Volumetric Flow Measurement Using an Implantable CMUT Array.
Mengli Wang; Jingkuang Chen
2011-06-01
This paper describes volumetric-flow velocity measurement using an implantable capacitive micromachined ultrasonic transducer (CMUT) array. The array is comprised of multiple-concentric CMUT rings for ultrasound transmission and an outmost annular CMUT array for ultrasound reception. Microelectromechanical-system (MEMS) fabrication technology allows reception CMUT on this flowmeter to be implemented with a different membrane thickness and gap height than that of transmission CMUTs, optimizing the performance of these two different kinds of devices. The silicon substrate of this 2-mm-diameter CMUT ring array was bulk micromachined to approximately 80 to 100 μm thick, minimizing tissue disruption. The blood-flow velocity was detected using pulse ultrasound Doppler by comparing the demodulated echo ultrasound with the incident ultrasound. The demodulated ultrasound signal was sampled by a pulse delayed in time domain from the transmitted burst, which corresponds to detecting the signal at a specific distance. The flow tube/vessel diameter was detected through the time-flight delay difference from near and far wall reflections, which was measured from the ultrasound pulse echo. The angle between the ultrasound beam and the flow was found by using the cross-correlation from consecutive ultrasound echoes. Artificial blood flowing through three different polymer tubes was experimented with, while keeping the same volumetric flow rate. The discrepancy in flow measurement results between this CMUT meter and a calibrated laser Doppler flowmeter is less than 5%. PMID:23851472
A nonlinear lumped model for ultrasound systems using CMUT arrays.
Satir, Sarp; Degertekin, F Levent
2015-10-01
We present a nonlinear lumped model that predicts the electrical input-output behavior of an ultrasonic system using CMUTs with arbitrary array/membrane/electrode geometry in different transmit-receive configurations and drive signals. The receive-only operation, where the electrical output signal of the CMUT array in response to incident pressure field is calculated, is included by modifying the boundary elementbased vibroacoustic formulation for a CMUT array in rigid baffle. Along with the accurate large signal transmit model, this formulation covers pitch-catch and pulse-echo operation when transmit and receive signals can be separated in time. In cases when this separation is not valid, such as CMUTs used in continuous wave transmit-receive mode, pulse-echo mode with a nearby hard or soft wall or in a bounded space such as in a microfluidic channel, an efficient formulation based on the method of images is used. Some of these particular applications and the overall modeling approach have been validated through comparison with finite element analysis on specific examples including CMUTs with multiple electrodes. To further demonstrate the capability of the model for imaging applications, the two-way response of a partial dual-ring intravascular ultrasound array is simulated using a parallel computing cluster, where the output currents of individual array elements are calculated for given input pulse and compared with experimental results. With its versatility, the presented model can be a useful tool for rapid iterative CMUT-based system design and simulation for a broad range of ultrasonic applications. PMID:26470049
2-D Row-Column CMUT Arrays with an Open-Grid Support Structure
DEFF Research Database (Denmark)
Christiansen, Thomas Lehrmann; Dahl-Petersen, Christian; Jensen, Jørgen Arendt;
2013-01-01
Fabrication and characterization of 64 + 64 2-D row-column addressed CMUT arrays with 250 μm element pitch and 4.4 MHz center frequency in air incorporating a new design approach is presented. The arrays are comprised of two wafer bonded, structured silicon-on-insulator wafers featuring an opengrid...... support structure on top of the CMUT plates, omitting the need for through wafer vias. A 5 mask process is used to produce 2-D row-column addressed CMUT arrays with 74 nm vacuum gaps, single crystalline silicon plates with optional lithographically defined mass loads, 120 V pull-in voltage, and high...
Row-Column Addressed 2-D CMUT Arrays with Integrated Apodization
DEFF Research Database (Denmark)
Christiansen, Thomas Lehrmann; Rasmussen, Morten Fischer; Jensen, Jørgen Arendt;
2014-01-01
Experimental results from row-column addressed capacitive micromachined ultrasonic transducers (CMUTs) with integrated apodization are presented. The apodization is applied by varying the density of CMUT cells in the array with the objective of damping the edge waves originating from the element...... ends. Two row-column addressed 32+32 CMUT arrays are produced using a wafer-bonding technique, one with and one without integrated apodization. Hydrophone measurements of the emitted pressure field from the array with integrated apodization show a reduction in edge wave energy of 8.4 dB (85 %) compared...
Equivalent circuit-based analysis of CMUT cell dynamics in arrays.
Oguz, H K; Atalar, Abdullah; Köymen, Hayrettin
2013-05-01
Capacitive micromachined ultrasonic transducers (CMUTs) are usually composed of large arrays of closely packed cells. In this work, we use an equivalent circuit model to analyze CMUT arrays with multiple cells. We study the effects of mutual acoustic interactions through the immersion medium caused by the pressure field generated by each cell acting upon the others. To do this, all the cells in the array are coupled through a radiation impedance matrix at their acoustic terminals. An accurate approximation for the mutual radiation impedance is defined between two circular cells, which can be used in large arrays to reduce computational complexity. Hence, a performance analysis of CMUT arrays can be accurately done with a circuit simulator. By using the proposed model, one can very rapidly obtain the linear frequency and nonlinear transient responses of arrays with an arbitrary number of CMUT cells. We performed several finite element method (FEM) simulations for arrays with small numbers of cells and showed that the results are very similar to those obtained by the equivalent circuit model. PMID:23661137
Void-Free Direct Bonding of CMUT Arrays with Single Crystalline Plates and Pull- In Insulation
DEFF Research Database (Denmark)
Christiansen, Thomas Lehrmann; Hansen, Ole; Dahl Johnsen, Mathias;
2013-01-01
alteration of the final structure and no additional fabrication steps compared to the double oxidation process. Two identical CMUT arrays with circular and square cavities having diameter/side lengths of 72 μm/65 μm and a 20 μm interdistance are fabricated with the two processes, demonstrating void-free...
A Low-noise front-end circuit for 2D cMUT arrays
Güler, Ülkühan; Guler, Ulkuhan; Bozkurt, Ayhan
2006-01-01
cMUT technology enables 2D array design with front-end electronic integration through flip-chip bonding or cMUT-on-CMOS process. The size of a 2D array element is constrained in both dimensions due to the aperture sampling criteria, and therefore should be less than or equal to the half of the wavelength in both dimensions. Considering large parasitic capacitances introduced by the interconnections, such small transducer elements necessitate integrated low noise frontends for achieving accept...
A 5 meter range non-planar CMUT array for Automotive Collision Avoidance
Hernandez Aguirre, Jonathan
A discretized hyperbolic paraboloid geometry capacitive micromachined ultrasonic transducer (CMUT) array has been designed and fabricated for automotive collision avoidance. The array is designed to operate at 40 kHz, beamwidth of 40° with a maximum sidelobe intensity of -10dB. An SOI based fabrication technology has been used for the 5x5 array with 5 sensing surfaces along each x and y axis and 7 elevation levels. An assembly and packaging technique has been developed to realize the non-planar geometry in a PGA-68 package. A highly accurate mathematical method has been presented for analytical characterization of capacitive micromachined ultrasonic transducers (CMUTs) built with square diaphragms. The method uses a new two-dimensional polynomial function to more accurately predict the deflection curve of a multilayer square diaphragm subject to both mechanical and electrostatic pressure and a new capacitance model that takes into account the contribution of the fringing field capacitances.
Underwater Imaging Using a 1 × 16 CMUT Linear Array
Rui Zhang; Wendong Zhang; Changde He; Yongmei Zhang; Jinlong Song; Chenyang Xue
2016-01-01
A 1 × 16 capacitive micro-machined ultrasonic transducer linear array was designed, fabricated, and tested for underwater imaging in the low frequency range. The linear array was fabricated using Si-SOI bonding techniques. Underwater transmission performance was tested in a water tank, and the array has a resonant frequency of 700 kHz, with pressure amplitude 182 dB ( μ Pa · m / V ) at 1 m. The −3 dB main beam width of the designed dense linear array is approximately 5 degrees. Synthetic aper...
Underwater Imaging Using a 1 × 16 CMUT Linear Array
Zhang, Rui; Zhang, Wendong; He, Changde; Zhang, Yongmei; Song, Jinlong; Xue, Chenyang
2016-01-01
A 1 × 16 capacitive micro-machined ultrasonic transducer linear array was designed, fabricated, and tested for underwater imaging in the low frequency range. The linear array was fabricated using Si-SOI bonding techniques. Underwater transmission performance was tested in a water tank, and the array has a resonant frequency of 700 kHz, with pressure amplitude 182 dB (μPa·m/V) at 1 m. The −3 dB main beam width of the designed dense linear array is approximately 5 degrees. Synthetic aperture focusing technique was applied to improve the resolution of reconstructed images, with promising results. Thus, the proposed array was shown to be suitable for underwater imaging applications. PMID:26938536
Underwater Imaging Using a 1 × 16 CMUT Linear Array.
Zhang, Rui; Zhang, Wendong; He, Changde; Zhang, Yongmei; Song, Jinlong; Xue, Chenyang
2016-01-01
A 1 × 16 capacitive micro-machined ultrasonic transducer linear array was designed, fabricated, and tested for underwater imaging in the low frequency range. The linear array was fabricated using Si-SOI bonding techniques. Underwater transmission performance was tested in a water tank, and the array has a resonant frequency of 700 kHz, with pressure amplitude 182 dB (μPa·m/V) at 1 m. The -3 dB main beam width of the designed dense linear array is approximately 5 degrees. Synthetic aperture focusing technique was applied to improve the resolution of reconstructed images, with promising results. Thus, the proposed array was shown to be suitable for underwater imaging applications. PMID:26938536
3-D Vector Flow Using a Row-Column Addressed CMUT Array
DEFF Research Database (Denmark)
Holbek, Simon; Christiansen, Thomas Lehrmann; Engholm, Mathias;
2016-01-01
cells, and second, elements areaccessed by row and/or column indices. The 62+62 2-D row-column addressed prototype CMUT probe was usedfor vector flow estimation by transmitting focused ultrasound into a flow-rig with a fully developed parabolicflow. The beam-to-flow angle was 90◦. The received data was...... characteristic parabolic velocity profile was estimated with a peak velocity of 0.48m/s ± 0.02 m/s in reference to the expected 0.54 m/s. The results presented are the first 3-D vector flow estimates obtained with a row-column CMUT probe, which demonstrates that the CMUT technology is feasiblefor 3-D flow...
Thermal-mechanical-noise-based CMUT characterization and sensing.
Gurun, Gokce; Hochman, Michael; Hasler, Paul; Degertekin, F Levent
2012-06-01
When capacitive micromachined ultrasonic transducers (CMUTs) are monolithically integrated with custom-designed low-noise electronics, the output noise of the system can be dominated by the CMUT thermal-mechanical noise both in air and in immersion even for devices with low capacitance. Because the thermal-mechanical noise can be related to the electrical admittance of the CMUTs, this provides an effective means of device characterization. This approach yields a novel method to test the functionality and uniformity of CMUT arrays and the integrated electronics when a direct connection to CMUT array element terminals is not available. Because these measurements can be performed in air at the wafer level, the approach is suitable for batch manufacturing and testing. We demonstrate this method on the elements of an 800-μm-diameter CMUT-on-CMOS array designed for intravascular imaging in the 10 to 20 MHz range. Noise measurements in air show the expected resonance behavior and spring softening effects. Noise measurements in immersion for the same array provide useful information on both the acoustic cross talk and radiation properties of the CMUT array elements. The good agreement between a CMUT model based on finite difference and boundary element methods and the noise measurements validates the model and indicates that the output noise is indeed dominated by thermal-mechanical noise. The measurement method can be exploited to implement CMUT-based passive sensors to measure immersion medium properties, or other parameters affecting the electro-mechanics of the CMUT structure. PMID:22718877
CMUT With Substrate-Embedded Springs For Non-Flexural Plate Movement.
Nikoozadeh, Amin; Khuri-Yakub, Pierre T
2010-01-01
A conventional capacitive micromachined ultrasonic transducer (CMUT) is composed of many cells connected in parallel. Since the plate in each CMUT cell is anchored at its perimeter, the average displacement is several times smaller than the displacement of an equivalent ideal piston transducer. In addition, the post areas, where the plates are anchored to, are non-active and, thus, do not contribute to the transduction. We propose a CMUT structure that resembles an ideal capacitive piston transducer, where the movable top plate only undergoes translation rather than deflection. Our proposed CMUT structure is composed of a rigid plate connected to a substrate using relatively long and narrow posts, providing the spring constant for the movement of the plate. Rather than the flexure of the plate as in a conventional CMUT, this device operates based on the compression of the compliant posts. For a capacitive transducer, a thin electrostatic gap is provided under the top plate. We used finite element analysis (FEA) to design and verify the structure's functionality. The simulation results show a fractional bandwidth of over 100% in immersion for all the designs. They also confirm that the average displacement of the top plate is above 90% of its peak displacement. We fabricated the first prototype based on this idea, which only requires a simple 3-mask fabrication process. In addition to 128-element 1-D arrays, we fabricated a variety of 240 μm × 240 μm, single-element transducers with different post configurations. We successfully measured the electrical input impedance of the fabricated devices and confirmed their resonant behavior in air. Further, we measured the acoustic pressure using a calibrated hydrophone at a known distance. Using this measurement, we calculated a peak-to-peak pressure of 1.5 MPa at the face of the transducer. Our results show that it is possible to fabricate CMUTs that exhibit ideal piston-like plate movement. Because of the substrate
Developing 1D nanostructure arrays for future nanophotonics
Directory of Open Access Journals (Sweden)
Cooke DG
2006-01-01
Full Text Available AbstractThere is intense and growing interest in one-dimensional (1-D nanostructures from the perspective of their synthesis and unique properties, especially with respect to their excellent optical response and an ability to form heterostructures. This review discusses alternative approaches to preparation and organization of such structures, and their potential properties. In particular, molecular-scale printing is highlighted as a method for creating organized pre-cursor structure for locating nanowires, as well as vapor–liquid–solid (VLS templated growth using nano-channel alumina (NCA, and deposition of 1-D structures with glancing angle deposition (GLAD. As regards novel optical properties, we discuss as an example, finite size photonic crystal cavity structures formed from such nanostructure arrays possessing highQand small mode volume, and being ideal for developing future nanolasers.
From nonfinite to finite 1D arrays of origami tiles.
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
Progress in Development of HIFU CMUTs for use under MR-guidance
International Nuclear Information System (INIS)
High intensity focused ultrasound (HIFU) guided by magnetic resonance imaging (MRI) is a noninvasive treatment that potentially reduces patient morbidity, lowers costs, and increases treatment accessibility. Traditionally, piezoelectric transducers are used for HIFU, but capacitive micromachined ultrasonic transducers (CMUTs) have many advantages, including fabrication flexibility, low loss, and efficient transmission. We designed, fabricated, and tested HIFU CMUTs for use under MRI guidance and have demonstrated continuous wave (CW) focusing. In this paper, we demonstrate that CMUTs can be designed for therapeutic ultrasound. First, we demonstrate successful unfocused heating of a HIFU phantom to 18.6 deg. C, which was successfully monitored under MR guidance. Second, we demonstrated a focused CMUT array whose beam profile matched with simulation. In the future, we will expand the array and system for upper abdominal cancer therapy.
Cooperative eigenmodes and scattering in 1D atomic arrays
Bettles, R J; Adams, C S
2016-01-01
Using a classical coupled dipole model, we numerically investigate the cooperative behavior of a one dimensional array of atomic dipoles driven by a weak laser field. Changing the polarization and direction of the driving field allows us to separately address superradiant, subradiant, red shifted, and blue shifted eigenmodes, as well as observe strong Fano-like interferences between different modes. The cooperative eigenvectors can be characterized by the phase difference between nearest neighbor dipoles, ranging from all oscillating in phase to all oscillating out of phase with their nearest neighbors. Investigating the eigenvalue behavior as a function of atom number and lattice spacing, we find that certain eigenmodes of an infinite atomic chain have the same decay rate as a single atom between two mirrors.
Simulating Capacitive Micromachined Ultrasonic Transducers (CMUTs) using Field II
DEFF Research Database (Denmark)
Bæk, David; Oralkan, Omer; Kupnik, Mario;
2010-01-01
Field II has been a recognized simulation tool for piezoceramic medical transducer arrays for more than a decade. The program has its strength in doing fast computations of the spatial impulse response (SIR) from array elements by dividing the elements into smaller mathematical elements (ME)s from...... which it calculates the SIR responses. The program features predefined models for classical transducer geometries, but currently none for the fast advancing CMUTs. This work addresses the assumptions required for modeling CMUTs with Field II. It is shown that rectangular array elements, populated with...... cells, can be well approximated by neglecting the cells. Further, it is demonstrated that scaling of the SIR translates into better computational efficiency....
Glucose sensor using periodic nanostructured hybrid 1D Au/ZnO arrays
Energy Technology Data Exchange (ETDEWEB)
Huh, Pil Ho, E-mail: pilho.huh@samsung.com [Samsung Electronics Co., Ltd. Nongseo-Dong, Giheung-Gu, Yongin-City, Gyeonggi-Do 446-711 (Korea, Republic of); Kim, Myunghwan [Samsung Electronics Co., Ltd. Nongseo-Dong, Giheung-Gu, Yongin-City, Gyeonggi-Do 446-711 (Korea, Republic of); Kim, Seong-Cheol, E-mail: sckim07@ynu.ac.kr [School of Textiles, Yeungnam University, Gyeungsan Gyeungbuk 712-749 (Korea, Republic of)
2012-07-01
Hybrid 1D nanostructured Au/ZnO arrays were created by heat treatment of a spin-coated zinc acetate-PVA-Au(III) layer on surface relief grating and functioned as an electrochemical and optical D(+)-glucose sensor due to electrochemical oxidation between hybrid nanostructures and D(+)-glucose. The morphology and chemical composition of 1D Au/ZnO hybrid arrays were characterized by means of AFM, SEM, EDAX, and XPS. Electrochemical and optical sensitivities by the addition of D(+)-glucoses on 1D Au/ZnO arrays were investigated using Cyclic voltammetry and UV-vis-NIR spectra in the medical concentration ranges of 0.5, 2.0, and 8.0 mM. - Highlights: Black-Right-Pointing-Pointer Zinc acetate-PVA-Au(III) composites were prepared by simply mixing zinc acetate-PVA and gold(III) chloride trihydrate. Black-Right-Pointing-Pointer Hybrid 1D nanostructured Au/ZnO arrays were easily fabricated using surface relief gratings without additional process steps. Black-Right-Pointing-Pointer Redox and optical sensor to detect D(+)-glucoses.
Glucose sensor using periodic nanostructured hybrid 1D Au/ZnO arrays
International Nuclear Information System (INIS)
Hybrid 1D nanostructured Au/ZnO arrays were created by heat treatment of a spin-coated zinc acetate-PVA-Au(III) layer on surface relief grating and functioned as an electrochemical and optical D(+)-glucose sensor due to electrochemical oxidation between hybrid nanostructures and D(+)-glucose. The morphology and chemical composition of 1D Au/ZnO hybrid arrays were characterized by means of AFM, SEM, EDAX, and XPS. Electrochemical and optical sensitivities by the addition of D(+)-glucoses on 1D Au/ZnO arrays were investigated using Cyclic voltammetry and UV–vis-NIR spectra in the medical concentration ranges of 0.5, 2.0, and 8.0 mM. - Highlights: ► Zinc acetate-PVA-Au(III) composites were prepared by simply mixing zinc acetate-PVA and gold(III) chloride trihydrate. ► Hybrid 1D nanostructured Au/ZnO arrays were easily fabricated using surface relief gratings without additional process steps. ► Redox and optical sensor to detect D(+)-glucoses.
A hand-held row-column addressed CMUT probe with integrated electronics for volumetric imaging
DEFF Research Database (Denmark)
Engholm, Mathias; Christiansen, Thomas Lehrmann; Beers, Christopher;
2015-01-01
A 3 MHz, λ / 2-pitch 62+62 channel row-column addressed 2-D CMUT array designed to be mounted in a probe handle and connected to a commercial BK Medical scanner for real-time volumetric imaging is presented. It is mounted and wire-bonded on a flexible PCB, which is connected to two rigid PCBs with...
Dimensional Scaling for Optimized CMUT Operations
DEFF Research Database (Denmark)
Lei, Anders; Diederichsen, Søren Elmin; la Cour, Mette Funding;
2014-01-01
This work presents a dimensional scaling study using numerical simulations, where gap height and plate thickness of a CMUT cell is varied, while the lateral plate dimension is adjusted to maintain a constant transmit immersion center frequency of 5 MHz. Two cell configurations have been simulated...
Acoustic backscatter and effective scatterer size estimates using a 2D CMUT transducer
Liu, W.; Zagzebski, J A; Hall, T.J.; Madsen, E L; Varghese, T.; Kliewer, M.A.; Panda, S.; Lowery, C; Barnes, S.
2008-01-01
Compared to conventional piezoelectric transducers, new capacitive microfabricated ultrasonic transducer (CMUT) technology is expected to offer a broader bandwidth, higher resolution and advanced 3D/4D imaging inherent in a 2D array. For ultrasound scatterer size imaging, a broader frequency range provides more information on frequency-dependent backscatter, and therefore, generally more accurate size estimates. Elevational compounding, which can significantly reduce the large statistical flu...
Mutual Radiation Impedance of Uncollapsed CMUT Cells with Different Radii
Ozgurluk, Alper; Atalar, Abdullah; Koymen, Hayrettin
2015-01-01
A polynomial approximation is proposed for the mutual acoustic impedance between uncollapsed capacitive micromachined ultrasonic transducer (CMUT) cells with different radii in an infinite rigid baffle. The resulting approximation is employed in simulating CMUTs with a circuit model. A very good agreement is obtained with the corresponding finite element simulation (FEM) result.
Integrated Reconfigurable High-Voltage Transmitting Circuit for CMUTs
DEFF Research Database (Denmark)
Llimos Muntal, Pere; Larsen, Dennis Øland; Jørgensen, Ivan Harald Holger; Bruun, Erik
2014-01-01
In this paper a full high-voltage transmitting cir- cuit aimed for capacitive micromachined ultrasonic transducers (CMUTs) used in ultrasound medical applications is designed and implemented in a 0.35 μm high-voltage CMOS process. The CMUT is single-ended driven. The design is taped-out and...
Localized self-heating in large arrays of 1D nanostructures
Monereo, O.; Illera, S.; Varea, A.; Schmidt, M.; Sauerwald, T.; Schütze, A.; Cirera, A.; Prades, J. D.
2016-02-01
One dimensional (1D) nanostructures offer a promising path towards highly efficient heating and temperature control in integrated microsystems. The so called self-heating effect can be used to modulate the response of solid state gas sensor devices. In this work, efficient self-heating was found to occur at random networks of nanostructured systems with similar power requirements to highly ordered systems (e.g. individual nanowires, where their thermal efficiency was attributed to the small dimensions of the objects). Infrared thermography and Raman spectroscopy were used to map the temperature profiles of films based on random arrangements of carbon nanofibers during self-heating. Both the techniques demonstrate consistently that heating concentrates in small regions, the here-called ``hot-spots''. On correlating dynamic temperature mapping with electrical measurements, we also observed that these minute hot-spots rule the resistance values observed macroscopically. A physical model of a random network of 1D resistors helped us to explain this observation. The model shows that, for a given random arrangement of 1D nanowires, current spreading through the network ends up defining a set of spots that dominate both the electrical resistance and power dissipation. Such highly localized heating explains the high power savings observed in larger nanostructured systems. This understanding opens a path to design highly efficient self-heating systems, based on random or pseudo-random distributions of 1D nanostructures.One dimensional (1D) nanostructures offer a promising path towards highly efficient heating and temperature control in integrated microsystems. The so called self-heating effect can be used to modulate the response of solid state gas sensor devices. In this work, efficient self-heating was found to occur at random networks of nanostructured systems with similar power requirements to highly ordered systems (e.g. individual nanowires, where their thermal
Exact electron states in 1D (quasi-) periodic arrays of delta-potentials
Kramer, Peter; Kramer, Tobias
1999-01-01
Exact one-electron eigenstates in finite parts of 1D periodic and Fibonacci chains of attractive and repulsive delta potentials are computed and analyzed. Bloch and bound state boundary conditions are related in terms of transfer matrices. Scenarios of positive and negative energy are distinguished. The dependence on the potential strength parameter is analyzed. The scattering matrix is computed. Implications for the interpretation of band germs in quasiperiodic chains are discussed.
Inclusion of Cu nano-cluster 1D arrays inside a C3-symmetric artificial oligopeptide via co-assembly
Gong, Ruiying; Li, Fei; Yang, Chunpeng; Wan, Xiaobo
2015-12-01
A peptide sequence N3-GVGV-OMe (G: glycine; V: valine) was attached to a benzene 1,3,5-tricarboxamide (BTA) derivative via ``click chemistry'' to afford a C3-symmetric artificial oligopeptide. The key feature of this oligopeptide is that the binding sites (triazole groups formed by click reaction) are located at the center, while the three oligopeptide arms with a strong tendency to assemble are located around it, which provides inner space to accommodate nanoparticles via self-assembly. The inclusion of Cu nanoclusters and the formation of one-dimensional (1D) arrays inside the nanofibers of the C3-symmetric artificial oligopeptide assembly were observed, which is quite different from the commonly observed nanoparticle growth on the surface of the pre-assembled oligopeptide nanofibers via the coordination sites located outside. Our finding provides an instructive concept for the design of other stable organic-inorganic hybrid 1D arrays with the inorganic nanoparticles inside.A peptide sequence N3-GVGV-OMe (G: glycine; V: valine) was attached to a benzene 1,3,5-tricarboxamide (BTA) derivative via ``click chemistry'' to afford a C3-symmetric artificial oligopeptide. The key feature of this oligopeptide is that the binding sites (triazole groups formed by click reaction) are located at the center, while the three oligopeptide arms with a strong tendency to assemble are located around it, which provides inner space to accommodate nanoparticles via self-assembly. The inclusion of Cu nanoclusters and the formation of one-dimensional (1D) arrays inside the nanofibers of the C3-symmetric artificial oligopeptide assembly were observed, which is quite different from the commonly observed nanoparticle growth on the surface of the pre-assembled oligopeptide nanofibers via the coordination sites located outside. Our finding provides an instructive concept for the design of other stable organic-inorganic hybrid 1D arrays with the inorganic nanoparticles inside. Electronic
Electromagnetic Wave Propagation in a Quasi-1D Rhombic Linear Optical Waveguide Array
Maimistov, Andrey I
2016-01-01
The quasi-one-dimensional rhombic array of the waveguides is considered. System of equations describing coupled waves in the waveguide in the linear limit is solved exactly. The electric field distribution was found both for the diffractionless (or dispersionless) flat band modes and for the dispersive modes.
Dimensional phase transition from an array of 1D Luttinger liquids to a 3D Bose-Einstein condensate.
Vogler, Andreas; Labouvie, Ralf; Barontini, Giovanni; Eggert, Sebastian; Guarrera, Vera; Ott, Herwig
2014-11-21
We study the thermodynamic properties of a 2D array of coupled one-dimensional Bose gases. The system is realized with ultracold bosonic atoms loaded in the potential tubes of a two-dimensional optical lattice. For negligible coupling strength, each tube is an independent weakly interacting 1D Bose gas featuring Tomonaga Luttinger liquid behavior. By decreasing the lattice depth, we increase the coupling strength between the 1D gases and allow for the phase transition into a 3D condensate. We extract the phase diagram for such a system and compare our results with theoretical predictions. Because of the high effective mass across the periodic potential and the increased 1D interaction strength, the phase transition is shifted to large positive values of the chemical potential. Our results are prototypical to a variety of low-dimensional systems, where the coupling between the subsystems is realized in a higher spatial dimension such as coupled spin chains in magnetic insulators. PMID:25479499
Ordered 1-D and 2-D InAs/InP quantum dot arrays at telecom wavelength
International Nuclear Information System (INIS)
Lateral one-dimensional (1-D) and two-dimensional (2-D) InAs/InP quantum dot (QD) arrangements are created by the concept of self-organized anisotropic strain engineering of InAs/InGaAsP superlattice (SL) templates on InP (100) and (311)B substrates by chemical-beam epitaxy (CBE). The SL templates comprise several-periods of an InAs QD layer plus a thin cap layer, post-growth annealing, and a separation layer. QDs order on top of the templates due to local strain recognition. Distinct preferential In adatom surface migration during annealing and substrate miscut lead to linear QD arrays along [001] for InP (100) substrates and a periodic square lattice aligned ±450 off [-233] for InP (311)B substrates. Optimization of the growth parameters balances In desorption and leads to well-separated and highly uniform QD arrays. Importantly, strong photoluminescence (PL) of defect-free InAs QD arrays is observed with the wavelength tuned into the 1.55-μim telecom region at room temperature through the insertion of GaAs interlayer beneath the QDs. Finally, the concept of self-organized anisotropic strain engineering for QD ordering is extended for formation of more complex architectures by combining it with step-engineering on shallow- and deep-patterned substrates. On the sidewall areas, the steps generated by the artificial patterns play the major role in determination of the In adatom surface migration during annealing, altering the QD arrays direction away from [001] on stripe-patterned InP (100) substrates. On the contrary, the sidewalls on patterned InP (311)B are faceted, not affecting the orientation of the 2-D InAs QD arrays.
Capacitive micromachined ultrasonic transducer arrays as tunable acoustic metamaterials.
Lani, Shane W; Wasequr Rashid, M; Hasler, Jennifer; Sabra, Karim G; Levent Degertekin, F
2014-02-01
Capacitive Micromachined Ultrasonic Transducers (CMUTs) operating in immersion support dispersive evanescent waves due to the subwavelength periodic structure of electrostatically actuated membranes in the array. Evanescent wave characteristics also depend on the membrane resonance which is modified by the externally applied bias voltage, offering a mechanism to tune the CMUT array as an acoustic metamaterial. The dispersion and tunability characteristics are examined using a computationally efficient, mutual radiation impedance based approach to model a finite-size array and realistic parameters of variation. The simulations are verified, and tunability is demonstrated by experiments on a linear CMUT array operating in 2-12 MHz range. PMID:24753623
Capacitive micromachined ultrasonic transducer arrays as tunable acoustic metamaterials
International Nuclear Information System (INIS)
Capacitive Micromachined Ultrasonic Transducers (CMUTs) operating in immersion support dispersive evanescent waves due to the subwavelength periodic structure of electrostatically actuated membranes in the array. Evanescent wave characteristics also depend on the membrane resonance which is modified by the externally applied bias voltage, offering a mechanism to tune the CMUT array as an acoustic metamaterial. The dispersion and tunability characteristics are examined using a computationally efficient, mutual radiation impedance based approach to model a finite-size array and realistic parameters of variation. The simulations are verified, and tunability is demonstrated by experiments on a linear CMUT array operating in 2-12 MHz range
Capacitive micromachined ultrasonic transducer arrays as tunable acoustic metamaterials
Energy Technology Data Exchange (ETDEWEB)
Lani, Shane W., E-mail: shane.w.lani@gmail.com, E-mail: karim.sabra@me.gatech.edu, E-mail: levent.degertekin@me.gatech.edu; Sabra, Karim G. [George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, 801Ferst Drive, Georgia 30332-0405 (United States); Wasequr Rashid, M.; Hasler, Jennifer [School of Electrical and Computer Engineering, Georgia Institute of Technology, Van Leer Electrical Engineering Building, 777 Atlantic Drive NW, Atlanta, Georgia 30332-0250 (United States); Levent Degertekin, F. [George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, 801Ferst Drive, Georgia 30332-0405 (United States); School of Electrical and Computer Engineering, Georgia Institute of Technology, Van Leer Electrical Engineering Building, 777 Atlantic Drive NW, Atlanta, Georgia 30332-0250 (United States)
2014-02-03
Capacitive Micromachined Ultrasonic Transducers (CMUTs) operating in immersion support dispersive evanescent waves due to the subwavelength periodic structure of electrostatically actuated membranes in the array. Evanescent wave characteristics also depend on the membrane resonance which is modified by the externally applied bias voltage, offering a mechanism to tune the CMUT array as an acoustic metamaterial. The dispersion and tunability characteristics are examined using a computationally efficient, mutual radiation impedance based approach to model a finite-size array and realistic parameters of variation. The simulations are verified, and tunability is demonstrated by experiments on a linear CMUT array operating in 2-12 MHz range.
Singulation for imaging ring arrays of capacitive micromachined ultrasonic transducers
International Nuclear Information System (INIS)
Singulation of MEMS is a critical step in the transition from wafer-level to die-level devices. As is the case for capacitive micromachined ultrasound transducer (CMUT) ring arrays, an ideal singulation must protect the fragile membranes from the processing environment while maintaining a ring array geometry. The singulation process presented in this paper involves bonding a trench-patterned CMUT wafer onto a support wafer, deep reactive ion etching (DRIE) of the trenches, separating the CMUT wafer from the support wafer and de-tethering the CMUT device from the CMUT wafer. The CMUT arrays fabricated and singulated in this process were ring-shaped arrays, with inner and outer diameters of 5 mm and 10 mm, respectively. The fabricated CMUT ring arrays demonstrate the ability of this method to successfully and safely singulate the ring arrays and is applicable to any arbitrary 2D shaped MEMS device with uspended microstructures, taking advantage of the inherent planar attributes of DRIE. (technical note)
Energy Technology Data Exchange (ETDEWEB)
Doh, Il; Kim, Yong Tae; Ahn, Bong Young [Center for Medical Metrology, Korea Research Institute of Standards and Science, Daejeon (Korea, Republic of); Kim, Kwang Youn [Meta biomed Co.,Ltd, Cheongju (Korea, Republic of)
2015-04-15
This paper describes the construction of a static 3D ultrasonography image by tracking the radiation beam position during the handy operation of a 1D array probe to enable point-of-care use. The theoretical model of the transformation from the translational and rotational information of the sensor mounted on the probe to the reference Cartesian coordinate system was given. The signal amplification and serial communication interface module was made using a commercially available sensor. A test phantom was also made using silicone putty in a donut shape. During the movement of the hand-held probe, B-mode movie and sensor signals were recorded. B-mode images were periodically selected from the movie, and the gray levels of the pixels for each image were converted to the gray levels of 3D voxels. 3D and 2D images of arbitrary cross-section of the B-mode type were also constructed from the voxel data, and agreed well with the shape of the test phantom.
Integrated differential high-voltage transmitting circuit for CMUTs
DEFF Research Database (Denmark)
Llimos Muntal, Pere; Larsen, Dennis Øland; Farch, Kjartan;
2015-01-01
In this paper an integrated differential high-voltage transmitting circuit for capacitive micromachined ultrasonic transducers (CMUTs) used in portable ultrasound scanners is designed and implemented in a 0.35 μm high-voltage process. Measurements are performed on the integrated circuit in order...... to assess its performance. The circuit generates pulses at differential voltage levels of 60V, 80V and 100 V, a frequency up to 5MHz and a measured driving strength of 1.75 V/ns with the CMUT connected. The total on-chip area occupied by the transmitting circuit is 0.18 mm2 and the power consumption...
Integrated reconfigurable high-voltage transmitting circuit for CMUTs
DEFF Research Database (Denmark)
Llimos Muntal, Pere; Larsen, Dennis Øland; Jørgensen, Ivan Harald Holger;
2015-01-01
In this paper a high-voltage transmitting circuit aimed for capacitive micromachined ultrasonic transducers (CMUTs) used in scanners for medical applications is designed and implemented in a 0.35 μm high-voltage CMOS process. The transmitting circuit is reconfigurable externally making it able...... to drive a wide variety of CMUTs. The transmitting circuit can generate several pulse shapes with voltages up to 100 V, maximum pulse range of 50 V, frequencies up to 5 MHz and different driving slew rates. Measurements are performed on the circuit in order to assess its functionality and power consumption...
Capacitive micromachined ultrasonic transducer arrays as tunable acoustic metamaterials
Lani, Shane W.; Wasequr Rashid, M.; Hasler, Jennifer; Sabra, Karim G.; Levent Degertekin, F.
2014-01-01
Capacitive Micromachined Ultrasonic Transducers (CMUTs) operating in immersion support dispersive evanescent waves due to the subwavelength periodic structure of electrostatically actuated membranes in the array. Evanescent wave characteristics also depend on the membrane resonance which is modified by the externally applied bias voltage, offering a mechanism to tune the CMUT array as an acoustic metamaterial. The dispersion and tunability characteristics are examined using a computationally ...
Modeling and Measurements of CMUTs with Square Anisotropic Plates
DEFF Research Database (Denmark)
la Cour, Mette Funding; Christiansen, Thomas Lehrmann; Dahl-Petersen, Christian;
2013-01-01
The conventional method of modeling CMUTs use the isotropic plate equation to calculate the deflection, leading to deviations from FEM simulations including anisotropic effects of around 10% in center deflection. In this paper, the deflection is found for square plates using the full anisotropic ...
Investigation of PDMS as coating on CMUTs for Imaging
DEFF Research Database (Denmark)
la Cour, Mette Funding; Stuart, Matthias Bo; Laursen, Mads Bjerregaard;
2014-01-01
A protective layer is necessary for Capacitive Mi- cromachined Ultrasonic Transducers (CMUTs) to be used for imaging purpose. The layer should both protect the device itself and the patient while maintaining the performance of the device. In this work Sylgard 170 PDMS is tested as coating material...
Directory of Open Access Journals (Sweden)
Abd Rahman Mohd Yusri
2011-01-01
Full Text Available Abstract A simple method for the synthesis of ZnO nanofilms composed of vertical array of quasi-1D ZnO nanostructures (quasi-NRs on the surface was demonstrated via a 1D crystal growth of the attached nanoseeds under a rapid hydrolysis process of zinc salts in the presence of ammonia at room temperature. In a typical procedure, by simply controlling the concentration of zinc acetate and ammonia in the reaction, a high density of vertically oriented nanorod-like morphology could be successfully obtained in a relatively short growth period (approximately 4 to 5 min and at a room-temperature process. The average diameter and the length of the nanostructures are approximately 30 and 110 nm, respectively. The as-prepared quasi-NRs products were pure ZnO phase in nature without the presence of any zinc complexes as confirmed by the XRD characterisation. Room-temperature optical absorption spectroscopy exhibits the presence of two separate excitonic characters inferring that the as-prepared ZnO quasi-NRs are high-crystallinity properties in nature. The mechanism of growth for the ZnO quasi-NRs will be proposed. Due to their simplicity, the method should become a potential alternative for a rapid and cost-effective preparation of high-quality ZnO quasi-NRs nanofilms for use in photovoltaic or photocatalytics applications. PACS: 81.07.Bc; 81.16.-c; 81.07.Gf.
Output pressure and harmonic characteristics of a CMUT as function of bias and excitation voltage
DEFF Research Database (Denmark)
Lei, Anders; Diederichsen, Søren Elmin; Hansen, Sebastian Molbech; Stuart, Matthias Bo; Bouzari, Hamed; Jensen, Jørgen Arendt; Thomsen, Erik Vilain
The large bandwidth makes CMUT based transducers interesting for both conventional and harmonic imaging. The inherent nonlinear behavior of the CMUT, however, poses an issue for harmonic imaging as it is difficult to dissociate the harmonics generated in the tissue from the harmonic content of the...
Yang, Daquan; Wang, Chuan; Ji, Yuefeng
2016-07-25
We propose a novel multiplexed ultra-compact high-sensitivity one-dimensional (1D) photonic crystal (PC) nanobeam cavity sensor array on a monolithic silicon chip, referred to as Parallel Integrated 1D PC Nanobeam Cavity Sensor Array (PI-1DPC-NCSA). The performance of the device is investigated numerically with three-dimensional finite-difference time-domain (3D-FDTD) technique. The PI-1DPC-NCSA consists of multiple parallel-connected channels of integrated 1D PC nanobeam cavities/waveguides with gap separations. On each channel, by connecting two additional 1D PC nanobeam bandstop filters (1DPC-NBFs) to a 1D PC nanobeam cavity sensor (1DPC-NCS) in series, a transmission spectrum with a single targeted resonance is achieved for the purpose of multiplexed sensing applications. While the other spurious resonances are filtered out by the stop-band of 1DPC-NBF, multiple 1DPC-NCSs at different resonances can be connected in parallel without spectrum overlap. Furthermore, in order for all 1DPC-NCSs to be integrated into microarrays and to be interrogated simultaneously with a single input/output port, all channels are then connected in parallel by using a 1 × n taper-type equal power splitter and a n × 1 S-type power combiner in the input port and output port, respectively (n is the channel number). The concept model of PI-1DPC-NCSA is displayed with a 3-parallel-channel 1DPC-NCSs array containing series-connected 1DPC-NBFs. The bulk refractive index sensitivities as high as 112.6nm/RIU, 121.7nm/RIU, and 148.5nm/RIU are obtained (RIU = Refractive Index Unit). In particular, the footprint of the 3-parallel-channel PI-1DPC-NCSA is 4.5μm × 50μm (width × length), decreased by more than three orders of magnitude compared to 2D PC integrated sensor arrays. Thus, this is a promising platform for realizing ultra-compact lab-on-a-chip applications with high integration density and high parallel-multiplexing capabilities. PMID:27464080
Wang, Zhe
2010-10-01
We report superconducting resistive transition characteristics for array(s) of coupled 4-Angstrom single wall carbon nanotubes embedded in aluminophosphate-five zeolite. The transition was observed to initiate at 15 K with a slow resistance decrease switching to a sharp, order of magnitude drop between 7.5 and 6.0 K with strong (anisotropic) magnetic field dependence. Both the sharp resistance drop and its attendant nonlinear IV characteristics are consistent with the manifestations of a Berezinskii-Kosterlitz-Thouless transition that establishes quasi long range order in the plane transverse to the c-axis of the nanotubes, leading to an inhomogeneous system comprising 3D superconducting regions connected by weak links. Global coherence is established at below 5 K with the appearance of a well-defined supercurrent gap/low resistance region at 2 K. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Directory of Open Access Journals (Sweden)
Nguyen Van Toan
2016-04-01
Full Text Available This paper presents a process for the fabrication of vacuum-sealed capacitive micromachined ultrasonic transducer (CMUT arrays using glass reflow and anodic bonding techniques. Silicon through-wafer interconnects have been investigated by the glass reflow process. Then, the patterned silicon-glass reflow wafer is anodically bonded to an SOI (silicon-on-insulator wafer for the fabrication of CMUT devices. The CMUT 5 × 5 array has been successfully fabricated. The resonant frequency of the CMUT array with a one-cell radius of 100 µm and sensing gap of 3.2 µm (distance between top and bottom electrodes is observed at 2.84 MHz. The Q factor is approximately 1300 at pressure of 0.01 Pa.
Sato, M; Shi, W; Shige, S; Ishikawa, T; Soga, Y; Hubbard, B E; Ilic, B; Sievers, A J
2014-01-01
Both low frequency and high frequency impurity modes have been produced in a SiN micromechanical cantilever array by illumination with either an infrared or visible laser. When such laser-induced impurities are placed near a driven intrinsic localized mode (ILM) it is either repelled or attracted. By measuring the linear response spectrum for these two cases it was found that vibrational hopping of the ILM takes place when the natural frequency of the ILM and an even symmetry linear local mode are symmetrically located about the driven ILM frequency so that parametric excitation of these two linear modes is enhanced, amplifying the lateral motion of the ILM. Numerical simulations are consistent with these signature findings. It is also demonstrated that the correct sign of the observed interaction can be found with a harmonic lattice-impurity model but the magnitude of the effect is enhanced in a nonlinear lattice.
Modeling and Measuring the Effects of Mutual Impedance on Multi-Cell CMUT Configurations
Park, K. K.; Kupnik, M.; Lee, H. J.; Khuri-Yakub, B. T.; Wygant, I. O.
2010-01-01
This paper presents a numerical method for calculating the frequency response of a CMUT with a large number of cells. In a multi-cell configuration, commonly found in CMUTs, each cell is affected by the acoustic loading from neighboring cells. Thus, for an accurate model of a multi-cell CMUT element it is better to consider the mutual acoustic impedance instead of the acoustic impedance of a single cell only. We calculate the velocity of every cell (plate movement) simultaneously, with the mu...
Parametric nonlinear lumped element model for circular CMUTs in collapsed mode.
Aydoğdu, Elif; Ozgurluk, Alper; Atalar, Abdullah; Köymen, Hayrettin
2014-01-01
We present a parametric equivalent circuit model for a circular CMUT in collapsed mode. First, we calculate the collapsed membrane deflection, utilizing the exact electrical force distribution in the analytical formulation of membrane deflection. Then we develop a lumped element model of collapsed membrane operation. The radiation impedance for collapsed mode is also included in the model. The model is merged with the uncollapsed mode model to obtain a simulation tool that handles all CMUT behavior, in transmit or receive. Large- and small-signal operation of a single CMUT can be fully simulated for any excitation regime. The results are in good agreement with FEM simulations. PMID:24402904
Luo, Xi-Wang; Li, Chuan-Feng; Xu, Jin-Shi; Guo, Guang-Can; Zhou, Zheng-Wei
2015-01-01
Orbital angular momentum (OAM) of light is a fundamental optical degree of freedom that has recently motivated much exciting research in diverse fields ranging from optical communication to quantum information. We show for the first time that it is also a unique and valuable resource for quantum simulation, by demonstrating theoretically how \\emph{2d} topological physics can be simulated in a \\emph{1d} array of optical cavities using OAM-carrying photons. Remarkably, this newly discovered application of OAM states not only reduces required physical resources but also increases feasible scale of simulation. By showing how important topics such as edge-state transport and topological phase transition can be studied in a small simulator with just a few cavities ready for immediate experimental exploration, we demonstrate the prospect of photonic OAM for quantum simulation which can have a significant impact on the research of topological physics.
Electrostatic and Small-Signal Analysis of CMUTs With Circular and Square Anisotropic Plates
DEFF Research Database (Denmark)
la Cour, Mette Funding; Christiansen, Thomas Lehrmann; Jensen, Jørgen Arendt;
2015-01-01
Traditionally, Capacitive Micromachined Ultrasonic Transducers (CMUTs) are modeled using the isotropic plate equation and this leads to deviations between analytical calcu- lations and Finite Element Modeling (FEM). In this paper, the deflection is calculated for both circular and square plates...
CMUTs with High-K Atomic Layer Deposition Dielectric Material Insulation Layer
Xu, Toby; Tekes, Coskun; Degertekin, F. Levent
2014-01-01
Use of high-κ dielectric, atomic layer deposition (ALD) materials as an insulation layer material for capacitive micromachined ultrasonic transducers (CMUTs) is investigated. The effect of insulation layer material and thickness on CMUT performance is evaluated using a simple parallel plate model. The model shows that both high dielectric constant and the electrical breakdown strength are important for the dielectric material, and significant performance improvement can be achieved, especiall...
Air damping effect on the air-based CMUT operation
Cha, Bu-Sang; Kanashima, Takeshi; Lee, Seung-Mok; Okuyama, Masanori
2015-08-01
The vibration amplitude, damping ratio and viscous damping force in capacitive micromachinedultrasonic transducers (CMUTs) with a perforated membrane have been calculated theoretically and compared with the experimental data on its vibration behavior. The electrical bias of the DC and the AC voltages and the operation frequency conditions influence the damping effect because leads to variations in the gap height and the vibration velocity of the membrane. We propose a new estimation method to determine the damping ratio by the decay rate of the vibration amplitudes of the perforated membrane plate are measured using a laser vibrometer at each frequency, and the damping ratios were calculated from those results. The influences of the vibration frequency and the electrostatic force on the damping effect under the various operation conditions have been studied.
CMUTs with high-K atomic layer deposition dielectric material insulation layer.
Xu, Toby; Tekes, Coskun; Degertekin, F
2014-12-01
Use of high-κ dielectric, atomic layer deposition (ALD) materials as an insulation layer material for capacitive micromachined ultrasonic transducers (CMUTs) is investigated. The effect of insulation layer material and thickness on CMUT performance is evaluated using a simple parallel plate model. The model shows that both high dielectric constant and the electrical breakdown strength are important for the dielectric material, and significant performance improvement can be achieved, especially as the vacuum gap thickness is reduced. In particular, ALD hafnium oxide (HfO2) is evaluated and used as an improvement over plasma-enhanced chemical vapor deposition (PECVD) silicon nitride (Six)Ny)) for CMUTs fabricated by a low-temperature, complementary metal oxide semiconductor transistor-compatible, sacrificial release method. Relevant properties of ALD HfO2) such as dielectric constant and breakdown strength are characterized to further guide CMUT design. Experiments are performed on parallel fabricated test CMUTs with 50-nm gap and 16.5-MHz center frequency to measure and compare pressure output and receive sensitivity for 200-nm PECVD Six)Ny) and 100-nm HfO2) insulation layers. Results for this particular design show a 6-dB improvement in receiver output with the collapse voltage reduced by one-half; while in transmit mode, half the input voltage is needed to achieve the same maximum output pressure. PMID:25474786
Feasibility of MR-temperature mapping of ultrasonic heating from a CMUT.
