Qualitative analysis of Kantowski-Sachs metric in a generic class of f(R) models
Energy Technology Data Exchange (ETDEWEB)
Leon, Genly [Instituto de Física, Pontificia Universidad Católica de Valparaíso, Casilla 4950, Valparaíso (Chile); Roque, Armando A., E-mail: genly.leon@ucv.cl, E-mail: arestrada@ucf.edu.cu [Grupo de Estudios Avanzados, Universidad de Cienfuegos, Carretera a Rodas, Cuatro Caminos, s/n. Cienfuegos (Cuba)
2014-05-01
In this paper we investigate, from the dynamical systems perspective, the evolution of a Kantowski-Sachs metric in a generic class of f(R) models. We present conditions (i.e., differentiability conditions, existence of minima, monotony intervals, etc.) for a free input function related to the f(R), that guarantee the asymptotic stability of well-motivated physical solutions, specially, self-accelerated solutions, allowing to describe both inflationary- and late-time acceleration stages of the cosmic evolution. We discuss which f(R) theories allows for a cosmic evolution with an acceptable matter era, in correspondence to the modern cosmological paradigm. We find a very rich behavior, and amongst others the universe can result in isotropized solutions with observables in agreement with observations, such as de Sitter, quintessence-like, or phantom solutions. Additionally, we find that a cosmological bounce and turnaround are realized in a part of the parameter-space as a consequence of the metric choice.
Qualitative analysis of Kantowski-Sachs metric in a generic class of $f(R)$ models
Leon, Genly
2013-01-01
In this paper we investigate, from the dynamical systems perspective, the evolution of a Kantowski-Sachs metric in a generic class of $f(R)$ models. We present conditions (i. e., differentiability conditions, existence of minima, monotony intervals, etc.) for a free input function related to the $f(R)$, that guarantee the asymptotic stability of well-motivated physical solutions, specially, self-accelerated solutions, allowing to describe both inflationary- and late-time acceleration stages of the cosmic evolution. We discuss which $f(R)$ theories allows for a cosmic evolution with an acceptable matter era, in correspondence to the modern cosmological paradigm. We find a very rich behavior, and amongst others the universe can result in isotropized solutions with observables in agreement with observations, such as de Sitter, quintessence-like, or phantom solutions. Additionally, we find that a cosmological bounce and turnaround are realized in a part of the parameter-space as a consequence of the metric choice...
Perturbations of Kantowski-Sachs models
Bradley, Michael; Keresztes, Zoltán; Gergely, László Á; Dunsby, Peter K S
2013-01-01
Perturbations of Kantowski-Sachs models with a positive cosmological constant are considered in a harmonic decomposition, in the framework of gauge invariant 1+3 and 1+1+2 covariant splits of spacetime. Scalar, vector and tensor modes are allowed, however they remain vorticity-free and of perfect fluid type. The dynamics is encompassed in six evolution equations for six harmonic coefficients.
Noncanonical phase-space noncommutativity and the Kantowski-Sachs singularity for black holes
Bastos, Catarina; Bertolami, Orfeu; Dias, Nuno Costa; Prata, João Nuno
2011-07-01
We consider a cosmological model based upon a noncanonical noncommutative extension of the Heisenberg-Weyl algebra to address the thermodynamical stability and the singularity problem of black holes whose interior are described by the Kantowski-Sachs metric and modeled by a noncommutative extension of the Wheeler-DeWitt equation. We compute the temperature and entropy of these black holes and compare the results with the Hawking values. We observe that it is actually the noncommutativity in the momentum sector that allows for the existence of a minimum in the potential, which is the key to apply the Feynman-Hibbs procedure. It is shown that this noncommutative model generates a nonunitary dynamics that predicts a vanishing probability in the neighborhood of the singularity. This result effectively regularizes the Kantowski-Sachs singularity and generalizes a similar result, previously obtained for the case of Schwarzschild black holes.
Perturbations of Kantowski-Sachs models with a cosmological constant
Keresztes, Zoltán; Bradley, Michael; Dunsby, Peter K S; Gergely, László Á
2013-01-01
We investigate perturbations of Kantowski-Sachs models with a positive cosmological constant, using the gauge invariant 1+3 and 1+1+2 covariant splits of spacetime together with a harmonic decomposition. The perturbations are assumed to be vorticity-free and of perfect fluid type, but otherwise include general scalar, vector and tensor modes. In this case the set of equations can be reduced to six evolution equations for six harmonic coefficients.
Kantowski-Sachs Universes sourced by a Skyrme fluid
Parisi, Luca; Vilasi, Gaetano
2014-01-01
The Kantowski-Sachs cosmological model sourced by a Skyrme field and a cosmological constant is considered in the framework of General Relativity. Assuming a constant radial profile function for the hedgehog ansatz, the Skyrme contribution to Einstein equations is shown to be equivalent to an anisotropic fluid. Using dynamical system techniques, a qualitative analysis of the cosmological equations is presented. Physically interesting features of the model such as isotropization, bounce and recollapse are discussed.
Unitary evolution for a quantum Kantowski-Sachs cosmology
Pal, Sridip
2015-01-01
It is shown that like Bianchi I, V and IX models, a Kantowski-Sachs cosmological model also allows a unitary evolution on quantization. It has also been shown that this unitarity is not at the expense of the anisotropy. Non-unitarity, if there is any, cannot escape notice in this as the evolution is studied against a properly oriented time parameter fixed by the evolution of the fluid. Furthermore, we have constructed a wave-packet by superposing different energy eigenstates, thereby establishing unitarity in a non-trivial way, which is a stronger result than an energy eigenstate trivially giving time independent probability density. For $\\alpha\
No bounce behaviour in Kantowski-Sachs Cosmologies
Solomons, D M; Ellis, G; Solomons, Deon; Dunsby, Peter; Ellis, George
2001-01-01
Many cosmological scenarios envisage either a bounce of the universe at early times, or collapse of matter locally to form a black hole which re-expands into a new expanding universe region. Energy conditions preclude this happening for ordinary matter in general relativistic universes, but scalar or dilatonic fields can violate some of these conditions, and so could possibly provide bounce behaviour. In this paper we show that such bounces cannot occur in Kantowski-Sachs models without violating the {\\it reality condition} $\\dot{\\phi}^2\\geq 0$.
Non-Canonical Phase-Space Noncommutativity and the Kantowski-Sachs singularity for Black Holes
Bastos, Catarina; Dias, Nuno Costa; Prata, João Nuno
2010-01-01
We consider a cosmological model based upon a non-canonical noncommutative extension of the Heisenberg-Weyl algebra to address the thermodynamical stability and the singularity problem of both the Schwarzschild and the Kantowski-Sachs black holes. The interior of the black hole is modelled by a noncommutative extension of the Wheeler-DeWitt equation. We compute the temperature and entropy of a Kantowski-Sachs black hole and compare our results with the Hawking values. Again, the noncommutativity in the momenta sector allows us to have a minimum in the potential, which is relevant in order to apply the Feynman-Hibbs procedure. For Kantowski-Sachs black holes, the same model is shown to generate a non-unitary dynamics, predicting vanishing total probability in the neighborhood of the singularity. This result effectively regularizes the Kantowski-Sachs singularity and generalizes a similar result, previously obtained for the case of Schwarzschild black hole.
