups, thus forming a 1D chain system along the [1 0 1] direction. The amino-groups are forming one intra-chain N sbnd H⋯N hydrogen bond and one interchain N sbnd H⋯N hydrogen bond to N-atoms of adjacent chains. The structure of 3 reveals di-μ-N,S-NCS doubly bridged unusual penta-coordinated cadmium centers with the alternating monodentate pyrazolinone ligand blocking the fifth coordination site. IR spectra and thermal properties of complexes are reported.

  16. Operational fog monitoring using FY-1D remotely sensed data in China

    NASA Astrophysics Data System (ADS)

    Qian, Yonglan; Zhang, Guoping; Wang, Maoxin

    2006-12-01

    Fog is a disaster that troubles the people life especially the traffic safety and air quality. NOAA and EOS/MOSDIS data can both be used to monitor the fog disaster, but FY-1D data is the best in China for its timely acquirement that covers the local region. So fog monitoring using FY-1D in China can offer timely fog disaster information for traffic safety forecast and further weather trend analyses. Fog monitoring mainly uses visible and infrared bands which are not very good for fog mapping, however. The paper analyzed the image spectral properties of fog and low stratus to choose the best band combination for optimal fog mapping. The paper proposed the method of using FY-1D data to monitor daytime fog disaster in China.

  17. Spin Excitations and Phonon Anomaly in Quasi-1D Spiral Magneti CuBr2

    NASA Astrophysics Data System (ADS)

    Li, Yuan; Wang, Chong; Yu, Daiwei; Wang, Lichen; Wang, Fa; Iida, Kazuki; Kamazawa, Kazuya; Wakimoto, Shuichi

    CuBr2 can be considered as a model quasi-one-dimensional (quasi-1D) spin-1/2 magnet, in which the frustrating ferromagnetic nearest-neighbor and antiferromagnetic next-nearest-neighbor exchange interactions give rise to a cycloidal magnetic order below TN = 73 K. The removal of inversion symmetry by the magnetic order also makes the material a type-II multiferroic system with a remarkably simple crystal structure. Using time-of-flight inelastic neutron scattering spectroscopy, we have determined the spin-wave as well as phonon spectra throughout the entire Brillouin zone. The spin-wave spectrum exhibits pronounced anisotropy and magnon damping, consistent with the material's quasi-1D nature and the non-colinear spin structure. The phonon spectrum exhibits dramatic discontinuities in the dispersion across the quasi-1D magnetic wave vector, indicative of strong magnetoelastic coupling and possibly of a spin-orbital texture that comes along with the spin correlations.

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

    PubMed Central

    2014-01-01

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

  19. 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.

  20. Microfabricated diffusion source

    DOEpatents

    Oborny, Michael C.; Frye-Mason, Gregory C.; Manginell, Ronald P.

    2008-07-15

    A microfabricated diffusion source to provide for a controlled diffusion rate of a vapor comprises a porous reservoir formed in a substrate that can be filled with a liquid, a headspace cavity for evaporation of the vapor therein, a diffusion channel to provide a controlled diffusion of the vapor, and an outlet to release the vapor into a gas stream. The microfabricated diffusion source can provide a calibration standard for a microanalytical system. The microanalytical system with an integral diffusion source can be fabricated with microelectromechanical systems technologies.

  1. Viscous shear heating instabilities in a 1-D viscoelastic shear zone

    NASA Astrophysics Data System (ADS)

    Homburg, J. M.; Coon, E. T.; Spiegelman, M.; Kelemen, P. B.; Hirth, G.

