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Sample records for two-matrix hypergeometric function

  1. Elliptic hypergeometric functions and the representation theory

    International Nuclear Information System (INIS)

    Spiridonov, V.P.

    2011-01-01

    Full text: (author)Elliptic hypergeometric functions were discovered around ten years ago. They represent the top level known generalization of the Euler beta integral and Euler-Gauss 2 F 1 hypergeometric function. In general form they are defined by contour integrals involving elliptic gamma functions. We outline the structure of the simplest examples of such functions and discuss their relations to the representation theory of the classical Lie groups and their various deformations. In one of the constructions elliptic hypergeometric integrals describe purely group-theoretical objects having the physical meaning of superconformal indices of four-dimensional supersymmetric gauge field theories

  2. Elliptic hypergeometric functions associated with root systems

    OpenAIRE

    Rosengren, Hjalmar; Warnaar, S. Ole

    2017-01-01

    We give a survey of elliptic hypergeometric functions associated with root systems, comprised of three main parts. The first two form in essence an annotated table of the main evaluation and transformation formulas for elliptic hypergeometric integeral and series on root systems. The third and final part gives an introduction to Rains' elliptic Macdonald-Koornwinder theory (in part also developed by Coskun and Gustafson).

  3. Hypergeometric Functions with Integral Parameter Differences

    DEFF Research Database (Denmark)

    Karlsson, Per W.

    1971-01-01

    For a generalized hypergeometric function pFq(z) with positive integral differences between certain numerator and denominator parameters, a formula expressing the pFq(z) as a finite sum of lower-order functions is proved. From this formula, Minton's two summation theorems for p = q + 1, z = 1...

  4. RATIONAL APPROXIMATIONS TO GENERALIZED HYPERGEOMETRIC FUNCTIONS.

    Science.gov (United States)

    Under weak restrictions on the various free parameters, general theorems for rational representations of the generalized hypergeometric functions...and certain Meijer G-functions are developed. Upon specialization, these theorems yield a sequency of rational approximations which converge to the

  5. Rigidity of monodromies for Appell's hypergeometric functions

    Directory of Open Access Journals (Sweden)

    Yoshishige Haraoka

    2015-01-01

    Full Text Available For monodromy representations of holonomic systems, the rigidity can be defined. We examine the rigidity of the monodromy representations for Appell's hypergeometric functions, and get the representations explicitly. The results show how the topology of the singular locus and the spectral types of the local monodromies work for the study of the rigidity.

  6. HYPERDIRE. HYPERgeometric functions DIfferential REduction. MATEMATICA based packages for differential reduction of generalized hypergeometric functions. FD and FS Horn-type hypergeometric functions of three variables

    International Nuclear Information System (INIS)

    Bytev, Vladimir V.; Kalmykov, Mikhail Yu.; Moch, Sven-Olaf; Hamburg Univ.

    2013-12-01

    HYPERDIRE is a project devoted to the creation of a set of Mathematica based programs for the differential reduction of hypergeometric functions. The current version includes two parts: the first one, FdFunction, for manipulations with Appell hypergeometric functions F D of r variables; and the second one, FsFunction, for manipulations with Lauricella-Saran hypergeometric functions F S of three variables. Both functions are related with one-loop Feynman diagrams.

  7. CIMPA Summer School on Arithmetic and Geometry Around Hypergeometric Functions

    CERN Document Server

    Uludağ, A; Yoshida, Masaaki; Arithmetic and Geometry Around Hypergeometric Functions

    2007-01-01

    This volume comprises the Lecture Notes of the CIMPA Summer School "Arithmetic and Geometry around Hypergeometric Functions" held at Galatasaray University, Istanbul in 2005. It contains lecture notes, a survey article, research articles, and the results of a problem session. Key topics are moduli spaces of points on P1 and Picard-Terada-Deligne-Mostow theory, moduli spaces of K3 surfaces, complex hyperbolic geometry, ball quotients, GKZ hypergeometric structures, Hilbert and Picard modular surfaces, uniformizations of complex orbifolds, algebraicity of values of Schwartz triangle functions, and Thakur's hypergeometric function. The book provides a background, gives detailed expositions and indicates new research directions. It is directed to postgraduate students and researchers.

  8. Correlation functions of two-matrix models

    International Nuclear Information System (INIS)

    Bonora, L.; Xiong, C.S.

    1993-11-01

    We show how to calculate correlation functions of two matrix models without any approximation technique (except for genus expansion). In particular we do not use any continuum limit technique. This allows us to find many solutions which are invisible to the latter technique. To reach our goal we make full use of the integrable hierarchies and their reductions which were shown in previous papers to naturally appear in multi-matrix models. The second ingredient we use, even though to a lesser extent, are the W-constraints. In fact an explicit solution of the relevant hierarchy, satisfying the W-constraints (string equation), underlies the explicit calculation of the correlation functions. The correlation functions we compute lend themselves to a possible interpretation in terms of topological field theories. (orig.)

  9. Conformal field theory and functions of hypergeometric type

    International Nuclear Information System (INIS)

    Isachenkov, Mikhail

    2016-03-01

    Conformal field theory provides a universal description of various phenomena in natural sciences. Its development, swift and successful, belongs to the major highlights of theoretical physics of the late XX century. In contrast, advances of the theory of hypergeometric functions always assumed a slower pace throughout the centuries of its existence. Functional identities studied by this mathematical discipline are fascinating both in their complexity and beauty. This thesis investigates the interrelation of two subjects through a direct analysis of three CFT problems: two-point functions of the 2d strange metal CFT, three-point functions of primaries of the non-rational Toda CFT and kinematical parts of Mellin amplitudes for scalar four-point functions in general dimensions. We flash out various generalizations of hypergeometric functions as a natural mathematical language for two of these problems. Several new methods inspired by extensions of classical results on hypergeometric functions, are presented.

  10. Conformal field theory and functions of hypergeometric type

    Energy Technology Data Exchange (ETDEWEB)

    Isachenkov, Mikhail

    2016-03-15

    Conformal field theory provides a universal description of various phenomena in natural sciences. Its development, swift and successful, belongs to the major highlights of theoretical physics of the late XX century. In contrast, advances of the theory of hypergeometric functions always assumed a slower pace throughout the centuries of its existence. Functional identities studied by this mathematical discipline are fascinating both in their complexity and beauty. This thesis investigates the interrelation of two subjects through a direct analysis of three CFT problems: two-point functions of the 2d strange metal CFT, three-point functions of primaries of the non-rational Toda CFT and kinematical parts of Mellin amplitudes for scalar four-point functions in general dimensions. We flash out various generalizations of hypergeometric functions as a natural mathematical language for two of these problems. Several new methods inspired by extensions of classical results on hypergeometric functions, are presented.

  11. HYPERDIRE. HYPERgeometric functions DIfferential REduction. MATEMATICA based packages for differential reduction of generalized hypergeometric functions. F{sub D} and F{sub S} Horn-type hypergeometric functions of three variables

    Energy Technology Data Exchange (ETDEWEB)

    Bytev, Vladimir V. [Joint Inst. for Nuclear Research, Dubna (Russian Federation); Kalmykov, Mikhail Yu. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Moch, Sven-Olaf [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik

    2013-12-15

    HYPERDIRE is a project devoted to the creation of a set of Mathematica based programs for the differential reduction of hypergeometric functions. The current version includes two parts: the first one, FdFunction, for manipulations with Appell hypergeometric functions F{sub D} of r variables; and the second one, FsFunction, for manipulations with Lauricella-Saran hypergeometric functions F{sub S} of three variables. Both functions are related with one-loop Feynman diagrams.

  12. Hypergeometric series recurrence relations and some new orthogonal functions

    International Nuclear Information System (INIS)

    Wilson, J.A.

    1978-01-01

    A set of hypergeometric orthogonal polynomials, a set of biorthogonal rational functions generalizing them, and some new three-term relations for hypergeometric series containing properties of these functions are exhibited. The orthogonal polynomials depend on four free parameters, and their orthogonality relations include as special or limiting cases the orthogonalities for the classical polynomials, the Hahn and dual Hahn polynomials, Pollaczek's polynomials orthogonal on an infinite interval, and the 6-j symbols of angular momentum in quantum mechanics. Their properties include a second-order difference equation and a Rodrigues-type formula involving a divided difference operator

  13. Finding new relationships between hypergeometric functions by evaluating Feynman integrals

    Energy Technology Data Exchange (ETDEWEB)

    Kniehl, Bernd A. [Santa Barbara Univ., CA (United States). Kavli Inst. for Theoretical Physics; Tarasov, Oleg V. [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik

    2011-08-15

    Several new relationships between hypergeometric functions are found by comparing results for Feynman integrals calculated using different methods. A new expression for the one-loop propagator-type integral with arbitrary masses and arbitrary powers of propagators is derived in terms of only one Appell hypergeometric function F{sub 1}. From the comparison of this expression with a previously known one, a new relation between the Appell functions F{sub 1} and F{sub 4} is found. By comparing this new expression for the case of equal masses with another known result, a new formula for reducing the F{sub 1} function with particular arguments to the hypergeometric function {sub 3}F{sub 2} is derived. By comparing results for a particular one-loop vertex integral obtained using different methods, a new relationship between F{sub 1} functions corresponding to a quadratic transformation of the arguments is established. Another reduction formula for the F{sub 1} function is found by analysing the imaginary part of the two-loop self-energy integral on the cut. An explicit formula relating the F{sub 1} function and the Gaussian hypergeometric function {sub 2}F{sub 1} whose argument is the ratio of polynomials of degree six is presented. (orig.)

  14. Large parameter cases of the Gauss hypergeometric function

    NARCIS (Netherlands)

    N.M. Temme (Nico)

    2002-01-01

    textabstractWe consider the asymptotic behaviour of the Gauss hypergeometric function when several of the parameters {it a, b, c} are large. We indicate which cases are of interest for orthogonal polynomials (Jacobi, but also Meixner, Krawtchouk, etc.), which results are already available and

  15. HYPERDIRE. HYPERgeometric functions DIfferential REduction. MATHEMATICA based packages for differential reduction of generalized hypergeometric functions pFp-1, F1, F2, F3, F4

    International Nuclear Information System (INIS)

    Bytev, Vladimir V.; Kalmykov, Mikhail Yu.; Kniehl, Bernd A.

    2013-05-01

    HYPERDIRE is a project devoted to the creation of a set of Mathematica based programs for the differential reduction of hypergeometric functions. The current version includes two parts: one, pfq, is relevant for manipulations of hypergeometric functions p+1 F p , and the second one, AppellF1F4, for manipulations with Appell hypergeometric functions F 1 , F 2 , F 3 , F 4 of two variables.

  16. Some results associated with a generalized basic hypergeometric function

    Directory of Open Access Journals (Sweden)

    Rajeev K. Gupta

    2009-05-01

    Full Text Available In this paper, we define a q-extension of the new generalized hypergeometric function given by Saxena et al. in [13], and have investigated the properties of the above new function such as q-differentiation and q-integral representation. The results presented are of general character and the results given earlier by Saxena and Kalla in [14], Virchenko, Kalla and Al-Zamel in [15], Al-Musallam and Kalla in [2, 3], Kobayashi in [7, 8], Saxena et al. in [13], Kumbhat et al. in [11] follow as special cases.

  17. Reduction of Double Clausenian Hypergeometric Functions

    DEFF Research Database (Denmark)

    Karlsson, Per W.

    1996-01-01

    The reduction formulas under consideration are those for which the conditions upon the variables are other than 'fixed values'. Known results are discussed, and some new formulas are derived by series manipulations from various known summation and transformation theorems. The ten functions in thi...

  18. Multivariable hypergeometric functions for ion-atom collisions

    Energy Technology Data Exchange (ETDEWEB)

    Gasaneo, G.; Colavecchia, F.D.; Garibotti, C.R

    1999-06-03

    In this work we present a correlated wave function for a three-body continuum Coulomb problem. This state is described by the two-variables PHI{sub 2} hypergeometric function. We examine the properties of this function and their differences with previous uncorrelated models. The PHI{sub 2} wave function can be considered as a final state of ion-atom ionizing collisions, giving rise to both undistorted (Born-PHI{sub 2}) and distorted (EIS-PHI{sub 2}) models. We obtain double differential cross sections with the Born-PHI{sub 2} theory for proton-helium collisions in the intermediate to high energy regime. They exhibit all the main features of the electronic emission process and agree with the experimental data.

  19. Fractional Integral and Generalized Stieltjes Transforms for Hypergeometric Functions as Transmutation Operators

    NARCIS (Netherlands)

    Koornwinder, T.H.

    2015-01-01

    For each of the eight n-th derivative parameter changing formulas for Gauss hypergeometric functions a corresponding fractional integration formula is given. For both types of formulas the differential or integral operator is intertwining between two actions of the hypergeometric differential

  20. HYPERDIRE HYPERgeometric functions DIfferential REduction. Mathematica-based packages for the differential reduction of generalized hypergeometric functions. Lauricella function FC of three variables

    International Nuclear Information System (INIS)

    Bytev, Vladimir V.; Kniehl, Bernd A.

    2016-12-01

    We present a further extension of the HYPERDIRE project, which is devoted to the creation of a set of Mathematica-based program packages for manipulations with Horn-type hypergeometric functions on the basis of differential equations. Specifically, we present the implementation of the differential reduction for the Lauricella function F C of three variables.

  1. HYPERDIRE HYPERgeometric functions DIfferential REduction. Mathematica-based packages for the differential reduction of generalized hypergeometric functions. Lauricella function F{sub C} of three variables

    Energy Technology Data Exchange (ETDEWEB)

    Bytev, Vladimir V. [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Joint Institute for Nuclear Research, Dubna (Russian Federation); Kniehl, Bernd A. [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik

    2016-12-15

    We present a further extension of the HYPERDIRE project, which is devoted to the creation of a set of Mathematica-based program packages for manipulations with Horn-type hypergeometric functions on the basis of differential equations. Specifically, we present the implementation of the differential reduction for the Lauricella function F{sub C} of three variables.

  2. Generalized hypergeometric coherent states

    International Nuclear Information System (INIS)

    Appl, Thomas; Schiller, Diethard H

    2004-01-01

    We introduce a large class of holomorphic quantum states by choosing their normalization functions to be given by generalized hypergeometric functions. We call them generalized hypergeometric states in general, and generalized hypergeometric coherent states in particular, if they allow a resolution of unity. Depending on the domain of convergence of the generalized hypergeometric functions, we distinguish generalized hypergeometric states on the plane, the open unit disc and the unit circle. All states are eigenstates of suitably defined lowering operators. We then study their photon number statistics and phase properties as revealed by the Husimi and Pegg-Barnett phase distributions. On the basis of the generalized hypergeometric coherent states we introduce new analytic representations of arbitrary quantum states in Bargmann and Hardy spaces as well as generalized hypergeometric Husimi distributions and corresponding phase distributions

  3. HYPERDIRE. HYPERgeometric functions DIfferential REduction. MATHEMATICA based packages for differential reduction of generalized hypergeometric functions {sub p}F{sub p-1}, F{sub 1}, F{sub 2}, F{sub 3}, F{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Bytev, Vladimir V.; Kalmykov, Mikhail Yu. [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Joint Institute for Nuclear Research, Dubna (Russian Federation); Kniehl, Bernd A. [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik

    2013-05-15

    HYPERDIRE is a project devoted to the creation of a set of Mathematica based programs for the differential reduction of hypergeometric functions. The current version includes two parts: one, pfq, is relevant for manipulations of hypergeometric functions {sub p+1}F{sub p}, and the second one, AppellF1F4, for manipulations with Appell hypergeometric functions F{sub 1}, F{sub 2}, F{sub 3}, F{sub 4} of two variables.

  4. Differential reduction of generalized hypergeometric functions from Feynman diagrams. One-variable case

    Energy Technology Data Exchange (ETDEWEB)

    Bytev, Vladimir V.; Kalmykov, Mikhail Yu.; Kniehl, Bernd A. [Hamburg Univ. (Germany). II. Inst. fuer Theoretische Physik

    2010-03-15

    The differential-reduction algorithm, which allows one to express generalized hypergeometric functions with parameters of arbitrary values in terms of such functions with parameters whose values differ from the original ones by integers, is discussed in the context of evaluating Feynman diagrams. Where this is possible, we compare our results with those obtained using standard techniques. It is shown that the criterion of reducibility of multiloop Feynman integrals can be reformulated in terms of the criterion of reducibility of hypergeometric functions. The relation between the numbers of master integrals obtained by differential reduction and integration by parts is discussed. (orig.)

  5. GKZ Hypergeometric Structures

    NARCIS (Netherlands)

    Stienstra, J.

    2007-01-01

    This text is based on lectures by the author in the Summer School Algebraic Geometry and Hypergeometric Functions in Istanbul in June 2005. It gives a review of some of the basic aspects of the theory of hypergeometric structures of Gelfand, Kapranov and Zelevinsky, including Differential

  6. Certain Integral Transform and Fractional Integral Formulas for the Generalized Gauss Hypergeometric Functions

    Directory of Open Access Journals (Sweden)

    Junesang Choi

    2014-01-01

    Full Text Available A remarkably large number of integral transforms and fractional integral formulas involving various special functions have been investigated by many authors. Very recently, Agarwal gave some integral transforms and fractional integral formulas involving the Fp(α,β(·. In this sequel, using the same technique, we establish certain integral transforms and fractional integral formulas for the generalized Gauss hypergeometric functions Fp(α,β,m(·. Some interesting special cases of our main results are also considered.

  7. Evaluation of integrals with hypergeometric and logarithmic functions

    Directory of Open Access Journals (Sweden)

    Sofo Anthony

    2018-02-01

    Full Text Available We provide an explicit analytical representation for a number of logarithmic integrals in terms of the Lerch transcendent function and other special functions. The integrals in question will be associated with both alternating harmonic numbers and harmonic numbers with positive terms. A few examples of integrals will be given an identity in terms of some special functions including the Riemann zeta function. In general none of these integrals can be solved by any currently available mathematical package.

  8. On Approximation of Hyper-geometric Function Values of a Special Class

    Directory of Open Access Journals (Sweden)

    P. L. Ivankov

    2017-01-01

    Full Text Available Investigations of arithmetic properties of the hyper-geometric function values make it possible to single out two trends, namely, Siegel’s method and methods based on the effective construction of a linear approximating form. There are also methods combining both approaches mentioned.  The Siegel’s method allows obtaining the most general results concerning the abovementioned problems. In many cases it was used to establish the algebraic independence of the values of corresponding functions. Although the effective methods do not allow obtaining propositions of such generality they have nevertheless some advantages. Among these advantages one can distinguish at least two: a higher precision of the quantitative results obtained by effective methods and a possibility to study the hyper-geometric functions with irrational parameters.In this paper we apply the effective construction to estimate a measure of the linear independence of the hyper-geometric function values over the imaginary quadratic field. The functions themselves were chosen by a special way so that it could be possible to demonstrate a new approach to the effective construction of a linear approximating form. This approach makes it possible also to extend the well-known effective construction methods of the linear approximating forms for poly-logarithms to the functions of more general type.To obtain the arithmetic result we had to establish a linear independence of the functions under consideration over the field of rational functions. It is apparently impossible to apply directly known theorems containing sufficient (and in some cases needful and sufficient conditions for the system of functions appearing in the theorems mentioned. For this reason, a special technique has been developed to solve this problem.The paper presents the obtained arithmetic results concerning the values of integral functions, but, with appropriate alterations, the theorems proved can be adapted to

  9. Composite fields, generalized hypergeometric functions and the U(1)Y symmetry in the AdS/CFT correspondence

    International Nuclear Information System (INIS)

    Hoffmann, L.; Leonhardt, T.; Mesref, L.; Ruehl, W.

    2001-01-01

    We discuss the concept of composite fields in flat CFT as well as in the context of AdS/CFT. Furthermore we show how to represent Green functions using generalized hypergeometric functions and apply these techniques to four-point functions. Finally we prove an identity of U(1) Y symmetry for four-point functions

  10. Composite fields, generalized hypergeometric functions and the U(1)Y symmetry in the AdS/CFT correspondence

    Science.gov (United States)

    Hoffmann, L.; Leonhardt, T.; Mesref, L.; Rühl, W.

    2001-09-01

    We discuss the concept of composite fields in flat CFT as well as in the context of AdS/CFT. Furthermore we show how to represent Green functions using generalized hypergeometric functions and apply these techniques to four-point functions. Finally we prove an identity of U(1)Y symmetry for four-point functions.

  11. Towards all-order Laurent expansion of generalized hypergeometric functions around rational values of parameters

    Energy Technology Data Exchange (ETDEWEB)

    Kalmykov, M.Yu.; Kniehl, B.A. [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik

    2008-07-15

    We prove the following theorems: 1) The Laurent expansions in {epsilon} of the Gauss hypergeometric functions {sub 2}F{sub 1}(I{sub 1}+a{epsilon},I{sub 2}+b{epsilon};I{sub 3}+(p)/(q)+c{epsilon};z), {sub 2}F{sub 1}(I{sub 1}+(p)/(q)+a{epsilon},I{sub 2}+(p/q)+b{epsilon};I{sub 3}+(p)/(q)+c{epsilon};z) and {sub 2}F{sub 1}(I{sub 1}+(p)/(q)+ a{epsilon},I{sub 2}+b{epsilon};I{sub 3}+(p)/(q)+c{epsilon};z), where I{sub 1},I{sub 2},I{sub 3},p,q are arbitrary integers, a,b,c are arbitrary numbers and {epsilon} is an infinitesimal parameter, are expressible in terms of multiple polylogarithms of q-roots of unity with coefficients that are ratios of polynomials; 2) The Laurent expansion of the Gauss hypergeometric function {sub 2}F{sub 1}(I{sub 1}+(p)/(q)+a{epsilon},I{sub 2}+b{epsilon};I{sub 3}+c{epsilon};z) is expressible in terms of multiple polylogarithms of q-roots of unity times powers of logarithm with coefficients that are ratios of polynomials; 3) The multiple inverse rational sums {sigma}{sup {infinity}}{sub j=1}({gamma}(j))/({gamma}(1+j-(p)/(q))) (z{sup j})/(j{sup c}) S{sub a{sub 1}}(j-1).. S{sub a{sub p}}(j-1) and the multiple rational sums {sigma}{sup {infinity}}{sub j=1} ({gamma}(j+(p)/(q)))/({gamma}(1+j)) (z{sup j})/(j{sup c}) S{sub a{sub 1}}(j-1).. S{sub a{sub p}}(j-1), where S{sub a}(j)={sigma}{sup j}{sub k=1}(1)/(k{sup a}) is a harmonic series and c is an arbitrary integer, are expressible in terms of multiple polylogarithms; 4) The generalized hypergeometric functions {sub p}F{sub p.1}((vector)A+(vector)a{epsilon};(vector)B+(vector)b{epsilon},(p)/(q)+B{sub p-1};z) and {sub p}F{sub p-1}((vector)A+(vector)a{epsilon},(p)/(q)+A{sub p};(vector)B+(vector)b{epsilon};z) are expressible in terms of multiple polylogarithms with coefficients that are ratios of polynomials. (orig.)

  12. The star-triangle relation, lens partition function, and hypergeometric sum/integrals

    Energy Technology Data Exchange (ETDEWEB)

    Gahramanov, Ilmar [Max Planck Institute for Gravitational Physics (Albert Einstein Institute),Am Mühlenberg 1, D-14476 Potsdam (Germany); Institute of Radiation Problems ANAS,B. Vahabzade 9, AZ1143 Baku (Azerbaijan); Department of Mathematics, Khazar University,Mehseti St. 41, AZ1096 Baku (Azerbaijan); Kels, Andrew P. [Institute of Physics, University of Tokyo,Komaba, Tokyo 153-8902 (Japan)

    2017-02-08

    The aim of the present paper is to consider the hyperbolic limit of an elliptic hypergeometric sum/integral identity, and associated lattice model of statistical mechanics previously obtained by the second author. The hyperbolic sum/integral identity obtained from this limit, has two important physical applications in the context of the so-called gauge/YBE correspondence. For statistical mechanics, this identity is equivalent to a new solution of the star-triangle relation form of the Yang-Baxter equation, that directly generalises the Faddeev-Volkov models to the case of discrete and continuous spin variables. On the gauge theory side, this identity represents the duality of lens (S{sub b}{sup 3}/ℤ{sub r}) partition functions, for certain three-dimensional N=2 supersymmetric gauge theories.

  13. The star-triangle relation, lens partition function, and hypergeometric sum/integrals

    International Nuclear Information System (INIS)

    Gahramanov, Ilmar; Kels, Andrew P.

    2017-01-01

    The aim of the present paper is to consider the hyperbolic limit of an elliptic hypergeometric sum/integral identity, and associated lattice model of statistical mechanics previously obtained by the second author. The hyperbolic sum/integral identity obtained from this limit, has two important physical applications in the context of the so-called gauge/YBE correspondence. For statistical mechanics, this identity is equivalent to a new solution of the star-triangle relation form of the Yang-Baxter equation, that directly generalises the Faddeev-Volkov models to the case of discrete and continuous spin variables. On the gauge theory side, this identity represents the duality of lens (S b 3 /ℤ r ) partition functions, for certain three-dimensional N=2 supersymmetric gauge theories.

  14. Observations on the summability of confluent hypergeometric functions and on semiclassical quantum mechanics

    Energy Technology Data Exchange (ETDEWEB)

    Silverstone, H.J.; Nakai, S.; Harris, J.G.

    1985-09-01

    Asymptotic expansions for Airy functions and more generally confluent hypergeometric functions, which are of fundamental importance in semiclassical quantum mechanics, are summable. The Stokes lines of the expansions are cuts of the Borel sums of the power series occurring in the expansions. At a Stokes line on which the function is continuous, the asymptotic expansions change discontinuously, but their composite sums do not: a fact that greatly clarifies the role of the Stokes line. On a Stokes line itself, it is still possible to evaluate the asymptotic expansion by Borel summation via analytic continuation, and as a consequence complex expansions may have real sums, and vice versa. This observation has important implications for the significance and use of asymptotic expansions recently derived for the resonances of the LoSurdo-Stark effect and for the energy eigenvalues of H/sub 2/ /sup +/. For both of these problems the physical values of the expansion parameters, the electric field strength and the reciprocal of the internuclear distance, lie on Stokes lines.

  15. Complex curve of the two-matrix model and its tau-function

    International Nuclear Information System (INIS)

    Kazakov, Vladimir A; Marshakov, Andrei

    2003-01-01

    We study the Hermitian and normal two-matrix models in planar approximation for an arbitrary number of eigenvalue supports. Its planar graph interpretation is given. The study reveals a general structure of the underlying analytic complex curve, different from the hyperelliptic curve of the one-matrix model. The matrix model quantities are expressed through the periods of meromorphic generating differential on this curve and the partition function of the multiple support solution, as a function of filling numbers and coefficients of the matrix potential, is shown to be a quasiclassical tau-function. The relation to N = 1 supersymmetric Yang-Mills theories is discussed. A general class of solvable multi-matrix models with tree-like interactions is considered

  16. Special values of the hypergeometric series

    CERN Document Server

    Ebisu, Akihito

    2017-01-01

    In this paper, the author presents a new method for finding identities for hypergeoemtric series, such as the (Gauss) hypergeometric series, the generalized hypergeometric series and the Appell-Lauricella hypergeometric series. Furthermore, using this method, the author gets identities for the hypergeometric series F(a,b;c;x) and shows that values of F(a,b;c;x) at some points x can be expressed in terms of gamma functions, together with certain elementary functions. The author tabulates the values of F(a,b;c;x) that can be obtained with this method and finds that this set includes almost all previously known values and many previously unknown values.

  17. Basic hypergeometric functions and covariant spaces for even-dimensional representations of Uq[osp(1/2)

    International Nuclear Information System (INIS)

    Aizawa, N; Chakrabarti, R; Mohammed, S S Naina; Segar, J

    2007-01-01

    Representations of the quantum superalgebra U q [osp(1/2)] and their relations to the basic hypergeometric functions are investigated. We first establish Clebsch-Gordan decomposition for the superalgebra U q [osp(1/2)] in which the representations having no classical counterparts are incorporated. Formulae for these Clebsch-Gordan coefficients are derived, and is observed that they may be expressed in terms of the Q-Hahn polynomials. We next investigate representations of the quantum supergroup OSp q (1/2) which are not well defined in the classical limit. Employing the universal T-matrix, the representation matrices are obtained explicitly, and found to be related to the little Q-Jacobi polynomials. Characteristically, the relation Q = -q is satisfied in all cases. Using the Clebsch-Gordan coefficients derived here, we construct new noncommutative spaces that are covariant under the coaction of the even-dimensional representations of the quantum supergroup OSp q (1/2)

  18. An application of hypergeometric functions to a problem in function theory

    Directory of Open Access Journals (Sweden)

    Daniel S. Moak

    1984-01-01

    Full Text Available In some recent work in univalent function theory, Aharonov, Friedland, and Brannan studied the series (1+xtα(1−tβ=∑n=0∞An(α,β(xtn. Brannan posed the problem of determining S={(α,β:|An(α,β(eiθ|0,   β>0,   n=1,2,3,…}. Brannan showed that if β≥α≥0, and α+β≥2, then (α,β∈S. He also proved that (α,1∈S for α≥1. Brannan showed that for 0|A2k(α,1(1| for k any integer. In this paper, we show that (α,β∈S for α≥1 and β≥1.

  19. On Generalized Fractional Integral Operators and the Generalized Gauss Hypergeometric Functions

    Directory of Open Access Journals (Sweden)

    Dumitru Baleanu

    2014-01-01

    Full Text Available A remarkably large number of fractional integral formulas involving the number of special functions, have been investigated by many authors. Very recently, Agarwal (National Academy Science Letters gave some integral transform and fractional integral formulas involving the Fpα,β·. In this sequel, here, we aim to establish some image formulas by applying generalized operators of the fractional integration involving Appell’s function F3(· due to Marichev-Saigo-Maeda. Some interesting special cases of our main results are also considered.

  20. Representation of the Coulomb Matrix Elements by Means of Appell Hypergeometric Function F 2

    Science.gov (United States)

    Bentalha, Zine el abidine

    2018-06-01

    Exact analytical representation for the Coulomb matrix elements by means of Appell's double series F 2 is derived. The finite sum obtained for the Appell function F 2 allows us to evaluate explicitly the matrix elements of the two-body Coulomb interaction in the lowest Landau level. An application requiring the matrix elements of Coulomb potential in quantum Hall effect regime is presented.

  1. Numerically satisfactory solutions of hypergeometric recursions

    NARCIS (Netherlands)

    A. Gil (Amparo); J. Segura (Javier); N.M. Temme (Nico)

    2007-01-01

    textabstractEach family of Gauss hypergeometric functions $$ f_n={}_2F_1(a+\\varepsilon_1n, b+\\varepsilon_2n ;c+\\varepsilon_3n; z),\\quad n\\in {\\mathbb Z}\\,, $$ for fixed $\\varepsilon_j=0,\\pm1$ (not all $\\varepsilon_j$ equal to zero) satisfies a second order linear difference equation of the

  2. Numerically satisfactory solutions of hypergeometric recursions

    NARCIS (Netherlands)

    A. Gil (Amparo); J. Segura (Javier); N.M. Temme (Nico)

    2006-01-01

    textabstractEach family of Gauss hypergeometric functions $f_n = 2F_1(a+epsilon 1n,b+epsilon 2n;c+epsilon 3n;z), nin Z$, for fixed epsilon_j = 0,pm 1$ (not all epsilon j equal to zero) satisfies a second order linear difference equation of the form $A_n f_{n-1} + B_n f_n + C_n f_{n+1} = 0$. Because

  3. Multivariable hypergeometric solutions for three charged particles

    Energy Technology Data Exchange (ETDEWEB)

    Gasaneo, G.; Colavecchia, F.D.; Garibotti, C.R. [Comision Nacional de Energia Atomica, San Carlos de Bariloche (Argentina). Centro Atomico Bariloche]|[Consejo Nacional de Investigaciones Cientificas y Tecnicas, San Carlos de Bariloche (Argentina); Miraglia, J.E.; Macri, P. [IAFE, Consejo de Investigaciones Cientificas y Tecnicas, Buenos Aires (Argentina)

    1997-04-28

    We present a new wavefunction which describes the ion-atom problem above the ionization threshold. This is an approximate solution of the Schrodinger equation for the three-body Coulomb problem that can be expressed in terms of a confluent hypergeometric function of two variables. The proposed wavefunction includes correlation among the motions of the three particles and verifies the correct Coulombic asymptotic behaviours. (author).

  4. From the hypergeometric differential equation to a non-linear Schrödinger one

    International Nuclear Information System (INIS)

    Plastino, A.; Rocca, M.C.

    2015-01-01

    We show that the q-exponential function is a hypergeometric function. Accordingly, it obeys the hypergeometric differential equation. We demonstrate that this differential equation can be transformed into a non-linear Schrödinger equation (NLSE). This NLSE exhibits both similarities and differences vis-a-vis the Nobre–Rego-Monteiro–Tsallis one. - Highlights: • We show that the q-exponential is a hypergeometric function. • It thus obeys the hypergeometric differential equation (HDE). • We show that the HDE can be cast as a non-linear Schrödinger equation. • This is different from the Nobre, Rego-Monteiro, Tsallis one.

  5. Calculation Methods for Wallenius’ Noncentral Hypergeometric Distribution

    DEFF Research Database (Denmark)

    Fog, Agner

    2008-01-01

    Two different probability distributions are both known in the literature as "the" noncentral hypergeometric distribution. Wallenius' noncentral hypergeometric distribution can be described by an urn model without replacement with bias. Fisher's noncentral hypergeometric distribution...... is the conditional distribution of independent binomial variates given their sum. No reliable calculation method for Wallenius' noncentral hypergeometric distribution has hitherto been described in the literature. Several new methods for calculating probabilities from Wallenius' noncentral hypergeometric...... distribution are derived. Range of applicability, numerical problems, and efficiency are discussed for each method. Approximations to the mean and variance are also discussed. This distribution has important applications in models of biased sampling and in models of evolutionary systems....

  6. Classification of hypergeometric identities for pi and other logarithms of algebraic numbers.

    Science.gov (United States)

    Chudnovsky, D V; Chudnovsky, G V

    1998-03-17

    This paper provides transcendental and algebraic framework for the classification of identities expressing pi and other logarithms of algebraic numbers as rapidly convergent generalized hypergeometric series in rational parameters. Algebraic and arithmetic relations between values of p+1Fp hypergeometric functions and their values are analyzed. The existing identities are explained, and new exhaustive classes of new ones are presented.

  7. Some Instructional Issues in Hypergeometric Distribution

    Directory of Open Access Journals (Sweden)

    Anwar H. Joarder

    2012-07-01

    Full Text Available 800x600 Normal 0 false false false EN-US X-NONE X-NONE A brief introduction to sampling without replacement is presented. We represent the probability of a sample outcome in sampling without replacement from a finite population by three equivalent forms involving permutation and combination. Then it is used to calculate the probability of any number of successes in a given sample. The resulting forms are equivalent to the well known mass function of the hypergeometric distribution. Vandermonde’s identity readily justifies different forms of the mass function. One of the new form of the mass function embodies binomial coefficient showing much resemblance to that of binomial distribution. It also yields some interesting identities. Some other related issues are discussed.

  8. SOME PROPERTIES OF HORN TYPE SECOND ORDER DOUBLE HYPERGEOMETRIC SERIES

    Directory of Open Access Journals (Sweden)

    Anvar Hasanov

    2018-04-01

    Full Text Available Horn [1931, Hypergeometrische Funktionen zweier Veranderlichen, Math. Ann.,105(1, 381-407], (corrections in Borngasser [1933, Uber hypergeometrische funkionen zweier Veranderlichen, Dissertation, Darmstadt], defined and investigated ten second order hypergeometric series of two variables. In the course of further investigation of Horn’s series, we noticed the existence of hypergeometric double series H*2 analogous to Horn’s double series H*2. The principal object of this paper is to present a natural further step toward the mathematical properties and presentations concerning the analogous hypergeometric double series H*2 Indeed, motivated by the important role of the Horn’s functions in several diverse fields of physics and the contributions toward the unification and generalization of the hyper-geometric functions, we establish a system of partial differential equations, integral representations, expansions, analytic continuation, transformation formulas and generating relations. Also, we discuss the links for the various results, which are presented in this paper, with known results.

  9. Particular Solutions of the Confluent Hypergeometric Differential Equation by Using the Nabla Fractional Calculus Operator

    Directory of Open Access Journals (Sweden)

    Resat Yilmazer

    2016-02-01

    Full Text Available In this work; we present a method for solving the second-order linear ordinary differential equation of hypergeometric type. The solutions of this equation are given by the confluent hypergeometric functions (CHFs. Unlike previous studies, we obtain some different new solutions of the equation without using the CHFs. Therefore, we obtain new discrete fractional solutions of the homogeneous and non-homogeneous confluent hypergeometric differential equation (CHE by using a discrete fractional Nabla calculus operator. Thus, we obtain four different new discrete complex fractional solutions for these equations.

  10. A two-matrix alternative

    Czech Academy of Sciences Publication Activity Database

    Rohn, Jiří

    2013-01-01

    Roč. 26, 15 December (2013), s. 836-841 ISSN 1537-9582 Institutional support: RVO:67985807 Keywords : two-matrix alternative * solution * algorithm Subject RIV: BA - General Mathematics Impact factor: 0.514, year: 2013 http://www.math.technion.ac.il/iic/ ela / ela -articles/articles/vol26_pp836-841.pdf

  11. One loop integration with hypergeometric series by using recursion relations

    International Nuclear Information System (INIS)

    Watanabe, Norihisa; Kaneko, Toshiaki

    2014-01-01

    General one-loop integrals with arbitrary mass and kinematical parameters in d-dimensional space-time are studied. By using Bernstein theorem, a recursion relation is obtained which connects (n + 1)-point to n-point functions. In solving this recursion relation, we have shown that one-loop integrals are expressed by a newly defined hypergeometric function, which is a special case of Aomoto-Gelfand hypergeometric functions. We have also obtained coefficients of power series expansion around 4-dimensional space-time for two-, three- and four-point functions. The numerical results are compared with ''LoopTools'' for the case of two- and three-point functions as examples

  12. Hypergeometric continuation of divergent perturbation series: II. Comparison with Shanks transformation and Padé approximation

    International Nuclear Information System (INIS)

    Sanders, Sören; Holthaus, Martin

    2017-01-01

    We explore in detail how analytic continuation of divergent perturbation series by generalized hypergeometric functions is achieved in practice. Using the example of strong-coupling perturbation series provided by the two-dimensional Bose–Hubbard model, we compare hypergeometric continuation to Shanks and Padé techniques, and demonstrate that the former yields a powerful, efficient and reliable alternative for computing the phase diagram of the Mott insulator-to-superfluid transition. In contrast to Shanks transformations and Padé approximations, hypergeometric continuation also allows us to determine the exponents which characterize the divergence of correlation functions at the transition points. Therefore, hypergeometric continuation constitutes a promising tool for the study of quantum phase transitions. (paper)

  13. Hypergeometric continuation of divergent perturbation series: II. Comparison with Shanks transformation and Padé approximation

    Science.gov (United States)

    Sanders, Sören; Holthaus, Martin

    2017-11-01

    We explore in detail how analytic continuation of divergent perturbation series by generalized hypergeometric functions is achieved in practice. Using the example of strong-coupling perturbation series provided by the two-dimensional Bose-Hubbard model, we compare hypergeometric continuation to Shanks and Padé techniques, and demonstrate that the former yields a powerful, efficient and reliable alternative for computing the phase diagram of the Mott insulator-to-superfluid transition. In contrast to Shanks transformations and Padé approximations, hypergeometric continuation also allows us to determine the exponents which characterize the divergence of correlation functions at the transition points. Therefore, hypergeometric continuation constitutes a promising tool for the study of quantum phase transitions.

  14. Auto-focusing accelerating hyper-geometric laser beams

    International Nuclear Information System (INIS)

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

    2016-01-01

    We derive a new solution to the paraxial wave equation that defines a two-parameter family of three-dimensional structurally stable vortex annular auto-focusing hyper-geometric (AH) beams, with their complex amplitude expressed via a degenerate hyper-geometric function. The AH beams are found to carry an orbital angular momentum and be auto-focusing, propagating on an accelerating path toward a focus, where the annular intensity pattern is ‘sharply’ reduced in diameter. An explicit expression for the complex amplitude of vortex annular auto-focusing hyper-geometric-Gaussian beams is derived. The experiment has been shown to be in good agreement with theory. (paper)

  15. Two-matrix models and c =1 string theory

    International Nuclear Information System (INIS)

    Bonora, L.; Xiong Chuansheng

    1994-05-01

    We show that the most general two-matrix model with bilinear coupling underlies c = 1 string theory. More precisely we prove that W 1+∞ constraints, a subset of the correlation functions and the integrable hierarchy characterizing such two-matrix model, correspond exactly to the W 1+∞ constraints, to the discrete tachyon correlation functions and the integrable hierarchy of the c = 1 string theory. (orig.)

  16. The Lambert-W step-potential – an exactly solvable confluent hypergeometric potential

    Energy Technology Data Exchange (ETDEWEB)

    Ishkhanyan, A.M., E-mail: aishkhanyan@gmail.com [Institute for Physical Research, NAS of Armenia, 0203 Ashtarak (Armenia); Armenian State Pedagogical University, 0010 Yerevan (Armenia); Institute of Physics and Technology, National Research Tomsk Polytechnic University, Tomsk 634050 (Russian Federation)

    2016-02-15

    We present an asymmetric step–barrier potential for which the one-dimensional stationary Schrödinger equation is exactly solved in terms of the confluent hypergeometric functions. The potential is given in terms of the Lambert W-function, which is an implicitly elementary function also known as the product logarithm. We present the general solution of the problem and consider the quantum reflection at transmission of a particle above this potential barrier. Compared with the abrupt-step and hyperbolic tangent potentials, which are reproduced by the Lambert potential in certain parameter and/or variable variation regions, the reflection coefficient is smaller because of the lesser steepness of the potential on the particle incidence side. Presenting the derivation of the Lambert potential we show that this is a four-parametric sub-potential of a more general five-parametric one also solvable in terms of the confluent hypergeometric functions. The latter potential, however, is a conditionally integrable one. Finally, we show that there exists one more potential the solution for which is written in terms of the derivative of a bi-confluent Heun function. - Highlights: • We introduce an asymmetric step-barrier potential for which the 1D Schrödinger equation is exactly solved in terms of confluent hypergeometric functions. • The potential is given in terms of the Lambert-function, which is an implicitly elementary function also known as the product logarithm. • This is a four-parametric specification of a more general five-parametric potential also solvable in terms of the confluent hypergeometric functions. • There exists one more potential the solution for which is written in terms of the derivative of a bi-confluent Heun function.

  17. Index hypergeometric transform and imitation of analysis of Berezin kernels on hyperbolic spaces

    International Nuclear Information System (INIS)

    Neretin, Yu A

    2001-01-01

    The index hypergeometric transform (also called the Olevskii transform or the Jacobi transform) generalizes the spherical transform in L 2 on rank 1 symmetric spaces (that is, real, complex, and quaternionic Lobachevskii spaces). The aim of this paper is to obtain properties of the index hypergeometric transform imitating the analysis of Berezin kernels on rank 1 symmetric spaces. The problem of the explicit construction of a unitary operator identifying L 2 and a Berezin space is also discussed. This problem reduces to an integral expression (the Λ-function), which apparently cannot be expressed in a finite form in terms of standard special functions. (Only for certain special values of the parameter can this expression be reduced to the so-called Volterra type special functions.) Properties of this expression are investigated. For some series of symmetric spaces of large rank the above operator of unitary equivalence can be expressed in terms of the determinant of a matrix of Λ-functions

  18. Fractional Fourier transform for confluent hypergeometric beams

    International Nuclear Information System (INIS)

    Tang, Bin; Jiang, Chun; Zhu, Haibin

    2012-01-01

    Based on the definition of the fractional Fourier transform (FRFT) in the cylindrical coordinate system, the propagation properties of a new family of paraxial laser beams named confluent hypergeometric (HyG) beams, of which intensity profile is similar to that for the Bessel modes, passing through FRFT optical systems have been studied in detail by some typical numerical examples. The results indicate that the normalized intensity distribution of a HyG beam in the FRFT plane is closely related to not only the fractional order p but also the beam parameters m,n, and focal length f. -- Highlights: ► We study the propagation of a HyG beam through FRFT optical systems. ► The intensity of the beam in the FRFT plane is closely related to some parameters. ► We can control the properties of HyG beams by properly choosing the parameters.

  19. Algunas integrales impropias con límites de integración infinitos que involucran a la generalización τ de la función hipergeométrica de Gauss Some improper integrals with integration infinity limit involving generalizad hypergeometric function 2R1(a, b; c; τ ; z

    Directory of Open Access Journals (Sweden)

    Jaime Castillo Pérez

    2007-06-01

    Full Text Available En 1991 M. Dotsenko presentó una generalización de la función hipergeométrica de Gauss denotada por 2Rτ1 (z, estableciendo además tanto su representación en serie como también su representación integral. Es importante notar que en 1999 Nina Virchenko y luego, en el 2003, Leda Galué consideraron esta función, introduciendo un conjunto de fórmulas de recurrencia y de diferenciación las cuales permiten simplificar algunos cálculos complicados. Kalla y colaboradores estudiaron esta función y presentaron una nueva forma unificada de la función Gamma, luego en el 2006, Castillo y colaboradores presentaron algunas representaciones simples para ésta función. En este trabajo se establecen algunas integrales impropias con límites de integración infinitos que involucran a la generalización τ de la función hipergeométrica de Gauss 2R1(a, b; c; τ ; z.In 1991 M. Dotsenko presented a generalization of Gauss’ hypergeometric function refered as 2Rτ1(z, and established its representation in series and integral. It is important to remark that in 1999 Nina Virchenko and, later in 2003, Leda Galu´e considered this function by introducing a set of recurrence and differentiation formulas; they permit simplify some complicated calculus. Kalla et al estudied this function and they presented a new unified form of the gamma function. Later in 2006, Castillo et al present some simple representation for this function. Along this paper work some improper integrals with integration infinity limit involving generalized hypergeometric function2R1(a, b; c; τ ; z are displayed.

