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Sample records for asymmetric exclusion process

  1. 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

  2. Large deviation function of the partially asymmetric exclusion process.

    Science.gov (United States)

    Lee, D S; Kim, D

    1999-06-01

    The large deviation function obtained recently by Derrida and Lebowitz [Phys. Rev. Lett. 80, 209 (1998)] for the totally asymmetric exclusion process is generalized to the partially asymmetric case in the scaling limit. The asymmetry parameter rescales the scaling variable in a simple way. The finite-size corrections to the universal scaling function and the universal cumulant ratio are also obtained to the leading order. PMID:11969632

  3. 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.

  4. Asymmetric exclusion process with a dynamic roadblock and open boundaries

    Science.gov (United States)

    Sahoo, Mamata; Klumpp, Stefan

    2016-08-01

    Motivated by complex transport processes occurring in nature, we study a totally asymmetric simple exclusion process (TASEP) with a dynamic ‘roadblock’ particle. The roadblock particle blocks the traffic of moving particles while bound to the lattice, but can stochastically unbind or switch off, thus enabling the traffic to pass. We use simulations to study the dependence of the particle flux on the on/off switching dynamics of the roadblock, which exhibits a surprisingly rich dynamic behaviour. In particular, unlike in other studied TASEP variants with defects, here we observe that the particle flux is affected by the roadblock even in the initiation-limited or low density phase if the roadblock dynamics is slow. Rapid switching off the roadblock results in the typical behaviour of a TASEP with a defect/pause with reduced maximal current, but no effect of the roadblock on the flux in the initiation-limited phase. Moreover, in an intermediate range of roadblock rates, the particle current is found to be system-size dependent.

  5. Theoretical analysis and simulation for a facilitated asymmetric exclusion process

    Science.gov (United States)

    Hao, Qing-Yi; Chen, Zhe; Sun, Xiao-Yan; Liu, Bing-Bing; Wu, Chao-Yun

    2016-08-01

    Driven diffusive systems are important models in nonequilibrium state statistical mechanics. This paper studies an asymmetric exclusion process model with nearest rear neighbor interactions associated with energy. The exact flux expression of the model is obtained by a cluster mean-field method. Based on the flux expression, the properties of the fundamental diagram have been investigated in detail. To probe the energy's influence on the coarsening process of the system, Monte Carlo simulations are carried out to acquire the monotonic phase boundary in energy-density space. Above the phase boundary, the system is inhomogeneous and the normalized residence distribution p (s ) is nonmonotonically decreasing. Under the phase boundary, the system is homogeneous and p (s ) is monotonically decreasing. Further study comparatively shows that the system has turned into a microscopic inhomogeneous state from a homogeneous state before the system current arrives at maximum, if nearest rear neighbor interactions are strong. Our findings offer insights to deeply understand the dynamic features of nonequilibrium state systems.

  6. Non-stationary probabilities for the asymmetric exclusion process on a ring

    Indian Academy of Sciences (India)

    V B Priezzhev

    2005-06-01

    A solution of the master equation for a system of interacting particles for finite time and particle density is presented. By using a new form of the Bethe ansatz, the totally asymmetric exclusion process on a ring is solved for arbitrary initial conditions and time intervals.

  7. Shocks induced by junctions in totally asymmetric simple exclusion processes under periodic boundary condition

    Science.gov (United States)

    Sun, Xiaoyan; Xie, Yanbo; He, Zhiwei; Wang, Binghong

    2011-07-01

    This Letter investigates a totally asymmetric simple exclusion process (TASEP) with junctions in a one-dimensional transport system. Parallel update rules and periodic boundary condition are adopted. Two cases corresponding to different update rules are studied. The results show that the stationary states of system mainly depend on the selection behavior of particle at the bifurcation point.

  8. Dynamic screening in a two-species asymmetric exclusion process.

    Science.gov (United States)

    Kim, Kyung Hyuk; den Nijs, Marcel

    2007-08-01

    The dynamic scaling properties of the one-dimensional Burgers equation are expected to change with the inclusion of additional conserved degrees of freedom. We study this by means of one-dimensional (1D) driven lattice gas models that conserve both mass and momentum. The most elementary version of this is the Arndt-Heinzel-Rittenberg (AHR) process, which is usually presented as a two-species diffusion process, with particles of opposite charge hopping in opposite directions and with a variable passing probability. From the hydrodynamics perspective this can be viewed as two coupled Burgers equations, with the number of positive and negative momentum quanta individually conserved. We determine the dynamic scaling dimension of the AHR process from the time evolution of the two-point correlation functions, and find numerically that the dynamic critical exponent is consistent with simple Kardar-Parisi-Zhang- (KPZ) type scaling. We establish that this is the result of perfect screening of fluctuations in the stationary state. The two-point correlations decay exponentially in our simulations and in such a manner that in terms of quasiparticles, fluctuations fully screen each other at coarse grained length scales. We prove this screening rigorously using the analytic matrix product structure of the stationary state. The proof suggests the existence of a topological invariant. The process remains in the KPZ universality class but only in the sense of a factorization, as (KPZ)2. The two Burgers equations decouple at large length scales due to the perfect screening.

  9. Dynamic screening in a two-species asymmetric exclusion process

    Science.gov (United States)

    Kim, Kyung Hyuk; den Nijs, Marcel

    2007-08-01

    The dynamic scaling properties of the one-dimensional Burgers equation are expected to change with the inclusion of additional conserved degrees of freedom. We study this by means of one-dimensional (1D) driven lattice gas models that conserve both mass and momentum. The most elementary version of this is the Arndt-Heinzel-Rittenberg (AHR) process, which is usually presented as a two-species diffusion process, with particles of opposite charge hopping in opposite directions and with a variable passing probability. From the hydrodynamics perspective this can be viewed as two coupled Burgers equations, with the number of positive and negative momentum quanta individually conserved. We determine the dynamic scaling dimension of the AHR process from the time evolution of the two-point correlation functions, and find numerically that the dynamic critical exponent is consistent with simple Kardar-Parisi-Zhang- (KPZ) type scaling. We establish that this is the result of perfect screening of fluctuations in the stationary state. The two-point correlations decay exponentially in our simulations and in such a manner that in terms of quasiparticles, fluctuations fully screen each other at coarse grained length scales. We prove this screening rigorously using the analytic matrix product structure of the stationary state. The proof suggests the existence of a topological invariant. The process remains in the KPZ universality class but only in the sense of a factorization, as (KPZ)2 . The two Burgers equations decouple at large length scales due to the perfect screening.

  10. Power Spectra of a Totally Asymmetric Simple Exclusion Process with Finite Resources

    Science.gov (United States)

    Cook, L. Jonathan; Zia, Royce K. P.

    2010-03-01

    In a cell, a mRNA has only a finite number of ribosomes to use during protein synthesis. We take this constraint into account in the modeling of translation by a totally asymmetric simple exclusion process (TASEP). Through Monte Carlo simulations and analytical methods, we study the power spectrum of the total particle occupancy of the TASEP. New features are found, such as a severe suppression at low frequencies. We formulate a theory based on a linearized Langevin equation with discrete space and time. With good agreement between the theoretical approach and the simulations, we gain some insight in how finite resources affect a TASEP.

  11. 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.

  12. The Braess Paradox in a network of totally asymmetric exclusion processes

    CERN Document Server

    Bittihn, Stefan

    2016-01-01

    We study the Braess paradox in the transport network as originally proposed by Braess with totally asymmetric exclusion processes (TASEPs) on the edges. The Braess paradox describes the counterintuitive situation where adding an additional edge to a road network leads to a user optimum with higher traveltimes for all network users. Traveltimes on the TASEPs are nonlinear in the density and jammed states can occur due to the microscopic exclusion principle. Furthermore the individual edges influence each other. This leads to a much more realistic description of traffic-like transport on the network than in previously studied linear macroscopic mathematical models. Furthermore the stochastic dynamics allows to explore the effects of fluctuations on the network performance. We observe that for low densities the added edge leads to lower traveltimes. For slightly higher densities the Braess paradox in its classical sense occurs in a small density regime. In a large regime of intermediate densities strong fluctuat...

  13. Numerical method for accessing the universal scaling function for a multiparticle discrete time asymmetric exclusion process.

    Science.gov (United States)

    Chia, Nicholas; Bundschuh, Ralf

    2005-11-01

    In the universality class of the one-dimensional Kardar-Parisi-Zhang (KPZ) surface growth, Derrida and Lebowitz conjectured the universality of not only the scaling exponents, but of an entire scaling function. Since and Derrida and Lebowitz's original publication [Phys. Rev. Lett. 80, 209 (1998)] this universality has been verified for a variety of continuous-time, periodic-boundary systems in the KPZ universality class. Here, we present a numerical method for directly examining the entire particle flux of the asymmetric exclusion process (ASEP), thus providing an alternative to more difficult cumulant ratios studies. Using this method, we find that the Derrida-Lebowitz scaling function (DLSF) properly characterizes the large-system-size limit (N--> infinity) of a single-particle discrete time system, even in the case of very small system sizes (N< or =22). This fact allows us to not only verify that the DLSF properly characterizes multiple-particle discrete-time asymmetric exclusion processes, but also provides a way to numerically solve for quantities of interest, such as the particle hopping flux. This method can thus serve to further increase the ease and accessibility of studies involving even more challenging dynamics, such as the open-boundary ASEP. PMID:16383588

  14. Asymmetric simple exclusion processes with complex lattice geometries: A review of models and phenomena

    Institute of Scientific and Technical Information of China (English)

    Liu Ming-Zhe; Li Shao-Da; Wang Rui-Li

    2012-01-01

    We summarize the findings of a large number of studies concerning the totally asymmetric simple exclusion process (TASEP) with complex lattice geometries.The TASEP has been recognized as a paradigm in modeling and analyzing non-equilibrium traffic systems.The paper surveys both the observed physical phenomena and several popular meanfield approaches used to analyze the extended TASEP models.Several interesting physical phenomena,such as phase separation,spontaneous symmetry breaking,and the finite-size effect,have been identified and explained.The future investigations of the extended TASEP with complex lattice geometries are also introduced.This paper may help to obtain a better understanding of non-equilibrium systems.

  15. Time-headway distribution for periodic totally asymmetric exclusion process with various updates

    Science.gov (United States)

    Hrabák, P.; Krbálek, M.

    2016-03-01

    The totally asymmetric exclusion process (TASEP) with periodic boundaries is considered as traffic flow model. The large-L approximation of the stationary state is used for the derivation of the time-headway distribution (an important microscopic characteristic of traffic flow) for the model with generalized update (genTASEP) in both, forward- and backward-sequential representations. The usually used updates, fully-parallel and regular forward- and backward-sequential, are analyzed as special cases of the genTASEP. It is shown that only for those cases, the time-headway distribution is determined by the flow regardless to the density. The qualitative comparison of the results with traffic data demonstrates that the genTASEP with backward order and attractive interaction evinces similar properties of time-headway distribution as the real traffic sample.

  16. Zone inhomogeneity with the random asymmetric simple exclusion process in a one-lane system

    Institute of Scientific and Technical Information of China (English)

    Xiao Song; Cai Jiu-Ju; Liu Fei

    2009-01-01

    In this paper we use theoretical analysis and extensive simulations to study zone inhomogeneity with the random asymmetric simple exclusion process (ASEP). In the inhomogeneous zone, the hopping probability is less than 1. Two typical lattice geometries axe investigated here. In case A, the lattice includes two equal segments. The hopping probability in the left segment is equal to 1, and in the right segment it is equal to p, which is less than 1. In case B, there are three equal segments in the system; the hopping probabilities in the left and right segments are equal to 1, and in the middle segment it is equal to p, which is leas than 1. Through theoretical analysis, we can discover the effect on these systems when p is changed.

  17. PEMODELAN TOTALLY ASYMMETRIC EXCLUSION PROCESS DUA DIMENSI UNTUK LALU LINTAS KENDARAAN PADA PERTIGAAN JALAN YANG SEARAH

    Directory of Open Access Journals (Sweden)

    R Septiana

    2014-06-01

    Full Text Available Abstrak __________________________________________________________________________________________ Penelitian ini mengkaji model dinamik yaitu Totally Asymmetric Exclusion Process (TASEP khususnya dalam dua dimensi (2D. Selain itu akan dibahas pula mengenai syarat batas dan aturan dinamika yang digunakan dalam pemodelan ini. TASEP telah diaplikasikan dalam berbagai bidang, salah satunya ialah pemodelan lalu lintas kendaraan (traffic flow. Sistem dua dimensi yang akan dikaji adalah sistem yang diskrit, yakni sistem ke kisi dua dimensi. Sistem ini dimodifikasi menjadi bentuk pertigaan (junction yang searah. Lebih jauh lagi, kendaraan yang melalui pertigaan dimodelkan sebagai partikel yang melompat dari satu kisi ke ke kisi yang lain. Nilai kepadatan dan rapat arus partikel dalam sistem tersebut ditentukan secara numerik. Persamaan kontinuitas untuk menggambarkan dinamika partikel dalam TASEP diselesaikan menggunakan metode Euler. Profil kepadatan dan rapat arus partikel dipengaruhi oleh laju masukan (input rate dan laju keluaran (output rate lompatan partikel.   Abstract __________________________________________________________________________________________ The research analyzed a dynamic model of Totally Asymmetric Exclusion Process (TASEP, especially in two dimensions (2D and  also the boundary and rules dynamic conditions  used in this modeling. TASEP has been applied in various fields, one of them is the modeling of vehicle traffic. Two-dimensional system that will be studied is the discrete system of two-dimensional lattice system. The system is modified into the form of unidirectional T-junction . Furthermore, the vehicles that pass the junction are modeled as particles that jump from one lattice to another lattice. The value of the density and current density of particles in the system is determined numerically. The continuity equation to describe the dynamics of particles in TASEP is solved by using Euler's method. The profiles of

  18. Emergence of jams in the generalized totally asymmetric simple exclusion process.

    Science.gov (United States)

    Derbyshev, A E; Povolotsky, A M; Priezzhev, V B

    2015-02-01

    The generalized totally asymmetric exclusion process (TASEP) [J. Stat. Mech. (2012) P05014] is an integrable generalization of the TASEP equipped with an interaction, which enhances the clustering of particles. The process interpolates between two extremal cases: the TASEP with parallel update and the process with all particles irreversibly merging into a single cluster moving as an isolated particle. We are interested in the large time behavior of this process on a ring in the whole range of the parameter λ controlling the interaction. We study the stationary state correlations, the cluster size distribution, and the large-time fluctuations of integrated particle current. When λ is finite, we find the usual TASEP-like behavior: The correlation length is finite; there are only clusters of finite size in the stationary state and current fluctuations belong to the Kardar-Parisi-Zhang universality class. When λ grows with the system size, so does the correlation length. We find a nontrivial transition regime with clusters of all sizes on the lattice. We identify a crossover parameter and derive the large deviation function for particle current, which interpolates between the case considered by Derrida-Lebowitz and a single-particle diffusion. PMID:25768476

  19. Phase transition in 2D partially asymmetric simple exclusion process with two species

    International Nuclear Information System (INIS)

    The dynamics of two species of particles undergoing asymmetric simple exclusion process (ASEP) on the 2D lattice are investigated in this paper. A sharp transition from moving phase to jamming phase was shown under periodic boundary conditions. We have developed a mean field analysis for the moving phase by extending the method of [33] and this produces good agreement with simulation results. Two types of jamming phase were observed. In the first type of jamming phase, some particles at the border of the jamming cluster could move back and forth due to the ASEP rule. The first type of jamming phase reduces to the 1D ASEP with a barrier at the boundary of the lattice. We also have analyzed the average hops for the first type of jamming phase by analyzing the 1D ASEP model. The analytical results agree with the simulation results well. Under open boundary conditions, the system exhibits two phases when forward hopping probability q is larger than 0.5. The particles form a wall at the entrance when q is smaller than 0.5. The dependence of the average velocity, the density and the flow rate on the injection probability in the moving phase have also been obtained through mean field analysis. (paper)

  20. Role of the particle's stepping cycle in an asymmetric exclusion process: A model of mRNA translation

    OpenAIRE

    Ciandrini, L.; Stansfield, I; Romano, M. C.

    2009-01-01

    Messenger RNA translation is often studied by means of statistical-mechanical models based on the Asymmetric Simple Exclusion Process (ASEP), which considers hopping particles (the ribosomes) on a lattice (the polynucleotide chain). In this work we extend this class of models and consider the two fundamental steps of the ribosome’s biochemical cycle following a coarse-grained perspective. In order to achieve a better understanding of the underlying biological processes and compare the theoret...

  1. On Decay of Correlations for Exclusion Processes with Asymmetric Boundary Conditions

    CERN Document Server

    Malyshev, V A

    2011-01-01

    We consider a symmetric exclusion process on a discrete interval of $S$ points with various boundary conditions at the endpoints. We study the asymptotic decay of correlations as $S\\to\\infty$. The main result is asymptotic independence of a stationary distribution whem the points are far away from each other. We develop a new recurrent probabilistic approach which is an alternative to Derrida's algebraic technique.

  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. Totally asymmetric simple exclusion process with a time-dependent boundary: interaction between vehicles and pedestrians at intersections

    CERN Document Server

    Ito, Hidetaka

    2014-01-01

    Interaction between vehicles and pedestrians is seen in many areas such as crosswalks and intersections. In this paper, we study a totally asymmetric simple exclusion process with a bottleneck at a boundary caused by an interaction. Due to the time-dependent effect originating from the speed of pedestrians, the flow of the model varies even if the average hopping probability at the last site is the same. We analyze the phenomenon by using two types of approximations: (2+1)-cluster approximation and isolated rarefaction wave approximation. The approximate results capture intriguing features of the model. Moreover, we discuss the situation where vehicles turn right at the intersection by adding a traffic light at the boundary condition. The result suggests that pedestrian scrambles are valid to eliminate traffic congestion in the right turn lane.

  4. Phase-plane analysis of the totally asymmetric simple exclusion process with binding kinetics and switching between antiparallel lanes

    Science.gov (United States)

    Kuan, Hui-Shun; Betterton, Meredith D.

    2016-01-01

    Motor protein motion on biopolymers can be described by models related to the totally asymmetric simple exclusion process (TASEP). Inspired by experiments on the motion of kinesin-4 motors on antiparallel microtubule overlaps, we analyze a model incorporating the TASEP on two antiparallel lanes with binding kinetics and lane switching. We determine the steady-state motor density profiles using phase-plane analysis of the steady-state mean field equations and kinetic Monte Carlo simulations. We focus on the density-density phase plane, where we find an analytic solution to the mean field model. By studying the phase-space flows, we determine the model’s fixed points and their changes with parameters. Phases previously identified for the single-lane model occur for low switching rate between lanes. We predict a multiple coexistence phase due to additional fixed points that appear as the switching rate increases: switching moves motors from the higher-density to the lower-density lane, causing local jamming and creating multiple domain walls. We determine the phase diagram of the model for both symmetric and general boundary conditions. PMID:27627345

  5. Phase-plane analysis of the totally asymmetric simple exclusion process with binding kinetics and switching between antiparallel lanes

    Science.gov (United States)

    Kuan, Hui-Shun; Betterton, Meredith D.

    2016-08-01

    Motor protein motion on biopolymers can be described by models related to the totally asymmetric simple exclusion process (TASEP). Inspired by experiments on the motion of kinesin-4 motors on antiparallel microtubule overlaps, we analyze a model incorporating the TASEP on two antiparallel lanes with binding kinetics and lane switching. We determine the steady-state motor density profiles using phase-plane analysis of the steady-state mean field equations and kinetic Monte Carlo simulations. We focus on the density-density phase plane, where we find an analytic solution to the mean field model. By studying the phase-space flows, we determine the model's fixed points and their changes with parameters. Phases previously identified for the single-lane model occur for low switching rate between lanes. We predict a multiple coexistence phase due to additional fixed points that appear as the switching rate increases: switching moves motors from the higher-density to the lower-density lane, causing local jamming and creating multiple domain walls. We determine the phase diagram of the model for both symmetric and general boundary conditions.

  6. Phase-plane analysis of the totally asymmetric simple exclusion process with binding kinetics and switching between antiparallel lanes

    CERN Document Server

    Kuan, Hui-Shun

    2016-01-01

    Motor protein motion on biopolymers can be described by models related to the totally asymmetric simple exclusion process (TASEP). Inspired by experiments on the motion of kinesin-4 motors on antiparallel microtubule overlaps, we analyze a model incorporating the TASEP on two antiparallel lanes with binding kinetics and lane switching. We determine the steady-state motor density profiles using phase plane analysis of the steady-state mean field equations and kinetic Monte Carlo simulations. We focus on the the density-density phase plane, where we find an analytic solution to the mean-field model. By studying the phase space flows, we determine the model's fixed points and their changes with parameters. Phases previously identified for the single-lane model occur for low switching rate between lanes. We predict a new multiple coexistence phase due to additional fixed points that appear as the switching rate increases: switching moves motors from the higher-density to the lower-density lane, causing local jamm...

  7. Position dependence of the particle density in a double-chain section of a linear network in a totally asymmetric simple exclusion process

    Science.gov (United States)

    Pesheva, N. C.; Brankov, J. G.

    2013-06-01

    We report here results on the study of the totally asymmetric simple exclusion process, defined on an open network, consisting of head and tail simple-chain segments with a double-chain section inserted in between. Results of numerical simulations for relatively short chains reveal an interesting feature of the network. When the current through the system takes its maximum value, a simple translation of the double-chain section forward or backward along the network leads to a sharp change in the shape of the density profiles in the parallel chains, thus affecting the total number of particles in that part of the network. In the symmetric case of equal injection and ejection rates α=β>1/2 and equal lengths of the head and tail sections, the density profiles in the two parallel chains are almost linear, characteristic of the coexistence line (shock phase). Upon moving the section forward (backward), their shape changes to the one typical for the high- (low-) density phases of a simple chain. The total bulk density of particles in a section with a large number of parallel chains is evaluated too. The observed effect might have interesting implications for the traffic flow control as well as for biological transport processes in living cells. An explanation of this phenomenon is offered in terms of a finite-size dependence of the effective injection and ejection rates at the ends of the double-chain section.

  8. Dynamical phase transitions in totally asymmetric simple exclusion processes with two types of particles under periodically driven boundary conditions

    Science.gov (United States)

    Yeşil, Ayşe Ferhan; Yalabik, M. Cemal

    2016-01-01

    Driven diffusive systems have provided simple models for nonequilibrium systems with nontrivial structures. Steady-state behavior of these systems with constant boundary conditions have been studied extensively. Comparatively less work has been carried out on the responses of these systems to time-dependent parameters. We report the modifications to the probability density function of a two-particle exclusion model in response to a periodically changing perturbation to its boundary conditions. The changes in the shape of the distribution as a function of the frequency of the perturbation contains considerable structure. A dynamical phase transition in which the system response changes abruptly as a function of perturbation frequency was observed. We interpret this structure to be a consequence of the existence of a typical time scale associated with the dynamics of density shock profiles within the system.

  9. Hard exclusive QCD processes

    Energy Technology Data Exchange (ETDEWEB)

    Kugler, W.

    2007-01-15

    Hard exclusive processes in high energy electron proton scattering offer the opportunity to get access to a new generation of parton distributions, the so-called generalized parton distributions (GPDs). This functions provide more detailed informations about the structure of the nucleon than the usual PDFs obtained from DIS. In this work we present a detailed analysis of exclusive processes, especially of hard exclusive meson production. We investigated the influence of exclusive produced mesons on the semi-inclusive production of mesons at fixed target experiments like HERMES. Further we give a detailed analysis of higher order corrections (NLO) for the exclusive production of mesons in a very broad range of kinematics. (orig.)

  10. Determinantal Representation of the Time-Dependent Stationary Correlation Function for the Totally Asymmetric Simple Exclusion Model

    Directory of Open Access Journals (Sweden)

    Nikolay M. Bogoliubov

    2009-04-01

    Full Text Available The basic model of the non-equilibrium low dimensional physics the so-called totally asymmetric exclusion process is related to the 'crystalline limit' (q → ∞ of the SU_q(2 quantum algebra. Using the quantum inverse scattering method we obtain the exact expression for the time-dependent stationary correlation function of the totally asymmetric simple exclusion process on a one dimensional lattice with the periodic boundary conditions.

  11. Exact results for the one dimensional asymmetric exclusion model

    Energy Technology Data Exchange (ETDEWEB)

    Derrida, B.; Evans, M.R.; Pasquier, V. [CEA Centre d`Etudes de Saclay, 91 - Gif-sur-Yvette (France). Service de Physique Theorique; Hakim, V. [Ecole Normale Superieure, 75 - Paris (France)

    1993-12-31

    The asymmetric exclusion model describes a system of particles hopping in a preferred direction with hard core repulsion. These particles can be thought of as charged particles in a field, as steps of an interface, as cars in a queue. Several exact results concerning the steady state of this system have been obtained recently. The solution consists of representing the weights of the configurations in the steady state as products of non-commuting matrices. (author).

  12. An exclusion process with dynamic roadblocks

    Science.gov (United States)

    Ning, Guo; Jin-Yong, Chen; Mao-Bin, Hu; Rui, Jiang

    2016-06-01

    We study an exclusion process with multiple dynamic roadblocks. Each roadblock can move diffusively forward or backward with different rates, as well as unbind from/rebind to a free site. By Monte Carlo simulations, the two moving types are investigated in combination of roadblock number. The case of only diffusive roadblocks shows an asymmetric current-density relation. The case of only long-range jumping roadblocks presents that flux decreases with increasing roadblock number. Project supported by the National Basic Research Program of China (Grant No. 2012CB725404) and the National Natural Science Foundation of China (Grant Nos. 11422221, 71171185, and 71371175).

  13. Exclusive processes in quantum chromodynamics

    International Nuclear Information System (INIS)

    Large momentum transfer exclusive processes and the short distance structure of hadronic wave functions can be systematically analyzed within the context of perturbative QCD. Predictions for meson form factors, two-photon processes γγ → M anti M, hadronic decays of heavy quark systems, and a number of other related QCD phenomena are reviewed

  14. Exclusive processes at Jefferson Lab

    Indian Academy of Sciences (India)

    Haiyan Gao

    2003-11-01

    Mapping the transition from strongly interacting, non-perturbative quantum chromodynamics, where nucleon–meson degrees of freedom are effective to perturbative QCD of quark and gluon degrees of freedom, is one of the most fundamental, challenging tasks in nuclear and particle physics. Exclusive processes such as proton–proton elastic scattering, meson photoproduction, and deuteron photodisintegration have been pursued extensively at many laboratories over the years in the search for such a transition, particularly at Jefferson Lab in recent years, taking the advantage of the high luminosity capability of the CEBAF facility. In this talk, I review recent results from Jefferson Lab on deuteron photodisintegration and photopion production processes and the future 12 GeV program.

  15. HERMES Measurements of Hard-Exclusive Processes

    Energy Technology Data Exchange (ETDEWEB)

    Marianski, Bohdan

    2008-11-15

    Three HERMES measurements of hard-exclusive processes usefull for testing Generalized Parton Distributions (GPDs) are described. Firstly, Spin Density Matrix Elements (SDMEs) are determined from exclusive diffractive {rho}{sup 0} and {phi} electroproduction in the HERMES experiment at 27.5 GeV beam energy. Then, Transverse Target Spin Asymmetry (TTSA) in exclusive {rho}{sup 0} production and in Deeply Virtual Compton Scattering (DVCS) process on a transversally polarized hydrogen target is determined.

  16. Competitive exclusion principle in ecology and absolute asymmetric synthesis in chemistry.

    Science.gov (United States)

    Ribó, Josep M; Hochberg, David

    2015-10-01

    The key concepts underlying the Frank model (1953) for spontaneous asymmetric synthesis in chemistry are traced back to the pioneering works of Volterra (1926) and Lotka (1932) on biological species competition. The Lotka-Volterra (L-V) two-species exclusive competition model reduces to the Frank model for the special case of distinguishable but degenerate species (i.e., the enantiomers). The important ecological principle of competitive exclusion, originally derived from the L-V two-competitors model, is a consequence of sufficiently antagonistic interactions between the species competing for limited common resources, or mutual inhibition, as the term is known in the chemical literature on absolute asymmetric synthesis. The L-V and Frank models are described by the same general differential equations, nevertheless a crucial thermodynamic distinction between these models is necessary to correlate ecological selection and chemical selectivity arising from 1) the absence of reversibility in biological transformations, in marked contrast to chemical reactions, and 2) the constraints in chemical scenarios on the reaction rate constants required to fulfill the principle of micro-reversibility. PMID:26301597

  17. Self-organized criticality in asymmetric exclusion model with noise for freeway traffic

    Science.gov (United States)

    Nagatani, Takashi

    1995-02-01

    The one-dimensional asymmetric simple-exclusion model with open boundaries for parallel update is extended to take into account temporary stopping of particles. The model presents the traffic flow on a highway with temporary deceleration of cars. Introducing temporary stopping into the asymmetric simple-exclusion model drives the system asymptotically into a steady state exhibiting a self-organized criticality. In the self-organized critical state, start-stop waves (or traffic jams) appear with various sizes (or lifetimes). The typical interval between consecutive jams scales as ≃ Lv with v = 0.51 ± 0.05 where L is the system size. It is shown that the cumulative jam-interval distribution Ns( L) satisfies the finite-size scaling form ( Ns( L) ≃ L- vf( s/ Lv). Also, the typical lifetime ≃ Lv‧ with v‧ = 0.52 ± 0.05. The cumulative distribution Nm( L) of lifetimes satisfies the finite-size scaling form Nm( L)≃ L-1g( m/ Lv‧).

  18. Asymmetric Aldol Reaction with Formaldehyde: a Challenging Process.

    Science.gov (United States)

    Meninno, Sara; Lattanzi, Alessandra

    2016-08-01

    The asymmetric aldol reaction with formaldehyde is a fundamental carbon-carbon bond-forming reaction in organic synthesis, as well as in the quest of the origin of life, as it is thought to have been the first "molecular brick" involved in the synthetic path to complex sugars. Products of aldol reactions, i.e., the β-hydroxy carbonyl compounds, are versatile building blocks used to access a great variety of functionalised molecules. The employment of formaldehyde, as a C1 symmetric electrophile, in aldol reactions can be likely considered the most challenging, yet simplest, process to introduce a hydroxymethyl group in an asymmetric fashion. In this account, an overview of the progress achieved in the asymmetric metal- and organocatalysed aldol reaction, using readily available formalin or paraformaldehyde sources, is illustrated. Our recent contribution to this area, with the application of asymmetric hydroxymethylation in cascade processes for the synthesis of γ-butyrolactones, is also shown. PMID:27328802

  19. Exclusive processes at high momentum transfer

    CERN Document Server

    Radyushkin, Anatoly; Stoker, Paul

    2002-01-01

    This book focuses on the physics of exclusive processes at high momentum transfer and their description in terms of generalized parton distributions, perturbative QCD, and relativistic quark models. It covers recent developments in the field, both theoretical and experimental.

  20. Imaging partons in exclusive scattering processes

    Energy Technology Data Exchange (ETDEWEB)

    Diehl, Markus

    2012-06-15

    The spatial distribution of partons in the proton can be probed in suitable exclusive scattering processes. I report on recent performance estimates for parton imaging at a proposed Electron-Ion Collider.

  1. Overview of HERMES Results on Exclusive Processes

    OpenAIRE

    Movsisyan Aram

    2015-01-01

    An overview of HERMES results on measurements of hard exclusive electroproduction of real photons and mesons on hydrogen and deuterium targets is presented. Experimental measurements of hard exclusive processes are commonly described within the formalism of generalized parton distributions (GPDs), which provide a unified description of the structure of hadrons embedding longitudinal-momentum distributions (ordinary PDFs) and transverse-position information (form factors). The HERMES experimen...

  2. Spatiotemporally Complete Condensation in a Non-Poissonian Exclusion Process

    Science.gov (United States)

    Concannon, Robert J.; Blythe, Richard A.

    2014-02-01

    We investigate a non-Poissonian version of the asymmetric simple exclusion process, motivated by the observation that coarse graining the interactions between particles in complex systems generically leads to a stochastic process with a non-Markovian (history-dependent) character. We characterize a large family of one-dimensional hopping processes using a waiting-time distribution for individual particle hops. We find that when its variance is infinite, a real-space condensate forms that is complete in space (involves all particles) and time (exists at almost any given instant) in the thermodynamic limit. The mechanism for the onset and stability of the condensate is rather subtle and depends on the microscopic dynamics subsequent to a failed particle hop attempt.

  3. Overview of HERMES Results on Exclusive Processes

    Science.gov (United States)

    Movsisyan, Aram

    2015-01-01

    An overview of HERMES results on measurements of hard exclusive electroproduction of real photons and mesons on hydrogen and deuterium targets is presented. Experimental measurements of hard exclusive processes are commonly described within the formalism of generalized parton distributions (GPDs), which provide a unified description of the structure of hadrons embedding longitudinal-momentum distributions (ordinary PDFs) and transverse-position information (form factors). The HERMES experiment at DESY Hamburg studies hard exclusive processes using polarized electron or positron beams from HERA and internal gas targets. Information about GPDs is gained from the measurements of asymmetries that appear in the azimuthal distributions of produced mesons and photons, together with studies of the azimuthal distribution of the decay products via spin-density matrix elements.

  4. Overview of HERMES Results on Exclusive Processes

    Directory of Open Access Journals (Sweden)

    Movsisyan Aram

    2015-01-01

    Full Text Available An overview of HERMES results on measurements of hard exclusive electroproduction of real photons and mesons on hydrogen and deuterium targets is presented. Experimental measurements of hard exclusive processes are commonly described within the formalism of generalized parton distributions (GPDs, which provide a unified description of the structure of hadrons embedding longitudinal-momentum distributions (ordinary PDFs and transverse-position information (form factors. The HERMES experiment at DESY Hamburg studies hard exclusive processes using polarized electron or positron beams from HERA and internal gas targets. Information about GPDs is gained from the measurements of asymmetries that appear in the azimuthal distributions of produced mesons and photons, together with studies of the azimuthal distribution of the decay products via spin-density matrix elements.

  5. Facilitated exclusion process and Pfaffian Schur processes

    OpenAIRE

    Baik, Jinho; Barraquand, Guillaume; Corwin, Ivan; Suidan, Toufic

    2016-01-01

    We study the Facilitated TASEP, an interacting particle system on the one dimensional integer lattice. We prove that starting from step initial condition, the position of the rightmost particle has Tracy Widom GSE statistics on a cube root time scale, while the statistics in the bulk of the rarefaction fan are GUE. This uses a mapping with last-passage percolation in a half-quadrant, which we study using the formalism of Pfaffian Schur processes. For the model with exponential weights, we pro...

  6. Asymptotic behaviour of exclusive processes in QCD

    International Nuclear Information System (INIS)

    The main ideas, methods and results in the investigation of the asymptotic behaviour of exclusive processes are reviewed. We discuss power behaviour and its dependence on hadron quantum numbers, logarithmic corrections and properties of nonperturbative hadronic wave functions. Applications to meson and baryon form factors, strong, electromagnetic and weak decays of heavy mesons, elastic scattering, threshold behaviour of inclusive structure functions, etc., are described. Comparison of theoretical predictions with experimental data is made whenever possible. The review may be of interest to theoreticians, experimentalists and students specializing in elementary particle physics. The experts in this field can also find new results (nonleading logarithms, higher twist processes, novel applications, etc.). (orig.)

