WorldWideScience

Sample records for single-mode operation favorable

  1. Single mode operation of a TEA CO2 laser

    International Nuclear Information System (INIS)

    Wada, Kazuhiro; Tunawaki, Yoshiaki; Yamanaka, Masanobu.

    1993-01-01

    Single mode operation of a TEA CO 2 laser was performed by using an optical system of Fox-Smith type. Laser beam was taken out from the cavity by using a beam splitter, and was reflected by a mirror back to the cavity. By inserting a Fabry-Perot etalon between the splitter and the mirror, beat of laser pulses can be removed completly. (author)

  2. Mode coupling in hybrid square-rectangular lasers for single mode operation

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Xiu-Wen; Huang, Yong-Zhen, E-mail: yzhuang@semi.ac.cn; Yang, Yue-De; Xiao, Jin-Long; Weng, Hai-Zhong; Xiao, Zhi-Xiong [State Key Laboratory on Integrated Optoelectronics, Institute of Semiconductors and University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100083 (China)

    2016-08-15

    Mode coupling between a square microcavity and a Fabry-Pérot (FP) cavity is proposed and demonstrated for realizing single mode lasers. The modulations of the mode Q factor as simulation results are observed and single mode operation is obtained with a side mode suppression ratio of 46 dB and a single mode fiber coupling loss of 3.2 dB for an AlGaInAs/InP hybrid laser as a 300-μm-length and 1.5-μm-wide FP cavity connected to a vertex of a 10-μm-side square microcavity. Furthermore, tunable single mode operation is demonstrated with a continuous wavelength tuning range over 10 nm. The simple hybrid structure may shed light on practical applications of whispering-gallery mode microcavities in large-scale photonic integrated circuits and optical communication and interconnection.

  3. Single mode operation of a tea CO2 laser by a CW CO2 laser radiation injection

    International Nuclear Information System (INIS)

    Silakhori, K.; Soltanmoradi, F.; Behjat, A.; Montazerghaem, M.; Sadr, R.

    2005-01-01

    In this research work, single mode operation based on injection of a CW laser beam into TEA CO 2 laser cavity has been demonstrated. The technique has vast applications in research programs for laser spectroscopy and optical pumping. The observed smooth pulse shapes indicated that the system is operating in a single mode of operation, where no additional PZT mounted elements or other cavity stabilizing devices have been used. In addition, it have been observed that the output energy has not been reduced when the laser was operating in a single mode of operation, compared with the case when the laser is operating in the multi-mode regime

  4. Single mode operation in a pulsed Ti:sapphire laser oscillator with a grazing-incidence four-mirror cavity

    CERN Document Server

    Ko, D K; Binks, D J; Gloster, L A W; King, T A

    1998-01-01

    We demonstrate stable single mode operation in a pulsed Ti:sapphire laser oscillator with a novel grazing-incidence four-mirror coupled cavity. This cavity consists of a grating, a gain medium, and four mirrors and, therefore, has a four-arm interferometer configuration. Through the interferometric effect, we could suppress the adjacent modes and obtain stable single mode operation with a bandwidth of < 200 MHz. We also have developed a general analysis of the laser modes and the threshold conditions for configuration and the experimental results agree well with the theoretical predictions.

  5. The combination of directional outputs and single-mode operation in circular microdisk with broken PT symmetry.

    Science.gov (United States)

    Song, Qinghai; Li, Jiankai; Sun, Wenzhao; Zhang, Nan; Liu, Shuai; Li, Meng; Xiao, Shumin

    2015-09-21

    Monochromaticity and directionality are two key characteristics of lasers. However, the combination of directional emission and single-mode operation is quite challenging, especially for the on-chip devices. Here we propose a microdisk laser with single-mode operation and directional emissions by exploiting the recent developments associated with parity-time (PT) symmetry. This is accomplished by introducing one-dimensional periodic gain and loss into a circular microdisk, which induces a coupling between whispering gallery modes with different radial numbers. The lowest threshold mode is selected at the positions with least initial wavelength difference. And the directional emissions are formed by the introduction of additional grating vectors by the periodic distribution of gain and loss regions. We believe this research will impact the practical applications of on-chip microdisk lasers.

  6. Stable Single-Mode Operation of Distributed Feedback Quantum Cascade Laser by Optimized Reflectivity Facet Coatings.

    Science.gov (United States)

    Wang, Dong-Bo; Zhang, Jin-Chuan; Cheng, Feng-Min; Zhao, Yue; Zhuo, Ning; Zhai, Shen-Qiang; Wang, Li-Jun; Liu, Jun-Qi; Liu, Shu-Man; Liu, Feng-Qi; Wang, Zhan-Guo

    2018-02-02

    In this work, quantum cascade lasers (QCLs) based on strain compensation combined with two-phonon resonance design are presented. Distributed feedback (DFB) laser emitting at ~ 4.76 μm was fabricated through a standard buried first-order grating and buried heterostructure (BH) processing. Stable single-mode emission is achieved under all injection currents and temperature conditions without any mode hop by the optimized antireflection (AR) coating on the front facet. The AR coating consists of a double layer dielectric of Al 2 O 3 and Ge. For a 2-mm laser cavity, the maximum output power of the AR-coated DFB-QCL was more than 170 mW at 20 °C with a high wall-plug efficiency (WPE) of 4.7% in a continuous-wave (CW) mode.

  7. Semi-guiding high-aspect-ratio core (SHARC) fiber providing single-mode operation and an ultra-large core area in a compact coilable package

    Science.gov (United States)

    Rockwell, David A.; Shkunov, Vladimir V.; Marciante, John R.

    2011-07-01

    A new class of optical fiber is presented that departs from the circular-core symmetry common to conventional fibers. By using a high-aspect-ratio (~30:1) rectangular core, the mode area can be significantly expanded well beyond 10,000 μm2. Moreover, by also specifying a very small refractive-index step at the narrow core edges, the core becomes ``semi-guiding,'' i.e. it guides in the narrow dimension and is effectively un-guiding in the wide mm-scale dimension. The mode dependence of the resulting Fresnel leakage loss in the wide dimension strongly favors the fundamental mode, promoting single-mode operation. Since the modal loss ratios are independent of mode area, this core structure offers nearly unlimited scalability. The implications of using such a fiber in fiber laser and amplifier systems are also discussed.

  8. Geometric characterization of separability and entanglement in pure Gaussian states by single-mode unitary operations

    International Nuclear Information System (INIS)

    Adesso, Gerardo; Giampaolo, Salvatore M.; Illuminati, Fabrizio

    2007-01-01

    We present a geometric approach to the characterization of separability and entanglement in pure Gaussian states of an arbitrary number of modes. The analysis is performed adapting to continuous variables a formalism based on single subsystem unitary transformations that has been recently introduced to characterize separability and entanglement in pure states of qubits and qutrits [S. M. Giampaolo and F. Illuminati, Phys. Rev. A 76, 042301 (2007)]. In analogy with the finite-dimensional case, we demonstrate that the 1xM bipartite entanglement of a multimode pure Gaussian state can be quantified by the minimum squared Euclidean distance between the state itself and the set of states obtained by transforming it via suitable local symplectic (unitary) operations. This minimum distance, corresponding to a, uniquely determined, extremal local operation, defines an entanglement monotone equivalent to the entropy of entanglement, and amenable to direct experimental measurement with linear optical schemes

  9. Single-mode distributed feedback laser operation with no dependence on the morphology of the gain medium

    Energy Technology Data Exchange (ETDEWEB)

    Umar, Muhammad [Department of Energy Systems Research, Ajou University, Suwon (Korea, Republic of); Min, Kyungtaek [Department of Energy Systems Research, Ajou University, Suwon (Korea, Republic of); Inter-university Semiconductor Research Center, Seoul National University (Korea, Republic of); Jeon, Heonsu [Department of Physics and Astronomy, Seoul National University (Korea, Republic of); Kim, Sunghwan [Department of Energy Systems Research, Ajou University, Suwon (Korea, Republic of); Department of Physics, Ajou University, Suwon (Korea, Republic of)

    2017-06-15

    Organic distributed feedback (DFB) lasers can be useful photonic tools for biological applications where the roles of organic materials are important, because highly coherent single mode emission with broad tuning range can be obtained. However, the formulaic structures of organic lasers, and the uses of gain media as resonators themselves, are not suitable for inducing laser emission from irregular shaped gain media, such as dye-staining cells and tissues. Here, we report a reusable photonic template comprising an exceedingly thin and discrete titanium dioxide (TiO{sub 2}) layer on a one-dimensional (1D) quartz grating to induce single mode DFB lasing from a variety of states of optical gain media. Using the same template, the external gain media of optically thick and thin casted film, liquid, and a free-standing thick film reveal single mode lasing with reliable performance. Numerical simulations demonstrate that the 25-nm thick TiO{sub 2} disconnected grating lines support a spatially confined DFB mode in the vertical direction, even under no index difference between superstrate and substrate. Additionally, not using the typical waveguide gain layer promises high sensitivity and detection limit in refractometric sensing. These results suggest that the photonic structure may serve as a versatile sensing platform for bioapplications. (copyright 2017 by WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  10. Single-Mode VCSELs

    Science.gov (United States)

    Larsson, Anders; Gustavsson, Johan S.

    The only active transverse mode in a truly single-mode VCSEL is the fundamental mode with a near Gaussian field distribution. A single-mode VCSEL produces a light beam of higher spectral purity, higher degree of coherence and lower divergence than a multimode VCSEL and the beam can be more precisely shaped and focused to a smaller spot. Such beam properties are required in many applications. In this chapter, after discussing applications of single-mode VCSELs, we introduce the basics of fields and modes in VCSELs and review designs implemented for single-mode emission from VCSELs in different materials and at different wavelengths. This includes VCSELs that are inherently single-mode as well as inherently multimode VCSELs where higher-order modes are suppressed by mode selective gain or loss. In each case we present the current state-of-the-art and discuss pros and cons. At the end, a specific example with experimental results is provided and, as a summary, the most promising designs based on current technologies are identified.

  11. Single-mode optical fibres

    CERN Document Server

    Cancellieri, G

    1991-01-01

    This book describes signal propagation in single-mode optical fibres for telecommunication applications. Such description is based on the analysis of field propagation, considering waveguide properties and also some of the particular characteristics of the material fibre. The book covers such recent advances as, coherent transmissions; optical amplification; MIR fibres; polarization maintaining; polarization diversity and photon counting.

  12. Single-mode biological distributed feedback laser

    DEFF Research Database (Denmark)

    Vannahme, Christoph; Maier-Flaig, Florian; Lemmer, Uli

    2013-01-01

    Single-mode second order distributed feedback (DFB) lasers of riboflavin (vitamin B2) doped gelatine films on nanostructured low refractive index material are demonstrated. Manufacturing is based on a simple UV nanoimprint and spin-coating. Emission wavelengths of 543 nm and 562 nm for two...

  13. Volume production of polarization controlled single-mode VCSELs

    Science.gov (United States)

    Grabherr, Martin; King, Roger; Jäger, Roland; Wiedenmann, Dieter; Gerlach, Philipp; Duckeck, Denise; Wimmer, Christian

    2008-02-01

    Over the past 3 years laser based tracking systems for optical PC mice have outnumbered the traditional VCSEL market datacom by far. Whereas VCSEL for datacom in the 850 nm regime emit in multipe transverse modes, all laser based tracking systems demand for single-mode operation which require advanced manufacturing technology. Next generation tracking systems even require single-polarization characteristics in order to avoid unwanted movement of the pointer due to polarization flips. High volume manufacturing and optimized production methods are crucial for achieving the addressed technical and commercial targets of this consumer market. The resulting ideal laser source which emits single-mode and single-polarization at low cost is also a promising platform for further applications like tuneable diode laser absorption spectroscopy (TDLAS) or miniature atomic clocks when adapted to the according wavelengths.

  14. Single-mode quantum cascade lasers employing a candy-cane shaped monolithic coupled cavity

    Science.gov (United States)

    Liu, Peter Q.; Sladek, Kamil; Wang, Xiaojun; Fan, Jen-Yu; Gmachl, Claire F.

    2011-12-01

    We demonstrate single-mode quantum cascade lasers emitting at ˜4.5 μm by employing a monolithic "candy-cane" shaped coupled-cavity consisting of a straight section connecting at one end to a spiral section. The fabrication process is identical to those for simple Fabry-Perot-type ridge lasers. Continuously tunable single-mode emission across ˜8 cm-1 with side mode suppression ratio up to ˜25 dB and a single-mode operating current range of more than 70% above the threshold current is achieved when the lasers are operated in pulsed-mode from 80 K to 155 K.

  15. On- and off-grid operation of hybrid renewable power plants: When are the economics favorable?

    Science.gov (United States)

    Petrakopoulou, F.; Santana, D.

    2016-12-01

    Hybrid renewable energy conversion systems offer a good alternative to conventional systems in locations where the extension of the electrical grid is difficult or not economical or where the cost of electricity is high. However, stand-alone operation implies net energy output restrictions (limited to exclusively serve the energy demand of a region), capacity oversizing and large storage facilities. In interconnected areas, on the other hand, the operational restrictions of the power stations change significantly and the efficiencies and costs of renewable technologies become more favorable. In this paper, the operation of three main renewable technologies (CSP, PV and wind) is studied assuming both hybrid and individual operation for both autonomous and inter-connected operation. The case study used is a Mediterranean island of ca. 3,000 inhabitants. Each system is optimized to fully cover the energy demand of the community. In addition, in the on-grid operation cases, it is required that the annual energy generated from the renewable sources is net positive (i.e., the island generates at least as much energy as it uses). It is found that when connected to the grid, hybridization of more than one technology is not required to satisfy the energy demand, as expected. Each of the renewable technologies investigated can satisfy the annual energy demand individually, without significant complications. In addition, the cost of electricity generated with the three studied technologies drops significantly for on-grid applications, when compared to off-grid operation. However, when compared to business-as-usual scenarios in both the on- and off-grid cases, both investigated hybrid and single-technology renewable scenarios are found to be economically viable. A sensitivity analysis reveals the limits of the acceptable costs that make the technologies favorable when compared to conventional alternatives.

  16. Preserving the B-Cell Compartment Favors Operational Tolerance in Human Renal Transplantation

    Science.gov (United States)

    Silva, Hernandez M; Takenaka, Maisa C S; Moraes-Vieira, Pedro M M; Monteiro, Sandra M; Hernandez, Maristela O; Chaara, Wahiba; Six, Adrien; Agena, Fabiana; Sesterheim, Patrícia; Barbé-Tuana, Florencia Maria; Saitovitch, David; Lemos, Francine; Kalil, Jorge; Coelho, Verônica

    2012-01-01

    Transplanted individuals in operational tolerance (OT) maintain long-term stable graft function after completely stopping immunosuppression. Understanding the mechanisms involved in OT can provide valuable information about pathways to human transplantation tolerance. Here we report that operationally tolerant individuals display quantitative and functional preservation of the B-cell compartment in renal transplantation. OT exhibited normal numbers of circulating total B cells, naive, memory and regulatory B cells (Bregs) as well as preserved B-cell receptor repertoire, similar to healthy individuals. In addition, OT also displayed conserved capacity to activate the cluster of differentiation 40 (CD40)/signal transducer and activator of transcription 3 (STAT3) signaling pathway in Bregs, in contrast, with chronic rejection. Rather than expansion or higher activation, we show that the preservation of the B-cell compartment favors OT. PMID:22252714

  17. Mid-Infrared Continuously Tunable Single Mode VECSEL

    Science.gov (United States)

    Khiar, A.; Rahim, M.; Felder, F.; Fill, M.; Zogg, H.

    2011-12-01

    Tunable mid-infrared vertical external cavity surface emitting lasers were developed for the wavelength range around 3.8-3.9 μm and 3.2-3.3 μm, respectively. The devices are based on lead salt materials epitaxially grown by MBE on a Si substrate. The active part consists of PbSe QW in a PbSrSe host layer. Both devices are operated around -20 °C and have output power of several 10 mW. By changing the cavity length, a single mode hop free tuning range up to 80 cm-1 is achieved.

  18. 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....

  19. Cross-correlated imaging of single-mode photonic crystal rod fiber with distributed mode filtering

    DEFF Research Database (Denmark)

    Laurila, Marko; Barankov, Roman; Jørgensen, Mette Marie

    2013-01-01

    Photonic crystal bandgap fibers employing distributed mode filtering design provide near diffraction-limited light outputs, a critical property of fiber-based high-power lasers. Microstructure of the fibers is tailored to achieve single-mode operation at specific wavelength by resonant mode...... identify regimes of resonant coupling between higher-order core modes and cladding band. We demonstrate a passive fiber design in which the higher-order modal content inside the single-mode guiding regime is suppressed by at least 20 dB even for significantly misaligned input-coupling configurations....

  20. Transverse single-mode edge-emitting lasers based on coupled waveguides.

    Science.gov (United States)

    Gordeev, Nikita Yu; Payusov, Alexey S; Shernyakov, Yuri M; Mintairov, Sergey A; Kalyuzhnyy, Nikolay A; Kulagina, Marina M; Maximov, Mikhail V

    2015-05-01

    We report on the transverse single-mode emission from InGaAs/GaAs quantum well edge-emitting lasers with broadened waveguide. The lasers are based on coupled large optical cavity (CLOC) structures where high-order vertical modes of the broad active waveguide are suppressed due to their resonant tunneling into a coupled single-mode passive waveguide. The CLOC lasers have shown stable Gaussian-shaped vertical far-field profiles with a reduced divergence of ∼22° FWHM (full width at half-maximum) in CW (continuous-wave) operation.

  1. Cantilever-based sensor with integrated optical read-out using single mode waveguides

    DEFF Research Database (Denmark)

    Nordström, Maria; Zauner, Dan; Calleja, Montserrat

    2007-01-01

    surface. Here, we present a novel integrated optical read-out scheme based on single-mode waveguides that enables the fabrication of a compact system. The complete system is fabricated in the polymer SU-8. This manuscript shows the principle of operation and the design well as the fabrication...

  2. Quasi-single-mode homogeneous 31-core fibre

    DEFF Research Database (Denmark)

    Sasaki, Y.; Saitoh, S.; Amma, Y.

    2015-01-01

    A homogeneous 31-core fibre with a cladding diameter of 230 μm for quasi-single-mode transmission is designed and fabricated. LP01-crosstalk of -38.4 dB/11 km at 1550 nm is achieved by using few-mode trench-assisted cores.......A homogeneous 31-core fibre with a cladding diameter of 230 μm for quasi-single-mode transmission is designed and fabricated. LP01-crosstalk of -38.4 dB/11 km at 1550 nm is achieved by using few-mode trench-assisted cores....

  3. Single-mode fibre coupler as refractometer sensor

    Indian Academy of Sciences (India)

    We report a simple, non-intrusive fibre-optic refractometer sensor for measuring the refractive index of liquid and optically transparent solid medium. Sensing principle of the proposed sensor is based on monitoring the back-reflected light signal through the second input port of a 2 × 1 single-mode fibre coupler when light ...

  4. Single-mode multicore fiber for dense space division multiplexing

    DEFF Research Database (Denmark)

    Sasaki, Yusuke; Amma, Yoshimichi; Takenaga, Katsuhiro

    2016-01-01

    Single-mode multicore fiber (SM-MCF) is attractive for high-capacity transmission. Our fabricated SM-MCFs achieve high core count and low crosstalk with a cladding diameter of 230 µm. Characteristics of fan-in/fan-out for the SM-MCFs are also investigated....

  5. A finite element characterization of a commercial endlessly single-mode photonic crystal fiber: is it really single mode?

    NARCIS (Netherlands)

    Uranus, H.P.; Hoekstra, Hugo; van Groesen, Embrecht W.C.

    2007-01-01

    One of interesting properties of photonic crystal fibers (PCFs) is their possibility to be single-moded over a wide wavelength range, down to UV, while still having a reasonably large modal profile. Such properties are attractive for applications like optical sensing, interferometry, and transport

  6. Watt-level widely tunable single-mode emission by injection-locking of a multimode Fabry-Perot quantum cascade laser

    Science.gov (United States)

    Chevalier, Paul; Piccardo, Marco; Anand, Sajant; Mejia, Enrique A.; Wang, Yongrui; Mansuripur, Tobias S.; Xie, Feng; Lascola, Kevin; Belyanin, Alexey; Capasso, Federico

    2018-02-01

    Free-running Fabry-Perot lasers normally operate in a single-mode regime until the pumping current is increased beyond the single-mode instability threshold, above which they evolve into a multimode state. As a result of this instability, the single-mode operation of these lasers is typically constrained to few percents of their output power range, this being an undesired limitation in spectroscopy applications. In order to expand the span of single-mode operation, we use an optical injection seed generated by an external-cavity single-mode laser source to force the Fabry-Perot quantum cascade laser into a single-mode state in the high current range, where it would otherwise operate in a multimode regime. Utilizing this approach, we achieve single-mode emission at room temperature with a tuning range of 36 cm-1 and stable continuous-wave output power exceeding 1 W at 4.5 μm. Far-field measurements show that a single transverse mode is emitted up to the highest optical power, indicating that the beam properties of the seeded Fabry-Perot laser remain unchanged as compared to free-running operation.

  7. Characteristics of SBS dynamics in single-mode optical fibres

    Science.gov (United States)

    Gordeev, A. A.; Efimkov, V. F.; Zubarev, I. G.; Mikhailov, S. I.; Sobolev, V. B.

    2016-03-01

    The characteristics of the gain of Stokes pulses in single-mode optical fibres by stimulated Brillouin scattering (SBS) of monochromatic and nonmonochromatic pump signals have been investigated by numerical simulation using a spectral approach. Conditions under which 'slow light' (caused by a group delay) can be implemented are found (it is reasonable to apply this term to a process in which a pulse is delayed with conservation of its shape). The plane-wave interaction model is shown to describe adequately the dynamics of this process in single-mode fibres. A number of gain modes are investigated for Stokes pulses with different time structures upon monochromatic and nonmonochromatic excitation. A new data transfer technique is proposed, which is based on the conversion of stepwise phase modulation of the input Stokes signal into amplitude modulation of the output signal.

  8. Characteristics of SBS dynamics in single-mode optical fibres

    Energy Technology Data Exchange (ETDEWEB)

    Gordeev, A A; Efimkov, V F; Zubarev, I G; Mikhailov, S I; Sobolev, V B [P N Lebedev Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation)

    2016-03-31

    The characteristics of the gain of Stokes pulses in single-mode optical fibres by stimulated Brillouin scattering (SBS) of monochromatic and nonmonochromatic pump signals have been investigated by numerical simulation using a spectral approach. Conditions under which 'slow light' (caused by a group delay) can be implemented are found (it is reasonable to apply this term to a process in which a pulse is delayed with conservation of its shape). The plane-wave interaction model is shown to describe adequately the dynamics of this process in single-mode fibres. A number of gain modes are investigated for Stokes pulses with different time structures upon monochromatic and nonmonochromatic excitation. A new data transfer technique is proposed, which is based on the conversion of stepwise phase modulation of the input Stokes signal into amplitude modulation of the output signal. (nonlinear optical phenomena)

  9. Coherence properties of a single-mode polariton laser

    Science.gov (United States)

    Kim, Seonghoon; Zhang, Bo; Wang, Zhaorong; Deng, Hui; Fischer, Julian; Brodbeck, Sebastian; Kamp, Martin; Schneider, Christian; Hofling, Sven; Univ of Michigan-Ann Arbor Collaboration; Univ of Wuerzberg Collaboration

    2016-05-01

    Exciton-polariton condensation is a promising low threshold coherent light source, namely a polariton laser. However, first- and second-order coherences of a polariton laser has been poor and not well understood in two dimensional microcavity systems. Here, we show experimentally that full second-order coherence is established in a single-mode polariton laser and maintained far above the lasing threshold. The coherence time of first-order coherence functions increases initially and then reduces as the number of polaritons in a ground state increases due to the polariton-polariton interaction. Moreover, a transition in spectral lineshape from Lorentzian to Gaussian was observed as the occupation number increases as a result of the large interaction energy. These results are in very good agreement with a single-mode atom laser theory. The single-mode polariton laser was realized by designing a subwavelength grating (SWG) mirror which provides strong lateral confinement for discrete polariton states and polarization-selective reflectance for lifted spin-degeneracy. The results would be important for making fully coherent polariton lasers, as well as nonlinear polariton devices.

  10. Single mode step-index polymer optical fiber for humidity insensitive high temperature fiber Bragg grating sensors

    OpenAIRE

    Woyessa, Getinet; Fasano, Andrea; Stefani, Alessio; Markos, Christos; Nielsen, Kristian; Rasmussen, Henrik K.; Bang, Ole

    2016-01-01

    We have fabricated the first single-mode step-index and humidity insensitive polymer optical fiber operating in the 850 nm wavelength ranges. The step-index preform is fabricated using injection molding, which is an efficient method for cost effective, flexible and fast preparation of the fiber preform. The fabricated single-mode step-index (SI) polymer optical fiber (POF) has a 4.8µm core made from TOPAS grade 5013S-04 with a glass transition temperature of 134°C and a 150 µm cladding made f...

  11. Single-mode theory of diffusive layers in thermohaline convection

    Science.gov (United States)

    Gough, D. O.; Toomre, J.

    1982-01-01

    A two-layer configuration of thermohaline convection is studied, with the principal aim of explaining the observed independence of the buoyancy-flux ratio on the stability parameter when the latter is large. Temperature is destabilizing and salinity is stabilizing, so diffusive interfaces separate the convecting layers. The convection is treated in the single-mode approximation, with a prescribed horizontal planform and wavenumber. Surveys of numerical solutions are presented for a selection of Rayleigh numbers R, stability parameters lambda and horizontal wavenumbers. The solutions yield a buoyancy flux ratio chi that is insensitive to lambda, in accord with laboratory experiments. However chi increases with increasing R, in contradiction to laboratory observations.

  12. Single-mode optical-waveguide fiber coupler.

    Science.gov (United States)

    Noda, J; Mikami, O; Minakata, M; Fukuma, M

    1978-07-01

    A single-mode fiber coupler to the Ti diffused LiNbO(3) strip waveguide has been devised. The influences of three axial displacements and two angular misalignments on the coupling efficiency have been investigated at 6328-A wavelength. The coupler has a special feature wherein coupling degradation caused by fiber displacement after connection can be recovered to the initial state. The total optical insertion loss is 3 dB after fixing the fiber to the LiNbO(3) strip waveguide, which is 4 microm wide and 8 mm long.

  13. Single mode dye-doped polymer photonic crystal lasers

    DEFF Research Database (Denmark)

    Christiansen, Mads Brøkner; Buss, Thomas; Smith, Cameron

    2010-01-01

    Dye-doped polymer photonic crystal (PhC) lasers fabricated by combined nanoimprint and photolithography are studied for their reproducibility and stability characteristics. We introduce a phase shift in the PhC lattice that substantially improves the yield of single wavelength emission. Single mode...... emission and reproducibility of laser characteristics are important if the lasers are to be mass produced in, e. g., optofluidic sensor chips. The fabrication yield is above 85% with highly reproducible wavelengths (within 0.5%), and the temperature dependence on the wavelength is found to be -0.045 or -0...

  14. Low-NA single-mode LMA photonic crystal fiber amplifier

    DEFF Research Database (Denmark)

    Alkeskjold, Thomas Tanggaard; Laurila, Marko; Scolari, Lara

    2011-01-01

    Enabling Single-Mode (SM) operation in Large-Mode-Area (LMA) fiber amplifiers and lasers is critical, since a SM output ensures high beam quality and excellent pointing stability. In this paper, we demonstrate and test a new design approach for achieving ultra-low NA SM rod fibers by using...... a spatially Distributed Mode Filter (DMF). This approach achieves SM performance in a short and straight rod fiber and allows preform tolerances to be compensated during draw. A low-NA SM rod fiber amplifier having a mode field diameter of ~60μm at 1064nm and a pump absorption of 27dB/m at 976nm...

  15. Single-mode ytterbium-doped large-mode-area photonic bandgap rod fiber amplifier

    DEFF Research Database (Denmark)

    Alkeskjold, Thomas Tanggaard; Scolari, Lara; Broeng, Jes

    2011-01-01

    Enabling Single-Mode (SM) operation in Large-Mode-Area (LMA) fiber amplifiers and lasers is critical, since a SM output ensures high beam quality and excellent pointing stability. In this paper, we demonstrate and test a new design approach for achieving SM LMA rod fibers by using a photonic...... bandgap structure. The structure allows resonant coupling of higher-order modes from the core and acts as a spatially Distributed Mode Filter (DMF). With this approach, we demonstrate passive SM performance in an only ~50cm long and straight ytterbium-doped rod fiber. The amplifier has a mode field...

  16. A novel hybrid III–V/silicon deformed micro-disk single-mode laser

    International Nuclear Information System (INIS)

    Feng Peng; Zhang Yejin; Liu Lei; Zhang Siriguleng; Wang Hailing; Zheng Wanhua; Wang Yufei

    2015-01-01

    A novel hybrid III–V/silicon deformed micro-disk single-mode laser connecting to a Si output waveguide is designed, and fabricated through BCB bonding technology and standard i-line photolithography. Compared to a traditional circular micro-disk in multi-longitudinal-mode operation, unidirectional emission and single longitudinal-mode output from a Si waveguide are realized. In the experiments, an output power of 0.31 mW and a side-mode suppression ratio of 27 dB in the continuous-wave regime are obtained. (semiconductor devices)

  17. GaSb-based single-mode distributed feedback lasers for sensing (Conference Presentation)

    Science.gov (United States)

    Gupta, James A.; Bezinger, Andrew; Lapointe, Jean; Poitras, Daniel; Aers, Geof C.

    2017-02-01

    GaSb-based tunable single-mode diode lasers can enable rapid, highly-selective and highly-sensitive absorption spectroscopy systems for gas sensing. In this work, single-mode distributed feedback (DFB) laser diodes were developed for the detection of various trace gases in the 2-3.3um range, including CO2, CO, HF, H2S, H2O and CH4. The lasers were fabricated using an index-coupled grating process without epitaxial regrowth, making the process significantly less expensive than conventional DFB fabrication. The devices are based on InGaAsSb/AlGaAsSb separate confinement heterostructures grown on GaSb by molecular beam epitaxy. DFB lasers were produced using a two step etch process. Narrow ridge waveguides were first defined by optical lithography and etched into the semiconductor. Lateral gratings were then defined on both sides of the ridge using electron-beam lithography and etched to produce the index-grating. Effective index modeling was used to optimize the ridge width, etch depths and the grating pitch to ensure single-lateral-mode operation and adequate coupling strength. The effective index method was further used to simulate the DFB laser emission spectrum, based on a transfer matrix model for light transmission through the periodic structure. The fabricated lasers exhibit single-mode operation which is tunable through the absorption features of the various target gases by adjustment of the drive current. In addition to the established open-path sensing applications, these devices have great potential for optoelectronic integrated gas sensors, making use of integrated photodetectors and possibly on-chip Si photonics waveguide structures.

  18. Single-Mode WGM Resonators Fabricated by Diamond Turning

    Science.gov (United States)

    Grudinin, Ivan; Maleki, Lute; Savchenkov, Anatoliy; Matsko, Andrewy; Strekalov, Dmitry; Iltchenko, Vladimir

    2008-01-01

    A diamond turning process has made possible a significant advance in the art of whispering-gallery-mode (WGM) optical resonators. By use of this process, it is possible to fashion crystalline materials into WGM resonators that have ultrahigh resonance quality factors (high Q values), are compact (ranging in size from millimeters down to tens of microns), and support single electromagnetic modes. This development combines and extends the developments reported in "Few- Mode Whispering-Gallery-Mode Resonators" (NPO-41256), NASA Tech Briefs, Vol. 30, No. 1 (January 2006), page 16a and "Fabrication of Submillimeter Axisymmetric Optical Components" (NPO-42056), NASA Tech Briefs, Vol. 31, No. 5 (May 2007), page 10a. To recapitulate from the first cited prior article: A WGM resonator of this special type consists of a rod, made of a suitable transparent material, from which protrudes a thin circumferential belt of the same material. The belt is integral with the rest of the rod and acts as a circumferential waveguide. If the depth and width of the belt are made appropriately small, then the belt acts as though it were the core of a single-mode optical fiber: the belt and the rod material adjacent to it support a single, circumferentially propagating mode or family of modes. To recapitulate from the second cited prior article: A major step in the fabrication of a WGM resonator of this special type is diamond turning or computer numerically controlled machining of a rod of a suitable transparent crystalline material on an ultrahigh-precision lathe. During the rotation of a spindle in which the rod is mounted, a diamond tool is used to cut the rod. A computer program is used to control stepping motors that move the diamond tool, thereby controlling the shape cut by the tool. Because the shape can be controlled via software, it is possible to choose a shape designed to optimize a resonator spectrum, including, if desired, to limit the resonator to supporting a single mode

  19. Single-Mode, Distributed Feedback Interband Cascade Lasers

    Science.gov (United States)

    Frez, Clifford F. (Inventor); Borgentun, Carl E. (Inventor); Briggs, Ryan M. (Inventor); Bagheri, Mahmood (Inventor); Forouhar, Siamak (Inventor)

    2016-01-01

    Single-mode, distributed feedback interband cascade lasers (ICLs) using distributed-feedback gratings (e.g., lateral Bragg gratings) and methods of fabricating such ICLs are provided. The ICLs incorporate distributed-feedback gratings that are formed above the laser active region and adjacent the ridge waveguide (RWG) of the ICL. The ICLs may incorporate a double-ridge system comprising an optical confinement structure (e.g., a RWG) disposed above the laser active region that comprises the first ridge of the double ridge system, a DFB grating (e.g., lateral Bragg grating) disposed above the laser active region and adjacent the optical confinement structure, and an electric confinement structure that passes at least partially through the laser active region and that defines the boundary of the second ridge comprises and the termination of the DFB grating.

  20. Picosecond chirped pulse compression in single-mode fibers

    International Nuclear Information System (INIS)

    Wenhua Cao; Youwei Zhang

    1995-01-01

    In this paper, the nonlinear propagation of picosecond chirped pulses in single mode fibers has been investigated both analytically and numerically. Results show that downchirped pulses can be compressed owing to normal group-velocity dispersion. The compression ratio depends both on the initial peak power and on the initial frequency chirp of the input pulse. While the compression ratio depends both on the initial peak power and on the initial frequency chirp of the input pulse. While the compression ratio increases with the negative frequency chirp, it decreases with the initial peak power of the input pulse. This means that the self-phase modulation induced nonlinear frequency chirp which is linear and positive (up-chirp) over a large central region of the pulse and tends to cancel the initial negative chirp of the pulse. It is also shown that, as the negative chirped pulse compresses temporally, it synchronously experiences a spectral narrowing

  1. Mid-infrared performance of single mode chalcogenide fibers

    Science.gov (United States)

    Cook, Justin; Sincore, Alex; Tan, Felix; El Halawany, Ahmed; Riggins, Anthony; Shah, Lawrence; Abouraddy, Ayman F.; Richardson, Martin C.; Schepler, Kenneth L.

    2018-02-01

    Due to the intrinsic absorption edge in silica near 2.4 μm, more exotic materials are required to transmit laser power in the IR such as fluoride or chalcogenide glasses (ChGs). In particular, ChG fibers offer broad IR transmission with low losses fibers at four different infrared wavelengths: 2053 nm, 2520 nm and 4550 nm. Polymer clad ChG fibers were drawn with 12.3 μm and 25 μm core diameters. Testing at 2053 nm was accomplished using a > 15 W, CW Tm:fiber laser. Power handling up to 10.2 W with single mode beam quality has been demonstrated, limited only by the available Tm:fiber output power. Anti-reflective coatings were successfully deposited on the ChG fiber facets, allowing up to 90.6% transmission with 12.2 MW/cm2 intensity on the facet. Single mode guidance at 4550 nm was also demonstrated using a quantum cascade laser (QCL). A custom optical system was constructed to efficiently couple the 0.8 NA QCL radiation into the 0.2 NA ChG fiber, allowing for a maximum of 78% overlap between the QCL radiation and fundamental mode of the fiber. With an AR-coated, 25 μm core diameter fiber, >50 mW transmission was demonstrated with > 87% transmission. Finally, we present results on fiber coupling from a free space Cr:ZnSe resonator at 2520 nm.

  2. Strain sensor based on gourd-shaped single-mode-multimode-single-mode hybrid optical fibre structure.

    Science.gov (United States)

    Tian, Ke; Farrell, Gerald; Wang, Xianfan; Yang, Wenlei; Xin, Yifan; Liang, Haidong; Lewis, Elfed; Wang, Pengfei

    2017-08-07

    A fibre-optic strain sensor based on a gourd-shaped joint multimode fibre (MMF) sandwiched between two single-mode fibres (SMFs) is described both theoretically and experimentally. The cladding layers of the two MMFs are reshaped to form a hemisphere using an electrical arc method and spliced together, yielding the required gourd shape. The gourd-shaped section forms a Fabry-Perot cavity between the ends of two adjacent but non-contacting multimode fibres' core. The effectiveness of the multimode interference based on the Fabry-Perot interferometer (FPI) formed within the multimode inter-fibre section is greatly improved resulting in an experimentally determined strain sensitivity of -2.60 pm/με over the range 0-1000 με. The sensing characteristics for temperature and humidity of this optical fibre strain sensor are also investigated.

  3. Report on first masing and single mode locking in a prebunched beam FEM oscillator

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, M.; Eichenbaum, A.; Kleinman, H. [Tel-Aviv Univ., Ramat-Aviv (Israel)] [and others

    1995-12-31

    Radiation characteristics of a table-top free electron maser (FEM) are described in this paper. The FEM employs a prebunched electron beam and is operated as an oscillator in the low-gain collective (Raman) regime. Using electron beam prebunching single mode locking at any one of the possible oscillation modes was obtained. The electron beam is prebunched by a microwave tube section before it is injected into the wiggler. By tuning the electron beam bunching frequency, the FEM oscillation frequency can be locked to any eigen frequency of the resonant waveguide cavity which is within the frequency band of net gain of the FEM. The oscillation build up process is sped up, when the FEM operates with a prebunched electron beam, and the build-up time of radiation is shortened significantly. First measurements of masing with and without prebunching and characterization of the emitted radiation are reported.

  4. Single mode step-index polymer optical fiber for humidity insensitive high temperature fiber Bragg grating sensors

    DEFF Research Database (Denmark)

    Woyessa, Getinet; Fasano, Andrea; Stefani, Alessio

    2016-01-01

    We have fabricated the first single-mode step-index and humidity insensitive polymer optical fiber operating in the 850 nm wavelength ranges. The step-index preform is fabricated using injection molding, which is an efficient method for cost effective, flexible and fast preparation of the fiber...... preform. The fabricated single-mode step-index (SI) polymer optical fiber (POF) has a 4.8µm core made from TOPAS grade 5013S-04 with a glass transition temperature of 134°C and a 150 µm cladding made from ZEONEX grade 480R with a glass transition temperature of 138°C. The key advantages of the proposed...... SIPOF are low water absorption, high operating temperature and chemical inertness to acids and bases and many polar solvents as compared to the conventional poly-methyl-methacrylate (PMMA) and polystyrene based POFs. In addition, the fiber Bragg grating writing time is short compared to microstructured...

  5. Single mode step-index polymer optical fiber for humidity insensitive high temperature fiber Bragg grating sensors.

    Science.gov (United States)

    Woyessa, Getinet; Fasano, Andrea; Stefani, Alessio; Markos, Christos; Nielsen, Kristian; Rasmussen, Henrik K; Bang, Ole

    2016-01-25

    We have fabricated the first single-mode step-index and humidity insensitive polymer optical fiber operating in the 850 nm wavelength ranges. The step-index preform is fabricated using injection molding, which is an efficient method for cost effective, flexible and fast preparation of the fiber preform. The fabricated single-mode step-index (SI) polymer optical fiber (POF) has a 4.8µm core made from TOPAS grade 5013S-04 with a glass transition temperature of 134°C and a 150 µm cladding made from ZEONEX grade 480R with a glass transition temperature of 138°C. The key advantages of the proposed SIPOF are low water absorption, high operating temperature and chemical inertness to acids and bases and many polar solvents as compared to the conventional poly-methyl-methacrylate (PMMA) and polystyrene based POFs. In addition, the fiber Bragg grating writing time is short compared to microstructured POFs.

  6. Pump combiner for air-clad fiber with PM single-mode signal feed-through

    DEFF Research Database (Denmark)

    Noordegraaf, Danny; Nielsen, Martin D.; Skovgaard, Peter M.W.

    2009-01-01

    A pump combiner with single-mode PM signal feed-through designed for an air-clad photonic crystal fiber is demonstrated. Signal coupling is realized by a novel taper element allowing single-mode guidance at a taper ratio of 3.7.......A pump combiner with single-mode PM signal feed-through designed for an air-clad photonic crystal fiber is demonstrated. Signal coupling is realized by a novel taper element allowing single-mode guidance at a taper ratio of 3.7....

  7. 3-4.5 μm continuously tunable single mode VECSEL

    Science.gov (United States)

    Fill, M.; Felder, F.; Rahim, M.; Khiar, A.; Zogg, H.

    2012-11-01

    We present continuously tunable Vertical External Cavity Surface Emitting Lasers (VECSEL) in the mid-infrared. The structure based on IV-VI semiconductors is epitaxially grown on a Si-substrates. The VECSEL emit one single mode, which is mode hop-free tunable over 50-100 nm around the center wavelength. In this work, two different devices are presented, emitting at 3.4 μm and 3.9 μm, respectively. The lasers operate near room temperature with thermoelectric stabilization. They are optically pumped, yielding an output power >10 mWp. The axial symmetric emission beam has a half divergence angle of <3.3∘.

  8. Choosing a Better Delay Line Medium between Single-Mode and Multi-Mode Optical Fibers: the Effect of Bending

    Directory of Open Access Journals (Sweden)

    Auwal Mustapha Imam

    2017-12-01

    Full Text Available Optical fiber cables are materials whose core is made of silica and other materials such as chalcogenide glasses; they transmit a digital signal via light pulses through an extremely thin strand of glass. The light propagates and is being guided by the core which is surrounded by the cladding. Light travels in the optical fiber in the form of total internal reflection in the core of the fibers. The flexibility, low tensile strength, low signal loss, high bandwidth and other characteristics of optical fibers favors it for use as a delay medium in many applications. Another favorable characteristic of optical fiber delay lines is are their relative insensitivities to environmental effects and electromagnetic interferences. The immunity of optical fibers to interferences and their less weight added advantages to it for use as delay medium. Single-mode and multi-mode are the two most popular types of optical fibers. Single-mode fibers have good propagation and delay properties with a minimal loss that allows the signal to propagate in a large distance with insignificant distortion or attenuation. The percentage of power transmission of single-mode fibers is found to be higher than that of the multi-mode fibers. It is, therefore, a preferred type for use as a delay line. In this paper, relative studies of the two optical fibers modes, and the results of power input/output measurement of the two modes are presented with a view to coming up with a better type for use as a delay medium.

  9. Investigation of single-mode vertical-cavity surface-emitting lasers with graphene-bubble dielectric DBR

    Science.gov (United States)

    Guan, Baolu; Li, Pengtao; Arafin, Shamsul; Alaskar, Yazeed; Wang, Kang L.

    2018-02-01

    An inter-cavty contact single mode 850 nm VCSEL was fabricated with a graphene assisted self-assembly curved dielectric bubble Bragg mirror for the first time. Taking the advantage of graphene's uniform low surface energy, the low cost dielectric bubble DBR (Si3N4/SiO2) was deposited on top of the graphene/half-VCSEL structure via van der Waals Force (vdWF) without using any additional spacing elements and sacrificial layer release-etch process. The continuous-wave operating VCSELs with an aperture diameter of 7 μm exhibit single-mode output power of more than 1 mW with a slope efficiency of 0.2 W/A. The sidemode suppression ratios are >40 dB. This novel modification into the lasers can also be applied to a variety of other optoelectronic devices, such as resonance photodetecter and super narrow linewidth VCSEL.

  10. Modes of an endlessly single-mode photonic crystal fiber: a finite element investigation

    NARCIS (Netherlands)

    Uranus, H.P.; Hoekstra, Hugo; van Groesen, Embrecht W.C.

    2004-01-01

    Using a finite-element mode solver, the modes of a commercial endlessly single-mode photonic crystal fiber (ESM-PCF) were investigated. Based on the loss discrimination between the dominant and the nearest higher order mode, we set-up a criterion for the single-modeness. Using that measure, we

  11. Investigation of the state of polarization of light in a single-mode fiber waveguide

    Science.gov (United States)

    Kozel, S. M.; Kreopalov, V. I.; Listvin, V. N.; Glavatskikh, N. A.

    1983-01-01

    An analysis is made of the polarization anisotropy of a single-mode fiber with a twisted elliptic core. The Jones matrix is obtained and the complex function of the state of polarization of light in a fiber is investigated. The results are reported of measurements of the linear and circular birefringence of a borosilicate single-mode glass fiber.

  12. Single-Mode Deceleration Stage Rayleigh-Taylor Instability Growth in Cylindrical Implosions

    Science.gov (United States)

    Sauppe, J. P.; Palaniyappan, S.; Bradley, P. A.; Batha, S. H.; Loomis, E. N.; Kline, J. L.; Srinivasan, B.; Bose, A.; Malka, E.; Shvarts, D.

    2017-10-01

    We present design calculations demonstrating the feasibility of measuring single-mode deceleration stage Rayleigh-Taylor instability (RTI) growth at a factor of four convergence. RTI growth rates are modified as a result of convergence [Bell LA-1321, 1951], and cylindrical targets are considered here, as they allow direct diagnostic access along the interface. The 2D computations, performed with the radiation-hydrodynamics code xRAGE [Gittings et al., CSD 2008] utilizing a new laser ray-tracing package, predict growth factors of 6 to 10 for mode 10 and 4 to 6 for mode 4, both of high interest in evaluating inertial confinement fusion capsule degradation mechanisms [Bose et al., this conference]. These results compare favorably to a linear theory [Epstein, PoP 2004] and to a buoyancy-drag model [Srebro et al., LPB 2003], which accounts for the linear and non-linear stages. Synthetic radiographs, produced by combining 2D computations of axial and transverse cross-sections, indicate this growth will be observable, and these will be compared to experimental data obtained at the OMEGA laser facility. Work performed by Los Alamos National Laboratory under contract DE-AC52-06NA25396 for the National Nuclear Security Administration of the U.S. Department of Energy. (LA-UR-17-25608).

  13. Over 19 W Single-Mode 1545 nm Er,Yb Codoped All-Fiber Laser

    Directory of Open Access Journals (Sweden)

    Jiadong Wu

    2017-01-01

    Full Text Available We report a high-power cladding-pumped Er,Yb codoped all-fiber laser with truly single transverse mode output. The fiber laser is designed to operate at 1545 nm by the use of a pair of fiber Bragg gratings (FBGs to lock and narrow the output spectrum, which can be very useful in generating the eye-safe ~1650 nm laser emission through the Stimulated Raman Scattering (SRS in silica fibers that is of interest in many applications. Two pieces of standard single-mode fibers are inserted into the laser cavity and output port to guarantee the truly single-mode output as well as good compatibility with other standard fiber components. We have obtained a maximum output power of 19.2 W at 1544.68 nm with a FWHM spectral width of 0.08 nm, corresponding to an average overall slope efficiency of 31.9% with respect to the launched pump power. This is, to the best of our knowledge, the highest output power reported from simple all-fiber single-mode Er,Yb codoped laser oscillator architecture.

  14. Single mode wavelength control of modulated AlGaAs lasers with external and internal etalon feedback

    Science.gov (United States)

    Maynard, William L.

    1989-01-01

    Single mode lasing without mode hops has been obtained for VSIS and CSP laser diodes with an external etalon attached to the laser's front facet for up to an 8 C range CW and a 4 C range pulsed, with .07 nm/C tuning. Tests of thin tapered-thickness (TTT) laser diodes show CW and pulsed single mode lasing over 10 C and 2 C ranges, respectively, with .08 nm/C tuning. An analysis of the TTT structure reveals the equivalent of an internal etalon. The time-resolved pulsed behavior for both types of lasers show single mode lasing within the proper temperature ranges with minor modes present only early in the optical pulse, if at all. The external etalon produces noticeable interference fringes in the farfield pattern, while those of the TTT lasers are smooth. Ongoing CW lifetest results indicate stability to within one longitudinal mode after a few hundred hours of operation, along with at least several thousand hours lifetime.

  15. Tripartite entanglement of bosonic systems in a noninertial frame beyond the single- mode approximation

    Directory of Open Access Journals (Sweden)

    M Soltani

    2015-12-01

    Full Text Available In this work, we generalize the entanglement of three-qbit Bosonic systems beyond the single-mode approximation when one of the observers is accelerated. For this purpose, we review the effects of acceleration on field modes and quantum states. The single-mode approximation and beyond the single-mode approximation methods are introduced. After this brief introduction, the main problem of this paper, tripartite entanglement of bosonic systems in a noninertial frame beyond the single- mode approximation is investigated. The tripartite entangled states have different classes with GHZ and W states being most important. Here, we choose &pi-tangle as a measure of tripartite entanglement. If the three parties share GHZ state, the corresponding &pi-tangle will increase by increasing acceleration for some Unruh modes. This phenomenon, increasing entanglement, has never been observed in the single-mode approximation for bosonic case. Moreover, the &pi-tangle dose not exhibit a monotonic behavior with increasing acceleration. In the infinite acceleration limit, the &pi-tangle goes to different nonzero values for distinct Unruh modes. Unlike GHZ state, the entanglement of the W state shows only monotonically increasing and decreasing behaviors with increasing acceleration. Also, the entanglement for all possible choices of Unruh modes approaches only 0.176 in the high acceleration limit. Therefore, according to the quantum entanglement, there is no distinction between the single-mode approximation and beyond the single-mode approximation methods in this limit.

  16. Sensors Based on Thin-Film Coated Cladding Removed Multimode Optical Fiber and Single-Mode Multimode Single-Mode Fiber: A Comparative Study

    Directory of Open Access Journals (Sweden)

    Ignacio Del Villar

    2015-01-01

    Full Text Available Two simple optical fibre structures that do not require the inscription of a grating, a cladding removed multimode optical fibre (CRMOF and a single-mode multimode single-mode structure (SMS, are compared in terms of their adequateness for sensing once they are coated with thin-films. The thin-film deposited (TiO2/PSS permits increasing the sensitivity to surrounding medium refractive index. The results obtained can be extrapolated to other fields such as biological or chemical sensing just by replacing the thin-film by a specific material.

  17. Amplitude Noise Suppression and Orthogonal Multiplexing Using Injection-Locked Single-Mode VCSEL

    DEFF Research Database (Denmark)

    Lyubopytov, Vladimir; von Lerber, Tuomo; Lassas, Matti

    2017-01-01

    We experimentally demonstrate BER reduction and orthogonal modulation using an injection locked single-mode VCSEL. It allows us suppressing an amplitude noise of optical signal and/or double the capacity of an information channel....

  18. Refractive index sensor based on an abrupt taper Michelson interferometer in a single-mode fiber.

    Science.gov (United States)

    Tian, Zhaobing; Yam, Scott S-H; Loock, Hans-Peter

    2008-05-15

    A simple refractive index sensor based on a Michelson interferometer in a single-mode fiber is constructed and demonstrated. The sensor consists of a single symmetrically abrupt taper region in a short piece of single-mode fiber that is terminated by approximately 500 nm thick gold coating. The sensitivity of the new sensor is similar to that of a long-period-grating-type sensor, and its ease of fabrication offers a low-cost alternative to current sensing applications.

  19. Highly efficient high power single-mode fiber amplifier utilizing the distributed mode filtering bandgap rod fiber

    DEFF Research Database (Denmark)

    Laurila, Marko; Alkeskjold, Thomas T.; Jørgensen, Mette Marie

    2012-01-01

    We report on an ytterbium doped single mode distributed mode filtering rod fiber in an amplifier configuration delivering high average output power, up to 292 watts, using a mode-locked 30ps source at 1032nm with good power conversion efficiency. We study the modal stability of the output beam...... at high average output power levels and demonstrate a 44% power improvement before the threshold-like onset of mode instabilities by operating the rod fiber in a leaky waveguide regime. We investigate the guiding dynamics of the rod fiber and explain the improved performance by thermally induced...

  20. Toward single-mode UV to near-IR guidance using hollow-core anti-resonant silica fiber

    DEFF Research Database (Denmark)

    Habib, Md Selim; Antonio-Lopez, Jose Enrique; Van Newkirk, Amy

    2017-01-01

    Hollow-core anti-resonant (HC-AR) fibers with a “negative-curvature” of the core-cladding boundary have been extensively studied over the past few years owing to their low loss and wide transmission bandwidths. The key unique feature of the HC-AR fiber is that the coupling between the core and cl...... a silica HC-AR fiber having a single ring of 7 non-touching capillaries, designed to have effectively single-mode operation and low loss from UV to near-IR....

  1. Efficient injection from large telescopes into single-mode fibres: Enabling the era of ultra-precision astronomy

    Science.gov (United States)

    Jovanovic, N.; Schwab, C.; Guyon, O.; Lozi, J.; Cvetojevic, N.; Martinache, F.; Leon-Saval, S.; Norris, B.; Gross, S.; Doughty, D.; Currie, T.; Takato, N.

    2017-08-01

    Photonic technologies offer numerous advantages for astronomical instruments such as spectrographs and interferometers owing to their small footprints and diverse range of functionalities. Operating at the diffraction-limit, it is notoriously difficult to efficiently couple such devices directly with large telescopes. We demonstrate that with careful control of both the non-ideal pupil geometry of a telescope and residual wavefront errors, efficient coupling with single-mode devices can indeed be realised. A fibre injection was built within the Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) instrument. Light was coupled into a single-mode fibre operating in the near-IR (J - H bands) which was downstream of the extreme adaptive optics system and the pupil apodising optics. A coupling efficiency of 86% of the theoretical maximum limit was achieved at 1550 nm for a diffraction-limited beam in the laboratory, and was linearly correlated with Strehl ratio. The coupling efficiency was constant to within 40% for 84% of the time and >50% for 41% of the time. The laboratory results allow us to forecast that extreme adaptive optics levels of correction (Strehl ratio >90% in H-band) would allow coupling of >67% (of the order of coupling to multimode fibres currently) while standard levels of wavefront correction (Strehl ratio >20% in H-band) would allow coupling of >18%. For Strehl ratios <20%, few-port photonic lanterns become a superior choice but the signal-to-noise, and pixel availability must be considered. These results illustrate a clear path to efficient on-sky coupling into a single-mode fibre, which could be used to realise modal-noise-free radial velocity machines, very-long-baseline optical/near-IR interferometers and/or simply exploit photonic technologies in future instrument design.

  2. Development of distributed temperature sensor based on single-mode fiber

    Science.gov (United States)

    Jiang, Mingshun; Wang, Jing; Feng, Dejun; Sui, Qingmei

    2008-12-01

    The distributed optical fiber temperature measurement system (DTS) is a kind of sensing system, which is applied to the real-time measurement of the temperature field in space. It is widely used in monitoring of production process: fire alarm of coal mine and fuel depots, heat detection and temperature monitor of underground cable, seepage and leakage of dam. Through analyzing temperature effect of optical fiber Raman backscattering theoretically, a distributed temperature sensor based on single-mode fiber was designed, which overcame the inadequacies of multimode fiber. The narrow pulse width laser, excellent InGaAS PIN, low noise precision difet operational amplifier and high speed data acquisition card in order to improve the stability of this system were selected. The demodulation method based on ratio of Anti-Stokes and Stokes Raman backscattering intensity was adopted. Both hardware composition and software implementation of the system were introduced in detail. It is proved that its distinguishing ability of temperature and space are 1 m and 2 m, respectively. The system response time is about 180 s, with a sensing range of 5 km and the temperature measurement range 0~100 °C.

  3. Single mode optical fiber vibration sensor: design and development

    Science.gov (United States)

    Alanis-Carranza, L. E.; Alvarez-Chavez, J. A.; Perez-Sanchez, G. G.; Sierra-Calderon, A.; Rodriguez-Novelo, J. C.

    2016-09-01

    This work deals with the design and development of an SMF28-based vibration detector including the fiber segment, the data acquisition via an NI-USB-6212 card, the data processing code in Visual Basic and the signal spectrum obtained via Fourier analysis. The set-up consists of a regulated voltage source at 2.6V, 300mA, which serves as the power source for a 980nm semiconductor laser operating at 150mW which is fiber coupled into a 20m-piece of SMF-28 fiber. Perpendicular to such fiber the perturbations ranged from 1 to 100 kHz, coming from a DC motor at 12 Volts. At the detection stage, a simple analog filter and a commercial photo diode were employed for data acquisition, before a transimpedance amplification stage reconstructed the signal into the National Instruments data acquisition card. At the output, the signals Fourier transformation allows the signal to be displayed in a personal computer. The presentation will include a full electrical and optical characterization of the device and preliminary sensing results, which could be suitable for structural health monitoring applications.

  4. Modeling bidirectionally coupled single-mode semiconductor lasers

    International Nuclear Information System (INIS)

    Mulet, Josep; Masoller, Cristina; Mirasso, Claudio R.

    2002-01-01

    We develop a dynamical model suitable for the description of two mutually coupled semiconductor lasers in a face-to-face configuration. Our study considers the propagation of the electric field along the compound system as well as the evolution of the carrier densities within each semiconductor laser. Mutual injection, passive optical feedback, and multiple reflections are accounted for in this framework, although under weak to moderate coupling conditions. We systematically describe the effect of the coupling strength on the spectrum of monochromatic solutions and on the respective dynamical behavior. By assuming single-longitudinal-mode operation, weak mutual coupling and slowly varying approximation, the dynamical model can be reduced to rate equations describing the mutual injection from one laser to its counterpart and vice versa. A good agreement between the complete and simplified models is found for small coupling. For larger coupling, higher-order terms lead to a smaller threshold reduction, reflected itself in the spectrum of the monochromatic solutions and in the dynamics of the optical power

  5. Comparison of Numerical Modelling of Degradation Mechanisms in Single Mode Optical Fibre Using MATLAB and VPIphotonics

    Directory of Open Access Journals (Sweden)

    Jana Sajgalikova

    2015-01-01

    Full Text Available Mathematical models for description of physical phenomena often use the statistical description of the individual phenomena and solve those using suitable methods. If we want to develop numerical model of optical communication system based on transmission through single mode optical fibres, we need to consider whole series of phenomena that affect various parts of the system. In the single-mode optical fibre we often encounter influence of chromatic dispersion and nonlinear Kerr effects. By observing various different degradation mechanisms, every numerical model should have its own limits, which fulfil more detailed specification. It is inevitable to consider them in evaluation. In this paper, we focus on numerical modelling of degradation mechanisms in single-mode optical fibre. Numerical solution of non-linear Schroedinger equation is performed by finite difference method applied in MATLAB environment and split-step Fourier method, which is implemented by VPIphotonics software.

  6. Single-mode 37-core fiber with a cladding diameter of 248 μm

    DEFF Research Database (Denmark)

    Sasaki, Y.; Takenaga, K.; Aikawa, K.

    2017-01-01

    A heterogeneous single-mode 37-core fiber with a cladding diameter of 248 μm is designed and fabricated. The fiber provides the highest core count and low total-crosstalk less than −20 dB/1000 km in C+L band.......A heterogeneous single-mode 37-core fiber with a cladding diameter of 248 μm is designed and fabricated. The fiber provides the highest core count and low total-crosstalk less than −20 dB/1000 km in C+L band....

  7. Selective mode coupling in microring resonators for single mode semiconductor lasers

    Science.gov (United States)

    Arbabi, Amir

    Single mode semiconductor laser diodes have many applications in optical communications, metrology and sensing. Edge-emitting single mode lasers commonly use distributed feedback structures, or narrowband reflectors such as distributed Bragg reflectors (DBRs) and sampled grating distributed Bragg reflectors (SGDBRs). Compact, narrowband reflectors with high reflectivities are of interest to replace the commonly used DBRs and SGDBRs. This thesis presents our work on the simulation, design, fabrication, and characterization of devices operating based on the coupling of degenerate modes of a microring resonator, and investigation of the possibility of using them for improving the performance of laser diodes. In particular, we demonstrate a new type of compact, narrowband, on-chip reflector realized by selectively coupling degenerate modes of a microring resonator. For the simulation and design of reflective microring resonators, a fast and accurate analysis method is required. Conventional numerical methods for solving Maxwell's equations such as the finite difference time domain and the finite element method (FEM) provide accurate results but are computationally intense and are not suitable for the design of large 3D structures. We formulated a set of coupled mode equations that, combined with 2D FEM simulations, can provide a fast and accurate tool for the modeling and design of reflective microrings. We developed fabrication processing recipes and fabricated passive reflective microrings on silicon substrates with a silicon nitride core and silicon dioxide cladding. Narrowband single wavelength reflectors were realized which are 70 times smaller than a conventional DBR with the same bandwidth. Compared to the conventional DBR, they have faster roll-off, and no side modes. The smaller footprint saves real estate, reduces tuning power and makes these devices attractive as in-line mirrors for low threshold narrow linewidth laser diodes. Self-heating caused by material

  8. Single mode chalcogenide glass fiber as wavefront filter for the DARWIN planet finding misson

    NARCIS (Netherlands)

    Faber, A.J.; Cheng, L.K.; Gielesen, W.L.M.; Boussard-Plédel, C.; Houizot, P.; Danto, S.; Lucas, J.; Pereira Do Carmo, J.

    2017-01-01

    The development of single mode chalcogenide glass fibers as wavefront filter for the DARWIN mission is reported. Melting procedures and different preform techniques for manufacturing core-cladding chalcogenide fibers are described. Bulk glass samples on the basis of Te-As-Se- and high

  9. Efficient multi-mode to single-mode coupling in a photonic lantern

    DEFF Research Database (Denmark)

    Noordegraaf, Danny; Skovgaard, Peter M.; Nielsen, Martin D.

    2009-01-01

    We demonstrate the fabrication of a high performance multi-mode (MM) to single-mode (SM) splitter or “photonic lantern”, first described by Leon-Saval et al. (2005). Our photonic lantern is a solid all-glass version, and we show experimentally that this device can be used to achieve efficient and...

  10. Single-mode hole-assisted fiber as a bending-loss insensitive fiber

    Science.gov (United States)

    Nakajima, Kazuhide; Shimizu, Tomoya; Matsui, Takashi; Fukai, Chisato; Kurashima, Toshio

    2010-12-01

    We investigate the design and characteristics of a single-mode and low bending loss HAF both numerically and experimentally. An air filling fraction S is introduced to enable us to design a HAF with desired characteristics more easily. We show that we can expect to realize a single-mode and low bending loss HAF by considering the S dependence of the bending loss α b and cutoff wavelength λ c as well as their relative index difference Δ dependence. We also show that the mode-field diameter (MFD) and chromatic dispersion characteristics of the single-mode and low bending loss HAF can be tailored by optimizing the distance between the core and the air holes. We also investigate the usefulness of the fabricated HAFs taking the directly modulated transmission and multipath interference (MPI) characteristics into consideration. We show that the designed HAF has sufficient applicability to both analog and digital transmission systems. Our results reveal that the single-mode and low bending loss HAF is beneficial in terms of developing a future fiber to the home (FTTH) network as well as for realizing flexible optical wiring.

  11. Experimental detection of nonclassicality of single-mode fields via intensity moments

    Czech Academy of Sciences Publication Activity Database

    Arkhipov, Ie.I.; Peřina, Jan; Haderka, O.; Michálek, Václav

    2016-01-01

    Roč. 24, č. 26 (2016), s. 29496-29505 ISSN 1094-4087 R&D Projects: GA ČR GAP205/12/0382 Institutional support: RVO:68378271 Keywords : experimental detection of nonclassicality * single-mode fields * intensity moments Subject RIV: BH - Optics , Masers, Lasers Impact factor: 3.307, year: 2016

  12. Lateral emission highly polarized single-mode nanobelt laser (Conference Presentation)

    Science.gov (United States)

    Xu, Pengfei; Liu, Shikai; Li, Ming; Zhou, Zheng; Ren, Zhaohui; Yang, Qing

    2017-02-01

    Nanoscale lasers are the key component in the integrated photonics chips and have attracted much interests. Nanoblets and nanowires lasers, as one of the candidates for the nanoscale lasers, have been developed for one more decades. Many kinds of nanowire lasers with different functionalities, such as wavelength tunable, single mode, polarized emission and so on, have been demonstrated. However, the reported single mode nanowire lasers are mostly realized through microfabrication process, careful manipulation and complicated structures. Here, we present a new type of lateral emission single mode nanobelt lasers with high polarization ratio which are fabricated by the one step traditional VLS (Vapor Liquid Solid) growth. Different from the traditional nanobelt lasers which are based on the FP cavity formed in the longitudinal direction, the emission of this novel nanoblet laser is lateral which is contribute to the special wire-like structures grown on the nanobelt. It shows band edge emission and the wavelength is centered at 712.6 nm with linewidth about 0.18 nm. The threshold reach as low as 15 uJ/cm2 benefit from the unique morphology which provides enhanced confinement factor for optical modes. Meanwhile the laser emission is highly polarized with polarization ration as high as 0.91. This lateral emission single mode nanobelt laser with high polarization ratio, low threshold and simple fabrication technique offers an economic and effective choice to the future optical applications.

  13. Single-mode waveguides with SU-8 polymer core and cladding for MOEMS applications

    DEFF Research Database (Denmark)

    Nordström, Maria; Zauner, Dan; Boisen, Anja

    2007-01-01

    Fabrication and optical characterization of singlemode polymeric embedded waveguides are performed. A specific material combination (SU-8 2005 as core and the modified SU-8 mr-L 6050XP as cladding) is chosen in order to obtain a small refractive index difference for single-mode propagation combin...

  14. 870nm Bragg grating in single mode TOPAS microstructured polymer optical fibre

    DEFF Research Database (Denmark)

    Yuan, Wu; Webb, David J.; Kalli, Kyriacos

    2011-01-01

    We report the fabrication and characterization of a fiber Bragg grating (FBG) with 870 nm resonance wavelength in a single-mode TOPAS microstructured polymer optical fiber (mPOF). The grating has been UV-written with the phase-mask technique using a 325 nm HeCd laser. The static tensile strain...