  20. The exact equation of motion of a simple pendulum of arbitrary amplitude: a hypergeometric approach

    International Nuclear Information System (INIS)

    Qureshi, M I; Rafat, M; Azad, S Ismail

    2010-01-01

    The motion of a simple pendulum of arbitrary amplitude is usually treated by approximate methods. By using generalized hypergeometric functions, it is however possible to solve the problem exactly. In this paper, we provide the exact equation of motion of a simple pendulum of arbitrary amplitude. A new and exact expression for the time of swinging of a simple pendulum from the vertical position to an arbitrary angular position θ is given by equation (3.10). The time period of such a pendulum is also exactly expressible in terms of hypergeometric functions. The exact expressions thus obtained are used to plot the graphs that compare the exact time period T(θ 0 ) with the time period T(0) (based on simple harmonic approximation). We also compare the relative difference between T(0) and T(θ 0 ) found from the exact equation of motion with the usual perturbation theory estimate. The treatment is intended for graduate students, who have acquired some familiarity with the hypergeometric functions. This approach may also be profitably used by specialists who encounter during their investigations nonlinear differential equations similar in form to the pendulum equation. Such nonlinear differential equations could arise in diverse fields, such as acoustic vibrations, oscillations in small molecules, turbulence and electronic filters, among others.

  1. Development of sample size allocation program using hypergeometric distribution

    International Nuclear Information System (INIS)

    Kim, Hyun Tae; Kwack, Eun Ho; Park, Wan Soo; Min, Kyung Soo; Park, Chan Sik

    1996-01-01

    The objective of this research is the development of sample allocation program using hypergeometric distribution with objected-oriented method. When IAEA(International Atomic Energy Agency) performs inspection, it simply applies a standard binomial distribution which describes sampling with replacement instead of a hypergeometric distribution which describes sampling without replacement in sample allocation to up to three verification methods. The objective of the IAEA inspection is the timely detection of diversion of significant quantities of nuclear material, therefore game theory is applied to its sampling plan. It is necessary to use hypergeometric distribution directly or approximate distribution to secure statistical accuracy. Improved binomial approximation developed by Mr. J. L. Jaech and correctly applied binomial approximation are more closer to hypergeometric distribution in sample size calculation than the simply applied binomial approximation of the IAEA. Object-oriented programs of 1. sample approximate-allocation with correctly applied standard binomial approximation, 2. sample approximate-allocation with improved binomial approximation, and 3. sample approximate-allocation with hypergeometric distribution were developed with Visual C ++ and corresponding programs were developed with EXCEL(using Visual Basic for Application). 8 tabs., 15 refs. (Author)

  2. Iterated elliptic and hypergeometric integrals for Feynman diagrams

    Energy Technology Data Exchange (ETDEWEB)

    Ablinger, J.; Radu, C.S.; Schneider, C. [Johannes Kepler Univ., Linz (Austria). Research Inst. for Symbolic Computation (RISC); Bluemlein, J.; Freitas, A. de [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Van Hoeij, M.; Imamoglu, E. [Florida State Univ., Tallahassee, FL (United States). Dept. of Mathematics; Raab, C.G. [Linz Univ. (Austria). Inst. for Algebra

    2017-05-15

    We calculate 3-loop master integrals for heavy quark correlators and the 3-loop QCD corrections to the ρ-parameter. They obey non-factorizing differential equations of second order with more than three singularities, which cannot be factorized in Mellin-N space either. The solution of the homogeneous equations is possible in terms of convergent close integer power series as {sub 2}F{sub 1} Gauss hypergeometric functions at rational argument. In some cases, integrals of this type can be mapped to complete elliptic integrals at rational argument. This class of functions appears to be the next one arising in the calculation of more complicated Feynman integrals following the harmonic polylogarithms, generalized polylogarithms, cyclotomic harmonic polylogarithms, square-root valued iterated integrals, and combinations thereof, which appear in simpler cases. The inhomogeneous solution of the corresponding differential equations can be given in terms of iterative integrals, where the new innermost letter itself is not an iterative integral. A new class of iterative integrals is introduced containing letters in which (multiple) definite integrals appear as factors. For the elliptic case, we also derive the solution in terms of integrals over modular functions and also modular forms, using q-product and series representations implied by Jacobi's θ{sub i} functions and Dedekind's η-function. The corresponding representations can be traced back to polynomials out of Lambert-Eisenstein series, having representations also as elliptic polylogarithms, a q-factorial 1/η{sup κ}(τ), logarithms and polylogarithms of q and their q-integrals. Due to the specific form of the physical variable x(q) for different processes, different representations do usually appear. Numerical results are also presented.

  3. Iterated elliptic and hypergeometric integrals for Feynman diagrams

    International Nuclear Information System (INIS)

    Ablinger, J.; Radu, C.S.; Schneider, C.; Bluemlein, J.; Freitas, A. de; Van Hoeij, M.; Imamoglu, E.; Raab, C.G.

    2017-05-01

    We calculate 3-loop master integrals for heavy quark correlators and the 3-loop QCD corrections to the ρ-parameter. They obey non-factorizing differential equations of second order with more than three singularities, which cannot be factorized in Mellin-N space either. The solution of the homogeneous equations is possible in terms of convergent close integer power series as _2F_1 Gauss hypergeometric functions at rational argument. In some cases, integrals of this type can be mapped to complete elliptic integrals at rational argument. This class of functions appears to be the next one arising in the calculation of more complicated Feynman integrals following the harmonic polylogarithms, generalized polylogarithms, cyclotomic harmonic polylogarithms, square-root valued iterated integrals, and combinations thereof, which appear in simpler cases. The inhomogeneous solution of the corresponding differential equations can be given in terms of iterative integrals, where the new innermost letter itself is not an iterative integral. A new class of iterative integrals is introduced containing letters in which (multiple) definite integrals appear as factors. For the elliptic case, we also derive the solution in terms of integrals over modular functions and also modular forms, using q-product and series representations implied by Jacobi's θ_i functions and Dedekind's η-function. The corresponding representations can be traced back to polynomials out of Lambert-Eisenstein series, having representations also as elliptic polylogarithms, a q-factorial 1/η"κ(τ), logarithms and polylogarithms of q and their q-integrals. Due to the specific form of the physical variable x(q) for different processes, different representations do usually appear. Numerical results are also presented.

  4. Distinguishing between Binomial, Hypergeometric and Negative Binomial Distributions

    Science.gov (United States)

    Wroughton, Jacqueline; Cole, Tarah

    2013-01-01

    Recognizing the differences between three discrete distributions (Binomial, Hypergeometric and Negative Binomial) can be challenging for students. We present an activity designed to help students differentiate among these distributions. In addition, we present assessment results in the form of pre- and post-tests that were designed to assess the…

  5. An asymptotic formula of the divergent bilateral basic hypergeometric series

    OpenAIRE

    Morita, Takeshi

    2012-01-01

    We show an asymptotic formula of the divergent bilateral basic hypergeometric series ${}_1\\psi_0 (a;-;q,\\cdot)$ with using the $q$-Borel-Laplace method. We also give the limit $q\\to 1-0$ of our asymptotic formula.

  6. Some New Formulas for the Generalized Hypergeometric Series

    Directory of Open Access Journals (Sweden)

    Sumi P. Krishnan

    Full Text Available The aim of this research paper is to provide some new formulas for the generalized hypergeometric series. The results are derived with the help of the extensions of Euler's and Kummer's classical transformations. As special cases, we have recovered several results due to Sharma. The results established in this paper are simple, interesting, easily obtainable and may be useful.

  7. Elliptic hypergeometric integrals and 't Hooft anomaly matching conditions

    International Nuclear Information System (INIS)

    Spiridonov, V.P.; Vartanov, G.S.

    2012-03-01

    Elliptic hypergeometric integrals describe superconformal indices of 4d supersymmetric field theories. We show that all 't Hooft anomaly matching conditions for Seiberg dual theories can be derived from SL(3, Z)-modular transformation properties of the kernels of dual indices.

  8. Vortex beam characterization in terms of Hypergeometric- Gaussian modes

    CSIR Research Space (South Africa)

    Sephton, Bereneice C

    2016-10-01

    Full Text Available in Optics: The 100th OSA Annual Meeting and Exhibit/Laser Science XXXII , 17-21 October 2016, Rochester Riverside Convention Center, Rochester, New York United States Vortex beam characterization in terms of Hypergeometric- Gaussian modes Sephton...

  9. Hypergeometric continuation of divergent perturbation series: I. Critical exponents of the Bose–Hubbard model

    International Nuclear Information System (INIS)

    Sanders, Sören; Holthaus, Martin

    2017-01-01

    We study the connection between the exponent of the order parameter of the Mott insulator-to-superfluid transition occurring in the two-dimensional Bose–Hubbard model, and the divergence exponents of its one- and two-particle correlation functions. We find that at the multicritical points all divergence exponents are related to each other, allowing us to express the critical exponent in terms of one single divergence exponent. This approach correctly reproduces the critical exponent of the three-dimensional XY universality class. Because divergence exponents can be computed in an efficient manner by hypergeometric analytic continuation, our strategy is applicable to a wide class of systems. (paper)

  10. Hypergeometric continuation of divergent perturbation series: I. Critical exponents of the Bose-Hubbard model

    Science.gov (United States)

    Sanders, Sören; Holthaus, Martin

    2017-10-01

    We study the connection between the exponent of the order parameter of the Mott insulator-to-superfluid transition occurring in the two-dimensional Bose-Hubbard model, and the divergence exponents of its one- and two-particle correlation functions. We find that at the multicritical points all divergence exponents are related to each other, allowing us to express the critical exponent in terms of one single divergence exponent. This approach correctly reproduces the critical exponent of the three-dimensional XY universality class. Because divergence exponents can be computed in an efficient manner by hypergeometric analytic continuation, our strategy is applicable to a wide class of systems.

  11. Sampling Methods for Wallenius' and Fisher's Noncentral Hypergeometric Distributions

    DEFF Research Database (Denmark)

    Fog, Agner

    2008-01-01

    the mode, ratio-of-uniforms rejection method, and rejection by sampling in the tau domain. Methods for the multivariate distributions include: simulation of urn experiments, conditional method, Gibbs sampling, and Metropolis-Hastings sampling. These methods are useful for Monte Carlo simulation of models...... of biased sampling and models of evolution and for calculating moments and quantiles of the distributions.......Several methods for generating variates with univariate and multivariate Wallenius' and Fisher's noncentral hypergeometric distributions are developed. Methods for the univariate distributions include: simulation of urn experiments, inversion by binary search, inversion by chop-down search from...

  12. Propagation of hypergeometric Gaussian beams in strongly nonlocal nonlinear media

    Science.gov (United States)

    Tang, Bin; Bian, Lirong; Zhou, Xin; Chen, Kai

    2018-01-01

    Optical vortex beams have attracted lots of interest due to its potential application in image processing, optical trapping and optical communications, etc. In this work, we theoretically and numerically investigated the propagation properties of hypergeometric Gaussian (HyGG) beams in strongly nonlocal nonlinear media. Based on the Snyder-Mitchell model, analytical expressions for propagation of the HyGG beams in strongly nonlocal nonlinear media were obtained. The influence of input power and optical parameters on the evolutions of the beam width and radius of curvature is illustrated, respectively. The results show that the beam width and radius of curvature of the HyGG beams remain invariant, like a soliton when the input power is equal to the critical power. Otherwise, it varies periodically like a breather, which is the result of competition between the beam diffraction and nonlinearity of the medium.

  13. Hypergeometric Series Solution to a Class of Second-Order Boundary Value Problems via Laplace Transform with Applications to Nanofluids

    Science.gov (United States)

    Ebaid, Abdelhalim; Wazwaz, Abdul-Majid; Alali, Elham; Masaedeh, Basem S.

    2017-03-01

    Very recently, it was observed that the temperature of nanofluids is finally governed by second-order ordinary differential equations with variable coefficients of exponential orders. Such coefficients were then transformed to polynomials type by using new independent variables. In this paper, a class of second-order ordinary differential equations with variable coefficients of polynomials type has been solved analytically. The analytical solution is expressed in terms of a hypergeometric function with generalized parameters. Moreover, applications of the present results have been applied on some selected nanofluids problems in the literature. The exact solutions in the literature were derived as special cases of our generalized analytical solution.

  14. Factorization method for difference equations of hypergeometric type on nonuniform lattices

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez-Nodarse, R. [Departamento de Analisis Matematico, Universidad de Sevilla, Sevilla (Spain); Instituto Carlos I de Fisica Teorica y Computacional, Universidad de Granada, Granada (Spain); Costas-Santos, R.S. [Departamento de Analisis Matematico, Universidad de Sevilla, Sevilla (Spain)

    2001-07-13

    We study the factorization of the hypergeometric-type difference equation of Nikiforov and Uvarov on nonuniform lattices. An explicit form of the raising and lowering operators is derived and some relevant examples are given. (author)

  15. Special functions & their applications

    CERN Document Server

    Lebedev, N N

    1972-01-01

    Famous Russian work discusses the application of cylinder functions and spherical harmonics; gamma function; probability integral and related functions; Airy functions; hyper-geometric functions; more. Translated by Richard Silverman.

  16. Contractions of 2D 2nd Order Quantum Superintegrable Systems and the Askey Scheme for Hypergeometric Orthogonal Polynomials

    Directory of Open Access Journals (Sweden)

    Ernest G. Kalnins

    2013-10-01

    Full Text Available We show explicitly that all 2nd order superintegrable systems in 2 dimensions are limiting cases of a single system: the generic 3-parameter potential on the 2-sphere, S9 in our listing. We extend the Wigner-Inönü method of Lie algebra contractions to contractions of quadratic algebras and show that all of the quadratic symmetry algebras of these systems are contractions of that of S9. Amazingly, all of the relevant contractions of these superintegrable systems on flat space and the sphere are uniquely induced by the well known Lie algebra contractions of e(2 and so(3. By contracting function space realizations of irreducible representations of the S9 algebra (which give the structure equations for Racah/Wilson polynomials to the other superintegrable systems, and using Wigner's idea of ''saving'' a representation, we obtain the full Askey scheme of hypergeometric orthogonal polynomials. This relationship directly ties the polynomials and their structure equations to physical phenomena. It is more general because it applies to all special functions that arise from these systems via separation of variables, not just those of hypergeometric type, and it extends to higher dimensions.

  17. Confluent hypergeometric orthogonal polynomials related to the rational quantum Calogero system with harmonic confinement

    International Nuclear Information System (INIS)

    van Diejen, J.F.

    1997-01-01

    Two families (type A and type B) of confluent hypergeometric polynomials in several variables are studied. We describe the orthogonality properties, differential equations, and Pieri-type recurrence formulas for these families. In the one-variable case, the polynomials in question reduce to the Hermite polynomials (type A) and the Laguerre polynomials (type B), respectively. The multivariable confluent hypergeometric families considered here may be used to diagonalize the rational quantum Calogero models with harmonic confinement (for the classical root systems) and are closely connected to the (symmetric) generalized spherical harmonics investigated by Dunkl. (orig.)

  18. Elliptic hypergeometric integrals and 't Hooft anomaly matching conditions

    Energy Technology Data Exchange (ETDEWEB)

    Spiridonov, V.P. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Vartanov, G.S. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2012-05-15

    Elliptic hypergeometric integrals describe superconformal indices of 4d supersymmetric field theories. We show that all 't Hooft anomaly matching conditions for Seiberg dual theories can be derived from SL(3, Z)-modular transformation properties of the kernels of dual indices.

  19. Alien derivatives of the WKB solutions of the Gauss hypergeometric differential equation with a large parameter

    Directory of Open Access Journals (Sweden)

    Mika Tanda

    2015-01-01

    Full Text Available We compute alien derivatives of the WKB solutions of the Gauss hypergeometric differential equation with a large parameter and discuss the singularity structures of the Borel transforms of the WKB solution expressed in terms of its alien derivatives.

  20. A scan statistic for binary outcome based on hypergeometric probability model, with an application to detecting spatial clusters of Japanese encephalitis.

    Science.gov (United States)

    Zhao, Xing; Zhou, Xiao-Hua; Feng, Zijian; Guo, Pengfei; He, Hongyan; Zhang, Tao; Duan, Lei; Li, Xiaosong

    2013-01-01

    As a useful tool for geographical cluster detection of events, the spatial scan statistic is widely applied in many fields and plays an increasingly important role. The classic version of the spatial scan statistic for the binary outcome is developed by Kulldorff, based on the Bernoulli or the Poisson probability model. In this paper, we apply the Hypergeometric probability model to construct the likelihood function under the null hypothesis. Compared with existing methods, the likelihood function under the null hypothesis is an alternative and indirect method to identify the potential cluster, and the test statistic is the extreme value of the likelihood function. Similar with Kulldorff's methods, we adopt Monte Carlo test for the test of significance. Both methods are applied for detecting spatial clusters of Japanese encephalitis in Sichuan province, China, in 2009, and the detected clusters are identical. Through a simulation to independent benchmark data, it is indicated that the test statistic based on the Hypergeometric model outweighs Kulldorff's statistics for clusters of high population density or large size; otherwise Kulldorff's statistics are superior.

  1. The chiral Gaussian two-matrix ensemble of real asymmetric matrices

    International Nuclear Information System (INIS)

    Akemann, G; Phillips, M J; Sommers, H-J

    2010-01-01

    We solve a family of Gaussian two-matrix models with rectangular N x (N + ν) matrices, having real asymmetric matrix elements and depending on a non-Hermiticity parameter μ. Our model can be thought of as the chiral extension of the real Ginibre ensemble, relevant for Dirac operators in the same symmetry class. It has the property that its eigenvalues are either real, purely imaginary or come in complex conjugate eigenvalue pairs. The eigenvalue joint probability distribution for our model is explicitly computed, leading to a non-Gaussian distribution including K-Bessel functions. All n-point density correlation functions are expressed for finite N in terms of a Pfaffian form. This contains a kernel involving Laguerre polynomials in the complex plane as a building block which was previously computed by the authors. This kernel can be expressed in terms of the kernel for complex non-Hermitian matrices, generalizing the known relation among ensembles of Hermitian random matrices. Compact expressions are given for the density at finite N as an example, as well as its microscopic large-N limits at the origin for fixed ν at strong and weak non-Hermiticity.

  2. Factorization of the hypergeometric-type difference equation on non-uniform lattices: dynamical algebra

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez-Nodarse, R [Departamento de Analisis Matematico, Universidad de Sevilla, Apdo. 1160, E-41080 Sevilla (Spain); Atakishiyev, N M [Instituto de Matematicas, UNAM, Apartado Postal 273-3, CP 62210 Cuernavaca, Morelos, Mexico (Germany); Costas-Santos, R S [Departamento de Matematicas, EPS, Universidad Carlos III de Madrid, Ave. Universidad 30, E-28911, Leganes, Madrid (Spain)

    2005-01-07

    We argue that one can factorize the difference equation of hypergeometric type on non-uniform lattices in the general case. It is shown that in the most cases of q-linear spectrum of the eigenvalues, this directly leads to the dynamical symmetry algebra su{sub q}(1, 1), whose generators are explicitly constructed in terms of the difference operators, obtained in the process of factorization. Thus all models with the q-linear spectrum (some of them, but not all, previously considered in a number of publications) can be treated in a unified form.

  3. Symmetries of some hypergeometric series: Implications for 3j- and 6j-coefficients

    International Nuclear Information System (INIS)

    Louck, J.D.; Beyer, W.A.; Biedenharn, L.C.; Stein, P.R.

    1986-10-01

    The occurrence of generalized hypergeometric series as factors, in the Wigner-Clebsch-Gordan (3j) and Racah (6j) coefficients is well known. The recently discovered S 5 symmetry of the Saalscheutzian 4 F 3 series may be used to extend the symmetries of the 6j-coefficients to the much larger group generated by S 5 and the group of Regge symmetries. (A similar extension may be carried out for the 3j-coefficients). The required extension of the domain of definition of the 6j-coefficients and the properties of its symmetry group is developed here. 7 refs

  4. The O(αs3) massive operator matrix elements of O(nf) for the structure function F2(x,Q2) and transversity

    International Nuclear Information System (INIS)

    Ablinger, J.; Bluemlein, J.; Klein, S.; Schneider, C.; Wissbrock, F.

    2011-01-01

    The contributions ∝n f to the O(α s 3 ) massive operator matrix elements describing the heavy flavor Wilson coefficients in the limit Q 2 >>m 2 are computed for the structure function F 2 (x,Q 2 ) and transversity for general values of the Mellin variable N. Here, for two matrix elements, A qq,Q PS (N) and A qg,Q (N), the complete result is obtained. A first independent computation of the contributions to the 3-loop anomalous dimensions γ qg (N), γ qq PS (N), and γ qq NS,(TR) (N) is given. In the computation advanced summation technologies for nested sums over products of hypergeometric terms with harmonic sums have been used. For intermediary results generalized harmonic sums occur, while the final results can be expressed by nested harmonic sums only.

  5. Fractional Vector Calculus and Fractional Special Function

    OpenAIRE

    Li, Ming-Fan; Ren, Ji-Rong; Zhu, Tao

    2010-01-01

    Fractional vector calculus is discussed in the spherical coordinate framework. A variation of the Legendre equation and fractional Bessel equation are solved by series expansion and numerically. Finally, we generalize the hypergeometric functions.

  6. Acceptance sampling for attributes via hypothesis testing and the hypergeometric distribution

    Science.gov (United States)

    Samohyl, Robert Wayne

    2017-10-01

    This paper questions some aspects of attribute acceptance sampling in light of the original concepts of hypothesis testing from Neyman and Pearson (NP). Attribute acceptance sampling in industry, as developed by Dodge and Romig (DR), generally follows the international standards of ISO 2859, and similarly the Brazilian standards NBR 5425 to NBR 5427 and the United States Standards ANSI/ASQC Z1.4. The paper evaluates and extends the area of acceptance sampling in two directions. First, by suggesting the use of the hypergeometric distribution to calculate the parameters of sampling plans avoiding the unnecessary use of approximations such as the binomial or Poisson distributions. We show that, under usual conditions, discrepancies can be large. The conclusion is that the hypergeometric distribution, ubiquitously available in commonly used software, is more appropriate than other distributions for acceptance sampling. Second, and more importantly, we elaborate the theory of acceptance sampling in terms of hypothesis testing rigorously following the original concepts of NP. By offering a common theoretical structure, hypothesis testing from NP can produce a better understanding of applications even beyond the usual areas of industry and commerce such as public health and political polling. With the new procedures, both sample size and sample error can be reduced. What is unclear in traditional acceptance sampling is the necessity of linking the acceptable quality limit (AQL) exclusively to the producer and the lot quality percent defective (LTPD) exclusively to the consumer. In reality, the consumer should also be preoccupied with a value of AQL, as should the producer with LTPD. Furthermore, we can also question why type I error is always uniquely associated with the producer as producer risk, and likewise, the same question arises with consumer risk which is necessarily associated with type II error. The resolution of these questions is new to the literature. The

  7. Scattering of long folded strings and mixed correlators in the two-matrix model

    International Nuclear Information System (INIS)

    Bourgine, J.-E.; Hosomichi, K.; Kostov, I.; Matsuo, Y.

    2008-01-01

    We study the interactions of Maldacena's long folded strings in two-dimensional string theory. We find the amplitude for a state containing two long folded strings to come and go back to infinity. We calculate this amplitude both in the worldsheet theory and in the dual matrix model, the matrix quantum mechanics. The matrix model description allows to evaluate the amplitudes involving any number of long strings, which are given by the mixed trace correlators in an effective two-matrix model

  8. Group theoretical basis of some identities for the generalized hypergeometric series

    International Nuclear Information System (INIS)

    Beyer, W.A.; Louck, J.D.; Stein, P.R.

    1987-01-01

    It is shown that Thomae's identity between two 3 F 2 hypergeometric series of unit argument together with the trivial invariance under separate permutations of numerator and denominator parameters implies that the symmetric group S 5 is an invariance group of this series. A similar result is proved for the terminating Saalschuetzian 4 F 3 series, where S 6 is shown to be the invariance group of this series (or S 5 if one parameter is eliminated by using the Saalschuetz condition). Here Bailey's identity is realized as a permutation of appropriately defined parameters. Finally, the set of three-term relations between 3 F 2 series of unit argument discovered by Thomae [J. Thomae, J. Reine Angew. Math. 87, 26 (1879)] and systematized by Whipple [F. J. Whipple, Proc. London Math. Soc. 23, 104 (1925)] is shown to be transformed into itself under the action of the group S 6 x Λ, where Λ is a two-element group. The 12 left cosets of S 6 x Λ with respect to the invariance group S 5 are the structural elements underlying the three-term relations. The symbol manipulator macsyma was used to obtain preliminary results

  9. A bispectral q-hypergeometric basis for a class of quantum integrable models

    Science.gov (United States)

    Baseilhac, Pascal; Martin, Xavier

    2018-01-01

    For the class of quantum integrable models generated from the q-Onsager algebra, a basis of bispectral multivariable q-orthogonal polynomials is exhibited. In the first part, it is shown that the multivariable Askey-Wilson polynomials with N variables and N + 3 parameters introduced by Gasper and Rahman [Dev. Math. 13, 209 (2005)] generate a family of infinite dimensional modules for the q-Onsager algebra, whose fundamental generators are realized in terms of the multivariable q-difference and difference operators proposed by Iliev [Trans. Am. Math. Soc. 363, 1577 (2011)]. Raising and lowering operators extending those of Sahi [SIGMA 3, 002 (2007)] are also constructed. In the second part, finite dimensional modules are constructed and studied for a certain class of parameters and if the N variables belong to a discrete support. In this case, the bispectral property finds a natural interpretation within the framework of tridiagonal pairs. In the third part, eigenfunctions of the q-Dolan-Grady hierarchy are considered in the polynomial basis. In particular, invariant subspaces are identified for certain conditions generalizing Nepomechie's relations. In the fourth part, the analysis is extended to the special case q = 1. This framework provides a q-hypergeometric formulation of quantum integrable models such as the open XXZ spin chain with generic integrable boundary conditions (q ≠ 1).

  10. Loop equations and topological recursion for the arbitrary-$\\beta$ two-matrix model

    CERN Document Server

    Bergère, Michel; Marchal, Olivier; Prats-Ferrer, Aleix

    2012-01-01

    We write the loop equations for the $\\beta$ two-matrix model, and we propose a topological recursion algorithm to solve them, order by order in a small parameter. We find that to leading order, the spectral curve is a "quantum" spectral curve, i.e. it is given by a differential operator (instead of an algebraic equation for the hermitian case). Here, we study the case where that quantum spectral curve is completely degenerate, it satisfies a Bethe ansatz, and the spectral curve is the Baxter TQ relation.

  11. Singular value correlation functions for products of Wishart random matrices

    International Nuclear Information System (INIS)

    Akemann, Gernot; Kieburg, Mario; Wei, Lu

    2013-01-01

    We consider the product of M quadratic random matrices with complex elements and no further symmetry, where all matrix elements of each factor have a Gaussian distribution. This generalizes the classical Wishart–Laguerre Gaussian unitary ensemble with M = 1. In this paper, we first compute the joint probability distribution for the singular values of the product matrix when the matrix size N and the number M are fixed but arbitrary. This leads to a determinantal point process which can be realized in two different ways. First, it can be written as a one-matrix singular value model with a non-standard Jacobian, or second, for M ⩾ 2, as a two-matrix singular value model with a set of auxiliary singular values and a weight proportional to the Meijer G-function. For both formulations, we determine all singular value correlation functions in terms of the kernels of biorthogonal polynomials which we explicitly construct. They are given in terms of the hypergeometric and Meijer G-functions, generalizing the Laguerre polynomials for M = 1. Our investigation was motivated from applications in telecommunication of multi-layered scattering multiple-input and multiple-output channels. We present the ergodic mutual information for finite-N for such a channel model with M − 1 layers of scatterers as an example. (paper)

  12. Functional equation for the Mordell-Tornheim multiple zeta-function

    OpenAIRE

    Okamoto, Takuya; Onozuka, Tomokazu

    2016-01-01

    We show a relation between the Mordell-Tornheim multiple zeta-function and the confluent hypergeometric function, and using it, we give the functional equation for the Mordell-Tornheim multiple zeta-function. In the double case, the functional equation includes the known functional equation for the Euler-Zagier double zeta-function.

  13. The theory of contractions of 2D 2nd order quantum superintegrable systems and its relation to the Askey scheme for hypergeometric orthogonal polynomials

    International Nuclear Information System (INIS)

    Miller, Willard Jr

    2014-01-01

    We describe a contraction theory for 2nd order superintegrable systems, showing that all such systems in 2 dimensions are limiting cases of a single system: the generic 3-parameter potential on the 2-sphere, S9 in our listing. Analogously, all of the quadratic symmetry algebras of these systems can be obtained by a sequence of contractions starting from S9. By contracting function space realizations of irreducible representations of the S9 algebra (which give the structure equations for Racah/Wilson polynomials) to the other superintegrable systems one obtains the full Askey scheme of orthogonal hypergeometric polynomials.This relates the scheme directly to explicitly solvable quantum mechanical systems. Amazingly, all of these contractions of superintegrable systems with potential are uniquely induced by Wigner Lie algebra contractions of so(3, C) and e(2, C). The present paper concentrates on describing this intimate link between Lie algebra and superintegrable system contractions, with the detailed calculations presented elsewhere. Joint work with E. Kalnins, S. Post, E. Subag and R. Heinonen.

  14. Spectral transformation chains and some new biorthogonal rational functions

    International Nuclear Information System (INIS)

    Spiridonov, V.

    2000-01-01

    A discrete-time chain, associated with the generalized eigenvalue problem for two Jacobi matrices, is derived. Various discrete and continuous symmetries of this integrable equation are revealed. A class of its rational, elementary and elliptic function solutions, appearing from a similarity reduction, are constructed. The latter lead to large families of biorthogonal rational functions based upon the very-well-posed balanced hypergeometric series of three types: the standard hypergeometric series 9 F 8 , basic series 10 φ 9 and its elliptic analogue 10 E 9 . For an important subclass of the elliptic biorthogonal rational functions the weight function and normalization constants are determined explicitly. (orig.)

  15. Generalized Mittag-Leffler Function and Its Properties

    Directory of Open Access Journals (Sweden)

    Banu Yılmaz Yaşar

    2014-12-01

    Full Text Available Recently, Srivastava, Çetinkaya and Kıymaz defined the generalized Pochhammer symbol and obtained some relations. In this paper, we define the generalized Mittag-Leffler function via the generalized Pochhammer symbol and present some recurrence relation, derivative properties, integral representation. Moreover, we obtain a relation between Wright hypergeometric function and the generalized Mittag-Leffler function.

  16. Asymptotics and Numerics of Polynomials Used in Tricomi and Buchholz Expansions of Kummer functions

    NARCIS (Netherlands)

    J.L. López; N.M. Temme (Nico)

    2010-01-01

    textabstractExpansions in terms of Bessel functions are considered of the Kummer function ${}_1F_1(a;c,z)$ (or confluent hypergeometric function) as given by Tricomi and Buchholz. The coefficients of these expansions are polynomials in the parameters of the Kummer function and the asymptotic

  17. Solution of degenerate hypergeometric system of Horn consisting of three equations

    Science.gov (United States)

    Tasmambetov, Zhaksylyk N.; Zhakhina, Ryskul U.

    2017-09-01

    The possibilities of constructing normal-regular solutions of a system consisting of three partial differential equations of the second order are studied by the Frobenius-Latysheva method. The method of determining unknown coefficients is shown and the relationship of the studied system with the system, which solution is Laguerre's polynomial of three variables is indicated. The generalization of the Frobenius-Latysheva method to the case of a system consisting of three equations makes it possible to clarify the relationship of such systems, which solutions are special functions of three variables. These systems include the functions of Whittaker and Bessel, 205 special functions of three variables from the list of M. Srivastava and P.W. Carlsson, as well as orthogonal polynomials of three variables. All this contributes to the further development of the analytic theory of systems consisting of three partial differential equations of the second order.

  18. Special functions for scientists and engineers

    CERN Document Server

    Bell, William Wallace

    1968-01-01

    Clear and comprehensive, this text provides undergraduates with a straightforward guide to special functions. It is equally suitable as a reference volume for professionals, and readers need no higher level of mathematical knowledge beyond elementary calculus. Topics include the solution of second-order differential equations in terms of power series; gamma and beta functions; Legendre polynomials and functions; Bessel functions; Hermite, Laguerre, and Chebyshev polynomials; Gegenbauer and Jacobi polynomials; and hypergeometric and other special functions. Three appendices offer convenient t

  19. Appell functions and the scalar one-loop three-point integrals in Feynman diagrams

    Energy Technology Data Exchange (ETDEWEB)

    Cabral-Rosetti, L G [Departamento de Posgrado, Centro Interdisciplinario de Investigacion y Docencia en Educacion Tecnica (CIIDET), Av. Universidad 282 Pte., Col. Centro, A. Postal 752, C.P. 76000, Santiago de Queretaro, Qro. (Mexico); Sanchis-Lozano, M A [Departamento de Fisica Teorica and IFIC, Centro Mixto Universidad de Valencia-CSIC, 46100 Burjassot, Valencia (Spain)

    2006-05-15

    The scalar three-point function appearing in one-loop Feynman diagrams is compactly expressed in terms of a generalized hypergeometric function of two variables. Use is made of the connection between such Appell function and dilogarithms coming from a previous investigation. Special cases are obtained for particular values of internal masses and external momenta.

  20. Closed-Form Representations of the Density Function and Integer Moments of the Sample Correlation Coefficient

    Directory of Open Access Journals (Sweden)

    Serge B. Provost

    2015-07-01

    Full Text Available This paper provides a simplified representation of the exact density function of R, the sample correlation coefficient. The odd and even moments of R are also obtained in closed forms. Being expressed in terms of generalized hypergeometric functions, the resulting representations are readily computable. Some numerical examples corroborate the validity of the results derived herein.

  1. Genus one super-Green function revisited and superstring amplitudes with non-maximal supersymmetry

    International Nuclear Information System (INIS)

    Itoyama, H.; Yano, Kohei

    2016-01-01

    We reexamine genus one super-Green functions with general boundary conditions twisted by (α,β) for (σ,τ) directions in the eigenmode expansion and derive expressions as infinite series of hypergeometric functions. Using these, we compute one-loop superstring amplitudes with non-maximal supersymmetry, taking the example of massless vector emissions of open string type I Z 2 orbifold

  2. Degenerate T coefficients and their relation to Wigner's 3j symbols and the D function

    International Nuclear Information System (INIS)

    Kuznetsov, G.I.; Smorodinskij, Ya.A.

    1977-01-01

    On basis of various representations of the T coefficients and using limiting procedures, var//uios degenerate cases are studied for these coefficients and their relation This enables one to find relations between the hypergeometric function 4 F 3 (....1) and the functions 3 F 2 (...1) and 2 F 1 (...1/2)

  3. Marichev-Saigo-Maeda fractional integration operators of the Bassel functions

    Directory of Open Access Journals (Sweden)

    Sunil D. Purohit

    2012-05-01

    Full Text Available In this paper, we apply generalized operators of fractional integration involving Appell’s function F_3 (. due to Marichev-Saigo-Maeda, to the Bessel function of first kind. The results are expressed in terms of generalized Wright function and hypergeometric functions _pF_q . Special cases involving this function are mentioned. Results given recently by Kilbas and Sebastian follow as special cases of the theorems establish here.

  4. Species identification of clinical isolates of anaerobic bacteria: a comparison of two matrix-assisted laser desorption ionization-time of flight mass spectrometry systems

    DEFF Research Database (Denmark)

    Justesen, Ulrik Stenz; Holm, Anette; Knudsen, Elisa

    2011-01-01

    We compared two matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) systems (Shimadzu/SARAMIS and Bruker) on a collection of consecutive clinically important anaerobic bacteria (n = 290). The Bruker system had more correct identifications to the species level...... (67.2% versus 49.0%), but also more incorrect identifications (7.9% versus 1.4%). The system databases need to be optimized to increase identification levels. However, MALDI-TOF MS in its present version seems to be a fast and inexpensive method for identification of most clinically important...

  5. Unified Bessel, Modified Bessel, Spherical Bessel and Bessel-Clifford Functions

    OpenAIRE

    Yaşar, Banu Yılmaz; Özarslan, Mehmet Ali

    2016-01-01

    In the present paper, unification of Bessel, modified Bessel, spherical Bessel and Bessel-Clifford functions via the generalized Pochhammer symbol [ Srivastava HM, Cetinkaya A, K{\\i}ymaz O. A certain generalized Pochhammer symbol and its applications to hypergeometric functions. Applied Mathematics and Computation, 2014, 226 : 484-491] is defined. Several potentially useful properties of the unified family such as generating function, integral representation, Laplace transform and Mellin tran...

  6. Three-level models solvable in terms of the Clausen function

    Energy Technology Data Exchange (ETDEWEB)

    Ishkhanyan, Artur [Engineering Center of Armenian National Academy of Sciences, Ashtarak-2, 378410 (Armenia); Suominen, Kalle-Antti [Helsinki Institute of Physics, PL 64, FIN-00014 Helsingin yliopisto (Finland)

    2003-07-04

    The problem of analytical integrability of the three-level problem by reduction of the time-dependent Schroedinger equations to the third-order linear differential equation satisfied by the generalized hypergeometric functions {sub 3}F{sub 2} is considered. A total of 12 infinite classes of models solvable in terms of these functions is found, most of which are new and others are generalizations of the previously known families.

  7. Three-level models solvable in terms of the Clausen function

    International Nuclear Information System (INIS)

    Ishkhanyan, Artur; Suominen, Kalle-Antti

    2003-01-01

    The problem of analytical integrability of the three-level problem by reduction of the time-dependent Schroedinger equations to the third-order linear differential equation satisfied by the generalized hypergeometric functions 3 F 2 is considered. A total of 12 infinite classes of models solvable in terms of these functions is found, most of which are new and others are generalizations of the previously known families

  8. Some Connections between the Spherical and Parabolic Bases on the Cone Expressed in terms of the Macdonald Function

    OpenAIRE

    Shilin, I. A.; Choi, Junesang

    2014-01-01

    Computing the matrix elements of the linear operator, which transforms the spherical basis of $SO(3,1)$ -representation space into the hyperbolic basis, very recently, Shilin and Choi (2013) presented an integral formula involving the product of two Legendre functions of the first kind expressed in terms of ${ }_{4}{F}_{3}$ -hypergeometric function and, using the general Mehler-Fock transform, another integral formula for the Legendre function of the first kind. In the sequel, we investigate ...

  9. Hermite-Hadamard Type Integral Inequalities for Functions Whose Second-Order Mixed Derivatives Are Coordinated (s,m-P-Convex

    Directory of Open Access Journals (Sweden)

    Yu-Mei Bai

    2018-01-01

    Full Text Available We establish some new Hermite-Hadamard type integral inequalities for functions whose second-order mixed derivatives are coordinated (s,m-P-convex. An expression form of Hermite-Hadamard type integral inequalities via the beta function and the hypergeometric function is also presented. Our results provide a significant complement to the work of Wu et al. involving the Hermite-Hadamard type inequalities for coordinated (s,m-P-convex functions in an earlier article.

  10. Inequalities for the Modified k-Bessel Function

    Directory of Open Access Journals (Sweden)

    Saiful Rahman Mondal

    2017-07-01

    Full Text Available The article considers the generalized k-Bessel functions and represents it as Wright functions. Then we study the monotonicity properties of the ratio of two different orders k- Bessel functions, and the ratio of the k-Bessel and the k-Bessel functions. The log-convexity with respect to the order of the k-Bessel also given. An investigation regarding the monotonicity of the ratio of the k-Bessel and k-confluent hypergeometric functions are discussed.

  11. Green function of the model two-centre quantum-mechanical problem

    International Nuclear Information System (INIS)

    Khoma, M.V.; Lazur, V.Yu.

    2002-01-01

    The expansions of a Green function for the Simmons molecular potential (SMP) in terms of spheroidal function are built. The solutions of degenerate hypergeometric equation are used as basis function system while expanding regular and irregular model spheroidal functions into series. Rather simple three-terms recurrence relations are obtained for the coefficients of these expansions. Much attentions is given to different asymptotic representation as well as Sturmian expansions of the Green function of the two-centre SMP wave functions. In all cases considered the Green function is reduced to the form similar to the Hostler's representation of the Coulomb Green function

  12. Luigi Gatteschi's work on asymptotics of special functions and their zeros

    Science.gov (United States)

    Gautschi, Walter; Giordano, Carla

    2008-12-01

    A good portion of Gatteschi's research publications-about 65%-is devoted to asymptotics of special functions and their zeros. Most prominently among the special functions studied figure classical orthogonal polynomials, notably Jacobi polynomials and their special cases, Laguerre polynomials, and Hermite polynomials by implication. Other important classes of special functions dealt with are Bessel functions of the first and second kind, Airy functions, and confluent hypergeometric functions, both in Tricomi's and Whittaker's form. This work is reviewed here, and organized along methodological lines.

  13. Revised Line Profile Function for Hydrogenic Species

    Directory of Open Access Journals (Sweden)

    Sapar A.

    2012-09-01

    Full Text Available Analytical series expansions for the hydrogenic spectral line profile functions are derived starting from the three single expressions, obtained by integrating twice the convolution of the Holtsmark, Lorentz and Doppler line profile functions. We get well converging series expansions for the line wings and centers by reducing the number of arguments in the profile function by one, introducing the module of the Holtsmark and Lorentz profiles as a new argument. In the intermediate part of the line, the parabolic cylinder functions expressed via the confluent hypergeometric series, are used. The multi-component Stark splitting of the hydrogenic spectral lines and the modeled stochastic electron transitions in the electric field of the adjacent ions generate wide Doppler plateaux at the line centers, with the characteristic widths estimated from the fit to the characteristic width of the Holtsmark profile. This additional Doppler broadening of the line profile function removes the central dip typical to the Holtsmark profile.

  14. Scalar one-loop vertex integrals as meromorphic functions of space-time dimension d

    International Nuclear Information System (INIS)

    Bluemlein, Johannes; Phan, Khiem Hong; Vietnam National Univ., Ho Chi Minh City; Riemann, Tord; Silesia Univ., Chorzow

    2017-11-01

    Representations are derived for the basic scalar one-loop vertex Feynman integrals as meromorphic functions of the space-time dimension d in terms of (generalized) hypergeometric functions 2 F 1 and F 1 . Values at asymptotic or exceptional kinematic points as well as expansions around the singular points at d=4+2n, n non-negative integers, may be derived from the representations easily. The Feynman integrals studied here may be used as building blocks for the calculation of one-loop and higher-loop scalar and tensor amplitudes. From the recursion relation presented, higher n-point functions may be obtained in a straightforward manner.

  15. Some Families of the Incomplete H-Functions and the Incomplete \\overline H -Functions and Associated Integral Transforms and Operators of Fractional Calculus with Applications

    Science.gov (United States)

    Srivastava, H. M.; Saxena, R. K.; Parmar, R. K.

    2018-01-01

    Our present investigation is inspired by the recent interesting extensions (by Srivastava et al. [35]) of a pair of the Mellin-Barnes type contour integral representations of their incomplete generalized hypergeometric functions p γ q and p Γ q by means of the incomplete gamma functions γ( s, x) and Γ( s, x). Here, in this sequel, we introduce a family of the relatively more general incomplete H-functions γ p,q m,n ( z) and Γ p,q m,n ( z) as well as their such special cases as the incomplete Fox-Wright generalized hypergeometric functions p Ψ q (γ) [ z] and p Ψ q (Γ) [ z]. The main object of this paper is to study and investigate several interesting properties of these incomplete H-functions, including (for example) decomposition and reduction formulas, derivative formulas, various integral transforms, computational representations, and so on. We apply some substantially general Riemann-Liouville and Weyl type fractional integral operators to each of these incomplete H-functions. We indicate the easilyderivable extensions of the results presented here that hold for the corresponding incomplete \\overline H -functions as well. Potential applications of many of these incomplete special functions involving (for example) probability theory are also indicated.

  16. Conformal four point functions and the operator product expansion

    International Nuclear Information System (INIS)

    Dolan, F.A.; Osborn, H.

    2001-01-01

    Various aspects of the four point function for scalar fields in conformally invariant theories are analysed. This depends on an arbitrary function of two conformal invariants u,v. A recurrence relation for the function corresponding to the contribution of an arbitrary spin field in the operator product expansion to the four point function is derived. This is solved explicitly in two and four dimensions in terms of ordinary hypergeometric functions of variables z,x which are simply related to u,v. The operator product expansion analysis is applied to the explicit expressions for the four point function found for free scalar, fermion and vector field theories in four dimensions. The results for four point functions obtained by using the AdS/CFT correspondence are also analysed in terms of functions related to those appearing in the operator product discussion

  17. Generalized fractional integration of the \\overline{H}-function

    Directory of Open Access Journals (Sweden)

    Praveen Agarwal

    2012-11-01

    Full Text Available A significantly large number of earlier works on the subject of fractional calculus give interesting account of the theory and applications of fractional calculus operators in many different areas of mathematical analysis (such as ordinary and partial differential equations, integral equations, special functions, summation of series, et cetera. In the present paper, we study and develop the generalized fractional integral operators given by Saigo. First, we establish two Theorems that give the images of the product of H-function and a general class of polynomials inSaigo operators. On account of the general nature of the Saigo operators, H-function and a general class of polynomials a large number of new and known Images involving Riemann-Liouville and Erdélyi-Kober fractional integral operators and several special functions notably generalized Wright hypergeometric function, generalized Wright-Bessel function, the polylogarithm and Mittag-Leffler functions follow as special cases of our main findings.

  18. Higher-order automatic differentiation of mathematical functions

    Science.gov (United States)

    Charpentier, Isabelle; Dal Cappello, Claude

    2015-04-01

    Functions of mathematical physics such as the Bessel functions, the Chebyshev polynomials, the Gauss hypergeometric function and so forth, have practical applications in many scientific domains. On the one hand, differentiation formulas provided in reference books apply to real or complex variables. These do not account for the chain rule. On the other hand, based on the chain rule, the automatic differentiation has become a natural tool in numerical modeling. Nevertheless automatic differentiation tools do not deal with the numerous mathematical functions. This paper describes formulas and provides codes for the higher-order automatic differentiation of mathematical functions. The first method is based on Faà di Bruno's formula that generalizes the chain rule. The second one makes use of the second order differential equation they satisfy. Both methods are exemplified with the aforementioned functions.

  19. Special functions and the theory of group representations

    CERN Document Server

    Vilenkin, N Ja

    1968-01-01

    A standard scheme for a relation between special functions and group representation theory is the following: certain classes of special functions are interpreted as matrix elements of irreducible representations of a certain Lie group, and then properties of special functions are related to (and derived from) simple well-known facts of representation theory. The book combines the majority of known results in this direction. In particular, the author describes connections between the exponential functions and the additive group of real numbers (Fourier analysis), Legendre and Jacobi polynomials and representations of the group SU(2), and the hypergeometric function and representations of the group SL(2,R), as well as many other classes of special functions.

  20. Evaluation of integrals involving powers of (1-x2) and two associated Legendre functions or Gegenbauer polynomials

    International Nuclear Information System (INIS)

    Rashid, M.A.

