The canonical and grand canonical models for nuclear ...
Indian Academy of Sciences (India)
Many observables seen in intermediate energy heavy-ion collisions can be explained on the basis of statistical equilibrium. Calculations based on statistical equilibrium can be implemented in microcanonical ensemble, canonical ensemble or grand canonical ensemble. This paper deals with calculations with canonical ...
Grand Canonical Ensembles in General Relativity
International Nuclear Information System (INIS)
Klein, David; Yang, Wei-Shih
2012-01-01
We develop a formalism for general relativistic, grand canonical ensembles in space-times with timelike Killing fields. Using that, we derive ideal gas laws, and show how they depend on the geometry of the particular space-times. A systematic method for calculating Newtonian limits is given for a class of these space-times, which is illustrated for Kerr space-time. In addition, we prove uniqueness of the infinite volume Gibbs measure, and absence of phase transitions for a class of interaction potentials in anti-de Sitter space.
A grand-canonical ensemble of randomly triangulated surfaces
International Nuclear Information System (INIS)
Jurkiewicz, J.; Krzywicki, A.; Petersson, B.
1986-01-01
An algorithm is presented generating the grand-canonical ensemble of discrete, randomly triangulated Polyakov surfaces. The algorithm is used to calculate the susceptibility exponent, which controls the existence of the continuum limit of the considered model, for the dimensionality of the embedding space ranging from 0 to 20. (orig.)
Bitcoin Market Volatility Analysis Using Grand Canonical Minority Game
Directory of Open Access Journals (Sweden)
Matteo Ortisi
2016-12-01
Full Text Available In this paper we propose to use the Grand Canonical Minority Game (GCMG, a highly simplified financial market model as a model of bitcoin market to show how the lack of an income for “miners”, similar to yield earned by bond holders, could be a structural reason for high volatility of bitcoin price in a reference currency. Coherently with present analysis, the introduction of future contracts on bitcoin would have the effect of reducing the overall market volatility.
Symmetric minimally entangled typical thermal states for canonical and grand-canonical ensembles
Binder, Moritz; Barthel, Thomas
2017-05-01
Based on the density matrix renormalization group (DMRG), strongly correlated quantum many-body systems at finite temperatures can be simulated by sampling over a certain class of pure matrix product states (MPS) called minimally entangled typical thermal states (METTS). When a system features symmetries, these can be utilized to substantially reduce MPS computation costs. It is conceptually straightforward to simulate canonical ensembles using symmetric METTS. In practice, it is important to alternate between different symmetric collapse bases to decrease autocorrelations in the Markov chain of METTS. To this purpose, we introduce symmetric Fourier and Haar-random block bases that are efficiently mixing. We also show how grand-canonical ensembles can be simulated efficiently with symmetric METTS. We demonstrate these approaches for spin-1 /2 X X Z chains and discuss how the choice of the collapse bases influences autocorrelations as well as the distribution of measurement values and, hence, convergence speeds.
Multivariable extrapolation of grand canonical free energy landscapes
Mahynski, Nathan A.; Errington, Jeffrey R.; Shen, Vincent K.
2017-12-01
We derive an approach for extrapolating the free energy landscape of multicomponent systems in the grand canonical ensemble, obtained from flat-histogram Monte Carlo simulations, from one set of temperature and chemical potentials to another. This is accomplished by expanding the landscape in a Taylor series at each value of the order parameter which defines its macrostate phase space. The coefficients in each Taylor polynomial are known exactly from fluctuation formulas, which may be computed by measuring the appropriate moments of extensive variables that fluctuate in this ensemble. Here we derive the expressions necessary to define these coefficients up to arbitrary order. In principle, this enables a single flat-histogram simulation to provide complete thermodynamic information over a broad range of temperatures and chemical potentials. Using this, we also show how to combine a small number of simulations, each performed at different conditions, in a thermodynamically consistent fashion to accurately compute properties at arbitrary temperatures and chemical potentials. This method may significantly increase the computational efficiency of biased grand canonical Monte Carlo simulations, especially for multicomponent mixtures. Although approximate, this approach is amenable to high-throughput and data-intensive investigations where it is preferable to have a large quantity of reasonably accurate simulation data, rather than a smaller amount with a higher accuracy.
International Nuclear Information System (INIS)
Schoen, M.
1995-01-01
In this article the Taylor-expansion method is introduced by which Monte Carlo (MC) simulations in the canonical ensemble can be speeded up significantly, Substantial gains in computational speed of 20-40% over conventional implementations of the MC technique are obtained over a wide range of densities in homogeneous bulk phases. The basic philosophy behind the Taylor-expansion method is a division of the neighborhood of each atom (or molecule) into three different spatial zones. Interactions between atoms belonging to each zone are treated at different levels of computational sophistication. For example, only interactions between atoms belonging to the primary zone immediately surrounding an atom are treated explicitly before and after displacement. The change in the configurational energy contribution from secondary-zone interactions is obtained from the first-order term of a Taylor expansion of the configurational energy in terms of the displacement vector d. Interactions with atoms in the tertiary zone adjacent to the secondary zone are neglected throughout. The Taylor-expansion method is not restricted to the canonical ensemble but may be employed to enhance computational efficiency of MC simulations in other ensembles as well. This is demonstrated for grand canonical ensemble MC simulations of an inhomogeneous fluid which can be performed essentially on a modern personal computer
Grand canonical validation of the bipartite international trade network
Straka, Mika J.; Caldarelli, Guido; Saracco, Fabio
2017-08-01
Devising strategies for economic development in a globally competitive landscape requires a solid and unbiased understanding of countries' technological advancements and similarities among export products. Both can be addressed through the bipartite representation of the International Trade Network. In this paper, we apply the recently proposed grand canonical projection algorithm to uncover country and product communities. Contrary to past endeavors, our methodology, based on information theory, creates monopartite projections in an unbiased and analytically tractable way. Single links between countries or products represent statistically significant signals, which are not accounted for by null models such as the bipartite configuration model. We find stable country communities reflecting the socioeconomic distinction in developed, newly industrialized, and developing countries. Furthermore, we observe product clusters based on the aforementioned country groups. Our analysis reveals the existence of a complicated structure in the bipartite International Trade Network: apart from the diversification of export baskets from the most basic to the most exclusive products, we observe a statistically significant signal of an export specialization mechanism towards more sophisticated products.
Grand canonical validation of the bipartite international trade network.
Straka, Mika J; Caldarelli, Guido; Saracco, Fabio
2017-08-01
Devising strategies for economic development in a globally competitive landscape requires a solid and unbiased understanding of countries' technological advancements and similarities among export products. Both can be addressed through the bipartite representation of the International Trade Network. In this paper, we apply the recently proposed grand canonical projection algorithm to uncover country and product communities. Contrary to past endeavors, our methodology, based on information theory, creates monopartite projections in an unbiased and analytically tractable way. Single links between countries or products represent statistically significant signals, which are not accounted for by null models such as the bipartite configuration model. We find stable country communities reflecting the socioeconomic distinction in developed, newly industrialized, and developing countries. Furthermore, we observe product clusters based on the aforementioned country groups. Our analysis reveals the existence of a complicated structure in the bipartite International Trade Network: apart from the diversification of export baskets from the most basic to the most exclusive products, we observe a statistically significant signal of an export specialization mechanism towards more sophisticated products.
Improved grand canonical sampling of vapour-liquid transitions.
Wilding, Nigel B
2016-10-19
Simulation within the grand canonical ensemble is the method of choice for accurate studies of first order vapour-liquid phase transitions in model fluids. Such simulations typically employ sampling that is biased with respect to the overall number density in order to overcome the free energy barrier associated with mixed phase states. However, at low temperature and for large system size, this approach suffers a drastic slowing down in sampling efficiency. The culprits are geometrically induced transitions (stemming from the periodic boundary conditions) which involve changes in droplet shape from sphere to cylinder and cylinder to slab. Since the overall number density does not discriminate sufficiently between these shapes, it fails as an order parameter for biasing through the transitions. Here we report two approaches to ameliorating these difficulties. The first introduces a droplet shape based order parameter that generates a transition path from vapour to slab states for which spherical and cylindrical droplets are suppressed. The second simply biases with respect to the number density in a tetragonal subvolume of the system. Compared to the standard approach, both methods offer improved sampling, allowing estimates of coexistence parameters and vapor-liquid surface tension for larger system sizes and lower temperatures.
Method of collective variables with reference system for the grand canonical ensemble
International Nuclear Information System (INIS)
Yukhnovskii, I.R.
1989-01-01
A method of collective variables with special reference system for the grand canonical ensemble is presented. An explicit form is obtained for the basis sixth-degree measure density needed to describe the liquid-gas phase transition. Here the author presents the fundamentals of the method, which are as follows: (1) the functional form for the partition function in the grand canonical ensemble; (2) derivation of thermodynamic relations for the coefficients of the Jacobian; (3) transition to the problem on an adequate lattice; and (4) obtaining of the explicit form for the functional of the partition function
Generation of triangulated random surfaces by the Monte Carlo method in the grand canonical ensemble
International Nuclear Information System (INIS)
Zmushko, V.V.; Migdal, A.A.
1987-01-01
A model of triangulated random surfaces which is the discrete analog of the Polyakov string is considered. An algorithm is proposed which enables one to study the model by the Monte Carlo method in the grand canonical ensemble. Preliminary results on the determination of the critical index γ are presented
A Cannibalistic Approach to Grand Canonical Crystal Growth.
Karmakar, Tarak; Piaggi, Pablo M; Perego, Claudio; Parrinello, Michele
2018-04-04
Canonical molecular dynamics simulations of crystal growth from solution suffer from severe finite-size effects. As the crystal grows, the solute molecules are drawn from the solution to the crystal, leading to a continuous drop in the solution concentration. This is in contrast to experiments in which the crystal grows at an approximately constant supersaturation of a bulk solution. Recently, Perego et al. [ J. Chem. Phys. 2015, 142, 144113] showed that in a periodic setup in which the crystal is represented as a slab, the concentration in the vicinity of the two surfaces can be kept constant while the molecules are drawn from a part of the solution that acts as a molecular reservoir. This method is quite effective in studying crystallization under controlled supersaturation conditions. However, once the reservoir is depleted, the constant supersaturation conditions cannot be maintained. We propose a variant of this method to tackle this depletion problem by simultaneously dissolving one side of the crystal while letting the other side grow. A continuous supply of particles to the solution due to the crystal dissolution maintains a steady solution concentration and avoids reservoir depletion. In this way, a constant supersaturation condition can be maintained for as long as necessary. We have applied this method to study the growth and dissolution of urea crystal from water solution under constant supersaturation and undersaturation conditions, respectively. The computed growth and dissolution rates are in good agreement with those obtained in previous studies.
International Nuclear Information System (INIS)
Sundararaman, Ravishankar; Goddard, William A. III; Arias, Tomas A.
2017-01-01
First-principles calculations combining density-functional theory and continuum solvation models enable realistic theoretical modeling and design of electrochemical systems. When a reaction proceeds in such systems, the number of electrons in the portion of the system treated quantum mechanically changes continuously, with a balancing charge appearing in the continuum electrolyte. A grand-canonical ensemble of electrons at a chemical potential set by the electrode potential is therefore the ideal description of such systems that directly mimics the experimental condition. We present two distinct algorithms: a self-consistent field method and a direct variational free energy minimization method using auxiliary Hamiltonians (GC-AuxH), to solve the Kohn-Sham equations of electronic density-functional theory directly in the grand canonical ensemble at fixed potential. Both methods substantially improve performance compared to a sequence of conventional fixed-number calculations targeting the desired potential, with the GC-AuxH method additionally exhibiting reliable and smooth exponential convergence of the grand free energy. Lastly, we apply grand-canonical density-functional theory to the under-potential deposition of copper on platinum from chloride-containing electrolytes and show that chloride desorption, not partial copper monolayer formation, is responsible for the second voltammetric peak.
Sundararaman, Ravishankar; Goddard, William A.; Arias, Tomas A.
2017-03-01
First-principles calculations combining density-functional theory and continuum solvation models enable realistic theoretical modeling and design of electrochemical systems. When a reaction proceeds in such systems, the number of electrons in the portion of the system treated quantum mechanically changes continuously, with a balancing charge appearing in the continuum electrolyte. A grand-canonical ensemble of electrons at a chemical potential set by the electrode potential is therefore the ideal description of such systems that directly mimics the experimental condition. We present two distinct algorithms: a self-consistent field method and a direct variational free energy minimization method using auxiliary Hamiltonians (GC-AuxH), to solve the Kohn-Sham equations of electronic density-functional theory directly in the grand canonical ensemble at fixed potential. Both methods substantially improve performance compared to a sequence of conventional fixed-number calculations targeting the desired potential, with the GC-AuxH method additionally exhibiting reliable and smooth exponential convergence of the grand free energy. Finally, we apply grand-canonical density-functional theory to the under-potential deposition of copper on platinum from chloride-containing electrolytes and show that chloride desorption, not partial copper monolayer formation, is responsible for the second voltammetric peak.
Grand canonical simulations of hard-disk systems by simulated tempering
DEFF Research Database (Denmark)
Döge, G.; Mecke, K.; Møller, Jesper
2004-01-01
The melting transition of hard disks in two dimensions is still an unsolved problem and improved simulation algorithms may be helpful for its investigation. We suggest the application of simulating tempering for grand canonical hard-disk systems as an efficient alternative to the commonly......-used Monte Carlo algorithms for canonical systems. This approach allows the direct study of the packing fraction as a function of the chemical potential even in the vicinity of the melting transition. Furthermore, estimates of several spatial characteristics including pair correlation function are studied...
Finite temperature grand canonical ensemble study of the minimum electrophilicity principle.
Miranda-Quintana, Ramón Alain; Chattaraj, Pratim K; Ayers, Paul W
2017-09-28
We analyze the minimum electrophilicity principle of conceptual density functional theory using the framework of the finite temperature grand canonical ensemble. We provide support for this principle, both for the cases of systems evolving from a non-equilibrium to an equilibrium state and for the change from one equilibrium state to another. In doing so, we clearly delineate the cases where this principle can, or cannot, be used.
International Nuclear Information System (INIS)
Pogosian, S.
1981-01-01
It is known that in the grand canonical ensemble (for the case of small density of particles) the fluctuations (approximately mod(Λ)sup(1/2)) in the particle number have an asymptotic normal distribution as Λ→infinity. A similar statement holds for the distribution of the particle number in a bounded domain evaluated with respect to the limiting Gibbs distribution. The author obtains an asymptotic expansion in the local limit theorem for the particle number in the grand canonical ensemble, by using the asymptotic expansion of the grand canonical partition function. The coefficients of this expansion are not constants but depend on the form of the domain Λ. More precisely, they are constant up to a correction which is small (for large Λ). The author obtains an explicit form for the second term of the asymptotic expansion in the local limit theorem for the particle number, and also gets the first correction terms for the coefficients of this expansion. (Auth.)
Isobars of an ideal Bose gas within the grand canonical ensemble
International Nuclear Information System (INIS)
Jeon, Imtak; Park, Jeong-Hyuck; Kim, Sang-Woo
2011-01-01
We investigate the isobar of an ideal Bose gas confined in a cubic box within the grand canonical ensemble for a large yet finite number of particles, N. After solving the equation of the spinodal curve, we derive precise formulas for the supercooling and the superheating temperatures that reveal an N -1/3 or N -1/4 power correction to the known Bose-Einstein condensation temperature in the thermodynamic limit. Numerical computations confirm the accuracy of our analytical approximation, and further show that the isobar zigzags on the temperature-volume plane if N≥14 393. In particular, for the Avogadro's number of particles, the volume expands discretely about 10 5 times. Our results quantitatively agree with a previous study on the canonical ensemble within 0.1% error.
Alternative Hamiltonian for molecular dynamics simulations in the grand canonical ensemble
International Nuclear Information System (INIS)
Lo, C.; Palmer, B.
1995-01-01
An alternative to the Hamiltonian of Cagin and Pettitt for performing molecular dynamics simulations in the grand canonical ensemble is presented and used as the basis for a new algorithm. The algorithm is tested on the ideal gas and the truncated and shifted Lennard-Jones fluid. Simulations are used to calculate the vapor--liquid coexistence points for the Lennard-Jones system and are found to be in agreement with previous calculations using Gibbs ensemble calculations and with the Nicolas equation of state. Simulations are also performed on the Lennard-Jones solid
Pool, René; Heringa, Jaap; Hoefling, Martin; Schulz, Roland; Smith, Jeremy C; Feenstra, K Anton
2012-05-05
We report on a python interface to the GROMACS molecular simulation package, GromPy (available at https://github.com/GromPy). This application programming interface (API) uses the ctypes python module that allows function calls to shared libraries, for example, written in C. To the best of our knowledge, this is the first reported interface to the GROMACS library that uses direct library calls. GromPy can be used for extending the current GROMACS simulation and analysis modes. In this work, we demonstrate that the interface enables hybrid Monte-Carlo/molecular dynamics (MD) simulations in the grand-canonical ensemble, a simulation mode that is currently not implemented in GROMACS. For this application, the interplay between GromPy and GROMACS requires only minor modifications of the GROMACS source code, not affecting the operation, efficiency, and performance of the GROMACS applications. We validate the grand-canonical application against MD in the canonical ensemble by comparison of equations of state. The results of the grand-canonical simulations are in complete agreement with MD in the canonical ensemble. The python overhead of the grand-canonical scheme is only minimal. Copyright © 2012 Wiley Periodicals, Inc.
Delle Site, Luigi
2018-01-01
A theoretical scheme for the treatment of an open molecular system with electrons and nuclei is proposed. The idea is based on the Grand Canonical description of a quantum region embedded in a classical reservoir of molecules. Electronic properties of the quantum region are calculated at constant electronic chemical potential equal to that of the corresponding (large) bulk system treated at full quantum level. Instead, the exchange of molecules between the quantum region and the classical environment occurs at the chemical potential of the macroscopic thermodynamic conditions. The Grand Canonical Adaptive Resolution Scheme is proposed for the treatment of the classical environment; such an approach can treat the exchange of molecules according to first principles of statistical mechanics and thermodynamic. The overall scheme is build on the basis of physical consistency, with the corresponding definition of numerical criteria of control of the approximations implied by the coupling. Given the wide range of expertise required, this work has the intention of providing guiding principles for the construction of a well founded computational protocol for actual multiscale simulations from the electronic to the mesoscopic scale.
International Nuclear Information System (INIS)
Lee, S.J.; Mekjian, A.Z.
2004-01-01
Various phenomenological models of particle multiplicity distributions are discussed using a general form of a unified model which is based on the grand canonical partition function and Feynman's path integral approach to statistical processes. These models can be written as special cases of a more general distribution which has three control parameters which are a,x,z. The relation to these parameters to various physical quantities are discussed. A connection of the parameter a with Fisher's critical exponent τ is developed. Using this grand canonical approach, moments, cumulants and combinants are discussed and a physical interpretation of the combinants are given and their behavior connected to the critical exponent τ. Various physical phenomena such as hierarchical structure, void scaling relations, Koba-Nielson-Olesen or KNO scaling features, clan variables, and branching laws are shown in terms of this general approach. Several of these features which were previously developed in terms of the negative binomial distribution are found to be more general. Both hierarchical structure and void scaling relations depend on the Fisher exponent τ. Applications of our approach to the charged particle multiplicity distribution in jets of L3 and H1 data are given
A united event grand canonical Monte Carlo study of partially doped polyaniline
Energy Technology Data Exchange (ETDEWEB)
Byshkin, M. S., E-mail: mbyshkin@unisa.it, E-mail: gmilano@unisa.it; Correa, A. [Modeling Lab for Nanostructure and Catalysis, Dipartimento di Chimica e Biologia and NANOMATES, University of Salerno, 84084, via Ponte don Melillo, Fisciano Salerno (Italy); Buonocore, F. [ENEA Casaccia Research Center, Via Anguillarese 301, 00123 Rome (Italy); Di Matteo, A. [STMicroelectronics, Via Remo de Feo, 1 80022 Arzano, Naples (Italy); IMAST Scarl Piazza Bovio 22, 80133 Naples (Italy); Milano, G., E-mail: mbyshkin@unisa.it, E-mail: gmilano@unisa.it [Modeling Lab for Nanostructure and Catalysis, Dipartimento di Chimica e Biologia and NANOMATES, University of Salerno, 84084, via Ponte don Melillo, Fisciano Salerno (Italy); IMAST Scarl Piazza Bovio 22, 80133 Naples (Italy)
2013-12-28
A Grand Canonical Monte Carlo scheme, based on united events combining protonation/deprotonation and insertion/deletion of HCl molecules is proposed for the generation of polyaniline structures at intermediate doping levels between 0% (PANI EB) and 100% (PANI ES). A procedure based on this scheme and subsequent structure relaxations using molecular dynamics is described and validated. Using the proposed scheme and the corresponding procedure, atomistic models of amorphous PANI-HCl structures were generated and studied at different doping levels. Density, structure factors, and solubility parameters were calculated. Their values agree well with available experimental data. The interactions of HCl with PANI have been studied and distribution of their energies has been analyzed. The procedure has also been extended to the generation of PANI models including adsorbed water and the effect of inclusion of water molecules on PANI properties has also been modeled and discussed. The protocol described here is general and the proposed United Event Grand Canonical Monte Carlo scheme can be easily extended to similar polymeric materials used in gas sensing and to other systems involving adsorption and chemical reactions steps.
DEFF Research Database (Denmark)
Sloth, Peter
1993-01-01
The grand canonical ensemble has been used to study the evaluation of single ion activity coefficients in homogeneous ionic fluids. In this work, the Coulombic interactions are truncated according to the minimum image approximation, and the ions are assumed to be placed in a structureless......, homogeneous dielectric continuum. Grand canonical ensemble Monte Carlo calculation results for two primitive model electrolyte solutions are presented. Also, a formula involving the second moments of the total correlation functions is derived from fluctuation theory, which applies for the derivatives...... of the individual ionic activity coefficients with respect to the total ionic concentration. This formula has previously been proposed on the basis of somewhat different considerations....
Grand Canonical Monte Carlo simulations of hydrogen adsorption on aluminophosphate molecular sieves
Energy Technology Data Exchange (ETDEWEB)
Song, Mee Kyung [Bioinformatics and Molecular Design Research Center, B138A, Yonsei Engineering Research Complex, Yonsei University, Seoul 120-749 (Korea); No, Kyoung Tai [Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749 (Korea)
2009-03-15
The hydrogen adsorption simulations were carried for several model AlPOs (VPI-5, AlPO-5, AlPO-11 and AlPO-25) employing the Grand Canonical Monte Carlo (GCMC) simulations at 77 K to investigate the effect of pore size and the pore volume on the hydrogen uptake. The adsorption capacity showed no relationship with the pore size, surface area and micropore volume of AlPOs. However, the adsorption capacity per unit micropore volume increased as the pore size decreases. The heat of adsorption also increased as the pore size decreases. For all model AlPOs, the hydrogen exists homogeneously near the oxygen atoms in the framework. (author)
Spherical grand-canonical minority games with and without score discounting
International Nuclear Information System (INIS)
Bladon, Alex; Richardson, Thomas; Galla, Tobias
2009-01-01
We present a spherical version of the grand-canonical minority game (GCMG) and solve its dynamics in the stationary state. The model displays several types of transitions between multiple ergodic phases and one non-ergodic phase. We derive analytical solutions, including exact expressions for the volatility, throughout all ergodic phases and compute the phase behaviour of the system. In contrast to conventional GCMGs, where the introduction of memory loss precludes analytical approaches, the spherical model can also be solved when exponential discounting is taken into account. For the case of homogeneous incentives to trade ε and memory-loss rates ρ, an efficient phase is found only if ρ = ε = 0. Allowing for heterogeneous memory-loss rates we find that efficiency can be achieved as long as there is any finite fraction of agents which is not subject to memory loss
pH in Grand Canonical Statistics of an Electrochemical Interface
DEFF Research Database (Denmark)
Hansen, Martin Hangaard; Rossmeisl, Jan
2016-01-01
We present an atomic-scale model of the electrochemical interface, which unfolds the effects of pH and electrode potential using a generalized computational hydrogen electrode. The liquid structure of the solvent is included with the use of ab initio molecular dynamics to sample thousands...... of microstates with varying numbers of protons and electrons. The grand canonical probability weight function at constant pH and electrode potential is calculated a posteriori. The only inputs to the model are the fundamental assumptions of an equilibrated solvent, charge neutrality of the interface......, and the dimensions of the system. The structures are unbiased outputs, and several atomic-scale quantities are calculated for our model system, water/Au(111), as weighted averages. We present the potentials of zero charge, Gibbs isotherms, and differential capacities as a function of pH. The potential of maximum...
Simulating prescribed particle densities in the grand canonical ensemble using iterative algorithms.
Malasics, Attila; Gillespie, Dirk; Boda, Dezso
2008-03-28
We present two efficient iterative Monte Carlo algorithms in the grand canonical ensemble with which the chemical potentials corresponding to prescribed (targeted) partial densities can be determined. The first algorithm works by always using the targeted densities in the kT log(rho(i)) (ideal gas) terms and updating the excess chemical potentials from the previous iteration. The second algorithm extrapolates the chemical potentials in the next iteration from the results of the previous iteration using a first order series expansion of the densities. The coefficients of the series, the derivatives of the densities with respect to the chemical potentials, are obtained from the simulations by fluctuation formulas. The convergence of this procedure is shown for the examples of a homogeneous Lennard-Jones mixture and a NaCl-CaCl(2) electrolyte mixture in the primitive model. The methods are quite robust under the conditions investigated. The first algorithm is less sensitive to initial conditions.
International Nuclear Information System (INIS)
Luque, Noelia B.; Reinaudi, Luis; Serra, Pablo; Leiva, Ezequiel P.M.
2009-01-01
A thermodynamic analysis is performed on electrochemical metal deposition in the cavity of a foreign substrate. In particular, the deposition of Cu and Ag in nanometer-sized holes on Au(1 1 1) is studied by means of off-lattice atomistic Grand Canonical Monte Carlo simulations, using embedded atom method potentials. The present simulation conditions emulate experiments of electrochemical metal deposition in nanocavities, as performed in the literature. Depending on the system, remarkable differences are found in the way in which the defects are decorated, as well as in their energetics. When the interaction of the adsorbate atoms with the substrate is less favorable than the bulk interaction of the adsorbate, clusters are found that grow stepwise over the level of the surface. In the opposite case, the filling of the cavity occurs stepwise, without the occurrence of cluster growth above the surface level. The results of the simulations present a good qualitative agreement with experimental results from the literature
O'Keeffe, C J; Ren, Ruichao; Orkoulas, G
2007-11-21
Spatial updating grand canonical Monte Carlo algorithms are generalizations of random and sequential updating algorithms for lattice systems to continuum fluid models. The elementary steps, insertions or removals, are constructed by generating points in space either at random (random updating) or in a prescribed order (sequential updating). These algorithms have previously been developed only for systems of impenetrable spheres for which no particle overlap occurs. In this work, spatial updating grand canonical algorithms are generalized to continuous, soft-core potentials to account for overlapping configurations. Results on two- and three-dimensional Lennard-Jones fluids indicate that spatial updating grand canonical algorithms, both random and sequential, converge faster than standard grand canonical algorithms. Spatial algorithms based on sequential updating not only exhibit the fastest convergence but also are ideal for parallel implementation due to the absence of strict detailed balance and the nature of the updating that minimizes interprocessor communication. Parallel simulation results for three-dimensional Lennard-Jones fluids show a substantial reduction of simulation time for systems of moderate and large size. The efficiency improvement by parallel processing through domain decomposition is always in addition to the efficiency improvement by sequential updating.
International Nuclear Information System (INIS)
Zmushko, V.V.; Migdal, A.A.
1987-01-01
A model of triangulated random surfaces which is the discrete analogue of the Polyakov string is considered in the work. An algorithm is proposed which enables one to study the model by means of the Monte Carlo method in the grand canonical ensemble. Preliminary results are presented on the evaluation of the critical index γ
Binder, Moritz; Barthel, Thomas
Based on DMRG, strongly correlated quantum many-body systems at finite temperatures can be simulated by sampling over a certain class of pure matrix product states (MPS) called minimally entangled typical thermal states (METTS). Here, we show how symmetries of the system can be exploited to considerably reduce computation costs in the METTS algorithm. While this is straightforward for the canonical ensemble, we introduce a modification of the algorithm to efficiently simulate the grand-canonical ensemble under utilization of symmetries. In addition, we construct novel symmetry-conserving collapse bases for the transitions in the Markov chain of METTS that improve the speed of convergence of the algorithm by reducing autocorrelations.
Thermodynamics of Born-Infeld-anti-de Sitter black holes in the grand canonical ensemble
International Nuclear Information System (INIS)
Fernando, Sharmanthie
2006-01-01
The main objective of this paper is to study thermodynamics and stability of static electrically charged Born-Infeld black holes in AdS space in D=4. The Euclidean action for the grand canonical ensemble is computed with the appropriate boundary terms. The thermodynamical quantities such as the Gibbs free energy, entropy and specific heat of the black holes are derived from it. The global stability of black holes are studied in detail by studying the free energy for various potentials. For small values of the potential, we find that there is a Hawking-Page phase transition between a BIAdS black hole and the thermal-AdS space. For large potentials, the black hole phase is dominant and is preferred over the thermal-AdS space. Local stability is studied by computing the specific heat for constant potentials. The nonextreme black holes have two branches: small black holes are unstable and the large black holes are stable. The extreme black holes are shown to be stable both globally as well as locally. In addition to the thermodynamics, we also show that the phase structure relating the mass M and the charge Q of the black holes is similar to the liquid-gas-solid phase diagram
Shadrack Jabes, B.; Krekeler, C.; Klein, R.; Delle Site, L.
2018-05-01
We employ the Grand Canonical Adaptive Resolution Simulation (GC-AdResS) molecular dynamics technique to test the spatial locality of the 1-ethyl 3-methyl imidazolium chloride liquid. In GC-AdResS, atomistic details are kept only in an open sub-region of the system while the environment is treated at coarse-grained level; thus, if spatial quantities calculated in such a sub-region agree with the equivalent quantities calculated in a full atomistic simulation, then the atomistic degrees of freedom outside the sub-region play a negligible role. The size of the sub-region fixes the degree of spatial locality of a certain quantity. We show that even for sub-regions whose radius corresponds to the size of a few molecules, spatial properties are reasonably reproduced thus suggesting a higher degree of spatial locality, a hypothesis put forward also by other researchers and that seems to play an important role for the characterization of fundamental properties of a large class of ionic liquids.
Effect of Pore Geometry on Gas Adsorption: Grand Canonical Monte Carlo Simulation Studies
International Nuclear Information System (INIS)
Lee, Eon Ji; Chang, Rak Woo; Han, Ji Hyung; Chung, Taek Dong
2012-01-01
In this study, we investigated the pure geometrical effect of porous materials in gas adsorption using the grand canonical Monte Carlo simulations of primitive gas-pore models with various pore geometries such as planar, cylindrical, and random pore geometries. Although the model does not possess atomistic level details of porous materials, our simulation results provided many insightful information in the effect of pore geometry on the adsorption behavior of gas molecules. First, the surface curvature of porous materials plays a significant role in the amount of adsorbed gas molecules: the concave surface such as in cylindrical pores induces more attraction between gas molecules and pore, which results in the enhanced gas adsorption. On the contrary, the convex surface of random pores gives the opposite effect. Second, this geometrical effect shows a nonmonotonic dependence on the gas-pore interaction strength and length. Third, as the external gas pressure is increased, the change in the gas adsorption due to pore geometry is reduced. Finally, the pore geometry also affects the collision dynamics of gas molecules. Since our model is based on primitive description of fluid molecules, our conclusion can be applied to any fluidic systems including reactant-electrode systems
A Grand Canonical Monte Carlo Molecular Study of a Weak Polyampholyte
Jimenez, Arturo Martinez
2016-05-01
Over the last few decades, there has been an increasing interest in the study of charged polymers for applications such as desalination of water, flocculation, sewage treatment, and enhanced oil recovery. Polyelectrolyte chains containing both positively and negatively charged units (polyampholytes) have been recently studied as viscosity-control agents in enhanced oil recovery, and as entrapping macromolecules for protection and delayed release of enzymes in hydraulic fracturing. In this study we performed Monte Carlo molecular simulations in a grand canonical ensemble to study the behavior of a weak polyampholyte in a dilute regime. Weak polyampholytes have the ability to dissociate in a limited pH, which makes them interesting for applications that require a pH-triggerable response. The titration behaviors of diblock and random polyampholytes are simulated as a function of solvent quality, electrostatic strength, and salt concentration. For diblock polyampholyte chains in hydrophobic solvents, transition between tadpole-like and globule conformation occurs with variations in the solution pH. Random polyampholytes present extended, globule, and pearl-necklace conformations at different solvent conditions and pH values. At high ionic strength, electrostatic interactions in the polyampholytes become screened and the chains are mostly in globule state.
Electrolyte pore/solution partitioning by expanded grand canonical ensemble Monte Carlo simulation
Energy Technology Data Exchange (ETDEWEB)
Moucka, Filip [Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia 23221 (United States); Faculty of Science, J. E. Purkinje University, 400 96 Ústí nad Labem (Czech Republic); Bratko, Dusan, E-mail: dbratko@vcu.edu; Luzar, Alenka, E-mail: aluzar@vcu.edu [Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia 23221 (United States)
2015-03-28
Using a newly developed grand canonical Monte Carlo approach based on fractional exchanges of dissolved ions and water molecules, we studied equilibrium partitioning of both components between laterally extended apolar confinements and surrounding electrolyte solution. Accurate calculations of the Hamiltonian and tensorial pressure components at anisotropic conditions in the pore required the development of a novel algorithm for a self-consistent correction of nonelectrostatic cut-off effects. At pore widths above the kinetic threshold to capillary evaporation, the molality of the salt inside the confinement grows in parallel with that of the bulk phase, but presents a nonuniform width-dependence, being depleted at some and elevated at other separations. The presence of the salt enhances the layered structure in the slit and lengthens the range of inter-wall pressure exerted by the metastable liquid. Solvation pressure becomes increasingly repulsive with growing salt molality in the surrounding bath. Depending on the sign of the excess molality in the pore, the wetting free energy of pore walls is either increased or decreased by the presence of the salt. Because of simultaneous rise in the solution surface tension, which increases the free-energy cost of vapor nucleation, the rise in the apparent hydrophobicity of the walls has not been shown to enhance the volatility of the metastable liquid in the pores.
Malasics, Attila; Boda, Dezso
2010-06-28
Two iterative procedures have been proposed recently to calculate the chemical potentials corresponding to prescribed concentrations from grand canonical Monte Carlo (GCMC) simulations. Both are based on repeated GCMC simulations with updated excess chemical potentials until the desired concentrations are established. In this paper, we propose combining our robust and fast converging iteration algorithm [Malasics, Gillespie, and Boda, J. Chem. Phys. 128, 124102 (2008)] with the suggestion of Lamperski [Mol. Simul. 33, 1193 (2007)] to average the chemical potentials in the iterations (instead of just using the chemical potentials obtained in the last iteration). We apply the unified method for various electrolyte solutions and show that our algorithm is more efficient if we use the averaging procedure. We discuss the convergence problems arising from violation of charge neutrality when inserting/deleting individual ions instead of neutral groups of ions (salts). We suggest a correction term to the iteration procedure that makes the algorithm efficient to determine the chemical potentials of individual ions too.
Electrolyte pore/solution partitioning by expanded grand canonical ensemble Monte Carlo simulation
International Nuclear Information System (INIS)
Moucka, Filip; Bratko, Dusan; Luzar, Alenka
2015-01-01
Using a newly developed grand canonical Monte Carlo approach based on fractional exchanges of dissolved ions and water molecules, we studied equilibrium partitioning of both components between laterally extended apolar confinements and surrounding electrolyte solution. Accurate calculations of the Hamiltonian and tensorial pressure components at anisotropic conditions in the pore required the development of a novel algorithm for a self-consistent correction of nonelectrostatic cut-off effects. At pore widths above the kinetic threshold to capillary evaporation, the molality of the salt inside the confinement grows in parallel with that of the bulk phase, but presents a nonuniform width-dependence, being depleted at some and elevated at other separations. The presence of the salt enhances the layered structure in the slit and lengthens the range of inter-wall pressure exerted by the metastable liquid. Solvation pressure becomes increasingly repulsive with growing salt molality in the surrounding bath. Depending on the sign of the excess molality in the pore, the wetting free energy of pore walls is either increased or decreased by the presence of the salt. Because of simultaneous rise in the solution surface tension, which increases the free-energy cost of vapor nucleation, the rise in the apparent hydrophobicity of the walls has not been shown to enhance the volatility of the metastable liquid in the pores
Limit order book and its modeling in terms of Gibbs Grand-Canonical Ensemble
Bicci, Alberto
2016-12-01
In the domain of so called Econophysics some attempts have been already made for applying the theory of thermodynamics and statistical mechanics to economics and financial markets. In this paper a similar approach is made from a different perspective, trying to model the limit order book and price formation process of a given stock by the Grand-Canonical Gibbs Ensemble for the bid and ask orders. The application of the Bose-Einstein statistics to this ensemble allows then to derive the distribution of the sell and buy orders as a function of price. As a consequence we can define in a meaningful way expressions for the temperatures of the ensembles of bid orders and of ask orders, which are a function of minimum bid, maximum ask and closure prices of the stock as well as of the exchanged volume of shares. It is demonstrated that the difference between the ask and bid orders temperatures can be related to the VAO (Volume Accumulation Oscillator), an indicator empirically defined in Technical Analysis of stock markets. Furthermore the derived distributions for aggregate bid and ask orders can be subject to well defined validations against real data, giving a falsifiable character to the model.
Li, Gu-Qiang; Mo, Jie-Xiong
2016-06-01
The phase transition of a four-dimensional charged AdS black hole solution in the R +f (R ) gravity with constant curvature is investigated in the grand canonical ensemble, where we find novel characteristics quite different from that in the canonical ensemble. There exists no critical point for T -S curve while in former research critical point was found for both the T -S curve and T -r+ curve when the electric charge of f (R ) black holes is kept fixed. Moreover, we derive the explicit expression for the specific heat, the analog of volume expansion coefficient and isothermal compressibility coefficient when the electric potential of f (R ) AdS black hole is fixed. The specific heat CΦ encounters a divergence when 0 b . This finding also differs from the result in the canonical ensemble, where there may be two, one or no divergence points for the specific heat CQ . To examine the phase structure newly found in the grand canonical ensemble, we appeal to the well-known thermodynamic geometry tools and derive the analytic expressions for both the Weinhold scalar curvature and Ruppeiner scalar curvature. It is shown that they diverge exactly where the specific heat CΦ diverges.
Grand canonical Monte Carlo simulation study of capillary condensation between nanoparticles.
Kim, Seonmin; Ehrman, Sheryl H
2007-10-07
Capillary condensation at the nanoscale differs from condensation in the bulk phase, because it is a strong function of surface geometry and gas-surface interactions. Here, the effects of geometry on the thermodynamics of capillary condensation at the neck region between nanoparticles are investigated via a grand canonical Monte Carlo simulation using a two-dimensional lattice gas model. The microscopic details of the meniscus formation on various surface geometries are examined and compared with results of classical macromolecular theory, the Kelvin equation. We assume that the system is composed of a lattice gas and the surfaces of two particles are approximated by various shapes. The system is modeled on the basis of the molecular properties of the particle surface and lattice gas in our system corresponding to titania nanoparticles and tetraethoxy orthosilicate molecules, respectively. This system was chosen in order to reasonably emulate our previous experimental results for capillary condensation on nanoparticle surfaces. Qualitatively, our simulation results show that the specific geometry in the capillary zone, the surface-surface distance, and the saturation ratio are important for determining the onset and broadening of the liquid meniscus. The meniscus height increases continuously as the saturation ratio increases and the meniscus broadens faster above the saturation ratio of 0.90. The change of the radius of curvature of the particle surface affects the dimensions of the capillary zone, which drives more condensation in narrow zones and less condensation in wide zones. The increase of surface-surface distance results in the decrease of the meniscus height or even the disappearance of the meniscus entirely at lower saturation ratios. These effects are significant at the nanoscale and must be carefully considered in order to develop predictive relationships for meniscus height as a function of saturation conditions.
Zeolite-templated carbon replica: a Grand Canonical Monte-Carlo simulation study
International Nuclear Information System (INIS)
Thomas Roussel; Roland J M Pellenq; Christophe Bichara; Roger Gadiou; Antoine Didion; Cathie Vix Guterl; Fabrice Gaslain; Julien Parmentier; Valentin Valtchev; Joel Patarin
2005-01-01
Microporous carbon materials are interesting for several applications such as hydrogen storage, catalysis or electrical double layer capacitors. The development of the negative templating method to obtain carbon replicas from ordered templates, has lead to the synthesis of several new materials which have interesting textural properties, attractive for energy storage. Among the possible templates, zeolites can be used to obtain highly microporous carbon materials. Nevertheless, the phenomena involved in the replica synthesis are not fully understood, and the relationships between the structure of the template, the carbon precursor and the resulting carbon material need to be investigated. Experimental results for carbon zeolite-templated nano-structures can be found in a series of papers; see for instance ref. [1] in which Wang et al describe a route to ultra-small Single Wall Carbon Nano-tubes (SWNTs) using the porosity of zeolite AlPO 4 -5. After matrix removal, the resulting structure is a free-standing bundle of 4 Angstroms large nano-tubes. However, it is highly desirable to obtain an ordered porous carbon structure that forms a real 3D network to be used for instance in gas storage applications. Carbon replica of faujasite and EMT zeolites can have these properties since these zeolites have a 3D porous network made of 10 Angstroms cages connected to each other through 7 Angstroms large windows. The first step of this study was to generate a theoretical carbon replica structure of various zeolites (faujasite, EMT, AlPO 4 -5, silicalite). For this purpose, we used the Grand Canonical Monte-Carlo (GCMC) technique in which the carbon-carbon interactions were described within the frame of a newly developed Tight Binding approach and the carbon-zeolite interactions assumed to be characteristic of physi-sorption. The intrinsic stability of the subsequent carbon nano-structures was then investigated after mimicking the removal of the inorganic phase by switching
Grand Canonical Investigation of the Quasi Liquid Layer of Ice: Is It Liquid?
Pickering, Ignacio; Paleico, Martin; Sirkin, Yamila A Perez; Scherlis, Damian A; Factorovich, Matías H
2018-05-10
In this study, the solid-vapor equilibrium and the quasi liquid layer (QLL) of ice Ih exposing the basal and primary prismatic faces were explored by means of grand canonical molecular dynamics simulations with the monatomic mW potential. For this model, the solid-vapor equilibrium was found to follow the Clausius-Clapeyron relation in the range examined, from 250 to 270 K, with a Δ H sub of 50 kJ/mol in excellent agreement with the experimental value. The phase diagram of the mW model was constructed for the low pressure region around the triple point. The analysis of the crystallization dynamics during condensation and evaporation revealed that, for the basal face, both processes are highly activated, and in particular cubic ice is formed during condensation, producing stacking-disordered ice. The basal and primary prismatic surfaces of ice Ih were investigated at different temperatures and at their corresponding equilibrium vapor pressures. Our results show that the region known as QLL can be interpreted as the outermost layers of the solid where a partial melting takes place. Solid islands in the nanometer length scale are surrounded by interconnected liquid areas, generating a bidimensional nanophase segregation that spans throughout the entire width of the outermost layer even at 250 K. Two approaches were adopted to quantify the QLL and discussed in light of their ability to reflect this nanophase segregation phenomena. Our results in the μVT ensemble were compared with NPT and NVT simulations for two system sizes. No significant differences were found between the results as a consequence of model system size or of the working ensemble. Nevertheless, certain advantages of performing μVT simulations in order to reproduce the experimental situation are highlighted. On the one hand, the QLL thickness measured out of equilibrium might be affected because of crystallization being slower than condensation. On the other, preliminary simulations of AFM
Zeolite-templated carbon replica: a grand canonical Monte-Carlo simulation study
International Nuclear Information System (INIS)
Roussel, Th.; Pellenq, R.J.M.; Bichara, Ch.; Gadiou, R.; Didion, A.; Vix-Guterl, C.; Gaslain, F.; Parmentier, J.; Valtchev, V.; Patarin, J.
2005-01-01
Microporous carbon materials are interesting for several applications such as hydrogen storage, catalysis or electrical double layer capacitors. The development of the negative templating method to obtain carbon replicas from ordered templates, has lead to the synthesis of several new materials which have interesting textural properties, attractive for energy storage. Among the possible templates, zeolites can be used to obtain highly microporous carbon materials. Nevertheless, the phenomena involved in the replica synthesis are not fully understood, and the relationships between the structure of the template, the carbon precursor and the resulting carbon material need to be investigated. Experimental results for carbon zeolite-templated nano-structures can be found in a series of papers; see for instance ref. [1] in which Wang et al describe a route to ultra-small Single Wall Carbon Nano-tubes (SWNTs) using the porosity of zeolite AlPO 4 -5. After matrix removal, the resulting structure is a free-standing bundle of 4 Angstroms large nano-tubes. However, it is highly desirable to obtain an ordered porous carbon structure that forms a real 3D network to be used for instance in gas storage applications. Carbon replica of faujasite and EMT zeolites can have these properties since these zeolites have a 3D porous network made of 10 Angstroms cages connected to each other through 7 Angstroms large windows. The first step of this study was to generate a theoretical carbon replica structure of various zeolites (faujasite, EMT, AlPO 4 -5, silicalite). For this purpose, we used the Grand Canonical Monte-Carlo (GCMC) technique in which the carbon-carbon interactions were described within the frame of a newly developed Tight Binding approach and the carbon-zeolite interactions assumed to be characteristic of physisorption. The intrinsic stability of the subsequent carbon nano-structures was then investigated after mimicking the removal of the inorganic phase by switching
Croteau, T; Bertram, A K; Patey, G N
2008-10-30
Grand canonical Monte Carlo calculations are used to determine water adsorption and structure on defect-free kaolinite surfaces as a function of relative humidity at 235 K. This information is then used to gain insight into ice nucleation on kaolinite surfaces. Results for both the SPC/E and TIP5P-E water models are compared and demonstrate that the Al-surface [(001) plane] and both protonated and unprotonated edges [(100) plane] strongly adsorb at atmospherically relevant relative humidities. Adsorption on the Al-surface exhibits properties of a first-order process with evidence of collective behavior, whereas adsorption on the edges is essentially continuous and appears dominated by strong water lattice interactions. For the protonated and unprotonated edges no structure that matches hexagonal ice is observed. For the Al-surface some of the water molecules formed hexagonal rings. However, the a o lattice parameter for these rings is significantly different from the corresponding constant for hexagonal ice ( Ih). A misfit strain of 14.0% is calculated between the hexagonal pattern of water adsorbed on the Al-surface and the basal plane of ice Ih. Hence, the ring structures that form on the Al-surface are not expected to be good building-blocks for ice nucleation due to the large misfit strain.
Energy Technology Data Exchange (ETDEWEB)
Agarwal, Animesh, E-mail: animesh@zedat.fu-berlin.de; Delle Site, Luigi, E-mail: dellesite@fu-berlin.de [Institute for Mathematics, Freie Universität Berlin, Berlin (Germany)
2015-09-07
Quantum effects due to the spatial delocalization of light atoms are treated in molecular simulation via the path integral technique. Among several methods, Path Integral (PI) Molecular Dynamics (MD) is nowadays a powerful tool to investigate properties induced by spatial delocalization of atoms; however, computationally this technique is very demanding. The above mentioned limitation implies the restriction of PIMD applications to relatively small systems and short time scales. One of the possible solutions to overcome size and time limitation is to introduce PIMD algorithms into the Adaptive Resolution Simulation Scheme (AdResS). AdResS requires a relatively small region treated at path integral level and embeds it into a large molecular reservoir consisting of generic spherical coarse grained molecules. It was previously shown that the realization of the idea above, at a simple level, produced reasonable results for toy systems or simple/test systems like liquid parahydrogen. Encouraged by previous results, in this paper, we show the simulation of liquid water at room conditions where AdResS, in its latest and more accurate Grand-Canonical-like version (GC-AdResS), is merged with two of the most relevant PIMD techniques available in the literature. The comparison of our results with those reported in the literature and/or with those obtained from full PIMD simulations shows a highly satisfactory agreement.
Valentini, Paolo; Schwartzentruber, Thomas E.; Cozmuta, Ioana
2011-12-01
Atomic-level Grand Canonical Monte Carlo (GCMC) simulations equipped with a reactive force field (ReaxFF) are used to study atomic oxygen adsorption on a Pt(111) surface. The off-lattice GCMC calculations presented here rely solely on the interatomic potential and do not necessitate the pre-computation of surface adlayer structures and their interpolation. As such, they provide a predictive description of adsorbate phases. In this study, validation is obtained with experimental evidence (steric heats of adsorption and isotherms) as well as DFT-based state diagrams available in the literature. The ReaxFF computed steric heats of adsorption agree well with experimental data, and this study clearly shows that indirect dissociative adsorption of O2 on Pt(111) is an activated process at non-zero coverages, with an activation energy that monotonically increases with coverage. At a coverage of 0.25 ML, a highly ordered p(2 × 2) adlayer is found, in agreement with several low-energy electron diffraction observations. Isotherms obtained from the GCMC simulations compare qualitatively and quantitatively well with previous DFT-based state diagrams, but are in disagreement with the experimental data sets available. ReaxFF GCMC simulations at very high coverages show that O atoms prefer to bind in fcc hollow sites, at least up to 0.8 ML considered in the present work. At moderate coverages, little to no disorder appears in the Pt lattice. At high coverages, some Pt atoms markedly protrude out of the surface plane. This observation is in qualitative agreement with recent STM images of an oxygen covered Pt surface. The use of the GCMC technique based on a transferable potential is particularly valuable to produce more realistic systems (adsorbent and adsorbate) to be used in subsequent dynamical simulations (Molecular Dynamics) to address recombination reactions (via either Eley-Rideal or Langmuir-Hinshelwood mechanisms) on variously covered surfaces. By using GCMC and Molecular
The Grand Bay National Estuarine Research Reserve has the highest biotic diversity of habitats and offer a reserve of food resources and commercially significant species. Rapid human civilization has led to accumulation of heavy metals and trace elements in estuaries. The Grand Bay National Estuarin...
Energy Technology Data Exchange (ETDEWEB)
Furmaniak, Sylwester; Terzyk, Artur P; Gauden, Piotr A [Department of Chemistry, Physicochemistry of Carbon Materials Research Group, N Copernicus University, Gagarin Street 7, 87-100 Torun (Poland); Kowalczyk, Piotr [Nanochemistry Research Institute, Curtin University, PO Box U1987, Perth, WA 6845 (Australia); Harris, Peter J F, E-mail: aterzyk@chem.uni.torun.pl [Centre for Advanced Microscopy, University of Reading, Whiteknights, Reading RG6 6AF (United Kingdom)
2011-10-05
Using grand canonical Monte Carlo simulation we show, for the first time, the influence of the carbon porosity and surface oxidation on the parameters of the Dubinin-Astakhov (DA) adsorption isotherm equation. We conclude that upon carbon surface oxidation, the adsorption decreases for all carbons studied. Moreover, the parameters of the DA model depend on the number of surface oxygen groups. That is why in the case of carbons containing surface polar groups, SF{sub 6} adsorption isotherm data cannot be used for characterization of the porosity. (paper)
Carmelo, J. M. P.; Prosen, T.
2017-01-01
Whether in the thermodynamic limit, vanishing magnetic field h → 0, and nonzero temperature the spin stiffness of the spin-1/2 XXX Heisenberg chain is finite or vanishes within the grand-canonical ensemble remains an unsolved and controversial issue, as different approaches yield contradictory results. Here we provide an upper bound on the stiffness and show that within that ensemble it vanishes for h → 0 in the thermodynamic limit of chain length L → ∞, at high temperatures T → ∞. Our approach uses a representation in terms of the L physical spins 1/2. For all configurations that generate the exact spin-S energy and momentum eigenstates such a configuration involves a number 2S of unpaired spins 1/2 in multiplet configurations and L - 2 S spins 1/2 that are paired within Msp = L / 2 - S spin-singlet pairs. The Bethe-ansatz strings of length n = 1 and n > 1 describe a single unbound spin-singlet pair and a configuration within which n pairs are bound, respectively. In the case of n > 1 pairs this holds both for ideal and deformed strings associated with n complex rapidities with the same real part. The use of such a spin 1/2 representation provides useful physical information on the problem under investigation in contrast to often less controllable numerical studies. Our results provide strong evidence for the absence of ballistic transport in the spin-1/2 XXX Heisenberg chain in the thermodynamic limit, for high temperatures T → ∞, vanishing magnetic field h → 0 and within the grand-canonical ensemble.