  7. Inhomogeneous Generalization of a Multispecies Totally Asymmetric Zero Range Process

    Science.gov (United States)

    Kuniba, Atsuo; Maruyama, Shouya; Okado, Masato

    2016-06-01

    The n-species totally asymmetric zero range process (n-TAZRP) on a one-dimensional periodic chain studied recently by the authors is a continuous time Markov process where arbitrary number of particles can occupy the same sites and hop to the adjacent sites only in one direction with a priority constraint according to their species. In this paper we introduce an n-parameter generalization of the n-TAZRP having inhomogeneous transition rate. The steady state probability is obtained in a matrix product form and also by an algorithm related to combinatorial R.

  8. Death to perturbative QCD in exclusive processes?

    Energy Technology Data Exchange (ETDEWEB)

    Eckardt, R.; Hansper, J.; Gari, M.F. [Institut fuer Theoretische Physik, Bochum (Germany)

    1994-04-01

    The authors discuss the question of whether perturbative QCD is applicable in calculations of exclusive processes at available momentum transfers. They show that the currently used method of determining hadronic quark distribution amplitudes from QCD sum rules yields wave functions which are completely undetermined because the polynomial expansion diverges. Because of the indeterminacy of the wave functions no statement can be made at present as to whether perturbative QCD is valid. The authors emphasize the necessity of a rigorous discussion of the subject and the importance of experimental data in the range of interest.

  9. Asymmetric processing of durational differences - electrophysiological investigations in Bengali.

    Science.gov (United States)

    Roberts, Adam C; Kotzor, Sandra; Wetterlin, Allison; Lahiri, Aditi

    2014-05-01

    Duration is used contrastively in many languages to distinguish word meaning (e.g. in Bengali, [pata] 'leaf' vs. [pat:a] 'whereabouts'). While there is a large body of research on other contrasts in speech perception (e.g. vowel contrasts and consonantal place features), little work has been done on how durational information is used in speech processing. In non-linguistic studies of low-level processing, such as visual and non-linguistic acoustic pop-out tasks, an asymmetry is found where additional information is more readily detected than missing information. In this study, event-related potentials were recorded during two cross-modal auditory-visual semantic priming studies, where nonword mispronunciations of spoken prime words were created by changing the duration of a medial consonant (real word [dana] 'seed'>nonword [dan:a]). N400 amplitudes showed an opposite asymmetric pattern of results, where increases in consonantal duration were tolerated and led to priming of the visual target, but decreases in consonantal duration were not accepted. This asymmetrical pattern of acceptability is attributed to the fact that a longer consonant includes all essential information for the recognition of the original word with a short medial consonant (a possible default category) and any additional information can be ignored. However, when a consonant is shortened, it lacks the required durational information to activate the word with the original long consonant. PMID:24726333

  10. Comment on "Generalized exclusion processes: Transport coefficients"

    Science.gov (United States)

    Becker, T.; Nelissen, K.; Cleuren, B.; Partoens, B.; Van den Broeck, C.

    2016-04-01

    In a recent paper, Arita et al. [Phys. Rev. E 90, 052108 (2014), 10.1103/PhysRevE.90.052108] consider the transport properties of a class of generalized exclusion processes. Analytical expressions for the transport-diffusion coefficient are derived by ignoring correlations. It is claimed that these expressions become exact in the hydrodynamic limit. In this Comment, we point out that (i) the influence of correlations upon the diffusion does not vanish in the hydrodynamic limit, and (ii) the expressions for the self- and transport diffusion derived by Arita et al. are special cases of results derived in Becker et al. [Phys. Rev. Lett. 111, 110601 (2013), 10.1103/PhysRevLett.111.110601].

  11. Condensation and transport in the totally asymmetric inclusion process (TASIP)

    Science.gov (United States)

    Knebel, Johannes; Weber, Markus F.; Krueger, Torben; Frey, Erwin

    Transport phenomena are often modeled by the hopping of particles on regular lattices or networks. Such models describe, e.g., the exclusive movement of molecular motors along microtubules: no two motors may occupy the same site. In our work, we study inclusion processes that are the bosonic analogues of the fermionic exclusion processes. In inclusion processes, many particles may occupy a single site and hopping rates depend linearly on the occupation of departure and arrival sites. Particles thus attract other particles to their own site. Condensation occurs when particles collectively cluster in one or multiple sites, whereas other sites become depleted.We showed that inclusion processes describe both the selection of strategies in evolutionary zero-sum games and the condensation of non-interacting bosons into multiple quantum states in driven-dissipative systems. The condensation is captured by the antisymmetric Lotka-Volterra equation (ALVE), which constitutes a nonlinearly coupled dynamical system. We derived an algebraic method to analyze the ALVE and to determine the condensates. Our approach allows for the design of networks that result in condensates with oscillating occupations, and yields insight into the interplay between network topology and transport properties. Deutsche Forschungsgemeinschaft (SFB-TR12), German Excellence Initiative (Nanosystems Initiative Munich), Center for NanoScience Munich.

  12. kT factorization of exclusive processes

    Science.gov (United States)

    Nagashima, Makiko; Li, Hsiang-Nan

    2003-02-01

    We prove the kT factorization theorem in perturbative QCD (PQCD) for exclusive processes by considering πγ*→γ(π) and B→γ(π)lν¯. The relevant form factors are expressed as the convolution of hard amplitudes with two-parton meson wave functions in the impact parameter b space, b being conjugate to the parton transverse momenta kT. The point is that on-shell valence partons carry longitudinal momenta initially, and acquire kT through collinear gluon exchanges. The b-dependent two-parton wave functions with an appropriate path for the Wilson links are gauge-invariant. The hard amplitudes, defined as the difference between the parton-level diagrams of on-shell external particles and their collinear approximation, are also gauge-invariant. We compare the predictions for two-body nonleptonic B meson decays derived from kT factorization (the PQCD approach) and from collinear factorization (the QCD factorization approach).

  13. Diffractive and Exclusive Processes at CMS

    CERN Document Server

    Kuznetsova, Ekaterina

    2014-01-01

    We present an overview of the CMS results on diffractive and exclusive production.Measurements of inclusive single and double diffractive production are discussedas well as measurements of the diffractive production at a hard scale. Measurementsof charged particle multiplicities for single diffractive enhanced data sample and studies of central diffractive jet production were perfrmed in a collaboration with the TOTEM experiment. CMS results on cross section measurements for exclusive dilepton and WW production are also presented.

  14. Two-Photon Exclusive Processes in QCD

    OpenAIRE

    Brodsky, Stanley J.

    2000-01-01

    Exclusive two-photon reactions such as Compton scattering at large angles, deeply virtual Compton scattering, and hadron production in photon-photon collisions provide important tests of QCD at the amplitude level, particularly as measures of hadron distribution amplitudes and skewed parton distributions.

  15. The transition probability and the probability for the left-most particle's position of the q-totally asymmetric zero range process

    Energy Technology Data Exchange (ETDEWEB)

    Korhonen, Marko [Department of Mathematics and Statistics, University of Helsinki, FIN-00014 (Finland); Lee, Eunghyun [Centre de Recherches Mathématiques (CRM), Université de Montréal, Quebec H3C 3J7 (Canada)

    2014-01-15

    We treat the N-particle zero range process whose jumping rates satisfy a certain condition. This condition is required to use the Bethe ansatz and the resulting model is the q-boson model by Sasamoto and Wadati [“Exact results for one-dimensional totally asymmetric diffusion models,” J. Phys. A 31, 6057–6071 (1998)] or the q-totally asymmetric zero range process (TAZRP) by Borodin and Corwin [“Macdonald processes,” Probab. Theory Relat. Fields (to be published)]. We find the explicit formula of the transition probability of the q-TAZRP via the Bethe ansatz. By using the transition probability we find the probability distribution of the left-most particle's position at time t. To find the probability for the left-most particle's position we find a new identity corresponding to identity for the asymmetric simple exclusion process by Tracy and Widom [“Integral formulas for the asymmetric simple exclusion process,” Commun. Math. Phys. 279, 815–844 (2008)]. For the initial state that all particles occupy a single site, the probability distribution of the left-most particle's position at time t is represented by the contour integral of a determinant.

  16. The transition probability and the probability for the left-most particle's position of the q-totally asymmetric zero range process

    International Nuclear Information System (INIS)

    We treat the N-particle zero range process whose jumping rates satisfy a certain condition. This condition is required to use the Bethe ansatz and the resulting model is the q-boson model by Sasamoto and Wadati [“Exact results for one-dimensional totally asymmetric diffusion models,” J. Phys. A 31, 6057–6071 (1998)] or the q-totally asymmetric zero range process (TAZRP) by Borodin and Corwin [“Macdonald processes,” Probab. Theory Relat. Fields (to be published)]. We find the explicit formula of the transition probability of the q-TAZRP via the Bethe ansatz. By using the transition probability we find the probability distribution of the left-most particle's position at time t. To find the probability for the left-most particle's position we find a new identity corresponding to identity for the asymmetric simple exclusion process by Tracy and Widom [“Integral formulas for the asymmetric simple exclusion process,” Commun. Math. Phys. 279, 815–844 (2008)]. For the initial state that all particles occupy a single site, the probability distribution of the left-most particle's position at time t is represented by the contour integral of a determinant

  17. Static large deviations of boundary driven exclusion processes

    CERN Document Server

    Farfan, Jonathan

    2009-01-01

    We prove that the stationary measure associated to a boundary driven exclusion process in any dimension satisfies a large deviation principle with rate function given by the quasi potential of the Freidlin and Wentzell theory.

  18. When push comes to shove: Exclusion processes with nonlocal consequences

    Science.gov (United States)

    Almet, Axel A.; Pan, Michael; Hughes, Barry D.; Landman, Kerry A.

    2015-11-01

    Stochastic agent-based models are useful for modelling collective movement of biological cells. Lattice-based random walk models of interacting agents where each site can be occupied by at most one agent are called simple exclusion processes. An alternative motility mechanism to simple exclusion is formulated, in which agents are granted more freedom to move under the compromise that interactions are no longer necessarily local. This mechanism is termed shoving. A nonlinear diffusion equation is derived for a single population of shoving agents using mean-field continuum approximations. A continuum model is also derived for a multispecies problem with interacting subpopulations, which either obey the shoving rules or the simple exclusion rules. Numerical solutions of the derived partial differential equations compare well with averaged simulation results for both the single species and multispecies processes in two dimensions, while some issues arise in one dimension for the multispecies case.

  19. The Processes of Inclusion and Exclusion in Physical Education

    DEFF Research Database (Denmark)

    Jensen, Mette Munk; Agergaard, Sine

    2015-01-01

    Existing research on inclusion and exclusion processes in physical education (PE) has particularly focused on exclusion from PE as something being done to students and attributed to specific social categories such as (female) gender, (low) physical skills or (minority) ethnic background....... This article aims to develop a social-relational perspective on inclusion and exclusion processes defined as students’ participation or non-participation in PE interpreted as a community of practice. In so doing, the article examines how students’ experiences of participation and non-participation in PE...... are influenced by complex interactions within the group of students and in negotiations with teachers about the values and practices of PE. The article is based on an embedded single-case study carried out over the course of 6 months through weekly observations of PE classes in a multi-ethnic school, as well...

  20. Exponential decay and ergodicity of completely asymmetric Lévy processes in a finite interval

    OpenAIRE

    Bertoin, Jean

    1997-01-01

    Consider a completely asymmetric Lévy process which has absolutely continuous transition probabilities. We determine the exponential decay parameter $\\rho$ and the quasistationary distribution for the transition probabilities of the Lévy process killed as it exits from a finite interval, prove that the killed process is $\\rho$-positive and specify the $\\rho$-invariant function and measure.

  1. Educing GPDs from Amplitudes of Hard Exclusive Processes

    CERN Document Server

    Polyakov, M V

    2007-01-01

    The dual parametrization of generalized parton distributions (GPDs) is considered in details. We discuss which part of information about hadron structure encoded in GPDs [part of total GPD image] can be restored from the known amplitude of a hard exclusive process. The physics content of this partial image is analyzed.

  2. Reply to "Comment on `Generalized exclusion processes: Transport coefficients' "

    Science.gov (United States)

    Arita, Chikashi; Krapivsky, P. L.; Mallick, Kirone

    2016-07-01

    We reply to the Comment of Becker, Nelissen, Cleuren, Partoens, and Van den Broeck [Phys. Rev. E 93, 046101 (2016), 10.1103/PhysRevE.93.046101] on our article [Arita, Krapivsky, and Mallick, Phys. Rev. E 90, 052108 (2014), 10.1103/PhysRevE.90.052108] about the transport properties of a class of generalized exclusion processes.

  3. Inclusive and Exclusive Compton Processes in Quantum Chromodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Psaker, Ales [Old Dominion Univ., Norfolk, VA (United States)

    2005-12-01

    In our work, we describe two types of Compton processes. As an example of an inclusive process, we consider the high-energy photoproduction of massive muon pairs off the nucleon. We analyze the process in the framework of the QCD parton model, in which the usual parton distributions emerge as a tool to describe the nucleon in terms of quark and gluonic degrees of freedom. To study its exclusive version, a new class of phenomenological functions is required, namely, generalized parton distributions. They can be considered as a generalization of the usual parton distributions measured in deeply inelastic lepton-nucleon scattering. Generalized parton distributions (GPDs) may be observed in hard exclusive reactions such as deeply virtual Compton scattering. We develop an extension of this particular process into the weak interaction sector. We also investigate a possible application of the GPD formalism to wide-angle real Compton scattering.

  4. Inclusive and Exclusive Compton Processes in Quantum Chromodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Ales Psaker

    2005-12-31

    In our work, we describe two types of Compton processes. As an example of an inclusive process, we consider the high-energy photoproduction of massive muon pairs off the nucleon. We analyze the process in the framework of the QCD parton model, in which the usual parton distributions emerge as a tool to describe the nucleon in terms of quark and gluonic degrees of freedom. To study its exclusive version, a new class of phenomenological functions is required, namely, generalized parton distributions. They can be considered as a generalization of the usual parton distributions measured in deeply inelastic lepton-nucleon scattering. Generalized parton distributions (GPDs) may be observed in hard exclusive reactions such as deeply virtual Compton scattering. We develop an extension of this particular process into the weak interaction sector. We also investigate a possible application of the GPD formalism to wide-angle real Compton scattering.

  5. Hydrodynamic limit of symmetric exclusion processes in inhomogeneous media

    CERN Document Server

    Faggionato, A

    2010-01-01

    In \\cite{J} M. Jara has presented a method, reducing the proof of the hydrodynamic limit of symmetric exclusion processes to an homogenization problem, as unified approach to recent works on the field as \\cite{N}, \\cite{F1}, \\cite{F2} and \\cite{FJL}. Although not stated in \\cite{J}, the reduction of the hydrodynamic limit to an homogenization problem was already obtained (in a different way) in \\cite{N}, \\cite{F1}. This alternative and very simple relation between the two problems goes back to an idea of K.\\ Nagy \\cite{N}, is stated in \\cite{F1}[Section B] for exclusion processes on $\\bbZ^d$ and, as stressed in \\cite{F2}, is completely general. The above relation has been applied to \\cite{N}, \\cite{F1}, \\cite{F2} and \\cite{FJL} and could be applied to other symmetric exclusion processes, mentioned in \\cite{J}. In this short note we briefly recall this unified approach in a complete general setting. Finally, we recall how the homogenization problem has been solved in the above previous works.

  6. Asymmetric skew Bessel processes and their applications to finance

    NARCIS (Netherlands)

    M. Decamps; M.J. Goovaerts; W. Schoutens

    2006-01-01

    In this paper, we extend the Harrison and Shepp's construction of the skew Brownian motion (1981) and we obtain a diffusion similar to the two-dimensional Bessel process with speed and scale densities discontinuous at one point. Natural generalizations to multi-dimensional and fractional order Besse

  7. The AdS/QCD Correspondence and Exclusive Processes

    Energy Technology Data Exchange (ETDEWEB)

    Brodsky, Stanley J.; /SLAC /Southern Denmark U., CP3-Origins; de Teramond, Guy F.; /Costa Rica U.; Deur, Alexandre; /Jefferson Lab

    2010-08-25

    The AdS/CFT correspondence between theories in AdS space and conformal field theories in physical space-time provides an analytic, semi-classical, color-confining model for strongly-coupled QCD. The soft-wall AdS/QCD model modified by a positive-sign dilaton metric leads to a remarkable one-parameter description of nonperturbative hadron dynamics at zero quark mass, including a zero-mass pion and a Regge spectrum of linear trajectories with the same slope in orbital angular momentum L and radial quantum number n for both mesons and baryons. One also predicts the form of the non-perturbative effective coupling {alpha}{sub s}{sup AdS}(q) and its {beta}-function which agrees with the effective coupling {alpha}{sub ga} extracted from the Bjorken sum rule. Light-front holography, which connects the fifth-dimensional coordinate of AdS space z to an invariant impact separation variable {zeta}, allows one to compute the analytic form of the frame-independent light-front wavefunctions, the fundamental entities which encode hadron properties as well as decay constants, form factors, deeply virtual Compton scattering, exclusive heavy hadron decays and other exclusive scattering amplitudes. One thus obtains a relativistic description of hadrons in QCD at the amplitude level with dimensional counting for hard exclusive reactions at high momentum transfer. As specific examples we discuss the behavior of the pion and nucleon form factors in the space-like and time-like regions. We also review the phenomenology of exclusive processes including some anomalous empirical results.

  8. Finite Element Analysis of Symmetric and Asymmetric Three-roll Rolling Process

    Directory of Open Access Journals (Sweden)

    Pesin A.

    2015-01-01

    Full Text Available A three-roll process is a significant technique in the production of wire rod, round bars and hexagonal profiles for structural applications. Better mechanical properties of wire rod, round bars and hexagonal profiles can be achieved due to large plastic deformation by the three-roll process. Asymmetric rolling is a novel technique characterised by a kinematic asymmetry linked to the difference in peripheral speed of the rolls, able to introduce additional shear strains through the bar thickness. In order to achieve this, asymmetrical three-roll rolling process was investigated to better control the deformation compared to the conventional three-roll rolling process in a stand with two three-roll calibers located very close to each other. Simulation of round-triangle-triangle pass rolling was performed. FEM simulations were carried out with using software DEFORM 3D. The influence of the friction coefficient and speed asymmetry on the shear strain and material flow was discussed. The results of simulation can be used to optimize the asymmetric three-roll rolling process to improve the mechanical properties of wire rod, round bars and hexagonal profiles.

  9. Process Design for Hot Forging of Asymmetric to Symmetric Rib-web Shaped Steel

    Directory of Open Access Journals (Sweden)

    H. Cho

    2003-01-01

    Full Text Available The process design of hot forging, asymmetric to symmetric rib-web shaped steel, which is used for the turnout of express rails has been studied. Owing to the great difference in shape between the initial billet and the final forged product, it is impossible to hot forge the rail in a single stage operation. Therefore, multi stage forging and also die design for each stage are necessary for the production process. The numerical simulation for hot forging of asymmetric shape to symmetric shape was carried out using commercial FEM code, DEFORMTM-2D. Modification of the design and repeated simulation was carried out on the basis of the simulation results. For comparison with the simulation results, a flow analysis experiment using plasticine was also carried out. The results of the flow analysis experiment showed good agreement with those of the simulation.

  10. Tests of quantum chromodynamics in exclusive e sup + e sup minus and. gamma. gamma. processes

    Energy Technology Data Exchange (ETDEWEB)

    Brodsky, S.J.

    1989-09-01

    This paper discusses the following topics: Factorization theorem for exclusive processes; Electromagnetic form factors of baryons; Suppression of final state interactions; The {gamma}{pi}{sub 0} Transition form factor; Exclusive charmonium decays; The {pi}-{rho} puzzle; Time-like compton processes; Multi-hadron production; Heavy Quark exclusive states and form factor zeros in QCD; Exclusive {gamma}{gamma} reactions; Higher twist effects; and Tauonium and threshold {tau}{sup +}{tau}{sup {minus}} production. 41 refs., 15 figs. (LSP)

  11. Asymmetric neighborhood functions accelerate ordering process of self-organizing maps

    International Nuclear Information System (INIS)

    A self-organizing map (SOM) algorithm can generate a topographic map from a high-dimensional stimulus space to a low-dimensional array of units. Because a topographic map preserves neighborhood relationships between the stimuli, the SOM can be applied to certain types of information processing such as data visualization. During the learning process, however, topological defects frequently emerge in the map. The presence of defects tends to drastically slow down the formation of a globally ordered topographic map. To remove such topological defects, it has been reported that an asymmetric neighborhood function is effective, but only in the simple case of mapping one-dimensional stimuli to a chain of units. In this paper, we demonstrate that even when high-dimensional stimuli are used, the asymmetric neighborhood function is effective for both artificial and real-world data. Our results suggest that applying the asymmetric neighborhood function to the SOM algorithm improves the reliability of the algorithm. In addition, it enables processing of complicated, high-dimensional data by using this algorithm.

  12. Integrable dissipative exclusion process: Correlation functions and physical properties

    Science.gov (United States)

    Crampe, N.; Ragoucy, E.; Rittenberg, V.; Vanicat, M.

    2016-09-01

    We study a one-parameter generalization of the symmetric simple exclusion process on a one-dimensional lattice. In addition to the usual dynamics (where particles can hop with equal rates to the left or to the right with an exclusion constraint), annihilation and creation of pairs can occur. The system is driven out of equilibrium by two reservoirs at the boundaries. In this setting the model is still integrable: it is related to the open XXZ spin chain through a gauge transformation. This allows us to compute the full spectrum of the Markov matrix using Bethe equations. We also show that the stationary state can be expressed in a matrix product form permitting to compute the multipoints correlation functions as well as the mean value of the lattice and the creation-annihilation currents. Finally, the variance of the lattice current is computed for a finite-size system. In the thermodynamic limit, it matches the value obtained from the associated macroscopic fluctuation theory.

  13. Large Deviations for the Boundary Driven Symmetric Simple Exclusion Process

    Energy Technology Data Exchange (ETDEWEB)

    Bertini, L. [Universita di Roma La Sapienza, Dipartimento di Matematica (Italy)], E-mail: bertini@mat.uniroma1.it; De Sole, A. [MIT, Department of Mathematics (United States)], E-mail: desole@alum.mit.edu; Gabrielli, D. [Universita di Roma La Sapienza, Dipartimento di Matematica (Italy)], E-mail: gabriell@univaq.it; Jona-Lasinio, G. [Universita di Roma La Sapienza, Dipartimento di Fisica and INFN (Italy)], E-mail: jona@roma1.infn.it; Landim, C. [IMPA (Brazil)], E-mail: landim@impa.br

    2003-08-15

    The large deviation properties of equilibrium (reversible) lattice gases are mathematically reasonably well understood. Much less is known in nonequilibrium, namely for nonreversible systems. In this paper we consider a simple example of a nonequilibrium situation, the symmetric simple exclusion process in which we let the system exchange particles with the boundaries at two different rates. We prove a dynamical large deviation principle for the empirical density which describes the probability of fluctuations from the solutions of the hydrodynamic equation. The so-called quasi potential, which measures the cost of a fluctuation from the stationary state, is then defined by a variational problem for the dynamical large deviation rate function. By characterizing the optimal path, we prove that the quasi potential can also be obtained from a static variational problem introduced by Derrida, Lebowitz, and Speer.

  14. Productivity Gap and Asymmetric Trade Relations: The Canada-United States of America Integration Process

    Directory of Open Access Journals (Sweden)

    Germán H. Gonzalez

    2014-08-01

    Full Text Available The usefulness of the European model of integration is currently subject to debate and the North American integration process has been largely ignored as a comparative framework. The asymmetrical relationship between Canada and the United States began a long time before NAFTA, and the study of this process could shed light on the usual problems faced by Latin American countries. This article attempts to encourage discussion about this topic. Particularly,there is evidence for a substantial and positive change in Canadian productivity at the time of the Canada-US Free Trade Agreement (CUFTA. However, the enactment of the North American Free Trade Agreement (NAFTA does not seem to have had the same effect as the earlier treaty.

  15. Microstructures and mechanical properties of commercial purity iron processed by asymmetric rolling

    International Nuclear Information System (INIS)

    For the purpose of grain refinement, commercial purity iron processed by asymmetric rolling (ASR) has been studied by optical microscopy, electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM). Equiaxed ultra fined grains with a grain size of about 0.9 μm and a large fraction of high angle grain boundaries were obtained. The formation of the equiaxed grains is suggested to result from the additional shear strain which is observed by the shape change of a Cu band inserted into the rolled materials. The rolled iron exhibits high yield strength with a low work hardening ability and high microhardness, which are attributed to the high dislocation density and the large fraction of the high angle boundaries.

  16. Process for fabricating PBI hollow fiber asymmetric membranes for gas separation and liquid separation

    Energy Technology Data Exchange (ETDEWEB)

    Jayaweera, Indira; Krishnan, Gopala N.; Sanjurjo, Angel; Jayaweera, Palitha; Bhamidi, Srinivas

    2016-04-26

    The invention provides methods for preparing an asymmetric hollow fiber, the asymmetric hollow fibers prepared by such methods, and uses of the asymmetric hollow fibers. One method involves passing a polymeric solution through an outer annular orifice of a tube-in-orifice spinneret, passing a bore fluid though an inner tube of the spinneret, dropping the polymeric solution and bore fluid through an atmosphere over a dropping distance, and quenching the polymeric solution and bore fluid in a bath to form an asymmetric hollow fiber.

  17. The State University, Due Process and Summary Exclusions

    Science.gov (United States)

    Osborn, Earl D.

    1974-01-01

    In Braxton v. Municipal Court, the California Supreme Court upheld a Penal Code statute allowing for the summary exclusion of students from college campuses. The author discusses the need for procedural safeguards and a reevaluation of the judicial treatment of colleges and universities. (Editor)

  18. 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.

  19. 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.

  20. Measurement of diffractive and exclusive processes with the ATLAS detector

    Directory of Open Access Journals (Sweden)

    Gach Grzegorz

    2016-01-01

    Full Text Available The ATLAS Collaboration has carried out a study of diffractive dijet production in proton–proton collisions at a centre-of-mass energy of √s = 7 TeV at the LHC. The data distributions are compared with Monte Carlo models and the rapidity gap survival probability has been estimated in the kinematic region with high diffractive contribution. Prospects for exclusive jet production studies with the forward proton tagging capability of the AFP sub-detector of ATLAS are also discussed. First results based on data taken jointly with the ATLAS and the LHCf detectors in a p+Pb run will also be shown. In addition, the measurement of the cross-section for the exclusive production of di-lepton pairs in pp collisions at √s = 7 TeV is discussed.

  1. Measurement of diffractive and exclusive processes with the ATLAS detector

    Science.gov (United States)

    Gach, Grzegorz

    2016-07-01

    The ATLAS Collaboration has carried out a study of diffractive dijet production in proton-proton collisions at a centre-of-mass energy of √s = 7 TeV at the LHC. The data distributions are compared with Monte Carlo models and the rapidity gap survival probability has been estimated in the kinematic region with high diffractive contribution. Prospects for exclusive jet production studies with the forward proton tagging capability of the AFP sub-detector of ATLAS are also discussed. First results based on data taken jointly with the ATLAS and the LHCf detectors in a p+Pb run will also be shown. In addition, the measurement of the cross-section for the exclusive production of di-lepton pairs in pp collisions at √s = 7 TeV is discussed.

  2. Measurement of diffractive and exclusive processes with the ATLAS detector

    CERN Document Server

    Gach, Grzegorz; The ATLAS collaboration

    2015-01-01

    The ATLAS collaboration has carried out a study diffractive dijet production at 7 TeV pp collisions at the LHC, i.e. events with a hadronic system containing at least two jets in addition to a large region of pseudorapidity devoid of hadronic activity. The data distributions are compared with Monte Carlo models and the rapidity gap survival probability has been estimated in the kinematic region with high diffractive contribution. Prospects for exclusive jet production studies with the forward proton tagging capability of the AFP sub-detector of ATLAS will be discussed. A first look at data taken jointly with the ATLAS and LHCf detectors in a p+Pb run will also be shown. In addition the measurement of the exclusive $\\gamma+\\gamma \\rightarrow ll$ production cross-section in proton-proton collisions at a centre-of-mass energy of 7 TeV has been carried out.

  3. Exclusive processes at JLab at 6 GeV

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Andrey [Univ. of Connecticut, Storrs, CT (United States); Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

    2015-01-01

    Deeply virtual exclusive reactions provide a unique opportunity to probe the complex internal structure of the nucleon. They allow to access information about the correlations between parton transverse spatial and longitudinal momentum distributions from experimental observables. Dedicated experiments to study Deeply Virtual Compton Scattering (DVCS) and Deeply Virtual Meson Production (DVMP) have been carried out at Jefferson Lab using continuous electron beam with energies up to 6 GeV. Unpolarized cross sections, beam, target and double spin asymmetries have been measured for DVCS as well as for π0 exclusive electroproduction. The data from Hall B provide a wide kinematic coverage with Q2=1-4.5 GeV2, xB=0.1-0.5, and -t up to 2 GeV2. Hall A data have limited kinematic range partially overlapping with Hall B kinematics but provide a high accuracy measurements. Scaling tests of the DVCS cross sections provide solid evidence of twist-2 dominance, which makes chiral-even GPDs accessible even at modest Q2. We will discuss the interpretation of these data in terms of Generalized Parton Distributions (GPDs) model. Successful description of the recent CLAS π0 exclusive production data within the framework of the GPD-based model provides a unique opportunity to access the chiral-odd GPDs.

  4. Exclusive processes at JLab at 6 GeV

    Directory of Open Access Journals (Sweden)

    Kim Andrey

    2015-01-01

    Full Text Available Deeply virtual exclusive reactions provide a unique opportunity to probe the complex internal structure of the nucleon. They allow to access information about the correlations between parton transverse spatial and longitudinal momentum distributions from experimental observables. Dedicated experiments to study Deeply Virtual Compton Scattering (DVCS and Deeply Virtual Meson Production (DVMP have been carried out at Jefferson Lab using continuous electron beam with energies up to 6 GeV. Unpolarized cross sections, beam, target and double spin asymmetries have been measured for DVCS as well as for π0 exclusive electroproduction. The data from Hall B provide a wide kinematic coverage with Q2=1-4.5 GeV2, xB=0.1-0.5, and −t up to 2 GeV2. Hall A data have limited kinematic range partially overlapping with Hall B kinematics but provide a high accuracy measurements. Scaling tests of the DVCS cross sections provide solid evidence of twist-2 dominance, which makes chiral-even GPDs accessible even at modest Q2. We will discuss the interpretation of these data in terms of Generalized Parton Distributions (GPDs model. Successful description of the recent CLAS π0 exclusive production data within the framework of the GPD-based model provides a unique opportunity to access the chiral-odd GPDs.

  5. Equilibrium fluctuations for gradient exclusion processes with conductances in random environments

    CERN Document Server

    Farfan, Jonathan; Valentim, Fabio J

    2009-01-01

    We study the equilibrium fluctuations for a gradient exclusion process with conductances in random environments, which can be viewed as a central limit theorem for the empirical distribution of particles when the system starts from an equilibrium measure.

  6. FRACTIONAL FICK'S LAW FOR THE BOUNDARY DRIVEN EXCLUSION PROCESS WITH LONG JUMPS

    OpenAIRE

    Bernardin, Cédric; Oviedo Jimenez, Byron

    2016-01-01

    A fractional Fick's law and fractional hydrostatics for the one dimensional exclusion process with long jumps in contact with infinite reservoirs at different densities on the left and on the right are derived.

  7. Exclusion in a priority queue

    International Nuclear Information System (INIS)

    We introduce the prioritising exclusion process, a stochastic scheduling mechanism for a priority queueing system in which high priority customers gain advantage by overtaking low priority customers. The model is analogous to a totally asymmetric exclusion process with a dynamically varying lattice length. We calculate exact local density profiles for an unbounded queue by deriving domain wall dynamics from the microscopic transition rules. The structure of the unbounded queue carries over to bounded queues where, although no longer exact, we find the domain wall theory is in very good agreement with simulation results. Within this approximation we calculate average waiting times for queueing customers. (paper)

  8. Deeply Virtual Exclusive Processes and Generalized Parton Distributions

    Energy Technology Data Exchange (ETDEWEB)

    ,

    2011-06-01

    The goal of the comprehensive program in Deeply Virtual Exclusive Scattering at Jefferson Laboratory is to create transverse spatial images of quarks and gluons as a function of their longitudinal momentum fraction in the proton, the neutron, and in nuclei. These functions are the Generalized Parton Distributions (GPDs) of the target nucleus. Cross section measurements of the Deeply Virtual Compton Scattering (DVCS) reaction ep {yields} ep{gamma} in Hall A support the QCD factorization of the scattering amplitude for Q^2 {>=} 2 GeV^2. Quasi-free neutron-DVCS measurements on the Deuteron indicate sensitivity to the quark angular momentum sum rule. Fully exclusive H(e, e'p{gamma} ) measurements have been made in a wide kinematic range in CLAS with polarized beam, and with both unpolarized and longitudinally polarized targets. Existing models are qualitatively consistent with the JLab data, but there is a clear need for less constrained models. Deeply virtual vector meson production is studied in CLAS. The 12 GeV upgrade will be essential for for these channels. The {rho} and {omega} channels reactions offer the prospect of flavor sensitivity to the quark GPDs, while the {phi}-production channel is dominated by the gluon distribution.

  9. GenEx: A simple generator structure for exclusive processes in high energy collisions

    CERN Document Server

    Kycia, R A; Staszewski, R; Turnau, J

    2014-01-01

    A simple C++ class structure for construction of a Monte Carlo event generators which can produce unweighted events within relativistic phase space is presented. The generator is self-adapting to the provided matrix element and acceptance cuts. The program is designed specially for exclusive processes and includes, as an example of such an application, implementation of the model for exclusive production of meson pairs $pp \\rightarrow p M^+M^- p $ in high energy proton-proton collisions.

  10. Asymmetric processing of a substrate protein in sequential allosteric cycles of AAA+ nanomachines

    Science.gov (United States)

    Kravats, Andrea N.; Tonddast-Navaei, Sam; Bucher, Ryan J.; Stan, George

    2013-09-01

    Essential protein quality control includes mechanisms of substrate protein (SP) unfolding and translocation performed by powerful ring-shaped AAA+ (ATPases associated with various cellular activities) nanomachines. These SP remodeling actions are effected by mechanical forces imparted by AAA+ loops that protrude into the central channel. Sequential intra-ring allosteric motions, which underlie repetitive SP-loop interactions, have been proposed to comprise clockwise (CW), counterclockwise (CCW), or random (R) conformational transitions of individual AAA+ subunits. To probe the effect of these allosteric mechanisms on unfoldase and translocase functions, we perform Langevin dynamics simulations of a coarse-grained model of an all-alpha SP processed by the single-ring ClpY ATPase or by the double-ring p97 ATPase. We find that, in all three allosteric mechanisms, the SP undergoes conformational transitions along a common set of pathways, which reveals that the active work provided by the ClpY machine involves single loop-SP interactions. Nevertheless, the rates and yields of SP unfolding and translocation are controlled by mechanism-dependent loop-SP binding events, as illustrated by faster timescales of SP processing in CW allostery compared with CCW and R allostery. The distinct efficacy of allosteric mechanisms is due to the asymmetric collaboration of adjacent subunits, which involves CW-biased structural motions of AAA+ loops and results in CW-compatible torque applied onto the SP. Additional simulations of mutant ClpY rings, which render a subset of subunits catalytically-defective or reduce their SP binding affinity, reveal that subunit-based conformational transitions play the major role in SP remodeling. Based on these results we predict that the minimally functional AAA+ ring includes three active subunits, only two of which are adjacent.

