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Sample records for asymmetric effects ofincreasing

  1. Why even active people get fatter--the asymmetric effects ofincreasing and decreasing exercise

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Paul T.

    2006-01-06

    Background: Public health policies for preventing obesityneed guidelines for active individuals who are at risk due to exerciserecidivism. Methods: Changes in adiposity were compared to the runningdistances at baseline and follow-up in men and women whose reportedexercise increased (N=4,632 and 1,953, respectively) or decreased (17,280and 5,970, respectively) during 7.7 years of follow-up. Results: PerDelta km/wk, decreases in running distance caused over four-fold greaterweight gain between 0-8 km/wk (slope+-SE, males: -0.068+ -0.005 kg/m2,females: -0.080+-0.01 kg/m2) than between 32-48 km/wk (-0.017+-0.002 and-0.010+-0.005 kg/m2, respectively). In contrast, increases in runningdistance produced the smallest weight losses between 0-8 km/wk andstatistically significant weight loss only above 16 km/wk in males and 32km/wk in females. Above 32 km/wk (30 kcal/kg) in men and 16 km/wk (15kcal/kg) in women, weight loss from increasing exercise was equal to orgreater than weight gained with decreasing exercise, otherwise weightgain exceeded weight loss. Substantial weight gain occurred in runnerswho quit running, which would be mostly retained with resumed activity.Conclusion: Public health recommendations should warn against the risksof irreversible weight gain with exercise cessation. Weight gained due toreductions in exercise below 30 kcal/kg in men and 15 kcal/kg in womenmay not be reversed by resuming prior activity. Current IOM guidelines(i.e., maintain total energy expenditure at 160 percent of basal) agreewith the men s exercise threshold for symmetric weight change withchanging exercise levels.

  2. Asymmetric Dark Matter and Effective Operators

    CERN Document Server

    Buckley, Matthew R

    2011-01-01

    In order to annihilate in the early Universe to levels well below the measured dark matter density, asymmetric dark matter must possess large couplings to the Standard Model. In this paper, we consider effective operators which allow asymmetric dark matter to annihilate into quarks. In addition to a bound from requiring sufficient annihilation, the energy scale of such operators can be constrained by limits from direct detection and monojet searches at colliders. We show that the allowed parameter space for these operators is highly constrained, leading to non-trivial requirements that any model of asymmetric dark matter must satisfy.

  3. δ Meson Effects on Asymmetric Nuclear Matter

    Science.gov (United States)

    Liu, B.; di Toro, M.; Greco, V.

    The impact of a δ meson field (the scalar-isovector channel) on asymmetric nuclear matter is studied within relativistic mean-field (RMF) models with both constant and density dependent (DD) nucleon-meson couplings. The Equation of State (EOS) for asymmetric nuclear matter and the neutron star properties by the different models are compared. We find that the δ-field in the constant coupling scheme leads to a larger repulsion in dense neutron-rich matter and to a definite splitting of proton and neutron effective masses, finally influencing the stability of the neutron stars. A broader analysis of possible δ-field effects is achieved considering also density dependent nucleon-meson coupling. A remarkable effect on the relation between mass and radius for the neutron stars is seen, showing a significant reduction of the radius along with a moderate mass reduction due to the increase of the effective δ coupling in high density regions.

  4. The Asymmetric Effects of Investor Sentiment

    DEFF Research Database (Denmark)

    Lutz, Chandler

    2016-01-01

    are asymmetric: During peak-to-trough periods of investor sentiment (sentiment contractions), high sentiment predicts low future returns for the cross section of speculative stocks and for the market overall, whereas the relationship between sentiment and future returns is positive but relatively weak during......We use the returns on lottery-like stocks and a dynamic factor model to construct a novel index of investor sentiment. This new measure is highly correlated with other behavioral indicators, but more closely tracks speculative episodes. Our main new finding is that the effects of sentiment...... trough-to-peak episodes (sentiment expansions). Overall, these results match theories and anecdotal accounts of investor sentiment....

  5. Asymmetric effects of monetary policy in Brazil

    Directory of Open Access Journals (Sweden)

    Edilean Kleber da Silva Bejarano Aragón

    2009-06-01

    Full Text Available In this paper, we check whether the effects of monetary policy actions on output in Brazil are asymmetric. Therefore, we estimate Markov-switching models that allow positive and negative shocks to affect the growth rate of output in an asymmetric fashion in expansion and recession states. In general, results show that: i the real effects of negative monetary shocks are larger than those of positive shocks in an expansion; ii in a recession, the real effects of positive and negative shocks are the same; iii there is no evidence of asymmetry between the effects of countercyclical monetary policies; and iv it is not possible to assert that the effects of a positive (or negative shock are dependent upon the phase of the business cycle.Neste trabalho, examinamos se os efeitos das ações de política monetária sobre o produto são assimétricos no Brasil. Para isto, estimamos modelos Markov-switching que permitem que choques positivos e negativos afetem a taxa de crescimento do produto de forma assimétrica nos estados de expansão e recessão econômica. Em geral, os resultados mostram que: i os efeitos reais de choques monetários negativos são maiores do que os de choques positivos em uma expansão; ii em uma recessão, os efeitos reais de choques positivos e negativos são iguais; iii não há evidência de assimetria entre os efeitos de políticas monetárias contracíclicas; iv não se pode afirmar que os efeitos de choques positivos (ou negativos dependem da fase do ciclo econômico.

  6. The Asymmetric Effects of Investor Sentiment

    DEFF Research Database (Denmark)

    Lutz, Chandler

    2016-01-01

    are asymmetric: During peak-to-trough periods of investor sentiment (sentiment contractions), high sentiment predicts low future returns for the cross section of speculative stocks and for the market overall, whereas the relationship between sentiment and future returns is positive but relatively weak during...... trough-to-peak episodes (sentiment expansions). Overall, these results match theories and anecdotal accounts of investor sentiment....

  7. The Asymmetric Effects of Investor Sentiment

    DEFF Research Database (Denmark)

    Lutz, Chandler

    We use the returns on lottery-like stocks to construct a novel index for investor sentiment in the stock market. This new measure is closely related to previously developed sentiment indicators, but more accurately tracks speculative episodes over the sample period. Using our index, we find...... that the relationship between sentiment and returns is asymmetric: during bear markets, high sentiment predicts low future returns for the cross-section of speculative stocks and the market overall while the relationship during bull markets is weak and often insignificant. Thus, the results suggest that sophisticated...... investors only act as corrective force during certain time periods. We also show that our index predicts implied volatility, media pessimism, and mutual fund flows. Overall, our findings are consistent with both the theories and anecdotal accounts of investor sentiment in the stock market....

  8. The Asymmetric Predictive Effects of Investor Sentiment

    DEFF Research Database (Denmark)

    Lutz, Chandler

    We use the returns on lottery-like stocks to construct a novel index for investor sentiment in the stock market. This new measure is closely related to previously developed sentiment indicators, but more accurately tracks speculative episodes over the sample period. Using our index, we find...... that the relationship between sentiment and returns is asymmetric: during bear markets, high sentiment predicts low future returns for the cross-section of speculative stocks and the market overall while the relationship during bull markets is weak and often insignicant. Thus, the results suggest that sophisticated...... investors only act as corrective force during certain time periods. We also show that our index predicts implied volatility, media pessimism, and mutual fund flows. Overall, our findings are consistent with both the theories and anecdotal accounts of investor sentiment in the stock market....

  9. Asymmetric inhibitory treatment effects in multilingual aphasia.

    Science.gov (United States)

    Goral, Mira; Naghibolhosseini, Maryam; Conner, Peggy S

    2013-01-01

    Findings from recent psycholinguistic studies of bilingual processing support the hypothesis that both languages of a bilingual are always active and that bilinguals continually engage in processes of language selection. This view aligns with the convergence hypothesis of bilingual language representation. Furthermore, it is hypothesized that when bilinguals perform a task in one language they need to inhibit their other, nontarget language(s) and that stronger inhibition is required when the task is performed in the weaker language than in the stronger one. The study of multilingual individuals who acquire aphasia resulting from a focal brain lesion offers a unique opportunity to test the convergence hypothesis and the inhibition asymmetry. We report on a trilingual person with chronic nonfluent aphasia who at the time of testing demonstrated greater impairment in her first acquired language (Persian) than in her third, later learned language (English). She received treatment in English followed by treatment in Persian. An examination of her connected language production revealed improvement in her grammatical skills in each language following intervention in that language, but decreased grammatical accuracy in English following treatment in Persian. The increased error rate was evident in structures that are used differently in the two languages (e.g., auxiliary verbs). The results support the prediction that greater inhibition is applied to the stronger language than to the weaker language, regardless of their age of acquisition. We interpret the findings as consistent with convergence theories that posit overlapping neuronal representation and simultaneous activation of multiple languages and with proficiency-dependent asymmetric inhibition in multilinguals.

  10. DAMA annual modulation effect and asymmetric mirror matter

    Energy Technology Data Exchange (ETDEWEB)

    Addazi, A.; Berezhiani, Z. [Universita di L' Aquila, Dipartimento di Scienze Fisiche e Chimiche, Coppito, AQ (Italy); INFN, Laboratori Nazionali del Gran Sasso, Assergi, AQ (Italy); Bernabei, R.; Belli, P. [Universita di Roma ' ' Tor Vergata' ' , Dipartimento di Fisica, Rome (Italy); INFN, Tor Vergata, Rome (Italy); Cappella, F.; Cerulli, R. [INFN, Laboratori Nazionali del Gran Sasso, Assergi, AQ (Italy); Incicchitti, A. [Universita di Roma ' ' La Sapienza' ' , Roma, Dipartimento di Fisica, Rome (Italy); INFN, Roma (Italy)

    2015-08-15

    The long-standing model-independent annual modulation effect measured by DAMA Collaboration is examined in the context of asymmetric mirror dark matter, assuming that dark atoms interact with target nuclei in the detector via kinetic mixing between mirror and ordinary photons, both being massless. The relevant ranges for the kinetic mixing parameter are obtained taking into account various existing uncertainties in nuclear and particle physics quantities as well as characteristic density and velocity distributions of dark matter in different halo models. (orig.)

  11. Pairing effects on spinodal decomposition of asymmetric nuclear matter

    Directory of Open Access Journals (Sweden)

    Burrello S.

    2015-01-01

    Full Text Available We present an analysis framed in the general context of two-component fermionic systems subjected to pairing correlations. The study is conducted for unstable asymmetric nuclear matter at low temperature, along the clusterization process driven by spinodal instabilities. It is shown that, especially around the transition temperature from the superfluid to the normal phase, pairing correlations may have non-negligible effects on the isotopic features of the clusterized low-density matter, which could be of interest also in the astrophysical context.

  12. Isovector Scalar Field Effects in Asymmetric Nuclear Matter

    Institute of Scientific and Technical Information of China (English)

    WANG Zhi-Xia; LIU Bo; ZHANG Xi-He; SHEN Cai-Wan; SHEN Ke; M. Di Toro; ZHAO En-Guang

    2008-01-01

    Density-dependent parametrization models of the nucleon-meson coupling constants, including the isovector scalar δ-field, are applied to asymmetric nuclear matter. The nuclear equation of state (EOS) and the neutron star properties are studied in a relativistic Lagrangian density, using the relativistic mean field (RMF) hadron theory. It is known that the 5-field in the constant coupling scheme leads to a larger repulsion in dense neutron-rich matter and to a definite splitting of proton and neutron effective masses, finally influences the stability of the neutron stars. We use density-dependent models of the nucleon-meson couplings to study the properties of neutron star matter and to reexamine the δ-field effects in asymmetric nuclear matter. Our calculation shows that the stability conditions of the neutron star matter can be improved in presence of the 5-meson in the density-dependent models of the coupling constants. The EOS of nuclear matter strongly depends on the density dependence of the interactions.

  13. Asymmetric effects of FOREX intervention using intraday data: evidence from Peru

    OpenAIRE

    Erick Lahura; Marco Vega

    2013-01-01

    Asymmetric effects of Central Bank foreign exchange (forex) intervention have not been extensively studied in the literature, even though in practice Central Bank's motives for purchasing and for selling foreign currency may differ. This paper studies asymmetric effects of Central Bank interventions under the premise that policy authorities view depreciations and appreciations as having asymmetric implications. Using undisclosed intraday data for Peru from 2009 to 2011, this paper shows that ...

  14. Effects of Noise on Asymmetric Bidirectional Controlled Teleportation

    Science.gov (United States)

    Nie, Yi-you; Sang, Ming-huang

    2016-07-01

    We present a scheme for asymmetric bidirectional controlled teleportation via a six-qubit cluster state in noisy environments, which includes the phase-damping and amplitude-damping channels. We analytically derive the fidelities of the asymmetric bidirectional controlled teleportation process in these two noise channels. We show that the fidelities only depend on the initial state and the noisy rate.

  15. Effect of Soil Structure Interaction on Torsional Response of Structure Supported by Asymmetric Soil Foundation System

    OpenAIRE

    Fangyuan Zhou; Xuezhang Wen; Hongping Zhu

    2016-01-01

    The torsional response of a structure supported by asymmetric foundation was investigated in this study. Several types of the asymmetric soil foundation system were employed to analyze the effect of soil structure interaction on torsional response of the superstructure. It can be concluded from the study that torsional response would be generated for a structure supported by asymmetric soil foundation system under horizontal seismic excitation, and the generated torsional response of the supe...

  16. Purcell effect of asymmetric dipole source distributions in nanowire resonators

    DEFF Research Database (Denmark)

    Filonenko, Konstantin; Duggen, Lars; Adam, Jost;

    of the asymmetric source distributions in proximity to the metal nanowire in two configurations: a metal cylinder truncated by the PEC plates and finite metal cylinder in free-space. In order to evaluate Purcell factor the mode eigenvalues are precalculated using Comsol Multiphysics radio frequency module. We...

  17. Purcell effect of asymmetric dipole source distributions in nanowire resonators

    DEFF Research Database (Denmark)

    Filonenko, Konstantin; Duggen, Lars; Adam, Jost;

    2015-01-01

    of the asymmetric source distributions in proximity to the metal nanowire in two configurations: a metal cylinder truncated by the PEC plates and finite metal cylinder in free-space. In order to evaluate Purcell factor the mode eigenvalues are precalculated using Comsol Multiphysics radio frequency module. We...

  18. Asymmetrically pumped Bragg scattering with the effects of nonlinear phase modulation

    DEFF Research Database (Denmark)

    Andersen, Lasse Mejling; Friis, Søren Michael Mørk; Reddy, Dileep V.;

    2014-01-01

    We derive exact solutions to asymmetrically pumped Bragg scattering with nonlinear phase-modulation (NPM) and show that this setup allows for the frequency conversion of many temporal modes, while reducing the effects due to NPM.......We derive exact solutions to asymmetrically pumped Bragg scattering with nonlinear phase-modulation (NPM) and show that this setup allows for the frequency conversion of many temporal modes, while reducing the effects due to NPM....

  19. Effect of Soil Structure Interaction on Torsional Response of Structure Supported by Asymmetric Soil Foundation System

    Directory of Open Access Journals (Sweden)

    Fangyuan Zhou

    2016-01-01

    Full Text Available The torsional response of a structure supported by asymmetric foundation was investigated in this study. Several types of the asymmetric soil foundation system were employed to analyze the effect of soil structure interaction on torsional response of the superstructure. It can be concluded from the study that torsional response would be generated for a structure supported by asymmetric soil foundation system under horizontal seismic excitation, and the generated torsional response of the superstructure changed with the degree of the asymmetry of the foundation.

  20. Comparing the Ratchet Effects of Cold Atoms in Periodically Symmetric and Asymmetric Optical Potentials

    Directory of Open Access Journals (Sweden)

    Nkongho Ayuketang Arreyndip

    2015-01-01

    Full Text Available We consider a particle in a spatial symmetric/asymmetric potential driven by time periodic bichromatic AC fields of ratchet type. The associated time-dependent Schrödinger equation is conveniently tackled with the Floquet theory. We next proceed to investigate the ratchet effect induced by the driver, comparing the symmetric with the asymmetric cases. It turns out that the current in the asymmetric case is stronger than that of the symmetric one. Besides, we also investigate the case where the driver is a delta kicked acting on our spatial potential with more emphasis on its chaotic behaviour. Here we check that the current emerges as the phase space is mixed and that the system with asymmetric spatial potential becomes more chaotic than the symmetric one at low kicking strength.

  1. Asymmetric acoustic propagation of wave packets via the self-demodulation effect

    CERN Document Server

    Devaux, Thibaut; Richoux, Olivier; Pagneux, Vincent

    2015-01-01

    This article presents the experimental characterization of nonreciprocal elastic wave transmission in a single-mode elastic waveguide. This asymmetric system is obtained by coupling a selection layer with a conversion layer: the selection component is provided by a phononic crystal, while the conversion is achieved by a nonlinear self-demodulation effect in a 3D unconsolidated granular medium. A quantitative experimental study of this acoustic rectifier indicates a high rectifying ratio, up to $10^6$, with wide band (10 kHz) and an audible effect. Moreover, this system allows for wave-packet rectification and extends the future applications of asymmetric systems.

  2. Experimental adiabatic vortex ratchet effect in Nb films with asymmetric pinning trap

    Indian Academy of Sciences (India)

    J E Villegas; N O nunez; M P Gonzalez; E M Gonalez; J L Vicent

    2006-01-01

    Nb films grown on top of an array of asymmetric pinning centers show a vortex ratchet effect. A net flow of vortices is induced when the vortex lattice is driven by fluctuating forces on an array of pinning centers without reflection symmetry. This effect occurs in the adiabatic regime and it could be mimiced only by reversible DC driven forces.

  3. Effects of gravitational confinement on bosonic asymmetric dark matter in stars

    CERN Document Server

    Jamison, Alan O

    2013-01-01

    Considering the existence of old neutron stars puts strong limits on the dark matter/nucleon cross section for bosonic asymmetric dark matter. Key to these bounds is formation of a Bose-Einstein condensate (BEC) of the asymmetric dark matter particles. We consider the effects of the host neutron star's gravitational field on the BEC transition. We find this substantially shifts the transition temperature and so strengthens the bounds on cross section. In particular, for the well-motivated mass range of ~5-15 GeV, we improve previous bounds by an order of magnitude.

  4. Intrinsic potential of cell membranes: opposite effects of lipid transmembrane asymmetry and asymmetric salt ion distribution

    DEFF Research Database (Denmark)

    Gurtovenko, Andrey A; Vattulainen, Ilpo

    2009-01-01

    Using atomic-scale molecular dynamics simulations, we consider the intrinsic cell membrane potential that is found to originate from a subtle interplay between lipid transmembrane asymmetry and the asymmetric distribution of monovalent salt ions on the two sides of the cell membrane. It turns out......Cl saline solution and the PE leaflet is exposed to KCl, the outcome is that the effects of asymmetric lipid and salt ion distributions essentially cancel one another almost completely. Overall, our study highlights the complex nature of the intrinsic potential of cell membranes under physiological...

  5. Slip and heat transfer effects on peristaltic motion of a Carreau fluid in an asymmetric channel

    Energy Technology Data Exchange (ETDEWEB)

    Hayat, Tasawar [Quaid-i-Azam Univ., Islamabad (Pakistan). Dept. of Mathematics; King Saud Univ., Riyadh (Saudi Arabia). Dept. of Mathematics; Saleem, Najma [Quaid-i-Azam Univ., Islamabad (Pakistan). Dept. of Mathematics; Hendi, Awatif A. [Dept. of Physics, Riyadh (Saudi Arabia). Faculty of Science

    2010-12-15

    An analysis has been carried out for peristaltic flow and heat transfer of a Carreau fluid in an asymmetric channel with slip effect. The governing problem is solved under long wavelength approximation. The variations of pertinent dimensionless parameters on temperature are discussed. Pumping and trapping phenomena are studied. (orig.)

  6. Ambipolar Tetraphenylpyrene (TPPy) Single-Crystal Field-Effect Transistor with Symmetric and Asymmetric Electrodes

    NARCIS (Netherlands)

    Bisri, S Z; Takahashi, T; Takenobu, T; Yahiro, M; Adachi, C; Iwasa, Y

    2008-01-01

    An ambipolar field-effect transistor (FET) based on a 1,3,6, 8-tetraphenylpyrene (TPPy) single-crystal, a high photoluminescent material, has been successfully fabricated using symmetric and asymmetric electrodes. Several kinds of metal electrodes have been employed to investigate the charge injecti

  7. Asymmetric Effect of Monetary Policy on Stock Market Volatility in ASEAN5

    OpenAIRE

    Trung Thanh BUI

    2015-01-01

    Among many channels, stock market directly transmits the effect of monetary policy decisions because it quickly responds to policy news. The primary objective of this paper is to clarify the asymmetric effect of monetary policy on stock market volatility, which is believed to have adverse effects on the economy recovery, over its bull and bear period. We performed empirical research in a panel setting in which monthly data of ASEAN5 (Vietnam, Thailand, Philippines, Malaysia, an...

  8. The effect of transverse crack upon parametric instability of a rotor-bearing system with an asymmetric disk

    Science.gov (United States)

    Han, Qinkai; Chu, Fulei

    2012-12-01

    It is well known that either the asymmetric disk or transverse crack brings parametric inertia (or stiffness) excitation to the rotor-bearing system. When both of them appear in a rotor system, the parametric instability behaviors have not gained sufficient attentions. Thus, the effect of transverse crack upon parametric instability of a rotor-bearing system with an asymmetric disk is studied. First, the finite element equations of motion are established for the asymmetric rotor system. Both the open and breathing transverse cracks are taken into account in the model. Then, the discrete state transition matrix (DSTM) method is introduced for numerically acquiring the instability regions. Based upon these, some computations for a practical asymmetric rotor system with open or breathing transverse crack are conducted, respectively. Variations of the primary and combination instability regions induced by the asymmetric disk with the crack depth are observed, and the effect of the orientation angle between the crack and asymmetric disk on various instability regions are discussed in detail. It is shown that for the asymmetric angle around 0, the existence of transverse (either open or breathing) crack has attenuation effect upon the instability regions. Under certain crack depth, the instability regions could be vanished by the transverse crack. When the asymmetric angle is around π/2, increasing the crack depth would enhance the instability regions.

  9. Taking a deeper look at online reviews: The asymmetric effect of valence intensity on shopping behaviour

    OpenAIRE

    Floh, A.; Koller, Monika; Zauner, Alexander

    2013-01-01

    This study tests the asymmetric effect of user-generated, open-ended online reviews on online shopping behaviour (intention-to-buy, intention-to-recommend, and willingness-to-pay). Three online experiments involving manipulating the valence intensity of online reviews for hotels, books, and running shoes (overall customer sample of n=818) provide empirical support for the proposed relationship. The valence intensity of online reviews moderates the effect of online reviews on purchase intentio...

  10. Asymmetric effects of luminance and chrominance in the watercolor illusion

    Directory of Open Access Journals (Sweden)

    Andrew eCoia

    2014-09-01

    Full Text Available When bounded by a line of sufficient contrast, the desaturated hue of a colored line will spread over an enclosed area, an effect known as the watercolor illusion. The contrast of the two lines can be in luminance, chromaticity, or a combination of both. The effect is most salient when the enclosing line has greater contrast with the background than the line that induces the spreading color. In most prior experiments with watercolor spreading, the luminance of both lines has been lower than the background. An achromatic version of the illusion exists where a dark line will spread while being bounded by either a darker or brighter line. In a previous study we measured the strength of the watercolor effect in which the colored inducing line was isoluminant to the background, and found an illusion for both brighter and darker achromatic outer contours. We also found the strength of spreading is stronger for bluish (+S cone input colors compared to yellowish (-S cone input ones, when bounded by a dark line. The current study set out to measure the hue dependence of the watercolor illusion when inducing colors are flanked with brighter (increment as opposed to darker outer lines. The asymmetry in the watercolor effect with S cone input was enhanced when the inducing contrast was an increment rather than a decrement. Further experiments explored the relationship between the perceived contrast of these chromatic lines when paired with luminance increments and decrements and revealed that the perceived contrast of luminance increments and decrements is dependent on which isoluminant color they are paired with. In addition to known hue asymmetries in the watercolor illusion there are asymmetries between luminance increments and decrements that are also hue dependent. These latter asymmetries may be related to the perceived contrast of the hue/luminance parings.

  11. Chiral magnetic effect without chirality source in asymmetric Weyl semimetals

    CERN Document Server

    Kharzeev, Dmitri; Meyer, Rene

    2016-01-01

    We describe a new type of the Chiral Magnetic Effect (CME) that should occur in Weyl semimetals with an asymmetry in the dispersion relations of the left- and right-handed chiral Weyl fermions. In such materials, time-dependent pumping of electrons from a non-chiral external source generates a non-vanishing chiral chemical potential. This is due to the different capacities of the left- and right-handed (LH and RH) chiral Weyl cones arising from the difference in the density of states in the LH and RH cones. The chiral chemical potential then generates, via the chiral anomaly, a current along the direction of an applied magnetic field even in the absence of an external electric field. The source of chirality imbalance in this new setup is thus due to the band structure of the system and the presence of (non-chiral) electron source, and not due to the parallel electric and magnetic fields. We illustrate the effect by an argument based on the effective field theory, and by the chiral kinetic theory calculation f...

  12. Effect of induced magnetic field on peristaltic flow of a micropolar fluid in an asymmetric channel

    OpenAIRE

    Shit, G. C.; Roy, M.; E. Y. K. Ng

    2010-01-01

    Of concern in this paper is an investigation of peristaltic transport of a physiological fluid in an asymmetric channel under long wave length and low-Reynolds number assumptions. The flow is assumed to be incompressible, viscous, electrically conducting micropolar fluid and the effect of induced magnetic field is taken into account. Exact analytical solutions obtained for the axial velocity, microrotation component, stream line pattern, magnetic force function, axial-induced magnetic field a...

  13. The Effects Of Asymmetric Transmission Of Exchange Rate On Inflation In Iran: Application Of Threshold Models

    Directory of Open Access Journals (Sweden)

    Naghdi Yazdan

    2015-08-01

    Full Text Available Given the recent fluctuation in the exchange rate and the presence of several factors such as the various economy-political sanctions (mainly embargos on oil and banking, extreme volatility in different economic fields, and consequently the devaluation of national and public procurement -A landmark that is emanating from exchange rate fluctuation - two points should be noted: First, it is essential to review the effect of exchange rate fluctuation on macro economic variables such as inflation and to provide appropriate policies. Second, the existence of this condition provides the chance to study the relation between exchange rate and inflation in a non-linear and asymmetric method. Hence, the present study seeks to use TAR model and, on the basis of monthly time series data over the period March 2002 to March 2014, to analyze the cross-asymmetric and non-linear exchange rate on consumer price index (CPI in Iran. The results also show the presence of an asymmetric long-term relationship between these variables (exchange rate and CPI. Also, in the Iranian economy, the effect of negative shocks of exchange rate on inflation is more sustainable than the one from positive shocks.

  14. Effects of dimethyl sulfoxide on asymmetric division and cytokinesis in mouse oocytes

    Institute of Scientific and Technical Information of China (English)

    Shen Xinghui; Zhou Dongjie; Gu Yanli; Zhang Na; Li Tong; Wu Xi; Lei Lei

    2015-01-01

    Objective: To observe the effect of DMSO on mouse oocyte meiotic maturation. Results: In DMSO-treated oocytes, we observed abnormal MII oocytes that contained large polar bodies, including 2-cell-like MII oocytes, during in vitro maturation. Oocyte polarization did not occur, due to the absence of actin cap forma-tion and spindle migration. These features are among the primary causes of abnormal symmetric division;however, analysis of the mRNA expression levels of genes related to asymmetric division revealed no significant difference in the expression of these factors between the 3% DMSO-treated group and the control group. After each "blasto-mere" of the 2-cell-like MII stage oocytes was injected by one sperm head respectively, the oocytes still possessed the ability to extrude the second polar body from each "blastomere" and to begin cleavage. However, MII oocytes with large polar bodies developed to the blastocyst stage after intracytoplasmic sperm injection ( ICSI ) . Further-more, other permeable cryoprotectants, such as ethylene glycol and glycerol, also caused asymmetric division fail-ure. Conclusions:Permeable cryoprotectants, such as DMSO, ethylene glycol, and glycerol, affect asymmetric di-vision. DMSO disrupts cytokinesis completion by inhibiting cortical reorganization and polarization. Oocytes that undergo symmetric division maintain the ability to begin cleavage after ICSI.

  15. Coupled effects of market impact and asymmetric sensitivity in financial markets

    Science.gov (United States)

    Zhong, Li-Xin; Xu, Wen-Juan; Ren, Fei; Shi, Yong-Dong

    2013-05-01

    By incorporating market impact and asymmetric sensitivity into the evolutionary minority game, we study the coevolutionary dynamics of stock prices and investment strategies in financial markets. Both the stock price movement and the investors’ global behavior are found to be closely related to the phase region they fall into. Within the region where the market impact is small, investors’ asymmetric response to gains and losses leads to the occurrence of herd behavior, when all the investors are prone to behave similarly in an extreme way and large price fluctuations occur. A linear relation between the standard deviation of stock price changes and the mean value of strategies is found. With full market impact, the investors tend to self-segregate into opposing groups and the introduction of asymmetric sensitivity leads to the disappearance of dominant strategies. Compared with the situations in the stock market with little market impact, the stock price fluctuations are suppressed and an efficient market occurs. Theoretical analyses indicate that the mechanism of phase transition from clustering to self-segregation in the present model is similar to that in the majority-minority game and the occurrence and disappearance of efficient markets are related to the competition between the trend-following and the trend-aversion forces. The clustering of the strategies in the present model results from the majority-wins effect and the wealth-driven mechanism makes the market become predictable.

  16. The effect of symmetrical and asymmetrical hearing impairment on music quality perception.

    Science.gov (United States)

    Cai, Yuexin; Zhao, Fei; Chen, Yuebo; Liang, Maojin; Chen, Ling; Yang, Haidi; Xiong, Hao; Zhang, Xueyuan; Zheng, Yiqing

    2016-09-01

    The purpose of this study was to investigate the effect of symmetrical, asymmetrical and unilateral hearing impairment on music quality perception. Six validated music pieces in the categories of classical music, folk music and pop music were used to assess music quality in terms of its 'pleasantness', 'naturalness', 'fullness', 'roughness' and 'sharpness'. 58 participants with sensorineural hearing loss [20 with unilateral hearing loss (UHL), 20 with bilateral symmetrical hearing loss (BSHL) and 18 with bilateral asymmetrical hearing loss (BAHL)] and 29 normal hearing (NH) subjects participated in the present study. Hearing impaired (HI) participants had greater difficulty in overall music quality perception than NH participants. Participants with BSHL rated music pleasantness and naturalness to be higher than participants with BAHL. Moreover, the hearing thresholds of the better ears from BSHL and BAHL participants as well as the hearing thresholds of the worse ears from BSHL participants were negatively correlated to the pleasantness and naturalness perception. HI participants rated the familiar music pieces higher than unfamiliar music pieces in the three music categories. Music quality perception in participants with hearing impairment appeared to be affected by symmetry of hearing loss, degree of hearing loss and music familiarity when they were assessed using the music quality rating test (MQRT). This indicates that binaural symmetrical hearing is important to achieve a high level of music quality perception in HI listeners. This emphasizes the importance of provision of bilateral hearing assistive devices for people with asymmetrical hearing impairment. PMID:26611684

  17. Dual-Material Surrounding-Gate Metal-Oxide-Semiconductor Field Effect Transistors with Asymmetric Halo

    Institute of Scientific and Technical Information of China (English)

    LI Zun-Chao

    2009-01-01

    Asymmetrical halo and dual-material gate structure are used in the sub-100 nm surrounding-gate metal-oxide-semiconductor field effect transistor (MOSFET) to improve the performance. Using three-region parabolic po-tential distribution and universal boundary condition, analytical surface potential and threshold voltage models of the novel MOSFET are developed based on the solution of Poisson's equation. The performance of the MOS-FET is examined by the analytical models and the 3D numerical device simulator Davinci. It is shown that the novel MOSFET can suppress short channel effect and improve carrier transport efficiency. The derived analytical models agree well with Davinci.

  18. Cherenkov and Fano effects at the origin of asymmetric vector mesons in nuclear media

    CERN Document Server

    Dremin, I M

    2015-01-01

    It is argued that the experimentally observed phenomenon of asymmetric vector mesons produced in nuclear media during high energy nucleus-nucleus collisions can be explained as Cherenkov and Fano effects. The mass distributions of lepton pairs created at meson decays decline from the traditional Breit-Wigner shape in the low-mass wing of the resonance. That is explained by the positive real part of the amplitude in this wing for classic Cherenkov treatment and further detalized in quantum mechanics as the interference of direct and continuum states in Fano effect. The corresponding parameters are found from the comparison with rho-meson data and admit reasonable explanation.

  19. Graphene field effect transistors with niobium contacts and asymmetric transfer characteristics.

    Science.gov (United States)

    Bartolomeo, Antonio Di; Giubileo, Filippo; Romeo, Francesco; Sabatino, Paolo; Carapella, Giovanni; Iemmo, Laura; Schroeder, Thomas; Lupina, Grzegorz

    2015-11-27

    We fabricate back-gated field effect transistors using niobium electrodes on mechanically exfoliated monolayer graphene and perform electrical characterization in the pressure range from atmospheric down to 10(-4) mbar. We study the effect of room temperature vacuum degassing and report asymmetric transfer characteristics with a resistance plateau in the n-branch. We show that weakly chemisorbed Nb acts as p-dopant on graphene and explain the transistor characteristics by Nb/graphene interaction with unpinned Fermi level at the interface. PMID:26535591

  20. Dual task effects for asymmetric stepping on a split-belt treadmill.

    NARCIS (Netherlands)

    McFadyen, B.J.; Hegeman, J.; Duysens, J.E.J.

    2009-01-01

    Bilaterally asymmetric stepping during walking is common to a number of pathological gaits (e.g., hemiplegia, limping). In the present work, the attention level of asymmetric stepping was studied by having subjects walk on a split-belt treadmill with symmetric (2 km/h) and asymmetric (2 km/h vs 4 km

  1. Field amplification, vortex formation, and electron acceleration in a plasma protoshock: effect of asymmetric density profile

    CERN Document Server

    Murphy, Gareth C; Drury, Luke O'C

    2011-01-01

    Gamma ray bursts (GRBs) are thought to originate from highly relativistic jets. The fireball model predicts internal shocks in the jets, causing magnetic field to be amplified and particles to be accelerated. We model the effects of an asymmetric density configuration for an internal plasma collision in a quasi-parallel magnetic field. We measured electron acceleration and found that a tenuous population of electrons is accelerated to Lorentz factors of \\sim 300 - close to energy equipartition with ions. We found that the filaments did not remain static, but were deflected by the Lorentz force and rolled up into small vortices, which themselves merge to form a larger current vortex.

  2. Strong Asymmetric Coupling of Two Parallel Exclusion Processes: Effect of Unequal Injection Rates

    Science.gov (United States)

    Xiao, Song; Dong, Peng; Zhang, Yingjie; Liu, Yanna

    2016-03-01

    In this letter, strong asymmetric coupling of two parallel exclusion processes: effect of unequal injection rates will be investigated. It is a generalization of the work of Xiao et al. (Phys. Lett. A 8, 374 (2009)), in which the particles only move on two lanes with rate 1 toward right. We can obtain the diverse phase diagram and density profiles of the system. The vertical cluster mean-field approach and extensively Monte Carlo simulations are used to study the system, and theoretical predictions are in excellent agreement with simulation results.

  3. The asymmetric effects of oil price and monetary policy shocks. A nonlinear VAR approach

    Energy Technology Data Exchange (ETDEWEB)

    Rahman, Sajjadur [Department of Economics, University of Saskatchewan, Saskatoon (Canada); Serletis, Apostolos [Department of Economics, University of Calgary, Calgary (Canada)

    2010-11-15

    In this paper we investigate the asymmetric effects of oil price shocks and monetary policy on macroeconomic activity, using monthly data for the United States, over the period from 1983:1 to 2008:12. In doing so, we use a logistic smooth transition vector autoregression (VAR), as detailed in Terasvirta and Anderson (1992) and Weise (1999), and make a distinction between two oil price volatility regimes (high and low), using the realized oil price volatility as a switching variable. We isolate the effects of oil price and monetary policy shocks and their asymmetry on output growth and, following Koop et al. (1996) and Weise (1999), we employ simulation methods to calculate Generalized Impulse Response Functions (GIRFs) to trace the effects of independent shocks on the conditional means of the variables. Our results suggest that in addition to the price of oil, oil price volatility has an impact on macroeconomic activity and that monetary policy is not only reinforcing the effects of oil price shocks on output, it is also contributing to the asymmetric response of output to oil price shocks. (author)

  4. The effects of intense laser field and applied electric and magnetic fields on optical properties of an asymmetric quantum well

    Energy Technology Data Exchange (ETDEWEB)

    Restrepo, R.L., E-mail: pfrire@eia.edu.co [Department of Physics, Cumhuriyet University, 58140 Sivas (Turkey); Escuela de Ingeniería de Antioquia-EIA, Envigado (Colombia); Grupo de Materia Condensada-UdeA, Instituto de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia-UdeA, Calle 70 No. 52-21, Medellín (Colombia); Ungan, F.; Kasapoglu, E. [Department of Physics, Cumhuriyet University, 58140 Sivas (Turkey); Mora-Ramos, M.E. [Facultad de Ciencias, Universidad Autonóma del Estado de Morelos, Ave. Universidad 1001, CP 62209, Cuernavaca, Morelos (Mexico); Morales, A.L.; Duque, C.A. [Grupo de Materia Condensada-UdeA, Instituto de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia-UdeA, Calle 70 No. 52-21, Medellín (Colombia)

    2015-01-15

    This paper presents the results of the theoretical study of the effects of non-resonant intense laser field and electric and magnetic fields on the optical properties (the linear and third-order nonlinear refractive index and absorption coefficients) in an asymmetric quantum well. The electric field and intense laser field are applied along the growth direction of the asymmetric quantum well and the magnetic field is oriented perpendicularly. To calculate the energy and the wave functions of the electron in the asymmetric quantum well, the effective mass approximation and the method of envelope wave function are used. The asymmetric quantum well is constructed by using different aluminium concentrations in both right and left barriers. The confinement in the quantum well is changed drastically by either the effect of electric and magnetic fields or by the application of intense laser field. The optical properties are calculated using the compact density matrix approach. The results show that the effect of the intense laser field competes with the effects of the electric and magnetic fields. Consequently, peak position shifts to lower photon energies due to the effect of the intense laser field and it shifts to higher photon energies by the effects of electric and magnetic fields. In general, it is found that the concentration of aluminum, electric and magnetic fields and intense laser field are external agents that modify the optical responses in the asymmetric quantum well.

  5. Postural effects of symmetrical and asymmetrical loads on the spines of schoolchildren

    Directory of Open Access Journals (Sweden)

    Negrini Stefano

    2007-07-01

    Full Text Available Abstract The school backpack constitutes a daily load for schoolchildren: we set out to analyse the postural effects of this load, considering trunk rotation, shoulder asymmetry, thoracic kyphosis, lumbar lordosis, and sagittal and frontal decompensation from the plumbline. A group of 43 subjects (mean age = 12.5 ± 0.5 years were considered: average backpack loads and average time spent getting to/from home/school (7 min had been determined in a previous study conducted on this population. Children were evaluated by means of an optoelectronic device in different conditions corresponding to their usual everyday school backpack activities: without load; bearing 12 (week maximum and 8 (week average kg symmetrical loads; bearing an 8 kg asymmetrical load; after fatigue due to backpack carrying (a 7-minute treadmill walking session bearing an 8 kg symmetrical load. Both types of load induce changes in posture: the symmetrical one in the sagittal plane, without statistical significant differences between 8 and 12 kg, and the asymmetrical one in all anatomical planes. Usual fatigue accentuates sagittal effects, but recovery of all parameters (except lumbar lordosis follows removal of the load. The backpack load effect on schoolchildren posture should be more carefully evaluated in the future, even if we must bear in mind that laws protect workers to carry heavy loads but not children, and results in the literature support the hypothesis that back pain in youngsters is correlated with back pain in adulthood

  6. Postural effects of symmetrical and asymmetrical loads on the spines of schoolchildren.

    Science.gov (United States)

    Negrini, Stefano; Negrini, Alberto

    2007-01-01

    The school backpack constitutes a daily load for schoolchildren: we set out to analyse the postural effects of this load, considering trunk rotation, shoulder asymmetry, thoracic kyphosis, lumbar lordosis, and sagittal and frontal decompensation from the plumbline. A group of 43 subjects (mean age = 12.5 +/- 0.5 years) were considered: average backpack loads and average time spent getting to/from home/school (7 min) had been determined in a previous study conducted on this population. Children were evaluated by means of an optoelectronic device in different conditions corresponding to their usual everyday school backpack activities: without load; bearing 12 (week maximum) and 8 (week average) kg symmetrical loads; bearing an 8 kg asymmetrical load; after fatigue due to backpack carrying (a 7-minute treadmill walking session bearing an 8 kg symmetrical load). Both types of load induce changes in posture: the symmetrical one in the sagittal plane, without statistical significant differences between 8 and 12 kg, and the asymmetrical one in all anatomical planes. Usual fatigue accentuates sagittal effects, but recovery of all parameters (except lumbar lordosis) follows removal of the load. The backpack load effect on schoolchildren posture should be more carefully evaluated in the future, even if we must bear in mind that laws protect workers to carry heavy loads but not children, and results in the literature support the hypothesis that back pain in youngsters is correlated with back pain in adulthood. PMID:17620121

  7. Founder effects and the evolution of asymmetrical sexual isolation in a rapidly-speciating clade

    Institute of Scientific and Technical Information of China (English)

    Kevin P.OH; Gina L.CONTE; Kerry L.SHAW

    2013-01-01

    Sexual isolation resulting from differences in mate choice behaviors is a hallmark of rapidly-speciating lineages.When present,asymmetrical sexual isolation may provide insights into the mechanisms responsible for the evolutionary change in mate signaling traits.In particular,Kaneshiro's hypothesis suggests that divergence in sexual characters between populations may arise in allopatry when ‘derived’ founding populations are subject to severe population bottlenecks,accompanied by a relaxation of sexual selection relative to ‘ancestral’ source populations.In the present study,we tested predictions of asymmetrical sexual isolation between two allopatric species of Hawaiian Laupala crickets,representing ‘ancestral’ (L.makaio) and ‘derived’ (L.nigra)taxa.While crickets in this genus are notable for rapid divergence of male courtship songs,these species share similar song types,thus suggesting that pattems of sexual isolation are likely due to other mating cues.Analysis of behavioral responses in conspecific and heterospecific ‘no-choice’ mating trials revealed pronounced asymmetrical isolation in the direction predicted by Kaneshiro's hypothesis,wherein we observed a significant reduction in mating success for crosses involving ‘derived’ males paired with ‘ancestral’ females,compared to the reciprocal heterospecific and both conspecific pairings.Further dissection of courtship behaviors suggested this difference did not reflect male mate choice,but rather,marked reduced spermatophore acceptance rates by ‘ancestral’ females paired with ‘derived’ males.The results are discussed with respect to founder effect models of speciation and the potential role of chemosensory signals in mate choice in these species.

  8. Asymmetric effects of daytime and night-time warming on Northern Hemisphere vegetation.

    Science.gov (United States)

    Peng, Shushi; Piao, Shilong; Ciais, Philippe; Myneni, Ranga B; Chen, Anping; Chevallier, Frédéric; Dolman, Albertus J; Janssens, Ivan A; Peñuelas, Josep; Zhang, Gengxin; Vicca, Sara; Wan, Shiqiang; Wang, Shiping; Zeng, Hui

    2013-09-01

    Temperature data over the past five decades show faster warming of the global land surface during the night than during the day. This asymmetric warming is expected to affect carbon assimilation and consumption in plants, because photosynthesis in most plants occurs during daytime and is more sensitive to the maximum daily temperature, Tmax, whereas plant respiration occurs throughout the day and is therefore influenced by both Tmax and the minimum daily temperature, Tmin. Most studies of the response of terrestrial ecosystems to climate warming, however, ignore this asymmetric forcing effect on vegetation growth and carbon dioxide (CO2) fluxes. Here we analyse the interannual covariations of the satellite-derived normalized difference vegetation index (NDVI, an indicator of vegetation greenness) with Tmax and Tmin over the Northern Hemisphere. After removing the correlation between Tmax and Tmin, we find that the partial correlation between Tmax and NDVI is positive in most wet and cool ecosystems over boreal regions, but negative in dry temperate regions. In contrast, the partial correlation between Tmin and NDVI is negative in boreal regions, and exhibits a more complex behaviour in dry temperate regions. We detect similar patterns in terrestrial net CO2 exchange maps obtained from a global atmospheric inversion model. Additional analysis of the long-term atmospheric CO2 concentration record of the station Point Barrow in Alaska suggests that the peak-to-peak amplitude of CO2 increased by 23 ± 11% for a +1 °C anomaly in Tmax from May to September over lands north of 51° N, but decreased by 28 ± 14% for a +1 °C anomaly in Tmin. These lines of evidence suggest that asymmetric diurnal warming, a process that is currently not taken into account in many global carbon cycle models, leads to a divergent response of Northern Hemisphere vegetation growth and carbon sequestration to rising temperatures.

  9. Effect of breathing pattern on gas mixing in a model with asymmetrical alveolar ducts.

    Science.gov (United States)

    Bowes, C L; Richardson, J D; Cumming, G; Horsfield, K

    1985-01-01

    A model of the pulmonary airways was used to study three single-breath indices of gas mixing, dead space (VD), slope of the alveolar plateau, and alveolar mixing inefficiency (AMI). In the model, discrete elements of airway volume were represented by nodes. Using a finite difference technique the differential equation for simultaneous convection and diffusion was solved for the nodal network. Conducting airways and respiratory bronchioles were modeled symmetrically, but alveolar ducts asymmetrically, permitting interaction between convection and diffusion. VD, alveolar slope, and AMI increased with increasing flow. Similar trends were seen with inspired volume, although slope decreased at high inspired volumes with constant flow. VD was affected most by inspiratory flow and AMI and alveolar slope by expiratory time. VD fell approximately exponentially with time of breath holding. Eight different breathing patterns were compared. They had a small effect on alveolar slope and AMI and a greater effect on VD. The model shows how series and parallel inhomogeneity occur together and interact in asymmetrical systems: the old argument as to which is the more important should be abandoned. PMID:3968008

  10. Effect of residual attractive interactions in size asymmetric colloidal mixtures: Theoretical analysis and predictions.

    Science.gov (United States)

    Germain, Ph

    2010-07-28

    We analyze the influence of residual attractions on the static and some dynamic properties of size asymmetric mixtures of "hard-sphere-like" colloids. These attractions, usually neglected in the theoretical analysis, are characterized by a very short range and a moderate strength reflecting the underlying microscopic structure of the colloidal particles. Their effect on the potentials of mean force is analyzed from analytical expressions obtained from low density expansions. The effective potential of the big particle fluid is next considered. An analytical expression is proposed for estimating the deviation with respect to the hard sphere depletion potential. This case is compared to that of mixtures with noninteracting depletants. The important consequences on the binodals and the glass transition lines of the effective fluid are discussed in both cases. This study is next extended to other properties-the specific heat and the low shear viscosity-which incorporate contributions from the two components of the binary mixture. PMID:20687684

  11. Effect of residual attractive interactions in size asymmetric colloidal mixtures: Theoretical analysis and predictions

    Science.gov (United States)

    Germain, Ph.

    2010-07-01

    We analyze the influence of residual attractions on the static and some dynamic properties of size asymmetric mixtures of "hard-sphere-like" colloids. These attractions, usually neglected in the theoretical analysis, are characterized by a very short range and a moderate strength reflecting the underlying microscopic structure of the colloidal particles. Their effect on the potentials of mean force is analyzed from analytical expressions obtained from low density expansions. The effective potential of the big particle fluid is next considered. An analytical expression is proposed for estimating the deviation with respect to the hard sphere depletion potential. This case is compared to that of mixtures with noninteracting depletants. The important consequences on the binodals and the glass transition lines of the effective fluid are discussed in both cases. This study is next extended to other properties—the specific heat and the low shear viscosity—which incorporate contributions from the two components of the binary mixture.

  12. Asymmetric Gate(AG)MOS Device:A Novel Field Effect Transistor(FET) Structure

    Institute of Scientific and Technical Information of China (English)

    YANGShengqi; HEJin; HUANGRu; ZHANGXing

    2003-01-01

    A novel fleld effect transistor(FET),named asymmetric gate(AG)MOS device,is proposed in this paper and its excellent performance is demonstrated numericall.Compared with the conventional MOSFET,the presented AG one benefits more from the special design of gate oxide which is divided into two regions,with one region at the source side thicker than that at the drain side.Two-dimensional (2-D)numerical simulations have proved that the short-channel effects(SCE)and the draininduced barrier lowering(DIBL)can be greatly suppressed just because the channel is screened from the drain potential variations via the unique gate oxide design.Also,a significant electron velocity overshoot is achieved,resulting in higher driving current in the novel structure.It shows that the AG structure will be one of the promising structures in design of MOS devices.

  13. The effect of the formyl group position upon asymmetric isomeric diarylethenes bearing a naphthalene moiety

    Directory of Open Access Journals (Sweden)

    Renjie Wang

    2012-07-01

    Full Text Available Three new isomeric asymmetric diarylethenes with a naphthyl moiety and a formyl group at the para, meta or ortho position of the terminal benzene ring were synthesized. Their photochromism, fluorescent-switch, and electrochemical properties were investigated. Among these diarylethenes, the one with a formyl group at the ortho position of benzene displayed the largest molar absorption coefficients and fluorescence quantum yield. The cyclization quantum yields of these compounds increased in the order of para para > ortho. Additionally, all of these diarylethenes functioned as effective fluorescent switches in both solution and PMMA films. Cyclic voltammograms proved that the formyl group and its position could effectively modulate the electrochemical behaviors of these diarylethene derivatives.

  14. Magnetic Field and Gravity Effects on Peristaltic Transport of a Jeffrey Fluid in an Asymmetric Channel

    Directory of Open Access Journals (Sweden)

    A. M. Abd-Alla

    2014-01-01

    Full Text Available In this paper, the peristaltic flow of a Jeffrey fluid in an asymmetric channel has been investigated. Mathematical modeling is carried out by utilizing long wavelength and low Reynolds number assumptions. Closed form expressions for the pressure gradient, pressure rise, stream function, axial velocity, and shear stress on the channel walls have been computed numerically. Effects of the Hartmann number, the ratio of relaxation to retardation times, time-mean flow, the phase angle and the gravity field on the pressure gradient, pressure rise, streamline, axial velocity, and shear stress are discussed in detail and shown graphically. The results indicate that the effect of Hartmann number, ratio of relaxation to retardation times, time-mean flow, phase angle, and gravity field are very pronounced in the peristaltic transport phenomena. Comparison was made with the results obtained in the presence and absence of magnetic field and gravity field.

  15. The modulation effect for supersymmetric dark matter detection with asymmetric velocity dispersion

    CERN Document Server

    Vergados, J D

    2000-01-01

    The detection of the theoretically expected dark matter is central to particle physics cosmology. Current fashionable supersymmetric models provide a natural dark matter candidate which is the lightest supersymmetric particle (LSP). Such models combined with fairly well understood physics like the quark substructure of the nucleon and the nuclear form factor and the spin response function of the nucleus, permit the evaluation of the event rate for LSP-nucleus elastic scattering. The thus obtained event rates are, however, very low or even undetectable. So it is imperative to exploit the modulation effect, i.e. the dependence of the event rate on the earth's annual motion. In this review we study such a modulation effect in directional and undirectional experiments. We calculate both the differential and the total rates using symmetric as well as asymmetric velocity distributions. We find that in the symmetric case the modulation amplitude is small, less than 0.07. There exist, however, regions of the phase sp...

  16. Probing the effect of different cross-sections in asymmetric collisions

    OpenAIRE

    Kaur, Deepinder; Kaur, Varinderjit; Kumar, Suneel

    2011-01-01

    We present a complete systematic theoretical study of multifragmentation for asymmetric colliding nuclei for heavy-ion reactions in the energy range between 50 MeV/nucleon and 1000 MeV/nucleon by using isospin dependent quantum molecular dynamics (IQMD) model. We have observed an interesting outcome for asymmetric colliding nuclei. The comparison between the symmetric and asymmetric colliding nuclei for the isospin independent cross section and isospin dependent cross section has been studied...

  17. The Determinants of the Asymmetric Power Effects in the context of Public-Private Partnership negotiation (PPP): theoretical Analysis and basic assumptions.

    OpenAIRE

    FAKHRI, ISSAOUI; TORKIA, BOUSSIF

    2016-01-01

    The principal aim of this paper is to present the problematic of the asymmetric power effect on public-private partnership. To do this we have mixed the works on PPP and those focusing on asymmetric power on commercial negotiation. This methodology allows us to determine the theoretical variables (in the form of hypothesis) which can be linked to the asymmetric power effect, on PPP negotiation.

  18. Asymmetric collider

    International Nuclear Information System (INIS)

    The study of CP violation in beauty decay is one of the key challenges facing high energy physics. Much work has not yielded a definitive answer how this study might best be performed. However, one clear conclusion is that new accelerator facilities are needed. Proposals include experiments at asymmetric electron-positron colliders and in fixed-target and collider modes at LHC and SSC. Fixed-target and collider experiments at existing accelerators, while they might succeed in a first observation of the effect, will not be adequate to study it thoroughly. Giomataris has emphasized the potential of a new approach to the study of beauty CP violation: the asymmetric proton collider. Such a collider might be realized by the construction of a small storage ring intersecting an existing or soon-to-exist large synchrotron, or by arranging collisions between a large synchrotron and its injector. An experiment at such a collider can combine the advantages of fixed-target-like spectrometer geometry, facilitating triggering, particle identification and the instrumentation of a large acceptance, while the increased √s can provide a factor > 100 increase in beauty-production cross section compared to Tevatron or HERA fixed-target. Beams crossing at a non-zero angle can provide a small interaction region, permitting a first-level decay-vertex trigger to be implemented. To achieve large √s with a large Lorentz boost and high luminosity, the most favorable venue is the high-energy booster (HEB) at the SSC Laboratory, though the CERN SPS and Fermilab Tevatron are also worth considering

  19. Effect of induced magnetic field on peristaltic flow of a micropolar fluid in an asymmetric channel

    CERN Document Server

    Shit, G C; Ng, E Y K; 10.1002/cnm.1397

    2010-01-01

    Of concern in this paper is an investigation of peristaltic transport of a physiological fluid in an asymmetric channel under long wave length and low-Reynolds number assumptions. The flow is assumed to be incompressible, viscous, electrically conducting micropolar fluid and the effect of induced magnetic field is taken into account. Exact analytical solutions obtained for the axial velocity, microrotation component, stream line pattern, magnetic force function, axial-induced magnetic field as well as the current density distribution across the channel. The flow phenomena for the pumping characteristics, trapping and reflux are also investigated. The results presented reveal that the velocity decreases with the increase of magnetic field as well as the coupling parameter. Moreover, the trapping fluid can be eliminated by the application of an external magnetic field. Thus, the study bears the promise of important applications in physiological systems.

  20. Effect of adiabatic square ribs on natural convection in an asymmetrically heated channel

    Science.gov (United States)

    Abidi-Saad, Aissa; Kadja, Mahfoud; Popa, Catalin; Polidori, Guillaume

    2016-06-01

    A 2-D numerical simulation is carried out to investigate the effect of two adiabatic square ribs on laminar flow and heat transfer in an asymmetrically heated channel. The two ribs are symmetrically located on each wall, exactly above the heating zone. The computational procedure is made by solving the unsteady bi-dimensional continuity, momentum and energy equations with the finite volume method. The investigations focused more specifically on the influence of ribs sizes on the flow structure and heat transfer enhancement. The results showed that the variation of ribs sizes significantly alters the heat transfer and fluid flow distribution along the channel, especially in the vicinity of protrusions. Also, the results show that streamlines, isotherms, and the number, sizes and formation of vortex structures inside the channel strongly depend on the size of protrusions. The changes in heat transfer parameters have also been presented.

  1. Effects of Microscopic Three-body Forces in Asymmetric Nuclear Matter

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The efiects of microscopic three-body forces on the equatioil of state(EOS)and the single particle properties of isospin asymmetric nuclear matter have been studied within Brueckner-Hartree-Fock framework~[1]The microscopic three-body force model constructed from meson exchange current approach in Ref.~[2] has been extended to isospin asymmetric nuclear matter

  2. Buoyancy Effects on Unsteady MHD Flow of a Reactive Third-Grade Fluid with Asymmetric Convective Cooling

    Directory of Open Access Journals (Sweden)

    Tirivanhu Chinyoka

    2015-01-01

    Full Text Available This article examines the combined effects of buoyancy force and asymmetrical convective cooling on unsteady MHD channel flow and heat transfer characteristics of an incompressible, reactive, variable viscosity and electrically conducting third grade fluid. The chemical kinetics in the flow system is exothermic and the asymmetric convective heat transfers at the channel walls follow the Newton’s law of cooling. The coupled nonlinear partial differential equations governing the problem are derived and solved numerically using a semi-implicit finite difference scheme. Graphical results are presented and physical aspects of the problem are discussed with respect to various parameters embedded in the system.

  3. Asymmetric Diketopyrrolopyrrole Conjugated Polymers for Field-Effect Transistors and Polymer Solar Cells Processed from a Nonchlorinated Solvent.

    Science.gov (United States)

    Ji, Yunjing; Xiao, Chengyi; Wang, Qiang; Zhang, Jianqi; Li, Cheng; Wu, Yonggang; Wei, Zhixiang; Zhan, Xiaowei; Hu, Wenping; Wang, Zhaohui; Janssen, René A J; Li, Weiwei

    2016-02-01

    Newly designed asymmetric diketopyrrolopyrrole conjugated polymers with two different aromatic substituents possess a hole mobility of 12.5 cm(2) V(-1) s(-1) in field-effect transistors and a power conversion efficiency of 6.5% in polymer solar cells, when solution processed from a nonchlorinated toluene/diphenyl ether mixed solvent.

  4. Asymmetric Effect of Monetary Policy on Stock Market Volatility in ASEAN5

    Directory of Open Access Journals (Sweden)

    Trung Thanh BUI

    2015-05-01

    Full Text Available Among many channels, stock market directly transmits the effect of monetary policy decisions because it quickly responds to policy news. The primary objective of this paper is to clarify the asymmetric effect of monetary policy on stock market volatility, which is believed to have adverse effects on the economy recovery, over its bull and bear period. We performed empirical research in a panel setting in which monthly data of ASEAN5 (Vietnam, Thailand, Philippines, Malaysia, and Indonesia was collected from January 2006 to June 2013. To reduce identification and endogeneity problem, we used short-term interest rate as a proxy for the stance of monetary policy. The Markov switching model was used to identify the bull and bear periods of stock market. We employed feasible GLS estimator to examine the possible asymmetry. The empirical results have demonstrated the existence of the asymmetry in the monetary policy effect on the stock market volatility over stock market cycle in ASEAN5. The findings have suggested that monetary policy is more effective in bear market and that a tight monetary policy increases the probability of shifting stock market from bullish to bearish state.

