WorldWideScience

Sample records for single major band

  1. Changing optical band structure with single photons

    Science.gov (United States)

    Albrecht, Andreas; Caneva, Tommaso; Chang, Darrick E.

    2017-11-01

    Achieving strong interactions between individual photons enables a wide variety of exciting possibilities in quantum information science and many-body physics. Cold atoms interfaced with nanophotonic structures have emerged as a platform to realize novel forms of nonlinear interactions. In particular, when atoms are coupled to a photonic crystal waveguide, long-range atomic interactions can arise that are mediated by localized atom-photon bound states. We theoretically show that in such a system, the absorption of a single photon can change the band structure for a subsequent photon. This occurs because the first photon affects the atoms in the chain in an alternating fashion, thus leading to an effective period doubling of the system and a new optical band structure for the composite atom-nanophotonic system. We demonstrate how this mechanism can be engineered to realize a single-photon switch, where the first incoming photon switches the system from being highly transmissive to highly reflective, and analyze how signatures can be observed via non-classical correlations of the outgoing photon field.

  2. SINGLE-BAND, TRIPLE-BAND, OR MULTIPLE-BAND HUBBARD MODELS

    NARCIS (Netherlands)

    ESKES, H; SAWATZKY, GA

    1991-01-01

    The relevance of different models, such as the one-band t-J model and the three-band Emery model, as a realistic description of the electronic structure of high-T(c) materials is discussed. Starting from a multiband approach using cluster calculations and an impurity approach, the following

  3. A bespoke single-band Hubbard model material

    Science.gov (United States)

    Griffin, S. M.; Staar, P.; Schulthess, T. C.; Troyer, M.; Spaldin, N. A.

    2016-02-01

    The Hubbard model, which augments independent-electron band theory with a single parameter to describe electron-electron correlations, is widely regarded to be the "standard model" of condensed-matter physics. The model has been remarkably successful at addressing a range of correlation phenomena in solids, but it neglects many behaviors that occur in real materials, such as phonons, long-range interactions, and, in its simplest form, multiorbital effects. Here, we use ab initio electronic structure methods to design a material whose Hamiltonian matches as closely as possible that of the single-band Hubbard model. Our motivation is to compare the measured properties of our new material to those predicted by reliable theoretical solutions of the Hubbard model to determine the relevance of the model in the description of real materials. After identifying an appropriate crystal class and several appropriate chemistries, we use density-functional theory and dynamical mean-field theory to screen for the desired electronic band structure and metal-insulator transition. We then explore the most promising candidates for structural stability and suitability for doping, and we propose specific materials for subsequent synthesis. Finally, we identify a regime—that should manifest in our bespoke material—in which the single-band Hubbard model on a triangular lattice exhibits exotic d -wave superconductivity.

  4. Single-carrier impact ionization favored by a limited band dispersion

    OpenAIRE

    Darbandi, A.; Rubel, O.

    2012-01-01

    A critical requirement for high gain and low noise avalanche photodiodes is the single-carrier avalanche multiplication. We propose that the single-carrier avalanche multiplication can be achieved in materials with a limited width of the conduction or valence band resulting in a restriction of kinetic energy for one of the charge carriers. This feature is not common to the majority of technologically relevant semiconductors, but it is observed in chalcogenides, such as Selenium and compound I...

  5. A single sensor and single actuator approach to performance tailoring over a prescribed frequency band.

    Science.gov (United States)

    Wang, Jiqiang

    2016-03-01

    Restricted sensing and actuation control represents an important area of research that has been overlooked in most of the design methodologies. In many practical control engineering problems, it is necessitated to implement the design through a single sensor and single actuator for multivariate performance variables. In this paper, a novel approach is proposed for the solution to the single sensor and single actuator control problem where performance over any prescribed frequency band can also be tailored. The results are obtained for the broad band control design based on the formulation for discrete frequency control. It is shown that the single sensor and single actuator control problem over a frequency band can be cast into a Nevanlinna-Pick interpolation problem. An optimal controller can then be obtained via the convex optimization over LMIs. Even remarkable is that robustness issues can also be tackled in this framework. A numerical example is provided for the broad band attenuation of rotor blade vibration to illustrate the proposed design procedures. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

  6. Two hundred seventy-five single-incision laparoscopic gastric band insertions: what have we learnt?

    Science.gov (United States)

    Murgatroyd, Beth; Chakravartty, Saurav; Sarma, Diwakar R; Patel, Ameet G

    2014-07-01

    Single-incision surgery in the morbidly obese patient has not been widely adopted, but remains a popular choice amongst patients. In the bariatric patient, it presents its own surgical challenges with hepatomegaly and increased abdominal adiposity. Here, we present our experience of 275 single-incision laparoscopic gastric bands.Between June 2009 and April 2013, 275 obese patients underwent single-incision laparoscopic adjustable gastric banding through a single incision using a multichannel single port and via a pars flaccida approach. Prospective data collection was undertaken including operating time, additional ports and additional procedures undertaken.In this series, median operative time was 60 (range 34-170) min. An additional port was placed in 15 patients (5%), including two conversions to four-port technique (0.7%). Of these patients (n = 15), the majority were male (p rate of success for all BMIs. Following 275 single-incision band insertions additional port placements were more commonly required in male patients, BMI >45 and earlier in the learning curve.

  7. Single and multi-band electromagnetic induced transparency-like metamaterials with coupled split ring resonators

    Science.gov (United States)

    Bagci, Fulya; Akaoglu, Baris

    2017-08-01

    We present a metamaterial configuration exhibiting single and multi-band electromagnetic induced transparency (EIT)-like properties. The unit cell of the single band EIT-like metamaterial consists of a multi-split ring resonator surrounded by a split ring resonator. The multi-split ring resonator acts as a quasi-dark or dark resonator, depending on the polarization of the incident wave, and the split ring resonator serves as the bright resonator. Combination of these two resonators results in a single band EIT-like transmission inside the stop band. EIT-like transmission phenomenon is also clearly observed in the measured transmission spectrum at almost the same frequencies for vertical and horizontal polarized waves, and the numerical results are verified for normal incidence. Moreover, multi-band transmission windows are created within a wide band by combining the two slightly different single band EIT-like metamaterial unit cells that exhibit two different coupling strengths inside a supercell configuration. Group indices as high as 123 for single band and 488 for tri-band transmission, accompanying with high transmission rates (over 80%), are achieved, rendering the metamaterial very suitable for multi-band slow light applications. It is shown that the group delay of the propagating wave can be increased and dynamically controlled by changing the polarization angle. Multi-band EIT-like transmission is also verified experimentally, and a good agreement with simulations is obtained. The proposed novel methodology for obtaining multi-band EIT, which takes advantage of a supercell configuration by hosting slightly different configured unit cells, can be utilized for easily formation and manipulation of multi-band transmission windows inside a stop band.

  8. Mini-stop bands in single heterojunction photonic crystal waveguides

    KAUST Repository

    Shahid, N.

    2013-01-01

    Spectral characteristics of mini-stop bands (MSB) in line-defect photonic crystal (PhC) waveguides and in heterostructure PhC waveguides having one abrupt interface are investigated. Tunability of the MSB position by air-fill factor heterostructure PhC waveguides is utilized to demonstrate different filter functions, at optical communication wavelengths, ranging from resonance-like to wide band pass filters with high transmission. The narrowest filter realized has a resonance-like transmission peak with a full width at half maximum of 3.4 nm. These devices could be attractive for coarse wavelength selection (pass and drop) and for sensing applications. 2013 Copyright 2013 Author(s). This article is distributed under a Creative Commons Attribution 3.0 Unported License.

  9. Single and dual band 77/95/110 GHz metamaterial absorbers on flexible polyimide substrate

    Science.gov (United States)

    Singh, Pramod K.; Korolev, Konstantin A.; Afsar, Mohammed N.; Sonkusale, Sameer

    2011-12-01

    Ultra thin millimeter-wave absorbers on flexible polyimide substrate utilizing metamaterials are implemented for single and dual frequency bands in an emerging frequency spectrum of 77, 95, and 110 GHz. The dual band absorber is designed using a novel approach of imbedding high frequency resonator inside low frequency resonator capable of absorbing electromagnetic energy at both 77 and 110 GHz bands simultaneously. The total thickness of the absorber is just 126 μm (almost 1/20th of the wavelength). Measured peak absorptions for single frequency absorbers are 92, 94, and 99% at 77.2, 94.8, and 109.5 GHz, respectively, and for dual band absorber 92% at 77 GHz and 94% at 109.8 GHz.

  10. Cellophane banding for the gradual attenuation of single extrahepatic portosystemic shunts in eleven dogs.

    Science.gov (United States)

    Youmans, K R; Hunt, G B

    1998-08-01

    To evaluate the efficacy and short term effects of a cellophane banding technique for progressive attenuation of canine single extrahepatic portosystemic shunts. A prospective trial of 11 dogs with single congenital extrahepatic shunts. Rectal ammonia tolerance testing and routine biochemical tests were performed preoperatively on all dogs. In seven dogs, preoperative abdominal Doppler ultrasonography was also performed. Exploratory laparotomy revealed a single extrahepatic portocaval shunt in each animal, which was attenuated using a cellophane band with an internal diameter of 2 to 3 mm. The abdomen was closed routinely. Follow-up biochemical analysis and abdominal Doppler ultrasonography or splenoportography were performed postoperatively. The shunt was not amenable to total ligation in 11 dogs, based upon reported criteria. All dogs recovered uneventfully from surgery without evidence of portal hypertension, and showed clinical improvement thereafter. Shunt occlusion was deemed to have occurred in 10 dogs based on resolution of biochemical and/or sonographic abnormalities. One dog continued to have sonographic evidence of portosystemic shunting when evaluated 3 weeks after surgery, despite normal ammonia tolerance, but was lost to subsequent follow-up. Two dogs, in which 3 mm cellophane bands were placed, experienced delayed shunt occlusion. Cellophane banding is simple to perform, and causes progressive attenuation of single extrahepatic shunts in dogs. Further work is needed to determine the maximum diameter of a cellophane band which will produce total attenuation, and the long-term safety and reliability of the treatment.

  11. HARMONI : A single-field wide-band integral-field spectrograph for the European ELT

    NARCIS (Netherlands)

    Thatte, Niranjan; Tecza, Mathias; Clarke, Fraser; Davies, Roger L.; Remillieux, Alban; Bacon, Roland; Lunney, David; Arribas, Santiago; Mediavilla, Evencio; Gago, Fernando; Bezawada, Naidu; Ferruit, Pierre; Fragoso, Ana; Freeman, David; Fuentes, Javier; Fusco, Thierry; Gallie, Angus; Garcia, Adolfo; Goodsall, Timothy; Gracia, Felix; Jarno, Aurelien; Kosmalski, Johan; Lynn, James; McLay, Stuart; Montgomery, David; Pecontal, Arlette; Schnetler, Hermine; Smith, Harry; Sosa, Dario; Battaglia, Giuseppina; Bowles, Neil; Colina, Luis; Emsellem, Eric; Garcia-Perez, Ana; Gladysz, Szymon; Hook, Isobel; Irwin, Patrick; Jarvis, Matt; Kennicutt, Robert; Levan, Andrew; Longmore, Andy; Magorrian, John; McCaughrean, Mark; Origlia, Livia; Rebolo, Rafael; Rigopoulou, Dimitra; Ryan, Sean; Swinbank, Mark; Tanvir, Nial; Tolstoy, Eline; Verma, Aprajita

    We describe the results of a Phase A study for a single field, wide band, near-infrared integral field spectrograph for the European Extremely Large Telescope (E-ELT). HARMONI, the High Angular Resolution Monolithic Optical & Nearinfrared Integral field spectrograph, provides the E-ELT's core

  12. Synchro-Betatron Stop-Bands Due to a Single Crab Cavity

    Energy Technology Data Exchange (ETDEWEB)

    Chao, A

    2004-06-17

    We analyze the stop-band due to crab cavities for horizontal tunes that are either close to integers or close to half integers. The latter case is relevant for today's electron/positron colliders. We compare this stop-band to that created by dispersion in an accelerating cavity and show that a single typical crab cavity creates larger stop-bands than a typical dispersion at an accelerating cavity. We furthermore analyze whether it is beneficial to place the crab cavity at a position where the dispersion and its slope vanish. We find that this choice is worth while if the horizontal tune is close to a half integer, but not if it is close to an integer. Furthermore we find that stop-bands can be avoided when the horizontal tune is located at a favorable side of the integer or the half integer. While we are here concerned with the installation of a single crab cavity in a storage ring, we show that the stop-bands can be weakened, although not eliminated, significantly when two crab cavities per ring are chosen suitably.

  13. High spectral efficient W-band optical/wireless system employing single-sideband single-carrier modulation.

    Science.gov (United States)

    Ho, Chun-Hung; Lin, Chun-Ting; Cheng, Yu-Hsuan; Huang, Hou-Tzu; Wei, Chia-Chien; Chi, Sien

    2014-02-24

    With broader available bandwidth, W-band wireless transmission has attracted a lot of interests for future Giga-bit communication. In this article, we experimentally demonstrate W-band radio-over-fiber (RoF) system employing single-sideband single-carrier (SSB-SC) modulation with lower peak-to-average-power ratio (PAPR) than orthogonal frequency division multiplex (OFDM). To overcome the inter-symbol interference (ISI) of the penalty from uneven frequency response and SSB-SC modulation, frequency domain equalizer (FDE) and decision feedback equalizer (DFE) are implemented. We discuss the maximum available bandwidth of different modulation formats between SSB-SC and OFDM signals at the BER below forward error correction (FEC) threshold (3.8 × 10(-3)). Up to 50-Gbps 32-QAM SSB-SC signals with spectral efficiency of 5 bit/s/Hz can be achieved.

  14. Determination of band offsets at GaN/single-layer MoS2 heterojunction

    KAUST Repository

    Tangi, Malleswararao

    2016-07-25

    We report the band alignment parameters of the GaN/single-layer (SL) MoS2 heterostructure where the GaN thin layer is grown by molecular beam epitaxy on CVD deposited SL-MoS2/c-sapphire. We confirm that the MoS2 is an SL by measuring the separation and position of room temperature micro-Raman E1 2g and A1 g modes, absorbance, and micro-photoluminescence bandgap studies. This is in good agreement with HRTEM cross-sectional analysis. The determination of band offset parameters at the GaN/SL-MoS2 heterojunction is carried out by high-resolution X-ray photoelectron spectroscopy accompanying with electronic bandgap values of SL-MoS2 and GaN. The valence band and conduction band offset values are, respectively, measured to be 1.86 ± 0.08 and 0.56 ± 0.1 eV with type II band alignment. The determination of these unprecedented band offset parameters opens up a way to integrate 3D group III nitride materials with 2D transition metal dichalcogenide layers for designing and modeling of their heterojunction based electronic and photonic devices.

  15. Band Alignment at GaN/Single-Layer WSe2 Interface

    KAUST Repository

    Tangi, Malleswararao

    2017-02-21

    We study the band discontinuity at the GaN/single-layer (SL) WSe2 heterointerface. The GaN thin layer is epitaxially grown by molecular beam epitaxy on chemically vapor deposited SL-WSe2/c-sapphire. We confirm that the WSe2 was formed as an SL from structural and optical analyses using atomic force microscopy, scanning transmission electron microscopy, micro-Raman, absorbance, and microphotoluminescence spectra. The determination of band offset parameters at the GaN/SL-WSe2 heterojunction is obtained by high-resolution X-ray photoelectron spectroscopy, electron affinities, and the electronic bandgap values of SL-WSe2 and GaN. The valence band and conduction band offset values are determined to be 2.25 ± 0.15 and 0.80 ± 0.15 eV, respectively, with type II band alignment. The band alignment parameters determined here provide a route toward the integration of group III nitride semiconducting materials with transition metal dichalcogenides (TMDs) for designing and modeling of their heterojunction-based electronic and optoelectronic devices.

  16. Narrow band wavelength selective filter using grating assisted single ring resonator

    Energy Technology Data Exchange (ETDEWEB)

    Prabhathan, P., E-mail: PPrabhathan@ntu.edu.sg; Murukeshan, V. M. [Centre for Optical and Laser Engineering (COLE), School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore)

    2014-09-15

    This paper illustrates a filter configuration which uses a single ring resonator of larger radius connected to a grating resonator at its drop port to achieve single wavelength selectivity and switching property with spectral features suitable for on-chip wavelength selection applications. The proposed configuration is expected to find applications in silicon photonics devices such as, on-chip external cavity lasers and multi analytic label-free biosensors. The grating resonator has been designed for a high Q-factor, high transmittivity, and minimum loss so that the wavelength selectivity of the device is improved. The proof-of-concept device has been demonstrated on a Silicon-on-Insulator (SOI) platform through electron beam lithography and Reactive Ion Etching (RIE) process. The transmission spectrum shows narrow band single wavelength selection and switching property with a high Free Spectral Range (FSR) ∼60 nm and side band rejection ratio >15 dB.

  17. Laparoendoscopic single-site gastric bands versus standard multiport gastric bands: a comparison of technical learning curve measured by surgical time.

    Science.gov (United States)

    Gawart, Matthew; Dupitron, Sabine; Lutfi, Rami

    2012-03-01

    We aimed to evaluate our learning curve comparing surgical time of laparoendoscopic single-site (LESS) banding with multiport laparoscopy. We performed a retrospective analysis of prospectively collected data comparing our first 48 LESS bands with our first 50 multiport laparoscopic bands at our institution. We then compared the first 24 LESS bands with the last 24 bands. The average body mass index for the LESS group was significantly lower than for the laparoscopic group (43.19 vs 48.3; P < .0001). The surgical time was much faster toward the second half of our experience performing the LESS procedure (85.34 vs 68.8; P = .0055). LESS banding took significantly longer than our early traditional laparoscopic adjustable gastric banding (76.85 vs 64.4; P = .0015). We conclude that in experienced hands, single-incision banding is feasible and safe to perform. Long-term data are needed to prove that LESS banding is as good a surgery as traditional laparoscopic surgery. Copyright © 2012 Elsevier Inc. All rights reserved.

  18. Single-band negative differential resistance in metallic armchair MoS2 nanoribbons

    International Nuclear Information System (INIS)

    Chen, Cheng; Wang, Xue-Feng; Li, Yao-Sheng; Cheng, Xue-Mei; Yao, A-Long

    2017-01-01

    Semiconductor armchair MoS 2 nanoribbons can be converted into conductors by edge functionalization of H atoms or OH groups. Those metallic nanoribbons exhibit I – V characteristics of a single half-filled band with strong negative differential resistance (NDR) under a voltage bias less than 1 V. This originates from the spatial separation between electrons in the conduction and valence bands. The NDR becomes spin dependent if the H atoms or OH groups are not uniformly adsorbed on the edge. Furthermore, the spin polarization can be greatly enhanced in heterojunctions of H- and OH-passivated nanoribbons. (paper)

  19. Single Pixel, Single Band Microstrip Antenna for Sub-Millimeter Wavelength Detection Using Transition Edge Superconducting Bolometric Receivers

    Science.gov (United States)

    Hunt, Cynthia; Bock, Jamie J.; Day, Peter K.; Goldin, Alexey; Lange, Andrew E.; Leduc, Henry G.; Vayonakis, Anastasios; Zmuidzinas, Jonas

    We are developing a single pixel antenna coupled bolometric detector as a precursor to the SAMBA (Superconducting Antenna-coupled Multi-frequency Bolometric Array) instrument. Our device consists of a dual slot microstrip antenna coupled to an Al/Ti/Au voltage-biased transition edge superconducting bolometer (TES). The coupling architecture involves propagating the signal along superconducting microstrip lines and terminating the lines at a normal metal resistor on a thermally isolated island. The device, which is inherently polarization sensitive, is optimized to for 100GHz band measurements, ideal for future implementation as an astronomical sub-millimeter instrument. We will present recent tests of these single pixel detectors.

  20. Intercomparison of attenuation correction algorithms for single-polarized X-band radars

    Science.gov (United States)

    Lengfeld, K.; Berenguer, M.; Sempere Torres, D.

    2018-03-01

    Attenuation due to liquid water is one of the largest uncertainties in radar observations. The effects of attenuation are generally inversely proportional to the wavelength, i.e. observations from X-band radars are more affected by attenuation than those from C- or S-band systems. On the other hand, X-band radars can measure precipitation fields in higher temporal and spatial resolution and are more mobile and easier to install due to smaller antennas. A first algorithm for attenuation correction in single-polarized systems was proposed by Hitschfeld and Bordan (1954) (HB), but it gets unstable in case of small errors (e.g. in the radar calibration) and strong attenuation. Therefore, methods have been developed that restrict attenuation correction to keep the algorithm stable, using e.g. surface echoes (for space-borne radars) and mountain returns (for ground radars) as a final value (FV), or adjustment of the radar constant (C) or the coefficient α. In the absence of mountain returns, measurements from C- or S-band radars can be used to constrain the correction. All these methods are based on the statistical relation between reflectivity and specific attenuation. Another way to correct for attenuation in X-band radar observations is to use additional information from less attenuated radar systems, e.g. the ratio between X-band and C- or S-band radar measurements. Lengfeld et al. (2016) proposed such a method based isotonic regression of the ratio between X- and C-band radar observations along the radar beam. This study presents a comparison of the original HB algorithm and three algorithms based on the statistical relation between reflectivity and specific attenuation as well as two methods implementing additional information of C-band radar measurements. Their performance in two precipitation events (one mainly convective and the other one stratiform) shows that a restriction of the HB is necessary to avoid instabilities. A comparison with vertically pointing

  1. A natural-color mapping for single-band night-time image based on FPGA

    Science.gov (United States)

    Wang, Yilun; Qian, Yunsheng

    2018-01-01

    A natural-color mapping for single-band night-time image method based on FPGA can transmit the color of the reference image to single-band night-time image, which is consistent with human visual habits and can help observers identify the target. This paper introduces the processing of the natural-color mapping algorithm based on FPGA. Firstly, the image can be transformed based on histogram equalization, and the intensity features and standard deviation features of reference image are stored in SRAM. Then, the real-time digital images' intensity features and standard deviation features are calculated by FPGA. At last, FPGA completes the color mapping through matching pixels between images using the features in luminance channel.

  2. The use of simultaneous confidence bands for comparison of single parameter fluorescent intensity data.

    Science.gov (United States)

    Kim, Dongha; Donnenberg, Vera S; Wilson, John W; Donnenberg, Albert D

    2016-01-01

    Despite the utility of multiparameter flow cytometry for a wide variety of biological applications, comparing single parameter histograms of fluorescence intensity remains a mainstay of flow cytometric analysis. Even comparisons requiring multiparameter gating strategies often end with single parameter histograms as the final readout. When histograms overlap, analysis relies on comparison of mean or median fluorescence intensities, or determination of percent positive based on an arbitrary cutoff. Earlier attempts to address this problem utilized either simple channel-by-channel subtraction without statistical evaluation, or the Kolmogorov-Smirnov (KS) or Chi-square test statistics, both of which proved to be overly sensitive to small and biologically insignificant differences. Here we present a method for the comparison of two single-parameter histograms based on difference curves and their simultaneous confidence bands generated by bootstrapping raw channel data. Bootstrapping is a nonparametric statistical approach that can be used to generate confidence intervals without distributional assumptions about the data. We have constructed simultaneous confidence bands and show them to be superior to KS and Cox methods. The method constructs 95% confidence bands about the difference curves, provides a P value for the comparison and calculates the area under the difference curve (AUC) as an estimate of percent positive and the area under the confidence band (AUCSCB95), providing a lower estimate of the percent positive. To demonstrate the utility of this new approach we have examined single-color fluorescence intensity data taken from a cell surface proteomic survey of a lung cancer cell line (A549) and a published fluorescence intensity data from a rhodamine efflux assay of P-glycoprotein activity, comparing rhodamine 123 loading and efflux in CD4 and CD8 T-cell populations. SAS source code is provided as supplementary material. © 2015 International Society for

  3. LOCAL BENCHMARKS FOR THE EVOLUTION OF MAJOR-MERGER GALAXIES-SPITZER OBSERVATIONS OF A K-BAND SELECTED SAMPLE

    International Nuclear Information System (INIS)

    Xu, C. Kevin; Cheng Yiwen; Lu Nanyao; Mazzarella, Joseph M.; Cutri, Roc; Domingue, Donovan; Huang Jiasheng; Gao Yu; Sun, W.-H.; Surace, Jason

    2010-01-01

    We present Spitzer observations for a sample of close major-merger galaxy pairs (KPAIR sample) selected from cross-matches between the Two Micron All Sky Survey and Sloan Digital Sky Survey Data Release 3. The goals are to study the star formation activity in these galaxies and to set a local bench mark for the cosmic evolution of close major mergers. The Spitzer KPAIR sample (27 pairs, 54 galaxies) includes all spectroscopically confirmed spiral-spiral (S+S) and spiral-elliptical (S+E) pairs in a parent sample that is complete for primaries brighter than K = 12.5 mag, projected separations of 5 h -1 kpc ≤ s ≤ 20 h -1 kpc, and mass ratios ≤2.5. The Spitzer data, consisting of images in seven bands (3.6, 4.5, 5.8, 8, 24, 70, 160 μm), show very diversified IR emission properties. Compared to single spiral galaxies in a control sample, only spiral galaxies in S+S pairs show significantly enhanced specific star formation rate (sSFR = SFR/M), whereas spiral galaxies in S+E pairs do not. Furthermore, the SFR enhancement of spiral galaxies in S+S pairs is highly mass-dependent. Only those with M ∼> 10 10.5 M sun show significant enhancement. Relatively low-mass (M ∼ 10 10 M sun ) spirals in S+S pairs have about the same SFR/M compared to their counterparts in the control sample, while those with 10 11 M sun have on average a ∼3 times higher SFR/M than single spirals. There is evidence for a correlation between the global star formation activities (but not the nuclear activities) of the component galaxies in massive S+S major-merger pairs (the H olmberg effect ) . There is no significant difference in the SFR/M between the primaries and the secondaries, nor between spirals of SEP KPAIR =2.54 x 10 -4 (M sun yr -1 Mpc -3 ).

  4. Characterestics of pico-second single bunch at the S-band linear accelerator

    International Nuclear Information System (INIS)

    Uesaka, Mitsuru; Kozawa, Takahiro; Kobayashi, Toshiaki; Ueda, Toru; Miya, Kenzo

    1994-01-01

    Measurement of the bunch structure of a pico-second single bunch was performed using a femto-second streak camera at the S-band linear accelerator of the University of Tokyo. The aim of this research is to investigate the feasibility of the generation of a femto-second single bunch at the S-band linac. The details of the bunch structure and energy spectrum of an original single bunch were precisely investigated in several operation modes where the RF phases in accelerating tubes and a prebuncher were varied. The femto-second streak camera was utilized to measure the bunch structure by one shot via Cherenkov radiation emitted by the electrons in the bunch. Next, an experiment for magnetic pulse compression of the original single bunch was carried out. Pulse shapes of the compressed bunchs for different energy modulation were also obtained by measuring Cherenkov radiation by one shot using the femto-second streak camera. Prior to the experiment, numerical tracking analysis to determine operating parameters for the magnetic pulse compression was also done. Measured pulse widths were compared with calculated ones. Finally, a 2 ps (full width at half maximum; FWHM) single bunch with an electric charge of 0.3 nC could be generated by the magnetic pulse compression. ((orig.))

  5. Two-band induced superconductivity in single-layer graphene and topological insulator bismuth selenide

    Science.gov (United States)

    Talantsev, E. F.; Crump, W. P.; Tallon, J. L.

    2018-01-01

    Proximity-induced superconductivity in single-layer graphene (SLG) and in topological insulators represent almost ideal examples of superconductivity in two dimensions. Fundamental mechanisms governing superconductivity in the 2D limit are of central interest for modern condensed-matter physics. To deduce fundamental parameters of superconductor/graphene/superconductor and superconductor/bismuth selenide/superconductor junctions we investigate the self-field critical currents in these devices using the formalism of the Ambegaokar–Baratoff model. Our central finding is that the induced superconducting state in SLG and bismuth selenide each exhibits gapping on two superconducting bands. Based on recent results obtained on ultra-thin films of natural superconductors, including single-atomic layer of iron selenide, double and triple atomic layers of gallium, and several atomic layer tantalum disulphide, we conclude that a two-band induced superconducting state in SLG and bismuth selenide is part of a wider, more general multiple-band phenomenology of currently unknown origin.

  6. Energy Band Gap Study of Semiconducting Single Walled Carbon Nanotube Bundle

    Science.gov (United States)

    Elkadi, Asmaa; Decrossas, Emmanuel; El-Ghazaly, Samir

    2013-01-01

    The electronic properties of multiple semiconducting single walled carbon nanotubes (s-SWCNTs) considering various distribution inside a bundle are studied. The model derived from the proposed analytical potential function of electron density for na individual s-SWCNT is general and can be easily applied to multiple nanotubes. This work demonstrates that regardless the number of carbon nanotubes, the strong coupling occurring between the closet neighbors reduces the energy band gap of the bundle by 10%. As expected, the coupling is strongly dependent on the distance separating the s-SWCNTs. In addition, based on the developed model, it is proposed to enhance this coupling effect by applying an electric field across the bundle to significantly reduce the energy band gap of the bundle by 20%.

  7. Validity of single term energy expression for ground state rotational band of even-even nuclei

    International Nuclear Information System (INIS)

    Sharma, S.; Kumar, R.; Gupta, J.B.

    2005-01-01

    Full text: There are large numbers of empirical studies of gs band of even-even nuclei in various mass regions. The Bohr-Mottelson's energy expression is E(I) = AX + BX 2 +CX 3 +... where X = I(I+1). The anharmonic vibrator energy expression is: E(I) = al + bl 2 + cl 3 SF model with energy expression: E(I)= pX + qI + rXI... where the terms represents the rotational, vibrational and R-V interaction energy, respectively. The validity f the various energy expressions with two terms had been tested by Sharma for light, medium and heavy mass regions using R I s. R 4 plots (where, spin I=6, 8, 10, 12), which are parameter independent. It was also noted, that of the goodness of energy expression can be judged with the minimum input of energies (i.e. only 2 parameters) and predictability's of the model p to high spins. Recently, Gupta et. al proposed a single term energy expression (SSTE) which was applied for rare earth region. This proposed power law reflected the unity of rotation - vibration in a different way and was successful in explaining the structure of gs-band. It will be useful for test the single term energy expression for light and heavy mass region. The single term expression for energy of ground state band can be written as: E I =axI b , where the index b and the coefficient a are the constant for the band. The values of b+1 and a 1 are as follows: b 1 =log(R 1 )/log(I/2) and a 1 =E I /I b ... The following results were gained: 1) The sharp variation in the value of index b at given spin will be an indication of the change in the shape of the nucleus; 2) The value of E I /I b is fairly constant with spin below back-bending, which reflects the stability of shape with spin; 3) This proposed power law is successful in explaining the structure of gs-band of nuclei

  8. Single-stage gain-clamped L-band EDFA with C-band ASE self-oscillation in ring cavity

    International Nuclear Information System (INIS)

    Mahdi, M A; Al-Mansoori, M H; Bakar, A A A; Shaari, S; Zamzuri, A K

    2008-01-01

    We demonstrate single-stage gain-clamped L-band Er 3+ -doped fiber amplifier (EDFA) utilizing self-oscillation modes as the control light. The amplifier structure exploits the characteristics of C/L-band coupler to isolate between lasing modes and L-band signal. The self-lasing cavity modes are obtained without any tunable bandpass filter in the loop and generated from the amplified spontaneous emission in the C-band region. The amplifier configuration has lower noise figures as opposed to a dual-stage partially gain-clamped amplifier. The gain and noise figure fluctuations are less than ± 0.4 dB in the gain-clamping region. The transient analysis confirms that the maximum power excursion is less than 0.3 dB for 10-dB add/drop

  9. Ruptured Jejunal Diverticulum Due to a Single-Band Small Bowel Obstruction

    Directory of Open Access Journals (Sweden)

    Rajaraman Durai

    2008-01-01

    Full Text Available Jejunal diverticulosis is rare and often goes unnoticed until complications occur. The diverticula are true, acquired diverticula and often asymptomatic. Jejunal diverticulosis can be associated with diverticulosis of the duodenum, ileum, and colon. Here we describe a patient with known severe diverticular disease of the large bowel, who presented acutely with abdominal pain and signs of generalised peritonitis. Laparotomy showed ruptured jejunal diverticulosis with a single band over the terminal ileum, causing small bowel obstruction. Spontaneous perforation of a jejunal diverticulum is rare and is usually an intraoperative finding. One should exclude a precipitating cause, such as coexisting distal obstruction, stricture, or a foreign body.

  10. Ruptured Jejunal Diverticulum Due to a Single-Band Small Bowel Obstruction

    Science.gov (United States)

    Durai, Rajaraman; Sinha, Ashish; Khan, Mihir; Hoque, Happy; Kerwat, Rajab

    2008-01-01

    Jejunal diverticulosis is rare and often goes unnoticed until complications occur. The diverticula are true, acquired diverticula and often asymptomatic. Jejunal diverticulosis can be associated with diverticulosis of the duodenum, ileum, and colon. Here we describe a patient with known severe diverticular disease of the large bowel, who presented acutely with abdominal pain and signs of generalised peritonitis. Laparotomy showed ruptured jejunal diverticulosis with a single band over the terminal ileum, causing small bowel obstruction. Spontaneous perforation of a jejunal diverticulum is rare and is usually an intraoperative finding. One should exclude a precipitating cause, such as coexisting distal obstruction, stricture, or a foreign body. PMID:18836661

  11. A single term expression of ground band level energies of a soft rotor

    International Nuclear Information System (INIS)

    Gupta, J.B.; Kavathekar, A.K.; Sharma, R.

    1995-01-01

    A single term expression in the form of a Power law with two unknown coefficients is proposed. It explains fairly well the energies of ground bands in even-even nuclei in the A = 150-200 region. The index ''b'' and the coefficient ''a'' in this expression are fairly constant independent of the level spin, below the back bending energy. Variation of average ''a'' and ''b'' with Z and N, and with the valence nucleon pair product N p N n is also illustrated and agrees with general expectations. (orig.)

  12. Fine Structure of the Low-Frequency Raman Phonon Bands of Single-Wall Carbon Nanotubes

    Science.gov (United States)

    Iliev, M. N.; Litvinchuk, A. P.; Arepalli, S.; Nikolaev, P.; Scott, C. D.

    1999-01-01

    The Raman spectra of singled-wall carbon nanotubes (SWNT) produced by laser and are process were studied between 5 and 500 kappa. The line width vs. temperature dependence of the low-frequency Raman bands between 150 and 200/ cm deviates from that expected for phonon decay through phonon-phonon scattering mechanism. The experimental results and their analysis provided convincing evidence that each of the low-frequency Raman lines is a superposition of several narrower Raman lines corresponding to tubes of nearly the same diameter. The application of Raman spectroscopy to probe the distribution of SWNT by both diameter and chirality is discussed.

  13. Efficient frequency downconversion at the single photon level from the red spectral range to the telecommunications C-band.

    Science.gov (United States)

    Zaske, Sebastian; Lenhard, Andreas; Becher, Christoph

    2011-06-20

    We report on single photon frequency downconversion from the red part of the spectrum (738 nm) to the telecommunications C-band. By mixing attenuated laser pulses with an average photon number per pulse telecommunications wavelengths.

  14. Energy-expending behaviour in frightened caribou when dispersed singly or in small bands

    Directory of Open Access Journals (Sweden)

    Otto Blehr

    1997-04-01

    Full Text Available The behaviour of single, and small bands of caribou (Rangifer tarandus groenlandicus when confronted by humans was compared with the energy—saving behaviour zoologists have ascribed to caribou in encounters with non-hunting wolves (Canis lupus. When confronted by me, or upon getting my scent, caribou ran away on all occasions. Their flight was occasionally interrupted by short stops to look back in my direction, but would continue on all occasions until they were out of sight. This behaviour is inconsistent with the one ascribed to caribou by zoologists when the intruder is a wolf instead of a human. In their view, the caribou stop their flight soon after the wolf gives up the chase, and accordingly save energy owing to their ability to distinguish between hunting and non-hunting wolves. However, small bands of caribou, as well as single animals, have never been observed to behave in this manner. On the contrary, the behaviour of caribou in such encounters is known to follow the same pattern as in their encounters with humans. Energy—saving behaviour is, however, sometimes observed when caribou become inquisitive about something in their surroundings. They will then readily approach as well as try to get down-wind of the object. When the object does not induce fear, it may simply be ignored, or charged before the caribou calm down. The effect of this "confirming behaviour" is that energy which would otherwise have been spent in needless flights from non-predators is saved.

  15. Modeling of the I V characteristics of single and double barrier tunneling diodes using A k · p band model

    Science.gov (United States)

    Mui, D.; Patil, M.; Chen, J.; Agarwala, S.; Kumar, N. S.; Morkoc, H.

    1989-11-01

    We model the I-V characteristics of single and double barrier tunneling diodes using the complex band structure of the tunneling barrier obtained from a k · p band model. Band-bending is calculated by solving two coupled 1-D Poisson's equations with a classical potential in the accumulation region. The transfer matrix method is used for the calculation of the transmission probability of the tunneling electron whose complex k-vector is obtained from the band structure. An energy dependent density of states effective mass which is also calculated from the band structure is used. I-V characteristics for In 0.53Ga 0.47As/In 0.52Al 0.48As/In 0.53Ga 0.47As single and double barrier tunneling diodes obtained from this model agree quantitatively with experiment.

  16. Adaptive Hysteresis Band Current Control for Transformerless Single-Phase PV Inverters

    DEFF Research Database (Denmark)

    Vázquez, Gerardo; Rodriguez, Pedro; Ordoñez, Rafael

    2009-01-01

    Current control based on hysteresis algorithms are widely used in different applications, such as motion control, active filtering or active/reactive power delivery control in distributed generation systems. The hysteresis current control provides to the system a fast and robust dynamic response,...... different single-phase PV inverter topologies, by means of simulations performed with PSIM. In addition, the behavior of the thermal losses when using each control structure in such converters has been studied as well.......Current control based on hysteresis algorithms are widely used in different applications, such as motion control, active filtering or active/reactive power delivery control in distributed generation systems. The hysteresis current control provides to the system a fast and robust dynamic response......, and requires a simple implementation in standard digital signal platforms. On the other hand, the main drawback of classical hysteresis current control lies in the fact that the switching frequency is variable, as the hysteresis band is fixed. In this paper a variable band hysteresis control algorithm...

  17. Orientation dependence of dispersion and band gap of PIMNT single crystals

    Science.gov (United States)

    He, Chongjun; Chen, Hongbing; Wang, Jiming; Gu, Xiaorong; Wu, Tong; Liu, Youwen

    2018-01-01

    As piezoelectric materials, optical properties of xPb(In1/2Nb1/2)O3-(1-x-y)Pb(Mg1/3Nb2/3)O3-yPbTiO3 single crystals were not perfectly known. Here refractive indices and optical transmission of 0.25Pb(In1/2Nb1/2)O3-0.42Pb(Mg1/3Nb2/3)O3- 0.33PbTiO3 (PIMNT) single crystal are investigated after poled along different directions. Cauchy dispersion equations of the refractive indices were obtained by least square fitting, which can be used to calculate the refractive indices in the low absorption wavelength range. After poled along [011] direction, the optical transmission of PIMNT single crystal is more than 65% above 0.5 μm, which is much higher than that of [001] and [111] directions. Energy band gap was obtained from absorption coefficient.

  18. Optical Properties and Band Gap of Single- and Few-Layer MoTe2 Crystals

    Science.gov (United States)

    Aslan, Ozgur Burak; Ruppert, Claudia; Heinz, Tony

    2015-03-01

    Single- and few-layer crystals of exfoliated MoTe2 have been characterized spectroscopically by photoluminescence, Raman scattering, and optical absorption measurements. We find that MoTe2 in the monolayer limit displays strong photoluminescence. On the basis of complementary optical absorption results, we conclude that monolayer MoTe2 is a direct-gap semiconductor with an optical band gap of 1.10 eV. This new monolayer material extends the spectral range of atomically thin direct-gap materials from the visible to the near-infrared. Supported by the NSF through Grant DMR-1124894 for sample preparation and characterization by the O?ce of Naval Research for analysis. C.R. acknowledges support from the Alexander von Humboldt Foundation.

  19. In-house L-band niobium single cell cavities at KEK

    International Nuclear Information System (INIS)

    Inoue, Hitoshi; Kobayashi, Yoshiharu; Funahashi, Yoshisato; Koizumi, Susumu; Saito, Kenji; Noguchi, Shuichi; Kako, Eiji; Shishido, Toshio

    1993-01-01

    For the TESLA (TeV Energy Superconducting Linear Accelerator) as an energy frontier accelerator of the next generation improving the performance of the niobium superconducting cavities is the most important issue and much reduction of fabrication cost of cavities is another key. Since manufacturing of niobium material requires hard techniques due to the easily oxidizable metal, fabrication of niobium cavities has been conducted in only companies providing enough equipments in Japan. KEK has accumulated the fabrication technics such as forming method by deep drawing, trimming, centering of beam tubes, electron beam welding and measurement of manufacturing error so on. We made in-house L-band single cell cavities using these technologies. In this paper we present these manufacturing of the niobium cavities and estimate the fabrication cost as exactly as possible. The manufacturing error is also described. (author)

  20. Tunable ultra-wide band-stop filter based on single-stub plasmonic-waveguide system

    Science.gov (United States)

    Chen, Zhiquan; Li, Hongjian; Li, Boxun; He, Zhihui; Xu, Hui; Zheng, Mingfei; Zhao, Mingzhuo

    2016-10-01

    A nanoscale plasmonic filter based on a single-stub coupled metal-dielectric-metal waveguide system is investigated theoretically and numerically. A tunable wide band-stop can be achieved by loading a metal bar into the stub. The band-stop originates from the direct coupling between the resonance modes. The bandwidth and the center wavelength of the band-stop can be tuned by changing the parameters of the metal bar. Compared with previously reported filters, the plasmonic system has the advantages of easy fabrication and compactness. Our results indicate that the proposed system has potential to be utilized in integrated optical circuits and tunable filters.

  1. Point defects in lines in single crystalline phosphorene: directional migration and tunable band gaps.

    Science.gov (United States)

    Li, Xiuling; Ma, Liang; Wang, Dayong; Zeng, Xiao Cheng; Wu, Xiaojun; Yang, Jinlong

    2016-10-20

    Extended line defects in two-dimensional (2D) materials can play an important role in modulating their electronic properties. During the experimental synthesis of 2D materials, line defects are commonly generated at grain boundaries between domains of different orientations. In this work, twelve types of line-defect structures in single crystalline phosphorene are examined by using first-principles calculations. These line defects are typically formed via migration and aggregation of intrinsic point defects, including the Stone-Wales (SW), single or double vacancy (SV or DV) defects. Our calculated results demonstrate that the migration of point defects in phosphorene is anisotropic, for instance, the lowest migration energy barriers are 1.39 (or 0.40) and 2.58 (or 0.49) eV for SW (or SV) defects in zigzag and armchair directions, respectively. The aggregation of point defects into lines is energetically favorable compared with the separated point defects in phosphorene. In particular, the axis of line defects in phosphorene is direction-selective, depending on the composed point defects. The presence of line defects effectively modulates the electronic properties of phosphorene, rendering the defect-containing phosphorene either metallic or semiconducting with a tunable band gap. Of particular interest is the fact that the SV-based line defect can behave as a metallic wire, suggesting a possibility to fabricate a circuit with subnanometer widths in the semiconducting phosphorene for nanoscale electronic application.

  2. Mining single-electron spectra of the interface states from a supercell band structure of silicene on an Ag (111 ) substrate with band-unfolding methodology

    Science.gov (United States)

    Iwata, Jun-Ichi; Matsushita, Yu-ichiro; Nishi, Hirofumi; Guo, Zhi-Xin; Oshiyama, Atsushi

    2017-12-01

    We develop a new position-resolved band-unfolding method based on the density functional theory to clarify the single-electron energy spectrum of (3 ×3 ) silicene on Ag (111 ) substrate. The position-resolved scheme enables us to clarify each contribution from each spatial region to the single-electron spectrum, which facilitates the chemical identification of each electron state. We find interface states which are distributed in the region of silicene and top two layers of the Ag substrate near the Fermi level and also below the Fermi level. The states are unique in silicene on a substrate in the sense that they are mixtures of Si and Ag orbitals. The obtained electronic structure near the Fermi level is interesting, featuring a hyperbolic-paraboloid-shaped energy band which leads to 12 Dirac-like cones at the boundary of the primitive Brillouin zone of Ag (111 ) . Characteristics of measured photoemission spectra are satisfactorily explained by the obtained unfolded bands.

  3. Simultaneous dual-wavelength-band common-path swept-source optical coherence tomography with single polygon mirror scanner.

    Science.gov (United States)

    Mao, Youxin; Chang, Shoude; Murdock, Erroll; Flueraru, Costel

    2011-06-01

    We report a novel (to the best of our knowledge) simultaneous 1310/1550 two-wavelength band swept laser source and dual-band common-path swept-source optical coherence tomography (SS-OCT). Synchronized dual-wavelength tuning is performed by using two laser cavities and narrowband wavelength filters with a single dual-window polygonal scanner. Measured average output powers of 60 and 27 mW have been achieved for the 1310 and 1550 nm bands, respectively, while the two wavelengths were swept simultaneously from 1227 to 1387 nm for the 1310 nm band and from 1519 to 1581 nm for the 1550 nm band at an A-scan rate of 65 kHz. Broadband wavelength-division multiplexing is used for coupling two wavelengths into a common-path single-mode GRIN-lensed fiber probe to form dual-band common-path SS-OCT. Simultaneous OCT imaging at 1310 and 1550 nm is achieved. This technique allows for in vivo high-speed OCT imaging with potential application in functional (spectroscopic) investigations. © 2011 Optical Society of America

  4. Spin-dependent electron-phonon coupling in the valence band of single-layer WS2

    DEFF Research Database (Denmark)

    Hinsche, Nicki Frank; Ngankeu, Arlette S.; Guilloy, Kevin

    2017-01-01

    The absence of inversion symmetry leads to a strong spin-orbit splitting of the upper valence band of semiconducting single-layer transition-metal dichalchogenides such as MoS2 or WS2. This permits a direct comparison of the electron-phonon coupling strength in states that only differ by their spin....... Here, the electron-phonon coupling in the valence band maximum of single-layer WS2 is studied by first-principles calculations and angle-resolved photoemission. The coupling strength is found to be drastically different for the two spin-split branches, with calculated values of λK=0.0021 and 0.......40 for the upper and lower spin-split valence band of the freestanding layer, respectively. This difference is somewhat reduced when including scattering processes involving the Au(111) substrate present in the experiment but it remains significant, in good agreement with the experimental results....

  5. A Novel Compact Ultra-Wideband Antenna with Single and Double Band Rejection

    Directory of Open Access Journals (Sweden)

    B. Zakeri

    2014-12-01

    Full Text Available Band-notch characteristic has been of great interest recently to overcome the electromagnetic interference of Ultra-wideband systems (UWB with other existing ones. In this paper, we present a novel microstrip-fed antenna with band rejection property appropriate for UWB applications. Band-notch characteristic has been achieved by adding a rectangular resonant element to the ground section. A prototype was fabricated and measured based upon optimal parameters. Experimental results show consistency with simulation results. Measurement results confirm that the antenna covers the UWB band and satisfies a band rejection in the frequency span of 5 GHz to 5.7 GHz to restrain it from interference with Wireless Local Area Network (WLAN. Then, to achieve better isolation, a rectangular strip is appended to the band-notch creating part of the ground section to enhance obtained VSWR up to 30 through simulation. In addition, by applying a similar technique, a dual band-notched characteristic with an average simulated VSWR of around 13.75 has been achieved for WLAN and the downlink of X band satellite communication systems with each more than 10. Features such as small size, omnidirectional pattern and perfect isolation make the antenna suitable for any UWB applications.

  6. Long-range spin-singlet proximity effect for a Josephson system with a single-crystal ferromagnet due to its band-structure features

    Science.gov (United States)

    Avdeev, M. V.; Proshin, Yu. N.

    2018-03-01

    A possible explanation for the long-range proximity effect observed in single-crystalline cobalt nanowires sandwiched between two tungsten superconducting electrodes [Nat. Phys. 6, 389 (2010), 10.1038/nphys1621] is proposed. The theoretical model uses properties of a ferromagnet band structure. Specifically, to connect the exchange field with the momentum of quasiparticles the distinction between the effective masses in majority and minority spin subbands and the Fermi-surface anisotropy are considered. The derived Eilenberger-like equations allowed us to obtain a renormalized exchange interaction that is completely compensated for some crystallographic directions under certain conditions. The proposed theoretical model is compared with previous approaches.

  7. De Hass-van Alphen and magnetoresistance reveal predominantly single-band transport behavior in PdTe2.

    Science.gov (United States)

    Wang, Yongjian; Zhang, Jinglei; Zhu, Wenka; Zou, Youming; Xi, Chuanying; Ma, Long; Han, Tao; Yang, Jun; Wang, Jingrong; Xu, Junmin; Zhang, Lei; Pi, Li; Zhang, Changjin; Zhang, Yuheng

    2016-08-12

    Research on two-dimensional transition metal dichalcogenides (TMDs) has grown rapidly over the past several years, from fundamental studies to the development of next generation technologies. Recently, it has been reported that the MX2-type PdTe2 exhibits superconductivity with topological surface state, making this compound a promising candidate for investigating possible topological superconductivity. However, due to the multi-band feature of most of TMDs, the investigating of magnetoresistance and quantum oscillations of these TMDs proves to be quite complicated. Here we report a combined de Hass-van Alphen effect and magnetoresistance studies on the PdTe2 single crystal. Our high-field de Hass-van Alphen data measured at different temperature and different tilting angle suggest that though these is a well-defined multi-band feature, a predominant oscillation frequency has the largest oscillation magnitude in the fast Fourier transformation spectra, which is at least one order of magnitude larger than other oscillation frequencies. Thus it is likely that the transport behavior in PdTe2 system can be simplified into a single-band model. Meanwhile, the magnetoresistance results of the PdTe2 sample can be well-fitted according to the single-band models. The present results could be important in further investigation of the transport behaviors of two-dimensional TMDs.

  8. A single-patterned five-band terahertz metamaterial absorber based on multiple resonance mechanisms

    Science.gov (United States)

    Ju, Zong-De; Xu, Guo-Qing; Wei, Zhi-Hua; Li, Jing; Zhao, Qian; Huang, Jie

    2018-01-01

    A single-patterned five-band terahertz metamaterial absorber based on simple metal-dielectric-metal sandwich structure is investigated and demonstrated. The numerical simulations reveal the different dependence of the absorption ability on the incident polarization angle, dielectric layer, and structural dimensions of the single pattern. The extracted electric field distribution indicates that the five-band near-perfect absorption performance (average over 98%) mainly originates from the combination of LC, dipole, quadrupole, and high-order resonance. The researches on magnetic field and power loss density distributions further reveal the absorption mechanism. Moreover, additional resonance mode can be excited to form a six-band high-performance absorber only by adjusting some geometric dimensions of the single pattern with multiple resonance modes. The simple method provides us a very good idea to implement a super multi-band absorber. The proposed absorbers here can be applied in massive related fields, such as metamaterial sensors, thermal radiation, and imaging system.

  9. Intrinsic single-band upconversion emission in colloidal Yb/Er(Tm):Na3Zr(Hf)F7 nanocrystals.

    Science.gov (United States)

    Chen, Daqin; Lei, Lei; Zhang, Rui; Yang, Anping; Xu, Ju; Wang, Yuansheng

    2012-11-07

    Novel Yb/Er(Tm):Na(3)MF(7) (M = Zr, Hf) nanocrystals with intrinsic single-band upconversion emission, in contrast to the routine lanthanide-doped fluoride nanocrystals which show typical multi-band upconversion emissions, are reported for the first time. Specifically, the red upconversion intensity of the Yb/Er:Na(3)ZrF(7) nanocrystals is about 5 times as high as that of the hexagonal Yb/Er:NaYF(4) ones with a similar crystal size.

  10. A Planar UWB Antenna with Switchable Single/Double Band-Rejection Characteristics

    Directory of Open Access Journals (Sweden)

    V. Sharbati

    2016-09-01

    Full Text Available In this Paper, a reconfigurable antenna with capability to operate in the ultrawideband (UWB mode from 2.85 to 14.4 GHz with switchable notch bands of 3.25–4.26 GHz, 5.1–5.9 GHz or 7.1-7.8 GHz, is presented. The proposed antenna has a simple configuration and compact size of 17 × 14 mm2. To make the band-notches, three methods (methods of slot antenna, parasitic patches and backplane structure are used. To achieve the reconfigurability, three PIN diode are placed on the proposed antenna. A PIN diode is inserted over the L-shaped parasitic element and the rectangular patch, another one is placed between the two parasitic elements on the ground plane, and other across the square ring-shaped slot, respectively. Antenna performance can be changed by adjusting the status of the PIN diodes that make the band-notches in applications bands (WLAN, WiMAX/C-band and X-band. Good group delay and monopole-like radiation pattern characteristics are achieved in the frequency band of interest. The antenna performance both by simulation and by experiment indicates that it is suitable and a good candidate for UWB applications.

  11. Use of GPS TEC Maps for Calibrating Single Band VLBI Sessions

    Science.gov (United States)

    Gordon, David

    2010-01-01

    GPS TEC ionosphere maps were first applied to a series of K and Q band VLBA astrometry sessions to try to eliminate a declination bias in estimated source positions. Their usage has been expanded to calibrate X-band only VLBI observations as well. At K-band, approx.60% of the declination bias appears to be removed with the application of GPS ionosphere calibrations. At X-band however, it appears that up to 90% or more of the declination bias is removed, with a corresponding increase in RA and declination uncertainties of approx.0.5 mas. GPS ionosphere calibrations may be very useful for improving the estimated positions of the X-only and S-only sources in the VCS and RDV sessions.

  12. Determination of band alignment in the single-layer MoS2/WSe2 heterojunction

    KAUST Repository

    Chiu, Ming-Hui

    2015-07-16

    The emergence of two-dimensional electronic materials has stimulated proposals of novel electronic and photonic devices based on the heterostructures of transition metal dichalcogenides. Here we report the determination of band offsets in the heterostructures of transition metal dichalcogenides by using microbeam X-ray photoelectron spectroscopy and scanning tunnelling microscopy/spectroscopy. We determine a type-II alignment between MoS2 and WSe2 with a valence band offset value of 0.83 eV and a conduction band offset of 0.76 eV. First-principles calculations show that in this heterostructure with dissimilar chalcogen atoms, the electronic structures of WSe2 and MoS2 are well retained in their respective layers due to a weak interlayer coupling. Moreover, a valence band offset of 0.94 eV is obtained from density functional theory, consistent with the experimental determination.

  13. Slip-band formation and dislocation kinetics in the stage I deformation of neutron-irradiated copper single crystals

    International Nuclear Information System (INIS)

    Kitajima, Sadakichi; Shinohara, Kazutoshi; Kutsuwada, Masanori

    1995-01-01

    The velocity of edge and screw dislocations moving in primary slip bands and the formation rate of primary slip bands were measured in stage I deformation of neutron-irradiated copper single crystals at different strain rates at room temperature using micro-cinematography and optical micrography. The average velocity of edge dislocations was larger at least by one order than that of screw ones, and that of screw dislocations did not depend so strongly on strain rate. The formation rate of primary slip bands was proportional to strain rate. From these results, it is concluded that (1) jogs produced on moving dislocations by cutting dislocation loops result in the difference in velocity between edge and screw dislocations and (2) the change in the density of mobile dislocations as well as velocity of dislocations is responsible for the change of plastic strain rate of a crystal. (author)

  14. Single-mode optical fiber design with wide-band ultra low bending-loss for FTTH application.

    Science.gov (United States)

    Watekar, Pramod R; Ju, Seongmin; Han, Won-Taek

    2008-01-21

    We propose a new design of a single-mode optical fiber (SMF) which exhibits ultra low bend sensitivity over a wide communication band (1.3 microm to 1.65 microm). A five-cladding fiber structure has been proposed to minimize the bending loss, estimated to be as low as 4.4x10(-10) dB/turn for the bend radius of 10 mm.

  15. Single and Multipolarimetric P-Band SAR Tomography of Subsurface Ice Structure

    DEFF Research Database (Denmark)

    Banda, Francesco; Dall, Jørgen; Tebaldini, Stefano

    2016-01-01

    Agency IceSAR 2012 campaign is discussed. IceSAR 2012 was conceived so as to support the secondary objectives of the future Earth Explorer mission BIOMASS, which will be a SAR instrument with media penetration capabilities due to the use of the P-band frequency. In this regard, a tomographic study of ice...

  16. Homogeneity of Surface Sites in Supported Single-Site Metal Catalysts: Assessment with Band Widths of Metal Carbonyl Infrared Spectra.

    Science.gov (United States)

    Hoffman, Adam S; Fang, Chia-Yu; Gates, Bruce C

    2016-10-06

    Determining and controlling the uniformity of isolated metal sites on surfaces of supports are central goals in investigations of single-site catalysts because well-defined species provide opportunities for fundamental understanding of the surface sites. CO is a useful probe of surface metal sites, often reacting with them to form metal carbonyls, the infrared spectra of which provide insights into the nature of the sites and the metal-support interface. Metals bonded to various support surface sites give broad bands in the spectra, and when narrow bands are observed, they indicate a high degree of uniformity of the metal sites. Much recent work on single-site catalysts has been done with supports that are inherently nonuniform, giving supported metal species that are therefore nonuniform. Herein we summarize values of ν CO data characterizing supported iridium gem-dicarbonyls, showing that the most nearly uniform of them are those supported on zeolites and the least uniform are those supported on metal oxides. Guided by ν CO data of supported iridium gem-dicarbonyls, we have determined new, general synthesis methods to maximize the degree of uniformity of iridium species on zeolites and on MgO. We report results for a zeolite HY-supported iridium gem-dicarbonyl with full width at half-maximum values of only 4.6 and 5.2 cm -1 characterizing the symmetric and asymmetric CO stretches and implying that this is the most nearly uniform supported single-site metal catalyst.

  17. Single-session treatment of a major complication of dens invaginatus: a case report.

    Science.gov (United States)

    Caldari, Mauro; Monaco, Carlo; Ciocca, Leonardo; Scotti, Roberto

    2006-05-01

    Dens invaginatus is a dental malformation that may give rise to several complications. Caries of the invagination can severely weaken the whole tooth, making it susceptible to fracture. Subgingival fractures are major complications threatening tooth survival and usually require periodontal/orthodontic/prosthetic treatment if long-term viability is to be ensured. This article describes a case of single-session restoration of a fractured invaginated tooth by means of endodontic treatment followed by fragment reattachment.

  18. The effect of a low-frequency noise signal on a single-frequency millimeter-band oscillator based on an avalanche-transit diode

    Science.gov (United States)

    Kotov, V. D.; Myasin, E. A.

    2017-11-01

    Noise-wave generation in a single-frequency oscillator based on a 7-mm-band avalanche-transit diode has been implemented for the first time under the action of a low-frequency narrow-band ( 3 MHz) noise signal on an avalanche-transit-diode feed circuit.

  19. Conduction band mass determinations for n-type InGaAs/InAlAs single quantum wells

    Energy Technology Data Exchange (ETDEWEB)

    Jones, E.D.; Reno, J.L. [Sandia National Labs., Albuquerque, NM (United States); Kotera, Nobuo [Kyushu Inst. of Tech., Iizuka, Fukuoka (Japan); Wang, Y. [Florida State Univ., Tallahassee, FL (United States). National High Magnetic Field Lab.

    1998-05-01

    The authors report the measurement of the conduction band mass in n-type single 27-ML-wide InGaAs/InAlAs quantum well lattice matched to InP using two methods: (1) Magnetoluminescence spectroscopy and (2) far-infrared cyclotron resonance. The magnetoluminescence method utilizes Landau level transitions between 0 and 14 T at 1.4 K. The far infrared cyclotron resonance measurements were made at 4.2 K and to fields as large up to 18 T. The 2D-carrier density N{sub 2D} = 3 {times} 10{sup 11} cm{sup {minus}2} at low temperatures. The magnetoluminescence technique yielded an effective conduction-band mass of m{sub c} = 0.062m{sub 0} while the far infrared cyclotron resonance measurements gave m{sub c} = 0.056m{sub 0}, where m{sub 0} is the free electron mass. Both measurements show no evidence for any significant conduction-band nonparabolicity.

  20. Telecommunication Wavelength-Band Single-Photon Emission from Single Large InAs Quantum Dots Nucleated on Low-Density Seed Quantum Dots.

    Science.gov (United States)

    Chen, Ze-Sheng; Ma, Ben; Shang, Xiang-Jun; He, Yu; Zhang, Li-Chun; Ni, Hai-Qiao; Wang, Jin-Liang; Niu, Zhi-Chuan

    2016-12-01

    Single-photon emission in the telecommunication wavelength band is realized with self-assembled strain-coupled bilayer InAs quantum dots (QDs) embedded in a planar microcavity on GaAs substrate. Low-density large QDs in the upper layer active for ~1.3 μm emission are fabricated by precisely controlling the indium deposition amount and applying a gradient indium flux in both QD layers. Time-resolved photoluminescence (PL) intensity suggested that the radiative lifetime of their exciton emission is 1.5~1.6 ns. The second-order correlation function of g (2)(0) < 0.5 which demonstrates a pure single-photon emission.

  1. An Improved Single-Channel Method to Retrieve Land Surface Temperature from the Landsat-8 Thermal Band

    Directory of Open Access Journals (Sweden)

    Jordi Cristóbal

    2018-03-01

    Full Text Available Land surface temperature (LST is one of the sources of input data for modeling land surface processes. The Landsat satellite series is the only operational mission with more than 30 years of archived thermal infrared imagery from which we can retrieve LST. Unfortunately, stray light artifacts were observed in Landsat-8 TIRS data, mostly affecting Band 11, currently making the split-window technique impractical for retrieving surface temperature without requiring atmospheric data. In this study, a single-channel methodology to retrieve surface temperature from Landsat TM and ETM+ was improved to retrieve LST from Landsat-8 TIRS Band 10 using near-surface air temperature (Ta and integrated atmospheric column water vapor (w as input data. This improved methodology was parameterized and successfully evaluated with simulated data from a global and robust radiosonde database and validated with in situ data from four flux tower sites under different types of vegetation and snow cover in 44 Landsat-8 scenes. Evaluation results using simulated data showed that the inclusion of Ta together with w within a single-channel scheme improves LST retrieval, yielding lower errors and less bias than models based only on w. The new proposed LST retrieval model, developed with both w and Ta, yielded overall errors on the order of 1 K and a bias of −0.5 K validated against in situ data, providing a better performance than other models parameterized using w and Ta or only w models that yielded higher error and bias.

  2. Decay of superdeformed bands

    International Nuclear Information System (INIS)

    Carpenter, M.P.; Khoo, T.L.; Lauritsen, T.

    1995-01-01

    One of the major challenges in the study of superdeformation is to directly connect the large number of superdeformed bands now known to the yrast states. In this way, excitation energies, spins and parities can be assigned to the levels in the second well which is essential to establish the collective and single-particle components of these bands. This paper will review some of the progress which has been made to understand the decay of superdeformed bands using the new arrays including the measurement of the total decay spectrum and the establishment of direct one-step decays from the superdeformed band to the yrast line in 194 Hg. 42 refs., 5 figs

  3. X-band singly degenerate parametric amplification in a Josephson tunnel junction

    DEFF Research Database (Denmark)

    Mygind, Jesper; Pedersen, Niels Falsig; Sørensen, O. H.

    1978-01-01

    Preliminary measurements on a (quasi-) degenerate parametric amplifier using a single Josephson tunnel junction as the active element is reported. The pump frequency is at 18 GHz and the signal and idler frequencies are both at about 9 GHz. A power gain of 16 dB in a 4-MHz 3-dB bandwidth is achie...... is achieved at the top of the cryostat. Applied Physics Letters is copyrighted by The American Institute of Physics....

  4. single crystal growth, x-ray structure analysis, optical band gap

    African Journals Online (AJOL)

    2015-09-01

    Sep 1, 2015 ... Hg...Hgand Cl...Cl interactions are stabilizing the structures in 3D pattern. UV-vis absorption spectra illustrate the change in opticalband gap from 3.01eVto 3.42eV on replacing the metal halide group.Raman and Hyper-Raman tensors calculations were performed based on single crystal X-ray data and the ...

  5. Single-stage revision from gastric band to gastric bypass or sleeve gastrectomy: 6- and 12-month outcomes.

    Science.gov (United States)

    Yeung, Louise; Durkan, Brandice; Barrett, Allison; Kraft, Cary; Vu, Kim; Phillips, Edward; Cunneen, Scott; Burch, Miguel

    2016-06-01

    Laparoscopic adjustable gastric banding (LAGB) is increasingly requiring revisional surgery for complications and failures. Removal of the band and conversion to either laparoscopic Roux-en-y gastric bypass (LRYGB) or laparoscopic sleeve gastrectomy (LSG) is feasible as a single-stage procedure. The objective of this study is to compare the safety and efficacy of single-stage revision from LAGB to either LRYGB or LSG at 6 and 12 months postoperatively. Retrospective analysis was performed on patients undergoing single-stage revision between 2009 and 2014 at a single academic medical center. Patients were reassessed for weight loss and complications at 6 and 12 months postoperatively. Thirty-two patients underwent single-stage revision to LRYGB, and 72 to LSG. Preoperative BMIs were similar between the two groups (p = 0.27). Median length of stay for LRYGB was 3 days versus 2 for LSG (p = 0.14). Four patients in the LRYGB group required reoperation within 30 days, and two patients in the LSG group required reoperation within 30 days (p = 0.15). There was no difference in ER visits (p = 0.24) or readmission rates (p = 0.80) within 30 days of operation. Six delayed complications were seen in the LSG group with three requiring intervention. At 6 months postoperatively, percent excess weight loss (%EWL) was 50.20 for LRYGB and 30.64 for LSG (p = 0.056). At 12 months, %EWL was 51.19 for LRYGB and 34.89 for LSG (p = 0.31). There was no difference in diabetes or hypertension medication reduction at 12 months between LRYGB and LSG (p > 0.07). Single-stage revision from LAGB to LRYGB or LSG is technically feasible, but not without complications. The complications in the bypass group were more severe. There was no difference in readmission or reoperation rates, weight loss or comorbidity reduction. Revision to LRYGB trended toward higher rate and greater severity of complications with equivalent weight loss and comorbidity reduction.

  6. Source heterogeneity for the major components of ~3.7 Ga banded iron formations (Isua Greenstone Belt, Western Greenland)

    DEFF Research Database (Denmark)

    Frei, Robert; Polat, Ali

    2006-01-01

    We report trace element, samarium (Sm)-neodymium (Nd) and lead (Pb) isotopic data for individual micro-and mesobands of the Earth's oldest Banded Iron Formation (BIF) from the  3.7-3.8 Ga Isua Greenstone Belt (IGB, West Greenland) in an attempt to contribute to the characterization of the deposit......We report trace element, samarium (Sm)-neodymium (Nd) and lead (Pb) isotopic data for individual micro-and mesobands of the Earth's oldest Banded Iron Formation (BIF) from the  3.7-3.8 Ga Isua Greenstone Belt (IGB, West Greenland) in an attempt to contribute to the characterization......-Nd isotopic relations on a layer-by-layer basis point to two REE sources controlling the back-arc basin depositional environment of the BIF, one being seafloor-vented hydrothermal fluids (eNd (3.7 Ga)   + 3.1), the other being ambient surface seawater which reached its composition by erosion of parts...... of the protocrustal landmass (eNd(3.7 Ga)   + 1.6). The validity of two different and periodically interacting water masses (an essentially two-component mixing system) in the deposition of alternating iron- and silica-rich layers is also reflected by systematic trends in germanium (Ge)/silicon (Si) ratios...