  11. Analysis of Rolling Pressure in Asymmetrical Rolling Process by Slab Method

    Institute of Scientific and Technical Information of China (English)

    TIAN Yong; GUO Yan-hui; WANG Zhao-dong; WANG Guo-dong

    2009-01-01

    The plane strain asymmetrical rolling was analyzed using slab method. The contact arc was replaced by parabola, and the constant surface friction status was adopted during the analysis. The deformation area was divided into three zones according to the direction of the friction. Then, the three zones were studied, respectively. A rolling force model and a rolling torque model were developed based on the analysis, and they were used to analyze the influence of asymmetrical rolling factors on deformation area and unit pressure if they had good precision which was determined by comparing the calculated results with the measured ones.

  12. Novel Phases and Finite-Size Scaling in Two-Species Asymmetric Diffusive Processes

    OpenAIRE

    Leung, Kwan-tai

    1994-01-01

    We study a stochastic lattice gas of particles undergoing asymmetric diffusion in two dimensions. Transitions between a low-density uniform phase and high-density non-uniform phases characterized by localized or extended structure are found. We develop a mean-field theory which relates coarse-grained parameters to microscopic ones. Detailed predictions for finite-size ($L$) scaling and density profiles agree excellently with simulations. Unusual large-$L$ behavior of the transition point para...

  13. Production of mesons with any internal orbital angular momentum in exclusive hard processes

    Energy Technology Data Exchange (ETDEWEB)

    Ichola, A.; Houra-Yaou, L.; Kessler, P.; Parisi, J. [College de France, 75 - Paris (France). Lab. de Physique Corpusculaire

    1994-12-31

    In this paper we present an extension of the computation of exclusive hard processes to the production of (qq) mesons with any orbital angular momentum, as well as of (gg) mesons (``glueballs``). We explicitly compute two examples: tensor-meson par production and glueball plus pion production, both in {gamma} {gamma} collisions. (authors). 16 refs., 7 figs., 1 tab.

  14. [Female students in internships in Parisian hospitals (1871-1910). Exclusion and inclusion processes].

    Science.gov (United States)

    José, María; Somavilla, Ruiz

    2016-01-01

    This study addresses the explicit and implicit exclusion mechanisms that limited the access of women to internships in Paris hospitals during the last decades of the 19th century through examination of the documentation generated in the admission process and the texts of female physicians who supported their access. In response to the applications of female medical students to register for the admission tests, the Conseil de Surveillance de l'Assistance Publique delayed their entry for some years until their registration was finally permitted. However, their inclusion in the institution did not produce integration because of the multiple dimensions of the exclusion mechanisms.

  15. Exclusive diffractive processes in electron-ion collisions

    OpenAIRE

    Toll, Tobias; Ullrich, Thomas

    2012-01-01

    We present a new technique to calculate the cross-section for diffractive vector meson production and DVCS in electron-ion collisions based on the dipole model. The measurement of these processes can provide valuable information on non-linear QCD phenomena, such as gluon saturation, and is the the only known way to gain insight into the spatial distribution of gluons in nuclei. We present predictions of differential cross-section distribution $d\\sigma/dQ^2$ and $d\\sigma/dt$ for $J/\\psi$ and $...

  16. Effects of social exclusion on cognitive processes: anticipated aloneness reduces intelligent thought.

    Science.gov (United States)

    Baumeister, Roy F; Twenge, Jean M; Nuss, Christopher K

    2002-10-01

    Three studies examined the effects of randomly assigned messages of social exclusion. In all 3 studies, significant and large decrements in intelligent thought (including IQ and Graduate Record Examination test performance) were found among people told they were likely to end up alone in life. The decline in cognitive performance was found in complex cognitive tasks such as effortful logic and reasoning; simple information processing remained intact despite the social exclusion. The effects were specific to social exclusion, as participants who received predictions of future nonsocial misfortunes (accidents and injuries) performed well on the cognitive tests. The cognitive impairments appeared to involve reductions in both speed (effort) and accuracy. The effect was not mediated by mood. PMID:12374437

  17. Inclusion and exclusion processes in teacher trainees' professional practice

    DEFF Research Database (Denmark)

    Elle, Birgitte

    between the teacher training college, the trainee jobs and the learning processes of the students. The results of the study are important for rethinking teacher education, but also for future discussions on the possible directions for the renewal of university colleges. It contributes to an understanding......, which become visible as the study relates to some of actual economic, cultural, and politically powerful discourses in Denmark. Thematization and de-naturalization of established cultural, economical, and politically powerful discourses and connections are important, as part of a teacher education.......In the autumn of 2009, a new initiative and way of thinking about teacher education started on a small scale in Denmark. This new Danish initiative consisted of a simultaneous trainee employment at a school, and maintaining the study activities at the teacher education college. This initiative...

  18. Effective ergodicity breaking in an exclusion process with varying system length

    Science.gov (United States)

    Schultens, Christoph; Schadschneider, Andreas; Arita, Chikashi

    2015-09-01

    Stochastic processes of interacting particles in systems with varying length are relevant e.g. for several biological applications. We try to explore what kind of new physical effects one can expect in such systems. As an example, we extend the exclusive queueing process that can be viewed as a one-dimensional exclusion process with varying length, by introducing Langmuir kinetics. This process can be interpreted as an effective model for a queue that interacts with other queues by allowing incoming and leaving of customers in the bulk. We find surprising indications for breaking of ergodicity in a certain parameter regime, where the asymptotic growth behavior depends on the initial length. We show that a random walk with site-dependent hopping probabilities exhibits qualitatively the same behavior.

  19. Processus d'exclusion asymétrique: Effet du désordre, Grandes déviations et fluctuations

    OpenAIRE

    Enaud, Camille

    2005-01-01

    This thesis presents a series of works dealing with the open asymmetric exclusion process.In a first part, we give numerical evidences showing that the position of the first order phase transition in the totally asymmetric exclusion process become sample-dependent when quenched, sitewise disorder is added to the jump rates. These numerical simulations are compared with analytic prediction based on a mean field approach. In a second part, we study the macroscopic properties of the density prof...

  20. The Impact of Social Class on Parent-Professional Interaction in School Exclusion Processes: Deficit or Disadvantage?

    Science.gov (United States)

    Gazeley, Louise

    2012-01-01

    Although a great deal of previous literature has explored the ways in which social class affects parental engagement in educational processes, there has been surprisingly little discussion of the way in which social class shapes the parent-professional interaction that occurs in school exclusion processes specifically. School exclusion processes…

  1. Effects of serotonin 2A/1A receptor stimulation on social exclusion processing

    Science.gov (United States)

    Preller, Katrin H.; Pokorny, Thomas; Hock, Andreas; Kraehenmann, Rainer; Stämpfli, Philipp; Seifritz, Erich; Scheidegger, Milan; Vollenweider, Franz X.

    2016-01-01

    Social ties are crucial for physical and mental health. However, psychiatric patients frequently encounter social rejection. Moreover, an increased reactivity to social exclusion influences the development, progression, and treatment of various psychiatric disorders. Nevertheless, the neuromodulatory substrates of rejection experiences are largely unknown. The preferential serotonin (5-HT) 2A/1A receptor agonist, psilocybin (Psi), reduces the processing of negative stimuli, but whether 5-HT2A/1A receptor stimulation modulates the processing of negative social interactions remains unclear. Therefore, this double-blind, randomized, counterbalanced, cross-over study assessed the neural response to social exclusion after the acute administration of Psi (0.215 mg/kg) or placebo (Pla) in 21 healthy volunteers by using functional magnetic resonance imaging (fMRI) and resting-state magnetic resonance spectroscopy (MRS). Participants reported a reduced feeling of social exclusion after Psi vs. Pla administration, and the neural response to social exclusion was decreased in the dorsal anterior cingulate cortex (dACC) and the middle frontal gyrus, key regions for social pain processing. The reduced neural response in the dACC was significantly correlated with Psi-induced changes in self-processing and decreased aspartate (Asp) content. In conclusion, 5-HT2A/1A receptor stimulation with psilocybin seems to reduce social pain processing in association with changes in self-experience. These findings may be relevant to the normalization of negative social interaction processing in psychiatric disorders characterized by increased rejection sensitivity. The current results also emphasize the importance of 5-HT2A/1A receptor subtypes and the Asp system in the control of social functioning, and as prospective targets in the treatment of sociocognitive impairments in psychiatric illnesses. PMID:27091970

  2. Test practice and processes of in- and exclusion in school classes

    DEFF Research Database (Denmark)

    Andreasen, Karen Egedal

    and drawing on the theory of Etienne Wenger (1998) about communities of practice this paper will discuss the impact from testing on processes of in- and exclusion. The empirical study is ethnographically inspired and includes observations, interviews, documents etc. The analysis shows that even it is framed...... "as" Disability. In: Anthropology & Education Quarterly, Vol. 26, No. 3. Wenger, E. (1998). Communities of Practice: Learning, Meaning, and Identity. Cambridge University Press....

  3. Monitoring surface processes during heterogeneous asymmetric hydrogenation of ketones on a chirally modified platinum catalyst by operando spectroscopy.

    Science.gov (United States)

    Meemken, Fabian; Hungerbühler, Konrad; Baiker, Alfons

    2014-08-11

    Surface processes occurring at the catalytic chiral surface of a cinchona-modified Pt catalyst during the asymmetric hydrogenation of activated ketones have been monitored for the first time using operando ATR-IR spectroscopy. Fundamental information about this catalytic system could be gained, including the chiral modification process of the catalyst, the surface interaction of reactant ketone with preadsorbed chiral modifier, the role of hydrogen as well as the influence of the product enantiomers in the catalytic cycle. The formation of a diastereomeric transient surface complex between ketone and chiral modifier was found to be related to the ketone consumption. Among the studied activated ketones, a correlation between stereoselection and the strength of the intermolecular hydrogen bond was identified. Dissociated hydrogen from the catalytic surface is found to play a crucial role in the formation of the diastereomeric surface complex. PMID:24777839

  4. Pain Processing after Social Exclusion and Its Relation to Rejection Sensitivity in Borderline Personality Disorder.

    Directory of Open Access Journals (Sweden)

    Melanie Bungert

    Full Text Available There is a general agreement that physical pain serves as an alarm signal for the prevention of and reaction to physical harm. It has recently been hypothesized that "social pain," as induced by social rejection or abandonment, may rely on comparable, phylogenetically old brain structures. As plausible as this theory may sound, scientific evidence for this idea is sparse. This study therefore attempts to link both types of pain directly. We studied patients with borderline personality disorder (BPD because BPD is characterized by opposing alterations in physical and social pain; hyposensitivity to physical pain is associated with hypersensitivity to social pain, as indicated by an enhanced rejection sensitivity.Twenty unmedicated female BPD patients and 20 healthy participants (HC, matched for age and education played a virtual ball-tossing game (cyberball, with the conditions for exclusion, inclusion, and a control condition with predefined game rules. Each cyberball block was followed by a temperature stimulus (with a subjective pain intensity of 60% in half the cases. The cerebral responses were measured by functional magnetic resonance imaging. The Adult Rejection Sensitivity Questionnaire was used to assess rejection sensitivity.Higher temperature heat stimuli had to be applied to BPD patients relative to HCs to reach a comparable subjective experience of painfulness in both groups, which suggested a general hyposensitivity to pain in BPD patients. Social exclusion led to a subjectively reported hypersensitivity to physical pain in both groups that was accompanied by an enhanced activation in the anterior insula and the thalamus. In BPD, physical pain processing after exclusion was additionally linked to enhanced posterior insula activation. After inclusion, BPD patients showed reduced amygdala activation during pain in comparison with HC. In BPD patients, higher rejection sensitivity was associated with lower activation differences during

  5. Exclusive $J/\\psi$ process tamed to probe the low $x$ gluon

    CERN Document Server

    Jones, S P; Ryskin, M G; Teubner, T

    2016-01-01

    We address the question as to whether data for J/\\psi mesons produced exclusively in the forward direction at the LHC can be used in global parton analyses (based on collinear factorization) to pin down the low x gluon PDF. We show that it may be possible to overcome the problems that (i) the process is described by a skewed or Generalized Parton Distribution (GPD), (ii) it is very sensitive to the choice of factorization scale and (iii) there is bad LO, NLO,... perturbative stability to the predictions. However, we start by briefly explaining how the alternative k_T factorization approach has been used to describe the process.

  6. Analysis on Shear Deformation for High Manganese Austenite Steel during Hot Asymmetrical Rolling Process Using Finite Element Method

    Institute of Scientific and Technical Information of China (English)

    Feng-li SUI; Xin WANG; Jun ZHAO; Biao MA; Chang-sheng LI

    2015-01-01

    Based on the rigid-plastic ifnite element method (FEM), the shear stress ifeld of deformation region for high manganese austenite steel during hot asymmetrical rolling process was analyzed. The inlfuences of rolling parameters, such as thevelocity ratio of upper to lower rolls, theinitial temperature of workpiece and the reduction rate, on the shear deformation of three nodes in the upper, center and lower layers were discussed. As the rolling parameters change, distinct shear deformation appears in the up-per and lower layers, but the shear deformation in the center layer appears only when the velocity ratio is more than 1.00, and the absolute value of the shear stress in this layer is changed with rolling parameters. A mathematical model which relfected the change of the maximal absolute shear stress for the center layer was established, by which the maximal absolute shear stress for the center layer can be easily calculated and the appropriate rolling technology can be designed.

  7. Scaling of cross-sections for asymmetric (, 3) process on helium-like ions by fast electrons

    Indian Academy of Sciences (India)

    M K Srivastava

    2004-11-01

    An approximate simple scaling law is obtained for asymmetric (, 3) process on helium-like ions for double ionization by fast electrons. It is based on the equation $(Z'^{3} /)$ exp$[−Z' (r_{1} + r_{2})]$, $Z' = Z − (5/16)$ for ground state wave function of helium- like ions and $Z'^{2}$ scaling of energies. The scaling law is found to work very well if the lower energy electron is ejected along the momentum transfer direction and the other one is ejected in the opposite direction. It also works quite well if this electron is ejected within about 90° of the momentum transfer direction with the other electron going in the opposite direction. The scaling law becomes increasingly accurate as the target nuclear charge and the energy increase.

  8. Regulatory issues associated with exclusion, exemption, and clearance related to the mining and minerals processing industries

    International Nuclear Information System (INIS)

    The concepts of exclusion, exemption and clearance have been established in international recommendations and, standards for radiation protection and the management of radioactive waste in recent years. The consistent application of these concepts has given rise to various problems in different spheres of use. This is particularly the case in the mining and minerals processing industries dealing with materials exhibiting elevated concentrations of naturally occurring radionuclides. This paper takes the South African mining industry as an example and highlights some of the issues that have arisen in applying these concepts within a regulatory control regime. (author)

  9. Cube Root Fluctuations for the Corner Growth Model Associated to the Exclusion Process

    OpenAIRE

    Balazs, Marton; Cator, Eric; Seppalainen, Timo

    2006-01-01

    We study the last-passage growth model on the planar integer lattice with exponential weights. With boundary conditions that represent the equilibrium exclusion process as seen from a particle right after its jump we prove that the variance of the last-passage time in a characteristic direction is of order $t^{2/3}$. With more general boundary conditions that include the rarefaction fan case we show that the last-passage time fluctuations are still of order $t^{1/3}$, and also that the transv...

  10. Studies of semi-inclusive and hard exclusive processes at Jlab

    International Nuclear Information System (INIS)

    The main goal of experiments proposed for the CLAS12 detector in conjunction with the 12-GeV CEBAF accelerator is the study of the nucleon through hard exclusive, semi-inclusive, and inclusive processes. This will provide new insights into nucleon dynamics at the elementary quark and gluon level. In this contribution we provide an overview of ongoing studies of the structure of nucleon in terms of quark and gluon degrees of freedom and future physics program planned with CLAS and CLAS12

  11. Studies of semi-inclusive and hard exclusive processes at Jlab

    Energy Technology Data Exchange (ETDEWEB)

    Harutyun Avagyan

    2008-06-19

    The main goal of experiments proposed for the {\\tt CLAS12} detector in conjunction with the 12-GeV CEBAF accelerator is the study of the nucleon through hard exclusive, semi-inclusive, and inclusive processes. This will provide new insights into nucleon dynamics at the elementary quark and gluon level. In this contribution we provide an overview of ongoing studies of the structure of nucleon in terms of quark and gluon degrees of freedom and future physics program planned with CLAS and {\\tt CLAS12}.

  12. Law of large numbers for a transient random walk driven by a symmetric exclusion process

    CERN Document Server

    Avena, Luca; Völlering, Florian

    2011-01-01

    We consider a one-dimensional simple symmetric exclusion process in equilibrium, constituting a dynamic random environment for a nearest-neighbor random walk that on occupied/vacant sites has two different local drifts to the right. We prove that the random walk has an a.s. positive constant global speed by using a regeneration-time argument. This result is part of an ongoing project aiming to analyze the behavior of random walks in slowly mixing dynamic random environments. A brief discussion on this topic is presented.

  13. Process considerations for the asymmetric synthesis of chiral amines using transaminases.

    Science.gov (United States)

    Tufvesson, Pär; Lima-Ramos, Joana; Jensen, Jacob S; Al-Haque, Naweed; Neto, Watson; Woodley, John M

    2011-07-01

    Biocatalytic transamination is being established as key tool for the production of chiral amine pharmaceuticals and precursors due to its excellent enantioselectivity as well as green credentials. Recent examples demonstrate the potential for developing economically competitive processes using a combination of modern biotechnological tools for improving the biocatalyst alongside using process engineering and integrated separation techniques for improving productivities. However, many challenges remain in order for the technology to be more widely applicable, such as technologies for obtaining high yields and productivities when the equilibrium of the desired reaction is unfavorable. This review summarizes both the process challenges and the strategies used to overcome them, and endeavors to describe these and explain their applicability based on physiochemical principles. This article also points to the interaction between the solutions and the need for a process development strategy based on fundamental principles.

  14. On the constituent counting rules for hard exclusive processes involving multiquark states

    CERN Document Server

    Guo, Feng-Kun; Wang, Wei

    2016-01-01

    At high energies, the cross section of a hard exclusive process at finite scattering angle falls off as a negative power of the center-of-mass energy $\\sqrt{s}$. If all involved quark-gluon compositions undergo hard momentum transfers, the scaling of the fall-off is determined by the underlying valence structures of the initial and final states, known as the constituent counting rules. It was argued in the literature that the counting rules are a powerful tool to determine the valence degrees of freedom inside multiquark states when applied to exclusive production processes. However, we demonstrate that for hadrons with hidden flavors the naive application of the constituent counting rules is problematic, since it is not mandatory for all components to participate the hard scattering at the scale $\\sqrt{s}$. The correct scaling rules can be obtained easily by using effective field theory. A few examples involving the $Z_c(3900)^\\pm$ and $X(3872)$ are discussed.

  15. Self-bias Dependence on Process Parameters in Asymmetric Cylindrical Coaxial Capacitively Coupled Plasma

    CERN Document Server

    Upadhyay, J; Popović, S; Valente-Feliciano, A -M; Phillips, L; Vušković, L

    2015-01-01

    An rf coaxial capacitively coupled Ar/Cl2 plasma is applied to processing the inner wall of superconducting radio frequency cavities. A dc self-bias potential is established across the inner electrode sheath due to the surface area difference between inner and outer electrodes of the coaxial plasma. The self-bias potential measurement is used as an indication of the plasma sheath voltage asymmetry. The understanding of the asymmetry in sheath voltage distribution in coaxial plasma is important for the modification of the inner surfaces of three dimensional objects. The plasma sheath voltages were tailored to process the outer wall by providing an additional dc current to the inner electrode with the help of an external dc power supply. The dc self-bias potential is measured for different diameter electrodes and its variation on process parameters such as gas pressure, rf power and percentage of chlorine in the Ar/Cl2 gas mixture is studied. The dc current needed to overcome the self-bias potential to make it ...

  16. Exclusive Processes at Intermediate Energy, Quark-Hadron Duality and the Transition to Perturbative QCD

    CERN Document Server

    Corianò, C; Savkli, C; Coriano, Claudio; Li, Hsiang-nan; Savkli, Cetin

    1998-01-01

    Experiments at CEBAF will scan the intermediate-energy region of the QCD dynamics for the nucleon form factors and for Compton Scattering. These experiments will definitely clarify the role of resummed perturbation theory and of quark-hadron duality (QCD sum rules) in this regime. With this perspective in mind, we review the factorization theorem of perturbative QCD for exclusive processes at intermediate energy scales, which embodies the transverse degrees of freedom of a parton and the Sudakov resummation of the corresponding large logarithms. We concentrate on the pion and proton electromagnetic form factors and on pion Compton scattering. New ingredients, such as the evolution of the pion wave function and the complete two-loop expression of the Sudakov factor, are included. The sensitivity of our predictions to the infrared cutoff for the Sudakov evolution is discussed. We also elaborate on QCD sum rule methods for Compton Scattering, which provide an alternative description of this process. We show that...

  17. Asymmetric function of theta and gamma activity in syllable processing: an intra-cortical study

    Directory of Open Access Journals (Sweden)

    Benjamin eMorillon

    2012-07-01

    Full Text Available Low-gamma (25-45 Hz and theta (4-8 Hz oscillations are proposed to underpin the integration of phonemic and syllabic information, respectively. How these two scales of analysis split functions across hemispheres is unclear. We analyzed cortical responses from an epileptic patient with a rare bilateral electrode implantation (stereotactic EEG in primary (A1/BA41 and A2/BA42 and association auditory cortices (BA22. Using time-frequency analyses, we confirmed the dominance of a 5-6 Hz theta activity in right and of a low-gamma (25-45 Hz activity in left primary auditory cortices (A1/A2, during both resting state and syllable processing. We further detected high-theta (7-8 Hz resting activity in left primary, but also associative auditory regions. In left BA22, its phase correlated with high-gamma induced power. Such a hierarchical relationship across theta and gamma frequency bands (theta/gamma phase-amplitude coupling could index the process by which the neural code shifts from stimulus feature- to phonological- encoding, and is associated with the transition from evoked to induced power responses. These data suggest that theta and gamma activity in right and left auditory cortices bear different functions. They support a scheme where slow parsing of the acoustic information dominates in right-hemisphere at a syllabic (5-6 Hz rate, and left auditory cortex exhibits a more complex cascade of oscillations, reflecting the possible extraction of transient acoustic cues at a fast (~25-45 Hz rate, subsequently integrated at a slower, e.g. syllabic one. Slow oscillations could functionally participate to speech processing by structuring gamma activity in left BA22, where abstract percepts emerge.

  18. Emotional, Cognitive and Self-Enhancement Processes in Aggressive Behavior After Interpersonal Rejection and Exclusion

    Directory of Open Access Journals (Sweden)

    Joanna Rajchert

    2015-11-01

    Full Text Available The relationship between exclusion or rejection and aggression is already well documented, but there is still a debate about the mechanisms that underlie this effect. In two studies we focused on the propensity to react aggressively (readiness for aggression on the bases of emotional, cognitive or self-enhancement (personality-immanent processes. In both studies we first measured readiness for aggression and then ego-depleted participants. Next, in Study 1 we excluded participants (n = 96 using an online ball throwing game and measured displaced aggressive behavior - intensity and duration of an unpleasant noise administrated to a stranger. In Study 2 participants (n = 140 were rejected by a peer on the basis of an interview that they gave and then could retaliate by reducing peer's chance for getting a job. The results show that exclusion effect on displaced aggression was moderated by cognitive readiness for aggression, while rejection effect on retaliatory aggression was shaped by emotional and personality-immanent readiness for aggression as well as ego-depletion. The results were discussed in light of the strength model of self-control by Baumeister, Vohs, and Tice (2007.

  19. Attachment and children's biased attentional processing: evidence for the exclusion of attachment-related information.

    Directory of Open Access Journals (Sweden)

    Eva Vandevivere

    Full Text Available Research in both infants and adults demonstrated that attachment expectations are associated with the attentional processing of attachment-related information. However, this research suffered from methodological issues and has not been validated across ages. Employing a more ecologically valid paradigm to measure attentional processes by virtue of eye tracking, the current study tested the defensive exclusion hypothesis in late childhood. According to this hypothesis, insecurely attached children are assumed to defensively exclude attachment-related information. We hypothesized that securely attached children process attachment- related neutral and emotional information in a more open manner compared to insecurely attached children. Sixty-two children (59.7% girls, 8-12 years completed two different tasks, while eye movements were recorded: task one presented an array of neutral faces including mother and unfamiliar women and task two presented the same with happy and angry faces. Results indicated that more securely attached children looked longer at mother's face regardless of the emotional expression. Also, they tend to have more maintained attention to mother's neutral face. Furthermore, more attachment avoidance was related to a reduced total viewing time of mother's neutral, happy, and angry face. Attachment anxiety was not consistently related to the processing of mother's face. Findings support the theoretical assumption that securely attached children have an open manner of processing all attachment-related information.

  20. The process of coevolutionary competitive exclusion: speciation, multifractality and power-laws in correlation

    CERN Document Server

    Zhu, Chen-Ping; Yang, Hui-Jie; Xiong, Shi-Jie; Gu, Zhi-Ming; Shi, Da-Ning; He, Da-Ren; Wang, Bing-Hong

    2007-01-01

    Competitive exclusion, a key principle of ecology, can be generalized to understand many other complex systems. Individuals under surviving pressure tend to be different from others, and correlations among them change correspondingly to the updating of their states. We show with numerical simulation that these aptitudes can contribute to group formation or speciation in social fields. Moreover, they can lead to power-law topological correlations of complex networks. By coupling updating states of nodes with variation of connections in a network, structural properties with power-laws and functions like multifractality, spontaneous ranking and evolutionary branching of node states can emerge out simultaneously from the present self-organized model of coevolutionary process.

  1. Differential neural processing of social exclusion in adolescents with non-suicidal self-injury: An fMRI study.

    Science.gov (United States)

    Groschwitz, Rebecca C; Plener, Paul L; Groen, Georg; Bonenberger, Martina; Abler, Birgit

    2016-09-30

    Non-suicidal self-injury (NSSI) is highly prevalent in adolescence and has been suggested as an autonomous diagnosis in the Diagnostic and Statistical Manual (DSM-5). Social rejection is as potential risk-factor for NSSI and depression in adolescence. Objectives of this study were to identify differences in neural processing of social rejection in depressed adolescents with and without co-morbid NSSI and healthy controls. Participants were 28 depressed adolescents (14 with co-morbid NSSI, 79% females) and 15 healthy controls, with an average age of 15.2 years (SD=1.8). Social exclusion was implemented using the Cyberball paradigm 'Cyberball' during functional magnetic resonance imaging (fMRI). All participants reported feelings of social exclusion after fMRI scanning. Investigating the effects of NSSI, we found that depressed adolescents with NSSI showed relatively enhanced activation of the medial prefrontal cortex (mPFC) and the ventrolateral prefrontal cortex (vlPFC) compared to depressed adolescents without NSSI and also compared to healthy controls. Results point towards divergent processing of social exclusion in depressed adolescents with NSSI as compared to adolescents with mere depression in brain regions previously related to the processing of social exclusion. This finding of distinct neurophysiological responses may stimulate further research on individual treatment approaches.

  2. Analysis of aliphatic carboxylic acids in anaerobic digestion process waters by ion-exclusion chromatography

    Institute of Scientific and Technical Information of China (English)

    Kazuaki ITO; Kazuhiko TANAKA; Jun SAKAMOTO; Kazuya NAGAOKA; Yohichi TAKAYAMA; Takashi KANAHORI; Hiroshi SUNAHARA; Tsuneo HAYASHI; Shinji SATO; Takeshi HIROKAWA

    2012-01-01

    The analysis of seven aliphatic carboxylic acids ( formic,acetic,propionic,iso-butyric,n-butyric,iso-valeric and n-valeric acid) in anaerobic digestion process waters for biogas production was examined by ion-exclusion chromatography with dilute acidic eluents (benzoic acid,perfluorobutyric acid (PFBA) and sulfuric acid) and non-suppressed conductivity/ultraviolet (UV) detection.The columns used were a styrene/divinylbenzene-based strongly acidic cation-exchange resin column ( TSKgel SCX) and a polymethacrylate-based weakly acidic cation-exchange resin column ( TSKgel Super IC-A/C ).Good separation was performed on the TSKgel SCX in shorter retention times.For the TSKgel Super IC-A/C,peak shape of the acids was sharp and symmetrical in spite of longer retention times.In addition,the mutual separation of the acids was good except for iso- and n-butyric acids.The better separation and good detection was achieved by using the two columns (TSKgel SCX and TSKgel Super IC-A/C connected in series),lower concentrations of PFBA and sulfuric acid as eluents,non-suppressed conductivity detection and UV detection at 210 nm.This analysis was applied to anaerobic digestion process waters.The chromatograms with conductivity detection were relatively simpler compared with those of UV detection.The use of two columns with different selectivities for the aliphatic carboxylic acids and the two detection modes was effective for the determination and identification of the analytes in anaerobic digestion process waters containing complex matrices.

  3. Olefins-selective asymmetric carbon molecular sieve hollow fiber membranes for hybrid membrane-distillation processes for olefin/paraffin separations

    KAUST Repository

    Xu, Liren

    2012-12-01

    In this paper, the development of asymmetric carbon molecular sieve (CMS) hollow fiber membranes and advanced processes for olefin/paraffin separations based on the CMS membranes are reported. Membrane-based olefin/paraffin separations have been pursued extensively over the past decades. CMS membranes are promising to exceed the performance upper bound of polymer materials and have demonstrated excellent stability for gas separations. Previously, a substructure collapse phenomenon was found in Matrimid ® precursor derived CMS fiber. To overcome the permeance loss due to the increased separation layer thickness, 6FDA-DAM and 6FDA/BPDA-DAM precursors were selected as potential new precursors for carbon membrane formation. Defect-free asymmetric 6FDA-DAM and 6FDA/BPDA-DAM hollow fibers were successfully fabricated from a dry-jet/wet-quench spinning process. Polymer rigidity, glass-rubber transition and asymmetric morphology were correlated. CMS hollow fiber membranes produced from 6FDA-polymer precursors showed significant improvement in permeance for ethylene/ethane and propylene/propane separations. Further studies revealed that the CMS membranes are olefins-selective, which means the membranes are able to effectively separate olefins (ethylene and propylene) from paraffins (ethane and propane). This unique feature of CMS materials enables advanced hybrid membrane-distillation process designs. By using the olefins-selective membranes, these new processes may provide advantages over previously proposed retrofitting concepts. Further applications of the membranes are explored for hydrocarbons processes. Significant energy savings and even reduced footprint may be achieved in olefins production units. © 2012 Elsevier B.V.

  4. 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

  5. Asymmetric Ashes

    Science.gov (United States)

    2006-11-01

    Astronomers are reporting remarkable new findings that shed light on a decade-long debate about one kind of supernovae, the explosions that mark a star's final demise: does the star die in a slow burn or with a fast bang? From their observations, the scientists find that the matter ejected by the explosion shows significant peripheral asymmetry but a nearly spherical interior, most likely implying that the explosion finally propagates at supersonic speed. These results are reported today in Science Express, the online version of the research journal Science, by Lifan Wang, Texas A&M University (USA), and colleagues Dietrich Baade and Ferdinando Patat from ESO. "Our results strongly suggest a two-stage explosion process in this type of supernova," comments Wang. "This is an important finding with potential implications in cosmology." ESO PR Photo 44/06 ESO PR Photo 44/06 Clumpy Explosion (Artist's Impression) Using observations of 17 supernovae made over more than 10 years with ESO's Very Large Telescope and the McDonald Observatory's Otto Struve Telescope, astronomers inferred the shape and structure of the debris cloud thrown out from Type Ia supernovae. Such supernovae are thought to be the result of the explosion of a small and dense star - a white dwarf - inside a binary system. As its companion continuously spills matter onto the white dwarf, the white dwarf reaches a critical mass, leading to a fatal instability and the supernova. But what sparks the initial explosion, and how the blast travels through the star have long been thorny issues. The supernovae Wang and his colleagues observed occurred in distant galaxies, and because of the vast cosmic distances could not be studied in detail using conventional imaging techniques, including interferometry. Instead, the team determined the shape of the exploding cocoons by recording the polarisation of the light from the dying stars. Polarimetry relies on the fact that light is composed of electromagnetic waves

  6. Observation of a sequential process in charge-asymmetric dissociation of CO2q + (q =4 ,5 ) upon the impact of highly charged ions

    Science.gov (United States)

    Khan, Arnab; Tribedi, Lokesh C.; Misra, Deepankar

    2015-09-01

    The dynamics involved in three-body breakup of carbon dioxide upon the impact of 1-MeV Ar8 + ions is investigated. Among the six possible fragmentation channels of CO2q + (q =4 ,5 ) , where all fragments are charged, two charge-asymmetric fragmentation channels show evidence of a sequential breakup process. It has been observed that the molecular structures tend towards deformed geometry as the initial charge on the precursor molecular ion increases. The total energy deposition to the system is found to play a key role in deciding between different breakup pathways.

  7. Competitive Exclusion and Axiomatic Set-Theory: De Morgan's Laws, Ecological Virtual Processes, Symmetries and Frozen Diversity.

    Science.gov (United States)

    Flores, J C

    2016-03-01

    This work applies the competitive exclusion principle and the concept of potential competitors as simple axiomatic tools to generalized situations in ecology. These tools enable apparent competition and its dual counterpart to be explicitly evaluated in poorly understood ecological systems. Within this set-theory framework we explore theoretical symmetries and invariances, De Morgan's laws, frozen evolutionary diversity and virtual processes. In particular, we find that the exclusion principle compromises the geometrical growth of the number of species. By theoretical extending this principle, we can describe interspecific depredation in the dual case. This study also briefly considers the debated situation of intraspecific competition. The ecological consequences of our findings are discussed; particularly, the use of our framework to reinterpret coupled mathematical differential equations describing certain ecological processes.

  8. Searching saturation effects in inclusive and exclusive eA processes

    Directory of Open Access Journals (Sweden)

    Goncalves V. P.

    2016-01-01

    Full Text Available The searching of saturation effects in inclusive and exclusive eA collisions is reviewed. In particular, we present a comparison between the linear and non-linear predictions for the nuclear structure functions as well as for the Deep Virtual Compton Scattering and vector meson production in future eA colliders.

  9. Accessing proton generalized parton distributions and pion distribution amplitudes with exclusive pion-induced Drell-Yan process at J-PARC

    CERN Document Server

    Sawada, Takahiro; Kumano, Shunzo; Peng, Jen-Chieh; Sawada, Shinya; Tanaka, Kazuhiro

    2016-01-01

    Generalized parton distributions (GPDs) encoding multi-dimensional information of hadron partonic structure appear as the building blocks in a factorized description of hard exclusive reactions. The nucleon GPDs have been accessed by deeply virtual Compton scattering and deeply virtual meson production with lepton beam. A complementary probe with hadron beam is the exclusive pion-induced Drell-Yan process. In this paper, we discuss recent theoretical advances on describing this process in terms of nucleon GPDs and pion distribution amplitudes. Furthermore, we address the feasibility of measuring the exclusive pion-induced Drell-Yan process $\\pi^- p \\to \\mu^+\\mu^- n$ via a spectrometer at the High Momentum Beamline being constructed at J-PARC in Japan. Realization of such measurement at J-PARC will provide a new test of perturbative QCD descriptions of a novel class of hard exclusive reactions. It will also offer the possibility of experimentally accessing nucleon GPDs at large timelike virtuality.