Bounce behaviour in Kantowski-Sachs and Bianchi cosmologies
Energy Technology Data Exchange (ETDEWEB)
Solomons, Deon [Cape Peninsula University of Technology, Cape Town (South Africa); Dunsby, Peter K S [Department of Mathematics and Applied Mathematics, University of Cape Town, Rondebosch 7701, Cape Town (South Africa); Ellis, George F R [Department of Mathematics and Applied Mathematics, University of Cape Town, Rondebosch 7701, Cape Town (South Africa)
2006-12-07
Many cosmological scenarios envisage either a bounce of the universe at early times, or collapse of matter locally to form a black hole which re-expands into a new expanding universe region. Energy conditions preclude this happening for ordinary matter in general relativistic universes, but scalar or dilatonic fields can violate some of these conditions, and so could possibly provide bounce behaviour. In this paper we show that such bounces cannot occur in Kantowski-Sachs models without violating the reality condition {phi}-dot{sup 2} {>=}0. This also holds true for other isotropic spatially homogeneous Bianchi models, with the exception of closed Friedmann-Robertson-Walker and Bianchi IX models; bounce behaviour violates the weak energy condition {rho} {>=} 0 and {rho} + p {>=} 0. We turn to the Randall-Sundrum type braneworld scenario for a possible resolution of this problem.
Kantowski-Sachs Einstein-aether perfect fluid models
Latta, Joey
2016-01-01
We investigate Kantowski-Sachs models in Einstein-aether theory with a perfect fluid source using dynamical system tools. We find an inflationary source at early times, and an inflationary sink at late times, for a wide region in the parameter space. The results by A. A. Coley, G. Leon, P. Sandin and J. Latta, JCAP {\\bf 12}, 010 (2015) are then re-obtained as particular cases. Additionally, we select other values for non-GR parameters which are consistent with current constraints, getting a very rich phenomenology. Particularly, we find solutions with infinite shearing, zero curvature, and infinity matter energy density in comparison with the Hubble scalar. We also have stiff-like future attractors, anisotropic late-time attractors, or both, in some special cases. Such results are developed analytically, and then verified by numerics. From the cosmological point of view, the more interesting fixed points are those representing accelerated solutions. However, the accelerated solutions do not isotropize, and th...
Kantowski-Sachs Einstein-æther perfect fluid models
Latta, Joey; Leon, Genly; Paliathanasis, Andronikos
2016-11-01
We investigate Kantowski-Sachs models in Einstein-æ ther theory with a perfect fluid source using the singularity analysis to prove the integrability of the field equations and dynamical system tools to study the evolution. We find an inflationary source at early times, and an inflationary sink at late times, for a wide region in the parameter space. The results by A.A. Coley, G. Leon, P. Sandin and J. Latta (JCAP 12 (2015) 010), are then re-obtained as particular cases. Additionally, we select other values for the non-GR parameters which are consistent with current constraints, getting a very rich phenomenology. In particular, we find solutions with infinite shear, zero curvature, and infinite matter energy density in comparison with the Hubble scalar. We also have stiff-like future attractors, anisotropic late-time attractors, or both, in some special cases. Such results are developed analytically, and then verified by numerics. Finally, the physical interpretation of the new critical points is discussed.
Kantowski-Sachs cosmological solutions in the generalized teleparallel gravity via Noether symmetry
Motavalli, H.; Akbarieh, A. Rezaei; Nasiry, M.
2016-04-01
We study the f(T) theory as an extension of teleparallel gravity and consider the Noether symmetry of Kantowski-Sachs (KS) anisotropic model for this theory. We specify the explicit teleparallel form of f(T) and find the corresponding exact cosmological solutions under the assumption that the Lagrangian admits the Noether symmetry. It is found that the universe experiences a power law expansion for the scale factors in the context of f(T) theory. By deriving equation of state (EOS) parameter, we show that the universe passes through the phantom and ΛCDM theoretical scenarios. In this way, we estimate a lower limit age for the universe in excellent agreement with the value reported from recent observations. When KS model reduces to the flat Friedmann-Robertson-Walker (FRW) metric, our results are properly transformed into the corresponding values.
Alvarenga, F G; Freitas, R C; Gonçalves, S V B
2015-01-01
In this paper we study the quantum Kantowski-Sachs model and we solve the Wheeler-DeWitt equation in minisuperspace to obtain the wave function of the corresponding universe. The perfect fluid is described by the Schutz's canonical formalism, which allows to attribute dynamical degrees of freedom to matter. The time is introduced phenomenologically using the fluid's degrees of freedom. In particular, we adopt a stiff matter fluid. The Kantowski-Sachs model is also presented with the introduction of so-called geometric time. Finally, the agreement between the results is analyzed and the possibility of equivalence between the two approaches is discussed.
Exact solution of the Einstein-Skyrme model in a Kantowski-Sachs spacetime
Paliathanasis, Andronikos; Tsamparlis, Michael
2017-04-01
We consider a Skyrme fluid with a constant radial profile in locally rotational Kantowski-Sachs spacetime. The Skyrme fluid is an anisotropic fluid with zero heat flux and with an equation of state parameter wS that |ws | ≤ 1/3. From the Einstein field equations we define the Wheeler-DeWitt equation. For the last equation we perform a Lie symmetry classification and we determine the invariant solutions for the wavefunction of the model. Moreover from the Lie symmetries of the Wheeler-DeWitt equation we construct Noetherian conservation laws for the field equations which we use in order to write the solution in closed form. We show that all of the cosmological parameters are expressed in terms of the scale factor of the two dimensional sphere of the Kantowski-Sachs spacetime. Finally from the application of Noether's theorem for the Wheeler-DeWitt equation we derive conservation laws for the wavefunction of the universe.
Bianchi type-I, type-III and Kantowski-Sachs solutions in f( T) gravity
Rodrigues, M. E.; Kpadonou, A. V.; Rahaman, F.; Oliveira, P. J.; Houndjo, M. J. S.
2015-06-01
In the context of modified tele-parallel theory of gravity, we undertake cosmological anisotropic models and search for their solutions. Within a suitable choice of non-diagonal tetrads, the decoupled equations of motion are obtained for Bianchi-I, Bianchi-III and Kantowski-Sachs models, from which we obtain the correspondent solutions. By the way, energy density and pressures are also obtained, showing, as an important result, that our universe may live a quintessence like universe even while anisotropic models are considered.
Saini, Sahil; Singh, Parampreet
2016-12-01
Resolution of singularities in the Kantowski-Sachs model due to non-perturbative quantum gravity effects is investigated. Using the effective spacetime description for the improved dynamics version of loop quantum Kantowski-Sachs spacetimes, we show that even though expansion and shear scalars are universally bounded, there can exist events where curvature invariants can diverge. However, such events can occur only for very exotic equations of state when pressure or derivatives of energy density with respect to triads become infinite at a finite energy density. In all other cases curvature invariants are proved to remain finite for any evolution in finite proper time. We find the novel result that all strong singularities are resolved for arbitrary matter. Weak singularities pertaining to above potential curvature divergence events can exist. The effective spacetime is found to be geodesically complete for particle and null geodesics in finite time evolution. Our results add to a growing evidence for generic resolution of strong singularities using effective dynamics in loop quantum cosmology by generalizing earlier results on isotropic and Bianchi-I spacetimes.