Directory of Open Access Journals (Sweden)
J.M.P. Carmelo
2017-01-01
Full Text Available Whether in the thermodynamic limit, vanishing magnetic field h→0, and nonzero temperature the spin stiffness of the spin-1/2 XXX Heisenberg chain is finite or vanishes within the grand-canonical ensemble remains an unsolved and controversial issue, as different approaches yield contradictory results. Here we provide an upper bound on the stiffness and show that within that ensemble it vanishes for h→0 in the thermodynamic limit of chain length L→∞, at high temperatures T→∞. Our approach uses a representation in terms of the L physical spins 1/2. For all configurations that generate the exact spin-S energy and momentum eigenstates such a configuration involves a number 2S of unpaired spins 1/2 in multiplet configurations and L−2S spins 1/2 that are paired within Msp=L/2−S spin–singlet pairs. The Bethe-ansatz strings of length n=1 and n>1 describe a single unbound spin–singlet pair and a configuration within which n pairs are bound, respectively. In the case of n>1 pairs this holds both for ideal and deformed strings associated with n complex rapidities with the same real part. The use of such a spin 1/2 representation provides useful physical information on the problem under investigation in contrast to often less controllable numerical studies. Our results provide strong evidence for the absence of ballistic transport in the spin-1/2 XXX Heisenberg chain in the thermodynamic limit, for high temperatures T→∞, vanishing magnetic field h→0 and within the grand-canonical ensemble.
International Nuclear Information System (INIS)
Terzyk, Artur P; Furmaniak, Sylwester; Gauden, Piotr A; Harris, Peter J F; Wloch, Jerzy
2008-01-01
Using the plausible model of activated carbon proposed by Harris and co-workers and grand canonical Monte Carlo simulations, we study the applicability of standard methods for describing adsorption data on microporous carbons widely used in adsorption science. Two carbon structures are studied, one with a small distribution of micropores in the range up to 1 nm, and the other with micropores covering a wide range of porosity. For both structures, adsorption isotherms of noble gases (from Ne to Xe), carbon tetrachloride and benzene are simulated. The data obtained are considered in terms of Dubinin-Radushkevich plots. Moreover, for benzene and carbon tetrachloride the temperature invariance of the characteristic curve is also studied. We show that using simulated data some empirical relationships obtained from experiment can be successfully recovered. Next we test the applicability of Dubinin's related models including the Dubinin-Izotova, Dubinin-Radushkevich-Stoeckli, and Jaroniec-Choma equations. The results obtained demonstrate the limits and applications of the models studied in the field of carbon porosity characterization
International Nuclear Information System (INIS)
Bian Liang; Shu Yuan-Jie; Wang Xin-Feng
2012-01-01
Amorphous and crystalline poly (chloro-p-xylylene) (PPX C) membranes are constructed by using a novel computational technique, that is, a combined method of NVT+NPT-molecular dynamics (MD) and gradually reducing the size (GRS) methods. The related free volumes are defined as homology clusters. Then the sorption and the permeation of gases in PPX C polymers are studied using grand canonical Monte Carlo (GCMC) and NVT-MD methods. The results show that the crystalline PPX C membranes provide smaller free volumes for absorbing or transferring gases relative to the amorphous PPX C area. The gas sorption in PPX C membranes mainly belongs to the physical one, and H bonds can appear obviously in the amorphous area. By cluster analyzing on the mean square displacement of gases, we find that gases walk along the x axis in the crystalline area and walk randomly in the amorphous area. The calculated permeability coefficients are close to the experimental data. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)
Madurga, Sergio; Rey-Castro, Carlos; Pastor, Isabel; Vilaseca, Eudald; David, Calin; Garcés, Josep Lluís; Puy, Jaume; Mas, Francesc
2011-11-14
In this paper, we present a computer simulation study of the ion binding process at an ionizable surface using a semi-grand canonical Monte Carlo method that models the surface as a discrete distribution of charged and neutral functional groups in equilibrium with explicit ions modelled in the context of the primitive model. The parameters of the simulation model were tuned and checked by comparison with experimental titrations of carboxylated latex particles in the presence of different ionic strengths of monovalent ions. The titration of these particles was analysed by calculating the degree of dissociation of the latex functional groups vs. pH curves at different background salt concentrations. As the charge of the titrated surface changes during the simulation, a procedure to keep the electroneutrality of the system is required. Here, two approaches are used with the choice depending on the ion selected to maintain electroneutrality: counterion or coion procedures. We compare and discuss the difference between the procedures. The simulations also provided a microscopic description of the electrostatic double layer (EDL) structure as a function of pH and ionic strength. The results allow us to quantify the effect of the size of the background salt ions and of the surface functional groups on the degree of dissociation. The non-homogeneous structure of the EDL was revealed by plotting the counterion density profiles around charged and neutral surface functional groups. © 2011 American Institute of Physics
Directory of Open Access Journals (Sweden)
Meagan C Small
Full Text Available Resistance to macrolide antibiotics is conferred by mutation of A2058 to G or methylation by Erm methyltransferases of the exocyclic N6 of A2058 (E. coli numbering that forms the macrolide binding site in the 50S subunit of the ribosome. Ketolides such as telithromycin mitigate A2058G resistance yet remain susceptible to Erm-based resistance. Molecular details associated with macrolide resistance due to the A2058G mutation and methylation at N6 of A2058 by Erm methyltransferases were investigated using empirical force field-based simulations. To address the buried nature of the macrolide binding site, the number of waters within the pocket was allowed to fluctuate via the use of a Grand Canonical Monte Carlo (GCMC methodology. The GCMC water insertion/deletion steps were alternated with Molecular Dynamics (MD simulations to allow for relaxation of the entire system. From this GCMC/MD approach information on the interactions between telithromycin and the 50S ribosome was obtained. In the wild-type (WT ribosome, the 2'-OH to A2058 N1 hydrogen bond samples short distances with a higher probability, while the effectiveness of telithromycin against the A2058G mutation is explained by a rearrangement of the hydrogen bonding pattern of the 2'-OH to 2058 that maintains the overall antibiotic-ribosome interactions. In both the WT and A2058G mutation there is significant flexibility in telithromycin's imidazole-pyridine side chain (ARM, indicating that entropic effects contribute to the binding affinity. Methylated ribosomes show lower sampling of short 2'-OH to 2058 distances and also demonstrate enhanced G2057-A2058 stacking leading to disrupted A752-U2609 Watson-Crick (WC interactions as well as hydrogen bonding between telithromycin's ARM and U2609. This information will be of utility in the rational design of novel macrolide analogs with improved activity against methylated A2058 ribosomes.
Energy Technology Data Exchange (ETDEWEB)
Abdelatif, H., E-mail: habdelatif@usthb.dz; Drir, M., E-mail: mdrir@usthb.dz
2016-11-10
Highlights: • Finite number of layers, at saturated pressure, is found for low temperatures. • A layer is represented by a sharp step which is a first order phase transition. • A thin film to thick film transition around the triple point is observed. • Temperatures and relative pressures of layers formation and phase diagrams are given. - Abstract: We study the phase transitions in adsorbed multilayers by Grand Canonical Monte Carlo simulations (GCMC) of the lattice-gas model. The focus will be on ethylene (C{sub 2}H{sub 4}) and tetrafluoromethane (CF{sub 4}) on a homogeneous graphite surface. Earlier simulations of these systems investigated structural properties, dynamical behaviors of adsorbed films and thermodynamic quantities such as isosteric heat. The main purpose of this study is to consider the adsorbed multilayers by the evaluation of the layering behavior, the wetting phenomena and the critical temperatures. The isotherms obtained for temperature from 50 K to 170 K reproduce a number of interesting features observed experimentally: (i) we observe an important number of layers in contrast with previous simulations, (ii) a finite number of layers at saturated pressure for low temperatures are found, (iii) the isotherms present vertical steps typical of layer-by-layer growth, at higher temperatures these distinct layers tend to disappear signifying that the film thickness increases continuously, (iv) a thin film to thick film transition near the triple point temperature is noticed. In addition to this qualitative description, quantitative information are determined including temperatures and relative pressures of layers formation, layer-critical-point temperatures and phase diagrams. Comparing the two systems, ethylene/graphite and tetrafluoromethane/graphite, we observe a qualitatively similar behavior.
Horowitz, A.J.; Elrick, K.A.; Smith, J.J.
2001-01-01
Suspended sediment, sediment-associated, total trace element, phosphorus (P), and total organic carbon (TOC) fluxes were determined for the Mississippi, Columbia, Rio Grande, and Colorado Basins for the study period (the 1996, 1997, and 1998 water years) as part of the US Geological Survey's redesigned National Stream Quality Accounting Network (NASQAN) programme. The majority (??? 70%) of Cu, Zn, Cr, Ni, Ba, P, As, Fe, Mn, and Al are transported in association with suspended sediment; Sr transport seems dominated by the dissolved phase, whereas the transport of Li and TOC seems to be divided equally between both phases. Average dissolved trace element levels are markedly lower than reported during the original NASQAN programme; this seems due to the use of 'clean' sampling, processing, and analytical techniques rather than to improvements in water quality. Partitioning between sediment and water for Ag, Pb, Cd, Cr, Co, V, Be, As, Sb, Hg, and Ti could not be estimated due to a lack of detectable dissolved concentrations in most samples. Elevated suspended sediment-associated Zn levels were detected in the Ohio River Basin and elevated Hg levels were detected in the Tennessee River, the former may affect the mainstem Mississippi River, whereas the latter probably do not. Sediment-associated concentrations of Ag, Cu, Pb, Zn, Cd, Cr, Co, Ba, Mo, Sb, Hg, and Fe are markedly elevated in the upper Columbia Basin, and appear to be detectable (Zn, Cd) as far downstream as the middle of the basin. These elevated concentrations seem to result from mining and/or mining-related activities. Consistently detectable concentrations of dissolved Se were found only in the Colorado River Basin. Calculated average annual suspended sediment fluxes at the mouths of the Mississippi and Rio Grande Basins were below, whereas those for the Columbia and Colorado Basins were above previously published annual values. Downstream suspended sediment-associated and total trace element fluxes
Quantum canonical ensemble: A projection operator approach
Magnus, Wim; Lemmens, Lucien; Brosens, Fons
2017-09-01
Knowing the exact number of particles N, and taking this knowledge into account, the quantum canonical ensemble imposes a constraint on the occupation number operators. The constraint particularly hampers the systematic calculation of the partition function and any relevant thermodynamic expectation value for arbitrary but fixed N. On the other hand, fixing only the average number of particles, one may remove the above constraint and simply factorize the traces in Fock space into traces over single-particle states. As is well known, that would be the strategy of the grand-canonical ensemble which, however, comes with an additional Lagrange multiplier to impose the average number of particles. The appearance of this multiplier can be avoided by invoking a projection operator that enables a constraint-free computation of the partition function and its derived quantities in the canonical ensemble, at the price of an angular or contour integration. Introduced in the recent past to handle various issues related to particle-number projected statistics, the projection operator approach proves beneficial to a wide variety of problems in condensed matter physics for which the canonical ensemble offers a natural and appropriate environment. In this light, we present a systematic treatment of the canonical ensemble that embeds the projection operator into the formalism of second quantization while explicitly fixing N, the very number of particles rather than the average. Being applicable to both bosonic and fermionic systems in arbitrary dimensions, transparent integral representations are provided for the partition function ZN and the Helmholtz free energy FN as well as for two- and four-point correlation functions. The chemical potential is not a Lagrange multiplier regulating the average particle number but can be extracted from FN+1 -FN, as illustrated for a two-dimensional fermion gas.
Pennington, D. D.; Garnica Chavira, L.; Villanueva-Rosales, N.
2017-12-01
People living in the vicinity of the middle Rio Grande from Elephant Butte Reservoir in New Mexico through Fort Quitman, Texas, including inhabitants on the Mexican side of the river, are confronted with numerous challenges that include drought, population growth, reduced surface water quality and quantity, declining aquifers, and expected future increases in temperature with more variable precipitation. The transboundary surface water is subject to complex regulation across two U.S. states and two nations (U.S. and Mexico). This presentation will summarize the modeling efforts of a USDA-funded project to characterize potential future solutions for water sustainability while managing agriculture, economic, and human impacts. It will present an online software system designed for rapid, flexible modeling of different climate, policy, and technology scenarios with stakeholders, and the underlying intelligent system that manages model selection, data and parameters, and user choices, and provides a provenance trace based on the W3C PROV standard.
Energy Technology Data Exchange (ETDEWEB)
Soares, Walace A.A., E-mail: walace@usp.br [Setor de Analises Toxicologicas. CETESB, Sao Paulo, SP (Brazil); Favaro, Deborah I.T., E-mail: defavaro@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Lab. de Analise por Ativacao com Neutrons
2011-07-01
The Salto Grande Reservoir is used for electric generation, irrigation, fish farming, recreation and water supply for the region's cities. The reservoir belongs to the city of Americana, located in on the eastern region of Sao Paulo State, Brazil. It belongs to the Piracicaba River Hydrographic Basin, the second most important economic and populated region and one of the most polluted areas in the State. This basin is located in a highly industrialized and agricultural region. Due to urban, industrial and agricultural activities as well as sewage wastes the water and sediments of this reservoir and surroundings are extremely contaminated, mainly by metals, according to CETESB (Environmental Control Agency of the Sao Paulo State). In order to obtain better information about its sediment contamination the present study reports results of the concentration of some major (Ca, Fe, K and Na), trace (As, Ba, Br, Co, Cr, Cs, Hf, Rb, Sb, Se, Ta, Th, U, Zn and rare earth (Ce, Eu, La, Lu, Nd, Sc, Sm, Tb and Yb)) elements in sediments and Cd, Cr, Cu, Ni and Pb concentration in sediments and water from the Salto Grande Reservoir. Multielementar analysis was carried out by Instrumental Neutron Activation Analysis (INAA). Multielemental concentrations in the sediment samples were compared to NASC (North American Shale Composite) values. The concentration values for metals As, Cd, Cr, Cu, Pb, Ni and Zn were compared to the Canadian Council of Minister of the Environment (CCME) oriented values (TEL and PEL) and adopted by CETESB, (author)
International Nuclear Information System (INIS)
Soares, Walace A.A.; Favaro, Deborah I.T.
2011-01-01
The Salto Grande Reservoir is used for electric generation, irrigation, fish farming, recreation and water supply for the region's cities. The reservoir belongs to the city of Americana, located in on the eastern region of Sao Paulo State, Brazil. It belongs to the Piracicaba River Hydrographic Basin, the second most important economic and populated region and one of the most polluted areas in the State. This basin is located in a highly industrialized and agricultural region. Due to urban, industrial and agricultural activities as well as sewage wastes the water and sediments of this reservoir and surroundings are extremely contaminated, mainly by metals, according to CETESB (Environmental Control Agency of the Sao Paulo State). In order to obtain better information about its sediment contamination the present study reports results of the concentration of some major (Ca, Fe, K and Na), trace (As, Ba, Br, Co, Cr, Cs, Hf, Rb, Sb, Se, Ta, Th, U, Zn and rare earth (Ce, Eu, La, Lu, Nd, Sc, Sm, Tb and Yb)) elements in sediments and Cd, Cr, Cu, Ni and Pb concentration in sediments and water from the Salto Grande Reservoir. Multielementar analysis was carried out by Instrumental Neutron Activation Analysis (INAA). Multielemental concentrations in the sediment samples were compared to NASC (North American Shale Composite) values. The concentration values for metals As, Cd, Cr, Cu, Pb, Ni and Zn were compared to the Canadian Council of Minister of the Environment (CCME) oriented values (TEL and PEL) and adopted by CETESB, (author)
International Nuclear Information System (INIS)
Franklin, Robson L.; Ferreira, Francisco J.; Favaro, Deborah I.T.; Bevilacqua, Jose Eduardo
2009-01-01
The Rio Grande Reservoir, Southeast of the Sao Paulo Metropolitan Area (SPMA) supplies water for four counties (Sao Bernardo do Campo, Sao Caetano do Sul, Santo Andre and Diadema). It has been seriously affected by urban expansion, due to chaotic urban occupation and improper use of the surrounding areas. In this study bottom sediment samples were collected, by using a Van Veen sampler, during the dry and rainy seasons. Four sampling points were defined by using GPS and are located at the mouth of the Rio Grande and Ribeirao Pires Rivers, in the middle of the reservoir and near the catchment point of the water supply. The sediment samples were submitted to instrumental neutron activation analysis (INAA) and the following elements were determined: As, Ba, Br, Co, Cr, Cs, Rb, Sb, Sc, Se, Ta, Th, U e Zn and the rare earth elements Ce, Eu, La, Lu, Nd, Sm, Tb, Yb. Short irradiation was also performed for total Hg determination by NAA using 197 Hg radioisotope. This was possible due to the high Hg concentration levels in these sediments. The methodology validation was carried out by certified reference material analyses. The results obtained for multielemental concentrations in the sediment samples were compared to NASC (North American Shale Composite) values. The concentration values obtained for As and metals Cr, Hg and Zn in the sediment samples were compared to the Canadian Council of Minister of the Environment (CCME) oriented values (TEL and PEL values) and adopted by CETESB. (author)
Derivation of Mayer Series from Canonical Ensemble
International Nuclear Information System (INIS)
Wang Xian-Zhi
2016-01-01
Mayer derived the Mayer series from both the canonical ensemble and the grand canonical ensemble by use of the cluster expansion method. In 2002, we conjectured a recursion formula of the canonical partition function of a fluid (X.Z. Wang, Phys. Rev. E 66 (2002) 056102). In this paper we give a proof for this formula by developing an appropriate expansion of the integrand of the canonical partition function. We further derive the Mayer series solely from the canonical ensemble by use of this recursion formula. (paper)
Derivation of Mayer Series from Canonical Ensemble
Wang, Xian-Zhi
2016-02-01
Mayer derived the Mayer series from both the canonical ensemble and the grand canonical ensemble by use of the cluster expansion method. In 2002, we conjectured a recursion formula of the canonical partition function of a fluid (X.Z. Wang, Phys. Rev. E 66 (2002) 056102). In this paper we give a proof for this formula by developing an appropriate expansion of the integrand of the canonical partition function. We further derive the Mayer series solely from the canonical ensemble by use of this recursion formula.
International Nuclear Information System (INIS)
Sun, Baichuan; Kayal, Sibnath; Chakraborty, Anutosh
2014-01-01
We have measured the methane uptakes on HKUST (Copper benzene-1,3,5-tricarboxylate, Cu-BTC MOF)-1 MOF (metal organic framework) for the temperatures ranging from 120 K to 300 K and pressures up to 10 bar. The experimentally measured HKUST-1 + CH 4 isotherms data are compared with uptakes of various adsorbents and methane systems. We have also simulated the methane uptakes and its density distribution on HKUST-1 employing GCMC (grand canonical Monte-carlo) simulation and compare with experimental data. In this article, we also present an extensive study on characterization and property evaluation of HKUST-1 MOF for CH 4 adsorption characteristics employing XRD (X-ray diffraction), SEM (scanning electron microscope) and TGA (thermo gravimetric analysis). Employing GCMC and the thermodynamic property fields of HKUST-1 + CH 4 system, the isosteric heat of adsorption (Q st ) is calculated and Q st is presented in a T-s (temperature-entropy) diagram. - Highlights: • Characterization of HKUST-1 MOFs by XRD, SEM, N 2 adsorption and TGA. • Measurement of CH 4 uptakes on HKUST-1 by volumetric methods. • GCMC simulation of methane uptakes and its density distribution on HKUST-1. • Isosteric heat of adsorption in a T-s (temperature-entropy) diagram
Romanticism, Sexuality, and the Canon.
Rowe, Kathleen K.
1990-01-01
Traces the Romanticism in the work and persona of film director Jean-Luc Godard. Examines the contradictions posed by Godard's politics and representations of sexuality. Asserts, that by bringing an ironic distance to the works of such canonized directors, viewers can take pleasure in those works despite their contradictions. (MM)
Trace and major elements in rock samples from Itingussu River Basin, Coroa-Grande, Rio de Janeiro
International Nuclear Information System (INIS)
Araripe, D.R.; Patchineelam, S.R.; Bellido, A.V.B.; Vasconcellos, M.B.A.
2006-01-01
The goal of the present work was to determine the concentration of 23 elements by instrumental neutron activation analysis in rock samples from the vicinity of Itingussu River, in order to investigate the contribution of trace and major elements from the local lithology to the river basin. The Itingussu River Basin ends in a mangrove area not yet largely impacted by antropogenic activities. So far, there are no data for the concentration of trace elements in that region, even though these data are important to the understanding of the influence of the rocks on the composition of the mangrove sediments. The results showed some enrichment of Th and some light rare earths, probably because of the presence of the mineral allanite and other accessory minerals, as identified by petrographic analysis. (author)
International Nuclear Information System (INIS)
Nelson, D.O.
1980-01-01
The Columbia River Basalt (CRB) group displays significant variations in major and trace element and Sr isotopic compositions. These compositions reflect complex and variable origins for the CRB magmas. Among the most varied is the Saddle Mountains Basalt (SMB) in which Sr ratios vary from 0.7078 to 0.7147 +- 0.002. The higher ratios reflect contamination through consistent correlations with major element compositions. Modeling suggests contamination by assimilation of 4.4 to 9.4 wt % of radiogenic crustal rocks. High delta 18 O values (up to +7.68 per mil) support the model. Age and field relations suggest that the contamination flowrocks are not the result of progressive contamination of a single magma, but rather reflect the contamination of independent magmas during this ascent
Canonical simulations with worldlines: An exploratory study in ϕ24 lattice field theory
Orasch, Oliver; Gattringer, Christof
2018-01-01
In this paper, we explore the perspectives for canonical simulations in the worldline formulation of a lattice field theory. Using the charged ϕ4 field in two dimensions as an example, we present the details of the canonical formulation based on worldlines and outline the algorithmic strategies for canonical worldline simulations. We discuss the steps for converting the data from the canonical approach to the grand canonical picture which we use for cross-checking our results. The canonical approach presented here can easily be generalized to other lattice field theories with a worldline representation.
Three dimensional canonical transformations
International Nuclear Information System (INIS)
Tegmen, A.
2010-01-01
A generic construction of canonical transformations is given in three-dimensional phase spaces on which Nambu bracket is imposed. First, the canonical transformations are defined as based on cannonade transformations. Second, it is shown that determination of the generating functions and the transformation itself for given generating function is possible by solving correspondent Pfaffian differential equations. Generating functions of type are introduced and all of them are listed. Infinitesimal canonical transformations are also discussed as the complementary subject. Finally, it is shown that decomposition of canonical transformations is also possible in three-dimensional phase spaces as in the usual two-dimensional ones.
Deviations from Wick's theorem in the canonical ensemble
Schönhammer, K.
2017-07-01
Wick's theorem for the expectation values of products of field operators for a system of noninteracting fermions or bosons plays an important role in the perturbative approach to the quantum many-body problem. A finite-temperature version holds in the framework of the grand canonical ensemble, but not for the canonical ensemble appropriate for systems with fixed particle number such as ultracold quantum gases in optical lattices. Here we present formulas for expectation values of products of field operators in the canonical ensemble using a method in the spirit of Gaudin's proof of Wick's theorem for the grand canonical case. The deviations from Wick's theorem are examined quantitatively for two simple models of noninteracting fermions.
Directory of Open Access Journals (Sweden)
Carlos García-Bedoya Maguiña
2011-05-01
Full Text Available Canon es un concepto clave en la historia literaria. En el presente artículo,se revisa la evolución histórica del canon literario peruano. Es solo con la llamada República Aristocrática, en las primeras décadas del siglo XX, que cabe hablar en el caso peruano de la formación de un auténtico canon nacional. El autor denomina a esta primera versión del canon literario peruano como canon oligárquico y destaca la importancia de la obra de Riva Agüero y de Ventura García Calderón en su configuración. Es solo más tarde, desde los años 20 y de modo definitivo desde los años 50, que puede hablarse de la emergencia de un nuevo canon literarioal que el autor propone determinar canon posoligárquico.
Canonical Information Analysis
DEFF Research Database (Denmark)
Vestergaard, Jacob Schack; Nielsen, Allan Aasbjerg
2015-01-01
is replaced by the information theoretical, entropy based measure mutual information, which is a much more general measure of association. We make canonical information analysis feasible for large sample problems, including for example multispectral images, due to the use of a fast kernel density estimator......Canonical correlation analysis is an established multivariate statistical method in which correlation between linear combinations of multivariate sets of variables is maximized. In canonical information analysis introduced here, linear correlation as a measure of association between variables...... for entropy estimation. Canonical information analysis is applied successfully to (1) simple simulated data to illustrate the basic idea and evaluate performance, (2) fusion of weather radar and optical geostationary satellite data in a situation with heavy precipitation, and (3) change detection in optical...
Classifying Linear Canonical Relations
Lorand, Jonathan
2015-01-01
In this Master's thesis, we consider the problem of classifying, up to conjugation by linear symplectomorphisms, linear canonical relations (lagrangian correspondences) from a finite-dimensional symplectic vector space to itself. We give an elementary introduction to the theory of linear canonical relations and present partial results toward the classification problem. This exposition should be accessible to undergraduate students with a basic familiarity with linear algebra.
Relations between canonical and non-canonical inflation
Energy Technology Data Exchange (ETDEWEB)
Gwyn, Rhiannon [Max-Planck-Institut fuer Gravitationsphysik (Albert-Einstein-Institut), Potsdam (Germany); Rummel, Markus [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Westphal, Alexander [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany). Theory Group
2012-12-15
We look for potential observational degeneracies between canonical and non-canonical models of inflation of a single field {phi}. Non-canonical inflationary models are characterized by higher than linear powers of the standard kinetic term X in the effective Lagrangian p(X,{phi}) and arise for instance in the context of the Dirac-Born-Infeld (DBI) action in string theory. An on-shell transformation is introduced that transforms non-canonical inflationary theories to theories with a canonical kinetic term. The 2-point function observables of the original non-canonical theory and its canonical transform are found to match in the case of DBI inflation.
Unified correspondence and canonicity
Zhao, Z.
2018-01-01
Correspondence theory originally arises as the study of the relation between modal formulas and first-order formulas interpreted over Kripke frames. We say that a modal formula and a first-order formula correspond to each other if they are valid on the same class of Kripke frames. Canonicity theory
Luo, Chongliang; Liu, Jin; Dey, Dipak K; Chen, Kun
2016-07-01
In many fields, multi-view datasets, measuring multiple distinct but interrelated sets of characteristics on the same set of subjects, together with data on certain outcomes or phenotypes, are routinely collected. The objective in such a problem is often two-fold: both to explore the association structures of multiple sets of measurements and to develop a parsimonious model for predicting the future outcomes. We study a unified canonical variate regression framework to tackle the two problems simultaneously. The proposed criterion integrates multiple canonical correlation analysis with predictive modeling, balancing between the association strength of the canonical variates and their joint predictive power on the outcomes. Moreover, the proposed criterion seeks multiple sets of canonical variates simultaneously to enable the examination of their joint effects on the outcomes, and is able to handle multivariate and non-Gaussian outcomes. An efficient algorithm based on variable splitting and Lagrangian multipliers is proposed. Simulation studies show the superior performance of the proposed approach. We demonstrate the effectiveness of the proposed approach in an [Formula: see text] intercross mice study and an alcohol dependence study. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Zhou, Chi-Chun; Dai, Wu-Sheng
2018-02-01
In statistical mechanics, for a system with a fixed number of particles, e.g. a finite-size system, strictly speaking, the thermodynamic quantity needs to be calculated in the canonical ensemble. Nevertheless, the calculation of the canonical partition function is difficult. In this paper, based on the mathematical theory of the symmetric function, we suggest a method for the calculation of the canonical partition function of ideal quantum gases, including ideal Bose, Fermi, and Gentile gases. Moreover, we express the canonical partition functions of interacting classical and quantum gases given by the classical and quantum cluster expansion methods in terms of the Bell polynomial in mathematics. The virial coefficients of ideal Bose, Fermi, and Gentile gases are calculated from the exact canonical partition function. The virial coefficients of interacting classical and quantum gases are calculated from the canonical partition function by using the expansion of the Bell polynomial, rather than calculated from the grand canonical potential.
Quaternion Linear Canonical Transform Application
Bahri, Mawardi
2015-01-01
Quaternion linear canonical transform (QLCT) is a generalization of the classical linear canonical transfom (LCT) using quaternion algebra. The focus of this paper is to introduce an application of the QLCT to study of generalized swept-frequency filter
Canonical transformations and generating functionals
Broer, L.J.F.; Kobussen, J.A.
1972-01-01
It is shown that canonical transformations for field variables in hamiltonian partial differential equations can be obtained from generating functionals in the same way as classical canonical transformations from generating functions. A simple proof of the relation between infinitesimal invariant
Canonical transformations of Kepler trajectories
International Nuclear Information System (INIS)
Mostowski, Jan
2010-01-01
In this paper, canonical transformations generated by constants of motion in the case of the Kepler problem are discussed. It is shown that canonical transformations generated by angular momentum are rotations of the trajectory. Particular attention is paid to canonical transformations generated by the Runge-Lenz vector. It is shown that these transformations change the eccentricity of the orbit. A method of obtaining elliptic trajectories from the circular ones with the help of canonical trajectories is discussed.
Extension of Kirkwood-Buff theory to the canonical ensemble
Rogers, David M.
2018-02-01
Kirkwood-Buff (KB) integrals are notoriously difficult to converge from a canonical simulation because they require estimating the grand-canonical radial distribution. The same essential difficulty is encountered when attempting to estimate the direct correlation function of Ornstein-Zernike theory by inverting the pair correlation functions. We present a new theory that applies to the entire, finite, simulation volume, so that no cutoff issues arise at all. The theory gives the direct correlation function for closed systems, while smoothness of the direct correlation function in reciprocal space allows calculating canonical KB integrals via a well-posed extrapolation to the origin. The present analysis method represents an improvement over previous work because it makes use of the entire simulation volume and its convergence can be accelerated using known properties of the direct correlation function. Using known interaction energy functions can make this extrapolation near perfect accuracy in the low-density case. Because finite size effects are stronger in the canonical than in the grand-canonical ensemble, we state ensemble correction formulas for the chemical potential and the KB coefficients. The new theory is illustrated with both analytical and simulation results on the 1D Ising model and a supercritical Lennard-Jones fluid. For the latter, the finite-size corrections are shown to be small.
Whose Canon? Culturalization versus Democratization
Directory of Open Access Journals (Sweden)
Erling Bjurström
2012-06-01
Full Text Available Current accounts – and particularly the critique – of canon formation are primarily based on some form of identity politics. In the 20th century a representational model of social identities replaced cultivation as the primary means to democratize the canons of the fine arts. In a parallel development, the discourse on canons has shifted its focus from processes of inclusion to those of exclusion. This shift corresponds, on the one hand, to the construction of so-called alternative canons or counter-canons, and, on the other hand, to attempts to restore the authority of canons considered to be in a state of crisis or decaying. Regardless of the democratic stance of these efforts, the construction of alternatives or the reestablishment of decaying canons does not seem to achieve their aims, since they break with the explicit and implicit rules of canon formation. Politically motivated attempts to revise or restore a specific canon make the workings of canon formation too visible, transparent and calculated, thereby breaking the spell of its imaginary character. Retracing the history of the canonization of the fine arts reveals that it was originally tied to the disembedding of artists and artworks from social and worldly affairs, whereas debates about canons of the fine arts since the end of the 20th century are heavily dependent on their social, cultural and historical reembedding. The latter has the character of disenchantment, but has also fettered the canon debate in notions of “our” versus “their” culture. However, by emphasizing the dedifferentiation of contemporary processes of culturalization, the advancing canonization of popular culture seems to be able to break with identity politics that foster notions of “our” culture in the present thinking on canons, and push it in a more transgressive, syncretic or hybrid direction.
Energy Technology Data Exchange (ETDEWEB)
Wasserman, Julio Cesar [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Dept. de Geoquimica; Figueiredo, Ana Maria G. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil); Figueira, Andre Luiz [Universidade do Estado, Rio de Janeiro, RJ (Brazil). Dept. de Oceanografia; Kelecom, Alphonse [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Dept. de Biologia Geral
2002-07-01
The present work aims to identify atmospheric and marine inputs of 9 metals (Ba, Co, Cr, Cs, Fe, Hf, Rb, Sc, Zn), 8 rare earths (La, Ce, Nd, Sm, Eu, Tb, Yb e Lu), 2 actinides (U, Th) and 3 non-metals (As, Sb, Se) in sediment cores from a remote area, the Biological Reserve of Praia do Sul, Ilha Grande, Rio de Janeiro, Brazil. The sediment cores were sampled in a peat bog (out of the tidal reach) and in a mangrove, downstream of the peat bog. The analytical technique employed was Instrumental Neutron Activation Analysis. The samples were irradiated for 16 hours at a thermal neutron flux of 10{sup 12} n cm{sup -2} s{sup -1} at the IEA-R1 reactor of IPEN. The measurements of the induced gamma-ray activity were carried out by high resolution gamma spectrometry, with an hyperpure Ge detector. A preliminary sediment dating with Po-210 was also carried out by applying radiochemical procedures and measurements were done in an Alfa spectrometer The results indicate that the peat bog core present a slight surface enrichment that can be attributed to atmospheric inputs. Increasing concentrations of metals with age is probably due to history of soil occupation. In the mangrove core, no significant increase in concentration could be detected in the surface sediments (except for Zn) confirming the suitability of the peat bog core as a tracer for atmospheric inputs. (author)
International Nuclear Information System (INIS)
Wasserman, Julio Cesar; Figueira, Andre Luiz; Kelecom, Alphonse
2002-01-01
The present work aims to identify atmospheric and marine inputs of 9 metals (Ba, Co, Cr, Cs, Fe, Hf, Rb, Sc, Zn), 8 rare earths (La, Ce, Nd, Sm, Eu, Tb, Yb e Lu), 2 actinides (U, Th) and 3 non-metals (As, Sb, Se) in sediment cores from a remote area, the Biological Reserve of Praia do Sul, Ilha Grande, Rio de Janeiro, Brazil. The sediment cores were sampled in a peat bog (out of the tidal reach) and in a mangrove, downstream of the peat bog. The analytical technique employed was Instrumental Neutron Activation Analysis. The samples were irradiated for 16 hours at a thermal neutron flux of 10 12 n cm -2 s -1 at the IEA-R1 reactor of IPEN. The measurements of the induced gamma-ray activity were carried out by high resolution gamma spectrometry, with an hyperpure Ge detector. A preliminary sediment dating with Po-210 was also carried out by applying radiochemical procedures and measurements were done in an Alfa spectrometer The results indicate that the peat bog core present a slight surface enrichment that can be attributed to atmospheric inputs. Increasing concentrations of metals with age is probably due to history of soil occupation. In the mangrove core, no significant increase in concentration could be detected in the surface sediments (except for Zn) confirming the suitability of the peat bog core as a tracer for atmospheric inputs. (author)
International Nuclear Information System (INIS)
Correa da Silva, Z.C.; Piccoli, A.E.M.
1985-01-01
The trace elements Zr, Y, Sr, U, Rb, Th, Ga, Pb, Zn, Cu, Ni, Co, Cr, Ce, Ba and La were determined by X-Ray fluorescence spectroscopy on samples from shales, carbonaceous shales, coal and fine-grained groundmass of a paraconglomerate ( pedra-areia ) colleted from the Papaleo and Faxinal outcrops and from the Faxinal Coal Mine, Guaiba, RS. The analysis pointed out an association of zirconium, copper, uranium and thorium with coal and carbonaceous rocks, whereas barium and galium are related to inorganic rocks. The other elements showed neither preferential relationships with organic nor inorganic matter. The extremely high contents of uranium, cerium and lanthanum in the upper coal layers in both Papaleo and Faxinal outcrops suggest an association with the top of the Rio Bonito Formation in this area. (Author) [pt
The canon as text for a biblical theology
Directory of Open Access Journals (Sweden)
James A. Loader
2005-10-01
Full Text Available The novelty of the canonical approach is questioned and its fascination at least partly traced to the Reformation, as well as to the post-Reformation’s need for a clear and authoritative canon to perform the function previously performed by the church. This does not minimise the elusiveness and deeply contradictory positions both within the canon and triggered by it. On the one hand, the canon itself is a centripetal phenomenon and does play an important role in exegesis and theology. Even so, on the other hand, it not only contains many difficulties, but also causes various additional problems of a formal as well as a theological nature. The question is mooted whether the canonical approach alleviates or aggravates the dilemma. Since this approach has become a major factor in Christian theology, aspects of the Christian canon are used to gauge whether “canon” is an appropriate category for eliminating difficulties that arise by virtue of its own existence. Problematic uses and appropriations of several Old Testament canons are advanced, as well as evidence in the New Testament of a consciousness that the “old” has been surpassed(“Überbietungsbewußtsein”. It is maintained that at least the Childs version of the canonical approach fails to smooth out these and similar difficulties. As a method it can cater for the New Testament’s (superior role as the hermeneutical standard for evaluating the Old, but flounders on its inability to create the theological unity it claims can solve religious problems exposed by Old Testament historical criticism. It is concluded that canon as a category cannot be dispensed with, but is useful for the opposite of the purpose to which it is conventionally put: far from bringing about theological “unity” or producing a standard for “correct” exegesis, it requires different readings of different canons.
Hinck, Jo Ellen; Cleveland, Danielle; Brumbaugh, William G; Linder, Greg; Lankton, Julia
2017-02-01
The risks to wildlife and humans from uranium (U) mining in the Grand Canyon watershed are largely unknown. In addition to U, other co-occurring ore constituents contribute to risks to biological receptors depending on their toxicological profiles. This study characterizes the pre-mining concentrations of total arsenic (As), cadmium (Cd), copper (Cu), lead (Pb), mercury (Hg), nickel (Ni), selenium (Se), thallium (Tl), U, and zinc (Zn); radiation levels; and histopathology in biota (vegetation, invertebrates, amphibians, birds, and mammals) at the Canyon Mine. Gross alpha levels were below the reporting limit (4 pCi/g) in all samples, and gross beta levels were indicative of background in vegetation (<10-17 pCi/g) and rodents (<10-43.5 pCi/g). Concentrations of U, Tl, Pb, Ni, Cu, and As in vegetation downwind from the mine were likely the result of aeolian transport. Chemical concentrations in rodents and terrestrial invertebrates indicate that surface disturbance during mine construction has not resulted in statistically significant spatial differences in fauna concentrations adjacent to the mine. Chemical concentrations in egg contents and nestlings of non-aquatic birds were less than method quantification limits or did not exceed toxicity thresholds. Bioaccumulation of As, Pb, Se, Tl, and U was evident in Western spadefoot (Spea multiplicata) tadpoles from the mine containment pond; concentrations of As (28.9-31.4 μg/g) and Se (5.81-7.20 μg/g) exceeded toxicity values and were significantly greater than in tadpoles from a nearby water source. Continued evaluation of As and Se in biota inhabiting and forging in the mine containment pond is warranted as mining progresses.
Directory of Open Access Journals (Sweden)
Editorial, Equipo
1961-07-01
Full Text Available El empleo creciente del material pesado auxiliar en la construcción de obras de ingeniería civil ha motivado la fabricación de grandes plataformas, capaces de transportar toda clase de maquinaria auxiliar. En general, este tipo de maquinaria requiere medios de transporte, pues su circulación por carreteras es lenta, obstructiva y cara, siempre que se trate de grandes distancias, caso presente en la mayoría de ocasiones en que se exige un traslado de esta maquinaria de una a otra obra.
Restoring canonical partition functions from imaginary chemical potential
Bornyakov, V. G.; Boyda, D.; Goy, V.; Molochkov, A.; Nakamura, A.; Nikolaev, A.; Zakharov, V. I.
2018-03-01
Using GPGPU techniques and multi-precision calculation we developed the code to study QCD phase transition line in the canonical approach. The canonical approach is a powerful tool to investigate sign problem in Lattice QCD. The central part of the canonical approach is the fugacity expansion of the grand canonical partition functions. Canonical partition functions Zn(T) are coefficients of this expansion. Using various methods we study properties of Zn(T). At the last step we perform cubic spline for temperature dependence of Zn(T) at fixed n and compute baryon number susceptibility χB/T2 as function of temperature. After that we compute numerically ∂χ/∂T and restore crossover line in QCD phase diagram. We use improved Wilson fermions and Iwasaki gauge action on the 163 × 4 lattice with mπ/mρ = 0.8 as a sandbox to check the canonical approach. In this framework we obtain coefficient in parametrization of crossover line Tc(µ2B) = Tc(C-ĸµ2B/T2c) with ĸ = -0.0453 ± 0.0099.
Generalized Canonical Time Warping.
Zhou, Feng; De la Torre, Fernando
2016-02-01
Temporal alignment of human motion has been of recent interest due to its applications in animation, tele-rehabilitation and activity recognition. This paper presents generalized canonical time warping (GCTW), an extension of dynamic time warping (DTW) and canonical correlation analysis (CCA) for temporally aligning multi-modal sequences from multiple subjects performing similar activities. GCTW extends previous work on DTW and CCA in several ways: (1) it combines CCA with DTW to align multi-modal data (e.g., video and motion capture data); (2) it extends DTW by using a linear combination of monotonic functions to represent the warping path, providing a more flexible temporal warp. Unlike exact DTW, which has quadratic complexity, we propose a linear time algorithm to minimize GCTW. (3) GCTW allows simultaneous alignment of multiple sequences. Experimental results on aligning multi-modal data, facial expressions, motion capture data and video illustrate the benefits of GCTW. The code is available at http://humansensing.cs.cmu.edu/ctw.
IUS CONNUBII: Canonical Dimension
Directory of Open Access Journals (Sweden)
Silma Mendes Berti
2018-03-01
Full Text Available anon Law, in regulating under Can.1058 the "ius connubii", lays down that: "All those who are not prohibited from doing so by law may contract matrimony." This disposition, although apparently simple, has a wide and deep range of implications, questionings and possibilities for investigation, especially as it involves an extremely delicate relationship. A perfect combination of law and sacrament, the "ius connubii", in its close relationship with the constitution of the family, which is the sanctuary of Love, is an important problem, which faces the legislator, both in the legislation of the State, specifically in Civil Law, and in that of the Church. As the general principle of the canonical matrimonial system, "ius connubii' is the source of interpretation of all rules concerning matrimony, especially when it comes to the distinction between sacramental reality and liturgical ceremony. This is the fact, which is the basis of our reflections.
Directory of Open Access Journals (Sweden)
García de Castro, Emilio
1957-11-01
Full Text Available Se describen en este artículo una serie de aparatos para grandes cocinas, vistos por los autores durante un rápido viaje por Alemania. Aprovechando los datos obtenidos se analizan brevemente las necesidades de una gran cocina moderna, comentando los planos de las instalaciones en varios hoteles o instituciones de todo el mundo. La mayoría de la información.
Directory of Open Access Journals (Sweden)
Luiz Carlos Santos Porto
2009-12-01
Full Text Available Metais pesados, também denominados elementos traço, podem ser essenciais ao metabolismo de organismos vivos, e, ao mesmo tempo, dependendo de suas concentrações, altamente tóxicos. Com o objetivo de investigar a toxicidade da água da Bacia dos Rios Butuí-Icamaquã, na fronteira oeste do Rio Grande do Sul, foram analisados, através de espectrofotômetro de absorção atômica, os teores de alumínio, cádmio, chumbo, cobre, cromo, manganês, níquel e zinco em vísceras abdominais de peixes, coletados, entre junho de 2007 e fevereiro de 2008, em pontos determinados nos rios Butuí, Icamaquã e Uruguai. Mostraram-se acima do nível considerado seguro para consumo humano: alumínio, cádmio, manganês e níquel e teores próximos aos limites legais foram encontrados para cobre e cromo. A análise simultânea de amostras da água coletadas nos mesmos locais acusou em espectrofotômetro de luz visível, níveis superiores aos limites legais de bromo, chumbo, cianeto, cobre, cromato, fenóis, fosfato, manganês e sulfeto. Estes elementos, em tais concentrações na água e nos peixes, podem comprometer o ecossistema ou representar riscos à saúde humana.Heavy metals, also called trace elements, may be essential to the metabolism of living organisms, and at the same time, depending on their concentrations, highly toxic. With the objective to investigate the toxicity of water of the Butuí-Icamaquã Rivers Basin on the border west of Rio Grande do Sul, were analyzed by atomic absorption spectrophotometer, the contents of aluminum, cadmium, chromium, copper, lead, manganese, nickel and zinc in abdominal viscera of fish, collected between June 2007 and February 2008, at selected points in Butuí, Icamaquã and Uruguai rivers. Aluminum, cadmium, manganese and nickel were above the levels considered safe for human consumption and levels near the legal limit were found for chrome and copper. The simultaneous analysis of water samples collected in
Canonical Labelling of Site Graphs
Directory of Open Access Journals (Sweden)
Nicolas Oury
2013-06-01
Full Text Available We investigate algorithms for canonical labelling of site graphs, i.e. graphs in which edges bind vertices on sites with locally unique names. We first show that the problem of canonical labelling of site graphs reduces to the problem of canonical labelling of graphs with edge colourings. We then present two canonical labelling algorithms based on edge enumeration, and a third based on an extension of Hopcroft's partition refinement algorithm. All run in quadratic worst case time individually. However, one of the edge enumeration algorithms runs in sub-quadratic time for graphs with "many" automorphisms, and the partition refinement algorithm runs in sub-quadratic time for graphs with "few" bisimulation equivalences. This suite of algorithms was chosen based on the expectation that graphs fall in one of those two categories. If that is the case, a combined algorithm runs in sub-quadratic worst case time. Whether this expectation is reasonable remains an interesting open problem.
Backlund transformations as canonical transformations
International Nuclear Information System (INIS)
Villani, A.; Zimerman, A.H.
1977-01-01
Toda and Wadati as well as Kodama and Wadati have shown that the Backlund transformations, for the exponential lattice equation, sine-Gordon equation, K-dV (Korteweg de Vries) equation and modifies K-dV equation, are canonical transformation. It is shown that the Backlund transformation for the Boussinesq equation, for a generalized K-dV equation, for a model equation for shallow water waves and for the nonlinear Schroedinger equation are also canonical transformations [pt
Canonical formulation of general-relativistic theories
International Nuclear Information System (INIS)
Bergmann, P.G.
1987-01-01
With the birth of quantum field theory in the late twenties physicists decided that nature could not be half classical and half quantum, and that the gravitational field ought to be quanticized, just as the electromagnetic field had been. One could accept the group of differomorphisms as a fundamental characteristic of general relativity (and indeed of all general-relativistic theories), and proceed to construct a quantum field-theory that was adapted to that group. Quantization would be attempted by way of a Hamiltonian formulation of the (classical) theory, and quantum commutation relations be patterned after the Poisson brackets arising in that formulation. This program is usually called the canonical quantization program, whereas the weak-field approach is known as covariant quantization. The first steps, conceived entirely within the framework of the classical theory, turned out to be beset with technical and conceptual difficulties, which today are essentially resolved. In this paper the author traces out these initial steps
Canonical quantum gravity and consistent discretizations
Indian Academy of Sciences (India)
Abstract. This paper covers some developments in canonical quantum gravity that ... derstanding the real Ashtekar variables four dimensionally [4], or the recent work ... Traditionally, canonical formulations of general relativity considered as canonical variables the metric on a spatial slice qab and a canonically conjugate.
Universal critical wrapping probabilities in the canonical ensemble
Directory of Open Access Journals (Sweden)
Hao Hu
2015-09-01
Full Text Available Universal dimensionless quantities, such as Binder ratios and wrapping probabilities, play an important role in the study of critical phenomena. We study the finite-size scaling behavior of the wrapping probability for the Potts model in the random-cluster representation, under the constraint that the total number of occupied bonds is fixed, so that the canonical ensemble applies. We derive that, in the limit L→∞, the critical values of the wrapping probability are different from those of the unconstrained model, i.e. the model in the grand-canonical ensemble, but still universal, for systems with 2yt−d>0 where yt=1/ν is the thermal renormalization exponent and d is the spatial dimension. Similar modifications apply to other dimensionless quantities, such as Binder ratios. For systems with 2yt−d≤0, these quantities share same critical universal values in the two ensembles. It is also derived that new finite-size corrections are induced. These findings apply more generally to systems in the canonical ensemble, e.g. the dilute Potts model with a fixed total number of vacancies. Finally, we formulate an efficient cluster-type algorithm for the canonical ensemble, and confirm these predictions by extensive simulations.
Quantum correlations of ideal Bose and Fermi gases in the canonical ensemble
International Nuclear Information System (INIS)
Tsutsui, Kazumasa; Kita, Takafumi
2016-01-01
We derive an expression for the reduced density matrices of ideal Bose and Fermi gases in the canonical ensemble, which corresponds to the Bloch-De Dominicis (or Wick's) theorem in the grand canonical ensemble for normal-ordered products of operators. Using this expression, we study one- and two-body correlations of homogeneous ideal gases with N particles. The pair distribution function g (2) (r) of fermions clearly exhibits antibunching with g (2) (0) = 0 due to the Pauli exclusion principle at all temperatures, whereas that of normal bosons shows bunching with g (2) (0) ≈ 2, corresponding to the Hanbury Brown-Twiss effect. For bosons below the Bose-Einstein condensation temperature T 0 , an off-diagonal long-range order develops in the one-particle density matrix to reach g (1) (r) = 1 at T = 0, and the pair correlation starts to decrease towards g (2) (r) ≈ 1 at T = 0. The results for N → ∞ are seen to converge to those of the grand canonical ensemble obtained by assuming the average <ψ(r)> of the field operator ψ(r) below T 0 . This fact justifies the introduction of the 'anomalous' average <ψ(r)> ≠ 0 below T 0 in the grand canonical ensemble as a mathematical means of removing unphysical particle-number fluctuations to reproduce the canonical results in the thermodynamic limit. (author)
Periodicity, the Canon and Sport
Directory of Open Access Journals (Sweden)
Thomas F. Scanlon
2015-10-01
Full Text Available The topic according to this title is admittedly a broad one, embracing two very general concepts of time and of the cultural valuation of artistic products. Both phenomena are, in the present view, largely constructed by their contemporary cultures, and given authority to a great extent from the prestige of the past. The antiquity of tradition brings with it a certain cachet. Even though there may be peripheral debates in any given society which question the specifics of periodization or canonicity, individuals generally accept the consensus designation of a sequence of historical periods and they accept a list of highly valued artistic works as canonical or authoritative. We will first examine some of the processes of periodization and of canon-formation, after which we will discuss some specific examples of how these processes have worked in the sport of two ancient cultures, namely Greece and Mesoamerica.
Canonical Authors in Consumption Theory
DEFF Research Database (Denmark)
Canonical Authors in Consumption Theory is the first work to compile the contributions of the greatest social thinkers in the global conversation about consumption and consumer culture. A prestigious reference work, it offers original chapters by the world's most prominent thought leaders and sur...
CANONICAL BACKWARD DIFFERENTIATION SCHEMES FOR ...
African Journals Online (AJOL)
This paper describes a new nonlinear backward differentiation schemes for the numerical solution of nonlinear initial value problems of first order ordinary differential equations. The schemes are based on rational interpolation obtained from canonical polynomials. They are A-stable. The test problems show that they give ...
Realizations of the canonical representation
Indian Academy of Sciences (India)
Traditionally, the canonical representation is realized on the Hilbert space ... Fix a decomposition R2n = Rn × Rn ..... to an orthonormal basis {ψ1,ψ2,. ..... [7] Vemuri M K, A non-commutative Sobolev inequality and its application to spectral.
Constructing canonical bases of quantized enveloping algebras
Graaf, W.A. de
2001-01-01
An algorithm for computing the elements of a given weight of the canonical basis of a quantized enveloping algebra is described. Subsequently, a similar algorithm is presented for computing the canonical basis of a finite-dimensional module.
Generalized canonical correlation analysis with missing values
M. van de Velden (Michel); Y. Takane
2012-01-01
textabstractGeneralized canonical correlation analysis is a versatile technique that allows the joint analysis of several sets of data matrices. The generalized canonical correlation analysis solution can be obtained through an eigenequation and distributional assumptions are not required. When
Titchmarsh-Weyl theory for canonical systems
Directory of Open Access Journals (Sweden)
Keshav Raj Acharya
2014-11-01
Full Text Available The main purpose of this paper is to develop Titchmarsh- Weyl theory of canonical systems. To this end, we first observe the fact that Schrodinger and Jacobi equations can be written into canonical systems. We then discuss the theory of Weyl m-function for canonical systems and establish the relation between the Weyl m-functions of Schrodinger equations and that of canonical systems which involve Schrodinger equations.
Modern canonical quantum general relativity
Thiemann, Thomas
2007-01-01
This is an introduction to the by now fifteen years old research field of canonical quantum general relativity, sometimes called "loop quantum gravity". The term "modern" in the title refers to the fact that the quantum theory is based on formulating classical general relativity as a theory of connections rather than metrics as compared to in original version due to Arnowitt, Deser and Misner. Canonical quantum general relativity is an attempt to define a mathematically rigorous, non-perturbative, background independent theory of Lorentzian quantum gravity in four spacetime dimensions in the continuum. The approach is minimal in that one simply analyzes the logical consequences of combining the principles of general relativity with the principles of quantum mechanics. The requirement to preserve background independence has lead to new, fascinating mathematical structures which one does not see in perturbative approaches, e.g. a fundamental discreteness of spacetime seems to be a prediction of the theory provi...
Functional Multiple-Set Canonical Correlation Analysis
Hwang, Heungsun; Jung, Kwanghee; Takane, Yoshio; Woodward, Todd S.