Wong, Serena H; Watkins, Ronald D; Kupnik, Mario; Pauly, Kim Butts; Khuri-Yakub, Butrus T
2008-04-01
In the last decade, high intensity focused ultrasound (HIFU) has gained popularity as a minimally invasive and noninvasive therapeutic tool for treatment of cancers, arrhythmias, and other medical conditions. HIFU therapy is often guided by magnetic resonance imaging (MRI), which provides anatomical images for therapeutic device placement, temperature maps for treatment guidance, and postoperative evaluation of the region of interest. While piezoelectric transducers are dominantly used for MR-guided HIFU, capacitive micromachined ultrasonic transducers (CMUTs) show competitive advantages, such as ease of fabrication, integration with electronics, improved efficiency, and reduction of self-heating. In this paper, we will show our first results of an unfocused CMUT transducer monitored by MR-temperature maps. This 2.51 mm by 2.32 mm, unfocused CMUT heated a HIFU phantom by 14 degrees C in 2.5 min. This temperature rise was successfully monitored by MR thermometry in a 3.0 T General Electric scanner. PMID:18467225
PECVD low stress silicon nitride analysis and optimization for the fabrication of CMUT devices
International Nuclear Information System (INIS)
Two technological options to achieve a high deposition rate, low stress plasma-enhanced chemical vapor deposition (PECVD) silicon nitride to be used in capacitive micromachined ultrasonic transducers (CMUT) fabrication are investigated and presented. Both options are developed and implemented on standard production line PECVD equipment in the framework of a CMUT technology transfer from R and D to production. A tradeoff between deposition rate, residual stress and electrical properties is showed. The first option consists in a double layer of silicon nitride with a relatively high deposition rate of ∼100 nm min−1 and low compressive residual stress, which is suitable for the fabrication of the thick nitride layer used as a mechanical support of the CMUTs. The second option involves the use of a mixed frequency low-stress silicon nitride with outstanding electrical insulation capability, providing improved mechanical and electrical integrity of the CMUT active layers. The behavior of the nitride is analyzed as a function of deposition parameters and subsequent annealing. The nitride layer characterization is reported in terms of interfaces density influence on residual stress, refractive index, deposition rate, and thickness variation both as deposited and after thermal treatment. A sweet spot for stress stability is identified at an interfaces density of 0.1 nm−1, yielding 87 MPa residual stress after annealing. A complete CMUT device fabrication is reported using the optimized nitrides. The CMUT performance is tested, demonstrating full functionality in ultrasound imaging applications and an overall performance improvement with respect to previous devices fabricated with non-optimized silicon nitride. (paper)
Integrated Differential Three-Level High-Voltage Pulser Output Stage for CMUTs
DEFF Research Database (Denmark)
Llimos Muntal, Pere; Larsen, Dennis Øland; Jørgensen, Ivan Harald Holger;
2015-01-01
A new integrated differential three-level highvoltage pulser output stage to drive capacitive micromachined ultrasonic transducers (CMUTs) is proposed in this paper. A topology comparison between the new differential output stage and the most commonly used single-ended topology is performed...... levels of 60, 80, 100V using 0.039mm2 of chip area. The power consumption is 0.951mW for a 30 pF CMUT load. The design presented is implemented in a 0.35 μm high-voltage process....
Pull-In Analysis of the Flat Circular CMUT Cell Featuring Sealed Cavity
Directory of Open Access Journals (Sweden)
Wen Zhang
2015-01-01
Full Text Available Capacitive micromachined ultrasonic transducers (CMUTs are one of the appealing MEMS devices. Most studies treat CMUTs as rigid plates vibrating in open air, ignoring the mechanical boundary conditions for simplification and resulting in cumulative errors in coupled fields. This paper presents a new analytical model for the pull-in characteristics of the flat circular CMUT cell featuring sealed cavity. Utilizing the plate theory coupled with Boyle’s law, the paper establishes a strong relation between the pressures inside the sealed cavity and the pull-in characteristics for the first time. Not only did we point out that the existence of the pressure inside the sealed cavity cannot be omitted, but we also quantified the direct effect of the pressure ratios on the pull-in phenomenon. The pull-in voltages increase while the pull-in ratios decrease with the pressure ratios of the pressure inside the sealed cavity to the ambient pressure. The proposed calculation process delivers a good approximation of the pull-in voltages and displacements, which are consistent with COMSOL simulation results. Particularly, the percentage error of our calculation process is 6.986% for the worst case. Therefore, our proposed analytical model accurately and efficiently predicts the pull-in characteristics and this paper offers new perspectives and reference value in designing and modeling the CMUTs.
Acoustical cross-talk in row–column addressed 2-D transducer arrays for ultrasound imaging
DEFF Research Database (Denmark)
Christiansen, Thomas Lehrmann; Jensen, Jørgen Arendt; Thomsen, Erik Vilain
2015-01-01
The acoustical cross-talk in row–column addressed 2-D transducer arrays for volumetric ultrasound imaging is investigated. Experimental results from a 2.7 MHz, λ/2-pitch capacitive micromachined ultrasonic transducer (CMUT) array with 62 rows and 62 columns are presented and analyzed in the...
Wong, Serena H.; Wygant, Ira O.; Yeh, David T.; Zhuang, Xuefeng; Bayram, Baris; Kupnik, Mario; Oralkan, Omer; Ergun, A. Sanli; Yaralioglu, Goksen G.; Khuri-Yakub, Butrus T.
2006-05-01
In recent years, medical procedures have become increasingly non-invasive. These include endoscopic procedures and intracardiac interventions (e.g., pulmonary vein isolation for treatment of atrial fibrillation and plaque ablation for treatment of arteriosclerosis). However, current tools suffer from poor visualization and difficult coordination of multiple therapeutic and imaging devices. Dual-mode (imaging and therapeutic) ultrasound arrays provide a solution to these challenges. A dual-mode transducer can provide focused, noncontact ultrasound suitable for therapy and can be used to provide high quality real-time images for navigation and monitoring of the procedure. In the last decade, capacitive micromachined ultrasonic transducers (CMUTs), have become an attractive option for ultrasonic imaging systems due to their fabrication flexibility, improved bandwidth, and integration with electronics. The CMUT's potential in therapeutic applications has also been demonstrated by surface output pressures as high as 1MPa peak to peak and continuous wave (CW) operation. This paper reviews existing interventional CMUT arrays, demonstrates the feasibility of CMUTs for high intensity focused ultrasound (HIFU), and presents a design for the next-generation CMUTs for integrated imaging and HIFU endoscopic catheters.
Electrostatic and Small-Signal Analysis of CMUTs With Circular and Square Anisotropic Plates.
Funding la Cour, Mette; Christiansen, Thomas Lehrmann; Jensen, Jørgen Arendt; Thomsen, Erik Vilain
2015-08-01
Traditionally, capacitive micromachined ultrasonic transducers (CMUTs) are modeled using the isotropic plate equation, and this leads to deviations between analytical calculations and finite element modeling (FEM). In this paper, the deflection is calculated for both circular and square plates using the full anisotropic plate equation. It is shown that the anisotropic calculations match excellently with FEM, whereas an isotropic approach causes up to 10% deviations in deflection. For circular plates, an exact solution can be found. For square plates using the Galerkin method, and utilizing the symmetry of the silicon crystal, a compact and accurate expression for the deflection can be obtained. The deviation from FEM in center deflection is multilayer plates is also applied to the CMUT. The deflection of a square plate was measured on fabricated CMUTs using a white light interferometer. Fitting the plate parameter for the anisotropic calculated deflection to the measurement, a deviation of 0.07% is seen. Electrostatic and small-signal dynamic analysis are performed using energy considerations including anisotropy. The stable position, effective spring constant, pullin distance, and pull-in voltage are found for both circular and square anisotropic plates, and the pressure dependence is included by comparison with the corresponding analysis for a parallel plate. Measurements on fabricated devices with both circular and square plates subjected to increasing bias voltage are performed, and it is observed that the models including anisotropic effects are within the uncertainty interval of the measurements. Finally, a lumped element small-signal model for both circular and square anisotropic plates is derived to describe the dynamics of the CMUT. PMID:26492637
Progresses in cMUT device fabrication using low temperature processes
Bahette, E.; Michaud, J. F.; Certon, D.; Gross, D.; Alquier, D.
2014-04-01
In this paper, we present an original fabrication process of capacitive micromachined ultrasonic transducers (cMUTs) using a low temperature method for high frequency medical imaging applications. The process, which is limited to 400 °C, is based on surface micromachining. The material choices are adapted in order to respect the thermal specifications allowing monolithic integration. Thus, we have found alternative methods to replace the usual high temperature steps in cMUT elaboration. In this way, a nickel silicide layer, presenting good physical and electrical characteristics, is used as a bottom electrode. The membrane, silicon nitride, is deposited using a 200 °C PECVD process. Then, a metallic layer is chosen as a sacrificial layer, in order to achieve the cavity. For that, nickel has been chosen due to its low roughness and its high etching selectivity during the excavation. After their fabrication, the transducers have been tested to verify their functionality and, thus, to validate this low temperature process. Device physical properties have been determined by electrical and optical measurement in air. We evaluated resonance frequency, collapse voltage and electromechanical coupling coefficient in accordance with the simulation. Eventually, low charging effects and low initial deflections can predict good long-term use and ageing of the cMUTs.
International Nuclear Information System (INIS)
We witnessed an initial hyped period and enthusiasm on carbon nano tubes in the 1990s later went through a significant expansion into nano tubes of other materials (metal di chalcogenides, boron nitride, etc.) as well as various nano wires and nano rods. While much of the hype might have gone, the research on one-dimensional (1D) nano materials has matured as one of the most active research areas within the nano science and nano technology community, flourishing with ample, exciting, and new research opportunities. Just like any other research frontier, researchers working in the 1D nano materials field are constantly striving to develop new fundamental science as well as potential applications. It remains a common belief that versatility and tunability of 1D nano materials would challenge many new rising tasks coming from our resource and energy demanding modern society. The traditional semiconductor industry has produced so many devices and systems from transistors, sensors, lasers, and LEDs to more sophisticated solar panels, which are now part of our daily lives. By down sizing the core components or parts to 1D form, one might wonder how fundamentally the dimensionality and morphology would impact the device performance, this is, as always, requiring us to fully understand the structure-property relationship in 1D nano materials. It may be equally crucial in connecting discovery-driven fundamental science to market-driven technology industry concerning potentially relevant findings derived from these novel materials. The importance of a platform that allows active researchers in this field to present their new development in a timely and efficient manner is therefore self-evident. Following the success of two early special issues devoted to 1D nano materials, this is the third one in a row organized by the same group of guest editors, attesting that such a platform has been well received by the readers
One-Dimensional (1-D) Nanoscale Heterostructures
Institute of Scientific and Technical Information of China (English)
Guozhen SHEN; Di CHEN; Yoshio BANDO; Dmitri GOLBERG
2008-01-01
One-dimensional (1-D) nanostructures have been attracted much attention as a result of their exceptional properties, which are different from bulk materials. Among 1-D nanostructures, 1-D heterostructures with modulated compositions and interfaces have recently become of particular interest with respect to potential applications in nanoscale building blocks of future optoelectronic devices and systems. Many kinds of methods have been developed for the synthesis of 1-D nanoscale heterostructures. This article reviews the most recent development, with an emphasize on our own recent efforts, on 1-D nanoscale heterostructures, especially those synthesized from the vapor deposition methods, in which all the reactive precursors are mixed together in the reaction chamber. Three types of 1-D nanoscale heterostructures, defined from their morphologies characteristics, are discussed in detail, which include 1-D co-axial core-shell heterostructures, 1-D segmented heterostructures and hierarchical heterostructures. This article begins with a brief survey of various methods that have been developed for synthesizing 1-D nanoscale heterostructures and then mainly focuses on the synthesis, structures and properties of the above three types of nanoscale heterostructures. Finally, this review concludes with personal views towards the topic of 1-D nanoscale heterostructures.
1-D ELECTRO-OPTIC BEAM STEERING DEVICE
Wang, Wei-Chih; Tsui, Chi Leung
2011-01-01
In this paper, we present the design and fabrication of a 1D beam steering device based on planar electro-optic thermal-plastic prisms and a collimator lens array. With the elimination of moving parts, the proposed device is able to overcome the mechanical limitations of present scanning devices, such as fatigue and low operating frequency, while maintaining a small system footprint (~0.5mm×0.5mm). From experimental data, our prototype device is able to achieve a maximum deflection angle of 5...
Akhbari, Sina; Sammoura, Firas; Lin, Liwei
2016-03-01
Equivalent circuit models of large arrays of curved (spherical shape) and flat piezoelectric micromachined ultrasonic transducers (pMUTs) have been developed for complex pMUT arrays design and analysis. The exact solutions for circuit parameters in the electromechanical domain, such as mechanical admittance, input electrical impedance, and electromechanical transformer ratio, were analytically derived. By utilizing the array solution methods previously established for the thickness-mode piezoelectric devices and capacitive micromachined ultrasonic transducers (cMUTs), the single pMUT circuit model can be extended to models for array structures. The array model includes both the self- and mutual-acoustic radiation impedances of individual transducers in the acoustic medium. Volumetric displacement, induced piezoelectric current, and pressure field can be derived with respect to the input voltage matrix, material, and geometrical properties of each individual transducer and the array structure. As such, the analytical models presented here can be used as a guideline for analyses and design evaluations of large arrays of curved and flat pMUTs efficiently and can be further generalized to evaluate other pMUT architectures in the form of single devices or arrays. PMID:26863658
Social exploration of 1D games
DEFF Research Database (Denmark)
Valente, Andrea; Marchetti, Emanuela
2013-01-01
In this paper the apparently meaningless concept of a 1 dimensional computer game is explored, via netnography. A small number of games was designed and implemented, in close contact with online communities of players and developers, providing evidence that 1 dimension is enough to produce intere...... interesting gameplay, to allow for level design and even to leave room for artistic considerations on 1D rendering. General techniques to re-design classic 2D games into 1D are also emerging from this exploration....
Epitaxial 1D electron transport layers for high-performance perovskite solar cells.
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
YORP torques with 1D thermal model
Breiter, Slawomir; Czekaj, Maria
2010-01-01
A numerical model of the Yarkovsky-O'Keefe-Radzievskii-Paddack (YORP) effect for objects defined in terms of a triangular mesh is described. The algorithm requires that each surface triangle can be handled independently, which implies the use of a 1D thermal model. Insolation of each triangle is determined by an optimized ray-triangle intersection search. Surface temperature is modeled with a spectral approach; imposing a quasi-periodic solution we replace heat conduction equation by the Helmholtz equation. Nonlinear boundary conditions are handled by an iterative, FFT based solver. The results resolve the question of the YORP effect in rotation rate independence on conductivity within the nonlinear 1D thermal model regardless of the accuracy issues and homogeneity assumptions. A seasonal YORP effect in attitude is revealed for objects moving on elliptic orbits when a nonlinear thermal model is used.
1D ferrimagnetism in homometallic chains
Coronado Miralles, Eugenio; Gómez García, Carlos José; Borrás Almenar, Juan José
1990-01-01
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. ,
ZnO 1-D nanostructures: Low temperature synthesis and characterizations
Indian Academy of Sciences (India)
Apurba Dev; S Chaudhuri; B N Dev
2008-06-01
ZnO is one of the most important semiconductors having a wide variety of applications in photonic, field emission and sensing devices. In addition, it exhibits a wide variety of morphologies in the nano regime that can be grown by tuning the growth habit of the ZnO crystal. Among various nanostructures, oriented 1-D nanoforms are particularly important for applications such as UV laser, sensors, UV LED, field emission displays, piezoelectric nanogenerator etc. We have developed a soft chemical approach to fabricate well-aligned arrays of various 1-D nanoforms like nanonails, nanowires and nanorods. The microstructural and photoluminescence properties of all the structures were investigated and tuned by varying the synthesis parameters. Field emission study from the aligned nanorod arrays exhibited high current density and a low turn-on field. These arrays also exhibited very strong UV emission and week defect emission. These structures can be utilized to fabricate efficient UV LEDs.
1-D EQUILIBRIUM DISCRETE DIFFUSION MONTE CARLO
Energy Technology Data Exchange (ETDEWEB)
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.
Diagnostics from a 1-D atmospheric column
Energy Technology Data Exchange (ETDEWEB)
Flatley, J.M.; Mace, G. [Pennsylvania State Univ., University Park, PA (United States)
1996-04-01
Various diagnostics were computed from an array of radiosondes during an intensive field operation arranged by the Atmospheric Radiation Measurement Program. The network data was centered around the site at Lamont, Oklahoma. The apparent heat source and apparent moisture sink were computed and compared to the kinematic vertical velocity for both real data and the mesoscale analysis and prediction system. Three different case studies of various weathe regimes were examined.
Williams, James P.; Martin, Keith D.; Thomas, Justin R.; Caro, Samuel
2010-01-01
The International Space Station (ISS) Solar Array Management (SAM) software toolset provides the capabilities necessary to operate a spacecraft with complex solar array constraints. It monitors spacecraft telemetry and provides interpretations of solar array constraint data in an intuitive manner. The toolset provides extensive situational awareness to ensure mission success by analyzing power generation needs, array motion constraints, and structural loading situations. The software suite consists of several components including samCS (constraint set selector), samShadyTimers (array shadowing timers), samWin (visualization GUI), samLock (array motion constraint computation), and samJet (attitude control system configuration selector). It provides high availability and uptime for extended and continuous mission support. It is able to support two-degrees-of-freedom (DOF) array positioning and supports up to ten simultaneous constraints with intuitive 1D and 2D decision support visualizations of constraint data. Display synchronization is enabled across a networked control center and multiple methods for constraint data interpolation are supported. Use of this software toolset increases flight safety, reduces mission support effort, optimizes solar array operation for achieving mission goals, and has run for weeks at a time without issues. The SAM toolset is currently used in ISS real-time mission operations.
One-Dimensional (1D) ZnS Nanomaterials and Nanostructures
Institute of Scientific and Technical Information of China (English)
Xiaosheng FANG; Lide ZHANG
2006-01-01
One-dimensional (1D) nanomaterials and nanostructures have received much attention due to their potential interest for understanding fundamental physical concepts and for applications in constructing nanoscale electric and optoelectronic devices. Zinc sulfide (ZnS) is an important semiconductor compound of Ⅱ-Ⅵ group,and the synthesis of 1D ZnS nanomaterials and nanostructures has been of growing interest owing to their promising application in nanoscale optoelectronic devices. This paper reviews the recent progress on 1D ZnS nanomaterials and nanostructures, including nanowires, nanowire arrays, nanorods, nanobelts or nanoribbons,nanocables, and hierarchical nanostructures etc. This article begins with a survey of various methods that have been developed for generating 1D nanomaterials and nanostructures, and then mainly focuses on structures,synthesis, characterization, formation mechanisms and optical property tuning, and luminescence mechanisms of 1D ZnS nanomaterials and nanostructures. Finally, this review concludes with personal views towards future research on 1D ZnS nanomaterials and nanostructures.
Analysis list: Nr1d2 [Chip-atlas[Archive
Lifescience Database Archive (English)
Full Text Available Nr1d2 Liver + mm9 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Nr1d2.1.tsv... http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Nr1d2.5.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Nr1d2....10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Nr1d2.Liver.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Liver.gml ...
Metastable states and information propagation in a 1D array of locally-coupled bistable cells
Anantram, M. P.; Roychowdhury, Vwani P.
1998-01-01
We study the effect of metastable states on the relaxation process (and hence information propagation) in locally coupled and boundary-driven structures. We first give a general argument to show that metastable states are inevitable even in the simplest of structures, a wire. At finite temperatures, the relaxation mechanism is a thermally assisted random walk. The time required to reach the ground state and its life time are determined by the coupling parameters. These time scales are studied...
Energy Technology Data Exchange (ETDEWEB)
Popovic, Marta; Zaja, Roko [Laboratory for Molecular Ecotoxicology, Division for Marine and Environmental Research, Rudjer Boskovic Institute, Bijenicka 54, 10 000 Zagreb (Croatia); Fent, Karl [University of Applied Sciences Northwestern Switzerland, School of Life Sciences, Gründenstrasse 40, CH-4132 Muttenz (Switzerland); Swiss Federal Institute of Technology (ETH Zürich), Department of Environmental System Sciences, Institute of Biogeochemistry and Pollution Dynamics, CH-8092 Zürich (Switzerland); Smital, Tvrtko, E-mail: smital@irb.hr [Laboratory for Molecular Ecotoxicology, Division for Marine and Environmental Research, Rudjer Boskovic Institute, Bijenicka 54, 10 000 Zagreb (Croatia)
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
International Nuclear Information System (INIS)
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
Finite element analysis of underwater capacitor micromachined ultrasonic transducers.
Roh, Yongrae; Khuri-Yakub, Butrus T
2002-03-01
A simple electro-mechanical equivalent circuit model is used to predict the behavior of capacitive micromachined ultrasonic transducers (cMUT). Most often, cMUTs are made in silicon and glass plates that are in the 0.5 mm to 1 mm range in thickness. The equivalent circuit model of the cMUT lacks important features such as coupling to the substrate and the ability to predict cross-talk between elements of an array of transducers. To overcome these deficiencies, a flnite element model of the cMUT is constructed using the commercial code ANSYS. Calculation results of the complex load impedance seen by single capacitor cells are presented, then followed by a calculation of the plane wave real load impedance seen by a parallel combination of many cells that are used to make a transducer. Cross-talk between 1-D array elements is found to be due to two main sources: coupling through a Stoneley wave propagating at the transducer-water interface and coupling through Lamb waves propagating in the substrate. To reduce the cross-talk level, the effect of structural variations of the substrate are investigated, which includes a change of its thickness and etched trenches or polymer walls between array elements. PMID:12322877
The Gain Properties of 1-D Active Photonic Crystal
Institute of Scientific and Technical Information of China (English)
无
2003-01-01
The terminology 'ID frequency'(w ID) is proposed after analyzing the 1D active photonic crystal based on the transfer matrix method. The relationship between wID and the structure parameters of the photonic crystal is investigated.
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
TBC1D24 genotype–phenotype correlation
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
1D photonic crystal sensor integrated in a microfluidic system
DEFF Research Database (Denmark)
Nunes, Pedro; Mortensen, Asger; Kutter, Jörg Peter; Mogensen, Klaus Bo
2009-01-01
A refractive index sensor was designed as a 1D resonator incorporated in a microfluidic channel, where aqueous solutions were injected. A sensitivity of 480 nm/RIU and a minimum difference of Deltan = 0.002 were determined.......A refractive index sensor was designed as a 1D resonator incorporated in a microfluidic channel, where aqueous solutions were injected. A sensitivity of 480 nm/RIU and a minimum difference of Deltan = 0.002 were determined....
Supported plasma-made 1D heterostructures: perspectives and applications
Borras, Ana; Macias-Montero, Manuel; Romero-Gomez, Pablo; Gonzalez-Elipe, Agustin R
2011-01-01
Abstract Plasma related methods have been widely used in the fabrication of carbon nanotubes and nanofibres and semiconducting inorganic nanowires. A natural progression of the research in the field of 1D nanostructures is the synthesis of multicomponent nanowires and nanofibres. In this article we review the state of the art of the fabrication by plasma methods of 1D heterostructures including applications and perspectives. Furthermore, recent developments on the use of metal seeds (Ag, A...
Unveiling the Role of CNTs on the Phase Formation of 1D Ferroelectrics
Mahajan, Amit
2015-05-21
Carbon nanotubes (CNTs) have the potential to act as templates or bottom electrodes for three dimension (3D) capacitor arrays, which utilise one dimension (1D) ferroelectric nanostructures to increase memory size and density. However, growing a ferroelectric on the surface of CNTs is non-trivial. Here, we demonstrate that multi-walled (MW) CNTs decrease the time and temperature for formation of lead zirconium titanate Pb(Zr1-xTix)O3 (PZT) by ~100 ºC commensurate with a decrease in activation energy from 68±15 kJ/mol to 27±2 kJ/mol. As a consequence, monophasic PZT was obtained at 575 ºC for MWCNTs/PZT whereas for pure PZT traces of pyrochlore were still present at 650 ºC, where PZT phase formed due to homogeneous nucleation. The piezoelectric nature of MWCNT/PZT synthesised at 500 ºC for 1 h was proved. Although further work is required to prove the concept of 3D capacitor arrays, our result suggests that it is feasible to utilise MWCNTs as templates/electrodes for the formation of 1D PZT nano ferroelectrics.
Tuning the 1D-self-assembly of dicyano-functionalized helicene building-blocks
International Nuclear Information System (INIS)
Full text: Effective control of chirality in supramolecular systems is an important challenge towards the assembly of well-defined nano-architectures from the bottom-up. The chirality transfer from single molecules onto 3D- and 2D-crystals is well known, however chirality in case of the 1D-objects (wires) is largely unexplored. Here we present a study based on Scanning Tunnelling Microscopy (STM) and X-Ray Photoelectron Spectroscopy (XPS) measurements and Density Functional Theory (DFT) calculations to understand the formation of 1D conglomerates from enantiopure dicyano functionalized heptahelicene molecules of both chiralities at different, well defined single-crystal surfaces. We show that the main bonding motif can be switched by temperature, substrate or adatom stimuli. We discuss the key driving forces for the formation of well-ordered long-range arrays and the chirality transfer on the single molecule scale as well as onto the 1D conglomerate as a whole. In comparison of experiment and theory, we deepen the insight into the chirality transfer in competition between molecule-molecule and surface-molecule interactions. (author)
L(d1, d2,..., dt)-Number λ(Cn; d1, d2,...,dt) of Cycles
Institute of Scientific and Technical Information of China (English)
GAO Zhen Bin; ZHANG Xiao Dong
2009-01-01
An L(d1,d2,...,dt)-labeling of a graph G is a function f from its vertex set V(G) to the set {0, 1,..., k} for some positive integer k such that {f(x) - f(y)| ≥ di, if the distance between vertices x and y in G is equal to i for i = 1,2,...,t. The L(d1,d2,...,dt)-number λ(G;d1,d2,... ,dt) of G is the smallest integer number k such that G has an L(d1,d2,... ,dt)labeling with max{f(x)|x ∈ V(G)} = k. In this paper, we obtain the exact values for λ(Cn; 2, 2,1) and λ(Cn; 3, 2, 1), and present lower and upper bounds for λ(Cn; 2,..., 2,1,..., 1)
Resonant indirect exchange in 1D semiconductor nanostructures
International Nuclear Information System (INIS)
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. - Highlights: • A resonant indirect exchange interaction between magnetic centers mediated by a 1D conducting channel is considered. • It is shown that the indirect exchange is strongly enhanced due to resonant tunnel coupling of a magnetic bound state with the delocalized states. • The two cases of quadratic and linear energy dispersion of the 1D free carriers are considered. • Pecularities of the indirect exchange mediated by a carbon nanotube has been investigated
Resonant indirect exchange in 1D semiconductor nanostructures
Energy Technology Data Exchange (ETDEWEB)
Rozhansky, I.V., E-mail: rozhansky@gmail.com [Ioffe Institute, Russian Academy of Sciences, St.Petersburg 194021 (Russian Federation); Lappeenranta University of Technology, P.O. Box 20, FI-53851 Lappeenranta (Finland); St. Petersburg State Polytechnic University, St. Petersburg 195251 (Russian Federation); Krainov, I.V.; Averkiev, N.S. [Ioffe Institute, Russian Academy of Sciences, St.Petersburg 194021 (Russian Federation); Lähderanta, E. [Lappeenranta University of Technology, P.O. Box 20, FI-53851 Lappeenranta (Finland)
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. - Highlights: • A resonant indirect exchange interaction between magnetic centers mediated by a 1D conducting channel is considered. • It is shown that the indirect exchange is strongly enhanced due to resonant tunnel coupling of a magnetic bound state with the delocalized states. • The two cases of quadratic and linear energy dispersion of the 1D free carriers are considered. • Pecularities of the indirect exchange mediated by a carbon nanotube has been investigated.
Iris Feature Extraction Method Based on 1D Gabor Filter
Institute of Scientific and Technical Information of China (English)
XU Guang-zhu; MA Yi-de; ZHANG Zai-feng
2008-01-01
The normalized iris image was divided into eight sub-bands, and every column of each sub-band was averaged by rows to generate eight 1D iris signals. Then the even symmetry item of 1D Gabor filter was used to describe local characteristic blocks in 1D iris signals, and the results were quantified by their polarities to generate iris codes. In order to estimate the performance of the presented method, an iris recognition platform was produced and the Hamming distance between two iris codes was computed to measure the dissimilarity of them. The experimental results in CASIA v1 0 and Bath iris image databases show that the proposed iris feature extraction algorithm has a promising potential in iris recognition.
Nonreciprocity of edge modes in 1D magnonic crystal
Energy Technology Data Exchange (ETDEWEB)
Lisenkov, I., E-mail: ivan.lisenkov@phystech.edu [Kotelnikov Institute of Radio-engineering and Electronics of RAS, 11-7 Mokhovaya st., Moscow 125009 (Russian Federation); Department of Physics, Oakland University, 2200 N. Squirrel Rd., Rochester, MI 48309 (United States); Moscow Institute of Physics and Technology, 9 Instituskij per., Dolgoprudny, 141700, Moscow Region (Russian Federation); Kalyabin, D., E-mail: dmitry.kalyabin@phystech.edu [Kotelnikov Institute of Radio-engineering and Electronics of RAS, 11-7 Mokhovaya st., Moscow 125009 (Russian Federation); Moscow Institute of Physics and Technology, 9 Instituskij per., Dolgoprudny, 141700, Moscow Region (Russian Federation); Osokin, S. [Kotelnikov Institute of Radio-engineering and Electronics of RAS, 11-7 Mokhovaya st., Moscow 125009 (Russian Federation); Moscow Institute of Physics and Technology, 9 Instituskij per., Dolgoprudny, 141700, Moscow Region (Russian Federation); Klos, J.W.; Krawczyk, M. [Adam Mickiewicz University in Poznan, Umultowska 85, Poznan 61-614 (Poland); Nikitov, S., E-mail: nikitov@cplire.ru [Kotelnikov Institute of Radio-engineering and Electronics of RAS, 11-7 Mokhovaya st., Moscow 125009 (Russian Federation); Moscow Institute of Physics and Technology, 9 Instituskij per., Dolgoprudny, 141700, Moscow Region (Russian Federation); Saratov State University, 112 Bol' shaya Kazach' ya, Saratov 410012 (Russian Federation)
2015-03-15
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. - Highlights: • Magnetostatic surface spin waves in 1D magnonic crystals were studied theoretically. • Mathematical model is based on plane wave method. • Mathematical model was applied to different types of magnonic crystals. • Stop band formation and nonreciprocity were obtained.
Nonreciprocity of edge modes in 1D magnonic crystal
International Nuclear Information System (INIS)
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. - Highlights: • Magnetostatic surface spin waves in 1D magnonic crystals were studied theoretically. • Mathematical model is based on plane wave method. • Mathematical model was applied to different types of magnonic crystals. • Stop band formation and nonreciprocity were obtained
1D antiferromagnetism in spin‐alternating bimetallic chains
Coronado Miralles, Eugenio; Sapiña Navarro, Fernando; Drillon, M.; De Jongh, L.J.
1990-01-01
The magnetic and thermal properties of the ordered bimetallic chain CoNi(EDTA)⋅6H2O in the very low‐temperature range are reported. The magnetic behavior does not exhibit the characteristic features of 1D ferrimagnets, but a continuous decrease of χmT towards zero at absolute zero. This 1D antiferromagnetic behavior results from an accidental compensation between the moments located at the two sublattices. This behavior, as well as the specific‐heat results, are modeled on the basis of an Isi...
GIS-BASED 1-D DIFFUSIVE WAVE OVERLAND FLOW MODEL
Energy Technology Data Exchange (ETDEWEB)
KALYANAPU, ALFRED [Los Alamos National Laboratory; MCPHERSON, TIMOTHY N. [Los Alamos National Laboratory; BURIAN, STEVEN J. [NON LANL
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.
Quantum electrodynamics with 1D arti cial atoms
DEFF Research Database (Denmark)
Javadi, Alisa
A 1D atom, a single quantum emitter coupled to a single optical mode, exhibits rich quantum electrodynamic (QED) e_ects and is thought to be the key ingredient for many applications in quantuminformation processing. Single quantum dots (QD) in photonic-crystal waveguides (PCW) constitute a robust...... photons as expected from the theory. The value of g(2)(0) is around 1.08. The results con_rm the observation of an on-chip giant optical nonlinearity and the 1D atom behavior. Another direction in this thesis has been to investigate the e_ect of Anderson localization on the electrodynamics of QDs in PCWs...
Array tomography: imaging stained arrays.
Micheva, Kristina D; O'Rourke, Nancy; Busse, Brad; Smith, Stephen J
2010-11-01
Array tomography is a volumetric microscopy method based on physical serial sectioning. Ultrathin sections of a plastic-embedded tissue are cut using an ultramicrotome, bonded in an ordered array to a glass coverslip, stained as desired, and imaged. The resulting two-dimensional image tiles can then be reconstructed computationally into three-dimensional volume images for visualization and quantitative analysis. The minimal thickness of individual sections permits high-quality rapid staining and imaging, whereas the array format allows reliable and convenient section handling, staining, and automated imaging. Also, the physical stability of the arrays permits images to be acquired and registered from repeated cycles of staining, imaging, and stain elution, as well as from imaging using multiple modalities (e.g., fluorescence and electron microscopy). Array tomography makes it possible to visualize and quantify previously inaccessible features of tissue structure and molecular architecture. However, careful preparation of the tissue is essential for successful array tomography; these steps can be time-consuming and require some practice to perfect. In this protocol, tissue arrays are imaged using conventional wide-field fluorescence microscopy. Images can be captured manually or, with the appropriate software and hardware, the process can be automated. PMID:21041399
Array tomography: production of arrays.
Micheva, Kristina D; O'Rourke, Nancy; Busse, Brad; Smith, Stephen J
2010-11-01
Array tomography is a volumetric microscopy method based on physical serial sectioning. Ultrathin sections of a plastic-embedded tissue are cut using an ultramicrotome, bonded in an ordered array to a glass coverslip, stained as desired, and imaged. The resulting two-dimensional image tiles can then be reconstructed computationally into three-dimensional volume images for visualization and quantitative analysis. The minimal thickness of individual sections permits high-quality rapid staining and imaging, whereas the array format allows reliable and convenient section handling, staining, and automated imaging. Also, the physical stability of the arrays permits images to be acquired and registered from repeated cycles of staining, imaging, and stain elution, as well as from imaging using multiple modalities (e.g., fluorescence and electron microscopy). Array tomography makes it possible to visualize and quantify previously inaccessible features of tissue structure and molecular architecture. However, careful preparation of the tissue is essential for successful array tomography; these steps can be time consuming and require some practice to perfect. This protocol describes the sectioning of embedded tissues and the mounting of the serial arrays. The procedures require some familiarity with the techniques used for ultramicrotome sectioning for electron microscopy. PMID:21041397
Nonlinear ac conductivity of interacting 1d electron systems
Rosenow, Bernd; Nattermann, Thomas
2004-01-01
We consider low energy charge transport in one-dimensional (1d) electron systems with short range interactions under the influence of a random potential. Combining RG and instanton methods, we calculate the nonlinear ac conductivity and discuss the crossover between the nonanalytic field dependence of the electric current at zero frequency and the linear ac conductivity at small electric fields and finite frequency.
A 1D wavelet filtering for ultrasound images despeckling
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.
Quantitative 1D saturation profiles on chalk by NMR
DEFF Research Database (Denmark)
Olsen, Dan; Topp, Simon; Stensgaard, Anders;
1996-01-01
Quantitative one-dimensional saturation profiles showing the distribution of water and oil in chalk core samples are calculated from NMR measurements utilizing a 1D CSI spectroscopy pulse sequence. Saturation profiles may be acquired under conditions of fluid flow through the sample. Results reveal...
Large Time existence For 1D Green-Naghdi equations
Israwi, Samer
2009-01-01
We consider here the $1D $ Green-Naghdi equations that are commonly used in coastal oceanography to describe the propagation of large amplitude surface waves. We show that the solution of the Green-Naghdi equations can be constructed by a standard Picard iterative scheme so that there is no loss of regularity of the solution with respect to the initial condition.
Lifescience Database Archive (English)
Full Text Available 1D6R 大豆 Soybean Glycine max (L.) Merrill Bowman-Birk Type Proteinase Inhibitor Precursor Glyci ... Warkentin, G.Wenzl, P.Flecker Crystal Structure Of Cancer ... Chemopreventive Bowman-Birk Inhibitor In Ternary C ...
Simulation of Organic Solar Cells Using AMPS-1D Program
Directory of Open Access Journals (Sweden)
Samah G. Babiker
2012-03-01
Full Text Available The analysis of microelectronic and photonic structure in one dimension program [AMPS-1D] program has been successfully used to study inorganic solar cells. In this work the program has been used to optimize the performance of the organic solar cells. The cells considered consist of poly(2-methoxy-5-(3,7- dimethyloctyloxy-1,4-phenylenevinylene [MDMO-PPV
NEW FEATURES OF HYDRUS-1D, VERSION 3.0
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...
Optical properties of LEDs with patterned 1D photonic crystal
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.
Scattering approach to classical quasi-1D transport
Kogan, Eugene
1996-01-01
General dynamical transport of classical particles in disordered quasi-1D samples is viewed in the framework of scattering approach. Simple equation for the transfer-matrix is obtained within this unified picture. In the case of diffusive transport the solution of this equation exactly coincides with the solution of diffusion equation.
Bessel Series in the Space H1(D)%H1(D)空间的Bessel级数
Institute of Scientific and Technical Information of China (English)
木乐华
2001-01-01
An identity concerning the partial sums of Bessel series and power series for H1(D) functions is given.Based on it,many of precise extimates about the deviation of the partial sums of Bessel series can be obtained.%本文给出关于H1(D)空间中函数的Bessel级数的部分和用幂级数的部分和表示的一个恒等式.基于它，可以得到Bessel级数部分和偏差的诸多精确估计.
3-D Imaging Using Row-Column-Addressed Arrays With Integrated Apodization
DEFF Research Database (Denmark)
Christiansen, Thomas Lehrmann; Rasmussen, Morten Fischer; Bagge, Jan Peter;
2015-01-01
This paper demonstrates the fabrication, characterization, and experimental imaging results of a 62+62 element λ/2-pitch row-column-addressed capacitive micromachined ultrasonic transducer (CMUT) array with integrated apodization. A new fabrication process was used to manufacture a 26.3 mm by 26......Pa, and the sensitivity was 0.299 ± 0.090 V/Pa. The nearest neighbor crosstalk level was -23.9 ± 3.7 dB, while the transmit-to-receive-elements crosstalk level was -40.2 ± 3.5 dB. Imaging of a 0.3-mm-diameter steel wire using synthetic transmit focusing with 62 single-element emissions demonstrated axial and lateral...... FWHMs of 0.71 mm and 1.79 mm (f-number: 1.4), respectively, compared with simulated axial and lateral FWHMs of 0.69 mm and 1.76 mm. The dominant ghost echo was reduced by 15.8 dB in measurements using the integrated apodization compared with the disabled configuration. The effect was reproduced...
1D3V PIC simulation of propagation of relativistic electron beam in an inhomogeneous plasma
Shukla, Chandrashekhar; Patel, Kartik
2015-01-01
A recent experimental observation has shown efficient transport of Mega Ampere of electron currents through aligned carbon nanotube arrays [Phys. Rev Letts. 108, 235005 (2012)]. The result was subsequently interpreted on the basis of suppression of the filamentation instability in an inhomogeneous plasma [Phys. Plasmas 21, 012108 (2014)]. This inhomogeneity forms as a result of the ionization of the carbon nanotubes. In the present work a full 1D3V Particle-in-Cell (PIC) simulations have been carried out for the propagation of relativistic electron beams (REB) through an inhomogeneous background plasma. The suppression of the filamentation instability, responsible for beam divergence, is shown. The simulation also confirms that in the nonlinear regime too the REB propagation is better when it propagates through a plasma whose density is inhomogeneous transverse to the beam. The role of inhomogeneity scale length, its amplitude and the transverse beam temperature etc., in the suppression of the instability is ...
On the 1D Coulomb Klein-Gordon equation
International Nuclear Information System (INIS)
For a single particle of mass m experiencing the potential -α/vertical bar x vertical bar, the 1D Klein-Gordon equation is mathematically underdefined even when α 2 the ground-state energy E decreases through zero, and soon after that mR reaches a finite critical value below which E becomes complex, signalling a breakdown of the single-particle theory. At this critical point of the curve E(mR) the Klein-Gordon norm changes sign: the curve has a lower branch describing a bound antiparticle state, with positive energy -E, which exists for mR between the critical and some higher value where E reaches -m. Though apparently unanticipated in this context, similar scenarios are in fact familiar for strong short-range potentials (1D or 3D), and also for strong 3D Coulomb potentials with α of order unity
Fuzzball solutions and D1-D5 microstates
Skenderis, K; Skenderis, Kostas; Taylor, Marika
2006-01-01
We revisit the relation between fuzzball solutions and D1-D5 microstates. A consequence of the fact that the RR ground states (in the usual basis) are eigenstates of the R-charge is that only neutral operators can have non-vanishing expectation values on these states. We compute the holographic 1-point functions of the fuzzball solutions and find that charged chiral primaries have non-zero expectation values, except when the curve characterizing the solution is circular. The non-zero vevs reflect the fact that a generic curve breaks R-symmetry completely. This implies that fuzzball solutions (excepting circular ones) can only correspond to superpositions of RR states. We construct new solutions by appropriately superimposing fuzzball solutions that have vanishing vevs for all charged chiral primary operators and can therefore correspond to D1-D5 microstates.
D1-D5-P microstates at the cap
Giusto, Stefano; Mathur, Samir D; Turton, David
2012-01-01
The geometries describing D1-D5-P bound states in string theory have three regions: flat asymptotics, an anti-de Sitter throat, and a 'cap' region at the bottom of the throat. We identify the CFT description of a known class of supersymmetric D1-D5-P microstate geometries which describe degrees of freedom in the cap region. The class includes both regular solutions and solutions with conical defects, and generalizes configurations with known CFT descriptions: a parameter related to spectral flow in the CFT is generalized from integer to fractional values. We provide strong evidence for this identification by comparing the massless scalar excitation spectrum between gravity and CFT and finding exact agreement.
Waves in a 1D electrorheological dusty plasma lattice
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.
Dentin dysplasia type 1d: A rare case
Sujit Ranjan Sahoo; Sonia Aggarwal
2014-01-01
Dentin dysplasia is a rare hereditary disturbance of dentin formation characterized by a defective dentin development with clinically normal-appearing crowns, severe hypermobility of teeth and spontaneous dental abscesses or cysts. Radiographic analysis shows obliteration of all pulp chambers by pulp stones, short, blunted and malformed or absent roots, peri-apical radiolucencies of noncarious teeth. We present a case of dentin dysplasia type 1d in a 19-year-old boy along with the clinical, r...
Blind Detection of Severely Blurred 1D Barcode
Dridi, Noura; Delignon, Yves; Sawaya, Wadih; Septier, François
2010-01-01
In this paper, we present a joint blind channel estimation and symbol detection for decoding a blurred and noisy 1D barcode captured image. From an information transmission point of view, we show that the channel impulse response, the noise power and the symbols can be efficiently estimated by taking into account the signal structure such as the cyclostationary property of the hidden Markov process to estimate. Based on the Expectation-Maximisation method, we show that the new algorithm offer...
A study of slow light in 1D photonic crystals
Yudistira, D.; Hoekstra, H.J.W.M.; Hammer, M; Marpaung, D.A.I.
2005-01-01
Slow light (SL) states corresponding to wavelength regions near the bandgap edge of grating structure are known to show strong field enhancement. Such states may be excited efficiently by well-optimised adiabatic transitions in such structures, e.g., by slowly turning on the modulation depth. To study adiabatic excitations, a detailed research in 1D is performed to obtain insight into the relation between the device parameters and properties like enhancement and modal reflection. The results ...
Theory of slow light excitation in 1D photonic crystals
Yudistira, D.; Marpaung, D.A.I.; Handoyo, H.P.; Hoekstra, H.J.W.M.; Hammer, M; Tjia, M.O.; Iskandar, A.A.
2004-01-01
Slow light (SL) states corresponding to wavelength regions near the bandgap edge of grated structures are known to show strong eld enhancement. Such states may be excited efciently by well-optimised adiabatic transitions in grating structures, e.g., by slowly turning on the modulation depth. To study adiabatic excitations, a detailed investigation in 1D is performed to obtain insight into the relation between the device parameters and properties like eld enhancement and modal reection. The re...
Development of 1D Liner Compression Code for IDL
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.
Coupling of Nod1D and HOTCHANNEL: static case
International Nuclear Information System (INIS)
In this work the joining of the programs Nod1D and HOTCHANNEL, developed in the National Polytechnic Institute (IPN) and in the Electrical Research Institute (IIE) respectively is described. The first one allows to study the neutronic of a nuclear reactor and the second one allows to carry out the analysis of hot channel of a Boiling Water Reactor (BWR). Nod1 D is a program that it solves by nodal methods type finite element those diffusion equations in multigroup, and it is the static part of Nod Kin that it solves the diffusion equation in their time dependent part. For another side HOTCHANNEL is based on a mathematical model constituted by four conservation equations (two of mass conservation, one of motion quantity and one of energy), which are solved applying one discretization in implicit finite differences. Both programs have been verified in independent form using diverse test problems. In this work the modifications that were necessary to carry out to both for obtaining a coupled program that it provides the axial distribution of the neutron flux, the power, the burnup and the void fraction, among others parameters as much as neutronic as thermal hydraulics are described. Those are also mentioned limitations, advantages and disadvantages of the final product to which has been designated Nod1 D-HotChn. Diverse results for the Cycle 1 of the Laguna Verde Unit 1 reactor of the Nucleo electric central comparing them with those obtained directly with the CoreMasterPresto code are provided. (Author)
MARG1D: One dimensional outer region matching data code
International Nuclear Information System (INIS)
A code MARG1D has been developed which computes outer region matching data of the one dimensional Newcomb equation. Matching data play an important role in the resistive (and non ideal) Magneto-hydrodynamic (MHD) stability analysis in a tokamak plasma. The MARG1D code computes matching data by using the boundary value method or by the eigenvalue method. Variational principles are derived for the problems to be solved and a finite element method is applied. Except for the case of marginal stability, the eigenvalue method is equivalent to the boundary value method. However, the eigenvalue method has the several advantages: it is a new method of ideal MHD stability analysis for which the marginally stable state can be identified, and it guarantees numerical stability in computing matching data close to marginal stability. We perform detailed numerical experiments for a model equation with analytical solutions and for the Newcomb equation in the m=1 mode theory. Numerical experiments show that MARG1D code gives the matching data with numerical stability and high accuracy. (author)
Supported plasma-made 1D heterostructures: perspectives and applications
Borras, Ana; Macias-Montero, Manuel; Romero-Gomez, Pablo; Gonzalez-Elipe, Agustin R.
2011-05-01
Plasma-related methods have been widely used in the fabrication of carbon nanotubes and nanofibres (NFs) and semiconducting inorganic nanowires (NWs). A natural progression of the research in the field of 1D nanostructures is the synthesis of multicomponent NWs and NFs. In this paper we review the state of the art of the fabrication by plasma methods of 1D heterostructures including applications and perspectives. Furthermore, recent developments on the use of metal seeds (Ag, Au, Pt) to obtain metal@oxide nanostructures are also extensively described. Results are shown for various metal substrates, either metal foils or supported nanoparticles/thin films of the metal where the effects of the size, surface coverage, percolation degree and thickness of the metal seeds have been systematically evaluated. The possibilities of the process are illustrated by the preparation of nanostructured films and supported NFs of different metal@oxides (Ag, Au and SiO2, TiO2, ZnO). Particularly, in the case of silver, the application of an oxygen plasma treatment prior to the deposition of the oxide was critical for efficiently controlling the growth of the 1D heterostructures. A phenomenological model is proposed to account for the thin-film nanostructuring and fibre formation by considering basic phenomena such as stress relaxation, inhomogeneities in the plasma sheath electrical field and the local disturbance of the oxide growth.
Supported plasma-made 1D heterostructures: perspectives and applications
International Nuclear Information System (INIS)
Plasma-related methods have been widely used in the fabrication of carbon nanotubes and nanofibres (NFs) and semiconducting inorganic nanowires (NWs). A natural progression of the research in the field of 1D nanostructures is the synthesis of multicomponent NWs and NFs. In this paper we review the state of the art of the fabrication by plasma methods of 1D heterostructures including applications and perspectives. Furthermore, recent developments on the use of metal seeds (Ag, Au, Pt) to obtain metal-oxide nanostructures are also extensively described. Results are shown for various metal substrates, either metal foils or supported nanoparticles/thin films of the metal where the effects of the size, surface coverage, percolation degree and thickness of the metal seeds have been systematically evaluated. The possibilities of the process are illustrated by the preparation of nanostructured films and supported NFs of different metal-oxides (Ag, Au and SiO2, TiO2, ZnO). Particularly, in the case of silver, the application of an oxygen plasma treatment prior to the deposition of the oxide was critical for efficiently controlling the growth of the 1D heterostructures. A phenomenological model is proposed to account for the thin-film nanostructuring and fibre formation by considering basic phenomena such as stress relaxation, inhomogeneities in the plasma sheath electrical field and the local disturbance of the oxide growth.
Domain walls and instantons in N=1, d=4 supergravity
Huebscher, M; Ortin, T
2009-01-01
We study the supersymmetric sources of (multi-) domain-wall and (multi-) instanton solutions of generic N=1, d=4 supergravities, that is: the worldvolume effective actions for said supersymmetric topological defects. The domain-wall solutions naturally couple to the two 3-forms recently found as part of the N=1, d=4 tensor hierarchy (i.e. they have two charges in general) and their tension is the absolute value of the superpotential section L. The introduction of sources (we study sources with finite and vanishing thickness) is equivalent to the introduction of local coupling constants and results in dramatic changes of the solutions. Our results call for a democratic reformulation of N=1,d=4 supergravity in which coupling constants are, off-shell, scalar fields. The effective actions for the instantons are always proportional to the coordinate orthogonal to the twist-free embedding of the null-geodesic (in the Wick-rotated scalar manifold) describing the instanton. We show their supersymmetry and find the as...
Examining Prebiotic Chemistry Using O(^1D) Insertion Reactions
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.