    2010-12-01

    Viscous shear instabilities may provide a possible mechanism for some intermediate depth earthquakes where high confining pressure makes it difficult to achieve frictional failure. While many studies have explored the feedback between temperature-dependent strain rate and strain-rate dependent shear heating (e.g. Braeck and Podladchikov, 2007), most have used thermal anomalies to initiate a shear instability or have imposed a low viscosity region in their model domain (John et al., 2009). By contrast, Kelemen and Hirth (2007) relied on an initial grain size contrast between a predetermined fine-grained shear zone and coarse grained host rock to initiate an instability. This choice is supported by observations of numerous fine grained ductile shear zones in shallow mantle massifs as well as the possibility that annealed fine grained fault gouge, formed at oceanic transforms, subduction related thrusts and ‘outer rise’ faults, could be carried below the brittle/ductile transition by subduction. Improving upon the work of Kelemen and Hirth (2007), we have developed a 1-D numerical model that describes the behavior of a Maxwell viscoelastic body with the rheology of dry olivine being driven at a constant velocity at its boundary. We include diffusion and dislocation creep, dislocation accommodated grain boundary sliding, and low-temperature plasticity (Peierls mechanism). Initial results suggest that including low-temperature plasticity inhibits the ability of the system to undergo an instability, similar to the results of Kameyama et al. (1999). This is due to increased deformation in the background allowing more shear heating to take place, and thus softening the system prior to reaching the peak stress. However if the applied strain rate is high enough (e.g. greater than 0.5 x 10-11 s-1 for a domain size of 2 km, an 8 m wide shear zone, a background grain size of 1 mm, a shear zone grain size of 150 μm, and an initial temperature of 650°C) dramatic

  2. Analytic expressions for ULF wave radiation belt radial diffusion coefficients

    PubMed Central

    Ozeke, Louis G; Mann, Ian R; Murphy, Kyle R; Jonathan Rae, I; Milling, David K

    2014-01-01

    We present analytic expressions for ULF wave-derived radiation belt radial diffusion coefficients, as a function of L and Kp, which can easily be incorporated into global radiation belt transport models. The diffusion coefficients are derived from statistical representations of ULF wave power, electric field power mapped from ground magnetometer data, and compressional magnetic field power from in situ measurements. We show that the overall electric and magnetic diffusion coefficients are to a good approximation both independent of energy. We present example 1-D radial diffusion results from simulations driven by CRRES-observed time-dependent energy spectra at the outer boundary, under the action of radial diffusion driven by the new ULF wave radial diffusion coefficients and with empirical chorus wave loss terms (as a function of energy, Kp and L). There is excellent agreement between the differential flux produced by the 1-D, Kp-driven, radial diffusion model and CRRES observations of differential electron flux at 0.976 MeV—even though the model does not include the effects of local internal acceleration sources. Our results highlight not only the importance of correct specification of radial diffusion coefficients for developing accurate models but also show significant promise for belt specification based on relatively simple models driven by solar wind parameters such as solar wind speed or geomagnetic indices such as Kp. Key Points Analytic expressions for the radial diffusion coefficients are presented The coefficients do not dependent on energy or wave m value The electric field diffusion coefficient dominates over the magnetic PMID:26167440

  3. Carboxyl terminus-truncated α1D-adrenoceptors inhibit the ERK pathway.

    PubMed

    Alfonzo-Méndez, Marco A; Castillo-Badillo, Jean A; Romero-Ávila, M Teresa; Rivera, Richard; Chun, Jerold; García-Sáinz, J Adolfo

    2016-08-01

    Human α1D-adrenoceptors are G protein-coupled receptors that mediate adrenaline/noradrenaline actions. There is a growing interest in identifying regulatory domains in these receptors and determining how they function. In this work, we show that the absence of the human α1D-adrenoceptor carboxyl tail results in altered ERK (extracellular signal-regulated kinase) and p38 phosphorylation states. Amino terminus-truncated and both amino and carboxyl termini-truncated α1D-adrenoceptors were transfected into Rat-1, HEK293, and B103 cells, and changes in the phosphorylation state of extracellular signal-regulated kinase was assessed using biochemical and biophysical approaches. The phosphorylation state of other protein kinases (p38, MEK1, and Raf-1) was also studied. Noradrenaline-induced ERK phosphorylation in Rat-1 fibroblasts expressing amino termini-truncated α1D-adrenoceptors. However, in cells expressing receptors with both amino and carboxyl termini truncations, noradrenaline-induced activation was abrogated. Interestingly, ERK phosphorylation that normally occurs through activation of endogenous G protein-coupled receptors, EGF receptors, and protein kinase C, was also decreased, suggesting that downstream steps in the mitogen-activated protein kinase pathway were affected. A similar effect was observed in B103 cells but not in HEK 293 cells. Phosphorylation of Raf-1 and MEK1 was also diminished in Rat-1 fibroblasts expressing amino- and carboxyl-truncated α1D-adrenoceptors. Our data indicate that expression of carboxyl terminus-truncated α1D-adrenoceptors alters ERK and p38 phosphorylation state. PMID:27146292

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

    NASA Astrophysics Data System (ADS)

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

    2016-07-01

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

  5. Modeling of general 1-D periodic leaky-wave antennas in layered media using EIGER.

    SciTech Connect

    Wilton, Donald R.; Basilio, Lorena I.; Celepcikay, Ferhat T.; Johnson, William Arthur; Baccarelli, Paolo; Valerio, Guido; Paulotto, Simone; Langston, William L.; Jackson, David R.