2012-01-01
We propose functional multiple-set canonical correlation analysis for exploring associations among multiple sets of functions. The proposed method includes functional canonical correlation analysis as a special case when only two sets of functions are considered. As in classical multiple-set canonical correlation analysis, computationally, the…
Modern Canonical Quantum General Relativity
Thiemann, Thomas
2008-11-01
Preface; Notation and conventions; Introduction; Part I. Classical Foundations, Interpretation and the Canonical Quantisation Programme: 1. Classical Hamiltonian formulation of general relativity; 2. The problem of time, locality and the interpretation of quantum mechanics; 3. The programme of canonical quantisation; 4. The new canonical variables of Ashtekar for general relativity; Part II. Foundations of Modern Canonical Quantum General Relativity: 5. Introduction; 6. Step I: the holonomy-flux algebra [P]; 7. Step II: quantum-algebra; 8. Step III: representation theory of [A]; 9. Step IV: 1. Implementation and solution of the kinematical constraints; 10. Step V: 2. Implementation and solution of the Hamiltonian constraint; 11. Step VI: semiclassical analysis; Part III. Physical Applications: 12. Extension to standard matter; 13. Kinematical geometrical operators; 14. Spin foam models; 15. Quantum black hole physics; 16. Applications to particle physics and quantum cosmology; 17. Loop quantum gravity phenomenology; Part IV. Mathematical Tools and their Connection to Physics: 18. Tools from general topology; 19. Differential, Riemannian, symplectic and complex geometry; 20. Semianalytical category; 21. Elements of fibre bundle theory; 22. Holonomies on non-trivial fibre bundles; 23. Geometric quantisation; 24. The Dirac algorithm for field theories with constraints; 25. Tools from measure theory; 26. Elementary introduction to Gel'fand theory for Abelean C* algebras; 27. Bohr compactification of the real line; 28. Operatir -algebras and spectral theorem; 29. Refined algebraic quantisation (RAQ) and direct integral decomposition (DID); 30. Basics of harmonic analysis on compact Lie groups; 31. Spin network functions for SU(2); 32. + Functional analytical description of classical connection dynamics; Bibliography; Index.
Extending canonical Monte Carlo methods
International Nuclear Information System (INIS)
Velazquez, L; Curilef, S
2010-01-01
In this paper, we discuss the implications of a recently obtained equilibrium fluctuation-dissipation relation for the extension of the available Monte Carlo methods on the basis of the consideration of the Gibbs canonical ensemble to account for the existence of an anomalous regime with negative heat capacities C α with α≈0.2 for the particular case of the 2D ten-state Potts model
Canonical formalism for relativistic dynamics
International Nuclear Information System (INIS)
Penafiel-Nava, V.M.
1982-01-01
The possibility of a canonical formalism appropriate for a dynamical theory of isolated relativistic multiparticle systems involving scalar interactions is studied. It is shown that a single time-parameter structure satisfying the requirements of Poincare invariance and simultaneity of the constituents (global tranversality) can not be derived from a homogeneous Lagrangian. The dynamics is deduced initially from a non-homogeneous but singular Lagrangian designed to accommodate the global tranversality constraints with the equaltime plane associated to the total momentum of the system. An equivalent standard Lagrangian is used to generalize the parametrization procedure which is referred to an arbitrary geodesic in Minkowski space. The equations of motion and the definition of center of momentum are invariant with respect to the choice of geodesic and the entire formalism becomes separable. In the original 8N-dimensional phase-space, the symmetries of the Lagrangian give rise to a canonical realization of a fifteen-generator Lie algebra which is projected in the 6N dimensional hypersurface of dynamical motions. The time-component of the total momentum is thus reduced to a neutral element and the canonical Hamiltonian survives as the only generator for time-translations so that the no-interaction theorem becomes inapplicable
Canonical trivialization of gravitational gradients
International Nuclear Information System (INIS)
Niedermaier, Max
2017-01-01
A one-parameter family of canonical transformations is constructed that reduces the Hamiltonian form of the Einstein–Hilbert action to its strong coupling limit where dynamical spatial gradients are absent. The parameter can alternatively be viewed as the overall scale of the spatial metric or as a fractional inverse power of Newton’s constant. The generating function of the canonical transformation is constructed iteratively as a powerseries in the parameter to all orders. The algorithm draws on Lie–Deprit transformation theory and defines a ‘trivialization map’ with several bonus properties: (i) Trivialization of the Hamiltonian constraint implies that of the action while the diffeomorphism constraint is automatically co-transformed. (ii) Only a set of ordinary differential equations needs to be solved to drive the iteration via a homological equation where no gauge fixing is required. (iii) In contrast to (the classical limit of) a Lagrangian trivialization map the algorithm also produces series solutions of the field equations. (iv) In the strong coupling theory temporal gauge variations are abelian, nevertheless the map intertwines with the respective gauge symmetries on the action, the field equations, and their solutions. (paper)
Canonical trivialization of gravitational gradients
Niedermaier, Max
2017-06-01
A one-parameter family of canonical transformations is constructed that reduces the Hamiltonian form of the Einstein-Hilbert action to its strong coupling limit where dynamical spatial gradients are absent. The parameter can alternatively be viewed as the overall scale of the spatial metric or as a fractional inverse power of Newton’s constant. The generating function of the canonical transformation is constructed iteratively as a powerseries in the parameter to all orders. The algorithm draws on Lie-Deprit transformation theory and defines a ‘trivialization map’ with several bonus properties: (i) Trivialization of the Hamiltonian constraint implies that of the action while the diffeomorphism constraint is automatically co-transformed. (ii) Only a set of ordinary differential equations needs to be solved to drive the iteration via a homological equation where no gauge fixing is required. (iii) In contrast to (the classical limit of) a Lagrangian trivialization map the algorithm also produces series solutions of the field equations. (iv) In the strong coupling theory temporal gauge variations are abelian, nevertheless the map intertwines with the respective gauge symmetries on the action, the field equations, and their solutions.
Canonical ensembles and nonzero density quantum chromodynamics
International Nuclear Information System (INIS)
Hasenfratz, A.; Toussaint, D.
1992-01-01
We study QCD with nonzero chemical potential on 4 4 lattices by averaging over the canonical partition functions, or sectors with fixed quark number. We derive a condensed matrix of size 2x3xL 3 whose eigenvalues can be used to find the canonical partition functions. We also experiment with a weight for configuration generation which respects the Z(3) symmetry which forces the canonical partition function to be zero for quark numbers that are not multiples of three. (orig.)
Robust canonical correlations: A comparative study
Branco, JA; Croux, Christophe; Filzmoser, P; Oliveira, MR
2005-01-01
Several approaches for robust canonical correlation analysis will be presented and discussed. A first method is based on the definition of canonical correlation analysis as looking for linear combinations of two sets of variables having maximal (robust) correlation. A second method is based on alternating robust regressions. These methods axe discussed in detail and compared with the more traditional approach to robust canonical correlation via covariance matrix estimates. A simulation study ...
Stabilizing canonical-ensemble calculations in the auxiliary-field Monte Carlo method
Gilbreth, C. N.; Alhassid, Y.
2015-03-01
Quantum Monte Carlo methods are powerful techniques for studying strongly interacting Fermi systems. However, implementing these methods on computers with finite-precision arithmetic requires careful attention to numerical stability. In the auxiliary-field Monte Carlo (AFMC) method, low-temperature or large-model-space calculations require numerically stabilized matrix multiplication. When adapting methods used in the grand-canonical ensemble to the canonical ensemble of fixed particle number, the numerical stabilization increases the number of required floating-point operations for computing observables by a factor of the size of the single-particle model space, and thus can greatly limit the systems that can be studied. We describe an improved method for stabilizing canonical-ensemble calculations in AFMC that exhibits better scaling, and present numerical tests that demonstrate the accuracy and improved performance of the method.
Log canonical thresholds of smooth Fano threefolds
International Nuclear Information System (INIS)
Cheltsov, Ivan A; Shramov, Konstantin A
2008-01-01
The complex singularity exponent is a local invariant of a holomorphic function determined by the integrability of fractional powers of the function. The log canonical thresholds of effective Q-divisors on normal algebraic varieties are algebraic counterparts of complex singularity exponents. For a Fano variety, these invariants have global analogues. In the former case, it is the so-called α-invariant of Tian; in the latter case, it is the global log canonical threshold of the Fano variety, which is the infimum of log canonical thresholds of all effective Q-divisors numerically equivalent to the anticanonical divisor. An appendix to this paper contains a proof that the global log canonical threshold of a smooth Fano variety coincides with its α-invariant of Tian. The purpose of the paper is to compute the global log canonical thresholds of smooth Fano threefolds (altogether, there are 105 deformation families of such threefolds). The global log canonical thresholds are computed for every smooth threefold in 64 deformation families, and the global log canonical thresholds are computed for a general threefold in 20 deformation families. Some bounds for the global log canonical thresholds are computed for 14 deformation families. Appendix A is due to J.-P. Demailly.
The Current Canon in British Romantics Studies.
Linkin, Harriet Kramer
1991-01-01
Describes and reports on a survey of 164 U.S. universities to ascertain what is taught as the current canon of British Romantic literature. Asserts that the canon may now include Mary Shelley with the former standard six major male Romantic poets, indicating a significant emergence of a feminist perspective on British Romanticism in the classroom.…
Moving Targets: Constructing Canons, 2013–2014
Hirsch, BD
2015-01-01
This review essay considers early modern dramatic authorship and canons in the context of two recent publications: an anthology of plays -- William Shakespeare and Others: Collaborative Plays (2013), edited by Jonathan Bate and Eric Rasmussen as a companion volume to the RSC Complete Works -- and a monograph study -- Jeremy Lopez's Constructing the Canon of Early Modern Drama (2014).
Modern Canonical Quantum General Relativity;
International Nuclear Information System (INIS)
Kiefer, Claus
2008-01-01
The open problem of constructing a consistent and experimentally tested quantum theory of the gravitational field has its place at the heart of fundamental physics. The main approaches can be roughly divided into two classes: either one seeks a unified quantum framework of all interactions or one starts with a direct quantization of general relativity. In the first class, string theory (M-theory) is the only known example. In the second class, one can make an additional methodological distinction: while covariant approaches such as path-integral quantization use the four-dimensional metric as an essential ingredient of their formalism, canonical approaches start with a foliation of spacetime into spacelike hypersurfaces in order to arrive at a Hamiltonian formulation. The present book is devoted to one of the canonical approaches-loop quantum gravity. It is named modern canonical quantum general relativity by the author because it uses connections and holonomies as central variables, which are analogous to the variables used in Yang-Mills theories. In fact, the canonically conjugate variables are a holonomy of a connection and the flux of a non-Abelian electric field. This has to be contrasted with the older geometrodynamical approach in which the metric of three-dimensional space and the second fundamental form are the fundamental entities, an approach which is still actively being pursued. It is the author's ambition to present loop quantum gravity in a way in which every step is formulated in a mathematically rigorous form. The formal Leitmotiv of loop quantum gravity is background independence. Non-gravitational theories are usually quantized on a given non-dynamical background. In contrast, due to the geometrical nature of gravity, no such background exists in quantum gravity. Instead, the notion of a background is supposed to emerge a posteriori as an approximate notion from quantum states of geometry. As a consequence, the standard ultraviolet divergences of
A canonical approach to forces in molecules
Energy Technology Data Exchange (ETDEWEB)
Walton, Jay R. [Department of Mathematics, Texas A& M University, College Station, TX 77843-3368 (United States); Rivera-Rivera, Luis A., E-mail: rivera@chem.tamu.edu [Department of Chemistry, Texas A& M University, College Station, TX 77843-3255 (United States); Lucchese, Robert R.; Bevan, John W. [Department of Chemistry, Texas A& M University, College Station, TX 77843-3255 (United States)
2016-08-02
Highlights: • Derivation of canonical representation of molecular force. • Correlation of derivations with accurate results from Born–Oppenheimer potentials. • Extension of methodology to Mg{sub 2}, benzene dimer, and water dimer. - Abstract: In previous studies, we introduced a generalized formulation for canonical transformations and spectra to investigate the concept of canonical potentials strictly within the Born–Oppenheimer approximation. Data for the most accurate available ground electronic state pairwise intramolecular potentials in H{sub 2}{sup +}, H{sub 2}, HeH{sup +}, and LiH were used to rigorously establish such conclusions. Now, a canonical transformation is derived for the molecular force, F(R), with H{sub 2}{sup +} as molecular reference. These transformations are demonstrated to be inherently canonical to high accuracy but distinctly different from those corresponding to the respective potentials of H{sub 2}, HeH{sup +}, and LiH. In this paper, we establish the canonical nature of the molecular force which is key to fundamental generalization of canonical approaches to molecular bonding. As further examples Mg{sub 2}, benzene dimer and to water dimer are also considered within the radial limit as applications of the current methodology.
Trace anomalies and chiral Ward identities
International Nuclear Information System (INIS)
Yang Jifeng
2004-01-01
In a simple Abelian spinor field theory, the canonical trace identities for certain axial-vector and axial-scalar operators are re-examined in dimensional regularization, some disagreements with previous results are found and an interesting new phenomenon is observed and briefly discussed
Canonical pseudotensors, Sparling's form and Noether currents
International Nuclear Information System (INIS)
Szabados, L.B.
1991-09-01
The canonical energy - momentum and spin pseudotensors of the Einstein theory are studied in two ways. First they are studied in the framework of Lagrangian formalism. It is shown, that for first order Lagrangian and rigid basis description the canonical energy - momentum, the canonical spin, and the Noether current are tensorial quantities, and the canonial energy - momentum and spin tensors satisfy the tensorial Belinfante-Rosenfeld equations. Then the differential geometric unification and reformulation of the previous different pseudotensorial approaches is given. Finally, for any vector field on the spacetime an (m-1) form, called the Noether form is defined. (K.A.) 34 refs
Grand Hotel prijutil hudozhnikov
2004-01-01
Raadioajakirjanik Lea Veelmaa lindistas "Kunstikanali" 2004. a. esimese saate Grand Hotel Viljandis. Saatekülaliseks oli maalikunstnik Andres Tolts. Toltsi kaheksa akrüülmaali on eksponeeritud hotelli fuajees ja restoranis
... grand mal seizures include: A family history of seizure disorders Any injury to the brain from trauma, a ... the risk of birth defects. If you have epilepsy and plan to become pregnant, work with your ...
The linear canonical transformation : definition and properties
Bastiaans, Martin J.; Alieva, Tatiana; Healy, J.J.; Kutay, M.A.; Ozaktas, H.M.; Sheridan, J.T.
2016-01-01
In this chapter we introduce the class of linear canonical transformations, which includes as particular cases the Fourier transformation (and its generalization: the fractional Fourier transformation), the Fresnel transformation, and magnifier, rotation and shearing operations. The basic properties
2010-07-01
... REPRESENTATION OF OTHERS BEFORE THE PATENT AND TRADEMARK OFFICE Patent and Trademark Office Code of Professional Responsibility § 10.21 Canon 1. A practitioner should assist in maintaining the integrity and competence of the...
Semiotic Analysis of Canon Camera Advertisements
INDRAWATI, SUSAN
2015-01-01
Keywords: Semiotic Analysis, Canon Camera, Advertisement. Advertisement is a medium to deliver message to people with the goal to influence the to use certain products. Semiotics is applied to develop a correlation within element used in an advertisement. In this study, the writer chose the Semiotic analysis of canon camera advertisement as the subject to be analyzed using semiotic study based on Peirce's theory. Semiotic approach is employed in interpreting the sign, symbol, icon, and index ...
The canonical ensemble redefined - 1: Formalism
International Nuclear Information System (INIS)
Venkataraman, R.
1984-12-01
For studying the thermodynamic properties of systems we propose an ensemble that lies in between the familiar canonical and microcanonical ensembles. We point out the transition from the canonical to microcanonical ensemble and prove from a comparative study that all these ensembles do not yield the same results even in the thermodynamic limit. An investigation of the coupling between two or more systems with these ensembles suggests that the state of thermodynamical equilibrium is a special case of statistical equilibrium. (author)
The dark sector from interacting canonical and non-canonical scalar fields
International Nuclear Information System (INIS)
De Souza, Rudinei C; Kremer, Gilberto M
2010-01-01
In this work general models with interactions between two canonical scalar fields and between one non-canonical (tachyon type) and one canonical scalar field are investigated. The potentials and couplings to the gravity are selected through the Noether symmetry approach. These general models are employed to describe interactions between dark energy and dark matter, with the fields being constrained by the astronomical data. The cosmological solutions of some cases are compared with the observed evolution of the late Universe.
Directory of Open Access Journals (Sweden)
Alexander M Many
Full Text Available The characterization of mammary stem cells, and signals that regulate their behavior, is of central importance in understanding developmental changes in the mammary gland and possibly for targeting stem-like cells in breast cancer. The canonical Wnt/β-catenin pathway is a signaling mechanism associated with maintenance of self-renewing stem cells in many tissues, including mammary epithelium, and can be oncogenic when deregulated. Wnt1 and Wnt3a are examples of ligands that activate the canonical pathway. Other Wnt ligands, such as Wnt5a, typically signal via non-canonical, β-catenin-independent, pathways that in some cases can antagonize canonical signaling. Since the role of non-canonical Wnt signaling in stem cell regulation is not well characterized, we set out to investigate this using mammosphere formation assays that reflect and quantify stem cell properties. Ex vivo mammosphere cultures were established from both wild-type and Wnt1 transgenic mice and were analyzed in response to manipulation of both canonical and non-canonical Wnt signaling. An increased level of mammosphere formation was observed in cultures derived from MMTV-Wnt1 versus wild-type animals, and this was blocked by treatment with Dkk1, a selective inhibitor of canonical Wnt signaling. Consistent with this, we found that a single dose of recombinant Wnt3a was sufficient to increase mammosphere formation in wild-type cultures. Surprisingly, we found that Wnt5a also increased mammosphere formation in these assays. We confirmed that this was not caused by an increase in canonical Wnt/β-catenin signaling but was instead mediated by non-canonical Wnt signals requiring the receptor tyrosine kinase Ror2 and activity of the Jun N-terminal kinase, JNK. We conclude that both canonical and non-canonical Wnt signals have positive effects promoting stem cell activity in mammosphere assays and that they do so via independent signaling mechanisms.
Canonical structure and extra mode of generalized unimodular gravity
Bufalo, Rodrigo; Oksanen, Markku
2018-02-01
We consider a recently proposed generalization of unimodular gravity, where the lapse function is constrained to be equal to a function of the determinant of the spatial metric f (h ), as a potential origin of a dark fluid with a generally h -dependent equation of state parameter. We establish the Hamiltonian analysis and the canonical path integral for the theory. All the special cases that do not match unimodular gravity involve the violation of general covariance, and consequently the physical content of the theory is changed significantly. Particularly, the case of a constant function f is shown to contain an extra physical degree of freedom in each point of space. Physical consequences of the extra degree of freedom are studied in a linearized theory, where the extra mode is carried by the trace of the metric perturbation. The trace mode does not propagate as a wave, since it satisfies an elliptic partial differential equation in spacetime. Consequently, the trace perturbation is shown to grow exponentially with time, which implies instability. The case of a general f (h ) involves additional second-class constraints, which implies the presence of an extra global degree of freedom that depends only on time (instead of the extra local degree of freedom in the case of a constant f ).
Directory of Open Access Journals (Sweden)
Cláudio Ricken
2009-09-01
Full Text Available The analysis of the material obtained in the rescue of archaeological sites in the area surrounding the Hydroelectric Plant of Machadinho, Rio Grande do Sul, revealed that a considerable amount of bones and fish scales incorporated in the alimentary remains. Using an osteological collection as reference, we identified remains of Salminus brasiliensis (Cuvier, 1816 (Characidae, Brycon orbignyanus (Valenciennes, 1849 (Characidae, Pogonopoma obscurum Quevedo & Reis, 2002 (Loricariidae, Hemiancistrus fuliginosus Cardoso & Malabarba, 1999, Prochilodus lineatus (Valenciennes, 1836 (Prochilodontidae, Schizodon sp. (Anostomidae, Leporinus sp. (Anostomidae, Hoplias sp. (Erythrinidae, Hypostomus sp. (Loricariidae and Crenicichla sp. (Cichlidae. Based on specimens from fish collections, regressions were obtained comparing the size of the pre-maxillary bone in Crenicichla spp. and the length of the pectoral fin spine of Hemiancistrus fuliginosus, Pogonopoma obscurum and Hypostomus spp, with the standard length and weight of corresponding specimens. The estimated size and weight of the specimens obtained from fish remains in the archaeological sites varied between 79.7-153.9 mm and 13.5-33.9 g for Hemiancistrus fuliginosus, 158.2-151.0 mm and 179.5-194.3 g for Pogonopoma obscurum, 117.1-166.2 mm and 86.6-93.1 g for Crenicichla spp., and 62.2-397.2 mm and 34-20.3 g for Hypostomus spp. Therefore using these estimates of standard lengths and weights it was possible to formulate a hypotheses on the fishing technology used by the inhabitants of these sites.
Sparse canonical correlation analysis: new formulation and algorithm.
Chu, Delin; Liao, Li-Zhi; Ng, Michael K; Zhang, Xiaowei
2013-12-01
In this paper, we study canonical correlation analysis (CCA), which is a powerful tool in multivariate data analysis for finding the correlation between two sets of multidimensional variables. The main contributions of the paper are: 1) to reveal the equivalent relationship between a recursive formula and a trace formula for the multiple CCA problem, 2) to obtain the explicit characterization for all solutions of the multiple CCA problem even when the corresponding covariance matrices are singular, 3) to develop a new sparse CCA algorithm, and 4) to establish the equivalent relationship between the uncorrelated linear discriminant analysis and the CCA problem. We test several simulated and real-world datasets in gene classification and cross-language document retrieval to demonstrate the effectiveness of the proposed algorithm. The performance of the proposed method is competitive with the state-of-the-art sparse CCA algorithms.
Google Earth Grand Tour Themes
De Paor, D. G.; Whitmeyer, S. J.; Bentley, C.; Dordevic, M. M.
2014-12-01
As part of an NSF TUES Type 3 project entitled "Google Earth for Onsite and Distance Education (GEODE)," we are assembling a "Grand Tour" of locations on Earth and other terrestrial bodies that every geoscience student should know about and visit at least in virtual reality. Based on feedback from colleagues at previous meetings, we have identified nine Grand Tour themes: "Plates and Plumes," "Rocks and Regions," "Geology Through Time," "The Mapping Challenge*," "U.S. National Parks*," "The Magical Mystery Tour*," "Resources and Hazards," "Planets and Moons," and "Top of the Pops." Themes marked with an asterisk are most developed at this stage and will be demonstrated in real time. The Mapping Challenge invites students to trace geological contacts, measure bedding strike and dip and the plunge, trend, and facing of a fold. There is an advanced tool for modeling periclinal folds. The challenge is presented in a game-like format with an emphasis on puzzle-solving that will appeal to students regardless of gender. For the tour of U.S. national parks, we divided the most geologically important parks into four groups—Western Pacific, West Coast, Rockies, and East Coast. We are combining our own team's GigaPan imagery with imagery already available on the Internet. There is a great deal of imagery just waiting to be annotated for geological education purposes. The Magical Mystery Tour takes students to Google Streetview locations selected by instructors. Students are presented with questions or tasks and are given automatic feedback. Other themes are under development. Within each theme, we are crowd-sourcing contributions from colleagues and inviting colleagues to vote for or against proposed locations and student interactions. The GEODE team includes the authors and: Heather Almquist, Stephen Burgin, Cinzia Cervato, Gene Cooper, Paul Karabinos, Terry Pavlis, Jen Piatek, Bill Richards, Jeff Ryan, Ron Schott, Kristen St. John, and Barb Tewksbury.
On the coupling of statistic sum of canonical and large canonical ensemble of interacting particles
International Nuclear Information System (INIS)
Vall, A.N.
2000-01-01
Potentiality of refining the known result based on analytic properties of a great statistical sum, as a function of the absolute activity of the boundary integral contribution into statistical sum, is considered. A strict asymptotic ratio between statistical sums of canonical and large canonical ensemble of interacting particles was derived [ru
Multicollinearity in canonical correlation analysis in maize.
Alves, B M; Cargnelutti Filho, A; Burin, C
2017-03-30
The objective of this study was to evaluate the effects of multicollinearity under two methods of canonical correlation analysis (with and without elimination of variables) in maize (Zea mays L.) crop. Seventy-six maize genotypes were evaluated in three experiments, conducted in a randomized block design with three replications, during the 2009/2010 crop season. Eleven agronomic variables (number of days from sowing until female flowering, number of days from sowing until male flowering, plant height, ear insertion height, ear placement, number of plants, number of ears, ear index, ear weight, grain yield, and one thousand grain weight), 12 protein-nutritional variables (crude protein, lysine, methionine, cysteine, threonine, tryptophan, valine, isoleucine, leucine, phenylalanine, histidine, and arginine), and 6 energetic-nutritional variables (apparent metabolizable energy, apparent metabolizable energy corrected for nitrogen, ether extract, crude fiber, starch, and amylose) were measured. A phenotypic correlation matrix was first generated among the 29 variables for each of the experiments. A multicollinearity diagnosis was later performed within each group of variables using methodologies such as variance inflation factor and condition number. Canonical correlation analysis was then performed, with and without the elimination of variables, among groups of agronomic and protein-nutritional, and agronomic and energetic-nutritional variables. The canonical correlation analysis in the presence of multicollinearity (without elimination of variables) overestimates the variability of canonical coefficients. The elimination of variables is an efficient method to circumvent multicollinearity in canonical correlation analysis.
The Bargmann transform and canonical transformations
International Nuclear Information System (INIS)
Villegas-Blas, Carlos
2002-01-01
This paper concerns a relationship between the kernel of the Bargmann transform and the corresponding canonical transformation. We study this fact for a Bargmann transform introduced by Thomas and Wassell [J. Math. Phys. 36, 5480-5505 (1995)]--when the configuration space is the two-sphere S 2 and for a Bargmann transform that we introduce for the three-sphere S 3 . It is shown that the kernel of the Bargmann transform is a power series in a function which is a generating function of the corresponding canonical transformation (a classical analog of the Bargmann transform). We show in each case that our canonical transformation is a composition of two other canonical transformations involving the complex null quadric in C 3 or C 4 . We also describe quantizations of those two other canonical transformations by dealing with spaces of holomorphic functions on the aforementioned null quadrics. Some of these quantizations have been studied by Bargmann and Todorov [J. Math. Phys. 18, 1141-1148 (1977)] and the other quantizations are related to the work of Guillemin [Integ. Eq. Operator Theory 7, 145-205 (1984)]. Since suitable infinite linear combinations of powers of the generating functions are coherent states for L 2 (S 2 ) or L 2 (S 3 ), we show finally that the studied Bargmann transforms are actually coherent states transforms
Dictionary-Based Tensor Canonical Polyadic Decomposition
Cohen, Jeremy Emile; Gillis, Nicolas
2018-04-01
To ensure interpretability of extracted sources in tensor decomposition, we introduce in this paper a dictionary-based tensor canonical polyadic decomposition which enforces one factor to belong exactly to a known dictionary. A new formulation of sparse coding is proposed which enables high dimensional tensors dictionary-based canonical polyadic decomposition. The benefits of using a dictionary in tensor decomposition models are explored both in terms of parameter identifiability and estimation accuracy. Performances of the proposed algorithms are evaluated on the decomposition of simulated data and the unmixing of hyperspectral images.
Democracy and "Grand" Corruption.
Rose-Ackerman, Susan
1996-01-01
Defines "grand" corruption as that occurring at the higher levels of a political system and involving large sums of money. Discusses the impact and incentives for this level of corruption as well as various government responses. Identifies multinational corporations as the major malefactors. (MJP)
International Nuclear Information System (INIS)
Adams, A.; Bond, R.; Coleman, L.; Rollefson, A.; Wold, D.; Bratton, C.B.; Gurr, H.; Kropp, W.; Nelson, M.; Price, L.R.; Reines, F.; Schultz, J.; Sobel, H.; Svoboda, R.; Yodh, G.; Burnett, T.; Chaloupka, V.; Wilkes, R.J.; Cherry, M.; Ellison, S.B.; Guzik, T.G.; Wefel, J.; Gaidos, J.; Loeffler, F.; Sembroski, G.; Wilson, C.; Goodman, J.; Haines, T.J.; Kielczewska, D.; Lane, C.; Steinberg, R.; Lieber, M.; Nagle, D.; Potter, M.; Tripp, R.
1990-01-01
In this paper we present a detector facility which meets the requirements outlined above for a next-generation instrument. GRANDE (Gamma Ray and Neutrino DEtector) is an imaging, water Cerenkov detector, which combines in one facility an extensive air shower array and a high-energy neutrino detector. (orig.)
International Nuclear Information System (INIS)
Wilson, C.L.; Bratton, C.B.; Gurr, J.; Kropp, W.; Nelson, M.; Sobel, H.; Svoboda, R.; Yodh, G.; Burnett, T.; Chaloupka, V.; Wilkes, R.J.; Cherry, M.; Ellison, S.B.; Guzik, T.G.; Wefel, J.; Gaidos, J.; Loeffler, F.; Sembroski, G.; Goodman, J.; Haines, T.J.; Kielczewska, D.; Lane, C.; Steinberg, R.; Lieber, M.; Nagle, D.; Potter, M.; Tripp, R.
1990-01-01
A brief description of the Gamma Ray And Neutrino Detector Experiment (GRANDE) is presented. The detector elements and electronics are described. The trigger logic for the array is then examined. The triggers for the Gamma Ray and the Neutrino portions of the array are treated separately. (orig.)
African Journals Online (AJOL)
Geo
l'estuaire du fleuve Comoé (Grand-Bassam, Côte d'Ivoire). Kouassi Laurent ADOPO1*, Apie Colette AKOBE1, Etche Mireille AMANI2,. Sylvain MONDE3 et Kouamé AKA3. (1)Laboratoire de Géologie Marine, Sédimentologie et Environnement, Centre de Recherche en Ecologie,. Université Felix Houphouet Boigny Abidjan, ...
International Nuclear Information System (INIS)
Warner, M.
1987-01-01
What is the current state of quantitative trace analytical chemistry? What are today's research efforts? And what challenges does the future hold? These are some of the questions addressed at a recent four-day symposium sponsored by the National Bureau of Standards (NBS) entitled Accuracy in Trace Analysis - Accomplishments, Goals, Challenges. The two plenary sessions held on the first day of the symposium reviewed the history of quantitative trace analysis, discussed the present situation from academic and industrial perspectives, and summarized future needs. The remaining three days of the symposium consisted of parallel sessions dealing with the measurement process; quantitation in materials; environmental, clinical, and nutrient analysis; and advances in analytical techniques
Canonical vs. micro-canonical sampling methods in a 2D Ising model
International Nuclear Information System (INIS)
Kepner, J.
1990-12-01
Canonical and micro-canonical Monte Carlo algorithms were implemented on a 2D Ising model. Expressions for the internal energy, U, inverse temperature, Z, and specific heat, C, are given. These quantities were calculated over a range of temperature, lattice sizes, and time steps. Both algorithms accurately simulate the Ising model. To obtain greater than three decimal accuracy from the micro-canonical method requires that the more complicated expression for Z be used. The overall difference between the algorithms is small. The physics of the problem under study should be the deciding factor in determining which algorithm to use. 13 refs., 6 figs., 2 tabs
Infants' Recognition of Objects Using Canonical Color
Kimura, Atsushi; Wada, Yuji; Yang, Jiale; Otsuka, Yumiko; Dan, Ippeita; Masuda, Tomohiro; Kanazawa, So; Yamaguchi, Masami K.
2010-01-01
We explored infants' ability to recognize the canonical colors of daily objects, including two color-specific objects (human face and fruit) and a non-color-specific object (flower), by using a preferential looking technique. A total of 58 infants between 5 and 8 months of age were tested with a stimulus composed of two color pictures of an object…
Canonical sampling of a lattice gas
International Nuclear Information System (INIS)
Mueller, W.F.
1997-01-01
It is shown that a sampling algorithm, recently proposed in conjunction with a lattice-gas model of nuclear fragmentation, samples the canonical ensemble only in an approximate fashion. A residual weight factor has to be taken into account to calculate correct thermodynamic averages. Then, however, the algorithm is numerically inefficient. copyright 1997 The American Physical Society
Conformal constraint in canonical quantum gravity
t Hooft, G.
2010-01-01
Perturbative canonical quantum gravity is considered, when coupled to a renormalizable model for matter fields. It is proposed that the functional integral over the dilaton field should be disentangled from the other integrations over the metric fields. This should generate a conformally invariant
Contextuality in canonical systems of random variables
Dzhafarov, Ehtibar N.; Cervantes, Víctor H.; Kujala, Janne V.
2017-10-01
Random variables representing measurements, broadly understood to include any responses to any inputs, form a system in which each of them is uniquely identified by its content (that which it measures) and its context (the conditions under which it is recorded). Two random variables are jointly distributed if and only if they share a context. In a canonical representation of a system, all random variables are binary, and every content-sharing pair of random variables has a unique maximal coupling (the joint distribution imposed on them so that they coincide with maximal possible probability). The system is contextual if these maximal couplings are incompatible with the joint distributions of the context-sharing random variables. We propose to represent any system of measurements in a canonical form and to consider the system contextual if and only if its canonical representation is contextual. As an illustration, we establish a criterion for contextuality of the canonical system consisting of all dichotomizations of a single pair of content-sharing categorical random variables. This article is part of the themed issue `Second quantum revolution: foundational questions'.
DNA pattern recognition using canonical correlation algorithm
Indian Academy of Sciences (India)
2015-09-28
Sep 28, 2015 ... were considered as the two views, and statistically significant relationships were established between these two ... Canonical correlation analysis is to find two sets of basis ..... Jing XY, Li S, Lan C, Zhang D, Yang JY and Liu Q 2011 Color ... Yu S, Yu K, Tresp V and Kriegel HP 2006 Multi-output regularized.
Universal canonical entropy for gravitating systems
Indian Academy of Sciences (India)
Similar to this is the case of ref. [12] which also uses the saddle point approximation to express the microcanonical entropy in terms of the canonical entropy [12a]. Recalling that there is at least 'circumstantial' evidence that the microcanonical entropy has a 'universal' form [13–15], identical to that obtained in ref. [6] quoted.
Canonical analysis based on mutual information
DEFF Research Database (Denmark)
Nielsen, Allan Aasbjerg; Vestergaard, Jacob Schack
2015-01-01
combinations with the information theoretical measure mutual information (MI). We term this type of analysis canonical information analysis (CIA). MI allows for the actual joint distribution of the variables involved and not just second order statistics. While CCA is ideal for Gaussian data, CIA facilitates...
Generalized canonical correlation analysis with missing values
M. van de Velden (Michel); Y. Takane
2009-01-01
textabstractTwo new methods for dealing with missing values in generalized canonical correlation analysis are introduced. The first approach, which does not require iterations, is a generalization of the Test Equating method available for principal component analysis. In the second approach,
On the canonical treatment of Lagrangian constraints
International Nuclear Information System (INIS)
Barbashov, B.M.
2001-01-01
The canonical treatment of dynamic systems with manifest Lagrangian constraints proposed by Berezin is applied to concrete examples: a special Lagrangian linear in velocities, relativistic particles in proper time gauge, a relativistic string in orthonormal gauge, and the Maxwell field in the Lorentz gauge
Kuidas Canon suureks kasvas / Andres Eilart
Eilart, Andres
2004-01-01
Jaapani kaamerate ja büroomasinate tootja Canon Groupi arengust, tegevusest kolmes regioonis - USA-s, Euroopas ja Aasias ning ettevõtte pikaajalise edu põhjustest - ärifilosoofiast ning ajastatud tootearendusest. Vt. samas: Firma esialgne nimi oli Kwanon; Konkurendid koonduvad
Probing the small distance structure of canonical
t Hooft, G.
2010-01-01
In canonical quantum gravity, the formal functional integral includes an integration over the local conformal factor, and we propose to perform the functional integral over this factor before doing any of the other functional integrals. By construction, the resulting effective theory would be
On the canonical treatment of Lagrangian constraints
International Nuclear Information System (INIS)
Barbashov, B.M.
2001-01-01
The canonical treatment of dynamic systems with manifest Lagrangian constraints proposed by Berezin is applied to concrete examples: a specific Lagrangian linear in velocities, relativistic particles in proper time gauge, a relativistic string in orthonormal gauge, and the Maxwell field in the Lorentz gauge
The Literary Canon in the Age of New Media
DEFF Research Database (Denmark)
Backe, Hans-Joachim
2015-01-01
and mediality of the canon. In a development that has largely gone unnoticed outside German speaking countries, new approaches for discussing current and future processes of canonization have been developed in recent years. One pivotal element of this process has been a thorough re-evaluation new media......The article offers a comparative overview of the diverging courses of the canon debate in Anglophone and Germanophone contexts. While the Anglophone canon debate has focused on the politics of canon composition, the Germanophone canon debate has been more concerned with the malleability...
A Grand Canonical Monte Carlo Molecular Study of a Weak Polyampholyte
Jimenez, Arturo Martinez
2016-01-01
that require a pH-triggerable response. The titration behaviors of diblock and random polyampholytes are simulated as a function of solvent quality, electrostatic strength, and salt concentration. For diblock polyampholyte chains in hydrophobic solvents
Isegawa, Miho; Gao, Jiali; Truhlar, Donald G
2011-08-28
Molecular fragmentation algorithms provide a powerful approach to extending electronic structure methods to very large systems. Here we present a method for including charge transfer between molecular fragments in the explicit polarization (X-Pol) fragment method for calculating potential energy surfaces. In the conventional X-Pol method, the total charge of each fragment is preserved, and charge transfer between fragments is not allowed. The description of charge transfer is made possible by treating each fragment as an open system with respect to the number of electrons. To achieve this, we applied Mermin's finite temperature method to the X-Pol wave function. In the application of this method to X-Pol, the fragments are open systems that partially equilibrate their number of electrons through a quasithermodynamics electron reservoir. The number of electrons in a given fragment can take a fractional value, and the electrons of each fragment obey the Fermi-Dirac distribution. The equilibrium state for the electrons is determined by electronegativity equalization with conservation of the total number of electrons. The amount of charge transfer is controlled by re-interpreting the temperature parameter in the Fermi-Dirac distribution function as a coupling strength parameter. We determined this coupling parameter so as to reproduce the charge transfer energy obtained by block localized energy decomposition analysis. We apply the new method to ten systems, and we show that it can yield reasonable approximations to potential energy profiles, to charge transfer stabilization energies, and to the direction and amount of charge transferred. © 2011 American Institute of Physics
Solano, Carlos J F; Pothula, Karunakar R; Prajapati, Jigneshkumar D; De Biase, Pablo M; Noskov, Sergei Yu; Kleinekathöfer, Ulrich
2016-05-10
All-atom molecular dynamics simulations have a long history of applications studying ion and substrate permeation across biological and artificial pores. While offering unprecedented insights into the underpinning transport processes, MD simulations are limited in time-scales and ability to simulate physiological membrane potentials or asymmetric salt solutions and require substantial computational power. While several approaches to circumvent all of these limitations were developed, Brownian dynamics simulations remain an attractive option to the field. The main limitation, however, is an apparent lack of protein flexibility important for the accurate description of permeation events. In the present contribution, we report an extension of the Brownian dynamics scheme which includes conformational dynamics. To achieve this goal, the dynamics of amino-acid residues was incorporated into the many-body potential of mean force and into the Langevin equations of motion. The developed software solution, called BROMOCEA, was applied to ion transport through OmpC as a test case. Compared to fully atomistic simulations, the results show a clear improvement in the ratio of permeating anions and cations. The present tests strongly indicate that pore flexibility can enhance permeation properties which will become even more important in future applications to substrate translocation.
International Nuclear Information System (INIS)
Langacker, P.
1981-01-01
In this talk I discuss the present status of these theories and of their observational and experimental implications. In section II, I briefly review the standard SU 3 sup(c) x SU 2 x U 1 model of the strong and electroweak interactions. Although phenomenologically successful, the standard model leaves many questions unanswered. Some of these questions are addressed by grand unified theories, which are defined and discussed in Section III. The Georgi-Glashow SU 5 model is described, as are theories based on larger groups such as SO 10 , E 6 , or SO 16 . It is emphasized that there are many possible grand unified theories and that it is an experimental problem not only to test the basic ideas but to discriminate between models. (orig./HSI)
Asymptotically safe grand unification
Energy Technology Data Exchange (ETDEWEB)
Bajc, Borut [J. Stefan Institute,1000 Ljubljana (Slovenia); Sannino, Francesco [CP-Origins & the Danish IAS, University of Southern Denmark,Campusvej 55, DK-5230 Odense M (Denmark); Université de Lyon, France, Université Lyon 1, CNRS/IN2P3, UMR5822 IPNL,F-69622 Villeurbanne Cedex (France)
2016-12-28
Phenomenologically appealing supersymmetric grand unified theories have large gauge representations and thus are not asymptotically free. Their ultraviolet validity is limited by the appearance of a Landau pole well before the Planck scale. One could hope that these theories save themselves, before the inclusion of gravity, by generating an interacting ultraviolet fixed point, similar to the one recently discovered in non-supersymmetric gauge-Yukawa theories. Employing a-maximization, a-theorem, unitarity bounds, as well as positivity of other central charges we nonperturbatively rule out this possibility for a broad class of prime candidates of phenomenologically relevant supersymmetric grand unified theories. We also uncover candidates passing these tests, which have either exotic matter or contain one field decoupled from the superpotential. The latter class of theories contains a model with the minimal matter content required by phenomenology.
Canonical methods in classical and quantum gravity: An invitation to canonical LQG
Reyes, Juan D.
2018-04-01
Loop Quantum Gravity (LQG) is a candidate quantum theory of gravity still under construction. LQG was originally conceived as a background independent canonical quantization of Einstein’s general relativity theory. This contribution provides some physical motivations and an overview of some mathematical tools employed in canonical Loop Quantum Gravity. First, Hamiltonian classical methods are reviewed from a geometric perspective. Canonical Dirac quantization of general gauge systems is sketched next. The Hamiltonian formultation of gravity in geometric ADM and connection-triad variables is then presented to finally lay down the canonical loop quantization program. The presentation is geared toward advanced undergradute or graduate students in physics and/or non-specialists curious about LQG.
The ﬁrst endcap disc of CMS being lowered slowly and carefully 100 m underground into the experimental cavern. The disc is one of 15 large pieces to make the grand descent. The uniquely shaped slice, 16 m high, about 50 cm thick weighs 400 tonnes. The two HF that were lowered earlier in November can also be seen in the foreground and background.
Fan fiction, early Greece, and the historicity of canon
Directory of Open Access Journals (Sweden)
Ahuvia Kahane
2016-03-01
Full Text Available The historicity of canon is considered with an emphasis on contemporary fan fiction and early Greek oral epic traditions. The essay explores the idea of canon by highlighting historical variance, exposing wider conceptual isomorphisms, and formulating a revised notion of canonicity. Based on an analysis of canon in early Greece, the discussion moves away from the idea of canon as a set of valued works and toward canon as a practice of containment in response to inherent states of surplus. This view of canon is applied to the practice of fan fiction, reestablishing the idea of canonicity in fluid production environments within a revised, historically specific understanding in early oral traditions on the one hand and in digital cultures and fan fiction on the other. Several examples of early epigraphic Greek texts embedded in oral environments are analyzed and assessed in terms of their implications for an understanding of fan fiction and its modern contexts.
Canonical sound speed profile for the central Bay of Bengal
Digital Repository Service at National Institute of Oceanography (India)
Murty, T.V.R.; PrasannaKumar, S.; Somayajulu, Y.K.; Sastry, J.S.; De Figueiredo, R.J.P.
Following Munk's canonical theory, an algorithm has been presented for computing sound channel parameters in the western and southern Bay of Bengal. The estimated canonical sound speed profile using these parameters has been compared with computed...
An introduction to the theory of canonical matrices
Turnbull, H W
2004-01-01
Thorough and self-contained, this penetrating study of the theory of canonical matrices presents a detailed consideration of all the theory's principal features. Topics include elementary transformations and bilinear and quadratic forms; canonical reduction of equivalent matrices; subgroups of the group of equivalent transformations; and rational and classical canonical forms. The final chapters explore several methods of canonical reduction, including those of unitary and orthogonal transformations. 1952 edition. Index. Appendix. Historical notes. Bibliographies. 275 problems.
Minimal canonical comprehensive Gröbner systems
Manubens, Montserrat; Montes, Antonio
2009-01-01
This is the continuation of Montes' paper "On the canonical discussion of polynomial systems with parameters''. In this paper, we define the Minimal Canonical Comprehensive Gröbner System of a parametric ideal and fix under which hypothesis it exists and is computable. An algorithm to obtain a canonical description of the segments of the Minimal Canonical CGS is given, thus completing the whole MCCGS algorithm (implemented in Maple and Singular). We show its high utility for applications, suc...
DNA pattern recognition using canonical correlation algorithm.
Sarkar, B K; Chakraborty, Chiranjib
2015-10-01
We performed canonical correlation analysis as an unsupervised statistical tool to describe related views of the same semantic object for identifying patterns. A pattern recognition technique based on canonical correlation analysis (CCA) was proposed for finding required genetic code in the DNA sequence. Two related but different objects were considered: one was a particular pattern, and other was test DNA sequence. CCA found correlations between two observations of the same semantic pattern and test sequence. It is concluded that the relationship possesses maximum value in the position where the pattern exists. As a case study, the potential of CCA was demonstrated on the sequence found from HIV-1 preferred integration sites. The subsequences on the left and right flanking from the integration site were considered as the two views, and statistically significant relationships were established between these two views to elucidate the viral preference as an important factor for the correlation.
Normalization as a canonical neural computation
Carandini, Matteo; Heeger, David J.
2012-01-01
There is increasing evidence that the brain relies on a set of canonical neural computations, repeating them across brain regions and modalities to apply similar operations to different problems. A promising candidate for such a computation is normalization, in which the responses of neurons are divided by a common factor that typically includes the summed activity of a pool of neurons. Normalization was developed to explain responses in the primary visual cortex and is now thought to operate throughout the visual system, and in many other sensory modalities and brain regions. Normalization may underlie operations such as the representation of odours, the modulatory effects of visual attention, the encoding of value and the integration of multisensory information. Its presence in such a diversity of neural systems in multiple species, from invertebrates to mammals, suggests that it serves as a canonical neural computation. PMID:22108672
Spanish Literature and Spectrality : Notes on a Haunted Canon
Valdivia, Pablo
In Spanish Literature, Crisis and Spectrality: Notes on a Haunted Canon, Prof. Dr. Pablo Valdivia analyses the contradictions and complexities of the Spanish traditional canon from a transnational approach. Valdivia explores this particular canon as a 'haunted house' by focusing on the specific
Canonical ward identities in generalized QCD
International Nuclear Information System (INIS)
Li Ziping
1995-01-01
The canonical Ward identities for a system with singular higher-order Lagrangian are derived and some application to the generalized QCD are given. The new relations of the Ward identities for gauge ghost field proper vertices are obtained which differ from the usual Ward-Takahashi identities arising from BRS invariance. The expressions for PCAC and generalized PCAC of AVV vertices are also obtained
Canonizing certain Borel equivalences for Silver forcing
Czech Academy of Sciences Publication Activity Database
Doucha, Michal
2012-01-01
Roč. 159, č. 13 (2012), s. 2973-2979 ISSN 0166-8641. [Prague Symposium on General Topology and its Relations to Modern Analysis and Algebra /11./. Prague, 07.08.2011-12.08.2011] Institutional research plan: CEZ:AV0Z10190503 Keywords : Borel equivalence relations * silver ideal * canonical Ramsey theorem Subject RIV: BA - General Mathematics Impact factor: 0.562, year: 2012 http://www.sciencedirect.com/science/article/pii/S0166864112002180#
Are Young Children's Drawings Canonically Biased?
Picard, Delphine; Durand, Karine
2005-01-01
In a between-subjects design, 4-to 6-year-olds were asked to draw from three-dimensional (3D) models, two-and-a-half-dimensional (212D) models with or without depth cues, or two-dimensional (2D) models of a familiar object (a saucepan) in noncanonical orientations (handle at the back or at the front). Results showed that canonical errors were…
Canonical Duality Theory for Topology Optimization
Gao, David Yang
2016-01-01
This paper presents a canonical duality approach for solving a general topology optimization problem of nonlinear elastic structures. By using finite element method, this most challenging problem can be formulated as a mixed integer nonlinear programming problem (MINLP), i.e. for a given deformation, the first-level optimization is a typical linear constrained 0-1 programming problem, while for a given structure, the second-level optimization is a general nonlinear continuous minimization pro...
Il canone linguistico boccacciano, non senza dissenso
Directory of Open Access Journals (Sweden)
Cecilia Casini
2015-06-01
Full Text Available Author of prose’s greatest masterpiece of medieval literature in the vernacular, Giovanni Boccaccio was crucial to defining the Italian language canon, especially since Pietro Bembo proposed its coding in the sixteenth century. Not without controversy, however, since shortly after the publication of Prose Della Volgar Language, Bembo presents the first contrasting theories that support the linguistic model presented by Machiavelli
Generalized operator canonical formalism and gauge invariance
International Nuclear Information System (INIS)
Fradkina, T.E.
1988-01-01
A direct proof is given in the functional representation of the invariance of the S-matrix constructed in the framework of the generalized operator canonical formalism. We find the traditional functional expression for the S-matrix (without point-splitting in the time factor) in the generalized phase space, as well as in the ghost configuration space. An explicit expression is obtained for the effective unitarizing Hamiltonian for gauge theories with constraints of arbitrary rank
Directory of Open Access Journals (Sweden)
Denis Alcides-Rezende
2008-01-01
Full Text Available The objective of this work is to analyse the integration of information systems and information technology resources in the municipal planning of 14 small cities of Rio Grande do Sul (Brazil. The research methodology consisted of a multiple case study together with a convenient non-probabilistic sample chosen through a research protocol. The results demonstrate the difficulties of these cities to organise the municipal data as well as their struggle for accessibility of information and planning for management and control.
Canonical forms for single-qutrit Clifford+T operators
Glaudell, Andrew N.; Ross, Neil J.; Taylor, Jacob M.
2018-01-01
We introduce canonical forms for single qutrit Clifford+T circuits and prove that every single-qutrit Clifford+T operator admits a unique such canonical form. We show that our canonical forms are T-optimal in the sense that among all the single-qutrit Clifford+T circuits implementing a given operator our canonical form uses the least number of T gates. Finally, we provide an algorithm which inputs the description of an operator (as a matrix or a circuit) and constructs the canonical form for ...
A model of individualized canonical microcircuits supporting cognitive operations.
Directory of Open Access Journals (Sweden)
Tim Kunze
Full Text Available Major cognitive functions such as language, memory, and decision-making are thought to rely on distributed networks of a large number of basic elements, called canonical microcircuits. In this theoretical study we propose a novel canonical microcircuit model and find that it supports two basic computational operations: a gating mechanism and working memory. By means of bifurcation analysis we systematically investigate the dynamical behavior of the canonical microcircuit with respect to parameters that govern the local network balance, that is, the relationship between excitation and inhibition, and key intrinsic feedback architectures of canonical microcircuits. We relate the local behavior of the canonical microcircuit to cognitive processing and demonstrate how a network of interacting canonical microcircuits enables the establishment of spatiotemporal sequences in the context of syntax parsing during sentence comprehension. This study provides a framework for using individualized canonical microcircuits for the construction of biologically realistic networks supporting cognitive operations.
Cassini's Grand Finale Overview
Spilker, L. J.
2017-12-01
After 13 years in orbit, the Cassini-Huygens Mission to Saturn ended in a science-rich blaze of glory. Cassini sent back its final bits of unique science data on September 15, 2017, as it plunged into Saturn's atmosphere, vaporizing and satisfying planetary protection requirements. Cassini's final phase covered roughly ten months and ended with the first time exploration of the region between the rings and planet. In late 2016 Cassini transitioned to a series of 20 Ring Grazing orbits with peripases just outside Saturn's F ring, providing close flybys of tiny ring moons, including Pan, Daphnis and Atlas, and high-resolution views of Saturn's A and F rings. A final Titan flyby in late April 2017 propelled Cassini across Saturn's main rings and into its Grand Finale orbits. Comprised of 22 orbits, Cassini repeatedly dove between Saturn's innermost rings and upper atmosphere to answer fundamental questions unattainable earlier in the mission. The last orbit turned the spacecraft into the first Saturn atmosphere probe. The Grand Finale orbits provided highest resolution observations of both the rings and Saturn, and in-situ sampling of the ring particle composition, Saturn's atmosphere, plasma, and innermost radiation belts. The gravitational field was measured to unprecedented accuracy, providing information on the interior structure of the planet, winds in the deeper atmosphere, and mass of the rings. The magnetic field provided insight into the physical nature of the magnetic dynamo and structure of the internal magnetic field. The ion and neutral mass spectrometer sampled the upper atmosphere for molecules that escape the atmosphere in addition to molecules originating from the rings. The cosmic dust analyzer directly sampled the composition from different parts of the main rings for the first time. Fields and particles instruments directly measured the plasma environment between the rings and planet. Science highlights and new mysteries collected in the Grand
Canonical group quantization and boundary conditions
International Nuclear Information System (INIS)
Jung, Florian
2012-01-01
In the present thesis, we study quantization of classical systems with non-trivial phase spaces using the group-theoretical quantization technique proposed by Isham. Our main goal is a better understanding of global and topological aspects of quantum theory. In practice, the group-theoretical approach enables direct quantization of systems subject to constraints and boundary conditions in a natural and physically transparent manner -- cases for which the canonical quantization method of Dirac fails. First, we provide a clarification of the quantization formalism. In contrast to prior treatments, we introduce a sharp distinction between the two group structures that are involved and explain their physical meaning. The benefit is a consistent and conceptually much clearer construction of the Canonical Group. In particular, we shed light upon the 'pathological' case for which the Canonical Group must be defined via a central Lie algebra extension and emphasise the role of the central extension in general. In addition, we study direct quantization of a particle restricted to a half-line with 'hard wall' boundary condition. Despite the apparent simplicity of this example, we show that a naive quantization attempt based on the cotangent bundle over the half-line as classical phase space leads to an incomplete quantum theory; the reflection which is a characteristic aspect of the 'hard wall' is not reproduced. Instead, we propose a different phase space that realises the necessary boundary condition as a topological feature and demonstrate that quantization yields a suitable quantum theory for the half-line model. The insights gained in the present special case improve our understanding of the relation between classical and quantum theory and illustrate how contact interactions may be incorporated.