Coupling of Nod1D and HOTCHANNEL: static case; Acoplamiento de Nod1D y HOTCHANNEL: caso estatico
Energy Technology Data Exchange (ETDEWEB)
Gomez T, A.M. [IPN-ESFM, 07738 Mexico D.F. (Mexico); Ovando C, R. [IIE-Gcia. de Energia Nuclear, Cuernavaca, Morelos (Mexico)]. e-mail: rovando@iie.org.mx
2003-07-01
In this work the joining of the programs Nod1D and HOTCHANNEL, developed in the National Polytechnic Institute (IPN) and in the Electrical Research Institute (IIE) respectively is described. The first one allows to study the neutronic of a nuclear reactor and the second one allows to carry out the analysis of hot channel of a Boiling Water Reactor (BWR). Nod1 D is a program that it solves by nodal methods type finite element those diffusion equations in multigroup, and it is the static part of Nod Kin that it solves the diffusion equation in their time dependent part. For another side HOTCHANNEL is based on a mathematical model constituted by four conservation equations (two of mass conservation, one of motion quantity and one of energy), which are solved applying one discretization in implicit finite differences. Both programs have been verified in independent form using diverse test problems. In this work the modifications that were necessary to carry out to both for obtaining a coupled program that it provides the axial distribution of the neutron flux, the power, the burnup and the void fraction, among others parameters as much as neutronic as thermal hydraulics are described. Those are also mentioned limitations, advantages and disadvantages of the final product to which has been designated Nod1 D-HotChn. Diverse results for the Cycle 1 of the Laguna Verde Unit 1 reactor of the Nucleo electric central comparing them with those obtained directly with the CoreMasterPresto code are provided. (Author)
Extended-Range Ultrarefractive 1D Photonic Crystal Prisms
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
BGK electron solitary waves: 1D and 3D
Directory of Open Access Journals (Sweden)
L.-J. Chen
2002-01-01
Full Text Available This paper presents new results for 1D BGK electron solitary wave (phase-space electron hole solutions and, based on the new results, extends the solutions to include the 3D electrical interaction (E ~ 1/r 2 of charged particles. Our approach for extending to 3D is to solve the nonlinear 3D Poisson and 1D Vlasov equations based on a key feature of 1D electron hole (EH solutions; the positive core of an EH is screened by electrons trapped inside the potential energy trough. This feature has not been considered in previous studies. We illustrate this key feature using an analytical model and argue that the feature is independent of any specific model. We then construct azimuthally symmetric EH solutions under conditions where electrons are highly field-aligned and ions form a uniform background along the magnetic field. Our results indicate that, for a single humped electric potential, the parallel cut of the perpendicular component of the electric field (E⊥ is unipolar and that of the parallel component (E|| bipolar, reproducing the multi-dimensional features of the solitary waves observed by the FAST satellite. Our analytical solutions presented in this article capture the 3D electric interaction and the observed features of (E|| and E⊥. The solutions predict a dependence of the parallel width-amplitude relation on the perpendicular size of EHs. This dependence can be used in conjunction with experimental data to yield an estimate of the typical perpendicular size of observed EHs; this provides important information on the perpendicular span of the source region as well as on how much electrostatic energy is transported by the solitary waves.
Coherent thermal conductance of 1-D photonic crystals
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.
Spatial coherence of polaritons in a 1D channel
Energy Technology Data Exchange (ETDEWEB)
Savenko, I. G., E-mail: savenko.j@mail.ru [Russian Academy of Sciences, Academic University, Research and Education Center of Nanotechnologies (Russian Federation); Iorsh, I. V. [National Research University of Information Technologies, Mechanics and Optics (Russian Federation); Kaliteevski, M. A. [Russian Academy of Sciences, Academic University, Research and Education Center of Nanotechnologies (Russian Federation); Shelykh, I. A. [University of Iceland, Science Institute (Iceland)
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.
A Godunov method for Lagrangian hydrodynamics in 1D
Energy Technology Data Exchange (ETDEWEB)
Crowley, W.P.
1987-01-15
For transient problems involving strong shocks, the artificial viscosity method has been the standard in numerical hydrodynamics for many years. An alternative approach was suggested by Godunov and it is gaining acceptance. We consider a Godunov method for 1D Lagrangian calculations and show that in the case of a strong shock moving through a nonuniform mesh the Godunov solution is superior to the artificial viscosity solution. For uniform mesh shock problems in spherical geometry the two methods give comparable results. 4 refs., 9 figs.
1D-transport properties of single superconducting lead nanowires
DEFF Research Database (Denmark)
Michotte, S.; Mátéfi-Tempfli, Stefan; Piraux, L.
2003-01-01
nanowire is small enough to ensure a 1D superconducting regime in a wide temperature range below T. The non-zero resistance in the superconducting state and its variation caused by fluctuations of the superconducting order parameter were measured versus temperature, magnetic field, and applied DC current......We report on the transport properties of single superconducting lead nanowires grown by an electrodeposition technique, embedded in a nanoporous track-etched polymer membrane. The nanowires are granular, have uniform diameter of ̃40 nm and a very large aspect ratio (̃500). The diameter of the...
Breakdown of 1D water wires inside Charged Carbon Nanotubes
Pant, Shashank
2016-01-01
Using Molecular Dynamics approach we investigated the structure, dynamics of water confined inside pristine and charged 6,6 carbon nanotubes (CNTs). This study reports the breakdown of 1D water wires and the emergence of triangular faced water on incorporating charges in 6,6 CNTs. Incorporation of charges results in high potential barriers to the flipping of water molecules due to the formation of a large number of hydrogen bonds. The PMF analyses show the presence of ~2 kcal/mol barrier for the movement of water inside pristine CNT and almost negligible barrier in charged CNTs.
Restrained Dark $U(1)_d$ at Low Energies
Correia, F C
2016-01-01
We investigate a spontaneously broken $U(1)_d$ gauge symmetry with a muon-specific dark Higgs. Our first goal is to verify how the presence of a new dark Higgs, $\\phi$, and a dark gauge boson, $V$, can simultaneously face the anomalies from the muon magnetic moment and the proton charge radius. Secondly, by assuming that $V$ must decay to an electron-positron pair, we explore the corresponding parameter space determined with the low energy constraints coming from $ K \\to \\mu X$, electron $(g-2)_e$, $K \\to \\mu \
Phthalocyanine based 1D nanowires for device applications
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.
Coherent thermal conductance of 1-D photonic crystals
International Nuclear Information System (INIS)
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.
A 1D analysis of two high order MOC methods
International Nuclear Information System (INIS)
The work presented here provides two different methods for evaluating angular fluxes along long characteristics. One is based off a projection of the 1D transport equation onto a complete set of Legendre polynomials, while the other uses the 1D integral transport equation to evaluate the angular flux values at specific points along each track passing through a cell. The Moment Long Characteristic (M-LC) method is shown to provide 2(P+1) spatial convergence and significant gains in accuracy with the addition of only a few spatial degrees of freedom. The M-LC method, though, is shown to be ill-conditioned at very high order and for optically thin geometries. The Point Long Characteristic (P-LC) method, while less accurate, significantly improves stability to problems with optically thin cells. The P-LC method is also more flexible, allowing for extra angular flux evaluations along a given track to give a more accurate representation of the shape along each track. This is at the expense of increasing the degrees of freedom of the system, though, and requires an increase in memory storage. This work concludes that both may be used simultaneously within the same geometry to provide the best mix of accuracy and stability possible. (authors)
1-D DCT Using Latency Efficient Floating Point Algorithms
Directory of Open Access Journals (Sweden)
Viswanath Gowd A, Yedukondala Rao V, T. Shanmuganantham
2013-04-01
Full Text Available This paper presents the design of one-dimensional discrete cosine transform (DCT architecture for digital signal processing (DSP applications. DCT is a basic transformation for coding method which converts spatial domain to frequency domain of image. In 1-D DCT operation addition, subtraction, multiplication operations are required. These operations must be accurate, less latency. Floating point operations have dynamic range of representation, more accurate and perform millions of calculations per second. So the floating point operations are used for the above operations. In this floating point adder/subtractor is the most complex operation in a floating-point arithmetic and consists of many variable latency- and area dependent sub-operations. In floating-point addition implementations, latency is the primary performance bottleneck. So different types of floating point adder/subtractor algorithms such as LOD, LOP, Two-path are used to decrease the latency. The trade off is observed in 1-D DCT by changing different types of adders in place of summer. All architectures are designed and implemented using VHDL using Xillinx 13.1software.
Study of 1D Strange Charmed Meson Family Using HQET
Directory of Open Access Journals (Sweden)
Pallavi Gupta
2016-01-01
Full Text Available Recently LHCb predicted spin 1 and spin 3 states Ds1⁎(2860 and Ds3⁎(2860 which are studied through their strong decays and are assigned to fit the 13D1 and 13D3 states in the charm spectroscopy. In this paper, using the heavy quark effective theory, we state that assigning Ds1⁎(2860 as the mixing of 13D1-23S1 states is rather a better justification to its observed experimental values than a pure state. We study its decay modes variation with hadronic coupling constant gxh and the mixing angle θ. We appoint spin 3 state Ds3⁎(2860 as the missing 1D 3-JP state and also study its decay channel behavior with coupling constant gyh. To appreciate the above results, we check the variation of decay modes for their spin partners states, that is, 1D2 and 1D2′, with their masses and strong coupling constant, that is, gxh and gyh. Our calculation using HQET approach gives mixing angle of the 13D1-23S1 state for Ds1⁎(2860 to lie in the range (-1.6 radians ≤θ≤-1.2 radians. Our calculation for coupling constant values gives gxh to lie within value range of 0.17–0.20 and gyh to be 0.40. We expect from experiments to observe this mixing angle to verify our results.
Modeling atrazine transport in soil columns with HYDRUS-1D
Directory of Open Access Journals (Sweden)
John Leju CELESTINO LADU
2011-09-01
Full Text Available Both physical and chemical processes affect the fate and transport of herbicides. It is useful to simulate these processes with computer programs to predict solute movement. Simulations were run with HYDRUS-1D to identify the sorption and degradation parameters of atrazine through calibration from the breakthrough curves (BTCs. Data from undisturbed and disturbed soil column experiments were compared and analyzed using the dual-porosity model. The study results show that the values of dispersivity are slightly lower in disturbed columns, suggesting that the more heterogeneous the structure is, the higher the dispersivity. Sorption parameters also show slight variability, which is attributed to the differences in soil properties, experimental conditions and methods, or other ecological factors. For both of the columns, the degradation rates were similar. Potassium bromide was used as a conservative non-reactive tracer to characterize the water movement in columns. Atrazine BTCs exhibited significant tailing and asymmetry, indicating non-equilibrium sorption during solute transport. The dual-porosity model was verified to best fit the BTCs of the column experiments. Greater or lesser concentration of atrazine spreading to the bottom of the columns indicated risk of groundwater contamination. Overall, HYDRUS-1D successfully simulated the atrazine transport in soil columns.
The Cosmological Mass Function with 1D Gravity
Monaco, P; Monaco, Pierluigi; Murante, Giuseppe
1999-01-01
The cosmological mass function problem is analyzed in full detail in the case of 1D gravity, with analytical, semi-analytical and numerical techniques. The extended Press & Schechter theory is improved by detailing the relation between smoothing radius and mass of the objects. This is done by introducing in the formalism the concept of a growth curve for the objects. The predictions of the extended Press & Schechter theory are compared to large N-body simulations of flat expanding 1D universes with scale-free power spectra of primordial perturbations. The collapsed objects in the simulations are located with a clump-finding algorithm designed to find regions that have undergone orbit crossing or that are in the multi-stream regime (these are different as an effect of the finite size of the multi-stream regions). It is found that the semi-analytical mass function theory, which has no free parameters, is able to recover the properties of collapsed objects both statistically and object by object. In part...
Hamming Distance and Data Compression of 1-D CA
Directory of Open Access Journals (Sweden)
Raied Salman
2013-05-01
Full Text Available In this paper an application of von Neumann correct ion technique to the output string of some chaotic rules of 1-D Cellular Automata that are uns uitable for cryptographic pseudo random number generation due to their non uniform distribu tion of the binary elements is presented. The one dimensional (1-D Cellular Automata (CA Ru le space will be classified by the time run of Hamming Distance (HD. This has the advantage of determining the rules that have short cycle lengths and therefore deemed to be unsuitable for cryptographic pseudo random number generation. The data collected from evolution of ch aotic rules that have long cycles are subjected to the original von Neumann density corre ction scheme as well as a new generalized scheme presented in this paper and tested for stati stical testing fitness using Diehard battery of tests. Results show that significant improvement in the statistical tests are obtained when the output of a balanced chaotic rule are mutually excl usive ORed with the output of unbalanced chaotic rule that have undergone von Neumann densit y correction.
COLUMN, 1-D Migration for Various Physical Chemical Processes
International Nuclear Information System (INIS)
1 - Description of problem or function: COLUMN2 is designed for studies of the effects various physicochemical processes on migration in one dimension. It solves the transport equation and can take into account dispersion, sorption, ion exchange, first and second order homogeneous chemical reactions. Spatial variations of input pulses and retention factors are possible. 2 - Method of solution: The Method of solution is based on a finite difference discretion followed by the application of the method of characteristics and two separate grid systems. 3 - Restrictions on the complexity of the problem: For computational reasons the number of components has been limited to 5 and the maximum number of second order reactions is 10. However, a re-dimensioning of all relevant arrays will allow for any number of components and reactions desired. Arrays should never be dimensioned larger than needed in order to save computation time. Five components and 10 second order reactions may seem a small number. However, larger simulations are often divided into smaller sub-problems for clarification purposes. The maximum number of grid points, default value 801, may be enlarged to re-dimensioning all relevant arrays
Institute of Scientific and Technical Information of China (English)
CHEN Chao; YANG Yu-lin; LI Wei-sheng; LIU Yun-ling; YI Zhuo; GUO Yang-hong; PANG Wen-qin
2005-01-01
The transformation of titanium phosphate from 1-D chiral- chain(JTP-A) to 2-D layer(TP-J1) has been carefully investigated. Through a hydrolysis-condensation self-assembly pathway, the crystals of TP-J1 can be obtained from the JTP-A phase under hydrothermal conditions. An intermediate material with zigzag chain during the transformation was observed by XRD characterization. A hypothesis of the transformation mechanism is also described in this article. It is noteworthy that ethylenediamine plays an important role in the transformation.
Simplified 1D modelling of the HGA test
International Nuclear Information System (INIS)
Document available in extended abstract form only. The HGA test is located in the Mont Terri Rock Laboratory (Switzerland). It consists of a horizontal borehole of 1.00 m of diameter and 13.00 m of length excavated in the ultra-low permeable Opalinus clay. During the tunnel drilling, the Opalinus clay near the tunnel wall was damaged, giving rise to an EDZ (Excavation Damaged Zone) around the tunnel. A steel liner was placed along the 6.00 m close to the tunnel mouth in order to guarantee the stability. The last 4.00 m at the tunnel end were backfilled with gravel. Along the remaining 3.00 m, an inflatable rubber packer of 1.00 m in diameter, was installed and inflated, thereby compressing the EDZ that was created during the tunnel excavation. The test section was filled with de-aired water and care was taken in order to eliminate the air from this tunnel section. Subsequently, a series of water and gas injection tests were carried out with varying mega-packer pressure, whereby water or gas was injected into the test section and, due to the very low permeability of the intact Opalinus clay, forced to flow back along the EDZ. In order to model the water and gas flow through the EDZ, we have followed a two-track approach. On the one hand, a 2D axisymmetric numerical model using code-bright has been made. On the other hand, a 1D analytical-numerical model has been developed and implemented in an Excel spreadsheet, whereby the field equations defined on a 1D geometrical domain are numerically solved using the finite element method. The 1D model has been used in order to calibrate the 2D axisymmetric model. Both the Opalinus clay and the EDZ will be considered to be porous media, with an incompressible solid phase (clay), an incompressible liquid phase (water and air) and a gas phase (water and air). The properties of the liquid phase will be assumed to be independent of the concentration of dissolved air and the gas phase will be assumed to be a mixture of dry air and
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.
Fleury, Leesa M
2016-01-01
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.
Slug modeling with 1D two-fluid model
International Nuclear Information System (INIS)
Simulations of condensation-induced water hammer with one-dimensional two-fluid model requires explicit modeling of slug formation, slug propagation, and in some cases slug decay. Stratified flow correlations that are more or less well known in 1D two-fluid models, are crucial for accurate description of the initial phase of the slug formation and slug propagation. Slug formation means transition to other flow regime that requires different set of correlations. To use such two-fluid model for condensation induced water hammer simulations, a single slug must be explicitly recognized and captured. In the present work two cases of condensation-induced water hammer simulations performed with WAHA code, are described and discussed: injection of cold liquid into horizontal pipe filled with steam and injection of hot steam into horizontal pipe partially filled with cold liquid. (author)
1D PIC simulation of relativistic Buneman instability
International Nuclear Information System (INIS)
Buneman instability in the relativistic regime has been studied using a 1D electrostatic particle-in-cell code. In the non-relativistic case, Hirose et al. (Plasma Phys. 20, 481(1978)) has shown that breakdown of linear growth (saturation) occurs when |E|2/16πW0 ∼ ζomax, where W0 is the initial beam kinetic energy density and ζomax is maximum growth rate of the instability. In the weakly relativistic case, it has been confirmed using PIC simulation that scaling of saturation of Buneman instability follows a similar behavior as the non-relativistic case, whereas in the strongly relativistic case our simulation results show significant deviation from Hirose's results. In the strongly relativistic case, growth rate reduces due to relativistic corrections; so saturation occurs at a lower value compared to the non-relativistic/weakly relativistic case. (author)
Assessment of the 2D/1D implementation in MPACT
International Nuclear Information System (INIS)
The 2D/1D method is used in the MPACT code to obtain 3D solutions of the Boltzmann transport equation for practical reactor geometries. The OECD C5G7 transport benchmark problem is used first to assess the accuracy of the method with a fixed set of cross-sections. The VERA Core Physics Progression Problems are then used to compare the accuracy of the transport solver using a 56-group library based on ENDFB-VII.0. Single assembly PWR designs are simulated, and the eigenvalue and pin powers are compared to continuous-energy Monte Carlo results. A 3x3 assembly cluster with a control rod inserted into the center assembly is then compared to Monte Carlo to assess the ability of MPACT to predict a control rod worth curve. Finally, MPACT is used to simulate the initial critical states of a full 3D initial core of a PWR at zero power conditions. (author)
1-D Molecular Chains of Thiophene on Ge(100)
Jeon, Seok Min; Jung, Soon Jung; Kim, Hyeong-Do; Lim, Do Kyung; Lee, Hangil; Kim, Sehun
2007-01-01
The adsorption geometry of thiophene on Ge(100) have been studied by high-resolution core-level photoemission spectroscopy (HRPES) using synchrotron radiation and scanning tunneling microscopy (STM). From the analysis of the Ge 3d, S 2p, and C 1s core-level photoemission spectra, we found three different adsorption geometries, which were assigned to a dative bonding feature, a [4+2] cycloaddition reaction product, and a desulfurization reaction product. Furthermore, we investigated that the ratio of the components induced by three adsorption geometries changed depending on the molecular coverage and the annealing temperature. At low coverage, the kinetically favorable dative bonding features favorably form 1-D molecular chains. Increasing the molecular coverage, the energetically more stable [4+2] cycloaddition reaction products are additionally created.
Microlens Masses from 1-D Parallaxes and Heliocentric Proper Motions
Gould, Andrew
2014-01-01
One-dimensional (1-D) microlens parallaxes can be combined with heliocentric lens-source relative proper motion measurements to derive the lens mass and distance, as suggested by Ghosh et al. (2004). Here I present the first mathematical anlysis of this procedure, which I show can be represented as a quadratic equation. Hence, it is formally subject to a two-fold degeneracy. I show that this degeneracy can be broken in many cases using the relatively crude 2-D parallax information that is often available for microlensing events. I also develop an explicit formula for the region of parameter space where it is more difficult to break this degeneracy. Although no mass/distance measurements have yet been made using this technique, it is likely to become quite common over the next decade.
A 1-D morphodynamic model of postglacial valley incision
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.
Accurate Insertion Loss Measurements of the Juno Patch Array Antennas
Chamberlain, Neil; Chen, Jacqueline; Hodges, Richard; Demas, John
2010-01-01
This paper describes two independent methods for estimating the insertion loss of patch array antennas that were developed for the Juno Microwave Radiometer instrument. One method is based principally on pattern measurements while the other method is based solely on network analyzer measurements. The methods are accurate to within 0.1 dB for the measured antennas and show good agreement (to within 0.1dB) of separate radiometric measurements.
3D/1D Analysis of ICRF Antennas
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
Feng, Gang; Freund, L. B.
2010-06-01
Cubic layered heterostructures are indispensable features of many electronic devices; however, the lattice mismatch tends to induce defects, e.g. dislocations. Glissile 60° misfit dislocations (MDs) generally form in the early stage of strain relaxation. During annealing, each relaxing 60° dislocation compensated-pair (60DCP) (with canceling screw and interface-perpendicular edge components) may coalesce into a 90° (pure edge) dislocation, which is a possible mechanism for the reduction of threading dislocations (TDs) through annealing. In this paper, we calculate the formation energies of periodic one-dimensional (1D) and two-dimensional (2D) arrays on the basis of linear elasticity. Each 1D 60DCP array always has lower energy than its homogeneous counterpart. The situation of each 2D array (containing two mutually orthogonal 1D arrays) depends on the period difference δ between the two individual 1D arrays and the film thickness. If δ=0, each 2D 60DCP array has higher energy than its homogeneous counterpart, whereas the 2D 60DCP array is energetically more favorable for a larger δ and/or a thicker film. The analysis suggests a semiconductor-processing strategy to obtain 90° dislocation-dominant arrays and to reduce TDs. Furthermore, based on the criterion of zero energy change by inserting the last dislocation to complete an array, we calculate the equilibrium array period for various configurations, implying possible strain over-relaxation (>100%-relaxed condition) for a sufficiently thick film.
Graphs on uniform points in [0,1]d
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 graph are described. Almost-sure asymptotic rates of convergence/divergence are obtained for various quantities, including the maximum and minimum vertex degree of the random graph, its clique number, chromatic number, and independence number, as the number n of points becomes large and the edge distance x is allowed to vary with n. The connectivity distance cn, the smallest x such that Gn(x) is connected, and the largest nearest neighbor link dn, the smallest x such that Gn(x) has no vertices of degree zero, are asymptotic in ratio, as n becomes large, for d >= 2.
1D dynamic beam modulation: methods to counteract inertia effects
International Nuclear Information System (INIS)
Dynamic modulation can be affected by inaccuracies when the required acceleration is larger than the highest allowed by the mechanical characteristics of the whole apparatus. In this study, inertia effects have been investigated with regard to the single absorber 1D modulation, analysing primarily how the acceleration performed by the modulating system affects the realization of 'single absorber' fluence profiles and the type of correction which could be devised. The observed percentage deviations from desired modulation at the lowest fluence coordinate of single minimum fluence profiles, when no correction is applied, were almost negligible for 'easy' modulations of the incident fluence (i.e. slow gradients); deviations became increasingly relevant as the moving absorber executed steeper gradients (a 17.6% higher dose being delivered in the minimum position when a 0.2 modulation is required). By applying the proposed corrections, the single absorber performances were improved to a satisfactory level, with a maximum deviation from desired modulation in the minima within 1.6%. (author)
Nonclassical Particle Transport in 1-D Random Periodic Media
Vasques, Richard; Slaybaugh, Rachel N
2016-01-01
We investigate the accuracy of the recently proposed nonclassical transport equation. This equation contains an extra independent variable compared to the classical transport equation (the path-length $s$), and models particle transport taking place in homogenized random media in which a particle's distance-to-collision is not exponentially distributed. To solve the nonclassical equation one needs to know the $s$-dependent ensemble-averaged total cross section, $\\Sigma_t(\\mu,s)$, or its corresponding path-length distribution function, $p(\\mu,s)$. We consider a 1-D spatially periodic system consisting of alternating solid and void layers, randomly placed in the $x$-axis. We obtain an analytical expression for $p(\\mu,s)$ and use this result to compute the corresponding $\\Sigma_t(\\mu,s)$. Then, we proceed to numerically solve the nonclassical equation for different test problems in rod geometry; that is, particles can move only in the directions $\\mu=\\pm 1$. To assess the accuracy of these solutions, we produce ...
The molecular spin filter constructed from 1D organic chain
International Nuclear Information System (INIS)
We proposed a molecular spin filter, which is constructed from the 1D metallic organic chain (Fen+1(C6H4)n). The spin-polarized transport properties of the molecular spin filter are explored by combining density functional theory with nonequilibrium Green's function formalism. Theoretical results reveal that Fen+1(C6H4)n molecular chain exhibits robust spin filtering effect, and only the spin-down electrons can transmit through the molecular chain. At the given bias voltage window [−1 eV,1 eV], the calculated spin filter efficiency is close to 100% in the case of n≥3. We find that the effect of spin polarization origin from both Fen+1 and (C6H4)n. In addition, negative difference resistance behavior appears in Fen+1(C6H4)n molecular chain. The results can help us understand the spin transport properties of organic molecular chain. - Highlights: • Theoretical results reveal that Fen+1(C6H4)n molecular chain exhibits robust spin filtering effect. • The effect of spin polarization origin from both of Fen+1 and (C6H4)n. • Negative difference resistance behavior appears in Fen+1(C6H4)n molecular chain
Havlickova, E; Subba, F; Coster, D; Wischmeier, M; Fishpool, G
2013-01-01
A 1D code modelling SOL transport parallel to the magnetic field (SOLF1D) is benchmarked with 2D simulations of MAST-U SOL performed via the SOLPS code for two different collisionalities. Based on this comparison, SOLF1D is then used to model the effects of divertor leg stretching in 1D, in support of the planned Super-X divertor on MAST. The aim is to separate magnetic flux expansion from volumetric power losses due to recycling neutrals by stretching the divertor leg either vertically or radially.
Havlickova, E.; Fundamenski, W.; Subba, F.; Coster, D; Wischmeier, M; Fishpool, G.
2013-01-01
A 1D code modelling SOL transport parallel to the magnetic field (SOLF1D) is benchmarked with 2D simulations of MAST-U SOL performed via the SOLPS code for two different collisionalities. Based on this comparison, SOLF1D is then used to model the effects of divertor leg stretching in 1D, in support of the planned Super-X divertor on MAST. The aim is to separate magnetic flux expansion from volumetric power losses due to recycling neutrals by stretching the divertor leg either vertically or ra...
Indian Academy of Sciences (India)
PRITAM PATIL; GANESH GAIKWAD; D R PATIL; JITENDRA NAIK
2016-06-01
1-D ZnO nanorods and PPy/1-D ZnO nanocomposites were prepared by the surfactant-assisted precipitation and in situ polymerization method, respectively. The synthesized nanorods and nanocomposites were characterized by UV–Vis spectrophotometer, Fourier transform-infrared spectroscopy (FTIR), X-ray diffraction (XRD) and field emission scanning electron microscope (FE-SEM), which gave the evidence of 1-D ZnO nanorods, polymerization of pyrrole monomer and strong interaction between PPy and 1-D ZnO nanorods, respectively. Photocatalytic activity of 1-D ZnO nanorods was conducted by $3^3$ level full-factorial design to evaluate the effect of three independent process variables viz., dye concentration (crystal violet), catalyst concentration (1-D ZnO nanorods) and the reaction time on the preferred response: photodegradation efficiency (%). The PPy/1-D ZnO nanocompositeswere used for the sensing of NH$_3$, LPG, CO$_2$ and H$_2$S gases, respectively, at room temperature. It was observed that PPy/1-D ZnO nanocomposites with different 1-D ZnO nanorod weight ratios (15 and 25%) had better selectivity and sensitivity towards NH3 at room temperature.
Variable-range hopping in 2D quasi-1D electronic systems
International Nuclear Information System (INIS)
A semi-phenomenological theory of variable-range hopping (VRH) is developed for two-dimensional (2D) quasi-one-dimensional (quasi-1D) systems such as arrays of quantum wires in the Wigner crystal regime. The theory follows the phenomenology of Efros, Mott and Shklovskii allied with microscopic arguments. We first derive the Coulomb gap in the single-particle density of states, g(ε), where ε is the energy of the charge excitation. We then derive the main exponential dependence of the electron conductivity in the linear (L), i.e. σ(T) ∼ exp [-(TL/T)γL], and current in the non-linear (NL), i.e. j(E) ∼ [-(ENL/E)γNL], response regimes (E is the applied electric field). Due to the strong anisotropy of the system and its peculiar dielectric properties we show that unusual, with respect to known results, Coulomb gaps open followed by unusual VRH laws, i.e. with respect to the disorder-dependence of TL and ENL and the values of γL and γNL. (author)
Evidence against dopamine D1/D2 receptor heteromers
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
A new general 1-D vadose zone flow solution method
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.
SWAN-PPL, Fusion Reactor 1-D Particle Transport Optimization
International Nuclear Information System (INIS)
1 - Description of problem or function: Given the material density profiles which describe a one-dimensional reference system with a neutron source, SWAN will calculate, and optionally implement, density changes so as to optimize a single functional parameter of the system. 2 - Method of solution: The one-dimensional discrete-ordinate transport code ANISN is used to calculate flux and adjoint distributions for specified sources. The code SWIF calculates first-order estimates of the effect of material density changes on a goal functional, and from these evaluates effectiveness functions for the substitution of one material for another. Density distribution changes are then calculated which would optimize the goal functional, optionally subject to a constraint of holding another functional constant (to first order). 3 - Restrictions on the complexity of the problem: SWAN is not designed to analyze critical systems; it assumes that there is a fixed source, as in shielding or fusion reactor applications. Otherwise it is compatible with ANISN. All arrays are variably-dimensioned, so that there are no restrictions on individual dimensions
Fast Optimal Load Balancing Algorithms for 1D Partitioning
Energy Technology Data Exchange (ETDEWEB)
Pinar, Ali; Aykanat, Cevdet
2002-12-09
One-dimensional decomposition of nonuniform workload arrays for optimal load balancing is investigated. The problem has been studied in the literature as ''chains-on-chains partitioning'' problem. Despite extensive research efforts, heuristics are still used in parallel computing community with the ''hope'' of good decompositions and the ''myth'' of exact algorithms being hard to implement and not runtime efficient. The main objective of this paper is to show that using exact algorithms instead of heuristics yields significant load balance improvements with negligible increase in preprocessing time. We provide detailed pseudocodes of our algorithms so that our results can be easily reproduced. We start with a review of literature on chains-on-chains partitioning problem. We propose improvements on these algorithms as well as efficient implementation tips. We also introduce novel algorithms, which are asymptotically and runtime efficient. We experimented with data sets from two different applications: Sparse matrix computations and Direct volume rendering. Experiments showed that the proposed algorithms are 100 times faster than a single sparse-matrix vector multiplication for 64-way decompositions on average. Experiments also verify that load balance can be significantly improved by using exact algorithms instead of heuristics. These two findings show that exact algorithms with efficient implementations discussed in this paper can effectively replace heuristics.
PPM1D exerts its oncogenic properties in human pancreatic cancer through multiple mechanisms.
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
DEFF Research Database (Denmark)
Treebak, Jonas Thue; Pehmøller, Christian; Kristensen, Jonas Møller;
2014-01-01
We investigated the phosphorylation signatures of two Rab GTPase activating proteins TBC1D1 and TBC1D4 in human skeletal muscle in response to physical exercise and physiological insulin levels induced by a carbohydrate rich meal using a paired experimental design. Eight healthy male volunteers...... TBC1D4 in response to physiological stimuli in human skeletal muscle and support the idea that Akt and AMPK are upstream kinases. TBC1D1 phosphorylation signatures were comparable between in vitro contracted mouse skeletal muscle and exercised human muscle, and we show that AMPK was regulating...... phosphorylation of these sites in mouse muscle. Contraction and exercise elicited a different phosphorylation pattern of TBC1D4 in mouse compared with human muscle, and although different circumstances in our experimental setup may contribute to this difference, the observation exemplifies that transferring...
Energy Technology Data Exchange (ETDEWEB)
Yashchuk, Valeriy V.; McKinney, Wayne R.; Takacs, Peter Z.
2008-05-19
We suggest and describe the use of a binary pseudo-random grating as a standard test surface for calibration of the modulation transfer function of microscopes. Results from calibration of a MicromapTM-570 interferometric microscope are presented.
TBC1D1 Regulates Insulin- and Contraction-Induced Glucose Transport in Mouse Skeletal Muscle
Toyoda, Taro; Yu, Haiyan; Fujii, Nobuharu; Hirshman, Michael F.; An, Ding Jeff; Goodyear, Laurie Joy; Taylor, Eric B.
2010-01-01
OBJECTIVE: TBC1D1 is a member of the TBC1 Rab-GTPase family of proteins and is highly expressed in skeletal muscle. Insulin and contraction increase TBC1D1 phosphorylation on phospho-Akt substrate motifs (PASs), but the function of TBC1D1 in muscle is not known. Genetic linkage analyses show a TBC1D1 R125W missense variant confers risk for severe obesity in humans. The objective of this study was to determine whether TBC1D1 regulates glucose transport in skeletal muscle. RESEARCH DESIGN AND M...
Grid Cell Responses in 1D Environments Assessed as Slices through a 2D Lattice.
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
Endogenous N-terminal Domain Cleavage Modulates α1D-Adrenergic Receptor Pharmacodynamics.
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
1D non-uniform dose delivery by a single dynamic absorber
International Nuclear Information System (INIS)
A new technique for 1D non-uniform dose delivery has been recently proposed, using a single computer-controlled dynamic absorber, which is driven within the beam during irradiation. Analytical-iterative and convolution algorithms have been developed in order to optimize the movement of the absorber in creating wished beam modulations. The technique has been demonstrated to be suitable for many applications in the fields of dynamic wedging, tissue-deficit compensation and, in some cases, conformal therapy by non-uniform dose delivery. A first non-focused prototype has been shown to be able to reproduce a number of modulated beams with an acceptable accuracy (Phys.Med. Biol. 40: 221-240, 1995). A new focused prototype has been carried out at our Institute and it is under investigation: preliminary tests (by diodes array and film dosimetry) confirm the wide possibilities of clinical application. The apparatus, which can be inserted in the tray holder of our Clinac Varian 6/100, is connected through a mechanical transmission system to a computer where absorber's speed profiles (corresponding to wished fluence profiles) are stored. The operator can recall the wished profile and move the absorber in the due way, when the irradiation starts. The single-absorber dynamic modulation technique cannot modulate the beam fluence in any way one wishes, due to the physical constraint that the absorber can stay in the irradiation field for a time not larger than the total irradiation time: however it can create a large number of dynamically modulated beams clinically interesting. For this reason it should be considered as a valid 'low-cost' technique for dynamic beam modulation (also on Linacs which do not have complex computer-controlled options for non-uniform dose delivery such as dynamic collimators and multi leaves)
Off-chip beam steering with a one-dimensional optical phased array on silicon-on-insulator
Van Acoleyen, Karel; Bogaerts, Wim; Jágerská, Jana; Le Thomas, Nicolas; Houdré, Romuald; Baets, Roel
2009-01-01
Optical phased arrays are versatile components enabling rapid and precise beam steering. An integrated approach is followed in which a 1D optical phased array is fabricated on silicon-on-insulator. The optical phased array consists of 16 parallel grating couplers spaced 2 mu m apart. Steering in one direction is done thermo-optically by means of a titanium electrode on top of the structure using the phased array principle, while steering in the other direction is accomplished by wavelength tu...
关于图的L(d1,d2)-标号问题%The L(d1, d2)-Labeling Problem on Graphs
Institute of Scientific and Technical Information of China (English)
邵振东; 刘家壮
2006-01-01
The L(2, 1)-labeling is formulated from the frequency assignment problem. We study the L(d1, d2)- labeling which is a generalization of the L(2, 1)-labeling. Vertex 2-coloring, 2-chromatic number and other related concepts are firstly defined, and the upper bound for 2-chromatic number is given; a very general relationship between λd1 ,d2 (G) and minimum degree δ(G) and maximum degree △(G) is then derived; finally, the upper bounds of L(d1, d2)-labelings of general and planar graphs are given.%图的L(2,1)-标号问题是由频率分配问题归结而来,本文研究作为L(2,1)-标号问题的推广的L(d1,d2)-标号问题.首先定义了顶点2-着色,2-色数及其它有关概念,给出了2-色数的上界.然后得出了λd1,d2(G)与δ(G)和△(G)的一般关系.最后得出了一般图与平面图的λd1,d2(G)的上界.
A Proposal for Realizing an Array of Bose-Einstein Condensates
Institute of Scientific and Technical Information of China (English)
印建平; 高伟建; 胡建军
2002-01-01
We propose one-dimensional (1D) and two-dimensional (2D) arrays of magnetic surface microtraps for coldalkali atoms using some arrays of current-carrying wires and we calculate the spatial distributions of magneticfields from the 1D and 2D arrays of current-carrying wires. The field gradients and curvatures from a singlemagnetic microtrap are analysed, and some interesting and periodic magnetic-well microstructures are found.The result shows that a magnetic-field gradient greater than 2.4 × 105 G/cm and a field curvature greater than4.05 × 108 G/cm2 can be generated in our array of magnetic microtraps, which can be used to realize the 1Dand 2D arrays of Bose-Einstein condensations (or 1D and 2D arrays of Bose clusters) by rf-induced evaporativecooling, and then to form 1D and 2D atomic magnetic lattices, even to prepare 1D and 2D photonic crystals.
Exercise increases TBC1D1 phosphorylation in human skeletal muscle
Jessen, Niels; An, Ding; Lihn, Aina S.; Nygren, Jonas; Hirshman, Michael F.; Thorell, Anders; Goodyear, Laurie J.
2011-01-01
Exercise and weight loss are cornerstones in the treatment and prevention of type 2 diabetes, and both interventions function to increase insulin sensitivity and glucose uptake into skeletal muscle. Studies in rodents demonstrate that the underlying mechanism for glucose uptake in muscle involves site-specific phosphorylation of the Rab-GTPase-activating proteins AS160 (TBC1D4) and TBC1D1. Multiple kinases, including Akt and AMPK, phosphorylate TBC1D1 and AS160 on distinct residues, regulatin...
1D engine simulation of a turbocharged SI engine with CFD computation on components
Renberg, Ulrica
2008-01-01
Techniques that can increase the SI- engine efficiency while keeping the emissions very low is to reduce the engine displacement volume combined with a charging system. Advanced systems are needed for an effective boosting of the engine and today 1D engine simulation tools are often used for their optimization. This thesis concerns 1D engine simulation of a turbocharged SI engine and the introduction of CFD computations on components as a way to assess inaccuracies in the 1D model. 1D engine ...
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
Energy Technology Data Exchange (ETDEWEB)
Ozaki, N.; Lappalainen, J.; Linnoila, M. [National Institute on Alcohol Abuse and Alcoholism, Rockville, MD (United States)] [and others
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.
Mandre, Shreyas
2016-01-01
Wind and hydrokinetic turbine array performance suffers because the wakes of upstream turbines diminish flow to downstream turbines. Here we analyze systematic deflection of the wakes to direct unimpeded flow onto the downstream turbines and increase the area power density. We examine the case of an abstract 1D turbine-deflector array aligned parallel to a 2D free stream flow, in which case the array presents negligible frontal area to the flow without deflection. Using the framework of inviscid fluid dynamics, the flow manipulation is decomposed into flow deflection due to bound vorticity in the array, and energy extraction resulting from free vorticity shed by the array. While this general framework is agnostic to the technological details, it captures the geometry of a vertical fence of turbines and deflectors along the centerline of a river, minimizing the array footprint. We find a localized array can direct significant kinetic energy through itself, while having a minimal impact on array efficiency; the...
Identification of RAPD Marker for Chromosome 1D of Common Wheat
Directory of Open Access Journals (Sweden)
Imtiaz Ahmad Khan
2010-04-01
Full Text Available Development of genetically compensating nullisomic-tetrasomic and ditelosomic lines of commonwheat (Triticum aestivum L. have been widely used to construct high density genetic maps of homoeologouswheat chromosomes. During present research, easier, cheaper and quicker procedure of Polymerase ChainReaction (PCR was used to map Randomly Amplified Polymorphic DNA primers on chromosome 1D ofcommon wheat. Genomic DNA was isolated from two genetic stocks of wheat cultivar Chinese Spring viz;NT-1D1B and NT-2A2B. PCR were conducted using RAPD primers GLC-07 and GLC-11. RAPD primerGLC-11 amplified a polymorphic allele of approximately 500 bp, which was present in NT-2A2B (used aspositive control but was absent in NT-1D1B indicating that the locus is present on chromosome 1D of commonwheat. Hence this marker (GLC-11 can reliably be used to keep track of chromosome 1D of hexaploid wheat.
International Nuclear Information System (INIS)
A fully relativistic Dirac-Fock method with Breit and QED corrections has been employed to study energy levels and oscillator strengths for the ns(n-1)d 1D-ns21S transitions of the alkaline earth atoms. In calculation, the authors consider significant Breit and QED corrections, the results are in good agreements with recent experimental data and other theoretical values. The results show that it is feasible to obtain the highly Rybderg states of the alkaline earth atoms, especially the autoionization states, by use of quadrupole transitions as an intermediate resonance
Energy Technology Data Exchange (ETDEWEB)
Wee, W H; Pendry, J B [Condensed Matter Theory Group Department of Physics Imperial College London London SW7 2AZ (United Kingdom)], E-mail: w.wee07@imperial.ac.uk
2010-03-15
For a long time phase arrays have been used in a variety of wave transmission applications because of their simplicity and versatility. Conventionally there is a trade-off between the compactness of a phase array and its directivity. In this paper we demonstrate how by embedding a normal phase array within a superlens (made of negative refractive index material) we can overcome this constraint and create compact phase arrays with a virtual extent much larger than the physical size of the array. In this paper we also briefly discuss the apparent unphysical field divergences in superlenses and how to resolve this issue.
International Nuclear Information System (INIS)
For a long time phase arrays have been used in a variety of wave transmission applications because of their simplicity and versatility. Conventionally there is a trade-off between the compactness of a phase array and its directivity. In this paper we demonstrate how by embedding a normal phase array within a superlens (made of negative refractive index material) we can overcome this constraint and create compact phase arrays with a virtual extent much larger than the physical size of the array. In this paper we also briefly discuss the apparent unphysical field divergences in superlenses and how to resolve this issue.
Use of optimized 1D TOCSY NMR for improved quantitation and metabolomic analysis of biofluids
Energy Technology Data Exchange (ETDEWEB)
Sandusky, Peter [Eckerd College, Department of Chemistry (United States); Appiah-Amponsah, Emmanuel; Raftery, Daniel, E-mail: raftery@purdue.edu [Purdue University, Department of Chemistry (United States)
2011-04-15
One dimensional selective TOCSY experiments have been shown to be advantageous in providing improved data inputs for principle component analysis (PCA) (Sandusky and Raftery 2005a, b). Better subpopulation cluster resolution in the observed scores plots results from the ability to isolate metabolite signals of interest via the TOCSY based filtering approach. This report reexamines the quantitative aspects of this approach, first by optimizing the 1D TOCSY experiment as it relates to the measurement of biofluid constituent concentrations, and second by comparing the integration of 1D TOCSY read peaks to the bucket integration of 1D proton NMR spectra in terms of precision and accuracy. This comparison indicates that, because of the extensive peak overlap that occurs in the 1D proton NMR spectra of biofluid samples, bucket integrals are often far less accurate as measures of individual constituent concentrations than 1D TOCSY read peaks. Even spectral fitting approaches have proven difficult in the analysis of significantly overlapped spectral regions. Measurements of endogenous taurine made over a sample population of human urine demonstrates that, due to background signals from other constituents, bucket integrals of 1D proton spectra routinely overestimate the taurine concentrations and distort its variation over the sample population. As a result, PCA calculations performed using data matrices incorporating 1D TOCSY determined taurine concentrations produce better scores plot subpopulation cluster resolution.
rasdaman Array Database: current status
Merticariu, George; Toader, Alexandru
2015-04-01
rasdaman (Raster Data Manager) is a Free Open Source Array Database Management System which provides functionality for storing and processing massive amounts of raster data in the form of multidimensional arrays. The user can access, process and delete the data using SQL. The key features of rasdaman are: flexibility (datasets of any dimensionality can be processed with the help of SQL queries), scalability (rasdaman's distributed architecture enables it to seamlessly run on cloud infrastructures while offering an increase in performance with the increase of computation resources), performance (real-time access, processing, mixing and filtering of arrays of any dimensionality) and reliability (legacy communication protocol replaced with a new one based on cutting edge technology - Google Protocol Buffers and ZeroMQ). Among the data with which the system works, we can count 1D time series, 2D remote sensing imagery, 3D image time series, 3D geophysical data, and 4D atmospheric and climate data. Most of these representations cannot be stored only in the form of raw arrays, as the location information of the contents is also important for having a correct geoposition on Earth. This is defined by ISO 19123 as coverage data. rasdaman provides coverage data support through the Petascope service. Extensions were added on top of rasdaman in order to provide support for the Geoscience community. The following OGC standards are currently supported: Web Map Service (WMS), Web Coverage Service (WCS), and Web Coverage Processing Service (WCPS). The Web Map Service is an extension which provides zoom and pan navigation over images provided by a map server. Starting with version 9.1, rasdaman supports WMS version 1.3. The Web Coverage Service provides capabilities for downloading multi-dimensional coverage data. Support is also provided for several extensions of this service: Subsetting Extension, Scaling Extension, and, starting with version 9.1, Transaction Extension, which
Charge Transport in 1-D Nanostructured CdS Dye Sensitized Solar Cell
International Nuclear Information System (INIS)
Charge transport in eosin yellow sensitized CdS 1-D nanostructures is studied. Direct conduction pathway for electron transport in nanowires enhances Voc in CdS nanowires compared to nanorods and nanoparticles. J-V characterization of nanowires results in improved efficiency of 0.184% due to fewer interparticle connections. Increase in Jsc is observed by coating CdS 1-D nanostructures on TiO2 substrate which reduces rate of recombination and photocorrosive nature of CdS photoanodes. Enhancement in efficiency up to 0.501% is achieved for CdS 1-D nanostructures DSSCs on TiO2 substrate.
Non-uniform black strings and the critical dimension in the $1/D$ expansion
Suzuki, Ryotaku; Tanabe, Kentaro
2015-01-01
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 $...
Development of a 1D neutron transport code employing the method of characteristics
International Nuclear Information System (INIS)
To investigate the 2D/1D fusion core analysis method, a 1D neutron transport problem solver, PEACH-ID, is developed. It is a code of method of characteristics (MOC), both the usual fiat-source step characteristics (SC) scheme and linear source (LS) approximation scheme are adopted for tracking calculation along the neutron flying trajectory. Exponential function interpolation table and fission source extrapolation are adopted as two major methods to accelerate the computational process. Numerical results demonstrate that PEACH-1D is accurate and efficient, and the proposed LS scheme is able to handle quite larger mesh division and deserves much more application in the MOC codes. (authors)
CD1d and invariant NKT cells at the human maternal–fetal interface
Boyson, Jonathan E.; Rybalov, Basya; Koopman, Louise A.; Exley, Mark; Balk, Steven P.; Racke, Frederick K.; Schatz, Frederick; Masch, Rachel; Wilson, S. Brian; Strominger, Jack L.
2002-01-01
Invariant CD1d-restricted natural killer T (iNKT) cells comprise a small, but significant, immunoregulatory T cell subset. Here, the presence of these cells and their CD1d ligand at the human maternal–fetal interface was investigated. Immunohistochemical staining of human decidua revealed the expression of CD1d on both villous and extravillous trophoblasts, the fetal cells that invade the maternal decidua. Decidual iNKT cells comprised 0.48% of the decidual CD3+ T cell population, a frequency...
Energy Technology Data Exchange (ETDEWEB)
Kong, Chen; Lange, Jeffrey J.; Samovski, Dmitri [Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63110 (United States); Su, Xiong [Department of Internal Medicine, Center for Human Nutrition Washington University School of Medicine, St. Louis, MO 63110 (United States); Liu, Jialiu [Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63110 (United States); Sundaresan, Sinju [Department of Internal Medicine, Center for Human Nutrition Washington University School of Medicine, St. Louis, MO 63110 (United States); Stahl, Philip D., E-mail: pstahl@wustl.edu [Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63110 (United States)
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.
Optical analogue of relativistic Dirac solitons in binary waveguide arrays
International Nuclear Information System (INIS)
We study analytically and numerically an optical analogue of Dirac solitons in binary waveguide arrays in the presence of Kerr nonlinearity. Pseudo-relativistic soliton solutions of the coupled-mode equations describing dynamics in the array are analytically derived. We demonstrate that with the found soliton solutions, the coupled mode equations can be converted into the nonlinear relativistic 1D Dirac equation. This paves the way for using binary waveguide arrays as a classical simulator of quantum nonlinear effects arising from the Dirac equation, something that is thought to be impossible to achieve in conventional (i.e. linear) quantum field theory. -- Highlights: •An optical analogue of Dirac solitons in nonlinear binary waveguide arrays is suggested. •Analytical solutions to pseudo-relativistic solitons are presented. •A correspondence of optical coupled-mode equations with the nonlinear relativistic Dirac equation is established
Carbon nanotube nanoelectrode arrays
Ren, Zhifeng; Lin, Yuehe; Yantasee, Wassana; Liu, Guodong; Lu, Fang; Tu, Yi
2008-11-18
The present invention relates to microelectode arrays (MEAs), and more particularly to carbon nanotube nanoelectrode arrays (CNT-NEAs) for chemical and biological sensing, and methods of use. A nanoelectrode array includes a carbon nanotube material comprising an array of substantially linear carbon nanotubes each having a proximal end and a distal end, the proximal end of the carbon nanotubes are attached to a catalyst substrate material so as to form the array with a pre-determined site density, wherein the carbon nanotubes are aligned with respect to one another within the array; an electrically insulating layer on the surface of the carbon nanotube material, whereby the distal end of the carbon nanotubes extend beyond the electrically insulating layer; a second adhesive electrically insulating layer on the surface of the electrically insulating layer, whereby the distal end of the carbon nanotubes extend beyond the second adhesive electrically insulating layer; and a metal wire attached to the catalyst substrate material.
Non-uniform black strings and the critical dimension in the $1/D$ expansion
Suzuki, Ryotaku
2015-01-01
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 $D_*\\simeq13.5$ 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.
Non-uniform black strings and the critical dimension in the 1/D expansion
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.