  10. Relativistic electromagnetic charge response: Finite versus infinite systems, exclusive versus inclusive processes

    International Nuclear Information System (INIS)

    Connections between exclusive and inclusive electron scattering are explored within the framework of the relativistic plane-wave impulse approximation, beginning with an analysis of the model-independent kinematical constraints to be found in the missing-energy - missing-momentum plane. From the interplay between these constraints and the spectral function basic features of the exclusive and inclusive nuclear responses are seen to arise. In particular, the responses of the relativistic Fermi gas and of a specific hybrid model with bound nucleons in the initial state are compared. The latter facilitates extrapolations from light nuclei to very heavy ones where the former model has some validity. As expected, the exclusive responses are significantly different in the two models, whereas the inclusive ones are rather similar. By extending previous work on the relativistic Fermi gas, a reduced response is introduced for the hybrid model such that it fulfills the Coulomb and the higher-power energy-weighted sum rules. Although incorporating specific classes of off-shellness for the struck nucleons, it is found that the reducing factor required is largely model independent and, as such, yields a reduced response that is useful for studies of scaling and of the Coulomb sum rule. In particular, guided by the difference between the energy-weighted sum rules of the two models a new scaling variable appropriate for heavy nuclei is devised. Finally, a version of the relativistic Fermi gas which has zeroth, first, and second energy-weighted moments of the longitudinal response that agree rather well with those of the hybrid model is constructed: this version thus incorporates a priori the binding effects of the struck nucleons while retaining the simplicity of the original Fermi gas and provides the basis for future extensions of the model. copyright 1997 The American Physical Society

  11. The exclusive $J/\\psi$ process at the LHC tamed to probe the low $x$ gluon

    CERN Document Server

    Jones, S P; Ryskin, M G; Teubner, T

    2016-01-01

    The perturbative QCD expansion for $J/\\psi$ photoproduction appears to be unstable: the NLO correction is large (and of opposite sign) to the LO contribution. Moreover, the predictions are very sensitive to the choice of factorization and renormalization scales. Here we show that perturbative stability is greatly improved by imposing a $`Q_0$ cut' on the NLO coefficient functions; a cut which is required to avoid double counting. $Q_0$ is the input scale used in the parton DGLAP evolution. This result opens the possibility of high precision exclusive $J/\\psi$ data in the forward direction at the LHC being able to determine the low $x$ gluon distribution at low scales.

  12. Exclusive $J/\\psi$ Production in Diffractive Process with AdS/QCD Holographic Wave Function in BLFQ

    CERN Document Server

    Xie, Ya-ping; Zhao, Xingbo

    2016-01-01

    The AdS/QCD holographic wave function of basis light-front quantization (BLFQ) for vector meson $J/\\psi$ is applied in this manuscript. The exclusive production of $J/\\psi$ in diffractive process is computed in dipole model with AdS/QCD holographic wave function. We use IP-Sat and IIM model in the calculation of the differential cross section of the dipole scattering off the proton. The prediction of AdS/QCD holographic wave function in BLFQ gives a good agreement to the experimental data.

  13. Asymmetric Parton Distributions

    CERN Document Server

    Radyushkin, A V

    1997-01-01

    Applications of perturbative QCD to hard exclusive electroproduction processes in the Bjorken limit at small invariant momentum transfer t bring in a new type of parton distributions which have hybrid properties, resembling both the parton distribution functions and the distribution amplitudes. Their t-dependence is analogous to that of hadronic form factors. We discuss general properties of these new parton distributions, their relation to usual parton densities and the evolution equations which they satisfy.

  14. 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.

  15. Macroscopic transport equations in many-body systems from microscopic exclusion processes in disordered media: a review

    Directory of Open Access Journals (Sweden)

    Marta Galanti

    2016-08-01

    Full Text Available Describing particle transport at the macroscopic or mesoscopic level in non-ideal environments poses fundamental theoretical challenges in domains ranging from inter and intra-cellular transport in biology to diffusion in porous media. Yet, often the nature of the constraints coming from many-body interactions or reflecting a complex and confining environment are better understood and modeled at the microscopic level.In this paper we review the subtle link between microscopic exclusion processes and the mean-field equations that ensue from them in the continuum limit. We show that in an inhomogeneous medium, i.e. when jumps are controlled by site-dependent hopping rates, one can obtain three different nonlinear advection-diffusion equations in the continuum limit, suitable for describing transport in the presence of quenched disorder and external fields, depending on the particular rule embodying site inequivalence at the microscopic level. In a situation that might be termed point-like scenario, when particles are treated as point-like objects, the effect of crowding as imposed at the microscopic level manifests in the mean-field equations only if some degree of inhomogeneity is enforced into the model. Conversely, when interacting agents are assigned a finite size, under the more realistic extended crowding framework, exclusion constraints persist in the unbiased macroscopic representation.

  16. Transverse Momentum and Sudakov Effects in Exclusive QCD Processes $\\gamma* \\gamma \\pi0$ Form Factor

    CERN Document Server

    Musatov, I V

    1997-01-01

    We analyze effects due to transverse degrees of freedom in QCD calculations of the fundamental hard exclusive amplitude of $\\gamma^*\\gamma \\to \\pi^0$ transition. A detailed discussion is given of the relation between the modified factorization approach (MFA) of Sterman {\\it et al.} and standard factorization (SFA). Working in Feynman gauge, we construct basic building blocks of MFA from the one-loop coefficient function of the SFA, demonstrating that Sudakov effects are distinctly different from higher-twist corrections. We show also that the handbag-type diagram, contrary to naive expectations, does not contain an infinite chain of $(M^2/Q^2)^n$ corrections: they come only from diagrams with transverse gluons emitted from the hard propagator. A simpler picture emerges within the QCD sum rule approach: the sum over soft $\\bar q G \\ldots G q$ Fock components is dual to $\\bar qq$ states generated by the local axial current. We combine the results based on QCD sum rules with pQCD radiative corrections and observ...

  17. Scaling Solution in the Large Population Limit of the General Asymmetric Stochastic Luria-Delbrück Evolution Process

    Science.gov (United States)

    Kessler, David A.; Levine, Herbert

    2015-02-01

    One of the most popular models for quantitatively understanding the emergence of drug resistance both in bacterial colonies and in malignant tumors was introduced long ago by Luria and Delbrück. Here, individual resistant mutants emerge randomly during the birth events of an exponentially growing sensitive population. A most interesting limit of this process occurs when the population size is large and mutation rates are low, but not necessarily small compared to . Here we provide a scaling solution valid in this limit, making contact with the theory of Levy -stable distributions, in particular one discussed long ago by Landau. One consequence of this association is that moments of the distribution are highly misleading as far as characterizing typical behavior. A key insight that enables our solution is that working in the fixed population size ensemble is not the same as working in a fixed time ensemble. Some of our results have been presented previously in abbreviated form [12].

  18. Analytic coupling and Sudakov effects in exclusive processes: pion and γ*γ→π0 form factors

    International Nuclear Information System (INIS)

    We develop and discuss in technical detail an infrared-finite factorization and optimized renormalization scheme for calculating exclusive processes, which enables the inclusion of transverse degrees of freedom without entailing suppression of calculated observables, like form factors. This is achieved by employing an analytic, i.e., infrared stable, running strong-coupling αs(Q2) which removes the Landau singularity at Q2=ΛQCD2 by a minimum power-behaved correction. The ensuing contributions to the cusp anomalous dimension - related to the Sudakov form factor - and to the quark anomalous dimension - which controls evolution - lead to an enhancement at high Q2 of the hard part of exclusive amplitudes, calculated in perturbative QCD, while simultaneously improving its scaling behavior. The phenomenological implications of this framework are analyzed by applying it to the pion's electromagnetic form factor, including the NLO contribution to the hard-scattering amplitude, and also to the pion-photon transition at LO. For the pion wave function, an improved ansatz of the Brodsky-Huang-Lepage type is employed, which includes an effective (constituent-like) quark mass, mq=0.33 GeV. Predictions for both form factors are presented and compared to the experimental data, applying Brodsky-Lepage-Mackenzie commensurate scale setting. We find that the perturbative hard part prevails at momentum transfers above about 20 GeV2, while at lower Q2 values the pion form factor is dominated by Feynman-type contributions. The theoretical prediction for the γ*γ→π0 form factor indicates that the true pion distribution amplitude may be somewhat broader than the asymptotic one. (orig.)

  19. 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.

  20. NLO corrections to $\\chi_{bJ}$ two-body exclusive decay processes

    CERN Document Server

    Chen, Long-Bin

    2014-01-01

    The next-to-leading order QCD corrections for $\\chi_{bJ}$, the p-wave bottomonium, to $J/\\psi$ pair decay processes were evaluated utilizing NRQCD factorization formalism. It was determined that the scale dependence was depressed with NLO corrections, and hence the uncertainties in the leading order results were greatly reduced. The total branch ratios were found to be the order of $10^{-5}$ for all three $\\chi_{bJ}\\rightarrow J/\\psi J/\\psi$ processes,indicating that they were observable in the LHC and super-B experiments.

  1. Analysis of hard exclusive scattering processes of the HERMES recoil experiment

    Energy Technology Data Exchange (ETDEWEB)

    Brodski, Irina

    2014-11-15

    Deeply virtual Compton Scattering (DVCS), ep → epγ is the simplest reaction giving indication of generalized parton distributions (GPD) of the nucleon. The DVCS process has the same final state as the Bethe-Heitler process (BH). For this reason the access is taken not through the cross-sections directly but through asymmetries between DVCS events depending on charge and polarization of the 27.6 GeV beam. For the first time the azimuthal asymmetry amplitudes according the charge of the lepton beam are extracted using a kinematically complete reconstruction method at the HERMES experiment. The recoil detector installed in 2006 allows the reconstruction of recoiling protons that completes the measurements of the forward detector to cover almost the complete angle range around the vertex. This approach allows suppressing the background processes by almost a complete magnitude compared to the traditional method using only the information of the forward spectrometer. The analysis of the asymmetries was carried out at different values of the kinematic variables t{sub c'} x{sub B} and Q{sup 2} to investigate the dependence of these variables. This work pushes the limits of the readability of data and shows which periods have been found to be unstable in the data acquisition. It points out the impact of this finding to previous HERMES publications.

  2. Deficiência e trabalho no setor informal: considerações sobre processos de inclusão e exclusão social Disability and work in the informal sector: consideration of inclusion and exclusion processes

    Directory of Open Access Journals (Sweden)

    Maria Cristina Tissi

    2000-12-01

    Full Text Available Este estudo abordou a condição de trabalho com deficiência no comércio ambulante de São Paulo, enquanto vivência de processos de exclusão e, paradoxalmente, de inclusão social. O trabalho é concebido pelos ambulantes como elemento que proporciona relacionamentos sociais e confere dignidade e respeito na rede de relações das próprias vidas, mas o plano da sociabilidade, porém, mostra-se contraditório. No ponto de vista do processo de trabalho, a atuação no comércio ambulante revela traços de degradação moral e política; a permanência de um esquema de corrupção, a imposição da subordinação, etc., expressam uma exclusão social, mas os vendedores ambulantes com deficiência não podem ser considerados excluídos. É mais apropriado considerar que aproximam-se da zona de vulnerabilidade, caracterizada por Castel pela instabilidade ocupacional e relacionai.This study addressed work conditions and disability in street vendor activity in São Paulo as experience of exclusion processes and, paradoxically, of social inclusion. Work is considered by street vendors the element providing social relationships and dignity and respect in the social network, within strict limits, it also means opportunity for autonomy, decision, management of their own lives. However, as to sociability it is controversial. In respect to work process, street vendor activity shows signs of moral and political degradation. Maintenance of a corruption scheme, imposition of subordination, etc., express social exclusion, but the disabled street vendors could not be considered as excluded. It is more appropriate to consider them as closer to the vulnerability zone, characterized by occupational and relational unstability, according to Castel.

  3. Foot and mouth disease (FMD) virus: quantification of whole virus particles during the vaccine manufacturing process by size exclusion chromatography.

    Science.gov (United States)

    Spitteler, Marcelo A; Fernández, Ignacio; Schabes, Erika; Krimer, Alejandro; Régulier, Emmanuel G; Guinzburg, Mariela; Smitsaart, Eliana; Levy, M Susana

    2011-09-22

    Foot and mouth disease (FMD) is a highly infectious viral disease that affects cattle, sheep, goats and swine causing severe economic losses worldwide. The efficacy of inactivated vaccines is critically dependent on the integrity of foot and mouth disease virus (FMDV) particles. The recommended method to quantify the active ingredient of vaccines is the 140S quantitative sucrose density gradient analysis. This method has been an immensely valuable tool over the past three decades but it is highly operator dependent and difficult to automate. We developed a method to quantify FMDV particles during the vaccine manufacturing process that is based on separation of components by size-exclusion chromatography and measurement of virus by absorption at 254nm. The method is linear in the 5-70μg/mL range, it is applicable to different FMDV strains, and has a good correlation with the 140S test. The proposed method uses standard chromatographic media and it is amenable to automation. The method has potential as a process analytical technology and for control of final product by manufacturers, international vaccine banks and regulatory agencies.

  4. 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

  5. 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.

  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. Exclusive Dealing

    DEFF Research Database (Denmark)

    Fumagalli, Chiara; Motta, Massimo; Rønde, Thomas

    2012-01-01

    This paper studies a model whereby exclusive dealing (ED) can both promote investment and foreclose a more efficient supplier. Since ED promotes the incumbent seller's investment, the seller and the buyer realize a greater surplus from bilateral trade under exclusivity. Hence, the parties involved...

  8. The psychology of exclusivity

    OpenAIRE

    Troy Jollimore

    2008-01-01

    Friendship and romantic love are, by their very nature, exclusive relationships. This paper suggests that we can better understand the nature of the exclusivity in question by understanding what is wrong with the view of practical reasoning I call the Comprehensive Surveyor View. The CSV claims that practical reasoning, in order to be rational, must be a process of choosing the best available alternative from a perspective that is as detached and objective as possible. But this view, while it...

  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. The effects of partial throughfall exclusion on canopy processes, aboveground production, and biogeochemistry of an Amazon forest

    Science.gov (United States)

    Nepstad, D. C.; Moutinho, P.; Dias-Filho, M. B.; Davidson, E.; Cardinot, G.; Markewitz, D.; Figueiredo, R.; Vianna, N.; Chambers, J.; Ray, D.; Guerreiros, J. B.; Lefebvre, P.; Sternberg, L.; Moreira, M.; Barros, L.; Ishida, F. Y.; Tohlver, I.; Belk, E.; Kalif, K.; Schwalbe, K.

    2002-10-01

    Moist tropical forests in Amazonia and elsewhere are subjected to increasingly severe drought episodes through the El Niño-Southern Oscillation (ENSO) and possibly through deforestation-driven reductions in rainfall. The effects of this trend on tropical forest canopy dynamics, emissions of greenhouse gases, and other ecological functions are potentially large but poorly understood. We established a throughfall exclusion experiment in an east-central Amazon forest (Tapajós National Forest, Brazil) to help understand these effects. After 1-year intercalibration period of two 1-ha forest plots, we installed plastic panels and wooden gutters in the understory of one of the plots, thereby excluding ˜890 mm of throughfall during the exclusion period of 2000 (late January to early August) and ˜680 mm thus far in the exclusion period of 2001 (early January to late May). Average daily throughfall reaching the soil during the exclusion period in 2000 was 4.9 and 8.3 mm in the treatment and control plots and was 4.8 and 8.1 mm in 2001, respectively. During the first exclusion period, surface soil water content (0-2 m) declined by ˜100 mm, while deep soil water (2-11 m) was unaffected. During the second exclusion period, which began shortly after the dry season when soil water content was low, surface and deep soil water content declined by ˜140 and 160 mm, respectively. Although this depletion of soil water provoked no detectable increase in leaf drought stress (i.e., no reduction in predawn leaf water potential), photosynthetic capacity declined for some species, the canopy thinned (greater canopy openness and lower leaf area index) during the second exclusion period, stem radial growth of trees litter production) declined by one fourth, from 15.1 to 11.4 Mg ha-1 yr-1, in the treatment plot and decreased slightly, from 11.9 to 11.5 Mg ha-1 yr-1, in the control plot. Stem respiration varied seasonally and was correlated with stem radial growth but showed no treatment

  11. Continuous processing of recombinant proteins: Integration of inclusion body solubilization and refolding using simulated moving bed size exclusion chromatography with buffer recycling.

    Science.gov (United States)

    Wellhoefer, Martin; Sprinzl, Wolfgang; Hahn, Rainer; Jungbauer, Alois

    2013-12-01

    An integrated process which combines continuous inclusion body dissolution with NaOH and continuous matrix-assisted refolding based on closed-loop simulated moving bed size exclusion chromatography was designed and experimentally evaluated at laboratory scale. Inclusion bodies from N(pro) fusion pep6His and N(pro) fusion MCP1 from high cell density fermentation were continuously dissolved with NaOH, filtered and mixed with concentrated refolding buffer prior to refolding by size exclusion chromatography (SEC). This process enabled an isocratic operation of the simulated moving bed (SMB) system with a closed-loop set-up with refolding buffer as the desorbent buffer and buffer recycling by concentrating the raffinate using tangential flow filtration. With this continuous refolding process, we increased the refolding and cleavage yield of both model proteins by 10% compared to batch dilution refolding. Furthermore, more than 99% of the refolding buffer of the raffinate could be recycled which reduced the buffer consumption significantly. Based on the actual refolding data, we compared throughput, productivity, and buffer consumption between two batch dilution refolding processes - one using urea for IB dissolution, the other one using NaOH for IB dissolution - and our continuous refolding process. The higher complexity of the continuous refolding process was rewarded with higher throughput and productivity as well as significantly lower buffer consumption compared to the batch dilution refolding processes.

  12. 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

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. One-transit paths and the steady state of a non-equilibrium process in a discrete-time update

    International Nuclear Information System (INIS)

    We have shown that the partition function of the asymmetric simple exclusion process with open boundaries in a sublattice-parallel updating scheme is equal to that of a two-dimensional one-transit walk model defined on a diagonally rotated square lattice. It has also been shown that the physical quantities defined in these systems are related through a similarity transformation

  18. The Influence of the Asymmetric Arb Process on the Properties of Al-Mg-Al Multi-Layer Sheets / Wpływ Asymetrii W Procesie Arb Na Właściwości Wielowarstwowych Blach Al-Mg-Al

    Directory of Open Access Journals (Sweden)

    Wierzba A.

    2015-12-01

    Full Text Available The paper presents the results of the experimental study of the three-layer Al-Mg-Al sheets rolling process by the ARB method. The tests carried out were limited to single-pass symmetric and asymmetric rolling processes. An Al-Mg-Al package with an initial thickness of 4 mm (1-2-1 mm was subjected to the process of rolling with a relative reduction of 50%. To activate the shear band in the strip being deformed, an asymmetry factor of av=2 was applied. From the test results, an increase in the tensile strength of the multi-layer Al-Mg-Al sheets obtained from the asymmetric process was observed. Microhardness tests did not show any significant differences in aluminium layer between respective layers of sheets obtained from the symmetric and the asymmetric process. By contrast, for the magnesium layer, an increase in microhardness from 72 HV to 79 HV could be observed for the asymmetric rolling. The analysis of the produced Al-Mg-Al sheets shows that the good bond between individual layers and grain refinement in the magnesium layer contributed to the obtaining of higher mechanical properties in the multi-layer sheets produced in the asymmetric process compared to the sheets obtained from the symmetric process.

  19. 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.

  20. 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.

  1. 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....

  2. 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

  3. Measurement of exclusive $\\rho^{+}\\rho^{-}$ production in mid-virtuality two-photon interactions and study of the $\\gamma \\gamma^{*} \\to \\rho\\rho$ process at LEP

    CERN Document Server

    Achard, P; Aguilar-Benítez, M; Alcaraz, J; Alemanni, G; Allaby, James V; Aloisio, A; Alviggi, M G; Anderhub, H; Andreev, V P; Anselmo, F; Arefev, A; Azemoon, T; Aziz, T; Bagnaia, P; Bajo, A; Baksay, G; Baksay, L; Baldew, S V; Banerjee, S; Barczyk, A; Barillère, R; Bartalini, P; Basile, M; Batalova, N; Battiston, R; Bay, A; Becattini, F; Becker, U; Behner, F; Bellucci, L; Berbeco, R; Berdugo, J; Berges, P; Bertucci, B; Betev, B L; Biasini, M; Biglietti, M; Biland, A; Blaising, J J; Blyth, S C; Bobbink, G J; Böhm, A; Boldizsar, L; Borgia, B; Bottai, S; Bourilkov, D; Bourquin, Maurice; Braccini, S; Branson, J G; Brochu, F; Burger, J D; Burger, W J; Cai, X D; Capell, M; Cara Romeo, G; Carlino, G; Cartacci, A; Casaus, J; Cavallari, F; Cavallo, N; Cecchi, C; Cerrada, M; Chamizo-Llatas, M; Chang, Y H; Chemarin, M; Chen, A; Chen, G; Chen, G M; Chen, H F; Chen, H S; Chiefari, G; Cifarelli, Luisa; Cindolo, F; Clare, I; Clare, R; Coignet, G; Colino, N; Costantini, S; de la Cruz, B; Cucciarelli, S; van Dalen, J A; De Asmundis, R; Déglon, P L; Debreczeni, J; Degré, A; Dehmelt, K; Deiters, K; Della Volpe, D; Delmeire, E; Denes, P; De Notaristefani, F; De Salvo, A; Diemoz, M; Dierckxsens, M; Dionisi, C; Dittmar, M; Doria, A; Dova, M T; Duchesneau, D; Duda, M; Echenard, B; Eline, A; El-Hage, A; El-Mamouni, H; Engler, A; Eppling, F J; Extermann, P; Falagán, M A; Falciano, S; Favara, A; Fay, J; Fedin, O; Felcini, M; Ferguson, T; Fesefeldt, H S; Fiandrini, E; Field, J H; Filthaut, F; Fisher, P H; Fisher, W; Fisk, I; Forconi, G; Freudenreich, Klaus; Furetta, C; Galaktionov, Yu; Ganguli, S N; García-Abia, P; Gataullin, M; Gentile, S; Giagu, S; Gong, Z F; Grenier, G; Grimm, O; Grünewald, M W; Guida, M; Gupta, V K; Gurtu, A; Gutay, L J; Haas, D; Hatzifotiadou, D; Hebbeker, T; Hervé, A; Hirschfelder, J; Hofer, H; Hohlmann, M; Holzner, G; Hou, S R; Hu, Y; Jin, B N; Jones, L W; de Jong, P; Josa-Mutuberria, I; Kaur, M; Kienzle-Focacci, M N; Kim, J K; Kirkby, Jasper; Kittel, E W; Klimentov, A; König, A C; Kopal, M; Koutsenko, V F; Kraber, M; Krämer, R W; Krüger, A; Kunin, A; Ladrón de Guevara, P; Laktineh, I; Landi, G; Lebeau, M; Lebedev, A; Lebrun, P; Lecomte, P; Lecoq, P; Le Coultre, P; Le Goff, J M; Leiste, R; Levtchenko, M; Levchenko, P M; Li, C; Likhoded, S; Lin, C H; Lin, W T; Linde, Frank L; Lista, L; Liu, Z A; Lohmann, W; Longo, E; Lü, Y S; Luci, C; Luminari, L; Lustermann, W; Ma Wen Gan; Malgeri, L; Malinin, A; Maña, C; Mans, J; Martin, J P; Marzano, F; Mazumdar, K; McNeil, R R; Mele, S; Merola, L; Meschini, M; Metzger, W J; Mihul, A; Milcent, H; Mirabelli, G; Mnich, J; Mohanty, G B; Muanza, G S; Muijs, A J M; Musicar, B; Musy, M; Nagy, S; Natale, S; Napolitano, M; Nessi-Tedaldi, F; Newman, H; Nisati, A; Novák, T; Nowak, H; Ofierzynski, R A; Organtini, G; Pal, I; Palomares, C; Paolucci, P; Paramatti, R; Passaleva, G; Patricelli, S; Paul, T; Pauluzzi, M; Paus, C; Pauss, Felicitas; Pedace, M; Pensotti, S; Perret-Gallix, D; Petersen, B; Piccolo, D; Pierella, F; Pioppi, M; Piroué, P A; Pistolesi, E; Plyaskin, V; Pohl, M; Pozhidaev, V; Pothier, J; Prokofev, D; Prokofiev, D O; Quartieri, J; Rahal-Callot, G; Rahaman, M A; Raics, P; Raja, N; Ramelli, R; Rancoita, P G; Ranieri, R; Raspereza, A V; Razis, P; Ren, D; Rescigno, M; Reucroft, S; Riemann, S; Riles, K; Roe, B P; Romero, L; Rosca, A; Rosemann, C; Rosenbleck, C; Rosier-Lees, S; Roth, S; Rubio, J A; Ruggiero, G; Rykaczewski, H; Sakharov, A; Saremi, S; Sarkar, S; Salicio, J; Sánchez, E; Schäfer, C; Shchegelskii, V; Schopper, Herwig Franz; Schotanus, D J; Sciacca, C; Servoli, L; Shevchenko, S; Shivarov, N; Shoutko, V; Shumilov, E; Shvorob, A; Son, D; Souga, C; Spillantini, P; Steuer, M; Stickland, D P; Stoyanov, B; Strässner, A; Sudhakar, K; Sultanov, G G; Sun, L Z; Sushkov, S; Suter, H; Swain, J D; Szillási, Z; Tang, X W; Tarjan, P; Tauscher, L; Taylor, L; Tellili, B; Teyssier, D; Timmermans, C; Ting, Samuel C C; Ting, S M; Tonwar, S C; Tóth, J; Tully, C; Tung, K L; Ulbricht, J; Valente, E; Van de Walle, R T; Vásquez, R; Veszpremi, V; Vesztergombi, G; Vetlitskii, I; Vicinanza, D; Viertel, Gert M; Villa, S; Vivargent, M; Vlachos, S; Vodopyanov, I; Vogel, H; Vogt, H; Vorobev, I; Vorobyov, A A; Wadhwa, M; Wang, Q; Wang, X L; Wang, Z M; Weber, M; Wilkens, H; Wynhoff, S; Xia, L; Xu, Z Z; Yamamoto, J; Yang, B Z; Yang, C G; Yang, H J; Yang, M; Yeh, S C; Zalite, A; Zalite, Yu; Zhang, Z P; Zhao, J; Zhu, G Y; Zhu, R Y; Zhuang, H L; Zichichi, A; Zimmermann, B; Zöller, M

    2005-01-01

    Exclusive rho+rho- production in two-photon collisions between a quasi-real photon, gamma, and a mid-virtuality photon, gamma*, is studied with data collected at LEP at centre-of-mass energies root(s)=183-209GeV with a total integrated luminosity of 684.8pb^-1. The cross section of the gamma gamma* -> rho+ rho- process is determined as a function of the photon virtuality, Q^2, and the two-photon centre-of-mass energy, W_gg, in the kinematic region: 0.2GeV^2 rho rho process over the Q^2-region 0.2GeV^2 < Q^2 < 30 GeV^2.

  4. Social and Health Care Access for the Physically Disabled in 19th Century French-Speaking Switzerland : A Double Process of Exclusion and Integration

    Directory of Open Access Journals (Sweden)

    Kaba, Mariama

    2007-07-01

    Full Text Available During the 19th century, an unprecedented process of medicalisation and institutionalisation took place in Europe. The parallel development of urbanised and industrialised areas furthered the densification of a network of care institutions such as infirmaries and dispensaries, whilst medical tourism was developed among the upper classes stimulating the founding of new private clinics. A more institutional kind of care structure for people suffering from a disability also emerged. This medical and/or social care structure was part of a process of integration or exclusion, according to whether the disabled person’s state of health was likely to improve or not. This paper will focus on physically disabled persons, who were vaguely referred to as invalids or as “incurable” in 19th century institutional documents. Being mainly interested in French-speaking Switzerland, I will present the access to social and health care in the cantons of Geneva, Vaud and Neuchâtel.

  5. 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)

  6. Exclusive Dijet production from CDF2LHC

    Energy Technology Data Exchange (ETDEWEB)

    Gallinaro, Michele; /Rockefeller U.

    2005-04-01

    Exclusive dijet production at the Tevatron can be used as a benchmark to establish predictions on exclusive diffractive Higgs production, a process with a much smaller cross section. Exclusive dijet production in Double Pomeron Exchange processes, including diffractive Higgs production with measurements at the Tevatron and predictions for the Large Hadron Collider are presented. Using new data from the Tevatron and dedicated diffractive triggers, no excess over a smooth falling distribution for exclusive dijet events could be found. Upper limits on the exclusive dijet production cross section are presented and compared to current theoretical predictions.

  7. 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

  8. 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.

  9. 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.

  10. 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...

  11. 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,...

  12. Collective Dynamics on a Two-Lane Asymmetrically Coupled TASEP with Mutually Interactive Langmuir Kinetics

    Science.gov (United States)

    Gupta, Arvind Kumar

    2016-03-01

    Motivated by the recent experimental observations on clustering of motor proteins on microtubule filament, we study an open system of two parallel totally asymmetric simple exclusion processes under asymmetric coupling conditions, which incorporates the mutual interaction with the surrounding environment through Langmuir Kinetics (LK) in both the lanes. In the modified LK, the attachment and detachment rates depends on the configuration of nearest neighboring sites. We analyse the model within the framework of continuum mean-field theory and the phase diagrams along with density profiles are obtained using boundary layer analysis. The effect of mutual interactions on the phase diagram for two different situations of attachment and detachment (LK) rates is discussed. Under the symmetric LK dynamics, the topological structure of the phase diagram remains similar to the one in without mutual interaction; while for the antisymmetric case, after a certain critical value of attractive/repulsive mutual attraction, significant changes are found in the qualitative nature of phase diagram. Moreover, it is shown that the type of mutual interaction affects the dynamic properties of motor proteins. The theoretical findings are examined by extensive Monte-Carlo simulations.

  13. The asymmetric alkylation of dimethylhydrazones; intermolecular chirality transfer using sparteine as chiral ligand.

    Science.gov (United States)

    McSweeney, Christina M; Foley, Vera M; McGlacken, Gerard P

    2014-12-01

    The asymmetric alkylation of ketones represents a fundamental transformation in organic chemistry. Chiral auxiliaries have been used almost exclusively for this transformation. Herein we describe a strategy for the generation of enantiomerically enriched α-alkylated ketones up to an er of 83 : 17, using a chiral ligand protocol.

  14. Characterization of enzymatically synthesized amylopectin analogs via asymmetrical flow field flow fractionation

    NARCIS (Netherlands)

    Ciric, Jelena; Rolland-Sabate, Agnes; Guilois, Sophie; Loos, Katja

    2014-01-01

    Asymmetrical flow field flow fractionation (AF4), when coupled with multi-angle laser light scattering (MALLS), is a very powerful technique for determination of the macromolecular structure of high molar mass (branched) polysaccharides. AF4 is a size fractionation technique just as size exclusion c

  15. 40 CFR 261.39 - Conditional Exclusion for Used, Broken Cathode Ray Tubes (CRTs) and Processed CRT Glass...

    Science.gov (United States)

    2010-07-01

    ... complete until any such claim is resolved in accordance with 40 CFR 260.2. (v) The export of CRTs is... CFR part 266, subpart C instead of the requirements of this section. ... Cathode Ray Tubes (CRTs) and Processed CRT Glass Undergoing Recycling. 261.39 Section 261.39 Protection...

  16. 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...

  17. 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.

  18. 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...

  19. 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

  20. 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.

  1. 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...

  2. Polarization dependent switching of asymmetric nanorings with a circular field

    Directory of Open Access Journals (Sweden)

    Nihar R. Pradhan

    2016-01-01

    Full Text Available We experimentally investigated the switching from onion to vortex states in asymmetric cobalt nanorings by an applied circular field. An in-plane field is applied along the symmetric or asymmetric axis of the ring to establish domain walls (DWs with symmetric or asymmetric polarization. A circular field is then applied to switch from the onion state to the vortex state, moving the DWs in the process. The asymmetry of the ring leads to different switching fields depending on the location of the DWs and direction of applied field. For polarization along the asymmetric axis, the field required to move the DWs to the narrow side of the ring is smaller than the field required to move the DWs to the larger side of the ring. For polarization along the symmetric axis, establishing one DW in the narrow side and one on the wide side, the field required to switch to the vortex state is an intermediate value.

  3. 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

  4. Exclusive dimuon production with LHCb

    CERN Multimedia

    Shears, Tara

    2011-01-01

    We report on studies of exclusive dimuon production using LHCb experimental data. Exclusively produced muon pairs can be produced by two photon fusion (a QED process ideally suited to obtaining a precise integrated luminosity measure), or through resonances produced by pomeron-photon fusion or double pomeron exchange.We present cross-section measurements for exclusive dimuon production, and the first observations at a proton-proton collider of exclusive J/psi, psi’ and chi_c states, obtained with 37 pb-1 of data at centre of mass energy of 7 TeV. The resolution of the LHCb detectors allow the chic0, chic1 and chic2 states to be separated. We compare our results to theoretical predictions.

  5. Continuous processing of recombinant proteins: integration of refolding and purification using simulated moving bed size-exclusion chromatography with buffer recycling.

    Science.gov (United States)

    Wellhoefer, Martin; Sprinzl, Wolfgang; Hahn, Rainer; Jungbauer, Alois

    2014-04-11

    Continuous processing of recombinant proteins was accomplished by combining continuous matrix-assisted refolding and purification by tandem simulated moving bed (SMB) size-exclusion chromatography (SEC). Recombinant proteins, N(pro) fusion proteins from inclusion bodies were dissolved with NaOH and refolded in the SMB system with a closed-loop set-up with refolding buffer as the desorbent buffer and buffer recycling of the refolding buffer of the raffinate by tangential flow filtration. For further purification of the refolded proteins, a second SMB operation also based on SEC was added. The whole system could be operated isocratically with refolding buffer as the desorbent buffer, and buffer recycling could also be applied in the purification step. Thus, a significant reduction in buffer consumption was achieved. The system was evaluated with two proteins, the N(pro) fusion pep6His and N(pro) fusion MCP-1. Refolding solution, which contained residual N(pro) fusion peptide, the cleaved autoprotease N(pro), and the cleaved target peptide was used as feed solution. Full separation of the cleaved target peptide from residual proteins was achieved at a purity and recovery in the raffinate and extract, respectively, of approximately 100%. In addition, more than 99% of the refolding buffer of the raffinate was recycled. A comparison of throughput, productivity, and buffer consumption of the integrated continuous process with two batch processes demonstrated that up to 60-fold higher throughput, up to 180-fold higher productivity, and at least 28-fold lower buffer consumption can be obtained by the integrated continuous process, which compensates for the higher complexity.

  6. 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.

  7. The transition probability and the probability for the left-most particle's position of the q-totally asymmetric zero range process

    OpenAIRE

    Korhonen, Marko; Lee, Eunghyun

    2014-01-01

    We treat the $N$-particle ZRP whose jumping rates satisfy a certain condition. This condition is required to use the Bethe ansatz and the resulting model is the $q$-boson model that appeared in [J. Phys. A, \\textbf{31} 6057--6071 (1998)] by Sasamoto and Wadati or the $q$-TAZRP in \\textit{MacDonald processes} by Borodin and Corwin. We find the explicit formula of the transition probability of the $q$-TAZRP via the Bethe ansatz. By using the transition probability we find the probability distri...