Canonical group quantization and boundary conditions
Energy Technology Data Exchange (ETDEWEB)
Jung, Florian
2012-07-16
In the present thesis, we study quantization of classical systems with non-trivial phase spaces using the group-theoretical quantization technique proposed by Isham. Our main goal is a better understanding of global and topological aspects of quantum theory. In practice, the group-theoretical approach enables direct quantization of systems subject to constraints and boundary conditions in a natural and physically transparent manner -- cases for which the canonical quantization method of Dirac fails. First, we provide a clarification of the quantization formalism. In contrast to prior treatments, we introduce a sharp distinction between the two group structures that are involved and explain their physical meaning. The benefit is a consistent and conceptually much clearer construction of the Canonical Group. In particular, we shed light upon the 'pathological' case for which the Canonical Group must be defined via a central Lie algebra extension and emphasise the role of the central extension in general. In addition, we study direct quantization of a particle restricted to a half-line with 'hard wall' boundary condition. Despite the apparent simplicity of this example, we show that a naive quantization attempt based on the cotangent bundle over the half-line as classical phase space leads to an incomplete quantum theory; the reflection which is a characteristic aspect of the 'hard wall' is not reproduced. Instead, we propose a different phase space that realises the necessary boundary condition as a topological feature and demonstrate that quantization yields a suitable quantum theory for the half-line model. The insights gained in the present special case improve our understanding of the relation between classical and quantum theory and illustrate how contact interactions may be incorporated.
Canonical formulation of IIB D-branes
International Nuclear Information System (INIS)
Kamimura, K.
1998-01-01
We find Wess-Zumino actions for kappa invariant type IIB D-branes in explicit forms. A simple and compact expression is obtained by the use of spinor variables which are defined as power series of differential forms. Using the Wess-Zumino actions we develop the canonical formulation and find the complete set of the constraint equations for generic type IIB Dp-branes. The conserved global supersymmetry charges are determined and the algebra containing the central charges can be obtained explicitly. (orig.)
Canonical formalism for coupled beam optics
International Nuclear Information System (INIS)
Kheifets, S.A.
1989-09-01
Beam optics of a lattice with an inter-plane coupling is treated using canonical Hamiltonian formalism. The method developed is equally applicable both to a circular (periodic) machine and to an open transport line. A solution of the equation of a particle motion (and correspondingly transfer matrix between two arbitrary points of the lattice) are described in terms of two amplitude functions (and their derivatives and corresponding phases of oscillations) and four coupling functions, defined by a solution of the system of the first-order nonlinear differential equations derived in the paper. Thus total number of independent parameters is equal to ten. 8 refs
Kato expansion in quantum canonical perturbation theory
Energy Technology Data Exchange (ETDEWEB)
Nikolaev, Andrey, E-mail: Andrey.Nikolaev@rdtex.ru [Institute of Computing for Physics and Technology, Protvino, Moscow Region, Russia and RDTeX LTD, Moscow (Russian Federation)
2016-06-15
This work establishes a connection between canonical perturbation series in quantum mechanics and a Kato expansion for the resolvent of the Liouville superoperator. Our approach leads to an explicit expression for a generator of a block-diagonalizing Dyson’s ordered exponential in arbitrary perturbation order. Unitary intertwining of perturbed and unperturbed averaging superprojectors allows for a description of ambiguities in the generator and block-diagonalized Hamiltonian. We compare the efficiency of the corresponding computational algorithm with the efficiencies of the Van Vleck and Magnus methods for high perturbative orders.
Canonically conjugate pairs and phase operators
International Nuclear Information System (INIS)
Schoenhammer, K.
2002-01-01
For quantum mechanics on a lattice the position ('particle number') operator and the quasimomentum ('phase') operator obey canonical commutation relations (CCRs) only on a dense set of the Hilbert space. We compare exact numerical results for a particle in a linear and a quadratic potential on the lattice with the expectations, when the CCRs are assumed to be strictly obeyed. Only for sufficiently smooth eigenfunctions does this lead to reasonable results. In the long time limit the use of the CCRs can lead to a qualitatively wrong dynamics even if the initial state is in the dense set
Path integrals for arbitrary canonical transformations
International Nuclear Information System (INIS)
Oliveira, L.A.R. de.
1980-01-01
Some aspects of the path integral formulation of quantum mechanics are studied. This formalism is generalized to arbitrary canonical transformations, by means of an association between path integral probalility amplitudes and classical generators of transformations, analogous to the usual Hamiltonian time development phase space expression. Such association turns out to be equivalent to the Weyl quantization rule, and it is also shown that this formalism furnishes a path integral representation for a Lie algebra of a given set of classical generators. Some physical considerations about the path integral quantization procedure and about the relationship between classical and quantum dynamical structures are also discussed. (Author) [pt
Canonical transformations and hamiltonian path integrals
International Nuclear Information System (INIS)
Prokhorov, L.V.
1982-01-01
Behaviour of the Hamiltonian path integrals under canonical transformations produced by a generator, is investigated. An exact form is determined for the kernel of the unitary operator realizing the corresponding quantum transformation. Equivalence rules are found (the Hamiltonian formalism, one-dimensional case) enabling one to exclude non-standard terms from the action. It is shown that the Hamiltonian path integral changes its form under cononical transformations: in the transformed expression besides the classical Hamiltonian function there appear some non-classical terms
Kato expansion in quantum canonical perturbation theory
International Nuclear Information System (INIS)
Nikolaev, Andrey
2016-01-01
This work establishes a connection between canonical perturbation series in quantum mechanics and a Kato expansion for the resolvent of the Liouville superoperator. Our approach leads to an explicit expression for a generator of a block-diagonalizing Dyson’s ordered exponential in arbitrary perturbation order. Unitary intertwining of perturbed and unperturbed averaging superprojectors allows for a description of ambiguities in the generator and block-diagonalized Hamiltonian. We compare the efficiency of the corresponding computational algorithm with the efficiencies of the Van Vleck and Magnus methods for high perturbative orders.
Canonical particle tracking in undulator fields
International Nuclear Information System (INIS)
Wuestefeld, G.; Bahrdt, J.
1991-01-01
A new algebraic mapping routine for particle tracking across wiggler and undulator fields in presented. It is based on a power series expansion of the generating function to guarantee fully canonical transformations. This method is 10 to 100 times faster than integration routines, applied in tracking codes like BETA or RACETRACK. The tracking method presented is not restricted to wigglers and undulators, it can be applied to other magnetic fields as well such as fringing fields of quadrupoles or dipoles if the suggested expansion converges
Convergence analysis of canonical genetic algorithms.
Rudolph, G
1994-01-01
This paper analyzes the convergence properties of the canonical genetic algorithm (CGA) with mutation, crossover and proportional reproduction applied to static optimization problems. It is proved by means of homogeneous finite Markov chain analysis that a CGA will never converge to the global optimum regardless of the initialization, crossover, operator and objective function. But variants of CGA's that always maintain the best solution in the population, either before or after selection, are shown to converge to the global optimum due to the irreducibility property of the underlying original nonconvergent CGA. These results are discussed with respect to the schema theorem.
Grand unification and supergravity
International Nuclear Information System (INIS)
Nanopoulos, D.V.
Grand Unified Theories (GUTs) are very successful, but they suffer from fine-tuning or hierarchy problems. It seems that more symmetry beyond the gauge symmetry is needed and indeed supersymmetric GUTs may provide the correct framework in solving the hierarchy problems. These are reviewed. From the results discussed, it is seen that for the first time in particle physics, gravity seems to play a dominant role. It may be responsible for GUT breaking, SU(2) x U(1) breaking, fermion masses, proton decay and a consistent cosmological picture. Supergravity seems to offer a consistent, effective theory for energies below the Planck scale to N=1 local SUSY but also, in the context of N=8 extended supergravity with a dynamically realized SU(8), there may be a consistent fundamental unified theory of all interactions. (U.K.)
Grand unification: status report
International Nuclear Information System (INIS)
Georgi, H.
1983-01-01
Grand unification is reviewed with regard to the flavor puzzle and the hierarchy puzzle. Progress in CP and the PQWWKDFS axion is reviewed. The neutrino mass and B-L research, the understanding and assimilation of the language of effective theories (which divide the momentum scale up into regions), with focus on the models, are surveyed. Various unified models are organized according to whether they address the hierarchy puzzle or the flavor puzzle. SU(5), SO(10), E6, and Higgs are considered simple and explicit models. Global symmetry addresses hierarchy puzzle, but the rules are unclear. In SO (18), with regard to hierarchy, perturbation theory breaks down. SO (14) fails for hierarchy because of GIM, b and t problems. Supersymmetry and technicolor with regard to flavor puzzle are questioned. The CP solution of ETC and Composite C models (addressing both flavor and hierarchy) is a minus. Composite A model has no evident virtues, and the basic idea of ETC model needs checking
International Nuclear Information System (INIS)
Ellis, J.
1982-01-01
The author gives an introduction to the construction of grand unified theories on the base of the SU(3)xSU(2)xU(1) model of the strong, weak, and electromagnetic interactions. Especially he discusses the proton decay, neutrino masses and oscillations, and cosmological implications in connection with grand unified theories. (orig./HSI)
Baisre, J. A.
2007-01-01
Se responde a las preguntas ¿por qué los mamíferos marinos son los animales más grandes del planeta?, ¿Por qué los peces no pueden ser más grandes?. Éstas y otras interrogantes son respondidas de forma sencilla y clara.
Are neoclassical canons valid for southern Chinese faces?
Directory of Open Access Journals (Sweden)
Yasas S N Jayaratne
Full Text Available BACKGROUND: Proportions derived from neoclassical canons, initially described by Renaissance sculptors and painters, are still being employed as aesthetic guidelines during the clinical assessment of the facial morphology. OBJECTIVE: 1. to determine the applicability of neoclassical canons for Southern Chinese faces and 2. to explore gender differences in relation to the applicability of the neoclassical canons and their variants. METHODOLOGY: 3-D photographs acquired from 103 young adults (51 males and 52 females without facial dysmorphology were used to test applicability of four neoclassical canons. Standard anthropometric measurements that determine the facial canons were made on these 3-D images. The validity of the canons as well as their different variants were quantified. PRINCIPAL FINDINGS: The neoclassical cannons seldom applied to these individuals, and facial three-section and orbital canons did not apply at all. The orbitonasal canon was most frequently applicable, with a frequency of 19%. Significant sexual dimorphism was found relative to the prevalence of the variants of facial three-section and orbitonasal canons. CONCLUSION: The neoclassical canons did not appear to apply to our sample when rigorous quantitative measurements were employed. Thus, they should not be used as esthetic goals for craniofacial surgical interventions.
Directory of Open Access Journals (Sweden)
José D. Dueñas
2014-01-01
Full Text Available A partir del análisis de más de sesenta informes sobre la propia trayectoria lectora de estudiantes de segundo de Magisterio de Educación Infantil y de Educación Primaria durante los cursos 2011/12 y 2012/13, hemos apreciado algunas relaciones, a nuestro juicio, relevantes entre formas de mediación, canon lector y hábitos de lectura. De este modo, hemos observado algunos estilos de mediación que parecen conducir con mayores garantías a trayectorias lectoras de éxito. Hemos clasificado a nuestros informantes en tres grandes grupos de acuerdo con el canon lector en que están instalados: lectores de canon académico, no lectores y lectores de canon social. La mayor o menor calidad de la mediación parece decisiva en buena parte de los casos. Tanto en el ámbito académico como en el familiar la mediación adquiere, en nuestra opinión, mayor eficiencia cuando se traduce en modelos de comportamiento y no solo en recomendaciones verbales, cuando va acompañada de complicidad afectiva o cuando la lectura literaria conecta con aspectos sustanciales de la propia vida. Las prácticas docentes universitarias han de proporcionar sobre todo a los estudiantes experiencias gratificantes de lectura.
Turbulent transport across invariant canonical flux surfaces
International Nuclear Information System (INIS)
Hollenberg, J.B.; Callen, J.D.
1994-07-01
Net transport due to a combination of Coulomb collisions and turbulence effects in a plasma is investigated using a fluid moment description that allows for kinetic and nonlinear effects via closure relations. The model considered allows for ''ideal'' turbulent fluctuations that distort but preserve the topology of species-dependent canonical flux surfaces ψ number-sign,s triple-bond ∫ dF · B number-sign,s triple-bond ∇ x [A + (m s /q s )u s ] in which u s is the flow velocity of the fluid species. Equations for the net transport relative to these surfaces due to ''nonideal'' dissipative processes are found for the total number of particles and total entropy enclosed by a moving canonical flux surface. The corresponding particle transport flux is calculated using a toroidal axisymmetry approximation of the ideal surfaces. The resulting Lagrangian transport flux includes classical, neoclassical-like, and anomalous contributions and shows for the first time how these various contributions should be summed to obtain the total particle transport flux
Canonical quantization of the generalized axial gauge
International Nuclear Information System (INIS)
Haller, K.
1990-01-01
The incompatibility of the constraint A 3 =0 with canonical commutation rules is discussed. A canonical formulation is given of QED and QCD in the axial gauge with n 1 =n 2 =0, n 3 =α and n 0 =β, where α and β are arbitrary real numbers. A Hilbert space is established for the perturbative theory, and a propagator is derived by obtaining an expression for the interaction picture gauge fields, and evaluating the vacuum expectation value of its time-ordered products in the perturbative vacuum. The propagator is expressed in terms of the parameter γ=α/β and is shown to reproduce the light cone gauge propagator when γ=1, and the temporal gauge propagator when γ=0, accommodating various prescriptions for the spurious propagator pole, including the Mandelstam-Leibbrandt and principal value prescriptions. When γ→∞, the generalized axial gauge propagator leads to an expression for the propagator in the A 3 =0 gauge, though in that case the order in which the integration over k 0 is performed, and the limit γ→∞ is taken, affects the resulting expression. Another Hilbert space is established, in which the constraints that include all interactions are implemented in a time independent fashion. It is pointed out that this Hilbert space, and the Hilbert space of the perturbative theory are unitarily equivalent in QED, but that they cannot be unitarily equivalent in QCD. Implications of this fact for the nonperturbative states of QCD are discussed. (orig.)
New constraints for canonical general relativity
International Nuclear Information System (INIS)
Reisenberger, M.P.
1995-01-01
Ashtekar's canonical theory of classical complex Euclidean GR (no Lorentzian reality conditions) is found to be invariant under the full algebra of infinitesimal 4-diffeomorphisms, but non-invariant under some finite proper 4-diffeos when the densitized dreibein, E a i , is degenerate. The breakdown of 4-diffeo invariance appears to be due to the inability of the Ashtekar Hamiltonian to generate births and deaths of E flux loops (leaving open the possibility that a new 'causality condition' forbidding the birth of flux loops might justify the non-invariance of the theory).A fully 4-diffeo invariant canonical theory in Ashtekar's variables, derived from Plebanski's action, is found to have constraints that are stronger than Ashtekar's for rank E< 2. The corresponding Hamiltonian generates births and deaths of E flux loops.It is argued that this implies a finite amplitude for births and deaths of loops in the physical states of quantum GR in the loop representation, thus modifying this (partly defined) theory substantially.Some of the new constraints are second class, leading to difficulties in quantization in the connection representation. This problem might be overcome in a very nice way by transforming to the classical loop variables, or the 'Faraday line' variables of Newman and Rovelli, and then solving the offending constraints.Note that, though motivated by quantum considerations, the present paper is classical in substance. (orig.)
Power, Gender, and Canon Formation in Mexico
Directory of Open Access Journals (Sweden)
Cynthia Steele
1996-01-01
Full Text Available I propose to analyze Castellanos's trajectory from marginalized ethnographer and critic of "latino" society, to presidential insider and ambassador, and the first modern Mexican woman writer to be accepted into the literary canon. I will explore the intersection of politics, gender, and the (self- creation of a literary persona with regard to the following issues: 1 the tension between self-exposure and self-censorship in Castellanos's literary work; 2 Castellanos's intense and problematic relationship with her illegitimate, mestizo half-brother; 3 the coincidences and contradictions between Castellanos's journalistic account of her relationship with her servant Maria Escandon, and Maria's own oral history twenty years later; 4 the tension between depression and dependency, on the one hand, and self-assertiveness and audacity, on the other; 5 the relation between Castellanos's role as ambassador and the personal, apolitical, often frivolous character of her journalistic articles written in Israel; 6 the contradictory readings of Castellanos's death, and the respective implications for her place in the canon; and 7 the implications, for their reception, of the love letters published in Cartas a Ricardo 1994, as opposed to 1974.
Lambert, Rebecca B.; Kolbe, Christine M.; Belzer, Wayne
2008-01-01
The U.S. Geological Survey, in cooperation with the International Boundary and Water Commission - U.S. and Mexican Sections, the National Park Service, the Texas Commission on Environmental Quality, the Secretaria de Medio Ambiente y Recursos Naturales in Mexico, the Area de Proteccion de Flora y Fauna Canon de Santa Elena in Mexico, and the Area de Proteccion de Flora y Fauna Maderas del Carmen in Mexico, collected samples of stream water, streambed sediment, and mine tailings during August 2002 for a study to determine whether trace elements from abandoned mines in the area in and around Big Bend National Park have affected the water and sediment quality in the Rio Grande/Rio Bravo Basin of the United States and Mexico. Samples were collected from eight sites on the main stem of the Rio Grande/Rio Bravo, four Rio Grande/Rio Bravo tributary sites downstream from abandoned mines or mine-tailing sites, and 11 mine-tailing sites. Mines in the area were operated to produce fluorite, germanium, iron, lead, mercury, silver, and zinc during the late 1800s through at least the late 1970s. Moderate (relatively neutral) pHs in stream-water samples collected at the 12 Rio Grande/Rio Bravo main-stem and tributary sites indicate that water is well mixed, diluted, and buffered with respect to the solubility of trace elements. The highest sulfate concentrations were in water samples from tributaries draining the Terlingua mining district. Only the sample from the Rough Run Draw site exceeded the Texas Surface Water Quality Standards general-use protection criterion for sulfate. All chloride and dissolved solids concentrations in water samples were less than the general-use protection criteria. Aluminum, copper, mercury, nickel, selenium, and zinc were detected in all water samples for which each element was analyzed. Cadmium, chromium, and lead were detected in samples less frequently, and silver was not detected in any of the samples. None of the sample concentrations of
DEFF Research Database (Denmark)
Feldt, Liv Egholm
The past is all messiness and blurred relations. However, we tend to sort the messiness out through rigorous analytical studies leaving the messiness behind. Carlo Ginzburgs´ article Clues. Roots of an Evidential Paradigm from 1986 invigorates methodological elements of (historical) research, which...... central methodological elements will be further elaborated and discussed through a historical case study that traces how networks of philanthropic concepts and practices influenced the Danish welfare state in the period from the Danish constitution of 1849 until today. The overall aim of this paper...
Canonical transformations in problems of quantum statistical mechanics
International Nuclear Information System (INIS)
Sankovich, D.P.
1985-01-01
The problem of general canonical transformations in quantum systems possessing a classical analog is considered. The main role plays the Weyl representation of dynamic variables of the quantum system considered. One managed to build a general diagram of canonical transformations in a quantum case and to develop a method for reducing one or another operator to the simplest canonical form. In this case the procedure, being analogous to the Poincare-Birkhof normalization based on the Lie series theory, occurs
Regularised integrals, sums and traces an analytic point of view
Paycha, Sylvie
2012-01-01
"Regularization techniques" is the common name for a variety of methods used to make sense of divergent series, divergent integrals, or traces of linear operators in infinite-dimensional spaces. Such methods are often indispensable in problems of number theory, geometry, quantum field theory, and other areas of mathematics and theoretical physics. However arbitrary and noncanonical they might seem at first glance, regularized sums, integrals, and traces often contain canonical concepts, and the main purpose of this book is to illustrate and explain this. This book provides a unified and self-contained mathematical treatment of various regularization techniques. The author shows how to derive regularized sums, integrals, and traces from certain canonical building blocks of the original divergent object. In the process of putting together these "building blocks", one encounters many problems and ambiguities caused by various so-called anomalies, which are investigated and explained in detail. Nevertheless, it t...
Islamic Canon law encounters South African financing and banking ...
African Journals Online (AJOL)
Islamic Canon law encounters South African financing and banking institutions: Prospects and possibilities for Islamic economic empowerment and Black Economic Empowerment in a Democratic South Africa.
THE TOPOLOGY OF CANONICAL FLUX TUBES IN FLARED JET GEOMETRY
Energy Technology Data Exchange (ETDEWEB)
Lavine, Eric Sander; You, Setthivoine, E-mail: Slavine2@uw.edu, E-mail: syou@aa.washington.edu [University of Washington, 4000 15th Street, NE Aeronautics and Astronautics 211 Guggenheim Hall, Box 352400, Seattle, WA 98195 (United States)
2017-01-20
Magnetized plasma jets are generally modeled as magnetic flux tubes filled with flowing plasma governed by magnetohydrodynamics (MHD). We outline here a more fundamental approach based on flux tubes of canonical vorticity, where canonical vorticity is defined as the circulation of the species’ canonical momentum. This approach extends the concept of magnetic flux tube evolution to include the effects of finite particle momentum and enables visualization of the topology of plasma jets in regimes beyond MHD. A flared, current-carrying magnetic flux tube in an ion-electron plasma with finite ion momentum is thus equivalent to either a pair of electron and ion flow flux tubes, a pair of electron and ion canonical momentum flux tubes, or a pair of electron and ion canonical vorticity flux tubes. We examine the morphology of all these flux tubes for increasing electrical currents, different radial current profiles, different electron Mach numbers, and a fixed, flared, axisymmetric magnetic geometry. Calculations of gauge-invariant relative canonical helicities track the evolution of magnetic, cross, and kinetic helicities in the system, and show that ion flow fields can unwind to compensate for an increasing magnetic twist. The results demonstrate that including a species’ finite momentum can result in a very long collimated canonical vorticity flux tube even if the magnetic flux tube is flared. With finite momentum, particle density gradients must be normal to canonical vorticities, not to magnetic fields, so observations of collimated astrophysical jets could be images of canonical vorticity flux tubes instead of magnetic flux tubes.
Gartrell, Nanette
2014-01-01
A winner of 59 Grand Slam championships including a record 9 Wimbledon singles titles, Martina Navratilova is the most successful woman tennis player of the modern era. Martina was inducted into the International Tennis Hall of Fame, named "Tour Player of the Year" seven times by the Women's Tennis Association, declared "Female Athlete of the Year" by the Associated Press, and ranked one of the "Top Forty Athletes of All-Time" by Sports Illustrated. Equally accomplished off the court, Martina is an author, philanthropist, TV commentator, and activist who has dedicated her life to educating people about prejudice and stereotypes. After coming out as a lesbian in 1981, Martina became a tireless advocate of equal rights for lesbian, gay, bisexual, and transgender (LGBT) people, and she has contributed generously to the LGBT community. Martina is the author of seven books, including most recently Shape Your Self: My 6-Step Diet and Fitness Plan to Achieve the Best Shape of your Life, an inspiring guide to healthy living and personal fitness. Martina was diagnosed with breast cancer in 2010.
Magnetic spectrometer Grand Raiden
International Nuclear Information System (INIS)
Fujiwara, M.; Akimune, H.; Daito, I.; Fujimura, H.; Fujita, Y.; Hatanaka, K.; Ikegami, H.; Katayama, I.; Nagayama, K.; Matsuoka, N.; Morinobu, S.; Noro, T.; Yoshimura, M.; Sakaguchi, H.; Sakemi, Y.; Tamii, A.; Yosoi, M.
1999-01-01
A high-resolution magnetic spectrometer called 'Grand Raiden' is operated at the RCNP ring cyclotron facility in Osaka for nuclear physics studies at intermediate energies. This magnetic spectrometer has excellent ion-optical properties. In the design of the spectrometer, the second-order dispersion matching condition has been taken into account, and almost all the aberration terms such as (x vertical bar θ 3 ), (x vertical bar θφ 2 ), (x vertical bar θ 2 δ) and (x vertical bar θδ 2 ) in a third-order matrix calculation are optimized. A large magnetic rigidity of the spectrometer (K = 1400 MeV) gives a great advantage to measure the charge-exchange ( 3 He, t) reactions at 450 MeV. The ability of the high-resolution measurement has been demonstrated. Various coincidence measurements are performed to study the nuclear structures of highly excited states through decay properties of nuclear levels following nuclear reactions at intermediate energies
Clinical physiology grand rounds.
Richards, Jeremy; Schwartzstein, Richard; Irish, Julie; Almeida, Jacqueline; Roberts, David
2013-04-01
Clinical Physiology Grand Rounds (CPGR) is an interactive, case-based conference for medical students designed to: (1) integrate preclinical and clinical learning; (2) promote inductive clinical reasoning; and (3) emphasise students as peer teachers. CPGR specifically encourages mixed learning level student interactions and emphasises the use of concept mapping. We describe the theoretical basis and logistical considerations for an interactive, integrative, mixed-learner environment such as CPGR. In addition, we report qualitative data regarding students' attitudes towards and perceptions of CPGR. Medical students from first to fourth year participate in a monthly, interactive conference. The CPGR was designed to bridge gaps and reinforce linkages between basic science and clinical concepts, and to incorporate interactive vertical integration between preclinical and clinical students. Medical education and content experts use Socratic, interactive teaching methods to develop real-time concept maps to emphasise the presence and importance of linkages across curricula. Student focus groups were held to assess attitudes towards and perceptions of the mixed-learner environment and concept maps in CPGR. Qualitative analyses of focus group transcripts were performed to develop themes and codes describing the students' impressions of CPGR. CPGR is a case-based, interactive conference designed to help students gain an increased appreciation of linkages between basic science and clinical medicine concepts, and an increased awareness of clinical reasoning thought processes. Success is dependent upon explicit attention being given to goals for students' integrated learning. © Blackwell Publishing Ltd 2013.
Consistency of canonical formulation of Horava gravity
International Nuclear Information System (INIS)
Soo, Chopin
2011-01-01
Both the non-projectable and projectable version of Horava gravity face serious challenges. In the non-projectable version, the constraint algebra is seemingly inconsistent. The projectable version lacks a local Hamiltonian constraint, thus allowing for an extra graviton mode which can be problematic. A new formulation (based on arXiv:1007.1563) of Horava gravity which is naturally realized as a representation of the master constraint algebra (instead of the Dirac algebra) studied by loop quantum gravity researchers is presented. This formulation yields a consistent canonical theory with first class constraints; and captures the essence of Horava gravity in retaining only spatial diffeomorphisms as the physically relevant non-trivial gauge symmetry. At the same time the local Hamiltonian constraint is equivalently enforced by the master constraint.
Canonical Wnt signaling in diabetic retinopathy.
Chen, Qian; Ma, Jian-Xing
2017-10-01
Diabetic retinopathy (DR) is a common eye complication of diabetes, and the pathogenic mechanism of DR is still under investigation. The canonical Wnt signaling pathway is an evolutionarily conserved pathway that plays fundamental roles in embryogenesis and adult tissue homeostasis. Wnt signaling regulates expression of multiple genes that control retinal development and eye organogenesis, and dysregulated Wnt signaling plays pathophysiological roles in many ocular diseases, including DR. This review highlights recent progress in studies of Wnt signaling in DR. We discuss Wnt signaling regulation in the retina and dysregulation of Wnt signaling associated with ocular diseases with an emphasis on DR. We also discuss the therapeutic potential of modulating Wnt signaling in DR. Continued studies in this field will advance our current understanding on DR and contribute to the development of new treatments. Copyright © 2017 Elsevier Ltd. All rights reserved.
Consistency of canonical formulation of Horava gravity
Energy Technology Data Exchange (ETDEWEB)
Soo, Chopin, E-mail: cpsoo@mail.ncku.edu.tw [Department of Physics, National Cheng Kung University, Tainan, Taiwan (China)
2011-09-22
Both the non-projectable and projectable version of Horava gravity face serious challenges. In the non-projectable version, the constraint algebra is seemingly inconsistent. The projectable version lacks a local Hamiltonian constraint, thus allowing for an extra graviton mode which can be problematic. A new formulation (based on arXiv:1007.1563) of Horava gravity which is naturally realized as a representation of the master constraint algebra (instead of the Dirac algebra) studied by loop quantum gravity researchers is presented. This formulation yields a consistent canonical theory with first class constraints; and captures the essence of Horava gravity in retaining only spatial diffeomorphisms as the physically relevant non-trivial gauge symmetry. At the same time the local Hamiltonian constraint is equivalently enforced by the master constraint.
Improved effective potential by nonlinear canonical transformations
International Nuclear Information System (INIS)
Ritschel, U.
1990-01-01
We generalize the familiar gaussian-effective-potential formalism to a class of non-gaussian trial states. With the help of exact nonlinear canonical transformations, expectation values can be calculated analytically and in closed form. A detailed description of our method, particularly for quadratic and cubic transformations, and of the related renormalization procedure is given. Applications to φ 4 -models in various dimensionalities are treated. We find the expected critical behaviour in two space-time dimensions. In three and four dimensions we observe instabilities which go back the incompleteness of the gaussian-based renormalization. In the appendices it is shown that the quadratic transformation leads to a coherent state in a certain limiting case, and the generalization to systems at finite temperature is performed. (orig.)
A simple algorithm for computing canonical forms
Ford, H.; Hunt, L. R.; Renjeng, S.
1986-01-01
It is well known that all linear time-invariant controllable systems can be transformed to Brunovsky canonical form by a transformation consisting only of coordinate changes and linear feedback. However, the actual procedures for doing this have tended to be overly complex. The technique introduced here is envisioned as an on-line procedure and is inspired by George Meyer's tangent model for nonlinear systems. The process utilizes Meyer's block triangular form as an intermedicate step in going to Brunovsky form. The method also involves orthogonal matrices, thus eliminating the need for the computation of matrix inverses. In addition, the Kronecker indices can be computed as a by-product of this transformation so it is necessary to know them in advance.
Discrete canonical transforms that are Hadamard matrices
International Nuclear Information System (INIS)
Healy, John J; Wolf, Kurt Bernardo
2011-01-01
The group Sp(2,R) of symplectic linear canonical transformations has an integral kernel which has quadratic and linear phases, and which is realized by the geometric paraxial optical model. The discrete counterpart of this model is a finite Hamiltonian system that acts on N-point signals through N x N matrices whose elements also have a constant absolute value, although they do not form a representation of that group. Those matrices that are also unitary are Hadamard matrices. We investigate the manifolds of these N x N matrices under the Sp(2,R) equivalence imposed by the model, and find them to be on two-sided cosets. By means of an algorithm we determine representatives that lead to collections of mutually unbiased bases.
Linear canonical transforms theory and applications
Kutay, M; Ozaktas, Haldun; Sheridan, John
2016-01-01
This book provides a clear and accessible introduction to the essential mathematical foundations of linear canonical transforms from a signals and systems perspective. Substantial attention is devoted to how these transforms relate to optical systems and wave propagation. There is extensive coverage of sampling theory and fast algorithms for numerically approximating the family of transforms. Chapters on topics ranging from digital holography to speckle metrology provide a window on the wide range of applications. This volume will serve as a reference for researchers in the fields of image and signal processing, wave propagation, optical information processing and holography, optical system design and modeling, and quantum optics. It will be of use to graduate students in physics and engineering, as well as for scientists in other areas seeking to learn more about this important yet relatively unfamiliar class of integral transformations.
DEFF Research Database (Denmark)
Fajstrup, Lisbeth; Goubault, Eric; Haucourt, Emmanuel
2012-01-01
in the interleaving semantics of a concurrent program, but rather some equivalence classes. The purpose of this paper is to describe a new algorithm to compute such equivalence classes, and a representative per class, which is based on ideas originating in algebraic topology. We introduce a geometric semantics...... of concurrent languages, where programs are interpreted as directed topological spaces, and study its properties in order to devise an algorithm for computing dihomotopy classes of execution paths. In particular, our algorithm is able to compute a control-flow graph for concurrent programs, possibly containing...... loops, which is “as reduced as possible” in the sense that it generates traces modulo equivalence. A preliminary implementation was achieved, showing promising results towards efficient methods to analyze concurrent programs, with very promising results compared to partial-order reduction techniques....
Canonical symmetry of a constrained Hamiltonian system and canonical Ward identity
International Nuclear Information System (INIS)
Li, Zi-ping
1995-01-01
An algorithm for the construction of the generators of the gauge transformation of a constrained Hamiltonian system is given. The relationships among the coefficients connecting the first constraints in the generator are made clear. Starting from the phase space generating function of the Green function, the Ward identity in canonical formalism is deduced. We point out that the quantum equations of motion in canonical form for a system with singular Lagrangian differ from the classical ones whether Dirac's conjecture holds true or not. Applications of the present formulation to the Abelian and non-Abelian gauge theories are given. The expressions for PCAC and generalized PCAC of the AVV vertex are derived exactly from another point of view. A new form of the Ward identity for gauge-ghost proper vertices is obtained which differs from the usual Ward-Takahashi identity arising from the BRS invariance
The Final Problem: Constructing Coherence in the Holmesian Canon
Directory of Open Access Journals (Sweden)
Camilla Ulleland Hoel
2017-06-01
Full Text Available The death and resurrection of Sherlock Holmes, a contrarian reading in which Holmes helps the murderer, and the century-long tradition of the Holmesian Great Game with its pseudo-scholarly readings in light of an ironic conviction that Holmes is real and Arthur Conan Doyle merely John Watson’s literary agent. This paper relies on these events in the afterlife of Sherlock Holmes in order to trace an outline of the author function as it applies to the particular case of Doyle as the author of the Sherlock Holmes stories. The operations of the author function can be hard to identify in the encounter with the apparently natural unity of the individual work, but these disturbances at the edges of the function make its effects more readily apparent. This article takes as its starting point the apparently strong author figure of the Holmesian Great Game, in which “the canon” is delineated from “apocrypha” in pseudo-religious vocabulary. It argues that while readers willingly discard provisional readings in the face of an incompatible authorial text, the sanctioning authority of the author functions merely as a boundary for interpretation, not as a personal-biographical control over the interpretation itself. On the contrary, the consciously “writerly” reading of the text serves to reinforce the reliance on the text as it is encountered. The clear separation of canon from apocrypha, with the attendant reinforced author function, may have laid the ground not only for the acceptance of contrarian reading, but also for the creation of apocryphal writings like pastiche and fan fiction.
CERN Photo Club (CPC) / Canon Contest - My View of CERN
Steyaert, Didier
2016-01-01
The CERN Photo Club has organized in collaboration with Canon Switzerland a photo contest open to all members of the CERN (Persons with a CERN access card). The only restriction is that the photos must have been taken with a CANON camera (DSLR, bridge or compact) between 1 and 31 October 2016.
LCPT: a program for finding linear canonical transformations
International Nuclear Information System (INIS)
Char, B.W.; McNamara, B.
1979-01-01
This article describes a MACSYMA program to compute symbolically a canonical linear transformation between coordinate systems. The difficulties in implementation of this canonical small physics problem are also discussed, along with the implications that may be drawn from such difficulties about widespread MACSYMA usage by the community of computational/theoretical physicists
A canonical-literary reading of Lamentations 5 | Kang | HTS ...
African Journals Online (AJOL)
This article presents a canonical and literary reading of Lamentations 5 in the context of the book of Lamentations as a whole. Following the approach by Vanhoozer (1998, 2002) based on speech-act theory, the meaning of Scripture is sought at canonical level, supervening the basic literary level. In Lamentations, as ...
Canonical quantum theory of gravitational field with higher derivatives, 3
International Nuclear Information System (INIS)
Kawasaki, Shoichiro; Kimura, Tadahiko
1983-01-01
A formulation which is invariant under an additional BRS transformation with nilpotency of order two is presented for the canonical theory of the renormalizable quantum gravity with higher derivatives. The canonical quantization is carried out and various equal time (anti-) commutation relations are derived. The asymptotic fields are reanalyzed. The physical particle contents are just the same as those obtained in previous papers. (author)
Canonical Quantum Teleportation of Two-Particle Arbitrary State
Institute of Scientific and Technical Information of China (English)
HAO Xiang; ZHU Shi-Qun
2005-01-01
The canonical quantum teleportation of two-particle arbitrary state is realized by means of phase operator and number operator. The maximally entangled eigenstates between the difference of phase operators and the sum of number operators are considered as the quantum channels. In contrast to the standard quantum teleportation, the different unitary local operation of canonical teleportation can be simplified by a general expression.
Canonical phase diagrams of the 1D Falicov-Kimball model at T = O
Gajek, Z.; Jȩdrzejewski, J.; Lemański, R.
1996-02-01
The Falicov-Kimball model of spinless quantum electrons hopping on a 1-dimensional lattice and of immobile classical ions occupying some lattice sites, with only intrasite coupling between those particles, have been studied at zero temperature by means of well-controlled numerical procedures. For selected values of the unique coupling parameter U the restricted phase diagrams (based on all the periodic configurations of localized particles (ions) with period not greater than 16 lattice constants, typically) have been constructed in the grand-canonical ensemble. Then these diagrams have been translated into the canonical ensemble. Compared to the diagrams obtained in other studies our ones contain more details, in particular they give better insight into the way the mixtures of periodic phases are formed. Our study has revealed several families of new characteristic phases like the generalized most homogeneous and the generalized crenel phases, a first example of a structural phase transition and a tendency to build up an additional symmetry - the hole-particle symmetry with respect to the ions (electrons) only, as U decreases.
Canonical correlations between chemical and energetic characteristics of lignocellulosic wastes
Directory of Open Access Journals (Sweden)
Thiago de Paula Protásio
2012-09-01
Full Text Available Canonical correlation analysis is a statistical multivariate procedure that allows analyzing linear correlation that may exist between two groups or sets of variables (X and Y. This paper aimed to provide canonical correlation analysis between a group comprised of lignin and total extractives contents and higher heating value (HHV with a group of elemental components (carbon, hydrogen, nitrogen and sulfur for lignocellulosic wastes. The following wastes were used: eucalyptus shavings; pine shavings; red cedar shavings; sugar cane bagasse; residual bamboo cellulose pulp; coffee husk and parchment; maize harvesting wastes; and rice husk. Only the first canonical function was significant, but it presented a low canonical R². High carbon, hydrogen and sulfur contents and low nitrogen contents seem to be related to high total extractives contents of the lignocellulosic wastes. The preliminary results found in this paper indicate that the canonical correlations were not efficient to explain the correlations between the chemical elemental components and lignin contents and higher heating values.
A Canonical Approach to the Argument/Adjunct Distinction
Directory of Open Access Journals (Sweden)
Diana Forker
2014-01-01
Full Text Available This paper provides an account of the argument/adjunct distinction implementing the 'canonical approach'. I identify five criteria (obligatoriness, latency, co-occurrence restrictions, grammatical relations, and iterability and seven diagnostic tendencies that can be used to distinguish canonical arguments from canonical adjuncts. I then apply the criteria and tendencies to data from the Nakh-Daghestanian language Hinuq. Hinuq makes extensive use of spatial cases for marking adjunct-like and argument-like NPs. By means of the criteria and tendencies it is possible to distinguish spatial NPs that come close to canonical arguments from those that are canonical adjuncts, and to place the remaining NPs bearing spatial cases within the argument-adjunct continuum.
El Escritor y las Normas del Canon Literario (The Writer and the Norms of the Literary Canon).
Policarpo, Alcibiades
This paper speculates about whether a literary canon exists in contemporary Latin American literature, particularly in the prose genre. The paper points to Carlos Fuentes, Gabriel Garcia Marquez, and Mario Vargas Llosa as the three authors who might form this traditional and liberal canon with their works "La Muerte de Artemio Cruz"…
Canonical cortical circuits: current evidence and theoretical implications
Directory of Open Access Journals (Sweden)
Capone F
2016-04-01
Full Text Available Fioravante Capone,1,2 Matteo Paolucci,1,2 Federica Assenza,1,2 Nicoletta Brunelli,1,2 Lorenzo Ricci,1,2 Lucia Florio,1,2 Vincenzo Di Lazzaro1,2 1Unit of Neurology, Neurophysiology, Neurobiology, Department of Medicine, Università Campus Bio-Medico di Roma, Rome, Italy; 2Fondazione Alberto Sordi – Research Institute for Aging, Rome, ItalyAbstract: Neurophysiological and neuroanatomical studies have found that the same basic structural and functional organization of neuronal circuits exists throughout the cortex. This kind of cortical organization, termed canonical circuit, has been functionally demonstrated primarily by studies involving visual striate cortex, and then, the concept has been extended to different cortical areas. In brief, the canonical circuit is composed of superficial pyramidal neurons of layers II/III receiving different inputs and deep pyramidal neurons of layer V that are responsible for cortex output. Superficial and deep pyramidal neurons are reciprocally connected, and inhibitory interneurons participate in modulating the activity of the circuit. The main intuition of this model is that the entire cortical network could be modeled as the repetition of relatively simple modules composed of relatively few types of excitatory and inhibitory, highly interconnected neurons. We will review the origin and the application of the canonical cortical circuit model in the six sections of this paper. The first section (The origins of the concept of canonical circuit: the cat visual cortex reviews the experiments performed in the cat visual cortex, from the origin of the concept of canonical circuit to the most recent developments in the modelization of cortex. The second (The canonical circuit in neocortex and third (Toward a canonical circuit in agranular cortex sections try to extend the concept of canonical circuit to other cortical areas, providing some significant examples of circuit functioning in different cytoarchitectonic
Emergent symmetries in the canonical tensor model
Obster, Dennis; Sasakura, Naoki
2018-04-01
The canonical tensor model (CTM) is a tensor model proposing a classically and quantum mechanically consistent description of gravity, formulated as a first-class constraint system with structural similarities to the ADM formalism of general relativity. The classical CTM produces a general relativistic system in a formal continuum limit, the emergence of which should be explained by the quantum CTM. In this paper we study the symmetry properties of a wave function that exactly solves the quantum constraints of the CTM. We have found that it has strong peaks at configurations invariant under some Lie groups, as predicted by a mechanism described in our previous paper. A surprising result is the preference for configurations invariant not only under Lie groups with positive definite signature, but also with Lorentzian signature. Such symmetries could characterize the global structures of spacetimes, and our results are encouraging towards showing spacetime emergence in the CTM. To verify the asymptotic convergence of the wave function we have also analyzed the asymptotic behavior, which for the most part seems to be well under control.
Finite canonical measure for nonsingular cosmologies
International Nuclear Information System (INIS)
Page, Don N.
2011-01-01
The total canonical (Liouville-Henneaux-Gibbons-Hawking-Stewart) measure is finite for completely nonsingular Friedmann-Lemaître-Robertson-Walker classical universes with a minimally coupled massive scalar field and a positive cosmological constant. For a cosmological constant very small in units of the square of the scalar field mass, most of the measure is for nearly de Sitter solutions with no inflation at a much more rapid rate. However, if one restricts to solutions in which the scalar field energy density is ever more than twice the equivalent energy density of the cosmological constant, then the number of e-folds of rapid inflation must be large, and the fraction of the measure is low in which the spatial curvature is comparable to the cosmological constant at the time when it is comparable to the energy density of the scalar field. The measure for such classical FLRWΛ-φ models with both a big bang and a big crunch is also finite. Only the solutions with a big bang that expand forever, or the time-reversed ones that contract from infinity to a big crunch, have infinite measure
The Anonymous Jane Austen: Duelling Canons
Directory of Open Access Journals (Sweden)
Edward Copeland
2017-12-01
Full Text Available This essay initially addresses some theoretical concepts such as adaptation and appropriation. I intend to analyze how Jane Austen herself indulged in her own appropriations from the woman’s canon, in particular through a story entitled Guilt Pursued by Conscience, a tale she found in the “Lady’s Magazine” of 1802. I will show that this tale that claimed Austen’s particular attention was re-appropriated in Emma (although in the broadest sense of parody and, to a lesser extent, in Sense and Sensibility. The second part of the essay, instead, will move on to analyze how novelists of the generation that followed Austen felt free to import dialogue, characters, and plots from Austen’s works, showing no obligation to their source, just as she had done with the “Lady’s” tale. I will mention and comment on a series of novels, especially from the silver fork school, that draw from Austen’s plot, characters and happenings without acknowledging their legacy to their predecessor.
The Schroedinger equation and canonical perturbation theory
International Nuclear Information System (INIS)
Graffi, S.; Paul, T.
1987-01-01
Let T 0 (ℎ,ω)+εV be the Schroedinger operator corresponding to the classical Hamiltonian H 0 (ω)+εV, where H 0 (ω) is the d-dimensional harmonic oscillator with non-resonant frequencies ω=(ω 1 ..., ω d ) and the potential V(q 1 , ..., q d ) is an entire function of order (d+l) -1 . We prove that the algorithm of classical, canonical perturbation theory can be applied to the Schroedinger equation in the Bargmann representation. As a consequence, each term of the Rayleigh-Schroedinger series near any eigenvalue of T 0 (ℎ,ω) admits a convergent expansion in powers of ℎ of initial point the corresponding term of the classical Birkhoff expansion. Moreover if V is an even polynomial, the above result and the KAM theorem show that all eigenvalues λ n (ℎ,ε) of T 0 +εV such that nℎ coincides with a KAM torus are given, up to order ε ∞ , by a quantization formula which reduces to the Bohr-Sommerfeld one up to first order terms in ℎ. (orig.)
Some considerations about literary canon books
Directory of Open Access Journals (Sweden)
Jorge Gregorio Posada Ramírez
2017-06-01
Full Text Available El siguiente texto muestra que las obras clásicas de la literatura, también conocidas como libros del canon, amplían la vida interior de quienes los leen. La permanencia y expansión en tiempo y espacio que hace de un libro una obra clásica se irradia en el lector extendiendo su yo hacia vivencias que van más allá de sus confines biográficos, sociales y culturales. Tomando como ejemplo cuatro obras de la literatura: Edipo Rey de Sófocles, La muerte en Venecia de Thomas Mann, El laberinto de la soledad de Octavio Paz, y Altazor de Vicente Huidobro se expone una interpretación de la manera cómo las obras clásicas de la literatura tienen el poder de profundizar y enriquecer las experiencias corrientes de sus lectores, extendiendo los confines y posibilidades del pensamiento.
Dissolution of Marriage According to Canon Law
Directory of Open Access Journals (Sweden)
MSc. Sulejman Ahmedi
2013-12-01
Full Text Available In the Canon law, dissolution of marriage is not allowed since it was considered sacred and as such cannot break until the two spouses are alive, except only if one of the spouses passes away. But throughout history we find cases when allowed dissolution of the marriage and causes specific conditions set by the church. Thus, according to the Old Testament, if, a man married to a woman, didn’t like something about his wife, should write a request for divorce and allow her to leave his home. Meanwhile according to the New Testament records, divorce is prohibited. Although most Protestants continue to espouse the view that marriage was sacred and as such should not be divorced, from those who had supported the idea of granting the divorce. One of them was Luther, who in his remarks before his preachers said: "In my opinion, the issue of divorce belongs to the law, are not they to whom called for regulation of parental relationships, why not have they the authority to regulate the relations between spouses". Protestant churches allow the dissolution of marriage: a Because of adultery by the wife; allowed by Jesus, b Unjustified abandonment of the marital community; c If there were other reasons: if one spouse refuses to have sexual marriage, if the husband abuses his wife repeatedly and without cause, severe illness of one spouse.
Canonical quantization of gravity and a problem of scattering
International Nuclear Information System (INIS)
Rubakov, V.A.
1980-01-01
Linearized theory of gravity is quantized both in a naive way and as a proper limit of the Dirac-Wheeler-De Witt approach to the quantization of the full theory. The equivalence between the two approaches is established. The problem of scattering in the canonically quantized theory of gravitation is investigated. The concept of the background metric naturally appears in the canonical formalism for this case. The equivalence between canonical and path-integral approaches is established for the problem of scattering. Some kinetical properties of functionals in Wheeler superspace are studied in an appendix. (author)
Covariant canonical quantization of fields and Bohmian mechanics
International Nuclear Information System (INIS)
Nikolic, H.
2005-01-01
We propose a manifestly covariant canonical method of field quantization based on the classical De Donder-Weyl covariant canonical formulation of field theory. Owing to covariance, the space and time arguments of fields are treated on an equal footing. To achieve both covariance and consistency with standard non-covariant canonical quantization of fields in Minkowski spacetime, it is necessary to adopt a covariant Bohmian formulation of quantum field theory. A preferred foliation of spacetime emerges dynamically owing to a purely quantum effect. The application to a simple time-reparametrization invariant system and quantum gravity is discussed and compared with the conventional non-covariant Wheeler-DeWitt approach. (orig.)
Canonical and non-canonical barriers facing antimiR cancer therapeutics.
Cheng, Christopher J; Saltzman, W Mark; Slack, Frank J
2013-01-01
Once considered genetic "oddities", microRNAs (miRNAs) are now recognized as key epigenetic regulators of numerous biological processes, including some with a causal link to the pathogenesis, maintenance, and treatment of cancer. The crux of small RNA-based therapeutics lies in the antagonism of potent cellular targets; the main shortcoming of the field in general, lies in ineffective delivery. Inhibition of oncogenic miRNAs is a relatively nascent therapeutic concept, but as with predecessor RNA-based therapies, success hinges on delivery efficacy. This review will describes the canonical (e.g. pharmacokinetics and clearance, cellular uptake, endosome escape, etc.) and non-canonical (e.g. spatial localization and accessibility of miRNA, technical limitations of miRNA inhibition, off-target impacts, etc.) challenges to the delivery of antisense-based anti-miRNA therapeutics (i.e. antimiRs) for the treatment of cancer. Emphasis will be placed on how the current leading antimiR platforms-ranging from naked chemically modified oligonucleotides to nanoscale delivery vehicles-are affected by and overcome these barriers. The perplexity of antimiR delivery presents both engineering and biological hurdles that must be overcome in order to capitalize on the extensive pharmacological benefits of antagonizing tumor-associated miRNAs.
Interrelations between different canonical descriptions of dissipative systems
International Nuclear Information System (INIS)
Schuch, D; Guerrero, J; López-Ruiz, F F; Aldaya, V
2015-01-01
There are many approaches for the description of dissipative systems coupled to some kind of environment. This environment can be described in different ways; only effective models are being considered here. In the Bateman model, the environment is represented by one additional degree of freedom and the corresponding momentum. In two other canonical approaches, no environmental degree of freedom appears explicitly, but the canonical variables are connected with the physical ones via non-canonical transformations. The link between the Bateman approach and those without additional variables is achieved via comparison with a canonical approach using expanding coordinates, as, in this case, both Hamiltonians are constants of motion. This leads to constraints that allow for the elimination of the additional degree of freedom in the Bateman approach. These constraints are not unique. Several choices are studied explicitly, and the consequences for the physical interpretation of the additional variable in the Bateman model are discussed. (paper)
Canonical and D-transformations in Theories with Constraints
Gitman, Dmitri M.
1995-01-01
A class class of transformations in a super phase space (we call them D-transformations) is described, which play in theories with second-class constraints the role of ordinary canonical transformations in theories without constraints.
On a canonical formulation of field theories with singular Lagrangians
International Nuclear Information System (INIS)
Mal'tsev, V.K.
1978-01-01
An attempt is made to introduce the Routh function formalism into the field theory: only ''nondegenerated'' field components are considered as canonical variables. Electrodynamics and general relativity are considered. The formalism appears to be quite simple and gauge-independent
Interrelations between different canonical descriptions of dissipative systems
Schuch, D.; Guerrero, J.; López-Ruiz, F. F.; Aldaya, V.
2015-04-01
There are many approaches for the description of dissipative systems coupled to some kind of environment. This environment can be described in different ways; only effective models are being considered here. In the Bateman model, the environment is represented by one additional degree of freedom and the corresponding momentum. In two other canonical approaches, no environmental degree of freedom appears explicitly, but the canonical variables are connected with the physical ones via non-canonical transformations. The link between the Bateman approach and those without additional variables is achieved via comparison with a canonical approach using expanding coordinates, as, in this case, both Hamiltonians are constants of motion. This leads to constraints that allow for the elimination of the additional degree of freedom in the Bateman approach. These constraints are not unique. Several choices are studied explicitly, and the consequences for the physical interpretation of the additional variable in the Bateman model are discussed.
Selected topics in grand unification
International Nuclear Information System (INIS)
Seckel, D.