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
1D model for the dynamics and expansion of elongated Bose-Einstein condensates
Massignan, Pietro; Modugno, Michele
2002-01-01
We present a 1D effective model for the evolution of a cigar-shaped Bose-Einstein condensate in time dependent potentials whose radial component is harmonic. We apply this model to investigate the dynamics and expansion of condensates in 1D optical lattices, by comparing our predictions with recent experimental data and theoretical results. We also discuss negative-mass effects which could be probed during the expansion of a condensate moving in an optical lattice.
Kayserili Karabey, Hülya; Schmidts, Miriam; Hou, Yuqing; Cortes, 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; 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. W...
Optimization of a cyclic peptide inhibitor of Ser/Thr phosphatase PPM1D (Wip1).
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
Momentum Conservation Implies Anomalous Energy Transport in 1D Classical Lattices
International Nuclear Information System (INIS)
Under quite general conditions, we prove that for classical many-body lattice Hamiltonians in one dimension (1D) total momentum conservation implies anomalous conductivity in the sense of the divergence of the Kubo expression for the coefficient of thermal conductivity, κ . Our results provide rigorous confirmation and explanation of many of the existing ''surprising'' numerical studies of anomalous conductivity in 1D classical lattices, including the celebrated Fermi-Pasta-Ulam problem. (c) 2000 The American Physical Society
Momentum conservation implies anomalous energy transport in 1d classical lattices
Prosen, T; Prosen, Tomaz; Campbell, David K.
2000-01-01
Under quite general conditions, we prove that for classical many-body lattice Hamiltonians in one dimension (1D) total momentum conservation implies anomalous conductivity in the sense of the divergence of the Kubo expression for the coefficient of thermal conductivity, $\\kappa$. Our results provide rigorous confirmation and explanation of many of the existing ``surprising'' numerical studies of anomalous conductivity in 1D classical lattices, including the celebrated Fermi-Pasta-Ulam problem.
User's manual of the REFLA-1D/MODE4 reflood thermo-hydrodynamic analysis code
International Nuclear Information System (INIS)
REFLA-1D/MODE4 code has been developed by incorporating local power effect model and fuel temperature profile effect model into REFLA-1D/MODE3 code. This code can calculate the temperature transient of local rod by considering radial power profile effect in core and simulate the thermal characteristics of the nuclear fuel rod. This manual describes the outline of incorporated models, modification of the code with incorporating models and provides application information required to utilize the code. (author)
*609850 TBC1 DOMAIN FAMILY, MEMBER 1; TBC1D1 [OMIM
Lifescience Database Archive (English)
Full Text Available FIELD NO 609850 FIELD TI 609850 TBC1 DOMAIN FAMILY, MEMBER 1; TBC1D1 ;;KIAA1108 FIELD TX DESCRIP ... o obesity, see BMIQ7 (608410). ANIMAL MODEL In the lean ... Swiss Jim Lambert (SJL) strain of obesity-resistan ... .; Joost, H.-G.; Al-Hasani, H.: Tbc1d1 mutation in lean ... mouse strain confers lean ness and protects from di ...
Protective mucosal immunity mediated by epithelial CD1d and IL-10.
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
Protective mucosal immunity mediated by epithelial CD1d and IL-10
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
2014-01-01
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 host1,2. 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 disease3–8. As CD1d crosslinking on ...
Simple model of the density of states in 1D photonic crystal
Rudziński, Adam; Tyszka-Zawadzka, Anna; Szczepański, Paweł
2010-01-01
In this paper, we present a simple, yet versatile, analytical model of one-dimensional photonic crystal (1D PC). In our theoretical model, we take into account direction of propagation and therefore do not neglect anisotropic nature of photonic crystals. We derive analytical expressions for mode spectrum and density of states in 1D photonic crystal. With those formulas, we obtain mode spectrum characteristics, which depict formation of photonic band gap and reveal properties of photonic cryst...
Arrays of microscopic magnetic traps for cold atoms and their applications in atom optics
Institute of Scientific and Technical Information of China (English)
印建平; 高伟建; 胡建军
2002-01-01
A single microscopic magnetic trap for neutral atoms using planar current-carrying wires was proposed and studiedtheoretically by Weinstein et al. In this paper, we propose three structures of composite current-carrying wires to provide1D, 2D and 3D arrays of microscopic magnetic traps for cold alkali atoms. The spatial distributions of magnetic fieldsgenerated by these structures are calculated and the field gradient and curvature in each single microtrap are analysed.Our study shows that arrays of microscopic magnetic traps can be used to provide 1D, 2D or 3D atomic magneticlattices, and even to realize 1D, 2D and 3D arrays of magneto-optical traps, and so on.
Dynamics of reactions O((1)D)+C(6)H(6) and C(6)D(6).
Chen, Hui-Fen; Liang, Chi-Wei; Lin, Jim J; Lee, Yuan-Pern; Ogilvie, J F; Xu, Z F; Lin, M C
2008-11-01
The reaction between O((1)D) and C(6)H(6) (or C(6)D(6)) was investigated with crossed-molecular-beam reactive scattering and time-resolved Fourier-transform infrared spectroscopy. From the crossed-molecular-beam experiments, four product channels were identified. The major channel is the formation of three fragments CO+C(5)H(5)+H; the channels for formation of C(5)H(6)+CO and C(6)H(5)O+H from O((1)D)+C(6)H(6) and OD+C(6)D(5) from O((1)D)+C(6)D(6) are minor. The angular distributions for the formation of CO and H indicate a mechanism involving a long-lived collision complex. Rotationally resolved infrared emission spectra of CO (1ratio of [CO]/[OH]=2.1+/-0.4 for O((1)D)+C(6)H(6) and [CO]/[OD]>2.9 for O((1)D)+C(6)D(6) is consistent with the expectation for an abstraction reaction. The mechanism of the reaction may be understood from considering the energetics of the intermediate species and transition states calculated at the G2M(CC5) level of theory for the O((1)D)+C(6)H(6) reaction. The experimentally observed branching ratios and deuterium isotope effect are consistent with those predicted from calculations. PMID:19045343
Microplasma array serving as photonic crystals and plasmon chains
International Nuclear Information System (INIS)
An array of microplasmas with sizes ranging from a millimeter to a micrometer, has potential for novel and promising electromagnetic-wave media, especially when the wave frequency is below the electron plasma frequency. Photonic crystals or band-gap materials composed of microplasmas have unique properties arising from their loss term, and they can become band-pass filters instead of the band-stop filters usually observed in photonic crystals of dielectrics. Such behavior is well understood using the dispersion relation in a three-dimensional space of frequency and complex wavenumber with real and imaginary parts. Another functional array is a simple one-dimensional (1D) array; it can conduct microwaves for a wide frequency range below the electron plasma frequency. The propagating modes are similar to the coupling of localized surface plasmon polaritons observed along a metallic nanoparticle chain in the photon range; however a 1D microplasma array features differ from those of a metallic sphere array, leading to a dynamic wide-band waveguide. (author)
Shot noise in frustrated single-electron arrays
Kaplan, Daniel M.; Sverdlov, Victor A.; Likharev, Konstantin K.
2003-01-01
We have carried out numerical simulations of shot noise in 2D arrays of single-electron islands with random background charges. The results show that in contrast with the 1D arrays, at low currents the current noise is strongly colored, and its spectral density levels off at very low frequencies. The Fano factor may be much larger than unity, due to the remnants of single-electron/hole avalanches. However, even very small thermal fluctuations reduce the Fano factor below 1 for almost any bias.
Riedl, C; Akopov, Z; Amarian, M; Ammosov, V V; Andrus, A; Aschenauer, E C; Augustyniak, W; Avakian, R; Avetisian, A; Avetissian, E; Bailey, P; Baturin, V; Baumgarten, C; Beckmann, M; Belostotskii, S; Bernreuther, S; Bianchi, N; Blok, H P; Böttcher, Helmut B; Borisov, A; Bouwhuis, M; Brack, J; Brüll, A; Bryzgalov, V V; Capitani, G P; Chiang, H C; Ciullo, G; Contalbrigo, M; Dalpiaz, P F; De Leo, R; De Nardo, L; De Sanctis, E; Devitsin, E G; Di Nezza, P; Düren, M; Ehrenfried, M; Elalaoui-Moulay, A; Elbakian, G M; Ellinghaus, F; Elschenbroich, U; Ely, J; Fabbri, R; Fantoni, A; Feshchenko, A; Felawka, L; Fox, B; Franz, J; Frullani, S; Gärber, Y; Gapienko, G; Gapienko, V; Garibaldi, F; Garrow, K; Garutti, E; Gaskell, D; Gavrilov, G E; Karibian, V; Graw, G; Grebenyuk, O; Greeniaus, L G; Hafidi, K; Hartig, M; Hasch, D; Heesbeen, D; Henoch, M; Hertenberger, R; Hesselink, W H A; Hillenbrand, A; Hoek, M; Holler, Y; Hommez, B; Iarygin, G; Ivanilov, A; Izotov, A; Jackson, H E; Jgoun, A; Kaiser, R; Kinney, E; Kiselev, A; Königsmann, K C; Kopytin, M; Korotkov, V A; Kozlov, V; Krauss, B; Krivokhizhin, V G; Lagamba, L; Lapikas, L; Laziev, A; Lenisa, P; Liebing, P; Lindemann, T; Lipka, K; Lorenzon, W; Lü, J; Maiheu, B; Makins, N C R; Marianski, B; Marukyan, H O; Masoli, F; Mexner, V; Meyners, N; Miklukho, O; Miller, C A; Miyachi, Y; Muccifora, V; Nagaitsev, A; Nappi, E; Naryshkin, Yu; Nass, A; Negodaev, M A; Nowak, Wolf-Dieter; Oganessyan, K; Ohsuga, H; Orlandi, G; Pickert, N; Potashov, S Yu; Potterveld, D H; Raithel, M; Reggiani, D; Reimer, P E; Reischl, A; Reolon, A R; Rith, K; Airapetian, A; Rosner, G; Rostomyan, A; Rubacek, L; Ryckbosch, D; Salomatin, Yu I; Sanjiev, I; Savin, I; Scarlett, C; Schäfer, A; Schill, C; Schnell, G; Schüler, K P; Schwind, A; Seele, J; Seidl, R; Seitz, B; Shanidze, R G; Shearer, C; Shibata, T A; Shutov, V B; Simani, M C; Sinram, K; Stancari, M D; Statera, M; Steffens, E; Steijger, J J M; Stewart, J; Stösslein, U; Tait, P; Tanaka, H; Taroian, S P; Tchuiko, B; Terkulov, A R; Tkabladze, A V; Trzcinski, A; Tytgat, M; Vandenbroucke, A; Van der Nat, P B; van der Steenhoven, G; Vetterli, Martin C; Vikhrov, V; Vincter, M G; Visser, J; Vogel, C; Vogt, M; Volmer, J; Weiskopf, C; Wendland, J; Wilbert, J; Ybeles-Smit, G V; Yen, S; Zihlmann, B; Zohrabyan, H G; Zupranski, P; Riedl, Caroline
2005-01-01
Final HERMES results on the proton, deuteron and neutron structure function g1 are presented in the kinematic range 0.0021
Bi, Zhen; BenTov, Yoni; Xu, Cenke
2016-01-01
Motivated by recent studies of symmetry protected topological (SPT) phases, we explore the possible gapless quantum disordered phases in the $(2+1)d$ nonlinear sigma model defined on the Grassmannian manifold $\\frac{U(N)}{U(n)\\times U(N - n)}$ with a Wess-Zumino-Witten (WZW) term at level $k$, which is the effective low energy field theory of the boundary of certain $(3+1)d$ SPT states. With $k = 0$, this model has a well-controlled large-$N$ limit, $i.e.$ its renormalization group equations can be computed exactly with large-$N$. However, with the WZW term, the large-$N$ and large-$k$ limit alone is not sufficient for a reliable study of the nature of the quantum disordered phase. We demonstrate that at least for $n = 1$, through a combined large-$N$, large-$k$ and $3-\\epsilon$ generalization, a stable fixed point in the quantum disordered phase can be reliably located, which corresponds to a $(2+1)d$ strongly interacting conformal field theory. Extension of our method to $n > 1$ will also be discussed.
Energy Technology Data Exchange (ETDEWEB)
Andersen, Gary L.; DeSantis, Todd D.
2014-07-08
The present embodiments relate to an array system for detecting and identifying biomolecules and organisms. More specifically, the present embodiments relate to an array system comprising a microarray configured to simultaneously detect a plurality of organisms in a sample at a high confidence level.
Benchmarks and models for 1-D radiation transport in stochastic participating media
Energy Technology Data Exchange (ETDEWEB)
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.
Energy Technology Data Exchange (ETDEWEB)
Okandan, Murat (Edgewood, NM); Wessendorf, Kurt O. (Albuquerque, NM)
2007-12-11
An electrode array is disclosed which has applications for neural stimulation and sensing. The electrode array, in certain embodiments, can include a plurality of electrodes each of which is flexibly attached to a common substrate using a plurality of springs to allow the electrodes to move independently. In other embodiments of the electrode array, the electrodes can be fixed to the substrate. The electrode array can be formed from a combination of bulk and surface micromachining, and can include electrode tips having an electroplated metal (e.g. platinum, iridium, gold or titanium) or a metal oxide (e.g. iridium oxide) for biocompatibility. The electrode array can be used to form a part of a neural prosthesis, and is particularly well adapted for use in an implantable retinal prosthesis.
Botez, Dan; Scifres, Don R.
1994-08-01
This book provides a comprehensive overview of the fundamental principles and applications of semiconductor diode laser arrays. All of the major types of arrays are discussed in detail, including coherent, incoherent, edge- and surface-emitting, horizontal- and vertical-cavity, individually addressed, lattice- matched and strained-layer systems. The initial chapters cover such topics as lasers, amplifiers, external-cavity control, theoretical modeling, and operational dynamics. Spatially incoherent arrays are then described in detail, and the uses of vertical-cavity surface emitter and edge-emitting arrays in parallel optical-signal processing and multi-channel optical recording are discussed. Researchers and graduate students in solid state physics and electrical engineering studying the properties and applications of such arrays will find this book invaluable.
Microfabricated ion trap array
Blain, Matthew G.; Fleming, James G.
2006-12-26
A microfabricated ion trap array, comprising a plurality of ion traps having an inner radius of order one micron, can be fabricated using surface micromachining techniques and materials known to the integrated circuits manufacturing and microelectromechanical systems industries. Micromachining methods enable batch fabrication, reduced manufacturing costs, dimensional and positional precision, and monolithic integration of massive arrays of ion traps with microscale ion generation and detection devices. Massive arraying enables the microscale ion traps to retain the resolution, sensitivity, and mass range advantages necessary for high chemical selectivity. The reduced electrode voltage enables integration of the microfabricated ion trap array with on-chip circuit-based rf operation and detection electronics (i.e., cell phone electronics). Therefore, the full performance advantages of the microfabricated ion trap array can be realized in truly field portable, handheld microanalysis systems.
A Mathematical Model of T1D Acceleration and Delay by Viral Infection.
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
Deconvolution of Complex 1D NMR Spectra Using Objective Model Selection.
Directory of Open Access Journals (Sweden)
Travis S Hughes
Full Text Available 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/.
Possible Dimensional Crossover to 1D of ^3He Fluid in Nanochannels Observed in Susceptibilities
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.
REAL-TIME FLOOD FORECASTING METHOD WITH 1-D UNSTEADY FLOW MODEL
Institute of Scientific and Technical Information of China (English)
MU Jin-bin; ZHANG Xiao-feng
2007-01-01
A real-time forecasting method coupled with the 1-D unsteady flow model with the recursive least-square method was developed. The 1-D unsteady flow model was modified by using the time-variant parameter and revising it dynamically through introducing a variable weighted forgetting factor, such that the output of the model could be adjusted for the real time forecasting of floods. The application of the new real time forecasting model in the reach from Yichang to Luoshan of the Yangtze River was demonstrated. Computational result shows that the forecasting accuracy of the new model is much higher than that of the original 1-D unsteady flow model. The method developed is effective for flood forecasting, and can be used for practical operation in the flood forecasting.
A comparison of 1D and 2D LSTM architectures for the recognition of handwritten Arabic
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.
Transparent Conducting Electrodes based on 1D and 2D Ag Nanogratings for Organic Photovoltaics
Zeng, Beibei; Bartoli, Filbert J
2014-01-01
The optical and electrical properties of optically-thin one-dimensional (1D) Ag nanogratings and two-dimensional (2D) Ag nanogrids are studied, and their use as transparent electrodes in organic photovoltaics are explored. A large broadband and polarization-insensitive optical absorption enhancement in the organic light-harvesting layers is theoretically and numerically demonstrated using either single-layer 2D Ag nanogrids or two perpendicular 1D Ag nanogratings, and is attributed to the excitation of surface plasmon resonances and plasmonic cavity modes. Total photon absorption enhancements of 150% and 200% are achieved for the optimized single-layer 2D Ag nanogrids and double (top and bottom) perpendicular 1D Ag nanogratings, respectively.
Periodic Properties of 1D FE Discrete Models in High Frequency Dynamics
Directory of Open Access Journals (Sweden)
A. Żak
2016-01-01
Full Text Available Finite element discrete models of various engineering 1D structures may be considered as structures of certain periodic characteristics. The source of this periodicity comes from the discontinuity of stress/strain field between the elements. This behaviour remains unnoticeable, when low frequency dynamics of these structures is investigated. At high frequency regimes, however, its influence may be strong enough to dominate calculated structural responses distorting or even falsifying them completely. In this paper, certain computational aspects of structural periodicity of 1D FE discrete models are discussed by the authors. In this discussion, the authors focus their attention on an exemplary problem of 1D rod modelled according to the elementary theory.
PC-1D installation manual and user's guide
Energy Technology Data Exchange (ETDEWEB)
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.
Spin Excitations and Phonon Anomaly in Quasi-1D Spiral Magneti CuBr2
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.
Solution to 1-D consolidation of non-homogeneous soft clay
Institute of Scientific and Technical Information of China (English)
XIE Kang-he; WEN Jie-bang; XIA Jian-zhong
2005-01-01
In this work, semi-analytical methods were used to solve the problem of 1-D consolidation of non-homogeneous soft clay with spatially varying coefficients of permeability and compressibility. The semi-analytical solution was programmed and then verified by comparison with the obtained analytical solution of a special case. Based on the results of some computations and comparisons with the 1-D homogeneous consolidation (by Terzaghi) and the 1-D non-linear consolidation theory (by Davis et al.)of soft clay, some diagrams were prepared and the relevant consolidation behavior of non-homogeneous soils is discussed. It was shown that the result obtained differs greatly from Terzaghi's theory and that of the non-linear consolidation theory when the coefficients of permeability and compressibility vary greatly.
DEVELOPMENT OF COUPLED 1D-2D MATHEMATICAL MODELS FOR TIDAL RIVERS
Institute of Scientific and Technical Information of China (English)
XU Zu-xin; YIN Hai-long
2004-01-01
Some coupled 1D-2D hydrodynamic and water quality models depicting tidal water bodies with complex topography were presented. For the coupled models, finite element method was used to solve the governing equations so as to study tidal rivers with complex topography. Since the 1D and 2D models were coupled, the principle of model coupling was proposed to account appropriately for the factors of water level, flow and pollutant flux and the related dynamical behavior was simulated. Specifically the models were used to probe quantitative pollution contribution of receiving water from neighboring Jiangsu and Zhejiang Provinces to the pollution in the Huangpu River passing through Shanghai City. Numerical examples indicated that the developed coupled 1D-2D models are applicable in tidal river network region of Shanghai.
Introduction to adaptive arrays
Monzingo, Bob; Haupt, Randy
2011-01-01
This second edition is an extensive modernization of the bestselling introduction to the subject of adaptive array sensor systems. With the number of applications of adaptive array sensor systems growing each year, this look at the principles and fundamental techniques that are critical to these systems is more important than ever before. Introduction to Adaptive Arrays, 2nd Edition is organized as a tutorial, taking the reader by the hand and leading them through the maze of jargon that often surrounds this highly technical subject. It is easy to read and easy to follow as fundamental concept
Carboxyl terminus-truncated α1D-adrenoceptors inhibit the ERK pathway.
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
Modelling turbulent vertical mixing sensitivity using a 1-D version of NEMO
Directory of Open Access Journals (Sweden)
G. Reffray
2014-08-01
Full Text Available Through two numerical experiments, a 1-D vertical model called NEMO1D was used to investigate physical and numerical turbulent-mixing behaviour. The results show that all the turbulent closures tested (k + l from Blanke and Delecluse, 1993 and two equation models: Generic Lengh Scale closures from Umlauf and Burchard, 2003 are able to correctly reproduce the classical test of Kato and Phillips (1969 under favourable numerical conditions while some solutions may diverge depending on the degradation of the spatial and time discretization. The performances of turbulence models were then compared with data measured over a one-year period (mid-2010 to mid-2011 at the PAPA station, located in the North Pacific Ocean. The modelled temperature and salinity were in good agreement with the observations, with a maximum temperature error between −2 and 2 °C during the stratified period (June to October. However the results also depend on the numerical conditions. The vertical RMSE varied, for different turbulent closures, from 0.1 to 0.3 °C during the stratified period and from 0.03 to 0.15 °C during the homogeneous period. This 1-D configuration at the PAPA station (called PAPA1D is now available in NEMO as a reference configuration including the input files and atmospheric forcing set described in this paper. Thus, all the results described can be recovered by downloading and launching PAPA1D. The configuration is described on the NEMO site (http://www.nemo-ocean.eu/Using-NEMO/Configurations/C1D_PAPA. This package is a good starting point for further investigation of vertical processes.
Column Testing and 1D Reactive Transport Modeling to Evaluate Uranium Plume Persistence Processes
Energy Technology Data Exchange (ETDEWEB)
Johnson, Raymond H. [Navarro Research and Engineering, Inc.; Morrison, Stan [Navarro Research and Engineering, Inc.; Morris, Sarah [Navarro Research and Engineering, Inc.; Tigar, Aaron [Navarro Research and Engineering, Inc.; Dam, William [U.S. Department of Energy, Office of Legacy Management; Dayvault, Jalena [U.S. Department of Energy, Office of Legacy Management
2016-04-26
Motivation for Study: Natural flushing of contaminants at various U.S. Department of Energy Office of Legacy Management sites is not proceeding as quickly as predicted (plume persistence) Objectives: Help determine natural flushing rates using column tests. Use 1D reactive transport modeling to better understand the major processes that are creating plume persistence Approach: Core samples from under a former mill tailings area Tailings have been removed. Column leaching using lab-prepared water similar to nearby Gunnison River water. 1D reactive transport modeling to evaluate processes
Refractive index sensor based on a 1D photonic crystal in a microfluidic channel
DEFF Research Database (Denmark)
Rodrigues de Sousa Nunes, Pedro André; Mortensen, Asger; Kutter, Jörg Peter;
2010-01-01
A refractive index sensor has been fabricated in silicon oxynitride by standard UV lithography and dry etching processes. The refractive index sensor consists of a 1D photonic crystal (PhC) embedded in a microfluidic channel addressed by fiber-terminated planar waveguides. Experimental demonstrat......A refractive index sensor has been fabricated in silicon oxynitride by standard UV lithography and dry etching processes. The refractive index sensor consists of a 1D photonic crystal (PhC) embedded in a microfluidic channel addressed by fiber-terminated planar waveguides. Experimental...
AM1/d parameters for Magnesium in Metalloenzymes. Journal of Chemical Theory and Computation
Energy Technology Data Exchange (ETDEWEB)
Imhof, Petra [University of Heidelberg; Noe, F [University of Heidelberg; Fischer, S. [University of Heidelberg; Smith, Jeremy C [ORNL
2006-06-01
AM1/d parameters are derived for magnesium, optimized for modeling reactions in metalloenzymes. The parameters are optimized with a Monte Carlo procedure so as to reproduce the geometries and energies of a training set calculated with density functional theory. The training set consists of compounds with magnesium coordinated to the oxygen atom of typical biological ligands. Optimization of AM1 parameters without extension to d functions leaves serious errors. The new AM1/d parameters provide a clear improvement in accuracy compared to the standard semiempirical methods AM1 and MNDO/d and will be particularly useful for modeling reactions in large biological systems at low computational cost.
Characterization of 5-HT1D receptor binding sites in post-mortem human brain cortex.
Martial, J; de Montigny, C; Cecyre, D; Quirion, R
1991-01-01
The present study provides further evidence for the presence of serotonin1D (5-HT1D) receptors in post-mortem human brain. Receptor binding parameters in temporal cortex homogenates were assessed using [3H]5-HT in the presence of 100 nM 8-OH-DPAT, 1 microM propranolol and 1 microM mesulergine to prevent labelling of the 5-HT1A, 5-HT1B and 5-HT1C sites, respectively. Under these conditions, [3H]5-HT apparently bound to a class of high affinity (Kd = 5.0 +/- 1.0 nM) low capacity (Bmax = 96 +/- ...
Dopamine D1-D2 receptor heteromer signaling pathway in the brain: emerging physiological relevance
Directory of Open Access Journals (Sweden)
Hasbi Ahmed
2011-06-01
Full Text Available Abstract Dopamine is an important catecholamine neurotransmitter modulating many physiological functions, and is linked to psychopathology of many diseases such as schizophrenia and drug addiction. Dopamine D1 and D2 receptors are the most abundant dopaminergic receptors in the striatum, and although a clear segregation between the pathways expressing these two receptors has been reported in certain subregions, the presence of D1-D2 receptor heteromers within a unique subset of neurons, forming a novel signaling transducing functional entity has been shown. Recently, significant progress has been made in elucidating the signaling pathways activated by the D1-D2 receptor heteromer and their potential physiological relevance.
Protein Functionalized Nanodiamond Arrays
Directory of Open Access Journals (Sweden)
Liu YL
2010-01-01
Full Text Available Abstract Various nanoscale elements are currently being explored for bio-applications, such as in bio-images, bio-detection, and bio-sensors. Among them, nanodiamonds possess remarkable features such as low bio-cytotoxicity, good optical property in fluorescent and Raman spectra, and good photostability for bio-applications. In this work, we devise techniques to position functionalized nanodiamonds on self-assembled monolayer (SAMs arrays adsorbed on silicon and ITO substrates surface using electron beam lithography techniques. The nanodiamond arrays were functionalized with lysozyme to target a certain biomolecule or protein specifically. The optical properties of the nanodiamond-protein complex arrays were characterized by a high throughput confocal microscope. The synthesized nanodiamond-lysozyme complex arrays were found to still retain their functionality in interacting with E. coli.
Permutations of cubical arrays
International Nuclear Information System (INIS)
The structure constants of an algebra determine a cube called the cubical array associated with the algebra. The permuted indices of the cubical array associated with a finite semifield generate new division algebras. We do not not require that the algebra be finite and ask 'Is it possible to choose a basis for the algebra such any permutation of the indices of the structure constants leaves the algebra unchanged?' What are the associated algebras? Author shows that the property 'weakly quadratic' is invariant under all permutations of the indices of the corresponding cubical array and presents two algebras for which the cubical array is invariant under all permutations of the indices.
Flexible retinal electrode array
Energy Technology Data Exchange (ETDEWEB)
Okandan, Murat (Albuquerque, NM); Wessendorf, Kurt O. (Albuquerque, NM); Christenson, Todd R. (Albuquerque, NM)
2006-10-24
An electrode array which has applications for neural stimulation and sensing. The electrode array can include a large number of electrodes each of which is flexibly attached to a common substrate using a plurality of springs to allow the electrodes to move independently. The electrode array can be formed from a combination of bulk and surface micromachining, with electrode tips that can include an electroplated metal (e.g. platinum, iridium, gold or titanium) or a metal oxide (e.g. iridium oxide) for biocompatibility. The electrode array can be used to form a part of a neural prosthesis, and is particularly well adapted for use in an implantable retinal prosthesis where the electrodes can be tailored to provide a uniform gentle contact pressure with optional sensing of this contact pressure at one or more of the electrodes.
Expandable LED array interconnect
Yuan, Thomas Cheng-Hsin; Keller, Bernd
2011-03-01
A light emitting device that can function as an array element in an expandable array of such devices. The light emitting device comprises a substrate that has a top surface and a plurality of edges. Input and output terminals are mounted to the top surface of the substrate. Both terminals comprise a plurality of contact pads disposed proximate to the edges of the substrate, allowing for easy access to both terminals from multiple edges of the substrate. A lighting element is mounted to the top surface of the substrate. The lighting element is connected between the input and output terminals. The contact pads provide multiple access points to the terminals which allow for greater flexibility in design when the devices are used as array elements in an expandable array.
International Nuclear Information System (INIS)
Highlights: • The Ni nanowires with different diameters have been fabricated in the AAO templates. • The high-temperature magnetic properties of 1D nanowire arrays are reported. • The templates can suppress growth of nanowires during high-temperature measurements. • The Curie temperature follows a finite-size scaling theory with λ = 0.926 and ξ0 = 17.35 Å. - Abstract: Ordered Ni nanowire arrays were successfully fabricated by electrochemical deposition method based on the anodized aluminum oxide (AAO) templates. It was found that the diameter of nanowire can be well controlled by the pore size of AAO template. The nanowire arrays with 50 nm in diameter were characterized by X-ray diffraction, electron microscopy, and physical properties measurement system. The results indicate that the polycrystalline Ni nanowire arrays exhibit obvious magnetic anisotropy, and the easy magnetization direction is oriented along the nanowire axial direction. By measuring the temperature dependence of magnetization, the Curie temperatures of nanowires with different sizes were obtained. The Curie temperature of one-dimensionality (1D) nanowire arrays is found to decrease with decreasing diameter and follow a finite-size scaling theory with λ = 0.926 and ξ0 = 17.35 Å. The fitting exponent of 1D nanowire arrays is close to the nanoparticles (zero-dimensionality, 0D) result and two-dimensionality (2D) nano-films result
Henzinger, Thomas A.; Hottelier, Thibaud; Kovács, Laura; Rybalchenko, Andrey
2010-01-01
This paper presents Aligators, a tool for the generation of universally quantified array invariants. Aligators leverages recurrence solving and algebraic techniques to carry out inductive reasoning over array content. The Aligatorsâ€™ loop extraction module allows treatment of multi-path loops by exploiting their commutativity and serializability properties. Our experience in applying Aligators on a collection of loops from open source software projects indicates the applicability of recurren...
Capdevila Cascante, Santiago; Jofre Roca, Lluís; Romeu Robert, Jordi; Bolomey, J.Ch
2010-01-01
In this paper the use of RFID tags for the measurement of physical parameters in a distributed set of points is presented. Experimental results for two different scenarios are presented; the first uses a 2D RFID array to measure the field distribution of a radiating aperture, while the second detects the change in the close environment of an array of RFID tags to determine the water level of a container.
Microphone arrays fundamentals
Embrechts, Jean-Jacques
2011-01-01
Microphone arrays are essentially directional sensors. They are therefore mainly used for locating, identifying, isolating, measuring and recording individual sound sources. The main principles governing the directivity of microphone arrays are reviewed: phase differences between signals create constructive and destructive interferences, depending on the direction of the sound source. Moreover, signal processing is applied to provide “beamforming”, i.e. beam shaping and steering. Contrary to ...
International Nuclear Information System (INIS)
Exact numerical calculation of ensemble averaged length-scale dependent conductance for the 1D Anderson model is shown to support an earlier conjecture for a conductance minimum. Numerical results can be understood in terms of the Thouless expression for the conductance and the Wigner level-spacing statistics. (author). 8 refs, 2 figs
1D Cahn-Hilliard equation: Ostwald ripening and application to modulated phase systems
Villain-Guillot, Simon
2008-01-01
Using an approximate analytical solution of the Cahn-Hilliard equation describing the coalescence during a first order phase transition, we compute the characteristic time for one step of period doubling in Langer's self similar scenario for Ostwald ripening. As an application, we compute the thermodynamically stable period of a 1D modulated phase pattern.
Quantized 1D- and 2D optical molasses: Laser cooling and spectrum of resonance fluorescene
International Nuclear Information System (INIS)
We present results for laser cooling of optical molasses and the spectrum of resonance fluorescene based on a fully quantum mechanical treatment of the atomic center-of-mass motion for 1D and 2D laser configurations. Our calculations based on recently developed wave function simulations of the quantum master equation for laser cooling
Solvent-free porous framework resulted from 3D entanglement of 1D zigzag coordination polymer
Kole, Goutam Kumar Umar
2010-01-01
A solvent-free porous metal organic framework is constructed by the 3D entanglement of 1D zigzag coordination polymeric chains. The role of solvents and the effect of reaction conditions on such unique entanglement are addressed. © 2010 The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.
Influence of lipid rafts on CD1d presentation by dendritic cells
DEFF Research Database (Denmark)
Peng, Wei; Martaresche, Cecile; Escande-Beillard, Nathalie; Cédile, Oriane; Reynier-Vigouroux, Anne; Boucraut, Jose
Our main objective was to analyze the role of lipid rafts in the activation of Valpha-14(-) and Valpha-14(+) T hybridomas by dendritic cells. We showed that activation of Valpha-14(+) hybridomas by dendritic cells or other CD1d-expressing cells was altered by disruption of lipid rafts with the...
Thermodynamics of 1D N-Component Bariev Model Under Open Boundary Conditions
Institute of Scientific and Technical Information of China (English)
WANG Chun; KE San-Min; YUE Rui-Hong
2006-01-01
The thermodynamic Bethe ansatz equations and free energy for 1D N-component Bariev model under open boundary conditions are derived based on the string hypothesis for both, a repulsive and an attractive interaction.These equations are discussed in some limiting cases, such as the ground state, weak and strong couplings.
Minimal representations of supersymmetry and 1D N-extended σ-models
International Nuclear Information System (INIS)
We discuss the minimal representations of the 1D N-Extended Supersymmetry algebra (the Z2-graded symmetry algebra of the Supersymmetric Quantum Mechanics) linearly realized on a finite number of fields depending on a real parameter t, the time. Their knowledge allows to construct one-dimensional sigma-models with extended off-shell supersymmetries without using superfields (author)
2D/1D approximations to the 3D neutron transport equation. I: Theory
International Nuclear Information System (INIS)
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)
HYDRUS-1D Modeling of an Irrigated Agricultural Plot with Application to Aquifer Recharge Estimation
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...
On the self-assembly of TiOx into 1D NP network nanostructures
International Nuclear Information System (INIS)
Here, we report for the first time a ‘ligand free’ method of designing 1D TiOx supramolecular network materials, which starts from Ti bare metal powder. Each TiOx oxidation step has been carefully investigated with different analytical techniques, including high resolution transmission electron microscopy/high resolution scanning electron microscopy (HRTEM/HRSEM), x-ray photoelectron spectroscopy (XPS), Raman spectroscopy and superconducting quantum interference device (SQUID) measurements. The self-assembly of TiOx nanoparticles (NPs) into 1D supramolecular nanoparticle networks is induced by the formation of mixed valent TiII,III species. The synthesis starts with etching a bare Ti surface, followed by a continuous oxidation of TiOx clusters and NPs, and it finally ends with the self-assembly into rigid 1D NPs chains. Today, such self-assembled 1D NP TiOx network materials are bridging the gap between the nanoscale and the macroscopic material world and will further provide interesting research opportunities. (fast track communication)
A South American Prehistoric Mitogenome: Context, Continuity, and the Origin of Haplogroup C1d.
Sans, Mónica; Figueiro, Gonzalo; Hughes, Cris E; Lindo, John; Hidalgo, Pedro C; Malhi, Ripan S
2015-01-01
Based on mitochondrial DNA (mtDNA), it has been estimated that at least 15 founder haplogroups peopled the Americas. Subhaplogroup C1d3 was defined based on the mitogenome of a living individual from Uruguay that carried a lineage previously identified in hypervariable region I sequences from ancient and modern Uruguayan individuals. When complete mitogenomes were studied, additional substitutions were found in the coding region of the mitochondrial genome. Using a complete ancient mitogenome and three modern mitogenomes, we aim to clarify the ancestral state of subhaplogroup C1d3 and to better understand the peopling of the region of the Río de la Plata basin, as well as of the builders of the mounds from which the ancient individuals were recovered. The ancient mitogenome, belonging to a female dated to 1,610±46 years before present, was identical to the mitogenome of one of the modern individuals. All individuals share the mutations defining subhaplogroup C1d3. We estimated an age of 8,974 (5,748-12,261) years for the most recent common ancestor of C1d3, in agreement with the initial peopling of the geographic region. No individuals belonging to the defined lineage were found outside of Uruguay, which raises questions regarding the mobility of the prehistoric inhabitants of the country. Moreover, the present study shows the continuity of Native lineages over at least 6,000 years. PMID:26509686
A derivation of Akcasu's 'MLP' equations for 1-D particle transport in stochastic media
International Nuclear Information System (INIS)
This paper presents a new derivation of Akcasu's Modified Levermore-Pomraning (MLP) model for estimating the ensemble-averaged angular flux for particle transport problems in 1-D geometrically random media. The significant new feature of the MLP equations is that, unlike the earlier Levermore-Pomraning (LP) model, the MLP equations are exact for certain classes of problems with scattering. (authors)
On the extrema of a nonconvex functional with double-well potential in 1D
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.
D1D5 systems and AdS/CFT correspondences with 16 supercharges
Gava, E; Morales, J F; Narain, Kumar S; Gava, Edi; Hammou, Amine B.; Morales, Jose F.; Narain, Kumar S.
2002-01-01
We study the spectra of BPS excitations of D1D5 bound states in a class of free orbifolds/orientifolds of type IIB theory and its dual descriptions in terms of chiral primaries of the corresponding $AdS_3$ supergravities.
Fresnel Lenses fabricated by femtosecond laser micromachining on Polymer 1D Photonic Crystal
Directory of Open Access Journals (Sweden)
Guduru Surya S.K.
2013-11-01
Full Text Available We report the fabrication of micro Fresnel lenses by femtosecond laser surface ablation on polymer 1D photonic crystals. This device is designed to focus the transmitted wavelength of the photonic crystal and filter the wavelengths corresponding to the photonic band gap region. Integration of such devices in a wavelength selective light harvesting and filtering microchip can be achieved.
CD1d-restricted peripheral T cell lymphoma in mice and humans.
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
Hays, Brian; Wehres, Nadine; Deprince, Bridget Alligood; Roy, Althea A. M.; Laas, Jacob; Widicus Weaver, Susanna L.
2015-06-01
While both the number of detected interstellar molecules and their chemical complexity continue to increase, understanding of the processes leading to their formation is lacking. Our research group combines laboratory spectroscopy, observational astronomy, and astrochemical modeling for an interdisciplinary examination of the chemistry of star and planet formation. This talk will focus on our laboratory studies of O(^1D) insertion reactions with organic molecules to produce molecules of astrophysical interest. By employing these reactions in a supersonic expansion, we are able to produce interstellar organic reaction intermediates that are unstable under terrestrial conditions; we then probe the products using millimeter and submillimeter spectroscopy. We benchmarked this setup using the well-studied O(^1D) + methane reaction to form methanol. After optimizing methanol production, we moved on to study the O(^1D) + ethylene reaction to form vinyl alcohol (CH_2CHOH), and the O(^1D) + methyl amine reaction to form aminomethanol (NH_2CH_2OH). Vinyl alcohol measurements have now been extended up to 450 GHz, and the associated spectral analysis is complete. A possible detection of aminomethanol has also been made, and continued spectral studies and analysis are underway. We will present the results from these experiments and discuss future applications of these molecular and spectroscopic techniques.
Thin film encapsulated 1D thermoelectric detector in an IR microspectrometer
H. Wu; Emadi, A.; De Graaf, G.; Wolffenbuttel, R F
2010-01-01
A thermopile-based detector array for use in a miniaturized Infrared (IR) spectrometer has been designed and fabricated using CMOS compatible MEMS technology. The emphasis is on the optimal of the detector array at the system level, while considering the thermal design, the dimensional constraints of a design on a chip and the CMOS compatibility. The resolving power is maximized by spacing the Thermo-Electric (TE) elements at an as narrow as possible pitch, which is limited by processing cons...
High-resolution medical ultrasound arrays using smart materials technology
Bridger, Keith; Caldwell, Paul J.; Kuhn, Phillip; Winzer, Stephen R.
1996-05-01
Current ultrasound images have relatively low contrast (high levels of clutter) and resolution. Image quality could be dramatically improved if 2D ultrasound transducer arrays were available to perform the scans. These improvements would come from reducing clutter by eliminating target echoes that the beam width of a 1D array causes to be superimposed on a scan plane, and enhancing resolution by enabling the use of algorithms which correct the wavefront distortion introduced by propagation through tissue. The advent of 2D arrays would also enable 3D images to be displayed--eventually in real time. The fabrication of 2D ultrasound arrays is, however, very difficult. This stems from the acoustic requirements of the array (aperture, pitch and element size) which combine together to dictate large numbers (> 1000) of very-low capacitance (capacitance and impedance mismatch. This paper will show how the development of composite smart materials involving the integration of electromechanical elements with electronics is being extended to the development of relatively-inexpensive high-sensitivity 2D ultrasound arrays.
Ka-band MMIC beam steered transmitter array
Rascoe, D. L.; Riley, A. L.; Huang, J.; Lubecke, V.; Duffy, L.
1989-01-01
A 32-GHz six-element linear transmitter array utilizing monolithic microwave integrated circuit (MMIC) phase shifters and power amplifiers was designed and tested as part of the development of a spacecraft array feed for NASA deep-space communications applications. Measurements of the performance of individual phase shifters, power amplifiers, and microstrip radiators were carried out, and electronic beam steering of the linear array was demonstrated. The switched-line phase shifters were accurate to within 7 percent on average and the power amplifier 1-dB compressed output power varied over 0.3 dB. The array had a beamwidth of 7.5 deg and demonstrated acceptable beam steering over + or - 8 deg. From the results, it can be concluded that this MMIC phased array has adequate beam-scanning capability for use in the two-dimensional array. The areas that need to be improved are the efficiency of the MMIC power amplifier and the insertion loss of the MMIC phase shifter.
A Mobile Ferromagnetic Shape Detection Sensor Using a Hall Sensor Array and Magnetic Imaging
Directory of Open Access Journals (Sweden)
Nashiren Farzilah Mailah
2011-11-01
Full Text Available This paper presents a Mobile Hall Sensor Array system for the shape detection of ferromagnetic materials that are embedded in walls or floors. The operation of the Mobile Hall Sensor Array system is based on the principle of magnetic flux leakage to describe the shape of the ferromagnetic material. Two permanent magnets are used to generate the magnetic flux flow. The distribution of magnetic flux is perturbed as the ferromagnetic material is brought near the permanent magnets and the changes in magnetic flux distribution are detected by the 1-D array of the Hall sensor array setup. The process for magnetic imaging of the magnetic flux distribution is done by a signal processing unit before it displays the real time images using a netbook. A signal processing application software is developed for the 1-D Hall sensor array signal acquisition and processing to construct a 2-D array matrix. The processed 1-D Hall sensor array signals are later used to construct the magnetic image of ferromagnetic material based on the voltage signal and the magnetic flux distribution. The experimental results illustrate how the shape of specimens such as square, round and triangle shapes is determined through magnetic images based on the voltage signal and magnetic flux distribution of the specimen. In addition, the magnetic images of actual ferromagnetic objects are also illustrated to prove the functionality of Mobile Hall Sensor Array system for actual shape detection. The results prove that the Mobile Hall Sensor Array system is able to perform magnetic imaging in identifying various ferromagnetic materials.
Institute of Scientific and Technical Information of China (English)
YANG Xiao-Gang; LI Dong-Sheng; FU Feng; WU Ya-Pan; WANG Ji-Jiang; WANG Yao-Yu
2008-01-01
The hydrothermal reactions of AgNO3, 2,2'-bipyridyl, and benzophenone-2,4'-dicarboxylic acid gave rise to two benzophenone-2,4'-dicarboxylic acid). The two compounds are extended by hydrogen bonds in two different apbonding between H2L ligands and water molecules, then extended to a 3D supramolecular architecture. Compound 2 possesses 3D supramolecular architecture containing 1D open channels, which are driven due to the strong H-bonding interactions occurring between the HL anions and water molecules; interestingly, [Ag(bpy)2]+ cations vestigated, the emission maxima for 2 exhibits red-shift compared with that of free ligand and 1 due to chelating effect of the 2,2'-bipyridine ligand to the silver ion and the presence of aromatic π-packing.
International Nuclear Information System (INIS)
To reduce the clogging of smoke on the HEPA filters under the fire accident, some of ventilation systems in the plant are equipped with the pre-filters in front of the HEPA filters for collecting the relatively large smoke particles. Appropriate correspondence such as the exchange of the pre-filter is important for confinement of radioactive materials in the ventilation system under the fire accident. To study smoke generation behavior due to the burnable wastes and clogging properties of the ventilation filters by smoke loading, the verification test has been performed. The cell ventilation system analysis code, CELVA-1D was used for analysis of smoke generation and the rising of pressure drop at both the pre-filter and the HEPA filter. With the change of source term, the breakage of time of the pre-filter was also estimated. (author)
Optimizing Chemical Sensor Array Sizes
International Nuclear Information System (INIS)
Optimal selection of array sensors for a chemical sensing application is a nontrivial task. It is commonly believed that ''more is better'' when choosing the number of sensors required to achieve good chemical selectivity. However, cost and system complexity issues point towards the choice of small arrays. A quantitative array optimization is carried out to explore the selectivity of arrays of partially-selective chemical sensors as a function of array size. It is shown that modest numbers (dozens) of target analytes are completely distinguished with a range of arrays sizes. However, the array selectivity and the robustness against sensor sensitivity variability are significantly degraded if the array size is increased above a certain number of sensors, so that relatively small arrays provide the best performance. The results also suggest that data analyses for very large arrays of partially-selective sensors will be optimized by separately anal yzing small sensor subsets
Rutledge, D. B.; Muha, M. S.
1982-01-01
Many millimeter and far-infrared imaging systems are limited in sensitivity and speed because they depend on a single scanned element. Because of recent advances in planar detectors such as Schottky diodes, superconducting tunnel junctions, and microbolometers, an attractive approach to this problem is a planar antenna array with integrated detectors. A planar line antenna array and optical system for imaging has been developed. The significant advances are a 'reverse-microscope' optical configuration and a modified bow-tie antenna design. In the 'reverse-microscope' configuration, a lens is attached to the bottom of the substrate containing the antennas. Imaging is done through the substrate. This configuration eliminates the troublesome effects of substrate surface waves. The substrate lens has only a single refracting surface, making possible a virtually aplanatic system, with little spherical aberration or coma. The array is characterized by an optical transfer function that is easily measured. An array with 19 dB crosstalk levels between adjacent antennas has been tested and it was found that the array captured 50 percent of the available power. This imaging system was diffraction limited.
Wormhole spacetimes, CTCs and chronology protection in a dc-SQUID array
Sabín, Carlos
2016-01-01
We present an analog quantum simulator of spacetimes containing traversable wormholes. A suitable spatial dependence in the external bias of a dc-SQUID array mimics the propagation of light in a 1D wormhole background. The impedance of the array places severe limitations on the type of spacetime that we are able to implement. However, we find that wormhole throat radius in the sub-mm range are achievable. We show how to modify this spacetime in order to allow the existence of closed timelike curves. The quantum fluctuations of the phase associated to the finite array impedance might be seen as an analogue of Hawking's chronology protection mechanism.
Lameris, Roeland; de Bruin, Renée C G; van Bergen En Henegouwen, Paul M P; Verheul, Henk M; Zweegman, Sonja; de Gruijl, Tanja D; van der Vliet, Hans J
2016-09-01
Ligation of the CD1d antigen-presenting molecule by monoclonal antibodies (mAbs) can trigger important biological functions. For therapeutic purposes camelid-derived variable domain of heavy-chain-only antibodies (VHH) have multiple advantages over mAbs because they are small, stable and have low immunogenicity. Here, we generated 21 human CD1d-specific VHH by immunizing Lama glama and subsequent phage display. Two clones induced maturation of dendritic cells, one clone induced early apoptosis in CD1d-expressing B lymphoblasts and multiple myeloma cells, and another clone blocked recognition of glycolipid-loaded CD1d by CD1d-restricted invariant natural killer T (iNKT) cells. In contrast to reported CD1d-specific mAbs, these CD1d-specific VHH have the unique characteristic that they induce specific and well-defined biological effects. This feature, combined with the above-indicated general advantages of VHH, make the CD1d-specific VHH generated here unique and useful tools to exploit both CD1d ligation as well as disruption of CD1d-iNKT interactions in the treatment of cancer or inflammatory disorders. PMID:27312006
International Nuclear Information System (INIS)
Protein phosphatase magnesium/manganese-dependent 1D (PPM1D) is a p53-induced phosphatase that functions as a negative regulator of stress response pathways and has oncogenic properties. However, the functional role of PPM1D in bladder cancer (BC) remains largely unknown. In the present study, lentivirus vectors carrying small hairpin RNA (shRNA) targeting PPM1D were used to explore the effects of PPM1D knockdown on BC cell proliferation and tumorigenesis. shRNA-mediated knockdown of PPM1D significantly inhibited cell growth and colony forming ability in the BC cell lines 5637 and T24. Flow cytometric analysis showed that PPM1D silencing increased the proportion of cells in the G0/G1 phase. Downregulation of PPM1D also inhibited 5637 cell tumorigenicity in nude mice. The results of the present study suggest that PPM1D plays a potentially important role in BC tumorigenicity, and lentivirus-mediated delivery of shRNA against PPM1D might be a promising therapeutic strategy for the treatment of BC
Energy Technology Data Exchange (ETDEWEB)
Wang, W. [Institute of Urology, Huashan Hospital, Fudan University, Shanghai (China); Department of the Intensive Care Unit, Huashan Hospital, Fudan University, Shanghai (China); Zhu, H. [Department of the Intensive Care Unit, Huashan Hospital, Fudan University, Shanghai (China); Zhang, H.; Zhang, L. [Department of Urology, Huashan Hospital, Fudan University, Shanghai (China); Ding, Q.; Jiang, H. [Institute of Urology, Huashan Hospital, Fudan University, Shanghai (China); Department of Urology, Huashan Hospital, Fudan University, Shanghai (China)
2014-09-23
Protein phosphatase magnesium/manganese-dependent 1D (PPM1D) is a p53-induced phosphatase that functions as a negative regulator of stress response pathways and has oncogenic properties. However, the functional role of PPM1D in bladder cancer (BC) remains largely unknown. In the present study, lentivirus vectors carrying small hairpin RNA (shRNA) targeting PPM1D were used to explore the effects of PPM1D knockdown on BC cell proliferation and tumorigenesis. shRNA-mediated knockdown of PPM1D significantly inhibited cell growth and colony forming ability in the BC cell lines 5637 and T24. Flow cytometric analysis showed that PPM1D silencing increased the proportion of cells in the G0/G1 phase. Downregulation of PPM1D also inhibited 5637 cell tumorigenicity in nude mice. The results of the present study suggest that PPM1D plays a potentially important role in BC tumorigenicity, and lentivirus-mediated delivery of shRNA against PPM1D might be a promising therapeutic strategy for the treatment of BC.