    2010-09-01

    This paper presents a mixed-potential integral-equation formulation for analyzing 1-D periodic leaky-wave antennas in layered media. The structures are periodic in one dimension and finite in the other two dimensions. The unit cell consists of an arbitrary-shaped metallic/dielectric structure. The formulation has been implemented in the EIGER{trademark} code in order to obtain the real and complex propagation wavenumbers of the bound and leaky modes of such structures. Validation results presented here include a 1-D periodic planar leaky-wave antenna and a fully 3-D waveguide test case.

  6. Modeling of general 1-D periodic leaky-wave antennas in layered media with EIGER.

    SciTech Connect

    Wilton, Donald R.; Basilio, Lorena I.; Celepcikay, F. T.; Johnson, William Arthur; Baccarelli, Paolo; Valerio, G.; Paulotto, Simone; Langston, William L.; Jackson, David R.

    2010-06-01

    This paper presents a mixed-potential integral-equation formulation for analyzing 1-D periodic leaky-wave antennas in layered media. The structures are periodic in one dimension and finite in the other two dimensions. The unit cell consists of an arbitrary-shaped metallic/dielectric structure. The formulation has been implemented in the EIGER{trademark} code in order to obtain the real and complex propagation wavenumbers of the bound and leaky modes of such structures. Validation results presented here include a 1-D periodic planar leaky-wave antenna and a fully 3-D waveguide test case.

  7. 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.

  8. 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.

  9. Lattice study of (D¯ 1D*)± near-threshold scattering

    NASA Astrophysics Data System (ADS)

    Chen, Ting; Chen, Ying; Gong, Ming; Lei, Yu-Hong; Li, Ning; Liu, Chuan; Liu, Yu-Bin; Liu, Zhao-Feng; Ma, Jian-Ping; Wang, Zhan-Lin; Zhang, Jian-Bo; Clqcd Collaboration

    2016-06-01

    In this exploratory lattice study, low-energy near threshold scattering of the (D¯1D*)± meson system is analyzed using lattice QCD with Nf=2 twisted mass fermion configurations. Both s-wave (JP=0-) and p-wave (JP=1+) channels are investigated. It is found that the interaction between the two charmed mesons is attractive near the threshold in both channels. This calculation provides some hints in the searching of resonances or bound states around the threshold of (D¯1D*)± system.

  10. Diffusion on spatial network

    NASA Astrophysics Data System (ADS)

    Hui, Zi; Tang, Xiaoyue; Li, Wei; Greneche, Jean-Marc; Wang, Qiuping A.

    2015-04-01

    In this work, we study the problem of diffusing a product (idea, opinion, disease etc.) among agents on spatial network. The network is constructed by random addition of nodes on the planar. The probability for a previous node to be connected to the new one is inversely proportional to their spatial distance to the power of α. The diffusion rate between two connected nodes is inversely proportional to their spatial distance to the power of β as well. Inspired from the Fick's first law, we introduce the diffusion coefficient to measure the diffusion ability of the spatial network. Using both theoretical analysis and Monte Carlo simulation, we get the fact that the diffusion coefficient always decreases with the increasing of parameter α and β, and the diffusion sub-coefficient follows the power-law of the spatial distance with exponent equals to -α-β+2. Since both short-range diffusion and long-range diffusion exist, we use anomalous diffusion method in diffusion process. We get the fact that the slope index δ in anomalous diffusion is always smaller that 1. The diffusion process in our model is sub-diffusion.