  15. Analytical Expression for the Electric Field of the Single Mode Laser ...

    African Journals Online (AJOL)

    The simplest model of the laser is that of a single mode system homogenously broadened. The dynamical behavior of this laser is described by three differential equations, called Haken-Lorenz equations[1], similar to the Lorenz model [1] already known to predict deterministic chaos. In previous recent work [5-7] we have ...

  16. Intrinsic pressure response of a single mode cyclo olefin polymer fiber bragg grating

    DEFF Research Database (Denmark)

    Pedersen, Jens Kristian Mølgaard; Woyessa, Getinet; Nielsen, Kristian

    2016-01-01

    The intrinsic pressure response of a Fibre Bragg Grating (FBG) inscribed in a single-mode cyclo olefin polymer (COP) microstructured polymer optical fibre (mPOF) in the range 0-200 bar is investigated for the first time. In order to efficiently suppress the effects from changes in temperature...

  17. Investigation of bending loss in a single-mode optical fibre

    Indian Academy of Sciences (India)

    Abstract. Loss of optical power in a single-mode optical fibre due to bending has been investigated for a wavelength of 1550 nm. In this experiment, the effects of bending radius (4–15 mm, with steps of 1 mm), and wrapping turns (up to 40 turns) on loss have been studied. Twisting the optical fibre and its influence on power ...

  18. Coupled-Mode Theory derivation of the formal equivalence between a three-mode waveguide and a set of three mutually coupled single-mode waveguides

    Directory of Open Access Journals (Sweden)

    Boucher Yann G.

    2017-01-01

    Full Text Available The formal identification between a two-mode waveguide and a system of two mutually coupled single-mode waveguides stems from the symmetries of the evolution operator. When the gap tends to zero, the super-modes of the coupled system merge continuously into the modes of the multimode waveguide. For modelling purposes, it is very tempting to extend the analogy to three-mode waveguides (and beyond. But not without some precautions…

  19. Estimation of Most Favorable Optical Window Position Subject to Achieve Finest Optical Control of Lateral DDR IMPATT Diode Designed to Operate at W-Band

    Directory of Open Access Journals (Sweden)

    A. Acharyya

    2014-06-01

    Full Text Available The optimum position of the optical window (OW of illuminated lateral double-drift region (DDR impact avalanche transit time (IMPATT device has been determined subject to achieve the finest optical control of both DC and RF properties of the device. The OW is a tiny hole that has to be created on the oxide layer through which the light energy of appropriate wavelength can be coupled to the space charge region of the device. A non-sinusoidal voltage is assumed to be applied across the diode and the corresponding terminal current response is obtained from a two-dimensional (2-D large-signal (L-S simulation technique developed by the authors for illuminated lateral DDR IMPATT diode. Both the DC and L-S properties of the illuminated device based on Si, designed to operate at W-band frequencies (75 – 110 GHz are obtained from the said L-S simulation. Simulation is carried out for different incident optical power levels of different wavelengths (600 – 1000 nm by varying the position of the fixed sized OW on the oxide layer along the direction of electrical conduction of the device. Results show that, the most favorable optical tuning can be achieved when the OW is entirely created over the p-type depletion layer, i.e. when the photocurrent is purely electron dominated. Also the 700 nm wavelength is found to be most suitable wavelength for obtaining the maximum optical modulation of both DC and RF properties of the device.

  20. Optical measuring system with an interrogator and a polymer-based single-mode fibre optic sensor system

    DEFF Research Database (Denmark)

    2017-01-01

    The present invention relates to an optical measuring system comprising a polymer-based single-mode fibre-optic sensor system (102), an optical interrogator (101), and an optical arrangement (103) interconnecting the optical interrogator (101) and the polymer-based single-mode fibre-optic sensor...... system (102). The invention further relates to an optical interrogator adapted to be connected to a polymer-based single-mode fibre-optic sensor system via an optical arrangement. The interrogator comprises a broadband light source arrangement (104) and a spectrum analysing arrangement which receives...... and analyses light reflected from the polymer-based single- mode fibre-optic sensor system....

  1. Extremely low-loss single-mode photonic crystal fiber in the terahertz regime

    DEFF Research Database (Denmark)

    Islam, Raonaqul; Hasanuzzaman, G. K M; Sadath, Md Anwar

    2015-01-01

    This paper presents an updated design and numerical characterization of a rotated porous-core hexagonal photonic crystal fiber (PCF) for single-mode terahertz (THz) wave guidance. The simulation results are found using an efficient finite element method (FEM) which show a better and ultra......-low effective absorption loss of 0.045 cm-1 at 1 THz and a more flattened dispersion of 0.74±0.07ps/THz/cm in a wider bandwidth (0.54-1.36 THz) than the previously reported results. Besides, the single-mode region has been extended up to 1.74 THz (previously up to 1.3 THz) which is advantageous for wideband THz...

  2. Quantum discord dynamics of two qubits in single-mode cavities

    International Nuclear Information System (INIS)

    Wang Chen; Chen Qing-Hu

    2013-01-01

    The dynamics of quantum discord for two identical qubits in two independent single-mode cavities and a common single-mode cavity are discussed. For the initial Bell state with correlated spins, while the entanglement sudden death can occur, the quantum discord vanishes only at discrete moments in the independent cavities and never vanishes in the common cavity. Interestingly, quantum discord and entanglement show opposite behavior in the common cavity, unlike in the independent cavities. For the initial Bell state with anti-correlated spins, quantum discord and entanglement behave in the same way for both independent cavities and a common cavity. It is found that the detunings always stabilize the quantum discord. (general)

  3. Design and prototyping of self-centering optical single-mode fiber alignment structures

    International Nuclear Information System (INIS)

    Ebraert, Evert; Gao, Fei; Thienpont, Hugo; Van Erps, Jürgen; Beri, Stefano; Watté, Jan

    2016-01-01

    The European Commission’s goal of providing each European household with at least a 30 Mb s −1 Internet connection by 2020 would be facilitated by a widespread deployment of fibre-to-the-home, which would in turn be sped up by the development of connector essential components, such as high-precision alignment features. Currently, the performance of state-of-the-art physical contact optical fiber connectors is limited by the tolerance on the cladding of standard telecom-grade single-mode fiber (SMF), which is typically smaller than  ±1 μ m. We propose to overcome this limit by developing micro-spring-based self-centering alignment structures (SCAS) for SMF-connectors. We design these alignment structures with robustness and low-cost replication in mind, allowing for large-scale deployment. Both theoretical and finite element analysis (FEA) models are used to determine the optimal dimensions of the beams of which the micro-springs of the SCAS are comprised. Two topologies of the SCAS, consisting of three and four micro-springs respectively, are investigated for two materials: polysulfone (PSU) and polyetherimide (PEI). These materials hold great potential for high-performance fiber connectors while being compatible with low-cost production and with the harsh environmental operation conditions of those connectors. The theory and FEA agree well (<3% difference) for a simple micro-spring. When including a pedestal on the micro-spring (to bring it further away from the fiber) and for shorter spring lengths the agreement worsens. This is due to spring compression effects not being taken into account in our theoretical model. Prototypes are successfully fabricated using deep proton writing and subsequently characterized. The controlled insertion of an SMF in the SCAS is investigated and we determine that a force of 0.11 N is required. The fiber insertion also causes an out-of-plane deformation of the micro-springs in the SCAS of about 7 μ m, which is no

  4. BRIEF COMMUNICATIONS: Investigation of the state of polarization of light in a single-mode fiber waveguide

    Science.gov (United States)

    Kozel, S. M.; Kreopalov, V. I.; Listvin, V. N.; Glavatskikh, N. A.

    1983-01-01

    An analysis is made of the polarization anisotropy of a single-mode fiber with a twisted elliptic core. The Jones matrix is obtained and the complex function of the state of polarization of light in a fiber is investigated. The results are reported of measurements of the linear and circular birefringence of a borosilicate single-mode glass fiber.

  5. Low-bending loss and single-mode operation in few-mode optical fiber

    Science.gov (United States)

    Yin, Ping; Wang, Hua; Chen, Ming-Yang; Wei, Jin; Cai, Zhi-Min; Li, Lu-Ming; Yang, Ji-Hai; Zhu, Yuan-Feng

    2016-10-01

    The technique of eliminating the higher-order modes in a few-mode optical fiber is proposed. The fiber is designed with a group of defect modes in the cladding. The higher-order modes in the fiber can be eliminated by bending the fiber to induce strong coupling between the defect modes and the higher-order modes. Numerical simulation shows the bending losses of the LP01 mode are lower than 1.5×10-4 dB/turn for the wavelength shorter than 1.625 μm. The proposed fiber can be bent multiple turns at small bending radius which are preferable for FTTH related applications.

  6. Enhancement of single mode operation in coaxial optical waveguide using DB boundary conditions

    Science.gov (United States)

    Lohia, Pooja; Prajapati, Y.; Saini, J. P.; Rai, B. S.

    2014-11-01

    In this study, a competent numerical strategy to compute the dispersion of optical waveguides is presented and propagation of electromagnetic waves in a coaxial optical waveguide with DB boundary conditions is instigated. For this intend, cylindrical coordinates are here being used to derive the DB boundary conditions and to obtain field components for the modes. The propagation constant for the waveguide to be studied is determined by solving the Bessel and the modified Bessel functions. The cutoff frequencies for various lower order modes have been calculated and their dispersion characteristics are plotted correspondingly. The behavior of the coaxial optical waveguide under DB boundary conditions is shown to be significantly different from that of coaxial optical waveguide and conventional optical waveguide under traditional or tangential boundary conditions. Finally, the effect of waveguide dimensions on the mode cutoff frequencies and fabrication issues are also addressed.

  7. Investigation of bending loss in a single-mode optical fibre

    Indian Academy of Sciences (India)

    (glass) used for making optical fibres is about 26.211 Pa. Since radii of the core and cladding in the single-mode fibre used were 4.5 and 62.5 µm respectively, by changing θ/l, loss due to torsion stress on the core and the clad was investigated. Variation of loss against torsion stress is given in figures 10 and 11 for the core ...

  8. Combined effect of viscosity and vorticity on single mode Rayleigh-Taylor instability bubble growth

    International Nuclear Information System (INIS)

    Banerjee, Rahul; Mandal, Labakanta; Roy, S.; Khan, M.; Gupta, M. R.

    2011-01-01

    The combined effect of viscosity and vorticity on the growth rate of the bubble associated with single mode Rayleigh-Taylor instability is investigated. It is shown that the effect of viscosity on the motion of the lighter fluid associated with vorticity accumulated inside the bubble due to mass ablation may be such as to reduce the net viscous drag on the bubble exerted by the upper heavier fluid as the former rises through it.

  9. In-Line Fiber Optic Interferometric Sensors in Single-Mode Fibers

    OpenAIRE

    De-Wen Duan; Min Liu; Di Wu; Tao Zhu

    2012-01-01

    In-line fiber optic interferometers have attracted intensive attention for their potential sensing applications in refractive index, temperature, pressure and strain measurement, etc. Typical in-line fiber-optic interferometers are of two types: Fabry-Perot interferometers and core-cladding-mode interferometers. It’s known that the in-line fiber optic interferometers based on single-mode fibers can exhibit compact structures, easy fabrication and low cost. In this paper, ...

  10. A single mode method for the analysis and identification of nonlinear MDOF systems

    Science.gov (United States)

    Huang, Liping; Iwan, W. D.

    In order to apply mode approach to describe a nonlinear system, the concept of modal response of nonlinear systems is examined, and an amplitude-dependent modal model is presented based on an analysis of a single mode of response. The effectiveness of this model is examined under different types and various levels of excitation. A corresponding identification procedure for cubic systems is proposed and applied to the analysis of a 3DOF soltening nonlinear system.

  11. Optical transmission through a polarization preserving single mode optical fiber at two Ar(+) laser wavelengths

    Science.gov (United States)

    Tedjojuwono, Ken K.; Hunter, William W., Jr.

    1989-01-01

    The transmission characteristics of two Ar(+) laser wavelengths through a twenty meter Panda type Polarization Preserving Single Mode Optical Fiber (PPSMOF) were measured. The measurements were done with both single and multi-longitudinal mode radiation. In the single longitudinal mode case, a degrading Stimulated Brillouin Scattering (SBS) is observed as a backward scattering loss. By choosing an optimum coupling system and manipulating the input polarization, the threshold of the SBS onset can be raised and the transmission efficiency can be increased.

  12. Efficient multi-mode to single-mode conversion in a 61 port photonic lantern

    DEFF Research Database (Denmark)

    Noordegraaf, Danny; Skovgaard, Peter M. W.; Dybendahl Maack, Martin

    2010-01-01

    We demonstrate the fabrication of a multi-mode (MM) to 61 port single-mode (SM) splitter or "Photonic Lantern". Low port count Photonic Lanterns were first described by Leon-Saval et al. (2005). These are based on a photonic crystal fiber type design, with air-holes defining the multi-mode fiber ...... of astrophotonics for coupling MM star-light to an ensemble of SM fibers in order to perform fiber Bragg grating based spectral filtering....

  13. Terahertz light-emitting graphene-channel transistor toward single-mode lasing

    Directory of Open Access Journals (Sweden)

    Yadav Deepika

    2018-03-01

    Full Text Available A distributed feedback dual-gate graphene-channel field-effect transistor (DFB-DG-GFET was fabricated as a current-injection terahertz (THz light-emitting laser transistor. We observed a broadband emission in a 1–7.6-THz range with a maximum radiation power of ~10 μW as well as a single-mode emission at 5.2 THz with a radiation power of ~0.1 μW both at 100 K when the carrier injection stays between the lower cutoff and upper cutoff threshold levels. The device also exhibited peculiar nonlinear threshold-like behavior with respect to the current-injection level. The LED-like broadband emission is interpreted as an amplified spontaneous THz emission being transcended to a single-mode lasing. Design constraints on waveguide structures for better THz photon field confinement with higher gain overlapping as well as DFB cavity structures with higher Q factors are also addressed towards intense, single-mode continuous wave THz lasing at room temperature.

  14. Single Mode ZnO Whispering-Gallery Submicron Cavity and Graphene Improved Lasing Performance.

    Science.gov (United States)

    Li, Jitao; Lin, Yi; Lu, Junfeng; Xu, Chunxiang; Wang, Yueyue; Shi, Zengliang; Dai, Jun

    2015-07-28

    Single-mode ultraviolet (UV) laser of ZnO is still in challenge so far, although it has been paid great attention along the past decades. In this work, single-mode lasing resonance was realized in a submicron-sized ZnO rod based on serially varying the dimension of the whispering-gallery mode (WGM) cavities. The lasing performance, such as the lasing quality factor (Q) and the lasing intensity, was remarkably improved by facilely covering monolayer graphene on the ZnO submicron-rod. The mode structure evolution from multimodes to single-mode was investigated systematically based on the total internal-wall reflection of the ZnO microcavities. Graphene-induced optical field confinement and lasing emission enhancement were revealed, indicating an energy coupling between graphene SP and ZnO exciton emission. This result demonstrated the response of graphene in the UV wavelength region and extended its potential applications besides many previous reports on the multifunctional graphene/semiconductor hybrid materials and devices in advanced electronics and optoelectronics areas.

  15. High-power actively Q-switched single-mode 1342 nm Nd:YVO4 ring laser, injection-locked by a cw single-frequency microchip laser.

    Science.gov (United States)

    Koch, Peter; Bartschke, Juergen; L'huillier, Johannes A

    2015-11-30

    In this paper we report on the realization of a single-mode Q-switched Nd:YVO4 ring laser at 1342 nm. Unidirectional and single-mode operation of the ring laser is achieved by injection-locking with a continuous wave Nd:YVO4 microchip laser, emitting a single-frequency power of up to 40 mW. The ring laser provides a single-mode power of 13.9 W at 10 kHz pulse repetition frequency with a pulse duration of 18.2 ns and an excellent beam quality (M2 laser, a power of 8.7 W at 671 nm with a pulse duration of 14.8 ns and a beam propagation factor of M2 < 1.1 is obtained. The 671 nm radiation features a long-term spectral width of 75 MHz.

  16. Effects of underwater turbulence on laser beam propagation and coupling into single-mode optical fiber.

    Science.gov (United States)

    Hanson, Frank; Lasher, Mark

    2010-06-01

    We characterize and compare the effects of turbulence on underwater laser propagation with theory. Measurements of the coupling efficiency of the focused beam into a single-mode fiber are reported. A simple tip-tilt control system, based on the position of the image centroid in the focal plane, was shown to maintain good coupling efficiency for a beam radius equal to the transverse coherence length, r(0). These results are relevant to high bandwidth communication technology that requires good spatial mode quality.

  17. Multi-mode to single-mode conversion in a 61 port photonic lantern

    DEFF Research Database (Denmark)

    Noordegraaf, Danny; Skovgaard, Peter M.W.; Maack, Martin D.

    2010-01-01

    Efficient multi-mode (MM) to single-mode (SM) conversion in a 61 port splitter or “Photonic Lantern” is demonstrated. The coupling loss from a 100 µm core diameter MM section to an ensemble of 61 SM fibers and back to another 100 µm core MM section is measured to be as low as 0.76 dB. This demons......B. This demonstration shows the feasibility of using the Photonic Lanterns within the field of astrophotonics for coupling MM star-light to an ensemble of SM fibers in order to perform fiber Bragg grating based spectral filtering."...

  18. Simple immunoglobulin G sensor based on thin core single-mode fiber

    Science.gov (United States)

    Zheng, Yingfang; Lang, Tingting; Shen, Tingting; Shen, Changyu

    2018-03-01

    In this paper, a simple fiber biosensor (FOB) for immunoglobulin G (IgG) detection is designed and experimentally verified. The FOB is constructed by a 20 mm long thin core single-mode fiber (TCSMF) sandwiched between two single-mode optical fibers (SMFs). First, the refractive index (RI) sensitivity of the fiber structures is calculated by the beam propagation method. The refractive index sensing experiment is performed using different concentrations of glycerol solutions, and the experimental results are mostly consistent with the simulation predictions. The experimental RI sensitivity increases with the surrounding RI and reaches 82.7 nm/RIU. Then the surface of the FOB is functionalized by APTES for covalent bonding. The human IgG and goat anti-human IgG are chosen as a bioconjugated pair to examine the bio-sensing effectiveness of this FOB. The sensitivity of IgG detection is determined to be 10.4 nm/(mg/ml). And the serum IgG concentration in normal adults lies within the range of 6-16 mg/ml (Worsfold et al., 1985), so the sensor is applicable to human IgG monitoring. The specificity of the FOB is also verified by a contrast experiment conducted using rabbit immunoglobulin G. The proposed FOB is simple, low loss, cost-effective, and can be used for various biological and chemical applications.

  19. Optical access network using centralized light source, single-mode fiber + broad wavelength window multimode fiber

    Science.gov (United States)

    Yam, Scott S.-H.; Kim, Jaedon; Gutierrez, David; Achten, Frank

    2006-08-01

    Access networks based on a single-mode fiber (SMF) using a centralized light source (CLS) have attracted much attention recently due to their wavelength management flexibility and potential for cost reduction at customers' premises. Future networks, in addition, are likely to contain segments of multimode fiber (MMF), whose core dimension is relatively large in comparison with its single-mode counterpart, substantially reducing fiber alignment constraints and the subsequent network construction and installation cost. In this study, a CLS-based passive optical network (PON) is proposed, which will use a new generation of high-performance MMF optimized for a broad wavelength transmission window spanning from 1300to1550 nm, with a bandwidth distance product (BDP) of 40 Gbit/s-km. The proposed architecture is implemented in a test bed, and its performance is verified by bit error ratio (BER) measurement. Results show that we can implement high-performance CLS-based PONs containing both an SMF and an MMF infrastructure, simultaneously.

  20. Bend-insensitive single-mode photonic crystal fiber with ultralarge effective area for dual applications

    Science.gov (United States)

    Islam, Md. Asiful; Alam, M. Shah

    2013-05-01

    A novel photonic crystal fiber (PCF) having circular arrangement of cladding air holes has been designed and numerically optimized to obtain a bend insensitive single mode fiber with large mode area for both wavelength division multiplexing (WDM) communication and fiber-to-the-home (FTTH) application. The bending loss of the proposed bent PCF lies in the range of 10-3 to 10-4 dB/turn or lower over 1300 to 1700 nm, and 2 × 10-4 dB/turn at the wavelength of 1550 nm for a 30-mm bend radius with a higher order mode (HOM) cut-off frequency below 1200 nm for WDM application. When the whole structure of the PCF is scaled down, a bending loss of 6.78×10-4 dB/turn at 1550 nm for a 4-mm bend radius is obtained, and the loss remains in the order of 10-4 dB/turn over the same range of wavelength with an HOM cut-off frequency below 700 nm, and makes the fiber useful for FTTH applications. Furthermore, this structure is also optimized to show a splice loss near zero for fusion-splicing to a conventional single-mode fiber (SMF).

  1. Single mode fiber array for planet detection using a visible nulling interferometer

    Science.gov (United States)

    Liu, Duncan; Levine, B. Martin; Shao, Michael; Aguayo, Franciso

    2005-01-01

    We report the design, fabrication, and testing of a coherent large mode field diameter fiber array to be used as a spatial filter in a planet finding visible nulling interferometer. The array is a key component of a space instrument for visible-light detection and spectroscopy of Earth like extrasolar planets. In this concept, a nulling interferometer is synthesized from a pupil image of a single aperture which is then spatially filtered by a coherent array of single mode fibers to suppress the residual scattered star light. The use of the fiber array preserves spatial information between the star and planet. The fiber array uses a custom commercial large mode field or low NA step-index single mode fiber to relax alignment tolerances. A matching custom micro lens array is used to couple light into the fibers, and to recollimate the light out of the fiber array. The use of large mode field diameter fiber makes the fabrication of a large spatial filter array with 300 to 1000 elements feasible.

  2. Processing of complex shapes with single-mode resonant frequency microwave applicators

    International Nuclear Information System (INIS)

    Fellows, L.A.; Delgado, R.; Hawley, M.C.

    1994-01-01

    Microwave processing is an alternative to conventional composite processing techniques. Single-mode microwave applicators efficiently couple microwave energy into the composite. The application of the microwave energy is greatly affected by the geometry of the composite. In the single mode microwave applicator, two types of modes are available. These modes are best suited to processing flat planar samples or cylindrical samples with geometries that align with the electric fields. Mode-switching is alternating between different electromagnetic modes with the intelligent selection of the modes to alleviate undesirable temperature profiles. This method has improved the microwave heating profiles of materials with complex shapes that do not align with either type of electric field. Parts with two different complex geometries were fabricated from a vinyl toluene/vinyl ester resin with a continuous glass fiber reinforcement by autoclaving and by microwave techniques. The flexural properties of the microwave processed samples were compared to the flexural properties of autoclaved samples. The trends of the mechanical properties for the complex shapes were consistent with the results of experiments with flat panels. This demonstrated that mode-switching techniques are as applicable for the complex shapes as they are for the simpler flat panel geometry

  3. Single-mode annular chirally-coupled core fibers for fiber lasers

    Science.gov (United States)

    Zhang, Haitao; Hao, He; He, Linlu; Gong, Mali

    2018-03-01

    Chirally-coupled core (CCC) fiber can transmit single fundamental mode and effectively suppresses higher-order mode (HOM) propagation, thus improve the beam quality. However, the manufacture of CCC fiber is complicated due to its small side core. To decrease the manufacture difficulty in China, a novel fiber structure is presented, defined as annular chirally-coupled core (ACCC) fiber, replacing the small side core by a larger side annulus. In this paper, we designed the fiber parameters of this new structure, and demonstrated that the new structure has a similar property of single mode with traditional CCC fiber. Helical coordinate system was introduced into the finite element method (FEM) to analyze the mode field in the fiber, and the beam propagation method (BPM) was employed to analyze the influence of the fiber parameters on the mode loss. Based on the result above, the fiber structure was optimized for efficient single-mode transmission, in which the core diameter is 35 μm with beam quality M2 value of 1.04 and an optical to optical conversion efficiency of 84%. In this fiber, fundamental mode propagates in an acceptable loss, while the HOMs decay rapidly.

  4. Fibre-Bragg-grating writing in single-mode optical fibres by UV femtosecond pulses

    International Nuclear Information System (INIS)

    Zagorul'ko, K A; Kryukov, P G; Dianov, Evgenii M; Dragomir, A; Nikogosyan, D N

    2003-01-01

    Fibre-Bragg-grating writing in single-mode optical fibres by the phase-mask method using 220-fs, 264-nm UV pulses of intensity 31 - 77 GW cm -2 is reported for the first time. The achieved degree of modulation of the photoinduced refractive index was 1.9 x 10 -3 in an H 2 -loaded SMF-28 telecommunication fibre and 1.1 x 10 -3 in a H 2 -free Nufern GF1 fibre. The dependence of the induced refractive index on the intensity for the same irradiation fluences in the case of the H 2 -loaded SMF-28 fibre shows that the refractive index is induced due to nonlinear absorption. (letters)

  5. Electrically tunable Brillouin fiber laser based on a metal-coated single-mode optical fiber

    Directory of Open Access Journals (Sweden)

    S.M. Popov

    Full Text Available We explore tunability of the Brillouin fiber laser employing Joule heating. For this purpose, 10-m-length of a metal-coated single-mode optical cavity fiber has been directly included into an electrical circuit, like a conductor wire. With the current up to ∼3.5 A the laser tuning is demonstrated over a spectrum range of ∼400 MHz. The observed laser line broadening up to ∼2 MHz is explained by frequency drift and mode-hoping in the laser caused by thermal noise. Keywords: Brillouin fiber laser, Metal-coated optical fiber, Laser tuning, Fiber sensors

  6. Three-dimensional single-mode nonlinear ablative Rayleigh-Taylor instability

    International Nuclear Information System (INIS)

    Yan, R.; Aluie, H.; Betti, R.; Sanz, J.; Liu, B.; Frank, A.

    2016-01-01

    The nonlinear evolution of the single-mode ablative Rayleigh-Taylor instability is studied in three dimensions. As the mode wavelength approaches the cutoff of the linear spectrum (short-wavelength modes), it is found that the three-dimensional (3D) terminal bubble velocity greatly exceeds both the two-dimensional (2D) value and the classical 3D bubble velocity. Unlike in 2D, the 3D short-wavelength bubble velocity does not saturate. The growing 3D bubble acceleration is driven by the unbounded accumulation of vorticity inside the bubble. The vorticity is transferred by mass ablation from the Rayleigh-Taylor spikes to the ablated plasma filling the bubble volume

  7. Thermal Effects on the Single-Mode Regime of Distributed Modal Filtering Rod Fiber

    DEFF Research Database (Denmark)

    Coscelli, Enrico; Poli, Federica; Alkeskjold, Thomas Tanggaard

    2012-01-01

    Power scaling of fiber laser systems requires the development of innovative active fibers, capable of providing high pump absorption, ultralarge effective area, high-order mode suppression, and resilience to thermal effects. Thermally induced refractive index change has been recently appointed...... rod-type photonic crystal fiber, which exploits resonant coupling with high-index elements to suppress high-order modes, are thoroughly investigated. A computationally efficient model has been developed to calculate the refractive index change due to the thermo-optical effect, and it has been...... integrated into a full-vector modal solver based on the finite-element method to obtain the guided modes, considering different heating conditions. Results have shown that the single-mode regime of the distributed modal filtering fiber is less sensitive to thermal effects with respect to index-guiding fibers...

  8. Development of a 10-decade single-mode reactor flux monitoring system

    Energy Technology Data Exchange (ETDEWEB)

    Valentine, K.H.; Shepard, R.L.; Falter, K.G.; Reese, W.B.

    1988-03-31

    Conventional wide-range neutron channels employ three optional modes to monitor the required flux range from source levels to full power (typically 10 or more decades). Difficult calibrations are necessary to provide a continuous output signal when such a system switches from counting mode in the source range to mean-square voltage mode in the midrange to dc current mode in the power range. In an ORNL proof-of-principle test, a method of extended range counting was implemented with a fission counter and conventional wide-band pulse processing electronics to provide a single-mode, monotonically increasing signal that spanned /approximately 10/ decades of neutron flux. Ongoing work includes design, fabrication, and testing of a comlpete neutron flux monitoring system suitable for advanced liquid metal reactor designs. 6 refs., 4 figs.

  9. 2-kW single-mode fiber laser employing bidirectional-pump scheme

    Science.gov (United States)

    Zhang, Fan; Zheng, Wenyou; Shi, Pengyang; Zhang, Xinhai

    2018-01-01

    2kW single-mode fiber laser with two cascade home-made cladding light strippers (CLSs) by employing bidirectionalpump scheme has been demonstrated. 2.009 kW signal power is obtained when pump power is 2.63 kW and the slope efficiency is 76.6%. Raman Stokes light is less than -47 dB at 2.009 kW even with a 10-m delivery fiber with core/inner cladding diameter of 20/400um. The beam quality M2stability of +/-0.14% is achieved by special thermal management for a more uniform temperature distribution on the Yb-doped gain fiber.

  10. Stability of the single-mode output of a laser diode array with phase conjugate feedback

    DEFF Research Database (Denmark)

    Juul Jensen, S.; Løbel, M.; Petersen, P.M.

    2000-01-01

    . The output power and the center wavelength are found to be extremely stable in a 100 h stability measurement. External feedback of the output beam into the laser is seen to decrease both the spatial and the temporal coherence of the output significantly. We outline an approach to obtain a stable single......The stability of the output of a single-mode laser diode array with frequency selective phase conjugate feedback has been investigated experimentally. Both the long-term stability of the laser output and the sensitivity to feedback generated by external reflection of the output beam are examined......-mode output when external feedback is present using spatial filtering in the path of the output beam. (C) 2000 American Institute of Physics....

  11. Optimizing single mode robustness of the distributed modal filtering rod fiber amplifier

    DEFF Research Database (Denmark)

    Jørgensen, Mette Marie; Petersen, Sidsel Rübner; Laurila, Marko

    2012-01-01

    High-power fiber amplifiers for pulsed applications require large mode area (LMA) fibers having high pump absorption and near diffraction limited output. Photonic crystal fibers allow realization of short LMA fiber amplifiers having high pump absorption through a pump cladding that is decoupled...... from the outer fiber diameter. However, achieving ultra low NA for single mode (SM) guidance is challenging, thus different design strategies must be applied. The distributed modal filtering (DMF) design enables SM guidance in ultra low NA fibers with very large cores, where large preform tolerances...... can be compensated during the fiber draw. Design optimization of the SM bandwidth of the DMF rod fiber is presented. Analysis of band gap properties results in a fourfold increase of the SM bandwidth compared to previous results, achieved by utilizing the first band of cladding modes, which can cover...

  12. 1540-nm single frequency single-mode pulsed all fiber laser for coherent Doppler lidar

    Science.gov (United States)

    Zhang, Xin; Diao, Weifeng; Liu, Yuan; Liu, Jiqiao; Hou, Xia; Chen, Weibiao

    2015-02-01

    A single-mode single frequency eye-safe pulsed all fiber laser based on master oscillator power amplification structure is presented. This laser is composed of a narrow linewidth distributed laser diode seed laser and two-stage cascade amplifiers. 0.8 m longitudinally gradient strained erbium/ytterbium co-doped polarization-maintaining fiber with a core diameter of 10 μm is used as the gain fiber and two acoustic-optics modulators are adopted to enhance pulse extinction ratio. A peak power of 160 W and a pulse width of 200 ns at 10 kHz repetition rate are achieved with transform-limited linewidth and diffraction-limited beam quality. This laser will be employed in a compact short range coherent Doppler wind lidar.

  13. A long-baseline interferometer employing single-mode fiber optics

    Science.gov (United States)

    Shaklan, Stuart

    The idea of the Fiber-Linked Optical Array Telescope proposed by Connes (1987) is to mount several small optical telescopes around the perimeter of a radio dish or other large steerable structure, couple the light into single-mode (SM) fibers, and use the fibers to coherently combine the beams at the output. This paper examines the important properties of SM fibers and then discusses the whole system in general terms, starting with the telescopes and following the light through to the detectors, along with the results of laboratory experiments evaluating the performance of SM fibers. The imaging capabilities of the array were simulated, and it was found that, using 10 telescopes on a 440-m dish, the array obtains images with resolution of the order of 2 milliarc seconds in the visible range.

  14. Development of a 10-decade single-mode reactor flux monitoring system

    International Nuclear Information System (INIS)

    Valentine, K.H.; Shepard, R.L.; Falter, K.G.; Reese, W.B.

    1988-01-01

    Conventional wide-range neutron channels employ three optional modes to monitor the required flux range from source levels to full power (typically 10 or more decades). Difficult calibrations are necessary to provide a continuous output signal when such a system switches from counting mode in the source range to mean-square voltage mode in the midrange to dc current mode in the power range. In an ORNL proof-of-principle test, a method of extended range counting was implemented with a fission counter and conventional wide-band pulse processing electronics to provide a single-mode, monotonically increasing signal that spanned /approximately 10/ decades of neutron flux. Ongoing work includes design, fabrication, and testing of a comlpete neutron flux monitoring system suitable for advanced liquid metal reactor designs. 6 refs., 4 figs

  15. Interaction of a single mode field cavity with the 1D XY model: Energy spectrum

    International Nuclear Information System (INIS)

    Tonchev, H; Donkov, A A; Chamati, H

    2016-01-01

    In this work we use the fundamental in quantum optics Jaynes-Cummings model to study the response of spin 1/2chain to a single mode of a laser light falling on one of the spins, a focused interaction model between the light and the spin chain. For the spin-spin interaction along the chain we use the XY model. We report here the exact analytical results, obtained with the help of a computer algebra system, for the energy spectrum in this model for chains of up to 4 spins with nearest neighbors interactions, either for open or cyclic chain configurations. Varying the sign and magnitude of the spin exchange coupling relative to the light-spin interaction we have investigated both cases of ferromagnetic or antiferromagnetic spin chains. (paper)

  16. Laser direct micro-machining with top-hat-converted single mode lasers

    Science.gov (United States)

    Homburg, O.; Toennissen, F.; Mitra, T.; Lissotschenko, V.

    2008-02-01

    Laser direct micro-machining processes are used in a variety of industries like inkjet printing, semiconductor processing, solar technology, flat-panel display production and medicine. Various kinds of materials, e.g. ceramics, metals, isolators, oxides, organics and semiconductors are being structured. In most cases pulsed single mode solid state lasers with an inhomogeneous Gaussian beam profile are employed, like YAG lasers and their harmonics. However, the quality and functionality of the generated structures and micro-systems as well as the speed of the process can be improved by the utilization of homogeneous top hat profiles. The beam shaping principle of refractive Gaussian-to-top-hat converters is shown. Compact beam shaper modules based on this principle have been developed - supporting most direct laser micro-machining applications. The resulting process advantages are demonstrated by selected application results, namely the drilling of holes and patterning of trenches for different kinds of materials.

  17. Interferometric measurement of refractive index modification in a single mode microfiber

    Science.gov (United States)

    Ahmed, Farid; Ahsani, Vahid; Jun, Martin B. G.

    2017-02-01

    Efficient and cost effective measurement of the refractive index profile in an optical fiber is a significant technical job to design and manufacture in-fiber photonic devices and communication systems. For instance, to design fiber gratings, it is required to estimate the refractive index modulation to be inscribed by the fabrication apparatus such as ultraviolet or infrared lasers. Mach-Zehnder interferometer (MZI) based quantification of refractive index change written in single mode microfiber by femtosecond laser radiation is presented in this study. The MZI is constructed by splicing a microfiber (core diameter: 3.75 μm, cladding diameter: 40 μm) between standard single mode fibers. To measure the RI inscribed by infrared femtosecond laser, 200 μm length of the core within the MZI was scanned with laser radiation. As the higher index was written within 200 μm length of the core, the transmission spectrum of the interferometer displayed a corresponding red shift. The observed spectral shift was used to calculate the amount of refractive index change inscribed by the femtosecond irradiation. For the MZI length of 3.25 mm, and spectral shift of 0.8 nm, the calculated refractive index was found to be 0.00022. The reported results display excellent agreement between theory and experimental findings. Demonstrated method provides simple yet very effective on-site measurement of index change in optical fibers. Since the MZI can be constructed in diverse fiber types, this technique offers flexibility to quantify index change in various optical fibers.

  18. Interpreting Adaptation to Concurrent Compared with Single-Mode Exercise Training: Some Methodological Considerations.

    Science.gov (United States)

    Fyfe, Jackson J; Loenneke, Jeremy P

    2018-02-01

    Incorporating both endurance and resistance training into an exercise regime is termed concurrent training. While there is evidence that concurrent training can attenuate resistance training-induced improvements in maximal strength and muscle hypertrophy, research findings are often equivocal, with some suggesting short-term concurrent training may instead further enhance muscle hypertrophy versus resistance training alone. These observations have questioned the validity of the purported 'interference effect' on muscle hypertrophy with concurrent versus single-mode resistance training. This article aims to highlight some methodological considerations when interpreting the concurrent training literature, and, in particular, the degree of changes in strength and muscle hypertrophy observed with concurrent versus single-mode resistance training. Individual training status clearly influences the relative magnitude and specificity of both training adaptation and post-exercise molecular responses in skeletal muscle. The training status of participants is therefore likely a key modulator of the degree of adaptation and interference seen with concurrent training interventions. The divergent magnitudes of strength gain versus muscle hypertrophy induced by resistance training also suggests most concurrent training studies are likely to observe more substantial changes in (and in turn, any potential interference to) strength compared with muscle hypertrophy. Both the specificity and sensitivity of measures used to assess training-induced changes in strength and muscle hypertrophy also likely influence the interpretation of concurrent training outcomes. Finally, the relative importance of any modulation of hypertrophic versus strength adaptation with concurrent training should be considered in context with the relevance of training-induced changes in these variables for enhancing athletic performance and/or functional capacity. Taken together, these observations suggest that

  19. Data driven modeling of the low-Atwood single-mode Rayleigh-Taylor instability

    Science.gov (United States)

    Hutchinson, Maxwell

    The Rayleigh-Taylor instability is one of the most common and well studied phenomena in fluid dynamics. Despite research dating to the late 19th century, the non-linear dynamics of the interfacial instability are still not fully understood, particularly in the case when the two fluids have nearly the same density. It was recently demonstrated in this, the low-Atwood regime, that the idealized single-mode problem departs from established potential flow models in the form of a re-acceleration beyond the predicted terminal interface velocity. This thesis is an attempt to model that re-acceleration and, more broadly, the late time dynamics of the single-mode low-Atwood Rayleigh-Taylor instability. The approach taken here is based on buoyancy-drag models, which express a force balance between buoyancy and parasitic drag. The dynamical buoyancy-drag model is supplemented with a mixing model that dilutes the buoyant force over time. These models are written deliberately generally, with 8 unique coefficients. Three of these coefficients are solved for by equating the early time behavior with that of well established linear theories. The remaining 5 coefficients are estimated by relating them to drag coefficients, friction factors, and geometric ratios in the interface shape. To evaluate the model and compute the 5 unknown coefficients more precisely, a set of direct numerical simulations are performed over the relevant parameter space. These simulations are first validated against experimental data. Then they are shown to converge and their resolutions are chosen such as to minimize computational cost given the accuracy scale of the model. The 5 coefficients are fit to the resulting data set, and the model achieves better than 2% error in the bubble height and 4% error in the volume of mixed fluid. Three coefficients are nominally independent of the parameterization of the problem, while two are shown to vary with the Rayleigh number and the diffusivity.

  20. High temperature, single mode, long infrared (λ = 17.8 μm) InAs-based quantum cascade lasers

    Energy Technology Data Exchange (ETDEWEB)

    Chastanet, D.; Bousseksou, A., E-mail: adel.bousseksou@u-psud.fr; Julien, F. H.; Colombelli, R., E-mail: raffaele.colombelli@u-psud.fr [Institut d' Electronique Fondamentale, Univ. Paris Sud, UMR 8622 CNRS, 91405 Orsay (France); Lollia, G.; Bahriz, M.; Baranov, A. N.; Teissier, R., E-mail: roland.teissier@ies.univ-montp2.fr [Institut d' Electronique du Sud, Univ. Montpellier 2, UMR 5214 CNRS, 34095 Montpellier (France)

    2014-09-15

    We demonstrate quantum cascade lasers in the InAs/AlSb material system which operate up to 333 K (in pulsed regime) at λ = 17.8 μm. They employ metal-metal optical waveguides and the threshold current density is 1.6 kA/cm{sup 2} at 78 K. We also report distributed-feedback devices obtained using the same laser material via a 1{sup st}-order Bragg grating inscribed in the sole top metallic contact. Spectral single mode operation with more than 20 dB side mode suppression ratio is achieved at a temperature of 300 K. Large wavelength tuning rates, of the order of 1.5 nm/K, are demonstrated. A wavelength coverage of 0.38 μm is achieved in single-mode regime over a temperature range of 255 K.

  1. 26 nJ picosecond solitons from thulium-doped single-mode master oscillator power fiber amplifier.

    Science.gov (United States)

    Renard, William; Canat, Guillaume; Bourdon, Pierre

    2012-02-01

    We report on an all single-mode master oscillator power fiber amplifier delivering high energy picosecond solitons at 1960 nm. The Bragg stabilized and self-starting oscillator delivers 62 pJ transform-limited pulses at 11.2 MHz pulse repetition frequency. Solitons are amplified in a core-pumped single-mode heavily thulium-doped fiber up to 26 nJ. The average and peak power are 291 mW and 7.4 kW, respectively. Pulses remain transform limited without significant self-phase-modulation distortion. We discuss the limitations of picosecond pulse amplification in a core-pumped single-mode fiber amplifier.

  2. Toward single-mode random lasing within a submicrometre-sized spherical ZnO particle film

    International Nuclear Information System (INIS)

    Niyuki, Ryo; Fujiwara, Hideki; Sasaki, Keiji; Ishikawa, Yoshie; Koshizaki, Naoto; Tsuji, Takeshi

    2016-01-01

    We had recently reported unique random laser action such as quasi-single-mode and low-threshold lasing from a submicrometre-sized spherical ZnO nanoparticle film with polymer particles as defects. The present study demonstrates a novel approach to realize single-mode random lasing by adjusting the sizes of the defect particles. From the dependence of random lasing properties on defect size, we find that the average number of lasing peaks can be modified by the defect size, while other lasing properties such as lasing wavelengths and thresholds remain unchanged. These results suggest that lasing wavelengths and thresholds are determined by the resonant properties of the surrounding scatterers, while the defect size stochastically determines the number of lasing peaks. Therefore, if we optimize the sizes of the defects and scatterers, we can intentionally induce single-mode lasing even in a random structure (Fujiwara et al 2013 Appl. Phys. Lett. 102 061110). (paper)

  3. Application of Single-Mode Fiber-Coupled Receivers in Optical Satellite to High-Altitude Platform Communications

    Directory of Open Access Journals (Sweden)

    Fidler Franz

    2008-01-01

    Full Text Available Abstract In a free-space optical communication system employing fiber-optic components, the phasefront distortions induced by atmospheric turbulence limit the efficiency with which the laser beam is coupled into a single-mode fiber. We analyze different link scenarios including a geostationary (GEO satellite, a high-altitude platform (HAP, and an optical ground station (OGS. Single-mode coupled optically preamplified receivers allow for efficient suppression of background noise and highly sensitive detection. While GEO-to-OGS communication suffers from atmospheric turbulence, we demonstrate that GEO-to-HAP communication allows for close to diffraction-limited performance when applying tip-tilt correction.

  4. Application of Single-Mode Fiber-Coupled Receivers in Optical Satellite to High-Altitude Platform Communications

    Directory of Open Access Journals (Sweden)

    Oswald Wallner

    2008-05-01

    Full Text Available In a free-space optical communication system employing fiber-optic components, the phasefront distortions induced by atmospheric turbulence limit the efficiency with which the laser beam is coupled into a single-mode fiber. We analyze different link scenarios including a geostationary (GEO satellite, a high-altitude platform (HAP, and an optical ground station (OGS. Single-mode coupled optically preamplified receivers allow for efficient suppression of background noise and highly sensitive detection. While GEO-to-OGS communication suffers from atmospheric turbulence, we demonstrate that GEO-to-HAP communication allows for close to diffraction-limited performance when applying tip-tilt correction.

  5. Comparison of high power large mode area and single mode 1908nm Tm-doped fiber lasers

    Science.gov (United States)

    Johnson, Benjamin R.; Creeden, Daniel; Limongelli, Julia; Pretorius, Herman; Blanchard, Jon; Setzler, Scott D.

    2016-03-01

    We compare large mode area (LMA) and single-mode (SM) double-clad fiber geometries for use in high power 1908nm fiber lasers. With a simple end-pumped architecture, we have generated 100W of 1908nm power with LMA fiber at 40% optical efficiency and 117W at 52.2% optical efficiency with single-mode fiber. We show the LMA fiber is capable of generating >200W and the SM fiber is capable of >300W at 1908nm. In all cases, the fiber lasers are monolithic power-oscillators with no free-space coupling.

  6. Influence of photo- and thermal bleaching on pre-irradiation low water peak single mode fibers

    Science.gov (United States)

    Yin, Jianchong; Wen, Jianxiang; Luo, Wenyun; Xiao, Zhongyin; Chen, Zhenyi; Wang, Tingyun

    2011-12-01

    Reducing the radiation-induced transmission loss in low water peak single mode fiber (LWP SMF) has been investigated by using photo-bleaching method with 980nm pump light source and using thermal-bleaching method with temperature control system. The results show that the radiation-induced loss of pre-irradiation optical fiber can be reduced effectively with the help of photo-bleaching or thermal-bleaching. Although the effort of photo-bleaching is not as significant as thermal-bleaching, by using photo-bleaching method, the loss of fiber caused by radiation-induced defects can be reduced best up to 49% at 1310nm and 28% at 1550nm in low pre-irradiation condition, the coating of the fiber are not destroyed, and the rehabilitating time is just several hours, while self-annealing usually costs months' time. What's more, the typical high power LASER for photo-bleaching can be 980nm pump Laser Diode, which is very accessible.

  7. Artificially controlled backscattering in single mode fibers based on femtosecond laser fabricated reflectors

    Science.gov (United States)

    Wang, Xiaoliang; Chen, Daru; Li, Haitao; Wu, Qiong

    2018-04-01

    A novel method to artificially control the backscattering of the single-mode fiber (SMF) is proposed and investigated for the first time. This method can help to fabricate a high backscattering fiber (HBSF), such as by fabricating reflectors in every one meter interval of an SMF based on the exposure of the femtosecond laser beam. The artificially controlled backscattering (ACBS) can be much higher than the natural Rayleigh backscattering (RB) of the SMF. The RB power and ACBS power in the unit length fiber are derived according to the theory of the RBS. The total relative power and the relative back power reflected in the unit length of the HBSF have been simulated and presented. The simulated results show that the HBSF has the characteristics of both low optical attenuation and high backscattering. The relative back power reflected in the unit length of the HBSF is 25dB larger than the RB power of the SMF when the refractive index modulation quantity of the reflectors is 0.009. Some preliminary experiments also indicate that the method fabricating reflectors to increase the backscattering power of the SMF is practical and promising.

  8. Single-mode Rayleigh-Taylor growth-rate measurements with the OMEGA laser system

    International Nuclear Information System (INIS)

    Knauer, J.P.; Verdon, C.P.; Meyerhofer, D.D.; Boehly, T.R.; Bradley, D.K.; Smalyuk, V.A.; Ofer, D.; McKenty, P.W.; Glendinning, S.G.; Kalantar, D.H.; Watt, R.G.; Gobby, P.L.; Willi, O.; Taylor, R.J.

    1997-01-01

    The results from a series of single-mode Rayleigh-Taylor (RT) instability growth experiments performed on the OMEGA laser system using planar targets are reported. Planar targets with imposed mass perturbations were accelerated using five to six 351-nm laser beams overlapped with total intensities up to 2.5x10 14 W/cm 2 . Experiments were performed with both 3-ns ramp and 3-ns flat-topped temporal pulse shapes. The use of distributed phase plates and smoothing by spectral dispersion resulted in a laser-irradiation nonuniformity of 4%endash 7% over a 600-μm-diam region defined by the 90% intensity contour. The temporal growth of the modulation in optical depth was measured using through-foil radiography and was detected with an x-ray framing camera for CH targets with and without a foam buffer. The growth of both 31-μm and 60-μm wavelength perturbations was found to be in good agreement with ORCHID simulations when the experimental details, including noise, were included. The addition of a 30-mg/cc, 100-μm-thick polystyrene foam buffer layer resulted in reduced growth of the 31-μm perturbation and essentially unchanged growth for the 60-μm case when compared to targets without foam. copyright 1997 American Institute of Physics

  9. Spontaneous emission of two quantum dots in a single-mode cavity

    International Nuclear Information System (INIS)

    Qiu Liu; Zhang Ke; Li Zhi-Yuan

    2013-01-01

    The spontaneous emission spectrum from two quantum dots (QDs) that are strongly coupled with a single-mode nanocavity is investigated using rigorous numerical calculations and simple analytical solutions of quantum dynamics. The emission spectra both from the side and along the axis of the cavity are considered. Modification of two parameters, the coupling strength and the detuning between the transition frequencies of the two quantum dots, allows us to efficiently control the shape of the spontaneous emission spectrum. Different profiles and their physical origins can be well understood in the dressed-state picture for the light—QD interaction in the on-resonance and off-resonance situations. In the on-resonance situation, the emission spectra exhibit symmetric features, and they are not altered by the asymmetry in the coupling parameters. The axis spectra show two emission peaks while the side spectra have three emission peaks. In the off-resonance situation, the emission spectra always show an asymmetrical three-peak feature. When the two QDs have different decay parameters, singular features (a peak or a dip) can take place at the frequency of the cavity mode, and this is attributed to the unbalanced process of the emission and absorption of a single photon. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

  10. All-fiber single-mode high modulation rate pseudorandom-coded laser

    Science.gov (United States)

    Zhang, Xin; Yang, Fang; Liu, Yuan; He, Yan; Hou, Xia; Chen, Weibiao

    2013-12-01

    An all-fiber high modulation speed pseudorandom-coded laser based on master oscillator power amplifier configuration is proposed. We use a high modulation rate distributed feedback laser diode as the seed laser to generate the original pseudorandom pulse train. The modulation rate is 1 Gb/s, which corresponds to a minimum pulse interval of 1 ns. A 1 kHz repetition frequency of 10-order M-sequence pseudorandom pulse train is chosen to balance on-line data processing speed and laser ranging resolution. Then, the pseudorandom pulse train is amplified by two-stage amplifiers to boost the output power. All components used in the amplifiers are built in single mode (SM) fiber, so the final output laser is SM with excellent beam quality. Finally, the peak power of pseudorandom code laser is amplified to 23.6 W from 1.5 mW without wave distortion, corresponding to a gain of 42 dB. The ranging experiment of using the optical fiber delay method indoors shows the transmitter of combining modulated laser diode and multistage fiber amplifiers as a promising solution for developing laser for pseudorandom-coded laser ranging.

  11. Trapped-ion anomalous diffusion coefficient on the basis of single mode saturation

    International Nuclear Information System (INIS)

    Koshi, Yuji; Hatayama, Akiyoshi; Ogasawara, Masatada.

    1982-03-01

    Expressions of the anomalous diffusion coefficient due to the dissipative trapped ion instability (DTII) are derived for the case with and without the effect of magnetic shear. Derivation is made by taking into account of the single mode saturation of the DTII previously obtained numerically. In the absence of the shear effect, the diffusion coefficient is proportional to #betta#sub(i)a 2 (#betta#sub(i) is the effective collision frequency of the trapped ions and a is the minor radius of a torus) and is much larger than the neoclassical ion heat conductivity. In the presence of the shear effect, the diffusion coefficient is much smaller than the Kadomtsev and Pogutse's value and is the same order of magnitude as the neoclassical ion heat conductivity. Dependences of the diffusion coefficient on the temperature and on the total particle number density are rather complicated due to the additional spectral cut-off, which is introduced to regularize the short wavelength modes in the numerical analysis. (author)

  12. Piezoelectric transducer parameter selection for exciting a single mode from multiple modes of Lamb waves

    International Nuclear Information System (INIS)

    Zhang Hai-Yan; Yu Jian-Bo

    2011-01-01

    Excitation and propagation of Lamb waves by using rectangular and circular piezoelectric transducers surface-bonded to an isotropic plate are investigated in this work. Analytical stain wave solutions are derived for the two transducer shapes, giving the responses of these transducers in Lamb wave fields. The analytical study is supported by a numerical simulation using the finite element method. Symmetric and antisymmetric components in the wave propagation responses are inspected in detail with respect to test parameters such as the transducer geometry, the length and the excitation frequency. By placing only one piezoelectric transducer on the top or the bottom surface of the plate and weakening the strength of one mode while enhancing the strength of the other modes to find the centre frequency, with which the peak wave amplitude ratio between the S0 and A0 modes is maximum, a single mode excitation from the multiple modes of the Lamb waves can be achieved approximately. Experimental data are presented to show the validity of the analyses. The results are used to optimize the Lamb wave detection system. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

  13. Computational investigation of single mode vs multimode Rayleigh endash Taylor seeding in Z-pinch implosions

    International Nuclear Information System (INIS)

    Douglas, M.R.; Deeney, C.; Roderick, N.F.

    1998-01-01

    A series of two-dimensional magnetohydrodynamic calculations have been carried out to investigate single and multimode growth and mode coupling for magnetically-driven Rayleigh endash Taylor instabilities in Z pinches. Wavelengths ranging from 5.0 mm down to 1.25 mm were considered. Such wavelengths are comparable to those observed at stagnation using a random density open-quotes seedingclose quotes method. The calculations show that wavelengths resolved by less than 10 cells exhibit an artificial decrease in initial Fourier spectrum amplitudes and a reduction in the corresponding amplitude growth. Single mode evolution exhibits linear exponential growth and the development of higher harmonics as the mode transitions into the nonlinear phase. The mode growth continues to exponentiate but at a slower rate than determined by linear hydrodynamic theory. In the two and three mode case, there is clear evidence of mode coupling and inverse cascade. In addition, distinct modal patterns are observed late in the implosion, resulting from finite shell thickness and magnetic field effects. copyright 1998 American Institute of Physics. thinsp

  14. Role of third-order dispersion in chirped Airy pulse propagation in single-mode fibers

    Science.gov (United States)

    Cai, Wangyang; Wang, Lei; Wen, Shuangchun

    2018-04-01

    The dynamic propagation of the initial chirped Airy pulse in single-mode fibers is studied numerically, special attention being paid to the role of the third-order dispersion (TOD). It is shown that for the positive TOD, the Airy pulse experiences inversion irrespective of the sign of initial chirp. The role of TOD in the dynamic propagation of the initial chirped Airy pulse depends on the combined sign of the group-velocity dispersion (GVD) and the initial chirp. If the GVD and chirp have the opposite signs, the chirped Airy pulse compresses first and passes through a breakdown area, then reconstructs a new Airy pattern with opposite acceleration, with the breakdown area becoming small and the main peak of the new Airy pattern becoming asymmetric with an oscillatory structure due to the positive TOD. If the GVD and chirp have the same signs, the finite-energy Airy pulse compresses to a focal point and then inverses its acceleration, in the case of positive TOD, the distance to the focal point becoming smaller. At zero-dispersion point, the finite-energy Airy pulse inverses to the opposite acceleration at a focal point, with the tight-focusing effect being reduced by initial chirp. Under the effect of negative TOD, the initial chirped Airy pulse disperses and the lobes split. In addition, in the anomalous dispersion region, for strong nonlinearity, the initial chirped Airy pulse splits and enters a soliton shedding regime.

  15. Experimental demonstration of single-mode fiber coupling over relatively strong turbulence with adaptive optics.

    Science.gov (United States)

    Chen, Mo; Liu, Chao; Xian, Hao

    2015-10-10

    High-speed free-space optical communication systems using fiber-optic components can greatly improve the stability of the system and simplify the structure. However, propagation through atmospheric turbulence degrades the spatial coherence of the signal beam and limits the single-mode fiber (SMF) coupling efficiency. In this paper, we analyze the influence of the atmospheric turbulence on the SMF coupling efficiency over various turbulences. The results show that the SMF coupling efficiency drops from 81% without phase distortion to 10% when phase root mean square value equals 0.3λ. The simulations of SMF coupling with adaptive optics (AO) indicate that it is inevitable to compensate the high-order aberrations for SMF coupling over relatively strong turbulence. The SMF coupling efficiency experiments, using an AO system with a 137-element deformable mirror and a Hartmann-Shack wavefront sensor, obtain average coupling efficiency increasing from 1.3% in open loop to 46.1% in closed loop under a relatively strong turbulence, D/r0=15.1.

  16. BEND-INDUCED LOSSES IN A SINGLE-MODE MICROSTRUCTURED FIBER WITH A LARGE CORE

    Directory of Open Access Journals (Sweden)

    Y. A. Gatchin

    2015-03-01

    Full Text Available A study of bend-induced losses in a silica-based single-mode microstructured fiber with a core diameter ranging from 20 to 35 microns and increased relative air content in the holey cladding has been conducted. With the use of the equivalent step-index profile method in approximation of waveguide parameters of microstructured fiber (normalized frequency and normalized transverse attenuation constant the effect of bending on the spectral position of the fundamentalmode short-wavelength leakage boundary has been analyzed. Upon measurement of spectral characteristics of attenuation in the considered fibers good accordance of numerical and experimental data has been found out. It is shown that increase of the air content in the holey cladding leads to expansion of the mentioned boundary to lower wavelengths for the value from 150 to 800 nm depending on the core size and bending conditions. A single-transverse-mode propagation is achieved on fiber length of 5-10 meters due to a substantial difference in losses of fundamental and higher-order guided modes attained by bending. Optical losses in all studied samples are less than 10 dB/km at the wavelength λ = 1550 nm. The results of the study can be applied in the design of high-power laser systems having such basic requirements as a relatively large mode spot and high beam quality.

  17. A Novel Technique for Sterilization Using a Power Self-Regulated Single-Mode Microwave Cavity

    Directory of Open Access Journals (Sweden)

    Juan D. Reverte-Ors

    2017-06-01

    Full Text Available In this paper, a novel technique to achieve precise temperatures in food sterilization has been proposed. An accurate temperature profile is needed in order to reach a commitment between the total removal of pathogens inside the product and the preservation of nutritional and organoleptic characteristics. The minimal variation of the target temperature in the sample by means of a monitoring and control software platform, allowing temperature stabilization over 100 °C, is the main goal of this work. A cylindrical microwave oven, under pressure conditions and continuous control of the microwave supply power as function of the final temperature inside the sample, has been designed and developed with conditions of single-mode resonance. The uniform heating in the product is achieved by means of sample movement and the self-regulated power control using the measured temperature. Finally, for testing the sterilization of food with this technology, specific biological validation based on Bacillus cereus as a biosensor of heat inactivation has been incorporated as a distribution along the sample in the experimental process to measure the colony-forming units (CFUs for different food samples (laboratory medium, soup, or fish-based animal by-products. The obtained results allow the validation of this new technology for food sterilization with precise control of the microwave system to ensure the uniform elimination of pathogens using high temperatures.

  18. Impact of quantum–classical correspondence on entanglement enhancement by single-mode squeezing

    International Nuclear Information System (INIS)

    Joseph, Sijo K.; Chew, Lock Yue; Sanjuán, Miguel A.F.

    2014-01-01

    Quantum entanglement between two field modes can be achieved through the collective squeezing of the two respective modes. If single-mode squeezing is performed prior to such a two-mode squeezing, an enhancement of entanglement production can happen. Interestingly, the occurrence of this enhancement can be implicitly linked to the local classical dynamical behavior via the paradigm of quantum–classical correspondence. In particular, the entanglement generated through quantum chaos is found to be hardly enhanced by prior squeezing, since it is bounded by the saturation value of the maximally entangled Schmidt state with fixed energy. These results illustrate that entanglement enhancement via initial squeezing can serve as a useful indicator of quantum chaotic behaviour. - Highlights: • Continuous-variable entanglement is explored in the Pullen–Edmonds Hamiltonian. • The local phase-space structure and the entanglement enhancement are related. • Entanglement enhancement via squeezing is smaller for the chaotic orbit. • Entanglement enhancement via squeezing is higher for the regular orbit. • The magnitude of the entanglement enhancement serves as a quantum-chaos indicator

  19. Stable single-mode distributed feedback quantum cascade lasers at λ ∼ 4.25 μm with low power consumption

    Science.gov (United States)

    Jia, Zhiwei; Wang, Lijun; Zhang, Jinchuan; Liu, Fengqi; Zhuo, Ning; Zhai, Shenqiang; Liu, Junqi; Wang, Zhanguo

    2016-10-01

    Short-wavelength (4.25 μm) distributed-feedback quantum cascade laser operating in continuous wave (cw) mode at room temperature with low power consumption was presented. Stable single-mode operation with a side-mode-suppression-ratio above 25 dB was maintained for the whole measured current and temperature range by enlarging gain difference and strong grating coupling. Because of the strong coupling, very low threshold current and power consumption were achieved. For a device of 9-μm-wide and 2-mm-long, the cw threshold current and power consumption at 293 K were as low as 126 mA and 1.45 W, respectively. All results above were from the device without using buried heterostructure geometry.

  20. Comparative investigation of methods to determine the group velocity dispersion of an endlessly single-mode photonic crystal fiber

    Science.gov (United States)

    Baselt, Tobias; Popp, Tobias; Nelsen, Bryan; Lasagni, Andrés. Fabián.; Hartmann, Peter

    2017-05-01

    Endlessly single-mode fibers, which enable single mode guidance over a wide spectral range, are indispensable in the field of fiber technology. A two-dimensional photonic crystal with a silica central core and a micrometer-spaced hexagonal array of air holes is an established method to achieve endless single-mode guidance. There are two possible ways to determine the dispersion: measurement and calculation. We calculate the group velocity dispersion GVD based on the measurement of the fiber structure parameters, the hole diameter and the pitch of a presumed homogeneous hexagonal array and compare the calculation with two methods to measure the wavelength-dependent time delay. We measure the time delay on a three hundred meter test fiber with a homemade supercontinuum light source, a set of bandpass filters and a fast detector and compare the results with a white light interferometric setup. To measure the dispersion of optical fibers with high accuracy, a time-frequency-domain setup based on a Mach-Zehnder interferometer is used. The experimental setup allows the determination of the wavelength dependent differential group delay of light travelling through a thirty centimeter piece of test fiber in the wavelength range from VIS to NIR. The determination of the GVD using different methods enables the evaluation of the individual methods for characterizing the endlessly single-mode fiber.

  1. Open quantum systems and the two-level atom interacting with a single mode of the electromagnetic field

    International Nuclear Information System (INIS)

    Sandulescu, A.; Stefanescu, E.

    1987-07-01

    On the basis of Lindblad theory of open quantum systems we obtain new optical equations for the system of two-level atom interacting with a single mode of the electromagnetic field. The conventional Block equations in a generalized form with field phases are obtained in the hypothesis that all the terms are slowly varying in the rotating frame.(authors)

  2. Q-switching and efficient harmonic generation from a single-mode LMA photonic bandgap rod fiber laser

    DEFF Research Database (Denmark)

    Laurila, Marko; Saby, Julien; Alkeskjold, Thomas T.

    2011-01-01

    We demonstrate a Single-Mode (SM) Large-Mode-Area (LMA) ytterbium-doped PCF rod fiber laser with stable and close to diffraction limited beam quality with 110W output power. Distributed-Mode-Filtering (DMF) elements integrated in the cladding of the rod fiber provide a robust spatial mode with a ...

  3. A passive micromachined device for alignment of arrays of single-mode fibers for hermetic photonic packaging - the CLASP concept

    Energy Technology Data Exchange (ETDEWEB)

    Seigal, P.K.; Kravitz, S.H.; Word, J.C.; Bauer, T.M. [and others

    1997-02-01

    A micro-machined fiber alignment device, called CLASP (Capture and Locking Alignment Spring Positioner) has been fabricated. It uses a nickel leaf spring to passively capture vertical arrays of single-mode fibers with {approximately} 2 {mu}m accuracy.

  4. Model of a single mode energy harvester and properties for optimal power generation

    International Nuclear Information System (INIS)

    Liao Yabin; Sodano, Henry A

    2008-01-01

    The process of acquiring the energy surrounding a system and converting it into usable electrical energy is termed power harvesting. In the last few years, the field of power harvesting has experienced significant growth due to the ever increasing desire to produce portable and wireless electronics with extended life. Current portable and wireless devices must be designed to include electrochemical batteries as the power source. The use of batteries can be troublesome due to their finite energy supply, which necessitates their periodic replacement. In the case of wireless sensors that are to be placed in remote locations, the sensor must be easily accessible or of disposable nature to allow the device to function over extended periods of time. Energy scavenging devices are designed to capture the ambient energy surrounding the electronics and covert it into usable electrical energy. The concept of power harvesting works towards developing self-powered devices that do not require replaceable power supplies. The development of energy harvesting systems is greatly facilitated by an accurate model to assist in the design of the system. This paper will describe a theoretical model of a piezoelectric based energy harvesting system that is simple to apply yet provides an accurate prediction of the power generated around a single mode of vibration. Furthermore, this model will allow optimization of system parameters to be studied such that maximal performance can be achieved. Using this model an expression for the optimal resistance and a parameter describing the energy harvesting efficiency will be presented and evaluated through numerical simulations. The second part of this paper will present an experimental validation of the model and optimal parameters

  5. Single-mode, Rayleigh-Taylor growth-rate measurements on the OMEGA laser system

    International Nuclear Information System (INIS)

    Knauer, J. P.; Betti, R.; Bradley, D. K.; Boehly, T. R.; Collins, T. J. B.; Goncharov, V. N.; McKenty, P. W.; Meyerhofer, D. D.; Smalyuk, V. A.; Verdon, C. P.