    1984-08-01

    Integrals involving powers of (1-x 2 ) and two associated Legendre functions or two Gegenbauer polynomials are evaluated as finite sums which can be expressed in terms of terminating hypergeometric function 4 F 3 . The integrals which are evaluated are ∫sub(-1)sup(1)[Psub(l)sup(m)(x)Psub(k)sup(n)(x)]/[(1-x 2 )sup(p+1)]dx and ∫sub(-1)sup(1)Csub(l)sup(α)(x)Csub(k)sup(β)(x)[(1-x 2 )sup[(α+β-3)/2-p

  1. New formulae between Jacobi polynomials and some fractional Jacobi functions generalizing some connection formulae

    Science.gov (United States)

    Abd-Elhameed, W. M.

    2017-07-01

    In this paper, a new formula relating Jacobi polynomials of arbitrary parameters with the squares of certain fractional Jacobi functions is derived. The derived formula is expressed in terms of a certain terminating hypergeometric function of the type _4F3(1) . With the aid of some standard reduction formulae such as Pfaff-Saalschütz's and Watson's identities, the derived formula can be reduced in simple forms which are free of any hypergeometric functions for certain choices of the involved parameters of the Jacobi polynomials and the Jacobi functions. Some other simplified formulae are obtained via employing some computer algebra algorithms such as the algorithms of Zeilberger, Petkovsek and van Hoeij. Some connection formulae between some Jacobi polynomials are deduced. From these connection formulae, some other linearization formulae of Chebyshev polynomials are obtained. As an application to some of the introduced formulae, a numerical algorithm for solving nonlinear Riccati differential equation is presented and implemented by applying a suitable spectral method.

  2. Families of Meromorphic Multivalent Functions Associated with the Dziok-Raina Operator

    Directory of Open Access Journals (Sweden)

    G. Murugusundaramoorthy

    2013-07-01

    Full Text Available Making use a linear operator, which is defined here by means of the Hadamard product (or convolution, involving the Wright’s generalized hypergeometric function , we introduce two novel subclassesP p(q,s,α1;A,B,λ andP+p(q,s,α1;A,B,λ of meromorphically multivalent functions oforder λ(0 ≤ λ < p in the punctured disc U∗. In this paper we investigate the various important properties and characteristics of these subclasses of meromorphically multivalent functions. We extend the familiar concept of neighborhoods of analytic functions to these subclasses of meromorphically multivalent functions . We also derive many interesting results for the Hadamard products of functions belonging to the classP+p(q,s,α1;A,B,λ.

  3. Phase function of a spherical particle when scattering an inhomogeneous electromagnetic plane wave

    DEFF Research Database (Denmark)

    Frisvad, Jeppe Revall

    2018-01-01

    of the complex hypergeometric function 2F1 for every term of a series expansion. In this work, I develop a simpler solution based on associated Legendre functions with argument zero. It is similar to the solution for homogeneous plane waves but with new explicit expressions for the angular dependency of the far......In absorbing media, electromagnetic plane waves are most often inhomogeneous. Existing solutions for the scattering of an inhomogeneous plane wave by a spherical particle provide no explicit expressions for the scattering components. In addition, current analytical solutions require evaluation......-field scattering components, that is, the phase function. I include recurrence formulae for practical evaluation and provide numerical examples to evaluate how well the new expressions match previous work in some limiting cases. The predicted difference in the scattering phase function due to inhomogeneity...

  4. Scalar one-loop vertex integrals as meromorphic functions of space-time dimension d

    Energy Technology Data Exchange (ETDEWEB)

    Bluemlein, Johannes [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Phan, Khiem Hong [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Vietnam National Univ., Ho Chi Minh City (Viet Nam). Univ. of Science; Riemann, Tord [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Silesia Univ., Chorzow (Poland). Inst. of Physics

    2017-11-15

    Representations are derived for the basic scalar one-loop vertex Feynman integrals as meromorphic functions of the space-time dimension d in terms of (generalized) hypergeometric functions {sub 2}F{sub 1} and F{sub 1}. Values at asymptotic or exceptional kinematic points as well as expansions around the singular points at d=4+2n, n non-negative integers, may be derived from the representations easily. The Feynman integrals studied here may be used as building blocks for the calculation of one-loop and higher-loop scalar and tensor amplitudes. From the recursion relation presented, higher n-point functions may be obtained in a straightforward manner.

  5. HIGHLY PRECISE APPROXIMATION OF FREE SURFACE GREEN FUNCTION AND ITS HIGH ORDER DERIVATIVES BASED ON REFINED SUBDOMAINS

    Directory of Open Access Journals (Sweden)

    Jiameng Wu

    2018-01-01

    Full Text Available The infinite depth free surface Green function (GF and its high order derivatives for diffraction and radiation of water waves are considered. Especially second order derivatives are essential requirements in high-order panel method. In this paper, concerning the classical representation, composed of a semi-infinite integral involving a Bessel function and a Cauchy singularity, not only the GF and its first order derivatives but also second order derivatives are derived from four kinds of analytical series expansion and refined division of whole calculation domain. The approximations of special functions, particularly the hypergeometric function and the algorithmic applicability with different subdomains are implemented. As a result, the computation accuracy can reach 10-9 in whole domain compared with conventional methods based on direct numerical integration. Furthermore, numerical efficiency is almost equivalent to that with the classical method.

  6. Solutions of the two-level problem in terms of biconfluent Heun functions

    Energy Technology Data Exchange (ETDEWEB)

    Ishkhanyan, Artur [Engineering Center of Armenian National Academy of Sciences, Ashtarak (Armenia)]. E-mail: artur@ec.sci.am; Suominen, Kalle-Antti [Helsinki Institute of Physics, Helsinki (Finland); Department of Applied Physics, University of Turku, Turku (Finland)

    2001-08-17

    Five four-parametric classes of quantum mechanical two-level models permitting solutions in terms of the biconfluent Heun function are derived. Three of these classes are generalizations of the well known classes of Landau-Zener, Nikitin and Crothers. It is shown that two other classes describe super- and sublinear and essentially nonlinear level crossings, as well as processes with three crossing points. In particular, these classes include two-level models where the field amplitude is constant and the detuning varies as {delta}{sub 0}t+{delta}{sub 2}t{sup 3} or {approx}t{sup 1/3}. For the essentially nonlinear cubic-crossing model, {delta}{sub t}{approx}{delta}{sub 2}t{sup 3}, the general solution of the two-level problem is shown to be expressed as series of confluent hypergeometric functions. (author)

  7. Values of the polygamma functions at rational arguments

    International Nuclear Information System (INIS)

    Choi, Junesang; Cvijovic, Djurdje

    2007-01-01

    Gauss in 1812, in his celebrated memoir on the hypergeometric series, presented a remarkable formula for the psi (or digamma) function, ψ(z), at rational arguments z, which can be expressed in terms of elementary functions. Davis in 1935 extended Gauss's result to the polygamma functions ψ (n) (z) (n element of N) by using a known series representation of ψ (n) (z) in an elementary yet technical way. Koelbig in 1996, in his CERN technical report, also gave two extensions to ψ (n) (z) by using the series definition of polylogarithm function and the above-known series representation. Here we aim at deriving general formulae expressing ψ (n) (z) (n element of N 0 ) as rational arguments in terms of other functions, which will be obtained in two ways. In addition, several special cases are also considered and, as a by-product of our main results, we derive, in a simple and unified manner, all formulae given by Gauss, Davis and Koelbig. Finally, it should be noted that all our results, in view of the relationship between ψ (n) (z) and the Hurwitz zeta function, ζ(s, a), could be rewritten in the representation of ζ(s, a)

  8. Dirac Coulomb Green's function and its application to relativistic Rayleigh scattering

    International Nuclear Information System (INIS)

    Wong, M.K.F.; Yeh, E.H.Y.

    1985-01-01

    The Dirac Coulomb Green's function is obtained in both coordinate and momentum space. The Green's function in coordinate space is obtained by the eigenfunction expansion method in terms of the wave functions obtained by Wong and Yeh. The result is simpler than those obtained previously by other authors, in that the radial part for each component contains one term only instead of four terms. Our Green's function reduces to the Schroedinger Green's function upon some simple conditions, chiefly by neglecting the spin and replacing lambda by l. The Green's function in momentum space is obtained as the Fourier transform of the coordinate space Green's function, and is expressed in terms of basically three types of functions: (1) F/sub A/ (α; β 1 β 2 β 3 ; γ 1 γ 2 γ 3 ; z 1 z 2 z 3 ), (2) the hypergeometric function, and (3) spherical harmonics. The matrix element for Rayleigh scattering, or elastic Compton scattering, from relativistically bound electrons is then obtained in analytically closed form. The matrix element is written basically in terms of the coordinate space Dirac Coulomb Green's function. The technique used in the evaluation of the matrix element is based on the calculation of the momentum space Dirac Coulomb Green's function. Finally the relativistic result is compared with the nonrelativistic result

  9. Approximate Treatment of the Dirac Equation with Hyperbolic Potential Function

    Science.gov (United States)

    Durmus, Aysen

    2018-03-01

    The time independent Dirac equation is solved analytically for equal scalar and vector hyperbolic potential function in the presence of Greene and Aldrich approximation scheme. The bound state energy equation and spinor wave functions expressed by the hypergeometric function have been obtained in detail with asymptotic iteration approach. In order to indicate the accuracy of this different approach proposed to solve second order linear differential equations, we present that in the non-relativistic limit, analytical solutions of the Dirac equation converge to those of the Schrödinger one. We introduce numerical results of the theoretical analysis for hyperbolic potential function. Bound states corresponding to arbitrary values of n and l are reported for potential parameters covering a wide range of interaction. Also, we investigate relativistic vibrational energy spectra of alkali metal diatomic molecules in the different electronic states. It is observed that theoretical vibrational energy values are consistent with experimental Rydberg-Klein-Rees (RKR) results and vibrational energies of NaK, K_2 and KRb diatomic molecules interacting with hyperbolic potential smoothly converge to the experimental dissociation limit D_e=2508cm^{-1}, 254cm^{-1} and 4221cm^{-1}, respectively.

  10. Extended Riemann-Liouville type fractional derivative operator with applications

    Directory of Open Access Journals (Sweden)

    Agarwal P.

    2017-12-01

    Full Text Available The main purpose of this paper is to introduce a class of new extended forms of the beta function, Gauss hypergeometric function and Appell-Lauricella hypergeometric functions by means of the modified Bessel function of the third kind. Some typical generating relations for these extended hypergeometric functions are obtained by defining the extension of the Riemann-Liouville fractional derivative operator. Their connections with elementary functions and Fox’s H-function are also presented.

  11. Special functions of mathematical physics a unified introduction with applications

    CERN Document Server

    Nikiforov, Arnold F

    1988-01-01

    With students of Physics chiefly in mind, we have collected the material on special functions that is most important in mathematical physics and quan­ tum mechanics. We have not attempted to provide the most extensive collec­ tion possible of information about special functions, but have set ourselves the task of finding an exposition which, based on a unified approach, ensures the possibility of applying the theory in other natural sciences, since it pro­ vides a simple and effective method for the independent solution of problems that arise in practice in physics, engineering and mathematics. For the American edition we have been able to improve a number of proofs; in particular, we have given a new proof of the basic theorem (§3). This is the fundamental theorem of the book; it has now been extended to cover difference equations of hypergeometric type (§§12, 13). Several sections have been simplified and contain new material. We believe that this is the first time that the theory of classical or­ th...

  12. Analytic properties for the honeycomb lattice Green function at the origin

    Science.gov (United States)

    Joyce, G. S.

    2018-05-01

    The analytic properties of the honeycomb lattice Green function are investigated, where is a complex variable which lies in a plane. This double integral defines a single-valued analytic function provided that a cut is made along the real axis from w  =  ‑3 to . In order to analyse the behaviour of along the edges of the cut it is convenient to define the limit function where . It is shown that and can be evaluated exactly for all in terms of various hypergeometric functions, where the argument function is always real-valued and rational. The second-order linear Fuchsian differential equation satisfied by is also used to derive series expansions for and which are valid in the neighbourhood of the regular singular points and . Integral representations are established for and , where with . In particular, it is proved that where J 0(z) and Y 0(z) denote Bessel functions of the first and second kind, respectively. The results derived in the paper are utilized to evaluate the associated logarithmic integral where w lies in the cut plane. A new set of orthogonal polynomials which are connected with the honeycomb lattice Green function are also briefly discussed. Finally, a link between and the theory of Pearson random walks in a plane is established.

  13. Phase function of a spherical particle when scattering an inhomogeneous electromagnetic plane wave.

    Science.gov (United States)

    Frisvad, Jeppe Revall

    2018-04-01

    In absorbing media, electromagnetic plane waves are most often inhomogeneous. Existing solutions for the scattering of an inhomogeneous plane wave by a spherical particle provide no explicit expressions for the scattering components. In addition, current analytical solutions require evaluation of the complex hypergeometric function F 1 2 for every term of a series expansion. In this work, I develop a simpler solution based on associated Legendre functions with argument zero. It is similar to the solution for homogeneous plane waves but with new explicit expressions for the angular dependency of the far-field scattering components, that is, the phase function. I include recurrence formulas for practical evaluation and provide numerical examples to evaluate how well the new expressions match previous work in some limiting cases. The predicted difference in the scattering phase function due to inhomogeneity is not negligible for light entering an absorbing medium at an oblique angle. The presented theory could thus be useful for predicting scattering behavior in dye-based random lasing and in solar cell absorption enhancement.

  14. Comparative analyses identified species-specific functional roles in oral microbial genomes

    Science.gov (United States)

    Chen, Tsute; Gajare, Prasad; Olsen, Ingar; Dewhirst, Floyd E.

    2017-01-01

    ABSTRACT The advent of next generation sequencing is producing more genomic sequences for various strains of many human oral microbial species and allows for insightful functional comparisons at both intra- and inter-species levels. This study performed in-silico functional comparisons for currently available genomic sequences of major species associated with periodontitis including Aggregatibacter actinomycetemcomitans (AA), Porphyromonas gingivalis (PG), Treponema denticola (TD), and Tannerella forsythia (TF), as well as several cariogenic and commensal streptococcal species. Complete or draft sequences were annotated with the RAST to infer structured functional subsystems for each genome. The subsystems profiles were clustered to groups of functions with similar patterns. Functional enrichment and depletion were evaluated based on hypergeometric distribution to identify subsystems that are unique or missing between two groups of genomes. Unique or missing metabolic pathways and biological functions were identified in different species. For example, components involved in flagellar motility were found only in the motile species TD, as expected, with few exceptions scattered in several streptococcal species, likely associated with chemotaxis. Transposable elements were only found in the two Bacteroidales species PG and TF, and half of the AA genomes. Genes involved in CRISPR were prevalent in most oral species. Furthermore, prophage related subsystems were also commonly found in most species except for PG and Streptococcus mutans, in which very few genomes contain prophage components. Comparisons between pathogenic (P) and nonpathogenic (NP) genomes also identified genes potentially important for virulence. Two such comparisons were performed between AA (P) and several A. aphrophilus (NP) strains, and between S. mutans + S. sobrinus (P) and other oral streptococcal species (NP). This comparative genomics approach can be readily used to identify functions unique to

  15. Tensor products of Uq′sl-caret(2)-modules and the big q2-Jacobi function transform

    International Nuclear Information System (INIS)

    Gade, R. M.

    2013-01-01

    Four tensor products of evaluation modules of the quantum affine algebra U q ′ sl-caret(2) obtained from the negative and positive series, the complementary and the strange series representations are investigated. Linear operators R(z) satisfying the intertwining property on finite linear combinations of the canonical basis elements of the tensor products are described in terms of two sets of infinite sums {τ (r,t) } r,t∈Z ≥0 and {τ (r,t) } r,t∈Z ≥0 involving big q 2 -Jacobi functions or related nonterminating basic hypergeometric series. Inhomogeneous recurrence relations can be derived for both sets. Evaluations of the simplest sums provide the corresponding initial conditions. For the first set of sums the relations entail a big q 2 -Jacobi function transform pair. An integral decomposition is obtained for the sum τ (r,t) . A partial description of the relation between the decompositions of the tensor products with respect to U q sl(2) or with respect to its complement in U q ′ sl-caret(2) can be formulated in terms of Askey-Wilson function transforms. For a particular combination of two tensor products, the occurrence of proper U q ′ sl-caret(2)-submodules is discussed.

  16. Matrix transformation relation for the radial integrals of lepton scattering processes

    International Nuclear Information System (INIS)

    Sud, K.K.; Soto Vargas, C.W.; Sharma, D.K.

    1988-01-01

    The radial integrals of many physical problems involving products of initial- and final-state wave functions and the Coulomb interaction are expressible in terms of special cases of generalized hypergeometric functions. In the present work, the generalized hypergeometric functions become elements of a gamma vector which, by means of a partial differential equation and a matrix transformation relation, can be used in calculating the gamma vector in physical regions where the hypergeometric functions are nonconvergent or very slowly converging. Our matrix transformation relation contains the special cases of Gauss' hypergeometric functions 2 F 1 , Appell's hypergeometric functions F 2 , and Lauricella's functions L F transformation relations. The use of contiguous relations along with the transformation relations presented in this paper will facilitate the calculation of physical processes involving such radial integrals

  17. Some exact Bradlow vortex solutions

    Energy Technology Data Exchange (ETDEWEB)

    Gudnason, Sven Bjarke [Institute of Modern Physics, Chinese Academy of Sciences,Lanzhou 730000 (China); Nitta, Muneto [Department of Physics, and Research and Education Center for Natural Sciences, Keio University,Hiyoshi 4-1-1, Yokohama, Kanagawa 223-8521 (Japan)

    2017-05-08

    We consider the Bradlow equation for vortices which was recently found by Manton and find a two-parameter class of analytic solutions in closed form on nontrivial geometries with non-constant curvature. The general solution to our class of metrics is given by a hypergeometric function and the area of the vortex domain by the Gaussian hypergeometric function.

  18. Approximate analytical solutions of Klein-Gordon equation with Hulthen potentials for nonzero angular momentum

    International Nuclear Information System (INIS)

    Chen Changyuan; Sun Dongsheng; Lu Falin

    2007-01-01

    Using the exponential function transformation approach along with an approximation for the centrifugal potential, the radial Klein-Gordon equation with the vector and scalar Hulthen potential is transformed to a hypergeometric differential equation. The approximate analytical solutions of bound states are attained for different l. The analytical energy equation and the unnormalized radial wave functions expressed in terms of hypergeometric polynomials are given

  19. Wilson polynomials/functions and intertwining operators for the generic quantum superintegrable system on the 2-sphere

    Science.gov (United States)

    Miller, W., Jr.; Li, Q.

    2015-04-01

    The Wilson and Racah polynomials can be characterized as basis functions for irreducible representations of the quadratic symmetry algebra of the quantum superintegrable system on the 2-sphere, HΨ = EΨ, with generic 3-parameter potential. Clearly, the polynomials are expansion coefficients for one eigenbasis of a symmetry operator L2 of H in terms of an eigenbasis of another symmetry operator L1, but the exact relationship appears not to have been made explicit. We work out the details of the expansion to show, explicitly, how the polynomials arise and how the principal properties of these functions: the measure, 3-term recurrence relation, 2nd order difference equation, duality of these relations, permutation symmetry, intertwining operators and an alternate derivation of Wilson functions - follow from the symmetry of this quantum system. This paper is an exercise to show that quantum mechancal concepts and recurrence relations for Gausian hypergeometrc functions alone suffice to explain these properties; we make no assumptions about the structure of Wilson polynomial/functions, but derive them from quantum principles. There is active interest in the relation between multivariable Wilson polynomials and the quantum superintegrable system on the n-sphere with generic potential, and these results should aid in the generalization. Contracting function space realizations of irreducible representations of this quadratic algebra to the other superintegrable systems one can obtain the full Askey scheme of orthogonal hypergeometric polynomials. All of these contractions of superintegrable systems with potential are uniquely induced by Wigner Lie algebra contractions of so(3, C) and e(2,C). All of the polynomials produced are interpretable as quantum expansion coefficients. It is important to extend this process to higher dimensions.

  20. Wilson polynomials/functions and intertwining operators for the generic quantum superintegrable system on the 2-sphere

    International Nuclear Information System (INIS)

    Miller, W Jr; Li, Q

    2015-01-01

    The Wilson and Racah polynomials can be characterized as basis functions for irreducible representations of the quadratic symmetry algebra of the quantum superintegrable system on the 2-sphere, HΨ = EΨ, with generic 3-parameter potential. Clearly, the polynomials are expansion coefficients for one eigenbasis of a symmetry operator L 2 of H in terms of an eigenbasis of another symmetry operator L 1 , but the exact relationship appears not to have been made explicit. We work out the details of the expansion to show, explicitly, how the polynomials arise and how the principal properties of these functions: the measure, 3-term recurrence relation, 2nd order difference equation, duality of these relations, permutation symmetry, intertwining operators and an alternate derivation of Wilson functions - follow from the symmetry of this quantum system. This paper is an exercise to show that quantum mechancal concepts and recurrence relations for Gausian hypergeometrc functions alone suffice to explain these properties; we make no assumptions about the structure of Wilson polynomial/functions, but derive them from quantum principles. There is active interest in the relation between multivariable Wilson polynomials and the quantum superintegrable system on the n-sphere with generic potential, and these results should aid in the generalization. Contracting function space realizations of irreducible representations of this quadratic algebra to the other superintegrable systems one can obtain the full Askey scheme of orthogonal hypergeometric polynomials. All of these contractions of superintegrable systems with potential are uniquely induced by Wigner Lie algebra contractions of so(3, C) and e(2,C). All of the polynomials produced are interpretable as quantum expansion coefficients. It is important to extend this process to higher dimensions. (paper)

  1. Recursive evaluation of space-time lattice Green's functions

    International Nuclear Information System (INIS)

    De Hon, Bastiaan P; Arnold, John M

    2012-01-01

    Up to a multiplicative constant, the lattice Green's function (LGF) as defined in condensed matter physics and lattice statistical mechanics is equivalent to the Z-domain counterpart of the finite-difference time-domain Green's function (GF) on a lattice. Expansion of a well-known integral representation for the LGF on a ν-dimensional hyper-cubic lattice in powers of Z −1 and application of the Chu–Vandermonde identity results in ν − 1 nested finite-sum representations for discrete space-time GFs. Due to severe numerical cancellations, these nested finite sums are of little practical use. For ν = 2, the finite sum may be evaluated in closed form in terms of a generalized hypergeometric function. For special lattice points, that representation simplifies considerably, while on the other hand the finite-difference stencil may be used to derive single-lattice-point second-order recurrence schemes for generating 2D discrete space-time GF time sequences on the fly. For arbitrary symbolic lattice points, Zeilberger's algorithm produces a third-order recurrence operator with polynomial coefficients of the sixth degree. The corresponding recurrence scheme constitutes the most efficient numerical method for the majority of lattice points, in spite of the fact that for explicit numeric lattice points the associated third-order recurrence operator is not the minimum recurrence operator. As regards the asymptotic bounds for the possible solutions to the recurrence scheme, Perron's theorem precludes factorial or exponential growth. Along horizontal lattices directions, rapid initial growth does occur, but poses no problems in augmented dynamic-range fixed precision arithmetic. By analysing long-distance wave propagation along a horizontal lattice direction, we have concluded that the chirp-up oscillations of the discrete space-time GF are the root cause of grid dispersion anisotropy. With each factor of ten increase in the lattice distance, one would have to roughly

  2. Spectral inverse problem for q-deformed harmonic oscillator

    Indian Academy of Sciences (India)

    - out direct ... concepts, exact knowledge of the spectrum is not enough for the reconstruction of ..... As the superpotential is related to the ground-state wave function, we demand ..... q-hypergeometric function multiplied by some weight factor.

  3. Comparison of two matrix data structures for advanced CSM testbed applications

    Science.gov (United States)

    Regelbrugge, M. E.; Brogan, F. A.; Nour-Omid, B.; Rankin, C. C.; Wright, M. A.

    1989-01-01

    The first section describes data storage schemes presently used by the Computational Structural Mechanics (CSM) testbed sparse matrix facilities and similar skyline (profile) matrix facilities. The second section contains a discussion of certain features required for the implementation of particular advanced CSM algorithms, and how these features might be incorporated into the data storage schemes described previously. The third section presents recommendations, based on the discussions of the prior sections, for directing future CSM testbed development to provide necessary matrix facilities for advanced algorithm implementation and use. The objective is to lend insight into the matrix structures discussed and to help explain the process of evaluating alternative matrix data structures and utilities for subsequent use in the CSM testbed.

  4. Generalized functions

    CERN Document Server

    Gelfand, I M; Graev, M I; Vilenkin, N Y; Pyatetskii-Shapiro, I I

    Volume 1 is devoted to basics of the theory of generalized functions. The first chapter contains main definitions and most important properties of generalized functions as functional on the space of smooth functions with compact support. The second chapter talks about the Fourier transform of generalized functions. In Chapter 3, definitions and properties of some important classes of generalized functions are discussed; in particular, generalized functions supported on submanifolds of lower dimension, generalized functions associated with quadratic forms, and homogeneous generalized functions are studied in detail. Many simple basic examples make this book an excellent place for a novice to get acquainted with the theory of generalized functions. A long appendix presents basics of generalized functions of complex variables.

  5. Chudnovsky-Ramanujan Type Formulae for the Legendre Family

    OpenAIRE

    Chen, Imin; Glebov, Gleb

    2017-01-01

    We apply the method established in our previous work to derive a Chudnovsky-Ramanujan type formula for the Legendre family of elliptic curves. As a result, we prove two identities for $1/\\pi$ in terms of hypergeometric functions.

  6. Holonomic functions of several complex variables and singularities of anisotropic Ising n-fold integrals

    Science.gov (United States)

    Boukraa, S.; Hassani, S.; Maillard, J.-M.

    2012-12-01

    Focusing on examples associated with holonomic functions, we try to bring new ideas on how to look at phase transitions, for which the critical manifolds are not points but curves depending on a spectral variable, or even fill higher dimensional submanifolds. Lattice statistical mechanics often provides a natural (holonomic) framework to perform singularity analysis with several complex variables that would, in the most general mathematical framework, be too complex, or simply could not be defined. In a learn-by-example approach, considering several Picard-Fuchs systems of two-variables ‘above’ Calabi-Yau ODEs, associated with double hypergeometric series, we show that D-finite (holonomic) functions are actually a good framework for finding properly the singular manifolds. The singular manifolds are found to be genus-zero curves. We then analyze the singular algebraic varieties of quite important holonomic functions of lattice statistical mechanics, the n-fold integrals χ(n), corresponding to the n-particle decomposition of the magnetic susceptibility of the anisotropic square Ising model. In this anisotropic case, we revisit a set of so-called Nickelian singularities that turns out to be a two-parameter family of elliptic curves. We then find the first set of non-Nickelian singularities for χ(3) and χ(4), that also turns out to be rational or elliptic curves. We underline the fact that these singular curves depend on the anisotropy of the Ising model, or, equivalently, that they depend on the spectral parameter of the model. This has important consequences on the physical nature of the anisotropic χ(n)s which appear to be highly composite objects. We address, from a birational viewpoint, the emergence of families of elliptic curves, and that of Calabi-Yau manifolds on such problems. We also address the question of singularities of non-holonomic functions with a discussion on the accumulation of these singular curves for the non-holonomic anisotropic full

  7. Holonomic functions of several complex variables and singularities of anisotropic Ising n-fold integrals

    International Nuclear Information System (INIS)

    Boukraa, S; Hassani, S; Maillard, J-M

    2012-01-01

    Focusing on examples associated with holonomic functions, we try to bring new ideas on how to look at phase transitions, for which the critical manifolds are not points but curves depending on a spectral variable, or even fill higher dimensional submanifolds. Lattice statistical mechanics often provides a natural (holonomic) framework to perform singularity analysis with several complex variables that would, in the most general mathematical framework, be too complex, or simply could not be defined. In a learn-by-example approach, considering several Picard–Fuchs systems of two-variables ‘above’ Calabi–Yau ODEs, associated with double hypergeometric series, we show that D-finite (holonomic) functions are actually a good framework for finding properly the singular manifolds. The singular manifolds are found to be genus-zero curves. We then analyze the singular algebraic varieties of quite important holonomic functions of lattice statistical mechanics, the n-fold integrals χ (n) , corresponding to the n-particle decomposition of the magnetic susceptibility of the anisotropic square Ising model. In this anisotropic case, we revisit a set of so-called Nickelian singularities that turns out to be a two-parameter family of elliptic curves. We then find the first set of non-Nickelian singularities for χ (3) and χ (4) , that also turns out to be rational or elliptic curves. We underline the fact that these singular curves depend on the anisotropy of the Ising model, or, equivalently, that they depend on the spectral parameter of the model. This has important consequences on the physical nature of the anisotropic χ (n) s which appear to be highly composite objects. We address, from a birational viewpoint, the emergence of families of elliptic curves, and that of Calabi–Yau manifolds on such problems. We also address the question of singularities of non-holonomic functions with a discussion on the accumulation of these singular curves for the non

  8. New solutions of Heun's general equation

    International Nuclear Information System (INIS)

    Ishkhanyan, Artur; Suominen, Kalle-Antti

    2003-01-01

    We show that in four particular cases the derivative of the solution of Heun's general equation can be expressed in terms of a solution to another Heun's equation. Starting from this property, we use the Gauss hypergeometric functions to construct series solutions to Heun's equation for the mentioned cases. Each of the hypergeometric functions involved has correct singular behaviour at only one of the singular points of the equation; the sum, however, has correct behaviour. (letter to the editor)

  9. Clebsch-Gordan and Racah coefficients of SUpq(2)

    International Nuclear Information System (INIS)

    Kachurik, I.I.

    1993-01-01

    Explicit expressions for the Clebsch-Gordan coefficients and for the Racah coefficients of the two-parametric quantum algebra SU pq (2) are derived. They are given as finite sums and as terminating basic hypergeometric functions 3 φ 2 and 4 φ 3 . It is indicated how other expressions for these coefficients can be derived with the help of basic hypergeometric functions. (author). 11 refs

  10. Tree-level gluon amplitudes on the celestial sphere

    Science.gov (United States)

    Schreiber, Anders Ø.; Volovich, Anastasia; Zlotnikov, Michael

    2018-06-01

    Pasterski, Shao and Strominger have recently proposed that massless scattering amplitudes can be mapped to correlators on the celestial sphere at infinity via a Mellin transform. We apply this prescription to arbitrary n-point tree-level gluon amplitudes. The Mellin transforms of MHV amplitudes are given by generalized hypergeometric functions on the Grassmannian Gr (4 , n), while generic non-MHV amplitudes are given by more complicated Gelfand A-hypergeometric functions.

  11. Crystallization of bi-functional ligand protein complexes.

    Science.gov (United States)

    Antoni, Claudia; Vera, Laura; Devel, Laurent; Catalani, Maria Pia; Czarny, Bertrand; Cassar-Lajeunesse, Evelyn; Nuti, Elisa; Rossello, Armando; Dive, Vincent; Stura, Enrico Adriano

    2013-06-01

    Homodimerization is important in signal transduction and can play a crucial role in many other biological systems. To obtaining structural information for the design of molecules able to control the signalization pathways, the proteins involved will have to be crystallized in complex with ligands that induce dimerization. Bi-functional drugs have been generated by linking two ligands together chemically and the relative crystallizability of complexes with mono-functional and bi-functional ligands has been evaluated. There are problems associated with crystallization with such ligands, but overall, the advantages appear to be greater than the drawbacks. The study involves two matrix metalloproteinases, MMP-12 and MMP-9. Using flexible and rigid linkers we show that it is possible to control the crystal packing and that by changing the ligand-enzyme stoichiometric ratio, one can toggle between having one bi-functional ligand binding to two enzymes and having the same ligand bound to each enzyme. The nature of linker and its point of attachment on the ligand can be varied to aid crystallization, and such variations can also provide valuable structural information about the interactions made by the linker with the protein. We report here the crystallization and structure determination of seven ligand-dimerized complexes. These results suggest that the use of bi-functional drugs can be extended beyond the realm of protein dimerization to include all drug design projects. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. Functional Boxplots

    KAUST Repository

    Sun, Ying

    2011-01-01

    This article proposes an informative exploratory tool, the functional boxplot, for visualizing functional data, as well as its generalization, the enhanced functional boxplot. Based on the center outward ordering induced by band depth for functional data, the descriptive statistics of a functional boxplot are: the envelope of the 50% central region, the median curve, and the maximum non-outlying envelope. In addition, outliers can be detected in a functional boxplot by the 1.5 times the 50% central region empirical rule, analogous to the rule for classical boxplots. The construction of a functional boxplot is illustrated on a series of sea surface temperatures related to the El Niño phenomenon and its outlier detection performance is explored by simulations. As applications, the functional boxplot and enhanced functional boxplot are demonstrated on children growth data and spatio-temporal U.S. precipitation data for nine climatic regions, respectively. This article has supplementary material online. © 2011 American Statistical Association.

  13. Orbit Functions

    Directory of Open Access Journals (Sweden)

    Anatoliy Klimyk

    2006-01-01

    Full Text Available In the paper, properties of orbit functions are reviewed and further developed. Orbit functions on the Euclidean space E_n are symmetrized exponential functions. The symmetrization is fulfilled by a Weyl group corresponding to a Coxeter-Dynkin diagram. Properties of such functions will be described. An orbit function is the contribution to an irreducible character of a compact semisimple Lie group G of rank n from one of its Weyl group orbits. It is shown that values of orbit functions are repeated on copies of the fundamental domain F of the affine Weyl group (determined by the initial Weyl group in the entire Euclidean space E_n. Orbit functions are solutions of the corresponding Laplace equation in E_n, satisfying the Neumann condition on the boundary of F. Orbit functions determine a symmetrized Fourier transform and a transform on a finite set of points.

  14. Functional displays

    International Nuclear Information System (INIS)

    Angelis De, F.; Haentjens, J.

    1995-01-01

    The Functional Displays are directly derived from the Man-Machine Design key document: Function-Based Task Analysis. The presentation defines and describes the goals-means structure of the plant function along with applicable control volumes and parameters of interest. The purpose of the subject is to show, through an example of a preliminary design, what the main parts of a function are. (3 figs.)

  15. Functional Programming

    OpenAIRE

    Chitil, Olaf

    2009-01-01

    Functional programming is a programming paradigm like object-oriented programming and logic programming. Functional programming comprises both a specific programming style and a class of programming languages that encourage and support this programming style. Functional programming enables the programmer to describe an algorithm on a high-level, in terms of the problem domain, without having to deal with machine-related details. A program is constructed from functions that only map inputs to ...

  16. Functionalized amphipols

    DEFF Research Database (Denmark)

    Della Pia, Eduardo Antonio; Hansen, Randi Westh; Zoonens, Manuela

    2014-01-01

    Amphipols are amphipathic polymers that stabilize membrane proteins isolated from their native membrane. They have been functionalized with various chemical groups in the past years for protein labeling and protein immobilization. This large toolbox of functionalized amphipols combined with their...... surfaces for various applications in synthetic biology. This review summarizes the properties of functionalized amphipols suitable for synthetic biology approaches....

  17. Lightness functions

    DEFF Research Database (Denmark)

    Campi, Stefano; Gardner, Richard; Gronchi, Paolo

    2012-01-01

    Variants of the brightness function of a convex body K in n-dimensional Euclidean are investigated. The Lambertian lightness function L(K; v , w ) gives the total reflected light resulting from illumination by a light source at infinity in the direction w that is visible when looking...... in the direction v . The partial brightness function R( K ; v , w ) gives the area of the projection orthogonal to v of the portion of the surface of K that is both illuminated by a light source from the direction w and visible when looking in the direction v . A class of functions called lightness functions...... is introduced that includes L(K;.) and R(K;.) as special cases. Much of the theory of the brightness function like uniqueness, stability, and the existence and properties of convex bodies of maximal and minimal volume with finitely many function values equal to those of a given convex body, is extended...

  18. Functional analysis

    CERN Document Server

    Kantorovich, L V

    1982-01-01

    Functional Analysis examines trends in functional analysis as a mathematical discipline and the ever-increasing role played by its techniques in applications. The theory of topological vector spaces is emphasized, along with the applications of functional analysis to applied analysis. Some topics of functional analysis connected with applications to mathematical economics and control theory are also discussed. Comprised of 18 chapters, this book begins with an introduction to the elements of the theory of topological spaces, the theory of metric spaces, and the theory of abstract measure space

  19. Functional Boxplots

    KAUST Repository

    Sun, Ying; Genton, Marc G.

    2011-01-01

    data, the descriptive statistics of a functional boxplot are: the envelope of the 50% central region, the median curve, and the maximum non-outlying envelope. In addition, outliers can be detected in a functional boxplot by the 1.5 times the 50% central

  20. Functional coma.

    Science.gov (United States)

    Ludwig, L; McWhirter, L; Williams, S; Derry, C; Stone, J

    2016-01-01

    Functional coma - here defined as a prolonged motionless dissociative attack with absent or reduced response to external stimuli - is a relatively rare presentation. In this chapter we examine a wide range of terms used to describe states of unresponsiveness in which psychologic factors are relevant to etiology, such as depressive stupor, catatonia, nonepileptic "pseudostatus," and factitious disorders, and discuss the place of functional or psychogenic coma among these. Historically, diagnosis of functional coma has sometimes been reached after prolonged investigation and exclusion of other diagnoses. However, as is the case with other functional disorders, diagnosis should preferably be made on the basis of positive findings that provide evidence of inconsistency between an apparent comatose state and normal waking nervous system functioning. In our review of physical signs, we find some evidence for the presence of firm resistance to eye opening as reasonably sensitive and specific for functional coma, as well as the eye gaze sign, in which patients tend to look to the ground when turned on to one side. Noxious stimuli such as Harvey's sign (application of high-frequency vibrating tuning fork to the nasal mucosa) can also be helpful, although patients with this disorder are often remarkably unresponsive to usually painful stimuli, particularly as more commonly applied using sternal or nail bed pressure. The use of repeated painful stimuli is therefore not recommended. We also discuss the role of general anesthesia and other physiologic triggers to functional coma. © 2016 Elsevier B.V. All rights reserved.

  1. Rhinoplasty (Functional)

    Science.gov (United States)

    ... RESOURCES Medical Societies Patient Education About this Website Font Size + - Home > TREATMENTS > Rhinoplasty (Functional) Nasal/Sinus Irrigation ... performed to restore breathing, it typically necessitates some type of change to the appearance of the nose. ...

  2. Functional tremor.

    Science.gov (United States)

    Schwingenschuh, P; Deuschl, G

    2016-01-01

    Functional tremor is the commonest reported functional movement disorder. A confident clinical diagnosis of functional tremor is often possible based on the following "positive" criteria: a sudden tremor onset, unusual disease course, often with fluctuations or remissions, distractibility of the tremor if attention is removed from the affected body part, tremor entrainment, tremor variability, and a coactivation sign. Many patients show excessive exhaustion during examination. Other somatizations may be revealed in the medical history and patients may show additional functional neurologic symptoms and signs. In cases where the clinical diagnosis remains challenging, providing a "laboratory-supported" level of certainty aids an early positive diagnosis. In rare cases, in which the distinction from Parkinson's disease is difficult, dopamine transporter single-photon emission computed tomography (DAT-SPECT) can be indicated. © 2016 Elsevier B.V. All rights reserved.

  3. Cognitive Function

    Science.gov (United States)

    Because chemicals can adversely affect cognitive function in humans, considerable effort has been made to characterize their effects using animal models. Information from such models will be necessary to: evaluate whether chemicals identified as potentially neurotoxic by screenin...

  4. Functional unparsing

    DEFF Research Database (Denmark)

    Danvy, Olivier

    2000-01-01

    A string-formatting function such as printf in C seemingly requires dependent types, because its control string determines the rest of its arguments. Examples: formula here We show how changing the representation of the control string makes it possible to program printf in ML (which does not allow...... dependent types). The result is well typed and perceptibly more efficient than the corresponding library functions in Standard ML of New Jersey and in Caml....

  5. Functional Unparsing

    DEFF Research Database (Denmark)

    Danvy, Olivier

    1998-01-01

    A string-formatting function such as printf in C seemingly requires dependent types, because its control string determines the rest of its arguments. We show how changing the representation of the control string makes it possible to program printf in ML (which does not allow dependent types......). The result is well typed and perceptibly more efficient than the corresponding library functions in Standard ML of New Jersey and in Caml....

  6. Overlap functions

    Czech Academy of Sciences Publication Activity Database

    Bustince, H.; Fernández, J.; Mesiar, Radko; Montero, J.; Orduna, R.

    2010-01-01

    Roč. 72, 3-4 (2010), s. 1488-1499 ISSN 0362-546X R&D Projects: GA ČR GA402/08/0618 Institutional research plan: CEZ:AV0Z10750506 Keywords : t-norm * Migrative property * Homogeneity property * Overlap function Subject RIV: BA - General Mathematics Impact factor: 1.279, year: 2010 http://library.utia.cas.cz/separaty/2009/E/mesiar-overlap functions.pdf

  7. Bessel functions

    CERN Document Server

    Nambudiripad, K B M

    2014-01-01

    After presenting the theory in engineers' language without the unfriendly abstraction of pure mathematics, several illustrative examples are discussed in great detail to see how the various functions of the Bessel family enter into the solution of technically important problems. Axisymmetric vibrations of a circular membrane, oscillations of a uniform chain, heat transfer in circular fins, buckling of columns of varying cross-section, vibrations of a circular plate and current density in a conductor of circular cross-section are considered. The problems are formulated purely from physical considerations (using, for example, Newton's law of motion, Fourier's law of heat conduction electromagnetic field equations, etc.) Infinite series expansions, recurrence relations, manipulation of expressions involving Bessel functions, orthogonality and expansion in Fourier-Bessel series are also covered in some detail. Some important topics such as asymptotic expansions, generating function and Sturm-Lioville theory are r...

  8. Functional inequalities

    CERN Document Server

    Ghoussoub, Nassif

    2013-01-01

    The book describes how functional inequalities are often manifestations of natural mathematical structures and physical phenomena, and how a few general principles validate large classes of analytic/geometric inequalities, old and new. This point of view leads to "systematic" approaches for proving the most basic inequalities, but also for improving them, and for devising new ones--sometimes at will and often on demand. These general principles also offer novel ways for estimating best constants and for deciding whether these are attained in appropriate function spaces. As such, improvements of Hardy and Hardy-Rellich type inequalities involving radially symmetric weights are variational manifestations of Sturm's theory on the oscillatory behavior of certain ordinary differential equations. On the other hand, most geometric inequalities, including those of Sobolev and Log-Sobolev type, are simply expressions of the convexity of certain free energy functionals along the geodesics on the Wasserstein manifold of...

  9. Algebraic functions

    CERN Document Server

    Bliss, Gilbert Ames

    1933-01-01

    This book, immediately striking for its conciseness, is one of the most remarkable works ever produced on the subject of algebraic functions and their integrals. The distinguishing feature of the book is its third chapter, on rational functions, which gives an extremely brief and clear account of the theory of divisors.... A very readable account is given of the topology of Riemann surfaces and of the general properties of abelian integrals. Abel's theorem is presented, with some simple applications. The inversion problem is studied for the cases of genus zero and genus unity. The chapter on t

  10. Functional dyspepsia

    NARCIS (Netherlands)

    Kleibeuker, JH; Thijs, JC

    2004-01-01

    Purpose of review Functional dyspepsia is a common disorder, most of the time of unknown etiology and with variable pathophysiology. Therapy has been and still is largely empirical. Data from recent studies provide new clues for targeted therapy based on knowledge of etiology and pathophysiologic

  11. Functional Literacy

    Directory of Open Access Journals (Sweden)

    Fani Nolimal

    2000-12-01

    Full Text Available The author first defines literacy as the ability of co-operation in all fields of life and points at the features of illiterate or semi-literate individuals. The main stress is laid upon the assessment of literacy and illiteracy. In her opinion the main weak­ ness of this kind of evaluation are its vague psycho-metric characteristics, which leads to results valid in a single geographical or cultural environment only. She also determines the factors causing illiteracy, and she states that the level of functional literacy is more and more becoming a national indicator of successfulness.

  12. Lung function

    International Nuclear Information System (INIS)

    Sorichter, S.

    2009-01-01

    The term lung function is often restricted to the assessment of volume time curves measured at the mouth. Spirometry includes the assessment of lung volumes which can be mobilised with the corresponding flow-volume curves. In addition, lung volumes that can not be mobilised, such as the residual volume, or only partially as FRC and TLC can be measured by body plethysmography combined with the determination of the airway resistance. Body plethysmography allows the correct positioning of forced breathing manoeuvres on the volume-axis, e.g. before and after pharmacotherapy. Adding the CO single breath transfer factor (T LCO ), which includes the measurement of the ventilated lung volume using He, enables a clear diagnosis of different obstructive, restrictive or mixed ventilatory defects with and without trapped air. Tests of reversibility and provocation, as well as the assessment of inspiratory mouth pressures (PI max , P 0.1 ) help to classify the underlying disorder and to clarify treatment strategies. For further information and to complete the diagnostic of disturbances of the ventilation, diffusion and/or perfusion (capillar-)arterial bloodgases at rest and under physical strain sometimes amended by ergospirometry are recommended. Ideally, lung function measurements are amended by radiological and nuclear medicine techniques. (orig.) [de

  13. Functional phlebology

    International Nuclear Information System (INIS)

    Weber, J.; May, R.; Biland, L.; Endert, G.; Gottlob, R.; Justich, E.; Luebcke, P.; Mignon, G.; Moltz, L.; Partsch, H.; Petter, A.; Ritter, H.; Soerensen, R.; Widmer, L.K.; Widmer, M.T.; Zemp, E.

    1990-01-01

    The book presents a complete survey of the problems occurring in the venous system of the legs, pelvis, and abdomen. The material is arranged in the following main chapters: (1) Introduction to the phlebology of the low-pressure system in the lower part of the body; (2) Phlebographic methods; (3) Instrumented function studies and methods; (4) Pathologic findings; (5) Diagnostic methods and vein therapy; (6) Interventional radiology; (7) Expert opinions on venous lesions including insurance aspects. The first chapter encompasses a section briefly discussing the available instrumented diagnostic imaging methods. In view of the novel imaging methods, namely digital subtraction phlebology, sonography, CT and MRI, the classical phlebography remains the gold standard, so to speak: all currently available phlebographic methods for imaging the venes in the legs, pelvis and abdomen are explained and comparatively evaluated. Instrumented function tests such as Doppler effect ultrasound testing, plethysmography, peripheral and central phlebodynamometry (venous pressure measurement) are analysed for their diagnostic value and as alternative or supplementing techniques in comparison to phlebology. (orig./MG) With 843 figs., 101 tabs [de

  14. Functional Credentials

    Directory of Open Access Journals (Sweden)

    Deuber Dominic

    2018-04-01

    Full Text Available A functional credential allows a user to anonymously prove possession of a set of attributes that fulfills a certain policy. The policies are arbitrary polynomially computable predicates that are evaluated over arbitrary attributes. The key feature of this primitive is the delegation of verification to third parties, called designated verifiers. The delegation protects the privacy of the policy: A designated verifier can verify that a user satisfies a certain policy without learning anything about the policy itself. We illustrate the usefulness of this property in different applications, including outsourced databases with access control. We present a new framework to construct functional credentials that does not require (non-interactive zero-knowledge proofs. This is important in settings where the statements are complex and thus the resulting zero-knowledge proofs are not efficient. Our construction is based on any predicate encryption scheme and the security relies on standard assumptions. A complexity analysis and an experimental evaluation confirm the practicality of our approach.