  8. Formation of hexagonal boron nitride nanoscrolls induced by inclusion and exclusion of self-assembling molecules in solution process.

    Science.gov (United States)

    Hwang, Da Young; Suh, Dong Hack

    2014-06-01

    Unlike nanoscrolls of 2D graphene, those of 2D h-BN have not been demonstrated, except for only a few experimental reports. Nanoscrolls of h-BN with high yields and reproducibility are first synthesized by a simple solution process. Inner-tube diameters of BNSs including LCAs, N-(2-aminoethyl)-3α-hydroxy-5β-cholan-24-amide, a bile acid derivative and self-assembling material, can be controlled by adjusting the diameter of the LCA fiber which is grown by self-assembly. TEM and SEM images show that BNSs have a tube-like morphology and the inner-tube diameter of BNSs can be controlled in the range from 20 to 60 nm for a smaller diameter, up to 300 nm for a larger diameter by LCA fiber growth inside the BNSs. Finally, open cylindrical BNSs with hollow cores were obtained by dissolving LCAs inside BNSs.

  9. QED radiative effects in the processes of exclusive photon electroproduction from polarized protons with the next-to-leading accuracy

    Energy Technology Data Exchange (ETDEWEB)

    Akushevich, Igor V. [Duke University, JLAB; Ilyichev, Alexander [Byelorussian State University; Shumeiko, Nikolai M [Byelorussian State University

    2014-08-01

    Radiative effects in the electroproduction of photons in polarized ep-scattering are calculated with the next-to-leading (NLO) accuracy. The contributions of loops and two photon emission were presented in analytical form. The covariant approach of Bardin and Shumeiko was used to extract the infrared divergence. All contributions to the radiative correction were presented in the form of the correction to the leptonic tensor thus allowing for further applications in other experiments, e.g., deep inelastic scattering. The radiative corrections (RC) to the cross sections and polarization asymmetries were analyzed numerically for kinematical conditions of the current measurement at Jefferson Lab. Specific attention was paid on analyzing kinematical conditions for the process with large radiative effect when momenta of two photons in the final state are collinear to momenta of initial and final electrons, respectively.

  10. Listening to an audio drama activates two processing networks, one for all sounds, another exclusively for speech.

    Directory of Open Access Journals (Sweden)

    Robert Boldt

    Full Text Available Earlier studies have shown considerable intersubject synchronization of brain activity when subjects watch the same movie or listen to the same story. Here we investigated the across-subjects similarity of brain responses to speech and non-speech sounds in a continuous audio drama designed for blind people. Thirteen healthy adults listened for ∼19 min to the audio drama while their brain activity was measured with 3 T functional magnetic resonance imaging (fMRI. An intersubject-correlation (ISC map, computed across the whole experiment to assess the stimulus-driven extrinsic brain network, indicated statistically significant ISC in temporal, frontal and parietal cortices, cingulate cortex, and amygdala. Group-level independent component (IC analysis was used to parcel out the brain signals into functionally coupled networks, and the dependence of the ICs on external stimuli was tested by comparing them with the ISC map. This procedure revealed four extrinsic ICs of which two-covering non-overlapping areas of the auditory cortex-were modulated by both speech and non-speech sounds. The two other extrinsic ICs, one left-hemisphere-lateralized and the other right-hemisphere-lateralized, were speech-related and comprised the superior and middle temporal gyri, temporal poles, and the left angular and inferior orbital gyri. In areas of low ISC four ICs that were defined intrinsic fluctuated similarly as the time-courses of either the speech-sound-related or all-sounds-related extrinsic ICs. These ICs included the superior temporal gyrus, the anterior insula, and the frontal, parietal and midline occipital cortices. Taken together, substantial intersubject synchronization of cortical activity was observed in subjects listening to an audio drama, with results suggesting that speech is processed in two separate networks, one dedicated to the processing of speech sounds and the other to both speech and non-speech sounds.

  11. Formation of hexagonal boron nitride nanoscrolls induced by inclusion and exclusion of self-assembling molecules in solution process

    Science.gov (United States)

    Hwang, Da Young; Suh, Dong Hack

    2014-05-01

    Unlike nanoscrolls of 2D graphene, those of 2D h-BN have not been demonstrated, except for only a few experimental reports. Nanoscrolls of h-BN with high yields and reproducibility are first synthesized by a simple solution process. Inner-tube diameters of BNSs including LCAs, N-(2-aminoethyl)-3α-hydroxy-5β-cholan-24-amide, a bile acid derivative and self-assembling material, can be controlled by adjusting the diameter of the LCA fiber which is grown by self-assembly. TEM and SEM images show that BNSs have a tube-like morphology and the inner-tube diameter of BNSs can be controlled in the range from 20 to 60 nm for a smaller diameter, up to 300 nm for a larger diameter by LCA fiber growth inside the BNSs. Finally, open cylindrical BNSs with hollow cores were obtained by dissolving LCAs inside BNSs.Unlike nanoscrolls of 2D graphene, those of 2D h-BN have not been demonstrated, except for only a few experimental reports. Nanoscrolls of h-BN with high yields and reproducibility are first synthesized by a simple solution process. Inner-tube diameters of BNSs including LCAs, N-(2-aminoethyl)-3α-hydroxy-5β-cholan-24-amide, a bile acid derivative and self-assembling material, can be controlled by adjusting the diameter of the LCA fiber which is grown by self-assembly. TEM and SEM images show that BNSs have a tube-like morphology and the inner-tube diameter of BNSs can be controlled in the range from 20 to 60 nm for a smaller diameter, up to 300 nm for a larger diameter by LCA fiber growth inside the BNSs. Finally, open cylindrical BNSs with hollow cores were obtained by dissolving LCAs inside BNSs. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr00897a

  12. Generation of central exclusive final states

    CERN Document Server

    Lönnblad, Leif

    2016-01-01

    We present a scheme for the generation of central exclusive final states in the Pythia 8 program. The implementation allows for the investigation of higher order corrections to such exclusive processes as approximated by the initial-state parton shower in Pythia 8. To achieve this, the spin and colour decomposition of the initial-state shower has been worked out, in order to determine the probability that a partonic state generated from an inclusive sub-process followed by a series of initial-state parton splittings can be considered as an approximation of an exclusive colour- and spin-singlet process. We use our implementation to investigate effects of parton showers on some examples of central exclusive processes, and find sizeable effects on di-jet production, while the effects on e.g. central exclusive Higgs production are minor.

  13. Hard exclusive pion leptoproduction

    CERN Document Server

    Kroll, Peter

    2016-01-01

    In this talk it is reported on an analysis of hard exclusive leptoproduction of pions within the handbag approach. It is argued that recent measurements of this process performed by HERMES and CLAS clearly indicate the occurrence of strong contributions from transversely polarized photons. Within the handbag approach such gamma*_T -> pi transitions are described by the transversity GPDs accompanied by twist-3 pion wave functions. It is shown that the handbag approach leads to results on cross sections and single-spin asymmetries in fair agreement with experiment. Predictions for other pseudoscalar meson channels are also briefly discussed.8 pages

  14. 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.

  15. Interaction of toluene with two-color asymmetric laser fields: Controlling the directional emission of molecular hydrogen fragments

    International Nuclear Information System (INIS)

    The interaction of toluene with strong asymmetric two-color laser irradiation of 40 fs duration is studied by means of Time of flight mass spectrometry. Highly energetic H2+ and H3+ fragment ions are produced through an isomerization process taking place within transient multiply charged parent ions. Comparative study of deuterium labeled toluene isotopes enables the discrimination between molecular hydrogen fragments formed exclusively within the CH3- part from those that require hydrogen atom exchange between the former and the phenyl moiety. It is demonstrated that by manipulating the relative phase of the ω/2ω field components the selective ionization of oriented toluene molecules can be used as a tool to control the directional emission of the H2+, H3+ species

  16. 42 CFR 402.308 - Waivers of exclusions.

    Science.gov (United States)

    2010-10-01

    ... waiver of exclusion requests. CMS processes a request for a waiver of exclusion as follows: (1) Notifies... authorization to obtain information from private health insurers, peer review organizations (including, but...

  17. 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...

  18. 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)

  19. 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...

  20. 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...

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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…

  7. Experimental Quantification of Asymmetric Einstein-Podolsky-Rosen Steering.

    Science.gov (United States)

    Sun, Kai; Ye, Xiang-Jun; Xu, Jin-Shi; Xu, Xiao-Ye; Tang, Jian-Shun; Wu, Yu-Chun; Chen, Jing-Ling; Li, Chuan-Feng; Guo, Guang-Can

    2016-04-22

    Einstein-Podolsky-Rosen (EPR) steering describes the ability of one observer to nonlocally "steer" the other observer's state through local measurements. EPR steering exhibits a unique asymmetric property; i.e., the steerability can differ between observers, which can lead to one-way EPR steering in which only one observer obtains steerability in the steering process. This property is inherently different from the symmetric concepts of entanglement and Bell nonlocality, and it has attracted increasing interest. Here, we experimentally demonstrate asymmetric EPR steering for a class of two-qubit states in the case of two measurement settings. We propose a practical method to quantify the steerability. We then provide a necessary and sufficient condition for EPR steering and clearly demonstrate one-way EPR steering. Our work provides new insight into the fundamental asymmetry of quantum nonlocality and has potential applications in asymmetric quantum information processing. PMID:27152778

  8. Experimental Quantification of Asymmetric Einstein-Podolsky-Rosen Steering.

    Science.gov (United States)

    Sun, Kai; Ye, Xiang-Jun; Xu, Jin-Shi; Xu, Xiao-Ye; Tang, Jian-Shun; Wu, Yu-Chun; Chen, Jing-Ling; Li, Chuan-Feng; Guo, Guang-Can

    2016-04-22

    Einstein-Podolsky-Rosen (EPR) steering describes the ability of one observer to nonlocally "steer" the other observer's state through local measurements. EPR steering exhibits a unique asymmetric property; i.e., the steerability can differ between observers, which can lead to one-way EPR steering in which only one observer obtains steerability in the steering process. This property is inherently different from the symmetric concepts of entanglement and Bell nonlocality, and it has attracted increasing interest. Here, we experimentally demonstrate asymmetric EPR steering for a class of two-qubit states in the case of two measurement settings. We propose a practical method to quantify the steerability. We then provide a necessary and sufficient condition for EPR steering and clearly demonstrate one-way EPR steering. Our work provides new insight into the fundamental asymmetry of quantum nonlocality and has potential applications in asymmetric quantum information processing.

  9. 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....

  10. Neurons derive from the more apical daughter in asymmetric divisions in the zebrafish neural tube.

    Science.gov (United States)

    Alexandre, Paula; Reugels, Alexander M; Barker, David; Blanc, Eric; Clarke, Jonathan D W

    2010-06-01

    In the developing CNS, asymmetric cell division is critical for maintaining the balanced production of differentiating neurons while renewing the population of neural progenitors. In invertebrates, this process depends on asymmetric inheritance of fate determinants during progenitor divisions. A similar mechanism is widely believed to underlie asymmetrically fated divisions in vertebrates, but compelling evidence for this is missing. We used live imaging of individual progenitors in the intact zebrafish embryo CNS to test this hypothesis. We found that asymmetric inheritance of a subcellular domain is strongly correlated with asymmetric daughter fates and our results reveal an unexpected feature of this process. The daughter cell destined to become a neuron was derived from the more apical of the two daughters, whereas the more basal daughter inherited the basal process and replenished the apical progenitor pool.

  11. 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...

  12. 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...

  13. 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.

  14. Rectification of motion in nonlinear media with asymmetric random drive

    International Nuclear Information System (INIS)

    We consider moving particles in media with nonlinear friction and drive them by an asymmetric dichotomic Markov process. Due to different energy dissipations, during the forward and backward stroke, we obtain a mean non-vanishing directed flow of the particles. Starting with the stationary velocity distribution, we calculate the stationary current of particles, the variance and the relative variance in dependence on the degree of nonlinearity of the friction, on the asymmetry and for different strengths of friction. In two dimensions the particle performs diffusional motion, if in addition the direction of the asymmetric drive changes stochastically.

  15. Smurfs have "fused" into the asymmetric division of stem cells

    Institute of Scientific and Technical Information of China (English)

    Steven Y. Cheng; Ying E. Zhang

    2011-01-01

    @@ The asymmetric cell division is the way in which a stem cell divides into one daughter stem cell and one differentiated daughter cell.This process is one of the key principles of developmental biology that ensures the perpetual supply of stem cells while allowing a particular cell lineage to be populated.During Drosophila oogenesis, the fate of the daughter stem cell produced from the asymmetric division of germline stem cells (GSCs) is specified by Decapentaplegic (Dpp), but the other daughter cell has almost equal access to the Dpp signal.

  16. 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.

  17. 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.

  18. Originally Asymmetric Dark Matter

    CERN Document Server

    Okada, Nobuchika

    2012-01-01

    We propose a scenario with a fermion dark matter, where the dark matter particle used to be the Dirac fermion, but it takes the form of the Majorana fermion at a late time. The relic number density of the dark matter is determined by the dark matter asymmetry generated through the same mechanism as leptogenesis when the dark matter was the Dirac fermion. After efficient dark matter annihilation processes have frozen out, a phase transition of a scalar field takes place and generates Majorana mass terms to turn the dark matter particle into the Majorana fermion. In order to address this scenario in detail, we propose two simple models. The first one is based on the Standard Model (SM) gauge group and the dark matter originates the $SU(2)_L$ doublet Dirac fermion, analogous to the Higgsino-like neutralino in supersymmetric models. We estimate the spin-independent/dependent elastic scattering cross sections of this late-time Majorana dark matter with a proton and find the possibility to discover it by the direct...

  19. Time Asymmetric Quantum Mechanics

    Directory of Open Access Journals (Sweden)

    Arno R. Bohm

    2011-09-01

    Full Text Available The meaning of time asymmetry in quantum physics is discussed. On the basis of a mathematical theorem, the Stone-von Neumann theorem, the solutions of the dynamical equations, the Schrödinger equation (1 for states or the Heisenberg equation (6a for observables are given by a unitary group. Dirac kets require the concept of a RHS (rigged Hilbert space of Schwartz functions; for this kind of RHS a mathematical theorem also leads to time symmetric group evolution. Scattering theory suggests to distinguish mathematically between states (defined by a preparation apparatus and observables (defined by a registration apparatus (detector. If one requires that scattering resonances of width Γ and exponentially decaying states of lifetime τ=h/Γ should be the same physical entities (for which there is sufficient evidence one is led to a pair of RHS's of Hardy functions and connected with it, to a semigroup time evolution t_0≤t<∞, with the puzzling result that there is a quantum mechanical beginning of time, just like the big bang time for the universe, when it was a quantum system. The decay of quasi-stable particles is used to illustrate this quantum mechanical time asymmetry. From the analysis of these processes, we show that the properties of rigged Hilbert spaces of Hardy functions are suitable for a formulation of time asymmetry in quantum mechanics.

  20. Asymmetric condensed dark matter

    Science.gov (United States)

    Aguirre, Anthony; Diez-Tejedor, Alberto

    2016-04-01

    We explore the viability of a boson dark matter candidate with an asymmetry between the number densities of particles and antiparticles. A simple thermal field theory analysis confirms that, under certain general conditions, this component would develop a Bose-Einstein condensate in the early universe that, for appropriate model parameters, could survive the ensuing cosmological evolution until now. The condensation of a dark matter component in equilibrium with the thermal plasma is a relativistic process, hence the amount of matter dictated by the charge asymmetry is complemented by a hot relic density frozen out at the time of decoupling. Contrary to the case of ordinary WIMPs, dark matter particles in a condensate must be lighter than a few tens of eV so that the density from thermal relics is not too large. Big-Bang nucleosynthesis constrains the temperature of decoupling to the scale of the QCD phase transition or above. This requires large dark matter-to-photon ratios and very weak interactions with standard model particles.

  1. 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

  2. Quality Characteristics Distribution and Its Simulation Based on Asymmetric Tolerances

    Institute of Scientific and Technical Information of China (English)

    ZHU Wei; LI Yuan-sheng

    2003-01-01

    The application of normal distribution for quality characteristics has its limits on the condition that specification interval is asymmetric. In this paper, the compound normal distribution N(L,σ21,σ22) was proposed and simulated, the property of the parameters L、σ1 and σ2 was studied. The distribution was further applied toangle quality process control.

  3. 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.

  4. 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...

  5. 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...

  6. 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.

  7. Domain-wall theory and nonstationarity in driven flow with exclusion

    Science.gov (United States)

    Stinchcombe, R. B.; de Queiroz, S. L. A.

    2016-07-01

    We study the dynamical evolution toward steady state of the stochastic nonequilibrium model known as the totally asymmetric simple exclusion process, in both uniform and nonuniform (staggered) one-dimensional systems with open boundaries. Domain-wall theory and numerical simulations are used and, where pertinent, their results are compared to existing mean-field predictions and exact solutions where available. For uniform chains we find that the inclusion of fluctuations inherent to the domain-wall formulation plays a crucial role in providing good agreement with simulations, which is severely lacking in the corresponding mean-field predictions. For alternating-bond chains the domain-wall predictions for the features of the phase diagram in the parameter space of injection and ejection rates turn out to be realized only in an incipient and quantitatively approximate way. Nevertheless, significant quantitative agreement can be found between several additional domain-wall theory predictions and numerics.

  8. Uncovering the link between malfunctions in Drosophila neuroblast asymmetric cell division and tumorigenesis

    Directory of Open Access Journals (Sweden)

    Kelsom Corey

    2012-11-01

    Full Text Available Abstract Asymmetric cell division is a developmental process utilized by several organisms. On the most basic level, an asymmetric division produces two daughter cells, each possessing a different identity or fate. Drosophila melanogaster progenitor cells, referred to as neuroblasts, undergo asymmetric division to produce a daughter neuroblast and another cell known as a ganglion mother cell (GMC. There are several features of asymmetric division in Drosophila that make it a very complex process, and these aspects will be discussed at length. The cell fate determinants that play a role in specifying daughter cell fate, as well as the mechanisms behind setting up cortical polarity within neuroblasts, have proved to be essential to ensuring that neurogenesis occurs properly. The role that mitotic spindle orientation plays in coordinating asymmetric division, as well as how cell cycle regulators influence asymmetric division machinery, will also be addressed. Most significantly, malfunctions during asymmetric cell division have shown to be causally linked with neoplastic growth and tumor formation. Therefore, it is imperative that the developmental repercussions as a result of asymmetric cell division gone awry be understood.

  9. Exclusive Dealing and Entry

    OpenAIRE

    João Leão

    2008-01-01

    This paper examines the use of exclusive dealing agreements to prevent the entry of rival firms. An exclusive dealing agreement is a contract between a buyer and a seller where the buyer commits to buy a good exclusively from the seller. One main concern of the literature is to explain how an incumbent seller is able to persuade the buyers to sign an exclusive dealing agreement that deters the entry of a more efficient rival seller. We propose a new explanation when the buyers are downstream ...

  10. 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...

  11. 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.

  12. 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

  13. 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...

  14. 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.

  15. 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...

  16. C. elegans HAM-1 functions in the nucleus to regulate asymmetric neuroblast division.

    Science.gov (United States)

    Leung, Amy; Hua, Khang; Ramachandran, Pavitra; Hingwing, Kyla; Wu, Maria; Koh, Pei Luan; Hawkins, Nancy

    2016-02-01

    All 302 neurons in the C. elegans hermaphrodite arise through asymmetric division of neuroblasts. During embryogenesis, the C. elegans ham-1 gene is required for several asymmetric neuroblast divisions in lineages that generate both neural and apoptotic cells. By antibody staining, endogenous HAM-1 is found exclusively at the cell cortex in many cells during embryogenesis and is asymmetrically localized in dividing cells. Here we show that in transgenic embryos expressing a functional GFP::HAM-1 fusion protein, GFP expression is also detected in the nucleus, in addition to the cell cortex. Consistent with the nuclear localization is the presence of a putative DNA binding winged-helix domain within the N-terminus of HAM-1. Through a deletion analysis we determined that the C-terminus of the protein is required for nuclear localization and we identified two nuclear localization sequences (NLSs). A subcellular fractionation experiment from wild type embryos, followed by Western blotting, revealed that endogenous HAM-1 is primarily found in the nucleus. Our analysis also showed that the N-terminus is necessary for cortical localization. While ham-1 function is essential for asymmetric division in the lineage that generates the PLM mechanosensory neuron, we showed that cortical localization may not required. Thus, our results suggest that there is a nuclear function for HAM-1 in regulating asymmetric neuroblast division and that the requirement for cortical localization may be lineage dependent.

  17. Selective and simultaneous determination of phosphate and silicate ions in leaching process waters for ceramics glaze raw materials of narutal origin by ion-exclusion chromatography coupled with UV-detection after postcolumn derivatization.

    Science.gov (United States)

    Ikedo, Mikaru; Mori, Masanobu; Kurachi, Kazumasa; Hu, Wenzhi; Tanaka, Kazuhiko

    2006-01-01

    The selective and simultaneous ion-exclusion chromatography (IEC) with UV-detection on a weakly acidic cation-exchange resin column in the H+ -form (TSKgel Super IC-A/C) was developed and applied for the simultaneous determination of phosphate and silicate ions as the water quality parameters required for optimizing the water-leaching process for ceramics glaze raw materials of natural origin including feldspar, woods-ash, and straw-ash. Phosphate and silicate ions in these water-leaching process water samples were separated selectively from the coexisting anions such as sulfate, chloride, nitrate and carbonate ions, based on the ion-exclusion separation mechanism. They were detected selectively and simultaneously by a postcolumn derivatization with molybdenum-yellow using the UV-detector. Under the optimized separation and detection conditions (eluent, 0-1 mM sulfuric acid; reactant, 10 mM sodium molybdate-25 mM sulfuric acid; detector, UV at 370 nm; temperature, 45 degrees C), the linearity of calibration was in the range 0.1 - 10 ppm for both phosphate and silicate ions, and the detection limits at S/N = 3 were 2.58 ppb for silicate ions and 4.75 ppb for phosphate ions. The effectiveness of this method was demonstrated in practical applications to the water-leaching process for some ceramics glaze raw materials. PMID:16429785

  18. Asymmetric AgPd-AuNR heterostructure with enhanced photothermal performance and SERS activity

    Science.gov (United States)

    Zhang, Han; Liu, Zeke; Kang, Xiaolin; Guo, Jun; Ma, Wanli; Cheng, Si

    2016-01-01

    Most as-reported nanostructures through galvanic replacement reactions are still symmetric hollow structures, until now. Asymmetric structures fabricated through a galvanic replacement reaction have been rarely reported. However, asymmetric heterostructures can generally lead to new intriguing properties through asymmetric synergistic coupling. Here, we report a simple synthesis of an asymmetric one-ended AgPd bimetal on Au nanorods (AuNR) by combining a galvanic replacement reaction with an Ostwald ripening process. The morphological evolution from a nanodumbbell to a dandelion structure is thoroughly investigated. The unique asymmetric AgPd-AuNR heterostructures possess the required plasmonic performance and avoid strong damping caused by the poor plasmonic metal Pd, resulting in a superior photothermal heating performance and enhanced SERS sensitivity for in situ monitoring of a catalytic reaction compared with the symmetric counterparts.Most as-reported nanostructures through galvanic replacement reactions are still symmetric hollow structures, until now. Asymmetric structures fabricated through a galvanic replacement reaction have been rarely reported. However, asymmetric heterostructures can generally lead to new intriguing properties through asymmetric synergistic coupling. Here, we report a simple synthesis of an asymmetric one-ended AgPd bimetal on Au nanorods (AuNR) by combining a galvanic replacement reaction with an Ostwald ripening process. The morphological evolution from a nanodumbbell to a dandelion structure is thoroughly investigated. The unique asymmetric AgPd-AuNR heterostructures possess the required plasmonic performance and avoid strong damping caused by the poor plasmonic metal Pd, resulting in a superior photothermal heating performance and enhanced SERS sensitivity for in situ monitoring of a catalytic reaction compared with the symmetric counterparts. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr07333b

  19. 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.

  20. 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.

  1. Positioning of polarity formation by extracellular signaling during asymmetric cell division.

    Science.gov (United States)

    Seirin Lee, Sungrim

    2016-07-01

    Anterior-posterior (AP) polarity formation of cell membrane proteins plays a crucial role in determining cell asymmetry, which ultimately generates cell diversity. In Caenorhabditis elegans, a single fertilized egg cell (P0), its daughter cell (P1), and the germline precursors (P2 and P3 cells) form two exclusive domains of different PAR proteins on the membrane along the anterior-posterior axis. However, the phenomenon of polarity reversal has been observed in which the axis of asymmetric cell division of the P2 and P3 cells is formed in an opposite manner to that of the P0 and P1 cells. The extracellular signal MES-1/SRC-1 has been shown to induce polarity reversal, but the detailed mechanism remains elusive. Here, using a mathematical model, I explore the mechanism by which MES-1/SRC-1 signaling can induce polarity reversal and ultimately affect the process of polarity formation. I show that a positive correlation between SRC-1 and the on-rate of PAR-2 is the essential mechanism underlying polarity reversal, providing a mathematical basis for the orientation of cell polarity patterns. PMID:27086039

  2. Enhanced Information Exclusion Relations

    OpenAIRE

    Xiao, Yunlong; Jing, Naihuan; Li-Jost, Xianqing

    2016-01-01

    In Hall's reformulation of the uncertainty principle, the entropic uncertainty relation occupies a core position and provides the first nontrivial bound for the information exclusion principle. Based upon recent developments on the uncertainty relation, we present new bounds for the information exclusion relation using majorization theory and combinatoric techniques, which reveal further characteristic properties of the overlap matrix between the measurements.

  3. Explaining Social Exclusion

    NARCIS (Netherlands)

    Gerda Jehoel-Gijsbers; Cok Vrooman

    2007-01-01

    Although social exclusion has become a key issue on the European policy agenda in recent years, both the social phenomena the term refers to and the best way to monitor these remain unclear. In response to this, we developed a conceptual model for social exclusion and a methodology for its empirical

  4. 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...

  5. 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

  6. Asymmetric sequential Landau-Zener dynamics of Bose condensed atoms in a cavity

    CERN Document Server

    Huang, Jiahao; Qin, Xizhou; Zhong, Honghua; Lee, Chaohong

    2016-01-01

    We explore the asymmetric sequential Landau-Zener (LZ) dynamics in an ensemble of interacting Bose condensed two-level atoms coupled with a cavity field. Assuming the couplings between all atoms and the cavity field are identical, the interplay between atom-atom interaction and detuning may lead to a series of LZ transitions. Unlike the conventional sequential LZ transitions, which are symmetric to the zero detuning, the LZ transitions of Bose condensed atoms in a cavity field are asymmetric and sensitively depend on the photon number distribution of the cavity. In LZ processes involving single excitation numbers, both the variance of the relative atom number and the step slope of the sequential population ladder are asymmetric, and the asymmetry become more significant for smaller excitation numbers. Furthermore, in LZ processes involving multiple excitation numbers, there may appear asymmetric population ladders with decreasing step heights. During a dynamical LZ process, due to the atom-cavity coupling, th...

  7. 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...

  8. 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.

  9. Tunable asymmetric mode conversion using the dark-mode of three-mode waveguide system.

    Science.gov (United States)

    Kim, Joonsoo; Lee, Seung-Yeol; Lee, Yohan; Kim, Hwi; Lee, Byoungho

    2014-11-17

    A design scheme for low-reflection asymmetric mode conversion structure in three-mode waveguide system is proposed. By using a dark-mode of three-mode system, which can be interpreted in terms of destructive interference of transition amplitudes, the transmission characteristics for forward and backward directions can be designed separately. After explanation of the proposed design scheme, we demonstrate an example of asymmetric mode converter that consists of two gratings. The proposed scheme may be useful for the design of tunable asymmetric transmission devices due to its design flexibility and efficient design process. PMID:25402109

  10. A THRESHOLD COINTEGRATION ANALYSIS OF ASYMMETRIC ADJUSTMENTS IN THE GHANAIAN MAIZE MARKETS

    Directory of Open Access Journals (Sweden)

    H. de-Graft Acquah

    2012-08-01

    Full Text Available This paper analyzes the long-run equilibrium relationship between retail and wholesale Ghanaian maize prices with cointegration test assuming asymmetric adjustment. Using the Enders-Siklos asymmetric cointegration tests, it is found that the retail and wholesale prices are cointegrated with threshold adjustment. Furthermore, the adjustment process is asymmetric when the retail and wholesale prices adjust to achieve the long-term equilibrium. Finally, there is faster convergence for negative deviations from long-term equilibrium than for positive deviations. These results imply that price increases tend to persist whereas decreases tend to revert quickly towards equilibrium.

  11. 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

  12. Asymmetrical Information and Public Failure in the Myriad Decision

    Directory of Open Access Journals (Sweden)

    Reginald Shareef

    2014-09-01

    Full Text Available The Public Value concept is a Public Management normative process that utilizes efficiency and ethics as co-equal determinants to assess organizational outcomes. As such, Public Value represents what Ghoshal calls intellectual pluralism or the utilization of normative management processes in the social sciences to challenge the intellectual absolutism of the Chicago School. One discipline where Public Value can be used to assess normative results is Legal Studies’ antitrust field. This research applies Public Value criteria in evaluating the U.S. Supreme Court’s 2013 ruling in Association for Molecular Pathology v. Myriad Genetics. The conclusions tentatively found the Court’s decision will (a create Public Value at the macro level but (b trigger public failure at the micro level for poor women because of an asymmetrical information network. This outcome fits with Stiglitz’s hypothesis concerning asymmetrical information and market failure. Further empirical research on Myriad’s policy is recommended.

  13. Model of reversible vesicular transport with exclusion

    Science.gov (United States)

    Bressloff, Paul C.; Karamched, Bhargav R.

    2016-08-01

    A major question in neurobiology concerns the mechanics behind the motor-driven transport and delivery of vesicles to synaptic targets along the axon of a neuron. Experimental evidence suggests that the distribution of vesicles along the axon is relatively uniform and that vesicular delivery to synapses is reversible. A recent modeling study has made explicit the crucial role that reversibility in vesicular delivery to synapses plays in achieving uniformity in vesicle distribution, so called synaptic democracy (Bressloff et al 2015 Phys. Rev. Lett. 114 168101). In this paper we generalize the previous model by accounting for exclusion effects (hard-core repulsion) that may occur between molecular motor-cargo complexes (particles) moving along the same microtubule track. The resulting model takes the form of an exclusion process with four internal states, which distinguish between motile and stationary particles, and whether or not a particle is carrying vesicles. By applying a mean field approximation and an adiabatic approximation we reduce the system of ODEs describing the evolution of occupation numbers of the sites on a 1D lattice to a system of hydrodynamic equations in the continuum limit. We find that reversibility in vesicular delivery allows for synaptic democracy even in the presence of exclusion effects, although exclusion does exacerbate nonuniform distributions of vesicles in an axon when compared with a model without exclusion. We also uncover the relationship between our model and other models of exclusion processes with internal states.

  14. Asymmetric coherent transmission for single particle diode and gyroscope

    OpenAIRE

    Yang, S.; Song, Z; 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 g...

  15. DIFLUORPHOS and SYNPHOS in asymmetric catalysis: Synthetic applications

    Indian Academy of Sciences (India)

    Sebastien Prevost; Tahar Ayad; Jean-Pierre Genet; Phannarath Phansavath; Virginie Ratovelomanana-Vidal

    2014-03-01

    Enantiomerically pure diphosphines play an important role in various homogeneous metalcatalyzed asymmetric reactions. Over the last few years, our group has been involved in the design and synthesis of atropisomeric ligands named SYNPHOS and DIFLUORPHOS with complementary stereoelectronic properties. This paper shows the high catalytic performances of DIFLUORPHOS, SYNPHOS and SYNPHOS analogues for some C-H and C-C bond forming processes as well as for the synthesis of biorelevant targets.

  16. 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...

  17. Bargaining with asymmetric information in non-stationary markets

    OpenAIRE

    Daniel Trefler

    1999-01-01

    The Rubinstein and Wolinsky bargaining-in-markets framework is modified by the introduction of asymmetric information and non-stationarity. Non-stationarity is introduced in the form of an arbitrary stochastic Markov process which captures the dynamics of market entry and pairwise matching. A new technique is used for establishing existence and characterizing the unique outcome of a non-stationary market equilibrium. The impact of market supply and demand on bilateral bargaining outcomes and ...

  18. Watermarking in gyrator domain using an asymmetric cryptosystem

    Science.gov (United States)

    Vashisth, Sunanda; Yadav, A. K.; Singh, Hukun; Singh, Kehar

    2015-06-01

    A watermarking scheme is proposed based on optical asymmetric cryptography using double random phase encoding in the gyrator transform domain. It is based on the phase and amplitude truncation during the encryption process. The scheme is validated through computer simulations showing the scheme's sensitivity to decryption keys and orders of the gyrator transform. The occlusion and noise attacks have also been analysed. The proposed scheme is significantly resistant to both these attacks.

  19. 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

  20. Exclusion, employment and opportunity

    OpenAIRE

    Atkinson, Tony; Hills, John

    1998-01-01

    The relationships between employment, education, opportunity, social exclusion and poverty are central to current policy debates. Atkinson argues that the concepts of poverty, unemployment and social exclusion are closely related, but are not the same. People may be poor without being socially excluded, and vice versa. Unemployment may cause poverty, but this can be prevented. Equally, marginal jobs do not ensure social inclusion. Britton argues that convential economic analysis misses a key ...

  1. Enhanced Information Exclusion Relations

    Science.gov (United States)

    Xiao, Yunlong; Jing, Naihuan; Li-Jost, Xianqing

    2016-01-01

    In Hall’s reformulation of the uncertainty principle, the entropic uncertainty relation occupies a core position and provides the first nontrivial bound for the information exclusion principle. Based upon recent developments on the uncertainty relation, we present new bounds for the information exclusion relation using majorization theory and combinatoric techniques, which reveal further characteristic properties of the overlap matrix between the measurements. PMID:27460975

  2. Exclusive scattering off the deuteron

    Energy Technology Data Exchange (ETDEWEB)

    Amrath, D.

    2007-12-15

    Exclusive processes are a special class of processes giving insight into the inner structure of hadrons. In this thesis we consider two exclusive processes and compute their total cross sections as well as the beam charge and beam polarization asymmetries for different kinematical constraints. These calculations o er the opportunity to get access to the nonperturbative GPDs. Theoretically they can be described with the help of models. The rst process we investigate contains a GPD of the pion, which is basically unknown so far. We include different models and make predictions for observables that could in principle be measured at HERMES at DESY and CLAS at JLab. The second process we consider is electron-deuteron scattering in the kinematical range where the deuteron breaks up into a proton and a neutron. This can be used to investigate the neutron, which cannot be taken as a target due to its lifetime of approximately 15 minutes. For the calculation of the electron-deuteron cross section we implement models for the proton and neutron GPDs. Once there are experimental data available our calculations are ready for comparison. (orig.)

  3. 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.

  4. 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.

  5. 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.

  6. 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 ...

  7. 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.

  8. 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.

  9. 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...

  10. 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

  11. 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.