    2000-01-01

    The results from a series of single-mode, Rayleigh-Taylor (RT) instability growth experiments performed on the OMEGA laser system [T. R. Boehly et al., Opt. Commun. 133, 495 (1997)] using planar targets are reported. Planar targets with imposed mass perturbations were accelerated using five or six 351 nm laser beams overlapped with total intensities up to 2.5x10 14 W/cm 2 . Experiments were performed with both 3 ns ramp and 3 ns flat-topped temporal pulse shapes. The use of distributed phase plates and smoothing by spectral dispersion resulted in a laser-irradiation nonuniformity of 4%-7% over a 600 μm diam region defined by the 90% intensity contour. The temporal growth of the modulation in optical depth was measured using throughfoil radiography and was detected with an x-ray framing camera for CH targets. Two-dimensional (2-D) hydrodynamic simulations (ORCHID) [R. L. McCrory and C. P. Verdon, in Inertial Confinement Fusion (Editrice Compositori, Bologna, 1989), pp. 83-124] of the growth of 20, 31, and 60 μm wavelength perturbations were in good agreement with the experimental data when the experimental details, including noise, were included. The amplitude of the simulation optical depth is in good agreement with the experimental optical depth; therefore, great care must be taken when the growth rates are compared to dispersion formulas. Since the foil's initial condition just before it is accelerated is not that of a uniformly compressed foil, the optical density measurement does not accurately reflect the amplitude of the ablation surface but is affected by the initial nonuniform density profile. (c) 2000 American Institute of Physics

  6. A comparative study of the single-mode Richtmyer-Meshkov instability

    Science.gov (United States)

    Bai, X.; Deng, X.-L.; Jiang, L.

    2017-11-01

    In this work, the single-mode Richtmyer-Meshkov instability is studied numerically to find a reasonable nonlinear theoretical model which can be applied to predict the interface evolution from the linear stage to the early nonlinear stage. The cut-cell-based sharp-interface methods MuSiC+ (Chang et al. in J Comput Phys 242:946-990, 2013) and CCGF (Bai and Deng in Adv Appl Math Mech 9(5):1052-1075, 2017) are applied to generate numerical results for comparisons. Classical Air-SF6 and Air-Helium conditions are applied in this study, and initial amplitude and Atwood number are varied for comparison. Comparisons to the simulation results from the literature show the applicability of MuSiC+ and CCGF. Comparisons to the nonlinear theoretical models show that ZS (Zhang and Sohn in Phys Lett A 212:149-155, 1996; Phys Fluids 9:1106-1124, 1997), SEA (Sadot et al. in Phys Rev Lett 80:1654-1657, 1998), and DR (Dimonte and Ramaprabhu in Phys Fluids 22:014104, 2010) models are valid for both spike and bubble growth rates, and MIK (Mikaelian in Phys Rev E 67:026319, 2003) and ZG (Zhang and Guo in J Fluid Mech 786:47-61, 2016) models are valid for bubble growth rate, when the initial perturbation is small and the Atwood number is low, but only the DR model is applicable for both spike and bubble growth rates when the initial perturbation amplitude and the Atwood number are large. A new term of non-dimensional initial perturbation amplitude is presented and multiplied to the DR model to get a unified fitted DR model, which gives consistent results to the simulation ones for small and large initial amplitudes.

  7. Toward photostable multiplex analyte detection on a single mode planar optical waveguide

    Energy Technology Data Exchange (ETDEWEB)

    Mukundan, Harshini [Los Alamos National Laboratory; Xei, Hongshi [Los Alamos National Laboratory; Anderson, Aaron S [Los Alamos National Laboratory; Grace, Wynne K [Los Alamos National Laboratory; Martinez, Jennifer S [NON LANL; Swanson, Basil [Los Alamos National Laboratory

    2009-01-01

    We have developed a waveguide-based optical biosensor for the sensitive and specific detection of biomarkers associated with disease. Our technology combines the superior optical properties of single-mode planar waveguides, the robust nature of functionalized self-assembled monolayer sensing films and the specificity of fluorescence sandwich immunoassays to detect biomarkers in complex biological samples such as serum, urine and sputum. We have previously reported the adaptation of our technology to the detection of biomarkers associated with breast cancer and anthrax. However, these approaches primarily used phospholipid bilayers as the functional film and organic dyes (ex: AlexaFluors) as the fluorescence reporter. Organic dyes are easily photodegraded and are not amenable to multiplexing because of their narrow Stokes' shift. Here we have developed strategies for conjugation of the detector antibodies with quantum dots for use in a multiplex detection platform. We have previously evaluated dihydroxylipoic acid quantum dots for the detection of a breast cancer biomarker. In this manuscript, we investigate the detection of the Bacillus anthracis protective antigen using antibodies conjugated with polymer-coated quantum dots. Kinetics of binding on the waveguide-based biosensor is reported. We compare the sensitivity of quantum dot labeled antibodies to those labeled with AlexaFluor and demonstrate the photostability of the former in our assay platform. In addition, we compare sulfydryl labeling of the antibody in the hinge region to that of nonspecific amine labeling. This is but the first step in developing a multiplex assay for such biomarkers on our waveguide platform.

  8. Tm3+-doped barium gallo-germanate glass single-mode fiber with high gain per unit length for ultracompact 1.95 µm laser

    Science.gov (United States)

    Tang, Guowu; Wen, Xin; Huang, Kaimin; Qian, Guoquan; Lin, Wei; Cheng, Huihui; Jiang, Licheng; Qian, Qi; Yang, Zhongmin

    2018-03-01

    Heavily Tm3+-doped barium gallo-germanate glass single-mode (SM) fibers were successfully drawn. A gain per unit length of 3.6 dB/cm at 1.95 µm was obtained. To the best of our knowledge, this is the highest gain per unit length reported for Tm3+-doped germanate glass SM fibers. A single-frequency fiber laser operating at 1.95 µm has been built using a 1.5-cm-long active fiber pumped by a 1568 nm fiber laser. The direct output power from the ultracompact laser cavity is 227 mW. The results show that the fibers are highly promising for high-power and ultracompact single-frequency laser applications.

  9. Investigation of single-mode and multi-mode hydromagnetic Rayleigh-Taylor instability in planar geometry

    International Nuclear Information System (INIS)

    Roderick, N.F.; Cochrane, K.; Douglas, M.R.

    1998-01-01

    Previous investigations carried out to study various methods of seeding the hydromagnetic Rayleigh-Taylor instability in magnetohydrodynamic simulations showed features similar to those seen in hydrodynamic calculations. For periodic single-mode initiations the results showed the appearance of harmonics as the single modes became nonlinear. For periodic multi-mode initiations new modes developed that indicated the presence of mode coupling. The MHD simulations used parameters of the high velocity large radius z-pinch experiments performed in the Z-accelerator at Sandia National Laboratories. The cylindrical convergent geometry and variable acceleration of these configurations made comparison with analytic, developed for planar geometry with constant acceleration, difficult. A set of calculations in planar geometry using constant current to produce acceleration and parameters characteristic of the cylindrical implosions has been performed to allow a better comparison. Results of these calculations, comparison with analytic theory, and comparison with the cylindrical configuration calculations will be discussed

  10. The use of Lorentz group formalism in solving polarization effects of a birefringent single mode optical fiber

    International Nuclear Information System (INIS)

    Ishiekwene, G.C.; Brown, C.S.; Mensah, S.Y.; Bak, A.E.

    2000-07-01

    A theoretical analysis on the polarization effects of a light beam propagating in a birefringent single-mode fiber is presented. We derive a system of differential equations representing the evolution of Stokes parameters and illustrate their application to polarization effects in a straight birefringent single mode optical fiber. The solutions to the set of equations are obtained using specifically the methods of the unified formalism for polarization optics which adopt the use of the Stokes-Mueller equation and the Lorentz group to model polarization phenomena in media such as optical fibers. The analytical results presented using this approach are identical to results obtained from other conventional methods. We observe the characteristic exponential decrease in the total intensity of the input light due to attenuation by the fiber. (author)

  11. Sub-micrometre accurate free-form optics by three-dimensional printing on single-mode fibres

    Science.gov (United States)

    Gissibl, Timo; Thiele, Simon; Herkommer, Alois; Giessen, Harald

    2016-01-01

    Micro-optics are widely used in numerous applications, such as beam shaping, collimation, focusing and imaging. We use femtosecond 3D printing to manufacture free-form micro-optical elements. Our method gives sub-micrometre accuracy so that direct manufacturing even on single-mode fibres is possible. We demonstrate the potential of our method by writing different collimation optics, toric lenses, free-form surfaces with polynomials of up to 10th order for intensity beam shaping, as well as chiral photonic crystals for circular polarization filtering, all aligned onto the core of the single-mode fibres. We determine the accuracy of our optics by analysing the output patterns as well as interferometrically characterizing the surfaces. We find excellent agreement with numerical calculations. 3D printing of microoptics can achieve sufficient performance that will allow for rapid prototyping and production of beam-shaping and imaging devices. PMID:27339700

  12. Combined single-mode/multimode fiber link supporting simplified in-building 60-GHz gigabit wireless access

    DEFF Research Database (Denmark)

    Pham, Tien Thang; Lebedev, Alexander; Beltrán, Marta

    2012-01-01

    In this paper, we propose and experimentally demonstrate a simple, cost-effective hybrid gigabit fiber-wireless system for in-building wireless access. Simplicity and cost-effectiveness are achieved in all parts of the system by utilizing direct laser modulation, optical frequency up-conversion, ......In this paper, we propose and experimentally demonstrate a simple, cost-effective hybrid gigabit fiber-wireless system for in-building wireless access. Simplicity and cost-effectiveness are achieved in all parts of the system by utilizing direct laser modulation, optical frequency up......-conversion, combined single mode/multimode fiber transmission and envelope detection. Error-free transmission of 2-Gbps data in 60-GHz band over a composite channel including 10-km standard single-mode fiber (SSMF)/1-km multimode fiber (MMF) and 6.5-m air transmission was successfully achieved....

  13. Sub-micrometre accurate free-form optics by three-dimensional printing on single-mode fibres

    Science.gov (United States)

    Gissibl, Timo; Thiele, Simon; Herkommer, Alois; Giessen, Harald

    2016-06-01

    Micro-optics are widely used in numerous applications, such as beam shaping, collimation, focusing and imaging. We use femtosecond 3D printing to manufacture free-form micro-optical elements. Our method gives sub-micrometre accuracy so that direct manufacturing even on single-mode fibres is possible. We demonstrate the potential of our method by writing different collimation optics, toric lenses, free-form surfaces with polynomials of up to 10th order for intensity beam shaping, as well as chiral photonic crystals for circular polarization filtering, all aligned onto the core of the single-mode fibres. We determine the accuracy of our optics by analysing the output patterns as well as interferometrically characterizing the surfaces. We find excellent agreement with numerical calculations. 3D printing of microoptics can achieve sufficient performance that will allow for rapid prototyping and production of beam-shaping and imaging devices.

  14. Quantum dynamics of a BEC interacting with a single-mode quantized field in the presence of interatom collisions

    Energy Technology Data Exchange (ETDEWEB)

    Ghasemian, E. [Atomic and Molecular Group, Faculty of Physics, Yazd University, Yazd (Iran, Islamic Republic of); Tavassoly, M.K., E-mail: mktavassoly@yazd.ac.ir [Atomic and Molecular Group, Faculty of Physics, Yazd University, Yazd (Iran, Islamic Republic of); Photonics Research Group, Engineering Research Center, Yazd University, Yazd (Iran, Islamic Republic of); The Laboratory of Quantum Information Processing, Yazd University, Yazd (Iran, Islamic Republic of)

    2016-09-23

    In this paper, we consider a model in which N two-level atoms in a Bose–Einstein condensate (BEC) interact with a single-mode quantized laser field. Our goal is to investigate the quantum dynamics of atoms in the BEC in the presence of interatom interactions. To achieve the purpose, at first, using the collective angular momentum operators, we try to reduce the dynamical Hamiltonian of the system to a well-known Jaynes–Cummings like model (JCM). We also use the Dicke model to construct the state of atomic subsystem, by which the analytical solution of the system may be obtained. Then, we analyze the atomic population inversion, the degree of entanglement between the “atoms in BEC” and the “field” as well as the Mandel parameter. Numerical results show that, the atomic population inversion, atom-field entanglement and quantum statistics of photons are very sensitive to the evolved parameters in the model (and so can be well-adjusted), such as the number of atoms in BEC, the intensity of initial field, the interatom coupling constant and detuning. To investigate the entanglement properties, we pay attention to the entropy and linear entropy. It is shown that, oscillations in the two entropy criteria may be seen, with some maxima of entanglement at some moments of time. Finally, looking for the quantum statistics, we evaluate the Mandel parameter, by which we demonstrate the sub-Poissonian statistics and so the nonclassical characteristics of the field state of system. Collapse-revival phenomenon, which is a distinguishable nonclassical characteristic of the system, can be apparently observed in the atomic population inversion and the Mandel parameter. - Highlights: • N two-level atoms in a BEC interacting with a laser field in the presence of interatom interactions is considered. • The atomic population inversion, degree of entanglement between the “atoms in BEC” and the “field” and the Mandel parameter are investigated. • Collapse

  15. 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.

  16. 175 fs-long pulses from a high-power single-mode Er-doped fiber laser at 1550 nm

    Science.gov (United States)

    Elahi, Parviz; Kalaycıoğlu, Hamit; Li, Huihui; Akçaalan, Önder; Ilday, F. Ömer

    2017-11-01

    Development of Er-doped ultrafast lasers have lagged behind the corresponding developments in Yb- and Tm-doped lasers, in particular, fiber lasers. Various applications benefit from operation at a central wavelength of 1.5 μm and its second harmonic, including emerging applications such as 3D processing of silicon and 3D printing based on two-photon polymerization. We report a simple, robust fiber master oscillator power amplifier operating at 1.55 μm, implementing chirp pulse amplification using single-mode fibers for diffraction-limited beam quality. The laser generates 80 nJ pulses at a repetition rate of 43 MHz, corresponding to an average power of 3.5 W, which can be compressed down to 175 fs. The generation of short pulses was achieved using a design which is guided by numerical simulations of pulse propagation and amplification and manages to overturn gain narrowing with self-phase modulation, without invoking excessive Raman scattering processes. The seed source for the two-stage amplifier is a dispersion-managed passively mode-locked oscillator, which generates a ∼40 nm-wide spectrum and 1.7-ps linearly chirped pulses.

  17. Multistabilities and symmetry-broken one-color and two-color states in closely coupled single-mode lasers

    Science.gov (United States)

    Clerkin, Eoin; O'Brien, Stephen; Amann, Andreas

    2014-03-01

    We theoretically investigate the dynamics of two mutually coupled, identical single-mode semi-conductor lasers. For small separation and large coupling between the lasers, symmetry-broken one-color states are shown to be stable. In this case the light outputs of the lasers have significantly different intensities while at the same time the lasers are locked to a single common frequency. For intermediate coupling we observe stable symmetry-broken two-color states, where both lasers lase simultaneously at two optical frequencies which are separated by up to 150 GHz. Using a five-dimensional model, we identify the bifurcation structure which is responsible for the appearance of symmetric and symmetry-broken one-color and two-color states. Several of these states give rise to multistabilities and therefore allow for the design of all-optical memory elements on the basis of two coupled single-mode lasers. The switching performance of selected designs of optical memory elements is studied numerically.

  18. Observing Exoplanets with High-dispersion Coronagraphy. II. Demonstration of an Active Single-mode Fiber Injection Unit

    Energy Technology Data Exchange (ETDEWEB)

    Mawet, D.; Ruane, G.; Xuan, W.; Echeverri, D.; Klimovich, N.; Randolph, M.; Fucik, J.; Wang, J.; Dekany, R.; Delorme, J.-R. [Department of Astronomy, California Institute of Technology, 1200 East California Boulevard, MC 249-17, Pasadena, CA 91125 (United States); Wallace, J. K.; Vasisht, G.; Mennesson, B.; Choquet, E.; Serabyn, E., E-mail: dmawet@astro.caltech.edu [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States)

    2017-04-01

    High-dispersion coronagraphy (HDC) optimally combines high-contrast imaging techniques such as adaptive optics/wavefront control plus coronagraphy to high spectral resolution spectroscopy. HDC is a critical pathway toward fully characterizing exoplanet atmospheres across a broad range of masses from giant gaseous planets down to Earth-like planets. In addition to determining the molecular composition of exoplanet atmospheres, HDC also enables Doppler mapping of atmosphere inhomogeneities (temperature, clouds, wind), as well as precise measurements of exoplanet rotational velocities. Here, we demonstrate an innovative concept for injecting the directly imaged planet light into a single-mode fiber, linking a high-contrast adaptively corrected coronagraph to a high-resolution spectrograph (diffraction-limited or not). Our laboratory demonstration includes three key milestones: close-to-theoretical injection efficiency, accurate pointing and tracking, and on-fiber coherent modulation and speckle nulling of spurious starlight signal coupling into the fiber. Using the extreme modal selectivity of single-mode fibers, we also demonstrated speckle suppression gains that outperform conventional image-based speckle nulling by at least two orders of magnitude.

  19. Unified Scattering Parameters formalism in terms of Coupled-Mode Theory for investigating hybrid single-mode/two-mode photonic interconnects

    Directory of Open Access Journals (Sweden)

    Boucher Yann G.

    2017-01-01

    Full Text Available In terms of Linear Algebra, a directional coupler between a single-mode waveguide and a two-mode waveguide can be thought of as formally equivalent to a set of three mutually coupled single-mode waveguides. Its responses, easily derived in the frame of ternary Coupled-Mode Theory, are used to establish analytically the scattering parameters of a hybrid ring-based modal multiplexer.

  20. Experimental Performance of a Single-Mode Ytterbium-doped Fiber Ring Laser with Intracavity Modulator

    Science.gov (United States)

    Numata, Kenji; Camp, Jordan

    2012-01-01

    We have developed a linearly polarized Ytterbium-doped fiber ring laser with a single longitudinal mode output at 1064 run. A fiber-coupled intracavity phase modulator ensured mode-hop free operation and allowed fast frequency tuning. The fiber laser was locked with high stability to an iodine-stabilized laser, showing a frequency noise suppression of a factor approx 10 (exp 5) at 1 mHz

  1. Correlated motion of two atoms trapped in a single-mode cavity field

    International Nuclear Information System (INIS)

    Asboth, Janos K.; Domokos, Peter; Ritsch, Helmut

    2004-01-01

    We study the motion of two atoms trapped at distant positions in the field of a driven standing-wave high-Q optical resonator. Even without any direct atom-atom interaction the atoms are coupled through their position dependent influence on the intracavity field. For sufficiently good trapping and low cavity losses the atomic motion becomes significantly correlated and the two particles oscillate in their wells preferentially with a 90 deg. relative phase shift. The onset of correlations seriously limits cavity cooling efficiency, raising the achievable temperature to the Doppler limit. The physical origin of the correlation can be traced back to a cavity mediated crossfriction, i.e., a friction force on one particle depending on the velocity of the second particle. Choosing appropriate operating conditions allows for engineering these long range correlations. In addition this cross-friction effect can provide a basis for sympathetic cooling of distant trapped clouds

  2. Dynamics of 1.55 μm Wavelength Single-Mode Vertical-Cavity Surface-Emitting Laser Output under External Optical Injection

    Directory of Open Access Journals (Sweden)

    Kyong Hon Kim

    2012-01-01

    Full Text Available We review the temporal dynamics of the laser output spectrum and polarization state of 1.55 μm wavelength single-mode (SM vertical-cavity surface-emitting lasers (VCSELs induced by external optical beam injection. Injection of an external continuous-wave laser beam to a gain-switched SM VCSEL near the resonance wavelength corresponding to its main polarization-mode output was critical for improvement of its laser pulse generation characteristics, such as pulse timing-jitter reduction, linewidth narrowing, pulse amplitude enhancement, and pulse width shortening. Pulse injection of pulse width shorter than the cavity photon lifetime into the SM VCSEL in the orthogonal polarization direction with respect to its main polarization mode caused temporal delay of the polarization recovery after polarization switching (PS, and its delay was found to be the minimum at an optimized bias current. Polarization-mode bistability was observed even in the laser output of an SM VCSEL of a standard circularly cylindrical shape and used for all-optical flip-flop operations with set and reset injection pulses of very low pulse energy of order of the 3.5~4.5 fJ.

  3. Wavefront measurement of single-mode quantum cascade laser beam for seed application in laser-produced plasma extreme ultraviolet system.

    Science.gov (United States)

    Nowak, Krzysztof M; Ohta, Takeshi; Suganuma, Takashi; Yokotsuka, Toshio; Fujimoto, Junichi; Mizoguchi, Hakaru

    2012-12-01

    Quantum cascade laser (QCL) is a very attractive seed source for a multikilowatt pulsed CO2 lasers applied for driving extreme ultraviolet emitting plasmas. In this Letter, we investigate output beam properties of a QCL designed to address P18 and P20 lines of 10.6 micron band of CO2 molecule. In particular, output beam quality and stability are investigated for the first time. A well-defined linear polarization and a single-mode operation enabled a use of phase retrieval method for full description of QCL output beam. A direct, multi-image numerical phase retrieval technique was developed and successfully applied to the measured intensity patterns of a QCL beam. Very good agreement between the measured and reconstructed beam profiles was observed at distances ranging from QCL aperture to infinity, proving a good understanding of the beam propagation. The results also confirm a high spatial coherence and high stability of the beam parameters, the features expected from an excellent seed source.

  4. Nonlinear Phenomena in the Single-Mode Dynamics in an AFM Cantilever Beam

    KAUST Repository

    Ruzziconi, Laura

    2016-12-05

    This study deals with the nonlinear dynamics arising in an atomic force microscope cantilever beam. After analyzing the static behavior, a single degree of freedom Galerkin reduced order model is introduced, which describes the overall scenario of the structure response in a neighborhood of the primary resonance. Extensive numerical simulations are performed when both the forcing amplitude and frequency are varied, ranging from low up to elevated excitations. The coexistence of competing attractors with different characteristics is analyzed. Both the non-resonant and the resonant behavior are observed, as well as ranges of inevitable escape. Versatility of behavior is highlighted, which may be attractive in applications. Special attention is devoted to the effects of the tip-sample separation distance, since this aspect is of fundamental importance to understand the operation of an AFM. We explore the metamorphoses of the multistability region when the tip-sample separation distance is varied. To have a complete description of the AFM response, comprehensive behavior charts are introduced to detect the theoretical boundaries of appearance and disappearance of the main attractors. Also, extensive numerical simulations investigate the AFM response when both the forcing amplitude and the tip-sample separation distance are considered as control parameters. The main features are analyzed in detail and the obtained results are interpreted in terms of oscillations of the cantilever-tip ensemble. However, we note that all the aforementioned results represent the limit when disturbances are absent, which never occurs in practice. Here comes the importance of overcoming local investigations and exploring dynamics from a global perspective, by introducing dynamical integrity concepts. To extend the AFM results to the practical case where disturbances exist, we develop a dynamical integrity analysis. After performing a systematic basin of attraction analysis, integrity

  5. The entanglement of two moving atoms interacting with a single-mode field via a three-photon process

    International Nuclear Information System (INIS)

    Chao, Wu; Mao-Fa, Fang

    2010-01-01

    In this paper, the entanglement of two moving atoms induced by a single-mode field via a three-photon process is investigated. It is shown that the entanglement is dependent on the category of the field, the average photon number N, the number p of half-wave lengths of the field mode and the atomic initial state. Also, the sudden death and the sudden birth of the entanglement are detected in this model and the results show that the existence of the sudden death and the sudden birth depends on the parameter and the category of the mode field. In addition, the three-photon process is a higher order nonlinear process. (general)

  6. Optical frequency comb generation for DWDM transmission over 25- to 50-km standard single-mode fiber

    Science.gov (United States)

    Ullah, Rahat; Bo, Liu; Yaya, Mao; Ullah, Sibghat; Khan, Muhammad Saad; Tian, Feng; Ali, Amjad; Ahmad, Ibrar; Xiangjun, Xin

    2018-01-01

    Dense wavelength division multiplexed (DWDM) transmission equal to 1.2 Tbps over 25 to 50 km across standard single-mode fiber (SSMF) in the C band is performed based on an optical frequency comb generator. Sixty-one flattened optical frequency tones were realized with 30-GHz frequency spacing, high side-mode suppression ratio over 35 dB, and minimum amplitude difference was realized using amplitude modulator for first time in cascade mode with two Mach-Zehnder modulators (MZMs) where all the modulators were tailored by RF signals. 20×61 Gbps DWDM-based differential quadrature phase shift keying modulated signals were successfully transmitted over SSMF and analyze its transmission capability for range of 25 to 50 km with acceptable power penalties and bit error rates.

  7. Transmission of 2.5 Gbit/s Spectrum-sliced WDM System for 50 km Single-mode Fiber

    Science.gov (United States)

    Ahmed, Nasim; Aljunid, Sayed Alwee; Ahmad, R. Badlisha; Fadil, Hilal Adnan; Rashid, Mohd Abdur

    2011-06-01

    The transmission of a spectrum-sliced WDM channel at 2.5 Gbit/s for 50 km of single mode fiber using an system channel spacing only 0.4 nm is reported. We have investigated the system performance using NRZ modulation format. The proposed system is compared with conventional system. The system performance is characterized as the bit-error-rate (BER) received against the system bit rates. Simulation results show that the NRZ modulation format performs well for 2.5 Gbit/s system bit rates. Using this narrow channel spectrum-sliced technique, the total number of multiplexed channels can be increased greatly in WDM system. Therefore, 0.4 nm channel spacing spectrum-sliced WDM system is highly recommended for the long distance optical access networks, like the Metro Area Network (MAN), Fiber-to-the-Building (FTTB) and Fiber-to-the-Home (FTTH).

  8. Statistical properties of single-mode fiber coupling of satellite-to-ground laser links partially corrected by adaptive optics.

    Science.gov (United States)

    Canuet, Lucien; Védrenne, Nicolas; Conan, Jean-Marc; Petit, Cyril; Artaud, Geraldine; Rissons, Angelique; Lacan, Jerome

    2018-01-01

    In the framework of satellite-to-ground laser downlinks, an analytical model describing the variations of the instantaneous coupled flux into a single-mode fiber after correction of the incoming wavefront by partial adaptive optics (AO) is presented. Expressions for the probability density function and the cumulative distribution function as well as for the average fading duration and fading duration distribution of the corrected coupled flux are given. These results are of prime interest for the computation of metrics related to coded transmissions over correlated channels, and they are confronted by end-to-end wave-optics simulations in the case of a geosynchronous satellite (GEO)-to-ground and a low earth orbit satellite (LEO)-to-ground scenario. Eventually, the impact of different AO performances on the aforementioned fading duration distribution is analytically investigated for both scenarios.

  9. ANALYTICAL EXPRESSION FOR THE ELECTRIC FIELD OF THE SINGLE MODE LASER HOMOGENEOUS BROADENING IN THE PULSE REGIME

    Directory of Open Access Journals (Sweden)

    S. Ayadi

    2015-07-01

    Full Text Available The simplest model of the laser is that of a single mode system homogenously broadened. The dynamical behavior of this laser is described by three differential equations, called Haken-Lorenz equations[1],  similar to the Lorenz model [1] already known to predict deterministic chaos. In previous recent work [5-7] we have proposed a simple harmonic expansion method to obtain a series of harmonics terms that yield analytical solutions to the laser equations. ¶This method allows us to derive an analytical expression of the laser field amplitude  when this last  undergoes a  periodic oscillations around zero mean value. We also obtain an analytical expression of the pulsing frequency.

  10. High-temperature sensor based on an abrupt-taper Michelson interferometer in single-mode fiber.

    Science.gov (United States)

    Xu, Le; Jiang, Lan; Wang, Sumei; Li, Benye; Lu, Yongfeng

    2013-04-01

    This study proposes a high-temperature sensor based on an abrupt fiber-taper Michelson interferometer (FTMI) in single-mode fiber fabricated by a fiber-taper machine and electric-arc discharge. The proposed FTMI is applied to measure temperature and refractive index (RI). A high temperature sensitivity of 118.6 pm/°C is obtained in the temperature range of 500°C-800°C. The wavelength variation is only -0.335 nm for the maximum attenuation peak, with the external RI changed from 1.333 to 1.3902, which is desirable for high-temperature sensing to eliminate the cross sensitivity to RI.

  11. Analytical study of nonlinear phase shift through stimulated Brillouin scattering in single mode fiber with the pump power recycling technique

    International Nuclear Information System (INIS)

    Al-Asadi, H A; Mahdi, M A; Bakar, A A A; Adikan, F R Mahamd

    2011-01-01

    We present a theoretical study of nonlinear phase shift through stimulated Brillouin scattering in single mode optical fiber. Analytical expressions describing the nonlinear phase shift for the pump and Stokes waves in the pump power recycling technique have been derived. The dependence of the nonlinear phase shift on the optical fiber length, the reflectivity of the optical mirror and the frequency detuning coefficient have been analyzed for different input pump power values. We found that with the recycling pump technique, the nonlinear phase shift due to stimulated Brillouin scattering reduced to less than 0.1 rad for 5 km optical fiber length and 0.65 reflectivity of the optical mirror, respectively, at an input pump power equal to 30 mW

  12. Single-mode interband cascade laser sources for mid-infrared spectroscopic applications

    Science.gov (United States)

    Scheuermann, J.; von Edlinger, M.; Weih, R.; Becker, S.; Nähle, L.; Fischer, M.; Koeth, J.; Kamp, M.; Höfling, S.

    2016-05-01

    Compared to the near infrared, many technologically and industrially relevant gas species have more than an order of magnitude higher absorption features in the mid-infrared (MIR) wavelength range. These species include for example important hydrocarbons (methane, acetylene), nitrogen oxides and sulfur oxides. Tunable laser absorption spectroscopy (TLAS) has proven to be a versatile tool for gas sensing applications with significant advantages compared to other techniques. These advantages include real time measurement, standoff detection and ruggedness of the sensor. We present interband cascade lasers (ICLs), which have evolved into important laser sources for the MIR spectral range from 3 to 7 μm. ICLs achieve high efficiency by cascading optically active zones whilst using interband transitions, so they combine common diode laser as well as quantum cascade laser based technologies. Our application grade singlemode distributed feedback devices operate continuous wave at room temperature and are offering several features especially useful for high performance TLAS applications like: side mode suppression ratio of > 30 dB, continuous tuning ranges up to 30 nm, low threshold power densities and low overall power consumption. The devices are typically integrated in a thermoelectrically cooled TO-style package, hermetically sealed using a cap with anti-reflection coated window. This low power consumption as well as the compact size and ruggedness of the fabricated laser sources makes them perfectly suited for battery powered portable solutions for in field spectroscopy applications.

  13. Screening Test Procedure For Long Life Single Mode Step Index Separate Confinement Heterostructure Single Quantum Well (Sinsch-Sqw) Laser Diodes

    Science.gov (United States)

    Fritz, William J.

    1989-06-01

    An experiment was conducted to establish an effective burn-in and screening procedure for long life SINSCH-SQW laser diodes. The laser diodes were grown by MOCVD and processed with 20μ wide oxide defined stripes. The devices had a high reflective back facet coating with a small etalon bonded to a passivated front facet to ensure single mode operation. The laser diodes were bonded p-side up to copper heat sinks using indium solder. A total of 48 devices were selected prior to burn-in and were operated at 200mA constant current for 2000 hours at an average heat sink temperature of 55°C. The average initial output power was 45mW per device. At the end of the test, the output powers ranged from lmW to 85mW. Most of the devices with the low final power failed catastrophically within 24 hours from the start of the test. Many laser diodes showed very little change in output power while others degraded gradually by varying amounts. Failure analysis showed that failures were facet, bulk, or heat sink related. The temporal output power degradations (i.e., gradual degradation, etc.) can be explained by the identified failure mechanisms. From the test results and failure analysis, a screening strategy based on inspection and burn-in can be devised to reject devices that may fail early. Also, improvements in processing can provide potential yield improvements. After accounting for degradation related to processing, a very long material lifetime is predicted for these SINSCH-SQW laser diodes.

  14. Monolithic Ytterbium All-single-mode Fiber Laser with Direct Fiber-end Delivery of nJ-level Femtosecond Pulses

    DEFF Research Database (Denmark)

    Turchinovich, Dmitry

    2008-01-01

    We demonstrate a monolithic, i.e. without any free-space coupling, all-single-mode passively modelocked Yb-fiber laser, with direct fiber-end delivery of 364−405 fs pulses of 4 nJ pulse energy using a low-loss hollow-core photonic crystal fiber compression.......We demonstrate a monolithic, i.e. without any free-space coupling, all-single-mode passively modelocked Yb-fiber laser, with direct fiber-end delivery of 364−405 fs pulses of 4 nJ pulse energy using a low-loss hollow-core photonic crystal fiber compression....

  15. 32-core Dense SDM Unidirectional Transmission of PDM-16QAM Signals Over 1600 km Using Crosstalk-managed Single-mode Heterogeneous Multicore Transmission Line

    DEFF Research Database (Denmark)

    Mizuno, Takayuki; Shibahara, K.; Ono, Hirotaka

    2016-01-01

    We demonstrate 32-core dense space-division multiplexed (DSDM) unidirectional transmission of PDM-16QAM 20-WDM signals over 1644.8 km employing a low-crosstalk single-mode heterogeneous 32-core fiber in a partial recirculating-loop system.......We demonstrate 32-core dense space-division multiplexed (DSDM) unidirectional transmission of PDM-16QAM 20-WDM signals over 1644.8 km employing a low-crosstalk single-mode heterogeneous 32-core fiber in a partial recirculating-loop system....

  16. Single mode solid state distributed feedback dye laser fabricated by grey scale electron beam lithography on dye doped SU-8 resist

    DEFF Research Database (Denmark)

    Balslev, Søren; Rasmussen, Torben; Shi, Peixiong

    2005-01-01

    are optically pumped at 532 nm, and exhibit low lasing threshold from 530 nJ/mm2 and single mode output at selectable wavelengths from 580 to 630 nm, determined by the grating pitch. The lasers are well suited for integration into polymer based lab-on-chip circuits for interference based sensing.......We demonstrate grey scale electron beam lithography on functionalized SU-8 resist for fabrication of single mode solid state dye laser devices. The resist is doped with Rhodamine 6G perchlorate and the lasers are based on a first order Bragg grating distributed feedback resonator. The lasers...

  17. Formation and conversion of defect centers in low water peak single mode optical fiber induced by gamma rays irradiation

    International Nuclear Information System (INIS)

    Wen, J. X.; Luo, W. Y.; Xiao, Z. Y.; Wang, T. Y.; Chen, Z. Y.; Zeng, X. L.

    2010-01-01

    The formation and conversion processes of defect centers in low water peak single mode optical (LWPSM) fiber irradiated with gamma rays were investigated at room temperature using electron spin resonance. Germanium electron center (GEC) and self-trapped hole center (STH) occur when the fibers are irradiated with 1 and 5 kGy cumulative doses, respectively. With the increase in irradiation doses, the GEC defect centers disappear, and new defect centers such as E ' centers (Si and Ge) and nonbridge oxygen hole centers (NBOHCs) generate. The generation of GEC and STH is attributed to the electron transfer, which is completely balanced. This is the main reason that radiation-induced attenuation (RIA) of the LWPSM fiber is only 10 dB/km at communication window. The new defect centers come from the conversion of GEC and STH to E ' centers and NBOHC, and the conversion processes cause bond cleavage, which is the root cause that the RIA of the LWPSM fiber significantly increases up to 180 dB/km at working window. Furthermore, the concentration of new defect centers is saturated easily even by increasing cumulative doses.

  18. Modeling satellite-Earth quantum channel downlinks with adaptive-optics coupling to single-mode fibers

    Science.gov (United States)

    Gruneisen, Mark T.; Flanagan, Michael B.; Sickmiller, Brett A.

    2017-12-01

    The efficient coupling of photons from a free-space quantum channel into a single-mode optical fiber (SMF) has important implications for quantum network concepts involving SMF interfaces to quantum detectors, atomic systems, integrated photonics, and direct coupling to a fiber network. Propagation through atmospheric turbulence, however, leads to wavefront errors that degrade mode matching with SMFs. In a free-space quantum channel, this leads to photon losses in proportion to the severity of the aberration. This is particularly problematic for satellite-Earth quantum channels, where atmospheric turbulence can lead to significant wavefront errors. This report considers propagation from low-Earth orbit to a terrestrial ground station and evaluates the efficiency with which photons couple either through a circular field stop or into an SMF situated in the focal plane of the optical receiver. The effects of atmospheric turbulence on the quantum channel are calculated numerically and quantified through the quantum bit error rate and secure key generation rates in a decoy-state BB84 protocol. Numerical simulations include the statistical nature of Kolmogorov turbulence, sky radiance, and an adaptive-optics system under closed-loop control.

  19. The Usability Analysis of Different Standard Single-Mode Optical Fibers and Its Installation Methods for the Interferometric Measurements

    Directory of Open Access Journals (Sweden)

    Jakub Cubik

    2013-01-01

    Full Text Available With optical fibers we are able to measure a variety of physical quantities. Optical fiber sensors sensitive to the change of the light phase, so-called interferometers referred in this article are one of the most sensitive sensors. Because we are able to detect phase changes with extreme precision, these sensors are thus suitable for demanding applications, where cost is not the main requirement. We have used the Mach-Zehnder configuration. The paper deals with the usage of different types of standard single-mode optical fibers in the civil engineering as an integrated acoustic sensor. Further experiments are focused on the different types of fiber installation methods, such as placement in the mounting foam, into the polystyrene or attachment onto the wooden surface and their effect on the measurements. Through the repeated measurements of harmonic frequencies were obtained information about the usable frequency range and sensitivity of the particular arrangement. Measurement was performed for both cases, where the specific type of fiber or specifically installed fiber was used as the measurement or as the reference. The final evaluation is based both on the experience gained during measurements and also using the statistical calculations.

  20. Microwave-assisted combustion synthesis of NiAl intermetallics in a single mode applicator: Modeling and optimisation

    International Nuclear Information System (INIS)

    Poli, G.; Sola, R.; Veronesi, P.

    2006-01-01

    The microwave-assisted combustion synthesis of NiAl intermetallics in a single mode applicator has been simulated numerically and performed with the aim of achieving the highest yields, energy efficiency and process reproducibility. The electromagnetic field modeling of the microwave system allowed to chose the proper experimental set-up and the materials more suitable for the application, minimising the reflected power and the risks of arcing. In all the experimental conditions tested, conversions of 3-5 g 1:1 atomic ratio Ni and Al powder compacts into NiAl ranged from 98.7% to 100%, requiring from 30 to 180 s with power from 500 to 1500 W. The optimisation procedure allowed to determine and quantify the effects of the main process variables on the ignition time, the NiAl yields and the specific energy consumption, leading to a fast, reproducible and cost-effective process of microwave-assisted combustion synthesis of NiAl intermetallics

  1. Fiber refractive index sensor based on dual polarized Mach-Zehnder interference caused by a single-mode fiber loop.

    Science.gov (United States)

    Chen, Lei; Zhang, Wei-Gang; Wang, Li; Zhou, Quan; Sieg, Jonathan; Zhao, De-Long; Wang, Biao; Yan, Tie-Yi; Wang, Song

    2016-01-01

    A novel refractive index (RI) sensor head is proposed and experimentally demonstrated in this paper. The proposed sensor head is composed of a segment of bared single-mode fiber and a fiber holder that is fabricated by a 3D printer. The mechanism of the sensor head is based on dual polarized Mach-Zehnder interference. According to the aforementioned mechanism, we derived that the RI responses of the resonance dips possess an exponential functional manner when the E field is along the fast or slow axes. In addition, based on the finite element method, we found that the resonance dips wavelength responses are more sensitive when the input E field is along the fast axis. A confirmation experiment was performed, and the results confirmed our hypothesis. The maximum arithmetic mean value of RI response is about 657.895  nm/RIU for the proposed sensor head when the ambient RI changes from 1.3350 to 1.4110. Moreover, in the case of the proposed liquid RI sensor head, aligning the E field along the fast axis is the potentially needed condition for polarization.

  2. Biologically inspired flexible quasi-single-mode random laser: An integration of Pieris canidia butterfly wing and semiconductors

    Science.gov (United States)

    Wang, Cih-Su; Chang, Tsung-Yuan; Lin, Tai-Yuan; Chen, Yang-Fang

    2014-10-01

    Quasi-periodic structures of natural biomaterial membranes have great potentials to serve as resonance cavities to generate ecological friendly optoelectronic devices with low cost. To achieve the first attempt for the illustration of the underlying principle, the Pieris canidia butterfly wing was embedded with ZnO nanoparticles. Quite interestingly, it is found that the bio-inspired quasi-single-mode random laser can be achieved by the assistance of the skeleton of the membrane, in which ZnO nanoparticles act as emitting gain media. Such unique characteristics can be interpreted well by the Fabry-Perot resonance existing in the window-like quasi-periodic structure of butterfly wing. Due to the inherently promising flexibility of butterfly wing membrane, the laser action can still be maintained during the bending process. Our demonstrated approach not only indicates that the natural biological structures can provide effective scattering feedbacks but also pave a new avenue towards designing bio-controlled photonic devices.

  3. Electro-opto-mechanical radio-frequency oscillator driven by guided acoustic waves in standard single-mode fiber

    Directory of Open Access Journals (Sweden)

    Yosef London

    2017-04-01

    Full Text Available An opto-electronic radio-frequency oscillator that is based on forward scattering by the guided acoustic modes of a standard single-mode optical fiber is proposed and demonstrated. An optical pump wave is used to stimulate narrowband, resonant guided acoustic modes, which introduce phase modulation to a co-propagating optical probe wave. The phase modulation is converted to an intensity signal at the output of a Sagnac interferometer loop. The intensity waveform is detected, amplified, and driven back to modulate the optical pump. Oscillations are achieved at a frequency of 319 MHz, which matches the resonance of the acoustic mode that provides the largest phase modulation of the probe wave. Oscillations at the frequencies of competing acoustic modes are suppressed by at least 40 dB. The linewidth of the acoustic resonance is sufficiently narrow to provide oscillations at a single longitudinal mode of the hybrid cavity. Competing longitudinal modes are suppressed by at least 38 dB as well. Unlike other opto-electronic oscillators, no radio-frequency filtering is required within the hybrid cavity. The frequency of oscillations is entirely determined by the fiber opto-mechanics.

  4. Adaptable Optical Fiber Displacement-Curvature Sensor Based on a Modal Michelson Interferometer with a Tapered Single Mode Fiber.

    Science.gov (United States)

    Salceda-Delgado, G; Martinez-Rios, A; Selvas-Aguilar, R; Álvarez-Tamayo, R I; Castillo-Guzman, A; Ibarra-Escamilla, B; Durán-Ramírez, V M; Enriquez-Gomez, L F

    2017-06-02

    A compact, highly sensitive optical fiber displacement and curvature radius sensor is presented. The device consists of an adiabatic bi-conical fused fiber taper spliced to a single-mode fiber (SMF) segment with a flat face end. The bi-conical taper structure acts as a modal coupling device between core and cladding modes for the SMF segment. When the bi-conical taper is bent by an axial displacement, the symmetrical bi-conical shape of the tapered structure is stressed, causing a change in the refractive index profile which becomes asymmetric. As a result, the taper adiabaticity is lost, and interference between modes appears. As the bending increases, a small change in the fringe visibility and a wavelength shift on the periodical reflection spectrum of the in-fiber interferometer is produced. The displacement sensitivity and the spectral periodicity of the device can be adjusted by the proper selection of the SMF length. Sensitivities from around 1.93 to 3.4 nm/mm were obtained for SMF length between 7.5 and 12.5 cm. Both sensor interrogations, wavelength shift and visibility contrast, can be used to measure displacement and curvature radius magnitudes.

  5. Effects of the gamma-ray irradiation on the optical absorption of pure silica core single-mode fibres in the visible and NIR range

    International Nuclear Information System (INIS)

    Calderon, A.; Calvo, E.; Figueroa, C.F.; Martinez-Rivero, C.; Matorras, F.; Rodrigo, T.; Sobron, M.; Vila, I.; Virto, A.L.; Arce, P.; Barcala, J.M.; Ferrando, A.; Josa, M.I.; Luque, J.M.; Molinero, A.; Navarrete, J.; Oller, J.C.; Yuste, C.

    2005-01-01

    Optical absorption induced by photon radiation was evaluated for several commercial pure silica core, single mode, optical fibres. The study was performed for three different wavelengths: 630, 670 and 785 nm. We have identified a fibre whose induced transmission loss stays below 1 dB/m after 300 kGy gamma-ray irradiation

  6. FAVORING PARTIES BY GENERAL LINEAR DIVISOR METHOD

    Directory of Open Access Journals (Sweden)

    Ion BOLUN

    2016-03-01

    Full Text Available Aspects of General Linear Divisor (GLDmethod favoring of parties, when distributing seats, are investigated. They are identified predisposing conditions of a particular party to favor parties and also the fact that predisposition of favoring smaller parties is increasing, and of favoring of larger parties is decreasing with the increase of constant c value. The condition of Hamilton equilibrium between two parties is defined and special cases of Hamilton equilibriumand quasi-equilibrium are described. Are identified areas of GLD method favoring of larger and of smaller parties depending on the number of parties and on values of constant c and ΔM. Onaverage, GLD method favors large parties at c 2 and did not favor any party at c = 2.

  7. Effects of γ and neutron irradiation on the optical absorption of pure silica core single-mode optical fibres from Nufern

    International Nuclear Information System (INIS)

    Calderon, A.; Martinez-Rivero, C.; Matorras, F.; Rodrigo, T.; Sobron, M.; Vila, I.; Virto, A.L.; Alberdi, J.; Arce, P.; Barcala, J.M.; Calvo, E.; Ferrando, A.; Josa, M.I.; Luque, J.M.; Molinero, A.; Navarrete, J.; Oller, J.C.; Valdivieso, P.; Yuste, C.; Fenyvesi, A.; Molnar, J.

    2006-01-01

    A measurement of the optical absorption, induced by photon irradiation up to a dose of 0.9 MGy, in Nufern silica core single-mode optical fibres is presented. In addition, the fibres were irradiated with neutrons, up to a total fluence of 2x10 14 cm -2 and the induced optical absorption was evaluated for four different wavelengths: 630, 670, 681 and 785 nm

  8. 22 CFR 1203.735-202 - Gifts, entertainment, and favors.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 2 2010-04-01 2010-04-01 true Gifts, entertainment, and favors. 1203.735-202 Section 1203.735-202 Foreign Relations UNITED STATES INTERNATIONAL DEVELOPMENT COOPERATION AGENCY EMPLOYEE..., contractual or other business or financial relations with the employee's agency; (2) Conducts operations or...

  9. Propagation of Single-Mode Fibre Laser Beams through an Optical ABCD System with Circular Aperture at the Fibre Output End

    International Nuclear Information System (INIS)

    Kai-Liang, Duan; Jian-Feng, Li; Wei, Zhao; Yi-Shan, Wang

    2008-01-01

    Based on the expansion expression of the fundamental mode of a single-mode fibre in terms of Laguerre–Gauss modes, the propagation of a beam of a weakly guiding fibre laser through an optical ABCD system with a circular aperture at the fibre end is studied. The results show that there is much difference between the propagation of the laser beam described by the expansion expression and by the Gaussian mode approximation. The depth of focus of the laser beam is longer than that of the Gaussian modes

  10. The Application of the Theory of Synthesis of a Delay Line with a Surface Acoustic Wave for a Single-Mode Oscillator of Electric Signals in Some Sensors of Non-Electrical Quantities

    Directory of Open Access Journals (Sweden)

    Šimko Milan

    2017-09-01

    Full Text Available The paper deals with the issue of constructing delay lines on the basis of surface acoustic waves and their application to single-mode oscillators. As a result of a theoretical analysis concrete delay lines are proposed.

  11. Single-Mode, High Repetition Rate, Compact Ho:YLF Laser for Space-Borne Lidar Applications

    Science.gov (United States)

    Bai, Yingxin; Yu, Jirong; Wong, Teh-Hwa; Chen, Songsheng; Petros, Mulugeta; Singh, Upendra N.

    2014-01-01

    A single transverse/longitudinal mode, compact Q-switched Ho:YLF laser has been designed and demonstrated for space-borne lidar applications. The pulse energy is between 34-40 mJ for 100-200 Hz operation. The corresponding peak power is >1 MW.

  12. Novel mid-infrared imaging system based on single-mode quantum cascade laser illumination and upconversion

    DEFF Research Database (Denmark)

    Tomko, Jan; Junaid, Saher; Tidemand-Lichtenberg, Peter

    2017-01-01

    Compared to the visible or near-infrared (NIR) spectral regions, there is a lack of very high sensitivity detectors in the mid-infrared (MIR) that operate near room temperature. Upconversion of the MIR light to NIR light that is imaged using affordable, fast, and sensitive NIR detectors or camera...

  13. A single source microwave photonic filter using a novel single-mode fiber to multimode fiber coupling technique.

    Science.gov (United States)

    Chang, John; Fok, Mable P; Meister, James; Prucnal, Paul R

    2013-03-11

    In this paper we present a fully tunable and reconfigurable single-laser multi-tap microwave photonic FIR filter that utilizes a special SM-to-MM combiner to sum the taps. The filter requires only a single laser source for all the taps and a passive component, a SM-to-MM combiner, for incoherent summing of signal. The SM-to-MM combiner does not produce optical interference during signal merging and is phase-insensitive. We experimentally demonstrate an eight-tap filter with both positive and negative programmable coefficients with excellent correspondence between predicted and measured values. The magnitude response shows a clean and accurate function across the entire bandwidth, and proves successful operation of the FIR filter using a SM-to-MM combiner.

  14. VCSEL Transmission at 10 Gb/s for 20 km Single Mode Fiber WDM-PON without Dispersion Compensation or Injection Locking

    DEFF Research Database (Denmark)

    Gibbon, Timothy Braidwood; Prince, Kamau; Pham, Tien Thang

    2011-01-01

    how off-center wavelength filtering of the VCSEL spectrum at an array waveguide grating can be used to mitigate the effect of chirp and the dispersion penalty. Transmission at 10Gb/s VCSEL over 23.6 km of single mode fiber is experimentally demonstrated, with a dispersion penalty of only 2.9 d......B. Simulated results are also presented which show that off-center wavelength filtering can extend the 10 Gb/s network reach from 11.7 km to 25.8 km for a 4 dB dispersion penalty. This allows for cheap and simple dispersion mitigation in next generation VCSEL based optical access networks....

  15. Differential modal delay measurements in a graded-index multimode fibre waveguide, using a single-mode fibre pro mode selection

    International Nuclear Information System (INIS)

    Sunak, H.R.D.; Soares, S.M.

    1981-01-01

    Differential model delay (DMD) measurements in graded-index multimode optical fibre waveguides, which are very promising for many types of communication system were carried out. These DMD measurements give a direct indication of the deviation of the refractive index profile, from the optimum value, at a given wavelength. For the first time, by using a single-mode fibre, a few guided modes in the graded-index fibre were selected, in two different ways: launching a few modes at the input end or selecting a few modes at the output end. By doing so important features of propagation in the fibre were revealed, especially the intermodal coupling that may exist. The importance of this determination of intermodal coupling or mode mixing, particularly when many fibres are joined together in a link, and the merits of DMD measurements in general and their importance for the production of high bandwidth graded-index fibres are discussed. (Author) [pt

  16. Optimization of a DPP-BOTDA sensor with 25 cm spatial resolution over 60 km standard single-mode fiber using Simplex codes and optical pre-amplification.

    Science.gov (United States)

    Soto, Marcelo A; Taki, Mohammad; Bolognini, Gabriele; Di Pasquale, Fabrizio

    2012-03-26

    Sub-meter distributed optical fiber sensing based on Brillouin optical time-domain analysis with differential pulse-width pairs (DPP-BOTDA) is combined with the use of optical pre-amplification and pulse coding. In order to provide significant measurement SNR enhancement and to avoid distortions in the Brillouin gain spectrum due to acoustic-wave pre-excitation, the pulse width and duty cycle of Simplex coding based on return-to-zero pulses are optimized through simulations. In addition, the use of linear optical pre-amplification increases the receiver sensitivity and the overall dynamic range of DPP-BOTDA measurements. Experimental results demonstrate for first time a spatial resolution of ~25 cm over a 60 km standard single-mode fiber (equivalent to ~240 k discrete sensing points) with temperature resolution of 1.2°C and strain resolution of 24 με.

  17. Transverse UV-laser irradiation-induced defects and absorption in a single-mode erbium-doped optical fiber

    International Nuclear Information System (INIS)

    Tortech, B.; Ouerdane, Y.; Boukenter, A.; Meunier, J. P.; Girard, S.; Van Uffelen, M.; Berghmans, F.; Regnier, E.; Berghmans, F.; Thienpont, H.

    2009-01-01

    Near UV-visible absorption coefficients of an erbium-doped optical fiber were investigated through an original technique based on a transverse cw UV-laser irradiation operating at 244 nm. Such irradiation leads to the generation of a quite intense guided luminescence signal in near UV spectral range. This photoluminescence probe source combined with a longitudinal translation of the fiber sample (at a constant velocity) along the UV-laser irradiation, presents several major advantages: (i) we bypass and avoid the procedures classically used to study the radiation induced attenuation which are not adapted to our case mainly because the samples present a very strong absorption with significant difficulties due to the injection of adequate UV-light levels in a small fiber diameter: (ii) the influence of the laser irradiation on the host matrix of the optical fiber is directly correlated to the evolution of the generated photoluminescence signal and (iii) in our experimental conditions, short fiber sample lengths (typically 20-30 cm) suffice to determine the associated absorption coefficients over the entire studied spectral domain. The generated photoluminescence signal is also used to characterize the absorption of the erbium ions in the same wavelength range with no cut-back method needed. (authors)

  18. Fabrication of sucrose biosensor based on single mode planar optical waveguide using co-immobilized plant invertase and GOD.

    Science.gov (United States)

    Bagal, Dipali S; Vijayan, Anu; Aiyer, R C; Karekar, R N; Karve, M S

    2007-06-15

    In present studies, the new optical sensing platform based on optical planar waveguide (OPWG) for sucrose estimation was reported. An evanescent-wave biosensor was designed by using novel agarose-guar gum (AG) biopolymer composite sol-gel with entrapped enzymes (acid invertase (INV) and glucose oxidase (GOD)). Partially purified watermelon invertase isolated from Citrullus vulgaris fruit (specific activity 832 units mg(-1)) in combination with GOD was physically entrapped in AG sol-gel and cladded on the surface of optical planar waveguide. Na(+)-K(+) ion-exchanged glass optical waveguides were prepared and employed for the fabrication of sucrose biosensor. By addressing the enzyme modified waveguide structure with, the optogeometric properties of adsorbed enzyme layer (12 microm) at the sensor solid-liquid interface were studied. The OPWG sensor with short response time (110 s) was characterized using the 0.2M acetate buffer, pH 5.5. The fabricated sucrose sensor showed concentration dependent linear response in the range 1 x 10(-10) to 1 x 10(-6)M of sucrose. Lower limit of detection of this novel AG-INV-GOD cladded OPWG sensor was found to be 2.5 x 10(-11)M sucrose, which indicates that the developed biosensor has higher sensitivity towards sucrose as compared to earlier reported sensors using various transducer systems. Biochips when stored at room temperature, showed high stability for 81 days with 80% retention of original sensitivity. These sucrose sensing biochips showed good operational efficiency for 10 cycles. The proper confinement of acid invertase and glucose oxidase in hydrogel composite was confirmed by scanning electron microscopy (SEM) images. The constructed OPWG sensor is versatile, easy to fabricate and can be used for sucrose measurements with very high sensitivity.

  19. When and why are reliable organizations favored?

    DEFF Research Database (Denmark)

    Ethiraj, Sendil; Yi, Sangyoon

    of the ensuing work examined only corollary implications of this observation. We treat the observation as a research question and ask: when and why are reliable organizations favored by evolutionary forces? Using a simple theoretical model, we direct attention at a minimal set of variables that are implicated...... a representation of reality. Thus, our attempt is best characterized as shining a spotlight on a small part of the larger canvas that constitutes the literature on organizational change....

  20. Coupling Characteristics of Fused Optical Fiber Coupler Formed with Single-Mode Fiber and Photonic Crystal Fiber Having Air Hole Collapsed Taper

    Directory of Open Access Journals (Sweden)

    Hirohisa Yokota

    2016-01-01

    Full Text Available Fused coupler forming with a single-mode fiber (SMF and a photonic crystal fiber (PCF is one of the solutions for optical coupling from a light source to a PCF. In this paper, we presented coupling characteristics of a fused fiber coupler formed with an ordinary SMF and a PCF having air hole collapsed taper. A prototype of SMF-PCF coupler with air hole collapsed taper was fabricated using CO2 laser irradiation. The coupling efficiency from SMF to PCF was −6.2 dB at 1554 nm wavelength in the fabricated coupler. The structure of the SMF-PCF coupler to obtain high coupling efficiency was theoretically clarified by beam propagation analysis using an equivalent model of the coupler with simplification. It was clarified that appropriately choosing the prestretched or etched SMF diameter and the length of air hole collapsed region was effective to obtain high coupling efficiency that was a result of high extinction ratio at cross port and low excess loss. We also demonstrated that the diameter of prestretched SMF to obtain high coupling efficiency was insensitive to the air hole diameter ratio to pitch of the PCF in the air hole collapsed SMF-PCF coupler.

  1. Analysis of Signal-to-Crosstalk Ratio Variations due to Four-Wave Mixing in Dense Wavelength Division Multiplexing Systems Implemented with Standard Single-Mode Fibers

    Directory of Open Access Journals (Sweden)

    Sait Eser KARLIK

    2016-10-01

    Full Text Available In this paper, variation of the signal-to-crosstalk ratio (SXR due to effects of four-wave mixing (FWM has been analyzed on center channels of 5-, 7-, 9-channel dense wavelength division multiplexing (DWDM systems implemented with G.652 standard single-mode fibers (SSMFs for 12.5 GHz, 25 GHz, 50 GHz and 100 GHz equal channel spacing values. Center channels on such systems are the most severely impacted channels by FWM. Therefore, results obtained are the worst-case values for the DWDM system performance and important for system design. Simulations have been performed for systems using three different commercially available SMFs having different design parameter values for chromatic dispersion, dispersion slope, nonlinearity coefficient and attenuation coefficient which are all in the scope of the G.652 Recommendation of Telecommunication Standardization Sector of International Telecommunication Union (ITU-T for SSMFs. In those simulations, under the impact of FWM, variation of SXR with variations in input powers, channel spacings and link lengths have been observed. Simulation results display the combined effect of the optical fiber and system design parameters on FWM performance of DWDM systems and give important clues for not only long-haul but also access network implementations of DWDM systems.

  2. Quantum dynamics of a BEC interacting with a single-mode quantized field under the influence of a dissipation process: thermal and squeezed vacuum reservoirs

    Science.gov (United States)

    Ghasemian, E.; Tavassoly, M. K.

    2017-09-01

    In this paper we consider a system consisting of a number of two-level atoms in a Bose-Einstein condensate (BEC) and a single-mode quantized field, which interact with each other in the presence of two different damping sources, i.e. cavity and atomic reservoirs. The reservoirs which we consider here are thermal and squeezed vacuum ones corresponding to field and atom modes. Strictly speaking, by considering both types of reservoirs for each of the atom and field modes, we investigate the quantum dynamics of the interacting bosons in the system. Then, via solving the quantum Langevin equations for such a dissipative BEC system, we obtain analytical expressions for the time dependence of atomic population inversion, mean atom as well as photon number and quadrature squeezing in the field and atom modes. Our investigations demonstrate that for modeling the real physical systems, considering the dissipation effects is essential. Also, numerical calculations which are presented show that the atomic population inversion, the mean number of atoms in the BEC and the photons in the cavity possess damped oscillatory behavior due to the presence of reservoirs. In addition, non-classical squeezing effects in the field quadrature can be observed especially when squeezed vacuum reservoirs are taken into account. As an outstanding property of this model, we may refer to the fact that one can extract the atom-field coupling constant from the frequency of oscillations in the mentioned quantities such as atomic population inversion.

  3. Opto-mechanical design of a buckling cavity in a novel high-performance outside-plant robust field installable single-mode fibre connector

    Science.gov (United States)

    Ebraert, Evert; Van Erps, Jürgen; Beri, Stefano; Watté, Jan; Thienpont, Hugo

    2014-05-01

    Fibre-to-the-home (FTTH) networks provide an ideal means to reach the goal the European Union has set to provide 50 % of the households with a broadband connection faster than 100 Mb/s. Deployment of FTTH networks, which is still costly today, could be significantly boosted by novel ferrule-less connectors which don't require highly skilled personnel and allow installation in the field. We propose a ferrule-less connector in which two single-mode fibres (SMFs) are aligned and maintain physical contact by ensuring that at least one fibre is in a buckled state. To this end, we design a cavity in which a fibre can buckle in a controlled way. Using finite element analysis simulations to investigate the shape of the formed buckle for various buckling cavity lengths, we show that it can be accurately approximated by a cosine function. In addition, the optical performance of a buckled SMF is investigated by bending loss calculations and simulations. We show a good agreement between the analytical and the simulated bending loss results for a G.652 fibre at a wavelength of 1550 nm. Buckling cavity lengths smaller than 20 mm should be avoided to keep the optical bending loss due to buckling below 0.1 dB. In this case the cavity height should at least be 2 mm to avoid mechanical confinement of the fibre.

  4. Misalignment Consideration in Laser Diode to Circular Core Single-Mode Dispersion-Shifted/Dispersion-Flattened Fiber Excitation via Hemispherical Microlens on the Tip of the Fiber

    Science.gov (United States)

    Kamila, Kiranmay; Middya, Tapas Ranjan; Gangopadhyay, Sankar

    2016-06-01

    We report the theoretical study of excitation efficiency in the presence of possible transverse and angular misalignments in the case of excitation of single-mode circular core dispersion-shifted and dispersion-flattened fiber by laser diode via hemispherical microlens on the tip of the fiber. The present study takes into consideration limited aperture allowed by the hemispherical microlens. Employing ABCD matrix technique involving refraction of paraxial rays by a hemispherical microlens on the fiber tip, we formulate analytical expressions for the coupling efficiencies in the presence of the said misalignments. The estimations of the concerned efficiencies as well as associated losses by using our formulations will require little computations. But the results found are sufficiently accurate and the execution of our formalism is simple. Thus the prescribed analytical expressions are useful and new in the sense that prediction of coupling optics can be made accurately but in a simple manner without requiring lengthy numerical integrations concerned with conventional phase model technique. Moreover, the present study, as per our knowledge till date, being the first theoretical investigation of excitation efficiency for the said type of coupling device, will benefit the experimentalists, designers and packagers who are working in the field of optimum launch optics involving such coupler.

  5. Assessment of magneto-optic Faraday effect-based drift on interferometric single-mode fiber optic gyroscope (IFOG) as a function of variable degree of polarization (DOP)

    International Nuclear Information System (INIS)

    Çelikel, Oğuz; Sametoğlu, Ferhat

    2012-01-01

    In this study, a novel interferometric fiber optic gyroscope (IFOG), which has a different depolarizer structure, is designed in TUBITAK UME (National Metrology Institute of Turkey) to experimentally and relatively evaluate the effect of the degree of polarization on the Faraday effect-based drift of the light waves injected into both arms of a Sagnac interferometer. In order to observe whether or not any change occurs in the Faraday-based drift, depending on the variations in degree of polarization (DOP), a triple structure-depolarizer IFOG possessing adjustable DOP is firstly designed and prototyped. The minimum DOP achieved with triple structure-depolarizers is typically 0.15% for both clockwise (CW) and counterclockwise (CCW) light waves at both arms of the Sagnac interferometer. The experimental evaluations about the drift are given for DOP changes extending from 78.00% to 0.15% together with two main and different theoretical approaches in the literature. According to the experimental evaluations given herein, it is experimentally proved that the Faraday-based drift does not change depending on DOP values of both CW and CCW light waves injected into the single-mode (SM) sensing coil and it is impossible to state a concept of a depolarized IFOG by considering the polarization state at the entrance arms of the SM sensing coil. (paper)

  6. Scanner deflection of top-hat converted single-mode lasers for cost-effective micro-machining at highest quality

    Science.gov (United States)

    Guetlich, B.; Mitra, T.; Toennissen, F.; Homburg, O.; Aschke, L.

    2009-02-01

    Direct laser patterning of various materials is today widely used in several micro-system production lines like inkjet printing, solar cell technology, flat-panel display production and medicine. Typically single-mode solid state lasers and their higher harmonics are used especially for machining of holes and grooves. The most prominent lasers are pulsed Nd:YAG lasers and their harmonics @ 266, 355 and 532 nm. Recently, the striking advantages of flat top intensity distributions for the efficiency and quality of these processes were demonstrated. The use of LIMO's compact Gaussian-to- top-hat converter enables the creation of steeper and sharper edges. Additionally, the higher energy efficiency of rectangular top hat profiles compared to smooth, circular Gaussian shapes allows for faster patterning. A standard method to reduce process times is the use of optical scanning systems. Yet, the application of Gaussian-to-top-hat converters in combination with a scanner was hindered by distortions of the top hat introduced by the F-Theta focussing lens of the scanners even at very small deflection angles (solar panels.

  7. Saturated evanescent-wave absorption of few-layer graphene-covered side-polished single-mode fiber for all-optical switching

    Science.gov (United States)

    Peng, Kaung-Jay; Wu, Chun-Lung; Lin, Yung-Hsiang; Wang, Hwai-Yung; Cheng, Chih-Hsien; Chi, Yu-Chieh; Lin, Gong-Ru

    2018-01-01

    Using the evanescent-wave saturation effect of hydrogen-free low-temperature synthesized few-layer graphene covered on the cladding region of a side-polished single-mode fiber, a blue pump/infrared probe-based all-optical switch is demonstrated with specific wavelength-dependent probe modulation efficiency. Under the illumination of a blue laser diode at 405 nm, the few-layer graphene exhibits cross-gain modulation at different wavelengths covering the C- and L-bands. At a probe power of 0.5 mW, the L-band switching throughput power variant of 16 μW results in a probe modulation depth of 3.2%. Blue shifting the probe wavelength from 1580 to 1520 nm further enlarges the switching throughput power variant to 24 mW and enhances the probe modulation depth to 5%. Enlarging the probe power from 0.5 to 1 mW further enlarges the switching throughput power variant from 25 to 58 μW to promote its probe modulation depth of up to 5.8% at 1520 nm. In contrast, the probe modulation depth degrades from 5.1% to 1.2% as the pumping power reduces from 85 to 24 mW, which is attributed to the saturable absorption of the few-layer graphene-based evanescent-wave absorber. The modulation depth at wavelength of 1550 nm under a probe power of 1 mW increases from 1.2% to 5.1%, as more carriers can be excited when increasing the blue laser power from 24 to 85 mW, whereas it decreases from 5.1% to 3.3% by increasing the input probe power from 1 to 2 mW to show an easier saturated condition at longer wavelength.