FEL phased array configurations
Shellan, Jeffrey B.
1986-01-01
The advantages and disadvantages of various phased array and shared aperture concepts for FEL configurations are discussed. Consideration is given to the characteristics of intra- and inter-micropulse phasing; intra-macropulse phasing; an internal coupled resonator configuration; and an injection locked oscillator array. The use of a master oscillator power amplifier (MOPA) configuration with multiple or single master oscillators for FELs is examined. The venetian blind, rotating plate, single grating, and grating rhomb shared aperture concepts are analyzed. It is noted that the shared aperture approach using a grating rhomb and the MOPA concept with a single master oscillator and a coupled resonator are useful for FEL phased array configurations; and the MOPA concept is most applicable.
Static sign language recognition using 1D descriptors and neural networks
Solís, José F.; Toxqui, Carina; Padilla, Alfonso; Santiago, César
2012-10-01
A frame work for static sign language recognition using descriptors which represents 2D images in 1D data and artificial neural networks is presented in this work. The 1D descriptors were computed by two methods, first one consists in a correlation rotational operator.1 and second is based on contour analysis of hand shape. One of the main problems in sign language recognition is segmentation; most of papers report a special color in gloves or background for hand shape analysis. In order to avoid the use of gloves or special clothing, a thermal imaging camera was used to capture images. Static signs were picked up from 1 to 9 digits of American Sign Language, a multilayer perceptron reached 100% recognition with cross-validation.
Design, implementation and analysis of fully digital 1-D controllable multiscroll chaos
Mansingka, Abhinav S.
2011-12-01
This paper introduces the fully digital implementation of a 1-D multiscroll chaos generator based on a staircase nonlinearity in the 3rd-order jerk system using the Euler approximation. For the first time, digital design is exploited to provide real-time controllability of (i) number of scrolls, (ii) position in 1-D space, (iii) Euler step size and (iv) system parameter. The effect of variations in these fields on the maximum Lyapunov exponent (MLE) is analyzed. The system is implemented using Verilog HDL and synthesized on an Xilinx Virtex 4 FPGA, exhibiting area utilization less than 3.5% and high performance with experimentally verified throughput up to 3.33 Gbits/s. This fully digital system enables applications in modulation schemes and chaos-based cryptosystems without analog to digital conversion. © 2011 IEEE.
Positron-sensitive vacancy-type centres in the nitrides: 1D-ACAR data
Arutyunov, N. Yu.; Emtsev, V. V.; Mikhailin, A. V.; Humphreys, C. J.
2003-12-01
The measurements of one-dimensional angular correlation of the annihilation radiation (1D-ACAR) have been carried out for BN, AlN, and GaN as well as for some related materials that have been used as the reference samples for the analysis of results. The electron-positron ion radii reconstructed by 1D-ACAR for the cation and anion sublattices of the nitrides as well as the estimated average electron density around the positron suggest that: (a) the positron annihilates in the vacancy complexes NGaVN in GaN and NAlVN in AlN, and (b) the cation nearest neighbours are, probably, shifted inward to the VN vacancy where the electron density is sufficiently lower in comparison with that estimated for the bulk.
Positron-sensitive vacancy-type centres in the nitrides: 1D-ACAR data
International Nuclear Information System (INIS)
The measurements of one-dimensional angular correlation of the annihilation radiation (1D-ACAR) have been carried out for BN, AlN, and GaN as well as for some related materials that have been used as the reference samples for the analysis of results. The electron-positron ion radii reconstructed by 1D-ACAR for the cation and anion sublattices of the nitrides as well as the estimated average electron density around the positron suggest that: (a) the positron annihilates in the vacancy complexes NGaVN in GaN and NAlVN in AlN, and (b) the cation nearest neighbours are, probably, shifted inward to the VN vacancy where the electron density is sufficiently lower in comparison with that estimated for the bulk
Numerical Methods and Comparisons for 1D and Quasi 2D Streamer Propagation Models
Huang, Mengmin; Guan, Huizhe; Zeng, Rong
2016-01-01
In this work, we propose four different strategies to simulate the one-dimensional (1D) and quasi two-dimensional (2D) model for streamer propagation. Each strategy involves of one numerical method for solving Poisson's equation and another method for solving continuity equations in the models, and a total variation diminishing three-stage Runge-Kutta method in temporal discretization. The numerical methods for Poisson's equation include finite volume method, discontinuous Galerkin methods, mixed finite element method and least-squared finite element method. The numerical method for continuity equations is chosen from the family of discontinuous Galerkin methods. The accuracy tests and comparisons show that all of these four strategies are suitable and competitive in streamer simulations from the aspects of accuracy and efficiency. By applying any strategy in real simulations, we can study the dynamics of streamer propagations and influences due to the change of parameters in both of 1D and quasi 2D models. T...
Structurally unstable regular dynamics in 1D piecewise smooth maps, and circle maps
International Nuclear Information System (INIS)
Highlights: ► A discontinuous 1D map with two discontinuity points is considered. ► Dynamic behaviors are either periodic or quasiperiodic. ► Dynamics are always structurally unstable. ► Any small perturbation in one of the parameters leads to different dynamics. - Abstract: In this work we consider a simple system of piecewise linear discontinuous 1D map with two discontinuity points: X′ = aX if ∣X∣ z, where a and b can take any real value, and may have several applications. We show that its dynamic behaviors are those of a linear rotation: either periodic or quasiperiodic, and always structurally unstable. A generalization to piecewise monotone functions X′ = F(X) if ∣X∣ z is also given, proving the conditions leading to a homeomorphism of the circle.
Rotating condensed-boson gases in a 1D lattice at finite temperature
Energy Technology Data Exchange (ETDEWEB)
Hassan, Ahmed S.; Soliman, Shemi S.M., E-mail: shemisoliman@yahoo.co.uk
2015-02-15
In this paper, we study the thermodynamic properties of a rotating boson gases in a one-dimensional (1D) optical lattice at finite temperature. Our system is formed by loading three-dimensional boson-clouds into 1D optical lattice and subjected to rotate with angular velocity Ω about the z-axis (rotating condensate in a quasi-two-dimensional trap). We employ the semiclassical approximation to calculate the condensate fraction, critical temperature and the heat capacity of the system. The calculated results show that the rotating condensates in a quasi-two-dimensional have interesting properties which are absent in both three or pure two-dimensional systems. Our results can be extended to investigate the current experiments of rotating Bose–Einstein condensation produced or transferred in one-dimensional optical lattices.
Modeling of the diffraction pattern of 1D-disordered silicon carbide
International Nuclear Information System (INIS)
A method for calculating the diffraction pattern of a 1D-disordered crystal structure is considered by the example of silicon carbide. One-dimensional disordering is described using a cell setting the mutual position of all close-packed crystal layers. Two models of structure disordering during the polytypic transformation of the silicon carbide cubic modification into hexagonal are discussed. The results of the calculation of the diffraction spectrum in different stages of polytypic transformation are reported. It is shown that 1D disordering leads to the formation of a set of weak diffraction reflections. The experimentally observed changes in the diffraction pattern can be interpreted within the hypothesis on crystal structure disordering through displacement of adjacent close-packed layers.
Assessment of core thermo-hydrodynamic models of REFLA-1D with CCTF data
International Nuclear Information System (INIS)
In order to assess the core thermo-hydrodynamic models of REFLA-1D/MODE3, which is the latest version of REFLA-1D, several calculations of the core thermo-hydrodynamics have been performed for the CCTF Core-I series tests. The measured initial and boundary conditions were used for these calculations. The calculational results showed that the water accumulation model of Case 2 could predict the CCTF results fairly well as it could for the JAERI small scale facility. The calculated results for the base case and the EM tests were in good agreement with the CCTF data. The parameter effects, such as system pressure, initial clad temperature, Acc injection rate, LPCI injection rate and initial down-comer wall temperature, were predicted correctly, except for the high system pressure and the high LPCI injection rate tests. (author)
Verification and comparison of four numerical schemes for a 1D viscoelastic blood flow model.
Wang, Xiaofei; Fullana, Jose-Maria; Lagrée, Pierre-Yves
2015-01-01
A reliable and fast numerical scheme is crucial for the 1D simulation of blood flow in compliant vessels. In this paper, a 1D blood flow model is incorporated with a Kelvin-Voigt viscoelastic arterial wall. This leads to a nonlinear hyperbolic-parabolic system, which is then solved with four numerical schemes, namely: MacCormack, Taylor-Galerkin, monotonic upwind scheme for conservation law and local discontinuous Galerkin. The numerical schemes are tested on a single vessel, a simple bifurcation and a network with 55 arteries. The numerical solutions are checked favorably against analytical, semi-analytical solutions or clinical observations. Among the numerical schemes, comparisons are made in four important aspects: accuracy, ability to capture shock-like phenomena, computational speed and implementation complexity. The suitable conditions for the application of each scheme are discussed. PMID:25145651
A 1D model for the description of mixing-controlled reacting diesel sprays
Energy Technology Data Exchange (ETDEWEB)
Desantesa, J.M.; Pastor, J.V.; Garcia-Oliver, J.M.; Pastor, J.M. [CMT - Motores Termicos, Universidad Politecnica de Valencia, Camino de Vera s/n, 46022, Valencia (Spain)
2009-01-15
The paper reports an investigation on the transient evolution of diesel flames in terms of fuel-air mixing, spray penetration and combustion rate. A one-dimensional (1D) spray model, which was previously validated for inert diesel sprays, is extended to reacting conditions. The main assumptions of the model are the mixing-controlled hypothesis and the validity of self-similarity for conservative properties. Validation is achieved by comparing model predictions with both CFD gas jet simulations and experimental diesel spray measurements. The 1D model provides valuable insight into the evolution of the flow within the spray (momentum and mass fluxes, tip penetration, etc.) when shifting from inert to reacting conditions. Results show that the transient diesel flame evolution is mainly governed by two combustion-induced effects, namely the reduction in local density and the increase in flame radial width. (author)
Membranes having aligned 1-D nanoparticles in a matrix layer for improved fluid separation
Revanur, Ravindra; Lulevich, Valentin; Roh, Il Juhn; Klare, Jennifer E.; Kim, Sangil; Noy, Aleksandr; Bakajin, Olgica
2015-12-22
Membranes for fluid separation are disclosed. These membranes have a matrix layer sandwiched between an active layer and a porous support layer. The matrix layer includes 1-D nanoparticles that are vertically aligned in a porous polymer matrix, and which substantially extend through the matrix layer. The active layer provides species-specific transport, while the support layer provides mechanical support. A matrix layer of this type has favorable surface morphology for forming the active layer. Furthermore, the pores that form in the matrix layer tend to be smaller and more evenly distributed as a result of the presence of aligned 1-D nanoparticles. Improved performance of separation membranes of this type is attributed to these effects.
Magnetic Anticrossing of 1D Subbands in Coupled Ballistic Double Quantum Wires
International Nuclear Information System (INIS)
We study the low-temperature in-plane magnetoconductance of vertically coupled double quantum wires. Using a novel flip-chip technique, the wires are defined by two pairs of mutually aligned split gates on opposite sides of a s 1 micron thick AlGaAs/GaAs double quantum well heterostructure. We observe quantized conductance steps due to each quantum well and demonstrate independent control of each ID wire. A broad dip in the magnetoconductance at -6 T is observed when a magnetic field is applied perpendicular to both the current and growth directions. This conductance dip is observed only when 1D subbands are populated in both the top and bottom constrictions. This data is consistent with a counting model whereby the number of subbands crossing the Fermi level changes with field due to the formation of an anticrossing in each pair of 1D subbands
1D to 3D Crossover of a Spin-Imbalanced Fermi Gas
Revelle, Melissa C; Olsen, Ben A; Hulet, Randall G
2016-01-01
We have characterized the one-dimensional (1D) to three-dimensional (3D) crossover of a two-component spin-imbalanced Fermi gas of 6-lithium atoms in a 2D optical lattice by varying the lattice tunneling and the interactions. The gas phase separates, and we detect the phase boundaries using in situ imaging of the inhomogeneous density profiles. The locations of the phases are inverted in 1D as compared to 3D, thus providing a clear signature of the crossover. By scaling the tunneling rate with respect to the pair binding energy, we observe a collapse of the data to a universal crossover point at a scaled tunneling value of 0.016(1).
Multi-centered D1-D5 solutions at finite B-moduli
International Nuclear Information System (INIS)
We study the fate of two-centered D1-D5 systems on T4 away from the singular supergravity point in the moduli space. We do this by considering a background D1-D5 black hole with a self-dual B-field moduli turned on and treating the second center in the probe limit in this background. We find that in general marginal bound states at zero moduli become metastable at finite B-moduli, demonstrating a breaking of supersymmetry. However, we also find evidence that when the charges of both centers are comparable, the effects of supersymmetry breaking become negligible. We show that this effect is independent of string coupling and thus it should be possible to reproduce this in the CFT at weak coupling. We comment on the implications for the fuzzball proposal
Quantitative Multiscale Analysis using Different Wavelets in 1D Voice Signal and 2D Image
Shakhakarmi, Niraj
2012-01-01
Mutiscale analysis represents multiresolution scrutiny of a signal to improve its signal quality. Multiresolution analysis of 1D voice signal and 2D image is conducted using DCT, FFT and different wavelets such as Haar, Deubachies, Morlet, Cauchy, Shannon, Biorthogonal, Symmlet and Coiflet deploying the cascaded filter banks based decomposition and reconstruction. The outstanding quantitative analysis of the specified wavelets is done to investigate the signal quality, mean square error, entropy and peak-to-peak SNR at multiscale stage-4 for both 1D voice signal and 2D image. In addition, the 2D image compression performance is significantly found 93.00% in DB-4, 93.68% in bior-4.4, 93.18% in Sym-4 and 92.20% in Coif-2 during the multiscale analysis.
Iterative 2-D/1-D methods for the 3-D neutron diffusion calculation
International Nuclear Information System (INIS)
To remedy the problems arising from assembly homogenization and de-homogenization, several efforts have been made to solve directly the heterogeneous problem with a fine mesh and to reduce the computational burden by coupling 2-D planar with 1-D axial solutions using a Transverse Leakage (TL) coupling. However, the potential for a numerical instability at a small axial mesh size has been observed. Lee et al. showed that one of the two existing methods, method A, is mathematically unstable at a small mesh size while the other, method B, is always stable. They also proposed a new method for a 2-D/1-D coupling, method C, and they showed that it is always stable and it provides the best performance in terms of the convergence rate. In this paper another algorithm, method D, is proposed and its stability is also investigated
International Nuclear Information System (INIS)
West Papua region has fairly high of seismicity activities due to tectonic setting and many inland faults. In addition, the region has a unique and complex tectonic conditions and this situation lead to high potency of seismic hazard in the region. The precise earthquake hypocenter location is very important, which could provide high quality of earthquake parameter information and the subsurface structure in this region to the society. We conducted 1-D P-wave velocity using earthquake data catalog from BMKG for April, 2009 up to March, 2014 around West Papua region. The obtained 1-D seismic velocity then was used as input for improving hypocenter location using double-difference method. The relocated hypocenter location shows fairly clearly the pattern of intraslab earthquake beneath New Guinea Trench (NGT). The relocated hypocenters related to the inland fault are also observed more focus in location around the fault
FPGA Implementation of Efficient VLSI Architecture for Fixed Point 1-D DWT Using Lifting Scheme
Directory of Open Access Journals (Sweden)
Durga Sowjanya
2012-09-01
Full Text Available In this paper, a scheme for the design of area efficient and high speed pipeline VLSI architecture for the computation of fixed point 1-d discrete wavelet transform using lifting scheme is proposed. The main focus of the scheme is to reduce the number and period of clock cycles and efficient area with little or no overhead on hardware resources. The fixed point representation requires less hardware resources compared with floating point representation. The pipelining architecture speeds up the clock rate of DWT and reduced bit precision reduces the area required for implementation. The architecture has been coded in verilog HDL on Xilinx platform and the target FPGA device used is Virtex-II Pro family, XC2VP7-7board. The proposed scheme requires the least computing time for fixed point 1-D DWT and achieves theless area for implementation, compared with other architectures. So this architecture is realizable for real time processing of DWT computation applications.
Atacama Compact Array Antennas
Saito, Masao; Inatani, Junji; Nakanishi, Kouichiro; Naoi, Takahiro; Yamada, Masumi; Saito, Hiro; Ikenoue, Bungo; Kato, Yoshihiro; Morita, Kou-ichiro; Mizuno, Norikazu; Iguchi, Satoru
2011-01-01
We report major performance test results of the Atacama Compact Array (ACA) 7-m and 12-m antennas of ALMA (Atacama Large Millimeter/submillimeter Array). The four major performances of the ACA antennas are all-sky pointing (to be not more than 2.0 arcsec), offset pointing (to be < 0.6 arcsec) surface accuracy (< 25(20) micrometer for 12(7)m-antenna), stability of path-length (15 micrometer over 3 min), and high servo capability (6 degrees/s for Azimuth and 3 degrees/s for Elevation). The high...
Turner-Evans, Dan
Over the past five years, the cost of solar panels has dropped drastically and, in concert, the number of installed modules has risen exponentially. However, solar electricity is still more than twice as expensive as electricity from a natural gas plant. Fortunately, wire array solar cells have emerged as a promising technology for further lowering the cost of solar. Si wire array solar cells are formed with a unique, low cost growth method and use 100 times less material than conventional Si cells. The wires can be embedded in a transparent, flexible polymer to create a free-standing array that can be rolled up for easy installation in a variety of form factors. Furthermore, by incorporating multijunctions into the wire morphology, higher efficiencies can be achieved while taking advantage of the unique defect relaxation pathways afforded by the 3D wire geometry. The work in this thesis shepherded Si wires from undoped arrays to flexible, functional large area devices and laid the groundwork for multijunction wire array cells. Fabrication techniques were developed to turn intrinsic Si wires into full p-n junctions and the wires were passivated with a-Si:H and a-SiNx:H. Single wire devices yielded open circuit voltages of 600 mV and efficiencies of 9%. The arrays were then embedded in a polymer and contacted with a transparent, flexible, Ni nanoparticle and Ag nanowire top contact. The contact connected >99% of the wires in parallel and yielded flexible, substrate free solar cells featuring hundreds of thousands of wires. Building on the success of the Si wire arrays, GaP was epitaxially grown on the material to create heterostructures for photoelectrochemistry. These cells were limited by low absorption in the GaP due to its indirect bandgap, and poor current collection due to a diffusion length of only 80 nm. However, GaAsP on SiGe offers a superior combination of materials, and wire architectures based on these semiconductors were investigated for multijunction
Microsomal triglyceride transfer protein lipidation and control of CD1d on antigen-presenting cells
Dougan, Stephanie K.; Salas, Azucena; Rava, Paul; Agyemang, Amma; Kaser, Arthur; Morrison, Jamin; Khurana, Archana; Kronenberg, Mitchell; Johnson, Caroline; Exley, Mark; Hussain, M. Mahmood; Blumberg, Richard S.
2005-01-01
Microsomal triglyceride transfer protein (MTP), an endoplasmic reticulum (ER) chaperone that loads lipids onto apolipoprotein B, also regulates CD1d presentation of glycolipid antigens in the liver and intestine. We show MTP RNA and protein in antigen-presenting cells (APCs) by reverse transcription–polymerase chain reaction and by immunoblotting of mouse liver mononuclear cells and mouse and human B cell lines. Functional MTP, demonstrated by specific triglyceride transfer activity, is prese...
1D Cahn-Hilliard dynamics: Ostwald ripening and application to modulated phase systems
International Nuclear Information System (INIS)
We use a family of stationary solution of the Cahn-Hilliard dynamics in order to describe the coalescence during a first order phase transition. With this analytical ansatz, we compute the characteristic time for one step of period doubling in Langer's self similar scenario for Ostwald ripening. As an application, the same ansatz is also used to compute the thermodynamically stable period of a 1D modulated phase pattern, described by a Cahn-Hilliard dynamics with long range interaction terms
Finite difference approximation of control via the potential in a 1-D Schrodinger equation
Directory of Open Access Journals (Sweden)
K. Kime
2000-04-01
Full Text Available We consider the problem of steering given initial data to given terminal data via a time-dependent potential, the control, in a 1-D Schrodinger equation. We determine a condition for existence of a transferring potential within our approximation. Using Maple, we give equations for the control and also examples in which the potential is restricted to be centralized and to be a step potential.
Simulation of Tunnel Junction in Cascade Solar Cell (GaAs/Ge) Using AMPS-1D
Benmoussa Dennai; H. Ben Slimane; Helmaoui, A.
2014-01-01
The development of the tunnel junction interconnect was key the first two-terminal monolithic, multi-junction solar cell development. This paper describes simulation for the tunnel junction (GaAs) between top cell (GaAs) and bottom cell (Ge). This solar cell cascade was simulated when using one dimensional simulation program called analysis of microelectronic and photonic structures (AMPS-1D). In the simulation, the thickness of the tunnel junction layer was varied from 10 to 50 nm. By varyin...
2D/1D approximations to the 3D neutron transport equation. II: Numerical comparisons
International Nuclear Information System (INIS)
In a companion paper [1], (i) several new '2D/1D equations' are introduced as accurate approximations to the 3D Boltzmann transport equation, (ii) the simplest of these approximate equations is systematically discretized, and (iii) a theoretically stable iteration scheme is developed to solve the discrete equations. In this paper, numerical results are presented that confirm the theoretical predictions made in [1]. (authors)
Fragmentation and the Bose-glass phase transition of the disordered 1D Bose gas
Fontanesi, Luca; Wouters, Michiel; Savona, Vincenzo
2010-01-01
We investigate the superfluid-insulator quantum phase transition in a disordered 1D Bose gas in the mean field limit, by studying the probability distribution of the density. The superfluid phase is characterized by a vanishing probability to have zero density, whereas a nonzero probability marks the insulator phase. This relation is derived analytically, and confirmed by a numerical study. This fragmentation criterion is particularly suited for detecting the phase transition in experiments. ...
Shen, Maurice Y F; Perreault, Melissa L; Bambico, Francis R; Jones-Tabah, Jace; Cheung, Marco; Fan, Theresa; Nobrega, José N; George, Susan R
2015-12-01
A role for the mesolimbic dopaminergic system in the pathophysiology of depression has become increasingly evident. Specifically, brain-derived neurotrophic factor (BDNF) has been shown to be elevated in the nucleus accumbens of depressed patients and to positively contribute to depression-like behaviour in rodents. The dopamine D1-D2 receptor heteromer exhibits significant expression in NAc and has also been shown to enhance BDNF expression and signalling in this region. We therefore examined the effects of D1-D2 heteromer stimulation in rats by SKF 83959, or its inactivation by a selective heteromer-disrupting TAT-D1 peptide on depression- and anxiety-like behaviours in non-stressed animals and in animals exposed to chronic unpredictable stress. SKF 83959 treatment significantly enhanced the latency to immobility in the forced swim test, increased the latency to drink condensed milk and reduced total milk consumption in the novelty-induced hypophagia test, and additionally reduced the total time spent in the open arms in the elevated plus maze test. These pro-depressant and anxiogenic effects of SKF 83959 were consistently abolished or attenuated by TAT-D1 peptide pre-treatment, signifying the behaviours were mediated by the D1-D2 heteromer. More importantly, in animals exposed to chronic unpredictable stress (CUS), TAT-D1 peptide treatment alone induced significant and rapid anxiolytic and antidepressant-like effects in two tests for CUS-induced anhedonia-like reactivity and in the novelty-suppressed feeding test. Together these findings indicate a positive role for the D1-D2 heteromer in mediating depression- and anxiety-like behaviours and suggest its possible value as a novel therapeutic target. PMID:26431907
Energy Technology Data Exchange (ETDEWEB)
Zhang, Yingjie, E-mail: yzx@ansto.gov.au [Australian Nuclear Science and Technology Organization, Locked Bag 2001, Kirrawee DC, NSW 2232 (Australia); Bhadbhade, Mohan [Mark Wainwright Analytical Centre, University of New South Wales, Kensington, NSW 2052 (Australia); Karatchevtseva, Inna [Australian Nuclear Science and Technology Organization, Locked Bag 2001, Kirrawee DC, NSW 2232 (Australia); Price, Jason R. [Australian Synchrotron, 800 Blackburn Road, Clayton, VIC 3168 (Australia); Liu, Hao [Centre for Clean Energy Technology, School of Chemistry and Forensic Science, University of Technology Sydney, PO Box 123, Broadway, Sydney, NSW 2007 (Australia); Zhang, Zhaoming; Kong, Linggen [Australian Nuclear Science and Technology Organization, Locked Bag 2001, Kirrawee DC, NSW 2232 (Australia); Čejka, Jiří [Department of Mineralogy, National Museum, Václavské náměstí, 68, Prague 1, 115 79-CZ (Czech Republic); Lu, Kim; Lumpkin, Gregory R. [Australian Nuclear Science and Technology Organization, Locked Bag 2001, Kirrawee DC, NSW 2232 (Australia)
2015-03-15
Three new coordination polymers of uranium(VI) with pyromellitic acid (H{sub 4}btca) have been synthesized and structurally characterized. (ED)[(UO{sub 2})(btca)]·(DMSO)·3H{sub 2}O (1) (ED=ethylenediammonium; DMSO=dimethylsulfoxide) has a lamellar structure with intercalation of ED and DMSO. (NH{sub 4}){sub 2}[(UO{sub 2}){sub 6}O{sub 2}(OH){sub 6}(btca)]·~6H{sub 2}O (2) has a 3D framework built from 7-fold coordinated uranyl trinuclear units and btca ligands with 1D diamond-shaped channels (~8.5 Å×~8.6 Å). [(UO{sub 2}){sub 2}(H{sub 2}O)(btca)]·4H{sub 2}O (3) has a 3D network constructed by two types of 7-fold coordinated uranium polyhedron. The unique μ{sub 5}-coordination mode of btca in 3 enables the formation of 1D olive-shaped large channels (~4.5 Å×~19 Å). Vibrational modes, thermal stabilities and fluorescence properties have been investigated. - Graphical abstract: Table of content: three new uranium(VI) coordination polymers with pyromellitic acid (H{sub 4}btca) have been synthesized via room temperature and hydrothermal synthesis methods, and structurally characterized. Two to three dimensional (3D) frameworks are revealed. All 3D frameworks have unique 1D large channels. Their vibrational modes, thermal stabilities and photoluminescence properties have been investigated. - Highlights: • Three new coordination polymers of U(VI) with pyromellitic acid (H{sub 4}btca). • Structures from a 2D layer to 3D frameworks with unique 1D channels. • Unusual µ{sub 5}-(η{sub 1}:η{sub 2}:η{sub 1}:η{sub 2:}η{sub 1}) coordination mode of btca ligand. • Vibrational modes, thermal stabilities and luminescent properties reported.
Development of a new 1D urban canopy model: coherences between surface parameterizations
BLOND, Nadège; Mauree, Dasaraden; Kohler, Manon; Clappier, Alain
2015-01-01
A 1-D Canopy Interface Model (CIM) was developed in order to better simulate the effect of urban obstacles on the atmosphere in the boundary layer. The model solves the Navier-Stokes equations on a high-resolved gridded vertical column. The effect of the surface is simulated testing a set of theories and urban parameterizations. The final proposition guarantees its coherence with past theories in any atmospheric stability and terrain configuration. Obstacle characteristics are computed using...
A positron 1D-ACAR spectrometer for the study of 60Co containing materials
International Nuclear Information System (INIS)
In order to study some micro-structural changes in irradiated nuclear reactor-pressure vessel steels using a positron annihilation technique, a new three-detector set-up, suitable for a positron 1-dimensional angular correlation of annihilation radiation (1D-ACAR) study of 60Co-containing materials, was developed. The design of the equipment as well as results from test measurements are described. (orig.)
Scattering coefficients and gray-body factor for 1D BEC acoustic black holes: Exact results
Fabbri, Alessandro; Balbinot, Roberto; Anderson, Paul R.
2016-03-01
A complete set of exact analytic solutions to the mode equation is found in the region exterior to the acoustic horizon for a class of 1D Bose-Einstein condensate acoustic black holes. From these, analytic expressions for the scattering coefficients and gray-body factor are obtained. The results are used to verify previous predictions regarding the behaviors of the scattering coefficients and gray-body factor in the low-frequency limit.
Periodic Solutions of the 1D Vlasov-Maxwell System with Boundary Conditions
Bostan, Mihai
1998-01-01
We study the 1D Vlasov-Maxwell system with time periodic boundary conditions in its classical and relativistic form. For small data we prove existence of weak periodic solutions. It is necessary to impose non vanishing conditions for the incoming velocities in order to control the life-time of particles in the domain. In order to preserve the periodicity, another condition of vanishing the time average of the incoming current is imposed.
Equilibrium and Kinetics: Water Confined in Carbon Nanotube as 1D Lattice Gas
Zhou, Xin; Li, Cheng-Quan; Iwamoto, Mitsumasa
2002-01-01
A simple 1D lattice gas model is presented, which very well describes the equilibrium and kinetic behaviors of water confined in a thin carbon nanotube found in an atomistic molecular dynamics(MD) simulation {[} Nature {\\bf 414}, 188 (2001) {]}. The model parameters are corresponding to various physical interactions and can be calculated or estimated in statistic mechanics. The roles of every interaction in the water filling, emptying and transporting processes are clearly understood. Our res...
Numerical Simulation of Carbon Nanotubes/GaAs Hybrid PV Devices with AMPS-1D
Georgi Xosrovashvili; Gorji, Nima E.
2014-01-01
The performance and characteristics of a hybrid heterojunction single-walled carbon nanotube and GaAs solar cell are modelled and numerically simulated using AMPS-1D device simulation tool. The device physics and performance with different junction parameters are analysed. The results suggest that the open-circuit voltage changes very slightly by changing the electron affinity, acceptor and donor density while the other electrical parameters reach an optimum value. Increasing the concentratio...
Development of a hybrid deterministic/stochastic method for 1D nuclear reactor kinetics
International Nuclear Information System (INIS)
A new method has been implemented for solving the time-dependent neutron transport equation efficiently and accurately. This is accomplished by coupling the hybrid stochastic-deterministic steady-state coarse-mesh radiation transport (COMET) method [1,2] with the new predictor-corrector quasi-static method (PCQM) developed at Politecnico di Torino [3]. In this paper, the coupled method is implemented and tested in 1D slab geometry
Scattering coefficients and gray-body factor for 1D BEC acoustic black holes: exact results
Fabbri, Alessandro; Anderson, Paul R
2015-01-01
A complete set of exact analytic solutions to the mode equation are found in the region exterior to the acoustic horizon for a class of 1D Bose-Einstein condensate (BEC) acoustic black holes. From these, analytic expressions for the scattering coefficients and gray-body factor are obtained. The results are used to verify previous predictions regarding the behaviors of the scattering coefficients and gray-body factor in the low frequency limit.
Ultracold Bose Gases in 1D Disorder: From Lifshits Glass to Bose-Einstein Condensate
Lugan, Pierre; Clément, David; Bouyer, Philippe; Aspect, Alain; Lewenstein, Maciej; Sanchez-Palencia, Laurent
2007-01-01
We study an ultracold Bose gas in the presence of 1D disorder for repulsive inter-atomic interactions varying from zero to the Thomas-Fermi regime. We show that for weak interactions the Bose gas populates a finite number of localized single-particle Lifshits states, while for strong interactions a delocalized disordered Bose-Einstein condensate is formed. We discuss the schematic quantum-state diagram and derive the equations of state for various regimes.
Towards an Automatic Parking System using Bio-Inspired 1-D Optical Flow Sensors
Mafrica, Stefano; Servel, Alain; Ruffier, Franck
2015-01-01
Although several (semi-) automatic parking systems have been presented throughout the years [1]–[12], car manufacturers are still looking for low-cost sensors providing redundant information about the obstacles around the vehicle, as well as efficient methods of processing this information, in the hope of achieving a very high level of robustness. We therefore investigated how Local Motion Sensors (LMSs) [13], [14], comprising only of a few pixels giving 1-D optical flow (OF) measurements cou...
A new derivation of Akcasu's 'MLP' equations for 1-D particle transport in stochastic media
International Nuclear Information System (INIS)
This paper presents a new derivation of Akcasu's modified Levermore-Pomraning (MLP) model, which estimates the ensemble-averaged angular flux for particle transport problems in 1-D geometrically random media. The significant new feature of the MLP equations is that, unlike the earlier Levermore-Pomraning (LP) model, the MLP equations are exact for certain classes of problems with scattering. We also show, via asymptotic analyses, that the MLP equations are accurate in the atomic mix and diffusion limits
International Nuclear Information System (INIS)
The ''Generalized Riemann Problem'' (GRP) method is applied to 1-D compressible flows with material interfaces and variable cross section. The resulting scheme is second-order and used a ''mixed-type'' grid, where cell boundaries can be either Lagrangian or Eulerian. In fact, using the analytic resolution of discontinuities at cell boundaries, provided by the GRP solution, one can extend the scheme presented here to include any adaptive mesh
Axial transport solvers for the 2D/1D scheme in MPACT
International Nuclear Information System (INIS)
The MPACT code being developed collaboratively at the University of Michigan (UM) and Oak Ridge National Laboratory (ORNL) provides users with a variety of deterministic methods for solving the 2D and 3D Boltzmann transport equation. One of these methods, the 2D/1D technique, decomposes 3D problems into a 1D axial stack of 2D radial planes. In this scheme, the 2D planes are typically solved using a method such as the Method of Characteristics (MOC) to preserve the geometric heterogeneity in the radial direction. These planes are incorporated into a 1D axial solver, which can use a variety of methods. This work demonstrates the use of the traditional nodal methods for solving the 1D axial problem (finite difference, NEM, SANM, SP3), but also introduces a discrete ordinates (Sn) solver which uses up to cubic Legendre expansion spatially and can also incorporate higher order angular distributions of the radial transverse leakage. Several test cases are presented to demonstrate the accuracy of the solvers for various axial sizes. The first three are the 3D-C5G7 extension benchmark cases. The fourth case is a single quarter assembly benchmark problem with explicit nozzle, plenum, and core plate modelling known as AMA Problem 3. The final case is a quarter core benchmark problem that is an extension of the quarter assembly problem known as AMA Problem 5. In general, the diffusion-based axial solvers perform very well, though higher-order solvers provide some benefit in more difficult problems, particularly rodded cases. (author)
MNM1D: A Numerical Code for Colloid Transport in Porous Media: Implementation and Validation
Directory of Open Access Journals (Sweden)
Tiziana Tosco
2009-01-01
Full Text Available Problem statement: Understanding the mechanisms that control the transport and fate of colloidal particles in subsurface environments is a crucial issue faced by several researchers in the last years. In many cases, natural colloids have been shown to play a major role in the spreading of strongly sorbing contaminants, while manufactured micro-and nanoparticles, which are nowadays widely spread in the subsurface, can be toxic themselves. On the other hand, in recent years studies have been addressed to the use of highly reactive micro-and nanoparticle suspensions for the remediation of contaminated aquifers. Provide the set of partial-differential model equations and its numerical solution for the colloid transport under transient hydrochemical conditions, that have been previously shown to be extremely important in micro-and nanoparticle transport in porous media. Approach: This study presented a novel colloid transport model, called MNM1D (Micro-and Nanoparticle transport Model in porous media in 1D geometry, able to simulate the colloid behavior in porous media in the presence of both constant and transient hydrochemical parameters (namely ionic strength. The model accounts for attachment and detachment phenomena, that can be modeled with one or two linear and/or langmuirian interaction sites. The governing equations were solved using a finite-differences approach, herein presented and discussed in details. Results: Both qualitative and quantitative comparisons with results of well-established colloid transport models, based both on analytical and numerical solutions of the colloid transport equation, were performed. The MNM1D results were found to be in good agreement with these solutions. Conclusion: The shown good agreement between MNM1D and the other models indicated that this code can represent in the future a useful tool for the simulation of colloidal transport in groundwater under transient hydrochemical conditions.
5-HT(1B) and 5-HT(1D) receptors in the human trigeminal ganglion
DEFF Research Database (Denmark)
Hou, M; Kanje, M; Longmore, J; Tajti, J; Uddman, R; Edvinsson, L
5-Hydroxytryptamine (5-HT) is implicated in migraine and agonist directed against 5-HT(1B) and 5-HT(1D) receptors are commonly used as effective therapies. The antimigraine mechanisms involve the inhibition of intracranial sensory neuropeptide release. In order to determine which 5-HT(1) receptor...... expressed in the human trigeminal ganglion and they are mainly localized in medium-sized cells and they seem to colocalize with CGRP, SP and NOS....
Insulin stimulation regulates AS160 and TBC1D1 phosphorylation sites in human skeletal muscle
DEFF Research Database (Denmark)
Middelbeek, R J W; Chambers, M A; Tantiwong, P;
2013-01-01
Individuals with obesity and type 2 diabetes (T2D) are typically insulin resistant, exhibiting impaired skeletal muscle glucose uptake. Animal and cell culture experiments have shown that site-specific phosphorylation of the Rab-GTPase-activating proteins AS160 and TBC1D1 is critical for GLUT4 tr...... translocation facilitating glucose uptake, but their regulation in human skeletal muscle is not well understood....
A Fulling-Kuchment theorem for the 1D harmonic oscillator
Guillemin, Victor
2011-01-01
We prove that there exists a pair of "non-isospectral" 1D semiclassical Schr\\"odinger operators whose spectra agree modulo h^\\infty. In particular, all their semiclassical trace invariants are the same. Our proof is based on an idea of Fulling-Kuchment and Hadamard's variational formula applied to suitable perturbations of the harmonic oscillator. Keywords: Inverse spectral problems, semiclassical Schr\\"odinger operators, trace invariants, Hadamard's variational formula, harmonic oscillator, Penrose mushroom, Sturm-Liouville theory.
Prediction of car cabin environment by means of 1D and 3D cabin model
Jícha M.; Pokorný J.; Fišer J.
2012-01-01
Thermal comfort and also reduction of energy requirements of air-conditioning system in vehicle cabins are currently very intensively investigated and up-to-date issues. The article deals with two approaches of modelling of car cabin environment; the first model was created in simulation language Modelica (typical 1D approach without cabin geometry) and the second one was created in specialized software Theseus-FE (3D approach with cabin geometry). Performance and capabilities of this t...
From GPE to KPZ: finite temperature dynamical structure factor of the 1D Bose gas
Kulkarni, Manas; Lamacraft, Austen
2012-01-01
We study the finite temperature dynamical structure factor $S(k,\\omega)$ of a 1D Bose gas using numerical simulations of the Gross--Pitaevskii equation appropriate to a weakly interacting system. The lineshape of the phonon peaks in $S(k,\\omega)$ has a width $\\propto |k|^{3/2}$ at low wavevectors. This anomalous width arises from resonant three-phonon interactions, and reveals a remarkable connection to the Kardar--Parisi--Zhang universality class of dynamical critical phenomena.
INFIL1D: a quasi-analytical model for simulating one-dimensional, constant flux infiltration
International Nuclear Information System (INIS)
The program INFIL1D is designed to calculate approximate wetting-front advance into an unsaturated, uniformly moist, homogeneous soil profile, under constant surface-flux conditions. The code is based on a quasi-analytical method, which utilizes an assumed invariant functional relationship between reduced (normalized) flux and water content. The code uses general hydraulic property data in tabular form to simulate constant surface-flux infiltration. 10 references, 4 figures
Controlled Growth and Field-emission Application of 1D ZnS Nanostructures
Institute of Scientific and Technical Information of China (English)
X.S.Fang; Y.Bando; D.Golberg
2007-01-01
1 Results One-dimensional (1D) nanostructures have recently stimulated great interest due to their potential value for understanding fundamental physical concepts and for applications in constructing nanoscale electric and optoelectronic devices since the discovery of carbon nanotubes[1]. ZnS is one of the first semiconductors discovered and probably one of the most important materials in the electronics industry with a wide range of applications[2]. Controllable growth of nanostructures is a crucial is...
Stewart, Jonathan P.; Goulet, Christine A.; Bazzurro, Paolo; Claassen, Rebecca
2006-01-01
Results of 1D ground response analyses are typically not incorporated into probabilistic seismic hazard analyses (PSHA) in a statistically robust way. Often ground response is incorporated into PSHA using deterministic amplification factors. This simplistic method generates results that are intrinsically arbitrary and often unconservative. The main problem in probabilistically linking PSHA and ground response lies in quantifying the dispersion that is appropriate for use with ground respon...
A South American Prehistoric Mitogenome: Context, Continuity, and the Origin of Haplogroup C1d
Sans, Mónica; Figueiro, Gonzalo; Hughes, Cris E.; Lindo, John; Hidalgo, Pedro C.; Malhi, Ripan S.
2015-01-01
Based on mitochondrial DNA (mtDNA), it has been estimated that at least 15 founder haplogroups peopled the Americas. Subhaplogroup C1d3 was defined based on the mitogenome of a living individual from Uruguay that carried a lineage previously identified in hypervariable region I sequences from ancient and modern Uruguayan individuals. When complete mitogenomes were studied, additional substitutions were found in the coding region of the mitochondrial genome. Using a complete ancient mitogenome...
Influence of Underhood Flow on Engine Cooling Using 1-D And 3-D Approach
Bolehovský Ondřej; Novotný Jan
2015-01-01
This work deals with numerical simulation of complete cooling system of internal combustion engine (GT-SUITE), which also involves the simulation of flow in underhood using the computationally undemanding simulation. A detailed model of the internal combustion engine is extended to a cooling circuit model which is then coupled to a simplified underhood model which is created with the help of GT-COOL application as a 3-D model and afterwards transferred to a 1-D form. The approaches, one using...
High-Resolution Radiation Hybrid Map of Wheat Chromosome 1D
Kalavacharla, Venu; Hossain, Khwaja; Gu, Yong; Riera-Lizarazu, Oscar; Vales, M. Isabel; Bhamidimarri, Suresh; Gonzalez-Hernandez, Jose L.; Maan, Shivcharan S; Kianian, Shahryar F
2006-01-01
Physical mapping methods that do not rely on meiotic recombination are necessary for complex polyploid genomes such as wheat (Triticum aestivum L.). This need is due to the uneven distribution of recombination and significant variation in genetic to physical distance ratios. One method that has proven valuable in a number of nonplant and plant systems is radiation hybrid (RH) mapping. This work presents, for the first time, a high-resolution radiation hybrid map of wheat chromosome 1D (D geno...
International Nuclear Information System (INIS)
Three new coordination polymers of uranium(VI) with pyromellitic acid (H4btca) have been synthesized and structurally characterized. (ED)[(UO2)(btca)]·(DMSO)·3H2O (1) (ED=ethylenediammonium; DMSO=dimethylsulfoxide) has a lamellar structure with intercalation of ED and DMSO. (NH4)2[(UO2)6O2(OH)6(btca)]·~6H2O (2) has a 3D framework built from 7-fold coordinated uranyl trinuclear units and btca ligands with 1D diamond-shaped channels (~8.5 Å×~8.6 Å). [(UO2)2(H2O)(btca)]·4H2O (3) has a 3D network constructed by two types of 7-fold coordinated uranium polyhedron. The unique μ5-coordination mode of btca in 3 enables the formation of 1D olive-shaped large channels (~4.5 Å×~19 Å). Vibrational modes, thermal stabilities and fluorescence properties have been investigated. - Graphical abstract: Table of content: three new uranium(VI) coordination polymers with pyromellitic acid (H4btca) have been synthesized via room temperature and hydrothermal synthesis methods, and structurally characterized. Two to three dimensional (3D) frameworks are revealed. All 3D frameworks have unique 1D large channels. Their vibrational modes, thermal stabilities and photoluminescence properties have been investigated. - Highlights: • Three new coordination polymers of U(VI) with pyromellitic acid (H4btca). • Structures from a 2D layer to 3D frameworks with unique 1D channels. • Unusual µ5-(η1:η2:η1:η2:η1) coordination mode of btca ligand. • Vibrational modes, thermal stabilities and luminescent properties reported
Local source tomography for Vrancea (Romania) region: minimum 1D model
International Nuclear Information System (INIS)
The Vrancea zone is characterized by a narrow, vertical focal volume of intense and persistent seismicity in the depth range of 60-220 km. The processes associated with the Vrancea earthquakes outline a final stage of continental subduction with plate detachment, still far from being understood. Our main purpose is to perform local earthquake tomography to image crustal structures in Vrancea and adjacent regions as initial reference model in 3 D tomography. The study includes updating of the existing catalogues of seismic parameter data, calculation of a minimum 1D model and correlation with the existing controlled-source data. The model is determined by a trial-and-error process, with internal non-linear (iterative) inversion procedure (program VELEST). The average velocity model parameters are obtained by minimizing the standard deviations of the travel time residuals. The P-wave travel times for 500 well-locatable events are used, merging travel time data recorded by two separate independent seismic networks: the Romanian telemetered network (17 vertical-component S-13 seismometers) and the digital accelerometers network (30 three-component K2 instruments) installed in 1996 within the joint Romanian-German cooperation programme CRC 461. Since the two networks largely overlap geographically, we calculate a common minimum 1D model that guarantees a uniform location quality and uniform phase identification for the two networks. Absolute mislocation errors for the combined networks using the minimum 1D model are calculated using quarry blast data obtained during the VRANCEA99 refraction experiment deployed in 1999 in Romania as a contribution to the CRC 461 programme. The resulted minimum 1D model and station corrections are used to relocate all the considered events and to improve the consistency in the phase identification. The station corrections obtained are correlated with the lateral velocity variations in the surface geology of the region. This paper is a
Generation of nonclassical microwave states using an artificial atom in 1D open space
Hoi I.-C.; Palomaki T.; Lindkvist J.; Johansson G.; Delsing P.; Wilson C.M.
2012-01-01
We have embedded an artificial atom, a superconducting transmon qubit, in a 1D open space and investigated the scattering properties of an incident microwave coherent state. By studying the statistics of the reflected and transmitted fields, we demonstrate that the scattered states can be nonclassical. In particular, by measuring the second-order correlation function, $g^{(2)}$, we show photon antibunching in the reflected field and superbunching in the transmitted field. We also compare the ...
A study on cooling efficiency using 1-d analysis code suitable for cooling system of thermoforming
International Nuclear Information System (INIS)
Thermoforming is one of the most versatile and economical processes available for polymer products, but cycle time and production cost must be continuously reduced in order to improve the competitive power of products. In this study, water spray cooling was simulated to apply to a cooling system instead of compressed air cooling in order to shorten the cycle time and reduce the cost of compressed air used in the cooling process. At first, cooling time using compressed air was predicted in order to check the state of mass production. In the following step, the ratio of removed energy by air cooling or water spray cooling among the total removed energy was found by using 1-D analysis code of the cooling system under the condition of checking the possibility of conversion from 2-D to 1-D problem. The analysis results using water spray cooling show that cycle time can be reduced because of high cooling efficiency of water spray, and cost of production caused by using compressed air can be reduced by decreasing the amount of the used compressed air. The 1-D analysis code can be widely used in the design of a thermoforming cooling system, and parameters of the thermoforming process can be modified based on the recommended data suitable for a cooling system of thermoforming
Neutronic analysis of the 1D and 1E banks reflux detection system
International Nuclear Information System (INIS)
Two H Canyon neutron monitoring systems for early detection of postulated abnormal reflux conditions in the Second Uranium Cycle 1E and 1D Mixer-Settle Banks have been designed and built. Monte Carlo neutron transport simulations using the general purpose, general geometry, n-particle MCNP code have been performed to model expected response of the monitoring systems to varying conditions.The confirmatory studies documented herein conclude that the 1E and 1D neutron monitoring systems are able to achieve adequate neutron count rates for various neutron source and detector configurations, thereby eliminating excessive integration count time. Neutron count rate sensitivity studies are also performed. Conversely, the transport studies concluded that the neutron count rates are statistically insensitive to nitric acid content in the aqueous region and to the transition region length. These studies conclude that the 1E and 1D neutron monitoring systems are able to predict the postulated reflux conditions for all examined perturbations in the neutron source and detector configurations. In the cases examined, the relative change in the neutron count rates due to postulated transitions from normal 235U concentration levels to reflux levels remain satisfactory detectable
International Nuclear Information System (INIS)
The state of art of modelling activities related to integral experimental facilities of advanced passive reactors show to date important open items. The main advantage of using 1D plant codes is the capability of simulating the full interaction between components traditionally correctly modelled (condensers, heat exchangers, pipes and vessels) and other components for which codes are not 100% suitable (pools and containments). Polytechnical University of Catalonia (UPC) and Polytechnical University of Valencia (UPV) cooperated with other European research organizations in the 'Technology Enhancement for Passive Safety Systems' (TEPSS) project, within the European Fourth Framework Programme. It was a task of both Universities to supply analytical support of PANDA tests. The paper deals with the 1D/3D discussion in the framework of modelling activities related to integral passive facilities like PANDA. It starts choosing reference tests among those corresponding to our participation in TEPSS project. The discrepancies observed in a 1D simulation of the selected tests will be shown and analyzed. An evaluation of how the 3D version can lead to a better agreement with data will be included. Disadvantages of 3D codes will be shown too. Combining the use of different codes, and considering analyst criteria, will make possible to establish suitable recommendations from both engineering and scientific point of view. (author)
Avidity-dependent programming of autoreactive T cells in T1D.