  11. Interpretation of MSL REMS data using 1D coupled heat and water vapor transport model of Mars subsurface

    NASA Astrophysics Data System (ADS)

    Gloesener, Elodie; Karatekin, Özgür; Dehant, Véronique

    2016-04-01

    MSL Rover Environmental Monitoring Station (REMS) performed high-resolution measurements of temperature and relative humidity during more than one Martian year. In this work, a 1D subsurface model is used to study water vapor exchange between the atmosphere and the subsurface at Gale crater using REMS data. The thermal model used includes several layers of varying thickness with depth and properties that can be changed to correspond to those of Martian rocks at locations studied. It also includes the transport of water vapor through porous Martian regolith and the different phases considered are vapor, ice and adsorbed H2O. The total mass flux is given by the sum of diffusive and advective transport. The role of an adsorbing regolith on water transfer as well as the range of parameters with significant effect on water transport in Martian conditions are investigated. In addition, kinetics of the adsorption process is considered to examine its influence on the water vapor exchange between the subsurface and the atmosphere.

  12. A 2D/1D coupling neutron transport method based on the matrix MOC and NEM methods

    SciTech Connect

    Zhang, H.; Zheng, Y.; Wu, H.; Cao, L.

    2013-07-01

    A new 2D/1D coupling method based on the matrix MOC method (MMOC) and nodal expansion method (NEM) is proposed for solving the three-dimensional heterogeneous neutron transport problem. The MMOC method, used for radial two-dimensional calculation, constructs a response matrix between source and flux with only one sweep and then solves the linear system by using the restarted GMRES algorithm instead of the traditional trajectory sweeping process during within-group iteration for angular flux update. Long characteristics are generated by using the customization of commercial software AutoCAD. A one-dimensional diffusion calculation is carried out in the axial direction by employing the NEM method. The 2D and ID solutions are coupled through the transverse leakage items. The 3D CMFD method is used to ensure the global neutron balance and adjust the different convergence properties of the radial and axial solvers. A computational code is developed based on these theories. Two benchmarks are calculated to verify the coupling method and the code. It is observed that the corresponding numerical results agree well with references, which indicates that the new method is capable of solving the 3D heterogeneous neutron transport problem directly. (authors)

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

    NASA Astrophysics Data System (ADS)

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

    2015-09-01

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

  14. UPDATING APPLIED DIFFUSION MODELS

    EPA Science Inventory

    Most diffusion models currently used in air quality applications are substantially out of date with understanding of turbulence and diffusion in the planetary boundary layer. Under a Cooperative Agreement with the Environmental Protection Agency, the American Meteorological Socie...

  15. Diffusion bonding aeroengine components

    NASA Astrophysics Data System (ADS)

    Fitzpatrick, G. A.; Broughton, T.

    1988-10-01

    The use of diffusion bonding processes at Rolls-Royce for the manufacture of titanium-alloy aircraft engine components and structures is described. A liquid-phase diffusion bonding process called activated diffusion bonding has been developed for the manufacture of the hollow titanium wide chord fan blade. In addition, solid-state diffusion bonding is being used in the manufacture of hollow vane/blade airfoil constructions mainly in conjunction with superplastic forming and hot forming techniques.

  16. Investigating axial diffusion in cylindrical pores using confocal single-particle fluorescence correlation spectroscopy.

    PubMed

    Chen, Fang; Neupane, Bhanu; Li, Peiyuan; Su, Wei; Wang, Gufeng

    2016-08-01

    We explored the feasibility of using confocal fluorescence correlation spectroscopy to study small nanoparticle diffusion in hundred-nanometer-sized cylindrical pores. By modeling single particle diffusion in tube-like confined three-dimensional space aligned parallel to the confocal optical axis, we showed that two diffusion dynamics can be observed in both original intensity traces and the autocorrelation functions (ACFs): the confined two-dimensional lateral diffusion and the unconfined one-dimensional (1D) axial diffusion. The separation of the axial and confined lateral diffusion dynamics provides an opportunity to study diffusions in different dimensions separately. We further experimentally studied 45 nm carboxylated polystyrene particles diffusing in 300 nm alumina pores. The experimental data showed consistency with the simulation. To extract the accurate axial diffusion coefficient, we found that a 1D diffusion model with a Lorentzian axial collection profile needs to be used to analyze the experimental ACFs. The diffusion of the 45 nm nanoparticles in polyethyleneglycol-passivated 300 nm pores slowed down by a factor of ∼2, which can be satisfactorily explained by hydrodynamic frictions. PMID:27196052

  17. Reduce Confusion about Diffusion.

    ERIC Educational Resources Information Center

    Hebrank, Mary R.