  8. Appeals court reverses verdict favoring drug companies.

    Science.gov (United States)

    1995-06-02

    An appeals court reversed a verdict favoring drug companies after the widow of a hemophiliac, whose death was linked to HIV-tainted blood products, sued four pharmaceutical companies to pay damages. The four companies, Alpha Therapeutic Corp., Miles Laboratories Inc., Armour Pharmaceutical Co., and Baxter Travenol Laboratories Inc., provided Factor VIII, a clotting concentrate, to [name removed] [name removed], the plaintiff's husband, from 1972 until his death in 1987. [Name removed]'s wife sued the companies, alleging that the defendants negligently solicited blood plasma from paid donors who had a high risk of having HIV, failed to determine whether any lots of Factor VIII contained plasma from an at-risk donor, failed to warn consumers of possible risks, and failed to heat-treat HIV and other viruses in Factor VIII, despite industry-wide knowledge of the risk of infection. The three-judge panel said the trial judge's decision to avoid ruling on the antigenic stimulation theory, based on insufficient evidence, was improper. In addition, the appeals court said a retrial is necessary because of improper remarks made by Alpha's attorney.

  9. Children's need for favorable acoustics in schools

    Science.gov (United States)

    Nelson, Peggy B.

    2003-10-01

    Children continue to improve their understanding of speech in noise and reverberation throughout childhood and adolescence. They do not typically achieve adult performance levels until their late teenage years. As a result, schools that are designed to be acoustically adequate for adult understanding may be insufficient for full understanding by young children. In addition, children with hearing loss, those with attention problems, and those learning in a non-native language require even more favorable signal-to-noise ratios. This tutorial will review the literature gathered by the ANSl/ASA working group on classroom acoustics that shaped the recommendations of the working group. Special topics will include speech perception data from typically developing infants and children, from children with hearing loss, and from adults and children listening in a non-native language. In addition, the tutorial will overview recommendations contained within ANSI standard 12.60-2002: Acoustical Performance Criteria, Design Requirements, and Guidelines for Schools. The discussion will also include issues related to designing quiet classrooms and working with local schools and professionals.

  10. Great Basin geologic framework and uranium favorability

    International Nuclear Information System (INIS)

    Larson, L.T.; Beal, L.H.

    1978-01-01

    Work on this report has been done by a team of seven investigators assisted over the project span by twenty-three undergraduate and graduate students from May 18, 1976 to August 19, 1977. The report is presented in one volume of text, one volume or Folio of Maps, and two volumes of bibliography. The bibliography contains approximately 5300 references on geologic subjects pertinent to the search for uranium in the Great Basin. Volume I of the bibliography lists articles by author alphabetically and Volume II cross-indexes these articles by location and key word. Chapters I through IV of the Text volume and accompanying Folio Map Sets 1, 2, 3, 4, and 5, discuss the relationship of uranium to rock and structural environments which dominate the Great Basin. Chapter 5 and Map Sets 6 and 7 provide a geochemical association/metallogenic grouping of mineral occurrences in the Great Basin along with information on rock types hosting uranium. Chapter VI summarizes the results of a court house claim record search for 'new' claiming areas for uranium, and Chapter VII along with Folio Map Set 8 gives all published geochronological data available through April 1, 1977 on rocks of the Great Basin. Chapter VIII provides an introduction to a computer analysis of characteristics of certain major uranium deposits in crystalline rocks (worldwide) and is offered as a suggestion of what might be done with uranium in all geologic environments. We believe such analysis will assist materially in constructing exploration models. Chapter IX summarizes criteria used and conclusions reached as to the favorability of uranium environments which we believe to exist in the Great Basin and concludes with recommendations for both exploration and future research. A general summary conclusion is that there are several geologic environments within the Great Basin which have considerable potential and that few, if any, have been sufficiently tested

  11. 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...

  12. Fabrication Processes for Surface-Emitting via External 45-DEGREE Reflectors, High-Power via Arrayed Ridge - Single-Mode Phase-Locked Aluminum Gallium Arsenide/gallium Arsenide Semiconductor Laser Sources.

    Science.gov (United States)

    Porkolab, Gyorgy Arpad

    The fabrication of monolithically integrated configurations of semiconductor lasers incorporating multiple functions is still an open issue today in engineering. A useful set of functions to integrate are: surface-emitting, high -power, phase-locked, single-mode, and collimated laser beam output. In this work new materials and advanced fabrication processes are developed for integrating the first four of the five functions listed. The interest in semiconductor lasers is due to their greater than 90% internal quantum efficiency in converting current-flux to photon-flux, their small size and weight, and their wavelength range from 400 to 1,550 nm. Multitudes of applications are possible for semiconductor laser sources ranging from the low-volume market of satellite-based communications systems to the high-volume market of image display screens. Semimetallic amorphous carbon (SMAC) thin film is introduced as an etch mask for chemically assisted ion beam etching (CAIBE) resulting in smooth etched facets in AlGaAs/GaAs at normal- and 45-degrees- incidence angles. A self-aligned etch technique is introduced using 4 separate photoresist selector-masks on top of a fixed SMAC master -mask on top of the AlGaAs/GaAs substrate to perform 4 separate CAIBE etches at 3 different angles and to 3 different depths to create self-aligned 3-dimensional microstructures of 1.3-μm deep ridge waveguides (RWG), 6-μm deep laser facets, and 11- μm long back-to-back 45-degree reflectors arranged in 3 by 100 arrays. Trenches on topside and underside of laser facets are introduced to deflect current away from laser facets. Silicon-rich nitro-oxide thin film is introduced as triple-use encapsulation to provide chemical passivation of AlGaAs/GaAs, optical anti-reflection coating by being refractive-index matched to AlGaAs/GaAs, and electrical insulation. A pincer-action sample-holder for CAIBE is introduced allowing samples to heat up by ion beam heating. Various surface preparations

  13. Factors favorable to public participation success

    Energy Technology Data Exchange (ETDEWEB)

    Peelle, E.; Schweitzer, M.; Munro, J.; Carnes, S.; Wolfe, A.

    1996-05-01

    Categories of factors linked to successful public participation (PP) program outcomes include PP process, organizational context, sociopolitical context, strategic considerations and unique (special circumstances) factors. We re-order the long list factors according to how essential, important, and unique they are and discuss their significance and interrelationships. It is argued that bureacratic structure and operational modes are basically in conflict with features of successful PP programs (openness, two-way education, communication with nonexpert outsiders). If this is so, then it is not surprising that the factors essential for PP success in bureacracies involve extraordinary management efforts by agencies to bypass, compensate for, or overcome structural constraints. We conclude by speculating about the long-term viability of PP practices in the agency setting as well as the consequences for agencies that attempt the problematic task of introducing PP into their complex, mission-oriented organizations.

  14. Favorable results after total wrist arthroplasty

    DEFF Research Database (Denmark)

    Boeckstyns, Michel E. H.; Herzberg, G.; Merser, Søren

    2013-01-01

    survival was 0.9 at 5–9 years. Interpretation The clinical results in terms of pain, motion, strength, and function were similar to those in previous reports. The implant survival was 0.9 at 9 years, both in rheumatoid and non-rheumatoid cases, which is an important improvement compared to the earlier......Background and purpose During the past 40 years, several attempts have been made with total wrist arthroplasty to avoid fusion in severely destroyed wrists. The results have often been disappointing. There is only modest clinical documentation due to the small number of patients (especially non......-rheumatoid cases) and short follow-up times. Here we report a multicenter series using a third-generation implant with a minimum follow-up time of 5 years. Methods In 2012, data were retrieved from a registry of consecutive wrist operations at 7 centers with units specialized in hand surgery, between 2003 and 2007...

  15. Factors favorable to public participation success

    International Nuclear Information System (INIS)

    Peelle, E.; Schweitzer, M.; Munro, J.; Carnes, S.; Wolfe, A.

    1996-01-01

    Categories of factors linked to successful public participation (PP) program outcomes include PP process, organizational context, sociopolitical context, strategic considerations and unique (special circumstances) factors. We re-order the long list factors according to how essential, important, and unique they are and discuss their significance and interrelationships. It is argued that bureacratic structure and operational modes are basically in conflict with features of successful PP programs (openness, two-way education, communication with nonexpert outsiders). If this is so, then it is not surprising that the factors essential for PP success in bureacracies involve extraordinary management efforts by agencies to bypass, compensate for, or overcome structural constraints. We conclude by speculating about the long-term viability of PP practices in the agency setting as well as the consequences for agencies that attempt the problematic task of introducing PP into their complex, mission-oriented organizations

  16. 12 CFR 560.110 - Most favored lender usury preemption.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 5 2010-01-01 2010-01-01 false Most favored lender usury preemption. 560.110... INVESTMENT Lending and Investment Provisions Applicable to all Savings Associations § 560.110 Most favored... permits its most favored lender to charge late fees, then a savings association located in that state may...

  17. Identifying quantumness via addition-then-subtraction operation

    OpenAIRE

    Lee, Su-Yong; Noh, Changsuk; Kaszlikowski, Dagomir

    2012-01-01

    We propose a measure of quantumness based on an addition-then-subtraction operation. We demonstrate how this measure can distinguish between classical and bosonic particles by investigating in detail multi-particle bosonic systems. Experimental schemes implementing this measure for bosons in all-optical and atom-cavity systems are provided. We also apply this measure to single-mode fermionic systems.

  18. Damage, refractive index and near-field intensity profiles in a single-mode waveguide of LiNbO3 by 400 keV He ion implantation

    Science.gov (United States)

    Zhang, S. M.; Liu, X. H.; Qin, X. F.; Wang, K. M.; Liu, X.

    2010-11-01

    We report on a single-mode waveguide in lithium niobate produced by 400 keV He ion implantation with a dose of 3 × 1016 ions cm-2 at liquid nitrogen temperature. Rutherford backscattering/channelling spectra have been measured in the waveguide before and after annealing and the damage profile has been extracted. The shape of the measured damage profile is similar to that of the ordinary refractive index by the intensity calculation method. The near-field intensity profile in a ridge waveguide is given and the propagation loss for the extraordinary index is estimated to be 1.9 dB cm-1.

  19. Autoras africanas: A favor de las mujeres=African authors: In favor of women

    Directory of Open Access Journals (Sweden)

    Socorro Suárez Lafuente

    2017-06-01

    Full Text Available Resumen: La cultura occidental produce binomios de poder fuertemente inscritos en el lenguaje y el imaginario colectivo. Las subversiones aparecen primero en la zona dominante, como el feminismo, que se extiende, posteriormente, a otros feminismos, igualmente lógicos y reivindicativos, pero con menos capacidad de visibilización en un mundo globalizado. Las mujeres de grupos minorizados que han conseguido acceder a la educación han levantado sus voces y utilizado su potencial creativo a favor de las silenciadas de su cultura, a las que no alcanzaban el feminismo blanco occidental. Amma Darko, Bessie Head y Chimamanda Ngozi Adichie son algunos de los nombres que encabezan un movimiento africano feminista, que prioriza la libertad individual de las mujeres y les hace sentirse orgullosas de ser africanas.   Abstract Western culture produces binaries of power that are deeply inscribed both in language and in the collective imaginarium. Subversions tend to appear in the more affluent class, as is the case with feminism, which later extend to other feminisms, equally important and vindicatory, but with fewer opportunities to become visible within a globalized world. Many women from minoritized groups have had access to education, have been able to use their creative force and have become the voice of many silent women who were not included in the successive waves of Western feminisms. Amma Darko, Bessie Head and Chimamanda Ngozi Adichie are but a few names at the forefront of African feminism, a movement that fights for the individual rights of women and makes them feel proud of their Africanism.

  20. Hybrid III-V/SOI single-mode vertical-cavity laser with in-plane emission into a silicon waveguide

    DEFF Research Database (Denmark)

    Park, Gyeong Cheol; Xue, Weiqi; Semenova, Elizaveta

    2015-01-01

    We report a III-V-on-SOI vertical-cavity laser emitting into an in-plane Si waveguide fabricated by using CMOS-compatible processes. The fabricated laser operates at 1.54 µm with a SMSR of 33 dB and a low threshold.......We report a III-V-on-SOI vertical-cavity laser emitting into an in-plane Si waveguide fabricated by using CMOS-compatible processes. The fabricated laser operates at 1.54 µm with a SMSR of 33 dB and a low threshold....

  1. Narrow ridge waveguide high power single mode 1.3-μm InAs/InGaAs ten-layer quantum dot lasers

    Directory of Open Access Journals (Sweden)

    Cao Q

    2007-01-01

    Full Text Available AbstractTen-layer InAs/In0.15Ga0.85As quantum dot (QD laser structures have been grown using molecular beam epitaxy (MBE on GaAs (001 substrate. Using the pulsed anodic oxidation technique, narrow (2 μm ridge waveguide (RWG InAs QD lasers have been fabricated. Under continuous wave operation, the InAs QD laser (2 × 2,000 μm2 delivered total output power of up to 272.6 mW at 10 °C at 1.3 μm. Under pulsed operation, where the device heating is greatly minimized, the InAs QD laser (2 × 2,000 μm2 delivered extremely high output power (both facets of up to 1.22 W at 20 °C, at high external differential quantum efficiency of 96%. Far field pattern measurement of the 2-μm RWG InAs QD lasers showed single lateral mode operation.

  2. Favorability for uranium in tertiary sedimentary rocks, southwestern Montana

    International Nuclear Information System (INIS)

    Wopat, M.A.; Curry, W.E.; Robins, J.W.; Marjaniemi, D.K.

    1977-10-01

    Tertiary sedimentary rocks in the basins of southwestern Montana were studied to determine their favorability for potential uranium resources. Uranium in the Tertiary sedimentary rocks was probably derived from the Boulder batholith and from silicic volcanic material. The batholith contains numerous uranium occurrences and is the most favorable plutonic source for uranium in the study area. Subjective favorability categories of good, moderate, and poor, based on the number and type of favorable criteria present, were used to classify the rock sequences studied. Rocks judged to have good favorability for uranium deposits are (1) Eocene and Oligocene strata and undifferentiated Tertiary rocks in the western Three Forks basin and (2) Oligocene rocks in the Helena basin. Rocks having moderate favorability consist of (1) Eocene and Oligocene strata in the Jefferson River, Beaverhead River, and lower Ruby River basins, (2) Oligocene rocks in the Townsend and Clarkston basins, (3) Miocene and Pliocene rocks in the Upper Ruby River basin, and (4) all Tertiary sedimentary formations in the eastern Three Forks basin, and in the Grasshopper Creek, Horse Prairie, Medicine Lodge Creek, Big Sheep Creek, Deer Lodge, Big Hole River, and Bull Creek basins. The following have poor favorability: (1) the Beaverhead Conglomerate in the Red Rock and Centennial basins, (2) Eocene and Oligocene rocks in the Upper Ruby River basin, (3) Miocene and Pliocene rocks in the Townsend, Clarkston, Smith River, and Divide Creek basins, (4) Miocene through Pleistocene rocks in the Jefferson River, Beaverhead River, and Lower Ruby River basins, and (5) all Tertiary sedimentary rocks in the Boulder River, Sage Creek, Muddy Creek, Madison River, Flint Creek, Gold Creek, and Bitterroot basins

  3. Cordilleran metamorphic core complexes and their uranium favorability

    International Nuclear Information System (INIS)

    Coney, P.J.; Reynolds, S.J.

    1980-11-01

    The objective of this report is to provide a descriptive body of knowledge on Cordilleran metamorphic core complexes including their lithologic and structural characteristics, their distribution within the Cordillera, and their evolutionary history and tectonic setting. The occurrence of uranium in the context of possibility for uranium concentration is also examined. This volume contains appendices of the following: annotated bibliography of Cordilleran metamorphic core complexes; annotated bibliography of the uranium favorability of Cordilleran metamorphic core complexes; uranium occurrences in the Cordilleran metamorphic core complex belt; and geology, uranium favorability, uranium occurrences and tectonic maps of individual Cordilleran metamorphic core complexes; and locations, lithologic descriptions, petrographic information and analytical data for geochemical samples

  4. 11 CFR 7.8 - Gifts, entertainment, and favors.

    Science.gov (United States)

    2010-01-01

    ... affected by the performance or nonperformance of the Commissioner or employee's official duty. (b... Employees or Commissioners § 7.8 Gifts, entertainment, and favors. (a) A Commissioner or employee of the... persons concerned which are the motivating factors; (2) To the acceptance of food, refreshments, and...

  5. 22 CFR 1203.735-305 - Gifts, entertainment, and favors.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 2 2010-04-01 2010-04-01 true Gifts, entertainment, and favors. 1203.735-305 Section 1203.735-305 Foreign Relations UNITED STATES INTERNATIONAL DEVELOPMENT COOPERATION AGENCY EMPLOYEE RESPONSIBILITIES AND CONDUCT Ethical and Other Conduct and Responsibilities of Special Government Employees § 1203...

  6. Preschoolers Reduce Inequality While Favoring Individuals with More

    Science.gov (United States)

    Li, Vivian; Spitzer, Brian; Olson, Kristina R.

    2014-01-01

    Inequalities are everywhere, yet little is known about how children respond to people affected by inequalities. This article explores two responses--minimizing inequalities and favoring those who are advantaged by them. In Studies 1a (N = 37) and 1b (N = 38), 4- and 5-year-olds allocated a resource to a disadvantaged recipient, but judged…

  7. 18 CFR 706.202 - Gifts, entertainment, and favors.

    Science.gov (United States)

    2010-04-01

    ... 18 Conservation of Power and Water Resources 2 2010-04-01 2010-04-01 false Gifts, entertainment, and favors. 706.202 Section 706.202 Conservation of Power and Water Resources WATER RESOURCES COUNCIL... loans from banks or other financial institutions on customary terms to finance proper and usual...

  8. Learning acceleration for gifted students: Favorable and unfavorable arguments

    OpenAIRE

    Rodrigues Maia-Pinto, Renata; Souza Fleith, Denise de

    2012-01-01

    This paper analyzes acceleration in education as a practice for meeting the educational needs of gifted students, and points out favorable and unfavorable arguments on the use of this practice. Acceleration is an educational practice consisting of several teaching strategies designed to encourage academically gifted students and reduce their time spent in school. It promotes faster learning by matching the curriculum to the student’s level of knowledge, interest and motivation. There are seve...

  9. Menor valor: ¿oferta más favorable?

    Directory of Open Access Journals (Sweden)

    Iván Alirio Ramírez Rusinque

    2014-07-01

    Full Text Available La más importante transformación establecida por la Ley 1150 de 2007 en la contratación estatal radicó en la determinación del menor valor como la oferta más favorable para las entidades estatales, cuando se trate de la adquisición o suministro de bienes y servicios de características técnicas uniformes y de común utilización. Por ello, reviste de gran importancia realizar un análisis desde el punto de vista jurídico y normativo, que permita establecer si la mutación sufrida al concepto de oferta más favorable trajo consigo los fines perseguidos por la reforma, o en su defecto fue perjudicial la solución, al afectar el deber de selección objetiva, los principios de la contratación estatal de igualdad, eficacia, transparencia, planeación y equilibrio financiero del contrato y el principio constitucional de la libre competencia. Para de esta forma establecer si el modelo del menor valor como criterio de la oferta más favorable resulta eficiente jurídicamente en el campo de la contratación estatal, y si las reglas establecidas en la actualidad permiten el desarrollo armónico del sistema establecido por la Ley 1150 de 2007.

  10. More evidence in favor of light dark matter particles?

    International Nuclear Information System (INIS)

    Boehm, Celine; Ascasibar, Yago

    2004-01-01

    In a previous work, it was found that the light dark matter scenario could be a possible explanation to the 511 keV emission line detected at the center of our galaxy. Here, we show that hints of this scenario may also have been discovered in particle physics experiments. This could explain the discrepancy between the measurement of the fine structure constant and the value referenced in the CODATA. Finally, our results indicate that some of the light dark matter features could be tested in accelerators. Their discovery might favor N=2 supersymmetry

  11. Catalytically favorable surface patterns in Pt-Au nanoclusters

    KAUST Repository

    Mokkath, Junais Habeeb

    2013-01-01

    Motivated by recent experimental demonstrations of novel PtAu nanoparticles with highly enhanced catalytic properties, we present a systematic theoretical study that explores principal catalytic indicators as a function of the particle size and composition. We find that Pt electronic states in the vicinity of the Fermi level combined with a modified electron distribution in the nanoparticle due to Pt-to-Au charge transfer are the origin of the outstanding catalytic properties. From our model we deduce the catalytically favorable surface patterns that induce ensemble and ligand effects. © The Royal Society of Chemistry 2013.

  12. Donepezil regulates energy metabolism and favors bone mass accrual.

    Science.gov (United States)

    Eimar, Hazem; Alebrahim, Sharifa; Manickam, Garthiga; Al-Subaie, Ahmed; Abu-Nada, Lina; Murshed, Monzur; Tamimi, Faleh

    2016-03-01

    The autonomous nervous system regulates bone mass through the sympathetic and parasympathetic arms. The sympathetic nervous system (SNS) favors bone loss whereas the parasympathetic nervous system (PNS) promotes bone mass accrual. Donepezil, a central-acting cholinergic agonist, has been shown to down-regulate SNS and up-regulate PNS signaling tones. Accordingly, we hypothesize that the use of donepezil could have beneficial effects in regulating bone mass. To test our hypothesis, two groups of healthy female mice were treated either with donepezil or saline. Differences in body metabolism and bone mass of the treated groups were compared. Body and visceral fat weights as well as serum leptin level were increased in donepezil-treated mice compared to control, suggesting that donepezil effects on SNS influenced metabolic activity. Donepezil-treated mice had better bone quality than controls due to a decrease in osteoclasts number. These results indicate that donepezil is able to affect whole body energy metabolism and favors bone mass in young female WT mice. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Is there a relationship between patient satisfaction and favorable outcomes?

    Science.gov (United States)

    Kennedy, Gregory D; Tevis, Sarah E; Kent, K Craig

    2014-10-01

    Patient satisfaction with the health care experience has become a top priority for Centers for Medicare and Medicaid Services. With resources and efforts directed at patient satisfaction, we evaluated whether high patient satisfaction measured by HCAHPS (Hospital Consumer Assessment of Healthcare Providers and Systems) surveys correlates with favorable outcomes. Medical centers were identified from the University HealthSystem Consortium database from 2011 to 2012. Variables included hospital characteristics, process measure compliance, and surgical outcomes. Chi-squared analysis was used to evaluate for variables associated with high patient satisfaction (defined as hospitals that scored above the 50th percentile of top box scores). We identified 171 hospitals with complete data. The following variables were significantly associated with high overall patient satisfaction: large hospitals, high surgical volume, and low mortality (P patient satisfaction. Low mortality index was consistently found to be associated with high satisfaction across 9 of 10 HCAHPS domains. We found that hospital size, surgical volume, and low mortality were associated with high overall patient satisfaction. However, with the exception of low mortality, favorable surgical outcomes were not consistently associated with high HCAHPS scores. With existing satisfaction surveys, we conclude that factors outside of surgical outcomes appear to influence patients' perceptions of their care.

  14. [Communication with patients in palliative care: favoring cheerfulness and optimism].

    Science.gov (United States)

    de Araújo, Monica Martins Trovo; da Silva, Maria Júlia Paes

    2007-12-01

    The objective of this study was to know the expectations of patients who are in palliative care regarding communication with the nursing team. The data were collected during the first semester of 2005 through half-structured interviews among 39 oncological patients with no healing prognosis subjected to palliative chemotherapy in a hospital institution of the city of São Paulo. After transcription of the speeches, the data were analyzed according to the methodology of content analysis. From the interviewees' speeches four categories emerged. Interpersonal communication proved to be an important attribution to palliative care, with particular attention given to the professional's nonverbal signs for establishing a link of trust, the need for a compassionate presence, the desire not to focus the interaction and the relationship only on the disease and on death and to concentrate instead on cheerful verbal communication favoring optimism and good humor.

  15. Preliminary study of the uranium favorability of Malheur County, Oregon

    International Nuclear Information System (INIS)

    Erikson, E.H.

    1977-11-01

    A reconnaissance study of middle and upper Tertiary volcaniclastic sedimentary and silicic volcanic rocks in Malheur County, Oregon, indicates that, based upon the data available: (1) it is unlikely that sandstone-type uranium deposits exist in sedimentary rocks of north-central Malheur County; and (2) favorable uranium environments are more likely to exist in and adjacent to uraniferous silicic eruptive centers and plugs. Some rhyolites in the northern part of the county contain marginally anomalous uranium abundances (6 to 8 +- 2 ppM U 3 O 8 ), compared with similar rocks in southeastern Oregon. Available uranium from these rocks, as determined by nitric-acid leaching, approaches 50 to 75 percent of the total chemical U 3 O 8 present. One Pliocene rhyolite vitrophyre sample from Duck Butte in western Malheur County contains 9 +- 2 ppM U 3 O 8 . The uranium contents of these rhyolites approach those found in silicic plugs spatially related to uranium deposits in the Lakeview district, Oregon (Erikson and Curry, 1977). It is possible that undiscovered epithermal and (or) supergene uranium deposits may exist in favorable wall rocks subjacent to uraniferous silicic eruptive centers (Duck Butte), calderas (McDermitt caldera to the south and others identified in western Owyhee County, Idaho), and silicic plugs (as in the Lakeview district). With the exception of one small uranium anomaly found in unconsolidated sands in the Grassy Mountain Formation, the sedimentary rocks observed in the study area did not possess abnormal radioactivity or exhibit evidence of uranium mobility and enrichment. Carbonaceous trash is uncommon in these rocks. Gently dipping sandstone members of the Deer Butte Formation (upper Miocene) and local channel sands in the Grassy Mountain Formation (Pliocene) may have once been the most permeable rocks in the Tertiary section; but, there is no evidence to suggest that they were conduits for uranium-bearing solutions

  16. High nevus counts confer a favorable prognosis in melanoma patients.

    Science.gov (United States)

    Ribero, Simone; Davies, John R; Requena, Celia; Carrera, Cristina; Glass, Daniel; Rull, Ramon; Vidal-Sicart, Sergi; Vilalta, Antonio; Alos, Lucia; Soriano, Virtudes; Quaglino, Pietro; Traves, Victor; Newton-Bishop, Julia A; Nagore, Eduardo; Malvehy, Josep; Puig, Susana; Bataille, Veronique

    2015-10-01

    A high number of nevi is the most significant phenotypic risk factor for melanoma and is in part genetically determined. The number of nevi decreases from middle age onward but this senescence can be delayed in patients with melanoma. We investigated the effects of nevus number count on sentinel node status and melanoma survival in a large cohort of melanoma cases. Out of 2,184 melanoma cases, 684 (31.3%) had a high nevus count (>50). High nevus counts were associated with favorable prognostic factors such as lower Breslow thickness, less ulceration and lower mitotic rate, despite adjustment for age. Nevus count was not predictive of sentinel node status. The crude 5- and 10-year melanoma-specific survival rate was higher in melanomas cases with a high nevus count compared to those with a low nevus count (91.2 vs. 86.4% and 87.2 vs. 79%, respectively). The difference in survival remained significant after adjusting for all known melanoma prognostic factors (hazard ratio [HR] = 0.43, confidence interval [CI] = 0.21-0.89). The favorable prognostic value of a high nevus count was also seen within the positive sentinel node subgroup of patients (HR = 0.22, CI = 0.08-0.60). High nevus count is associated with a better melanoma survival, even in the subgroup of patients with positive sentinel lymph node. This suggests a different biological behavior of melanoma tumors in patients with an excess of nevi. © 2015 The Authors. Published by Wiley Periodicals, Inc. on behalf of UICC.

  17. Single-mode 850-nm vertical-cavity surface-emitting lasers with Zn-diffusion and oxide-relief apertures for > 50 Gbit/sec OOK and 4-PAM transmission

    Science.gov (United States)

    Shi, Jin-Wei; Wei, Chia-Chien; Chen, Jyehong; Ledentsov, N. N.; Yang, Ying-Jay

    2017-02-01

    Vertical-cavity surface-emitting lasers (VCSELs) has become the most important light source in the booming market of short-reach (targeted at 56 Gbit/sec data rate per channel (CEI-56G) with the total data rate up to 400 Gbit/sec. However, the serious modal dispersion of multi-mode fiber (MMF), limited speed of VCSEL, and its high resistance (> 150 Ω) seriously limits the >50 Gbit/sec linking distance (50 Gbit/sec transmission due to that it can save one-half of the required bandwidth. Nevertheless, a 4.7 dB optical power penalty and the linearity of transmitter would become issues in the 4-PAM linking performance. Besides, in the modern OI system, the optics transreceiver module must be packaged as close as possible with the integrated circuits (ICs). The heat generated from ICs will become an issue in speed of VSCEL. Here, we review our recent work about 850 nm VCSEL, which has unique Zn-diffusion/oxide-relief apertures and special p- doping active layer with strong wavelength detuning to further enhance its modulation speed and high-temperature (85°C) performances. Single-mode (SM) devices with high-speed ( 26 GHz), reasonable resistance ( 70 Ω) and moderate output power ( 1.5 mW) can be achieved. Error-free 54 Gbit/sec OOK transmission through 1km MMF has been realized by using such SM device with signal processing techniques. Besides, the volterra nonlinear equalizer has been applied in our 4-PAM 64 Gbit/sec transmission through 2-km OM4 MMF, which significantly enhance the linearity of device and outperforms fed forward equalization (FFE) technique. Record high bit-rate distance product of 128.km is confirmed for optical-interconnect applications.

  18. Extremely low losses 14xx single mode laser diode leading to 550-mW output power module with 0-75°C case temperature and 10-W consumption

    Science.gov (United States)

    Burie, J.-R.; Garabedian, P.; Starck, C.; Pagnod-Rossiaux, P.; Bettiati, M.; Do Nascimento, M.; Reygrobellet, J.-N.; Bertreux, J.-C.; Laruelle, F.

    2012-03-01

    High power 14xx laser pumps are more and more required for eye safe industrial, medical, safety and defense applications as well as for increased telecom network capability (e.g. for 100 Gb Ethernet). However, this need of high power requires to control the overall power consumption in a range in line with systems requirements. In this respect, 3S PHOTONICS has developed a 14xx nm single mode laser diode with record internal losses of 1.5 cm-1 compared to the 2.7 cm-1 reported up to now. These lasers are based on p/nBH technology and use the asymmetric waveguide concept to reduce internal losses. The record loss value, coupled to an internal efficiency higher than 0.8, allows realization lasers of 3 mm length with external efficiency higher than 0.5 W.A-1 at 25°C in AR/HR coating configuration. Modules using direct coupling technology were realized. High coupling efficiency is obtained thanks to the 8° x 14° far field pattern of the diode. Output power of 550 mW at 1.8 A is thus obtained, with or without FBG stabilization, with maximum output power above 700mW. Thanks to the lasers' length, voltage at this current level is below 1.9 V, which gives a reduced thermal load. Thus, the overall modules electrical consumption remains lower than 10 W at case temperatures ranging from 0°C to 75°C. The 3 mm length also guaranties high reliability of these laser diodes.

  19. Pig as a Favorable Animal for Taenia Saginata Asiatica Infection

    Directory of Open Access Journals (Sweden)

    Ping-Chin Fan

    2006-01-01

    Full Text Available The epidemiology of Taenia saginata in some parts of Asia is confusing, in that beef does not appear to be the source of infection. In some areas, beef is either not available or not eaten raw, whereas pork at times is eaten uncooked. In light of this situation, we have exposed pigs and other animals to infection with strains of T. saginata to establish their ability to serve as intermediate hosts. Eggs of Taiwan Taenia, Korea Taenia, Indonesia Taenia, Thailand Taenia, Philippines Taenia, Ethiopia Taenia, and Madagascar Taenia were fed to 83 pigs of three strains: 43 Small-Ear Miniature (SEM, 34 Landrace Small-Ear Miniature (L-SEM, and 6 Duroc-Yorkshire-Landrace (DYL. We also fed the eggs to 10 Holstein calves, 17 Sannean goats, and 4 monkeys (Macaca cyclopis. We succeeded in infecting SEM (infection rate 88%, cysticercus recovery rate 19.1%, L-SEM (83%, 1.1%, and DYL (100%, 0.3% pigs with Taiwan Taenia; SEM (100%, 1.7%, L-SEM (100%, 5.6%, and DYL (100%, 0.06% pigs with Korea Taenia; SEM (100%, 22% and L-SEM (100%, 1.6% pigs with Indonesia Taenia; SEM (75%, 0.06% pigs with Thailand Taenia SEM (100%, 11% pigs with Philippines Taenia; SEM (80%, 0.005% pigs with Ethiopia Taenia; SEM (100%, 0.2% pigs with Madagascar Taenia. Holstein calves became infected with Taenia from Taiwan (100%, 1.1%, Korea (100%, 0.03%, Thailand (100%, 0.2%, and the Philippines (100%, 6%; however, the cysticerci of Taenia from Korea, Thailand, and the Philippines were degenerated and/or calcified. Sannean goats became infected with Taenia from Taiwan (33%, 0.01% and Korea (50%, 0.02%, while monkeys became infected with Taenia from Taiwan (50%, 0.01%. However, the cysticerci were degenerated and/or calcified. Therefore, these strains of pig seem to be favorable animal models for experimental studies of T. saginata-like tapeworms, with the SEM pig the most favorable.

  20. Pig as a favorable animal for Taenia saginata asiatica infection.

    Science.gov (United States)

    Fan, Ping-Chin; Chung, Win-Cheng; Lin, Chung-Yung; Wu, Chin-Cheng

    2006-01-01

    The epidemiology of Taenia saginata in some parts of Asia is confusing, in that beef does not appear to be the source of infection. In some areas, beef is either not available or not eaten raw, whereas pork at times is eaten uncooked. In light of this situation, we have exposed pigs and other animals to infection with strains of T. saginata to establish their ability to serve as intermediate hosts. Eggs of Taiwan Taenia, Korea Taenia, Indonesia Taenia, Thailand Taenia, Philippines Taenia, Ethiopia Taenia, and Madagascar Taenia were fed to 83 pigs of three strains: 43 Small-Ear Miniature (SEM), 34 Landrace Small-Ear Miniature (L-SEM), and 6 Duroc-Yorkshire-Landrace (DYL). We also fed the eggs to 10 Holstein calves, 17 Sannean goats, and 4 monkeys (Macaca cyclopis). We succeeded in infecting SEM (infection rate 88%, cysticercus recovery rate 19.1%), L-SEM (83%, 1.1%), and DYL (100%, 0.3%) pigs with Taiwan Taenia; SEM (100%, 1.7%), L-SEM (100%, 5.6%), and DYL (100%, 0.06%) pigs with Korea Taenia; SEM (100%, 22%) and L-SEM (100%, 1.6%) pigs with Indonesia Taenia; SEM (75%, 0.06%) pigs with Thailand Taenia SEM (100%, 11%) pigs with Philippines Taenia; SEM (80%, 0.005%) pigs with Ethiopia Taenia; SEM (100%, 0.2%) pigs with Madagascar Taenia. Holstein calves became infected with Taenia from Taiwan (100%, 1.1%), Korea (100%, 0.03%), Thailand (100%, 0.2%), and the Philippines (100%, 6%); however, the cysticerci of Taenia from Korea, Thailand, and the Philippines were degenerated and/or calcified. Sannean goats became infected with Taenia from Taiwan (33%, 0.01%) and Korea (50%, 0.02%), while monkeys became infected with Taenia from Taiwan (50%, 0.01%). However, the cysticerci were degenerated and/ or calcified. Therefore, these strains of pig seem to be favorable animal models for experimental studies of T. saginata-like tapeworms, with the SEM pig the most favorable.

  1. [Incidence of factors favoring recurrent foot ulcers in diabetic patients].

    Science.gov (United States)

    Diouri, A; Slaoui, Z; Chadli, A; El Ghomari, H; Kebbou, M; Marouan, F; Farouqi, A; Ababou, M R

    2002-12-01

    Patients with foot ulcers have a high risk of relapse and amputation. Several studies have reported that 28 to 51% of amputated diabetics will have a second amputation of the lower limb within five years of the first amputation. The purpose of this study was to assess the incidence of factors favoring relapse within two years. One hundred ten diabetic patients were treated for foot lesions in the Casablanca Ibn Rochd university hospital between 1997 and 2000. Ninety of these patients attended review consultations. There were 42 cases of relapse (46.6%). Male gender predominated in the relapse patients with a sex ratio of 3.2. Mean age at relapse was 55 years; 71.5% of the patients had type 2 diabetes. Lesions observed were neuropathic ulcer (n=23), arterial ulcer (n=6), infected wounds (n=13). Revealing factors were burns and wounds. The main risk factors were neuropathy (n=23, 52%), neuroarteriopathy (n=12, 31%), peur arteriopathy (n=6, 12%). Patients who relapsed (n=42) were significantly different from patients who did not relapse (n=48) for gender, presence or absence of neuropathy, and presence or absence of arteriopathy. Secondary preventive measures against these risk factors, medical care, and specialized follow-up were satisfactory in these patients. our findings illustrate the importance of specialized management of diabetic patients with foot lesions. Adequate care of the lesions and preventive measures against risk factors are needed.

  2. Immunosuppression with cyclophosphamide favors reinfection with recombinant Toxoplasma gondii strains

    Directory of Open Access Journals (Sweden)

    Silva L.A.

    2012-08-01

    Full Text Available The aim of this study was to verify the effect of immunosuppression by cyclophosphamide (Cy on susceptibility of BALB/c mice subjected to challenge with recombinant strains of Toxoplasma gondii. Animals were prime infected with the D8 (recombinant I/III or the ME49 (type II non-virulent strains, weekly immunosuppressed with Cy and challenged with the CH3 or EGS virulent strains (I/III. Parasites recovered from surviving mice were submitted to PCR-RFLP analysis to confirm co-infection. Prime-infection with the D8 strain conferred more protection against challenge with the CH3 and EGS strains when compared with ME49 prime infection. Cy treatment caused significant leukopenia in the infected mice, what probably favors reinfection after challenge. Reinfection was associated with increased levels of IgA. Otherwise, Cy-treated mice presented significantly lower IgA levels after challenge, suggesting involvement of this immunoglobulin on protection against reinfection. In conclusion, BALB/c mice susceptibility to reinfection by T. gondii is related to genetic differences among the strains used for primary and challenge infections. Alteration of the host’s immune integrity by Cy probably compromises the protection previously established by primary infection.

  3. Paleozoic unconformities favorable for uranium concentration in northern Appalachian basin

    International Nuclear Information System (INIS)

    Dennison, J.M.

    1986-01-01

    Unconformities can redistribute uranium from protore rock as ground water moves through poorly consolidated strata beneath the erosion surface, or later moves along the unconformity. Groundwater could migrate farther than in present-day lithified Paleozoic strata in the Appalachian basin, now locally deformed by the Taconic and Allegheny orogenies. Several paleoaquifer systems could have developed uranium geochemical cells. Sandstone mineralogy, occurrences of fluvial strata, and reduzate facies are important factors. Other possibilities include silcrete developed during desert exposure, and uranium concentrated in paleokarst. Thirteen unconformities are evaluated to determine favorable areas for uranium concentration. Cambrian Potsdam sandstone (New York) contains arkoses and possible silcretes just above crystalline basement. Unconformities involving beveled sandstones and possible fluvial strata include Cambrian Hardyston sandstone (New Jersey), Cambrian Potsdam Sandstone (New York), Ordovician Oswego and Juniata formations (Pennsylvania and New York), Silurian Medina Group (New York), and Silurian Vernon, High Falls, and Longwood formations (New York and New Jersey). Devonian Catskill Formation is beveled by Pennsylvanian strata (New York and Pennsylvania). The pre-Pennsylvanian unconformity also bevels Lower Mississippian Pocono, Knapp, and Waverly strata (Pennsylvania, New York, and Ohio), truncates Upper Mississippian Mauch Chunk Formation (Pennsylvania), and forms paleokarst on Mississippian Loyalhanna Limestone (Pennsylvania) and Maxville Limestone (Ohio). Strata associated with these unconformities contain several reports of uranium. Unconformities unfavorable for uranium concentration occur beneath the Middle Ordovician (New York), Middle Devonian (Ohio and New York), and Upper Devonian (Ohio and New York); these involve marine strata overlying marine strata and probably much submarine erosion

  4. Musical FAVORS: Reintroducing music to adult cochlear implant users.

    Science.gov (United States)

    Plant, Geoff

    2015-09-01

    Music represents a considerable challenge for many adult users of cochlear implants (CIs). Around half of adult CI users report that they do not find music enjoyable, and, in some cases, despite enhanced speech perception skills, this leads to considerable frustration and disappointment for the CI user. This paper presents suggestions to improve the musical experiences of deafened adults with CIs. Interviews with a number of adult CI users revealed that there were a number of factors which could lead to enhanced music experiences. The acronym FAVORS (familiar music, auditory-visual access, open-mindedness, and simple arrangements) summarizes the factors that have been identified, which can help CI users in their early music listening experiences. Each of these factors is discussed in detail, along with suggestions for how they can be used in therapy sessions. The use of a group approach (music focus groups) is also discussed and an overview of the approach and exercises used is presented. The importance of live music experiences is also discussed.

  5. Heterolytic dissociative adsorption state of dihydrogen favored by interfacial defects

    Science.gov (United States)

    Song, Zhenjun; Hu, Hanshi; Xu, Hu; Li, Yong; Cheng, Peng; Zhao, Bin

    2018-03-01

    The atomic-scale insight into dihydrogen on MgO(001) surface deposited on molybdenum substrate with interfacial defects was investigated in detail by employing density functional methods Here we report novel dissociative adsorption behaviors of single hydrogen molecule on the usually inert oxide surfaces, with consideration of two types of dissociation schemes. The heterolytic dissociation state -Mg(H)-O(H)- of dihydrogen is impossible to obtain on neighboring O-Mg sites of perfect bulk MgO(001) terraces. Unusually, the hydrogen molecule can form heterolytic fragmentation states on metal supported MgO(001) films with very low activation barrier (0.398 eV), and the heterolytic dissociation state is much more favorable than homolytic dissociation state both energetically and kinetically in all cases. Electronic properties and bonding attribution of adsorbates and the oxide-metal hybrid structure are revealed by analyzing density of states, differential charge densities, orbital interaction and electron localization function. The characteristic changes to the property and activity of magnesia (001) can have potential application in catalytic reactions.

  6. Competition favors elk over beaver in a riparian willow ecosystem

    Science.gov (United States)

    Baker, B.W.; Peinetti, H.R.; Coughenour, M.C.; Johnson, T.L.

    2012-01-01

    Beaver (Castor spp.) conservation requires an understanding of their complex interactions with competing herbivores. Simulation modeling offers a controlled environment to examine long-term dynamics in ecosystems driven by uncontrollable variables. We used a new version of the SAVANNA ecosystem model to investigate beaver (C. Canadensis) and elk (Cervus elapses) competition for willow (Salix spp.). We initialized the model with field data from Rocky Mountain National Park, Colorado, USA, to simulate a 4-ha riparian ecosystem containing beaver, elk, and willow. We found beaver persisted indefinitely when elk density was or = 30 elk km_2. The loss of tall willow preceded rapid beaver declines, thus willow condition may predict beaver population trajectory in natural environments. Beaver were able to persist with slightly higher elk densities if beaver alternated their use of foraging sites in a rest-rotation pattern rather than maintained continuous use. Thus, we found asymmetrical competition for willow strongly favored elk over beaver in a simulated montane ecosystem. Finally, we discuss application of the SAVANNA model and mechanisms of competition relative to beaver persistence as metapopulations, ecological resistance and alternative state models, and ecosystem regulation.

  7. Prediction of favorable outcome by percent improvement in patients with acute ischemic stroke treated with endovascular stent thrombectomy.

    Science.gov (United States)

    Cao, Yuezhou; Wang, Shuiping; Sun, Wen; Dai, Qiliang; Li, Wei; Cai, Jin; Fan, Xinying; Zhu, Wusheng; Xiong, Yunyun; Han, Yunfei; Zi, Wenjie; Yang, Shiquan; Chen, Jia; Liu, Xinfeng

    2017-04-01

    Our objective was to investigate a method for assessing early improvement and its predictive value for 3-month functional outcome in patients treated with EST. A total of 97 consecutive AIS patients undergoing EST were prospectively collected and retrospective reviewed. Data on demographics, vascular risk factors, admission National Institutes of Health Stroke Scale (NIHSS) score, 24-h NIHSS score, reperfusion and collateral formation were collected. Percent improvement was defined as ([baseline NIHSS score-24-h NIHSS score]/baseline NIHSS score×100%), while absolute improvement was calculated by the difference between scores (baseline NIHSS score-24-h NIHSS score). A 3-month functional outcome was assessed using the modified Rankin Scale (mRS). Favorable outcome was defined as a mRS score of 0-2. Areas under the receiver-operating characteristic (ROC) curve (AUC) for percent improvement and absolute improvement in predicting favorable outcome was compared. Finally, we investigated the independent predictors of improvement at 24h after EST and its relationship with favorable outcome. Pairwise comparison of ROC curves revealed that percent improvement had larger AUC than absolute improvement (p=0.004). Rapid neurological improvement (RNI), defined as percent improvement ⩾30%, was a powerful predictor of favorable outcome (odds ratio [OR] 7.63, confidence interval [CI]: 2.65-21.96; pRNI. RNI predicted 3-month favorable outcome in AIS patients treated with EST. Good collaterals and short ORT are independent predictors of RNI. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Partially reversible quantum operations and their information-theoretical properties

    CERN Document Server

    Ban, M

    2003-01-01

    Partial reversibility of quantum operations (or quantum channels) is considered from the information-theoretical point of view. The necessary and sufficient condition for quantum operations to be partially reversible is shown. The condition can be expressed in terms of information-theoretical quantities (von Neumann entropy and PSI-information). The quantum information-theoretical meanings of the condition are discussed. The results are compared with those obtained for completely reversible quantum operations. The PSI-information is calculated for the quantum depolarizing channel of a qubit and the linear dissipative channel of a single-mode bosonic system.

  9. What favors the occurrence of subduction mega-earthquakes?

    Science.gov (United States)

    Brizzi, Silvia; Funiciello, Francesca; Corbi, Fabio; Sandri, Laura; van Zelst, Iris; Heuret, Arnauld; Piromallo, Claudia; van Dinther, Ylona

    2017-04-01

    Most of mega-earthquakes (MEqs; Mw > 8.5) occur at shallow depths along the subduction thrust fault (STF). The contribution of each subduction zone to the globally released seismic moment is not homogenous, as well as the maximum recorded magnitude MMax. Highlighting the ingredients likely responsible for MEqs nucleation has great implications for hazard assessment. In this work, we investigate the conditions favoring the occurrence of MEqs with a multi-disciplinary approach based on: i) multivariate statistics, ii) analogue- and iii) numerical modelling. Previous works have investigated the potential dependence between STF seismicity and various subduction zone parameters using simple regression models. Correlations are generally weak due to the limited instrumental seismic record and multi-parameter influence, which make the forecasting of the potential MMax rather difficult. To unravel the multi-parameter influence, we perform a multivariate statistical study (i.e., Pattern Recognition, PR) of the global database on convergent margins (Heuret et al., 2011), which includes seismological, geometrical, kinematic and physical parameters of 62 subduction segments. PR is based on the classification of objects (i.e., subduction segments) belonging to different classes through the identification of possible repetitive patterns. Tests have been performed using different MMax datasets and combination of inputs to indirectly test the stability of the identified patterns. Results show that the trench-parallel width of the subducting slab (Wtrench) and the sediment thickness at the trench (Tsed) are the most recurring parameters for MEqs occurrence. These features are mostly consistent, independently of the MMax dataset and combination of inputs used for the analysis. MEqs thus seem to be promoted for high Wtrench and Tsed, as their combination may potentially favor extreme (i.e., in the order of thousands of km) trench-parallel rupture propagation. To tackle the

  10. Preliminary study of uranium favorability of the Boulder batholith, Montana

    Energy Technology Data Exchange (ETDEWEB)

    Castor, S.B.; Robins, J.W.

    1978-01-01

    The Boulder batholith of southwestern Montana is a composite Late Cretaceous intrusive mass, mostly composed of quartz monzonite and granodiorite. This study was not restricted to the plutonic rocks; it also includes younger rocks that overlie the batholith, and older rocks that it intrudes. The Boulder batholith area has good overall potential for economic uranium deposits, because its geology is similar to that of areas that contain economic deposits elsewhere in the world, and because at least 35 uranium occurrences of several different types are present. Potential is greatest for the occurrence of small uranium deposits in chalcedony veins and base-metal sulfide veins. Three areas may be favorable for large, low-grade deposits consisting of a number of closely spaced chalcedony veins and enriched wall rock; the Mooney claims, the Boulder area, and the Clancy area. In addition, there is a good possibility of by-product uranium production from phosphatic black shales in the project area. The potential for uranium deposits in breccia masses that cut prebatholith rocks, in manganese-quartz veins near Butte, and in a shear zone that cuts Tertiary rhyolite near Helena cannot be determined on the basis of available information. Low-grade, disseminated, primary uranium concentrations similar to porphyry deposits proposed by Armstrong (1974) may exist in the Boulder batholith, but the primary uranium content of most batholith rocks is low. The geologic environment adjacent to the Boulder batholith is similar in places to that at the Midnite mine in Washington. Some igneous rocks in the project area contain more than 10 ppM U/sub 3/O/sub 8/, and some metasedimentary rocks near the batholith contain reductants such as sulfides and carbonaceous material.

  11. Cordilleran metamorphic core complexes and their uranium favorability. Final report

    International Nuclear Information System (INIS)

    Coney, P.J.; Reynolds, S.J.

    1980-11-01

    The objective of this report is to provide a descriptive body of knowledge on Cordilleran metamorphic core complexes including their lithologic and structural characteristics, their distribution within the Cordillera, and their evolutionary history and tectonic setting. The occurrence of uranium in the context of possibility for uranium concentration is also examined. Chapter 1 is an overview of Cordilleran metamorphic core complexes which describes their physical characteristics, tectonic setting and geologic history. This overview is accompanied by a tectonic map. Chapter 2 is a discussion of the mantled gneiss dome concept. The purpose of including this work is to provide a basic history of this concept and to describe the characteristics and distribution of gneiss domes throughout the world to enable one to compare and contrast them with the metamorphic core complexes as discussed in this report. Some gneiss domes are known producers of uranium (as are also some core complexes). Chapter 3 is an examination of the effects of the core complex process on adjacent sedimentary and volcanic cover terranes. Also included is a discussion of the kinematic significance of these cover terranes as they are related to process within the cores of the complexes. Some of the cover terranes have uranium prospects in them. Chapter 4 is a detailed discussion of uranium in Cordilleran metamorphic core complexes and includes the conceptual basis for the various types of occurrences and the processes that might favor concentration of uranium. The report is supported by a 5-part Appendix. The majority of the core complexes discussed in this report either do not appear or are not recognizable on existing published geologic maps

  12. Preliminary study of uranium favorability of the Boulder batholith, Montana

    International Nuclear Information System (INIS)

    Castor, S.B.; Robins, J.W.

    1978-01-01

    The Boulder batholith of southwestern Montana is a composite Late Cretaceous intrusive mass, mostly composed of quartz monzonite and granodiorite. This study was not restricted to the plutonic rocks; it also includes younger rocks that overlie the batholith, and older rocks that it intrudes. The Boulder batholith area has good overall potential for economic uranium deposits, because its geology is similar to that of areas that contain economic deposits elsewhere in the world, and because at least 35 uranium occurrences of several different types are present. Potential is greatest for the occurrence of small uranium deposits in chalcedony veins and base-metal sulfide veins. Three areas may be favorable for large, low-grade deposits consisting of a number of closely spaced chalcedony veins and enriched wall rock; the Mooney claims, the Boulder area, and the Clancy area. In addition, there is a good possibility of by-product uranium production from phosphatic black shales in the project area. The potential for uranium deposits in breccia masses that cut prebatholith rocks, in manganese-quartz veins near Butte, and in a shear zone that cuts Tertiary rhyolite near Helena cannot be determined on the basis of available information. Low-grade, disseminated, primary uranium concentrations similar to porphyry deposits proposed by Armstrong (1974) may exist in the Boulder batholith, but the primary uranium content of most batholith rocks is low. The geologic environment adjacent to the Boulder batholith is similar in places to that at the Midnite mine in Washington. Some igneous rocks in the project area contain more than 10 ppM U 3 O 8 , and some metasedimentary rocks near the batholith contain reductants such as sulfides and carbonaceous material

  13. Survey of the Favorable Conditions for Magnetosonic Wave Excitation

    Science.gov (United States)

    Kim, Kyung-Chan; Shprits, Yuri

    2018-01-01

    The ratio of the proton ring velocity (VR) to the local Alfven speed (VA), in addition to proton ring distributions, plays a key factor in the excitation of magnetosonic waves at frequencies between the proton cyclotron frequency fcp and the lower hybrid resonance frequency fLHR in the Earth's magnetosphere. Here we investigate whether there is a statistically significant relationship between occurrences of proton rings and magnetosonic waves both outside and inside the plasmapause using particle and wave data from Van Allen Probe-A during the time period of October 2012 to December 2015. We also perform a statistical survey of the ratio of the ring energy (ER, corresponding to VR) to the Alfven energy (EA, corresponding to VA) to determine the favorable conditions under which magnetosonic waves in each of two frequency bands (fcp 0.5 fLHR and 0.5 fLHR LHR) can be excited. The results show that the magnetosonic waves in both frequency bands occur around the postnoon (12-18 magnetic local time, MLT) sector outside the plasmapause when ER is comparable to or lower than EA, and those in lower-frequency bands (fcp 0.5 fLHR) occur around the postnoon sector inside the plasmapause when ER/EA > 9. However, there is one discrepancy between occurrences of proton rings and magnetosonic waves in low-frequency bands around the prenoon sector (6-12 MLT) outside the plasmapause, which suggests either that the waves may have propagated during active time from the postnoon sector after being excited during quiet time, or they may have locally excited in the prenoon sector during active time.

  14. On the Favorable Estimation for Fitting Heavy Tailed Data

    Czech Academy of Sciences Publication Activity Database

    Stehlík, M.; Potocký, R.; Waldl, H.; Fabián, Zdeněk

    2010-01-01

    Roč. 25, č. 3 (2010), s. 485-503 ISSN 0943-4062 Grant - others:ASO(SK) SK-0607-BA-018; VEGA(SK) 1/0077/09; 50p14(CZ-AT) AKTION; AKTION(CZ-AT) 54p13 Institutional research plan: CEZ:AV0Z10300504 Keywords : heavy-tailed distribution * exact likelihood ratio test * T-score moment estimator * insurance * Basel II Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 0.500, year: 2010

  15. Modification of a Limbed Robot to Favor Climbing

    Science.gov (United States)

    Okon, Avi; Kennedy, Brett; Garrett, Michael; Magnone, Lee

    2006-01-01

    The figure shows the LEMUR IIb, which is a modified version of the LEMUR II the second generation of the Limbed Excursion Mechanical Utility Robot (LEMUR). Except as described below, the LEMUR IIb hardware is mostly the same as that of the LEMUR II. The IIb and II versions differ in their kinematic configurations and characteristics associated with their kinematic configurations. The differences are such that relative to the LEMUR II, the LEMUR IIb is simpler and is better suited to climbing on inclined surfaces. The first-generation LEMUR, now denoted the LEMUR I, was described in Six-Legged Experimental Robot (NPO-20897), NASA Tech Briefs, Vol. 25, No. 12 (December 2001), page 58. The LEMUR II was described in Second-Generation Six-Limbed Experimental Robot (NPO-35140) NASA Tech Briefs, Vol. 28, No. 11 (November 2004), page 55. To recapitulate: the LEMUR I and LEMUR II were six-legged or sixlimbed robots for demonstrating robotic capabilities for assembly, maintenance, and inspection. They were designed to be capable of walking autonomously along a truss structure toward a mechanical assembly at a prescribed location. They were equipped with stereoscopic video cameras and image-data-processing circuitry for navigation and mechanical operations. They were also equipped with wireless modems, through which they could be commanded remotely. Upon arrival at a mechanical assembly, the LEMUR I would perform simple mechanical operations by use of one or both of its front legs (or in the case of the LEMUR II, any of its limbs could be used to perform mechanical operations). Either LEMUR could also transmit images to a host computer. The differences between the LEMUR IIb and the LEMUR II are the following: Whereas the LEMUR II had six limbs, the LEMUR IIb has four limbs. This change has reduced both the complexity and mass of the legs and of the overall robot. Whereas each limb of the LEMUR II had four degrees of freedom (DOFs), each limb of the LEMUR IIb has three DOFs

  16. Favoring the unfavored: Selective electrochemical nitrogen fixation using a reticular chemistry approach.

    Science.gov (United States)

    Lee, Hiang Kwee; Koh, Charlynn Sher Lin; Lee, Yih Hong; Liu, Chong; Phang, In Yee; Han, Xuemei; Tsung, Chia-Kuang; Ling, Xing Yi

    2018-03-01

    Electrochemical nitrogen-to-ammonia fixation is emerging as a sustainable strategy to tackle the hydrogen- and energy-intensive operations by Haber-Bosch process for ammonia production. However, current electrochemical nitrogen reduction reaction (NRR) progress is impeded by overwhelming competition from the hydrogen evolution reaction (HER) across all traditional NRR catalysts and the requirement for elevated temperature/pressure. We achieve both excellent NRR selectivity (~90%) and a significant boost to Faradic efficiency by 10 percentage points even at ambient operations by coating a superhydrophobic metal-organic framework (MOF) layer over the NRR electrocatalyst. Our reticular chemistry approach exploits MOF's water-repelling and molecular-concentrating effects to overcome HER-imposed bottlenecks, uncovering the unprecedented electrochemical features of NRR critical for future theoretical studies. By favoring the originally unfavored NRR, we envisage our electrocatalytic design as a starting point for high-performance nitrogen-to-ammonia electroconversion directly from water vapor-abundant air to address increasing global demand of ammonia in (bio)chemical and energy industries.

  17. Cabibbo-Kobayashi-Maskawa-favored B decays to a scalar meson and a D meson

    Energy Technology Data Exchange (ETDEWEB)

    Zou, Zhi-Tian; Li, Ying [Yantai University, Department of Physics, Yantai (China); Liu, Xin [Jiangsu Normal University, School of Physics and Electronic Engineering, Xuzhou (China)

    2017-12-15

    In this work, we attempt to study the Cabibbo-Kobayashi-Maskawa-favored B → anti DS (''S'' denoting the scalar meson) decays within the perturbative QCD approach at the leading order and the leading power. Although the light scalar mesons are widely perceived as primarily the four-quark bound states, in practice it is hard for us to make quantitative predictions based on the four-quark picture for light scalars. Hence, we calculate the decays with light scalars in the two-quark model. For the decays with scalar mesons above 1 GeV, we have explored two possible scenarios, depending on whether the light scalars are treated as the lowest lying q anti q states or four-quark particles. In total, we calculated the branching fractions of 72 decay modes, and most of them are in the range 10{sup -4}-10{sup -7}, which are measurable in the on-going LHCb experiment and the forthcoming Belle-II experiment. Moreover, since in the standard model these decays occur only through tree operators and have no CP asymmetries, any deviation will be a signal of new physics beyond the standard model. Despite large uncertainties induced by nonperturbative parameters and corrections of high order and high power, our results and discussions will be useful for the on-going LHCb and the forthcoming Belle-II experiments. (orig.)

  18. Anticipated detection of favorable periods for wind energy production by means of information theory

    Science.gov (United States)

    Vogel, Eugenio; Saravia, Gonzalo; Kobe, Sigismund; Schumann, Rolf; Schuster, Rolf

    Managing the electric power produced by different sources requires mixing the different response times they present. Thus, for instance, coal burning presents large time lags until operational conditions are reached while hydroelectric generation can react in a matter of some seconds or few minutes to reach the desired productivity. Wind energy production (WEP) can be instantaneously fed to the network to save fuels with low thermal inertia (gas burning for instance), but this source presents sudden variations within few hours. We report here for the first time a method based on information theory to handle WEP. This method has been successful in detecting dynamical changes in magnetic transitions and variations of stock markets. An algorithm called wlzip based on information recognition is used to recognize the information content of a time series. We make use of publically available energy data in Germany to simulate real applications. After a calibration process the system can recognize directly on the WEP data the onset of favorable periods of a desired strength. Optimization can lead to a few hours of anticipation which is enough to control the mixture of WEP with other energy sources, thus saving fuels.

  19. A generalização a partir do tratamento com fricativas: ambientes favoráveis versus ambientes pouco favoráveis e neutros The generalization through the treatment with fricatives: favorable environments versus unfavorable and neutral environments

    Directory of Open Access Journals (Sweden)

    Fernanda Marafiga Wiethan

    2013-01-01

    Full Text Available O objetivo deste estudo foi analisar e comparar a ocorrência e os tipos de generalização observados a partir do tratamento das fricativas /z/, /ζ/ e /k/ em dois grupos de crianças, um utilizando palavras com contextos fonológicos favoráveis e outro os contextos pouco favoráveis e neutros. Seis crianças com desvio fonológico e idades entre 4:7 e 7:8 participaram do estudo com a autorização dos responsáveis. Realizaram-se avaliações fonoaudiológicas e complementares para o diagnóstico do desvio fonológico. Os sujeitos foram pareados de acordo com a gravidade do desvio, sexo, faixa etária e aspectos do sistema fonológico em relação aos fonemas alterados. Metade das crianças foi tratada com palavras em que os fonemas /z/, /ζ/ e /k/ encontravam-se em ambientes fonológicos favoráveis e a outra metade com ambientes pouco favoráveis e neutros. Foram realizadas oito sessões e, após estas, nova avaliação de fala foi realizada para verificar os tipos de generalização obtidos. Os percentuais de generalizações foram comparados entre os grupos por meio do teste estatístico de Mann-Whitney (pThe aim of this study was to analyze and compare the occurrence and the types of generalization observed through the treatment of the fricatives /z/, /ζ/ and /k/ in two groups of children, one using words with favorable phonological contexts and another with unfavorable and neutral contexts. Six children with phonological disorder between 4:7 and 7:8 year-old participated in the study, with their parents' authorization. There were speech-language and complementary evaluations to diagnose the phonological disorder. The subjects were matched according to the severity of the phonological disorder, sex, age and aspects of the phonological system in relation to the altered phonemes. Half the children were treated with words in which the phonemes /z/, /ζ/ and /k/ were in favorable phonological environments and the other half with unfavorable

  20. Uranium favorability of late Eocene through Pliocene rocks of the South Texas Coastal Plain

    Energy Technology Data Exchange (ETDEWEB)

    Quick, J.V.; Thomas, N.G.; Brogdon, L.D.; Jones, C.A.; Martin, T.S.

    1977-02-01

    The results of a subsurface uranium favorability study of Tertiary rocks (late Eocene through Pliocene) in the Coastal Plain of South Texas are given. In ascending order, these rock units include the Yegua Formation, Jackson Group, Frio Clay, Catahoula Tuff, Oakville Sandstone, and Goliad Sand. The Vicksburg Group, Anahuac Formation, and Fleming Formation were not considered because they have unfavorable lithologies. The Yegua Formation, Jackson Group, Frio Clay, Catahoula Tuff, Oakville Sandstone, and Goliad Sand contain sandstones that may be favorable uranium hosts under certain environmental and structural conditions. All except the Yegua are known to contain ore-grade uranium deposits. Yegua and Jackson sandstones are found in strand plain-barrier bar systems that are aligned parallel to depositional and structural strike. These sands grade into shelf muds on the east, and lagoonal sediments updip toward the west. The lagoonal sediments in the Jackson are interrupted by dip-aligned fluvial systems. In both units, favorable areas are found in the lagoonal sands and in sands on the updip side of the strand-plain system. Favorable areas are also found along the margins of fluvial systems in the Jackson. The Frio and Catahoula consist of extensive alluvial-plain deposits. Favorable areas for uranium deposits are found along the margins of the paleo-channels where favorable structural features and numerous optimum sands are present. The Oakville and Goliad Formations consist of extensive continental deposits of fluvial sandstones. In large areas, these fluvial sandstones are multistoried channel sandstones that form very thick sandstone sequences. Favorable areas are found along the margins of the channel sequences. In the Goliad, favorable areas are also found on the updip margin of strand-plain sandstones where there are several sandstones of optimum thickness.

  1. Uranium favorability of late Eocene through Pliocene rocks of the South Texas Coastal Plain

    International Nuclear Information System (INIS)

    Quick, J.V.; Thomas, N.G.; Brogdon, L.D.; Jones, C.A.; Martin, T.S.

    1977-02-01

    The results of a subsurface uranium favorability study of Tertiary rocks (late Eocene through Pliocene) in the Coastal Plain of South Texas are given. In ascending order, these rock units include the Yegua Formation, Jackson Group, Frio Clay, Catahoula Tuff, Oakville Sandstone, and Goliad Sand. The Vicksburg Group, Anahuac Formation, and Fleming Formation were not considered because they have unfavorable lithologies. The Yegua Formation, Jackson Group, Frio Clay, Catahoula Tuff, Oakville Sandstone, and Goliad Sand contain sandstones that may be favorable uranium hosts under certain environmental and structural conditions. All except the Yegua are known to contain ore-grade uranium deposits. Yegua and Jackson sandstones are found in strand plain-barrier bar systems that are aligned parallel to depositional and structural strike. These sands grade into shelf muds on the east, and lagoonal sediments updip toward the west. The lagoonal sediments in the Jackson are interrupted by dip-aligned fluvial systems. In both units, favorable areas are found in the lagoonal sands and in sands on the updip side of the strand-plain system. Favorable areas are also found along the margins of fluvial systems in the Jackson. The Frio and Catahoula consist of extensive alluvial-plain deposits. Favorable areas for uranium deposits are found along the margins of the paleo-channels where favorable structural features and numerous optimum sands are present. The Oakville and Goliad Formations consist of extensive continental deposits of fluvial sandstones. In large areas, these fluvial sandstones are multistoried channel sandstones that form very thick sandstone sequences. Favorable areas are found along the margins of the channel sequences. In the Goliad, favorable areas are also found on the updip margin of strand-plain sandstones where there are several sandstones of optimum thickness

  2. Loblolly pine growth following operational vegetation management treatments compares favorably to that achieved in complete vegetation control research trials

    Science.gov (United States)

    Dwight K. Lauer; Harold E. Quicke

    2010-01-01

    Different combinations of chemical site prep and post-plant herbaceous weed control installed at three Upper Coastal Plain locations were compared in terms of year 3 loblolly (Pinus taeda L.) pine response to determine the better vegetation management regimes. Site prep treatments were different herbicide rates applied in either July or October. Site...