  7. Laparoscopic Adjustable Gastric Banding: Predictive Factors for Weight Loss and Band Removal After More than 10 Years' Follow-Up in a Single University Unit.

    Science.gov (United States)

    Tammaro, Pasquale; Hansel, Boris; Police, Andrea; Kousouri, Marina; Magnan, Christophe; Marmuse, Jean Pierre; Arapis, Konstantinos

    2017-08-01

    Weight loss and overall outcomes following laparoscopic adjustable gastric banding (LAGB) are more variable than with other bariatric procedures. Our aim was to investigate the predictive value of certain parameters in a cohort of 794 patients with 10 years' minimum follow-up after LAGB. We retrospectively reviewed the records of 794 patients undergoing LAGB performed by the authors between April 1996 and December 2004. We collected patients' data on weight loss and band-related complications and performed logistic regression modelling and calculated Kaplan-Meier curves for band preservation. The follow-up rate at 10 years was 90.4%. The mean follow-up duration was 15.1 years (range, 120-228 months). Overall band removal with or without conversion or replacement was required in 304 (38.2%) patients. The mean survival time of the band was 148.4 months (95% confidence interval: 138.3-167.4), and there was no difference in the rate of removal by operative technique (p = 0.7). The highest rate of band removal occurred in female patients (p = 0.05), those with BMI > 50 kg/m 2 (p = 0.005) and in those success rate was significantly lower in patients with initial BMI > 50 kg/m 2 . Conversely, differences in success rate were not statistically significant for age (using 50 years as the cut-off), technique or sex. Higher rates of removal occurred in women, younger patients and those with BMI > 50 kg/m 2 . Regardless of these criteria, the rate of band removal for complications rose over time. Patients should be informed of the high risk of the need for band removal long-term.

  8. Tuning the band structure and superconductivity in single-layer FeSe by interface engineering.

    Science.gov (United States)

    Peng, R; Xu, H C; Tan, S Y; Cao, H Y; Xia, M; Shen, X P; Huang, Z C; Wen, C H P; Song, Q; Zhang, T; Xie, B P; Gong, X G; Feng, D L

    2014-09-26

    The interface between transition metal compounds provides a rich playground for emergent phenomena. Recently, significantly enhanced superconductivity has been reported for single-layer FeSe on Nb-doped SrTiO3 substrate. Yet it remains mysterious how the interface affects the superconductivity. Here we use in situ angle-resolved photoemission spectroscopy to investigate various FeSe-based heterostructures grown by molecular beam epitaxy, and uncover that electronic correlations and superconducting gap-closing temperature (Tg) are tuned by interfacial effects. Tg up to 75 K is observed in extremely tensile-strained single-layer FeSe on Nb-doped BaTiO3, which sets a record high pairing temperature for both Fe-based superconductor and monolayer-thick films, providing a promising prospect on realizing more cost-effective superconducting device. Moreover, our results exclude the direct correlation between superconductivity and tensile strain or the energy of an interfacial phonon mode, and highlight the critical and non-trivial role of FeSe/oxide interface on the high Tg, which provides new clues for understanding its origin.

  9. Ewald sphere correction using a single side-band image processing algorithm.

    Science.gov (United States)

    Russo, Christopher J; Henderson, Richard

    2018-04-01

    Curvature of the Ewald sphere limits the resolution at which Fourier components in an image can be approximated as corresponding to a projection of the object. Since the radius of the Ewald sphere is inversely proportional to the wavelength of the imaging electrons, this normally imposes a limit on the thickness of specimen for which images can be easily interpreted to a particular resolution. Here we present a computational method for precisely correcting for the curvature of the Ewald sphere using defocused images that delocalise the high-resolution Fourier components from the primary image. By correcting for each approximately Friedel-symmetry-related sideband separately using two distinct complex transforms that effectively move the displaced Fourier components back to where they belong in the structure, we can determine the amplitude and phase of each of the Fourier components separately. This precisely accounts for the effect of Ewald sphere curvature over a bandwidth defined by the defocus and the size of the particle being imaged. We demonstrate this processing algorithm using: 1. simulated images of a particle with only a single, high-resolution Fourier component, and 2. experimental images of gold nanoparticles embedded in ice. Processing micrographs with this algorithm will allow higher resolution imaging of thicker specimens at lower energies without any image degradation or blurring due to errors made by the assumption of a flat Ewald sphere. Although the procedure will work best on images recorded with higher defocus settings than used normally, it should still improve 3D single-particle structure determination using images recorded at any defocus and any electron energy. Finally, since the Ewald sphere curvature is in a known direction in the third dimension which is parallel to the direction of view, this algorithm automatically determines the absolute hand of the specimen without the need for pairs of images with a known tilt angle difference

  10. Axial-Compressive Behavior, Including Kink-Band Formation and Propagation, of Single p-Phenylene Terephthalamide (PPTA Fibers

    Directory of Open Access Journals (Sweden)

    M. Grujicic

    2013-01-01

    Full Text Available The mechanical response of p-phenylene terephthalamide (PPTA single fibers when subjected to uniaxial compression is investigated computationally using coarse-grained molecular statics/dynamics methods. In order to construct the coarse-grained PPTA model (specifically, in order to define the nature of the coarse-grained particles/beads and to parameterize various components of the bead/bead force-field functions, the results of an all-atom molecular-level computational investigation are used. In addition, the microstructure/topology of the fiber core, consisting of a number of coaxial crystalline fibrils, is taken into account. Also, following our prior work, various PPTA crystallographic/topological defects are introduced into the model (at concentrations consistent with the prototypical PPTA synthesis/processing conditions. The analysis carried out clearly revealed (a formation of the kink bands during axial compression; (b the role of defects in promoting the formation of kink bands; (c the stimulating effects of some defects on the fiber-fibrillation process; and (d the detrimental effect of the prior compression, associated with fiber fibrillation, on the residual longitudinal-tensile strength of the PPTA fibers.

  11. Narrow band imaging (NBI cystoscopy and assisted bipolar TURBT: A preliminary experience in a single centre

    Directory of Open Access Journals (Sweden)

    Roberto Giulianelli

    2017-10-01

    Full Text Available Objective: The aim of this study was to compare, in order to increase our ability to detect bladder cancer, the predictive power of narrow band imaging (NBI versus white light cystoscopy (WL. The secondary objective was to evaluate how the preoperative use of NBI cystoscopy can increase the ability to detect bladder lesions in terms of status, multi-focality and dimensions. Materials and methods: Between June 2010 and April 2012, 797 consecutive patients, 423 male and 374 female, affected by suspected bladder cancer lesions, underwent to WL plus NBI cystoscopy and subsequently to WL Bipolar Gyrus PK (Olympus, Tokyo, Japan transurethral resection of bladder tumour (WL-TURBT. The average follow-up was 24 (16-38 months. Mean age was 67.7 yrs. (range 46-88. All the patients underwent by same surgeon to WL resection (WL-TURBT of the previously identified lesions by same surgeon. All the removed tissue was sent separately for histological evaluation after mapping the areas of resection on a topographic sheet. Results: In our study we considered 797 patients that matched our inclusion criteria. Through the use of WL cystoscopy, we identified 603 patients (75.53% with suspicious lesions, instead, with the use of light NBI, we found 786 patients with suspicious lesions (98.49%.The use of NBI cystoscopy increases by approximately 30% the specific ability to detect lesions not otherwise visible with WL cystoscopy (OR 21.9 and RR 1.30, in particular for patients with lesions size < 3 cm (OR 24.00; RR 1.40, unifocal (OR: 22.28; RR 1.47 and recurrent (OR 58.4; RR 1.34. Pathology demonstrated the presence of cancer in 512 (64.2% patients, of whom 412 (51.8% were visible both with WL cystoscopy and NBI cystoscopy. In our experience, only 11 (1.38% lesions were only positive at WL cystoscopy (negative at NBI cystoscopy thus 501 (62.8%, OR 10.13; RR 1.21 patients showed bladder oncological lesions positive at NBI cystoscopy. In these patients, the use the NBI

  12. Brain perfusion single photon emission computed tomography in major psychiatric disorders: From basics to clinical practice

    International Nuclear Information System (INIS)

    Santra, Amburanjan; Kumar, Rakesh

    2014-01-01

    Brain single photon emission computed tomography (SPECT) is a well-established and reliable method to assess brain function through measurement of regional cerebral blood flow (rCBF). It can be used to define a patient's pathophysiological status when neurological or psychiatric symptoms cannot be explained by anatomical neuroimaging findings. Though there is ample evidence validating brain SPECT as a technique to track human behavior and correlating psychiatric disorders with dysfunction of specific brain regions, only few psychiatrists have adopted brain SPECT in routine clinical practice. It can be utilized to evaluate the involvement of brain regions in a particular patient, to individualize treatment on basis of SPECT findings, to monitor the treatment response and modify treatment, if necessary. In this article, we have reviewed the available studies in this regard from existing literature and tried to present the evidence for establishing the clinical role of brain SPECT in major psychiatric illnesses

  13. Feelings of worthlessness during a single complicated major depressive episode predict postremission suicide attempt.

    Science.gov (United States)

    Wakefield, J C; Schmitz, M F

    2016-04-01

    To establish which symptoms of major depressive episode (MDE) predict postremission suicide attempts in complicated single-episode cases. Using the nationally representative two-wave National Epidemiologic Survey on Alcohol and Related Conditions data set, we identified wave 1 lifetime single-episode MDE cases in which the episode remitted by the beginning of the wave 2 three-year follow-up period (N = 2791). The analytic sample was further limited to 'complicated' cases (N = 1872) known to have elevated suicide attempt rates, defined as having two or more of the following: suicidal ideation, marked role impairment, feeling worthless, psychomotor retardation, and prolonged (>6 months) duration. Logistic regression analyses showed that, after controlling for wave 1 suicide attempt which significantly predicted postremission suicide attempt (OR = 10.0), the additional complicated symptom 'feelings of worthlessness' during the wave 1 index episode significantly and very substantially predicted postremission suicide attempt (OR = 6.96). Neither wave 1 psychomotor retardation nor wave 1 suicidal ideation nor any of the other wave 1 depressive symptoms were significant predictors of wave 2 suicide attempt. Among depressive symptoms during an MDE, feelings of worthlessness is the only significant indicator of elevated risk of suicide attempt after the episode has remitted, beyond previous suicide attempts. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. Single-molecule analysis of the major glycopolymers of pathogenic and non-pathogenic yeast cells

    Science.gov (United States)

    El-Kirat-Chatel, Sofiane; Beaussart, Audrey; Alsteens, David; Sarazin, Aurore; Jouault, Thierry; Dufrêne, Yves F.

    2013-05-01

    Most microbes are coated with carbohydrates that show remarkable structural variability and play a crucial role in mediating microbial-host interactions. Understanding the functions of cell wall glycoconjugates requires detailed knowledge of their molecular organization, diversity and heterogeneity. Here we use atomic force microscopy (AFM) with tips bearing specific probes (lectins, antibodies) to analyze the major glycopolymers of pathogenic and non-pathogenic yeast cells at molecular resolution. We show that non-ubiquitous β-1,2-mannans are largely exposed on the surface of native cells from pathogenic Candida albicans and C. glabrata, the former species displaying the highest glycopolymer density and extensions. We also find that chitin, a major component of the inner layer of the yeast cell wall, is much more abundant in C. albicans. These differences in molecular properties, further supported by flow cytometry measurements, may play an important role in strengthening cell wall mechanics and immune interactions. This study demonstrates that single-molecule AFM, combined with immunological and fluorescence methods, is a powerful platform in fungal glycobiology for probing the density, distribution and extension of specific cell wall glycoconjugates. In nanomedicine, we anticipate that this new form of AFM-based nanoglycobiology will contribute to the development of sugar-based drugs, immunotherapeutics, vaccines and diagnostics.

  15. Z-band Alternatively Spliced PDZ Motif Protein (ZASP) Is the Major O-Linked β-N-Acetylglucosamine-substituted Protein in Human Heart Myofibrils*

    Science.gov (United States)

    Leung, Man-Ching; Hitchen, Paul G.; Ward, Douglas G.; Messer, Andrew E.; Marston, Steven B.

    2013-01-01

    We studied O-linked β-N-acetylglucosamine (O-GlcNAc) modification of contractile proteins in human heart using SDS-PAGE and three detection methods: specific enzymatic conjugation of O-GlcNAc with UDP-N-azidoacetylgalactosamine (UDP-GalNAz) that is then linked to a tetramethylrhodamine fluorescent tag and CTD110.6 and RL2 monoclonal antibodies to O-GlcNAc. All three methods showed that O-GlcNAc modification was predominantly in a group of bands ∼90 kDa that did not correspond to any of the major myofibrillar proteins. MALDI-MS/MS identified the 90-kDa band as the protein ZASP (Z-band alternatively spliced PDZ motif protein), a minor component of the Z-disc (about 1 per 400 α-actinin) important for myofibrillar development and mechanotransduction. This was confirmed by the co-localization of O-GlcNAc and ZASP in Western blotting and by immunofluorescence microscopy. O-GlcNAcylation of ZASP increased in diseased heart, being 49 ± 5% of all O-GlcNAc in donor, 68 ± 9% in end-stage failing heart, and 76 ± 6% in myectomy muscle samples (donor versus myectomy p heart myofibrils. PMID:23271734

  16. Excitons and trions in monolayer transition metal dichalcogenides: A comparative study between the multiband model and the quadratic single-band model

    Science.gov (United States)

    Van der Donck, M.; Zarenia, M.; Peeters, F. M.

    2017-07-01

    The electronic and structural properties of excitons and trions in monolayer transition metal dichalcogenides are investigated using both a multiband and a single-band model. In the multiband model we construct the excitonic Hamiltonian in the product base of the single-particle states at the conduction and valence band edges. We decouple the corresponding energy eigenvalue equation and solve the resulting differential equation self-consistently, using the finite element method (FEM), to determine the energy eigenvalues and the wave functions. As a comparison, we also consider the simple single-band model which is often used in numerical studies. We solve the energy eigenvalue equation using the FEM as well as with the stochastic variational method (SVM) in which a variational wave function is expanded in a basis of a large number of correlated Gaussians. We find good agreement between the results of both methods, as well as with other theoretical works for excitons, and we also compare with available experimental data. For trions the agreement between both methods is not as good due to our neglect of angular correlations when using the FEM. Finally, when comparing the two models, we see that the presence of the valence bands in the mutiband model leads to differences with the single-band model when (interband) interactions are strong.

  17. High performance of low band gap polymer-based ambipolar transistor using single-layer graphene electrodes.

    Science.gov (United States)

    Choi, Jong Yong; Kang, Woonggi; Kang, Boseok; Cha, Wonsuk; Son, Seon Kyoung; Yoon, Youngwoon; Kim, Hyunjung; Kang, Youngjong; Ko, Min Jae; Son, Hae Jung; Cho, Kilwon; Cho, Jeong Ho; Kim, BongSoo

    2015-03-18

    Bottom-contact bottom-gate organic field-effect transistors (OFETs) are fabricated using a low band gap pDTTDPP-DT polymer as a channel material and single-layer graphene (SLG) or Au source/drain electrodes. The SLG-based ambipolar OFETs significantly outperform the Au-based ambipolar OFETs, and thermal annealing effectively improves the carrier mobilities of the pDTTDPP-DT films. The difference is attributed to the following facts: (i) the thermally annealed pDTTDPP-DT chains on the SLG assume more crystalline features with an edge-on orientation as compared to the polymer chains on the Au, (ii) the morphological features of the thermally annealed pDTTDPP-DT films on the SLG electrodes are closer to the features of those on the gate dielectric layer, and (iii) the SLG electrode provides a flatter, more hydrophobic surface that is favorable for the polymer crystallization than the Au. In addition, the preferred carrier transport in each electrode-based OFET is associated with the HOMO/LUMO alignment relative to the Fermi level of the employed electrode. All of these experimental results consistently explain why the carrier mobilities of the SLG-based OFET are more than 10 times higher than those of the Au-based OTFT. This work demonstrates the strong dependence of ambipolar carrier transport on the source/drain electrode and annealing temperature.

  18. Spiral magnetism in the single-band Hubbard model: the Hartree-Fock and slave-boson approaches.

    Science.gov (United States)

    Igoshev, P A; Timirgazin, M A; Gilmutdinov, V F; Arzhnikov, A K; Irkhin, V Yu

    2015-11-11

    The ground-state magnetic phase diagram is investigated within the single-band Hubbard model for square and different cubic lattices. The results of employing the generalized non-correlated mean-field (Hartree-Fock) approximation and generalized slave-boson approach by Kotliar and Ruckenstein with correlation effects included are compared. We take into account commensurate ferromagnetic, antiferromagnetic, and incommensurate (spiral) magnetic phases, as well as phase separation into magnetic phases of different types, which was often lacking in previous investigations. It is found that the spiral states and especially ferromagnetism are generally strongly suppressed up to non-realistically large Hubbard U by the correlation effects if nesting is absent and van Hove singularities are well away from the paramagnetic phase Fermi level. The magnetic phase separation plays an important role in the formation of magnetic states, the corresponding phase regions being especially wide in the vicinity of half-filling. The details of non-collinear and collinear magnetic ordering for different cubic lattices are discussed.

  19. Atmospheric extinction coefficient retrieval and validation for the single-band Mie-scattering Scheimpflug lidar technique.

    Science.gov (United States)

    Mei, Liang; Guan, Peng; Yang, Yang; Kong, Zheng

    2017-08-07

    An 808 nm single-band Mie scattering Scheimpflug lidar system is developed in Dalian, Northern China, for real-time, large-area atmospheric aerosol/particle remote sensing. Atmospheric measurement has been performed in urban area during a typical haze weather condition, and time-range distribution of atmospheric backscattering signal is recorded from March 18th to 22nd, 2017, by employing the Scheimpflug lidar system. Atmospheric extinction coefficient is then retrieved according to the Klett-inversion algorithm, while the boundary value is obtained by the slope-method in the far end where the atmosphere is homogeneous in a subinterval region. The correlation between the extinction coefficients retrieved from the Scheimpflug lidar technique and the PM10/PM2.5 concentrations measured by a conventional air pollution monitoring station is also studied. The good agreement between the measurement results, i.e., a correlation coefficient of 0.85, successfully demonstrates the feasibility and great potential of the Scheimpflug lidar technique for atmospheric studies and applications.

  20. Conversion of failed laparoscopic adjustable gastric banding to Roux-en-Y gastric bypass is safe as a single-step procedure

    NARCIS (Netherlands)

    Emous, M.; Apers, J.; Hoff, C.; van Beek, A. P.; Totte, E.

    Several different procedures have been proposed as a revisional procedure for treatment of failed laparoscopic adjustable gastric banding (LAGB). Laparoscopic Roux-en-Y gastric bypass (LRYGB) has been advocated as the procedure of choice for revision. In this study, we compare the single- and

  1. Dense cranial electroacupuncture stimulation for major depressive disorder--a single-blind, randomized, controlled study.

    Directory of Open Access Journals (Sweden)

    Zhang-Jin Zhang

    Full Text Available BACKGROUND: Previous studies suggest that electroacupuncture possesses therapeutic benefits for depressive disorders. The purpose of this study was to determine whether dense cranial electroacupuncture stimulation (DCEAS could enhance the antidepressant efficacy in the early phase of selective serotonin reuptake inhibitor (SSRI treatment of major depressive disorder (MDD. METHODS: In this single-blind, randomized, controlled study, patients with MDD were randomly assigned to 9-session DCEAS or noninvasive electroacupuncture (n-EA control procedure in combination with fluoxetine (FLX for 3 weeks. Clinical outcomes were measured using the 17-item Hamilton Depression Rating Scale (HAMD-17, Clinical Global Impression-severity (CGI-S, and Self-rating Depression Scale (SDS as well as the response and remission rates. RESULTS: Seventy-three patients were randomly assigned to n-EA (n = 35 and DCEAS (n = 38, of whom 34 in n-EA and 36 in DCEAS group were analyzed. DCEAS-treated patients displayed a significantly greater reduction from baseline in HAMD-17 scores at Day 3 through Day 21 and in SDS scores at Day 3 and Day 21 compared to patients receiving n-EA. DCEAS intervention also produced a higher rate of clinically significant response compared to n-EA procedure (19.4% (7/36 vs. 8.8% (3/34. The incidence of adverse events was similar in the two groups. CONCLUSIONS: DCEAS is a safe and effective intervention that augments the antidepressant efficacy. It can be considered as an additional therapy in the early phase of SSRI treatment of depressed patients. TRIAL REGISTRATION: Controlled-Trials.com ISRCTN88008690.

  2. Atmospheric Extinction Coefficients in the Ic Band for Several Major International Observatories: Results from the BiSON Telescopes, 1984-2016

    Science.gov (United States)

    Hale, S. J.; Chaplin, W. J.; Davies, G. R.; Elsworth, Y. P.; Howe, R.; Lund, M. N.; Moxon, E. Z.; Thomas, A.; Pallé, P. L.; Rhodes, E. J., Jr.

    2017-09-01

    Over 30 years of solar data have been acquired by the Birmingham Solar Oscillations Network (BiSON), an international network of telescopes used to study oscillations of the Sun. Five of the six BiSON telescopes are located at major observatories. The observational sites are, in order of increasing longitude: Mount Wilson (Hale) Observatory (MWO), California, USA; Las Campanas Observatory, Chile; Observatorio del Teide, Izaña, Tenerife, Canary Islands; the South African Astronomical Observatory, Sutherland, South Africa; Carnarvon, Western Australia; and the Paul Wild Observatory, Narrabri, New South Wales, Australia. The BiSON data may be used to measure atmospheric extinction coefficients in the {{{I}}}{{c}} band (approximately 700-900 nm), and presented here are the derived atmospheric extinction coefficients from each site over the years 1984-2016.

  3. Influence of leaching on surface composition, microstructure, and valence band of single grain icosahedral Al-Cu-Fe quasicrystal

    International Nuclear Information System (INIS)

    Lowe, M.; McGrath, R.; Sharma, H. R.; Yadav, T. P.; Fournée, V.; Ledieu, J.

    2015-01-01

    The use of quasicrystals as precursors to catalysts for the steam reforming of methanol is potentially one of the most important applications of these new materials. To develop application as a technology requires a detailed understanding of the microscopic behavior of the catalyst. Here, we report the effect of leaching treatments on the surface microstructure, chemical composition, and valence band of the icosahedral (i-) Al-Cu-Fe quasicrystal in an attempt to prepare a model catalyst. The high symmetry fivefold surface of a single grain i-Al-Cu-Fe quasicrystal was leached with NaOH solution for varying times, and the resulting surface was characterized by x-ray photoelectron spectroscopy (XPS), ultraviolet photoelectron spectroscopy (UPS), scanning electron microscopy (SEM), and atomic force microscopy (AFM). The leaching treatments preferentially remove Al producing a capping layer consisting of Fe and Cu oxides. The subsurface layer contains elemental Fe and Cu in addition to the oxides. The quasicrystalline bulk structure beneath remains unchanged. The subsurface gradually becomes Fe 3 O 4 rich with increasing leaching time. The surface after leaching exhibits micron sized dodecahedral cavities due to preferential leaching along the fivefold axis. Nanoparticles of the transition metals and their oxides are precipitated on the surface after leaching. The size of the nanoparticles is estimated by high resolution transmission microscopy to be 5-20 nm, which is in agreement with the AFM results. Selected area electron diffraction (SAED) confirms the crystalline nature of the nanoparticles. SAED further reveals the formation of an interface between the high atomic density lattice planes of nanoparticles and the quasicrystal. These results provide an important insight into the preparation of model catalysts of nanoparticles for steam reforming of methanol

  4. Influence of leaching on surface composition, microstructure, and valence band of single grain icosahedral Al-Cu-Fe quasicrystal

    Science.gov (United States)

    Lowe, M.; Yadav, T. P.; Fournée, V.; Ledieu, J.; McGrath, R.; Sharma, H. R.

    2015-03-01

    The use of quasicrystals as precursors to catalysts for the steam reforming of methanol is potentially one of the most important applications of these new materials. To develop application as a technology requires a detailed understanding of the microscopic behavior of the catalyst. Here, we report the effect of leaching treatments on the surface microstructure, chemical composition, and valence band of the icosahedral (i-) Al-Cu-Fe quasicrystal in an attempt to prepare a model catalyst. The high symmetry fivefold surface of a single grain i-Al-Cu-Fe quasicrystal was leached with NaOH solution for varying times, and the resulting surface was characterized by x-ray photoelectron spectroscopy (XPS), ultraviolet photoelectron spectroscopy (UPS), scanning electron microscopy (SEM), and atomic force microscopy (AFM). The leaching treatments preferentially remove Al producing a capping layer consisting of Fe and Cu oxides. The subsurface layer contains elemental Fe and Cu in addition to the oxides. The quasicrystalline bulk structure beneath remains unchanged. The subsurface gradually becomes Fe3O4 rich with increasing leaching time. The surface after leaching exhibits micron sized dodecahedral cavities due to preferential leaching along the fivefold axis. Nanoparticles of the transition metals and their oxides are precipitated on the surface after leaching. The size of the nanoparticles is estimated by high resolution transmission microscopy to be 5-20 nm, which is in agreement with the AFM results. Selected area electron diffraction (SAED) confirms the crystalline nature of the nanoparticles. SAED further reveals the formation of an interface between the high atomic density lattice planes of nanoparticles and the quasicrystal. These results provide an important insight into the preparation of model catalysts of nanoparticles for steam reforming of methanol.

  5. Influence of leaching on surface composition, microstructure, and valence band of single grain icosahedral Al-Cu-Fe quasicrystal

    Energy Technology Data Exchange (ETDEWEB)

    Lowe, M.; McGrath, R.; Sharma, H. R. [Surface Science Research Centre and The Department of Physics, The University of Liverpool, Liverpool L69 3BX (United Kingdom); Yadav, T. P. [Hydrogen Energy Centre, Department of Physics, Banaras Hindu University, Varanasi 221005 (India); Fournée, V.; Ledieu, J. [Institut Jean Lamour (UMR7198 CNRS-Université de Lorraine), Parc de Saurupt, 54011 Nancy Cedex (France)

    2015-03-07

    The use of quasicrystals as precursors to catalysts for the steam reforming of methanol is potentially one of the most important applications of these new materials. To develop application as a technology requires a detailed understanding of the microscopic behavior of the catalyst. Here, we report the effect of leaching treatments on the surface microstructure, chemical composition, and valence band of the icosahedral (i-) Al-Cu-Fe quasicrystal in an attempt to prepare a model catalyst. The high symmetry fivefold surface of a single grain i-Al-Cu-Fe quasicrystal was leached with NaOH solution for varying times, and the resulting surface was characterized by x-ray photoelectron spectroscopy (XPS), ultraviolet photoelectron spectroscopy (UPS), scanning electron microscopy (SEM), and atomic force microscopy (AFM). The leaching treatments preferentially remove Al producing a capping layer consisting of Fe and Cu oxides. The subsurface layer contains elemental Fe and Cu in addition to the oxides. The quasicrystalline bulk structure beneath remains unchanged. The subsurface gradually becomes Fe{sub 3}O{sub 4} rich with increasing leaching time. The surface after leaching exhibits micron sized dodecahedral cavities due to preferential leaching along the fivefold axis. Nanoparticles of the transition metals and their oxides are precipitated on the surface after leaching. The size of the nanoparticles is estimated by high resolution transmission microscopy to be 5-20 nm, which is in agreement with the AFM results. Selected area electron diffraction (SAED) confirms the crystalline nature of the nanoparticles. SAED further reveals the formation of an interface between the high atomic density lattice planes of nanoparticles and the quasicrystal. These results provide an important insight into the preparation of model catalysts of nanoparticles for steam reforming of methanol.

  6. Near-Band-Edge Optical Responses of CH3NH3PbCl3 Single Crystals: Photon Recycling of Excitonic Luminescence

    Science.gov (United States)

    Yamada, Takumi; Aharen, Tomoko; Kanemitsu, Yoshihiko

    2018-02-01

    The determination of the band gap and exciton energies of lead halide perovskites is very important from the viewpoint of fundamental physics and photonic device applications. By using photoluminescence excitation (PLE) spectra, we reveal the optical properties of CH3NH3PbCl3 single crystals in the near-band-edge energy regime. The one-photon PLE spectrum exhibits the 1 s exciton peak at 3.11 eV. On the contrary, the two-photon PLE spectrum exhibits no peak structure. This indicates photon recycling of excitonic luminescence. By analyzing the spatial distribution of the excitons and photon recycling, we obtain 3.15 eV for the band gap energy and 41 meV for the exciton binding energy.

  7. The prospective association between obesity and major depression in the general population : does single or recurrent episode matter?

    NARCIS (Netherlands)

    Nigatu, Yeshambel T.; Bultmann, Ute; Reijneveld, Sijmen A.

    2015-01-01

    Background: Obesity and major depressive disorder (MDD) are important public health problems. MDD is a heterogeneous disorder and the direction of its association with obesity remains unclear. Evidence grows that recurrent MDD (MDD-R) differs in etiology and prognosis from single episode MDD

  8. Reconstrução anatômica do ligamento cruzado anterior do joelho: banda dupla ou banda simples? Anatomical reconstruction of anterior cruciate ligament of the knee: double band or single band?

    Directory of Open Access Journals (Sweden)

    Luiz Antonio Zanotelli Zanella

    2012-04-01

    Full Text Available OBJETIVO: Avaliar as técnicas de banda dupla e banda simples para reconstrução anatômica do ligamento cruzado anterior do joelho e comprovar que a técnica de dupla banda, além de fornecer maior estabilidade anterior, também causa menor dor e uma melhor resposta subjetiva do paciente. MÉTODOS: Selecionamos 42 pacientes que foram submetidos à reconstrução do LCA, conforme a técnica de reconstrução anatômica por banda simples com enxerto de tendões flexores com dois túneis ou reconstrução anatômica por banda dupla e quatro túneis com enxerto de tendões dos músculos semitendíneo e gracilis. Todas as fixações foram realizadas com parafusos de interferência. Não houve variação na amostra, avaliou-se no pré-operatório IKDC objetivo, subjetivo, Lysholm e tempo de lesão. Reavaliou-se após seis meses todas as variáveis anteriormente citadas, incluindo o KT-1000 correlacionando o joelho contralateral. RESULTADOS: Não houve diferença significativa entre os dois grupos nas avaliações subjetivas, mas na amplitude de movimento, nas avaliações objetivas, incluindo o KT-1000 (com significância estatística, o grupo da banda simples anatômica obteve melhores resultados. CONCLUSÃO: Nosso estudo demonstra que não obtivemos diferença entre os dois grupos nas avaliações subjetivas, porém nas avaliações objetivas observamos melhores resultados na técnica por banda simples anatômica.OBJECTIVE: To evaluate the double-band and single-band techniques for anatomical reconstruction of the anterior cruciate ligament of the knee and demonstrate that the double-band technique not only provides greater anterior stability but also causes less pain and a better subjective patient response. METHODS: We selected 42 patients who underwent anterior cruciate ligament reconstruction, by means of either the single-band anatomical reconstruction technique, using flexor tendon grafts with two tunnels, or the double-band anatomical

  9. Strong visible and near infrared photoluminescence from ZnO nanorods/nanowires grown on single layer graphene studied using sub-band gap excitation

    Science.gov (United States)

    Biroju, Ravi K.; Giri, P. K.

    2017-07-01

    Fabrication and optoelectronic applications of graphene based hybrid 2D-1D semiconductor nanostructures have gained tremendous research interest in recent times. Herein, we present a systematic study on the origin and evolution of strong broad band visible and near infrared (NIR) photoluminescence (PL) from vertical ZnO nanorods (NRs) and nanowires (NWs) grown on single layer graphene using both above band gap and sub-band gap optical excitations. High resolution field emission scanning electron microscopy and X-ray diffraction studies are carried out to reveal the morphology and crystalline quality of as-grown and annealed ZnO NRs/NWs on graphene. Room temperature PL studies reveal that besides the UV and visible PL bands, a new near-infrared (NIR) PL emission band appears in the range between 815 nm and 886 nm (1.40-1.52 eV). X-ray photoelectron spectroscopy studies revealed excess oxygen content and unreacted metallic Zn in the as-grown ZnO nanostructures, owing to the low temperature growth by a physical vapor deposition method. Post-growth annealing at 700 °C in the Ar gas ambient results in the enhanced intensity of both visible and NIR PL bands. On the other hand, subsequent high vacuum annealing at 700 °C results in a drastic reduction in the visible PL band and complete suppression of the NIR PL band. PL decay dynamics of green emission in Ar annealed samples show tri-exponential decay on the nanosecond timescale including a very slow decay component (time constant ˜604.5 ns). Based on these results, the NIR PL band comprising two peaks centered at ˜820 nm and ˜860 nm is tentatively assigned to neutral and negatively charged oxygen interstitial (Oi) defects in ZnO, detected experimentally for the first time. The evidence for oxygen induced trap states on the ZnO NW surface is further substantiated by the slow photocurrent response of graphene-ZnO NRs/NWs. These results are important for tunable light emission, photodetection, and other cutting edge

  10. Estimating the Genetic Variance of Major Depressive Disorder Due to All Single Nucleotide Polymorphisms

    NARCIS (Netherlands)

    Lubke, Gitta H.; Hottenga, Jouke Jan; Walters, Raymond; Laurin, Charles; de Geus, Eco J. C.; Willemsen, Gonneke; Smit, Jan H.; Middeldorp, Christel M.; Penninx, Brenda W. J. H.; Vink, Jacqueline M.; Boomsma, Dorret I.

    2012-01-01

    Genome-wide association studies of psychiatric disorders have been criticized for their lack of explaining a considerable proportion of the heritability established in twin and family studies. Genome-wide association studies of major depressive disorder in particular have so far been unsuccessful in

  11. Single Layer Molybdenum Disulfide under Direct Out-of-Plane Compression: Low-Stress Band-Gap Engineering

    Czech Academy of Sciences Publication Activity Database

    Álvarez, M. P.; del Corro, Elena; Morales-García, A.; Kavan, Ladislav; Kalbáč, Martin; Frank, Otakar

    2015-01-01

    Roč. 15, č. 5 (2015), s. 3139-3146 ISSN 1530-6984 R&D Projects: GA ČR GA14-15357S; GA MŠk LL1301 Institutional support: RVO:61388955 Keywords : Molybdenum disulfide * band gap engineering * out-of-plane compression Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 13.779, year: 2015

  12. XRF determination of trace and major elements using a single-fused disc

    International Nuclear Information System (INIS)

    Thomas, I.R.; Haukka, M.T.

    1978-01-01

    A new fusion method using lithium metaborate, suitable for the determination of major and trace elements by X-ray fluorescence analysis (XRF), has proven to be of comparable accuracy to other XRF methods for the ten major rock-forming oxides. The very low dilution allows determination of trace elements with a decrease in sensitivity of about a factor of 2 compared with XRF determination using pressed-powder pellets. A feature of the method is the flexibility of sample preparation allowed: the matrix-correction parameters may be used for a wide range of dilutions (sample/flux ratios), no 'Loss' correction is necessary, and imperfect or inhomogeneous discs may be crushed and pressed pellets made of the glass powder when required. Considerable savings in the time during preparation, analysis and correction of results are possible with current automation because of streamlining procedures

  13. Photodoping and enhanced visible light absorption in single-walled carbon nanotubes functionalized with a wide band gap oligomer.

    Science.gov (United States)

    Bunes, Benjamin R; Xu, Miao; Zhang, Yaqiong; Gross, Dustin E; Saha, Avishek; Jacobs, Daniel L; Yang, Xiaomei; Moore, Jeffrey S; Zang, Ling

    2015-01-07

    Carbon nanotubes feature excellent electronic properties but narrow absorption bands limit their utility in certain optoelectronic devices, including photovoltaic cells. Here, the addition of a wide-bandgap gap oligomer enhances light absorption in the visible spectrum. Furthermore, the oligomer interacts with the carbon nanotube through a peculiar charge transfer, which provides insight into Type II heterojunctions. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Evaluating the Solar Slowly Varying Component at C-Band Using Dual- and Single-Polarization Weather Radars in Europe

    Directory of Open Access Journals (Sweden)

    M. Gabella

    2017-01-01

    Full Text Available Six C-band weather radars located in Europe (Finland, Netherlands, and Switzerland have been used to monitor the slowly varying solar emission, which is an oscillation with an amplitude of several decibels and a period of approximately 27 days. It is caused by the fact that the number of active regions that enhance the solar radio emission with respect to the quiet component, as seen from Earth, varies because of the Sun’s rotation about its axis. The analysis is based on solar signals contained in the polar volume data produced during the operational weather scan strategy. This paper presents hundreds of daily comparisons between radar estimates and the Sun’s reference signal, during the current active Sun period (year 2014. The Sun’s reference values are accurately measured by the Dominion Radio Astrophysical Observatory (DRAO at S-band and converted to C-band using a standard DRAO formula. Vertical and horizontal polarization receivers are able to capture the monthly oscillation of the solar microwave signal: the standard deviation of the log-transformed ratio between radars and the DRAO reference ranges from 0.26 to 0.4 dB. A larger coefficient (and a different value for the quiet Sun component in the standard formula improves the agreement.

  15. Endocrinopathies in Turkish children with Beta thalassemia major: results from a single center study.

    Science.gov (United States)

    Isik, Pamir; Yarali, Nese; Tavil, Betül; Demirel, Fatma; Karacam, Gülşah Bayram; Sac, Rukiye Unsal; Fettah, Ali; Ozkasap, Serdar; Kara, Abdurrahman; Tunc, Bahattin

    2014-10-01

    The endocrinological complications in β-thalassemia major patients do affect the life quality to a large extend. In this study, the endocrinological complications of 47 β-thalassemia patients, who have been followed-up at our hospital's pediatric hematology department, were evaluated. Out of β-thalassemia major cases included to this study, the 55.3% was male and 44.7% was female. The patients' mean levels of ferritin, whose mean age was 10.0 ± 4.5 years (2-20 years), were 2497 ± 1469 ng/mL (472-8558 ng/mL). At least one endocrinological pathology in 27 out of 47 (57.4%) and more than one endocrinological pathology in 14 out of 47 (29.7%) thalassemia patients were observed. The most frequently observed complication in followed-up cases was vitamin D insufficiency and deficiency (78.2%). The other complications in decreasing order were pubertal failure (41.6%), growth retardation (25.5%), decreased bone-mineral density (22.2%), secondary hyperparathyroidism (11.5%), overt hypothyroidism (4.25%), subclinical hypothyroidism (2.12%), and impaired glucose tolerance (2.12%). There was no statistically significant difference between serum mean ferritin level and endocrin complications (P > .05). Four patients (8.5%) had decreased signal intensity in pituitary magnetic resonance imaging (MRI) but this finding was not associated with ferritin levels (P = .87). MRI parameters were similar between patients with and without gonadal dysfunction. Mean height of the pituitary gland was 4.98 ± 1.1 mm (3-9 mm) and this was similar to those normal values in the literature. Ferritin levels were not correlated with pituitary height (P > .05). Beta thalassemia major, having the potential of leading to multisystemic complications, is a chronic disease that should be treated and followed-up by a multidisciplinary approach. Due to frequently encountered endocrinological complications, beta thalassemic patients should be followed-up regularly by hematology and endocrinology

  16. Crystal orientation dependent optical transmittance and band gap of Na0.5Bi0.5TiO3-BaTiO3 single crystals

    Science.gov (United States)

    He, Chongjun; Deng, Chenguang; Wang, Jiming; Gu, Xiaorong; Wu, Tong; Zhu, Kongjun; Liu, Youwen

    2016-02-01

    Optical transmittance spectra of lead-free ferroelectric (1-x)Na0.5Bi0.5TiO3-xBaTiO3 (NBT-xBT) single crystals poled along different directions have been studied comprehensively. After poled along [001] direction, the transmittance of tetragonal NBT-8%BT crystal is about 70%, which is much higher than that of NBT-2%BT crystal with rhombohedral structure and NBT-5%BT crystal with morphotropic phase boundary (MPB) composition. However, after poled [111] direction, the transmittance of tetragonal NBT-8%BT crystal is the smallest among them. These properties are manifest in view of the crystal structure. Both direct and indirect optical energy band gaps, as well phonon energies were obtained from absorption coefficient spectra by Tauc equations. The band gaps of [001]-poled NBT-xBT crystals increase with BT content, yet the [111]-poled crystals have opposite trends.

  17. 100-Gb/s 80-km transmission of PIM-SSB-OFDM at C-band using a single-end photodetector

    Science.gov (United States)

    Huo, Jiahao; Zhou, Xian; Zhong, Kangping; Gui, Tao; Tan, Fengze; Tu, Jiajing; Yuan, Jinhui; Zhang, Hongyu; Long, Keping; Yu, Changyuan; Lau, Alan Pak Tao; Lu, Chao

    2017-10-01

    Polarization-interleave-multiplexed (PIM) with single-sideband orthogonal frequency-division multiplexing (SSB-OFDM) based on direct detection is proposed for short-reach applications transmitted up to 80 km in which the guard band can be shared for the two SSB signals with interleave electrical center frequencies. Based on two dual-drive Mach-Zehnder modulators with one single-end photodetector (PD), 100-Gb/s PIM-SSB-OFDM transmission over a 80-km standard single-mode fiber is successfully demonstrated. After 80-km transmission, the optical signal-to-noise ratio requirement is 29.1 dB with respect to the bit error rate threshold of 7% hard decision-forward error correction overhead.

  18. Single- and Multiband OFDM Photonic Wireless Links in the 75−110 GHz Band Employing Optical Combs

    DEFF Research Database (Denmark)

    Beltrán, M.; Deng, Lei; Pang, Xiaodan

    2012-01-01

    The photonic generation of electrical orthogonal frequency-division multiplexing (OFDM) modulated wireless signals in the 75−110 GHz band is experimentally demonstrated employing in-phase/quadrature electrooptical modulation and optical heterodyn upconversion. The wireless transmission of 16......-quadrature-amplitude-modulation OFDM signals is demonstrated with a bit error rate performance within the forward error correction limits. Signals of 19.1 Gb/s in 6.3-GHz bandwidth are transmitted over up to 1.3-m wireless distance. Optical comb generation is further employed to support different channels...

  19. Crop Classification by Multitemporal C- and L-Band Single- and Dual-Polarization and Fully Polarimetric SAR

    DEFF Research Database (Denmark)

    Skriver, Henning

    2012-01-01

    Classification of crops and other land cover types is an important application of both optical/infrared and synthetic aperture radar (SAR) satellite data. It is already an import application of present satellite systems, as it will be for planned missions, such as the Sentinels. A multitemporal...... data set from the Danish airborne polarimetric EMISAR has been used to assess the performance of different polarization modes for crop classification. Both C- and L-band SAR data were acquired simultaneously over the Foulum agricultural test site in Denmark on a monthly basis during the growing season...

  20. Medium- to Long-Term Outcomes of Gastric Banding in Adolescents: a Single-Center Study of 97 Consecutive Patients.

    Science.gov (United States)

    Dumont, Paul-Noël; Blanchet, Marie-Cécile; Gignoux, Benoît; Matussière, Yann; Frering, Vincent

    2018-01-01

    Morbid obesity in adolescents has been treated effectively with laparoscopic adjustable gastric banding (LAGB). We prospectively studied 97 consecutive obese adolescents undergoing LAGB over the course of 10 years. The average patient age at surgery was 17.2 ± 0.7 years; mean body mass index, 44.9 ± 6.1 kg/m 2 . Excluding those lost to follow-up (n = 21), respective mean total weight loss and excess weight loss were 20.0 ± 16.6 and 46.6 ± 39.5% (n = 76, 78.4%). An ascending trend line showed a significant positive correlation between excess weight loss and follow-up duration (mean 56.0 ± 22.0 months). There was no mortality or morbidity. Nineteen patients (25.0%) underwent band removal at a mean 43.0 ± 28.0 months. LAGB proved safe and effective over the mid- and longer term; it should be strongly considered as a procedure of first intention for obese adolescents.

  1. The Prevalence and Distribution of Spina Bifida in a Single Major Referral Center in Malaysia

    Directory of Open Access Journals (Sweden)

    Adibah Sahmat

    2017-11-01

    UMMC is as according to international statistics which is in the range of 0.5–10 per 1,000 live births. Majority of the reported cases were males, Malays, full term babies, and of the myelomeningocele phenotype located at the lumbar region.

  2. The Prevalence and Distribution of Spina Bifida in a Single Major Referral Center in Malaysia.

    Science.gov (United States)

    Sahmat, Adibah; Gunasekaran, Renuka; Mohd-Zin, Siti W; Balachandran, Lohis; Thong, Meow-Keong; Engkasan, Julia P; Ganesan, Dharmendra; Omar, Zaliha; Azizi, Abu Bakar; Ahmad-Annuar, Azlina; Abdul-Aziz, Noraishah M

    2017-01-01

    international statistics which is in the range of 0.5-10 per 1,000 live births. Majority of the reported cases were males, Malays, full term babies, and of the myelomeningocele phenotype located at the lumbar region.

  3. High Power Test of X-band Single Cell HOM-free Choke-mode Damped Accelerating Structure made by Tsinghua University

    OpenAIRE

    Wu, Xiaowei; Abe, Tetsuo; Chen, Huaibi; Higo, Toshiyasu; Shi, Jiaru; Wuensch, Walter; Zha, Hao

    2016-01-01

    As an alternative design for CLIC main accelerating structures, X-band choke-mode damped structures had been studied for several years. However, the performance of choke-mode cavity under high power is still in lack of research. Two standing wave single cell choke-mode damped accelerating structures with different choke dimensions which are working at 11.424 GHz were designed, manufactured and bench tested by accelerator group in Tsinghua University. High power test was carried out on it to s...

  4. g-Anisotropy of the S2-state manganese cluster in single crystals of cyanobacterial photosystem II studied by W-band electron paramagnetic resonance spectroscopy.

    Science.gov (United States)

    Matsuoka, Hideto; Furukawa, Ko; Kato, Tatsuhisa; Mino, Hiroyuki; Shen, Jian-Ren; Kawamori, Asako

    2006-07-06

    The multiline signal from the S2-state manganese cluster in the oxygen evolving complex of photosystem II (PSII) was observed in single crystals of a thermophilic cyanobacterium Thermosynechococcus vulcanus for the first time by W-band (94 GHz) electron paramagnetic resonance (EPR). At W-band, spectra were characterized by the g-anisotropy, which enabled the precise determination of the tensor. Distinct hyperfine splittings (hfs's) as seen in frozen solutions of PSII at X-band (9.5 GHz) were detected in most of the crystal orientations relative to the magnetic field. In some orientations, however, the hfs's disappeared due to overlapping of a large number of EPR lines from eight crystallographic symmetry-related sites of the manganese cluster within the unit cell of the crystal. Analysis of the orientation-dependent spectral features yielded the following g-tensor components: g(x) = 1.988, g(y) = 1.981, g(z) = 1.965. The principal values suggested an approximate axial symmetry around the Mn(III) ion in the cluster.

  5. Expanded graphite/Novolac phenolic resin composite as single layer electromagnetic wave absorber for x-band applications

    Science.gov (United States)

    Gogoi, Jyoti P.; Bhattacharyya, Nidhi Saxena

    2013-01-01

    Expanded graphite/novolac phenolic resin (EG/NPR) composites are developed as dielectric absorbers with 4mm thickness and its microwave absorption ability studied in the frequency range 8.4 to 12.4 GHz. A high reflection loss ~ -43 dB is observed at 12.4 GHz for 5 wt. % EG/NPR composites. With the increase in EG concentration in the composite the reflection loss decreases and the absorption peak shifts towards lower frequency. 7 wt. %, 8 wt. % and 10 wt. % composites shows a 10dB absorption bandwidth of order of 1GHz. Light weight EG/NPR composite shows potential to be used as cost-effective broadband microwave absorber over the X-band.

  6. InGaAsP/InP Nanocavity for Single-Photon Source at 1.55-μm Telecommunication Band.

    Science.gov (United States)

    Song, Hai-Zhi; Hadi, Mukhtar; Zheng, Yanzhen; Shen, Bizhou; Zhang, Lei; Ren, Zhilei; Gao, Ruoyao; Wang, Zhiming M

    2017-12-01

    A new structure of 1.55-μm pillar cavity is proposed. Consisting of InP-air-aperture and InGaAsP layers, this cavity can be fabricated by using a monolithic process, which was difficult for previous 1.55-μm pillar cavities. Owing to the air apertures and tapered distributed Bragg reflectors, such a pillar cavity with nanometer-scaled diameters can give a quality factor of 10 4 -10 5 at 1.55 μm. Capable of weakly and strongly coupling a single quantum dot with an optical mode, this nanocavity could be a prospective candidate for quantum-dot single-photon sources at 1.55-μm telecommunication band.

  7. Fermi energy dependence of the G-band resonance Raman spectra of single-wall carbon nanotubes

    Czech Academy of Sciences Publication Activity Database

    Park, J. S.; Sasaki, K.; Saito, R.; Izumida, W.; Kalbáč, Martin; Farhat, H.; Dresselhaus, G.; Dresselhaus, M. S.

    2009-01-01

    Roč. 80, č. 8 (2009), 081402-1-081402-4 ISSN 1098-0121 R&D Projects: GA MŠk LC510; GA MŠk ME09060 Institutional research plan: CEZ:AV0Z40400503 Keywords : Fermi energy dependence * Raman spectroscopy * single waled carbon nanotubes Subject RIV: CG - Electrochemistry Impact factor: 3.475, year: 2009

  8. Compact source of narrow-band counterpropagating polarization-entangled photon pairs using a single dual-periodically-poled crystal

    International Nuclear Information System (INIS)

    Gong, Yan-Xiao; Xie, Zhen-Da; Xu, Ping; Zhu, Shi-Ning; Yu, Xiao-Qiang; Xue, Peng

    2011-01-01

    We propose a scheme for the generation of counterpropagating polarization-entangled photon pairs from a dual-periodically-poled crystal. Compared with the usual forward-wave-type source, this source, in the backward-wave way, has a much narrower bandwidth. With a 2-cm-long bulk crystal, the bandwidths of the example sources are estimated to be 3.6 GHz, and the spectral brightnesses are more than 100 pairs/(s GHz mW). Two concurrent quasi-phase-matched spontaneous parametric down-conversion processes in a single crystal enable our source to be compact and stable. This scheme does not rely on any state projection and applies to both degenerate and nondegenerate cases, facilitating applications of the entangled photons.

  9. Band-head spectra of low-energy single-particle excitations in some well-deformed, odd-mass heavy nuclei within a microscopic approach

    Energy Technology Data Exchange (ETDEWEB)

    Koh, Meng-Hock [Universiti Teknologi Malaysia, Skudai, Johor (Malaysia); Univ. Bordeaux, CENBG, UMR5797, Gradignan (France); CNRS, IN2P3, CENBG, UMR5797, Gradignan (France); Duc, Dao Duy [Ton Duc Thang University, Division of Nuclear Physics, Ho Chi Minh City (Viet Nam); Ton Duc Thang University, Faculty of Applied Sciences, Ho Chi Minh City (Viet Nam); Nhan Hao, T.V. [Duy Tan University, Center of Research and Development, Danang (Viet Nam); Hue University, Center for Theoretical and Computational Physics, College of Education, Hue City (Viet Nam); Long, Ha Thuy [Hanoi University of Sciences, Vietnam National University, Hanoi (Viet Nam); Quentin, P. [Universiti Teknologi Malaysia, Skudai, Johor (Malaysia); Univ. Bordeaux, CENBG, UMR5797, Gradignan (France); CNRS, IN2P3, CENBG, UMR5797, Gradignan (France); Ton Duc Thang University, Division of Nuclear Physics, Ho Chi Minh City (Viet Nam); Bonneau, L. [Univ. Bordeaux, CENBG, UMR5797, Gradignan (France); CNRS, IN2P3, CENBG, UMR5797, Gradignan (France)

    2016-01-15

    In four well-deformed heavy odd nuclei, the energies of low-lying rotational band heads have been determined microscopically within a self-consistent Hartree-Fock-plus-BCS approach with blocking. A Skyrme nucleon-nucleon effective interaction has been used together with a seniority force to describe pairing correlations. Only such states which are phenomenologically deemed to be related to single-particle excitations have been considered. The polarization effects, including those associated with the genuine time-reversal symmetry breaking have been fully taken into account within our model assumptions. The calculated spectra are in reasonably good qualitative agreement with available data for the considered odd-neutron nuclei. This is not so much the case for the odd-proton nuclei. A potential explanation for such a difference in behavior is proposed. (orig.)

  10. Personality in remitted major depressive disorder with single and recurrent episodes assessed with the Temperament and Character Inventory.

    Science.gov (United States)

    Teraishi, Toshiya; Hori, Hiroaki; Sasayama, Daimei; Matsuo, Junko; Ogawa, Shintaro; Ishida, Ikki; Nagashima, Anna; Kinoshita, Yukiko; Ota, Miho; Hattori, Kotaro; Higuchi, Teruhiko; Kunugi, Hiroshi

    2015-01-01

    Previous studies consistently reported increased harm avoidance (HA) assessed with the Temperament and Character Inventory (TCI) in patients with major depressive disorder (MDD). However, such findings may have been related with depression severity and number of depressive episodes. The aims of the present study were twofold: to examine TCI personality profile in remitted MDD (DSM-IV) patients and to compare TCI personality between MDD patients with single episode (SGL-MDD) and those with recurrent episodes (REC-MDD) in order to elucidate personality profile associated with recurrence. TCI was administered to 86 outpatients with remitted SGL-MDD (12 male and 17 female patients; mean age 43.2 ± 12.1 years) and REC-MDD (26 male and 31 female patients; 40.3 ± 11.6 years), and 529 healthy controls (225 men and 304 women; 43.4 ± 15.5 years), matched for age, sex and education years. Logistic regression analyses were performed in which single/recurrent episodes of depression were the dependent variable and age, sex, age of onset, family history of psychiatric disease and TCI scores were entered as possible predictors. The remitted MDD patients had significantly higher scores on HA (P personality profile between remitted MDD patients and controls, and between remitted REC-MDD and SGL-MDD patients, suggesting that they are trait markers. HA and fatigability might be useful to assess risk for recurrence of depression. © 2014 The Authors. Psychiatry and Clinical Neurosciences © 2014 Japanese Society of Psychiatry and Neurology.

  11. Multi-institutional Experience in Laparoendoscopic Single-site Surgery (LESS): For Major Extirpative and Reconstructive Procedures in Pediatric Urology.

    Science.gov (United States)

    Gor, Ronak A; Long, Christopher J; Shukla, Aseem R; Kirsch, Andrew J; Perez-Brayfield, Marcos; Srinivasan, Arun K

    2016-02-01

    To review peri-procedural outcomes from a large, multi-institutional series of pediatric urology patients treated with laparaendoscopic single-site surgery (LESS) for major extirpative and reconstructive procedures. Consecutive LESS cases between January 2011 and May 2014 from three free-standing pediatric referral centers were reviewed. Data include age, sex, operative time, blood loss, length of stay, and complications according to the modified Clavien-Dindo classification. Hasson technique was used for peritoneal entry, GelPOINT advanced access platform was inserted, and standard 5mm laparoscopic instruments were used. Fifty-nine patients (median age 5 years, 4 months-17 years) met inclusion criteria: 29 nephrectomies, 9 nephroureterectomies, 3 bilateral nephrectomies, 5 heminephrectomies, 5 renal cyst decortications, 3 bilateral gonadectomies, 2 Malone antegrade continence enema, 2 calyceal diverticulectomy, and 1 ovarian detorsion with cystectomy. Median operative times for each case type were comparable to published experiences with traditional laparoscopy. Overall mean and median length of stay was 36.2 hours and 1 day, respectively. There were two complications: port site hernia requiring surgical repair (Clavien IIIb) and a superficial port site infection that resolved with antibiotics (Clavien II). Cosmetic outcomes were subjectively well received by patients and their parents. Operative time was significantly shorter between the first half of the experience and the second half (102 vs 70 minutes, P  <  .05). LESS approach can be broadly applied across many major extirpative and reconstructive procedures within pediatric urology. Our series advances our field's utilization of this technique and its safety. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Laboratory estimate of the regional shortwave refractive index and single scattering albedo of mineral dust from major sources worldwide

    Science.gov (United States)

    Di Biagio, C.; Formenti, P.; Caponi, L.; Cazaunau, M.; Pangui, E.; Journet, E.; Nowak, S.; Caquineau, S.; Andreae, M. O.; Kandler, K.; Saeed, T.; Piketh, S.; Seibert, D.; Williams, E.; Balkanski, Y.; Doussin, J. F.

    2017-12-01

    Mineral dust is one of the most abundant aerosol species in the atmosphere and strongly contributes to the global and regional direct radiative effect. Still large uncertainties persist on the magnitude and overall sign of the dust direct effect, where indeed one of the main unknowns is how much mineral dust absorbs light in the shortwave (SW) spectral range. Aerosol absorption is represented both by the imaginary part (k) of the complex refractive index or the single scattering albedo (SSA, i.e. the ratio of the scattering to extinction coefficient). In this study we present a new dataset of SW complex refractive indices and SSA for mineral dust aerosols obtained from in situ measurements in the 4.2 m3 CESAM simulation chamber at LISA (Laboratoire Interuniversitaire des Systemes Atmospheriques) in Créteil, France. Investigated dust aerosol samples were issued from major desert sources worldwide, including the African Sahara and Sahel, Eastern Asia, the Middle East, Southern Africa, Australia, and the Americas, with differing iron oxides content. Results from the present study provide a regional mapping of the SW absorption by dust and show that the imaginary part of the refractive index largely varies (by up to a factor 6, 0.003-0.02 at 370 nm and 0.001-0.003 at 950 nm) for the different source areas due to the change in the particle iron oxide content. The SSA for dust varies between 0.75-0.90 at 370 nm and 0.95-0.99 at 950 nm, with the largest absorption observed for Sahelian and Australian dust aerosols. Our range of variability for k and SSA is well bracketed by already published literature estimates, but suggests that regional‒dependent values should be used in models. The possible relationship between k and the dust iron oxides content is investigated with the aim of providing a parameterization of the regional‒dependent dust absorption to include in climate models.

  13. Magnetic properties of weakly exchange-coupled high spin Co(II) ions in pseudooctahedral coordination evaluated by single crystal X-band EPR spectroscopy and magnetic measurements.

    Science.gov (United States)

    Neuman, Nicolás I; Winkler, Elín; Peña, Octavio; Passeggi, Mario C G; Rizzi, Alberto C; Brondino, Carlos D

    2014-03-03

    We report single-crystal X-band EPR and magnetic measurements of the coordination polymer catena-(trans-(μ2-fumarato)tetraaquacobalt(II)), 1, and the Co(II)-doped Zn(II) analogue, 2, in different Zn:Co ratios. 1 presents two magnetically inequivalent high spin S = 3/2 Co(II) ions per unit cell, named A and B, in a distorted octahedral environment coordinated to four water oxygen atoms and trans coordinated to two carboxylic oxygen atoms from the fumarate anions, in which the Co(II) ions are linked by hydrogen bonds and fumarate molecules. Magnetic susceptibility and magnetization measurements of 1 indicate weak antiferromagnetic exchange interactions between the S = 3/2 spins of the Co(II) ions in the crystal lattice. Oriented single crystal EPR experiments of 1 and 2 were used to evaluate the molecular g-tensor and the different exchange coupling constants between the Co(II) ions, assuming an effective spin S′= 1/2. Unexpectedly, the eigenvectors of the molecular g-tensor were not lying along any preferential bond direction, indicating that, in high spin Co(II) ions in roughly octahedral geometry with approximately axial EPR signals, the presence of molecular pseudo axes in the metal site does not determine preferential directions for the molecular g-tensor. The EPR experiment and magnetic measurements, together with a theoretical analysis relating the coupling constants obtained from both techniques, allowed us to evaluate selectively the exchange coupling constant associated with hydrogen bonds that connect magnetically inequivalent Co(II) ions (|JAB(1/2)| = 0.055(2) cm(–1)) and the exchange coupling constant associated with a fumarate bridge connecting equivalent Co(II) ions (|JAA(1/2)| ≈ 0.25 (1) cm(–1)), in good agreement with the average J(3/2) value determined from magnetic measurements.

  14. 25–34 GHz Single-Pole, Double-Throw CMOS Switches for a Ka-Band Phased-Array Transceiver

    Directory of Open Access Journals (Sweden)

    Sangyong Park

    2018-01-01

    Full Text Available This paper presents two single-pole, double-throw (SPDT mm-wave switches for Ka-band phased-array transceivers, fabricated with a 65-nm complementary metal oxide semiconductor (CMOS process. One switch employs cross-biasing (CB control with a single supply, while the other uses dual-supply biasing (DSB control with positive and negative voltages. Negative voltages were generated internally, using a ring oscillator and a charge pump. Identical gate and body floated N-type metal oxide semiconductor field effect transistors (N-MOSFETs in a triple well were used as the switch core transistors. Inductors were used to improve the isolation between the transmitter (TX and receiver (RX, as well as insertion loss, by canceling the parasitic capacitance of the switch core transistors at resonance. The size of the proposed radio frequency (RF switch is 260 μm × 230 μm, excluding all pads. The minimum insertion losses of the CB and DSB switches were 2.1 dB at 28 GHz and 1.93 dB at 24 GHz, respectively. Between 25 GHz and 34 GHz, the insertion losses were less than 2.3 dB and 2.5 dB, the return losses were less than 16.7 dB and 17.3 dB, and the isolation was over 18.4 dB and 15.3 dB, respectively. The third order input intercept points (IIP3 of the CB and DSB switches were 38.4 dBm and 39 dBm at 28 GHz, respectively.

  15. A Cross-Reactive Human Single-Chain Antibody for Detection of Major Fish Allergens, Parvalbumins, and Identification of a Major IgE-Binding Epitope.

    Directory of Open Access Journals (Sweden)

    Merima Bublin

    Full Text Available Fish allergy is associated with moderate to severe IgE-mediated reactions to the calcium binding parvalbumins present in fish muscle. Allergy to multiple fish species is caused by parvalbumin-specific cross-reactive IgE recognizing conserved epitopes. In this study, we aimed to produce cross-reactive single chain variable fragment (scFv antibodies for the detection of parvalbumins in fish extracts and the identification of IgE epitopes. Parvalbumin-specific phage clones were isolated from the human ETH-2 phage display library by three rounds of biopanning either against cod parvalbumin or by sequential biopanning against cod (Gad m 1, carp (Cyp c 1 and rainbow trout (Onc m 1 parvalbumins. While biopanning against Gad m 1 resulted in the selection of clones specific exclusively for Gad m 1, the second approach resulted in the selection of clones cross-reacting with all three parvalbumins. Two clones, scFv-gco9 recognizing all three parvalbumins, and scFv-goo8 recognizing only Gad m 1 were expressed in the E. coli non-suppressor strain HB2151 and purified from the periplasm. scFv-gco9 showed highly selective binding to parvalbumins in processed fish products such as breaded cod sticks, fried carp and smoked trout in Western blots. In addition, the scFv-gco9-AP produced as alkaline phosphatase fusion protein, allowed a single-step detection of the parvalbumins. In competitive ELISA, scFv-gco9 was able to inhibit binding of IgE from fish allergic patients' sera to all three β-parvalbumins by up to 80%, whereas inhibition by scFv-goo8 was up to 20%. 1H/15N HSQC NMR analysis of the rGad m 1:scFv-gco9 complex showed participation of amino acid residues conserved among these three parvalbumins explaining their cross-reactivity on a molecular level. In this study, we have demonstrated an approach for the selection of cross-reactive parvalbumin-specific antibodies that can be used for allergen detection and for mapping of conserved epitopes.

  16. A Cross-Reactive Human Single-Chain Antibody for Detection of Major Fish Allergens, Parvalbumins, and Identification of a Major IgE-Binding Epitope.

    Science.gov (United States)

    Bublin, Merima; Kostadinova, Maria; Fuchs, Julian E; Ackerbauer, Daniela; Moraes, Adolfo H; Almeida, Fabio C L; Lengger, Nina; Hafner, Christine; Ebner, Christof; Radauer, Christian; Liedl, Klaus R; Valente, Ana Paula; Breiteneder, Heimo

    2015-01-01

    Fish allergy is associated with moderate to severe IgE-mediated reactions to the calcium binding parvalbumins present in fish muscle. Allergy to multiple fish species is caused by parvalbumin-specific cross-reactive IgE recognizing conserved epitopes. In this study, we aimed to produce cross-reactive single chain variable fragment (scFv) antibodies for the detection of parvalbumins in fish extracts and the identification of IgE epitopes. Parvalbumin-specific phage clones were isolated from the human ETH-2 phage display library by three rounds of biopanning either against cod parvalbumin or by sequential biopanning against cod (Gad m 1), carp (Cyp c 1) and rainbow trout (Onc m 1) parvalbumins. While biopanning against Gad m 1 resulted in the selection of clones specific exclusively for Gad m 1, the second approach resulted in the selection of clones cross-reacting with all three parvalbumins. Two clones, scFv-gco9 recognizing all three parvalbumins, and scFv-goo8 recognizing only Gad m 1 were expressed in the E. coli non-suppressor strain HB2151 and purified from the periplasm. scFv-gco9 showed highly selective binding to parvalbumins in processed fish products such as breaded cod sticks, fried carp and smoked trout in Western blots. In addition, the scFv-gco9-AP produced as alkaline phosphatase fusion protein, allowed a single-step detection of the parvalbumins. In competitive ELISA, scFv-gco9 was able to inhibit binding of IgE from fish allergic patients' sera to all three β-parvalbumins by up to 80%, whereas inhibition by scFv-goo8 was up to 20%. 1H/15N HSQC NMR analysis of the rGad m 1:scFv-gco9 complex showed participation of amino acid residues conserved among these three parvalbumins explaining their cross-reactivity on a molecular level. In this study, we have demonstrated an approach for the selection of cross-reactive parvalbumin-specific antibodies that can be used for allergen detection and for mapping of conserved epitopes.

  17. Design of single-polarization coupler based on dual-core photonic band-gap fiber implied in resonant fiber optic gyro

    Science.gov (United States)

    Xu, Zhenlong; Li, Xuyou; Zhang, Chunmei; Ling, Weiwei; Liu, Pan; Xia, Linlin; Yang, Hanrui

    2016-12-01

    A novel (to our knowledge) type of single-polarization (SP) coupler based on a dual-core photonic band-gap fiber (PBF) is proposed. The effects of structure parameters on the performance of this coupler are studied numerically based on the full vector finite element method (FEM). Finally, an optimal design with a length of 0.377 mm at the wavelength of 1.55 μm is achieved, and its implication in PBF-based fiber ring resonator (FRR), the effect of angular misalignment on the SP coupler are analyzed as well. When the SP coupler is incorporated into a PBF-based FRR, it functions as the power splitter and the polarizer simultaneously, and can extinct the secondary eigenstate of polarization (ESOP) propagating in the FRR. The mode field of SP coupler can match with the polarization-maintaining (PM) PBF with ultra-low temperature sensitivity proposed in previous study, and an all PM-PBF based FRR can be established, which is of great significance in suppressing the temperature-related polarization fluctuation and improving the long-term stability for RFOG, and the SP coupler has high angular misalignment tolerance as well.