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Ivana Durinovic-Belló
Full Text Available Fate determination for autoreactive T cells relies on a series of avidity-dependent interactions during T cell selection, represented by two general types of signals, one based on antigen expression and density during T cell development, and one based on genes that interpret the avidity of TCR interaction to guide developmental outcome. We used proinsulin-specific HLA class II tetramers to purify and determine transcriptional signatures for autoreactive T cells under differential selection in type 1 diabetes (T1D, in which insulin (INS genotypes consist of protective and susceptible alleles that regulate the level of proinsulin expression in the thymus. Upregulation of steroid nuclear receptor family 4A (NR4A and early growth response family genes in proinsulin-specific T cells was observed in individuals with susceptible INS-VNTR genotypes, suggesting a mechanism for avidity-dependent fate determination of the T cell repertoire in T1D. The NR4A genes act as translators of TCR signal strength that guide central and peripheral T cell fate decisions through transcriptional modification. We propose that maintenance of an NR4A-guided program in low avidity autoreactive T cells in T1D reflects their prior developmental experience influenced by proinsulin expression, identifying a pathway permissive for autoimmunity.
DYN1D-MSR dynamics code for molten salt reactors
International Nuclear Information System (INIS)
This paper reports about the DYN1D-MSR code development and dynamics studies of the molten salt reactors (MSR) - one of the 'Generation IV International Forum' concepts. In this forum the graphite-moderated channel type MSR based on the previous Oak Ridge National Laboratory research is considered. The liquid molten salt serves as a fuel and coolant, simultaneously and causes two physical peculiarities: the fission energy is released predominantly directly into the coolant and the delayed neutrons precursors are drifted by the fuel flow. The drift causes the spread of delayed neutrons distribution to the non-core parts of primary circuit and it can lead to a reactivity loss or gain in the case of fuel flow acceleration or deceleration, respectively. Therefore, specific 3D tool based on in house code DYN3D was developed in FZR. The code DYN3D-MSR is based on the solution of two-group neutron diffusion equation by the help of a nodal expansion method and it includes models of delayed neutrons drift and specific MSR heat release distribution. In this paper the development and verification of 1D version DYN1D-MSR of the code is described. The code has been validated with the experimental data gained from the molten salt reactor experiment performed in the Oak Ridge and after the validation it was applied to several typical transients (overcooling of fuel at the core inlet, reactivity insertion, and the fuel pump trip)
Quantitative 3D electromagnetic field determination of 1D nanostructures from single projection.
Energy Technology Data Exchange (ETDEWEB)
Phatak, C.; de Knoop, L.; Houdellier, F.; Gatel, C.; Hytch, M. J.; Masseboeuf, A.
2016-05-01
One-dimensional (1D) nanostructures have been regarded as the most promising building blocks for nanoelectronics and nanocomposite material systems as well as for alternative energy applications. Although they result in confinement of a material, their properties and interactions with other nanostructures are still very much three-dimensional (3D) in nature. In this work, we present a novel method for quantitative determination of the 3D electromagnetic fields in and around 1D nanostructures using a single electron wave phase image, thereby eliminating the cumbersome acquisition of tomographic data. Using symmetry arguments, we have reconstructed the 3D magnetic field of a nickel nanowire as well as the 3D electric field around a carbon nanotube field emitter, from one single projection. The accuracy of quantitative values determined here is shown to be a better fit to the physics at play than the value obtained by conventional analysis. Moreover the 3D reconstructions can then directly be visualized and used in the design of functional 3D architectures built using 1D nanostructures.
Quantitative 3D electromagnetic field determination of 1D nanostructures from single projection.
Phatak, C; de Knoop, L; Houdellier, F; Gatel, C; Hÿtch, M J; Masseboeuf, A
2016-05-01
One-dimensional (1D) nanostructures have been regarded as the most promising building blocks for nanoelectronics and nanocomposite material systems as well as for alternative energy applications. Although they result in confinement of a material, their properties and interactions with other nanostructures are still very much three-dimensional (3D) in nature. In this work, we present a novel method for quantitative determination of the 3D electromagnetic fields in and around 1D nanostructures using a single electron wave phase image, thereby eliminating the cumbersome acquisition of tomographic data. Using symmetry arguments, we have reconstructed the 3D magnetic field of a nickel nanowire as well as the 3D electric field around a carbon nanotube field emitter, from one single projection. The accuracy of quantitative values determined here is shown to be a better fit to the physics at play than the value obtained by conventional analysis. Moreover the 3D reconstructions can then directly be visualized and used in the design of functional 3D architectures built using 1D nanostructures. PMID:26998702
Surface defect inspection of TFT-LCD panels based on 1D Fourier method
Zhang, Teng-da; Lu, Rong-sheng
2016-01-01
Flat panel displays have been used in a wide range of electronic devices. The defects on their surfaces are an important factor affecting the product quality. Automated optical inspection (AOI) method is an important and effective means to perform the surface defection inspection. In this paper, a kind of defect extraction algorithm based on one dimensional (1D) Fourier theory for the surface defect extraction with periodic texture background is introduced. In the algorithm, the scanned surface images are firstly transformed from time domain to frequency domain by 1D Fourier transform. The periodic texture background on the surface is then removed by using filtering methods in the frequency domain. Then, a dual-threshold statistical control method is applied to separate the defects from the surface background. Traditional 1D Fourier transform scheme for detecting ordinary defects is very effective; however, the method is not where the defect direction is close to horizontal in periodic texture background. In order to tackle the problem, a mean threshold method based on faultless image is put forward. It firstly calculates the upper and lower control limits of the every reconstructed line scanned image with faultless and then computes the averages of the upper and lower limits. The averages then act as the constant double thresholds to extract the defects. The experimental results of different defects show that the method developed in the paper is very effective for TFT-LCD panel surface defect inspection even in the circumstance that the defect directions are close to horizontal.
Neutronic analysis of the 1D and 1E banks reflux detection system
Energy Technology Data Exchange (ETDEWEB)
Blanchard, A.
1999-12-21
Two H Canyon neutron monitoring systems for early detection of postulated abnormal reflux conditions in the Second Uranium Cycle 1E and 1D Mixer-Settle Banks have been designed and built. Monte Carlo neutron transport simulations using the general purpose, general geometry, n-particle MCNP code have been performed to model expected response of the monitoring systems to varying conditions.The confirmatory studies documented herein conclude that the 1E and 1D neutron monitoring systems are able to achieve adequate neutron count rates for various neutron source and detector configurations, thereby eliminating excessive integration count time. Neutron count rate sensitivity studies are also performed. Conversely, the transport studies concluded that the neutron count rates are statistically insensitive to nitric acid content in the aqueous region and to the transition region length. These studies conclude that the 1E and 1D neutron monitoring systems are able to predict the postulated reflux conditions for all examined perturbations in the neutron source and detector configurations. In the cases examined, the relative change in the neutron count rates due to postulated transitions from normal {sup 235}U concentration levels to reflux levels remain satisfactory detectable.
Influence of Underhood Flow on Engine Cooling Using 1-D And 3-D Approach
Directory of Open Access Journals (Sweden)
Bolehovský Ondřej
2015-12-01
Full Text Available This work deals with numerical simulation of complete cooling system of internal combustion engine (GT-SUITE, which also involves the simulation of flow in underhood using the computationally undemanding simulation. A detailed model of the internal combustion engine is extended to a cooling circuit model which is then coupled to a simplified underhood model which is created with the help of GT-COOL application as a 3-D model and afterwards transferred to a 1-D form. The approaches, one using 1-D solution of arrangement of the heat exchangers and the other 3-D approach using the underhood model, were investigated in two steady states corresponding to various vehicle speeds and engine load. These simulations have shown the inappropriateness of 1-D approach when solving the flow in the heat exchangers in the underhood and helped to explore a relatively undemanding method of flow simulation in the underhood, which enables to detect the interaction between the models of the cooling system and the internal combustion engine and the issue of arrangement of the heat exchangers in the underhood.
Yadav, Munendra; Bhunia, Asamanjoy; Jana, Salil K; Roesky, Peter W
2016-03-21
The chiral 1D-coordination polymers (CP) {[Ln2(MnLCl)2(NO3)2(dmf)6(H2O)2]·xH2O}n [Ln = Pr (1), Nd (2), Sm (3), and Gd (4)] were synthesized by the reaction of N,N'-bis(4-carboxysalicylidene)cyclohexanediamine (H4L) with [MnCl2·4(H2O)] and [Ln(NO3)3·x(H2O)] in the presence of dmf/pyridine at 90 °C. The polymers consist of manganese-salen-based moieties having carboxylate linkers connected to rare earth atoms in a 1D-chain structure. The polymers are very easily accessible. A one-step synthesis for the ligand and a second step for the preparation of the 1D coordination polymers starting from commercially available material are needed. The solid state structures of 1-4 were established by single-crystal X-ray diffraction. Compounds 1-4 were investigated as heterogeneous catalysts for the sulfoxidation reaction of various alkyl and aryl sulfides. The influence of various solvents and oxidizing agents on the catalytic reaction was examined. It was found that the catalysts were active for more than one reaction cycle without significant loss of activity. For phenylsulfide with 1 mol % of the catalyst 4, a maximum conversion 100% and a chemoselectivity 88% were observed. PMID:26923559
Effects of curcumin on synapses in APPswe/PS1dE9 mice.
He, Yingkun; Wang, Pengwen; Wei, Peng; Feng, Huili; Ren, Ying; Yang, Jinduo; Rao, Yingxue; Shi, Jing; Tian, Jinzhou
2016-06-01
Significant losses of synapses have been demonstrated in studies of Alzheimer's disease (AD), but structural and functional changes in synapses that depend on alterations of the postsynaptic density (PSD) area occur prior to synaptic loss and play a crucial role in the pathology of AD. Evidence suggests that curcumin can ameliorate the learning and memory deficits of AD. To investigate the effects of curcumin on synapses, APPswe/PS1dE9 double transgenic mice (an AD model) were used, and the ultra-structures of synapses and synapse-associated proteins were observed. Six months after administration, few abnormal synapses were observed upon electron microscopy in the hippocampal CA1 areas of the APPswe/PS1dE9 double transgenic mice. The treatment of the mice with curcumin resulted in improvements in the quantity and structure of the synapses. Immunohistochemistry and western blot analyses revealed that the expressions of PSD95 and Shank1 were reduced in the hippocampal CA1 areas of the APPswe/PS1dE9 double transgenic mice, but curcumin treatment increased the expressions of these proteins. Our findings suggest that curcumin improved the structure and function of the synapses by regulating the synapse-related proteins PSD95 and Shank1. PMID:26957323
Numerical simulation of Ge solar cells using D-AMPS-1D code
International Nuclear Information System (INIS)
A solar cell is a solid state device that converts the energy of sunlight directly into electricity by the photovoltaic effect. When light with photon energies greater than the band gap is absorbed by a semiconductor material, free electrons and free holes are generated by optical excitation in the material. The main characteristic of a photovoltaic device is the presence of internal electric field able to separate the free electrons and holes so they can pass out of the material to the external circuit before they recombine. Numerical simulation of photovoltaic devices plays a crucial role in their design, performance prediction, and comprehension of the fundamental phenomena ruling their operation. The electrical transport and the optical behavior of the solar cells discussed in this work were studied with the simulation code D-AMPS-1D. This software is an updated version of the one-dimensional (1D) simulation program Analysis of Microelectronic and Photonic Devices (AMPS) that was initially developed at The Penn State University, USA. Structures such as homojunctions, heterojunctions, multijunctions, etc., resulting from stacking layers of different materials can be studied by appropriately selecting characteristic parameters. In this work, examples of cells simulation made with D-AMPS-1D are shown. Particularly, results of Ge photovoltaic devices are presented. The role of the InGaP buffer on the device was studied. Moreover, a comparison of the simulated electrical parameters with experimental results was performed.
Numerical simulation of Ge solar cells using D-AMPS-1D code
Energy Technology Data Exchange (ETDEWEB)
Barrera, Marcela, E-mail: barrera@tandar.cnea.gov.ar [Comision Nacional de Energia Atomica, Avenida General Paz 1499, San Martin 1650, Buenos Aires (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET) (Argentina); Rubinelli, Francisco [Instituto de Desarrollo Tecnologico para la Industria Quimica (INTEC)-CONICET, Gueemes 3450, Santa Fe 3000 (Argentina); Rey-Stolle, Ignacio [Instituto de Energia Solar, Universidad Politecnica de Madrid, Avenida Complutense 30, Madrid 28040 (Spain); Pla, Juan [Comision Nacional de Energia Atomica, Avenida General Paz 1499, San Martin 1650, Buenos Aires (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET) (Argentina)
2012-08-15
A solar cell is a solid state device that converts the energy of sunlight directly into electricity by the photovoltaic effect. When light with photon energies greater than the band gap is absorbed by a semiconductor material, free electrons and free holes are generated by optical excitation in the material. The main characteristic of a photovoltaic device is the presence of internal electric field able to separate the free electrons and holes so they can pass out of the material to the external circuit before they recombine. Numerical simulation of photovoltaic devices plays a crucial role in their design, performance prediction, and comprehension of the fundamental phenomena ruling their operation. The electrical transport and the optical behavior of the solar cells discussed in this work were studied with the simulation code D-AMPS-1D. This software is an updated version of the one-dimensional (1D) simulation program Analysis of Microelectronic and Photonic Devices (AMPS) that was initially developed at The Penn State University, USA. Structures such as homojunctions, heterojunctions, multijunctions, etc., resulting from stacking layers of different materials can be studied by appropriately selecting characteristic parameters. In this work, examples of cells simulation made with D-AMPS-1D are shown. Particularly, results of Ge photovoltaic devices are presented. The role of the InGaP buffer on the device was studied. Moreover, a comparison of the simulated electrical parameters with experimental results was performed.
Study of 1D stranged-charm meson family using HQET
Gupta, Pallavi
2015-01-01
Recently LHCb predicted spin 1 and spin 3 states D* s1(2860) and D* s3(2860) which are studied through their strong decays, and are assigned to fit the 13D1and 13D3 states in the charm spectroscopy. In this paper,using the heavy quark effective theory, we state that assigning D*s1(2860) as the mixing of 13D1 - 23S1 states, is rather a better justification to its observed experimental values than a pure state. We study its decay modes variation with hadronic coupling constant gxh and the mixing angle . We appoint spin 3 state D* s3(2860) as the missing 1D 3- JP state, and also study its decay channel behavior with coupling constant gyh. To appreciate the above results, we check the variation of decay modes for their spin partners states i.e. 1D2 and 1D'2 with their masses and strong coupling constant i.e. gxh and gyh. Our calculation using HQET approach give mixing angle between the 13D1 - 23S1 state for D* s1(2860) to lie in the range (-1.6 radians < theta < -1.2 radians). Our calculation for coupling c...
Recessive TBC1D24 Mutations Are Frequent in Moroccan Non-Syndromic Hearing Loss Pedigrees.
Directory of Open Access Journals (Sweden)
Amina Bakhchane
Full Text Available Mutations in the TBC1D24 gene are responsible for four neurological presentations: infantile epileptic encephalopathy, infantile myoclonic epilepsy, DOORS (deafness, onychodystrophy, osteodystrophy, mental retardation and seizures and NSHL (non-syndromic hearing loss. For the latter, two recessive (DFNB86 and one dominant (DFNA65 mutations have so far been identified in consanguineous Pakistani and European/Chinese families, respectively. Here we report the results of a genetic study performed on a large Moroccan cohort of deaf patients that identified three families with compound heterozygote mutations in TBC1D24. Four novel mutations were identified, among which, one c.641G>A (p.Arg214His was present in the three families, and has a frequency of 2% in control Moroccan population with normal hearing, suggesting that it acts as an hypomorphic variant leading to restricted deafness when combined with another recessive severe mutation. Altogether, our results show that mutations in TBC1D24 gene are a frequent cause (>2% of NSHL in Morocco, and that due to its possible compound heterozygote recessive transmission, this gene should be further considered and screened in other deaf cohorts.
Wen, Kechun; He, Weidong
2015-09-01
One-dimensional (1D) nanocrystals, such as nanorods and nanowires, have received extensive attention in the nanomaterials field due to their large surface areas and 1D confined transport properties. Oriented attachment (OA) is now recognized as a major growth mechanism for efficiently synthesizing 1D nanocrystals. Recently, atomic layer deposition (ALD) has been modified to be a powerful vapor-phase technique with which to synthesize 1D OA nanorods/nanowires with high efficiency and quality by increasing the temperature and purging time. In this invited mini-review, we look into the advantages of OA and high-temperature ALD, and investigate the potential of employing the OA growth mechanism for the synthesis of 1D nanocrystals via modified ALD, aiming to provide guidance to researchers in the fields of both OA and ALD for efficient synthesis of 1D nanocrystals.
Directory of Open Access Journals (Sweden)
Xueying Zhao
2014-01-01
Full Text Available Alpha1D-adrenergic receptor (α1D-AR plays important roles in regulating physiological and pathological responses mediated by catecholamines, particularly in the cardiovascular and urinary systems. The present study was designed to investigate the expression profile of α1D-AR in the diabetic kidneys and its modulation by activation of peroxisome proliferator-activated receptors (PPARs. 12-week-old Zucker lean (ZL and Zucker diabetic fatty (ZD rats were treated with fenofibrate or rosiglitazone for 8–10 weeks. Gene microarray, real-time PCR, and confocal immunofluorescence microscopy were performed to assess mRNA and protein expression of α1D-AR in rat kidney tissue. Using microarray, we found that α1D-AR gene was dramatically upregulated in 22-week-old ZD rats compared to ZL controls. Quantitative PCR analysis verified a 16-fold increase in α1D-AR mRNA in renal cortex from ZD animals compared to normal controls. Chronic treatment with fenofibrate or rosiglitazone reduced renal cortical α1D-AR gene. Immunofluorescence staining confirmed that α1D-AR protein was induced in the glomeruli and tubules of diabetic rats. Moreover, dual immunostaining for α1D-AR and kidney injury molecule-1 indicated that α1D-AR was expressed in dedifferentiated proximal tubules of diabetic Zucker rats. Taken together, our results show that α1D-AR expression is upregulated in the diabetic kidneys. PPAR activation suppressed renal expression of α1D-AR in diabetic nephropathy.
Position error in profiles retrieved from MIPAS observations with a 1-D algorithm
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M. Carlotti
2012-09-01
Full Text Available The information load (IL analysis, first introduced for the two-dimensional approach (Carlotti and Magnani, 2009, is applied to the inversion of MIPAS observations operated with a 1-dimensional (1-D retrieval algorithm. The IL distribution of MIPAS spectra is shown to be often asymmetrical with respect to the tangent points of the observations and permits to identify the preferential latitude where the profiles retrieved with a 1-D algorithm should be geo-located. Therefore a position error is made when the tangent points of the observations are used to assign the geo-location of the retrieved profile. We assess the amplitude of the position error for some of the MIPAS main targets and we show that the IL analysis can also be used as a tool for the selection of observations that, when analyzed, minimize the position error of the retrieved profile. When the temperature (T profiles are used for the retrieval of volume mixing ratio (VMR of atmospheric constituents, the T position error (of the order of 1.5 degrees of latitude induces a VMR error that is directly connected with the horizontal T gradients. Temperature profiles can be externally-provided or determined in a previous step of the retrieval process. In the first case, the IL analysis shows that a meaningful fraction (often exceeding 50% of the VMR error deriving from the 1-D approximation is to be attributed to the mismatch between the position assigned to the external T profile and the positions where T is required by the analyzed observations. In the second case the retrieved T values suffer by an error of 1.5–2 K due to neglecting the horizontal variability of T; however the error induced on VMRs is of minor entity because of the generally small mismatch between the IL distribution of the observations analyzed to retrieve T and those analyzed to retrieve the VMR target. An estimate of the contribution of the
Hydrothermally processed 1D hydroxyapatite: Mechanism of formation and biocompatibility studies.
Stojanović, Zoran S; Ignjatović, Nenad; Wu, Victoria; Žunič, Vojka; Veselinović, Ljiljana; Škapin, Srečo; Miljković, Miroslav; Uskoković, Vuk; Uskoković, Dragan
2016-11-01
Recent developments in bone tissue engineering have led to an increased interest in one-dimensional (1D) hydroxyapatite (HA) nano- and micro-structures such as wires, ribbons and tubes. They have been proposed for use as cell substrates, reinforcing phases in composites and carriers for biologically active substances. Here we demonstrate the synthesis of 1D HA structures using an optimized, urea-assisted, high-yield hydrothermal batch process. The one-pot process, yielding HA structures composed of bundles of ribbons and wires, was typified by the simultaneous occurrence of a multitude of intermediate reactions, failing to meet the uniformity criteria over particle morphology and size. To overcome these issues, the preparation procedure was divided to two stages: dicalcium phosphate platelets synthesized in the first step were used as a precursor for the synthesis of 1D HA in the second stage. Despite the elongated particle morphologies, both the precursor and the final product exhibited excellent biocompatibility and caused no reduction of viability when tested against osteoblastic MC3T3-E1 cells in 2D culture up to the concentration of 2.6mg/cm(2). X-ray powder diffraction combined with a range of electron microscopies and laser diffraction analyses was used to elucidate the formation mechanism and the microstructure of the final particles. The two-step synthesis involved a more direct transformation of DCP to 1D HA with the average diameter of 37nm and the aspect ratio exceeding 100:1. The comparison of crystalline domain sizes along different crystallographic directions showed no signs of significant anisotropy, while indicating that individual nanowires are ordered in bundles in the b crystallographic direction of the P63/m space group of HA. Intermediate processes, e.g., dehydration of dicalcium phosphate, are critical for the formation of 1D HA alongside other key aspects of this phase transformation, it must be investigated in more detail in the continuous
Kuznetsova, Elena; Sadeghpour, H R; Yelin, Susanne F
2016-01-01
We analyze in detail the possibility to use charge-dipole interaction between a single polar molecule or a 1D molecular array and a single Rydberg atom to read out rotational populations. The change in the Rydberg electron energy is conditioned on the rotational state of the polar molecules, allowing for realization of a CNOT quantum gate between the molecules and the atom. Subsequent readout of the atomic fluorescence results in a non-destructive measurement of the rotational state. We study the interaction between a 1D array of polar molecules and an array or a cloud of atoms in a Rydberg superatom (blockaded) state and calculate the resolved energy shifts of Rb(60s) with KRb and RbYb molecules, with N=1, 3, 5 molecules. We show that collective molecular rotational states can be read out using the conditioned Rydberg energy shifts.
Upgrade of 2-D antenna array for microwave imaging reflectometry and ECE imaging
International Nuclear Information System (INIS)
Two types of 2-D Microwave Imaging, Microwave Imaging Reflectometry (MIR) and Electron Cyclotron Emission Imaging (ECEI) have been developed for the Large Helical Device (LHD). These are methods of 2-D / 3-D imaging diagnostics on electron density fluctuations and electron temperature for the investigation of micro-turbulence and magneto-hydrodynamic instabilities in magnetically confined plasmas. 1-D horn antenna array was developed for a 2-D receiver antenna array of the MIR (freq. range: 50 - 75 GHz). This antenna is also able to be used for a receiver of the ECEI (freq. range: 95 - 110 GHz). To apply the ECEI receiver, and to extend the measurement range of these diagnostics, the 1-D horn antenna array was upgraded. (author)
Energy Technology Data Exchange (ETDEWEB)
Ostlund, N.S.
1980-01-01
The field of attached scientific processors (''array processors'') is surveyed, and an attempt is made to indicate their present and possible future use in computational chemistry. The current commercial products from Floating Point Systems, Inc., Datawest Corporation, and CSP, Inc. are discussed.
DEFF Research Database (Denmark)
Falster, Peter; Jenkins, Michael
1999-01-01
This report is the result of collaboration between the authors during the first 8 months of 1999 when M. Jenkins was visiting professor at DTU. The report documents the development of a tool for the investigation of array theory concepts and in particular presents various approaches to choose...
International Nuclear Information System (INIS)
A detector array and method are described in which sets of electrode elements are provided. Each set consists of a number of linear extending parallel electrodes. The sets of electrode elements are disposed at an angle (preferably orthogonal) with respect to one another so that the individual elements intersect and overlap individual elements of the other sets. Electrical insulation is provided between the overlapping elements. The detector array is exposed to a source of charged particles which in accordance with one embodiment comprise electrons derived from a microchannel array plate exposed to photons. Amplifier and discriminator means are provided for each individual electrode element. Detection means are provided to sense pulses on individual electrode elements in the sets, with coincidence of pulses on individual intersecting electrode elements being indicative of charged particle impact at the intersection of the elements. Electronic readout means provide an indication of coincident events and the location where the charged particle or particles impacted. Display means are provided for generating appropriate displays representative of the intensity and locaton of charged particles impacting on the detector array
Mitchell, Daniel A.; Greenhill, Lincoln J.; Ord, Stephen M.; Bernardi, Gianni
2010-01-01
It is shown that the excellent Murchison Radio-astronomy Observatory site allows the Murchison Widefield Array to employ a simple RFI blanking scheme and still calibrate visibilities and form images in the FM radio band. The techniques described are running autonomously in our calibration and imagin
Directory of Open Access Journals (Sweden)
Hans Peter Lang
2005-04-01
Full Text Available Miniaturized microfabricated sensors have enormous potential in gas detection, biochemical analysis, medical applications, quality and process control, and product authenticity issues. Here, we highlight an ultrasensitive mechanical way of converting (bio-chemical or physical processes into a recordable signal using microfabricated cantilever arrays.
Jiang, Guanghuai; Xiang, Yanghai; Zhao, Jiying; Yin, Dedong; Zhao, Xianfeng; Zhu, Lihuang; Zhai, Wenxue
2014-01-01
Panicle type has a direct bearing on rice yield. Here, we characterized a rice clustered-spikelet mutant, sped1-D, with shortened pedicels and/or secondary branches, which exhibits decreased pollen fertility. We cloned sped1-D and found that it encodes a pentatricopeptide repeat protein. We investigated the global expression profiles of wild-type, 9311, and sped1-D plants using Illumina RNA sequencing. The expression of several GID1L2 family members was downregulated in the sped1-D mutant, su...
Computational Study and Analysis of Structural Imperfections in 1D and 2D Photonic Crystals
Energy Technology Data Exchange (ETDEWEB)
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
Arroyo-Torres, B; Chiavassa, A; Scholz, M; Freytag, B; Marcaide, J M; Hauschildt, P H; Wood, P R; Abellan, F J
2015-01-01
We present the atmospheric structure and the fundamental parameters of three red supergiants, increasing the sample of RSGs observed by near-infrared spectro-interferometry. Additionally, we test possible mechanisms that may explain the large observed atmospheric extensions of RSGs. We carried out spectro-interferometric observations of 3 RSGs in the near-infrared K-band with the VLTI/AMBER instrument at medium spectral resolution. To comprehend the extended atmospheres, we compared our observational results to predictions by available hydrostatic PHOENIX, available 3-D convection, and new 1-D self-excited pulsation models of RSGs. Our near-infrared flux spectra are well reproduced by the PHOENIX model atmospheres. The continuum visibility values are consistent with a limb-darkened disk as predicted by the PHOENIX models, allowing us to determine the angular diameter and the fundamental parameters of our sources. Nonetheless, in the case of V602 Car and HD 95686, the PHOENIX model visibilities do not predict ...
Shrama, Satinder K; Saurakhiya, Neelam; Barthwal, Sumit; Kumar, Rudra; Sharma, Ashutosh
2014-01-01
One-dimensional (1-D) ultrathin (15 nm) and thin (100 nm) aligned 1-D (0001) and ( 000 1 ¯ ) oriented zinc oxide (ZnO) nanowire (NW) arrays were fabricated on copper substrates by one-step electrochemical deposition inside the pores of polycarbonate membranes. The aspect ratio dependence of the compressive stress because of the lattice mismatch between NW array/substrate interface and crystallite size variations is investigated. X-ray diffraction results show that the polycrystalline ZnO NWs ...
InP nanopore arrays for photoelectrochemical hydrogen generation
Li, Qiang; Zheng, Maojun; Zhang, Bin; Zhu, Changqing; Wang, Faze; Song, Jingnan; Zhong, Miao; Ma, Li; Shen, Wenzhong
2016-02-01
We report a facile and large-scale fabrication of highly ordered one-dimensional (1D) indium phosphide (InP) nanopore arrays (NPs) and their application as photoelectrodes for photoelectrochemical (PEC) hydrogen production. These InP NPs exhibit superior PEC performance due to their excellent light-trapping characteristics, high-quality 1D conducting channels and large surface areas. The photocurrent density of optimized InP NPs is 8.9 times higher than that of planar counterpart at an applied potential of +0.3 V versus RHE under AM 1.5G illumination (100 mW cm-2). In addition, the onset potential of InP NPs exhibits 105 mV of cathodic shift relative to planar control. The superior performance of the nanoporous samples is further explained by Mott-Schottky and electrochemical impedance spectroscopy ananlysis.
Energy Technology Data Exchange (ETDEWEB)
Heidelberger, Philip; Steinmacher-Burow, Burkhard
2015-01-06
According to one embodiment, a method for implementing an array-based queue in memory of a memory system that includes a controller includes configuring, in the memory, metadata of the array-based queue. The configuring comprises defining, in metadata, an array start location in the memory for the array-based queue, defining, in the metadata, an array size for the array-based queue, defining, in the metadata, a queue top for the array-based queue and defining, in the metadata, a queue bottom for the array-based queue. The method also includes the controller serving a request for an operation on the queue, the request providing the location in the memory of the metadata of the queue.
Nested 1D-2D approach for urban surface flood modeling
Murla, Damian; Willems, Patrick
2015-04-01
Floods in urban areas as a consequence of sewer capacity exceedance receive increased attention because of trends in urbanization (increased population density and impermeability of the surface) and climate change. Despite the strong recent developments in numerical modeling of water systems, urban surface flood modeling is still a major challenge. Whereas very advanced and accurate flood modeling systems are in place and operation by many river authorities in support of flood management along rivers, this is not yet the case in urban water management. Reasons include the small scale of the urban inundation processes, the need to have very high resolution topographical information available, and the huge computational demands. Urban drainage related inundation modeling requires a 1D full hydrodynamic model of the sewer network to be coupled with a 2D surface flood model. To reduce the computational times, 0D (flood cones), 1D/quasi-2D surface flood modeling approaches have been developed and applied in some case studies. In this research, a nested 1D/2D hydraulic model has been developed for an urban catchment at the city of Gent (Belgium), linking the underground sewer (minor system) with the overland surface (major system). For the overland surface flood modelling, comparison was made of 0D, 1D/quasi-2D and full 2D approaches. The approaches are advanced by considering nested 1D-2D approaches, including infiltration in the green city areas, and allowing the effects of surface storm water storage to be simulated. An optimal nested combination of three different mesh resolutions was identified; based on a compromise between precision and simulation time for further real-time flood forecasting, warning and control applications. Main streets as mesh zones together with buildings as void regions constitute one of these mesh resolution (3.75m2 - 15m2); they have been included since they channel most of the flood water from the manholes and they improve the accuracy of
Radar techniques using array antennas
Wirth, Wulf-Dieter
2013-01-01
Radar Techniques Using Array Antennas is a thorough introduction to the possibilities of radar technology based on electronic steerable and active array antennas. Topics covered include array signal processing, array calibration, adaptive digital beamforming, adaptive monopulse, superresolution, pulse compression, sequential detection, target detection with long pulse series, space-time adaptive processing (STAP), moving target detection using synthetic aperture radar (SAR), target imaging, energy management and system parameter relations. The discussed methods are confirmed by simulation stud
Kim, Wun-gwi
2013-12-01
Membranes utilizing nanoporous one-dimensional (1D) and two-dimensional (2D) materials are emerging as attractive candidates for applications in molecular separations and related areas. Such nanotubular and nanolayered materials include carbon nanotubes, metal oxide nanotubes, layered zeolites, porous layered oxides, layered aluminophosphates, and porous graphenes. By virtue of their unique shape, size, and structure, they possess transport properties that are advantageous for membrane and thin film applications. These materials also have very different chemistry from more conventional porous 3D materials, due to the existence of a large, chemically active, external surface area. This feature also necessitates the development of innovative strategies to process these materials into membranes and thin films with high performance. This work provides the first comprehensive review of this emerging area. We first discuss approaches for the synthesis and structural characterization of nanoporous 1D and 2D materials. Thereafter, we elucidate different approaches for fabrication of membranes and thin films from these materials, either as multiphase (composite/hybrid) or single-phase membranes. The influence of surface chemistry and processing techniques on the membrane morphology is highlighted. We then discuss the applications of such membranes in areas relating to molecular transport and separation, e.g. gas and liquid-phase separations, water purification, and ion-conducting membranes. The review concludes with a discussion of the present outlook and some of the key scientific challenges to be addressed on the path to industrially applicable membranes containing nanoporous 1D and 2D materials. © 2013 Elsevier Ltd.
1-D and 2-D electrophoresis protein profiles of the scorpion venom from Brotheas amazonicus
Energy Technology Data Exchange (ETDEWEB)
Higa, A.M.; Noronha, M.D.N. [Universidade do Estado do Amazonas (UEA), Manaus, AM (Brazil). Rede Proteomica do Amazonas (Proteam). Lab. de Genomica e Proteomica; Rocha-Oliveira, F.; Lopez-Lozano, J.L.L. [Universidade Federal do Amazonas (UFAM), Manaus, AM (Brazil). Pos-Graduacao em Biotecnologia
2008-07-01
Full text: Introduction: Scorpions venoms show specific neurotoxins to insect or mammals. These toxins are very important molecular tools to development of news drugs or bioinsecticides. Brotheas amazonicus scorpion is an endemic specie in Amazonian Rain Forest, but your venom do not show toxicity in humans. Information about biological specific activity on insect of this venom is not known yet. Objectives: Molecular protein toxins profiles of the venom from Brotheas amazonicus scorpion by 1-D and 2-D electrophoresis methods to detected toxins with potential biotech applications. Results: Several spots 'families' with {approx} 60, 70 and 80 kDa were detected in gel acidic region with pI {approx} 4,5 - 6 range, in the same region 1-D zimography showed proteolytic activity on gelatin and fibrinogen and proteolytic activity was inhibited by PMSF, suggesting scorpion serine proteinases. 50 kDa proteins were detected with pI {approx} 6,5 - 7 range. In 23 - 50 kDa gel acid region were observed some proteins. In 23 - 14 kDa gel acidic region were detected proteins with pI 4 - 7 range. 1-D Tris-tricine gel showed proteins with {approx} 7 kDa, suggesting scorpion neurotoxins. In gel basic region only 14 kDa proteins were observed with pI {approx} 9 - 10 range. Conclusion: Molecular profile of the scorpion venom from B. amazonicus showed proteins with high and low molecular masses, mainly with acidic pI. Proteolytic activity suggest serine proteinases with high molecular masses and 7 kDa proteins in B. amazonicus venom suggest scorpion neurotoxins. Purification and molecular characterization of these toxins are in course.
NMR 1D-imaging of water infiltration into meso-porous matrices
International Nuclear Information System (INIS)
It is shown that coupling nuclear magnetic resonance (NMR) 1D-imaging with the measure of NMR relaxation times and self-diffusion coefficients can be a very powerful approach to investigate fluid infiltration into porous media. Such an experimental design was used to study the very slow seeping of pure water into hydrophobic materials. We consider here three model samples of nuclear waste conditioning matrices which consist in a dispersion of NaNO3 (highly soluble) and/or BaSO4 (poorly soluble) salt grains embedded in a bitumen matrix. Beyond studying the moisture progression according to the sample depth, we analyze the water NMR relaxation times and self-diffusion coefficients along its 1D-concentration profile to obtain spatially resolved information on the solution properties and on the porous structure at different scales. It is also shown that, when the relaxation or self-diffusion properties are multimodal, the 1D-profile of each water population is recovered. Three main levels of information were disclosed along the depth-profiles. They concern (i) the water uptake kinetics, (ii) the salinity and the molecular dynamics of the infiltrated solutions and (iii) the microstructure of the water-filled porosities: open networks coexisting with closed pores. All these findings were fully validated and enriched by NMR cryo-poro-metry experiments and by performing environmental scanning electronic microscopy observations. Surprisingly, results clearly show that insoluble salts enhance the water progression and thereby increase the capability of the material to uptake water. (authors)
1-D and 2-D electrophoresis protein profiles of the scorpion venom from Brotheas amazonicus
International Nuclear Information System (INIS)
Full text: Introduction: Scorpions venoms show specific neurotoxins to insect or mammals. These toxins are very important molecular tools to development of news drugs or bioinsecticides. Brotheas amazonicus scorpion is an endemic specie in Amazonian Rain Forest, but your venom do not show toxicity in humans. Information about biological specific activity on insect of this venom is not known yet. Objectives: Molecular protein toxins profiles of the venom from Brotheas amazonicus scorpion by 1-D and 2-D electrophoresis methods to detected toxins with potential biotech applications. Results: Several spots 'families' with ∼ 60, 70 and 80 kDa were detected in gel acidic region with pI ∼ 4,5 - 6 range, in the same region 1-D zimography showed proteolytic activity on gelatin and fibrinogen and proteolytic activity was inhibited by PMSF, suggesting scorpion serine proteinases. 50 kDa proteins were detected with pI ∼ 6,5 - 7 range. In 23 - 50 kDa gel acid region were observed some proteins. In 23 - 14 kDa gel acidic region were detected proteins with pI 4 - 7 range. 1-D Tris-tricine gel showed proteins with ∼ 7 kDa, suggesting scorpion neurotoxins. In gel basic region only 14 kDa proteins were observed with pI ∼ 9 - 10 range. Conclusion: Molecular profile of the scorpion venom from B. amazonicus showed proteins with high and low molecular masses, mainly with acidic pI. Proteolytic activity suggest serine proteinases with high molecular masses and 7 kDa proteins in B. amazonicus venom suggest scorpion neurotoxins. Purification and molecular characterization of these toxins are in course
Assessment and improvement of the 2D/1D method stability in DeCART
International Nuclear Information System (INIS)
As part of ongoing work with Consortium for Advanced Simulation of Light Water Reactors (CASL), the 2D/1D code, DeCART, has demonstrated some of the advantages of the 2D/1D method with respect to realistic, full-core analysis, particularly over explicit 3D transport methods, which generally have higher memory and computation requirements. The 2D/1D method performs 2D-radial transport sweeps coupled with ID-axial diffusion calculations to provide a full 3D simulation. DeCART employs the 2D method of characteristics for the radial sweeps and ID one-node nodal diffusion for the axial sweeps, coupling the two methods with transverse leakages to ensure a more consistent representation of the transport equation. It has been observed that refinement of the axial plane thickness leads to instabilities in the calculation scheme. This work assesses the sources of these instabilities and the approaches to improve them, especially with respect to negative scattering cross sections and the tightness of the 2D-radial/ID-axial coupling schemes. Fourier analyses show that the existing iteration scheme is not unconditionally stable, suggesting a tighter coupling scheme is required. For this reason 3D-CMFD has been implemented, among other developments, to ensure more stable calculation. A matrix of test cases has been used to assess the convergence, with the primary parameter being the axial plane thickness, which has been refined down to 1 cm. These cases demonstrate the issues observed and how the modification improve the stability. However, it is apparent that more work is necessary to ensure unconditional stability. (authors)
Advanced Fuel Cycle Initiative AFC-1D, AFC-1G and AFC-1H Irradiation Report
Energy Technology Data Exchange (ETDEWEB)
Debra J. Utterbeck; Gray Chang
2005-09-01
The U. S. Advanced Fuel Cycle Initiative (AFCI) seeks to develop and demonstrate the technologies needed to transmute the long-lived transuranic actinide isotopes contained in spent nuclear fuel into shorter-lived fission products, thereby dramatically decreasing the volume of material requiring disposition and the long-term radiotoxity and heat load of high-level waste sent to a geologic repository. The AFC-1 irradiation experiments on transmutation fuels are expected to provide irradiation performance data on non-fertile and low-fertile fuel forms specifically, irradiation growth and swelling, helium production, fission gas release, fission product and fuel constituent migration, fuel phase equilibria, and fuel-cladding chemical interaction. Contained in this report are the to-date physics evaluations performed on three of the AFC-1 experiments; AFC-1D, AFC-1G and AFC-1H. The AFC-1D irradiation experiment consists of metallic non-fertile fuel compositions with minor actinides for potential use in accelerator driven systems and AFC-1G and AFC-1H irradiation experiments are part of the fast neutron reactor fuel development effort. These experiments are high burnup analogs to previously irradiated experiments and are to be irradiated to = 20 atom % burnup. Results of the evaluations show that AFC-1D will remain in the ATR for approximately 100 additional effective full power days (EFPDs), and AFC-1G and AFC-1H for approximately 300 additional EFPDs in order to reach the desired programmatic burnup. The specific irradiation schedule for these tests will be determined based on future physics evaluations and all results will be documented in subsequent reports.
Assessment and improvement of the 2D/1D method stability in DeCART
Energy Technology Data Exchange (ETDEWEB)
Stimpson, S.; Young, M.; Collins, B.; Kelley, B.; Downar, T. [Department of Nuclear Engineering and Radiological Sciences, University of Michigan, 2355 Bonisteel Boulevard, Ann Arbor, MI 48109-2104 (United States)
2013-07-01
As part of ongoing work with Consortium for Advanced Simulation of Light Water Reactors (CASL), the 2D/1D code, DeCART, has demonstrated some of the advantages of the 2D/1D method with respect to realistic, full-core analysis, particularly over explicit 3D transport methods, which generally have higher memory and computation requirements. The 2D/1D method performs 2D-radial transport sweeps coupled with ID-axial diffusion calculations to provide a full 3D simulation. DeCART employs the 2D method of characteristics for the radial sweeps and ID one-node nodal diffusion for the axial sweeps, coupling the two methods with transverse leakages to ensure a more consistent representation of the transport equation. It has been observed that refinement of the axial plane thickness leads to instabilities in the calculation scheme. This work assesses the sources of these instabilities and the approaches to improve them, especially with respect to negative scattering cross sections and the tightness of the 2D-radial/ID-axial coupling schemes. Fourier analyses show that the existing iteration scheme is not unconditionally stable, suggesting a tighter coupling scheme is required. For this reason 3D-CMFD has been implemented, among other developments, to ensure more stable calculation. A matrix of test cases has been used to assess the convergence, with the primary parameter being the axial plane thickness, which has been refined down to 1 cm. These cases demonstrate the issues observed and how the modification improve the stability. However, it is apparent that more work is necessary to ensure unconditional stability. (authors)
A combined 1D/3D fuel burnup analysis of generation IV light water reactor IRIS
International Nuclear Information System (INIS)
A combined 1D/3D methodology for the fuel burnup analysis of generation IV light water reactors with thin boron coating that covers the fuel rods is described in this paper. This methodology is founded on three approximations. The first approximation assumes that the problem of fuel depletion in the entire 3D core can be resolved into two independent problems. One is a 3D Monte Carlo evolution of power distribution in large volumes (nodes) with the KENO-V.a code, and the other is a transport method evolution of burnup dependent fuel composition in 1D Wigner-Seitz cell for each node independently. With the second approximation, the time-dependent fuel composition in the node (e.g., in the fuel assembly) is calculated by using a 1D fuel depletion analysis with the SAS2H control module from the SCALE-4.4a code system. The third approximation involves smearing the boron coating with the clad (by volume homogenization). The proposed SAS2H/KENO-V.a methodology is verified for the case of 2D x-y model of IRIS 15x15 fuel assembly (with a reflective boundary condition) by using two well benchmarked code systems. The first one is MOCUP, a coupled MCNP-4C and ORIGEN2.1 utility code, and the second is KENO-V.a/ORIGEN2.1 code system recently developed by authors of this paper. It has been found that the proposed SAS2H/KENO-V.a methodology gives a satisfactory accuracy for keff and nuclide composition. Finally, this methodology was applied for 3D burnup analysis of IRIS-1000 benchmark≠44 core. Detailed keff and power density evolution with burnup are reported. (author)
Universal low-energy physics in 1D strongly repulsive multi-component Fermi gases
Jiang, Yuzhu; He, Peng; Guan, Xi-Wen
2016-04-01
It has been shown (Yang and You 2011 Chin. Phys. Lett. 28 020503) that at zero temperature the ground state of the one-dimensional (1D) w-component Fermi gas coincides with that of the spinless Bose gas in the limit ω \\to ∞ . This behavior was experimentally evidenced through quasi-1D tightly trapping ultracold 173Yb atoms in a recent paper (Pagano et al 2014 Nat. Phys. 10 198). However, understanding of low-temperature behavior of Fermi gases with a repulsive interaction requires spin-charge separated conformal field theories of an effective Tomonaga-Luttinger liquid and an antiferromagnetic SU(w) Heisenberg spin chain. Here we analytically derive universal thermodynamics of 1D strongly repulsive fermionic gases with SU(w) symmetry via the Yang-Yang thermodynamic Bethe ansatz method. The analytical free energy and magnetic properties of the systems at low temperature in a weak magnetic field are obtained through the Wiener-Hopf method. In particular, the free energy essentially manifests the spin-charge separated conformal field theories for high-symmetry systems with arbitrary repulsive interaction strength. We also find that the sound velocity of the Fermi gases in the large w limit coincides with that for the spinless Bose gas, whereas the spin velocity vanishes quickly as w becomes large. This indicates strong suppression of the Fermi exclusion statistics by the commutativity feature among the w-component fermions with different spin states in the Tomonaga-Luttinger liquid phase. Moreover, the equations of state and critical behavior of physical quantities at finite temperature are analytically derived in terms of the polylogarithm functions in the quantum critical region.
Suzuki, Toshinori
2014-06-01
The scattering distributions of state-selected methyl radicals are measured for the O(^1D_2) reaction with methane using a crossed molecular beam ion imaging method at collision energies of 0.9 - 6.8 kcal/mol. The results are compared with the reaction with deuterated methane to examine the isotope effects. The scattering distributions exhibit contributions from both the insertion and abstraction pathways respectively on the ground and excited-state potential energy surfaces. Insertion is the main pathway, and it provides a strongly forward-enhanced angular distribution of methyl radicals. Abstraction is a minor pathway, causing backward scattering of methyl radicals with a discrete speed distribution. From the collision energy dependence of the abstraction/insertion ratio, the barrier height for the abstraction pathway is estimated for O(^1D_2) with CH_4 and CD_4, respectively. The insertion pathway of the O(^1D_2) reaction with CH_4 has a narrower angular width in the forward scattering and a larger insertion/abstraction ratio than the reaction with CD_4, which indicate that the insertion reaction with CH_4 has a larger cross section and a shorter reaction time than the reaction with CD_4. Additionally, while the insertion reaction with CD_4 exhibits strong angular dependence of the CD_3 speed distribution, CH_3 exhibits considerably smaller dependence. The result suggests that, although intramolecular vibrational redistribution (IVR) within the lifetime of the methanol intermediate is restrictive in both isotopomers, relatively more extensive IVR occurs in CD_3OD than CH_3OH, presumably due to the higher vibrational state density.
Polat, Orhan; Özer, Ćaglar
2016-04-01
In this study; we examined one dimensional crustal velocity structure of Izmir gulf and surroundings. We used nearly one thousand high quality (A and B class) earthquake data which recorded by Disaster and Emergency Management Presidency (AFAD) [1], Bogazici University (BU-KOERI) [2] and National Observatory of Athens (NOA) [3,4]. We tried several synthetic tests to understand power of new velocity structure, and examined phase residuals, RMS values and shifting tests. After evaluating these tests; we decided one dimensional velocity structure and minimum 1-D P wave velocities, hypocentral parameter and earthquake locations from VELEST algorithm. Distribution of earthquakes was visibly improved by using new minimum velocity structure.
B Cells Promote Th1- Skewed NKT Cell Response by CD1d-TCR Interaction
Shin, Jung Hoon; Park, Se-Ho
2013-01-01
CD1d expressing dendritic cells (DCs) are good glyco-lipid antigen presenting cells for NKT cells. However, resting B cells are very weak stimulators for NKT cells. Although α-galactosylceramide (α-GalCer) loaded B cells can activate NKT cells, it is not well defined whether B cells interfere NKT cell stimulating activity of DCs. Unexpectedly, we found in this study that B cells can promote Th1-skewed NKT cell response, which means a increased level of IFN-γ by NKT cells, concomitant with a d...
Numerical modeling of 1-D transient poroelastic waves in the low-frequency range
Chiavassa, Guillaume; Piraux, Joël
2007-01-01
Propagation of transient mechanical waves in porous media is numerically investigated in 1D. The framework is the linear Biot's model with frequency-independant coefficients. The coexistence of a propagating fast wave and a diffusive slow wave makes numerical modeling tricky. A method combining three numerical tools is proposed: a fourth-order ADER scheme with time-splitting to deal with the time-marching, a space-time mesh refinement to account for the small-scale evolution of the slow wave, and an interface method to incorporate the jump conditions at interfaces. Comparisons with analytical solutions confirm the validity of this approach.
D1/D5 system and Wilson Loops in (Non-)commutative Gauge Theories
Takahashi, Hidenori; Nakajima, Tadahito; Suzuki, Kenji
2002-01-01
We study the behavior of the Wilson loop in the (5+1)-dimensional supersymmetric Yang-Mills theory with the presence of the solitonic object. Using the dual string description of the Yang-Mills theory that is given by the D1/D5 system, we estimate the Wilson loops both in the temporal and spatial cases. For the case of the temporal loop, we obtain the velocity dependent potential. For the spatial loop, we find that the area law is emerged due to the effect of the D1-branes. Further, we consid...
Evaluation of EMG signals Compression by JPEG 2000 called 1D
Directory of Open Access Journals (Sweden)
Ntsama Eloundou Pascal
2013-02-01
Full Text Available In this paper, we are conducting an evaluation the compression of electromyographic signals (EMG through of standard modified JPEG 2000 called 1D. We illustrate that; this method can also be used to compress EMG signals. The technique consists of cutting the signal into small segments or micro vectors. The EMG signal compression through this method aims at solving the problems of transmission and optimizes storage. A comparison of the results obtained with those of the literature shows a net improvement. The results obtained on real signals are presented in terms of the objective criteria ofevaluating performance.