  12. Influence of Asymmetric Structure on the Process of Fracture Splitting Oblique Incision Connecting Rod%结构不对称对斜切口连杆裂解影响分析

    Institute of Scientific and Technical Information of China (English)

    赵勇; 杨慎华; 寇淑清; 金文明

    2012-01-01

    Asymmetric structure affects on cracking order and quality when oblique incision connecting rod is split by way of fracture.The finite element models of oblique incision connecting rod with different cracking groove depth were set up.Using this model and the fracture toughness of oblique incision connecting rod material which was measured by test as the onset criterion,the onset of cracking of oblique incision connecting rod fracture splitting was numerically simulated in the quasi-static loading case by FEM software.Simulation results show that the optimization of the depth parameters on both sides of cracking groove of oblique incision connecting rod can reduce the time lag of onset of cracking groove on both sides which is caused by the asymmetric structure in the course of fracture splitting of the oblique incision connecting rod.Experiments of fracture splitting of the oblique incision connecting rod were carried out and the time lag of onset of cracking groove on both sides was measured by electromotive strain method.Good agreement is found between experimental and numerical results.%分析了斜切口连杆结构不对称对裂解加工中两侧裂解槽起裂时序及裂解质量的影响.建立了斜切口裂解连杆有限元模型,以试验确定的斜切口连杆材料断裂韧性参数为起裂判据,变化斜切口裂解连杆有限元模型的两侧裂解槽深差,进行了斜切口连杆裂解起裂准静态有限元分析.模拟结果表明,通过优化斜切口连杆两侧裂解槽深度参数可以减小由于结构不对称引起的斜切口连杆裂解加工中两侧裂解槽的起裂时间差.进行了不同槽深情况的斜切口连杆裂解试验研究,通过电测方法测定了试验中斜切口连杆两侧裂解起裂时间差,试验结果与数值模拟结果相比有较好的一致性.

  13. 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.

  14. 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.

  15. R & D STRATEGIC INVESTMENT IN AN ASYMMETRICAL CASE

    Institute of Scientific and Technical Information of China (English)

    Minggao XUE; Pu GONG

    2006-01-01

    This article analyzes R & D investment decisions in an asymmetrical case. The investment decisions share three important characteristics. First, the investment is completely irreversible. Second,there are two kinds of uncertainties over the future returns from the investment and over technology in R & D process, respectively. Third, there is strategic competition in the asymmetrical case. This article presents the optimal investment threshold values and the optimal investment rule of high-efficient firm (leader), and shows that the investment threshold values are reduced by competition of two firms.Finally, the mixed investment strategies for two firms, the probability that each firm separately exercises the option to invest, and the probability that two firms simultaneously exercise the option are given in the paper.

  16. 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

  17. Proper symmetric and asymmetric endoplasmic reticulum partitioning requires astral microtubules.

    Science.gov (United States)

    Smyth, Jeremy T; Schoborg, Todd A; Bergman, Zane J; Riggs, Blake; Rusan, Nasser M

    2015-08-01

    Mechanisms that regulate partitioning of the endoplasmic reticulum (ER) during cell division are largely unknown. Previous studies have mostly addressed ER partitioning in cultured cells, which may not recapitulate physiological processes that are critical in developing, intact tissues. We have addressed this by analysing ER partitioning in asymmetrically dividing stem cells, in which precise segregation of cellular components is essential for proper development and tissue architecture. We show that in Drosophila neural stem cells, called neuroblasts, the ER asymmetrically partitioned to centrosomes early in mitosis. This correlated closely with the asymmetric nucleation of astral microtubules (MTs) by centrosomes, suggesting that astral MT association may be required for ER partitioning by centrosomes. Consistent with this, the ER also associated with astral MTs in meiotic Drosophila spermatocytes and during syncytial embryonic divisions. Disruption of centrosomes in each of these cell types led to improper ER partitioning, demonstrating the critical role for centrosomes and associated astral MTs in this process. Importantly, we show that the ER also associated with astral MTs in cultured human cells, suggesting that this centrosome/astral MT-based partitioning mechanism is conserved across animal species. PMID:26289801

  18. 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.

  19. 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.

  20. 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.

  1. 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....

  2. 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...

  3. 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...

  4. 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...

  5. 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...

  6. 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 ...

  7. 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

  8. Barbed congruence of the asymmetric chi calculus

    Institute of Scientific and Technical Information of China (English)

    DONG Xiao-ju; FU Yu-xi

    2006-01-01

    The chi calculus is a model of mobile processes. It has evolved from the pi-calculus with motivations from simplification and communication-as-cut-elimination. This paper studies the chi calculus in the framework incorporating asymmetric communication. The major feature of the calculus is the identification of two actions:x/x and τ. The investigation on the barbed bisimilarity shows how the property affects the observational theory.Based on the definition of the barbed bisimilarity, the simulation properties of the barbed bisimilarity are studied. It shows that the algebraic properties of the barbed bisimilarity have changed greatly compared with the chi calculus. Although the definition of the barbed bisimilarity is very simple, the property of closeness under contexts makes it difficult to understand the barbed bisimilarity directly. Therefore an open style definition of the barbed bisimilarity is given, which is a context free description of barbed bisimilarity. Its definition is complex,but it is a well-behaved relation for it coincides with the barbed bisimilarity. It also helps to build an axiomatization system for the barbed congruence. Besides the axioms for the strong barbed bisimilarity, the paper proposes a new tau law and four new update laws for the barbed congruence. Both the operational and algebraic properties of the enriched calculus improve the understanding of the bisimulation behaviors of the model.

  9. Liberal-conservative differences in inclusion-exclusion strategy choice,

    Directory of Open Access Journals (Sweden)

    John D. Jasper

    2008-06-01

    Full Text Available Inclusion and exclusion strategies for allocation of scarce goods involve different processes. The conditions under which one strategy is chosen in favor of the other, however, have not been fully explicated. In the present study, decision makers chose a single strategy after reading through descriptions of 16 potential organ recipients; they then narrowed the list of transplant candidates. Most liberals chose to use exclusion under conditions of abundance and inclusion under scarcity. In contrast, conservatives preferred an inclusion strategy under abundance and exclusion (though not significantly under scarcity. Theoretical implications as well as ongoing work in inclusion-exclusion strategy choice, political ideology, and distributive justice are discussed.

  10. RELATIONSHIP OF TRANSVERSAL ASYMMETRIC FACE AND UNILATERAL POSTERIOR CROSSBITE

    Directory of Open Access Journals (Sweden)

    Indah Dwinursanty

    2006-04-01

    Full Text Available 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 undergone orthodontic treatment or facial surgery were selected. The sample consisted of 15 females and 6 males (15 – 32 years old. Anteroposterior cephalogram was used for determining the difference between right and left of antegonial and the deviation of menton. Criteria for asymmetry were more than 3 mm on Antegonial and 2 mm or more on Menton. Mid Sagital Reference (MSR was used as reference line. Unilateral posterior crossbite could be seen in the dental model. The data was analyzed using Mann Whitney test. It was revealed that from 21 samples, 38.1% was found to have unilateral posterior crossbite involving four posterior teeth. Conclusion: There is no relationship between transveral skeletal symmetry and unilateral posterior crossbite.

  11. Stochastic modeling of cell growth with symmetric or asymmetric division

    Science.gov (United States)

    Marantan, Andrew; Amir, Ariel

    2016-07-01

    We consider a class of biologically motivated stochastic processes in which a unicellular organism divides its resources (volume or damaged proteins, in particular) symmetrically or asymmetrically between its progeny. Assuming the final amount of the resource is controlled by a growth policy and subject to additive and multiplicative noise, we derive the recursive integral equation describing the evolution of the resource distribution over subsequent generations and use it to study the properties of stable resource distributions. We find conditions under which a unique stable resource distribution exists and calculate its moments for the class of affine linear growth policies. Moreover, we apply an asymptotic analysis to elucidate the conditions under which the stable distribution (when it exists) has a power-law tail. Finally, we use the results of this asymptotic analysis along with the moment equations to draw a stability phase diagram for the system that reveals the counterintuitive result that asymmetry serves to increase stability while at the same time widening the stable distribution. We also briefly discuss how cells can divide damaged proteins asymmetrically between their progeny as a form of damage control. In the appendixes, motivated by the asymmetric division of cell volume in Saccharomyces cerevisiae, we extend our results to the case wherein mother and daughter cells follow different growth policies.

  12. Stochastic modeling of cell growth with symmetric or asymmetric division.

    Science.gov (United States)

    Marantan, Andrew; Amir, Ariel

    2016-07-01

    We consider a class of biologically motivated stochastic processes in which a unicellular organism divides its resources (volume or damaged proteins, in particular) symmetrically or asymmetrically between its progeny. Assuming the final amount of the resource is controlled by a growth policy and subject to additive and multiplicative noise, we derive the recursive integral equation describing the evolution of the resource distribution over subsequent generations and use it to study the properties of stable resource distributions. We find conditions under which a unique stable resource distribution exists and calculate its moments for the class of affine linear growth policies. Moreover, we apply an asymptotic analysis to elucidate the conditions under which the stable distribution (when it exists) has a power-law tail. Finally, we use the results of this asymptotic analysis along with the moment equations to draw a stability phase diagram for the system that reveals the counterintuitive result that asymmetry serves to increase stability while at the same time widening the stable distribution. We also briefly discuss how cells can divide damaged proteins asymmetrically between their progeny as a form of damage control. In the appendixes, motivated by the asymmetric division of cell volume in Saccharomyces cerevisiae, we extend our results to the case wherein mother and daughter cells follow different growth policies. PMID:27575162

  13. 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

  14. Contrasting Stories of Inclusion/Exclusion in the Chemistry Classroom

    Science.gov (United States)

    Gomes, Maria de Fatima Cardoso; Mortimer, Eduardo F.; Kelly, Gregory J.

    2011-01-01

    This article reports on the construction process of inclusion/exclusion for high school chemistry students in two schools in Belo Horizonte, the capital of Minas Gerais State, Brazil. We examined the interactional accomplishment of inclusion/exclusion of four students, two from a private school and two from a public school. The aim of this article…

  15. All-optical adder/subtractor based on tera-hertz optical asymmetric demultiplexer

    Institute of Scientific and Technical Information of China (English)

    Dilip Kumar Gayen; Rajat Kumar Pal; Jitendra Nath Roy

    2009-01-01

    An all-optical adder/subtractor (A/S) unit with the help of terahertz optical asymmetric demultiplexer (TOAD) is proposed.Tile all-optical A/S unit with a set of all-optical full-adders and optical exclusive-ORs (XORs),can be used to perform a fast central processor unit using optical hardware components.We try to exploit the advantages of TOAD-based optical switch to design an integrated all-optical circuit which can perform binary addition and subtraction.With computer simulation results confirming the described methods,conclusions are given.

  16. Spacecraft observations and analytic theory of crescent-shaped electron distributions in asymmetric magnetic reconnection

    CERN Document Server

    Egedal, J; Daughton, W; Wetherton, B; Cassak, P A; Chen, L -J; Lavraud, B; Trobert, R B; Dorelli, J; Gershman, D J; Avanov, L A

    2016-01-01

    Supported by a kinetic simulation, we derive an exclusion energy parameter $\\cal{E}_X$ providing a lower kinetic energy bound for an electron to cross from one inflow region to the other during magnetic reconnection. As by a Maxwell Demon, only high energy electrons are permitted to cross the inner reconnection region, setting the electron distribution function observed along the low density side separatrix during asymmetric reconnection. The analytic model accounts for the two distinct flavors of crescent-shaped electron distributions observed by spacecraft in a thin boundary layer along the low density separatrix.

  17. 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.

  18. Social exclusion anxiety

    DEFF Research Database (Denmark)

    Søndergaard, Dorte Marie

    2014-01-01

    . The concepts I work with are the need for belonging, social exclusion anxiety and the production of contempt and dignity by both children and adults. I develop a new definition of bullying, drawing upon Judith Butler’s (1999) concept of ‘abjection’ as well as Karen Barad’s concept of ‘intra-acting forces...

  19. Dimensions of social exclusion

    NARCIS (Netherlands)

    Stella Hoff; Cok Vrooman

    2011-01-01

    Original title: Dimensies van sociale uitsluiting SCP has carried out research since 2004 on the occurrence and causes of social exclusion, both among the Dutch population as a whole and within certain groups (the elderly, children). The questionnaire used for this has been regularly updated on the

  20. Social exclusion of children

    NARCIS (Netherlands)

    Annette Roest; Anne Marike Lokhorst; Cok Vrooman

    2010-01-01

    Original title: Sociale uitsluiting bij kinderen. Combating social exclusion of children is a subject that has received growing attention in Dutch government policy in recent years. To date, however, no analysis has been performed to ascertain the extent and origins of this phenomenon. This report

  1. Ombuds' Corner: Social exclusion

    CERN Multimedia

    CERN bulletin

    2012-01-01

    In this special video edition of the Ombuds' Corner, Ombudsman Vincent Vuillemin takes a look at a social exclusion at CERN. Please note that the characters and situations appearing in this work are fictitious, and any resemblance to real persons or events is purely coincidental.

  2. Ombuds' Corner: Social exclusion

    CERN Multimedia

    Vincent Vuillemin

    2012-01-01

    In this special video edition of the Ombuds' Corner, Vincent Vuillemin takes a look at a social exclusion at CERN. Please note that the characters and situations appearing in this work are fictitious, and any resemblance to real persons or events is purely coincidental.   Contact the Ombuds Early!

  3. The Mechanisms of Interpersonal Privacy in Social Networking Websites: A Study of Subconscious Processes, Social Network Analysis, and Fear of Social Exclusion

    Science.gov (United States)

    Hammer, Bryan

    2013-01-01

    With increasing usage of social networking sites like Facebook there is a need to study privacy. Previous research has placed more emphasis on outcome-oriented contexts, such as e-commerce sites. In process-oriented contexts, like Facebook, privacy has become a source of conflict for users. The majority of architectural privacy (e.g. privacy…

  4. Starvation-free mutual exclusion with semaphores

    NARCIS (Netherlands)

    Hesselink, Wim H.; IJbema, Mark

    2013-01-01

    The standard implementation of mutual exclusion by means of a semaphore allows starvation of processes. Between 1979 and 1986, three algorithms were proposed that preclude starvation. These algorithms use a special kind of semaphore. We model this so-called buffered semaphore rigorously and provide

  5. [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.

  6. Central Exclusive Production at LHCb

    CERN Document Server

    McNulty, Ronan

    2016-01-01

    Central Exclusive Production (CEP) is a unique process at hadron machines in which particles are produced via colourless propagators. LHCb have measured the cross-sections for the CEP of vector mesons, $J/\\psi,\\psi(2S),\\Upsilon(1S),\\Upsilon(2S)$ and $\\Upsilon(3S)$, which are photo-produced. In the double pomeron exchange process, preliminary measurements have been made of $\\chi_{c0},\\chi_{c1}, \\chi_{c2}$ meson production while the first observations of the CEP of pairs of charmonia, $J/\\psi J/\\psi$ and $J/\\psi \\psi(2S)$, have been made and limits obtained on the pair production of other charmonia.

  7. 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....

  8. 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.

  9. 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.

  10. 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

  11. Development of a preliminary design of a method to measure the effectiveness of virus exclusion during water process reclamation at zero-G

    Science.gov (United States)

    Fraser, A. S.; Wells, A. F.; Tenoso, H. J.; Linnecke, C. B.

    1976-01-01

    Organon Diagnostics has developed, under NASA sponsorship, a monitoring system to test the capability of a water recovery system to reject the passage of viruses into the recovered water. In this system, a non-pathogenic marker virus, bacteriophage F2, is fed into the process stream before the recovery unit and the reclaimed water is assayed for its presence. An engineering preliminary design has been performed as a parallel effort to the laboratory development of the marker virus test system. Engineering schematics and drawings present a preliminary instrument design of a fully functional laboratory prototype capable of zero-G operation.

  12. Asymmetric transfer of auditory perceptual learning

    Directory of Open Access Journals (Sweden)

    Sygal eAmitay

    2012-11-01

    Full Text Available Perceptual skills can improve dramatically even with minimal practice. A major and practical benefit of learning, however, is in transferring the improvement on the trained task to untrained tasks or stimuli, yet the mechanisms underlying this process are still poorly understood. Reduction of internal noise has been proposed as a mechanism of perceptual learning, and while we have evidence that frequency discrimination (FD learning is due to a reduction of internal noise, the source of that noise was not determined. In this study, we examined whether reducing the noise associated with neural phase locking to tones can explain the observed improvement in behavioural thresholds. We compared FD training between two tone durations (15 and 100 ms that straddled the temporal integration window of auditory nerve fibers upon which computational modeling of phase locking noise was based. Training on short tones resulted in improved FD on probe tests of both the long and short tones. Training on long tones resulted in improvement only on the long tones. Simulations of FD learning, based on the computational model and on signal detection theory, were compared with the behavioral FD data. We found that improved fidelity of phase locking accurately predicted transfer of learning from short to long tones, but also predicted transfer from long to short tones. The observed lack of transfer from long to short tones suggests the involvement of a second mechanism. Training may have increased the temporal integration window which could not transfer because integration time for the short tone is limited by its duration. Current learning models assume complex relationships between neural populations that represent the trained stimuli. In contrast, we propose that training-induced enhancement of the signal-to-noise ratio offers a parsimonious explanation of learning and transfer that easily accounts for asymmetric transfer of learning.

  13. 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.

  14. 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.

  15. 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.

  16. Implementation of exclusive truck facilities

    Energy Technology Data Exchange (ETDEWEB)

    Fekpe, E. [Battelle Memorial Inst., Columbus, OH (United States). Transportation Market Sector

    2007-07-01

    This paper discussed the issue of highway congestion, safety, and efficiency in freight movement on highways, with particular reference to the challenge of supporting increasing capacity demand from truck traffic. Innovative and practical solutions are needed to address the growing need for more efficient freight movement while maintaining acceptable levels of safety on highways. The concept of exclusive truck facilities (ETFs) is becoming an attractive option as a feasible strategy to help stabilize traffic flow, reduce congestion, improve safety, enhance transportation system management, improve access to freight facilities, and improve efficiency in freight movement along corridors of national importance. ETFs can either be truck only lanes or truckways. Passenger cars may not use ETFs. However, the use of ETFs could involve high costs of construction, maintenance, and acquisition of additional right of way. A cost-benefit analysis was performed for alternative ETF configurations under different traffic and site characteristics. A set of criteria was then proposed for identifying suitable locations for exclusive truck lanes. It was proposed that ETFs are economically feasible at locations with traffic volume of 100,000 vehicles per day or more and with a truck volume of at least 25 per cent of the traffic. In addition, the rate of truck-involved fatal crashes and level of service should be used to prioritize preliminary candidate locations that satisfy the traffic criteria. Consideration should also be given to the existence of freight terminals, ports, processing centers or regional distribution centres that are close to highways. 11 refs., 1 tab.

  17. ASYMMETRIC PRICE TRANSMISSION MODELING: THE IMPORTANCE OF MODEL COMPLEXITY AND THE PERFORMANCE OF THE SELECTION CRITERIA

    Directory of Open Access Journals (Sweden)

    Henry de-Graft Acquah

    2013-01-01

    Full Text Available Information Criteria provides an attractive basis for selecting the best model from a set of competing asymmetric price transmission models or theories. However, little is understood about the sensitivity of the model selection methods to model complexity. This study therefore fits competing asymmetric price transmission models that differ in complexity to simulated data and evaluates the ability of the model selection methods to recover the true model. The results of Monte Carlo experimentation suggest that in general BIC, CAIC and DIC were superior to AIC when the true data generating process was the standard error correction model, whereas AIC was more successful when the true model was the complex error correction model. It is also shown that the model selection methods performed better in large samples for a complex asymmetric data generating process than with a standard asymmetric data generating process. Except for complex models, AIC's performance did not make substantial gains in recovery rates as sample size increased. The research findings demonstrate the influence of model complexity in asymmetric price transmission model comparison and selection.

  18. 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.

  19. Asymmetric Synthesis Using Enzymes in Supercritical CO2

    Institute of Scientific and Technical Information of China (English)

    T. Matsuda

    2005-01-01

    @@ 1Introduction Great efforts have been extended to catalysis in supercritical CO2 (scCO2) since the early 1990's due to the environmental friendliness, high diffusivity, high solubilizing power, easiness of the product separation,etc.. A combined process of scCO2 and enzymatic catalyst system would be a promising synthetic tool to produce optically active compounds because the enzyme has advantages of being natural and having high enantioselectivity in nature. Here we report asymmetric synthesis using lipase and alcohol dehydrogenase in scCO2[1,2].

  20. Passage times of asymmetric anomalous walks with multiple paths

    Energy Technology Data Exchange (ETDEWEB)

    Caceres, Manuel O [Centro Atomico Bariloche, Instituto Balseiro, and CONICET, 8400, Bariloche (Argentina); Insua, G Liliana [Facultad de Ingenieria, Univ. Nac. del Comahue, 8300, Neuquen (Argentina)

    2005-04-29

    We investigate the transient and the long-time behaviour of asymmetric anomalous walks in heterogeneous media. Two types of disorder are worked out explicitly: weak and strong disorder; in addition, the occurrence of disordered multiple paths is considered. We calculate the first passage time distribution of the associated stochastic transport process. We discuss the occurrence of the crossover from a power law to an exponential decay for the long-time behaviour of the distribution of the first passage times of disordered biased walks.

  1. 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.

  2. 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.

  3. Social exclusion in finite populations

    Science.gov (United States)

    Li, Kun; Cong, Rui; Wu, Te; Wang, Long

    2015-04-01

    Social exclusion, keeping free riders from benefit sharing, plays an important role in sustaining cooperation in our world. Here we propose two different exclusion regimes, namely, peer exclusion and pool exclusion, to investigate the evolution of social exclusion in finite populations. In the peer exclusion regime, each excluder expels all the defectors independently, and thus bears the total cost on his own, while in the pool exclusion regime, excluders spontaneously form an institution to carry out rejection of the free riders, and each excluder shares the cost equally. In a public goods game containing only excluders and defectors, it is found that peer excluders outperform pool excluders if the exclusion costs are small, and the situation is converse once the exclusion costs exceed some critical points, which holds true for all the selection intensities and different update rules. Moreover, excluders can dominate the whole population under a suitable parameters range in the presence of second-order free riders (cooperators), showing that exclusion has prominent advantages over common costly punishment. More importantly, our finding indicates that the group exclusion mechanism helps the cooperative union to survive under unfavorable conditions. Our results may give some insights into better understanding the prevalence of such a strategy in the real world and its significance in sustaining cooperation.

  4. The Inclusiveness of Exclusion

    OpenAIRE

    Paulo Barelli; Suren Basov; Mauricio Bugarin; Ian King

    2010-01-01

    We extend Armstrong’s (1996) result on exclusion in multi-dimensional screening models in two key ways, providing support for the view that this result is quite generic and applicable to many different markets. First, we relax the strong technical assumptions he imposed on preferences and consumer types. Second, we extend the result beyond the monopolistic market structure to generalized oligopoly settings with entry. We also analyse applications to several quite different settings: credit ma...

  5. NEET and Youth Exclusion

    Directory of Open Access Journals (Sweden)

    Mihaela Mihai

    2015-06-01

    Full Text Available Poverty and social exclusion represent one of the most important themes in contemporary social policy both in UE countries and the rest of the world. In order to combat this and to improve the inclusion rate among NEET youth the social policies need to be channeled in three directions: education, training and employment. This study allows us a broad view of the proposed policies based on the analysis of this indicator.

  6. Organização de práticas de saúde equânimes em atenção primária em região metropolitana no contexto dos processos de inclusão e exclusão social Organization of equanimous practices in primary health attention within the metropolitan area with respect to social inclusion and exclusion processes

    Directory of Open Access Journals (Sweden)

    Nivaldo Carneiro Junior

    2006-12-01

    city of Sao Paulo. The social transformations observed in the region are complex, marked by the heterogeneity of the population groups within the social inclusion/exclusion processes. Inclusion through social policies is an essential item of integration policies, guided by the need to decrease social inequalities. It is necessary to organize work processes that give visibility to these social groups and incorporate their demands into health care, linking them to other social practices. For this aim, primary health care services are ideal. Barra Funda Educational Health Center organized work processes to provide visibility and differentiated attention to these segments. During this process, some groups became visible and were included in health care: the street population; the sex professionals in the region of Luz; the Bolivian immigrants and those living in shantytowns. As part of its technology, the service incorporated the health care of differentiated groups of the population in general, individualizing them, creating specific "entrance doorways", and promoting equanimity in access. Conceptual and methodological challenges were employed in the consolidation of these practices, which required analyses of the social inclusion/exclusion processes, and of the styles of health care, such as integrality and autonomy of the subjects.

  7. Latest Results in Central Exclusive Production: A Summary

    CERN Document Server

    Harland-Lang, L A; Ryskin, M G; Stirling, W J

    2013-01-01

    Selected new results in central exclusive production (CEP) processes within the pQCD-based Durham model are discussed. Topics covered include the CEP of SM and BSM Higgs-like particles, meson pair CEP and the gap survival probability.

  8. 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

    during the 3-D intensification process the convection has not yet organized into annular rings, the azimuthally averaged heating rate and radial gradient thereof is considerably less than that in the AX model. This lack of organization results broadly in a slower intensification rate in the 3-D model and leads ultimately to a weaker mature vortex after 12 days of model integration. While azimuthal mean heating rates in the 3-D model are weaker than those in the AX model, local heating rates in the 3-D model exceed those in the AX model and at times the vortex in the 3-D model intensifies more rapidly than AX. Analyses of the 3-D model output do not support a recent hypothesis concerning the key role of small-scale vertical mixing processes in the upper-tropospheric outflow in controlling the intensification process. In the 3-D model, surface drag plays a particularly important role in the intensification process for the prototype intensification problem on meteorologically relevant timescales by helping foster the organization of convection in azimuth. There is a radical difference in the behaviour of the 3-D and AX simulations when the surface drag is reduced or increased from realistic values. Borrowing from ideas developed in a recent paper, we give a partial explanation for this difference in behaviour. Our results provide new qualitative and quantitative insight into the differences between the asymmetric and symmetric dynamics of tropical cyclones and would appear to have important consequences for the formulation of a fluid dynamical theory of tropical cyclone intensification and mature intensity. In particular, the results point to some fundamental limitations of strict axisymmetric theory and modelling for representing the azimuthally averaged behaviour of tropical cyclones in three dimensions.

  9. Asymmetric and axisymmetric dynamics of tropical cyclones

    Directory of Open Access Journals (Sweden)

    J. Persing

    2013-05-01

    into annular rings, the azimuthally-averaged heating rate and radial gradient thereof is considerably less than that in the AX model. This lack of organization results broadly in a slower intensification rate in the 3-D model and leads ultimately to a weaker mature vortex after 12 days of model integration. While axisymmetric heating rates in the 3-D model are weaker than those in the AX model, local heating rates in the 3-D model exceed those in the AX model and at times the vortex in the 3-D model intensifies more rapidly than AX. Analyses of the 3-D model output do not support a recent hypothesis concerning the key role of small-scale vertical mixing processes in the upper-tropospheric outflow in controlling the intensification process. In the 3-D model, surface drag plays a particularly important role in the intensification process for the prototype intensification problem on meteorologically relevant time scales by helping foster the organization of convection in azimuth. There is a radical difference in the behaviour of the 3-D and AX simulations when the surface drag is reduced or increased from realistic values. Borrowing from ideas developed in a recent paper, we give a partial explanation for this difference in behaviour. Our results provide new qualitative and quantitative insight into the differences between the asymmetric and symmetric dynamics of tropical cyclones and would appear to have important consequences for the formulation of a fluid dynamical theory of tropical cyclone intensification and mature intensity. In particular, the results point to some fundamental limitations of strict axisymmetric theory and modelling for representing the azimuthally-averaged behaviour of tropical cyclones in three dimensions.

  10. 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.

  11. 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)

  12. 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.

  13. 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.

  14. 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

  15. 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....

  16. 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.

  17. 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).

  18. 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…

  19. 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

  20. 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

  1. 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.

  2. Hybrid Asymmetric Space Vector Modulation for inverter based direct torque control induction motor drive

    Directory of Open Access Journals (Sweden)

    Nandakumar Sundararaju

    2014-05-01

    Full Text Available This paper proposes novel hybrid asymmetric space vector modulation technique for inverter operated direct torque control induction motor drive. The hybridization process is performed by the combination of continuous asymmetric space vector modulation pulse width technique (ASVPWM and fuzzy operated discontinuous ASVPWM technique. Combination process is based on pulse mismatching technique. Pulse mismatching technique helps to reduce the active region of the switch. Finally, optimal pulses are applied to control the inverter. The optimal hybrid pulse condense switching losses of the inverter and also improves the operating performance of the direct torque control (DTC based drive system like smooth dynamic response in speed reversal, minimum torque error, settling time of speed. Simulation results of proposed hybrid asymmetric space vector pulse width modulation technique to direct torque control (HASVPWM-DTC approach has been carried out by using Matlab-Simulink environment.

  3. 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...

  4. 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...

  5. 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

  6. Asymmetric Tyrosine Kinase Arrangements in Activation or Autophosphorylation of Receptor Tyrosine Kinases

    Energy Technology Data Exchange (ETDEWEB)

    J Bae; J Schlessinger

    2011-12-31

    Receptor tyrosine kinases (RTKs) play important roles in the control of many cellular processes including cell proliferation, cell adhesion, angiogenesis, and apoptosis. Ligand-induced dimerization of RTKs leads to autophosphorylation and activation of RTKs. Structural studies have shown that while isolated ectodomains of several RTKs form symmetric dimers the isolated cytoplasmic kinase domains of epidermal growth factor receptor (EGFR) and fibroblast growth factor receptor (FGFR) form asymmetric dimers during their activation. Binding of one kinase molecule of EGFR to a second kinase molecule asymmetrically leads to stimulation of kinase activity and enhanced autophosphorylation. Furthermore, the structures of the kinase domain of FGFR1 and FGFR2 reveal the formation of asymmetric interfaces in the processes of autophosphorylation at their specific phosphotyrosine (pY) sites. Disruption of asymmetric dimer interface of EGFR leads to reduction in enzymatic activity and drastic reduction of autophosphorylation of FGFRs in ligandstimulated live cells. These studies demonstrate that asymmetric dimer formation is as a common phenomenon critical for activation and autophosphorylation of RTKs.

  7. Is Amino-Acid Homochirality Due To Asymmetric Photolysis In Space?

    CERN Document Server

    Cerf, C

    1999-01-01

    Amino acids occurring in proteins are, with rare exceptions, exclusively of the L-configuration. Among the many scenarios put forward to explain the origin of this chiral homogeneity (i.e., homochirality), one involves the asymmetric photolysis of amino acids present in space, triggered by circularly polarized UV radiation. The recent observation of circularly polarized light (CPL) in the Orion OMC-1 star-forming region (Bailey et al. 1998, Science 281, 672) has been presented as providing a strong validation of this scenario. The present paper reviews the situation. It is stressed for example that one important condition for the asymmetric photolysis by CPL to be at the origin of the terrestrial homochirality of natural amino acids is generally overlooked, namely, the asymmetric photolysis should favour the L-enantiomer for ALL the primordial amino acids involved in the genesis of life (i.e., biogenic amino acids). Although this condition is probably satisfied for aliphatic amino acids, some non-aliphatic am...

  8. 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....

  9. CERN Summer Student Project: Central Exclusive Diffraction and Glueball Searches

    CERN Document Server

    van Beest, Marieke

    2016-01-01

    CERN Summer Student work project report on work conducted in the Diffraction group at the ALICE experiment as well as the obtained results. These include a kinematical calculation with respect to a generic central exclusive process, the selection rules for a centrally produced system with respect to a specific central exclusive diffraction process, and finally a case study of one of the first contributions to the search for glueballs at CERN.

  10. Process to remove turbidity-causing components from a fluid by micro-filtration - passes the fluid across an asymmetric membrane with inlet pores larger than those of nominal size, and cleans the membrane by backwashing

    DEFF Research Database (Denmark)

    1995-01-01

    turbidity-causing components from beer, wine, fruit juice, milk and blood, and from bacterial and enzyme suspensions. ADVANTAGE-The process greatly reduces the lost production time associated with earlier filtration methods, and beneficial components can pass through the membrane, thereby improving...

  11. Concise Review: Asymmetric Cell Divisions in Stem Cell Biology

    Directory of Open Access Journals (Sweden)

    Florian Murke

    2015-11-01

    Full Text Available Somatic stem cells are rare cells with unique properties residing in many organs and tissues. They are undifferentiated cells responsible for tissue regeneration and homeostasis, and contain both the capacity to self-renew in order to maintain their stem cell potential and to differentiate towards tissue-specific, specialized cells. However, the knowledge about the mechanisms controlling somatic stem cell fate decisions remains sparse. One mechanism which has been described to control daughter cell fates in selected somatic stem cell systems is the process of asymmetric cell division (ACD. ACD is a tightly regulated and evolutionary conserved process allowing a single stem or progenitor cell to produce two differently specified daughter cells. In this concise review, we will summarize and discuss current concepts about the process of ACD as well as different ACD modes. Finally, we will recapitulate the current knowledge and our recent findings about ACD in human hematopoiesis.

  12. Perfil dos internos no sistema prisional do Rio de Janeiro: especificidades de gênero no processo de exclusão social Profile of prisoners in the Rio de Janeiro prison system: specifities of gender in the social exclusion process

    Directory of Open Access Journals (Sweden)

    Márcia Lazaro de Carvalho

    2006-06-01

    Full Text Available O estudo do perfil sociodemográfico, história penal, uso de drogas e doenças sexualmente transmissíveis da população carcerária do Estado do Rio de Janeiro, em 1998, permitiu conhecer diferentes características da população prisional por sexo. O objetivo deste estudo é identificar se o perfil de exclusão social a que essa população é submetida difere quanto ao sexo. Foram entrevistados 2.039 presos por estudo seccional, e utilizada a razão de prevalência como medida de associação entre sexo e as demais variáveis. A análise multivariada, através de regressão logística, compõe um modelo final de explicação dessas diferenças. A população é jovem, de baixa escolaridade, e apresenta ruptura de vínculos da vida social em várias dimensões para ambos os sexos. Fatores mais fortemente associados ao sexo masculino: visita íntima na prisão, estar preso por sete anos ou mais, ser casado, condenação por roubo, ter ainda três anos ou mais a cumprir de pena e uso de maconha antes de ser preso; para o sexo feminino: doença sexualmente transmissível, ser viúva, estrangeira, usar tranqüilizante na prisão, ter visitado alguém na prisão antes de ser presa e ter 35 anos ou mais. A análise dos dados permitiu concluir que embora esses homens e mulheres sejam igualmente excluídos da "vida social" muito antes e também depois da prisão, existem algumas características que os diferenciam nesse processo de injustiça social.The study of the social and demographic profile, criminal records, drug use and sexually transmitted diseases of the prison population of Rio de Janeiro State in 1998 offered a view of different aspects of this population by gender. The objective of this study is to identify if the profile of social exclusion this population is submitted differs by gender. Through a sectional study, 2,039 prisoners were interviewed, using the prevalence ratio as an association measure between gender and the other

  13. Exclusive dimuon measurements with LHCb

    CERN Document Server

    Shears, Tara

    2011-01-01

    A measurement of exclusive dimuon production provides a clean test of QED and QCD predictions in a low multiplicity environment. Exclusively produced dimuon pairs can be produced by two photon fusion, or through resonances produced by pomeron-photon fusion or double pomeron exchange. We present cross-section measurements for exclusive dimuon production, and the first observations at a proton proton collider of exclusive J/$\\psi$, $\\psi(2S)$ and $\\chi_c$ states, obtained with 37 pb$^{-1}$ of data at a centre-of-mass energy of 7 TeV, collected by the LHCb experiment.