  3. Validation of favor code linear elastic fracture solutions for finite-length flaw geometries

    International Nuclear Information System (INIS)

    Dickson, T.L.; Keeney, J.A.; Bryson, J.W.

    1995-01-01

    One of the current tasks within the US Nuclear Regulatory Commission (NRC)-funded Heavy Section Steel Technology Program (HSST) at Oak Ridge National Laboratory (ORNL) is the continuing development of the FAVOR (Fracture, analysis of Vessels: Oak Ridge) computer code. FAVOR performs structural integrity analyses of embrittled nuclear reactor pressure vessels (RPVs) with stainless steel cladding, to evaluate compliance with the applicable regulatory criteria. Since the initial release of FAVOR, the HSST program has continued to enhance the capabilities of the FAVOR code. ABAQUS, a nuclear quality assurance certified (NQA-1) general multidimensional finite element code with fracture mechanics capabilities, was used to generate a database of stress-intensity-factor influence coefficients (SIFICs) for a range of axially and circumferentially oriented semielliptical inner-surface flaw geometries applicable to RPVs with an internal radius (Ri) to wall thickness (w) ratio of 10. This database of SIRCs has been incorporated into a development version of FAVOR, providing it with the capability to perform deterministic and probabilistic fracture analyses of RPVs subjected to transients, such as pressurized thermal shock (PTS), for various flaw geometries. This paper discusses the SIFIC database, comparisons with other investigators, and some of the benchmark verification problem specifications and solutions

  4. Are human embryos Kantian persons?: Kantian considerations in favor of embryonic stem cell research

    Directory of Open Access Journals (Sweden)

    Manninen Bertha

    2008-01-01

    operation. Finally, I will end the paper by drawing from Allen Wood's work in Kantian philosophy in order to generate an argument in favor of hESCR.

  5. Are human embryos Kantian persons?: Kantian considerations in favor of embryonic stem cell research.

    Science.gov (United States)

    Manninen, Bertha Alvarez

    2008-01-31

    One argument used by detractors of human embryonic stem cell research (hESCR) invokes Kant's formula of humanity, which proscribes treating persons solely as a means to an end, rather than as ends in themselves. According to Fuat S. Oduncu, for example, adhering to this imperative entails that human embryos should not be disaggregated to obtain pluripotent stem cells for hESCR. Given that human embryos are Kantian persons from the time of their conception, killing them to obtain their cells for research fails to treat them as ends in themselves. This argument assumes two points that are rather contentious given a Kantian framework. First, the argument assumes that when Kant maintains that humanity must be treated as an end in itself, he means to argue that all members of the species Homo sapiens must be treated as ends in themselves; that is, that Kant regards personhood as co-extensive with belonging to the species Homo sapiens. Second, the argument assumes that the event of conception is causally responsible for the genesis of a Kantian person and that, therefore, an embryo is a Kantian person from the time of its conception. In this paper, I will present challenges against these two assumptions by engaging in an exegetical study of some of Kant's works. First, I will illustrate that Kant did not use the term "humanity" to denote a biological species, but rather the capacity to set ends according to reason. Second, I will illustrate that it is difficult given a Kantian framework to denote conception (indeed any biological event) as causally responsible for the creation of a person. Kant ascribed to a dualistic view of human agency, and personhood, according to him, was derived from the supersensible capacity for reason. To argue that a Kantian person is generated due to the event of conception ignores Kant's insistence in various aspects of his work that it is not possible to understand the generation of a person qua a physical operation. Finally, I will end the

  6. Optimal weight gain during twin pregnancy in Japanese women with favorable perinatal outcomes.

    Science.gov (United States)

    Suzuki, Shunji

    2018-01-01

    We examined the optimal weight gain in the healthy Japanese women with favorable perinatal outcomes of (dichorionic) twin pregnancy. We calculated the average weight gain in the women whose height was 150-164 cm with favorable perinatal outcomes of dichorionic twin pregnancy set for this study. The women were categorized to underweight, normal, overweight and obese based on the pre-pregnancy body mass index (BMI) categories according to the Institute of Medicine (IOM) and the World Health Organization (WHO) body mass index (BMI) cutoffs. The average GWG in the normal-weight women with the favorable perinatal outcomes was 13.9 ± 3.6 kg. It was significantly different from that in the underweight, overweight and obese women according to the both 2 BMI cutoffs by Student's t-test (p < 0.01). There are optimal ranges of weight gain during twin pregnancy based on the BMI classification.

  7. Uranium favorability of tertiary sedimentary rocks of the Pend Oreille River valley, Washington

    International Nuclear Information System (INIS)

    Marjaniemi, D.K.; Robins, J.W.

    1975-08-01

    Tertiary sedimentary rocks in the Pend Oreille River valley were investigated in a regional study to determine the favorability for potential uranium resources of northeastern Washington. This project involved measurement and sampling of surface sections, collection of samples from isolated outcrops, chemical and mineralogical analyses of samples, and examination of available water well logs. The Box Canyon Dam area north of Ione is judged to have very high favorability. Thick-bedded conglomerates interbedded with sandstones and silty sandstones compose the Tiger Formation in this area, and high radioactivity levels are found near the base of the formation. Uranophane is found along fracture surfaces or in veins. Carbonaceous material is present throughout the Tiger Formation in the area. Part of the broad Pend Oreille valley surrounding Cusick, Washington, is an area of high favorability. Potential host rocks in the Tiger Formation, consisting of arkosic sandstones interbedded with radioactive shales, probably extend throughout the subsurface part of this area. Carbonaceous material is present and some samples contain high concentrations of uranium. In addition, several other possible chemical indicators were found. The Tiger-Lost Creek area is rated as having medium favorability. The Tiger Formation contains very hard, poorly sorted granite conglomerate with some beds of arkosic sandstone and silty sandstone. The granite conglomerate was apparently derived from source rocks having relatively high uranium content. The lower part of the formation is more favorable than the upper part because of the presence of carbonaceous material, anomalously high concentrations of uranium, and other possible chemical indicators. The area west of Ione is judged to have low favorability, because of the very low permeability of the rocks and the very low uranium content

  8. Social-and-economic mechanism of formation of favorable investment attractiveness of the region

    Science.gov (United States)

    Tereshkina, Tatiana; Mottaeva, Angela; Andreeva, Larisa; Larinina, Tatyana

    2017-10-01

    The article is devoted to the matters of investment attractiveness of regions. The factors making the regional investments possible. The authors argue, that social-and-economic development of regions is connected with the formation of the financial mechanism, representing the set of forms and methods of the organization, planning and stimulation of financial-and-economic activity in the certain social-and-economic space. The proper mechanism of formation of favorable investment attractiveness are offered. Besides, the ways of elimination of limiting factors in formation of favorable investment attractiveness are offered.

  9. High procedural fairness heightens the effect of outcome favorability on self-evaluations : An attributional analysis

    NARCIS (Netherlands)

    Brockner, J.; Heuer, L.; Magner, N.; Folger, R.; Umphress, E.; Bos, K. van den; Vermunt, Riël; Magner, M.; Siegel, P.

    2003-01-01

    Previous research has shown that outcome favorability and procedural fairness often interact to influence employees work attitudes and behaviors. Moreover, the form of the interaction effect depends upon the dependent variable. Relative to when procedural fairness is low, high procedural fairness:

  10. Favorable effects of skeletal muscle on bone are distinguished according to gender and skeletal sites

    Directory of Open Access Journals (Sweden)

    Kyoung Min Kim

    2017-03-01

    Conclusions: Higher RASM was significantly associated with lower risk for osteoporosis and the areas at the femur neck and total hip appeared to more likely be affected positively by muscle. Moreover, because males showed faster muscle loss with aging than females, the bones of males may be more prone to favorable effects of muscle.

  11. Uranium favorability of the San Rafael Swell area, east-central Utah

    International Nuclear Information System (INIS)

    Mickle, D.G.; Jones, C.A.; Gallagher, G.L.; Young, P.; Dubyk, W.S.

    1977-10-01

    The San Rafael Swell project area in east-central Utah is approximately 3,000 sq mi and includes the San Rafael Swell anticline and the northern part of the Waterpocket Fold monocline at Capitol Reef. Rocks in the area are predominantly sedimentary rocks of Pennsylvanian through Cretaceous age. Important deposits of uranium in the project area are restricted to two formations, the Chinle (Triassic) and Morrison (Jurassic) Formations. A third formation, the White Rim Sandstone (Permian), was also studied because of reported exploration activity. The White Rim Sandstone is considered generally unfavorable on the basis of lithologic characteristics, distance from a possible source of uranium, lack of apparent mineralization, and the scarcity of anomalies on gamma-ray logs or in rock, water, and stream-sediment samples. The lower Chinle from the Moss Back Member down to the base of the formation is favorable because it is a known producer. New areas for exploration are all subsurface. Both Salt Wash and Brushy Basin Members of the Morrison Formation are favorable. The Salt Wash Member is favorable because it is a known producer. The Brushy Basin Member is favorable as a low-grade resource

  12. Non-take-up of Tax-favored Savings Plans: Are Household Portfolios Optimal?

    NARCIS (Netherlands)

    Alessie, R.J.M.; Hochguertel, Stefan; Soest, van Arthur

    2002-01-01

    Since the early nineties, the Dutch tax system allows for a tax-favored form of risk free savings through employer-sponsored savings plans (ESSPs). Under some conditions and up to a certain amount, the contributions to this plan are tax-deductible, and the returns as well as the withdrawals are

  13. Non-Take-Up of Tax-Favored Savings Plans: Evidence from Dutch Employees

    NARCIS (Netherlands)

    Hochguertel, S.; Alessie, R.J.M.; van Soest, A.

    2006-01-01

    Since the early 1990s, the Dutch tax system allows for a tax-favored form of risk-free savings through employer-sponsored savings plans (ESSPs). Under some conditions and up to a certain amount, the contributions to this plan are tax-deductible, and the returns as well as the withdrawals are

  14. Non-take-up of Tax-favored Savings Plans : Are Household Portfolios Optimal?

    NARCIS (Netherlands)

    Alessie, R.J.M.; Hochgürtel, S.; van Soest, A.H.O.

    2001-01-01

    Since the early nineties, the Dutch tax system allows for a tax-favored form of risk free savings through employer-sponsored savings plans (ESSPs).Under some conditions and up to a certain amount, the contributions to this plan are tax-deductible, and the returns as well as the withdrawals are

  15. Storage of spent fuel: the Senate is favorable to the site of Yucca Mountain

    International Nuclear Information System (INIS)

    Anon.

    1997-01-01

    The Senate commission has approved a law proposition in favor of an intermediate storage destined to receive the spent fuel coming from nuclear power plants and the waste of the Ministry of defense. The chosen site is this one of Yucca Mountain which is already reserved for the long term storage of radioactive waste. (N.C.)

  16. Correlates of Perceived Favorability of Online Courses for Quantitative versus Qualitative Undergraduate Business Majors

    Science.gov (United States)

    Blau, Gary; Pred, Robert; Drennan, Rob B., Jr.; Kapanjie, Darin

    2016-01-01

    An online survey tested the association among background, technological, and course-related variables with perceived favorability of online courses for two independent samples of fall 2015 and spring 2016 business undergraduates taking at least one online or hybrid course. Results showed that perceived learning was a consistent positive correlate…

  17. Does campaign finance imply political favors? The case of the 1998 Brazilian elections

    NARCIS (Netherlands)

    Feijen, E.

    2005-01-01

    This paper provides empirical evidence that campaign contributions are strongly associated with expectations of future firm-specific political favors. Using a novel dataset, we find that during the 1998 elections in Brazil higher campaign contributions to federal deputies were robustly associated

  18. Perceptions of Female and Male Comic Strip Characters II: Favorability and Identification are Different Dimensions.

    Science.gov (United States)

    Potkay, Charles R.; Potkay, Catherine E.

    1984-01-01

    Identification ratings of 20 comic strip characters replicated a prediction that male characters would elicit greater identification, even though previous research showed that female characters are seen in an equivalent or more favorable light than male characters. Significant interaction findings also affirmed a great degree of same sex…

  19. Challenging the Courtesy Bias Interpretation of Favorable Clients' Perceptions of Family Planning Delivery

    Science.gov (United States)

    Len, Federico R.; Lundgren, Rebecka; Huapaya, Ana; Sinai, Irit; Jennings, Victoria

    2007-01-01

    Favorable client perceptions of provider's interpersonal behavior in contraceptive delivery, documented in clinic exit questionnaires, appear to contradict results from qualitative evaluations and are attributed to clients' courtesy bias. In this study, trained simulated clients requested services from Ministry of Health providers in three…

  20. Uranium favorability of the San Rafael Swell area, east-central Utah

    Energy Technology Data Exchange (ETDEWEB)

    Mickle, D G; Jones, C A; Gallagher, G L; Young, P; Dubyk, W S

    1977-10-01

    The San Rafael Swell project area in east-central Utah is approximately 3,000 sq mi and includes the San Rafael Swell anticline and the northern part of the Waterpocket Fold monocline at Capitol Reef. Rocks in the area are predominantly sedimentary rocks of Pennsylvanian through Cretaceous age. Important deposits of uranium in the project area are restricted to two formations, the Chinle (Triassic) and Morrison (Jurassic) Formations. A third formation, the White Rim Sandstone (Permian), was also studied because of reported exploration activity. The White Rim Sandstone is considered generally unfavorable on the basis of lithologic characteristics, distance from a possible source of uranium, lack of apparent mineralization, and the scarcity of anomalies on gamma-ray logs or in rock, water, and stream-sediment samples. The lower Chinle from the Moss Back Member down to the base of the formation is favorable because it is a known producer. New areas for exploration are all subsurface. Both Salt Wash and Brushy Basin Members of the Morrison Formation are favorable. The Salt Wash Member is favorable because it is a known producer. The Brushy Basin Member is favorable as a low-grade resource.

  1. Fibre Optic Sensors Using Adiabatically Tapered Single Mode Fibres

    Science.gov (United States)

    1994-02-01

    Membrane L!2ht Scurce ,ettor ([3Iar~nca] Property ImmobilIzatIon Optical Flba UAnpLl Dynamoc Range SeMfle Su art Arran ramene ,-t n i esuaorn Tlrrm...8217Solution-deposited thin films as passive and active light guides’, Applied Optics, 1972, 11, No 2, pp. 428-34. 397. Urbano , E. , H. Offenbacher, O.S...Chimica Acta, 1988, 208, pp. 53-8. 427. Wolfbeis, O.S., E. Urbano , ’A fluorimetric, heavy-metal-free method for the analysis of chlorine, bromine, and

  2. Interaction of solitary pulses in single mode optical fibres | Usman ...

    African Journals Online (AJOL)

    Two solitary waves launched, by way of incidence, into an optical fibre from a single pulse if the pulses are in-phase as understood from results of inverse scattering transform method applied to the cubic nonlinear Schrödinger equations, (CNLSE\\'s). The single CNLSE is then understood to describe evolution of coupled ...

  3. Single-mode fibre coupler as refractometer sensor

    Indian Academy of Sciences (India)

    indices of reactive acidic solutions whose values matched fairly with the values obtained from the standard refractometer. To check the resolution of the refractometer, two more samples of propylene glycol were prepared by adding pure water. The difference in index of refraction of the samples were maintained at 0.001 RIU ...

  4. Attenuation Coefficient of Single-Mode Periodic Waveguides

    Science.gov (United States)

    Baron, A.; Mazoyer, S.; Smigaj, W.; Lalanne, P.

    2011-10-01

    It is widely accepted that, on ensemble average, the transmission T of guided modes decays exponentially with the waveguide length L due to small imperfections, leading to the important figure of merit defined as the attenuation-rate coefficient α=-⟨ln⁡(T)⟩/L. In this Letter, we evidence that the exponential-damping law is not valid in general for periodic monomode waveguides, especially as the group velocity decreases. This result, that contradicts common beliefs and experimental practices aiming at measuring α, is supported by a theoretical study of light transport in the limit of very small imperfections, and by numerical results obtained for two waveguide geometries that offer contrasted damping behaviors.

  5. Infrared single mode chalcogenide glass fiber for space

    NARCIS (Netherlands)

    Houlzot, P.; Boussard-Plédel, C.; Faber, A.J.; Cheng, L.K.; Bureau, B.; Nijnatten, P.A. van; Gielesen, W.L.M.; Do Carmo, J.P.; Lucas, J.

    2007-01-01

    An important measuring technique under study for the DARWIN planet finding mission, is nulling interferometry, enabling the detection of the weak infrared emission lines of an orbiting planet. This technique requires a perfect wavefront of the light beams to be combined in the interferometer. By

  6. Theoretical Design of a Depolarized Interferometric Fiber-Optic Gyroscope (IFOG on SMF-28 Single-Mode Standard Optical Fiber Based on Closed-Loop Sinusoidal Phase Modulation with Serrodyne Feedback Phase Modulation Using Simulation Tools for Tactical and Industrial Grade Applications

    Directory of Open Access Journals (Sweden)

    Ramón José Pérez

    2016-04-01

    Full Text Available This article presents, by means of computational simulation tools, a full analysis and design of an Interferometric Fiber-Optic Gyroscope (IFOG prototype based on a closed-loop configuration with sinusoidal bias phase- modulation. The complete design of the different blocks, optical and electronic, is presented, including some novelties as the sinusoidal bias phase-modulation and the use of an integrator to generate the serrodyne phase-modulation signal. The paper includes detailed calculation of most parameter values, and the plots of the resulting signals obtained from simulation tools. The design is focused in the use of a standard single-mode optical fiber, allowing a cost competitive implementation compared to commercial IFOG, at the expense of reduced sensitivity. The design contains an IFOG model that accomplishes tactical and industrial grade applications (sensitivity ≤ 0.055 °/h. This design presents two important properties: (1 an optical subsystem with advanced conception: depolarization of the optical wave by means of Lyot depolarizers, which allows to use a sensing coil made by standard optical fiber, instead by polarization maintaining fiber, which supposes consequent cost savings and (2 a novel and simple electronic design that incorporates a linear analog integrator with reset in feedback chain, this integrator generating a serrodyne voltage-wave to apply to Phase-Modulator (PM, so that it will be obtained the interferometric phase cancellation. This particular feedback design with sawtooth-wave generated signal for a closed-loop configuration with sinusoidal bias phase modulation has not been reported till now in the scientific literature and supposes a considerable simplification with regard to previous designs based on similar configurations. The sensing coil consists of an 8 cm average diameter spool that contains 300 m of standard single-mode optical-fiber (SMF-28 type realized by quadrupolar winding. The working

  7. Theoretical Design of a Depolarized Interferometric Fiber-Optic Gyroscope (IFOG) on SMF-28 Single-Mode Standard Optical Fiber Based on Closed-Loop Sinusoidal Phase Modulation with Serrodyne Feedback Phase Modulation Using Simulation Tools for Tactical and Industrial Grade Applications.

    Science.gov (United States)

    Pérez, Ramón José; Álvarez, Ignacio; Enguita, José María

    2016-04-27

    This article presents, by means of computational simulation tools, a full analysis and design of an Interferometric Fiber-Optic Gyroscope (IFOG) prototype based on a closed-loop configuration with sinusoidal bias phase- modulation. The complete design of the different blocks, optical and electronic, is presented, including some novelties as the sinusoidal bias phase-modulation and the use of an integrator to generate the serrodyne phase-modulation signal. The paper includes detailed calculation of most parameter values, and the plots of the resulting signals obtained from simulation tools. The design is focused in the use of a standard single-mode optical fiber, allowing a cost competitive implementation compared to commercial IFOG, at the expense of reduced sensitivity. The design contains an IFOG model that accomplishes tactical and industrial grade applications (sensitivity ≤ 0.055 °/h). This design presents two important properties: (1) an optical subsystem with advanced conception: depolarization of the optical wave by means of Lyot depolarizers, which allows to use a sensing coil made by standard optical fiber, instead by polarization maintaining fiber, which supposes consequent cost savings and (2) a novel and simple electronic design that incorporates a linear analog integrator with reset in feedback chain, this integrator generating a serrodyne voltage-wave to apply to Phase-Modulator (PM), so that it will be obtained the interferometric phase cancellation. This particular feedback design with sawtooth-wave generated signal for a closed-loop configuration with sinusoidal bias phase modulation has not been reported till now in the scientific literature and supposes a considerable simplification with regard to previous designs based on similar configurations. The sensing coil consists of an 8 cm average diameter spool that contains 300 m of standard single-mode optical-fiber (SMF-28 type) realized by quadrupolar winding. The working wavelength will be

  8. Athermal operation of multi-section slotted tunable lasers.

    Science.gov (United States)

    Wallace, M J; O'Reilly Meehan, R; Enright, R; Bello, F; McCloskey, D; Barabadi, B; Wang, E N; Donegan, J F

    2017-06-26

    Two distinct athermal bias current procedures based on thermal tuning are demonstrated for a low-cost, monotlithic, three section slotted single mode laser, achieving mode-hop free wavelength stability of ± 0.04 nm / 5 GHz over a temperature range of 8-47 °C. This is the first time that athermal performance has been demonstrated for a three-section slotted laser with simple fabrication, and is well within the 50 GHz grid spacing specified for DWDM systems. This performance is similar to experiments on more complex DS-DBR lasers, indicating that strong athermal performance can be achieved using our lower-cost three section devices. An analytical model and thermoreflectance measurements provide further insight into the operation of multi-section lasers and lay the foundation for an accurate predictive tool for optimising such devices for athermal operation.

  9. Uranium favorability evaluation of the Mt. Withington cauldron, Socorro County, New Mexico

    International Nuclear Information System (INIS)

    Dickson, R.E.; Dayvault, R.D.

    1982-01-01

    The Mt. Withington cauldron is unfavorable for initial-magmatic pneumatogenic, hydroauthigenic, and hydroallogenic uranium deposits. Despite their favorable major-oxide chemistry, the rocks in the cauldron are relatively poor uranium source rocks; evidence for significant uranium mobilization and transport is lacking; the ash-flow tuffs and the domes and lava flows do not have porous structures adequate to accommodate uranium precipitated by pressure-temperature mechanisms in amounts large enough to constitute uranium deposits; and the lack of reductants signifies that uranium precipitation in adequate amounts by reduction is not probable. It is concluded that no further uranium favorability work in the Mt. Withington cauldron is warranted. 1 figure, 1 table

  10. Cytoskeleton-centric protein transportation by exosomes transforms tumor-favorable macrophages

    Science.gov (United States)

    Cui, Yizhi; Zhou, Yanlong; Yin, Xingfeng; Guo, Jiahui; Zhang, Gong; Wang, Tong; He, Qing-Yu

    2016-01-01

    The exosome is a key initiator of pre-metastatic niche in numerous cancers, where macrophages serve as primary inducers of tumor microenvironment. However, the proteome that can be exosomally transported from cancer cells to macrophages has not been sufficiently characterized so far. Here, we used colorectal cancer (CRC) exosomes to educate tumor-favorable macrophages. With a SILAC-based mass spectrometry strategy, we successfully traced the proteome transported from CRC exosomes to macrophages. Such a proteome primarily focused on promoting cytoskeleton rearrangement, which was biologically validated with multiple cell lines. We reproduced the exosomal transportation of functional vimentin as a proof-of-concept example. In addition, we found that some CRC exosomes could be recognized by macrophages via Fc receptors. Therefore, we revealed the active and necessary role of exosomes secreted from CRC cells to transform cancer-favorable macrophages, with the cytoskeleton-centric proteins serving as the top functional unit. PMID:27602764

  11. Detecting Two-Spirit erotics: The fiction of Carole laFavor.

    Science.gov (United States)

    Tatonetti, Lisa

    2016-01-01

    This article examines the life and novels of Carole laFavor, arguing for her importance to and influence in Two-Spirit studies. Along with being a writer, laFavor was a powerful voice for social justice and Indigenous health sovereignty in Minnesota and the nation. Her two novels, Along the Journey River and Evil Dead Center, which both focus on Anishinaabe lesbian detective protagonist Renee LaRoche, are the first lesbian detective fiction published by a Native author. Renee's embrace of a specifically Two-Spirit erotics anchors her to family and brings her tribal community a powerful healing when she employs her skills to protect her people from instances of racism, abuse, and injustice. This article, then, reads these novels as the first of an emerging genre of texts that claim an overtly Two-Spirit erotic as well as vital precursors to the present embrace of sovereign erotics in Indigenous studies.

  12. Uricase alkaline enzymosomes with enhanced stabilities and anti-hyperuricemia effects induced by favorable microenvironmental changes

    Science.gov (United States)

    Zhou, Yunli; Zhang, Mi; He, Dan; Hu, Xueyuan; Xiong, Huarong; Wu, Jianyong; Zhu, Biyue; Zhang, Jingqing

    2016-01-01

    Enzyme therapy is an effective strategy to treat diseases. Three strategies were pursued to provide the favorable microenvironments for uricase (UCU) to eventually improve its features: using the right type of buffer to constitute the liquid media where catalyze reactions take place; entrapping UCU inside the selectively permeable lipid vesicle membranes; and entrapping catalase together with UCU inside the membranes. The nanosized alkaline enzymosomes containing UCU/(UCU and catalase) (ESU/ESUC) in bicine buffer had better thermal, hypothermal, acid-base and proteolytic stabilities, in vitro and in vivo kinetic characteristics, and uric acid lowering effects. The favorable microenvironments were conducive to the establishment of the enzymosomes with superior properties. It was the first time that two therapeutic enzymes were simultaneously entrapped into one enzymosome having the right type of buffer to achieve added treatment efficacy. The development of ESU/ESUC in bicine buffer provides valuable tactics in hypouricemic therapy and enzymosomal application. PMID:26823332

  13. Cytoskeleton-centric protein transportation by exosomes transforms tumor-favorable macrophages.

    Science.gov (United States)

    Chen, Zhipeng; Yang, Lijuan; Cui, Yizhi; Zhou, Yanlong; Yin, Xingfeng; Guo, Jiahui; Zhang, Gong; Wang, Tong; He, Qing-Yu

    2016-10-11

    The exosome is a key initiator of pre-metastatic niche in numerous cancers, where macrophages serve as primary inducers of tumor microenvironment. However, the proteome that can be exosomally transported from cancer cells to macrophages has not been sufficiently characterized so far. Here, we used colorectal cancer (CRC) exosomes to educate tumor-favorable macrophages. With a SILAC-based mass spectrometry strategy, we successfully traced the proteome transported from CRC exosomes to macrophages. Such a proteome primarily focused on promoting cytoskeleton rearrangement, which was biologically validated with multiple cell lines. We reproduced the exosomal transportation of functional vimentin as a proof-of-concept example. In addition, we found that some CRC exosomes could be recognized by macrophages via Fc receptors. Therefore, we revealed the active and necessary role of exosomes secreted from CRC cells to transform cancer-favorable macrophages, with the cytoskeleton-centric proteins serving as the top functional unit.

  14. Postmating sexual selection favors males that sire offspring with low fitness

    DEFF Research Database (Denmark)

    Bilde, T.; Foged, Anne; Schilling, Nadia

    2009-01-01

    Despite the costs of mating, females of most taxa mate with multiple males. Polyandrous females are hypothesized to gain genetic benefits for their offspring, but this assumes paternity bias favoring male genotypes that enhance offspring viability. We determined net male genetic effects on female...... results imply that sexually antagonistic adaptations have a major and unappreciated influence on male postmating fertilization success. Such genetic variation renders indirect genetic benefits an unlikely driver of the evolution of polyandry....

  15. Misperceiving Bullshit as Profound Is Associated with Favorable Views of Cruz, Rubio, Trump and Conservatism

    Science.gov (United States)

    Pfattheicher, Stefan; Schindler, Simon

    2016-01-01

    The present research investigates the associations between holding favorable views of potential Democratic or Republican candidates for the US presidency 2016 and seeing profoundness in bullshit statements. In this contribution, bullshit is used as a technical term which is defined as communicative expression that lacks content, logic, or truth from the perspective of natural science. We used the Bullshit Receptivity scale (BSR) to measure seeing profoundness in bullshit statements. The BSR scale contains statements that have a correct syntactic structure and seem to be sound and meaningful on first reading but are actually vacuous. Participants (N = 196; obtained via Amazon Mechanical Turk) rated the profoundness of bullshit statements (using the BSR) and provided favorability ratings of three Democratic (Hillary Clinton, Martin O’Malley, and Bernie Sanders) and three Republican candidates for US president (Ted Cruz, Marco Rubio, and Donald Trump). Participants also completed a measure of political liberalism/conservatism. Results revealed that favorable views of all three Republican candidates were positively related to judging bullshit statements as profound. The smallest correlation was found for Donald Trump. Although we observe a positive association between bullshit and support for the three Democrat candidates, this relationship is both substantively small and statistically insignificant. The general measure of political liberalism/conservatism was also related to judging bullshit statements as profound in that individuals who were more politically conservative had a higher tendency to see profoundness in bullshit statements. Of note, these results were not due to a general tendency among conservatives to see profoundness in everything: Favorable views of Republican candidates and conservatism were not significantly related to profoundness ratings of mundane statements. In contrast, this was the case for Hillary Clinton and Martin O’Malley. Overall

  16. Lithofacies paleogeography and favorable gas exploration zones of Qixia and Maokou Fms in the Sichuan Basin

    Directory of Open Access Journals (Sweden)

    Jingao Zhou

    2016-05-01

    Full Text Available In the Sichuan Basin, the Middle Permian marine carbonate rocks are important natural gas pay zones with immense exploration potential, but the facies belts and distribution situations of layered dolomite reservoirs are not clear, which hinders the progress in natural gas exploration. In view of the sedimentary background of the Sichuan Basin, field outcrop section, drilling data and seismic data were comprehensively analyzed with the favorable reservoir intervals in the framework of sequence stratigraphy as the key research units. Research results about its lithofacies paleogeography were obtained as follows. First, a gentle slope SW high and NE low was presented during the sedimentation of the Qixia Fm in the Middle Permian. In the Maokou Fm of the Middle Permian, however, a series of the N–W trending intra-platform rifts were developed in this setting, and eventually a paleogeographic pattern of NE-dipping alternative uplift and depression was evolved. Second, in the Qixia Fm, the transgressive tract was in an open platform environment and the highstand system tract evolved into a rimmed platform. And the platform margin beach in the area of Jiange–Ya'an is the favorable reservoir facies belt. And third, in the Maokou Fm, the transgressive tract was in the carbonate shelf environment and the highstand system tract evolved into a rimmed platform. And the platform margin reef flat in the area of Jiange–Ya'an and the syneclise margin beach in the area of Yanting–Guang'an are favorable reservoir facies belts. It is concluded that the two grain beach facies belts in the areas of Jiange–Ya'an and Yanting–Guang'an were the favorable zones for the large-scale development of Middle Permian layered dolomite reservoirs and they are the main target of subsequent natural gas exploration.

  17. Anti-N-methyl-D-aspartate receptor encephalitis with favorable outcome despite prolonged status epilepticus

    OpenAIRE

    Finné Lenoir, Xavier; Sindic, Christian; Van Pesch, Vincent; El Sankari, Souraya; de Tourtchaninoff, Marianne; Denays, Roger; Hantson, Philippe

    2013-01-01

    BACKGROUND: To describe a case of auto-immune encephalitis in an adolescent with favorable outcome despite prolonged status epilepticus. METHODS: A 17 year old Asian man without previous medical history developed alteration of consciousness and partial seizures. The diagnosis of anti-N-methyl-D-aspartate receptor encephalitis was confirmed by the detection of specific antibodies in both cerebrospinal fluid and serum. RESULTS: The clinical course was complicated by prolonged status epilepticus...

  18. Wide and Fast: Monitoring the Sky in Subsecond Domain with the FAVOR and TORTORA Cameras

    Directory of Open Access Journals (Sweden)

    Sergey Karpov

    2010-01-01

    natural and artificial, it is necessary to perform the systematic monitoring of large regions of the sky with high temporal resolution. Here we discuss the criteria for a system that is able to perform such a task and describe two cameras we created for wide-field monitoring with high temporal resolution—FAVOR and TORTORA. Also, we describe basic principles of real-time data processing for the high frame rates needed to achieve subsecond temporal resolution on a typical hardware.

  19. Misperceiving Bullshit as Profound Is Associated with Favorable Views of Cruz, Rubio, Trump and Conservatism.

    Science.gov (United States)

    Pfattheicher, Stefan; Schindler, Simon

    2016-01-01

    The present research investigates the associations between holding favorable views of potential Democratic or Republican candidates for the US presidency 2016 and seeing profoundness in bullshit statements. In this contribution, bullshit is used as a technical term which is defined as communicative expression that lacks content, logic, or truth from the perspective of natural science. We used the Bullshit Receptivity scale (BSR) to measure seeing profoundness in bullshit statements. The BSR scale contains statements that have a correct syntactic structure and seem to be sound and meaningful on first reading but are actually vacuous. Participants (N = 196; obtained via Amazon Mechanical Turk) rated the profoundness of bullshit statements (using the BSR) and provided favorability ratings of three Democratic (Hillary Clinton, Martin O'Malley, and Bernie Sanders) and three Republican candidates for US president (Ted Cruz, Marco Rubio, and Donald Trump). Participants also completed a measure of political liberalism/conservatism. Results revealed that favorable views of all three Republican candidates were positively related to judging bullshit statements as profound. The smallest correlation was found for Donald Trump. Although we observe a positive association between bullshit and support for the three Democrat candidates, this relationship is both substantively small and statistically insignificant. The general measure of political liberalism/conservatism was also related to judging bullshit statements as profound in that individuals who were more politically conservative had a higher tendency to see profoundness in bullshit statements. Of note, these results were not due to a general tendency among conservatives to see profoundness in everything: Favorable views of Republican candidates and conservatism were not significantly related to profoundness ratings of mundane statements. In contrast, this was the case for Hillary Clinton and Martin O'Malley. Overall, small

  20. Misperceiving Bullshit as Profound Is Associated with Favorable Views of Cruz, Rubio, Trump and Conservatism.

    Directory of Open Access Journals (Sweden)

    Stefan Pfattheicher

    Full Text Available The present research investigates the associations between holding favorable views of potential Democratic or Republican candidates for the US presidency 2016 and seeing profoundness in bullshit statements. In this contribution, bullshit is used as a technical term which is defined as communicative expression that lacks content, logic, or truth from the perspective of natural science. We used the Bullshit Receptivity scale (BSR to measure seeing profoundness in bullshit statements. The BSR scale contains statements that have a correct syntactic structure and seem to be sound and meaningful on first reading but are actually vacuous. Participants (N = 196; obtained via Amazon Mechanical Turk rated the profoundness of bullshit statements (using the BSR and provided favorability ratings of three Democratic (Hillary Clinton, Martin O'Malley, and Bernie Sanders and three Republican candidates for US president (Ted Cruz, Marco Rubio, and Donald Trump. Participants also completed a measure of political liberalism/conservatism. Results revealed that favorable views of all three Republican candidates were positively related to judging bullshit statements as profound. The smallest correlation was found for Donald Trump. Although we observe a positive association between bullshit and support for the three Democrat candidates, this relationship is both substantively small and statistically insignificant. The general measure of political liberalism/conservatism was also related to judging bullshit statements as profound in that individuals who were more politically conservative had a higher tendency to see profoundness in bullshit statements. Of note, these results were not due to a general tendency among conservatives to see profoundness in everything: Favorable views of Republican candidates and conservatism were not significantly related to profoundness ratings of mundane statements. In contrast, this was the case for Hillary Clinton and Martin O

  1. Allozyme marker loci associated with favorable alleles for grain yield in maize.

    Science.gov (United States)

    Mišević, D; Gerić, I; Tadić, B

    1990-10-01

    The evaluation of germplasm to identify its potential as a source of new favorable alleles is a time-consuming phase of maize hybrid breeding programs. The objective of this paper was to study the relationship between allozyme diversity and quantitative estimators of the relative number of new favorable alleles for grain yield, present in donor lines but not present in the elite hybrid. Twenty-two maize inbred lines representing heterotic groups from the United States (US) and Yugoslavia (YU) were used as donors to estimate the presence of new favorable alleles for grain yield improvement for the hybrid B73 x Mo17. In a second experiment, a 15-line diallel was grown, and 13 single crosses differing in allozyme relatedness measure (ARM) and heterotic grouping were considered as targets to be improved by the remaining 13 lines. Minimally biased estimates of new favorable alleles for grain yield (μG) and ARM values were made for all donor lines within each target hybrid. Donor lines were grouped in four allozyme-pedigree classes for each target hybrid to compare the effect of allozyme diversity with pedigree diversity. Pedigree dissimilarities had significant effects on μG estimates. Dissimilar pedigree classes had higher μG estimates than similar pedigree classes. Allozyme differences between donor inbred lines and target hybrids had inconsistent effects on μG estimates. Significant differences in μG estimates among allozyme classes were found for 31% of the target hybrids. Classes with similar allozymes had higher μG estimates more frequently than classes with disimilar allozymes. Correlation coefficients between μG estimates and ARM values were low and not significant for 12 of the 14 target hybrids.

  2. The tax credit in favor of the renewable energies and the energy savings bear fruits

    International Nuclear Information System (INIS)

    2006-01-01

    This document presents in the first part the positive economical results obtained by the implementing in January 2005, of a tax credit majored of 40% in favor of equipments using a renewable energy source. The second part is devoted to other financial incentives in the domain of energy saving and renewable energies uses. Specifications concerning the equipments and legal aspects are presented. (A.L.B.)

  3. Improved DNA Electrophoresis in Conditions Favoring Polyborates and Lewis Acid Complexation

    OpenAIRE

    Singhal, Hari; Ren, Yunzhao R.; Kern, Scott E.

    2010-01-01

    Spatial compression among the longer DNA fragments occurs during DNA electrophoresis in agarose and non-agarose gels when using certain ions in the conductive buffer, impairing the range of fragment sizes resolved well in a single gel. Substitutions using various polyhydroxyl anions supported the underlying phenomenon as the complexation of Lewis acids to DNA. We saw significant improvements using conditions (lithium borate 10 mM cations, pH 6.5) favoring the formation of borate polyanions an...

  4. Renforcement d'un cadre favorable à l'entrepreneuriat en ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Renforcement d'un cadre favorable à l'entrepreneuriat en Cisjordanie et à Gaza. Un chômage élevé, une faible productivité et un secteur privé anémique sont parmi les problèmes économiques auxquels se heurtent la Cisjordanie et Gaza. Favoriser l'entrepreneuriat et l'innovation chez les petites entreprises pourrait ...

  5. Development of a new β Ti alloy with low modulus and favorable plasticity for implant material

    Energy Technology Data Exchange (ETDEWEB)

    Liang, S.X., E-mail: liangshx@hebeu.edu.cn [College of Equipment Manufacture, Hebei University of Engineering, Handan 056038, Hebei (China); Feng, X.J.; Yin, L.X.; Liu, X.Y. [College of Equipment Manufacture, Hebei University of Engineering, Handan 056038, Hebei (China); Ma, M.Z., E-mail: mz550509@ysu.edu.cn [State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004 (China); Liu, R.P. [State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004 (China)

    2016-04-01

    One of the most important development directions of the Ti and its alloys is the applications in medical field. Development of new Ti alloys with low elastic modulus and/or favorable biocompatibility plays an important role for promoting its application in medical field. In this work, a new β Ti alloy (Ti–31Nb–6Zr–5Mo, wt.%) was designed for implant material using d-electron alloy design method. Microstructure and tensile properties of the designed alloy after hot rolling (HR) and solution followed by aging treatments (SA) were investigated. Results show that the designed alloy is composed of single β phase. However, microstructural analysis shows that the β phase in the designed alloy separates into Nb-rich and Nb-poor phase regions. The Nb-rich regions in HR specimen are typical elongated fiber texture, but are equiaxed particles with several micrometers in SA specimen. Tensile results show that the designed alloy has low Young's modulus of 44 GPa for HR specimen and 48 GPa for SA specimen which are very close to the extreme of Young's modulus of bulk titanium alloys. At the same time, the designed alloy has favorable plasticity in term of elongation of 26.7% for HR specimen and 20.6% for SA specimen, and appropriate tensile strength over 700 MPa. In short, the designed alloy has low elastic modulus close to that of bone and favorable plasticity and strength which can be a potential candidate for hard tissue replacements. - Highlights: • A new Ti alloy was designed and prepared using electron alloy design method. • The alloy has low elastic modulus of 44 GPa, favorable plasticity and strength. • The new designed Ti alloy is fully composed of β phase. • Phase separation occurs in the new designed Ti alloy.

  6. [Comparison of the quick Gram stain method to the B&M modified and favor methods].

    Science.gov (United States)

    Osawa, Kayo; Kataoka, Nobumasa; Maruo, Toshio

    2011-01-01

    The Gram stain is an established method for bacterial identification, but the time needed to carry out this stain is 2-3 min. We attempted to shorten this time and stained a total of 70 clinical specimens isolated from using the Bartholomew & Mittwer (B&M) modified or Favor methods with a 3 s duration for washing and staining steps. Results were plotted and analyzed using a Hue Saturation Intensity (HSI) model. The range based on a plot of the two methods with the HSI model was presented as a reference interval. Our results indicated that 100% (35/35) of strains were Gram positive and 97.1% (34/35) were Gram negative for the quick B&M modified method. In the quick Favor method, 80.0% (28/35) were Gram positive and 68.6% (24/35) of strains were Gram negative. We propose that the quick B&M modified method is equivalent to the standard Gram staining method and is superior to the quick Favor method.

  7. Effects of Personality Disorders on Self-Other Agreement and Favorableness in Personality Descriptions.

    Science.gov (United States)

    Tandler, Nancy; Mosch, Alice; Wolf, Annegret; Borkenau, Peter

    2016-10-01

    The authors studied effects of self-reported personality disorder (PD) symptoms on interpersonal perception, particularly self-other agreement and favorableness. Using a round-robin design, 52 groups of four well-acquainted students described themselves and each other on a measure of the Five-Factor model of personality and were administered a self-report screening instrument for DSM-IV (Axis 2). Using the Social Accuracy Model, the peer reports were predicted, across items, from either (a) the target person's self-reports plus the self-report item means, or (b) the items' social desirability. This resulted in separate coefficients for each peer-target dyad, indicating either self-other agreement or favorableness. These coefficients were then predicted from the PD scores of the target and the peer, using multilevel modeling. Main findings were that persons scoring high on PD measures agreed less with their peers on their unique personality characteristics, and that such persons were described by, and described their peers, less favorably.

  8. The Study of Relationship Between Work Teams and Favoring Knowledge Management (Case: Bank Keshavarzi

    Directory of Open Access Journals (Sweden)

    Hamze Jamshidi Kohsari

    2011-03-01

    Full Text Available Knowledge management is a process that has been recently generated as an activity which isvery important in the dynamic environment, and in the competitive scene. We believe that KM is aprocess which its organizational knowledge is created from the individual knowledge of themembers of the organization. The relevant studies have indicated that organizing based on workteams could be considered a way to create the appropriate context for KM. However, thisorganizing based on work teams is not enough; it only has the necessary characteristics of the workteams that favor KM. Moreover, based on studies done, we distinguish which characteristics ofwork teams favor the KM process in its different phases (i.e. creation, transfer and integration. Inthis study, we conducted multiple regression and analysis of variance.Complementary skills (H2 and a climate of trust (H3 in work teams were more importantfactors that favor the management of organizational knowledge.This research is based on the Zarraga and Perez studies in 2006.

  9. Online probabilistic operational safety assessment of multi-mode engineering systems using Bayesian methods

    International Nuclear Information System (INIS)

    Lin, Yufei; Chen, Maoyin; Zhou, Donghua

    2013-01-01

    In the past decades, engineering systems become more and more complex, and generally work at different operational modes. Since incipient fault can lead to dangerous accidents, it is crucial to develop strategies for online operational safety assessment. However, the existing online assessment methods for multi-mode engineering systems commonly assume that samples are independent, which do not hold for practical cases. This paper proposes a probabilistic framework of online operational safety assessment of multi-mode engineering systems with sample dependency. To begin with, a Gaussian mixture model (GMM) is used to characterize multiple operating modes. Then, based on the definition of safety index (SI), the SI for one single mode is calculated. At last, the Bayesian method is presented to calculate the posterior probabilities belonging to each operating mode with sample dependency. The proposed assessment strategy is applied in two examples: one is the aircraft gas turbine, another is an industrial dryer. Both examples illustrate the efficiency of the proposed method

  10. Transcriptomic immunologic signature associated with favorable clinical outcome in basal-like breast tumors.

    Directory of Open Access Journals (Sweden)

    Sandra Martínez-Canales

    Full Text Available Most patients with early stage triple negative breast cancer (TNBC receive adjuvant chemotherapy. Activation of the immune system is associated with tumor response and may help identify TNBC with favorable outcome.Gene expression data were obtained from the GEO Dataset GDS2250/GSE3744. Affymetrix CEL files were downloaded and analyzed with Affymetrix Transcriptome Analysis Console 3.0. Functional genomics was implemented with David Bioinformatics Resources 6.8. Data contained at Oncomine were used to identify genes upregulated in basal-like cancer compared to normal breast tissue. Data contained at cBioportal were used to assess for molecular alterations. The KMPlotter online tool, METABRIC and GSE25066 datasets were used to associate gene signatures with clinical outcome.1564 upregulated genes were identified as differentially expressed between normal and basal-like tumors. Of these, 16 genes associated with immune function were linked with clinical outcome. HLA-C, HLA-F, HLA-G and TIGIT were associated with both improved relapse-free survival (RFS and overall survival (OS. The combination of HLA-F/TIGIT and HLA-C/HLA-F/TIGIT showed the most favorable outcome (HR for RFS 0.44, p<0.001; HR for OS 0.22, p<0.001; and HR for RFS 0.46, p<0.001; HR for OS 0.15, p<0.001; respectively. The association of HLA-C/HLA-F with outcome was confirmed using the METABRIC and GSE25066 datasets. No copy number alterations of these genes were identified.We describe a gene signature associated with immune function and favorable outcome in basal-like breast cancer. Incorporation of this signature in prospective studies may help to stratify risk of early stage TNBC.

  11. Partisan perspectives in the medical literature: a study of high frequency editorialists favoring hormone replacement therapy.

    Science.gov (United States)

    Tatsioni, Athina; Siontis, George C M; Ioannidis, John P A

    2010-09-01

    Unfavorable results of major studies have led to a large shrinkage of the market for hormone replacement therapy (HRT) in the last 6 years. Some scientists continue to strongly support the use of HRT. We analyzed a sample of partisan editorializing articles on HRT to examine their arguments, the reporting of competing interests, the journal venues and their sponsoring societies. Through Thomson ISI database, we selected articles without primary data written by the five most prolific editorialists that addressed clinical topics pertaining to HRT and that were published in regular journal issues in 2002-2008. We recorded the number of articles with a partisan stance and their arguments, the number of partisan articles that reported conflicting interests, and the journal venues and their sponsoring societies publishing the partisan editorials. We analyzed 114 eligible articles (58 editorials, 16 guidelines, 37 reviews, 3 letters), of which 110 (96%) had a partisan stance favoring HRT. Typical arguments were benefits for menopausal and related symptoms (64.9%), criticism of unfavorable studies (78.9%), preclinical data that showed favorable effects of HRT (50%), and benefits for major outcomes such as osteoporosis and fractures (49.1%), cardiovascular disease (31.6%), dementia (24.6%) or colorectal cancer (20.2%), but also even breast cancer (4.4%). All 5 prolific editorialists had financial relationships with hormone manufacturers, but these were reported in only 6 of the 110 partisan articles. Four journals published 15-37 partisan articles each. The medical societies of these journals reported on their websites that several pharmaceutical companies sponsored them or their conferences. There is a considerable body of editorializing articles favoring HRT use and very few of these articles report conflicts of interest. Full disclosure of conflicts of interest is needed, especially for articles without primary data.

  12. Graduate Student Project: Operations Management Product Plan

    Science.gov (United States)

    Fish, Lynn

    2007-01-01

    An operations management product project is an effective instructional technique that fills a void in current operations management literature in product planning. More than 94.1% of 286 graduates favored the project as a learning tool, and results demonstrate the significant impact the project had in predicting student performance. The author…

  13. Some concepts of favorability for world-class-type uranium deposits in the northeastern United States

    Energy Technology Data Exchange (ETDEWEB)

    Adler, H.H.

    1981-03-01

    An account is given of concepts of favorability of geologic environments in the eastern United States for uranium deposits of several major types existing elsewhere in the world. The purpose is to convey some initial ideas about the interrelationships of the geology of the eastern United States and the geologic settings of certain of these world-class deposits. The study and report include consideration of uranium deposits other than those generally manifesting the geologic, geochemical and genetic characteristics associated with the conventional sandstone-type ores of the western United States.

  14. Some concepts of favorability for world-class-type uranium deposits in the northeastern United States

    International Nuclear Information System (INIS)

    Adler, H.H.

    1981-03-01

    An account is given of concepts of favorability of geologic environments in the eastern United States for uranium deposits of several major types existing elsewhere in the world. The purpose is to convey some initial ideas about the interrelationships of the geology of the eastern United States and the geologic settings of certain of these world-class deposits. The study and report include consideration of uranium deposits other than those generally manifesting the geologic, geochemical and genetic characteristics associated with the conventional sandstone-type ores of the western United States

  15. A Favorable Response to Levetiracetam in a Patient with Metastatic Adenoid Cystic Carcinoma.

    Science.gov (United States)

    Sakata, Shinya; Saeki, Sho; Terasaki, Yasuhiro; Natori, Yoshihiro; Fujii, Kazuhiko

    2018-03-01

    Adenoid cystic carcinoma (ACC) is a rare cancer, and there are no standard-of-care treatments for patients with metastatic ACC. We herein report a patient with lung metastasis of ACC who achieved a favorable response to levetiracetam. A 52-year-old Japanese man was admitted to our hospital because of multiple lung metastases of ACC. We performed first-line chemotherapy with cisplatin plus gemcitabine, and subsequently oral S-1 as second-line chemotherapy, which resulted in disease progression. The patient developed symptomatic epilepsy and received levetiracetam (250 mg twice daily). At five months after the initiation of levetiracetam, chest computed tomography showed regression of the metastatic lung lesions.

  16. Population synthesis analysis: determining parameters and favorable scenarios for the formation of Solar System Analogs

    Science.gov (United States)

    Ronco, M. P.; Gulera, O. M.; de Elía, G. C.

    2017-07-01

    The primordial scenario and the initial conditions that gave rise to the Solar System are still under debate. A population synthesis analysis of the formation and evolution of Solar System Analogs (SSA) is a possible mechanism to understand our own Solar System. From a new numerical code called PlanetaLP, which is able to build a diversity of planetary systems describing the evolution of embryos and planetesimals during the gaseous phase, we determine which are the parameters of the disk and the most favorable scenarios that provide planetary systems like our own.

  17. IMPACT OF ISLAMIC RELIGIOUS SYMBOL IN PRODUCING FAVORABLE ATTITUDE TOWARD ADVERTISEMENT

    Directory of Open Access Journals (Sweden)

    Abbas NASERI

    2012-06-01

    Full Text Available A review of the literature on religion and advertisement led to the identification of three lines of studies examining the influence of religion on advertising. These three lines of studies focused on attitude toward advertising of controversial products, presence of religious values in advertisements executions, and the consumers’ reactions to advertisement containing religious cues or symbols. The latter line has been followed modestly in Christian context but not in Islamic context of advertising. Hijab as a significant religious cue might peripherally generates a favorable attitude toward advertisement among Muslims. It is suggested that information processing theories like Elaboration Likelihood Model provides a pertinent theoretical framework to examine this effect empirically.

  18. Artroplastía de superficie en cadera. Resultados iniciales favorables en pacientes selectos. [Hip resurfacing arthroplasty: favorable initial results in selected patients

    Directory of Open Access Journals (Sweden)

    Fernando Martín Comba

    2013-12-01

    Full Text Available In­tro­duc­ción El objetivo del presente trabajo es reportar los resultados clínicos y radiológicos iniciales de una serie consecutiva de pacientes selectos tratados en nuestra institución con un único diseño de artroplastia de superficie, comparando además la tasa de revisión temprana con un grupo control de pacientes tratados en el mismo lapso con una artroplastia total de cadera no cementada. Material y ­Métodos Cuarenta y siete pacientes de sexo masculino (49 caderas con diagnóstico de artrosis de cadera que fueron tratados quirúrgicamente con una artroplastia híbrida de superficie, entre noviembre de 2006 y julio de 2009. La edad promedio fue de 44,5 años (rango de 21 a 57. En todos los casos, la indicación de la artroplastia de superficie se realizó en pacientes jóvenes con alta expectativa funcional y siguiendo estrictos criterios de selección radiológicos. Se efectuó un seguimiento clínico y un meticuloso análisis radiológico. Resultados La escala funcional posoperatoria de Merle D’Aubigné-Postel fue, en promedio, de 17,3 puntos a los 43 meses de seguimiento promedio (rango 24-62 meses. El 85% de los pacientes refirió que practicaba alguna actividad deportiva con una escala UCLA promedio de 9,5 (rango 8-10. Un paciente requirió una cirugía de revisión (2,04% por fractura de cuello femoral. No existieron diferencias estadísticamente significativas en cuanto a la tasa de revisión temprana comparando con el grupo control (p = 0,55. Conclusiones En nuestra experiencia inicial con artroplastia de superficie, obtuvimos resultados a corto plazo favorables, en una serie de hombres con artrosis y alta demanda funcional, estrictamente seleccionados.

  19. Are meteorological conditions favoring hail precipitation change in Southern Europe? Analysis of the period 1948-2015

    Science.gov (United States)

    Sanchez, J. L.; Merino, A.; Melcón, P.; García-Ortega, E.; Fernández-González, S.; Berthet, C.; Dessens, J.

    2017-12-01

    In the context of a warming climate, one of the variables currently under investigation is related to the detection of possible changes in hail precipitation. In this work, we analyze hail frequencies in one of the most affected areas by this phenomenon in Europe, southern France. Here, an extensive hail detection network has been in operation since 1988. In general, the detection of hailfall is very uncertain. To overcome the constraints of scarcity and poor standardization of hail detection and monitoring systems, some relationships between hailstorm occurrence and synoptic, mesoscale or thermodynamic atmospheric characteristics have been proposed in different areas. Therefore, we analyzed meteorological fields at synoptic scale that are related to the formation of hailstorms in the study area, i.e., geopotential height at 500 hPa, sea level pressure, and lapse-rate between 850 and 500 hPa. These fields describe the state of the atmosphere at low and mid levels, and facilitate the evaluation of thermal and dynamic instability. Using the Mann-Kendall test and Sen estimator, we examined trends in the three fields during the period 1948-2015 and their spatial patterns, revealing an evolution toward synoptic environments that favor hail precipitation in the Mediterranean region.

  20. [Who is against prevention? A map of policy actors favoring smoking in Spain].

    Science.gov (United States)

    Granero, Lluís; Villalbí, Joan Ramón; Gallego, Raquel

    2004-01-01

    For a comprehensive approach to policies on smoking, the map of actors related to tobacco and their political ties needs to be identified. The present article constitutes the first attempt at this task in Spain. Analysis of the press, industry publications, and interviews with key people. Active actors favoring smoking in Spain were identified and classified according to their characteristics, the sphere in which they act, and their preferred territorial arena. We identified tobacco companies (Altadis and Philip Morris dominate the market), tobacco trade organizations (tobacconists), front-line organizations created by the tobacco industry (The Smokers for Tolerance Club), organizations of tobacco growers, and processing companies. Distribution to retailers is dominated by Logista, owned by Altadis. Other sectors to take into account are vending companies and those manufacturing related products (cigarette paper, matches or lighters). The contacts of these actors with the public administration are reviewed, notable among which are the role of the Commissioner for the Tobacco Market, the Ministry of Agriculture, the Ministry of Finance and the Ministry of the Economy. Ties were also found with employers' organizations, some political parties, and unions, as well as with other sectors with social influence such as the media and advertising sectors. The map of actors favoring smoking in Spain is complex and goes beyond the confines of the tobacco industry. Understanding this web is crucial to promoting comprehensive prevention policies.

  1. Spatial heterogeneity in human activities favors the persistence of wolves in agroecosystems.

    Science.gov (United States)

    Ahmadi, Mohsen; López-Bao, José Vicente; Kaboli, Mohammad

    2014-01-01

    As human populations expand, there is increasing demand and pressure for land. Under this scenario, behavioural flexibility and adaptation become important processes leading to the persistence of large carnivores in human-dominated landscapes such as agroecosystems. A growing interest has recently emerged on the outcome of the coexistence between wolves and humans in these systems. It has been suggested that spatial heterogeneity in human activities would be a major environmental factor modulating vulnerability and persistence of this contentious species in agroecosystems. Here, we combined information from 35 den sites detected between 2011 and 2012 in agroecosystems of western Iran (Hamedan province), a set of environmental variables measured at landscape and fine spatial scales, and generalized linear models to identify patterns of den site selection by wolves in a highly-modified agroecosystem. On a landscape level, wolves selected a mixture of rangelands with scattered dry-farms on hillsides (showing a low human use) to locate their dens, avoiding areas with high densities of settlements and primary roads. On a fine spatial scale, wolves primarily excavated dens into the sides of elevated steep-slope hills with availability of water bodies in the vicinity of den sites, and wolves were relegated to dig in places with coarse-soil particles. Our results suggest that vulnerability of wolves in human-dominated landscapes could be compensated by the existence of spatial heterogeneity in human activities. Such heterogeneity would favor wolf persistence in agroecosystems favoring a land sharing model of coexistence between wolves and people.

  2. Resource allocation in offspring provisioning: an evaluation of the conditions favoring the evolution of matrotrophy.

    Science.gov (United States)

    Trexler, Joel C; DeAngelis, Donald L

    2003-11-01

    We used analytic and simulation models to determine the ecological conditions favoring evolution of a matrotrophic fish from a lecithotrophic ancestor given a complex set of trade-offs. Matrotrophy is the nourishment of viviparous embryos by resources provided between fertilization and parturition, while lecithotrophy describes embryo nourishment provided before fertilization. In fishes and reptiles, embryo nourishment encompasses a continuum from solely lecithotrophic to primarily matrotrophic. Matrotrophy has evolved independently from lecithotrophic ancestors many times in many groups. We assumed matrotrophy increased the number of offspring a viviparous female could gestate and evaluated conditions of food availability favoring lecithotrophy or matrotrophy. The matrotrophic strategy was superior when food resources exceeded demand during gestation but at a risk of overproduction and reproductive failure if food intake was limited. Matrotrophic females were leaner during gestation than lecithotrophic females, yielding shorter life spans. Our models suggest that matrotrophic embryo nourishment evolved in environments with high food availability, consistently exceeding energy requirements for maintaining relatively large broods. Embryo abortion with some resorption of invested energy is a necessary preadaptation to the evolution of matrotrophy. Future work should explore trade-offs of age-specific mortality and reproductive output for females maintaining different levels of fat storage during gestation.

  3. CD73 Predicts Favorable Prognosis in Patients with Nonmuscle-Invasive Urothelial Bladder Cancer

    Directory of Open Access Journals (Sweden)

    Marian S. Wettstein

    2015-01-01

    Full Text Available Aims. CD73 is a membrane associated 5′-ectonucleotidase that has been proposed as prognostic biomarker in various solid tumors. The aim of this study is to evaluate CD73 expression in a cohort of patients with primary bladder cancer in regard to its association with clinicopathological features and disease course. Methods. Tissue samples from 174 patients with a primary urothelial carcinoma were immunohistochemically assessed on a tissue microarray. Associations between CD73 expression and retrospectively obtained clinicopathological data were evaluated by contingency analysis. Survival analysis was performed to investigate the predictive value of CD73 within the subgroup of pTa and pT1 tumors in regard to progression-free survival (PFS. Results. High CD73 expression was found in 46 (26.4% patients and was significantly associated with lower stage, lower grade, less adjacent carcinoma in situ and with lower Ki-67 proliferation index. High CD73 immunoreactivity in the subgroup of pTa and pT1 tumors (n=158 was significantly associated with longer PFS (HR: 0.228; p=0.047 in univariable Cox regression analysis. Conclusion. High CD73 immunoreactivity was associated with favorable clinicopathological features. Furthermore, it predicts better outcome in the subgroup of pTa and pT1 tumors and may thus serve as additional tool for the selection of patients with favorable prognosis.

  4. Does Spontaneous Favorability to Power (vs. Universalism) Values Predict Spontaneous Prejudice and Discrimination?

    Science.gov (United States)

    Souchon, Nicolas; Maio, Gregory R; Hanel, Paul H P; Bardin, Brigitte

    2017-10-01

    We conducted five studies testing whether an implicit measure of favorability toward power over universalism values predicts spontaneous prejudice and discrimination. Studies 1 (N = 192) and 2 (N = 86) examined correlations between spontaneous favorability toward power (vs. universalism) values, achievement (vs. benevolence) values, and a spontaneous measure of prejudice toward ethnic minorities. Study 3 (N = 159) tested whether conditioning participants to associate power values with positive adjectives and universalism values with negative adjectives (or inversely) affects spontaneous prejudice. Study 4 (N = 95) tested whether decision bias toward female handball players could be predicted by spontaneous attitude toward power (vs. universalism) values. Study 5 (N = 123) examined correlations between spontaneous attitude toward power (vs. universalism) values, spontaneous importance toward power (vs. universalism) values, and spontaneous prejudice toward Black African people. Spontaneous positivity toward power (vs. universalism) values was associated with spontaneous negativity toward minorities and predicted gender bias in a decision task, whereas the explicit measures did not. These results indicate that the implicit assessment of evaluative responses attached to human values helps to model value-attitude-behavior relations. © 2016 The Authors. Journal of Personality Published by Wiley Periodicals, Inc.

  5. Role of Green Spaces in Favorable Microclimate Creating in Urban Environment (Exemplified by Italian Cities)

    Science.gov (United States)

    Finaeva, O.

    2017-11-01

    The article represents a brief analysis of factors that influence the development of an urban green space system: territorial and climatic conditions, cultural and historical background as well as the modern strategy of historic cities development. The introduction defines the concept of urban greening, green spaces and green space distribution. The environmental parameters influenced by green spaces are determined. By the example of Italian cities the principles of the urban greening system development are considered: the historical aspects of formation of the urban greening system in Italian cities are analyzed, the role of green spaces in the formation of the urban environment structure and the creation of a favorable microclimate is determined, and a set of measures aimed at its improvement is highlighted. The modern principles of urban greening systems development and their characteristic features are considered. Special attention is paid to the interrelation of architectural and green structures in the formation of a favorable microclimate and psychological comfort in the urban environment; various methods of greening are considered by the example of existing architectural complexes depending on the climate of the area and the landscape features. The examples for the choice of plants and the application of compositional techniques are given. The results represent the basic principles of developing an urban green spaces system. The conclusion summarizes the techniques aimed at the microclimate improvement in the urban environment.

  6. Treatment of hyperphosphatemia, secondary hyperparathyroidism and hypocalcemia with calcium carbonate favorably modulates vaccination response in uremic rats.

    Science.gov (United States)

    Hannula, P M; Pörsti, I H; Saha, H H T; Kalliovalkama, J; Jolma, P M; Kööbi, P; Olander, R M; Antonen, J A

    2004-06-01

    Immune dysfunction is characteristic of renal failure, leading to suboptimal antibody generation and increased susceptibility to infections. We tested whether the treatment of uremic phosphate retention by increased calcium carbonate intake will beneficially influence vaccination response in 5/6-nephrectomized rats. The nephrectomized (uremic) and sham-operated (control) rats were either fed 0.3% calcium diet (NTX and Sham groups, respectively) or 3% high-calcium diet (Ca-NTX and Ca-Sham groups). All rats were immunized with tetanus toxoid 6 weeks after the operations, and antitoxin levels were measured 7 weeks later. Plasma creatinine was significantly elevated after the nephrectomy: the values (mean +/- SD) in the NTX (n = 16), Ca-NTX (n = 11), Sham (n = 14) and Ca-Sham (n = 8) groups were 97 +/- 14, 93 +/- 17, 66 +/- 7, and 69 +/- 8 micromol/l, respectively. The NTX group developed phosphate retention and secondary hyperparathyroidism, which were completely prevented by the high calcium diet. The mean tetanus antitoxin concentrations of the groups were: NTX 0.25 +/- 0.32; Ca-NTX 0.45 +/- 0.44; Sham 0.58 +/- 0.24 and Ca-Sham 0.64 +/- 0.25 IU/ml (log of geometric mean concentration). The antibody response in the NTX group was significantly lower, i.e. 43% of that in the Sham group (p = 0.003), while the response in the Ca-NTX group was not different from that in the Sham group. The tetanus response of all the uremic rats inversely correlated with the plasma levels of phosphate (r = 0.447, p = 0.02), parathormone (r = -0.409, p = 0.03) and creatinine (r = 0.578, p = 0.002). We conclude that renal failure impairs vaccination response in rats, the impairment of which can be favorably modulated by phosphate-binding and PTH-suppressing high-calcium diet.

  7. High power, low divergent, substrate emitting quantum cascade ring laser in continuous wave operation

    Directory of Open Access Journals (Sweden)

    D. H. Wu

    2017-03-01

    Full Text Available We demonstrate a surface grating coupled substrate emitting quantum cascade ring laser with high power room temperature continuous wave operation at 4.64 μm. A second order surface metal/semiconductor distributed-feedback grating is used for in-plane feedback and vertical out-coupling. A device with 400 μm radius ring cavity exhibits an output power of 202 mW in room temperature continuous wave operation. Single mode operation with a side mode suppression ratio of 25 dB is obtained along with a good linear tuning with temperature. The far field measurement exhibits a low divergent concentric ring beam pattern with a lobe separation of ∼0.34°, which indicates that the device operates in fundamental mode (n = 1.