  5. Numerical Investigation of Size and Structure Effect on Tensile Characteristics of Symmetric and Asymmetric CNTs

    Directory of Open Access Journals (Sweden)

    Mahnaz Zakeri

    2016-06-01

    Full Text Available In this research, the influence of structure on the tensile properties of single- walled carbon nanotubes (CNTs is evaluated using molecular mechanics technique and finite element method. The effects of diameter, length and chiral angle on elastic modulus and Poisson’s ratio of armchair, zigzag and chiral structures are investigated. To simulate the CNTs, a 3D FEM code is developed using the ANSYS commercial software. Considering the carbon-carbon covalent bonds as connecting load-carrying beam elements, and the atoms as joints of the elements, CNTs are simulated as space-frame structures. The atomic potentials are estimated using harmonic simple functions. The numerical results show that by increasing the diameter and length to a certain amount, the size effect on tensile behavior of modeled nanotubes is omitted. In fact, for nanotubes with diameter over 2 nm and length over 36.5 nm the chiral angle is the only effective factor on the tensile properties. Also, it is found that the structure has a little effect on the elasticity modulus, which is about 4%. However, Poisson’s ratio can be affected significantly with chiral angle. Asymmetric structures with angles θ

  6. Directed flow in asymmetric nucleus-nucleus collisions and the inverse Landau-Pomeranchuk-Migdal effect

    CERN Document Server

    Toneev, V D; Kolomeitsev, E E; Cassing, W

    2016-01-01

    It is proposed to identify a strong electric field - created during relativistic collisions of asymmetric nuclei - via the observation of pseudorapidity and transverse momentum distributions of hadrons with the same mass but opposite charge. The results of detailed calculations within the Parton-Hadron String Dynamics (PHSD) approach for the charge-dependent directed flow $v_1$ are presented for semi-central Cu+Au collision at $\\sqrt{s_{NN}}=200$ GeV incorporating the inverse Landau-Pomeranchuk-Migdal (iLPM) effect, which accounts for a delay in the electromagnetic interaction with the charged degree of freedom. Including the iLPM effect we achieve a reasonable agreement of the PHSD results for the charge splitting in $v_1(p_T)$ in line with the recent measurements of the STAR Collaboration for Cu+Au collisions at $\\sqrt{s_{NN}}=200$ GeV while an instant appearance and coupling of electric charges at the hard collision vertex overestimates the splitting by about a factor of 10. We predict that the iLPM effect...

  7. Effect of unequal load of carbon xerogel in electrodes on the electrochemical performance of asymmetric supercapacitors

    OpenAIRE

    Gómez Calvo, Esther; Lufrano, F.; Arenillas de la Puente, Ana; Brigandi, A.; Menéndez Díaz, José Ángel; Staiti, P.

    2013-01-01

    This paper investigates the electrochemical performance of asymmetric supercapacitors in an environmentally friendly aqueous electrolyte (1.0 mol L−1 sodium sulfate solution). The asymmetric configuration is based on the use of a highly porous carbon xerogel as active material in both the positive and negative electrodes, but the carbon xerogel loading in each electrode has been substantially modified. This configuration leads to an increase in the operational voltage window up to values of 1...

  8. Asymmetric Hydrogenation of α-Hydroxy Ketones: A Reaction Sensitive toward Electronic Effect of Substrates

    Institute of Scientific and Technical Information of China (English)

    XU Hui; MENG Qing-Hua; ZHANG Zhao-Guo

    2008-01-01

    An efficient asymmetric hydrogenation of a-hydroxy ketones was reported with the catalyst prepared from [RuCl2(benzene)]2 and SunPhos,chiral terminal 1,2-diols were obtained in up to 99% ee.This Ru-catalyzed asymmetric hydrogenation reaction of a-hydroxy ketones represents a new route for the synthesis of chiral terminal 1,2-diols.

  9. Recent observations of human-induced asymmetric effects on climate in very high-altitude area.

    Directory of Open Access Journals (Sweden)

    Heli Lu

    Full Text Available Like urban heat islands (UHI, human-induced land degradation (HLD is a phenomenon attributed to human activities, but this phenomenon occurs in non-urban areas. Although a large body of work has demonstrated that land-cover change influences local climate systems, little work has been done on separating the impact of HLD from naturally-occurring fluctuations in very high-altitude areas. We developed an innovative NDVI-difference method in order to evaluate HLD effects upon the climate system in the central Tibet Plateau. The results show that the minimum temperature increased at a significantly faster pace than the maximum temperature in the growing season at HLD meteorological stations, but this was reversed at stations with natural forces only. Further analysis revealed that abrupt changes of minimum temperature occurred five years earlier and amplitudes of these changes were 1.4 times larger than at stations with natural forces only. Therefore, our results complement other evidence that points to the fact that local effects from UHI contribute to climatic asymmetry observed between minimum and maximum temperature trends. Accordingly, we stress the need for consideration of non-urban factors from anthropogenic activities, such as human-induced land degradation, in understanding these asymmetric diurnal changes.

  10. Effective Hamiltonian for a half-filled asymmetric ionic Hubbard chain with alternating on-site interaction

    Science.gov (United States)

    Grusha, I.; Menteshashvili, M.; Japaridze, G. I.

    2016-01-01

    We derive an effective spin Hamiltonian for the one-dimensional half-filled asymmetric ionic Hubbard model (IHM) with alternating on-site interaction in the limit of strong repulsion. It is shown that the effective Hamiltonian is that of a spin S = 1/2 anisotropic XXZ Heisenberg chain with alternating next-nearest-neighbor (NNN) and three-spin couplings in the presence of a uniform and a staggered magnetic field.

  11. Effect of coagulant bath on the gas permeation properties of cellulose acetate asymmetric membrane

    Science.gov (United States)

    Mohamed, F.; Hasbullah, H.; Jami'an, W. N. R.; Salleh, W. N. H. W.; Ibrahim, N.; Ali, R. R.

    2016-06-01

    Membrane based gas separation process technology has been recognized as one of the most efficient and advanced unit operation for gas separation. One of the problems in membrane gas separation is membrane performance. This paper explores the application of cellulose acetate (CA) membrane for natural gas purification and separation by improving its permeability and selectivity. The main interest in this research is to study the effect of quench medium on the gas separation performance towards its physical characteristics and gas separation performance of CA membrane. Cellulose acetate polymer was dissolved in n- methyl-2-pyrrolidone solvent and casted onto a glass plate using a pneumatically controlled casting system with fixed shear rate and solvent evaporation times. The parameter varied was the non-solvent used as quench medium during membrane post treatment that were methanol and n-hexane. The different quench media as post treatment affected the O2 and N2 gas permeation and O2/N2 selectivity as well as the tensile strength of the flat sheet asymmetric membrane. Combination of methanol and n-hexane as quench media gave the best result than the other steps. This solvent exchange step influenced the morphology by producing thin skin layer and thus gives better gas separation performance than other steps

  12. Examining the asymmetrical effects of goal faultlines in groups: a categorization-elaboration approach.

    Science.gov (United States)

    Ellis, Aleksander P J; Mai, Ke Michael; Christian, Jessica Siegel

    2013-11-01

    The purpose of this study was to use the categorization-elaboration model (CEM) to examine the asymmetrical effects of goal faultlines in groups, which are present when hypothetical dividing lines are created on the basis of different performance goals, splitting the group into subgroups. On the basis of the CEM, we expected groups with goal faultlines to exhibit higher levels of creative task performance than (a) groups with specific, difficult goals and (b) groups with do-your-best goals. We expected the benefits of goal faultlines to be due to increases in reflective reframing, which occurs when group members build on each other's ideas by shifting to alternate frames. However, we expected groups with goal faultlines to exhibit lower levels of routine task performance than (a) groups with do-your-best goals and (b) groups with specific, difficult goals, due to increased perceptions of loafing. Results from 87 groups generally supported our hypothesized model. Implications are discussed as well as possible limitations and directions for future research. PMID:23855916

  13. G-quadruplex DNA-based asymmetric catalysis of michael addition: Effects of sonication, ligands, and co-solvents.

    Science.gov (United States)

    Zhao, Hua; Shen, Kai

    2016-07-01

    There is an escalating interest of using double stranded DNA molecules as a chiral scaffold to construct metal-biomacromolecule hybrid catalysts for asymmetric synthesis. Several recent studies also evaluated the use of G-quadruplex DNA-based catalysts for asymmetric Diels-Alder and Friedel-Crafts reactions. However, there is still a lack of understanding of how different oligonucleotides, salts (such as NaCl and KCl), metal ligands and co-solvents affect the catalytic performance of quadruplex DNA-based hybrid catalysts. In this study, we aim to systematically evaluate these key factors in asymmetric Michael addition reactions, and to examine the conformational and molecular changes of DNA by circular dichroism (CD) spectroscopy and gel electrophoresis. We achieved up to 95% yield and 50% enantiomeric excess (ee) when the reaction of 2-acylimidazole 1a and dimethylmalonate was catalyzed by 5'-G3 (TTAG3 )3 -3' (G4DNA1) in 20 mM MOPS (pH 6.5) containing 50 mM KCl and 40 µM [Cu(dmbipy)(NO3 )2 ], and G4DNA1 was pre-sonicated in ice bath for 10 min prior to the reaction. G-quadruplex-based hybrid catalysts provide a new tool for asymmetric catalysis, but future mechanistic studies should be sought to further improve the catalytic efficiency. The current work presents a systematic study of asymmetric Michael addition catalyzed by G-quadruplex catalysts constructed via non-covalent complexing, and an intriguing finding of the effect of pre-sonication on catalytic efficiency. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:891-898, 2016. PMID:27090055

  14. Effect of the Shafranov shift and the gradient of $\\beta$ on intrinsic momentum transport in up-down asymmetric tokamaks

    CERN Document Server

    Ball, Justin; Lee, Jungpyo; Cerfon, Antoine J

    2016-01-01

    Tokamaks with up-down asymmetric poloidal cross-sections spontaneously rotate due to turbulent transport of momentum. In this work, we investigate the effect of the Shafranov shift on this intrinsic rotation, primarily by analyzing tokamaks with tilted elliptical flux surfaces. By expanding the Grad-Shafranov equation in the large aspect ratio limit we calculate the magnitude and direction of the Shafranov shift in tilted elliptical tokamaks. The results show that, while the Shafranov shift becomes up-down asymmetric and depends strongly on the tilt angle of the flux surfaces, it is insensitive to the shape of the current and pressure profiles (when specific experimental parameters are kept fixed). Next, local nonlinear gyrokinetic simulations of these MHD equilibria are performed with GS2, which reveal that the Shafranov shift can significantly enhance the momentum transport. However, to be consistent, the effect of $\\beta'$ (i.e. the radial gradient of $\\beta$) on the magnetic equilibrium was also included....

  15. Effect of plate asymmetric rolling parameters on the change of the total unit pressure of roll

    Directory of Open Access Journals (Sweden)

    A. Kawalek

    2011-07-01

    Full Text Available This work shows the results of theoretical analysis of asymmetric rolling process of plates in the finishing mill of plate rolling. Its aim was to determine the influence of asymmetry velocity of working rolls on decrease of unit pressure of metal on the rolls. The lower value of the unit pressure will reduce the elastic deflection of the finishing stand and improve the cross-section shape of plate. Three-dimensional simulation of asymmetric hot rolling of S355J2G3 steel plates was done with the aid of FORGE 2008® software. The tensor polynomial interpolation was used for comparing the values of the unit pressure obtaining from symmetric and asymmetric rolling.

  16. Simultaneous effects of Hall and convective conditions on peristaltic flow of couple-stress fluid in an inclined asymmetric channel

    Indian Academy of Sciences (India)

    T Hayat; Maryam Iqbal; Humaira Yasmin; Fuad E Alsaadi; Huijun Gao

    2015-07-01

    A mathematical model is developed to analyse the peristaltic flow of couple-stress fluid in an inclined asymmetric channel with convective conditions. Soret and Dufour and Hall effects are taken into account. Analysis has been carried out in a wave frame of reference. Expressions for velocity, pressure gradient, temperature and concentration are constructed. Pumping and trapping phenomena are examined. Impact of sundry parameters on the velocity, temperature and concentration is discussed.

  17. Alternative Asymmetric Stochastic Volatility Models

    NARCIS (Netherlands)

    M. Asai (Manabu); M.J. McAleer (Michael)

    2010-01-01

    textabstractThe stochastic volatility model usually incorporates asymmetric effects by introducing the negative correlation between the innovations in returns and volatility. In this paper, we propose a new asymmetric stochastic volatility model, based on the leverage and size effects. The model is

  18. The Asymmetric Effects of Oil Price Shocks on the Chinese Stock Market: Evidence from a Quantile Impulse Response Perspective

    Directory of Open Access Journals (Sweden)

    Huiming Zhu

    2016-08-01

    Full Text Available This paper uses a quantile impulse response approach to investigate the impact of oil price shocks on Chinese stock returns. This process allows us to uncover asymmetric effects of oil price shocks on stock market returns by taking into account the different quantiles of oil price shocks. Our results show that the responses of Chinese stock market returns to oil price shocks differ greatly, depending on whether the oil and stock market is in a bust or boom state and whether the shock is driven by demand or supply. The impacts of oil price shocks on Chinese stock returns present asymmetric features. In particular during a bust phase, oil supply and demand shocks significantly depress stock market returns, while during a boom period, the aggregate demand shock enhances stock market returns. These results suggest some important implications for investors and decision makers.

  19. The effect of asymmetric barrier layers in the waveguide region on power characteristics of QW lasers

    DEFF Research Database (Denmark)

    Zubov, F. I.; Zhukov, A. E.; Shernyakov, Yu M.;

    2015-01-01

    Current-voltage and light-current characteristics of quantum-well lasers have been studied at high drive currents. The introduction of asymmetric barrier layers adjacent to the active region caused a significant suppression of the nonlinearity in the light-current characteristic and an increase in...... the external differential efficiency. As a result, the maximum wallplug efficiency increased by 9%, while the output optical power increased by 29%....

  20. Higher-order effects on the incompressibility of isospin asymmetric nuclear matter

    OpenAIRE

    Chen, Lie-Wen; Cai, Bao-Jun; Ko, Che Ming; Li, Bao-An(Department of Physics and Astronomy, Texas A&M University-Commerce, Commerce, TX, 75429-3011, USA); Shen, Chun; Xu, Jun

    2009-01-01

    Analytical expressions for the saturation density as well as the binding energy and incompressibility at the saturation density of asymmetric nuclear matter are given exactly up to 4th-order in the isospin asymmetry delta =(rho_n - rho_p)/rho using 11 characteristic parameters defined at the normal nuclear density rho_0. Using an isospin- and momentum-dependent modified Gogny (MDI) interaction and the SHF approach with 63 popular Skyrme interactions, we have systematically studied the isospin...

  1. Testing the Asymmetric Effects of Financial Conditions in South Africa: A Nonlinear Vector Autoregression Approach

    OpenAIRE

    Mehmet Balcilar; Kirsten Thompson; Rangan Gupta; Renee van Eyden

    2014-01-01

    The negative consequences of financial instability for the world economy during the recent financial crisis have highlighted the need for a better understanding of financial conditions. We use a financial conditions index (FCI) for South Africa previously constructed from 16 financial variables to test whether the South African economy responds in a nonlinear and asymmetric way to unexpected changes in financial conditions. To this end, we make use of a nonlinear logistic smooth transition ve...

  2. Mixed convective heat and mass transfer analysis for peristaltic transport in an asymmetric channel with Soret and Dufour effects

    Institute of Scientific and Technical Information of China (English)

    F M Abbasi; A Alsaedi; T Hayat

    2014-01-01

    The present investigation addresses the simultaneous effects of heat and mass transfer in the mixed convection peristaltic flow of viscous fluid in an asymmetric channel. The channel walls exhibit the convective boundary conditions. In addition, the effects due to Soret and Dufour are taken into consideration. Resulting problems are solved for the series solutions. Numerical values of heat and mass transfer rates are displayed and studied. Results indicate that the concentration and temperature of the fluid increase whereas the mass transfer rate at the wall decreases with increase of the mass transfer Biot number. Furthermore, it is observed that the temperature decreases with the increase of the heat transfer Biot number.

  3. Asymmetric Effect of Oil Price on the Terms of Trade: Evidence from Oil Exporting and Importing Countries

    OpenAIRE

    Mahmoud Mahmoudzadeh; Somaye Sadeghi; Soraya Sadeghi

    2012-01-01

    The oil price shocks are an important source that affect on TOT in both oil exporting and importing countries. Hence, this paper compares the effects of real oil price shock on TOT in both oil importing and exporting countries, using Panel Data technique and during 1980-2010. To the best of our knowledge, we applied the nonlinear approach in order to assess the asymmetric impact of the oil price shocks on TOT. The results show that the oil price shocks influenced the TOT in the oil exporting ...

  4. Peristaltic flow of a couple stress fluid under the effect of induced magnetic field in an asymmetric channel

    Energy Technology Data Exchange (ETDEWEB)

    Nadeem, Sohail; Akram, Safia [Quaid-i-Azam University, Department of Mathematics, Islamabad (Pakistan)

    2011-01-15

    The present paper investigates the peristaltic transport of a couple stress fluid in an asymmetric channel with the effect of the induced magnetic field. The exact solutions of momentum and the magnetic field equations have been calculated under the assumptions of long wave length and low but finite Reynolds number. The expression for pressure rise has been computed numerically using mathematics software Mathematica. The graphical results have been presented to discuss the physical behavior of various physical parameters of interest. Finally, the trapping phenomena have been discussed for various physical parameters. (orig.)

  5. Effect of isospin-dependent cross-section on fragment production in the collision of charge asymmetric nuclei

    Indian Academy of Sciences (India)

    Anupriya Jain; Suneel Kumar

    2012-05-01

    To understand the role of isospin effects on fragmentation due to the collisions of charge asymmetric nuclei, we have performed a complete systematical study using isospin-dependent quantum molecular dynamics model. Here simulations have been carried out for ${}^{124}X_n + {}^{124}X_n$ ,where varies from 47 to 59 and for 40Y$_m$ + 40Y$_m$ , where varies from 14 to 23. Our study shows that isospin-dependent cross-section shows its influence on fragmentation in the collision of neutron-rich nuclei.

  6. Effects of information feedback on an asymmetrical two-route scenario

    Institute of Scientific and Technical Information of China (English)

    SUN XiaoYan; WANG BingHong; YANG HanXin; WANG QiaoMing; JIANG Rui

    2009-01-01

    In traffic system,a reasonable information feedback can improve road capacity. In this paper,we investigate an asymmetrical two-route scenario in which dynamic information can be generated and displayed on the board to guide drivers. Two improved feedbacks (i.e. improved mean velocity feedback and improved congestion coefficient feedback) are introduced. Simulations show that the average cost is dependent on the vehicle arrival rate and there exists a critical the dynamic vehicles ratio corresponding to the maximum flux. We find that improved con-gestion coefficient can better enhance the system capacity than that of improved mean velocity feedback.

  7. Effectiveness of Asymmetrical Veneering with Hardwood Species of Varying Shrinkage and Porosity

    Directory of Open Access Journals (Sweden)

    Oleńska Sylwia

    2014-06-01

    Full Text Available The aim of the study was to check deformations of asymmetrically veneered panels using glue with elastic bonding. In order to achieve the aim, a special stand was designed to analyse the geometry of furniture elements. It is known that boards became convex after veneering with rigid glue. However, the level of deformations for varying parameters of veneering was not equal. As the result of veneering with elastic glue, the boards preserved their primary shape. In any case, the level of deformation depended on wood veneer species. The deformation of the boards was not influenced by their shrinkage. It is supposed that the main influence is the difference in porosity.

  8. Asymmetric Exchange Rate Exposures: A Search for the Effect of Real Options

    DEFF Research Database (Denmark)

    Aabo, Tom

    2001-01-01

    Real options like the ability to reallocate production resources can lead to an asymmetric exchange rate exposure. Using a stock market approach in which the exchange rate exposure is derived from the information content in the stock prices this study examines the extra-market exchange rate...... exchange rate exposures are identified successfully but the asymmetries can only to a limited extent be explained by the existence of real options. Financial options and pricing to market are competing explanations. Omitted variable bias further blurs the picture. These problems and the concept of path...

  9. Transverse effects in a microchip laser with asymmetric end-pumping: modal interference and dynamic instability

    CERN Document Server

    Otsuka, K; Makino, H; Ohtomo, T; Okamoto, A

    2003-01-01

    Formation of complicated emission patterns consisting of many transverse modes and associated intensity pulsations at beat frequencies between some pairs of transverse eigenmodes in microchip solid-state lasers with laser-diode asymmetric end-pumping are reviewed. The dependence of billiard-like transverse patterns on pump power and crystal rotation (i.e. kaleidoscopic patterns) was demonstrated in a 0.3 mm thick thin-slice LiNdP sub 4 O sub 1 sub 2 laser with sheet-like end-pumping. Pump-power-dependent high-speed self-pulsations were observed. The asymmetric optical confinement resulted in the formation of transverse patterns which were totally different from normal Hermite-Gaussian resonator modes. The interference among pairs of non-orthogonal transverse eigenmode fields, whose energy levels exhibited avoided crossing with increasing pump power, was shown to result in high-speed intensity modulations. A good numerical reproduction of the observed high-speed modulations was obtained with model equations. (...

  10. Effects of asymmetric cultural experiences on the auditory pathway: evidence from music.

    Science.gov (United States)

    Wong, Patrick C M; Perrachione, Tyler K; Margulis, Elizabeth Hellmuth

    2009-07-01

    Cultural experiences come in many different forms, such as immersion in a particular linguistic community, exposure to faces of people with different racial backgrounds, or repeated encounters with music of a particular tradition. In most circumstances, these cultural experiences are asymmetric, meaning one type of experience occurs more frequently than other types (e.g., a person raised in India will likely encounter the Indian todi scale more so than a Westerner). In this paper, we will discuss recent findings from our laboratories that reveal the impact of short- and long-term asymmetric musical experiences on how the nervous system responds to complex sounds. We will discuss experiments examining how musical experience may facilitate the learning of a tone language, how musicians develop neural circuitries that are sensitive to musical melodies played on their instrument of expertise, and how even everyday listeners who have little formal training are particularly sensitive to music of their own culture(s). An understanding of these cultural asymmetries is useful in formulating a more comprehensive model of auditory perceptual expertise that considers how experiences shape auditory skill levels. Such a model has the potential to aid in the development of rehabilitation programs for the efficacious treatment of neurologic impairments. PMID:19673772

  11. Monaural Beamforming in Bimodal Cochlear Implant Users: Effect of (A)symmetric Directivity and Noise Type

    Science.gov (United States)

    Janssen, A. Miranda L.; Chalupper, Josef; Stokroos, Robert J.; George, Erwin L. J.

    2016-01-01

    Objective To evaluate monaural beamforming in bimodally aided cochlear implant (CI) users. Design The study enrolled twelve adult bimodal listeners with at least six months of CI-experience and using a contralateral hearing aid (HA) most of the daytime. Participants were uniformly fitted with the same CI speech processor and HA, giving access to an identical monaural beamformer in both ears. A within-subject repeated measures design evaluated three directional configurations [omnidirectional, asymmetric directivity (in CI alone) and symmetric directivity (in both CI and HA)] in two noise types [stationary and fluctuating]. Bimodal speech reception thresholds (SRT) as well as listening effort ratings were assessed in a diffuse noise field. Results Symmetric monaural beamforming provided a significant SRT improvement of 2.6 dB SNR, compared to 1.6 dB SNR for asymmetric monaural beamforming. Directional benefits were similarly observed in stationary and fluctuating noise. Directivity did not contribute to less listening effort in addition to improvement in speech intelligibility. Bimodal performance was about 7 dB SNR worse in fluctuating than in stationary noise. Conclusions Monaural beamforming provided substantial benefit for speech intelligibility in noise for bimodal listeners. The greatest benefit occurred when monaural beamforming was activated symmetrically in both CI and HA. Monaural beamforming does not bridge the gap between bimodal and normal hearing performance, especially in fluctuating noise. Results advocate further bimodal co-operation. Trial Registration This trial was registered in www.trialregister.nl under number NTR4901. PMID:27537075

  12. The role of asymmetric interactions on the effect of habitat destruction in mutualistic networks.

    Directory of Open Access Journals (Sweden)

    Guillermo Abramson

    Full Text Available Plant-pollinator mutualistic networks are asymmetric in their interactions: specialist plants are pollinated by generalist animals, while generalist plants are pollinated by a broad range involving specialists and generalists. It has been suggested that this asymmetric--or disassortative--assemblage could play an important role in determining the observed equal susceptibility of specialist and generalist plants under habitat destruction. At the core of the analysis of the phenomenon lies the observation that specialist plants, otherwise candidates to extinction, could cope with the disruption thanks to their interaction with a few generalist pollinators. We present a theoretical framework that supports this thesis. We analyze a dynamical model of a system of mutualistic plants and pollinators, subject to the destruction of their habitat. We analyze and compare two families of interaction topologies, ranging from highly assortative to highly disassortative ones, as well as real pollination networks. We found that several features observed in natural systems are predicted by the mathematical model. First, there is a tendency to increase the asymmetry of the network as a result of the extinctions. Second, an entropy measure of the differential susceptibility to extinction of specialist and generalist species show that they tend to balance when the network is disassortative. Finally, the disappearance of links in the network, as a result of extinctions, shows that specialist plants preserve more connections than the corresponding plants in an assortative system, enabling them to resist the disruption.

  13. Effect of radiation and magnetic field on peristaltic transport of nanofluids through a porous space in a tapered asymmetric channel

    Energy Technology Data Exchange (ETDEWEB)

    Kothandapani, M., E-mail: mkothandapani@gmail.com [Department of Mathematics, University College of Engineering Arni, (A Constituent College of Anna University Chennai), Arni 632326, Tamil Nadu (India); Prakash, J., E-mail: prakashjayavel@yahoo.co.in [Department of Mathematics, Arulmigu Meenakshi Amman College of Engineering, Vadamavandal 604410, Tamil Nadu (India)

    2015-03-15

    Theoretical analyses on the effect of radiation and MHD on the peristaltic flow of a nanofluid through a porous medium in a two dimensional tapered asymmetric channel has been made. The nanofluid is assumed to be electrically conducting in the presence of a uniform magnetic field. The transport equation accounts the both Brownian motion and thermophoresis along with the radiation reaction. The problem has been further simplified with the authentic assumptions of long wavelength and small Reynolds number. The analytical expressions obtained for the axial velocity, stream function, temperature field, nanoparticle fraction field and pressure gradient provide satisfactory explanation. Influence of various parameters on the flow characteristics have been discussed with the help of graphical results. The trapping phenomenon has also been discussed in detail. - Highlights: • Combine effect of thermal radiation and MHD on the peristaltic flow of a Newtonian nanofluid are discussed. • This work may be first attempt dealing the study of Newtonian nanofluid flow in the porous tapered asymmetric channel. • The velocity, stream function, temperature field and nanoparticle fraction field provide satisfactory explanation with help of graphs.

  14. Modelling asymmetric growth in crowded plant communities

    DEFF Research Database (Denmark)

    Damgaard, Christian

    2010-01-01

    A class of models that may be used to quantify the effect of size-asymmetric competition in crowded plant communities by estimating a community specific degree of size-asymmetric growth for each species in the community is suggested. The model consists of two parts: an individual size-asymmetric ......A class of models that may be used to quantify the effect of size-asymmetric competition in crowded plant communities by estimating a community specific degree of size-asymmetric growth for each species in the community is suggested. The model consists of two parts: an individual size...

  15. Effect of asymmetric hot rolling on texture, microstructure and magnetic properties in a non-grain oriented electrical steel

    International Nuclear Information System (INIS)

    In this study, both asymmetric hot rolling (AHR) and conventional hot rolling (CHR) were carried out to study the effect of the hot rolling conditions on the evolution of the texture and microstructure in a non-grain oriented (NGO) steel. The microstructure and texture in the subsequent processing stages were characterised and related to the final magnetic properties. The results show that AHR, compared with CHR, tends to homogenise texture through thickness of the hot band strips. AHR results in a higher fraction of the θ-fibre ({0 0 1}) and a lower fraction of the γ-fibre ({1 1 1}) in the hot band strips, which are favourable features in relation to the magnetic properties of the strip. However, the favourable features observed in hot rolled AHR strips are eliminated after cold rolling and annealing. Contrarily, the required θ-fibre is decreased and the unwanted γ-fibre is intensified in the AHR sheet after cold rolling and their strength is maintained in the subsequent process steps. On the other hand, AHR does not produce a discernible change in the grain size in the hot band annealed strip and in the final annealed sheet, except that the magnetic anisotropy in the AHR is improved after skin pass and extra annealing as the result of the redistribution of the texture components within the θ-fibre, no significant improvement of the magnetic properties as a direct consequence of the application of asymmetric hot rolling has been observed under the current AHR experimental conditions. - Highlights: • Asymmetrical hot rolling (AHR) produces more uniform distribution of texture through the thickness of the hot rolled strips and of the hot band annealed strips when compared with conventional hot rolling (CHR). • AHR results in a higher fraction of the θ-fibre ({0 0 1}) and a lower fraction of the γ-fibre ({1 1 1}) in the hot band strips. The θ-fibre is decreased but the γ-fibre is intensified in the AHR sheet after cold rolling

  16. Effect of asymmetric hot rolling on texture, microstructure and magnetic properties in a non-grain oriented electrical steel

    Energy Technology Data Exchange (ETDEWEB)

    Chen, S., E-mail: Shangping.chen@tatasteel.com [Tata Steel, 1970 CA IJmuiden (Netherlands); Butler, J. [Tata Steel, S60 3AR South Yorkshire (United Kingdom); Melzer, S. [Tata Steel, 1970 CA IJmuiden (Netherlands)

    2014-11-15

    In this study, both asymmetric hot rolling (AHR) and conventional hot rolling (CHR) were carried out to study the effect of the hot rolling conditions on the evolution of the texture and microstructure in a non-grain oriented (NGO) steel. The microstructure and texture in the subsequent processing stages were characterised and related to the final magnetic properties. The results show that AHR, compared with CHR, tends to homogenise texture through thickness of the hot band strips. AHR results in a higher fraction of the θ-fibre ({0 0 1}) and a lower fraction of the γ-fibre ({1 1 1}) in the hot band strips, which are favourable features in relation to the magnetic properties of the strip. However, the favourable features observed in hot rolled AHR strips are eliminated after cold rolling and annealing. Contrarily, the required θ-fibre is decreased and the unwanted γ-fibre is intensified in the AHR sheet after cold rolling and their strength is maintained in the subsequent process steps. On the other hand, AHR does not produce a discernible change in the grain size in the hot band annealed strip and in the final annealed sheet, except that the magnetic anisotropy in the AHR is improved after skin pass and extra annealing as the result of the redistribution of the texture components within the θ-fibre, no significant improvement of the magnetic properties as a direct consequence of the application of asymmetric hot rolling has been observed under the current AHR experimental conditions. - Highlights: • Asymmetrical hot rolling (AHR) produces more uniform distribution of texture through the thickness of the hot rolled strips and of the hot band annealed strips when compared with conventional hot rolling (CHR). • AHR results in a higher fraction of the θ-fibre ({0 0 1}) and a lower fraction of the γ-fibre ({1 1 1}) in the hot band strips. The θ-fibre is decreased but the γ-fibre is intensified in the AHR sheet after cold rolling

  17. Essays in applied macroeconomics: Asymmetric price adjustment, exchange rate and treatment effect

    Science.gov (United States)

    Gu, Jingping

    This dissertation consists of three essays. Chapter II examines the possible asymmetric response of gasoline prices to crude oil price changes using an error correction model with GARCH errors. Recent papers have looked at this issue. Some of these papers estimate a form of error correction model, but none of them accounts for autoregressive heteroskedasticity in estimation and testing for asymmetry and none of them takes the response of crude oil price into consideration. We find that time-varying volatility of gasoline price disturbances is an important feature of the data, and when we allow for asymmetric GARCH errors and investigate the system wide impulse response function, we find evidence of asymmetric adjustment to crude oil price changes in weekly retail gasoline prices. Chapter III discusses the relationship between fiscal deficit and exchange rate. Economic theory predicts that fiscal deficits can significantly affect real exchange rate movements, but existing empirical evidence reports only a weak impact of fiscal deficits on exchange rates. Based on US dollar-based real exchange rates in G5 countries and a flexible varying coefficient model, we show that the previously documented weak relationship between fiscal deficits and exchange rates may be the result of additive specifications, and that the relationship is stronger if we allow fiscal deficits to impact real exchange rates non-additively as well as nonlinearly. We find that the speed of exchange rate adjustment toward equilibrium depends on the state of the fiscal deficit; a fiscal contraction in the US can lead to less persistence in the deviation of exchange rates from fundamentals, and faster mean reversion to the equilibrium. Chapter IV proposes a kernel method to deal with the nonparametric regression model with only discrete covariates as regressors. This new approach is based on recently developed least squares cross-validation kernel smoothing method. It can not only automatically smooth

  18. Observation of the effective linear polarization induced by the asymmetrical Raman gain of YVO4 crystal

    Science.gov (United States)

    Zhuang, Fengjiang; Lin, Zhiyang; Zhu, Siqi

    2016-10-01

    We originally present a linearly polarized Raman radiation emitted from an actively Q-switched Nd:YAG/YVO4 laser. An 1175.25 nm Raman output was achieved using a uniaxial a-cut YVO4 crystal in a Z-shape laser cavity. The stable Raman power of 1.8 W was obtained, corresponding conversion efficiency of 8.8% from 1064 nm to 1175 nm. The Raman radiation with a polarization extinction ratio of 10.4-dB was observed for the first time. Our experimental results demonstrate that the asymmetrical Raman crystal gain can result in a uniform linear polarization and permit emitting orthogonal polarization radiation in a cascaded Raman laser.

  19. Effect of Asymmetric Potential and Gaussian Colored Noise on Stochastic Resonance

    Institute of Scientific and Technical Information of China (English)

    HAN Yin-Xia; LI Jing-Hui; CHEN Shi-Gang

    2005-01-01

    The phenomenon of stochastic resonance (SR) in a bistable nonlinear system is studied when the system is driven by the asymmetric potential and additive Gaussian colored noise. Using the unified colored noise approximation method, the additive Gaussian colored noise can be simplified to additive Gaussian white noise. The signal-to-noise ratio (SNR) is calculated according to the generalized two-state theory (shown in [H.S. Wio and S. Bouzat, Brazilian J.Phys. 29 (1999) 136]). We find that the SNR increases with the proximity of a to zero. In addition, the correlation time τ between the additive Gaussian colored noise is also an ingredient to improve SR. The shorter the correlation time τ between the Gaussian additive colored noise is, the higher of the peak value of SNR.

  20. Tunable plasmon-induced transparency effect based on self-asymmetric H-shaped resonators meta-atoms

    Science.gov (United States)

    Cheng, Zhaoxiang; Chen, Lin; Zang, Xiaofei; Cai, Bin; Peng, Yan; Zhu, Yiming

    2015-03-01

    We have proposed and demonstrated a tunable plasmon-induced transparency (PIT) effect from two ways, based on self-asymmetric H-shaped resonators (AHR) meta-atoms. The tunable PIT effect is realized via varying polarization angles and coupling distances. First, by proper design, transition from PIT mode to dipole mode is theoretically and experimentally demonstrated by simply adjusting the polarization angle. Also, the manipulation of ‘dark-mode’ resonance intensity from strong to weak is achieved by varying coupling strength with different distances, which provided insight into the magnetic coupling hybridization mechanism. Prospectively, due to its special tunable characteristics, the AHR meta-atoms may be widely used in slow light, filters and switch devices.

  1. Assessment of protocols in cone beam CT with symmetric and asymmetric beam using effective dose and Pka

    International Nuclear Information System (INIS)

    The cone beam CT is an emerging technology in dental radiology with significant differences the point of view of design technology between the various manufacturers on the world market. This study aims to evaluate and compare protocols with similar purposes in a cone beam CT scanner using TLDs and air kerma - area product (Pka) as kerma index. Measurements were performed on two protocols used to obtain the image the maxilla-mandible in equipment Gendex GXCB 500: Protocol [GX1] extended diameter and asymmetric beam (14 cm x 8.5 cm - maxilla / mandible) and protocol [GX2] symmetrical beam (8.5 cm x 8.5 cm - maxillary / mandible). Was used LiF dosimeters (TLD 100) inserted into a female anthropomorphic phantom manufactured by Radiology Support Devices. For all protocols evaluated the value of Pka using a meter Diamentor E2 and PTW system Radcal Rapidose. The results obtained for Effective Dose / Pka these measurements were separated by protocol image. Protocol [GX1]: 44.5 μSv/478 mGy cm2; protocol [GX2]: 54.8 μSv/507 mGy cm2. These values indicate that the relationship between the diameter of the image acquired in the protocol [GX1] and the diameter of the image in the protocol [GX2] is equal to 1.65, the Effective Dose for the first protocol has lower value at 18%. Pka values reveal very similar results between the two protocols, although, common sense leads to the interpretation that imaging protocols with field of view (Fov) of large diameters imply high values of effective dose when compared to small diameters. However, in this particular case, this is not true due to the asymmetrical beam technology. Conclude that for the cases where the scanner uses asymmetric beam to obtain images with large diameters that cover the entire face there are advantages from the point of view of reducing the exposure of patients with respect to the use of symmetrical beam and / or to Fov images with a smaller diameter. (Author)

  2. Assessment of protocols in cone beam CT with symmetric and asymmetric beam using effective dose and P{sub ka}

    Energy Technology Data Exchange (ETDEWEB)

    Batista, W. O.; Linhares de O, M. V. [Instituto Federal da Bahia, Rua Emidio dos Santos s/n, Barbalho, Salvador, 40301015 Bahia (Brazil); Soares, M. R.; Maia, A. F. [Universidade Federal de Sergipe, Departamento de Fisica, Cidade Universitaria Prof. Jose Aloisio de Campos, Marechal Rondon s/n, Jardim Rosa Elze, 49-100000 Sao Cristovao, Sergipe (Brazil); Caldas, L. V. E., E-mail: wilsonottobatista@gmail.com [Instituto de Pesquisas Energeticas e Nucleares / CNEN, Av. Lineu Prestes 2242, Cidade Universitaria, 05508-000 Sao Paulo (Brazil)

    2014-08-15

    The cone beam CT is an emerging technology in dental radiology with significant differences the point of view of design technology between the various manufacturers on the world market. This study aims to evaluate and compare protocols with similar purposes in a cone beam CT scanner using TLDs and air kerma - area product (P{sub ka}) as kerma index. Measurements were performed on two protocols used to obtain the image the maxilla-mandible in equipment Gendex GXCB 500: Protocol [GX1] extended diameter and asymmetric beam (14 cm x 8.5 cm - maxilla / mandible) and protocol [GX2] symmetrical beam (8.5 cm x 8.5 cm - maxillary / mandible). Was used LiF dosimeters (TLD 100) inserted into a female anthropomorphic phantom manufactured by Radiology Support Devices. For all protocols evaluated the value of P{sub ka} using a meter Diamentor E2 and PTW system Radcal Rapidose. The results obtained for Effective Dose / P{sub ka} these measurements were separated by protocol image. Protocol [GX1]: 44.5 μSv/478 mGy cm{sup 2}; protocol [GX2]: 54.8 μSv/507 mGy cm{sup 2}. These values indicate that the relationship between the diameter of the image acquired in the protocol [GX1] and the diameter of the image in the protocol [GX2] is equal to 1.65, the Effective Dose for the first protocol has lower value at 18%. P{sub ka} values reveal very similar results between the two protocols, although, common sense leads to the interpretation that imaging protocols with field of view (Fov) of large diameters imply high values of effective dose when compared to small diameters. However, in this particular case, this is not true due to the asymmetrical beam technology. Conclude that for the cases where the scanner uses asymmetric beam to obtain images with large diameters that cover the entire face there are advantages from the point of view of reducing the exposure of patients with respect to the use of symmetrical beam and / or to Fov images with a smaller diameter. (Author)

  3. Exploring perception-action relations in music production: The asymmetric effect of tonal class.

    Science.gov (United States)

    Jebb, Andrew T; Pfordresher, Peter Q

    2016-05-01

    When playing musical passages, performers integrate the pitch content of auditory feedback with current action plans. However, this process depends on the degree to which the musical structure of the feedback melody is perceived as similar to the structure of what is planned. Four experiments reported here explored the relationship between the tonal class of planned melodies (tonal or atonal) and the sequence of events formed by auditory feedback. Participants produced short melodies from memory that were either tonal (Experiments 1 and 3) or atonal (Experiments 2 and 4). Auditory feedback matched the planned melody with respect to contour but could vary in tonal class. The results showed that when participants planned a tonal melody, atonal feedback was treated as unrelated to the planned sequence. However, when planning an atonal melody, tonal feedback was still treated as similar to the planned sequence. This asymmetric similarity mirrors findings found within the music perception literature and implies that schematic musical knowledge is highly active in determining perception-action relations during music performance. PMID:26594878

  4. Military leadership with an operational effect in asymmetric operations - A new military leadership training concept in a new world

    DEFF Research Database (Denmark)

    Barfod, Jakob Rømer

    2015-01-01

    . Suddenly, it was extremely important that the Danish Defence transformed to a more expeditionary force capable of conducting asymmetric operations in different environments far away from Denmark. This is not done overnight but demands a new situational awareness in proportion to the need for leadership....... As tactics, doctrines, technologies and procedures had to be developed and changed, there was also a need for developing the approach to leadership. Suddenly the challenges in the operations were not only IEDs, ambushes, shootings and deprivation of families, but also leadership challenges in military staffs...... and units, which in many cases acted and commanded based on a mindset of linear and symmetric warfare with great emphasis on analysis of primarily cause and effect. On that basis, the Danish Defence around mid-2000 developed a new operational leadership concept with a changed and different leadership focus...

  5. Carrier envelope phase effect on the spatial distribution of high-order harmonic generation in asymmetric molecule

    Science.gov (United States)

    Jun, Zhang; Hai-Feng, Liu; Xue-Fei, Pan; Hui, Du; Jing, Guo; Xue-Shen, Liu

    2016-05-01

    The spatial distribution in high-order harmonic generation (HHG) from the asymmetric diatomic molecule HeH2+ is investigated by numerically solving the non-Born–Oppenheimer time-dependent Schrödinger equation (TDSE). The spatial distribution of the HHG spectra shows that there is little contribution in HHG around the geometric center of two nuclei (z = 1.17 a.u.) and the equilibrium internuclear position of the H nucleus (z = 3.11 a.u.). We demonstrate the carrier envelope phase (CEP) effect on the spatial distribution of HHG in a few-cycle laser pulse. The HHG process is investigated by the time evolution of the electronic density distribution. The time–frequency analysis of HHG from two nuclei in HeH2+ is presented to further explain the underlying physical mechanism. Project supported by the National Natural Science Foundation of China (Grant Nos. 11271158, 11574117, and 61575077).

  6. Cis-by-Trans regulatory divergence causes the asymmetric lethal effects of an ancestral hybrid incompatibility gene.

    Directory of Open Access Journals (Sweden)

    Shamoni Maheshwari

    Full Text Available The Dobzhansky and Muller (D-M model explains the evolution of hybrid incompatibility (HI through the interaction between lineage-specific derived alleles at two or more loci. In agreement with the expectation that HI results from functional divergence, many protein-coding genes that contribute to incompatibilities between species show signatures of adaptive evolution, including Lhr, which encodes a heterochromatin protein whose amino acid sequence has diverged extensively between Drosophila melanogaster and D. simulans by natural selection. The lethality of D. melanogaster/D. simulans F1 hybrid sons is rescued by removing D. simulans Lhr, but not D. melanogaster Lhr, suggesting that the lethal effect results from adaptive evolution in the D. simulans lineage. It has been proposed that adaptive protein divergence in Lhr reflects antagonistic coevolution with species-specific heterochromatin sequences and that defects in LHR protein localization cause hybrid lethality. Here we present surprising results that are inconsistent with this coding-sequence-based model. Using Lhr transgenes expressed under native conditions, we find no evidence that LHR localization differs between D. melanogaster and D. simulans, nor do we find evidence that it mislocalizes in their interspecific hybrids. Rather, we demonstrate that Lhr orthologs are differentially expressed in the hybrid background, with the levels of D. simulans Lhr double that of D. melanogaster Lhr. We further show that this asymmetric expression is caused by cis-by-trans regulatory divergence of Lhr. Therefore, the non-equivalent hybrid lethal effects of Lhr orthologs can be explained by asymmetric expression of a molecular function that is shared by both orthologs and thus was presumably inherited from the ancestral allele of Lhr. We present a model whereby hybrid lethality occurs by the interaction between evolutionarily ancestral and derived alleles.

  7. Asimetrik Bilgi ve Para Politikasının Etkinliği(Asymmetric Information And Effectiveness Of Monetary Policy

    Directory of Open Access Journals (Sweden)

    Özcan KARAHAN

    2006-01-01

    Full Text Available It has been indicated in the recent economic literature that the accountability of monetary policies is the most significant variable determining the effectiveness of applications. Accordingly, transparency in monetary policy becomes the most important factor for Central Banks. Thus, asymmetric distribution of information between Central Bank and other economic units becomes a significant problem requiring to be solved in order to reach the efficient monetary policy. From this starting point, the study aims to analyze the basic resource of asymmetric information problems. We deal with the asymmetric information between Central Bank and other economic units in the framework of three resources. These are the deficiencies of information concerning the aim of policy, the transmission mechanism of policy and the data sets realized in process of policy application. Also, we will evaluate the policies of Central Bank in Turkey, determining the solutions for problems indicated in this study, in the framework of strategy towards Inflation Targeting

  8. Effects of Slip Condition, Variable Viscosity and Inclined Magnetic Field on the Peristaltic Motion of a Non-Newtonian Fluid in an Inclined Asymmetric Channel

    Directory of Open Access Journals (Sweden)

    A. Afsar Khan

    2016-01-01

    Full Text Available The peristaltic motion of a third order fluid due to asymmetric waves propagating on the sidewalls of a inclined asymmetric channel is discussed. The key features of the problem includes longwavelength and low-Reynolds number assumptions. A mathematical analysis has been carried out to investigate the effect of slip condition, variable viscosity and magnetohydrodynamics (MHD. Followed by the nondimensionalization of the nonlinear governing equations along with the nonlinear boundary conditions, a perturbation analysis is made. For the validity of the approximate solution, a numerical solution is obtained using the iterative collocation technique.

  9. Behavioral profiles displayed by rats in an elevated asymmetric plus-maze: effects of diazepam

    Directory of Open Access Journals (Sweden)

    Ruarte M.B.

    1999-01-01

    Full Text Available When rats are exposed to unknown environments where novelty and fear-inducing characteristics are present (conflictive environments, some specific behaviors are induced and exploration is apparently modulated by fear. In our laboratory, a new type of plus-maze was designed as a model of conflictive exploration. The maze is composed of four arms with different geometrical characteristics, differing from each other by the presence or absence of walls. The degree of asymmetry was as follows: NW, no wall arm; SW, a single high wall present; HL, a low and a high wall present, and HH, two high walls present. The four arms were arranged at 90o angles and the apparatus was called the elevated asymmetric plus-maze (APM. The purpose of the present study was to assess the behavioral profile of rats exposed for a single time to the APM with or without treatment with benzodiazepine. Increasing doses of diazepam were injected intraperitoneally in several groups of male, 90-day-old Holtzman rats. Distilled water was injected in control animals. Thirty minutes after treatment all rats were exposed singly to a 5-min test in the APM. Diazepam induced a biphasic modification of exploration in the NW and SW arms. The increase in the exploration score was evident at low doses of diazepam (0.25-1.0 mg/kg body weight and the decrease in exploration was found with the higher doses of diazepam (2.0-3.0 mg/kg body weight. Non-exploratory behaviors (permanency were not affected by benzodiazepine treatment. In the HL arm, exploration was not modified but permanency was increased in a dose-dependent manner. In the HH arm, exploration and permanency were not affected. Results are compatible with the idea that exploration-processing mechanisms in conflictive environments are modulated by fear-processing mechanisms of the brain.

  10. Behavioral profiles displayed by rats in an elevated asymmetric plus-maze: effects of diazepam.

    Science.gov (United States)

    Ruarte, M B; Alvarez, E O

    1999-01-01

    When rats are exposed to unknown environments where novelty and fear-inducing characteristics are present (conflictive environments), some specific behaviors are induced and exploration is apparently modulated by fear. In our laboratory, a new type of plus-maze was designed as a model of conflictive exploration. The maze is composed of four arms with different geometrical characteristics, differing from each other by the presence or absence of walls. The degree of asymmetry was as follows: NW, no wall arm; SW, a single high wall present; HL, a low and a high wall present, and HH, two high walls present. The four arms were arranged at 90 degrees angles and the apparatus was called the elevated asymmetric plus-maze (APM). The purpose of the present study was to assess the behavioral profile of rats exposed for a single time to the APM with or without treatment with benzodiazepine. Increasing doses of diazepam were injected intraperitoneally in several groups of male, 90-day-old Holtzman rats. Distilled water was injected in control animals. Thirty minutes after treatment all rats were exposed singly to a 5-min test in the APM. Diazepam induced a biphasic modification of exploration in the NW and SW arms. The increase in the exploration score was evident at low doses of diazepam (0.25-1.0 mg/kg body weight) and the decrease in exploration was found with the higher doses of diazepam (2.0-3.0 mg/kg body weight). Non-exploratory behaviors (permanency) were not affected by benzodiazepine treatment. In the HL arm, exploration was not modified but permanency was increased in a dose-dependent manner. In the HH arm, exploration and permanency were not affected. Results are compatible with the idea that exploration-processing mechanisms in conflictive environments are modulated by fear-processing mechanisms of the brain. PMID:10347776

  11. Effect of asymmetric hot rolling on texture, microstructure and magnetic properties in a non-grain oriented electrical steel

    Science.gov (United States)

    Chen, S.; Butler, J.; Melzer, S.

    2014-11-01

    In this study, both asymmetric hot rolling (AHR) and conventional hot rolling (CHR) were carried out to study the effect of the hot rolling conditions on the evolution of the texture and microstructure in a non-grain oriented (NGO) steel. The microstructure and texture in the subsequent processing stages were characterised and related to the final magnetic properties. The results show that AHR, compared with CHR, tends to homogenise texture through thickness of the hot band strips. AHR results in a higher fraction of the θ-fibre ({0 0 1}) and a lower fraction of the γ-fibre ({1 1 1}) in the hot band strips, which are favourable features in relation to the magnetic properties of the strip. However, the favourable features observed in hot rolled AHR strips are eliminated after cold rolling and annealing. Contrarily, the required θ-fibre is decreased and the unwanted γ-fibre is intensified in the AHR sheet after cold rolling and their strength is maintained in the subsequent process steps. On the other hand, AHR does not produce a discernible change in the grain size in the hot band annealed strip and in the final annealed sheet, except that the magnetic anisotropy in the AHR is improved after skin pass and extra annealing as the result of the redistribution of the texture components within the θ-fibre, no significant improvement of the magnetic properties as a direct consequence of the application of asymmetric hot rolling has been observed under the current AHR experimental conditions.

  12. Asymmetric Ashes

    Science.gov (United States)

    2006-11-01

    that oscillate in certain directions. Reflection or scattering of light favours certain orientations of the electric and magnetic fields over others. This is why polarising sunglasses can filter out the glint of sunlight reflected off a pond. When light scatters through the expanding debris of a supernova, it retains information about the orientation of the scattering layers. If the supernova is spherically symmetric, all orientations will be present equally and will average out, so there will be no net polarisation. If, however, the gas shell is not round, a slight net polarisation will be imprinted on the light. This is what broad-band polarimetry can accomplish. If additional spectral information is available ('spectro-polarimetry'), one can determine whether the asymmetry is in the continuum light or in some spectral lines. In the case of the Type Ia supernovae, the astronomers found that the continuum polarisation is very small so that the overall shape of the explosion is crudely spherical. But the much larger polarization in strongly blue-shifted spectral lines evidences the presence, in the outer regions, of fast moving clumps with peculiar chemical composition. "Our study reveals that explosions of Type Ia supernovae are really three-dimensional phenomena," says Dietrich Baade. "The outer regions of the blast cloud is asymmetric, with different materials found in 'clumps', while the inner regions are smooth." "This study was possible because polarimetry could unfold its full strength thanks to the light-collecting power of the Very Large Telescope and the very precise calibration of the FORS instrument," he adds. The research team first spotted this asymmetry in 2003, as part of the same observational campaign (ESO PR 23/03 and ESO PR Photo 26/05). The new, more extensive results show that the degree of polarisation and, hence, the asphericity, correlates with the intrinsic brightness of the explosion. The brighter the supernova, the smoother, or less clumpy

  13. Asymmetrical effects of mesophyll conductance on fundamental photosynthetic parameters and their relationships estimated from leaf gas exchange measurements

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Ying [University of Texas at Austin; Gu, Lianhong [ORNL

    2013-01-01

    Worldwide measurements of nearly 130 C3 species covering all major plant functional types are analyzed in conjunction with model simulations to determine the effects of mesophyll conductance (gm) on photosynthetic parameters and their relationships estimated from A/Ci curves. We find that an assumption of infinite gm results in up to 75% underestimation for maximum carboxylation rate Vcmax, 60% for maximum electron transport rate Jmax, and 40% for triose phosphate utilization rate Tu. Vcmax is most sensitive, Jmax is less sensitive, and Tu has the least sensitivity to the variation of gm. Due to this asymmetrical effect of gm, the ratios of Jmax to Vcmax, Tu to Vcmax, and Tu to Jmax are all overestimated. An infinite gm assumption also limits the freedom of variation of estimated parameters and artificially constrains parameter relationships to stronger shapes. These findings suggest the importance of quantifying gm for understanding in-situ photosynthetic machinery functioning. We show that a nonzero resistance to CO2 movement in chloroplasts has small effects on estimated parameters. A nonlinear function with gm as input is developed to convert the parameters estimated under an assumption of infinite gm to proper values. This function will facilitate gm representation in global carbon cycle models.

  14. Effect of the kinetic variables and postural stability between bilateral in lower limbs by the Oreum trekking exercise: asymmetric index.

    Science.gov (United States)

    Ryew, Che-Cheong; Hyun, Seung-Hyun

    2016-08-01

    This study aimed to analyze an effect of the kinetic variables and postural stability between bilateral in lower limbs by participation of Oreum trekking exercise program and subjects participated were composed of adult male and female subjects (n=14) of 20s. Experiment was performed with the drop landing which can evaluate postural stability and kinetic variables between bilateral in lower limbs. peak vertical force (PVF) value showed significant difference with the less in case of post than before participation of Oreum trekking exercise. Also PVF of bilateral in lower limbs did not showed significant difference, and too the effect of interaction. vertical stability index (VSI) and dynamic postural stability index (DPSI) showed significant difference with improvement of postural stability by Oreum trekking, but did not between bilateral in the limbs. Particularly the result of one-way analysis of variance due to VSI's effect of interaction, showed the more influence on the improvement of postural stability in left leg after participation of Oreum trekking exercise. When consideration the above, the analysis result on asymmetric index of bilateral in lower limbs showed more symmetric pattern in post than before participation of Oreum trekking exercise program. PMID:27656636

  15. Asymmetrical effects of mesophyll conductance on fundamental photosynthetic parameters and their relationships estimated from leaf gas exchange measurements.

    Science.gov (United States)

    Sun, Ying; Gu, Lianhong; Dickinson, Robert E; Pallardy, Stephen G; Baker, John; Cao, Yonghui; DaMatta, Fábio Murilo; Dong, Xuejun; Ellsworth, David; Van Goethem, Davina; Jensen, Anna M; Law, Beverly E; Loos, Rodolfo; Martins, Samuel C Vitor; Norby, Richard J; Warren, Jeffrey; Weston, David; Winter, Klaus

    2014-04-01

    Worldwide measurements of nearly 130 C3 species covering all major plant functional types are analysed in conjunction with model simulations to determine the effects of mesophyll conductance (g(m)) on photosynthetic parameters and their relationships estimated from A/Ci curves. We find that an assumption of infinite g(m) results in up to 75% underestimation for maximum carboxylation rate V(cmax), 60% for maximum electron transport rate J(max), and 40% for triose phosphate utilization rate T(u) . V(cmax) is most sensitive, J(max) is less sensitive, and T(u) has the least sensitivity to the variation of g(m). Because of this asymmetrical effect of g(m), the ratios of J(max) to V(cmax), T(u) to V(cmax) and T(u) to J(max) are all overestimated. An infinite g(m) assumption also limits the freedom of variation of estimated parameters and artificially constrains parameter relationships to stronger shapes. These findings suggest the importance of quantifying g(m) for understanding in situ photosynthetic machinery functioning. We show that a nonzero resistance to CO2 movement in chloroplasts has small effects on estimated parameters. A non-linear function with gm as input is developed to convert the parameters estimated under an assumption of infinite gm to proper values. This function will facilitate gm representation in global carbon cycle models. PMID:24117476

  16. Asymmetric impact of the physiological effect of carbon dioxide on hydrological responses to instantaneous negative and positive CO2 forcing

    Science.gov (United States)

    Abe, Manabu; Shiogama, Hideo; Yokohata, Tokuta; Emori, Seita; Nozawa, Toru

    2015-10-01

    We conducted sensitivity experiments using a coupled atmosphere-ocean general circulation model to examine the asymmetry between the hydrological responses to instantaneous positive and negative CO2 forcing and the impact of the CO2 physiological effects (CDPEs) on these responses. This study focuses on the fast response occurring on time scales shorter than 1 year after imposing CO2 forcing. Experiments investigating the CO2 physiological effect show that the fast response of precipitation to positive CO2 forcing is a decrease in the global and annual mean, whereas that of negative forcing is an increase the global and annual mean precipitation. The fast global precipitation response to negative forcing is stronger than the response to positive forcing. In contrast, the experiments without the CDPE reveal similar magnitudes of the fast global precipitation responses to negative and positive CO2 forcing. Significant differences in the magnitudes of the fast precipitation response due to the CDPE are found in tropical regions such as the Amazon Basin, the Maritime Continents, and tropical Africa, where C3-type plants are common. The stomatal conductance of plant leaves is decreased by both positive and negative CO2 forcing, which suppress the transpiration from the leaves. Consequently, the CDPE enhances the asymmetry of the fast precipitation responses to positive and negative CO2 forcing. The asymmetric impact of CDPE requires a careful evaluation of future hydrological changes which is constrained by paleoclimate evidence.

  17. Study of electro-optic effect in asymmetrically ramped AlInGaAs multiple quantum well structures

    International Nuclear Information System (INIS)

    We investigate the electro-optic properties of two oppositely ramped asymmetric quantum well structures in the AlInGaAs material system. The grading of the bandgap in the quantum wells has been achieved by changing the ratio of Al to Ga in the quaternary alloy during the epitaxial growth. The surface normal photo-response and the Fabry-Perot fringe shift in straight waveguides are compared for both structures as a function of applied voltage at 1550 nm for TE-polarized light. The measurements show a change in the refractive index due to a red shift of the excitonic resonances due to the quantum-confined Stark effect. The 10 quantum well structure with a ramp up of the bandgap in the growth direction leads to the figure of merit of the voltage for a π phase shift, Vπ by length, L, Vπ x L, of 6 as compared to 7 V . mm in the structure with a ramp in opposite direction. Further investigations show that the reduction in Vπ is due to increased absorption at high reverse bias which induces a non-linear phase change. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  18. Study of electro-optic effect in asymmetrically ramped AlInGaAs multiple quantum well structures

    Energy Technology Data Exchange (ETDEWEB)

    Sadiq, Muhammad Usman; Peters, Frank H.; Corbett, Brian [Tyndall National Institute, Lee Maltings, Cork (Ireland); Department of Physics, University College Cork, Cork (Ireland); O' Callaghan, James; Roycroft, Brendan; Thomas, Kevin; Pelucchi, Emanuele [Tyndall National Institute, Lee Maltings, Cork (Ireland)

    2016-04-15

    We investigate the electro-optic properties of two oppositely ramped asymmetric quantum well structures in the AlInGaAs material system. The grading of the bandgap in the quantum wells has been achieved by changing the ratio of Al to Ga in the quaternary alloy during the epitaxial growth. The surface normal photo-response and the Fabry-Perot fringe shift in straight waveguides are compared for both structures as a function of applied voltage at 1550 nm for TE-polarized light. The measurements show a change in the refractive index due to a red shift of the excitonic resonances due to the quantum-confined Stark effect. The 10 quantum well structure with a ramp up of the bandgap in the growth direction leads to the figure of merit of the voltage for a π phase shift, V{sub π} by length, L, V{sub π} x L, of 6 as compared to 7 V . mm in the structure with a ramp in opposite direction. Further investigations show that the reduction in V{sub π} is due to increased absorption at high reverse bias which induces a non-linear phase change. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  19. Three-Body Force Effects on EOS of Asymmetric Nuclear Matter and Proton Fraction in Neutron Star Matter

    Institute of Scientific and Technical Information of China (English)

    ZUO Wei; A.Lejeune; U.Lombardo; J.F.Mathiot

    2003-01-01

    The three-body force effects on the equation of state and its iso-spin dependence of asymmetric nuclearmatter and on the proton fraction in neutron star matter have been investigated within Brueckner-Hartree-Fock approachby using a microscopic three-body force. It is shown that, even in the presence of the three-body force, the empiricalparabolic law of the energy per nucleon vs. isospin asymmetry β= ( N - Z) /A is fulfilled in the whole asymmetry range0≤β≤1 and also up to high density. The three-body force provides a strong enhancement of symmetry energy at highdensity in agreement with relativistic approaches. It also shows that the three-body force leads to a much more rapidincreasing of symmetry energy with density in relatively high density region and to a much lower threshold density forthe direct URCA process to occur in a neutron star as compared to the predictions adopting only pure two-body force.