  14. Hydrodynamic Limit For An Active Exclusion Process

    OpenAIRE

    Clément, Erignoux

    2016-01-01

    Collective dynamics can be observed among many animal species, and have given rise in the last decades to an active and interdisciplinary field of study. Such behaviors are often modeled by active matter, in which each individual is self-driven and tends to update its velocity depending on the one of its neighbors. In a classical model introduced by Vicsek \\and al., as well as in numerous related active matter models, a phase transition between chaotic behavior at high temperature and global ...

  15. Direct Asymmetric Aldol Type Reaction with Ethyl Diazoacetate: Stereoselective Synthesis of α, β-Dihydroxy Esters

    Institute of Scientific and Technical Information of China (English)

    LIAO Ming-Yi; YAO Wen-Gang; FENG Hai-Tao; WANG Jian-Bo

    2003-01-01

    @@ Enantioselective aldol condensation under catalytic condition remains a challenging task in modern organic synthesis, and numerous efforts have been directed to this area. In particular, the direct catalytic asymmetric aldol reaction is very attractive considering the requirement of atom efficiency. This has been studied only recently, and several very practical processes have been developed. We have recently initiated a study on the direct asymmetric aldol type reaction with ethyl diazoacetate as nucleophile. Moderate enantioselectivities (65% ~91% ee ) were achieved in the condensation of aldehydes with ethyl diazoacetate catalyzed by the chiral complex of BINOL derivatives-Zr (OBu- t )4. [1

  16. 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.

  17. Asymmetric Magnetic Reconnection in Solar Flare and Coronal Mass Ejection Current Sheets

    CERN Document Server

    Murphy, N A; Pope, C L; Raymond, J C; Winter, H D; Reeves, K K; Seaton, D B; van Ballegooijen, A A; Lin, J

    2012-01-01

    We present two-dimensional resistive magnetohydrodynamic simulations of line-tied asymmetric magnetic reconnection in the context of solar flare and coronal mass ejection current sheets. The reconnection process is made asymmetric along the inflow direction by allowing the initial upstream magnetic field strengths and densities to differ, and along the outflow direction by placing the initial perturbation near a conducting wall boundary that represents the photosphere. When the upstream magnetic fields are asymmetric, the post-flare loop structure is distorted into a characteristic skewed candle flame shape. The simulations can thus be used to provide constraints on the reconnection asymmetry in post-flare loops. More hard X-ray emission is expected to occur at the footpoint on the weak magnetic field side because energetic particles are more likely to escape the magnetic mirror. The footpoint on the weak magnetic field side is predicted to move more quickly because of the requirement in two dimensions that e...

  18. 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.

  19. 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.

  20. 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.

  1. 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...

  2. 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...

  3. 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.

  4. 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...

  5. 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...

  6. 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...

  7. 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

  8. 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...

  9. 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...

  10. 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."

  11. 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.

  12. 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 ...

  13. 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...

  14. 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.

  15. 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...

  16. 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...

  17. 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.

  18. 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...

  19. 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.

  20. 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.

  1. Niche-associated activation of rac promotes the asymmetric division of Drosophila female germline stem cells.

    Directory of Open Access Journals (Sweden)

    Wen Lu

    Full Text Available BACKGROUND: Drosophila female germline stem cells (GSCs reside adjacent to a cellular niche that secretes Bone Morphogenetic Protein (BMP ligands and anchors the GSCs through adherens junctions. The GSCs divide asymmetrically such that one daughter remains in the niche as a GSC, while the other is born away from the niche and differentiates. However, given that the BMP signal can be diffusible, it remains unclear how a local extracellular asymmetry is sufficient to result in a robust pattern of asymmetric division. METHODS AND FINDINGS: Here we show that GSCs are polarized with respect to the cellular niche. We first use a modified biosensor to demonstrate that the small GTPase Rac is asymmetrically activated within the GSC at the niche-GSC interface. Experiments using loss-of-function and gain-of-function mutations in Rac indicate that asymmetric Rac activity both localizes the microtubule binding protein Apc2 to orient one GSC centrosome at the niche-GSC interface during interphase and activates the Jun N-terminal kinase pathway to increase the ability of the GSC to respond to BMP ligands. Other processes act in concert with each function of Rac. Specifically, we demonstrate that the GSC cell cycle arrests at prometaphase if centrosomes are misoriented. CONCLUSIONS: Thus, the GSCs, an adult stem cell present in a cellular niche, have a niche-associated polarity that couples control of the division plane with increased response to an extracellular maintenance signal. Other processes work in parallel with the Rac-mediated polarity to ensure a robust pattern of asymmetric division. We suggest that all adult stem cells likely employ multiple, independently acting mechanisms to ensure asymmetric division to maintain tissue homeostasis.

  2. Orientation of the X-line in asymmetric magnetic reconnection

    Science.gov (United States)

    Aunai, N.; Hesse, M.; Lavraud, B.; Dargent, J.; Smets, R.

    2016-08-01

    > Magnetic reconnection can occur in current sheets separating magnetic fields sheared by any angle and of arbitrarily different amplitudes. In such asymmetric and non-coplanar systems, it is not yet understood what the orientation of the X-line will be. Studying how this orientation is determined locally by the reconnection process is important to understand systems such as the Earth magnetopause, where reconnection occurs in regions with large differences in upstream plasma and field properties. This study aims at determining what the local X-line orientation is for different upstream magnetic shear angles in an asymmetric set-up relevant to the Earth's magnetopause. We use two-dimensional hybrid simulations and vary the simulation plane orientation with regard to the fixed magnetic field profile and search for the plane maximizing the reconnection rate. We find that the plane defined by the bisector of upstream fields maximizes the reconnection rate and this appears not to depend on the magnetic shear angle, domain size or upstream plasma and asymmetries.

  3. Corporate governance ratings as a means to reduce asymmetric information

    Directory of Open Access Journals (Sweden)

    Claus Holm

    2014-12-01

    Full Text Available Can corporate governance ratings reduce problems of asymmetric information between companies and investors? To answer this question, we set out to examine the information basis for providing such ratings by reviewing corporate governance attributes that are required or recommended in laws, accounting standards, and codes, respectively. After that, we scrutinize and organize the publicly available information on the methodologies actually used by rating providers. However, important details of these methodologies are treated as confidential property, thus we approach the evaluation of corporate governance ratings as a means to reduce asymmetric information in a more general manner. We propose that the rating process may be seen as consisting of two general activities, namely a data reduction phase, and a data weighting, aggregation, and classification phase. Findings based on a Danish data-set suggest that rating providers by selecting relevant attributes in an intelligent way can improve the screening of companies according to governance quality. In contrast, it seems questionable that weighting, aggregation, and classification of corporate governance attributes considerably improve discrimination according to governance quality.

  4. Asymmetric Supernovae, Pulsars, Magnetars, and Gamma-Ray Bursts

    CERN Document Server

    Wheeler, J C; Höflich, P; Wang, L; Yi, Insu; Hoeflich, Peter; Wang, Lifan

    1999-01-01

    We outline the possible physical processes, associated timescales, and energetics that could lead to the production of pulsars, jets, asymmetric supernovae, and weak gamma-ray bursts in routine circumstances and to a magnetar and perhaps stronger gamma-ray burst in more extreme circumstances in the collapse of the bare core of a massive star. The production of a LeBlanc-Wilson MHD jet could provide an asymmetric supernova and result in a weak gamma-ray burst when the jet accelerates down the stellar density gradient of a hydrogen-poor photosphere. The matter-dominated jet would be formed promptly, but requires 5 to 10 s to reach the surface of the progenitor of a Type Ib/c supernova. During this time, the newly-born neutron star could contract, spin up, and wind up field lines or turn on an $\\alpha-\\Omega$ dynamo. In addition, the light cylinder will contract from a radius large compared to the Alfvén radius to a size comparable to that of the neutron star. This will disrupt the structure of any organized di...

  5. Asymmetric switching in a homodimeric ABC transporter: a simulation study.

    Directory of Open Access Journals (Sweden)

    Jussi Aittoniemi

    2010-04-01

    Full Text Available ABC transporters are a large family of membrane proteins involved in a variety of cellular processes, including multidrug and tumor resistance and ion channel regulation. Advances in the structural and functional understanding of ABC transporters have revealed that hydrolysis at the two canonical nucleotide-binding sites (NBSs is co-operative and non-simultaneous. A conserved core architecture of bacterial and eukaryotic ABC exporters has been established, as exemplified by the crystal structure of the homodimeric multidrug exporter Sav1866. Currently, it is unclear how sequential ATP hydrolysis arises in a symmetric homodimeric transporter, since it implies at least transient asymmetry at the NBSs. We show by molecular dynamics simulation that the initially symmetric structure of Sav1866 readily undergoes asymmetric transitions at its NBSs in a pre-hydrolytic nucleotide configuration. MgATP-binding residues and a network of charged residues at the dimer interface are shown to form a sequence of putative molecular switches that allow ATP hydrolysis only at one NBS. We extend our findings to eukaryotic ABC exporters which often consist of two non-identical half-transporters, frequently with degeneracy substitutions at one of their two NBSs. Interestingly, many residues involved in asymmetric conformational switching in Sav1866 are substituted in degenerate eukaryotic NBS. This finding strengthens recent suggestions that the interplay of a consensus and a degenerate NBS in eukaroytic ABC proteins pre-determines the sequence of hydrolysis at the two NBSs.

  6. Fourier domain asymmetric cryptosystem for privacy protected multimodal biometric security

    Science.gov (United States)

    Choudhury, Debesh

    2016-04-01

    We propose a Fourier domain asymmetric cryptosystem for multimodal biometric security. One modality of biometrics (such as face) is used as the plaintext, which is encrypted by another modality of biometrics (such as fingerprint). A private key is synthesized from the encrypted biometric signature by complex spatial Fourier processing. The encrypted biometric signature is further encrypted by other biometric modalities, and the corresponding private keys are synthesized. The resulting biometric signature is privacy protected since the encryption keys are provided by the human, and hence those are private keys. Moreover, the decryption keys are synthesized using those private encryption keys. The encrypted signatures are decrypted using the synthesized private keys and inverse complex spatial Fourier processing. Computer simulations demonstrate the feasibility of the technique proposed.

  7. Low Viscosity Imides Based on Asymmetric Oxydiphthalic Anhydride

    Science.gov (United States)

    Chuang, Kathy C.; Criss, Jim M., Jr.; Mintz, Eric A.; Scheiman, Daniel A.; Nguyen, Baochau N.; McCorkle, Linda S.

    2008-01-01

    A series of low-melt viscosity imide resins were prepared from asymmetric oxydiphthalic dianhydride (a-ODPA) and 4-phenylethynylphthalic anhydride as the endcap, along with 3,4' - oxydianiline (3,4' -ODA), 3,4' -methylenedianiline (3,4' -MDA), 3,3' -methylenedianiline (3,3' - MDA) and 3,3'-diaminobenzophenone (3,3'-DABP), using a solvent-free melt process. These imide oligomers displays low-melt viscosities (2-15 poise) at 260-280 C, which made them amenable to low-cost resin transfer molding (RTM) process. The a-ODPA based RTM resins exhibits glass transition temperatures (Tg's) in the range of 265-330 C after postcure at 343 C. The mechanical properties of these polyimide/carbon fiber composites fabricated by RTM will be discussed.

  8. Exclusive pi^+ production at HERMES

    OpenAIRE

    C. Hadjidakis; Hasch, D.; Thomas, E.; collaboration, for the HERMES

    2004-01-01

    Hard exclusive production in deep inelastic lepton scattering provides access to the unknown Generalized Parton Distributions (GPDs) of the nucleon. At HERMES, different observables for hard exclusive pi^+ production have been measured with a 27.6 GeV positron beam on an internal hydrogen gas target. First preliminary results for the unpolarized ep->enpi^+ total cross section for 1.5

  9. Exclusion Statistics: a Generalized Description

    Institute of Scientific and Technical Information of China (English)

    WANG Bao-Quan; WANG Yu-Peng

    2005-01-01

    @@ By constructing the fused-particle representation of the free boson gas, we propose a description of the exclusion statistics which allows us to connect the Bose-Einstein statistics and the Fermi-Dirac statistics smoothly.With an proper choice of the exclusion factors γl, Hadane-Wu's fractional statistics is retrieved in this representation.

  10. Abnormal Neural Responses to Social Exclusion in Schizophrenia

    OpenAIRE

    Gradin, Victoria B.; Gordon Waiter; Poornima Kumar; Catriona Stickle; Maarten Milders; Keith Matthews; Ian Reid; Jeremy Hall; J Douglas Steele

    2012-01-01

    Social exclusion is an influential concept in politics, mental health and social psychology. Studies on healthy subjects have implicated the medial prefrontal cortex (mPFC), a region involved in emotional and social information processing, in neural responses to social exclusion. Impairments in social interactions are common in schizophrenia and are associated with reduced quality of life. Core symptoms such as delusions usually have a social content. However little is known about the neural ...

  11. Métodos heurísticos construtivos para redução do estoque em processo em ambientes de produção flow shop híbridos com tempos de setup dependentes da sequência Constructive heuristics methods to minimizing work in process in environment production hybrid flow shop with asymmetric sequence dependent setup times

    Directory of Open Access Journals (Sweden)

    Márcia de Fátima Morais

    2010-01-01

    Full Text Available Este artigo apresenta uma investigação sobre o problema de programação da produção em ambientes flow shop com múltiplas máquinas (híbridos e tempos de preparação (setup das máquinas assimétricos e dependentes da sequência, e propõe métodos heurísticos construtivos para a minimização do tempo médio de fluxo (Mean Flow Time, que objetiva uma resposta rápida à demanda e à redução do estoque em processamento. Os algoritmos propostos foram comparados entre si, uma vez que nenhum método de solução para o problema investigado foi encontrado na literatura. Um estudo da influência da relação entre as ordens de grandeza dos tempos de processamento das tarefas e de preparação das máquinas em cada método de solução, bem como a influência do procedimento de programação adotado, foi efetuado com o intuito de avaliar o desempenho dos métodosThis paper presents an investigation about the hybrid flow shop problem with asymmetric sequence dependent setup times and proposes constructive heuristic methods to minimize the mean flow time aiming at fast demand response and work in process reduction. The proposed heuristic methods were compared among themselves since no constructive heuristic method was found in the literature on the scheduling problem considered in this work. A study on the influence of the relation between the orders of magnitude of processing and setup time for each method was carried out. The influence of the scheduling procedure adopted was investigated to assess the performance of the methods use

  12. Diffractive and Exclusive Measurements at CMS

    CERN Document Server

    Ruspa, Marta

    2014-01-01

    Recent measurements are discussed of inclusive and exclusive diffractive processes in pp colli- sions at √ s = 7 TeV at the LHC using the CMS detector. Results are presented of the single- and double-diffractive cross section and of the inclusive differential cross section for events with a forward rapidity gap. A study of exclusive W + W − production by two-photon exchange, where, in different kinematic regions, both con fi rmation and deviations from the Standard Model predic- tions are searched, is reported. Finally, a joint measurement with the CMS and TOTEM detectors of the pseudorapidity distribution of charged particles produced in pp collisions at √ s = 8 TeV is presented. This is the fi rst joint study between the two experiments.

  13. A study of Central Exclusive Production

    Energy Technology Data Exchange (ETDEWEB)

    Monk, James; /Manchester U.

    2008-09-01

    Central exclusive production of a system X in a collision between two hadrons h is defined as hh {yields} h + X + h with no other activity apart from the decay products of X. This thesis presents predictions for the production cross section of a CP violating supersymmetric Higgs boson and the radion of the Randall-Sundrum model. The ExHuME Monte Carlo generator was written to simulate central exclusive processes and is described and explored. A comparison to di-jet observations made by the D0 detector at the Tevatron, Fermilab between January and June 2004 is made and the distributions found support the predictions of ExHuME.

  14. Exclusive vector meson production at HERMES

    Directory of Open Access Journals (Sweden)

    Movsisyan Aram

    2014-06-01

    Full Text Available Exclusive electroproduction of vector mesons has been measured on hydrogen and deuterium targets at HERMES using the 27.6 GeV electron/positron beam of HERA. From this process, more information can be obtained about generalized parton distributions (GPDs, which provide a unified description of the structure of hadrons embedding longitudinal-momentum distributions (ordinary PDFs and transverse-position information (form factors. The study of the azimuthal distribution of the decay products via spin-density matrix elements provide constraints on helicity-amplitudes used to describe exclusive vector-meson production. Recent results from the HERMES experiment on the production of rho, omega and phi mesons will be presented.

  15. Exclusive vector meson production at HERMES

    Science.gov (United States)

    Movsisyan, Aram

    2014-06-01

    Exclusive electroproduction of vector mesons has been measured on hydrogen and deuterium targets at HERMES using the 27.6 GeV electron/positron beam of HERA. From this process, more information can be obtained about generalized parton distributions (GPDs), which provide a unified description of the structure of hadrons embedding longitudinal-momentum distributions (ordinary PDFs) and transverse-position information (form factors). The study of the azimuthal distribution of the decay products via spin-density matrix elements provide constraints on helicity-amplitudes used to describe exclusive vector-meson production. Recent results from the HERMES experiment on the production of rho, omega and phi mesons will be presented.

  16. Centralized and decentralized global outer-synchronization of asymmetric recurrent time-varying neural network by data-sampling.

    Science.gov (United States)

    Lu, Wenlian; Zheng, Ren; Chen, Tianping

    2016-03-01

    In this paper, we discuss outer-synchronization of the asymmetrically connected recurrent time-varying neural networks. By using both centralized and decentralized discretization data sampling principles, we derive several sufficient conditions based on three vector norms to guarantee that the difference of any two trajectories starting from different initial values of the neural network converges to zero. The lower bounds of the common time intervals between data samples in centralized and decentralized principles are proved to be positive, which guarantees exclusion of Zeno behavior. A numerical example is provided to illustrate the efficiency of the theoretical results.

  17. 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.

  18. Problems of Chernobyl Exclusion Zone

    International Nuclear Information System (INIS)

    The collection comprises the results of researches and design activity in the ChNPP exclusion zone, aimed at the development of technologies, equipment and devices for radioactive waste management and ChNPP accident clean-up, at studying the composition and structure of the Exclusion zone soil activity solid bearers, form transformation of the fission products of fuel fallout radionuclide composition in the ChNPP near zone, the spatial distribution of radionuclides and other radioecological issues.. Much attention is paid to medical and biological aspects of the accident influence on the flora, fauna and people's health, labour conditions and incidence of the workers of the Exclusion zone

  19. 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.

  20. 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.

  1. 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.

  2. 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

  3. 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.

  4. 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.

  5. 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....

  6. 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.

  7. 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

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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...

  14. 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.

  15. 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.

  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

    2016-07-25

    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

  17. 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.

  18. 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.

  19. Lithium Titanate Confined in Carbon Nanopores for Asymmetric Supercapacitors.

    Science.gov (United States)

    Zhao, Enbo; Qin, Chuanli; Jung, Hong-Ryun; Berdichevsky, Gene; Nese, Alper; Marder, Seth; Yushin, Gleb

    2016-04-26

    Porous carbons suffer from low specific capacitance, while intercalation-type active materials suffer from limited rate when used in asymmetric supercapacitors. We demonstrate that nanoconfinement of intercalation-type lithium titanate (Li4Ti5O12) nanoparticles in carbon nanopores yielded nanocomposite materials that offer both high ion storage density and rapid ion transport through open and interconnected pore channels. The use of titanate increased both the gravimetric and volumetric capacity of porous carbons by more than an order of magnitude. High electrical conductivity of carbon and the small size of titanate crystals allowed the composite electrodes to achieve characteristic charge and discharge times comparable to that of the electric double-layer capacitors. The proposed composite synthesis methodology is simple, scalable, and applicable for a broad range of active intercalation materials, while the produced composite powders are compatible with commercial electrode fabrication processes. PMID:26950509

  20. CUSP CATASTROPHE MODEL OF INSTABILITY OF PILLAR IN ASYMMETRIC MINING

    Institute of Scientific and Technical Information of China (English)

    LI Jiang-teng; CAO Ping

    2005-01-01

    A simplified mechanical model of pillar-hang wall was established in asymmetric mining and instability of the system was discussed by means of potential energy principle and cusp catastrophe theory. The necessary-sufficient condition and the jump value of displacement of pillar and the released energy expressions were derived,which established foundation for quantifying of the instability of system. The results show that instability of the system is related to load and its stiffness distribution. The critical load increases with the increasing relative stiffness, and the system is more stable. On the contrary, the instability of system is likely to occur, and the released energy is larger in instability process, and the harm is more tremendous accordingly.Furthermore, an example was calculated, and the estimated results are in good agreement with the practical experience, which provide basis for mining order and arranging stope.

  1. 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.

  2. Contrasting Stories of Inclusion/Exclusion in the Chemistry Classroom

    Science.gov (United States)

    de Fátima Cardoso Gomes, Maria; Mortimer, Eduardo F.; Kelly, Gregory J.

    2011-04-01

    This article reports on the construction process of inclusion/exclusion for high school chemistry students in two schools in Belo Horizonte, the capital of Minas Gerais State, Brazil. We examined the interactional accomplishment of inclusion/exclusion of four students, two from a private school and two from a public school. The aim of this article is to describe these students' stories of inclusion/exclusion and to discuss what motivated them to learn chemistry in the classrooms investigated. To learn chemistry, students need to develop an individual understanding of the social language of the discipline. Inclusion/exclusion is accomplished interactively as members of different communities make choices about how to participate, involve others, and direct their actions. Such interactions are mediated by the teacher, and thus, through discourse, the collective group establishes certain learning opportunities.

  3. 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.

  4. 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.

  5. Postglacial species displacement in Triturus newts deduced from asymmetrically introgressed mitochondrial DNA and ecological niche models

    Directory of Open Access Journals (Sweden)

    Wielstra Ben

    2012-08-01

    Full Text Available Abstract Background If the geographical displacement of one species by another is accompanied by hybridization, mitochondrial DNA can introgress asymmetrically, from the outcompeted species into the invading species, over a large area. We explore this phenomenon using the two parapatric crested newt species, Triturus macedonicus and T. karelinii, distributed on the Balkan Peninsula in south-eastern Europe, as a model. Results We first delimit a ca. 54,000 km2 area in which T. macedonicus contains T. karelinii mitochondrial DNA. This introgression zone bisects the range of T. karelinii, cutting off a T. karelinii enclave. The high similarity of introgressed mitochondrial DNA haplotypes with those found in T. karelinii suggests a recent transfer across the species boundary. We then use ecological niche modeling to explore habitat suitability of the location of the present day introgression zone under current, mid-Holocene and Last Glacial Maximum conditions. This area was inhospitable during the Last Glacial Maximum for both species, but would have been habitable at the mid-Holocene. Since the mid-Holocene, habitat suitability generally increased for T. macedonicus, whereas it decreased for T. karelinii. Conclusion The presence of a T. karelinii enclave suggests that T. karelinii was the first to colonize the area where the present day introgression zone is positioned after the Last Glacial Maximum. Subsequently, we propose T. karelinii was outcompeted by T. macedonicus, which captured T. karelinii mitochondrial DNA via introgressive hybridization in the process. Ecological niche modeling suggests that this replacement was likely facilitated by a shift in climate since the mid-Holocene. We suggest that the northwestern part of the current introgression zone was probably never inhabited by T. karelinii itself, and that T. karelinii mitochondrial DNA spread there through T. macedonicus exclusively. Considering the spatial distribution of the

  6. Returning a stare: people's struggles for political and social inclusion (Social exclusion: an international perspective part 1)

    OpenAIRE

    Durrani, Shiraz

    2000-01-01

    This is the first of two linked working papers analysing social exclusion at an international level (the second being by John Pateman). It reviews struggles against exclusion and poverty in different societies, emphasising the role of information, and the potential of role of libraries. Social exclusion is described in the context of global capitalism. The process of exclusion is seen as having intensified with the rise of the ‘information age.’ The paper then looks at resistance to this exc...

  7. Missing persons and social exclusion

    Directory of Open Access Journals (Sweden)

    Myrna Dawson

    2012-01-01

    Full Text Available The concept of social exclusion is used to explore the relationship between people and groups who may be socially and economically disadvantaged and the phenomenon of going missing. Police data about missing persons are compared to census data to determine whether groups who experience family dissolution, labour market exclusion, and other forms of disadvantage and social exclusion are overrepresented among people reported missing compared to the general population. The analysis shows that disadvantaged youth, women, Aboriginal people, people who are not in the labour force, unemployed people, and homeless people are all overrepresented among people reported missing.People occupying the intersections of multiple high risk categories are at particularly high risk of being reported missing. Linking missing persons with the concept of social exclusion shows that social and economic disadvantage can lead directly and indirectly to peoples’ disappearances.

  8. 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

  9. 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.

  10. 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.

  11. 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.

  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. 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

  14. 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...

  15. 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)

  16. 47 CFR 76.107 - Exclusivity contracts.

    Science.gov (United States)

    2010-10-01

    ... CABLE TELEVISION SERVICE Network Non-duplication Protection, Syndicated Exclusivity and Sports Blackout § 76.107 Exclusivity contracts. A distributor or television station exercising exclusivity pursuant to... exclusivity contracts, such portions to be signed by both the distributor and the television station,...

  17. 提高女大学生就业能力的必要性及价值分析%Social Exclusion Condition Investigation in Female College Students' Employment Process

    Institute of Scientific and Technical Information of China (English)

    张亚强; 梁彦红

    2012-01-01

    To understand the current employment status of female students, this paper analyzed the main reason for "the difficult employment" and social exclusion of female college students, and put forward relevant countermeasures. In the survey on female college students' employment, it found that the girls were more difficult to get a job than boys and the biggest harder that girls faced was sex discrimination and social exclusion. Government departments, the employer and the schools should adopt positive improvement measures to help female college students' employment and reduce social exclusion.%为把握了解当前女大学生的就业现状,分析女大学生“就业难”和社会排挤的主要原因,研究分析并提出相关对策建议,我们对某高校女大学生就业情况进行问卷调查.调查中我们发现就业过程中确实存在女生比男生更难就业,女生就业面临的最大困难就是性别歧视和社会排挤.政府部门、用人单位与学校应采用积极的改进措施帮助女大学生就业和减少社会排挤.

  18. Immobilization of Acetobacter sp. CCTCC M209061 for efficient asymmetric reduction of ketones and biocatalyst recycling

    Directory of Open Access Journals (Sweden)

    Chen Xiao-Hong

    2012-09-01

    Full Text Available Abstract Background The bacterium Acetobacter sp. CCTCC M209061 is a promising whole-cell biocatalyst with exclusive anti-Prelog stereoselectivity for the reduction of prochiral ketones that can be used to make valuable chiral alcohols such as (R-4-(trimethylsilyl-3-butyn-2-ol. Although it has promising catalytic properties, its stability and reusability are relatively poor compared to other biocatalysts. Hence, we explored various materials for immobilizing the active cells, in order to improve the operational stability of biocatalyst. Results It was found that Ca-alginate give the best immobilized biocatalyst, which was then coated with chitosan to further improve its mechanical strength and swelling-resistance properties. Conditions were optimized for formation of reusable immobilized beads which can be used for repeated batch asymmetric reduction of 4′-chloroacetophenone. The optimized immobilized biocatalyst was very promising, with a specific activity of 85% that of the free-cell biocatalyst (34.66 μmol/min/g dw of cells for immobilized catalyst vs 40.54 μmol/min/g for free cells in the asymmetric reduction of 4′-chloroacetophenone. The immobilized cells showed better thermal stability, pH stability, solvent tolerance and storability compared with free cells. After 25 cycles reaction, the immobilized beads still retained >50% catalytic activity, which was 3.5 times higher than degree of retention of activity by free cells reused in a similar way. The cells could be recultured in the beads to regain full activity and perform a further 25 cycles of the reduction reaction. The external mass transfer resistances were negligible as deduced from Damkohler modulus Da η ∅ Conclusions Ca-alginate coated with chitosan is a highly effective material for immobilization of Acetobacter sp. CCTCC M209061 cells for repeated use in the asymmetric reduction of ketones. Only a small cost in terms of the slightly lower catalytic activity compared to

  19. Collocation method for the solution of the neutron transport equation with both symmetric and asymmetric scattering

    Energy Technology Data Exchange (ETDEWEB)

    Morel, J.E.

    1981-01-01

    A collocation method is developed for the solution of the one-dimensional neutron transport equation in slab geometry with both symmetric and polarly asymmetric scattering. For the symmetric scattering case, it is found that the collocation method offers a combination of some of the best characteristics of the finite-element and discrete-ordinates methods. For the asymmetric scattering case, it is found that the computational cost of cross-section data processing under the collocation approach can be significantly less than that associated with the discrete-ordinates approach. A general diffusion equation treating both symmetric and asymmetric scattering is developed and used in a synthetic acceleration algorithm to accelerate the iterative convergence of collocation solutions. It is shown that a certain type of asymmetric scattering can radically alter the asymptotic behavior of the transport solution and is mathematically equivalent within the diffusion approximation to particle transport under the influence of an electric field. The method is easily extended to other geometries and higher dimensions. Applications exist in the areas of neutron transport with highly anisotropic scattering (such as that associated with hydrogenous media), charged-particle transport, and particle transport in controlled-fusion plasmas. 23 figures, 6 tables.

  20. Asymmetric lipid-polymer particles (LIPOMER) by modified nanoprecipitation: role of non-solvent composition.

    Science.gov (United States)

    Jindal, Anil B; Devarajan, Padma V

    2015-07-15

    Asymmetric lipid polymer nanostructures (LIPOMER) comprising glyceryl monostearate (GMS) as lipid and Gantrez AN 119 (Gantrez) as polymer, revealed enhanced splenic accumulation. In the present paper, we attempt to explain the formation of asymmetric GMS LIPOMER using real time imaging. Particles were prepared by precipitation under static conditions using different non-solvent phase compositions. The process was video recorded and the videos converted to time elapsed images using the FFmpeg 0.10.2 software at 25 frames/sec. Non-solvent compositions comprising >30% of IPA/Acetone revealed significant stranding of the solvent phase and slower onset of precipitation(2-6s). At lower concentrations of IPA and acetone, and in non-solvent compositions comprising ethanol/water the stranding phenomenon was not evident. Further, rapid precipitation(stranding, interfacial turbulence, and mass transfer of solvent and non-solvent resulting in solute precipitation. Enhanced diffusion stranding favored by high interaction of GMS and Gantrez(low ΔPol), and the low solubility parameter(Δδtotal) and high mixing enthalpy(ΔHM) of GMS in IPA resulted in droplets with random shapes analogous to an amoeba with pseudopodia, which on precipitation formed asymmetric particles. Asymmetric particles could be readily designed through appropriate selection of solutes and non-solvent phase by modified nanoprecipitation. PMID:25934429

  1. Development of asymmetric membrane capsules of metformin hydrochloride for oral osmotic controlled drug delivery

    Directory of Open Access Journals (Sweden)

    Venkatesh Teja Banala

    2014-01-01

    Full Text Available Asymmetric membrane capsules are one of the novel osmotic delivery devices which offer the delivery of a wide range of drugs in a controlled manner. In the present work, we developed a semi-automatic process by fabricating a hydraulic assisted mechanical robotic arm for the manufacturing of asymmetric membrane capsules and the process was validated in comparison with the manual procedure of manufacturing. The capsule walls were made by dip coating phase inversion process using cellulose acetate butyrate as polymer and propylene glycol as plasticizer/pore forming agent. The comparative examination of physical parameters in manual and semi-automatic process confirmed the consistency, reproducibility and efficiency of the semi-automatic process over manual procedure. The resulting asymmetric membrane wall was evaluated by scanning electron microscopy studies revealed the thin dense region supported on a thicker porous region. Fourier transform infrared studies showed phase inversion of the asymmetric membrane as compared to plain membrane. Osmotic release study and in vitro behavior was studied for controlled delivery of metformin hydrochloride as a model drug. In vitro release studies of the formulations showed that drug release was dependent on the concentration of pore forming agent, level of osmogents and independent of the media pH and agitation. The effect of the process variables on the drug release was optimized using 2 3 full factorial design and the release kinetics of the optimized formulation confirmed zero order kinetics with a controlled drug delivery of 13 h and the mechanism of drug release was found to be super case II transport.

  2. Theoretical analysis of dynamic processes for interacting molecular motors

    International Nuclear Information System (INIS)

    Biological transport is supported by the collective dynamics of enzymatic molecules that are called motor proteins or molecular motors. Experiments suggest that motor proteins interact locally via short-range potentials. We investigate the fundamental role of these interactions by carrying out an analysis of a new class of totally asymmetric exclusion processes, in which interactions are accounted for in a thermodynamically consistent fashion. This allows us to explicitly connect microscopic features of motor proteins with their collective dynamic properties. A theoretical analysis that combines various mean-field calculations and computer simulations suggests that the dynamic properties of molecular motors strongly depend on the interactions, and that the correlations are stronger for interacting motor proteins. Surprisingly, it is found that there is an optimal strength of interactions (weak repulsion) that leads to a maximal particle flux. It is also argued that molecular motor transport is more sensitive to attractive interactions. Applications of these results for kinesin motor proteins are discussed. (paper)

  3. 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

  4. 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.

  5. 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.

  6. 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.  ……

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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

  12. 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...

  13. 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...

  14. 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.

  15. 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.

  16. 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....

  17. 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....

  18. 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.

  19. 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.

  20. 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...

  1. 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

  2. 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 ...

  3. 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...

  4. Exclusive physics at the LHC with SuperChic 2

    Energy Technology Data Exchange (ETDEWEB)

    Harland-Lang, L.A. [University College London, Department of Physics and Astronomy, London (United Kingdom); Khoze, V.A. [University of Durham, Institute for Particle Physics Phenomenology, Durham (United Kingdom); NRC Kurchatov Institute, Gatchina, Petersburg Nuclear Physics Institute, St. Petersburg (Russian Federation); Ryskin, M.G. [NRC Kurchatov Institute, Gatchina, Petersburg Nuclear Physics Institute, St. Petersburg (Russian Federation)

    2016-01-15

    We present a range of physics results for central exclusive production processes at the LHC, using the new SuperChic 2 Monte Carlo event generator. This includes significant theoretical improvements and updates, most importantly a fully differential treatment of the soft survival factor, as well as a greater number of generated processes. We provide an overview of the latest theoretical framework, and consider in detail a selection of final states, namely exclusive 2 and 3 jets, photoproduced vector mesons, two-photon initiated muon and W boson pairs and heavy χ{sub c,b} quarkonia. (orig.)

  5. Exclusive physics at the LHC with SuperChic 2

    Energy Technology Data Exchange (ETDEWEB)

    Harland-Lang, L. A., E-mail: l.harland-lang@ucl.ac.uk [Department of Physics and Astronomy, University College London, WC1E 6BT, London (United Kingdom); Khoze, V. A. [Institute for Particle Physics Phenomenology, University of Durham, DH1 3LE, Durham (United Kingdom); Petersburg Nuclear Physics Institute, NRC Kurchatov Institute, Gatchina, 188300, St. Petersburg (Russian Federation); Ryskin, M. G. [Petersburg Nuclear Physics Institute, NRC Kurchatov Institute, Gatchina, 188300, St. Petersburg (Russian Federation)

    2016-01-06

    We present a range of physics results for central exclusive production processes at the LHC, using the new SuperChic 2 Monte Carlo event generator. This includes significant theoretical improvements and updates, most importantly a fully differential treatment of the soft survival factor, as well as a greater number of generated processes. We provide an overview of the latest theoretical framework, and consider in detail a selection of final states, namely exclusive 2 and 3 jets, photoproduced vector mesons, two-photon initiated muon and W boson pairs and heavy χ{sub c,b} quarkonia.