A note on proper affine symmetry in Kantowski-Sachs and Bianchi type III space-times
Shabbir, Ghulam
2016-01-01
We investigate proper affine symmetry for the Kantowski-Sachs and Bianchi type III space-times by using holonomy and decomposability, the rank of the 6X6 Riemann matrix and direct integration techniques. It is shown that the very special classes of the above space-times admit proper affine vector fields.
Shabbir, Ghulam
2011-01-01
A complete study of Kantowski-Sachs and Bianchi type III space-times according to their proper homothetic vector fields is given by using direct integration technique. Using the above mentioned technique we have shown that very special classes of the above space-times admit proper homothetic vector fields. The dimension of homothetic vector fields is five.
Kantowski-Sachs Universe in the Varying Speed of Light Theory
Khadekar, G S; Ray, Saibal
2016-01-01
In this work we consider the Kantowski-Sachs (KS) universe in the framework of varying speed of light theory. We present the general solutions of the gravitational field equations with variable speed of light $c(t)$, gravitational coupling parameter $G(t)$ and the decaying vacuum energy $\\Lambda(t)$ for the KS model. In the limiting case for the equation of state (EOS) parameter $\\gamma=2$ (stiff fluid with $p=\\rho c^2$) and $\\gamma =1$ (dust with $p=0$), exact solutions of the field equations are obtained. The numerical solutions are also presented for both the cases. Moreover, it is shown that in the limiting case of large time, the mean anisotropy parameter tends to zero for $\\gamma=2$ and $\\gamma=1$. Thus the time variation of the fundamental constants provides an effective mechanism for the isotropization of the KS universe.
Kantowski-Sachs Universe Models in $f(T)$ Theory of Gravity
Amir, M Jamil
2015-01-01
The $f(T)$ theory is recently proposed to explain the present cosmic accelerating expansion of the universe. $f(T)$ theory is an extension of Teleparallel theory of gravity, where $T$ is the torsion scalar. This paper contains the construction of $f(T)$ models within the Kantowski-Sachs universe. For this purpose, we use conservation equation and equation of state parameter, which represents the different phases of the universe. We discuss possible cases for the matter dominated era, radiation dominated era, present dark energy phase and their combinations. Particularly, a constant solution has been obtained which may correspond to the cosmological constant. Further, we consider two well known $f(T)$ models and derive the equation of state parameter and discuss the cosmic acceleration. Also, the Hubble parameter and average scale factor have been evaluated.
(Non) singular Kantowski-Sachs Universe from quantum spherically reduced matter
Nojiri, S; Odintsov, S D; Osetrin, K E
1999-01-01
Using s-wave and large $N$ approximation the one-loop effective action for 2d dilaton coupled scalars and spinors which are obtained by spherical reduction of 4d minimal matter is found. Quantum effective equations for reduced Einstein gravity are written. Their analytical solutions corresponding to 4d Kantowski-Sachs (KS) Universe are presented. For quantum-corrected Einstein gravity we get non-singular KS cosmology which represents 1) quantum-corrected KS cosmology which existed on classical level or 2)purely quantum solution which had no classical limit. The analogy with Nariai BH is briefly mentioned. For purely induced gravity (no Einstein term) we found general analytical solution but all KS cosmologies under discussion are singular. The corresponding equations of motion are reformulated as classical mechanics problem of motion of unit mass particle in some potential $V$.
Two-oscillator Kantowski-Sachs model of the Schwarzschild black hole interior
Djordjevic, Goran S.; Nesic, Ljubisa; Radovancevic, Darko
2016-08-01
In this paper the interior of the Schwarzschild black hole, which is presented as a vacuum, homogeneous and anisotropic Kantowski-Sachs minisuperspace cosmological model, is considered. Lagrangian of the model is reduced by a suitable coordinate transformation to Lagrangian of two decoupled oscillators with the same frequencies and with zero energy in total (an oscillator-ghost-oscillator system). The model is presented in a classical, a p-adic and a noncommutative case. Then, within the standard quantum approach Wheeler-DeWitt equation and its general solutions, i.e. a wave function of the model is written, and then an adelic wave function is constructed. Finally, thermodynamics of the model is studied by using the Feynman-Hibbs procedure.
Two-oscillator Kantowski-Sachs model of the Schwarzschild black hole interior
Djordjevic, Goran S; Radovancevic, Darko
2015-01-01
In this paper the interior of the Schwarzschild black hole, which is presented as a vacuum homogeneous and anisotropic Kantowski-Sachs minisuperspace cosmological model, is considered. Lagrangian of the model is reduced by a suitable coordinate transformation to Lagrangian of two decoupled oscillators with the same frequencies and with zero energy in total (an oscillator-ghost-oscillator system). The model will be presented in a classical, a p-adic and a noncommutative case. Then, within the standard quantum approach Wheeler-DeWitt equation and its general solutions, i.e. a wave function of the model, will be written, and then an adelic wave function will be constructed. Finally, thermodynamics of the model will be studied by using the Feynman-Hibbs procedure.
Camci, U; Oz, I Basaran
2016-01-01
The Noether symmetry approach is useful tool to restrict the arbitrariness in a gravity theory when the equations of motion are underdetermined due to the high number of functions to be determined in the ansatz. We consider two scalar-coupled theories of gravity, one motivated by induced gravity, the other more standard; in Bianchi I, Bianchi III and Kantowski-Sachs cosmological models. For these models, we present a full set of Noether gauge symmetries, which are more general than those obtained by the strict Noether symmetry approach in our recent work. Some exact solutions are derived using the first integrals corresponding to the obtained Noether gauge symmetries.
Jamal, Sameerah; Shabbir, Ghulam
2017-02-01
We study the geometric properties of generators for the Klein-Gordon equation in Kantowski-Sachs and certain Bianchi-type spaces. Several versions of the Klein-Gordon equation are derived from its dependence on a potential function. The criteria for different versions of the (1+3) Klein-Gordon equation originates from analyzing three sources, viz. through generators that are identically the Killing algebra, or with the Killing vector fields that are recast into linear combinations and thirdly, real sub-algebras within the conformal algebra. In turn, these equations admit a catalogue of infinitesimal symmetries that are equivalent to the corresponding Killing vector fields in Kantowski-Sachs, Bianchi type III, IX, VIII, VI0 and VII0 space-times, with the exception of a linear vector W=upartialu in every case. The sheer number of results are displayed in appropriate tables. Subsequently, in application, we derive some Noetherian conservation laws and identify some exact solutions by quadratures.
The Bondi-Sachs metric at the vertex of a null cone: axially symmetric vacuum solutions
Mädler, Thomas
2012-01-01
In the Bondi-Sachs formulation of General Relativity space-time is foliated via a family of null cones. If these null cones are defined such that their vertices are traced by a regular world-line then the metric tensor has to obey regularity conditions at the vertices. We explore these regularity conditions when the world line is a time-like geodesic. In particular, we solve the Einstein equations for the Bondi-Sachs metric near the vertices for axially symmetric vacuum space- times. The metric is calculated up to third order corrections with respect to a flat metric along the time-like geodesic, as this is the lowest order where non- linear coupling of the metric coefficients occurs. We also determine the boundary conditions of the metric to arbitrary order of these corrections when a linearized and axially symmetric vacuum space-time is assumed. In both cases we find that (i) the initial data on the null cone must have a very rigid angular structure for the vertex to be a regular point, and (ii) the initial...