  15. Functional Angioplasty

    Directory of Open Access Journals (Sweden)

    Rohit Tewari

    2013-01-01

    Full Text Available Coronary angiography underestimates or overestimates lesion severity, but still remains the cornerstone in the decision making for revascularization for an overwhelming majority of interventional cardiologists. Guidelines recommend and endorse non invasive functional evaluation ought to precede revascularization. In real world practice, this is adopted in less than 50% of patients who go on to have some form of revascularization. Fractional flow reserve (FFR is the ratio of maximal blood flow in a stenotic coronary relative to maximal flow in the same vessel, were it normal. Being independent of changes in heart rate, BP or prior infarction; and take into account the contribution of collateral blood flow. It is a majorly specific index with a reasonably high sensitivity (88%, specificity (100%, positive predictive value (100%, and overall accuracy (93%. Whilst FFR provides objective determination of ischemia and helps select appropriate candidates for revascularization (for both CABG and PCI in to cath lab itself before intervention, whereas intravascular ultrasound/optical coherence tomography guidance in PCI can secure the procedure by optimizing stent expansion. Functional angioplasty simply is incorporating both intravascular ultrasound and FFR into our daily Intervention practices.

  16. Analytic result for the one-loop scalar pentagon integral with massless propagators

    International Nuclear Information System (INIS)

    Kniehl, Bernd A.; Tarasov, Oleg V.

    2010-01-01

    The method of dimensional recurrences proposed by one of the authors (O. V.Tarasov, 1996) is applied to the evaluation of the pentagon-type scalar integral with on-shell external legs and massless internal lines. For the first time, an analytic result valid for arbitrary space-time dimension d and five arbitrary kinematic variables is presented. An explicit expression in terms of the Appell hypergeometric function F 3 and the Gauss hypergeometric function 2 F 1 , both admitting one-fold integral representations, is given. In the case when one kinematic variable vanishes, the integral reduces to a combination of Gauss hypergeometric functions 2 F 1 . For the case when one scalar invariant is large compared to the others, the asymptotic values of the integral in terms of Gauss hypergeometric functions 2 F 1 are presented in d=2-2ε, 4-2ε, and 6-2ε dimensions. For multi-Regge kinematics, the asymptotic value of the integral in d=4-2ε dimensions is given in terms of the Appell function F 3 and the Gauss hypergeometric function 2 F 1 . (orig.)

  17. Analytic result for the one-loop scalar pentagon integral with massless propagators

    Energy Technology Data Exchange (ETDEWEB)

    Kniehl, Bernd A.; Tarasov, Oleg V. [Hamburg Univ. (Germany). II. Inst. fuer Theoretische Physik

    2010-01-15

    The method of dimensional recurrences proposed by one of the authors (O. V.Tarasov, 1996) is applied to the evaluation of the pentagon-type scalar integral with on-shell external legs and massless internal lines. For the first time, an analytic result valid for arbitrary space-time dimension d and five arbitrary kinematic variables is presented. An explicit expression in terms of the Appell hypergeometric function F{sub 3} and the Gauss hypergeometric function {sub 2}F{sub 1}, both admitting one-fold integral representations, is given. In the case when one kinematic variable vanishes, the integral reduces to a combination of Gauss hypergeometric functions {sub 2}F{sub 1}. For the case when one scalar invariant is large compared to the others, the asymptotic values of the integral in terms of Gauss hypergeometric functions {sub 2}F{sub 1} are presented in d=2-2{epsilon}, 4-2{epsilon}, and 6-2{epsilon} dimensions. For multi-Regge kinematics, the asymptotic value of the integral in d=4-2{epsilon} dimensions is given in terms of the Appell function F{sub 3} and the Gauss hypergeometric function {sub 2}F{sub 1}. (orig.)

  18. Analytic result for the one-loop scalar pentagon integral with massless propagators

    International Nuclear Information System (INIS)

    Kniehl, Bernd A.; Tarasov, Oleg V.

    2010-01-01

    The method of dimensional recurrences proposed by Tarasov (1996, 2000) is applied to the evaluation of the pentagon-type scalar integral with on-shell external legs and massless internal lines. For the first time, an analytic result valid for arbitrary space-time dimension d and five arbitrary kinematic variables is presented. An explicit expression in terms of the Appell hypergeometric function F 3 and the Gauss hypergeometric function 2 F 1 , both admitting one-fold integral representations, is given. In the case when one kinematic variable vanishes, the integral reduces to a combination of Gauss hypergeometric functions 2 F 1 . For the case when one scalar invariant is large compared to the others, the asymptotic values of the integral in terms of Gauss hypergeometric functions 2 F 1 are presented in d=2-2ε, 4-2ε, and 6-2ε dimensions. For multi-Regge kinematics, the asymptotic value of the integral in d=4-2ε dimensions is given in terms of the Appell function F 3 and the Gauss hypergeometric function 2 F 1 .

  19. Thyroid Function Tests

    Science.gov (United States)

    ... Home » Thyroid Function Tests Leer en Español Thyroid Function Tests FUNCTION HOW DOES THE THYROID GLAND FUNCTION? ... Cancer Thyroid Nodules in Children and Adolescents Thyroid Function Tests Resources Thyroid Function Tests Brochure PDF En ...

  20. Functional materials

    International Nuclear Information System (INIS)

    Park, J. Y.; Hong, G. W.; Lee, H. J.

    2002-05-01

    Development of fabrication process of functional ceramic materials, evaluation of characteristics and experiments for understanding of irradiation behavior of ceramics were carried out for application of ceramics to the nuclear industry. The developed processes were the SiC surface coating technology with large area for improvement of wear resistance and corrosion resistance, the fabrication technology of SiC composites for excellent irradiation resistance, performance improvement technology of SiC fiber and nano-sized powder processing by combustion ignition and spray. Typical results were CVD SiC coating with diameter of 25cm and thickness of 100μm, highly dense SiC composite by F-CVI, heat-treating technology of SiC fiber using B4C power, and nano-sized powders of ODS-Cu, Li-based breeding materials, Ni-based metal powders with primary particle diameter of 20∼50nm. Furthermore, test equipment, data productions and damage evaluations were performed to understand corrosion resistance and wear resistance of alumina, silicon carbide and silicon nitride under PWR or PHWR operation conditions. Experimental procedures and basic technologies for evaluation of irradiation behavior were also established. Additionally, highly reactive precursor powders were developed by various technologies and the powders were applied to the fabrication of 100 m long Ag/Bi-2223 multi-filamentary wires. High Tc magnets and fly wheel for energy storage were developed, as well

  1. Functional Programming in R

    DEFF Research Database (Denmark)

    Mailund, Thomas

    Master functions and discover how to write functional programs in R. In this book, you'll make your functions pure by avoiding side-effects; you’ll write functions that manipulate other functions, and you’ll construct complex functions using simpler functions as building blocks. In Functional...... Programming in R, you’ll see how we can replace loops, which can have side-effects, with recursive functions that can more easily avoid them. In addition, the book covers why you shouldn't use recursion when loops are more efficient and how you can get the best of both worlds. Functional programming...... functions by combining simpler functions. You will: Write functions in R including infix operators and replacement functions Create higher order functions Pass functions to other functions and start using functions as data you can manipulate Use Filer, Map and Reduce functions to express the intent behind...

  2. Resummed coefficient function for the shape function

    OpenAIRE

    Aglietti, U.

    2001-01-01

    We present a leading evaluation of the resummed coefficient function for the shape function. It is also shown that the coefficient function is short-distance-dominated. Our results allow relating the shape function computed on the lattice to the physical QCD distributions.

  3. Modular forms, Schwarzian conditions, and symmetries of differential equations in physics

    Science.gov (United States)

    Abdelaziz, Y.; Maillard, J.-M.

    2017-05-01

    We give examples of infinite order rational transformations that leave linear differential equations covariant. These examples are non-trivial yet simple enough illustrations of exact representations of the renormalization group. We first illustrate covariance properties on order-two linear differential operators associated with identities relating the same {}_2F1 hypergeometric function with different rational pullbacks. These rational transformations are solutions of a differentially algebraic equation that already emerged in a paper by Casale on the Galoisian envelopes. We provide two new and more general results of the previous covariance by rational functions: a new Heun function example and a higher genus {}_2F1 hypergeometric function example. We then focus on identities relating the same {}_2F1 hypergeometric function with two different algebraic pullback transformations: such remarkable identities correspond to modular forms, the algebraic transformations being solution of another differentially algebraic Schwarzian equation that also emerged in Casale’s paper. Further, we show that the first differentially algebraic equation can be seen as a subcase of the last Schwarzian differential condition, the restriction corresponding to a factorization condition of some associated order-two linear differential operator. Finally, we also explore generalizations of these results, for instance, to {}_3F2 , hypergeometric functions, and show that one just reduces to the previous {}_2F1 cases through a Clausen identity. The question of the reduction of these Schwarzian conditions to modular correspondences remains an open question. In a _2F1 hypergeometric framework the Schwarzian condition encapsulates all the modular forms and modular equations of the theory of elliptic curves, but these two conditions are actually richer than elliptic curves or {}_2F1 hypergeometric functions, as can be seen on the Heun and higher genus example. This work is a strong incentive to

  4. Time functions function best as functions of multiple times

    NARCIS (Netherlands)

    Desain, P.; Honing, H.

    1992-01-01

    This article presents an elegant way of representing control functions at an abstractlevel. It introduces time functions that have multiple times as arguments. In this waythe generalized concept of a time function can support absolute and relative kinds of time behavior. Furthermore the

  5. Solution of Differential Equations with Polynomial Coefficients with the Aid of an Analytic Continuation of Laplace Transform

    Directory of Open Access Journals (Sweden)

    Tohru Morita

    2016-03-01

    Full Text Available In a series of papers, we discussed the solution of Laplace’s differential equation (DE by using fractional calculus, operational calculus in the framework of distribution theory, and Laplace transform. The solutions of Kummer’s DE, which are expressed by the confluent hypergeometric functions, are obtained with the aid of the analytic continuation (AC of Riemann–Liouville fractional derivative (fD and the distribution theory in the space D′R or the AC of Laplace transform. We now obtain the solutions of the hypergeometric DE, which are expressed by the hypergeometric functions, with the aid of the AC of Riemann–Liouville fD, and the distribution theory in the space D′r,R, which is introduced in this paper, or by the term-by-term inverse Laplace transform of AC of Laplace transform of the solution expressed by a series.

  6. New solutions of Heun's general equation

    Energy Technology Data Exchange (ETDEWEB)

    Ishkhanyan, Artur [Engineering Center of Armenian National Academy of Sciences, Ashtarak (Armenia); Suominen, Kalle-Antti [Helsinki Institute of Physics, PL 64, Helsinki (Finland)

    2003-02-07

    We show that in four particular cases the derivative of the solution of Heun's general equation can be expressed in terms of a solution to another Heun's equation. Starting from this property, we use the Gauss hypergeometric functions to construct series solutions to Heun's equation for the mentioned cases. Each of the hypergeometric functions involved has correct singular behaviour at only one of the singular points of the equation; the sum, however, has correct behaviour. (letter to the editor)

  7. Wave-function functionals for the density

    International Nuclear Information System (INIS)

    Slamet, Marlina; Pan Xiaoyin; Sahni, Viraht

    2011-01-01

    We extend the idea of the constrained-search variational method for the construction of wave-function functionals ψ[χ] of functions χ. The search is constrained to those functions χ such that ψ[χ] reproduces the density ρ(r) while simultaneously leading to an upper bound to the energy. The functionals are thereby normalized and automatically satisfy the electron-nucleus coalescence condition. The functionals ψ[χ] are also constructed to satisfy the electron-electron coalescence condition. The method is applied to the ground state of the helium atom to construct functionals ψ[χ] that reproduce the density as given by the Kinoshita correlated wave function. The expectation of single-particle operators W=Σ i r i n , n=-2,-1,1,2, W=Σ i δ(r i ) are exact, as must be the case. The expectations of the kinetic energy operator W=-(1/2)Σ i ∇ i 2 , the two-particle operators W=Σ n u n , n=-2,-1,1,2, where u=|r i -r j |, and the energy are accurate. We note that the construction of such functionals ψ[χ] is an application of the Levy-Lieb constrained-search definition of density functional theory. It is thereby possible to rigorously determine which functional ψ[χ] is closer to the true wave function.

  8. Nonlocal kinetic energy functionals by functional integration

    Science.gov (United States)

    Mi, Wenhui; Genova, Alessandro; Pavanello, Michele

    2018-05-01

    Since the seminal studies of Thomas and Fermi, researchers in the Density-Functional Theory (DFT) community are searching for accurate electron density functionals. Arguably, the toughest functional to approximate is the noninteracting kinetic energy, Ts[ρ], the subject of this work. The typical paradigm is to first approximate the energy functional and then take its functional derivative, δ/Ts[ρ ] δ ρ (r ) , yielding a potential that can be used in orbital-free DFT or subsystem DFT simulations. Here, this paradigm is challenged by constructing the potential from the second-functional derivative via functional integration. A new nonlocal functional for Ts[ρ] is prescribed [which we dub Mi-Genova-Pavanello (MGP)] having a density independent kernel. MGP is constructed to satisfy three exact conditions: (1) a nonzero "Kinetic electron" arising from a nonzero exchange hole; (2) the second functional derivative must reduce to the inverse Lindhard function in the limit of homogenous densities; (3) the potential is derived from functional integration of the second functional derivative. Pilot calculations show that MGP is capable of reproducing accurate equilibrium volumes, bulk moduli, total energy, and electron densities for metallic (body-centered cubic, face-centered cubic) and semiconducting (crystal diamond) phases of silicon as well as of III-V semiconductors. The MGP functional is found to be numerically stable typically reaching self-consistency within 12 iterations of a truncated Newton minimization algorithm. MGP's computational cost and memory requirements are low and comparable to the Wang-Teter nonlocal functional or any generalized gradient approximation functional.

  9. Generalized Probability Functions

    Directory of Open Access Journals (Sweden)

    Alexandre Souto Martinez

    2009-01-01

    Full Text Available From the integration of nonsymmetrical hyperboles, a one-parameter generalization of the logarithmic function is obtained. Inverting this function, one obtains the generalized exponential function. Motivated by the mathematical curiosity, we show that these generalized functions are suitable to generalize some probability density functions (pdfs. A very reliable rank distribution can be conveniently described by the generalized exponential function. Finally, we turn the attention to the generalization of one- and two-tail stretched exponential functions. We obtain, as particular cases, the generalized error function, the Zipf-Mandelbrot pdf, the generalized Gaussian and Laplace pdf. Their cumulative functions and moments were also obtained analytically.

  10. Functionality and homogeneity.

    NARCIS (Netherlands)

    2011-01-01

    Functionality and homogeneity are two of the five Sustainable Safety principles. The functionality principle aims for roads to have but one exclusive function and distinguishes between traffic function (flow) and access function (residence). The homogeneity principle aims at differences in mass,

  11. Extraocular muscle function testing

    Science.gov (United States)

    ... medlineplus.gov/ency/article/003397.htm Extraocular muscle function testing To use the sharing features on this page, please enable JavaScript. Extraocular muscle function testing examines the function of the eye muscles. ...

  12. Congenital platelet function defects

    Science.gov (United States)

    ... pool disorder; Glanzmann's thrombasthenia; Bernard-Soulier syndrome; Platelet function defects - congenital ... Congenital platelet function defects are bleeding disorders that cause reduced platelet function. Most of the time, people with these disorders have ...

  13. Hepatic (Liver) Function Panel

    Science.gov (United States)

    ... Educators Search English Español Blood Test: Hepatic (Liver) Function Panel KidsHealth / For Parents / Blood Test: Hepatic (Liver) ... kidneys ) is working. What Is a Hepatic (Liver) Function Panel? A liver function panel is a blood ...

  14. Platelet Function Tests

    Science.gov (United States)

    ... Patient Resources For Health Professionals Subscribe Search Platelet Function Tests Send Us Your Feedback Choose Topic At ... Also Known As Platelet Aggregation Studies PFT Platelet Function Assay PFA Formal Name Platelet Function Tests This ...

  15. On Poisson functions

    OpenAIRE

    Terashima, Yuji

    2008-01-01

    In this paper, defining Poisson functions on super manifolds, we show that the graphs of Poisson functions are Dirac structures, and find Poisson functions which include as special cases both quasi-Poisson structures and twisted Poisson structures.

  16. Investigating body function

    International Nuclear Information System (INIS)

    Monks, R.; Riley, A.L.M.

    1981-01-01

    This invention relates to the investigation of body function, especially small bowel function but also liver function, using bile acids and bile salts or their metabolic precursors labelled with radio isotopes and selenium or tellurium. (author)

  17. Analytical solutions to orthotropic variable thickness disk problems

    Directory of Open Access Journals (Sweden)

    Ahmet N. ERASLAN

    2016-02-01

    Full Text Available An analytical model is developed to estimate the mechanical response of nonisothermal, orthotropic, variable thickness disks under a variety of boundary conditions. Combining basic mechanical equations of disk geometry with the equations of orthotropic material, the elastic equation of the disk is obtained. This equation is transformed into a standard hypergeometric differential equation by means of a suitable transformation. An analytical solution is then obtained in terms of hypergeometric functions. The boundary conditions used to complete the solutions simulate rotating annular disks with two free surfaces, stationary annular disks with pressurized inner and free outer surfaces, and free inner and pressurized outer surfaces. The results of the solutions to each of these cases are presented in graphical forms. It is observed that, for the three cases investigated the elastic orthotropy parameter turns out to be an important parameter affecting the elastic behaviorKeywords: Orthotropic disk, Variable thickness, Thermoelasticity, Hypergeometric equation

  18. Functional bowel disorders and functional abdominal pain

    OpenAIRE

    Thompson, W; Longstreth, G; Drossman, D; Heaton, K; Irvine, E; Muller-Lissner, S

    1999-01-01

    The Rome diagnostic criteria for the functional bowel disorders and functional abdominal pain are used widely in research and practice. A committee consensus approach, including criticism from multinational expert reviewers, was used to revise the diagnostic criteria and update diagnosis and treatment recommendations, based on research results. The terminology was clarified and the diagnostic criteria and management recommendations were revised. A functional bowel disorder (FBD) is diagnosed ...

  19. Functional microorganisms for functional food quality.

    Science.gov (United States)

    Gobbetti, M; Cagno, R Di; De Angelis, M

    2010-09-01

    Functional microorganisms and health benefits represent a binomial with great potential for fermented functional foods. The health benefits of fermented functional foods are expressed either directly through the interactions of ingested live microorganisms with the host (probiotic effect) or indirectly as the result of the ingestion of microbial metabolites synthesized during fermentation (biogenic effect). Since the importance of high viability for probiotic effect, two major options are currently pursued for improving it--to enhance bacterial stress response and to use alternative products for incorporating probiotics (e.g., ice cream, cheeses, cereals, fruit juices, vegetables, and soy beans). Further, it seems that quorum sensing signal molecules released by probiotics may interact with human epithelial cells from intestine thus modulating several physiological functions. Under optimal processing conditions, functional microorganisms contribute to food functionality through their enzyme portfolio and the release of metabolites. Overproduction of free amino acids and vitamins are two classical examples. Besides, bioactive compounds (e.g., peptides, γ-amino butyric acid, and conjugated linoleic acid) may be released during food processing above the physiological threshold and they may exert various in vivo health benefits. Functional microorganisms are even more used in novel strategies for decreasing phenomenon of food intolerance (e.g., gluten intolerance) and allergy. By a critical approach, this review will aim at showing the potential of functional microorganisms for the quality of functional foods.

  20. The Interpretive Function

    DEFF Research Database (Denmark)

    Agerbo, Heidi

    2017-01-01

    Approximately a decade ago, it was suggested that a new function should be added to the lexicographical function theory: the interpretive function(1). However, hardly any research has been conducted into this function, and though it was only suggested that this new function was relevant...... to incorporate into lexicographical theory, some scholars have since then assumed that this function exists(2), including the author of this contribution. In Agerbo (2016), I present arguments supporting the incorporation of the interpretive function into the function theory and suggest how non-linguistic signs...... can be treated in specific dictionary articles. However, in the current article, due to the results of recent research, I argue that the interpretive function should not be considered an individual main function. The interpretive function, contrary to some of its definitions, is not connected...

  1. Asymptotic iteration method for the modified Pöschl–Teller potential ...

    Indian Academy of Sciences (India)

    2017-01-04

    Jan 4, 2017 ... Relativistic energy equation is calculated numerically by the Matlab soft- ware. The increase in the radial quantum number nr causes a decrease in the energy value, and the wave functions of the radial and the angular parts are expressed in terms of hypergeometric functions. Some thermodynamical.

  2. Asymptotic iteration method for the modified Pöschl–Teller potential ...

    Indian Academy of Sciences (India)

    Relativistic energy equation is calculated numerically by the Matlab software. The increase in the radial quantum number nr causes a decrease in the energy value, and the wave functions of the radial and the angular parts are expressed in terms of hypergeometric functions. Some thermodynamical properties of the system ...

  3. Differential Equations Compatible with KZ Equations

    International Nuclear Information System (INIS)

    Felder, G.; Markov, Y.; Tarasov, V.; Varchenko, A.

    2000-01-01

    We define a system of 'dynamical' differential equations compatible with the KZ differential equations. The KZ differential equations are associated to a complex simple Lie algebra g. These are equations on a function of n complex variables z i taking values in the tensor product of n finite dimensional g-modules. The KZ equations depend on the 'dual' variable in the Cartan subalgebra of g. The dynamical differential equations are differential equations with respect to the dual variable. We prove that the standard hypergeometric solutions of the KZ equations also satisfy the dynamical equations. As an application we give a new determinant formula for the coordinates of a basis of hypergeometric solutions

  4. Every storage function is a state function

    NARCIS (Netherlands)

    Trentelman, H.L.; Willems, J.C.

    1997-01-01

    It is shown that for linear dynamical systems with quadratic supply rates, a storage function can always be written as a quadratic function of the state of an associated linear dynamical system. This dynamical system is obtained by combining the dynamics of the original system with the dynamics of

  5. Persistent Functional Languages: Toward Functional Relational Databases

    NARCIS (Netherlands)

    Wevers, L.

    2014-01-01

    Functional languages provide new approaches to concurrency control, based on techniques such as lazy evaluation and memoization. We have designed and implemented a persistent functional language based on these ideas, which we plan to use for the implementation of a relational database system. With

  6. Museums and Their Functions.

    Science.gov (United States)

    Osborne, Harold

    1985-01-01

    Historical background concerning the nature and function of museums is provided, and the aesthetic functions of museums are discussed. The first major aesthetic function of museums is to preserve the artistic heritage of mankind and to make it widely available. The second major function is patronage. (RM)

  7. Hierarchical wave functions revisited

    International Nuclear Information System (INIS)

    Li Dingping.

    1997-11-01

    We study the hierarchical wave functions on a sphere and on a torus. We simplify some wave functions on a sphere or a torus using the analytic properties of wave functions. The open question, the construction of the wave function for quasi electron excitation on a torus, is also solved in this paper. (author)

  8. Functional Programming in R

    DEFF Research Database (Denmark)

    Mailund, Thomas

    Master functions and discover how to write functional programs in R. In this book, you'll make your functions pure by avoiding side-effects; you’ll write functions that manipulate other functions, and you’ll construct complex functions using simpler functions as building blocks. In Functional...... Programming in R, you’ll see how we can replace loops, which can have side-effects, with recursive functions that can more easily avoid them. In addition, the book covers why you shouldn't use recursion when loops are more efficient and how you can get the best of both worlds. Functional programming...... is a style of programming, like object-oriented programming, but one that focuses on data transformations and calculations rather than objects and state. Where in object-oriented programming you model your programs by describing which states an object can be in and how methods will reveal or modify...

  9. Functional Programming in R

    DEFF Research Database (Denmark)

    Mailund, Thomas

    2017-01-01

    Master functions and discover how to write functional programs in R. In this book, you'll make your functions pure by avoiding side-effects; you’ll write functions that manipulate other functions, and you’ll construct complex functions using simpler functions as building blocks. In Functional...... Programming in R, you’ll see how we can replace loops, which can have side-effects, with recursive functions that can more easily avoid them. In addition, the book covers why you shouldn't use recursion when loops are more efficient and how you can get the best of both worlds. Functional programming...... is a style of programming, like object-oriented programming, but one that focuses on data transformations and calculations rather than objects and state. Where in object-oriented programming you model your programs by describing which states an object can be in and how methods will reveal or modify...

  10. Teager Correlation Function

    DEFF Research Database (Denmark)

    Bysted, Tommy Kristensen; Hamila, R.; Gabbouj, M.

    1998-01-01

    A new correlation function called the Teager correlation function is introduced in this paper. The connection between this function, the Teager energy operator and the conventional correlation function is established. Two applications are presented. The first is the minimization of the Teager error...... norm and the second one is the use of the instantaneous Teager correlation function for simultaneous estimation of TDOA and FDOA (Time and Frequency Difference of Arrivals)....

  11. Properties of Ambiguity Functions

    OpenAIRE

    Mulcahy-Stanislawczyk, John

    2014-01-01

    The use of ambiguity functions in radar signal design and analysis is very common. Understanding the various properties and meanings of ambiguity functions allow a signal designer to understand the time delay and doppler shift properties of a given signal. Through the years, several different versions of the ambiguity function have been used. Each of these functions essentially have the same physical meaning; however, the use of different functions makes it difficult to be sure that certai...

  12. Ergotic / epistemic / semiotic functions

    OpenAIRE

    Luciani , Annie

    2007-01-01

    International audience; Claude Cadoz has introduced a typology of human-environment relation, identifying three functions. This typology allows characterizing univocally, i.e. in a non-redundant manner, the computer devices and interfaces that allow human to interact with environment through and by computers. These three functions are: the epistemic function, the semiotic function, the ergotic function. Conversely to the terms epistemic and semiotic that are usual, the term ergotic has been s...

  13. Variational functionals which admit discontinuous trial functions

    International Nuclear Information System (INIS)

    Nelson, P. Jr.

    1975-01-01

    It is argued that variational synthesis with discontinuous trial functions requires variational principles applicable to equations involving operators acting between distinct Hilbert spaces. A description is given of a Roussopoulos-type variational principle generalized to cover this situation. This principle is suggested as the basis for a unified approach to the derivation of variational functionals. In addition to esthetics, this approach has the advantage that the mathematical details increase the understanding of the derived functional, particularly the sense in which a synthesized solution should be regarded as an approximation to the true solution. By way of illustration, the generalized Roussopoulos principle is applied to derive a class of first-order diffusion functionals which admit trial functions containing approximations at an interface. These ''asymptotic'' interface quantities are independent of the limiting approximations from either side and permit use of different trial spectra at and on either side of an interface. The class of functionals derived contains as special cases both the Lagrange multiplier method of Buslik and two functionals of Lambropoulos and Luco. Some numerical results for a simple two-group model confirm that the ''multipliers'' can closely approximate the appropriate quantity in the region near an interface. (U.S.)

  14. A Blue Lagoon Function

    DEFF Research Database (Denmark)

    Markvorsen, Steen

    2007-01-01

    We consider a specific function of two variables whose graph surface resembles a blue lagoon. The function has a saddle point $p$, but when the function is restricted to any given straight line through $p$ it has a {\\em{strict local minimum}} along that line at $p$.......We consider a specific function of two variables whose graph surface resembles a blue lagoon. The function has a saddle point $p$, but when the function is restricted to any given straight line through $p$ it has a {\\em{strict local minimum}} along that line at $p$....

  15. Quality function deployment

    International Nuclear Information System (INIS)

    1981-10-01

    This book indicates quality function deployment with quality and deployment of quality function, process and prospect of quality function deployment and development, product process and conception of quality table, deployment of quality demand, design of quality table and application of concurrent multi design, progress design and quality development, main safe part and management of important function part, quality development and deployment of method of construction, quality deployment and economics, total system of quality function deployment and task of quality function deployment in the present and future.

  16. Functional Object Analysis

    DEFF Research Database (Denmark)

    Raket, Lars Lau

    We propose a direction it the field of statistics which we will call functional object analysis. This subfields considers the analysis of functional objects defined on continuous domains. In this setting we will focus on model-based statistics, with a particularly emphasis on mixed......-effect formulations, where the observed functional signal is assumed to consist of both fixed and random functional effects. This thesis takes the initial steps toward the development of likelihood-based methodology for functional objects. We first consider analysis of functional data defined on high...

  17. High spin structure functions

    International Nuclear Information System (INIS)

    Khan, H.

    1990-01-01

    This thesis explores deep inelastic scattering of a lepton beam from a polarized nuclear target with spin J=1. After reviewing the formation for spin-1/2, the structure functions for a spin-1 target are defined in terms of the helicity amplitudes for forward compton scattering. A version of the convolution model, which incorporates relativistic and binding energy corrections is used to calculate the structure functions of a neutron target. A simple parameterization of these structure functions is given in terms of a few neutron wave function parameters and the free nucleon structure functions. This allows for an easy comparison of structure functions calculated using different neutron models. (author)

  18. From functional architecture to functional connectomics.

    Science.gov (United States)

    Reid, R Clay

    2012-07-26

    "Receptive Fields, Binocular Interaction and Functional Architecture in the Cat's Visual Cortex" by Hubel and Wiesel (1962) reported several important discoveries: orientation columns, the distinct structures of simple and complex receptive fields, and binocular integration. But perhaps the paper's greatest influence came from the concept of functional architecture (the complex relationship between in vivo physiology and the spatial arrangement of neurons) and several models of functionally specific connectivity. They thus identified two distinct concepts, topographic specificity and functional specificity, which together with cell-type specificity constitute the major determinants of nonrandom cortical connectivity. Orientation columns are iconic examples of topographic specificity, whereby axons within a column connect with cells of a single orientation preference. Hubel and Wiesel also saw the need for functional specificity at a finer scale in their model of thalamic inputs to simple cells, verified in the 1990s. The difficult but potentially more important question of functional specificity between cortical neurons is only now becoming tractable with new experimental techniques. Copyright © 2012 Elsevier Inc. All rights reserved.

  19. Functional Median Polish

    KAUST Repository

    Sun, Ying

    2012-08-03

    This article proposes functional median polish, an extension of univariate median polish, for one-way and two-way functional analysis of variance (ANOVA). The functional median polish estimates the functional grand effect and functional main factor effects based on functional medians in an additive functional ANOVA model assuming no interaction among factors. A functional rank test is used to assess whether the functional main factor effects are significant. The robustness of the functional median polish is demonstrated by comparing its performance with the traditional functional ANOVA fitted by means under different outlier models in simulation studies. The functional median polish is illustrated on various applications in climate science, including one-way and two-way ANOVA when functional data are either curves or images. Specifically, Canadian temperature data, U. S. precipitation observations and outputs of global and regional climate models are considered, which can facilitate the research on the close link between local climate and the occurrence or severity of some diseases and other threats to human health. © 2012 International Biometric Society.

  20. Operations Between Functions

    DEFF Research Database (Denmark)

    Gardner, Richard J.; Kiderlen, Markus

    A structural theory of operations between real-valued (or extended-real-valued) functions on a nonempty subset A of Rn is initiated. It is shown, for example, that any operation ∗ on a cone of functions containing the constant functions, which is pointwise, positively homogeneous, monotonic......, and associative, must be one of 40 explicitly given types. In particular, this is the case for operations between pairs of arbitrary, or continuous, or differentiable functions. The term pointwise means that (f ∗g)(x) = F(f(x), g(x)), for all x ∈ A and some function F of two variables. Several results in the same...... spirit are obtained for operations between convex functions or between support functions. For example, it is shown that ordinary addition is the unique pointwise operation between convex functions satisfying the identity property, i.e., f ∗ 0 = 0 ∗ f = f, for all convex f, while other results classify Lp...

  1. Kidney function tests

    Science.gov (United States)

    Kidney function tests are common lab tests used to evaluate how well the kidneys are working. Such tests include: ... Oh MS, Briefel G. Evaluation of renal function, water, electrolytes ... and Management by Laboratory Methods . 23rd ed. Philadelphia, ...

  2. Liver Function Tests

    Science.gov (United States)

    ... digest food, store energy, and remove poisons. Liver function tests are blood tests that check to see ... as hepatitis and cirrhosis. You may have liver function tests as part of a regular checkup. Or ...

  3. Functionalized diamond nanoparticles

    KAUST Repository

    Beaujuge, Pierre M.; El Tall, Omar; Raja, Inam U.

    2014-01-01

    A diamond nanoparticle can be functionalized with a substituted dienophile under ambient conditions, and in the absence of catalysts or additional reagents. The functionalization is thought to proceed through an addition reaction.

  4. Smart hydrogel functional materials

    CERN Document Server

    Chu, Liang-Yin; Ju, Xiao-Jie

    2014-01-01

    This book systematically introduces smart hydrogel functional materials with the configurations ranging from hydrogels to microgels. It serves as an excellent reference for designing and fabricating artificial smart hydrogel functional materials.

  5. Integrals of Bessel functions

    OpenAIRE

    Babusci, D.; Dattoli, G.; Germano, B.; Martinelli, M. R.; Ricci, P. E.

    2011-01-01

    We use the operator method to evaluate a class of integrals involving Bessel or Bessel-type functions. The technique we propose is based on the formal reduction of these family of functions to Gaussians.

  6. Functional Python programming

    CERN Document Server

    Lott, Steven

    2015-01-01

    This book is for developers who want to use Python to write programs that lean heavily on functional programming design patterns. You should be comfortable with Python programming, but no knowledge of functional programming paradigms is needed.

  7. Functionalized diamond nanoparticles

    KAUST Repository

    Beaujuge, Pierre M.

    2014-10-21

    A diamond nanoparticle can be functionalized with a substituted dienophile under ambient conditions, and in the absence of catalysts or additional reagents. The functionalization is thought to proceed through an addition reaction.

  8. Ecological Functions of Landscapes

    Science.gov (United States)

    Kiryushin, V. I.

    2018-01-01

    Ecological functions of landscapes are considered a system of processes ensuring the development, preservation, and evolution of ecosystems and the biosphere as a whole. The concept of biogeocenosis can be considered a model that integrates biotic and environmental functions. The most general biogeocenotic functions specify the biodiversity, biotic links, self-organization, and evolution of ecosystems. Close interaction between biocenosis and the biotope (ecotope) is ensured by the continuous exchange of matter, energy, and information. Ecotope determines the biocenosis. The group of ecotopic functions includes atmospheric (gas exchange, heat exchange, hydroatmospheric, climate-forming), lithospheric (geodynamic, geophysical, and geochemical), hydrologic and hydrogeologic functions of landscape and ecotopic functions of soils. Bioecological functions emerge as a result of the biotope and ecotope interaction; these are the bioproductive, destructive, organoaccumulative, biochemical (gas, concentration, redox, biochemical, biopedological), pedogenetic, and energy functions

  9. Functional Median Polish

    KAUST Repository

    Sun, Ying; Genton, Marc G.

    2012-01-01

    polish is demonstrated by comparing its performance with the traditional functional ANOVA fitted by means under different outlier models in simulation studies. The functional median polish is illustrated on various applications in climate science

  10. Hybrid functional pseudopotentials

    Science.gov (United States)

    Yang, Jing; Tan, Liang Z.; Rappe, Andrew M.

    2018-02-01

    The consistency between the exchange-correlation functional used in pseudopotential construction and in the actual density functional theory calculation is essential for the accurate prediction of fundamental properties of materials. However, routine hybrid density functional calculations at present still rely on generalized gradient approximation pseudopotentials due to the lack of hybrid functional pseudopotentials. Here, we present a scheme for generating hybrid functional pseudopotentials, and we analyze the importance of pseudopotential density functional consistency for hybrid functionals. For the PBE0 hybrid functional, we benchmark our pseudopotentials for structural parameters and fundamental electronic gaps of the Gaussian-2 (G2) molecular dataset and some simple solids. Our results show that using our PBE0 pseudopotentials in PBE0 calculations improves agreement with respect to all-electron calculations.

  11. Photon structure function - theory

    International Nuclear Information System (INIS)

    Bardeen, W.A.

    1984-12-01

    The theoretical status of the photon structure function is reviewed. Particular attention is paid to the hadronic mixing problem and the ability of perturbative QCD to make definitive predictions for the photon structure function. 11 references

  12. Monotone Boolean functions

    International Nuclear Information System (INIS)

    Korshunov, A D

    2003-01-01

    Monotone Boolean functions are an important object in discrete mathematics and mathematical cybernetics. Topics related to these functions have been actively studied for several decades. Many results have been obtained, and many papers published. However, until now there has been no sufficiently complete monograph or survey of results of investigations concerning monotone Boolean functions. The object of this survey is to present the main results on monotone Boolean functions obtained during the last 50 years

  13. and chebyshev functions

    Directory of Open Access Journals (Sweden)

    Mohsen Razzaghi

    2000-01-01

    Full Text Available A direct method for finding the solution of variational problems using a hybrid function is discussed. The hybrid functions which consist of block-pulse functions plus Chebyshev polynomials are introduced. An operational matrix of integration and the integration of the cross product of two hybrid function vectors are presented and are utilized to reduce a variational problem to the solution of an algebraic equation. Illustrative examples are included to demonstrate the validity and applicability of the technique.

  14. Functional Task Test (FTT)

    Science.gov (United States)

    Bloomberg, Jacob J.; Mulavara, Ajitkumar; Peters, Brian T.; Rescheke, Millard F.; Wood, Scott; Lawrence, Emily; Koffman, Igor; Ploutz-Snyder, Lori; Spiering, Barry A.; Feeback, Daniel L.; hide

    2009-01-01

    This slide presentation reviews the Functional Task Test (FTT), an interdisciplinary testing regimen that has been developed to evaluate astronaut postflight functional performance and related physiological changes. The objectives of the project are: (1) to develop a set of functional tasks that represent critical mission tasks for the Constellation Program, (2) determine the ability to perform these tasks after space flight, (3) Identify the key physiological factors that contribute to functional decrements and (4) Use this information to develop targeted countermeasures.

  15. Pseudolinear functions and optimization

    CERN Document Server

    Mishra, Shashi Kant

    2015-01-01

    Pseudolinear Functions and Optimization is the first book to focus exclusively on pseudolinear functions, a class of generalized convex functions. It discusses the properties, characterizations, and applications of pseudolinear functions in nonlinear optimization problems.The book describes the characterizations of solution sets of various optimization problems. It examines multiobjective pseudolinear, multiobjective fractional pseudolinear, static minmax pseudolinear, and static minmax fractional pseudolinear optimization problems and their results. The authors extend these results to locally

  16. Photon wave function

    OpenAIRE

    Bialynicki-Birula, Iwo

    2005-01-01

    Photon wave function is a controversial concept. Controversies stem from the fact that photon wave functions can not have all the properties of the Schroedinger wave functions of nonrelativistic wave mechanics. Insistence on those properties that, owing to peculiarities of photon dynamics, cannot be rendered, led some physicists to the extreme opinion that the photon wave function does not exist. I reject such a fundamentalist point of view in favor of a more pragmatic approach. In my view, t...

  17. On Functional Calculus Estimates

    NARCIS (Netherlands)

    Schwenninger, F.L.

    2015-01-01

    This thesis presents various results within the field of operator theory that are formulated in estimates for functional calculi. Functional calculus is the general concept of defining operators of the form $f(A)$, where f is a function and $A$ is an operator, typically on a Banach space. Norm

  18. Phylogenetic molecular function annotation

    International Nuclear Information System (INIS)

    Engelhardt, Barbara E; Jordan, Michael I; Repo, Susanna T; Brenner, Steven E

    2009-01-01

    It is now easier to discover thousands of protein sequences in a new microbial genome than it is to biochemically characterize the specific activity of a single protein of unknown function. The molecular functions of protein sequences have typically been predicted using homology-based computational methods, which rely on the principle that homologous proteins share a similar function. However, some protein families include groups of proteins with different molecular functions. A phylogenetic approach for predicting molecular function (sometimes called 'phylogenomics') is an effective means to predict protein molecular function. These methods incorporate functional evidence from all members of a family that have functional characterizations using the evolutionary history of the protein family to make robust predictions for the uncharacterized proteins. However, they are often difficult to apply on a genome-wide scale because of the time-consuming step of reconstructing the phylogenies of each protein to be annotated. Our automated approach for function annotation using phylogeny, the SIFTER (Statistical Inference of Function Through Evolutionary Relationships) methodology, uses a statistical graphical model to compute the probabilities of molecular functions for unannotated proteins. Our benchmark tests showed that SIFTER provides accurate functional predictions on various protein families, outperforming other available methods.

  19. New Similarity Functions

    DEFF Research Database (Denmark)

    Yazdani, Hossein; Ortiz-Arroyo, Daniel; Kwasnicka, Halina

    2016-01-01

    spaces, in addition to their similarity in the vector space. Prioritized Weighted Feature Distance (PWFD) works similarly as WFD, but provides the ability to give priorities to desirable features. The accuracy of the proposed functions are compared with other similarity functions on several data sets....... Our results show that the proposed functions work better than other methods proposed in the literature....

  20. Two Functions of Language

    Science.gov (United States)

    Feldman, Carol Fleisher

    1977-01-01

    Author advocates the view that meaning is necessarily dependent upon the communicative function of language and examines the objections, particularly those of Noam Chomsky, to this view. Argues that while Chomsky disagrees with the idea that communication is the essential function of language, he implicitly agrees that it has a function.…

  1. Automatic differentiation of functions

    International Nuclear Information System (INIS)

    Douglas, S.R.

    1990-06-01

    Automatic differentiation is a method of computing derivatives of functions to any order in any number of variables. The functions must be expressible as combinations of elementary functions. When evaluated at specific numerical points, the derivatives have no truncation error and are automatically found. The method is illustrated by simple examples. Source code in FORTRAN is provided

  2. Nonparametric Transfer Function Models

    Science.gov (United States)

    Liu, Jun M.; Chen, Rong; Yao, Qiwei

    2009-01-01

    In this paper a class of nonparametric transfer function models is proposed to model nonlinear relationships between ‘input’ and ‘output’ time series. The transfer function is smooth with unknown functional forms, and the noise is assumed to be a stationary autoregressive-moving average (ARMA) process. The nonparametric transfer function is estimated jointly with the ARMA parameters. By modeling the correlation in the noise, the transfer function can be estimated more efficiently. The parsimonious ARMA structure improves the estimation efficiency in finite samples. The asymptotic properties of the estimators are investigated. The finite-sample properties are illustrated through simulations and one empirical example. PMID:20628584

  3. Weakly clopen functions

    International Nuclear Information System (INIS)

    Son, Mi Jung; Park, Jin Han; Lim, Ki Moon

    2007-01-01

    We introduce a new class of functions called weakly clopen function which includes the class of almost clopen functions due to Ekici [Ekici E. Generalization of perfectly continuous, regular set-connected and clopen functions. Acta Math Hungar 2005;107:193-206] and is included in the class of weakly continuous functions due to Levine [Levine N. A decomposition of continuity in topological spaces. Am Math Mon 1961;68:44-6]. Some characterizations and several properties concerning weakly clopenness are obtained. Furthermore, relationships among weak clopenness, almost clopenness, clopenness and weak continuity are investigated

  4. Implementing function spreadsheets

    DEFF Research Database (Denmark)

    Sestoft, Peter

    2008-01-01

    : that of turning an expression into a named function. Hence they proposed a way to define a function in terms of a worksheet with designated input and output cells; we shall call it a function sheet. The goal of our work is to develop implementations of function sheets and study their application to realistic...... examples. Therefore, we are also developing a simple yet comprehensive spreadsheet core implementation for experimentation with this technology. Here we report briefly on our experiments with function sheets as well as other uses of our spreadsheet core implementation....

  5. Transfer function combinations

    KAUST Repository

    Zhou, Liang; Schott, Mathias; Hansen, Charles

    2012-01-01

    Direct volume rendering has been an active area of research for over two decades. Transfer function design remains a difficult task since current methods, such as traditional 1D and 2D transfer functions, are not always effective for all data sets. Various 1D or 2D transfer function spaces have been proposed to improve classification exploiting different aspects, such as using the gradient magnitude for boundary location and statistical, occlusion, or size metrics. In this paper, we present a novel transfer function method which can provide more specificity for data classification by combining different transfer function spaces. In this work, a 2D transfer function can be combined with 1D transfer functions which improve the classification. Specifically, we use the traditional 2D scalar/gradient magnitude, 2D statistical, and 2D occlusion spectrum transfer functions and combine these with occlusion and/or size-based transfer functions to provide better specificity. We demonstrate the usefulness of the new method by comparing to the following previous techniques: 2D gradient magnitude, 2D occlusion spectrum, 2D statistical transfer functions and 2D size based transfer functions. © 2012 Elsevier Ltd.

  6. Transfer function combinations

    KAUST Repository

    Zhou, Liang

    2012-10-01

    Direct volume rendering has been an active area of research for over two decades. Transfer function design remains a difficult task since current methods, such as traditional 1D and 2D transfer functions, are not always effective for all data sets. Various 1D or 2D transfer function spaces have been proposed to improve classification exploiting different aspects, such as using the gradient magnitude for boundary location and statistical, occlusion, or size metrics. In this paper, we present a novel transfer function method which can provide more specificity for data classification by combining different transfer function spaces. In this work, a 2D transfer function can be combined with 1D transfer functions which improve the classification. Specifically, we use the traditional 2D scalar/gradient magnitude, 2D statistical, and 2D occlusion spectrum transfer functions and combine these with occlusion and/or size-based transfer functions to provide better specificity. We demonstrate the usefulness of the new method by comparing to the following previous techniques: 2D gradient magnitude, 2D occlusion spectrum, 2D statistical transfer functions and 2D size based transfer functions. © 2012 Elsevier Ltd.

  7. Functional Maximum Autocorrelation Factors

    DEFF Research Database (Denmark)

    Larsen, Rasmus; Nielsen, Allan Aasbjerg

    2005-01-01

    MAF outperforms the functional PCA in concentrating the interesting' spectra/shape variation in one end of the eigenvalue spectrum and allows for easier interpretation of effects. Conclusions. Functional MAF analysis is a useful methods for extracting low dimensional models of temporally or spatially......Purpose. We aim at data where samples of an underlying function are observed in a spatial or temporal layout. Examples of underlying functions are reflectance spectra and biological shapes. We apply functional models based on smoothing splines and generalize the functional PCA in......\\verb+~+\\$\\backslash\\$cite{ramsay97} to functional maximum autocorrelation factors (MAF)\\verb+~+\\$\\backslash\\$cite{switzer85,larsen2001d}. We apply the method to biological shapes as well as reflectance spectra. {\\$\\backslash\\$bf Methods}. MAF seeks linear combination of the original variables that maximize autocorrelation between...