  20. On the role of asymmetric bargaining power in intermediate industry for existence of spiral effect

    OpenAIRE

    Prog, Kateryna

    2012-01-01

    This thesis proves the existence of the spiral effect in different scenarios with different modeling approaches. With a spiral effect is called the hypothesis that if, due to his bargaining power, one buyer has better procurement conditions than other buyers, he can use them to strengthen his market position in the sales market, which in turn improve his procurement situation, e.g. as he is in a position to negotiate additional quantity discounts. The analysis is divided into three blocks. In...

  1. [Development of new methods in asymmetric reactions and their applications].

    Science.gov (United States)

    Node, Manabu

    2002-01-01

    Several novel methods using chiral reagents and biocatalysts for asymmetric reactions are described. Among those reactions, asymmetric reduction via a novel tandem Michael addition/Meerwein-Ponndorf-Verley reduction of acyclic alpha,beta-unsaturated ketones using a chiral mercapto alcohol, asymmetric synthesis of allene-1,3-dicarboxylate via crystallization induced asymmetric transformation, and improved asymmetric nitroolefination of lactones and lactames at alpha-carbon using new chiral reagents were developed. In the reactions using biocatalysts, asymmetric dealkoxycarbonylation of bicyclic beta-keto diesters having sigma-symmetry with lipase or esterase to give optically active beta-keto esters, the asymmetric reduction of bicyclic 1,3-diketones having sigma-symmetry with Baker's yeast to give optically active keto alcohols, and the asymmetric aldol reaction of glycine with threonine aldolase were also developed. The above mentioned products were effectively utilized as chiral building blocks for the asymmetric synthesis of natural products and drugs.

  2. Relationship between protecitve effect of probucol on endothelial cells and asymmetrical dimethylarginine levels

    Institute of Scientific and Technical Information of China (English)

    Jun-linJIANG; Xiao-hongZHANG; Han-wuDENG; Yuan-JianLI

    2004-01-01

    AIM: To investigate the relationship between protective effect of probucol on endothelial cells and endogenous nitric oxide synthase inhibitor levels. METHODS: Endothelial cells were treated with oxidative-low density lipoprotein (ox-LDL) (100 rag/L) or lysophosphatidyl choline (LPC) (5 mg/L) for 48 h, and the release of lactate dehydrogenase (LDH), levels of nitric oxide (NO),

  3. Asymmetric magnetic proximity effect in a Pd/Co/Pd trilayer system

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dong-Ok; Song, Kyung Mee; Choi, Yongseong; Min, Byoung-Chul; Kim, Jae-Sung; Choi, Jun Woo; Lee, Dong Ryeol

    2016-05-06

    In spintronic devices consisting of ferromagnetic/nonmagnetic systems, the ferromagnet-induced magnetic moment in the adjacent nonmagnetic material significantly influences the spin transport properties. In this study, such magnetic proximity effect in a Pd/Co/Pd trilayer system is investigated by x-ray magnetic circular dichroism and x-ray resonant magnetic reflectivity, which enables magnetic characterizations with element and depth resolution. We observe that the total Pd magnetic moments induced at the top Co/Pd interface are significantly larger than the Pd moments at the bottom Pd/Co interface, whereas transmission electron microscopy and reflectivity analysis indicate the two interfaces are nearly identical structurally. Such asymmetry in magnetic proximity effects could be important for understanding spin transport characteristics in ferromagnetic/nonmagnetic systems and its potential application to spin devices.

  4. Investigation of asymmetric alcohol dehydrogenase (ADH) reduction of acetophenone derivatives: effect of charge density.

    Science.gov (United States)

    Naik, Hemantkumar G; Yeniad, Bahar; Koning, Cor E; Heise, Andreas

    2012-07-01

    In an effort to study the effect of substituent groups of the substrate on the alcohol dehydrogenase (ADH) reductions of aryl-alkyl ketones, several derivatives of acetophenone have been evaluated against ADHs from Lactobacillus brevis (LB) and Thermoanaerobacter sp. (T). Interestingly, ketones with non-demanding (neutral) para-substituents were reduced to secondary alcohols by these enzymes in enantiomerically pure form whereas those with demanding (ionizable) substituents could not be reduced. The effect of substrate size, their solubility in the reaction medium, electron donating and withdrawing properties of the ligand and also the electronic charge density distribution on the substrate molecules have been studied and discussed in detail. From the results, it is observed that the electronic charge distribution in the substrate molecules is influencing the orientation of the substrate in the active site of the enzyme and hence the ability to reduce the substrate.

  5. Effects of 3D Toroidally Asymmetric Magnetic Field on Tokamak Magnetic Surfaces

    Science.gov (United States)

    Lao, L. L.

    2005-10-01

    The effects of 3D error magnetic field on magnetic surfaces are investigated using the DIII-D internal coils (I-Coils). Slowly rotating n=1 traveling waves at 5 Hz and various amplitudes were applied to systematically perturb the edge surfaces by programming the I-Coil currents. The vertical separatrix location difference between EFIT magnetic reconstructions that assumes toroidal symmetry and Thomson scattering Te measurements responds in phase to the applied perturbed field. The oscillation amplitudes increase with the strength of the applied field but are much smaller than those expected from the applied field alone. The results indicate that plasma response is important. Various plasma response models based on results from the MHD codes MARS and GATO are being developed and compared to the experimental observations. To more accurately evaluate the effects of magnetic measurement errors, a new form of the magnetic uncertainty matrix is also being implemented into EFIT. Details will be presented.

  6. Asymmetric effects on the optical properties of double-quantum well systems

    Science.gov (United States)

    Silotia, Poonam; Batra, Kriti; Prasad, Vinod

    2014-02-01

    Linear, nonlinear, and total absorption coefficient and refractive index changes of double-quantum well (DQW) systems are studied theoretically in the presence of external static electric field applied along the growth direction. The analytical expression for the linear and nonlinear optical properties is obtained using density matrix method. Emphasis is laid on the effect of asymmetry in the shapes of DQW system on optical properties. Some interesting results are obtained and explained.

  7. Multistable syllables as enacted percepts: A source of an asymmetric bias in the verbal transformation effect

    OpenAIRE

    Sato, Marc; Schwartz, Jean-Luc; Abry, Christian; Cathiard, Marie-Agnes; Loevenbruck, Hélène

    2006-01-01

    Perceptual changes are experienced during rapid and continuous repetition of a speech form, leading to an auditory illusion known as the verbal transformation effect. Although verbal transformations are considered to reflect mainly the perceptual organization and interpretation of speech, the present study was designed to test whether or not speech production constraints may participate in the emergence of verbal representations. With this goal in mind, we examined whether variations in the a...

  8. Urban Core vs. Suburban Fringe: Asymmetrical Fiscal Effects of Tax and Expenditure Limitations in Metropolitan Areas

    OpenAIRE

    Eremin, Dmitry V

    2009-01-01

    This dissertation assesses the effects of tax and expenditure limitations (TELs) on principal items of revenue, largest components of expenditure and the levels of public debt of local governments serving urban cores and suburban fringes of the largest metropolitan areas in the US. The first part of the dissertation consists of 4 chapters. Chapter 1 examines the formal aspects of TELs; Chapter 2 explores historical evolution of fiscal limits between 1800 and 2009; Chapter 3 examines subs...

  9. Local, Organic, Conventional— Asymmetric Effects of Information and Taste on Label Preferences in an Experimental Auction

    OpenAIRE

    Costanigro, Marco; Kroll, Stephan; Thilmany, Dawn D.

    2012-01-01

    We endowed consumers with conventional apples and auctioned local, organic and organic-local apples to elicit consumers’ valuation and the response to two experimental treatments: scientific information and taste. For both labels, which participants valued as partial substitutes, positive WTP is conditional on distrusting the governmental food agencies. Information documenting the inconclusive scientific evidence in favor of organic and local production has little effect; while participants w...

  10. Are the Intraday Effects of Central Bank Intervention on Exchange Rate Spreads Asymmetric and State Dependent?

    DEFF Research Database (Denmark)

    Fatum, Rasmus; Pedersen, Jesper; Sørensen, Peter Norman

    This paper investigates the intraday effects of unannounced foreign exchange intervention on bid-ask exchange rate spreads using official intraday intervention data provided by the Danish central bank. Our starting point is a simple theoretical model of the bid-ask spread which we use to formulate...... exert a significant influence on the exchange rate spread, but in opposite directions: intervention purchases of the smaller currency, on average, reduce the spread while intervention sales, on average, increase the spread. We also show that intervention only affects the exchange rate spread when...

  11. Spin filter due to spin Hall effect with axially asymmetric potential

    Science.gov (United States)

    Yokoyama, Tomohiro; Eto, Mikio

    2010-02-01

    We examine a three-terminal spin filter including an artificial potential created by antidot, scanning tunnel microscope (STM) tip, etc., fabricated on semiconductor heterostructures with strong spin-orbit interaction. When the potential is attractive and its strength is properly tuned, the resonant scattering takes place, which enhances the extrinsic spin Hall effect. As a result, the efficiency of the spin filter can be more than 50% when the potential is axially symmetric. The efficiency becomes smaller when the symmetry is broken, but we still expect an efficient spin filter unless the degree of asymmetry is too large.

  12. The electrical asymmetry effect in geometrically asymmetric capacitive radio frequency plasmas

    International Nuclear Information System (INIS)

    The electrical asymmetry effect (EAE) allows an almost ideal separate control of the mean ion energy, i>, and flux, Γi, at the electrodes in capacitive radio frequency discharges with identical electrode areas driven at two consecutive harmonics with adjustable phase shift, θ. In such geometrically symmetric discharges, a DC self bias is generated as a function of θ. Consequently, i> can be controlled separately from Γi by adjusting the phase shift. Here, we systematically study the EAE in low pressure dual-frequency discharges with different electrode areas operated in argon at 13.56 MHz and 27.12 MHz by experiments, kinetic simulations, and analytical modeling. We find that the functional dependence of the DC self bias on θ is similar, but its absolute value is strongly affected by the electrode area ratio. Consequently, the ion energy distributions change and i> can be controlled by adjusting θ, but its control range is different at both electrodes and determined by the area ratio. Under distinct conditions, the geometric asymmetry can be compensated electrically. In contrast to geometrically symmetric discharges, we find the ratio of the maximum sheath voltages to remain constant as a function of θ at low pressures and Γi to depend on θ at the smaller electrode. These observations are understood by the model. Finally, we study the self-excitation of non-linear plasma series resonance oscillations and its effect on the electron heating.

  13. Error induced by the estimation of the corneal power and the effective lens position with a rotationally asymmetric refractive multifocal intraocular lens

    OpenAIRE

    David P. Piñero; Camps, Vicente J.; Ramón, María L.; Mateo, Verónica; Rafael J Pérez-Cambrodí

    2015-01-01

    AIM: To evaluate the prediction error in intraocular lens (IOL) power calculation for a rotationally asymmetric refractive multifocal IOL and the impact on this error of the optimization of the keratometric estimation of the corneal power and the prediction of the effective lens position (ELP). METHODS: Retrospective study including a total of 25 eyes of 13 patients (age, 50 to 83y) with previous cataract surgery with implantation of the Lentis Mplus LS-312 IOL (Oculentis GmbH, Germany). In a...

  14. Asymmetric activation of the anterior cerebral cortex in recipients of IRECA: preliminary evidence for the energetic effects of an intention-based treatment modality on human neurophysiology.

    OpenAIRE

    Pike, C.; Vernon, D.; Hald, L.

    2014-01-01

    Objectives: Neurophysiologic studies of mindfulness link the health benefits of meditation to activation of the left-anterior cerebral cortex. The similarity and functional importance of intention and attentional stance in meditative and biofield therapeutic practices suggest that modulation of recipient anterior asymmetric activation may mediate the energetic effects of intention-based biofield treatments as well. The aim of the current study was to test this hypothesis by using a treatment ...

  15. Interface dipole induced by asymmetric exchange effect in Mott-insulator/Mott-insulator heterojunction

    Institute of Scientific and Technical Information of China (English)

    Hao Lei; Wang Jua

    2008-01-01

    We study theoretically the interracial electronic property of a heterojunction made from two Mott insulators (MI)with different magnetic structures.By means of unrestricted Hartrce-Fock calculations in real space,we find that a charge dipole can form spontaneously near the interface of the MI/MI heterojunction.The magnitude of this charge dipole depends strongly on the magnetic states of both sides of the heterojunction.Combining with the result from an exactly solvable two-site toy model,we argue that the interface dipole arises from exchange effects as well as its asymmetry intrinsic to the heterojunction near the interface.Our study may shed light on the fabrication of ultrathin ferroelectric and magnetoelectric devices.

  16. Asymmetric synthesis and effect of absolute stereochemistry of YCZ-2013, a brassinosteroid biosynthesis inhibitor.

    Science.gov (United States)

    Oh, Keimei; Yamada, Kazuhiro; Yoshizawa, Yuko

    2013-12-15

    The four stereoisomers of 2RS,4RS-1-[[2-(2,4-dichlorophenyl)-4-(2-(2-propenyloxy)phenoxymethyl)-1,3-dioxolan-2-yl]methyl]-1H-1,2,4-triazole (YCZ-2013), a novel brassinosteroid biosynthesis inhibitor, were prepared. The diastereomers of 2RS,4R-5 and 2RS,4S-5 were prepared by using the corresponding optically pure R and S toluene-4-sulfonic acid 2,3-dihydroxypropyl ester (R-4,S-4). The enatiomerically and diastereomerically pure acetonide (5) was obtained by a method involving diastereoselective crystallisation of the tosylate salt, followed by re-equilibration with the mother liquor and chromatography. The optical purity of four target compounds (YCZ-2013) was confirmed by chiral high-performance liquid chromatography (HPLC) and NMR. The effects of these stereoisomers on Arabidopsis stem elongation indicated that the cis isomers of 2S,4R-YCZ-2013 and 2R,4S-YCZ-2013 exhibited potent inhibitory activity with IC50 values of approximately 24 ± 3 and 24 ± 2 nM, respectively. The IC50 values of the trans isomers of 2S,4S-YCZ-2013 and 2R,4R-YCZ-2013 are approximately 1510 ± 50 and 3900 ± 332 nM, respectively. Co-application of brassinolide (10nM), the most potent BR, and GA3 (1 μM) to Arabidopsis seedlings grown in the dark with 2R,4S-YCZ-2013 and 2S,4R-YCZ-2013 revealed that brassinolide recovered the induced dwarfism of Arabidopsis seedlings, whereas GA3 showed no effect. PMID:24269478

  17. Recursive graphical construction of feynman diagrams in straight phi(4) theory: asymmetric case and effective energy

    Science.gov (United States)

    Kastening

    2000-04-01

    The free energy of a multicomponent scalar field theory is considered as a functional W[G,J] of the free correlation function G and an external current J. It obeys nonlinear functional differential equations which are turned into recursion relations for the connected Green's functions in a loop expansion. These relations amount to a simple proof that W[G,J] generates only connected graphs and can be used to find all such graphs with their combinatoric weights. A Legendre transformation with respect to the external current converts the functional differential equations for the free energy into those for the effective energy Gamma[G,Phi], which is considered as a functional of the free correlation function G and the field expectation Phi. These equations are turned into recursion relations for the one-particle irreducible Green's functions. These relations amount to a simple proof that Gamma[G,J] generates only one-particle irreducible graphs and can be used to find all such graphs with their combinatoric weights. The techniques used also allow for a systematic investigation into resummations of classes of graphs. Examples are given for resumming one-loop and multiloop tadpoles, both through all orders of perturbation theory. Since the functional differential equations derived are nonperturbative, they constitute also a convenient starting point for other expansions than those in numbers of loops or powers of coupling constants. We work with general interactions through four powers in the field.

  18. Strong enhancement of Penning ionization for asymmetric atom pairs in cold Rydberg gases: the Tom and Jerry effect

    KAUST Repository

    Efimov, D K

    2016-05-18

    We consider Penning ionization of Rydberg atom pairs as an Auger-type process induced by the dipole-dipole interaction and employ semiclassical formulae for dipole transitions to calculate the autoionization width as a function of the principal quantum numbers, n d, n i, of both atoms. While for symmetric atom pairs with the well-known increase of the autoionization width with increasing n 0 is obtained, the result for asymmetric pairs is counterintuitive - for a fixed n i of the ionizing atom of the pair, the autoionization width strongly increases with decreasing n d of the de-excited atom. For H Rydberg atoms this increase reaches two orders of magnitude at the maximum of the n d dependence, and the same type of counterintuitive behavior is exhibited also by Na, Rb and Cs atoms. This is a purely quantum-mechanical effect, which points towards existence of optimal (we call them \\'Tom\\' and \\'Jerry\\' for \\'big\\' and \\'small\\') pairs of Rydberg atoms with respect to autoionization efficiency. Building on the model of population redistribution in cold Rydberg gases proposed in [1], we demonstrate that population evolution following the initial laser excitation of Rydberg atoms in state n 0 would eventually lead to the formation of such Tom-Jerry pairs with which feature autoionization widths that are enhanced by several orders of magnitude compared to that of two atoms in the initial laser-excited state n 0. We also show that in the high-density regime of cold Rydberg gas experiments the ionization rate of Tom-Jerry pairs can be substantially larger than the blackbody radiation-induced photoionization rate. © 2016 IOP Publishing Ltd.

  19. Strong enhancement of Penning ionization for asymmetric atom pairs in cold Rydberg gases: the Tom and Jerry effect

    Science.gov (United States)

    Efimov, D. K.; Miculis, K.; Bezuglov, N. N.; Ekers, A.

    2016-06-01

    We consider Penning ionization of Rydberg atom pairs as an Auger-type process induced by the dipole–dipole interaction and employ semiclassical formulae for dipole transitions to calculate the autoionization width as a function of the principal quantum numbers, n d , n i , of both atoms. While for symmetric atom pairs with {n}d={n}i={n}0 the well-known increase of the autoionization width with increasing n 0 is obtained, the result for asymmetric pairs is counterintuitive—for a fixed n i of the ionizing atom of the pair, the autoionization width strongly increases with decreasing n d of the de-excited atom. For H Rydberg atoms this increase reaches two orders of magnitude at the maximum of the n d dependence, and the same type of counterintuitive behavior is exhibited also by Na, Rb and Cs atoms. This is a purely quantum-mechanical effect, which points towards existence of optimal (we call them ‘Tom’ and ‘Jerry’ for ‘big’ and ‘small’) pairs of Rydberg atoms with respect to autoionization efficiency. Building on the model of population redistribution in cold Rydberg gases proposed in [1], we demonstrate that population evolution following the initial laser excitation of Rydberg atoms in state n 0 would eventually lead to the formation of such Tom–Jerry pairs with {n}i\\gt {n}0\\gt {n}d which feature autoionization widths that are enhanced by several orders of magnitude compared to that of two atoms in the initial laser-excited state n 0. We also show that in the high-density regime of cold Rydberg gas experiments the ionization rate of Tom–Jerry pairs can be substantially larger than the blackbody radiation-induced photoionization rate.

  20. Chiral dirhodium(II) carboxylates and carboxamidates as effective chemzymes in asymmetric synthesis of three-membered carbocycles.

    Science.gov (United States)

    Adly, Frady G; Ghanem, Ashraf

    2014-11-01

    In this review the recent advances in the utilization of two of the most important classes of dirhodium(II) paddlewheel complexes, dirhodium(II) carboxylates and carboxamidates, as chemzymes in inter- and intramolecular asymmetric cyclopropanation, as well as cyclopropenation reactions are discussed.

  1. Asymmetric magnetic bubble expansion under in-plane field in Pt/Co/Pt : Effect of interface engineering

    NARCIS (Netherlands)

    Lavrijsen, R.; Hartmann, D. M. F.; van den Brink, Ton; Yin, Y.; Barcones, B.; Duine, R. A.; Verheijen, M. A.; Swagten, H. J. M.; Koopmans, B.

    2015-01-01

    We analyze the impact of growth conditions on the asymmetric magnetic bubble expansion under an in-plane field in ultrathin Pt/Co/Pt films. Specifically, using sputter deposition, we vary the Ar pressure during the growth of the top Pt layer. This induces a large change in the interfacial structure

  2. Physical understanding of electron mobility in asymmetrically strained InGaAs-on-insulator metal-oxide-semiconductor field-effect transistors fabricated by lateral strain relaxation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, SangHyeon, E-mail: dadembyora@mosfet.t.u-tokyo.ac.jp, E-mail: sh-kim@kist.re.kr; Yokoyama, Masafumi; Ikku, Yuki; Nakane, Ryosho; Takenaka, Mitsuru; Takagi, Shinichi [Department of Electrical Engineering and Information Systems, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Ichikawa, Osamu; Osada, Takenori; Hata, Masahiko [Sumitomo Chemical Co. Ltd., 6 Kitahara, Tsukuba, Ibaraki 300-3294 (Japan)

    2014-03-17

    In this paper, we fabricated asymmetrically tensile-strained In{sub 0.53}Ga{sub 0.47}As-on-insulator (-OI) metal-oxide-semiconductor field-effect transistors (MOSFETs) using a lateral strain relaxation technique. A stripe-like line structure, fabricated in biaxially strained In{sub 0.53}Ga{sub 0.47}As-OI can lead to the lateral strain relaxation and asymmetric strain configuration in In{sub 0.53}Ga{sub 0.47}As-OI with the channel width of 100 nm. We have found that the effective mobility (μ{sub eff}) enhancement in In{sub 0.53}Ga{sub 0.47}As-OI MOSFETs with uniaxial-like asymmetric strain becomes smaller than that in In{sub 0.53}Ga{sub 0.47}As-OI MOSFETs with biaxial strain. We have clarified from a systematic analysis between the strain values and the μ{sub eff} characteristics that this mobility behavior can be understood by the change of the energy level of the conduction band minimum due to the lateral strain relaxation.

  3. Comparison of radial flow effects on partitions of multifragmenting sources formed in symmetric and asymmetric central collisions

    Directory of Open Access Journals (Sweden)

    Frankland J.D.

    2015-01-01

    Full Text Available The role of collective radial expansion in determining multifragmentation partition properties has previously been explored by comparing different-sized sources of the same excitation energy per nucleon formed by very different reaction mechanisms: excited quasi-projectiles from semi-peripheral Au+Au collisions and quasi-fused sources from central Xe+Sn collisions. New data has been obtained with INDRA on 181Ta+66Zn collisions in order to allow comparison of Xe+Sn data with quasi-fused systems having the same mass, charge and excitation energy per nucleon formed in mass-asymmetric reactions, for which a smaller initial compression is expected. Preliminary results confirm that, ceteris paribus, smaller radial flow leads to less fragments with more asymmetric partitions.

  4. The Effects of Introducing Advertising in Pay TV: A Model of Asymmetric Competition between Pay TV and Free TV

    OpenAIRE

    Helmut Dietl; Markus Lang; Panlang Lin

    2012-01-01

    This paper develops a theoretical model of asymmetric competition between a pay TV and a free TV broadcaster. Our model shows that the pay TV broadcaster has incentives to place advertising on its channel if the marginal return on advertising exceeds the viewers' disutility from advertising. In this case, however, the pay TV advertising level is always below the corresponding level on free TV. The pay TV advertising level can increase with a higher viewer disutility from advertising but the p...

  5. Examining asymmetric effects in the South African Philips curve: Evidence from logistic smooth transition regression (LSTR) models

    OpenAIRE

    Phiri, Andrew

    2015-01-01

    This study contributes to the foregoing literature by investigating asymmetric behaviour within the South African short-run Phillips curve for three versions of the Phillips curve specification namely; the New Classical Phillips curve, the New Keynesian Phillips curve and the Hybrid New Keynesian Phillips curve. To this end, we employ a logistic smooth transition regression (LSTR) econometric model to each of the aforementioned versions of the Phillips curve specifications for quarterly data ...

  6. Asymmetric dark matter in braneworld cosmology

    Energy Technology Data Exchange (ETDEWEB)

    Meehan, Michael T.; Whittingham, Ian B., E-mail: Michael.Meehan@my.jcu.edu.au, E-mail: Ian.Whittingham@jcu.edu.au [School of Engineering and Physical Sciences, James Cook University, Townsville, 4811 Australia (Australia)

    2014-06-01

    We investigate the effect of a braneworld expansion era on the relic density of asymmetric dark matter. We find that the enhanced expansion rate in the early universe predicted by the Randall-Sundrum II (RSII) model leads to earlier particle freeze-out and an enhanced relic density. This effect has been observed previously by Okada and Seto (2004) for symmetric dark matter models and here we extend their results to the case of asymmetric dark matter. We also discuss the enhanced asymmetric annihilation rate in the braneworld scenario and its implications for indirect detection experiments.

  7. On Combined Effects of Heat Transfer and Chemical Reaction for the Flow through an Asymmetric Channel with Orthogonally Deformable Porous Walls

    Directory of Open Access Journals (Sweden)

    Syed Tauseef Mohyud-Din

    2016-01-01

    Full Text Available The combined effects of heat transfer and chemical reaction are studied for the flow through a semi-infinite asymmetric channel with orthogonally deformable porous walls. The similarity transforms have been used to reduce the conservation laws to a corresponding system of nonlinear ordinary differential equations. The resulting equations are solved, both analytically and numerically, by using Homotopy Analysis Method (HAM and the fourth-order Runge-Kutta (RK-4 method, respectively. The convergence of the analytical solution is assured through the so-called total squared residual error analysis. The optimal values of auxiliary parameters are obtained by minimizing the total squared residual error.

  8. Asymmetric Epoxidation of Terminal Olefins with Binaphthyl Strapped Porphyrin Catalysts: π-π Stacking Interaction and Steric Effects on the Enantioselectivities

    Institute of Scientific and Technical Information of China (English)

    REN,Qizhi; WANG,Aiqing; LIU,Shuangyan; DING,XIaojian

    2009-01-01

    Two binaphthyl strapped porphyrins with similar chiral auxiliaries 1b and 2b were used as efficient catalysts for asymmetric epoxidation of both styrene derivatives and non-aromatic olefin substrates. Theoretical calculation of styrene approach to both catalysts has been performed. The subtle difference of the chiral cavities between two por-phyrins has been analyzed by 1H NMR. The π-π stacking interaction between aromatic substrates and catalysts might be one factor for the dramatic different enantioselectivities. Besides, the steric effect of the binaphthyl handle of lb and 2b also causes the high ee values for non-aromatic olefin epoxidations.

  9. Effects of surface residual species in SBA-16 on encapsulated chiral (1S,2S)-DPEN-RuCl2(TPP)2 in asymmetric hydrogenation of acetophenone

    Science.gov (United States)

    Shi, Xiufeng; Xing, Bin; Fan, Binbin; Xue, Zhaoteng; Li, Ruifeng

    2016-03-01

    The SBA-16 obtained by different routes of elimination of organic templates were used as the hosts for encapsulation of chiral Ru complex (1S,2S)-DPEN-RuCl2(TPP)2 ( 1) (DPEN = 1,2-diphenylethylene-diamine, TPP = triphenyl phosphine). The methods for removing templates had distinct effects on the amount of residual template in SBA-16, which made the SBA-16 with different surface and structure properties. 1 encapsulated in SBA-16 extracted with the mixture of pyridine and ethanol showed higher activity and enantioselectivity for acetophenone asymmetric hydrogenation.

  10. Regenerating a symmetry in asymmetric dark matter.

    Science.gov (United States)

    Buckley, Matthew R; Profumo, Stefano

    2012-01-01

    Asymmetric dark matter theories generically allow for mass terms that lead to particle-antiparticle mixing. Over the age of the Universe, dark matter can thus oscillate from a purely asymmetric configuration into a symmetric mix of particles and antiparticles, allowing for pair-annihilation processes. Additionally, requiring efficient depletion of the primordial thermal (symmetric) component generically entails large annihilation rates. We show that unless some symmetry completely forbids dark matter particle-antiparticle mixing, asymmetric dark matter is effectively ruled out for a large range of masses, for almost any oscillation time scale shorter than the age of the Universe. PMID:22304253

  11. Regenerating a symmetry in asymmetric dark matter.

    Science.gov (United States)

    Buckley, Matthew R; Profumo, Stefano

    2012-01-01

    Asymmetric dark matter theories generically allow for mass terms that lead to particle-antiparticle mixing. Over the age of the Universe, dark matter can thus oscillate from a purely asymmetric configuration into a symmetric mix of particles and antiparticles, allowing for pair-annihilation processes. Additionally, requiring efficient depletion of the primordial thermal (symmetric) component generically entails large annihilation rates. We show that unless some symmetry completely forbids dark matter particle-antiparticle mixing, asymmetric dark matter is effectively ruled out for a large range of masses, for almost any oscillation time scale shorter than the age of the Universe.

  12. Electrolyte and composition effects on the performances of asymmetric supercapacitors constructed with Mn3O4 nanoparticles-graphene nanocomposites

    Science.gov (United States)

    Xiao, Yuanhua; Cao, Yongbo; Gong, Yuyin; Zhang, Aiqin; Zhao, Jihong; Fang, Shaoming; Jia, Dianzeng; Li, Feng

    2014-01-01

    Nanocomposites of Mn3O4 nanoparticles and graphene (GR) nanosheets - Mn3O4@GR can be made by growing Mn3O4 nanoparticles directly on the surfaces of GR in solvothermal reactions. The asymmetric supercapacitors constructed with Mn3O4@GR as positive and activated carbon (AC) as negative electrodes, respectively, show highly enhanced performances in energy storage. It was found that the electrolytes employed in constructing electrodes of the devices can influence the performances of Mn3O4@GR supercapacitors dramatically. Compared to their energy density in KOH electrolyte, the devices exhibit improved charge storage performances in Na2SO4 electrolyte. Furthermore, the charge storage abilities of the devices are closely related to the amount of Mn3O4 nanoparticles loaded onto the surface of GR nanosheets. The performances of Mn3O4@GR//AC asymmetric supercapacitors can be optimized by carefully tailoring the composition of electrode materials and adjusting the electrolytes for making the devices.

  13. Asymmetric Base-Bleed Effect on Aerospike Plume-Induced Base-Heating Environment During Power-Pack Out

    Science.gov (United States)

    Wang, Ten-See; Droege, Alan; D'Agostino, Mark; Lee, Young-Ching; Williams, Robert

    2003-01-01

    A computational heat transfer design methodology was developed to study tbe dual-engine linear aerospike plume-induced base-heating environment during one power-pack out, in ascent flight. It includes a three-dimensional, finite volume, viscous, chemically reacting, and pressure-based computational fluid dynamics formulation, a special base-bleed boundary condition, and a three-dimensional, finite volume, and spectral-line-based weighted-sum-of-gray-gases absorption computational radiation heat transfer formulation. A separate radiation model was used for diagnostic purposes. The computational methodology was systematically benchmarked. in this study, near-base radiative heat fluxes were computed, and they compared well with those measured during static linear aerospike engine tests. The base-heating environment of 18 trajectory points secected from three power-pack out scenarios was computed. The computed asymmetric base-heating physics were analyzed. The power-pack out condition has the most impact on convective base heating when it happens early in flight. The soume of its impact comes from the asymmetric and reduced base bleed.

  14. Asymmetric Federalism in Russia: Cure or Poison?

    OpenAIRE

    Jorge Martinez-Vazquez

    2003-01-01

    In the early years of its existence, the Russian Federation adopted a system of differential treatment of its regions in order to cope with the great degree of diversity present in them. This paper examines the Russian Federation’s asymmetric federalism by evaluating the system’s role, significance and effects on the Federation’s development. The study incorporates a detailed description of the asymmetric federalism over time along with the benefits and costs incurred by its implementation. I...

  15. Terahertz metamaterial with asymmetric transmission

    CERN Document Server

    Singh, R; Menzel, C; Rockstuhl, C; Azad, A K; Cheville, R A; Lederer, F; Zhang, W; Zheludev, N I

    2009-01-01

    We show for the first time that a planar metamaterial, an array of coupled metal split-ring resonators with a unit cell lacking mirror symmetry, exhibits asymmetric transmission of terahertz radiation propagating through it in opposite directions. This intriguing effect, that is compatible with Lorentz reciprocity and time-reversal, depends on a directional difference in conversion efficiency of the incident circularly polarized wave into one of opposite handedness, that is only possible in lossy low-symmetry planar chiral metamaterials. We show that asymmetric transmission is linked to excitation of enantiomerically sensitive plasmons, these are induced charge-field excitations that depend on the mutual handedness of incident wave and metamaterial pattern. Various bands of positive, negative and zero phase and group velocities have been identified indicating the opportunity to develop polarization sensitive negative index and slow light media based on such metamaterials.

  16. Stable walking with asymmetric legs

    International Nuclear Information System (INIS)

    Asymmetric leg function is often an undesired side-effect in artificial legged systems and may reflect functional deficits or variations in the mechanical construction. It can also be found in legged locomotion in humans and animals such as after an accident or in specific gait patterns. So far, it is not clear to what extent differences in the leg function of contralateral limbs can be tolerated during walking or running. Here, we address this issue using a bipedal spring-mass model for simulating walking with compliant legs. With the help of the model, we show that considerable differences between contralateral legs can be tolerated and may even provide advantages to the robustness of the system dynamics. A better understanding of the mechanisms and potential benefits of asymmetric leg operation may help to guide the development of artificial limbs or the design novel therapeutic concepts and rehabilitation strategies.

  17. Asymmetric magnetoimpedance effect in CoFeSiB amorphous ribbons by combination of field and current annealing for sensor applications

    Science.gov (United States)

    Hajiali, Mohammadreza; Mohseni, S. Majid; Roozmeh, S. Ehsan; Moradi, Mehrdad

    2016-08-01

    The roles of applied magnetic field during the current annealing of Co68.15Fe4.35Si12.5B15 soft magnetic amorphous ribbons are studied. Samples heat treated by Joule heating effect in open air and simultaneously in the present of longitudinal external magnetic field showed asymmetric magnetoimpedance (AMI) behavior. The AMI profile can be related to the exchange bias interaction between the soft magnetic amorphous material and a harder magnetic crystalline phase formed on the surface of the ribbon. This effect stems from thermal effect, the transverse Oe field generated from the annealing current which is thickness dependent and the longitudinal external field. The single peak AMI with the field sensitivity of 101%/Oe for DC annealing current is achieved. Our results could address a simple way to achieve the AMI response toward developing high sensitive magnetic field sensors.

  18. Effects of Navier slip on unsteady flow of a reactive variable viscosity non- Newtonian fluid through a porous saturated medium with asymmetric convecti- ve boundary conditions

    Institute of Scientific and Technical Information of China (English)

    RUNDORA Lazarus; MAKINDE Oluwole Daniel

    2015-01-01

    A study on the effects of Navier slip, in conjunction with other flow parameters, on unsteady flow of reactive variable viscosity third-grade fluid through a porous saturated medium with asymmetric convective boundary conditions is presented. The channel walls are assumed to be subjected to asymmetric convective heat exchange with the ambient, and exothermic chemical reactions take place within the flow system. The heat exchange with the ambient obeys Newton’s law of cooling. The coupled equations, arising from the law of conservation of momentum and the first law of thermodynamics, then the derived system are non- dimensionalised and solved using a semi-implicit finite difference scheme. The lower wall slip parameter is observed to increase the fluid velocity profiles, whereas the upper wall slip parameter retards them because of backflow at the upper channel wall. Heat pro- duction in the fluid is seen to increase with the slip parameters. The wall shear stress increases with the slip parameters while the wall heat transfer rate is largely unaltered by the lower wall slip parameter but marginally increased by the upper wall slip parameter.

  19. Investigation of temperature-dependent asymmetric degradation behavior induced by hot carrier effect in oxygen ambiance in In–Ga–Zn-O thin film transistors

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Bo-Wei [Department of Photonics, National Sun Yat-Sen University, Kaohsiung, Taiwan (China); Chang, Ting-Chang [Department of Physics, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan (China); Advanced Optoelectronics Technology Center, National Cheng Kung University, Taiwan (China); Hung, Yu-Ju [Department of Photonics, National Sun Yat-Sen University, Kaohsiung, Taiwan (China); Hsieh, Tien-Yu [Department of Physics, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan (China); Tsai, Ming-Yen [Department of Photonics, National Sun Yat-Sen University, Kaohsiung, Taiwan (China); Liao, Po-Yung [Department of Physics, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan (China); Tsai, Wu-Wei; Chiang, Wen-Jen; Yan, Jing-Yi [Industrial Technology Research Institute, 195, Sec. 4, Chung Hsing Rd., Hsinchu, 31040, Taiwan (China)

    2014-12-01

    The effects of oxygen ambiance on electrical characteristic degradation phenomena in a-InGaZnO thin film transistor with different biases and temperatures are investigated. It can be found that oxygen is substantially adsorbed on the backchannel and results in device instabilities during positive gate bias stress. However, visible light irradiation is found to desorb the adsorbed oxygen ions and this verifies that oxygen dominates the degradation behavior. Moreover, comparing with that in vacuum, hot-carrier stress in oxygen ambiance leads to an extra potential barrier height near the drain side due to oxygen adsorption and causes asymmetric degradation. Furthermore, the asymmetric degradation behavior after hot-carrier stress in oxygen ambiance is suppressed at high temperature due to temperature-induced oxygen desorption or heat-induced holes injecting into the gate insulator. - Highlights: • Oxygen adsorbing will occur beneath the active layer under persistent positive gate bias. • Oxygen desorbing under illumination was verified from the recovery of transfer curves. • Additional barrier height is generated after hot-carrier stress because of oxygen adsorption. • The amount of hot-carrier degradation in oxygen ambience will decrease as temperature elevating.

  20. Microscopic approach to the nucleon-nucleon effective interaction and nucleon-nucleon scattering in symmetric and isospin-asymmetric nuclear matter

    CERN Document Server

    Sammarruca, Francesca

    2013-01-01

    After reviewing our microscopic approach to nuclear and neutron-rich matter, we focus on how nucleon-nucleon scattering is impacted by the presence of a dense hadronic medium, with special emphasis on the case where neutron and proton densities are different. We discuss in detail medium and isospin asymmetry effects on the total elastic cross section and the mean free path of a neutron or a proton in isospin-asymmetric nuclear matter. We point out that in-medium cross sections play an important role in heavy-ion simulations aimed at extracting constraints on the symmetry potential. We argue that medium and isospin dependence of microscopic cross sections are the results of a complex balance among various effects, and cannot be simulated with a simple phenomenological model.

  1. Thermal and velocity slip effects on the MHD peristaltic flow with carbon nanotubes in an asymmetric channel: application of radiation therapy

    Science.gov (United States)

    Akbar, Noreen Sher; Nadeem, S.; Khan, Zafar Hayat

    2014-10-01

    Peristaltic flow is used to study the flow and heat transfer of carbon nanotubes in an asymmetric channel with thermal and velocity slip effects. Two types of carbon nanotubes, namely, single- and multi-wall carbon nanotubes are utilized to see the analysis with water as base fluids. Empirical correlations are used for the thermo-physical properties of carbon nanotubes (CNTs) in terms of solid volume fraction of CNTs. The governing equations are simplified using long wavelength and low Reynolds number approximation. Exact solutions have been evaluated for velocity, pressure gradient, the solid volume fraction of CNTs and temperature profile. The effects of various flow parameters, i.e. Hatmann number M, the solid volume fraction of the nanoparticles ϕ, Grashof number G, velocity slip parameter β, thermal slip parameter γ and Prandtl number P r are presented graphically for both single- (SWCNT) and multi-wall carbon nanotubes (MWCNT).

  2. Effect of Lowering Asymmetric Dimethylarginine (ADMA on Vascular Pathology in Atherosclerotic ApoE-Deficient Mice with Reduced Renal Mass

    Directory of Open Access Journals (Sweden)

    Johannes Jacobi

    2014-03-01

    Full Text Available The purpose of the work was to study the impact of the endogenous nitric oxide synthase (NOS inhibitor asymmetric dimethylarginine (ADMA and its degrading enzyme, dimethylarginine dimethylaminohydrolase (DDAH1, on atherosclerosis in subtotally nephrectomized (SNX ApoE-deficient mice. Male DDAH1 transgenic mice (TG, n = 39 and C57Bl/6J wild-type littermates (WT, n = 27 with or without the deletion of the ApoE gene underwent SNX at the age of eight weeks. Animals were sacrificed at 12 months of age, and blood chemistry, as well as the extent of atherosclerosis within the entire aorta were analyzed. Sham treated (no renal mass reduction ApoE-competent DDAH1 transgenic and wild-type littermates (n = 11 served as a control group. Overexpression of DDAH1 was associated with significantly lower ADMA levels in all treatment groups. Surprisingly, SNX mice did not exhibit higher ADMA levels compared to sham treated control mice. Furthermore, the degree of atherosclerosis in ApoE-deficient mice with SNX was similar in mice with or without overexpression of DDAH1. Overexpression of the ADMA degrading enzyme, DDAH1, did not ameliorate atherosclerosis in ApoE-deficient SNX mice. Furthermore, SNX in mice had no impact on ADMA levels, suggesting a minor role of this molecule in chronic kidney disease (CKD in this mouse model.

  3. Asymmetrical international attitudes

    NARCIS (Netherlands)

    Van Oudenhoven, JP; Askevis-Leherpeux, F; Hannover, B; Jaarsma, R; Dardenne, B

    2002-01-01

    In general, attitudes towards nations have a fair amount of reciprocity: nations either like each other are relatively indifferent to each other or dislike each other Sometimes, however international attitudes are asymmetrical. In this study, we use social identity theory in order to explain asymmet

  4. An asymmetric Kadison's inequality

    CERN Document Server

    Bourin, Jean-Christophe

    2010-01-01

    Some inequalities for positive linear maps on matrix algebras are given, especially asymmetric extensions of Kadison's inequality and several operator versions of Chebyshev's inequality. We also discuss well-known results around the matrix geometric mean and connect it with complex interpolation.

  5. Explicit Compact Surface-Potential and Drain-Current Models for Generic Asymmetric Double-Gate Metal-Oxide-Semiconductor Field-Effect Transistors

    Science.gov (United States)

    Zhu, Zhaomin; Zhou, Xing; Chandrasekaran, Karthik; Rustagi, Subhash C.; See, Guan Huei

    2007-04-01

    In this paper, explicit surface potentials for undoped asymmetric-double-gate (a-DG) metal-oxide-semiconductor field-effect transistors (MOSFETs) suitable for compact model development are presented for the first time. The model is physically derived from Poisson’s equation in each region of operation and adopted in a unified regional approach. The proposed model is physically scalable with oxide/channel thicknesses and has been verified with generic implicit solutions for independent gate biases as well as for different gate/oxide materials. The model is extendable to silicon-on-insulator (SOI) and symmetric-DG (s-DG) MOSFETs. Finally, a continuous, explicit drain-current equation has been derived on the basis of the developed explicit surface-potential solutions.

  6. Effect of asymmetrical double-pockets and gate-drain underlap on Schottky barrier tunneling FET: Ambipolar conduction vs. high frequency performance

    Science.gov (United States)

    Shaker, Ahmed; Ossaimee, Mahmoud; Zekry, A.

    2016-08-01

    In this paper, a proposed structure based on asymmetrical double pockets SB-TFET with gate-drain underlap is presented. 2D extensive modeling and simulation, using Silvaco TCAD, were carried out to study the effect of both underlap length and pockets' doping on the transistor performance. It was found that the underlap from the drain side suppresses the ambipolar conduction and doesn't enhance the high-frequency characteristics. The enhancement of the high-frequency characteristics could be realized by increasing the doping of the drain pocket over the doping of the source pocket. An optimum choice was found which gives the conditions of minimum ambipolar conduction, maximum ON current and maximum cut-off frequency. These enhancements render the device more competitive as a nanometer transistor.

  7. Nuclear matter effects on $J/\\psi$ production in asymmetric Cu+Au collisions at $\\sqrt{s_{_{NN}}}$ = 200 GeV

    CERN Document Server

    Aidala, C; Akiba, Y; Akimoto, R; Alexander, J; Aoki, K; Apadula, N; Asano, H; Atomssa, E T; Awes, T C; Azmoun, B; Babintsev, V; Bai, M; Bai, X; Bannier, B; Barish, K N; Bathe, S; Baublis, V; Baumann, C; Baumgart, S; Bazilevsky, A; Beaumier, M; Belmont, R; Berdnikov, A; Berdnikov, Y; Bing, X; Black, D; Blau, D S; Bok, J; Boyle, K; Brooks, M L; Bryslawskyj, J; Buesching, H; Bumazhnov, V; Butsyk, S; Campbell, S; Chen, C -H; Chi, C Y; Chiu, M; Choi, I J; Choi, J B; Choi, S; Christiansen, P; Chujo, T; Cianciolo, V; Cole, B A; Cronin, N; Crossette, N; Csanád, M; Csörgő, T; Datta, A; Daugherity, M S; David, G; Dehmelt, K; Denisov, A; Deshpande, A; Desmond, E J; Ding, L; Do, J H; Drapier, O; Drees, A; Drees, K A; Durham, J M; Durum, A; D'Orazio, L; Engelmore, T; Enokizono, A; Esumi, S; Eyser, K O; Fadem, B; Fields, D E; Finger, M; Finger,, M; Fleuret, F; Fokin, S L; Frantz, J E; Franz, A; Frawley, A D; Fukao, Y; Gainey, K; Gal, C; Garg, P; Garishvili, A; Garishvili, I; Giordano, F; Glenn, A; Gong, X; Gonin, M; Goto, Y; de Cassagnac, R Granier; Grau, N; Greene, S V; Perdekamp, M Grosse; Gu, Y; Gunji, T; Guragain, H; Haggerty, J S; Hahn, K I; Hamagaki, H; Hanks, J; Hashimoto, K; Hayano, R; He, X; Hemmick, T K; Hester, T; Hill, J C; Hollis, R S; Homma, K; Hong, B; Hoshino, T; Huang, J; Huang, S; Ichihara, T; Ikeda, Y; Imai, K; Imazu, Y; Inaba, M; Iordanova, A; Isenhower, D; Isinhue, A; Ivanishchev, D; Jacak, B V; Jeon, S J; Jezghani, M; Jia, J; Jiang, X; Johnson, B M; Joo, K S; Jouan, D; Jumper, D S; Kamin, J; Kanda, S; Kang, B H; Kang, J H; Kang, J S; Kapustinsky, J; Kawall, D; Kazantsev, A V; Key, J A; Khachatryan, V; Khandai, P K; Khanzadeev, A; Kijima, K M; Kim, C; Kim, D J; Kim, E -J; Kim, Y -J; Kim, Y K; Kistenev, E; Klatsky, J; Kleinjan, D; Kline, P; Koblesky, T; Kofarago, M; Komkov, B; Koster, J; Kotchetkov, D; Kotov, D; Krizek, F; Kurita, K; Kurosawa, M; Kwon, Y; Lacey, R; Lai, Y S; Lajoie, J G; Lebedev, A; Lee, D M; Lee, G H; Lee, J; Lee, K B; Lee, K S; Lee, S H; Leitch, M J; Leitgab, M; Lewis, B; Li, X; Lim, S H; Liu, M X; Lynch, D; Maguire, C F; Makdisi, Y I; Makek, M; Manion, A; Manko, V I; Mannel, E; Maruyama, T; McCumber, M; McGaughey, P L; McGlinchey, D; McKinney, C; Meles, A; Mendoza, M; Meredith, B; Miake, Y; Mibe, T; Mignerey, A C; Milov, A; Mishra, D K; Mitchell, J T; Miyasaka, S; Mizuno, S; Mohanty, A K; Morrison, D P; Moskowitz, M; Moukhanova, T V; Murakami, T; Murata, J; Nagae, T; Nagamiya, S; Nagle, J L; Nagy, M I; Nakagawa, I; Nakamiya, Y; Nakamura, K R; Nakamura, T; Nakano, K; Nattrass, C; Netrakanti, P K; Nihashi, M; Niida, T; Nouicer, R; Novak, T; Novitzky, N; Nyanin, A S; O'Brien, E; Ogilvie, C A; Oide, H; Okada, K; Oskarsson, A; Ozawa, K; Pak, R; Pantuev, V; Papavassiliou, V; Park, I H; Park, S; Park, S K; Pate, S F; Patel, L; Peng, J -C; Perepelitsa, D; Perera, G D N; Peressounko, D Yu; Perry, J; Petti, R; Pinkenburg, C; Pisani, R P; Purschke, M L; Qu, H; Rak, J; Ravinovich, I; Read, K F; Reynolds, D; Riabov, V; Riabov, Y; Richardson, E; Riveli, N; Roach, D; Rolnick, S D; Rosati, M; Ryu, M S; Sahlmueller, B; Saito, N; Sakaguchi, T; Sako, H; Samsonov, V; Sarsour, M; Sato, S; Sawada, S; Sedgwick, K; Seele, J; Seidl, R; Sekiguchi, Y; Sen, A; Seto, R; Sett, P; Sharma, D; Shaver, A; Shein, I; Shibata, T -A; Shigaki, K; Shimomura, M; Shoji, K; Shukla, P; Sickles, A; Silva, C L; Silvermyr, D; Singh, B K; Singh, C P; Singh, V; Skolnik, M; Slunečka, M; Solano, S; Soltz, R A; Sondheim, W E; Sorensen, S P; Soumya, M; Sourikova, I V; Stankus, P W; Steinberg, P; Stenlund, E; Stepanov, M; Ster, A; Stoll, S P; Stone, M R; Sugitate, T; Sukhanov, A; Sun, J; Takahara, A; Taketani, A; Tanida, K; Tannenbaum, M J; Tarafdar, S; Taranenko, A; Tennant, E; Timilsina, A; Todoroki, T; Tomášek, M; Torii, H; Towell, R S; Tserruya, I; van Hecke, H W; Vargyas, M; Vazquez-Zambrano, E; Veicht, A; Velkovska, J; Vértesi, R; Virius, M; Vrba, V; Vznuzdaev, E; Wang, X R; Watanabe, D; Watanabe, K; Watanabe, Y; Watanabe, Y S; Wei, F; Whitaker, S; Wolin, S; Woody, C L; Wysocki, M; Yamaguchi, Y L; Yanovich, A; Yokkaichi, S; Yoon, I; You, Z; Younus, I; Yushmanov, I E; Zajc, W A; Zelenski, A; Zhou, S

    2014-01-01

    We report on $J/\\psi$ production from asymmetric Cu+Au heavy-ion collisions at $\\sqrt{s_{_{NN}}}$=200 GeV at the Relativistic Heavy Ion Collider at both forward (Cu-going direction) and backward (Au-going direction) rapidities. The nuclear modification of $J/\\psi$ yields in Cu$+$Au collisions in the Au-going direction is found to be comparable to that in Au$+$Au collisions when plotted as a function of the number of participating nucleons. In the Cu-going direction, $J/\\psi$ production shows a stronger suppression. This difference is comparable in magnitude and has the same sign as the difference expected from shadowing effects due to stronger low-$x$ gluon suppression in the larger Au nucleus. The relative suppression is opposite to that expected from hot nuclear matter dissociation, since a higher energy density is expected in the Au-going direction.

  8. Asymmetric reactions in continuous flow

    Directory of Open Access Journals (Sweden)

    Xiao Yin Mak

    2009-04-01

    Full Text Available An overview of asymmetric synthesis in continuous flow and microreactors is presented in this review. Applications of homogeneous and heterogeneous asymmetric catalysis as well as biocatalysis in flow are discussed.

  9. Asymmetric catalysis with helical polymers

    NARCIS (Netherlands)

    Megens, Rik P.; Roelfes, Gerard

    2011-01-01

    Inspired by nature, the use of helical biopolymer catalysts has emerged over the last years as a new approach to asymmetric catalysis. In this Concept article the various approaches and designs and their application in asymmetric catalysis will be discussed.

  10. Spontaneous baryogenesis from asymmetric inflaton

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Fuminobu [Tohoku Univ., Sendai (Japan). Dept. of Physics; Tokyo Univ., Chiba (Japan). Kavli IPMU (WPI), UTIAS; Yamada, Masaki [Tokyo Univ., Chiba (Japan). Kavli IPMU (WPI), UTIAS; Tokyo Univ., Chiba (Japan). Inst. for Cosmic Ray Research; DESY Hamburg (Germany)

    2015-10-15

    We propose a variant scenario of spontaneous baryogenesis from asymmetric inflaton based on current-current interactions between the inflaton and matter fields with a non-zero B-L charge. When the inflaton starts to oscillate around the minimum after inflation, it may lead to excitation of a CP-odd component, which induces an effective chemical potential for the B-L number through the current-current interactions. We study concrete inflation models and show that the spontaneous baryogenesis scenario can be naturally implemented in the chaotic inflation in supergravity.

  11. Asymmetric transmission: a generic property of lossy periodic interfaces

    CERN Document Server

    Plum, E; Zheludev, N I

    2010-01-01

    Asymmetric transmission of circularly polarized waves is a well-established property of lossy, anisotropic, two-dimensionally chiral patterns. Here we show that asymmetric transmission can be observed for oblique incidence onto any lossy periodically structured plane. Our results greatly expand the range of natural and artificial materials in which directionally asymmetric transmission can be expected making it a cornerstone electromagnetic effect rather than a curiosity of planar chiral metamaterials. Prime candidates for asymmetric transmission at oblique incidence are rectangular arrays of plasmonic spheres or semiconductor quantum dots, lossy double-periodic gratings and planar metamaterial structures.

  12. Asymmetric information and economics

    Science.gov (United States)

    Frieden, B. Roy; Hawkins, Raymond J.

    2010-01-01

    We present an expression of the economic concept of asymmetric information with which it is possible to derive the dynamical laws of an economy. To illustrate the utility of this approach we show how the assumption of optimal information flow leads to a general class of investment strategies including the well-known Q theory of Tobin. Novel consequences of this formalism include a natural definition of market efficiency and an uncertainty principle relating capital stock and investment flow.

  13. Asymmetric Organocatalytic Cycloadditions

    DEFF Research Database (Denmark)

    Mose, Rasmus

    2016-01-01

    were pioneered by Otto Paul Hermann Diels and Kurt Alder who discovered what later became known as the Diels Alder reaction. The Diels Alder reaction is a [4+2] cycloaddition in which a π4 component reacts with a π2 component via a cyclic transition state to generate a 6 membered ring. This reaction...... reactions constitute the first organocatalytic asymmetric higher order cycloadditions and a rational for the periselectivity and stereoselectivity is provided based on experimental and computational investigations....

  14. Excitons in asymmetric quantum wells

    Science.gov (United States)

    Grigoryev, P. S.; Kurdyubov, A. S.; Kuznetsova, M. S.; Ignatiev, I. V.; Efimov, Yu. P.; Eliseev, S. A.; Petrov, V. V.; Lovtcius, V. A.; Shapochkin, P. Yu.

    2016-09-01

    Resonance dielectric response of excitons is studied for the high-quality InGaAs/GaAs heterostructures with wide asymmetric quantum wells (QWs). To highlight effects of the QW asymmetry, we have grown and studied several heterostructures with nominally square QWs as well as with triangle-like QWs. Several quantum confined exciton states are experimentally observed as narrow exciton resonances. A standard approach for the phenomenological analysis of the profiles is generalized by introducing different phase shifts for the light waves reflected from the QWs at different exciton resonances. Good agreement of the phenomenological fit to the experimentally observed exciton spectra for high-quality structures allowed us to reliably obtain parameters of the exciton resonances: the exciton transition energies, the radiative broadenings, and the phase shifts. A direct numerical solution of the Schrödinger equation for the heavy-hole excitons in asymmetric QWs is used for microscopic modeling of the exciton resonances. Remarkable agreement with the experiment is achieved when the effect of indium segregation is taken into account. The segregation results in a modification of the potential profile, in particular, in an asymmetry of the nominally square QWs.

  15. Linear and nonlinear optical properties in an asymmetric double quantum well under intense laser field: Effects of applied electric and magnetic fields

    Science.gov (United States)

    Yesilgul, U.; Al, E. B.; Martínez-Orozco, J. C.; Restrepo, R. L.; Mora-Ramos, M. E.; Duque, C. A.; Ungan, F.; Kasapoglu, E.

    2016-08-01

    In the present study, the effects of electric and magnetic fields on the linear and third-order nonlinear optical absorption coefficients and relative change of the refractive index in asymmetric GaAs/GaAlAs double quantum wells under intense laser fields are theoretically investigated. The electric field is oriented along the growth direction of the heterostructure while the magnetic field is taken in-plane. The intense laser field is linear polarization along the growth direction. Our calculations are made using the effective-mass approximation and the compact density-matrix approach. Intense laser effects on the system are investigated with the use of the Floquet method with the consequent change in the confinement potential of heterostructures. Our results show that the increase of the electric and magnetic fields blue-shifts the peak positions of the total absorption coefficient and of the total refractive index while the increase of the intense laser field firstly blue-shifts the peak positions and later results in their red-shifting.

  16. EFFECTS OF GEOMETRICAL STRUCTURE ON MICROWAVE AND OPTICAL PROPERTIES OF TRAVELING WAVE ELECTROABSORPTION MODULATORS BASED ON ASYMMETRIC COUPLED STRAINED QUANTUM WELLS ACTIVE LAYER

    Directory of Open Access Journals (Sweden)

    KAMBIZ ABEDI

    2011-08-01

    Full Text Available This paper presents the effects of geometrical structure on microwave and optical properties of traveling wave electroabsorption modulators (TWEAMs based on asymmetric intra-step-barrier coupled double strained quantum wells (AICD-SQW active layer. The AICD-SQW active layer structure has advantages such as very low insertion loss, zero chirp, large Stark shift and high extinction ratio in comparison with the intra-step quantum well (IQW structure. Firstly, the influences of the intrinsic (active layer thickness and width on effective optical index and confinement factor are analyzed. Furthermore, the effect of the intrinsic layer thickness on their transmission line microwave properties such as microwave index, microwave loss, andcharacteristic impedance are evaluated. The thickness and width of active layer are changed from 0 μm to 1.4 μm and 1 μm to 3 μm, respectively. Finally, the frequency response of TWEAM based on AICD-SQW active layer is calculated using circuit model.

  17. Probing the effect of dopants (donors) within InAs/InGaAs/InAlAs Asymmetric Heterostructure wafer by magneto-THz spectroscopy

    Science.gov (United States)

    Pakmehr, Mehdi; Heyn, Christian; Hansen, Wolfgang

    Probing the effect of impurities within semiconductor structures have been the topic of interest both from applied and scientific point of views. We studied the effect of dopants (donors) within InAs/InGaAs/InAlAs asymmetric heterostructure wafer by means of THz magneto-transmission (TR) spectroscopy, in conjunction with THz magneto-photoresponse (PR) spectroscopy. The sample wafer has been immersed in pumped liquid Helium at 1.6 K, while being exposed to sweeping magnetic field up to 10 Tesla, with THz laser beam (1.4 THz) being focused on sample by off-axis parabolic mirror. The transmitted beam was detected by silicon composite bolometer. Two broad absorption features other than sharp Cyclotron resonance (CR) absorption dip within magneto-TR signal attributed to 1s -->2P transition within donors of doped layer (InAlAs) in heterostructure. We plan to discuss the analysis of magneto-TR signal, in conjunction with Magneto-PR signals from Hall bar samples made from same type of wafer at same frequency to clarify how dopants could possibly alter these signals.

  18. Asymmetric conditional volatility in international stock markets

    Science.gov (United States)

    Ferreira, Nuno B.; Menezes, Rui; Mendes, Diana A.

    2007-08-01

    Recent studies show that a negative shock in stock prices will generate more volatility than a positive shock of similar magnitude. The aim of this paper is to appraise the hypothesis under which the conditional mean and the conditional variance of stock returns are asymmetric functions of past information. We compare the results for the Portuguese Stock Market Index PSI 20 with six other Stock Market Indices, namely the SP 500, FTSE 100, DAX 30, CAC 40, ASE 20, and IBEX 35. In order to assess asymmetric volatility we use autoregressive conditional heteroskedasticity specifications known as TARCH and EGARCH. We also test for asymmetry after controlling for the effect of macroeconomic factors on stock market returns using TAR and M-TAR specifications within a VAR framework. Our results show that the conditional variance is an asymmetric function of past innovations raising proportionately more during market declines, a phenomenon known as the leverage effect. However, when we control for the effect of changes in macroeconomic variables, we find no significant evidence of asymmetric behaviour of the stock market returns. There are some signs that the Portuguese Stock Market tends to show somewhat less market efficiency than other markets since the effect of the shocks appear to take a longer time to dissipate.