Mädler, Thomas
2016-01-01
The Bondi-Sachs formalism of General Relativity is a metric-based treatment of the Einstein equations in which the coordinates are adapted to the null geodesics of the spacetime. It provided the first convincing evidence that gravitational radiation is a nonlinear effect of general relativity and that the emission of gravitational waves from an isolated system is accompanied by a mass loss from the system. The asymptotic behaviour of the Bondi-Sachs metric revealed the existence of the symmetry group at null infinity, the Bondi-Metzner-Sachs group, which turned out to be larger than the Poincare group.
Resources - Tay-Sachs ... The following organizations provide information on Tay-Sachs disease : US National Library of Medicine -- ghr.nlm.nih.gov/condition/tay-sachs-disease March of Dimes -- www.marchofdimes.com/pnhec/ ...
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Tay-Sachs and Sandhoff Diseases
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Genetics Home Reference: Tay-Sachs disease
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SAChES: Scalable Adaptive Chain-Ensemble Sampling.
Energy Technology Data Exchange (ETDEWEB)
Swiler, Laura Painton [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Ray, Jaideep [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Ebeida, Mohamed Salah [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Huang, Maoyi [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hou, Zhangshuan [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bao, Jie [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Ren, Huiying [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
2017-08-01
We present the development of a parallel Markov Chain Monte Carlo (MCMC) method called SAChES, Scalable Adaptive Chain-Ensemble Sampling. This capability is targed to Bayesian calibration of com- putationally expensive simulation models. SAChES involves a hybrid of two methods: Differential Evo- lution Monte Carlo followed by Adaptive Metropolis. Both methods involve parallel chains. Differential evolution allows one to explore high-dimensional parameter spaces using loosely coupled (i.e., largely asynchronous) chains. Loose coupling allows the use of large chain ensembles, with far more chains than the number of parameters to explore. This reduces per-chain sampling burden, enables high-dimensional inversions and the use of computationally expensive forward models. The large number of chains can also ameliorate the impact of silent-errors, which may affect only a few chains. The chain ensemble can also be sampled to provide an initial condition when an aberrant chain is re-spawned. Adaptive Metropolis takes the best points from the differential evolution and efficiently hones in on the poste- rior density. The multitude of chains in SAChES is leveraged to (1) enable efficient exploration of the parameter space; and (2) ensure robustness to silent errors which may be unavoidable in extreme-scale computational platforms of the future. This report outlines SAChES, describes four papers that are the result of the project, and discusses some additional results.
Ethical Issues with Genetic Testing for Tay-Sachs.
Clayton, Tricia
Several genetic disorders are specific to Jewish heritage; one of the most devastating is Tay-Sachs disease.Tay-Sachs is a fatal hereditary disease, causing progressive neurological problems for which there is no cure. Ethical issues surrounding genetic testing for Tay-Sachs within the Jewish community continue to be complex and multifaceted. A perspective of Tay-Sachs, using rights-based ethics and virtue ethics as a theoretical framework, is explored.
George Wilbur: Otto Rank and Hanns Sachs.
Roazen, Paul
2006-01-01
George Wilbur, a pioneering Cape Cod psychoanalytic psychiatrist, was a long-standing editor of the journal "American Imago," and an excellent source of information about the Viennese analysts Otto Rank and Hanns Sachs. Wilbur was also knowledgeable about the early reception of psychoanalysis in the Boston community.
and Models: A Self-Similar Approach
Directory of Open Access Journals (Sweden)
José Antonio Belinchón
2013-01-01
equations (FEs admit self-similar solutions. The methods employed allow us to obtain general results that are valid not only for the FRW metric, but also for all the Bianchi types as well as for the Kantowski-Sachs model (under the self-similarity hypothesis and the power-law hypothesis for the scale factors.
Anabalon, Andres
2016-01-01
In four dimensions, the most general metric admitting two Killing vectors and a rank-two Killing tensor can be parameterized by ten arbitrary functions of a single variable. We show that picking a special vierbien, reducing the system to eight functions, implies the existence of two geodesic and share-free, null congruences, generated by two principal null directions of the Weyl tensor. Thus, if the spacetime is an Einstein manifold, the Goldberg-Sachs theorem implies it is Petrov type D, and by explicit construction, is in the Carter class. Hence, our analysis provide an straightforward connection between the most general integrable structure and the Carter family of spacetimes.
National Tay-Sachs and Allied Diseases Association, Inc.
Exceptional Parent, 1977
1977-01-01
Reviewed are the history and organization, purpose and programs, and public services of the National Tay-Sachs and Allied Diseases Association, an organization geared toward eradicating Tay-Sachs disease (a hereditary disorder affecting primarily Jewish infants which generally leads to deterioration and death by the child's fifth year). (SBH)
The National Tay Sachs and Allied Diseases Association.
Zeitlin, Paula
1986-01-01
The National Tay-Sachs and Allied Diseases Association is involved in education, research, and prevention of Tay-Sachs, an inherited metabolic disorder which destroys the central nervous system, and over 30 related disorders. The group features a parent peer group network and a support group for carrier couples. (CL)
The National Tay Sachs and Allied Diseases Association.
Zeitlin, Paula
1986-01-01
The National Tay-Sachs and Allied Diseases Association is involved in education, research, and prevention of Tay-Sachs, an inherited metabolic disorder which destroys the central nervous system, and over 30 related disorders. The group features a parent peer group network and a support group for carrier couples. (CL)
National Tay-Sachs and Allied Diseases Association, Inc.
Exceptional Parent, 1977
1977-01-01
Reviewed are the history and organization, purpose and programs, and public services of the National Tay-Sachs and Allied Diseases Association, an organization geared toward eradicating Tay-Sachs disease (a hereditary disorder affecting primarily Jewish infants which generally leads to deterioration and death by the child's fifth year). (SBH)
Integrated Sachs-Wolfe effect in massive bigravity
Enander, Jonas; Mortsell, Edvard; Renneby, Malin; Solomon, Adam R
2015-01-01
We study the Integrated Sachs-Wolfe (ISW) effect in ghost-free, massive bigravity, where only one metric couples to matter. We focus on the infinite-branch bigravity (IBB) model which exhibits viable cosmic expansion histories and stable linear perturbations, while the cosmological constant is set to zero and the late-time accelerated expansion of the Universe is due solely to the gravitational interaction terms. The ISW contribution to the CMB auto-correlation power spectrum is predicted, as well as the cross-correlation between the CMB temperature anisotropies and the large-scale structure. We use ISW amplitudes as observed in the WMAP 9-year temperature data together with galaxy and AGN data provided by the WISE mission, in order to compare the theoretical predictions to the observations. The ISW amplitudes in IBB are found to be larger than the corresponding ones in the standard LCDM model by roughly a factor of 1.5, but are still consistent with the observations.
Julius Sachs (1832-1897) and the Unity of Life.