Quadratic gravity in (2+1)D with a topological Chern-Simons term
International Nuclear Information System (INIS)
Three-dimensional quadratic gravity, unlike general relativity in (2+1)D, is dynamically nontrivial and has a well behaved nonrelativistic potential. Here we analyse the changes that occur when a topological Chern-Simons term is added to this theory. It is found that the harmless massive scalar mode of the latter gives rise to a troublesome massive spin-0 ghost, while the massive spin-2 ghost is replaced by two massive physical particles both of spin 2. We also found that light deflection does not have the 'wrong sign' such as in the framework of three-dimensional quadratic gravity. (author)
Electronic and Transport Properties of Quasi-1D Wires of Biological Molecules
Oetzel, Björn; Matthes, Lars; Tandetzky, Falk; Ortmann, Frank; Bechstedt, Friedhelm; Hannewald, Karsten
2010-03-01
In the search for organic materials with good charge-transport properties, artificial stacks of biological molecules are considered attractive candidates [1,2]. In this spirit, we present ab-initio DFT calculations of the structural, electronic, and quantum-transport properties of quasi-1D wires based on guanine and eumelanin molecules [3]. Hereby, a special focus is put on the results for the electronic bandwidths and the consequences for potential applications. [4pt] [1] R. di Felice et al., Phys. Rev. B 65, 045104 (2001) [0pt] [2] P. Meredith et al., Pigment Cell Res. 19, 572 (2006) [0pt] [3] B. Oetzel et al. (unpublished)
Thermodynamic nature of vitrification in a 1D model of a structural glass former
International Nuclear Information System (INIS)
We propose a new spin-glass model with no positional quenched disorder which is regarded as a coarse-grained model of a structural glass-former. The model is analyzed in the 1D case when the number N of states of a primary cell is large. For N → ∞, the model exhibits a sharp freezing transition of the thermodynamic origin. It is shown both analytically and numerically that the glass transition is accompanied by a significant growth of a static length scale ξ pointing to the structural (equilibrium) nature of dynamical slowdown effects in supercooled liquids
System for Digital 1D-Image Processing with 1024 Pixel CCD Sensor
J. Misun; M. Chrenek; Sevcik, P; P. Kulla
1993-01-01
The conception of system for digital 1D-images processing with digital CCD camera is presented. The system is created from these three basic parts: the digital CCD camera with linear image sensor CCD L133C, 8-bit interface and a personal computer. The scanning digital CCD camera generated a video signals, which are processed in the analog signal processor. The output signal is continually converted to 8-bit data words in A/D converter. This data words maybe transfer over a bus driver to the o...
Cold beam of isotopically pure Yb atoms by deflection using 1D-optical molasses
Indian Academy of Sciences (India)
K D Rathod; P K Singh; Vasant Natarajan
2014-09-01
We demonstrate the generation of an isotopically pure beam of laser-cooled Yb atoms by deflection using 1D-optical molasses. Atoms in a collimated thermal beam are first slowed using a Zeeman slower. They are then subjected to a pair of molasses beams inclined at 45° with respect to the slowed atomic beam. The slowed atoms are deflected and probed at a distance of 160 mm. We demonstrate the selective deflection of the bosonic isotope 174Yb and the fermionic isotope 171Yb. Using a transient measurement after the molasses beams are turned on, we find a longitudinal temperature of 41 mK.
Cold beam of isotopically pure Yb atoms by deflection using 1D-optical molasses
Rathod, KD; Singh, PK; Natarajan, Vasant
2014-01-01
We demonstrate the generation of an isotopically pure beam of laser-cooled Yb atoms by deflection using 1D-optical molasses. Atoms in a collimated thermal beam are first slowed using a Zeeman slower. They are then subjected to a pair of molasses beams inclined at 45(a similar to) with respect to the slowed atomic beam. The slowed atoms are deflected and probed at a distance of 160 mm. We demonstrate the selective deflection of the bosonic isotope Yb-174 and the fermionic isotope Yb-171. Using...
Cold beam of isotopically pure Yb atoms by deflection using 1D-optical molasses
Rathod, K. D.; Singh, P. K.; Natarajan, Vasant
2014-09-01
We demonstrate generation of an isotopically pure beam of laser-cooled Yb atoms by deflection using 1D-optical molasses. Atoms in a collimated thermal beam are first slowed using a Zeeman Slower. They are then subjected to a pair of molasses beams inclined at $45^\\circ$ with respect to the slowed atomic beam. The slowed atoms are deflected and probed at a distance of 160 mm. We demonstrate selective deflection of the bosonic isotope $^{174}$Yb, and the fermionic isotope $^{171}$Yb. Using a transient measurement after the molasses beams are turned on, we find a longitudinal temperature of 41 mK.
Cold beam of isotopically pure Yb atoms by deflection using 1D-optical molasses
Rathod, K D; Natarajan, Vasant
2013-01-01
We demonstrate generation of an isotopically pure beam of laser-cooled Yb atoms by deflection using 1D-optical molasses. Atoms in a collimated thermal beam are first slowed using a Zeeman Slower. They are then subjected to a pair of molasses beams inclined at $45^\\circ$ with respect to the slowed atomic beam. The slowed atoms are deflected and probed at a distance of 160 mm. We demonstrate selective deflection of the bosonic isotope $^{174}$Yb, and the fermionic isotope $^{171}$Yb. Using a transient measurement after the molasses beams are turned on, we find a longitudinal temperature of 41 mK.
Thermal impedance at the interface of contacting bodies: 1-D examples solved by semi-derivatives
Directory of Open Access Journals (Sweden)
Hristov Jordan
2012-01-01
Full Text Available Simple 1-D semi-infinite heat conduction problems enable to demonstrate the potential of the fractional calculus in determination of transient thermal impedances of two bodies with different initial temperatures contacting at the interface ( x = 0 at t = 0 . The approach is purely analytic and uses only semi-derivatives (half-time and semi-integrals in the Riemann-Liouville sense. The example solved clearly reveals that the fractional calculus is more effective in calculation the thermal resistances than the entire domain solutions.
Towards 1D nanolines on a monolayered supramolecular network adsorbed on a silicon surface
Makoudi, Younes; Beyer, Matthieu; Lamare, Simon; Jeannoutot, Judicael; Palmino, Frank; Chérioux, Frédéric
2016-06-01
The growth of 3D extended periodic networks made up of π-conjugated molecules on semi-conductor surfaces is of interest for the integration of nano-components in the future generations of smart devices. In the work presented in this article, we successfully achieved the formation of bilayered networks on a silicon surface including 1D-isolated nanolines in the second layer. Firstly, we observed the formation of a 2D large-scale supramolecular network in the plane of a silicon surface through the deposition of tailored molecules. Then using the same molecules, a second-layer, based on 1D nanolines, grew above the first layer, thanks to a template effect. Mono- or bi-layered networks were found to be stable from 100 K up to room temperature. These networks were investigated by scanning tunnel microscopy imaging under an ultra-high vacuum (UHV-STM).The growth of 3D extended periodic networks made up of π-conjugated molecules on semi-conductor surfaces is of interest for the integration of nano-components in the future generations of smart devices. In the work presented in this article, we successfully achieved the formation of bilayered networks on a silicon surface including 1D-isolated nanolines in the second layer. Firstly, we observed the formation of a 2D large-scale supramolecular network in the plane of a silicon surface through the deposition of tailored molecules. Then using the same molecules, a second-layer, based on 1D nanolines, grew above the first layer, thanks to a template effect. Mono- or bi-layered networks were found to be stable from 100 K up to room temperature. These networks were investigated by scanning tunnel microscopy imaging under an ultra-high vacuum (UHV-STM). Electronic supplementary information (ESI) available: Additional STM images showing submolecular details of the adsorption of molecules on the surface. See DOI: 10.1039/c6nr01826b
Simulation of Tunnel Junction in Cascade Solar Cell (GaAs/Ge Using AMPS-1D
Directory of Open Access Journals (Sweden)
Benmoussa Dennai
2014-11-01
Full Text Available The development of the tunnel junction interconnect was key the first two-terminal monolithic, multi-junction solar cell development. This paper describes simulation for the tunnel junction (GaAs between top cell (GaAs and bottom cell (Ge. This solar cell cascade was simulated when using one dimensional simulation program called analysis of microelectronic and photonic structures (AMPS-1D. In the simulation, the thickness of the tunnel junction layer was varied from 10 to 50 nm. By varying thickness of tunnel junction layer the simulated device performance was demonstrate in the form of current-voltage(I-V characteristics and quantum efficiency (QE.
Silva. EDF two-phase 1D annular model of a CFB boiler furnace
Energy Technology Data Exchange (ETDEWEB)
Montat, D.; Fauquet, Ph. [Electricite de France (EDF), 78 - Chatou (France). Researckh and Development Div.; Lafanechere, L.; Bursi, J.M. [Electricite de France (EDF) (France). Construction Div.
1997-01-01
SILVA computer code is used for the modelling of the thermal-hydraulics and of the combustion of a coal-fired CFBC solid loop. In a first step, only the furnace is considered. The model is based on a 1D annular two phases description of the hydrodynamics. The model is based on particle mass balances and pressure drop calculations. A basic combustion model is incorporated into this model. The coal combustion is divided in two phases, the combustion of volatile matter and the heterogeneous combustion. The model has been developed within LEGO software and can be included into the global model of the solid loop developed by EDF. (author) 26 refs.
Correlation versus surface effects in photoemission of quasi-1D organic conductors
DEFF Research Database (Denmark)
Claessen, R.; Schwingenschlogl, U.; Sing, M.; Jacobsen, Claus Schelde; Dressel, M.
2002-01-01
The absence of spectral weight at the Fermi level in photoemission spectra of quasi-1D organic conductors has been interpreted as possible evidence for an unusual many-body state. We demonstrate that great care must be exercised to draw this conclusion exclusively on the basis of a pseudogap. A...... detailed surface characterization of the charge transfer salts (TMTSF)(2)PFt(6) and TTF-TCNQ shows that signatures of electronic correlations in the valence band spectra are strongly affected by surface effects and may even be completely obscured....
Superfluid behavior of quasi-1D p-H$_2$ inside carbon nanotube
Rossi, Maurizio; Ancilotto, Francesco
2016-01-01
We perform ab-initio Quantum Monte Carlo simulations of para-hydrogen (pH$_2$) at $T=0$ K confined in carbon nanotubes (CNT) of different radii. The radial density profiles show a strong layering of the pH$_2$ molecules which grow, with increasing number of molecules, in solid concentric cylindrical shells and eventually a central column. The central column can be considered an effective one-dimensional (1D) fluid whose properties are well captured by the Tomonaga-Luttinger liquid theory. The...
Statistical mechanics of a one-component fluid of charged hard rods in 1D
International Nuclear Information System (INIS)
The statistical mechanics of a classical one component system of charged hard rods in a neutralizing background is investigated in 1D stressing on the effects of the hard core interactions over the thermodynamic and the structure of the system. The crystalline status of the system at all temperatures and densities and the absence of phase transitions is shown by extending previous results of Baxter and Kunz on the one-component plasma of point particles. Explicit expressions for the thermodynamic functions and the one-particle correlation function are given in the limits of small and strong couplings. (author)
Observation of Reduced Three-Body Recombination in a Fermionized 1D Bose Gas
Tolra, B. Laburthe; O'Hara, K. M.; Huckans, J. H.; Phillips, W. D.; Rolston, S. L.; Porto, J. V.
2003-01-01
We investigate correlation properties of a one-dimensional interacting Bose gas by loading a magnetically trapped 87-Rb Bose-Einstein condensate into a deep two-dimensional optical lattice. We measure the three-body recombination rate for both the BEC in the magnetic trap and the BEC loaded into the optical lattice. The recombination rate coefficient is a factor of seven smaller in the lattice, which we interpret as a reduction in the local three-body correlation function in the 1D case. This...
Hair on non-extremal D1-D5 bound states
Roy, Pratik; Virmani, Amitabh
2016-01-01
We consider a truncation of type IIB supergravity on four-torus where in addition to the Ramond-Ramond 2-form field, the Ramond-Ramond axion (w) and the NS-NS 2-form field (B) are also retained. In the (w, B) sector we construct a linearised perturbation carrying only left moving momentum on two-charge non-extremal D1-D5 geometries of Jejjala, Madden, Ross and Titchener. The perturbation is found to be smooth everywhere and normalizable. It is constructed by matching to leading order solutions of the perturbation equations in the inner and outer regions of the geometry.
Maximizing 1D “like” implosion performance for inertial confinement fusion science
Energy Technology Data Exchange (ETDEWEB)
Kline, John L. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2016-07-15
While the march towards achieving indirectly driven inertial confinement fusion at the NIF has made great progress, the experiments show that multi-dimensional effects still dominate the implosion performance. Low mode implosion symmetry and hydrodynamic instabilities seed by capsule mounting features appear to be two key limiting factors for implosion performance. One reason these factors have a large impact on the performance of ICF implosions is the high convergence required to achieve high fusion gains. To tackle these problems, a predictable implosion platform is needed meaning experiments must trade-off high gain for performance. To this end, LANL has adopted three main approaches to develop a 1D implosion platform where 1D means high yield over 1D clean calculations. Taking advantage of the properties of beryllium capsules, a high adiabat, low convergence platform is being developed. The higher drive efficiency for beryllium enables larger case-to-capsule ratios to improve symmetry at the expense of drive. Smaller capsules with a high adiabat drive are expected to reduce the convergence and thus increase predictability. The second approach is liquid fuel layers using wetted foam targets. With liquid fuel layers, the initial mass in the hot spot can be controlled via the target fielding temperature which changes the liquid vapor pressure. Varying the initial hot spot mass via the vapor pressure controls the implosion convergence and minimizes the need to vaporize the dense fuel layer during the implosion to achieve ignition relevant hot spot densities. The last method is double shell targets. Unlike hot spot ignition, double shells ignite volumetrically. The inner shell houses the DT fuel and the convergence of this cavity is relatively small compared to hot spot ignition. Radiation trapping and the longer confinement times relax the conditions required to ignite the fuel. Key challenges for double shell targets are coupling the momentum of the outer shell to
Editing of CD1d-Bound Lipid Antigens by Endosomal Lipid Transfer Proteins
Zhou, Dapeng; Cantu, Carlos; Sagiv, Yuval; Schrantz, Nicolas; Kulkarni, Ashok B.; Qi, Xiaoyang; Mahuran, Don J.; Carlos R Morales; Grabowski, Gregory A.; Benlagha, Kamel; Savage, Paul; Bendelac, Albert; Teyton, Luc
2003-01-01
It is now established that CD1 molecules present lipid antigens to T cells, although it is not clear how the exchange of lipids between membrane compartments and the CD1 binding groove is assisted. We report that mice deficient in prosaposin, the precursor to a family of endosomal lipid transfer proteins (LTP), exhibit specific defects in CD1d-mediated antigen presentation and lack Vα14 NKT cells. In vitro, saposins extracted monomeric lipids from membranes and from CD1, thereby promoting the...
Monochromatic Neutron Tomography Using 1-D PSD Detector at Low Flux Research Reactor
Ashari, N. Abidin; Saleh, J. Mohamad; Abdullah, M. Zaid; Mohamed, A. Aziz; Azman, A.; Jamro, R.
2008-03-01
This paper describes the monochromatic neutron tomography experiment using the 1-D Position Sensitive Neutron Detector (PSD) located at Nuclear Malaysia TRIGA MARK II Research reactor. Experimental work was performed using monochromatic neutron source from beryllium filter and HOPG crystal monochromator. The principal main aim of this experiment was to test the detector efficiency, image reconstruction algorithm and the usage of 0.5 nm monochromatic neutrons for the neutron tomography setup. Other objective includes gathering important parameters and features to characterize the system.
Schmidts, M.; Hou, Y; Cortes, C.R.; Mans, D. A.; Huber, C.; Boldt, K.; M. Patel; Van Reeuwijk, J; Plaza, J.M.; Beersum, S.E.C; Yap, Z.M.; Letteboer, S.J.F.; Taylor, S. P.; Herridge, W; Johnson, C A
2015-01-01
ARTICLE Received 1 Oct 2014 | Accepted 31 Mar 2015 | Published 5 June 2015 TCTEX1D2 mutations underlie Jeune asphyxiating thoracic dystrophy with impaired retrograde intraflagellar transport Miriam Schmidts1,2,3,4,*, Yuqing Hou5,*, Claudio R. Corte´s6, Dorus A. Mans2,3, Celine Huber7, Karsten Boldt8, Mitali Patel1, Jeroen van Reeuwijk2,3, Jean-Marc Plaza9, Sylvia E.C. van Beersum2,3, Zhi Min Yap1, Stef J.F. Letteboer2,3, S Paige Taylor10, Warren Herridge11, Colin A. Johns...
Effect of low transverse magnetic field on the confinement strength in a quasi-1D wire
Energy Technology Data Exchange (ETDEWEB)
Kumar, Sanjeev [London Centre for Nanotechnology, University College London, 17-19 Gordon Street, London WC1H 0AH (United Kingdom); Thomas, K. J. [London Centre for Nanotechnology, University College London, 17-19 Gordon Street, London WC1H 0AH, UK and Department of Electronic and Electrical Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Smith, L. W.; Farrer, I.; Ritchie, D. A.; Jones, G. A. C.; Griffiths, J. [Cavendish Laboratory, J. J. Thomson Avenue, Cambridge CB3 OHE (United Kingdom); Pepper, M. [London Centre for Nanotechnology, University College London, 17-19 Gordon Street, London WC1H 0AH, UK and Department of Electrical and Electronic Engineering, Torrington Place, London WC1E 7JE (United Kingdom)
2013-12-04
Transport measurements in a quasi-one dimensional (1D) quantum wire are reported in the presence of low transverse magnetic field. Differential conductance shows weak quantised plateaus when the 2D electrons are squeezed electrostatically. Application of a small transverse magnetic field (0.2T) enhances the overall degree of quantisation due to the formation of magneto-electric subbands. The results show the role of magnetic field to fine tune the confinement strength in low density wires when interaction gives rise to double row formation.
Prediction of car cabin environment by means of 1D and 3D cabin model
Fišer, J.; Pokorný, J.; Jícha, M.
2012-04-01
Thermal comfort and also reduction of energy requirements of air-conditioning system in vehicle cabins are currently very intensively investigated and up-to-date issues. The article deals with two approaches of modelling of car cabin environment; the first model was created in simulation language Modelica (typical 1D approach without cabin geometry) and the second one was created in specialized software Theseus-FE (3D approach with cabin geometry). Performance and capabilities of this tools are demonstrated on the example of the car cabin and the results from simulations are compared with the results from the real car cabin climate chamber measurements.
Prediction of car cabin environment by means of 1D and 3D cabin model
Directory of Open Access Journals (Sweden)
Jícha M.
2012-04-01
Full Text Available Thermal comfort and also reduction of energy requirements of air-conditioning system in vehicle cabins are currently very intensively investigated and up-to-date issues. The article deals with two approaches of modelling of car cabin environment; the first model was created in simulation language Modelica (typical 1D approach without cabin geometry and the second one was created in specialized software Theseus-FE (3D approach with cabin geometry. Performance and capabilities of this tools are demonstrated on the example of the car cabin and the results from simulations are compared with the results from the real car cabin climate chamber measurements.
Exact spin dynamics of inhomogeneous 1-d systems at high temperature
Danieli, E. P.; Pastawski, H. M.; Levstein, P. R.
2002-07-01
The evaluation of spin excitation dynamics in finite 1-d systems of spins {1}/{2} with XY exchange interaction J acquired new interest because NMR experiments at high temperature ( kBT≫ J) confirmed the predicted spin wave behavior of mesoscopic echoes. In this work, we use the Jordan-Wigner transformation to obtain the exact dynamics of inhomogeneous chains and rings where the evolution is reduced to one-body dynamics. For higher dimensions, the spin excitations manifest many-body effects that can be interpreted as a simple dynamics of non-interacting fermions plus a decoherent process.
Synthesis, Characterization, and Application of 1-D Cerium Oxide Nanomaterials: A Review
Directory of Open Access Journals (Sweden)
Kuen-Song Lin
2010-09-01
Full Text Available The present work provides a comprehensive overview of the recent progress of research work toward developing new one dimensional (1-D ceria (CeO2 nanomaterials. The review has been classified into three parts: the preparation procedures with identification of the existing different dimensional ceria nanomaterials, the formation mechanisms, and an analysis of their applications. From literature survey, it is inaugurated that the fundamental structures of the ceria nanomaterials constructively dominate their properties and applications. In addition, this work will also provide a perspective on the future technical trends for the development of different dimensional CeO2 nanomaterials.
Experimental Conditions: SE37_S04_M1_D1 [Metabolonote[Archive
Lifescience Database Archive (English)
Full Text Available SE37_S04_M1_D1 SE37 Medicago truncatula shoot metabolite analysis using stable isot...opes SE37_S04 13C-labeled Medicago truncatula Jemalong A17 shoot SE37_S04_M1 0.25mg Metabolites were extract...ed from 10.81mg of plant sample. [MassBase ID] MDLC1_43502 SE37_MS1 Metabolites extraction with 80% methanol... and analysis by LC-Orbitrap-MS SE37_DS2 Peak extraction for labeled data 6|ITMS 2 ...
GE SBWR stability analysis using TRAC-BF1 1-D kinetics model
International Nuclear Information System (INIS)
GE's simplified boiling water reactor, with its unique feature of using natural circulation to remove the heat from the reactor core, is a complicated dynamic system. Previous work by authors using the TRAC-BF1 code and a point kinetics model predicted that an SBWR may experience large amplitude power oscillation under certain low pressure and high power operating conditions. To further confirm the existence of this power oscillation and explore the dynamic spatial reactor power distribution, the TRAC-BF1 1-D kinetics model was used. The results show that an instability exists and the power oscillation starting time and maximum peak power are different from the point kinetics results
Second order effect of twist deformation in the D1D5 CFT
Carson, Zaq; Mathur, Samir D
2015-01-01
Thermalization in the D1D5 CFT should occur via interactions caused by the twist operator, which deforms the theory off its free orbifold point. Earlier studies investigating this deformation at first order did not show any definite evidence of thermalization. In this paper we study the deformation to second order, where we do expect to see the effects that should give thermalization. We compute the effect of two twist operators on an initial vacuum state, which generates a squeezed state analogous to the case for a single twist. We obtain expressions for the Bogoliubov coefficients in this 2-twist case.
Correlation versus surface effects in photoemission of quasi-1D organic conductors
DEFF Research Database (Denmark)
Claessen, R.; Schwingenschlogl, U.; Sing, M.; Jacobsen, Claus Schelde; Dressel, M.
2002-01-01
The absence of spectral weight at the Fermi level in photoemission spectra of quasi-1D organic conductors has been interpreted as possible evidence for an unusual many-body state. We demonstrate that great care must be exercised to draw this conclusion exclusively on the basis of a pseudogap. A d...... detailed surface characterization of the charge transfer salts (TMTSF)(2)PFt(6) and TTF-TCNQ shows that signatures of electronic correlations in the valence band spectra are strongly affected by surface effects and may even be completely obscured....
Del Buffa, Stefano; Rinaldi, Elia; Carretti, Emiliano; Ridi, Francesca; Bonini, Massimo; Baglioni, Piero
2016-09-01
The use of injectable materials in minimally invasive surgical procedures could help in facing the bone diseases connected to the ageing of world population. To this aim, materials integrating the rheological properties of biocompatible polymers with the mechanical properties of 1D inorganic nanostructures represent promising scaffolds. Here we describe the preparation of hydrogel composites made of carboxymethyl cellulose (CMC) and halloysite nanotubes (HNT) as injectable materials for the local treatment of bone defects. The rheology and injectability of the materials reflects their structural properties, showing the possibility of successfully injecting the prepared composites over a large range of operative conditions. PMID:27281242
Scratched-XY Universality and Phase Diagram of Disordered 1D Bosons in Optical Lattice
Yao, Zhiyuan; Pollet, Lode; Prokof'ev, Nikolay; Svistunov, Boris
The superfluid-insulator quantum phase transition in a 1D system with weak links belongs to the so-called scratched-XY universality class, provided the irrenormalizable exponent ζ characterizing the distribution of weak links is smaller than 2 / 3 . With a combination of worm-algorithm Monte Carlo simulations and asymptotically exact analytics, we accurately trace the position of the scratched-XY critical line on the ground-state phase diagram of bosonic Hubbard model at unity filling. In particular, we reveal the location of the tricritical point separating the scratched-XY criticality from the Giamarchi-Schulz one.
Analysis of Flash Flood Routing by Means of 1D - Hydraulic Modelling
Tesfay Abraha, Zerisenay
2013-01-01
This study was conducted at the mountainous catchment part of Batinah Region of the Sultanate of Oman called Al-Awabi watershed which is about 260km2 in area with about 40 Km long Wadi main channel. The study paper presents a proposed modeling approach and possible scenario analysis which uses 1D - hydraulic modeling for flood routing analysis; and the main tasks of this study work are (1) Model setup for Al-Awabi watershed area, (2) Sensitivity Analysis, and (3) Scenario Analysis on impacts ...
Analytical solution to the Riemann problem of 1D elastodynamics with general constitutive laws
Berjamin, H; Chiavassa, G; Favrie, N
2016-01-01
Under the hypothesis of small deformations, the equations of 1D elastodynamics write as a 2 x 2 hyperbolic system of conservation laws. Here, we study the Riemann problem for convex and nonconvex constitutive laws. In the convex case, the solution can include shock waves or rarefaction waves. In the nonconvex case, compound waves must also be considered. In both convex and nonconvex cases, a new existence criterion for the initial velocity jump is obtained. Also, admissibility regions are determined. Lastly, analytical solutions are completely detailed for various constitutive laws (hyperbola, tanh and polynomial), and reference test cases are proposed.
Institute of Scientific and Technical Information of China (English)
无
2009-01-01
10月20日佳能（中国）有限公司发布面向职业新闻和体育摄影师的专业数码单反相机EOS-1D Mark IV和支持有线／无线网络及USB控制功能EOS 5D Mark II无线文件传输器WFT-E4 II C为专业影像市场注入了全新的技术动力。
Design for manufacturability from 1D to 4D for 90-22 nm technology nodes
Balasinski, Artur
2013-01-01
This book explains integrated circuit design for manufacturability (DfM) at the product level (packaging, applications) and applies engineering DfM principles to the latest standards of product development at 22 nm technology nodes.Â It is a valuable guide for layout designers, packaging engineers and quality engineers, covering DfM development from 1D to 4D, involving IC design flow setup, best practices, links to manufacturing and product definition, for process technologies down to 22 nm node, and product families including memories, logic, system-on-chip and system-in-package.
Timed arrays wideband and time varying antenna arrays
Haupt, Randy L
2015-01-01
Introduces timed arrays and design approaches to meet the new high performance standards The author concentrates on any aspect of an antenna array that must be viewed from a time perspective. The first chapters briefly introduce antenna arrays and explain the difference between phased and timed arrays. Since timed arrays are designed for realistic time-varying signals and scenarios, the book also reviews wideband signals, baseband and passband RF signals, polarization and signal bandwidth. Other topics covered include time domain, mutual coupling, wideband elements, and dispersion. The auth
Severe hypoglycemia (SH) and diabetic ketoacidosis (DKA) are common serious acute complications of type 1 diabetes (T1D). The aim of this study was to determine the frequency of SH and DKA and identify factors related to their occurrence in the T1D Exchange pediatric and young adult cohort. The anal...
REFLA-1D/MODE3: a computer code for reflood thermo-hydrodynamic analysis during PWR-LOCA
International Nuclear Information System (INIS)
This manual describes the REFLA-1D/MODE3 reflood system analysis code. This code can solve the core thermo-hydrodynamics under forced flooding conditions and gravity feed conditions in a system similar to FLECHT-SET Phase A. This manual describes the REFLA-1D/MODE3 models and provides application information required to utilize the code. (author)
Wiktor, Peter; Brunner, Al; Kahn, Peter; Qiu, Ji; Magee, Mitch; Bian, Xiaofang; Karthikeyan, Kailash; Labaer, Joshua
2015-03-01
We report a device to fill an array of small chemical reaction chambers (microreactors) with reagent and then seal them using pressurized viscous liquid acting through a flexible membrane. The device enables multiple, independent chemical reactions involving free floating intermediate molecules without interference from neighboring reactions or external environments. The device is validated by protein expressed in situ directly from DNA in a microarray of ~10,000 spots with no diffusion during three hours incubation. Using the device to probe for an autoantibody cancer biomarker in blood serum sample gave five times higher signal to background ratio compared to standard protein microarray expressed on a flat microscope slide. Physical design principles to effectively fill the array of microreactors with reagent and experimental results of alternate methods for sealing the microreactors are presented.
Optically interconnected phased arrays
Bhasin, Kul B.; Kunath, Richard R.
1988-01-01
Phased-array antennas are required for many future NASA missions. They will provide agile electronic beam forming for communications and tracking in the range of 1 to 100 GHz. Such phased arrays are expected to use several hundred GaAs monolithic integrated circuits (MMICs) as transmitting and receiving elements. However, the interconnections of these elements by conventional coaxial cables and waveguides add weight, reduce flexibility, and increase electrical interference. Alternative interconnections based on optical fibers, optical processing, and holography are under evaluation as possible solutions. In this paper, the current status of these techniques is described. Since high-frequency optical components such as photodetectors, lasers, and modulators are key elements in these interconnections, their performance and limitations are discussed.
Atacama Compact Array Antennas
Saito, Masao; Nakanishi, Kouichiro; Naoi, Takahiro; Yamada, Masumi; Saito, Hiro; Ikenoue, Bungo; Kato, Yoshihiro; Morita, Kou-ichiro; Mizuno, Norikazu; Iguchi, Satoru
2011-01-01
We report major performance test results of the Atacama Compact Array (ACA) 7-m and 12-m antennas of ALMA (Atacama Large Millimeter/submillimeter Array). The four major performances of the ACA antennas are all-sky pointing (to be not more than 2.0 arcsec), offset pointing (to be < 0.6 arcsec) surface accuracy (< 25(20) micrometer for 12(7)m-antenna), stability of path-length (15 micrometer over 3 min), and high servo capability (6 degrees/s for Azimuth and 3 degrees/s for Elevation). The high performance of the ACA antenna has been extensively evaluated at the Site Erection Facility area at an altitude of about 2900 meters. Test results of pointing performance, surface performance, and fast motion capability are demonstrated.
Mitchell, Daniel A; Ord, Stephen M; Bernardi, Gianni; Wayth, Randall B; Edgar, Richard G; Clark, Michael A; Dal, Kevin; Pfister, Hanspeter; Gleadow, Stewart J; Arcus, W; Briggs, F H; Benkevitch, L; Bowman, J D; Bunton, J D; Burns, S; Cappallo, R J; Corey, B E; de Oliveira-Costa, A; Desouza, L; Doeleman, S S; Derome, M F; Emrich, D; Glossop, M; Goeke, R; Krishna, M R Gopala; Hazelton, B; Herne, D E; Hewitt, J N; Kamini, P A; Kaplan, D L; Kasper, J C; Kincaid, B B; Kocz, J; Kowald, E; Kratzenberg, E; Kumar, D; Lonsdale, C J; Lynch, M J; Madhavi, S; Matejek, M; McWhirter, S R; Morales, M F; Morgan, E; Oberoi, D; Pathikulangara, J; Prabu, T; Rogers, A; Salah, J E; Sault, R J; Shankar, N Udaya; Srivani, K S; Stevens, J; Tingay, S J; Vaccarella, A; Waterson, M; Webster, R L; Whitney, A R; Williams, A; Williams, C
2010-01-01
It is shown that the excellent Murchison Radio-astronomy Observatory site allows the Murchison Widefield Array to employ a simple RFI blanking scheme and still calibrate visibilities and form images in the FM radio band. The techniques described are running autonomously in our calibration and imaging software, which is currently being used to process an FM-band survey of the entire southern sky.
Lazio, Joseph
2009-01-01
The Square Kilometre Array (SKA) is intended as the next-generation radio telescope and will address fundamental questions in astrophysics, physics, and astrobiology. The international science community has developed a set of Key Science Programs: (1) Emerging from the Dark Ages and the Epoch of Reionization, (2) Galaxy Evolution, Cosmology, and Dark Energy, (3) The Origin and Evolution of Cosmic Magnetism, (4) Strong Field Tests of Gravity Using Pulsars and Black Holes, and (5) The Cradle of...
Bigongiari, Ciro
2016-01-01
The Cherenkov Telescope Array (CTA) is planned to be the next generation ground based observatory for very high energy (VHE) gamma-ray astronomy. Gamma-rays provide a powerful insight into the non-thermal universe and hopefully a unique probe for new physics. Imaging Cherenkov telescopes have already discovered more than 170 VHE gamma-ray emitters providing plentiful of valuable data and clearly demonstrating the power of this technique. In spite of the impressive results there are indication...
The Submillimeter Array Polarimeter
Marrone, Daniel P.; Rao, Ramprasad
2008-01-01
We describe the Submillimeter Array (SMA) Polarimeter, a polarization converter and feed multiplexer installed on the SMA. The polarimeter uses narrow-band quarter-wave plates to generate circular polarization sensitivity from the linearly-polarized SMA feeds. The wave plates are mounted in rotation stages under computer control so that the polarization handedness of each antenna is rapidly selectable. Positioning of the wave plates is found to be highly repeatable, better than 0.2 degrees. A...
Hall, John Champlin; Martins, Guy Lawrence
2015-09-06
A method and apparatus for efficient manufacture, assembly and production of solar energy. In one aspect, the apparatus may include a number of modular solar receiver assemblies that may be separately manufactured, assembled and individually inserted into a solar collector array housing shaped to receive a plurality of solar receivers. The housing may include optical elements for focusing light onto the individual receivers, and a circuit for electrically connecting the solar receivers.
El-Ganainy, Ramy; Ge, Li; Khajavikhan, Mercedeh; Christodoulides, Demetrios
2015-01-01
We introduce the concept of supersymmetric laser arrays that consists of a main optical lattice and its superpartner structure, and we investigate the onset of their lasing oscillations. Due to the coupling of the two constituent lattices, their degenerate optical modes form doublets, while the extra mode associated with unbroken supersymmetry forms a singlet state. Singlet lasing can be achieved for a wide range of design parameters either by introducing stronger loss in the partner lattice ...
Navarro Contreras, Héctor Ángel
2010-01-01
Microphone arrays consist of multiple microphones functioning as a single directional input device: essentially, an acoustic antenna. Using sound propagation principles, the principal sound sources in an environment can be spatially located. Distinguishing sounds based on the spatial location of their source is achieved by filtering and combining the individual microphone signals. The location of the principal sounds sources may be determined dynamically by analyzing peaks i...
Seismometer array station processors
International Nuclear Information System (INIS)
A description is given of the design, construction and initial testing of two types of Seismometer Array Station Processor (SASP), one to work with data stored on magnetic tape in analogue form, the other with data in digital form. The purpose of a SASP is to detect the short period P waves recorded by a UK-type array of 20 seismometers and to edit these on to a a digital library tape or disc. The edited data are then processed to obtain a rough location for the source and to produce seismograms (after optimum processing) for analysis by a seismologist. SASPs are an important component in the scheme for monitoring underground explosions advocated by the UK in the Conference of the Committee on Disarmament. With digital input a SASP can operate at 30 times real time using a linear detection process and at 20 times real time using the log detector of Weichert. Although the log detector is slower, it has the advantage over the linear detector that signals with lower signal-to-noise ratio can be detected and spurious large amplitudes are less likely to produce a detection. It is recommended, therefore, that where possible array data should be recorded in digital form for input to a SASP and that the log detector of Weichert be used. Trial runs show that a SASP is capable of detecting signals down to signal-to-noise ratios of about two with very few false detections, and at mid-continental array sites it should be capable of detecting most, if not all, the signals with magnitude above msub(b) 4.5; the UK argues that, given a suitable network, it is realistic to hope that sources of this magnitude and above can be detected and identified by seismological means alone. (author)
Chow, Edward T.; Schatzel, Donald V.; Whitaker, William D.; Sterling, Thomas
2008-01-01
A Spaceborne Processor Array in Multifunctional Structure (SPAMS) can lower the total mass of the electronic and structural overhead of spacecraft, resulting in reduced launch costs, while increasing the science return through dynamic onboard computing. SPAMS integrates the multifunctional structure (MFS) and the Gilgamesh Memory, Intelligence, and Network Device (MIND) multi-core in-memory computer architecture into a single-system super-architecture. This transforms every inch of a spacecraft into a sharable, interconnected, smart computing element to increase computing performance while simultaneously reducing mass. The MIND in-memory architecture provides a foundation for high-performance, low-power, and fault-tolerant computing. The MIND chip has an internal structure that includes memory, processing, and communication functionality. The Gilgamesh is a scalable system comprising multiple MIND chips interconnected to operate as a single, tightly coupled, parallel computer. The array of MIND components shares a global, virtual name space for program variables and tasks that are allocated at run time to the distributed physical memory and processing resources. Individual processor- memory nodes can be activated or powered down at run time to provide active power management and to configure around faults. A SPAMS system is comprised of a distributed Gilgamesh array built into MFS, interfaces into instrument and communication subsystems, a mass storage interface, and a radiation-hardened flight computer.
Barnes, George H. (Inventor); Lundstrom, Stephen F. (Inventor); Shafer, Philip E. (Inventor)
1983-01-01
A high speed parallel array data processing architecture fashioned under a computational envelope approach includes a data base memory for secondary storage of programs and data, and a plurality of memory modules interconnected to a plurality of processing modules by a connection network of the Omega gender. Programs and data are fed from the data base memory to the plurality of memory modules and from hence the programs are fed through the connection network to the array of processors (one copy of each program for each processor). Execution of the programs occur with the processors operating normally quite independently of each other in a multiprocessing fashion. For data dependent operations and other suitable operations, all processors are instructed to finish one given task or program branch before all are instructed to proceed in parallel processing fashion on the next instruction. Even when functioning in the parallel processing mode however, the processors are not locked-step but execute their own copy of the program individually unless or until another overall processor array synchronization instruction is issued.
Synthetic Genetic Array Analysis.
Kuzmin, Elena; Costanzo, Michael; Andrews, Brenda; Boone, Charles
2016-01-01
Genetic interaction studies have been used to characterize unknown genes, assign membership in pathway and complex, and build a comprehensive functional map of a eukaryotic cell. Synthetic genetic array (SGA) methodology automates yeast genetic analysis and enables systematic mapping of genetic interactions. In its simplest form, SGA consists of a series of replica pinning steps that enable construction of haploid double mutants through automated mating and meiotic recombination. Using this method, a strain carrying a query mutation, such as a deletion allele of a nonessential gene or a conditional temperature-sensitive allele of an essential gene, can be crossed to an input array of yeast mutants, such as the complete set of approximately 5000 viable deletion mutants. The resulting output array of double mutants can be scored for genetic interactions based on estimates of cellular fitness derived from colony-size measurements. The SGA score method can be used to analyze large-scale data sets, whereas small-scale data sets can be analyzed using SGAtools, a simple web-based interface that includes all the necessary analysis steps for quantifying genetic interactions. PMID:27037072
Nanopillar Arrays on Semiconductor Membranes as Electron Emission Amplifiers
Qin, Hua; Kim, Hyun-Seok; Blick, Robert H.
2007-01-01
A new transmission-type electron multiplier was fabricated from silicon-on-insulator (SOI) material by integrating an array of one dimensional (1D) silicon nanopillars onto a two dimensional (2D) silicon membrane. Primary electrons are injected into the nanopillar-membrane system from the flat surface of the membrane, while electron emission from the other side is probed by an anode. The secondary electron yield (SEY) from nanopillars is found to be about 1.8 times that of plane silicon membr...
Compact collimated fiber optic array diagnostic for railgun plasma experiments
Energy Technology Data Exchange (ETDEWEB)
Tang, V; Solberg, J; Ferriera, T; Tully, L; Stephan, P
2008-10-02
We have developed and tested a compact collimated sixteen channel fiber optic array diagnostic for studying the light emission of railgun armature plasmas with {approx}mm spatial and sub-{micro}s temporal resolution. The design and operational details of the diagnostic are described. Plasma velocities, oscillation, and dimension data from the diagnostic for the Livermore Fixed Hybrid Armature experiment are presented and compared with 1-D simulations. The techniques and principles discussed allow the extension of the diagnostic to other railgun and related dense plasma experiments.
BISON, 1-D Burnup and Transport in Slab, Cylindrical, Spherical Geometry
International Nuclear Information System (INIS)
1 - Description of problem or function: BISON-1.5 solves the one- dimensional Boltzmann transport equation for neutron and gamma-rays and transmutation equations for fuel nuclides. 2 - Method of solution: In the transport calculation stage the one- dimensional Boltzmann transport equation is solved by the discrete ordinates method. In the burnup calculation stage, transmutation equations for fuel nuclides are solved by Bateman's method. The neutron flux obtained in the transport calculation stage is used to determine the transmutation rates in the burnup calculation stage. Both stages are repeated in tandem till the end of the burnup cycle. 3 - Restrictions on the complexity of the problem: A 42-group neutron and 21-group gamma-ray cross section library is prepared in the code package. Core storage for array variables is dynamically allocated by the code, so there are no restrictions on the size of each array
1D Measurement of Sodium Ion Flow in Hydrogel After a Bath Concentration Jump.
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
Fuel temperature estimation of MATRA code for SPERT-1D plate fuel during RIA
International Nuclear Information System (INIS)
In transient analysis, heat flux is not directly given but derived from heat conduction in fuel using heat source supplied by neutronics. The conduction in MATRA code computes internal temperature distributions within heat conducting material and the surface heat fluxes to adjacent fluid channels. In conduction, orthogonal collocation is employed to an approximate polynomial solution with residuals method. Typical subchannel codes developed to design the commercial LWR are mainly performed to validate on the rod type with ceramic fuel. On the contrary, there are few validations on the plate type with metal fuel. SPERT-1D test with a metal fuel of plate type generally used in the was to measure the fuel centerline and surface temperature during power transients by RIA. Validations of the plate type fuel temperature calculation of MATRA code are performed to compare the SPERT-1D test results using equal heat transfer coefficient model. Fuel model of MATRA code was estimated to compare the fuel centerline and surface temperature with the transient experimental results. For the sake of estimating a pool boiling using subchannel code, equal heat transfer coefficient model was developed. The main idea of the model substitutes the pool boiling condition to the equal forced convection heat transfer coefficient neglecting the detail flow condition
Fuel temperature estimation of MATRA code for SPERT-1D plate fuel during RIA
Energy Technology Data Exchange (ETDEWEB)
Kwon, Hyuk; Kim, S. J.; Seo, K. W.; Hwang, D. H. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)
2013-05-15
In transient analysis, heat flux is not directly given but derived from heat conduction in fuel using heat source supplied by neutronics. The conduction in MATRA code computes internal temperature distributions within heat conducting material and the surface heat fluxes to adjacent fluid channels. In conduction, orthogonal collocation is employed to an approximate polynomial solution with residuals method. Typical subchannel codes developed to design the commercial LWR are mainly performed to validate on the rod type with ceramic fuel. On the contrary, there are few validations on the plate type with metal fuel. SPERT-1D test with a metal fuel of plate type generally used in the was to measure the fuel centerline and surface temperature during power transients by RIA. Validations of the plate type fuel temperature calculation of MATRA code are performed to compare the SPERT-1D test results using equal heat transfer coefficient model. Fuel model of MATRA code was estimated to compare the fuel centerline and surface temperature with the transient experimental results. For the sake of estimating a pool boiling using subchannel code, equal heat transfer coefficient model was developed. The main idea of the model substitutes the pool boiling condition to the equal forced convection heat transfer coefficient neglecting the detail flow condition.
Directory of Open Access Journals (Sweden)
A. Gimelli
2012-01-01
Full Text Available The authors here extend a 0D-1D thermofluid dynamic simulation approach to describe the phenomena internal to the volumetric machines, reproducing pressure waves’ propagation in the ducts. This paper reports the first analysis of these phenomena in a reciprocating compressor. The first part presents a detailed experimental analysis of an open-type reciprocating compressor equipped with internal sensors. The second part describes a 0D-1D thermofluid dynamic simulation of the compressor. Comparison of computed and measured values of discharge mass flow rate shows a good agreement between results for compression ratio <5. Then, to improve the model fitting at higher pressures, a new scheme has been developed to predict the blow-by through the ring pack volumes. This model is based on a series of volumes and links which simulate the rings’ motions inside the grooves, while the ring dynamics are imposed using data from the literature about blow-by in internal combustion engines. The validation is obtained comparing experimental and computing data of the two cylinder engine blowby. After the validation, a new comparison of mass flow rate on the compressor shows a better fitting of the curves at higher compression ratio.
CD1d expression and invariant NKT cell responses in herpesvirus infections
Directory of Open Access Journals (Sweden)
Rusung eTan
2015-06-01
Full Text Available Invariant natural killer T (iNKT cells are a highly conserved subset of unconventional T lymphocytes that express a canonical, semi-invariant T cell receptor (TCR and surface markers shared with the natural killer cell lineage. iNKT cells recognize exogenous and endogenous glycolipid antigens restricted by non-polymorphic CD1d molecules, and are highly responsive to the prototypical agonist, α-galactosylceramide. Upon activation, iNKT cells rapidly coordinate signaling between innate and adaptive immune cells through the secretion of proinflammatory cytokines, leading to the maturation of antigen-presenting cells and expansion of antigen-specific CD4+ and CD8+ T cells. Because of their potent immunoregulatory properties, iNKT cells have been extensively studied and are known to play a pivotal role in mediating immune responses against microbial pathogens including viruses. Here, we review evidence that herpesviruses manipulate CD1d expression to escape iNKT cell surveillance and establish lifelong latency in humans. Collectively, published findings suggest that iNKT cells play critical roles in anti-herpesvirus immune responses and could be harnessed therapeutically to limit viral infection and viral-associated disease.
Assessment of a fast electro-optical shutter for 1D spontaneous Raman scattering in flames
Ajrouche, Hassan; Lo, Amath; Vervisch, Pierre; Cessou, Armelle
2015-07-01
A critical aspect of 1D single-shot spontaneous Raman scattering (SRS) experiments in turbulent flames is the need to ensure highly efficient detection associated with fast temporal gating to remove flame emission. Back-illuminated CCD cameras are remarkable for their high quantum efficiency, large dynamic range, good spatial resolution and low readout noise. However, their full-frame architecture makes these detectors difficult to use for SRS measurements in flame and requires the development of a high-speed shutter. The present work proposes a fast electro-optical shutter composed of a large aperture Pockels cell placed between two crossed polarizers, providing high-speed gating up to 500 ns. The throughput of the shutter and its spatial homogeneity are measured. The angular tolerance of the Pockels cell is determined and its suitability for 1D probing is assessed. Spectra acquired in a premixed methane-air flame show the capacity of the shutter to remove flame emission and increase the signal-to-noise ratio for major Raman species.
Screening masses in quenched (2+1)d Yang-Mills theory: universality from dynamics?
Energy Technology Data Exchange (ETDEWEB)
Frigori, Rafael B. [Universidade Tecnologica Federal do Parana (UTFPR), PR (Brazil)
2011-07-01
Full text: We have computed the spectrum of gluonic screening-masses in the scalar channel of quenched 3d Yang - Mills theory near the phase - transition. Our finite-temperature lattice simulations have been performed at the scaling region, using state-of- the-art techniques for thermalization and spectroscopy, which allows for thorough data extrapolations to thermodynamic limit. In addition no discretization effects were observed for the employed lattice sizes, which indicates that these results are still valid when taking the continuum limit of the theory. Ratios among mass-excitations with the same quantum numbers on the gauge theory, the 2d Ising model and the Lambda-phi-4 theory on the lattice are compared, resulting in a nice agreement with predictions from universality hypothesis. We have also compared the obtained mass ratios with predictions from a dynamical 'gauge-to-scalar mapping', recently proposed by M. Frasca to fit QCD Greens functions at deep IR in (3+1)d, to whom our data shows a nice universal agreement even in (2+1)d. (author)
IDENT 1D - a novel software tool for an easy identification of material constitutive parameters
International Nuclear Information System (INIS)
Non-linear finite element computations make use of very sophisticated constitutive equations for the description of materials behaviour. The first difficulty encountered by potential users is the gap existing between raw material characterisation on uniaxial specimens and the knowledge of the required equation's parameters. There are very few softwares for this particular task. IDENT 1D is a special software developed under Matlab language in our laboratory, which is able to provide a complete optimised parameters set for implemented models. The originality of IDENT 1D is that no initial estimation of the material parameters is requested of the user. Two main examples are described in this article: the LEMAITRE AND CHABOCHE (1990) creep law coupled with damage and a non unified cyclic law proposed by CONTESTI AND CAILLETAUD (1989) with a separation of plastic and viscous strain terms which is called DDI model. For both laws, the identification method is completely described. Each method is then applied to a set of experimental data. In both cases, the results of the parameters identification show a very good agreement with experimental data. (orig.)
1-D Air-snowpack modeling of atmospheric nitrous acid at South Pole during ANTCI 2003
Directory of Open Access Journals (Sweden)
W. Liao
2008-12-01
Full Text Available A 1-D air-snowpack model of HONO has been developed and constrained by observed chemistry and meteorology data. The 1-D model includes molecular diffusion and mechanical dispersion, windpumping in snow, gas phase to quasi-liquid layer phase HONO transfer and quasi-liquid layer nitrate and interstitial air HONO photolysis. Photolysis of nitrate is important as a dominant HONO source inside the snowpack, however, the observed HONO emission from the snowpack was triggered mainly by the equilibrium between quasi liquid layer nitrite and firn air HONO deep down the snow surface (i.e. 30 cm below snow surface. The high concentration of HONO in the firn air is subsequently transported above the snowpack by diffusion and windpumping. The model uncertainties come mainly from lack of measurements and the interpretation of the QLL properties based on the bulk snow measurements. One critical factor is the ionic strength of QLL nitrite, which is estimated here by the bulk snow pH, nitrite concentration, and QLL to bulk snow volume ratio.