  8. Relativistic Treatment of Spinless Particles Subject to a Tietz-Wei Oscillator

    Institute of Scientific and Technical Information of China (English)

    孙国华; 董世海

    2012-01-01

    The bound state solutions of the relativistic Klein-Gordon equation with the Tietz-Wei diatomic molecular potential are presented for the s wave. It is shown that the solutions can be expressed by the generalized hypergeometric functions. The normalized wavefunctions are also derived.

  9. Analytical Solution of the Schrödinger Equation with Spatially Varying Effective Mass for Generalised Hylleraas Potential

    International Nuclear Information System (INIS)

    Debnath, S.; Maji, Smarajit; Meyur, Sanjib

    2014-01-01

    We have obtained exact solution of the effective mass Schrödinger equation for the generalised Hylleraas potential. The exact bound state energy eigenvalues and corresponding eigenfunctions are presented. The bound state eigenfunctions are obtained in terms of the hypergeometric functions. Results are also given for the special case of potential parameter.

  10. Approximate Eigensolutions of the Deformed Woods—Saxon Potential via AIM

    International Nuclear Information System (INIS)

    Ikhdair, Sameer M.; Falaye Babatunde, J.; Hamzavi, Majid

    2013-01-01

    Using the Pekeris approximation, the Schrödinger equation is solved for the nuclear deformed Woods—Saxon potential within the framework of the asymptotic iteration method. The energy levels are worked out and the corresponding normalized eigenfunctions are obtained in terms of hypergeometric function

  11. Glauber amplitudes for transitions from low lying states in hydrogen atom by charged particle impact

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, S; Srivastava, M K [Roorkee Univ. (India). Dept. of Physics

    1977-07-01

    The Glauber amplitudes for the general transition nlm ..-->.. n'1'm' in charged particle - hydrogen atom collisions have been obtained in the form of a one-dimensional integral. The final expression involves only a few hypergeometric functions if n is not too large and is particularly suited to study excitation to highly excited states from a low lying state.

  12. On Analytic Solution of resonant Mixing for Solar Neutrino Oscillations

    OpenAIRE

    Masatoshi, ITO; Takao, KANEKO; Masami, NAKAGAWA; Department of Physics, Meijo University; Department of Physics, Meijo University; Department of Physics, Meijo University

    1988-01-01

    Behavior of resonant mixing in matter-enhancing region for solar neutrino oscillation, the Mikheyev-Smirnov-Wolfenstein mechanism, is reanalyzed by means of an analytic treatment recently proposed. We give solutions in terms of confluent hypergeometric functions, which agree with "exact" solutions of coupled differential equations.

  13. On computing ellipsoidal harmonics using Jekeli's renormalization

    Czech Academy of Sciences Publication Activity Database

    Sebera, Josef; Bouman, J.; Bosch, W.

    2012-01-01

    Roč. 86, č. 9 (2012), s. 713-726 ISSN 0949-7714 Institutional support: RVO:67985815 Keywords : Earth's gravitational field * spherical and ellipsoidal harmonics * hypergeometric function Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 2.808, year: 2012

  14. E-Orbit Functions

    Directory of Open Access Journals (Sweden)

    Jiri Patera

    2008-01-01

    Full Text Available We review and further develop the theory of $E$-orbit functions. They are functions on the Euclidean space $E_n$ obtained from the multivariate exponential function by symmetrization by means of an even part $W_{e}$ of a Weyl group $W$, corresponding to a Coxeter-Dynkin diagram. Properties of such functions are described. They are closely related to symmetric and antisymmetric orbit functions which are received from exponential functions by symmetrization and antisymmetrization procedure by means of a Weyl group $W$. The $E$-orbit functions, determined by integral parameters, are invariant withrespect to even part $W^{aff}_{e}$ of the affine Weyl group corresponding to $W$. The $E$-orbit functions determine a symmetrized Fourier transform, where these functions serve as a kernel of the transform. They also determine a transform on a finite set of points of the fundamental domain $F^{e}$ of the group $W^{aff}_{e}$ (the discrete $E$-orbit function transform.

  15. Antisymmetric Orbit Functions

    Directory of Open Access Journals (Sweden)

    Anatoliy Klimyk

    2007-02-01

    Full Text Available In the paper, properties of antisymmetric orbit functions are reviewed and further developed. Antisymmetric orbit functions on the Euclidean space $E_n$ are antisymmetrized exponential functions. Antisymmetrization is fulfilled by a Weyl group, corresponding to a Coxeter-Dynkin diagram. Properties of such functions are described. These functions are closely related to irreducible characters of a compact semisimple Lie group $G$ of rank $n$. Up to a sign, values of antisymmetric orbit functions are repeated on copies of the fundamental domain $F$ of the affine Weyl group (determined by the initial Weyl group in the entire Euclidean space $E_n$. Antisymmetric orbit functions are solutions of the corresponding Laplace equation in $E_n$, vanishing on the boundary of the fundamental domain $F$. Antisymmetric orbit functions determine a so-called antisymmetrized Fourier transform which is closely related to expansions of central functions in characters of irreducible representations of the group $G$. They also determine a transform on a finite set of points of $F$ (the discrete antisymmetric orbit function transform. Symmetric and antisymmetric multivariate exponential, sine and cosine discrete transforms are given.

  16. B Plant function analysis report

    International Nuclear Information System (INIS)

    Lund, D.P.

    1995-09-01

    The document contains the functions, function definitions, function interfaces, function interface definitions, Input Computer Automated Manufacturing Definition (IDEFO) diagrams, and a function hierarchy chart that describe what needs to be performed to deactivate B Plant

  17. Rδ-Supercontinuous Functions

    Directory of Open Access Journals (Sweden)

    Kohli J. K.

    2014-06-01

    Full Text Available A new class of functions called ‘Rδ-supercontinuous functions’ is introduced. Their basic properties are studied and their place in the hierarchy of strong variants of continuity which already exist in the literature is elaborated. The class of Rδ-supercontinuous functions (Math. Bohem., to appear properly contains the class of Rz-supercontinuous functions which in its turn properly contains the class of Rcl- supercontinuous functions (Demonstratio Math. 46(1 (2013, 229-244 and so includes all Rcl-supercontinuous (≡clopen continuous functions (Applied Gen. Topol. 8(2 (2007, 293-300; Indian J. Pure Appl. Math. 14(6 (1983, 767-772 and is properly contained in the class of R-supercontinuous functions (Demonstratio Math. 43(3 (2010, 703-723.

  18. Intrinsic-density functionals

    International Nuclear Information System (INIS)

    Engel, J.

    2007-01-01

    The Hohenberg-Kohn theorem and Kohn-Sham procedure are extended to functionals of the localized intrinsic density of a self-bound system such as a nucleus. After defining the intrinsic-density functional, we modify the usual Kohn-Sham procedure slightly to evaluate the mean-field approximation to the functional, and carefully describe the construction of the leading corrections for a system of fermions in one dimension with a spin-degeneracy equal to the number of particles N. Despite the fact that the corrections are complicated and nonlocal, we are able to construct a local Skyrme-like intrinsic-density functional that, while different from the exact functional, shares with it a minimum value equal to the exact ground-state energy at the exact ground-state intrinsic density, to next-to-leading order in 1/N. We briefly discuss implications for real Skyrme functionals

  19. Functional analysis and applications

    CERN Document Server

    Siddiqi, Abul Hasan

    2018-01-01

    This self-contained textbook discusses all major topics in functional analysis. Combining classical materials with new methods, it supplies numerous relevant solved examples and problems and discusses the applications of functional analysis in diverse fields. The book is unique in its scope, and a variety of applications of functional analysis and operator-theoretic methods are devoted to each area of application. Each chapter includes a set of problems, some of which are routine and elementary, and some of which are more advanced. The book is primarily intended as a textbook for graduate and advanced undergraduate students in applied mathematics and engineering. It offers several attractive features making it ideally suited for courses on functional analysis intended to provide a basic introduction to the subject and the impact of functional analysis on applied and computational mathematics, nonlinear functional analysis and optimization. It introduces emerging topics like wavelets, Gabor system, inverse pro...

  20. Counting with symmetric functions

    CERN Document Server

    Mendes, Anthony

    2015-01-01

    This monograph provides a self-contained introduction to symmetric functions and their use in enumerative combinatorics.  It is the first book to explore many of the methods and results that the authors present. Numerous exercises are included throughout, along with full solutions, to illustrate concepts and also highlight many interesting mathematical ideas. The text begins by introducing fundamental combinatorial objects such as permutations and integer partitions, as well as generating functions.  Symmetric functions are considered in the next chapter, with a unique emphasis on the combinatorics of the transition matrices between bases of symmetric functions.  Chapter 3 uses this introductory material to describe how to find an assortment of generating functions for permutation statistics, and then these techniques are extended to find generating functions for a variety of objects in Chapter 4.  The next two chapters present the Robinson-Schensted-Knuth algorithm and a method for proving Pólya’s enu...

  1. Relativistic plasma dispersion functions

    International Nuclear Information System (INIS)

    Robinson, P.A.

    1986-01-01

    The known properties of plasma dispersion functions (PDF's) for waves in weakly relativistic, magnetized, thermal plasmas are reviewed and a large number of new results are presented. The PDF's required for the description of waves with small wave number perpendicular to the magnetic field (Dnestrovskii and Shkarofsky functions) are considered in detail; these functions also arise in certain quantum electrodynamical calculations involving strongly magnetized plasmas. Series, asymptotic series, recursion relations, integral forms, derivatives, differential equations, and approximations for these functions are discussed as are their analytic properties and connections with standard transcendental functions. In addition a more general class of PDF's relevant to waves of arbitrary perpendicular wave number is introduced and a range of properties of these functions are derived

  2. dftools: Distribution function fitting

    Science.gov (United States)

    Obreschkow, Danail

    2018-05-01

    dftools, written in R, finds the most likely P parameters of a D-dimensional distribution function (DF) generating N objects, where each object is specified by D observables with measurement uncertainties. For instance, if the objects are galaxies, it can fit a mass function (D=1), a mass-size distribution (D=2) or the mass-spin-morphology distribution (D=3). Unlike most common fitting approaches, this method accurately accounts for measurement in uncertainties and complex selection functions.

  3. Entropy and wigner functions

    Science.gov (United States)

    Manfredi; Feix

    2000-10-01

    The properties of an alternative definition of quantum entropy, based on Wigner functions, are discussed. Such a definition emerges naturally from the Wigner representation of quantum mechanics, and can easily quantify the amount of entanglement of a quantum state. It is shown that smoothing of the Wigner function induces an increase in entropy. This fact is used to derive some simple rules to construct positive-definite probability distributions which are also admissible Wigner functions.

  4. Entropy and Wigner Functions

    OpenAIRE

    Manfredi, G.; Feix, M. R.

    2002-01-01

    The properties of an alternative definition of quantum entropy, based on Wigner functions, are discussed. Such definition emerges naturally from the Wigner representation of quantum mechanics, and can easily quantify the amount of entanglement of a quantum state. It is shown that smoothing of the Wigner function induces an increase in entropy. This fact is used to derive some simple rules to construct positive definite probability distributions which are also admissible Wigner functions

  5. Time functions revisited

    Science.gov (United States)

    Fathi, Albert

    2015-07-01

    In this paper we revisit our joint work with Antonio Siconolfi on time functions. We will give a brief introduction to the subject. We will then show how to construct a Lipschitz time function in a simplified setting. We will end with a new result showing that the Aubry set is not an artifact of our proof of existence of time functions for stably causal manifolds.

  6. SPLINE, Spline Interpolation Function

    International Nuclear Information System (INIS)

    Allouard, Y.

    1977-01-01

    1 - Nature of physical problem solved: The problem is to obtain an interpolated function, as smooth as possible, that passes through given points. The derivatives of these functions are continuous up to the (2Q-1) order. The program consists of the following two subprograms: ASPLERQ. Transport of relations method for the spline functions of interpolation. SPLQ. Spline interpolation. 2 - Method of solution: The methods are described in the reference under item 10

  7. Hadron structure functions

    International Nuclear Information System (INIS)

    Martin, F.

    1981-03-01

    The x dependence of hadron structure functions is investigated. If quarks can exist in very low mass states (10 MeV for d and u quarks) the pion structure function is predicted to behave like (1-x) and not (1-x) 2 in a x-region around 1. Relativistic and non-relativistic quark bound state pictures of hadrons are considered together with their relation with the Q 2 evolution of structure functions. Good agreement with data is in general obtained

  8. Calculus of bivariant function

    OpenAIRE

    PTÁČNÍK, Jan

    2011-01-01

    This thesis deals with the introduction of function of two variables and differential calculus of this function. This work should serve as a textbook for students of elementary school's teacher. Each chapter contains a summary of basic concepts and explanations of relationships, then solved model exercises of the topic and finally the exercises, which should solve the student himself. Thesis have transmit to students basic knowledges of differential calculus of functions of two variables, inc...

  9. Functional esophageal disorders

    OpenAIRE

    Clouse, R; Richter, J; Heading, R; Janssens, J; Wilson, J

    1999-01-01

    The functional esophageal disorders include globus, rumination syndrome, and symptoms that typify esophageal diseases (chest pain, heartburn, and dysphagia). Factors responsible for symptom production are poorly understood. The criteria for diagnosis rest not only on compatible symptoms but also on exclusion of structural and metabolic disorders that might mimic the functional disorders. Additionally, a functional diagnosis is precluded by the presence of a pathology-based motor disorder or p...

  10. Functional Programming With Relations

    OpenAIRE

    Hutton, Graham

    1991-01-01

    While programming in a relational framework has much to offer over the functional style in terms of expressiveness, computing with relations is less efficient, and more semantically troublesome. In this paper we propose a novel blend of the functional and relational styles. We identify a class of "causal relations", which inherit some of the bi-directionality properties of relations, but retain the efficiency and semantic foundations of the functional style.

  11. Photon structure function

    International Nuclear Information System (INIS)

    Bardeen, W.A.

    1980-11-01

    Theoretical understanding of the photon structure function is reviewed. As an illustration of the pointlike component, the parton model is briefly discussed. However, the systematic study of the photon structure function is presented through the framework of the operator product expansion. Perturbative QCD is used as the theoretical basis for the calculation of leading contributions to the operator product expansion. The influence of higher order QCD effects on these results is discussed. Recent results for the polarized structure functions are discussed

  12. Nonrespiratory lung function

    International Nuclear Information System (INIS)

    Isawa, Toyoharu

    1994-01-01

    The function of the lungs is primarily the function as a gas exchanger: the venous blood returning to the lungs is arterialized with oxygen in the lungs and the arterialized blood is sent back again to the peripheral tissues of the whole body to be utilized for metabolic oxygenation. Besides the gas exchanging function which we call ''respiratory lung function'' the lungs have functions that have little to do with gas exchange itself. We categorically call the latter function of the lungs as ''nonrespiratory lung function''. The lungs consist of the conductive airways, the gas exchanging units like the alveoli, and the interstitial space that surrounds the former two compartments. The interstitial space contains the blood and lymphatic capillaries, collagen and elastic fibers and cement substances. The conductive airways and the gas exchanging units are directly exposed to the atmosphere that contains various toxic and nontoxic gases, fume and biological or nonbiological particles. Because the conductive airways are equipped with defense mechanisms like mucociliary clearance or coughs to get rid of these toxic gases, particles or locally produced biological debris, we are usually free from being succumbed to ill effects of inhaled materials. By use of nuclear medicine techniques, we can now evaluate mucociliary clearance function, and other nonrespiratory lung functions as well in vivo

  13. Subordination by convex functions

    Directory of Open Access Journals (Sweden)

    Rosihan M. Ali

    2006-01-01

    Full Text Available For a fixed analytic function g(z=z+∑n=2∞gnzn defined on the open unit disk and γ<1, let Tg(γ denote the class of all analytic functions f(z=z+∑n=2∞anzn satisfying ∑n=2∞|angn|≤1−γ. For functions in Tg(γ, a subordination result is derived involving the convolution with a normalized convex function. Our result includes as special cases several earlier works.

  14. Renormalization Group Functional Equations

    CERN Document Server

    Curtright, Thomas L

    2011-01-01

    Functional conjugation methods are used to analyze the global structure of various renormalization group trajectories. With minimal assumptions, the methods produce continuous flows from step-scaling {\\sigma} functions, and lead to exact functional relations for the local flow {\\beta} functions, whose solutions may have novel, exotic features, including multiple branches. As a result, fixed points of {\\sigma} are sometimes not true fixed points under continuous changes in scale, and zeroes of {\\beta} do not necessarily signal fixed points of the flow, but instead may only indicate turning points of the trajectories.

  15. Perceptual Audio Hashing Functions

    Directory of Open Access Journals (Sweden)

    Emin Anarım

    2005-07-01

    Full Text Available Perceptual hash functions provide a tool for fast and reliable identification of content. We present new audio hash functions based on summarization of the time-frequency spectral characteristics of an audio document. The proposed hash functions are based on the periodicity series of the fundamental frequency and on singular-value description of the cepstral frequencies. They are found, on one hand, to perform very satisfactorily in identification and verification tests, and on the other hand, to be very resilient to a large variety of attacks. Moreover, we address the issue of security of hashes and propose a keying technique, and thereby a key-dependent hash function.

  16. Nonrespiratory lung function

    Energy Technology Data Exchange (ETDEWEB)

    Isawa, Toyoharu [Tohoku University Research Institute for Chest Disease and Cancer, Sendai (Japan)

    1994-07-01

    The function of the lungs is primarily the function as a gas exchanger: the venous blood returning to the lungs is arterialized with oxygen in the lungs and the arterialized blood is sent back again to the peripheral tissues of the whole body to be utilized for metabolic oxygenation. Besides the gas exchanging function which we call ''respiratory lung function'' the lungs have functions that have little to do with gas exchange itself. We categorically call the latter function of the lungs as ''nonrespiratory lung function''. The lungs consist of the conductive airways, the gas exchanging units like the alveoli, and the interstitial space that surrounds the former two compartments. The interstitial space contains the blood and lymphatic capillaries, collagen and elastic fibers and cement substances. The conductive airways and the gas exchanging units are directly exposed to the atmosphere that contains various toxic and nontoxic gases, fume and biological or nonbiological particles. Because the conductive airways are equipped with defense mechanisms like mucociliary clearance or coughs to get rid of these toxic gases, particles or locally produced biological debris, we are usually free from being succumbed to ill effects of inhaled materials. By use of nuclear medicine techniques, we can now evaluate mucociliary clearance function, and other nonrespiratory lung functions as well in vivo.

  17. Control functions in MFM

    DEFF Research Database (Denmark)

    Lind, Morten

    2011-01-01

    Multilevel Flow Modeling (MFM) has been proposed as a tool for representing goals and functions of complex industrial plants and suggested as a basis for reasoning about control situations. Lind presents an introduction to MFM but do not describe how control functions are used in the modeling....... The purpose of the present paper is to serve as a companion paper to this introduction by explaining the basic principles used in MFM for representation of control functions. A theoretical foundation for modeling control functions is presented and modeling examples are given for illustration....

  18. Regulated functions and integrability

    Directory of Open Access Journals (Sweden)

    Ján Gunčaga

    2009-04-01

    Full Text Available Properties of functions defined on a bounded closed interval, weaker than continuity, have been considered by many mathematicians. Functions having both sides limits at each point are called regulated and were considered by J. Dieudonné [2], D. Fraňková [3] and others (see for example S. Banach [1], S. Saks [8]. The main class of functions we deal with consists of piece-wise constant ones. These functions play a fundamental role in the integration theory which had been developed by Igor Kluvanek (see Š. Tkacik [9]. We present an outline of this theory.

  19. Introduction to functional methods

    International Nuclear Information System (INIS)

    Faddeev, L.D.

    1976-01-01

    The functional integral is considered in relation to Feynman diagrams and phase space. The holomorphic form of the functional integral is then discussed. The main problem of the lectures, viz. the construction of the S-matrix by means of the functional integral, is considered. The functional methods described explicitly take into account the Bose statistics of the fields involved. The different procedure used to treat fermions is discussed. An introduction to the problem of quantization of gauge fields is given. (B.R.H.)

  20. The gamma function

    CERN Document Server

    Artin, Emil

    2015-01-01

    This brief monograph on the gamma function was designed by the author to fill what he perceived as a gap in the literature of mathematics, which often treated the gamma function in a manner he described as both sketchy and overly complicated. Author Emil Artin, one of the twentieth century's leading mathematicians, wrote in his Preface to this book, ""I feel that this monograph will help to show that the gamma function can be thought of as one of the elementary functions, and that all of its basic properties can be established using elementary methods of the calculus."" Generations of teachers

  1. Normal Functions As A New Way Of Defining Computable Functions

    Directory of Open Access Journals (Sweden)

    Leszek Dubiel

    2004-01-01

    Full Text Available Report sets new method of defining computable functions. This is formalization of traditional function descriptions, so it allows to define functions in very intuitive way. Discovery of Ackermann function proved that not all functions that can be easily computed can be so easily described with Hilbert’s system of recursive functions. Normal functions lack this disadvantage.

  2. Normal Functions as a New Way of Defining Computable Functions

    Directory of Open Access Journals (Sweden)

    Leszek Dubiel

    2004-01-01

    Full Text Available Report sets new method of defining computable functions. This is formalization of traditional function descriptions, so it allows to define functions in very intuitive way. Discovery of Ackermann function proved that not all functions that can be easily computed can be so easily described with Hilbert's system of recursive functions. Normal functions lack this disadvantage.

  3. Function spaces, 1

    CERN Document Server

    Pick, Luboš; John, Oldrich; Fucík, Svatopluk

    2012-01-01

    This is the first part of the second revised and extended edition of a well established monograph. It is an introduction to function spaces defined in terms of differentiability and integrability classes. It provides a catalogue of various spaces and benefits as a handbook for those who use function spaces to study other topics such as partial differential equations. Volum

  4. F-supercontinuous functions

    Directory of Open Access Journals (Sweden)

    J.K. Kohli

    2009-04-01

    Full Text Available A strong variant of continuity called ‘F-supercontinuity’ is introduced. The class of F-supercontinuous functions strictly contains the class of z-supercontinuous functions (Indian J. Pure Appl. Math. 33 (7 (2002, 1097–1108 which in turn properly contains the class of cl-supercontinuous functions ( clopen maps (Appl. Gen. Topology 8 (2 (2007, 293–300; Indian J. Pure Appl. Math. 14 (6 (1983, 762–772. Further, the class of F-supercontinuous functions is properly contained in the class of R-supercontinuous functions which in turn is strictly contained in the class of continuous functions. Basic properties of F-supercontinuous functions are studied and their place in the hierarchy of strong variants of continuity, which already exist in the mathematical literature, is elaborated. If either domain or range is a functionally regular space (Indagationes Math. 15 (1951, 359–368; 38 (1976, 281–288, then the notions of continuity, F-supercontinuity and R-supercontinuity coincide.

  5. Photon strength functions

    International Nuclear Information System (INIS)

    Bergqvist, I.

    1976-01-01

    Methods for extracting photon strength functions are briefly discussed. We follow the Brink-Axel approach to relate the strength functions to the giant resonances observed in photonuclear work and summarize the available data on the E1, E2 and M1 resonances. Some experimental and theoretical problems are outlined. (author)

  6. A Functional HAZOP Methodology

    DEFF Research Database (Denmark)

    Liin, Netta; Lind, Morten; Jensen, Niels

    2010-01-01

    A HAZOP methodology is presented where a functional plant model assists in a goal oriented decomposition of the plant purpose into the means of achieving the purpose. This approach leads to nodes with simple functions from which the selection of process and deviation variables follow directly...

  7. Functional Magnetic Resonance Imaging

    Science.gov (United States)

    Voos, Avery; Pelphrey, Kevin

    2013-01-01

    Functional magnetic resonance imaging (fMRI), with its excellent spatial resolution and ability to visualize networks of neuroanatomical structures involved in complex information processing, has become the dominant technique for the study of brain function and its development. The accessibility of in-vivo pediatric brain-imaging techniques…

  8. Cryptographic Hash Functions

    DEFF Research Database (Denmark)

    Gauravaram, Praveen; Knudsen, Lars Ramkilde

    2010-01-01

    functions, also called message authentication codes (MACs) serve data integrity and data origin authentication in the secret key setting. The building blocks of hash functions can be designed using block ciphers, modular arithmetic or from scratch. The design principles of the popular Merkle...

  9. Functional Assessment Inventory Manual.

    Science.gov (United States)

    Crewe, Nancy M.; Athelstan, Gary T.

    This manual, which provides extensive new instructions for administering the Functional Assessment Inventory (FAI), is intended to enable counselors to begin using the inventory without undergoing any special training. The first two sections deal with the need for functional assessment and issues in the development and use of the inventory. The…

  10. Functional and cognitive grammars

    Institute of Scientific and Technical Information of China (English)

    Anna Siewierska

    2011-01-01

    This paper presents a comprehensive review of the functional approach and cognitive approach to the nature of language and its relation to other aspects of human cognition. The paper starts with a brief discussion of the origins and the core tenets of the two approaches in Section 1. Section 2 discusses the similarities and differences between the three full-fledged structural functional grammars subsumed in the functional approach: Halliday's Systemic Functional Grammar (SFG), Dik's Functional Grammar (FG), and Van Valin's Role and Reference Grammar (RRG). Section 3 deals with the major features of the three cognitive frameworks: Langacker's Cognitive Grammar (CG), Goldberg's Cognitive Construction Grammar (CCG), and Croft's Radical Construction Grammar (RCG). Section 4 compares the two approaches and attempts to provide a unified functional-cognitive grammar. In the last section, the author concludes the paper with remarks on the unidirectional shift from functional grammar to cognitive grammar that may indicate a reinterpretation of the traditional relationship between functional and cognitive models of grammar.

  11. Heterogeneity in kinesin function

    NARCIS (Netherlands)

    Reddy, Babu J N; Tripathy, Suvranta; Vershinin, Michael; Tanenbaum, Marvin E; Xu, Jing; Mattson-Hoss, Michelle; Arabi, Karim; Chapman, Dail; Doolin, Tory; Hyeon, Changbong; Gross, Steven P

    2017-01-01

    The kinesin family proteins are often studied as prototypical molecular motors; a deeper understanding of them can illuminate regulation of intracellular transport. It is typically assumed that they function identically. Here we find that this assumption of homogeneous function appears incorrect:

  12. Thermal dielectric function

    International Nuclear Information System (INIS)

    Moneta, M.

    1999-01-01

    Thermal dielectric functions ε(k,ω) for homogeneous electron gas were determined and discussed. The ground state of the gas is described by the Fermi-Dirac momentum distribution. The low and high temperature limits of ε(k,ω) were related to the Lindhard dielectric function and to ε(k, omega) derived for Boltzmann and for classical momentum distributions, respectively. (author)

  13. Monadic Functional Reactive Programming

    NARCIS (Netherlands)

    A.J. van der Ploeg (Atze); C Shan

    2013-01-01

    htmlabstractFunctional Reactive Programming (FRP) is a way to program reactive systems in functional style, eliminating many of the problems that arise from imperative techniques. In this paper, we present an alternative FRP formulation that is based on the notion of a reactive computation: a

  14. The Grindahl Hash Functions

    DEFF Research Database (Denmark)

    Knudsen, Lars Ramkilde; Rechberger, Christian; Thomsen, Søren Steffen

    2007-01-01

    to the state. We propose two concrete hash functions, Grindahl-256 and Grindahl-512 with claimed security levels with respect to collision, preimage and second preimage attacks of 2^128 and 2^256, respectively. Both proposals have lower memory requirements than other hash functions at comparable speeds...

  15. Neurophysiology of functional imaging

    NARCIS (Netherlands)

    van Eijsden, Pieter; Hyder, Fahmeed; Rothman, Douglas L.; Shulman, Robert G.

    2009-01-01

    The successes of PET and fMRI in non-invasively localizing sensory functions had encouraged efforts to transform the subjective concepts of cognitive psychology into objective physical measures. The assumption was that mental functions could be decomposed into non-overlapping, context-independent

  16. properties and luminosity functions

    Directory of Open Access Journals (Sweden)

    Hektor Monteiro

    2007-01-01

    Full Text Available In this article, we present an investigation of a sample of 1072 stars extracted from the Villanova Catalog of Spectroscopically Identified White Dwarfs (2005 on-line version, studying their distribution in the Galaxy, their physical properties and their luminosity functions. The distances and physical properties of the white dwarfs are determined through interpolation of their (B-V or (b-y colors in model grids. The solar position relative to the Galactic plane, luminosity function, as well as separate functions for each white dwarf spectral type are derived and discussed. We show that the binary fraction does not vary significantly as a function of distance from the Galactic disk out to 100 pc. We propose that the formation rates of DA and non-DAs have changed over time and/or that DAs evolve into non-DA types. The luminosity functions for DAs and DBs have peaks possibly related to a star burst event.

  17. The triad value function

    DEFF Research Database (Denmark)

    Vedel, Mette

    2016-01-01

    the triad value function. Next, the applicability and validity of the concept is examined in a case study of four closed vertical supply chain triads. Findings - The case study demonstrates that the triad value function facilitates the analysis and understanding of an apparent paradox; that distributors...... are not dis-intermediated in spite of their limited contribution to activities in the triads. The results indicate practical adequacy of the triad value function. Research limitations/implications - The triad value function is difficult to apply in the study of expanded networks as the number of connections...... expands exponentially with the number of ties in the network. Moreover, it must be applied in the study of service triads and open vertical supply chain triads to further verify the practical adequacy of the concept. Practical implications - The triad value function cannot be used normatively...

  18. Pair Correlation Function Integrals

    DEFF Research Database (Denmark)

    Wedberg, Nils Hejle Rasmus Ingemar; O'Connell, John P.; Peters, Günther H.J.

    2011-01-01

    We describe a method for extending radial distribution functions obtained from molecular simulations of pure and mixed molecular fluids to arbitrary distances. The method allows total correlation function integrals to be reliably calculated from simulations of relatively small systems. The long......-distance behavior of radial distribution functions is determined by requiring that the corresponding direct correlation functions follow certain approximations at long distances. We have briefly described the method and tested its performance in previous communications [R. Wedberg, J. P. O’Connell, G. H. Peters......, and J. Abildskov, Mol. Simul. 36, 1243 (2010); Fluid Phase Equilib. 302, 32 (2011)], but describe here its theoretical basis more thoroughly and derive long-distance approximations for the direct correlation functions. We describe the numerical implementation of the method in detail, and report...

  19. Managing Functional Power

    DEFF Research Database (Denmark)

    Rosenstand, Claus Andreas Foss; Laursen, Per Kyed

    2013-01-01

    How does one manage functional power relations between leading functions in vision driven digital media creation, and this from idea to master during the creation cycle? Functional power is informal, and it is understood as roles, e.g. project manager, that provide opportunities to contribute...... to the product quality. The area of interest is the vision driven digital media industry in general; however, the point of departure is the game industry due to its aesthetic complexity. The article's contribution to the area is a power graph, which shows the functional power of the leading functions according...... to a general digital media creation cycle. This is used to point out potential power conflicts and their consequences. It is concluded that there is normally more conflict potential in vision driven digital media creation than in digital media creation in general or in software development. The method...

  20. Functional data analysis

    CERN Document Server

    Ramsay, J O

    1997-01-01

    Scientists today collect samples of curves and other functional observations. This monograph presents many ideas and techniques for such data. Included are expressions in the functional domain of such classics as linear regression, principal components analysis, linear modelling, and canonical correlation analysis, as well as specifically functional techniques such as curve registration and principal differential analysis. Data arising in real applications are used throughout for both motivation and illustration, showing how functional approaches allow us to see new things, especially by exploiting the smoothness of the processes generating the data. The data sets exemplify the wide scope of functional data analysis; they are drwan from growth analysis, meterology, biomechanics, equine science, economics, and medicine. The book presents novel statistical technology while keeping the mathematical level widely accessible. It is designed to appeal to students, to applied data analysts, and to experienced researc...

  1. The function of introns

    Directory of Open Access Journals (Sweden)

    Liran eCarmel

    2012-04-01

    Full Text Available The intron-exon architecture of many eukaryotic genes raises the intriguing question of whether this unique organization serves any function, or is it simply a result of the spread of functionless introns in eukaryotic genomes. In this review, we show that introns in contemporary species fulfill a broad spectrum of functions, and are involved in virtually every step of mRNA processing. We propose that this great diversity of intronic functions supports the notion that introns were indeed selfish elements in early eukaryotes, but then independently gained numerous functions in different eukaryotic lineages. We suggest a novel criterion of evolutionary conservation, dubbed intron positional conservation, which can identify functional introns.

  2. A phased translation function

    International Nuclear Information System (INIS)

    Read, R.J.; Schierbeek, A.J.

    1988-01-01

    A phased translation function, which takes advantage of prior phase information to determine the position of an oriented mulecular replacement model, is examined. The function is the coefficient of correlation between the electron density computed with the prior phases and the electron density of the translated model, evaluated in reciprocal space as a Fourier transform. The correlation coefficient used in this work is closely related to an overlap function devised by Colman, Fehlhammer and Bartels. Tests with two protein structures, one of which was solved with the help of the phased translation function, show that little phase information is required to resolve the translation problem, and that the function is relatively insensitive to misorientation of the model. (orig.)

  3. Submodular functions and optimization

    CERN Document Server

    Fujishige, Satoru

    2005-01-01

    It has widely been recognized that submodular functions play essential roles in efficiently solvable combinatorial optimization problems. Since the publication of the 1st edition of this book fifteen years ago, submodular functions have been showing further increasing importance in optimization, combinatorics, discrete mathematics, algorithmic computer science, and algorithmic economics, and there have been made remarkable developments of theory and algorithms in submodular functions. The 2nd edition of the book supplements the 1st edition with a lot of remarks and with new two chapters: "Submodular Function Minimization" and "Discrete Convex Analysis." The present 2nd edition is still a unique book on submodular functions, which is essential to students and researchers interested in combinatorial optimization, discrete mathematics, and discrete algorithms in the fields of mathematics, operations research, computer science, and economics. Key features: - Self-contained exposition of the theory of submodular ...

  4. Time Functions as Utilities

    Science.gov (United States)

    Minguzzi, E.

    2010-09-01

    Every time function on spacetime gives a (continuous) total preordering of the spacetime events which respects the notion of causal precedence. The problem of the existence of a (semi-)time function on spacetime and the problem of recovering the causal structure starting from the set of time functions are studied. It is pointed out that these problems have an analog in the field of microeconomics known as utility theory. In a chronological spacetime the semi-time functions correspond to the utilities for the chronological relation, while in a K-causal (stably causal) spacetime the time functions correspond to the utilities for the K + relation (Seifert’s relation). By exploiting this analogy, we are able to import some mathematical results, most notably Peleg’s and Levin’s theorems, to the spacetime framework. As a consequence, we prove that a K-causal (i.e. stably causal) spacetime admits a time function and that the time or temporal functions can be used to recover the K + (or Seifert) relation which indeed turns out to be the intersection of the time or temporal orderings. This result tells us in which circumstances it is possible to recover the chronological or causal relation starting from the set of time or temporal functions allowed by the spacetime. Moreover, it is proved that a chronological spacetime in which the closure of the causal relation is transitive (for instance a reflective spacetime) admits a semi-time function. Along the way a new proof avoiding smoothing techniques is given that the existence of a time function implies stable causality, and a new short proof of the equivalence between K-causality and stable causality is given which takes advantage of Levin’s theorem and smoothing techniques.

  5. Knowledge Enrichment Analysis for Human Tissue- Specific Genes Uncover New Biological Insights

    Directory of Open Access Journals (Sweden)

    Gong Xiu-Jun

    2012-06-01

    Full Text Available The expression and regulation of genes in different tissues are fundamental questions to be answered in biology. Knowledge enrichment analysis for tissue specific (TS and housekeeping (HK genes may help identify their roles in biological process or diseases and gain new biological insights.In this paper, we performed the knowledge enrichment analysis for 17,343 genes in 84 human tissues using Gene Set Enrichment Analysis (GSEA and Hypergeometric Analysis (HA against three biological ontologies: Gene Ontology (GO, KEGG pathways and Disease Ontology (DO respectively.The analyses results demonstrated that the functions of most gene groups are consistent with their tissue origins. Meanwhile three interesting new associations for HK genes and the skeletal muscle tissuegenes are found. Firstly, Hypergeometric analysis against KEGG database for HK genes disclosed that three disease terms (Parkinson’s disease, Huntington’s disease, Alzheimer’s disease are intensively enriched.Secondly, Hypergeometric analysis against the KEGG database for Skeletal Muscle tissue genes shows that two cardiac diseases of “Hypertrophic cardiomyopathy (HCM” and “Arrhythmogenic right ventricular cardiomyopathy (ARVC” are heavily enriched, which are also considered as no relationship with skeletal functions.Thirdly, “Prostate cancer” is intensively enriched in Hypergeometric analysis against the disease ontology (DO for the Skeletal Muscle tissue genes, which is a much unexpected phenomenon.

  6. Multidisciplinary team functioning.

    Science.gov (United States)

    Kovitz, K E; Dougan, P; Riese, R; Brummitt, J R

    1984-01-01

    This paper advocates the need to move beyond interdisciplinary team composition as a minimum criterion for multidisciplinary functioning in child abuse treatment. Recent developments within the field reflect the practice of shared professional responsibility for detection, case management and treatment. Adherence to this particular model for intervention requires cooperative service planning and implementation as task related functions. Implicitly, this model also carries the potential to incorporate the supportive functioning essential to effective group process. However, explicit attention to the dynamics and process of small groups has been neglected in prescriptive accounts of multidisciplinary child abuse team organization. The present paper therefore focuses upon the maintenance and enhancement aspects of multidisciplinary group functioning. First, the development and philosophy of service for the Alberta Children's Hospital Child Abuse Program are reviewed. Second, composition of the team, it's mandate for service, and the population it serves are briefly described. Third, the conceptual framework within which the program functions is outlined. Strategies for effective group functioning are presented and the difficulties encountered with this model are highlighted. Finally, recommendations are offered for planning and implementing a multidisciplinary child abuse team and for maintaining its effective group functioning.

  7. The Enzyme Function Initiative†

    Science.gov (United States)

    Gerlt, John A.; Allen, Karen N.; Almo, Steven C.; Armstrong, Richard N.; Babbitt, Patricia C.; Cronan, John E.; Dunaway-Mariano, Debra; Imker, Heidi J.; Jacobson, Matthew P.; Minor, Wladek; Poulter, C. Dale; Raushel, Frank M.; Sali, Andrej; Shoichet, Brian K.; Sweedler, Jonathan V.

    2011-01-01

    The Enzyme Function Initiative (EFI) was recently established to address the challenge of assigning reliable functions to enzymes discovered in bacterial genome projects; in this Current Topic we review the structure and operations of the EFI. The EFI includes the Superfamily/Genome, Protein, Structure, Computation, and Data/Dissemination Cores that provide the infrastructure for reliably predicting the in vitro functions of unknown enzymes. The initial targets for functional assignment are selected from five functionally diverse superfamilies (amidohydrolase, enolase, glutathione transferase, haloalkanoic acid dehalogenase, and isoprenoid synthase), with five superfamily-specific Bridging Projects experimentally testing the predicted in vitro enzymatic activities. The EFI also includes the Microbiology Core that evaluates the in vivo context of in vitro enzymatic functions and confirms the functional predictions of the EFI. The deliverables of the EFI to the scientific community include: 1) development of a large-scale, multidisciplinary sequence/structure-based strategy for functional assignment of unknown enzymes discovered in genome projects (target selection, protein production, structure determination, computation, experimental enzymology, microbiology, and structure-based annotation); 2) dissemination of the strategy to the community via publications, collaborations, workshops, and symposia; 3) computational and bioinformatic tools for using the strategy; 4) provision of experimental protocols and/or reagents for enzyme production and characterization; and 5) dissemination of data via the EFI’s website, enzymefunction.org. The realization of multidisciplinary strategies for functional assignment will begin to define the full metabolic diversity that exists in nature and will impact basic biochemical and evolutionary understanding, as well as a wide range of applications of central importance to industrial, medicinal and pharmaceutical efforts. PMID

  8. The Enzyme Function Initiative.

    Science.gov (United States)

    Gerlt, John A; Allen, Karen N; Almo, Steven C; Armstrong, Richard N; Babbitt, Patricia C; Cronan, John E; Dunaway-Mariano, Debra; Imker, Heidi J; Jacobson, Matthew P; Minor, Wladek; Poulter, C Dale; Raushel, Frank M; Sali, Andrej; Shoichet, Brian K; Sweedler, Jonathan V

    2011-11-22

    The Enzyme Function Initiative (EFI) was recently established to address the challenge of assigning reliable functions to enzymes discovered in bacterial genome projects; in this Current Topic, we review the structure and operations of the EFI. The EFI includes the Superfamily/Genome, Protein, Structure, Computation, and Data/Dissemination Cores that provide the infrastructure for reliably predicting the in vitro functions of unknown enzymes. The initial targets for functional assignment are selected from five functionally diverse superfamilies (amidohydrolase, enolase, glutathione transferase, haloalkanoic acid dehalogenase, and isoprenoid synthase), with five superfamily specific Bridging Projects experimentally testing the predicted in vitro enzymatic activities. The EFI also includes the Microbiology Core that evaluates the in vivo context of in vitro enzymatic functions and confirms the functional predictions of the EFI. The deliverables of the EFI to the scientific community include (1) development of a large-scale, multidisciplinary sequence/structure-based strategy for functional assignment of unknown enzymes discovered in genome projects (target selection, protein production, structure determination, computation, experimental enzymology, microbiology, and structure-based annotation), (2) dissemination of the strategy to the community via publications, collaborations, workshops, and symposia, (3) computational and bioinformatic tools for using the strategy, (4) provision of experimental protocols and/or reagents for enzyme production and characterization, and (5) dissemination of data via the EFI's Website, http://enzymefunction.org. The realization of multidisciplinary strategies for functional assignment will begin to define the full metabolic diversity that exists in nature and will impact basic biochemical and evolutionary understanding, as well as a wide range of applications of central importance to industrial, medicinal, and pharmaceutical efforts.

  9. Polysheroidal periodic functions

    International Nuclear Information System (INIS)

    Truskova, N.F.

    1985-01-01

    Separation of variables in the Helmholtz N-dimensional (N≥4) equation in polyspheroidal coordinate systems leads to the necessity of solving equations going over into equations for polyspheroidal periodic functions used for solving the two-centre problem in quantum mechanics, the three-body problem with Coulomb interaction, etc. For these functions the expansions are derived in terms of the Jacobi polynomials and Bessel functions. Their basic properties, asymptotics are considered. The algorithm of their computer calculations is developed. The results of numerical calculations are given

  10. cl-Supercontinuous Functions

    Directory of Open Access Journals (Sweden)

    D. Singh

    2007-10-01

    Full Text Available Basic properties of cl-supercontinuity, a strong variant of continuity, due to Reilly and Vamanamurthy [Indian J. Pure Appl. Math., 14 (1983, 767–772], who call such maps clopen continuous, are studied. Sufficient conditions on domain or range for a continuous function to be cl-supercontinuous are observed. Direct and inverse transfer of certain topological properties under cl-supercontinuous functions are studied and existence or nonexistence of certain cl-supercontinuous function with specified domain or range is outlined.

  11. Mean-periodic functions

    Directory of Open Access Journals (Sweden)

    Carlos A. Berenstein

    1980-01-01

    Full Text Available We show that any mean-periodic function f can be represented in terms of exponential-polynomial solutions of the same convolution equation f satisfies, i.e., u∗f=0(μ∈E′(ℝn. This extends to n-variables the work of L. Schwartz on mean-periodicity and also extends L. Ehrenpreis' work on partial differential equations with constant coefficients to arbitrary convolutors. We also answer a number of open questions about mean-periodic functions of one variable. The basic ingredient is our work on interpolation by entire functions in one and several complex variables.

  12. Functional Amyloids in Reproduction.

    Science.gov (United States)

    Hewetson, Aveline; Do, Hoa Quynh; Myers, Caitlyn; Muthusubramanian, Archana; Sutton, Roger Bryan; Wylie, Benjamin J; Cornwall, Gail A

    2017-06-29

    Amyloids are traditionally considered pathological protein aggregates that play causative roles in neurodegenerative disease, diabetes and prionopathies. However, increasing evidence indicates that in many biological systems nonpathological amyloids are formed for functional purposes. In this review, we will specifically describe amyloids that carry out biological roles in sexual reproduction including the processes of gametogenesis, germline specification, sperm maturation and fertilization. Several of these functional amyloids are evolutionarily conserved across several taxa, including human, emphasizing the critical role amyloids perform in reproduction. Evidence will also be presented suggesting that, if altered, some functional amyloids may become pathological.

  13. THE PSEUDO-SMARANDACHE FUNCTION

    OpenAIRE

    David Gorski

    2007-01-01

    The Pseudo-Smarandache Function is part of number theory. The function comes from the Smarandache Function. The Pseudo-Smarandache Function is represented by Z(n) where n represents any natural number.

  14. Coded Network Function Virtualization

    DEFF Research Database (Denmark)

    Al-Shuwaili, A.; Simone, O.; Kliewer, J.

    2016-01-01

    Network function virtualization (NFV) prescribes the instantiation of network functions on general-purpose network devices, such as servers and switches. While yielding a more flexible and cost-effective network architecture, NFV is potentially limited by the fact that commercial off......-the-shelf hardware is less reliable than the dedicated network elements used in conventional cellular deployments. The typical solution for this problem is to duplicate network functions across geographically distributed hardware in order to ensure diversity. In contrast, this letter proposes to leverage channel...... coding in order to enhance the robustness on NFV to hardware failure. The proposed approach targets the network function of uplink channel decoding, and builds on the algebraic structure of the encoded data frames in order to perform in-network coding on the signals to be processed at different servers...

  15. Functional Use Database (FUse)

    Data.gov (United States)

    U.S. Environmental Protection Agency — There are five different files for this dataset: 1. A dataset listing the reported functional uses of chemicals (FUse) 2. All 729 ToxPrint descriptors obtained from...

  16. Contributing to Functionality

    DEFF Research Database (Denmark)

    Törpel, Bettina

    2006-01-01

    The objective of this paper is the design of computer supported joint action spaces. It is argued against a view of functionality as residing in computer applications. In such a view the creation of functionality is equivalent to the creation of computer applications. Functionality, in the view...... advocated in this paper, emerges in the specific dynamic interplay of actors, objectives, structures, practices and means. In this view, functionality is the result of creating, harnessing and inhabiting computer supported joint action spaces. The successful creation and further development of a computer...... supported joint action space comprises a whole range of appropriate design contributions. The approach is illustrated by the example of the creation of the computer supported joint action space "exchange network of voluntary union educators". As part of the effort a group of participants created...