Kutschera, Ulrich; Baluška, František
2015-01-01
In 1865, the German botanist Julius Sachs published a seminal monograph entitled Experimental-Physiologie der Pflanzen (Experimental Physiology of Plants) and hence became the founder of a new scientific discipline that originated 150 y ago. Here, we outline the significance of the achievements of Sachs. In addition, we document, with reference to his Vorlesungen über Pflanzen-Physiologie (Lectures on the Physiology of Plants, 1882), that Sachs was one of the first experimentalists who proposed the functional unity of all organisms alive today (humans, animals, plants and other "vegetable" organisms, such as algae, cyanophyceae, fungi, myxomycetes, and bacteria).
Tay Sachs and Related Storage Diseases: Family Planning
Schneiderman, Gerald; And Others
1978-01-01
Based on interviews with 24 families, the article discusses family planning and the choices available to those families in which a child has previously died from Tay-Sachs or related lipid storage diseases. (IM)
Tay Sachs and Related Storage Diseases: Family Planning
Schneiderman, Gerald; And Others
1978-01-01
Based on interviews with 24 families, the article discusses family planning and the choices available to those families in which a child has previously died from Tay-Sachs or related lipid storage diseases. (IM)
Kroon, Cindy D.
2007-01-01
Created for a Metric Day activity, Metric Madness is a board game for two to four players. Students review and practice metric vocabulary, measurement, and calculations by playing the game. Playing time is approximately twenty to thirty minutes.
75 FR 44031 - Goldman, Sachs & Co., et al.; Notice of Application and Temporary Order
2010-07-27
... Management International (``GSAMI''), Goldman Sachs Hedge Fund Strategies LLC (``GSHFS''), Commonwealth... global investment banking and securities firm. Goldman Sachs is registered as an investment adviser with... marketing materials used in connection with residential mortgage-related securities offerings by...
Measuring the integrated Sachs-Wolfe effect
Dupé, F.-X.; Rassat, A.; Starck, J.-L.; Fadili, M. J.
2011-10-01
Context. One of the main challenges of modern cosmology is to understand the nature of the mysterious dark energy that causes the cosmic acceleration. The integrated Sachs-Wolfe (ISW) effect is sensitive to dark energy, and if detected in a universe where modified gravity and curvature are excluded, presents an independent signature of dark energy. The ISW effect occurs on large scales where cosmic variance is high and where owing to the Galactic confusion we lack large amounts of data in the CMB as well as large-scale structure maps. Moreover, existing methods in the literature often make strong assumptions about the statistics of the underlying fields or estimators. Together these effects can severely limit signal extraction. Aims: We aim to define an optimal statistical method for detecting the ISW effect that can handle large areas of missing data and minimise the number of underlying assumptions made about the data and estimators. Methods: We first review current detections (and non-detections) of the ISW effect, comparing statistical subtleties between existing methods, and identifying several limitations. We propose a novel method to detect and measure the ISW signal. This method assumes only that the primordial CMB field is Gaussian. It is based on a sparse inpainting method to reconstruct missing data and uses a bootstrap technique to avoid assumptions about the statistics of the estimator. It is a complete method, which uses three complementary statistical methods. Results: We apply our method to Euclid-like simulations and show we can expect a ~7σ model-independent detection of the ISW signal with WMAP7-like data, even when considering missing data. Other tests return ~5σ detection levels for a Euclid-like survey. We find that detection levels are independent from whether the galaxy field is normally or lognormally distributed. We apply our method to the 2 Micron All Sky Survey (2MASS) and WMAP7 CMB data and find detections in the 1.0-1.2σ range, as
Rapid detection of fetal Mendelian disorders: Tay-Sachs disease.
Guetta, Esther; Peleg, Leah
2008-01-01
Tay-Sachs disease is an autosomal recessive storage disease caused by the impaired activity of the lysosomal enzyme hexosaminidase A. In this fatal disease, the sphingolipid GM2 ganglioside accumulates in the neurons. Due to high carrier rates and the severity of the disease, population screening and prenatal diagnosis of Tay-Sachs disease are routinely carried out in Israel. Laboratory diagnosis of Tay-Sachs is carried out with biochemical and DNA-based methods in peripheral and umbilical cord blood, amniotic fluid, and chorionic villi samples. The assay of hexosaminidase A (Hex A) activity is carried out with synthetic substrates, 4-methylumbelliferyl-6-sulfo-N-acetyl-beta-glucosaminide (4-MUGS) and 4-methylumbelliferil-N-acetyl-beta-glucosamine (4-MUG), and the DNA-based analysis involves testing for the presence of specific known mutations in the alpha-subunit gene of Hex A. Prenatal diagnosis of Tay-Sachs disease is accomplished within 24-48 h from sampling. The preferred strategy is to simultaneously carry out enzymatic analysis in the amniotic fluid supernatant or in chorionic villi and molecular DNA-based testing in an amniotic fluid cell-pellet or in chorionic villi.
Klauder, J R
1998-01-01
Canonical quantization may be approached from several different starting points. The usual approaches involve promotion of c-numbers to q-numbers, or path integral constructs, each of which generally succeeds only in Cartesian coordinates. All quantization schemes that lead to Hilbert space vectors and Weyl operators---even those that eschew Cartesian coordinates---implicitly contain a metric on a flat phase space. This feature is demonstrated by studying the classical and quantum ``aggregations'', namely, the set of all facts and properties resident in all classical and quantum theories, respectively. Metrical quantization is an approach that elevates the flat phase space metric inherent in any canonical quantization to the level of a postulate. Far from being an unwanted structure, the flat phase space metric carries essential physical information. It is shown how the metric, when employed within a continuous-time regularization scheme, gives rise to an unambiguous quantization procedure that automatically ...
Emergence of product of constant curvature spaces in loop quantum cosmology
Dadhich, Naresh; Singh, Parampreet
2015-01-01
The loop quantum dynamics of Kantowski-Sachs spacetime and the interior of higher genus black hole spacetimes with a cosmological constant has some peculiar features not shared by various other spacetimes in loop quantum cosmology. As in the other cases, though the quantum geometric effects resolve the physical singularity and result in a non-singular bounce, after the bounce a spacetime with small spacetime curvature does not emerge in either the subsequent backward or the forward evolution. Rather, in the asymptotic limit the spacetime manifold is a product of two constant curvature spaces. Interestingly, though the spacetime curvature of these asymptotic spacetimes is very high, their effective metric is a solution to the Einstein's field equations. Analysis of the components of the Ricci tensor shows that after the singularity resolution, the Kantowski-Sachs spacetime leads to an effective metric which can be interpreted as the `charged' Nariai, while the higher genus black hole interior can similarly be ...
2012-11-01
As the old 'publish or perish' adage is brought into question, additional research-impact indices, known as altmetrics, are offering new evaluation alternatives. But such metrics may need to adjust to the evolution of science publishing.
Modified Sachs's Model of Deformation of Polycrystalline Magnesium
Kesarev, A. G.; Vlasova, A. M.
2017-09-01
There are a large number of approaches to a description of work hardening of metal polycrystals with various crystal lattices. In the present work, Sachs's model is generalized to uniaxial tension/compression of polycrystalline magnesium with hexagonal densely packed crystal lattice. The tensile yield stress is estimated taking into account two deformation modes: (0001) easy basal slip and (10\\overline{1}2) twinning.
Noncommutative Quantum Cosmology
García-Compéan, H; Ramírez, C
2001-01-01
We propose a model for noncommutative quantum cosmology by means of a deformation of minisuperspace. For the Kantowski-Sachs metric we are able to find the exact solution to the deformed Wheeler-DeWitt equation. We construct wave packets and show that noncommutativity could remarkably modify the quantum behavior of the universe. We discuss the relation with space-time noncommutativity and exhibit a program to search for the influence of noncommutativity at early times in the universe.