  18. Long-lasting changes in brain activation induced by a single REAC technology pulse in Wi-Fi bands. Randomized double-blind fMRI qualitative study.

    Science.gov (United States)

    Rinaldi, Salvatore; Mura, Marco; Castagna, Alessandro; Fontani, Vania

    2014-07-11

    The aim of this randomized double-blind study was to evaluate in healthy adult subjects, with functional magnetic resonance imaging (fMRI), long lasting changes in brain activation patterns following administration of a single, 250 milliseconds pulse emitted with radio-electric asymmetric conveyer (REAC) technology in the Wi-Fi bands. The REAC impulse was not administered during the scan, but after this, according to a protocol that has previously been demonstrated to be effective in improving motor control and postural balance, in healthy subjects and patients. The study was conducted on 33 healthy volunteers, performed with a 1.5 T unit while operating a motor block task involving cyclical and alternating flexion and extension of one leg. Subsequently subjects were randomly divided into a treatment and a sham treatment control group. Repeated fMRI examinations were performed following the administration of the REAC pulse or sham treatment. The Treated group showed cerebellar and ponto-mesencephalic activation components that disappeared in the second scan, while these activation components persisted in the Sham group. This study shows that a very weak signal, such as 250 milliseconds Wi-Fi pulse, administered with REAC technology, could lead to lasting effects on brain activity modification.

  19. Pharmacokinetics and Tolerability of Single-Ascending Doses of Desvenlafaxine Administered to Children and Adolescents with Major Depressive Disorder.

    Science.gov (United States)

    Findling, Robert L; Groark, James; Tourian, Karen A; Ramaker, Sara A; Chiles, Deborah; Yang, Lingfeng; Nichols, Alice I

    2016-12-01

    To investigate the safety and pharmacokinetic profile of ascending doses of desvenlafaxine in children and adolescents with major depressive disorder. Assessment of the effect of desvenlafaxine on depression symptoms was exploratory. The 8-week, open-label study included an initial 3.5-day inpatient period followed by a 7.5-week outpatient period. Children (7-11 years) received a single desvenlafaxine dose of 10, 25, 50, or 100 mg on day 1; adolescents (12-17 years) received desvenlafaxine 25, 50, 100, or 200 mg/day. Plasma and urine samples were collected over the initial 72-hour inpatient period. Evaluations included treatment-emergent adverse events (TEAEs), physical examinations (including Tanner Staging), vital signs, laboratory assessments, 12-lead electrocardiogram, Columbia-Suicide Severity Rating Scale, and the Children's Depression Rating Scale-Revised (CDRS-R). In all, 29 children and 30 adolescents took at least one dose of desvenlafaxine and were included in the safety population (children: 10 mg, n = 6; 25 mg, n = 7; 50 mg, n = 9; 100 mg, n = 7; adolescents: 25 mg, n = 7; 50 mg, n = 7; 100 mg, n = 8; 200 mg, n = 8). Total area under the drug concentration-time curve from 0 to infinity (AUC) appeared to increase linearly with increasing dose. Mean (standard deviation [SD]) AUC ranged from 628 (346) ng/mL (desvenlafaxine 10 mg) to 6732 (3031) ng/mL (100 mg) in children and from 1123 (361) ng/mL (25 mg) to 11,730 (3113) ng/mL (200 mg) in adolescents. During the combined inpatient and outpatient period, 16/29 (55%) children and 21/30 (70%) adolescents reported at least one TEAE. One serious adverse event (suicidal behavior) was reported. Mean (SD) change from baseline in CDRS-R total scores at week 8 was -19.00 (9.87) for children and -21.57 (11.50) for adolescents. Desvenlafaxine AUC values increased linearly with dose; body weight alone provided an adequate prediction for dose-normalized AUC

  20. 1-Pb/s (32 SDM/46 WDM/768 Gb/s) C-band Dense SDM Transmission over 205.6-km of Single-mode Heterogeneous Multi-core Fiber using 96-Gbaud PDM-16QAM Channels

    DEFF Research Database (Denmark)

    Kobayashi, Takayuki; Nakamura, M.; Hamaoka, F.

    2017-01-01

    We demonstrate the first 1-Pb/s unidirectional inline-amplified transmission over 205.6-km of single-mode 32-core fiber within C-band only. 96-Gbaud LDPC-coded PDM-16QAM channels with FEC redundancy of 12.75% realize high-aggregate spectral efficiency of 217.6 b/s/Hz......We demonstrate the first 1-Pb/s unidirectional inline-amplified transmission over 205.6-km of single-mode 32-core fiber within C-band only. 96-Gbaud LDPC-coded PDM-16QAM channels with FEC redundancy of 12.75% realize high-aggregate spectral efficiency of 217.6 b/s/Hz...

  1. Biochemical Markers of Bone Turnover in Patients with β-Thalassemia Major: A Single Center Study from Southern Pakistan

    Directory of Open Access Journals (Sweden)

    Sadia Sultan

    2016-01-01

    Full Text Available Objectives. Skeletal complications in β-homozygous thalassemic patients are uncommon but often debilitating, even amongst children and adolescent patients with well maintained transfusion and chelation therapy. The aim is to evaluate the biochemical markers of bone turnover in regularly transfused thalassemic patients and its possible correlations with demographic data and hematological and biochemical markers. Methods. In this prospective cross-sectional study, 36 β-thalassemia major patients were enrolled from March 2012 to March 2014. All patients underwent complete blood counts, LFTs, serum ferritin, serum calcium, phosphorus, serum albumin, alkaline phosphatase, 25-OH vitamin D, and parathormone (PTH levels. Results. There were 17 males and 19 females with mean age of 12.56 ± 5.9 years. Hypocalcemia and hypophosphatemia were seen in 66.6% and 19.4%, respectively, while 25-OH vitamin D deficiency was present in 72.2% of thalassemic children and adolescents. Hypoparathyroidism was seen in 13.8% while hyperparathyroidism was detected in 8.3% of patients. There was direct correlation between serum phosphorus and ferritin levels (P0.05. Conclusions. Biochemical profile is significantly altered in patients with β-thalassemia major and bone associated biochemical abnormalities like hypocalcaemia, 25-OH vitamin D deficiency, and hypophosphatemia are not uncommon in Pakistani patients with thalassemia major.

  2. Benefit of extracorporeal membrane oxygenation in major burns after stun grenade explosion: Experience from a single military medical center.

    Science.gov (United States)

    Hsu, Po-Shun; Tsai, Yi-Ting; Lin, Chih-Yuan; Chen, Shyi-Gen; Dai, Niann-Tzyy; Chen, Cheng-Jung; Chen, Jia-Lin; Tsai, Chien-Sung

    2017-05-01

    Explosion injury is very common on the battlefield and is associated with major burn and inhalation injuries and subsequent high mortality and morbidity rates. Here we report six victims who suffered from explosion injuries caused by stun grenade; all were treated with extracorporeal membrane oxygenation (ECMO) as salvage therapy. This study was aimed to evaluate the indications and efficacy of ECMO in acute and critically ill major burn patients. This was a retrospective analysis of six patients from Tri-Service General Hospital, National Defense Medical Center in Taiwan. All suffered from major burns with 89.0±19.1% average of total body surface area over second degree (TBSA; range, 50-99%). ECMO was used due to inhalation injury in five patients and cardiogenic shock in one patient. The average interval to start ECMO was 26.5±19.0h (range, 14-63h). Venoarterial ECMO was used on in four patients due to unstable hemodynamic status, whereas venovenous ECMO was used in two patients for sustained hypoxemia. All patients had rhabdomyolysis with acute renal failure. The average duration of ECMO was 169.6±180.9h (range, 27-401h). All patients developed coagulopathy and needed debridement surgery during ECMO support, and five underwent torso escharotomy due to inspiratory compromise. Only one patient whose second and third degree burns covered 50% TBSA was successfully weaned from ECMO and survived; he was discharged after 221 hospital days. All patients who died had second and third degree burns covering over 90% of their TBSA. Three patients died of multiple organ failure, one died of septic shock, and the other died of cardiogenic shock. Overall survival rate was 16.7%. In acute and critically ill major burn patients, ECMO could be considered as a salvage therapy, particularly in those with inhalation injury and burn-related acute respiratory distress syndrome. However, ECMO does not seem to provide benefits for circulatory support in those with hemodynamic

  3. Sustained weight loss and improvement of quality of life after laparoscopic adjustable gastric banding for morbid obesity: a single surgeon experience in Ireland.

    LENUS (Irish Health Repository)

    Chang, K H

    2010-03-01

    Although substantial weight loss is the primary outcome following bariatric surgery, changes in obesity-related morbidity and quality of life (QoL) are equally important. This study reports on weight loss, QoL and health outcomes following laparoscopic adjustable gastric banding (LAGB).

  4. Microsatellite and mitochondrial data provide evidence for a single major introduction for the Neartic leafhopper Scaphoideus titanus in Europe.

    Directory of Open Access Journals (Sweden)

    Daciana Papura

    Full Text Available Scaphoideus titanus, a leafhopper native to North America and invasive in Europe, is the vector of the Flavescence dorée phytoplasma, the causal agent of the most important form of grapevine yellows in European vineyards. We studied 10 polymorphic microsatellite loci and a 623 bp fragment of the mitochondrial cytochrome oxidase II gene in native S. titanus from north-eastern America and introduced European populations, to elucidate the colonization scenario. Consistent with their recent history, invasive European populations were less genetically diverse than American populations for both types of markers, suggesting a recent bottleneck. Significant isolation by distance was detected between American populations but not between European populations. None of the European mitochondrial haplotypes was found in the American vineyards, from which they are assumed to have originated. The precise source of the invasive S. titanus populations therefore remains unclear. Nevertheless, the high heterozygosity of North-East American populations (which contained 92% of the observed alleles suggests that this region is part of the native range of S. titanus. Clustering population genetics analyses with microsatellite and mitochondrial data suggested that European populations originated from a single introduction event. Most of the introduced populations clustered with populations from Long Island, the Atlantic Coast winegrowing region in which Vitis aestivalis occurs.

  5. Single Breath-Hold Physiotherapy Technique; Effective tool for T2* magnetic resonance imaging in young patients with thalassaemia major

    Directory of Open Access Journals (Sweden)

    Surekha T. Mevada

    2016-02-01

    Full Text Available Magnetic resonance imaging using T2* (MRI T2* is a highly sensitive and non-invasive technique for the detection of tissue iron load. Although the single breath-hold multi-echo T2* technique has been available at the Sultan Qaboos University Hospital (SQUH, Muscat, Oman, since 2006, it could not be performed on younger patients due to their inability to hold their breath after expiration. This study was carried out between May 2007 and May 2015 and assessed 50 SQUH thalassaemic patients aged 7‒17 years old. Seven of these patients underwent baseline and one-year follow-up MRI T2* scans before receiving physiotherapy training. Subsequently, all patients were trained by a physiotherapist to hold their breath for approximately 15‒20 seconds at the end of expiration before undergoing baseline and one-year follow-up MRI T2* scans. Failure rates for the pre- and post-training groups were 6.0% and 42.8%, respectively. These results indicate that the training of thalassaemic patients in breathhold techniques is beneficial and increases rates of compliance for MRI T2* scans.

  6. Genome-wide association study identifies a single major locus contributing to survival into old age; the APOE locus revisited

    DEFF Research Database (Denmark)

    Deelen, Joris; Beekman, Marian; Uh, Hae-Won

    2011-01-01

    (LLS) and 1670 younger population controls. The strongest candidate SNPs from this GWAS have been analyzed in a meta-analysis of nonagenarian cases from the Rotterdam Study, Leiden 85-plus study and Danish 1905 cohort. Only one of the 62 prioritized SNPs from the GWAS analysis (P ... genome-wide significance with survival into old age in the meta-analysis of 4149 nonagenarian cases and 7582 younger controls (OR = 0.71 (95% CI 0.65-0.77), P = 3.39 x 10(-17) ). This SNP, rs2075650, is located in TOMM40 at chromosome 19q13.32 close to the apolipoprotein E (APOE) gene. Although...... of the nonagenarian cases from the LLS and their partners. In addition, we observed a novel association between this locus and serum levels of IGF-1 in females (P = 0.005). In conclusion, the major locus determining familial longevity up to high age as detected by GWAS was marked by rs2075650, which tags...

  7. Prevalence of hepatitis C infection among children with β-thalassaemia major in Mid Delta, Egypt: a single centre study.

    Science.gov (United States)

    El-Shanshory, Mohamed R; Kabbash, Ibrahim A; Soliman, Hanan H; Nagy, Hala M; Abdou, Said H

    2013-04-01

    Transfusion dependant patients are at a higher risk of acquiring bloodborne infections even under conditions of safe transfusion. This study was designed to determine sero-prevalence of hepatitis C infection and possible associated risk factors in thalassaemic children. One hundred and twenty five children with β thalassaemia major (β-TM) were recruited from the Haematology/Oncology Unit, Paediatric Department, Tanta University Hospital, Egypt, between April 2010 and October 2011. Patients underwent history taking, full clinical examination, routine investigations and venous blood sampling. Serum was stored at -20°C till tested for hepatitis C (HCV Ab) and B (HBsAg) by ELISA. HCV Ab positive cases were confirmed by PCR. All patients were HBsAg negative. HCV Ab ELISA was positive in 76%, negative in 20% and equivocal in 4%. Fifty patients (40%) had positive PCR for HCV. PCR showed low viraemia in 78%, moderate viraemia in 20% and high viraemia in 2%. A positive family history of HCV, history of minor operative intervention and/or dental procedures were significantly associated with higher frequency of HCV infection in thalassaemic children, while amount and frequency of transfused blood, age at transfusion and chelation state were not. HCV infection is highly prevalent in children with β-TM in Egypt despite strict pre-transfusion blood testing. This should arouse the attention for environmental and community acquired factors. Quality management to insure infection control in minor operative procedures and adding more sensitive tests for blood screening are recommended.

  8. A single mutation in the GSTe2 gene allows tracking of metabolically based insecticide resistance in a major malaria vector.

    Science.gov (United States)

    Riveron, Jacob M; Yunta, Cristina; Ibrahim, Sulaiman S; Djouaka, Rousseau; Irving, Helen; Menze, Benjamin D; Ismail, Hanafy M; Hemingway, Janet; Ranson, Hilary; Albert, Armando; Wondji, Charles S

    2014-02-25

    Metabolic resistance to insecticides is the biggest threat to the continued effectiveness of malaria vector control. However, its underlying molecular basis, crucial for successful resistance management, remains poorly characterized. Here, we demonstrate that the single amino acid change L119F in an upregulated glutathione S-transferase gene, GSTe2, confers high levels of metabolic resistance to DDT in the malaria vector Anopheles funestus. Genome-wide transcription analysis revealed that GSTe2 was the most over-expressed detoxification gene in DDT and permethrin-resistant mosquitoes from Benin. Transgenic expression of GSTe2 in Drosophila melanogaster demonstrated that over-transcription of this gene alone confers DDT resistance and cross-resistance to pyrethroids. Analysis of GSTe2 polymorphism established that the point mutation is tightly associated with metabolic resistance to DDT and its geographical distribution strongly correlates with DDT resistance patterns across Africa. Functional characterization of recombinant GSTe2 further supports the role of the L119F mutation, with the resistant allele being more efficient at metabolizing DDT than the susceptible one. Importantly, we also show that GSTe2 directly metabolizes the pyrethroid permethrin. Structural analysis reveals that the mutation confers resistance by enlarging the GSTe2 DDT-binding cavity, leading to increased DDT access and metabolism. Furthermore, we show that GSTe2 is under strong directional selection in resistant populations, and a restriction of gene flow is observed between African regions, enabling the prediction of the future spread of this resistance. This first DNA-based metabolic resistance marker in mosquitoes provides an essential tool to track the evolution of resistance and to design suitable resistance management strategies.

  9. A single mutation in the GSTe2 gene allows tracking of metabolically based insecticide resistance in a major malaria vector

    Science.gov (United States)

    2014-01-01

    Background Metabolic resistance to insecticides is the biggest threat to the continued effectiveness of malaria vector control. However, its underlying molecular basis, crucial for successful resistance management, remains poorly characterized. Results Here, we demonstrate that the single amino acid change L119F in an upregulated glutathione S-transferase gene, GSTe2, confers high levels of metabolic resistance to DDT in the malaria vector Anopheles funestus. Genome-wide transcription analysis revealed that GSTe2 was the most over-expressed detoxification gene in DDT and permethrin-resistant mosquitoes from Benin. Transgenic expression of GSTe2 in Drosophila melanogaster demonstrated that over-transcription of this gene alone confers DDT resistance and cross-resistance to pyrethroids. Analysis of GSTe2 polymorphism established that the point mutation is tightly associated with metabolic resistance to DDT and its geographical distribution strongly correlates with DDT resistance patterns across Africa. Functional characterization of recombinant GSTe2 further supports the role of the L119F mutation, with the resistant allele being more efficient at metabolizing DDT than the susceptible one. Importantly, we also show that GSTe2 directly metabolizes the pyrethroid permethrin. Structural analysis reveals that the mutation confers resistance by enlarging the GSTe2 DDT-binding cavity, leading to increased DDT access and metabolism. Furthermore, we show that GSTe2 is under strong directional selection in resistant populations, and a restriction of gene flow is observed between African regions, enabling the prediction of the future spread of this resistance. Conclusions This first DNA-based metabolic resistance marker in mosquitoes provides an essential tool to track the evolution of resistance and to design suitable resistance management strategies. PMID:24565444

  10. Transcriptomes of major renal collecting duct cell types in mouse identified by single-cell RNA-seq.

    Science.gov (United States)

    Chen, Lihe; Lee, Jae Wook; Chou, Chung-Lin; Nair, Anil V; Battistone, Maria A; Păunescu, Teodor G; Merkulova, Maria; Breton, Sylvie; Verlander, Jill W; Wall, Susan M; Brown, Dennis; Burg, Maurice B; Knepper, Mark A

    2017-11-14

    Prior RNA sequencing (RNA-seq) studies have identified complete transcriptomes for most renal epithelial cell types. The exceptions are the cell types that make up the renal collecting duct, namely intercalated cells (ICs) and principal cells (PCs), which account for only a small fraction of the kidney mass, but play critical physiological roles in the regulation of blood pressure, extracellular fluid volume, and extracellular fluid composition. To enrich these cell types, we used FACS that employed well-established lectin cell surface markers for PCs and type B ICs, as well as a newly identified cell surface marker for type A ICs, c-Kit. Single-cell RNA-seq using the IC- and PC-enriched populations as input enabled identification of complete transcriptomes of A-ICs, B-ICs, and PCs. The data were used to create a freely accessible online gene-expression database for collecting duct cells. This database allowed identification of genes that are selectively expressed in each cell type, including cell-surface receptors, transcription factors, transporters, and secreted proteins. The analysis also identified a small fraction of hybrid cells expressing aquaporin-2 and anion exchanger 1 or pendrin transcripts. In many cases, mRNAs for receptors and their ligands were identified in different cells (e.g., Notch2 chiefly in PCs vs. Jag1 chiefly in ICs), suggesting signaling cross-talk among the three cell types. The identified patterns of gene expression among the three types of collecting duct cells provide a foundation for understanding physiological regulation and pathophysiology in the renal collecting duct.

  11. Analysis of single nucleotide polymorphisms in major and candidate genes for production traits in Nero Siciliano pig breed

    Directory of Open Access Journals (Sweden)

    Alessandro Zumbo

    2010-01-01

    Full Text Available Nero Siciliano (NS; Sicilian Black is a local pig breed reared on the island of Sicily mainly under extensive management.The breed is well adapted to marginal conditions and is appreciated for its reproductive performance, disease resistanceand production of tasty meat. For a genetic characterization of this breed we analyzed the allele frequencies of singlenucleotide polymorphisms (SNPs in eight major or candidate genes (ryanodine receptor 1, RYR1; Na+, K+ ATPase subunitα 2, ATP1A2; myosin heavy chain 2B, MYH4; sarcolipin, SLN; cathepsin B, CTSB; cystatin B, CSTB; estrogen receptor,ESR; melanocortin receptor 1, MC1R for performance and phenotypic traits. The animals that were sampled andanalyzed represent about 6-8% of the total NS pig population. PCR-RFLP or PCR-SSCP techniques were used to type theDNA markers in the selected loci. Exact test of Hardy-Weinberg equilibrium was computed for each locus, Fis statisticsand heterozygosity were calculated for each locus and over all loci. Allele frequencies obtained in NS breed were comparedto the frequencies already available in literature for the Large White, Landrace, Duroc, Belgian Landrace, Piétrain,Hampshire and Meishan breeds. For the ESR locus, as no information on the distribution of the two alleles were available,we typed a sample of unrelated pigs from the considered breeds.Even if only eight loci were studied in NS breed, important elements were obtained from the data. The 1843T (n alleleat the RYR1 locus is present in NS breed, thus the molecular test to identify the carriers of this allele should be adoptedto avoid its spreading in the population. Moreover, other studies are needed to clarify the allelic structure of the MC1Rgene, which affects coat color, in order to evaluate if this gene could be used in genetic tests for the traceability of themeat products of this breed. Finally, the present work represents an attempt to evaluate data on mutations within majorand candidate genes

  12. Crystal orientation dependent optical transmittance and band gap of Na{sub 0.5}Bi{sub 0.5}TiO{sub 3}–BaTiO{sub 3} single crystals

    Energy Technology Data Exchange (ETDEWEB)

    He, Chongjun, E-mail: hechongjun@nuaa.edu.cn [College of Science, Nanjing University of Aeronautics and Astronautics, Nanjing 211106 (China); Deng, Chenguang; Wang, Jiming; Gu, Xiaorong; Wu, Tong [College of Science, Nanjing University of Aeronautics and Astronautics, Nanjing 211106 (China); Zhu, Kongjun [State Key Laboratory of Mechanics and Control of Mechanical Structures, College of Aerospace Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China); Liu, Youwen, E-mail: ywliu@nuaa.edu.cn [College of Science, Nanjing University of Aeronautics and Astronautics, Nanjing 211106 (China); Key Laboratory of Radar Imaging and Microwave Photonics, Ministry of Education, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China)

    2016-02-15

    Optical transmittance spectra of lead-free ferroelectric (1−x)Na{sub 0.5}Bi{sub 0.5}TiO{sub 3}–xBaTiO{sub 3} (NBT–xBT) single crystals poled along different directions have been studied comprehensively. After poled along [001] direction, the transmittance of tetragonal NBT–8%BT crystal is about 70%, which is much higher than that of NBT–2%BT crystal with rhombohedral structure and NBT–5%BT crystal with morphotropic phase boundary (MPB) composition. However, after poled [111] direction, the transmittance of tetragonal NBT–8%BT crystal is the smallest among them. These properties are manifest in view of the crystal structure. Both direct and indirect optical energy band gaps, as well phonon energies were obtained from absorption coefficient spectra by Tauc equations. The band gaps of [001]-poled NBT–xBT crystals increase with BT content, yet the [111]-poled crystals have opposite trends.

  13. The number of cores taken in patients diagnosed with a single microfocus at initial biopsy is a major predictor of insignificant prostate cancer.

    Science.gov (United States)

    Villa, Luca; Capitanio, Umberto; Briganti, Alberto; Abdollah, Firas; Suardi, Nazareno; Salonia, Andrea; Gallina, Andrea; Freschi, Massimo; Russo, Andrea; Castiglione, Fabio; Bianchi, Marco; Rigatti, Patrizio; Montorsi, Francesco; Scattoni, Vincenzo

    2013-03-01

    Patients with a single microfocus of prostate cancer at initial biopsy represent the ideal candidates for active surveillance. We investigate whether the number of cores taken affects the concordance rate between microfocus of prostate cancer and the confirmation of a pathologically insignificant prostate cancer at radical prostatectomy. Data were analyzed from 233 patients with a single microfocus of prostate cancer at initial transrectal prostate biopsy (a single focus of Gleason 6 involving 5% or less of the core) subsequently treated with radical prostatectomy. The chi-square test, cubic spline analyses and logistic regression analyses were used to depict the relationship between the number of cores taken and the probability of confirming the presence of an indolent disease (pathologically confirmed insignificant prostate cancer defined as radical prostatectomy Gleason score 6 or less, tumor volume 0.5 ml or less and organ confined disease). Overall 65 patients (27.9%) showed pathologically confirmed insignificant prostate cancer at radical prostatectomy. The rate of pathologically confirmed insignificant prostate cancer was 3.8%, 29.6% and 39.4% in patients who underwent biopsy of 12 or fewer cores, 13 to 18 cores and 19 or more cores, respectively (p number of cores taken (p cancer. Of patients diagnosed with a single microfocus of prostate cancer the number of biopsy cores taken was a major independent predictor of having pathologically confirmed insignificant prostate cancer at radical prostatectomy. Therefore, when active surveillance is considered as a possible alternative in patients with microfocus of prostate cancer, the number of cores taken should be taken into account in decision making. Copyright © 2013 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  14. Prenatal diagnosis of amniotic band syndrome

    Directory of Open Access Journals (Sweden)

    Laxmi Devi Padmanabhan

    2016-01-01

    Full Text Available Amniotic band can cause a broad spectrum of anomalies ranging from simple band constrictions to major craniofacial and visceral defects. It can cause significant neonatal morbidity. Accurate diagnosis will help in the management of the present pregnancy and in counseling with regard to future pregnancies. Here we report three cases of amniotic band syndrome detected in the prenatal period.

  15. Multi-band Modelling of Appearance

    DEFF Research Database (Denmark)

    Stegmann, Mikkel Bille; Larsen, Rasmus

    2002-01-01

    the appearance of both derived feature bands and an intensity band. As a special case of feature-band augmented appearance modelling we propose a dedicated representation with applications to face segmentation. The representation addresses a major problem within face recognition by lowering the sensitivity...

  16. Multi-band Modelling of Appearance

    DEFF Research Database (Denmark)

    Stegmann, Mikkel Bille; Larsen, Rasmus

    2003-01-01

    the appearance of both derived feature bands and an intensity band. As a special case of feature-band augmented appearance modelling we propose a dedicated representation with applications to face segmentation. The representation addresses a major problem within face recognition by lowering the sensitivity...

  17. Early relapse after single auto-SCT for multiple myeloma is a major predictor of survival in the era of novel agents.

    Science.gov (United States)

    Jimenez-Zepeda, V H; Reece, D E; Trudel, S; Chen, C; Tiedemann, R; Kukreti, V

    2015-02-01

    The role of auto-SCT in the treatment of multiple myeloma (MM) in the era of novel agents continues to evolve. It is now clear that the depth of response and clinical outcomes have significantly improved as a result of the combination of these strategies. However, not all patients with MM who undergo auto-SCT are able to sustain a meaningful response and 20% of patients relapse shortly after auto-SCT. In this study, we aimed to assess the impact of early relapse (ER) after auto-SCT on OS for MM patients undergoing single auto-SCT who had received novel agent-based induction regimens. All consecutive patients with MM undergoing single auto-SCT from January 2002 to September 2012 who had novel induction therapy were evaluated. A total of 184 patients were identified. The median OS and PFS for the group of transplanted patients were 93 and 25.4 months, respectively. Median time to relapse was 17.2 months with 40% having relapsed at the time of analysis. ER (SCT) was seen in 27 (36%) out of 75 patients who had relapsed, and median OS was significantly shorter than in those with non-ER. Multivariate analysis showed ER as the major independent prognostic factor for OS. On the basis of these findings, we conclude that not only attainment of a good response, but sustainability of it, appears to be a major prognostic variable in MM in the era of novel therapy. Patients with ER post auto-SCT should biologically be characterized in prospective studies to better understand the mechanisms of resistance associated with this particular entity.

  18. Assessment of changes in regional cerebral blood flow in patients with major depression using the 99mTc-HMPAO single photon emission tomography method

    International Nuclear Information System (INIS)

    Yazici, K.; Kapucu, Oe.; Erbas, B.; Varoglu, E.; Guelec, C.; Bekdik, C.F.; Hacettepe Univ., Ankara

    1992-01-01

    Regional cerebral blood flow was investigated in 14 patients with major depression diagnosed according to the DSM-III-R criteria (six patients with single and eight patients with recurrent episodes) and in ten healthy volunteers. The mean ages of the patients and the controls were 33.5±2.7 and 31.6±2.6 years, respectively. The severity of the depression was assessed using the 17-item Hamiltonian Depression Scale (mean: 23.2±1.5). None of the patients was under medication. After administration of 500 MBq technetium-99m hexamethylpropylene amine oxime, a single photon emission tomography study was performed and then transaxial, sagittal and coronal slices were obtained. For the semiquantitative analysis of the data, the ratios of the mean counts/pixel to the whole slice were calculated for 24 regions on three consecutive transaxial slices in the orbitomeatal plane. Additionally, left/right and frontal/occipital ratios were calculated. Both sides of the temporal region had a significantly decreased cerebral blood flow (CBF) when compared to the controls. The left/right ratio of the prefrontal region was also significantly lower in the patients than in the controls. The Hamilton score had a negative correlation with blood flow in the anterofrontal and left prefrontal regions. According to our results, regional CBF seems to be decreased in the left prefrontal and in both temporal regions in major depression. The severity of depression is correlated with the reduction in CBF in the regions of the anterofrontal and left prefrontal cortex. (orig.)

  19. Characterization of InP and InGaN quantum dots for single photon sources and AlGaInAs quantum dots in intermediate band solar cells

    International Nuclear Information System (INIS)

    Kremling, Stefan

    2014-01-01

    This thesis describes the characterization of semiconductor quantum dots (QDs) in different material systems with potential applications as single photon emitters or intermediate band solar cells. All investigations were carried out by means of optical spectroscopy methods. First, the theoretical background regarding the physics of QDs with respect to their electronic structure and their associated statistical properties are presented. Especially peculiarities of photon statistics of light are explained. Moreover, a closer look at the physics of solar cells and the respective carrier transport is given. Then experimental methods, which were used to characterize the QD-samples, are briefly explained. First, the components and techniques of optical spectroscopy for the study of individual, isolated QDs are described. Second, different experimental technologies for the characterization of solar cells are discussed. The method for measuring the two-photon-absorption process is explained in detail. The section of experimental results begins with studies of individual and spectrally isolated InP QD. Due to the low surface density of one QD per μm 2 , it is possible to study the physical properties of individual QDs optically without additional lateral sample structuring. Based on power and polarization dependent measurements, various luminescence peaks of a single QD were associated with different exciton states. In addition, the QDs were tested subject to an external magnetic field in a Faraday configuration. Finally, the temporal photon statistics of a single QD was tested using autocorrelation measurement. Afterwards, InP QDs manufactured by cyclic material deposition with growth interruptions were investigated by means of PL spectroscopy. Based on excitation power and time-resolved measurements on the QD ensemble, a bimodal QD distribution of type-I and type-II band alignment was observed. In addition, different exciton states were identified on spectrally isolated

  20. Long-term outcomes of tension band wiring with a single K-wire in Rockwood type IV/V acute acromio-clavicular dislocations: 25 cases.

    Science.gov (United States)

    Lateur, G; Boudissa, M; Rubens-Duval, B; Mader, R; Rouchy, R C; Pailhé, R; Saragaglia, D

    2016-09-01

    Our objective was to evaluate the long-term functional and radiological outcomes of tension band wiring with a single K-wire for acute Rockwood types IV and V acromio-clavicular dislocation (ACD). Single-centre cross-sectional non-randomised observational cohort study of 25 shoulders treated surgically between January 2002 and December 2004, in 25 patients, 23 males and 2 females, with a mean age of 35±11years (24-46). The evaluation criteria were the absolute and weighted Constant scores, QuickDASH score, subjective shoulder value (SSV), visual analogue scale (VAS) pain score at rest and during activities, and radiographic features in clinically symptomatic patients. Mean values were as follows: follow-up, 150±17months (133-167); absolute Constant score, 88±17 (71-105); weighted Constant score, 92.5±12.5 (80-105); QuickDASH, 15.5±7 (8.5-22.5); SSV, 88±17% (71-105); VAS pain score at rest, 0.2±0.7 (0-0.9); and VAS pain score while active, 1.4±2.3 (0-3.7). The weighted Constant score was less than 70% in only 8% of patients. Of the 17 patients for whom radiographs were obtained, 8 had acromio-clavicular osteoarthritis. Mean coraco-clavicular distance was 12.3±4.3mm (8-16.6) and mean acromio-clavicular distance was 5±5mm (0-10). The recurrence rate was 8%. Tension band wiring with a single K-wire for acute acromio-clavicular dislocation reliably provides good long-term functional outcomes. Recurrences are uncommon and few patients experience symptoms (8%). IV, retrospective study. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  1. A single-component multidrug transporter of the major facilitator superfamily is part of a network that protects Escherichia coli from bile salt stress.

    Science.gov (United States)

    Paul, Stephanie; Alegre, Kamela O; Holdsworth, Scarlett R; Rice, Matthew; Brown, James A; McVeigh, Paul; Kelly, Sharon M; Law, Christopher J

    2014-05-01

    Resistance to high concentrations of bile salts in the human intestinal tract is vital for the survival of enteric bacteria such as Escherichia coli. Although the tripartite AcrAB-TolC efflux system plays a significant role in this resistance, it is purported that other efflux pumps must also be involved. We provide evidence from a comprehensive suite of experiments performed at two different pH values (7.2 and 6.0) that reflect pH conditions that E. coli may encounter in human gut that MdtM, a single-component multidrug resistance transporter of the major facilitator superfamily, functions in bile salt resistance in E. coli by catalysing secondary active transport of bile salts out of the cell cytoplasm. Furthermore, assays performed on a chromosomal ΔacrB mutant transformed with multicopy plasmid encoding MdtM suggested a functional synergism between the single-component MdtM transporter and the tripartite AcrAB-TolC system that results in a multiplicative effect on resistance. Substrate binding experiments performed on purified MdtM demonstrated that the transporter binds to cholate and deoxycholate with micromolar affinity, and transport assays performed on inverted vesicles confirmed the capacity of MdtM to catalyse electrogenic bile salt/H(+) antiport. © 2014 The Authors. Molecular Microbiology published by John Wiley & Sons Ltd.

  2. Three-Year Major Clinical Outcomes of Angiography-Guided Single Stenting Technique in Non-Complex Left Main Coronary Artery Diseases.

    Science.gov (United States)

    Kim, Yong Hoon; Her, Ae-Young; Rha, Seung-Woon; Choi, Byoung Geol; Shim, Minsuk; Choi, Se Yeon; Byun, Jae Kyeong; Li, Hu; Kim, Woohyeun; Kang, Jun Hyuk; Choi, Jah Yeon; Park, Eun Jin; Park, Sung Hun; Lee, Sunki; Na, Jin Oh; Choi, Cheol Ung; Lim, Hong Euy; Kim, Eung Ju; Park, Chang Gyu; Seo, Hong Seog; Oh, Dong Joo

    2017-10-12

    There is limited long-term comparative clinical outcome data concerning angiography- versus intravascular ultrasound (IVUS)-guided percutaneous coronary intervention (PCI) in non-complex left main coronary artery (LMCA) disease treated with the single stenting technique in the drug-eluting stent (DES) era.The aim of this study was to investigate whether angiography-guided stenting is comparable to IVUS-guided stenting during 3-year clinical follow-up periods in patients with non-complex LM disease treated with the single stenting technique.A total of 196 patients treated with either angiography-guided (n = 74) or IVUS-guided (n = 122) PCI were included. The primary outcome was the occurrence of major adverse cardiac events (MACE) defined as total death, non-fatal myocardial infarction (MI), target lesion revascularization (TLR), target vessel revascularization (TVR), and non-target vessel revascularization (Non-TVR). To adjust for any potential confounders, propensity score (PS) adjusted analysis was performed.During 3-year follow-up, the PS adjusted Cox-proportional hazard ratio (HR) was not significantly different between the two groups for total death, cardiac death, and MI. Also, TLR and the combined rates of TVR and non-TVR were not significantly different. Finally, MACE was not significantly different between the two groups (HR: 0.63, 95% Confidence interval (CI): 0.33-1.17; P = 0.149).Angiography-guided PCI for non-complex LMCA diseases treated with the single stenting technique showed comparable results compared with IVUS-guided PCI in reducing clinical events during 3-year clinical follow-up in the DES era. Although IVUS guided PCI is the ideal strategy, angiography-guided PCI can be an option for LMCA PCI in some selected cases.

  3. Association of a specific major histocompatibility complex class IIβ single nucleotide polymorphism with resistance to lactococcosis in rainbow trout, Oncorhynchus mykiss (Walbaum).

    Science.gov (United States)

    Colussi, S; Prearo, M; Bertuzzi, S A; Scanzio, T; Peletto, S; Favaro, L; Modesto, P; Maniaci, M G; Ru, G; Desiato, R; Acutis, P L

    2015-01-01

    Major histocompatibility complex (MHC) loci encode glycoproteins that bind to foreign peptides and initiate immune responses through their interaction with T cells. MHC class II molecules are heterodimers consisting of α and β chains encoded by extremely variable genes; variation in exon 2 is responsible for the majority of observed polymorphisms, mostly concentrated in the codons specifying the peptide-binding region. Lactococcus garvieae is the causative agent of lactococcosis, a warm-water bacterial infection pathogenic for cultured freshwater and marine fish. It causes considerable economic losses, limiting the profitability and development of fish industries in general and the intensive production of rainbow trout, Oncorhynchus mykiss (Walbaum), in particular. The disease is currently controlled with vaccines and antibiotics; however, vaccines have short-term efficacy, and increasing concerns regarding antibiotic residues have called for alternative strategies. To explore the involvement of the MHC class II β-1 domain as a candidate gene for resistance to lactococcosis, we exposed 400 rainbow trout to naturally contaminated water. One single nucleotide polymorphism (SNP) and one haplotype were associated with resistance (P trout resistant to lactococcosis. © 2014 John Wiley & Sons Ltd.

  4. Single i.v. ketamine augmentation of newly initiated escitalopram for major depression: results from a randomized, placebo-controlled 4-week study.

    Science.gov (United States)

    Hu, Y-D; Xiang, Y-T; Fang, J-X; Zu, S; Sha, S; Shi, H; Ungvari, G S; Correll, C U; Chiu, H F K; Xue, Y; Tian, T-F; Wu, A-S; Ma, X; Wang, G

    2016-02-01

    While oral antidepressants reach efficacy after weeks, single-dose intravenous (i.v.) ketamine has rapid, yet time-limited antidepressant effects. We aimed to determine the efficacy and safety of single-dose i.v. ketamine augmentation of escitalopram in major depressive disorder (MDD). Thirty outpatients with severe MDD (17-item Hamilton Rating Scale for Depression total score ⩾ 24) were randomized to 4 weeks double-blind treatment with escitalopram 10 mg/day+single-dose i.v. ketamine (0.5 mg/kg over 40 min) or escitalopram 10 mg/day + placebo (0.9% i.v. saline). Depressive symptoms were measured using the Montgomery-Asberg Depression Rating Scale (MADRS) and the Quick Inventory of Depressive Symptomatology - Self-Report (QIDS-SR). Suicidal ideation was evaluated with the QIDS-SR item 12. Adverse psychopathological effects were measured with the Brief Psychiatric Rating Scale (BPRS)-positive symptoms, Young Mania Rating Scale (YMRS) and Clinician Administered Dissociative States Scale (CADSS). Patients were assessed at baseline, 1, 2, 4, 24 and 72 h and 7, 14, 21 and 28 days. Time to response (⩾ 50% MADRS score reduction) was the primary outcome. By 4 weeks, more escitalopram + ketamine-treated than escitalopram + placebo-treated patients responded (92.3% v. 57.1%, p = 0.04) and remitted (76.9% v. 14.3%, p = 0.001), with significantly shorter time to response [hazard ratio (HR) 0.04, 95% confidence interval (CI) 0.01-0.22, p escitalopram + placebo, escitalopram + ketamine was associated with significantly lower MADRS scores from 2 h to 2 weeks [(peak = 3 days-2 weeks; effect size (ES) = 1.08-1.18)], QIDS-SR scores from 2 h to 2 weeks (maximum ES = 1.27), and QIDS-SR suicidality from 2 to 72 h (maximum ES = 2.24). Only YMRS scores increased significantly with ketamine augmentation (1 and 2 h), without significant BPRS or CADSS elevation. Single-dose i.v. ketamine augmentation of escitalopram was safe and effective in severe MDD, holding promise for speeding up

  5. Progress and Prospect of the Growth of Wide-Band-Gap Group III Nitrides: Development of the Growth Method for Single-Crystal Bulk GaN

    Science.gov (United States)

    Amano, Hiroshi

    2013-05-01

    Thin films of III-V compound semiconductors such as GaAs and InP can be grown on native substrates, whereas such growth was difficult for group III nitride semiconductors. Despite this drawback, scientists have gradually become able to use the functions of group III nitride semiconductors by growing their thin films on non-native substrates such as sapphire and Si substrates. With the continuously increasing demand for the conservation and generation of energy, bulk substrates of group III nitride semiconductors are highly expected to maximize their potential. In this report, I review the current status of the growth methods for bulk GaN single crystals used for substrates as well as summarize the characteristics of blue light-emitting diodes (LEDs), heterojunction field-effect transistors (HFETs), and photovoltaic cells on GaN substrates.

  6. A compounded rare-earth iron garnet single crystal exhibiting stable Faraday rotation against wavelength and temperature variation in the 1.55 μm band

    International Nuclear Information System (INIS)

    Xu, Z.C.; Huang, M.; Li Miao

    2006-01-01

    The Bi, Tb and Yb partially substituted iron garnet bulk single crystals of Tb 3- x - y Yb y Bi x Fe 5 O 12 were grown by using Bi 2 O 3 /B 2 O 3 as flux and accelerated crucible rotation technique for single-crystal growth. Faraday rotation (FR) spectra showed that the specific FR of the (Tb 0.91 Yb 1.38 Bi 0.71 )Fe 5 O 12 crystal under magnetic field at saturation was measured to be about -1617 o /cm at λ=1.55 μm, Faraday rotation wavelength coefficient (FWC, 0.009%/nm) in the wavelength range of 1.50-1.62 μm and Faraday rotation temperature coefficient (FTC, 3.92x10 -5 /K) at λ=1.55 μm were even smaller than that of YIG. It is proven that through combining two types of Bi-substituted rare-earth iron garnets with opposite FWC and FTC signs, the compound rare-earth iron garnets with low FWC and FTC may be obtained due to the compensation effect. The saturation magnetization of (Tb 0.91 Yb 1.38 Bi 0.71 ) Fe 5 O 12 crystal is 0.48x10 6 A/M and is also much smaller than that of YIG. We have found empirically that there is a simple relationship between the FR θ f (x) and Bi content x for Tb 3- x - y Yb y Bi x Fe 5 O 12 , which is given by θ f (x)=(-2759x+400) o /cm

  7. A Study of the Relationship between Selected Non-music Major Eastern Kentucky University Students' High School Musical-Athletic Backgrounds and their Knowledge, Preferences, and Opinions of the Eastern Kentucky University Marching Band.

    Science.gov (United States)

    Taylor, Thomas C.

    This study measures the knowledge, preferences, and opinions of Eastern Kentucky University football fans about their marching band and relates high school musical and/or athletic experience to those preferences. Data was obtained from a questionnaire distributed to a sample of the student body. The results indicate that people with musical…

  8. HYBASE : HYperspectral BAnd SElection

    NARCIS (Netherlands)

    Schwering, P.B.W.; Bekman, H.H.P.T.; Seijen, H.H. van

    2009-01-01

    Band selection is essential in the design of multispectral sensor systems. This paper describes the TNO hyperspectral band selection tool HYBASE. It calculates the optimum band positions given the number of bands and the width of the spectral bands. HYBASE is used to assess the minimum number of

  9. Can we settle with single-band radiometric temperature monitoring during hyperthermia treatment of chestwall recurrence of breast cancer using a dual-mode transceiving applicator?

    International Nuclear Information System (INIS)

    Jacobsen, Svein; Stauffer, Paul R

    2007-01-01

    The total thermal dose that can be delivered during hyperthermia treatments is frequently limited by temperature heterogeneities in the heated tissue volume. Reliable temperature information on the heated area is thus vital for the optimization of clinical dosimetry. Microwave radiometry has been proposed as an accurate, quick and painless temperature sensing technique for biological tissue. Advantages include the ability to sense volume-averaged temperatures from subsurface tissue non-invasively, rather than with a limited set of point measurements typical of implanted temperature probes. We present a procedure to estimate the maximum tissue temperature from a single radiometric brightness temperature which is based on a numerical simulation of 3D tissue temperature distributions induced by microwave heating at 915 MHz. The temperature retrieval scheme is evaluated against errors arising from unknown variations in thermal, electromagnetic and design model parameters. Whereas realistic deviations from base values of dielectric and thermal parameters have only marginal impact on performance, pronounced deviations in estimated maximum tissue temperature are observed for unanticipated variations of the temperature or thickness of the bolus compartment. The need to pay particular attention to these latter applicator construction parameters in future clinical implementation of the thermometric method is emphasized

  10. A New Wide-Band Double-Negative Metamaterial for C- and S-Band Applications.

    Science.gov (United States)

    Hossain, Md Ikbal; Faruque, Mohammad Rashed Iqbal; Islam, Mohammad Tariqul; Ullah, Mohammad Habib

    2014-12-25

    A new design and analysis of a wide-band double-negative metamaterial, considering a frequency range of 0.5 to 7 GHz, is presented in this paper. Four different unit cells with varying design parameters are analyzed to evaluate the effects of the unit-cell size on the resonance frequencies of the metamaterial. Moreover, open and interconnected 2 × 2 array structures of unit cells are analyzed. The finite-difference time-domain (FDTD) method, based on the Computer Simulation Technology (CST) Microwave Studio, is utilized in the majority of this investigation. The experimental portion of the study was performed in a semi-anechoic chamber. Good agreement is observed between the simulated and measured S parameters of the developed unit cell and array. The designed unit cell exhibits negative permittivity and permeability simultaneously at S-band (2.95 GHz to 4.00 GHz) microwave frequencies. In addition, the designed unit cell can also operate as a double-negative medium throughout the C band (4.00 GHz to 4.95 GHz and 5.00 GHz to 5.57 GHz). At a number of other frequencies, it exhibits a single negative value. The two array configurations cause a slight shift in the resonance frequencies of the metamaterial and hence lead to a slight shift of the single- and double-negative frequency ranges of the metamaterial.

  11. The single and synergistic effects of the major tea components caffeine, epigallocatechin-3-gallate and L-theanine on rat sperm viability.

    Science.gov (United States)

    Dias, Tânia R; Alves, Marco G; Casal, Susana; Silva, Branca M; Oliveira, Pedro F

    2016-03-01

    Caffeine, epigallocatechin-3-gallate (EGCG) and L-theanine are the major components of tea (Camellia sinensis L.) and the main representatives of the classes of methylxanthines, catechins and free amino acids present in this beverage. There are many studies reporting tea's health benefits, however it is not clear if those effects are mediated by a single component or a synergistic action. This study aimed to evaluate the individual and synergistic effects of tea's major components on rat epididymal spermatozoa survival and oxidative profile during 3-day storage at room temperature (RT). For that, spermatozoa were incubated with caffeine (71 μg mL(-1)), EGCG (82 μg mL(-1)), or L-theanine (19 μg mL(-1)), alone or in combination. Spermatozoa viability was assessed by the eosin-nigrosin staining technique. The oxidative profile was established by evaluating the levels of carbonyl groups, protein nitration and lipid peroxidation. Supplementation of sperm storage medium with the three compounds together improved sperm viability, after 24, 48 and 72 h of incubation, relative to the control and the groups incubated with each component individually. However, at the end of the 72 h of incubation, there was an increase in protein oxidation in the group exposed to the three compounds, illustrating that the combined treatment triggers different alterations in sperm proteins during their maturational process in the epididymis. This study highlights the importance of the synergism between tea components for the beneficial effects usually attributed to this beverage, particularly in sperm storage at RT.

  12. A Single CRISPR-Cas9 Deletion Strategy that Targets the Majority of DMD Patients Restores Dystrophin Function in hiPSC-Derived Muscle Cells.

    Science.gov (United States)

    Young, Courtney S; Hicks, Michael R; Ermolova, Natalia V; Nakano, Haruko; Jan, Majib; Younesi, Shahab; Karumbayaram, Saravanan; Kumagai-Cresse, Chino; Wang, Derek; Zack, Jerome A; Kohn, Donald B; Nakano, Atsushi; Nelson, Stanley F; Miceli, M Carrie; Spencer, Melissa J; Pyle, April D

    2016-04-07

    Mutations in DMD disrupt the reading frame, prevent dystrophin translation, and cause Duchenne muscular dystrophy (DMD). Here we describe a CRISPR/Cas9 platform applicable to 60% of DMD patient mutations. We applied the platform to DMD-derived hiPSCs where successful deletion and non-homologous end joining of up to 725 kb reframed the DMD gene. This is the largest CRISPR/Cas9-mediated deletion shown to date in DMD. Use of hiPSCs allowed evaluation of dystrophin in disease-relevant cell types. Cardiomyocytes and skeletal muscle myotubes derived from reframed hiPSC clonal lines had restored dystrophin protein. The internally deleted dystrophin was functional as demonstrated by improved membrane integrity and restoration of the dystrophin glycoprotein complex in vitro and in vivo. Furthermore, miR31 was reduced upon reframing, similar to observations in Becker muscular dystrophy. This work demonstrates the feasibility of using a single CRISPR pair to correct the reading frame for the majority of DMD patients. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Risk stratifying chest pain patients in the emergency department using HEART, GRACE and TIMI scores, with a single contemporary troponin result, to predict major adverse cardiac events.

    Science.gov (United States)

    Reaney, Peter D W; Elliot, Hamish I; Noman, Awsan; Cooper, Jamie G

    2018-04-05

    The majority of patients presenting to the ED with cardiac sounding chest pain have a non-diagnostic ECG and the problem of differentiating those suffering an acute coronary syndrome from those without is familiar to all ED clinical staff. To stratify risk in these patients, specific scores have been developed. Recent work has focused on incorporating newer high-sensitivity cardiac troponin (hs-cTn) assays; however, issues regarding performance and availability of these assays remain. Prospectively compare HEART, Global Registry of Acute Coronary Events (GRACE) and Thrombolysis in Myocardial Infarction (TIMI) scores, using a single contemporary cTn at admission, to predict a major adverse cardiac event (MACE) at 30 days. Prospective observational cohort study performed in a UK tertiary hospital in patients with suspected cardiac chest pain and no significant ST elevation on initial ECG. Data collection took place 2 December 2014 to 8 February 2016. The treating clinician recorded risk score data real time and a single contemporary cTn taken at presentation was used in score calculation. The primary endpoint was 30-day MACE. C-statistic was determined for each score and diagnostic characteristics of high-risk and low-risk cut-offs were calculated. 189/1000 patients in the study developed a 30-day MACE. The c-statistic of HEART for 30-day MACE (0.87 (95% CI 0.84 to 0.90)) was higher than TIMI (0.78 (95% CI 0.74 to 0.81)) and GRACE (0.74 (95% CI 0.70 to 0.78)).HEART score ≤3 identified low-risk patients with sensitivity 99.5% (95% CI 97.1% to 99.9%) and negative predictive value (NPV) 99.6% (95% CI 97.3% to 99.9%) exceeding TIMI 0 (sensitivity 97.4% (95% CI 93.9% to 99.1%) and NPV 97.8% (95% CI 94.8% to 99.1%)) and GRACE score 0-55 (sensitivity 95.2% (95% CI 91.1% to 97.8%) and NPV 95.8% (95% CI 92.2% to 97.7%)). HEART outperformed both TIMI and GRACE in overall discriminative capacity for 30-day MACE. Using a single contemporary cTn at presentation, a HEART score

  14. Produção de biomassa de Pfaffia glomerata (Spreng. Pedersen e Plantago major L. em cultivo solteiro e consorciado Pfaffia glomerata (Spreng. Pedersen and Plantago major L. biomass production in single culture and intercropped

    Directory of Open Access Journals (Sweden)

    Eduardo Xavier do Nascimento

    2007-06-01

    Full Text Available O objetivo do trabalho foi avaliar a capacidade produtiva da Pfaffia glomerata (Spreng. Pedersen e de Plantago major L., em cultivo solteiro e consorciado. Os tratamentos em estudo foram três e quatro fileiras de plantas de tansagem por canteiro, duas fileiras de fáfia espaçadas de 36 cm ou de 54 cm, três fileiras de tansagem alternadas com duas fileiras de fáfia (36 cm-T3F36 e quatro fileiras de tansagem alternadas com duas fileiras de fáfia (54 cm-T4F54. Foi utilizado o delineamento blocos casualizados, com quatro repetições. Os espaçamentos entre plantas foram de 40 cm para fáfia e de 30 cm para tansagem. O tipo de cultivo e os espaçamentos entre fileiras não influenciaram significativamente a produção de massa fresca e seca da parte aérea e das raízes da fáfia. Na tansagem foi observado efeito significativo da forma de cultivo em todas as características avaliadas e do número de fileiras para o número de pendões. As alturas máximas das plantas de fáfia foram de 185 cm e 183 cm, aos 172 e 164 dias após o transplante, sob cultivo solteiro, nos espaçamentos de 54 cm e 36 cm, respectivamente. A razão de área equivalente (RAE, para o consórcio T3F36 foi de 1,07 e para o T4F54 foi de 1,50. No caso de recomendação agronômica, optar-se-ía pelo consórcio T4F54.This study aimed to evaluate the production of Pfaffia glomerata (Spreng. Pedersen and Plantago major biomass in sole culture and intercropped. The treatments in study were three and four rows of plants of common plant for plat, two rows of Pfaffia glomerata spaced of 36 cm or 54 cm, three rows of common plant alternated with two rows of Pfaffia glomerata (36 cm-T3F3(6 and four alternated rows of common plant with two rows of Pfaffia glomerata (54 cm-T4F54. The experimental was desigm randomized blocks, with four replications. The spacing between plants was 40 cm for Pfaffia glomerata and 30 cm for common plant. The culture type and spacing between rows did not

  15. The effect of a single blood meal on the phenotypic expression of insecticide resistance in the major malaria vector Anopheles funestus

    Directory of Open Access Journals (Sweden)

    Coetzee Maureen

    2008-10-01

    Full Text Available Abstract Background Anopheles funestus is a major malaria vector in southern Africa. Vector control relies on the use of insecticide chemicals to significantly reduce the number of malaria vectors by targeting that portion of the female population that takes blood meals and subsequently rests indoors. It has been suggested that the intake of a blood meal may assist female mosquitoes to tolerate higher doses of insecticide through vigour tolerance. It is hypothesized that during the process of blood digestion, detoxification mechanisms required for the neutralizing of harmful components in the blood meal may also confer an increased ability to tolerate insecticide intoxication through increased enzyme regulation. Methods Bottle bioassays using a range of concentrations of the pyrethroid insecticide permethrin were performed on pyrethroid susceptible and resistant laboratory strains of An. funestus in order to detect differences in insecticide susceptibility following a single blood meal. Based on these results, a discriminating dosage was identified (double the lowest dosage that resulted in 100% mortality of the susceptible strain. Blood-fed and unfed females drawn from the resistant strain of An. funestus were then assayed against this discriminating dose, and the percentage mortality for each sample was scored and compared. Results In the insecticide dose response assays neither the fully susceptible nor the resistant strain of An. funestus showed any significant difference in insecticide susceptibility following a blood meal, regardless of the stage of blood meal digestion. A significant increase in the level of resistance was however detected in the resistant An. funestus strain following a single blood meal, based on exposure to a discriminating dose of permethrin. Conclusion The fully susceptible An. funestus strain did not show any significant alteration in susceptibility to insecticide following a blood meal suggesting that vigour

  16. The effect of a single blood meal on the phenotypic expression of insecticide resistance in the major malaria vector Anopheles funestus

    Science.gov (United States)

    Spillings, Belinda L; Coetzee, Maureen; Koekemoer, Lizette L; Brooke, Basil D

    2008-01-01

    Background Anopheles funestus is a major malaria vector in southern Africa. Vector control relies on the use of insecticide chemicals to significantly reduce the number of malaria vectors by targeting that portion of the female population that takes blood meals and subsequently rests indoors. It has been suggested that the intake of a blood meal may assist female mosquitoes to tolerate higher doses of insecticide through vigour tolerance. It is hypothesized that during the process of blood digestion, detoxification mechanisms required for the neutralizing of harmful components in the blood meal may also confer an increased ability to tolerate insecticide intoxication through increased enzyme regulation. Methods Bottle bioassays using a range of concentrations of the pyrethroid insecticide permethrin were performed on pyrethroid susceptible and resistant laboratory strains of An. funestus in order to detect differences in insecticide susceptibility following a single blood meal. Based on these results, a discriminating dosage was identified (double the lowest dosage that resulted in 100% mortality of the susceptible strain). Blood-fed and unfed females drawn from the resistant strain of An. funestus were then assayed against this discriminating dose, and the percentage mortality for each sample was scored and compared. Results In the insecticide dose response assays neither the fully susceptible nor the resistant strain of An. funestus showed any significant difference in insecticide susceptibility following a blood meal, regardless of the stage of blood meal digestion. A significant increase in the level of resistance was however detected in the resistant An. funestus strain following a single blood meal, based on exposure to a discriminating dose of permethrin. Conclusion The fully susceptible An. funestus strain did not show any significant alteration in susceptibility to insecticide following a blood meal suggesting that vigour tolerance through increased body

  17. Single Strand Annealing Plays a Major Role in RecA-Independent Recombination between Repeated Sequences in the Radioresistant Deinococcus radiodurans Bacterium.

    Directory of Open Access Journals (Sweden)

    Solenne Ithurbide

    2015-10-01

    Full Text Available The bacterium Deinococcus radiodurans is one of the most radioresistant organisms known. It is able to reconstruct a functional genome from hundreds of radiation-induced chromosomal fragments. Our work aims to highlight the genes involved in recombination between 438 bp direct repeats separated by intervening sequences of various lengths ranging from 1,479 bp to 10,500 bp to restore a functional tetA gene in the presence or absence of radiation-induced DNA double strand breaks. The frequency of spontaneous deletion events between the chromosomal direct repeats were the same in recA+ and in ΔrecA, ΔrecF, and ΔrecO bacteria, whereas recombination between chromosomal and plasmid DNA was shown to be strictly dependent on the RecA and RecF proteins. The presence of mutations in one of the repeated sequence reduced, in a MutS-dependent manner, the frequency of the deletion events. The distance between the repeats did not influence the frequencies of deletion events in recA+ as well in ΔrecA bacteria. The absence of the UvrD protein stimulated the recombination between the direct repeats whereas the absence of the DdrB protein, previously shown to be involved in DNA double strand break repair through a single strand annealing (SSA pathway, strongly reduces the frequency of RecA- (and RecO- independent deletions events. The absence of the DdrB protein also increased the lethal sectoring of cells devoid of RecA or RecO protein. γ-irradiation of recA+ cells increased about 10-fold the frequencies of the deletion events, but at a lesser extend in cells devoid of the DdrB protein. Altogether, our results suggest a major role of single strand annealing in DNA repeat deletion events in bacteria devoid of the RecA protein, and also in recA+ bacteria exposed to ionizing radiation.

  18. A Phase II, Multicenter, Single-Arm Study to Evaluate the Safety and Efficacy of Deferasirox after Hematopoietic Stem Cell Transplantation in Children with β-Thalassemia Major.

    Science.gov (United States)

    Yesilipek, Mehmet Akif; Karasu, Gulsun; Kaya, Zuhre; Kuskonmaz, Baris B; Uygun, Vedat; Dag, Ilkiz; Ozudogru, Onur; Ertem, Mehmet

    2018-03-01

    We conducted a prospective, phase II, multicenter, single-arm study to evaluate the efficacy and safety of deferasirox in patients age >2 to 1000 µg/L; cardiac MRI T2* deferasirox at an initial dose of 10 mg/kg/day, with up-titration to a maximum of 20 mg/kg/day. The study continued for 52 weeks and included a total of 27 patients (mean age, 9.1 ± 3.8 years; 70.4% male). One patient (3.7%) was lost to follow-up. The majority of patients (n = 20; 74.1%) were able to achieve the intended dose of 20 mg/kg/day. No deaths occurred. A total of 134 adverse events (AEs) were reported in 25 patients (92.6%) during the study. The majority of patients had grade 1 or 2 AEs, with only 8 patients (29.6%) experiencing grade 3 AEs. Only 10 AEs occurring in 4 patients (14.8%) were suspected to be related to deferasirox (ALT/AST increase, n = 4; urinary tract infection, n = 1). The deferasirox dose had to be adjusted or interrupted for 6 AEs occurring in 4 patients (14.8%). A total of 6 serious AEs occurred in 3 patients (11.1%), none of which were suspected to be related to deferasirox. From baseline to week 52, there were decreases in median concentrations of alanine aminotransferase (ALT), from 30.0 to 17.0 IU/L, and aspartate aminotransferase (AST), from 35.5 to 26.0 IU/L. Median serum creatinine and cystatin C concentrations were similar at baseline and week 52. There was a continuous and significant decrease in median serum ferritin level from 1718.0 µg/L at baseline to 845.3 µg/L following 52 weeks of therapy (P deferasirox treatment at doses up to 20 mg/kg/day reduces the iron burden in children with TM post-HSCT, with a manageable safety profile. Copyright © 2017 The American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

  19. A technetium-99m hexamethylpropylene amine oxime brain single-photon emission tomography study in adolescent patients with major depressive disorder

    International Nuclear Information System (INIS)

    Tutus, A.; Kibar, M.; Sofuoglu, S.; Basturk, M.; Goenuel, A.S.

    1998-01-01

    We have not encountered any brain single-photon emission tomography (SPET) study performed in adolescent depressed patients in the literature. Therefore, we used technetium-99m hexamethylpropylene amine oxime ( 99m Tc-HMPAO) brain SPET in adolescent patients with major depressive disorder (MDD) to examine the possible changes in cerebral perfusion and the possible association between perfusion indices and clinical variables. Fourteen adolescent out-patients (nine females, five males; mean±SD age: 13.11±1.43 years; range: 11-15 years) fulfilling the DSM-IV criteria for MDD and 11 age-matched healthy control subjects (six females, five males; mean±SD age: 13.80±1.60 years; range: 12-15 years) were included in the study. 99 Tc-HMPAO brain SPET was performed twice in the patient group and once in the control group. The first SPET investigation was performed under non-medicated conditions and the second was performed after depressive symptoms had subsided. A relative perfusion index (PI) was calculated as the ratio of regional cortical activity to the whole brain activity. We found significant differences between the PI values of the untreated depressed patients and those of the controls, indicating relatively reduced perfusion in the left anterofrontal and left temporal cortical areas. No significant differences in regional PI values were found between the remitted depressed patients and the controls. Our study suggests that adolescent patients with MDD may have regional cerebral blood flow deficits in frontal regions and a greater anterofrontal right-left perfusion asymmetry compared with normal subjects. The fact that these abnormalities in perfusion indices have a trend toward normal values with symptomatic improvement suggests that they may be state-dependent markers for adolescent MDD. (orig.)

  20. Error Analysis of Band Matrix Method

    OpenAIRE

    Taniguchi, Takeo; Soga, Akira

    1984-01-01

    Numerical error in the solution of the band matrix method based on the elimination method in single precision is investigated theoretically and experimentally, and the behaviour of the truncation error and the roundoff error is clarified. Some important suggestions for the useful application of the band solver are proposed by using the results of above error analysis.

  1. Wide band ENDOR spectrometer

    International Nuclear Information System (INIS)

    Mendonca Filho, C.

    1973-01-01

    The construction of an ENDOR spectrometer operating from 0,5 to 75 MHz within a single band, with ore Klystron and homodine detection, and no fundamental changes on the electron spin resonance spectrometer was described. The ENDOR signal can be detected both by amplitude modulation of the frequency field, or direct detection of the ESR output, which is taken to a signal analyser. The signal-to-noise ratio is raised by averaging rather than filtering avoiding the use of long time constants, providing natural line widths. The experimental apparatus and the spectra obtained are described. A discussion, relating the ENDOR line amplitudes with the experimental conditions is done and ENDOR mechanism, in which there is a relevant presence of cross relaxation is proposed

  2. Characterization of Fine Airborne Particulate Collected in Tokyo and Major Atmospheric Emission Sources by Using Single Particle Measurement of SEM-EDX

    Science.gov (United States)

    Sato, K.; Iijima, A.; Furuta, N.

    2008-12-01

    In our long-term monitoring of size-classified Airborne Particulate Matter (APM) in Tokyo since 1995, it had been demonstrated that toxic elements such as As, Se, Cd, Sb and Pb were extremely enriched in fine APM (PM2.5). However, in that study, total sampled APM on a filter was digested with acids, and thus only averaged elemental composition in fine APM could be obtained. One of the effective methods to determine the origin of APM is single particle measurement by using SEM-EDX. By using characteristic shapes observed by SEM and marker elements contained in APM measured by EDX, detailed information for source identification can be obtained. In this study, fine APM (PM2.5) was collected at various locations such as roadside, diesel vehicle exhaust, a heavy oil combustion plant and a waste incineration plant as well as ambient atmosphere in Tokyo, and characteristics of fine particles that will be utilized for identification of emission sources are elucidated. Fine particles can be classified into 3 main characteristic shape groups; edge-shaped, cotton-like and spherical. Shape of particles collected in a heavy oil combustion plant and a waste incineration plant was mostly spherical, and these particles may be associated with thermal process. Diesel exhaust particles were predominantly cotton-like which may consist of coagulated nano-sized particles. Most of brake abrasion dusts were edge-shaped, which may be associated with mechanical abrasion of brake pads. In the elemental analysis of fine particles, high concentrations of Sb, Cu, Ti and Ba were detected in brake abrasion dusts. Since these elements are major constituents of brake pads, these can be used for marker elements of brake abrasion dusts. High concentration of C was detected in diesel exhaust particles and oil combustion particles, and thus C can be used for marker elements of their origin. Furthermore, high concentrations of C, Ca and K were detected in fly ash from a waste incineration plant, which

  3. Band structure of semiconductors

    CERN Document Server

    Tsidilkovski, I M

    2013-01-01

    Band Structure of Semiconductors provides a review of the theoretical and experimental methods of investigating band structure and an analysis of the results of the developments in this field. The book presents the problems, methods, and applications in the study of band structure. Topics on the computational methods of band structure; band structures of important semiconducting materials; behavior of an electron in a perturbed periodic field; effective masses and g-factors for the most commonly encountered band structures; and the treatment of cyclotron resonance, Shubnikov-de Haas oscillatio

  4. An Exploratory Investigation of the Relationship between Turnover Intentions, Work Exhaustion and Disengagement among IT Professionals in a Single Institution of Higher Education in a Major Metropolitan Area

    Science.gov (United States)

    Ford, Valerie F.

    2012-01-01

    Recent studies have shown that turnover is a major issue in IT environments (Armstrong & Riemenschneider, 2011; Carayon, Schoepke, Hoonakker, Haims, & Brunette, 2006; Moore, 2000a; Rigas, 2009). In fact, the research literature in IT and the popular press suggest that IT professionals are particularly vulnerable to burnout (Armstrong &…

  5. Wide Band to ''Double Band'' upgrade

    International Nuclear Information System (INIS)

    Kasper, P.; Currier, R.; Garbincius, P.; Butler, J.