  19. Asymmetric synthesis v.4

    CERN Document Server

    Morrison, James

    1984-01-01

    Asymmetric Synthesis, Volume 4: The Chiral Carbon Pool and Chiral Sulfur, Nitrogen, Phosphorus, and Silicon Centers describes the practical methods of obtaining chiral fragments. Divided into five chapters, this book specifically examines initial chiral transmission and extension. The opening chapter describes the so-called chiral carbon pool, the readily available chiral carbon fragments used as building blocks in synthesis. This chapter also provides a list of 375 chiral building blocks, along with their commercial sources, approximate prices, and methods of synthesis. Schemes involving

  20. HIV replication, inflammation, and the effect of starting antiretroviral therapy on plasma asymmetric dimethylarginine, a novel marker of endothelial dysfunction

    DEFF Research Database (Denmark)

    Baker, Jason V; Neuhaus, Jacqueline; Duprez, Daniel;

    2012-01-01

    HIV infection is associated with premature development of cardiovascular disease. Understanding the effects of HIV replication on endothelial dysfunction and platelet activation may identify treatment targets to reduce cardiovascular disease risk.......HIV infection is associated with premature development of cardiovascular disease. Understanding the effects of HIV replication on endothelial dysfunction and platelet activation may identify treatment targets to reduce cardiovascular disease risk....

  1. Asymmetric quantum cloning machines

    International Nuclear Information System (INIS)

    A family of asymmetric cloning machines for quantum bits and N-dimensional quantum states is introduced. These machines produce two approximate copies of a single quantum state that emerge from two distinct channels. In particular, an asymmetric Pauli cloning machine is defined that makes two imperfect copies of a quantum bit, while the overall input-to-output operation for each copy is a Pauli channel. A no-cloning inequality is derived, characterizing the impossibility of copying imposed by quantum mechanics. If p and p' are the probabilities of the depolarizing channels associated with the two outputs, the domain in (√p,√p')-space located inside a particular ellipse representing close-to-perfect cloning is forbidden. This ellipse tends to a circle when copying an N-dimensional state with N→∞, which has a simple semi-classical interpretation. The symmetric Pauli cloning machines are then used to provide an upper bound on the quantum capacity of the Pauli channel of probabilities px, py and pz. The capacity is proven to be vanishing if (√px, √py, √pz) lies outside an ellipsoid whose pole coincides with the depolarizing channel that underlies the universal cloning machine. Finally, the tradeoff between the quality of the two copies is shown to result from a complementarity akin to Heisenberg uncertainty principle. (author)

  2. Asymmetric inclusion process

    Science.gov (United States)

    Reuveni, Shlomi; Eliazar, Iddo; Yechiali, Uri

    2011-10-01

    We introduce and explore the asymmetric inclusion process (ASIP), an exactly solvable bosonic counterpart of the fermionic asymmetric exclusion process (ASEP). In both processes, random events cause particles to propagate unidirectionally along a one-dimensional lattice of n sites. In the ASEP, particles are subject to exclusion interactions, whereas in the ASIP, particles are subject to inclusion interactions that coalesce them into inseparable clusters. We study the dynamics of the ASIP, derive evolution equations for the mean and probability generating function (PGF) of the sites’ occupancy vector, obtain explicit results for the above mean at steady state, and describe an iterative scheme for the computation of the PGF at steady state. We further obtain explicit results for the load distribution in steady state, with the load being the total number of particles present in all lattice sites. Finally, we address the problem of load optimization, and solve it under various criteria. The ASIP model establishes bridges between statistical physics and queueing theory as it represents a tandem array of queueing systems with (unlimited) batch service, and a tandem array of growth-collapse processes.

  3. Error induced by the estimation of the corneal power and the effective lens position with a rotationally asymmetric refractive multifocal intraocular lens

    Science.gov (United States)

    Piñero, David P.; Camps, Vicente J.; Ramón, María L.; Mateo, Verónica; Pérez-Cambrodí, Rafael J.

    2015-01-01

    AIM To evaluate the prediction error in intraocular lens (IOL) power calculation for a rotationally asymmetric refractive multifocal IOL and the impact on this error of the optimization of the keratometric estimation of the corneal power and the prediction of the effective lens position (ELP). METHODS Retrospective study including a total of 25 eyes of 13 patients (age, 50 to 83y) with previous cataract surgery with implantation of the Lentis Mplus LS-312 IOL (Oculentis GmbH, Germany). In all cases, an adjusted IOL power (PIOLadj) was calculated based on Gaussian optics using a variable keratometric index value (nkadj) for the estimation of the corneal power (Pkadj) and on a new value for ELP (ELPadj) obtained by multiple regression analysis. This PIOLadj was compared with the IOL power implanted (PIOLReal) and the value proposed by three conventional formulas (Haigis, Hoffer Q and Holladay I). RESULTS PIOLReal was not significantly different than PIOLadj and Holladay IOL power (P>0.05). In the Bland and Altman analysis, PIOLadj showed lower mean difference (-0.07 D) and limits of agreement (of 1.47 and -1.61 D) when compared to PIOLReal than the IOL power value obtained with the Holladay formula. Furthermore, ELPadj was significantly lower than ELP calculated with other conventional formulas (PLentis Mplus LS-312 can be optimized by minimizing the keratometric error and by estimating ELP using a mathematical expression dependent on anatomical factors. PMID:26085998

  4. A traffic-depended multi-buffer node architecture and an effective access technique under symmetric and asymmetric IP traffic scenarios for unslotted ring WDM MANs

    Science.gov (United States)

    Baziana, Peristera A.

    2016-09-01

    This study aims to put forward an extensive discussion about the increasing demand for available bandwidth to serve the multiple types of traffic in modern wavelength division multiplexing (WDM) metropolitan area networks (MANs). A traffic-depended multi-buffer node architecture in conjunction with an efficient asynchronous transmission WDM access (WDMA) protocol to serve the variable size Internet packets in ring MANs is proposed. The structure of the multi-buffer node architecture is determined by the probability distribution of each packet size category in the MAN traffic, providing storage and dropping events equity among the nodes. The adopted WDMA algorithm satisfies the requirement for high performance efficiency especially under high offered load, by taking care to optimally face the bandwidth fragmentation problem and to maximize the bandwidth exploitation, while it effectively avoids both the packets collisions over the wavelengths and the destination conflicts. Numerical results prove that the proposed network model achieves throughput improvement up to 334% as compared with the relative study of Pranggono and Elmirghani (2011). An analytical framework is developed for the protocol throughput predictions under both symmetric and asymmetric IP traffic scenarios. Also, the proposed protocol performance is thoroughly investigated through simulation results based on Poisson and self-similar traffic model statistics, for both traffic scenarios.

  5. Co(OH)2/RGO/NiO sandwich-structured nanotube arrays with special surface and synergistic effects as high-performance positive electrodes for asymmetric supercapacitors.

    Science.gov (United States)

    Xu, Han; Zhang, Chi; Zhou, Wen; Li, Gao-Ren

    2015-10-28

    High power density, high energy density and excellent cycling stability are the main requirements for high-performance supercapacitors (SCs) that will be widely used for portable consumer electronics and hybrid electric vehicles. Here we investigate novel types of hybrid Co(OH)2/reduced graphene oxide (RGO)/NiO sandwich-structured nanotube arrays (SNTAs) as positive electrodes for asymmetric supercapacitors (ASCs). The synthesized Co(OH)2/RGO/NiO SNTAs exhibit a significantly improved specific capacity (∼1470 F g(-1) at 5 mV s(-1)) and excellent cycling stability with ∼98% Csp retention after 10 000 cycles because of the fast transport and short diffusion paths for electroactive species, the high utilization rate of electrode materials, and special synergistic effects among Co(OH)2, RGO, and NiO. The high-performance ASCs are assembled using Co(OH)2/RGO/NiO SNTAs as positive electrodes and active carbon (AC) as negative electrodes, and they exhibit a high energy density (115 Wh kg(-1)), a high power density (27.5 kW kg(-1)) and an excellent cycling stability (less 5% Csp loss after 10 000 cycles). This study shows an important breakthrough in the design and fabrication of multi-walled hybrid nanotube arrays as positive electrodes for ASCs. PMID:26416358

  6. Probing the "additive effect" in the proline and proline hydroxamic acid catalyzed asymmetric addition of nitroalkanes to cyclic enones.

    Science.gov (United States)

    Hanessian, Stephen; Govindan, Subramaniyan; Warrier, Jayakumar S

    2005-11-01

    The effect of chirality and steric bulk of 2,5-disubstituted piperazines as additives in the conjugate addition of 2-nitropropane to cyclohexenone, catalyzed by l-proline, was investigated. Neither chirality nor steric bulk affects the enantioselectivity of addition, which gives 86-93% ee in the presence of achiral and chiral nonracemic 2,5-disubstituted piperazines. Proline hydroxamic acid is shown for the first time to be an effective organocatalyst in the same Michael reaction. PMID:16189834

  7. Control Strategies of Asymmetric Strip Shape in Six-High Cold Rolling Mill%Control Strategies of Asymmetric Strip Shape in Six-High Cold Rolling Mill

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yun; YANG Quan; WANG Xiao-chen

    2011-01-01

    It is a complicated problem for cold-rolled strip to improve asymmetric strip shape in strip production. A roll system and strip coupled model of six-high cold rolling mill was established with finite element method to estimate the effect of intermediate roll shifting, tilting, symmetric and asymmetric bending technologies on strip profile. To reduce asymmetric defects of strip shape as much as possible, some control strategies were proposed, including tilting and asymmetric bending of intermediate roll and work roll. The combinations of these three control strategies can effectively eliminate asymmetric strip shape defects. Finally, the closed-loop control model of asymmetric flat- ness at the last stand was given, and the flatness control system with the function of asymmetric strip shape control was also designed for cold tandem mill.

  8. Condensation on Slippery Asymmetric Bumps

    CERN Document Server

    Park, Kyoo-Chul; He, Neil; Aizenberg, Joanna

    2015-01-01

    Bumps are omnipresent from human skin to the geological structures on planets, which offer distinct advantages in numerous phenomena including structural color, drag reduction, and extreme wettability. Although the topographical parameters of bumps such as radius of curvature of convex regions significantly influence various phenomena including anti-reflective structures and contact time of impacting droplets, the effect of the detailed bump topography on growth and transport of condensates have not been clearly understood. Inspired by the millimetric bumps of the Namib Desert beetle, here we report the identified role of radius of curvature and width of bumps with homogeneous surface wettability in growth rate, coalescence and transport of water droplets. Further rational design of asymmetric convex topography and synergetic combination with slippery coating simultaneously enable self-transport, leading to unseen five-fold higher growth rate and an order of magnitude faster shedding time of droplets compared...

  9. Refractive index modulation based on excitonic effects in GaInAs-InP coupled asymmetric quantum wells

    DEFF Research Database (Denmark)

    Thirstrup, Carsten

    1995-01-01

    this strong electrorefractive effect with self-photo-induced modulation in a biased-pin-diode modulator configuration, results in an optical nonlinearity with a figure of merit of 20 cm3/J at a wavelength of 1.55 μm. This value is large compared to optical nonlinearities originating from band edge resonance...

  10. Engineered Asymmetric Synthetic Vesicles

    Science.gov (United States)

    Lu, Li; Chiarot, Paul

    2013-11-01

    Synthetic vesicles are small, fluid-filled spheres that are enclosed by a bilayer of lipid molecules. They can be used as models for investigating membrane biology and as delivery vehicles for pharmaceuticals. In practice, it is difficult to simultaneously control membrane asymmetry, unilamellarity, vesicle size, vesicle-to-vesicle uniformity, and luminal content. Membrane asymmetry, where each leaflet of the bilayer is composed of different lipids, is of particular importance as it is a feature of most natural membranes. In this study, we leverage microfluidic technology to build asymmetric vesicles at high-throughput. We use the precise flow control offered by microfluidic devices to make highly uniform emulsions, with controlled internal content, that serve as templates to build the synthetic vesicles. Flow focusing, dielectrophoretic steering, and interfacial lipid self-assembly are critical procedures performed on-chip to produce the vesicles. Fluorescent and confocal microscopy are used to evaluate the vesicle characteristics.

  11. Asymmetric black dyonic holes

    Directory of Open Access Journals (Sweden)

    I. Cabrera-Munguia

    2015-04-01

    Full Text Available A 6-parametric asymptotically flat exact solution, describing a two-body system of asymmetric black dyons, is studied. The system consists of two unequal counterrotating Kerr–Newman black holes, endowed with electric and magnetic charges which are equal but opposite in sign, separated by a massless strut. The Smarr formula is generalized in order to take into account their contribution to the mass. The expressions for the horizon half-length parameters σ1 and σ2, as functions of the Komar parameters and of the coordinate distance, are displayed, and the thermodynamic properties of the two-body system are studied. Furthermore, the seven physical parameters satisfy a simple algebraic relation which can be understood as a dynamical scenario, in which the physical properties of one body are affected by the ones of the other body.

  12. Surface segregation of conformationally asymmetric polymer blends

    OpenAIRE

    Stepanow, Semjon; Fedorenko, Andrei A.

    2005-01-01

    We have generalized the Edwards' method of collective description of dense polymer systems in terms of effective potentials to polymer blends in the presence of a surface. With this method we have studied conformationally asymmetric athermic polymer blends in the presence of a hard wall to the first order in effective potentials. For polymers with the same gyration radius $R_g$ but different statistical segment lengths $l_{A}$ and $l_{B}$ the excess concentration of stiffer polymers at the su...

  13. Force on an Asymmetric Capacitor

    CERN Document Server

    Bahder, T B; Bahder, Thomas B.; Fazi, Chris

    2002-01-01

    When a high voltage (~30 kV) is applied to a capacitor whose electrodes have different physical dimensions, the capacitor experiences a net force toward the smaller electrode (Biefeld-Brown effect). We have verified this effect by building four capacitors of different shapes. The effect may have applications to vehicle propulsion and dielectric pumps. We review the history of this effect briefly through the history of patents by Thomas Townsend Brown. At present, the physical basis for the Biefeld-Brown effect is not understood. The order of magnitude of the net force on the asymmetric capacitor is estimated assuming two different mechanisms of charge conduction between its electrodes: ballistic ionic wind and ionic drift. The calculations indicate that ionic wind is at least three orders of magnitude too small to explain the magnitude of the observed force on the capacitor. The ionic drift transport assumption leads to the correct order of magnitude for the force, however, it is difficult to see how ionic dr...

  14. Loss Aversion and the Asymmetric Transmission of Monetary Policy

    DEFF Research Database (Denmark)

    Santoro, Emiliano; Petrella, Ivan; Pfajfar, Damjan;

    2014-01-01

    There is widespread evidence that monetary policy exerts asymmetric effects on output over contractions and expansions in economic activity, while price responses display no sizeable asymmetry. To rationalize these facts we develop a dynamic general equilibrium model where households’ utility...

  15. The Inhibitory Effect of Quercetin on Asymmetric Dimethylarginine-Induced Apoptosis Is Mediated by the Endoplasmic Reticulum Stress Pathway in Glomerular Endothelial Cells

    Directory of Open Access Journals (Sweden)

    Weikang Guo

    2014-01-01

    Full Text Available Asymmetric dimethylarginine (ADMA is considered an independent mortality and cardiovascular risk factor in chronic kidney disease (CKD patients, and contributes to the development of renal fibrosis. Quercetin (QC, a natural component of foods, protects against renal injury. Here, we explored the possible mechanisms that are responsible for ADMA-induced renal fibrosis and the protective effect of QC. We found that ADMA treatment activated the endoplasmic reticulum (ER stress sensor proteins phosphorylated protein kinase RNA-activated-like ER kinase (PERK and inositol requiring-1α (IRE1, which correspondingly induced C/EBP homologous protein (CHOP expression and phosphorylated c-Jun N-terminal kinase (JNK phosphorylation in glomerular endothelial cells (GEnCs. Following this, ADMA promoted ER stress-induced apoptosis and resulted in transforming growth factor β (TGF-β expression in GEnCs. SP600125, an inhibitor of JNK, and CHOP siRNA protected against ADMA-induced cell apoptosis and TGF-β expression. QC prevented ADMA-induced PERK and IRE1 apoptotic ER stress pathway activation. Also, ADMA-induced GEnCs apoptosis and TGF-β expression was reduced by QC. Overexpression of CHOP blocked QC-mediated protection from apoptosis in ER stressed cells. Overall, these observations indicate that ADMA may induce GEnCs apoptosis and TGF-β expression by targeting the PERK-CHOP and IRE1-JNK pathway. In addition, drugs such as QC targeting ER stress may hold great promise for the development of novel therapies against ADMA-induced renal fibrosis.

  16. Error induced by the estimation of the corneal power and the effective lens position with a rotationally asymmetric refractive multifocal intraocular lens

    Institute of Scientific and Technical Information of China (English)

    David; P.Piero; Vicente; J.Camps; María; L.Ramón; Verónica; Mateo; Rafael; J.Pérez-Cambrodí

    2015-01-01

    AIM : To evaluate the prediction error in intraocular lens(IOL) power calculation for a rotationally asymmetric refractive multifocal IOL and the impact on this error of the optimization of the keratometric estimation of the corneal power and the prediction of the effective lens position(ELP).METHODS: Retrospective study including a total of 25 eyes of 13 patients(age, 50 to 83y) with previous cataract surgery with implantation of the Lentis Mplus LS-312 IOL(Oculentis Gmb H, Germany). In all cases, an adjusted IOL power(P IOLadj) was calculated based on Gaussian optics using a variable keratometric index value(n kadj) for the estimation of the corneal power(P kadj) and on a new value for ELP(ELP adj) obtained by multiple regression analysis.This P IOLadj was compared with the IOL power implanted(P IOLReal) and the value proposed by three conventional formulas(Haigis, Hoffer Q and Holladay Ⅰ).RESULTS: P IOLReal was not significantly different than P IOLadj and Holladay IOL power(P >0.05). In the Bland and Altman analysis, P IOLadj showed lower mean difference(-0.07 D) and limits of agreement(of 1.47 and-1.61 D)when compared to P IOLReal than the IOL power value obtained with the Holladay formula. Furthermore, ELP adj was significantly lower than ELP calculated with other conventional formulas(P <0.01) and was found to be dependent on axial length, anterior chamber depth and P kadj. CONCLUSION: Refractive outcomes after cataract surgery with implantation of the multifocal IOL Lentis Mplus LS-312 can be optimized by minimizing thekeratometric error and by estimating ELP using a mathematical expression dependent on anatomical factors.

  17. Rawal's catalyst as an effective stimulant for the highly asymmetric Michael addition of β-keto esters to functionally rich nitro-olefins.

    Science.gov (United States)

    Suresh Kumar, A; Prabhakar Reddy, T; Madhavachary, R; Ramachary, Dhevalapally B

    2016-06-15

    A general approach to asymmetric synthesis of highly substituted dihydroquinolines was achieved through neighboring ortho-amino group engaged sequential Michael/amination/dehydration reactions on (E)-2-(2-nitrovinyl)anilines with cyclic and acyclic β-keto esters in the presence of a catalytic amount of Rawal's quinidine-NH-benzyl squaramide followed by TFA. PMID:26611712

  18. Asymmetric Gepner Models (Revisited)

    CERN Document Server

    Gato-Rivera, B

    2010-01-01

    We reconsider a class of heterotic string theories studied in 1989, based on tensor products of N=2 minimal models with asymmetric simple current invariants. We extend this analysis from (2,2) and (1,2) spectra to (0,2) spectra with SO(10) broken to the Standard Model. In the latter case the spectrum must contain fractionally charged particles. We find that in nearly all cases at least some of them are massless. However, we identify a large subclass where the fractional charges are at worst half-integer, and often vector-like. The number of families is very often reduced in comparison to the 1989 results, but there are no new tensor combinations yielding three families. All tensor combinations turn out to fall into two classes: those where the number of families is always divisible by three, and those where it is never divisible by three. We find an empirical rule to determine the class, which appears to extend beyond minimal N=2 tensor products. We observe that distributions of physical quantities such as th...

  19. Magnetically Modified Asymmetric Supercapacitors Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This Small Business Innovation Research Phase I project is for the development of an asymmetric supercapacitor that will have improved energy density and cycle...

  20. Do Daily Retail Gasoline Prices adjust Asymmetrically?

    OpenAIRE

    Bettendorf, Leon; Geest, Stéphanie; Kuper, G.

    2005-01-01

    This paper analyzes adjustments in the Dutch retail gasoline prices. We estimate an error correction model on changes in the daily retail price for gasoline (taxes excluded) for the period 1996-2004 taking care of volatility clustering by estimating an EGARCH model. It turns out the volatility process is asymmetrical: an unexpected increase in the producer price has a larger effect on the variance of the producer price than an unexpected decrease. We do not find evidence for amount asymmetry,...

  1. Multicatalyst system in asymmetric catalysis

    CERN Document Server

    Zhou, Jian

    2014-01-01

    This book introduces multi-catalyst systems by describing their mechanism and advantages in asymmetric catalysis.  Helps organic chemists perform more efficient catalysis with step-by-step methods  Overviews new concepts and progress for greener and economic catalytic reactions  Covers topics of interest in asymmetric catalysis including bifunctional catalysis, cooperative catalysis, multimetallic catalysis, and novel tandem reactions   Has applications for pharmaceuticals, agrochemicals, materials, and flavour and fragrance

  2. On Asymmetric Quantum MDS Codes

    CERN Document Server

    Ezerman, Martianus Frederic; Ling, San

    2010-01-01

    Assuming the validity of the MDS Conjecture, the weight distribution of all MDS codes is known. Using a recently-established characterization of asymmetric quantum error-correcting codes, linear MDS codes can be used to construct asymmetric quantum MDS codes with $d_{z} \\geq d_{x}\\geq 2$ for all possible values of length $n$ for which linear MDS codes over $\\F_{q}$ are known to exist.

  3. Mobile Termination with Asymmetric Networks

    OpenAIRE

    Dewenter, Ralf; Haucap, Justus

    2003-01-01

    This paper examines mobile termination fees and their regulation when networks are asymmetric in size. It is demonstrated that with consumer ignorance about the exact termination rates (a) a mobile network?s termination rate is the higher the smaller the network?s size (as measured through its subscriber base) and (b) asymmetric regulation of only the larger operators in a market will, ce-teris paribus, induce the smaller operators to increase their termination rates. The results are supporte...

  4. Asymmetric Conditional Volatility in International Stock Markets

    CERN Document Server

    Ferreira, N B; Menezes, R; Ferreira, Nuno B.; Mendes, Diana A.; Menezes, Rui

    2006-01-01

    Recent studies show that a negative shock in stock prices will generate more volatility than a positive shock of similar magnitude. The aim of this paper is to appraise the hypothesis under which the conditional mean and the conditional variance of stock returns are asymmetric functions of past information. We compare the results for the Portuguese Stock Market Index PSI 20 with six other Stock Market Indices, namely the S&P 500, FTSE100, DAX 30, CAC 40, ASE 20, and IBEX 35. In order to assess asymmetric volatility we use autoregressive conditional heteroskedasticity specifications known as TARCH and EGARCH. We also test for asymmetry after controlling for the effect of macroeconomic factors on stock market returns using TAR and M-TAR specifications within a VAR framework. Our results show that the conditional variance is an asymmetric function of past innovations raising proportionately more during market declines, a phenomenon known as the leverage effect. However, when we control for the effect of chan...

  5. Asymmetric Gepner models (revisited)

    Energy Technology Data Exchange (ETDEWEB)

    Gato-Rivera, B. [NIKHEF Theory Group, Kruislaan 409, 1098 SJ Amsterdam (Netherlands)] [Instituto de Fisica Fundamental, CSIC, Serrano 123, Madrid 28006 (Spain); Schellekens, A.N., E-mail: t58@nikhef.n [NIKHEF Theory Group, Kruislaan 409, 1098 SJ Amsterdam (Netherlands)] [Instituto de Fisica Fundamental, CSIC, Serrano 123, Madrid 28006 (Spain)] [IMAPP, Radboud Universiteit, Nijmegen (Netherlands)

    2010-12-11

    We reconsider a class of heterotic string theories studied in 1989, based on tensor products of N=2 minimal models with asymmetric simple current invariants. We extend this analysis from (2,2) and (1,2) spectra to (0,2) spectra with SO(10) broken to the Standard Model. In the latter case the spectrum must contain fractionally charged particles. We find that in nearly all cases at least some of them are massless. However, we identify a large subclass where the fractional charges are at worst half-integer, and often vector-like. The number of families is very often reduced in comparison to the 1989 results, but there are no new tensor combinations yielding three families. All tensor combinations turn out to fall into two classes: those where the number of families is always divisible by three, and those where it is never divisible by three. We find an empirical rule to determine the class, which appears to extend beyond minimal N=2 tensor products. We observe that distributions of physical quantities such as the number of families, singlets and mirrors have an interesting tendency towards smaller values as the gauge groups approaches the Standard Model. We compare our results with an analogous class of free fermionic models. This displays similar features, but with less resolution. Finally we present a complete scan of the three family models based on the triply-exceptional combination (1,16{sup *},16{sup *},16{sup *}) identified originally by Gepner. We find 1220 distinct three family spectra in this case, forming 610 mirror pairs. About half of them have the gauge group SU(3)xSU(2){sub L}xSU(2){sub R}xU(1){sup 5}, the theoretical minimum, and many others are trinification models.

  6. Effects of dope extrusion rate on the morphology and gas separation performance of asymmetric polysulfone hollow fiber membranes for O2/N2 separation

    Directory of Open Access Journals (Sweden)

    Ahmad Fausi Ismail

    2002-11-01

    Full Text Available The objective of this study was to investigate the influence of dope extrusion rates on morphology and gas separation performance of asymmetric polysulfone hollow fiber membranes. Asymmetric polysulfone hollow fiber membranes for gas separation were prepared from a solution consisting of 26.0 wt. % of polysulfone, 30.4 wt. % of N, N-dimethylacetamide, 30.4 wt. % of tetrahydrofuran and 13.2 wt. % ethanol. The dry/wet phase separation process was applied to a dry/wet spinning process. Fibers were spun at various dope extrusion rates (DER ranging from 1.5 - 3.0 cm3/min and hence at different levels of shear. The results suggest that as the dope extrusion rate is increased, the selectivity will increase until a critical level of shear is reached, beyond which the membrane performance deteriorates. Pressure-normalized-fluxes and selectivities were evaluated by using pure oxygen and nitrogen as test gases.

  7. L-Valine derived chiral N-sulfinamides as effective organocatalysts for the asymmetric hydrosilylation of N-alkyl and N-aryl protected ketimines.

    Science.gov (United States)

    Wang, Chao; Wu, Xinjun; Zhou, Li; Sun, Jian

    2015-01-14

    L-Valine derived N-sulfinamides have been developed as efficient enantioselective Lewis basic organocatalysts for the asymmetric reduction of N-aryl and N-alkyl ketimines with trichlorosilane. Catalyst 3c afforded up to 99% yield and 96% ee in the reduction of N-alkyl ketimines and up to 98% yield and 98% ee in the reduction of N-aryl ketimines.

  8. Effect of carboxyl anchoring groups in asymmetric zinc phthalocyanine with large steric hindrance on the dye-sensitized solar cell performance

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Wenye; Peng, Bosi; Lin, Li; Li, Renjie; Zhang, Jing, E-mail: jzhang03@whu.edu.cn; Peng, Tianyou, E-mail: typeng@whu.edu.cn

    2015-08-01

    Asymmetric zinc phthalocyanines containing tribenzonaphtho-condensed porphyrazine with six bulky diphenylphenoxy and one or two carboxyl groups are used as sensitizers for dye-sensitized solar cells (DSSCs). It is found that Zn-tri-PcNc-4 having two carboxyl groups shows a slight redshift in the Q-band absorption but a significantly decreased absorbance as compared with Zn-tri-PcNc-8 having one carboxyl group, and Zn-tri-PcNc-4 can be more stably and perpendicularly grafted onto the TiO{sub 2} surface than Zn-tri-PcNc-8, which further leads to the differences in the interfacial charge transfer dynamics and dye-loaded amount. Zn-tri-PcNc-4 with two carboxyl groups grafted onto the TiO{sub 2} electrode surface of DSSC results in a photovoltaic conversion efficiency of 3.22%, higher than that (3.01%) of the analog with one carboxyl group (Zn-tri-PcNc-8), which exhibits a lower short-circuit current but much higher open-circuit voltage. The additional carboxyl group in Zn-tri-PcNc-4 leads to the enhanced dye-loaded amount and the molecular orbital energy level shift toward positive direction, causing more efficient electron injection and higher short-circuit current than Zn-tri-PcNc-8; while the two carboxyl groups of Zn-tri-PcNc-4 would cause more protonation of TiO{sub 2} surface, which possibly leads to the downward shift of TiO{sub 2} conduction band edge, and then to the decreased open-circuit voltage. The present results demonstrate the molecular engineering aspect of ZnPc dyes in which the fine tuning of the energy levels and molecular structures is crucial for high conversion efficiency of DSSCs. - Highlights: • ZnPcs with six diphenylphenoxy and one/two carboxyl groups are used as dyes for DSSCs. • Effect of carboxyl group number on the ZnPc-sensitized cell property are scrutinized. • Grafting two carboxyl groups on ZnPc leads to the enhanced photocurrent and efficiency. • ZnPc with one COOH has a higher open-circuit voltage than its analog with two

  9. Effects of regenerative radioelectric asymmetric conveyer treatment on human normal and osteoarthritic chondrocytes exposed to IL-1β. A biochemical and morphological study

    Directory of Open Access Journals (Sweden)

    Collodel G

    2013-03-01

    Full Text Available Giulia Collodel,1 Antonella Fioravanti,2 Nicola Antonio Pascarelli,2 Antonello Lamboglia,2 Vania Fontani,3 Margherita Maioli,3–5 Sara Santaniello,4,5 Gianfranco Pigliaru,4,5 Alessandro Castagna,3 Elena Moretti,1 Francesca Iacoponi,1 Salvatore Rinaldi,3 Carlo Ventura3,5,6 1Department of Biomedical Sciences (Applied Biology, 2Department of Clinical Medicine and Immunological Sciences (Rheumatology Unit, University of Siena, Siena, Italy; 3Department of Regenerative Medicine, Rinaldi Fontani Institute, Florence, Italy; 4Department of Biomedical Sciences, University of Sassari, Sassari, Italy; 5Laboratory of Molecular Biology and Stem Cell Engineering, National Institute of Biostructures and Biosystems, Bologna, Italy; 6Cardiovascular Department, S Orsola-Malpighi Hospital, University of Bologna, Bologna, Italy Purpose: Osteoarthritis (OA is a degenerative disease characterized by a progressive loss of articular cartilage extracellular matrix and is due to functional impairments occurring in chondrocytes. In previous works, we highlighted that Regenerative Tissue Optimization (TO-RGN treatment with radioelectric asymmetric conveyer (REAC technology influenced the gene expression profiles controlling stem cell differentiation and the pluripotency of human skin-derived fibroblasts in vitro. Since interleukin-1 beta signaling has been implicated in the induction and progression of this disease (through metalloproteinase-3 synthesis and nitric oxide production, we investigated whether REAC TO-RGN might influence the biochemical and morphological changes induced by interleukin-1 beta in normal and OA chondrocytes. Methods: The induction of metalloproteinase-3 and proteoglycan synthesis was evaluated by a solid-phase enzyme-amplified sensitivity immunoassay, and nitric oxide production was evaluated with the Griess method. Ultrastructural features were observed by transmission electron microscopy. Results: REAC TO-RGN treatment decreased nitric oxide

  10. Cosmological signatures of time-asymmetric gravity

    CERN Document Server

    Cortês, Marina; Smolin, Lee

    2016-01-01

    We develop the model proposed by Cort\\^es, Gomes & Smolin, to predict cosmological signatures of time-asymmetric extensions of general relativity they proposed recently. Within this class of models the equation of motion of chiral fermions is modified by a torsion term. This term leads to a dispersion law for neutrinos that associates a new time-varying energy with each particle. We find a new neutrino contribution to the Friedmann equation resulting from the torsion term in the Ashtekar connection. In this note we explore the phenomenology of this term and observational consequences for cosmological evolution. We show that constraints on the critical energy density will ordinarily render this term unobservably small, a maximum of order $10^{-25}$ of the neutrino energy density today. However, if the time-asymmetric dark energy is tuned to cancel the cosmological constant, the torsion effect may be a dark matter candidate.

  11. 带材非对角非对称巨磁阻抗效应传感机理建模%Sensing mechanism modeling of off-diagonal asymmetric giant magnetoimpedance effect in ribbons

    Institute of Scientific and Technical Information of China (English)

    柴秀丽; 甘志华; 闫萍

    2011-01-01

    Mechanism modeling of off-diagonal asymmetric giant magnetoimpedance effect is vital for the development of high sensitive giant magnetoimpedance magnetic sensor. Three operation patterns of asymmetric giant magnetoimpedance effect are considered and the theoretical model of ribbon high-frequency characteristics is established. The expression of off-diagonal voltage is derived based on linear Landau-Iifshitz kinetic equation and Maxwell equations, and the effects of amorphous thickness and DC bias current amplitude on off-diagonal voltage of external fields are numerically analyzed and discussed. Simulation results agree with the experimental ones. The proposed model is effective and correct, which provides an extensive guidance for more systematic and comprehensive study of asymmetric giant magnetoimpedance effect. The results will contribute to the development of high-performance magnetic sensor.%非对角非对称巨磁阻抗效应机理建模是研制高灵敏巨磁阻抗磁传感器的重要基础工作.综合考虑非对称巨磁阻抗效应存在的3种工作模式,建立带材高频特性的理论模型,基于线性Landau-Lifshitz动力学方程和Maxwell方程推导传感用非对角电压的表达式,数值分析讨论非晶层厚度和直流偏置电流对输出电压场特性的影响.研究结果与实验结果相符合,表明所建立模型方法是有效的、正确的,对更加系统、全面研究非对称巨磁阻抗效应具有一定的指导价值,有助于高性能的磁传感器的研制.

  12. Modeling of asymmetrical boost converters

    Directory of Open Access Journals (Sweden)

    Eliana Isabel Arango Zuluaga

    2014-03-01

    Full Text Available The asymmetrical interleaved dual boost (AIDB is a fifth-order DC/DC converter designed to interface photovoltaic (PV panels. The AIDB produces small current harmonics to the PV panels, reducing the power losses caused by the converter operation. Moreover, the AIDB provides a large voltage conversion ratio, which is required to step-up the PV voltage to the large dc-link voltage used in grid-connected inverters. To reject irradiance and load disturbances, the AIDB must be operated in a closed-loop and a dynamic model is required. Given that the AIDB converter operates in Discontinuous Conduction Mode (DCM, classical modeling approaches based on Continuous Conduction Mode (CCM are not valid. Moreover, classical DCM modeling techniques are not suitable for the AIDB converter. Therefore, this paper develops a novel mathematical model for the AIDB converter, which is suitable for control-pur-poses. The proposed model is based on the calculation of a diode current that is typically disregarded. Moreover, because the traditional correction to the second duty cycle reported in literature is not effective, a new equation is designed. The model accuracy is contrasted with circuital simulations in time and frequency domains, obtaining satisfactory results. Finally, the usefulness of the model in control applications is illustrated with an application example.

  13. Asymmetric dynamic phase holographic grating in nematic liquid crystal

    Science.gov (United States)

    Ren, Chang-Yu; Shi, Hong-Xin; Ai, Yan-Bao; Yin, Xiang-Bao; Wang, Feng; Ding, Hong-Wei

    2016-09-01

    A new scheme for recording a dynamic phase grating with an asymmetric profile in C60-doped homeotropically aligned nematic liquid crystal (NLC) was presented. An oblique incidence beam was used to record the thin asymmetric dynamic phase holographic grating. The diffraction efficiency we achieved is more than 40%, exceeding the theoretical limit for symmetric profile gratings. Both facts can be explained by assuming that a grating with an asymmetric saw-tooth profile is formed in the NLC. Finally, physical mechanism and mathematical model for characterizing the asymmetric phase holographic grating were presented, based on the photo-refractive-like (PR-like) effect. Project supported by the Science and Technology Programs of the Educational Committee of Heilongjiang Province, China (Grant No. 12541730) and the National Natural Science Foundation of China (Grant No. 61405057).

  14. Asymmetric wave transmission in a diatomic acoustic/elastic metamaterial

    Science.gov (United States)

    Li, Bing; Tan, K. T.

    2016-08-01

    Asymmetric acoustic/elastic wave transmission has recently been realized using nonlinearity, wave diffraction, or bias effects, but always at the cost of frequency distortion, direction shift, large volumes, or external energy. Based on the self-coupling of dual resonators, we propose a linear diatomic metamaterial, consisting of several small-sized unit cells, to realize large asymmetric wave transmission in low frequency domain (below 1 kHz). The asymmetric transmission mechanism is theoretically investigated, and numerically verified by both mass-spring and continuum models. This passive system does not require any frequency conversion or external energy, and the asymmetric transmission band can be theoretically predicted and mathematically controlled, which extends the design concept of unidirectional transmission devices.

  15. Asymmetric nuclear matter equation of state

    Energy Technology Data Exchange (ETDEWEB)

    Bombaci, I.; Lombardo, U. (Dipartimento di Fisica, Universita di Catania, Corso Italia 57, Catania (Italy) Istituto Nazionale di Fisica Nucleare, Sezione di Catania, Corso Italia 57, I-95129 Catania (Italy))

    1991-11-01

    Systematic calculations of asymmetric nuclear matter have been performed in the framework of the Brueckner-Bethe-Goldstone approach in a wide range of both density and asymmetry parameter. The empirical parabolic law fulfilled by the binding energy per nucleon is confirmed by the present results in all the range of the asymmetry parameter values. The predominant role of the {sup 3}{ital S}{sub 1-}{sup 3}{ital D}{sub 1} component of the {ital NN} interaction is elucidated. A linear variation of the proton and neutron single-particle potentials is found as increasing the neutron excess; a deviation from the phenomenological potentials occurs for highly asymmetric matter as an effect of the self-consistency. The present calculations of the incompressibility predict a strong softening of the equation of state going from symmetric to asymmetric nuclear matter. The proton fraction in equilibrium with neutron matter has been determined from the beta-stability condition and its relevance to the superfluidity of neutron stars has been investigated.

  16. Traceless Synthesis of Asymmetrically Modified Bivalent Nucleosomes.

    Science.gov (United States)

    Lechner, Carolin C; Agashe, Ninad D; Fierz, Beat

    2016-02-18

    Nucleosomes carry extensive post-translational modifications (PTMs), which results in complex modification patterns that are involved in epigenetic signaling. Although two copies of each histone coexist in a nucleosome, they may not carry the same PTMs and are often differently modified (asymmetric). In bivalent domains, a chromatin signature prevalent in embryonic stem cells (ESCs), namely H3 methylated at lysine 4 (H3K4me3), coexists with H3K27me3 in asymmetric nucleosomes. We report a general, modular, and traceless method for producing asymmetrically modified nucleosomes. We further show that in bivalent nucleosomes, H3K4me3 inhibits the activity of the H3K27-specific lysine methyltransferase (KMT) polycomb repressive complex 2 (PRC2) solely on the same histone tail, whereas H3K27me3 stimulates PRC2 activity across tails, thereby partially overriding the H3K4me3-mediated repressive effect. To maintain bivalent domains in ESCs, PRC2 activity must thus be locally restricted or reversed.

  17. Asymmetric distances for binary embeddings.

    Science.gov (United States)

    Gordo, Albert; Perronnin, Florent; Gong, Yunchao; Lazebnik, Svetlana

    2014-01-01

    In large-scale query-by-example retrieval, embedding image signatures in a binary space offers two benefits: data compression and search efficiency. While most embedding algorithms binarize both query and database signatures, it has been noted that this is not strictly a requirement. Indeed, asymmetric schemes that binarize the database signatures but not the query still enjoy the same two benefits but may provide superior accuracy. In this work, we propose two general asymmetric distances that are applicable to a wide variety of embedding techniques including locality sensitive hashing (LSH), locality sensitive binary codes (LSBC), spectral hashing (SH), PCA embedding (PCAE), PCAE with random rotations (PCAE-RR), and PCAE with iterative quantization (PCAE-ITQ). We experiment on four public benchmarks containing up to 1M images and show that the proposed asymmetric distances consistently lead to large improvements over the symmetric Hamming distance for all binary embedding techniques.

  18. Nuclear matter effects on $J/\\psi$ production in asymmetric Cu+Au collisions at $\\sqrt{s_{_{NN}}}$ = 200 GeV

    OpenAIRE

    Aidala, C.; Ajitanand, N. N.; Akiba, Y; Akimoto, R.; Alexander, J.; Aoki, K.; Apadula, N.; Asano, H.; Atomssa, E. T.; Awes, T. C.; Azmoun, B.; Babintsev, V.; Bai, M.; Bai, X.; Bannier, B.

    2014-01-01

    We report on $J/\\psi$ production from asymmetric Cu+Au heavy-ion collisions at $\\sqrt{s_{_{NN}}}$=200 GeV at the Relativistic Heavy Ion Collider at both forward (Cu-going direction) and backward (Au-going direction) rapidities. The nuclear modification of $J/\\psi$ yields in Cu$+$Au collisions in the Au-going direction is found to be comparable to that in Au$+$Au collisions when plotted as a function of the number of participating nucleons. In the Cu-going direction, $J/\\psi$ production shows ...

  19. CMISTARK: Python package for the Stark-effect calculation and symmetry classification of linear, symmetric and asymmetric top wavefunctions in dc electric fields

    CERN Document Server

    Chang, Yuan-Pin; Sartakov, Boris; Küpper, Jochen

    2013-01-01

    The Controlled Molecule Imaging group (CMI) at the Center for Free Electron Laser Science (CFEL) has developed the CMIstark software to calculate, view, and analyze the energy levels of adiabatic Stark energy curves of linear, symmetric top and asymmetric top molecules. The program exploits the symmetry of the Hamiltonian to generate fully labeled adiabatic Stark energy curves. CMIstark is written in Python and easily extendable, while the core numer- ical calculations make use of machine optimized BLAS and LAPACK routines. Calculated energies are stored in HDF5 files for convenient access and programs to extract ASCII data or to generate graphical plots are provided.

  20. Asymmetric Synthesis via Chiral Aziridines

    DEFF Research Database (Denmark)

    Tanner, David Ackland; Harden, Adrian; Wyatt, Paul;

    1996-01-01

    A series of chiral bis(aziridines) has been synthesised and evaluated as chelating ligands for a variety of asymmetric transformations mediated by metals [Os (dihydroxylation), Pd (allylic alkylation) Cu (cyclopropanation and aziridination, Li (1,2-addition of organolithiums to imines)]. In the b......A series of chiral bis(aziridines) has been synthesised and evaluated as chelating ligands for a variety of asymmetric transformations mediated by metals [Os (dihydroxylation), Pd (allylic alkylation) Cu (cyclopropanation and aziridination, Li (1,2-addition of organolithiums to imines...

  1. Ideal 3D asymmetric concentrator

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Botella, Angel [Departamento Fisica Aplicada a los Recursos Naturales, Universidad Politecnica de Madrid, E.T.S.I. de Montes, Ciudad Universitaria s/n, 28040 Madrid (Spain); Fernandez-Balbuena, Antonio Alvarez; Vazquez, Daniel; Bernabeu, Eusebio [Departamento de Optica, Universidad Complutense de Madrid, Fac. CC. Fisicas, Ciudad Universitaria s/n, 28040 Madrid (Spain)

    2009-01-15

    Nonimaging optics is a field devoted to the design of optical components for applications such as solar concentration or illumination. In this field, many different techniques have been used for producing reflective and refractive optical devices, including reverse engineering techniques. In this paper we apply photometric field theory and elliptic ray bundles method to study 3D asymmetric - without rotational or translational symmetry - concentrators, which can be useful components for nontracking solar applications. We study the one-sheet hyperbolic concentrator and we demonstrate its behaviour as ideal 3D asymmetric concentrator. (author)

  2. Incompressibility of asymmetric nuclear matter

    OpenAIRE

    Chen, Lie-Wen; Cai, Bao-Jun; Shen, Chun; Ko, Che Ming; Xu, Jun; Li, Bao-An(Department of Physics and Astronomy, Texas A&M University-Commerce, Commerce, TX, 75429-3011, USA)

    2009-01-01

    The incompressibility $K_sat(\\delta)$ of isospin asymmetric nuclear matter at its saturation density. Our results show that in the expansion of $K_sat(\\delta)$ in powers of isospin asymmetry $\\delta$, i.e., $K_sat(\\delta )$=K_{0}+K_{sat,2}\\delta^{2}+K_{sat,4}\\delta^{4}+O(\\delta^{6})$, the magnitude of the 4th-order K_{sat,4} parameter is generally small. The 2nd-order K_{sat,2} parameter thus essentially characterizes the isospin dependence of the incompressibility of asymmetric nuclear matte...

  3. Forces between asymmetric polymer brushes

    OpenAIRE

    Shim, D.F.K.; Cates, M. E.

    1990-01-01

    We study the equilibrium compression of asymmetric polymer brushes grafted on flat plates, under athermal and theta solvent conditions, using a lattice self-consistent field (SCF) approach. We find that the separation d between two plates coated asymmetrically with brushes of type 1 and 2, as a function of the force F, obeys the "bisection rule", d(F) = (d1(F) + d 2(F)) /2 where d1(F)and d 2(F) are the corresponding separations for the symmetric brushes of type 1 and 2 respectively.The bisect...

  4. Research on asymmetric "Jerusalem" unit

    Institute of Scientific and Technical Information of China (English)

    Jun Lu; Jianbo Wang

    2009-01-01

    An asymmetric Jerusalem unit and the frequency selective surface(FSS)structure composed of such units are designed.The transmittance of the designed FSS structure is calculated by mode-matching method and compared with the test results.The comparison results show that the FSS center frequency of the asymmetric structure unit drifts little with the variation of the incident angles of the electromagnetic waves and keeps relatively stable.The research offers a new choice for the application of FSS under the large scanning angle of electromagnetic waves.

  5. Asymmetric central bank preferences and inflation rate in Tunisia

    Directory of Open Access Journals (Sweden)

    Imen KOBBI

    2013-04-01

    Full Text Available This article fits into the new strand of literature related to the asymmetric central bank preferences and its effect on the inflation dynamic. In reality, the central banker preferences are more likely to be asymmetric. Central banker can be, for various reasons, more averse toward deviations from target with one sign more than deviations from target with the other sign. The interaction of asymmetric central bank preferences with uncertainty arising from the volatility of inflation and output may affect the inflation movements. This paper aims to check the hypothesis that asymmetric central bank preferences are able to explain inflation rate for the case of Tunisia and to understand Central Bank of Tunisia preferences toward inflation rate and output during the period ranging from 1993 to 2010. We refer to a standard monetary model that includes asymmetric loss function and a linear supply curve which acts as a constraint on the central bank behavior. The results show that the inflation rate depends on the output gap and on the conditional variance of inflation and provide evidence for asymmetric central bank preferences. The Central Bank of Tunisia seems to be more averse to high inflation which is consistent with its ultimate goal explicitly announced to preserve price stability.

  6. Synthesis of Asymmetric Propanetriol Analogues

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    From natural tartaric acid, (R)-2-benzyloxy-3-(2-tetrahydropyranyloxy) propanol 3 was designed and synthesized, and (R)-2-benzyloxy-3-(4-methoxybenzyloxy) propanol 7 was prepared in a new method. They can be used as chiral synthons of lysophosphatidic acid and other compounds with asymmetric propanetriol backbone.

  7. Vertical asymmetric double quantum dots

    Science.gov (United States)

    Roßbach, R.; Reischle, M.; Beirne, G. J.; Schweizer, H.; Jetter, M.; Michler, P.

    2007-01-01

    Two layers of differently sized self-assembled InP-quantum dots (QDs) separated by a GaInP spacer layer with varying thickness were grown by metal organic vapor phase epitaxy (MOVPE). Photoluminescence measurements of the QD ensembles and of individual asymmetric double QDS show coupling due to the tunnelling of carriers.

  8. Asymmetrical Switch Costs in Children

    Science.gov (United States)

    Ellefson, Michelle R.; Shapiron, Laura R.; Chater, Nick

    2006-01-01

    Switching between tasks produces decreases in performance as compared to repeating the same task. Asymmetrical switch costs occur when switching between two tasks of unequal difficulty. This asymmetry occurs because the cost is greater when switching to the less difficult task than when switching to the more difficult task. Various theories about…

  9. Investigation of Asymmetric Thrust Detection with Demonstration in a Real-Time Simulation Testbed

    Science.gov (United States)

    Chicatelli, Amy K.; Rinehart, Aidan W.; Sowers, T. Shane; Simon, Donald L.

    2016-01-01

    The purpose of this effort is to develop, demonstrate, and evaluate three asymmetric thrust detection approaches to aid in the reduction of asymmetric thrust-induced aviation accidents. This paper presents the results from that effort and their evaluation in simulation studies, including those from a real-time flight simulation testbed. Asymmetric thrust is recognized as a contributing factor in several Propulsion System Malfunction plus Inappropriate Crew Response (PSM+ICR) aviation accidents. As an improvement over the state-of-the-art, providing annunciation of asymmetric thrust to alert the crew may hold safety benefits. For this, the reliable detection and confirmation of asymmetric thrust conditions is required. For this work, three asymmetric thrust detection methods are presented along with their results obtained through simulation studies. Representative asymmetric thrust conditions are modeled in simulation based on failure scenarios similar to those reported in aviation incident and accident descriptions. These simulated asymmetric thrust scenarios, combined with actual aircraft operational flight data, are then used to conduct a sensitivity study regarding the detection capabilities of the three methods. Additional evaluation results are presented based on pilot-in-the-loop simulation studies conducted in the NASA Glenn Research Center (GRC) flight simulation testbed. Data obtained from this flight simulation facility are used to further evaluate the effectiveness and accuracy of the asymmetric thrust detection approaches. Generally, the asymmetric thrust conditions are correctly detected and confirmed.

  10. Asymmetric Carrier Random PWM

    DEFF Research Database (Denmark)

    Mathe, Laszlo; Lungeanu, Florin; Rasmussen, Peter Omand;

    2010-01-01

    This paper presents a new fixed carrier frequency random PWM method, where a new type of carrier wave is proposed for modulation. Based on the measurements, it is shown that the spread effect of the discrete components from the motor current spectra is very effective independent of the modulation...

  11. Asymmetric Heat Conduction in One-Dimensional Hard-Point Model with Mass Gradient

    Institute of Scientific and Technical Information of China (English)

    LI Hai-Bin; NIE Qing-Miao; XIN Xiao-Tian

    2009-01-01

    The heat conduction in a one-dimensional (1D) hard-point model with mass gradient is studied. Using numerical simulation, we find an asymmetric heat conduction in this model with greater heat current in the direction of mass increase. The increase of temperature gradient, mass gradient and system size are found to enhance the asymmetric heat conduction. Based on the collision dynamic of a hard-point particle, we give a qualitative explanation for the underlying mechanism of asymmetric effect.

  12. Selfhealing of asymmetric Bessel-like modes

    DEFF Research Database (Denmark)

    Israelsen, Stine Møller; Rishøj, Lars Søgaard; Rottwitt, Karsten

    2014-01-01

    We numerically investigate asymmetric Bessel-like modes in an aircladding fiber. The selfhealing ability of asymmetric Bessel-like modes is demonstrated and quantified including the angular dependency of this ability.......We numerically investigate asymmetric Bessel-like modes in an aircladding fiber. The selfhealing ability of asymmetric Bessel-like modes is demonstrated and quantified including the angular dependency of this ability....

  13. Iron-, Cobalt-, and Nickel-Catalyzed Asymmetric Transfer Hydrogenation and Asymmetric Hydrogenation of Ketones.

    Science.gov (United States)

    Li, Yan-Yun; Yu, Shen-Luan; Shen, Wei-Yi; Gao, Jing-Xing

    2015-09-15

    Chiral alcohols are important building blocks in the pharmaceutical and fine chemical industries. The enantioselective reduction of prochiral ketones catalyzed by transition metal complexes, especially asymmetric transfer hydrogenation (ATH) and asymmetric hydrogenation (AH), is one of the most efficient and practical methods for producing chiral alcohols. In both academic laboratories and industrial operations, catalysts based on noble metals such as ruthenium, rhodium, and iridium dominated the asymmetric reduction of ketones. However, the limited availability, high price, and toxicity of these critical metals demand their replacement with abundant, nonprecious, and biocommon metals. In this respect, the reactions catalyzed by first-row transition metals, which are more abundant and benign, have attracted more and more attention. As one of the most abundant metals on earth, iron is inexpensive, environmentally benign, and of low toxicity, and as such it is a fascinating alternative to the precious metals for catalysis and sustainable chemical manufacturing. However, iron catalysts have been undeveloped compared to other transition metals. Compared with the examples of iron-catalyzed asymmetric reduction, cobalt- and nickel-catalyzed ATH and AH of ketones are even seldom reported. In early 2004, we reported the first ATH of ketones with catalysts generated in situ from iron cluster complex and chiral PNNP ligand. Since then, we have devoted ourselves to the development of ATH and AH of ketones with iron, cobalt, and nickel catalysts containing novel chiral aminophosphine ligands. In our study, the iron catalyst containing chiral aminophosphine ligands, which are expected to control the stereochemistry at the metal atom, restrict the number of possible diastereoisomers, and effectively transfer chiral information, are successful catalysts for enantioselective reduction of ketones. Among these novel chiral aminophosphine ligands, 22-membered macrocycle P2N4

  14. RHIC operation with asymmetric collisions in 2015

    Energy Technology Data Exchange (ETDEWEB)

    Liu, C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Aschenauer, C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Atoian, G. [Brookhaven National Lab. (BNL), Upton, NY (United States); Blaskiewicz, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Brown, K. A. [Brookhaven National Lab. (BNL), Upton, NY (United States); Bruno, D. [Brookhaven National Lab. (BNL), Upton, NY (United States); Connolly, R. [Brookhaven National Lab. (BNL), Upton, NY (United States); Ottavio, T. D. [Brookhaven National Lab. (BNL), Upton, NY (United States); Drees, K. A. [Brookhaven National Lab. (BNL), Upton, NY (United States); Fischer, W. [Brookhaven National Lab. (BNL), Upton, NY (United States); Gardner, C. J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Gu, X. [Brookhaven National Lab. (BNL), Upton, NY (United States); Hayes, T. [Brookhaven National Lab. (BNL), Upton, NY (United States); Huang, H. [Brookhaven National Lab. (BNL), Upton, NY (United States); Laster, J. S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Luo, Y. [Brookhaven National Lab. (BNL), Upton, NY (United States); Makdisi, Y. [Brookhaven National Lab. (BNL), Upton, NY (United States); Marr, G. [Brookhaven National Lab. (BNL), Upton, NY (United States); Marusic, A. [Brookhaven National Lab. (BNL), Upton, NY (United States); Meot, F. [Brookhaven National Lab. (BNL), Upton, NY (United States); Mernick, K. [Brookhaven National Lab. (BNL), Upton, NY (United States); Michnoff, R. [Brookhaven National Lab. (BNL), Upton, NY (United States); Minty, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Montag, C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Morris, J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Narayan, G. [Brookhaven National Lab. (BNL), Upton, NY (United States); Nayak, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Nemesure, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Pile, P. [Brookhaven National Lab. (BNL), Upton, NY (United States); Poblaguev, A. [Brookhaven National Lab. (BNL), Upton, NY (United States); Ranjbar, V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Robert-Demolaize, G. [Brookhaven National Lab. (BNL), Upton, NY (United States); Roser, T. [Brookhaven National Lab. (BNL), Upton, NY (United States); Schmidke, B. [Brookhaven National Lab. (BNL), Upton, NY (United States); Schoefer, V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Severino, F. [Brookhaven National Lab. (BNL), Upton, NY (United States); Shrey, T. [Brookhaven National Lab. (BNL), Upton, NY (United States); Smith, K. [Brookhaven National Lab. (BNL), Upton, NY (United States); Steski, D. [Brookhaven National Lab. (BNL), Upton, NY (United States); Tepikian, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Trbojevic, D. [Brookhaven National Lab. (BNL), Upton, NY (United States); Tsoupas, N. [Brookhaven National Lab. (BNL), Upton, NY (United States); Wang, G. [Brookhaven National Lab. (BNL), Upton, NY (United States); White, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Yip, K. [Brookhaven National Lab. (BNL), Upton, NY (United States); Zaltsman, A. [Brookhaven National Lab. (BNL), Upton, NY (United States); Zeno, K. [Brookhaven National Lab. (BNL), Upton, NY (United States); Zhang, S. Y. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-08-07

    To study low-x shadowing/saturation physics as well as other nuclear effects [1], [2], proton-gold (p-Au, for 5 weeks) and proton-Aluminum (p-Al, for 2 weeks) collisions were provided for experiments in 2015 at the Relativistic Heavy Ion Collider (RHIC), with polarized proton beam in the Blue ring and Au/Al beam in the Yellow ring. The special features of the asymmetric run in 2015 will be introduced. The operation experience will be reviewed as well in the report.

  15. Massless sunset diagrams in finite asymmetric volumes

    Science.gov (United States)

    Niedermayer, F.; Weisz, P.

    2016-06-01

    This paper discusses the methods and the results used in an accompanying paper describing the matching of effective chiral Lagrangians in dimensional and lattice regularizations. We present methods to compute 2-loop massless sunset diagrams in finite asymmetric volumes in the framework of these regularizations. We also consider 1-loop sums in both regularizations, extending the results of Hasenfratz and Leutwyler for the case of dimensional regularization and we introduce a new method to calculate precisely the expansion coefficients of the 1-loop lattice sums.

  16. Success Factors of Asymmetric Connections - Example of Large Slovenian Enterprises

    Directory of Open Access Journals (Sweden)

    Viktor Vračar

    2014-11-01

    Full Text Available More and more companies realize the fact that networking or partner collaborations, which are based on partner relations between companies, are essential for their long-term existence. In today’s global competitive environment each company is included at least in some different connections. Very common connections occur between large and smaller enterprises, where the so called asymmetric connections occur, which may be understood as the ability of one organisation to establish power, influence and control over the other organisation and its resources. According to numerous statements, the connections between enterprises are very frequently uneffectivenessful, with opinions on the optimal nature of asymmetric connections being quite common as well, whereby it is, as a rule, a synergic complementing of missing content for both partners. To verify the thesis, that companies achieve more competitiveness and effectiveness through connections, whereby the so called asymmetric connections are common, a structural model of the evolution of asymmetric connection has been developed, which connects the theoretically identified factors and all dependent concepts of competitiveness, efficiency and effectiveness. The empirical research also attempts to further expose the factors of asymmetric connections, which affect efficiency and effectiveness of the connected enterprises.

  17. Thermal transport across symmetric and asymmetric solid-solid interfaces

    Science.gov (United States)

    Bi, Kedong; Liu, Yadong; Zhang, Chunwei; Li, Jiapeng; Chen, Minhua; Chen, Yunfei

    2016-10-01

    Thermal transport across symmetric and asymmetric solid-solid interfaces is investigated by non-equilibrium molecular dynamics simulations. For symmetric interfaces, simulation results demonstrate that the thermal interface resistance is reduced greatly with the temperature increasing from 20 to 70 K. Besides, the introduction of an interlayer in the region of a highly mismatched interface is predicted to effectively decrease the thermal interface resistance due to the vibrational bridge role of the interlayer in connecting two vibrationally mismatched materials. As for the case of asymmetric interfaces, it is found that the capacity of thermal transport across an asymmetric interface is related to the effective interfacial area, namely the smaller cross-section area of component materials. In addition, effects of the transition angle at asymmetric interfaces on the thermal interface resistance are further studied when heat flows through interfaces from the side with larger cross-section area to the other. It is shown that a smoother transition is preferred for thermal transport through an asymmetric interface.