Multidimensional Global Monopole and Nonsingular Cosmology
Bronnikov, K A; Bronnikov, Kirill A.; Meierovich, Boris E.
2003-01-01
We consider a spherically symmetric global monopole in general relativity in $(D=d+2)$-dimensional spacetime. The monopole is shown to be asymptotically flat up to a solid angle defect in case $\\gamma < d-1$, where $\\gamma$ is a parameter characterizing the gravitational field strength. In the range $d-1< \\gamma < 2d(d+1)/(d+2)$ the monopole space-time contains a cosmological horizon. Outside the horizon the metric corresponds to a cosmological model of Kantowski-Sachs type, where spatial sections have the topology ${\\R\\times \\S}^d$. In the important case when the horizon is far from the monopole core, the temporal evolution of the Kantowski-Sachs metric is described analytically. The Kantowski-Sachs space-time contains a subspace with a $(d+1)$-dimensional Friedmann-Robertson-Walker metric, and its possible cosmological application is discussed. Some numerical estimations in case $d=3$ are made showing that this class of nonsingular cosmologies can be viable. Other results, generalizing those known ...
Bellet, Aurelien; Sebban, Marc
2015-01-01
Similarity between objects plays an important role in both human cognitive processes and artificial systems for recognition and categorization. How to appropriately measure such similarities for a given task is crucial to the performance of many machine learning, pattern recognition and data mining methods. This book is devoted to metric learning, a set of techniques to automatically learn similarity and distance functions from data that has attracted a lot of interest in machine learning and related fields in the past ten years. In this book, we provide a thorough review of the metric learnin
Testing cosmological models with the Integrated Sachs-Wolfe effect
Energy Technology Data Exchange (ETDEWEB)
Raccanelli, Alvise, E-mail: alvise.raccanelli@port.ac.uk [Institute of Cosmology and Gravitation, University of Portsmouth, Dennis Sciama Building, Portsmouth, PO1 3FX (United Kingdom)
2011-02-01
The cross correlation between the Cosmic Microwave Background and the Large Scale Structure of the Universe is a powerful probe to test our cosmological models. This correlation can be used to detect the Integrated Sachs-Wolfe effect, and it depends on both the geometry of the Universe and the properties of the clustering and evolution of structures; for this reason it can be used to test and constrain cosmological models and parameters as well as theories of gravity. In this proceeding we briefly introduce the ISW effect and present some of the recent cosmological tests done using it.
Quevedo, Hernando
2016-01-01
We review the problem of describing the gravitational field of compact stars in general relativity. We focus on the deviations from spherical symmetry which are expected to be due to rotation and to the natural deformations of mass distributions. We assume that the relativistic quadrupole moment takes into account these deviations, and consider the class of axisymmetric static and stationary quadrupolar metrics which satisfy Einstein's equations in empty space and in the presence of matter represented by a perfect fluid. We formulate the physical conditions that must be satisfied for a particular spacetime metric to describe the gravitational field of compact stars. We present a brief review of the main static and axisymmetric exact solutions of Einstein's vacuum equations, satisfying all the physical conditions. We discuss how to derive particular stationary and axisymmetric solutions with quadrupolar properties by using the solution generating techniques which correspond either to Lie symmetries and B\\"acku...
Rapid identification of HEXA mutations in Tay-Sachs patients.
Giraud, Carole; Dussau, Jeanne; Azouguene, Emilie; Feillet, François; Puech, Jean-Philippe; Caillaud, Catherine
2010-02-19
Tay-Sachs disease (TSD) is a recessively inherited neurodegenerative disorder due to mutations in the HEXA gene resulting in a beta-hexosaminidase A (Hex A) deficiency. The purpose of this study was to characterize the molecular abnormalities in patients with infantile or later-onset forms of the disease. The complete sequencing of the 14 exons and flanking regions of the HEXA gene was performed with a unique technical condition in 10 unrelated TSD patients. Eleven mutations were identified, including five splice mutations, one insertion, two deletions and three single-base substitutions. Four mutations were novel: two splice mutations (IVS8+5G>A, IVS2+4delAGTA), one missense mutation in exon 6 (c.621T>G (p.D207E)) and one small deletion (c.1211-1212delTG) in exon 11 resulting in a premature stop codon at residue 429. The c.621T>G missense mutation was found in a patient presenting an infantile form. Its putative role in the pathogenesis of TSD is suspected as residue 207 is highly conserved in human, mouse and rat. Moreover, structural modelling predicted changes likely to affect substrate binding and catalytic activity of the enzyme. The time-saving procedure reported here could be useful for the characterization of Tay-Sachs-causing mutations, in particular in non-Ashkenazi patients mainly exhibiting rare mutations.
Structural consequences of amino acid substitutions causing Tay-Sachs disease.
Ohno, Kazuki; Saito, Seiji; Sugawara, Kanako; Sakuraba, Hitoshi
2008-08-01
To determine the structural changes in the alpha-subunit of beta-hexosaminidase due to amino acid substitutions causing Tay-Sachs disease, we built structural models of mutant alpha-subunits resulting from 33 missense mutations (24 infantile and 9 late-onset), and analyzed the influence of each amino acid replacement on the structure by calculating the number of atoms affected and determining the solvent-accessible surface area of the corresponding amino acid residue in the wild-type alpha-subunit. In the infantile Tay-Sachs group, the number of atoms influenced by a mutation was generally larger than that in the late-onset Tay-Sachs group in both the main chain and the side chain, and residues associated with the mutations found in the infantile Tay-Sachs group tended to be less solvent-accessible than those in the late-onset Tay-Sachs group. Furthermore, color imaging determined the distribution and degree of the structural changes caused by representative amino acid substitutions, and that there were also differences between the infantile and late-onset Tay-Sachs disease groups. Structural study is useful for elucidating the basis of Tay-Sachs disease.
Comparison of the Sachs-Wolfe Effect for Gaussian and Non-Gaussian Fluctuations
Kung, J H
1993-01-01
A consequence of non-Gaussian perturbations on the Sachs-Wolfe effect is studied. For a particular power spectrum, predicted Sachs-Wolfe effects are calculated for two cases: Gaussian (random phase) configuration, and a specific kind of non-Gaussian configuration. We obtain a result that the Sachs-Wolfe effect for the latter case is smaller when each temperature fluctuation is properly normalized with respect to the corresponding mass fluctuation ${\\delta M\\over M}(R)$. The physical explanation and the generality of the result are discussed.
Conserved charges of the extended Bondi-Metzner-Sachs group
Flanagan, Eanna E
2015-01-01
Isolated objects in asymptotically flat spacetimes in general relativity are characterized by their conserved charges associated with the Bondi-Metzner-Sachs (BMS) group. These charges include total energy, linear momentum, intrinsic angular momentum and center-of-mass location, and in addition an infinite number of supermomentum charges associated with supertranslations. Recently it has been suggested that the BMS symmetry algebra should be enlarged to include an infinite number of additional symmetries known as superrotations. We compute the corresponding "super center-of-mass'' charges and show that they are finite and well defined. The supermomentum charges are associated with ordinary gravitational wave memory, and the super center-of-mass charges are associated with total (ordinary plus null) gravitational wave memory, in the terminology of Bieri and Garfinkle. Some of these charges can give rise to black hole hair, as described by Strominger and Zhiboedov. We clarify how this hair evades the no hair th...