    1988-06-01

    The Wide Band beam currently uses electrons obtained from secondary photon conversions to produce the photon beam incident on the experimental targets. By transporting the positrons produced in these conversions as well as the electrons it is possible to almost double the number of photons delivered to the experiments per primary beam proton. 11 figs

  6. The marginal band system in nymphalid butterfly wings.

    Science.gov (United States)

    Taira, Wataru; Kinjo, Seira; Otaki, Joji M

    2015-01-01

    Butterfly wing color patterns are highly complex and diverse, but they are believed to be derived from the nymphalid groundplan, which is composed of several color pattern systems. Among these pattern systems, the marginal band system, including marginal and submarginal bands, has rarely been studied. Here, we examined the color pattern diversity of the marginal band system among nymphalid butterflies. Marginal and submarginal bands are usually expressed as a pair of linear bands aligned with the wing margin. However, a submarginal band can be expressed as a broken band, an elongated oval, or a single dot. The marginal focus, usually a white dot at the middle of a wing compartment along the wing edge, corresponds to the pupal edge spot, one of the pupal cuticle spots that signify the locations of color pattern organizing centers. A marginal band can be expressed as a semicircle, an elongated oval, or a pair of eyespot-like structures, which suggest the organizing activity of the marginal focus. Physical damage at the pupal edge spot leads to distal dislocation of the submarginal band in Junonia almana and in Vanessa indica, suggesting that the marginal focus functions as an organizing center for the marginal band system. Taken together, we conclude that the marginal band system is developmentally equivalent to other symmetry systems. Additionally, the marginal band is likely a core element and the submarginal band a paracore element of the marginal band system, and both bands are primarily specified by the marginal focus organizing center.

  7. A single point in protein trafficking by Plasmodium falciparum determines the expression of major antigens on the surface of infected erythrocytes targeted by human antibodies.

    Science.gov (United States)

    Chan, Jo-Anne; Howell, Katherine B; Langer, Christine; Maier, Alexander G; Hasang, Wina; Rogerson, Stephen J; Petter, Michaela; Chesson, Joanne; Stanisic, Danielle I; Duffy, Michael F; Cooke, Brian M; Siba, Peter M; Mueller, Ivo; Bull, Peter C; Marsh, Kevin; Fowkes, Freya J I; Beeson, James G

    2016-11-01

    Antibodies to blood-stage antigens of Plasmodium falciparum play a pivotal role in human immunity to malaria. During parasite development, multiple proteins are trafficked from the intracellular parasite to the surface of P. falciparum-infected erythrocytes (IEs). However, the relative importance of different proteins as targets of acquired antibodies, and key pathways involved in trafficking major antigens remain to be clearly defined. We quantified antibodies to surface antigens among children, adults, and pregnant women from different malaria-exposed regions. We quantified the importance of antigens as antibody targets using genetically engineered P. falciparum with modified surface antigen expression. Genetic deletion of the trafficking protein skeleton-binding protein-1 (SBP1), which is involved in trafficking the surface antigen PfEMP1, led to a dramatic reduction in antibody recognition of IEs and the ability of human antibodies to promote opsonic phagocytosis of IEs, a key mechanism of parasite clearance. The great majority of antibody epitopes on the IE surface were SBP1-dependent. This was demonstrated using parasite isolates with different genetic or phenotypic backgrounds, and among antibodies from children, adults, and pregnant women in different populations. Comparisons of antibody reactivity to parasite isolates with SBP1 deletion or inhibited PfEMP1 expression suggest that PfEMP1 is the dominant target of acquired human antibodies, and that other P. falciparum IE surface proteins are minor targets. These results establish SBP1 as part of a critical pathway for the trafficking of major surface antigens targeted by human immunity, and have key implications for vaccine development, and quantifying immunity in populations.

  8. Assessment of the financial implications for laparoscopic liver surgery: a single-centre UK cost analysis for minor and major hepatectomy.

    Science.gov (United States)

    Abu Hilal, Mohammed; Di Fabio, Francesco; Syed, Shareef; Wiltshire, Robert; Dimovska, Eleonora; Turner, David; Primrose, John N; Pearce, Neil W

    2013-07-01

    Laparoscopic hepatectomy is progressively gaining popularity. However, it is still unclear whether the laparoscopic approach offers cost advantages compared with the open approach, especially when major hepatectomies are required. Data providing useful insights into the costs of the laparoscopic approach for clinicians and hospitals are needed. The aim of this study is to assess the financial implications of the laparoscopic approach for two standardized minor and major hepatectomies: left lateral sectionectomy and right hepatectomy. A cost comparison analysis of patients undergoing laparoscopic right hepatectomy (LRH) and laparoscopic left lateral sectionectomy (LLLS) versus the open counterparts was performed. Data considered for the comparison analysis were operative costs (theatre cost, consumables and surgeon/anaesthetic labour cost), postoperative costs (hospital stay, complication management and readmissions) and overall costs. A total of 149 patients were included: 38 patients underwent LRH and 46 open right hepatectomy (ORH); 46 patients underwent LLLS and 19 open left lateral sectionectomy (OLLS). For LRH the mean operative, postoperative and overall costs were £10,181, £4,037 and £14,218; for ORH the mean operative, postoperative and overall costs were £6,483 (p costs were £5,460, £2,599 and £8,059; for OLLS the mean operative, postoperative and overall costs were £5,841 (p = 0.874), £5,796 (p cost advantage of the laparoscopic approach for left lateral sectionectomy and the cost neutrality for right hepatectomy.

  9. Band - Weg interactie

    NARCIS (Netherlands)

    de Boer, Andries; ter Huerne, Henderikus L.; Noordermeer, Jacobus W.M.; Schipper, Dirk J.; prof.dr.ir. Molenaar, A.A.A.

    2008-01-01

    De huidige infrastructuur van wegen waarover men zich snel en comfortabel kan verplaatsen is niet meer weg te denken uit onze maatschappij. Twee “componenten” die hierbij een belangrijke rol spelen zijn het wegdek en de band. Het contact tussen band en wegdek is mede bepalend voor de veiligheid. De

  10. Photonic band structure computations.

    Science.gov (United States)

    Hermann, D; Frank, M; Busch, K; Wolfle, P

    2001-01-29

    We introduce a novel algorithm for band structure computations based on multigrid methods. In addition, we demonstrate how the results of these band structure calculations may be used to compute group velocities and effective photon masses. The results are of direct relevance to studies of pulse propagation in such materials.

  11. ZEBRAFISH CHROMOSOME-BANDING

    NARCIS (Netherlands)

    PIJNACKER, LP; FERWERDA, MA

    1995-01-01

    Banding techniques were carried out on metaphase chromosomes of zebrafish (Danio rerio) embryos. The karyotypes with the longest chromosomes consist of 12 metacentrics, 26 submetacentrics, and 12 subtelocentrics (2n = 50). All centromeres are C-band positive. Eight chromosomes have a pericentric

  12. A single nucleotide polymorphism in cBIM is associated with a slower achievement of major molecular response in chronic myeloid leukaemia treated with imatinib.

    Directory of Open Access Journals (Sweden)

    Vanessa Augis

    Full Text Available BIM is essential for the response to tyrosine-kinase inhibitors (TKI in chronic myeloid leukaemia (CML patients. Recently, a deletion polymorphism in intron 2 of the BIM gene was demonstrated to confer an intrinsic TKI resistance in Asian patients. The present study aimed at identifying mutations in the BIM sequence that could lead to imatinib resistance independently of BCR-ABL mutations.BIM coding sequence analysis was performed in 72 imatinib-treated CML patients from a French population of our centre and in 29 healthy controls (reference population as a case-control study. Real-time quantitative PCR (RT qPCR was performed to assess Bim expression in our reference population.No mutation with amino-acid change was found in the BIM coding sequence. However, we observed a silent single nucleotide polymorphism (SNP c465C>T (rs724710. A strong statistical link was found between the presence of the T allele and the high Sokal risk group (p = 0.0065. T allele frequency was higher in non responsive patients than in the reference population (p = 0.0049. Similarly, this T allele was associated with the mutation frequency on the tyrosine kinase domain of BCR-ABL (pT SNP of BIM could be useful for predicting the outcome of imatinib-treated CML patients.

  13. Applying meta-pathway analyses through metagenomics to identify the functional properties of the major bacterial communities of a single spontaneous cocoa bean fermentation process sample.

    Science.gov (United States)

    Illeghems, Koen; Weckx, Stefan; De Vuyst, Luc

    2015-09-01

    A high-resolution functional metagenomic analysis of a representative single sample of a Brazilian spontaneous cocoa bean fermentation process was carried out to gain insight into its bacterial community functioning. By reconstruction of microbial meta-pathways based on metagenomic data, the current knowledge about the metabolic capabilities of bacterial members involved in the cocoa bean fermentation ecosystem was extended. Functional meta-pathway analysis revealed the distribution of the metabolic pathways between the bacterial members involved. The metabolic capabilities of the lactic acid bacteria present were most associated with the heterolactic fermentation and citrate assimilation pathways. The role of Enterobacteriaceae in the conversion of substrates was shown through the use of the mixed-acid fermentation and methylglyoxal detoxification pathways. Furthermore, several other potential functional roles for Enterobacteriaceae were indicated, such as pectinolysis and citrate assimilation. Concerning acetic acid bacteria, metabolic pathways were partially reconstructed, in particular those related to responses toward stress, explaining their metabolic activities during cocoa bean fermentation processes. Further, the in-depth metagenomic analysis unveiled functionalities involved in bacterial competitiveness, such as the occurrence of CRISPRs and potential bacteriocin production. Finally, comparative analysis of the metagenomic data with bacterial genomes of cocoa bean fermentation isolates revealed the applicability of the selected strains as functional starter cultures. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. A K/Ka band radiating element for Tx/Rx phased array

    KAUST Repository

    Sandhu, Ali Imran

    2017-01-20

    The paper presents a K/Ka band radiating element for TX/RX phased arrays. Dual band operations is obtained using a single radiating surface: a novel radiator is adopted and placed in a configuration in which dual band and single band elements are interleaved. The array elements are optimized to scan the beam in excess of 50° in both bands. A subarray with 49 Rx elements and 105 Tx elements was built and measured confirming the results obtained in simulations.

  15. S-Adenosyl-L-Methionine Augmentation in Patients with Stage II Treatment-Resistant Major Depressive Disorder: An Open Label, Fixed Dose, Single-Blind Study

    Directory of Open Access Journals (Sweden)

    Domenico De Berardis

    2013-01-01

    Full Text Available We investigated the efficacy of S-Adenosyl-L-Methionine (SAMe augmentation in patients with treatment-resistant depressive disorder (TRD. Thirty-three outpatients with major depressive episode who failed to respond to at least 8 weeks of treatment with two adequate and stable doses of antidepressants were treated openly with fixed dose of SAMe (800 mg for 8 weeks, added to existing medication. The primary outcome measure was the change from baseline in total score on Hamilton Rating Scale for Depression (HAM-D. The Clinical Global Impression of Improvement (CGI-I was rated at the endpoint. Patients with a reduction of 50% or more on HAM-D total score and a CGI-I score of 1 or 2 at endpoint were considered responders; remission was defined as a HAM-D score ≤7. Secondary outcome measures included the Snaith-Hamilton Pleasure Scale (SHAPS and the Sheehan Disability Scale (SDS. At 8 weeks, a significant decrease in HAM-D score was observed with response achieved by 60% of the patients and remission by 36%. Also a statistically significant reduction in SHAPS and SDS was observed. Our findings indicate that SAMe augmentation may be effective and well tolerated in stage II TRD. However, limitations of the present study must be considered and further placebo-controlled trials are needed.

  16. Changes in antimicrobial susceptibility and major clones of Acinetobacter calcoaceticus-baumannii complex isolates from a single hospital in Korea over 7 years.

    Science.gov (United States)

    Park, Young Kyoung; Jung, Sook-In; Park, Kyong-Hwa; Kim, Dae Hun; Choi, Ji Young; Kim, Su Hwan; Ko, Kwan Soo

    2012-01-01

    Acinetobacter species have emerged as opportunistic nosocomial pathogens in intensive care units. Epidemic spread and outbreaks of multidrug-resistant or carbapenem-resistant Acinetobacter baumannii infections have been described worldwide. Species distribution, antimicrobial resistance and genotypes were investigated for Acinetobacter species isolates collected from a single institution in Korea over 7 years. Two hundred and eighty-seven Acinetobacter species isolates were collected from patients with bloodstream infections in one Korean hospital from 2003 to 2010. Most of them belonged to the Acinetobacter calcoaceticus-baumannii complex (94.4 %). The most frequently isolated species was A. baumannii (44.2 %), followed by Acinetobacter nosocomialis (formerly Acinetobacter genomic species 13TU) (34.1 %). The proportion of A. baumannii increased significantly from 2008 to 2010 (40.4 to 50.0 %). From 2008, imipenem and meropenem resistance rates increased significantly compared with 2003-2007 (12.9 % and 20.5 %, respectively, to 41.4 % and 41.5 %, respectively). An increased carbapenem resistance rate between the two periods was identified more clearly amongst A. baumannii isolates. Polymyxin-resistant A. baumannii isolates emerged in 2008-2010, despite the availability of few isolates. The increase of carbapenem resistance in A. baumannii might be due to the substitution of main clones. Although ST92 and ST69 were the most prevalent clones amongst A. baumannii in 2003-2007 (47.8 % and 15.9 %, respectively), ST75 and ST138 had increased in 2008-2010 (39.7 % and 25.9 %, respectively). Although ST92 showed moderate resistance to carbapenems, most ST75 and ST138 isolates were resistant to carbapenems. All ST75 and ST138 isolates, but only one ST92 isolate, contained the bla(OXA-23-like) gene. Increased carbapenem resistance in Acinetobacter species and A. baumannii isolates might be due to the expansion of specific carbapenem-resistant clones.

  17. Implementation of a split-bolus single-pass CT protocol at a UK major trauma centre to reduce excess radiation dose in trauma pan-CT

    International Nuclear Information System (INIS)

    Leung, V.; Sastry, A.; Woo, T.D.; Jones, H.R.

    2015-01-01

    Aim: To quantify the dose reduction and ensure that the use of a split-bolus protocol provided sufficient vascular enhancement. Materials and methods: Between 1 January 2014 and 31 May 2014, both split bolus and traditional two-phase scans were performed on a single CT scanner (SOMATOM Definition AS+, Siemens Healthcare) using a two-pump injector (Medrad Stellant). Both protocols used Siemens' proprietary tube current and tube voltage modulation techniques (CARE dose and CARE kV). The protocols were compared retrospectively to assess the dose–length product (DLP), aortic radiodensity at the level of the coeliac axis and radiodensity of the portal vein. Results: There were 151 trauma CT examinations during this period. Seventy-eight used the split-bolus protocol. Seventy-one had traditional two-phase imaging. One patient was excluded as they were under the age of 18 years. The radiodensity measurements for the portal vein were significantly higher (p<0.001) in the split-bolus protocol. The mean aortic enhancement in both protocols exceeded 250 HU, although the traditional two-phase protocol gave greater arterial enhancement (p<0.001) than the split-bolus protocol. The split-bolus protocol had a significantly lower (p<0.001) DLP with 43.5% reduction in the mean DLP compared to the traditional protocol. Conclusion: Split-bolus CT imaging offers significant dose reduction for this relatively young population while retaining both arterial and venous enhancement. -- Highlights: •We implemented a split bolus pan-CT protocol for trauma CT. •We compared the radiation dose and vascular enhancement of the split bolus protocol to a traditional two phase protocol. •The split bolus protocol had a 43.5% reduction in mean DLP

  18. Preoperative Radiotherapy and Wide Resection for Soft Tissue Sarcomas: Achieving a Low Rate of Major Wound Complications with the Use of Flaps. Results of a Single Surgical Team

    Directory of Open Access Journals (Sweden)

    Lester Wai Mon Chan

    2018-01-01

    Full Text Available BackgroundSurgery in combination with radiotherapy (RT has become the standard of care for most soft tissue sarcomas. The choice between pre- and postoperative RT is controversial. Preoperative RT is associated with a 32–35% rate of major wound complications (MWC and 16–25% rate of reoperation. The role of vascularized soft tissue “flaps” in reducing complications is unclear. We report the outcomes of patients treated with preoperative RT, resection, and flap reconstruction.Patients and methods122 treatment episodes involving 117 patients were retrospectively reviewed. All patients were treated with 50.4 Gy of external beam radiation. Surgery was performed at 4–8 weeks after completion of RT by the same combination of orthopedic oncology and plastic reconstructive surgeon. Defects were reconstructed with 64 free and 59 pedicled/local flaps.Results30 (25% patients experienced a MWC and 17 (14% required further surgery. 20% of complications were exclusively related to the donor site. There was complete or partial loss of three flaps. There was no difference in the rate of MWC or reoperation for complications with respect to age, sex, tumor site, previous unplanned excision, tumor grade, depth, and type of flap. Tumor size ≥8 cm was associated with a higher rate of reoperation (11/44 vs 6/78; P = 0.008 but the rate of MWC was not significant (16/44 vs 14/78; P = 0.066.ConclusionThe use of soft tissue flaps is associated with a low rate of MWC and reoperation. Our results suggest that a high rate of flap usage may be required to observe a reduction in complication rates.

  19. Preoperative Radiotherapy and Wide Resection for Soft Tissue Sarcomas: Achieving a Low Rate of Major Wound Complications with the Use of Flaps. Results of a Single Surgical Team.

    Science.gov (United States)

    Chan, Lester Wai Mon; Imanishi, Jungo; Grinsell, Damien Glen; Choong, Peter

    2017-01-01

    Surgery in combination with radiotherapy (RT) has become the standard of care for most soft tissue sarcomas. The choice between pre- and postoperative RT is controversial. Preoperative RT is associated with a 32-35% rate of major wound complications (MWC) and 16-25% rate of reoperation. The role of vascularized soft tissue "flaps" in reducing complications is unclear. We report the outcomes of patients treated with preoperative RT, resection, and flap reconstruction. 122 treatment episodes involving 117 patients were retrospectively reviewed. All patients were treated with 50.4 Gy of external beam radiation. Surgery was performed at 4-8 weeks after completion of RT by the same combination of orthopedic oncology and plastic reconstructive surgeon. Defects were reconstructed with 64 free and 59 pedicled/local flaps. 30 (25%) patients experienced a MWC and 17 (14%) required further surgery. 20% of complications were exclusively related to the donor site. There was complete or partial loss of three flaps. There was no difference in the rate of MWC or reoperation for complications with respect to age, sex, tumor site, previous unplanned excision, tumor grade, depth, and type of flap. Tumor size ≥8 cm was associated with a higher rate of reoperation (11/44 vs 6/78; P  = 0.008) but the rate of MWC was not significant (16/44 vs 14/78; P  = 0.066). The use of soft tissue flaps is associated with a low rate of MWC and reoperation. Our results suggest that a high rate of flap usage may be required to observe a reduction in complication rates.

  20. Band parameters of phosphorene

    DEFF Research Database (Denmark)

    Lew Yan Voon, L. C.; Wang, J.; Zhang, Y.

    2015-01-01

    Phosphorene is a two-dimensional nanomaterial with a direct band-gap at the Brillouin zone center. In this paper, we present a recently derived effective-mass theory of the band structure in the presence of strain and electric field, based upon group theory. Band parameters for this theory...... are computed using a first-principles theory based upon the generalized-gradient approximation to the density-functional theory. These parameters and Hamiltonian will be useful for modeling physical properties of phosphorene....

  1. Tri-band optical coherence tomography for lipid and vessel spectroscopic imaging

    Science.gov (United States)

    Yu, Luoqin; Kang, Jiqiang; Wang, Xie; Wei, Xiaoming; Chan, Kin-Tak; Lee, Nikki P.; Wong, Kenneth K. Y.

    2016-03-01

    Optical coherence tomography (OCT) has been utilized for various functional imaging applications. One of its highlights comes from spectroscopic imaging, which can simultaneously obtain both morphologic and spectroscopic information. Assisting diagnosis and therapeutic intervention of coronary artery disease is one of the major directions in spectroscopic OCT applications. Previously Tanaka et al. have developed a spectral domain OCT (SDOCT) to image lipid distribution within blood vessel [1]. In the meantime, Fleming et al. have demonstrated optical frequency domain imaging (OFDI) by a 1.3-μm swept source and quadratic discriminant analysis model [2]. However, these systems suffered from burdensome computation as the optical properties' variation was calculated from a single-band illumination that provided limited contrast. On the other hand, multi-band OCT facilitates contrast enhancement with separated wavelength bands, which further offers an easier way to distinguish different materials. Federici and Dubois [3] and Tsai and Chan [4] have demonstrated tri-band OCT systems to further enhance the image contrast. However, these previous work provided under-explored functional properties. Our group has reported a dual-band OCT system based on parametrically amplified Fourier domain mode-locked (FDML) laser with time multiplexing scheme [5] and a dual-band FDML laser OCT system with wavelength-division multiplexing [6]. Fiber optical parametric amplifier (OPA) can be ideally incorporated in multi-band spectroscopic OCT system as it has a broad amplification window and offers an additional output range at idler band, which is phase matched with the signal band. The sweeping ranges can thus overcome traditional wavelength bands that are limited by intra-cavity amplifiers in FDML lasers. Here, we combines the dual-band FDML laser together with fiber OPA, which consequently renders a simultaneous tri-band output at 1.3, 1.5, and 1.6 μm, for intravascular applications

  2. Psychological benefits 2 and 4 weeks after a single treatment with near infrared light to the forehead: a pilot study of 10 patients with major depression and anxiety

    Directory of Open Access Journals (Sweden)

    Teicher Martin H

    2009-12-01

    Full Text Available Abstract Background Many studies have reported beneficial effects from the application of near-infrared (NIR light photobiomodulation (PBM to the body, and one group has reported beneficial effects applying it to the brain in stroke patients. We have reported that the measurement of a patient's left and right hemispheric emotional valence (HEV may clarify data and guide lateralized treatments. We sought to test whether a NIR treatment could 1. improve the psychological status of patients, 2. show a relationship between immediate psychological improvements when HEV was taken into account, and 3. show an increase in frontal pole regional cerebral blood flow (rCBF, and 4. be applied without side effects. Methods We gave 10 patients, (5 M/5 F with major depression, including 9 with anxiety, 7 with a past history of substance abuse (6 with an opiate abuse and 1 with an alcohol abuse history, and 3 with post traumatic stress disorder, a baseline standard diagnostic interview, a Hamilton Depression Rating Scale (HAM-D, a Hamilton Anxiety Rating Scale (HAM-A, and a Positive and Negative Affect Scale (PANAS. We then gave four 4-minute treatments in a random order: NIR to left forehead at F3, to right forehead at F4, and placebo treatments (light off at the same sites. Immediately following each treatment we repeated the PANAS, and at 2-weeks and at 4-weeks post treatment we repeated all 3 rating scales. During all treatments we recorded total hemoglobin (cHb, as a measure of rCBF with a commercial NIR spectroscopy device over the left and the right frontal poles of the brain. Results At 2-weeks post treatment 6 of 10 patients had a remission (a score ≤ 10 on the HAM-D and 7 of 10 achieved this on the HAM-A. Patients experienced highly significant reductions in both HAM-D and HAM-A scores following treatment, with the greatest reductions occurring at 2 weeks. Mean rCBF across hemispheres increased from 0.011 units in the off condition to 0.043 units in

  3. Laparoscopic gastric banding

    Science.gov (United States)

    ... eat by making you feel full after eating small amounts of food. After surgery, your doctor can adjust the band ... You will feel full after eating just a small amount of food. The food in the small upper pouch will ...

  4. HYBASE - HYperspectral BAnd SElection tool

    NARCIS (Netherlands)

    Schwering, P.B.W.; Bekman, H.H.P.T.; Seijen, H.H. van

    2008-01-01

    Band selection is essential in the design of multispectral sensor systems. This paper describes the TNO hyperspectral band selection tool HYBASE. It calculates the optimum band positions given the number of bands and the width of the spectral bands. HYBASE is used to calculate the minimum number of

  5. Hurricane Spiral Bands.

    Science.gov (United States)

    Guinn, Thomas A.; Schubert, Wayne H.

    1993-10-01

    The spiral bands that occur in tropical cyclones can be conveniently divided into two classes-outer bands and inner bands. Evidence is presented here that the outer bands form as the result of nonlinear effects during the breakdown of the intertropical convergence zone (ITCZ) through barotropic instability. In this process a zonal strip of high potential vorticity (the ITCZ shear zone or monsoon trough) begins to distort in a varicose fashion, with the potential vorticity (PV) becoming pooled in local regions that are connected by filaments of high PV. As the pooled regions become more axisymmetric, the filaments become thinner and begin to wrap around the PV centers.It is argued that inner bands form in a different manner. As a tropical cyclone intensifies due to latent heat release, the PV field becomes nearly circular with the highest values of PV in the cyclone center. The radial gradient of PV provides a state on which PV waves (the generalization of Rossby waves) can propagate. The nonlinear breaking of PV waves then leads to an irreversible distortion of the PV contours and a downgradient flux of PV. The continuation of this proem tends to erode the high PV core of the tropical cyclone, to produce a surrounding surf zone, and hence to spread the PV horizontally. In a similar fashion, inner bands can also form by the merger of a vortex with a patch of relatively high PV air. As the merger proem occurs the patch of PV is quickly elongated and wrapped around the vortex. The resulting vortex is generally larger in horizontal extent and exhibits a spiral band of PV.When the formation of outer and inner bands is interpreted in the context of a normal-mode spectral model, they emerge as slow manifold phenomena; that is, they have both rotational and (balanced or slaved) gravitational mode aspects. In this sense, regarding them as simply gravity waves leads to an incomplete dynamical picture.

  6. The Novel Microwave Stop-Band Filter

    Directory of Open Access Journals (Sweden)

    R. E. Chernobrovkin

    2008-01-01

    Full Text Available The stop-band filter with the new band-rejection element is proposed. The element is a coaxial waveguide with the slot in the centre conductor. In the frame of this research, the numerical and experimental investigations of the amplitude-frequency characteristics of the filter are carried out. It is noted that according to the slot parameters the two typical resonances (half-wave and quarter-wave can be excited. The rejection band of the single element is defined by the width, depth, and dielectric filling of the slot. Fifth-order Chebyshev filter utilizing the aforementioned element is also synthesized, manufactured, and tested. The measured and simulated results are in good agreement. The experimental filter prototype exhibits the rejection band 0.86 GHz at the level −40 dB.

  7. Major Links.

    Science.gov (United States)

    Henderson, Tona

    1995-01-01

    Provides electronic mail addresses for resources and discussion groups related to the following academic majors: art, biology, business, chemistry, computer science, economics, health sciences, history, literature, math, music, philosophy, political science, psychology, sociology, and theater. (AEF)

  8. Three-band, 1.9-μm axial resolution full-field optical coherence microscopy over a 530-1700 nm wavelength range using a single camera

    OpenAIRE

    Federici, Antoine; Dubois, Arnaud

    2014-01-01

    International audience; Full-field optical coherence microscopy is an established optical technology based on low-coherence interference microscopy for high-resolution imaging of semitransparent samples. In this Letter, we demonstrate an extension of the technique using a visible to short-wavelength infrared camera and a halogen lamp to image in three distinct bands centered at 635, 870, and 1170 nm. Reflective microscope objectives are employed to minimize chromatic aberrations of the imagin...

  9. Radio Band Observations of Blazar Variability

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... The properties of blazar variability in the radio band are studied using the unique combination of temporal resolution from single dish monitoring and spatial resolution from VLBA imaging. Such measurements now available in all four Stokes parameters, together with theoretical simulations, identify the ...

  10. Fluorescence bands and chlorophyll a forms

    NARCIS (Netherlands)

    Goedheer, J.C.

    1964-01-01

    Fluorescence spectra were determined at temperatures between 20° and −196° for a number of photosynthetic organisms. Below −90° the single fluorescence maximum around 685 mμ was replaced by a system of three bands, at 686, 696 and 717–720 mμ in algal cells. Cooling usually resulted in a decrease of

  11. Photonic band gap materials

    Science.gov (United States)

    Cassagne, D.

    Photonic band gap materials Photonic band gap materials are periodic dielectric structures that control the propagation of electromagnetic waves. We describe the plane wave method, which allows to calculate the band structures of photonic crystals. By symmetry analysis and a perturbative approach, we predict the appearance of the low energy photonic band gaps of hexagonal structures. We propose new two-dimensional structures called graphite and boron nitride. Using a transfer matrix method, we calculate the transmission of the graphite structure and we show the crucial role of the coupling with external modes. We study the appearance of allowed modes in the photonic band gap by the introduction of localized defects in the periodicity. Finally, we discuss the properties of opals formed by self-organized silica microspheres, which are very promising for the fabrication of three-dimensional photonic crystals. Les matériaux à bandes interdites photoniques sont des structures diélectriques périodiques qui contrôlent la propagation des ondes électromagnétiques. Nous décrivons la méthode des ondes planes qui permet de calculer les structures de bandes des cristaux photoniques. Par une analyse de la symétrie et une approche perturbative, nous précisons les conditions d'existence des bandes interdites de basse énergie. Nous proposons de nouvelles structures bidimensionnelles appelées graphite et nitrure de bore. Grâce à une méthode de matrices de transfert, nous calculons la transmission de la structure graphite et nous mettons en évidence le rôle fondamental du couplage avec les modes extérieurs. Nous étudions l'apparition de modes permis dans la bande interdite grâce à l'introduction de défauts dans la périodicité. Enfin, nous discutons les propriétés des opales constituées de micro-billes de silice auto-organisées, qui sont très prometteuses pour la fabrication de cristaux photoniques tridimensionnels.

  12. Restrictive techniques: gastric banding

    Directory of Open Access Journals (Sweden)

    Katia Cristina da Cunha

    2006-03-01

    Full Text Available Surgery for the treatment of severe obesity has a definite role onthe therapeutic armamentarium all over the world. Initiated 40years ago, bariatric surgery has already a long way thanks tohundred of surgeons, who had constantly searched for the besttechnique for the adequate control of severe obesity. Among theimportant breakthroughs in obesity surgery there is theadjustable gastric band. It is a sylastic band, inflatable andadjustable, which is placed on the top of the stomach in order tocreate a 15-20 cc pouch, with an outlet of 1.3cm. The adjustablegastric band has also a subcutaneous reservoir through whichadjustments can be made, according to the patient evolution.The main feature of the adjustable gastric band is the fact thatis minimal invasive, reversible, adjustable and placedlaparoscopically. Then greatly diminishing the surgical traumato the severe obese patient. Belachew and Favretti’s techniqueof laparoscopic application of the adjustable gastric band isdescribed and the evolution of the technique during this years,as we has been practiced since 1998. The perioperative care ofthe patient is also described, as well as the follow-up and shortand long term controls.

  13. Ultra wide band antennas

    CERN Document Server

    Begaud, Xavier

    2013-01-01

    Ultra Wide Band Technology (UWB) has reached a level of maturity that allows us to offer wireless links with either high or low data rates. These wireless links are frequently associated with a location capability for which ultimate accuracy varies with the inverse of the frequency bandwidth. Using time or frequency domain waveforms, they are currently the subject of international standards facilitating their commercial implementation. Drawing up a complete state of the art, Ultra Wide Band Antennas is aimed at students, engineers and researchers and presents a summary of internationally recog

  14. Reconfigurable L-Band Radar

    Science.gov (United States)

    Rincon, Rafael F.

    2008-01-01

    The reconfigurable L-Band radar is an ongoing development at NASA/GSFC that exploits the capability inherently in phased array radar systems with a state-of-the-art data acquisition and real-time processor in order to enable multi-mode measurement techniques in a single radar architecture. The development leverages on the L-Band Imaging Scatterometer, a radar system designed for the development and testing of new radar techniques; and the custom-built DBSAR processor, a highly reconfigurable, high speed data acquisition and processing system. The radar modes currently implemented include scatterometer, synthetic aperture radar, and altimetry; and plans to add new modes such as radiometry and bi-static GNSS signals are being formulated. This development is aimed at enhancing the radar remote sensing capabilities for airborne and spaceborne applications in support of Earth Science and planetary exploration This paper describes the design of the radar and processor systems, explains the operational modes, and discusses preliminary measurements and future plans.

  15. Amniotic Band Syndrome, Perinatal Hospice, and Palliative Care versus Active Management

    Directory of Open Access Journals (Sweden)

    Shadi Rezai

    2016-01-01

    Full Text Available Introduction. Amniotic band syndrome and sequence are a relatively rare condition in which congenital anomalies occur as a result of the adherence and entrapment of fetal parts with coarse fibrous bands of the amniotic membrane. A large percentage of reported cases have an atypical gestational history. The frequency of this obstetric complication is not affected by fetal gender, genetic abnormality, or prenatal infection. Case. A 21-year-old, G1P0 female parturient at 18 weeks and 5 days with a single intrauterine gestation during a routine ultrasound evaluation was noted to have amniotic band sequence. The pregnancy was subsequently complicated by preterm premature rupture of membranes with oligohydramnios, resulting in a surviving neonate scheduled for rehabilitative treatment. Conclusion. Amniotic band syndrome is an uncommon congenital anomaly resulting in multiple disfiguring and disabling manifestations. Several theories are proposed with most involving early rupture of the amnion and entanglement of fetal parts by amniotic bands. This syndrome can be manifested by development of multiple malformations, with the majority of the defects being limb abnormalities of a disorganized nature, as in the case we present. In the absence of a clear etiology of consequential congenital abnormalities, obstetric management guidelines should use shared decision models to focus on the quality of life for the offspring.

  16. Band-notched spiral antenna

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Jae; Chang, John

    2018-03-13

    A band-notched spiral antenna having one or more spiral arms extending from a radially inner end to a radially outer end for transmitting or receiving electromagnetic radiation over a frequency range, and one or more resonance structures positioned adjacent one or more segments of the spiral arm associated with a notch frequency band or bands of the frequency range so as to resonate and suppress the transmission or reception of electromagnetic radiation over said notch frequency band or bands.

  17. A randomised, double-blind study in adults with major depressive disorder with an inadequate response to a single course of selective serotonin reuptake inhibitor or serotonin-noradrenaline reuptake inhibitor treatment switched to vortioxetine or agomelatine.

    Science.gov (United States)

    Montgomery, Stuart A; Nielsen, Rebecca Z; Poulsen, Lis H; Häggström, Lars

    2014-09-01

    This randomised, double-blind, 12-week study compared efficacy and tolerability of flexible-dose treatment with vortioxetine(10-20 mg/day) versus agomelatine (25-50 mg/day) in major depressive disorder patients with inadequate response to selective serotonin reuptake inhibitor (SSRI)/serotonin-noradrenaline reuptake inhibitor (SNRI) monotherapy. Patients were switched directly from SSRI/SNRI to vortioxetine or agomelatine. Primary endpoint was change from baseline to week 8 in the Montgomery-Åsberg Depression Rating Scale (MADRS) total score analysed by mixed model for repeated measurements, using a noninferiority test followed by a superiority test. Secondary endpoints included response and remission rates, anxiety symptoms(Hamilton Anxiety Rating Scale), Clinical Global Impression, overall functioning (Sheehan Disability Scale), health-related quality of life(EuroQol 5 Dimensions), productivity (work limitation questionnaire) and family functioning (Depression and Family Functioning Scale). Primary endpoint noninferiority was established and vortioxetine (n = 252) was superior to agomelatine (n = 241) by 2.2 MADRS points (pDepression and Family Functioning Scale at weeks 8 and 12. Fewer patients withdrew because of adverse events with vortioxetine (5.9% vs 9.5%). Adverse events (incidence ≥5%) were nausea, headache, dizziness and somnolence. Vortioxetine was noninferior and significantly superior to agomelatine in major depressive disorder patients with previous inadequate response to a single course of SSRI/SNRI monotherapy. Vortioxetine was safe and well tolerated.

  18. Theoretical band alignment in an intermediate band chalcopyrite based material

    Science.gov (United States)

    Castellanos Águila, J. E.; Palacios, P.; Conesa, J. C.; Arriaga, J.; Wahnón, P.

    2017-12-01

    Band alignment is key to enhance the performance of heterojunction for chalcopyrite thin film solar cells. In this paper we report ab initio calculations of the electronic structures of CuGaS2:Cr with various Cr compositions, CuAlSe2 and ZnSe and the band alignment between their interfaces. We use density functional theory and the more accurate self-consistent GW scheme to obtain improved bulk band-gaps and band offsets. Band alignments of the interfacial region for CuGaS2:Cr/CuAlSe2 and CuGaS2:Cr/ZnSe systems were aligned with respect of an average electrostatic potential. Our results are in good agreement with experimental values for the bulk band-gaps. These theoretical band alignments show a characteristic staggered band alignment for the design of heterojunction devices in photovoltaic applications.

  19. Geochemistry of some banded iron-formations of the archean ...

    Indian Academy of Sciences (India)

    Banded iron-formations (BIF) form an important part of the Archean supracrustal belts of the. Jharkhand–Orissa region, India. Major, trace and REE chemistry of the banded iron-formation of the Gandhamardan, Deo Nala, Gorumahisani and Noamundi sections of the Jharkhand–Orissa region are utilized to explore the ...

  20. Geochemistry of some banded iron-formations of the archean ...

    Indian Academy of Sciences (India)

    Banded iron-formations (BIF) form an important part of the Archean supracrustal belts of the Jharkhand–Orissa region, India. Major, trace and REE chemistry of the banded iron-formation of the Gandhamardan, Deo Nala, Gorumahisani and Noamundi sections of the Jharkhand–Orissa region are utilized to explore the ...

  1. Quantum electrodynamics near a photonic band-gap

    Science.gov (United States)

    Liu, Yanbing; Houck, Andrew

    Quantum electrodynamics predicts the localization of light around an atom in photonic band-gap (PBG) medium or photonic crystal. Here we report the first experimental realization of the strong coupling between a single artificial atom and an one dimensional PBG medium using superconducting circuits. In the photonic transport measurement, we observe an anomalous Lamb shift and a large band-edge avoided crossing when the artificial atom frequency is tuned across the band-edge. The persistent peak within the band-gap indicates the single photon bound state. Furthermore, we study the resonance fluorescence of this bound state, again demonstrating the breakdown of the Born-Markov approximation near the band-edge. This novel architecture can be directly generalized to study many-body quantum electrodynamics and to construct more complicated spin chain models.

  2. Investigation of Double-Band Electrophoretic Pattern of ITS-rDNA Region in Iranian Isolates of Leishmania Tropica

    Directory of Open Access Journals (Sweden)

    MA Ghatee

    2013-06-01

    Full Text Available Background: Leishmania tropica is a genetically divergent species. Amplification of entire internal tran­scribed spacer (ITS region of L. tropica isolates obtained from Bam district, one of the well known focus of anthroponotic cutaneous leishmaniasis ACL( in Iran, revealed a double-band pat­tern in agarose gel electrophoresis. This study explains how this pattern occurs.Methods: Twenty seven L. tropica smear preparations were collected from Bam district, south east Iran, and eight L. major and one L. infantum smear preparations were gathered from Shiraz, south west Iran. Furthermore one L. major and one L. infantum cultured standard strains were tested using entire ITS-PCR to survey their electrophoretic pattern. The ITS sequences of L. tropica, L. major, and L. infantum already deposited in GenBank were analyzed. Analysis of GenBank sequences of L. tropica revealed two groups of sequences based on length size, one group having a 100 bp gap. Therefore, a new re­verse primer namely LITS-MG was designed to exclude this gap in PCR products.Results: Whole ITS fragment amplification resulted in a double-band pattern in all L. tropica cases, while a sharp single band was observed for L. infantum and L. major isolates. This result was correspond­ing to the result obtained from in silico analysis of GenBank sequences. Use of LITS-MG primer was expectedly resulted in a single band including ITS1, 5.8s and partial ITS2 product for L. tropica which is appropriate for following molecular studies such as sequencing or restriction analysis.Conclusion: Sequences analysis of GenBank L. tropica sequences and following practical laboratory tests revealed at least two alleles in L. tropica which were confirmed in Bam isolates. This especial double-band pattern is because of a 100 bp fragment difference within ITS-rDNA alleles

  3. Isolated olecranon fractures in children affected by osteogenesis imperfecta type I treated with single screw or tension band wiring system: Outcomes and pitfalls in relation to bone mineral density.

    Science.gov (United States)

    Persiani, Pietro; Ranaldi, Filippo M; Graci, Jole; De Cristo, Claudia; Zambrano, Anna; D'Eufemia, Patrizia; Martini, Lorena; Villani, Ciro

    2017-05-01

    The purpose of this study is to compare the results of 2 techniques, tension band wiring (TBW) and fixation with screws, in olecranon fractures in children affected with osteogenesis imperfecta (OI) type I. Between 2010 and 2014, 21 olecranon fractures in 18 children with OI (average age: 12 years old) were treated surgically. Ten patients were treated with the screw fixation and 11 with TBW. A total of 65% of olecranon fractures occurred as a result of a spontaneous avulsion of the olecranon during the contraction of the triceps muscle. The average follow-up was 36 months. Among the children treated with 1 screw, 5 patients needed a surgical revision with TBW due to a mobilization of the screw. In this group, the satisfactory results were 50%. In patients treated with TBW, the satisfactory results were 100% of the cases. The average Z-score, the last one recorded in the patients before the trauma, was -2.53 in patients treated with screw fixation and -2.04 in those treated with TBW. TBW represents the safest surgical treatment for patients suffering from OI type I, as it helps to prevent the rigidity of the elbow through an earlier recovery of the range of motion, and there was no loosening of the implant. In analyzing the average Z-score before any fracture, the fixation with screws has an increased risk of failure in combination with low bone mineral density.

  4. Ku-Band Data-Communication Adapter

    Science.gov (United States)

    Schadelbauer, Steve

    1995-01-01

    Data-communication adapter circuit on single printed-circuit board serves as general-purpose interface between personal computer and satellite communication system. Designed as direct interface with Ku-band data-communication system for payloads on space shuttle, also used with any radio-frequency transmission systems. Readily installed in almost any personal computer via widely used Industry Standard Architecture (ISA) bus.

  5. Semiconductors bonds and bands

    CERN Document Server

    Ferry, David K

    2013-01-01

    As we settle into this second decade of the twenty-first century, it is evident that the advances in micro-electronics have truly revolutionized our day-to-day lifestyle. The technology is built upon semiconductors, materials in which the band gap has been engineered for special values suitable to the particular application. This book, written specifically for a one semester course for graduate students, provides a thorough understanding of the key solid state physics of semiconductors. It describes how quantum mechanics gives semiconductors unique properties that enabled the micro-electronics revolution, and sustain the ever-growing importance of this revolution.

  6. Microstrip microwave band gap structures

    Indian Academy of Sciences (India)

    Microwave band gap structures exhibit certain stop band characteristics based on the periodicity, impedance contrast and effective refractive index contrast. These structures though formed in one-, two- and three-dimensional periodicity, are huge in size. In this paper, microstrip-based microwave band gap structures are ...

  7. A compact ultra wideband antenna with WiMax band rejection for energy scavenging

    International Nuclear Information System (INIS)

    Jalil, Y E; Chakrabarty, C K; Kasi, B

    2013-01-01

    Radio Frequency (RF) energy harvesting has been rapidly advancing as a promising alternative to existing energy scavenging system. A well designed broadband antenna such as ultra-wideband (UWB) antenna can be used as one of the major components in an RF energy scavenging system. This paper presents a compact UWB antenna showing good impedance matching over a bandwidth of 2.8 to 11 GHz, suiTable for broadband RF energy scavenging. Nevertheless, the antenna usage in wireless communication has a limitation due to the problem of interference between UWB system and other narrowband systems. Thus, the proposed antenna is successfully designed with a single band-notched at the targeted WiMAX operating band of 3.3 to 3.6 GHz.

  8. Morphologies of omega band auroras

    Science.gov (United States)

    Sato, Natsuo; Yukimatu, Akira Sessai; Tanaka, Yoshimasa; Hori, Tomoaki

    2017-08-01

    We examined the morphological signatures of 315 omega band aurora events observed using the Time History of Events and Macroscale Interactions during Substorm ground-based all-sky imager network over a period of 8 years. We find that omega bands can be classified into the following three subtypes: (1) classical (O-type) omega bands, (2) torch or tongue (T-type) omega bands, and (3) combinations of classical and torch or tongue (O/T-type) omega bands. The statistical results show that T-type bands occur the most frequently (45%), followed by O/T-type bands (35%) and O-type bands (18%). We also examined the morphologies of the omega bands during their formation, from the growth period to the declining period through the maximum period. Interestingly, the omega bands are not stable, but rather exhibit dynamic changes in shape, intensity, and motion. They grow from small-scale bumps (seeds) at the poleward boundary of preexisting east-west-aligned auroras, rather than via the rotation or shear motion of preexisting east-west-aligned auroras, and do not exhibit any shear motion during the periods of auroral activity growth. Furthermore, the auroral luminosity is observed to increase during the declining period, and the total time from the start of the growth period to the end of the declining period is found to be about 20 min. Such dynamical signatures may be important in determining the mechanism responsible for omega band formation.

  9. Adverse effects of intravenous acetazolamide administration for evaluation of cerebrovascular reactivity using brain perfusion single-photon emission computed tomography in patients with major cerebral artery steno-occlusive diseases

    International Nuclear Information System (INIS)

    Saito, Hideo; Ogasawara, Kuniaki; Suzuki, Taro; Kuroda, Hiroki; Kobayashi, Masakazu; Yoshida, Kenji; Kubo, Yoshitaka; Ogawa, Akira

    2011-01-01

    Adverse effects of intravenous acetazolamide administration for evaluation of cerebrovascular reactivity using brain perfusion single-photon emission computed tomography (SPECT) were prospectively investigated in 100 patients with major cerebral artery, atherosclerotic, and steno-occlusive diseases. All patients underwent two SPECT studies (with and without acetazolamide challenge) at an interval of 2 or 3 days, received a questionnaire immediately after each SPECT study, and returned the answered questionnaire within 7 days after the study. None of the 100 patients studied experienced any symptoms during the SPECT study without acetazolamide challenge. Sixty-three patients (63%) developed symptoms during the SPECT study with acetazolamide challenge, such as headache, nausea, dizziness, tinnitus, numbness of the extremities, motor weakness of the extremities, and general malaise 1-3 hours (mean 1.6 hours) after administration of acetazolamide, and these symptoms lasted for 0.5-72 hours (mean 7.9 hours). Multivariate statistical analysis revealed that younger age (95% confidence interval [CI] 0.896-0.980, p=0.0047) and female sex (95% CI 1.178-16.129, p=0.0274) were significantly associated with development of symptoms with acetazolamide challenge. The incidences of the development of symptoms with acetazolamide challenge were 91% (21/23) and 41% (12/29) in subgroups of women <70 years and men ≥70 years, respectively. Patients should be informed of such adverse effects of intravenous acetazolamide administration prior to the acetazolamide challenge test for evaluation of cerebrovascular reactivity. (author)

  10. Dose banding as an alternative to body surface area-based dosing of chemotherapeutic agents

    NARCIS (Netherlands)

    E. Chatelut (Etienne); M.L. White-Koning (M.); A.H.J. Mathijssen (Ron); F. Puisset (F.); S.D. Baker (Sharyn); A. Sparreboom (Alex)

    2012-01-01

    textabstractBackground: Dose banding is a recently suggested dosing method that uses predefined ranges (bands) of body surface area (BSA) to calculate each patients dose by using a single BSA-value per band. Thus, drugs with sufficient long-term stability can be prepared in advance. The main

  11. Strongly Correlated Electron Systems in The Half Filled Band of The ...

    African Journals Online (AJOL)

    Strong correlation of interacting electrons has been widely studied under the single band Hubbard model with the aid of several techniques. These numerous studies have been carried out at different band filling. In this work, the ground state properties in the half filled band in one dimension are studied employing a ...

  12. Understanding band gaps of solids in generalized Kohn–Sham theory

    Science.gov (United States)

    Perdew, John P.; Yang, Weitao; Burke, Kieron; Yang, Zenghui; Gross, Eberhard K. U.; Scheffler, Matthias; Scuseria, Gustavo E.; Henderson, Thomas M.; Zhang, Igor Ying; Ruzsinszky, Adrienn; Peng, Haowei; Sun, Jianwei; Trushin, Egor; Görling, Andreas

    2017-01-01

    The fundamental energy gap of a periodic solid distinguishes insulators from metals and characterizes low-energy single-electron excitations. However, the gap in the band structure of the exact multiplicative Kohn–Sham (KS) potential substantially underestimates the fundamental gap, a major limitation of KS density-functional theory. Here, we give a simple proof of a theorem: In generalized KS theory (GKS), the band gap of an extended system equals the fundamental gap for the approximate functional if the GKS potential operator is continuous and the density change is delocalized when an electron or hole is added. Our theorem explains how GKS band gaps from metageneralized gradient approximations (meta-GGAs) and hybrid functionals can be more realistic than those from GGAs or even from the exact KS potential. The theorem also follows from earlier work. The band edges in the GKS one-electron spectrum are also related to measurable energies. A linear chain of hydrogen molecules, solid aluminum arsenide, and solid argon provide numerical illustrations. PMID:28265085

  13. Understanding band gaps of solids in generalized Kohn-Sham theory.

    Science.gov (United States)

    Perdew, John P; Yang, Weitao; Burke, Kieron; Yang, Zenghui; Gross, Eberhard K U; Scheffler, Matthias; Scuseria, Gustavo E; Henderson, Thomas M; Zhang, Igor Ying; Ruzsinszky, Adrienn; Peng, Haowei; Sun, Jianwei; Trushin, Egor; Görling, Andreas

    2017-03-14

    The fundamental energy gap of a periodic solid distinguishes insulators from metals and characterizes low-energy single-electron excitations. However, the gap in the band structure of the exact multiplicative Kohn-Sham (KS) potential substantially underestimates the fundamental gap, a major limitation of KS density-functional theory. Here, we give a simple proof of a theorem: In generalized KS theory (GKS), the band gap of an extended system equals the fundamental gap for the approximate functional if the GKS potential operator is continuous and the density change is delocalized when an electron or hole is added. Our theorem explains how GKS band gaps from metageneralized gradient approximations (meta-GGAs) and hybrid functionals can be more realistic than those from GGAs or even from the exact KS potential. The theorem also follows from earlier work. The band edges in the GKS one-electron spectrum are also related to measurable energies. A linear chain of hydrogen molecules, solid aluminum arsenide, and solid argon provide numerical illustrations.

  14. Wide Band Artificial Pulsar

    Science.gov (United States)

    Parsons, Zackary

    2017-01-01

    The Wide Band Artificial Pulsar (WBAP) is an instrument verification device designed and built by the National Radio Astronomy Observatory (NRAO) in Green Bank, West Virgina. The site currently operates the Green Bank Ultimate Pulsar Processing Instrument (GUPPI) and the Versatile Green Bank Astronomical Spectrometer (VEGAS) digital backends for their radio telescopes. The commissioning and continued support for these sophisticated backends has demonstrated a need for a device capable of producing an accurate artificial pulsar signal. The WBAP is designed to provide a very close approximation to an actual pulsar signal. This presentation is intended to provide an overview of the current hardware and software implementations and to also share the current results from testing using the WBAP.

  15. Screening of highly informative and representative microsatellite markers for genotyping of major cultivated cotton varieties.

    Science.gov (United States)

    Kuang, M; Yang, W H; Wang, F; Xu, H X; Wang, Y Q; Zhou, D Y; Fang, D; Ma, L; Feng, X A

    2014-11-27

    We screened and assessed published cotton simple sequence repeat (SSR) primers to establish a set of core SSR markers suitable for cotton major cultivars in China and analyzed genetic diversity based on the core marker set. Using a stepwise screening strategy, 12 leading cultivars for preliminary screening and 96 cultivars for rescreening were evaluated. A total of 184 polymorphic SSR markers were initially screened from 3299 candidates, and a core set of 52 SSR markers with wide genome coverage (2 markers per chromosome) was obtained. Among 96 major cultivars, 273 amplification genotypes were generated using the core marker set. Polymorphism information content values ranged from 0.28-0.83, with an average value of 0.56. The core SSR marker set detected on denaturing polyacrylamide gel electrophoresis indicated that the band genotype was either a single or double band on conventional cultivars, while most were double bands (65.4%). Among 56 hybrids, the average heterozygosis rate was 35.8%, ranging from 7.1-55.4%. Eighteen of 96 cultivars had distinct band genotypes. The genetic diversity analyzed using the of NTSYS-pc V2.10 software indicated that the Yangtze River valley cotton region had the highest polymorphic level, followed by Xinjiang and then the Yellow River valley. The genetic basis of conventional cultivars was narrower than that of hybrids. The core marker set can be used for fingerprint construction, variety identification, and purity tests of major cotton cultivars in China.

  16. Prognostic value of myocardial perfusion single photon emission computed tomography for major adverse cardiac cerebrovascular and renal events in patients with chronic kidney disease: results from first year of follow-up of the Gunma-CKD SPECT multicenter study

    International Nuclear Information System (INIS)

    Kasama, Shu; Toyama, Takuji; Sato, Makito; Sano, Hirokazu; Ueda, Tetsuya; Sasaki, Toyoshi; Nakahara, Takehiro; Kurabayashi, Masahiko; Higuchi, Tetsuya; Tsushima, Yoshito

    2016-01-01

    Patients with chronic kidney disease (CKD) have an increased risk of adverse cardio-cerebrovascular events. We examined whether stress myocardial perfusion single photon emission computed tomography (SPECT) provides reliable prognostic markers for these patients. In this multicenter, prospective cohort trial from the Gunma-CKD SPECT study protocol, patients with CKD [estimated glomerular filtration rate (eGFR) < 60 min/ml per 1.73 m 2 ] undergoing stress 99m Tc-tetrofosmin SPECT for suspected or possible ischemic heart disease were initially followed for 1 year, with the following study endpoints: primary, the occurrence of cardiac deaths (CDs), and secondary, major adverse cardiac, cerebrovascular, and renal events (MACCREs). The summed stress score (SSS), summed rest score, and summed difference score (SDS) were estimated with the standard 17-segment, 5-point scoring model. Left ventricular end-diastolic volume, end-systolic volume (ESV), and ejection fraction were measured using electrocardiogram-gated SPECT. During the first year of follow-up, 69 of 299 patients experienced MACCREs (CD, n = 7; non-fatal myocardial infarction, n = 3; hospitalization for heart failure, n = 13; cerebrovascular accident, n = 1; need for revascularization, n = 38; and renal failure, i.e., hemodialysis initiation, n = 7). ESV and SSS were associated with CDs (p < 0.05), and eGFR and SDS were associated with MACCREs (p < 0.05), in multivariate logistic analysis. Patients with high ESV and high SSS had a significantly higher CD rate during the first year than the other CKD patient subgroups (p < 0.05). Patients with low eGFR and high SDS had a significantly higher MACCRE rate than the other subgroups (p < 0.05). Myocardial perfusion SPECT can provide reliable prognostic markers for patients with CKD. (orig.)

  17. Female sexual dysfunction in patients with major depressive disorder (MDD) treated with selective serotonin reuptake inhibitor (SSRI) and its association with serotonin 2A-1438 G/A single nucleotide polymorphisms.

    Science.gov (United States)

    Masiran, Ruziana; Sidi, Hatta; Mohamed, Zahurin; Mohd Nazree, Nur Elia; Nik Jaafar, Nik Ruzyanei; Midin, Marhani; Das, Srijit; Mohamed Saini, Suriati

    2014-04-01

    Selective serotonin reuptake inhibitors (SSRIs) are known for their sexual side effects. Different SSRIs may affect different areas of sexual function at different rates. The study aimed to determine the prevalence of female sexual dysfunction (FSD), its clinical correlates, and association with 5HT2A (rs6311) single nucleotide polymorphisms (SNPs) in patients with major depressive disorder (MDD) who were on SSRI therapy. This was a cross-sectional study on 95 female outpatients with MDD treated with SSRI. The patients were in remission as determined by Montgomery-Asberg Depression Rating Scale. Genomic DNA was isolated from buccal swabs and samples were processed using a real time polymerase chain reaction. The presence or absence of FSD as measured by the Malay Version of Female Sexual Function Index and 5HT2A-1438 G/A (rs6311) SNP. The overall prevalence of FSD was 32.6%. After controlling for age, number of children, education level, total monthly income, SSRI types, and SSRI dosing, being employed significantly enhanced FSD by 4.5 times (odds ratio [OR] = 4.51; 95% confidence interval [CI] 1.00, 20.30; P = 0.05). Those having marital problems were 6.7 times more likely to have FSD (OR = 6.67; 95% CI 1.57, 28.34). 5HT2A-1438 G/A (rs6311) SNP was not significantly associated with FSD. There was no significant association between FSD and the 5HT2A (rs6311) SNP in patients with MDD on SSRI therapy. Employment status and marital state were significantly associated with FSD among these patients. © 2014 International Society for Sexual Medicine.

  18. Prognostic value of myocardial perfusion single photon emission computed tomography for major adverse cardiac cerebrovascular and renal events in patients with chronic kidney disease: results from first year of follow-up of the Gunma-CKD SPECT multicenter study

    Energy Technology Data Exchange (ETDEWEB)

    Kasama, Shu [Gunma University Graduate School of Medicine, Department of Medicine and Biological Science (Cardiovascular Medicine), Maebashi, Gunma (Japan); Cardiovascular Hospital of Central Japan (Kitakanto Cardiovascular Hospital), Department of Cardiovascular Medicine, Gunma (Japan); Toyama, Takuji [Department of Cardiovascular Medicine, Gunma Prefectural Cardiovascular Center, Maebashi (Japan); Sato, Makito [Gunma University Graduate School of Medicine, Department of Medicine and Biological Science (Cardiovascular Medicine), Maebashi, Gunma (Japan); Tatebayashi Kosei Hospital, Department of Internal Medicine, Gunma (Japan); Sano, Hirokazu [Gunma University Graduate School of Medicine, Department of Medicine and Biological Science (Cardiovascular Medicine), Maebashi, Gunma (Japan); Isesaki Municipal Hospital, Department of Cardiovascular Medicine, Isesaki (Japan); Ueda, Tetsuya [Fujioka General Hospital, Division of Cardiology, Fujioka (Japan); Sasaki, Toyoshi [Takasaki General Medical Center, Division of Cardiology, Takasaki (Japan); Nakahara, Takehiro; Kurabayashi, Masahiko [Gunma University Graduate School of Medicine, Department of Medicine and Biological Science (Cardiovascular Medicine), Maebashi, Gunma (Japan); Higuchi, Tetsuya; Tsushima, Yoshito [Gunma University Graduate School of Medicine, Department of Diagnostic Radiology and Nuclear Medicine, Maebashi (Japan)

    2016-02-15

    Patients with chronic kidney disease (CKD) have an increased risk of adverse cardio-cerebrovascular events. We examined whether stress myocardial perfusion single photon emission computed tomography (SPECT) provides reliable prognostic markers for these patients. In this multicenter, prospective cohort trial from the Gunma-CKD SPECT study protocol, patients with CKD [estimated glomerular filtration rate (eGFR) < 60 min/ml per 1.73 m{sup 2}] undergoing stress {sup 99m}Tc-tetrofosmin SPECT for suspected or possible ischemic heart disease were initially followed for 1 year, with the following study endpoints: primary, the occurrence of cardiac deaths (CDs), and secondary, major adverse cardiac, cerebrovascular, and renal events (MACCREs). The summed stress score (SSS), summed rest score, and summed difference score (SDS) were estimated with the standard 17-segment, 5-point scoring model. Left ventricular end-diastolic volume, end-systolic volume (ESV), and ejection fraction were measured using electrocardiogram-gated SPECT. During the first year of follow-up, 69 of 299 patients experienced MACCREs (CD, n = 7; non-fatal myocardial infarction, n = 3; hospitalization for heart failure, n = 13; cerebrovascular accident, n = 1; need for revascularization, n = 38; and renal failure, i.e., hemodialysis initiation, n = 7). ESV and SSS were associated with CDs (p < 0.05), and eGFR and SDS were associated with MACCREs (p < 0.05), in multivariate logistic analysis. Patients with high ESV and high SSS had a significantly higher CD rate during the first year than the other CKD patient subgroups (p < 0.05). Patients with low eGFR and high SDS had a significantly higher MACCRE rate than the other subgroups (p < 0.05). Myocardial perfusion SPECT can provide reliable prognostic markers for patients with CKD. (orig.)

  19. Prognostic value of myocardial perfusion single photon emission computed tomography for major adverse cardiac cerebrovascular and renal events in patients with chronic kidney disease: results from first year of follow-up of the Gunma-CKD SPECT multicenter study.

    Science.gov (United States)

    Kasama, Shu; Toyama, Takuji; Sato, Makito; Sano, Hirokazu; Ueda, Tetsuya; Sasaki, Toyoshi; Nakahara, Takehiro; Higuchi, Tetsuya; Tsushima, Yoshito; Kurabayashi, Masahiko

    2016-02-01

    Patients with chronic kidney disease (CKD) have an increased risk of adverse cardio-cerebrovascular events. We examined whether stress myocardial perfusion single photon emission computed tomography (SPECT) provides reliable prognostic markers for these patients. In this multicenter, prospective cohort trial from the Gunma-CKD SPECT study protocol, patients with CKD [estimated glomerular filtration rate (eGFR) disease were initially followed for 1 year, with the following study endpoints: primary, the occurrence of cardiac deaths (CDs), and secondary, major adverse cardiac, cerebrovascular, and renal events (MACCREs). The summed stress score (SSS), summed rest score, and summed difference score (SDS) were estimated with the standard 17-segment, 5-point scoring model. Left ventricular end-diastolic volume, end-systolic volume (ESV), and ejection fraction were measured using electrocardiogram-gated SPECT. During the first year of follow-up, 69 of 299 patients experienced MACCREs (CD, n = 7; non-fatal myocardial infarction, n = 3; hospitalization for heart failure, n = 13; cerebrovascular accident, n = 1; need for revascularization, n = 38; and renal failure, i.e., hemodialysis initiation, n = 7). ESV and SSS were associated with CDs (p < 0.05), and eGFR and SDS were associated with MACCREs (p < 0.05), in multivariate logistic analysis. Patients with high ESV and high SSS had a significantly higher CD rate during the first year than the other CKD patient subgroups (p < 0.05). Patients with low eGFR and high SDS had a significantly higher MACCRE rate than the other subgroups (p < 0.05). Myocardial perfusion SPECT can provide reliable prognostic markers for patients with CKD.

  20. Electron band theory 1952-1962

    International Nuclear Information System (INIS)

    Lomer, W.M.

    1980-01-01

    Work undertaken by the Theoretical Physics Division between 1952 and 1965 to obtain an understanding of electrons in metals, with uranium and the actinides and the structurally-important transition metals as the main targets is examined. A main result of that period was a conviction that the majority of the physical properties of all metals, except the 4f rare-earth series and the actinides beyond uranium, were dominated by band effects which could be described well enough for most purposes by simple one-electron calculations with simple self-consistent fields. The period from 1960 on showed increasingly clearly the necessity of incorporating relativistic spin-orbit coupling terms in the heavy metals, and some 'local exchange field' correction to the fields close to nuclei. The problems of the non-local interaction of spins - highly important for alloy theory and for antiferromagnetic instability -required the evolution of computers large enough to produce wave-functions at all wave-vectors for all bands so that the susceptibility at arbitrary wave-vector could be computed. This work has not proved to be very illuminating so far, and much interest again focusses today on heuristic arguments that give qualitative descriptions of band structures, such as canonical d-bands to account for crystal structure. (UK)

  1. A 38-year Summary of Raptor Banding at Hawk Ridge, Duluth, Minnesota, USA

    Science.gov (United States)

    Consistent banding of raptors at Hawk Ridge was initiated in 1972 and has continued for 38 years to the present. A total of 99,505 raptors or 2,619 per year have been banded at Hawk Ridge including 23 different species. The majority of birds banded were Sharp-shinned Hawks (Acci...

  2. Dual-band infrared camera

    Science.gov (United States)

    Vogel, H.; Schlemmer, H.

    2005-10-01

    Every year, numerous accidents happen on European roads due to bad visibility (fog, night, heavy rain). Similarly, the dramatic aviation accidents of year 2001 in Milan and Zurich have reminded us that aviation safety is equally affected by reduced visibility. A dual-band thermal imager was developed in order to raise human situation awareness under conditions of reduced visibility especially in the automotive and aeronautical context but also for all transportation or surveillance tasks. The chosen wavelength bands are the Short Wave Infrared SWIR and the Long Wave Infrared LWIR band which are less obscured by reduced visibility conditions than the visible band. Furthermore, our field tests clearly show that the two different spectral bands very often contain complementary information. Pyramidal fusion is used to integrate complementary and redundant features of the multi-spectral images into a fused image which can be displayed on a monitor to provide more and better information for the driver or pilot.

  3. Radiating Elements for Shared Aperture Tx/Rx Phased Arrays at K/Ka Band

    KAUST Repository

    Sandhu, Ali Imran

    2016-04-11

    A dual band, Tx/Rx, self-diplexing phased array is presented. The antenna has been designed to cover Tx/Rx satellite communications at K/Ka band with a frequency ratio 1.5:1. To obtain dual band operations with a single radiating surface, a novel dual band radiator is adopted and placed in a configuration in which dual band and single band elements are interleaved. The proposed configuration reduces the number of radiating elements required by other solutions while avoiding the insurgence of grating lobes. The tightly packed arrangement of the elements poses many integration issues, which are solved with a novel integration technique. The array elements are optimized to scan the beam in excess of ° in both bands. A subarray with 49 Rx elements and 105 Tx elements was built and measured confirming the results obtained in simulations.

  4. Band-notched ultrawide band antenna loaded with ferrite slab

    Science.gov (United States)

    Wang, Hao; Zong, Weihua; Sun, Nian X.; Lin, Hwaider; Li, Shandong

    2017-05-01

    In this paper, a novel technique to design a band-notched UWB antenna by using Yttrium Iron Garnet (YIG) ferrite is proposed. A printed slot UWB antenna with size of 21mm×26 mm×0.8 mm is adopted as a basic antenna. A piece of ferrite slab with size of 5 mm×10 mm×2 mm is attached on the feeding layer of the antenna to achieve band-notched characteristics. The measured -10 dB bandwidth of the antenna without ferrite slab is 2.91-10.98 GHz. With loading of ferrite slab, the bandwidth turns to 2.73-5.12 and 5.87-10.78 GHz. A band notch of 5.12- 5.87 GHz is achieved to filter WLAN 5 GHz (5.15-5.825 GHz) band. The proposed technique has virtue of easy fabrication and keeping antenna miniaturization.