  18. Asymmetric GaAs n-type double δ-doped quantum wells as a source of intersubband-related nonlinear optical response: Effects of an applied electric field

    Energy Technology Data Exchange (ETDEWEB)

    Rodríguez-Magdaleno, K.A.; Martínez-Orozco, J.C.; Rodríguez-Vargas, I. [Unidad Académica de Física, Universidad Autónoma de Zacatecas, Calz. Solidaridad Esq. Paseo a La Bufa S/N. C.P. 98060 Zacatecas (Mexico); Mora-Ramos, M.E. [Facultad de Ciencias, Universidad Autónoma del Estado de Morelos, Av. Universidad 1001, CP 62209 Cuernavaca, Morelos (Mexico); Física Teórica y Aplicada, Escuela de Ingeniería de Antioquia, AA 7516 Medellín (Colombia); Grupo de Materia Condensada-UdeA, Instituto de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín (Colombia); Duque, C.A., E-mail: cduque@fisica.udea.edu.co [Grupo de Materia Condensada-UdeA, Instituto de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín (Colombia)

    2014-03-15

    In this work, the conduction band electron states and the associated intersubband-related linear and nonlinear optical absorption coefficient and relative refractive index change are calculated for an asymmetric double n-type δ-doped quantum well in a GaAs-matrix. The effects of an external applied static electric field are included. Values of the two-dimensional impurities density (N{sub 2d}) of each single δ-doped quantum well are taken to vary within the range of 1.0×10{sup 12} to 7.0×10{sup 12} cm{sup −2}, consistent with the experimental data growth regime. The optical responses are reported as a function of the δ-doped impurities density and the applied electric field. It is shown that single electron states and the related optical quantities are significantly affected by the structural asymmetry of the double δ-doped quantum well system. In addition, a brief comparison with the free-carrier-related optical response is presented. -- Highlights: • Nonlinear optics in asymmetric double n-type δ-doped quantum well in a GaAs-matrix. • The system is considered under external applied electric field in growth direction. • The 2D impurity density is consistent with the experimental data growth regime. • The optical quantities are significantly affected by the structural asymmetry of the system.

  19. Asymmetric Multilevel Diversity Coding and Asymmetric Gaussian Multiple Descriptions

    CERN Document Server

    Mohajer, Soheil; Diggavi, Suhas N

    2009-01-01

    We consider the asymmetric multilevel diversity (A-MLD) coding problem, where a set of $2^K-1$ information sources, ordered in a decreasing level of importance, is encoded into $K$ messages (or descriptions). There are $2^K-1$ decoders, each of which has access to a non-empty subset of the encoded messages. Each decoder is required to reproduce the information sources up to a certain importance level depending on the combination of descriptions available to it. We obtain a single letter characterization of the achievable rate region for the 3-description problem. In contrast to symmetric multilevel diversity coding, source-separation coding is not sufficient in the asymmetric case, and ideas akin to network coding need to be used strategically. Based on the intuitions gained in treating the A-MLD problem, we derive inner and outer bounds for the rate region of the asymmetric Gaussian multiple description (MD) problem with three descriptions. Both the inner and outer bounds have a similar geometric structure t...

  20. Dosimetric characteristics of a 6 MV photon beam from a linear accelerator with asymmetric collimator jaws

    Energy Technology Data Exchange (ETDEWEB)

    Palta, J.R.; Ayyangar, K.M.; Suntharalingam, N.

    1988-02-01

    Dosimetric measurements have been made of a 6 MV photon beam from a linear accelerator equipped with asymmetric jaws. The field size factors for asymmetrically set fields are compared to those for symmetrically set fields. The change of beam quality has been measured as a function of off-axis position of the asymmetric fields to assess its effect on depth dose. Additional measurements include beam penumbra and shape of isodose curves for open and wedge fields as the field opening is moved asymmetrically from the central ray.

  1. Engineering Chiral Catalysts through Asymmetric Activation and Super High Throughput Screening (SHTS)

    Institute of Scientific and Technical Information of China (English)

    MIKAMI,Koichi; KORENAGA,Toshinobu; MATSUKAWA,Satoru; DING,Kui-Ling; LONG,Jiang

    2001-01-01

    A conceptually new strategy for asymmetric catalysis, namely asymmetric activation, in which a chiral activator selectively activates one enantiomer of a racemic chiral catalyst, and a highly efficient screening system for finding the most effective catalysts, namely super high throughput screening (SHTS), by which the reaction can be conducted in parallel and the ee% of the product is allowed to determine within minutes, are summarized in the present account. It is reasonable to be lieve that SHTS technique combined with asymmetric activa tion or deactivation principle will provide a very powerful methodology for finding the new catalysts and the best catalyst tuning for asymmetric reactions.

  2. Consumption Habit Preference,Monetary Expansion and the Asymmetric Effect of Output%货币扩张、消费习惯偏好与产出非对称效应研究

    Institute of Scientific and Technical Information of China (English)

    戴克明; 王莉; 许先普

    2015-01-01

    运用 LSTVAR 方法,考量货币扩张、消费习惯偏好与产出非对称效应,发现货币扩张的产出效应具有非对称性,且货币扩张在“低增长区制”下的产出效应显著大于在“高增长区制”下的产出效应。消费习惯偏好的程度差异是导致不同经济区制下货币政策非对称效应的主要原因,且低消费习惯偏好下货币扩张的产出效果更好。鉴此,政府在主动降低经济增速要求的同时,应积极创新宏观调控方式,改善居民消费环境,优化居民消费结构,以降低居民消费习惯偏好。%This paper analyzed the asymmetric effect of monetary policy on output by using LSTVAR model,and found that the output effect of monetary expansion in the low growth re- gime was significantly greater than the effect in the high growth regime.The research also showed that the difference of consumption habit preference was the main reason leading to asym-metric effect of monetary policy in different economic regime system,and the output effect of mo-netary expansion in low consumption habit preference regime will be better.Therefore,the gov-ernment should reduce the economic growth speed requirements,and pursue actively macro-con-trol innovation to improve the consumer environment and reduce the consumption habit prefer-ence.

  3. Cyclodextrins in Asymmetric and Stereospecific Synthesis

    Directory of Open Access Journals (Sweden)

    Fliur Macaev

    2015-09-01

    Full Text Available Since their discovery, cyclodextrins have widely been used as green and easily available alternatives to promoters or catalysts of different chemical reactions in water. This review covers the research and application of cyclodextrins and their derivatives in asymmetric and stereospecific syntheses, with their division into three main groups: (1 cyclodextrins promoting asymmetric and stereospecific catalysis in water; (2 cyclodextrins’ complexes with transition metals as asymmetric and stereospecific catalysts; and (3 cyclodextrins’ non-metallic derivatives as asymmetric and stereospecific catalysts. The scope of this review is to systematize existing information on the contribution of cyclodextrins to asymmetric and stereospecific synthesis and, thus, to facilitate further development in this direction.

  4. Ballistic thermal rectification in asymmetric three-terminal graphene nanojunctions

    Science.gov (United States)

    Ouyang, Tao; Chen, Yuanping; Xie, Yuee; Wei, X. L.; Yang, Kaike; Yang, Ping; Zhong, Jianxin

    2010-12-01

    Graphene nanojunctions (GNJs) are important components of future nanodevices and nanocircuits. Using the nonequilibrium Green’s function method, we investigate the phononic properties of three-terminal GNJs (TGNJs). The results show that the heat flux runs preferentially along the direction from narrow to wide terminals, presenting an evident ballistic thermal rectification effect in the asymmetric TGNJs. The rectification efficiency is strongly dependent on the asymmetry of the nanojunctions, which increases rapidly with the width discrepancy between the left and right terminals. Meanwhile, the corner form of the TGNJs also plays an important role in the rectification effect. The mechanism of this thermal rectification is explained by a qualitative analysis. Compared to previous thermal rectifiers based on other materials, the asymmetric nanojunctions based on graphene possess much high rectification ratio which can approach about 200%. These indicate that asymmetric TGNJs might be a promising candidate for excellent ballistic thermal (phononic) devices.

  5. Solitary waves in asymmetric electron-positron-ion plasmas

    Science.gov (United States)

    Lu, Ding; Li, Zi-Liang; Xie, Bai-Song

    2015-10-01

    > By solving the coupled equations of the electromagnetic field and electrostatic potential, we investigate solitary waves in an asymmetric electron-positron plasma and/or electron-positron-ion plasmas with delicate features. It is found that the solutions of the coupled equations can capture multipeak structures of solitary waves in the case of cold plasma, which are left out by using the long-wavelength approximation. By considering the effect of ion motion with respect to non-relativistic and ultra-relativistic temperature plasmas, we find that the ions' mobility can lead to larger-amplitude solitary waves; especially, this becomes more obvious for a high-temperature plasma. The effects of asymmetric temperature between electrons and positrons and the ion fraction on the solitary waves are also studied and presented. It is shown that the amplitudes of solitary waves decrease with positron temperature in asymmetric temperature electron-positron plasmas and decrease also with ion concentration.

  6. Asymmetric information and macroeconomic dynamics

    Science.gov (United States)

    Hawkins, Raymond J.; Aoki, Masanao; Roy Frieden, B.

    2010-09-01

    We show how macroeconomic dynamics can be derived from asymmetric information. As an illustration of the utility of this approach we derive the equilibrium density, non-equilibrium densities and the equation of motion for the response to a demand shock for productivity in a simple economy. Novel consequences of this approach include a natural incorporation of time dependence into macroeconomics and a common information-theoretic basis for economics and other fields seeking to link micro-dynamics and macro-observables.

  7. Entrepreneurship, Asymmetric Information and Unemployment

    OpenAIRE

    Robin Boadway; Nicolas Marceau; Maurice Marchand; Marianne Vigneault

    1998-01-01

    We examine how three sources of asymmetric information affect the supply of entrepreneurs and unemployment. In the first case, banks cannot observe entrepreneurs' risk of failure so ration credit. This increases the number of entrepreneurs and the level of unemployment. In the second case, firms cannot observe workers' effort so offer a wage above the market clearing one. This results in unemployment and too few entrepreneurs. The final case arises when firms cannot observe workers' abilities...

  8. Asymmetric Microscopic Driving Behavior Theory

    OpenAIRE

    Yeo, Hwasoo

    2008-01-01

    Numerous theories on traffic have been developed as traffic congestion gains more and more interest in our daily life. To model traffic phenomena, many traffic theorists have adopted theories from other fields such as fluid mechanics and thermodynamics. However, their efforts to model the traffic at a microscopic level have not been successful yet. Therefore, to overcome the limitations of the existing theories we propose a microscopic asymmetric traffic theory based on analysis of individual...

  9. Asymmetric exchange in flocks

    CERN Document Server

    Dadhichi, Lokrshi Prawar; Maitra, Ananyo; Ramaswamy, Sriram

    2016-01-01

    As the constituents of a flock are polar, one expects a fore-aft asymmetry in their interactions. We show here that the resulting antisymmetric part of the "exchange coupling" between a bird and its neighbours, if large enough, destabilizes the flock through spontaneous turning of the birds. The same asymmetry also yields a natural mechanism for a difference between the speed of advection of information along the flock and the speed of the flock itself. We show that the absence of detailed balance, and not merely the breaking of Galilean invariance, is responsible for this difference. We delineate the conditions on parameters and wavenumber for the existence of the turning instability. Lastly we present an alternative perspective based on flow-alignment effects in an active liquid crystal with turning inertia in contact with a momentum sink.

  10. 基于 ST AR 模型的中国货币政策对产出影响的非对称性研究%Asymmetric Effects of Monetary Shocks on Output Based on STAR Model

    Institute of Scientific and Technical Information of China (English)

    赵春艳; 程璐

    2014-01-01

    对中国GDP增长率建立以可预期到的货币冲击、未预期到的正向货币冲击和未预期到的负向货币冲击滞后三期为转移变量的LSTAR模型,拟合效果良好,分析不同类型的货币冲击对产出的非线性和非对称性影响,给出可预期到的货币冲击、未预期到的正向货币冲击和未预期到的负向货币冲击的阀值,分别为20.03%、2%和1.58%,说明不同类型的货币冲击对产出呈现不同的非对称性影响,强弱机制的转换区间存在差异,且负向货币冲击的阀值小于正向货币冲击的阀值。研究结果表明中国的货币政策存在显著的非线性和非对称性特征,且紧缩性货币政策比扩张性货币政策更有效。%In this paper ,the author makes the smooth transition auto regressive model (STAR) based on the growth rate of China's GDP ,and uses the expected positive and negative unexpected monetary shocks as transitional variables . T he imitative effect is good , and then it is show n that different of nonlinear and asymmetric influences are appeared among expected and unexpected monetary shocks .The threshold value can be used to measure the degree of the expected positive and negative unexpected monetary shocks ,20 .03% ,2% and 1 .58 respectively .It show s that there are some asymmetric effects of monetary shocks on output .The threshold value of negative unexpected monetary shocks is less than that of positive unexpected monetary shocks . The paper results shows that monetary policy is absolutely nolinear and asymmetric ,and the effect of tight -money policy is better than the easy monetary policy .

  11. Asymmetric Wettability Directs Leidenfrost Droplets

    Energy Technology Data Exchange (ETDEWEB)

    Agapov, Rebecca L [ORNL; Boreyko, Jonathan B [ORNL; Briggs, Dayrl P [ORNL; Srijanto, Bernadeta R [ORNL; Retterer, Scott T [ORNL; Collier, Pat [ORNL; Lavrik, Nickolay V [ORNL

    2014-01-01

    Leidenfrost phenomena on nano- and microstructured surfaces are of great importance for increasing control over heat transfer in high power density systems utilizing boiling phenomena. They also provide an elegant means to direct droplet motion in a variety of recently emerging fluidic systems. Here, we report the fabrication and characterization of tilted nanopillar arrays (TNPAs) that exhibit directional Leidenfrost water droplets under dynamic conditions, namely on impact with Weber numbers 40 at T 325 C. The batch fabrication of the TNPAs was achieved by glancing-angle anisotropic reactive ion etching of a thermally dewet platinum mask, with mean pillar diameters of 100 nm and heights of 200-500 nm. In contrast to previously implemented macro- and microscopic Leidenfrost ratchets, our TNPAs induce no preferential directional movement of Leidenfrost droplets under conditions approaching steady-state film boiling, suggesting that the observed droplet directionality is not a result of asymmetric vapor flow. Using high-speed imaging, phase diagrams were constructed for the boiling behavior upon impact for droplets falling onto TNPAs, straight nanopillar arrays, and smooth silicon surfaces. The asymmetric impact and directional trajectory of droplets was exclusive to the TNPAs for impacts corresponding to the transition boiling regime, revealing that asymmetric wettability upon impact is the mechanism for the droplet directionality.

  12. Properties of asymmetrically evolved community networks

    Institute of Scientific and Technical Information of China (English)

    Cui Di; Gao Zi-You; Zheng Jian-Feng

    2009-01-01

    This paper studies a simple asymmetrically evolved community network with a combination of preferential at-tachment and random properties. An important issue about community networks is to discover the different utility increments of two nodes, where the utility is introduced to investigate the asymmetrical effect of connecting two nodes. On the other hand, the connection of two nodes in community networks can be classified as two nodes belonging to the same or to different communities. The simulation results show that the model can reproduce a power-law utility distribution P(u)~ u-σ,σ=2+ 1/p, which can be obtained by using mean-field approximation methods. Furthermore, the model exhibits exponential behaviour with respect to small values of a parameter denoting the random effect in our model at the low-utility region and a power-law feature with respect to big values of this parameter at the high-utility region, which is in good agreement with theoretical analysis. This kind of community network can reproduce a unique utility distribution by theoretical and numerical analysis.

  13. Performance of JPEG Image Transmission Using Proposed Asymmetric Turbo Code

    Directory of Open Access Journals (Sweden)

    Siddiqi Mohammad Umar

    2007-01-01

    Full Text Available This paper gives the results of a simulation study on the performance of JPEG image transmission over AWGN and Rayleigh fading channels using typical and proposed asymmetric turbo codes for error control coding. The baseline JPEG algorithm is used to compress a QCIF ( "Suzie" image. The recursive systematic convolutional (RSC encoder with generator polynomials , that is, (13/11 in decimal, and 3G interleaver are used for the typical WCDMA and CDMA2000 turbo codes. The proposed asymmetric turbo code uses generator polynomials , that is, (13/11; 13/9 in decimal, and a code-matched interleaver. The effect of interleaver in the proposed asymmetric turbo code is studied using weight distribution and simulation. The simulation results and performance bound for proposed asymmetric turbo code for the frame length , code rate with Log-MAP decoder over AWGN channel are compared with the typical system. From the simulation results, it is observed that the image transmission using proposed asymmetric turbo code performs better than that with the typical system.

  14. Asymmetric chemical reactions by polarized quantum beams

    Science.gov (United States)

    Takahashi, Jun-Ichi; Kobayashi, Kensei

    One of the most attractive hypothesis for the origin of homochirality in terrestrial bio-organic compounds (L-amino acid and D-sugar dominant) is nominated as "Cosmic Scenario"; a chiral impulse from asymmetric excitation sources in space triggered asymmetric reactions on the surfaces of such space materials as meteorites or interstellar dusts prior to the existence of terrestrial life. 1) Effective asymmetric excitation sources in space are proposed as polarized quantum beams, such as circularly polarized light and spin polarized electrons. Circularly polarized light is emitted as synchrotron radiation from tightly captured electrons by intense magnetic field around neutron stars. In this case, either left-or right-handed polarized light can be observed depending on the direction of observation. On the other hand, spin polarized electrons is emitted as beta-ray in beta decay from radioactive nuclei or neutron fireballs in supernova explosion. 2) The spin of beta-ray electrons is longitudinally polarized due to parity non-conservation in the weak interaction. The helicity (the the projection of the spin onto the direction of kinetic momentum) of beta-ray electrons is universally negative (left-handed). For the purpose of verifying the asymmetric structure emergence in bio-organic compounds by polarized quantum beams, we are now carrying out laboratory simulations using circularly polarized light from synchrotron radiation facility or spin polarized electron beam from beta-ray radiation source. 3,4) The target samples are solid film or aqueous solution of racemic amino acids. 1) K.Kobayashi, K.Kaneko, J.Takahashi, Y.Takano, in Astrobiology: from simple molecules to primitive life; Ed. V.Basiuk; American Scientific Publisher: Valencia, 2008. 2) G.A.Gusev, T.Saito, V.A.Tsarev, A.V.Uryson, Origins Life Evol. Biosphere. 37, 259 (2007). 3) J.Takahashi, H.Shinojima, M.Seyama, Y.Ueno, T.Kaneko, K.Kobayashi, H.Mita, M.Adachi, M.Hosaka, M.Katoh, Int. J. Mol. Sci. 10, 3044

  15. New Asymmetric Fuzzy PID Control for Pneumatic Position Control System

    Institute of Scientific and Technical Information of China (English)

    薛阳; 彭光正; 范萌; 伍清河

    2004-01-01

    A fuzzy control algorithm of asymmetric fuzzy strategy is introduced for a servo-pneumatic position system. It can effectively solve the difficult problems of single rod low friction cylinders, which are mainly caused by asymmetric structures and different friction characteristics in two directions. On the basis of this algorithm, a traditional PID control is used to improve dynamic performance. Furthermore, a new asymmetric fuzzy PID control with α factor is advanced to improve the self-adaptability and robustness of the system. Both the theoretical analyses and experimental results prove that, with this control strategy, the dynamic performance of the system can be greatly improved. The system using this control algorithm has strong robustness and it obtains desired overshoot and repeatability in both transient and steady-state responses.

  16. Spectroscopic calculation of asymmetric top free radicals: method and program

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    This paper sketches out the effective Hamiltonian and basis set adopted in the spectroscopic calcula tion of asymmetric top free radicals, and details the machine implementation of the spectral analysis of asymmetric top free radicals, the design and usage of the program package. To demonstrate the application of this program, analyses have been performed on the far infrared laser magnetic resonance spectrum of 14N16O2( I = 1) and the infrared diode laser spectrum of the v3 band of PO2( I = 1/2) using the program.

  17. Developing a Practical Chiral Toolbox for Asymmetric Catalytic Reactions

    Institute of Scientific and Technical Information of China (English)

    ZHANG; XuMu

    2001-01-01

    Chiral Quest's Toolbox Approach: During the last several decades, chemists have made major progress in discovering man-made catalysts to perform challenging asymmetric transformations. However, there is no universal chiral ligand or catalyst for solving problems in enantioselective transformations. The focus of Chiral Quest's research is to develop a useful chiral toolbox for strategically important asymmetric catalytic reactions by inventing a diverse set of novel chiral ligands and combining them with transition metals as effective enantioselective catalysts. The toolbox approach addresses significant problems in organic stereochemistry and has resulted in practical methods for the synthesis of chiral pharmaceuticals and agrochemicals  ……

  18. Developing a Practical Chiral Toolbox for Asymmetric Catalytic Reactions

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@ Chiral Quest's Toolbox Approach: During the last several decades, chemists have made major progress in discovering man-made catalysts to perform challenging asymmetric transformations. However, there is no universal chiral ligand or catalyst for solving problems in enantioselective transformations. The focus of Chiral Quest's research is to develop a useful chiral toolbox for strategically important asymmetric catalytic reactions by inventing a diverse set of novel chiral ligands and combining them with transition metals as effective enantioselective catalysts. The toolbox approach addresses significant problems in organic stereochemistry and has resulted in practical methods for the synthesis of chiral pharmaceuticals and agrochemicals

  19. Careful numerical study of flowfields about asymmetric external conical corners

    Science.gov (United States)

    Salas, M. D.

    1980-01-01

    A numerical study of the flowfield about asymmetrical external axial corners formed by the juncture of swept compressive wedges is presented. The geometrical configuration allows a unified treatment of external corners typical of delta wings and rectangular inlets. The study investigates how the flow transitions from a symmetrical flowfield with a cross-flow stagnation point at the corner to an asymmetrical flowfield for which the flow spills over the corner. The effects of leading-edge sweep, wedge compression, and corner radius are investigated.

  20. Dynamic JUNQ inclusion bodies are asymmetrically inherited in mammalian cell lines through the asymmetric partitioning of vimentin.

    Science.gov (United States)

    Ogrodnik, Mikołaj; Salmonowicz, Hanna; Brown, Rachel; Turkowska, Joanna; Średniawa, Władysław; Pattabiraman, Sundararaghavan; Amen, Triana; Abraham, Ayelet-chen; Eichler, Noam; Lyakhovetsky, Roman; Kaganovich, Daniel

    2014-06-01

    Aging is associated with the accumulation of several types of damage: in particular, damage to the proteome. Recent work points to a conserved replicative rejuvenation mechanism that works by preventing the inheritance of damaged and misfolded proteins by specific cells during division. Asymmetric inheritance of misfolded and aggregated proteins has been shown in bacteria and yeast, but relatively little evidence exists for a similar mechanism in mammalian cells. Here, we demonstrate, using long-term 4D imaging, that the vimentin intermediate filament establishes mitotic polarity in mammalian cell lines and mediates the asymmetric partitioning of damaged proteins. We show that mammalian JUNQ inclusion bodies containing soluble misfolded proteins are inherited asymmetrically, similarly to JUNQ quality-control inclusions observed in yeast. Mammalian IPOD-like inclusion bodies, meanwhile, are not always inherited by the same cell as the JUNQ. Our study suggests that the mammalian cytoskeleton and intermediate filaments provide the physical scaffold for asymmetric inheritance of dynamic quality-control JUNQ inclusions. Mammalian IPOD inclusions containing amyloidogenic proteins are not partitioned as effectively during mitosis as their counterparts in yeast. These findings provide a valuable mechanistic basis for studying the process of asymmetric inheritance in mammalian cells, including cells potentially undergoing polar divisions, such as differentiating stem cells and cancer cells.

  1. Effects of MEK inhibitor U0126 on meiotic progression in mouse oocytes:microtuble organization, asymmetric division and metaphase Ⅱ arrest

    Institute of Scientific and Technical Information of China (English)

    JIAN WEN DONG; HAl FENG ZHU; WEI ZHONG ZHU; HAI LEI DING; TIE MIN MA; ZHAO NIAN ZHOU

    2003-01-01

    In this study we used U0126, a potent and specific inhibitor of MEK, to study the roles of MEK/ERK/p90rsk signaling pathway in the meiotic cell cycle of mouse oocytes. The phosphorylation of MAP kinase and p90rsk in the oocytes treated with 1.5 μMU0126 was the same as that in oocytes cultured in drug-free medium. With 1.5 μM U0126 treatment, the spindles appeared normal as they formed in oocytes, but failed to maintain its structure.Instead, the spindle lost one pole or elongated extraordinarily. After further culture, some oocytes extruded gigantic polar bodies (>30 μm) that later divided into two small ones. Some oocytes underwent symmetric division and produced two equal-size daughter cells in which normal spindles formed. In oocytes with different division patterns,MAP kinase was normally phosphorylated. When the concentration of U0126 was increased to 15 mM, the phosphorylation of both MAPK and p90rsk were inhibited, while symmetric division was decreased. When incubating in medium containing 15 μM U0126 for 14 h, oocytes were activated, but part of them failed to emit polar bodies. MII oocytes were also activated by 15 μM U0126, at the same time the dephosphorylation of MAP kinase and p90rsk was observed. Our results indicate that 1) MEK plays important but not indispensable roles in microtubule organization;2) MEK keeps normal meiotic spindle morphology, targets peripheral spindle positioning and regulates asymmetric division by activating some unknown substrates other than MAP kinase/p90rsk; and 3) activation of MEK/ERK/p90rsk cascade maintains MII arrest in mouse oocytes.

  2. Phase diagram of highly asymmetric binary hardsphere mixtures

    NARCIS (Netherlands)

    Dijkstra, M.; van Roij, R.H.H.G.; Evans, R.

    1999-01-01

    We study the phase behavior and structure of highly asymmetric binary hard-sphere mixtures. By first integrating out the degrees of freedom of the small spheres in the partition function we derive a formal expression for the effective Hamiltonian of the large spheres. Then using an explicit pairwise

  3. Market Efficiency and Price Formation When Dealers are Asymmetrically Informed

    NARCIS (Netherlands)

    Calcagno, R.; Lovo, S.M.

    2002-01-01

    We consider the effect of asymmetric information on the price formation process in a quote-driven market where one market maker receives a private signal on the security fundamental.A model is presented where market makers repeatedly compete in prices: at each stage a bid-ask auction occurs and the

  4. Loss aversion and the asymmetric transmission of monetary policy

    NARCIS (Netherlands)

    Gaffeo, E.; Petrella, I.; Pfajfar, D.; Santoro, E.

    2014-01-01

    There is widespread evidence that monetary policy exerts asymmetric effects on output over contractions and expansions in economic activity, while price responses display no sizeable asymmetry. To rationalize these facts we develop a dynamic general equilibrium model where households’ utility depend

  5. Asymmetric Modulation Gains in Network Coded Relay Networks

    DEFF Research Database (Denmark)

    Roetter, Daniel Enrique Lucani; Fitzek, Frank

    2015-01-01

    –to–end throughput by (i) using network coding to control the use of the relay in an effective manner, and (ii) leveraging asymmetric modulation to enable the source to efficiently allocate its resources. We provide mathematical analysis and a simple optimization mechanism. Numerical results for the case of fading...

  6. Attempt to accelerate asymmetric species with unequal frequencies in RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Liu, C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Luo, Y. [Brookhaven National Lab. (BNL), Upton, NY (United States); Marusic, A. [Brookhaven National Lab. (BNL), Upton, NY (United States); Minty, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Robert-Demolaize, G. [Brookhaven National Lab. (BNL), Upton, NY (United States); Smith, K. [Brookhaven National Lab. (BNL), Upton, NY (United States); Mernick, K. [Brookhaven National Lab. (BNL), Upton, NY (United States); Hayes, T. [Brookhaven National Lab. (BNL), Upton, NY (United States); Severino, F. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-07-09

    This report summarizes the beam studies on accelerating asymmetric beams with unequal frequencies, during the proton-Gold/Aluminum run in 2015. The experiment failed due to modulated beam-beam effects even though the beams were separated by at least 15 mm.

  7. Asymmetric Information and Consumer Demand

    OpenAIRE

    Ismagilova G. N.; Danilina E. I.; Gafurov I. R.; Ismagilov R. I.; Safiullin L. N.

    2014-01-01

    In the paper study the peculiarities of the formation the consumer demand for durable goods, the so-called «experience goods» in markets with asymmetric information. In the known literature sources studying of the demand is based on the assumption that at the moment of the purchase of goods and services people know exactly what price they are willing to pay for them and what utility they are going to obtain using those goods and services. Consider the signal model in which the initial price a...

  8. Asymmetric Formal Synthesis of Azadirachtin.

    Science.gov (United States)

    Mori, Naoki; Kitahara, Takeshi; Mori, Kenji; Watanabe, Hidenori

    2015-12-01

    An asymmetric formal synthesis of azadirachtin, a potent insect antifeedant, was accomplished in 30 steps to Ley's synthetic intermediate (longest linear sequence). The synthesis features: 1) rapid access to the optically active right-hand segment starting from the known 5-hydroxymethyl-2-cyclopentenone scaffold; 2) construction of the B and E rings by a key intramolecular tandem radical cyclization; 3) formation of the hemiacetal moiety in the C ring through the α-oxidation of the six-membered lactone followed by methanolysis. PMID:26474211

  9. Transient Stability During Asymmetrical Faults

    OpenAIRE

    Couturier, Nicolas

    2015-01-01

    This research project has been conducted at RTE in order to study the transient stability after asymmetrical faults. When three-phase short-circuits occur in a network, almost all the electrical power is lost on the relevant line(s). Among all short-circuit types, it is the most drastic event and the issue has to be solved very quickly. But oddly, it is also the easiest problem to solve mathematically speaking. This comes from the fact that the system stays balanced, and equations can be simp...

  10. Enhanced Asymmetric Bilinear Model for Face Recognition

    OpenAIRE

    Wenjuan Gong; Weishan Zhang; Jordi Gonzàlez; Yan Ren; Zhen Li

    2015-01-01

    Bilinear models have been successfully applied to separate two factors, for example, pose variances and different identities in face recognition problems. Asymmetric model is a type of bilinear model which models a system in the most concise way. But seldom there are works exploring the applications of asymmetric bilinear model on face recognition problem with illumination changes. In this work, we propose enhanced asymmetric model for illumination-robust face recognition. Instead of initiali...

  11. Asymmetric Laguerre-Gaussian beams

    Science.gov (United States)

    Kovalev, A. A.; Kotlyar, V. V.; Porfirev, A. P.

    2016-06-01

    We introduce a family of asymmetric Laguerre-Gaussian (aLG) laser beams. The beams have been derived via a complex-valued shift of conventional LG beams in the Cartesian plane. While propagating in a uniform medium, the first bright ring of the aLG beam becomes less asymmetric and the energy is redistributed toward peripheral diffraction rings. The projection of the orbital angular momentum (OAM) onto the optical axis is calculated. The OAM is shown to grow quadratically with increasing asymmetry parameter of the aLG beam, which equals the ratio of the shift to the waist radius. Conditions for the OAM becoming equal to the topological charge have been derived. For aLG beams with zero radial index, we have deduced an expression to define the intensity maximum coordinates and shown the crescent-shaped intensity pattern to rotate during propagation. Results of the experimental generation and rotation of aLG beams agree well with theoretical predictions.

  12. Asymmetric Wettability Directs Leidenfrost Droplets

    Science.gov (United States)

    Agapov, Rebecca; Boreyko, Jonathan; Briggs, Dayrl; Srijanto, Bernadeta; Retterer, Scott; Collier, C. Patrick; Lavrik, Nickolay

    2014-03-01

    Exploration of Leidenfrost droplets on nano- and microstructured surfaces are of great importance for increasing control over heat transfer in high power density systems using boiling phenomena. They also provide an elegant way to direct droplet motion in a variety of emerging fluidic systems. Here, we report the fabrication and characterization of tilted nanopillar arrays (TNPAs) that exhibit directional Leidenfrost water droplets under dynamic conditions. The batch fabrication of the TNPAs was achieved by glancing-angle anisotropic reactive ion etching of a thermally dewet platinum mask. In contrast to previously implemented macro- and microscopic Leidenfrost ratchets, our TNPAs induce no preferential directional movement of Leidenfrost droplets under conditions approaching steady-state film boiling. This suggests that the observed droplet directionality is not a result of asymmetric vapor flow. Phase diagrams were constructed for the boiling behavior upon droplet impact onto TNPAs, straight nanopillar arrays, and smooth silicon surfaces. Asymmetric wettability and directional trajectory of droplets was exclusive to the TNPAs for impacts corresponding to the transition boiling regime, revealing this to be the mechanism for the droplet directionality. This work was conducted at the Center for Nanophase Materials Sciences, which is sponsored at Oak Ridge National Lab by the Division of Scientific User Facilities, US Dept. of Energy.

  13. Some Remarks on Asymmetric Syntheses from Recent Studies

    OpenAIRE

    Baba, Naomichi

    1990-01-01

    Some asymmetric syntheses were presented here and discussed briefly including NADH model reactions, phase transfer-catalyzed asymmetric epoxidation, enantiotopic group-selective hydrolysis of a malonic anhydride with alkoxide anion, intramolecular acid-catalyzed lactonizations, catalytic asymmetric Diels-Alder synthesis, asymmetric aldol condensation, chiral homoallyl alcohol synthesis, asymmetric addition of diethylzinc to aldehyde, kinetic resolution of racemic hydroperoxides and binaphthol...

  14. Investigation on the chirality of electrons from /sup 90/Sr-/sup 90/Y beta-decay and their asymmetrical interactions with D- and L-alanines

    Energy Technology Data Exchange (ETDEWEB)

    Conte, E.

    1985-12-16

    An investigation on the chirality of the electrons from /sup 90/Sr-/sup 90/Y beta decay and on their asymmetrical interactions with D- and L-alanines was carried out. By using ESR measurements, the asymmetrical yields were proved to be induced in /sup 90/Sr-/sup 90/Y-beta-irradiated alanines, with a distinguishably asymmetrical effect.

  15. The effects of the electric and intense laser field on the binding energies of donor impurity states (1s and 2p±) and optical absorption between the related states in an asymmetric parabolic quantum well

    Science.gov (United States)

    Kasapoglu, E.; Sakiroglu, S.; Sökmen, I.; Restrepo, R. L.; Mora-Ramos, M. E.; Duque, C. A.

    2016-10-01

    We have calculated the effects of electric and intense laser fields on the binding energies of the ground and some excited states of conduction electrons coupled to shallow donor impurities as well as the total optical absorption coefficient for transitions between 1s and 2p± electron-impurity states in a asymmetric parabolic GaAs/Ga1-x AlxAs quantum well. The binding energies were obtained using the effective-mass approximation within a variational scheme. Total absorption coefficient (linear and nonlinear absorption coefficient) for the transitions between any two impurity states were calculated from first- and third-order dielectric susceptibilities derived within a perturbation expansion for the density matrix formalism. Our results show that the effects of the electric field, intense laser field, and the impurity location on the binding energy of 1s-impurity state are more pronounced compared with other impurity states. If the well center is changed to be Lc0), the effective well width decreases (increases), and thus we can obtain the red or blue shift in the resonant peak position of the absorption coefficient by changing the intensities of the electric and non-resonant intense laser field as well as dimensions of the well and impurity positions.

  16. Isospin violating dark matter being asymmetric

    CERN Document Server

    Okada, Nobuchika

    2013-01-01

    The isospin violating dark matter (IVDM) scenario offers an interesting possibility to reconcile conflicting results among direct dark matter search experiments for a mass range around 10 GeV. We consider two simple renormalizable IVDM models with a complex scalar dark matter and a Dirac fermion dark matter, respectively, whose stability is ensured by the conservation of "dark matter number". Although both models successfully work as the IVDM scenario with destructive interference between effective couplings to proton and neutron, the dark matter annihilation cross section is found to exceed the cosmological/astrophysical upper bounds. Then, we propose a simple scenario to reconcile the IVDM scenario with the cosmological/astrophysical bounds, namely, the IVDM being asymmetric. Assuming a suitable amount of dark matter asymmetry has been generated in the early Universe, the annihilation cross section beyond the cosmological/astrophysical upper bound nicely works to dramatically reduce the anti-dark matter rel...

  17. Micropolarity Ramification of Asymmetric Merging Flow

    CERN Document Server

    Siddiqui, Abuzar Abid

    2016-01-01

    The steady, asymmetric and two-dimensional flow of viscous, incompressible micropolar fluid through a rectangular channel with a splitter (parallel to walls) was formulated and simulated numerically. The plane Poiseuille flow was considered far from upstream and downstream of the splitter. The geometric parameter that controls the position of splitter was defined as splitter position parameter. A numerical scheme that comprises a fourth order method followed by special finite-difference method was used to solve the boundary value problem. This numerical scheme transforms the governing equations to system of finite difference equations which we have solved by SOR iterative method. Moreover, the results obtained were further refined and upgraded by the Richardson extrapolation method. The results were compared on different grid sizes as well as with the existing results for symmetric flow of Newtonian fluids. The comparisons were satisfactory. The microrotation effects on the splitter plate were significantly h...

  18. Chilly Dark Sectors and Asymmetric Reheating

    CERN Document Server

    Adshead, Peter; Shelton, Jessie

    2016-01-01

    In a broad class of theories, the relic abundance of dark matter is determined by interactions internal to a thermalized dark sector, with no direct involvement of the Standard Model (SM). We point out that these theories raise an immediate cosmological question: how was the dark sector initially populated in the early universe? Motivated in part by the difficulty of accommodating large amounts of entropy carried in dark radiation with cosmic microwave background measurements of the effective number of relativistic species at recombination, $N_{\\mathrm{eff}}$, we aim to establish which admissible cosmological histories can populate a thermal dark sector that never reaches thermal equilibrium with the SM. The minimal cosmological origin for such a dark sector is asymmetric reheating, when the same mechanism that populates the SM in the early universe also populates the dark sector at a lower temperature. Here we demonstrate that the resulting inevitable inflaton-mediated scattering between the dark sector and ...

  19. Seismic Responses of Asymmetric Base-Isolated Structures under Near-Fault Ground Motion

    Institute of Scientific and Technical Information of China (English)

    YE Kun; LI Li; FANG Qin-han

    2008-01-01

    An inter-story shear model of asymmetric base-isolated structures incorporating deformation of each isolation bearing was built, and a method to simultaneously simulate bi-directional near-fault and far-field ground motions was proposed. A comparative study on the dynamic responses of asymmetric base-isolated structures under near-fault and far-field ground motions were conducted to investigate the effects of eccentricity in the isolation system and in the superstructures, the ratio of the uncoupled torsional to lateral frequency of the superstructure and the pulse period of near-fault ground motions on the nonlinear seismic response of asymmetric base-isolated structures. Numerical results show that eccentricity in the isolation system makes asymmetric base-isolated structure more sensitive to near-fault ground motions, and the pulse period of near-fault ground motions plays an import role in governing the seismic responses of asymmetric base-isolated structures.

  20. Tunable dual-band asymmetric transmission for circularly polarized waves with graphene planar chiral metasurfaces.

    Science.gov (United States)

    Li, Zhancheng; Liu, Wenwei; Cheng, Hua; Chen, Shuqi; Tian, Jianguo

    2016-07-01

    The asymmetric transmission effect has attracted great interest due to its wide modern optical applications. In this Letter, we present the underlying theory, the design specifications, and the simulated demonstration of tunable dual-band asymmetric transmission for circularly polarized waves with a graphene planar chiral metasurface. The spectral position of the asymmetric peak is linearly dependent on the Fermi energy and can be controlled by changing the Fermi energy. The success of tunable dual-band asymmetric transmission can be attributed to the enantiomerically sensitive plasmonic excitations of the graphene metasurface. This work offers a further step in developing tunable asymmetric transmission of circularly polarized waves for applications in detectors and other polarization-sensitive electromagnetic devices. PMID:27367122

  1. New asymmetric quantum codes over Fq

    Science.gov (United States)

    Ma, Yuena; Feng, Xiaoyi; Xu, Gen

    2016-07-01

    Two families of new asymmetric quantum codes are constructed in this paper. The first family is the asymmetric quantum codes with length n=qm-1 over Fq, where qge 5 is a prime power. The second one is the asymmetric quantum codes with length n=3m-1. These asymmetric quantum codes are derived from the CSS construction and pairs of nested BCH codes. Moreover, let the defining set T1=T2^{-q}, then the real Z-distance of our asymmetric quantum codes are much larger than δ _max+1, where δ _max is the maximal designed distance of dual-containing narrow-sense BCH code, and the parameters presented here have better than the ones available in the literature.

  2. Quality Prediction of Asymmetrically Distorted Stereoscopic 3D Images.

    Science.gov (United States)

    Wang, Jiheng; Rehman, Abdul; Zeng, Kai; Wang, Shiqi; Wang, Zhou

    2015-11-01

    Objective quality assessment of distorted stereoscopic images is a challenging problem, especially when the distortions in the left and right views are asymmetric. Existing studies suggest that simply averaging the quality of the left and right views well predicts the quality of symmetrically distorted stereoscopic images, but generates substantial prediction bias when applied to asymmetrically distorted stereoscopic images. In this paper, we first build a database that contains both single-view and symmetrically and asymmetrically distorted stereoscopic images. We then carry out a subjective test, where we find that the quality prediction bias of the asymmetrically distorted images could lean toward opposite directions (overestimate or underestimate), depending on the distortion types and levels. Our subjective test also suggests that eye dominance effect does not have strong impact on the visual quality decisions of stereoscopic images. Furthermore, we develop an information content and divisive normalization-based pooling scheme that improves upon structural similarity in estimating the quality of single-view images. Finally, we propose a binocular rivalry-inspired multi-scale model to predict the quality of stereoscopic images from that of the single-view images. Our results show that the proposed model, without explicitly identifying image distortion types, successfully eliminates the prediction bias, leading to significantly improved quality prediction of the stereoscopic images. PMID:26087491

  3. Application of density dependent parametrization models to asymmetric nuclear matter

    International Nuclear Information System (INIS)

    Density dependent parametrization models of the nucleon-meson effective couplings, including the isovector scalar δ-field, are applied to asymmetric nuclear matter. The nuclear equation of state and the neutron star properties are studied in an effective Lagrangian density approach, using the relativistic mean field hadron theory. It is known that the introduction of a δ-meson in the constant coupling scheme leads to an increase of the symmetry energy at high density and so to larger neutron star masses, in a pure nucleon-lepton scheme. We use here a more microscopic density dependent model of the nucleon-meson couplings to study the properties of neutron star matter and to reexamine the δ-field effects in asymmetric nuclear matter. Our calculations show that, due to the increase of the effective δ coupling at high density, with density dependent couplings the neutron star masses in fact can be even reduced

  4. Asymmetric facial skin viscoelasticity during climacteric aging

    Directory of Open Access Journals (Sweden)

    Piérard GE

    2014-04-01

    Full Text Available Gérald E Piérard,1 Trinh Hermanns-Lê,1 Ulysse Gaspard,2 Claudine Piérard-Franchimont11Laboratory of Skin Bioengineering and Imaging, Department of Clinical Sciences, University of Liège, 2Department of Gynecology and Obstetrics, University Hospital of Liège, Liège, BelgiumBackground: Climacteric skin aging affects certain biophysical characteristics of facial skin. The purpose of the present study was to assess the symmetric involvement of the cheeks in this stage of the aging process.Methods: Skin viscoelasticity was compared on both cheeks in premenopausal and post-menopausal women with indoor occupational activities somewhat limiting the influence of chronic sun exposure. Eighty-four healthy women comprising 36 premenopausal women and 48 early post-menopausal women off hormone replacement therapy were enrolled in two groups. The tensile characteristics of both cheeks were tested and compared in each group. A computerized suction device equipped with a 2 mm diameter hollow probe was used to derive viscoelasticity parameters during a five-cycle procedure of 2 seconds each. Skin unfolding, intrinsic distensibility, biological elasticity, and creep extension were measured.Results: Both biological elasticity and creep extension were asymmetric on the cheeks of the post-menopausal women. In contrast, these differences were more discrete in the premenopausal women.Conclusion: Facial skin viscoelasticity appeared to be asymmetric following menopause. The possibility of asymmetry should be taken into account in future studies of the effects of hormone replacement therapy and any antiaging procedure on the face in menopausal women.Keywords: climacteric aging, biomechanics, photoaging, skin unfolding, biological elasticity, skin tensile properties

  5. Influence of Frequency and Bias Current on Asymmetrical GMI Effect in Co71.8Fe4.9Nb0.8Si7.5B15 Amorphous Glass-Covered Wires

    Institute of Scientific and Technical Information of China (English)

    CHEN Zheng; LI De-ren; LU Zhi-chao; ZHOU Shao-xiong

    2008-01-01

    The 71.8Fe4.9Nb0.8Si7.5B15 amorphous glass-covered wires (AGCW) are prepared by the Taylor-Ulitovsky technique. The frequency dependence of asymmetrical giant magneto-impedance (AGMI) effect in amorphous glass-covered wires annealed by 70 mA DC current is here presented. The resistance R and the reactance X have been measured, respectively. The real part R and the imaginary part X of impedance play an important role at high frequency and low frequency, respectively. The influence of DC bias current from Ib=0 mA to Ib=5 mA at 30 MHz on the GMI effect in the glass-covered wires annealed by 70 mA DC current is investigated. The asymmetry becomes the largest around Ib = 1 mA, and finally decreases for the larger bias current Ib =5 mA. The maximum △Z/Z ratio of 310% is observed at 58 MHz under 1 mA bias current.

  6. Spectral Analysis for an Asymmetrical Structure Considering Soil Structure Interaction

    OpenAIRE

    Olariu, Cerasela Panseluța; Movilă, Mihaela

    2014-01-01

    In civil engineering, problems which deal with the effects of the structural asymmetry are more frequently encountered. Besides the fact that the majority of the design provisions recommend that the structure should be symmetrical in plane as well as in elevation, there are various situations in which asymmetrical structures are designed. The torsional response of these types of structures can be influenced also by taking into consideration the soil structure interaction effects. The...

  7. A computational study of asymmetric glottal jet deflection during phonation.

    Science.gov (United States)

    Zheng, X; Mittal, R; Bielamowicz, S

    2011-04-01

    Two-dimensional numerical simulations are used to explore the mechanism for asymmetric deflection of the glottal jet during phonation. The model employs the full Navier-Stokes equations for the flow but a simple laryngeal geometry and vocal-fold motion. The study focuses on the effect of Reynolds number and glottal opening angle with a particular emphasis on examining the importance of the so-called "Coanda effect" in jet deflection. The study indicates that the glottal opening angle has no substantial effect on glottal jet deflection. Deflection in the glottal jet is always preceded by large-scale asymmetry in the downstream portion of the glottal jet. A detailed analysis of the velocity and vorticity fields shows that these downstream asymmetric vortex structures induce a flow at the glottal exit which is the primary driver for glottal jet deflection. PMID:21476669

  8. Uniform versus asymmetric shading mediates crown recession in conifers.

    Directory of Open Access Journals (Sweden)

    Amanda L Schoonmaker

    Full Text Available In this study we explore the impact of asymmetrical vs. uniform crown shading on the mortality and growth of upper and lower branches within tree crowns, for two conifer species: shade intolerant lodgepole pine (Pinus contorta and shade tolerant white spruce (Picea glauca. We also explore xylem hydraulics, foliar nutrition, and carbohydrate status as drivers for growth and expansion of the lower and upper branches in various types of shading. This study was conducted over a two-year period across 10 regenerating forest sites dominated by lodgepole pine and white spruce, in the lower foothills of Alberta, Canada. Trees were assigned to one of four shading treatments: (1, complete uniform shading of the entire tree, (2 light asymmetric shading where the lower 1/4-1/3 of the tree crown was shaded, (3 heavy asymmetric shading as in (2 except with greater light reduction and (4 control in which no artificial shading occurred and most of the entire crown was exposed to full light. Asymmetrical shading of only the lower crown had a larger negative impact on the bud expansion and growth than did uniform shading, and the effect was stronger in pine relative to spruce. In addition, lower branches in pine also had lower carbon reserves, and reduced xylem-area specific conductivity compared to spruce. For both species, but particularly the pine, the needles of lower branches tended to store less C than upper branches in the asymmetric shade, which could suggest a movement of reserves away from the lower branches. The implications of these findings correspond with the inherent shade tolerance and self-pruning behavior of these conifers and supports a carbon based mechanism for branch mortality--mediated by an asymmetry in light exposure of the crown.

  9. Zinc supplementation in infants with asymmetric intra uterine growth retardation; effect on growth, nutritional status and leptin secretion Suplementación con zinc en niños con retraso de crecimiento intra-uterino asimétrico; efecto en el crecimiento, estado nutricional y secreción de leptina

    OpenAIRE

    O. Bueno; Bueno, G; Moreno, L.A.; R. J. Nuviala; J. M. Pérez-González; Bueno, M

    2008-01-01

    Objectives: To analyse the effect of zinc supplementation in growth and nutritional status of a homogeneous group of newborns with intra uterine growth retardation and asymmetric growth. The effect of changes of zinc status on growth and leptin serum concentrations was also analysed. Population and methods: A double blind, randomised clinical trial was designed in order to detect differences in growth between zinc and placebo groups during the first 6 months of life. 31 infants were included ...

  10. Nonlinear optical rectification and optical absorption in GaAs-Ga1-xAlxAs asymmetric double quantum wells: Combined effects of applied electric and magnetic fields and hydrostatic pressure

    International Nuclear Information System (INIS)

    The intersubband electron-related nonlinear optical absorption and nonlinear optical rectification in GaAs-Ga1-xAlxAs asymmetric double quantum wells are studied, under the influence of combined or independent applied electric and magnetic fields as well as hydrostatic pressure. The outcome of the density matrix formalism and the effective mass, and parabolic-band approximations have been considered as main theoretical tools for the description. It is obtained that under particular geometrical conditions, with or without electric and/or magnetic field strength, the optical rectification is null and, simultaneously, in such circumstances the optical absorption has a relative maximum. It is also detected that the influence of the hydrostatic pressure leads to increasing or decreasing behaviors of the nonlinear optical absorption in dependence of the particular regime of pressure values considered, with significant distinction of the cases of opposite electric field orientations. - Highlights: → Maxima of the NOA correspond to zero in the NOR. → Electric fields can couple the double quantum wells. → Hydrostatic pressure can couple the double quantum wells. → NOA can increase/decrease with hydrostatic pressure. → Overlap between wave functions depends on the magnetic field.

  11. Nonlinear optical rectification and optical absorption in GaAs-Ga{sub 1-x}Al{sub x}As asymmetric double quantum wells: Combined effects of applied electric and magnetic fields and hydrostatic pressure

    Energy Technology Data Exchange (ETDEWEB)

    Karabulut, I. [Department of Physics, Selcuk University, Konya 42075 (Turkey); Mora-Ramos, M.E. [Facultad de Ciencias, Universidad Autonoma del Estado de Morelos, Ave. Universidad 1001, CP 62209, Cuernavaca, Morelos (Mexico); Duque, C.A., E-mail: cduque_echeverri@yahoo.e [Instituto de Fisica, Universidad de Antioquia, AA 1226, Medellin (Colombia)

    2011-07-15

    The intersubband electron-related nonlinear optical absorption and nonlinear optical rectification in GaAs-Ga{sub 1-x}Al{sub x}As asymmetric double quantum wells are studied, under the influence of combined or independent applied electric and magnetic fields as well as hydrostatic pressure. The outcome of the density matrix formalism and the effective mass, and parabolic-band approximations have been considered as main theoretical tools for the description. It is obtained that under particular geometrical conditions, with or without electric and/or magnetic field strength, the optical rectification is null and, simultaneously, in such circumstances the optical absorption has a relative maximum. It is also detected that the influence of the hydrostatic pressure leads to increasing or decreasing behaviors of the nonlinear optical absorption in dependence of the particular regime of pressure values considered, with significant distinction of the cases of opposite electric field orientations. - Highlights: {yields} Maxima of the NOA correspond to zero in the NOR. {yields} Electric fields can couple the double quantum wells. {yields} Hydrostatic pressure can couple the double quantum wells. {yields} NOA can increase/decrease with hydrostatic pressure. {yields} Overlap between wave functions depends on the magnetic field.

  12. The Empirical Test of Multiple Asymmetric Effects of Monetary Policy in China%我国货币政策多重非对称效应实证检验

    Institute of Scientific and Technical Information of China (English)

    张细松

    2012-01-01

    The empirical test indicates that in different years China' s economy encounters positive or negative shock of money supply. China' s eastern regions, northeast regions, western areas and central areas are not always at the same time in the boom or recession phase of regional economic cycles. The empirical test indicates that the influence that is from monetary policy is of different control direction to the economy of four regions, which are in different regional economic cycles. In other words, there is multiple asymmetric effects of monetary policy in China.%实证检验表明:在不同的年份,我国经济或受到正向货币供给冲击,或受到负向货币供给冲击;我国东部地区、东北地区、西部地区和中部地区并不总是同时处于地区经济周期的繁荣或衰退阶段;我国不同调控方向的货币政策对处于地区经济周期不同阶段的四地区经济的影响是不相同的,即存在货币政策多重非对称效应。

  13. Effect of sonochemical synthesized TiO2 nanoparticles and coagulation bath temperature on morphology, thermal stability and pure water flux of asymmetric cellulose acetate membranes prepared via phase inversion method

    Directory of Open Access Journals (Sweden)

    Abedini Reza

    2012-01-01

    Full Text Available In this study, asymmetric pure CA and CA/ TiO2 composite membranes were prepared via phase inversion by dispersing TiO2 nanopaticles in the CA casting solutions induced by immersion precipitation in water coagulation bath. TiO2 nanoparticles, which were synthesized by the sonochemical method, were added into the casting solution with different concentrations. Effects of TiO2 nanoparticles concentration (0 wt. %, 5wt.%, 10wt.%, 15wt.%, 20wt.% and 25wt.% and coagulation bath temperature (CBT= 25°C, 50°C and 75°C on morphology, thermal stability and pure water flux (PWF of the prepared membranes were studied and discussed. Increasing TiO2 concentration in the casting solution film along with higher CBT resulted in increasing the membrane thickness, water content (WC, membrane porosity and pure water flux (PWF, also these changes facilitate macrovoids formation. Thermal gravimetric analysis (TGA shows that thermal stability of the composite membranes were improved by the addition of TiO2 nanopaticles. Also TGA results indicated that increasing CBT in each TiO2 concentration leads to the decreasing of decomposition temperature (Td of hybrid membranes.

  14. Shear deformation and grain refinement in pure Al by asymmetric rolling

    Institute of Scientific and Technical Information of China (English)

    ZUO Fang-qing; JIANG Jian-hua; SHAN Ai-dang; FANG Jian-min; ZHANG Xing-yao

    2008-01-01

    Asymmetric rolling(ASR), as one of severe plastic deformation(SPD) methods, was widely used to make ultra-fined materials with enhanced performance. Internal marks were used to show the shear deformation during asymmetric rolling with pure aluminium as a model material. Effects of reduction ratio and mismatch ratio on the shear deformation were studied. With the observed shear deformation results, equivalent strain was calculated. For lager shear deformation, rolling equipment was modified to increase friction between specimen and the rollers. Consequently, extremely fine grains with size of 500 nm are obtained in pure aluminium. With improved asymmetric rolling, the ability of grain refinement of ASR is greatly improved.

  15. Twin Higgs Asymmetric Dark Matter.

    Science.gov (United States)

    García García, Isabel; Lasenby, Robert; March-Russell, John

    2015-09-18

    We study asymmetric dark matter (ADM) in the context of the minimal (fraternal) twin Higgs solution to the little hierarchy problem, with a twin sector with gauged SU(3)^{'}×SU(2)^{'}, a twin Higgs doublet, and only third-generation twin fermions. Naturalness requires the QCD^{'} scale Λ_{QCD}^{'}≃0.5-20  GeV, and that t^{'} is heavy. We focus on the light b^{'} quark regime, m_{b^{'}}≲Λ_{QCD}^{'}, where QCD^{'} is characterized by a single scale Λ_{QCD}^{'} with no light pions. A twin baryon number asymmetry leads to a successful dark matter (DM) candidate: the spin-3/2 twin baryon, Δ^{'}∼b^{'}b^{'}b^{'}, with a dynamically determined mass (∼5Λ_{QCD}^{'}) in the preferred range for the DM-to-baryon ratio Ω_{DM}/Ω_{baryon}≃5. Gauging the U(1)^{'} group leads to twin atoms (Δ^{'}-τ^{'}[over ¯] bound states) that are successful ADM candidates in significant regions of parameter space, sometimes with observable changes to DM halo properties. Direct detection signatures satisfy current bounds, at times modified by dark form factors.

  16. Why Do Nucleosomes Unwrap Asymmetrically?

    Science.gov (United States)

    de Bruin, Lennart; Tompitak, Marco; Eslami-Mossallam, Behrouz; Schiessel, Helmut

    2016-07-01

    Nucleosomes, DNA spools with a protein core, engage about three-quarters of eukaryotic DNA and play a critical role in chromosomal processes, ranging from gene regulation, recombination, and replication to chromosome condensation. For more than a decade, micromanipulation experiments where nucleosomes are put under tension, as well as the theoretical interpretations of these experiments, have deepened our understanding of the stability and dynamics of nucleosomes. Here we give a theoretical explanation for a surprising new experimental finding: nucleosomes wrapped onto the 601 positioning sequence (the sequence used in most laboratories) respond highly asymmetrically to external forces by always unwrapping from the same end. Using a computational nucleosome model, we show that this asymmetry can be explained by differences in the DNA mechanics of two very short stretches on the wrapped DNA portion. Our finding suggests that the physical properties of nucleosomes, here the response to forces, can be tuned locally by the choice of the underlying base-pair sequence. This leads to a new view of nucleosomes: a physically highly varied set of DNA-protein complexes whose properties can be tuned on evolutionary time scales to their specific function in the genomic context. PMID:26991771

  17. Twin Higgs Asymmetric Dark Matter

    CERN Document Server

    García, Isabel García; March-Russell, John

    2015-01-01

    We study Asymmetric Dark Matter (ADM) in the context of the minimal (Fraternal) Twin Higgs solution to the little hierarchy problem, with a twin sector with gauged $SU(3)' \\times SU(2)'$, a twin Higgs, and only third generation twin fermions. Naturalness requires the QCD$^\\prime$ scale $\\Lambda'_{\\rm QCD} \\simeq 0.5 - 20 \\ {\\rm GeV}$, and $t'$ to be heavy. We focus on the light $b'$ quark regime, $m_{b'} \\lesssim \\Lambda'_{\\rm QCD}$, where QCD$^\\prime$ is characterised by a single scale $\\Lambda'_{\\rm QCD}$ with no light pions. A twin baryon number asymmetry leads to a successful DM candidate: the spin-3/2 twin baryon, $\\Delta' \\sim b'b'b'$, with a dynamically determined mass ($\\sim 5 \\Lambda'_{\\rm QCD}$) in the preferred range for the DM-to-baryon ratio $\\Omega_{\\rm DM}/\\Omega_{\\rm baryon} \\simeq 5$. Gauging the $U(1)'$ group leads to twin atoms ($\\Delta'$ - $\\bar {\\tau'}$ bound states) that are successful ADM candidates in significant regions of parameter space, sometimes with observable changes to DM halo ...

  18. Asymmetric total synthesis of vindoline.

    Science.gov (United States)

    Kato, Daisuke; Sasaki, Yoshikazu; Boger, Dale L

    2010-03-24

    A concise asymmetric total synthesis of (-)-vindoline (1) is detailed based on a tandem intramolecular [4+2]/[3+2] cycloaddition cascade of a 1,3,4-oxadiazole inspired by the natural product structure, in which the tether linking the initiating dienophile and oxadiazole bears a chiral substituent that controls the facial selectivity of the initiating Diels-Alder reaction and sets absolute stereochemistry of the remaining six stereocenters in the cascade cycloadduct. This key reaction introduces three rings and four C-C bonds central to the pentacyclic ring system setting all six stereocenters and introducing essentially all the functionality found in the natural product in a single step. Implementation of the approach also required the development of a unique ring expansion reaction to provide a six-membered ring suitably functionalized for introduction of the Delta (6, 7)-double bond found in the core structure of vindoline and defined our use of a protected hydroxymethyl group as the substituent used to control the stereochemical course of the cycloaddition cascade.