Planck 2015 results: XXI. The integrated Sachs-Wolfe effect
DEFF Research Database (Denmark)
Ade, P. A R; Aghanim, N.; Arnaud, M.
2016-01-01
This paper presents a study of the integrated Sachs-Wolfe (ISW) effect from the Planck 2015 temperature and polarization data release. This secondary cosmic microwave background (CMB) anisotropy caused by the large-scale time-evolving gravitational potential is probed from different perspectives....... The CMB is cross-correlated with different large-scale structure (LSS) tracers: radio sources from the NVSS catalogue; galaxies from the optical SDSS and the infrared WISE surveys; and the Planck 2015 convergence lensing map. The joint cross-correlation of the CMB with the tracers yields a detection at 4σ...... scales available in the 2015 release do not permit significant improvement of the CMB-LSS cross-correlation detectability. Nevertheless, the Planck polarization data are used to study the anomalously large ISW signal previously reported through the aperture photometry on stacked CMB features...
Numerical Relativity and the Bondi-Metzner-Sachs Group
Winicour, Jeffrey
2017-01-01
There are interesting phenomena associated with the Bondi-Metzner-Sachs (BMS) group that deserve numerical exploration. The BMS group, which is the asymptotic symmetry group of an isolated gravitational system, extends the Poincare group by the addition of an infinite set of supertranslations parameterized by a function on the sphere α(θ , ϕ) . The l = 0 and l = 1 spherical harmonics invariantly pick out the time and space translations, which leads to an unambiguous definition of energy and momentum. However, a Poincare subgroup cannot be invariantly defined, which leads to a supertranslation ambiguity in the definition of angular momentum. This opens the possibility of a purely general relativistic mechanism for angular momentum loss. The supertranslations are also associated with the gravitational memory effect. I will discuss these problems which are ripe for the numerical simulation of high spin black hole binaries. Supported by NSF grant PHY-1505965 to the University of Pittsburgh.
Tay-Sachs disease: current perspectives from Australia.
Lew, Raelia M; Burnett, Leslie; Proos, Anné L; Delatycki, Martin B
2015-01-01
Tay-Sachs disease (TSD) is a fatal, recessively inherited neurodegenerative condition of infancy and early childhood. Although rare in most other populations, the carrier frequency is one in 25 in Ashkenazi Jews. Australian high-school-based TSD preconception genetic screening programs aim to screen, educate, and optimize reproductive choice for participants. These programs have demonstrated high uptake, low psychological morbidity, and have been shown to result in fewer than expected Jewish TSD-affected births over 18 years of operation. The majority of Jewish individuals of reproductive age outside of the high school screening program setting in Australia have not accessed screening. Recent recommendations advocate supplementing the community high school screening programs with general practitioner- and obstetrician-led genetic screening of Ashkenazi Jewish individuals for TSD and other severe recessive diseases for which this group is at risk. Massively parallel DNA sequencing is expected to become the testing modality of choice over the coming years.
Atypical presentation of late-onset Tay-Sachs disease.
Deik, Andres; Saunders-Pullman, Rachel
2014-05-01
Late-onset Tay-Sachs disease (LOTS) is a lysosomal storage disease caused by deficient Beta-hexosaminidase A activity. We describe a 53-year-old woman who presented with adult-onset leg weakness, and whose initial diagnosis was progressive muscular atrophy without identifiable etiology. Development of cerebellar ataxia in mid-life prompted reassessment. Beta-hexosaminidase A quantification assay demonstrated absence of the isozyme. Genetic testing identified compound heterozygous mutations in the HEXA gene, confirming the diagnosis of LOTS. The phenotypic spectrum of LOTS includes motor neuronopathy, ataxia, choreoathetosis, neuropathy, and psychiatric symptoms in various combinations. This patient highlights the emergence of different clinical features over many years and emphasizes the need to consider LOTS in the differential diagnosis of progressive muscular atrophy. Copyright © 2013 Wiley Periodicals, Inc.
Planck 2013 results. XIX. The integrated Sachs-Wolfe effect
DEFF Research Database (Denmark)
Ade, P. A. R.; Aghanim, N.; Armitage-Caplan, C.
2014-01-01
Based on cosmic microwave background (CMB) maps from the 2013 Planck Mission data release, this paper presents the detection of the integrated Sachs-Wolfe (ISW) effect, that is, the correlation between the CMB and large-scale evolving gravitational potentials. The significance of detection ranges...... from 2 to 4σ, depending on which method is used. We investigated three separate approaches, which essentially cover all previous studies, and also break new ground. (i) We correlated the CMB with the Planck reconstructed gravitational lensing potential (for the first time). This detection was made...... on a combination of radio (NVSS) and optical (SDSS) data. (iii) We used aperture photometry on stacked CMB fields at the locations of known large-scale structures, which yielded and confirms a 4σ signal, over a broader spectral range, when using a previously explored catalogue, but shows strong discrepancies...
Tay-Sachs disease: current perspectives from Australia
Directory of Open Access Journals (Sweden)
Lew RM
2015-01-01
Full Text Available Raelia M Lew,1,7 Leslie Burnett,2,3,4 Anné L Proos,2 Martin B Delatycki5,6 1Department of Obstetrics and Gynecology, QEII Research Institute for Mothers and Infants, The University of Sydney, Australia; 2NSW Health Pathology North, Royal North Shore Hospital, St Leonards, Australia; 3SEALS, Prince of Wales Hospital, Randwick, Australia; 4Sydney Medical School-Northern, Royal North Shore Hospital E25, University of Sydney, Sydney, Australia; 5Department of Clinical Genetics, Austin Health, Heidelberg, Australia; 6Bruce Lefroy Centre for Genetic Health Research, Murdoch Childrens Research Institute, Parkville, Australia; 7Department of Obstetrics and Gynaecology, Dentistry and Health Sciences, Faculty of Medicine, The University of Melbourne, Melbourne, Australia Abstract: Tay-Sachs disease (TSD is a fatal, recessively inherited neurodegenerative condition of infancy and early childhood. Although rare in most other populations, the carrier frequency is one in 25 in Ashkenazi Jews. Australian high-school-based TSD preconception genetic screening programs aim to screen, educate, and optimize reproductive choice for participants. These programs have demonstrated high uptake, low psychological morbidity, and have been shown to result in fewer than expected Jewish TSD-affected births over 18 years of operation. The majority of Jewish individuals of reproductive age outside of the high school screening program setting in Australia have not accessed screening. Recent recommendations advocate supplementing the community high school screening programs with general practitioner- and obstetrician-led genetic screening of Ashkenazi Jewish individuals for TSD and other severe recessive diseases for which this group is at risk. Massively parallel DNA sequencing is expected to become the testing modality of choice over the coming years. Keywords: Tay-Sachs disease, genetic screening, Australia
Tay-Sach disease with "cherry-red spot"--first reported case in Malaysia.