  5. Band-to-Band Tunneling Transistors: Scalability and Circuit Performance

    Science.gov (United States)

    2013-05-01

    55* MEDICI ...3.2.1 Tunneling Theory 3.3 Simulation Methods 3.3.1 MEDICI 3.3.2 Sentaurus Local Tunneling 3.3.3 Sentaurus Nonlocal Tunneling 3.4 Sentaurus...tunneling current. 3.3.1 MEDICI MEDICI is a one and two-dimensional simulator created by Synopsys, Inc. [18]. It contains a band-to-band

  6. Single vs. dual color fire detection systems: operational tradeoffs

    Science.gov (United States)

    Danino, Meir; Danan, Yossef; Sinvani, Moshe

    2017-10-01

    In attempt to supply a reasonable fire plume detection, multinational cooperation with significant capital is invested in the development of two major Infra-Red (IR) based fire detection alternatives, single-color IR (SCIR) and dual-color IR (DCIR). False alarm rate was expected to be high not only as a result of real heat sources but mainly due to the IR natural clutter especially solar reflections clutter. SCIR uses state-of-the-art technology and sophisticated algorithms to filter out threats from clutter. On the other hand, DCIR are aiming at using additional spectral band measurements (acting as a guard), to allow the implementation of a simpler and more robust approach for performing the same task. In this paper we present the basics of SCIR & DCIR architecture and the main differences between them. In addition, we will present the results from a thorough study conducted for the purpose of learning about the added value of the additional data available from the second spectral band. Here we consider the two CO2 bands of 4-5 micron and of 2.5-3 micron band as well as off peak band (guard). The findings of this study refer also to Missile warning systems (MWS) efficacy, in terms of operational value. We also present a new approach for tunable filter to such sensor.

  7. Enhanced dual-band infrared absorption in a Fabry-Perot cavity with subwavelength metallic grating.

    Science.gov (United States)

    Kang, Guoguo; Vartiainen, Ismo; Bai, Benfeng; Turunen, Jari

    2011-01-17

    The performance of infrared (IR) dual-band detector can be substantially improved by simultaneously increasing IR absorptions for both sensor bands. Currently available methods only provide absorption enhancement for single spectral band, but not for the dual-band. The Fabry-Perot (FP) cavity generates a series of resonances in multispectral bands. With this flexibility, we introduced a novel type of dual-band detector structure containing a multilayer FP cavity with two absorbing layers and a subwavelength-period grating mirror, which is capable of simultaneously enhancing the middle wave infrared (MWIR) and the long wave infrared (LWIR) detection. Compared with the bare-absorption-layer detector (common dual-band detector), the optimized FP cavity can provide about 13 times and 17 times absorption enhancement in LWIR and MWIR bands respectively.

  8. A Novel Tunable Triple-Band Left-Handed Metamaterial

    Directory of Open Access Journals (Sweden)

    Si Li

    2017-01-01

    Full Text Available A novel tunable triple-band left-handed metamaterial (LHM composed of a single-loop resonator (SLR and a variable capacitor-loaded short wire pair (CL-SWP printed on both sides of a substrate is presented in this paper. The CL-SWP-based metamaterial (MTM is a novel single-sided LHM. It is theoretically analyzed capable of extracting tunable negative permeability and a wide-band negative permittivity. We ran simulations for the CL-SWP-based MTM, the SLR-based MTM, and the proposed LHM. Together with the measured results, it is identified that this novel LHM exhibits a tunable triple-band left-handed (LH property. With the increase of the loaded capacitance, one LH band is relatively stable, while the other two are moving towards lower frequencies with their bandwidth getting wider and narrower, respectively. The surface current density distributions indicate that the first LH band is mainly decided by the SLR, one of the rest 2 LH bands is mainly decided by the CL-SWP, and the other one is decided by the SLR and CL-SWP together.

  9. Theory of Fermi Liquid with Flat Bands

    Science.gov (United States)

    Khodel, V. A.

    2018-04-01

    A self-consistent theory of Fermi systems hosting flat bands is developed. Compared with an original model of fermion condensation, its key point consists in proper accounting for mixing between condensate and non-condensate degrees of freedom that leads to formation of a non-BCS gap Υ (p) in the single-particle spectrum. The results obtained explain: (1) the two-gap structure of spectra of single-particle excitations of electron systems of copper oxides, revealed in ARPES studies, (2) the role of violation of the topological stability of the Landau state in the arrangement of the T-x phase diagram of this family of high-T_c superconductors, (3) the topological nature of a metal-insulator transition, discovered in homogeneous two-dimensional low-density electron liquid of MOSFETs more than 20 years ago.

  10. Theory of Fermi Liquid with Flat Bands

    Science.gov (United States)

    Khodel, V. A.

    2017-11-01

    A self-consistent theory of Fermi systems hosting flat bands is developed. Compared with an original model of fermion condensation, its key point consists in proper accounting for mixing between condensate and non-condensate degrees of freedom that leads to formation of a non-BCS gap Υ (p) in the single-particle spectrum. The results obtained explain: (1) the two-gap structure of spectra of single-particle excitations of electron systems of copper oxides, revealed in ARPES studies, (2) the role of violation of the topological stability of the Landau state in the arrangement of the T-x phase diagram of this family of high-T_c superconductors, (3) the topological nature of a metal-insulator transition, discovered in homogeneous two-dimensional low-density electron liquid of MOSFETs more than 20 years ago.

  11. Intensity formulas for triplet bands

    Science.gov (United States)

    Budo, A.

    1982-01-01

    Previous work in this area is surveyed and the mathematics involved in determining the quantitative intensity measurements in triplet bands is presented. Explicit expressions for the intensity distribution in the branches of the 3 Sigma-3 Pi and 1 Sigma-3Pi bands valid for all values of the coupling constant Y of the 3 Pi terms are given. The intensity distribution calculated according to the formulas given is compared with measurements of PH, 3 Pi-3 Sigma. Good quantitative agreement is obtained.

  12. Emission bands of phosphorus and calculation of band structure of rare earth phosphides

    International Nuclear Information System (INIS)

    Al'perovich, G.I.; Gusatinskij, A.N.; Geguzin, I.I.; Blokhin, M.A.; Torbov, V.I.; Chukalin, V.I.; AN SSSR, Moscow. Inst. Novykh Khimicheskikh Problem)

    1977-01-01

    The method of x-ray emission spectroscopy has been used to investigate the electronic structure of monophosphides of rare-earth metals (REM). The fluorescence K bands of phosphorus have been obtained in LaP, PrP, SmP, GdP, TbP, DyP, HoP, ErP, TmP, YbP, and LuP and also the Lsub(2,3) bands of phosphorus in ErP, TmP, YbP, and LuP. Using the Green function technique involving the muffin-tin potential, the energy spectrum for ErP has been calculated in the single-electron approximation. The hystogram of electronic state distribution N(E) is compared with the experimental K and Lsub(2,3) bands of phosphorus in ErP. The agreement between the main details of N(E) and that of x-ray spectra allows to state that the model used provides a good description of the electron density distribution in crystals of REM monophosphides. In accordance with the character of the N(E) distribution the compounds under study are classified as semimetals or semiconductors with a very narrow forbidden band

  13. Analyzing Shear Band Formation with High Resolution X-ray

    Energy Technology Data Exchange (ETDEWEB)

    Pagan, Darren C.; Obstalecki, Mark; Park, Jun-Sang; Miller, Matthew P.

    2018-04-01

    Localization of crystallographic slip into shear bands during uniaxial compression of a copper single crystal is studied using very far-field high-energy diffraction microscopy (vff-HEDM). Diffracted intensity was collected in-situ as the crystal deformed using a unique mobile detector stage that provided access to multiple diffraction peaks with high-angular resolution. From the diffraction data, single crystal orientation pole figures (SCPFs) were generated and are used to track the evolution of the distribution of lattice orientation that develops as slip localizes. To aid the identification of 'signatures' of shear band formation and analyze the SCPF data, a model of slip-driven lattice reorientation within shear bands is introduced. Confidence is built in conclusions drawn from the SCPF data about the character of internal slip localization through comparisons with strain fields on the sample surface measured simultaneously using digital image correlation. From the diffraction data, we find that the active slip direction and slip plane are not directly aligned with the orientation of the shear bands that formed. In fact, by extracting the underlying slip system activity from the SCPF data, we show that intersecting shear bands measured on the surface of the sample arise from slip primarily on the same underlying single slip system. These new vff-HEDM results raise significant questions on the use of surface measurements for slip system activity estimation. (C) 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  14. Self-consistent, relativistic, ferromagnetic band structure of gadolinium

    International Nuclear Information System (INIS)

    Harmon, B.N.; Schirber, J.; Koelling, D.D.

    1977-01-01

    An initial self-consistent calculation of the ground state magnetic band structure of gadolinium is described. A linearized APW method was used which included all single particle relativistic effects except spin-orbit coupling. The spin polarized potential was obtained in the muffin-tin form using the local spin density approximation for exchange and correlation. The most striking and unorthodox aspect of the results is the position of the 4f spin-down ''bands'' which are required to float just on top of the Fermi level in order to obtain convergence. If the 4f states (l = 3 resonance) are removed from the occupied region of the conduction bands the magnetic moment is approximately .75 μ/sub B//atom; however, as the 4f spin-down states are allowed to find their own position they hybridize with the conduction bands at the Fermi level and the moment becomes smaller. Means of improving the calculation are discussed

  15. A Small UWB Antenna with Dual Band-Notched Characteristics

    Directory of Open Access Journals (Sweden)

    J. Xu

    2012-01-01

    Full Text Available A small novel ultrawideband (UWB antenna with dual band-notched functions is proposed. The dual band rejection is achieved by etching two C-shaped slots on the radiation patch with limited area. A single band-notched antenna is firstly presented, and then an optimized dual band-notched antenna is presented and analyzed. The measured VSWR shows that the proposed antenna could operate from 3.05 to 10.7 GHz with VSWR less than 2, except two stopbands at 3.38 to 3.82 GHz and 5.3 to 5.8 GHz for filtering the WiMAX and WLAN signals. Radiation patterns are simulated by HFSS and verified by CST, and quasiomnidirectional radiation patterns in the H-plane could be observed. Moreover, the proposed antenna has a very compact size and could be easily integrated into portable UWB devices.

  16. Noise Reduction using Frequency Sub-Band Adaptive Spectral Subtraction

    Science.gov (United States)

    Kozel, David

    2000-01-01

    A frequency sub-band based adaptive spectral subtraction algorithm is developed to remove noise from noise-corrupted speech signals. A single microphone is used to obtain both the noise-corrupted speech and the estimate of the statistics of the noise. The statistics of the noise are estimated during time frames that do not contain speech. These statistics are used to determine if future time frames contain speech. During speech time frames, the algorithm determines which frequency sub-bands contain useful speech information and which frequency sub-bands contain only noise. The frequency sub-bands, which contain only noise, are subtracted off at a larger proportion so the noise does not compete with the speech information. Simulation results are presented.

  17. V-band electronically reconfigurable metamaterial

    Science.gov (United States)

    Radisic, Vesna; Hester, Jimmy G.; Nguyen, Vinh N.; Caira, Nicholas W.; DiMarzio, Donald; Hilgeman, Theodore; Larouche, Stéphane; Kaneshiro, Eric; Gutierrez-Aitken, Augusto

    2017-04-01

    In this work, we report on a reconfigurable V-band metamaterial fabricated using an InP heterojunction bipolar transistor production process. As designed and fabricated, the implementation uses complementary split ring resonators (cSRRs) and Schottky diodes in both single unit cell and three unit cell monolithic microwave integrated circuits. Each unit cell has two diodes embedded within the gaps of the cSRRs. Reconfigurability is achieved by applying an external bias that turns the diodes on and off, which effectively controls the resonant property of the structure. In order to measure the metamaterial properties, the unit cells are fed and followed by transmission lines. Measured data show good agreement with simulations and demonstrate that the metamaterial structure exhibits resonance at around 65 GHz that can be switched on and off. The three-unit cell transmission line metamaterial shows a deeper resonance and a larger phase change than a single cell, as expected. These are the first reported reconfigurable metamaterials operating at the V-band using the InP high speed device fabrication process.

  18. Effect of photonic band gap on entanglement dynamics of qubits

    OpenAIRE

    Wu, Jing-Nuo; Hsieh, Wen-Feng; Cheng, Szu-Cheng

    2012-01-01

    We study how the environment of photonic band gap (PBG) materials affects entanglement dynamics of qubits. Entanglement between the single qubit and the PBG environment is investigated through the von Neumann entropy while that for two initially entangled qubits in this PBG reservoir is through concurrence. Dynamics of these measurements are solved in use of the fractional calculus which has been shown appropriate for the systems with non-Markovian dynamics. Entropy dynamics of the single qub...

  19. X-band frequency response and electromagnetic interference shielding in multiferroic BiFeO3 nanomaterials

    Science.gov (United States)

    Reshi, Hilal Ahmad; Singh, Avanish Pratap; Pillai, Shreeja; Para, Touseef Ahmad; Dhawan, S. K.; Shelke, Vilas

    2016-10-01

    The presence of electric dipoles, magnetic dipoles and mobile charges is a prerequisite for electromagnetic interference (EMI) shielding materials. Here, we demonstrate that multiferroic compound with incipient ensemble of electric and magnetic dipoles can perform as an EMI shielding material. We synthesized single phase BiFeO3 nanomaterial and studied complex electromagnetic properties in an X-band frequency region. A shielding effectiveness up to 11 dB with a major contribution from absorption was observed in the BiFeO3 nanomaterials. An auxiliary functionality of radiation shielding is revealed in the multiferroic BiFeO3 compound.

  20. Polygonal deformation bands in sandstone

    Science.gov (United States)

    Antonellini, Marco; Nella Mollema, Pauline

    2017-04-01

    We report for the first time the occurrence of polygonal faults in sandstone, which is compelling given that layer-bound polygonal fault systems have been observed so far only in fine-grained sediments such as clay and chalk. The polygonal faults are dm-wide zones of shear deformation bands that developed under shallow burial conditions in the lower portion of the Jurassic Entrada Fm (Utah, USA). The edges of the polygons are 1 to 5 meters long. The shear deformation bands are organized as conjugate faults along each edge of the polygon and form characteristic horst-like structures. The individual deformation bands have slip magnitudes ranging from a few mm to 1.5 cm; the cumulative average slip magnitude in a zone is up to 10 cm. The deformation bands heaves, in aggregate form, accommodate a small isotropic horizontal extension (strain Crosscutting relationships are rare. The interactions of the deformation bands are similar to those of mode I opening fractures. Density inversion, that takes place where under-compacted and over-pressurized layers (Carmel Fm) lay below normally compacted sediments (Entrada Sandstone), may be an important process for polygonal deformation bands formation. The gravitational sliding and soft sediment structures typically observed within the Carmel Fm support this hypothesis. Soft sediment deformation may induce polygonal faulting in the section of the Entrada Sandstone just above the Carmel Fm. The permeability of the polygonal deformation bands is approximately 10-14 to 10-13 m2, which is less than the permeability of the host, Entrada Sandstone (range 10-12 to 10-11 m2). The documented fault networks have important implications for evaluating the geometry of km-scale polygonal fault systems in the subsurface, top seal integrity, as well as constraining paleo-tectonic stress regimes.

  1. Automatic PCM guard-band selector and calibrator

    Science.gov (United States)

    Noda, T. T.

    1974-01-01

    Automatic method for selection of proper guard band eliminates human error and speeds up calibration process. There is also an option which allows a single channel to be calibrated, independently of other channels. Entire system is designed on 3- by 4-inch printed-circuit cards and may be used with any pulse code modulation system.

  2. Oxygen Isotope Variability within Nautilus Shell Growth Bands.

    Directory of Open Access Journals (Sweden)

    Benjamin J Linzmeier

    Full Text Available Nautilus is often used as an analogue for the ecology and behavior of extinct externally shelled cephalopods. Nautilus shell grows quickly, has internal growth banding, and is widely believed to precipitate aragonite in oxygen isotope equilibrium with seawater. Pieces of shell from a wild-caught Nautilus macromphalus from New Caledonia and from a Nautilus belauensis reared in an aquarium were cast in epoxy, polished, and then imaged. Growth bands were visible in the outer prismatic layer of both shells. The thicknesses of the bands are consistent with previously reported daily growth rates measured in aquarium reared individuals. In situ analysis of oxygen isotope ratios using secondary ion mass spectrometry (SIMS with 10 μm beam-spot size reveals inter- and intra-band δ18O variation. In the wild-caught sample, a traverse crosscutting 45 growth bands yielded δ18O values ranging 2.5‰, from +0.9 to -1.6 ‰ (VPDB, a range that is larger than that observed in many serial sampling of entire shells by conventional methods. The maximum range within a single band (~32 μm was 1.5‰, and 27 out of 41 bands had a range larger than instrumental precision (±2 SD = 0.6‰. The results from the wild individual suggest depth migration is recorded by the shell, but are not consistent with a simple sinusoidal, diurnal depth change pattern. To create the observed range of δ18O, however, this Nautilus must have traversed a temperature gradient of at least ~12°C, corresponding to approximately 400 m depth change. Isotopic variation was also measured in the aquarium-reared sample, but the pattern within and between bands likely reflects evaporative enrichment arising from a weekly cycle of refill and replacement of the aquarium water. Overall, this work suggests that depth migration behavior in ancient nektonic mollusks could be elucidated by SIMS analysis across individual growth bands.

  3. Oxygen Isotope Variability within Nautilus Shell Growth Bands

    Science.gov (United States)

    2016-01-01

    Nautilus is often used as an analogue for the ecology and behavior of extinct externally shelled cephalopods. Nautilus shell grows quickly, has internal growth banding, and is widely believed to precipitate aragonite in oxygen isotope equilibrium with seawater. Pieces of shell from a wild-caught Nautilus macromphalus from New Caledonia and from a Nautilus belauensis reared in an aquarium were cast in epoxy, polished, and then imaged. Growth bands were visible in the outer prismatic layer of both shells. The thicknesses of the bands are consistent with previously reported daily growth rates measured in aquarium reared individuals. In situ analysis of oxygen isotope ratios using secondary ion mass spectrometry (SIMS) with 10 μm beam-spot size reveals inter- and intra-band δ18O variation. In the wild-caught sample, a traverse crosscutting 45 growth bands yielded δ18O values ranging 2.5‰, from +0.9 to -1.6 ‰ (VPDB), a range that is larger than that observed in many serial sampling of entire shells by conventional methods. The maximum range within a single band (~32 μm) was 1.5‰, and 27 out of 41 bands had a range larger than instrumental precision (±2 SD = 0.6‰). The results from the wild individual suggest depth migration is recorded by the shell, but are not consistent with a simple sinusoidal, diurnal depth change pattern. To create the observed range of δ18O, however, this Nautilus must have traversed a temperature gradient of at least ~12°C, corresponding to approximately 400 m depth change. Isotopic variation was also measured in the aquarium-reared sample, but the pattern within and between bands likely reflects evaporative enrichment arising from a weekly cycle of refill and replacement of the aquarium water. Overall, this work suggests that depth migration behavior in ancient nektonic mollusks could be elucidated by SIMS analysis across individual growth bands. PMID:27100183

  4. Securing Major Events

    International Nuclear Information System (INIS)

    Loeoef, Susanna

    2013-01-01

    When asked why the IAEA should provide nuclear security support to countries that organize large public events, Nuclear Security Officer Sophia Miaw answers quickly and without hesitation. ''Imagine any major public event such as the Olympics, a football championship, or an Expo. If a dirty bomb were to be exploded at a site where tens of thousands of people congregate, the radioactive contamination would worsen the effects of the bomb, increase the number of casualties, impede a rapid emergency response, and cause long term disruption in the vicinity,'' she said. Avoiding such nightmarish scenarios is the driving purpose behind the assistance the IAEA offers States that host major sporting or other public events. The support can range from a single training course to a comprehensive programme that includes threat assessment, training, loaned equipment and exercises. The type and scope of assistance depends on the host country's needs. ''We incorporate nuclear security measures into their security plan. We don't create anything new,'' Miaw said

  5. William Band at Yenching University

    Science.gov (United States)

    Hu, Danian

    2008-04-01

    William Band (1906-1993) has been widely remembered by his American colleagues and students as ``a fine physicist and teacher,'' who taught at Washington State University in Pullman between 1949 and 1971 and authored Introduction to Quantum Statistics (1954) and Introduction to Mathematical Physics (1959). Not many, however, knew much about Band's early career, which was very ``uncommon and eventful.'' Born in England, Band graduated from University of Liverpool in 1927 with an MsSc degree in physics. Instead of pursuing his Ph.D. at Cambridge, he chose to teach physics at Yenching University, a prestigious Christian university in Beijing, China. Arriving in 1929, Band established his career at Yenching, where he taught and researched the theory of relativity and quantum mechanics, pioneered the study on low-temperature superconductivity in China, founded the country's first graduate program in physics, and chaired the Physics Department for 10 years until he fled from Yenching upon hearing of the attack on Pearl Harbor. It took him two years to cross Japanese occupied areas under the escort of the Communist force; he left China in early 1945. This presentation will explore Band's motivation to work in China and his contributions to the Chinese physics research and education.

  6. Photoionization bands of rubidium molecule

    Science.gov (United States)

    Rakić, M.; Pichler, G.

    2018-03-01

    We studied the absorption spectrum of dense rubidium vapor generated in a T-type sapphire cell with a special emphasis on the structured photoionization continuum observed in the 200-300 nm spectral region. The photoionization spectrum has a continuous atomic contribution with a pronounced Seaton-Cooper minimum at about 250 nm and a molecular photoionization contribution with many broad bands. We discuss the possible origin of the photoionization bands as stemming from the absorption from the ground state of the Rb2 molecule to excited states of Rb2+* and to doubly excited autoionizing states of Rb2** molecule. All these photoionization bands are located above the Rb+ and Rb2+ ionization limits.

  7. Band-in-band segregation of multidisperse granular mixtures

    NARCIS (Netherlands)

    Newey, M.; Ozik, J.; van der Meer, S.M.

    2004-01-01

    Radial and axial segregation is investigated experimentally in polydisperse mixtures of granular materials rotated in a long, partly filled, horizontal cylinder. Radial segregation by size is observed in all polydisperse mixtures. Axial segregation, with smaller-size particles forming bands within

  8. Identification of parvalbumin and two new thermolabile major allergens of Thunnus tonggol using a proteomics approach.

    Science.gov (United States)

    Rosmilah, Misnan; Shahnaz, Murad; Meinir, Jones; Masita, Arip; Noormalin, Abdullah; Jamaluddin, Mohamed

    2013-01-01

    The longtail tuna (Thunnus tonggol) is widely consumed in Asia. Parvalbumin, the main major allergen of fish, has been well identified in multiple fish species, yet little is known about the allergenic proteins in T. tonggol. Thus, the aim of this study was to characterize the major allergens of T. tonggol using a proteomics approach. Raw and boiled extracts of the fish were prepared. Fish proteins were separated by means of SDS-PAGE and two-dimensional (2-DE) electrophoresis. 1-DE immunoblotting of raw extract was performed with sera from fish-allergic patients. Ten sera were further analysed by 2-DE immunoblotting. Selected major allergenic protein spots were excised, trypsin digested and analysed by means of mass spectrometry. SDS-PAGE of raw extract revealed 26 protein fractions, while boiled extract demonstrated fewer bands. The 2-DE gel profile of the raw extract further fractionated the protein bands to more than 100 distinct protein spots. 1-DE immunoblotting of raw extract exhibited two thermolabile protein fractions of 42 and 51 kDa as the major allergens, while the boiled extract only revealed a single IgE-binding band at 151 kDa. 2-DE immunoblotting of raw extract further detected numerous major IgE-reactive spots of 11-13, 42 and 51 kDa. Mass spectrometry analysis of the peptides generated from the 12, 42 and 51 kDa digested spots indicated that these spots were parvalbumin, creatine kinase and enolase, respectively. In addition to parvalbumin, two new thermolabile allergens were identified as major allergenic proteins of T. tonggol. This study proved that both thermostable and thermolabile proteins are important in local tuna allergy and should be included in diagnostic strategies.

  9. Radiology of vertical banded gastroplasty

    International Nuclear Information System (INIS)

    Leekam, R.N.; Deitel, M.; Shankar, L.; Salsberg, B.

    1987-01-01

    Vertical banded gastroplasty is now the most common procedure for the surgical treatment of obesity. In the past 4 years 120 patients have been referred for radiologic examination. This exhibit describes the normal and abnormal findings in many of these patients. The authors divided radiologic abnormalities into three groups: abnormalities of the partition, abnormalities of the banded channel, and ulcers and extragastric leaks. The authors' examination technique has been adapted from those described by others, our important addition being the preliminary precontrast film, on which the staple lines can be examined. This has proved most effective in the detection of partition defects

  10. Simulation of nanowire tunneling transistors: From the Wentzel-Kramers-Brillouin approximation to full-band phonon-assisted tunneling

    Science.gov (United States)

    Luisier, Mathieu; Klimeck, Gerhard

    2010-04-01

    Nanowire band-to-band tunneling field-effect transistors (TFETs) are simulated using the Wentzel-Kramers-Brillouin (WKB) approximation and an atomistic, full-band quantum transport solver including direct and phonon-assisted tunneling (PAT). It is found that the WKB approximation properly works if one single imaginary path connecting the valence band (VB) and the conduction band (CB) dominates the tunneling process as in direct band gap semiconductors. However, PAT is essential in Si and Ge nanowire TFETs where multiple, tightly-coupled, imaginary paths exist between the VB and the CB.

  11. Evolution of an Intense Warm Frontal Precipitation Band During the GPM Cold-Season Precipitation Experiment (GCPEx)

    Science.gov (United States)

    Colle, Brian A.; Naeger, Aaron R.; Molthan, Andrew

    2017-01-01

    The band developed with low-level deformation and frontogenesis along the sloping warm frontal zone, and the vertical motions became large enough to produce graupel on the south side of the band. Embedded convective cells developed earlier in our GCPEx event, but the frontogenesis was weak then and banding was limited. As the deformation increased the stability also increased near the banding location (MPV* 0), which favored the development of single band. Through sensitivity studies (not shown) we found that latent heating helps increase the frontal circulations and resulting band development. Latent cooling also helps increase the frontogenesis given the evaporative and sublimation cooling within the frontal precipitation.

  12. Simple Front-End Concept for the Complex Challenges of Multi-Band Communications

    DEFF Research Database (Denmark)

    Buskgaard, Emil Feldborg; Tatomirescu, Alexandru; Barrio, Samantha Caporal Del

    2015-01-01

    This paper proposes a new architecture for mobile phone front-ends that dramatically reduces the complexity of multi-band smart phones. Traditional smart phone front-ends consist of many parallel transmit (Tx) and receive (Rx) chains each dedicated to a single band. The proposed architecture simp...... bands realistic. Current 5G investigations show that the advantages of flexible front-ends will be even bigger as technology moves toward software defined radio. \\end{abstract}...

  13. Band gap engineering for graphene by using Na+ ions

    International Nuclear Information System (INIS)

    Sung, S. J.; Lee, P. R.; Kim, J. G.; Ryu, M. T.; Park, H. M.; Chung, J. W.

    2014-01-01

    Despite the noble electronic properties of graphene, its industrial application has been hindered mainly by the absence of a stable means of producing a band gap at the Dirac point (DP). We report a new route to open a band gap (E g ) at DP in a controlled way by depositing positively charged Na + ions on single layer graphene formed on 6H-SiC(0001) surface. The doping of low energy Na + ions is found to deplete the π* band of graphene above the DP, and simultaneously shift the DP downward away from Fermi energy indicating the opening of E g . The band gap increases with increasing Na + coverage with a maximum E g ≥0.70 eV. Our core-level data, C 1s, Na 2p, and Si 2p, consistently suggest that Na + ions do not intercalate through graphene, but produce a significant charge asymmetry among the carbon atoms of graphene to cause the opening of a band gap. We thus provide a reliable way of producing and tuning the band gap of graphene by using Na + ions, which may play a vital role in utilizing graphene in future nano-electronic devices.

  14. Assessment of multipath and shadowing effects on UHF band in ...

    African Journals Online (AJOL)

    In this work, the multi-path and shadowing effects on signal impairment were investigated through the use of empirical and semi-empirical path loss models analysis in built-up environments. Electromagnetic field strength measurements were conducted using four television transmitters at UHF bands along four major routes ...

  15. What does an isolated cerebrospinal fluid band mean: a tertiary centre experience

    Directory of Open Access Journals (Sweden)

    Turan Poyraz

    2015-04-01

    Full Text Available Introduction: The presence of oligoclonal bands in cerebrospinal fluid of multiple sclerosis patients is now well established to support the clinical diagnosis. On the other hand, a single band response can represent the initial stage of an oligoclonal response, before the other antibody clones become visible. Method: The aim of the current study was to evaluate the presence of an isolated cerebrospinal fluid single immunoglobulin band, and to analyse the clinical and radiological diagnosis of the samples with a single immunoglobulin band. In this study, 3524 cerebrospinal fluid samples were re-examined using agarose gel isoelectric focusing, and ones with an isolated cerebrospinal fluid immunoglobulin band were detected. Results: A single band in cerebrospinal fluid was detected in 1.4% samples. A clinically isolated syndrome was diagnosed in 27.5%of them, relapsing remitting multiple sclerosis in 49%, secondary progressive multiple sclerosis in 11.8%, and radiologically isolated syndrome in 2%. No primary progressive multiple sclerosis patient was found. All Barkhoff criteria were met in 90.1% of them. The remaining were diagnosed with other inflammatory neurological diseases (9.8%. Conclusion: The presence of an isolated cerebrospinal fluid monoclonal immunoglobulin band is rare. Although most of the samples were diagnosed as multiple sclerosis according to both clinical and paraclinical (magnetic resonance imaging parameters, they had only a single immunoglobulin band in cerebrospinal fluid. Not only oligoclonal bands, but also an isolated cerebrospinal fluid single band might be a cornerstone for the diagnosis of multiple sclerosis at least for some patients.

  16. A single-chain fusion molecule consisting of peptide, major histocompatibility gene complex class I heavy chain and beta2-microglobulin can fold partially correctly, but binds peptide inefficiently

    DEFF Research Database (Denmark)

    Sylvester-Hvid, C; Buus, S

    1999-01-01

    of a recombinant murine MHC-I molecule, which could be produced in large amounts in bacteria. The recombinant MHC-I protein was expressed as a single molecule (PepSc) consisting of the antigenic peptide linked to the MHC-I heavy chain and further linked to human beta2-microglobulin (hbeta2m). The PepSc molecule...... electrophoresis (SDS-PAGE). Serological analysis revealed the presence of some, but not all, MHC-I-specific epitopes. Biochemically, PepSc could bind peptide, however, rather ineffectively. We suggest that a partially correctly refolded MHC-I has been obtained....

  17. Correlations in a band insulator

    Czech Academy of Sciences Publication Activity Database

    Sentef, M.; Kuneš, Jan; Werner, P.; Kampf, A. P.

    2009-01-01

    Roč. 80, č. 15 (2009), 155116/1-155116/7 ISSN 1098-0121 Institutional research plan: CEZ:AV0Z10100521 Keywords : electronic correlations * dynamical mean-field theory * band insulator Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.475, year: 2009

  18. Metaphyseal bands in osteogenesis imperfecta

    Directory of Open Access Journals (Sweden)

    Suresh S

    2010-01-01

    Full Text Available An increasing number of patients with osteogenesis imperfecta are undergoing pamidronate therapy to prevent the incidence of fragility fractures. The authors herein report a child aged 3 years who received five cycles of pamidronate, resulting in metaphyseal bands, known as "zebra lines."

  19. Singing in the Band Rehearsal.

    Science.gov (United States)

    Wolbers, Mark

    2002-01-01

    Explains how singing can be incorporated into the band rehearsal. Discusses how to improve student aural skills by including singing in the rehearsal and the benefits of having students sing. Describes how music teachers can use songs or chorales in the classroom. (CMK)

  20. Dual band metamaterial perfect absorber based on Mie resonances

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xiaoming; Lan, Chuwen; Li, Bo; Zhou, Ji, E-mail: zhouji@tsinghua.edu.cn [State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China); Bi, Ke [School of Science, Beijing University of Posts and Telecommunications, Beijing 100876 (China); Zhao, Qian [State Key Lab of Tribology, Department of Precision Instruments and Mechanology, Tsinghua University, Beijing 100084 (China)

    2016-08-08

    We numerically and experimentally demonstrated a polarization insensitive dual-band metamaterial perfect absorber working in wide incident angles based on the two magnetic Mie resonances of a single dielectric “atom” with simple structure. Two absorption bands with simulated absorptivity of 99% and 96%, experimental absorptivity of 97% and 94% at 8.45 and 11.97 GHz were achieved due to the simultaneous magnetic and electric resonances in dielectric “atom” and copper plate. Mie resonances of dielectric “atom” provide a simple way to design metamaterial perfect absorbers with high symmetry.

  1. Broad-Band Activatable White-Opsin.

    Directory of Open Access Journals (Sweden)

    Subrata Batabyal

    Full Text Available Currently, the use of optogenetic sensitization of retinal cells combined with activation/inhibition has the potential to be an alternative to retinal implants that would require electrodes inside every single neuron for high visual resolution. However, clinical translation of optogenetic activation for restoration of vision suffers from the drawback that the narrow spectral sensitivity of an opsin requires active stimulation by a blue laser or a light emitting diode with much higher intensities than ambient light. In order to allow an ambient light-based stimulation paradigm, we report the development of a 'white-opsin' that has broad spectral excitability in the visible spectrum. The cells sensitized with white-opsin showed excitability at an order of magnitude higher with white light compared to using only narrow-band light components. Further, cells sensitized with white-opsin produced a photocurrent that was five times higher than Channelrhodopsin-2 under similar photo-excitation conditions. The use of fast white-opsin may allow opsin-sensitized neurons in a degenerated retina to exhibit a higher sensitivity to ambient white light. This property, therefore, significantly lowers the activation threshold in contrast to conventional approaches that use intense narrow-band opsins and light to activate cellular stimulation.

  2. Valence band photoemission studies of clean metals

    Energy Technology Data Exchange (ETDEWEB)

    Wehner, P.S.

    1978-04-01

    The application of Angle-Resolved Photoelectron Spectroscopy (ARPES) to crystalline solids and the utilization of such studies to illuminate several questions concerning the detailed electronic structure of such materials, are discussed. Specifically, by construction of a Direct Transition (DT) model and the utilization of energy-dependent angle-resolved normal photoemission in the photon energy range 32 eV < or = h..nu.. < or = 200 eV, the bulk band structure of copper is experimentally mapped out along three different directions in the Brillouin Zone; GAMMA to K, GAMMA to L, and GAMMA to X. In addition, various effects which influence the obtainable resolution in vector k-space, namely, thermal disorder, momentum broadening, and band mixing, are discussed and are shown to place severe limitations on the applicability of the DT model. Finally, a model for Angle-Resolved X-ray Photoelectron Spectroscopy (ARXPS) based on the symmetry of the initial-state wavefunctions is presented and compared to experimental results obtained from copper single crystals.

  3. Multiple band structures in 70Ge

    Science.gov (United States)

    Haring-Kaye, R. A.; Morrow, S. I.; Döring, J.; Tabor, S. L.; Le, K. Q.; Allegro, P. R. P.; Bender, P. C.; Elder, R. M.; Medina, N. H.; Oliveira, J. R. B.; Tripathi, Vandana

    2018-02-01

    High-spin states in 70Ge were studied using the 55Mn(18O,p 2 n ) fusion-evaporation reaction at a beam energy of 50 MeV. Prompt γ -γ coincidences were measured using the Florida State University Compton-suppressed Ge array consisting of three Clover detectors and seven single-crystal detectors. An investigation of these coincidences resulted in the addition of 31 new transitions and the rearrangement of four others in the 70Ge level scheme, providing a more complete picture of the high-spin decay pattern involving both positive- and negative-parity states with multiple band structures. Spins were assigned based on directional correlation of oriented nuclei ratios, which many times also led to unambiguous parity determinations based on the firm assignments for low-lying states made in previous work. Total Routhian surface calculations, along with the observed trends in the experimental kinematic moment of inertia with rotational frequency, support the multiquasiparticle configurations of the various crossing bands proposed in recent studies. The high-spin excitation spectra predicted by previous shell-model calculations compare favorably with the experimental one determined from this study.

  4. Urban High-Resolution Precipitation Product: Combining C-Band and Local X-Band Radar Data

    Science.gov (United States)

    Lengfeld, Katharina; Clemens, Marco; Münster, Hans; Ament, Felix

    2014-05-01

    Modelling precipitation induced floods and their impact on flood-prone regions is one of the biggest challenges for hydrometeorological forecasters. The largest source of error in flood forecasting systems is uncertainty in precipitation estimation. In state of the art rainfall-runoff models, precipitation fields from C-band radars are used as input with temporal resolution in the order of 5 minutes and spatial resolution in the order of kilometres. These radars cannot observe the small scale structure of rain events that influences runoff especially in impermeable urban areas. Therefore, precipitation fields with higher spatial and temporal resolution would improve flood forecasting. In recent years radar systems operating in the X-band frequency range have been developed to provide precipitation fields for areas of special interest in higher temporal (1 min or below) and higher spatial resolution (250 m or below) in complementation to nationwide radar networks. However single X-band radars are highly influenced by attenuation. Within the project Precipitation and Attenuation Estimates from a High-Resolution Weather Radar Network (PATTERN) the University of Hamburg and the Max-Planck-Institute for Meteorology operate a single X-band radar covering the city of Hamburg, Germany. The radar provides precipitation fields with temporal resolution of 30 s and range resolution of 60 m. The area is also covered by the C-band radar Fuhlsbüttel operated by the German Weather Service (DWD) that gives precipitation estimates with a temporal resolution of 5 min and a range resolution of 1 km. We will introduce a method to merge the precipitation fields derived from the X-band radar into the precipitation field provided by the C-band radar Fuhlsbüttel. The observations of radar Fuhlsbüttel will also be integrated in the correction of the attenuated measurements of the X-band radar. The merged precipitation field of both radars will be a valid product to improve rainfall

  5. Major Depression Among Adults

    Science.gov (United States)

    ... Depressive Episode Among Adolescents Data Sources Share Major Depression Definitions Major depression is one of the most common mental disorders in the United States. For some individuals, major depression can result in severe impairments that interfere with ...

  6. Linear methods in band theory

    DEFF Research Database (Denmark)

    Andersen, O. Krogh

    1975-01-01

    Two approximate methods for solving the band-structure problem in an efficient and physically transparent way are presented and discussed in detail. The variational principle for the one-electron Hamiltonian is used in both schemes, and the trial functions are linear combinations of energy......-independent augmented plane waves (APW) and muffin-tin orbitals (MTO), respectively. The secular equations are therefore eigenvalue equations, linear in energy. The trial functions are defined with respect to a muffin-tin (MT) potential and the energy bands depend on the potential in the spheres through potential...... parameters which describe the energy dependence of the logarithmic derivatives. Inside the spheres, the energy-independent APW is that linear combination of an exact solution, at the arbitrary but fixed energy Eν, and its energy derivative which matches continuously and differentiably onto the plane...

  7. NCenter wide band neutrino beam

    International Nuclear Information System (INIS)

    Stutte, L.G.

    1985-01-01

    This memo describes the physical properties of the currently operating N-Center wide band neutrino beam---commonly called the triplet train, following a past tradition of a triplet lens configuration. In reality, in order to gain a larger momentum acceptance and to minimize the angular divergence of the beam, a quadruplet beam (4 lenses) employing point-to-parallel optics at a central momentum of 300 GeV was built. 6 refs., 13 figs., 1 tab

  8. Light-Induced Charge Transport within a Single Asymmetric Nanowire

    Energy Technology Data Exchange (ETDEWEB)

    LIU, CHONG; HWANG, YUN YEONG; JEONG, HOON EIU; YANG, PEIDONG

    2011-01-21

    Artificial photosynthetic systems using semiconductor materials have been explored for more than three decades in order to store solar energy in chemical fuels such as hydrogen. By mimicking biological photosynthesis with two light-absorbing centers that relay excited electrons in a nanoscopic space, a dual-band gap photoelectrochemical (PEC) system is expected to have higher theoretical energy conversion efficiency than a single band gap system. This work demonstrates the vectorial charge transport of photo-generated electrons and holes within a single asymmetric Si/TiO2 nanowire using Kelvin probe force microscopy (KPFM). Under UV illumination, higher surface potential was observed on the n-TiO₂ side, relative to the potential of the p-Si side, as a result of majority carriers’ recombination at the Si/TiO₂ interface. These results demonstrate a new approach to investigate charge separation and transport in a PEC system. This asymmetric nanowire heterostructure, with a dual band gap configuration and simultaneously exposed anode and cathode surfaces represents an ideal platform for the development of technologies for the generation of solar fuels, although better photoanode materials remain to be discovered.

  9. [Gastric band erosion: Alternative management].

    Science.gov (United States)

    Echaverry-Navarrete, Denis José; Maldonado-Vázquez, Angélica; Cortes-Romano, Pablo; Cabrera-Jardines, Ricardo; Mondragón-Pinzón, Erwin Eduardo; Castillo-González, Federico Armando

    2015-01-01

    Obesity is a public health problem, for which the prevalence has increased worldwide at an alarming rate, affecting 1.7 billion people in the world. To describe the technique employed in incomplete penetration of gastric band where endoscopic management and/or primary closure is not feasible. Laparoscopic removal of gastric band was performed in five patients with incomplete penetrance using Foley catheterization in the perforation site that could lead to the development of a gastro-cutaneous fistula. The cases presented include a leak that required surgical lavage with satisfactory outcome, and one patient developed stenosis 3 years after surgical management, which was resolved endoscopically. In all cases, the penetration site closed spontaneously. Gastric band erosion has been reported in 3.4% of cases. The reason for inserting a catheter is to create a controlled gastro-cutaneous fistula, allowing spontaneous closure. Various techniques have been described: the totally endoscopic, hybrid techniques (endoscopic/laparoscopic) and completely laparoscopic. A technique is described here that is useful and successful in cases where the above-described treatments are not viable. Copyright © 2015. Published by Masson Doyma México S.A.

  10. The safety of addition of nitrous oxide to general anaesthesia in at-risk patients having major non-cardiac surgery (ENIGMA-II): a randomised, single-blind trial.

    Science.gov (United States)

    Myles, Paul S; Leslie, Kate; Chan, Matthew T V; Forbes, Andrew; Peyton, Philip J; Paech, Michael J; Beattie, W Scott; Sessler, Daniel I; Devereaux, P J; Silbert, Brendan; Schricker, Thomas; Wallace, Sophie

    2014-10-18

    Nitrous oxide is commonly used in general anaesthesia but concerns exist that it might increase perioperative cardiovascular risk. We aimed to gather evidence to establish whether nitrous oxide affects perioperative cardiovascular risk. We did an international, randomised, assessor-blinded trial in patients aged at least 45 years with known or suspected coronary artery disease having major non-cardiac surgery. Patients were randomly assigned via automated telephone service, stratified by site, to receive a general anaesthetic with or without nitrous oxide. Attending anaesthetists were aware of patients' group assignments, but patients and assessors were not. The primary outcome measure was a composite of death and cardiovascular complications (non-fatal myocardial infarction, stroke, pulmonary embolism, or cardiac arrest) within 30 days of surgery. Our modified intention-to-treat population included all patients randomly assigned to groups and undergoing induction of general anaesthesia for surgery. This trial is registered at ClinicalTrials.gov, number NCT00430989. Of 10,102 eligible patients, we enrolled 7112 patients between May 30, 2008, and Sept 28, 2013. 3543 were assigned to receive nitrous oxide and 3569 were assigned not to receive nitrous oxide. 3483 patients receiving nitrous oxide and 3509 not receiving nitrous oxide were assessed for the primary outcome. The primary outcome occurred in 283 (8%) patients receiving nitrous oxide and in 296 (8%) patients not receiving nitrous oxide (relative risk 0·96, 95% CI 0·83–1·12; p=0·64). Surgical site infection occurred in 321 (9%) patients assigned to nitrous oxide, and in 311 (9%) patients in the no-nitrous oxide group (p=0·61), and severe nausea and vomiting occurred in 506 patients (15%) assigned to nitrous oxide and 378 patients (11%) not assigned to nitrous oxide (pnitrous oxide use in major non-cardiac surgery. Nitrous oxide did not increase the risk of death and cardiovascular complications or

  11. Morphosedimentary features from a major flood on a small, lower-sinuosity, single-thread river: The unknown quantity of overbank deposition, historical-change context, and comparisons with a multichannel river

    Science.gov (United States)

    Joeckel, R. M.; Tucker, S. T.; McMullin, J. D.

    2016-08-01

    This study details overbank sedimentation on a single-thread, bedload stream, the Little Blue River (southeastern Nebraska and northeastern Kansas, USA), which experienced exceptional floods during May-June 2015. Downvalley elongate splays left deposits as thick as 1.2 m and attained areas as great as 156 ha. Splays consisted of fields of large, gravel-covered dunes 0.1 to 0.3 m in height and extensive sand sheets with current ripples or current ripples atop low-relief, long-wavelength dunes. Erosion occurred chiefly in the heads of splays. Levee-floodplain channel complexes were more architecturally complicated, with channel-channel-fringing deposits deposited within 110 m of the banks of the channel. These complexes consisted of two amalgamated components: (1) sediment shadows (vegetation-induced sedimentary structures), as long as 6 m and as high as 0.6 m at their heads, which were produced by the interaction of direct overbank flow with rooted trees; and (2) indistinct, flat-topped bars (some of which were built around eroded remnants of sediment shadows) shaped chiefly by downvalley flood flow. Changes on in-channel bars, the erosion of bank crevasses as large as 70 m in width, and the deposition of large woody debris also occurred during the floods. The earliest aerial photographs (1938) of the study area, taken after multiple low-flow years, show no evidence for recent overbank deposition. Increases in channel-belt area, the number of bars, and the sizes of bars in the Little Blue River took place after 1938, and most rapidly during 1938 to 1950, when annual discharge was increasing. Annual discharge has decreased since ca. 1990, and yet there has been a long-term increase in annual peak from since the 1930s. We surmise that increasing annual peak flows have led to larger floods and, since 1938, serial overbank deposition, as well a wider channel and numerous, large compound bars.

  12. Search for superdeformed bands in {sup 154}Dy

    Energy Technology Data Exchange (ETDEWEB)

    Nisius, D.; Janssens, R.V.F.; Khoo, T.L. [and others

    1995-08-01

    The island of superdeformation in the vicinity of the doubly magic {sup 152}Dy yrast superdeformed (SD) band is thought to be well understood in the framework of cranked mean field calculations. In particular, the calculations suggested that in {sup 154}Dy there should be no yrast or near yrast SD minimum in the 40-60 h spin range, where SD bands in this mass region are thought to be {sup 153}Dy nucleus, it is populated. However, with the presence of five SD bands in the neighboring necessary to ascertain if the addition of one single neutron diminishes the importance of shell effects to the extent that superdeformation can no longer be sustained. In an experiment utilizing the increased resolving power of the early implementation phase of Gammasphere, the reaction {sup 122}Sn({sup 36}S,4n) at 165 MeV was employed to populate high spin states in {sup 154}Dy. In a four-day run with 36 detectors, over one billion triple and higher fold coincidence events were recorded. One new SD band was identified and was assigned to {sup 154}Dy. From comparisons with the Im{sup (2)} moments of inertia of the SD bands in {sup 152}Dy and {sup 153}Dy, a configuration based on (514)9/2{sup 2} neutrons coupled to the {sup 152}Dy SD core was proposed. One unexpected and as yet unexplained feature of this new SD band is that the transition energies are almost identical to those of an excited SD band in {sup 153}Dy. It is also worth noting that the feeding of the yrast states is similar to that achieved by the deexcitation from the ensemble of all entry states in the reaction. This observation emphasizes the statistical nature of the decay-out process. A paper reporting these results was accepted for publication.

  13. Experimental study of absorption band controllable planar metamaterial absorber using asymmetrical snowflake-shaped configuration

    Science.gov (United States)

    Huang, Yongjun; Tian, Yiran; Wen, Guangjun; Zhu, Weiren

    2013-05-01

    In this paper, we systematically discuss a novel planar metamaterial absorber (PMA) based on asymmetrical snowflake-shaped resonators, which can exhibit two distinctly different absorption states, single- and dual-band absorptions, by controlling the branch lengths of the proposed resonators. Numerical simulations and experimental measurements are employed to investigate these two kinds of absorption characteristic in an X-band rectangular waveguide. Both results indicate that such a PMA exhibits a wide range of controllable operating frequencies for the single- and dual-band conditions. The proposed PMA is simple and easy to make, and it has wide applications in the fields of stealth technologies, thermal detectors, and imaging.

  14. Design and analysis of X-band femtosecond linac

    Energy Technology Data Exchange (ETDEWEB)

    Uesaka, M.; Kozawa, T.; Takeshita, A.; Kobayashi, T.; Ueda, T.; Miya, K. [Tokyo Univ., Tokai, Ibaraki (Japan). Nuclear Engineering Research Lab.

    1997-03-01

    Femtosecond quantum phenomena research project is proposed at Nuclear Engineering Research Laboratory, University of Tokyo. The research facility consists of an X-band (11.424GHz) femtosecond electron linac, a femtosecond wavelength tunable laser, two S-band (2.856GHz) picosecond electron linacs and measuring equipments. Especially, we aim to generate a 100 fs (FWHM) electron single bunch with more than 1 nC at the X-band femtosecond linac. Ultrafast processes in radiation physics, chemistry, material science and microscopic electromagnetic phenomena are going to be analyzed there. Here the design and analysis of an X-band femtosecond linac is presented. The simulation of electron dynamics is carried out including magnetic pulse compression by using PARMELA and SUPERFISH. It is found by the simulation that the 600 ps (tail-to-tail) electron emission from a 200 kV thermionic gun can be bunched and compressed to 110 fs (FWHM) with the charge of 0.8 nC which gives 7.3 kA. We plan to use one high power X-band klystron which can supply 60 MW with more than 200 ns pulse duration. The flatness of plateau of the pulse should be 0.2% for stable ultrashort bunch generation. (author)

  15. Neurofeedback training of alpha-band coherence enhances motor performance.

    Science.gov (United States)

    Mottaz, Anais; Solcà, Marco; Magnin, Cécile; Corbet, Tiffany; Schnider, Armin; Guggisberg, Adrian G

    2015-09-01

    Neurofeedback training of motor cortex activations with brain-computer interface systems can enhance recovery in stroke patients. Here we propose a new approach which trains resting-state functional connectivity associated with motor performance instead of activations related to movements. Ten healthy subjects and one stroke patient trained alpha-band coherence between their hand motor area and the rest of the brain using neurofeedback with source functional connectivity analysis and visual feedback. Seven out of ten healthy subjects were able to increase alpha-band coherence between the hand motor cortex and the rest of the brain in a single session. The patient with chronic stroke learned to enhance alpha-band coherence of his affected primary motor cortex in 7 neurofeedback sessions applied over one month. Coherence increased specifically in the targeted motor cortex and in alpha frequencies. This increase was associated with clinically meaningful and lasting improvement of motor function after stroke. These results provide proof of concept that neurofeedback training of alpha-band coherence is feasible and behaviorally useful. The study presents evidence for a role of alpha-band coherence in motor learning and may lead to new strategies for rehabilitation. Copyright © 2014 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  16. Transition quadrupole moments in the superdeformed band of 40Ca

    International Nuclear Information System (INIS)

    Chiara, C.J.; Ideguchi, E.; Devlin, M.; LaFosse, D.R.; Lerma, F.; Reviol, W.; Ryu, S.K.; Sarantites, D.G.; Baktash, C.; Galindo-Uribarri, A.; Carpenter, M.P.; Janssens, R.V.F.; Lauritsen, T.; Lister, C.J.; Reiter, P.; Seweryniak, D.; Fallon, P.; Goergen, A.; Macchiavelli, A.O.; Rudolph, D.

    2003-01-01

    The transition quadrupole moments Q t for the superdeformed band in 40 Ca have been determined through thin-target Doppler-shift attenuation analyses. A best-fit value of Q t =1.30±0.05 e b is obtained when a single value is assumed for the entire band. Fitting separate quadrupole moments for in-band transitions decaying from the high-spin states and the presumably admixed low-spin states results in Q t (high)=1.81 -0.26 +0.41 e b and Q t (low)=1.18 -0.05 +0.06 e b, respectively. Q t values extracted for individual transitions in a Doppler-broadened line-shape analysis also indicate smaller Q t values at lower spins. These results are consistent with the interpretation of this band as an eight-particle-eight-hole superdeformed band with a significant admixture of less-collective configurations at low spins

  17. Engineering flat electronic bands in quasiperiodic and fractal loop geometries

    Energy Technology Data Exchange (ETDEWEB)

    Nandy, Atanu, E-mail: atanunandy1989@gmail.com; Chakrabarti, Arunava, E-mail: arunava_chakrabarti@yahoo.co.in

    2015-11-06

    Exact construction of one electron eigenstates with flat, non-dispersive bands, and localized over clusters of various sizes is reported for a class of quasi-one-dimensional looped networks. Quasiperiodic Fibonacci and Berker fractal geometries are embedded in the arms of the loop threaded by a uniform magnetic flux. We work out an analytical scheme to unravel the localized single particle states pinned at various atomic sites or over clusters of them. The magnetic field is varied to control, in a subtle way, the extent of localization and the location of the flat band states in energy space. In addition to this we show that an appropriate tuning of the field can lead to a re-entrant behavior of the effective mass of the electron in a band, with a periodic flip in its sign. - Highlights: • Exact construction of eigenstates with flat and dispersive bands is reported. • Competition between translational order and growth of aperiodicity is discussed. • The effect of magnetic field on the location of flat band states is shown. • Flux tunable re-entrant behavior of the effective mass of electron is studied.

  18. Design of UWB Planar Monopole Antennas with Etched Spiral Slot on the Patch for Multiple Band-Notched Characteristics

    Directory of Open Access Journals (Sweden)

    Swarup Das

    2015-01-01

    Full Text Available Three types of Ultrawideband (UWB antennas with single, double, and triple notched bands are proposed and investigated for UWB communication applications. The proposed antennas consist of CPW fed monopole with spiral slot etched on the patch. In this paper single, double, and also triple band notches with central frequency of 3.57, 5.12, and 8.21 GHz have been generated by varying the length of a single spiral slot. The proposed antenna is low-profile and of compact size. A stable gain is obtained throughout the operation band except the three notched frequencies. The antennas have omnidirectional and stable radiation patterns across all the relevant bands. Moreover, relatively consistent group delays across the UWB frequencies are noticed for the triple notched band antenna. A prototype of the UWB antenna with triple notched bands is fabricated and the measured results of the antenna are compared with the simulated results.

  19. More on Estimation of Banded and Banded Toeplitz Covariance Matrices

    OpenAIRE

    Berntsson, Fredrik; Ohlson, Martin

    2017-01-01

    In this paper we consider two different linear covariance structures, e.g., banded and bended Toeplitz, and how to estimate them using different methods, e.g., by minimizing different norms. One way to estimate the parameters in a linear covariance structure is to use tapering, which has been shown to be the solution to a universal least squares problem. We know that tapering not always guarantee the positive definite constraints on the estimated covariance matrix and may not be a suitable me...

  20. April 2006. 32 Major Orthopaedic Procedures

    African Journals Online (AJOL)

    user

    2006-04-01

    @yahoo.com,. Objective: This study was aimed at determining the trends in the proportions of major ..... Potter MA, Nixon SJ, Aitken RJ. A 10-year analysis of caseload and weighted workload in a single Health board. Ann R ...

  1. Stent induced gastric wall erosion and endoscopic retrieval of nonadjustable gastric band: a new technique.

    Science.gov (United States)

    Wilson, Todd D; Miller, Nathan; Brown, Nicholas; Snyder, Brad E; Wilson, Erik B

    2013-05-01

    In gastrointestinal surgery, specifically in bariatric surgery, there are many types of fixed bands used for restriction and there are a multitude reasons that might eventually be an impetus for the removal of those bands. Bands consisting of Marlex or non silastic materials can be extremely difficult to remove. Intraoperative complications removing fixed bands include the difficulty in locating the band, inability to remove all of the band, and damage to surrounding structures including gastrotomies. Removal of eroded bands endoscopically may pose less risk. Potentially, forced erosion may be an easier modality than surgery, allowing revision without having to deal with the actual band at the time of definitive revision surgery. A retrospective case series developed from a university single institution bariatric practice setting was utilized. Endpoints for the study include success of band removal, complications, length of time the stent was present, and the type of stent. A total of 15 consecutive cases utilizing endoscopic stenting to actively induce fixed gastric band erosion for subsequent endoscopic removal were reviewed. There was an 87 % success rate in complete band removal with partial removal of the remaining bands that resolved the patient's symptoms. A complication rate of 27 % was recorded among the 15 patients, consisting of pain and/or nausea and vomiting. The mean time period of the placement of the stent prior to removal or attempted removal was 16.3 days. Endoscopic forced erosion of fixed gastric bands is feasible, safe, and may offer an advantage over laparoscopic removal. This technique is especially applicable for gastric obstruction from fixed bands, prior to large and definitive revision surgeries, or anticipated hostile anatomy that might preclude an abdominal operation altogether.

  2. Banded all-optical OFDM super-channels with low-bandwidth receivers.

    Science.gov (United States)

    Song, Binhuang; Zhu, Chen; Corcoran, Bill; Zhuang, Leimeng; Lowery, Arthur James

    2016-08-08

    We propose a banded all-optical orthogonal frequency division multiplexing (AO-OFDM) transmission system based on synthesising a number of truncated sinc-shaped subcarriers for each sub-band. This approach enables sub-band by sub-band reception and therefore each receiver's electrical bandwidth can be significantly reduced compared with a conventional AO-OFDM system. As a proof-of-concept experiment, we synthesise 6 × 10-Gbaud subcarriers in both conventional and banded AO-OFDM systems. With a limited receiver electrical bandwidth, the experimental banded AO-OFDM system shows 2-dB optical signal to noise ratio (OSNR) benefit over conventional AO-OFDM at the 7%-overhead forward error correction (FEC) threshold. After transmission over 800-km of single-mode fiber, ≈3-dB improvement in Q-factor can be achieved at the optimal launch power at a cost of increasing the spectral width by 14%.

  3. Band Subset Selection for Hyperspectral Image Classification

    Directory of Open Access Journals (Sweden)

    Chunyan Yu

    2018-01-01

    Full Text Available This paper develops a new approach to band subset selection (BSS for hyperspectral image classification (HSIC which selects multiple bands simultaneously as a band subset, referred to as simultaneous multiple band selection (SMMBS, rather than one band at a time sequentially, referred to as sequential multiple band selection (SQMBS, as most traditional band selection methods do. In doing so, a criterion is particularly developed for BSS that can be used for HSIC. It is a linearly constrained minimum variance (LCMV derived from adaptive beamforming in array signal processing which can be used to model misclassification errors as the minimum variance. To avoid an exhaustive search for all possible band subsets, two numerical algorithms, referred to as sequential (SQ and successive (SC algorithms are also developed for LCMV-based SMMBS, called SQ LCMV-BSS and SC LCMV-BSS. Experimental results demonstrate that LCMV-based BSS has advantages over SQMBS.

  4. Diffusion properties of band 3 in human erythrocytes

    Science.gov (United States)

    Spector, Jeffrey O.

    The plasma membrane of the human erythrocyte (RBC) is a six fold symmetric network held together at various pinning points by several multi-protein complexes. This unique architecture is what gives the RBC its remarkable material properties and any disruptions to the network can have severe consequences for the cell. Band 3 is a major transmembrane protein that plays the role of linking the fluid lipid bilayer to the cytoskeletal network. To interrogate the structural integrity of the RBC membrane we have tracked individual band 3 molecules in RBCs displaying a variety of pathologies that are all a consequence of membrane or network related defects. These diseases are spherocytosis, elliptocytosis, and pyropokilocytosis. We have also investigated the protein related diseases sickle cell, and south east asian ovalocytosis. To assess the impact that the network has on the dynamic organization of the cell we have also studied the mobility of band 3 in RBC progenitor cells. Individual band 3 molecules were imaged at 120 frames/second and their diffusion coefficients and compartment sizes recorded. The distributions of the compartment sizes combined with the information about the short and long time diffusion of band 3 has given us insight into the architecture of the membrane in normal and diseased cells. The observation that different membrane pathologies can be distinguished, even to the point of different molecular origins of the same disease, implies that the mobility of transmembrane proteins may be a useful tool for characterizing the "health" of the membrane.

  5. A PHOTONIC BAND GAP FIBRE

    DEFF Research Database (Denmark)

    1999-01-01

    An optical fibre having a periodicidal cladding structure provididing a photonic band gap structure with superior qualities. The periodical structure being one wherein high index areas are defined and wherein these are separated using a number of methods. One such method is the introduction...... of additional low index elements, another method is providing elongated elements deformed in relation to a circular cross section. Also described is a cladding structure comprising elongated elements of a material having an index of refraction higher than that of the material adjacent thereto. Using...

  6. High-energy band structure of gold

    DEFF Research Database (Denmark)

    Christensen, N. Egede

    1976-01-01

    The band structure of gold for energies far above the Fermi level has been calculated using the relativistic augmented-plane-wave method. The calculated f-band edge (Γ6-) lies 15.6 eV above the Fermi level is agreement with recent photoemission work. The band model is applied to interpret...

  7. Major Sport Venues

    Data.gov (United States)

    Department of Homeland Security — The Major Public Venues dataset is composed of facilities that host events for the National Association for Stock Car Auto Racing, Indy Racing League, Major League...

  8. Fossilized iron bacteria reveal a pathway to the biological origin of banded iron formation.

    Science.gov (United States)

    Chi Fru, Ernest; Ivarsson, Magnus; Kilias, Stephanos P; Bengtson, Stefan; Belivanova, Veneta; Marone, Federica; Fortin, Danielle; Broman, Curt; Stampanoni, Marco

    2013-01-01

    Debates on the formation of banded iron formations in ancient ferruginous oceans are dominated by a dichotomy between abiotic and biotic iron cycling. This is fuelled by difficulties in unravelling the exact processes involved in their formation. Here we provide fossil environmental evidence for anoxygenic photoferrotrophic deposition of analogue banded iron rocks in shallow marine waters associated with an Early Quaternary hydrothermal vent field on Milos Island, Greece. Trace metal, major and rare earth elemental compositions suggest that the deposited rocks closely resemble banded iron formations of Precambrian origin. Well-preserved microbial fossils in combination with chemical data imply that band formation was linked to periodic massive encrustation of anoxygenic phototrophic biofilms by iron oxyhydroxide alternating with abiotic silica precipitation. The data implicate cyclic anoxygenic photoferrotrophy and their fossilization mechanisms in the construction of microskeletal fabrics that result in the formation of characteristic banded iron formation bands of varying silica and iron oxide ratios.

  9. L-band brightness temperature disaggregation for use with S-band and C-band radiometer data for WCOM

    Science.gov (United States)

    Yao, P.; Shi, J.; Zhao, T.; Cosh, M. H.; Bindlish, R.

    2017-12-01

    There are two passive microwave sensors onboard the Water Cycle Observation Mission (WCOM), which includes a synthetic aperture radiometer operating at L-S-C bands and a scanning microwave radiometer operating from C- to W-bands. It provides a unique opportunity to disaggregate L-band brightness temperature (soil moisture) with S-band C-bands radiometer data. In this study, passive-only downscaling methodologies are developed and evaluated. Based on the radiative transfer modeling, it was found that the TBs (brightness temperature) between the L-band and S-band exhibit a linear relationship, and there is an exponential relationship between L-band and C-band. We carried out the downscaling results by two methods: (1) downscaling with L-S-C band passive measurements with the same incidence angle from payload IMI; (2) downscaling with L-C band passive measurements with different incidence angle from payloads IMI and PMI. The downscaling method with L-S bands with the same incident angle was first evaluated using SMEX02 data. The RMSE are 2.69 K and 1.52 K for H and V polarization respectively. The downscaling method with L-C bands is developed with different incident angles using SMEX03 data. The RMSE are 2.97 K and 2.68 K for H and V polarization respectively. These results showed that high-resolution L-band brightness temperature and soil moisture products could be generated from the future WCOM passive-only observations.

  10. Dirac Cones, Topological Edge States, and Nontrivial Flat Bands in Two-Dimensional Semiconductors with a Honeycomb Nanogeometry

    Directory of Open Access Journals (Sweden)

    E. Kalesaki

    2014-01-01

    Full Text Available We study theoretically two-dimensional single-crystalline sheets of semiconductors that form a honeycomb lattice with a period below 10 nm. These systems could combine the usual semiconductor properties with Dirac bands. Using atomistic tight-binding calculations, we show that both the atomic lattice and the overall geometry influence the band structure, revealing materials with unusual electronic properties. In rocksalt Pb chalcogenides, the expected Dirac-type features are clouded by a complex band structure. However, in the case of zinc-blende Cd-chalcogenide semiconductors, the honeycomb nanogeometry leads to rich band structures, including, in the conduction band, Dirac cones at two distinct energies and nontrivial flat bands and, in the valence band, topological edge states. These edge states are present in several electronic gaps opened in the valence band by the spin-orbit coupling and the quantum confinement in the honeycomb geometry. The lowest Dirac conduction band has S-orbital character and is equivalent to the π-π^{⋆} band of graphene but with renormalized couplings. The conduction bands higher in energy have no counterpart in graphene; they combine a Dirac cone and flat bands because of their P-orbital character. We show that the width of the Dirac bands varies between tens and hundreds of meV. These systems emerge as remarkable platforms for studying complex electronic phases starting from conventional semiconductors. Recent advancements in colloidal chemistry indicate that these materials can be synthesized from semiconductor nanocrystals.

  11. Photonic Band Gap Accelerator Demonstration at Ku-Band.

    CERN Document Server

    Smirnova, Evgenya I; Edwards, Randall L; Kesar, Amit S; Mastovsky, Ivan; Shapiro, Michael A; Temkin, Richard J

    2005-01-01

    We report progress on the design and cold test of a metal Ku-band PBG accelerator structure. The 17.140 GHz 6-cell PBG accelerator structure with reduced long-range wakefields was designed for the experiment. The copper structure was electroformed and cold-tested. Tuning was performed through chemical etching of the rods. Final cold test measurements were found to be in very good agreement with the design. The structure will be installed on the beam line at the accelerator laboratory at Massachusetts Institute of Technology and will be powered with 3 MW of peak power from the Haimson 17.14 GHz klystron. Results of the design, fabrication, cold test and hot test on the Haimson accelerator will be presented.

  12. Dust bands in the asteroid belt

    International Nuclear Information System (INIS)

    Sykes, M.V.; Greenberg, R.; Dermott, S.F.; Nicholson, P.D.; Burns, J.A.

    1989-01-01

    This paper describes the original IRAS observations leading to the discovery of the three dust bands in the asteroid belt and the analysis of data. Special attention is given to an analytical model of the dust band torus and to theories concerning the origin of the dust bands, with special attention given to the collisional equilibrium (asteroid family), the nonequilibrium (random collision), and the comet hypotheses of dust-band origin. It is noted that neither the equilibrium nor nonequilibrium models, as currently formulated, present a complete picture of the IRAS dust-band observations. 32 refs

  13. Modeling C-Band Co-Channel Interference From AeroMACS Omni-Directional Antennas to Mobile Satellite Service Feeder Uplinks

    Science.gov (United States)

    Wilson, Jeffrey D.

    2011-01-01

    A new C-band (5091 to 5150 MHz) airport communications system designated as Aeronautical Mobile Airport Communications System (AeroMACS) is being planned under the Federal Aviation Administration s NextGen program. An interference analysis software program, Visualyse Professional (Transfinite Systems Ltd), is being utilized to provide guidelines on limitations for AeroMACS transmitters to avoid interference with other systems. A scenario consisting of a single omni-directional transmitting antenna at each of the major contiguous United States airports is modeled and the steps required to build the model are reported. The results are shown to agree very well with a previous study.