  19. Chaos suppression through asymmetric coupling

    Science.gov (United States)

    Bragard, J.; Vidal, G.; Mancini, H.; Mendoza, C.; Boccaletti, S.

    2007-12-01

    We study pairs of identical coupled chaotic oscillators. In particular, we have used Roessler (in the funnel and no funnel regimes), Lorenz, and four-dimensional chaotic Lotka-Volterra models. In all four of these cases, a pair of identical oscillators is asymmetrically coupled. The main result of the numerical simulations is that in all cases, specific values of coupling strength and asymmetry exist that render the two oscillators periodic and synchronized. The values of the coupling strength for which this phenomenon occurs is well below the previously known value for complete synchronization. We have found that this behavior exists for all the chaotic oscillators that we have used in the analysis. We postulate that this behavior is presumably generic to all chaotic oscillators. In order to complete the study, we have tested the robustness of this phenomenon of chaos suppression versus the addition of some Gaussian noise. We found that chaos suppression is robust for the addition of finite noise level. Finally, we propose some extension to this research.

  20. Twin Higgs Asymmetric Dark Matter.

    Science.gov (United States)

    García García, Isabel; Lasenby, Robert; March-Russell, John

    2015-09-18

    We study asymmetric dark matter (ADM) in the context of the minimal (fraternal) twin Higgs solution to the little hierarchy problem, with a twin sector with gauged SU(3)^{'}×SU(2)^{'}, a twin Higgs doublet, and only third-generation twin fermions. Naturalness requires the QCD^{'} scale Λ_{QCD}^{'}≃0.5-20  GeV, and that t^{'} is heavy. We focus on the light b^{'} quark regime, m_{b^{'}}≲Λ_{QCD}^{'}, where QCD^{'} is characterized by a single scale Λ_{QCD}^{'} with no light pions. A twin baryon number asymmetry leads to a successful dark matter (DM) candidate: the spin-3/2 twin baryon, Δ^{'}∼b^{'}b^{'}b^{'}, with a dynamically determined mass (∼5Λ_{QCD}^{'}) in the preferred range for the DM-to-baryon ratio Ω_{DM}/Ω_{baryon}≃5. Gauging the U(1)^{'} group leads to twin atoms (Δ^{'}-τ^{'}[over ¯] bound states) that are successful ADM candidates in significant regions of parameter space, sometimes with observable changes to DM halo properties. Direct detection signatures satisfy current bounds, at times modified by dark form factors. PMID:26430985

  1. Deaging and Asymmetric Energy Landscapes in Electrically Biased Ferroelectrics

    Energy Technology Data Exchange (ETDEWEB)

    Tutuncu, Goknur; Damjanovic, Dragan; Chen, Jun; Jones, Jacob L. (Ecole); (UST - China); (Florida)

    2015-09-01

    In ferroic materials, the dielectric, piezoelectric, magnetic, and elastic coefficients are significantly affected by the motion of domain walls. This motion can be described as the propagation of a wall across various types and strengths of pinning centers that collectively constitute a force profile or energetic landscape. Biased domain structures and asymmetric energy landscapes can be created through application of high fields (such as during electrical poling), and the material behavior in such states is often highly asymmetric. In some cases, this behavior can be considered as the electric analogue to the Bauschinger effect. The present Letter uses time-resolved, high-energy x-ray Bragg scattering to probe this asymmetry and the associated deaging effect in the ferroelectric morphotropic phase boundary composition 0.36BiScO{sub 3}-0.64PbTiO{sub 3}.

  2. Cosmology in time asymmetric extensions of general relativity

    CERN Document Server

    Leon, Genly

    2015-01-01

    We investigate the cosmological behavior in a universe governed by time asymmetric extensions of general relativity, which is a novel modified gravity based on the addition of new, time-asymmetric, terms on the Hamiltonian framework, in a way that the algebra of constraints and local physics remain unchanged. Nevertheless, at cosmological scales these new terms can have significant effects that can alter the universe evolution, both at early and late times, and the freedom in the choice of the involved modification function makes the scenario able to produce a huge class of cosmological behaviors. For basic ansatzes of modification, we perform a detailed dynamical analysis, extracting the stable late time solutions. Amongst others, we find that the universe can result in dark-energy dominated, accelerating solutions, even in the absence of an explicit cosmological constant, in which the dark energy can be quintessence-like, phantom-like, or behave as an effective cosmological constant. Moreover, it can result...

  3. Comparative study of symmetric and asymmetric somatic hybridization between common wheat and Haynaldia villosa

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Symmetric and asymmetric protoplast fusion between long term cell suspension-derived protoplasts of Triticum aestivum (cv. Jinan 177) and protoplasts of Haynaldia villosa prepared from one-year-old embryogeneric calli was performed by PEG method. In asymmetric fusion, donor calli were treated with gamma ray at a dose of 40, 60, 80 Gy (1.3 Gy/min) respectively and then used to isolate protoplasts. Results of morphological, cytological, biochemical (isozyme) and 5S rDNA spacer sequence analysis revealed that we obtained somatic hybrid lines at high frequency from both symmetric and asymmetric fusion. Hybrid plants were recovered from symmetric and low dose g-fusion combinations. GISH (genomic in situ hybridization) analysis proved exactly the existence of both parental chromosomes and the common occurrence of several kinds of translocation between them in the hybrid clones regenerated from symmetric and asymmetric fusion. And the elimination of donor DNA in hybrid clones regenerated from asymmetric fusion combinations was found to increase with the increasing gamma doses. It is concluded that transference and recombination of nuclear DNA can be achieved effectively by symmetric and asymmetric fusion, hybrids with small fragment translocation which are valuable in plant breeding can be obtained directly by asymmetric fusion.

  4. Asymmetric dense matter in holographic QCD

    Directory of Open Access Journals (Sweden)

    Shin Ik Jae

    2012-02-01

    Full Text Available We study asymmetric dense matter in holographic QCD.We construct asymmetric dense matter by considering two quark flavor branes with dierent quark masses in a D4/D6/D6 model. To calculate the symmetry energy in nuclear matter, we consider two quarks with equal masses and observe that the symmetry energy increases with the total charge showing the stiff dependence. This behavior is universal in the sense that the result is independent of parameters in the model. We also study strange (or hyperon matter with one light and one intermediate mass quarks. In addition to the vacuum properties of asymmetric matter, we calculate meson masses in asymmetric dense matter and discuss our results in the light of in-medium kaon masses.

  5. Massless sunset diagrams in finite asymmetric volumes

    CERN Document Server

    Niedermayer, Ferenc

    2016-01-01

    In this paper we present methods to compute massless sunset diagrams in finite asymmetric volumes in the framework of dimensional regularization and lattice regularization. We also consider 1-loop sums in both regularizations.

  6. Asymmetric cryptography based on wavefront sensing.

    Science.gov (United States)

    Peng, Xiang; Wei, Hengzheng; Zhang, Peng

    2006-12-15

    A system of asymmetric cryptography based on wavefront sensing (ACWS) is proposed for the first time to our knowledge. One of the most significant features of the asymmetric cryptography is that a trapdoor one-way function is required and constructed by analogy to wavefront sensing, in which the public key may be derived from optical parameters, such as the wavelength or the focal length, while the private key may be obtained from a kind of regular point array. The ciphertext is generated by the encoded wavefront and represented with an irregular array. In such an ACWS system, the encryption key is not identical to the decryption key, which is another important feature of an asymmetric cryptographic system. The processes of asymmetric encryption and decryption are formulized mathematically and demonstrated with a set of numerical experiments.

  7. Localization of Asymmetric Brain Function in Emotion and Depression

    OpenAIRE

    Herrington, John D.; Heller, Wendy; Mohanty, Aprajita; Engels, Anna S.; Banich, Marie T; Webb, Andrew G; Miller, Gregory A.

    2010-01-01

    Although numerous EEG studies have shown that depression is associated with abnormal functional asymmetries in frontal cortex, fMRI and PET studies have largely failed to identify specific brain areas showing this effect. The present study tested the hypothesis that emotion processes are related to asymmetric patterns of fMRI activity, particularly within dorsolateral prefrontal cortex (DLPFC). Eleven depressed and 18 control participants identified the color in which pleasant, neutral, and u...

  8. Enhanced Second Harmonic Generation from Coupled Asymmetric Plasmonic Metal Nanostructures

    OpenAIRE

    Yildiz, Bilge Can; Tasgin, Mehmet Emre; Abak, Musa Kurtulus; Coskun, Sahin; Unalan, Husnu Emrah; Bek, Alpan

    2014-01-01

    We show that second harmonic generation can be enhanced by Fano resonant coupling of asymmetric plasmonic metal nanostructures. We develop a theoretical model examining the effects of electromagnetic interaction between two metal nanostructures on the second harmonic generation. We compare the second harmonic generation efficiency of a single plasmonic metal nanostructure with that of two coupled ones. We show that second harmonic generation from a single metal nanostructure can be enhanced a...

  9. Reflection-asymmetric nuclear deformations within the Density Functional Theory

    CERN Document Server

    Olsen, E; Nazarewicz, W; Stoitsov, M; 10.1088/1742-6596/402/1/012034

    2013-01-01

    Within the nuclear density functional theory (DFT) we study the effect of reflection-asymmetric shapes on ground-state binding energies and binding energy differences. To this end, we developed the new DFT solver AxialHFB that uses an approximate second-order gradient to solve the Hartree-Fock-Bogoliubov equations of superconducting DFT with the quasi-local Skyrme energy density functionals. Illustrative calculations are carried out for even-even isotopes of radium and thorium.

  10. Asymmetric Superradiant Scattering Patterns from Bose–Einstein Condensates

    International Nuclear Information System (INIS)

    The asymmetric patterns of superradiance from Bose–Einstein condensates are studied for the spatially inhomogeneous pump pulse with the semiclassical Maxwell-Schrödinger equations. The coupling dynamics between the optical field and condensate in the strong pulse and a faded wing in the weak coupling regime are discussed, which not only explain the spatial effects in the process of superradiance, but also supply a new method to control its patterns

  11. Fermion self-energy in magnetized chirally asymmetric QED matter

    CERN Document Server

    Rybalka, D O

    2016-01-01

    The fermion self-energy is calculated for a cold QED plasma with chiral chemical potential in a magnetic field. It is found that a momentum shift parameter dynamically generated in such a plasma leads to a modification of the chiral magnetic effect current. It is argued that the momentum shift parameter can be relevant for the evolution of magnetic field in the chirally asymmetric primordial plasma in the early Universe.

  12. Asymmetric light reflectance from metal nanoparticle arrays on dielectric surfaces

    OpenAIRE

    Huang, K.; Pan, W.; Zhu, J. F.; Li, J.C.; Gao, N; Liu, C; Ji, L.; Yu, E. T.; Kang, J Y

    2015-01-01

    Asymmetric light reflectance associated with localized surface plasmons excited in metal nanoparticles on a quartz substrate is observed and analyzed. This phenomenon is explained by the superposition of two waves, the wave reflected by the air/quartz interface and that reflected by the metal nanoparticles, and the resulting interference effects. Far field behavior investigation suggests that zero reflection can be achieved by optimizing the density of metal nanoparticles. Near field behavior...

  13. Origin of asymmetric reversal modes in ferromagnetic/antiferromagnetic multilayers

    OpenAIRE

    Beckmann, B.; Nowak, U.; Usadel, K. D.

    2004-01-01

    Experimentally an asymmetry of the reversal modes has been found in certain exchange bias systems. From a numerical investigation of the domain state model evidence is gained that this effect depends on the angle between the easy axis of the antiferromagnet and the applied magnetic field. Depending on this angle the ferromagnet reverses either symmetrically, e. g. by a coherent rotation on both sides of the loop, or the reversal is asymmetric with a non uniform reversal mode for the ascending...

  14. Worst Asymmetrical Short-Circuit Current

    DEFF Research Database (Denmark)

    Arana Aristi, Iván; Holmstrøm, O; Grastrup, L;

    2010-01-01

    In a typical power plant, the production scenario and the short-circuit time were found for the worst asymmetrical short-circuit current. Then, a sensitivity analysis on the missing generator values was realized in order to minimize the uncertainty of the results. Afterward the worst asymmetrical...... short-circuit current was analyzed in order to compare the results with the allowable DC current component based in the IEC. Finally the normal operating condition for the power plant was modeled....

  15. An asymmetric pericyclic cascade approach to oxindoles

    OpenAIRE

    Richmond, Edward

    2014-01-01

    The research in this thesis describes an asymmetric pericyclic cascade approach to the synthesis of a range of enantioenriched oxindoles using enantiopure oxazolidine derived nitrones and disubstituted ketenes. Chapter 1 aims to place this work in the context of the literature, describing other commonly employed or state-of-the-art asymmetric approaches to oxindoles and related compounds. Examples of where these approaches have been used successfully in the total synthesis of related indol...

  16. Asymmetric Membrane Osmotic Capsules for Terbutaline Sulphate

    OpenAIRE

    Gobade, N. G.; Marina Koland; K H Harish

    2012-01-01

    The aim of the present study was to design an asymmetric membrane capsule, an osmotic pump-based drug delivery system of ethyl cellulose for controlled release of terbutaline sulphate. asymmetric membrane capsules contains pore-forming water soluble additive, sorbitol in different concentrations in the capsule shell membrane, which after coming in contact with water, dissolves, resulting in an in situ formation of a microporous structure. The terbutaline sulphate is a β-adrenoreceptor agonist...

  17. Novel strategies for asymmetric hydrogenation reactions

    OpenAIRE

    Chen, Dianjun

    2011-01-01

    This thesis describes two novel possibilities for asymmetric hydrogenation: enantioselective hydrogenation using chiral ionic liquid systems and metal-free hydrogenation with boranes. In the first part, asymmetric hydrogenation systems using chiral ionic liquids in combination with racemic rhodium catalyst are presented. Enantioselectivities up to 69% ee were achieved in homogeneous Rh-catalyzed hydrogenation with tropos ligand (BIPHEP, sulfonated BIPHEP) in a proline derived cation chiral io...

  18. Asymmetric septal hypertrophy and hypothyroidism in children.

    OpenAIRE

    Altman, D I; Murray, J.; Milner, S.; Dansky, R; Levin, S. E.

    1985-01-01

    Any echocardiographic study of two children with hypothyroidism demonstrated the presence of asymmetric septal hypertrophy. One child died aged 11 months, and pronounced thickening of the interventricular septum was confirmed at necropsy. There was also hypertrophy of the left ventricular free wall. Histological examination showed only slight muscle fibre disarray, but there was striking vacuolation and hypertrophy of muscle fibres. In the second case, a child aged five years, the asymmetric ...

  19. Effects of rotation and magnetic field on the nonlinear peristaltic flow of a second-order fluid in an asymmetric channel through a porous medium

    Institute of Scientific and Technical Information of China (English)

    A.M.Abd-Alla; S.M.Abo-Dahab; H.D.El-Shahrany

    2013-01-01

    In this paper,the effects of both rotation and magnetic field of the peristaltic transport of a second-order fluid through a porous medium in a channel are studied analytically and computed numerically.The material is represented by the constitutive equations for a second-order fluid.Closed-form solutions under the consideration of long wavelength and low Reynolds number is presented.The analytical expressions for the pressure gradient,pressure rise,friction force,stream function,shear stress,and velocity are obtained in the physical domain.The effects of the non-dimensional wave amplitude,porosity,magnetic field,rotation,and the dimensionless time-mean flow in the wave frame are analyzed theoretically and computed numerically.Numerical results are given and illustrated graphically in each case considered.Comparison was made with the results obtained in the presence and absence of rotation,magnetic field,and porosity.The results indicate that the effects of the non-dimensional wave amplitude,porosity,magnetic field,rotation,and the dimensionless time-mean flow are very pronounced in the phenomena.

  20. A Numerical Comparison of Symmetric and Asymmetric Supersonic Wind Tunnels

    Science.gov (United States)

    Clark, Kylen D.

    Supersonic wind tunnels are a vital aspect to the aerospace industry. Both the design and testing processes of different aerospace components often include and depend upon utilization of supersonic test facilities. Engine inlets, wing shapes, and body aerodynamics, to name a few, are aspects of aircraft that are frequently subjected to supersonic conditions in use, and thus often require supersonic wind tunnel testing. There is a need for reliable and repeatable supersonic test facilities in order to help create these vital components. The option of building and using asymmetric supersonic converging-diverging nozzles may be appealing due in part to lower construction costs. There is a need, however, to investigate the differences, if any, in the flow characteristics and performance of asymmetric type supersonic wind tunnels in comparison to symmetric due to the fact that asymmetric configurations of CD nozzle are not as common. A computational fluid dynamics (CFD) study has been conducted on an existing University of Michigan (UM) asymmetric supersonic wind tunnel geometry in order to study the effects of asymmetry on supersonic wind tunnel performance. Simulations were made on both the existing asymmetrical tunnel geometry and two axisymmetric reflections (of differing aspect ratio) of that original tunnel geometry. The Reynolds Averaged Navier Stokes equations are solved via NASAs OVERFLOW code to model flow through these configurations. In this way, information has been gleaned on the effects of asymmetry on supersonic wind tunnel performance. Shock boundary layer interactions are paid particular attention since the test section integrity is greatly dependent upon these interactions. Boundary layer and overall flow characteristics are studied. The RANS study presented in this document shows that the UM asymmetric wind tunnel/nozzle configuration is not as well suited to producing uniform test section flow as that of a symmetric configuration, specifically one

  1. ASYMMETRICALLY SECURED EGMP OVER MANET’S

    Directory of Open Access Journals (Sweden)

    Sayed Mohammed Raja

    2013-06-01

    Full Text Available Group communications are significant in Mobile Ad hoc Networks (MANET. Multicast is an wellorganized technique for applying group communications. Yet, it is interesting to implement effective andaccessible multicast in MANET due to the effort in group member management and multicasting of packets forwarding in an active topology. We suggest a Asymmetrically Secured novel Efficient Geographic Multicast Protocol (EGMP. EGMP uses a practical-zone-based arrangement to implement accessible and effective groupmember management. A network-wide zone-based bi-directional tree is made to attain more well-organized member management and multicast delivery. The location information is used to monitor the zone structure, multicast tree building and multicast packets forwarding, which capably reduce the overhead for route finding and tree structure maintenance. Some approaches have been suggested to further improvement in the efficiency of the protocol, for example, presenting the concept of zone depth for construction an ideal tree structure and adding the position search of group of members with the ordered group member management. To switch empty zone problem met by most routing protocols using a zone structure. Finally, we plan a pattern to switch the security problem faced by the multicasting. The scalability and the productivity of EGMP are assessed through simulations and quantitative analysis. Our results prove that EGMP has great packet delivery ratio, and low control overhead, and is accessible to both group size and network size. EGMP has expressively lower control overhead, data transmission overhead, and multicast group joining delay.

  2. Asymmetric translation between multiple representations in chemistry

    Science.gov (United States)

    Lin, Yulan I.; Son, Ji Y.; Rudd, James A., II

    2016-03-01

    Experts are more proficient in manipulating and translating between multiple representations (MRs) of a given concept than novices. Studies have shown that instruction using MR can increase student understanding of MR, and one model for MR instruction in chemistry is the chemistry triplet proposed by Johnstone. Concreteness fading theory suggests that presenting concrete representations before abstract representations can increase the effectiveness of MR instruction; however, little work has been conducted on varying the order of different representations during instruction and the role of concreteness in assessment. In this study, we investigated the application of concreteness fading to MR instruction and assessment in teaching chemistry. In two experiments, undergraduate students in either introductory psychology courses or general chemistry courses were given MR instruction on phase changes using different orders of presentation and MR assessment questions based on the representations in the chemistry triplet. Our findings indicate that the order of presentation based on levels of concreteness in MR chemistry instruction is less important than implementation of comprehensive MR assessments. Even after MR instruction, students display an asymmetric understanding of the chemical phenomenon on the MR assessments. Greater emphasis on MR assessments may be an important component in MR instruction that effectively moves novices toward more expert MR understanding.

  3. Study on asymmetric effect of Chinese stock markets%中国股票市场的非对称效应研究

    Institute of Scientific and Technical Information of China (English)

    刘庆富; 周程远

    2012-01-01

    为检测重大风险事件对我国股票市场影响的非对称效应,运用贝叶斯MCMC推断技术对我国上证综指和深证成指进行了实证研究.研究结果显示:基于t-分布的门限随机波动模型比基于正态分布的随机波动模型能更加合理地刻画经济事件、政治事件和自然灾难对我国股票市场收益和波动影响的非对称特性.并且发现,经济事件、政治事件和自然灾难对我国股票市场收益和波动的影响均具有显著的非对称性.相对而言,政治事件对股票市场收益的影响存在正向杠杆效应,而经济事件和自然灾难却存在反向杠杆效应;经济事件和政治事件对股票市场波动的冲击存在正向杠杆效应,而自然灾难则存在反向杠杆效应.此外,除在牛市环境下利好经济事件和利空经济事件对股票市场收益和波动的影响具有反向杠杆效应之外,其它风险事件在熊市和牛市环境下对收益和波动的影响均具有正向杠杆效应.%For investigating the asymmetry of impact of major risk events on ChTo investigate the asymmetry of the impacts of major risk events on Chinese stock market, this paper studies the SSE composite index and SZSE component index using the threshold stochastic volatility (THSV) model with student distribution approach developed based on Bayesian MCMC technique. The empirical results show that the THSV model with student distribution are more comprehensive than with normal distribution for describing the asymmetry of the impacts of economic events, political events and natural disasters on the returns and volatilities in Chinese stock market. There are prominent asymmetries of impact of economic events, politic events and natural disasters on the returns and volatilities. Correspondingly, there are positive leverage effects in political events and reversed leverage effects in both economic and natural disaster events on returns. And there are positive leverage

  4. Asymmetric dynamics and critical behavior in the Bak-Sneppen model

    OpenAIRE

    Garcia, Guilherme J. M.; Dickman, Ronald

    2004-01-01

    We investigate, using mean-field theory and simulation, the effect of asymmetry on the critical behavior and probability density of Bak-Sneppen models. Two kinds of anisotropy are investigated: (i) different numbers of sites to the left and right of the central (minimum) site are updated and (ii) sites to the left and right of the central site are renewed in different ways. Of particular interest is the crossover from symmetric to asymmetric scaling for weakly asymmetric dynamics, and the col...

  5. High performance of junctionless MOSFET with asymmetric gate

    Science.gov (United States)

    Wang, Ying; Tang, Yan; Sun, Ling-ling; Cao, Fei

    2016-09-01

    In this work, we propose a junctionless MOSFET with asymmetric gates (AG-JL MOSFET). This device is a double gate structure with a lateral offset between the gate, and this leads to different characteristic than a conventional double gate structure. Specifically, the asymmetric gate modulates the effective channel length depending on whether the device is in the ON or OFF state, which this leads to more ideal device characteristics. A comprehensive device performance comparison including the ION/IOFF ratio, subthreshold slope (SS), and drain-induced barrier lowering (DIBL) between the proposed device and a conventional device is presented. The proposed device exhibits superior performance when compared a conventional device, and results show that it is also less sensitive to process variations.

  6. Asymmetric excitation of surface plasmons by dark mode coupling

    KAUST Repository

    Zhang, X.

    2016-02-19

    Control over surface plasmons (SPs) is essential in a variety of cutting-edge applications, such as highly integrated photonic signal processing systems, deep-subwavelength lasing, high-resolution imaging, and ultrasensitive biomedical detection. Recently, asymmetric excitation of SPs has attracted enormous interest. In free space, the analog of electromagnetically induced transparency (EIT) in metamaterials has been widely investigated to uniquely manipulate the electromagnetic waves. In the near field, we show that the dark mode coupling mechanism of the classical EIT effect enables an exotic and straightforward excitation of SPs in a metasurface system. This leads to not only resonant excitation of asymmetric SPs but also controllable exotic SP focusing by the use of the Huygens-Fresnel principle. Our experimental findings manifest the potential of developing plasmonic metadevices with unique functionalities.

  7. Broadband terahertz metamaterial absorber based on sectional asymmetric structures

    Science.gov (United States)

    Gong, Cheng; Zhan, Mingzhou; Yang, Jing; Wang, Zhigang; Liu, Haitao; Zhao, Yuejin; Liu, Weiwei

    2016-01-01

    We suggest and demonstrate the concept and design of sectional asymmetric structures which can manipulate the metamaterial absorber’s working bandwidth with maintaining the other inherent advantages. As an example, a broadband terahertz perfect absorber is designed to confirm its effectiveness. The absorber’s each cell integrates four sectional asymmetric rings, and the entire structure composed of Au and Si3N4 is only 1.9 μm thick. The simulation results show the bandwidth with absorptivity being larger than 90% is extended by about 2.8 times comparing with the conventional square ring absorber. The composable small cell, ultra-thin, and broadband absorption with polarization and incident angle insensitivity will make the absorber suitable for the applications of focal plane array terahertz imaging. PMID:27571941

  8. Localization of Asymmetric Brain Function in Emotion and Depression

    Science.gov (United States)

    Herrington, John D.; Heller, Wendy; Mohanty, Aprajita; Engels, Anna S.; Banich, Marie T.; Webb, Andrew G.; Miller, Gregory A.

    2011-01-01

    Although numerous EEG studies have shown that depression is associated with abnormal functional asymmetries in frontal cortex, fMRI and PET studies have largely failed to identify specific brain areas showing this effect. The present study tested the hypothesis that emotion processes are related to asymmetric patterns of fMRI activity, particularly within dorsolateral prefrontal cortex (DLPFC). Eleven depressed and 18 control participants identified the color in which pleasant, neutral, and unpleasant words were printed. Both groups showed a leftward lateralization for pleasant words in DLPFC. In a neighboring DLPFC area, the depression group showed more right-lateralized activation than controls, replicating EEG findings. These data confirm that emotional stimulus processing and trait depression are associated with asymmetric brain functions in distinct subregions of the DLPFC that may go undetected unless appropriate analytic procedures are used. PMID:20070577

  9. Chiral cyclopentadienylruthenium sulfoxide catalysts for asymmetric redox bicycloisomerization

    Science.gov (United States)

    Ryan, Michael C; Rao, Meera

    2016-01-01

    Summary A full account of our efforts toward an asymmetric redox bicycloisomerization reaction is presented in this article. Cyclopentadienylruthenium (CpRu) complexes containing tethered chiral sulfoxides were synthesized via an oxidative [3 + 2] cycloaddition reaction between an alkyne and an allylruthenium complex. Sulfoxide complex 1 containing a p-anisole moiety on its sulfoxide proved to be the most efficient and selective catalyst for the asymmetric redox bicycloisomerization of 1,6- and 1,7-enynes. This complex was used to synthesize a broad array of [3.1.0] and [4.1.0] bicycles. Sulfonamide- and phosphoramidate-containing products could be deprotected under reducing conditions. Catalysis performed with enantiomerically enriched propargyl alcohols revealed a matched/mismatched effect that was strongly dependent on the nature of the solvent. PMID:27559366

  10. Asymmetric excitation of surface plasmons by dark mode coupling.

    Science.gov (United States)

    Zhang, Xueqian; Xu, Quan; Li, Quan; Xu, Yuehong; Gu, Jianqiang; Tian, Zhen; Ouyang, Chunmei; Liu, Yongmin; Zhang, Shuang; Zhang, Xixiang; Han, Jiaguang; Zhang, Weili

    2016-02-01

    Control over surface plasmons (SPs) is essential in a variety of cutting-edge applications, such as highly integrated photonic signal processing systems, deep-subwavelength lasing, high-resolution imaging, and ultrasensitive biomedical detection. Recently, asymmetric excitation of SPs has attracted enormous interest. In free space, the analog of electromagnetically induced transparency (EIT) in metamaterials has been widely investigated to uniquely manipulate the electromagnetic waves. In the near field, we show that the dark mode coupling mechanism of the classical EIT effect enables an exotic and straightforward excitation of SPs in a metasurface system. This leads to not only resonant excitation of asymmetric SPs but also controllable exotic SP focusing by the use of the Huygens-Fresnel principle. Our experimental findings manifest the potential of developing plasmonic metadevices with unique functionalities. PMID:26989777

  11. Examining Asymmetrical Relationships of Organizational Learning Antecedents: A Theoretical Model

    Directory of Open Access Journals (Sweden)

    Ery Tri Djatmika

    2016-02-01

    Full Text Available Global era is characterized by highly competitive advantage market demand. Responding to the challenge of rapid environmental changes, organizational learning is becoming a strategic way and solution to empower people themselves within the organization in order to create a novelty as valuable positioning source. For research purposes, determining the influential antecedents that affect organizational learning is vital to understand research-based solutions given for practical implications. Accordingly, identification of variables examined by asymmetrical relationships is critical to establish. Possible antecedent variables come from organizational and personal point of views. It is also possible to include a moderating one. A proposed theoretical model of asymmetrical effects of organizational learning and its antecedents is discussed in this article.

  12. Influence of swimming strategy on microorganism separation by asymmetric obstacles

    CERN Document Server

    Berdakin, I; Moshchalkov, V V; Venken, L; Dierckx, S; Vanderleyden, S J; Silhanek, A V; Condat, C A; Marconi, V I

    2013-01-01

    It has been shown that a nanoliter chamber separated by a wall of asymmetric obstacles can lead to an inhomogeneous distribution of self-propelled microorganisms. Although it is well established that this rectification effect arises from the interaction between the swimmers and the non-centrosymmetric pillars, here we demonstrate numerically that its efficiency is strongly dependent on the detailed dynamics of the individual microorganism. In particular, for the case of run-and-tumble dynamics, the distribution of run lengths, the rotational diffusion and the partial preservation of run orientation memory through a tumble are important factors when computing the rectification efficiency. In addition, we optimize the geometrical dimensions of the asymmetric pillars in order to maximize the swimmer concentration and we illustrate how it can be used for sorting by swimming strategy in a long array of parallel obstacles.

  13. Influence of swimming strategy on microorganism separation by asymmetric obstacles

    Science.gov (United States)

    Berdakin, I.; Jeyaram, Y.; Moshchalkov, V. V.; Venken, L.; Dierckx, S.; Vanderleyden, S. J.; Silhanek, A. V.; Condat, C. A.; Marconi, V. I.

    2013-05-01

    It has been shown that a nanoliter chamber separated by a wall of asymmetric obstacles can lead to an inhomogeneous distribution of self-propelled microorganisms. Although it is well established that this rectification effect arises from the interaction between the swimmers and the noncentrosymmetric pillars, here we demonstrate numerically that its efficiency is strongly dependent on the detailed dynamics of the individual microorganism. In particular, for the case of run-and-tumble dynamics, the distribution of run lengths, the rotational diffusion, and the partial preservation of run orientation memory through a tumble are important factors when computing the rectification efficiency. In addition, we optimize the geometrical dimensions of the asymmetric pillars in order to maximize the swimmer concentration and we illustrate how it can be used for sorting by swimming strategy in a long array of parallel obstacles.

  14. NONLINEAR EXTENSION OF ASYMMETRIC GARCH MODEL WITHIN NEURAL NETWORK FRAMEWORK

    Directory of Open Access Journals (Sweden)

    Josip Arnerić

    2016-05-01

    Full Text Available The importance of volatility for all market participants has led to the development and application of various econometric models. The most popular models in modelling volatility are GARCH type models because they can account excess kurtosis and asymmetric effects of financial time series. Since standard GARCH(1,1 model usually indicate high persistence in the conditional variance, the empirical researches turned to GJR-GARCH model and reveal its superiority in fitting the asymmetric heteroscedasticity in the data. In order to capture both asymmetry and nonlinearity in data, the goal of this paper is to develop a parsimonious NN model as an extension to GJR-GARCH model and to determine if GJR-GARCH-NN outperforms the GJR-GARCH model.

  15. 我国货币政策的区域非对称效应研究%Research on the Regional Asymmetric Effect under Monetary Policy Shock in China

    Institute of Scientific and Technical Information of China (English)

    李鹏飞; 黄丽君

    2016-01-01

    Monetary policy as a means of national macro -economy control has been the central bank's attention.For a long time,however,the focus of academic research has always been on the overall operation of the national economy,ignoring the differences within the regions,thus,resulting in the regional asymmetric effect under the unitary monetary policy.In this paper, we take the quantitative analysis using the VAR model to compare different responses in the face of monetary authority's unitary monetary policy shocks between the eastern,central and western regions of China based on the annual statistical data from the 1978 to 2013.It is found that the output response peak and the cumulative response peak of the economically developed eastern region exceed those of the Middle and West regions,while in terms of price response peak and cumulative response peak,the central region exceedsthe other two .Thus the conclusion can be reached that there is regional asymmetric effect under monetary policy shock in China.Finally,in response to the problem some policy recommendations are put forward.%货币政策作为国家宏观经济调控的手段一直受到央行的高度重视,一直以来,学术研究重点在于把握国民经济的整体运行情况,而忽略了区域内部特殊性,产生了统一货币政策下的区域非对称效应。本文采用了1978年~2013年的年度统计数据,基于向量自回归模型(VAR)定量分析比较我国东部、中部、西部地区在面对货币当局统一货币政策冲击时的不同响应,得出经济发达的东部区域产出响应峰值和累积响应峰值均超出中西部区域,而价格反应强度中部地区响应峰值和累积脉冲响应峰值最大,强于东部和西部地区,由此证明了我国存在货币政策区域效应非对称性,并针对其产生的原因提出相关的政策建议。

  16. ADMonium: Asymmetric Dark Matter Bound State

    CERN Document Server

    Bi, Xiao-Jun; Ko, P; Li, Jinmian; Li, Tianjun

    2016-01-01

    We propose a novel framework for asymmetric scalar dark matter (ADM), which has interesting collider phenomenology in terms of an unstable ADM bound state (ADMonium) produced via Higgs portals. ADMonium is a natural consequence of the basic features of ADM: the (complex scalar) ADM is charged under a dark local $U(1)_d$ symmetry which is broken at a low scale and provides a light gauge boson $X$. The dark gauge coupling is strong and then ADM can annihilate away into $X$-pair effectively. Therefore, the ADM can form bound state due to its large self-interaction via $X$ mediation. To explore the collider signature of ADMonium, we propose that ADM has a two-Higgs doublet portal. The ADMonium can have a sizable mixing with the heavier Higgs boson, which admits a large cross section of ADMonium production associated with $b\\bar b$. Of particular interest, our setup nicely explains the recent di-photon anomaly at 750 GeV via the events from ${\\rm ADMonium}\\ra 2X(\\ra e^+e^-)$, where the electrons are identified as ...

  17. Asymmetric vector mesons produced in nuclear collisions

    CERN Document Server

    Dremin, I M

    2016-01-01

    It is argued that the experimentally observed phenomenon of asymmetric shapes of vector mesons produced in nuclear media during high energy nucleus-nucleus collisions can be explained as Fano-Feshbach resonances. It has been observed that the mass distributions of lepton pairs created at meson decays decline from the traditional Breit-Wigner shape with some excess in the low-mass wing of the resonance. It is clear that the whole phenomenon is related to some interaction with the nuclear medium. Moreover, it can be further detalized in quantum mechanics as the interference of direct and continuum states in Fano-Feshbach effect. To reveal the nature of the interaction it is proposed to use a phenomenological model of the additional contribution due to Cherenkov gluons. They can be created because of the excess of the refractivity index over 1 just in the low-mass wing as required by the classical Cherenkov treatment. In quantum mechanics, this requirement is related to the positive real part of the interaction ...

  18. 不对称导线对输电转角塔动力性能影响研究%Effects of Asymmetric Cables on the Dynamic Characteristics of Transmission Angle-tower

    Institute of Scientific and Technical Information of China (English)

    李鹏云; 陈波; 张峰; 王干军; 宋春芳

    2012-01-01

    研究了不对称导线对输电转角塔动力特性的影响.首先基于空间杆系有限元理论建立了输电转角塔的力学模型.然后基于空间索单元建立了输电导线的力学模型.在此基础上组集形成输电塔线耦连体系分析模型.以中国某大跨度输电转角塔为实际工程背景,基于有限元方法考察了该结构的塔线耦连振动效应.进一步进行导线影响的参数研究,考察了相邻导线对输电塔本身振动特性的影响.结果表明,输电转角塔的塔线耦连效应显著,结构的扭转振型受到导线的影响非常显著.因此在转角塔的设计建造过程中,应当充分考虑到导线参数的影响.%The effects of asymmetric cables on the dynamic characteristics of transmission angle-tower are actively investigated in this study. The mechanical model of the transmission angle-tower and cables are developed based on the spatial member finite element approach. The coupling vibration model of the transmission tower-line system is constructed for further analysis. A real long span transmission angle tower system is taken as an example to examine the properties of the dynamic coupling effects based on finite element method. The parametric study is carried out to examine the effects of the cable on the dynamic properties of the angle tower. The made observations indicate that the dynamic coupling effects of the tower and cables are obvious and the rotational modes of the tower are substantially affected by the cables. The influence of the cables on the transmission angle tower should be taken into consideration in the structural design and construction.

  19. Asymmetric statistical features of the Chinese domestic and international gold price fluctuation

    Science.gov (United States)

    Cao, Guangxi; Zhao, Yingchao; Han, Yan

    2015-05-01

    Analyzing the statistical features of fluctuation is remarkably significant for financial risk identification and measurement. In this study, the asymmetric detrended fluctuation analysis (A-DFA) method was applied to evaluate asymmetric multifractal scaling behaviors in the Shanghai and New York gold markets. Our findings showed that the multifractal features of the Chinese and international gold spot markets were asymmetric. The gold return series persisted longer in an increasing trend than in a decreasing trend. Moreover, the asymmetric degree of multifractals in the Chinese and international gold markets decreased with the increase in fluctuation range. In addition, the empirical analysis using sliding window technology indicated that multifractal asymmetry in the Chinese and international gold markets was characterized by its time-varying feature. However, the Shanghai and international gold markets basically shared a similar asymmetric degree evolution pattern. The American subprime mortgage crisis (2008) and the European debt crisis (2010) enhanced the asymmetric degree of the multifractal features of the Chinese and international gold markets. Furthermore, we also make statistical tests for the results of multifractatity and asymmetry, and discuss the origin of them. Finally, results of the empirical analysis using the threshold autoregressive conditional heteroskedasticity (TARCH) and exponential generalized autoregressive conditional heteroskedasticity (EGARCH) models exhibited that good news had a more significant effect on the cyclical fluctuation of the gold market than bad news. Moreover, good news exerted a more significant effect on the Chinese gold market than on the international gold market.

  20. Computational analysis of asymmetric water entry of wedge and ship section at constant velocity

    Science.gov (United States)

    Rahaman, Md. Mashiur; Ullah, Al Habib; Afroz, Laboni; Shabnam, Sharmin; Sarkar, M. A. Rashid

    2016-07-01

    Water impact problems receive much attention due to their short duration and large unsteady component of hydrodynamic loads. The effect of water entry has several important applications in various aspects of the naval field. Significant attention has been given to various water entry phenomena such as ship slamming, planning hulls, high-speed hydrodynamics of seaplanes, surface-piercing propellers and the interaction of high-speed liquid drops with structural elements. Asymmetric water entry may be caused by various natural phenomena such as weather conditions or strong winds. Since the determination of hydrodynamic impact load plays a vital role in designing safe and effcient vessels, an accurate and reliable prediction method is necessary to investigate asymmetric water entry problems. In this paper, water entry of a two-dimensional wedge and ship section at constant velocity in asymmetric condition will be analysed numerically and the effects of asymmetric impact on the velocity and pressure distribution will be discussed. The finite volume method is employed to solve the dynamic motion of the wedge in two-phase flow. During the water entry, the air and water interface is described implicitly by the volume of fluid (VOF) scheme. The numerical code and method was first validated for symmetric condition by one of the present author is applied for asymmetric wedge and ship section. The free surface, velocity and pressure distribution for asymmetric water entry are investigated and visualized with contour plots at different time steps.

  1. Exposing asymmetric gray matter vulnerability in amyotrophic lateral sclerosis

    Directory of Open Access Journals (Sweden)

    Matthew S. Devine

    2015-01-01

    Full Text Available Limb weakness in amyotrophic lateral sclerosis (ALS is typically asymmetric. Previous studies have identified an effect of limb dominance on onset and spread of weakness, however relative atrophy of dominant and non-dominant brain regions has not been investigated. Our objective was to use voxel-based morphometry (VBM to explore gray matter (GM asymmetry in ALS, in the context of limb dominance. 30 ALS subjects were matched with 17 healthy controls. All subjects were right-handed. Each underwent a structural MRI sequence, from which GM segmentations were generated. Patterns of GM atrophy were assessed in ALS subjects with first weakness in a right-sided limb (n = 15 or left-sided limb (n = 15. Within each group, a voxelwise comparison was also performed between native and mirror GM images, to identify regions of hemispheric GM asymmetry. Subjects with ALS showed disproportionate atrophy of the dominant (left motor cortex hand area, irrespective of the side of first limb weakness (p < 0.01. Asymmetric atrophy of the left somatosensory cortex and temporal gyri was only observed in ALS subjects with right-sided onset of limb weakness. Our VBM protocol, contrasting native and mirror images, was able to more sensitively detect asymmetric GM pathology in a small cohort, compared with standard methods. These findings indicate particular vulnerability of dominant upper limb representation in ALS, supporting previous clinical studies, and with implications for cortical organisation and selective vulnerability.

  2. Exposing asymmetric gray matter vulnerability in amyotrophic lateral sclerosis.

    Science.gov (United States)

    Devine, Matthew S; Pannek, Kerstin; Coulthard, Alan; McCombe, Pamela A; Rose, Stephen E; Henderson, Robert D

    2015-01-01

    Limb weakness in amyotrophic lateral sclerosis (ALS) is typically asymmetric. Previous studies have identified an effect of limb dominance on onset and spread of weakness, however relative atrophy of dominant and non-dominant brain regions has not been investigated. Our objective was to use voxel-based morphometry (VBM) to explore gray matter (GM) asymmetry in ALS, in the context of limb dominance. 30 ALS subjects were matched with 17 healthy controls. All subjects were right-handed. Each underwent a structural MRI sequence, from which GM segmentations were generated. Patterns of GM atrophy were assessed in ALS subjects with first weakness in a right-sided limb (n = 15) or left-sided limb (n = 15). Within each group, a voxelwise comparison was also performed between native and mirror GM images, to identify regions of hemispheric GM asymmetry. Subjects with ALS showed disproportionate atrophy of the dominant (left) motor cortex hand area, irrespective of the side of first limb weakness (p < 0.01). Asymmetric atrophy of the left somatosensory cortex and temporal gyri was only observed in ALS subjects with right-sided onset of limb weakness. Our VBM protocol, contrasting native and mirror images, was able to more sensitively detect asymmetric GM pathology in a small cohort, compared with standard methods. These findings indicate particular vulnerability of dominant upper limb representation in ALS, supporting previous clinical studies, and with implications for cortical organisation and selective vulnerability. PMID:25844330

  3. Asymmetric double-well potential for single-atom interferometry

    International Nuclear Information System (INIS)

    We consider the evolution of a single-atom wave function in a time-dependent double-well interferometer in the presence of a spatially asymmetric potential. We examine a case where a single trapping potential is split into an asymmetric double well and then recombined again. The interferometer involves a measurement of the first excited state population as a sensitive measure of the asymmetric potential. Based on a two-mode approximation a Bloch vector model provides a simple and satisfactory description of the dynamical evolution. We discuss the roles of adiabaticity and asymmetry in the double-well interferometer. The Bloch model allows us to account for the effects of asymmetry on the excited state population throughout the interferometric process and to choose the appropriate splitting, holding, and recombination periods in order to maximize the output signal. We also compare the outcomes of the Bloch vector model with the results of numerical simulations of the multistate time-dependent Schroedinger equation

  4. Affective privilege: Asymmetric interference by emotional distracters

    Directory of Open Access Journals (Sweden)

    Crystal eReeck

    2011-09-01

    Full Text Available Numerous theories posit that affectively salient stimuli are privileged in their capacity to capture attention and disrupt ongoing cognition. Two underlying assumptions in this theoretical position are that the potency of affective stimuli transcends task boundaries (i.e., emotional distracters do not have to belong to a current task-set to disrupt processing and that there is an asymmetry between emotional and cognitive processing (i.e., emotional distracters disrupt cognitive processing, but not vice versa. These assumptions have remained largely untested, as common experimental probes of emotion-cognition interaction rarely manipulate task-relevance and only examine one side of the presumed asymmetry of interference. To test these propositions directly, a face-word Stroop protocol was adapted to independently manipulate (a the congruency between target and distracter stimulus features, (b the affective salience of distracter features, and (c the task-relevance of emotional compared to non-emotional target features. A three-way interaction revealed interdependent effects of distracter relevance, congruence, and affective salience. Compared to task-irrelevant distracters, task-relevant congruent distracters facilitated performance and task-relevant incongruent distracters impaired performance, but the latter effect depended on the nature of the target feature and task. Specifically, task-irrelevant emotional distracters resulted in equivalent performance costs as task-relevant non-emotional distracters, whereas task-irrelevant non-emotional distracters did not produce performance costs comparable to those generated by task-relevant emotional distracters. These results document asymmetric cross-task interference effects for affectively salient stimuli, supporting the notion of affective prioritization in human information processing.

  5. Renewable resource management under asymmetric information

    DEFF Research Database (Denmark)

    Jensen, Frank; Andersen, Peder; Nielsen, Max

    2013-01-01

    Asymmetric information between fishermen and the regulator is important within fisheries. The regulator may have less information about stock sizes, prices, costs, effort, productivity and catches than fishermen. With asymmetric information, a strong analytical tool is principal-agent analysis....... In this paper, we study asymmetric information about productivity within a principal-agent framework and a tax on fishing effort is considered. It is shown that a second best optimum can be achieved if the effort tax is designed such that low-productivity agents rent is exhausted, while high-productivity agents...... receive an information rent. The information rent is equivalent to the total incentive cost. The incentive costs arise as we want to reveal the agent's type....

  6. Dc SQUIDs with asymmetric shunt resistors

    Energy Technology Data Exchange (ETDEWEB)

    Rudolph, Matthias; Nagel, Joachim; Kemmler, Matthias; Koelle, Dieter; Kleiner, Reinhold [Physikalisches Institut - Experimentalphysik II and Center for Collective Quantum Phenomena in LISAplus, Universitaet Tuebingen (Germany); Meckbach, Johannes Maximilian; Ilin, Konstantin; Siegel, Michael [Institut fuer Mikro- und Nanoelektronische Systeme, Karlsruhe Institute of Technology, Karlsruhe (Germany)

    2013-07-01

    We have investigated asymmetrically shunted Nb/Al-AlO{sub x}/Nb dc SQUIDs. Simulations based on the coupled Langevin equations predict that the optimum energy resolution ε, and thus also the noise performance of such an asymmetric SQUID, can be 3-4 times better than that of its symmetric counterpart. While keeping the total resistance R identical to a comparable symmetric SQUID with R{sup -1} = R{sub 1}{sup -1} + R{sub 2}{sup -1}, we shunted only one of the two Josephson junctions with R = R{sub 1,2}/2. Both types of SQUIDs were characterized with respect to their transport and noise properties at temperature T = 4.2 K, and we compared the experimental results with numerical simulations. Experiments yielded ε ∼ 32 ℎ for an asymmetric SQUID with an inductance L = 22 pH, whereas a comparable symmetric device achieved ε = 110 ℎ.

  7. Asymmetric membrane osmotic capsules for terbutaline sulphate

    Directory of Open Access Journals (Sweden)

    N G Gobade

    2012-01-01

    Full Text Available The aim of the present study was to design an asymmetric membrane capsule, an osmotic pump-based drug delivery system of ethyl cellulose for controlled release of terbutaline sulphate. asymmetric membrane capsules contains pore-forming water soluble additive, sorbitol in different concentrations in the capsule shell membrane, which after coming in contact with water, dissolves, resulting in an in situ formation of a microporous structure. The terbutaline sulphate is a β-adrenoreceptor agonist widely used in the treatment of asthma. The oral dosage regimen of terbutaline sulphate is 5 mg twice or thrice daily, the plasma half-life is approximate 3-4 h and it produces GI irritation with extensive first pass metabolism. Hence, terbutaline sulphate was chosen as a model drug with an aim to develop controlled release system. Different formulations of ethyl cellulose were prepared by phase inversion technique using different concentrations of sorbitol as pore forming agent. It was found that the thickness of the prepared asymmetric membrane capsules was increased with increase in concentration of ethyl cellulose and pore forming agent, i.e. sorbitol. The dye release study in water and 10% sodium chloride solution indicates that, the asymmetric membrane capsules follow osmotic principle to release content. The pores formed due to sorbitol were confirmed by microscopic observation of transverse section of capsule membrane. Data of in vitro release study of terbutaline sulphate from asymmetric membrane capsules indicated that, the capsules prepared with 10% and 12.5% of ethyl cellulose and 25% of sorbitol released as much as 97.44% and 76.27% in 12 h, respectively with zero order release rate. Hence asymmetric membrane capsule of 10% ethyl cellulose and 25% of sorbitol is considered as optimum for controlled oral delivery of terbutaline sulphate.

  8. Asymmetric membrane osmotic capsules for terbutaline sulphate.

    Science.gov (United States)

    Gobade, N G; Koland, Marina; Harish, K H

    2012-01-01

    The aim of the present study was to design an asymmetric membrane capsule, an osmotic pump-based drug delivery system of ethyl cellulose for controlled release of terbutaline sulphate. asymmetric membrane capsules contains pore-forming water soluble additive, sorbitol in different concentrations in the capsule shell membrane, which after coming in contact with water, dissolves, resulting in an in situ formation of a microporous structure. The terbutaline sulphate is a β-adrenoreceptor agonist widely used in the treatment of asthma. The oral dosage regimen of terbutaline sulphate is 5 mg twice or thrice daily, the plasma half-life is approximate 3-4 h and it produces GI irritation with extensive first pass metabolism. Hence, terbutaline sulphate was chosen as a model drug with an aim to develop controlled release system. Different formulations of ethyl cellulose were prepared by phase inversion technique using different concentrations of sorbitol as pore forming agent. It was found that the thickness of the prepared asymmetric membrane capsules was increased with increase in concentration of ethyl cellulose and pore forming agent, i.e. sorbitol. The dye release study in water and 10% sodium chloride solution indicates that, the asymmetric membrane capsules follow osmotic principle to release content. The pores formed due to sorbitol were confirmed by microscopic observation of transverse section of capsule membrane. Data of in vitro release study of terbutaline sulphate from asymmetric membrane capsules indicated that, the capsules prepared with 10% and 12.5% of ethyl cellulose and 25% of sorbitol released as much as 97.44% and 76.27% in 12 h, respectively with zero order release rate. Hence asymmetric membrane capsule of 10% ethyl cellulose and 25% of sorbitol is considered as optimum for controlled oral delivery of terbutaline sulphate. PMID:23204625

  9. Homogeneous asymmetric catalysis in fragrance chemistry.

    Science.gov (United States)

    Ciappa, Alessandra; Bovo, Sara; Bertoldini, Matteo; Scrivanti, Alberto; Matteoli, Ugo

    2008-06-01

    Opposite enantiomers of a chiral fragrance may exhibit different olfactory activities making a synthesis in high enantiomeric purity commercially and scientifically interesting. Accordingly, the asymmetric synthesis of four chiral odorants, Fixolide, Phenoxanol, Citralis, and Citralis Nitrile, has been investigated with the aim to develop practically feasible processes. In the devised synthetic schemes, the key step that leads to the formation of the stereogenic center is the homogeneous asymmetric hydrogenation of a prochiral olefin. By an appropriate choice of the catalyst and the reaction conditions, Phenoxanol, Citralis, and Citralis Nitrile were obtained in high enantiomeric purity, and odor profiles of the single enantiomers were determined.

  10. Asymmetric catalysis with short-chain peptides.

    Science.gov (United States)

    Lewandowski, Bartosz; Wennemers, Helma

    2014-10-01

    Within this review article we describe recent developments in asymmetric catalysis with peptides. Numerous peptides have been established in the past two decades that catalyze a wide variety of transformations with high stereoselectivities and yields, as well as broad substrate scope. We highlight here catalytically active peptides, which have addressed challenges that had thus far remained elusive in asymmetric catalysis: enantioselective synthesis of atropoisomers and quaternary stereogenic centers, regioselective transformations of polyfunctional substrates, chemoselective transformations, catalysis in-flow and reactions in aqueous environments.

  11. Asymmetric counter propagation of domain walls

    Science.gov (United States)

    Andrade-Silva, I.; Clerc, M. G.; Odent, V.

    2016-07-01

    Far from equilibrium systems show different states and domain walls between them. These walls, depending on the type of connected equilibria, exhibit a rich spatiotemporal dynamics. Here, we investigate the asymmetrical counter propagation of domain walls in an in-plane-switching cell filled with a nematic liquid crystal. Experimentally, we characterize the shape and speed of the domain walls. Based on the molecular orientation, we infer that the counter propagative walls have different elastic deformations. These deformations are responsible of the asymmetric counter propagating fronts. Theoretically, based on symmetry arguments, we propose a simple bistable model under the influence of a nonlinear gradient, which qualitatively describes the observed dynamics.

  12. Asymmetric acoustic transmission in multiple frequency bands

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Hong-xiang, E-mail: jsdxshx@ujs.edu.cn [Research Center of Fluid Machinery Engineering and Technology, Jiangsu University, Zhenjiang 212013 (China); Laboratory of Modern Acoustics, Institute of Acoustics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093 (China); State Key Laboratory of Acoustics, Institute of Acoustics, Chinese Academy of Sciences, Beijing 100190 (China); Yuan, Shou-qi, E-mail: Shouqiy@ujs.edu.cn [Research Center of Fluid Machinery Engineering and Technology, Jiangsu University, Zhenjiang 212013 (China); Zhang, Shu-yi [Laboratory of Modern Acoustics, Institute of Acoustics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093 (China)

    2015-11-23

    We report both experimentally and numerically that the multi-band device of the asymmetric acoustic transmission is realized by placing two periodic gratings with different periods on both sides of two brass plates immersed in water. The asymmetric acoustic transmission can exist in four frequency bands below 1500 kHz, which arises from the interaction between various diffractions from the two gratings and Lamb modes in the brass plates immersed in water. The results indicate that the device has the advantages of multiple band, broader bandwidth, and simpler structure. Our finding should have great potential applications in ultrasonic devices.

  13. Cell-sized asymmetric lipid vesicles facilitate the investigation of asymmetric membranes

    Science.gov (United States)

    Kamiya, Koki; Kawano, Ryuji; Osaki, Toshihisa; Akiyoshi, Kazunari; Takeuchi, Shoji

    2016-09-01

    Asymmetric lipid giant vesicles have been used to model the biochemical reactions in cell membranes. However, methods for producing asymmetric giant vesicles lead to the inclusion of an organic solvent layer that affects the mechanical and physical characteristics of the membrane. Here we describe the formation of asymmetric giant vesicles that include little organic solvent, and use them to investigate the dynamic responses of lipid molecules in the vesicle membrane. We formed the giant vesicles via the inhomogeneous break-up of a lipid microtube generated by applying a jet flow to an asymmetric planar lipid bilayer. The asymmetric giant vesicles showed a lipid flip-flop behaviour in the membrane, superficially similar to the lipid flip-flop activity observed in apoptotic cells. In vitro synthesis of membrane proteins into the asymmetric giant vesicles revealed that the lipid asymmetry in bilayer membranes improves the reconstitution ratio of membrane proteins. Our asymmetric giant vesicles will be useful in elucidating lipid–lipid and lipid–membrane protein interactions involved in the regulation of cellular functions.

  14. GENERATION OF ASYMMETRIC F-v CHARACTERISTICS FOR SYMMETRIC MR DAMPERS

    Institute of Scientific and Technical Information of China (English)

    WANG Enrong; YE Biaoming; MA Xiaoqing; SU Chunyi; RAKHEJA Subhash

    2006-01-01

    An asymmetric damping force generation algorithm is originally proposed to yield the asymmetric force-velocity characteristics for the symmetric magneto-rheological (MR) dampers. The command current is formulated in an asymmetric manner to excite the symmetric MR dampers by employing the "on-off" control law in response to the direction of velocity, and a smooth modulation function is developed without phase shift to suppress strong transients in the damping forces caused by the current-switching discontinuity. The effectiveness of the proposed algorithm is evaluated by analyzing the dynamic responses of a quarter-vehicle suspension system with a symmetric MR-damper by modulating the command current into the asymmetric manner. The simulation results show that the proposed algorithm could achieve a better compromise between the conflicting requirements of the asymmetric damping force ratio and the force-velocity curve smoothness, and the asymmetric damping MR-suspension design can ideally improve the road holding and ride performances of vehicle motion. The proposed algorithm can be generally incorporated with a controller synthesis to realize an intelligent vehicle suspension design with the symmetric MR dampers.

  15. Asymmetric interjoint feedback contributes to postural control of redundant multi-link systems

    Science.gov (United States)

    Bunderson, Nathan E.; Ting, Lena H.; Burkholder, Thomas J.

    2007-09-01

    Maintaining the postural configuration of a limb such as an arm or leg is a fundamental neural control task that involves the coordination of multiple linked body segments. Biological systems are known to use a complex network of inter- and intra-joint feedback mechanisms arising from muscles, spinal reflexes and higher neuronal structures to stabilize the limbs. While previous work has shown that a small amount of asymmetric heterogenic feedback contributes to the behavior of these systems, a satisfactory functional explanation for this non-conservative feedback structure has not been put forth. We hypothesized that an asymmetric multi-joint control strategy would confer both an energetic and stability advantage in maintaining endpoint position of a kinematically redundant system. We tested this hypothesis by using optimal control models incorporating symmetric versus asymmetric feedback with the goal of maintaining the endpoint location of a kinematically redundant, planar limb. Asymmetric feedback improved endpoint control performance of the limb by 16%, reduced energetic cost by 21% and increased interjoint coordination by 40% compared to the symmetric feedback system. The overall effect of the asymmetry was that proximal joint motion resulted in greater torque generation at distal joints than vice versa. The asymmetric organization is consistent with heterogenic stretch reflex gains measured experimentally. We conclude that asymmetric feedback has a functionally relevant role in coordinating redundant degrees of freedom to maintain the position of the hand or foot.

  16. Chilly dark sectors and asymmetric reheating

    Science.gov (United States)

    Adshead, Peter; Cui, Yanou; Shelton, Jessie

    2016-06-01

    In a broad class of theories, the relic abundance of dark matter is determined by interactions internal to a thermalized dark sector, with no direct involvement of the Standard Model (SM). We point out that these theories raise an immediate cosmological question: how was the dark sector initially populated in the early universe? Motivated in part by the difficulty of accommodating large amounts of entropy carried in dark radiation with cosmic microwave background measurements of the effective number of relativistic species at recombination, N eff , we aim to establish which admissible cosmological histories can populate a thermal dark sector that never reaches thermal equilibrium with the SM. The minimal cosmological origin for such a dark sector is asymmetric reheating, when the same mechanism that populates the SM in the early universe also populates the dark sector at a lower temperature. Here we demonstrate that the resulting inevitable inflaton-mediated scattering between the dark sector and the SM can wash out a would-be temperature asymmetry, and establish the regions of parameter space where temperature asymmetries can be generated in minimal reheating scenarios. Thus obtaining a temperature asymmetry of a given size either restricts possible inflaton masses and couplings or necessitates a non-minimal cosmology for one or both sectors. As a side benefit, we develop techniques for evaluating collision terms in the relativistic Boltzmann equation when the full dependence on Bose-Einstein or Fermi-Dirac phase space distributions must be retained, and present several new results on relativistic thermal averages in an appendix.