  17. Liver Function Tests

    Science.gov (United States)

    ... Liver Function Tests Clinical Trials Liver Transplant FAQs Medical Terminology Diseases of the Liver Alagille Syndrome Alcohol-Related ... the Liver The Progression of Liver Disease FAQs Medical Terminology HOW YOU CAN HELP Sponsorship Ways to Give ...

  18. Introduction to structure functions

    International Nuclear Information System (INIS)

    Kwiecinski, J.

    1996-07-01

    The theory of deep inelastic scattering structure functions is reviewed with an emphasis put on the QCD expectations of their behaviour in the region of small values of Bjorken parameter x. (author). 56 refs

  19. Bioprinting: Functional droplet networks

    Science.gov (United States)

    Durmus, Naside Gozde; Tasoglu, Savas; Demirci, Utkan

    2013-06-01

    Tissue-mimicking printed networks of droplets separated by lipid bilayers that can be functionalized with membrane proteins are able to spontaneously fold and transmit electrical currents along predefined paths.

  20. Center for Functional Nanomaterials

    Data.gov (United States)

    Federal Laboratory Consortium — The Center for Functional Nanomaterials (CFN) explores the unique properties of materials and processes at the nanoscale. The CFN is a user-oriented research center...

  1. density functional theory approach

    Indian Academy of Sciences (India)

    YOGESH ERANDE

    2017-07-27

    Jul 27, 2017 ... a key role in all optical switching devices, since their optical properties can be .... optimized in the gas phase using Density Functional Theory. (DFT).39 The ...... The Mediation of Electrostatic Effects by Sol- vents J. Am. Chem.

  2. Reasoning about Function Objects

    Science.gov (United States)

    Nordio, Martin; Calcagno, Cristiano; Meyer, Bertrand; Müller, Peter; Tschannen, Julian

    Modern object-oriented languages support higher-order implementations through function objects such as delegates in C#, agents in Eiffel, or closures in Scala. Function objects bring a new level of abstraction to the object-oriented programming model, and require a comparable extension to specification and verification techniques. We introduce a verification methodology that extends function objects with auxiliary side-effect free (pure) methods to model logical artifacts: preconditions, postconditions and modifies clauses. These pure methods can be used to specify client code abstractly, that is, independently from specific instantiations of the function objects. To demonstrate the feasibility of our approach, we have implemented an automatic prover, which verifies several non-trivial examples.

  3. Normal Functioning Family

    Science.gov (United States)

    ... Spread the Word Shop AAP Find a Pediatrician Family Life Medical Home Family Dynamics Adoption & Foster Care ... Español Text Size Email Print Share Normal Functioning Family Page Content Article Body Is there any way ...

  4. Fundamentals of functional analysis

    CERN Document Server

    Farenick, Douglas

    2016-01-01

    This book provides a unique path for graduate or advanced undergraduate students to begin studying the rich subject of functional analysis with fewer prerequisites than is normally required. The text begins with a self-contained and highly efficient introduction to topology and measure theory, which focuses on the essential notions required for the study of functional analysis, and which are often buried within full-length overviews of the subjects. This is particularly useful for those in applied mathematics, engineering, or physics who need to have a firm grasp of functional analysis, but not necessarily some of the more abstruse aspects of topology and measure theory normally encountered. The reader is assumed to only have knowledge of basic real analysis, complex analysis, and algebra. The latter part of the text provides an outstanding treatment of Banach space theory and operator theory, covering topics not usually found together in other books on functional analysis. Written in a clear, concise manner,...

  5. Smooth functions statistics

    International Nuclear Information System (INIS)

    Arnold, V.I.

    2006-03-01

    To describe the topological structure of a real smooth function one associates to it the graph, formed by the topological variety, whose points are the connected components of the level hypersurface of the function. For a Morse function, such a graph is a tree. Generically, it has T triple vertices, T + 2 endpoints, 2T + 2 vertices and 2T + 1 arrows. The main goal of the present paper is to study the statistics of the graphs, corresponding to T triple points: what is the growth rate of the number φ(T) of different graphs? Which part of these graphs is representable by the polynomial functions of corresponding degree? A generic polynomial of degree n has at most (n - 1) 2 critical points on R 2 , corresponding to 2T + 2 = (n - 1) 2 + 1, that is to T = 2k(k - 1) saddle-points for degree n = 2k

  6. Structure function monitor

    Science.gov (United States)

    McGraw, John T [Placitas, NM; Zimmer, Peter C [Albuquerque, NM; Ackermann, Mark R [Albuquerque, NM

    2012-01-24

    Methods and apparatus for a structure function monitor provide for generation of parameters characterizing a refractive medium. In an embodiment, a structure function monitor acquires images of a pupil plane and an image plane and, from these images, retrieves the phase over an aperture, unwraps the retrieved phase, and analyzes the unwrapped retrieved phase. In an embodiment, analysis yields atmospheric parameters measured at spatial scales from zero to the diameter of a telescope used to collect light from a source.

  7. Sexual Function Across Aging.

    Science.gov (United States)

    Clayton, Anita H; Harsh, Veronica

    2016-03-01

    Women experience multiple changes in social and reproductive statuses across the life span which can affect sexual functioning. Various phases of the sexual response cycle may be impacted and can lead to sexual dysfunction. Screening for sexual problems and consideration of contributing factors such as neurobiology, reproductive life events, medical problems, medication use, and depression can help guide appropriate treatment and thereby improve the sexual functioning and quality of life of affected women. Treatment options include psychotropic medications, hormone therapy, and psychotherapy.

  8. Inequalities for Humbert functions

    Directory of Open Access Journals (Sweden)

    Ayman Shehata

    2014-04-01

    Full Text Available This paper is motivated by an open problem of Luke’s theorem. We consider the problem of developing a unified point of view on the theory of inequalities of Humbert functions and of their general ratios are obtained. Some particular cases and refinements are given. Finally, we obtain some important results involving inequalities of Bessel and Whittaker’s functions as applications.

  9. Functionally graded materials

    CERN Document Server

    Mahamood, Rasheedat Modupe

    2017-01-01

    This book presents the concept of functionally graded materials as well as their use and different fabrication processes. The authors describe the use of additive manufacturing technology for the production of very complex parts directly from the three dimension computer aided design of the part by adding material layer after layer. A case study is also presented in the book on the experimental analysis of functionally graded material using laser metal deposition process.

  10. [Functional (psychogenic) vertigo].

    Science.gov (United States)

    Diukova, G M; Zamergrad, M V; Golubev, V L; Adilova, S M; Makarov, S A

    Psychogenic (functional) vertigo is in second place by frequency after benign positional paroxysmal vertigo. It is often difficult to make the diagnosis, diagnostic program is expensive and traditional treatment often is not effective. This literature review covers current concepts on the terminology, clinical signs, pathogenesis and treatment approaches with regard to functional vertigo. Special attention is given to cerebral mechanisms of the pathogenesis including cognitive aspects.

  11. NEUROFEEDBACK USING FUNCTIONAL SPECTROSCOPY

    OpenAIRE

    Hinds, Oliver; Wighton, Paul; Tisdall, M. Dylan; Hess, Aaron; Breiter, Hans; van der Kouwe, André

    2014-01-01

    Neurofeedback based on real-time measurement of the blood oxygenation level-dependent (BOLD) signal has potential for treatment of neurological disorders and behavioral enhancement. Commonly employed methods are based on functional magnetic resonance imaging (fMRI) sequences that sacrifice speed and accuracy for whole-brain coverage, which is unnecessary in most applications. We present multi-voxel functional spectroscopy (MVFS): a system for computing the BOLD signal from multiple volumes of...

  12. Applied functional analysis

    CERN Document Server

    Griffel, DH

    2002-01-01

    A stimulating introductory text, this volume examines many important applications of functional analysis to mechanics, fluid mechanics, diffusive growth, and approximation. Detailed enough to impart a thorough understanding, the text is also sufficiently straightforward for those unfamiliar with abstract analysis. Its four-part treatment begins with distribution theory and discussions of Green's functions. Essentially independent of the preceding material, the second and third parts deal with Banach spaces, Hilbert space, spectral theory, and variational techniques. The final part outlines the

  13. Pancreatic Exocrine Function Testing

    OpenAIRE

    Berk, J. Edward

    1982-01-01

    It is important to understand which pancreatic function tests are available and how to interpret them when evaluating patients with malabsorption. Available direct tests are the secretin stimulation test, the Lundh test meal, and measurement of serum or fecal enzymes. Indirect tests assess pancreatic exocrine function by measuring the effect of pancreatic secretion on various nutrients. These include triglycerides labeled with carbon 14, cobalamin labeled with cobalt 57 and cobalt 58, and par...

  14. Purely Functional Structured Programming

    OpenAIRE

    Obua, Steven

    2010-01-01

    The idea of functional programming has played a big role in shaping today's landscape of mainstream programming languages. Another concept that dominates the current programming style is Dijkstra's structured programming. Both concepts have been successfully married, for example in the programming language Scala. This paper proposes how the same can be achieved for structured programming and PURELY functional programming via the notion of LINEAR SCOPE. One advantage of this proposal is that m...

  15. Exponential and Logarithmic Functions

    OpenAIRE

    Todorova, Tamara

    2010-01-01

    Exponential functions find applications in economics in relation to growth and economic dynamics. In these fields, quite often the choice variable is time and economists are trying to determine the best timing for certain economic activities to take place. An exponential function is one in which the independent variable appears in the exponent. Very often that exponent is time. In highly mathematical courses, it is a truism that students learn by doing, not by reading. Tamara Todorova’s Pr...

  16. Handbook of functional equations functional inequalities

    CERN Document Server

    2014-01-01

    As Richard Bellman has so elegantly stated at the Second International Conference on General Inequalities (Oberwolfach, 1978), “There are three reasons for the study of inequalities: practical, theoretical, and aesthetic.” On the aesthetic aspects, he said, “As has been pointed out, beauty is in the eye of the beholder. However, it is generally agreed that certain pieces of music, art, or mathematics are beautiful. There is an elegance to inequalities that makes them very attractive.” The content of the Handbook focuses mainly on both old and recent developments on approximate homomorphisms, on a relation between the Hardy–Hilbert and the Gabriel inequality, generalized Hardy–Hilbert type inequalities on multiple weighted Orlicz spaces, half-discrete Hilbert-type inequalities, on affine mappings, on contractive operators, on multiplicative Ostrowski and trapezoid inequalities, Ostrowski type inequalities for the  Riemann–Stieltjes integral, means and related functional inequalities, Weighted G...

  17. Comparison of two matrix-assisted laser desorption ionization-time of flight mass spectrometry systems for the identification of clinical filamentous fungi.

    Science.gov (United States)

    Huang, Yanfei; Zhang, Mingxin; Zhu, Min; Wang, Mei; Sun, Yufeng; Gu, Haitong; Cao, Jingjing; Li, Xue; Zhang, Shaoya; Wang, Jinglin; Lu, Xinxin

    2017-07-01

    Infections caused by filamentous fungi have become a health concern, and require rapid and accurate identification in order for effective treatment of the pathogens. To compare the performance of two MALDI-TOF MS systems (Bruker Microflex LT and Xiamen Microtyper) in the identification of filamentous fungal species. A total of 374 clinical filamentous fungal isolates sequentially collected in the Clinical Laboratory at the Beijing Tongren Hospital between January 2014 and December 2015 were identified by traditional phenotypic methods, Bruker Microflex LT and Xiamen Microtyper MALDI-TOF MS, respectively. The discrepancy between these methods was resolved by sequencing for definitive identification. Bruker Microflex LT and Xiamen Microtyper had similar correct species ID (98.9 vs. 99.2%), genus ID (99.7 vs. 100%), mis-ID (0.3 vs. 0%) and no ID (0 vs. 0). The rate of correct species identification by both MALDI-TOF MS (98.9 and 99.2%, respectively) was much higher compared with phenotypic approach (91.9%). Both MALDI-TOF MS systems provide accurate identification of clinical filamentous fungi compared with conventional phenotypic method, and have the potential to replace identification for routine identification of these fungi in clinical mycology laboratories. Both systems have similar performance in the identification of clinical filamentous fungi.

  18. Comparison of two matrix-assisted laser desorption ionisation-time of flight mass spectrometry methods for the identification of clinically relevant anaerobic bacteria

    NARCIS (Netherlands)

    Veloo, A. C. M.; Knoester, M.; Degener, J. E.; Kuijper, E. J.

    2011-01-01

    Two commercially available MALDI-TOF MS systems, Bruker MS and Shimadzu MS, were compared for the identification of clinically relevant anaerobic bacteria. A selection of 79 clinical isolates, representing 19 different genera, were tested and compared with identification obtained by 16S rRNA gene

  19. Functional Neuroimaging in Psychopathy.

    Science.gov (United States)

    Del Casale, Antonio; Kotzalidis, Georgios D; Rapinesi, Chiara; Di Pietro, Simone; Alessi, Maria Chiara; Di Cesare, Gianluigi; Criscuolo, Silvia; De Rossi, Pietro; Tatarelli, Roberto; Girardi, Paolo; Ferracuti, Stefano

    2015-01-01

    Psychopathy is associated with cognitive and affective deficits causing disruptive, harmful and selfish behaviour. These have considerable societal costs due to recurrent crime and property damage. A better understanding of the neurobiological bases of psychopathy could improve therapeutic interventions, reducing the related social costs. To analyse the major functional neural correlates of psychopathy, we reviewed functional neuroimaging studies conducted on persons with this condition. We searched the PubMed database for papers dealing with functional neuroimaging and psychopathy, with a specific focus on how neural functional changes may correlate with task performances and human behaviour. Psychopathy-related behavioural disorders consistently correlated with dysfunctions in brain areas of the orbitofrontal-limbic (emotional processing and somatic reaction to emotions; behavioural planning and responsibility taking), anterior cingulate-orbitofrontal (correct assignment of emotional valence to social stimuli; violent/aggressive behaviour and challenging attitude) and prefrontal-temporal-limbic (emotional stimuli processing/response) networks. Dysfunctional areas more consistently included the inferior frontal, orbitofrontal, dorsolateral prefrontal, ventromedial prefrontal, temporal (mainly the superior temporal sulcus) and cingulated cortices, the insula, amygdala, ventral striatum and other basal ganglia. Emotional processing and learning, and several social and affective decision-making functions are impaired in psychopathy, which correlates with specific changes in neural functions. © 2015 S. Karger AG, Basel.

  20. Functional integration over geometries

    International Nuclear Information System (INIS)

    Mottola, E.

    1995-01-01

    The geometric construction of the functional integral over coset spaces M/G is reviewed. The inner product on the cotangent space of infinitesimal deformations of M defines an invariant distance and volume form, or functional integration measure on the full configuration space. Then, by a simple change of coordinates parameterizing the gauge fiber G, the functional measure on the coset space M/G is deduced. This change of integration variables leads to a Jacobian which is entirely equivalent to the Faddeev--Popov determinant of the more traditional gauge fixed approach in non-abelian gauge theory. If the general construction is applied to the case where G is the group of coordinate reparameterizations of spacetime, the continuum functional integral over geometries, i.e. metrics modulo coordinate reparameterizations may be defined. The invariant functional integration measure is used to derive the trace anomaly and effective action for the conformal part of the metric in two and four dimensional spacetime. In two dimensions this approach generates the Polyakov--Liouville action of closed bosonic non-critical string theory. In four dimensions the corresponding effective action leads to novel conclusions on the importance of quantum effects in gravity in the far infrared, and in particular, a dramatic modification of the classical Einstein theory at cosmological distance scales, signaled first by the quantum instability of classical de Sitter spacetime. Finite volume scaling relations for the functional integral of quantum gravity in two and four dimensions are derived, and comparison with the discretized dynamical triangulation approach to the integration over geometries are discussed. Outstanding unsolved problems in both the continuum definition and the simplicial approach to the functional integral over geometries are highlighted

  1. Renal Function in Hypothyroidism

    International Nuclear Information System (INIS)

    Khalid, S.; Khalid, M; Elfaki, M.; Hassan, N.; Suliman, S.M.

    2007-01-01

    Background Hypothyroidism induces significant changes in the function of organ systems such as the heart, muscles and brain. Renal function is also influenced by thyroid status. Physiological effects include changes in water and electrolyte metabolism, notably hyponatremia, and reliable alterations of renal hemodynamics, including decrements in renal blood flow, renal plasma flow, glomerular filtration rate (GFR). Objective Renal function is profoundly influenced by thyroid status; the purpose of the present study was to determine the relationship between renal function and thyroid status of patients with hypothyroidism. Design and Patients In 5 patients with primary hypothyroidism and control group renal functions are measured by serum creatinine and glomerular filtration rate (GFR) using modified in diet renal disease (MDRD) formula. Result In hypothyroidism, mean serum creatinine increased and mean estimated GFR decreased, compared to the control group mean serum creatinine decreased and mean estimated GFR Increased. The hypothyroid patients showed elevated serum creatinine levels (> 1.1mg/dl) compared to control group (p value .000). In patients mean estimated GFR decreased, compared to mean estimated GFR increased in the control group (p value= .002).

  2. The Functions of Sleep

    Directory of Open Access Journals (Sweden)

    Samson Z Assefa

    2015-08-01

    Full Text Available Sleep is a ubiquitous component of animal life including birds and mammals. The exact function of sleep has been one of the mysteries of biology. A considerable number of theories have been put forward to explain the reason(s for the necessity of sleep. To date, while a great deal is known about what happens when animals sleep, there is no definitive comprehensive explanation as to the reason that sleep is an inevitable part of animal functioning. It is well known that sleep is a homeostatically regulated body process, and that prolonged sleep deprivation is fatal in animals. In this paper, we present some of the theories as to the functions of sleep and provide a review of some hypotheses as to the overall physiologic function of sleep. To better understand the purpose for sleeping, we review the effects of sleep deprivation on physical, neurocognitive and psychic function. A better understanding of the purpose for sleeping will be a great advance in our understanding of the nature of the animal kingdom, including our own.

  3. Renal Function in Hypothyroidism

    International Nuclear Information System (INIS)

    Khalid, A. S; Ahmed, M.I; Elfaki, H.M; Hassan, N.; Suliman, S. M.

    2006-12-01

    Background hypothyroidism induces significant changes in the function of organ systems such as the heart, muscles and brain. Renal function is also influenced by thyroid status. Physiological effects include changes in water and electrolyte metabolism, notably hyponatraemia, and reliable alterations of renal hemodynamics, including decrements in renal blood flow, renal plasma flow, glomerular filtration rate (GFR). Objective renal function is profoundly influenced by thyroid status, the purpose of the present study was to determine the relationship between renal function and thyroid status of patients with hypothyroidism. Design and patients in 5 patients with primary hypothyroidism and control group renal functions are measured by serum creatinine and glomerular filtration rate(GFR) using modified in diet renal disease (MDRD) formula. Result in hypothyroidism, mean serum creatinine increased and mean estimated GFR decreased, compared to the control group mean serum creatinine decreased and mean estimated GFR increased. The hypothyroid patients showed elevated serum creatinine levels(>1.1 mg/d1) compared to control group (p value= 000). In patients mean estimated GFR increased in the control group (p value=.002).Conclusion thus the kidney, in addition to the brain, heart and muscle, is an important target of the action of thyroid hormones.(Author)

  4. The tensor distribution function.

    Science.gov (United States)

    Leow, A D; Zhu, S; Zhan, L; McMahon, K; de Zubicaray, G I; Meredith, M; Wright, M J; Toga, A W; Thompson, P M

    2009-01-01

    Diffusion weighted magnetic resonance imaging is a powerful tool that can be employed to study white matter microstructure by examining the 3D displacement profile of water molecules in brain tissue. By applying diffusion-sensitized gradients along a minimum of six directions, second-order tensors (represented by three-by-three positive definite matrices) can be computed to model dominant diffusion processes. However, conventional DTI is not sufficient to resolve more complicated white matter configurations, e.g., crossing fiber tracts. Recently, a number of high-angular resolution schemes with more than six gradient directions have been employed to address this issue. In this article, we introduce the tensor distribution function (TDF), a probability function defined on the space of symmetric positive definite matrices. Using the calculus of variations, we solve the TDF that optimally describes the observed data. Here, fiber crossing is modeled as an ensemble of Gaussian diffusion processes with weights specified by the TDF. Once this optimal TDF is determined, the orientation distribution function (ODF) can easily be computed by analytic integration of the resulting displacement probability function. Moreover, a tensor orientation distribution function (TOD) may also be derived from the TDF, allowing for the estimation of principal fiber directions and their corresponding eigenvalues.

  5. Lunar neutron source function

    International Nuclear Information System (INIS)

    Kornblum, J.J.

    1974-01-01

    The search for a quantitative neutron source function for the lunar surface region is justified because it contributes to our understanding of the history of the lunar surface and of nuclear process occurring on the moon since its formation. A knowledge of the neutron source function and neutron flux distribution is important for the interpretation of many experimental measurements. This dissertation uses the available pertinent experimental measurements together with theoretical calculations to obtain an estimate of the lunar neutron source function below 15 MeV. Based upon reasonable assumptions a lunar neutron source function having adjustable parameters is assumed for neutrons below 15 MeV. The lunar neutron source function is composed of several components resulting from the action of cosmic rays with lunar material. A comparison with previous neutron calculations is made and significant differences are discussed. Application of the results to the problem of lunar soil histories is examined using the statistical model for soil development proposed by Fireman. The conclusion is drawn that the moon is losing mass

  6. Functional (psychogenic) stereotypies.

    Science.gov (United States)

    Baizabal-Carvallo, José Fidel; Jankovic, Joseph

    2017-07-01

    Functional (psychogenic) movement disorders (FMDs) may present with a broad spectrum of phenomenology including stereotypic movements. We aimed to characterize the phenomenology of functional stereotypies and compare these features with those observed in 65 patients with tardive dyskinesia (TD). From a cohort of 184 patients with FMDs, we identified 19 (10.3%) with functional stereotypies (FS). There were 15 women and 4 men, with a mean age at onset of 38.6 ± 17.4 years. Among the patients with FS, there were 9 (47%) with orolingual dyskinesia/stereotypy, 9 (47%) with limb stereotypies, 6 (32%) with trunk stereotypies, and 2 (11%) with respiratory dyskinesia as part of orofacial-laryngeal-trunk stereotypy. These patients showed signs commonly seen in FMDs such as sudden onset (84%), prominent distractibility (58%), and periods of unexplained improvement (84%) that were not reported in patients with TD. Besides a much lower frequency of exposure to potential offending drugs, patients with FS differed from those with classic TD by a younger age at onset, lack of self-biting, uncommon chewing movements, more frequent lingual movements without mouth dyskinesia, and associated functional tremor and abnormal speech. Lack of self-biting showed the highest sensitivity (1.0) and abnormal speech showed the highest specificity (0.9) for the diagnosis of functional orolingual dyskinesia. FS represent part of the clinical spectrum of FMDs. Clinical and demographic features are helpful in distinguishing patients with FS from those with TD.

  7. Functional Anorectal Disorders.

    Science.gov (United States)

    Rao, Satish Sc; Bharucha, Adil E; Chiarioni, Giuseppe; Felt-Bersma, Richelle; Knowles, Charles; Malcolm, Allison; Wald, Arnold

    2016-03-25

    This report defines criteria and reviews the epidemiology, pathophysiology, and management of common anorectal disorders: fecal incontinence (FI), functional anorectal pain and functional defecation disorders. FI is defined as the recurrent uncontrolled passage of fecal material for at least 3 months. The clinical features of FI are useful for guiding diagnostic testing and therapy. Anorectal manometry and imaging are useful for evaluating anal and pelvic floor structure and function. Education, antidiarrheals and biofeedback therapy are the mainstay of management; surgery may be useful in refractory cases. Functional anorectal pain syndromes are defined by clinical features and categorized into three subtypes. In proctalgia fugax, the pain is typically fleeting and lasts for seconds to minutes. In levator ani syndrome (LAS) and unspecified anorectal pain the pain lasts more than 30 minutes, but in LAS there is puborectalis tenderness. Functional defecation disorders are defined by >2 symptoms of chronic constipation or irritable bowel syndrome with constipation, and with >2 features of impaired evacuation i.e., abnormal evacuation pattern on manometry, abnormal balloon expulsion test or impaired rectal evacuation by imaging. It includes two subtypes; dyssynergic defecation and inadequate defecatory propulsion. Pelvic floor biofeedback therapy is effective for treating LAS and defecatory disorders. Copyright © 2016 AGA Institute. Published by Elsevier Inc. All rights reserved.

  8. Educating Executive Function

    Science.gov (United States)

    Blair, Clancy

    2016-01-01

    Executive functions are thinking skills that assist with reasoning, planning, problem solving, and managing one’s life. The brain areas that underlie these skills are interconnected with and influenced by activity in many different brain areas, some of which are associated with emotion and stress. One consequence of the stress-specific connections is that executive functions, which help us to organize our thinking, tend to be disrupted when stimulation is too high and we are stressed out, or too low when we are bored and lethargic. Given their central role in reasoning and also in managing stress and emotion, scientists have conducted studies, primarily with adults, to determine whether executive functions can be improved by training. By and large, results have shown that they can be, in part through computer-based videogame-like activities. Evidence of wider, more general benefits from such computer-based training, however, is mixed. Accordingly, scientists have reasoned that training will have wider benefits if it is implemented early, with very young children as the neural circuitry of executive functions is developing, and that it will be most effective if embedded in children’s everyday activities. Evidence produced by this research, however, is also mixed. In sum, much remains to be learned about executive function training. Without question, however, continued research on this important topic will yield valuable information about cognitive development. PMID:27906522

  9. The function of dreaming.

    Science.gov (United States)

    Staunton, H

    2001-01-01

    Theories on the function of REM sleep and dreaming, with which it has a contingent relationship, remain diverse. They include facilitation of memory storage, reverse learning, anatomical and functional brain maturation, catecholamine restoration, psychoanalytical (wish fulfilment or otherwise). It is possible that one function is grafted onto another as the personality develops. Given a close relationship between REM sleep and dreaming, and given that the neonate spends 18 hours asleep per day, of which 12 hours are spent in REM sleep, it is logical to look in the neonate for a primary function of dreaming. The two constants in the dreaming process are: 1) the dreamer is always present as first person observer; 2) there is always a topographical setting. Based on the foregoing, it is proposed that a major function of REM sleep is the development and maintenance of a sense of personal identity, through creating a 'being there' environment at regular intervals during prolonged periods of absence from a waking state in topographical surrounds. The infant cannot forget who he/she is. Thus, he/she develops a clear sense of his/her own identity, or the 'I'ness of me', and a sense of his/her separateness from the topographical world. At the same time, by largely forgetting the dreams, he/she is not burdened by the need for an elaborate method of storage of the vicarious and bizarre experiences.

  10. Effect of functional overreaching on executive functions.

    Science.gov (United States)

    Dupuy, O; Renaud, M; Bherer, L; Bosquet, L

    2010-09-01

    The aim of this study was to investigate whether cognitive performance was a valid marker of overreaching. 10 well-trained male endurance athletes increased their training load by 100% for 2 weeks. They performed a maximal graded test, a constant speed test, a reaction time task and a computerized version of the Stroop color word-test before and after this overload period. Regarding performance results, five participants were considered as overreached and the five remaining were considered as well-trained. We found no significant differences between groups in performing the Stroop test. Noteworthy, we found a small increase in response time in the more complex condition in overreached athletes (1 188+/-261 to 1 297+/-231 ms, effect size=0.44), while it decreased moderately in the well-trained athletes (1 066+/-175 to 963+/-171 ms, effect size=-0.59). Furthermore, we found an interaction between time and group on initiation time of the reaction time task, since it increased in overreached athletes after the overload period (246+/-24 to 264+/-26 ms, p<0.05), while it remained unchanged in well-trained participants. Participants made very few anticipation errors, whatever the group or the period (error rate <2%).We concluded that an unaccustomed increase in training volume which is accompanied by a decrement in physical performance induces a deterioration of some executive functions. Georg Thieme Verlag KG Stuttgart . New York.

  11. Functional illiteracy in Slovenia

    Directory of Open Access Journals (Sweden)

    Ester Možina

    1999-12-01

    Full Text Available The author draws attention to the fact that, in determining functional illiteracy, there remain many terminological disagreements and diverse opinions regarding illiteracy. Furthermore, there are also different methods for measuring writing abilities, thus leading to disparate results. The introductory section presents the dilemmas relating to the term of functional illiteracy, while the second part is concerned with the various methods for measuring literacy. Thus, the author also critically assesses the research studies aimed at evaluating the scope of literacy amongst adults in Slovenia during the past decade. ln this paper, she has adopted a methodology which would not determine what is functional and what is not in our society, in order to avoid limiting the richness of individual writing praxis.

  12. Functional studies using NMR

    International Nuclear Information System (INIS)

    McCready, V.R.; Leach, M.O.; Sutton; Ell, P.

    1986-01-01

    The object of this book is to discuss and evaluate an area of Nuclear Magnetic Resonance which to date has been less emphasized than it might be, namely the use of NMR for functional studies. The book commences with a discussion of the areas in which the NMR techniques might be needed due to deficiencies in other techniques. The physics of NMR especially relating to functional measurement are then explained. Technical factors in producing functional images are discussed and the use of paramagnetic substances for carrying out flow studies are detailed. Particular attention is paid to specific studies in the various organs. The book ends with a survey of imaging in each organ and the relation of NMR images to other techniques such as ultrasound, nuclear medicine and X-rays

  13. Quantal density functional theory

    CERN Document Server

    Sahni, Viraht

    2016-01-01

    This book deals with quantal density functional theory (QDFT) which is a time-dependent local effective potential theory of the electronic structure of matter. The treated time-independent QDFT constitutes a special case. In the 2nd edition, the theory is extended to include the presence of external magnetostatic fields. The theory is a description of matter based on the ‘quantal Newtonian’ first and second laws which is in terms of “classical” fields that pervade all space, and their quantal sources. The fields, which are explicitly defined, are separately representative of electron correlations due to the Pauli exclusion principle, Coulomb repulsion, correlation-kinetic, correlation-current-density, and correlation-magnetic effects. The book further describes Schrödinger theory from the new physical perspective of fields and quantal sources. It also describes traditional Hohenberg-Kohn-Sham DFT, and explains via QDFT the physics underlying the various energy functionals and functional derivatives o...

  14. Protein Functionalized Nanodiamond Arrays

    Directory of Open Access Journals (Sweden)

    Liu YL

    2010-01-01

    Full Text Available Abstract Various nanoscale elements are currently being explored for bio-applications, such as in bio-images, bio-detection, and bio-sensors. Among them, nanodiamonds possess remarkable features such as low bio-cytotoxicity, good optical property in fluorescent and Raman spectra, and good photostability for bio-applications. In this work, we devise techniques to position functionalized nanodiamonds on self-assembled monolayer (SAMs arrays adsorbed on silicon and ITO substrates surface using electron beam lithography techniques. The nanodiamond arrays were functionalized with lysozyme to target a certain biomolecule or protein specifically. The optical properties of the nanodiamond-protein complex arrays were characterized by a high throughput confocal microscope. The synthesized nanodiamond-lysozyme complex arrays were found to still retain their functionality in interacting with E. coli.

  15. Choice probability generating functions

    DEFF Research Database (Denmark)

    Fosgerau, Mogens; McFadden, Daniel; Bierlaire, Michel

    2010-01-01

    This paper establishes that every random utility discrete choice model (RUM) has a representation that can be characterized by a choice-probability generating function (CPGF) with specific properties, and that every function with these specific properties is consistent with a RUM. The choice...... probabilities from the RUM are obtained from the gradient of the CPGF. Mixtures of RUM are characterized by logarithmic mixtures of their associated CPGF. The paper relates CPGF to multivariate extreme value distributions, and reviews and extends methods for constructing generating functions for applications....... The choice probabilities of any ARUM may be approximated by a cross-nested logit model. The results for ARUM are extended to competing risk survival models....

  16. Functional Programming Using F#

    DEFF Research Database (Denmark)

    Hansen, Michael Reichhardt; Rischel, Hans

    This comprehensive introduction to the principles of functional programming using F# shows how to apply basic theoretical concepts to produce succinct and elegant programs. It demonstrates the role of functional programming in a wide spectrum of applications including databases and systems....... Coverage also includes advanced features in the .NET library, the imperative features of F# and topics such as text processing, sequences, computation expressions and asynchronous computation. With a broad spectrum of examples and exercises, the book is perfect for courses in functional programming...... and for self-study. Enhancing its use as a text is an accompanying website with downloadable programs, lecture slides, a mini-projects and links to further F# sources....

  17. Spaces of continuous functions

    CERN Document Server

    Groenewegen, G L M

    2016-01-01

    The space C(X) of all continuous functions on a compact space X carries the structure of a normed vector space, an algebra and a lattice. On the one hand we study the relations between these structures and the topology of X, on the other hand we discuss a number of classical results according to which an algebra or a vector lattice can be represented as a C(X). Various applications of these theorems are given. Some attention is devoted to related theorems, e.g. the Stone Theorem for Boolean algebras and the Riesz Representation Theorem. The book is functional analytic in character. It does not presuppose much knowledge of functional analysis; it contains introductions into subjects such as the weak topology, vector lattices and (some) integration theory.

  18. Expanding Pseudorandom Functions

    DEFF Research Database (Denmark)

    Damgård, Ivan Bjerre; Nielsen, Jesper Buus

    2002-01-01

    Given any weak pseudorandom function, we present a general and efficient technique transforming such a function to a new weak pseudorandom function with an arbitrary length output. This implies, among other things, an encryption mode for block ciphers. The mode is as efficient as known (and widely...... used) encryption modes as CBC mode and counter (CTR) mode, but is provably secure against chosen-plaintext attack (CPA) already if the underlying symmetric cipher is secure against known-plaintext attack (KPA). We prove that CBC, CTR and Jutla’s integrity aware modes do not have this property....... In particular, we prove that when using a KPA secure block cipher, then: CBC mode is KPA secure, but need not be CPA secure, Jutla’s modes need not be CPA secure, and CTR mode need not be even KPA secure. The analysis is done in a concrete security framework....

  19. Statistical wave function

    International Nuclear Information System (INIS)

    Levine, R.D.

    1988-01-01

    Statistical considerations are applied to quantum mechanical amplitudes. The physical motivation is the progress in the spectroscopy of highly excited states. The corresponding wave functions are strongly mixed. In terms of a basis set of eigenfunctions of a zeroth-order Hamiltonian with good quantum numbers, such wave functions have contributions from many basis states. The vector x is considered whose components are the expansion coefficients in that basis. Any amplitude can be written as a dagger x x. It is argued that the components of x and hence other amplitudes can be regarded as random variables. The maximum entropy formalism is applied to determine the corresponding distribution function. Two amplitudes a dagger x x and b dagger x x are independently distributed if b dagger x a = 0. It is suggested that the theory of quantal measurements implies that, in general, one can one determine the distribution of amplitudes and not the amplitudes themselves

  20. Platelet function in dogs

    DEFF Research Database (Denmark)

    Nielsen, Line A.; Zois, Nora Elisabeth; Pedersen, Henrik D.

    2007-01-01

    Background: Clinical studies investigating platelet function in dogs have had conflicting results that may be caused by normal physiologic variation in platelet response to agonists. Objectives: The objective of this study was to investigate platelet function in clinically healthy dogs of 4...... different breeds by whole-blood aggregometry and with a point-of-care platelet function analyzer (PFA-100), and to evaluate the effect of acetylsalicylic acid (ASA) administration on the results from both methods. Methods: Forty-five clinically healthy dogs (12 Cavalier King Charles Spaniels [CKCS], 12...... applied. However, the importance of these breed differences remains to be investigated. The PFA-100 method with Col + Epi as agonists, and ADP-induced platelet aggregation appear to be sensitive to ASA in dogs....

  1. Path-dependent functions

    International Nuclear Information System (INIS)

    Khrapko, R.I.

    1985-01-01

    A uniform description of various path-dependent functions is presented with the help of expansion of the type of the Taylor series. So called ''path-integrals'' and ''path-tensor'' are introduced which are systems of many-component quantities whose values are defined for arbitrary paths in coordinated region of space in such a way that they contain a complete information on the path. These constructions are considered as elementary path-dependent functions and are used instead of power monomials in the usual Taylor series. Coefficients of such an expansion are interpreted as partial derivatives dependent on the order of the differentiations or else as nonstandard cavariant derivatives called two-point derivatives. Some examples of pathdependent functions are presented.Space curvature tensor is considered whose geometrica properties are determined by the (non-transitive) translator of parallel transport of a general type. Covariant operation leading to the ''extension'' of tensor fiels is pointed out

  2. Functional bowel disease

    DEFF Research Database (Denmark)

    Rumessen, J J; Gudmand-Høyer, E

    1988-01-01

    Twenty-five patients with functional bowel disease were given fructose, sorbitol, fructose-sorbitol mixtures, and sucrose. The occurrence of malabsorption was evaluated by means of hydrogen breath tests and the gastrointestinal symptoms, if any, were recorded. One patient could not be evaluated...... because of lack of H2 production. Based on a cut-off level of 10 ppm rise of H2 concentration, malabsorption was apparent in 13 patients, in 7 of which the calculated absorption capacities were below 15 g. In contrast, in patients given 50 g of sucrose, malabsorption could not be detected. Ingestion...... with functional bowel disease. The findings may have direct influence on the dietary guidance given to a major group of patients with functional bowel disease and may make it possible to define separate entities in this disease complex....

  3. Functional digital substraction sialography

    International Nuclear Information System (INIS)

    Yudin, L.; Saidkarimova, I.

    1994-01-01

    The proposed method of functional digital substraction sialography makes possible to reduce the amount of contrast substance used, by comparison to conventional sialography. The processing of the obtained image during different phases of the contrast visualisation of the gland allows for detecting and recording eventual functional disorders. A more clear-cut visualization of subtracted contrast images against the background of the eliminated bone structures is attained. A total of 37 patients presenting various diseases of salivary glands are covered in this study. The procedure applied contributes greatly to improving the quality of diagnosing information afforded by the counter-stained image of salivary glands at reduced radiation exposure and shorter time of examination. An essential advantage is the possibility provided to disclose functional and morphological changes, especially in the early phases of the disease. 11 refs. (orig.)

  4. The function of ornaments

    DEFF Research Database (Denmark)

    Glaveanu, Vlad Petre

    2014-01-01

    of their manifold functions that integrates aesthetic and utilitarian, individual and social roles. Ornaments help us to identify and locate, tell or communicate, remind and organise our action, they guide our attention, express and individualise, can generate an experience, beautify as well as re......-present. These functions are illustrated with examples from a study of Easter egg decoration practices in northern Romania. In the end, the ‘meta-function’ of emergence is discussed and consideration is given to the spatial and temporal contexts of ornaments. Future opportunities for theorising ornamentation...

  5. Complex function theory

    CERN Document Server

    Sarason, Donald

    2007-01-01

    Complex Function Theory is a concise and rigorous introduction to the theory of functions of a complex variable. Written in a classical style, it is in the spirit of the books by Ahlfors and by Saks and Zygmund. Being designed for a one-semester course, it is much shorter than many of the standard texts. Sarason covers the basic material through Cauchy's theorem and applications, plus the Riemann mapping theorem. It is suitable for either an introductory graduate course or an undergraduate course for students with adequate preparation. The first edition was published with the title Notes on Co

  6. Nucleon structure functions

    International Nuclear Information System (INIS)

    Virchaux, M.

    1992-11-01

    The present status of experimental measurements of the nucleon structure functions is reviewed. The results from nearly all deep inelastic experiments are in good mutual agreement. Principles of the analysis of these structure function data in the framework of QCD are described. The specific features of the perturbative QCD predictions are observed in the data. This provides quantitative tests of the validity of QCD as well as determinations of the various parton distributions in the nucleon and some of the most precise measurements of the strong coupling constant αs. The future of this field of experimental physics is sketched

  7. Harmonic supergraphs. Green functions

    International Nuclear Information System (INIS)

    Galperin, A.; Ivanov, E.; Gievetsky, V.; Sokatchev, E.

    1985-01-01

    The quantization procedure in the harmonic superspace approach is worked out. Harmonic distributions are introduced and are used to construct the analytic superspace delta-functions and the Green functions for the hypermultiplet and the N=2 Yang-Mills superfields. The gauge fixing is described and the relevant Faddeev-Popov ghosts are defined. The corresponding BRST transformations are found. The harmonic superspace quantization of the N=2 gauge theory turns out to be rather simple and has many parallels with that for the standard (N=0) Yang-Mills theory. In particular, no ghosts-forghosts are needed

  8. Chromatin Structure and Function

    CERN Document Server

    Wolffe, Alan P

    1999-01-01

    The Third Edition of Chromatin: Structure and Function brings the reader up-to-date with the remarkable progress in chromatin research over the past three years. It has been extensively rewritten to cover new material on chromatin remodeling, histone modification, nuclear compartmentalization, DNA methylation, and transcriptional co-activators and co-repressors. The book is written in a clear and concise fashion, with 60 new illustrations. Chromatin: Structure and Function provides the reader with a concise and coherent account of the nature, structure, and assembly of chromatin and its active

  9. Unpolarized Structure Functions

    International Nuclear Information System (INIS)

    Christy, M.E.; Melnitchouk, W.

    2011-01-01

    Over the past decade measurements of unpolarized structure functions with unprecedented precision have significantly advanced our knowledge of nucleon structure. These have for the first time allowed quantitative tests of the phenomenon of quark-hadron duality, and provided a deeper understanding of the transition from hadron to quark degrees of freedom in inclusive scattering. Dedicated Rosenbluth-separation experiments have yielded high-precision transverse and longitudinal structure functions in regions previously unexplored, and new techniques have enabled the first glimpses of the structure of the free neutron, without contamination from nuclear effects.

  10. Quantum functional oracles

    International Nuclear Information System (INIS)

    Kim, Jinsoo; Lee, Soojoon; Chi, Dong Pyo

    2002-01-01

    The limitation on the size of quantum computers makes it important to reuse qubits for auxiliary registers even though they are entangled with others and are occupied by other computational processes. We construct a quantum algorithm that performs the functional phase rotation, which is the generalized form of the conventional conditional phase transforms, using the functional evaluation oracle. The constructed algorithm works without any a priori knowledge of the state of an auxiliary register at the beginning and it recovers the initial state of an auxiliary register at the end. This provides ample scope to choose qubits for auxiliary registers at will. (author)

  11. Early Functional Abilities

    DEFF Research Database (Denmark)

    Lorentzen, Jakob; Poulsen, Ingrid

    2005-01-01

    Early Functional Abilities (EFA), - en skala til evaluering af behandlingsforløb af svært hjerneskadede patienter i forbindelse med tidlig rehabilitering. Formål At monitorere og dokumentere rehabiliteringsforløbet for svært hjerneskadede patienter, hvor funktionsniveauet endnu ikke kan registreres...

  12. Wine and endothelial function.

    Science.gov (United States)

    Caimi, G; Carollo, C; Lo Presti, R

    2003-01-01

    In recent years many studies have focused on the well-known relationship between wine consumption and cardiovascular risk. Wine exerts its protective effects through various changes in lipoprotein profile, coagulation and fibrinolytic cascades, platelet aggregation, oxidative mechanisms and endothelial function. The last has earned more attention for its implications in atherogenesis. Endothelium regulates vascular tone by a delicate balancing among vasorelaxing (nitric oxide [NO]) and vasoconstrincting (endothelins) factors produced by endothelium in response to various stimuli. In rat models, wine and other grape derivatives exerted an endothelium-dependent vasorelaxing capacity especially associated with the NO-stimulating activity of their polyphenol components. In experimental conditions, reservatrol (a stilbene polyphenol) protected hearts and kidneys from ischemia-reperfusion injury through antioxidant activity and upregulation of NO production. Wine polyphenols are also able to induce the expression of genes involved in the NO pathway within the arterial wall. The effects of wine on endothelial function in humans are not yet clearly understood. A favorable action of red wine or dealcoholized wine extract or purple grape juice on endothelial function has been observed by several authors, but discrimination between ethanol and polyphenol effects is controversial. It is, however likely that regular and prolonged moderate wine drinking positively affects endothelial function. The beneficial effects of wine on cardiovascular health are greater if wine is associated with a healthy diet. The most recent nutritional and epidemiologic studies show that the ideal diet closely resembles the Mediterranean diet.

  13. Fabrics in Function

    DEFF Research Database (Denmark)

    Bang, Anne Louise

    2007-01-01

    sensing of fabrics in function. It is proposed that tactile and visual sensing of fabrics is a way to investigate and express emotional utility values. The further purpose is to use experiments with repertory grid models as part of the mapping of the entire research project and also as a basis...

  14. DNA: Structure and function

    DEFF Research Database (Denmark)

    Sinden, Richard R.; E. Pearson, Christopher; N. Potaman, Vladimir

    1998-01-01

    This chapter discusses the structure and function of DNA. DNA occupies a critical role in cells, because it is the source of all intrinsic genetic information. Chemically, DNA is a very stable molecule, a characteristic important for a macromolecule that may have to persist in an intact form...

  15. Brown adipocyte function

    DEFF Research Database (Denmark)

    Winther, Sally

    . The first part of this thesis explores this by identifying and investigating two novel kinase regulators of brown adipocyte function. Study 1 demonstrates that spleen tyrosine kinase is a hitherto undescribed regulator of brown adipocyte differentiation and activation. Study 2 identifies glycogen synthase...

  16. Nonlinear functional analysis

    CERN Document Server

    Deimling, Klaus

    1985-01-01

    topics. However, only a modest preliminary knowledge is needed. In the first chapter, where we introduce an important topological concept, the so-called topological degree for continuous maps from subsets ofRn into Rn, you need not know anything about functional analysis. Starting with Chapter 2, where infinite dimensions first appear, one should be familiar with the essential step of consider­ ing a sequence or a function of some sort as a point in the corresponding vector space of all such sequences or functions, whenever this abstraction is worthwhile. One should also work out the things which are proved in § 7 and accept certain basic principles of linear functional analysis quoted there for easier references, until they are applied in later chapters. In other words, even the 'completely linear' sections which we have included for your convenience serve only as a vehicle for progress in nonlinearity. Another point that makes the text introductory is the use of an essentially uniform mathematical languag...

  17. Functional Group Analysis.

    Science.gov (United States)

    Smith, Walter T., Jr.; Patterson, John M.