  6. 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.

  7. 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.

  8. 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.

  9. 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

  10. Bullying and social exclusion anxiety in schools

    DEFF Research Database (Denmark)

    Søndergaard, Dorte Marie

    2012-01-01

    In this article, I develop a new conceptual framework, a new thinking technology, for understanding the bullying that takes place between children in schools. In addition, I propose a new definition of bullying. This new thinking technology reflects a shift in focus from individual characteristics...... to the social processes that may lead to bullying. The social approach theorises bullying as one of many reactions to particular kinds of social insecurity. The concepts I develop include the necessity of belonging, social exclusion anxiety and the production of contempt and dignity by both children and adults...... during a comprehensive five-year study of bullying....

  11. 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,

  12. Double images encryption method with resistance against the specific attack based on an asymmetric algorithm.

    Science.gov (United States)

    Wang, Xiaogang; Zhao, Daomu

    2012-05-21

    A double-image encryption technique that based on an asymmetric algorithm is proposed. In this method, the encryption process is different from the decryption and the encrypting keys are also different from the decrypting keys. In the nonlinear encryption process, the images are encoded into an amplitude cyphertext, and two phase-only masks (POMs) generated based on phase truncation are kept as keys for decryption. By using the classical double random phase encoding (DRPE) system, the primary images can be collected by an intensity detector that located at the output plane. Three random POMs that applied in the asymmetric encryption can be safely applied as public keys. Simulation results are presented to demonstrate the validity and security of the proposed protocol.

  13. Asymmetric capture of Dirac dark matter by the Sun

    International Nuclear Information System (INIS)

    Current problems with the solar model may be alleviated if a significant amount of dark matter from the galactic halo is captured in the Sun. We discuss the capture process in the case where the dark matter is a Dirac fermion and the background halo consists of equal amounts of dark matter and anti-dark matter. By considering the case where dark matter and anti-dark matter have different cross sections on solar nuclei as well as the case where the capture process is considered to be a Poisson process, we find that a significant asymmetry between the captured dark particles and anti-particles is possible even for an annihilation cross section in the range expected for thermal relic dark matter. Since the captured number of particles are competitive with asymmetric dark matter models in a large range of parameter space, one may expect solar physics to be altered by the capture of Dirac dark matter. It is thus possible that solutions to the solar composition problem may be searched for in these type of models

  14. Probing the perturbative dynamics of exclusive meson pair production

    CERN Document Server

    Harland-Lang, L A; Ryskin, M G; Stirling, W J

    2013-01-01

    We present the results of a recent novel application of the `hard exclusive' perturbative formalism to the process gg --> MMbar at large angles, where M (Mbar) is a light meson (anti-meson). As well as discussing the important theoretical features of the relevant leading-order gg --> qqbar(gg) qqbar(gg) 6-parton amplitudes, we also comment on their phenomenological implications. In particular, we consider the central exclusive production of meson pairs at comparatively large transverse momentum k_t, which is expected to proceed via this mechanism. We show that this leads to various non-trivial predictions for a range of exclusive processes, and that the cross sections for the eta' and eta mesons display significant sensitivity to any valence gg component of the meson wavefunctions.

  15. Probing the perturbative dynamics of exclusive meson pair production

    Science.gov (United States)

    Harland-Lang, L. A.; Khoze, V. A.; Ryskin, M. G.; Stirling, W. J.

    2013-10-01

    We present the results of a recent novel application of the 'hard exclusive' perturbative formalism to the process gg → MMbar at large angles, where M (Mbar) is a light meson (anti-meson). As well as discussing the important theoretical features of the relevant leading-order gg → qqbar (gg) qqbar (gg) 6-parton amplitudes, we also comment on their phenomenological implications. In particular, we consider the central exclusive production of meson pairs at comparatively large transverse momentum k⊥, which is expected to proceed via this mechanism. We show that this leads to various non-trivial predictions for a range of exclusive processes, and that the cross sections for the η‧ and η mesons display significant sensitivity to any valence gg component of the meson wavefunctions.

  16. Problems of Chernobyl exclusion zone

    International Nuclear Information System (INIS)

    The collection reflects the results of researches and test-design activities in the exclusion area of the Chernobyl NPP directed to elaborate the equipment and devices for scientific researches and elimination of the accident after effects at the Chernobyl NPP and to study composition and structure of solid-phase bearers of the activity in the soil of the exclusion area, form transformation of decay products, radionuclide composition of the fuel precipitation in the nearest zone of the Chernobyl NPP. Special attention is paid to medical-biological problems of the accident after effects influence on flora, fauna and human health, labour conditions and sick rate of people working in the exclusion area

  17. Impacts of complex behavioral responses on asymmetric interacting spreading dynamics in multiplex networks

    OpenAIRE

    Quan-Hui Liu; Wei Wang; Ming Tang; Hai-Feng Zhang

    2016-01-01

    Information diffusion and disease spreading in communication-contact layered network are typically asymmetrically coupled with each other, in which how an individual being aware of disease responds to the disease can significantly affect the disease spreading. Many recent studies have demonstrated that human behavioral adoption is a complex and non-Markovian process, where the probability of adopting one behavior is dependent on the cumulative times of the received information and the social ...

  18. Exclusive channels in semi-inclusive production of pions and kaons

    Energy Technology Data Exchange (ETDEWEB)

    Markus Diehl; Wolfgang Kugler; Andreas Schaefer; Christian Weiss

    2005-06-01

    We investigate the role of exclusive channels in semi-inclusive electroproduction of pions and kaons. Using the QCD factorization theorem for hard exclusive processes we evaluate the cross sections for exclusive pseudoscalar and vector meson production in terms of generalized parton distributions and meson distribution amplitudes. We investigate the uncertainties arising from the modeling of the nonperturbative input quantities. Combining these results with available experimental data, we compare the cross sections for exclusive channels to that obtained from quark fragmentation in semi-inclusive deep inelastic scattering. We find that rho0 production is the only exclusive channel with significant contributions to semi-inclusive pion production at large z and moderate Q2. The corresponding contribution to kaon production from the decay of exclusively produced phi and Kstar is rather small.

  19. Social exclusion modulates priorities of attention allocation in cognitive control.

    Science.gov (United States)

    Xu, Mengsi; Li, Zhiai; Diao, Liuting; Zhang, Lijie; Yuan, Jiajin; Ding, Cody; Yang, Dong

    2016-01-01

    Many studies have investigated how exclusion affects cognitive control and have reported inconsistent results. However, these studies usually treated cognitive control as a unitary concept, whereas it actually involved two main sub-processes: conflict detection and response implementation. Furthermore, existing studies have focused primarily on exclusion's effects on conscious cognitive control, while recent studies have shown the existence of unconscious cognitive control. Therefore, the present study investigated whether and how exclusion affects the sub-processes underlying conscious and unconscious cognitive control differently. The Cyberball game was used to manipulate social exclusion and participants subsequently performed a masked Go/No-Go task during which event-related potentials were measured. For conscious cognitive control, excluded participants showed a larger N2 but smaller P3 effects than included participants, suggesting that excluded people invest more attention in conscious conflict detection, but less in conscious inhibition of impulsive responses. However, for unconscious cognitive control, excluded participants showed a smaller N2 but larger P3 effects than included participants, suggesting that excluded people invest less attention in unconscious conflict detection, but more in unconscious inhibition of impulsive responses. Together, these results suggest that exclusion causes people to rebalance attention allocation priorities for cognitive control according to a more flexible and adaptive strategy. PMID:27511746

  20. Problems of Chernobyl exclusion zone

    International Nuclear Information System (INIS)

    The collection comprises the results of researches and design activity in the ChNPP exclusion zone with the aim to develop technology, equipment and instruments for RAW management and accident clean-up, studying of the composition and structure of the activity solid bearers in the soil of the exclusion zone and transformation of the radionuclides in the nearest zone of ChNPP. Much attention is paid to medical and biological problems of the accident influence on the flora, fauna and people's health labour conditions and incidence of the people involved

  1. Problems of Chornobyl Exclusion Zone

    International Nuclear Information System (INIS)

    The collection comprises the results of researches and design activity in the ChNPP exclusion zone with the aim to develop technology, equipment and instruments for RAW management and accident clean-up, studying of the composition and structure of the activity solid bearers in the soil of the exclusion zone and transformation of the radionuclides in the nearest zone of ChNPP. Much attention is paid to medical and biological problems of the accident influence on the flora, fauna and people's health, labour conditions and incidence of the people involved.

  2. Interfacial properties of asymmetrically functionalized citrate-stabilized gold and silver nanoparticles related to molecular adsorption

    Science.gov (United States)

    Park, Jong-Won

    exclusive placement of Raman probe molecules (4-nitrobenzenethiol) at junctions (hot-spots) of AuNP dimers was achieved through an asymmetric functionalization approach. The orientation of asymmetric nanoparticles in dimers and the location of Raman probes were investigated using surface-enhanced Raman scattering (SERS). A linear correlation of SERS signal with hot-spot population and a SERS enhancement factor are presented. Lastly, AuNPs and AgNPs of small sizes (electron microscopy analyses.

  3. Search for the Exclusive Radiative Decays B -> rho gamma and B -> omega gamma

    CERN Document Server

    Aubert, Bernard; Gaillard, Jean-Marc; Hicheur, A; Karyotakis, Yu; Lees, J P; Robbe, P; Tisserand, V; Zghiche, A; Palano, A; Pompili, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Borgland, A W; Breon, A B; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Gill, M S; Gritsan, A V; Groysman, Y; Jacobsen, R G; Kadel, R W; Kadyk, J; Kerth, L T; Kolomensky, Yu G; Kral, J F; Le Clerc, C; Levi, M E; Lynch, G; Mir, L M; Oddone, P J; Orimoto, T J; Pripstein, M; Roe, N A; Romosan, A; Ronan, Michael T; Shelkov, V G; Telnov, A V; Wenzel, W A; Harrison, T J; Hawkes, C M; Knowles, D J; O'Neale, S W; Penny, R C; Watson, A T; Watson, N K; Deppermann, T; Goetzen, K; Koch, H; Lewandowski, B; Peters, K; Schmücker, H; Steinke, M; Barlow, N R; Bhimji, W; Boyd, J T; Chevalier, N; Clark, P J; Cottingham, W N; MacKay, C; Wilson, F F; Abe, K; Hearty, C; Mattison, T S; McKenna, J A; Thiessen, D; Jolly, S; McKemey, A K; Blinov, V E; Bukin, A D; Buzykaev, A R; Golubev, V B; Ivanchenko, V N; Korol, A A; Kravchenko, E A; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Yushkov, A N; Best, D; Chao, M; Kirkby, D; Lankford, A J; Mandelkern, M A; McMahon, S; Stoker, D P; Buchanan, C; Chun, S; Hadavand, H K; Hill, E J; MacFarlane, D B; Paar, H P; Prell, S; Rahatlou, S; Raven, G; Schwanke, U; Sharma, V; Berryhill, J W; Campagnari, C; Dahmes, B; Hart, P A; Kuznetsova, N P; Levy, S L; Long, O; Lu, A; Mazur, M A; Richman, J D; Verkerke, W; Beringer, J; Eisner, A M; Grothe, M; Heusch, C A; Lockman, W S; Pulliam, T; Schalk, T L; Schmitz, R E; Schumm, B A; Seiden, A; Turri, M; Walkowiak, W; Williams, D C; Wilson, M G; Chen, E; Dubois-Felsmann, G P; Dvoretskii, A; Hitlin, D G; Porter, F C; Ryd, A; Samuel, A; Yang, S; Jayatilleke, S M; Mancinelli, G; Meadows, B T; Sokoloff, M D; Barillari, T; Bloom, P; Ford, W T; Nauenberg, U; Olivas, A; Rankin, P; Roy, J; Smith, J G; Van Hoek, W C; Zhang, L; Harton, J L; Hu, T; Krishnamurthy, M; Soffer, A; Toki, W H; Wilson, R J; Zhang, J; Altenburg, D; Brandt, T; Brose, J; Colberg, T; Dickopp, M; Dubitzky, R S; Hauke, A; Maly, E; Müller-Pfefferkorn, R; Otto, S; Schubert, Klaus R; Schwierz, R; Spaan, B; Wilden, L; Bernard, D; Bonneaud, G R; Brochard, F; Cohen-Tanugi, J; Ferrag, S; T'Jampens, S; Thiebaux, C; Vasileiadis, G; Verderi, M; Anjomshoaa, A; Bernet, R; Khan, A; Lavin, D; Muheim, F; Playfer, S; Swain, J E; Tinslay, J; Falbo, M; Borean, C; Bozzi, C; Piemontese, L; Sarti, A; Treadwell, E; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; De Sangro, R; Falciai, D; Finocchiaro, G; Patteri, P; Peruzzi, I M; Piccolo, M; Zallo, A; Bagnasco, S; Buzzo, A; Contri, R; Crosetti, G; Lo Vetere, M; Macri, M; Monge, M R; Passaggio, S; Pastore, F C; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Bailey, S; Morii, M; Bartoldus, R; Grenier, G J; Mallik, U; Cochran, J; Crawley, H B; Lamsa, J; Meyer, W T; Rosenberg, E I; Yi, J; Davier, M; Grosdidier, G; Höcker, A; Lacker, H M; Laplace, S; Le Diberder, F R; Lepeltier, V; Lutz, A M; Petersen, T C; Plaszczynski, S; Schune, M H; Tantot, L; Trincaz-Duvoid, S; Wormser, G; Bionta, R M; Brigljevic, V; Lange, D J; Van Bibber, K; Wright, D M; Bevan, A J; Fry, J R; Gabathuler, Erwin; Gamet, R; George, M; Kay, M; Payne, D J; Sloane, R J; Touramanis, C; Aspinwall, M L; Bowerman, D A; Dauncey, P D; Egede, U; Eschrich, I; Morton, G W; Nash, J A; Sanders, P; Smith, D; Taylor, G P; Back, J J; Bellodi, G; Dixon, P; Harrison, P F; Potter, R J L; Shorthouse, H W; Strother, P; Vidal, P B; Cowan, G; Flächer, H U; George, S; Green, M G; Kurup, A; Marker, C E; McMahon, T R; Ricciardi, S; Salvatore, F; Vaitsas, G; Winter, M A; Brown, D; Davis, C L; Allison, J; Barlow, R J; Forti, A C; Jackson, F; Lafferty, G D; Lyon, A J; Savvas, N; Weatherall, J H; Williams, J C; Farbin, A; Jawahery, A; Lillard, V; Roberts, D A; Schieck, J; Blaylock, G; Dallapiccola, C; Flood, K T; Hertzbach, S S; Kofler, R; Koptchev, V B; Moore, T B; Stängle, H; Willocq, S; Brau, B; Cowan, R; Sciolla, G; Taylor, F; Yamamoto, R K; Milek, M; Patel, P M; Palombo, F; Bauer, J M; Cremaldi, L M; Eschenburg, V; Kroeger, R; Reidy, J; Sanders, D A; Summers, D J; Hast, C; Taras, P; Rene, J A; Nicholson, H; Cartaro, C; Cavallo, N; De Nardo, Gallieno; Fabozzi, F; Gatto, C; Lista, L; Paolucci, P; Piccolo, D; Sciacca, C; LoSecco, J M; Alsmiller, J R G; Gabriel, T A; Brau, J E; Frey, R; Iwasaki, M; Potter, C T; Sinev, N B; Strom, D; Torrence, E; Colecchia, F; Dorigo, A; Galeazzi, F; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Benayoun, M; Briand, H; Chauveau, J; David, P; La Vaissière, C de; Del Buono, L; Hamon, O; Leruste, P; Ocariz, J; Pivk, M; Roos, L; Stark, J; Manfredi, P F; Re, V; Speziali, V; Gladney, L; Guo, Q H; Panetta, J; Angelini, C; Batignani, G; Bettarini, S; Bondioli, M; Bucci, F; Calderini, G; Campagna, E

    2002-01-01

    A search for the exclusive radiative decays B->rho(770) gamma and B^0->omega(782) gamma is performed on a sample of 84 million BB-bar events collected by the BABAR detector at the PEP-II asymmetric e^+e^- collider. No significant signal is seen in any of the channels. We set preliminary upper limits of BR[B^0->rho^0 gamma] rho^+ gamma] omega gamma] rho gamma, we find the preliminary limit BR[B -> rho gamma] rho gamma]/BR[B-> K* gamma] < 0.047 at 90% Confidence Level.

  4. Asymmetric bias in user guided segmentations of brain structures.

    Science.gov (United States)

    Maltbie, Eric; Bhatt, Kshamta; Paniagua, Beatriz; Smith, Rachel G; Graves, Michael M; Mosconi, Matthew W; Peterson, Sarah; White, Scott; Blocher, Joseph; El-Sayed, Mohammed; Hazlett, Heather C; Styner, Martin A

    2012-01-16

    Brain morphometric studies often incorporate comparative hemispheric asymmetry analyses of segmented brain structures. In this work, we present evidence that common user guided structural segmentation techniques exhibit strong left-right asymmetric biases and thus fundamentally influence any left-right asymmetry analyses. In this study, MRI scans from ten pediatric subjects were employed for studying segmentations of amygdala, globus pallidus, putamen, caudate, and lateral ventricle. Additionally, two pediatric and three adult scans were used for studying hippocampus segmentation. Segmentations of the sub-cortical structures were performed by skilled raters using standard manual and semi-automated methods. The left-right mirrored versions of each image were included in the data and segmented in a random order to assess potential left-right asymmetric bias. Using shape analysis we further assessed whether the asymmetric bias is consistent across subjects and raters with the focus on the hippocampus. The user guided segmentation techniques on the sub-cortical structures exhibited left-right asymmetric volume bias with the hippocampus displaying the most significant asymmetry values (porigin of this asymmetric bias is considered to be based in laterality of visual perception; therefore segmentations with any degree of user interaction contain an asymmetric bias. The aim of our study is to raise awareness in the neuroimaging community regarding the presence of the asymmetric bias and its influence on any left-right hemispheric analyses. We also recommend reexamining previous research results in the light of this new finding. PMID:21889995

  5. High-Voltage, Asymmetric-Waveform Generator

    Science.gov (United States)

    Beegle, Luther W.; Duong, Tuan A.; Duong, Vu A.; Kanik, Isik

    2008-01-01

    The shapes of waveforms generated by commercially available analytical separation devices, such as some types of mass spectrometers and differential mobility spectrometers are, in general, inadequate and result in resolution degradation in output spectra. A waveform generator was designed that would be able to circumvent these shortcomings. It is capable of generating an asymmetric waveform, having a peak amplitude as large as 2 kV and frequency of several megahertz, which can be applied to a capacitive load. In the original intended application, the capacitive load would consist of the drift plates in a differential-mobility spectrometer. The main advantage to be gained by developing the proposed generator is that the shape of the waveform is made nearly optimum for various analytical devices requiring asymmetric-waveform such as differential-mobility spectrometers. In addition, this waveform generator could easily be adjusted to modify the waveform in accordance with changed operational requirements for differential-mobility spectrometers. The capacitive nature of the load is an important consideration in the design of the proposed waveform generator. For example, the design provision for shaping the output waveform is based partly on the principle that (1) the potential (V) on a capacitor is given by V=q/C, where C is the capacitance and q is the charge stored in the capacitor; and, hence (2) the rate of increase or decrease of the potential is similarly proportional to the charging or discharging current. The proposed waveform generator would comprise four functional blocks: a sine-wave generator, a buffer, a voltage shifter, and a high-voltage switch (see Figure 1). The sine-wave generator would include a pair of operational amplifiers in a feedback configuration, the parameters of which would be chosen to obtain a sinusoidal timing signal of the desired frequency. The buffer would introduce a slight delay (approximately equal to 20 ns) but would otherwise

  6. Can the electricity market be characterised by asymmetric behaviour?

    International Nuclear Information System (INIS)

    In this paper, we test for asymmetric behaviour of industrial and residential electricity demand for the G7 countries, using the entropy-based test for symmetry suggested by [Racine, J., and Maasoumi, E., 2007. A versatile and robust metric entropy test of time-reversibility, and other hypotheses. Journal of Econometrics 138(2), 547-567; Racine, J., and Maasoumi, E., 2008. A robust entropy-based test of asymmetry for discrete and continuous processes. Econometric Reviews 28, 246-261], the Triples test of [Randles, R., Flinger, M., Policello, G., and Wolfe, D., 1980. An asymptotically distribution-free test for symmetry versus asymmetry. Journal of the American Statistical Association 75, 168-172] and the [Bai, J., and Ng, S., 2001. A consistent test for conditional symmetry in time series models. Journal of Econometrics 103, 225-258] test for conditional symmetry. Using data that spans over three decades, we find overwhelming evidence of conditional symmetry of residential and industrial electricity consumption. This finding implies that the use of econometric tests based on linear data generating processes is credible. (author)

  7. Can the electricity market be characterised by asymmetric behaviour?

    International Nuclear Information System (INIS)

    In this paper, we test for asymmetric behaviour of industrial and residential electricity demand for the G7 countries, using the entropy-based test for symmetry suggested by [Racine, J., and Maasoumi, E., 2007. A versatile and robust metric entropy test of time-reversibility, and other hypotheses. Journal of Econometrics 138(2), 547-567; Racine, J., and Maasoumi, E., 2008. A robust entropy-based test of asymmetry for discrete and continuous processes. Econometric Reviews 28, 246-261], the Triples test of [Randles, R., Flinger, M., Policello, G., and Wolfe, D., 1980. An asymptotically distribution-free test for symmetry versus asymmetry. Journal of the American Statistical Association 75, 168-172] and the [Bai, J., and Ng, S., 2001. A consistent test for conditional symmetry in time series models. Journal of Econometrics 103, 225-258] test for conditional symmetry. Using data that spans over three decades, we find overwhelming evidence of conditional symmetry of residential and industrial electricity consumption. This finding implies that the use of econometric tests based on linear data generating processes is credible.

  8. Critical Differences of Asymmetric Magnetic Reconnection from Standard Models

    Science.gov (United States)

    Nitta, S.; Wada, T.; Fuchida, T.; Kondoh, K.

    2016-09-01

    We have clarified the structure of asymmetric magnetic reconnection in detail as the result of the spontaneous evolutionary process. The asymmetry is imposed as ratio k of the magnetic field strength in both sides of the initial current sheet (CS) in the isothermal equilibrium. The MHD simulation is carried out by the HLLD code for the long-term temporal evolution with very high spatial resolution. The resultant structure is drastically different from the symmetric case (e.g., the Petschek model) even for slight asymmetry k = 2. (1) The velocity distribution in the reconnection jet clearly shows a two-layered structure, i.e., the high-speed sub-layer in which the flow is almost field aligned and the acceleration sub-layer. (2) Higher beta side (HBS) plasma is caught in a lower beta side plasmoid. This suggests a new plasma mixing process in the reconnection events. (3) A new large strong fast shock in front of the plasmoid forms in the HBS. This can be a new particle acceleration site in the reconnection system. These critical properties that have not been reported in previous works suggest that we contribute to a better and more detailed knowledge of the reconnection of the standard model for the symmetric magnetic reconnection system.

  9. Morphological study of the asymmetrical buccal cavity of the flatfish common solea (Solea solea) and its relation to the type of feeding

    OpenAIRE

    Neveen El Said Reda El Bakary

    2014-01-01

    Objective: To investigate the surface architecture of the asymmetrical buccal cavity of Solea solea which are considered one of the most important predators in benthic communities. Methods: Adult Solea solea were obtained from Mediterranean Sea near Damietta. The heads were removed and processed for scanning electron microscopy. Its buccal cavity is asymmetrical and divided into roof and floor and the tongue for histological studies. Results: The buccal cavity roof is formed from upper ...

  10. Simulation of Chaos in Asymmetric Nonlinear Chua's Circuit

    Institute of Scientific and Technical Information of China (English)

    WANG Yu-fei; QIAO Shu-tong; JIANG Jian-guo

    2008-01-01

    In order to describe practical chaotic systems exactly, we presented a simple modified Chua's circuit,which contains an asymmetric nonlinear resistive element. Mathematical analysis was made, and simulation study was performed by MATLAB. By varying the value of linear resistor in the circuit, rich variety dynamical behaviors were observed, such as DC equilibrium point, Hopf bifurcation, period-doubling bifurcation,single-scroll strange attractor, periodic windows, and asymmetric double-scroll strange attractor. The extreme sensitivity in the state trajectory with respect to the initial conditions was exhibited; the special characteristic of asymmetric nonlinear Chua's circuit was found also.

  11. The Dualism of Asymmetric Information in Agricultural Insurance

    Directory of Open Access Journals (Sweden)

    Xuemei Yang

    2013-07-01

    Full Text Available Asymmetric information objectively exists in the insurance market, especially in agricultural insurance, which has a great impact on the insurance contract and market operation. This paper designs two game models to analyse the dualism of asymmetric information in agricultural insurance and its reasons of forming. We find that, the particularity of agricultural production, the agricultural risk diversification and the benefits’ spillover of the agricultural insurance are the main causes of asymmetric information. Therefore, this paper puts forward that establishment of appropriate agricultural insurance mode, optimization of insurance policy design and increasing investment in science and technology, increasing farmers’ insurance consciousness and establishing supervision system

  12. Generic approach for synthesizing asymmetric nanoparticles and nanoassemblies

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Yugang; Hu, Yongxing

    2015-05-26

    A generic route for synthesis of asymmetric nanostructures. This approach utilizes submicron magnetic particles (Fe.sub.3O.sub.4--SiO.sub.2) as recyclable solid substrates for the assembly of asymmetric nanostructures and purification of the final product. Importantly, an additional SiO.sub.2 layer is employed as a mediation layer to allow for selective modification of target nanoparticles. The partially patched nanoparticles are used as building blocks for different kinds of complex asymmetric nanostructures that cannot be fabricated by conventional approaches. The potential applications such as ultra-sensitive substrates for surface enhanced Raman scattering (SERS) have been included.

  13. Azimuthal asymmetries in hard exclusive meson muoproduction off transversely polarized protons

    Energy Technology Data Exchange (ETDEWEB)

    Wolbeek, Johannes ter

    2015-04-15

    In 2010, the COMPASS experiment at CERN took data with a 160 GeV μ{sup +} beam and a transversely polarized NH{sub 3} target. In this thesis, this data is analyzed for azimuthal target spin asymmetries, including five single spin and three double spin asymmetries in hard exclusive ω meson production. This thesis is the worldwide first analysis investigating on azimuthal asymmetries in exclusive ω muoproduction (μ'p→μ'+p'+ω→μ'+p'+π{sup +}π{sup -}π{sup 0}). The analysis is confronted with several challenges beside the small cross section of the examined process. The detection of two photons in the final state requires an excellent performance of the electromagnetic calorimeters as well as a good understanding of the detector. To increase the yield of reconstructed γ pairs from a decaying π{sup 0} meson, a decay product of the ω meson, extensive studies relating to performance of the calorimeters were necessary. Firstly the time information of the calorimeters had to be parametrized in dependence of the cluster energy to ensure the assignment of beam particle and photon due to a correlation in time. Secondly, a parametrization of the invariant mass of the photon pair was performed in terms of the energy of the reconstructed π{sup 0}, for the better discrimination of signal and background. In the setup with the transversely polarized target, the recoiled proton cannot be detected. Thus in order to ensure the exclusivity of the process, the missing energy is calculated. The signal region, defined at vertical stroke E{sub miss} vertical stroke < 3GeV, contains ω mesons from exclusive events as well as from semi-inclusive production. Hence the understanding of non-exclusive background is essential for the further analysis. For this purpose, a semiinclusive Monte Carlo sample is studied. In order to reach a better agreement of the Monte Carlo and data, like-sign samples from both, real data and Monte Carlo, are compared and the

  14. 非对称弯曲微流道中粒子惯性聚焦动态过程及流速调控机理研究%Dynamic process and flow-rate regulation mechanism of particle inertial focusing in an asymmetric ally curved microchannel

    Institute of Scientific and Technical Information of China (English)

    唐文来; 项楠; 张鑫杰; 黄笛; 倪中华

    2015-01-01

    In this paper, an asymmetrically curved microchannel device is designed and fabricated to quantitatively characterize the dynamic inertial focusing process of polystyrene particles and blood cells flowing along the channel. The experimental investigations are systematically carried out to probe into the regulation mechanisms of flow rate and particle size. Specifically, based on the particle fluorescent streak images and the corresponding intensity profiles at specific downstream positions, the lateral migration behaviors of particles in the mirochannel can be divided into two stages: the formation of focused streak and the shift of focusing position. It is also found that the channel structures with small radii are dominant during the whole inertial focusing process. A three-stage model is then presented to elucidate the flow-rate regulation mechanism in terms of the competition between inertial lift force and Dean drag force, according to the evolution of particle focusing dynamics with increasing flow rates. By making comparisons of focusing position and focusing ratio between two different-sized particles under various experimental conditions, we find that the larger particles have better focusing performances and stabilities, and the relative focusing position of different-sized particles can be adjusted by changing the driving flow rate. Finally, the applicability of the explored inertial focusing mechanisms for manipulating biological particles with complex features is investigated by analyzing the lateral migration behaviors of blood cells in the asymmetrically curved microchannel. The obtained conclusions are very important for understanding the particle focusing dynamics in micro-scale flows and developing the point-of-care diagnostic instruments.%设计制作了一种具有非对称弯曲微流道结构的微流控芯片,搭建实验平台定量表征聚苯乙烯粒子和血细胞沿流道的动态惯性聚焦过程, 并系统研究了流体流速和粒

  15. Examining the Cultural Leadership Behaviors of Schoo l Principal s within the Context of Symmetric and Asymmetric School Culture

    Directory of Open Access Journals (Sweden)

    Betül BALKAR

    2015-08-01

    Full Text Available The aim of this study is to determine the opinions of teachers on contributions of school principals’ cultural leadership behaviors to forming symmetric and asymmetric culture. The participants of the study consisted of 27 secondary school teachers working in Gaziantep province. Data of the study were collected through semi - structured interviews and analyzed through content analysis. Contributions of each cultural leader ship behavior to symmetric and asymmetric culture types were determined by taking relations between cultural leadership behaviors and symmetric and asymmetric cultures into consideration in the process of content analysis. According to the findings of the study ; supporting development of teachers and reflecting developments and innovations on schools are among the cultural leadership behaviors contributing to forming asymmetric culture at schools. Interpreting tasks and missions of school and ensuring neces sary environment for keeping social values alive at schools are among the cultural leadership behaviors contributing to forming symmetric culture at schools. Based on the results of the study, it is suggested that school principals should follow developmen ts in educational issues and transfer these developments into school practices. They should place more importance on supporting innovative behaviors of teachers in order to create asymmetric culture at schools.

  16. Dynamics of asymmetrical hybridization in North American wood ferns: reconciling patterns of inheritance with gametophyte reproductive biology.

    Science.gov (United States)

    Testo, Weston L; Watkins, James E; Barrington, David S

    2015-04-01

    Hybridization is an important evolutionary force in plants, but the mechanisms underlying it have not been well studied for many groups. In particular, the drivers of non-random patterns of interspecific gene flow (asymmetrical hybridization) remain poorly understood, especially in the seed-free vascular plants. Here, we examine patterns of asymmetrical hybridization in two widespread fern hybrids from eastern North America and study the role of gametophyte ecology in the determination of hybridization bias. We characterized the maternal parentage of > 140 hybrid sporophytes by sequencing a c. 350-bp region of chloroplast DNA (cpDNA). To identify factors contributing to patterns of asymmetrical hybridization, we cultured gametophytes of the parental species and evaluated critical aspects of their reproductive biology. We found that asymmetrical hybridization was prevalent across the populations of both hybrids. Reproductive traits varied across species and suggest that selfing potential, antheridiogen responsiveness, sperm dispersal capacity and gamete size all contribute to the mediation of the direction of hybridization in this group. Our findings suggest that asymmetrical hybridization in ferns is driven by an array of reproductive traits. This study helps to sharpen and define a mechanistic understanding of patterns of hybridization in this group and demonstrates the importance of considering gametophyte biology when studying evolutionary processes in ferns.

  17. Exclusive meson production at NLO

    Energy Technology Data Exchange (ETDEWEB)

    Diehl, M.; Kugler, W.

    2007-06-15

    We report on numerical studies of the NLO corrections to exclusive meson electroproduction, both in collider and fixed-target kinematics. Corrections are found to be huge at small x{sub B} and moderate at intermediate or large x{sub B}. (orig.)

  18. Exclusive Decays of Beauty Hadrons

    OpenAIRE

    Sachrajda, C. T.

    1996-01-01

    The principal difficulty in deducing weak interaction properties from experimental measurements of $B$-decays lies in controlling the strong interaction effects. In this talk I review the status of theoretical calculations of the amplitudes for exclusive leptonic and semileptonic decays, in the latter case with special emphasis on the extraction of the $V_{cb}$ and $V_{ub}$ matrix elements.

  19. Exclusive meson production at COMPASS

    CERN Document Server

    Pochodzalla, J; Moinester, M A; Piller, G; Sandacz, A; Vanderhaeghen, M; Pochodzalla, Josef; Mankiewicz, Lech; Moinester, Murray; Piller, Gunther; Sandacz, Andrzej; Vanderhaeghen, Marc

    1999-01-01

    We explore the feasibility to study exclusive meson production (EMP) in hard muon-proton scattering at the COMPASS experiment. These measurements constrain the off-forward parton distributions (OFPD's) of the proton, which are related to the quark orbital contribution to the proton spin.

  20. Observation of Central Exclusive Diphoton Production at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Brucken, Jens Erik [Univ. of Helsinki (Finland); Helsinki Inst. of Physics (Finland)

    2013-01-01

    We have observed exclusive γγ production in proton-antiproton collisions at the Tevatron at √ s = 1.96 TeV. We use data corresponding to 1.11 ± 0.07 fb-1 integrated luminosity taken by the Run II Collider Detector at Fermilab, with a trigger requiring two electromagnetic showers, each with transverse energy ET > 2 GeV, and vetoing on hits in the forward beam shower counters. We select events with two electromagnetic showers, each with transverse energy ET > 2.5 GeV and pseudorapidity |η| < 1.0, with no other particles detected in -7.4 < η < +7.4. The two showers have similar ET and an azimuthal angle separation Δφ ~ π; we find 34 events with exactly two matching charged particle tracks, agreeing with expectations for the QED process p¯p → p+e+e- + ¯p by two photon exchange; and we find 43 events with no tracks. The latter are candidates for the exclusive process p¯p → p + γγ + ¯p by double pomeron exchange. We use the strip and wire chambers at the longitudinal shower maximum position within the calorimeter to measure a possible exclusive background from IP + IP → π0π0, and conclude that it is consistent with zero and is < 15 events at 95% C.L. The measured cross section is σγγ,excl(|η| < 1, ET (γ) > 2.5 GeV) = 2.48 +0.40 -0.35(stat) +0.40 -0.51(syst) pb and in agreement with the theoretical predictions. This process is closely related to exclusive Higgs boson production pp → p + H + p at the Large Hadron Collider. The observation of the exclusive production of diphotons shows that exclusive Higgs production can happen and could be observed with a proper experimental setup.