1983-01-01
This dissertation is a collection of four pieces of research dealing with grand unification. The topics are neutron oscillation, CP violation, magnetic monopole abundance and distribution in neutron stars, and a proposal for an inflationary cosmology driven by stress-energy in domain walls
Introduction to grand unification theories
International Nuclear Information System (INIS)
Kang, Kyungsik
1980-01-01
We introduce the Georgi-Glashow model based on the minimal gauge group SU(5) as a prototype grand unification theory of the electroweak and strong interactions. Simple estimation of sin 2 thetasub(W) in the symmetry limit and the renormalization corrections at the energy scale of Msub(W) are given along wich other successes of the SU(5) model
Coordinated Exploration for Grand Challenges
DEFF Research Database (Denmark)
Ørding Olsen, Anders; Sofka, Wolfgang; Grimpe, Christoph
2016-01-01
Grand challenges are among the most complex problems for modern societies. Many governments and foundations provide substantial resources to encourage the search for solutions. Due to the significance of these problems, organizations often form partnerships in what we call search consortia to eng...
An efficient algorithm for calculation of the Luenberger canonical form.
Jordan, D.; Sridhar, B.
1973-01-01
A new algorithm is presented to obtain the Luenberger canonical form for multivariable systems. A distinct feature of the method is that the canonical form is obtained directly and, if necessary, the similarity transformation can be computed. There is a substantial reduction in the amount of computation compared to Luenberger's method. The reduced computations along with Gaussian techniques lend greater inherent accuracy and the ability to refine the solution with additional computations. An example is presented to illustrate the technique.
Canonical transformations method in the potential scattering problem
International Nuclear Information System (INIS)
Pavlenko, Yu.G.
1984-01-01
Canonical formalism of the first order is used in the present paper to solve the problem of scattering and other problems of quantum mechanics. The theory of canonical transformations (CT) being the basis of hamiltonian approach permits to develop several methods of integration being beyond the scope of the standard theory of perturbations. In this case it is essential for numerical counting that the theory permits to obtain algorithm for plotting highest approximations
Canonical algorithms for numerical integration of charged particle motion equations
Efimov, I. N.; Morozov, E. A.; Morozova, A. R.
2017-02-01
A technique for numerically integrating the equation of charged particle motion in a magnetic field is considered. It is based on the canonical transformations of the phase space in Hamiltonian mechanics. The canonical transformations make the integration process stable against counting error accumulation. The integration algorithms contain a minimum possible amount of arithmetics and can be used to design accelerators and devices of electron and ion optics.
Canonical forms of tensor representations and spontaneous symmetry breaking
International Nuclear Information System (INIS)
Cummins, C.J.
1986-01-01
An algorithm for constructing canonical forms for any tensor representation of the classical compact Lie groups is given. This method is used to find a complete list of the symmetry breaking patterns produced by Higgs fields in the third-rank antisymmetric representations of U(n), SU(n) and SO(n) for n<=7. A simple canonical form is also given for kth-rank symmetric tensor representations. (author)
Epidemic contact tracing via communication traces.
Directory of Open Access Journals (Sweden)
Katayoun Farrahi
Full Text Available Traditional contact tracing relies on knowledge of the interpersonal network of physical interactions, where contagious outbreaks propagate. However, due to privacy constraints and noisy data assimilation, this network is generally difficult to reconstruct accurately. Communication traces obtained by mobile phones are known to be good proxies for the physical interaction network, and they may provide a valuable tool for contact tracing. Motivated by this assumption, we propose a model for contact tracing, where an infection is spreading in the physical interpersonal network, which can never be fully recovered; and contact tracing is occurring in a communication network which acts as a proxy for the first. We apply this dual model to a dataset covering 72 students over a 9 month period, for which both the physical interactions as well as the mobile communication traces are known. Our results suggest that a wide range of contact tracing strategies may significantly reduce the final size of the epidemic, by mainly affecting its peak of incidence. However, we find that for low overlap between the face-to-face and communication interaction network, contact tracing is only efficient at the beginning of the outbreak, due to rapidly increasing costs as the epidemic evolves. Overall, contact tracing via mobile phone communication traces may be a viable option to arrest contagious outbreaks.
Epidemic contact tracing via communication traces.
Farrahi, Katayoun; Emonet, Rémi; Cebrian, Manuel
2014-01-01
Traditional contact tracing relies on knowledge of the interpersonal network of physical interactions, where contagious outbreaks propagate. However, due to privacy constraints and noisy data assimilation, this network is generally difficult to reconstruct accurately. Communication traces obtained by mobile phones are known to be good proxies for the physical interaction network, and they may provide a valuable tool for contact tracing. Motivated by this assumption, we propose a model for contact tracing, where an infection is spreading in the physical interpersonal network, which can never be fully recovered; and contact tracing is occurring in a communication network which acts as a proxy for the first. We apply this dual model to a dataset covering 72 students over a 9 month period, for which both the physical interactions as well as the mobile communication traces are known. Our results suggest that a wide range of contact tracing strategies may significantly reduce the final size of the epidemic, by mainly affecting its peak of incidence. However, we find that for low overlap between the face-to-face and communication interaction network, contact tracing is only efficient at the beginning of the outbreak, due to rapidly increasing costs as the epidemic evolves. Overall, contact tracing via mobile phone communication traces may be a viable option to arrest contagious outbreaks.
Process modelling on a canonical basis[Process modelling; Canonical modelling
Energy Technology Data Exchange (ETDEWEB)
Siepmann, Volker
2006-12-20
Based on an equation oriented solving strategy, this thesis investigates a new approach to process modelling. Homogeneous thermodynamic state functions represent consistent mathematical models of thermodynamic properties. Such state functions of solely extensive canonical state variables are the basis of this work, as they are natural objective functions in optimisation nodes to calculate thermodynamic equilibrium regarding phase-interaction and chemical reactions. Analytical state function derivatives are utilised within the solution process as well as interpreted as physical properties. By this approach, only a limited range of imaginable process constraints are considered, namely linear balance equations of state variables. A second-order update of source contributions to these balance equations is obtained by an additional constitutive equation system. These equations are general dependent on state variables and first-order sensitivities, and cover therefore practically all potential process constraints. Symbolic computation technology efficiently provides sparsity and derivative information of active equations to avoid performance problems regarding robustness and computational effort. A benefit of detaching the constitutive equation system is that the structure of the main equation system remains unaffected by these constraints, and a priori information allows to implement an efficient solving strategy and a concise error diagnosis. A tailor-made linear algebra library handles the sparse recursive block structures efficiently. The optimisation principle for single modules of thermodynamic equilibrium is extended to host entire process models. State variables of different modules interact through balance equations, representing material flows from one module to the other. To account for reusability and encapsulation of process module details, modular process modelling is supported by a recursive module structure. The second-order solving algorithm makes it
Suseela, Y V; Narayanaswamy, Nagarjun; Pratihar, Sumon; Govindaraju, Thimmaiah
2018-02-05
The structural diversity and functional relevance of nucleic acids (NAs), mainly deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), are indispensable for almost all living organisms, with minute aberrations in their structure and function becoming causative factors in numerous human diseases. The standard structures of NAs, termed canonical structures, are supported by Watson-Crick hydrogen bonding. Under special physiological conditions, NAs adopt distinct spatial organisations, giving rise to non-canonical conformations supported by hydrogen bonding other than the Watson-Crick type; such non-canonical structures have a definite function in controlling gene expression and are considered as novel diagnostic and therapeutic targets. Development of molecular probes for these canonical and non-canonical DNA/RNA structures has been an active field of research. Among the numerous probes studied, probes with turn-on fluorescence in the far-red (600-750 nm) region are highly sought-after due to minimal autofluorescence and cellular damage. Far-red fluorescent probes are vital for real-time imaging of NAs in live cells as they provide good resolution and minimal perturbation of the cell under investigation. In this review, we present recent advances in the area of far-red fluorescent probes of DNA/RNA and non-canonical G-quadruplex structures. For the sake of continuity and completeness, we provide a brief overview of visible fluorescent probes. Utmost importance is given to design criteria, characteristic properties and biological applications, including in cellulo imaging, apart from critical discussion on limitations of the far-red fluorescent probes. Finally, we offer current and future prospects in targeting canonical and non-canonical NAs specific to cellular organelles, through sequence- and conformation-specific far-red fluorescent probes. We also cover their implications in chemical and molecular biology, with particular focus on decoding various disease
International Nuclear Information System (INIS)
Bertaina, M.; Apel, W.D.; Arteaga-Velázquez, J.C.; Bekk, K.; Blümer, J.; Bozdog, H.; Brancus, I.M.; Buchholz, P.; Cantoni, E.; Chiavassa, A.; Cossavella, F.
2012-01-01
The KASCADE–Grande experiment, located at Karlsruhe Institute of Technology (Germany) is a multi-component extensive air-shower experiment devoted to the study of cosmic rays and their interactions at primary energies 10 14 –10 18 eV. Main goals of the experiment are the measurement of the all-particle energy spectrum and mass composition in the 10 16 –10 18 eV range by sampling charged (N ch ) and muon (N μ ) components of the air shower. The method to derive the energy spectrum and its uncertainties, as well as the implications of the obtained result, is discussed. An overview of the analyses performed by KASCADE–Grande to derive the mass composition of the measured high-energy comic rays is presented as well.
Energy Technology Data Exchange (ETDEWEB)
Bertaina, M., E-mail: bertaina@to.infn.it [Dipartimento di Fisica Generale dell' Universita, Torino (Italy); Apel, W.D. [Institut fuer Kernphysik, KIT - Karlsruher Institut fuer Technologie (Germany); Arteaga-Velazquez, J.C. [Universidad Michoacana, Instituto de Fisica y Matematicas, Morelia (Mexico); Bekk, K. [Institut fuer Kernphysik, KIT - Karlsruher Institut fuer Technologie (Germany); Bluemer, J. [Institut fuer Kernphysik, KIT - Karlsruher Institut fuer Technologie (Germany); Institut fuer Experimentelle Kernphysik, KIT - Karlsruher Institut fuer Technologie (Germany); Bozdog, H. [Institut fuer Kernphysik, KIT - Karlsruher Institut fuer Technologie (Germany); Brancus, I.M. [National Institute of Physics and Nuclear Engineering, Bucharest (Romania); Buchholz, P. [Fachbereich Physik, Universitaet Siegen (Germany); Cantoni, E. [Dipartimento di Fisica Generale dell' Universita, Torino (Italy); Istituto di Fisica dello Spazio Interplanetario, INAF Torino (Italy); Chiavassa, A. [Dipartimento di Fisica Generale dell' Universita, Torino (Italy); Cossavella, F. [Institut fuer Experimentelle Kernphysik, KIT - Karlsruher Institut fuer Technologie (Germany); and others
2012-11-11
The KASCADE-Grande experiment, located at Karlsruhe Institute of Technology (Germany) is a multi-component extensive air-shower experiment devoted to the study of cosmic rays and their interactions at primary energies 10{sup 14}-10{sup 18} eV. Main goals of the experiment are the measurement of the all-particle energy spectrum and mass composition in the 10{sup 16}-10{sup 18} eV range by sampling charged (N{sub ch}) and muon (N{sub {mu}}) components of the air shower. The method to derive the energy spectrum and its uncertainties, as well as the implications of the obtained result, is discussed. An overview of the analyses performed by KASCADE-Grande to derive the mass composition of the measured high-energy comic rays is presented as well.
Cassini's Grand Finale Science Highlights
Spilker, Linda
2017-10-01
After 13 years in orbit, the Cassini-Huygens Mission to Saturn ended in a science-rich blaze of glory. Cassini returned its final bits of unique science data on September 15, 2017, as it plunged into Saturn's atmosphere satisfying planetary protection requirements. Cassini's Grand Finale covered a period of roughly five months and ended with the first time exploration of the region between the rings and planet.The final close flyby of Titan in late April 2017 propelled Cassini across Saturn’s main rings and into its Grand Finale orbits; 22 orbits that repeatedly dove between Saturn’s innermost rings and upper atmosphere making Cassini the first spacecraft to explore this region. The last orbit turned the spacecraft into the first Saturn upper atmospheric probe.The Grand Finale orbits provided highest resolution observations of both the rings and Saturn, and in-situ sampling of the ring particle composition, Saturn's atmosphere, plasma, and innermost radiation belts. The gravitational field was measured to unprecedented accuracy, providing information on the interior structure of the planet, winds in the deeper atmosphere, and mass of the rings. The magnetic field provided insight into the physical nature of the magnetic dynamo and structure of the internal magnetic field. The ion and neutral mass spectrometer sampled the upper atmosphere for molecules that escape the atmosphere in addition to molecules originating from the rings. The cosmic dust analyzer directly sampled the composition from different parts of the main rings for the first time. Fields and particles instruments directly measured the plasma environment between the rings and planet.Science highlights and new mysteries gleaned to date from the Grand Finale orbits will be discussed.The research described in this paper was carried out in part at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. Copyright 2017
Bang, Thöger
2012-01-01
En las escuelas danesas la teoría de los números se ha ido restringiendo gradualmente hasta no incluir sino la demostración de la descomposición univoca de los números enteros en números primos y la demostración del teorema clásico de EUCLIDES sobre la existencia de un número primo arbitrariamente grande.
Grand unification theory and technicolor
International Nuclear Information System (INIS)
Rubakov, V.A.; Shaposhnikov, M.E.
1983-01-01
The lecture course can be considered as introduction to the problems concerning grand unification models. The course is incomplete. Such problems as CP-violations in strong interactions and the problem of gravitational interaction inclusion in the scheme of grand unification theory are not touched upon. Models of early unification, in which strong, weak and electromagnetic interactions are compared according to the ''strength'' at energies of about 10 5 -10 6 GeV, are not discussed. Models with horizontal symmetry, considering different generations of quarks and leptons from one viewpoint, are not analyzed. Cosmological applications of supersymmetric unified theories are not considered. Certain problems of standard elementary particle theory, philosophy of the great unification, general properties of the grand unification models and the main principles of the construction of models: the SU(5) model, models on the SO(10) groups, have been considered. The problem of supersymmetric unification hierarchies, supersymmetric generalization of the minimum SU(5) model, supersymmetry violation and the problem of hierarchies, phenomenology of the o.rand unification models, cosmological application and technicolour, are discussed
The degeneracy problem in non-canonical inflation
International Nuclear Information System (INIS)
Easson, Damien A.; Powell, Brian A.
2013-01-01
While attempting to connect inflationary theories to observational physics, a potential difficulty is the degeneracy problem: a single set of observables maps to a range of different inflaton potentials. Two important classes of models affected by the degeneracy problem are canonical and non-canonical models, the latter marked by the presence of a non-standard kinetic term that generates observables beyond the scalar and tensor two-point functions on CMB scales. The degeneracy problem is manifest when these distinguishing observables go undetected. We quantify the size of the resulting degeneracy in this case by studying the most well-motivated non-canonical theory having Dirac-Born-Infeld Lagrangian. Beyond the scalar and tensor two-point functions on CMB scales, we then consider the possible detection of equilateral non-Gaussianity at Planck-precision and a measurement of primordial gravitational waves from prospective space-based laser interferometers. The former detection breaks the degeneracy with canonical inflation but results in poor reconstruction prospects, while the latter measurement enables a determination of n T which, while not breaking the degeneracy, can be shown to greatly improve the non-canonical reconstruction
A canonical-literary reading of Lamentations 5
Directory of Open Access Journals (Sweden)
Shinman Kang
2009-08-01
Full Text Available This article presents a canonical and literary reading of Lamentations 5 in the context of the book of Lamentations as a whole. Following the approach by Vanhoozer (1998, 2002 based on speech-act theory, the meaning of Scripture is sought at canonical level, supervening the basic literary level. In Lamentations, as polyphonic poetic text, the speaking voices form a very important key for the interpretation of the text. In the polyphonic text of Lamentations, the shifting of the speaking voices occurs between Lamentations 1 and 4. Lamentations 5 is monologic. The theories of Bakhtin (1984 are also used to understand the book of Lamentations. In this book, chapter 5 forms the climax where Jerusalem cries to God. We cannot, however, find God’s answer to this call in Lamentations; we can find it only within the broader text of the Christian canon.
Canonical sectors of five-dimensional Chern-Simons theories
International Nuclear Information System (INIS)
Miskovic, Olivera; Troncoso, Ricardo; Zanelli, Jorge
2005-01-01
The dynamics of five-dimensional Chern-Simons theories is analyzed. These theories are characterized by intricate self couplings which give rise to dynamical features not present in standard theories. As a consequence, Dirac's canonical formalism cannot be directly applied due to the presence of degeneracies of the symplectic form and irregularities of the constraints on some surfaces of phase space, obscuring the dynamical content of these theories. Here we identify conditions that define sectors where the canonical formalism can be applied for a class of non-Abelian Chern-Simons theories, including supergravity. A family of solutions satisfying the canonical requirements is explicitly found. The splitting between first and second class constraints is performed around these backgrounds, allowing the construction of the charge algebra, including its central extension
Escort entropies and divergences and related canonical distribution
International Nuclear Information System (INIS)
Bercher, J.-F.
2011-01-01
We discuss two families of two-parameter entropies and divergences, derived from the standard Renyi and Tsallis entropies and divergences. These divergences and entropies are found as divergences or entropies of escort distributions. Exploiting the nonnegativity of the divergences, we derive the expression of the canonical distribution associated to the new entropies and a observable given as an escort-mean value. We show that this canonical distribution extends, and smoothly connects, the results obtained in nonextensive thermodynamics for the standard and generalized mean value constraints. -- Highlights: → Two-parameter entropies are derived from q-entropies and escort distributions. → The related canonical distribution is derived. → This connects and extends known results in nonextensive statistics.
Canonical duality theory unified methodology for multidisciplinary study
Latorre, Vittorio; Ruan, Ning
2017-01-01
This book on canonical duality theory provides a comprehensive review of its philosophical origin, physics foundation, and mathematical statements in both finite- and infinite-dimensional spaces. A ground-breaking methodological theory, canonical duality theory can be used for modeling complex systems within a unified framework and for solving a large class of challenging problems in multidisciplinary fields in engineering, mathematics, and the sciences. This volume places a particular emphasis on canonical duality theory’s role in bridging the gap between non-convex analysis/mechanics and global optimization. With 18 total chapters written by experts in their fields, this volume provides a nonconventional theory for unified understanding of the fundamental difficulties in large deformation mechanics, bifurcation/chaos in nonlinear science, and the NP-hard problems in global optimization. Additionally, readers will find a unified methodology and powerful algorithms for solving challenging problems in comp...
Canonical Entropy and Phase Transition of Rotating Black Hole
International Nuclear Information System (INIS)
Ren, Zhao; Yue-Qin, Wu; Li-Chun, Zhang
2008-01-01
Recently, the Hawking radiation of a black hole has been studied using the tunnel effect method. The radiation spectrum of a black hole is derived. By discussing the correction to spectrum of the rotating black hole, we obtain the canonical entropy. The derived canonical entropy is equal to the sum of Bekenstein–Hawking entropy and correction term. The correction term near the critical point is different from the one near others. This difference plays an important role in studying the phase transition of the black hole. The black hole thermal capacity diverges at the critical point. However, the canonical entropy is not a complex number at this point. Thus we think that the phase transition created by this critical point is the second order phase transition. The discussed black hole is a five-dimensional Kerr-AdS black hole. We provide a basis for discussing thermodynamic properties of a higher-dimensional rotating black hole. (general)
QCD phase transition at real chemical potential with canonical approach
Energy Technology Data Exchange (ETDEWEB)
Nakamura, Atsushi [RCNP, Osaka University,Osaka, 567-0047 (Japan); Nishina Center, RIKEN,Wako, Saitama 351-0198 (Japan); School of Biomedicine, Far Eastern Federal University,Vladivostok, 690950 (Russian Federation); Oka, Shotaro [Institute of Theoretical Physics, Department of Physics, Rikkyo University,Toshima-ku, Tokyo 171-8501 (Japan); Taniguchi, Yusuke [Graduate School of Pure and Applied Sciences, University of Tsukuba,Tsukuba, Ibaraki 305-8571 (Japan)
2016-02-08
We study the finite density phase transition in the lattice QCD at real chemical potential. We adopt a canonical approach and the canonical partition function is constructed for N{sub f}=2 QCD. After derivation of the canonical partition function we calculate observables like the pressure, the quark number density, its second cumulant and the chiral condensate as a function of the real chemical potential. We covered a wide range of temperature region starting from the confining low to the deconfining high temperature; 0.65T{sub c}≤T≤3.62T{sub c}. We observe a possible signal of the deconfinement and the chiral restoration phase transition at real chemical potential below T{sub c} starting from the confining phase. We give also the convergence range of the fugacity expansion.
Canonical representations of the Lie superalgebra osp(1,4)
International Nuclear Information System (INIS)
Blank, J.; Havlicek, M.; Lassner, W.; Bednar, M.
1981-06-01
The method for constructing infinite dimensional representations of Lie superalgebras proposed by the authors recently is applied to the superalgebra osp(1,4). Explicit formulae for its generators in terms of two or three pairs of operators fulfilling the canonical commutation relations, at most one pair of operators fulfilling the canonical anticommutation relations and at most one real parameter are obtained. The generators of the Lie subalgebra sp(4,IR) contains osp(1,4) are represented skew-symmetrically and both Casimir operators are equal to multiples of the unity operator. (author)
Towards a conceptual history of canonization in totalitarian societies
DEFF Research Database (Denmark)
Postoutenko, Kirill
2016-01-01
a reference to his slogans and speeches. The article compares such a canonization in Soviet Union with parallel processes in Nazi Germany (where Adolf Hitler and his texts are revered to a much lesser degree) and United States of America (where this development is missing altogether despite Franklin D....... Roosevelt unprecedented media exposure). It turns out that Stalin’s discursive canonization has multiple reasons including his reliance on rigid radial networks of power and communication (as opposed to rotation of political and social roles in democracies), his interactional detachment from listeners and...
Canonical correlation analysis of course and teacher evaluation
DEFF Research Database (Denmark)
Sliusarenko, Tamara; Ersbøll, Bjarne Kjær
2010-01-01
At the Technical University of Denmark course evaluations are performed by the students on a questionnaire. On one form the students are asked specific questions regarding the course. On a second form they are asked specific questions about the teacher. This study investigates the extent to which...... information obtained from the course evaluation form overlaps with information obtained from the teacher evaluation form. Employing canonical correlation analysis it was found that course and teacher evaluations are correlated. However, the structure of the canonical correlation is subject to change...
Canonical extensions of the Johnson homomorphisms to the Torelli groupoid
DEFF Research Database (Denmark)
Bene, Alex; Kawazumi, Nariya; Penner, Robert
2009-01-01
We prove that every trivalent marked bordered fatgraph comes equipped with a canonical generalized Magnus expansion in the sense of Kawazumi. This Magnus expansion is used to give canonical extensions of the higher Johnson homomorphisms τm , for m 1 , to the Torelli groupoid, and we provide...... a recursive combinatorial formula for tensor representatives of these extensions. In particular, we give an explicit 1-cocycle in the dual fatgraph complex which extends τ2 and thus answer affirmatively a question of Morita and Penner. To illustrate our techniques for calculating higher Johnson homomorphisms...
A Nonlinear GMRES Optimization Algorithm for Canonical Tensor Decomposition
De Sterck, Hans
2011-01-01
A new algorithm is presented for computing a canonical rank-R tensor approximation that has minimal distance to a given tensor in the Frobenius norm, where the canonical rank-R tensor consists of the sum of R rank-one components. Each iteration of the method consists of three steps. In the first step, a tentative new iterate is generated by a stand-alone one-step process, for which we use alternating least squares (ALS). In the second step, an accelerated iterate is generated by a nonlinear g...
Structural Basis for the Canonical and Non-canonical PAM Recognition by CRISPR-Cpf1.
Yamano, Takashi; Zetsche, Bernd; Ishitani, Ryuichiro; Zhang, Feng; Nishimasu, Hiroshi; Nureki, Osamu
2017-08-17
The RNA-guided Cpf1 (also known as Cas12a) nuclease associates with a CRISPR RNA (crRNA) and cleaves the double-stranded DNA target complementary to the crRNA guide. The two Cpf1 orthologs from Acidaminococcus sp. (AsCpf1) and Lachnospiraceae bacterium (LbCpf1) have been harnessed for eukaryotic genome editing. Cpf1 requires a specific nucleotide sequence, called a protospacer adjacent motif (PAM), for target recognition. Besides the canonical TTTV PAM, Cpf1 recognizes suboptimal C-containing PAMs. Here, we report four crystal structures of LbCpf1 in complex with the crRNA and its target DNA containing either TTTA, TCTA, TCCA, or CCCA as the PAM. These structures revealed that, depending on the PAM sequences, LbCpf1 undergoes conformational changes to form altered interactions with the PAM-containing DNA duplexes, thereby achieving the relaxed PAM recognition. Collectively, the present structures advance our mechanistic understanding of the PAM-dependent, crRNA-guided DNA cleavage by the Cpf1 family nucleases. Copyright © 2017 Elsevier Inc. All rights reserved.
International Nuclear Information System (INIS)
Tipton, William W; Hennig, Richard G
2013-01-01
We present an evolutionary algorithm which predicts stable atomic structures and phase diagrams by searching the energy landscape of empirical and ab initio Hamiltonians. Composition and geometrical degrees of freedom may be varied simultaneously. We show that this method utilizes information from favorable local structure at one composition to predict that at others, achieving far greater efficiency of phase diagram prediction than a method which relies on sampling compositions individually. We detail this and a number of other efficiency-improving techniques implemented in the genetic algorithm for structure prediction code that is now publicly available. We test the efficiency of the software by searching the ternary Zr–Cu–Al system using an empirical embedded-atom model potential. In addition to testing the algorithm, we also evaluate the accuracy of the potential itself. We find that the potential stabilizes several correct ternary phases, while a few of the predicted ground states are unphysical. Our results suggest that genetic algorithm searches can be used to improve the methodology of empirical potential design. (paper)
Tipton, William W; Hennig, Richard G
2013-12-11
We present an evolutionary algorithm which predicts stable atomic structures and phase diagrams by searching the energy landscape of empirical and ab initio Hamiltonians. Composition and geometrical degrees of freedom may be varied simultaneously. We show that this method utilizes information from favorable local structure at one composition to predict that at others, achieving far greater efficiency of phase diagram prediction than a method which relies on sampling compositions individually. We detail this and a number of other efficiency-improving techniques implemented in the genetic algorithm for structure prediction code that is now publicly available. We test the efficiency of the software by searching the ternary Zr-Cu-Al system using an empirical embedded-atom model potential. In addition to testing the algorithm, we also evaluate the accuracy of the potential itself. We find that the potential stabilizes several correct ternary phases, while a few of the predicted ground states are unphysical. Our results suggest that genetic algorithm searches can be used to improve the methodology of empirical potential design.
Pool, René; Heringa, Jaap; Hoefling, Martin; Schulz, Roland; Smith, Jeremy C; Feenstra, K Anton
2012-01-01
We report on a python interface to the GROMACS molecular simulation package, GromPy (available at https://github.com/GromPy). This application programming interface (API) uses the ctypes python module that allows function calls to shared libraries, for example, written in C. To the best of our
Grand unification: quo vadis domine
International Nuclear Information System (INIS)
Senjanovic, G.
1985-01-01
The present theoretical and experimental situation with grand unification is summarized. The issues of proton decay and the Weinberg angle are addressed, going through the predictions of both the standard SU(5) theory and its supersymmetric extension. The SO(10) theory, which provides a minimal one family model, is then studied. The gravitational characteristics of domain walls and strings are then discussed. It is argued that there is a need to go beyond SO(10) in order to incorporate a unified picture of families. This leads to the prediction of mirror fermions, whose physics is analyzed. 31 refs
Graafikatriennaali grand prix Korea kunstnikule
1998-01-01
Tallinna XI graafikatriennaali rahvusvaheline žürii andis grand prix korea kunstnikule Chung¡Sang-Gonile, kolm võrdset preemiat - soome kunstnikele Anita Jensenile ja Tapani Mikkonenile ning jaapani kunstnikule Estuko Obatale. Eesti Kunstimuuseumi preemia - Wendy Swallow. Tallinna linna preemia ja Ivar Luki sponsoripreemia - Walter Jule. Sponsoripreemiad : Paletti Eesti AS preemia - Inga Heamägi; Rannila Profiili preemia - Mojca Zlokarnik; UNDP preemia - Andrea Juan. Rotermanni soolalao arhitektuuri- ja kunstikeskuse diplom - Lis Ingram, Heli Päivikki Kurunsaari, Randi Strand, Wendy Swallow
Grand Challenges of Enterprise Integration
Energy Technology Data Exchange (ETDEWEB)
Brosey, W.D; Neal, R.E.; Marks, D.
2001-04-01
Enterprise Integration connects and combines people, processes, systems, and technologies to ensure that the right people and the right processes have the right information and the right resources at the right time. A consensus roadmap for Technologies for Enterprise Integration was created as part of an industry/government/academia partnership in the Integrated Manufacturing Technology Initiative (IMTI). Two of the grand challenges identified by the roadmapping effort will be addressed here--Customer Responsive Enterprises and Totally Connected Enterprises. Each of these challenges is briefly discussed as to the current state of industry and the future vision as developed in the roadmap.
Grand Challenges for Environmental Magnetism
Verosub, K. L.
2009-05-01
The development of new, inexpensive, and rapid geochemical methods for determining the ages of geologic materials, their elemental composition, and their isotopic ratios over a broad array of elements puts into sharp focus the question: What information can environmental magnetic methods provide that can't be obtained using these other methods? Because iron is ubiquitous in the Earth's crust and because it exists in so many different forms, a discipline that looks in detail at iron-bearing minerals does have the potential to make significant contributions to the study of surficial processes. However, to reach that potential requires the development of new environmental magnetic methods. I would like to put forward three Grand Challenges for environmental magnetism that have the potential to move the field forward to a new level of scientific sophistication and that will allow environmental magnetists to compete successfully in a world increasingly dominated by geochemists. The first Grand Challenge is the development of new techniques that lead to the direct and unambiguous identification of the full suite of magnetic minerals. For many environmental magnetic applications, the key magnetic minerals are not just magnetite and hematite but also iron oxy-hydroxides (goethite, lepidocrocite, akaganeite, ferrihydrite), carbonates (siderite) and sulfides (pyrrhotite and greigite) as well as compounds involving iron and other transition metals (cobalt and nickel). The second Grand Challenge is the development of new analytical methods that provide specific quantitative values for the amount of each magnetic mineral present in a sample. One promising approach to this problem is the application of two- or three-component multivariate analysis to arrays of downcore environmental magnetic parameters. The third Grand Challenge is the development of new ways of determining, not just the average values, but the actual distributions of grain sizes and coercivities of each mineral
The Grand Challenges of Nanotechnology
International Nuclear Information System (INIS)
Lane, Neal
2001-01-01
Amazing breakthroughs and advances continue to be made in nanoscale science and engineering and the rapidly emerging field of nanotechnology, including near-commercial applications in biomedicine, computing and environmental protection. The National Nanotechnology Initiative, begun by the Clinton Administration has placed nanoscale research on a new funding trajectory. But, many 'grand challenges' must be overcome, technical ones as well as those related to funding, science and technology workforce, and the need for stronger collaboration across discipline, organizations, government agencies and with other countries
Grand Rounds in Pediatric Nephrology
African Journals Online (AJOL)
Centre for Kidney Research, The Children's Hospital at Westmead, Locked Bag 4001, ... Keywords nephrotic syndrome; infection; prednisolone; ... (urine protein on dipstick zero or trace) and cease. .... upper respiratory tract infection reduced the risk for relapse ... the most important predictor for kidney survival in SSNS is.
Connecting the Canon to Current Young Adult Literature
Rybakova, Katie; Roccanti, Rikki
2016-01-01
In this article we discuss the respective roles of young adult literature and literary texts in the secondary level English Language Arts classroom and explore the connections that can be made between popular young adult books and the traditional canon. We provide examples showing how young adult literature bestsellers such as "The Book…
Intermediate inflation from a non-canonical scalar field
Energy Technology Data Exchange (ETDEWEB)
Rezazadeh, K.; Karami, K. [Department of Physics, University of Kurdistan, Pasdaran St., Sanandaj (Iran, Islamic Republic of); Karimi, P., E-mail: rezazadeh86@gmail.com, E-mail: KKarami@uok.ac.ir, E-mail: parvin.karimi67@yahoo.com [Center for Excellence in Astronomy and Astrophysics (CEAA-RIAAM), P.O. Box 55134-441, Maragha (Iran, Islamic Republic of)
2015-09-01
We study the intermediate inflation in a non-canonical scalar field framework with a power-like Lagrangian. We show that in contrast with the standard canonical intermediate inflation, our non-canonical model is compatible with the observational results of Planck 2015. Also, we estimate the equilateral non-Gaussianity parameter which is in well agreement with the prediction of Planck 2015. Then, we obtain an approximation for the energy scale at the initial time of inflation and show that it can be of order of the Planck energy scale, i.e. M{sub P} ∼ 10{sup 18}GeV. We will see that after a short period of time, inflation enters in the slow-roll regime that its energy scale is of order M{sub P}/100 ∼ 10{sup 16}GeV and the horizon exit takes place in this energy scale. We also examine an idea in our non-canonical model to overcome the central drawback of intermediate inflation which is the fact that inflation never ends. We solve this problem without disturbing significantly the nature of the intermediate inflation until the time of horizon exit.
Comments on the charge-monopole canonical formalism
International Nuclear Information System (INIS)
Comay, C.
1988-01-01
A recently published canonical formalism of a charge-monopole system written by means of Clifford algebras is discussed. It is shown that the introduction of the Lorentz force must be accompanied by the removal of the pseudo-scalar terms from the lagrangian. Several conclusions follow. (orig.)
The roles of theory in canonical action research
Davison, R.M.; Martinsons, M.G.; Ou, C.X.J.
2012-01-01
Canonical action research (CAR) aims to address real-world problems and improve organizational performance by combining scholarly observations with practical interventions. However, efforts to conduct CAR have revealed challenges that reflect a significant research–practice gap. We examine these
Canonical realizations of B2 approximately C2 Lie algebras
International Nuclear Information System (INIS)
Iosifescu, M.; Scutaru, H.
1982-12-01
Canonical realizations associated to subrepresentations of ad x ad, for B 2 apppoximately C 2 semisimple Lie algebras, have been determined. An algebraic foundation has been obtained for the constraints satisfied by the dinamical variables of the classical limit of the generalized Helium problem. (authors)
Groups of automorphisms of the canonical commutation and anticommutation relations
International Nuclear Information System (INIS)
Grosse, H.; Pittner, L.
1987-01-01
Observables of supersymmetric quantum mechanics are coded by taking the antisymmetric tensor product with anticommuting parameters. Next we define superunitary transformations, which mix bosonic and fermionic degrees of freedom, in order to construct automorphisms of the canonical (anti-) commutation relations. Conversely, every automorphism of the C(A)CR is implemented by an essentially unique superunitary transformation. 12 refs. (Author)
Canonical understanding of the sacrifice of Isaac: The influence of ...
African Journals Online (AJOL)
2016-07-08
Jul 8, 2016 ... Martyrdom has granted benefits to the people of ... Testament, as the authoritative text and understands the text primarily in the canonical context ... This is more significant in terms of ..... This image of the Father-Son relation recurs in the NT, ..... this passage is Abraham's obedience, not Isaac's self-sacrifice.
Publication bias and the canonization of false facts
DEFF Research Database (Denmark)
Nissen, Silas Boye; Magidson, Tali; Gross, Kevin
2016-01-01
canonized as fact. Data-dredging, p-hacking, and similar behaviors exacerbate the problem. Should negative results become easier to publish as a claim approaches acceptance as a fact, however, true and false claims would be more readily distinguished. To the degree that the model reflects the real world...
The Meridians of Reference of Indian Astronomical Canons
Mercier, R.
The canons of Sanskrit astronomy depend on mean motions which are normally postulated to refer to the central meridian of Ujjain. The present work is a statistical analysis of these mean motions designed to discover the optimum position of the meridian, by comparison with modern mean motions. This follows earlier work done by Billard in determining the optimum year.
Gillers, Benjamin S.; Chiplunkar, Aditi; Aly, Haytham; Valenta, Tomas; Basler, Konrad; Christoffels, Vincent M.; Efimov, Igor R.; Boukens, Bastiaan J.; Rentschler, Stacey
2015-01-01
Proper patterning of the atrioventricular canal (AVC) is essential for delay of electrical impulses between atria and ventricles, and defects in AVC maturation can result in congenital heart disease. To determine the role of canonical Wnt signaling in the myocardium during AVC development. We used a
Canonical transformations and exact invariants for dissipative systems
International Nuclear Information System (INIS)
Pedrosa, I.A.
1986-01-01
A simple treatment to the problem of finding exact invariants and related auxiliary equations for time-dependent oscillators with friction is presented. The treatment is based on the use of a time-dependent canonical transformation and an auxiliary transformation. (Author) [pt
The Canon, the Web, and the Long Tail
DEFF Research Database (Denmark)
Sanderhoff, Merete
2017-01-01
This article argues that releasing images of artworks into the public domain creates a new possibility for the public to challenge the canon or create their own, based on access to previously inaccessible images. Through the dissemination of openly licensed artworks across the Internet, museums c...
Correspondence and canonicity in non-classical logic
Sourabh, S.
2015-01-01
In this thesis we study correspondence and canonicity for non-classical logic using algebraic and order-topological methods. Correspondence theory is aimed at answering the question of how precisely modal, first-order, second-order languages interact and overlap in their shared semantic environment.
A QQ→QQ planar double box in canonical form
Directory of Open Access Journals (Sweden)
Marco S. Bianchi
2018-02-01
Full Text Available We consider a planar double box with four massive external momenta and two massive internal propagators. We derive the system of differential equations for the relevant master integrals, cast it in canonical form, write it as a dlog form and solve it in terms of iterated integrals up to depth four.
A Problem-Centered Approach to Canonical Matrix Forms
Sylvestre, Jeremy
2014-01-01
This article outlines a problem-centered approach to the topic of canonical matrix forms in a second linear algebra course. In this approach, abstract theory, including such topics as eigenvalues, generalized eigenspaces, invariant subspaces, independent subspaces, nilpotency, and cyclic spaces, is developed in response to the patterns discovered…
Uncertainty relations, zero point energy and the linear canonical group
Sudarshan, E. C. G.
1993-01-01
The close relationship between the zero point energy, the uncertainty relations, coherent states, squeezed states, and correlated states for one mode is investigated. This group-theoretic perspective enables the parametrization and identification of their multimode generalization. In particular the generalized Schroedinger-Robertson uncertainty relations are analyzed. An elementary method of determining the canonical structure of the generalized correlated states is presented.
Nonlinear canonical correlation analysis with k sets of variables
van der Burg, Eeke; de Leeuw, Jan
1987-01-01
The multivariate technique OVERALS is introduced as a non-linear generalization of canonical correlation analysis (CCA). First, two sets CCA is introduced. Two sets CCA is a technique that computes linear combinations of sets of variables that correlate in an optimal way. Two sets CCA is then
Testing the significance of canonical axes in redundancy analysis
Legendre, P.; Oksanen, J.; Braak, ter C.J.F.
2011-01-01
1. Tests of significance of the individual canonical axes in redundancy analysis allow researchers to determine which of the axes represent variation that can be distinguished from random. Variation along the significant axes can be mapped, used to draw biplots or interpreted through subsequent
Canonical Ensemble Model for Black Hole Horizon of Schwarzschild ...
Indian Academy of Sciences (India)
Abstract. In this paper, we use the canonical ensemble model to discuss the radiation of a Schwarzschild–de Sitter black hole on the black hole horizon. Using this model, we calculate the probability distribution from function of the emission shell. And the statistical meaning which compare with the distribution function is ...
Non‐Canonical Replication Initiation: You’re Fired!
Directory of Open Access Journals (Sweden)
Bazilė Ravoitytė
2017-01-01
Full Text Available The division of prokaryotic and eukaryotic cells produces two cells that inherit a perfect copy of the genetic material originally derived from the mother cell. The initiation of canonical DNA replication must be coordinated to the cell cycle to ensure the accuracy of genome duplication. Controlled replication initiation depends on a complex interplay of cis‐acting DNA sequences, the so‐called origins of replication (ori, with trans‐acting factors involved in the onset of DNA synthesis. The interplay of cis‐acting elements and trans‐acting factors ensures that cells initiate replication at sequence‐specific sites only once, and in a timely order, to avoid chromosomal endoreplication. However, chromosome breakage and excessive RNA:DNA hybrid formation can cause breakinduced (BIR or transcription‐initiated replication (TIR, respectively. These non‐canonical replication events are expected to affect eukaryotic genome function and maintenance, and could be important for genome evolution and disease development. In this review, we describe the difference between canonical and non‐canonical DNA replication, and focus on mechanistic differences and common features between BIR and TIR. Finally, we discuss open issues on the factors and molecular mechanisms involved in TIR.
AFP Algorithm and a Canonical Normal Form for Horn Formulas
Majdoddin, Ruhollah
2014-01-01
AFP Algorithm is a learning algorithm for Horn formulas. We show that it does not improve the complexity of AFP Algorithm, if after each negative counterexample more that just one refinements are performed. Moreover, a canonical normal form for Horn formulas is presented, and it is proved that the output formula of AFP Algorithm is in this normal form.
Statistical hadronization and hadronic micro-canonical ensemble II
International Nuclear Information System (INIS)
Becattini, F.; Ferroni, L.
2004-01-01
We present a Monte Carlo calculation of the micro-canonical ensemble of the ideal hadron-resonance gas including all known states up to a mass of about 1.8 GeV and full quantum statistics. The micro-canonical average multiplicities of the various hadron species are found to converge to the canonical ones for moderately low values of the total energy, around 8 GeV, thus bearing out previous analyses of hadronic multiplicities in the canonical ensemble. The main numerical computing method is an importance sampling Monte Carlo algorithm using the product of Poisson distributions to generate multi-hadronic channels. It is shown that the use of this multi-Poisson distribution allows for an efficient and fast computation of averages, which can be further improved in the limit of very large clusters. We have also studied the fitness of a previously proposed computing method, based on the Metropolis Monte Carlo algorithm, for event generation in the statistical hadronization model. We find that the use of the multi-Poisson distribution as proposal matrix dramatically improves the computation performance. However, due to the correlation of subsequent samples, this method proves to be generally less robust and effective than the importance sampling method. (orig.)
Canonical analysis of non-relativistic particle and superparticle
Energy Technology Data Exchange (ETDEWEB)
Kluson, Josef [Masaryk University, Department of Theoretical Physics and Astrophysics, Faculty of Science, Brno (Czech Republic)
2018-02-15
We perform canonical analysis of non-relativistic particle in Newton-Cartan Background. Then we extend this analysis to the case of non-relativistic superparticle in the same background. We determine constraints structure of this theory and find generator of κ-symmetry. (orig.)
Canonical quantization of the Bateman-Morse-Feshbach damped oscillator
International Nuclear Information System (INIS)
Rideau, G.; Anderson, R.L.; Hebda, P.W.
1991-01-01
The Bateman-Morse-Feshbach classical formulation of the damped oscillator is canonically quantized. The spectrum of the Hamiltonian is given. It is shown that the wavefunctions behave asymptotically as a superposition of damped oscillators when their initial values belong to an appropriately-selected dense subset of the Hilbert space. (orig.)
Catechistic Teaching, National Canons, and the Regimentation of Students' Voice
Kroon, Sjaak
2013-01-01
Drawing on key incident analysis of classroom transcripts from Bashkortostan, France, North Korea, and Suriname, this article discusses the relationship between an increasingly canonical content of education and the discursive organization of teaching processes at the expense of both teachers' and students' voice. It argues that canonical…
Quasiperiodic canonical-cell tiling with pseudo icosahedral symmetry
Fujita, Nobuhisa
2017-10-01
Icosahedral quasicrystals and their approximants are generally described as packing of icosahedral clusters. Experimental studies show that clusters in various approximants are orderly arranged, such that their centers are located at the nodes (or vertices) of a periodic tiling composed of four basic polyhedra called the canonical cells. This so called canonical-cell geometry is likely to serve as a common framework for modeling how clusters are arranged in approximants, while its applicability seems to extend naturally to icosahedral quasicrystals. To date, however, it has not been proved yet if the canonical cells can tile the space quasiperiodically, though we usually believe that clusters in icosahedral quasicrystals are arranged such that quasiperiodic long-range order as well as icosahedral point symmetry is maintained. In this paper, we report for the first time an iterative geometrical transformation of the canonical cells defining a so-called substitution rule, which we can use to generate a class of quasiperiodic canonical-cell tilings. Every single step of the transformation proceeds as follows: each cell is first enlarged by a magnification ratio of τ3 (τ = golden mean) and then subdivided into cells of the original size. Here, cells with an identical shape can be subdivided in several distinct manners depending on how their adjacent neighbors are arranged, and sixteen types of cells are identified in terms of unique subdivision. This class of quasiperiodic canonical-cell tilings presents the first realization of three-dimensional quasiperiodic tilings with fractal atomic surfaces. There are four distinct atomic surfaces associated with four sub-modules of the primitive icosahedral module, where a representative of the four submodules corresponds to the Σ = 4 coincidence site module of the icosahedral module. It follows that the present quasiperiodic tilings involve a kind of superlattice ordering that manifests itself in satellite peaks in the
Management of pediatric radiation dose using Canon digital radiography
International Nuclear Information System (INIS)
Arreola, M.; Rill, L.
2004-01-01
A Canon CXDI-11 digital radiography (DR) system has been in use at Shands Hospital at the University of Florida for the past 2 1/2 years. A first clinical implementation phase was utilized to develop imaging protocols for adult patients, with a second phase incorporating pediatric chest and abdominal studies a few months later. This paper describes some of the steps taken during the modality implementation stages, as well as the methodologies and procedures utilized to monitor compliance by the technologists. The Canon DR system provides the technologist with an indication of the radiation exposure received by the detector (and thus of the patient dose) by means of an indirect exposure level number called the reached exposure (REX) value. The REX value is calculated by the system based on the default grayscale curve preselected for a given anatomical view and used by the system to optimize the appearance of the image. The brightness and contrast of the image can be modified by the user at the QC/control screen for the purpose of improving the appearance of the image. Such changes modify the actual grayscale curve (position and slope, respectively) and thus the calculated REX value. Thus, undisciplined use of the brightness and contrast functions by the technologist can render the REX value meaningless as an exposure indicator. The paper also shows how it is possible to calibrate AEC (phototimer) systems for use with the Canon DR system, and utilize the REX value as a valuable dose indicator through proper training of technologists and strict, disciplined QC of studies. A team consisting of the site's medical physicist, radiologists, and technologists, as well as Canon engineers, can work together in properly calibrating and setting up the system for the purposes of monitoring patient doses (especially pediatric) in DR studies performed in a Canon DR system. (orig.)
Karmakar, Partha; Das, Pradip Kumar; Mondal, Seema Sarkar; Karmakar, Sougata; Mazumdar, Debasis
2010-10-01
Pb pollution from automobile exhausts around highways is a persistent problem in India. Pb intoxication in mammalian body is a complex phenomenon which is influence by agonistic and antagonistic interactions of several other heavy metals and micronutrients. An attempt has been made to study the association between Pb and Zn accumulation in different physiological systems of cattles (n = 200) by application of both canonical correlation and canonical correspondence analyses. Pb was estimated from plasma, liver, bone, muscle, kidney, blood and milk where as Zn was measured from all these systems except bone, blood and milk. Both statistical techniques demonstrated that there was a strong association among blood-Pb, liver-Zn, kidney-Zn and muscle-Zn. From observations, it can be assumed that Zn accumulation in cattles' muscle, liver and kidney directs Pb mobilization from those organs which in turn increases Pb pool in blood. It indicates antagonistic activity of Zn to the accumulation of Pb. Although there were some contradictions between the observations obtained from the two different statistical methods, the overall pattern of Pb accumulation in various organs as influenced by Zn were same. It is mainly due to the fact that canonical correlation is actually a special type of canonical correspondence analyses where linear relationship is followed between two groups of variables instead of Gaussian relationship.
International Nuclear Information System (INIS)
Karmakar, Partha; Das, Pradip Kumar; Mondal, Seema Sarkar; Karmakar, Sougata; Mazumdar, Debasis
2010-01-01
Pb pollution from automobile exhausts around highways is a persistent problem in India. Pb intoxication in mammalian body is a complex phenomenon which is influence by agonistic and antagonistic interactions of several other heavy metals and micronutrients. An attempt has been made to study the association between Pb and Zn accumulation in different physiological systems of cattles (n = 200) by application of both canonical correlation and canonical correspondence analyses. Pb was estimated from plasma, liver, bone, muscle, kidney, blood and milk where as Zn was measured from all these systems except bone, blood and milk. Both statistical techniques demonstrated that there was a strong association among blood-Pb, liver-Zn, kidney-Zn and muscle-Zn. From observations, it can be assumed that Zn accumulation in cattles' muscle, liver and kidney directs Pb mobilization from those organs which in turn increases Pb pool in blood. It indicates antagonistic activity of Zn to the accumulation of Pb. Although there were some contradictions between the observations obtained from the two different statistical methods, the overall pattern of Pb accumulation in various organs as influenced by Zn were same. It is mainly due to the fact that canonical correlation is actually a special type of canonical correspondence analyses where linear relationship is followed between two groups of variables instead of Gaussian relationship.
Canonical and Non-Canonical NF-κB Signaling Promotes Breast Cancer Tumor-Initiating Cells
Kendellen, Megan F.; Bradford, Jennifer W.; Lawrence, Cortney L.; Clark, Kelly S.; Baldwin, Albert S.
2014-01-01
Tumor-initiating cells (TICs) are a sub-population of cells that exhibit a robust ability to self-renew and contribute to the formation of primary tumors, the relapse of previously treated tumors, and the development of metastases. TICs have been identified in various tumors, including those of the breast, and are particularly enriched in the basal-like and claudin-low subtypes of breast cancer. The signaling pathways that contribute to the function and maintenance of TICs are under intense study. We explored the potential involvement of the NF-κB family of transcription factors in TICs in cell lines that are representative of basal-like and claudin-low breast cancer. NF-κB was found to be activated in breast cancer cells that form tumorspheres efficiently. Moreover, both canonical and non-canonical NF-κB signaling is required for these cells to self-renew in vitro and to form xenograft tumors efficiently in vivo using limiting dilutions of cells. Consistent with this, canonical and non-canonical NF-κB signaling is activated in TICs isolated from breast cancer cell lines. Experimental results indicate that NF-κB promotes the function of TICs by stimulating epithelial-to-mesenchymal transition (EMT) and by upregulating the expression of the inflammatory cytokines IL-1β and IL-6. The results suggest the use of NF-κB inhibitors for clinical therapy of certain breast cancers. PMID:23474754
Next Generation Innovation Policy and Grand Challenges
Kuhlmann, Stefan; Rip, Arie
2018-01-01
The paper explores transformative ways to address Grand Challenges, while locating them in a broader diagnosis of ongoing changes. Coping with Grand Challenges is a challenge in its own right, for policy as well as for science, technology, and innovation actors. The paper presents building blocks
Proton hexality in local grand unification
Energy Technology Data Exchange (ETDEWEB)
Foerste, Stefan; Nilles, Hans Peter [Bonn Univ. (Germany). Bethe Center for Theoretical Physics and Physikalisches Institut; Ramos-Sanchez, Saul [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Vaudrevange, Patrick K.S. [Muenchen Univ. (Germany). Arnold Sommerfeld Center for Theoretical Physics
2010-07-15
Proton hexality is a discrete symmetry that avoids the problem of too fast proton decay in the supersymmetric extension of the standard model. Unfortunately it is inconsistent with conventional grand unification. We show that proton hexality can be incorporated in the scheme of ''Local Grand Unification'' discussed in the framework of model building in (heterotic) string theory. (orig.)
Climate Prediction Center(CPC)Ensemble Canonical Correlation Analysis Forecast of Temperature
National Oceanic and Atmospheric Administration, Department of Commerce — The Ensemble Canonical Correlation Analysis (ECCA) temperature forecast is a 90-day (seasonal) outlook of US surface temperature anomalies. The ECCA uses Canonical...
Canonical sound speed profile and related ray acoustic parameters in the Bay of Bengal
Digital Repository Service at National Institute of Oceanography (India)
Murty, T.V.R.; Sadhuram, Y.; Rao, M.M.M.; Rao, B.P.; SuryaPrakash, S.; Chandramouli, P.; Murthy, K.S.R.; Prasad, K.V.S.R.
Following Munk's canonical theory, canonical parameters (i.e., B the stratification scale and epsilon the perturbation coefficient) in adiabatic ocean are obtained using SOFAR channel parameters (i.e., C sound velocity at the channel axis, Z sub(1...
Statistical analysis of aerosol species, trace gasses, and meteorology in Chicago.