1D self-assembly of chemisorbed thymine on Cu(110) driven by dispersion forces.
Temprano, I; Thomas, G; Haq, S; Dyer, M S; Latter, E G; Darling, G R; Uvdal, P; Raval, R
2015-03-14
Adsorption of thymine on a defined Cu(110) surface was studied using reflection-absorption infrared spectroscopy (RAIRS), temperature programmed desorption (TPD), and scanning tunnelling microscopy (STM). In addition, density functional theory (DFT) calculations were undertaken in order to further understand the energetics of adsorption and self-assembly. The combination of RAIRS, TPD, and DFT results indicates that an upright, three-point-bonded adsorption configuration is adopted by the deprotonated thymine at room temperature. DFT calculations show that the upright configuration adopted by individual molecules arises as a direct result of strong O-Cu and N-Cu bonds between the molecule and the surface. STM data reveal that this upright thymine motif self-assembles into 1D chains, which are surprisingly oriented along the open-packed [001] direction of the metal surface and orthogonal to the alignment of the functional groups that are normally implicated in H-bonding interactions. DFT modelling of this system reveals that the molecular organisation is actually driven by dispersion interactions, which cause a slight tilt of the molecule and provide the major driving force for assembly into dimers and 1D chains. The relative orientations and distances of neighbouring molecules are amenable for π-π stacking, suggesting that this is an important contributor in the self-assembly process. PMID:25770505
Ident 1D - a novel software tool for an easy identification of material constitutive parameters
International Nuclear Information System (INIS)
Non-linear finite element computations make use of very sophisticated constitutive equations for description of materials behaviour. The first difficulty encountered by potential users is the gap existing between raw material characterisation on uniaxial specimens and the knowledge of the required equation's parameters. There are very few software for this particular task. IDENT 1D is a special software developed under Matlab language in our laboratory, which is able to provide a complete optimised parameters set for implemented models. The originality of IDENT 1D is that no initial estimation of the material parameters is requested of the user. Two main examples are described in this article: the Lemaitre and Chaboche creep law coupled with damage and a non unified cyclic law proposed by Contesti and Cailletaud with a separation of plastic and viscous strain terms which is called DDI model. For both laws, the identification method is completely described. Each method is then applied to a set of experimental data. In both cases, the results of the parameters identification show a very good agreement with experimental data. (authors)
A Review of Swarm-Based 1D/2D Signal Processing
Directory of Open Access Journals (Sweden)
Horia Mihail Teodorescu
2012-10-01
Full Text Available While swarming behavior, widely encountered in nature, has recently sparked numerous models and interest in domains as optimization, data clustering, and control, their application to signal processing remains sporadic. In this paper I provide a unitary treatment and a review of former results obtained in signal filtering and enhancement using swarms. General equations are presented for these procedures and stability issues are considered, with examples. The paper overviews several swarming model I introduced in previous papers and provides new evidence of the applicability of these models in signal processing. In all the models for 1D signal processing, the key idea is that the swarm hunts a prey that impersonates the filtered signal. In the 2D models, the signal (image represents the “landscape” over which the swarm moves at a distance, while the swarm interacts with the signal (landscape. I provide and discuss details of the underlying theory of the models for processing time-domain signals and images. While this paper partly follows and summarizes previous papers, it nevertheless includes supplementary theoretical and algorithmic considerations and new results for both 1D and 2D signal processing. Although following either biological models or physical models in swarm algorithms is not generally accepted for technical applications, we prefer to emphasize the analogies established by our biomimetic approach with these two groups of models.
Performance studies on high pressure 1-D position sensitive neutron detectors
Indian Academy of Sciences (India)
S S Desai; A M Shaikh
2008-11-01
The powder diffractometer and Hi-Q diffractometer at Dhruva reactor make use of five identical 1-D position sensitive detectors (PSDs) to scan scattering angles in the range 3° to 140°. In order to improve the overall throughput of these spectrometers, it is planned to install a bank of 15 high-efficiency and high-resolution PSDs arranged in three layers with five PSDs in each layer. With each high pressure PSD (3He 10 bar + Kr 2 bar) showing the efficiency gain of 1.8 at 1.2 Å, detector bank is expected to show overall gain of 5.5 times the present detection efficiency and reduction in data collection time by equivalent factor. The 1-D PSDs are developed in batches of five, and are characterized so that all PSDs operate at uniform parameters such as position resolution, uniformity of efficiency and linearity of response. Position spectrum indicates the differential position resolution to be ∼ 1 mm and integral position resolution to be 3–4 mm. Broadening of position spectrum at the extreme end of sensitive length of PSD is analysed using fine shift of the beam. Dependence of position resolution and dynamic range of output pulse on the input impedance of pre-amplifier is also presented.
DISCOLORATION OF THE WETTED SURFACE IN THE 6.1D DISSOLVER
Energy Technology Data Exchange (ETDEWEB)
Rudisill, T.; Mickalonis, J.; Crapse, K.
2013-12-18
During a camera inspection of a failed coil in the 6.1D dissolver, an orange discoloration was observed on a portion of the dissolver wall and coils. At the request of H-Canyon Engineering, the inspection video of the dissolver was reviewed by SRNL to assess if the observed condition (a non-uniform, orange-colored substance on internal surfaces) was a result of corrosion. Although the dissolver vessel and coil corrode during dissolution operations, the high acid conditions are not consistent with the formation of ferrous oxides (i.e., orange/rust-colored corrosion products). In a subsequent investigation, SRNL performed dissolution experiments to determine if residues from the nylon bags used for Pu containment could have generated the orange discoloration following dissolution. When small pieces of a nylon bag were placed in boiling 8 M nitric acid solutions containing other components representative of the H-Canyon process, complete dissolution occurred almost immediately. No residues were obtained even when a nylon mass to volume ratio greater than 100 times the 6.1D dissolver value was used. Degradation products from the dissolution of nylon bags are not responsible for the discoloration observed in the dissolver.
Quasi-1D physics in metal-organic frameworks: MIL-47(V from first principles
Directory of Open Access Journals (Sweden)
Danny E. P. Vanpoucke
2014-10-01
Full Text Available The geometric and electronic structure of the MIL-47(V metal-organic framework (MOF is investigated by using ab initio density functional theory (DFT calculations. Special focus is placed on the relation between the spin configuration and the properties of the MOF. The ground state is found to be antiferromagnetic, with an equilibrium volume of 1554.70 Å3. The transition pressure of the pressure-induced large-pore-to-narrow-pore phase transition is calculated to be 82 MPa and 124 MPa for systems with ferromagnetic and antiferromagnetic chains, respectively. For a mixed system, the transition pressure is found to be a weighted average of the ferromagnetic and antiferromagnetic transition pressures. Mapping DFT energies onto a simple-spin Hamiltonian shows both the intra- and inter-chain coupling to be antiferromagnetic, with the latter coupling constant being two orders of magnitude smaller than the former, suggesting the MIL-47(V to present quasi-1D behavior. The electronic structure of the different spin configurations is investigated and it shows that the band gap position varies strongly with the spin configuration. The valence and conduction bands show a clear V d-character. In addition, these bands are flat in directions orthogonal to VO6 chains, while showing dispersion along the the direction of the VO6 chains, similar as for other quasi-1D materials.
International Nuclear Information System (INIS)
The effective potential of components of the curl of an antisymmetric tensor coupled to gravity in D dimensions is evaluated in a 1/D expansion. For large D, only highest-rank propagators contribute to leading order, while multiloop diagrams are suppressed by phase-space factors. Divergences are regulated by a cut-off LAMBDA, that we interpret as the mass-breaking scale of a larger theory that is finite. As an application we consider the bosonic sector of D=11, N=1 supergravity. If the full theory is finite, then LAMBDA is msub(SUSY): the scale below which the fermion sector decouples. For m9sub(SUSY)>1/akappa2, (kappa2: the D=11 Newton's coupling, a approx.= O(1)) the 11-dimensional symmetric vacuum is unstable under compactification. For m9sub(SUSY)2, it is metastable. To leading order in 1/D, all gauge dependence cancels identically, while ghosts as well as the graviton decouple. (author)
Numerical and experimental investigations of surface roughness in 1D photonic crystals
International Nuclear Information System (INIS)
We present numerical simulations as well as experimental investigations of 1D photonic crystals (PhC) with intentionally introduced surface roughness. An 'experimental simulation' of the roughness was created by gluing alumina powder to both sides of each alumina plate in an alumina-air structure. Transmission experiments were performed on this 1D PhC at microwave frequencies. A 'red-shift' of the band edges observed in experiment and simulation is explained by an increase of the effective thickness of the alumina layers as the surface roughness becomes stronger. The influence of the features of the roughness becomes visible in the simulations only at wavelengths short enough to be of the order of the dimensions of these features. Then, the band edges are smeared and the residual transmission in the band gaps is increased. We show that the main effect responsible for the smearing of the band edges is the scattering of the wave on roughness features. Even for very strong roughness (40% of the plate thickness) the band gaps are not destroyed completely.
Superdescendants of the D1D5 CFT and their dual 3-charge geometries
Energy Technology Data Exchange (ETDEWEB)
Giusto, Stefano [Dipartimento di Fisica ed Astronomia “Galileo Galilei”, Università di Padova,Via Marzolo 8, 35131 Padova (Italy); I.N.F.N. Sezione di Padova,Via Marzolo 8, 35131 Padova (Italy); Russo, Rodolfo [Centre for Research in String Theory, School of Physics and Astronomy,Queen Mary University of London, Mile End Road, London, E1 4NS (United Kingdom); Laboratoire de Physique Théorique de L’Ecole Normale Supérieure,24 rue Lhomond, 75231 Paris cedex (France)
2014-03-03
We describe how to obtain the gravity duals of semiclassical states in the D1-D5 CFT that are superdescendants of a class of RR ground states. On the gravity side, the configurations we construct are regular and asymptotically reproduce the 3-charge D1-D5-P black hole compactified on S{sup 1}×T{sup 4}. The geometries depend trivially on the T{sup 4} directions but non-trivially on the remaining 6D space. In the decoupling limit, they reduce to asymptotically AdS{sub 3}×S{sup 3}×T{sup 4} spaces that are dual to CFT states obtained by acting with (exponentials of) the operators of the superconformal algebra. As explicit examples, we generalise the solution first constructed in arXiv:1306.1745 and discuss another class of states that have a more complicated dual geometry. By using the free orbifold description of the CFT we calculate the average values for momentum and the angular momenta of these configurations. Finally we compare the CFT results with those obtained in the bulk from the asymptotically M{sup 1,4}×S{sup 1}×T{sup 4} region.
Wysocka-Żołopa, Monika; Winkler, Krzysztof
2015-12-01
Composites of polypyrrole and one-dimensional iridium complex crystals [(C2H5)4N]0.55[IrCl2(CO)2] were prepared by in situ two-step electrodeposition. Initially, iridium complex crystals were formed during [IrCl2(CO)2]- complex oxidation. Next, pyrrole was electropolymerized on the surface of the iridium needles. The morphology of the composite was investigated by scanning and transmission electron microscopy. At positive potentials, the iridium complex crystals and the polypyrrole were oxidized. In aprotic solvents, oxidation of the iridium complex crystals resulted in their dissolution. In water containing tetra(n-butyl)ammonium chlorides, the 1-D iridium complex crystals were reversibly oxidized. The product of the iridium complex oxidation remained on the electrode surface in crystalline form. The iridium complex needles significantly influenced the redox properties of the polymer. The polypyrrole involved electrode processes become more reversible in presence of crystals of iridium complex. The current of polypyrrole oxidation was higher compared to that of pure polypyrrole and the capacitance properties of the polymer were significantly enhanced. A specific capacitance as high as 590 F g-1 was obtained for a composite of polypyrrole and 1-D crystals of the iridium complex in water containing tetra(n-butyl)ammonium chloride. This value is approximately twice as high as the capacitance of the pure polymer deposited onto the electrode surface.
A mass-conservative finite volume predictor-corrector solution of the 1D Richards' equation
Lai, Wencong; Ogden, Fred L.
2015-04-01
Numerical solution of the Richards' equation (RE) in variably saturated soils continues to be a challenge due to its highly non-linear behavior. This is particularly true as soils approach saturation and the behavior of the fundamental partial differential equation changes from elliptic to parabolic. In this paper, a finite volume predictor-corrector method with adaptive time-stepping was developed to solve the 1D vertical RE. The numerical method was mass-conservative and non-iterative. In the predictor step, the pressure head-based form of the RE was solved using the cell-centered finite volume method and the pressure head was updated. In the corrector step, the soil water content was calculated by solving the mixed form RE. Five different schemes to evaluate the inter-cell hydraulic conductivity were investigated. The robustness and accuracy of the numerical model were demonstrated through simulation of experimental tests, including free drainage, field infiltration into wet and dry soils, and laboratory infiltration with falling water table. Numerical results were compared against laboratory measurements, simulation results from the Hydrus-1D program, or analytical solution when available. Results showed that the developed scheme is robust and accurate in simulating variably saturated flows with various boundary conditions. The arithmetic mean and Szymkiewicz's mean of inter-cell hydraulic conductivity performed better than other methods especially in the case of infiltration into very dry soil.
Bogoliubov coefficients for the twist operator in the D1D5 CFT
International Nuclear Information System (INIS)
The D1D5 CFT is a holographic dual of a near-extremal black hole in string theory. The interaction in this theory involves a twist operator which joins together different copies of a free CFT. Given a large number of D1 and D5 branes, the effective length of the circle on which the CFT lives is very large. We develop a technique to study the effect of the twist operator in the limit where the wavelengths of excitations are short compared to this effective length, which we call the ‘continuum limit’. The method uses Bogoliubov coefficients to compute the effect of the twist operator in this limit. For bosonic fields, we use the method to reproduce recent results describing the effect of the twist operator when it links together CFT copies with windings M and N, producing a copy of winding M+N. We also comment on possible generalizations of our results. The methods developed here may help in understanding the twist interaction at higher orders. This in turn should provide insight into the thermalization process in the D1D5 CFT, which gives a holographic description of black hole formation
Nylon 6,6 electrospun fibres reinforced by amino functionalised 1D and 2D carbon
International Nuclear Information System (INIS)
Nylon 6,6 electrospun nanocomposites were prepared and reinforced with 0.1, 0.5 and 1wt.% of 1D and 2D carbon. Both carbon nanotubes and graphene were functionalised with amino groups (f-CNT and f-Ge respectively). The morphology and graphitization changes of carbon nanomaterials were evaluated by transmission electron microscopy (TEM) and Raman spectroscopy; functional groups of modified nanomaterials was analysed by infrared spectroscopy. The mechanical response and the crystallinity of the fibres were measured by dynamical mechanical analysis, differential scanning calorimetry and wide angle x-ray diffraction. The morphology and dispersion of the nanomaterials in the nanofibres was studied by scanning electron microscopy and TEM. The storage modulus was improved by 118% for f-CNT and 116% for f-Ge. The mechanical response of the nanocomposites exhibited different behaviour upon loading of 1D and 2D carbon. This trend is consistent with the crystallinity of the nanofibres. This study showed f-CNT resulted in better mechanical properties at the lowest loading. On the other hand f-Ge showed improved reinforcing effect by increasing the filler loading. The two-dimensional structure of graphene was an important factor for the higher crystallinity in the electrospun nanofibres.
Zhang, Yingjie; Bhadbhade, Mohan; Karatchevtseva, Inna; Price, Jason R.; Liu, Hao; Zhang, Zhaoming; Kong, Linggen; Čejka, Jiří; Lu, Kim; Lumpkin, Gregory R.
2015-03-01
Three new coordination polymers of uranium(VI) with pyromellitic acid (H4btca) have been synthesized and structurally characterized. (ED)[(UO2)(btca)]·(DMSO)·3H2O (1) (ED=ethylenediammonium; DMSO=dimethylsulfoxide) has a lamellar structure with intercalation of ED and DMSO. (NH4)2[(UO2)6O2(OH)6(btca)]·~6H2O (2) has a 3D framework built from 7-fold coordinated uranyl trinuclear units and btca ligands with 1D diamond-shaped channels (~8.5 Å×~8.6 Å). [(UO2)2(H2O)(btca)]·4H2O (3) has a 3D network constructed by two types of 7-fold coordinated uranium polyhedron. The unique μ5-coordination mode of btca in 3 enables the formation of 1D olive-shaped large channels (~4.5 Å×~19 Å). Vibrational modes, thermal stabilities and fluorescence properties have been investigated.
Study of LCP based flexible patch antenna array
Ghaffar, Farhan A.
2012-07-01
Wrapping of a two element LCP based patch antenna array is studied in this work. For the first time, the designed array is bent in both E and H planes to observe the effect on the radiation and impedance performance of the antenna. The 38 GHz simulation results reveal better performance for H plane bending as compared to E plane bending. A 100 um thick substrate is used for the design which is best suited for flexible antenna applications. Gain variations of 1.1 dB and 1.4 dB are observed for the two orientations while a significantly increased impedance bandwidth of 3 % is obtained with H plane wrapping. The design is highly suitable for broadband micro-cellular backhaul applications. © 2012 IEEE.
Adipocyte-specific CD1d-deficiency mitigates diet-induced obesity and insulin resistance in mice.
Satoh, Masashi; Hoshino, Miyuki; Fujita, Koki; Iizuka, Misao; Fujii, Satoshi; Clingan, Christopher S; Van Kaer, Luc; Iwabuchi, Kazuya
2016-01-01
It has been shown that CD1d expression and glycolipid-reactive, CD1d-restricted NKT cells exacerbate the development of obesity and insulin resistance in mice. However, the relevant CD1d-expressing cells that influence the effects of NKT cells on the progression of obesity remain incompletely defined. In this study, we have demonstrated that 3T3-L1 adipocytes can present endogenous ligands to NKT cells, leading to IFN-γ production, which in turn, stimulated 3T3-L1 adipocytes to enhance expression of CD1d and CCL2, and decrease expression of adiponectin. Furthermore, adipocyte-specific CD1d deletion decreased the size of the visceral adipose tissue mass and enhanced insulin sensitivity in mice fed a high-fat diet (HFD). Accordingly, NKT cells were less activated, IFN-γ production was significantly reduced, and levels of adiponectin were increased in these animals as compared with control mice on HFD. Importantly, macrophage recruitment into the adipose tissue of adipocyte-specific CD1d-deficient mice was significantly blunted. These findings indicate that interactions between NKT cells and CD1d-expressing adipocytes producing endogenous NKT cell ligands play a critical role in the induction of inflammation and functional modulation of adipose tissue that leads to obesity. PMID:27329323
Depotentiation in the dentate gyrus of freely moving rats is modulated by D1/D5 dopamine receptors.
Kulla, A; Manahan-Vaughan, D
2000-06-01
Hippocampal depotentiation comprises a reversal of tetanization- induced long-term potentiation (LTP) which occurs following low-frequency stimulation. In the CA1 region, it has been reported that agonist activation of D1/D5 dopamine receptors enhances LTP expression and inhibits depotentiation. The role of these receptors in synaptic plasticity in the dentate gyrus (DG) has not been characterized. This study therefore investigated the role of D1/D5 receptors in LTP and depotentiation in the DG of freely moving rats. Male Wistar rats underwent chronic implantation of a recording electrode in the DG granule cell layer, a bipolar stimulating electrode in the medial perforant path and a cannula in the ipsilateral cerebral ventricle (to enable drug administration). The D1/D5 agonist Chloro-PB dose-dependently inhibited depotentation in the DG. This effect was prevented by the D1/D5 antagonist SCH 23390. Neither D1/D5 agonist nor antagonist had an effect on LTP expression or basal synaptic transmission. These results highlight differences between D1/D5 receptor-involvement in LTP and depotentiation in the CA1 region and DG, and indicate that whereas D1/D5 receptor activation may not be a critical factor in LTP induction in the DG, a differential role for these receptors in the expression of depotentiation, in this hippocampal subfield, may exist. PMID:10859139
Lysophospholipid presentation by CD1d and recognition by a human Natural Killer T-cell receptor
Energy Technology Data Exchange (ETDEWEB)
López-Sagaseta, Jacinto; Sibener, Leah V.; Kung, Jennifer E.; Gumperz, Jenny; Adams, Erin J. (UC); (UW-MED)
2014-10-02
Invariant Natural Killer T (iNKT) cells use highly restricted {alpha}{beta} T cell receptors (TCRs) to probe the repertoire of lipids presented by CD1d molecules. Here, we describe our studies of lysophosphatidylcholine (LPC) presentation by human CD1d and its recognition by a native, LPC-specific iNKT TCR. Human CD1d presenting LPC adopts an altered conformation from that of CD1d presenting glycolipid antigens, with a shifted {alpha}1 helix resulting in an open A pocket. Binding of the iNKT TCR requires a 7-{angstrom} displacement of the LPC headgroup but stabilizes the CD1d-LPC complex in a closed conformation. The iNKT TCR CDR loop footprint on CD1d-LPC is anchored by the conserved positioning of the CDR3{alpha} loop, whereas the remaining CDR loops are shifted, due in part to amino-acid differences in the CDR3{beta} and J{beta} segment used by this iNKT TCR. These findings provide insight into how lysophospholipids are presented by human CD1d molecules and how this complex is recognized by some, but not all, human iNKT cells.
Full Waveform 3D Synthetic Seismic Algorithm for 1D Layered Anelastic Models
Schwaiger, H. F.; Aldridge, D. F.; Haney, M. M.
2007-12-01
Numerical calculation of synthetic seismograms for 1D layered earth models remains a significant aspect of amplitude-offset investigations, surface wave studies, microseismic event location approaches, and reflection interpretation or inversion processes. Compared to 3D finite-difference algorithms, memory demand and execution time are greatly reduced, enabling rapid generation of seismic data within workstation or laptop computational environments. We have developed a frequency-wavenumber forward modeling algorithm adapted to realistic 1D geologic media, for the purpose of calculating seismograms accurately and efficiently. The earth model consists of N layers bounded by two halfspaces. Each layer/halfspace is a homogeneous and isotropic anelastic (attenuative and dispersive) solid, characterized by a rectangular relaxation spectrum of absorption mechanisms. Compressional and shear phase speeds and quality factors are specified at a particular reference frequency. Solution methodology involves 3D Fourier transforming the three coupled, second- order, integro-differential equations for particle displacements to the frequency-horizontal wavenumber domain. An analytic solution of the resulting ordinary differential system is obtained. Imposition of welded interface conditions (continuity of displacement and stress) at all interfaces, as well as radiation conditions in the two halfspaces, yields a system of 6(N+1) linear algebraic equations for the coefficients in the ODE solution. An optimized inverse 2D Fourier transform to the space domain gives the seismic wavefield on a horizontal plane. Finally, three-component seismograms are obtained by accumulating frequency spectra at designated receiver positions on this plane, followed by a 1D inverse FFT from angular frequency ω to time. Stress-free conditions may be applied at the top or bottom interfaces, and seismic waves are initiated by force or moment density sources. Examples reveal that including attenuation
Higher-order local and non-local correlations for 1D strongly interacting Bose gas
Nandani, EJKP; Römer, Rudolf A.; Tan, Shina; Guan, Xi-Wen
2016-05-01
The correlation function is an important quantity in the physics of ultracold quantum gases because it provides information about the quantum many-body wave function beyond the simple density profile. In this paper we first study the M-body local correlation functions, g M , of the one-dimensional (1D) strongly repulsive Bose gas within the Lieb–Liniger model using the analytical method proposed by Gangardt and Shlyapnikov (2003 Phys. Rev. Lett. 90 010401; 2003 New J. Phys. 5 79). In the strong repulsion regime the 1D Bose gas at low temperatures is equivalent to a gas of ideal particles obeying the non-mutual generalized exclusion statistics with a statistical parameter α =1-2/γ , i.e. the quasimomenta of N strongly interacting bosons map to the momenta of N free fermions via {k}i≈ α {k}iF with i=1,\\ldots ,N. Here γ is the dimensionless interaction strength within the Lieb–Liniger model. We rigorously prove that such a statistical parameter α solely determines the sub-leading order contribution to the M-body local correlation function of the gas at strong but finite interaction strengths. We explicitly calculate the correlation functions g M in terms of γ and α at zero, low, and intermediate temperatures. For M = 2 and 3 our results reproduce the known expressions for g 2 and g 3 with sub-leading terms (see for instance (Vadim et al 2006 Phys. Rev. A 73 051604(R); Kormos et al 2009 Phys. Rev. Lett. 103 210404; Wang et al 2013 Phys. Rev. A 87 043634). We also express the leading order of the short distance non-local correlation functions of the strongly repulsive Bose gas in terms of the wave function of M bosons at zero collision energy and zero total momentum. Here {{\\Psi }}(x) is the boson annihilation operator. These general formulas of the higher-order local and non-local correlation functions of the 1D Bose gas provide new insights into the many-body physics.
Assessing the impact of different sources of topographic data on 1-D hydraulic modelling of floods
Ali, A. Md; Solomatine, D. P.; Di Baldassarre, G.
2015-01-01
Topographic data, such as digital elevation models (DEMs), are essential input in flood inundation modelling. DEMs can be derived from several sources either through remote sensing techniques (spaceborne or airborne imagery) or from traditional methods (ground survey). The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), the Shuttle Radar Topography Mission (SRTM), the light detection and ranging (lidar), and topographic contour maps are some of the most commonly used sources of data for DEMs. These DEMs are characterized by different precision and accuracy. On the one hand, the spatial resolution of low-cost DEMs from satellite imagery, such as ASTER and SRTM, is rather coarse (around 30 to 90 m). On the other hand, the lidar technique is able to produce high-resolution DEMs (at around 1 m), but at a much higher cost. Lastly, contour mapping based on ground survey is time consuming, particularly for higher scales, and may not be possible for some remote areas. The use of these different sources of DEM obviously affects the results of flood inundation models. This paper shows and compares a number of 1-D hydraulic models developed using HEC-RAS as model code and the aforementioned sources of DEM as geometric input. To test model selection, the outcomes of the 1-D models were also compared, in terms of flood water levels, to the results of 2-D models (LISFLOOD-FP). The study was carried out on a reach of the Johor River, in Malaysia. The effect of the different sources of DEMs (and different resolutions) was investigated by considering the performance of the hydraulic models in simulating flood water levels as well as inundation maps. The outcomes of our study show that the use of different DEMs has serious implications to the results of hydraulic models. The outcomes also indicate that the loss of model accuracy due to re-sampling the highest resolution DEM (i.e. lidar 1 m) to lower resolution is much less than the loss of model accuracy due
Structural and population-based evaluations of TBC1D1 p.Arg125Trp.
Directory of Open Access Journals (Sweden)
Tom G Richardson
Full Text Available Obesity is now a leading cause of preventable death in the industrialised world. Understanding its genetic influences can enhance insight into molecular pathogenesis and potential therapeutic targets. A non-synonymous polymorphism (rs35859249, p.Arg125Trp in the N-terminal TBC1D1 phosphotyrosine-binding (PTB domain has shown a replicated association with familial obesity in women. We investigated these findings in the Avon Longitudinal Study of Parents and Children (ALSPAC, a large European birth cohort of mothers and offspring, and by generating a predicted model of the structure of this domain. Structural prediction involved the use of three separate algorithms; Robetta, HHpred/MODELLER and I-TASSER. We used the transmission disequilibrium test (TDT to investigate familial association in the ALSPAC study cohort (N = 2,292 mother-offspring pairs. Linear regression models were used to examine the association of genotype with mean measurements of adiposity (Body Mass Index (BMI, waist circumference and Dual-energy X-ray absorptiometry (DXA assessed fat mass, and logistic regression was used to examine the association with odds of obesity. Modelling showed that the R125W mutation occurs in a location of the TBC1D1 PTB domain that is predicted to have a function in a putative protein:protein interaction. We did not detect an association between R125W and BMI (mean per allele difference 0.27 kg/m(2 (95% Confidence Interval: 0.00, 0.53 P = 0.05 or obesity (odds ratio 1.01 (95% Confidence Interval: 0.77, 1.31, P = 0.96 in offspring after adjusting for multiple comparisons. Furthermore, there was no evidence to suggest that there was familial association between R125W and obesity (χ(2 = 0.06, P = 0.80. Our analysis suggests that R125W in TBC1D1 plays a role in the binding of an effector protein, but we find no evidence that the R125W variant is related to mean BMI or odds of obesity in a general population sample.
Chamberlain, Neil; Zawadzki, Mark; Sadowy, Greg; Oakes, Eric; Brown, Kyle; Hodges, Richard
2009-01-01
This paper describes the development of a patch antenna array for an L-band repeat-pass interferometric synthetic aperture radar (InSAR) instrument that is to be flown on an unmanned aerial vehicle (UAV). The antenna operates at a center frequency of 1.2575 GHz and with a bandwidth of 80 MHz, consistent with a number of radar instruments that JPL has previously flown. The antenna is designed to radiate orthogonal linear polarizations in order to facilitate fully-polarimetric measurements. Beam-pointing requirements for repeat-pass SAR interferometry necessitate electronic scanning in azimuth over a range of -20degrees in order to compensate for aircraft yaw. Beam-steering is accomplished by transmit/receive (T/R) modules and a beamforming network implemented in a stripline circuit board. This paper, while providing an overview of phased array architecture, focuses on the electromagnetic design of the antenna tiles and associated interconnects. An important aspect of the design of this antenna is that it has an amplitude taper of 10dB in the elevation direction. This is to reduce multipath reflections from the wing that would otherwise be detrimental to interferometric radar measurements. This taper is provided by coupling networks in the interconnect circuits as opposed to attenuating the output of the T/R modules. Details are given of material choices and fabrication techniques that meet the demanding environmental conditions that the antenna must operate in. Predicted array performance is reported in terms of co-polarized and crosspolarized far-field antenna patterns, and also in terms of active reflection coefficient.
Directory of Open Access Journals (Sweden)
José Alexandre de França
2011-06-01
Full Text Available Na visão computacional, a calibração de câmeras é um processo necessário quando deseja-se recuperar informações como, por exemplo, ângulos e distâncias. O presente trabalho trata do problema de calibração de câmeras com gabaritos de uma única dimensão. Atualmente, tal problema só tem solução se forem impostas restrições ao movimento do gabarito ou se alguns parâmetros das câmeras já sejam previamente conhecidos. Contudo, demonstra-se que uma abordagem diferente pode ser aplicada se, ao invés de uma única câmera, um conjunto binocular for considerado. Nesse caso, a calibração é possível com um gabarito 1D que realiza um deslocamento desconhecido e sem restrições, mesmo sem nenhuma informação prévia a respeito das câmeras. Tal método baseia-se na estimação de uma transformação que, após a estimação da matriz fundamental do sistema, permite atualizar uma calibração projetiva para uma calibração euclidiana. Experimentos em imagens reais e sintéticas validam o novo método e mostram que a sua exatidão é comparável a de outros métodos clássicos de calibração, já bem conhecidos na literatura.In computer vision, the camera calibration is a process needed when the recovery of some information, such as angles and distances, is desired. The present work deals with the problem of camera calibration using one-dimensional patterns. Nowadays, this problem only has a solution if some restrictions to the pattern's movement are imposed or if some angles of the cameras are known in advance. However, a different approach can be applied if, instead of only one camera, a stereo system is considered. In that case, the calibration is possible with a one-dimensional pattern that executes an unknown and unrestricted movement, even without any previous information concerning the cameras. Such method is based on the estimation of a transform which, after the estimation of the system's fundamental matrix, allows
Rudolf, Rüdiger; Fortin, Dominique
1995-01-01
An $n\\times n$ matrix $C$ is called a {\\em weak Monge\\/} matrix iff $c_{ii}+c_{rs}\\le c_{is}+c_{ri}$ for all $1\\le i\\le r,s\\le n$. It is well known that the classical linear assignment problem is optimally solved by the identity permutation if the underlying cost-matrix fulfills the weak Monge property. In this paper we introduce higher dimensional weak Monge arrays and prove that higher dimensional axial assignment problems can be solved efficiently if the cost-structure is a higher dimensio...
Rawlings, Steve
2011-01-01
We review the current status of the Square Kilometre Array (SKA) by outlining the science drivers for its Phase-1 (SKA1) and setting out the timeline for the key decisions and milestones on the way to the planned start of its construction in 2016. We explain how Phase-2 SKA (SKA2) will transform the research scope of the SKA infrastructure, placing it amongst the great astronomical observatories and survey instruments of the future, and opening up new areas of discovery, many beyond the confines of conventional astronomy.
Institute of Scientific and Technical Information of China (English)
无
2009-01-01
一个月前佳能刚刚发布了APS-C规格旗舰单反EOS 7D，一个月后，佳能再次为我们带来了惊喜，全球同步发布采用APS-H规格的高端数码单反——EOS-1D Mark Ⅳ。作为2007年5月发布的EOS-1D Mark Ⅲ的继任机型，新推出的EOS-1D Mark Ⅳ采用全新的CMOS感光元件。
Institute of Scientific and Technical Information of China (English)
无
2010-01-01
日前，佳能（中国）有限公司发布面向专业摄影师的数码单反相机EOS-1D Mark IV。EOS-1D Mark IV为EOS-1D／1Ds系列的第八款产品，是在新闻报道和体育摄影领域广受专业摄影师好评的EOS-1D Mark Ⅲ后继机型。
1 d calculations on transport, neutral injection heating and ignition control in ZEPHYR
International Nuclear Information System (INIS)
1 - d transport calculations and particle trajectory calculations for neutral injection in Zephyr show that without impurity radiation losses a heating power of 20 MW and a pulse length of 1 s should be sufficient to reach ignition in Zephyr (average densities in the compressed stage between 2 and 4.5 x 1014 cm-3). The injection system should have an acceleration voltage of 160 keV; lower energy neutrals require higher heating powers. Heating of the plasma in the compressed stage requires neutral particle energies of > approx. 250 keV. Active burn control of the nearly ignited plasma is possible with heating powers of about 1 MW and response times of the feedback system smaller than 200 ms. (orig.) 891 HT/orig. 892 HIS
Analytical solution for 1D consolidation of unsaturated soil with mixed boundary condition
Institute of Scientific and Technical Information of China (English)
Zhen-dong SHAN; Dao-sheng LING; Hao-jiang DING
2013-01-01
Based on consolidation equations proposed for unsaturated soil,an analytical solution for 1D consolidation of an unsaturated single-layer soil with nonhomogeneous mixed boundary condition is developed.The mixed boundary condition can be used for special applications,such as tests occur in laboratory.The analytical solution is obtained by assuming all material parameters remain constant during consolidation.In the derivation of the analytical solution,the nonhomogeneous boundary condition is first transformed into a homogeneous boundary condition.Then,the eigenfunction and eigenvalue are derived according to the consolidation equations and the new boundary condition.Finally,using the method of undetermined coefficients and the orthogonal relation of the eigenfunction,the analytical solution for the new boundary condition is obtained.The present method is applicable to various types of boundary conditions.Several numerical examples are provided to investigate the consolidation behavior of an unsaturated single-layer soil with mixed boundary condition.
International Nuclear Information System (INIS)
MOL1D is a FORTRAN subroutine package for the method of lines solution for systems of initial-boundary-value partial differential equations in one space dimension. Using the package, a programer with limited experience in numerical analysis can accurately solve linear and nonlinear hyperbolic equations with or without discontinuities, linear and nonlinear parabolic equations (including those arising in reaction-diffusion equations), and elliptic boundary-value problems when posed as the stable time-independent solution of a parabolic equation. Systems are handled as easily as single equations, and a wide variety of boundary conditions can be accommodated, including most that arise in applications. The major advantage of the package is that initial-value problems can be solved accurately with a minimum of programing effort and with moderate computer cost. 4 figures, 1 table
Fluid friction and wall viscosity of the 1D blood flow model
Wang, Xiao-Fei; Matsukawa, Mami; Ghigo, Arthur; Lagrée, Pierre-Yves; Fullana, Jose-Maria
2015-01-01
We study the behavior of the pulse waves of water into a flexible tube for application to blood flow simulations. In pulse waves both fluid friction and wall viscosity are damping factors, and difficult to evaluate separately. In this paper, the coefficients of fluid friction and wall viscosity are estimated by fitting a nonlinear 1D flow model to experimental data. In the experimental setup, a distensible tube is connected to a piston pump at one end and closed at another end. The pressure and wall displacements are measured simultaneously. A good agreement between model predictions and experiments was achieved. For amplitude decrease, the effect of wall viscosity on the pulse wave has been shown as important as that of fluid viscosity.
International Nuclear Information System (INIS)
The quantum dynamics problem for a 1D chain consisting of 2N + 1 sites (N ≫ 1) with the interaction of nearest neighbors and an impurity site at the middle differing in energy and in coupling constant from the sites of the remaining chain is solved analytically. The initial excitation of the impurity is accompanied by the propagation of excitation over the chain sites and with the emergence of Loschmidt echo (partial restoration of the impurity site population) in the recurrence cycles with a period proportional to N. The echo consists of the main (most intense) component modulated by damped oscillations. The intensity of oscillations increases with increasing cycle number and matrix element C of the interaction of the impurity site n = 0 with sites n = ±1 (0 2 fragments and predicts the possibility of a nondissipative energy transfer between reaction centers associated with such chains.
Staggered grid leap-frog scheme for the (2+1)D Dirac equation
Hammer, René; Pötz, Walter
2014-01-01
A numerical scheme utilizing a grid which is staggered in both space and time is proposed for the numerical solution of the (2+1)D Dirac equation in the presence of an external electromagnetic potential. It preserves the linear dispersion relation of the free Weyl equation for wave vectors aligned with the grid and facilitates the implementation of open (absorbing) boundary conditions via an imaginary potential term. This explicit scheme has second order accuracy in space and time. A functional for the norm is derived and shown to be conserved. Stability conditions are derived. Several numerical examples, ranging from generic to specific to textured topological insulator surfaces, demonstrate the properties of the scheme which can handle general electromagnetic potential landscapes.
Directed electromagnetic wave propagation in 1D metamaterial: Projecting operators method
Ampilogov, Dmitrii; Leble, Sergey
2016-07-01
We consider a boundary problem for 1D electrodynamics modeling of a pulse propagation in a metamaterial medium. We build and apply projecting operators to a Maxwell system in time domain that allows to split the linear propagation problem to directed waves for a material relations with general dispersion. Matrix elements of the projectors act as convolution integral operators. For a weak nonlinearity we generalize the linear results still for arbitrary dispersion and derive the system of interacting right/left waves with combined (hybrid) amplitudes. The result is specified for the popular metamaterial model with Drude formula for both permittivity and permeability coefficients. We also discuss and investigate stationary solutions of the system related to some boundary regimes.
Initial Stage of the Microwave Ionization Wave Within a 1D Model
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.
Classification of phases of 1D spin chains with commuting Hamiltonians
Beigi, Salman
2011-01-01
We consider the class of spin Hamiltonians on a 1D chain with periodic boundary conditions that are (i) translational invariant, (ii) commuting and (iii) scale invariant, where by the latter we mean that the ground state degeneracy is independent of the system size. We show that the ground state degeneracy is the only parameter that determines the phases of these Hamiltonians. We then characterize the low energy excitations by first making the assumption that there is no excitation of unit energy, and consequently show that all elementary excitations (of energy 2) come from the action of some string-type operator on the ground state which creates two quasi-particle excitations at the endpoints of the string. Our main tool in this paper is the idea of Bravyi and Vyalyi (2003) in using the representation theory of finite dimensional C*-algebras to study commuting Hamiltonians.
Directory of Open Access Journals (Sweden)
K. R. Santhi
2008-01-01
Full Text Available Digital filters have found their way into many products from every day consumer items such as mobile phones to advanced maritime and military communications and avionics systems. Design of digital filters faces two fundamental problems, their stability and synthesis. Recursive filters have more stability problems than nonrecursive filters. Stability of a filter can be determined by the location of the zero valued region of the denominator polynomial of its transfer function. Stability of recursive filters has been studied by many researchers for the past three decades. Several theorems on stability testing and stabilizing recursive digital filters have been already proposed. We present a new approach to test the stability problem of the one-dimensional (1-D recursive digital filters using Lagrange Multipliers. This method not only tests the stability of recursive digital filters, but also provides the stable version of the filter's transfer function if found to be unstable.
Development of input structure software for MARS 1D-3D graphic user interface
International Nuclear Information System (INIS)
A user-friendly Input Software for MARS 1D-3D GUI called MARA (MARS Adjunct Reactor Assembler) has been developed. Extension of the current MARA to the overall input system for MARS will result in an integrated commercial GUI comparable to those for computational analysis codes ANSYS, ABAQUS, FLUENT and CFX. MARA will help accelerate marketing of MARS and other potential system analysis codes to developing countries in Southeast Asia planning to put nuclear power in their electrical grids. MARS code and associated developmental technology are in the process of being disseminated to twenty-two organizations spanning the industry, academia and laboratories across the country. MARA will find its way to practical applications in a variety of engineering problems
Study of phase space structures in driven 1D Vlasov poisson model
International Nuclear Information System (INIS)
Electrostatic waves in a collisionless, unmagnetized plasma are known to interact with particles that stream with velocities close to the wave phase speed to produce damping effects, particle trapping and interesting nonlinear coherent structures. For example, it is well known that if the initial amplitude of the wave is large enough, the damping effects can be overcome to form BGK structures. In the present work, we consider a 1D driven Vlasov-Poisson plasma model. It is demonstrated that by a careful choice of drive phase and for drive amplitudes smaller than or comparable to the linear limit, it is possible to generate surprisingly large amplitude coherent structures in phase space. This and other details will be presented. (author)
Magnetic Reversal and Relaxation in a Quasi-1D Fractal Cluster Glass
Etzkorn, S. J.; Hibbs, Wendy; Miller, Joel S.; Epstein, A. J.
2003-03-01
The magnetic reversal of the quasi-1D organic-based magnet [MnTPP]^+[TCNE]^- otx(1,3-C_6H_4Cl_2) (TPP is tetraphenylporphyrin dianion, TCNE is tetracyanoethylene, x ˜ 2) is explored using both static and dynamic measurements. A time dependent shift is observed in the bifurcation point of the field-cooled and zero-field-cooled magnetization as a result of long time relaxation above the spin glass transition. Hysteresis measurements recorded with different applied magnetic field sweep rates show time dependent effects above the spin glass transition temperature. Below the transition temperature collective behavior in magnetic reversal is observed. The temperature dependence of the coercive field is linear below the glass transition suggesting the energy landscape is dominated by a single, temperature independent energy barrier. The results are examined in the context of an anisotropic fractal cluster model.
Transferable Integrated Optical SU8 Devices: From Micronic Waveguides to 1D-Nanostructures
Directory of Open Access Journals (Sweden)
Nolwenn Huby
2015-04-01
Full Text Available We report on optical components for integrated optics applications at the micro- and nanoscale. Versatile shapes and dimensions are achievable due to the liquid phase processability of SU8 resist. On the one hand, by adjusting the UV-lithography process, waveguiding structures are patterned and released from their original substrate. They can be replaced on any other substrate and also immerged in liquid wherein they still show off efficient light confinement. On the other hand, filled and hollow 1D-nanostructures are achievable by the wetting template method. By exploiting the large range of available SU8 viscosities, nanowires of diameter ranging between 50 nm and 240 nm, as well as nanotubes of controllable wall thickness are presented. Optical injection, propagation, and coupling in such nanostructures are relevant for highly integrated devices.
Quantum propagation and confinement in 1D systems using the transfer-matrix method
Pujol, Olivier; Carles, Robert; Pérez, José-Philippe
2014-05-01
The aim of this article is to provide some Matlab scripts to the teaching community in quantum physics. The scripts are based on the transfer-matrix formalism and offer a very efficient and versatile tool to solve problems of a physical object (electron, proton, neutron, etc) with one-dimensional (1D) stationary potential energy. Resonant tunnelling through a multiple-barrier or confinement in wells of various shapes is particularly analysed. The results are quantitatively discussed with semiconductor heterostructures, harmonic and anharmonic molecular vibrations, or neutrons in a gravity field. Scripts and other examples (hydrogen-like ions and transmission by a smooth variation of potential energy) are available freely at http://www-loa.univ-lille1.fr/˜pujol in three languages: English, French and Spanish.
A density-functional approach to fermionization in the 1D Bose gas
International Nuclear Information System (INIS)
A time-dependent Kohn-Sham scheme for 1D bosons with contact interaction is derived based on a model of spinor fermions. This model is specifically designed for the study of the strong interaction regime close to the Tonks gas. It allows us to treat the transition from the strongly interacting Tonks-Girardeau to the weakly interacting quasicondensate regime and provides an intuitive picture of the extent of fermionization in the system. An adiabatic local-density approximation is devised for the study of time-dependent processes. This scheme is shown to yield not only accurate ground-state properties but also overall features of the elementary excitation spectrum, which is described exactly in the Tonks-gas limit
Hamiltonian formalism for N=1, D=10 Yang--Mills coupled supergravity
International Nuclear Information System (INIS)
The canonical convariant formalism for N=1 D=10 matter-coupled supergravity is constructed and applied in both cases, when the Lagrangian density contains linear terms in the Riemann curvature, or the quadratic one. When in this coupled system the canonical formalism for higher curvature supergravities is considered, it is possible to show that the propagation torsion mechanism takes place. Starting from the first-order formalism with the Hamiltonian that contains a finite number of terms including higher curvature ones, the nonpolynomial structure of the second-order formalism of the supersymmetric transformation rules, as well as of the rheonomic equation, can be shown. This fact allows us to relate the higher curvature Hamiltonian formalism with the massless sector of effective superstring theories. copyright 1989 Academic Press, Inc
Dynamical properties of spin and subbands populations in 1D quantum wire
Vaseghi, B.; Khordad, R.; Golshan, M. M.
2006-10-01
In this paper we study the spin and subbands populations, as functions of time, for electrons in a quasi-1D quantum wire, with spin-orbit coupling (SOC), to which a perpendicular magnetic field is applied. The system is governed by the Hamiltonian which, in the strong magnetic field limit, resembles the Jaynes-Cummings model (JCM) in quantum optics (QO). Using a procedure similar to that in QO, we explicitly present the time-evolution operator, thereby calculating the spin states and subbands populations as functions of time. We show that the populations exhibit oscillations, depending on the interaction parameters, scale lengths and, particularly, the initial states of the system. Specifically, if the electrons are initially prepared in a maximal coherent superposition of spin states, the expectation values periodically collapse and revive. The collapse-revivals are most profound for the spin along the magnetic field and subbands populations.
An anti-symmetric exclusion process for two particles on an infinite 1D lattice
International Nuclear Information System (INIS)
A system of two biased, mutually exclusive random walkers on an infinite 1D lattice is studied whereby the intrinsic bias of one particle is equal and opposite to that of the other. The propagator for this system is solved exactly and expressions for the mean displacement and mean square displacement (MSD) are found. Depending on the nature of the intrinsic bias, the system’s behaviour displays two regimes, characterised by (i) the particles moving towards each other and (ii) away from each other, both qualitatively different from the case of no bias. The continuous-space limit of the propagator is found and is shown to solve a Fokker–Planck equation for two biased, mutually exclusive Brownian particles with equal and opposite drift velocity. Connections to territorial dynamics in animal populations are discussed. (paper)
An anti-symmetric exclusion process for two particles on an infinite 1D lattice
Energy Technology Data Exchange (ETDEWEB)
Potts, J R; Giuggioli, L [Bristol Centre for Complexity Sciences, University of Bristol, Bristol (United Kingdom); Harris, S, E-mail: jonathan.potts.08@bris.ac.uk [School of Biological Sciences, University of Bristol, Bristol (United Kingdom)
2011-12-02
A system of two biased, mutually exclusive random walkers on an infinite 1D lattice is studied whereby the intrinsic bias of one particle is equal and opposite to that of the other. The propagator for this system is solved exactly and expressions for the mean displacement and mean square displacement (MSD) are found. Depending on the nature of the intrinsic bias, the system's behaviour displays two regimes, characterised by (i) the particles moving towards each other and (ii) away from each other, both qualitatively different from the case of no bias. The continuous-space limit of the propagator is found and is shown to solve a Fokker-Planck equation for two biased, mutually exclusive Brownian particles with equal and opposite drift velocity. Connections to territorial dynamics in animal populations are discussed. (paper)
An anti-symmetric exclusion process for two particles on an infinite 1D lattice
Potts, J. R.; Harris, S.; Giuggioli, L.
2011-12-01
A system of two biased, mutually exclusive random walkers on an infinite 1D lattice is studied whereby the intrinsic bias of one particle is equal and opposite to that of the other. The propagator for this system is solved exactly and expressions for the mean displacement and mean square displacement (MSD) are found. Depending on the nature of the intrinsic bias, the system’s behaviour displays two regimes, characterised by (i) the particles moving towards each other and (ii) away from each other, both qualitatively different from the case of no bias. The continuous-space limit of the propagator is found and is shown to solve a Fokker-Planck equation for two biased, mutually exclusive Brownian particles with equal and opposite drift velocity. Connections to territorial dynamics in animal populations are discussed.
Mechanisms and Kinetics of Radical Reaction of O(1D,3P) + HCN System
Institute of Scientific and Technical Information of China (English)
HUANG Yu-Cheng; DU Jin-Yan; JU Xue-Hai; YE Shi-Yong; ZHOU Tao
2008-01-01
The reaction of HCN with O(1D, 3P) radical has been investigated by density functional theory (DFT) and ab initio methods. The stationary points on the reaction paths(reactants, intermediates and products) were optimized at the (U)B3LYP/aug-cc-pVTZ level.Single-point calculations were performed at the (U)QCISD(T)/aug-cc-pVTZ level for the optimized structures and all the total energies were corrected by zero-point energy. It is shown that there exist three competing mechanisms of oxygen attacking nitrogen O→N, oxygen attacking carbon O→C and oxygen attacking hydrogen O→H. The rate constants were obtained via Eyring transition-state theory in the temperature range of 600～2000 K. The linear relationship between lnk and 1/T was presented. The results show that path 1 is the main reaction channel and the product of NCO + H is predominant.