    1997-01-01

    Presents activities that allow students to explore the fundamental but poorly understood concept of diffusion by appealing to their kinesthetic senses first, then challenging their analytical skills as they try to deduce the mathematical principle involved. Presents a computer simulation of diffusion and discusses diffusion's limitations and…

  18. Diffusion of uranium hexafluoride

    NASA Astrophysics Data System (ADS)

    Winkelmann, J.

    This document is part of Subvolume A `Gases in Gases, Liquids and their Mixtures' of Volume 15 `Diffusion in Gases, Liquids and Electrolytes' of Landolt-Börnstein Group IV `Physical Chemistry'. It is part of the chapter of the chapter `Diffusion in Pure Gases' and contains data on diffusion of uranium hexafluoride

  19. Diffusion Strategy Guide.

    ERIC Educational Resources Information Center

    McCutcheon, James R.; Sanders, John R.

    A methodology is presented for planning and managing the spread of educational innovations. The first portion of the guide develops a theoretical framework for diffusion which summarizes and capitalizes on the latest marketing and on the latest marketing and diffusion research findings. Major stages in the diffusion paradigm discussed include…

  20. Handbook on atmospheric diffusion

    SciTech Connect

    Hanna, S.R.; Briggs, G.A.; Hosker, R.P. Jr.

    1982-01-01

    Basic meteorological concepts are covered as well as plume rise, source effects, and diffusion models. Chapters are included on cooling tower plumes and urban diffusion. Suggestions are given for calculating diffusion in special situations, such as for instantaneous releases over complex terrain, over long distances, and during times when chemical reactions or dry or wet deposition are important. (PSB)

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

    NASA Astrophysics Data System (ADS)

    Huang, Hung Ji; Liu, Bo-Heng

    2015-12-01

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

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

    PubMed

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

    2016-05-01

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

  3. 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.

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

    NASA Technical Reports Server (NTRS)

    Morris, Christopher I.

    2002-01-01

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

  5. Canonical decomposition of magnetotelluric responses: Experiment on 1D anisotropic structures

    NASA Astrophysics Data System (ADS)

    Guo, Ze-qiu; Wei, Wen-bo; Ye, Gao-feng; Jin, Sheng; Jing, Jian-en

    2015-08-01

    Horizontal electrical heterogeneity of subsurface earth is mostly originated from structural complexity and electrical anisotropy, and local near-surface electrical heterogeneity will severely distort regional electromagnetic responses. Conventional distortion analyses for magnetotelluric soundings are primarily physical decomposition methods with respect to isotropic models, which mostly presume that the geoelectric distribution of geological structures is of local and regional patterns represented by 3D/2D models. Due to the widespread anisotropy of earth media, the confusion between 1D anisotropic responses and 2D isotropic responses, and the defects of physical decomposition methods, we propose to conduct modeling experiments with canonical decomposition in terms of 1D layered anisotropic models, and the method is one of the mathematical decomposition methods based on eigenstate analyses differentiated from distortion analyses, which can be used to recover electrical information such as strike directions, and maximum and minimum conductivity. We tested this method with numerical simulation experiments on several 1D synthetic models, which turned out that canonical decomposition is quite effective to reveal geological anisotropic information. Finally, for the background of anisotropy from previous study by geological and seismological methods, canonical decomposition is applied to real data acquired in North China Craton for 1D anisotropy analyses, and the result shows that, with effective modeling and cautious interpretation, canonical decomposition could be another good method to detect anisotropy of geological media.

  6. 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...

  7. 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. PMID:25259484

  8. 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.

  9. 1. D Street (south) facade (short side) and 9th Street ...

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

    1. D Street (south) facade (short side) and 9th Street (west) facade (long side). North of the D Street facade is the Edward Abner Building (413-415 9th Street) and north of it is the Ferree Building (417 9th Street). - PMI Parking Garage, 403-407 Ninth Street, Northwest, Washington, District of Columbia, DC

  10. 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

    2016-03-01

    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. PMID:26868599