    1984-01-01

    Literature on analytical methods related to the functional groups of 17 chemical compounds is reviewed. These compounds include acids, acid azides, alcohols, aldehydes, ketones, amino acids, aromatic hydrocarbons, carbodiimides, carbohydrates, ethers, nitro compounds, nitrosamines, organometallic compounds, peroxides, phenols, silicon compounds,…

  18. Empirical microeconomics action functionals

    Science.gov (United States)

    Baaquie, Belal E.; Du, Xin; Tanputraman, Winson

    2015-06-01

    A statistical generalization of microeconomics has been made in Baaquie (2013), where the market price of every traded commodity, at each instant of time, is considered to be an independent random variable. The dynamics of commodity market prices is modeled by an action functional-and the focus of this paper is to empirically determine the action functionals for different commodities. The correlation functions of the model are defined using a Feynman path integral. The model is calibrated using the unequal time correlation of the market commodity prices as well as their cubic and quartic moments using a perturbation expansion. The consistency of the perturbation expansion is verified by a numerical evaluation of the path integral. Nine commodities drawn from the energy, metal and grain sectors are studied and their market behavior is described by the model to an accuracy of over 90% using only six parameters. The paper empirically establishes the existence of the action functional for commodity prices that was postulated to exist in Baaquie (2013).

  19. Functional System Dynamics

    NARCIS (Netherlands)

    Ligterink, N.E.

    2007-01-01

    Functional system dynamics is the analysis, modelling, and simulation of continuous systems usually described by partial differential equations. From the infinite degrees of freedom of such systems only a finite number of relevant variables have to be chosen for a practical model description. The

  20. Objectification and Semiotic Function

    Science.gov (United States)

    Santi, George

    2011-01-01

    The objective of this paper is to study students' difficulties when they have to ascribe the same meaning to different representations of the same mathematical object. We address two theoretical tools that are at the core of Radford's cultural semiotic and Godino's onto-semiotic approaches: objectification and the semiotic function. The analysis…

  1. Cobham recursive set functions

    Czech Academy of Sciences Publication Activity Database

    Beckmann, A.; Buss, S.; Friedman, S.-D.; Müller, M.; Thapen, Neil

    2016-01-01

    Roč. 167, č. 3 (2016), s. 335-369 ISSN 0168-0072 R&D Projects: GA ČR GBP202/12/G061 Institutional support: RVO:67985840 Keywords : set function * polynomial time * Cobham recursion Subject RIV: BA - General Mathematics Impact factor: 0.647, year: 2016 http://www.sciencedirect.com/science/article/pii/S0168007215001293

  2. Relativistic Wigner functions

    Directory of Open Access Journals (Sweden)

    Bialynicki-Birula Iwo

    2014-01-01

    Full Text Available Original definition of the Wigner function can be extended in a natural manner to relativistic domain in the framework of quantum field theory. Three such generalizations are described. They cover the cases of the Dirac particles, the photon, and the full electromagnetic field.

  3. Production Functions Behaving Badly

    DEFF Research Database (Denmark)

    Fredholm, Thomas

    This paper reconsiders Anwar Shaikh's critique of the neoclassical theory of growth and distribution based on its use of aggregate production functions. This is done by reconstructing and extending Franklin M. Fisher's 1971 computer simulations, which Shaikh used to support his critique. Together...

  4. Modifiable Combining Functions

    OpenAIRE

    Cohen, Paul; Shafer, Glenn; Shenoy, Prakash P.

    2013-01-01

    Modifiable combining functions are a synthesis of two common approaches to combining evidence. They offer many of the advantages of these approaches and avoid some disadvantages. Because they facilitate the acquisition, representation, explanation, and modification of knowledge about combinations of evidence, they are proposed as a tool for knowledge engineers who build systems that reason under uncertainty, not as a normative theory of evidence.

  5. Functional abdominal pain.

    Science.gov (United States)

    Grover, Madhusudan; Drossman, Douglas A

    2010-10-01

    Functional abdominal pain syndrome (FAPS) is a relatively less common functional gastrointestinal (GI) disorder defined by the presence of constant or frequently recurring abdominal pain that is not associated with eating, change in bowel habits, or menstrual periods (Drossman Gastroenterology 130:1377-1390, 2006), which points to a more centrally targeted (spinal and supraspinal) basis for the symptoms. However, FAPS is frequently confused with irritable bowel syndrome and other functional GI disorders in which abdominal pain is associated with eating and bowel movements. FAPS also differs from chronic abdominal pain associated with entities such as chronic pancreatitis or chronic inflammatory bowel disease, in which the pain is associated with peripherally acting factors (eg, gut inflammation or injury). Given the central contribution to the pain experience, concomitant psychosocial disturbances are common and strongly influence the clinical expression of FAPS, which also by definition is associated with loss of daily functioning. These factors make it critical to use a biopsychosocial construct to understand and manage FAPS, because gut-directed treatments are usually not successful in managing this condition.

  6. Micrononcasual Euclidean wave functions

    International Nuclear Information System (INIS)

    Enatsu, H.; Takenaka, A.; Okazaki, M.

    1978-01-01

    A theory which describes the internal attributes of hadrons in terms of space-time wave functions is presented. In order to develop the theory on the basis of a rather realistic model, covariant wave equations are first derived for the deuteron, in which the co-ordinates of the centre of mass of two nucleons can be defined unambiguously. Then the micro-noncasual behaviour of virtual mesons mediating between the two nucleons is expressed by means of wave functions depending only on the relative Euclidean co-ordinates with respect to the centre of mass of the two nucleons; the wave functions are assumed to obey the 0 4 and SU 2 x SU 2 groups. The properties of the wave functions under space inversion, time reversal and particle-antiparticle conjugation are investigated. It is found that the internal attributes of the mesons, such as spin, isospin, strangeness, intrinsic parity, charge parity and G-parity are explained consistently. The theory is applicable also to the case of baryons

  7. Functional ingredients from microalgae

    NARCIS (Netherlands)

    Buono, S.; Langellotti, A.L.; Martello, A.; Rinna, F.; Fogliano, V.

    2014-01-01

    A wide variety of natural sources are under investigation to evaluate their possible use for new functional ingredient formulation. Some records attested the traditional and ancient use of wild harvested microalgae as human food but their cultivation for different purposes started about 40 years

  8. Update on Functional Heartburn

    Science.gov (United States)

    Yamasaki, Takahisa; O’Neil, Jessica

    2017-01-01

    The definition of functional heartburn has been refined over the years. It is currently described, based upon Rome IV criteria, as typical heartburn symptoms in the presence of normal upper endoscopy findings (including normal biopsies), normal esophageal pH testing, and a negative association between symptoms and reflux events. Functional heartburn is very common, affecting women more than men, and with reflux hypersensitivity makes up the majority of heartburn patients who fail twice-daily proton pump inhibitor therapy. These disorders overlap with other functional gastrointestinal disorders and are often accompanied by psychological comorbidities. Diagnosis is made by using endoscopy with esophageal biopsies, wireless pH capsule, pH-impedance monitoring, and high-resolution esophageal manometry. Additional diagnostic tools that may be of value include magnification endoscopy, chromoendoscopy, narrow-band imaging, autofluorescence imaging, mucosal impedance, impedance baseline values, and histopathology scores. Functional heartburn is primarily treated with neuromodulators. Psychological intervention and complementary and alternative medicine may also play important roles in the treatment of these patients. PMID:29339948

  9. Efficient Generic Functional Programming

    NARCIS (Netherlands)

    Alimarine, A.; Smetsers, J.E.W.

    2005-01-01

    Generic functions are defined by induction on the structural representation of types. As a consequence, by defining just a single generic operation, one acquires this operation over any particular data type. An instance on a specific type is generated by interpretation of the type's structure. A

  10. Optimizing Generic Functions

    NARCIS (Netherlands)

    Alimarine, A.; Smetsers, J.E.W.

    2004-01-01

    Generic functions are defined by induction on the structural representation of types. As a consequence, by defining just a single generic operation, one acquires this operation over any particular type. An instance on a specific type is generated by interpretation of the type's structure. A direct

  11. Logarithmic-function generator

    Science.gov (United States)

    Caron, P. R.

    1975-01-01

    Solid-state logarithmic-function generator is compact and provides improved accuracy. Generator includes a stable multivibrator feeding into RC circuit. Resulting exponentially decaying voltage is compared with input signal. Generator output is proportional to time required for exponential voltage to decay from preset reference level to level of input signal.

  12. Functional Communication Training

    Science.gov (United States)

    Durand, V. Mark; Moskowitz, Lauren

    2015-01-01

    Thirty years ago, the first experimental demonstration was published showing that educators could improve significant challenging behavior in children with disabilities by replacing these behaviors with forms of communication that served the same purpose, a procedure called functional communication training (FCT). Since the publication of that…

  13. Generalized elementary functions

    Czech Academy of Sciences Publication Activity Database

    Monteiro, Giselle Antunes; Slavík, A.

    2014-01-01

    Roč. 411, č. 2 (2014), s. 838-852 ISSN 0022-247X Institutional support: RVO:67985840 Keywords : elementary functions * Kurzweil-Stieltjes integral * generalized linear ordinary differential equations * time scale calculus Subject RIV: BA - General Mathematics Impact factor: 1.120, year: 2014 http://www.sciencedirect.com/science/article/pii/S0022247X13009141

  14. Executive functions in synesthesia

    NARCIS (Netherlands)

    Rouw, Romke; van Driel, Joram; Knip, Koen; Richard Ridderinkhof, K.

    2013-01-01

    In grapheme-color synesthesia, a number or letter can evoke two different and possibly conflicting (real and synesthetic) color sensations at the same time. In this study, we investigate the relationship between synesthesia and executive control functions. First, no general skill differences were

  15. Mars Sample Handling Functionality

    Science.gov (United States)

    Meyer, M. A.; Mattingly, R. L.

    2018-04-01

    The final leg of a Mars Sample Return campaign would be an entity that we have referred to as Mars Returned Sample Handling (MRSH.) This talk will address our current view of the functional requirements on MRSH, focused on the Sample Receiving Facility (SRF).

  16. Laboratory Density Functionals

    OpenAIRE

    Giraud, B. G.

    2007-01-01

    We compare several definitions of the density of a self-bound system, such as a nucleus, in relation with its center-of-mass zero-point motion. A trivial deconvolution relates the internal density to the density defined in the laboratory frame. This result is useful for the practical definition of density functionals.

  17. Automate functional testing

    Directory of Open Access Journals (Sweden)

    Ramesh Kalindri

    2014-06-01

    Full Text Available Currently, software engineers are increasingly turning to the option of automating functional tests, but not always have successful in this endeavor. Reasons range from low planning until over cost in the process. Some principles that can guide teams in automating these tests are described in this article.

  18. The functionality of creativity

    NARCIS (Netherlands)

    Sligte, D.J.

    2013-01-01

    This dissertation is about the functionality of creativity. Why do people invest time and effort in being creative? Being creative is inherently risky, as you need to come up with something new that departs from what is already known, and there is a risk of ridicule, being singled out, or simply

  19. Automatic Functional Harmonic Analysis

    NARCIS (Netherlands)

    de Haas, W.B.; Magalhães, J.P.; Wiering, F.; Veltkamp, R.C.

    2013-01-01

    Music scholars have been studying tonal harmony intensively for centuries, yielding numerous theories and models. Unfortunately, a large number of these theories are formulated in a rather informal fashion and lack mathematical precision. In this article we present HarmTrace, a functional model of

  20. Functional System Dynamics

    OpenAIRE

    Ligterink, N.E.

    2007-01-01

    Functional system dynamics is the analysis, modelling, and simulation of continuous systems usually described by partial differential equations. From the infinite degrees of freedom of such systems only a finite number of relevant variables have to be chosen for a practical model description. The proper input and output of the system are an important part of the relevant variables.

  1. Functions of public relations

    OpenAIRE

    Baranov G. V.

    2016-01-01

    the article reveals the importance of communication with the public in the implementation of human rights and the ideals of mankind; characterized by the specificity of public relations in the information culture of belief; PR functions are explained on the criterion of optimization of activity of social interactions on the basis of cultural ideals.

  2. Semiclassical multicomponent wave function

    NARCIS (Netherlands)

    Mostovoy, M.V.

    A consistent method for obtaining the semiclassical multicomponent wave function for any value of adiabatic parameter is discussed and illustrated by examining the motion of a neutral particle in a nonuniform magnetic field. The method generalizes the Bohr-Sommerfeld quantization rule to

  3. Mapping functional connectivity

    Science.gov (United States)

    Peter Vogt; Joseph R. Ferrari; Todd R. Lookingbill; Robert H. Gardner; Kurt H. Riitters; Katarzyna Ostapowicz

    2009-01-01

    An objective and reliable assessment of wildlife movement is important in theoretical and applied ecology. The identification and mapping of landscape elements that may enhance functional connectivity is usually a subjective process based on visual interpretations of species movement patterns. New methods based on mathematical morphology provide a generic, flexible,...

  4. Comparisons of power transfer functions and flow transfer functions

    International Nuclear Information System (INIS)

    Grimm, K.N.; Meneghetti, D.

    1987-01-01

    Transfer functions may be used to calculate component feedbacks or temperature increments by convolution of the transfer function with the appropriate fractional change in system-quantity. Power-change transfer functions have been reported. The corresponding flow transfer functions for this case, and comparison with the power transfer functions, are reported here. Results of feedback simulation of ramped flow transients using flow transfer functions are also described

  5. Completely monotonic functions related to logarithmic derivatives of entire functions

    DEFF Research Database (Denmark)

    Pedersen, Henrik Laurberg

    2011-01-01

    The logarithmic derivative l(x) of an entire function of genus p and having only non-positive zeros is represented in terms of a Stieltjes function. As a consequence, (-1)p(xml(x))(m+p) is a completely monotonic function for all m ≥ 0. This generalizes earlier results on complete monotonicity...... of functions related to Euler's psi-function. Applications to Barnes' multiple gamma functions are given....

  6. EXECUTIVE FUNCTIONING IN SCHIZOPHRENIA

    Directory of Open Access Journals (Sweden)

    Gricel eOrellana

    2013-06-01

    Full Text Available The executive function (EF is a set of abilities, which allows us to invoke voluntary control of our behavioral responses. These functions enable human beings to develop and carry out plans, make up analogies, obey social rules, solve problems, adapt to unexpected circumstances, do many tasks simultaneously and locate episodes in time and place. EF includes divided attention and sustained attention, working memory, set-shifting, flexibility, planning and the regulation of goal directed behavior and can be defined as a brain function underlying the human faculty to act or think not only in reaction to external events but also in relation with internal goals and states. EF is mostly associated with dorsolateral prefrontal cortex (PFC. Besides EF, PFC is involved in self-regulation of behavior, i.e. the ability to regulate behavior according to internal goals and constraints, particularly in less structured situations. Self-regulation of behavior is subtended by ventral medial /orbital PFC. Impairment of EF is one of the most commonly observed deficits in schizophrenia through the various disease stages. Impairment in tasks measuring conceptualization, planning, cognitive flexibility, verbal fluency, ability to solve complex problems and working memory occur in schizophrenia. Disorders detected by executive tests are consistent with evidence from functional neuroimaging, which have shown PFC dysfunction in patients while performing these kinds of tasks. Schizophrenics also exhibit deficit in odor identifying, decision-making and self-regulation of behavior suggesting dysfunction of the orbital PFC. However, impairment in executive tests is explained by dysfunction of prefronto-striato-thalamic, prefronto-parietal and prefronto-temporal neural networks mainly. Disorders in executive functions may be considered central facts with respect to schizophrenia and it has been suggested that negative symptoms may be explained by that executive dysfunction.

  7. Pulmonary function in space

    Science.gov (United States)

    West, J. B.; Elliott, A. R.; Guy, H. J.; Prisk, G. K.

    1997-01-01

    The lung is exquisitely sensitive to gravity, and so it is of interest to know how its function is altered in the weightlessness of space. Studies on National Aeronautics and Space Administration (NASA) Spacelabs during the last 4 years have provided the first comprehensive data on the extensive changes in pulmonary function that occur in sustained microgravity. Measurements of pulmonary function were made on astronauts during space shuttle flights lasting 9 and 14 days and were compared with extensive ground-based measurements before and after the flights. Compared with preflight measurements, cardiac output increased by 18% during space flight, and stroke volume increased by 46%. Paradoxically, the increase in stroke volume occurred in the face of reductions in central venous pressure and circulating blood volume. Diffusing capacity increased by 28%, and the increase in the diffusing capacity of the alveolar membrane was unexpectedly large based on findings in normal gravity. The change in the alveolar membrane may reflect the effects of uniform filling of the pulmonary capillary bed. Distributions of blood flow and ventilation throughout the lung were more uniform in space, but some unevenness remained, indicating the importance of nongravitational factors. A surprising finding was that airway closing volume was approximately the same in microgravity and in normal gravity, emphasizing the importance of mechanical properties of the airways in determining whether they close. Residual volume was unexpectedly reduced by 18% in microgravity, possibly because of uniform alveolar expansion. The findings indicate that pulmonary function is greatly altered in microgravity, but none of the changes observed so far will apparently limit long-term space flight. In addition, the data help to clarify how gravity affects pulmonary function in the normal gravity environment on Earth.

  8. Educating executive function.

    Science.gov (United States)

    Blair, Clancy

    2017-01-01

    Executive functions are thinking skills that assist with reasoning, planning, problem solving, and managing one's life. The brain areas that underlie these skills are interconnected with and influenced by activity in many different brain areas, some of which are associated with emotion and stress. One consequence of the stress-specific connections is that executive functions, which help us to organize our thinking, tend to be disrupted when stimulation is too high and we are stressed out, or too low when we are bored and lethargic. Given their central role in reasoning and also in managing stress and emotion, scientists have conducted studies, primarily with adults, to determine whether executive functions can be improved by training. By and large, results have shown that they can be, in part through computer-based videogame-like activities. Evidence of wider, more general benefits from such computer-based training, however, is mixed. Accordingly, scientists have reasoned that training will have wider benefits if it is implemented early, with very young children as the neural circuitry of executive functions is developing, and that it will be most effective if embedded in children's everyday activities. Evidence produced by this research, however, is also mixed. In sum, much remains to be learned about executive function training. Without question, however, continued research on this important topic will yield valuable information about cognitive development. WIREs Cogn Sci 2017, 8:e1403. doi: 10.1002/wcs.1403 For further resources related to this article, please visit the WIREs website. © 2016 Wiley Periodicals, Inc.

  9. Quasi-extended asymptotic functions

    International Nuclear Information System (INIS)

    Todorov, T.D.

    1979-01-01

    The class F of ''quasi-extended asymptotic functions'' is introduced. It contains all extended asymptotic functions as well as some new asymptotic functions very similar to the Schwartz distributions. On the other hand, every two quasiextended asymptotic functions can be multiplied as opposed to the Schwartz distributions; in particular, the square delta 2 of an asymptotic function delta similar to Dirac's delta-function, is constructed as an example

  10. The Relationships between Weight Functions, Geometric Functions,and Compliance Functions in Linear Elastic Fracture Mechanics

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, Rong [Univ. of California, Berkeley, CA (United States)

    2007-01-01

    Linear elastic fracture mechanics is widely used in industry because it established simple and explicit relationships between the permissible loading conditions and the critical crack size that is allowed in a structure. Stress intensity factors are the above-mentioned functional expressions that relate load with crack size through geometric functions or weight functions. Compliance functions are to determine the crack/flaw size in a structure when optical inspection is inconvenient. As a result, geometric functions, weight functions and compliance functions have been intensively studied to determine the stress intensity factor expressions for different geometries. However, the relations between these functions have received less attention. This work is therefore to investigate the intrinsic relationships between these functions. Theoretical derivation was carried out and the results were verified on single-edge cracked plate under tension and bending. It is found out that the geometric function is essentially the non-dimensional weight function at the loading point. The compliance function is composed of two parts: a varying part due to crack extension and a constant part from the intact structure if no crack exists. The derivative of the compliance function at any location is the product of the geometric function and the weight function at the evaluation point. Inversely, the compliance function can be acquired by the integration of the product of the geometric function and the weight function with respect to the crack size. The integral constant is just the unchanging compliance from the intact structure. Consequently, a special application of the relations is to obtain the compliance functions along a crack once the geometric function and weight functions are known. Any of the three special functions can be derived once the other two functions are known. These relations may greatly simplify the numerical process in obtaining either geometric functions, weight

  11. Skin barrier function

    DEFF Research Database (Denmark)

    2016-01-01

    Renowned experts present the latest knowledge Although a very fragile structure, the skin barrier is probably one of the most important organs of the body. Inward/out it is responsible for body integrity and outward/in for keeping microbes, chemicals, and allergens from penetrating the skin. Since...... the role of barrier integrity in atopic dermatitis and the relationship to filaggrin mutations was discovered a decade ago, research focus has been on the skin barrier, and numerous new publications have become available. This book is an interdisciplinary update offering a wide range of information...... on the subject. It covers new basic research on skin markers, including results on filaggrin and on methods for the assessment of the barrier function. Biological variation and aspects of skin barrier function restoration are discussed as well. Further sections are dedicated to clinical implications of skin...

  12. Ramanujan's theta functions

    CERN Document Server

    Cooper, Shaun

    2017-01-01

    Theta functions were studied extensively by Ramanujan. This book provides a systematic development of Ramanujan’s results and extends them to a general theory. The author’s treatment of the subject is comprehensive, providing a detailed study of theta functions and modular forms for levels up to 12. Aimed at advanced undergraduates, graduate students, and researchers, the organization, user-friendly presentation, and rich source of examples, lends this book to serve as a useful reference, a pedagogical tool, and a stimulus for further research. Topics, especially those discussed in the second half of the book, have been the subject of much recent research; many of which are appearing in book form for the first time. Further results are summarized in the numerous exercises at the end of each chapter.

  13. Functional Esophageal Disorders.

    Science.gov (United States)

    Aziz, Qasim; Fass, Ronnie; Gyawali, C Prakash; Miwa, Hiroto; Pandolfino, John E; Zerbib, Frank

    2016-02-15

    Functional esophageal disorders consist of a disease category that present with esophageal symptoms (heartburn, chest pain, dysphagia, globus) not explained by mechanical obstruction (stricture, tumor, eosinophilic esophagitis), major motor disorders (achalasia, EGJ outflow obstruction, absent contractility, distal esophageal spasm, jackhammer esophagus), or gastroesophageal reflux disease (GERD). While mechanisms responsible are unclear, it is theorized that visceral hypersensitivity and hypervigilance play an important role in symptom generation, in the context of normal or borderline function. Treatments directed at improving borderline motor dysfunction or reducing reflux burden to sub-normal levels have limited success in symptom improvement. In contrast, strategies focused on modulating peripheral triggering and central perception are mechanistically viable and clinically meaningful. However, outcome data from these treatment options are limited. Future research needs to focus on understanding mechanisms underlying visceral hypersensitivity and hypervigilance so that appropriate targets and therapies can be developed. Copyright © 2016 AGA Institute. Published by Elsevier Inc. All rights reserved.

  14. Density functional theory

    International Nuclear Information System (INIS)

    Das, M.P.

    1984-07-01

    The state of the art of the density functional formalism (DFT) is reviewed. The theory is quantum statistical in nature; its simplest version is the well-known Thomas-Fermi theory. The DFT is a powerful formalism in which one can treat the effect of interactions in inhomogeneous systems. After some introductory material, the DFT is outlined from the two basic theorems, and various generalizations of the theorems appropriate to several physical situations are pointed out. Next, various approximations to the density functionals are presented and some practical schemes, discussed; the approximations include an electron gas of almost constant density and an electron gas of slowly varying density. Then applications of DFT in various diverse areas of physics (atomic systems, plasmas, liquids, nuclear matter) are mentioned, and its strengths and weaknesses are pointed out. In conclusion, more recent developments of DFT are indicated

  15. Differentiation of real functions

    CERN Document Server

    Bruckner, Andrew

    1994-01-01

    Topics related to the differentiation of real functions have received considerable attention during the last few decades. This book provides an efficient account of the present state of the subject. Bruckner addresses in detail the problems that arise when dealing with the class \\Delta ' of derivatives, a class that is difficult to handle for a number of reasons. Several generalized forms of differentiation have assumed importance in the solution of various problems. Some generalized derivatives are excellent substitutes for the ordinary derivative when the latter is not known to exist; others are not. Bruckner studies generalized derivatives and indicates "geometric" conditions that determine whether or not a generalized derivative will be a good substitute for the ordinary derivative. There are a number of classes of functions closely linked to differentiation theory, and these are examined in some detail. The book unifies many important results from the literature as well as some results not previously pub...

  16. Functionalization of Carbon Nanotubes

    Science.gov (United States)

    Khare, Bishun N. (Inventor); Meyyappan, Meyya (Inventor)

    2009-01-01

    Method and system for functionalizing a collection of carbon nanotubes (CNTs). A selected precursor gas (e.g., H2 or F2 or CnHm) is irradiated to provide a cold plasma of selected target species particles, such as atomic H or F, in a first chamber. The target species particles are d irected toward an array of CNTs located in a second chamber while suppressing transport of ultraviolet radiation to the second chamber. A CNT array is functionalized with the target species particles, at or below room temperature, to a point of saturation, in an exposure time interval no longer than about 30 sec. *Discrimination against non-target species is provided by (i) use of a target species having a lifetime that is much greater than a lifetime of a non-target species and/or (2) use of an applied magnetic field to discriminate between charged particle trajectories for target species and for non-target species.

  17. Functional abdominal pain syndrome.

    Science.gov (United States)

    Clouse, Ray E; Mayer, Emeran A; Aziz, Qasim; Drossman, Douglas A; Dumitrascu, Dan L; Mönnikes, Hubert; Naliboff, Bruce D

    2006-04-01

    Functional abdominal pain syndrome (FAPS) differs from the other functional bowel disorders; it is less common, symptoms largely are unrelated to food intake and defecation, and it has higher comorbidity with psychiatric disorders. The etiology and pathophysiology are incompletely understood. Because FAPS likely represents a heterogeneous group of disorders, peripheral neuropathic pain mechanisms, alterations in endogenous pain modulation systems, or both may be involved in any one patient. The diagnosis of FAPS is made on the basis of positive symptom criteria and a longstanding history of symptoms; in the absence of alarm symptoms, an extensive diagnostic evaluation is not required. Management is based on a therapeutic physician-patient relationship and empirical treatment algorithms using various classes of centrally acting drugs, including antidepressants and anticonvulsants. The choice, dose, and combination of drugs are influenced by psychiatric comorbidities. Psychological treatment options include psychotherapy, relaxation techniques, and hypnosis. Refractory FAPS patients may benefit from a multidisciplinary pain clinic approach.

  18. Ego functions in epilepsy

    DEFF Research Database (Denmark)

    Sørensen, A S; Hansen, H; Høgenhaven, H

    1988-01-01

    Two groups of epilepsy patients (28 patients with temporal lobe epilepsy and 15 patients with primary generalized epilepsy) entered a study of personality traits related to epilepsy, based on a modification of Bellak's semistructured interview for assessment of ego strength. Two groups of subjects...... than 15 years when the disease began. The number of anticonvulsants administered did not influence the results. No difference on adaptive level of ego functioning was found between the group with primary generalized epilepsy and the group with temporal lobe epilepsy. Similarly, the temporal lobe...... served as controls: 15 patients with a non-neurological but relapsing disorder, psoriasis, and 15 healthy volunteers. Compared with the group of healthy volunteers, a decreased adaptive level of ego functioning was found in the epilepsy groups, regardless of seizure types and EEG findings, and...

  19. Functional foods in Europe

    DEFF Research Database (Denmark)

    Bech-Larsen, Tino; Scholderer, Joachim

    2007-01-01

    reading of the main principles of the harmonized regulation COM/2003/0424, this situation is about to change. This article reviews the regulatory aspects, the results of consumer research and the marketing strategies regarding the use of health claims for functional foods in Europe, and it comments......The fact that the European markets for functional foods generally are less developed, compared to the US and the Japanese markets, has often been attributed to a restrictive and inconsistent health claim legislation in and between the European countries. With the European Parliament's second...... on the lack of correspondence between the new regulation and the marketing experiences and research as regard consumer reactions to health claims....

  20. Density-Functional formalism

    International Nuclear Information System (INIS)

    Szasz, L.; Berrios-Pagan, I.; McGinn, G.

    1975-01-01

    A new Density-Functional formula is constructed for atoms. The kinetic energy of the electron is divided into two parts: the kinetic self-energy and the orthogonalization energy. Calculations were made for the total energies of neutral atoms, positive ions and for the He isoelectronic series. For neutral atoms the results match the Hartree-Fock energies within 1% for atoms with N 36 the results generally match the HF energies within 0.1%. For positive ions the results are fair; for the molecular applications a simplified model is developed in which the kinetic energy consists of the Weizsaecker term plus the Fermi energy reduced by a continuous function. (orig.) [de

  1. Pancreatic exocrine function testing

    International Nuclear Information System (INIS)

    Goff, J.S.

    1981-01-01

    It is important to understand which pancreatic function tests are available and how to interpret them when evaluating patients with malabsorption. Available direct tests are the secretin stimulation test, the Lundh test meal, and measurement of serum or fecal enzymes. Indirect tests assess pancreatic exocrine function by measuring the effect of pancreatic secretion on various nutrients. These include triglycerides labeled with carbon 14, cobalamin labeled with cobalt 57 and cobalt 58, and para-aminobenzoic acid bound to a dipeptide. Of all these tests the secretin stimulation test is the most accurate and reliable if done by experienced personnel. However, the indirect tests are simpler to do and appear to be comparable to the secretin test at detecting pancreatic exocrine insufficiency. These indirect tests are becoming clinically available and clinicians should familiarize themselves with the strengths and weaknesses of each

  2. Functional studies using NMR

    International Nuclear Information System (INIS)

    McCready, V.R.; Leach, M.; Ell, P.J.

    1987-01-01

    This volume is based on a series of lectures delivered at a one-day teaching symposium on functional and metabolic aspects of NMR measurements held at the Middlesex Hospital Medical School on 1st September 1985 as a part of the European Nuclear Medicine Society Congress. Currently the major emphasis in medical NMR in vivo is on its potential to image and display abnormalities in conventional radiological images, providing increased contrast between normal and abnormal tissue, improved definition of vasculature, and possibly an increased potential for differential diagnosis. Although these areas are undeniably of major importance, it is probable that NMR will continue to complement conventional measurement methods. The major potential benefits to be derived from in vivo NMR measurements are likely to arise from its use as an instrument for functional and metabolic studies in both clinical research and in the everyday management of patients. It is to this area that this volume is directed

  3. Towards the Innovation Function

    Directory of Open Access Journals (Sweden)

    Paulo Antônio Zawislak

    2008-12-01

    Full Text Available This paper explores the main elements that influence innovation and the relationships among them. It is pointed out that innovation results from an entrepreneurial action inside an established institutional context, sustained by resources, abilities and competences and with the support of the necessary financial capital. Therefore, it is proposed that innovation is a function (just as the microeconomic production function composed of entrepreneurship, institutions, capabilities and capital. Each one of these elements is explored individually, so that later the relationships among them can be analyzed. It is still suggested that the size of the firm is a moderator in the relationship between these elements and innovation. The study’s contribution it is the development of a conceptual model.

  4. The Function of Sleep

    Directory of Open Access Journals (Sweden)

    Daniel A. Barone

    2015-06-01

    Full Text Available The importance of sleep can be ascertained by noting the effects of its loss, which tends to be chronic and partial, on cognition, mood, alertness, and overall health. Many theories have been put forth to explain the function of sleep in humans, including proposals based on energy conservation, ecological adaptations, neurocognitive function, neural plasticity, nervous system and physical health, and performance. Most account for only a portion of sleep behavior and few are based on strong experimental support. In this review, we present theories proposing why sleep is necessary and supporting data demonstrating the effects of inadequate sleep, with the intention of gleaning further information as to its necessity, which remains one of the most perplexing mysteries in biology.

  5. Auroal electron distribution function

    International Nuclear Information System (INIS)

    Kaufmann, R.L.; Dusenbery, P.B.; Thomas, B.J.; Arnoldy, R.L.

    1978-01-01

    The electron velocity distribution function is presented in the energy range 25 eV 8 cm/s (E=300 eV) are nearly isotropic in pitch angle throughout the flight. Upgoing electrons show almost no pitch angle dependence beyond 120 0 , and their fluxes decline smoothly as energy increases, with little or no evidence of a plateau. Preliminary results of numerical integrations, to study bulk properties and stability of the plasma are presented

  6. Vestibular function testing.

    LENUS (Irish Health Repository)

    Lang, E E

    2010-06-01

    Vestibular symptoms of vertigo, dizziness and dysequilibrium are common complaints which can be disabling both physically and psychologically. Routine examination of the ear nose and throat and neurological system are often normal in these patients. An accurate history and thorough clinical examination can provide a diagnosis in the majority of patients. However, in a subgroup of patients, vestibular function testing may be invaluable in arriving at a correct diagnosis and ultimately in the optimal treatment of these patients.

  7. Analyzing Pseudophosphatase Function.

    Science.gov (United States)

    Hinton, Shantá D

    2016-01-01

    Pseudophosphatases regulate signal transduction cascades, but their mechanisms of action remain enigmatic. Reflecting this mystery, the prototypical pseudophosphatase STYX (phospho-serine-threonine/tyrosine-binding protein) was named with allusion to the river of the dead in Greek mythology to emphasize that these molecules are "dead" phosphatases. Although proteins with STYX domains do not catalyze dephosphorylation, this in no way precludes their having other functions as integral elements of signaling networks. Thus, understanding their roles in signaling pathways may mark them as potential novel drug targets. This chapter outlines common strategies used to characterize the functions of pseudophosphatases, using as an example MK-STYX [mitogen-activated protein kinase (MAPK) phospho-serine-threonine/tyrosine binding], which has been linked to tumorigenesis, apoptosis, and neuronal differentiation. We start with the importance of "restoring" (when possible) phosphatase activity in a pseudophosphatase so that the active mutant may be used as a comparison control throughout immunoprecipitation and mass spectrometry analyses. To this end, we provide protocols for site-directed mutagenesis, mammalian cell transfection, co-immunoprecipitation, phosphatase activity assays, and immunoblotting that we have used to investigate MK-STYX and the active mutant MK-STYXactive. We also highlight the importance of utilizing RNA interference (RNAi) "knockdown" technology to determine a cellular phenotype in various cell lines. Therefore, we outline our protocols for introducing short hairpin RNA (shRNA) expression plasmids into mammalians cells and quantifying knockdown of gene expression with real-time quantitative PCR (qPCR). A combination of cellular, molecular, biochemical, and proteomic techniques has served as powerful tools in identifying novel functions of the pseudophosphatase MK-STYX. Likewise, the information provided here should be a helpful guide to elucidating the

  8. Cybernetic functioning in stuttering

    Directory of Open Access Journals (Sweden)

    Ursula Zsilavecz

    1981-11-01

    Full Text Available The aim of this study was to evaluate different kinds of masking noise and DAF, in order to identify the condition which would elicit the highest incidence of fluency in a group of stutterers. The study demonstrates that masking noise and DAF can be effectively applied as an aid in a therapy programme, viz. noise can effectively be put to use so as to encourage and reinforce somesthesia. Stuttering is viewed as defective functioning in the cybernetic system.

  9. Function integrated track system

    OpenAIRE

    Hohnecker, Eberhard

    2010-01-01

    The paper discusses a function integrated track system that focuses on the reduction of acoustic emissions from railway lines. It is shown that the combination of an embedded rail system (ERS), a sound absorbing track surface, and an integrated mini sound barrier has significant acoustic advantages compared to a standard ballast superstructure. The acoustic advantages of an embedded rail system are particularly pronounced in the case of railway bridges. Finally, it is shown that a...

  10. On hereditarily rational functions

    OpenAIRE

    Nowak, Krzysztof Jan

    2012-01-01

    In this paper, we give a short proof of a theorem by Koll\\'{a}r on hereditarily rational functions. This is an answer to his appeal to find an elementary proof which does not rely so much on resolution of singularities. Our approach does not make use of desingularization techniques. Instead, we apply a stronger version of the \\L{}ojasiewicz inequality. Moreover, this allows us to sharpen Koll\\'{a}r's theorem.

  11. Generalised twisted partition functions

    CERN Document Server

    Petkova, V B

    2001-01-01

    We consider the set of partition functions that result from the insertion of twist operators compatible with conformal invariance in a given 2D Conformal Field Theory (CFT). A consistency equation, which gives a classification of twists, is written and solved in particular cases. This generalises old results on twisted torus boundary conditions, gives a physical interpretation of Ocneanu's algebraic construction, and might offer a new route to the study of properties of CFT.

  12. Network Function Virtualisation

    OpenAIRE

    Aakarshan Singh; Kamal Grover; Palak Bansal; Taranveer Singh Seekhon

    2017-01-01

    This paper is written to give basic knowledge of Network function virtualisation in network system. In this paper the work on NFV done till now has been collaborated. It describes how the challenges faced by industry lead to NFV and what is meaning of NFV and NFV architecture model. It also explains NFV Infrastructure is managed and the forwarding path on which packets traverse in NFV. A relationship of NFV with SDN and current research ongoing on NFV policies is discussed.

  13. Dynamics of cholinergic function

    International Nuclear Information System (INIS)

    Hanin, I.

    1986-01-01

    This book presents information on the following topics; cholinergic pathways - anatomy of the central nervous system; aging, DSAT and other clinical conditions; cholinergic pre- and post-synaptic receptors; acetylcholine release; cholinesterases, anticholinesterases and reactivators; acetylcholine synthesis, metabolism and precursors; second messenger messenger mechanisms; interaction of acetylcholine with other neurotransmitter systems; cholinergic mechanisms in physiological function, including cardiovascular events; and neurotoxic agents and false transmitters

  14. Applied functional analysis

    CERN Document Server

    Oden, J Tinsley

    2010-01-01

    The textbook is designed to drive a crash course for beginning graduate students majoring in something besides mathematics, introducing mathematical foundations that lead to classical results in functional analysis. More specifically, Oden and Demkowicz want to prepare students to learn the variational theory of partial differential equations, distributions, and Sobolev spaces and numerical analysis with an emphasis on finite element methods. The 1996 first edition has been used in a rather intensive two-semester course. -Book News, June 2010

  15. Choice Probability Generating Functions

    DEFF Research Database (Denmark)

    Fosgerau, Mogens; McFadden, Daniel L; Bierlaire, Michel

    This paper considers discrete choice, with choice probabilities coming from maximization of preferences from a random utility field perturbed by additive location shifters (ARUM). Any ARUM can be characterized by a choice-probability generating function (CPGF) whose gradient gives the choice...... probabilities, and every CPGF is consistent with an ARUM. We relate CPGF to multivariate extreme value distributions, and review and extend methods for constructing CPGF for applications....

  16. [Endocrine function in obesity].

    Science.gov (United States)

    Álvarez-Castro, Paula; Sangiao-Alvarellos, Susana; Brandón-Sandá, Iria; Cordido, Fernando

    2011-10-01

    Obesity is associated to significant disturbances in endocrine function. Hyper insulinemia and insulin resistance are the best known changes in obesity, but their mechanisms and clinical significance are not clearly established. Adipose tissue is considered to be a hormone-secreting endocrine organ; and increased leptin secretion from the adipocyte, a satiety signal, is a well-established endocrine change in obesity. In obesity there is a decreased GH secretion. Impairment of somatotropic function in obesity is functional and may be reversed in certain circumstances. The pathophysiological mechanism responsible for low GH secretion in obesity is probably multifactorial. There are many data suggesting that a chronic state of somatostatin hypersecretion results in inhibition of GH release. Increased FFA levels, as well as a deficient ghrelin secretion, probably contribute to the impaired GH secretion. In women, abdominal obesity is associated to hyperandrogenism and low sex hormone-binding globulin levels. Obese men, particularly those with morbid obesity, have decreased testosterone and gonadotropin levels. Obesity is associated to an increased cortisol production rate, which is compensated for by a higher cortisol clearance, resulting in plasma free cortisol levels that do not change when body weight increases. Ghrelin is the only known circulating orexigenic factor, and has been found to be decreased in obese people. In obesity there is also a trend to increased TSH and free T3 levels. Copyright © 2011 SEEN. Published by Elsevier Espana. All rights reserved.

  17. Orexins and gastrointestinal functions.

    Science.gov (United States)

    Baccari, M C

    2010-03-01

    Orexin A (OXA) and orexin B (OXB) are recently discovered neuropeptides that appear to play a role in various distinct functions such as arousal and the sleep-wake cycle as well as on appetite and regulation of feeding and energy homeostasis. Orexins were first described as neuropeptides expressed by a specific population of neurons in the lateral hypothalamic area, a region classically implicated in feeding behaviour. Orexin neurons project to numerous brain regions, where orexin receptors have been shown to be widely distributed: both OXA and OXB act through two subtypes of receptors (OX1R and OX2R) that belong to the G protein-coupled superfamily of receptors. Growing evidence indicates that orexins act in the central nervous system also to regulate gastrointestinal functions: animal studies have indeed demonstrated that centrally-injected orexins or endogenously released orexins in the brain stimulates gastric secretion and influence gastrointestinal motility. The subsequent identification of orexins and their receptors in the enteric nervous system (including the myenteric and the submucosal plexuses) as well as in mucosa and smooth muscles has suggested that these neuropeptides may also play a local action. In this view, emerging studies indicate that orexins also exert region-specific contractile or relaxant effects on isolated gut preparations. The aim of the proposed review is to summarize both centrally- and peripherally-mediated actions of orexins on gastrointestinal functions and to discuss the related physiological role on the basis of the most recent findings.

  18. Lutein and Brain Function

    Directory of Open Access Journals (Sweden)

    John W. Erdman

    2015-10-01

    Full Text Available Lutein is one of the most prevalent carotenoids in nature and in the human diet. Together with zeaxanthin, it is highly concentrated as macular pigment in the foveal retina of primates, attenuating blue light exposure, providing protection from photo-oxidation and enhancing visual performance. Recently, interest in lutein has expanded beyond the retina to its possible contributions to brain development and function. Only primates accumulate lutein within the brain, but little is known about its distribution or physiological role. Our team has begun to utilize the rhesus macaque (Macaca mulatta model to study the uptake and bio-localization of lutein in the brain. Our overall goal has been to assess the association of lutein localization with brain function. In this review, we will first cover the evolution of the non-human primate model for lutein and brain studies, discuss prior association studies of lutein with retina and brain function, and review approaches that can be used to localize brain lutein. We also describe our approach to the biosynthesis of 13C-lutein, which will allow investigation of lutein flux, localization, metabolism and pharmacokinetics. Lastly, we describe potential future research opportunities.

  19. Reassessing Function Points

    Directory of Open Access Journals (Sweden)

    G.R. Finnie

    1997-05-01

    Full Text Available Accurate estimation of the size and development effort for software projects requires estimation models which can be used early enough in the development life cycle to be of practical value. Function Point Analysis (FPA has become possibly the most widely used estimation technique in practice. However the technique was developed in the data processing environment of the 1970's and, despite undergoing considerable reassessment and formalisation, still attracts criticism for the weighting scoring it employs and for the way in which the function point score is adapted for specific system characteristics. This paper reviews the validity of the weighting scheme and the value of adjusting for system characteristics by studying their effect in a sample of 299 software developments. In general the value adjustment scheme does not appear to cater for differences in productivity. The weighting scheme used to adjust system components in terms of being simple, average or complex also appears suspect and should be redesigned to provide a more realistic estimate of system functionality.

  20. Hexagonalization of correlation functions

    Energy Technology Data Exchange (ETDEWEB)

    Fleury, Thiago [Instituto de Física Teórica, UNESP - University Estadual Paulista,ICTP South American Institute for Fundamental Research,Rua Dr. Bento Teobaldo Ferraz 271, 01140-070, São Paulo, SP (Brazil); Komatsu, Shota [Perimeter Institute for Theoretical Physics,31 Caroline St N Waterloo, Ontario N2L 2Y5 (Canada)

    2017-01-30

    We propose a nonperturbative framework to study general correlation functions of single-trace operators in N=4 supersymmetric Yang-Mills theory at large N. The basic strategy is to decompose them into fundamental building blocks called the hexagon form factors, which were introduced earlier to study structure constants using integrability. The decomposition is akin to a triangulation of a Riemann surface, and we thus call it hexagonalization. We propose a set of rules to glue the hexagons together based on symmetry, which naturally incorporate the dependence on the conformal and the R-symmetry cross ratios. Our method is conceptually different from the conventional operator product expansion and automatically takes into account multi-trace operators exchanged in OPE channels. To illustrate the idea in simple set-ups, we compute four-point functions of BPS operators of arbitrary lengths and correlation functions of one Konishi operator and three short BPS operators, all at one loop. In all cases, the results are in perfect agreement with the perturbative data. We also suggest that our method can be a useful tool to study conformal integrals, and show it explicitly for the case of ladder integrals.

  1. Carbasugars: Synthesis and Functions

    Science.gov (United States)

    Kobayashi, Yoshiyuki

    It is well recognized that glycosidase inhibitors are not only tools to elucidate the mechanism of a living system manipulated by glycoconjugates but also potential clinical drugs and insecticides by inducing the failure of glycoconjugates to perform their function. In this chapter, the syntheses and functions of natural glycosidase inhibitors (cyclophelitol , allosamidine , and trehazoilin ), which possess highly oxygenated and functionalized cyclohexanes or cyclopentanes in their structures and are defined as carbasugars , and the structure and activity relationships (SAR) of their derivatives are described. Also, recently much attention has been focused on neuraminidase inhibitors as anti-influenza drugs since relenza , which was derived from sialic acid, and also, tamiflu , which is the artificial carbasugar designed as a transition state analogue in the hydrolysis pathway of substrates by neuraminidase, were launched in the market. Herein, the medicinal chemistry efforts to discover tamiflu and some efficient syntheses applicable to process chemistry are described. Finally, useful synthetic methodologies for carbasugar formation from sugars are also introduced in this chapter.

  2. [Functional hypothalamic amenorrhea].

    Science.gov (United States)

    Stárka, Luboslav; Dušková, Michaela

    2015-10-01

    Functional hypothalamic amenorrhea (FHA) besides pregnancy and syndrome of polycystic ovary is one of the most common causes of secondary amenorrhea. FHA results from the aberrations in pulsatile gonadotropin-releasing hormone (GnRH) secretion, which in turn causes impairment of the gonadotropins (follicle-stimulating hormone and luteinizing hormone). FHA is a form of the defence of organism in situations where life functions are more important than reproductive function. FHA is reversible; it can be normalized after ceasing the stress situation. There are three types of FHA: weight loss related, stress-related, and exercise-related amenorrhea. The final consequences are complex hormonal changes manifested by profound hypoestrogenism. Additionally, these patients present mild hypercortisolemia, low serum insulin levels, low insulin-like growth factor 1 (IGF-1) and low total triiodothyronine. Women health in this disorder is disturbed in several aspects including the skeletal system, cardiovascular system, and mental problems. Patients manifest a decrease in bone mass density, which is related to an increase in fracture risk. Therefore, osteopenia and osteoporosis are the main long-term complications of FHA. Cardiovascular complications include endothelial dysfunction and abnormal changes in the lipid profile. FHA patients present significantly higher depression and anxiety and also sexual problems compared to healthy subjects.