Binaku, Katrina; O'Brien, Timothy; Schmeling, Martina; Fosco, Tinamarie
2013-09-01
Both canonical correlation analysis (CCA) and principal component analysis (PCA) were applied to atmospheric aerosol and trace gas concentrations and meteorological data collected in Chicago during the summer months of 2002, 2003, and 2004. Concentrations of ammonium, calcium, nitrate, sulfate, and oxalate particulate matter, as well as, meteorological parameters temperature, wind speed, wind direction, and humidity were subjected to CCA and PCA. Ozone and nitrogen oxide mixing ratios were also included in the data set. The purpose of statistical analysis was to determine the extent of existing linear relationship(s), or lack thereof, between meteorological parameters and pollutant concentrations in addition to reducing dimensionality of the original data to determine sources of pollutants. In CCA, the first three canonical variate pairs derived were statistically significant at the 0.05 level. Canonical correlation between the first canonical variate pair was 0.821, while correlations of the second and third canonical variate pairs were 0.562 and 0.461, respectively. The first canonical variate pair indicated that increasing temperatures resulted in high ozone mixing ratios, while the second canonical variate pair showed wind speed and humidity's influence on local ammonium concentrations. No new information was uncovered in the third variate pair. Canonical loadings were also interpreted for information regarding relationships between data sets. Four principal components (PCs), expressing 77.0 % of original data variance, were derived in PCA. Interpretation of PCs suggested significant production and/or transport of secondary aerosols in the region (PC1). Furthermore, photochemical production of ozone and wind speed's influence on pollutants were expressed (PC2) along with overall measure of local meteorology (PC3). In summary, CCA and PCA results combined were successful in uncovering linear relationships between meteorology and air pollutants in Chicago and
Geochemical investigation of UMTRAP designated site at Grand Junction, Colorado
International Nuclear Information System (INIS)
Markos, G.; Bush, K.J.
1983-09-01
This report is the result of a geochemical investigation of the former uranium mill and tailings site at Grand Junction, Colorado. The objectives of the investigation are to characterize the geochemistry, to determine the contaminant distribution resulting from the former milling activities and tailings, and to infer chemical pathways and transport mechanisms from the contaminant distribution. The results should be used to model contaminant migration and to develop criteria for long-term containment media, such as a cover system which is impermeable to contaminant migration. This report assumes a familiarity with the hydrologic conditions of the site and the geochemical concepts underlying the investigation. The results reported are based on a sampling of waters in two seasons and solid material from the background, the area adjacent to the site, and the site. The solid samples were water extracted to remove easily soluble salts and acid extracted to remove carbonates and hydroxides. The water extracts and solid samples were analyzed for the major and trace elements. A limited number of samples were analyzed for radiological components. The report includes the methods of sampling, sample processing, analysis, and data interpretation. Four major conclusions are: (1) trace element concentrations in shallow subsurface waters adjacent to the tailings temporally vary up to an order of magnitude; (2) the riverbank soils and borehole waters are contaminated with uranium, radium, and trace elements from discharge of tailings solids and solutions during the active time of the mill; however, the movement of contaminants toward the Colorado River does not appear to be significant; (3) the Colorado River adjacent to the tailings is not contaminated; and (4) trace metals have accumulated at both the tailings/cover and tailings/soil interface because of precipitation reactions caused by chemical differences between the two materials
Probing the canonicity of the Wnt/Wingless signaling pathway.
Directory of Open Access Journals (Sweden)
Alexandra Franz
2017-04-01
Full Text Available The hallmark of canonical Wnt signaling is the transcriptional induction of Wnt target genes by the beta-catenin/TCF complex. Several studies have proposed alternative interaction partners for beta-catenin or TCF, but the relevance of potential bifurcations in the distal Wnt pathway remains unclear. Here we study on a genome-wide scale the requirement for Armadillo (Arm, Drosophila beta-catenin and Pangolin (Pan, Drosophila TCF in the Wnt/Wingless(Wg-induced transcriptional response of Drosophila Kc cells. Using somatic genetics, we demonstrate that both Arm and Pan are absolutely required for mediating activation and repression of target genes. Furthermore, by means of STARR-sequencing we identified Wnt/Wg-responsive enhancer elements and found that all responsive enhancers depend on Pan. Together, our results confirm the dogma of canonical Wnt/Wg signaling and argue against the existence of distal pathway branches in this system.
A canonical correlation neural network for multicollinearity and functional data.
Gou, Zhenkun; Fyfe, Colin
2004-03-01
We review a recent neural implementation of Canonical Correlation Analysis and show, using ideas suggested by Ridge Regression, how to make the algorithm robust. The network is shown to operate on data sets which exhibit multicollinearity. We develop a second model which not only performs as well on multicollinear data but also on general data sets. This model allows us to vary a single parameter so that the network is capable of performing Partial Least Squares regression (at one extreme) to Canonical Correlation Analysis (at the other)and every intermediate operation between the two. On multicollinear data, the parameter setting is shown to be important but on more general data no particular parameter setting is required. Finally, we develop a second penalty term which acts on such data as a smoother in that the resulting weight vectors are much smoother and more interpretable than the weights without the robustification term. We illustrate our algorithms on both artificial and real data.
Canonical form of Euler-Lagrange equations and gauge symmetries
Energy Technology Data Exchange (ETDEWEB)
Geyer, B [Naturwissenschaftlich-Theoretisches Zentrum und Institut fuer Theoretische Physik, Universitaet Leipzig, Leipzig (Germany); Gitman, D M [Institute of Physics, University of Sao Paulo, Sao Paulo (Brazil); Tyutin, I V [Lebedev Physics Institute, Moscow (Russian Federation)
2003-06-13
The structure of the Euler-Lagrange equations for a general Lagrangian theory (e.g. singular, with higher derivatives) is studied. For these equations we present a reduction procedure to the so-called canonical form. In the canonical form the equations are solved with respect to highest-order derivatives of nongauge coordinates, whereas gauge coordinates and their derivatives enter the right-hand sides of the equations as arbitrary functions of time. The reduction procedure reveals constraints in the Lagrangian formulation of singular systems and, in that respect, is similar to the Dirac procedure in the Hamiltonian formulation. Moreover, the reduction procedure allows one to reveal the gauge identities between the Euler-Lagrange equations. Thus, a constructive way of finding all the gauge generators within the Lagrangian formulation is presented. At the same time, it is proved that for local theories all the gauge generators are local in time operators.
Application of Canonical Effective Methods to Background-Independent Theories
Buyukcam, Umut
Effective formalisms play an important role in analyzing phenomena above some given length scale when complete theories are not accessible. In diverse exotic but physically important cases, the usual path-integral techniques used in a standard Quantum Field Theory approach seldom serve as adequate tools. This thesis exposes a new effective method for quantum systems, called the Canonical Effective Method, which owns particularly wide applicability in backgroundindependent theories as in the case of gravitational phenomena. The central purpose of this work is to employ these techniques to obtain semi-classical dynamics from canonical quantum gravity theories. Application to non-associative quantum mechanics is developed and testable results are obtained. Types of non-associative algebras relevant for magnetic-monopole systems are discussed. Possible modifications of hypersurface deformation algebra and the emergence of effective space-times are presented. iii.
Geometry of real and complex canonical transformations in quantum mechanics
International Nuclear Information System (INIS)
Grossmann, A.
1977-08-01
Quantum mechanics of finitely many particles involves the group of linear (and affine) canonical transformations. A well-defined ray representation of this group acts in the space of states of any quantum-mechanical system with finitely many degrees of freedom and plays a central role in many different contexts. This representation appears quite naturally in quantum mechanics over phase space (Weyl-Wigner correspondence), that it becomes, when suitably written, just a matter of looking at one object from different symplectic reference frames. This is particularly interesting for complex canonical transformations which are represented by unbounded operators. The list of references gives an idea of the variety of motivations and points of view in the subject
Magnetic phase diagrams from non-collinear canonical band theory
DEFF Research Database (Denmark)
Shallcross, Sam; Nordstrom, L.; Sharma, S.
2007-01-01
A canonical band theory of non-collinear magnetism is developed and applied to the close packed fcc and bcc crystal structures. This is a parameter-free theory where the crystal and magnetic symmetry and exchange splitting uniquely determine the electronic bands. In this way, we are able...... hybridization, and on this basis we are able to analyze the microscopic reasons behind the occurrence of non-collinear magnetism in the elemental itinerant magnets....... to construct phase diagrams of magnetic order for the fcc and bcc lattices. Several examples of non-collinear magnetism are seen to be canonical in origin, in particular, that of gamma-Fe. In this approach, the determination of magnetic stability results solely from changes in kinetic energy due to spin...
Some reference formulas for the generating functions of canonical transformations
Energy Technology Data Exchange (ETDEWEB)
Anselmi, Damiano [Universita di Pisa, Dipartimento di Fisica ' ' Enrico Fermi' ' , Pisa (Italy); INFN, Sezione di Pisa, Pisa (Italy)
2016-02-15
We study some properties of the canonical transformations in classical mechanics and quantum field theory and give a number of practical formulas concerning their generating functions. First, we give a diagrammatic formula for the perturbative expansion of the composition law around the identity map. Then we propose a standard way to express the generating function of a canonical transformation by means of a certain ''componential'' map, which obeys the Baker-Campbell-Hausdorff formula. We derive the diagrammatic interpretation of the componential map, work out its relation with the solution of the Hamilton-Jacobi equation and derive its time-ordered version. Finally, we generalize the results to the Batalin-Vilkovisky formalism, where the conjugate variables may have both bosonic and fermionic statistics, and describe applications to quantum field theory. (orig.)
Lorentz covariant canonical symplectic algorithms for dynamics of charged particles
Wang, Yulei; Liu, Jian; Qin, Hong
2016-12-01
In this paper, the Lorentz covariance of algorithms is introduced. Under Lorentz transformation, both the form and performance of a Lorentz covariant algorithm are invariant. To acquire the advantages of symplectic algorithms and Lorentz covariance, a general procedure for constructing Lorentz covariant canonical symplectic algorithms (LCCSAs) is provided, based on which an explicit LCCSA for dynamics of relativistic charged particles is built. LCCSA possesses Lorentz invariance as well as long-term numerical accuracy and stability, due to the preservation of a discrete symplectic structure and the Lorentz symmetry of the system. For situations with time-dependent electromagnetic fields, which are difficult to handle in traditional construction procedures of symplectic algorithms, LCCSA provides a perfect explicit canonical symplectic solution by implementing the discretization in 4-spacetime. We also show that LCCSA has built-in energy-based adaptive time steps, which can optimize the computation performance when the Lorentz factor varies.
A Top-Down Account of Linear Canonical Transforms
Directory of Open Access Journals (Sweden)
Kurt Bernardo Wolf
2012-06-01
Full Text Available We contend that what are called Linear Canonical Transforms (LCTs should be seen as a part of the theory of unitary irreducible representations of the '2+1' Lorentz group. The integral kernel representation found by Collins, Moshinsky and Quesne, and the radial and hyperbolic LCTs introduced thereafter, belong to the discrete and continuous representation series of the Lorentz group in its parabolic subgroup reduction. The reduction by the elliptic and hyperbolic subgroups can also be considered to yield LCTs that act on functions, discrete or continuous in other Hilbert spaces. We gather the summation and integration kernels reported by Basu and Wolf when studiying all discrete, continuous, and mixed representations of the linear group of 2×2 real matrices. We add some comments on why all should be considered canonical.
Common activation of canonical Wnt signaling in pancreatic adenocarcinoma.
Directory of Open Access Journals (Sweden)
Marina Pasca di Magliano
2007-11-01
Full Text Available Pancreatic ductal adenocarcinoma (PDA is an extremely aggressive malignancy, which carries a dismal prognosis. Activating mutations of the Kras gene are common to the vast majority of human PDA. In addition, recent studies have demonstrated that embryonic signaling pathway such as Hedgehog and Notch are inappropriately upregulated in this disease. The role of another embryonic signaling pathway, namely the canonical Wnt cascade, is still controversial. Here, we use gene array analysis as a platform to demonstrate general activation of the canonical arm of the Wnt pathway in human PDA. Furthermore, we provide evidence for Wnt activation in mouse models of pancreatic cancer. Our results also indicate that Wnt signaling might be activated downstream of Hedgehog signaling, which is an early event in PDA evolution. Wnt inhibition blocked proliferation and induced apoptosis of cultured adenocarcinoma cells, thereby providing evidence to support the development of novel therapeutical strategies for Wnt inhibition in pancreatic adenocarcinoma.
Canonical Drude Weight for Non-integrable Quantum Spin Chains
Mastropietro, Vieri; Porta, Marcello
2018-03-01
The Drude weight is a central quantity for the transport properties of quantum spin chains. The canonical definition of Drude weight is directly related to Kubo formula of conductivity. However, the difficulty in the evaluation of such expression has led to several alternative formulations, accessible to different methods. In particular, the Euclidean, or imaginary-time, Drude weight can be studied via rigorous renormalization group. As a result, in the past years several universality results have been proven for such quantity at zero temperature; remarkably, the proofs work for both integrable and non-integrable quantum spin chains. Here we establish the equivalence of Euclidean and canonical Drude weights at zero temperature. Our proof is based on rigorous renormalization group methods, Ward identities, and complex analytic ideas.
Baryon number violation and novel canonical anti-commutation relations
Fujikawa, Kazuo; Tureanu, Anca
2018-02-01
The possible neutron-antineutron oscillation is described by an effective quadratic Lagrangian analogous to the BCS theory. It is shown that the conventional equal-time anti-commutation relations of the neutron variable n (t , x →) are modified by the baryon number violating terms. This is established by the Bjorken-Johnson-Low prescription and also by the canonical quantization combined with equations of motion. This novel canonical behavior can give rise to an important physical effect, which is illustrated by analyzing the Lagrangian that violates the baryon number but gives rise to the degenerate effective Majorana fermions and thus no neutron-antineutron oscillation. Technically, this model is neatly treated using a relativistic analogue of the Bogoliubov transformation.
Partitioned Alternating Least Squares Technique for Canonical Polyadic Tensor Decomposition
Czech Academy of Sciences Publication Activity Database
Tichavský, Petr; Phan, A. H.; Cichocki, A.
2016-01-01
Roč. 23, č. 7 (2016), s. 993-997 ISSN 1070-9908 R&D Projects: GA ČR(CZ) GA14-13713S Institutional support: RVO:67985556 Keywords : canonical polyadic decomposition * PARAFAC * tensor decomposition Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 2.528, year: 2016 http://library.utia.cas.cz/separaty/2016/SI/tichavsky-0460710.pdf
Null canonical formalism 1, Maxwell field. [Poisson brackets, boundary conditions
Energy Technology Data Exchange (ETDEWEB)
Wodkiewicz, K [Warsaw Univ. (Poland). Inst. Fizyki Teoretycznej
1975-01-01
The purpose of this paper is to formulate the canonical formalism on null hypersurfaces for the Maxwell electrodynamics. The set of the Poisson brackets relations for null variables of the Maxwell field is obtained. The asymptotic properties of the theory are investigated. The Poisson bracket relations for the news-functions of the Maxwell field are computed. The Hamiltonian form of the asymptotic Maxwell equations in terms of these news-functions is obtained.
Canonical Ensemble Model for Black Hole Radiation Jingyi Zhang
Indian Academy of Sciences (India)
Canonical Ensemble Model for Black Hole Radiation. 575. For entropy, there is no corresponding thermodynamical quantity, without loss of generalization. Let us define an entropy operator. ˆS = −KB ln ˆρ. (11). Then, the mean value of entropy is. S ≡〈ˆS〉 = tr( ˆρ ˆS) = −KBtr( ˆρ ln ˆρ). (12). For ideal gases, let y = V , then the ...
Completion is an Instance of Abstract Canonical System Inference
Burel , Guillaume; Kirchner , Claude
2006-01-01
http://www.springerlink.com/content/u222753gl333221p/; Abstract canonical systems and inference (ACSI) were introduced to formalize the intuitive notions of good proof and good inference appearing typically in first-order logic or in Knuth-Bendix like completion procedures. Since this abstract framework is intended to be generic, it is of fundamental interest to show its adequacy to represent the main systems of interest. This has been done for ground completion (where all equational axioms a...
Canonical action-angle formalism for quantized nonlinear fields
International Nuclear Information System (INIS)
Garbaczewki, P.
1987-01-01
The canonical quantizations of field and action-angle coordinates which (locally) parameterize the phase manifold for the same nonlinear field theory model (e.g. sine-Gordon and nonlinear Schrodinger with the attractive coupling) are reconciled on the common for both cases state space. The classical-quantum relationship is maintained in the mean: coherent state expectation values of operators give rise to classical objects
Canonical quantum theory of gravitational field with higher derivatives, 2
International Nuclear Information System (INIS)
Kawasaki, Shoichiro; Kimura, Tadahiko
1982-01-01
The asymptotic fields in a canonically quantized graviational field with higher derivatives are analyzed. A possible mechanism of the recovery of the physical S-matrix unitarity is discussed. The constraint nabla sub(μ)(B sup(μν) + (Beta /α)g sup(μν)B) = 0 due to the Bianchi identity on R sub(μν) is treated by Dirac's method. (author)
Canonical quantum theory of gravitational field with higher derivatives
International Nuclear Information System (INIS)
Kawasaki, Shoichiro; Kimura, Tadahiko; Kitago, Koichi.
1981-01-01
A renormalizable gravitational theory with higher derivatives is canonically quantized in the Landau gauge. Field equations and various equal-time commutation relations are explicitly given. The main results obtained in this work are 1) the equal-time commutation relations involving b sub(μ) exhibit the tensor-like behaviour and 2) the theory has the 16-dimensional Poincare-like superalgebra. These results are just the same as those discovered by Nakanishi in the Einstein case. (author)
Canons, competencies and critique: delivering an undergraduate entrepreneurial marketing module
Ardley, Barry; Hardwick, Jialin
2017-01-01
In the context of the debate about the status of marketing degrees, graduate knowledge and competencies, this paper reflects on a set of pedagogic issues associated with the delivery of a final level entrepreneurial marketing module. Drawing on key literature, the module takes a set of entrepreneurial marketing canons as the basis of learning. Primary research was conducted into student perceptions of the module based on an interpretative methodology, using an open ended questionnaire. Studen...
Optimization via separated representations and the canonical tensor decomposition
Reynolds, Matthew J.; Beylkin, Gregory; Doostan, Alireza
2017-11-01
We introduce a new, quadratically convergent algorithm for finding maximum absolute value entries of tensors represented in the canonical format. The computational complexity of the algorithm is linear in the dimension of the tensor. We show how to use this algorithm to find global maxima of non-convex multivariate functions in separated form. We demonstrate the performance of the new algorithms on several examples.
Lattice QCD at finite density via a new canonical approach
International Nuclear Information System (INIS)
Alexandru, Andrei; Horvath, Ivan; Liu, K.-F.; Faber, Manfried
2005-01-01
We carry out a finite density calculation based on a canonical approach which is designed to address the overlap problem. Two degenerate flavor simulations are performed using Wilson gauge action and Wilson fermions on 4 4 lattices, at temperatures close to the critical temperature T c ≅170 MeV and large densities (5 to 20 times nuclear matter density). In this region, we find that the algorithm works well. We compare our results with those from other approaches
Optimization via Separated Representations and the Canonical Tensor Decomposition
Reynolds, Matthew J; Beylkin, Gregory; Doostan, Alireza
2016-01-01
We introduce a new, quadratically convergent algorithm for finding maximum absolute value entries of tensors represented in the canonical format. The computational complexity of the algorithm is linear in the dimension of the tensor. We show how to use this algorithm to find global maxima of non-convex multivariate functions in separated form. We demonstrate the performance of the new algorithms on several examples.
Canonical perturbation theory in linearized general relativity theory
International Nuclear Information System (INIS)
Gonzales, R.; Pavlenko, Yu.G.
1986-01-01
Canonical perturbation theory in linearized general relativity theory is developed. It is shown that the evolution of arbitrary dynamic value, conditioned by the interaction of particles, gravitation and electromagnetic fields, can be presented in the form of a series, each member of it corresponding to the contribution of certain spontaneous or induced process. The main concepts of the approach are presented in the approximation of a weak gravitational field
Deformations in closed string theory: canonical formulation and regularization
International Nuclear Information System (INIS)
Cederwall, M.; Von Gussich, A.; Sundell, P.
1996-01-01
We study deformations of closed string theory by primary fields of conformal weight (1,1), using conformal techniques on the complex plane. A canonical surface integral formalism for computing commutators in a non-holomorphic theory is constructed, and explicit formulae for deformations of operators are given. We identify the unique regularization of the arising divergences that respects conformal invariance, and consider the corresponding parallel transport. The associated connection is metric compatible and carries no curvature. (orig.)
Interactive Stable Ray Tracing
DEFF Research Database (Denmark)
Dal Corso, Alessandro; Salvi, Marco; Kolb, Craig
2017-01-01
Interactive ray tracing applications running on commodity hardware can suffer from objectionable temporal artifacts due to a low sample count. We introduce stable ray tracing, a technique that improves temporal stability without the over-blurring and ghosting artifacts typical of temporal post-pr...
Canonical quantization of so-called non-Lagrangian systems
Energy Technology Data Exchange (ETDEWEB)
Gitman, D.M. [Universidade de Sao Paulo, Instituto de Fisica, Caixa Postal 66318-CEP, Sao Paulo, S.P. (Brazil); Kupriyanov, V.G. [Universidade de Sao Paulo, Instituto de Fisica, Caixa Postal 66318-CEP, Sao Paulo, S.P. (Brazil); Tomsk State University, Physics Department, Tomsk (Russian Federation)
2007-04-15
We present an approach to the canonical quantization of systems with equations of motion that are historically called non-Lagrangian equations. Our viewpoint of this problem is the following: despite the fact that a set of differential equations cannot be directly identified with a set of Euler-Lagrange equations, one can reformulate such a set in an equivalent first-order form that can always be treated as the Euler-Lagrange equations of a certain action. We construct such an action explicitly. It turns out that in the general case the hamiltonization and canonical quantization of such an action are non-trivial problems, since the theory involves time-dependent constraints. We adopt the general approach of hamiltonization and canonical quantization for such theories as described in D.M. Gitman, I.V. Tyutin, Quantization of Fields with Constraints (Springer, Berlin, 1990). to the case under consideration. There exists an ambiguity (that cannot be reduced to the addition of a total time derivative) in associating a Lagrange function with a given set of equations. We present a complete description of this ambiguity. The proposed scheme is applied to the quantization of a general quadratic theory. In addition, we consider the quantization of a damped oscillator and of a radiating point-like charge. (orig.)
Canonical quantization of so-called non-Lagrangian systems
International Nuclear Information System (INIS)
Gitman, D.M.; Kupriyanov, V.G.
2007-01-01
We present an approach to the canonical quantization of systems with equations of motion that are historically called non-Lagrangian equations. Our viewpoint of this problem is the following: despite the fact that a set of differential equations cannot be directly identified with a set of Euler-Lagrange equations, one can reformulate such a set in an equivalent first-order form that can always be treated as the Euler-Lagrange equations of a certain action. We construct such an action explicitly. It turns out that in the general case the hamiltonization and canonical quantization of such an action are non-trivial problems, since the theory involves time-dependent constraints. We adopt the general approach of hamiltonization and canonical quantization for such theories as described in D.M. Gitman, I.V. Tyutin, Quantization of Fields with Constraints (Springer, Berlin, 1990). to the case under consideration. There exists an ambiguity (that cannot be reduced to the addition of a total time derivative) in associating a Lagrange function with a given set of equations. We present a complete description of this ambiguity. The proposed scheme is applied to the quantization of a general quadratic theory. In addition, we consider the quantization of a damped oscillator and of a radiating point-like charge. (orig.)
A Canonical Theory of Dynamic Decision-Making
Fox, John; Cooper, Richard P.; Glasspool, David W.
2012-01-01
Decision-making behavior is studied in many very different fields, from medicine and economics to psychology and neuroscience, with major contributions from mathematics and statistics, computer science, AI, and other technical disciplines. However the conceptualization of what decision-making is and methods for studying it vary greatly and this has resulted in fragmentation of the field. A theory that can accommodate various perspectives may facilitate interdisciplinary working. We present such a theory in which decision-making is articulated as a set of canonical functions that are sufficiently general to accommodate diverse viewpoints, yet sufficiently precise that they can be instantiated in different ways for specific theoretical or practical purposes. The canons cover the whole decision cycle, from the framing of a decision based on the goals, beliefs, and background knowledge of the decision-maker to the formulation of decision options, establishing preferences over them, and making commitments. Commitments can lead to the initiation of new decisions and any step in the cycle can incorporate reasoning about previous decisions and the rationales for them, and lead to revising or abandoning existing commitments. The theory situates decision-making with respect to other high-level cognitive capabilities like problem solving, planning, and collaborative decision-making. The canonical approach is assessed in three domains: cognitive and neuropsychology, artificial intelligence, and decision engineering. PMID:23565100
Non-Canonical Cell Death Induced by p53
Directory of Open Access Journals (Sweden)
Atul Ranjan
2016-12-01
Full Text Available Programmed cell death is a vital biological process for multicellular organisms to maintain cellular homeostasis, which is regulated in a complex manner. Over the past several years, apart from apoptosis, which is the principal mechanism of caspase-dependent cell death, research on non-apoptotic forms of programmed cell death has gained momentum. p53 is a well characterized tumor suppressor that controls cell proliferation and apoptosis and has also been linked to non-apoptotic, non-canonical cell death mechanisms. p53 impacts these non-canonical forms of cell death through transcriptional regulation of its downstream targets, as well as direct interactions with key players involved in these mechanisms, in a cell type- or tissue context-dependent manner. In this review article, we summarize and discuss the involvement of p53 in several non-canonical modes of cell death, including caspase-independent apoptosis (CIA, ferroptosis, necroptosis, autophagic cell death, mitotic catastrophe, paraptosis, and pyroptosis, as well as its role in efferocytosis which is the process of clearing dead or dying cells.
A canonical theory of dynamic decision-making
Directory of Open Access Journals (Sweden)
John eFox
2013-04-01
Full Text Available Decision-making behaviour is studied in many very different fields, from medicine and economics to psychology and neuroscience, with major contributions from mathematics and statistics, computer science, AI and other technical disciplines. However the conceptualisation of what decision-making is and methods for studying it vary greatly and this has resulted in fragmentation of the field. A theory that can accommodate various perspectives may facilitate interdisciplinary working. We present such a theory in which decision-making is articulated as a set of canonical functions that are sufficiently general to accommodate diverse viewpoints, yet sufficiently precise that they can be instantiated in different ways for specific theoretical or practical purposes. The canons cover the whole decision cycle, from the framing of a decision based on the goals, beliefs, and background knowledge of the decision maker to the formulation of decision options, establishing preferences over them, and making commitments. Commitments can lead to the initiation of new decisions and any step in the cycle can incorporate reasoning about previous decisions and the rationales for them, and lead to revising or abandoning existing commitments. The theory situates decision making with respect to other high-level cognitive capabilities like problem-solving, planning and collaborative decision-making. The canonical approach is assessed in three domains: cognitive and neuro-psychology, artificial intelligence, and decision engineering.
Fast numerical algorithm for the linear canonical transform.
Hennelly, Bryan M; Sheridan, John T
2005-05-01
The linear canonical transform (LCT) describes the effect of any quadratic phase system (QPS) on an input optical wave field. Special cases of the LCT include the fractional Fourier transform (FRT), the Fourier transform (FT), and the Fresnel transform (FST) describing free-space propagation. Currently there are numerous efficient algorithms used (for purposes of numerical simulation in the area of optical signal processing) to calculate the discrete FT, FRT, and FST. All of these algorithms are based on the use of the fast Fourier transform (FFT). In this paper we develop theory for the discrete linear canonical transform (DLCT), which is to the LCT what the discrete Fourier transform (DFT) is to the FT. We then derive the fast linear canonical transform (FLCT), an N log N algorithm for its numerical implementation by an approach similar to that used in deriving the FFT from the DFT. Our algorithm is significantly different from the FFT, is based purely on the properties of the LCT, and can be used for FFT, FRT, and FST calculations and, in the most general case, for the rapid calculation of the effect of any QPS.
On the Theotokia in the Canon for St. Wenceslas
Directory of Open Access Journals (Sweden)
Vittorio Springfield Tomelleri
2016-08-01
Full Text Available The present paper reports on the first results from the investigation of the Church Slavonic canon composed for the Czech saint Wenceslas (Václav, Viacheslav and preserved in East Slavic manuscripts from the end of the 11th century. Particular attention has been given to the analysis of the Marian hymns (theotokia, whose Greek originals could be detected in all cases but one (the first ode. The Slavonic translation has been thoroughly compared with its Greek original and with other versions taken from different canons. Following the critical edition of each single Slavonic text, a synoptic interlinear version is provided, which allows the immediate identification of common readings, errors, and omissions. The theotokia contained in the canon for Wenceslas show interesting similarities with the textual tradition documented in the Oktoechos and the Common of Saints, the latter being usually associated with Clement of Ohrid; a possible explanation of this fact could be that these texts were not newly translated from Greek, but taken from already existing hymnographic sources. Undoubtedly, much deeper analysis is required in order to disentangle the textual history of these texts; the collected material aims to provide a good starting point for further investigations.
Directory of Open Access Journals (Sweden)
Julio Premat
2011-07-01
Full Text Available Este texto, borrador de un trabajo más amplio, pretende despejar algunas pistas de lectura de La grande, en tanto que paradójico final de la producción de Saer. Digo “paradójico” porque puede tomársela como una novela de comienzo o de origen : de un volver a empezar, en todos los sentidos del término. En esa perspectiva podrían estudiarse algunos núcleos temáticos (como el retorno o el recuerdo de cara a la construcción del texto, a la relación planteada con la tradición y a la singular historia de su escritura (y al material genético que rodea y completa esta novela a la vez inacabada y póstuma. En esta intervención, la idea es la de comentar tres textos, escenas o frases del texto, y a partir de allí esbozar pistas para un estudio que está en ciernes.Première ébauche d’un travail de plus d’ampleur, ce texte vise à éclairer quelques pistes de lecture de La grande, en tant que fin paradoxale de la production de Saer. Je dis « paradoxale » parce que l’on peut considérer cette œuvre comme un roman des commencements ou des origines : comme un retour aux débuts, dans tous les sens du terme. Dans cette perspective, plusieurs nœuds thématiques (comme le retour ou le souvenir pourraient être étudiés en relation à la construction du texte, à la relation qui s’établit avec la tradition et à la singulière histoire de son écriture (et au matériau génétique qui entoure et complète ce roman, à la fois inachevé et posthume. Il sera question ici de commenter trois textes, scènes ou phrases du texte, et d’ébaucher à partir de là quelques pistes pour une étude à l’état naissant.The objective of this text, a draft for a broader work, is to outline some reading clues for La grande, inasmuch as it constitutes a paradoxical ending of Saer’s production. I say “paradoxical” because we can consider this work a novel of beginnings or of origins: a return to the beginning, in every meaning of the
International Nuclear Information System (INIS)
Segovia A, M. de N.
1978-01-01
The charged particles produce, in dielectric materials, physical and chemical effects which make evident the damaged zone along the trajectory of the particle. This damaged zone is known as the latent trace. The latent traces can be enlarged by an etching of the detector material. This treatment attacks preferently the zones of the material where the charged particles have penetrated, producing concavities which can be observed through a low magnification optical microscope. These concavities are known as developed traces. In this work we describe the glass characteristics as a detector of the fission fragments traces. In the first chapter we present a summary of the existing basic theories to explain the formation of traces in solids. In the second chapter we describe the etching method used for the traces development. In the following chapters we determine some chatacteristics of the traces formed on the glass, such as: the development optimum time; the diameter variation of the traces and their density according to the temperature variation of the detector; the glass response to a radiation more penetrating than that of the fission fragments; the distribution of the developed traces and the existing relation between this ditribution and the fission fragments of 252 Cf energies. The method which has been used is simple and cheap and can be utilized in laboratories whose resources are limited. The commercial glass which has been employed allows the registration of the fission fragments and subsequently the realization of experiments which involve the counting of the traces as well as the identification of particles. (author)
International Nuclear Information System (INIS)
Perkins, Timothy N.; Dentener, Mieke A.; Stassen, Frank R.; Rohde, Gernot G.; Mossman, Brooke T.; Wouters, Emiel F.M.; Reynaert, Niki L.
2016-01-01
Growth and development of the mature lung is a complex process orchestrated by a number of intricate developmental signaling pathways. Wingless-type MMTV-integration site (WNT) signaling plays critical roles in controlling branching morphogenesis cell differentiation, and formation of the conducting and respiratory airways. In addition, WNT pathways are often re-activated in mature lungs during repair and regeneration. WNT- signaling has been elucidated as a crucial contributor to the development of idiopathic pulmonary fibrosis as well as other hyper-proliferative lung diseases. Silicosis, a detrimental occupational lung disease caused by excessive inhalation of crystalline silica dust, is hallmarked by repeated cycles of damaging inflammation, epithelial hyperplasia, and formation of dense, hyalinized nodules of whorled collagen. However, mechanisms of epithelial cell hyperplasia and matrix deposition are not well understood, as most research efforts have focused on the pronounced inflammatory response. Microarray data from our previous studies has revealed a number of WNT-signaling and WNT-target genes altered by crystalline silica in human lung epithelial cells. In the present study, we utilize pathway analysis to designate connections between genes altered by silica in WNT-signaling networks. Furthermore, we confirm microarray findings by QRT-PCR and demonstrate both activation of canonical (β-catenin) and down-regulation of non-canonical (WNT5A) signaling in immortalized (BEAS-2B) and primary (PBEC) human bronchial epithelial cells. These findings suggest that WNT-signaling and cross-talk with other pathways (e.g. Notch), may contribute to proliferative, fibrogenic and inflammatory responses to silica in lung epithelial cells. - Highlights: • Pathway analysis reveals silica-induced WNT-signaling in lung epithelial cells. • Silica-induced canonical WNT-signaling is mediated by autocrine/paracrine signals. • Crystalline silica decreases non-canonical WNT
Energy Technology Data Exchange (ETDEWEB)
Perkins, Timothy N.; Dentener, Mieke A. [Department of Respiratory Medicine, Maastricht University Medical Centre +, Maastricht University Maastricht (Netherlands); Stassen, Frank R. [Department of Medical Microbiology, Maastricht University Medical Centre +, Maastricht University Maastricht (Netherlands); Rohde, Gernot G. [Department of Respiratory Medicine, Maastricht University Medical Centre +, Maastricht University Maastricht (Netherlands); Mossman, Brooke T. [Department of Pathology, University of Vermont College of Medicine, Burlington, VT (United States); Wouters, Emiel F.M. [Department of Respiratory Medicine, Maastricht University Medical Centre +, Maastricht University Maastricht (Netherlands); Reynaert, Niki L., E-mail: n.reynaert@maastrichtuniversity.nl [Department of Respiratory Medicine, Maastricht University Medical Centre +, Maastricht University Maastricht (Netherlands)
2016-06-15
Growth and development of the mature lung is a complex process orchestrated by a number of intricate developmental signaling pathways. Wingless-type MMTV-integration site (WNT) signaling plays critical roles in controlling branching morphogenesis cell differentiation, and formation of the conducting and respiratory airways. In addition, WNT pathways are often re-activated in mature lungs during repair and regeneration. WNT- signaling has been elucidated as a crucial contributor to the development of idiopathic pulmonary fibrosis as well as other hyper-proliferative lung diseases. Silicosis, a detrimental occupational lung disease caused by excessive inhalation of crystalline silica dust, is hallmarked by repeated cycles of damaging inflammation, epithelial hyperplasia, and formation of dense, hyalinized nodules of whorled collagen. However, mechanisms of epithelial cell hyperplasia and matrix deposition are not well understood, as most research efforts have focused on the pronounced inflammatory response. Microarray data from our previous studies has revealed a number of WNT-signaling and WNT-target genes altered by crystalline silica in human lung epithelial cells. In the present study, we utilize pathway analysis to designate connections between genes altered by silica in WNT-signaling networks. Furthermore, we confirm microarray findings by QRT-PCR and demonstrate both activation of canonical (β-catenin) and down-regulation of non-canonical (WNT5A) signaling in immortalized (BEAS-2B) and primary (PBEC) human bronchial epithelial cells. These findings suggest that WNT-signaling and cross-talk with other pathways (e.g. Notch), may contribute to proliferative, fibrogenic and inflammatory responses to silica in lung epithelial cells. - Highlights: • Pathway analysis reveals silica-induced WNT-signaling in lung epithelial cells. • Silica-induced canonical WNT-signaling is mediated by autocrine/paracrine signals. • Crystalline silica decreases non-canonical WNT
A Grande Reportagem no contexto informativo SIC
Colaço, Vanessa Alexandra Francisco
2014-01-01
Os telespectadores querem ver grandes reportagens? Como evoluíram as audiências da Grande Reportagem SIC? É este o produto premium da estação? Terá este formato um investimento e continuidade garantidas? Estas são algumas das questões formuladas e às quais se procurou dar resposta neste Relatório de Estágio. Neste trabalho traça-se o perfil do programa Grande Reportagem SIC, clarificando a linha editorial que lhe serviu de base, procurando perceber as suas dinâmicas e passando em revista mome...
Supersymmetry and supergravity: Phenomenology and grand unification
International Nuclear Information System (INIS)
Arnowitt, R.; Nath, P.
1993-01-01
A survey is given of supersymmetry and supergravity and their phenomenology. Some of the topics discussed are the basic ideas of global supersymmetry, the minimal supersymmetric Standard Model (MSSM) and its phenomenology, the basic ideas of local supersymmetry (supergravity), grand unification, supersymmetry breaking in supergravity grand unified models, radiative breaking of SU(2) x U(1), proton decay, cosmological constraints, and predictions of supergravity grand unified models. While the number of detailed derivations are necessarily limited, a sufficient number of results are given so that a reader can get a working knowledge of this field
Robb, P; Pawlowski, B
1990-05-01
The results of measuring the ray trace speed and compilation speed of thirty-nine computers in fifty-seven configurations, ranging from personal computers to super computers, are described. A correlation of ray trace speed has been made with the LINPACK benchmark which allows the ray trace speed to be estimated using LINPACK performance data. The results indicate that the latest generation of workstations, using CPUs based on RISC (Reduced Instruction Set Computer) technology, are as fast or faster than mainframe computers in compute-bound situations.
The Resurrection of Jesus: do extra-canonical sources change the landscape?
Directory of Open Access Journals (Sweden)
F P Viljoen
2005-10-01
Full Text Available The resurrection of Jesus is assumed by the New Testament to be a historical event. Some scholars argue, however, that there was no empty tomb, but that the New Testament accounts are midrashic or mythological stories about Jesus.� In this article extra-canonical writings are investigated to find out what light it may throw on intra-canonical tradition. Many extra-canonical texts seemingly have no knowledge of the passion and resurrection, and such traditions may be earlier than the intra-canonical traditions. Was the resurrection a later invention?� Are intra-canonical texts developments of extra-canonical tradition, or vice versa?� This article demonstrates that extra-canonical texts do not materially alter the landscape of enquiry.
Las cinco grandes dimensiones de la personalidad
Directory of Open Access Journals (Sweden)
Jan ter Laak
1996-12-01
Full Text Available Este artículo revisa las distintas posiciones teóricas sobre las cinco grandes dimensiones de la personalidad, mostrando las semejanzas y diferencias entre las posturas teóricas. Esta contribución presenta lo siguiente: (a la génesis del contenido y la estructura de las cinco dimensiones; (b la fortaleza de las cinco dimensiones; (e la relación de las cinco grandes dimensiones con otros constructos de personalidad; (d discute el valor predictivo de las puntuaciones del perfil de las cinco dimensiones para criterios pertinentes; (e analiza el estatus teórico de las cinco dimensiones; (f discute críticas históricas sobre las cinco grandes dimensiones y se formulan respuestas a estas críticas; (g hace conjeturas para el futuro de las cinco grandes dimensiones; y (h concluye con algunas conclusiones y comentarios.
Directory of Open Access Journals (Sweden)
Diana T. Kudaibergenova
2018-01-01
Full Text Available The Soviet canonisation of Abai, the nineteenth-century Kazakh poet and enlightener became a problematic theme for local intellectuals in the 2010s after the Occupy Abai movement in Moscow raised concerns over the heritage of Abai as a Sovietised canon and as an independent non-Soviet thinker. In 2012 oppositional leaders in Russia occupied Abai monument in Moscow and the leader of the opposition Alexey Navalny, called for his supporters to gather around the monument to unknown strange Kazakh guy using the Russian slang word – neponyatnii Kazakh. Local audience in Kazakhstan at first responded with offensive comments and questions to the Russian opposition movement – how come Abai, the Kazakh version of Russian poet and a visionary Alexander Pushkin, the symbol and canon of Soviet Kazakh literature and the symbol of post-Soviet Kazakhness and its culture could be unknown and strange? From the celebrated writer of the Soviet dekadas and Leninist prizes for Mukhtar Auezov's novel The Path of Abai (Abai Zholy Abai turned into neponyatnii – incomprehensible, strange (in words of Russian Alexey Navalny and neponyatii – misunderstood poet. These discussions on popular online Russophone as well as Kazakhophone platforms and blogs opened up a debate on the legacy and problematic canonisation of Abai. Is Abai misunderstood in contemporary Kazakhstani society? From short essays when famous writer Gerold Belger speaks to Abai's monument in central Almaty to mobile phone applications featuring Abai's Qara Sozder, to the famous anonymous Abai graffiti in central Almaty and Occupy Abai movement responses in Kazakh internet sphere, I trace the mutations of Abai's canon. These discussions reveal the conflicting trends of young Kazakhs and Kazakhstanis who take their cultural criticisms online but continue using the “national” frameworks in their globalized discussions.
Grand unification and gravity - selected topics
International Nuclear Information System (INIS)
Zee, A.
1981-09-01
The material given here was presented in lectures delivered at the 4th Kyoto Summer Institute on Grand Unification and Related Topics. It consists of six sections. The sections are: the family problem, fermion mass hierarchy, maximal local symmetry, operator analysis of new physics, dynamically generated gravity, and Kaluza theory and grand unification. The last section contains a (hopefully) pedagogical introduction to Kaluza theory. For pedagogical completeness, several appendices reviewing some elementary notions of differential geometry have been added
Davis, Ronald L.
2012-01-01
Summary Studies using functional cellullar imaging of living flies have identified six memory traces that form in the olfactory nervous system after conditioning with odors. These traces occur in distinct nodes of the olfactory nervous system, form and disappear across different windows of time, and are detected in the imaged neurons as increased calcium influx or synaptic release in response to the conditioned odor. Three traces form at, or near acquisition and co-exist with short-term behavioral memory. One trace forms with a delay after learning and co-exists with intermediate-term behavioral memory. Two traces form many hours after acquisition and co-exist with long-term behavioral memory. The transient memory traces may support behavior across the time-windows of their existence. The experimental approaches for dissecting memory formation in the fly, ranging from the molecular to the systems, make it an ideal system for dissecting the logic by which the nervous system organizes and stores different temporal forms of memory. PMID:21482352
Kavelund, Klaus; Barringer, Howard
2012-01-01
TraceContract is an API (Application Programming Interface) for trace analysis. A trace is a sequence of events, and can, for example, be generated by a running program, instrumented appropriately to generate events. An event can be any data object. An example of a trace is a log file containing events that a programmer has found important to record during a program execution. Trace - Contract takes as input such a trace together with a specification formulated using the API and reports on any violations of the specification, potentially calling code (reactions) to be executed when violations are detected. The software is developed as an internal DSL (Domain Specific Language) in the Scala programming language. Scala is a relatively new programming language that is specifically convenient for defining such internal DSLs due to a number of language characteristics. This includes Scala s elegant combination of object-oriented and functional programming, a succinct notation, and an advanced type system. The DSL offers a combination of data-parameterized state machines and temporal logic, which is novel. As an extension of Scala, it is a very expressive and convenient log file analysis framework.
Canonical transformation path to gauge theories of gravity
Struckmeier, J.; Muench, J.; Vasak, D.; Kirsch, J.; Hanauske, M.; Stoecker, H.
2017-06-01
In this paper, the generic part of the gauge theory of gravity is derived, based merely on the action principle and on the general principle of relativity. We apply the canonical transformation framework to formulate geometrodynamics as a gauge theory. The starting point of our paper is constituted by the general De Donder-Weyl Hamiltonian of a system of scalar and vector fields, which is supposed to be form-invariant under (global) Lorentz transformations. Following the reasoning of gauge theories, the corresponding locally form-invariant system is worked out by means of canonical transformations. The canonical transformation approach ensures by construction that the form of the action functional is maintained. We thus encounter amended Hamiltonian systems which are form-invariant under arbitrary spacetime transformations. This amended system complies with the general principle of relativity and describes both, the dynamics of the given physical system's fields and their coupling to those quantities which describe the dynamics of the spacetime geometry. In this way, it is unambiguously determined how spin-0 and spin-1 fields couple to the dynamics of spacetime. A term that describes the dynamics of the "free" gauge fields must finally be added to the amended Hamiltonian, as common to all gauge theories, to allow for a dynamic spacetime geometry. The choice of this "dynamics" Hamiltonian is outside of the scope of gauge theory as presented in this paper. It accounts for the remaining indefiniteness of any gauge theory of gravity and must be chosen "by hand" on the basis of physical reasoning. The final Hamiltonian of the gauge theory of gravity is shown to be at least quadratic in the conjugate momenta of the gauge fields—this is beyond the Einstein-Hilbert theory of general relativity.
Denominator function for canonical SU(3) tensor operators
International Nuclear Information System (INIS)
Biedenharn, L.C.; Lohe, M.A.; Louck, J.D.
1985-01-01
The definition of a canonical unit SU(3) tensor operator is given in terms of its characteristic null space as determined by group-theoretic properties of the intertwining number. This definition is shown to imply the canonical splitting conditions used in earlier work for the explicit and unique (up to +- phases) construction of all SU(3) WCG coefficients (Wigner--Clebsch--Gordan). Using this construction, an explicit SU(3)-invariant denominator function characterizing completely the canonically defined WCG coefficients is obtained. It is shown that this denominator function (squared) is a product of linear factors which may be obtained explicitly from the characteristic null space times a ratio of polynomials. These polynomials, denoted G/sup t//sub q/, are defined over three (shift) parameters and three barycentric coordinates. The properties of these polynomials (hence, of the corresponding invariant denominator function) are developed in detail: These include a derivation of their degree, symmetries, and zeros. The symmetries are those induced on the shift parameters and barycentric coordinates by the transformations of a 3 x 3 array under row interchange, column interchange, and transposition (the group of 72 operations leaving a 3 x 3 determinant invariant). Remarkably, the zeros of the general G/sup t//sub q/ polynomial are in position and multiplicity exactly those of the SU(3) weight space associated with irreducible representation [q-1,t-1,0]. The results obtained are an essential step in the derivation of a fully explicit and comprehensible algebraic expression for all SU(3) WCG coefficients
Directory of Open Access Journals (Sweden)
Po-Han eLin
2012-02-01
Full Text Available The change detection task has become a standard method for estimating the storage capacity of visual working memory. Most researchers assume that this task isolates the properties of an active short-term storage system that can be dissociated from long-term memory systems. However, long-term memory storage may influence performance on this task. In particular, memory traces from previous trials may create proactive interference that sometimes leads to errors, thereby reducing estimated capacity. Consequently, the capacity of visual working memory may be higher than is usually thought, and correlations between capacity and other measures of cognition may reflect individual differences in proactive interference rather than individual differences in the capacity of the short-term storage system. Indeed, previous research has shown that change detection performance can be influenced by proactive interference under some conditions. The purpose of the present study was to determine whether the canonical version of the change detection task—in which the to-be-remembered information consists of simple, briefly presented features—is influenced by proactive interference. Two experiments were conducted using methods that ordinarily produce substantial evidence of proactive interference, but no proactive interference was observed. Thus, the canonical version of the change detection task can be used to assess visual working memory capacity with no meaningful influence of proactive interference.
Lin, Po-Han; Luck, Steven J
2012-01-01
The change detection task has become a standard method for estimating the storage capacity of visual working memory. Most researchers assume that this task isolates the properties of an active short-term storage system that can be dissociated from long-term memory systems. However, long-term memory storage may influence performance on this task. In particular, memory traces from previous trials may create proactive interference that sometimes leads to errors, thereby reducing estimated capacity. Consequently, the capacity of visual working memory may be higher than is usually thought, and correlations between capacity and other measures of cognition may reflect individual differences in proactive interference rather than individual differences in the capacity of the short-term storage system. Indeed, previous research has shown that change detection performance can be influenced by proactive interference under some conditions. The purpose of the present study was to determine whether the canonical version of the change detection task - in which the to-be-remembered information consists of simple, briefly presented features - is influenced by proactive interference. Two experiments were conducted using methods that ordinarily produce substantial evidence of proactive interference, but no proactive interference was observed. Thus, the canonical version of the change detection task can be used to assess visual working memory capacity with no meaningful influence of proactive interference.
A second-order unconstrained optimization method for canonical-ensemble density-functional methods
Nygaard, Cecilie R.; Olsen, Jeppe
2013-03-01
A second order converging method of ensemble optimization (SOEO) in the framework of Kohn-Sham Density-Functional Theory is presented, where the energy is minimized with respect to an ensemble density matrix. It is general in the sense that the number of fractionally occupied orbitals is not predefined, but rather it is optimized by the algorithm. SOEO is a second order Newton-Raphson method of optimization, where both the form of the orbitals and the occupation numbers are optimized simultaneously. To keep the occupation numbers between zero and two, a set of occupation angles is defined, from which the occupation numbers are expressed as trigonometric functions. The total number of electrons is controlled by a built-in second order restriction of the Newton-Raphson equations, which can be deactivated in the case of a grand-canonical ensemble (where the total number of electrons is allowed to change). To test the optimization method, dissociation curves for diatomic carbon are produced using different functionals for the exchange-correlation energy. These curves show that SOEO favors symmetry broken pure-state solutions when using functionals with exact exchange such as Hartree-Fock and Becke three-parameter Lee-Yang-Parr. This is explained by an unphysical contribution to the exact exchange energy from interactions between fractional occupations. For functionals without exact exchange, such as local density approximation or Becke Lee-Yang-Parr, ensemble solutions are favored at interatomic distances larger than the equilibrium distance. Calculations on the chromium dimer are also discussed. They show that SOEO is able to converge to ensemble solutions for systems that are more complicated than diatomic carbon.
Canonical quantization of spinning relativistic particle in external backgrounds
Energy Technology Data Exchange (ETDEWEB)
Gavrilov, S.P. [Universidade Federal de Sergipe (UFS), Aracaju, SE (Brazil); Gitman, D.M. [Sao Paulo Univ. (USP), SP (Brazil). Inst. de Fisica
2000-07-01
Full text follows: We revise the problem of the quantization of spinning relativistic particle pseudoclassical model, using a modified consistent canonical scheme. It allows one not only to include arbitrary electromagnetic and gravitational backgrounds in the consideration but to get in course of the quantization a consistent relativistic quantum mechanics, which reproduces literally the behavior of the one-particle sector of quantized spinor field. In particular, in a physical sector of the Hilbert space a complete positive spectrum of energies of relativistic particles and antiparticles is reproduced. Requirement to maintain all classical symmetries under the coordinate transformations and under U(1) transformations allows one to realize operator algebra without any ambiguities. (author)
El canon literario mexicano en Los detectives salvajes
Directory of Open Access Journals (Sweden)
Carmen de Mora
2015-02-01
Full Text Available En el presente artículo se examina el canon personal de Bolaño en Los detectives salvajes acerca de la literatura mexicana, a partir de la intertextualidad entendida como un rasgo característico de la narrativa postmoderna del autor. Para ello se han tenido en cuenta tanto las citas explícitas que aparecen en la novela como algunas citas implícitas fundamentales. A través del análisis de las mismas se pretende demostrar que para entender el alcance de esta obra es preciso enfrentarse a su escritura en palimpsesto.
El canon literario mexicano en "Los detectives salvajes"
Mora Valcárcel, Carmen de
2015-01-01
En el presente artículo se examina el canon personal de Bolaño en Los detectives salvajes acerca de la literatura mexicana, a partir de la intertextualidad entendida como un rasgo característico de la narrativa postmoderna del autor. Para ello se han tenido en cuenta tanto las citas explícitas que aparecen en la novela como algunas citas implícitas fundamentales. A través del análisis de las mismas se pretende demostrar que para entender el alcance de esta obra es preciso enfrentarse a su esc...
Discrete linear canonical transforms based on dilated Hermite functions.
Pei, Soo-Chang; Lai, Yun-Chiu
2011-08-01
Linear canonical transform (LCT) is very useful and powerful in signal processing and optics. In this paper, discrete LCT (DLCT) is proposed to approximate LCT by utilizing the discrete dilated Hermite functions. The Wigner distribution function is also used to investigate DLCT performances in the time-frequency domain. Compared with the existing digital computation of LCT, our proposed DLCT possess additivity and reversibility properties with no oversampling involved. In addition, the length of input/output signals will not be changed before and after the DLCT transformations, which is consistent with the time-frequency area-preserving nature of LCT; meanwhile, the proposed DLCT has very good approximation of continuous LCT.
On two mathematical problems of canonical quantization. 1
International Nuclear Information System (INIS)
Kirillov, A.I.
1991-01-01
Problems of choice a representation of the canonical commutation relations (CCR) and determining of Hamiltonian are investigated. It is shown that the Hamiltonians studied by H. Araki are the Dirichlet operators. The almost inverse theorem is also proved. Dirichlet operators are completely determined by measures. The same measures specify also representations of CCR and ground states. A notion of generalized density of these measures is introduced. Calculation methods of the densities and its corresponding measures, i.e. in the end, of representations of CCR and Hamiltonians interrelated in the meaning of L.Van Hove, are suggested
Canonical commutation relations - historical aspect and new results
International Nuclear Information System (INIS)
Mnatsakanova, M.N.; Vernov, Yu.S.