  17. Asymmetric Dimethyl Arginine in Hypothyroid Patients

    International Nuclear Information System (INIS)

    Thyroid diseases may lead to endothelial dysfunction, however, the mechanism underlying the endothelial dysfunction in thyroid disease is still not clear. Asymmetric dimethyl arginine (ADMA), a novel inhibitor of endothelial nitric oxide synthetase (eNOS), was reported to inhibit nitric oxide (NO) synthesis from L-arginine. The present study was carried out to investigate ADMA levels together with effects of dislipidemia in sub-clinical and overt hypothyroid females. There were significant increase in the levels of total cholesterol, low density lipoprotein-cholesterol (LDL-c), high density lipoprotein-cholesterol (HDL-c), thyroid stimulating hormone (TSH) and ADMA in hypothyroid females as compared to controls while the levels of NO and free T4 were significantly decreased than controls. Sub-clinical hypothyroid females had significant high TSH, LDL-c and non-significantly high ADMA levels and total cholesterol as compared to controls while they had significant decrease in NO, HDL-c and non-significant decrease in free T4 as compared to controls. There were significant negative correlations between NO and both ADMA (r2 = 0.84) and free T4 (r2 = 0.95) in overt hypothyroid group while significant positive correlation (r2 = 0.85) was detected between TSH and HDL-c in the same group. These results are highly suggestive that the decrease of nitric oxide secondary to accumulation of ADMA represent an important pathogenic factor together with dyslipidemia in endothelial dysfunction and increased cardiovascular risk especially in hypothyroid females

  18. 面包酵母催化不对称还原EOPB反应中的溶剂效应%Effect of organic solvents on asymmetric reduction of ethyl-2-oxo-4-phenylbutyrate mediated by saccharomyces cerevisiae

    Institute of Scientific and Technical Information of China (English)

    石玉刚; 励建荣; 唐琼

    2011-01-01

    The asymmetric reduction of ethyl-2-oxo-4-phenylbutyrate (EOPB) catalyzed by saccharomyces cerevisiae in organic phase to synthesize chiral ethyl-2-hydroxy-4-phenylbutyrate (EHPB) was investigated. In diethyl ether with the initial EOPB concentration of 6 mmol·L-1 , the e. e.(R)-EHPB was increased 19% by using wet baker's yeast (WB) as biocatalyst compared to that by dry baker's yeast (DB). However, the catalytic activity and stability of WB was lower than that of DB. The enantioselectivity of the reduction to produce (R) -EHPB was reduced with the increase of the log P value (0.82-3.2 ) of employed organic solvents. Although dimethylbenzene and cyclohexane had the same log p value (3.2), the enantioselectivity of the reduction was reversed from R to S when dimethylbenzene was in place of cyclohexane as reaction media. Significant changes were observed in the UV absorption and fluorescence spectrum of the YADH from the yeast pretreated by the solvents. These facts indicated that the synergistic effect of solvent polarity and its spatial structure led to the change of the catalytic behavior of baker's yeast%研究了非水介质中面包酵母催化不对称还原2-氧代-4-苯基丁酸乙酯(EOPB)合成手性2-羟基-4-苯36基丁酸乙酯(EHPB)的反应.乙醚体系中湿酵母(WB)催化6mmol·L-1EOPB合成(R)-EHPB的e.e.值较之于干酵母(DB)提高了近19%,但WB稳定性较差.DB催化该反应的立体选择性随溶剂logP(0.82-3.2)的增加而降低,反应从相同logP值(3.2)的二甲苯转换至环己烷后产物构型由R转为S,经有机溶剂预处理后酵母醇脱氢酶(YADH)的紫外及荧光光谱的特征变化表明溶剂分子极性与结构的协同作用下酵母催化行为发生了改变.

  19. Weak chaos in the asymmetric heavy top

    CERN Document Server

    Barrientos, M; Ranada, A F

    1995-01-01

    We consider the dynamics of the slightly asymmetric heavy top, a non-integrable system obtained from the Lagrange top by breaking the symmetry of its inertia tensor. It shows signs of weak chaos, which we study numerically. We argue that it is a good example for introducing students to non-integrability and chaos. (author)

  20. Asymmetric cell division: a persistent issue?

    OpenAIRE

    Aakre, Christopher D.; Laub, Michael T.

    2012-01-01

    Heterogeneity within a clonal population of cells can increase survival in the face of environmental stress. In a recent issue of Science, Aldridge et al. (2012) demonstrate that cell division in mycobacteria is asymmetric, producing daughter cells that differ in size, growth rate, and susceptibility to antibiotics.

  1. Asymmetric Total Synthesis of (-)-Cladospolide B

    Institute of Scientific and Technical Information of China (English)

    WANG,Wen-Kuan; ZHANG,Ji-Yong; HE,Jin-Mei; TANG,Shi-Bing; WANG,Xiao-Lei; SHE,Xue-Gong; PAN,Xin-Fu

    2008-01-01

    An enantioselective total synthesis of (-)-cladospolide B was described.The key steps in this synthesis include (a) a Sharpless asymmetric dihydroxylation to elaborate syn diol at C-4 and C-5 positions;(b) a Mitsunobu esterification to reverse the configuration at C-11 from (S) to (R);and (c) a ring-closing metathesis to access the 12-membered macrocyclic ring.

  2. Evidence of asymmetric top in 130Ba

    International Nuclear Information System (INIS)

    Introduced is a new relation connecting moment of inertia, Lipas parameter and asymmetric rotor model energies and put forward much closer trend in odd even staggering of quasi γ-band. A different view point regarding generation of quasi γ-band in 130Ba have been presented

  3. Detection loophole in asymmetric Bell experiments

    OpenAIRE

    Brunner, Nicolas; Gisin, Nicolas; Scarani, Valerio; Simon, Christoph

    2007-01-01

    The problem of closing the detection loophole with asymmetric systems, such as entangled atom-photon pairs, is addressed. We show that, for the Bell inequality I_3322, a minimal detection efficiency of 43% can be tolerated for one of the particles, if the other one is always detected. We also study the influence of noise and discuss the prospects of experimental implementation.

  4. Beam-beam issues in asymmetric colliders

    Energy Technology Data Exchange (ETDEWEB)

    Furman, M.A.

    1992-07-01

    We discuss generic beam-beam issues for proposed asymmetric e{sup +}- e{sup -} colliders. We illustrate the issues by choosing, as examples, the proposals by Cornell University (CESR-B), KEK, and SLAC/LBL/LLNL (PEP-II).

  5. Attentional Control and Asymmetric Associative Priming

    Science.gov (United States)

    Hutchison, Keith A.; Heap, Shelly J.; Neely, James H.; Thomas, Matthew A.

    2014-01-01

    Participants completed a battery of 3 attentional control (AC) tasks (OSPAN, antisaccade, and Stroop, as in Hutchison, 2007) and performed a lexical decision task with symmetrically associated (e.g., "sister-brother") and asymmetrically related primes and targets presented in both the forward (e.g., "atom-bomb") and backward…

  6. Catalytic asymmetric synthesis of mycocerosic acid

    NARCIS (Netherlands)

    ter Horst, B.; Feringa, B.L.; J. Minnaard, A.

    2007-01-01

    The first catalytic asymmetric total synthesis of mycocerosic acid was achieved via the application of iterative enantioselective 1,4-addition reactions and allows for the efficient construction of 1,3-polymethyl arrays with full stereocontrol; further exemplified by the synthesis of tetramethyl-dec

  7. Asymmetric relationships between proteins shape genome evolution.

    NARCIS (Netherlands)

    Notebaart, R.A.; Kensche, P.R.; Huynen, M.A.; Dutilh, B.E.

    2009-01-01

    BACKGROUND: The relationships between proteins are often asymmetric: one protein (A) depends for its function on another protein (B), but the second protein does not depend on the first. In metabolic networks there are multiple pathways that converge into one central pathway. The enzymes in the conv

  8. Standards vs. labels with imperfect competition and asymmetric information

    DEFF Research Database (Denmark)

    Baltzer, Kenneth Thomas

    I demonstrate that providing information about product quality is not necessarily the best way to address asymmetric information problems when markets are imperfectly competitive. In a vertical dierentiation model I show that a Minimum Quality Standard, which retains asymmetric information...

  9. Standards vs. labels with imperfect competition and asymmetric information

    DEFF Research Database (Denmark)

    Baltzer, Kenneth Thomas

    2012-01-01

    I demonstrate that providing information about product quality is not necessarily the best way to address asymmetric information problems when markets are imperfectly competitive. In a vertical differentiation model I show that a Minimum Quality Standard, which retains asymmetric information...

  10. Asymmetric Bulkheads for Cylindrical Pressure Vessels

    Science.gov (United States)

    Ford, Donald B.

    2007-01-01

    Asymmetric bulkheads are proposed for the ends of vertically oriented cylindrical pressure vessels. These bulkheads, which would feature both convex and concave contours, would offer advantages over purely convex, purely concave, and flat bulkheads (see figure). Intended originally to be applied to large tanks that hold propellant liquids for launching spacecraft, the asymmetric-bulkhead concept may also be attractive for terrestrial pressure vessels for which there are requirements to maximize volumetric and mass efficiencies. A description of the relative advantages and disadvantages of prior symmetric bulkhead configurations is prerequisite to understanding the advantages of the proposed asymmetric configuration: In order to obtain adequate strength, flat bulkheads must be made thicker, relative to concave and convex bulkheads; the difference in thickness is such that, other things being equal, pressure vessels with flat bulkheads must be made heavier than ones with concave or convex bulkheads. Convex bulkhead designs increase overall tank lengths, thereby necessitating additional supporting structure for keeping tanks vertical. Concave bulkhead configurations increase tank lengths and detract from volumetric efficiency, even though they do not necessitate additional supporting structure. The shape of a bulkhead affects the proportion of residual fluid in a tank that is, the portion of fluid that unavoidably remains in the tank during outflow and hence cannot be used. In this regard, a flat bulkhead is disadvantageous in two respects: (1) It lacks a single low point for optimum placement of an outlet and (2) a vortex that forms at the outlet during outflow prevents a relatively large amount of fluid from leaving the tank. A concave bulkhead also lacks a single low point for optimum placement of an outlet. Like purely concave and purely convex bulkhead configurations, the proposed asymmetric bulkhead configurations would be more mass-efficient than is the flat

  11. Charge Asymmetric Cosmic Rays as a probe of Flavor Violating Asymmetric Dark Matter

    DEFF Research Database (Denmark)

    Masina, Isabella; Sannino, Francesco

    2011-01-01

    The recently introduced cosmic sum rules combine the data from PAMELA and Fermi-LAT cosmic ray experiments in a way that permits to neatly investigate whether the experimentally observed lepton excesses violate charge symmetry. One can in a simple way determine universal properties of the unknown...... component of the cosmic rays. Here we attribute a potential charge asymmetry to the dark sector. In particular we provide models of asymmetric dark matter able to produce charge asymmetric cosmic rays. We consider spin zero, spin one and spin one-half decaying dark matter candidates. We show that lepton...... flavor violation and asymmetric dark matter are both required to have a charge asymmetry in the cosmic ray lepton excesses. Therefore, an experimental evidence of charge asymmetry in the cosmic ray lepton excesses implies that dark matter is asymmetric....

  12. High Order Centrifugal Distortion Corrections to Energy Levels of Asymmetric Top Molecules

    Institute of Scientific and Technical Information of China (English)

    LIU Yu-Yan; LIU Xiao-Yong; LIU Hong-Ping; GUO Yuan-Qing; HUANG Guang-Ming; LIN Jie-Li; GAO Hui

    2000-01-01

    High order centrifugal distortion terms have been derived and added to the effective Hamiltonian of asymmetric top molecules. Based on this Hamiltonian, a program in Fortran 77 has been developed for spectral analysis of asymmetric top molecules. The high order centrifugal distortion terms are found to be non-negligible even for the low-lying rotational transitions of molecules, such as Ha 18O, subjected to severe centrifugal distortion effect,and for the high-lying rotational transitions of molecules, such as 14N16O2 subjected to the moderate centrifugal distortion effect.

  13. Interaction modes between asymmetrically and oppositely charged rods.

    Science.gov (United States)

    Antila, Hanne S; Van Tassel, Paul R; Sammalkorpi, Maria

    2016-02-01

    The interaction of oppositely and asymmetrically charged rods in salt-a simple model of (bio)macromolecular assembly-is observed via simulation to exhibit two free energy minima, separated by a repulsive barrier. In contrast to similar minima in the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory, the governing mechanism includes electrostatic attraction at large separation, osmotic repulsion at close range, and depletion attraction near contact. A model accounting for ion condensation and excluded volume is shown to be superior to a mean-field treatment in predicting the effect of charge asymmetry on the free-energy profile. PMID:26986372

  14. Adaptive synchronization in an array of asymmetric coupled neural networks

    Institute of Scientific and Technical Information of China (English)

    Gao Ming; Cui Bao-Tong

    2009-01-01

    This paper investigates the global synchronization in an array of linearly coupled neural networks with constant and delayed coupling. By a simple combination of adaptive control and linear feedback with the updated laws, some sufficient conditions are derived for global synchronization of the coupled neural networks. The coupling configuration matrix is assumed to be asymmetric, which is more coincident with the realistic network. It is shown that the approaches developed here extend and improve the earlier works. Finally, numerical simulations are presented to demonstrate the effectiveness of the theoretical results.

  15. Crystallization of asymmetric patchy models for globular proteins in solution

    Science.gov (United States)

    Fusco, Diana; Charbonneau, Patrick

    2013-07-01

    Asymmetric patchy particle models have recently been shown to describe the crystallization of small globular proteins with near-quantitative accuracy. Here, we investigate how asymmetry in patch geometry and bond energy generally impacts the phase diagram and nucleation dynamics of this family of soft matter models. We find the role of the geometry asymmetry to be weak, but the energy asymmetry to markedly interfere with the crystallization thermodynamics and kinetics. These results provide a rationale for the success and occasional failure of the proposal of George and Wilson for protein crystallization conditions as well as physical guidance for developing more effective protein crystallization strategies.

  16. A joint asymmetric watermarking and image encryption scheme

    Science.gov (United States)

    Boato, G.; Conotter, V.; De Natale, F. G. B.; Fontanari, C.

    2008-02-01

    Here we introduce a novel watermarking paradigm designed to be both asymmetric, i.e., involving a private key for embedding and a public key for detection, and commutative with a suitable encryption scheme, allowing both to cipher watermarked data and to mark encrypted data without interphering with the detection process. In order to demonstrate the effectiveness of the above principles, we present an explicit example where the watermarking part, based on elementary linear algebra, and the encryption part, exploiting a secret random permutation, are integrated in a commutative scheme.

  17. Interaction modes between asymmetrically and oppositely charged rods.

    Science.gov (United States)

    Antila, Hanne S; Van Tassel, Paul R; Sammalkorpi, Maria

    2016-02-01

    The interaction of oppositely and asymmetrically charged rods in salt-a simple model of (bio)macromolecular assembly-is observed via simulation to exhibit two free energy minima, separated by a repulsive barrier. In contrast to similar minima in the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory, the governing mechanism includes electrostatic attraction at large separation, osmotic repulsion at close range, and depletion attraction near contact. A model accounting for ion condensation and excluded volume is shown to be superior to a mean-field treatment in predicting the effect of charge asymmetry on the free-energy profile.

  18. Asymmetric Synthesis of (R)-and (S)-Moprolol

    Institute of Scientific and Technical Information of China (English)

    WANG Zhao-yang; WANG Yan; SUN Li-wen; ZHU Jin-tao

    2008-01-01

    A simple and effective procedure for the enantioselective synthesis of (R)-and (S)-moprolol was described.The key step was the asymmetric synthesis of enantiopure (R)-and (S)-guaifenesin,which were synthesized from enantioenriched (R)-3-chloro-1,2-propanediol and (S)-epichlorohydrin via kinetics of hydrolysis resolution of racemic epichlorohydrin by chiral Salen-CoIIII complex.The e.e.values of both the optical compounds were above 98%,and the chemical structures of the target compounds were confirmed by 1H NMR,13C NMR,IR,and MS.

  19. Identification of Multimodel LPV Models with Asymmetric Gaussian Weighting Function

    Directory of Open Access Journals (Sweden)

    Jie You

    2013-01-01

    Full Text Available This paper is concerned with the identification of linear parameter varying (LPV systems by utilizing a multimodel structure. To improve the approximation capability of the LPV model, asymmetric Gaussian weighting functions are introduced and compared with commonly used symmetric Gaussian functions. By this mean, locations of operating points can be selected freely. It has been demonstrated through simulations with a high purity distillation column that the identified models provide more satisfactory approximation. Moreover, an experiment is performed on real HVAC (heating, ventilation, and air-conditioning to further validate the effectiveness of the proposed approach.

  20. Open bottom mesons in hot asymmetric hadronic medium

    OpenAIRE

    Pathak, Divakar; Mishra, Amruta

    2014-01-01

    The in-medium masses and optical potentials of $B$ and ${\\bar B}$ mesons are studied in an isospin asymmetric, strange, hot and dense hadronic environment using a chiral effective model. The chiral $SU(3)$ model originally designed for the light quark sector, is generalized to include the heavy quark sector ($c$ and $b$) to derive the interactions of the $B$ and ${\\bar B}$ mesons with the light hadrons. Due to large mass of bottom quark, we use only the empirical form of these interactions fo...

  1. Asymmetric plasmonic induced ionic noise in metallic nanopores

    Science.gov (United States)

    Li, Yi; Chen, Chang; Willems, Kherim; Lagae, Liesbet; Groeseneken, Guido; Stakenborg, Tim; van Dorpe, Pol

    2016-06-01

    We present distinct asymmetric plasmon-induced noise properties of ionic transport observed through gold coated nanopores. We thoroughly investigated the effects of bias voltage and laser illumination. We show that the potential drop across top-coated silicon nanocavity pores can give rise to a large noise asymmetry (~2-3 orders of magnitude). Varying the bias voltage has an appreciable effect on the noise density spectra, typically in the Lorentzian components. The laser power is found to strongly affect the ionic noise level as well as the voltage threshold for light-induced noise generation. The asymmetric noise phenomenon is attributed to plasmon-induced interfacial reactions which promote light-induced charge fluctuation in the ion flow and allow voltage modulation of photo-induced carriers surmounting over such Schottky junctions. We further compare the ionic noise performances of gold nanocavities containing different material stacks, among which thermal oxide passivation of the silicon successfully mitigates the light-induced noise and is also fully CMOS-compatible. The understanding of the described noise characteristics will help to foster multiple applications using related structures including plasmonic-based sensing or plasmon-induced catalysis such as water splitting or solar energy conversion devices.We present distinct asymmetric plasmon-induced noise properties of ionic transport observed through gold coated nanopores. We thoroughly investigated the effects of bias voltage and laser illumination. We show that the potential drop across top-coated silicon nanocavity pores can give rise to a large noise asymmetry (~2-3 orders of magnitude). Varying the bias voltage has an appreciable effect on the noise density spectra, typically in the Lorentzian components. The laser power is found to strongly affect the ionic noise level as well as the voltage threshold for light-induced noise generation. The asymmetric noise phenomenon is attributed to plasmon

  2. Interaction modes between asymmetrically and oppositely charged rods

    Science.gov (United States)

    Antila, Hanne S.; Van Tassel, Paul R.; Sammalkorpi, Maria

    2016-02-01

    The interaction of oppositely and asymmetrically charged rods in salt—a simple model of (bio)macromolecular assembly—is observed via simulation to exhibit two free energy minima, separated by a repulsive barrier. In contrast to similar minima in the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory, the governing mechanism includes electrostatic attraction at large separation, osmotic repulsion at close range, and depletion attraction near contact. A model accounting for ion condensation and excluded volume is shown to be superior to a mean-field treatment in predicting the effect of charge asymmetry on the free-energy profile.

  3. Quantum Stackelberg Duopoly of Continuous Distributed Asymmetric Information

    Institute of Scientific and Technical Information of China (English)

    WANG Xia; YANG Xiao-Hua; MIAO Lin; ZHOU Xiang; HU Cheng-Zheng

    2007-01-01

    The minimal quantization structure is employed to investigate the quantum version of the Stackelberg duopoly with continuous distributed asymmetric information, I.e. The first mover has incomplete information that obeys a continuous distribution while the second mover has complete information. It is found that the effects of the positive quantum entanglement on the outcomes exhibit many interesting features due to the information asymmetry. Moreover, although the first-mover advantage is counteracted by the information asymmetry, the positive quantum entanglement still enhances the first-mover advantage and improves the first-mover tolerance of the information asymmetry beyond the classical limit.

  4. Neutron-proton mass difference in isospin asymmetric nuclear matter

    CERN Document Server

    Meißner, Ulf-G; Wirzba, A; Yakhshiev, U T

    2007-01-01

    Isospin-breaking effects in the baryonic sector are studied in the framework of a medium-modified Skyrme model. The neutron-proton mass difference in infinite, asymmetric nuclear matter is discussed. In order to describe the influence of the nuclear environment on the skyrmions, we include energy-dependent charged and neutral pion optical potentials in the s- and p-wave channels. The present approach predicts that the neutron-proton mass difference is mainly dictated by its strong part and that it strongly decreases in neutron matter.

  5. Carbon nanotube intramolecular p-i-n junction diodes with symmetric and asymmetric contacts

    Science.gov (United States)

    Chen, Changxin; Liao, Chenghao; Wei, Liangming; Zhong, Hanqing; He, Rong; Liu, Qinran; Liu, Xiaodong; Lai, Yunfeng; Song, Chuanjuan; Jin, Tiening; Zhang, Yafei

    2016-01-01

    A p-i-n junction diode based on the selectively doped single-walled carbon nanotube (SWCNT) had been investigated, in which two opposite ends of individual SWCNT channel were doped into the p- and n-type SWCNT respectively while the middle segment of SWCNT was kept as the intrinsic. The symmetric and asymmetric contacts were used to fabricate the p-i-n junction diodes respectively and studied the effect of the contact on the device characteristics. It was shown that a low reverse saturation current of ~20 pA could be achieved by these both diodes. We found that the use of the asymmetric contact can effectively improve the performance of the p-i-n diode, with the rectification ratio enhanced from ~102 for the device with the Au/Au symmetric contact to >103 for the one with the Pd/Al asymmetric contact. The improvement of the device performance by the asymmetric-contact structure was attributed to the decrease of the effective Schottky-barrier height at the contacts under forward bias, increasing the forward current of the diode. The p-i-n diode with asymmetric contact also had a higher rectification ratio than its counterpart before doping the SWCNT channel, which is because that the p-i-n junction in the device decreased the reverse saturated current. PMID:26915400

  6. Asymmetric impacts of international energy shocks on macroeconomic activities

    International Nuclear Information System (INIS)

    While limited by its scarcity of natural resources, the impacts of energy price changes on Taiwan's economic activities have been an important issue for social public and government authorities. This study applies the multivariate threshold model to investigate the effects of various international energy price shocks on Taiwan's macroeconomic activity. By separating energy price changes into the so-called decrease and increase regimes, we can realize different impacts of energy price changes and their shocks on economic output. The results confirm that there is an asymmetric threshold effect for the energy-output nexus. The optimal threshold levels are exactly where the oil price change is at 2.48%, the natural gas price change is at 0.66%, and the coal price change is at 0.25%. The impulse response analysis suggests that oil price and natural gas shocks have a delayed negative impact on macroeconomic activities. - Highlights: ► This study applies multivariate threshold model to investigate the effects of various international energy price shocks on Taiwan's macroeconomic activity. ► The results confirm that there is an asymmetric threshold effect for energy-output nexus. ► The optimal threshold levels are exactly found where oil price change is at 2.48%, natural gas price change is at 0.66%, and coal price change is at 0.25%.

  7. Modeling of severe deformation and mechanical properties in Mg-3A1-1Zn alloy through asymmetric hot-extrusion

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    One-pass asymmetric hot extrusion performed at 673 K was applied to fabricate an AZ31 magnesium alloy sheet.Finite element method(FEM)was used to model the process of asymmetric hot-extrusion.Simulation results indicate that strain rate gradient througa the thickness introduced a grain size gradient along the thickness direction and shear deformation during the asymmetric hot-extrusion results in weakened and tilted(0002)basal texture.The asymmetric hot extrusion effectively weakens the basal texture and improves the ductility,at room temperature.

  8. Route-asymmetrical light transmission of a fiber-chip-fiber optomechanical system

    DEFF Research Database (Denmark)

    Liu, Li; Ding, Yunhong; Cai, Xinlun;

    2016-01-01

    . Employing a fiber-chip-fiber optomechanical system, our scheme has successfully achieved a broad operation bandwidth of at least 24 nm and an ultra-high route-asymmetrical transmission ratio (RATR) up to 63 dB. The route-asymmetrical device has been demonstrated effectively with not only the continuous......-wave (CW) light but also 10 Gbit/s on-off-keying (OOK) digital signals. Above mentioned unique features can be mostly attributed to the significant characteristics of the thermal radiative effect, which could cause a fiber displacement up to tens of microns. The powerful and significant thermal radiative...

  9. L-Tartaric Acid as a New Chiral Auxiliary for Asymmetric Synthesis of Piperazinones, Morpholinones, Dihydroquinoxalinones and Dihydrobenzoxazinones

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yelim; Park, Kon Ji; Park, Yong Sun [Konkuk Univ., Seoul (Korea, Republic of)

    2012-11-15

    We have reported the dynamic resolution of α-bromo esters in nucleophilic substitution using L-tartaric acid derivatives as a new effective chiral auxiliary. In the substitutions with ethylenediamine and 2-aminoethanol nucleophiles, spontaneous cyclization can provide a convenient procedure for asymmetric syntheses of 3-substituted piperazin-2-ones and morpholin-2-ones. In addition, the substitutions with arylamine nucleophiles such as 1,2-diaminobenzene and 2-aminophenol can provide an efficient method for asymmetric syntheses of dihydroquinoxalinones and dihydrobenzoxazinones. The simple protocol with mild condition suggests further applications to asymmetric syntheses of various heterocyclic compounds.

  10. Geometrical effect on the issue of asymmetric C 1s photoelectron angular distributions detected in coincidence with the fragment ion pairs of CO+–O+ for CO2 molecules

    International Nuclear Information System (INIS)

    We have measured C 1s photoelectron angular distributions (PADs) in coincidence with the CO+–O+ fragment ion pairs of CO2 molecules at the photoelectron energies of 85, 120 and 150 eV. The observed left–right asymmetric PADs have been well reproduced by our theoretical model taking into account the two degenerate zero-point bending vibrations. This leads to a conclusive result on the interpretation of such PADs; although it has been believed so far that they are the molecular frame, in fact they are the recoil frame. (fast track communications)

  11. Measurement and understanding of single-molecule break junction rectification caused by asymmetric contacts.

    Science.gov (United States)

    Wang, Kun; Zhou, Jianfeng; Hamill, Joseph M; Xu, Bingqian

    2014-08-01

    The contact effects of single-molecule break junctions on rectification behaviors were experimentally explored by a systematic control of anchoring groups of 1,4-disubstituted benzene molecular junctions. Single-molecule conductance and I-V characteristic measurements reveal a strong correlation between rectifying effects and the asymmetry in contacts. Analysis using energy band models and I-V calculations suggested that the rectification behavior is mainly caused by asymmetric coupling strengths at the two contact interfaces. Fitting of the rectification ratio by a modified Simmons model we developed suggests asymmetry in potential drop across the asymmetric anchoring groups as the mechanism of rectifying I-V behavior. This study provides direct experimental evidence and sheds light on the mechanisms of rectification behavior induced simply by contact asymmetry, which serves as an aid to interpret future single-molecule electronic behavior involved with asymmetric contact conformation.

  12. Chemoepitaxial guiding underlayers for density asymmetric and energetically asymmetric diblock copolymers

    Science.gov (United States)

    Nation, Benjamin D.; Ludovice, Peter J.; Henderson, Clifford L.

    2016-04-01

    Block copolymers, polymers composed of two or more homopolymers covalently bonded together, are currently being investigated as a method to extend optical lithography due to their ability to microphase separate on small size scales. In order to drive down the size that these BCPs phase separate, the BCPs with larger Flory-Huggin's χparameter needs to be found. Typically these BCPs are composed of more dissimilar homopolymers. However, changing these interactions also changes how BCPs interact with their guiding underlayers. In this paper, several block copolymers are simulated annealing on chemoepitaxial guiding underlayers using a coarse-grained molecular dynamics model in order to explore the effect that either energetic asymmetry or density asymmetry in the BCP have on the pattern registration. It is found that energetic asymmetry in BCPs causes one of the blocks to desire to skin, which shifts the composition of the background region that leads to well aligned vertical lamellae formation. It is hypothesized that moderate footing and undercutting at the underlayer or slight skinning at the free surface can increase the kinetics of defect annihilation by decreasing the distance that bridges must form. The density asymmetric BCPs simulated in this paper have different mechanical properties which lead to straighter sidewalls in the BCP film and potentially lead to better pattern registration. It is hypothesized that altering the compressibility of the blocks can alter equilibrium defectivity.

  13. Design of Asymmetric Peptide Bilayer Membranes.

    Science.gov (United States)

    Li, Sha; Mehta, Anil K; Sidorov, Anton N; Orlando, Thomas M; Jiang, Zhigang; Anthony, Neil R; Lynn, David G

    2016-03-16

    Energetic insights emerging from the structural characterization of peptide cross-β assemblies have enabled the design and construction of robust asymmetric bilayer peptide membranes. Two peptides differing only in their N-terminal residue, phosphotyrosine vs lysine, coassemble as stacks of antiparallel β-sheets with precisely patterned charged lattices stabilizing the bilayer leaflet interface. Either homogeneous or mixed leaflet composition is possible, and both create nanotubes with dense negative external and positive internal solvent exposed surfaces. Cross-seeding peptide solutions with a preassembled peptide nanotube seed leads to domains of different leaflet architecture within single nanotubes. Architectural control over these cross-β assemblies, both across the bilayer membrane and along the nanotube length, provides access to highly ordered asymmetric membranes for the further construction of functional mesoscale assemblies.

  14. Enhancing molecule fluorescence with asymmetrical plasmonic antennas.

    Science.gov (United States)

    Lu, Guowei; Liu, Jie; Zhang, Tianyue; Shen, Hongming; Perriat, Pascal; Martini, Matteo; Tillement, Olivier; Gu, Ying; He, Yingbo; Wang, Yuwei; Gong, Qihuang

    2013-07-21

    We propose and justify by the finite-difference time-domain method an efficient strategy to enhance the spontaneous emission of a fluorophore with a multi-resonance plasmonic antenna. The custom-designed asymmetrical antenna consists of two plasmonic nanoparticles with different sizes and is able to couple efficiently to free space light through multiple localized surface plasmon resonances. This design simultaneously permits a large near-field excitation near the antenna as well as a high quantum efficiency, which results in an unusual and significant enhancement of the fluorescence of a single emitter. Such an asymmetrical antenna presents intrinsic advantages over single particle or dimer based antennas made using two identical nanostructures. This promising concept can be exploited in the large domain of light-matter interaction processes involving multiple frequencies.

  15. Applications of Chiral Anions in Asymmetric Catalysis

    OpenAIRE

    Hamilton, Gregory Lawrence

    2011-01-01

    The synthesis of molecules with control over their three-dimensional configuration, known as absolute stereochemistry, is one of the highest goals of synthetic organic chemists. As is so often the case, we strive to reach the facility and efficiency with which Nature achieves this goal. Fortunately, the chemist's imagination allows us to envision nearly unlimited possibilities for new modes of catalysis. In this dissertation, I discuss one branch of asymmetric catalysis that has in a short ti...

  16. New ruthenium catalysts for asymmetric hydrogenation

    OpenAIRE

    Diaz Valenzuela, Maria Belen

    2007-01-01

    A review on catalytic asymmetric hydrogenation of C=O double bonds is presented in the first chapter. Noyori’s pioneering research on ruthenium complexes containing both phosphine and diamine ligands using [i superscript]PrOH and [t superscript]BuOK is described, this system gave impressive highly chemeo-selectivity for C=O bonds and extremely high enantioselectivity for a range of acetophenone derivatives. Numerous groups have been inspired by Noyori’s catalyst of the ty...

  17. Competitive Price and Quality Under Asymmetric Information

    OpenAIRE

    Gerard J. Tellis; Birger Wernerfelt

    1987-01-01

    We present an analysis of equilibrium in markets with asymmetrically informed consumers. Some consumers know both price and quality of all sellers, whereas others know neither but may search among sellers. The equilibrium correlation between price and quality generally increases with the level of information in the market and can be negative when this level is sufficiently small. A meta-analysis of the available empirical studies strongly supports the model's predictions.

  18. Cosmological signatures of time-asymmetric gravity

    OpenAIRE

    Cortês, Marina; Liddle, Andrew R; Smolin, Lee

    2016-01-01

    We develop the model proposed by Cort\\^es, Gomes & Smolin, to predict cosmological signatures of time-asymmetric extensions of general relativity they proposed recently. Within this class of models the equation of motion of chiral fermions is modified by a torsion term. This term leads to a dispersion law for neutrinos that associates a new time-varying energy with each particle. We find a new neutrino contribution to the Friedmann equation resulting from the torsion term in the Ashtekar conn...

  19. Asymmetric inheritance of cytoophidia in Schizosaccharomyces pombe

    OpenAIRE

    Jing Zhang; Lydia Hulme; Ji-Long Liu

    2014-01-01

    ABSTRACT A general view is that Schizosaccharomyces pombe undergoes symmetric cell division with two daughter cells inheriting equal shares of the content from the mother cell. Here we show that CTP synthase, a metabolic enzyme responsible for the de novo synthesis of the nucleotide CTP, can form filamentous cytoophidia in the cytoplasm and nucleus of S. pombe cells. Surprisingly, we observe that both cytoplasmic and nuclear cytoophidia are asymmetrically inherited during cell division. Our t...

  20. Selective Homogeneous Catalysis in Asymmetric Synthesis

    DEFF Research Database (Denmark)

    Fristrup, Peter

    The subject of this thesis is selectivity in homogeneous asymmetric transition metalcatalyzed reactions. Four different reactions within organic chemistry have been studied by kinetic measurements, computational chemistry (modelling) or both of them in parallel. A Hammett study was performed....... A thorough computational study succeeded in explaining the observed results, although other significant results were also obtained during this study. Finally, an intramolecular reaction was studied computationally, and the rate increase observed under phase transfer catalysis conditions could be related...

  1. On asymmetric collisions with large disruption parameters

    International Nuclear Information System (INIS)

    Collisions between a weak electron bunch and a strong positron bunch are studied within a flat model. Electrons are tracked through the transverse space charge field of the positron bunch, and it is shown that positrons in a storage ring may remain stable after asymmetric collisions with a weak electron bunch in spite of large values of the electron disruption parameter. The plasma oscillations that affect collisions with large disruption parameters may be suppressed by properly matching the electrons. 8 refs., 5 figs

  2. Neuronal alignment on asymmetric textured surfaces

    OpenAIRE

    Beighley, Ross; Spedden, Elise; Sekeroglu, Koray; Atherton, Timothy; Demirel, Melik C.; Staii, Cristian

    2012-01-01

    Axonal growth and the formation of synaptic connections are key steps in the development of the nervous system. Here, we present experimental and theoretical results on axonal growth and interconnectivity in order to elucidate some of the basic rules that neuronal cells use for functional connections with one another. We demonstrate that a unidirectional nanotextured surface can bias axonal growth. We perform a systematic investigation of neuronal processes on asymmetric surfaces and quantify...

  3. Trapdoor Privacy in Asymmetric Searchable Encryption Schemes

    OpenAIRE

    Delerue Arriaga, Afonso; TANG, QIANG; Ryan, Peter

    2014-01-01

    Asymmetric searchable encryption allows searches to be carried over ciphertexts, through delegation, and by means of trapdoors issued by the owner of the data. Public Key Encryption with Keyword Search (PEKS) is a primitive with such functionality that provides delegation of exact-match searches. As it is important that ciphertexts preserve data privacy, it is also important that trapdoors do not expose the user’s search criteria. The difficulty of formalizing a security model for trapdoor pr...

  4. Legal Dilemmas in Fighting Asymmetrical Conflicts

    Directory of Open Access Journals (Sweden)

    Pnina Sharvit Baruch

    2012-04-01

    Full Text Available What legal rules apply to armed confrontations against non-state elements in areas populated by civilians? What rules apply when the enemy does not honor the basic laws of warfare - does not distinguish itself from the local population, and even uses it for shelter and as a base of operations? This essay, which presents my position on the issue, refers to such confrontations as "asymmetrical conflicts."

  5. Asymmetric Information – Adverse Selection Problem

    Directory of Open Access Journals (Sweden)

    Dumitru MARIN

    2007-01-01

    Full Text Available The present paper makes an introduction in the contract theory starting with the definitions of asymmetric information and some of the problems that generate: moral hazard and adverse selection. We provide an insight of the latest empirical studies in adverse selection in different markets. An adverse selection model, based on Rothchild and Stiglitz is also present to give a perspective of the theoretical framework.

  6. OFFICER AND COMMANDER IN ASYMMETRIC WARFARE OPERATIONS

    OpenAIRE

    Giuseppe CAFORIO

    2013-01-01

    Starting from the data of a field research conducted among soldiers with asymmetric warfare experiences from nine different countries, the author seeks to identify and shed light on the various problems that officers with command responsibilities had to face during their missions. A picture emerges of feelings and experiences relating to their first impression upon arriving in the theatre, relations with local armed forces, relations with the local population and local authorities, relations ...

  7. Ultralong distance coupling between asymmetric resonant microcavities

    OpenAIRE

    Shu, Fang-Jie; Zou, Chang-Ling; Chen, Wen-Cong; Sun, Fang-Wen

    2013-01-01

    The ultralong distance coupling between two Asymmetric Resonant Microcavities (ARCs) is studied. Different from traditional short distance tunneling coupling between microcavities, the high efficient free space directional emission and excitation allow ultralong distance energy transfer between ARCs. In this paper, a novel unidirectional emission ARC, which shows directionality I40 = 0.54, is designed for materials of refractive index n = 2.0. Compared with regular whispering gallery microres...

  8. Prospects for Asymmetric PNe with ALMA

    CERN Document Server

    Huggins, P J

    2010-01-01

    Millimeter and sub-millimeter observations have made fundamental contributions to our current understanding of the transition from AGB stars to white dwarfs. The approaching era of ALMA brings significantly enhanced observing capabilities at these wavelengths and promises to push back the frontiers in a number of ways. We examine the scientific prospects of this new era for PNe, with an emphasis on how developments may contribute to the goals of the asymmetric PNe community.

  9. Asymmetric Reversal in Inhomogeneous Magnetic Heterostructures

    OpenAIRE

    Li, Zhi-Pan; Petracic, Oleg; Morales, Rafael; Olamit, Justin; Batlle, Xavier; Liu, Kai; Schuller, Ivan K.

    2006-01-01

    Asymmetric magnetization reversal is an unusual phenomenon in antiferromagnet/ferromagnet (AF/FM) exchange biased bilayers. We investigated this phenomenon in a simple model system experimentally and by simulation assuming inhomogeneously distributed interfacial AF moments. The results suggest that the observed asymmetry originates from the intrinsic broken symmetry of the system, which results in local incomplete domain walls parallel to the interface in reversal to negative saturation of th...

  10. Multiple Traveling Salesmen in Asymmetric Metrics

    CERN Document Server

    Friggstad, Zachary

    2011-01-01

    We consider some generalizations of the Asymmetric Traveling Salesman Path problem. Suppose we have an asymmetric metric G = (V,A) with two distinguished nodes s,t. We are also given a positive integer k. The goal is to find k paths of minimum total cost from s to t whose union spans all nodes. We call this the k-Person Asymmetric Traveling Salesmen Path problem (k-ATSPP). Our main result for k-ATSPP is a bicriteria approximation that, for some parameter b >= 1 we may choose, finds between k and k + k/b paths of total length O(b log |V|) times the optimum value of an LP relaxation based on the Held-Karp relaxation for the Traveling Salesman problem. On one extreme this is an O(log |V|)-approximation that uses up to 2k paths and on the other it is an O(k log |V|)-approximation that uses exactly k paths. Next, we consider the case where we have k pairs of nodes (s_1,t_1), ..., (s_k,t_k). The goal is to find an s_i-t_i path for every pair such that each node of G lies on at least one of these paths. Simple appro...

  11. Asymmetric threat data mining and knowledge discovery

    Science.gov (United States)

    Gilmore, John F.; Pagels, Michael A.; Palk, Justin

    2001-03-01

    Asymmetric threats differ from the conventional force-on- force military encounters that the Defense Department has historically been trained to engage. Terrorism by its nature is now an operational activity that is neither easily detected or countered as its very existence depends on small covert attacks exploiting the element of surprise. But terrorism does have defined forms, motivations, tactics and organizational structure. Exploiting a terrorism taxonomy provides the opportunity to discover and assess knowledge of terrorist operations. This paper describes the Asymmetric Threat Terrorist Assessment, Countering, and Knowledge (ATTACK) system. ATTACK has been developed to (a) data mine open source intelligence (OSINT) information from web-based newspaper sources, video news web casts, and actual terrorist web sites, (b) evaluate this information against a terrorism taxonomy, (c) exploit country/region specific social, economic, political, and religious knowledge, and (d) discover and predict potential terrorist activities and association links. Details of the asymmetric threat structure and the ATTACK system architecture are presented with results of an actual terrorist data mining and knowledge discovery test case shown.

  12. Orientation of x-lines in asymmetric magnetic reconnection

    Science.gov (United States)

    Liu, Yi-Hsin; Hesse, Michael; Kuznetsova, Masha

    2015-11-01

    At Earth's magnetopause, reconnection proceeds asymmetrically between magnetosheath plasmas, namely solar wind plasmas compressed by Earth's bow shock, and magnetospheric plasmas. In an asymmetric configuration, it is unclear if there is a simple principle to determine the orientation of the x-line. Using fully kinetic simulations, we study this issue and a spatially localized perturbation is employed to induce a single x-line, that has sufficient freedom to choose its orientation in three-dimensional systems. The effect of ion to electron mass ratio is investigated, and the x-line appears to bisect the magnetic shear angle across the current sheet in the large mass ratio limit. The deviation from the bisection angle in the lower mass ratio limit can be explained by the physics of tearing instability. The local physics control of the x-line orientation studied in this slab geometry could potentially interplay with global geometrical effects to determine the location of collisionless magnetic reconnection at Earth's magnetopause.

  13. Collective modes in hot asymmetric nuclear matter at variable densities

    International Nuclear Information System (INIS)

    A nearly exact expression for the response function of hot asymmetric nuclear matter is derived for Skyrme type effective interactions and the resulting strength distribution is analyzed for the four channels of the particle-hole interaction. Several proton-neutron asymmetries are considered as well as different total densities. In the isovector channel the strength presents a very collective behaviour (zero sound type) which becomes still more collective with increasing asymmetry. For higher nuclear densities it may be collective or unstable depending on the effective interaction. This is also the behaviour for the spin-isospin channel. The other channels may have the collectivity increased for a highly asymmetric nuclear matter at higher densities. In the spin channel zero sound modes are found for higher enough p-n asymmetries and/or densities higher than the saturation density. The static limit of the polarizabilities are considered yielding the symmetry energy coefficients for isovector, spin and spin-isospin channels. The dependence of the polarizabilities on p-n asymmetry is analyzed, in particular in the isovector channel which is of interest, for example, for the supernovae mechanism

  14. Condensation on slippery asymmetric bumps

    Science.gov (United States)

    Park, Kyoo-Chul; Kim, Philseok; Grinthal, Alison; He, Neil; Fox, David; Weaver, James C.; Aizenberg, Joanna

    2016-03-01

    Controlling dropwise condensation is fundamental to water-harvesting systems, desalination, thermal power generation, air conditioning, distillation towers, and numerous other applications. For any of these, it is essential to design surfaces that enable droplets to grow rapidly and to be shed as quickly as possible. However, approaches based on microscale, nanoscale or molecular-scale textures suffer from intrinsic trade-offs that make it difficult to optimize both growth and transport at once. Here we present a conceptually different design approach—based on principles derived from Namib desert beetles, cacti, and pitcher plants—that synergistically combines these aspects of condensation and substantially outperforms other synthetic surfaces. Inspired by an unconventional interpretation of the role of the beetle’s bumpy surface geometry in promoting condensation, and using theoretical modelling, we show how to maximize vapour diffusion fluxat the apex of convex millimetric bumps by optimizing the radius of curvature and cross-sectional shape. Integrating this apex geometry with a widening slope, analogous to cactus spines, directly couples facilitated droplet growth with fast directional transport, by creating a free-energy profile that drives the droplet down the slope before its growth rate can decrease. This coupling is further enhanced by a slippery, pitcher-plant-inspired nanocoating that facilitates feedback between coalescence-driven growth and capillary-driven motion on the way down. Bumps that are rationally designed to integrate these mechanisms are able to grow and transport large droplets even against gravity and overcome the effect of an unfavourable temperature gradient. We further observe an unprecedented sixfold-higher exponent of growth rate, faster onset, higher steady-state turnover rate, and a greater volume of water collected compared to other surfaces. We envision that this fundamental understanding and rational design strategy can be

  15. Optical color image encryption based on an asymmetric cryptosystem in the Fresnel domain

    Science.gov (United States)

    Chen, Wen; Chen, Xudong

    2011-08-01

    In recent years, optical color image encryption has attracted much attention in the information security field. Some approaches, such as digital holography, have been proposed to encrypt color images, but the previously proposed methods are developed based on optical symmetric cryptographic strategies. In this paper, we apply an optical asymmetric cryptosystem for the color image encryption instead of conventional symmetric cryptosystems. A phase-truncated strategy is applied in the Fresnel domain, and multiple-wavelength and indexed image methods are further employed. The security of optical asymmetric cryptosystem is also analyzed during the decryption. Numerical results are presented to demonstrate the feasibility and effectiveness of the proposed optical asymmetric cryptosystem for color image encryption.

  16. Model-size reduction for the analysis of symmetric structures with asymmetric boundary conditions

    Science.gov (United States)

    Noor, Ahmed K.; Whitworth, Sandra L.

    1987-01-01

    A simple computational procedure is presented for reducing the size of the analysis model for a symmetric structure with asymmetric boundary conditions to that of the corresponding structure with symmetric boundary conditions. The procedure is based on approximating the asymmetric response of the structure by a linear combination of symmetric and antisymmetric global approximation vectors (or modes). The key elements of the procedure are (1) restructuring the governing finite-element equations to delineate the contributions to the symmetric and antisymmetric components of the asymmetric response, (2) successive application of the finite element method and the classical Rayleigh-Ritz technique. The finite-element method is first used to generate a few global approximation vectors (or modes). Then the amplitudes of these modes are computed by using the Rayleigh-Ritz technique. The effectiveness of the computational procedure is demonstrated by means of numerical examples of linear static problems of shells, and its potential for solving nonlinear problems is discussed.

  17. Asymmetric transmission of acoustic waves in a layer thickness distribution gradient structure using metamaterials

    Science.gov (United States)

    Chen, Jung-San; Chang, I.-Ling; Huang, Wan-Ting; Chen, Lien-Wen; Huang, Guan-Hua

    2016-09-01

    This research presents an innovative asymmetric transmission design using alternate layers of water and metamaterial with complex mass density. The directional transmission behavior of acoustic waves is observed numerically inside the composite structure with gradient layer thickness distribution and the rectifying performance of the present design is evaluated. The layer thickness distributions with arithmetic and geometric gradients are considered and the effect of gradient thickness on asymmetric wave propagation is systematically investigated using finite element simulation. The numerical results indicate that the maximum pressure density and transmission through the proposed structure are significantly influenced by the wave propagation direction over a wide range of audible frequencies. Tailoring the thickness of the layered structure enables the manipulation of asymmetric wave propagation within the desired frequency range. In conclusion, the proposed design offers a new possibility for developing directional-dependent acoustic devices.

  18. The asymmetric segregation of damaged proteins is stem cell-type dependent.

    Science.gov (United States)

    Bufalino, Mary Rose; DeVeale, Brian; van der Kooy, Derek

    2013-05-13

    Asymmetric segregation of damaged proteins (DPs) during mitosis has been linked in yeast and bacteria to the protection of one cell from aging. Recent evidence suggests that stem cells may use a similar mechanism; however, to date there is no in vivo evidence demonstrating this effect in healthy adult stem cells. We report that stem cells in larval (neuroblast) and adult (female germline and intestinal stem cell) Drosophila melanogaster asymmetrically segregate DPs, such as proteins with the difficult-to-degrade and age-associated 2,4-hydroxynonenal (HNE) modification. Surprisingly, of the cells analyzed only the intestinal stem cell protects itself by segregating HNE to differentiating progeny, whereas the neuroblast and germline stem cells retain HNE during division. This led us to suggest that chronological life span, and not cell type, determines the amount of DPs a cell receives during division. Furthermore, we reveal a role for both niche-dependent and -independent mechanisms of asymmetric DP division. PMID:23649805

  19. Localized surface plasmon resonance modes on an asymmetric cylindrical nanorod dimer

    Science.gov (United States)

    Wang, Rui-Bing; Zhang, Zhi-Dong; Jiao, Guo-Tai; Xue, Chen-Yang; Yan, Shu-Bin; Wang, Hongyang

    2016-08-01

    The extinction spectra and electric field distribution of an asymmetric cylindrical nanorod dimer (ACND) are calculated by discrete dipole approximation. The ACND is composed of two linear orders of cylindrical silver nanorods with different radii and lengths. The effects of the structural parameters of ACND on the localized surface plasmon resonance (LSPR) mode are also studied. Results show two resonance peaks in the extinction spectra of ACND: the higher-energy anti-bonding mode and the lower-energy bonding mode. The interaction of two hybridization plasmonic resonance modes produces an asymmetric line shape in the extinction spectra, which is considered to be a Fano resonance profile.

  20. Unravelling Thiol’s Role in Directing Asymmetric Growth of Au Nanorod–Au Nanoparticle Dimers

    KAUST Repository

    Huang, Jianfeng

    2015-12-15

    Asymmetric nanocrystals have practical significance in nanotechnologies but present fundamental synthetic challenges. Thiol ligands have proven effective in breaking the symmetric growth of metallic nanocrystals but their exact roles in the synthesis remain elusive. Here, we synthesized an unprecedented Au nanorod-Au nanoparticle (AuNR-AuNP) dimer structure with the assistance of a thiol ligand. On the basis of our experimental observations, we unraveled for the first time that the thiol could cause an inhomogeneous distribution of surface strains on the seed crystals as well as a modulated reduction rate of metal precursors, which jointly induced the asymmetric growth of monometallic dimers. © 2015 American Chemical Society.

  1. 中小企业互联网融资中的信息不对称、融资约束与第三方鉴证%Asymmetric Information , Financial Constraints and the Effects of Third Party Verification and Evaluation in SMEs ' Internet Financing

    Institute of Scientific and Technical Information of China (English)

    雷倩华

    2015-01-01

    SMEs pay an important role in economic growth, employment pressure, people's life and technological innovation and so on. But financing difficulties have long been bothering SMEs. The development of internet financing has reduced the financing constraints for SMEs, but the asymmetric information increases the SMEs' financing cost and financing amount. The third party verification and evaluating has not been introduced to solve the problem of asymmetric information in internet financing , and the literature has not discussed it. This paper discusses the asymmetric information situation in different internet financing, and third party verification and evaluation's effects on reducing asymmetric information. Finally , this paper proposes some related policies in establishing third party verification and evaluation system.%中小企业在保证我国经济适度增长、缓解就业压力、方便群众生活和推动技术创新等方面发挥着重要的作用,但融资难问题长期困扰着中小企业.互联网融资的发展减轻了中小企业的融资约束,但互联网融资中的信息不对称增加了中小企业的融资成本和融资额度.互联网融资实践中还没有引入第三方鉴证与评估来解决信息不对称问题,已有文献也并未对此进行探讨.本文阐述了不同的互联网融资模式中存在的信息不对称的状况和第三方鉴证与评估在减轻不同的互联网融资模式中的信息不对称的作用.最后,本文提出了在我国建立第三方鉴证与评估体系的相关建议.

  2. 我国货币政策信贷传导渠道的非对称效应及地区经济影响%Asymmetric Effect of Credit Transmission Channel of Monetary Policy in China and Its Regional Economic Effects

    Institute of Scientific and Technical Information of China (English)

    陆虹

    2012-01-01

    This paper employs STR model and LM statistic test to make an empirical study of the asymmetric effect of credit transmission channel of monetary policy and its regional economic effects based on relevant quarter data from 1996 to 2012. The results show that the effect of credit transmis sion channel of monetary policy in China is obviously featured by asymme try, namely strong nonlinearity, and this asymmetry has different effects on economic operation in the whole nation and eastern, central and western re gions.%文章以1996-2012年的相关季度统计数据,运用STR模型和LM统计检验方法,对我国货币政策信贷传导渠道的非对称效应及地区经济影响进行了实证研究。结果显示,我国货币政策信贷传导渠道效果存在明显的不对称特性,即具有很强的非线性特征;同时,这种不对称性对我国及东中西部地区的经济运行存在不同的影响。

  3. Tunable magnetoresistance in an asymmetrically coupled single-molecule junction

    Science.gov (United States)

    Warner, Ben; El Hallak, Fadi; Prüser, Henning; Sharp, John; Persson, Mats; Fisher, Andrew J.; Hirjibehedin, Cyrus F.

    2015-03-01

    Phenomena that are highly sensitive to magnetic fields can be exploited in sensors and non-volatile memories. The scaling of such phenomena down to the single-molecule level may enable novel spintronic devices. Here, we report magnetoresistance in a single-molecule junction arising from negative differential resistance that shifts in a magnetic field at a rate two orders of magnitude larger than Zeeman shifts. This sensitivity to the magnetic field produces two voltage-tunable forms of magnetoresistance, which can be selected via the applied bias. The negative differential resistance is caused by transient charging of an iron phthalocyanine (FePc) molecule on a single layer of copper nitride (Cu2N) on a Cu(001) surface, and occurs at voltages corresponding to the alignment of sharp resonances in the filled and empty molecular states with the Cu(001) Fermi energy. An asymmetric voltage-divider effect enhances the apparent voltage shift of the negative differential resistance with magnetic field, which inherently is on the scale of the Zeeman energy. These results illustrate the impact that asymmetric coupling to metallic electrodes can have on transport through molecules, and highlight how this coupling can be used to develop molecular spintronic applications.

  4. Asymmetric gold nanoparticle reduction into polydimethylsiloxane thin films

    Science.gov (United States)

    Dunklin, Jeremy R.; Forcherio, Gregory T.; Berry, Keith R.; Roper, D. Keith

    2014-09-01

    Polymer thin films embedded with plasmonic gold nanoparticles (AuNPs) are of significant interest in biomedicine, optics, photovoltaic, and nanoelectromechanical systems. Thin polydimethylsiloxane (PDMS) films containing 3-7 micron layers of AuNPs that were fabricated with a novel diffusive-reduction synthesis technique attenuated up to 85% of incoming laser light at the plasmon resonance. Rapid diffusive reduction of AuNPs into asymmetric PDMS thin films provided superior optothermal capabilities relative to thicker films in which AuNPs were reduced throughout. A photonto- heat conversion of up to 3000°C/watt was demonstrated, which represents a 3-230-fold increase over previous AuNPfunctionalized systems. Optical attenuation and thermal response increased in proportion to order of magnitude increases in tetrachloroaurate (TCA) solution concentration. Optical and thermoplasmonic responses were observed with and without an adjacent mesh support, which increased attenuation but decreased thermal response. Morphological, optical, and thermoplasmonic properties of asymmetric AuNP-PDMS films varied significantly with diffusive TCA concentration. Gold nanoparticles, networks, and conglomerates were formed via reduction as the amount of dissolved TCA increased across a log10-scale. Increasing TCA concentrations caused polymer surface cratering, leading to a larger effective surface area. This method, utilizing the diffusion of TCA into a single exposed partially cured PDMS interface, could be used to replace expensive lithographic or solution synthesis of plasmon-functionalized systems.

  5. Asymmetric-shell ignition capsule design to tune the low-mode asymmetry during the peak drive

    Science.gov (United States)

    Gu, Jianfa; Dai, Zhensheng; Song, Peng; Zou, Shiyang; Ye, Wenhua; Zheng, Wudi; Gu, Peijun; Wang, Jianguo; Zhu, Shaoping

    2016-08-01

    The low-mode radiation flux asymmetry in the hohlraum is a main source of performance degradation in the National Ignition Facility (NIF) implosion experiments. To counteract the deleterious effects of the large positive P2 flux asymmetry during the peak drive, this paper develops a new tuning method called asymmetric-shell ignition capsule design which adopts the intentionally asymmetric CH ablator layer or deuterium-tritium (DT) ice layer. A series of two-dimensional implosion simulations have been performed, and the results show that the intentionally asymmetric DT ice layer can significantly improve the fuel ρR symmetry, hot spot shape, hot spot internal energy, and the final neutron yield compared to the spherical capsule. This indicates that the DT asymmetric-shell capsule design is an effective tuning method, while the CH ablator asymmetric-shell capsule could not correct the fuel ρR asymmetry, and it is not as effective as the DT asymmetric-shell capsule design.

  6. Biased transportations in a spatially asymmetric system at the nano-scale under thermal noise

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Under the theory of ratchet effect for mesoand macro-scale systems, the additional perturbation with a long time correlation and the breaking of spatial inversion symmetry are two main ingredients to bring unidirected transportations. With the help of a simple model system, we show that a spatially asymmetric system of the nano-scale length may induce biased transportations under thermal noise.

  7. A numerical strategy for finite element modeling of frictionless asymmetric vocal fold collision

    DEFF Research Database (Denmark)

    Granados, Alba; Misztal, Marek Krzysztof; Brunskog, Jonas;

    2016-01-01

    . Theoretical background and numerical analysis of the finite-element position-based contact model are presented, along with validation. A novel contact detection mechanism capable to detect collision in asymmetric oscillations is developed. The effect of inexact contact constraint enforcement on vocal fold...

  8. Consequences of DM/antiDM oscillations for asymmetric WIMP darkmatter

    DEFF Research Database (Denmark)

    Cirelli, M.; Panci, P.; Servant, G.;

    2012-01-01

    Assuming the existence of a primordial asymmetry in the dark sector, a scenario usually dubbed Asymmetric Dark Matter (aDM), we study the effect of oscillations between dark matter and its antiparticle on the re-equilibration of the initial asymmetry before freeze-out, which enable efficient anni...

  9. Asymmetric-Structure Analysis of Carbon and Energy Markets

    Science.gov (United States)

    Xu, Wei; Cao, Guangxi

    2016-02-01

    This study aimed to investigate the asymmetric structure between the carbon and energy markets from two aspects of different trends (up or down) and volatility-transmission direction using asymmetric detrended cross-correlation analysis (DCCA) cross-correlation coefficient test, multifractal asymmetric DCCA (MF-ADCCA) method, asymmetric volatility-constrained correlation metric and time rate of information-flow approach. We sampled 1283 observations from January 2008 to December 2012 among pairs of carbon and energy markets for analysis. Empirical results show that the (1) asymmetric characteristic from the cross-correlation between carbon and returns in the energy markets is significant, (2) asymmetric cross-correlation between carbon and energy market price returns is persistent and multifractral and (3) volatility of the base assets of energy market returns is more influential to the base asset of the carbon market than that of the energy market.

  10. Asymmetric Synthesis of Both Enantiomers of Disparlure

    Institute of Scientific and Technical Information of China (English)

    王志刚; 郑剑峰; 黄培强

    2012-01-01

    Starting from propargyl alcohol (12), and on the basis of Zhou's modified Sharpless asymmetric epoxidation, the sex pheromone of the Gypsy moth, disparlure (+)-8 and its enantiomer (-)-8 have been synthesized, each in six steps, with overall yields of 29% for (+)-8 and 27% for (-)-8 (ee〉98%). The use of the sequential coupling tactic renders the method flexible, which is applicable to the synthesis of other cis-epoxy pheromones.

  11. Infinite dimensional mixed economies with asymmetric information

    CERN Document Server

    Bhowmik, Anuj

    2011-01-01

    In this paper, we study asymmetric information economies consisting of both non-negligible and negligible agents and having ordered Banach spaces as their commodity spaces. In answering a question of Herv\\'{e}s-Beloso and Moreno-Garc\\'{i}a, we establish a characterization of Walrasian expectations allocations by the veto power of the grand coalition. It is also shown that when an economy contains only negligible agents a Vind's type theorem on the private core with the exact feasibility can be restored. This solves a problem of Pesce.

  12. Quantum optics of lossy asymmetric beam splitters

    CERN Document Server

    Uppu, Ravitej; Tentrup, Tristan B H; Pinkse, Pepijn W H

    2016-01-01

    We theoretically investigate quantum interference of two single photons at a lossy asymmetric beam splitter, the most general passive 2$\\times$2 optical circuit. The losses in the circuit result in a non-unitary scattering matrix with a non-trivial set of constraints on the elements of the scattering matrix. Our analysis using the noise operator formalism shows that the loss allows tunability of quantum interference to an extent not possible with a lossless beam splitter. Our theoretical studies support the experimental demonstrations of programmable quantum interference in highly multimodal systems such as opaque scattering media and multimode fibers.