  8. 8 CFR 316.11 - Attachment to the Constitution; favorable disposition towards the good order and happiness.

    Science.gov (United States)

    2010-01-01

    ... disposition towards the good order and happiness. 316.11 Section 316.11 Aliens and Nationality DEPARTMENT OF... the Constitution; favorable disposition towards the good order and happiness. (a) General. An... favorably disposed toward the good order and happiness of the United States. Attachment implies a depth of...

  9. Remotely Operated Vehicle “ROV KIEL 6000“

    Directory of Open Access Journals (Sweden)

    Friedrich Abegg

    2017-08-01

    Full Text Available The remotely operated vehicle ROV KIEL 6000 is a deep diving platform rated for water depths of 6000 meters. It is linked to a surface vessel via an umbilical cable transmitting power (copper wires and data (3 single-mode glass fibers. As standard it comes equipped with still and video cameras and two different manipulators providing eyes and hands in the deep. Besides this a set of other tools may be added depending on the mission tasks, ranging from simple manipulative tools such as chisels and shovels to electrically connected instruments which can send in-situ data to the ship through the ROVs network, allowing immediate decisions upon manipulation or sampling strategies.

  10. Determination of the Optimal Cutoff Values for Pain Sensitivity Questionnaire Scores and the Oswestry Disability Index for Favorable Surgical Outcomes in Subjects With Lumbar Spinal Stenosis.

    Science.gov (United States)

    Kim, Ho-Joong; Park, Jong-Woong; Kang, Kyoung-Tak; Chang, Bong-Soon; Lee, Choon-Ki; Kang, Sung-Shik; Yeom, Jin S

    2015-10-15

    Retrospective analysis of prospectively collected data (NCT02134821). The aim of this study was to elucidate the cutoff values for significant predictors for favorable outcomes after lumbar spine surgery in patients with lumbar spinal stenosis (LSS). Various factors are associated with the surgical outcomes for patients with LSS. However, we did not know the odds ratio and/or cutoff values of a predictive factor for a favorable surgical outcome for LSS. A total of 157 patients who underwent spine surgery due to LSS between June 2012 and April 2013 were included in this study. The patients were dichotomized into 2 groups on the basis of an Oswestry Disability Index (ODI) score of 22 or less (favorable outcome group) or more than 22 (unfavorable outcome group) at 12 months after surgery. Regarding favorable outcomes, the odds ratio for each preoperative variable including demographic data, preoperative symptom severity, and pain sensitivity questionnaire (PSQ) score was calculated using univariate and multivariate logistic regression analyses. For the significant variables for surgical outcome, receiver operating characteristic (ROC) curve was plotted with calculation of the area under the ROC curve. Multivariate analysis revealed that the ODI and total PSQ scores were significantly associated with a greater likelihood of an unfavorable surgical outcome [odds ratio (95% confidence interval) of ODI, 1.289 (1.028-1.616); odds ratio (95% confidence interval) of total PSQ, 1.060 (1.009-1.113)]. ROC analysis revealed area under the ROC curves for the total PSQ and ODI scores of 0.638 (P = 0.005) and 0.692 (P disability and pain sensitivity can be predictors of the functional level achieved after spine surgery in patients with LSS, and the ideal cutoff values for the total PSQ and ODI scores were 6.6 and 45.0, respectively.

  11. Alcances y dimensiones del plagio en la narrativa de Alberto Laiseca: alrededor de Por favor ¡plágienme!

    Directory of Open Access Journals (Sweden)

    Carlos Fernández González

    2014-11-01

    Full Text Available A través de la lectura crítica de Por Favor ¡Plágienme! (1991, texto clave para la comprensión del universo estético y creativo de Alberto Laiseca, este artículo plantea reflexiones sobre el enfoque singular que su obra narrativa aporta al problema del plagio en la literatura contemporánea y postula, al mismo tiempo, la posibilidad de pensar la obra de Laiseca en tensa –y paródica– relación con la tradición literaria argentina y su canon. Esta lectura permitirá operar críticamente sobre el dispositivo central de la literatura laisecana, que consiste en desestabilizar los discursos teóricos disponibles sobre aspectos aplicables a su poética, como el del horizonte conceptual del plagio. Desde aquí se volverá posible pensar en los motivos por los cuales una crítica literaria hegemónica tiene hasta el momento poco diálogo con la obra de quien es, sin embargo, uno de los autores contemporáneos más prolíficos de la literatura argentina. Through the critical reading of Por Favor ¡Plágienme! (1991, a key text for understanding the aesthetic and creative universe of Alberto Laiseca, this article enquires into the unique approach that his narrative opens to the issue of plagiarism in contemporary literature. The article also postulates thinking Laiseca’s work in a tense –and parodic– relationship with the Argentinian literary tradition and its canon. This reading will operate on the central device of “Laisecan” literature, which consists on destabilizing available theoretical discourses over aspects that can be applied to his poetics, as the conceptual horizon of plagiarism. From here it will be possible to consider why a hegemonic literary criticism has had little dialogue with the work of someone who is, however, one of the most prolific contemporary writers of Argentinian literature.

  12. Some effects of favorable and adverse electric fields on pool boiling in dielectric fluids

    International Nuclear Information System (INIS)

    Masson, Viviana

    2001-01-01

    The effects of the application of an electric field on pool boiling in dielectric fluids were studied in this work.Two different geometries were used: one which is favorable to the bubble detachment (favorable electric field) and other which attract the bubbles toward the heater (adverse electric field).In the favorable electric field experiments, the void fraction and impact rate were calculated from the measured indicator function.Those parameters were obtained varying the probe-heater distance and the power to the heater.The results show a reduction of the void fraction with increasing applied voltage, probably caused by the combination of the dielectrophoretic force and a smaller bubble size due to the electric field application. Also, the impact rate decreases when a voltage is applied and the heat fluxes are close to the critical heat flux (CHF).On the other hand, the impact rate increases with voltage for moderate heat fluxes.Another interesting result is the approximately exponential decay of the void fraction and impact rate with the distance to the heater. Both the void fraction and the impact rate grow with heat flux if the heat fluxes are moderate, with or without applied voltage.For highest heat fluxes the void fraction still grows with heat flux if there are no applied electric fields while decreases with heat flux when there is an applied voltage. Similar behavior is observed in the impact rate.The boiling regimes was measured with adverse electric fields using two techniques.The heat transfer in the nucleate boiling regime was measured on an electrically powered heater.The results in these experiments show a reduction in the CHF of 10 % for saturation conditions and 10 kV of applied voltage, and a reduction of up to 40 % for 20 oC of liquid subcooling.The boiling curve corresponding to the transition and film boiling was performed with quenching experiments.An increase in the heat flux was achieved when an electric field was applied in spite of the

  13. Multivariate statistical analysis to investigate the subduction zone parameters favoring the occurrence of giant megathrust earthquakes

    Science.gov (United States)

    Brizzi, S.; Sandri, L.; Funiciello, F.; Corbi, F.; Piromallo, C.; Heuret, A.

    2018-03-01

    The observed maximum magnitude of subduction megathrust earthquakes is highly variable worldwide. One key question is which conditions, if any, favor the occurrence of giant earthquakes (Mw ≥ 8.5). Here we carry out a multivariate statistical study in order to investigate the factors affecting the maximum magnitude of subduction megathrust earthquakes. We find that the trench-parallel extent of subduction zones and the thickness of trench sediments provide the largest discriminating capability between subduction zones that have experienced giant earthquakes and those having significantly lower maximum magnitude. Monte Carlo simulations show that the observed spatial distribution of giant earthquakes cannot be explained by pure chance to a statistically significant level. We suggest that the combination of a long subduction zone with thick trench sediments likely promotes a great lateral rupture propagation, characteristic of almost all giant earthquakes.

  14. Cosmology favoring extra radiation and sub-eV mass sterile neutrinos as an option.

    Science.gov (United States)

    Hamann, Jan; Hannestad, Steen; Raffelt, Georg G; Tamborra, Irene; Wong, Yvonne Y Y

    2010-10-29

    Precision cosmology and big-bang nucleosynthesis mildly favor extra radiation in the Universe beyond photons and ordinary neutrinos, lending support to the existence of low-mass sterile neutrinos. We use the WMAP 7-year data, small-scale cosmic microwave background observations from ACBAR, BICEP, and QuAD, the SDSS 7th data release, and measurement of the Hubble parameter from HST observations to derive credible regions for the assumed common mass scale m{s} and effective number N{s} of thermally excited sterile neutrino states. Our results are compatible with the existence of one or perhaps two sterile neutrinos, as suggested by LSND and MiniBooNE, if m{s} is in the sub-eV range.

  15. Improved DNA electrophoresis in conditions favoring polyborates and lewis acid complexation.

    Directory of Open Access Journals (Sweden)

    Hari Singhal

    2010-06-01

    Full Text Available Spatial compression among the longer DNA fragments occurs during DNA electrophoresis in agarose and non-agarose gels when using certain ions in the conductive buffer, impairing the range of fragment sizes resolved well in a single gel. Substitutions using various polyhydroxyl anions supported the underlying phenomenon as the complexation of Lewis acids to DNA. We saw significant improvements using conditions (lithium borate 10 mM cations, pH 6.5 favoring the formation of borate polyanions and having lower conductance and Joule heating, delayed electrolyte exhaustion, faster electrophoretic run-speed, and sharper separation of DNA bands from 100 bp to 12 kb in a single run.

  16. The experience of freedom in decisions - Questioning philosophical beliefs in favor of psychological determinants.

    Science.gov (United States)

    Lau, Stephan; Hiemisch, Anette; Baumeister, Roy F

    2015-05-01

    Six experiments tested two competing models of subjective freedom during decision-making. The process model is mainly based on philosophical conceptions of free will and assumes that features of the process of choosing affect subjective feelings of freedom. In contrast, the outcome model predicts that subjective freedom is due to positive outcomes that can be expected or are achieved by a decision. Results heavily favored the outcome model over the process model. For example, participants felt freer when choosing between two equally good than two equally bad options. Process features including number of options, complexity of decision, uncertainty, having the option to defer the decision, conflict among reasons, and investing high effort in choosing generally had no or even negative effects on subjective freedom. In contrast, participants reported high freedom with good outcomes and low freedom with bad outcomes, and ease of deciding increased subjective freedom, consistent with the outcome model. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Prejudice, Social Dominance, and Similarity among People who Favor Integration of Minorities.

    Science.gov (United States)

    Martínez, Carmen; Saiz, José; Angosto, Josefa

    2016-04-12

    This study examines differences in prejudice, perceived similarity, and social dominance in members of the majority who favor integration as a means of minority acculturation. A total of 342 non-Gypsy Spanish participants filled out a questionnaire about their relationship to one of three outgroups: Maghrebians, Gypsies, and Latin Americans. Hierarchical cluster analysis showed that a three-cluster solution was most fitting for every outgroup. ANOVAs applied to the three clusters indicated significant differences in prejudice, perceived similarity, and social dominance. Referring to Gypsies the largest effect size was observed in manifest prejudice (η2 = .63), in Maghrebians, the largest effect size was observed in subtle prejudice (η2 =.77), while for Latin Americans, perceived similarity had the largest effect size η2 ( = .60). The results reveal a need to modify existing measures of integration; we recommend using questionnaires to measure behaviors that members of the majority would be willing to implement.

  18. Subcellular location of astrocytic calcium stores favors extrasynaptic neuron-astrocyte communication.

    Science.gov (United States)

    Patrushev, Ilya; Gavrilov, Nikolay; Turlapov, Vadim; Semyanov, Alexey

    2013-11-01

    Neuron-astrocyte interactions are important for brain computations and synaptic plasticity. Perisynaptic astrocytic processes (PAPs) contain a high density of transporters that are responsible for neurotransmitter clearance. Metabotropic glutamate receptors are thought to trigger Ca(2+) release from Ca(2+) stores in PAPs in response to synaptic activity. Our ultrastructural study revealed that PAPs are actually devoid of Ca(2+) stores and have a high surface-to-volume ratio favorable for uptake. Astrocytic processes containing Ca(2+) stores were located further away from the synapses and could therefore respond to changes in ambient glutamate. Thus, the anatomic data do not support communication involving Ca(2+) stores in tripartite synapses, but rather point to extrasynaptic communication. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Maternal Acceptance: Its Contribution to Children's Favorable Perceptions of Discipline and Moral Identity.

    Science.gov (United States)

    Patrick, Renee B; Gibbs, John C

    2016-01-01

    The authors examined the contribution of maternal acceptance or warmth to children's and adolescents' perceptions of discipline and formation of moral identity. The sample consisted of 93 male and female students from Grades 5, 8, and 10 and their mothers. Students completed measures pertaining to perceived maternal discipline practices and acceptance-rejection, as well as moral identity. A subsample of mothers reported on their accepting or rejecting actions toward their children. Children were more likely to feel accepted, if their mothers used inductive discipline (vs. power assertion and love withdrawal). Perceived acceptance was also related to more favorable discipline evaluations in certain respects. Specifically, inductive discipline recipients who felt accepted also evaluated induction as appropriate and responded to it with positive and guilt-related emotions. Power assertion was evaluated as appropriate among those children who did feel accepted. Finally, among inductive discipline recipients, those who felt accepted also reported higher moral identity.

  20. Is there a Relationship between Patient Satisfaction and Favorable Surgical Outcomes?

    Science.gov (United States)

    Tevis, Sarah E.; Kennedy, Gregory D.; Kent, K. Craig

    2015-01-01

    Summary Satisfaction of patients with their health care is gaining importance as a measure of hospital quality due to public reporting of these values and an increasing connection between hospital reimbursement and scores on the current tool to measure satisfaction, the Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) survey. We found that high hospital and surgical volume and low rates of risk-adjusted mortality are associated with high patient satisfaction. However, other favorable patient outcomes are not consistently associated with positive satisfaction scores on HCAHPS. Contributors to patients' perceptions of their care are likely multifactorial and not related just to outcomes traditionally assessed by surgeons or hospitals. Moving in a direction of patient centered care, with a focus on increased understanding and involvement of patients in the care process, will likely strengthen the relationship between surgical outcomes and patient satisfaction. PMID:26299501

  1. Superstition predicts favorable weight change in an open-placebo trial: a prospective study.

    Science.gov (United States)

    Rekhviashvili, Nino; Gupta, Sumati

    2015-09-01

    Given the difficulty of losing weight via adhering to healthy lifestyle choices, this study sought to understand how a placebo may elicit favorable weight change. Specifically, we examined if superstition may be related to increased responsiveness to an open-placebo. In this pilot study of 25 undergraduate participants, it was hypothesized that individuals with higher levels of superstition may be more responsive to a 3-week open-placebo weight change trial. Participants were given once-daily saltine crackers to use as open-placebos for weight change in their preferred direction (gain or loss). The weight of each participant was measured before and after the 3-week open-placebo period. A Pearson's r correlation showed a significant positive relationship between superstition and placebo responsiveness, determined by weight gain or loss in the preferred direction, r (25) = 0.493, p placebo uses for weight management.

  2. Tunable Degradation Rate and Favorable Bioactivity of Porous Calcium Sulfate Scaffolds by Introducing Nano-Hydroxyapatite

    Directory of Open Access Journals (Sweden)

    Jianhua Zhou

    2016-12-01

    Full Text Available The bone scaffolds should possess suitable physicochemical properties and osteogenic activities. In this study, porous calcium sulfate (CaSO4 scaffolds were fabricated successfully via selected laser sintering (SLS. Nano-hydroxyapatite (nHAp, a bioactive material with a low degradation rate, was introduced into CaSO4 scaffolds to overcome the overquick absorption. The results demonstrated that nHAp could not only control the degradation rate of scaffolds by adjusting their content, but also improve the pH environment by alleviating the acidification progress during the degradation of CaSO4 scaffolds. Moreover, the improved scaffolds were covered completely with the apatite spherulites in simulated body fluid (SBF, showing their favorable bioactivity. In addition, the compression strength and fracture toughness were distinctly enhanced, which could be ascribed to large specific area of nHAp and the corresponding stress transfer.

  3. To favor survival under food shortage, the brain disables costly memory.

    Science.gov (United States)

    Plaçais, Pierre-Yves; Preat, Thomas

    2013-01-25

    The brain regulates energy homeostasis in the organism. Under resource shortage, the brain takes priority over peripheral organs for energy supply. But can the brain also down-regulate its own consumption to favor survival? We show that the brain of Drosophila specifically disables the costly formation of aversive long-term memory (LTM) upon starvation, a physiological state required for appetitive LTM formation. At the neural circuit level, the slow oscillations normally triggered in two pairs of dopaminergic neurons to enable aversive LTM formation were abolished in starved flies. Transient artificial activation of these neurons during training restored LTM formation in starved flies but at the price of a reduced survival. LTM formation is thus subject to adaptive plasticity that helps survival under food shortage.

  4. Favorable associations with alcohol and impaired self-regulation: A behavioral economic analysis.

    Science.gov (United States)

    Luehring-Jones, Peter; Dennis-Tiwary, Tracy A; Murphy, James G; Dennhardt, Ashley; Lindgren, Kristen P; Yarmush, Devorah E; Erblich, Joel

    2016-06-01

    Recent research has demonstrated that both poor self-regulation and favorable implicit associations toward alcohol can play important roles in predicting drinking. Less well studied, however, is how the interplay between implicit associations and self-regulation may impact decisions about alcohol consumption. Behavioral economics is one important tool that may provide insight into the cognitive processes that impact demand for alcohol and drinking decisions. Healthy young adult participants completed an Implicit Association Task (IAT) that measured the strength of associations between approach/avoid attributes and target alcohol/neutral images. Impaired self-regulation was assessed by a classic delay discounting task. Participants also completed an Alcohol Purchase Task (APT), which yields multiple behavioral economic indices, chief among which are intensity (the number of drinks a participant would consume if the drinks were free) and elasticity (the degree to which an increased per-drink price impacts the number of drinks consumed in a hypothetical drinking situation). Finally, participants completed a timeline follow-back assessment of past-90-day drinking. Findings indicated that implicit approach associations toward alcohol predicted increased demand for alcohol on the APT. Although delay discounting did not have a direct effect on demand for alcohol, there was a significant interaction between IAT and delay discounting, such that higher implicit alcohol approach associations predicted particularly high demand for alcohol among participants with poorer self-regulation. APT and IAT, in turn, predicted self-reported drinking behavior. These results suggest that favorable attitudes toward alcohol, together with poor self-regulation, can significantly impact drinking decisions in healthy young adults. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  5. Protein phosphatase methylesterase-1 (PME-1) expression predicts a favorable clinical outcome in colorectal cancer.

    Science.gov (United States)

    Kaur, Amanpreet; Elzagheid, Adam; Birkman, Eva-Maria; Avoranta, Tuulia; Kytölä, Ville; Korkeila, Eija; Syrjänen, Kari; Westermarck, Jukka; Sundström, Jari

    2015-12-01

    Colorectal cancer (CRC) accounts for high mortality. So far, there is lack of markers capable of predicting which patients are at risk of aggressive course of the disease. Protein phosphatase-2A (PP2A) inhibitor proteins have recently gained interest as markers of more aggressive disease in certain cancers. Here, we report the role of PP2A inhibitor PME-1 in CRC. PME-1 expression was assessed from a rectal cancer patient cohort by immunohistochemistry, and correlations were performed for various clinicopathological variables and patient survival. Rectal cancer patients with higher cytoplasmic PME-1 protein expression (above median) had less recurrences (P = 0.003, n = 195) and better disease-free survival (DFS) than the patients with low cytoplasmic PME-1 protein expression (below median). Analysis of PPME-1 mRNA expression from TCGA dataset of colon and rectal adenocarcinoma (COADREAD) patient cohort confirmed high PPME1 expression as an independent protective factor predicting favorable overall survival (OS) (P = 0.005, n = 396) compared to patients with low PPME1 expression. CRC cell lines were used to study the effect of PME-1 knockdown by siRNA on cell survival. Contrary to other cancer types, PME-1 inhibition in CRC cell lines did not reduce the viability of cells or the expression of active phosphorylated AKT and ERK proteins. In conclusion, PME-1 expression predicts for a favorable outcome of CRC patients. The unexpected role of PME-1 in CRC in contrast with the oncogenic role of PP2A inhibitor proteins in other malignancies warrants further studies of cancer-specific function for each of these proteins. © 2015 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

  6. Endoscopic Mucosal Healing Predicts Favorable Clinical Outcomes in Inflammatory Bowel Disease: A Meta-analysis.

    Science.gov (United States)

    Reinink, Andrew R; Lee, Terrence C; Higgins, Peter D R

    2016-08-01

    Mucosal healing (MH) in inflammatory bowel disease has been associated with improved long-term clinical outcomes. Uncertainty remains as to the magnitude of this effect and to how this association changes with time and degree of healing. PubMed, EMBASE, and Web of Science searches identified 1570 citations. Screening of abstracts identified 155 articles for full-text review, of which 19 met inclusion criteria. For 3 outcomes of interest (surgeries, hospitalizations, remission), weighted random-effects meta-analysis was performed. In pooled analysis, MH predicted fewer major abdominal surgeries (relative risk [RR], 0.34; 95% confidence interval [CI], 0.26-0.46), increased remission (RR, 1.84; 95% CI, 1.43-2.36), and fewer hospitalizations (RR, 0.58; 95% CI, 0.42-0.78). Complete MH and partial MH both showed significantly higher rates of favorable outcomes. Separate analyses for Crohn's disease and ulcerative colitis showed identical patterns for surgeries and remission. When subjects with no healing were excluded, and complete versus partial healing was compared, rates of surgery were not significantly different (RR, 0.82; 95% CI, 0.46-1.44). However, complete healing was superior in predicting corticosteroid-free remission (RR, 1.71; 95% CI, 1.24-2.34). Meta-regression found that the predictive power of this complete versus partial healing distinction was strongly associated with the duration of follow-up after endoscopy. MH is a strong predictor of fewer surgeries, long-term clinical remission, and fewer hospitalizations. Complete healing is not significantly more favorable than partial healing for predicting surgeries or hospitalizations, but it did predict higher rates of clinical remission. This benefit of complete MH over partial healing increases with follow-up time.

  7. Association and Validation of Yield-Favored Alleles in Chinese Cultivars of Common Wheat (Triticumaestivum L..

    Directory of Open Access Journals (Sweden)

    Jie Guo

    Full Text Available Common wheat is one of the most important crops in China, which is the largest producer in the world. A set of 230 cultivars was used to identify yield-related loci by association mapping. This set was tested for seven yield-related traits, viz. plant height (PH, spike length (SL, spikelet number per spike (SNPS, kernel number per spike (KNPS, thousand-kernel weight (TKW, kernel weight per spike (KWPS, and sterile spikelet number (SSN per plant in four environments. A total of 106 simple sequence repeat (SSR markers distributed on all 21 chromosomes were used to screen the set. Twenty-one and 19 of them were associated with KNPS and TKW, respectively. Association mapping detected 73 significant associations across 50 SSRs, and the phenotypic variation explained (R2 by the associations ranged from 1.54 to 23.93%. The associated loci were distributed on all chromosomes except 4A, 7A, and 7D. Significant and potentially new alleles were present on 8 chromosomes, namely 1A, 1D, 2A, 2D, 3D, 4B, 5B, and 6B. Further analysis showed that genetic effects of associated loci were greatly influenced by association panels, and the R2 of crucial loci were lower in modern cultivars than in the mini core collection, probably caused by strong selection in wheat breeding. In order to confirm the results of association analysis, yield-related favorable alleles Xgwm135-1A138, Xgwm337-1D186, Xgwm102-2D144, and Xgwm132-6B128 were evaluated in a double haploid (DH population derived from Hanxuan10 xLumai14.These favorable alleles that were validated in various populations might be valuable in breeding for high-yield.

  8. Operational amplifiers

    CERN Document Server

    Dostal, Jiri

    1993-01-01

    This book provides the reader with the practical knowledge necessary to select and use operational amplifier devices. It presents an extensive treatment of applications and a practically oriented, unified theory of operational circuits.Provides the reader with practical knowledge necessary to select and use operational amplifier devices. Presents an extensive treatment of applications and a practically oriented, unified theory of operational circuits

  9. Spatial Operations

    Directory of Open Access Journals (Sweden)

    Anda VELICANU

    2010-09-01

    Full Text Available This paper contains a brief description of the most important operations that can be performed on spatial data such as spatial queries, create, update, insert, delete operations, conversions, operations on the map or analysis on grid cells. Each operation has a graphical example and some of them have code examples in Oracle and PostgreSQL.

  10. Driver and dispatcher perceptions of AATA's Advanced Operating System

    Science.gov (United States)

    1999-01-01

    This report details results of focus groups and written surveys conducted with AATA motor coach operators. The drivers' early verdict on AOS is favorable overall; limitations in : communication are generally unwelcome, but other services such as auto...

  11. Favorable Street Canyon Aspect Ratios for Pollutant Removal- a Large-Eddy Simulation Approach

    Science.gov (United States)

    Chung, T. N.; Liu, C.

    2010-12-01

    Given the limited land resource, urbanization is one of the solutions to the current rapid economic development and population growth. Narrow streets flanked by high-rise buildings, also known as street canyons, are commonly found in metropolises nowadays. In recent years, this issue has been aroused the public awareness that the air pollutants from domestic sources and vehicular emissions are unable to be removed but trapped inside the street canopy level threatening human health and our living environment. A thorough understanding of the pollutant removal mechanism is the key step to rectify the current poor urban air quality. This study is therefore conceived to examine how the pollutant removal is related to the street width and building height. Large-eddy simulation (LES) with the one-equation subgrid-scale (SGS) turbulence model is employed to investigate the characteristic ventilation and pollutant transport in idealized two-dimensional (2D) street canyons of different building-height-to-street-width (aspect) ratios (ARs) h/b. Model validation is performed by comparing the LES results with those of k-ɛ turbulence model and laboratory experiments. A consistent trend of the pollutant exchange rate (PCH) among the LES, k-ɛ turbulence model, and experimental results is obtained. While its drag is largest, the street canyon of AR = 0.5 is found to be most favorable in the pollutant removal perspective. This finding seems contradict with the presumption that the smaller the AR (wider the street), the more efficient the pollutants removal. In the isolated roughness regime the flows in (wider) street canyons, the entrainment from the prevailing flow aloft down into the ground level purging pollutant away. On the contrary in the skimming flow regime, in (narrower) street canyons, the recirculating flows inside the street canyon are isolated from the prevailing flow in which the (vertical) pollutant removal is governed by roof-level intermittency. Unexpectedly, in

  12. Designation of less favorable areas by the regionalization of soil degradation on various spatial scales

    Science.gov (United States)

    Pásztor, L.; Szabó, J.; Bakacsi, Zs.; Laborczi, A.

    2009-04-01

    One of the main objectives of the EU's Common Agricultural Policy is to encourage maintaining agricultural production in less favorable areas (LFA) in order (among others) to sustain agricultural production and use natural resources, in such a way to secure both stable production and income to farmers and to protect the environment. LFA assignment has both ecological and severe economical aspects. Delimitation of LFAs can be carried out by using biophysical diagnostic criteria on low soil productivity and poor climate conditions. Identification of low-productivity areas requires regionalization of soil functions related to food and other biomass production. This process can be carried out in different scales from national to local level, but always requires map-based pedological and further environmental information with appropriate spatial resolution. For the regionalization of less productive areas in national scale a functional approach was used which integrates the knowledge on soil degradation processes in nationwide level. Specific soil threats were classified into ranked categories. Supposing (quasi)uniform distribution of vulnerability measure along these classes, we introduced a "standardized" value as a ratio of the class order to the maximum class order expressed in percentage. For the overall spatial characterization of degradation status, spatial information was integrated in a result map by summarizing the degradation specific "standardized" cell values. This map in one hand has been used for the delineation of soil degradation regions. On the other hand appropriate spatial aggregation of index values on geographical and administrative regions is suitable for their quantitative comparison thus they can be ranked and this feature can be used for the identification of less favorable areas. At the more detailed, county level the Digital Kreybig Soil Information System was used as a tool of the regionalization of soil functions related to soil

  13. Favorable prognostic value of SOCS2 and IGF-I in breast cancer

    Directory of Open Access Journals (Sweden)

    Daxenbichler Günter

    2007-07-01

    Full Text Available Abstract Background Suppressor of cytokine signaling (SOCS proteins comprise a protein family, which has initially been described as STAT induced inhibitors of the Jak/Stat pathway. Recent in vivo and in vitro studies suggest that SOCS proteins are also implicated in cancer. The STAT5 induced IGF-I acts as an endocrine and para/autocrine growth and differentiation factor in mammary gland development. Whereas high levels of circulating IGF-I have been associated with increased cancer risk, the role of autocrine acting IGF-I is less clear. The present study is aimed to elucidate the clinicopathological features associated with SOCS1, SOCS2, SOCS3, CIS and IGF-I expression in breast cancer. Methods We determined the mRNA expression levels of SOCS1, SOCS2, SOCS3, CIS and IGF-I in 89 primary breast cancers by reverse transcriptase PCR. SOCS2 protein expression was further evaluated by immuno-blot and immunohistochemistry. Results SOCS2 expression inversely correlated with histopathological grade and ER positive tumors exhibited higher SOCS2 levels. Patients with high SOCS2 expression lived significantly longer (108.7 vs. 77.7 months; P = 0.015 and high SOCS2 expression proved to be an independent predictor for good prognosis (HR = 0.45, 95% CI 0.23 – 0.91, P = 0.026. In analogy to SOCS2, high IGF-I expression was an independent predictor for good prognosis in the entire patient cohort. In the subgroup of patients with lymph-node negative disease, high IGF-I was a strong predictor for favorable outcome in terms of overall survival and relapse free survival (HR = 0.075, 95% CI 0.014 – 0.388, P = 0.002. Conclusion This is the first report on the favorable prognostic value of high SOCS2 expression in primary mammary carcinomas. Furthermore a strong association of high IGF-I expression levels with good prognosis was observed especially in lymph-node negative patients. Our results suggest that high expression of the STAT5 target genes SOCS2 and IGF

  14. Complex Interactions: Why President Clinton De-Linked Human Rights Conditions from the Criteria for China's Most Favored Nation Status

    National Research Council Canada - National Science Library

    Bolton, Edward L

    2000-01-01

    ... China's Most Favored Nation (MFN) status to its human rights record. In 1994, despite its poor progress in human rights issues, President Clinton announced his intention to support continuation of China's MFN status...

  15. Subsurface stratigraphy and uranium--vanadium favorability of the Morrison Formation, Sage Plain Area, southeastern Utah and southwestern Colorado

    International Nuclear Information System (INIS)

    Girdley, W.A.; Flook, J.E.; Harris, R.E.

    1975-08-01

    The four members of the Morrison Formation that are recognizable in the area studied are, in ascending order, the Salt Wash, Recapture, Westwater Canyon, and Brushy Basin. The Salt Wash member has the highest uranium favorability of all the Morrison strata in the area studied. An especially favorable area, in which the Salt Wash interval is thick and contains several thick sandstones, is situated on either side of the Utah-Colorado state line between Monticello, Utah, and Dove Creek, Colorado. The upper Morrison strata (Westwater Canyon and Brushy Basin members) have low uranium favorability. The Westwater Canyon member contains adequate sandstones but lacks known uranium deposits in the project area. The Brushy Basin member, although rated as having low potential, nevertheless does possess some attributes that make it worthy of further attention. The Recapture member does not contain sufficient well-developed sandstones or uranium deposits to merit its being classed as favorable for potential uranium-vanadium resources. (LK)

  16. pseudomonotone operators

    Directory of Open Access Journals (Sweden)

    Ram U. Verma

    2000-01-01

    Full Text Available We present the solvability of a class of nonlinear variational inequalities involving pseudomonotone operators in a locally convex Hausdorff topological vector spaces setting. The obtained result generalizes similar variational inequality problems on monotone operators.

  17. Anthropogenic N Deposition Slows Decay by Favoring Bacterial Metabolism: Insights from Metagenomic Analyses

    Science.gov (United States)

    Freedman, Zachary B.; Upchurch, Rima A.; Zak, Donald R.; Cline, Lauren C.

    2016-01-01

    Litter decomposition is an enzymatically-complex process that is mediated by a diverse assemblage of saprophytic microorganisms. It is a globally important biogeochemical process that can be suppressed by anthropogenic N deposition. In a northern hardwood forest ecosystem located in Michigan, USA, 20 years of experimentally increased atmospheric N deposition has reduced forest floor decay and increased soil C storage. Here, we paired extracellular enzyme assays with shotgun metagenomics to assess if anthropogenic N deposition has altered the functional potential of microbial communities inhabiting decaying forest floor. Experimental N deposition significantly reduced the activity of extracellular enzymes mediating plant cell wall decay, which occurred concurrently with changes in the relative abundance of metagenomic functional gene pathways mediating the metabolism of carbohydrates, aromatic compounds, as well as microbial respiration. Moreover, experimental N deposition increased the relative abundance of 50 of the 60 gene pathways, the majority of which were associated with saprotrophic bacteria. Conversely, the relative abundance and composition of fungal genes mediating the metabolism of plant litter was not affected by experimental N deposition. Future rates of atmospheric N deposition have favored saprotrophic soil bacteria, whereas the metabolic potential of saprotrophic fungi appears resilient to this agent of environmental change. Results presented here provide evidence that changes in the functional capacity of saprotrophic soil microorganisms mediate how anthropogenic N deposition increases C storage in soil. PMID:26973633

  18. A new algorithm for determining collimator angles that favor efficiency in MLC based IMRT delivery

    International Nuclear Information System (INIS)

    Wang, David; Hill, R.W.; Lam, S.

    2004-01-01

    A new algorithm to determine collimator angles that favor delivery efficiency of intensity modulated radiotherapy plans was developed. It was found that the number of segments and monitor units (MUs) were largely reduced with the set of collimator angles determined with the new algorithm without compromising plan quality. The improvement of delivery efficiency using the new algorithm depends on the size and shape of the target(s), the number of modulation levels, and the type of leaf-sequencing algorithm. In a typical prostate case, when a sweeping leaf-sequencer is used for Varian 120 leaf (0.5x0.5 cm2 beamlet), 80 leaf (1x1 cm2 beamlet) and Elekta 40 leaf (1x1 cm2 beamlet), the number of segments was reduced by 42%, 29%, and 5%, respectively. The number of MUs was reduced by 41%, 35%, and 10%. For the Siemens MLC (IMFAST TM leaf sequencer, 1x1 cm2 beamlet) the segment reduction was 32% and the MU reduction was 14%. Comparison of the plans using the new and Brahme algorithms, in terms of target conformity index and dose volume histogram of the organs at risk, showed that the quality of the plans using the new algorithm was uncompromised. Similar results were obtained for a set of head and neck treatment plans

  19. Social heuristics and social roles: Intuition favors altruism for women but not for men.

    Science.gov (United States)

    Rand, David G; Brescoll, Victoria L; Everett, Jim A C; Capraro, Valerio; Barcelo, Hélène

    2016-04-01

    Are humans intuitively altruistic, or does altruism require self-control? A theory of social heuristics, whereby intuitive responses favor typically successful behaviors, suggests that the answer may depend on who you are. In particular, evidence suggests that women are expected to behave altruistically, and are punished for failing to be altruistic, to a much greater extent than men. Thus, women (but not men) may internalize altruism as their intuitive response. Indeed, a meta-analysis of 13 new experiments and 9 experiments from other groups found that promoting intuition relative to deliberation increased giving in a Dictator Game among women, but not among men (Study 1, N = 4,366). Furthermore, this effect was shown to be moderated by explicit sex role identification (Study 2, N = 1,831): the more women described themselves using traditionally masculine attributes (e.g., dominance, independence) relative to traditionally feminine attributes (e.g., warmth, tenderness), the more deliberation reduced their altruism. Our findings shed light on the connection between gender and altruism, and highlight the importance of social heuristics in human prosociality. (c) 2016 APA, all rights reserved).

  20. Disruption of NSD1 in head and neck cancer promotes favorable chemotherapeutic responses linked to hypomethylation.

    Science.gov (United States)

    Bui, Nam; Huang, Justin K; Bojorquez-Gomez, Ana; Licon, Katherine; Sanchez, Kyle S; Tang, Sean N; Beckett, Alex N; Wang, Tina; Zhang, Wei; Shen, John Paul; Kreisberg, Jason F; Ideker, Trey

    2018-04-10

    Human papillomavirus (HPV) negative head and neck squamous cell carcinoma (HNSCC) represents a distinct classification of cancer with poor expected outcomes. Of the 11 genes recurrently mutated in HNSCC, we identify a singular and substantial survival advantage for mutations in the gene encoding Nuclear Set Domain Containing Protein 1 (NSD1), a histone methyltransferase altered in approximately 10% of patients. This effect, a 55% decrease in risk of death in NSD1-mutated versus non-mutated patients, can be validated in an independent cohort. NSD1 alterations are strongly associated with widespread genome hypomethylation in the same tumors, to a degree not observed for any other mutated gene. To address whether NSD1 plays a causal role in these associations, we use CRISPR-Cas9 to disrupt NSD1 in HNSCC cell lines and find that this leads to substantial CpG hypomethylation and sensitivity to cisplatin, a standard chemotherapy in head and neck cancer, with a 40 - 50% decrease in IC50. Such results are reinforced by a survey of 1,001 cancer cell lines, in which loss-of-function NSD1 mutations have an average 23% decrease in cisplatin IC50 compared to cell lines with wild type NSD1. This study identifies a favorable subtype of head and neck cancer linked to NSD1 mutation, hypomethylation and cisplatin sensitivity. Copyright ©2018, American Association for Cancer Research.

  1. Genotypic diversity effects on the performance of Taraxacum officinale populations increase with time and environmental favorability.

    Directory of Open Access Journals (Sweden)

    Emily B M Drummond

    Full Text Available Within-population genetic diversity influences many ecological processes, but few studies have examined how environmental conditions may impact these short-term diversity effects. Over four growing seasons, we followed experimental populations of a clonal, ubiquitous weed, Taraxacum officinale, with different numbers of genotypes in relatively favorable fallow field and unfavorable mowed lawn environmental treatments. Population performance (measured as total leaf area, seed production or biomass clearly and consistently increased with diversity, and this effect became stronger over the course of the experiment. Diversity effects were stronger, and with different underlying mechanisms, in the fallow field versus the mowed lawn. Large genotypes dominated in the fallow field driving overyielding (via positive selection effects, whereas in the mowed lawn, where performance was limited by regular disturbance, there was evidence for complementarity among genotypes (with one compact genotype in particular performing better in mixture than monoculture. Hence, we predict stronger genotypic diversity effects in environments where intense intraspecific competition enhances genotypic differences. Our four-year field experiment plus seedling establishment trials indicate that genotypic diversity effects have far-reaching and context-dependent consequences across generations.

  2. Genotypic diversity effects on the performance of Taraxacum officinale populations increase with time and environmental favorability.

    Science.gov (United States)

    Drummond, Emily B M; Vellend, Mark

    2012-01-01

    Within-population genetic diversity influences many ecological processes, but few studies have examined how environmental conditions may impact these short-term diversity effects. Over four growing seasons, we followed experimental populations of a clonal, ubiquitous weed, Taraxacum officinale, with different numbers of genotypes in relatively favorable fallow field and unfavorable mowed lawn environmental treatments. Population performance (measured as total leaf area, seed production or biomass) clearly and consistently increased with diversity, and this effect became stronger over the course of the experiment. Diversity effects were stronger, and with different underlying mechanisms, in the fallow field versus the mowed lawn. Large genotypes dominated in the fallow field driving overyielding (via positive selection effects), whereas in the mowed lawn, where performance was limited by regular disturbance, there was evidence for complementarity among genotypes (with one compact genotype in particular performing better in mixture than monoculture). Hence, we predict stronger genotypic diversity effects in environments where intense intraspecific competition enhances genotypic differences. Our four-year field experiment plus seedling establishment trials indicate that genotypic diversity effects have far-reaching and context-dependent consequences across generations.

  3. Factors for Predicting Favorable Outcome of Percutaneous Epidural Adhesiolysis for Lumbar Disc Herniation

    Directory of Open Access Journals (Sweden)

    Sang Ho Moon

    2017-01-01

    Full Text Available Background. Lower back pain is a common reason for disability and the most common cause is lumbar disc herniation. Percutaneous epidural adhesiolysis has been applied to relieve pain and increase the functional capacity of patients who present this condition. Objectives. In this study, we retrospectively evaluated the factors which predict the outcome of percutaneous epidural adhesiolysis in patients who were diagnosed with lumbar disc herniation. Methods. Electronic medical records of patients diagnosed with lumbar disc herniation who have received percutaneous epidural adhesiolysis treatment were reviewed. The primary outcome was the factors that were associated with substantial response of ≥4 points or ≥50% of pain relief in the numerical rating scale pain score 12 months after the treatment. Results. Multivariate logistic regression analysis demonstrated that the presence of high-intensity zone (HIZ at magnetic resonance imaging was a predictor of substantial response to percutaneous epidural adhesiolysis for 12 months (P=0.007. The presence of a condition involving the vertebral foramen was a predictor for unsuccessful response after 12 months (P=0.02. Discussion and Conclusion. The presence of HIZ was a predictor of favorable long-term outcome after percutaneous epidural adhesiolysis for the treatment of lower back pain with radicular pain caused by lumbar disc herniation.

  4. Balanced bilinguals favor lexical processing in their opaque language and conversion system in their shallow language.

    Science.gov (United States)

    Buetler, Karin A; de León Rodríguez, Diego; Laganaro, Marina; Müri, René; Nyffeler, Thomas; Spierer, Lucas; Annoni, Jean-Marie

    2015-11-01

    Referred to as orthographic depth, the degree of consistency of grapheme/phoneme correspondences varies across languages from high in shallow orthographies to low in deep orthographies. The present study investigates the impact of orthographic depth on reading route by analyzing evoked potentials to words in a deep (French) and shallow (German) language presented to highly proficient bilinguals. ERP analyses to German and French words revealed significant topographic modulations 240-280 ms post-stimulus onset, indicative of distinct brain networks engaged in reading over this time window. Source estimations revealed that these effects stemmed from modulations of left insular, inferior frontal and dorsolateral regions (German>French) previously associated to phonological processing. Our results show that reading in a shallow language was associated to a stronger engagement of phonological pathways than reading in a deep language. Thus, the lexical pathways favored in word reading are reinforced by phonological networks more strongly in the shallow than deep orthography. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Heightened exposure to parasites favors the evolution of immunity in brood parasitic cowbirds

    Science.gov (United States)

    Hahn, Caldwell; Reisen, William K.

    2011-01-01

    Immunologists and evolutionary biologists are interested in how the immune system evolves to fit an ecological niche. We studied the relationship between exposure to parasites and strength of immunity by investigating the response of two species of New World cowbirds (genus Molothrus, Icteridae), obligate brood parasites with contrasting life history strategies, to experimental arboviral infection. The South American shiny cowbird (M. bonariensis) is an extreme host-generalist that lays its eggs in the nests of >225 different avian species. The Central American bronzed cowbird (M. aeneus) is a relative host-specialist that lays its eggs preferentially in the nests of approximately 12 orioles in a single sister genus. West Nile virus provided a strong challenge and delineated immune differences between these species. The extreme host-generalist shiny cowbird, like the North American host-generalist, the brown-headed cowbird, showed significantly lower viremia to three arboviruses than related icterid species that were not brood parasites. The bronzed cowbird showed intermediate viremia. These findings support the interpretation that repeated exposure to a high diversity of parasites favors the evolution of enhanced immunity in brood parasitic cowbirds and makes them useful models for future studies of innate immunity.

  6. Potential climate change favored expansion of a range limited species, Haematostaphis barteri Hook f.

    Directory of Open Access Journals (Sweden)

    Jacob Koundouonon Moutouama

    2016-12-01

    Full Text Available Understanding impact of climate change on range breadth of rare species can improve the ability to anticipate their decline or expension and take appropriate conservation measures. Haematatostaphis barteri is an agroforestry species of the Sudanian centre of endemism in Africa. We investigeted impact of climate change on range of suitable habitats for this species in Benin,using the Maximum Entropy algorithm under R software. Five environmental variables were used with the regional climate model under the new Representation Concentration Pathways (RCP. Moisture Index of the Moist Quarter and Slope variability had the greatest predictive importance for the range of suitable habitats for H. barteri. Its Potential breadth was found to be currently limited to the Atacora Mountain Chain (AMC and covers 0.51% of national territory. Climate change was projected to favor expansion of suitable habitats for H. barteri by 0.12% and 0.05%, respectively for the RCP4.5 and RCP8.5. These habitats were however mostly out of the local protected areas network. Climate change would extend range of habitats for H. barteri. Observed protection gaps suggest need for integrating this species into formal in situ, on-farm or ex situ conservation schemes.

  7. Arguments in Favor of Moving to a Sustainable Business Model in the Apiary Industry

    Directory of Open Access Journals (Sweden)

    Panța Nancy Diana

    2017-12-01

    Full Text Available Today’s society faces major challenges in meeting future global food demands and solving biodiversity loss, and it quickly needs to find ways in addressing these issues. The places to look for solutions come from the economic sectors that employ the most powerful pressure on these issues such as agriculture. Apiculture, as a branch of agriculture is being more and more recognized as sustaining human life and contributing to sustainability. However, the sector records a progressive decline of honey bees. Therefore, a rapid restructuring needs to take place in agricultural markets, in general, as well as in apiary agribusinesses. Although important, technological progress is insufficient in providing the necessary changes to achieve long-term economic, social and environmental sustainability, which should be considered both within and between generations. Consequently, sustainable business models encourage sustainable development through a triple bottom line approach and provide an analytical tool for firms into assessing the different aspects that are combined in order to create value. Since literature has paid little attention to the sustainable development in the apiary agribusiness, the present paper aims to link the two using a business model perspective and bring arguments in favor of moving to a sustainable business model.

  8. The Norwood procedure: in favor of the RV-PA conduit.

    Science.gov (United States)

    Barron, David J

    2013-01-01

    Evolution of the Norwood procedure has culminated in there currently being three treatment strategies available for initial management: the 'classical' Norwood (utilizing a Blalock-Taussig shunt), the Norwood with right-ventricle to pulmonary artery (RV-PA) conduit, and the 'hybrid' Norwood procedure utilizing bilateral pulmonary artery banding and ductal stenting. Each variant has its potential advantages and disadvantages, and this paper looks to examine the evidence in favor of each strategy, with emphasis on the supportive data for the RV-PA conduit. The 'classical' procedure has the benefit of the greatest accumulated surgical experience and avoids any incision into the ventricle. However, the diastolic run-off of the Blalock-Taussig shunt can cause hemodynamic instability and unpredictable coronary steal phenomenon. The RV-PA conduit has the advantage of maintaining diastolic pressure with a more stable postoperative course, but at the cost of a ventriculotomy that may have detrimental long-term sequelae. The 'hybrid' procedure has the advantage of avoiding cardiopulmonary bypass, but does not always secure coronary blood flow and has a high inter-stage morbidity and reintervention rate. The evidence shows that each technique may have its place in future management, and that treatment algorithms could emerge that direct the choice of procedure for specific patient groups. Copyright © 2013 Elsevier Inc. All rights reserved.

  9. Does night work favor sleep-related accidents in police officers?

    Science.gov (United States)

    Tafil-Klawe, M; Laudencka, A; Klawe, J J; Miśkowiec, I

    2005-09-01

    Several studies of sleep-breathing physiology have suggested that sleep deprivation may worsen obstructive sleep apnea. The aim of the study was to determine the direct effect of night work on breathing variables during sleep in fast-rotating shift workers. Twenty one men - police officers, fast-rotating shift workers, underwent polysomnography on 2 occasions: under a normal sleeping condition after day work and after sleep deprivations after night work. Both sleep studies were conducted within 2 to 3 weeks of each other. Approximately half of the group was tested under control conditions (day work) first, with the remaining subjects tested under sleep deprivation conditions (night work) first. After a night shift the subjects did not show a significantly different apnea-hypopnea-index (AHI). However, night work significantly increased several breathing variables recorded during sleep after it: total duration of obstructive apneas (OA) during REM sleep, mean duration of OA during arousal, total duration of OA during NREM sleep, apnea index during arousal, mean length of OA during sleep period time, total duration of OA during sleep period time, mean length of OA during total sleep time, mean length of hypopnea during REM sleep, total duration of hypopnea during sleep period time and during total sleep time, maximal length of central apnea and OA, and total sleep time. Night work does not favor obstructive sleep apnea episodes during sleep, but worsens many an obstructive sleep apnea variable, as measured by polysomnography.

  10. Blood group antigen A type 3 expression is a favorable prognostic factor in advanced NSCLC.

    Science.gov (United States)

    Schmidt, L H; Kuemmel, A; Schliemann, C; Schulze, A; Humberg, J; Mohr, M; Görlich, D; Hartmann, W; Bröckling, S; Marra, A; Hillejan, L; Goletz, S; Karsten, U; Berdel, W E; Spieker, T; Wiewrodt, R

    2016-02-01

    Several blood group-related carbohydrate antigens are prognosis-relevant markers of tumor tissues. A type 3 (repetitive A) is a blood group antigen specific for A1 erythrocytes. Its potential expression in tumor tissues has so far not been examined. We have evaluated its expression in normal lung and in lung cancer using a novel antibody (A69-A/E8). For comparison an anti-A antibody specific to A types 1 and 2 was used, because its expression on lung cancer tissue has been previously reported to be of prognostic relevance. Resected tissue samples of 398 NSCLC patients were analyzed in immunohistochemistry using tissue microarrays. Expression of A type 3 was not observed in non-malignant lung tissues. A type 3 was expressed on tumor cells of around half of NSCLC patients of blood group A1 (ptype 1/2 antigen was observed (p=0.562), the expression of A type 3 by tumor cells indicated a highly significant favorable prognosis among advanced NSCLC patients (p=0.011) and in NSCLC patients with lymphatic spread (p=0.014). Univariate prognostic results were confirmed in a Cox proportional hazards model. In this study we present for the first time prognostic data for A type 3 antigen expression in lung cancer patients. Prospective studies should be performed to confirm the prognostic value of A type 3 expression for an improved risk stratification in NSCLC patients. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  11. FLARE STARS—A FAVORABLE OBJECT FOR STUDYING MECHANISMS OF NONTHERMAL ASTROPHYSICAL PHENOMENA

    Energy Technology Data Exchange (ETDEWEB)

    Oks, E. [Physics Department, 206 Allison Lab., Auburn University, Auburn, AL 36849 (United States); Gershberg, R. E. [Crimean Astrophysical Observatory, Nauchny, Bakhchisaray region, Crimea, 298409 (Russian Federation)

    2016-03-01

    We present a spectroscopic method for diagnosing a low-frequency electrostatic plasma turbulence (LEPT) in plasmas of flare stars. This method had been previously developed by one of us and successfully applied to diagnosing the LEPT in solar flares. In distinction to our previous applications of the method, here we use the latest advances in the theory of the Stark broadening of hydrogen spectral lines. By analyzing observed emission Balmer lines, we show that it is very likely that the LEPT was developed in several flares of AD Leo, as well as in one flare of EV Lac. We found the LEPT (though of different field strengths) both in the explosive/impulsive phase and at the phase of the maximum, as well as at the gradual phase of the stellar flares. While for solar flares our method allows diagnosing the LEPT only in the most powerful flares, for the flare stars it seems that the method allows revealing the LEPT practically in every flare. It should be important to obtain new and better spectrograms of stellar flares, allowing their analysis by the method outlined in the present paper. This can be the most favorable way to the detailed understanding of the nature of nonthermal astrophysical phenomena.

  12. Music, clicks, and their imaginations favor differently the event-based timing component for rhythmic movements.

    Science.gov (United States)

    Bravi, Riccardo; Quarta, Eros; Del Tongo, Claudia; Carbonaro, Nicola; Tognetti, Alessandro; Minciacchi, Diego

    2015-06-01

    The involvement or noninvolvement of a clock-like neural process, an effector-independent representation of the time intervals to produce, is described as the essential difference between event-based and emergent timing. In a previous work (Bravi et al. in Exp Brain Res 232:1663-1675, 2014a. doi: 10.1007/s00221-014-3845-9 ), we studied repetitive isochronous wrist's flexion-extensions (IWFEs), performed while minimizing visual and tactile information, to clarify whether non-temporal and temporal characteristics of paced auditory stimuli affect the precision and accuracy of the rhythmic motor performance. Here, with the inclusion of new recordings, we expand the examination of the dataset described in our previous study to investigate whether simple and complex paced auditory stimuli (clicks and music) and their imaginations influence in a different way the timing mechanisms for repetitive IWFEs. Sets of IWFEs were analyzed by the windowed (lag one) autocorrelation-wγ(1), a statistical method recently introduced for the distinction between event-based and emergent timing. Our findings provide evidence that paced auditory information and its imagination favor the engagement of a clock-like neural process, and specifically that music, unlike clicks, lacks the power to elicit event-based timing, not counteracting the natural shift of wγ(1) toward positive values as frequency of movements increase.

  13. Preliminary study of favorability for uranium resources in Juab County, Utah

    International Nuclear Information System (INIS)

    Leedom, S.H.; Mitchell, T.P.

    1978-02-01

    The best potential for large, low-grade uranium deposits in Juab County is in the hydrothermally altered vitric tuffs of Pliocene age. The lateral extent of the altered tuffs may be determined by subsurface studies around the perimeter of the volcanic centers in the Thomas Range and the Honeycomb Hills. Because the ring-fracture zone associated with collapse of the Thomas caldera was a major control for hydrothermal uranium deposits, delineation of the northern and eastern positions of the ring-fracture zone is critical in defining favorable areas for uranium deposits. A small, medium-grade ore deposit in tuffaceous sand of Pliocene age at the Yellow Chief mine in Dugway Dell is unique in origin, and the probability of discovering another deposit of this type is low. A deposit of this type may be present under alluvial cover in the northwestern Drum Mountains along the southern extension of the ring-fracture zone of the Thomas caldera. Festoonlike iron oxide structures and uranium deposition within permeable sandstone horizons indicate that the Yellow Chief deposit was formed by recent ground-water circulation. Granitic intrusive rocks in the Deep Creek Range and in Desert Mountain contain isolated epigenetic vein-type deposits. These rocks could be a source of arkosic sediments buried in adjacent valleys. The Pleistocene lacustrine sediments and playa lake brines may contain concentrations of uranium leached from uranium-rich rocks

  14. Organic nitrates favor regression of left ventricular hypertrophy in hypertensive patients on chronic peritoneal dialysis.

    Science.gov (United States)

    Li, Han; Wang, Shixiang

    2013-01-07

    The aim of the study was to evaluate the effect of nitrates on left ventricular hypertrophy (LVH) in hypertensive patients on chronic peritoneal dialysis (PD). Sixty-four PD patients with hypertension were enrolled in this study. All patients accepted antihypertensive drugs at baseline. Thirty-two patients (nitrate group) took isosorbide mononitrate for 24 weeks. The remaining 32 patients (non-nitrate group) took other antihypertensive drugs. Blood pressure (BP), left ventricular mass index (LVMI) and plasma asymmetric dimethylarginine (ADMA) were monitored. Subjects with normal renal function were included as the control group (n = 30). At baseline, plasma ADMA levels in PD patients were significantly higher than the control group, but there was no significant difference in plasma ADMA levels between the two groups. At the end of the 24-week period, BP, LVMI, LVH prevalence and plasma ADMA levels in the nitrate group were significantly lower than those in the non-nitrate group. BP did not show a significant difference between 12 and 24 weeks in the nitrate group with a reduced need for other medication. Logistic regression analysis showed that nitrate supplementation and SBP reduction were independent risk factors of LVMI change in PD patients after adjusting for age, gender, diabetes history and CCB supplementation. It was concluded that organic nitrates favor regression of LVH in hypertensive patients on chronic peritoneal dialysis, and nitrates may be considered for use before employing the five other antihypertensive agents other than nitrates.

  15. Organic Nitrates Favor Regression of Left Ventricular Hypertrophy in Hypertensive Patients on Chronic Peritoneal Dialysis

    Directory of Open Access Journals (Sweden)

    Han Li

    2013-01-01

    Full Text Available The aim of the study was to evaluate the effect of nitrates on left ventricular hypertrophy (LVH in hypertensive patients on chronic peritoneal dialysis (PD. Sixty-four PD patients with hypertension were enrolled in this study. All patients accepted antihypertensive drugs at baseline. Thirty-two patients (nitrate group took isosorbide mononitrate for 24 weeks. The remaining 32 patients (non-nitrate group took other antihypertensive drugs. Blood pressure (BP, left ventricular mass index (LVMI and plasma asymmetric dimethylarginine (ADMA were monitored. Subjects with normal renal function were included as the control group (n = 30. At baseline, plasma ADMA levels in PD patients were significantly higher than the control group, but there was no significant difference in plasma ADMA levels between the two groups. At the end of the 24-week period, BP, LVMI, LVH prevalence and plasma ADMA levels in the nitrate group were significantly lower than those in the non-nitrate group. BP did not show a significant difference between 12 and 24 weeks in the nitrate group with a reduced need for other medication. Logistic regression analysis showed that nitrate supplementation and SBP reduction were independent risk factors of LVMI change in PD patients after adjusting for age, gender, diabetes history and CCB supplementation. It was concluded that organic nitrates favor regression of LVH in hypertensive patients on chronic peritoneal dialysis, and nitrates may be considered for use before employing the five other antihypertensive agents other than nitrates.

  16. Seasonal resource conditions favor a summertime increase in North Pacific diatom-diazotroph associations.

    Science.gov (United States)

    Follett, Christopher L; Dutkiewicz, Stephanie; Karl, David M; Inomura, Keisuke; Follows, Michael J

    2018-02-15

    In the North Pacific Subtropical Gyre (NPSG), an annual pulse of sinking organic carbon is observed at 4000 m between July and August, driven by large diatoms found in association with nitrogen fixing, heterocystous, cyanobacteria: Diatom-Diazotroph Associations (DDAs). Here we ask what drives the bloom of DDAs and present a simplified trait-based model of subtropical phototroph populations driven by observed, monthly averaged, environmental characteristics. The ratio of resource supply rates favors nitrogen fixation year round. The relative fitness of DDA traits is most competitive in early summer when the mixed layer is shallow, solar irradiance is high, and phosphorus and iron are relatively abundant. Later in the season, as light intensity drops and phosphorus is depleted, the traits of small unicellular diazotrophs become more competitive. The competitive transition happens in August, at the time when the DDA export event occurs. This seasonal dynamic is maintained when embedded in a more complex, global-scale, ecological model, and provides predictions for the extent of the North Pacific DDA bloom. The model provides a parsimonious and testable hypothesis for the stimulation of DDA blooms.

  17. Natural History of Untreated Prostate Specific Antigen Radiorecurrent Prostate Cancer in Men with Favorable Prognostic Indicators

    Directory of Open Access Journals (Sweden)

    Neil E. Martin

    2014-01-01

    Full Text Available Background and Purpose. Life expectancy data could identify men with favorable post-radiation prostate-specific antigen (PSA failure kinetics unlikely to require androgen deprivation therapy (ADT. Materials and Methods. Of 206 men with unfavorable-risk prostate cancer in a randomized trial of radiation versus radiation and ADT, 53 experienced a PSA failure and were followed without salvage ADT. Comorbidity, age and established prognostic factors were assessed for relationship to death using Cox regression analyses. Results. The median age at failure, interval to PSA failure, and PSA doubling time were 76.6 years (interquartile range [IQR]: 71.8–79.3, 49.1 months (IQR: 37.7–87.4, and 25 months (IQR: 13.1–42.8, respectively. After a median follow up of 4.0 years following PSA failure, 45% of men had died, none from prostate cancer and no one had developed metastases. Both increasing age at PSA failure (HR: 1.14; 95% CI: 1.03–1.25; P=0.008 and the presence of moderate to severe comorbidity (HR: 12.5; 95% CI: 3.81–41.0; P2 years following post-radiation PSA failure appear to be good candidates for observation without ADT intervention.

  18. Anthropogenic N deposition slows decay by favoring bacterial metabolism: Insights from metagenomic analyses

    Directory of Open Access Journals (Sweden)

    Zachary B. Freedman

    2016-03-01

    Full Text Available Litter decomposition is an enzymatically-complex process that is mediated by a diverse assemblage of saprophytic microorganisms. It is a globally important biogeochemical process that can be suppressed by anthropogenic N deposition. In a northern hardwood forest ecosystem located in Michigan, USA, 20 years of experimentally increased atmospheric N deposition has reduced forest floor decay and increased soil C storage. Here, we paired extracellular enzyme assays with shotgun metagenomics to assess if anthropogenic N deposition has altered the functional potential of microbial communities inhabiting decaying forest floor. Experimental N deposition significantly reduced the activity of extracellular enzymes mediating plant cell wall decay, which occurred concurrently with changes in the relative abundance of metagenomic functional gene pathways mediating the metabolism of carbohydrates, aromatic compounds, as well as microbial respiration. Moreover, experimental N deposition increased the relative abundance of 50 of the 60 gene pathways, the majority of which were associated with saprotrophic bacteria. Conversely, the relative abundance and composition of fungal genes mediating the metabolism of plant litter was not affected by experimental N deposition. Future rates of atmospheric N deposition have favored saprotrophic soil bacteria, whereas the metabolic potential of saprotrophic fungi appears resilient to this agent of environmental change. Results presented here provide evidence that changes in the functional capacity of saprotrophic soil microorganisms mediate how anthropogenic N deposition increases C storage in soil.

  19. Favorable climate change response explains non-native species' success in Thoreau's woods.

    Science.gov (United States)

    Willis, Charles G; Ruhfel, Brad R; Primack, Richard B; Miller-Rushing, Abraham J; Losos, Jonathan B; Davis, Charles C

    2010-01-26

    Invasive species have tremendous detrimental ecological and economic impacts. Climate change may exacerbate species invasions across communities if non-native species are better able to respond to climate changes than native species. Recent evidence indicates that species that respond to climate change by adjusting their phenology (i.e., the timing of seasonal activities, such as flowering) have historically increased in abundance. The extent to which non-native species success is similarly linked to a favorable climate change response, however, remains untested. We analyzed a dataset initiated by the conservationist Henry David Thoreau that documents the long-term phenological response of native and non-native plant species over the last 150 years from Concord, Massachusetts (USA). Our results demonstrate that non-native species, and invasive species in particular, have been far better able to respond to recent climate change by adjusting their flowering time. This demonstrates that climate change has likely played, and may continue to play, an important role in facilitating non-native species naturalization and invasion at the community level.

  20. Using data from colloid transport experiments to parameterize filtration model parameters for favorable conditions

    Science.gov (United States)

    Kamai, Tamir; Nassar, Mohamed K.; Nelson, Kirk E.; Ginn, Timothy R.

    2017-04-01

    Colloid filtration in porous media spans across many disciplines and includes scenarios such as in-situ bioremediation, colloid-facilitated transport, water treatment of suspended particles and pathogenic bacteria, and transport of natural and engineered nanoparticles in the environment. Transport and deposition of colloid particles in porous media are determined by a combination of complex processes and forces. Given the convoluted physical, chemical, and biological processes involved, and the complexity of porous media in natural settings, it should not come as surprise that colloid filtration theory does not always sufficiently predict colloidal transport, and that there is still a pressing need for improved predictive capabilities. Here, instead of developing the macroscopic equation from pore-scale models, we parametrize the different terms in the macroscopic collection equation through fitting it to experimental data, by optimizing the parameters in the different terms of the equation. This way we combine a mechanistically-based filtration-equation with empirical evidence. The impact of different properties of colloids and porous media are studied by comparing experimental properties with different terms of the correlation equation. This comparison enables insight about different processes that occur during colloid transport and retention under in porous media under favorable conditions, and provides directions for future theoretical developments.

  1. Didactic Strategy to favor the teaching of written texts building forthe Physical Culture field

    Directory of Open Access Journals (Sweden)

    Ana Delia Martínez Bravo

    2017-12-01

    Full Text Available The present study was conducted to contribute to the development of the teaching process of building the functional style texts, so it was established as a general objective: to develop a teaching strategy to promote the teaching of building functional style texts written in the degree course of Physical Culture at the Faculty "Nancy Uranga Romagoza", University Pinar del Río, Cuba. This research favored the qualitative methodology, although it included elements of quantitative methodology. Theoretical methods were used as the historical – logical, analysis and synthesis, induction-deduction, systematization, modeling and structural-systemic; empirical methods such as pedagogical test, documentary, observation and the survey; statistical methods as descriptive statistics. This teaching strategy contributed to the development of the teaching process of building the functional style texts written in athletes of the first year in the degree course of Physical Culture and in this way the curriculum would be considered feasible, flexible and contextualized for the training of professionals.

  2. The cohesion stabilizer sororin favors DNA repair and chromosome segregation during mouse oocyte meiosis.

    Science.gov (United States)

    Huang, Chun-Jie; Yuan, Yi-Feng; Wu, Di; Khan, Faheem Ahmed; Jiao, Xiao-Fei; Huo, Li-Jun

    2017-03-01

    Maintenance and timely termination of cohesion on chromosomes ensures accurate chromosome segregation to guard against aneuploidy in mammalian oocytes and subsequent chromosomally abnormal pregnancies. Sororin, a cohesion stabilizer whose relevance in antagonizing the anti-cohesive property of Wings-apart like protein (Wapl), has been characterized in mitosis; however, the role of Sororin remains unclear during mammalian oocyte meiosis. Here, we show that Sororin is required for DNA damage repair and cohesion maintenance on chromosomes, and consequently, for mouse oocyte meiotic program. Sororin is constantly expressed throughout meiosis and accumulates on chromatins at germinal vesicle (GV) stage/G2 phase. It localizes onto centromeres from germinal vesicle breakdown (GVBD) to metaphase II stage. Inactivation of Sororin compromises the GVBD and first polar body extrusion (PBE). Furthermore, Sororin inactivation induces DNA damage indicated by positive γH2AX foci in GV oocytes and precocious chromatin segregation in MII oocytes. Finally, our data indicate that PlK1 and MPF dissociate Sororin from chromosome arms without affecting its centromeric localization. Our results define Sororin as a determinant during mouse oocyte meiotic maturation by favoring DNA damage repair and chromosome separation, and thereby, maintaining the genome stability and generating haploid gametes.