1997-01-01
The aim of the paper is to describe the historical aspects of the canonical commutation relations (CCR) and to analyse the new results. The CCR are the algebraic structure (Heisenberg algebra) on the basis of quantum mechanics and quantum field theory. The following results are discussed: the Weyl form of CCR, Von Neumann's uniqueness theorem, regularity conditions, CCR representation in standard and Weyl forms, CCR in an indefinite metric space, class of CCR regular representations and CCR in the case of infinite number of degrees of freedom [ru
Distribution for fermionic discrete lattice gas within the canonical ensemble
International Nuclear Information System (INIS)
Kutner, R.; Barszczak, T.
1991-01-01
The distinct deviations from the Fermi-Dirac statistics ascertained recently at low temperatures for a one-dimensional, spinless fermionic discrete lattice gas with conserved number of noninteracting particles hopping on the nondegenerated, well-separated single-particle energy levels are studied in numerical and theoretical terms. The generalized distribution is derived in the form n(h) = {Y h exp[(var-epsilon h -μ)β]+1} -1 valid even in the thermodynamic limit, when the discreteness of the energy levels is kept. This distribution demonstrates good agreement with the data obtained numerically both by the canonical partition-function technique and by Monte Carlo simulation
Canonical quantization of general relativity in discrete space-times.
Gambini, Rodolfo; Pullin, Jorge
2003-01-17
It has long been recognized that lattice gauge theory formulations, when applied to general relativity, conflict with the invariance of the theory under diffeomorphisms. We analyze discrete lattice general relativity and develop a canonical formalism that allows one to treat constrained theories in Lorentzian signature space-times. The presence of the lattice introduces a "dynamical gauge" fixing that makes the quantization of the theories conceptually clear, albeit computationally involved. The problem of a consistent algebra of constraints is automatically solved in our approach. The approach works successfully in other field theories as well, including topological theories. A simple cosmological application exhibits quantum elimination of the singularity at the big bang.
A multimodal stress monitoring system with canonical correlation analysis.
Unsoo Ha; Changhyeon Kim; Yongsu Lee; Hyunki Kim; Taehwan Roh; Hoi-Jun Yoo
2015-08-01
The multimodal stress monitoring headband is proposed for mobile stress management system. It is composed of headband and earplugs. Electroencephalography (EEG), hemoencephalography (HEG) and heart-rate variability (HRV) can be achieved simultaneously in the proposed system for user status estimation. With canonical correlation analysis (CCA) and temporal-kernel CCA (tkCCA) algorithm, those different signals can be combined for maximum correlation. Thanks to the proposed combination algorithm, the accuracy of the proposed system increased up to 19 percentage points than unimodal monitoring system in n-back task.
Discrete linear canonical transform computation by adaptive method.
Zhang, Feng; Tao, Ran; Wang, Yue
2013-07-29
The linear canonical transform (LCT) describes the effect of quadratic phase systems on a wavefield and generalizes many optical transforms. In this paper, the computation method for the discrete LCT using the adaptive least-mean-square (LMS) algorithm is presented. The computation approaches of the block-based discrete LCT and the stream-based discrete LCT using the LMS algorithm are derived, and the implementation structures of these approaches by the adaptive filter system are considered. The proposed computation approaches have the inherent parallel structures which make them suitable for efficient VLSI implementations, and are robust to the propagation of possible errors in the computation process.
Canonical harmonic tracking of charged particles in circular accelerators
International Nuclear Information System (INIS)
Kvardakov, V.; Levichev, E.
2006-01-01
Harmonic tracking is a method used to study non-linear particle dynamics in a circular accelerator. The tracking algorithm is based on numerical solution of the Hamilton equations of motion. An essential feature of the method is the approximation of Hamiltonian perturbation terms by a finite number of azimuthal harmonics, which provides an effective tool for optimization of non-linear particle motion. The equations of motion are solved canonically, with the first-order prediction made using the explicit Lie transformation. The major features of harmonic tracking are presented and examples of its application are discussed
Canonical harmonic tracking of charged particles in circular accelerators
Kvardakov, V.; Levichev, E.
2006-03-01
Harmonic tracking is a method used to study non-linear particle dynamics in a circular accelerator. The tracking algorithm is based on numerical solution of the Hamilton equations of motion. An essential feature of the method is the approximation of Hamiltonian perturbation terms by a finite number of azimuthal harmonics, which provides an effective tool for optimization of non-linear particle motion. The equations of motion are solved canonically, with the first-order prediction made using the explicit Lie transformation. The major features of harmonic tracking are presented and examples of its application are discussed.
Optimization algorithm based on densification and dynamic canonical descent
Bousson, K.; Correia, S. D.
2006-07-01
Stochastic methods have gained some popularity in global optimization in that most of them do not assume the cost functions to be differentiable. They have capabilities to avoid being trapped by local optima, and may converge even faster than gradient-based optimization methods on some problems. The present paper proposes an optimization method, which reduces the search space by means of densification curves, coupled with the dynamic canonical descent algorithm. The performances of the new method are shown on several known problems classically used for testing optimization algorithms, and proved to outperform competitive algorithms such as simulated annealing and genetic algorithms.
Currents, charges, and canonical structure of pseudodual chiral models
International Nuclear Information System (INIS)
Curtright, T.; Zachos, C.
1994-01-01
We discuss the pseudodual chiral model to illustrate a class of two-dimensional theories which have an infinite number of conservation laws but allow particle production, at variance with naive expectations. We describe the symmetries of the pseudodual model, both local and nonlocal, as transmutations of the symmetries of the usual chiral model. We refine the conventional algorithm to more efficiently produce the nonlocal symmetries of the model, and we discuss the complete local current algebra for the pseudodual theory. We also exhibit the canonical transformation which connects the usual chiral model to its fully equivalent dual, further distinguishing the pseudodual theory
Canonical Transform Method for Treating Strongly Anisotropy Magnets
DEFF Research Database (Denmark)
Cooke, J. F.; Lindgård, Per-Anker
1977-01-01
An infinite-order perturbation approach to the theory of magnetism in magnets with strong single-ion anisotropy is given. This approach is based on a canonical transformation of the system into one with a diagonal crystal field, an effective two-ion anisotropy, and reduced ground-state corrections....... A matrix-element matching procedure is used to obtain an explicit expression for the spin-wave energy to second order. The consequences of this theory are illustrated by an application to a simple example with planar anisotropy and an external magnetic field. A detailed comparison between the results...
Parametric potential determination by the canonical function method
International Nuclear Information System (INIS)
Tannous, C.; Fakhreddine, K.; Langlois, J.
1999-01-01
The canonical function method (CFM) is a powerful means for solving the radial Schroedinger equation (RSE). The mathematical difficulty of the RSE lies in the fact it is a singular boundary value problem. The CFM turns it into a regular initial value problem and allows the full determination of the spectrum of the Schroedinger operator without calculating the eigenfunctions. Following the parametrisation suggested by Klapisch and Green-Sellin-Zachor we develop a CFM to optimise the potential parameters in order to reproduce the experimental quantum defect results for various Rydberg series of He, Ne and Ar as evaluated from Moore's data. (orig.)
Origins and canons: medicine and the history of sociology.
Collyer, Fran
2010-01-01
Differing accounts are conventionally given of the origins of medical sociology and its parent discipline sociology. These distinct "histories" are justified on the basis that the sociological founders were uninterested in medicine, mortality and disease. This article challenges these "constructions" of the past, proposing the theorization of health not as a "late development of sociology" but an integral part of its formation. Drawing on a selection of key sociological texts, it is argued that evidence of the founders' sustained interest in the infirmities of the individual, of mortality, and in medicine, have been expunged from the historical record through processes of "canonization" and "medicalization."
Chemical stratigraphy of Grande Ronde Basalt, Pasco Basin, south-central Washington
International Nuclear Information System (INIS)
Long, P.E.; Ledgerwood, R.K.; Myers, C.W.; Reidel, S.P.; Landon, R.D.; Hooper, P.R.
1980-02-01
Grande Ronde Basalt in the Pasco Basin, south-central Washington, can be subdivided into three chemical types and two chemical subtypes based on x-ray fluorescence major element analysis of samples from seven deep core holes and three surface sections. These chemical types are: (1) high-Mg Grande Ronde chemical type; (2) low-Mg Grande Ronde chemical type; (3) low-K (very high-Mg.) Grande Ronde chemical type; and (4) Umtanum Grande Ronde chemical subtype. A possible fifth subdivision is the McCoy Canyon Grande Ronde chemical subtype. The Umtanum and the McCoy Canyon subtypes are both single flows which belong to the low Mg and high-Mg chemical types, respectively. These subdivisions are all distinguished on a plot of MgO versus TiO 2 and/or MgO versus P 2 O 5 , but other major and minor elements, as well as trace elements, also reflect consistent chemical differences between the chemical types. Identification of these chemical types in the Pasco Basin subsurface shows that the high-Mg and low-Mg chemical types are ubiquitous, but the low-K chemical type is limited to the central, southern, and eastern parts of the basin. The Umtanum chemical subtype is present throughout the Pasco Basin subsurface, although it thins in the northeastern part of the basin and is apparently absent from surface exposures 40 kilometers (25 miles) north of the basin. The McCoy Canyon chemical subtype is also present throughout the basin
CANONICAL CORRELATION OF MORPHOLOGIC CHARACTERISTIC AND MOTORIC ABILITIES OF YOUNG JUDO ATHLETES
Directory of Open Access Journals (Sweden)
Lulzim Ibri
2013-07-01
Full Text Available In sample from 80 young judo athletes aged from 16-17 year, was applied the system a total of 18 variables, of which 10 are morphologic characteristic and 8 motoric abilities variables, with a purpose to determinate mutual report between each other, while the information were analyzed by using canonical correlation analysis. With case of authentication statistically important relation was achieve one pair of canonical correlations statistically important. In morphologic variables field the canonical factor is interpreted in first canonical structure is the consists of variables: adipose tissue under skin of stomach (ATST, adipose tissue under skin of triceps (ATTR, adipose tissue under skin of biceps (ATBI, adipose tissue under skin of sub scapulars (ATSS, adipose tissue under skin of sub iliac a (ATSI and adipose tissue under skin of list (ATSL, so that is interpreted as a canonical factor of adipose tissue: And second structure of canonical factors of anthropometric characteristics is the consists of variables: body length: body length (LEBO, length of the leg (LELE and length of the arm (LEAR, so that is interpreted as a canonical factor of longitudinal dimensionality. The first structure of canonical factors in motoric variables is can not be interpreted because of low values of motor variables, while second structure of canonical factors of motoric abilities is the consists of variables: squeeze palm (SQPA, so that is interpreted as a canonical factor of strong factor in palm. Based on structure analysis of matrix results of canonical factors results were shown that to young judo athletes of this age exist statistically valid correlations between canonical factor of anthropometric variables and canonical factor of variables to motoric abilities which is (Rc=77 that is statistically valid in level (P=00.
Geometric integrator for simulations in the canonical ensemble
Energy Technology Data Exchange (ETDEWEB)
Tapias, Diego, E-mail: diego.tapias@nucleares.unam.mx [Departamento de Física, Facultad de Ciencias, Universidad Nacional Autónoma de México, Ciudad Universitaria, Ciudad de México 04510 (Mexico); Sanders, David P., E-mail: dpsanders@ciencias.unam.mx [Departamento de Física, Facultad de Ciencias, Universidad Nacional Autónoma de México, Ciudad Universitaria, Ciudad de México 04510 (Mexico); Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139 (United States); Bravetti, Alessandro, E-mail: alessandro.bravetti@iimas.unam.mx [Instituto de Investigaciones en Matemáticas Aplicadas y en Sistemas, Universidad Nacional Autónoma de México, Ciudad Universitaria, Ciudad de México 04510 (Mexico)
2016-08-28
We introduce a geometric integrator for molecular dynamics simulations of physical systems in the canonical ensemble that preserves the invariant distribution in equations arising from the density dynamics algorithm, with any possible type of thermostat. Our integrator thus constitutes a unified framework that allows the study and comparison of different thermostats and of their influence on the equilibrium and non-equilibrium (thermo-)dynamic properties of a system. To show the validity and the generality of the integrator, we implement it with a second-order, time-reversible method and apply it to the simulation of a Lennard-Jones system with three different thermostats, obtaining good conservation of the geometrical properties and recovering the expected thermodynamic results. Moreover, to show the advantage of our geometric integrator over a non-geometric one, we compare the results with those obtained by using the non-geometric Gear integrator, which is frequently used to perform simulations in the canonical ensemble. The non-geometric integrator induces a drift in the invariant quantity, while our integrator has no such drift, thus ensuring that the system is effectively sampling the correct ensemble.
Lie algebras under constraints and nonbijective canonical transformations
International Nuclear Information System (INIS)
Kibler, M.; Winternitz, P.
1987-10-01
The concept of a Lie algebra under constraints is developed in connection with the theory of nonbijective canonical transformations. A finite dimensional vector space M, carrying a faithful linear representation of a Lie algebra L, is mapped into a lower dimensional space antiM in such a maner that a subalgebra L 0 of L is mapped into D(L 0 ) = 0. The Lie algebra L under the constraint D(L 0 ) = 0 is the largest subalgebra L 1 of L that can be represented faithfully on antiM. If L 0 is semi-simple, then L 1 is shown to be the centraliser cent L L 0 . If L is semi-simple and L 0 is an one-dimensional diagonal subalgebra of a Cartan subalgebra of L, then L 1 is shown to be the factor algebra cent L L 0 /L 0 . The latter two results are applied to nonbijective canonical transformations generalizing the Kustaanheimo-Stiefel transformation
Data analytics using canonical correlation analysis and Monte Carlo simulation
Rickman, Jeffrey M.; Wang, Yan; Rollett, Anthony D.; Harmer, Martin P.; Compson, Charles
2017-07-01
A canonical correlation analysis is a generic parametric model used in the statistical analysis of data involving interrelated or interdependent input and output variables. It is especially useful in data analytics as a dimensional reduction strategy that simplifies a complex, multidimensional parameter space by identifying a relatively few combinations of variables that are maximally correlated. One shortcoming of the canonical correlation analysis, however, is that it provides only a linear combination of variables that maximizes these correlations. With this in mind, we describe here a versatile, Monte-Carlo based methodology that is useful in identifying non-linear functions of the variables that lead to strong input/output correlations. We demonstrate that our approach leads to a substantial enhancement of correlations, as illustrated by two experimental applications of substantial interest to the materials science community, namely: (1) determining the interdependence of processing and microstructural variables associated with doped polycrystalline aluminas, and (2) relating microstructural decriptors to the electrical and optoelectronic properties of thin-film solar cells based on CuInSe2 absorbers. Finally, we describe how this approach facilitates experimental planning and process control.
Geometric integrator for simulations in the canonical ensemble
International Nuclear Information System (INIS)
Tapias, Diego; Sanders, David P.; Bravetti, Alessandro
2016-01-01
We introduce a geometric integrator for molecular dynamics simulations of physical systems in the canonical ensemble that preserves the invariant distribution in equations arising from the density dynamics algorithm, with any possible type of thermostat. Our integrator thus constitutes a unified framework that allows the study and comparison of different thermostats and of their influence on the equilibrium and non-equilibrium (thermo-)dynamic properties of a system. To show the validity and the generality of the integrator, we implement it with a second-order, time-reversible method and apply it to the simulation of a Lennard-Jones system with three different thermostats, obtaining good conservation of the geometrical properties and recovering the expected thermodynamic results. Moreover, to show the advantage of our geometric integrator over a non-geometric one, we compare the results with those obtained by using the non-geometric Gear integrator, which is frequently used to perform simulations in the canonical ensemble. The non-geometric integrator induces a drift in the invariant quantity, while our integrator has no such drift, thus ensuring that the system is effectively sampling the correct ensemble.
Nonbijective canonical transformations and applications to some dynamical systems
International Nuclear Information System (INIS)
Negadi, T.
1988-01-01
A first part is devoted to a presentation of a simplified formalism concerning non-bijective canonical transformations and to an interpretation of some of them in the framework on the theory of Lie algebras. In particular, the well-known Levi-Civita and Kustaanheimo-Stiefel transformations are generalized to the non-compact case and to the dimensions 2, 4 and 8. The differential and geometrical properties of the so-called Hurwitz transformations as well as their interpretation in terms of Lie algebras under constraints are given. A second part is concerned with the application of certain non-bijective canonical transformations (and in particular the Kustaanheimo-Stiefel transformation) to some dynamical systems of interest in theoretical and in chemical physics. The applications concern especially hydrogenoid systems, free or embedded in static and uniform electromagnetic fields, and systems presenting a line of singularity (as the Hartmann system, the Aharonov-Bohm system, and the dyonium system). The Kustaanheimo-Stiefel transformation allows to convert the Schroedinger equations for the later systems into Schroedinger equations for oscillators (harmonic, anharmonic, non-harmonic) in 2 or 4 dimensions [fr
The gauge-invariant canonical energy-momentum tensor
Lorcé, Cédric
2016-03-01
The canonical energy-momentum tensor is often considered as a purely academic object because of its gauge dependence. However, it has recently been realized that canonical quantities can in fact be defined in a gauge-invariant way provided that strict locality is abandoned, the non-local aspect being dictacted in high-energy physics by the factorization theorems. Using the general techniques for the parametrization of non-local parton correlators, we provide for the first time a complete parametrization of the energy-momentum tensor (generalizing the purely local parametrizations of Ji and Bakker-Leader-Trueman used for the kinetic energy-momentum tensor) and identify explicitly the parts accessible from measurable two-parton distribution functions (TMDs and GPDs). As by-products, we confirm the absence of model-independent relations between TMDs and parton orbital angular momentum, recover in a much simpler way the Burkardt sum rule and derive three similar new sum rules expressing the conservation of transverse momentum.
The gauge-invariant canonical energy-momentum tensor
International Nuclear Information System (INIS)
Lorce, C.
2016-01-01
The canonical energy-momentum tensor is often considered as a purely academic object because of its gauge dependence. However, it has recently been realized that canonical quantities can in fact be defined in a gauge-invariant way provided that strict locality is abandoned, the non-local aspect being dictated in high-energy physics by the factorization theorems. Using the general techniques for the parametrization of non-local parton correlators, we provide for the first time a complete parametrization of the energy-momentum tensor (generalizing the purely local parametrizations of Ji and Bakker-Leader-Trueman used for the kinetic energy-momentum tensor) and identify explicitly the parts accessible from measurable two-parton distribution functions (TMD and GPD). As by-products, we confirm the absence of model-independent relations between TMDs and parton orbital angular momentum, recover in a much simpler way the Burkardt sum rule and derive 3 similar new sum rules expressing the conservation of transverse momentum. (author)
Scalable and Flexible Multiview MAX-VAR Canonical Correlation Analysis
Fu, Xiao; Huang, Kejun; Hong, Mingyi; Sidiropoulos, Nicholas D.; So, Anthony Man-Cho
2017-08-01
Generalized canonical correlation analysis (GCCA) aims at finding latent low-dimensional common structure from multiple views (feature vectors in different domains) of the same entities. Unlike principal component analysis (PCA) that handles a single view, (G)CCA is able to integrate information from different feature spaces. Here we focus on MAX-VAR GCCA, a popular formulation which has recently gained renewed interest in multilingual processing and speech modeling. The classic MAX-VAR GCCA problem can be solved optimally via eigen-decomposition of a matrix that compounds the (whitened) correlation matrices of the views; but this solution has serious scalability issues, and is not directly amenable to incorporating pertinent structural constraints such as non-negativity and sparsity on the canonical components. We posit regularized MAX-VAR GCCA as a non-convex optimization problem and propose an alternating optimization (AO)-based algorithm to handle it. Our algorithm alternates between {\\em inexact} solutions of a regularized least squares subproblem and a manifold-constrained non-convex subproblem, thereby achieving substantial memory and computational savings. An important benefit of our design is that it can easily handle structure-promoting regularization. We show that the algorithm globally converges to a critical point at a sublinear rate, and approaches a global optimal solution at a linear rate when no regularization is considered. Judiciously designed simulations and large-scale word embedding tasks are employed to showcase the effectiveness of the proposed algorithm.
A Synthetic Alternative to Canonical One-Carbon Metabolism.
Bouzon, Madeleine; Perret, Alain; Loreau, Olivier; Delmas, Valérie; Perchat, Nadia; Weissenbach, Jean; Taran, Frédéric; Marlière, Philippe
2017-08-18
One-carbon metabolism is an ubiquitous metabolic pathway that encompasses the reactions transferring formyl-, hydroxymethyl- and methyl-groups bound to tetrahydrofolate for the synthesis of purine nucleotides, thymidylate, methionine and dehydropantoate, the precursor of coenzyme A. An alternative cyclic pathway was designed that substitutes 4-hydroxy-2-oxobutanoic acid (HOB), a compound absent from known metabolism, for the amino acids serine and glycine as one-carbon donors. It involves two novel reactions, the transamination of l-homoserine and the transfer of a one-carbon unit from HOB to tetrahydrofolate releasing pyruvate as coproduct. Since canonical reactions regenerate l-homoserine from pyruvate by carboxylation and subsequent reduction, every one-carbon moiety made available for anabolic reactions originates from CO 2 . The HOB-dependent pathway was established in an Escherichia coli auxotroph selected for prototrophy using long-term cultivation protocols. Genetic, metabolic and biochemical evidence support the emergence of a functional HOB-dependent one-carbon pathway achieved with the recruitment of the two enzymes l-homoserine transaminase and HOB-hydroxymethyltransferase and of HOB as an essential metabolic intermediate. Escherichia coli biochemical reprogramming was achieved by minimally altering canonical metabolism and leveraging on natural selection mechanisms, thereby launching the resulting strain on an evolutionary trajectory diverging from all known extant species.
The energy–momentum tensor, the trace identity and the Casimir effect
Indian Academy of Sciences (India)
ˆΘµν is defined [1] in terms of the canonical energy-momentum tensor. ˆΘµν ... we shall first use standard methods in the sequel to check that the trace identity ... with a short Appendix that includes a derivation of some of the relevant equations ..... in (19), but after contraction with gαβ, remembering that the partial derivative.
2010 Panel on the Biomaterials Grand Challenges
Reichert, William “Monty”; Ratner, Buddy D.; Anderson, James; Coury, Art; Hoffman, Allan S.; Laurencin, Cato T.; Tirrell, David
2014-01-01
In 2009, the National Academy for Engineering issued the Grand Challenges for Engineering in the 21st Century comprised of 14 technical challenges that must be addressed to build a healthy, profitable, sustainable, and secure global community (http://www.engineeringchallenges.org). Although crucial, none of the NEA Grand Challenges adequately addressed the challenges that face the biomaterials community. In response to the NAE Grand Challenges, Monty Reichert of Duke University organized a panel entitled Grand Challenges in Biomaterials at the at the 2010 Society for Biomaterials Annual Meeting in Seattle. Six members of the National Academies—Buddy Ratner, James Anderson, Allan Hoffman, Art Coury, Cato Laurencin, and David Tirrell—were asked to propose a grand challenge to the audience that, if met, would significantly impact the future of biomaterials and medical devices. Successfully meeting these challenges will speed the 60-plus year transition from commodity, off-the-shelf biomaterials to bioengineered chemistries, and biomaterial devices that will significantly advance our ability to address patient needs and also to create new market opportunities. PMID:21171147
Intraoral gothic arch tracing.
Rubel, Barry; Hill, Edward E
2011-01-01
In order to create optimum esthetics, function and phonetics in complete denture fabrication, it is necessary to record accurate maxillo-mandibular determinants of occlusion. This requires clinical skill to establish an accurate, verifiable and reproducible vertical dimension of occlusion (VDO) and centric relation (CR). Correct vertical relation depends upon a consideration of several factors, including muscle tone, inter-dental arch space and parallelism of the ridges. Any errors made while taking maxillo-mandibular jaw relation records will result in dentures that are uncomfortable and, possibly, unwearable. The application of a tracing mechanism such as the Gothic arch tracer (a central bearing device) is a demonstrable method of determining centric relation. Intraoral Gothic arch tracers provide the advantage of capturing VDO and CR in an easy-to-use technique for practitioners. Intraoral tracing (Gothic arch tracing) is a preferred method of obtaining consistent positions of the mandible in motion (retrusive, protrusive and lateral) at a comfortable VDO.
International Nuclear Information System (INIS)
Raoelina Andriambololona; Ranaivoson, R.T.R.; Rakotoson, H.; Solofoarisina, W.C.
2015-04-01
We present a study on linear canonical transformation in the framework of a phase space representation of quantum mechanics that we have introduced in our previous work. We begin with a brief recall about the so called phase space representation. We give the definition of linear canonical transformation with the transformation law of coordinate and momentum operators. We establish successively the transformation laws of mean values, dispersions, basis state and wave functions.Then we introduce the concept of isodispersion linear canonical transformation.
Majoros, Andrea; Platanitis, Ekaterini; Kernbauer-Hölzl, Elisabeth; Rosebrock, Felix; Müller, Mathias; Decker, Thomas
2017-01-01
Janus kinase (JAK)-signal transducer and activator of transcription (STAT) signal transduction mediates cytokine responses. Canonical signaling is based on STAT tyrosine phosphorylation by activated JAKs. Downstream of interferon (IFN) receptors, activated JAKs cause the formation of the transcription factors IFN-stimulated gene factor 3 (ISGF3), a heterotrimer of STAT1, STAT2 and interferon regulatory factor 9 (IRF9) subunits, and gamma interferon-activated factor (GAF), a STAT1 homodimer. In recent years, several deviations from this paradigm were reported. These include kinase-independent JAK functions as well as extra- and intranuclear activities of U-STATs without phosphotyrosines. Additionally, transcriptional control by STAT complexes resembling neither GAF nor ISGF3 contributes to transcriptome changes in IFN-treated cells. Our review summarizes the contribution of non-canonical JAK-STAT signaling to the innate antimicrobial immunity imparted by IFN. Moreover, we touch upon functions of IFN pathway proteins beyond the IFN response. These include metabolic functions of IRF9 as well as the regulation of natural killer cell activity by kinase-dead TYK2 and different phosphorylation isoforms of STAT1.
Majoros, Andrea; Platanitis, Ekaterini; Kernbauer-Hölzl, Elisabeth; Rosebrock, Felix; Müller, Mathias; Decker, Thomas
2017-01-01
Janus kinase (JAK)–signal transducer and activator of transcription (STAT) signal transduction mediates cytokine responses. Canonical signaling is based on STAT tyrosine phosphorylation by activated JAKs. Downstream of interferon (IFN) receptors, activated JAKs cause the formation of the transcription factors IFN-stimulated gene factor 3 (ISGF3), a heterotrimer of STAT1, STAT2 and interferon regulatory factor 9 (IRF9) subunits, and gamma interferon-activated factor (GAF), a STAT1 homodimer. In recent years, several deviations from this paradigm were reported. These include kinase-independent JAK functions as well as extra- and intranuclear activities of U-STATs without phosphotyrosines. Additionally, transcriptional control by STAT complexes resembling neither GAF nor ISGF3 contributes to transcriptome changes in IFN-treated cells. Our review summarizes the contribution of non-canonical JAK–STAT signaling to the innate antimicrobial immunity imparted by IFN. Moreover, we touch upon functions of IFN pathway proteins beyond the IFN response. These include metabolic functions of IRF9 as well as the regulation of natural killer cell activity by kinase-dead TYK2 and different phosphorylation isoforms of STAT1. PMID:28184222
International Nuclear Information System (INIS)
Samarzija, Ivana; Sini, Patrizia; Schlange, Thomas; MacDonald, Gwen; Hynes, Nancy E.
2009-01-01
Untangling the signaling pathways involved in endothelial cell biology is of central interest for the development of antiangiogenesis based therapies. Here we report that Wnt3a induces the proliferation and migration of HUVECs, but does not affect their survival. Wnt3a-induced proliferation was VEGFR signaling independent, but reduced upon CamKII inhibition. In a search for the downstream mediators of Wnt3a's effects on HUVEC biology, we found that Wnt3a treatment leads to phosphorylation of DVL3 and stabilization of β-catenin. Moreover, under the same conditions we observed an upregulation in c-MYC, TIE-2 and GJA1 mRNA transcripts. Although treatment of HUVECs with Wnt5a induced DVL3 phosphorylation, we did not observe any of the other effects seen upon Wnt3a stimulation. Taken together, our data indicate that Wnt3a induces canonical and non-canonical Wnt signaling in HUVECs, and stimulates their proliferation and migration.
Energy Technology Data Exchange (ETDEWEB)
Lu, Z.-T.; Bailey, K.; Chen, C.-Y.; Du, X.; Li, Y.-M.; O' Connor, T. P.; Young, L.
2000-05-25
A new method of ultrasensitive trace-isotope analysis has been developed based upon the technique of laser manipulation of neutral atoms. It has been used to count individual {sup 85}Kr and {sup 81}Kr atoms present in a natural krypton sample with isotopic abundances in the range of 10{sup {minus}11} and 10{sup {minus}13}, respectively. The atom counts are free of contamination from other isotopes, elements,or molecules. The method is applicable to other trace-isotopes that can be efficiently captured with a magneto-optical trap, and has a broad range of potential applications.
International Nuclear Information System (INIS)
Lu, Z.-T.; Bailey, K.; Chen, C.-Y.; Du, X.; Li, Y.-M.; O'Connor, T. P.; Young, L.
2000-01-01
A new method of ultrasensitive trace-isotope analysis has been developed based upon the technique of laser manipulation of neutral atoms. It has been used to count individual 85 Kr and 81 Kr atoms present in a natural krypton sample with isotopic abundances in the range of 10 -11 and 10 -13 , respectively. The atom counts are free of contamination from other isotopes, elements,or molecules. The method is applicable to other trace-isotopes that can be efficiently captured with a magneto-optical trap, and has a broad range of potential applications
Canonic FFT flow graphs for real-valued even/odd symmetric inputs
Lao, Yingjie; Parhi, Keshab K.
2017-12-01
Canonic real-valued fast Fourier transform (RFFT) has been proposed to reduce the arithmetic complexity by eliminating redundancies. In a canonic N-point RFFT, the number of signal values at each stage is canonic with respect to the number of signal values, i.e., N. The major advantage of the canonic RFFTs is that these require the least number of butterfly operations and only real datapaths when mapped to architectures. In this paper, we consider the FFT computation whose inputs are not only real but also even/odd symmetric, which indeed lead to the well-known discrete cosine and sine transforms (DCTs and DSTs). Novel algorithms for generating the flow graphs of canonic RFFTs with even/odd symmetric inputs are proposed. It is shown that the proposed algorithms lead to canonic structures with N/2 +1 signal values at each stage for an N-point real even symmetric FFT (REFFT) or N/2 -1 signal values at each stage for an N-point RFFT real odd symmetric FFT (ROFFT). In order to remove butterfly operations, several twiddle factor transformations are proposed in this paper. We also discuss the design of canonic REFFT for any composite length. Performances of the canonic REFFT/ROFFT are also discussed. It is shown that the flow graph of canonic REFFT/ROFFT has less number of interconnections, less butterfly operations, and less twiddle factor operations, compared to prior works.
Oscilloscope trace photograph digitizing system (TRACE)
International Nuclear Information System (INIS)
Richards, M.; Dabbs, R.D.
1977-10-01
The digitizing system allows digitization of photographs or sketches of waveforms and then the computer is used to reduce and analyze the data. The software allows for alignment, calibration, removal of baselines, removal of unwanted points and addition of new points which makes for a fairly versatile system as far as data reduction and manipulation are concerned. System considerations are introduced first to orient the potential user to the process of digitizing information. The start up and actual commands for TRACE are discussed. Detailed descriptions of each subroutine and program section are also provided. Three general examples of typical photographs are included. A partial listing of FAWTEK is made available. Once suitable arrays that contain the data are arranged, ''GO FA'' (active FAWTEK) and many mathematical operations to further analyze the data may be performed
Effective Higgs theories in supersymmetric grand unification
Energy Technology Data Exchange (ETDEWEB)
Zheng, Sibo [Chongqing University, Department of Physics, Chongqing (China)
2017-09-15
The effective Higgs theories at the TeV scale in supersymmetric SU(5) grand unification models are systematically derived. Restricted to extensions on 5{sub H} containing the Higgs sector we show that only two types of real (vector-like) models and one type of chiral model are found to be consistent with perturbative grand unification. While the chiral model has been excluded by the LHC data, the fate of perturbative unification will be uniquely determined by the two classes of vector-like models. (orig.)
Grand Tour: immaginario, territorio e culture digitali
Directory of Open Access Journals (Sweden)
Emiliano Ilardi
2016-12-01
Full Text Available Il Grand Tour può essere recuperato come asset narrativo utile per un intervento strategico di re-branding del viaggio in Italia? Il contributo analizza il contesto e le condizioni per una progettazione di questo livello nell’ambiente culturale dell’epoca digitale. Considerando gli archetipi moderni della mediazione dei luoghi come una grande riserva di senso, da riattivare sia nelle pratiche basate sui format seriali e transmediali che valorizzano i territori nella produzione creativa, sia nella costruzione di infrastrutture digitali e transluoghi per la valorizzazione degli attrattori culturali.
A Unified Grand Tour of Theoretical Physics
Lawrie, Ian D
2002-01-01
A unified account of the principles of theoretical physics, A Unified Grand Tour of Theoretical Physics, Second Edition stresses the inter-relationships between areas that are usually treated as independent. The profound unifying influence of geometrical ideas, the powerful formal similarities between statistical mechanics and quantum field theory, and the ubiquitous role of symmetries in determining the essential structure of physical theories are emphasized throughout.This second edition conducts a grand tour of the fundamental theories that shape our modern understanding of the physical wor
Canonical formulations of full nonlinear topologically massive gravity
International Nuclear Information System (INIS)
Deser, S.; Xiang, X.
1991-01-01
First-order forms of the complete nonlinear Einstein plus Chern-Simons third-derivative-order action are exhibited in both metric and dreibein forms. The 'hamiltonians' are combinations of diffeomorphism and tangent space rotation generators as expected of generally covariant systems; the pure Chern-Simons hamiltonian has an additional, conformal transformation, term. These constraints reduce the apparent number of degrees of freedom to 1 and 0 respectively. The constraint algebras close, as required by this counting, without second-class constraints. The nature of the noninvariant terms in the Chern-Simons lagrangian density is discussed. For comparison, the linearized limit and the corresponding nonabelian vector action's canonical form are also given. (orig.)
Optimization on scoliosis examination on Canons DR system
DEFF Research Database (Denmark)
Precht, Helle
2007-01-01
recordings of scoliosis today are carried out on CR systems even though most radiological departments have DR systems available. Theoretically speaking the two modalities are similar regarding dose and image quality. In this project consequently, the focus will be to obtain images of equal dose and quality...... at a DR system when using different receptors during the exam. This is a completely new opportunity, as it has earlier been difficult to compare distinct scintilators connected to the receptors due to unlike processing of the image. Given that Canon have released a receptor with CsI scintilator we...... in which theory is used as a background for the test setup and later audit appraisal. Two tests are carried out on two different hospitals with each their receptor, and afterwards the results are compared. To guarantee comparable tests the results are verified through status checks and statistical t...
Garcilaso y Cervantes en la perspectiva del canon
Directory of Open Access Journals (Sweden)
Pablo Gálvez
2015-06-01
Full Text Available Este ensayo examina de modo sucinto la relación entre la obra de Miguel de Cervantes, en especial el Quijote, y la poesía de Garcilaso de la Vega en el horizonte de los valores consagrados en el canon literario de los Siglos de Oro. Para ello, primeramente se ofrece una breve semblanza biográfica e intelectual que busca establecer similitudes entre ambos autores; en segundo lugar, el texto registra diversas apariciones o “señales” garcilasianas en las páginas de la novela en sus dos partes (1605 y 1615 y las comenta con una visión al mismo tiempo crítica e histórica. El trabajo procura hacer una contribución sobre modos nuevos de analizar la tradición literaria y presta la mayor atención a las ideas cervantinas sobre la poesía.
New Inequalities and Uncertainty Relations on Linear Canonical Transform Revisit
Directory of Open Access Journals (Sweden)
Xu Guanlei
2009-01-01
Full Text Available The uncertainty principle plays an important role in mathematics, physics, signal processing, and so on. Firstly, based on definition of the linear canonical transform (LCT and the traditional Pitt's inequality, one novel Pitt's inequality in the LCT domains is obtained, which is connected with the LCT parameters a and b. Then one novel logarithmic uncertainty principle is derived from this novel Pitt's inequality in the LCT domains, which is associated with parameters of the two LCTs. Secondly, from the relation between the original function and LCT, one entropic uncertainty principle and one Heisenberg's uncertainty principle in the LCT domains are derived, which are associated with the LCT parameters a and b. The reason why the three lower bounds are only associated with LCT parameters a and b and independent of c and d is presented. The results show it is possible that the bounds tend to zeros.
Canonical momenta and numerical instabilities in particle codes
International Nuclear Information System (INIS)
Godfrey, B.B.
1975-01-01
A set of warm plasma dispersion relations appropriate to a large class of electromagnetic plasma simulation codes is derived. The numerical Cherenkov instability is shown by analytic and numerical analysis of these dispersion relations to be the most significant nonphysical effect involving transverse electromagnetic waves. The instability arises due to a spurious phase shift between resonant particles and light waves, caused by a basic incompatibility between the Lagrangian treatment of particle positions and the Eulerian treatment of particle velocities characteristic of most PIC--CIC algorithms. It is demonstrated that, through the use of canonical momentum, this mismatch is alleviated sufficiently to completely eliminate the Cherenkov instability. Collateral effects on simulation accuracy and on other numerical instabilities appear to be minor
The canonical Lagrangian approach to three-space general relativity
Shyam, Vasudev; Venkatesh, Madhavan
2013-07-01
We study the action for the three-space formalism of general relativity, better known as the Barbour-Foster-Ó Murchadha action, which is a square-root Baierlein-Sharp-Wheeler action. In particular, we explore the (pre)symplectic structure by pulling it back via a Legendre map to the tangent bundle of the configuration space of this action. With it we attain the canonical Lagrangian vector field which generates the gauge transformations (3-diffeomorphisms) and the true physical evolution of the system. This vector field encapsulates all the dynamics of the system. We also discuss briefly the observables and perennials for this theory. We then present a symplectic reduction of the constrained phase space.
Canonical statistics of trapped ideal and interacting Bose gases
International Nuclear Information System (INIS)
Xiong Hongwei; Liu Shujuan; Huang Guoxiang; Xu Zaixin
2002-01-01
The mean ground-state occupation number and condensate fluctuations of interacting and noninteracting Bose gases confined in a harmonic trap are considered by using a canonical ensemble approach. To obtain the mean ground-state occupation number and the condensate fluctuations, an analytical description for the probability distribution function of the condensate is provided directly starting from the analysis of the partition function of the system. For the ideal Bose gas, the probability distribution function is found to be a Gaussian one for the case of the harmonic trap. For the interacting Bose gas, using a unified approach the condensate fluctuations are calculated based on the lowest-order perturbation method and on Bogoliubov theory. It is found that the condensate fluctuations based on the lowest-order perturbation theory follow the law 2 N 0 >∼N, while the fluctuations based on Bogoliubov theory behave as N 4/3
Canonical quantization of a relativistic particle with curvature and torsion
International Nuclear Information System (INIS)
Nesterenko, V.V.
1991-01-01
A generalization of the relativistic particle action is considered. It contain, in addition to the length of the world trajectory, the integrals along the world curve of its curvature and torsion. The generalized Hamiltonian formalism for this model in the D-dimensional space-time is constructed. A complete set of the constraints in the phase space is obtained and their division into the first-class and the second-class constraints is accomplished. On this basis the canonical quantization of the model is fulfilled. For D=3 the mass spectrum is obtained in the sector without tachyonic states, the mass of the state being dependent on its spin. It is shown that in the framework of this model when D=3 the possibility to describe the states with integral, half-odd-integral and continuous spins is derived. Interaction with an external Abelian gauge field introduced in the geometrical way. 21 refs
Successive canonical transformation in model two-body electrodynamics
International Nuclear Information System (INIS)
Raha, S.
1978-10-01
The possibility is investigated of bypassing the no interaction theorum of Currie, Jordan and Sudarshan for direct action Lagrangians. Starting with the field theoretic description of a two-body electrodynamic problem, the field variable is solved for in terms of the particle variables, which paves the way to write an action-at-a-distance Hamiltonian for the problem. A suitable transformation is found which uncouples the field and the particle variables in the interaction up to order e 2 . It is shown that this transformation leaves the statement of Newton's 2nd law unchanged which also agrees with the standard results of electrodynamics. This allows for the identification of canonical variables for the proper action-at-a-distance problem. 19 references
DEFF Research Database (Denmark)
Balle, Søren Hattesen
as (re)tracings of genres that appear somehow residual or defunct in a post-modernist poetic context. On the other, they are made to "encode new [and queer, shb] meanings" (Anne Ferry) inasmuch as Ashbery, for instance, doubles and literalizes Dante's false etymology of the word ‘eclogue' (aig- and logos...
DEFF Research Database (Denmark)
Samson, Kristine; Abasolo, José
2013-01-01
The city and its public spaces can be seen as a fragmented whole carrying meanings and traces of culture, use and politics with it. Whereas architects impose new stories and meanings on the urban fabric, the city itself is layered and assembled, a collective of social flows and routines a result ...
Indian Academy of Sciences (India)
N. Centre for Advanced Scientific Research, Bangalore 560 064, India. 2Indian Institute of ... for rational functions φ with poles off R. In [5,16], Koplienko's trace formula was derived ... be a sequence of complex numbers such that ..... Again if we set the sum of the second and fourth term inside the integral in (2.3) to be. I2 ≡.
Variations in Canonical Star-Forming Laws at Low Metallicity
Monkiewicz, Jacqueline; Bowman, Judd D.; Scowen, Paul
2018-01-01
Empirically-determined star formation relations link observed galaxy luminosities to extrapolated star formation rates at almost every observable wavelength range. These laws are a cornerstone of extragalactic astronomy, and will be critically important for interpreting upcoming observations of early high-redshift protogalaxies with JWST and WFIRST. There are indications at a variety of wavelengths that these canonical relations may become unreliable at the lowest metallicities observed. This potentially complicates interpretation of the earliest protogalaxies, which are expected to be pristine and largely unenriched by stellar nucleosynthesis. Using a sample of 15 local dwarf galaxies with 12+[O/H] dwarf galaxies 1 Zw 18 and SBS 0335-052E suggest that the far-IR/radio relation probably deviates at low metallicities, but the low luminosity end of the relation is not well sampled. The upgraded Jansky Very Large Array has the sensitivity to fill in this gap. I have obtained 45 hours of L- and C-band continuum data of my dwarf galaxy sample. I present radio continuum imaging of an initial sub-sample of Local Group dwarfs, some of which have never before been detected in radio continuum. The H-alpha/UV relationship is likewise known to become unreliable for dwarf galaxies, though this has been attributed to dwarf galaxy "bursty-ness" rather than metallicity effects. I have conducted a parallel survey of emission line imaging to study the underlying astrophysics of the H-alpha/UV relation. Using Balmer decrement imaging, I map out the pixel-to-pixel dust distribution and geometry within the nearest galaxies in my sample. I compare this to GALEX UV imaging. I discuss implications for UV escape fraction, and present initial results of the canonical star-forming relations at low galaxy luminosity and metallicity. THIS IS A POSTER AND WILL BE LOCATED IN THE AAS BOOTH.
Intersubject information mapping: revealing canonical representations of complex natural stimuli
Directory of Open Access Journals (Sweden)
Nikolaus Kriegeskorte
2015-03-01
Full Text Available Real-world time-continuous stimuli such as video promise greater naturalism for studies of brain function. However, modeling the stimulus variation is challenging and introduces a bias in favor of particular descriptive dimensions. Alternatively, we can look for brain regions whose signal is correlated between subjects, essentially using one subject to model another. Intersubject correlation mapping (ICM allows us to find brain regions driven in a canonical manner across subjects by a complex natural stimulus. However, it requires a direct voxel-to-voxel match between the spatiotemporal activity patterns and is thus only sensitive to common activations sufficiently extended to match up in Talairach space (or in an alternative, e.g. cortical-surface-based, common brain space. Here we introduce the more general approach of intersubject information mapping (IIM. For each brain region, IIM determines how much information is shared between the subjects' local spatiotemporal activity patterns. We estimate the intersubject mutual information using canonical correlation analysis applied to voxels within a spherical searchlight centered on each voxel in turn. The intersubject information estimate is invariant to linear transforms including spatial rearrangement of the voxels within the searchlight. This invariance to local encoding will be crucial in exploring fine-grained brain representations, which cannot be matched up in a common space and, more fundamentally, might be unique to each individual – like fingerprints. IIM yields a continuous brain map, which reflects intersubject information in fine-grained patterns. Performed on data from functional magnetic resonance imaging (fMRI of subjects viewing the same television show, IIM and ICM both highlighted sensory representations, including primary visual and auditory cortices. However, IIM revealed additional regions in higher association cortices, namely temporal pole and orbitofrontal cortex. These
Multi-dimensional virtual system introduced to enhance canonical sampling
Higo, Junichi; Kasahara, Kota; Nakamura, Haruki
2017-10-01
When an important process of a molecular system occurs via a combination of two or more rare events, which occur almost independently to one another, computational sampling for the important process is difficult. Here, to sample such a process effectively, we developed a new method, named the "multi-dimensional Virtual-system coupled Monte Carlo (multi-dimensional-VcMC)" method, where the system interacts with a virtual system expressed by two or more virtual coordinates. Each virtual coordinate controls sampling along a reaction coordinate. By setting multiple reaction coordinates to be related to the corresponding rare events, sampling of the important process can be enhanced. An advantage of multi-dimensional-VcMC is its simplicity: Namely, the conformation moves widely in the multi-dimensional reaction coordinate space without knowledge of canonical distribution functions of the system. To examine the effectiveness of the algorithm, we introduced a toy model where two molecules (receptor and its ligand) bind and unbind to each other. The receptor has a deep binding pocket, to which the ligand enters for binding. Furthermore, a gate is set at the entrance of the pocket, and the gate is usually closed. Thus, the molecular binding takes place via the two events: ligand approach to the pocket and gate opening. In two-dimensional (2D)-VcMC, the two molecules exhibited repeated binding and unbinding, and an equilibrated distribution was obtained as expected. A conventional canonical simulation, which was 200 times longer than 2D-VcMC, failed in sampling the binding/unbinding effectively. The current method is applicable to various biological systems.
The canonical status of Constantinople and its interpretation in Byzantium
Directory of Open Access Journals (Sweden)
Pavel Kuzenkov
2015-06-01
Full Text Available The author subjects to thorough consideration the gradual change in the status of the Patriarch of Constantinople from the bishop of a minor town to the Ecumenical Patriarch possessing a certain set of administrative privileges. After giving a deﬁnition of the status of a bishop and ecclesiastical provinces in the ancient Church, the author, basing his conclusions upon canonical sources and their expositions in the Early Byzantine period, proceeds to develop the idea that the change in the bishop’s status went through several successive stages and that each new stage had its own causes, not the least important of which were of political nature. After both Rome and Constantinople, as political centers of the Roman Empire, received in the 4th century certain «privileges of honor» peculiar to capital cities, these privileges were consecutively modiﬁed into mandate of power. This process took several centuries to reach completion and was connected with the activities of the Emperors Zeno I and Justinian the Great (5th–6th centuries who legally secured the new status of the bishop of the capital city and granted him the title of Ecumenical Patriarch. After the patriarchate of Photius and the conﬂ ict with the bishops of Rome the Patriarch of Constantinople receives the right to intrude — in certain cases — into the canonical jurisdiction of other Churches, which becomes the key change in understanding the nature of supremacy. In later times this tendency was enhanced and reached its climax in the 20th century when the Ecumenical Patriarchate began testing the ground to expand its authority to the whole of the Orthodox world, with the further perspective of turning into a kind of «Orthodox Rome».
Did a slump source cause the 1929 Grand Banks tsunami?
Løvholt, F.; Schulten, I.; Mosher, D.; Harbitz, C. B.; Krastel, S.
2017-12-01
On November 18, 1929, a Mw 7.2 earthquake occurred beneath the upper Laurentian Fan, south of Newfoundland. The earthquake displaced about 100 km3 of sediment volume that rapidly evolved into a turbidity current revealed by a series of successive telecommunication cable breaks. A tsunami with fatal consequences along the south coast of Newfoundland also resulted. This tsunami is attributed to sediment mass failure as no seafloor displacement due to the earthquake is observed or expected. Although sidescan sonar, sub-bottom profiler and modern multibeam data show surficial sediment slumping and translational slide activity in the upper part of the slope, no major headscarp, single evacuation area or large mass transport deposit are observed. Sediment mass failure has been interpreted as broadly distributed and shallow, likely occurring in a retrogressive fashion. The question remained, therefore, as to how such complex failure kinematics could generate a tsunami. The Grand Banks tsunami is the only landslide tsunami for which traces are found at transoceanic distances. Despite being a landmark event, only a couple of attempts to model the tsunami exist. None of these have been able to match tsunami observations. Recently acquired seismic reflection data suggest that rotational slumping of a thick sediment mass ( 500 m) on the St. Pierre Slope may have occurred, causing seafloor displacements (fault traces) up to 100 m in height. The previously mapped surficial failures were a consequence of slumping of the thicker mass. Here, we simulate tsunami generation using the new geophysical information to construct different tsunamigenic slump sources. In addition, we undertake simulations assuming a flowing surficial landslide. The numerical simulations shows that its large and rapid vertical displacements render the slump source more tsunamigenic than the alternative surficial landslide. The simulations using the slump source roughly complies with observations of large run
Jacobs, Glenn
2009-01-01
This analysis assesses the factors underlying Charles Horton Cooley's place in the sociological canon as they relate to George Herbert Mead's puzzling diatribe-echoed in secondary accounts-against Cooley's social psychology and view of the self published scarcely a year after his death. The illocutionary act of publishing his critique stands as an effort to project the image of Mead's intellectual self and enhance his standing among sociologists within and outside the orbit of the University of Chicago. It expressed Mead's ambivalence toward his precursor Cooley, whose influence he never fully acknowledged. In addition, it typifies the contending fractal distinctions of the scientifically discursive versus literary styles of Mead and Cooley, who both founded the interpretive sociological tradition. The contrasting styles and attitudes toward writing of the two figures are discussed, and their implications for the problems of scale that have stymied the symbolic interactionist tradition are explored.
Poisson traces, D-modules, and symplectic resolutions.
Etingof, Pavel; Schedler, Travis
2018-01-01
We survey the theory of Poisson traces (or zeroth Poisson homology) developed by the authors in a series of recent papers. The goal is to understand this subtle invariant of (singular) Poisson varieties, conditions for it to be finite-dimensional, its relationship to the geometry and topology of symplectic resolutions, and its applications to quantizations. The main technique is the study of a canonical D-module on the variety. In the case the variety has finitely many symplectic leaves (such as for symplectic singularities and Hamiltonian reductions of symplectic vector spaces by reductive groups), the D-module is holonomic, and hence, the space of Poisson traces is finite-dimensional. As an application, there are finitely many irreducible finite-dimensional representations of every quantization of the variety. Conjecturally, the D-module is the pushforward of the canonical D-module under every symplectic resolution of singularities, which implies that the space of Poisson traces is dual to the top cohomology of the resolution. We explain many examples where the conjecture is proved, such as symmetric powers of du Val singularities and symplectic surfaces and Slodowy slices in the nilpotent cone of a semisimple Lie algebra. We compute the D-module in the case of surfaces with isolated singularities and show it is not always semisimple. We also explain generalizations to arbitrary Lie algebras of vector fields, connections to the Bernstein-Sato polynomial, relations to two-variable special polynomials such as Kostka polynomials and Tutte polynomials, and a conjectural relationship with deformations of symplectic resolutions. In the appendix we give a brief recollection of the theory of D-modules on singular varieties that we require.
Poisson traces, D-modules, and symplectic resolutions
Etingof, Pavel; Schedler, Travis
2018-03-01
We survey the theory of Poisson traces (or zeroth Poisson homology) developed by the authors in a series of recent papers. The goal is to understand this subtle invariant of (singular) Poisson varieties, conditions for it to be finite-dimensional, its relationship to the geometry and topology of symplectic resolutions, and its applications to quantizations. The main technique is the study of a canonical D-module on the variety. In the case the variety has finitely many symplectic leaves (such as for symplectic singularities and Hamiltonian reductions of symplectic vector spaces by reductive groups), the D-module is holonomic, and hence, the space of Poisson traces is finite-dimensional. As an application, there are finitely many irreducible finite-dimensional representations of every quantization of the variety. Conjecturally, the D-module is the pushforward of the canonical D-module under every symplectic resolution of singularities, which implies that the space of Poisson traces is dual to the top cohomology of the resolution. We explain many examples where the conjecture is proved, such as symmetric powers of du Val singularities and symplectic surfaces and Slodowy slices in the nilpotent cone of a semisimple Lie algebra. We compute the D-module in the case of surfaces with isolated singularities and show it is not always semisimple. We also explain generalizations to arbitrary Lie algebras of vector fields, connections to the Bernstein-Sato polynomial, relations to two-variable special polynomials such as Kostka polynomials and Tutte polynomials, and a conjectural relationship with deformations of symplectic resolutions. In the appendix we give a brief recollection of the theory of D-modules on singular varieties that we require.