  14. An integrated Ka/Ku-band payload for personal, mobile and private business communications

    Science.gov (United States)

    Hayes, Edward J.; Keelty, J. Malcolm

    1991-01-01

    The Canadian Department of Communications has been studying options for a government-sponsored demonstration payload to be launched before the end of the century. A summary of the proposed system concepts and network architectures for providing an advanced private business network service at Ku-band and personal and mobile communications at Ka-band is presented. The system aspects addressed include coverage patterns, traffic capacity, and grade of service, multiple access options as well as special problems, such as Doppler in mobile applications. Earth terminal types and the advanced payload concept proposed in a feasibility study for the demonstration mission are described. This concept is a combined Ka-band/Ku-band payload which incorporates a number of advanced satellite technologies including a group demodulator to convert single-channel-per-carrier frequency division multiple access uplink signals to a time division multiplex downlink, on-board signal regeneration, and baseband switching to support packet switched data operation. The on-board processing capability of the payload provides a hubless VSAT architecture which permits single-hop full mesh interconnectivity. The Ka-band and Ku-band portions of the payload are fully integrated through an on-board switch, thereby providing the capability for fully integrated services, such as using the Ku-band VSAT terminals as gateway stations for the Ka-band personal and mobile communications services.

  15. One-year results of the banded neural response imaging study.

    Science.gov (United States)

    Akin, Istemihan; Mutlu, Murad; Kuran, Gokhan; Dincer, Hilal; Arnold, Laure; Boyle, Patrick

    2008-08-01

    To investigate the relationship between single-channel and banded neural response imaging (NRI) responses and to evaluate whether banded NRI measurements are better correlated to fitting parameters than single-channel NRI measurements. Nineteen profoundly deaf subjects implanted with a HiRes 90K cochlear implant from Advanced Bionics Corporation (Valencia, CA). Neural response imaging thresholds (tNRIs; single-channel and banded tNRIs) were measured intraoperatively; at first fitting; and after 3, 6, and 12 months of implant use. Relationships between those measurements and correlations between those measurements and implant program parameters were investigated. Single-channel and banded tNRI collected at each measurement session. Banded NRI could be recorded reliably and was not more time-consuming than the routine single-channel NRI. Significant correlations (Pearson R; p NRI may be a more appropriate fitting tool than single-channel NRI. However, the sample size was small, and more data are necessary to confirm these findings.

  16. Giemsa C-banding of Barley Chromosomes. I: Banding Pattern Polymorphism

    DEFF Research Database (Denmark)

    Linde-Laursen, Ib

    1978-01-01

    Twenty barley (Hordeum vulgare) lines studied had a common basic chromosome banding pattern. Most bands ranged from medium to very small in size. The most conspicuous banding occurred at or near the centromeres, in the proximal, intercalary parts of most chromosome arms and beside the secondary c...... 7. Seventeen differently banded karyotypes were found. Some banding pattern polymorphisms can be used in cytological and cytogenetic studies....

  17. Photonic band gap structure simulator

    Science.gov (United States)

    Chen, Chiping; Shapiro, Michael A.; Smirnova, Evgenya I.; Temkin, Richard J.; Sirigiri, Jagadishwar R.

    2006-10-03

    A system and method for designing photonic band gap structures. The system and method provide a user with the capability to produce a model of a two-dimensional array of conductors corresponding to a unit cell. The model involves a linear equation. Boundary conditions representative of conditions at the boundary of the unit cell are applied to a solution of the Helmholtz equation defined for the unit cell. The linear equation can be approximated by a Hermitian matrix. An eigenvalue of the Helmholtz equation is calculated. One computation approach involves calculating finite differences. The model can include a symmetry element, such as a center of inversion, a rotation axis, and a mirror plane. A graphical user interface is provided for the user's convenience. A display is provided to display to a user the calculated eigenvalue, corresponding to a photonic energy level in the Brilloin zone of the unit cell.

  18. Broad-band beam buncher

    International Nuclear Information System (INIS)

    Goldberg, D.A.; Flood, W.S.; Arthur, A.A.; Voelker, F.

    1986-01-01

    This patent describes a broad-band beam buncher. This beam buncher consists of: a housing adapted to be eacuated, an electron gun in the housing for producing a beam of electrons, buncher means in the housing forming a buncher cavity which has an entrance opening for receiving the electron beam and an exit opening through which the electron beam passes out of the buncher cavity, a drift tube electrode in the buncher cavity and disposed between the entrance opening and the exit opening with first and second gaps between the drift tube electrode and the entrance and exit openings, the drift tube electrode which has a first drift space through which the electron beam passes in traveling between the entrance and exit openings, modulating means for supplying an ultrahigh frequeny modulating signal to the drift tube electrode for producing velocity modulation of the electrons in the electron beam as the electrons pass through the buncher cavity and the drift tube electrode between the entrance opening and the exit opening, drift space means in the housing forming a second drift space for receiving the velocity modulated electron beam from the exit opening, the velocity modulated electron beam being bunched as it passes along the second drift space, the drift space means has a discharge opening through which the electron beam is discharged from the second drift space after being bunched therein, the modulating means containing a signal source for producing an ultrahigh frequency signal, a transmission line connected between the signal source and the drift tube electrode, and terminating means connected to the drift tube electrode for terminating the transmission line in approximately its characteristic impedance to afford a broad response band with minimum 6 variations therein

  19. Societal risk and major disasters

    International Nuclear Information System (INIS)

    Clement, C.F.

    1989-01-01

    A disaster can be defined as an event, or a series of events, in which a large number of people is adversely affected by a single cause. This definition includes man-made accidents, like that at Chernobyl, as well as the natural disasters that insurance companies are sometimes pleased to describe as Acts of God. In 1986 alone, 12,000 people died and 2.2 million were made homeless by 215 major accidents or disasters. The nature of risk is examined in this paper. (author)

  20. Spins of superdeformed band in {sup 192}Hg

    Energy Technology Data Exchange (ETDEWEB)

    Lauritsen, T.; Khoo, T.L.; Henry, R.G. [and others

    1995-08-01

    Determination of the spins of SD states is the most important challenge in the study of superdeformation. Knowledge of the spin will provide crucial information on SD bands, in particular on the fascinating phenomenon of bands with identical energies and moments of inertia. Angular distribution coefficients of the {gamma}rays decaying out of the {sup 192}Hg SD band were determined using Eurogam data. These coefficients, as well as the spectral shape and multiplicity of the spectrum, are compared with the results of calculations, thereby providing a check on these calculations. From the measured decay multiplicity and the calculated average spin removed per photon (0.3 h), we deduce the average spin {bar I}{sub decay} removed by the {gamma} rays connecting SD and normal states. The spin I{sub SD} of the SD band from which the decay occurs is given by I{sub SD} = {bar I} decay + {bar I} ND, where {bar I} ND is the average spin removed by the normal yrast states. The state from which the major decay out of the SD band occurs is found to have spin 9.5 {plus_minus} 0.8 h. Since angular momentum is (quantized), this leads to a spin assignment of 9 or 10 h. The latter value is favored since the yrast band in the SD well must have only even spin values. This constitutes the first deduction of spin from data in the mass 150 and 190 regions. The spin of 10 h agrees with the spin which is inferred from a model, using the observed moment of inertia (Im){sup (2)}{omega}.

  1. Simulated annealing band selection approach for hyperspectral imagery

    Science.gov (United States)

    Chang, Yang-Lang; Fang, Jyh-Perng; Hsu, Wei-Lieh; Chang, Lena; Chang, Wen-Yen

    2010-09-01

    In hyperspectral imagery, greedy modular eigenspace (GME) was developed by clustering highly correlated bands into a smaller subset based on the greedy algorithm. Unfortunately, GME is hard to find the optimal set by greedy scheme except by exhaustive iteration. The long execution time has been the major drawback in practice. Accordingly, finding the optimal (or near-optimal) solution is very expensive. Instead of adopting the band-subset-selection paradigm underlying this approach, we introduce a simulated annealing band selection (SABS) approach, which takes sets of non-correlated bands for high-dimensional remote sensing images based on a heuristic optimization algorithm, to overcome this disadvantage. It utilizes the inherent separability of different classes embedded in high-dimensional data sets to reduce dimensionality and formulate the optimal or near-optimal GME feature. Our proposed SABS scheme has a number of merits. Unlike traditional principal component analysis, it avoids the bias problems that arise from transforming the information into linear combinations of bands. SABS can not only speed up the procedure to simultaneously select the most significant features according to the simulated annealing optimization scheme to find GME sets, but also further extend the convergence abilities in the solution space based on simulated annealing method to reach the global optimal or near-optimal solution and escape from local minima. The effectiveness of the proposed SABS is evaluated by NASA MODIS/ASTER (MASTER) airborne simulator data sets and airborne synthetic aperture radar images for land cover classification during the Pacrim II campaign. The performance of our proposed SABS is validated by supervised k-nearest neighbor classifier. The experimental results show that SABS is an effective technique of band subset selection and can be used as an alternative to the existing dimensionality reduction method.

  2. The dynamics of a shear band

    Science.gov (United States)

    Giarola, Diana; Capuani, Domenico; Bigoni, Davide

    2018-03-01

    A shear band of finite length, formed inside a ductile material at a certain stage of a continued homogeneous strain, provides a dynamic perturbation to an incident wave field, which strongly influences the dynamics of the material and affects its path to failure. The investigation of this perturbation is presented for a ductile metal, with reference to the incremental mechanics of a material obeying the J2-deformation theory of plasticity (a special form of prestressed, elastic, anisotropic, and incompressible solid). The treatment originates from the derivation of integral representations relating the incremental mechanical fields at every point of the medium to the incremental displacement jump across the shear band faces, generated by an impinging wave. The boundary integral equations (under the plane strain assumption) are numerically approached through a collocation technique, which keeps into account the singularity at the shear band tips and permits the analysis of an incident wave impinging a shear band. It is shown that the presence of the shear band induces a resonance, visible in the incremental displacement field and in the stress intensity factor at the shear band tips, which promotes shear band growth. Moreover, the waves scattered by the shear band are shown to generate a fine texture of vibrations, parallel to the shear band line and propagating at a long distance from it, but leaving a sort of conical shadow zone, which emanates from the tips of the shear band.

  3. Demosaicking Based on Optimization and Projection in Different Frequency Bands

    Directory of Open Access Journals (Sweden)

    Omer OsamaA

    2008-01-01

    Full Text Available Abstract A fast and effective iterative demosaicking algorithm is described for reconstructing a full-color image from single-color filter array data. The missing color values are interpolated on the basis of optimization and projection in different frequency bands. A filter bank is used to decompose an initially interpolated image into low-frequency and high-frequency bands. In the low-frequency band, a quadratic cost function is minimized in accordance with the observation that the low-frequency components of chrominance slowly vary within an object region. In the high-frequency bands, the high-frequency components of the unknown values are projected onto the high-frequency components of the known values. Comparison of the proposed algorithm with seven state-of-the-art demosaicking algorithms showed that it outperforms all of them for 20 images on average in terms of objective quality and that it is competitive with them from the subjective quality and complexity points of view.

  4. Relaxation and cross section effects in valence band photoemission spectroscopy

    International Nuclear Information System (INIS)

    McFeely, F.R.

    1976-09-01

    Various problems relating to the interpretation of valence band x-ray photoemission (XPS) spectra of solids are discussed. The experiments and calculations reported herein deal with the following questions: (1) To what extent do many-body effects manifest themselves in an XPS valence band spectrum, and thus invalidate a direct comparison between the photoemission energy distribution, I(E), and the density of states, N(E), calculated on the basis of ground-state one-electron theory. (2) The effect of the binding-energy-dependent photoemission cross section on I(E) at XPS energies. (3) In favorable cases indicated by (1) and (2) we examine the effect of the interaction of the crystal field with the apparent spin-orbit splittings of core levels observed in XPS spectra. (4) The use of tight binding band structure calculations to parameterize the electronic band structure from XPS and other data is described. (5) The use of high energy angle-resolved photoemission on oriented single crystals to gain orbital symmetry information is discussed. (6) The evolution of the shape of the photoemission energy distribution (of polycrystalline Cu) as a function of photon energy from 50 less than or equal h ω less than or equal 175 is discussed

  5. Prospects after Major Trauma

    NARCIS (Netherlands)

    Holtslag, H.R.

    2007-01-01

    Introduction. After patients survived major trauma, their prospects, in terms of the consequences for functioning, are uncertain, which may impact severely on patient, family and society. The studies in this thesis describes the long-term outcomes of severe injured patients after major trauma. In

  6. Adaptive Confidence Bands for Nonparametric Regression Functions.

    Science.gov (United States)

    Cai, T Tony; Low, Mark; Ma, Zongming

    2014-01-01

    A new formulation for the construction of adaptive confidence bands in non-parametric function estimation problems is proposed. Confidence bands are constructed which have size that adapts to the smoothness of the function while guaranteeing that both the relative excess mass of the function lying outside the band and the measure of the set of points where the function lies outside the band are small. It is shown that the bands adapt over a maximum range of Lipschitz classes. The adaptive confidence band can be easily implemented in standard statistical software with wavelet support. Numerical performance of the procedure is investigated using both simulated and real datasets. The numerical results agree well with the theoretical analysis. The procedure can be easily modified and used for other nonparametric function estimation models.

  7. A 3D printed dual GSM band near isotropic on-package antenna

    KAUST Repository

    Zhen, Su

    2017-10-25

    In this paper, we propose an on-package dual band monopole antenna with near-isotropic radiation pattern for GSM mobile applications. The proposed antenna is well matched for both GSM 900 and 1800 bands and provides decent gain for both the bands (1.67 and 3.27 dBi at 900 MHz and 1800 MHz respectively). The antenna is printed with silver ink on a 3D printed polymer based package. The package houses the GSM electronics and the battery. By optimizing the antenna arms width and length, a near-isotropic radiation pattern is achieved. Unlike the published isotropic antennas which are either single band or large in size, the proposed antenna covers both GSM bands with required bandwidth and is only half wavelength long. The design is low cost and highly suitable for various GSM applications such as localization, in additional to conventional communication applications.

  8. Exercise-induced changes in EEG alpha power depend on frequency band definition mode.

    Science.gov (United States)

    Gutmann, Boris; Hülsdünker, Thorben; Mierau, Julia; Strüder, Heiko K; Mierau, Andreas

    2018-01-01

    In the majority of studies investigating cortical alpha oscillations the alpha frequency is defined as a fixed band thus, neglecting recommendations in the EEG literature to adjust the alpha band according to the individual alpha peak frequency (iAPF). Based on our previous findings indicating exhaustive exercise induces an increase of the post-exercise iAPF, we scrutinized the influence of exercise on post-exercise alpha power by comparing fixed and iAPF-adjusted alpha frequency bands. Resting EEG was recorded from 13 scalp locations in nine subjects before, immediately after as well as ten minutes following an exhaustive exercise protocol on a cycle ergometer. Lower and upper band alpha power was calculated for fixed and iAPF-adjusted frequency bands. Post-exercise lower alpha power increased in both fixed and individually defined bands while a higher upper alpha power was only observed in the fixed frequency band condition. Further, the increase in iAPF was positively related to the changes in fixed-band upper alpha power. It is concluded that lower alpha power is significantly increased following exhaustive exercise whereas the results for upper alpha power are substantially influenced by the method of frequency band definition. Therefore, caution is indicated when analyzing and interpreting exercise-induced changes in alpha power. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. X-BAND KLYSTRON DEVELOPMENT AT SLAC

    Energy Technology Data Exchange (ETDEWEB)

    Vlieks, Arnold E.; /SLAC

    2009-08-03

    The development of X-band klystrons at SLAC originated with the idea of building an X-band Linear Collider in the late 1980's. Since then much effort has been expended in developing a reliable X-band Power source capable of delivering >50 MW RF power in pulse widths >1.5 {micro}s. I will report on some of the technical issues and design strategies which have led to the current SLAC klystron designs.

  10. ANALISIS TIPOGRAFI PADA LOGOTYPE BAND FORGOTTEN

    OpenAIRE

    Atang Riyan Isnandar; wantoro wantoro wantoro

    2016-01-01

    Abstrak Forgotten merupakan band asal kota Bandung yang beraliran death metal. Band ini telah memiliki beberapa album yang cukup sukses. Salah satu faktor yang turut berperan penting dalam album-album Forgotten adalah desain sampul album. Sampul album merupakan identitas dan pesan dari musik yang dibawakan oleh Forgotten. Dalam sampul album, terdapat salah satu elemen visual yaitu Tipografi. Salah satu peran tipografi dalam sampul album Forgotten adalah sebagai logotype dari band. Yang menar...

  11. Computational Design of Flat-Band Material

    Science.gov (United States)

    Hase, I.; Yanagisawa, T.; Kawashima, K.

    2018-02-01

    Quantum mechanics states that hopping integral between local orbitals makes the energy band dispersive. However, in some special cases, there are bands with no dispersion due to quantum interference. These bands are called as flat band. Many models having flat band have been proposed, and many interesting physical properties are predicted. However, no real compound having flat band has been found yet despite the 25 years of vigorous researches. We have found that some pyrochlore oxides have quasi-flat band just below the Fermi level by first principles calculation. Moreover, their valence bands are well described by a tight-binding model of pyrochlore lattice with isotropic nearest neighbor hopping integral. This model belongs to a class of Mielke model, whose ground state is known to be ferromagnetic with appropriate carrier doping and on-site repulsive Coulomb interaction. We have also performed a spin-polarized band calculation for the hole-doped system from first principles and found that the ground state is ferromagnetic for some doping region. Interestingly, these compounds do not include magnetic element, such as transition metal and rare-earth elements.

  12. Computational Design of Flat-Band Material.

    Science.gov (United States)

    Hase, I; Yanagisawa, T; Kawashima, K

    2018-02-26

    Quantum mechanics states that hopping integral between local orbitals makes the energy band dispersive. However, in some special cases, there are bands with no dispersion due to quantum interference. These bands are called as flat band. Many models having flat band have been proposed, and many interesting physical properties are predicted. However, no real compound having flat band has been found yet despite the 25 years of vigorous researches. We have found that some pyrochlore oxides have quasi-flat band just below the Fermi level by first principles calculation. Moreover, their valence bands are well described by a tight-binding model of pyrochlore lattice with isotropic nearest neighbor hopping integral. This model belongs to a class of Mielke model, whose ground state is known to be ferromagnetic with appropriate carrier doping and on-site repulsive Coulomb interaction. We have also performed a spin-polarized band calculation for the hole-doped system from first principles and found that the ground state is ferromagnetic for some doping region. Interestingly, these compounds do not include magnetic element, such as transition metal and rare-earth elements.

  13. Vestibular Findings in Military Band Musicians

    Directory of Open Access Journals (Sweden)

    Zeigelboim, Bianca Simone

    2014-04-01

    Full Text Available Introduction Exposure to music is the subject of many studies because it is related to an individual's professional and social activities. Objectives Evaluate the vestibular behavior in military band musicians. Methods A retrospective cross-sectional study was performed. Nineteen musicians with ages ranging from 21 to 46 years were evaluated (average = 33.7 years and standard deviation = 7.2 years. They underwent anamnesis and vestibular and otolaryngologic evaluation through vectoelectronystagmography. Results The most evident otoneurologic symptoms in the anamnesis were tinnitus (84.2%, hearing difficulties (47.3%, dizziness (36.8%, headache (26.3%, intolerance to intense sounds (21.0%, and earache (15.7%. Seven musicians (37.0% showed vestibular abnormality, which occurred in the caloric test. The abnormality was more prevalent in the peripheral vestibular system, and there was a predominance of irritative peripheral vestibular disorders. Conclusion The alteration in vestibular exam occurred in the caloric test (37.0%. There were changes in the prevalence of peripheral vestibular system with a predominance of irritative vestibular dysfunction. Dizziness was the most significant symptom for the vestibular test in correlation with neurotologic symptoms. The present study made it possible to verify the importance of the labyrinthine test, which demonstrates that this population should be better studied because the systematic exposure to high sound pressure levels may cause major vestibular alterations.

  14. Numerical and Experimental Investigation of Stop-Bands in Finite and Infinite Periodic One-Dimensional Structures

    DEFF Research Database (Denmark)

    Domadiya, Parthkumar Gandalal; Manconi, Elisabetta; Vanali, Marcello

    2016-01-01

    structure. Numerical examples are presented, and results are discussed and validated experimentally. Very good agreement between the numerical and experimental models in terms of stop-bands is shown. In particular, the results show that the stop-bands obtained using a wave approach (applied to a single cell...

  15. Pressure induced FFLO instability in multi-band superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Padilha, I T; Continentino, M A [Instituto de Fisica, Universidade Federal Fluminense, Campus da Praia Vermelha, 24210-340, Niteroi, JR (Brazil)], E-mail: mucio@if.uff.br

    2009-03-04

    Multi-band systems such as inter-metallic and heavy fermion compounds have quasi-particles arising from different orbitals at their Fermi surface. Since these quasi-particles have different masses or densities, there is a natural mismatch of the Fermi wavevectors associated with different orbitals. This makes these materials potential candidates to observe exotic superconducting phases as Sarma or FFLO phases, even in the absence of an external magnetic field. The distinct orbitals coexisting at the Fermi surface are generally hybridized and their degree of mixing can be controlled by external pressure. In this work we investigate the existence of an FFLO type of phase in a two-band BCS superconductor controlled by hybridization. At zero temperature, as hybridization (pressure) increases we find that the BCS state becomes unstable with respect to an inhomogeneous superconducting state characterized by a single wavevector q.

  16. Single-Phase PLLs

    DEFF Research Database (Denmark)

    Golestan, Saeed; Guerrero, Josep M.; Quintero, Juan Carlos Vasquez

    2017-01-01

    Single-phase phase-locked loops (PLLs) are popular for the synchronization and control of single-phase gridconnected converters. They are also widely used for monitoring and diagnostic purposes in the power and energy areas. In recent years, a large number of single-phase PLLs with different...... structures and properties have been proposed in the literature. The main aim of this paper is to provide a review of these PLLs. To this end, the single-phase PLLs are first classified into two major categories: 1) power-based PLLs (pPLLs), and 2) quadrature signal generation-based PLLs (QSG......-PLLs). The members of each category are then described and their pros and cons are discussed. This work provides a deep insight into characteristics of different single-phase PLLs and, therefore, can be considered as a reference for researchers and engineers....

  17. In situ hybridization to cytogenetic bands of yeast artificial chromosomes covering 50% of human Xq24-Xq28 DNA

    Science.gov (United States)

    Montanaro, Vittorio; Casamassimi, Amelia; D'Urso, Michele; Yoon, Jae-Young; Freije, Wadiha; Schlessinger, David; Muenke, Maximilian; Nussbaum, Robert L.; Saccone, Salvatore; Maugeri, Silvana; Santoro, Anna Maria; Motta, Salvatore; Della Valle, Giuliano

    1991-01-01

    From the collection described by Abidi et al., 102 yeast artificial chromosomes (YACs) with human DNA inserts more than 300 kb in length were assigned to chromosomal band positions on early metaphase chromosomes by in situ hybridization using the biotin-avidin method. All the YACs hybridized within the Xq24-Xqter region, supporting the origin of the vast majority of the YACs from single human X-chromosomal sites. With assignments precise to ±0.5 bands, YACs were distributed among cytogenetic bands to roughly equal extents. Thus, there is no gross bias in the cloning of DNA from different bands into large YACs. To test band assignments further, hybridizations were carried out blind, and band positions were then compared with (1) probe localizations in cases in which a reported location was present in one of the YACs; (2) cross-hybridization of a labeled YAC with others in the collection; and (3) hybridization to a panel of DNAs from a series of hybrid cells containing Xq DNA truncated at various regions. Of 31 cases in which YACs contained a probe with a previously reported location, 28 in situ assignments were in agreement, and 14 other assignments, including one of the three discordant with probe localization, were confirmed by YAC cross-hybridization studies. Results with a group of nine YACs were further confirmed with a panel of somatic cell hybrid DNAs from that region. Five YACs hybridized both to Xq25 and to a second site (four in Xq27 and one in Xq28), suggestive of some duplication of DNA of the hybrid cell and perhaps in normal X chromosomes. The in situ assignments are thus sufficient to place YACs easily and systematically within bins of about 7–10 Mb and to detect some possible anomalies. Furthermore, on the basis of expectations for random cloning of DNA in YACs, the assigned YACs probably cover more than 50% of the total Xq24-Xq28 region. This provides one way to initiate the assembly of YAC contigs over extended chromosomal regions. Images

  18. A major safety overhaul

    CERN Multimedia

    2003-01-01

    A redefined policy, a revamped safety course, an environmental project... the TIS (Technical Inspection and Safety) Division has begun a major safety overhaul. Its new head, Wolfgang Weingarten, explains to the Bulletin why and how this is happening.

  19. Allegheny County Major Rivers

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset contains locations of major rivers that flow through Allegheny County. These shapes have been taken from the Hydrology dataset. The Ohio River,...

  20. Teleneonatology: a major tool for the future.

    Science.gov (United States)

    Minton, Stephen; Allan, Mark; Valdes, Wesley

    2014-02-01

    Hospitals have, for centuries, maintained a central position in the health care system, providing care for critically ill patients. Despite being a cornerstone of health care delivery, we are witnessing the beginning of a major transformation in their function. There are several forces driving this transformation, including health care costs, shortage of health care professionals, volume of people with chronic diseases, consumerism, health care reform, and hospital errors. The neonatal intensive care unit (NICU) at Utah Valley Regional Medical Center in Provo, Utah, began an aggressive redesign/quality improvement effort in 1990. It became obvious that our care processes were designed for health care deliverers and not for the families. An ongoing revamp of our care delivery processes was undertaken using significant input from a parent focus meeting, parental interviews, and development of a parent-to-parent support group. As a result of this work, it became obvious we needed a new model to truly empower parents. The idea of "NICU is Home" was born. We elected to make a mind shift, not to focus on what families think, but rather on how they think. Web cams and other video apparatus have been used in a number of NICUs across the country. We decided our equipment requirements would need to include high-resolution cameras, full high-definition video recording, autofocus, audio microphones, automatic noise reduction, and automatic low-light correction. Our conferencing software needed to accommodate multiple users and have multiple-picture capabilities, low band width, and inexpensive technology. It was recognized that a single video camera feed was insufficient to adequately capture the desired amount of information. Verbal communication between parents and their babies' principal care providers is critical. Parents loved the idea of expanding the remote NICU web cam of their baby to a two-way physician-parent communication bedside monitor. Doctors at Utah Valley

  1. Ground state shape and crossing of near spherical and deformed bands in 182Hg

    International Nuclear Information System (INIS)

    Ma, W.C.; Ramayya, A.V.; Hamilton, J.H.; Robinson, S.J.; Barclay, M.E.; Zhao, K.; Cole, J.D.; Zganjar, E.F.; Spejewski, E.H.

    1983-01-01

    The energy levels of 182 Hg have been identified for the first time through comparison of in-beam studies of the reactions 156 154 Gd( 32 S,4n) 184 182 Hg. Levels up to 12 + in 182 Hg were established from γ-γ coincidence and singles measurement. The data establish that the ground state shape is near spherical, and that the ground band is crossed by a well deformed band at 4 + . In contrast to IBA model predictions that the deformed band will rise in energy in 182 Hg compared to 184 Hg, the energies of the deformed levels in 182 Hg continue to drop. 7 references

  2. Spontaneous reduction of the prolapsed stomach in a case of anterior band slippage after laparoscopic adjustable gastric banding.

    Science.gov (United States)

    Darius, T; Aelvoet, Ch; Tollens, T; Vanrykel, J P

    2007-01-01

    Band slippage is a common late complication after laparoscopic adjustable gastric banding. We present the first report in literature of a spontaneous reduction of the prolapsed stomach after band deflation in a case of anterior band slippage.

  3. Transient noise reduction in cochlear implant users: a multi-band approach

    Directory of Open Access Journals (Sweden)

    Karl-Heinz Dyballa

    2016-08-01

    Full Text Available A previously-tested transient noise reduction (TNR algorithm for cochlear implant (CI users was modified to detect and attenuate transients independently across multiple frequency-bands. Since speech and transient noise are often spectrally distinct, we hypothesized that benefits in speech intelligibility can be achieved over the earlier single- band design. Fifteen experienced CI users (49 to 72 years were tested unilaterally using pre-processed stimuli delivered directly to a speech processor. Speech intelligibility in transient and soft stationary noise, subjective sound quality and the recognition of warning signals was investigated in three processing conditions: no TNR (TNRoff, single- band TNR (TNRsgl and multi-band TNR (TNRmult. Notably, TNRmult improved speech reception thresholds (SRTs in cafeteria noise and office noise by up to 3 dB over both TNRoff and TNRsgl, and yielded higher comfort and clarity ratings in cafeteria noise. Our results indicate that multi-band transient noise reduction may be advantageous compared to a single-band approach, and reveal a substantial overall potential for TNR to improve speech perception and listening comfort in CI users.

  4. Solid State KA-Band, Solid State W-Band and TWT Amplifiers, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Phase I of the proposal describes plans to develop a state of the art transmitter for the W-Band and KA -Band Cloud Radar system. Our focus will be concentrated in...

  5. Design and realization of a planar ultrawideband antenna with notch band at 3.5 GHz.

    Science.gov (United States)

    Azim, Rezaul; Islam, Mohammad Tariqul; Misran, Norbahiah; Yatim, Baharudin; Arshad, Haslina

    2014-01-01

    A small antenna with single notch band at 3.5 GHz is designed for ultrawideband (UWB) communication applications. The fabricated antenna comprises a radiating monopole element and a perfectly conducting ground plane with a wide slot. To achieve a notch band at 3.5 GHz, a parasitic element has been inserted in the same plane of the substrate along with the radiating patch. Experimental results shows that, by properly adjusting the position of the parasitic element, the designed antenna can achieve an ultrawide operating band of 3.04 to 11 GHz with a notched band operating at 3.31-3.84 GHz. Moreover, the proposed antenna achieved a good gain except at the notched band and exhibits symmetric radiation patterns throughout the operating band. The prototype of the proposed antenna possesses a very compact size and uses simple structures to attain the stop band characteristic with an aim to lessen the interference between UWB and worldwide interoperability for microwave access (WiMAX) band.

  6. Trigger of the Ubiquitous Surface Band Bending in 3D Topological Insulators

    Directory of Open Access Journals (Sweden)

    E. Frantzeskakis

    2017-11-01

    Full Text Available The main scientific activity in the field of topological insulators (TIs consists of determining their electronic structure by means of magnetotransport and electron spectroscopy with a view to devices based on topological transport. There is, however, a caveat in this approach. There are systematic experimental discrepancies on the electronic structure of the most pristine surfaces of TI single crystals as determined by Shubnikov–de Haas oscillations and by angle-resolved photoelectron spectroscopy (ARPES. We identify intense ultraviolet illumination—that is inherent to an ARPES experiment—as the source for these experimental differences. We explicitly show that illumination is the key parameter, or in other words, the trigger, for energetic shifts of electronic bands near the surface of a TI crystal. This finding revisits the common belief that surface decoration is the principal cause of surface band bending and explains why band bending is not a prime issue in illumination-free magnetotransport studies. Our study further clarifies the role of illumination on the electronic band structure of TIs by revealing its dual effect: downward band bending on very small time scales followed by band flattening at large time scales. Our results therefore allow us to present and predict the complete evolution of the band structure of TIs in a typical ARPES experiment. By virtue of our findings, we pinpoint two alternatives of how to approach flat-band conditions by means of photon-based techniques and we suggest a microscopic mechanism that can explain the underlying phenomena.

  7. Trigger of the Ubiquitous Surface Band Bending in 3D Topological Insulators

    Science.gov (United States)

    Frantzeskakis, E.; Ramankutty, S. V.; de Jong, N.; Huang, Y. K.; Pan, Y.; Tytarenko, A.; Radovic, M.; Plumb, N. C.; Shi, M.; Varykhalov, A.; de Visser, A.; van Heumen, E.; Golden, M. S.

    2017-10-01

    The main scientific activity in the field of topological insulators (TIs) consists of determining their electronic structure by means of magnetotransport and electron spectroscopy with a view to devices based on topological transport. There is, however, a caveat in this approach. There are systematic experimental discrepancies on the electronic structure of the most pristine surfaces of TI single crystals as determined by Shubnikov-de Haas oscillations and by angle-resolved photoelectron spectroscopy (ARPES). We identify intense ultraviolet illumination—that is inherent to an ARPES experiment—as the source for these experimental differences. We explicitly show that illumination is the key parameter, or in other words, the trigger, for energetic shifts of electronic bands near the surface of a TI crystal. This finding revisits the common belief that surface decoration is the principal cause of surface band bending and explains why band bending is not a prime issue in illumination-free magnetotransport studies. Our study further clarifies the role of illumination on the electronic band structure of TIs by revealing its dual effect: downward band bending on very small time scales followed by band flattening at large time scales. Our results therefore allow us to present and predict the complete evolution of the band structure of TIs in a typical ARPES experiment. By virtue of our findings, we pinpoint two alternatives of how to approach flat-band conditions by means of photon-based techniques and we suggest a microscopic mechanism that can explain the underlying phenomena.

  8. Maximizing band gaps in plate structures

    DEFF Research Database (Denmark)

    Halkjær, Søren; Sigmund, Ole; Jensen, Jakob Søndergaard

    2006-01-01

    Band gaps, i.e., frequency ranges in which waves cannot propagate, can be found in elastic structures for which there is a certain periodic modulation of the material properties or structure. In this paper, we maximize the band gap size for bending waves in a Mindlin plate. We analyze an infinite...

  9. Link adaptation in unlicensed radio bands

    NARCIS (Netherlands)

    Haartsen, J.C.; Schutter, George B.W.

    2005-01-01

    This paper presents a new collaborative mechanism for efficient coordination of radio communication devices, in particular addressing the unlicensed ISM band at 2.4 GHz. As the traffic in the ISM band is increasing tremendously, the potential for interference between uncoordinated devices is

  10. Symptomatic mesodiverticular bands in children | Bertozzi | Annals ...

    African Journals Online (AJOL)

    Symptomatic mesodiverticular bands in children. ... Abstract. Objective: The aim of this study was to review the English literature about a rare condition such as symptomatic mesodiverticular bands (MDBs) in children. Background: The MDB is an ... All cases reported an intestinal occlusion as clinical picture. Internal hernia ...

  11. Concert Band Instrumentation: Realities and Remedies.

    Science.gov (United States)

    Rogers, George L.

    1991-01-01

    Suggests ways to solve problems resulting from imbalanced instrumentation in school concert bands. Identifies sources of imbalance. Encourages band directors to plan for correct instrumentation, to match students' characteristics and abilities to instruments, and to recruit students to play needed instruments. Discusses the benefits of balanced…

  12. Low band gap polymers for organic photovoltaics

    DEFF Research Database (Denmark)

    Bundgaard, Eva; Krebs, Frederik C

    2007-01-01

    Low band gap polymer materials and their application in organic photovoltaics (OPV) are reviewed. We detail the synthetic approaches to low band gap polymer materials starting from the early methodologies employing quinoid homopolymer structures to the current state of the art that relies...... in photovoltaic applications and give a tabular overview of rarely applied materials....

  13. Complex band structure and electronic transmission eigenchannels

    DEFF Research Database (Denmark)

    Jensen, Anders; Strange, Mikkel; Smidstrup, Soren

    2017-01-01

    molecular junctions. The molecular junctions show that both the length dependence of the total transmission and the individual transmission eigenvalues can be, almost always, found through the complex band structure. The complex band structure of the semi-conducting material, however, does not predict...

  14. Stop! Look! Listen! for Effective Band Rehearsals.

    Science.gov (United States)

    Townsend, Alfred S.

    2003-01-01

    Discusses how band conductors can develop student skills in three areas: (1) when the conductor stops the band; (2) teaching the students to pay attention and watch the conductor; and (3) improving the student listening skills. Includes information on instructing students to play chorales. (CMK)

  15. Conduction bands in classical periodic potentials

    Indian Academy of Sciences (India)

    a quantum particle in a conduction band and drift at a constant average velocity through the potential as if it were undergoing resonant tunnelling. The classical conduction bands for this potential are determined numerically with high precision. Keywords. PT symmetry; complex trajectories; complex classical mechanics; ...

  16. Artificial Oxide Heterostructures with Tunable Band Gap

    Science.gov (United States)

    2016-12-20

    tunable band gap and band structures in epitaxial grown CaMnO3. The efforts have been devoted to (1) the thin film growth; (2) the tunable optical...plan to pursue a claim for personal or organizational intellectual property? Changes in research objectives (if any): Change in AFOSR Program Officer

  17. Low-Noise Band-Pass Amplifier

    Science.gov (United States)

    Kleinberg, L.

    1982-01-01

    Circuit uses standard components to overcome common limitation of JFET amplifiers. Low-noise band-pass amplifier employs JFET and operational amplifier. High gain and band-pass characteristics are achieved with suitable choice of resistances and capacitances. Circuit should find use as low-noise amplifier, for example as first stage instrumentation systems.

  18. Deformed configurations, band structures and spectroscopic ...

    Indian Academy of Sciences (India)

    2014-03-20

    Mar 20, 2014 ... nuclei, e.g., in 16O (Z = N = 8) [12,13] and 56Ni (Z = N = 28) [14–16], coexisting with the spherical ground configuration. Recently, Hwang et al [2] have observed deformed rotational bands in 82Ge. To our knowledge, these deformed rotational bands have not been studied theoretically so far though there ...

  19. Atomic-Monolayer MoS2 Band-to-Band Tunneling Field-Effect Transistor

    KAUST Repository

    Lan, Yann Wen

    2016-09-05

    The experimental observation of band-to-band tunneling in novel tunneling field-effect transistors utilizing a monolayer of MoS2 as the conducting channel is demonstrated. Our results indicate that the strong gate-coupling efficiency enabled by two-dimensional materials, such as monolayer MoS2, results in the direct manifestation of a band-to-band tunneling current and an ambipolar transport.

  20. Metal-like Band Structures of Ultrathin Si {111} and {112} Surface Layers Revealed through Density Functional Theory Calculations.

    Science.gov (United States)

    Tan, Chih-Shan; Huang, Michael H

    2017-09-04

    Density functional theory calculations have been performed on Si (100), (110), (111), and (112) planes with tunable number of planes for evaluation of their band structures and density of states profiles. The purpose is to see whether silicon can exhibit facet-dependent properties derived from the presence of a thin surface layer having different band structures. No changes have been observed for single to multiple layers of Si (100) and (110) planes with a consistent band gap between the valence band and the conduction band. However, for 1, 2, 4, and 5 Si (111) and (112) planes, metal-like band structures were obtained with continuous density of states going from the valence band to the conduction band. For 3, 6, and more Si (111) planes, as well as 3 and 6 Si (112) planes, the same band structure as that seen for Si (100) and (110) planes has been obtained. Thus, beyond a layer thickness of five Si (111) planes at ≈1.6 nm, normal semiconductor behavior can be expected. The emergence of metal-like band structures for the Si (111) and (112) planes are related to variation in Si-Si bond length and bond distortion plus 3s and 3p orbital electron contributions in the band structure. This work predicts possession of facet-dependent electrical properties of silicon with consequences in FinFET transistor design. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Band-edge engineering for controlled multi-modal nanolasing in plasmonic superlattices

    Science.gov (United States)

    Wang, Danqing; Yang, Ankun; Wang, Weijia; Hua, Yi; Schaller, Richard D.; Schatz, George C.; Odom, Teri W.

    2017-09-01

    Single band-edge states can trap light and function as high-quality optical feedback for microscale lasers and nanolasers. However, access to more than a single band-edge mode for nanolasing has not been possible because of limited cavity designs. Here, we describe how plasmonic superlattices—finite-arrays of nanoparticles (patches) grouped into microscale arrays—can support multiple band-edge modes capable of multi-modal nanolasing at programmed emission wavelengths and with large mode spacings. Different lasing modes show distinct input-output light behaviour and decay dynamics that can be tailored by nanoparticle size. By modelling the superlattice nanolasers with a four-level gain system and a time-domain approach, we reveal that the accumulation of population inversion at plasmonic hot spots can be spatially modulated by the diffractive coupling order of the patches. Moreover, we show that symmetry-broken superlattices can sustain switchable nanolasing between a single mode and multiple modes.

  2. Laparoscopic adjustable gastric banding. A prospective randomized study comparing the Swedish Adjustable Gastric Band and the MiniMizer Extra: one-year results

    Directory of Open Access Journals (Sweden)

    Tomas Abalikšta

    2011-12-01

    Full Text Available Introduction: A number of different adjustable gastric bands are available for laparoscopic adjustable gastric banding(LAGB. Few attempts have been made to compare the influence of band design differences for efficiency and complicationrate and conflicting results have emerged from comparative studies. Aim: To compare SAGB (Swedish Adjustable Gastric Band and MiniMizer Extra adjustable gastric bands. Material and methods: One hundred and three patients were included in the prospective randomized study. Allpatients underwent LAGB. The SAGB was used in 49 and MiniMizer Extra in 54 patients. The primary endpoint wasweight loss, and secondary endpoints were complication rate, correction of co-morbidities and improvement of qualityof life. Results: There were no early complications. A significant difference in the proportion of patients who have reachedgood or excellent weight loss results (≥ 50% of initial excess body mass index loss was found in favour of the Mini-Mizer Extra group (29.6% vs. 8.2%, p = 0.006. No difference was found in other weight loss parameters, resolution ofco-morbidities and improvement of quality of life. One oesophageal dilatation and one leakage were diagnosed in theMiniMizer Extra group. Five band penetrations (9.3% were diagnosed in the MiniMizer Extra group and no penetrationsin the SAGB group (p = 0.069. Conclusions: No major significant differences were found between the compared bands. Further results need to beconfirmed by longer follow-up.

  3. Infrared coagulation versus rubber band ligation in early stage hemorrhoids

    Directory of Open Access Journals (Sweden)

    P.J. Gupta

    2003-10-01

    Full Text Available The ideal therapy for early stages of hemorrhoids is always debated. Some are more effective but are more painful, others are less painful but their efficacy is also lower. Thus, comfort or efficacy is a major concern. In the present randomized study, a comparison is made between infrared coagulation and rubber band ligation in terms of effectiveness and discomfort. One hundred patients with second degree bleeding piles were randomized prospectively to either rubber band ligation (N = 54 or infrared coagulation (N = 46. Parameters measured included postoperative discomfort and pain, time to return to work, relief in incidence of bleeding, and recurrence rate. The mean age was 38 years (range 19-68 years. The mean duration of disease was 17.5 months (range 12 to 34 months. The number of male patients was double that of females. Postoperative pain during the first week was more intense in the band ligation group (2-5 vs 0-3 on a visual analogue scale. Post-defecation pain was more intense with band ligation and so was rectal tenesmus (P = 0.0059. The patients in the infrared coagulation group resumed their duties earlier (2 vs 4 days, P = 0.03, but also had a higher recurrence or failure rate (P = 0.03. Thus, we conclude that band ligation, although more effective in controlling symptoms and obliterating hemorrhoids, is associated with more pain and discomfort to the patient. As infrared coagulation can be conveniently repeated in case of recurrence, it could be considered to be a suitable alternative office procedure for the treatment of early stage hemorrhoids.

  4. X-band photonic band-gap accelerator structure breakdown experiment

    Directory of Open Access Journals (Sweden)

    Roark A. Marsh

    2011-02-01

    Full Text Available In order to understand the performance of photonic band-gap (PBG structures under realistic high gradient, high power, high repetition rate operation, a PBG accelerator structure was designed and tested at X band (11.424 GHz. The structure consisted of a single test cell with matching cells before and after the structure. The design followed principles previously established in testing a series of conventional pillbox structures. The PBG structure was tested at an accelerating gradient of 65  MV/m yielding a breakdown rate of two breakdowns per hour at 60 Hz. An accelerating gradient above 110  MV/m was demonstrated at a higher breakdown rate. Significant pulsed heating occurred on the surface of the inner rods of the PBG structure, with a temperature rise of 85 K estimated when operating in 100 ns pulses at a gradient of 100  MV/m and a surface magnetic field of 890  kA/m. A temperature rise of up to 250 K was estimated for some shots. The iris surfaces, the location of peak electric field, surprisingly had no damage, but the inner rods, the location of the peak magnetic fields and a large temperature rise, had significant damage. Breakdown in accelerator structures is generally understood in terms of electric field effects. These PBG structure results highlight the unexpected role of magnetic fields in breakdown. The hypothesis is presented that the moderate level electric field on the inner rods, about 14  MV/m, is enhanced at small tips and projections caused by pulsed heating, leading to breakdown. Future PBG structures should be built to minimize pulsed surface heating and temperature rise.

  5. [Major's and Schirmer's Gaustad].

    Science.gov (United States)

    Hvattum, Mari

    2016-07-01

    The psychiatrist Herman Wedel Major planned Gaustad asylum in collaboration with his brother-in-law, the architect Heinrich Ernst Schirmer. The planning of Gaustad took place in parallel with the preparation of the first Norwegian Mental Health Act, adopted by the Storting on 30 July 1848, and Gaustad's architecture provides a good illustration of the ideals behind the mental health reform of the 19th century. In particular, Major's and Schirmer's Gaustad represents a break with Frederik Holst's ideal of the panoptic institution. Whereas Holst and his architect Christian Heinrich Grosch promoted a radial plan institution based on the type used for penitentiaries, Schirmer and Major designed a modern, pavilion-style hospital with wards placed independently in the landscape.

  6. Polarimetric C-/X-band Synthetic Aperture Radar Observations of Melting Sea Ice in the Canadian Arctic Archipelago

    Science.gov (United States)

    Casey, J. A.; Beckers, J. F.; Brossier, E.; Haas, C.

    2013-12-01

    Operational ice information services rely heavily on space-borne synthetic aperture radar (SAR) data for the production of ice charts to meet their mandate of providing timely and accurate sea ice information to support safe and efficient marine operations. During the summer melt period, the usefulness of SAR data for sea ice monitoring is limited by the presence of wet snow and melt ponds on the ice surface, which can mask the signature of the underlying ice. This is a critical concern for ice services whose clients (e.g. commercial shipping, cruise tourism, resource exploration and extraction) are most active at this time of year when sea ice is at its minimum extent, concentration and thickness. As a result, there is a need to further quantify the loss of ice information in SAR data during the melt season and to identify what information can still be retrieved about ice surface conditions and melt pond evolution at this time of year. To date the majority of studies have been limited to analysis of single-polarization C-band SAR data. This study will investigate the potential complimentary and unique sea ice information that polarimetric C- and X-band SAR data can provide to supplement the information available from traditional single co-polarized C-band SAR data. A time-series of polarimetric C- and X-band SAR data was acquired over Jones Sound in the Canadian Arctic Archipelago, in the vicinity of the Grise Fiord, Nunavut. Five RADARSAT-2 Wide Fine Quad-pol images and 11 TerraSAR-X StripMap dual-pol (HH/VV) images were acquired. The time-series begins at the onset of melt in early June and extends through advanced melt conditions in late July. Over this period several ponding and drainage events and two snowfall events occurred. Field observations of sea ice properties were collected using an Ice Mass Balance (IMB) buoy, hourly photos from a time-lapse camera deployed on a coastal cliff, and manual in situ measurements of snow thickness and melt pond depth

  7. Band-type microelectrodes for amperometric immunoassays

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ga-Yeon; Chang, Young Wook; Ko, Hyuk [Department of Materials Science and Engineering, Yonsei University, 134 Shinchon-dong, Seodaemun-gu, Seoul, 120-749 (Korea, Republic of); Kang, Min-Jung [Korea Institute of Science and Technology (KIST), Seoul (Korea, Republic of); Pyun, Jae-Chul, E-mail: jcpyun@yonsei.ac.kr [Department of Materials Science and Engineering, Yonsei University, 134 Shinchon-dong, Seodaemun-gu, Seoul, 120-749 (Korea, Republic of)

    2016-07-20

    A band-type microelectrode was made using a parylene-N film as a passivation layer. A circular-type, mm-scale electrode with the same diameter as the band-type microelectrode was also made with an electrode area that was 5000 times larger than the band-type microelectrode. By comparing the amperometric signals of 3,5,3′,5′-tetramethylbenzidine (TMB) samples at different optical density (OD) values, the band-type microelectrode was determined to be 9 times more sensitive than the circular-type electrode. The properties of the circular-type and the band-type electrodes (e.g., the shape of their cyclic voltammograms, the type of diffusion layer used, and the diffusion layer thickness per unit electrode area) were characterized according to their electrode area using the COMSOL Multiphysics software. From these simulations, the band-type electrode was estimated to have the conventional microelectrode properties, even when the electrode area was 100 times larger than a conventional circular-type electrode. These results show that both the geometry and the area of an electrode can influence the properties of the electrode. Finally, amperometric analysis based on a band-type electrode was applied to commercial ELISA kits to analyze human hepatitis B surface antigen (hHBsAg) and human immunodeficiency virus (HIV) antibodies. - Highlights: • A band-type microelectrode was made using a parylene-N film as a passivation layer. • The band-type microelectrode was 14-times more sensitive than circular-type electrode. • The influence of geometry on microelectrode properties was simulated using COMSOL. • The band-type electrode was applied to ELISA kits for hHBsAg and hHIV-antibodies.

  8. Major international sport profiles.

    Science.gov (United States)

    Patel, Dilip R; Stier, Bernhard; Luckstead, Eugene F

    2002-08-01

    Sports are part of the sociocultural fabric of all countries. Although different sports have their origins in different countries, many sports are now played worldwide. International sporting events bring athletes of many cultures together and provide the opportunity not only for athletic competition but also for sociocultural exchange and understanding among people. This article reviews five major sports with international appeal and participation: cricket, martial arts, field hockey, soccer, and tennis. For each sport, the major aspects of physiological and biomechanical demands, injuries, and prevention strategies are reviewed.

  9. Single VDTA Based Dual Mode Single Input Multioutput Biquad Filter

    Directory of Open Access Journals (Sweden)

    Rajeshwari Pandey

    2016-01-01

    Full Text Available This paper presents a dual mode, single input multioutput (SIMO biquad filter configuration using single voltage differencing transconductance amplifier (VDTA, three capacitors, and a grounded resistor. The proposed topology can be used to synthesize low pass (LP, high pass (HP, and band pass (BP filter functions. It can be configured as voltage mode (VM or current mode (CM structure with appropriate input excitation choice. The angular frequency (ω0 of the proposed structure can be controlled independently of quality factor (Q0. Workability of the proposed biquad configuration is demonstrated through PSPICE simulations using 0.18 μm TSMC CMOS process parameters.

  10. Shuttle orbiter Ku-band radar/communications system design evaluation. Deliverable test equipment evaluation

    Science.gov (United States)

    Maronde, R. G.

    1980-07-01

    The Ku-band test equipment, known as the Deliverable System Test equipment (DSTE), is reviewed and evaluated. The DSTE is semiautomated and computer programs were generated for 14 communication mode tests and 17 radar mode tests. The 31 test modules provide a good cross section of tests with which to exercise the Ku-band system; however, it is very limited when being used to verify Ku-band system performance. More detailed test descriptions are needed, and a major area of concern is the DSTE sell-off procedure which is inadequate.

  11. Resonant interaction of a single atom with single photons from a down-conversion source

    Science.gov (United States)

    Schuck, C.; Rohde, F.; Piro, N.; Almendros, M.; Huwer, J.; Mitchell, M. W.; Hennrich, M.; Haase, A.; Dubin, F.; Eschner, J.

    2010-01-01

    We observe the interaction of a single trapped calcium ion with single photons produced by a narrow-band, resonant down-conversion source [A. Haase , Opt. Lett. 34, 55 (2009)], employing a quantum jump scheme. Using the temperature dependence of the down-conversion spectrum and the tunability of the narrow source, absorption of the down-conversion photons is quantitatively characterized.

  12. Characterization of a major 31-kilodalton peptidoglycan-bound protein of Legionella pneumophila

    International Nuclear Information System (INIS)

    Butler, C.A.; Hoffman, P.S.

    1990-01-01

    A 31-kilodalton (kDa) protein was solubilized from the peptidoglycan (PG) fraction of Legionella pneumophila after treatment with either N-acetylmuramidase from the fungus Chalaropsis sp. or with mutanolysin from Streptomyces globisporus. The protein exhibited a ladderlike banding pattern by autoradiography when radiolabeled [(35S]cysteine or [35S]methionine) PG material was extensively treated with hen lysozyme. The banding patterns ranging between 31 and 45 kDa and between 55 and 60 kDa resolved as a single 31-kDa protein when the material was subsequently treated with N-acetylmuramidase. Analysis of the purified 31-kDa protein for diaminopimelic acid by gas chromatography revealed 1 mol of diaminopimelic acid per mol of protein. When outer membrane PG material containing the major outer membrane porin protein was treated with N-acetylmuramidase or mutanolysin, both the 28.5-kDa major outer membrane protein and the 31-kDa protein were solubilized from the PG material under reducing conditions. In the absence of 2-mercaptoethanol, a high-molecular-mass complex (100 kDa) was resolved. The results of this study indicate that a 31-kDa PG-bound protein is a major component of the cell wall of L. pneumophila whose function may be to anchor the major outer membrane protein to PG. Finally, a survey of other Legionella species and other serogroups of L. pneumophila suggested that PG-bound proteins may be a common feature of this genus

  13. Prehabilitation Before Major Surgery

    OpenAIRE

    Johnson Francis

    2018-01-01

    Prehabilitation is a new term for preoperative rehabilitation before major surgery. Some authors use the short form 'Prehab', though it is not so widely used. Prehabilitation involves measures to improve the physical, physiological, metabolic and psychosocial reserves in preparation for an elective surgery. This involves exercise, nutrition, education and psychosocial interventions.

  14. Major New Initiatives

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Major New Initiatives. Multi-party multi-rate video conferencing OOPS. Live Lecture OOPS. Rural ATM Machine Vortex. Finger print detection HP-IITM. Medical Diagnostic kit NeuroSynaptic. LCD projection system TeNeT. Web Terminal MeTeL Midas. Entertainment ...

  15. Solar cell structure incorporating a novel single crystal silicon material

    Science.gov (United States)

    Pankove, Jacques I.; Wu, Chung P.

    1983-01-01

    A novel hydrogen rich single crystal silicon material having a band gap energy greater than 1.1 eV can be fabricated by forming an amorphous region of graded crystallinity in a body of single crystalline silicon and thereafter contacting the region with atomic hydrogen followed by pulsed laser annealing at a sufficient power and for a sufficient duration to recrystallize the region into single crystal silicon without out-gassing the hydrogen. The new material can be used to fabricate semiconductor devices such as single crystal silicon solar cells with surface window regions having a greater band gap energy than that of single crystal silicon without hydrogen.

  16. Realization of an X-Band RF System for LCLS

    CERN Document Server

    McIntosh, Peter; Brooks, William; Emma, Paul; Rago, Carl

    2005-01-01

    A single X-band (11.424 GHz) accelerating structure is to be incorporated in the LCLS Linac design to linearize the energy-time correlation (or gradient) across each bunch, features which originate in the preceding accelerating structures (L0 and L1). This harmonic RF system will operate near the negative RF crest to decelerate the beam, reducing these non-linear components of the correlation, providing a more efficient compression in the downstream bunch compressor chicanes (BC1 and BC2). These non-linear correlation components, if allowed to grow, would lead to Coherent Synchrotron Radiation (CSR) instabilities in the chicanes, effectively destroying the coherence of the photon radiation in the main LCLS undulator. The many years devoted at SLAC in the development of X-band RF components for the NLC/JLC linear collider project, has enabled the technical and financial realization of such an RF system for LCLS. This paper details the requirements for the X-band system and the proposed scheme planned for achie...

  17. Electron correlations in narrow energy bands: modified polar model approach

    Directory of Open Access Journals (Sweden)

    L. Didukh

    2008-09-01

    Full Text Available The electron correlations in narrow energy bands are examined within the framework of the modified form of polar model. This model permits to analyze the effect of strong Coulomb correlation, inter-atomic exchange and correlated hopping of electrons and explain some peculiarities of the properties of narrow-band materials, namely the metal-insulator transition with an increase of temperature, nonlinear concentration dependence of Curie temperature and peculiarities of transport properties of electronic subsystem. Using a variant of generalized Hartree-Fock approximation, the single-electron Green's function and quasi-particle energy spectrum of the model are calculated. Metal-insulator transition with the change of temperature is investigated in a system with correlated hopping. Processes of ferromagnetic ordering stabilization in the system with various forms of electronic DOS are studied. The static conductivity and effective spin-dependent masses of current carriers are calculated as a function of electron concentration at various DOS forms. The correlated hopping is shown to cause the electron-hole asymmetry of transport and ferromagnetic properties of narrow band materials.

  18. Photonic band gap materials: design, synthesis, and applications

    International Nuclear Information System (INIS)

    John, S.

    2000-01-01

    Full text: Unlike semiconductors which facilitate the coherent propagation of electrons, photonic band gap (PBG) materials execute their novel functions through the coherent localization of photons. I review and discuss our recent synthesis of a large scale three-dimensional silicon photonic crystal with a complete photonic band gap near 1.5 microns. When a PBG material is doped with impurity atoms which have an electronic transition that lies within the gap, spontaneous emission of light from the atom is inhibited. Inside the gap, the photon forms a bound state to the atom. Outside the gap, radiative dynamics in the colored vacuum is highly non Markovian. I discuss the influence of these memory effects on laser action. When spontaneous emission is absent, the next order radiative effect (resonance dipole dipole interaction between atoms) must be incorporated leading to anomalous nonlinear optical effects which occur at a much lower threshold than in ordinary vacuum. I describe the collective switching of two-level atoms near a photonic band edge, by external laser field, from a passive state to one exhibiting population inversion. This effect is forbidden in ordinary vacuum. However, in the context of a PBG material, this effect may be utilized for an all-optical transistor. Finally, I discuss the prospects for a phase sensitive, single atom quantum memory device, onto which information may be written by an external laser pulse

  19. Design of Ka-band antipodal finline mixer and detector

    International Nuclear Information System (INIS)

    Yao Changfei; Xu Jinping; Chen Mo

    2009-01-01

    This paper mainly discusses the analysis and design of a finline single-ended mixer and detector. In the circuit, for the purpose of eliminating high-order resonant modes and improving transition loss, metallic via holes are implemented along the mounting edge of the substrate embedded in the split-block of the WG-finline-microstrip transition. Meanwhile, a Ka band slow-wave and bandstop filter, which represents a reactive termination, is designed for the utilization of idle frequencies and operation frequencies energy. Full-wave analysis is carried out to optimize the input matching network of the mixer and the detector circuit using lumped elements to model the nonlinear diode. The exported S-matrix of the optimized circuit is used for conversion loss and voltage sensitivity analysis. The lowest measured conversion loss is 3.52 dB at 32.2 GHz; the conversion loss is flat and less than 5.68 dB in the frequency band of 29-34 GHz. The highest measured zero-bias voltage sensitivity is 1450 mV/mW at 38.6 GHz, and the sensitivity is better than 1000 mV/mW in the frequency band of 38-40 GHz.

  20. AN HI STUDY OF URSA-MAJOR SPIRALS

    NARCIS (Netherlands)

    VERHEIJEN, MAW

    1995-01-01

    This is a progress report on a survey of detailed HI synthesis observations of galaxies in the Ursa Major cluster. Two preliminary conclusions are presented. First, the scatter in the H band Tully-Fisher relation can be reduced by using the maximum rotational velocity taken from the rotation curves.

  1. Major SSC tunneling begins

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    In Texas, work has been completed on the first on the Superconducting Supercollider's major shafts. Now a boring machine has started driving the fifty-four mile elliptical accelerator tunnel. To date, contracts let for the tunnel have come in far below preliminary estimates. Five of the main fourteen foot diameter tunnel contracts have been awarded for a total of 107.4 million dollars, about forty million dollars below estimates. These contracts represent %60 percent of the total tunneling project

  2. An analysis of collegiate band directors' exposure to sound pressure levels

    Science.gov (United States)

    Roebuck, Nikole Moore

    Noise-induced hearing loss (NIHL) is a significant but unfortunate common occupational hazard. The purpose of the current study was to measure the magnitude of sound pressure levels generated within a collegiate band room and determine if those sound pressure levels are of a magnitude that exceeds the policy standards and recommendations of the Occupational Safety and Health Administration (OSHA), and the National Institute of Occupational Safety and Health (NIOSH). In addition, reverberation times were measured and analyzed in order to determine the appropriateness of acoustical conditions for the band rehearsal environment. Sound pressure measurements were taken from the rehearsal of seven collegiate marching bands. Single sample t test were conducted to compare the sound pressure levels of all bands to the noise exposure standards of OSHA and NIOSH. Multiple regression analysis were conducted and analyzed in order to determine the effect of the band room's conditions on the sound pressure levels and reverberation times. Time weighted averages (TWA), noise percentage doses, and peak levels were also collected. The mean Leq for all band directors was 90.5 dBA. The total accumulated noise percentage dose for all band directors was 77.6% of the maximum allowable daily noise dose under the OSHA standard. The total calculated TWA for all band directors was 88.2% of the maximum allowable daily noise dose under the OSHA standard. The total accumulated noise percentage dose for all band directors was 152.1% of the maximum allowable daily noise dose under the NIOSH standards, and the total calculated TWA for all band directors was 93dBA of the maximum allowable daily noise dose under the NIOSH standard. Multiple regression analysis revealed that the room volume, the level of acoustical treatment and the mean room reverberation time predicted 80% of the variance in sound pressure levels in this study.

  3. A GPU-Based Wide-Band Radio Spectrometer

    Science.gov (United States)

    Chennamangalam, Jayanth; Scott, Simon; Jones, Glenn; Chen, Hong; Ford, John; Kepley, Amanda; Lorimer, D. R.; Nie, Jun; Prestage, Richard; Roshi, D. Anish; Wagner, Mark; Werthimer, Dan

    2014-12-01

    The graphics processing unit has become an integral part of astronomical instrumentation, enabling high-performance online data reduction and accelerated online signal processing. In this paper, we describe a wide-band reconfigurable spectrometer built using an off-the-shelf graphics processing unit card. This spectrometer, when configured as a polyphase filter bank, supports a dual-polarisation bandwidth of up to 1.1 GHz (or a single-polarisation bandwidth of up to 2.2 GHz) on the latest generation of graphics processing units. On the other hand, when configured as a direct fast Fourier transform, the spectrometer supports a dual-polarisation bandwidth of up to 1.4 GHz (or a single-polarisation bandwidth of up to 2.8 GHz).

  4. Simulating Precambrian banded iron formation diagenesis

    DEFF Research Database (Denmark)

    Posth, Nicole R.; K??hler, Inga; D. Swanner, Elizabeth

    2013-01-01

    Post-depositional diagenetic alteration makes the accurate interpretation of key precipitation processes in ancient sediments, such as Precambrian banded iron formations (BIFs), difficult. While microorganisms are proposed as key contributors to BIF deposition, the diagenetic transformation...

  5. Experimental study on the adiabatic shear bands

    International Nuclear Information System (INIS)

    Affouard, J.

    1984-07-01

    Four martensitic steels (Z50CDV5 steel, 28CND8 steel, 35NCDV16 steel and 4340 steel) with different hardness between 190 and 600 Hsub(B) (Brinell hardness), have been studied by means of dynamic compressive tests on split Hopkinson pressure bar. Microscopic observations show that the fracture are associated to the development of adiabatic shear bands (except 4340 steel with 190 Hsub(B) hardness). By means of tests for which the deformation is stopped at predetermined levels, the measurement of shear and hardness inside the band and the matrix indicates the chronology of this phenomenon: first the localization of shear, followed by the formation of adiabatic shear band and ultimatly crack initiation and propagation. These results correlated with few simulations by finite elements have permitted to suggest two mecanisms of deformation leading to the formation of adiabatic shear bands in this specific test [fr

  6. Microbiological processes in banded iron formation deposition

    DEFF Research Database (Denmark)

    Posth, Nicole R.; Konhauser, Kurt O.; Kappler, Andreas

    2013-01-01

    Banded iron formations have been studied for decades, particularly regarding their potential as archives of the Precambrian environment. In spite of this effort, the mechanism of their deposition and, specifically, the role that microbes played in the precipitation of banded iron formation minerals......, remains unresolved. Evidence of an anoxic Earth with only localized oxic areas until the Great Oxidation Event ca 2·45 to 2·32 Ga makes the investigation of O2-independent mechanisms for banded iron formation deposition relevant. Recent studies have explored the long-standing proposition that Archean...... banded iron formations may have been formed, and diagenetically modified, by anaerobic microbial metabolisms. These efforts encompass a wide array of approaches including isotope, ecophysiological and phylogeny studies, molecular and mineral marker analysis, and sedimentological reconstructions. Herein...

  7. Deployable Ka-Band Reflectarray, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Tyvak, in collaboration with UCLA, proposes a novel approach to the challenge of creating a large reflector for Ka-band high data rate links. We propose to attach...

  8. Full L-S Band Telemetry System

    National Research Council Canada - National Science Library

    Jensen, Michael

    2001-01-01

    Recent changes in spectrum availability as well as higher demands for spectrum have motivated the development of telemetry transmit systems capable of fully operating over both L and S telemetry bands...

  9. Full L-S Band Telemetry System

    National Research Council Canada - National Science Library

    Jensen, Michael

    2003-01-01

    Recent changes in spectrum availability as well as higher demands for spectrum have motivated the development of telemetry transmit systems capable of fully operating over both L and S telemetry bands...

  10. Full L-S Band Telemetry System

    National Research Council Canada - National Science Library

    Jensen, Michael

    2002-01-01

    Recent changes in spectrum availability as well as higher demands for spectrum have motivated the development of telemetry transmit systems capable of fully operating over both L and S telemetry bands...

  11. Confidence bands for inverse regression models

    International Nuclear Information System (INIS)

    Birke, Melanie; Bissantz, Nicolai; Holzmann, Hajo

    2010-01-01

    We construct uniform confidence bands for the regression function in inverse, homoscedastic regression models with convolution-type operators. Here, the convolution is between two non-periodic functions on the whole real line rather than between two periodic functions on a compact interval, since the former situation arguably arises more often in applications. First, following Bickel and Rosenblatt (1973 Ann. Stat. 1 1071–95) we construct asymptotic confidence bands which are based on strong approximations and on a limit theorem for the supremum of a stationary Gaussian process. Further, we propose bootstrap confidence bands based on the residual bootstrap and prove consistency of the bootstrap procedure. A simulation study shows that the bootstrap confidence bands perform reasonably well for moderate sample sizes. Finally, we apply our method to data from a gel electrophoresis experiment with genetically engineered neuronal receptor subunits incubated with rat brain extract

  12. Free space optical networks for ultra-broad band services

    CERN Document Server

    Kartalopoulos, Stamatios V

    2011-01-01

    "Free Space Optical Network is a next generation communication network which uses optical waves instead of microwaves, potentially offering faster communication with ultra band width, meaning more complex communication services can be simultaneously offered. This book describes the network concepts in simple language starting with point-to-point free space optics basics and discusses networking, interoperability with existing communication network, and security. An ideal resource for communication professionals just entering the free space optical communication field and graduate students majoring in optical communications"--Provided by publisher.