  3. Operating systems

    CERN Document Server

    Tsichritzis, Dionysios C; Rheinboldt, Werner

    1974-01-01

    Operating Systems deals with the fundamental concepts and principles that govern the behavior of operating systems. Many issues regarding the structure of operating systems, including the problems of managing processes, processors, and memory, are examined. Various aspects of operating systems are also discussed, from input-output and files to security, protection, reliability, design methods, performance evaluation, and implementation methods.Comprised of 10 chapters, this volume begins with an overview of what constitutes an operating system, followed by a discussion on the definition and pr

  4. Operational calculus

    CERN Document Server

    Boehme, Thomas K

    1987-01-01

    Operational Calculus, Volume II is a methodical presentation of operational calculus. An outline of the general theory of linear differential equations with constant coefficients is presented. Integral operational calculus and advanced topics in operational calculus, including locally integrable functions and convergence in the space of operators, are also discussed. Formulas and tables are included.Comprised of four sections, this volume begins with a discussion on the general theory of linear differential equations with constant coefficients, focusing on such topics as homogeneous and non-ho

  5. Schwartz operators

    Science.gov (United States)

    Keyl, M.; Kiukas, J.; Werner, R. F.

    2016-05-01

    In this paper, we introduce Schwartz operators as a non-commutative analog of Schwartz functions and provide a detailed discussion of their properties. We equip them, in particular, with a number of different (but equivalent) families of seminorms which turns the space of Schwartz operators into a Fréchet space. The study of the topological dual leads to non-commutative tempered distributions which are discussed in detail as well. We show, in particular, that the latter can be identified with a certain class of quadratic forms, therefore making operations like products with bounded (and also some unbounded) operators and quantum harmonic analysis available to objects which are otherwise too singular for being a Hilbert space operator. Finally, we show how the new methods can be applied by studying operator moment problems and convergence properties of fluctuation operators.

  6. Atypical pediatric ganglioglioma is common and associated with a less favorable clinical course.

    Science.gov (United States)

    Patibandla, Mohana Rao; Ridder, Thomas; Dorris, Kathleen; Torok, Michelle R; Liu, Arthur K; Handler, Michael H; Stence, Nicholas V; Fenton, Laura Z; Hankinson, Todd C

    2016-01-01

    OBJECT Ganglioglioma (GG) is commonly recognized as a low-grade tumor located in the temporal lobe, often presenting with seizures. Most are amenable to complete resection and are associated with excellent oncological outcome. The authors encountered several GGs in various locations, which seem to have a less favorable clinical course than GGs in the temporal lobe. METHODS The authors performed a single-center retrospective review of all children with a histological diagnosis of GG who were treated at Children's Hospital Colorado between 1997 and 2013. Each tumor was categorized by 2 pediatric neuroradiologists as typical or atypical based on preoperative MRI appearance. Typical lesions were cortically based, within a single cerebral lobe, well-circumscribed, and solid or mixed solid/cystic. The treatment and clinical course of each patient was analyzed. RESULTS Thirty-seven children were identified, with a median age at presentation of 8.2 years and median follow-up of 38.0 months. Eighteen tumors (48.6%) were typical and 19 (51.4%) were atypical. All typical lesions presented with seizures, whereas no atypical lesions did so. Sixteen (88.9%) typical lesions were located in the temporal lobe. In the atypical group, tumor location was variable, including 11 (57.9%) in the brainstem. Death during follow-up was statistically more common in the atypical group (31.6% vs 0%, p = 0.02). Gross-total resection (GTR) was achieved for 15 of 16 typical tumors (93.8%), compared with 3 atypical tumors (15.8%, p Pediatric GG with typical imaging features is associated with excellent rates of GTR and overall survival. Atypical GG is commonly encountered, less amenable to GTR, and associated with a worse outcome. This may relate to anatomical or biological characteristics and merits further investigation.

  7. Does early establishment of favorable oral health behavior influence caries experience at age 5 years?

    Science.gov (United States)

    Wigen, Tove I; Wang, Nina J

    2015-04-01

    The purpose was to study associations between tooth brushing frequency, use of fluoride lozenges and consumption of sugary drinks at 1.5 years of age and having caries experience at 5 years of age. This study was based on data from the Norwegian Mother and Child Cohort Study conducted by the Norwegian Institute of Public Health and by the Public Dental Services. A total of 1095 children were followed from pregnancy to the age of 5 years. Questionnaires regarding oral health behavior were completed by the parents at 1.5 and 5 years of age. Clinical and radiographic examination of the children was performed at the age of 5 years. In multiple logistic regression, having caries experience at 5 years of age was associated with; at 1.5 years of age having the teeth brushed less than twice daily (OR = 2.1, CI = 1.3-3.6) and being offered sugary drinks at least once a week (OR = 1.8, CI = 1.1-2.9) when controlled for family characteristics and oral health behavior at 5 years of age. Tooth brushing frequency and consumption of sugary drinks in early childhood were related to caries development during pre-school age, independent of family characteristics and oral health behavior at 5 years of age. The results indicate that early established habits regarding tooth brushing and consumption of sugary drinks have long-term effects on caries development. Parents encountering difficulties in establishing favorable oral health behavior in children's first years of life should receive special attention from health personnel.

  8. Resection of ictal high-frequency oscillations leads to favorable surgical outcome in pediatric epilepsy

    Science.gov (United States)

    Fujiwara, Hisako; Greiner, Hansel M.; Lee, Ki Hyeong; Holland-Bouley, Katherine D.; Seo, Joo Hee; Arthur, Todd; Mangano, Francesco T.; Leach, James L.; Rose, Douglas F.

    2012-01-01

    Summary Purpose Intracranial electroencephalography (EEG) is performed as part of an epilepsy surgery evaluation when noninvasive tests are incongruent or the putative seizure-onset zone is near eloquent cortex. Determining the seizure-onset zone using intracranial EEG has been conventionally based on identification of specific ictal patterns with visual inspection. High-frequency oscillations (HFOs, >80 Hz) have been recognized recently as highly correlated with the epileptogenic zone. However, HFOs can be difficult to detect because of their low amplitude. Therefore, the prevalence of ictal HFOs and their role in localization of epileptogenic zone on intracranial EEG are unknown. Methods We identified 48 patients who underwent surgical treatment after the surgical evaluation with intracranial EEG, and 44 patients met criteria for this retrospective study. Results were not used in surgical decision making. Intracranial EEG recordings were collected with a sampling rate of 2,000 Hz. Recordings were first inspected visually to determine ictal onset and then analyzed further with time-frequency analysis. Forty-one (93%) of 44 patients had ictal HFOs determined with time-frequency analysis of intracranial EEG. Key Findings Twenty-two (54%) of the 41 patients with ictal HFOs had complete resection of HFO regions, regardless of frequency bands. Complete resection of HFOs (n = 22) resulted in a seizure-free outcome in 18 (82%) of 22 patients, significantly higher than the seizure-free outcome with incomplete HFO resection (4/19, 21%). Significance Our study shows that ictal HFOs are commonly found with intracranial EEG in our population largely of children with cortical dysplasia, and have localizing value. The use of ictal HFOs may add more promising information compared to interictal HFOs because of the evidence of ictal propagation and followed by clinical aspect of seizures. Complete resection of HFOs is a favorable prognostic indicator for surgical outcome. PMID

  9. Greenland englacial drainage: conditions favoring water transport through a fractured aquifer

    Science.gov (United States)

    Creyts, T. T.; Fountain, A. G.

    2015-12-01

    Recently, the subglacial hydrology of glaciers and ice sheets has garnered intense interest because of its effects on ice sliding and potential ice sheet responses leading to sea level rise. Less attention has focused on the englacial water system that connects surface meltwater sources to the basal drainage system. Observations of englacial drainage have revealed diametrically opposed behaviors, so that understanding the role of the englacial system is critical to developing knowledge of ice sheet responses. The englacial connections either enhance or limit subglacial processes, including sliding. Some observations show cases where water drainage is mainly through an englacial system of fractures so that water flow at the bed is stunted. Other observations show static englacial water systems that play little role in drainage with primary drainage routes being along the bed. Here, we use a thermomechanical model of englacial water flow to understand the interaction between ice and water along these connections. We assume that water flow is through a series of connected fractures analogous to crevassed Greenland outlet glaciers. The fractures are modified by ice flow, and freezing and melting of the water system. Simple mathematical analyses show trade offs between closure rates and melting rates that determine the englacial flowpaths. From numerical experiments, we show that the dominance of englacial flow follows the locations of both bed overdeepenings and areas where the basal water system is compressed dynamically. The preponderance of overdeependenings in Greenland suggests that englacial systems may be favored in critical areas of ice sheet flow. We conclude by relating the insights from the analytic and numerical results to the broad scale patterns of change of the Greenland Ice Sheet.

  10. TIMP-3 expression associates with malignant behaviors and predicts favorable survival in HCC.

    Directory of Open Access Journals (Sweden)

    Xuefeng Gu

    Full Text Available The tissue inhibitors of metalloproteinases (TIMPs are proteins that specifically inhibit the proteolytic activity of the matrix metalloproteinases (MMPs. TIMP-3, the only member of the TIMPs that can tightly bind to the extracellular matrix, has been identified as a unique tumor suppressor that demonstrates the ability to inhibit tumor angiogenesis, invasion, and metastasis. This study aimed to detect the expression of TIMP-3 in hepatocellular carcinoma (HCC and investigate the association between TIMP-3 expression and its clinicopathological significance in HCC patients. In the current study, reverse transcription-polymerase chain reaction (RT-PCR and Western blotting of HCC cell lines and one-step quantitative reverse transcription PCR (qPCR and immunohistochemistry (IHC analyses in HCC tissues were performed, to characterize the TIMP-3 expression. Kaplan-Meier survival and Cox regression analyses were utilized to evaluate the prognosis of 101 HCC patients. The results showed that the expression of TIMP-3 in HCC was significantly decreased relative to that of non-cancerous cells and tissues. Furthermore, the TIMP-3 expression was statistically associated with malignant behaviors of HCC, including portal vein invasion (p = 0.036 and lymph node metastasis (p = 0.030. Cox regression analysis revealed that TIMP-3 expression was an independent prognostic factor for disease-free survival (p = 0.039 and overall survival (p = 0.049. These data indicate that TIMP-3 expression is a valuable prognostic biomarker for HCC and that TIMP-3 expression suggests a favorable prognosis for HCC patients.

  11. Aquatic pollution may favor the success of the invasive species A. franciscana

    Energy Technology Data Exchange (ETDEWEB)

    Varó, I., E-mail: inma@iats.csic.es [Instituto de Acuicultura Torre de la Sal (IATS-CSIC), Ribera de Cabanes, Castellón 12595 Spain (Spain); Redón, S. [Instituto de Acuicultura Torre de la Sal (IATS-CSIC), Ribera de Cabanes, Castellón 12595 Spain (Spain); Garcia-Roger, E.M. [Cavanilles Institute of Biodiversity and Evolutionary Biology, University of Valencia, Burjassot (Spain); Amat, F.; Guinot, D. [Instituto de Acuicultura Torre de la Sal (IATS-CSIC), Ribera de Cabanes, Castellón 12595 Spain (Spain); Serrano, R. [Research Institute for Pesticides and Water (IUPA), Avda. Sos Baynat, s/n. University Jaume I, Castellón 12071 (Spain); Navarro, J.C. [Instituto de Acuicultura Torre de la Sal (IATS-CSIC), Ribera de Cabanes, Castellón 12595 Spain (Spain)

    2015-04-15

    Highlights: • Artemia species display an elevated tolerance to high ranges of chlorpyrifos. • A. franciscana survived better and its fecundity was less affected by chlorpyrifos. • The higher fecundity of A. franciscana is a selective advantage in colonization processes. • Higher survival and biological fitness in A. franciscana indicate out-competitive advantages. - Abstract: The genus Artemia consists of several bisexual and parthenogenetic sibling species. One of them, A. franciscana, originally restricted to the New World, becomes invasive when introduced into ecosystems out of its natural range of distribution. Invasiveness is anthropically favored by the use of cryptobiotic eggs in the aquaculture and pet trade. The mechanisms of out-competition of the autochthonous Artemia by the invader are still poorly understood. Ecological fitness may play a pivotal role, but other underlying biotic and abiotic factors may contribute. Since the presence of toxicants in hypersaline aquatic ecosystems has been documented, our aim here is to study the potential role of an organophosphate pesticide, chlorpyrifos, in a congeneric mechanism of competition between the bisexual A. franciscana (AF), and one of the Old World parthenogenetic siblings, A. parthenogenetica (PD). For this purpose we carried out life table experiments with both species, under different concentrations of the toxicant (0.1, 1 and 5 μg/l), and analyzed the cholinesterase inhibition at different developmental stages. The results evidence that both, AF and PD, showed an elevated tolerance to high ranges of chlorpyrifos, but AF survived better and its fecundity was less affected by the exposure to the pesticide than that of PD. The higher fecundity of AF is a selective advantage in colonization processes leading to its establishment as NIS. Besides, under the potential selective pressure of abiotic factors, such as the presence of toxicants, its higher resistance in terms of survival and biological

  12. SCD5 restored expression favors differentiation and epithelial-mesenchymal reversion in advanced melanoma.

    Science.gov (United States)

    Puglisi, Rossella; Bellenghi, Maria; Pontecorvi, Giada; Gulino, Alessandro; Petrini, Marina; Felicetti, Federica; Bottero, Lisabianca; Mattia, Gianfranco; Carè, Alessandra

    2018-01-26

    Our previous data supported a role for the Stearoyl-CoA desaturase (SCD5) in protection against malignancy, whereby it appears to functionally modify tumor stroma impairing tumor spread. SCD5 is significantly expressed in primary melanoma, but becomes barely detectable at tumor advanced stages. Looking for the regulatory mechanisms underlying SCD5 reduced expression during melanoma progression, we demonstrated a significantly lower stability of SCD5 protein as well as the direct targeting of SCD5 mRNA by the oncogenic miR-221&222 in metastatic cell lines. Moreover, our results indicated the existence of a negative feedback loop between SCD5 and miR-221&222, in good agreement with their opposite functions. Also, we showed how SCD5 re-expression and the direct supplementation of its main product oleic acid (OA) can drive advanced melanoma cell lines toward differentiation and reversion of the epithelial-mesenchymal (EMT)-like process, eventually inducing a less malignant phenotype. Indeed, SCD5 re-established the sensitivity to all-trans retinoic acid in A375M metastatic melanoma, associated with increased levels of Tyrosinase, melanin production and reduced proliferation. As evidenced by the correct modulation of some key transcription factors, SCD5 managed by favoring a partial mesenchymal-to-epithelial (MET) transition in in vitro studies. Interestingly, a more complete MET, including E-cadherin re-expression correctly localized at cell membranes, was obtained in in vivo xenograft models, thus indicating the requirement of direct contacts between tumor cells and the surrounding microenvironment as well as the presence of some essential factors for SCD5 complete function.

  13. Chronic Voluntary Ethanol Consumption Induces Favorable Ceramide Profiles in Selectively Bred Alcohol-Preferring (P Rats.

    Directory of Open Access Journals (Sweden)

    Jessica Godfrey

    achieved by alcohol-preferring P rats as a result of chronic voluntary exposure may have favorable vs. detrimental effects on lipid profiles in this genetic line, consistent with data supporting beneficial cardioprotective and neuroprotective effects of moderate ethanol consumption.

  14. Chronic Voluntary Ethanol Consumption Induces Favorable Ceramide Profiles in Selectively Bred Alcohol-Preferring (P) Rats.

    Science.gov (United States)

    Godfrey, Jessica; Jeanguenin, Lisa; Castro, Norma; Olney, Jeffrey J; Dudley, Jason; Pipkin, Joseph; Walls, Stanley M; Wang, Wei; Herr, Deron R; Harris, Greg L; Brasser, Susan M

    2015-01-01

    alcohol-preferring P rats as a result of chronic voluntary exposure may have favorable vs. detrimental effects on lipid profiles in this genetic line, consistent with data supporting beneficial cardioprotective and neuroprotective effects of moderate ethanol consumption.

  15. Somatic mutations favorable to patient survival are predominant in ovarian carcinomas.

    Directory of Open Access Journals (Sweden)

    Wensheng Zhang

    Full Text Available Somatic mutation accumulation is a major cause of abnormal cell growth. However, some mutations in cancer cells may be deleterious to the survival and proliferation of the cancer cells, thus offering a protective effect to the patients. We investigated this hypothesis via a unique analysis of the clinical and somatic mutation datasets of ovarian carcinomas published by the Cancer Genome Atlas. We defined and screened 562 macro mutation signatures (MMSs for their associations with the overall survival of 320 ovarian cancer patients. Each MMS measures the number of mutations present on the member genes (except for TP53 covered by a specific Gene Ontology (GO term in each tumor. We found that somatic mutations favorable to the patient survival are predominant in ovarian carcinomas compared to those indicating poor clinical outcomes. Specially, we identified 19 (3 predictive MMSs that are, usually by a nonlinear dose-dependent effect, associated with good (poor patient survival. The false discovery rate for the 19 "positive" predictors is at the level of 0.15. The GO terms corresponding to these MMSs include "lysosomal membrane" and "response to hypoxia", each of which is relevant to the progression and therapy of cancer. Using these MMSs as features, we established a classification tree model which can effectively partition the training samples into three prognosis groups regarding the survival time. We validated this model on an independent dataset of the same disease (Log-rank p-value < 2.3 × 10(-4 and a dataset of breast cancer (Log-rank p-value < 9.3 × 10(-3. We compared the GO terms corresponding to these MMSs and those enriched with expression-based predictive genes. The analysis showed that the GO term pairs with large similarity are mainly pertinent to the proteins located on the cell organelles responsible for material transport and waste disposal, suggesting the crucial role of these proteins in cancer mortality.

  16. Aquatic pollution may favor the success of the invasive species A. franciscana

    International Nuclear Information System (INIS)

    Varó, I.; Redón, S.; Garcia-Roger, E.M.; Amat, F.; Guinot, D.; Serrano, R.; Navarro, J.C.

    2015-01-01

    Highlights: • Artemia species display an elevated tolerance to high ranges of chlorpyrifos. • A. franciscana survived better and its fecundity was less affected by chlorpyrifos. • The higher fecundity of A. franciscana is a selective advantage in colonization processes. • Higher survival and biological fitness in A. franciscana indicate out-competitive advantages. - Abstract: The genus Artemia consists of several bisexual and parthenogenetic sibling species. One of them, A. franciscana, originally restricted to the New World, becomes invasive when introduced into ecosystems out of its natural range of distribution. Invasiveness is anthropically favored by the use of cryptobiotic eggs in the aquaculture and pet trade. The mechanisms of out-competition of the autochthonous Artemia by the invader are still poorly understood. Ecological fitness may play a pivotal role, but other underlying biotic and abiotic factors may contribute. Since the presence of toxicants in hypersaline aquatic ecosystems has been documented, our aim here is to study the potential role of an organophosphate pesticide, chlorpyrifos, in a congeneric mechanism of competition between the bisexual A. franciscana (AF), and one of the Old World parthenogenetic siblings, A. parthenogenetica (PD). For this purpose we carried out life table experiments with both species, under different concentrations of the toxicant (0.1, 1 and 5 μg/l), and analyzed the cholinesterase inhibition at different developmental stages. The results evidence that both, AF and PD, showed an elevated tolerance to high ranges of chlorpyrifos, but AF survived better and its fecundity was less affected by the exposure to the pesticide than that of PD. The higher fecundity of AF is a selective advantage in colonization processes leading to its establishment as NIS. Besides, under the potential selective pressure of abiotic factors, such as the presence of toxicants, its higher resistance in terms of survival and biological

  17. Vaccination Against Human Papilloma Viruses Leads to a Favorable Cytokine Profile of Specific T Cells.

    Science.gov (United States)

    Luckau, Stefanie; Wehrs, Tim P; Brandau, Sven; Horn, Peter A; Lindemann, Monika

    2016-10-01

    Several human papilloma viruses (HPV) are known to cause malignant transformation. The high-risk type HPV 16 is associated with cervical carcinoma and head and neck squamous cell carcinoma. HPV 16-positive tumor cells exclusively carry the HPV 16 oncogenes E6 and E7. These oncogenes appear as excellent targets for an adoptive immunotherapy. We here addressed the question whether specific T cells from HPV-vaccinated healthy volunteers could be especially suitable for an HPV-specific cellular immunotherapy. Of note, vaccines contain HPV 16. To quantify HPV 16 E6-specific and E7-specific cells, enzyme-linked immunospot assays to measure interferon-γ (IFN-γ) and interleukin-10 (Th1-Th2 balance) and the secretion of the cytotoxic molecules granzyme B and perforin have been optimized. The frequency of peripheral blood mononuclear cells secreting IFN-γ and perforin was significantly (P<0.05) increased in HPV-vaccinated versus nonvaccinated volunteers. Overall, however, the median frequency of HPV 16-specific cells with a favorable secretion profile (Th1 balanced and cytotoxic) was low even in vaccinated volunteers (IFN-γ: 0.0018% and 0.0023%, perforin: 0.01% and 0.0087% for E6-specific and E7-specific cells, respectively). But some vaccinated volunteers showed up to 0.1% HPV-specific, IFN-γ or perforin-secreting cells. In conclusion, our data suggest that vaccinated volunteers are superior to nonvaccinated donors for HPV-specific cellular cancer immunotherapy.

  18. Geology and uranium favorability of the Sonora Pass region, Alpine and Tuolumne Counties, California

    Energy Technology Data Exchange (ETDEWEB)

    Rapp, J.S.; Short, W.O.

    1981-06-01

    Uranium mineralization at the Juniper Mine is restricted to host rocks of the Relief Peak Formation and is most common in coarse-grained lithic sandstone, conglomerate, and lithic wacke. The richest beds contain as much as 0.5% U/sub 3/O/sub 8/. Uranium is present as coffinite, uraninite, and unidentified minerals. Thorium/uranium ratios are generally low and erratic. Equivalent uranium determinations are low in comparison with chemical uranium values, indicating that uranium mineralization of the Juniper Mine is geologically young. Core drilling at 16 localities shows that widely separated exposures of the Relief Peak Formation have very similar lithology, geochemistry, and stratigraphy. Some sections are similar to the Juniper Mine section. Core from the bottom of drill hole SP-1 contains 83 ppM uranium, the greatest known concentration outside the mine area. Significant uranium deposits may be concealed beneath the thick Tertiary volcanic cover of the region. The quartz latitic Eureka Valley Tuff is fairly widespread in east-central California and western Nevada. It contains 12 to 14 ppM uranium and stratigraphically overlies the Relief Peak Formation. It is permeable and contains abundant alkali metals and volcanic glass. Because of its petrology, geochemistry, and position, this formation is the most likely source for uranium mineralization of the Sonora Pass region. It should be examined as a potential source rock in other areas with special regard to its relationship to carbonaceous sedimentary formations. The uraniferous granite pegmatitite dike that crops out in the Niagara Creek area appears too small to be a significant source rock. The most favorable rocks in the Sonora Pass region occur near the Juniper Mine and west of it, in the Dardanelles, the Whittakers Dardanelles, and the area of the Big Meadow Quadrangle. Potential uranium host rocks crop out in areas along the crest of the Sierra Nevada from Lake Tahoe to Yosemite.

  19. Geology and uranium favorability of the Sonora Pass region, Alpine and Tuolumne Counties, California

    International Nuclear Information System (INIS)

    Rapp, J.S.; Short, W.O.

    1981-06-01

    Uranium mineralization at the Juniper Mine is restricted to host rocks of the Relief Peak Formation and is most common in coarse-grained lithic sandstone, conglomerate, and lithic wacke. The richest beds contain as much as 0.5% U 3 O 8 . Uranium is present as coffinite, uraninite, and unidentified minerals. Thorium/uranium ratios are generally low and erratic. Equivalent uranium determinations are low in comparison with chemical uranium values, indicating that uranium mineralization of the Juniper Mine is geologically young. Core drilling at 16 localities shows that widely separated exposures of the Relief Peak Formation have very similar lithology, geochemistry, and stratigraphy. Some sections are similar to the Juniper Mine section. Core from the bottom of drill hole SP-1 contains 83 ppM uranium, the greatest known concentration outside the mine area. Significant uranium deposits may be concealed beneath the thick Tertiary volcanic cover of the region. The quartz latitic Eureka Valley Tuff is fairly widespread in east-central California and western Nevada. It contains 12 to 14 ppM uranium and stratigraphically overlies the Relief Peak Formation. It is permeable and contains abundant alkali metals and volcanic glass. Because of its petrology, geochemistry, and position, this formation is the most likely source for uranium mineralization of the Sonora Pass region. It should be examined as a potential source rock in other areas with special regard to its relationship to carbonaceous sedimentary formations. The uraniferous granite pegmatitite dike that crops out in the Niagara Creek area appears too small to be a significant source rock. The most favorable rocks in the Sonora Pass region occur near the Juniper Mine and west of it, in the Dardanelles, the Whittakers Dardanelles, and the area of the Big Meadow Quadrangle. Potential uranium host rocks crop out in areas along the crest of the Sierra Nevada from Lake Tahoe to Yosemite

  20. Professional development programs in health promotion: tools and processes to favor new practices.

    Science.gov (United States)

    Torres, Sara; Richard, Lucie; Guichard, Anne; Chiocchio, François; Litvak, Eric; Beaudet, Nicole

    2017-06-01

    Developing innovative interventions that are in sync with a health promotion paradigm often represents a challenge for professionals working in local public health organizations. Thus, it is critical to have both professional development programs that favor new practices and tools to examine these practices. In this case study, we analyze the health promotion approach used in a pilot intervention addressing children's vulnerability that was developed and carried out by participants enrolled in a public health professional development program. More specifically, we use a modified version of Guichard and Ridde's (Une grille d'analyse des actions pour lutter contre les inégalités sociales de santé. In Potvin, L., Moquet, M.-J. and Jones, C. M. (eds), Réduire les Inégalités Sociales en Santé. INPES, Saint-Denis Cedex, pp. 297-312, 2010) analytical grid to assess deductively the program participants' use of health promotion practices in the analysis and planning, implementation, evaluation, sustainability and empowerment phases of the pilot intervention. We also seek evidence of practices involving (empowerment, participation, equity, holism, an ecological approach, intersectorality and sustainability) in the intervention. The results are mixed: our findings reveal evidence of the application of several dimensions of health promotion (equity, holism, an ecological approach, intersectorality and sustainability), but also a lack of integration of two key dimensions; that is, empowerment and participation, during various phases of the pilot intervention. These results show that the professional development program is associated with the adoption of a pilot intervention integrating multiple but not all dimensions of health promotion. We make recommendations to facilitate a more complete integration. This research also shows that the Guichard and Ridde grid proves to be a thorough instrument to document the practices of participants. © The Author 2015. Published by

  1. Spacecraft operations

    CERN Document Server

    Sellmaier, Florian; Schmidhuber, Michael

    2015-01-01

    The book describes the basic concepts of spaceflight operations, for both, human and unmanned missions. The basic subsystems of a space vehicle are explained in dedicated chapters, the relationship of spacecraft design and the very unique space environment are laid out. Flight dynamics are taught as well as ground segment requirements. Mission operations are divided into preparation including management aspects, execution and planning. Deep space missions and space robotic operations are included as special cases. The book is based on a course held at the German Space Operation Center (GSOC).

  2. Favorable Vascular Actions of Angiotensin-(1-7) in Human Obesity.

    Science.gov (United States)

    Schinzari, Francesca; Tesauro, Manfredi; Veneziani, Augusto; Mores, Nadia; Di Daniele, Nicola; Cardillo, Carmine

    2018-01-01

    Obese patients have vascular dysfunction related to impaired insulin-stimulated vasodilation and increased endothelin-1-mediated vasoconstriction. In contrast to the harmful vascular actions of angiotensin (Ang) II, the angiotensin-converting enzyme 2 product Ang-(1-7) has shown to exert cardiovascular and metabolic benefits in experimental models through stimulation of the Mas receptor. We, therefore, examined the effects of exogenous Ang-(1-7) on vasodilator tone and endothelin-1-dependent vasoconstriction in obese patients. Intra-arterial infusion of Ang-(1-7) (10 nmol/min) resulted in significant increase in unstimulated forearm flow ( P =0.03), an effect that was not affected by the Mas receptor antagonist A779 (10 nmol/min; P >0.05). In the absence of hyperinsulinemia, however, forearm flow responses to graded doses of acetylcholine and sodium nitroprusside were not different during Ang-(1-7) administration compared with saline (both P >0.05). During infusion of regular insulin (0.15 mU/kg per minute), by contrast, endothelium-dependent vasodilator response to acetylcholine was significantly enhanced by Ang-(1-7) ( P =0.04 versus saline), whereas endothelium-independent response to sodium nitroprusside was not modified ( P =0.91). Finally, Ang-(1-7) decreased the vasodilator response to endothelin A receptor blockade (BQ-123; 10 nmol/min) compared with saline (6±1% versus 93±17%; P <0.001); nitric oxide inhibition by l- N -monomethylarginine (4 µmol/min) during concurrent endothelin A antagonism resulted in similar vasoconstriction in the absence or presence of Ang-(1-7 Ang-(1-7) ( P =0.69). Our findings indicate that in obese patients Ang-(1-7) has favorable effects not only to improve insulin-stimulated endothelium-dependent vasodilation but also to blunt endothelin-1-dependent vasoconstrictor tone. These findings provide support for targeting Ang-(1-7) to counteract the hemodynamic abnormalities of human obesity. © 2017 American Heart Association, Inc.

  3. Land use dynamics in favorable and unfavorable areas of southwest Germany

    Science.gov (United States)

    Henkner, Jessica; Ahlrichs, Jan; Knopf, Thomas; Scholten, Thomas; Kühn, Peter

    2017-04-01

    Since the Neolithic Revolution and the beginning of agriculture in central Europe about 7.500 a ago human influence on the environment is increasing. Human activities created a cultural landscape during the Holocene, which led to quasi-natural relief formation. Colluvial deposits are the correlate sediments of human induced soil erosion on slopes and depict an excellent archive for land use and landscape history. The present study combines pedological, archaeological and palynological knowledge with AMS 14C and luminescence datings to build up a chronostratigraphy of colluvial deposits, thereby allowing the reconstruction of past land use and settlement dynamics in the Baar and the Black Forest (SW Germany). Compared with Black Forest the Baar is a favorable area for agricultural land use, where seven main phases of colluvial deposition could be detected. Increased colluviation, and thus land use intensity, took place during the younger Neolithic ( 3700 BCE), the early to middle Bronze Age ( 1400 BCE), the Iron Age ( 500 BCE), the Roman Empire ( 200 CE) and in three phases from the High Middle Ages onwards ( 1100 CE, 1300 CE, 1600 CE). The Black Forest low mountain range is an unfavorable area characterized by low temperatures, high precipitation and steep slopes. Nevertheless, human influence dates back to the Neolithic in the Black Forest. Minor colluvial deposition phases were detected before the Middle Ages and increased formation of colluvial deposits during the High Middle Ages ( 1100 CE) and the Modern Times (>1500 CE). This colluvial stratigraphy shows an intense land use of the Black Forest area from the Middle Ages onwards. The different land use dynamics in the Baar area compared to the Black Forest will be discussed against the paleoenvironmental conditions reconstructed from different archives. It is to analyze whether climate was the main determining factor for the settlement pattern in time and space or if there were other factors responsible. Such

  4. Translation-rotation decoupling of tracers of locally favorable structures in glass-forming liquids

    Science.gov (United States)

    Park, Yoonjae; Kim, Jeongmin; Sung, Bong June

    2017-09-01

    Particles in glass-forming liquids may form domains of locally favorable structures (LFSs) upon supercooling. Whether and how the LFS domains would relate to the slow relaxation of the glass-forming liquids have been issues of interest. In this study, we employ tracers of which structures resemble the LFS domains in Wahnström and Kob-Andersen (KA) glass-forming liquids and investigate the translation-rotation decoupling of the tracers. We find that the tracer structure affects how the translation and the rotation of tracers decouple and that information on the local mobility around the LFS domains may be gleaned from the tracer dynamics. According to the Stokes-Einstein relation and the Debye-Stokes-Einstein relation, the ratio of the translational (DT) and rotational (DR) diffusion coefficients is expected to be a constant over a range of T /η , where η and T denote the medium viscosity and temperature, respectively. In supercooled liquids and glasses, however, DT and DR decouple due to dynamic heterogeneity, thus DT/DR not being constant any more. In Wahnström glass-forming liquids, icosahedron LFS domains are the most long-lived ones and the mobility of neighbor particles around the icosahedron LFS domain is suppressed. We find from our simulations that the icosahedron tracers, similar in size and shape to the icosahedron LFS domains, experience drastic translation-rotation decoupling upon cooling. The local mobility of liquid particles around the icosahedron tracers is also suppressed significantly. On the other hand, tracers of FCC and HCP structures do not show translation-rotation decoupling in the Wahnström liquid. In KA glass-forming liquids, bicapped square antiprism LFS domains are the most long-lived LFS domains but are not correlated significantly with the local mobility. We find from our simulations that DT and DR of bicapped square antiprism tracers, also similar in size and shape to the bicapped square antiprism LFS domains, do not decouple

  5. «En favor de las víctimas de la guerra»

    Directory of Open Access Journals (Sweden)

    Robles Muñoz, Cristóbal

    2009-12-01

    Full Text Available Informal representation given to Cardinal Gomá in December 1936, sending Ildebrando Antoniutti as apostolic delegate in humanitarian mission in July, remained at its lowest level relations between the Holy See with the government of Franco. The situation changed in 1937. The nuncio Gaetano Cicognani did not arrive until June 1938. Discrete steps of a secret diplomacy advised in September 1937 to formalize the relationship, at its lowest. Antoniutti and Pablo de Churruca were named Responsible of Affairs, in Burgos, and to the Holy See, in a respective way. The collective letter of the bishops helped to improve the image of «national» Spain before the Catholics in other countries. The doctrinal position in which these facts were inserted was fixed at three encyclicals published in March 1937. They condemned the religious persecution of communism, nazism and the fear of a desire to runaway of the persecution forgiving people and fighting for justice for the working classesLa representación oficiosa dada al cardenal Gomá en diciembre de 1936, el envío Ildebrando Antoniutti como delegado apostólico en julio en misión humanitaria, mantuvieron bajo mínimos las relaciones de la Santa Sede con el Gobierno de Franco. La situación no cambió en 1937. El nuncio Gaetano Cicognani no llegó hasta junio de 1938. Los pasos discretos de una diplomacia secreta aconsejaron en septiembre de 1937 formalizar las relaciones, en su nivel más bajo. Antoniutti y Pablo de Churruca fueron nombrados encargados de negocios, en Burgos y ante la Santa Sede. La carta colectiva de los obispos ayudó a mejorar la imagen los nacionales ante los católicos de otros países. La posición doctrinal en que se insertan estos hechos quedó fijada en las tres encíclicas publicadas en marzo de 1937. En ella se denuncia la persecución religiosa del comunismo, el temor al nazismo y el deseo de salir de la persecución personando y luchando por la justicia a favor de las clases

  6. Favored subjects and psychosocial needs in music therapy in terminally ill cancer patients: a content analysis.

    Science.gov (United States)

    Preissler, Pia; Kordovan, Sarah; Ullrich, Anneke; Bokemeyer, Carsten; Oechsle, Karin

    2016-05-12

    Research has shown positive effects of music therapy on the physical and mental well-being of terminally ill patients. This study aimed to identify favored subjects and psychosocial needs of terminally ill cancer patients during music therapy and associated factors. Forty-one Patients receiving specialized inpatient palliative care prospectively performed a music therapy intervention consisting of at least two sessions (total number of sessions: 166; per patient average: 4, range, 2-10). Applied music therapy methods and content were not pre-determined. Therapeutic subjects and psychosocial needs addressed in music therapy sessions were identified from prospective semi-structured "field notes" using qualitative content analysis. Patient- and treatment-related characteristics as well as factors related to music and music therapy were assessed by questionnaire or retrieved from medical records. Seven main categories of subjects were identified: "condition, treatment, further care", "coping with palliative situation", "emotions and feelings", "music and music therapy", "biography", "social environment", and "death, dying, and spiritual topics". Patients addressed an average of 4.7 different subjects (range, 1-7). Some subjects were associated with gender (p = .022) and prior impact of music in patients' life (p = .012). The number of subjects per session was lower when receptive music therapy methods were used (p = .040). Psychosocial needs were categorized into nine main dimensions: "relaxing and finding comfort", "communication and dialogue", "coping and activation of internal resources", "activity and vitality", "finding expression", "sense of self and reflection", "finding emotional response", "defocusing and diversion", and "structure and hold". Patients expressed an average of 4.9 psychosocial needs (range, 1-8). Needs were associated with age, parallel art therapy (p = .010), role of music in patient's life (p = .021), and the applied music

  7. A combination of extreme environmental conditions favor the prevalence of Endospore-forming Firmicutes

    Directory of Open Access Journals (Sweden)

    Sevasti Filippidou

    2016-11-01

    for which active growth could be expected, and phylotypes that are most likely in the state of endospores, in all the sites. In summary, our results suggest that diversified survival strategies, including sporulation and metabolic adaptations, explain the biological success of EFF in geothermal and natural springs, and that multiple extreme environmental factors favor the prevalence of EFF.

  8. Taipower's operational experience

    International Nuclear Information System (INIS)

    Hsu, Huei-Hsiung; Lin, M.M.H.; Chiang, Min-Kuang

    1988-01-01

    Taiwan Power Company currently operates four BWRs and two PWRs at three different sites. Chinshan NPS is a twin 636 MWe General Electric BWR-4 reactors with Mark I containment and Kuosheng NPS is a twin 985 MWe General Electric BWR-6 reactors with Mark III contaiqment. They are both located at northern sea coast of Taiwan. Maanshan NPS, sited in the southern tip of Taiwan, has two Westinghouse PWR units with 951 MWe output each. After a series of betterments, the water qualities of Chinshan, Kuosheng and Maashan MPSs are now controlled in satisfactory condition. The betterments made in the Chinshan NPS are: dreasing the elbow's quantity and adoption of the smaller piping and control valves for easy flow control of URC; material improvement for RWCU pump mechanical seal for favorable RWCU operation; and con-demin resin ratio alteration. HWC is now planned to be adopted to minimize the IGSCC. The betterments made in the Huosheng NPS include: resin transfer improvement for con-demin; resin type alteration; non-regenerative adoption; and RWCU V/V checking and reparing, and improvement for precoat medium and procedure. Those made in the Maashan NPS are: betterment concerning the problem of dissolved oxygen, betterment for the TOC of make up system, and strengthening of the internal structure of condensate polisher, and operating concept's settlement. (Nogami, K.)

  9. Surgery in metastatic breast cancer: patients with a favorable profile seem to have the most benefit from surgery.

    Science.gov (United States)

    Rashaan, Z M; Bastiaannet, E; Portielje, J E A; van de Water, W; van der Velde, S; Ernst, M F; van de Velde, C J H; Liefers, G J

    2012-01-01

    About 3-10% of breast cancer patients have distant metastases (Stage IV) at initial presentation; standard treatment (in the Netherlands) of these patients consists of palliative systemic therapy. However, retrospective studies have shown an improved survival in patients who received surgery for their primary tumor. The aim of this study was to assess characteristics associated with surgical treatment and to determine the impact on survival in women with stage IV breast cancer. A cohort of women with a diagnosis of breast cancer and concomitant distant metastases was retrospectively studied. Patient characteristics, treatment and survival distilled from medical files were evaluated using univariate and multivariable analysis. Of 171 patients included in this analysis, 59 underwent surgery. In multivariable analysis lower age, no medication use, lower clinical T-stage and lower grade were associated with receiving surgery. In 21 of the 59 patients (35%) who received surgery it was unknown at the time of surgery that the patient had metastatic disease. Stratified survival analyses showed an association between surgery and improved survival for young patients (HR 0.3; p = 0.02), without comorbidity (HR 0.4; p = 0.002), with no medication use (HR 0.5; p = 0.009), with a small tumor (HR 0.4; p = 0.01), no regional lymph node involvement (HR 0.4; p = 0.01), with positive Estrogen (HR 0.6; p = 0.02) or Progesterone receptor (HR 0.4; p = 0.03) and with only visceral metastases (HR 0.5; p = 0.03). In multivariable analyses, younger patients and patients without comorbidity that received surgery had an increased survival (HR 0.3; p = 0.03 and HR 0.5; p = 0.03, respectively). This study showed that patients with the most favorable profile receive local surgery and that a survival gain for operated patients was seen in young patients and in patients without comorbidity. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. Accelerator operations

    International Nuclear Information System (INIS)

    Anon.

    1979-01-01

    Operations of the SuperHILAC, the Bevatron/Bevalac, and the 184-inch Synchrocyclotron during the period from October 1977 to September 1978 are discussed. These include ion source development, accelerator facilities, the Heavy Ion Spectrometer System, and Bevelac biomedical operations

  11. Operational Sequencing

    DEFF Research Database (Denmark)

    Nielsen, Thomas Rosendal; Hustvedt, Kjersti

    2017-01-01

    by Bakhtinian theory, Brian Edmiston developed a solution to this in the 1990s: the principle of ‘dialogic sequencing’. Aiming to escape the conflict between relativism and absolutism, we present an alternative to Edmiston’s approach, based on Niklas Luhmann’s theory of ‘operational closure’: operational...

  12. Operating Systems

    Indian Academy of Sciences (India)

    M Suresh Babu is currently a fourth year undergraduate student in the Department of. Computer Science and. Engineering, Narayana. Engineering College,. Nellore, Andhra Pradesh. He would like to work in operating systems, computer networks and also in Internet security concepts. Keywords. Operating systems, file sys-.

  13. Operational Resilience

    Science.gov (United States)

    2014-10-16

    the so-called Threat Image Pro 51 April 2014 Operational Stress on Internet and eCommerce THE WALL STREET JOURNAL. TECH TECHNOLOGY Massive OpenSSL...8217!;:;a.L~ and · ...... -n ... ,.,. ... ,. 53 September 24, 2014 Operational Stress on Internet and eCommerce ::;:\\\\ t?nQCldQt?~ . REVIEWS

  14. Operation amplifier

    NARCIS (Netherlands)

    Tetsuya, Saito; Nauta, Bram

    2008-01-01

    To provide an operation amplifier which improves power source voltage removal ratios while assuring phase compensation characteristics, and therefore can be realized with a small-scale circuit and low power consumption. SOLUTION: The operation amplifier comprises: a differential amplifier circuit 1;

  15. Operation Amplifier

    NARCIS (Netherlands)

    Tetsuya, Saito; Nauta, Bram

    2011-01-01

    PROBLEM TO BE SOLVED: To provide an operation amplifier which improves power source voltage removal ratios while assuring phase compensation characteristics, and therefore can be realized with a small-scale circuit and low power consumption. SOLUTION: The operation amplifier comprises: a

  16. Operation Amplifier

    NARCIS (Netherlands)

    Tetsuya, S.; Nauta, Bram

    2007-01-01

    PROBLEM TO BE SOLVED: To provide an operation amplifier which improves power source voltage removal ratios while assuring phase compensation characteristics, and therefore can be realized with a small-scale circuit and low power consumption. ; SOLUTION: The operation amplifier comprises: a

  17. Comparative analysis of gyrotron backward-wave oscillators operating at different cyclotron harmonics

    International Nuclear Information System (INIS)

    Yeh, Y.S.; Chang, T.H.; Wu, T.S.

    2004-01-01

    A comparative analysis between the fundamental and second cyclotron harmonics of gyrotron backward-wave oscillators (gyro-BWOs) is presented. The simulation results reveal that nonlinear field contraction is a common feature for both harmonic interactions. Besides, the electron transit angle, used to characterize the axial modes of the fundamental harmonic TE 11 mode at the start-oscillation conditions, is found to be applicable even for the second harmonic TE 21 mode. Each axial mode of either the fundamental harmonic TE 11 or the second harmonic TE 21 modes is maintained at a constant value of the electron transit angle while changing the operating parameters, such as magnetic field and beam voltage. Extensive numerical calculations are conducted for the start-oscillation currents and tuning properties. Moreover, single-mode operating regimes are suggested where the second harmonic TE 21 gyro-BWO could generate a considerable output power, comparing with the fundamental harmonic TE 11 gyro-BWO

  18. Aceleración de la enseñanza para alumnos superdotados: argumentos favorables y contrarios

    Directory of Open Access Journals (Sweden)

    Renata Rodrigues Maia-Pinto

    2012-06-01

    Full Text Available Learning acceleration for gifted students: Favorable and unfavorable argumentsThis paper analyzes acceleration in education as a practice for meeting the educational needs of gifted students, and points out favorable and unfavorable arguments on the use of this practice. Acceleration is an educational practice consisting of several teaching strategies designed to encourage academically gifted students and reduce their time spent in school. It promotes faster learning by matching the curriculum to the student’s level of knowledge, interest and motivation. There are several arguments in favor of acceleration, such as the improvement of academic performance, self-esteem and student’s social adjustment. However, educators are reluctant to implement this practice, arguing that students may be immature or lose part of the content of the regular curriculum.

  19. Seventy seven ecological and ethical arguments in favor of the nuclear energy

    International Nuclear Information System (INIS)

    Mocanu, H.; drahor@SoftHome.net.

    2003-01-01

    In the paper 55 ecological and 22 ethical arguments are presented in favour of the nuclear energy alternative. Generally, the arguments are presented in comparison with the alternative electric energy sources, evidencing the advantages of the nuclear energy, as for instance the control and confinement of the nuclear waste as compared with the free discharge in the environment of the wastes from fossil fuel plants. Advantages of operating the equivalent nuclear power plants instead of operating fossil fuel power plants in reducing the CO 2 , CO, SO 2 , NOx, dust, ashes, CH 4 , heavy metals, etc. are also stressed. Reducing the emission of CO 2 , N 2 O, etc. results in attenuation of ozone layer depletion, greenhouse effects, global warming and climate changes, which we face today. Also, by replacing the fossil fuel power plants with nuclear power plants the environmental pollution (even radioactive) will be reduced as well as the risks of marine, ground and/or underground ecological accidents (during transport of the fossil fuels), and in addition, the requirements for mineral resources necessary in constructing and operating power plants will be diminished. Ethical arguments in favour of nuclear energy are presented as follows: - the preservation of the fossil fuels by bequeathing them to the generations to come for a higher, more efficient use in chemical industry, pharmaceutical industry, etc; - the minimal degradation of the environment; - promotion of modern/advanced technologies, enhancing the general progress of human society and reducing the brain-drain from the countries/economies undergoing the development process. These arguments are extracted from a large variety of sources listed at the end of the paper. (author)

  20. Hanaro operation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ji Bok; Jeon, Byung Jin; Kwack, Byung Ho [and others

    1997-01-01

    HANARO was configurated its first operating core in 1995. Long term operation test was conducted up to 3-1 cycle during 1996, in order to investigate the reactor characteristics due to fuel depletion and additional fuel loading. Now HANARO has accumulated 168.4 days of total operation time and 2,687.5 MWD of total thermal output. Reactor analysis, producing operation datum and its validation with test, periodic inspection and maintenance of the facility are continuously conducted for safe operation of the HANARO. Conducted the verification tests for installed utilization facilities, and successfully performed the radiation emergency drill. The shutdown report of TRIGA Mark II and III was submitted to MOST, and decommissioning will be started from 1997. (author). 70 tabs., 50 figs., 27 refs.

  1. Preliminary study of favorability for uranium of the Sangre de Cristo Formation in the Las Vegas basin, northeastern New Mexico

    International Nuclear Information System (INIS)

    May, R.T.; Strand, J.R.; Reid, B.E.; Phillips, W.R.

    1977-12-01

    Uranium favorability of the Sangre de Cristo Formation (Pennsylvanian-Permian) in the Las Vegas basin has been evaluated. The Las Vegas basin project area, located in Colfax, Mora, and San Miguel Counties, New Mexico, comprises about 3,489 sq mi. The formation contains sedimentologic and stratigraphic characteristics that are considered favorable for uranium deposition. Field investigations consisted of section measuring, rock sampling, and ground radiometric reconnaissance. North-south and east-west cross sections of the basin were prepared from well logs and measured sections. Petrographic, chemical, and spectrographic analyses were conducted on selected samples. Stratigraphic and sedimentologic information were used to determine depositional environments. The most favorable potential host rocks include red to pink, coarse-grained, poorly sorted, feldspathic to arkosic lenticular sandstones with stacked sandstone thicknesses of more than 20 ft and sandstone-to-shale ratios between 1:1 and 2:1. The sandstone is interbedded with mudstone and contains carbonaceous debris and anomalous concentrations of uranium locally. Areas of maximum favorability are found in a braided-stream, alluvial-plain depositional environment in the north-central part of the Las Vegas basin. There, carbonaceous material is well preserved, probably due to rapid subsidence and burial. Furthermore, uranium favorability is highest in the lower half of the formation because carbonaceous wood and plant fragments, as well as known uranium deposits, are concentrated in this zone. Piedmont deposits in the north and east, and meander-belt, alluvial-plain deposits in the south, are not considered favorable because of the paucity of uranium deposits and a minimum of carbonaceous material

  2. Sustained favorable long-term outcome in the treatment of schizophrenia: a 3-year prospective observational study

    Directory of Open Access Journals (Sweden)

    Ascher-Svanum Haya

    2011-08-01

    Full Text Available Abstract Background This study of chronically ill patients with schizophrenia aimed to identify patients who achieve sustained favorable long-term outcome - when the outcome incorporates severity of symptoms, level of functioning, and use of acute care services - and to identify the best baseline predictors of achieving this sustained favorable long-term outcome. Methods Using data from the United States Schizophrenia Care and Assessment Program (US-SCAP (N = 2327, a large 3-year prospective, multisite, observational study of individuals treated for schizophrenia in the US, a hierarchical cluster analysis was performed to group patients based upon baseline symptom severity. Symptom severity was assessed using the Positive and Negative Syndrome Scale (PANSS scores, level of functioning, and use of acute care services. Level of functioning reflected patient-reported productivity and clinician-rated occupational role functioning. Use of acute care services reflected self-reported psychiatric hospitalization and emergency service use. Change of health state was determined over the 3-year period. A patient was classified as having a sustained favorable long-term outcome if their health state values had the closest distance to the defined "best baseline cluster" at each point over the length of the study. Stepwise logistic regression was used to determine baseline predictors of sustained favorable long-term outcome. Results At baseline, 5 distinct health state clusters were identified, ranging from "best" to "worst." Of 1635 patients with sufficient data, only 157 (10% experienced sustained favorable long-term outcome during the 2-years postbaseline. The baseline predictors associated with sustained favorable long-term outcome included better quality of life, more daily activities, patient-reported clearer thinking from medication, better global functioning, being employed, not being a victim of a crime, not having received individual therapy, and not

  3. Criteria for uranium occurrences in Saskatchewan and Australia as guides to favorability for similar deposits in the United States

    International Nuclear Information System (INIS)

    Kalliokoski, J.; Langford, F.F.; Ojakangas, R.W.

    1978-07-01

    The objective of this study was to explain the occurrence of the large uranium deposits that have been found in northern Saskatchewan and the Northern Territory of Australia, to provide criteria to evaluate the favorability of Proterozoic rocks in the United States for similar deposits. All of these deposits belong to the class known as the Proterozoic unconformity-type pitchblende deposits. Chapters are devoted to: uranium deposits in Saskatchewan; uranium deposits of the Darwin and Arnhem Land area, Northern Territory of Australia; model for the Proterozoic unconformity-type pitchblende deposits; and evaluation of the geology of selected states for its favorability for Proterozoic unconformity-type pitchblende deposits

  4. Toddlers favor communicatively presented information over statistical reliability in learning about artifacts.

    Science.gov (United States)

    Marno, Hanna; Csibra, Gergely

    2015-01-01

    Observed associations between events can be validated by statistical information of reliability or by testament of communicative sources. We tested whether toddlers learn from their own observation of efficiency, assessed by statistical information on reliability of interventions, or from communicatively presented demonstration, when these two potential types of evidence of validity of interventions on a novel artifact are contrasted with each other. Eighteen-month-old infants observed two adults, one operating the artifact by a method that was more efficient (2/3 probability of success) than that of the other (1/3 probability of success). Compared to the Baseline condition, in which communicative signals were not employed, infants tended to choose the less reliable method to operate the artifact when this method was demonstrated in a communicative manner in the Experimental condition. This finding demonstrates that, in certain circumstances, communicative sanctioning of reliability may override statistical evidence for young learners. Such a bias can serve fast and efficient transmission of knowledge between generations.

  5. Operator lattices

    International Nuclear Information System (INIS)

    Bender, C.M.

    1984-01-01

    The finite-element method enables us to convert the operator differential equations of a quantum field theory into operator difference equations. These difference equations are consistent with the requirements of quantum mechanics and they do not exhibit fermion doubling, a problem that frequently plagues lattice treatments of fermions. Guage invariance can also be incorporated into the difference equations. On a finite lattice the operator difference equations can be solved in closed form. For the case of the Schwinger model the anomaly is computed and results in excellent agreement are obtained with the known continuum value

  6. Reactor operation

    CERN Document Server

    Shaw, J

    2013-01-01

    Reactor Operation covers the theoretical aspects and design information of nuclear reactors. This book is composed of nine chapters that also consider their control, calibration, and experimentation.The opening chapters present the general problems of reactor operation and the principles of reactor control and operation. The succeeding chapters deal with the instrumentation, start-up, pre-commissioning, and physical experiments of nuclear reactors. The remaining chapters are devoted to the control rod calibrations and temperature coefficient measurements in the reactor. These chapters also exp

  7. Operational Research

    CERN Document Server

    Almeida, João; Oliveira, José; Pinto, Alberto

    2018-01-01

    This proceedings book presents selected contributions from the XVIII Congress of APDIO (the Portuguese Association of Operational Research) held in Valença on June 28–30, 2017. Prepared by leading Portuguese and international researchers in the field of operations research, it covers a wide range of complex real-world applications of operations research methods using recent theoretical techniques, in order to narrow the gap between academic research and practical applications. Of particular interest are the applications of, nonlinear and mixed-integer programming, data envelopment analysis, clustering techniques, hybrid heuristics, supply chain management, and lot sizing and job scheduling problems. In most chapters, the problems, methods and methodologies described are complemented by supporting figures, tables and algorithms.   The XVIII Congress of APDIO marked the 18th installment of the regular biannual meetings of APDIO – the Portuguese Association of Operational Research. The meetings bring toget...

  8. Operator training

    International Nuclear Information System (INIS)

    Wirstad, J.

    1983-12-01

    The traditional operator job is changing, which among other things has generated a need for better job training. Surprisingly increased process automation has lead to increased operator qualifications, i.e. basic job training but also up-date and rehearsal training within certain fixed intervals. There are several, similar models for instructional system development available in the literature. One model which is of special interest integrates Operator Training development and Man-Machine Interfaces development. The extent to which Systematic Operator Training has been implemented varies with branches and companies. The nuclear power branch is given as an example in the report. This branch probably represents something better than the average among the process industries.(author)

  9. Peace Operations

    National Research Council Canada - National Science Library

    Proks, Josef

    2000-01-01

    Peace operations are more and more important in the contemporary world. The end of the Cold War increased not only possibilities of solving disputes by the international community but also by the number and diversity of threats and issues...

  10. Operator theory

    CERN Document Server

    2015-01-01

    A one-sentence definition of operator theory could be: The study of (linear) continuous operations between topological vector spaces, these being in general (but not exclusively) Fréchet, Banach, or Hilbert spaces (or their duals). Operator theory is thus a very wide field, with numerous facets, both applied and theoretical. There are deep connections with complex analysis, functional analysis, mathematical physics, and electrical engineering, to name a few. Fascinating new applications and directions regularly appear, such as operator spaces, free probability, and applications to Clifford analysis. In our choice of the sections, we tried to reflect this diversity. This is a dynamic ongoing project, and more sections are planned, to complete the picture. We hope you enjoy the reading, and profit from this endeavor.

  11. The Bias in Favor of Venture Capital Finance in U.S. Entrepreneurial Education: At the Expense of Trade Credit

    Science.gov (United States)

    Clement, Thomas; LeMire, Steven; Silvernagel, Craig

    2015-01-01

    The authors examine whether U.S. college-level entrepreneurship education demonstrates a bias favoring venture capital (VC) financing while marginalizing trade credit financing, and the resulting impact on entrepreneurship students. A sample of U.S. business textbooks and survey data from entrepreneurship students reveals a significant bias toward…

  12. Radiation therapy for chest wall recurrence of breast cancer after mastectomy in a favorable subgroup of patients

    International Nuclear Information System (INIS)

    Hsi, R. Alex; Antell, Andrew; Schultz, Delray J.; Solin, Lawrence J.

    1998-01-01

    Purpose: Long-term outcome after radiation therapy for local-regional recurrence of breast cancer after mastectomy is generally poor. This study was performed to evaluate the long-term outcome for a potentially favorable subgroup of patients with chest wall recurrence. Methods and Materials: Of 71 patients with an isolated local-regional recurrence of breast cancer after mastectomy, 18 were identified who met the following favorable selection criteria: 1) a disease-free interval after mastectomy of 2 years or more, 2) an isolated chest wall recurrence, and 3) tumor size < 3 cm or complete excision of the recurrent disease. All 18 patients were treated with local-regional irradiation between 1967 and 1988. Radiotherapy (RT) was delivered to the chest wall to a median total dose of 60 Gy (range 30-66 Gy). Four patients received adjuvant chemotherapy and six patients received adjuvant hormonal therapy. Results: With a median follow-up of 8.4 years, nine of 18 patients were alive and free of disease. The 10-year actuarial overall and cause-specific survivals were 72% and 77%, respectively. The 10-year actuarial relapse-free survival and local control were 42% and 86%, respectively. Conclusion: Treatment for a local-regional recurrence of breast cancer after mastectomy in a favorable subgroup of patients results in a high rate of long-term survival as well as excellent local control. Aggressive treatment is warranted in this favorable subgroup of patients. 1998 Elsevier Science Inc

  13. Explaining financial and prosocial biases in favor of attractive people: Interdisciplinary perspectives from economics, social psychology, and evolutionary psychology.

    Science.gov (United States)

    Maestripieri, Dario; Henry, Andrea; Nickels, Nora

    2017-01-01

    Financial and prosocial biases in favor of attractive adults have been documented in the labor market, in social transactions in everyday life, and in studies involving experimental economic games. According to the taste-based discrimination model developed by economists, attractiveness-related financial and prosocial biases are the result of preferences or prejudices similar to those displayed toward members of a particular sex, racial, ethnic, or religious group. Other explanations proposed by economists and social psychologists maintain that attractiveness is a marker of personality, intelligence, trustworthiness, professional competence, or productivity. Evolutionary psychologists have argued that attractive adults are favored because they are preferred sexual partners. Evidence that stereotypes about attractive people are causally related to financial or prosocial biases toward them is weak or nonexistent. Consistent with evolutionary explanations, biases in favor of attractive women appear to be more consistent or stronger than those in favor of attractive men, and biases are more consistently reported in interactions between opposite-sex than same-sex individuals. Evolutionary explanations also account for increased prosocial behavior in situations in which attractive individuals are simply bystanders. Finally, evolutionary explanations are consistent with the psychological, physiological, and behavioral changes that occur when individuals are exposed to potential mates, which facilitate the expression of courtship behavior and increase the probability of occurrence of mating. Therefore, multiple lines of evidence suggest that mating motives play a more important role in driving financial and prosocial biases toward attractive adults than previously recognized.

  14. Laparoscopic colectomy compares favorably with colectomy by laparotomy for reduction of postoperative ileus.

    Science.gov (United States)

    Chen, H H; Wexner, S D; Iroatulam, A J; Pikarsky, A J; Alabaz, O; Nogueras, J J; Nessim, A; Weiss, E G

    2000-01-01

    The aim of this study was to compare the length of postoperative ileus in patients undergoing colectomy by either laparotomy or laparoscopy. A total of 166 patients were studied. These patients were divided into two groups: Group 1, in which colectomy was done laparoscopically, and Group 2, consisting of patients undergoing laparotomy. Both groups contained 83 patients who were matched for disease severity, indications for surgery, and procedure. Indications for surgery included sigmoid diverticulitis in 12 (14 percent) patients, polyps in 22 (27 percent), Crohn's disease in 21 (25 percent), colorectal cancer in 11 (13 percent), stoma reversal in 8 (10 percent), rectal prolapse in 3 (4 percent), and other indications in 6 (7 percent) in each group. Operations were colectomy with anastomosis (42 ileocolic, 26 colorectal, 6 colocolic, 4 ileorectal, and 2 ileal J pouch) or without anastomosis (3 abdominoperineal resections) performed by the same surgeons during the same time period January 1993 to October 1996). The nasogastric tube was removed from all patients immediately after surgery in both groups. All patients received a clear liquid diet on the first postoperative day, followed by a regular diet as tolerated. The nasogastric tube was reinserted if two or more episodes of emesis of more than 200 ml occurred in the absence of bowel movement. Patients were discharged from the hospital when tolerating a regular diet without evidence of ileus. Statistical analysis was performed using unpaired t-test and Fisher's exact probability test. The male-to-female ratio was 38 to 45 in both groups. A total of 10 (12 percent) and 23 (28 percent) patients in Group 1 and Group 2 had emesis (P = 0.02), and the rate of nasogastric tube reinsertion was 5 (6 percent) and 13 (16 percent), respectively (P > 0.05). There were significant differences between Groups 1 and 2 relative to the lengths of ileus (3.5 +/- 1.3 vs. 5.4 +/- 1.7 days, respectively; P < 0.001), hospitalization (6

  15. Registration of indoor TLS data: in favor of a probabilistic approach initialized by geo-location

    International Nuclear Information System (INIS)

    Hullo, Jean-Francois

    2013-01-01

    Many pre-maintenance operations of industrial facilities currently resort on to three dimensional CAD models. The acquisition of these models is performed from point clouds measured by Terrestrial Laser Scanning (TLS). When the scenes are complex, several view points for scanning, also known as stations, are necessary to ensure the completeness and the density of the survey data. The generation of a global point cloud, i.e. the expression of all the acquired data in a common reference frame, is a crucial step called registration. During this process, the pose parameters are estimated. If the GNSS Systems are now a solution for many outdoor scenes, the registration of indoor TLS data still remains a challenge. The goal of this thesis is to improve the acquisition process of TLS data in industrial environments. The aim is to guarantee the precision and accuracy of acquired data, while optimizing on-site acquisition time and protocols by, as often as possible, freeing the operator from the constraints inherent to conventional topography surveys. In a first part, we consider the state of the art of the means and methods used during the acquisition of dense point clouds of complex interior scenes (Part I). In a second part, we study and evaluate the data available for the registration: terrestrial laser data, primitive reconstruction algorithms in point clouds and indoor geo-location Systems (Part II). In the third part, we then formalize and experiment a registration algorithm based on the use of matched primitives, reconstructed from per station point clouds ( Part III). We finally propose a probabilistic approach for matching primitives, allowing the integration of a priori information and uncertainty in the constraints System used for calculating poses (Part IV). The contributions of our work are as follows: - to take a critical look at current methods of TLS data acquisition in industrial environments, - to evaluate, through experimentations, the information

  16. Pre- and postcopulatory sexual selection favor aggressive, young males in polyandrous groups of red junglefowl.

    Science.gov (United States)

    McDonald, Grant C; Spurgin, Lewis G; Fairfield, Eleanor A; Richardson, David S; Pizzari, Tommaso

    2017-06-01

    A challenge in evolutionary biology is to understand the operation of sexual selection on males in polyandrous groups, where sexual selection occurs before and after mating. Here, we combine fine-grained behavioral information (>41,000 interactions) with molecular parentage data to study sexual selection in replicated, age-structured groups of polyandrous red junglefowl, Gallus gallus. Male reproductive success was determined by the number of females mated (precopulatory sexual selection) and his paternity share, which was driven by the polyandry of his female partners (postcopulatory sexual selection). Pre- and postcopulatory components of male reproductive success covaried positively; males with high mating success also had high paternity share. Two male phenotypes affected male pre- and postcopulatory performance: average aggressiveness toward rival males and age. Aggressive males mated with more females and more often with individual females, resulting in higher sexual exclusivity. Similarly, younger males mated with more females and more often with individual females, suffering less intense sperm competition than older males. Older males had a lower paternity share even allowing for their limited sexual exclusivity, indicating they may produce less competitive ejaculates. These results show that-in these populations-postcopulatory sexual selection reinforces precopulatory sexual selection, consistently promoting younger and more aggressive males. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

  17. Rich pickings near large communal roosts favor 'gang' foraging by juvenile common ravens, Corvus corax.

    Directory of Open Access Journals (Sweden)

    Sasha R X Dall

    Full Text Available Ravens (Corvus corax feed primarily on rich but ephemeral carcasses of large animals, which are usually defended by territorial pairs of adults. Non-breeding juveniles forage socially and aggregate in communal winter roosts, and these appear to function as 'information centers' regarding the location of the rare food bonanzas: individuals search independently of one another and pool their effort by recruiting each other at roosts. However, at a large raven roost in Newborough on Anglesey, North Wales, some juveniles have been observed recently to forage in 'gangs' and to roost separately from other birds. Here we adapt a general model of juvenile common raven foraging behavior where, in addition to the typical co-operative foraging strategy, such gang foraging behavior could be evolutionarily stable near winter raven roosts. We refocus the model on the conditions under which this newly documented, yet theoretically anticipated, gang-based foraging has been observed. In the process, we show formally how the trade off between search efficiency and social opportunity can account for the existence of the alternative social foraging tactics that have been observed in this species. This work serves to highlight a number of fruitful avenues for future research, both from a theoretical and empirical perspective.

  18. Applied Operations Research: Operator's Assistant

    Science.gov (United States)

    Cole, Stuart K.