Hilbert's Grand Hotel with a series twist
Wijeratne, Chanakya; Mamolo, Ami; Zazkis, Rina
2014-08-01
This paper presents a new twist on a familiar paradox, linking seemingly disparate ideas under one roof. Hilbert's Grand Hotel, a paradox which addresses infinite set comparisons is adapted and extended to incorporate ideas from calculus - namely infinite series. We present and resolve several variations, and invite the reader to explore his or her own variations.
"Teine" võitis Prantsusmaal Grand Prix'
2006-01-01
Prantsusmaal Essonne'is toimuval 8. Euroopa filmifestivalil Cinessonne sai üliõpilaste žürii grand prix rahvusvahelises ühistöös valminud tantsufilm "Teine" ("Another") : režissöör Rene Vilbre. Ka teistest festivalidest, kus film osalenud
The Virtual Grand Tour as Educational Paradigm
DEFF Research Database (Denmark)
Hansen, Per Skafte; Mouritsen, Lars
2001-01-01
The Virtual Grand Tour as defined here bears some resemblance to its 18th century ancestor: a wide range of individual topics are treated as a whole; a tutor, whether real or simulated, present or remote, is provided; a set of problem solving tools forms an integrated part of the "traveller...
Grand Prix Eurovision: Eine Fankultur im Medienzeitalter
Directory of Open Access Journals (Sweden)
Heinz Moser
2017-06-01
Full Text Available Der Grand Prix Eurovision ist seit Jahrzehnten eine der bekanntesten Unterhaltungssendungen im europäischen Raum. Dennoch erregte es Verwunderung, wenn der Schreibende Bekannten darüber berichtete, daß dies ein Forschungsgegenstand sei. Wurde von Interviews mit Grand Prix-Fans erzählt, so fielen schnell Aussagen wie: „Wie kann man sich nur für so etwas Abseitiges und Triviales wie den Grand Prix interessieren“. Dennoch bin ich der Meinung, daß Fankulturen für die entstehende Mediengesellschaft ein nicht unwichtiges Forschungsthema darstellen. Zwar geht es nicht um eine medienpädagogische Fragestellung im engeren Sinne; die Fans des Grand Prix Eurovision sind dem Jugendalter längst entwachsen. Dennoch handelt es sich bei Fangemeinschaften um Phänomene, die im Rahmen von Jugend- und Kinderkulturen von besonderer Relevanz sind. So meint Winter (1997, daß jugendliche Fanwelten eine bedeutende Rolle als Kristallisationspunkte kultureller Differenzierung spielen: ,Die Zugehörigkeit zu einer Fan weit ist Teil der jugendlichen Lebensbewältigung in der Postmoderne, denn in der Gemeinschaft der Fans können Jugendliche emotionale Allianzen eingehen, außeralltäglichen Beschäftigungen nachgehen, expressive Identitätsmuster gemeinschaftlich realisieren und sich mit ihrer Lebenssituation als Heranwachsende auseinandersetzen“ (Winter 1997, S. 51f..
Grand Canyon Monitoring and Research Center
Hamill, John F.
2009-01-01
The Grand Canyon of the Colorado River, one of the world's most spectacular gorges, is a premier U.S. National Park and a World Heritage Site. The canyon supports a diverse array of distinctive plants and animals and contains cultural resources significant to the region's Native Americans. About 15 miles upstream of Grand Canyon National Park sits Glen Canyon Dam, completed in 1963, which created Lake Powell. The dam provides hydroelectric power for 200 wholesale customers in six western States, but it has also altered the Colorado River's flow, temperature, and sediment-carrying capacity. Over time this has resulted in beach erosion, invasion and expansion of nonnative species, and losses of native fish. Public concern about the effects of Glen Canyon Dam operations prompted the passage of the Grand Canyon Protection Act of 1992, which directs the Secretary of the Interior to operate the dam 'to protect, mitigate adverse impacts to, and improve values for which Grand Canyon National Park and Glen Canyon National Recreation Area were established...' This legislation also required the creation of a long-term monitoring and research program to provide information that could inform decisions related to dam operations and protection of downstream resources.
Comprehensive District Reform: Philadelphia's Grand Experiment.
Useem, Elizabeth; Balfanz, Robert
2002-01-01
This report describes "Philadelphia's Grand Experiment" in comprehensive school district reform, from its conception through its initial months of implementation. In 2001, as part of the remedy for low student performance, the governor ordered the state to take over governance of the Philadelphia School District, with a substantial…
Rio Branco, grand strategy and naval power
Directory of Open Access Journals (Sweden)
João Paulo Alsina Jr.
2014-12-01
Full Text Available This article addresses Baron of Rio Branco's grand strategy and the role played by the naval reorganization program (1904-1910 in this context. The ensuing case study determined the domestic and international constraints that affected the program, as well as the worldview of the patron of Brazilian diplomacy regarding military power's instrumentality to foreign policy.
Reisipakkumine - Grand Tour Itaalias / Mai Levin
Levin, Mai, 1942-
2009-01-01
Tiina Abeli koostatud ja Urmas Viigi kujundatud näitus "Grand Tour. Eesti kunstnikud Itaalias" Kumu Kunstimuuseumis 05. aprillini. Loetletud eksponeeritud tööde autoreid. Näitus annab ülevaate, kes siinsetest kunstnikest 19. sajandi algusest kuni 1930ndate aastateni Itaalias käisid ja kuidas see nende loomingut mõjutas
Middle Rio Grande Basin Research Report 2008
Deborah M. Finch; Catherine Dold
2008-01-01
An ecosystem is rarely static. A natural system composed of plants, animals, and microorganisms interacting with an area's physical factors, an ecosystem is always fluctuating and evolving. But sometimes, often at the hands of humans, ecosystems change too much. Such is the case with many of the ecosystems of the Middle Rio Grande Basin of New Mexico.
Panel - Rio Grande restoration: Future directions
Deborah M. Finch; Pete V. Domenici; Jeffrey. C. Whitney; Steve Harris; Brian Shields; Clifford S. Crawford
1996-01-01
The purpose of this panel was to discuss historical and current changes to the Rio Grande system, focusing on the middle Basin, and to present and review different individual, organizational, and political perspectives on the future of the system. Invitations were made to panelists based on their past and current interests and activities pertaining to restoration of...
A Canonical Response in Rainfall Characteristics to Global Warming: Projections by IPCC CMIP5 Models
Lau, William K. M.; Wu, H. T.; Kim, K. M.
2012-01-01
Changes in rainfall characteristics induced by global warming are examined based on probability distribution function (PDF) analysis, from outputs of 14 IPCC (Intergovernmental Panel on Climate Change), CMIP (5th Coupled Model Intercomparison Project) models under various scenarios of increased CO2 emissions. Results show that collectively CMIP5 models project a robust and consistent global and regional rainfall response to CO2 warming. Globally, the models show a 1-3% increase in rainfall per degree rise in temperature, with a canonical response featuring large increase (100-250 %) in frequency of occurrence of very heavy rain, a reduction (5-10%) of moderate rain, and an increase (10-15%) of light rain events. Regionally, even though details vary among models, a majority of the models (>10 out of 14) project a consistent large scale response with more heavy rain events in climatologically wet regions, most pronounced in the Pacific ITCZ and the Asian monsoon. Moderate rain events are found to decrease over extensive regions of the subtropical and extratropical oceans, but increases over the extratropical land regions, and the Southern Oceans. The spatial distribution of light rain resembles that of moderate rain, but mostly with opposite polarity. The majority of the models also show increase in the number of dry events (absence or only trace amount of rain) over subtropical and tropical land regions in both hemispheres. These results suggest that rainfall characteristics are changing and that increased extreme rainfall events and droughts occurrences are connected, as a consequent of a global adjustment of the large scale circulation to global warming.
2015-03-26
83 5.1 Marginal PMFs for the cylinder scene at coarse zoom. . . . . . . . . . . . . . . 85 5.2 SAR image of a Nissan Sentra with canonical...of a Nissan Sentra with canonical features extracted by the SPLIT algorithm. 5.2.4 Experiment Summary. A notional algorithm is presented in Figure 5.3
International Nuclear Information System (INIS)
Yeon, Kyu Hwang; Hong, Suc Kyoung; Um, Chung In; George, Thomas F.
2006-01-01
With quantum operators corresponding to functions of the canonical variables, Schroedinger equations are constructed for systems corresponding to classical systems connected by a general point canonical transformation. Using the operator connecting quantum states between systems before and after the transformation, the quantum correction term and ordering parameter are obtained
Non-canonical autophagy: an exception or an underestimated form of autophagy?
Scarlatti, Francesca; Maffei, Roberta; Beau, Isabelle; Ghidoni, Riccardo; Codogno, Patrice
2008-11-01
Macroautophagy (hereafter called autophagy) is a dynamic and evolutionarily conserved process used to sequester and degrade cytoplasm and entire organelles in a sequestering vesicle with a double membrane, known as the autophagosome, which ultimately fuses with a lysosome to degrade its autophagic cargo. Recently, we have unraveled two distinct forms of autophagy in cancer cells, which we term canonical and non-canonical autophagy. In contrast to classical or canonical autophagy, non-canonical autophagy is a process that does not require the entire set of autophagy-related (Atg) proteins in particular Beclin 1, to form the autophagosome. Non-canonical autophagy is therefore not blocked by the knockdown of Beclin 1 or of its binding partner hVps34. Moreover overexpression of Bcl-2, which is known to block canonical starvation-induced autophagy by binding to Beclin 1, is unable to reverse the non-canonical autophagy triggered by the polyphenol resveratrol in the breast cancer MCF-7 cell line. In MCF-7 cells, at least, non-canonical autophagy is involved in the caspase-independent cell death induced by resveratrol.
Formulation of nonlinear chromaticity in circular accelerators by canonical perturbation method
International Nuclear Information System (INIS)
Takao, Masaru
2005-01-01
The formulation of nonlinear chromaticity in circular accelerators based on the canonical perturbation method is presented. Since the canonical perturbation method directly relates the tune shift to the perturbation Hamiltonian, it greatly simplifies the calculation of the nonlinear chromaticity. The obtained integral representation for nonlinear chromaticity can be systematically extended to higher orders
Legg, Robert
2012-01-01
This article applies Bourdieu's notion of "cultural capital" to historical, documentary research which investigates the construction of a scholastic canon within England's A-level music examinations. A digest of the ways in which this canon evolved between 1951 and 1986 is presented in support of the idea that examiners' responses to…
Hamiltonian formalism, quantization and S matrix for supergravity. [S matrix, canonical constraints
Energy Technology Data Exchange (ETDEWEB)
Fradkin, E S; Vasiliev, M A [AN SSSR, Moscow. Fizicheskij Inst.
1977-12-05
The canonical formalism for supergravity is constructed. The algebra of canonical constraints is found. The correct expression for the S matrix is obtained. Usual 'covariant methods' lead to an incorrect S matrix in supergravity since a new four-particle interaction of ghostfields survives in the Lagrangian expression of the S matrix.
Generalized canonical analysis based on optimizing matrix correlations and a relation with IDIOSCAL
Kiers, Henk A.L.; Cléroux, R.; Ten Berge, Jos M.F.
1994-01-01
Carroll's method for generalized canonical analysis of two or more sets of variables is shown to optimize the sum of squared inner-product matrix correlations between a consensus matrix and matrices with canonical variates for each set of variables. In addition, the method that analogously optimizes
An algorithm to compute the canonical basis of an irreducible Uq(g)-module
de Graaf, W. A.
2002-01-01
An algorithm is described to compute the canonical basis of an irreducible module over a quantized enveloping algebra of a finite-dimensional semisimple Lie algebra. The algorithm works for modules that are constructed as a submodule of a tensor product of modules with known canonical bases.
Using Canonical Forms for Isomorphism Reduction in Graph-based Model Checking
Kant, Gijs
Graph isomorphism checking can be used in graph-based model checking to achieve symmetry reduction. Instead of one-to-one comparing the graph representations of states, canonical forms of state graphs can be computed. These canonical forms can be used to store and compare states. However, computing
International Nuclear Information System (INIS)
Singh, Parampreet; Soni, S K
2016-01-01
The problem of obtaining canonical Hamiltonian structures from the equations of motion, without any knowledge of the action, is studied in the context of the spatially flat Friedmann, ‘Robertson’, and Walker models. Modifications to the Raychaudhuri equation are implemented independently as quadratic and cubic terms of energy density without introducing additional degrees of freedom. Depending on their sign, modifications make gravity repulsive above a curvature scale for matter satisfying strong energy conditions, or more attractive than in the classical theory. The canonical structure of the modified theories is determined by demanding that the total Hamiltonian be a linear combination of gravity and matter Hamiltonians. In the quadratic repulsive case, the modified canonical phase space of gravity is a polymerized phase space with canonical momentum as inverse a trigonometric function of the Hubble rate; the canonical Hamiltonian can be identified with the effective Hamiltonian in loop quantum cosmology. The repulsive cubic modification results in a ‘generalized polymerized’ canonical phase space. Both the repulsive modifications are found to yield singularity avoidance. In contrast, the quadratic and cubic attractive modifications result in a canonical phase space in which canonical momentum is nontrigonometric and singularities persist. Our results hint at connections between the repulsive/attractive nature of modifications to gravity arising from the gravitational sector and polymerized/non polymerized gravitational phase space. (paper)
Wilson, Celia M.
2010-01-01
Research pertaining to the distortion of the squared canonical correlation coefficient has traditionally been limited to the effects of sampling error and associated correction formulas. The purpose of this study was to compare the degree of attenuation of the squared canonical correlation coefficient under varying conditions of score reliability.…
Canonical basis for type A4 (II) - Polynomial elements in one variable
International Nuclear Information System (INIS)
Hu Yuwang; Ye Jiachen
2003-12-01
All the 62 monomial elements in the canonical basis B of the quantized enveloping algebra for type A 4 have been determined. According to Lusztig's idea, the elements in the canonical basis B consist of monomials and linear combinations of monomials (for convenience, we call them polynomials). In this note, we compute all the 144 polynomial elements in one variable in the canonical basis B of the quantized enveloping algebra for type A 4 based on our joint note. We conjecture that there are other polynomial elements in two or three variables in the canonical basis B, which include independent variables and dependent variables. Moreover, it is conjectured that there are no polynomial elements in the canonical basis B with four or more variables. (author)
Ramírez Bellido, Alejandro; Larriba Pey, Josep; Valero Cortés, Mateo
2005-01-01
We explore the use of compiler optimizations, which optimize the layout of instructions in memory. The target is to enable the code to make better use of the underlying hardware resources regardless of the specific details of the processor/architecture in order to increase fetch performance. The Software Trace Cache (STC) is a code layout algorithm with a broader target than previous layout optimizations. We target not only an improvement in the instruction cache hit rate, but also an increas...
Indian Academy of Sciences (India)
In this note, we shall try to present an elemen- tary proof of a couple of closely related results which have both proved quite useful, and al~ indicate possible generalisations. The results we have in mind are the following facts: (a) A complex n x n matrix A has trace 0 if and only if it is expressible in the form A = PQ - Q P.
Preconcentration of trace elements
International Nuclear Information System (INIS)
Zolotov, Yu. A.; Kuz'min, N.M.
1990-01-01
This monograph deals with the theory and practical applications of trace metals preconcentration. It gives general characteristics of the process and describes in detail the methods of preconcentration: solvent extraction, sorption, co-precipitation, volatilization, and others. Special attention is given to preconcentration in combination with subsequent determination methods. The use of preconcentration in analysis of environmental and biological samples, mineral raw materials, high purity substances, and various industrial materials is also considered
Major and trace elements in geological samples from Itingussu Basin in Coroa-Grande, RJ
Energy Technology Data Exchange (ETDEWEB)
Araripe, Denise R. [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Inst. de Quimica. Dept. de Quimica Analitica; E-mail: drararipe@vm.uff.br; Bellido, Alfredo V.B.; Canesim, Fatima [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Inst. de Quimica. Dept. de Fisico-Quimica; Patchineelam, Sambasiva R.; Machdo, Edimar [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Dept. de Geoquimica; Bellido, Luis F. [Instituto de Engenharia Nuclear IEN, Rio de Janeiro, RJ (Brazil); Vasconcelos, Marina B.A. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)
2005-07-01
The goal of the present work was to characterize soil samples and sediment of mangrove belong the Itingussu river drainage basin, with a view to investigate the lithological signature of it. This small drainage ends in area not yet largely impacted by other sources such as industrial and domestic waste in relation to the elements studied here. The results showed some enrichment of the U,Th and some light rare earth elements in the Itingussu sediment sample. This represent the leucocratic rock signature, according to the normalized of data by upper crustal mean values . (author)
Major and trace elements in geological samples from Itingussu Basin in Coroa-Grande, RJ
International Nuclear Information System (INIS)
Araripe, Denise R.; Vasconcelos, Marina B.A.
2005-01-01
The goal of the present work was to characterize soil samples and sediment of mangrove belong the Itingussu river drainage basin, with a view to investigate the lithological signature of it. This small drainage ends in area not yet largely impacted by other sources such as industrial and domestic waste in relation to the elements studied here. The results showed some enrichment of the U,Th and some light rare earth elements in the Itingussu sediment sample. This represent the leucocratic rock signature, according to the normalized of data by upper crustal mean values . (author)
Lam, Wai Sze Tiffany
Optical components made of anisotropic materials, such as crystal polarizers and crystal waveplates, are widely used in many complex optical system, such as display systems, microlithography, biomedical imaging and many other optical systems, and induce more complex aberrations than optical components made of isotropic materials. The goal of this dissertation is to accurately simulate the performance of optical systems with anisotropic materials using polarization ray trace. This work extends the polarization ray tracing calculus to incorporate ray tracing through anisotropic materials, including uniaxial, biaxial and optically active materials. The 3D polarization ray tracing calculus is an invaluable tool for analyzing polarization properties of an optical system. The 3x3 polarization ray tracing P matrix developed for anisotropic ray trace assists tracking the 3D polarization transformations along a ray path with series of surfaces in an optical system. To better represent the anisotropic light-matter interactions, the definition of the P matrix is generalized to incorporate not only the polarization change at a refraction/reflection interface, but also the induced optical phase accumulation as light propagates through the anisotropic medium. This enables realistic modeling of crystalline polarization elements, such as crystal waveplates and crystal polarizers. The wavefront and polarization aberrations of these anisotropic components are more complex than those of isotropic optical components and can be evaluated from the resultant P matrix for each eigen-wavefront as well as for the overall image. One incident ray refracting or reflecting into an anisotropic medium produces two eigenpolarizations or eigenmodes propagating in different directions. The associated ray parameters of these modes necessary for the anisotropic ray trace are described in Chapter 2. The algorithms to calculate the P matrix from these ray parameters are described in Chapter 3 for
International Nuclear Information System (INIS)
Leclerc, J.P.
2001-01-01
The first international congress on 'Tracers and tracing methods' took place in Nancy in May 2001. The objective of this second congress was to present the current status and trends on tracing methods and their applications. It has given the opportunity to people from different fields to exchange scientific information and knowledge about tracer methodologies and applications. The target participants were the researchers, engineers and technologists of various industrial and research sectors: chemical engineering, environment, food engineering, bio-engineering, geology, hydrology, civil engineering, iron and steel production... Two sessions have been planned to cover both fundamental and industrial aspects: 1)fundamental development (tomography, tracer camera visualization and particles tracking; validation of computational fluid dynamics simulations by tracer experiments and numerical residence time distribution; new tracers and detectors or improvement and development of existing tracing methods; data treatments and modeling; reactive tracer experiments and interpretation) 2)industrial applications (geology, hydrogeology and oil field applications; civil engineering, mineral engineering and metallurgy applications; chemical engineering; environment; food engineering and bio-engineering). The program included 5 plenary lectures, 23 oral communications and around 50 posters. Only 9 presentations are interested for the INIS database
Group sparse canonical correlation analysis for genomic data integration.
Lin, Dongdong; Zhang, Jigang; Li, Jingyao; Calhoun, Vince D; Deng, Hong-Wen; Wang, Yu-Ping
2013-08-12
The emergence of high-throughput genomic datasets from different sources and platforms (e.g., gene expression, single nucleotide polymorphisms (SNP), and copy number variation (CNV)) has greatly enhanced our understandings of the interplay of these genomic factors as well as their influences on the complex diseases. It is challenging to explore the relationship between these different types of genomic data sets. In this paper, we focus on a multivariate statistical method, canonical correlation analysis (CCA) method for this problem. Conventional CCA method does not work effectively if the number of data samples is significantly less than that of biomarkers, which is a typical case for genomic data (e.g., SNPs). Sparse CCA (sCCA) methods were introduced to overcome such difficulty, mostly using penalizations with l-1 norm (CCA-l1) or the combination of l-1and l-2 norm (CCA-elastic net). However, they overlook the structural or group effect within genomic data in the analysis, which often exist and are important (e.g., SNPs spanning a gene interact and work together as a group). We propose a new group sparse CCA method (CCA-sparse group) along with an effective numerical algorithm to study the mutual relationship between two different types of genomic data (i.e., SNP and gene expression). We then extend the model to a more general formulation that can include the existing sCCA models. We apply the model to feature/variable selection from two data sets and compare our group sparse CCA method with existing sCCA methods on both simulation and two real datasets (human gliomas data and NCI60 data). We use a graphical representation of the samples with a pair of canonical variates to demonstrate the discriminating characteristic of the selected features. Pathway analysis is further performed for biological interpretation of those features. The CCA-sparse group method incorporates group effects of features into the correlation analysis while performs individual feature
‘Canonization in early twentieth-century Chinese art history’
Directory of Open Access Journals (Sweden)
Guo Hui
2014-06-01
Full Text Available Since the 1980s, the discussion of canons has been a dominant theme in the discipline of Western art history. Various concerns have emerged regarding ‘questions of artistic judgment’, ‘the history genesis of masterpieces’, ‘variations in taste’, ‘the social instruments of canonicity’, and ‘how canons disappear’. Western art historians have considered how the canon’s appearance in Western visual art embodies aesthetic, ideological, cultural, social, and symbolic values. In Chinese art history, the idea of a canon including masterpieces, important artists, and forms of art, dates back to the mid ninth century when Zhang Yanyuan wrote his painting history Record of Famous Painters of All the Dynasties. Faced with quite different political, economic, and social conditions amid the instability of the early twentieth century, Chinese scholars attempted to discover new canons for cultural orthodoxy and authority. Modern means for canonization, such as museums and exhibition displays, cultural and academic institutions, and massive art publications with image reproduction in good quality, brought the process up to an unprecedented speed. It is true that most of these means have comparable counterparts in pre-modern times. However, their enormous scope and overwhelming influence are far beyond the reach of their imperial counterparts. Through an inter-textual reading of the publications on Chinese art history in early twentieth-century China, this paper explores the transformation of canons in order to shed light on why and how canonical formation happened during the Republican period of China. Despite the diverse styles and strategies which Chinese writers used in their narratives, Chinese art historical books produced during the Republican period canonized and de-canonized artworks. In this paper, the discussion of these texts, with reference to other art historical works, comprises three parts: 1 canon formation of artistic forms
Inhibition of canonical WNT signaling attenuates human leiomyoma cell growth
Ono, Masanori; Yin, Ping; Navarro, Antonia; Moravek, Molly B.; Coon, John S.; Druschitz, Stacy A.; Gottardi, Cara J.; Bulun, Serdar E.
2014-01-01
Objective Dysregulation of WNT signaling plays a central role in tumor cell growth and progression. Our goal was to assess the effect of three WNT/β-catenin pathway inhibitors, Inhibitor of β-Catenin And TCF4 (ICAT), niclosamide, and XAV939 on the proliferation of primary cultures of human uterine leiomyoma cells. Design Prospective study of human leiomyoma cells obtained from myomectomy or hysterectomy. Setting University research laboratory. Patient(s) Women (n=38) aged 27–53 years undergoing surgery. Intervention(s) Adenoviral ICAT overexpression or treatment with varying concentrations of niclosamide or XAV939. Main Outcome Measure(s) Cell proliferation, cell death, WNT/β-catenin target gene expression or reporter gene regulation, β-catenin levels and cellular localization. Result(s) ICAT, niclosamide, or XAV939 inhibit WNT/β-catenin pathway activation and exert anti-proliferative effects in primary cultures of human leiomyoma cells. Conclusion(s) Three WNT/β-catenin pathway inhibitors specifically block human leiomyoma growth and proliferation, suggesting that the canonical WNT pathway may be a potential therapeutic target for the treatment of uterine leiomyoma. Our findings provide rationale for further preclinical and clinical evaluation of ICAT, niclosamide, and XAV939 as candidate anti-tumor agents for uterine leiomyoma. PMID:24534281
Canon multifunction copier machines – now with onsite support!
2013-01-01
Following a retendering process in 2012, the IT Department is pleased to announce that leased multifunction copier machines are now covered by onsite support, provided by Canon technicians via the CERN Service Desk support system. You can now contact the Service Desk regarding any problems or requests for toner: Telephone: 77777 Email: Service-Desk@cern.ch Please remember to quote the machine printer name and/or serial number (marked on the side of the machine). The following submission forms are available online: Report a failure with a printer or copier Request for network printer or copier installation or move Request toner/ink for my printer or copier The website below details the range of models available, all of which include print, photocopy and scan-to-mail functions as standard. These multifunction copier machines are leased subject to a monthly charge (minimum of 48 months) plus a “per click” charge to cover consumables (except staples), leaving you noth...
Canonical autophagy does not contribute to cellular radioresistance
International Nuclear Information System (INIS)
Schaaf, Marco B.E.; Jutten, Barry; Keulers, Tom G.; Savelkouls, Kim G.M.; Peeters, Hanneke J.M.; Beucken, Twan van den; Schooten, Frederik-Jan van; Godschalk, Roger W.; Vooijs, Marc; Rouschop, Kasper M.A.
2015-01-01
Background: (Pre)clinical studies indicate that autophagy inhibition increases response to anti-cancer therapies. Although promising, due to contradicting reports, it remains unclear if radiation therapy changes autophagy activity and if autophagy inhibition changes the cellular intrinsic radiosensitivity. Discrepancies may result from different assays and models through off-target effects and influencing other signaling routes. In this study, we directly compared the effects of genetic and pharmacological inhibition of autophagy after irradiation in human cancer cell lines. Materials and methods: Changes in autophagy activity after ionizing radiation (IR) were assessed by flux analysis in eight cell lines. Clonogenic survival, DNA damage (COMET-assay) and H2AX phosphorylation were assessed after chloroquine or 3-methyladenine pretreatment and after ATG7 or LC3b knockdown. Results: IR failed to induce autophagy and chloroquine failed to change intrinsic radiosensitivity of cells. Interestingly, 3-methyladenine and ATG7- or LC3b-deficiency sensitized cancer cells to irradiation. Surprisingly, the radiosensitizing effect of 3-methyladenine was also observed in ATG7 and LC3b deficient cells and was associated with attenuated γ-H2AX formation and DNA damage repair. Conclusion: Our data demonstrate that the anti-tumor effects of chloroquine are independent of changes in intrinsic radioresistance. Furthermore, ATG7 and LC3b support radioresistance independent of canonical autophagy that involves lysosomal degradation
Decoding the auditory brain with canonical component analysis.
de Cheveigné, Alain; Wong, Daniel D E; Di Liberto, Giovanni M; Hjortkjær, Jens; Slaney, Malcolm; Lalor, Edmund
2018-05-15
The relation between a stimulus and the evoked brain response can shed light on perceptual processes within the brain. Signals derived from this relation can also be harnessed to control external devices for Brain Computer Interface (BCI) applications. While the classic event-related potential (ERP) is appropriate for isolated stimuli, more sophisticated "decoding" strategies are needed to address continuous stimuli such as speech, music or environmental sounds. Here we describe an approach based on Canonical Correlation Analysis (CCA) that finds the optimal transform to apply to both the stimulus and the response to reveal correlations between the two. Compared to prior methods based on forward or backward models for stimulus-response mapping, CCA finds significantly higher correlation scores, thus providing increased sensitivity to relatively small effects, and supports classifier schemes that yield higher classification scores. CCA strips the brain response of variance unrelated to the stimulus, and the stimulus representation of variance that does not affect the response, and thus improves observations of the relation between stimulus and response. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.
Applications of temporal kernel canonical correlation analysis in adherence studies.
John, Majnu; Lencz, Todd; Ferbinteanu, Janina; Gallego, Juan A; Robinson, Delbert G
2017-10-01
Adherence to medication is often measured as a continuous outcome but analyzed as a dichotomous outcome due to lack of appropriate tools. In this paper, we illustrate the use of the temporal kernel canonical correlation analysis (tkCCA) as a method to analyze adherence measurements and symptom levels on a continuous scale. The tkCCA is a novel method developed for studying the relationship between neural signals and hemodynamic response detected by functional MRI during spontaneous activity. Although the tkCCA is a powerful tool, it has not been utilized outside the application that it was originally developed for. In this paper, we simulate time series of symptoms and adherence levels for patients with a hypothetical brain disorder and show how the tkCCA can be used to understand the relationship between them. We also examine, via simulations, the behavior of the tkCCA under various missing value mechanisms and imputation methods. Finally, we apply the tkCCA to a real data example of psychotic symptoms and adherence levels obtained from a study based on subjects with a first episode of schizophrenia, schizophreniform or schizoaffective disorder.
Symmetry groups of state vectors in canonical quantum gravity
International Nuclear Information System (INIS)
Witt, D.M.
1986-01-01
In canonical quantum gravity, the diffeomorphisms of an asymptotically flat hypersurface S, not connected to the identity, but trivial at infinity, can act nontrivially on the quantum state space. Because state vectors are invariant under diffeomorphisms that are connected to the identity, the group of inequivalent diffeomorphisms is a symmetry group of states associated with S. This group is the zeroth homotopy group of the group of diffeomorphisms fixing a frame of infinity on S. It is calculated for all hypersurfaces of the form S = S 3 /G-point, where the removed point is thought of as infinity on S and the symmetry group S is the zeroth homotopy group of the group of diffeomorphisms of S 3 /G fixing a point and frame, denoted π 0 Diff/sub F/(S 3 /G). Before calculating π 0 Diff/sub F/ (S 3 /G), it is necessary to find π 0 of the group of diffeomorphisms. Once π 0 Diff(S 3 /G) is known, π 0 Diff/sub x/ 0 (S 3 /G) is calculated using a fiber bundle involving Diff(S 3 /G), Diff/sub x/ 0 (S 3 /G), and S 3 /G. Finally, a fiber bundle involving Diff/sub F/(S 3 /G), Diff(S 3 /G), and the bundle of frames over S 3 /G is used along with π 0 Diff/sub x/ 0 (S 3 /G) to calculate π 0 Diff/sub F/(S 3 /G)
Schwinger–Keldysh canonical formalism for electronic Raman scattering
Energy Technology Data Exchange (ETDEWEB)
Su, Yuehua, E-mail: suyh@ytu.edu.cn
2016-03-01
Inelastic low-energy Raman and high-energy X-ray scatterings have made great progress in instrumentation to investigate the strong electronic correlations in matter. However, theoretical study of the relevant scattering spectrum is still a challenge. In this paper, we present a Schwinger–Keldysh canonical perturbation formalism for the electronic Raman scattering, where all the resonant, non-resonant and mixed responses are considered uniformly. We show how to use this formalism to evaluate the cross section of the electronic Raman scattering off an one-band superconductor. All the two-photon scattering processes from electrons, the non-resonant charge density response, the elastic Rayleigh scattering, the fluorescence, the intrinsic energy-shift Raman scattering and the mixed response, are included. In the mean-field superconducting state, Cooper pairs contribute only to the non-resonant response. All the other responses are dominated by the single-particle excitations and are strongly suppressed due to the opening of the superconducting gap. Our formalism for the electronic Raman scattering can be easily extended to study the high-energy resonant inelastic X-ray scattering.
An optimization approach for fitting canonical tensor decompositions.
Energy Technology Data Exchange (ETDEWEB)
Dunlavy, Daniel M. (Sandia National Laboratories, Albuquerque, NM); Acar, Evrim; Kolda, Tamara Gibson
2009-02-01
Tensor decompositions are higher-order analogues of matrix decompositions and have proven to be powerful tools for data analysis. In particular, we are interested in the canonical tensor decomposition, otherwise known as the CANDECOMP/PARAFAC decomposition (CPD), which expresses a tensor as the sum of component rank-one tensors and is used in a multitude of applications such as chemometrics, signal processing, neuroscience, and web analysis. The task of computing the CPD, however, can be difficult. The typical approach is based on alternating least squares (ALS) optimization, which can be remarkably fast but is not very accurate. Previously, nonlinear least squares (NLS) methods have also been recommended; existing NLS methods are accurate but slow. In this paper, we propose the use of gradient-based optimization methods. We discuss the mathematical calculation of the derivatives and further show that they can be computed efficiently, at the same cost as one iteration of ALS. Computational experiments demonstrate that the gradient-based optimization methods are much more accurate than ALS and orders of magnitude faster than NLS.
Canonical quantization of the Proca field in the Rindler wedge
International Nuclear Information System (INIS)
Castineiras, Jorge; Correa, Emerson Benedito Sousa; Crispino, Luis Carlos Bassalo; Matsas, George Emanuel Avraam
2009-01-01
Full text. We perform the canonical quantization of a massive vector field in Rindler spacetime. We pay special attention to the zero frequency modes of the Proca field because these are the modes that interact with structureless sources which are static in the Rindler spacetime. Our motivation is the computation of the total response of a static source with some fixed proper acceleration a 0 in Rindler spacetime interacting with the zero energy massive vector particle of the Fulling-Davies-Unruh (FDU) thermal bath and compare it with the response of a static source with the same proper acceleration a 0 outside a Schwarzschild black hole interacting with the massive vector particles of the Hawking thermal radiation. Surprisingly, as it was already shown in a resent article, these responses would be identical if a massless scalar field is consider instead of the massive vector field, the field outside the Schwarzschild black hole is supposed to be in the Unruh vacuum and the source proper acceleration is the same in both cases. This came as a surprise because structureless static sources can only interact with zero-frequency field modes. Such modes can probe the global geometry of spacetime and are accordingly quite different in Schwarzschild spacetime and in the Rindler wedge. (author)
On the Syntax of Canonical Comparatives in European Portuguese
Directory of Open Access Journals (Sweden)
Gabriela Matos
2002-06-01
Full Text Available Comparative constructions in English and other Germanic and Romance languages have been analysed either as subordinate or coordinate structures. Focussing European Portuguese (=EP we will argue, from a syntactic point of view, that there is evidence for the coordinate nature of canonical comparatives in this language. In fact, not only many properties of these constructions distinguish them from subordinate structures, but also most of the characteristics attributed to the subordinate status of comparatives can also be accounted for within the coordinate approach. In particular, the selection of the comparative phrase by the degree marker in the first term of comparison may be viewed as a case of correlative coordination. In the same line of reasoning, the islands effects exhibited by comparative clauses do not constitute a compelling evidence for the systematic presence of a wh-operator, since they may also arise in other cases of A-bar movement. So, though accepting that Comparative and Subcomparative deletions are two distinct cases of Operator-variable chain, relying on empirical evidence across other Romance languages, we will analyse Comparative Deletion in European Portuguese as an instance of (Quantified Null Object and we will impute Subcomparative deletion to Quantifier Raising at LF for scope assignment purposes.
A Laboratory Astrophysical Jet to Study Canonical Flux Tubes
Energy Technology Data Exchange (ETDEWEB)
You, Setthivoine [Univ. of Washington, Seattle, WA (United States)
2017-12-20
Understanding the interaction between plasma flows and magnetic fields remains a fundamental problem in plasma physics, with important applications to astrophysics, fusion energy, and advanced space propulsion. For example, flows are of primary importance in astrophysical jets even if it is not fully understood how jets become so long without becoming unstable. Theories for the origin of magnetic fields in the cosmos rely on flowing charged fluids that should generate magnetic fields, yet this remains to be demonstrated experimentally. Fusion energy reactors can be made smaller with flows that improve stability and confinement. Advanced space propulsion could be more efficient with collimated and stable plasma flows through magnetic nozzles but must eventually detach from the nozzle. In all these cases, there appears to be a spontaneous emergence of flowing and/or magnetic structures, suggesting a form of self-organization in plasmas. Beyond satisfying simple intellectual curiosity, understanding plasma self-organization could enable the development of methods to control plasma structures for fusion energy, space propulsion, and other applications. The research project has therefore built a theory and an experiment to investigate the interaction between magnetic fields and plasma flows. The theory is called canonical field theory for short, and the experiment is called Mochi after a rice cake filled with surprising, yet delicious fillings.
Cosmological implications of grand unified theories
International Nuclear Information System (INIS)
Nanopoulos, D.V.
1982-01-01
These lectures, mainly devoted to the cosmological implications of GUTs, also include the essential ingredients of GUTs and some of their important applications to particle physics. Section 1 contains some basic points concerning the structure of the standard strong and electroweak interactions prior to grand unification. A detailed expose of GUTs is attempted in sect. 2, including their basci principles and their consequences for particle physics. The minimal, simplest GUT, SU 5 is analysed in some detail and it will be used throughout these lectures as the GUT prototype. Finally, sect. 3 contains the most important cosmological implications of GUTs, including baryon number generation in the early Universe (in rather lengthy detail), dissipative processes in the very early Universe, grand unified monopoles, etc. (orig./HSI)
International Nuclear Information System (INIS)
Huber, M.; Staeuble, J.
1987-01-01
Nagra has identified four potential sites for a repository for low- and intermediate-level waste. Exploration work is already underway at Oberbauenstock (UR) and Piz Pian Grand (GR). As part of the investigations in the Piz Pian Grand area, geological surface mapping was carried out between 1984 and 1987. Since the data obtained is still being evaluated, it would be premature to draw any interpretative conclusions at this stage. On the other hand, some of the most significant observations of this work can be summarised here. As a first step, the geological framework in which these investigations are to be seen should be defined. Observations will then be made on the rock content (lithology) and geometric structure (structural geology) of the area. (author) 6 figs
Place Of Canon Law Of The Russian Empire In The System Io Humanitarian
Directory of Open Access Journals (Sweden)
Alexandra A. Dorskaya
2014-12-01
Full Text Available In the present article author examines place of canon law in the system of humanitarian sciences in the Russian Empire at the end of XVIII - early XX centuries. Author reveals interaction of canon law with philosophy, philology, jurisprudence. In particular, author shows influence of various philosophical schools on the development of the canon law science, value of foreign researches translation for the development of national science of canon law starting from the end of the XVIII century. It is found that all researchers in the field of canon law had special scientific works on philosophy. Interference of cannon law and theological science – dogmatic theology, moral theology, liturgy, church geography, chronology, statistics, history, archeology, pastoral theology is considered. In the article works of leading specialists in the field of canon law the second half of XIX - early XX centuries that were left as a significant legacy after the Archimandrite Gabriel, I.S. Berdnikova, N.A. Zaozerskii, I.M. Skvortsov and others are analyzed. In conclusion author shows complexity and urgency of the problem in the process of church (canon law study at the present stage, when there is some struggle between the secular and religious science.
Base pair probability estimates improve the prediction accuracy of RNA non-canonical base pairs.
Directory of Open Access Journals (Sweden)
Michael F Sloma
2017-11-01
Full Text Available Prediction of RNA tertiary structure from sequence is an important problem, but generating accurate structure models for even short sequences remains difficult. Predictions of RNA tertiary structure tend to be least accurate in loop regions, where non-canonical pairs are important for determining the details of structure. Non-canonical pairs can be predicted using a knowledge-based model of structure that scores nucleotide cyclic motifs, or NCMs. In this work, a partition function algorithm is introduced that allows the estimation of base pairing probabilities for both canonical and non-canonical interactions. Pairs that are predicted to be probable are more likely to be found in the true structure than pairs of lower probability. Pair probability estimates can be further improved by predicting the structure conserved across multiple homologous sequences using the TurboFold algorithm. These pairing probabilities, used in concert with prior knowledge of the canonical secondary structure, allow accurate inference of non-canonical pairs, an important step towards accurate prediction of the full tertiary structure. Software to predict non-canonical base pairs and pairing probabilities is now provided as part of the RNAstructure software package.
Base pair probability estimates improve the prediction accuracy of RNA non-canonical base pairs.
Sloma, Michael F; Mathews, David H
2017-11-01
Prediction of RNA tertiary structure from sequence is an important problem, but generating accurate structure models for even short sequences remains difficult. Predictions of RNA tertiary structure tend to be least accurate in loop regions, where non-canonical pairs are important for determining the details of structure. Non-canonical pairs can be predicted using a knowledge-based model of structure that scores nucleotide cyclic motifs, or NCMs. In this work, a partition function algorithm is introduced that allows the estimation of base pairing probabilities for both canonical and non-canonical interactions. Pairs that are predicted to be probable are more likely to be found in the true structure than pairs of lower probability. Pair probability estimates can be further improved by predicting the structure conserved across multiple homologous sequences using the TurboFold algorithm. These pairing probabilities, used in concert with prior knowledge of the canonical secondary structure, allow accurate inference of non-canonical pairs, an important step towards accurate prediction of the full tertiary structure. Software to predict non-canonical base pairs and pairing probabilities is now provided as part of the RNAstructure software package.
Grand Gulf-prioritization of regulatory requirements
International Nuclear Information System (INIS)
Meisner, M.J.
1993-01-01
As cost pressures mount, Grand Gulf nuclear station (GGNS) is relying increasingly on various prioritization approaches to implement, modify, eliminate, or defer regulatory requirements. Regulatory requirements can be prioritized through the use of three measures: (1) safety (or risk) significance; (2) cost; and (3) public policy (or political) significance. This paper summarizes GGNS' efforts to implement solutions to regulatory issues using these three prioritization schemes to preserve a balance between cost and safety benefit
Between two evils: Investors prefer grand corruption!
Graf Lambsdorff, Johann
2005-01-01
Recent empirical studies claim that, in addition to levels of corruption, investors are deterred by its unpredictability. I claim instead that it is petty corruption that deters investors. I employ seven subcomponents of corruption for a sample of 102 countries that appear in the 2003 Global Competitiveness Report of the WEF. The second principal component of this data depicts a grand, political type, embracing corruption in government policymaking and in judicial decisions as opposed to corr...
Grand Challenges in Music Information Research
Goto, Masataka
2012-01-01
This paper discusses some grand challenges in which music information research will impact our daily lives and our society in the future. Here, some fundamental questions are how to provide the best music for each person, how to predict music trends, how to enrich human-music relationships, how to evolve new music, and how to address environmental, energy issues by using music technologies. Our goal is to increase both attractiveness and social impacts of music information research in the fut...
Meliponiculture in Rio Grande do Norte
Directory of Open Access Journals (Sweden)
Ulysses Madureira Maia
2015-12-01
Full Text Available ABSTRACT. Maia U.M., Jaffe R., Carvalho A.T. & Imperatriz-Fonseca V.L. [Meliponiculture in Rio Grande do Norte.] Meliponicultura no Rio Grande do Norte. Revista Brasileira de Medicina Veterinária, 37(4:327-333, 2015. Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Avenida Bandeirantes, 3900, Monte Alegre, Ribeirão Preto, SP 14040-901, Brasil. E-mail: ummaia@usp.br This study aimed to assess the current status of stingless bee beekeeping (meliponiculture in the State of Rio Grande do Norte, Brazil, with the aid of structured questionnaires made during visits to beekeepers. The results were compared with a previous census made in the state and with a similar study from Australia. Meliponiculture in Rio Grande do Norte is still informal and little standardized. The activity has grown in recent years considering the mean number of nests per beekeeper. Most apiaries are formed of up to 50 colonies, usually distributed in the backyards of homes. Twelve species of stingless bees were reared in the state, and the most common was the “Jandaíra” bee (Melipona subnitida, whose honey is considered medicinal. While many beekeepers already know the importance of bees as pollinators, stingless bees are still not used for crop pollination. Compared to a recent analysis of beekeeping in Australia, meliponiculture in Brazil is more traditional, honey is the main product and the number of colonies per beekeeper is much higher. Our results highlight the need to reinforce knowledge about bees and promote specific training aimed at improving and standardizing management practices.
Neutrino mixing in a grand unified theory
International Nuclear Information System (INIS)
Milton, K.; Tanaka, K.
1980-01-01
Neutrino mixing in a grand unified theory in which the neutrino mass matrix is determined by the Gell-Mann-Ramond-Slansky mechanism was investigated. With an arbitrary real right-handed Majorana mass matrix which incorporates three neutrino mass scales, the effects of the up-quark mass matrix are found to be dominant and as a result no significant mixing of ν/sub e/ occurs, while ν/sub μ/ - ν/sub γ/ mixing can be substantial
The Grand Strategy of Charles de Gaulle
1989-09-08
4. TITLE AND SUBTITLE The Grand Startegy of Charles de Gaulle 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S...dependent on French influence within NATO and the Common Market . De Gaulle frequently used these fora to veto British and American initiatives. As Cook...the reserve currency. Gold would be the basis of international finance and a French-dominated European Common Market would provide the framework
Linac particle tracing simulations
International Nuclear Information System (INIS)
Lysenko, W.P.
1979-01-01
A particle tracing code was developed to study space--charge effects in proton or heavy-ion linear accelerators. The purpose is to study space--charge phenomena as directly as possible without the complications of many accelerator details. Thus, the accelerator is represented simply by harmonic oscillator or impulse restoring forces. Variable parameters as well as mismatched phase--space distributions were studied. This study represents the initial search for those features of the accelerator or of the phase--space distribution that lead to emittance growth
Osteoporosis and trace elements
DEFF Research Database (Denmark)
Aaseth, J.; Boivin, G.; Andersen, Ole
2012-01-01
More than 200 million people are affected by osteoporosis worldwide, as estimated by 2 million annual hip fractures and other debilitating bone fractures (vertebrae compression and Colles' fractures). Osteoporosis is a multi-factorial disease with potential contributions from genetic, endocrine...... in new bone and results in a net gain in bone mass, but may be associated with a tissue of poor quality. Aluminum induces impairment of bone formation. Gallium and cadmium suppresses bone turnover. However, exact involvements of the trace elements in osteoporosis have not yet been fully clarified...
[Grand Banks activity : updates and opportunities
International Nuclear Information System (INIS)
Bruce, G.
1998-01-01
An overview of the exploration and on-going activities by the petroleum industry on the Grand Banks of Newfoundland was presented. The two offshore oil developments underway are Hibernia and Terra Nova, both located in the Jeanne d'Arc Basin. Current production from Hibernia is 68,000 bopd, expected to rise to 130,000 bopd in 1999. The Terra Nova Field is still under development. Total recoverable reserves from the 17 discoveries made in the Jeanne d'Arc Basin are estimated at 1.6 billion barrels of oil and 4 trillion cubic feet of gas. Industry participants in the area include Amoco, Petro-Canada, Mobil, Chevron, Husky and Norsk Hydro. Petro-Canada believes the Grand Banks represent one of the best opportunities for oil anywhere in the world. There are currently 21 exploration licenses held on the Grand Banks. Major attractions of the area include the large reserve potential, the relatively low finding costs, the size of the pools being discovered, improvements in offshore technology that have substantially lowered development costs, and a profit-sensitive generic royalty regime that ensures reasonable rates of return for investors. figs
Proton decay in grand unified theories
International Nuclear Information System (INIS)
Lucha, W.
1984-01-01
Interactions which violate the conservation of baryon and lepton number represent an intrinsic part of all grand unified theories (GUTs) of strong and electroweak interactions. These new interactions - predicted within the framework of GUTs - generate B and L violating four-fermion interactions via the exchange of superheavy particles which cannot be ascribed a well-defined baryon or lepton number. The effective coupling constant of these four-fermion interactions might be large enough to make the proton decay detectable by the present generation of experiments. In this review the basic concepts of conventional as well as supersymmetric GUTs relevant for proton decay are sketched. The baryon number violating sector of grand unified theories is discussed in more detail. Special emphasis is laid on the various selection rules arising as consequences of low-energy gauge invariance and supersymmetry for proton decay. These selection rules already determine the coarse pattern of the resulting decay modes and branching ratios without any reference to or detailed knowledge of the underlying grand unified theory. Finally the numerous theoretical predictions are summarized and confronted with experiment. (Author)
Raptor Use of the Rio Grande Gorge
Energy Technology Data Exchange (ETDEWEB)
Ponton, David A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2015-03-20
The Rio Grande Gorge is a 115 km long river canyon located in Southern Colorado (15 km) and Northern New Mexico (100 km). The majority of the canyon is under the administration of the Bureau of Land Management {BLM), and 77 km of the canyon south of the Colorado/New Mexico border are designated Wild River under the National Wild and Scenic Rivers Act of 1968. Visits I have made to the Rio Grande Gorge over the past 15 .years disclosed some raptor utilization. As the Snake River Birds of Prey Natural Area gained publicity, its similarity to the Rio Grande Gorge became obvious, and I was intrigued by the possibility of a high raptor nesting density in the Gorge. A survey in 1979 of 20 km of the northern end of the canyon revealed a moderately high density of red-tailed hawks and prairie falcons. With the encouragement of that partial survey, and a need to assess the impact of river-running on nesting birds of prey, I made a more comprehensive survey in 1980. The results of my surveys, along with those of a 1978 helicopter survey by the BLM, are presented in this report, as well as general characterization of the area, winter use by raptors, and an assessment of factors influencing the raptor population.
Methods of Weyl representation of the phase space and canonical transformations. 1
International Nuclear Information System (INIS)
Budanov, V.G.
1984-01-01
The kernel structure of canonical transformation and differential equation for the intertwining operator is found. The Weyl symbol of operators producing linear canonical transformations is associated with the Cayley transformation of classical canonical transformation. Due to the invariance of the Weyl formalism a complete study of singularity and factorization of these symbols is manageable. In particular, one can study the symbols of Green functions and elements of Lie groups and find the spectra of arbitrary stationary quadratic Hamiltonians with the help of the known classification of the spectra of classical systems
Linear response calculation using the canonical-basis TDHFB with a schematic pairing functional
International Nuclear Information System (INIS)
Ebata, Shuichiro; Nakatsukasa, Takashi; Yabana, Kazuhiro
2011-01-01
A canonical-basis formulation of the time-dependent Hartree-Fock-Bogoliubov (TDHFB) theory is obtained with an approximation that the pair potential is assumed to be diagonal in the time-dependent canonical basis. The canonical-basis formulation significantly reduces the computational cost. We apply the method to linear-response calculations for even-even nuclei. E1 strength distributions for proton-rich Mg isotopes are systematically calculated. The calculation suggests strong Landau damping of giant dipole resonance for drip-line nuclei.
The canonical partial metric and the uniform convexity on normed spaces
Directory of Open Access Journals (Sweden)
S. Oltra
2005-10-01
Full Text Available In this paper we introduce the notion of canonical partial metric associated to a norm to study geometric properties of normed spaces. In particular, we characterize strict convexity and uniform convexity of normed spaces in terms of the canonical partial metric defined by its norm. We prove that these geometric properties can be considered, in this sense, as topological properties that appear when we compare the natural metric topology of the space with the non translation invariant topology induced by the canonical partial metric in the normed space.
An evaluation of canonical forms for non-rigid 3D shape retrieval
Pickup, David; Liu, Juncheng; Sun, Xianfang; Rosin, Paul L.; Martin, Ralph R.; Cheng, Zhiquan; Lian, Zhouhui; Nie, Sipin; Jin, Longcun; Shamai, Gil; Sahillioğlu, Yusuf; Kavan, Ladislav
2018-01-01
Canonical forms attempt to factor out a non-rigid shape’s pose, giving a pose-neutral shape. This opens up the\\ud possibility of using methods originally designed for rigid shape retrieval for the task of non-rigid shape retrieval.\\ud We extend our recent benchmark for testing canonical form algorithms. Our new benchmark is used to evaluate a\\ud greater number of state-of-the-art canonical forms, on five recent non-rigid retrieval datasets, within two different\\ud retrieval frameworks. A tota...
Algorithmic transformation of multi-loop master integrals to a canonical basis with CANONICA
Meyer, Christoph
2018-01-01
The integration of differential equations of Feynman integrals can be greatly facilitated by using a canonical basis. This paper presents the Mathematica package CANONICA, which implements a recently developed algorithm to automatize the transformation to a canonical basis. This represents the first publicly available implementation suitable for differential equations depending on multiple scales. In addition to the presentation of the package, this paper extends the description of some aspects of the algorithm, including a proof of the uniqueness of canonical forms up to constant transformations.
An unconventional canonical quantization of local scalar fields over quantum space-time
International Nuclear Information System (INIS)
Banai, M.
1985-12-01
An unconventional extension of the canonical quantization method is presented for a classical local field theory. The proposed canonical commutation relations have a solution in the A-valued Hilbert space where A is the algebra of the bounded operators of the Hilbert space Lsup(2) (IRsup(3)). The canonical equations as operator equations are equivalent formally with the classical field equations, and are well defined for interacting systems, too. This model of quantized field lacks some of the difficulties of the conventional approach. Examples satisfying the asymptotic condition provide examples for Haag-Kastler's axioms, however, they satisfy Wightman's axioms only partially. (author)