  3. Thyroid function and obesity.

    Science.gov (United States)

    Laurberg, Peter; Knudsen, Nils; Andersen, Stig; Carlé, Allan; Pedersen, Inge Bülow; Karmisholt, Jesper

    2012-10-01

    Important interaction exists between thyroid function, weight control, and obesity. Several mechanisms seem to be involved, and in studies of groups of people the pattern of thyroid function tests depends on the balance of obesity and underlying thyroid disease in the cohort studied. Obese people with a normal thyroid gland tend to have activation of the hypothalamic-pituitary-thyroid axis with higher serum TSH and thyroid hormones in serum. On the other hand, small differences in thyroid function are associated with up to 5 kg difference in body weight. The weight loss after therapy of overt hypothyroidism is caused by excretion of water bound in tissues (myxoedema). Many patients treated for hyperthyroidism experience a gain of more weight than they lost during the active phase of the disease. The mechanism for this excessive weight gain has not been fully elucidated. New studies on the relation between L-T3 therapy and weight control are discussed. The interaction between weight control and therapy of thyroid disease is important to many patients and it should be studied in more detail.

  4. [Chewing and cognitive function].

    Science.gov (United States)

    Hirano, Yoshiyuki; Onozuka, Minoru

    2014-01-01

    Chewing does not only crush food to aid swallowing and digestion; it also helps to relieve stress and regulate cognitive functions, including alertness and executive function. It is well known that chewing gum is used for sleepiness prevention during work, learning, and driving. In addition, it has been shown in the elderly that a decrease in the number of residual teeth is related to dementia onset. These findings suggest a link between chewing and maintaining memory and attention. Recently, many studies regarding the effects of chewing on memory and attention were conducted using functional magnetic resonance imaging (fMRI) and electroencephalography (EEG). When a working memory task was used, the middle frontal gyrus in the dorsolateral prefrontal cortex showed greater activation in addition to producing higher alertness after chewing. Furthermore, using an attentional network test, reaction time shortened, and the anterior cingulate cortex and left frontal gyrus were both activated for the executive network. From these results, it is suggested that chewing elevates alertness, consequently leading to improvements in cognitive performance. In this review, we introduce findings concerning the effects of chewing on cognitive performance, and discuss the neuronal mechanisms underlying these effects.

  5. Mitochondria and Endothelial Function

    Science.gov (United States)

    Kluge, Matthew A.; Fetterman, Jessica L.; Vita, Joseph A.

    2013-01-01

    In contrast to their role in other cell types with higher energy demands, mitochondria in endothelial cells primarily function in signaling cellular responses to environmental cues. This article provides an overview of key aspects of mitochondrial biology in endothelial cells, including subcellular location, biogenesis, dynamics, autophagy, ROS production and signaling, calcium homeostasis, regulated cell death, and heme biosynthesis. In each section, we introduce key concepts and then review studies showing the importance of that mechanism to endothelial control of vasomotor tone, angiogenesis, and inflammatory activation. We particularly highlight the small number of clinical and translational studies that have investigated each mechanism in human subjects. Finally, we review interventions that target different aspects of mitochondrial function and their effects on endothelial function. The ultimate goal of such research is the identification of new approaches for therapy. The reviewed studies make it clear that mitochondria are important in endothelial physiology and pathophysiology. A great deal of work will be needed, however, before mitochondria-directed therapies are available for the prevention and treatment of cardiovascular disease. PMID:23580773

  6. A functional RG equation for the c-function

    DEFF Research Database (Denmark)

    Codello, A.; D'Odorico, G.; Pagani, C.

    2014-01-01

    , local potential approximation and loop expansion. In each case we construct the relative approximate c-function and find it to be consistent with Zamolodchikov's c-theorem. Finally, we present a relation between the c-function and the (matter induced) beta function of Newton's constant, allowing us...... to use heat kernel techniques to compute the RG running of the c-function....

  7. Logarithmically completely monotonic functions involving the Generalized Gamma Function

    Directory of Open Access Journals (Sweden)

    Faton Merovci

    2010-12-01

    Full Text Available By a simple approach, two classes of functions involving generalization Euler's gamma function and originating from certain  problems of traffic flow are proved to be logarithmically  completely monotonic and a class of functions involving the psi function is showed to be completely monotonic.

  8. Logarithmically completely monotonic functions involving the Generalized Gamma Function

    OpenAIRE

    Faton Merovci; Valmir Krasniqi

    2010-01-01

    By a simple approach, two classes of functions involving generalization Euler's gamma function and originating from certain  problems of traffic flow are proved to be logarithmically  completely monotonic and a class of functions involving the psi function is showed to be completely monotonic.

  9. Recurrence coefficients for discrete orthonormal polynomials and the Painlevé equations

    International Nuclear Information System (INIS)

    Clarkson, Peter A

    2013-01-01

    We investigate semi-classical generalizations of the Charlier and Meixner polynomials, which are discrete orthogonal polynomials that satisfy three-term recurrence relations. It is shown that the coefficients in these recurrence relations can be expressed in terms of Wronskians of modified Bessel functions and confluent hypergeometric functions, respectively for the generalized Charlier and generalized Meixner polynomials. These Wronskians arise in the description of special function solutions of the third and fifth Painlevé equations. (paper)

  10. Strange functions in real analysis

    CERN Document Server

    Kharazishvili, AB

    2005-01-01

    Weierstrass and Blancmange nowhere differentiable functions, Lebesgue integrable functions with everywhere divergent Fourier series, and various nonintegrable Lebesgue measurable functions. While dubbed strange or "pathological," these functions are ubiquitous throughout mathematics and play an important role in analysis, not only as counterexamples of seemingly true and natural statements, but also to stimulate and inspire the further development of real analysis.Strange Functions in Real Analysis explores a number of important examples and constructions of pathological functions. After introducing the basic concepts, the author begins with Cantor and Peano-type functions, then moves to functions whose constructions require essentially noneffective methods. These include functions without the Baire property, functions associated with a Hamel basis of the real line, and Sierpinski-Zygmund functions that are discontinuous on each subset of the real line having the cardinality continuum. Finally, he considers e...

  11. [Functional pathophysiology of consciousness].

    Science.gov (United States)

    Jellinger, Kurt A

    2009-01-01

    Consciousness (Latin conscientia "moral conscience"), according to the English philosopher John Locke (1632-1704) [103], is the awareness of all that occurs in the mind of a person, whereas the American philosopher John Searle (2000) defined it as "inner qualitative, subjective states and processes of awareness". In modern science it is defined as a continuous state of full awareness of the Self and one's relationship to the external and internal environment, describing the degree of wakefulness in which an organism recognizes stimuli. This widely discussed biological term for complex neuronal processes that allow an individuum to recognize itself and its environment and to act accordingly, has been and still is the subject of much research in philosophy and natural/neuroscience. Its definition is often used for awareness and recognition, too. While the Egyptians in the papyrus Edwin Smith already recognized the brain as the seat of consciousness, René Descartes (1644 [36]) believed its special structure should be "a small gland in the middle", but the anatomical structures and physiological processes involved in consciousness were elucidated only in the middle of the 20th century. Neuronal substrates include several functional networks that are hierarchically organized and cooperate functionally. The lowest level is the mesencephalic formatio reticularis and its projections to the thalamus that were identified als ascending reticular system (ARAS) by the classical experiments of Moruzzi and Magoun, whereas later analyses of patients with impaired consciousness provided further insights. The mesencephalic ARAS as motor of the function of higher structures projects 1. via the reticular thalamus diffusely to the cortex, 2. via hypothalamus to the basal forebrain and limbic system, and 3. to the medial raphe of the brainstem and locus coeruleus and their diffuse cortical projections. The reticular system is stimulated directly and indirectly via numerous collaterals

  12. Microbial Functional Gene Diversity Predicts Groundwater Contamination and Ecosystem Functioning.

    Science.gov (United States)

    He, Zhili; Zhang, Ping; Wu, Linwei; Rocha, Andrea M; Tu, Qichao; Shi, Zhou; Wu, Bo; Qin, Yujia; Wang, Jianjun; Yan, Qingyun; Curtis, Daniel; Ning, Daliang; Van Nostrand, Joy D; Wu, Liyou; Yang, Yunfeng; Elias, Dwayne A; Watson, David B; Adams, Michael W W; Fields, Matthew W; Alm, Eric J; Hazen, Terry C; Adams, Paul D; Arkin, Adam P; Zhou, Jizhong

    2018-02-20

    Contamination from anthropogenic activities has significantly impacted Earth's biosphere. However, knowledge about how environmental contamination affects the biodiversity of groundwater microbiomes and ecosystem functioning remains very limited. Here, we used a comprehensive functional gene array to analyze groundwater microbiomes from 69 wells at the Oak Ridge Field Research Center (Oak Ridge, TN), representing a wide pH range and uranium, nitrate, and other contaminants. We hypothesized that the functional diversity of groundwater microbiomes would decrease as environmental contamination (e.g., uranium or nitrate) increased or at low or high pH, while some specific populations capable of utilizing or resistant to those contaminants would increase, and thus, such key microbial functional genes and/or populations could be used to predict groundwater contamination and ecosystem functioning. Our results indicated that functional richness/diversity decreased as uranium (but not nitrate) increased in groundwater. In addition, about 5.9% of specific key functional populations targeted by a comprehensive functional gene array (GeoChip 5) increased significantly ( P contamination and ecosystem functioning. This study indicates great potential for using microbial functional genes to predict environmental contamination and ecosystem functioning. IMPORTANCE Disentangling the relationships between biodiversity and ecosystem functioning is an important but poorly understood topic in ecology. Predicting ecosystem functioning on the basis of biodiversity is even more difficult, particularly with microbial biomarkers. As an exploratory effort, this study used key microbial functional genes as biomarkers to provide predictive understanding of environmental contamination and ecosystem functioning. The results indicated that the overall functional gene richness/diversity decreased as uranium increased in groundwater, while specific key microbial guilds increased significantly as

  13. Neurophysiology of functional imaging.

    Science.gov (United States)

    van Eijsden, Pieter; Hyder, Fahmeed; Rothman, Douglas L; Shulman, Robert G

    2009-05-01

    The successes of PET and fMRI in non-invasively localizing sensory functions had encouraged efforts to transform the subjective concepts of cognitive psychology into objective physical measures. The assumption was that mental functions could be decomposed into non-overlapping, context-independent modules that are operated on by separable areas of a computer-like brain. The failures of cognitive modularity and of a very localized phrenology are generally, but not universally, accepted; but in their place, and usually not distinguished from the original revolutionary hopes of clarification, experimental results are being interpreted in terms of rather flexible definitions of both cognitive concepts and the degree of localization. In an alternative approach, we have connected fMRI, (13)C MRS, and electrophysiology measurements of brain energy to connect with observable properties of mental life (i.e., awareness). We illustrate this approach with a sensory stimulation experiment; the degree of localization found in BOLD signals was related to the global energy of the brain which, when manipulated by anesthetics, affected the degree of awareness. The influence of brain energy upon functional imaging maps is changing the interpretations of neuroimaging experiments, from psychological concepts generating computer-like responses to empirical responses dominated by the high brain energy and signaling at rest. In our view "baseline" is an operational term, an adjective that defines a property of a state of the system before it is perturbed by a stimulus. Given the dependence of observable psychological properties upon the "baseline" energy, we believe that it is unnecessarily limiting to define a particular state as the baseline.

  14. Expansions for Coulomb wave functions

    NARCIS (Netherlands)

    Boersma, J.

    1969-01-01

    In this paper we derive a number of expansions for Whittaker functions, regular and irregular Coulomb wave functions. The main result consists of a new expansion for the irregular Coulomb wave functions of orders zero and one in terms of regular Coulomb wave functions. The latter expansions are

  15. Functional Foods for Women's Health.

    Science.gov (United States)

    Lindeman, Alice K.

    2002-01-01

    Describes functional foods for women's health (foods or food ingredients that provide health benefits beyond basic nutrition), explaining that both whole and modified foods can be included as functional foods. The paper discusses the history, regulation, and promotion of functional foods; consumer interest in functional foods; how to incorporate…

  16. A Primer on Functional Analysis

    Science.gov (United States)

    Yoman, Jerome

    2008-01-01

    This article presents principles and basic steps for practitioners to complete a functional analysis of client behavior. The emphasis is on application of functional analysis to adult mental health clients. The article includes a detailed flow chart containing all major functional diagnoses and behavioral interventions, with functional assessment…

  17. Semigroups of data normalization functions

    NARCIS (Netherlands)

    Warrens, Matthijs J.

    2016-01-01

    Variable centering and scaling are functions that are typically used in data normalization. Various properties of centering and scaling functions are presented. It is shown that if we use two centering functions (or scaling functions) successively, the result depends on the order in which the

  18. Minerals and rumen function

    International Nuclear Information System (INIS)

    Smith, R.H.

    1984-01-01

    The mechanisms are discussed of some clinical disorders, characteristic only of ruminants and related to the effects of abnormal mineral intake on rumen function. With particular attention to tropical conditions, consideration is given to: (a) the possible effects of phosphorus deficiency on rumen microbial activity; (b) the depression of rumen microbial synthesis in sulphur deficiency; (c) the inhibition of magnesium absorption from the forestomachs; and (d) the involvement of the rumen microorganisms in leading to copper and vitamin B 12 deficiencies as a result of low intakes of cobalt. (author)

  19. [Metabolic functions and sport].

    Science.gov (United States)

    Riviere, Daniel

    2004-01-01

    Current epidemiological studies emphasize the increased of metabolic diseases of the adults, such as obesity, type-2 diabetes and metabolic syndromes. Even more worrying is the rising prevalence of obesity in children. It is due more to sedentariness, caused more by inactivity (television, video, games, etc.) than by overeating. Many studies have shown that regular physical activities benefit various bodily functions including metabolism. After dealing with the major benefits of physical exercise on some adult metabolic disorders, we focus on the prime role played by physical activity in combating the public health problem of childhood obesity.

  20. The hash function BLAKE

    CERN Document Server

    Aumasson, Jean-Philippe; Phan, Raphael; Henzen, Luca

    2014-01-01

    This is a comprehensive description of the cryptographic hash function BLAKE, one of the five final contenders in the NIST SHA3 competition, and of BLAKE2, an improved version popular among developers. It describes how BLAKE was designed and why BLAKE2 was developed, and it offers guidelines on implementing and using BLAKE, with a focus on software implementation.   In the first two chapters, the authors offer a short introduction to cryptographic hashing, the SHA3 competition, and BLAKE. They review applications of cryptographic hashing, they describe some basic notions such as security de

  1. Functions and graphs

    CERN Document Server

    Gelfand, I M; Shnol, E E

    1969-01-01

    The second in a series of systematic studies by a celebrated mathematician I. M. Gelfand and colleagues, this volume presents students with a well-illustrated sequence of problems and exercises designed to illuminate the properties of functions and graphs. Since readers do not have the benefit of a blackboard on which a teacher constructs a graph, the authors abandoned the customary use of diagrams in which only the final form of the graph appears; instead, the book's margins feature step-by-step diagrams for the complete construction of each graph. The first part of the book employs simple fu

  2. [Biotechnological functional systems].

    Science.gov (United States)

    Bokser, O Ia

    1999-01-01

    Based on the theory of functional systems and a concept of the quantum system of behavior, studies of the quantumsystems were conducted. Their structure, the interaction of biological and technical sections were analyzed. Mathematical, biophysical, and experimental models were designed. The paper shows that biotechnical quantumsystems are involved in the formation of biological feedback. A system with imperative feedback from the programmed and introduced current results of efforts has been developed and put into practice for the self-regulation of muscle tension. Training by using this biological feedback system causes a stable increase in the perception rate of proprioceptive stimulus in examinees (operates, sportsmen, neurological patients).

  3. Notes on functional analysis

    CERN Document Server

    Bhatia, Rajendra

    2009-01-01

    These notes are a record of a one semester course on Functional Analysis given by the author to second year Master of Statistics students at the Indian Statistical Institute, New Delhi. Students taking this course have a strong background in real analysis, linear algebra, measure theory and probability, and the course proceeds rapidly from the definition of a normed linear space to the spectral theorem for bounded selfadjoint operators in a Hilbert space. The book is organised as twenty six lectures, each corresponding to a ninety minute class session. This may be helpful to teachers planning a course on this topic. Well prepared students can read it on their own.

  4. Choice probability generating functions

    DEFF Research Database (Denmark)

    Fosgerau, Mogens; McFadden, Daniel; Bierlaire, Michel

    2013-01-01

    This paper considers discrete choice, with choice probabilities coming from maximization of preferences from a random utility field perturbed by additive location shifters (ARUM). Any ARUM can be characterized by a choice-probability generating function (CPGF) whose gradient gives the choice...... probabilities, and every CPGF is consistent with an ARUM. We relate CPGF to multivariate extreme value distributions, and review and extend methods for constructing CPGF for applications. The choice probabilities of any ARUM may be approximated by a cross-nested logit model. The results for ARUM are extended...

  5. Matrix string partition function

    CERN Document Server

    Kostov, Ivan K; Kostov, Ivan K.; Vanhove, Pierre

    1998-01-01

    We evaluate quasiclassically the Ramond partition function of Euclidean D=10 U(N) super Yang-Mills theory reduced to a two-dimensional torus. The result can be interpreted in terms of free strings wrapping the space-time torus, as expected from the point of view of Matrix string theory. We demonstrate that, when extrapolated to the ultraviolet limit (small area of the torus), the quasiclassical expressions reproduce exactly the recently obtained expression for the partition of the completely reduced SYM theory, including the overall numerical factor. This is an evidence that our quasiclassical calculation might be exact.

  6. Ramanujan's mock theta functions.

    Science.gov (United States)

    Griffin, Michael; Ono, Ken; Rolen, Larry

    2013-04-09

    In his famous deathbed letter, Ramanujan introduced the notion of a mock theta function, and he offered some alleged examples. Recent work by Zwegers [Zwegers S (2001) Contemp Math 291:268-277 and Zwegers S (2002) PhD thesis (Univ of Utrecht, Utrecht, The Netherlands)] has elucidated the theory encompassing these examples. They are holomorphic parts of special harmonic weak Maass forms. Despite this understanding, little attention has been given to Ramanujan's original definition. Here, we prove that Ramanujan's examples do indeed satisfy his original definition.

  7. Plasmodesmata: Structure and Function

    Directory of Open Access Journals (Sweden)

    Thomas David Geydan

    2006-07-01

    Full Text Available Plasmodesmata are channels that transverse the cell wall and membrane. These specialized and non passive channels act like gates that facilitate and regulate both communication and transportation of molecules such as water, nutrients, metabolites and macromolecules between plant cells. In the last decade a new point of view of plasmodesmata has emerged, and studies have  demonstrated that these channels are more complex. In this brief note, we pretend to expose the actual knowledge of plasmodesmata, focusing on their structure and function.

  8. Wigner Functions on a Lattice

    OpenAIRE

    Takami, A.; Hashimoto, T.; Horibe, M.; Hayashi, A.

    2000-01-01

    The Wigner functions on the one dimensional lattice are studied. Contrary to the previous claim in literature, Wigner functions exist on the lattice with any number of sites, whether it is even or odd. There are infinitely many solutions satisfying the conditions which reasonable Wigner functions should respect. After presenting a heuristic method to obtain Wigner functions, we give the general form of the solutions. Quantum mechanical expectation values in terms of Wigner functions are also ...

  9. Functionalism and consciousness.

    Science.gov (United States)

    Shoemaker, S

    1993-01-01

    It is widely held that a mental state and the subject's introspective belief about it are always 'distinct existences' and only contingently connected. This suggests that for each sort of mental state there could be a creature that is introspectively 'blind' with respect to states of that sort, meaning that while it is capable of having such states, and of conceiving of itself as having them, it is totally without introspective access to its states of that sort. It is argued here that introspective blindness with respect to many sorts of mental states, in particular beliefs and sensory states, is not a possibility, because it is incompatible with requirements of rationality that are internal to the functional roles that are constitutive of these states. Introspective accessibility is essential to the functional roles of such mental states when the conceptual and cognitive resources of the subject of those states are sufficiently rich to make beliefs and thoughts about them a possibility. This is a version of the view that such states are necessarily self-intimating and is incompatible with the perceptual model of introspection favoured by some functionalists as well as by many non-functionalists.

  10. Pleural function and lymphatics.

    Science.gov (United States)

    Negrini, D; Moriondo, A

    2013-02-01

    The pleural space plays an important role in respiratory function as the negative intrapleural pressure regimen ensures lung expansion and in the mean time maintains the tight mechanical coupling between the lung and the chest wall. The efficiency of the lung-chest wall coupling depends upon pleural liquid volume, which in turn reflects the balance between the filtration of fluid into and its egress out of the cavity. While filtration occurs through a single mechanism passively driving fluid from the interstitium of the parietal pleura into the cavity, several mechanisms may co-operate to remove pleural fluid. Among these, the pleural lymphatic system emerges as the most important one in quantitative terms and the only one able to cope with variable pleural fluid volume and drainage requirements. In this review, we present a detailed account of the actual knowledge on: (a) the complex morphology of the pleural lymphatic system, (b) the mechanism supporting pleural lymph formation and propulsion, (c) the dependence of pleural lymphatic function upon local tissue mechanics and (d) the effect of lymphatic inefficiency in the development of clinically severe pleural and, more in general, respiratory pathologies. © 2012 The Authors Acta Physiologica © 2012 Scandinavian Physiological Society.

  11. Mast Cell Function

    Science.gov (United States)

    da Silva, Elaine Zayas Marcelino; Jamur, Maria Célia

    2014-01-01

    Since first described by Paul Ehrlich in 1878, mast cells have been mostly viewed as effectors of allergy. It has been only in the past two decades that mast cells have gained recognition for their involvement in other physiological and pathological processes. Mast cells have a widespread distribution and are found predominantly at the interface between the host and the external environment. Mast cell maturation, phenotype and function are a direct consequence of the local microenvironment and have a marked influence on their ability to specifically recognize and respond to various stimuli through the release of an array of biologically active mediators. These features enable mast cells to act as both first responders in harmful situations as well as to respond to changes in their environment by communicating with a variety of other cells implicated in physiological and immunological responses. Therefore, the critical role of mast cells in both innate and adaptive immunity, including immune tolerance, has gained increased prominence. Conversely, mast cell dysfunction has pointed to these cells as the main offenders in several chronic allergic/inflammatory disorders, cancer and autoimmune diseases. This review summarizes the current knowledge of mast cell function in both normal and pathological conditions with regards to their regulation, phenotype and role. PMID:25062998

  12. Amusia and musical functioning.

    Science.gov (United States)

    Alossa, Nicoletta; Castelli, Lorys

    2009-01-01

    Music, as language, is a universal and specific trait to humans; it is a complex ability with characteristics that are unique compared to other cognitive abilities. Nevertheless, several issues are still open to debate, such as, for example, whether music is a faculty that is independent from the rest of the cognitive system, and whether musical skills are mediated by a single mechanism or by a combination of processes that are independent from one another. Moreover, the anatomical correlations of music have yet to be clarified. The goal of this review is to illustrate the current condition of the neuropsychology of music and to describe different approaches to the study of the musical functions. Hereby, we will describe the neuropsychological findings, suggesting that music is a special function carried out by different and dedicated processes that are probably subserved by different anatomical regions of the brain. Moreover, we will review the evidence obtained by working with brain-damaged patients suffering from music agnosia, a selective impairment in music recognition. Copyright 2009 S. Karger AG, Basel.

  13. Varicocele and testicular function

    Directory of Open Access Journals (Sweden)

    Alexander W Pastuszak

    2015-01-01

    Full Text Available Testicular varicocele, a dilation of the veins of the pampiniform plexus thought to increase testicular temperature via venous congestion, is commonly associated with male infertility. Significant study has clarified the negative impact of varicocele on semen parameters and more recent work has shed light on its detrimental effects on the molecular and ultrastructural features of sperm and the testicular microenvironment, as well as more clearly defined the positive impacts of treatment on couples′ fertility. The relationship between varicocele and testicular endocrine function, while known for some time based on histologic evaluation, has become more apparent in the clinical setting with a growing link between varicocele and hypogonadism. Finally, in the pediatric setting, while future study will clarify the impact of varicocele on fertility and testicular function, recent work supports a parallel effect of varicocele in adolescents and adults, suggesting a re-evaluation of current treatment approaches in light of the progressive nature of the condition and potential increased risk of future disease.

  14. ESD - FUNCTIONAL CLOTHING

    Directory of Open Access Journals (Sweden)

    SCARLAT Razvan

    2016-05-01

    Full Text Available The functional clothing represents a sustainable development direction of in the field of technical textiles, a bridge between various activity domains, a solution to user’s complex requirements. The research and development potential in the field is supported by the new fibers/ yarns generation, the new technologies and the market niches, as well. Protective clothing is now a major part of textile classified under technical textile. Protective clothing refers to the garment and other fabric related items designed to protect the wearer from harsh environmental effects that results in injuries or death. The innovation, as a result of convergence processing technologies, consumer demands and what is viable on the market, defines the personal protective equipment field. In this article, we present the work of an ESD protective clothing development. Therefore, it has been applied a modern knitting technology, on 7E and 12E STOLL machines, using cotton and wool yarns as base yarn and conductive yarns for plaiting structures. Also, the optimal parameters establishment and the functional requirements are aspects of the research activity performed. The experimental models have been conducted in order to demonstrate the design concept used and choosing the optimal variant. The characterization of the developed experimental variants took into account the evaluation of physico-mechanical and electrical characteristics. From the electrical point of view, the variants have been mainly evaluated through “point to point” method in terms of electrical isolation efficiency dimensional changes analysis.

  15. Expansion of continuum functions on resonance wave functions and amplitudes

    International Nuclear Information System (INIS)

    Bang, J.; Gareev, F.A.; Gizzatkulov, M.H.; Goncharov, S.A.

    1978-01-01

    To overcome difficulties encountered with wave functions of continuum spectrum (for example, in a shell model with continuum) the pole expansion (by the Mittag-Leffler theorem) of wave functions, scattering amplitudes and the Green functions with positive energies are considered. It is shown that resonance functions (the Gamov functions) form a complete set over which the continuum functions could be expanded. The general view of these expansions for final potentials and for the Coulomb repulsion potential are obtained and discussed. It is shown that the application of the method to nuclear structure calculations leads to simple algebraic equations

  16. Coupling coefficients for tensor product representations of quantum SU(2)

    International Nuclear Information System (INIS)

    Groenevelt, Wolter

    2014-01-01

    We study tensor products of infinite dimensional irreducible * -representations (not corepresentations) of the SU(2) quantum group. We obtain (generalized) eigenvectors of certain self-adjoint elements using spectral analysis of Jacobi operators associated to well-known q-hypergeometric orthogonal polynomials. We also compute coupling coefficients between different eigenvectors corresponding to the same eigenvalue. Since the continuous spectrum has multiplicity two, the corresponding coupling coefficients can be considered as 2 × 2-matrix-valued orthogonal functions. We compute explicitly the matrix elements of these functions. The coupling coefficients can be considered as q-analogs of Bessel functions. As a results we obtain several q-integral identities involving q-hypergeometric orthogonal polynomials and q-Bessel-type functions

  17. Coupling coefficients for tensor product representations of quantum SU(2)

    Science.gov (United States)

    Groenevelt, Wolter

    2014-10-01

    We study tensor products of infinite dimensional irreducible *-representations (not corepresentations) of the SU(2) quantum group. We obtain (generalized) eigenvectors of certain self-adjoint elements using spectral analysis of Jacobi operators associated to well-known q-hypergeometric orthogonal polynomials. We also compute coupling coefficients between different eigenvectors corresponding to the same eigenvalue. Since the continuous spectrum has multiplicity two, the corresponding coupling coefficients can be considered as 2 × 2-matrix-valued orthogonal functions. We compute explicitly the matrix elements of these functions. The coupling coefficients can be considered as q-analogs of Bessel functions. As a results we obtain several q-integral identities involving q-hypergeometric orthogonal polynomials and q-Bessel-type functions.

  18. What is a Sorting Function?

    DEFF Research Database (Denmark)

    Henglein, Fritz

    2009-01-01

    What is a sorting function—not a sorting function for a given ordering relation, but a sorting function with nothing given? Formulating four basic properties of sorting algorithms as defining requirements, we arrive at intrinsic notions of sorting and stable sorting: A function is a sorting...... are derivable without compromising data abstraction. Finally we point out that stable sorting functions as default representations of ordering relations have the advantage of permitting linear-time sorting algorithms; inequality tests forfeit this possibility....... function if and only it is an intrinsically parametric permutation function. It is a stable sorting function if and only if it is an intrinsically stable permutation function. We show that ordering relations can be represented isomorphically as inequality tests, comparators and stable sorting functions...

  19. Nostalgia: content, triggers, functions.

    Science.gov (United States)

    Wildschut, Tim; Sedikides, Constantine; Arndt, Jamie; Routledge, Clay

    2006-11-01

    Seven methodologically diverse studies addressed 3 fundamental questions about nostalgia. Studies 1 and 2 examined the content of nostalgic experiences. Descriptions of nostalgic experiences typically featured the self as a protagonist in interactions with close others (e.g., friends) or in momentous events (e.g., weddings). Also, the descriptions contained more expressions of positive than negative affect and often depicted the redemption of negative life scenes by subsequent triumphs. Studies 3 and 4 examined triggers of nostalgia and revealed that nostalgia occurs in response to negative mood and the discrete affective state of loneliness. Studies 5, 6, and 7 investigated the functional utility of nostalgia and established that nostalgia bolsters social bonds, increases positive self-regard, and generates positive affect. These findings demarcate key landmarks in the hitherto uncharted research domain of nostalgia.

  20. Baryons with functional methods

    International Nuclear Information System (INIS)

    Fischer, Christian S.

    2017-01-01

    We summarise recent results on the spectrum of ground-state and excited baryons and their form factors in the framework of functional methods. As an improvement upon similar approaches we explicitly take into account the underlying momentum-dependent dynamics of the quark-gluon interaction that leads to dynamical chiral symmetry breaking. For light octet and decuplet baryons we find a spectrum in very good agreement with experiment, including the level ordering between the positive- and negative-parity nucleon states. Comparing the three-body framework with the quark-diquark approximation, we do not find significant differences in the spectrum for those states that have been calculated in both frameworks. This situation is different in the electromagnetic form factor of the Δ, which may serve to distinguish both pictures by comparison with experiment and lattice QCD.

  1. Treatment of Functional Constipation

    Directory of Open Access Journals (Sweden)

    H Karami

    2014-04-01

    Full Text Available Childhood constipation is ofton a long_term problem requiring treatment over months or years. There is no single treatment metod for constipation and many children do not respond and continue to have chronic problems. Treatment is consisted of: Disimpaction,Drug adminstration , Diet modilation, and behaverial therapy. It is necessary in all cases that not responding to conventional therapy, un diagnosed organic causes, non proper drug, short course therapy, behaverial disorder and withholding should be considered. Internal anal achalasia, Neural tube defect, Neurointestinal dysplasia. and food allergy are the most important predisposing factors in treatment failer . PEG is drug of choice for treatment and therapy must be continued for several months or years. Psycologic consulting should be considered in patients with severe behaverial disorder.   Key words: Children, Functional Constipation, Treatment.

  2. Teaching Function at University

    Directory of Open Access Journals (Sweden)

    Alma Elena Figueroa Rubalcava

    2008-08-01

    Full Text Available A peremptory change in education and the higher education at universities is occurriyng. Since 60´s to date theoretical issues on the role of education are continuously on modification more rapidly than the teaching and learning practices that need more time to be realized. In this paper is presented a broad scope of main national and international organizations that propose, promote and systematize those educational changes since a half century ago and specially, those that impact the formation tendency based on competences. On other side, and not pretending be exhaustive, in this paper is highlighted a list of educational competences that teachers need to develop if they pretend to realize their teaching functions with high quality standards, mainly those related with velocity involvement as curriculum constructor.

  3. Functional memory metals

    International Nuclear Information System (INIS)

    Dunne, D.P.

    2000-01-01

    The field of shape memory phenomena in metals and alloys has developed in a sporadic fashion from a scientific curiosity to a vigorously growing niche industry, over a period close to a full working lifetime. Memory metal research and development is replete with scientist and engineer 'true believers', who can finally feel content that their longstanding confidence in the potential of these unusual functional materials has not been misplaced. This paper reviews the current range of medical and non-medical systems and devices which are based on memory metals and attempts to predict trends in applications over the next decade. The market is dominated by Ni Ti alloys which have proved to exhibit the best and most reproducible properties for application in a wide range of medical and non-medical devices

  4. Theory of function spaces

    CERN Document Server

    Triebel, Hans

    1983-01-01

    The book deals with the two scales Bsp,q and Fsp,q of spaces of distributions, where -8functions, Fourier multipliers and interpolation assertions. These topics are treated in Chapter 2, which is the heart

  5. Integration a functional approach

    CERN Document Server

    Bichteler, Klaus

    1998-01-01

    This book covers Lebesgue integration and its generalizations from Daniell's point of view, modified by the use of seminorms. Integrating functions rather than measuring sets is posited as the main purpose of measure theory. From this point of view Lebesgue's integral can be had as a rather straightforward, even simplistic, extension of Riemann's integral; and its aims, definitions, and procedures can be motivated at an elementary level. The notion of measurability, for example, is suggested by Littlewood's observations rather than being conveyed authoritatively through definitions of (sigma)-algebras and good-cut-conditions, the latter of which are hard to justify and thus appear mysterious, even nettlesome, to the beginner. The approach taken provides the additional benefit of cutting the labor in half. The use of seminorms, ubiquitous in modern analysis, speeds things up even further. The book is intended for the reader who has some experience with proofs, a beginning graduate student for example. It might...

  6. Indicators and their functions

    DEFF Research Database (Denmark)

    Gudmundsson, Henrik; Joumard, Robert; Aschemann, Ralf

    2010-01-01

    indicators? How can several indicators be jointly considered? And how can indicators be used in planning and decision making? Firstly we provide definition of 'indicator of environmental sustainability in transport'. The functions, strengths and weaknesses of indicators as measurement tools, and as decision...... for indicators and assessments. As the decision making context influences the perceived and actual needs for indicators and methods, we also analysed the dimensions and context of decision making. We derived criteria and methods for the assessment and selection of indicators of environmental sustainability......This report is the final report of the action COST 356 'EST - Towards the definition of a measurable environmentally sustainable transport'. It tries to answer the following questions: How can environmental impacts of transport be measured? How can measurements be transformed into operational...

  7. Functionally Graded Materials Database

    Science.gov (United States)

    Kisara, Katsuto; Konno, Tomomi; Niino, Masayuki

    2008-02-01

    Functionally Graded Materials Database (hereinafter referred to as FGMs Database) was open to the society via Internet in October 2002, and since then it has been managed by the Japan Aerospace Exploration Agency (JAXA). As of October 2006, the database includes 1,703 research information entries with 2,429 researchers data, 509 institution data and so on. Reading materials such as "Applicability of FGMs Technology to Space Plane" and "FGMs Application to Space Solar Power System (SSPS)" were prepared in FY 2004 and 2005, respectively. The English version of "FGMs Application to Space Solar Power System (SSPS)" is now under preparation. This present paper explains the FGMs Database, describing the research information data, the sitemap and how to use it. From the access analysis, user access results and users' interests are discussed.

  8. Thyroid function study

    International Nuclear Information System (INIS)

    Rocha, A.F.G. da

    1976-01-01

    A short revision of thyroid physiology is done. The radioisotopes of common use in thyroid investigation and the choice of the most appropriated ones are discussed. A table showing radioisotopes frequently used in this study, with their main characteristics is presented. Among several isotopic assays in thyroid propaedeutics, those that refer to the function study, topographic studies and tests 'in vitro' are pointed out. Exploration methods 'in vivo' are treated, such as: thyroid uptake; urinary excretion; thyroid scintigraphy, with scintigraphic imagings; stimulation test by TSH; suppression test; pbi; clearance test with perchlorate; iodine deficiency test and thyroid study with technetium. 'In vitro' proofs like triiodothyronine (T 3 ) and thyroxine (T 4 ) assays, as well as free thyroxine index, are treated. At last, the therapeutics by Iodine 131 is commented and emphasis is given to its application on the treatment of hyperthyroidism and thyroid carcinoma [pt

  9. Physically Functional Materials

    DEFF Research Database (Denmark)

    2002-01-01

    acids or peptides having azobenzenes or other physicially functional groups, e.g., photoresponsive groups, as side chains. These compounds may be synthesized using solid phase peptide synthesis techniques. Materials, e.g., thin films, comprising such compounds may be used for optical storage...... of information (holographic data storage), nonlinear optics (NLO), as photoconductors, photonic band-gap materials, electrically conducting materials, electroluminescent materials, piezo-electric materials, pyroelectric materials, magnetic materials, ferromagnetic materials, ferroelectric materials......, photorefractive materials, or materials in which light-induced conformational changes can be produced. Optical anisotropy may reversibly be generated with polarized laser light whereby a hologram is formed. First order diffraction efficiencies of up to around 80% have been obtained....

  10. IAEA's dual function

    International Nuclear Information System (INIS)

    1967-01-01

    'A factor of paramount importance is the dual nature of atomic energy, which is reflected in the dual function of the Agency; not only to promote, but also to safeguard the peaceful uses of atomic energy'. In taking the above statement as a theme in his address to the 1474th Plenary Meeting of the United Nations General Assembly (22nd November), the Director General, Dr. Sigvard Eklund, went on to speak of a few of the many areas in which society was feeling the impact of atomic energy. During the discussion which followed his report on the Agency's work nearly all speakers referred to the importance of the safeguards system as well as to positive achievements in developing nuclear potential for peaceful purposes

  11. Cardiac function studies

    International Nuclear Information System (INIS)

    Horn, H.J.

    1986-01-01

    A total of 27 patients were subjected tointramyocardial sequential scintiscanning (first pass) using 99m-Tc human serum albumin. A refined method is described that is suitable to analyse clinically relevant parameters like blood volume, cardiac output, ejection fraction, stroke volume, enddiastolic and endsystolic volumes as well as pulmonal transition time and uses a complete camaracomputer system adapted to the requirements of a routine procedure. Unless there is special hardware available, the method does not yet appear mature enough to be put into general practice. Its importance recently appeared in a new light due to the advent of particularly shortlived isotopes. For the time being, however, ECG-triggered equilibrium studies are to be preferred for cardiac function tests. (TRV) [de

  12. Functional ionic liquids

    International Nuclear Information System (INIS)

    Baecker, Tobias

    2012-01-01

    In the thesis at hand, new functional ionic liquids were investigated. Main focus was attended to their structure property relations and the structural features leading to a decrease of the melting point. New compounds of the type 1-butyl-3-methylimidazolium tris(N,Ndialkyldithiocarbamato) uranylate with variously substituated dithiocarbamato ligands were synthesized and characterized. Ligands with asymmetrical substitution pattern proved to be most suitable for ionic liquid formation. The single-crystal X-ray structures revealed the interactions in the solid state. Here, the first spectroscopic investigation of the U-S bond in sulfur donated uranyl complexes, up to now only observed in single-crystal X-ray structures, is presented, and the participation of the uranium f-orbitals is shown by theoretical calculations. Electrochemical investigations showed the accessibility of the respective U V O 2 + compounds. As well, ionic liquids with [FeCl 4 ] - and [Cl 3 FeOFeCl 3 ] 2- as anion were synthesized. Both of these anions contain high-spin Fe(III) centres in distorted tetrahedral environment, but exhibit different magnetic behaviour. The tetrachloroferrates show the usual paramagnetism, the m-oxobis(trichloroferrate) exhibits unexpectedly strong antiferromagnetic coupling, as was observed by NMR experiments and susceptibility measurements. To investigate structure-property relations in functionalized ionic liquids, a set of protic, primary alkylammonium and aprotic, quarternary trimethylalkylammonium based ionic liquids was synthesized, and characterized. The length of the alkyl chain was systematically varied, and all compounds were synthesized with and without hydroxyl group, as well as formate and bis(triflyl)amide salts, aiming at getting insight into the influence of the different structure parts on the respective ionic liquid's properties.

  13. Pulmonary function in microgravity

    Science.gov (United States)

    Guy, H. J.; Prisk, G. K.; West, J. B.

    1992-01-01

    We report the successful collection of a large quantity of human resting pulmonary function data on the SLS-1 mission. Preliminary analysis suggests that cardiac stroke volumes are high on orbit, and that an adaptive reduction takes at least several days, and in fact may still be in progress after 9 days on orbit. It also suggests that pulmonary capillary blood volumes are high, and remain high on orbit, but that the pulmonary interstitium is not significantly impacted. The data further suggest that the known large gravitational gradients of lung function have only a modest influence on single breath tests such as the SBN washout. They account for only approximately 25% of the phase III slope of nitrogen, on vital capacity SBN washouts. These gradients are only a moderate source of the cardiogenic oscillations seen in argon (bolus gas) and nitrogen (resident gas), on such tests. They may have a greater role in generating the normal CO2 oscillations, as here the phase relationship to argon and nitrogen reverses in microgravity, at least at mid exhalation in those subjects studied to date. Microgravity may become a useful tool in establishing the nature of the non-gravitational mechanisms that can now be seen to play such a large part in the generation of intra-breath gradients and oscillations of expired gas concentration. Analysis of microgravity multibreath nitrogen washouts, single breath washouts from more physiological pre-inspiratory volumes, both using our existing SLS-1 data, and data from the upcoming D-2 and SLS-2 missions, should be very fruitful in this regard.(ABSTRACT TRUNCATED AT 250 WORDS).

  14. Tamoxifen and ovarian function.

    Directory of Open Access Journals (Sweden)

    Martine Berliere

    Full Text Available BACKGROUND: Some studies suggest that the clinical parameter "amenorrhea" is insufficient to define the menopausal status of women treated with chemotherapy or tamoxifen. In this study, we investigated and compared the ovarian function defined either by clinical or biological parameters in pre-menopausal breast cancer patients treated with tamoxifen administered as adjuvant therapy. MATERIALS AND METHODS: Between 1999 and 2003, 138 premenopausal patients consecutively treated for early breast cancer were included. Sixty-eight received tamoxifen in monotherapy as the only adjuvant systemic treatment (Group I and 70 were treated with tamoxifen after adjuvant chemotherapy (Group II. All patients had a confirmed premenopausal status based on clinical parameters and hormonal values at study entry. They were followed prospectively every 3 months for 3 years: menses data, physical examination and blood tests (LH, FSH, 17-beta-estradiol. Vaginal ultrasonography was carried out every 6 months. After 3 years, prospective evaluation was completed and monitoring of ovarian function was performed as usual in our institution (1x/year. All data were retrospectively evaluated in 2011. RESULTS: Three patients were excluded from the study in group I and 2 were excluded in group II. Patients were divided into 4 subgroups according to clinical data, i.e. menses patterns. These patterns were assessed by questionnaires. a: Regular menses (>10 cycles/year b: Oligomenorrhea (5 to 9 cycles/year c: Severe oligomenorrhea (1 to 4 cycles/year d: Complete amenorrhea Estrogen levels did not appear to have any impact on disease-free survival rates after 3 or 8 years. FSH values were also documented and analyzed. They exhibited the same profile as estradiol values. CONCLUSIONS: Amenorrhea is an insufficient parameter to define menopausal status in patients receiving tamoxifen. Low estradiol levels must be coupled with other biological parameters to characterize endocrine status

  15. Lyapunov functionals and stability of stochastic functional differential equations

    CERN Document Server

    Shaikhet, Leonid

    2013-01-01

    Stability conditions for functional differential equations can be obtained using Lyapunov functionals. Lyapunov Functionals and Stability of Stochastic Functional Differential Equations describes the general method of construction of Lyapunov functionals to investigate the stability of differential equations with delays. This work continues and complements the author’s previous book Lyapunov Functionals and Stability of Stochastic Difference Equations, where this method is described for discrete- and continuous-time difference equations. The text begins with a description of the peculiarities of deterministic and stochastic functional differential equations. There follow basic definitions for stability theory of stochastic hereditary systems, and a formal procedure of Lyapunov functionals construction is presented. Stability investigation is conducted for stochastic linear and nonlinear differential equations with constant and distributed delays. The proposed method is used for stability investigation of di...

  16. The undefined function differs from the pointwise undefined function

    OpenAIRE

    Dosch, Walter (Prof.)

    1993-01-01

    The undefined function differs from the pointwise undefined function. - In: Joint Conference on Declarative Programming : Proceedings / Maria I. Sessa ... (eds.). - Salerno : Univ. degli Studi, 1995. - S. 257-268

  17. Functional asynchronous networks: Factorization of dynamics and function

    Directory of Open Access Journals (Sweden)

    Bick Christian

    2016-01-01

    Full Text Available In this note we describe the theory of functional asynchronous networks and one of the main results, the Modularization of Dynamics Theorem, which for a large class of functional asynchronous networks gives a factorization of dynamics in terms of constituent subnetworks. For these networks we can give a complete description of the network function in terms of the function of the events comprising the network and thereby answer a question originally raised by Alon in the context of biological networks.

  18. Functional equations and Green's functions for augmented scalar fields

    International Nuclear Information System (INIS)

    Klauder, J.R.

    1977-01-01

    Certain noncanonical self-coupled scalar quantum field theories, previously formulated by means of functional integration, are herein recast into the form of functional differential equations for the Green's functional. From these expressions the set of coupled equations relating the Green's functions is obtained. The new equations are compared with those of the conventional formulation, and are proposed as alternatives, especially for nonrenormalizable models when the conventional equations fail

  19. Robust loss functions for boosting.

    Science.gov (United States)

    Kanamori, Takafumi; Takenouchi, Takashi; Eguchi, Shinto; Murata, Noboru

    2007-08-01

    Boosting is known as a gradient descent algorithm over loss functions. It is often pointed out that the typical boosting algorithm, Adaboost, is highly affected by outliers. In this letter, loss functions for robust boosting are studied. Based on the concept of robust statistics, we propose a transformation of loss functions that makes boosting algorithms robust against extreme outliers. Next, the truncation of loss functions is applied to contamination models that describe the occurrence of mislabels near decision boundaries. Numerical experiments illustrate that the proposed loss functions derived from the contamination models are useful for handling highly noisy data in comparison with other loss functions.

  20. Extended asymptotic functions - some examples

    International Nuclear Information System (INIS)

    Todorov, T.D.

    1981-01-01

    Several examples of extended asymptotic functions of two variables are given. This type of asymptotic functions has been introduced as an extension of continuous ordinary functions. The presented examples are realizations of some Schwartz distributions delta(x), THETA(x), P(1/xsup(n)) and can be multiplied in the class of the asymptotic functions as opposed to the theory of Schwartz distributions. The examples illustrate the method of construction of extended asymptotic functions similar to the distributions. The set formed by the extended asymptotic functions is also considered. It is shown, that this set is not closed with respect to addition and multiplication