    2015-01-01

    NASA operates high value critical equipment (HVCE) that requires trouble shooting, periodic maintenance and continued monitoring by Operations staff. The complexity HVCE and information required to maintain and trouble shoot HVCE to assure continued mission success as paper is voluminous. Training on new HVCE is commensurate with the need for equipment maintenance. LaRC Research Directorate has undertaken a proactive research to support Operations staff by initiation of the development and prototyping an electronic computer based portable maintenance aid (Operator's Assistant). This research established a goal with multiple objectives and a working prototype was developed. The research identified affordable solutions; constraints; demonstrated use of commercial off the shelf software; use of the US Coast Guard maintenance solution; NASA Procedure Representation Language; and the identification of computer system strategies; where these demonstrations and capabilities support the Operator, and maintenance. The results revealed validation against measures of effectiveness and overall proved a substantial training and capability sustainment tool. The research indicated that the OA could be deployed operationally at the LaRC Compressor Station with an expectation of satisfactorily results and to obtain additional lessons learned prior to deployment at other LaRC Research Directorate Facilities. The research revealed projected cost and time savings.

  19. Operating experience

    International Nuclear Information System (INIS)

    McRae, L.P.; Six, D.E.

    1991-01-01

    In 1987, Westinghouse Hanford Company began operating a first-generation integrated safeguards system in the Plutonium Finishing Plant storage vaults. This Vault Safety and Inventory System is designed to integrate data into a computer-based nuclear material inventory monitoring system. The system gathers, in real time, measured physical parameters that generate nuclear material inventory status data for thousands of stored items and sends tailored report to the appropriate users. These data include canister temperature an bulge data reported to Plant Operations and Material Control and Accountability personnel, item presence and identification data reported to Material Control and Accountability personnel, and unauthorized item movement data reported to Security response forces and Material Control and Accountability personnel. The Westinghouse Hanford Company's experience and operational benefits in using this system for reduce radiation exposure, increase protection against insider threat, and real-time inventory control are discussed in this paper

  20. Operator companion

    International Nuclear Information System (INIS)

    Natalizio, A.; Anderson, J.W.D.; Sills, H.E.

    1988-01-01

    Abundant, cheap computing power has provided industry with a far greater opportunity than was available one or two decades ago to automate industrial processes and to improve the man-machine interface. Exciting innovations in knowledge representation methods arising from artificial intelligence research pave the way for advanced support systems for assisting plant operators. AECL has recognized the importance of knowledge based system technology, particularly expert systems, in the achievement of this objective and also, as a strategic technology to be fully exploited in the next generation of CANDU reactors. Operator Companion, an expert system intended to diagnose plant faults and advise the operator on appropriate restoring or corrective actions, is a major undertaking which is receiving support within the research and engineering groups of AECL

  1. Failure of delayed and prolonged hypothermia to favorably affect hemorrhagic stroke in rats.

    Science.gov (United States)

    MacLellan, Crystal; Shuaib, Ashfaq; Colbourne, Frederick

    2002-12-20

    Prolonged hypothermia reduces global and focal cerebral ischemic injury in rodents even when delayed for hours. However, it is not known whether hypothermia can reduce injury following intracerebral hemorrhage (ICH). Accordingly, we studied striatal injury and concomitant motor deficits after 2 days of hypothermia, induced 1 h after creation of an ICH by infusion of bacterial collagenase. Rats were first trained to retrieve food pellets in the Montoya staircase task. They were then implanted with core temperature telemetry probes and later subjected to normothermic ICH or sham operation (vehicle injection). Half self-regulated temperature after surgery; others were cooled to 33 degrees C (24 h) and then 35 degrees C (24 h). Hypothermia did not affect behavioral scores of sham animals (89.8% of baseline in staircase test) or histology. Untreated (normothermic) ICH rats lost 23.1 mm(3) of tissue at a 1-month survival, which significantly impaired food pellet retrieval (66.0% retrieval) with the contralateral limb (tested on days 21-25). Contrary to our hypothesis, hypothermia failed to lessen either the reaching impairment (62.8%) or the lesion (22.2 mm(3)). While other hemorrhagic insults or complications may be improved with hypothermia, our data suggest that it will not salvage tissue that is quickly lost after ICH. We also assessed walking across a horizontal ladder and spontaneous paw usage in a cylinder test at 1-4 weeks after ICH, but neither test was sufficiently sensitive to this mild insult. This indicates that skilled reaching is more severely disrupted than spontaneous paw usage or walking after a striatal hemorrhage.

  2. Posterolateral Trajectories Favor a Longer Motor Domain in Subthalamic Nucleus Deep Brain Stimulation for Parkinson Disease.

    Science.gov (United States)

    Tamir, Idit; Marmor-Levin, Odeya; Eitan, Renana; Bergman, Hagai; Israel, Zvi

    2017-10-01

    The clinical outcome of patients with Parkinson disease (PD) who undergo subthalamic nucleus (STN) deep brain stimulation (DBS) is, in part, determined by the length of the electrode trajectory through the motor STN domain, the dorsolateral oscillatory region (DLOR). Trajectory length has been found to correlate with the stimulation-related improvement in patients' motor function (estimated by part III of the United Parkinson's Disease Rating Scale [UPDRS]). Therefore, it seems that ideally trajectories should have maximal DLOR length. We retrospectively studied the influence of various anatomic aspects of the brains of patients with PD and the geometry of trajectories planned on the length of the DLOR and STN recorded during DBS surgery. We examined 212 trajectories and 424 microelectrode recording tracks in 115 patients operated on in our center between 2010 and 2015. We found a strong correlation between the length of the recorded DLOR and STN. Trajectories that were more lateral and/or posterior in orientation had a longer STN and DLOR pass, although the DLOR/STN fraction length remained constant. The STN target was more lateral when the third ventricle was wider, and the latter correlated with older age and male gender. Trajectory angles correlate with the recorded STN and DLOR lengths, and should be altered toward a more posterolateral angle in older patients and atrophied brains to compensate for the changes in STN location and geometry. These fine adjustments should yield a longer motor domain pass, thereby improving the patient's predicted outcome. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Sex Differences and Bone Metastases of Breast, Lung, and Prostate Cancers: Do Bone Homing Cancers Favor Feminized Bone Marrow?

    Directory of Open Access Journals (Sweden)

    Mary C. Farach-Carson

    2017-08-01

    Full Text Available Sex-associated differences in bone metastasis formation from breast, lung, and prostate cancer exist in clinical studies, but have not been systematically reviewed. Differences in the bone marrow niche can be attributed to sexual dimorphism, to genetic variations that affect sex hormone levels, or to the direct effects of sex hormones, natural or exogenously delivered. This review describes the present understanding of sex-associated and sex hormone level differences in the marrow niche and in formation of bone metastasis during the transition of these three cancers from treatable disease to an often untreatable, lethal metastatic one. Our purpose is to provide insight into some underlying molecular mechanisms for hormonal influence in bone metastasis formation, and to the potential influence of sexual dimorphism, genetic differences affecting sex assignment, and sex hormone level differences on the bone niche and its favorability for metastasis formation. We reviewed publications in PubMed and EMBASE, including full length manuscripts, case reports, and clinical studies of relevance to our topic. We focused on bone metastasis formation in breast, lung, and prostate cancer because all three commonly present with bone metastases. Several clear observations emerged. For breast cancer bone metastasis formation, estrogen receptor (ER signaling pathways indicate a role for ER beta (ERβ. Estrogen influences the bone microenvironment, creating and conditioning a favorable niche for colonization and breast cancer progression. For lung cancer, studies support the hypothesis that females have a more favorable bone microenvironment for metastasis formation. For prostate cancer, a decrease in the relative androgen to estrogen balance or a “feminization” of bone marrow favors bone metastasis formation, with a potentially important role for ERβ that may be similar to that in breast cancer. Long-term estrogen administration or androgen blockade in males

  4. Definition and Validation of "Favorable High-Risk Prostate Cancer": Implications for Personalizing Treatment of Radiation-Managed Patients.

    Science.gov (United States)

    Muralidhar, Vinayak; Chen, Ming-Hui; Reznor, Gally; Moran, Brian J; Braccioforte, Michelle H; Beard, Clair J; Feng, Felix Y; Hoffman, Karen E; Choueiri, Toni K; Martin, Neil E; Sweeney, Christopher J; Trinh, Quoc-Dien; Nguyen, Paul L

    2015-11-15

    To define and validate a classification of favorable high-risk prostate cancer that could be used to personalize therapy, given that consensus guidelines recommend similar treatments for all radiation-managed patients with high-risk disease. We studied 3618 patients with cT1-T3aN0M0 high-risk or unfavorable intermediate-risk prostate adenocarcinoma treated with radiation at a single institution between 1997 and 2013. Favorable high-risk was defined as T1c disease with either Gleason 4 + 4 = 8 and prostate-specific antigen 20 ng/mL. Competing risks regression was used to determine differences in the risk of prostate cancer-specific mortality (PCSM) after controlling for baseline factors and treatment. Our results were validated in a cohort of 13,275 patients using the Surveillance, Epidemiology, and End Results (SEER)-Medicare linked database. Patients with favorable high-risk disease had significantly better PCSM than other men with high-risk disease (adjusted hazard ratio [AHR] 0.42, 95% confidence interval [CI] 0.18-0.996, P=.049) and similar PCSM as men with unfavorable intermediate-risk disease (AHR 1.17, 95% CI 0.50-2.75, P=.710). We observed very similar results within the SEER-Medicare cohort (favorable high-risk vs other high-risk: AHR 0.21, 95% CI 0.11-0.41, Prisk vs unfavorable intermediate-risk: AHR 0.67, 95% CI 0.33-1.36, P=.268). Patients with favorable high-risk prostate cancer have significantly better PCSM than other patients with high-risk disease and similar PCSM as those with unfavorable intermediate-risk disease, who are typically treated with shorter-course androgen deprivation therapy. This new classification system may allow for personalization of treatment within high-risk disease, such as consideration of shorter-course androgen deprivation therapy for favorable high-risk disease. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  5. Sex Differences and Bone Metastases of Breast, Lung, and Prostate Cancers: Do Bone Homing Cancers Favor Feminized Bone Marrow?

    Science.gov (United States)

    Farach-Carson, Mary C; Lin, Sue-Hwa; Nalty, Theresa; Satcher, Robert L

    2017-01-01

    Sex-associated differences in bone metastasis formation from breast, lung, and prostate cancer exist in clinical studies, but have not been systematically reviewed. Differences in the bone marrow niche can be attributed to sexual dimorphism, to genetic variations that affect sex hormone levels, or to the direct effects of sex hormones, natural or exogenously delivered. This review describes the present understanding of sex-associated and sex hormone level differences in the marrow niche and in formation of bone metastasis during the transition of these three cancers from treatable disease to an often untreatable, lethal metastatic one. Our purpose is to provide insight into some underlying molecular mechanisms for hormonal influence in bone metastasis formation, and to the potential influence of sexual dimorphism, genetic differences affecting sex assignment, and sex hormone level differences on the bone niche and its favorability for metastasis formation. We reviewed publications in PubMed and EMBASE, including full length manuscripts, case reports, and clinical studies of relevance to our topic. We focused on bone metastasis formation in breast, lung, and prostate cancer because all three commonly present with bone metastases. Several clear observations emerged. For breast cancer bone metastasis formation, estrogen receptor (ER) signaling pathways indicate a role for ER beta (ERβ). Estrogen influences the bone microenvironment, creating and conditioning a favorable niche for colonization and breast cancer progression. For lung cancer, studies support the hypothesis that females have a more favorable bone microenvironment for metastasis formation. For prostate cancer, a decrease in the relative androgen to estrogen balance or a "feminization" of bone marrow favors bone metastasis formation, with a potentially important role for ERβ that may be similar to that in breast cancer. Long-term estrogen administration or androgen blockade in males may feminize the bone

  6. To repair or not to repair: with FAVOR there is no question

    Science.gov (United States)

    Garetto, Anthony; Schulz, Kristian; Tabbone, Gilles; Himmelhaus, Michael; Scheruebl, Thomas

    2016-10-01

    In the mask shop the challenges associated with today's advanced technology nodes, both technical and economic, are becoming increasingly difficult. The constant drive to continue shrinking features means more masks per device, smaller manufacturing tolerances and more complexity along the manufacturing line with respect to the number of manufacturing steps required. Furthermore, the extremely competitive nature of the industry makes it critical for mask shops to optimize asset utilization and processes in order to maximize their competitive advantage and, in the end, profitability. Full maximization of profitability in such a complex and technologically sophisticated environment simply cannot be achieved without the use of smart automation. Smart automation allows productivity to be maximized through better asset utilization and process optimization. Reliability is improved through the minimization of manual interactions leading to fewer human error contributions and a more efficient manufacturing line. In addition to these improvements in productivity and reliability, extra value can be added through the collection and cross-verification of data from multiple sources which provides more information about our products and processes. When it comes to handling mask defects, for instance, the process consists largely of time consuming manual interactions that are error prone and often require quick decisions from operators and engineers who are under pressure. The handling of defects itself is a multiple step process consisting of several iterations of inspection, disposition, repair, review and cleaning steps. Smaller manufacturing tolerances and features with higher complexity contribute to a higher number of defects which must be handled as well as a higher level of complexity. In this paper the recent efforts undertaken by ZEISS to provide solutions which address these challenges, particularly those associated with defectivity, will be presented. From automation

  7. Operational indicators

    International Nuclear Information System (INIS)

    2010-01-01

    The chapter presents the operational indicators related to budget, travel costs and tickets, the evolution of the annual program for regulatory inspection, the scientific production, requested patents and the numbers related to the production of the services offered by the Institution

  8. Operating Systems

    Indian Academy of Sciences (India)

    areas in which this type is useful are multimedia, virtual reality, and advanced scientific projects such as undersea exploration and planetary rovers. Because of the expanded uses for soft real-time functionality, it is finding its way into most current operating systems, including major versions of Unix and Windows NT OS.

  9. Peace Operations

    National Research Council Canada - National Science Library

    Lewis, William

    1995-01-01

    .... Indeed, despite the energetic leadership of Under Secretary-General Kofi R. Annan who directs the Department of Peacekeeping Operations, the organization has increasing difficulty in acquiring properly trained and equipped forces in time to intervene in conflict situations and humanitarian crises.

  10. Accelerator operations

    International Nuclear Information System (INIS)

    Anon.

    1980-01-01

    This section is concerned with the operation of both the tandem-linac system and the Dynamitron, two accelerators that are used for entirely different research. Developmental activities associated with the tandem and the Dynamitron are also treated here, but developmental activities associated with the superconducting linac are covered separately because this work is a program of technology development in its own right

  11. Operation Context

    DEFF Research Database (Denmark)

    Stüben, Henning; Tietjen, Anne

    2006-01-01

    Abstract: This paper seeks to challenge the notion of context from an operational perspective. Can we grasp the forces that shape the complex conditions for an architectural or urban design within the notion of context? By shifting the gaze towards the agency of architecture, contextual analysis...

  12. Operating Systems

    Indian Academy of Sciences (India)

    The process concept and concurrency are at the heart of modern operating systems (OS). A process is the unit of work in a computer system. A process must be in main memory during execution. To improve the utilization of central processing unit. (CPU) as well as the speed of its response to its users, the computer must ...

  13. Operational Circulars

    CERN Multimedia

    2003-01-01

    Operational Circular N° 4 - April 2003 Conditions for use by members of the CERN personnel of vehicles belonging to or rented by CERN - This circular has been drawn up. Operational Circular N° 5 - October 2000 Use of CERN computing facilities - Further details on the personal use of CERN computing facilities Operational Circular N° 5 and its Subsidiary Rules http://cern.ch/ComputingRules defines the rules for the use of CERN computing facilities. One of the basic principles governing such use is that it must come within the professional duties of the user concerned, as defined by the user's divisional hierarchy. However, personal use of the computing facilities is tolerated or allowed provided : a) It is in compliance with Operational Circular N° 5 and not detrimental to official duties, including those of other users; b) the frequency and duration is limited and there is a negligible use of CERN resources; c) it does not constitute a political, commercial and/or profit-making activity; d) it is not...

  14. Collective Nostalgia Is Associated With Stronger Outgroup-Directed Anger and Participation in Ingroup-Favoring Collective Action

    Directory of Open Access Journals (Sweden)

    Wing-Yee Cheung

    2017-08-01

    Full Text Available Collective nostalgia refers to longing for the way society used to be. We tested whether collective nostalgia is associated with ingroup-favoring collective action and whether this association is mediated by outgroup-directed anger and outgroup-directed contempt. We conducted an online study of Hong Kong residents (N = 111 during a large-scale democratic social movement, the Umbrella Movement, that took place in Hong Kong in 2014 in response to proposed electoral reforms by the Chinese government in Mainland China. Reported collective nostalgia for Hong Kong’s past was high in our sample and collective nostalgia predicted stronger involvement in ingroup-favoring collective action, and it did so indirectly via higher intensity of outgroup-directed anger (but not through outgroup-directed contempt. We argue that collective nostalgia has implications for strengthening ingroup-serving collective action, and we highlight the importance of arousal of group-based emotions in this process.

  15. Policies in favor of the bicycle development.; Politiques en faveur du developpement du velo. Bonnes pratiques de villes europeennes

    Energy Technology Data Exchange (ETDEWEB)

    Vallar, J.P.; Kerveillan, A.

    2001-07-01

    This study presents, ten cases of european towns which realized a policy in favor of the bicycle development. With the incitation to the displacement on foot and the public transportation, it is a good and efficient way of environmental quality. For each case, the following points are presented: global policy of the local government, technical aspects and organization, economic, environmental aspects and behavior, future orientations and contacts. (A.L.B.)

  16. Didactic interdisciplinary tasks, in order to favor the permanent formation of the teacher of the Natural Sciences in Adult Education

    OpenAIRE

    Elieser Briso-González; Alberto Díaz-Díaz

    2017-01-01

    The article exposes a system of didactic interdisciplinary tasks, that when discussing the way of how establishing didactic links between the biological, geographic and chemicals contents, through the dynamics of the methodological work; It is tried to favor the permanent formation of the teachers of the subjects of study in the area of Natural Sciences in Adult Education, and to get close to the students to an adequate understanding of the complex phenomena of his surroundings. The discreet ...

  17. "The rules of the game": how to favor entrepreneurship and creativity in a non-capitalistic economy

    OpenAIRE

    Labégorre, Quentin

    2016-01-01

    The economy, nowadays, is leading us toward a huge crisis. An environmental crisis, a new financial crisis and finally a war crisis. The aim of this paper is to propose a way to change our economy to favor a better perspective of the future. In order to promote this new economy, two suggestions are proposed: promote entrepreneurship and promote creativity within an economy that would aim at getting full employment and at avoiding any unethical action towards the environment. Se...

  18. Predicting favorable conditions for early leaf spot of peanut using output from the Weather Research and Forecasting (WRF) model.

    Science.gov (United States)

    Olatinwo, Rabiu O; Prabha, Thara V; Paz, Joel O; Hoogenboom, Gerrit

    2012-03-01

    Early leaf spot of peanut (Arachis hypogaea L.), a disease caused by Cercospora arachidicola S. Hori, is responsible for an annual crop loss of several million dollars in the southeastern United States alone. The development of early leaf spot on peanut and subsequent spread of the spores of C. arachidicola relies on favorable weather conditions. Accurate spatio-temporal weather information is crucial for monitoring the progression of favorable conditions and determining the potential threat of the disease. Therefore, the development of a prediction model for mitigating the risk of early leaf spot in peanut production is important. The specific objective of this study was to demonstrate the application of the high-resolution Weather Research and Forecasting (WRF) model for management of early leaf spot in peanut. We coupled high-resolution weather output of the WRF, i.e. relative humidity and temperature, with the Oklahoma peanut leaf spot advisory model in predicting favorable conditions for early leaf spot infection over Georgia in 2007. Results showed a more favorable infection condition in the southeastern coastline of Georgia where the infection threshold were met sooner compared to the southwestern and central part of Georgia where the disease risk was lower. A newly introduced infection threat index indicates that the leaf spot threat threshold was met sooner at Alma, GA, compared to Tifton and Cordele, GA. The short-term prediction of weather parameters and their use in the management of peanut diseases is a viable and promising technique, which could help growers make accurate management decisions, and lower disease impact through optimum timing of fungicide applications.

  19. The experience of forming a favorable image of the territory through marketing: a review of foreign press

    OpenAIRE

    Bacherikova Mariya L.

    2017-01-01

    A favorable image of the territory is a factor of attracting investors, tourists and labor force. Using of image approach to foreign territory management practice is already producing positive effects, but there are some difficulties in Russia, particularly in the Far East. Authors explore scientific publications in a foreign press, describing various marketing techniques used to territorial image forming in foreign countries. The territorial image is its image from the point of view of diff...

  20. Your Lung Operation: After Your Operation

    Medline Plus

    Full Text Available ... Surgeons Education Patients and Family Skills Programs Your Lung Operation Your Lung Operation DVD After Your Operation Back to Your Lung Operation Your Lung Operation DVD Welcome Your Lung ...

  1. Preliminary report of the uranium favorability of shear zones in the crystalline rocks of the southern Appalachians

    International Nuclear Information System (INIS)

    Penley, H.M.; Schot, E.H.; Sewell, J.M.

    1978-11-01

    Three sheared areas in the crystalline Piedmont and Blue Ridge provinces, from which uranium occurrences or anomalous radioactivity have been reported, were studied to determine their favorability for uranium mineralization. The study, which involved a literature review, geologic reconnaissance, ground radiometric surveys, and sampling of rock outcrops for petrographic and chemical analyses, indicates that more-detailed investigations of these and similar areas are warranted. In each area, surface leaching and deep residual cover make it difficult to assess the potential for uranium mineralization on the basis of results from chemical analyses for U 3 O 8 and the radiometric surveys. Although anomalous radioactivity and anomalous chemical uranium values were noted in only a few rock exposures and samples from the shear zones, the potential for uranium mineralization at depth could be much greater than indicated by these surface data. The study indicates that shear zones within Precambiran granitic basement complexes (such as the Wilson Creek Gneiss of western North Carolina, the Cranberry Gneiss of eastern Tennessee, and the Toxaway Gneiss of western South Carolina) are favorable as hosts for uranium and may contain subsurface deposits. Mylonitized graphitic schists immediately north of the Towaliga fault in Alabama and Georgia may be favorable host rocks for uranium

  2. Increases in cerebrospinal fluid caffeine concentration are associated with favorable outcome after severe traumatic brain injury in humans

    Science.gov (United States)

    Sachse, Kathleen T; Jackson, Edwin K; Wisniewski, Stephen R; Gillespie, Delbert G; Puccio, Ava M; Clark, Robert SB; Dixon, C Edward; Kochanek, Patrick M

    2013-01-01

    Caffeine, the most widely consumed psychoactive drug and a weak adenosine receptor antagonist, can be neuroprotective or neurotoxic depending on the experimental model or neurologic disorder. However, its contribution to pathophysiology and outcome in traumatic brain injury (TBI) in humans is undefined. We assessed serial cerebrospinal fluid (CSF) concentrations of caffeine and its metabolites (theobromine, paraxanthine, and theophylline) by high-pressure liquid chromatography/ultraviolet in 97 ventricular CSF samples from an established bank, from 30 adults with severe TBI. We prospectively selected a threshold caffeine level of ≥1 μmol/L (194 ng/mL) as clinically significant. Demographics, Glasgow Coma Scale (GCS) score, admission blood alcohol level, and 6-month dichotomized Glasgow Outcome Scale (GOS) score were assessed. Mean time from injury to initial CSF sampling was 10.77±3.13 h. On initial sampling, caffeine was detected in 24 of 30 patients, and the threshold was achieved in 9 patients. Favorable GOS was seen more often in patients with CSF caffeine concentration ≥ versus theobromine and paraxanthine were also associated with favorable outcome (P = 0.018 and 0.056, respectively). Caffeine and its metabolites are commonly detected in CSF in patients with severe TBI and in an exploratory assessment are associated with favorable outcome. We speculate that caffeine may be neuroprotective by long-term upregulation of adenosine A1 receptors or acute inhibition of A2a receptors. PMID:17684518

  3. Uranium favorability of tertiary sedimentary rocks of the western Okanogan highlands and of the upper Columbia River valley, Washington

    International Nuclear Information System (INIS)

    Marjaniemi, D.K.; Robins, J.W.

    1975-08-01

    Tertiary sedimentary rocks in the northern portions of the western Okanogan highlands and in the upper Columbia River valley were investigated during a regional study to determine the favorability for potential uranium resources of the Tertiary sedimentary rocks of northeastern Washington. This project involved measurement and sampling of surface sections, collection of samples from isolated outcrops, and chemical and mineralogical analyses of samples. No portion of the project area of this report is rated of high or of medium favorability for potential uranium resources. Low favorability ratings are given to Oroville, Tonasket, and Pine Creek areas of the Okanogan River valley; to the Republic graben; and to the William Lakes, Colville, and Sheep Creek areas of the upper Columbia River valley. All these areas contain some fluvial, poorly sorted feldspathic or arkosic sandstones and conglomerates. These rocks are characterized by very low permeability and a consistently high siliceous matrix suggesting very low initial permeability. There are no known uranium deposits in any of these areas, and low level uranium anomalies are rare

  4. The effect of "in favor of myself": preventive program to enhance positive self and body image among adolescents.

    Science.gov (United States)

    Golan, Moria; Hagay, Noaa; Tamir, Snait

    2013-01-01

    Positive self-esteem, emotional well-being, school achievements and family connectedness are considered protective factors against health-compromising behaviors. This study examined the effect of an interactive, community-based, media literacy and dissonance wellness program, In Favor of Myself, on the self-image, body image, eating attitudes and behavior of young adolescents. A preliminary cohort study was conducted among 972 program participants who did not take part in the controlled trial. Over 75% of participants said they would recommend the program to their friends. A controlled trial was conducted to evaluate program acceptability, efficacy and effectiveness among 259 participants (210 in the intervention group and 49 in the control group), aged 12-14 years, who completed questionnaires during at least two assessment times. Program materials were provided, along with leaders' training, in order to ensure quality program delivery and creation of a wide network of committed program leaders. The program significantly reduced drive for thinness and self-worth contingent upon others' approval, the gap between current body figure and ideal figure, and the impact of mood on girls' self-image. Superiority was found among those participating in the intervention group with respect to recognizing media strategies, the influence of media on desire to change, and the influence of appearance on self-confidence and drive for thinness. In Favor of Myself shows promising results for strengthening adolescents' ability to cope with the challenges of their life stage. Suggestions for improving In Favor of Myself are presented.

  5. Large Mode Area Single Trench Fiber for 2 mu m Operation

    DEFF Research Database (Denmark)

    Jain, Deepak; Sahu, Jayanta K.

    2016-01-01

    to 25 cm bend radius, respectively, by exploiting high delocalization of the higher order modes. Achievement of a large effective-area can be very useful to address nonlinear effects. Moreover, single trench fiber offers certain advantages such as low-cost fabrication and easy postprocessing (such......Performance of single trench fibers has been investigated using finite-element method at 2 mu m wavelength. Numerical investigations show that an effective single mode operation for large effective area between 3000-4000 mu m(2) and 2000-3000 mu m(2) can be achieved at similar to 40 and similar...... as cleaving and splicing) thanks to the all-solid fiber design....

  6. Operating Cigeo

    International Nuclear Information System (INIS)

    Launeau, F.

    2016-01-01

    The CIGEO facility dedicated to the geological disposal of high- and intermediate-level radioactive wastes will be composed of 2 parts: an underground facility at a depth of 500 m to dispose the waste packages in tunnels and a surface facility to take delivery of the wastes and prepare the packages. The underground facility will be built progressively and will cover a surface of 15 km 2 at the end of Cigeo operating-life. A large part of the surface facility (located a few km away from the waste reception place) will be dedicated to the works led deep underground to build the tunnels and will receive drilling cuttings. The article describes also the ramp and carts to lead waste packages underground. Most of the operations will be automated. The definitive closure of the tunnels will be made with swelling clay and concrete plugs. (A.C.)

  7. Operative Links

    DEFF Research Database (Denmark)

    Wistoft, Karen; Højlund, Holger

    2012-01-01

    educational approaches. Methods: Mixed qualitative design: survey based on telephone interviews with health managers (n=72), personal and focus group interviews with health professionals (n=84) and pupils (n=108) from 18 school classes, and comparative case studies in five selected municipalities of various...... educational goals, learning content, or value clarification. Health pedagogy is often a matter of retrospective rationalization rather than the starting point of planning. Health and risk behaviour approaches override health educational approaches. Conclusions: Operational links between health education...

  8. Operation Poorman

    International Nuclear Information System (INIS)

    Pruvost, N.; Tsitouras, J.

    1981-01-01

    The objectives of Operation Poorman were to design and build a portable seismic system and to set up and use this system in a cold-weather environment. The equipment design uses current technology to achieve a low-power, lightweight system that is configured into three modules. The system was deployed in Alaska during wintertime, and the results provide a basis for specifying a mission-ready seismic verification system

  9. Reactor operator screening test experiences

    International Nuclear Information System (INIS)

    O'Brien, W.J.; Penkala, J.L.; Witzig, W.F.

    1976-01-01

    When it became apparent to Duquesne Light Company of Pittsburgh, Pennsylvania, that the throughput of their candidate selection-Phase I training-reactor operator certification sequence was something short of acceptable, the utility decided to ask consultants to make recommendations with respect to candidate selection procedures. The recommendation implemented was to create a Nuclear Training Test that would predict the success of a candidate in completing Phase I training and subsequently qualify for reactor operator certification. The mechanics involved in developing and calibrating the Nuclear Training Test are described. An arbitration decision that resulted when a number of International Brotherhood of Electrical Workers union employees filed a grievance alleging that the selection examination was unfair, invalid, not job related, inappropriate, and discriminatorily evaluated is also discussed. The arbitration decision favored the use of the Nuclear Training Test

  10. EAM-based high-speed 100-km OFDM transmission featuring tolerant modulator operation enabled using SSII cancellation.

    Science.gov (United States)

    Chen, Hsing-Yu; Wei, Chia-Chien; Lu, I-Cheng; Chen, Yu-Chao; Chu, Hsuan-Hao; Chen, Jyehong

    2014-06-16

    In this study, a technique was developed to compensate for nonlinear distortion through cancelling subcarrier-to-subcarrier intermixing interference (SSII) in an electroabsorption modulator (EAM)-based orthogonal frequency-division multiplexing (OFDM) transmission system. The nonlinear distortion to be compensated for is induced by both EAM nonlinearity and fiber dispersion. Because an OFDM signal features an inherently high peak-to-average power ratio, a trade-off exists between the optical modulation index (OMI) and modulator nonlinearity. Therefore, the nonlinear distortion limits the operational tolerance of the bias voltage and the driving power to a small region. After applying the proposed SSII cancellation, the OMI of an OFDM signal was increased yielding only a small increment of nonlinear distortion, and the tolerance region of the operational conditions was also increased. By employing the proposed scheme, this study successfully demonstrates 50-Gbps OFDM transmission over 100-km dispersion-uncompensated single-mode fiber based on a single 10-GHz EAM.

  11. Operator-sum representation for bosonic Gaussian channels

    International Nuclear Information System (INIS)

    Ivan, J. Solomon; Sabapathy, Krishna Kumar; Simon, R.

    2011-01-01

    Operator-sum or Kraus representations for single-mode bosonic Gaussian channels are developed, and several of their consequences explored. The fact that the two-mode metaplectic operators acting as unitary purification of these channels do not, in their canonical form, mix the position and momentum variables is exploited to present a procedure which applies uniformly to all families in the Holevo classification. In this procedure the Kraus operators of every quantum-limited Gaussian channel can be simply read off from the matrix elements of a corresponding metaplectic operator. Kraus operators are employed to bring out, in the Fock basis, the manner in which the antilinear, unphysical matrix transposition map when accompanied by injection of a threshold classical noise becomes a physical channel, denoted D(κ) in the Holevo classification. The matrix transposition channels D(κ), D(κ -1 ) turn out to be a dual pair in the sense that their Kraus operators are related by the adjoint operation. The amplifier channel with amplification factor κ and the beam-splitter channel with attenuation factor κ -1 turn out to be mutually dual in the same sense. The action of the quantum-limited attenuator and amplifier channels as simply scaling maps on suitable quasiprobabilities in phase space is examined in the Kraus picture. Consideration of cumulants is used to examine the issue of fixed points. The semigroup property of the amplifier and attenuator families leads in both cases to a Zeno-like effect arising as a consequence of interrupted evolution. In the cases of entanglement-breaking channels a description in terms of rank 1 Kraus operators is shown to emerge quite simply. In contradistinction, it is shown that there is not even one finite rank operator in the entire linear span of Kraus operators of the quantum-limited amplifier or attenuator families, an assertion far stronger than the statement that these are not entanglement breaking channels. A characterization of

  12. Operative links

    DEFF Research Database (Denmark)

    Wistoft, Karen

    2010-01-01

    and have been the object of great expectations concerning the ability to incorporate health concerns into every welfare area through health promotion strategies. The paper draws on results and analyses of a collective research project funded by the Danish National Research Council and carried out...... as networks: second, a semantic perspective on discourses and concepts of health, and, third, a health pedagogical perspective on participation, intervention, and roles. This paper argues for the importance of 'operative links' between different levels in health strategies. It is proposed that such links...

  13. Gender related differences in response to "in favor of myself" wellness program to enhance positive self & body image among adolescents.

    Directory of Open Access Journals (Sweden)

    Moria Golan

    Full Text Available BACKGROUND: Physical, neurological and psychological changes are often experienced differently by male and female adolescents. Positive self-esteem, emotional well-being, school achievements, and family connectedness are considered as protective factors against health-compromising behaviors. This study examines the gender differences in respect to the effect of a school-based interactive wellness program--"In Favor of Myself"--on self-image, body image, eating attitudes and behaviors of young adolescents. METHODS: Two hundred and ten adolescents (mean age 13.5 participated in the intervention group, 55% were girls and 45% boys. Program consisted of eight 90-minutes structured sessions integrated into a regular school coping skills curriculum. The program focused on self-esteem, self-image, body image, media literacy and cognitive dissonance. The overall impact of the program and the study protocol were previously published. RESULTS: Overall, there are gender related differences in respect to body image and self-image in young adolescents in response to "In Favor of Myself". Compared to boys, girls reported at baseline higher self-esteem, being more contingent by appearance, and their self-image was more influenced by popularity, appearance, interpersonal communication and admired people. Furthermore girls presented greater gap between current body figure and perceived ideal figure. Not only were girls more dissatisfied with their body, but they were more active in attempts to become and/or remain "thin". At program termination, gender × time effect was detected in reduction of self-worth contingent by others, change in importance given to achievements at schools, parents' perceptions, as well as the impact of comparisons to friends and family members on self-image. CONCLUSIONS: Girls exhibited more gains than boys from 'In Favor of Myself' which raise the questions about how effective would be the program when delivered in mixed gender groups

  14. Gender related differences in response to "in favor of myself" wellness program to enhance positive self & body image among adolescents.

    Science.gov (United States)

    Golan, Moria; Hagay, Noa; Tamir, Snait

    2014-01-01

    Physical, neurological and psychological changes are often experienced differently by male and female adolescents. Positive self-esteem, emotional well-being, school achievements, and family connectedness are considered as protective factors against health-compromising behaviors. This study examines the gender differences in respect to the effect of a school-based interactive wellness program--"In Favor of Myself"--on self-image, body image, eating attitudes and behaviors of young adolescents. Two hundred and ten adolescents (mean age 13.5) participated in the intervention group, 55% were girls and 45% boys. Program consisted of eight 90-minutes structured sessions integrated into a regular school coping skills curriculum. The program focused on self-esteem, self-image, body image, media literacy and cognitive dissonance. The overall impact of the program and the study protocol were previously published. Overall, there are gender related differences in respect to body image and self-image in young adolescents in response to "In Favor of Myself". Compared to boys, girls reported at baseline higher self-esteem, being more contingent by appearance, and their self-image was more influenced by popularity, appearance, interpersonal communication and admired people. Furthermore girls presented greater gap between current body figure and perceived ideal figure. Not only were girls more dissatisfied with their body, but they were more active in attempts to become and/or remain "thin". At program termination, gender × time effect was detected in reduction of self-worth contingent by others, change in importance given to achievements at schools, parents' perceptions, as well as the impact of comparisons to friends and family members on self-image. Girls exhibited more gains than boys from 'In Favor of Myself' which raise the questions about how effective would be the program when delivered in mixed gender groups vs. mono-gender groups.

  15. The effect of "in favor of myself": preventive program to enhance positive self and body image among adolescents.

    Directory of Open Access Journals (Sweden)

    Moria Golan

    Full Text Available BACKGROUND: Positive self-esteem, emotional well-being, school achievements and family connectedness are considered protective factors against health-compromising behaviors. This study examined the effect of an interactive, community-based, media literacy and dissonance wellness program, In Favor of Myself, on the self-image, body image, eating attitudes and behavior of young adolescents. A preliminary cohort study was conducted among 972 program participants who did not take part in the controlled trial. Over 75% of participants said they would recommend the program to their friends. METHODS: A controlled trial was conducted to evaluate program acceptability, efficacy and effectiveness among 259 participants (210 in the intervention group and 49 in the control group, aged 12-14 years, who completed questionnaires during at least two assessment times. Program materials were provided, along with leaders' training, in order to ensure quality program delivery and creation of a wide network of committed program leaders. RESULTS: The program significantly reduced drive for thinness and self-worth contingent upon others' approval, the gap between current body figure and ideal figure, and the impact of mood on girls' self-image. Superiority was found among those participating in the intervention group with respect to recognizing media strategies, the influence of media on desire to change, and the influence of appearance on self-confidence and drive for thinness. CONCLUSIONS: In Favor of Myself shows promising results for strengthening adolescents' ability to cope with the challenges of their life stage. Suggestions for improving In Favor of Myself are presented.

  16. Asymmetric C-C Bond-Formation Reaction with Pd: How to Favor Heterogeneous or Homogeneous Catalysis?

    DEFF Research Database (Denmark)

    Reimann, S.; Grunwaldt, Jan-Dierk; Mallat, T.

    2010-01-01

    BINAP plays a dual role: a considerable coverage of the Pd surface by the bulky compound slows down the initial reduction of the surface oxides but BINAP itself may consume surface oxygen (through its conversion to BINAPO and BINAPO(2)) and contribute to the maintenance of the active metal surface...... is a clear deviation from the behavior of the corresponding homogeneous system. In contrast, halogenated solvents are easily dehalogenated on Pd/Al2O3 and thus they favor leaching of the metal and formation of soluble compounds, analogous to classical metal corrosion in the presence of halide ions...

  17. Recurrent DGCR8, DROSHA, and SIX homeodomain mutations in favorable histology Wilms tumors | Office of Cancer Genomics

    Science.gov (United States)

    We report the most common single-nucleotide substitution/deletion mutations in favorable histology Wilms tumors (FHWTs) to occur within SIX1/2 (7% of 534 tumors) and microRNA processing genes (miRNAPGs) DGCR8 and DROSHA (15% of 534 tumors). Comprehensive analysis of 77 FHWTs indicates that tumors with SIX1/2 and/or miRNAPG mutations show a pre-induction metanephric mesenchyme gene expression pattern and are significantly associated with both perilobar nephrogenic rests and 11p15 imprinting aberrations.

  18. Em favor da talassografia

    Directory of Open Access Journals (Sweden)

    Jean-Louis Boudou

    2001-01-01

    Full Text Available A Talassografia (“descrição do mar” interessa-sepelos impactos físicos, biológicos, ecológicos... culturais da violenta antropização dos ambientes costeiros (oceânicos e continentais, caracterizados pelaexigüidade, vulnerabilidade, fragilidade e plasticidade. Como o Brasil é um “país marítimo”, os geó-grafos (os talassógrafos brasileiros são convidadosa intensificar suas pesquisas nas áreas costeiras e acriar novas estruturas para divulgá-las: Revista, Encontros, Associação, Pós-Graduação... tudo em prolda talassografia.

  19. A Favor del Plagio

    Directory of Open Access Journals (Sweden)

    Manuel Arranz

    2007-11-01

    Full Text Available Yo no tengo nada contra el plagio. Ustedes, como lectores, seguramente tampoco. Bueno, tal vez prejuicios. Es lógico que los tengan con tanto artículo condenándolo. Hasta ahora, que yo sepa, nadie ha escrito para defenderlo. Los que sí tienen algo, parece ser, son los autores. Una minoría al fin y al cabo. Ya sé que hay que respetar el derecho de las minorías, pero el asunto del plagio, como tantos otros, deberíamos examinarlo con más detalle, y preguntarnos, por ejemplo, ¿por qué se molestan tanto los autores cuando les plagian? ¿En nombre de qué?, sería también una buena pregunta. No me irán a decir a estas alturas que en nombre de la comunidad científica. A fin de cuentas el plagio beneficia la difusión de la ciencia. Los autores se molestan en nombre propio. Naturalmente tienen su derecho, no se lo vamos a discutir, pero, ¿no demuestra eso cierto narcisismo impropio de un científico? ¿La ciencia no es de todos?, como suelen decir en otras ocasiones.

  20. A favor del Plagio

    OpenAIRE

    Manuel Arranz

    2007-01-01

    Yo no tengo nada contra el plagio. Ustedes, como lectores, seguramente tampoco. Bueno, tal vez prejuicios. Es lógico que los tengan con tanto artículo condenándolo. Hasta ahora, que yo sepa, nadie ha escrito para defenderlo. Los que sí tienen algo, parece ser, son los autores. Una minoría al fin y al cabo. Ya sé que hay que respetar el derecho de las minorías, pero el asunto del plagio, como tantos otros, deberíamos examinarlo con más detalle, y preguntarnos, por ejemplo, ¿por qué se molestan...

  1. Toque, por favor

    Directory of Open Access Journals (Sweden)

    Terry caesar

    2011-05-01

    Full Text Available

    Este artigo discute como, na sociedade brasileira, as pessoas tendem a se tocarem em publico mais livremente que em outras sociedades. Usando vários casos, o artigo explora as maneiras que os homens se cumprimentam, como as mulheres se abraçam e beijam, como os filhos se relacionam com suas mães, e mesmo como dentro da mesma sociedade hábitos e costumes relacionados ao toque físico mudam com o tempo.

  2. Operator errors

    International Nuclear Information System (INIS)

    Knuefer; Lindauer

    1980-01-01

    Besides that at spectacular events a combination of component failure and human error is often found. Especially the Rasmussen-Report and the German Risk Assessment Study show for pressurised water reactors that human error must not be underestimated. Although operator errors as a form of human error can never be eliminated entirely, they can be minimized and their effects kept within acceptable limits if a thorough training of personnel is combined with an adequate design of the plant against accidents. Contrary to the investigation of engineering errors, the investigation of human errors has so far been carried out with relatively small budgets. Intensified investigations in this field appear to be a worthwhile effort. (orig.)

  3. Hassab’s operation for Joubert syndrome with congenital hepatic fibrosis: A case report

    Directory of Open Access Journals (Sweden)

    Koji Miyazawa

    2017-01-01

    Conclusion: This is the first case report of Hassab’s operation for congenital hepatic fibrosis in a patient with Joubert syndrome, a rare congenital condition. We achieved a favorable clinical outcome.

  4. Evaluating the importance of convective intensity and symmetry as predictors of TC intensity change for a large database of storms in favorable environments

    Science.gov (United States)

    Alvey, G., III; Zawislak, J.; Zipser, E. J.

    2014-12-01

    Despite operational advances in tropical cyclone track forecasts, progress towards improving forecasts of intensity change has been more limited. Previous studies have separately quantified the importance of environmental conditions and convective properties with respect to intensity change; however, conjoined analyses have been rare. Using 15 years (1998-2012) of SHIPS and NCEP FNL reanalysis information for Atlantic and East Pacific storms, we analyze the sensitivity of intensity change for a detailed set of environmental parameters. Environmental conditions are then used to determine a threshold beyond which intensification is plausible. In conjunction with the environmental dataset, an expansive collection of passive microwave satellite (includes TMI, AMSR-E, and SSMI[S]) and TRMM Precipitation Radar (PR) data is used to investigate the relative importance of various convective properties (specifically those proxies for convective intensity, symmetry, and area) in storms that meet the "plausible" threshold. An emphasis is placed on evaluating the hypothesis that, when a necessary set of environmental conditions is met, intensification is favored if the inner core consists of symmetric, moderately intense convection.

  5. Graft-to-recipient weight ratio lower to 0.7% is safe without portal pressure modulation in right-lobe living donor liver transplantation with favorable conditions.

    Science.gov (United States)

    Lee, Seung Duk; Kim, Seong Hoon; Kim, Young-Kyu; Lee, Soon-Ae; Park, Sang-Jae

    2014-02-01

    The low graft-to-recipient weight ratio (GRWR) in adult-to-adult living donor liver transplantation (LDLT) is one of the major risk factors affecting graft survival. The goal of this study was to evaluate whether the lower limit of the GRWR can be safely reduced without portal pressure modulation in right-lobe LDLT. From 2005 to 2011, 317 consecutive patients from a single institute underwent LDLT with right-lobe grafts without portal pressure modulation. Of these, 23 had a GRWR of less than 0.7% (group A), 27 had a GRWR of ≥0.7%, recipient, donor, operation factors, laboratory findings and complications were reviewed retrospectively. The baseline demographics showed low model for end-stage liver disease score (mean 16.3+/-8.9) and high percentage of hepatocellular carcinoma (231 patients, 72.9%). Three groups by GRWR demonstrated similar characteristics except recipient body mass index and donor gender. For small-for-size syndrome, there were 3 (13.0%) in group A, 1 (3.7%) in group B, and 2 patients (0.7%) in group C (Pneed to modulate portal pressure in adult-to-adult LDLT using the right-lobe in favorable conditions including low model for end-stage liver disease score.

  6. Atomistic modeling to investigate the favored composition for metallic glass formation in the Ca-Mg-Ni ternary system.

    Science.gov (United States)

    Zhao, S; Li, J H; An, S M; Li, S N; Liu, B X

    2017-05-17

    A realistic interatomic potential was first constructed for the Ca-Mg-Ni system and then applied to Monte Carlo simulations to predict the favored composition for metallic glass formation in the ternary system. The simulations not only predict a hexagonal composition region, within which the Ca-Mg-Ni metallic glass formation is energetically favored, but also pinpoint an optimized sub-region within which the amorphization driving force, i.e. the energy difference between the solid solution and disordered phase, is larger than that outside. The simulations further reveal that the physical origin of glass formation is the solid solution collapsing when the solute atom exceeds the critical solid solubility. Further structural analysis indicates that the pentagonal bi-pyramids dominate in the optimized sub-region. The large atomic size difference between Ca, Mg and Ni extends the short-range landscape and facilitates the development of a hybridized packing model in the medium-range, and eventually enhancing the glass formation in the system. The predictions are well supported by the experimental observations reported so far, and could be of help for designing the ternary glass formation.

  7. Continuous Quality Improvement Efforts Increase Survival with Favorable Neurologic Outcome after Out-of-hospital Cardiac Arrest.

    Science.gov (United States)

    Sporer, Karl; Jacobs, Michael; Derevin, Leo; Duval, Sue; Pointer, James

    2017-01-01

    To assess system-wide implementation of specific therapies focused on perfusion during cardiopulmonary resuscitation (CPR) and cerebral recovery after Return of Spontaneous Circulation (ROSC). Before and after retrospective analysis of an out-of-hospital cardiac arrest database. Implementation trial in the urban/suburban community of Alameda County, California, USA, population 1.6 million, from November 2009-December 2012. Adult patients with non-traumatic out-of-hospital cardiac arrest (OHCA) who received CPR and/or defibrillation. The impedance threshold device was used throughout this study and there was an increased use of mechanical CPR (mCPR) and in-hospital therapeutic hypothermia (HTH). Rates of ROSC, survival to hospital discharge and Cerebral Performance Category (CPC) scores were compared using univariate and multivariable analyses. A total of 2,926 adult non-traumatic patients with OHCA received CPR during the study period. From 2009-2011 to 2012, there was an increase in ROSC from 29.0% to 34.4% (p = 0.003) and a non-significant increase in hospital discharge from 10.2% to 12.0% (p = 0.16). There was a 76% relative increase in survival with favorable neurologic function between the two periods, as determined by CPC ≤ 2, from 4.5% to 7.9% (unadjusted OR = 1.80; CI = 1.31, 2.48; p improved survival by 74% with favorable neurologic function following OHCA.

  8. Impact of collateral circulation status on favorable outcomes in thrombolysis treatment: A systematic review and meta-analysis.

    Science.gov (United States)

    Wufuer, Alimu; Wubuli, Atikaimu; Mijiti, Peierdun; Zhou, Jun; Tuerxun, Shabier; Cai, Jian; Ma, Jianhua; Zhang, Xiaoning

    2018-01-01

    Collateral circulation affects the prognosis of patients with acute ischemic stroke (AIS) treated by thrombolysis. The present study performed a systematic assessment of the impact of the collateral circulation status on the outcomes of patients receiving thrombolysis treatment. Relevant full-text articles from the Cochrane Library, Ovid, Medline, Embase and PubMed databases published from January 1, 2000 to November 1, 2016 were retrieved. The quality of the studies was assessed and data were extracted by 2 independent investigators. The random-effects model was used to estimate the impact of good vs. poor collateral circulation, as well as baseline characteristics, on the outcome within the series presented as risk ratios. Subgroup analyses explored the potential factors that may interfere with the effects of the collateral circulation status on the outcome. A total of 29 studies comprising 4,053 patients were included in the present meta-analysis. A good collateral circulation status was revealed to have a beneficial effect on favorable functional outcome (modified Rankin scale, 0-3 at 3-6 months; Pcollateral circulation. Good collateral circulation was also associated with a lower rate of symptomatic intracranial hemorrhage (Pcollateral circulation was demonstrated to have a favorable prognostic value regarding the outcome for patients with AIS receiving thrombolysis treatment. Assessment of collateral circulation and penumbra area during pre-treatment imaging within an appropriate time-window prior to thrombolytic therapy will therefore improve the identification of AIS patients who may benefit from thrombolysis treatment.

  9. Ohtahara syndrome or early-onset West syndrome? A case with overlapping features and favorable response to vigabatrin.

    Science.gov (United States)

    Korff, Christian M; Vulliemoz, Serge; Picard, Fabienne; Fluss, Joel

    2012-11-01

    The so called "severe neonatal epilepsies with suppression-burst pattern" include early infantile epileptic encephalopathy, and early myoclonic encephalopathy. Both syndromes are characterized by pharmacoresistant seizures that appear in the first weeks (up to the third month) of life, an electroencephalographic suppression-burst pattern, and a grim prognosis. Many patients later present with other forms of epileptic encephalopathies with difficult-to-treat seizures, such as West syndrome, and those who survive usually suffer from severe neurodevelopmental troubles. We here report the case of a patient who presented at our center with features consistent with a mixed form of these epileptic encephalopathies, and favorable neurodevelopmental evolution. To draw attention on the potentially favorable effect of vigabatrin in early-onset epileptic encephalopathies. Case study. In our patient, seizures immediately stopped upon initiation of vigabatrin treatment, and his development and neurological examination at one year are normal. Vigabatrin should be considered as an early treatment option in early-onset epileptic encephalopathies. Copyright © 2012 European Paediatric Neurology Society. Published by Elsevier Ltd. All rights reserved.

  10. A large cohort study reveals the association of elevated peripheral blood lymphocyte-to-monocyte ratio with favorable prognosis in nasopharyngeal carcinoma.

    Directory of Open Access Journals (Sweden)

    Jing Li

    Full Text Available BACKGROUND: Nasopharyngeal carcinoma (NPC is an endemic neoplasm in southern China. Although NPC sufferers are sensitive to radiotherapy, 20-30% of patients finally progress with recurrence and metastases. Elevated lymphocyte-to-monocyte ratio (LMR has been reported to be associated with favorable prognosis in some hematology malignancies, but has not been studied in NPC. The aim of this study was to evaluate whether LMR could predict the prognosis of NPC patients. METHODS: A retrospective cohort of 1,547 non-metastatic NPC patients was recruited between January 2005 and June 2008. The counts for peripheral lymphocyte and monocyte were retrieved, and the LMR was calculated. Receiver operating characteristic curve analysis, univariate and multivariate COX proportional hazards analyses were applied to evaluate the associations of LMR with overall survival (OS, disease-free survival (DFS, distant metastasis-free survival (DMFS and loco-regional recurrence-free survival (LRRFS, respectively. RESULTS: Univariate analysis revealed that higher LMR level (≥ 5.220 was significantly associated with superior OS, DFS and DMFS (P values <0.001. The higher lymphocyte count (≥ 2.145 × 10(9/L was significantly associated with better OS (P = 0.002 and DMFS (P = 0.031, respectively, while the lower monocyte count (<0.475 × 10(9/L was associated with better OS (P = 0.012, DFS (P = 0.011 and DMFS (P = 0.003, respectively. Multivariate Cox proportional hazard analysis showed that higher LMR level was a significantly independent predictor for superior OS (hazard ratio or HR = 0.558, 95% confidence interval or 95% CI = 0.417-0.748; P<0.001, DFS (HR = 0.669, 95% CI = 0.535-0.838; P<0.001 and DMFS (HR = 0.543, 95% CI = 0.403-0.732; P<0.001, respectively. The advanced T and N stages were also independent indicators for worse OS, DFS, and DMFS, except that T stage showed borderline statistical significance for DFS (P = 0.053 and DMFS (P = 0.080. CONCLUSIONS: The

  11. 486nm blue laser operating at 500 kHz pulse repetition frequency

    Science.gov (United States)

    Creeden, Daniel; Blanchard, Jon; Pretorius, Herman; Limongelli, Julia; Setzler, Scott D.

    2016-03-01

    Compact, high power blue light in the 470-490nm region is difficult to generate due to the lack of laser sources which are easily convertible (through parametric processes) to those wavelengths. By using a pulsed Tm-doped fiber laser as a pump source for a 2-stage second harmonic generation (SHG) scheme, we have generated ~2W of 486.5nm light at 500kHz pulse repetition frequency (PRF). To our knowledge, this is the highest PRF and output power achieved in the blue region based on a frequency converted, monolithic fiber laser. This pump laser is a pulsed Tm-doped fiber laser/amplifier which generates 12.8W of 1946nm power at 500kHz PRF with diffraction-limited output from a purely single-mode fiber. The output from this laser is converted to 973nm through second harmonic generation (SHG). The 973nm is then converted to 486.5nm via another SHG stage. This architecture operates with very low peak power, which can be challenging from a nonlinear conversion standpoint. However, the low peak power enables the use of a single-mode monolithic fiber amplifier without undergoing nonlinear effects in the fiber. This also eliminates the need for novel fiber designs, large-mode area fiber, or free-space coupling to rod-type amplifiers, improving reliability and robustness of the laser source. Higher power and conversion efficiency are possible through the addition of Tm-doped fiber amplification stages as well as optimization of the nonlinear conversion process and nonlinear materials. In this paper, we discuss the laser layout, results, and challenges with generating blue light using a low peak power approach.

  12. Fewer peripheral asymmetrical cortical veins is a predictor of favorable outcome in MCA infarctions with SWI-DWI mismatch.

    Science.gov (United States)

    Yuan, Tao; Ren, Guoli; Quan, Guanmin; Gao, Duo

    2018-02-09

    Outcome prediction of asymmetrical prominent cortical veins (APCVs) on infarction is still debated and may help in selecting patients for reperfusion treatment. To explore the relationship between fewer peripheral APCVs and the outcome in the patients of acute/subacute middle cerebral artery (MCA) infarctions as well as the relationship between this sign and stenosis of ipsilateral MCA. Retrospective case-control study. We enrolled 41 patients with MCA acute/subacute infarction. Compared to the low sign of cortical veins of contralateral hemisphere on susceptibility-weighted imaging (SWI), these patients were divided into fewer (n = 28) and prominent APCVs (n = 13) groups. 3.0T conventional stroke sequences, including T 1 -weighted imaging, T 2 -weighted imaging, fluid-attenuated inversion recovery (FLAIR), diffusion-weighted imaging (DWI) (b = 0 and 1000 s/mm 2 ), MR angiography (MRA), and SWI. We explored the relationships between fewer peripheral APCVs sign and clinical outcome, as well as the relationship between this sign and the degree of ipsilateral MCA stenosis. Fisher's exact analysis, logistical regression, as well as Cohen's kappa coefficient were used for statistical analysis. Fewer and prominent peripheral APCVs were detected in 28 (56.10%) and 13 (43.90%) patients. In 28 patients with fewer peripheral APCVs, 23 patients (82.14%) had a favorable outcome (modified Rankin Scale [mRS] ≤2), and five patients (17.76%) had an unfavorable outcome (mRS >2) (P = 0.010). In terms of MCA stenosis, the rate of normal and mild to moderate stenosis of MCA in the fewer APCVs group (82.14%) was higher than that in the prominent APCVs group (23.08%) (P < 0.001). More severe stenosis of ipsilateral MCA was found in patients with prominent APCVs group (76.92%) than that of fewer APCVs group (17.86%). The peripheral APCVs was positively correlated with the degree of MCA stenosis (r = 0.538, P < 0.001). Fewer peripheral APCVs may suggest a

  13. MYC-driven epigenetic reprogramming favors the onset of tumorigenesis by inducing a stem cell-like state.

    Science.gov (United States)

    Poli, Vittoria; Fagnocchi, Luca; Fasciani, Alessandra; Cherubini, Alessandro; Mazzoleni, Stefania; Ferrillo, Sara; Miluzio, Annarita; Gaudioso, Gabriella; Vaira, Valentina; Turdo, Alice; Giaggianesi, Miriam; Chinnici, Aurora; Lipari, Elisa; Bicciato, Silvio; Bosari, Silvano; Todaro, Matilde; Zippo, Alessio

    2018-03-09

    Breast cancer consists of highly heterogeneous tumors, whose cell of origin and driver oncogenes are difficult to be uniquely defined. Here we report that MYC acts as tumor reprogramming factor in mammary epithelial cells by inducing an alternative epigenetic program, which triggers loss of cell identity and activation of oncogenic pathways. Overexpression of MYC induces transcriptional repression of lineage-specifying transcription factors, causing decommissioning of luminal-specific enhancers. MYC-driven dedifferentiation supports the onset of a stem cell-like state by inducing the activation of de novo enhancers, which drive the transcriptional activation of oncogenic pathways. Furthermore, we demonstrate that the MYC-driven epigenetic reprogramming favors the formation and maintenance of tumor-initiating cells endowed with metastatic capacity. This study supports the notion that MYC-driven tumor initiation relies on cell reprogramming, which is mediated by the activation of MYC-dependent oncogenic enhancers, thus establishing a therapeutic rational for treating basal-like breast cancers.

  14. Human oocytes. Error-prone chromosome-mediated spindle assembly favors chromosome segregation defects in human oocytes.

    Science.gov (United States)

    Holubcová, Zuzana; Blayney, Martyn; Elder, Kay; Schuh, Melina

    2015-06-05

    Aneuploidy in human eggs is the leading cause of pregnancy loss and several genetic disorders such as Down syndrome. Most aneuploidy results from chromosome segregation errors during the meiotic divisions of an oocyte, the egg's progenitor cell. The basis for particularly error-prone chromosome segregation in human oocytes is not known. We analyzed meiosis in more than 100 live human oocytes and identified an error-prone chromosome-mediated spindle assembly mechanism as a major contributor to chromosome segregation defects. Human oocytes assembled a meiotic spindle independently of either centrosomes or other microtubule organizing centers. Instead, spindle assembly was mediated by chromosomes and the small guanosine triphosphatase Ran in a process requiring ~16 hours. This unusually long spindle assembly period was marked by intrinsic spindle instability and abnormal kinetochore-microtubule attachments, which favor chromosome segregation errors and provide a possible explanation for high rates of aneuploidy in human eggs. Copyright © 2015, American Association for the Advancement of Science.

  15. Residual structure of Streptococcus mutans biofilm following complete disinfection favors secondary bacterial adhesion and biofilm re-development.

    Directory of Open Access Journals (Sweden)

    Tatsuya Ohsumi

    Full Text Available Chemical disinfection of oral biofilms often leaves biofilm structures intact. This study aimed to examine whether the residual structure promotes secondary bacterial adhesion. Streptococcus mutans biofilms generated on resin-composite disks in a rotating disc reactor were disinfected completely with 70% isopropyl alcohol, and were again cultured in the same reactor after resupplying with the same bacterial solution. Specimens were subjected to fluorescence confocal laser scanning microscopy, viable cell counts and PCR-Invader assay in order to observe and quantify secondarily adhered cells. Fluorescence microscopic analysis, particularly after longitudinal cryosectioning, demonstrated stratified patterns of viable cells on the disinfected biofilm structure. Viable cell counts of test specimens were significantly higher than those of controls, and increased according to the amount of residual structure and culture period. Linear regression analysis exhibited a high correlation between viable and total cell counts. It was concluded that disinfected biofilm structures favored secondary bacterial adhesion.

  16. Estado neoliberal y acumulación por desposesión a favor del capital glocal financiero

    Directory of Open Access Journals (Sweden)

    Marco Antonio Merchand Rojas

    2012-12-01

    Full Text Available El objetivo general de este trabajo es analizar por qué la acumulación por desposesión es una de lasmodalidades que se implementan indiscriminadamente en todos los órdenes de la economía mundial y representa la mejor forma para estabilizar el sistema capitalista a favor del capital financiero y en contra de la fuerza de trabajo. Las condiciones en que el capital se impone en cada espacio económico difieren en sus métodos y maneras de reproducirse; no obstante su carácter intrínseco de enajenar o externalizar lo internalizado en beneficio de pocos (sobre todo, de los dueños del capital se aplica por igual en todos los países, independientemente de si estamos hablado de un país de grado alto o bajo de desarrollo

  17. Oral terbinafine and itraconazole treatments against dermatophytes appear not to favor the establishment of Fusarium spp. in nail.

    Science.gov (United States)

    Verrier, Julie; Bontems, Olympia; Baudraz-Rosselet, Florence; Monod, Michel

    2014-01-01

    Fusarium onychomycoses are weakly responsive or unresponsive to standard onychomycosis treatments with oral terbinafine and itraconazole. To examine whether the use of terbinafine and itraconazole, which are highly effective in fighting Trichophyton onychomycoses, could be a cause of the high incidence of Fusarium nail infections. Polymerase chain reaction methods were used to detect both Fusarium spp. and Trichophyton spp. in nails of patients who had either received treatment previously or not. No significant microbiological differences were found between treated and untreated patients. In 24 of 79 cases (30%), Fusarium spp. was detected in samples of patients having had no previous antifungal therapy and when Trichophyton spp. grew in culture. Oral terbinafine and itraconazole treatments do not appear to favor the establishment of Fusarium spp. in onychomycosis. © 2014 S. Karger AG, Basel.

  18. Didactic interdisciplinary tasks, in order to favor the permanent formation of the teacher of the Natural Sciences in Adult Education

    Directory of Open Access Journals (Sweden)

    Elieser Briso-González

    2017-07-01

    Full Text Available The article exposes a system of didactic interdisciplinary tasks, that when discussing the way of how establishing didactic links between the biological, geographic and chemicals contents, through the dynamics of the methodological work; It is tried to favor the permanent formation of the teachers of the subjects of study in the area of Natural Sciences in Adult Education, and to get close to the students to an adequate understanding of the complex phenomena of his surroundings. The discreet results attained with this in the process of teaching learning of this education, they reflect the pertinence of a most integrative vision in the process of scientific present-day education, which are related with the integration of the advances of sciences and technology.

  19. Annealing to sequences within the primer binding site loop promotes an HIV-1 RNA conformation favoring RNA dimerization and packaging

    Science.gov (United States)

    Seif, Elias; Niu, Meijuan; Kleiman, Lawrence

    2013-01-01

    The 5′ untranslated region (5′ UTR) of HIV-1 genomic RNA (gRNA) includes structural elements that regulate reverse transcription, transcription, translation, tRNALys3 annealing to the gRNA, and gRNA dimerization and packaging into viruses. It has been reported that gRNA dimerization and packaging are regulated by changes in the conformation of the 5′-UTR RNA. In this study, we show that annealing of tRNALys3 or a DNA oligomer complementary to sequences within the primer binding site (PBS) loop of the 5′ UTR enhances its dimerization in vitro. Structural analysis of the 5′-UTR RNA using selective 2′-hydroxyl acylation analyzed by primer extension (SHAPE) shows that the annealing promotes a conformational change of the 5′ UTR that has been previously reported to favor gRNA dimerization and packaging into virus. The model predicted by SHAPE analysis is supported by antisense experiments designed to test which annealed sequences will promote or inhibit gRNA dimerization. Based on reports showing that the gRNA dimerization favors its incorporation into viruses, we tested the ability of a mutant gRNA unable to anneal to tRNALys3 to be incorporated into virions. We found a ∼60% decrease in mutant gRNA packaging compared with wild-type gRNA. Together, these data further support a model for viral assembly in which the initial annealing of tRNALys3 to gRNA is cytoplasmic, which in turn aids in the promotion of gRNA dimerization and its incorporation into virions. PMID:23960173

  20. Assessing the conditions favorable for the occurrence of gas hydrate in the Tuonamu area Qiangtang basin, Qinghai–Tibetan, China

    International Nuclear Information System (INIS)

    He Jianglin; Wang Jian; Fu Xiugen; Zheng Chenggang; Chen Yanting

    2012-01-01

    Highlights: ► This is a pioneer research on the exploration of gas hydrate in Qiangtang basin. ► The factors influencing the stable of gas hydrate in Tuonamu area were studied. ► Simulation shows that gas hydrate stable zone is about 300 m thick in target area. ► Source condition is the key factor for the formation of gas hydrate in this area. ► The areas around the deeper faults are favorable targets for gas hydrate. - Abstract: Qiangtang basin, which is located in the largest continuous permafrost area in Qinghai–Tibetan Plateau, is expected to be a strategic area of gas hydrate exploitation in China. However, relatively little work has been done on the exploration of gas hydrate in this area. In this work, we evaluated the factors controlling the formation of gas hydrate in the Tuonamu area and provided a preliminary insight into gas hydrate distribution in it on the basis of the core samples, seismic data and laboratory analysis. It can be concluded that the source rock in the deeper formation would be dominant thermogenic source for the formation of gas hydrate in Tuonamu area. The thickness of gas hydrate stable zone in this area is about 300 m. The gas hydrate in the area most probably is in the form of gas-hydrate-water. The source condition is the key factor for the formation of gas hydrate and the gas hydrate layer would be mainly present in the form of interlayer in this area. The areas around the deeper faults are the favorable targets for the exploration of gas hydrate in the Tuonamu area.