  13. Intraluminal penetration of the band in patients with adjustable silicone gastric banding: radiological findings

    Energy Technology Data Exchange (ETDEWEB)

    Pretolesi, F.; Derchi, L.E. [Cattedra di Radiologia R, Univ. di Genova (Italy); Camerini, G.; Gianetta, E.; Marinari, G.M.; Scopinaro, N. [Semeiotica Chirurgica R, Univ. di Genova (Italy)

    2001-03-01

    The aim of this study was to analyse radiological findings in patients surgically treated for adjustable silicone gastric banding (ASGB) for morbid obesity complicated by band penetration into the gastric lumen. We reviewed the records of four patients with surgically confirmed penetration of gastric band into the gastric lumen; three had preoperative opaque meal, one only a plain abdominal film. Vomiting was the presenting symptom in two cases, whereas others had new weight gain and loss of early satiety. Two patients had normally closed bands: radiography showed that their position had changed from previous controls and the barium meal had passed out of their lumen. Two patients had an open band. One patient had the band at the duodeno-jejunal junction, and the tube connecting the band to the subcutaneous port presented a winding course suggesting the duodenum. In the other case, both plain film and barium studies failed to demonstrate with certainty the intragastric position of the band. As ASGB is becoming widely used, radiologists need to be familiar with its appearances and its complications. Band penetration into the stomach is a serious complication which needs band removal. Patients with this problem, often with non-specific symptoms and even those who are asymptomatic, are encountered during radiographic examinations requested either for gastric problems or follow-up purposes, and have to be properly diagnosed. (orig.)

  14. C-band Scatterometers and Their Applications

    OpenAIRE

    Naeimi, Vahid; Wagner, Wolfgang

    2010-01-01

    C-band scatterometers have demonstrated to be valuable sensors for large-scale observation of the Earth's surface in a variety of disciplines. High temporal sampling in all weather conditions, multi-viewing capability and availability of long-term measurements make the European C-band scatterometers excellent Earth observation tools. Scatterometer data are used to extract geophysical parameters such as wind speed and direction, surface soil moisture, seasonal dynamics of vegetation, spatial a...

  15. C-H Hot Bands in the Near-IR Emission Spectra of Leonids

    Science.gov (United States)

    Freund, F. T.; Scoville, J.; Holm, R.; Seelemann, R.; Freund, M. M.

    2002-01-01

    The reported infrared (IR) emission spectra from 1999 Leonid fireballs show a 3.4 micron C-H emission band and unidentified bands at longer wavelengths. Upon atmospheric entry, the Leonid meteorites were flash-heated to temperatures around 2400K, which would destroy any organics on the surface of the meteorite grains. We propose that the nu(sub )CH emission band in the Leonid emission spectra arises from matrix-embedded C(sub n)-H-O entities that are protected from instant pyrolysis. Our model is based on IR absorption nu(sub )CH bands, which we observed in laboratory-grown MgO and natural olivine single crystals, where they arise from C(sub n)-H-O units imbedded in the mineral matrix, indicative of aliphatic -CH2- and -CH3 organics. Instead of being pyrolyzed, the C(sub n)-H-O entities in the Leonid trails become vibrationally excited to higher levels n = 1, 2, 3 etc. During de-excitation they emit at 3.4 microns, due to the (0 => 1) transition, and at longer wavelengths, due to hot bands. As a first step toward verifying this hypothesis we measured the C-H vibrational manifold of hexane (C6H14). The calculated positions of the (2 => l ) , (3 => 2), and possibly (4 => 3) hot bands agree with the Leonid emission bands at 3.5, 3.8 and 4.l microns.

  16. Fluctuations in a superconducting quantum critical point of multi-band metals

    Energy Technology Data Exchange (ETDEWEB)

    Ramires, A [Instituto de Fisica, Universidade Federal Fluminense, Campus da Praia Vermelha, Niteroi, RJ, 24.210-340 (Brazil); Continentino, M A, E-mail: mucio@cbpf.br [Centro Brasileiro de Pesquisas Fisicas, Rua Dr Xavier Sigaud 150, 22290-180, Rio de Janeiro, RJ (Brazil)

    2011-03-30

    In multi-band metals quasi-particles arising from different atomic orbitals coexist at a common Fermi surface. Superconductivity in these materials may appear due to interactions within a band (intra-band) or among the distinct metallic bands (inter-band). Here we consider the suppression of superconductivity in the intra-band case due to hybridization. The fluctuations at the superconducting quantum critical point (SQCP) are obtained by calculating the response of the system to a fictitious space- and time-dependent field, which couples to the superconducting order parameter. The appearance of superconductivity is related to the divergence of a generalized susceptibility. For a single-band superconductor this coincides with the Thouless criterion. For fixed chemical potential and large hybridization, the superconducting state has many features in common with breached pair superconductivity with unpaired electrons at the Fermi surface. The T = 0 phase transition from the superconductor to the normal state is in the universality class of the density-driven Bose-Einstein condensation. For a fixed number of particles and in the strong coupling limit, the system still has an instability to the normal state with increasing hybridization.

  17. RRI-GBT MULTI-BAND RECEIVER: MOTIVATION, DESIGN, AND DEVELOPMENT

    International Nuclear Information System (INIS)

    Maan, Yogesh; Deshpande, Avinash A.; Chandrashekar, Vinutha; Chennamangalam, Jayanth; Rao, K. B. Raghavendra; Somashekar, R.; Ezhilarasi, M. S.; Sujatha, S.; Kasturi, S.; Sandhya, P.; Duraichelvan, R.; Amiri, Shahram; Aswathappa, H. A.; Sarabagopalan, G.; Ananda, H. M.; Anderson, Gary; Bauserman, Jonah; Beaudet, Carla; Bloss, Marty; Barve, Indrajit V.

    2013-01-01

    We report the design and development of a self-contained multi-band receiver (MBR) system, intended for use with a single large aperture to facilitate sensitive and high time-resolution observations simultaneously in 10 discrete frequency bands sampling a wide spectral span (100-1500 MHz) in a nearly log-periodic fashion. The development of this system was primarily motivated by need for tomographic studies of pulsar polar emission regions. Although the system design is optimized for the primary goal, it is also suited for several other interesting astronomical investigations. The system consists of a dual-polarization multi-band feed (with discrete responses corresponding to the 10 bands pre-selected as relatively radio frequency interference free), a common wide-band radio frequency front-end, and independent back-end receiver chains for the 10 individual sub-bands. The raw voltage time sequences corresponding to 16 MHz bandwidth each for the two linear polarization channels and the 10 bands are recorded at the Nyquist rate simultaneously. We present the preliminary results from the tests and pulsar observations carried out with the Robert C. Byrd Green Bank Telescope using this receiver. The system performance implied by these results and possible improvements are also briefly discussed.

  18. Compact triple band-stop filter using novel epsilon-shaped metamaterial with lumped capacitor

    Science.gov (United States)

    Ali, W. A. E.; Hamdalla, M. Z. M.

    2018-04-01

    This paper presents the design of a novel epsilon-shaped metamaterial unit cell structure that is applicable for single-band and multi-band applications. A closed-form formulas to control the resonance frequencies of the proposed design are included. The proposed unit cell, which exhibits negative permeability at its frequency bands, is etched from the ground plane to form a band-stop filter. The filter design is constructed to validate the band-notched characteristics of the proposed unit cell. A lumped capacitor is inserted for size reduction purpose in addition to multi-resonance generation. The fundamental resonance frequency is translated from 3.62 GHz to 2.45 GHz, which means that the filter size will be more compact (more than 32% size reduction). The overall size of the proposed filter is 13 × 6 × 1.524 mm3, where the electrical size is 0.221λg × 0.102λg × 0.026λg at the lower frequency band (2.45 GHz). Two other resonance frequencies are generated at 5.3 GHz and 9.2 GHz, which confirm the multi-band behavior of the proposed filter. Good agreement between simulated and measured characteristics of the fabricated filter prototype is achieved.

  19. CALIBRATING STELLAR VELOCITY DISPERSIONS BASED ON SPATIALLY RESOLVED H-BAND SPECTRA FOR IMPROVING THE MBH-σ* RELATION

    International Nuclear Information System (INIS)

    Kang, Wol-Rang; Woo, Jong-Hak; Park, Daeseong; Schulze, Andreas; Riechers, Dominik A.; Kim, Sang Chul; Smolcic, Vernesa

    2013-01-01

    To calibrate stellar velocity dispersion measurements from optical and near-IR stellar lines, and to improve the black hole mass (M BH )-stellar velocity dispersion (σ * ) relation, we measure σ * based on high-quality H-band spectra for a sample of 31 nearby galaxies, for which dynamical M BH is available in the literature. By comparing velocity dispersions measured from stellar lines in the H-band with those measured from optical stellar lines, we find no significant difference, suggesting that optical and near-IR stellar lines represent the same kinematics and that dust effect is negligible for early-type galaxies. Based on the spatially resolved rotation and velocity dispersion measurements along the major axis of each galaxy, we find that a rotating stellar disk is present for 80% of galaxies in the sample. For galaxies with a rotation component, σ * measured from a single aperture spectrum can vary by up to ∼20%, depending on the size of the adopted extraction aperture. To correct for the rotational broadening, we derive luminosity-weighted σ * within the effective radius of each galaxy, providing uniformly measured velocity dispersions to improve the M BH -σ * relation.

  20. Systematic study of multi-quasiparticle K -isomeric bands in tungsten isotopes by the extended projected shell model

    Science.gov (United States)

    Wu, Xin-Yi; Ghorui, S. K.; Wang, Long-Jun; Sun, Yang; Guidry, Mike; Walker, Philip M.

    2017-06-01

    Background: The interplay between collective and single-particle degrees of freedom is an important structure aspect to study. The nuclei in the A ≈180 mass region are often denoted as good examples to study such problems because these nuclei are known to exhibit many rotational bands based on multi-quasiparticle K isomers. Purpose: A large set of high-quality experimental data on high-K isomeric states in the A ≈180 mass region has accumulated. A systematic description of them is a theoretical challenge as it requires a method going beyond the usual mean field with multi-quasiparticle configurations built in the shell-model basis. The K -isomer data provide an ideal testing ground for theoretical models. Method: The recently extended projected shell model (PSM) by the Pfaffian method is employed with a sufficiently large configuration space including up to 10 quasiparticles. The restoration of rotational symmetry which is broken in the deformed mean field is obtained by means of angular-momentum projection. With axial symmetry in the basis deformation, each multi-quasiparticle state, classified by a K quantum number, represents the major component of a rotational K band. Shell-model diagonalization in such a projected basis defines the K mixing, which is the key ingredient of the present method. Results: Quasiparticle structure and rotational properties of high-K isomers in even-even neutron-rich W-186174 isotopes are described. The rotational evolution of the yrast and near-yrast bands is discussed with successive band crossings. Multi-quasiparticle K isomers and associated rotational bands in each W isotope are studied with detailed quasiparticle configurations given. Electromagnetic transition properties are also studied and the calculated B (E 2 ),B (M 1 ) , and g -factors are compared with experiment if data exist. Conclusions: Many nuclei of the A ≈180 mass region exhibit properties of an axially symmetric shape and K is approximately a good quantum

  1. Ramadan major dietary patterns.

    Science.gov (United States)

    Shadman, Zhaleh; Poorsoltan, Nooshin; Akhoundan, Mahdieh; Larijani, Bagher; Soleymanzadeh, Mozhdeh; Akhgar Zhand, Camelia; Seyed Rohani, Zahra Alsadat; Khoshniat Nikoo, Mohsen

    2014-09-01

    There has been no data on population based dietary patterns during the Ramadan fasting month. The purpose of this study was to detect Ramadan major dietary patterns among those who fast in Tehran. This cross-sectional study included 600 subjects, aged 18-65 with body mass index (BMI) of 18.5-40, who had decided to fast during Ramadan. Anthropometric measurements, usual physical activity level and educational status were collected two weeks before Ramadan. Information on Ramadan dietary intakes was obtained using a food frequency questionnaire and factor analysis was used to identify major dietary patterns. We identified four major dietary patterns: 1) Western-like pattern; high in fast foods, salty snacks, nuts, potato, fish, poultry, chocolates, juices; 2) high cholesterol and high sweet junk food pattern; high in pickles, sweets and condiments, butter and cream, canned fish, visceral meats and eggs; 3) Mediterranean-like pattern; high in vegetables, olive oil, dates, dairy, dried fruits, fruits, red meats, tea and coffee and 4) Ramadan-style pattern; large consumption of Halim, soups, porridges, legumes and whole grains, soft drinks, Zoolbia and Bamieh. Age was positively and inversely associated with Mediterranean-like (P = 0.003; r = 0.17) and Ramadan style (P = 0.1; r = -0.13) dietary pattern, respectively. Pre-Ramadan physical activity level was associated with a Mediterranean-like dietary pattern (P characteristics, which has not yet been identified as a model of dietary pattern. Also, among identified dietary patterns, Mediterranean-like was the healthiest.

  2. A fast-hopping 3-band CMOS frequency synthesizer for MB-OFDM UWB system

    International Nuclear Information System (INIS)

    Zheng Yongzheng; Xia Lingli; Li Weinan; Huang Yumei; Hong Zhiliang

    2009-01-01

    A fast-hopping 3-band (mode 1) multi-band orthogonal frequency division multiplexing ultra-wideband frequency synthesizer is presented. This synthesizer uses two phase-locked loops for generating steady frequencies and one quadrature single-sideband mixer for frequency shifting and quadrature frequency generation. The generated carriers can hop among 3432 MHz, 3960 MHz, and 4488 MHz. Implemented in a 0.13 μm CMOS process, this fully integrated synthesizer consumes 27 mA current from a 1.2 V supply. Measurement shows that the out-of-band spurious tones are below -50 dBc, while the in-band spurious tones are below -34 dBc. The measured hopping time is below 2 ns. The core die area is 1.0 x 1.8 mm 2 .

  3. A fast-hopping 3-band CMOS frequency synthesizer for MB-OFDM UWB system

    Energy Technology Data Exchange (ETDEWEB)

    Zheng Yongzheng; Xia Lingli; Li Weinan; Huang Yumei; Hong Zhiliang, E-mail: yumeihuang@fudan.edu.c [State Key Laboratory of ASIC and System, Fudan University, Shanghai 201203 (China)

    2009-09-15

    A fast-hopping 3-band (mode 1) multi-band orthogonal frequency division multiplexing ultra-wideband frequency synthesizer is presented. This synthesizer uses two phase-locked loops for generating steady frequencies and one quadrature single-sideband mixer for frequency shifting and quadrature frequency generation. The generated carriers can hop among 3432 MHz, 3960 MHz, and 4488 MHz. Implemented in a 0.13 {mu}m CMOS process, this fully integrated synthesizer consumes 27 mA current from a 1.2 V supply. Measurement shows that the out-of-band spurious tones are below -50 dBc, while the in-band spurious tones are below -34 dBc. The measured hopping time is below 2 ns. The core die area is 1.0 x 1.8 mm{sup 2}.

  4. Band Structure and Quantum Confined Stark Effect in InN/GaN superlattices

    DEFF Research Database (Denmark)

    Gorczyca, I.; Suski, T.; Christensen, Niels Egede

    2012-01-01

    N/GaN(0001) superlattices are investigated, and the variation of the band gap with the thicknesses of the well and the barrier is discussed. Superlattices of the form mInN/nGaN with n ≥ m are simulated using band structure calculations in the Local Density Approximation with a semiempirical correction...... for the gap error. The calculated band gap shows a strong decrease with the thickness (m) of the InN well. In superlattices containing a single layer of InN (m = 1) the band gap increases weakly with the GaN barrier thickness n, reaching a saturation value around 2 eV. In superlattices with n = m and n > 5...

  5. Dual-band absorber for multispectral plasmon-enhanced infrared photodetection

    International Nuclear Information System (INIS)

    Yu, Peng; Ashalley, Eric; Wang, Zhiming; Wu, Jiang; Govorov, Alexander

    2016-01-01

    For most of the reported metamaterial absorbers, the peak absorption only occurs at one single wavelength. Here, we investigated a dual-band absorber which is based on simple gold nano-rings. Two absorption peaks can be readily achieved in 3–5 µ m and 8–14 µ m via tuning the width and radius of gold nano-rings and dielectric constant. The average maximum absorption of two bands can be as high as 95.1% (−0.22 dB). Based on the simulation results, the perfect absorber with nano-rings demonstrates great flexibility to create dual-band or triple-band absorption, and thus holds potential for further applications in thermophotovoltaics, multicolor infrared focal plane arrays, optical filters, and biological sensing applications. (paper)

  6. Shifts and Splittings of the Hole Bands in the Nematic Phase of FeSe

    Science.gov (United States)

    Watson, Matthew D.; Haghighirad, Amir A.; Takita, Hitoshi; Mansuer, Wumiti; Iwasawa, Hideaki; Schwier, Eike F.; Ino, Akihiro; Hoesch, Moritz

    2017-05-01

    We report a high-resolution laser-based angle-resolved photoemission spectroscopy (laser-ARPES) study of single crystals of FeSe, focusing on the temperature-dependence of the hole-like bands around the Γ point. As the system cools through the tetragonal-orthorhombic "nematic" structural transition at 90 K, the splitting of the dxz/dyz bands is observed to increase by a magnitude of 13 meV. Moreover, the onset of a ˜10 meV downward shift of the dxy band is also observed at 90 K. These measurements provide clarity on the nature, magnitude and temperature-dependence of the band shifts at the Γ point in the nematic phase of FeSe.

  7. The Ursa Major supercluster

    International Nuclear Information System (INIS)

    Schuch, N.J.

    1983-01-01

    An optical and a radio survey have been carried out. The optical observations consist of a spectroscopic survey in which redshift data for cluster galaxies and optical identifications of radio sources were obtained with the 98-inch Isaac Newton telescope at the Royal Greenwich Observatory, and the 200-inch Hale telescope; the photographic survey in B, V and R colors was made with the 48-inch Schmidt telescope at Palomar. Some results on the galaxy distribution in the Ursa Major supercluster are briefly discussed. (Auth.)

  8. Electron correlations in narrow band systems

    International Nuclear Information System (INIS)

    Kishore, R.

    1983-01-01

    The effect of the electron correlations in narrow bands, such as d(f) bands in the transition (rare earth) metals and their compounds and the impurity bands in doped semiconductors is studied. The narrow band systems is described, by the Hubbard Hamiltonian. By proposing a local self-energy for the interacting electron, it is found that the results are exact in both atomic and band limits and reduce to the Hartree Fock results for U/Δ → 0, where U is the intra-atomic Coulomb interaction and Δ is the bandwidth of the noninteracting electrons. For the Lorentzian form of the density of states of the noninteracting electrons, this approximation turns out to be equivalent to the third Hubbard approximation. A simple argument, based on the mean free path obtained from the imaginary part of the self energy, shows how the electron correlations can give rise to a discontinous metal-nonmetal transition as proposed by Mott. The band narrowing and the existence of the satellite below the Fermi energy in Ni, found in photoemission experiments, can also be understood. (Author) [pt

  9. Semiconductor of spinons: from Ising band insulator to orthogonal band insulator.

    Science.gov (United States)

    Farajollahpour, T; Jafari, S A

    2018-01-10

    We use the ionic Hubbard model to study the effects of strong correlations on a two-dimensional semiconductor. The spectral gap in the limit where on-site interactions are zero is set by the staggered ionic potential, while in the strong interaction limit it is set by the Hubbard U. Combining mean field solutions of the slave spin and slave rotor methods, we propose two interesting gapped phases in between: (i) the insulating phase before the Mott phase can be viewed as gapping a non-Fermi liquid state of spinons by the staggered ionic potential. The quasi-particles of underlying spinons are orthogonal to physical electrons, giving rise to the 'ARPES-dark' state where the ARPES gap will be larger than the optical and thermal gap. (ii) The Ising insulator corresponding to ordered phase of the Ising variable is characterized by single-particle excitations whose dispersion is controlled by Ising-like temperature and field dependences. The temperature can be conveniently employed to drive a phase transition between these two insulating phases where Ising exponents become measurable by ARPES and cyclotron resonance. The rare earth monochalcogenide semiconductors where the magneto-resistance is anomalously large can be a candidate system for the Ising band insulator. We argue that the Ising and orthogonal insulating phases require strong enough ionic potential to survive the downward renormalization of the ionic potential caused by Hubbard U.

  10. Semiconductor of spinons: from Ising band insulator to orthogonal band insulator

    Science.gov (United States)

    Farajollahpour, T.; Jafari, S. A.

    2018-01-01

    We use the ionic Hubbard model to study the effects of strong correlations on a two-dimensional semiconductor. The spectral gap in the limit where on-site interactions are zero is set by the staggered ionic potential, while in the strong interaction limit it is set by the Hubbard U. Combining mean field solutions of the slave spin and slave rotor methods, we propose two interesting gapped phases in between: (i) the insulating phase before the Mott phase can be viewed as gapping a non-Fermi liquid state of spinons by the staggered ionic potential. The quasi-particles of underlying spinons are orthogonal to physical electrons, giving rise to the ‘ARPES-dark’ state where the ARPES gap will be larger than the optical and thermal gap. (ii) The Ising insulator corresponding to ordered phase of the Ising variable is characterized by single-particle excitations whose dispersion is controlled by Ising-like temperature and field dependences. The temperature can be conveniently employed to drive a phase transition between these two insulating phases where Ising exponents become measurable by ARPES and cyclotron resonance. The rare earth monochalcogenide semiconductors where the magneto-resistance is anomalously large can be a candidate system for the Ising band insulator. We argue that the Ising and orthogonal insulating phases require strong enough ionic potential to survive the downward renormalization of the ionic potential caused by Hubbard U.

  11. Performance characteristics of a perforated shadow band under clear sky conditions

    Energy Technology Data Exchange (ETDEWEB)

    Brooks, Michael J. [School of Mechanical Engineering, University of KwaZulu-Natal, Durban (South Africa)

    2010-12-15

    A perforated, non-rotating shadow band is described for separating global solar irradiance into its diffuse and direct normal components using a single pyranometer. Whereas shadow bands are normally solid so as to occult the sensor of a pyranometer throughout the day, the proposed band has apertures cut from its circumference to intermittently expose the instrument sensor at preset intervals. Under clear sky conditions the device produces a saw tooth waveform of irradiance data from which it is possible to reconstruct separate global and diffuse curves. The direct normal irradiance may then be calculated giving a complete breakdown of the irradiance curves without need of a second instrument or rotating shadow band. This paper describes the principle of operation of the band and gives a mathematical model of its shading mask based on the results of an optical ray tracing study. An algorithm for processing the data from the perforated band system is described and evaluated. In an extended trial conducted at NREL's Solar Radiation Research Laboratory, the band coupled with a thermally corrected Eppley PSP produced independent curves for diffuse, global and direct normal irradiance with low mean bias errors of 5.6 W/m{sup 2}, 0.3 W/m{sup 2} and -2.6 W/m{sup 2} respectively, relative to collocated reference instruments. Random uncertainties were 9.7 W/m{sup 2} (diffuse), 17.3 W/m{sup 2} (global) and 19.0 W/m{sup 2} (direct). When the data processing algorithm was modified to include the ray trace model of sensor exposure, uncertainties increased only marginally, confirming the effectiveness of the model. Deployment of the perforated band system can potentially increase the accuracy of data from ground stations in predominantly sunny areas where instrumentation is limited to a single pyranometer. (author)

  12. Increased theta band EEG power in sickle cell disease patients

    Directory of Open Access Journals (Sweden)

    Case M

    2017-12-01

    Full Text Available Michelle Case,1 Sina Shirinpour,1 Huishi Zhang,1 Yvonne H Datta,2 Stephen C Nelson,3 Karim T Sadak,4 Kalpna Gupta,2 Bin He1,5 1Department of Biomedical Engineering, 2Department of Medicine, University of Minnesota, 3Pediatric Hematology-Oncology, Children’s Hospitals and Clinics of Minnesota, 4Pediatric Hematology-Oncology, University of Minnesota Masonic Children’s Hospital, 5Institute for Engineering in Medicine, University of Minnesota, Minneapolis, MN, USA Objective: Pain is a major issue in the care of patients with sickle cell disease (SCD. The mechanisms behind pain and the best way to treat it are not well understood. We studied how electroencephalography (EEG is altered in SCD patients. Methods: We recruited 20 SCD patients and compared their resting state EEG to that of 14 healthy controls. EEG power was found across frequency bands using Welch’s method. Electrophysiological source imaging was assessed for each frequency band using the eLORETA algorithm. Results: SCD patients had increased theta power and decreased beta2 power compared to controls. Source localization revealed that areas of greater theta band activity were in areas related to pain processing. Imaging parameters were significantly correlated to emergency department visits, which indicate disease severity and chronic pain intensity. Conclusion: The present results support the pain mechanism referred to as thalamocortical dysrhythmia. This mechanism causes increased theta power in patients. Significance: Our findings show that EEG can be used to quantitatively evaluate differences between controls and SCD patients. Our results show the potential of EEG to differentiate between different levels of pain in an unbiased setting, where specific frequency bands could be used as biomarkers for chronic pain. Keywords: sickle cell disease, electroencephalography, chronic pain, electrophysiological source imaging, thalamocortical dysrhythmia

  13. Double Cortex Syndrome (Subcortical Band Heterotopia): A Case Report.

    Science.gov (United States)

    Momen, Ali Akbar; Momen, Mehdi

    2015-01-01

    Objective Approximately 5-10% of preschool age children are considered developmentally disabled. Brain Magnetic Resonance Imaging (MRI) plays a key role in the diagnostic evaluation in these children. Many congenital or acquired brain anomalies are revealed with MRIs. Although the majority of these abnormalities are sporadic but patients with subcortical band heterotopia or double cortex syndrome have sex-linked inheritance. We are going to present the first case in Iran from Ahvaz city, which was presented with status epilepticus associated with developmental delay and finally diagnosed as double cortex syndrome, because band heterotopia cases especially for continuous or generalized form is rare. A 4.5-year-old developmentally delayed girl was admitted for generalized tonic clonic seizure attack of 1 hr, upward gaze, locked mouth, and urinary incontinence (status epilepticus) in the child neurology ward. She had a history of recurrent seizures that started as febrile seizures since she was 12 months of age and had frequent admissions for having recurrent seizure attacks. She was the only child of consanguineous parents with negative family history of any neurologic problems. She was a product of uneventful term pregnancy, vaginal delivery with a low Apgar score at birth who was admitted for six days in the neonatal ward for hypotonia and cyanosis. At 4.5 years of age, she had HC: 45cm (spike-wave discharges. A brain MRI showed corpus callosal dysplasia, generalized band heterotopia, and polymicrogyria. She was discharged home with oral valproate and regular outpatient follow-ups. In the diagnostic evaluation of developmentally delayed and epileptic children, a brain MRI is strongly recommended for accurate diagnosis of anomalies such as neuronal migration disorders (band heterotopia) and others, because appropriate therapeutic management, prognosis, prevention, and genetic counseling for prenatal diagnosis are dependent on definite diagnosis of the proband case.

  14. ISM band to U-NII band frequency transverter and method of frequency transversion

    Science.gov (United States)

    Stepp, Jeffrey David [Grandview, MO; Hensley, Dale [Grandview, MO

    2006-09-12

    A frequency transverter (10) and method for enabling bi-frequency dual-directional transfer of digitally encoded data on an RF carrier by translating between a crowded or otherwise undesirable first frequency band, such as the 2.4 GHz ISM band, and a less-crowded or otherwise desirable second frequency band, such as the 5.0 GHz 6.0 GHz U-NII band. In a preferred embodiment, the transverter (10) connects between an existing data radio (11) and its existing antenna (30), and comprises a bandswitch (12); an input RF isolating device (14); a transmuter (16); a converter (18); a dual output local oscillator (20); an output RF isolating device (22); and an antenna (24) tuned to the second frequency band. The bandswitch (12) allows for bypassing the transverter (10), thereby facilitating its use with legacy systems. The transmuter (14) and converter (16) are adapted to convert to and from, respectively, the second frequency band.

  15. Investigation on the Band Gap and Negative Properties of Concentric Ring Acoustic Metamaterial

    Directory of Open Access Journals (Sweden)

    Meng Chen

    2018-01-01

    Full Text Available The acoustic characteristics of 2D single-oscillator, dual-oscillator, and triple-oscillator acoustic metamaterials were investigated based on concentric ring structures using the finite element method. For the single-oscillator, dual-oscillator, and triple-oscillator models investigated here, the dipolar resonances of the scatterer always induce negative effective mass density, preventing waves from propagating in the structure, thus forming the band gap. As the number of oscillators increases, relative movements between the oscillators generate coupling effect; this increases the number of dipolar resonance modes, causes negative effective mass density in more frequency ranges, and increases the number of band gaps. It can be seen that the number of oscillators in the cell is closely related to the number of band gaps due to the coupling effect, when the filling rate is of a certain value.

  16. Effects of band-tails on the subthreshold characteristics of nanowire band-to-band tunneling transistors

    Science.gov (United States)

    Khayer, M. Abul; Lake, Roger K.

    2011-10-01

    High source doping is required to support the high electric fields necessary to provide sufficient drive currents in interband tunnel field effect transistors (TFETs). High doping is associated with band-tails in the density of states that decay exponentially into the bandgap with decay constants that can be comparable to the room temperature thermal energy kBT. This compromises the core operational principal of a TFET of a hard energy cut-off to the injected channel carrier distribution provided by the source valence band edge. If the band-tails are limited to the source region, they have minimal effect for short channels ≤10 nm, since the leakage current is dominated by direct, coherent tunneling through the channel. For longer 20 nm channels, source band-tails can double the inverse subthreshold slope but still leave it below the ideal 60 mV/decade value with on-off current ratios greater than 106 using a supply voltage of 0.4 V. Band-tails both in the source and channel are more detrimental for both 10 and 20 nm channels. On-off current ratios are reduced to ≥103 and ≥104 for the 10 nm and 20 nm channel devices, respectively.

  17. Major Depression Detection from EEG Signals Using Kernel Eigen-Filter-Bank Common Spatial Patterns

    Directory of Open Access Journals (Sweden)

    Shih-Cheng Liao

    2017-06-01

    Full Text Available Major depressive disorder (MDD has become a leading contributor to the global burden of disease; however, there are currently no reliable biological markers or physiological measurements for efficiently and effectively dissecting the heterogeneity of MDD. Here we propose a novel method based on scalp electroencephalography (EEG signals and a robust spectral-spatial EEG feature extractor called kernel eigen-filter-bank common spatial pattern (KEFB-CSP. The KEFB-CSP first filters the multi-channel raw EEG signals into a set of frequency sub-bands covering the range from theta to gamma bands, then spatially transforms the EEG signals of each sub-band from the original sensor space to a new space where the new signals (i.e., CSPs are optimal for the classification between MDD and healthy controls, and finally applies the kernel principal component analysis (kernel PCA to transform the vector containing the CSPs from all frequency sub-bands to a lower-dimensional feature vector called KEFB-CSP. Twelve patients with MDD and twelve healthy controls participated in this study, and from each participant we collected 54 resting-state EEGs of 6 s length (5 min and 24 s in total. Our results show that the proposed KEFB-CSP outperforms other EEG features including the powers of EEG frequency bands, and fractal dimension, which had been widely applied in previous EEG-based depression detection studies. The results also reveal that the 8 electrodes from the temporal areas gave higher accuracies than other scalp areas. The KEFB-CSP was able to achieve an average EEG classification accuracy of 81.23% in single-trial analysis when only the 8-electrode EEGs of the temporal area and a support vector machine (SVM classifier were used. We also designed a voting-based leave-one-participant-out procedure to test the participant-independent individual classification accuracy. The voting-based results show that the mean classification accuracy of about 80% can be

  18. Major Depressive Disorder

    Directory of Open Access Journals (Sweden)

    G Grobler

    2013-08-01

    Full Text Available The treatment guideline draws on several international guidelines: (iPractice Guidelines of the American Psychiatric Association (APAfor the Treatment of Patients with Major Depressive Disorder, SecondEdition;[1](ii Clinical Guidelines for the Treatment of DepressiveDisorders by the Canadian Psychiatric Association and the CanadianNetwork for Mood and Anxiety Treatments (CANMAT;[2](iiiNational Institute for Clinical Excellence (NICE guidelines;[3](iv RoyalAustralian and New Zealand College of Psychiatrists Clinical PracticeGuidelines Team for Depression (RANZCAP;[4](v Texas MedicationAlgorithm Project (TMAP Guidelines;[5](vi World Federation ofSocieties of Biological Psychiatry (WFSBP Treatment Guideline forUnipolar Depressive Disorder;[6]and (vii British Association forPsychopharmacology Guidelines.[7

  19. The decay-out of superdeformed bands in the A = 190 region. What have we learned?

    International Nuclear Information System (INIS)

    Lauritsen, T.; Hackman, G.; Khoo, T.L.; Carpenter, M.P.; Janssens, R.V.F.; Ackermann, D.; Ahmad, I.; Blumenthal, D.J.; Lopez-Martens, A.

    1997-01-01

    One-step decay transitions linking the superdeformed (SD) bands 1 and 3 in 194 Hg to yrast levels are discussed. Inter-band transitions between bands 1 and 3 have also been identified. For the first time, the spin, parity and excitation energy have been determined for two SD bands in the same nucleus. The low excitation energy of the excited band supports the view that it is based on an octupole excitation. It is believed that Porter-Thomas fluctuations play a major role in determining the strength of the one-step transitions as suggested by the fact that only one other SD band has been linked in the A = 190 mass region ( 194 Pb) at the present time. When Porter-Thomas fluctuations prevent the observation of one-step or two-step linking transitions, as e.g. in the case of 192 Hg, the analysis of the quasi-continuous part of the decay-out spectrum provides an alternative method for the determination of the excitation energy and spin of an SD band. This method is discussed in detail. (author)

  20. Reconfigurable/tunable dual band/dual mode ferrite composite right/left-handed CPW coupled-line coupler

    Science.gov (United States)

    Abdalla, M. A.; Hu, Z.

    2017-09-01

    This paper presents the design, modeling and experimental verification of a novel reconfigurable/tunable dual band/dual mode ferrite composite right/left handed CPW coupled-line coupler. The composite right/left handed configuration has been realized by loading coupled CPW transmission lines with series inter-digital capacitors and shunt segment inductors. The coupler performance has been verified using the equivalent circuit model, electromagnetic full wave simulations and experimental measurements. The coupler operates on dual mode in that it has dual bands of operation with two different propagation mechanisms. The first band has only a reciprocal backward coupling whereas the second band has only nonreciprocal through propagation. The non-reciprocity isolation in the second band is better than average of 15 dB. Compared to conventional single band single mode coupled line coupler of length = 0.25 λg, the proposed novel dual band dual mode coupler length is almost the same (0.265 λg) at 4.5 GHz. Furthermore, the dual mode/dual band coupler can have tunable functionality.

  1. Band width and multiple-angle valence-state mapping of diamond

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez, I.; Terminello, L.J.; Sutherland, D.G.J. [Lawrence Berkeley National Lab., CA (United States)] [and others

    1997-04-01

    The band width may be considered the single most important parameter characterizing the electronic structure of a solid. The ratio of band width and Coulomb repulsion determines how correlated or delocalized an electron system is. Some of the most interesting solids straddle the boundary between localized and delocalized, e.g. the high-temperature superconductors. The bulk of the band calculations available today is based on local density functional (DF) theory. Even though the Kohn-Sham eigenvalues from that theory do not represent the outcome of a band-mapping experiment, they are remarkably similar to the bands mapped via photoemission. Strictly speaking, one should use an excited state calculation that takes the solid`s many-body screening response to the hole created in photoemission into account. Diamond is a useful prototype semiconductor because of its low atomic number and large band width, which has made it a long-time favorite for testing band theory. Yet, the two experimental values of the band width of diamond have error bars of {+-}1 eV and differ by 3.2 eV. To obtain an accurate valence band width for diamond, the authors use a band-mapping method that collects momentum distributions instead of the usual energy distributions. This method has undergone extensive experimental and theoretical tests in determining the band width of lithium fluoride. An efficient, imaging photoelectron spectrometer is coupled with a state-of-the-art undulator beam line at the Advanced Light Source to allow collection of a large number of data sets. Since it takes only a few seconds to take a picture of the photoelectrons emitted into a 84{degrees} cone, the authors can use photon energies as high as 350 eV where the cross section for photoemission from the valence band is already quite low, but the emitted photoelectrons behave free-electron-like. This make its much easier to locate the origin of the inter-band transitions in momentum space.

  2. Disorder-induced transition between s± and s++ states in two-band superconductors

    NARCIS (Netherlands)

    Efremov, D.V.; Korshunov, M.M.; Dolgov, O.V.; Golubov, Alexandre Avraamovitch; Hirschfeld, P.J.

    2011-01-01

    We have reexamined the problem of disorder in two-band superconductors, and shown, within the framework of the T-matrix approximation, that the suppression of Tc can be described by a single parameter depending on the intraband and interband impurity scattering rates. Tc is shown to be more robust

  3. Voice-band data modem BER performance via CVSD SCPC satellite circuits

    Science.gov (United States)

    He, Ping J.

    1991-10-01

    This paper describes the test results of the transmission of voice-band modem data at 2400-9600 bits/s via single- and multiple-hop CVSD-SCPC satellite circuits. The BER performances and the optimum ranges of signal level for data transmission by means of two types of 32 kbits/s CVSD systems are presented.

  4. Functionally Graded Thermoelectric Material though One Step Band Gap and Dopant Engineering

    DEFF Research Database (Denmark)

    Jensen, Ellen Marie; Borup, Kasper Andersen; Cederkrantz, Daniel

    gradients. It has previously been shown that a large functionally graded thermoelectric single crystal can be synthesized by the Czochralski method (1). Utilizing element gradients inherent to the Czochralski process we have synthesized a Ge1-xSix:B crystal with a continuously varying x, band gap...

  5. Tunable High-Q N-Path Band-Pass Filters: Modeling and Verification

    NARCIS (Netherlands)

    Ghaffari, A.; Klumperink, Eric A.M.; Soer, M.C.M.; Nauta, Bram

    2011-01-01

    Abstract—A differential single-port switched-RC N-path filter with band-pass characteristic is proposed. The switching frequency defines the center frequency, while the RC-time and duty cycle of the clock define the bandwidth. This allows for high-Q highly tunable filters which can for instance be

  6. Pear responses to split fertigation and band placement of nitrogen and phosphorus

    Science.gov (United States)

    Split fertigation and band placement of N and P may increase the use efficiency of applied N and P compared with the current N and P management practice -- single broadcast application of N and P on the soil surface. A field experiment was conducted from 2005 through 2006 to evaluate the effects of ...

  7. Within-band spray distribution of nozzles used for herbaceous plant control

    Science.gov (United States)

    James H. Miller

    1994-01-01

    Abstract. Described are the spray patterns of nozzles setup for banded herbaceous plant control treatments. Spraying Systems Company nozzles. were tested, but similar nozzles are available from other manufacturers. Desirable traits were considered to be as follows: an even distribution pattern, low volume, low height, large droplets, and a single...

  8. Crosstalk-Managed Heterogeneous Single-Mode 32-Core Fibre

    DEFF Research Database (Denmark)

    Sasaki, Y.; Fukumoto, Ryohei; Takenaga, Katsuhiro

    2016-01-01

    A heterogeneous single-mode 32-core fibre with a cladding diameter of 243 micrometer is designed and fabricated. The highest core count in single-mode multi-core fibres and low worst-case crosstalk of less than -24 dB/1000 km in C-band are achieved simultaneously.......A heterogeneous single-mode 32-core fibre with a cladding diameter of 243 micrometer is designed and fabricated. The highest core count in single-mode multi-core fibres and low worst-case crosstalk of less than -24 dB/1000 km in C-band are achieved simultaneously....

  9. Effect of band gap engineering in anionic-doped TiO2 photocatalyst

    International Nuclear Information System (INIS)

    Samsudin, Emy Marlina; Abd Hamid, Sharifah Bee

    2017-01-01

    Highlights: • Band gap engineering using anion dopants. • Mid band energy level. • Ti 3+ and oxygen vacancies as impurities states. • Valence band tail extension due to doping. • Wider solar light absorption. - Abstract: A simple yet promising strategy to modify TiO 2 band gap was achieved via dopants incorporation which influences the photo-responsiveness of the photocatalyst. The mesoporous TiO 2 was successfully mono-doped and co-doped with nitrogen and fluorine dopants. The results indicate that band gap engineering does not necessarily requires oxygen substitution with nitrogen or/and fluorine, but from the formation of additional mid band and Ti 3+ impurities states. The formation of oxygen vacancies as a result of modified color centres and Ti 3+ ions facilitates solar light absorption and influences the transfer, migration and trapping of the photo-excited charge carriers. The synergy of dopants in co-doped TiO 2 shows better optical properties relative to single N and F doped TiO 2 with c.a 0.95 eV band gap reduction. Evidenced from XPS, the synergy between N and F in the co-doped TiO 2 uplifts the valence band towards the conduction band. However, the photoluminescence data reveals poorer electrons and holes separation as compared to F-doped TiO 2 . This observation suggests that efficient solar light harvesting was achievable via N and F co-doping, but excessive defects could act as charge carriers trapping sites.

  10. Effect of band gap engineering in anionic-doped TiO{sub 2} photocatalyst

    Energy Technology Data Exchange (ETDEWEB)

    Samsudin, Emy Marlina; Abd Hamid, Sharifah Bee, E-mail: sharifahbee@um.edu.my

    2017-01-01

    Highlights: • Band gap engineering using anion dopants. • Mid band energy level. • Ti{sup 3+} and oxygen vacancies as impurities states. • Valence band tail extension due to doping. • Wider solar light absorption. - Abstract: A simple yet promising strategy to modify TiO{sub 2} band gap was achieved via dopants incorporation which influences the photo-responsiveness of the photocatalyst. The mesoporous TiO{sub 2} was successfully mono-doped and co-doped with nitrogen and fluorine dopants. The results indicate that band gap engineering does not necessarily requires oxygen substitution with nitrogen or/and fluorine, but from the formation of additional mid band and Ti{sup 3+} impurities states. The formation of oxygen vacancies as a result of modified color centres and Ti{sup 3+} ions facilitates solar light absorption and influences the transfer, migration and trapping of the photo-excited charge carriers. The synergy of dopants in co-doped TiO{sub 2} shows better optical properties relative to single N and F doped TiO{sub 2} with c.a 0.95 eV band gap reduction. Evidenced from XPS, the synergy between N and F in the co-doped TiO{sub 2} uplifts the valence band towards the conduction band. However, the photoluminescence data reveals poorer electrons and holes separation as compared to F-doped TiO{sub 2}. This observation suggests that efficient solar light harvesting was achievable via N and F co-doping, but excessive defects could act as charge carriers trapping sites.

  11. Spectrum Measurement and Analysis of TV Band in Support of Cognitive Radio Operation in India

    DEFF Research Database (Denmark)

    Patil, Kishor P.; Skouby, Knud Erik; Prasad, Ramjee

    2013-01-01

    TV White Spaces constitutes the major portion of the VHF and UHF TV band which is geographically unused after digital switchover. The most important regulatory trend in the context of Dynamic Spectrum Access (DSA) is the Cognitive access of TV white Spaces. Through spectrum measurement campaign we...... have estimated the spectrum utilization of TV band in Pune, India. We have designed the measurement set up and methodology for the measurement campaign. Our spectrum occupancy analysis provides the realistic view on the spectrum opportunities in India for (i) spectrum refarming of TV band; (ii......) Cognitive Radio operation in TV band. Also we have stressed on the need of quantitative analysis of TVWSs availability and compatibility studies for protection of incumbent services for CR access of TVWSs in India. Also this paper reviews the state-of-the-art in standardization of cognitive access to TVWS....

  12. Single Electron Tunneling

    International Nuclear Information System (INIS)

    Ruggiero, Steven T.

    2005-01-01

    Financial support for this project has led to advances in the science of single-electron phenomena. Our group reported the first observation of the so-called ''Coulomb Staircase'', which was produced by tunneling into ultra-small metal particles. This work showed well-defined tunneling voltage steps of width e/C and height e/RC, demonstrating tunneling quantized on the single-electron level. This work was published in a now well-cited Physical Review Letter. Single-electron physics is now a major sub-field of condensed-matter physics, and fundamental work in the area continues to be conducted by tunneling in ultra-small metal particles. In addition, there are now single-electron transistors that add a controlling gate to modulate the charge on ultra-small photolithographically defined capacitive elements. Single-electron transistors are now at the heart of at least one experimental quantum-computer element, and single-electron transistor pumps may soon be used to define fundamental quantities such as the farad (capacitance) and the ampere (current). Novel computer technology based on single-electron quantum dots is also being developed. In related work, our group played the leading role in the explanation of experimental results observed during the initial phases of tunneling experiments with the high-temperature superconductors. When so-called ''multiple-gap'' tunneling was reported, the phenomenon was correctly identified by our group as single-electron tunneling in small grains in the material. The main focus throughout this project has been to explore single electron phenomena both in traditional tunneling formats of the type metal/insulator/particles/insulator/metal and using scanning tunneling microscopy to probe few-particle systems. This has been done under varying conditions of temperature, applied magnetic field, and with different materials systems. These have included metals, semi-metals, and superconductors. Amongst a number of results, we have

  13. Automated coregistration of MTI spectral bands.

    Energy Technology Data Exchange (ETDEWEB)

    Theiler, J. P. (James P.); Galbraith, A. E. (Amy E.); Pope, P. A. (Paul A.); Ramsey, K. A. (Keri A.); Szymanski, J. J. (John J.)

    2002-01-01

    In the focal plane of a pushbroom imager, a linear array of pixels is scanned across the scene, building up the image one row at a time. For the Multispectral Thermal Imager (MTI), each of fifteen different spectral bands has its own linear array. These arrays are pushed across the scene together, but since each band's array is at a different position on the focal plane, a separate image is produced for each band. The standard MTI data products resample these separate images to a common grid and produce coregistered multispectral image cubes. The coregistration software employs a direct 'dead reckoning' approach. Every pixel in the calibrated image is mapped to an absolute position on the surface of the earth, and these are resampled to produce an undistorted coregistered image of the scene. To do this requires extensive information regarding the satellite position and pointing as a function of time, the precise configuration of the focal plane, and the distortion due to the optics. These must be combined with knowledge about the position and altitude of the target on the rotating ellipsoidal earth. We will discuss the direct approach to MTI coregistration, as well as more recent attempts to 'tweak' the precision of the band-to-band registration using correlations in the imagery itself.

  14. Excited negative parity bands in 160Yb

    Science.gov (United States)

    Saha, A.; Bhattacharjee, T.; Curien, D.; Dedes, I.; Mazurek, K.; Banerjee, S. R.; Rajbanshi, S.; Bisoi, A.; de Angelis, G.; Bhattacharya, Soumik; Bhattacharyya, S.; Biswas, S.; Chakraborty, A.; Das Gupta, S.; Dey, B.; Goswami, A.; Mondal, D.; Pandit, D.; Palit, R.; Roy, T.; Singh, R. P.; Saha Sarkar, M.; Saha, S.; Sethi, J.

    2018-03-01

    Negative parity rotational bands in {} 70160Yb{}90 nucleus have been studied. They were populated in the 148Sm(16O, 4n)160Yb reaction at 90 MeV. The gamma-coincidence data have been collected using Indian National Gamma Array composed of twenty Compton suppressed clover germanium (Ge) detectors. Double gating on triple gamma coincidence data were selectively used to develop the decay scheme for these negative parity bands by identifying and taking care of the multiplet transitions. The even- and odd-spin negative parity bands in 160Yb have been studied by comparing the reduced transition probability ratios with the similar bands in neighbouring even-even rare earth nuclei. It is concluded that the concerned odd-spin and even-spin bands are not signature partners and that their structures are compatible with those of the ‘pear-shape’ and ‘pyramid-shape’ oscillations, respectively, the octupole shapes superposed with the quadrupole shape of the ground-state.

  15. Mesoscopic colonization of a spectral band

    International Nuclear Information System (INIS)

    Bertola, M; Lee, S Y; Mo, M Y

    2009-01-01

    We consider the unitary matrix model in the limit where the size of the matrices becomes infinite and in the critical situation when a new spectral band is about to emerge. In previous works, the number of expected eigenvalues in the neighborhood of the band was fixed and finite, a situation that was termed 'birth of a cut' or 'first colonization'. We now consider the transitional regime where this microscopic population in the new band grows without bounds but at a slower rate than the size of the matrix. The local population in the new band organizes in a 'mesoscopic' regime, in between the macroscopic behavior of the full system and the previously studied microscopic one. The mesoscopic colony may form a finite number of new bands, with a maximum number dictated by the degree of criticality of the original potential. We describe the delicate scaling limit that realizes and controls the mesoscopic colony. The method we use is the steepest descent analysis of the Riemann-Hilbert problem that is satisfied by the associated orthogonal polynomials.

  16. Percutaneous tension band wiring for patellar fractures.

    Science.gov (United States)

    Rathi, Akhilesh; Swamy, M K S; Prasantha, I; Consul, Ashu; Bansal, Abhishek; Bahl, Vibhu

    2012-08-01

    To evaluate outcome of percutaneous tension band wiring for transverse fractures of the patella. 16 men and 7 women aged 27 to 65 (mean, 40) years underwent percutaneous tension band wiring for transverse fractures of the patella with a displacement of >3 mm. Pain, operating time, mobility, functional score, and complications were evaluated. 20 patients underwent successful percutaneous tension band wiring. The remaining 3 patients in whom closed reduction failed underwent open reduction and tension band wiring. The mean operating time was 46 (range, 28-62) minutes. The mean follow-up period was 20 (range, 15-30) months. At the latest follow-up, all patients had regained full extension. The objective score was excellent in 20 patients and good in 3, whereas the subjective score was excellent in 17, good in 5, and fair in one. All patients had radiological union at week 8. One patient had patellofemoral arthritis (secondary to a postoperative articular step). Two patients developed superficial infections, which resolved after antibiotic therapy. Mean thigh muscle wasting was 0.7 (range, 0.4-1) cm. Three patients encountered hardware problems (impingement/irritation of the skin over the knee) necessitating implant removal. Percutaneous tension band wiring is a viable option for transverse fractures of the patella.

  17. Ferritin associates with marginal band microtubules

    International Nuclear Information System (INIS)

    Infante, Anthony A.; Infante, Dzintra; Chan, M.-C.; How, P.-C.; Kutschera, Waltraud; Linhartova, Irena; Muellner, Ernst W.; Wiche, Gerhard; Propst, Friedrich

    2007-01-01

    We characterized chicken erythrocyte and human platelet ferritin by biochemical studies and immunofluorescence. Erythrocyte ferritin was found to be a homopolymer of H-ferritin subunits, resistant to proteinase K digestion, heat stable, and contained iron. In mature chicken erythrocytes and human platelets, ferritin was localized at the marginal band, a ring-shaped peripheral microtubule bundle, and displayed properties of bona fide microtubule-associated proteins such as tau. Red blood cell ferritin association with the marginal band was confirmed by temperature-induced disassembly-reassembly of microtubules. During erythrocyte differentiation, ferritin co-localized with coalescing microtubules during marginal band formation. In addition, ferritin was found in the nuclei of mature erythrocytes, but was not detectable in those of bone marrow erythrocyte precursors. These results suggest that ferritin has a function in marginal band formation and possibly in protection of the marginal band from damaging effects of reactive oxygen species by sequestering iron in the mature erythrocyte. Moreover, our data suggest that ferritin and syncolin, a previously identified erythrocyte microtubule-associated protein, are identical. Nuclear ferritin might contribute to transcriptional silencing or, alternatively, constitute a ferritin reservoir

  18. The dilemma of the wedding band.

    Science.gov (United States)

    Stein, Daniel T; Pankovich-Wargula, Alanna L

    2009-02-01

    The postoperative infection rate in procedures where no ring is worn, and those where a plain metal wedding band is worn under the glove was studied retrospectively. From January 1998 through June 2002, 2127 surgeries were performed by the lead author (D.T.S.), the first 2 years without a wedding band and the next 2 years with a simple platinum wedding band worn under the glove. Attention was paid to sliding the ring proximal and distal on the finger, ensuring scrub solution was under the ring and that the area of skin below the ring was cleansed. Twenty-two postoperative infections were recorded in 2127 surgeries. This is a postoperative infection rate of 1.0%, and wedding ring worn, nor do they demonstrate an increased infection rate with wearing jewelry. This study suggests that there is no correlation between wearing a plain wedding band under the surgical glove and an increase in postoperative infections. The crevices and cuticle of the fingers and nails may provide more significant infection risk than a plain metal wedding band. This is a level III retrospective cohort study.

  19. Band warping, band non-parabolicity, and Dirac points in electronic and lattice structures

    Science.gov (United States)

    Resca, Lorenzo; Mecholsky, Nicholas A.; Pegg, Ian L.

    2017-10-01

    We illustrate at a fundamental level the physical and mathematical origins of band warping and band non-parabolicity in electronic and vibrational structures. We point out a robust presence of pairs of topologically induced Dirac points in a primitive-rectangular lattice using a p-type tight-binding approximation. We analyze two-dimensional primitive-rectangular and square Bravais lattices with implications that are expected to generalize to more complex structures. Band warping is shown to arise at the onset of a singular transition to a crystal lattice with a larger symmetry group, which allows the possibility of irreducible representations of higher dimensions, hence band degeneracy, at special symmetry points in reciprocal space. Band warping is incompatible with a multi-dimensional Taylor series expansion, whereas band non-parabolicities are associated with multi-dimensional Taylor series expansions to all orders. Still band non-parabolicities may merge into band warping at the onset of a larger symmetry group. Remarkably, while still maintaining a clear connection with that merging, band non-parabolicities may produce pairs of conical intersections at relatively low-symmetry points. Apparently, such conical intersections are robustly maintained by global topology requirements, rather than any local symmetry protection. For two p-type tight-binding bands, we find such pairs of conical intersections drifting along the edges of restricted Brillouin zones of primitive-rectangular Bravais lattices as lattice constants vary relatively to each other, until these conical intersections merge into degenerate warped bands at high-symmetry points at the onset of a square lattice. The conical intersections that we found appear to have similar topological characteristics as Dirac points extensively studied in graphene and other topological insulators, even though our conical intersections have none of the symmetry complexity and protection afforded by the latter more

  20. Application of molecular markers for genetic discrimination of Fusarium wilt pathogen races affecting chickpea and pigeonpea in major regions of India.

    Science.gov (United States)

    Datta, J; Lal, N

    2012-12-22

    (foc) and Fusarium udum (Fud) collected from major pulse growing regions of India. Out of 247 bands produced by 24 Randomly Amplified Polymorphic DNA (RAPD) primers in Foc isolates, 210 (85%) were polymorphic. A maximum of 14 amplicons were generated by primer OPF 05 whereas minimum 7 amplicons were generated by primer K7. A total of 24 alleles were produced by twelve Simple Sequence Repeats (SSR) primers with an average of two alleles per marker in foc isolates. The maximum number of 4 alleles was obtained with primer SSR 12. SSR amplicon size ranged from 100 to 400 bp. The Unweighted Pair Group Method with Arithmetic average (UPGMA) cluster analysis based on RAPD and SSR profiles grouped the fourteen foc isolates into four major clusters. The universal Inter Transcribed Spacer (ITS) primer pair amplified 630 bp bands in all fourteen foc isolates while significant length polymorphism was obtained only when analysed by restriction digestion with EcoRI and MspI enzymes. The cluster analysis of ITS—RFLP grouped all 14 Foc isolates into three major clusters. Twenty four RAPD primers generated a total of 226 bands (ranging 0.3 to 3.0 kb) in Fusarium udum with an average of 9.4 bands per primer and a total of 27 alleles were produced by twelve SSR primers with an average of 2.25 alleles per marker. All isolates amplified a single band ranging from 100 to 450 bp. The universal ITS primer pair amplified 650 bp bands in all fourteen fud isolates while significant length polymorphism was obtained only when analysed by restriction digestion with EcoRI and Hind III enzymes. The cluster analysis of ITS—RFLP grouped all 14 Fud isolates into three major clusters. The cluster analysis using various markers show the grouping of Fusarium isolates strictly according to their cultural characteristics and degree of pathogenicity and not the geographical origin. This information will be helpful for pathologists and plant breeders to design effective resistance breeding programs in

  1. Low Complexity Bayesian Single Channel Source Separation

    DEFF Research Database (Denmark)

    Beierholm, Thomas; Pedersen, Brian Dam; Winther, Ole

    2004-01-01

    We propose a simple Bayesian model for performing single channel speech separation using factorized source priors in a sliding window linearly transformed domain. Using a one dimensional mixture of Gaussians to model each band source leads to fast tractable inference for the source signals. Simul...

  2. A one-step conversion from gastric banding to laparoscopic Roux-en-Y gastric bypass is as safe as a two-step conversion: A comparative analysis of 885 patients.

    Science.gov (United States)

    Debergh, Isabelle; Defoort, Barbara; De Visschere, Marieke; Flahou, Silke; Van Cauwenberge, Sebastiaan; Mulier, Jan P; Dillemans, Bruno

    2016-10-01

    To achieve additional weight loss or to resolve band-related problems, a laparoscopic adjustable gastric banding (LAGB) can be converted to a laparoscopic Roux-en-Y gastric bypass (RYGB). There is limited data on the feasibility and safety of routinely performing a single-step conversion. We assessed the efficacy of this revisional approach in a large cohort of patients operated in a high-volume bariatric institution. Between October 2004 and December 2015, a total of 885 patients who underwent LAGB removal with RYGB were identified from a prospectively collected database. In all cases, a single-stage conversion procedure was planned. The feasibility of this approach and peri-operative outcomes of these patients were evaluated and analyzed. A single-step approach was successfully achieved in 738 (83.4%) of the 885 patients. During the study period, there was a significant increase in performing the conversion from LAGB to RYGB single-staged. No mortality or anastomotic leakage was observed in both groups. Only 45 patients (5.1%) had a 30-d complication: most commonly hemorrhage (N = 20/45), with no significant difference between the groups. Converting a LAGB to RYGB can be performed with a very low morbidity and zero-mortality in a high-volume revisional bariatric center. With increasing experience and full standardization of the conversion, the vast majority of operations can be performed as a single-stage procedure. Only a migrated band remains a formal contraindication for a one-step approach.

  3. Design and Fabrication of S-Band Diplexer for LEO TT&C Application

    Directory of Open Access Journals (Sweden)

    Sang-Il Ahn

    2007-12-01

    Full Text Available Diplexer is one of core devices needed to communicate with satellite using single ground antenna by separating uplink and downlink signal. This paper presents the design of the S-band diplexer for LEO TT&C application, especially for KOMPSAT (KOrea Multi-Purpose SATellite. To cope with requirements such as high handling power, low insertion loss, air-cavity resonator with high quality factor was considered as one of design drivers. Design was started with predicting unloaded Q and equivalent circuit from the structure of air-cavity resonator. For the convenience of adjustment, the coupling factor placed between resonators was estimated from COTS EM (Electro-Magnetic simulator, EESOF ADS^{TM}, and expressed with 2-order polynomial regression. To improve the isolation between transmitting part (Tx and receiving part (Rx, the inductive and capacitive attenuation poles were inserted between 4^{th} and 6^{th} resonator respectively. The fabricated diplexer consists of two bandpass filters and each filter has eight resonants. From the measurement, it was shown that major requirements such as 0.5dB of insertion loss, 20dB of return loss and 100dB of isolation were fully satisfied within passband.

  4. Obituary: David L. Band (1957-2009)

    Science.gov (United States)

    Cominsky, Lynn

    2011-12-01

    David L. Band, of Potomac Maryland, died on March 16, 2009 succumbing to a long battle with spinal cord cancer. His death at the age of 52 came as a shock to his many friends and colleagues in the physics and astronomy community. Band showed an early interest and exceptional aptitude for physics, leading to his acceptance at the Massachusetts Institute of Technology as an undergraduate student in 1975. After graduating from MIT with an undergraduate degree in Physics, Band continued as a graduate student in Physics at Harvard University. His emerging interest in Astrophysics led him to the Astronomy Department at the Harvard Smithsonian Center for Astrophysics (CfA), where he did his dissertation work with Jonathan Grindlay. His dissertation (1985) entitled "Non-thermal Radiation Mechanisms and Processes in SS433 and Active Galactic Nuclei" was "pioneering work on the physics of jets arising from black holes and models for their emission, including self-absorption, which previewed much to come, and even David's own later work on Gamma-ray Bursts," according to Grindlay who remained a personal friend and colleague of Band's. Following graduate school, Band held postdoctoral positions at the Lawrence Livermore Laboratory, the University of California at Berkeley and the Center for Astronomy and Space Sciences at the University of California San Diego where he worked on the BATSE experiment that was part of the Compton Gamma Ray Observatory (CGRO), launched in 1991. BATSE had as its main objective the study of cosmic gamma-ray bursts (GRBs) and made significant advances in this area of research. Band became a world-renowned figure in the emerging field of GRB studies. He is best known for his widely-used analytic form of gamma-ray burst spectra known as the "Band Function." After the CGRO mission ended, Band moved to the Los Alamos National Laboratory where he worked mainly on classified research but continued to work on GRB energetics and spectra. When NASA planned

  5. Simplicial band depth for multivariate functional data

    KAUST Repository

    López-Pintado, Sara

    2014-03-05

    We propose notions of simplicial band depth for multivariate functional data that extend the univariate functional band depth. The proposed simplicial band depths provide simple and natural criteria to measure the centrality of a trajectory within a sample of curves. Based on these depths, a sample of multivariate curves can be ordered from the center outward and order statistics can be defined. Properties of the proposed depths, such as invariance and consistency, can be established. A simulation study shows the robustness of this new definition of depth and the advantages of using a multivariate depth versus the marginal depths for detecting outliers. Real data examples from growth curves and signature data are used to illustrate the performance and usefulness of the proposed depths. © 2014 Springer-Verlag Berlin Heidelberg.

  6. Effect of morbid obesity, gastric banding and gastric bypass on esophageal symptoms, mucosa and function.

    Science.gov (United States)

    Borovicka, Jan; Krieger-Grübel, Claudia; van der Weg, Boudewijn; Thurnheer, Martin; Schultes, Bernd; Sulz, Michael Christian; Gutzwiler, Jean-Pierre; Bisang, Philipp; Pohl, Daniel; Fried, Michael; Meyenberger, Christa; Tutuian, Radu

    2017-02-01

    Obesity and gastroesophageal reflux disease (GERD) are commonly associated diseases. Bariatric surgery has been shown to have various impacts on esophageal function and GERD. Our aim was to evaluate changes in symptoms, endoscopic findings, bolus passage and esophageal function in patients after primary gastric bypass surgery as compared to patients converted from gastric banding to gastric bypass. Obese patients scheduled for laparoscopic Roux-en-Y gastric bypass (naïve-to-bypass) and patients who previously underwent gastric banding and were considered for conversion from gastric banding to gastric bypass (band-to-bypass) were included. Patients rated esophageal and epigastric symptoms (100 point VAS) and underwent upper endoscopy, impedance-manometry, and modified "timed barium swallow" before/after surgery. Data from 66 naïve-to-bypass patients (51/66, 77 % females, mean age 41.2 ± 11.1 years) and 68 band-to-bypass patients (53/68, 78 % females, mean age 43.8 ± 10.0 years) were available for analysis. Esophageal symptoms, esophagitis, esophageal motility abnormalities and impaired esophageal bolus transit were more common in patients that underwent gastric banding compared to those that underwent gastric bypass. The majority of symptoms, lesions and abnormalities induced by gastric banding were decreased by conversion to gastric bypass. Esophagitis was present in 28/68 (41 %) and 13/47 (28 %) patients in the band-to-bypass group, pre- versus postoperatively, respectively, (p symptoms and should be therefore favored over gastric banding in difficult to treat obese patients at risk of repeated bariatric surgery.

  7. Determination of Primary Spectral Bands for Remote Sensing of Aquatic Environments

    Directory of Open Access Journals (Sweden)

    MingXia He

    2007-12-01

    Full Text Available About 30 years ago, NASA launched the first ocean-color observing satellite:the Coastal Zone Color Scanner. CZCS had 5 bands in the visible-infrared domain with anobjective to detect changes of phytoplankton (measured by concentration of chlorophyll inthe oceans. Twenty years later, for the same objective but with advanced technology, theSea-viewing Wide Field-of-view Sensor (SeaWiFS, 7 bands, the Moderate-ResolutionImaging Spectrometer (MODIS, 8 bands, and the Medium Resolution ImagingSpectrometer (MERIS, 12 bands were launched. The selection of the number of bands andtheir positions was based on experimental and theoretical results achieved before thedesign of these satellite sensors. Recently, Lee and Carder (2002 demonstrated that foradequate derivation of major properties (phytoplankton biomass, colored dissolved organicmatter, suspended sediments, and bottom properties in both oceanic and coastalenvironments from observation of water color, it is better for a sensor to have ~15 bands inthe 400 – 800 nm range. In that study, however, it did not provide detailed analysesregarding the spectral locations of the 15 bands. Here, from nearly 400 hyperspectral (~ 3-nm resolution measurements of remote-sensing reflectance (a measure of water colortaken in both coastal and oceanic waters covering both optically deep and optically shallowwaters, first- and second-order derivatives were calculated after interpolating themeasurements to 1-nm resolution. From these derivatives, the frequency of zero values foreach wavelength was accounted for, and the distribution spectrum of such frequencies wasobtained. Furthermore, the wavelengths that have the highest appearance of zeros wereidentified. Because these spectral locations indicate extrema (a local maximum orminimum of the reflectance spectrum or inflections of the spectral curvature, placing the bands of a sensor at these wavelengths maximizes the potential of capturing (and then restoring

  8. Band Edge Dynamics and Multiexciton Generation in Narrow Band Gap HgTe Nanocrystals.

    Science.gov (United States)

    Livache, Clément; Goubet, Nicolas; Martinez, Bertille; Jagtap, Amardeep; Qu, Junling; Ithurria, Sandrine; Silly, Mathieu G; Dubertret, Benoit; Lhuillier, Emmanuel

    2018-04-02

    Mercury chalcogenide nanocrystals and especially HgTe appear as an interesting platform for the design of low cost mid-infrared (mid-IR) detectors. Nevertheless, their electronic structure and transport properties remain poorly understood, and some critical aspects such as the carrier relaxation dynamics at the band edge have been pushed under the rug. Some of the previous reports on dynamics are setup-limited, and all of them have been obtained using photon energy far above the band edge. These observations raise two main questions: (i) what are the carrier dynamics at the band edge and (ii) should we expect some additional effect (multiexciton generation (MEG)) as such narrow band gap materials are excited far above the band edge? To answer these questions, we developed a high-bandwidth setup that allows us to understand and compare the carrier dynamics resonantly pumped at the band edge in the mid-IR and far above the band edge. We demonstrate that fast (>50 MHz) photoresponse can be obtained even in the mid-IR and that MEG is occurring in HgTe nanocrystal arrays with a threshold around 3 times the band edge energy. Furthermore, the photoresponse can be effectively tuned in magnitude and sign using a phototransistor configuration.

  9. S-band active array filtenna with enhanced X-band spurious interference suppression

    NARCIS (Netherlands)

    Cifola, L.; Gerini, G.; Berg, S. van den; Water, F. van de

    2014-01-01

    In the present work, the design of an S-band active array antenna with inherent frequency selectivity properties is described. The radiating element, based on a stacked-patch configuration, is characterized by an operational bandwidth of [2.8-3.4] GHz. In-band frequency selectivity is performed by a

  10. Fuzzy Riesz subspaces, fuzzy ideals, fuzzy bands and fuzzy band projections

    OpenAIRE

    Hong, Liang

    2015-01-01

    Fuzzy ordered linear spaces, Riesz spaces, fuzzy Archimedean spaces and $\\sigma$-complete fuzzy Riesz spaces were defined and studied in several works. Following the efforts along this line, we define fuzzy Riesz subspaces, fuzzy ideals, fuzzy bands and fuzzy band projections and establish their fundamental properties.