  13. On asymmetric causal relationships in Petropolitics

    Directory of Open Access Journals (Sweden)

    Balan Feyza

    2016-01-01

    Full Text Available The aim of this paper is to examine whether the First Law of Petropolitics denominated by Friedman in 2006 is valid for OPEC countries. To do this, this paper analyses the relationship between political risk and oil supply by applying the asymmetric panel causality test suggested by Hatemi-J (2011 to these countries for the period 1984-2014. The results show that the First Law of Petropolitics is valid for Angola, Iraq, Kuwait, Libya, Nigeria, Qatar, Saudi Arabia, and the UAE, given that positive oil supply shocks significantly lead to negative political stability shocks, and negative oil supply shocks significantly lead to positive shocks in political stability.

  14. OFFICER AND COMMANDER IN ASYMMETRIC WARFARE OPERATIONS

    Directory of Open Access Journals (Sweden)

    Giuseppe CAFORIO

    2013-01-01

    Full Text Available Starting from the data of a field research conducted among soldiers with asymmetric warfare experiences from nine different countries, the author seeks to identify and shed light on the various problems that officers with command responsibilities had to face during their missions. A picture emerges of feelings and experiences relating to their first impression upon arriving in the theatre, relations with local armed forces, relations with the local population and local authorities, relations with NGOs, relations with other armies, the impact of the rules of engagement (ROEs, training and education, and operational experiences. The paper ends with a discussion of the lessons learned.

  15. Asymmetric Hydrogenation of 3-Substituted Pyridinium Salts.

    Science.gov (United States)

    Renom-Carrasco, Marc; Gajewski, Piotr; Pignataro, Luca; de Vries, Johannes G; Piarulli, Umberto; Gennari, Cesare; Lefort, Laurent

    2016-07-01

    The use of an equivalent amount of an organic base leads to high enantiomeric excess in the asymmetric hydrogenation of N-benzylated 3-substituted pyridinium salts into the corresponding piperidines. Indeed, in the presence of Et3 N, a Rh-JosiPhos catalyst reduced a range of pyridinium salts with ee values up to 90 %. The role of the base was elucidated with a mechanistic study involving the isolation of the various reaction intermediates and isotopic labeling experiments. Additionally, this study provided some evidence for an enantiodetermining step involving a dihydropyridine intermediate. PMID:27140832

  16. Quantum optics of lossy asymmetric beam splitters

    Science.gov (United States)

    Uppu, Ravitej; Wolterink, Tom A. W.; Tentrup, Tristan B. H.; Pinkse, Pepijn W. H.

    2016-07-01

    We theoretically investigate quantum interference of two single photons at a lossy asymmetric beam splitter, the most general passive 2$\\times$2 optical circuit. The losses in the circuit result in a non-unitary scattering matrix with a non-trivial set of constraints on the elements of the scattering matrix. Our analysis using the noise operator formalism shows that the loss allows tunability of quantum interference to an extent not possible with a lossless beam splitter. Our theoretical studies support the experimental demonstrations of programmable quantum interference in highly multimodal systems such as opaque scattering media and multimode fibers.

  17. Plasma current resonance in asymmetric toroidal systems

    Energy Technology Data Exchange (ETDEWEB)

    Hazeltine, R. D. [Institute for Fusion Studies, University of Texas at Austin, Austin, Texas 78712 (United States); Catto, Peter J. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, 167 Albany Street, Cambridge, Massachusetts 02139 (United States)

    2015-09-15

    The well-known singularity in the magnetic differential equation for plasma current in an asymmetric toroidal confinement system is resolved by including in the pressure tensor corrections stemming from finite Larmor radius. The result provides an estimate of the amplitude of spikes in the parallel current that occur on rational magnetic surfaces. Resolution of the singularity is shown to depend on both the ambipolarity condition—the requirement of zero surface-averaged radial current—and the form of the magnetic differential equation near the rational surface.

  18. Plasmonic photodetectors based on asymmetric nanogap electrodes

    Science.gov (United States)

    Ge, Junyu; Luo, Manlin; Zou, Wanghui; Peng, Wei; Duan, Huigao

    2016-08-01

    Hot electrons excited by plasmon resonance in nanostructure can be employed to enhance the properties of photodetectors, even when the photon energy is lower than the bandgap of the semiconductor. However, current research has seldom considered how to realize the efficient collection of hot electrons, which restricts the responsivity of the device. In this paper, a type of plasmonic photodetector based on asymmetric nanogap electrodes is proposed. Owing to this structure, the device achieves responsivities as high as 0.45 and 0.25 mA/W for wavelengths of 1310 and 1550 nm, respectively. These insights can aid the realization of efficient plasmon-enhanced photodetectors for infrared detection.

  19. Nanotribology of Symmetric and Asymmetric Liquid Lubricants

    Directory of Open Access Journals (Sweden)

    Shinji Yamada

    2010-03-01

    Full Text Available When liquid molecules are confined in a narrow gap between smooth surfaces, their dynamic properties are completely different from those of the bulk. The molecular motions are highly restricted and the system exhibits solid-like responses when sheared slowly. This solidification behavior is very dependent on the molecular geometry (shape of liquids because the solidification is induced by the packing of molecules into ordered structures in confinement. This paper reviews the measurements of confined structures and friction of symmetric and asymmetric liquid lubricants using the surface forces apparatus. The results show subtle and complex friction mechanisms at the molecular scale.

  20. Security-Preserving Asymmetric Protocol Encapsulation

    OpenAIRE

    Vaudenay, Serge; Phan, Raphael C-W

    2007-01-01

    Query-response based protocols between a client and a server such as SSL, TLS, SSH are asymmetric in the sense that the querying client and the responding server play different roles, and for which there is a need for two-way linkability between queries and responses within the protocol. We are motivated by the observation that though results exist in other related contexts, no provably secure scheme has been applied to the setting of client-server protocols, which differ from conventional co...

  1. Analysis of Asymmetric Piezoelectric Composite Beam

    CERN Document Server

    Chen, J -S; Wu, K -C

    2008-01-01

    This paper deals with the vibration analysis of an asymmetric composite beam composed of glass a piezoelectric material. The Bernoulli's beam theory is adopted for mechanical deformations, and the electric potential field of the piezoelectric material is assumed such that the divergence-free requirement of the electrical displacements is satisfied. The accuracy of the analytic model is assessed by comparing the resonance frequencies obtained by the analytic model with those obtained by the finite element method. The model developed can be used as a tool for designing piezoelectric actuators such as micro-pumps.

  2. Chiral Diamine-catalyzed Asymmetric Aldol Reaction

    Institute of Scientific and Technical Information of China (English)

    LI Hui; XU Da-zhen; WU Lu-lu; WANG Yong-mei

    2012-01-01

    A highly efficient catalytic system composed of a simple and commercially available chiral primary diamine (1R,2R)-cyclohexane-1,2-diamine(6) and trifluoroacetic acid(TFA) was employed for asymmetric Aldol reaction in i-PrOH at room temperature.A loading of 10%(molar fraction) catalyst 6 with TFA as a cocatalyst could catalyze the Aldol reactions of various ketones or aldehydes with a series of aromatic aldehydes,furnishing Aldol products in moderate to high yields(up to >99%) with enantioselectivities of up to >99% and diastereoselectivities of up to 99:1.

  3. Quantum optics of lossy asymmetric beam splitters.

    Science.gov (United States)

    Uppu, Ravitej; Wolterink, Tom A W; Tentrup, Tristan B H; Pinkse, Pepijn W H

    2016-07-25

    We theoretically investigate quantum interference of two single photons at a lossy asymmetric beam splitter, the most general passive 2×2 optical circuit. The losses in the circuit result in a non-unitary scattering matrix with a non-trivial set of constraints on the elements of the scattering matrix. Our analysis using the noise operator formalism shows that the loss allows tunability of quantum interference to an extent not possible with a lossless beam splitter. Our theoretical studies support the experimental demonstrations of programmable quantum interference in highly multimodal systems such as opaque scattering media and multimode fibers. PMID:27464096

  4. Long-lived oscillons from asymmetric bubbles

    CERN Document Server

    Adib, A B; Almeida, C A S; Adib, Artur B.; Gleiser, Marcelo; Almeida, Carlos A. S.

    2002-01-01

    The possibility that extremely long-lived, time-dependent, and localized field configurations (``oscillons'') arise during the collapse of asymmetrical bubbles in 2+1 dimensional \\phi^4 models is investigated. It is found that oscillons can develop from a large spectrum of elliptically deformed bubbles. Moreover, it is found that such oscillons are: a) circularly symmetric; and b) stable against small arbitrary radial and angular perturbations. They may thus play an important role in the study of time-dependent nonperturbative configurations in field theory, with applications ranging from nonequilibrium statistical physics to early universe cosmology.

  5. Neuronal Alignment On Asymmetric Textured Surfaces

    CERN Document Server

    Beighley, Ross; Sekeroglu, Koray; Atherton, Timothy; Demirel, Melik C; Staii, Cristian

    2013-01-01

    Axonal growth and the formation of synaptic connections are key steps in the development of the nervous system. Here we present experimental and theoretical results on axonal growth and interconnectivity in order to elucidate some of the basic rules that neuronal cells use for functional connections with one another. We demonstrate that a unidirectional nanotextured surface can bias axonal growth. We perform a systematic investigation of neuronal processes on asymmetric surfaces and quantify the role that biomechanical surface cues play in neuronal growth. These results represent an important step towards engineering directed axonal growth for neuro-regeneration studies.

  6. Power spectra of a constrained totally asymmetric simple exclusion process

    Science.gov (United States)

    Cook, L. Jonathan; Zia, R. K. P.

    2010-07-01

    In nature, all biological systems function in a far-from-equilibrium state. Here, we study the process of translation in protein synthesis, using the totally asymmetric simple exclusion process (TASEP) as a model. In particular, we explore the effects of a finite supply of particles for the TASEP, as in a living cell with a finite pool of ribosomes. Specifically, we investigate the power spectrum associated with total occupancy, utilizing both Monte Carlo simulations and theoretical analysis. New features arise, such as large suppressions at low frequencies, due to the added constraint. A theory is formulated based on a Langevin approach with discrete space and time. With good agreement between the simulation and theory, we gain some insights into the effects of finite resources on the TASEP.

  7. Einstein-Maxwell equations for asymmetric resonant cavities

    CERN Document Server

    Frasca, Marco

    2015-01-01

    We analyze the behavior of electromagnetic fields inside a resonant cavity by solving Einstein--Maxwell field equations. It is shown that the modified geometry of space-time inside the cavity due to a propagating mode can affect the propagation of a laser beam. It is seen that components of laser light with a shifted frequency appear originating from the coupling between the laser field and the mode cavity due to gravity. The analysis is extended to the case of an asymmetric resonant cavity taken to be a truncated cone. It is shown that a proper choice of the geometrical parameters of the cavity and dielectric can make the gravitational effects significant for an interferometric setup. This could make possible to realize table-top experiments involving gravitational effects.

  8. Collective plasmon modes in a compositionally asymmetric nanoparticle dimer

    Directory of Open Access Journals (Sweden)

    Fuyi Chen

    2011-09-01

    Full Text Available The plasmon coupling phenomenon of heterodimers composed of silver, gold and copper nanoparticles of 60 nm in size and spherical in shape were studied theoretically within the scattered field formulation framework. In-phase dipole coupled σ-modes were observed for the Ag-Au and Ag-Cu heterodimers, and an antiphase dipole coupled π-mode was observed for the Ag-Au heterodimer. These observations agree well with the plasmon hybridization theory. However, quadrupole coupled modes dominate the high energy wavelength range from 357-443 nm in the scattering cross section of the D=60 nm Ag-Au and Ag-Cu heterodimer. We demonstrate for the first time that collective plasmon modes in a compositionally asymmetric nanoparticle dimer have to be predicted from the dipole-dipole approximation of plasmon hybridization theory together with the interband transition effect of the constitutive metals and the retardation effect of the nanoparticle size.

  9. RELATIONSHIP OF TRANSVERSAL ASYMMETRIC FACE AND UNILATERAL POSTERIOR CROSSBITE

    OpenAIRE

    Indah Dwinursanty; Krisnawati Krisnawati; Maria Purbiati

    2006-01-01

    Unilateral posterior crossbite is commonly seen in mixed dentition, but it couldn’t be self corrected. If this condition is not treated properly, it could lead to asymmetric face. Asymmetric face with unilateral posterior crossbite could make the treatment process more difficult. The objective of this study is to find out the relationship between transversal skeletal asymmetry and unilateral posterior crossbite. Patients older than 13 years with skeletal asymmetric face, who had never undergo...

  10. Quantity Discount Scheme in Supply Chain under Asymmetric Information

    Institute of Scientific and Technical Information of China (English)

    LI Ji-bin; PENG Zuo-he

    2007-01-01

    Quantity discount scheme plays an important role in supply chain management. The different quantity discount schemes under symmetric (full) information and asymmetric information, are analyzed by using principal-agent and optimal control theory. As a result, the research reveals that the optimal quantity discount solution under symmetric information is a special case of that under asymmetric information. At the same price, the critical value of quantity discount under asymmetric information is much lower than that under asymmetric information. Therefore, this leads to less cost for retailers and smaller profit for their supplier.

  11. Asymmetric and axisymmetric dynamics of tropical cyclones

    Science.gov (United States)

    Persing, J.; Montgomery, M. T.; McWilliams, J. C.; Smith, R. K.

    2013-12-01

    We present the results of idealized numerical experiments to examine the difference between tropical cyclone evolution in three-dimensional (3-D) and axisymmetric (AX) model configurations. We focus on the prototype problem for intensification, which considers the evolution of an initially unsaturated AX vortex in gradient-wind balance on an f plane. Consistent with findings of previous work, the mature intensity in the 3-D model is reduced relative to that in the AX model. In contrast with previous interpretations invoking barotropic instability and related horizontal mixing processes as a mechanism detrimental to the spin-up process, the results indicate that 3-D eddy processes associated with vortical plume structures can assist the intensification process by contributing to a radial contraction of the maximum tangential velocity and to a vertical extension of tangential winds through the depth of the troposphere. These plumes contribute significantly also to the azimuthally averaged heating rate and the corresponding azimuthal-mean overturning circulation. The comparisons show that the resolved 3-D eddy momentum fluxes above the boundary layer exhibit counter-gradient characteristics during a key spin-up period, and more generally are not solely diffusive. The effects of these eddies are thus not properly represented by the subgrid-scale parameterizations in the AX configuration. The resolved eddy fluxes act to support the contraction and intensification of the maximum tangential winds. The comparisons indicate fundamental differences between convective organization in the 3-D and AX configurations for meteorologically relevant forecast timescales. While the radial and vertical gradients of the system-scale angular rotation provide a hostile environment for deep convection in the 3-D model, with a corresponding tendency to strain the convective elements in the tangential direction, deep convection in the AX model does not suffer this tendency. Also, since

  12. Particle identification at an asymmetric B Factory

    International Nuclear Information System (INIS)

    Particle identification systems are an important component of any detector at a high-luminosity, asymmetric B Factory. In particular, excellent hadron identification is required to probe CP violation in B0 decays to CP eigenstates. The particle identification systems discussed below also provide help in separating leptons from hadrons at low momenta. We begin this chapter with a discussion of the physics motivation for providing particle identification, the inherent limitations due to interactions and decays in flight, and the requirements for hermiticity and angular coverage. A special feature of an asymmetric B Factory is the resulting asymmetry in the momentum distribution as a function of polar angle; this will also be quantified and discussed. In the next section the three primary candidates, time-of-flight (TOF), energy loss (dE/dx), and Cerenkov counters, both ring-imaging and threshold, will be briefly described and evaluated. Following this, one of the candidates, a long-drift Cerenkov ring-imaging device, is described in detail to provide a reference design. Design considerations for a fast RICH are then described. A detailed discussion of aerogel threshold counter designs and associated R ampersand D conclude the chapter. 56 refs., 64 figs., 13 tabs

  13. An asymmetric B factory based on PEP

    Energy Technology Data Exchange (ETDEWEB)

    1991-02-01

    In this report we describe a design for a high-luminosity Asymmetric B Factory to be built in the PEP tunnel on the SLAC site. This proposal, a collaborative effort SLAC, LBL, and LLNL, is the culmination of more than two years of effort aimed at the design and construction of an asymmetric e{sup +}e{sup {minus}} collider capable of achieving a luminosity of L = 3 {times} 10{sup 33} cm{sup {minus}2} s{sup {minus}1}. The configuration adopted utilizes two storage rings, and electron ring operating at 9 GeV and a positron ring at 3.1 GeV, each with a circumference of 2200 m. The high-energy ring is an upgrade of the PEP storage ring at SLAC; all PEP magnets and most power supplies will be reused. The upgrade consists primarily of replacing the PEP vacuum chamber and RF system with newly designed versions optimized for the high-current environment of the B Factory. The low-energy ring will be newly constructed and will be situated atop the high-energy ring in the PEP tunnel. Utilities already installed in the PEP tunnel are largely sufficient to operate the two B Factory storage rings.

  14. Asymmetric Twin Representation: the Transfer Matrix Symmetry

    Directory of Open Access Journals (Sweden)

    Anastasia Doikou

    2007-01-01

    Full Text Available The symmetry of the Hamiltonian describing the asymmetric twin model was partially studied in earlier works, and our aim here is to generalize these results for the open transfer matrix. In this spirit we first prove, that the so called boundary quantum algebra provides a symmetry for any generic - independent of the choice of model - open transfer matrix with a trivial left boundary. In addition it is shown that the boundary quantum algebra is the centralizer of the $B$ type Hecke algebra. We then focus on the asymmetric twin representation of the boundary Temperley-Lieb algebra. More precisely, by exploiting exchange relations dictated by the reflection equation we show that the transfer matrix with trivial boundary conditions enjoys the recognized $U_q(sl_2otimes U_i(sl_2$ symmetry. When a non-diagonal boundary is implemented the symmetry as expected is reduced, however again certain familiar boundary non-local charges turn out to commute with the corresponding transfer matrix.

  15. Asymmetric disassembly and robustness in declining networks.

    Science.gov (United States)

    Saavedra, Serguei; Reed-Tsochas, Felix; Uzzi, Brian

    2008-10-28

    Mechanisms that enable declining networks to avert structural collapse and performance degradation are not well understood. This knowledge gap reflects a shortage of data on declining networks and an emphasis on models of network growth. Analyzing >700,000 transactions between firms in the New York garment industry over 19 years, we tracked this network's decline and measured how its topology and global performance evolved. We find that favoring asymmetric (disassortative) links is key to preserving the topology and functionality of the declining network. Based on our findings, we tested a model of network decline that combines an asymmetric disassembly process for contraction with a preferential attachment process for regrowth. Our simulation results indicate that the model can explain robustness under decline even if the total population of nodes contracts by more than an order of magnitude, in line with our observations for the empirical network. These findings suggest that disassembly mechanisms are not simply assembly mechanisms in reverse and that our model is relevant to understanding the process of decline and collapse in a broad range of biological, technological, and financial networks.

  16. Instability of asymmetric continuous shaft system

    Science.gov (United States)

    Srinath, R.; Sarkar, Abhijit; Sekhar, A. S.

    2016-11-01

    In this work, the governing equation of asymmetric continuous shaft in inertial frame of reference is studied. In particular, determination of the parameter ranges for the stability or instability of the shaft response is the focus of the present work. The governing equations are a fourth-order coupled partial differential equations containing time dependent coefficients. The equations are non-dimensionalized in terms of two parameters related to the average moment of inertia and the difference of moments of inertia about the principal axes. Using the latter as the asymptotic parameter and employing modal superposition, a formal methodology based on perturbation methods is developed to ascertain the stability and instability characteristics. The methodology is applicable to shafts subjected to some of the classical boundary conditions viz. simply supported, cantilever, and fixed-fixed. Similar stability curves are obtained for each mode for these different boundary conditions. The novel non-dimensionalization scheme chosen leads to the stability boundaries as well as the loci of varying speeds to be in the form of straight lines. The intersection of these lines determine the stable and unstable speed ranges of different asymmetric shafts. The results are generalized for different material and geometric properties of the shaft.

  17. An asymmetric B factory based on PEP

    International Nuclear Information System (INIS)

    In this report we describe a design for a high-luminosity Asymmetric B Factory to be built in the PEP tunnel on the SLAC site. This proposal, a collaborative effort SLAC, LBL, and LLNL, is the culmination of more than two years of effort aimed at the design and construction of an asymmetric e+e- collider capable of achieving a luminosity of L = 3 x 1033 cm-2 s-1. The configuration adopted utilizes two storage rings, and electron ring operating at 9 GeV and a positron ring at 3.1 GeV, each with a circumference of 2200 m. The high-energy ring is an upgrade of the PEP storage ring at SLAC; all PEP magnets and most power supplies will be reused. The upgrade consists primarily of replacing the PEP vacuum chamber and RF system with newly designed versions optimized for the high-current environment of the B Factory. The low-energy ring will be newly constructed and will be situated atop the high-energy ring in the PEP tunnel. Utilities already installed in the PEP tunnel are largely sufficient to operate the two B Factory storage rings

  18. Asymmetric transition disks: Vorticity or eccentricity?

    CERN Document Server

    Zsom, A; Ghanbari, J

    2013-01-01

    Context. Transition disks typically appear in resolved millimeter observations as giant dust rings surrounding their young host stars. More accurate observations with ALMA have shown several of these rings to be in fact asymmetric: they have lopsided shapes. It has been speculated that these rings act as dust traps, which would make them important laboratories for studying planet formation. It has been shown that an elongated giant vortex produced in a disk with a strong viscosity jump strikingly resembles the observed asymmetric rings. Aims. We aim to study a similar behavior for a disk in which a giant planet is embedded. However, a giant planet can induce two kinds of asymmetries: (1) a giant vortex, and (2) an eccentric disk. We studied under which conditions each of these can appear, and how one can observationally distinguish between them. This is important because only a vortex can trap particles both radially and azimuthally, while the eccentric ring can only trap particles in radial direction. Method...

  19. Asymmetric EPR entanglement in continuous variable systems

    International Nuclear Information System (INIS)

    Continuous variable entanglement can be produced in nonlinear systems or via the interference of squeezed states. In many optical systems such as parametric down conversion, the production of two perfectly symmetric subsystems is usually assumed when demonstrating the existence of entanglement. This symmetry simplifies the description of entanglement. However, asymmetry in entanglement may arise naturally in a real experiment, or be intentionally introduced in a given quantum information protocol. These asymmetries can emerge from having the output beams experience different losses and environmental contamination, or from the availability of non-identical input quantum states in quantum communication protocols. In this paper, we present a visualization of entanglement using quadrature amplitude plots of the twin beams. We quantitatively discuss the strength of asymmetric entanglement using EPR and inseparability criteria and theoretically show that the optimal beamsplitter ratio for entanglement is dependent on the asymmetries and may not be 50 : 50. To support this theory, we present experimental results showing one particular asymmetric entanglement where a 78 : 22 beamsplitter is optimal for observing entanglement. (paper)

  20. Evaluation of an Asymmetric Bistable System for Signal Detection under LévyStable Noise

    Institute of Scientific and Technical Information of China (English)

    HUANG Jia-Min; TAO Wei-Ming; XU Bo-Hou

    2012-01-01

    We evaluate the performance of a typical asymmetric bistable system for detecting aperiodic signal under Lévy stable noise.A Grünwald-Letnikov implicit finite difference method is employed to solve the fractional FokkerPlanck equation numerically.The noise-induced stochastic resonance (SR) and the parameter-induced SR both exist in the asymmetric bistable systems.The increase of the skewness parameter γ may deteriorate the system performance.However,by tuning the system parameters,the effects of asymmetry on the system performance can be reduced.%We evaluate the performance of a typical asymmetric bistable system for detecting aperiodic signal under Levy stable noise. A Griinwald-Letnikov implicit finite difference method is employed to solve the fractional Fokker-Planck equation numerically. The noise-induced stochastic resonance (SR) and the parameter-induced SR both exist in the asymmetric bistable systems. The increase of the skewness parameter 7 may deteriorate the system performance. However, by tuning the system parameters, the effects of asymmetry on the system performance can be reduced.

  1. An Asymmetric Hysteresis Model and Parameter Identification Method for Piezoelectric Actuator

    Directory of Open Access Journals (Sweden)

    Haichen Qin

    2014-01-01

    Full Text Available Hysteresis behaviour degrades the positioning accuracy of PZT actuator for ultrahigh-precision positioning applications. In this paper, a corrected hysteresis model based on Bouc-Wen model for modelling the asymmetric hysteresis behaviour of PZT actuator is established by introducing an input bias φ and an asymmetric factor ΔΦ into the standard Bouc-Wen hysteresis model. A modified particle swarm optimization (MPSO algorithm is established and realized to identify and optimize the model parameters. Feasibility and effectiveness of MPSO are proved by experiment and numerical simulation. The research results show that the corrected hysteresis model can represent the asymmetric hysteresis behaviour of the PZT actuator more accurately than the noncorrected hysteresis model based on the Bouc-Wen model. The MPSO parameter identification method can effectively identify the parameters of the corrected and noncorrected hysteresis models. Some cases demonstrate the corrected hysteresis model and the MPSO parameter identification method can be used to model smart materials and structure systems with the asymmetric hysteresis behaviour.

  2. A forecast of energy demand in Japan considering asymmetric price elasticities

    International Nuclear Information System (INIS)

    By estimating the past energy demand function by sector and types of energy in Japan, the existence of asymmetric price elasticities in most the functions was confirmed. As part of the study, a simple energy and economy model was also constructed to compare future energy demand between the cases with symmetric or asymmetric price elasticities. Results show that future energy demand with asymmetric price elasticities is greater than that with symmetric price elasticities. This result is attributed to the fact that in the asymmetric case, past maximum prices are the most significant factors and price effects will not work unless future energy prices exceed past maximum levels. One of the important implications of this study, i.e. the effect on controlling carbon dioxide emissions, is highlighted. It is pointed out that since price elasticities are small, a high rate of carbon tax is needed to decrease carbon dioxide emissions; meaning that the carbon tax should be high enough for future energy prices to exceed the historical maximum levels. The model developed in this study does not incorporate the substitution between fuels, it is, therefore, not suitable for the further quantitative analysis of the carbon tax. While the study does not deny the applicability of the econometric approach to greenhouse gas analysis, it does point to the an importance of being conscious of the limits of the econometric approach. 7 refs., 4 tabs., 3 figs, 1 appendix

  3. Underwater asymmetric acoustic transmission structure using the medium with gradient change of impedance

    Science.gov (United States)

    Bo, Hu; Jie, Shi; Sheng-Guo, Shi; Yu, Sun; Zhong-Rui, Zhu

    2016-02-01

    We propose an underwater asymmetric acoustic transmission structure comprised of two media each with a gradient change of acoustic impedance. By gradually increasing the acoustic impedances of the media, the propagating direction of the acoustic wave can be continuously bent, resulting in allowing the acoustic wave to pass through along the positive direction and blocking acoustic waves from the negative one. The main advantages of this structure are that the asymmetric transmission effect of this structure can be realized and enhanced more easily in water. We investigate both numerically and experimentally the asymmetric transmission effect. The experimental results show that a highly efficient asymmetric acoustic transmission can be yielded within a remarkable broadband frequency range, which agrees well with the numerical prediction. It is of potential practical significance for various underwater applications such as reducing vibration and noise. Project supported by the National Natural Science Foundation of China (Grant Nos. 11204049 and 11204050), the Program for Changjiang Scholars and Innovative Research Team in University of Ministry of Education of China (Grant No. IRT1228), and the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant Nos. 20122304120023 and 20122304120011).

  4. Turbulent mixed convection in asymmetrically heated vertical channel

    Directory of Open Access Journals (Sweden)

    Mokni Ameni

    2012-01-01

    Full Text Available In this paper an investigation of mixed convection from vertical heated channel is undertaken. The aim is to explore the heat transfer obtained by adding a forced flow, issued from a flat nozzle located in the entry section of a channel, to the up-going fluid along its walls. Forced and free convection are combined studied in order to increase the cooling requirements. The study deals with both symmetrically and asymmetrically heated channel. The Reynolds number based on the nozzle width and the jet velocity is assumed to be 3 103 and 2.104; whereas, the Rayleigh number based on the channel length and the wall temperature difference varies from 2.57 1010 to 5.15 1012. The heating asymmetry effect on the flow development including the mean velocity and temperature the local Nusselt number, the mass flow rate and heat transfer are examined.

  5. Cyber Defense from “Reduction in Asymmetrical Information” Strategies

    Directory of Open Access Journals (Sweden)

    Guy-Philippe Goldstein

    2013-12-01

    Full Text Available This essay confronts two main problems in cyber defense: the attribution issue (who is attacking? and the threshold issue (is it worth all-out war?. Starting with a war-game scenario, an analytical framework based on the Tallinn Manual is suggested to delineate cases for wars and areas of crises. The prosecution of cyber crises is then proposed through two “reduction in asymmetrical information” strategies. The threshold issue can be alleviated with a better understanding of observable and simulated effects on the defending networked nation modeled as a system, drawing on the initial concept proposed by Col. John Warden. The attribution issue must be solved through excellence in elucidation methods and internationally supported coercive investigation, inspired by Thomas Schelling’s compellence. The growing preeminence of the digital domain in our modern societies could make these strategies among the building blocks of a new doctrine for military and political stability in the twenty-first century.

  6. Non-geometric fluxes, asymmetric strings and nonassociative geometry

    Energy Technology Data Exchange (ETDEWEB)

    Blumenhagen, R; Deser, A; Luest, D; Rennecke, F [Max-Planck-Institut fuer Physik (Werner-Heisenberg-Institut), Foehringer Ring 6, 80805 Muenchen (Germany); Plauschinn, E, E-mail: blumenha@mpp.mpg.de, E-mail: deser@mpp.mpg.de, E-mail: luest@mpp.mpg.de, E-mail: e.plauschinn@uu.nl, E-mail: rennecke@mpp.mpg.de [Institute for Theoretical Physics and Spinoza Institute, Utrecht University, 3508 TD Utrecht (Netherlands)

    2011-09-23

    We study closed bosonic strings propagating both in a flat background with constant H-flux and in its T-dual configurations. We define a conformal field theory capturing linear effects in the flux and compute scattering amplitudes of tachyons, where the Rogers dilogarithm plays a prominent role. For the scattering of four tachyons, a fluxed version of the Virasoro-Shapiro amplitude is derived and its pole structure is analysed. In the case of an R-flux background obtained after three T-dualities, we find indications for a nonassociative target-space structure which can be described in terms of a deformed tri-product. Remarkably, this product is compatible with crossing symmetry of conformal correlation functions. We finally argue that the R-flux background flows to an asymmetric CFT. (paper)

  7. Performance-Enhancing Asymmetric Separator for Lithium-Sulfur Batteries.

    Science.gov (United States)

    Conder, Joanna; Forner-Cuenca, Antoni; Gubler, Elisabeth Müller; Gubler, Lorenz; Novák, Petr; Trabesinger, Sigita

    2016-07-27

    Asymmetric separators with polysulfide barrier properties consisting of porous polypropylene grafted with styrenesulfonate (PP-g-PLiSS) were characterized in lithium-sulfur cells to assess their practical applicability. Galvanostatic cycling at different C-rates with and without an electrolyte additive and cyclic voltammetry were used to probe the electrochemical performance of the cells with the PP-g-PLiSS separators and to compare it with the performance of the cells utilizing state-of-the-art separator, Celgard 2400. Overall, it was found that regardless of the applied cycling rate, the use of the grafted separators greatly enhances the Coulombic efficiency of the cell. An appropriate Li-exchange-site (-SO3(-)) concentration at and near the surface of the separator was found to be essential to effectively suppress the polysulfide shuttle without sacrificing the Li-ion mobility through the separator and to improve the practical specific charge of the cell. PMID:27367443

  8. Optical nonreciprocal transmission in an asymmetric silicon photonic crystal structure

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Zheng; Chen, Juguang; Ji, Mengxi; Huang, Qingzhong; Xia, Jinsong; Wang, Yi, E-mail: yingwu2@126.com, E-mail: ywangwnlo@mail.hust.edu.cn [Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); Wu, Ying, E-mail: yingwu2@126.com, E-mail: ywangwnlo@mail.hust.edu.cn [Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); School of Physics, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China)

    2015-11-30

    An optical nonreciprocal transmission (ONT) is realized by employing the nonlinear effects in a compact asymmetric direct-coupled nanocavity-waveguide silicon photonic crystal structure with a high loaded quality factor (Q{sub L}) of 42 360 and large extinction ratio exceeding 30 dB. Applying a single step lithography and successive etching, the device can realize the ONT in an individual nanocavity, alleviating the requirement to accurately control the resonance of the cavities. A maximum nonreciprocal transmission ratio of 21.1 dB as well as a working bandwidth of 280 pm in the telecommunication band are obtained at a low input power of 76.7 μW. The calculated results by employing a nonlinear coupled-mode model are in good agreement with the experiment.

  9. Quasi-Bessel beams from asymmetric and astigmatic illumination sources.

    Science.gov (United States)

    Müller, Angelina; Wapler, Matthias C; Schwarz, Ulrich T; Reisacher, Markus; Holc, Katarzyna; Ambacher, Oliver; Wallrabe, Ulrike

    2016-07-25

    We study the spatial intensity distribution and the self-reconstruction of quasi-Bessel beams produced from refractive axicon lenses with edge emitting laser diodes as asymmetric and astigmatic illumination sources. Comparing these to a symmetric mono-mode fiber source, we find that the asymmetry results in a transition of a quasi-Bessel beam into a bow-tie shaped pattern and eventually to a line shaped profile at a larger distance along the optical axis. Furthermore, we analytically estimate and discuss the effects of astigmatism, substrate modes and non-perfect axicons. We find a good agreement between experiment, simulation and analytic considerations. Results include the derivation of a maximal axicon angle related to astigmatism of the illuminating beam, impact of laser diode beam profile imperfections like substrate modes and a longitudinal oscillation of the core intensity and radius caused by a rounded axicon tip. PMID:27464190

  10. Electronic properties of asymmetrically doped twisted graphene bilayers

    Science.gov (United States)

    Trambly de Laissardière, Guy; Namarvar, Omid Faizy; Mayou, Didier; Magaud, Laurence

    2016-06-01

    Rotated graphene bilayers form an exotic class of nanomaterials with fascinating electronic properties governed by the rotation angle θ . For large rotation angles, the electron eigenstates are restricted to one layer and the bilayer behaves like two decoupled graphene layers. At intermediate angles, Dirac cones are preserved but with a lower velocity and van Hove singularities are induced at energies where the two Dirac cones intersect. At very small angles, eigenstates become localized in peculiar moiré zones. We analyze here the effect of an asymmetric doping for a series of commensurate rotated bilayers on the basis of tight-binding calculations of their band dispersions, density of states, participation ratio, and diffusive properties. While a small doping level preserves the θ dependence of the rotated bilayer electronic structure, larger doping induces a further reduction of the band velocity in the same way as a further reduction of the rotation angle.

  11. Asymmetric coherent transmission for single particle diode and gyroscope

    CERN Document Server

    Yang, S; Sun, C P

    2009-01-01

    We study the single particle scattering process in a coherent multi-site system consisting of a tight-binding ring threaded by an Aharonov-Bohm flux and several attaching leads. The asymmetric behavior of scattering matrix is discovered analytically in the framework of both Bethe Ansatz and Green's function formalism. It is found that, under certain conditions, a three-site electronic system can behave analogous to a perfect semiconductor diode where current flows only in one direction. The general result is also valid for a neutral particle system since the effective magnetic flux may be implemented by a globe rotation. This observation means that the three-site system can serve as an orientation measuring gyroscope due to the approximate linear dependence of the current difference of two output leads on the rotational angular velocity.

  12. Optical nonreciprocal transmission in an asymmetric silicon photonic crystal structure

    International Nuclear Information System (INIS)

    An optical nonreciprocal transmission (ONT) is realized by employing the nonlinear effects in a compact asymmetric direct-coupled nanocavity-waveguide silicon photonic crystal structure with a high loaded quality factor (QL) of 42 360 and large extinction ratio exceeding 30 dB. Applying a single step lithography and successive etching, the device can realize the ONT in an individual nanocavity, alleviating the requirement to accurately control the resonance of the cavities. A maximum nonreciprocal transmission ratio of 21.1 dB as well as a working bandwidth of 280 pm in the telecommunication band are obtained at a low input power of 76.7 μW. The calculated results by employing a nonlinear coupled-mode model are in good agreement with the experiment

  13. Asymmetric bilayer graphene nanoribbon MOSFETs for analog and digital electronics

    Science.gov (United States)

    Dinarvand, A.; Ahmadi, V.; Darvish, Gh.

    2016-05-01

    In this paper, a new structure was proposed for bilayer graphene nanoribbon field-effect transistor (BGNFET) mainly to enhance the electrical characteristics in analog and digital applications. The proposed device uses two metallic gates on the top and bottom of a bilayer graphene nanoribbon, which is surrounded by SiO2 and connected to heavily doped source/drain contacts. Electrical properties of the proposed device were explored using fully self-consistent solution of Poisson and Schrödinger equations based on the nonequilibrium Green's function (NEGF) formalism. Significant improvements in the electrical behavior was seen in the simulation results for gates asymmetrically biased. The comparison with graphene nanoribbon FET showed that the proposed structure benefited from higher intrinsic voltage gain and cut-off frequency and improved switching characteristics such as delay and Ion/Ioff ratio.

  14. Asymmetric Bellow Flexible Pneumatic Actuator for Miniature Robotic Soft Gripper

    Directory of Open Access Journals (Sweden)

    Ganesha Udupa

    2014-01-01

    Full Text Available The necessity of the soft gripping devices is increasing day-by-day in medical robotics especially when safe, gentle motions and soft touch are necessary. In this paper, a novel asymmetric bellow flexible pneumatic actuator (AFPA has been designed and fabricated to construct a miniaturised soft gripper that could be used to grip small objects. The model of AFPA is designed using solid works and its bending motion is simulated in Abaqus software for optimisation and compared with experimental results. The actuator is fabricated using compression molding process that includes micromachining of the molds. Experiments conducted show the bending characteristics of the actuator at different pressures. The actuator shows excellent bending performance and the eccentricity in its design supports increased bending or curling motion up to a certain extent compared to normal bellows without eccentricity. The effects of profile shape and eccentricity on the actuator performance are analysed and the results are presented.

  15. Dynamic Resource Access Using Graphical Game in Asymmetric Wireless Networks

    Directory of Open Access Journals (Sweden)

    Fangwei Li

    2013-08-01

    Full Text Available In order to improve the resource utilization in asymmetric wireless networks, a novel dynamic resource access algorithm was presented. As the asymmetry of information and the locality of users' actions in distributed wireless networks, the resource access problem was expressed as a simple graphical game model. Let the graphic topology indicate the internal game structure of the realistic environment. Then the Nash equilibrium was got by minimizing the individual regret instead of the system regret. The proposed algorithm realized efficient resource access through exchanging the active information and regret in the competitive community. Theoretical analysis and simulation results show that the algorithm can converge to a suitable pure strategy Nash equilibrium point quickly with less amount of calculation, avoids conflict effectively, and improves the system capacity and power utilization especially in the condition of insufficient resources

  16. A new convenient asymmetric approach to herbarumin Ⅲ

    Institute of Scientific and Technical Information of China (English)

    Xue Song Chen; Shi Jun Da; Li Hong Yang; Bo Yan Xu; Zhi Xiang Xie; Ying Li

    2007-01-01

    The asymmetric total synthesis of herbarumin Ⅲ 3, a naturally occurred phytotoxin, along with 8-epi-herbarumin Ⅲ 22, was succeeded in 12 steps from n-butyraldehyde based on Brown's asymmetric allylation, taking modified Julia olefination and Yamaguchi's macro-lactonization as key steps.

  17. Asymmetric Catalytic Reactions Catalyzed by Chiral Titanium Complexes

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@ Chiral titanium complexes is very importance catalyst to asymmetric catalytic reactions. A series of catalytic systems based on titanium-chiral ligands complexes has been reported. This presentation will discuss some of our recent progress on asymmetric catalytic reactions catalyzed by chiral titanium complexes.

  18. Asymmetric Catalytic Reactions Catalyzed by Chiral Titanium Complexes

    Institute of Scientific and Technical Information of China (English)

    FENG; XiaoMing

    2001-01-01

    Chiral titanium complexes is very importance catalyst to asymmetric catalytic reactions. A series of catalytic systems based on titanium-chiral ligands complexes has been reported. This presentation will discuss some of our recent progress on asymmetric catalytic reactions catalyzed by chiral titanium complexes.  ……

  19. Asymmetric catalytic synthesis of the proposed structure of trocheliophorolide B.

    Science.gov (United States)

    Trost, Barry M; Quintard, Adrien

    2012-09-01

    A concise catalytic asymmetric synthesis of the proposed structure of trocheliophorolide B is reported. The synthetic sequence notably features an asymmetric acetaldehyde alkynylation, a Ru-catalyzed alder-ene reaction, and a Zn-ProPhenol ynone aldol condensation. Comparison with the reported data suggests a misassignment of the natural product structure.

  20. Asymmetric catalytic synthesis of the proposed structure of trocheliophorolide B

    OpenAIRE

    Trost, Barry M.; Quintard, Adrien

    2012-01-01

    A concise catalytic asymmetric synthesis of the proposed structure of Trocheliophorolide B is reported. The synthetic sequence notably features an asymmetric acetaldehyde alkynylation, Ru-catalyzed alder-ene reaction and Zn-ProPhenol ynone aldol condensation. Comparison with the reported data suggests a miss-assignment of the natural product structure.

  1. ASYMMETRIC HYDROSILYLATION CATALYZED BY POLYMER—SUPPORTED THIAZOLIDINE RHODIUM CATALYSTS

    Institute of Scientific and Technical Information of China (English)

    LEIYanohui; LIHong; 等

    1999-01-01

    Asymmetric hydrisilylation catalyzed by polymeric thiazolidine rhodium catalysts was conducted.Almost the same optical yields have been obtained when comb-shaped polymeric ligands and their corresponding monomer complexed rhodium cataltysts were used to asymmetric hydrosilylation of acetophenone.Optical yield of chiral 1-methylbenzyl alcohol reaches as high as 71.5%.Temperature dependence of enantioselective hydrosilylation of acetophenone was discussed.

  2. Extensive Taguchi's Quality Loss Function Based On Asymmetric tolerances

    Institute of Scientific and Technical Information of China (English)

    ZHU Wei; LI Yuan-sheng; LIU Feng

    2004-01-01

    If specification interval is asymmetric, basic specification is the target value of quality characteristics. In this paper Taguchi's quality loss function is applied to describe quality loss based on asymmetric tolerances. The measurement of quality loss which is caused by the deviation of quality characteristics from basic specification is further presented.

  3. Asymmetric group loans, non-assortative matching and adverse selection

    NARCIS (Netherlands)

    Gangopadhyay, Shubhashis; Lensink, Robert

    2014-01-01

    This paper shows that an asymmetric group debt contract, where one borrower co-signs for another, but not vice versa, leads to heterogeneous matching. The analysis suggests that micro finance organizations can achieve the first best by offering asymmetric group contracts. (C) 2014 Elsevier B.V. All

  4. Asymmetric morphology of the propagating jet

    Science.gov (United States)

    Hardee, Philip E.; Norman, Michael L.

    1990-12-01

    Simulations of slab jets propagating in constant atmospheres are reported for a range of jet velocities and Mach numbers. At early times, the jet maintains approximate axisymmetry within a backflowing cocoon. When the jet has penetrated farther into the external medium, the symmetry is broken by sideways oscillation and the leading edge of the jet moves about within a growing lobe. The oscillation results from nonlinear resonant amplification of the initial perturbation by the Kelvin-Helmholtz instability. Finally, the jet flaps chaotically within the growing lobe. The flapping is driven by turbulent vortices in the lobe. The basic picture of Scheuer's (1982) 'dentist's drill' model of the physical processes underlying asymmetric morphologies in radio galaxies is confirmed. The fluid motions in the lobe are found to govern the location of the drill bit. The morphology is time-dependent on relatively short time scales.

  5. Asymmetric Beam Combination for Optical Interferometry

    CERN Document Server

    Monnier, J D

    2001-01-01

    Optical interferometers increasingly use single-mode fibers as spatial filters to convert varying wavefront distortion into intensity fluctuations which can be monitored for accurate calibration of fringe amplitudes. Here I propose using an asymmetric coupler to allow the photometric intensities of each telescope beam to be measured at the same time as the fringe visibility, but without the need for dedicated photometric outputs, which reduce the light throughput in the interferometric channels. In the read-noise limited case often encountered in the infrared, I show that a 53% improvement in signal-to-noise ratio for the visibility amplitude measurement is achievable, when compared to a balanced coupler setup with 50% photometric taps (e.g., the FLUOR experiment). In the Poisson-noise limit appropriate for visible light, the improvement is reduced to only ~8%. This scheme also reduces the cost and complexity of the beam combination since fewer components and detectors are required, and can be extended to mor...

  6. Asymmetric Ferromagnet-Superconductor-Ferromagnet Switch

    Energy Technology Data Exchange (ETDEWEB)

    Cadden-Zimansky, P.; Bazaliy, Ya.B.; Litvak, L.M.; Jiang, J.S.; Pearson, J.; Gu, J.Y.; You, Chun-Yeol; Beasley, M.R.; Bader, S.D.

    2011-11-04

    In layered ferromagnet-superconductor-ferromagnet F{sub 1} /S/F{sub 2} structures, the critical temperature T{sub c} of the superconductors depends on the magnetic orientation of the ferromagnetic layers F{sub 1} and F{sub 2} relative to each other. So far, the experimentally observed magnitude of change in T{sub c} for structures utilizing weak ferromagnets has been 2 orders of magnitude smaller than is expected from calculations. We theoretically show that such a discrepancy can result from the asymmetry of F/S boundaries, and we test this possibility by performing experiments on structures where F{sub 1} and F{sub 2} are independently varied. Our experimental results indicate that asymmetric boundaries are not the source of the discrepancy. If boundary asymmetry is causing the suppressed magnitude of T{sub c} changes, it may only be possible to detect in structures with thinner ferromagnetic layers.

  7. Magnetoresistive system with concentric ferromagnetic asymmetric nanorings

    Energy Technology Data Exchange (ETDEWEB)

    Avila, J. I., E-mail: javila@ulg.ac.be; Tumelero, M. A.; Pasa, A. A.; Viegas, A. D. C. [Laboratório de Filmes Finos e Superfícies (LFFS), Departamento de Física, Universidade Federal de Santa Catarina, CP 476 Florianópolis (Brazil)

    2015-03-14

    A structure consisting of two concentric asymmetric nanorings, each displaying vortex remanent states, is studied with micromagnetic calculations. By orienting in suitable directions, both the asymmetry of the rings and a uniform magnetic field, the vortices chiralities can be switched from parallel to antiparallel, obtaining in this way the analogue of the ferromagnetic and antiferromagnetic configurations found in bar magnets pairs. Conditions on the thickness of single rings to obtain vortex states, as well as formulas for their remanent magnetization are given. The concentric ring structure enables the creation of magnetoresistive systems comprising the qualities of magnetic nanorings, such as low stray fields and high stability. A possible application is as contacts in spin injection in semiconductors, and estimations obtained here of magnetoresistance change for a cylindrical spin injection based device show significant variations comparable to linear geometries.

  8. Asymmetric correlations on the Croatian equity market

    Directory of Open Access Journals (Sweden)

    Davor Kunovac

    2011-03-01

    Full Text Available This paper compares the equity market in Croatia in bad (bear or turbulent and good (bull, calm market conditions. The two market regimes are formally identifi ed under the Markov Regime Switching (MRS framework. The analysis conducted suggests that correlations between equity prices are more than twice as high during bear than in bull markets. This result holds both for the shares included in the CROBEX and for the relationship among various European equity indices.In the context of international diversifi cation the result suggests only a limited benefi t that foreign investors can count on when diversifying their portfolios by expanding to developing European markets. In addition, by evaluating a portfolio optimization model that takes asymmetric correlations into account in an out-of-sample exercise, this paper also illustrates the losses that may occur if the asymmetry is ignored in practice.

  9. Distributed Function Computation in Asymmetric Communication Scenarios

    CERN Document Server

    Agnihotri, Samar

    2009-01-01

    We consider the distributed function computation problem in asymmetric communication scenarios, where the sink computes some deterministic function of the data split among N correlated informants. The distributed function computation problem is addressed as a generalization of distributed source coding (DSC) problem. We are mainly interested in minimizing the number of informant bits required, in the worst-case, to allow the sink to exactly compute the function. We provide a constructive solution for this in terms of an interactive communication protocol and prove its optimality. The proposed protocol also allows us to compute the worst-case achievable rate-region for the computation of any function. We define two classes of functions: lossy and lossless. We show that, in general, the lossy functions can be computed at the sink with fewer number of informant bits than the DSC problem, while computation of the lossless functions requires as many informant bits as the DSC problem.

  10. Asymmetric pneumatization of the petrous apex.

    Science.gov (United States)

    Roland, P S; Meyerhoff, W L; Judge, L O; Mickey, B E

    1990-07-01

    Three patients with high-intensity MR signals from one petrous apex, but nonpathologic fine-cut computed tomography are reported. In two of the three patients, normal bone marrow within the petrous apex on one side is believed to have generated the high-intensity signal. In one of the three patients, the etiology of the MR image remains obscure, but may represent the earliest stages of petrous cholesterol granuloma or mucocele. We have reviewed 500 head CT scans performed for non-otologic reasons, in an attempt to establish the frequency of this finding. The literature on MR and CT imaging of the petrous apex and asymmetric pneumatization of the petrous apex is reviewed. PMID:2117735

  11. Asymmetric exclusion processes with shuffled dynamics

    International Nuclear Information System (INIS)

    The asymmetric simple exclusion process (ASEP) with periodic boundary conditions is investigated for shuffled dynamics. In this type of update, in each discrete timestep the particles are updated in a random sequence. Such an update is important for several applications, e.g., for certain models of pedestrian flow in two dimensions. For the ASEP with shuffled dynamics and a related truncated process exact results are obtained for deterministic motion (p = 1). Since the shuffled dynamics is intrinsically stochastic, also this case is nontrivial. For the case of stochastic motion (0 < p < 1) it is shown that, in contrast to all other updates studied previously, the ASEP with shuffled update does not have a product measure steady state. Approximative formulae for the steady-state distribution and fundamental diagram are derived that are in very good agreement with simulation data

  12. Asymmetric EPR entanglement in continuous variable systems

    CERN Document Server

    Wagner, Katherine; Armstrong, Seiji; Morizur, Jean-Francois; Lam, Ping Koy; Bachor, Hans-Albert

    2012-01-01

    Continuous variable entanglement can be produced in nonlinear systems or via interference of squeezed states. In many of optical systems, such as parametric down conversion or interference of optical squeezed states, production of two perfectly symmetric subsystems is usually used for demonstrating the existence of entanglement. This symmetry simplifies the description of the concept of entanglement. However, asymmetry in entanglement may arise naturally in a real experiment, or be intentionally introduced in a given quantum information protocol. These asymmetries can emerge from having the output beams experience different losses and environmental contamination, or from the availability of non-identical input quantum states in quantum communication protocols. In this paper, we present a visualisation of entanglement using quadrature amplitude plots of the twin beams. We quantitatively discuss the strength of asymmetric entanglement using EPR and inseparability criteria and theoretically show that the optimal...

  13. Algebraic Davis Decomposition and Asymmetric Doob Inequalities

    Science.gov (United States)

    Hong, Guixiang; Junge, Marius; Parcet, Javier

    2016-09-01

    In this paper we investigate asymmetric forms of Doob maximal inequality. The asymmetry is imposed by noncommutativity. Let {({M}, τ)} be a noncommutative probability space equipped with a filtration of von Neumann subalgebras {({M}_n)_{n ≥ 1}}, whose union {bigcup_{n≥1}{M}_n} is weak-* dense in {{M}}. Let {{E}_n} denote the corresponding family of conditional expectations. As an illustration for an asymmetric result, we prove that for {1 < p < 2} and {x in L_p({M},τ)} one can find {a, b in L_p({M},τ)} and contractions {u_n, v_n in {M}} such that {E}_n(x) = a u_n + v_n b quad and quad max big{ |a|_p,|b|_p big} ≤ c_p |x|_p. Moreover, it turns out that {a u_n} and {v_n b} converge in the row/column Hardy spaces {{H}_p^r({M})} and {{H}_p^c({M})} respectively. In particular, this solves a problem posed by the Defant and Junge in 2004. In the case p = 1, our results establish a noncommutative form of the Davis celebrated theorem on the relation betwe en martingale maximal and square functions in L 1, whose noncommutative form has remained open for quite some time. Given {1 ≤ p ≤ 2}, we also provide new weak type maximal estimates, which imply in turn left/right almost uniform convergence of {{E}_n(x)} in row/column Hardy spaces. This improves the bilateral convergence known so far. Our approach is based on new forms of Davis martingale decomposition which are of independent interest, and an algebraic atomic description for the involved Hardy spaces. The latter results are new even for commutative von Neumann algebras.

  14. The evolution of cooperation in asymmetric systems

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Explaining the "Tragedy of the Commons" of the evolution of cooperation remains one of the greatest problems for both biology and social science.Asymmetrical interaction,which is one of the most important characteristics of cooperative systems,has not been sufficiently considered in the existing models of the evolution of cooperation.Considering the inequality in the number and payoff between the cooperative actors and recipients in cooperation systems,discriminative density-dependent interference competition will occur in limited dispersal systems.Our model and simulation show that the local but not the global stability of a cooperative interaction can be maintained if the utilization of common resource remains unsaturated,which can be achieved by density-dependent restraint or competition among the cooperative actors.More intense density dependent interference competition among the cooperative actors and the ready availability of the common resource,with a higher intrinsic contribution ratio of a cooperative actor to the recipient,will increase the probability of cooperation.The cooperation between the recipient and the cooperative actors can be transformed into conflict and,it oscillates chaotically with variations of the affecting factors under different environmental or ecological conditions.The higher initial relatedness(i.e.similar to kin or reciprocity relatedness),which is equivalent to intrinsic contribution ratio of a cooperative actor to the recipient,can be selected for by penalizing less cooperative or cheating actors but rewarding cooperative individuals in asymmetric systems.The initial relatedness is a pivot but not the aim of evolution of cooperation.This explains well the direct conflict observed in almost all cooperative systems.

  15. PEP-II: An asymmetric B factory

    International Nuclear Information System (INIS)

    In this report, the authors have described an updated conceptual design for the high-luminosity Asymmetric B Factory (PEP-II) to be built in the PEP tunnel culmination of more than four years of effort aimed at the design and construction of an asymmetric e+e- collider capable of achieving a luminosity of L = 3 x 1033 cm-2 s-1. All aspects of the conceptual design were scrutinized in March 1991 by a DOE technical review committee chaired by Dr. L. Edward Temple. The design was deemed feasible and capable of achieving its physics goals. Furthermore, the cost estimate, schedule, and management plan for the project were fully endorsed by the committee. This updated conceptual design report captures the technical progress since the March 1991 review and reflects the lower cost estimate corresponding to the improved design. Although the PEP-II design has continued to evolve, no technical scope changes have been made that invalidate the conclusion of the DOE review. The configuration adopted utilizes two storage rings, an electron ring operating at 9 GeV and a positron ring at 3.1 GeV, each with a circumference of 2200 m. The high-energy ring is an upgrade of the PEP storage ring at SLAC; all PEP magnets and most power supplies will be reused. The upgrade consists primarily of replacing the PEP vacuum chamber and RF system with newly designed versions optimized for the high-current environment of PEP-II. The low-energy ring will be newly constructed and will be situated atop the high-energy ring in the PEP tunnel. Utilities already installed in the PEP tunnel are largely sufficient to operate the two PEP-II storage rings

  16. Special Issue of "Asymmetric Synthesis"%Special Issue of "Asymmetric Synthesis"

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Organic chemistry exploring the world at a molecu- lar level remains essential for our society in the 21st century. Asymmetric synthesis, particularly those em- ploying catalytic approach, is one of the most important research fields in organic synthesis providing chiral compounds in an enantiopure form. The latter is critical since the two enantiomers of one chiral compound, in many cases, have a different response in biological sys- tems. The huge markets of non-racemic chiral com- pounds as synthetic intermediates, pharmaceuticals,

  17. Modified Quasi-Steady State Model of DC System for Transient Stability Simulation under Asymmetric Faults

    Directory of Open Access Journals (Sweden)

    Jun Liu

    2015-01-01

    Full Text Available As using the classical quasi-steady state (QSS model could not be able to accurately simulate the dynamic characteristics of DC transmission and its controlling systems in electromechanical transient stability simulation, when asymmetric fault occurs in AC system, a modified quasi-steady state model (MQSS is proposed. The model firstly analyzes the calculation error induced by classical QSS model under asymmetric commutation voltage, which is mainly caused by the commutation voltage zero offset thus making inaccurate calculation of the average DC voltage and the inverter extinction advance angle. The new MQSS model calculates the average DC voltage according to the actual half-cycle voltage waveform on the DC terminal after fault occurrence, and the extinction advance angle is also derived accordingly, so as to avoid the negative effect of the asymmetric commutation voltage. Simulation experiments show that the new MQSS model proposed in this paper has higher simulation precision than the classical QSS model when asymmetric fault occurs in the AC system, by comparing both of them with the results of detailed electromagnetic transient (EMT model of the DC transmission and its controlling system.

  18. The deal with diel: Temperature fluctuations, asymmetrical warming, and ubiquitous metals contaminants.

    Science.gov (United States)

    Hallman, Tyler A; Brooks, Marjorie L

    2015-11-01

    Climate projections over the next century include disproportionately warmer nighttime temperatures ("asymmetrical warming"). Cool nighttime temperatures lower metabolic rates of aquatic ectotherms. In contaminated waters, areas with cool nights may provide thermal refugia from high rates of daytime contaminant uptake. We exposed Cope's gray tree frogs (Hyla chrysoscelis), southern leopard frogs (Lithobates sphenocephalus), and spotted salamanders (Ambystoma maculatum) to five concentrations of a mixture of cadmium, copper, and lead under three to four temperature regimes, representing asymmetrical warming. At concentrations with intermediate toxicosis at test termination (96 h), temperature effects on acute toxicity or escape distance were evident in all study species. Asymmetrical warming (day:night, 22:20 °C; 22:22 °C) doubled or tripled mortality relative to overall cooler temperatures (20:20 °C) or cool nights (22:18 °C). Escape distances were 40-70% shorter under asymmetrical warming. Results suggest potentially grave ecological impacts from unexpected toxicosis under climate change.

  19. Scaling of triple differential cross-sections for asymmetric (, 2) process on helium isoelectronic ions by fast electrons

    Indian Academy of Sciences (India)

    M K Srivastava

    2005-01-01

    A simple scaling law is obtained for asymmetric (, 2) process on helium isoelectronic ions by fast electrons. It is based on treating the targets as having one active electron moving in the effective Coulomb field of the atomic core with an effective charge ' = − 5/8. This effective charge is also used in the description of the scattered and ejected electrons. The model has been tested against other available (, 2) results on helium in asymmetric geometry. The scaling law is found to work reasonably well for fast incident electrons and becomes increasingly accurate as target increases.

  20. Moment methods for solving asymmetrically driven rf probes in the collisional ionospheric magnetoplasma

    International Nuclear Information System (INIS)

    The moment method is discussed, and the application of this method for solving asymmetrically driven RF probes in the collisional and warm ionospheric magnetoplasma is presented. The first three velocity moments of the Boltzmann transport equations are used for the description of the plasma. No interrelation between the electromagnetic mode and the plasma mode is assumed. The effects of these two modes on the antenna impedance are compared and it is shown that the electromagnetic effect is negligible with respect to the plasma effect under certain conditions. The absorptive boundary condition is considered so that the ion sheath may be treated as collapsed. Typical monopole, symmetrical dipole and asymmetrical dipole antennas are considered and many impedance curves are presented. Since the antenna impedance curves are related to all the plasma parameters, the methods of the prediction of plasma parameters from the measured antenna impedances are mentioned. Further research is proposed to eliminate the quasi-static restriction