  11. Band-gap and band-edge engineering of multicomponent garnet scintillators from first principles

    Czech Academy of Sciences Publication Activity Database

    Yadav, S.K.; Uberuaga, B.P.; Nikl, Martin; Jiang, C.; Stanek, C.R.

    2015-01-01

    Roč. 4, č. 5 (2015), "054012-1"-"054012-9" ISSN 2331-7019 R&D Projects: GA ČR GAP204/12/0805 Institutional support: RVO:68378271 Keywords : scintillator * electronic band gap structure * garnets * band gap engineering Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 4.061, year: 2015

  12. Electron currents associated with an auroral band

    Science.gov (United States)

    Spiger, R. J.; Anderson, H. R.

    1975-01-01

    Measurements of electron pitch angle distributions and energy spectra over a broad auroral band were used to calculate net electric current carried by auroral electrons in the vicinity of the band. The particle energy spectrometers were carried by a Nike-Tomahawk rocket launched from Poker Flat, Alaska, at 0722 UT on February 25, 1972. Data are presented which indicate the existence of upward field-aligned currents of electrons in the energy range 0.5-20 keV. The spatial relationship of these currents to visual structure of the auroral arc and the characteristics of the electrons carrying the currents are discussed.

  13. Itinerant ferromagnetism in the narrow band limit

    CERN Document Server

    Liu, S H

    2000-01-01

    It is shown that in the narrow band, strong interaction limit the paramagnetic state of an itinerant ferromagnet is described by the disordered local moment state. As a result, the Curie temperature is orders of magnitude lower than what is expected from the large exchange splitting of the spin bands. An approximate analysis has also been carried out for the partially ordered state, and the result explains the temperature evolvement of the magnetic contributions to the resistivity and low-energy optical conductivity of CrO sub 2.

  14. Banding of connection standards for distributed generation

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-05-04

    This report presents the views of distributed network operators (DNOs), developers, equipment manufacturers and consultants on the current banding of distributed generation in terms of connection standards and recommendations. The Documents ER G59/1, ER G75/1, ER G83/1 and ETR 113/1 covering recommendations for the connection of embedded generating plant to distribution systems and guidance notes for the protection of embedded generating plant are examined. The way in which the recommendations are applied in practice is investigated. Multiple distribution generator installations, fault ride through, and banding are considered as well as both protection required and maximum generator sizes at respective voltage levels.

  15. Band theory of metals the elements

    CERN Document Server

    Altmann, Simon L

    1970-01-01

    Band Theory of Metals: The Elements focuses on the band theory of solids. The book first discusses revision of quantum mechanics. Topics include Heisenberg's uncertainty principle, normalization, stationary states, wave and group velocities, mean values, and variational method. The text takes a look at the free-electron theory of metals, including heat capacities, density of states, Fermi energy, core and metal electrons, and eigenfunctions in three dimensions. The book also reviews the effects of crystal fields in one dimension. The eigenfunctions of the translations; symmetry operations of t

  16. Proximal iliotibial band syndrome: case report

    Directory of Open Access Journals (Sweden)

    Guilherme Guadagnini Falotico

    2013-08-01

    Full Text Available OBJECTIVE: The overuse injuries in the hip joint occur commonly in sports practitioners and currently due to technical advances in diagnostic imaging, especially magnetic resonance imaging (MRI, are often misdiagnosed. Recently, a group of people were reported, all female, with pain and swelling in the pelvic region.T2-weighted MRI showed increased signal in the enthesis of the iliotibial band (ITB along the lower border of the iliac tubercle. We report a case of a 34 year old woman, non-professional runner, with pain at the iliac crest with no history of trauma and whose MRI was compatible with the proximal iliotibial band syndrome.

  17. Ka-band waveguide rotary joint

    KAUST Repository

    Yevdokymov, Anatoliy

    2013-04-11

    The authors present a design of a waveguide rotary joint operating in Ka-band with central frequency of 33 GHz, which also acts as an antenna mount. The main unit consists of two flanges with a clearance between them; one of the flanges has three circular choke grooves. Utilisation of three choke grooves allows larger operating clearance. Two prototypes of the rotary joint have been manufactured and experimentally studied. The observed loss is from 0.4 to 0.8 dB in 1.5 GHz band.

  18. Radiology of vertical-banded gastroplasty

    International Nuclear Information System (INIS)

    Leekam, R.N.; Deitel, M.; Shankar, L.; Salsberg, B.B.

    1987-01-01

    Vertical banded gastroplasty is the most frequently performed operation for the treatment of morbid obesity. More than 550 such procedures have been done at our hospital over the past 4 years. This presentation describes the postoperative radiographic findings in many of these patients. Normal and abnormal appearances on plain films and on contrast agent-enhanced examinations are discussed. The authors found it useful to divide abnormal findings into three groups: abnormalities of the partition, abnormalities of the banded channel, and ulcers and extragastric leaks

  19. Airborne Multi-Band SAR in the Arctic

    Science.gov (United States)

    Gardner, J. M.; Brozena, J. M.; Liang, R.; Ball, D.; Holt, B.; Thomson, J.

    2016-12-01

    As one component of the Office of Naval Research supported Sea State Departmental Research Initiative during October of 2015 the Naval Research Laboratory flew an ultrawide-band, low-frequency, polarimetric SAR over the southward advancing sea ice in Beaufort Sea. The flights were coordinated with the research team aboard the R/V Sikuliaq working near and in the advancing pack ice. The majority of the SAR data were collected with the L-Band sensor (1000-1500 MHz) from an altitude of 10,000', providing a useful swath 6 km wide with 75o and 25 o angles of incidence at the inner and outer edge of the swath respectively. Some data were also collected with the P-Band SAR (215-915 MHz). The extremely large bandwidths allowed for formation of image pixels as small as 30 cm, however, we selected 60 cm pixel size to reduce image speckle. The separate polarimetric images are calibrated to one pixel to allow for calculations such as polarimetric decompositions that require the images to be well aligned. Both frequencies are useful particularly for the detection of ridges and areas of deformed ice. There are advantages and disadvantages to airborne SAR imagery compared to satellites. The chief advantages being the enormous allowable bandwidth leading to very fine range resolution, and the ability to fly arbitrary trajectories on demand. The latter permits specific areas to be imaged at a given time with a specified illumination direction. An area can even be illuminated from all directions by flying a circular trajectory around the target area. This captures ice features that are sensitive to illumination direction such as cracks, sastrugi orientation, and ridges. The disadvantages include variation of intensity across the swath with range and incidence angle. In addition to the SAR data, we collected photogrammetric imagery from a DSS-439, scanning lidar from a Riegl Q560 and surface brightness temperatures from a KT-19. However, since all of these sensors are nadir pointing

  20. Wavelet-RX anomaly detection for dual-band forward-looking infrared imagery.

    Science.gov (United States)

    Mehmood, Asif; Nasrabadi, Nasser M

    2010-08-20

    This paper describes a new wavelet-based anomaly detection technique for a dual-band forward-looking infrared (FLIR) sensor consisting of a coregistered longwave (LW) with a midwave (MW) sensor. The proposed approach, called the wavelet-RX (Reed-Xiaoli) algorithm, consists of a combination of a two-dimensional (2D) wavelet transform and a well-known multivariate anomaly detector called the RX algorithm. In our wavelet-RX algorithm, a 2D wavelet transform is first applied to decompose the input image into uniform subbands. A subband-image cube is formed by concatenating together a number of significant subbands (high-energy subbands). The RX algorithm is then applied to the subband-image cube obtained from a wavelet decomposition of the LW or MW sensor data. In the case of the dual band, the RX algorithm is applied to a subband-image cube constructed by concatenating together the high-energy subbands of the LW and MW subband-image cubes. Experimental results are presented for the proposed wavelet-RX and the classical constant false alarm rate (CFAR) algorithm for detecting anomalies (targets) in a single broadband FLIR (LW or MW) or in a coregistered dual-band FLIR sensor. The results show that the proposed wavelet-RX algorithm outperforms the classical CFAR detector for both single-band and dual-band FLIR sensors.

  1. Bipolar disorder: Evidence for a major locus

    Energy Technology Data Exchange (ETDEWEB)

    Spence, M.A.; Flodman, P.L. [Univ. of California, Irvine, CA (United States); Sadovnick, A.D.; Ameli, H. [Univ. of British Columbia, Vancouver (Canada)] [and others

    1995-10-09

    Complex segregation analyses were conducted on families of bipolar I and bipolar II probands to delineate the mode of inheritance. The probands were ascertained from consecutive referrals to the Mood Disorder Service, University Hospital, University of British Columbia and diagnosed by DSM-III-R and Research Diagnostic Criteria. Data were available on over 1,500 first-degree relatives of the 186 Caucasian probands. The purpose of the analyses was to determine if, after correcting for age and birth cohort, there was evidence for a single major locus. Five models were fit to the data using the statistical package SAGE: (1) dominant, (2) recessive, (3) arbitrary mendelian inheritance, (4) environmental, and (5) no major effects. A single dominant, mendelian major locus was the best fitting of these models for the sample of bipolar I and II probands when only bipolar relatives were defined as affected (polygenic inheritance could not be tested). Adding recurrent major depression to the diagnosis {open_quotes}affected{close_quotes} for relatives reduced the evidence for a major locus effect. Our findings support the undertaking of linkage studies and are consistent with the analyses of the National Institutes of Mental Health (NIMH) Collaborative Study data by Rice et al. and Blangero and Elston. 39 refs., 4 tabs.

  2. ANALISIS TIPOGRAFI PADA LOGOTYPE BAND FORGOTTEN

    Directory of Open Access Journals (Sweden)

    Atang Riyan Isnandar

    2016-12-01

    Full Text Available Abstrak Forgotten merupakan band asal kota Bandung yang beraliran death metal. Band ini telah memiliki beberapa album yang cukup sukses. Salah satu faktor yang turut berperan penting dalam album-album Forgotten adalah desain sampul album. Sampul album merupakan identitas dan pesan dari musik yang dibawakan oleh Forgotten. Dalam sampul album, terdapat salah satu elemen visual yaitu Tipografi. Salah satu peran tipografi dalam sampul album Forgotten adalah sebagai logotype dari band. Yang menarik, dari lima album yang telah dirilis Forgotten yaitu “Future Syndrome” (1997, “Obsesi Mati” (2000, “Tuhan Telah Mati” (2001, “Tiga Angka Enam” (2003 dan “Laras Perlaya” (2011 adalah tampilan logotype band yang selalu berbeda. Perubahan logotype Forgotten disebabkan oleh beberapa faktor seperti adanya perubahan selera, transformasi musik dan pergantian personil yang dialami oleh band Forgotten. Perubahan ini berakibat pada munculnya kesan visual yang berbeda-beda dari masing-masing logotype di setiap sampul albumnya. Apalagi logotype band dengan genre death metal memiliki kecendrungan yang unik, dekoratif, bahkan sulit untuk dibaca. Oleh karena itu untuk mengetahui kesan visual yang dimunculkan oleh setiap logotype akan dilakukan penelitian dengan pendekatan tipografi. Tujuan dari penelitian ini adalah selain untuk mengetahui perubahan logotype dari kelima sampul album yang telah dirilis oleh Forgotten juga ingin mengetahui kesan visual terhadap tipografi terkait dengan prinsip kejelasan (legibility, keterbacaan (readability dan kemampuannya untuk dilihat pada jarak tertentu (visibility. Kata Kunci: Sampul Album, Tipografi, Logotype, Forgotten Abstract Forgotten is a band from Bandung, the death metal genre. The band has had some fairly successful album. One of important factor in albums Forgotten is the album cover design. The album cover are the identity and the message of the music performed by the Forgotten. In the cover of the album

  3. Selective Area Band Engineering of Graphene using Cobalt-Mediated Oxidation.

    Science.gov (United States)

    Bazylewski, Paul F; Nguyen, Van Luan; Bauer, Robert P C; Hunt, Adrian H; McDermott, Eamon J G; Leedahl, Brett D; Kukharenko, Andrey I; Cholakh, Seif O; Kurmaev, Ernst Z; Blaha, Peter; Moewes, Alexander; Lee, Young Hee; Chang, Gap Soo

    2015-10-21

    This study reports a scalable and economical method to open a band gap in single layer graphene by deposition of cobalt metal on its surface using physical vapor deposition in high vacuum. At low cobalt thickness, clusters form at impurity sites on the graphene without etching or damaging the graphene. When exposed to oxygen at room temperature, oxygen functional groups form in proportion to the cobalt thickness that modify the graphene band structure. Cobalt/Graphene resulting from this treatment can support a band gap of 0.30 eV, while remaining largely undamaged to preserve its structural and electrical properties. A mechanism of cobalt-mediated band opening is proposed as a two-step process starting with charge transfer from metal to graphene, followed by formation of oxides where cobalt has been deposited. Contributions from the formation of both CoO and oxygen functional groups on graphene affect the electronic structure to open a band gap. This study demonstrates that cobalt-mediated oxidation is a viable method to introduce a band gap into graphene at room temperature that could be applicable in electronics applications.

  4. Selective Area Band Engineering of Graphene using Cobalt-Mediated Oxidation

    Science.gov (United States)

    Bazylewski, Paul F.; Nguyen, Van Luan; Bauer, Robert P.C.; Hunt, Adrian H.; McDermott, Eamon J. G.; Leedahl, Brett D.; Kukharenko, Andrey I.; Cholakh, Seif O.; Kurmaev, Ernst Z.; Blaha, Peter; Moewes, Alexander; Lee, Young Hee; Chang, Gap Soo

    2015-01-01

    This study reports a scalable and economical method to open a band gap in single layer graphene by deposition of cobalt metal on its surface using physical vapor deposition in high vacuum. At low cobalt thickness, clusters form at impurity sites on the graphene without etching or damaging the graphene. When exposed to oxygen at room temperature, oxygen functional groups form in proportion to the cobalt thickness that modify the graphene band structure. Cobalt/Graphene resulting from this treatment can support a band gap of 0.30 eV, while remaining largely undamaged to preserve its structural and electrical properties. A mechanism of cobalt-mediated band opening is proposed as a two-step process starting with charge transfer from metal to graphene, followed by formation of oxides where cobalt has been deposited. Contributions from the formation of both CoO and oxygen functional groups on graphene affect the electronic structure to open a band gap. This study demonstrates that cobalt-mediated oxidation is a viable method to introduce a band gap into graphene at room temperature that could be applicable in electronics applications. PMID:26486966

  5. Band-Gap Engineering at a Semiconductor-Crystalline Oxide Interface

    Energy Technology Data Exchange (ETDEWEB)

    Moghadam, Mohammadreza J. [Univ. of Texas, Arlington, TX (United States); Ahmadi-Majlan, K. [Univ. of Texas, Arlington, TX (United States); Shen, Xuan [Brookhaven National Lab. (BNL), Upton, NY (United States); Nanjing Univ. (China); Droubay, Timothy C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bowden, Mark E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Chrysler, M. [Univ. of Texas, Arlington, TX (United States); Su, Dong [Brookhaven National Lab. (BNL), Upton, NY (United States); Chambers, Scott A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Ngai, Joseph [Univ. of Texas, Arlington, TX (United States)

    2015-02-09

    The epitaxial growth of crystalline oxides on semiconductors provides a pathway to introduce new functionalities to semiconductor devices. Key to electrically coupling crystalline oxides with semiconductors to realize functional behavior is controlling the manner in which their bands align at interfaces. Here we apply principles of band gap engineering traditionally used at heterojunctions between conventional semiconductors to control the band offset between a single crystalline oxide and a semiconductor. Reactive molecular beam epitaxy is used to realize atomically abrupt and structurally coherent interfaces between SrZrxTi1-xO3 and Ge, in which the band gap of the former is enhanced with Zr content x. We present structural, electrical and photoemission characterization of SrZrxTi1-xO33-Ge heterojunctions for x = 0.2 to 0.75 and demonstrate the band offset can be tuned from type-II to type-I. The type-I band offset provides a platform to integrate the dielectric, ferroelectric and ferromagnetic functionalities of oxides with semiconducting devices.

  6. Correlation of S-Band Weather Radar Reflectivity and ACTS Propagation Data in Florida

    Science.gov (United States)

    Wolfe, Eric E.; Flikkema, Paul G.; Henning, Rudolf E.

    1997-01-01

    Previous work has shown that Ka-band attenuation due to rainfall and corresponding S-band reflectivity are highly correlated. This paper reports on work whose goal is to determine the feasibility of estimation and, by extension, prediction of one parameter from the other using the Florida ACTS propagation terminal (APT) and the nearby WSR-88D S-band Doppler weather radar facility operated by the National Weather Service. This work is distinguished from previous efforts in this area by (1) the use of a single-polarized radar, preventing estimation of the drop size distribution (e.g., with dual polarization) and (2) the fact that the radar and APT sites are not co-located. Our approach consists of locating the radar volume elements along the satellite slant path and then, from measured reflectivity, estimating the specific attenuation for each associated path segment. The sum of these contributions yields an estimation of the millimeter-wave attenuation on the space-ground link. Seven days of data from both systems are analyzed using this procedure. The results indicate that definite correlation of S-band reflectivity and Ka-band attenuation exists even under the restriciton of this experiment. Based on these results, it appears possible to estimate Ka-band attenuation using widely available operational weather radar data. Conversely, it may be possible to augment current radar reflectivity data and coverage with low-cost attenuation or sky temperature data to improve the estimation of rain rates.

  7. Flat band in disorder-driven non-Hermitian Weyl semimetals

    Science.gov (United States)

    Zyuzin, A. A.; Zyuzin, A. Yu.

    2018-01-01

    We study the interplay of disorder and band-structure topology in a Weyl semimetal with a tilted conical spectrum around the Weyl points. The spectrum of particles is given by the eigenvalues of a non-Hermitian matrix, which contains contributions from a Weyl Hamiltonian and complex self-energy due to electron elastic scattering on disorder. We find that the tilt-induced matrix structure of the self-energy gives rise to either a flat band or a nodal line segment at the interface of the electron and hole pockets in the bulk band structure of type-II Weyl semimetals depending on the Weyl cone inclination. For the tilt in a single direction in momentum space, each Weyl point expands into a flat band lying on the plane, which is transverse to the direction of the tilt. The spectrum of the flat band is fully imaginary and is separated from the in-plane dispersive part of the spectrum by the "exceptional nodal ring" where the matrix of the Green's function in momentum-frequency space is defective. The tilt in two directions might shrink a flat band into a nodal line segment with "exceptional edge points." We discuss the connection to the non-Hermitian topological theory.

  8. Effect of band gap engineering in anionic-doped TiO2 photocatalyst

    Science.gov (United States)

    Samsudin, Emy Marlina; Abd Hamid, Sharifah Bee

    2017-01-01

    A simple yet promising strategy to modify TiO2 band gap was achieved via dopants incorporation which influences the photo-responsiveness of the photocatalyst. The mesoporous TiO2 was successfully mono-doped and co-doped with nitrogen and fluorine dopants. The results indicate that band gap engineering does not necessarily requires oxygen substitution with nitrogen or/and fluorine, but from the formation of additional mid band and Ti3+ impurities states. The formation of oxygen vacancies as a result of modified color centres and Ti3+ ions facilitates solar light absorption and influences the transfer, migration and trapping of the photo-excited charge carriers. The synergy of dopants in co-doped TiO2 shows better optical properties relative to single N and F doped TiO2 with c.a 0.95 eV band gap reduction. Evidenced from XPS, the synergy between N and F in the co-doped TiO2 uplifts the valence band towards the conduction band. However, the photoluminescence data reveals poorer electrons and holes separation as compared to F-doped TiO2. This observation suggests that efficient solar light harvesting was achievable via N and F co-doping, but excessive defects could act as charge carriers trapping sites.

  9. Superelastic NiTi memory alloy micro-tube under tension - nucleation and propagation of martensite band

    International Nuclear Information System (INIS)

    Li, Z.Q.; Sun, Q.P.

    2000-01-01

    The superelastic behavior of polycrystalline NiTi shape memory alloy micro-tube under tension is studied experimentally. The nominal stress-strain curve of the micro-tube is recorded. By using a special surface coating it is found that the deformation of the tube is via the nucleation and propagation of stress-induced martensite band. The experiments show that the martensite nucleates in the form of a spiral lens-shaped narrow band that is inclined at 61 to the axis of loading when the stress reaches the peak of stress-strain curve. The width and the length of the band grew gradually with increase of loading and finally joined and merged into a single band. The subsequent deformation of the tube is realized by the propagation of this cylindrical martensite band. (orig.)

  10. Electron microscopic and physicobiochemical studies on disorganization of the cytoskeletal network and integral protein (band 3) in red cells of band 4.2 deficiency with a mutation (codon 142: GCT-->ACT).

    Science.gov (United States)

    Inoue, T; Kanzaki, A; Yawata, A; Tsuji, A; Ata, K; Okamoto, N; Wada, H; Higo, I; Sugihara, T; Yamada, O

    1994-04-01

    The role of band 4.2 deficiency in the pathogenesis of red cell membrane dysfunctions was studied in seven unrelated patients with complete band 4.2 deficiency with a point mutation (142 GCT-->ACT; 142 Ala-->Thr) on the cDNA of the band 4.2 gene. Two major types of abnormalities were detected in these patients; (A) abnormalities of the cytoskeletal network in the horizontal dimension, and (B) abnormalities of band 3 in the vertical dimension. Electron microscopy by the surface replica method and the quick-freeze deep-etching method demonstrated the markedly impaired cytoskeletal network (a disorganized cobblestone pattern, uneven distribution of junctional units, and the appearance of bulky aggregates after heat treatment). Ektacytometry showed a markedly decreased red cell deformability especially at 48 degrees C, although the cytoskeletal proteins themselves were essentially normal with normal mechanical stability of the Triton-shells. Electron microscopy by the freeze fracture method revealed a decreased number and a random distribution of intramembrane particles (IMPs) with a shift of the IMPs to a larger size. Fluorescence recovery after photobleaching studies on band 3 indicated the marked increase of its mobile fraction. The extractability of band 3 by Triton X in vitro was markedly enhanced, although the physico-biochemical properties of band 3 itself (the cleavage pattern of band 3 fragments, and the binding properties of band 3 to band 4.2 or ankyrin) were basically normal. These findings demonstrate that band 4.2 plays a crucial role in the maintenance of the normal structure and functions of both the cytoskeletal and integral proteins (band 3).

  11. 47 CFR 15.714 - TV bands database administration fees.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false TV bands database administration fees. 15.714 Section 15.714 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Television Band Devices § 15.714 TV bands database administration fees. (a) A TV bands database administrator...

  12. 47 CFR 15.715 - TV bands database administrator.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false TV bands database administrator. 15.715 Section... Band Devices § 15.715 TV bands database administrator. The Commission will designate one or more entities to administer a TV bands database. Each database administrator shall: (a) Maintain a database that...

  13. New Kronig-Penney Equation Emphasizing the Band Edge Conditions

    Science.gov (United States)

    Szmulowicz, Frank

    2008-01-01

    The Kronig-Penney problem is a textbook example for discussing band dispersions and band gap formation in periodic layered media. For example, in photonic crystals, the behaviour of bands next to the band edges is important for further discussions of such effects as inhibited light emission, slow light and negative index of refraction. However,…

  14. Predicting superdeformed rotational band-head spin in A∼ 190 ...

    Indian Academy of Sciences (India)

    The band-head spin (0) of superdeformed (SD) rotational bands in ∼ 190 mass region is predicted using the variable moment of inertia (VMI) model for 66 SD rotational bands. The superdeformed rotational bands exhibited considerably good rotational property and rigid behaviour. The transition energies were ...

  15. Quantitative analysis of X-band weather radar attenuation correction accuracy

    NARCIS (Netherlands)

    Berne, A.D.; Uijlenhoet, R.

    2006-01-01

    At short wavelengths, especially C-, X-, and K-band, weather radar signals arc attenuated by the precipitation along their paths. This constitutes a major source of error for radar rainfall estimation, in particular for intense precipitation. A recently developed stochastic simulator of range

  16. The Relationship between Collegiate Band Members' Preferences of Teacher Interpersonal Behavior and Perceived Self-Efficacy

    Science.gov (United States)

    Royston, Natalie Steele

    2013-01-01

    The purposes of this study were to describe collegiate band members' preferred teacher interpersonal behaviors and perceptions of self-efficacy based on the gender, year in college, instrument, and major and to measure the relationship between preferences of interpersonal teacher behavior and self-efficacy scores. The sample (N = 1,020) was…

  17. Statistical study of auroral omega bands

    Directory of Open Access Journals (Sweden)

    N. Partamies

    2017-09-01

    Full Text Available The presence of very few statistical studies on auroral omega bands motivated us to test-use a semi-automatic method for identifying large-scale undulations of the diffuse aurora boundary and to investigate their occurrence. Five identical all-sky cameras with overlapping fields of view provided data for 438 auroral omega-like structures over Fennoscandian Lapland from 1996 to 2007. The results from this set of omega band events agree remarkably well with previous observations of omega band occurrence in magnetic local time (MLT, lifetime, location between the region 1 and 2 field-aligned currents, as well as current density estimates. The average peak emission height of omega forms corresponds to the estimated precipitation energies of a few keV, which experienced no significant change during the events. Analysis of both local and global magnetic indices demonstrates that omega bands are observed during substorm expansion and recovery phases that are more intense than average substorm expansion and recovery phases in the same region. The omega occurrence with respect to the substorm expansion and recovery phases is in a very good agreement with an earlier observed distribution of fast earthward flows in the plasma sheet during expansion and recovery phases. These findings support the theory that omegas are produced by fast earthward flows and auroral streamers, despite the rarity of good conjugate observations.

  18. S-Band Doppler Wave Radar System

    Directory of Open Access Journals (Sweden)

    Zezong Chen

    2017-12-01

    Full Text Available In this paper, a novel shore-based S-band microwave Doppler coherent wave radar (Microwave Ocean Remote SEnsor (MORSE is designed to improve wave measurements. Marine radars, which operate in the X band, have been widely used for ocean monitoring because of their low cost, small size and flexibility. However, because of the non-coherent measurements and strong absorption of X-band radio waves by rain, these radar systems suffer considerable performance loss in moist weather. Furthermore, frequent calibrations to modify the modulation transfer function are required. To overcome these shortcomings, MORSE, which operates in the S band, was developed by Wuhan University. Because of the coherent measurements of this sensor, it is able to measure the radial velocity of water particles via the Doppler effect. Then the relation between the velocity spectrum and wave height spectrum can be used to obtain the wave height spectra. Finally, wave parameters are estimated from the wave height spectra by the spectrum moment method. Comparisons between MORSE and Waverider MKIII are conducted in this study, and the results, including the non-directional wave height spectra, significant wave height and average wave period, are calculated and displayed. The correlation coefficient of the significant wave height is larger than 0.9, whereas that of the average wave period is approximately 0.4, demonstrating the effectiveness of MORSE for the continuous monitoring of ocean areas with high accuracy.

  19. Deformed configurations, band structures and spectroscopic ...

    Indian Academy of Sciences (India)

    2014-03-20

    Mar 20, 2014 ... The deformed configurations and rotational band structures in =50 Ge and Se nuclei are studied by deformed Hartree–Fock with quadrupole constraint and angular momentum projection. Apart from the `almost' spherical HF solution, a well-deformed configuration occurs at low excitation. A deformed ...

  20. Deformed configurations, band structures and spectroscopic ...

    Indian Academy of Sciences (India)

    2014-03-20

    Mar 20, 2014 ... Here, we study theoretically the low-lying as well as the excited deformed bands and their electromagnetic properties to search for various structures, spherical and deformed, of the exotic nuclei 82Ge and 84Se by employing the deformed Hartree–Fock (HF) and angular momentum (J) projection method ...

  1. Energy bands and gaps near an impurity

    Czech Academy of Sciences Publication Activity Database

    Mihóková, Eva; Schulman, L. S.

    2016-01-01

    Roč. 380, č. 41 (2016), s. 3430-3433 ISSN 0375-9601 R&D Projects: GA ČR GA13-09876S Institutional support: RVO:68378271 Keywords : crystal structure * impurity * modeling * energy bands Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.772, year: 2016

  2. Teaching Strategies for High School Band.

    Science.gov (United States)

    Teaching Music, 1999

    1999-01-01

    Provides a strategy, from the book entitled "Strategies for Teaching High School Band," that addresses Standard 8B of the National Standards for Music Education. Explains that students will discover relationships among music, visual art, and architecture of the Classical period. (CMK)

  3. The end of the unique myocardial band

    DEFF Research Database (Denmark)

    MacIver, David H; Partridge, John B; Agger, Peter

    2018-01-01

    Two of the leading concepts of mural ventricular architecture are the unique myocardial band and the myocardial mesh model. We have described, in an accompanying article published in this journal, how the anatomical, histological and high-resolution computed tomographic studies strongly favour...

  4. Faraday Rotation and L Band Oceanographic Measurements

    DEFF Research Database (Denmark)

    Skou, Niels

    2003-01-01

    Spaceborne radiometric measurements of the L band brightness temperature over the oceans make it possible to estimate sea surface salinity. However, Faraday rotation in the ionosphere disturbs the signals and must be corrected. Two different ways of assessing the disturbance directly from...

  5. Phononic band gap structures as optimal designs

    DEFF Research Database (Denmark)

    Jensen, Jakob Søndergaard; Sigmund, Ole

    2003-01-01

    In this paper we use topology optimization to design phononic band gap structures. We consider 2D structures subjected to periodic loading and obtain the distribution of two materials with high contrast in material properties that gives the minimal vibrational response of the structure. Both in...

  6. Conduction bands in classical periodic potentials

    Indian Academy of Sciences (India)

    The particle may hop from classically allowed site to nearest-neighbour classically allowed site in the potential, behaving as if it were a quantum particle in an energy gap and undergoing repeated tunnelling processes or; the particle may behave as a quantum particle in a conduction band and drift at a constant average ...

  7. PHARUS: A C-band Airborne SAR

    NARCIS (Netherlands)

    Hoogeboom, P.; Koomen, P.J.; Pouwels, H.; Snoeij, P.

    1990-01-01

    In The Netherlands a plan to design aircraft and build a polarimetric C-band SAR system of a novel design, called PHARUS (PHased Array Universal SAR) is carried out by three institutes. These institutes are the Physics and Electronics Laboratory TNO in The Hague (prime contractor and project

  8. Superdeformed rotational bands in Pu-240

    NARCIS (Netherlands)

    Hunyadi, M; Gassmann, D; Krasznahorkay, A; Habs, D; Csatlos, M; Eisermann, Y; Faestermann, T; Graw, G; Gulyas, J; Hertenberger, R; Maier, HJ; Mate, Z; Metz, A; Thirolf, P; Chromik, M; van der Werf, SY

    The intermediate structure of the fission resonances has been observed in Pu-240. A resonance structure found around the excitation energy of 4.5 MeV was interpreted as a group of K-pi = 0(+) superdeformed rotational bands. The moments of inertia and level density distributions were also deduced for

  9. Band-Structure of Thallium by the LMTO Method

    DEFF Research Database (Denmark)

    Holtham, P. M.; Jan, J. P.; Skriver, Hans Lomholt

    1977-01-01

    The relativistic band structure of thallium has been calculated using the linear muffin-tin orbital (LMTO) method. The positions and extents of the bands were found to follow the Wigner-Seitz rule approximately, and the origin of the dispersion of the bands was established from the canonical s...... and p bands for the HCP structure. Energy bands have been evaluated both with and without spin-orbit coupling which is particularly large in thallium. Energy bands close to the Fermi level were found to be mainly 6p like in character. The 6s states lay below the 6p bands and were separated from them...

  10. Frequency domain beamforming of magnetoencephalographic beta band activity in epilepsy patients with focal cortical dysplasia.

    Science.gov (United States)

    Heers, Marcel; Hirschmann, Jan; Jacobs, Julia; Dümpelmann, Matthias; Butz, Markus; von Lehe, Marec; Elger, Christian E; Schnitzler, Alfons; Wellmer, Jörg

    2014-09-01

    Spike-based magnetoencephalography (MEG) source localization is an established method in the presurgical evaluation of epilepsy patients. Focal cortical dysplasias (FCDs) are associated with focal epileptic discharges of variable morphologies in the beta frequency band in addition to single epileptic spikes. Therefore, we investigated the potential diagnostic value of MEG-based localization of spike-independent beta band (12-30Hz) activity generated by epileptogenic lesions. Five patients with FCD IIB underwent MEG. In one patient, invasive EEG (iEEG) was recorded simultaneously with MEG. In two patients, iEEG succeeded MEG, and two patients had MEG only. MEG and iEEG were evaluated for epileptic spikes. Two minutes of iEEG data and MEG epochs with no spikes as well as MEG epochs with epileptic spikes were analyzed in the frequency domain. MEG oscillatory beta band activity was localized using Dynamic Imaging of Coherent Sources. Intralesional beta band activity was coherent between simultaneous MEG and iEEG recordings. Continuous 14Hz beta band power correlated with the rate of interictal epileptic discharges detected in iEEG. In cases where visual MEG evaluation revealed epileptic spikes, the sources of beta band activity localized within <2cm of the epileptogenic lesion as shown on magnetic resonance imaging. This result held even when visually marked epileptic spikes were deselected. When epileptic spikes were detectable in iEEG but not MEG, MEG beta band activity source localization failed. Source localization of beta band activity has the potential to contribute to the identification of epileptic foci in addition to source localization of visually marked epileptic spikes. Thus, this technique may assist in the localization of epileptic foci in patients with suspected FCD. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. A Cost Benefit Analysis of the Navy Flight Demonstration Team and the U.S. Navy Band

    Science.gov (United States)

    2012-06-01

    calculated by using a percentage of consumer spending at Blue Angels’ airshows. The Blue Angels currently have 16 jets: four single-seat F/A-18 ‘A...determine goodwill, 20% of consumer spending was used to determine consumer surplus. 2. U.S. Navy Band The Navy Band personnel retirement package is...The historical data that we used in determining the Consumer Spending at Blue Angels’ events is derived from the 2009 Northeastern Recreation

  12. Characterizing the dependence of vegetation model parameters on crop structure, incidence angle, and polarization at L-band

    DEFF Research Database (Denmark)

    Wigneron, J-P.; Pardé, M.; Waldteufel, P.

    2004-01-01

    To retrieve soil moisture over vegetation-covered areas from microwave radiometry, it is necessary to account for vegetation effects. At L-band, many retrieval approaches are based on a simple model that relies on two vegetation parameters: the optical depth (tau) and the single-scattering albedo......, wheat, grass, and alfalfa) based on L-band experimental datasets. The results should be useful for developing more accurate forward modeling and retrieval methods over mixed pixels including a variety of vegetation types....

  13. Inter-band coincidences in the superdeformed well of {sup 190}Hg from gammasphere

    Energy Technology Data Exchange (ETDEWEB)

    Crowell, B.; Carpenter, M.P.; Janssens, R.V.F. [and others

    1995-08-01

    Very few experimental observables are ordinarily accessible for superdeformed (SD) states in the A {approximately} 150 and A {approximately} 190 regions. The gamma-decay out of the superdeformed bands usually proceeds directly to the normally deformed states, through highly fragmented pathways, making it difficult to determine the spins, parities and excitation energies of the SD states. The in-band E2 transitions are so collective (2 x 10{sup 3} single-particle units in the A {approximately} 190 region) that it is typically impossible to detect any of the competing M1 and E1 transitions between states in the SD well.

  14. Elastic Band Causing Exfoliation of the Upper Permanent Central Incisors

    Directory of Open Access Journals (Sweden)

    Monica Ghislaine Oliveira Alves

    2015-01-01

    Full Text Available Objective. This study reports a case in which elastic band use culminated in the loss of the incisors. Case Report. An 11-year-old white girl was seen complaining of pain, with purulent discharge and severe tooth mobility. The bone destruction detected radiographically in the region, despite its single location and absence in posterior quadrants of the maxilla and/or mandible, was similar to that observed in Langerhans cell disease. To our surprise, an elastic band involving the midportion of the roots of the two upper central incisors was found during biopsy. The debris was removed and a metal wire was placed in permanent maxillary right and left incisors. The patient was followed up, but no improvement in tooth mobility was observed. Bone loss increased, and internal resorption and root exposure occurred, which culminated in the extraction of permanent maxillary right and left incisors. Conclusion. The present case highlights the fact that professionals sometimes are confronted by anamnestic reports never seen before.

  15. Multifunctional Antenna with Reconfigurable Ultra-Wide Band Characteristics

    Directory of Open Access Journals (Sweden)

    A. Verma

    2017-09-01

    Full Text Available In this paper a multifunctional antenna is presented which offers an ultra-wideband (UWB operation, an UWB operation with two switchable notches and reconfigurable dual-band operation for WiMAX and WLAN applications, respectively. Total seven functions/states could be achieved from a single antenna using an electronic switching. The antenna uses dual slots on the ground plane to provide a wide bandwidth, ranging from 3.1 GHz to 10.6 GHz. U-Shaped slot and C-Shaped printed strip in the ground are used to generate two notches at 3.6 GHz(WiMAX and 5.2 GHz (WLAN/ WiFi bands, respectively. Moreover, four parasitic strips are added in the feed side to make antenna functional at either3.6 GHz or 5.2 GHz or both. Total Five PIN diodes are required to obtain seven operations from the proposed antenna. Seven structures are fabricated and measured to verify the seven states and results are found in good agreement with estimated results obtained from the simulation.

  16. Exploring the Potential of WorldView-2 Red-Edge Band-Based Vegetation Indices for Estimation of Mangrove Leaf Area Index with Machine Learning Algorithms

    Directory of Open Access Journals (Sweden)

    Yuanhui Zhu

    2017-10-01

    Full Text Available To accurately estimate leaf area index (LAI in mangrove areas, the selection of appropriate models and predictor variables is critical. However, there is a major challenge in quantifying and mapping LAI using multi-spectral sensors due to the saturation effects of traditional vegetation indices (VIs for mangrove forests. WorldView-2 (WV2 imagery has proven to be effective to estimate LAI of grasslands and forests, but the sensitivity of its vegetation indices (VIs has been uncertain for mangrove forests. Furthermore, the single model may exhibit certain randomness and instability in model calibration and estimation accuracy. Therefore, this study aims to explore the sensitivity of WV2 VIs for estimating mangrove LAI by comparing artificial neural network regression (ANNR, support vector regression (SVR and random forest regression (RFR. The results suggest that the RFR algorithm yields the best results (RMSE = 0.45, 14.55% of the average LAI, followed by ANNR (RMSE = 0.49, 16.04% of the average LAI, and then SVR (RMSE = 0.51, 16.56% of the average LAI algorithms using 5-fold cross validation (CV using all VIs. Quantification of the variable importance shows that the VIs derived from the red-edge band consistently remain the most important contributor to LAI estimation. When the red-edge band-derived VIs are removed from the models, estimation accuracies measured in relative RMSE (RMSEr decrease by 3.79%, 2.70% and 4.47% for ANNR, SVR and RFR models respectively. VIs derived from red-edge band also yield better accuracy compared with other traditional bands of WV2, such as near-infrared-1 and near-infrared-2 band. Furthermore, the estimated LAI values vary significantly across different mangrove species. The study demonstrates the utility of VIs of WV2 imagery and the selected machine-learning algorithms in developing LAI models in mangrove forests. The results indicate that the red-edge band of WV2 imagery can help alleviate the saturation

  17. Band profiles of Mott-insulator/band-insulator heterointerfaces revealed by photocurrent and electromodulation spectroscopies

    Science.gov (United States)

    Nakamura, Masao

    2011-03-01

    Heterointerfaces of Mott insulators provide a good laboratory to explore unprecedented electronic states induced by the strong electron correlation. Although a number of intriguing phenomena have been reported so far, their fundamental origins have not been fully addressed yet. This is partly because the interface band profile, which is one of the most basic knowledge to understand the interface electronic states, is still left to be unveiled. In this study, we have investigated in detail the interface band profiles of Mott insulators employing photocurrent and electromodulation spectroscopies as well as the conventional current-voltage and capacitance-voltage characterizations. We chose p -type (LaMn O3 and La 2 Cu O4) and n -type (SrMn O3 and Sm 2 Cu O4) as the Mott insulators and these are epitaxially connected to Nb doped SrTi O3 (electron-doped band insulator). The photocurrent action spectra for these heterojunctions showed negligibly-small band reconstruction as well as the existence of band bending and discontinuity in the Mott insulators, which are of no salient discrepancy with the rigid-band picture valid in the interface of conventional semiconductors~. However, the electromodulation spectra clearly indicate the band reconstruction in the Mott insulators~. The results mean that the rigid-band picture is valid in the low carrier-density regime even in Mott-insulator/band-insulator interfaces, but the intentional charge modulation leads the electron correlation effect in the Mott insulators. This work was done in collaboration with A. Sawa, J. Fujioka, M. Kawasaki and Y. Tokura. I acknowledge the support from Japan Society for the Promotion of Science (JSPS) through its ``Funding Program for World-Leading Innovative R&D on Science and Technology (FIRST Program)''.

  18. Transistors - From Point Contact to Single Electron

    Indian Academy of Sciences (India)

    development of the energy band theory of solids by Wilson. ... Davydov developed bis theory independently. All these theories had shortcomings as pointed out by Sab. The correct theory of metal-semiconductor diodes based on thermionic emission of majority carriers .... watches and other portable consumer applications.

  19. Isoelectric focusing purity criteria and 1H NMR detectable spectroscopic heterogeneity in the major isolated monomer hemoglobins from Glycera dibranchiata

    International Nuclear Information System (INIS)

    Constantinidis, I.; Satterlee, J.D.

    1987-01-01

    Three major monomeric hemoglobins have been isolated from the erythrocytes of Glycera dibranchiata. Their importance to structure-function studies of heme proteins lies in the fact that they have been shown to possess an exceptional amino acid substitution. In these proteins, the E-7 position is occupied by leucine rather than the more common distal histidine. This substitution alters the polarity of the heme ligand binding environment compared to myoglobin. Due to this, the G. dibranchiata monomer hemoglobins are attracting much attention. However, until now no purity criterion has been developed. Here the authors demonstrate that, for all of the Glycera momomer hemoglobins, multiple line patterns are shown on high-voltage isoelectric focusing (IEF) gels. Most of these lines are shown to be a consequence of heme-related phenomena and can be understood on the basis of changes in oxidation and ligation state of the heme iron. The multiple line pattern does not indicate significant impurities in the monomer hemoglobin preparation. The multiple line patterns on IEF gels disappear when gels of the apoproteins alone are focused. Single bands occur in this case for all of the monomer hemoglobins except component II, which displays two bands, one major and one minor. The minor band is found to be a modified apoprotein form. It is sensitive to apoprotein handling prior to focusing and depends upon whether the IEF gel is prefocused or not. From this analysis, IEF is shown to be a valuable purity criterion, and the purity of our monomer hemoglobin component II preparation is 97% one globin. The NMR results show that two types of spectroscopic heterogeneity are also present in component II, and these are unrelated to the protein purity

  20. High-Power Fiber Lasers Using Photonic Band Gap Materials

    Science.gov (United States)

    DiDomenico, Leo; Dowling, Jonathan

    2005-01-01

    High-power fiber lasers (HPFLs) would be made from photonic band gap (PBG) materials, according to the proposal. Such lasers would be scalable in the sense that a large number of fiber lasers could be arranged in an array or bundle and then operated in phase-locked condition to generate a superposition and highly directed high-power laser beam. It has been estimated that an average power level as high as 1,000 W per fiber could be achieved in such an array. Examples of potential applications for the proposed single-fiber lasers include welding and laser surgery. Additionally, the bundled fibers have applications in beaming power through free space for autonomous vehicles, laser weapons, free-space communications, and inducing photochemical reactions in large-scale industrial processes. The proposal has been inspired in part by recent improvements in the capabilities of single-mode fiber amplifiers and lasers to produce continuous high-power radiation. In particular, it has been found that the average output power of a single strand of a fiber laser can be increased by suitably changing the doping profile of active ions in its gain medium to optimize the spatial overlap of the electromagnetic field with the distribution of active ions. Such optimization minimizes pump power losses and increases the gain in the fiber laser system. The proposal would expand the basic concept of this type of optimization to incorporate exploitation of the properties (including, in some cases, nonlinearities) of PBG materials to obtain power levels and efficiencies higher than are now possible. Another element of the proposal is to enable pumping by concentrated sunlight. Somewhat more specifically, the proposal calls for exploitation of the properties of PBG materials to overcome a number of stubborn adverse phenomena that have impeded prior efforts to perfect HPFLs. The most relevant of those phenomena is amplified spontaneous emission (ASE), which causes saturation of gain and power

  1. Ultra-Low-Noise W-Band MMIC Detector Modules

    Science.gov (United States)

    Gaier, Todd C.; Samoska, Lorene A.; Kangaslahti, Pekka P.; Van Vinkle, Dan; Tantawi, Sami; Fox, John; Church, Sarah E.; Lau, Jusy M.; Sieth, Matthew M.; Voll, Patricia E.; hide

    2010-01-01

    A monolithic microwave integrated circuit (MMIC) receiver can be used as a building block for next-generation radio astronomy instruments that are scalable to hundreds or thousands of pixels. W-band (75-110 GHz) low-noise receivers are needed for radio astronomy interferometers and spectrometers, and can be used in missile radar and security imagers. These receivers need to be designed to be mass-producible to increase the sensitivity of the instrument. This innovation is a prototyped single-sideband MMIC receiver that has all the receiver front-end functionality in one small and planar module. The planar module is easy to assemble in volume and does not require tuning of individual receivers. This makes this design low-cost in large volumes.

  2. Weyl states and Fermi arcs in parabolic bands

    Science.gov (United States)

    Doria, Mauro M.; Perali, Andrea

    2017-07-01

    Weyl fermions are shown to exist inside a parabolic band in a single electronic layer, where the kinetic energy of carriers is given by the non-relativistic Schroedinger equation. There are Fermi arcs as a direct consequence of the folding of a ring-shaped Fermi surface inside the first Brillouin zone. Our results stem from the decomposition of the kinetic energy into the sum of the square of the Weyl state, the coupling to the local magnetic field and the Rashba interaction. The Weyl fermions break the space and time reflection symmetries present in the kinetic energy, thus allowing for the onset of a weak three-dimensional magnetic field around the layer. This field brings topological stability to the current-carrying states through a Chern number. In the special limit for which the Weyl state becomes gapless, this magnetic interaction is shown to be purely attractive, thus suggesting the onset of a superconducting condensate of zero helicity states.

  3. Polycrystalline ZrTe{sub 5} Parameterized as a Narrow Band Gap Semiconductor for Thermoelectric Performance.

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Samuel A.; Witting, Ian; Aydemir, Umut; Peng, Lintao; Rettie, Alex; Gorai, Prashun; Chung, Duck Young; Kanatzidis, Mercouri G.; Grayson, Matthew A.; Stevanovic, Vladan; Toberer, Eric S.; Snyder, G. Jeffery

    2018-01-24

    The transition-metal pentatellurides HfTe5 and ZrTe5 have been studied for their exotic transport properties with much debate over the transport mechanism, band gap, and cause of the resistivity behavior, including a large low-temperature resistivity peak. Single crystals grown by the chemical-vapor-transport method have shown an n-p transition of the Seebeck coefficient at the same temperature as a peak in the resistivity. We show that behavior similar to that of single crystals can be observed in iodine-doped polycrystalline samples but that undoped polycrystalline samples exhibit drastically different properties: they are p type over the entire temperature range. Additionally, the thermal conductivity for polycrystalline samples is much lower, 1.5 Wm-1 K-1, than previously reported for single crystals. It is found that the polycrystalline ZrTe5 system can be modeled as a simple semiconductor with conduction and valence bands both contributing to transport, separated by a band gap of 20 meV. This model demonstrates to first order that a simple two-band model can explain the transition from n- to p-type behavior and the cause of the anomalous resistivity peak. Combined with the experimental data, the two-band model shows that carrier concentration variation is responsible for differences in behavior between samples. Using the twoband model, the thermoelectric performance at different doping levels is predicted, finding zT =0.2 and 0.1 for p and n type, respectively, at 300 K, and zT= 0.23 and 0.32 for p and n type at 600 K. Given the reasonably high zT that is comparable in magnitude for both n and p type, a thermoelectric device with a single compound used for both legs is feasible.

  4. UWB Filtering Power Divider with Two Narrow Notch-bands and Wide Stop-band

    Science.gov (United States)

    Wei, Feng; Wang, Xin-Yi; Zou, Xin Tong; Shi, Xiao Wei

    2017-12-01

    A compact filtering ultra-wideband (UWB) microstrip power divider (PD) with two sharply rejected notch-bands and wide stopband is analyzed and designed in this paper. The proposed UWB PD is based on a conventional Wilkinson power divider, while two stub loaded resonators (SLRs) are coupled into two symmetrical output ports to achieve a bandpass filtering response. The simplified composite right/left-handed (SCRLH) resonators are employed to generate the dual notched bands. Defected ground structure (DGS) is introduced to improve the passband performance. Good insertion/return losses, isolation and notch-band rejection are achieved as demonstrated in both simulation and experiment.

  5. Correlation functions and susceptibilities of photonics band gap reservoirs

    International Nuclear Information System (INIS)

    Konopka, M.

    1998-01-01

    We investigate quantum statistical properties of photonic band gap reservoirs in terms of correlation functions and susceptibilities in time and spectral domains. Typical features are oscillations of the time-dependent correlation functions and susceptibilities. This is because photonic bad gap reservoirs are intrinsically non-Markovian reservoirs. The results help us to understand better how intrinsic quantum-statistical properties of a reservoir influence dynamics of an atom interacting with this reservoir. Boundary conditions influence time and spectral properties of the electromagnetic field. This well-known fact has a great importance in optics and generally in electromagnetism. Specific examples are resonators used in laser technique and cavity electrodynamics. In quantum optics high-Q micro cavities are used for single-atom experiments when an atom can interact in a coherent way with an electromagnetic field which has its mode structure totally different from those in free space. In particular, interaction of an (effectively) two-level atom with a single-mode cavity field was observed in the region of microwaves (with the wavelength about 1 cm). In 1987 Yablonovitch and John independently proposed that certain periodic dielectric structures can present forbidden frequency gaps (or pseudo gaps in partially disordered structures) for transverse modes. Such periodic structures were named 'photonic band structures' or 'photonic crystals', in analogy with electronic crystals which also have a (forbidden) gap for electronic energy. For true photonic crystals the basic property of blocking electromagnetic wave propagation must be fulfilled for all waves within some frequency range, i.e. for all wavevector and polarization directions

  6. Investigations of the Band Structure and Morphology of Nanostructured Surfaces

    Science.gov (United States)

    Knox, Kevin R.

    2011-12-01

    In this dissertation, I examine the electronic structure of two very different types of two-dimensional systems: valence band electrons in single layer graphene and electronic states created at the vacuum interface of single crystal copper surfaces. The characteristics of both electronic systems depend intimately on the morphology of the surfaces they inhabit. Thus, in addition to discussing the respective band structures of these systems, a significant portion of this dissertation will be devoted to measurements of the surface morphology of these systems. Free-standing exfoliated monolayer graphene is an ultra-thin flexible membrane and, as such, is known to exhibit large out-of-plane deformation due to substrate and adsorbate interaction as well as thermal vibrations and, possibly, intrinsic buckling. Such crystal deformation is known to limit mobility and increase local chemical reactivity. Additionally, deformations present a measurement challenge to researchers wishing to determine the band structure by angle-resolved photoemission since they limit electron coherence in such measurements. In this dissertation, I present low energy electron microscopy and micro probe diffraction measurements, which are used to image and characterize corrugation in SiO2-supported and suspended exfoliated graphene at nanometer length scales. Diffraction line-shape analysis reveals quantitative differences in surface roughness on length scales below 20 nm which depend on film thickness and interaction with the substrate. Corrugation decreases with increasing film thickness, reflecting the increased stiffness of multilayer films. Specifically, single-layer graphene shows a markedly larger short range roughness than multilayer graphene. Due to the absence of interactions with the substrate, suspended graphene displays a smoother morphology and texture than supported graphene. A specific feature of suspended single-layer films is the dependence of corrugation on both adsorbate load

  7. Design and Realization of a Planar Ultrawideband Antenna with Notch Band at 3.5 GHz

    Science.gov (United States)

    2014-01-01

    A small antenna with single notch band at 3.5 GHz is designed for ultrawideband (UWB) communication applications. The fabricated antenna comprises a radiating monopole element and a perfectly conducting ground plane with a wide slot. To achieve a notch band at 3.5 GHz, a parasitic element has been inserted in the same plane of the substrate along with the radiating patch. Experimental results shows that, by properly adjusting the position of the parasitic element, the designed antenna can achieve an ultrawide operating band of 3.04 to 11 GHz with a notched band operating at 3.31–3.84 GHz. Moreover, the proposed antenna achieved a good gain except at the notched band and exhibits symmetric radiation patterns throughout the operating band. The prototype of the proposed antenna possesses a very compact size and uses simple structures to attain the stop band characteristic with an aim to lessen the interference between UWB and worldwide interoperability for microwave access (WiMAX) band. PMID:25133245

  8. Design and Realization of a Planar Ultrawideband Antenna with Notch Band at 3.5 GHz

    Directory of Open Access Journals (Sweden)

    Rezaul Azim

    2014-01-01

    Full Text Available A small antenna with single notch band at 3.5 GHz is designed for ultrawideband (UWB communication applications. The fabricated antenna comprises a radiating monopole element and a perfectly conducting ground plane with a wide slot. To achieve a notch band at 3.5 GHz, a parasitic element has been inserted in the same plane of the substrate along with the radiating patch. Experimental results shows that, by properly adjusting the position of the parasitic element, the designed antenna can achieve an ultrawide operating band of 3.04 to 11 GHz with a notched band operating at 3.31–3.84 GHz. Moreover, the proposed antenna achieved a good gain except at the notched band and exhibits symmetric radiation patterns throughout the operating band. The prototype of the proposed antenna possesses a very compact size and uses simple structures to attain the stop band characteristic with an aim to lessen the interference between UWB and worldwide interoperability for microwave access (WiMAX band.

  9. Methods for Analyzing Pathways through a Physics Major

    OpenAIRE

    Aiken, John M.; Caballero, Marcos D.

    2016-01-01

    Physics Education Research frequently investigates what students studying physics do on small time scales (e.g. single courses, observations within single courses), or post-education time scales (e.g., what jobs do physics majors get?) but there is little research into how students get from the beginning to the end of a physics degree. Our work attempts to visualize students paths through the physics major, and quantitatively describe the students who take physics courses, receive physics deg...

  10. Band head spin assignment of superdeformed bands in 133Pr using two-parameter formulae

    Science.gov (United States)

    Sharma, Honey; Mittal, H. M.

    2018-03-01

    The two-parameter formulae viz. the power index formula, the nuclear softness formula and the VMI model are adopted to accredit the band head spin (I0) of four superdeformed rotational bands in 133Pr. The technique of least square fitting is used to accredit the band head spin for four superdeformed rotational bands in 133Pr. The root mean deviation among the computed transition energies and well-known experimental transition energies are attained by extracting the model parameters from the two-parameter formulae. The determined transition energies are in excellent agreement with the experimental transition energies, whenever exact spins are accredited. The power index formula coincides well with the experimental data and provides minimum root mean deviation. So, the power index formula is more efficient tool than the nuclear softness formula and the VMI model. The deviation of dynamic moment of inertia J(2) against the rotational frequency is also examined.

  11. Band connectivity for topological quantum chemistry: Band structures as a graph theory problem

    Science.gov (United States)

    Bradlyn, Barry; Elcoro, L.; Vergniory, M. G.; Cano, Jennifer; Wang, Zhijun; Felser, C.; Aroyo, M. I.; Bernevig, B. Andrei

    2018-01-01

    The conventional theory of solids is well suited to describing band structures locally near isolated points in momentum space, but struggles to capture the full, global picture necessary for understanding topological phenomena. In part of a recent paper [B. Bradlyn et al., Nature (London) 547, 298 (2017), 10.1038/nature23268], we have introduced the way to overcome this difficulty by formulating the problem of sewing together many disconnected local k .p band structures across the Brillouin zone in terms of graph theory. In this paper, we give the details of our full theoretical construction. We show that crystal symmetries strongly constrain the allowed connectivities of energy bands, and we employ graph theoretic techniques such as graph connectivity to enumerate all the solutions to these constraints. The tools of graph theory allow us to identify disconnected groups of bands in these solutions, and so identify topologically distinct insulating phases.

  12. Diagnosis and management of early gastric band slip after laparoscopic adjustable gastric banding

    Directory of Open Access Journals (Sweden)

    Mehmet Sertkaya

    2016-05-01

    Full Text Available Laparoscopic adjustable gastric banding (LAGB used to be a very popular bariatric procedure at a certain time for the treatment of obesity as it has many advantages and is associated with low morbidity and mortality rates. Complications are often late and are rarely seen by general surgeons due to the limited number of patients, and physicians should be aware of the symptoms. We present a case of a 40-year-old female patient who underwent LAGB and was admitted for a huge gastric pouch dilatation on postoperative day 5. She had a history of food consumption on the fourth day after surgery. She was diagnosed with early gastric band slippage (EGBS. The band was repositioned and gastrogastric sutures were placed to prevent reprolapse of the band. The EGBS is an immediate postoperative complication. Diagnosis of EGBS can be made with oral contrast X-ray studies, and surgical intervention is necessary.

  13. Electronic pairing mechanism due to band modification in a two-band model: Tc evaluation

    International Nuclear Information System (INIS)

    Mizia, J.; Gorski, G.; Traa, M.R.M.J.

    1997-01-01

    Following the electronic model developed by us previously (Mizia and Romanowski, Mizia) we estimate the superconducting transition temperature in a simple electronic two-band model for materials characterized by a broad superconducting band and a narrow level within the same energy range. A large electron deformation coupling constant and large electron correlation effects are assumed. It is shown that high-temperature superconductivity is entirely possible within a range of reasonable electronic parameters. This model does not assume any artificial interactions to obtain a negative pairing potential. Instead, the negative part of the electronic interaction potential comes from the modification of the electron dispersion relation with growing number of superconducting pairs. Such a modification is possible in soft electronic systems, i.e. in systems partial to band modification due to large internal stresses, strong electronic correlation effects and broad band narrow level charge transfer during the superconducting transition. (orig.)

  14. Resonant interaction of a single atom with single photons from a down-conversion source

    International Nuclear Information System (INIS)

    Schuck, C.; Rohde, F.; Piro, N.; Almendros, M.; Huwer, J.; Mitchell, M. W.; Hennrich, M.; Haase, A.; Dubin, F.; Eschner, J.

    2010-01-01

    We observe the interaction of a single trapped calcium ion with single photons produced by a narrow-band, resonant down-conversion source [A. Haase et al., Opt. Lett. 34, 55 (2009)], employing a quantum jump scheme. Using the temperature dependence of the down-conversion spectrum and the tunability of the narrow source, absorption of the down-conversion photons is quantitatively characterized.

  15. Assessment of S-NPP VIIRS band-to-band registration using Earth-scene features

    Science.gov (United States)

    Link, Daniel; Wang, Zhipeng; Xiong, Xiaoxiong

    2017-09-01

    The Visible Infrared Imaging Radiometer Suite (VIIRS) is currently operating onboard the Suomi National Polarorbiting Partnership (S-NPP) spacecraft. VIIRS records Earth imagery with spectral bands ranging from 0.4 to 12.2 micrometers at a combination of resolutions. Five imaging bands (I1-5) have a 375 m spatial resolution at nadir, which is half of the 750 m resolution of the 16 moderate resolution bands (M1-16). These bands are mounted according to their wavelengths at three separate Focal Plane Assemblies (FPA). The proper spatial registration among imaging bands is required to create multi-spectral images and analyses. Measurement of the band-to-band registration (BBR) is a determination of how well these bands are coincident. Using an external target such as the moon has proven to be a valid method and has been thoroughly investigated using VIIRS raw data record (RDR). Calibrated VIIRS radiometric data has been investigated using normalized mutual information (NMI) for BBR and shown stable results, by focusing on high-contrast shoreline sites. However, these results focus on a relatively small number of observations. We have previously reported analyses using earth-scene targets to determine BBR for MODIS instruments. This approach focuses on an African Desert site with high contrast spots generated through agricultural pivot irrigation. Using the near-daily observations provided by the VIIRS instrument, we investigate a large data set and track the BBR stability over the VIIRS mission. We discuss our results and compare them with prelaunch measurements and design specifications.

  16. Transport in bilayer and trilayer graphene: band gap engineering and band structure tuning

    Science.gov (United States)

    Zhu, Jun

    2014-03-01

    Controlling the stacking order of atomically thin 2D materials offers a powerful tool to control their properties. Linearly dispersed bands become hyperbolic in Bernal (AB) stacked bilayer graphene (BLG). Both Bernal (ABA) and rhombohedral (ABC) stacking occur in trilayer graphene (TLG), producing distinct band structures and electronic properties. A symmetry-breaking electric field perpendicular to the sample plane can further modify the band structures of BLG and TLG. In this talk, I will describe our experimental effort in these directions using dual-gated devices. Using thin HfO2 film deposited by ALD as gate dielectric, we are able to apply large displacement fields D > 6 V/nm and observe the opening and saturation of the field-induced band gap Eg in bilayer and ABC-stacked trilayer graphene, where the conduction in the mid gap changes by more than six decades. Its field and temperature dependence highlights the crucial role played by Coulomb disorder in facilitating hopping conduction and suppressing the effect of Eg in the tens of meV regime. In contrast, mid-gap conduction decreases with increasing D much more rapidly in clean h-BN dual-gated devices. Our studies also show the evolution of the band structure in ABA-stacked TLG, in particular the splitting of the Dirac-like bands in large D field and the signatures of two-band transport at high carrier densities. Comparison to theory reveals the need for more sophisticated treatment of electronic screening beyond self-consistent Hartree calculations to accurately predict the band structures of trilayer graphene and graphenic materials in general.

  17. Tri Band Dual Polarized Patch Antenna System For Next Generation Cellular Networks

    Directory of Open Access Journals (Sweden)

    Syed Daniyal Ali Shah

    2017-12-01

    Full Text Available In fifth generation networks much emphasis is given to reduce the handset and base station sizes while incorporating even more features for ubiquitous connectivity. Polarization diversity is one of the methods in which a single multi-polarized antenna brings the advantages of antenna diversity. The multiband handset antennas can be made dual-polarized for improved compensation of fading effects of propagation environment especially in terrestrial bands. This paper focuses on the outcomes of the development of a horizontal and vertical polarized patch antenna scheme that operates on 3 bands 900 MHz 1.8 GHz and 2.4 GHz. The antenna system is tested for gain directivity reflection loss polarization radiation pattern and other parameters. The results are published and found are found to satisfy the requirements of cellular and data communication networks in the specified bands.

  18. Agricultural Land Cover from Multitemporal C-Band SAR Data

    Science.gov (United States)

    Skriver, H.

    2013-12-01

    Henning Skriver DTU Space, Technical University of Denmark Ørsteds Plads, Building 348, DK-2800 Lyngby e-mail: hs@space.dtu.dk Problem description This paper focuses on land cover type from SAR data using high revisit acquisitions, including single and dual polarisation and fully polarimetric data, at C-band. The data set were acquired during an ESA-supported campaign, AgriSAR09, with the Radarsat-2 system. Ground surveys to obtain detailed land cover maps were performed during the campaign. Classification methods using single- and dual-polarisation data, and fully polarimetric data are used with multitemporal data with short revisit time. Results for airborne campaigns have previously been reported in Skriver et al. (2011) and Skriver (2012). In this paper, the short revisit satellite SAR data will be used to assess the trade-off between polarimetric SAR data and data as single or dual polarisation SAR data. This is particularly important in relation to the future GMES Sentinel-1 SAR satellites, where two satellites with a relatively wide swath will ensure a short revisit time globally. Questions dealt with are: which accuracy can we expect from a mission like the Sentinel-1, what is the improvement of using polarimetric SAR compared to single or dual polarisation SAR, and what is the optimum number of acquisitions needed. Methodology The data have sufficient number of looks for the Gaussian assumption to be valid for the backscatter coefficients for the individual polarizations. The classification method used for these data is therefore the standard Bayesian classification method for multivariate Gaussian statistics. For the full-polarimetric cases two classification methods have been applied, the standard ML Wishart classifier, and a method based on a reversible transform of the covariance matrix into backscatter intensities. The following pre-processing steps were performed on both data sets: The scattering matrix data in the form of SLC products were

  19. Development of softcopy environment for primary color banding visibility assessment

    Science.gov (United States)

    Min, Byungseok; Pizlo, Zygmunt; Allebach, Jan P.

    2008-01-01

    Fine-pitch banding is one of the most unwanted artifacts in laser electrophotographic (EP) printers. It is perceived as a quasiperiodic fluctuation in the process direction. Therefore, it is essential for printer vendors to know how banding is perceived by humans in order to improve print quality. Monochrome banding has been analyzed and assessed by many researchers; but there is no literature that deals with the banding of color laser printers as measured from actual prints. The study of color banding is complicated by the fact that the color banding signal is physically defined in a three-dimensional color space, while banding perception is described in a one-dimensional sense such as more banding or less banding. In addition, the color banding signal arises from the independent contributions of the four primary colorant banding signals. It is not known how these four distinct signals combine to give rise to the perception of color banding. In this paper, we develop a methodology to assess the banding visibility of the primary colorant cyan based on human visual perception. This is our first step toward studying the more general problem of color banding in combinations of two or more colorants. According to our method, we print and scan the cyan test patch, and extract the banding profile as a one dimensional signal so that we can freely adjust the intensity of banding. Thereafter, by exploiting the pulse width modulation capability of the laser printer, the extracted banding profile is used to modulate a pattern consisting of periodic lines oriented in the process direction, to generate extrinsic banding. This avoids the effect of the halftoning algorithm on the banding. Furthermore, to conduct various banding assessments more efficiently, we also develop a softcopy environment that emulates a hardcopy image on a calibrated monitor, which requires highly accurate device calibration throughout the whole system. To achieve the same color appearance as the hardcopy

  20. A Compact Tri-Band Bandpass Filter with High Out-of-Band Rejection

    Directory of Open Access Journals (Sweden)

    M. Abdul-Niby

    2017-08-01

    Full Text Available This paper presents a planar tri-band bandpass filter with high out-of-band rejection over a wide band. The filter is based on two pairs of λ/4 resonators embedded inside an open loop ring resonator without any size increase, where each pair of resonators are electromagnetically coupled to each other and the feedlines. This results in the excitations of passbands, where the first passband is generated by the open loop resonators. The second and the third passbands are excited by λ/4 resonators. The proposed technique provides sufficient degrees of freedom to control the center frequency and bandwidth of the three passbands independently. In addition, the six transmission zeros created around the passbands results in a tri-band filter with high selectivity, sharp 3 dB cut-off frequency, high isolation, low passband insertion-loss and high out-of-band harmonic rejection across an ultra-broadband frequency range up to 17 GHz. The proposed technique has the ability to switch from triple to dual band by removing one pair of the inner resonators. Design methodology and simulation results of the filter are provided.