Chan, L Y; Balasubramaniam, S; Sunder, R; Jamalia, R; Karunakar, T V N; Alagaratnam, J
2011-12-01
We present a rare case of Tay-Sachs disease with retinal 'cherry-red spots' in a 19-month-old Malay child. Molecular genetic studies confirmed the diagnosis. The case highlights that 'cherry-red spot' is a useful clinical clue in Tay-Sachs disease and several other lysosomal storage disorders. It serves as an ideal illustration of the eye as a window to inborn error of metabolism.
Correlation between Bankart and Hill-Sachs lesions in anterior shoulder dislocation.
Widjaja, Audi B; Tran, Anh; Bailey, Michael; Proper, Stewart
2006-06-01
Bankart lesions and Hill-Sachs lesions are commonly associated with anterior shoulder dislocations. The presence of Bankart lesion indicates the need for surgical repair. Magnetic resonance imaging (MRI) has been shown to be sensitive in detecting these two lesions. The aim of this study is to investigate the correlation between Bankart lesions and Hill-Sachs lesions on MRI for patients with traumatic anterior shoulder dislocations. Between 2003 and 2005, 61 patients from Alfred and Sandringham Hospitals had an MRI as part of the investigation for traumatic anterior shoulder dislocations. The MRI scans were reviewed and subsequently confirmed by a radiologist to show the presence or absence of Bankart and Hill-Sachs lesions. The data were then analysed by a statistician. Although patients with one of these lesions were more than two-and-a-half times as likely to have the other, small study numbers precluded this result from achieving statistical significance. (odds ratio, 2.67 (0.83-8.61), P = 0.10). Younger age was a strong predictor of a recurrence of shoulder dislocation (odds ratio, 0.93 (0.89-0.98), P = 0.005). The presence of Bankart or Hill-Sachs lesions on MRI for the primary shoulder dislocation group was similar to the recurrent group (73% vs. 72% for Bankart lesion and 67% vs. 70% for Hill-Sachs lesion). There is a strong correlation between both lesions. This apparent trend can be useful in predicting the presence of a Bankart lesion when a Hill-Sachs lesion is identified on a plain radiograph. This study suggests the consideration of surgical repair after identification of a Hill-Sachs lesion on plain radiographs, especially for younger patients where the rate of re-dislocation is high.
The High Redshift Integrated Sachs-Wolfe Effect
Xia, Jun-Qing; Baccigalupi, Carlo; Matarrese, Sabino
2009-01-01
In this paper we rely on the quasar (QSO) catalog of the Sloan Digital Sky Survey Data Release Six (SDSS DR6) of about one million photometrically selected QSOs to compute the Integrated Sachs-Wolfe (ISW) effect at high redshift, aiming at constraining the behavior of the expansion rate and thus the behaviour of dark energy at those epochs. This unique sample significantly extends previous catalogs to higher redshifts while retaining high efficiency in the selection algorithm. We compute the auto-correlation function (ACF) of QSO number density from which we extract the bias and the stellar contamination. We then calculate the cross-correlation function (CCF) between QSO number density and Cosmic Microwave Background (CMB) temperature fluctuations in different subsamples: at high z>1.5 and low z1.5. We focus on the capabilities of the ISW to constrain the behaviour of the dark energy component at high redshift both in the \\LambdaCDM and Early Dark Energy cosmologies, when the dark energy is substantially unco...
Reconstructing the integrated Sachs-Wolfe map with galaxy surveys
Muir, Jessica; Huterer, Dragan
2016-08-01
The integrated Sachs-Wolfe (ISW) effect is a large-angle modulation of the cosmic microwave background (CMB), generated when CMB photons traverse evolving potential wells associated with large scale structure (LSS). Recent efforts have been made to reconstruct maps of the ISW signal using information from surveys of galaxies and other LSS tracers, but investigation into how survey systematics affect their reliability has so far been limited. Using simulated ISW and LSS maps, we study the impact of galaxy survey properties and systematic errors on the accuracy of a reconstructed ISW signal. We find that systematics that affect the observed distribution of galaxies along the line of sight, such as photo-z and bias-evolution related errors, have a relatively minor impact on reconstruction quality. In contrast, however, we find that direction-dependent calibration errors can be very harmful. Specifically, we find that, in order to avoid significant degradation of our reconstruction quality statistics, direction-dependent number density fluctuations due to systematics must be controlled so that their variance is smaller than 10-6 (which corresponds to a 0.1% calibration). Additionally, we explore the implications of our results for attempts to use reconstructed ISW maps to shed light on the origin of large-angle CMB alignments. We find that there is only a weak correlation between the true and reconstructed angular momentum dispersion, which quantifies alignment, even for reconstructed ISW maps which are fairly accurate overall.
Conserved charges of the extended Bondi-Metzner-Sachs algebra
Flanagan, Éanna É.; Nichols, David A.
2017-02-01
Isolated objects in asymptotically flat spacetimes in general relativity are characterized by their conserved charges associated with the Bondi-Metzner-Sachs (BMS) group. These charges include total energy, linear momentum, intrinsic angular momentum and center-of-mass location, and, in addition, an infinite number of supermomentum charges associated with supertranslations. Recently, it has been suggested that the BMS symmetry algebra should be enlarged to include an infinite number of additional symmetries known as super-rotations. We show that the corresponding charges are finite and well defined, and can be divided into electric parity "super center-of-mass" charges and magnetic parity "superspin" charges. The supermomentum charges are associated with ordinary gravitational-wave memory, and the super center-of-mass charges are associated with total (ordinary plus null) gravitational-wave memory, in the terminology of Bieri and Garfinkle. Superspin charges are associated with the ordinary piece of spin memory. Some of these charges can give rise to black hole hair, as described by Strominger and Zhiboedov. We clarify how this hair evades the no-hair theorems.
Basic versus applied research: Julius Sachs (1832-1897) and the experimental physiology of plants.
Kutschera, Ulrich
2015-01-01
The German biologist Julius Sachs was the first to introduce controlled, accurate, quantitative experimentation into the botanical sciences, and is regarded as the founder of modern plant physiology. His seminal monograph Experimental-Physiologie der Pflanzen (Experimental Physiology of Plants) was published 150 y ago (1865), when Sachs was employed as a lecturer at the Agricultural Academy in Poppelsdorf/Bonn (now part of the University). This book marks the beginning of a new era of basic and applied plant science. In this contribution, I summarize the achievements of Sachs and outline his lasting legacy. In addition, I show that Sachs was one of the first biologists who integrated bacteria, which he considered to be descendants of fungi, into the botanical sciences and discussed their interaction with land plants (degradation of wood etc.). This "plant-microbe-view" of green organisms was extended and elaborated by the laboratory botanist Wilhelm Pfeffer (1845-1920), so that the term "Sachs-Pfeffer-Principle of Experimental Plant Research" appears to be appropriate to characterize this novel way of performing scientific studies on green, photoautotrophic organisms (embryophytes, algae, cyanobacteria).
[Tay-Sachs disease in non-Jewish infant in Israel].
Nadim, Nasser
2012-01-01
Tay-Sachs disease, also known as GM2 gangliosidosis or Hexosaminidase A deficiency is an autosomal recessive genetic fatal disorder. The disease is known to appear in East European Ashkenazi Jews, North African Jews, and Quebec French Canadians exclusively, but, with different frequency and type of mutation. Its most common variant is the infantile type Tay-Sachs disease. Juvenile and late-onset forms of the disease are infrequent and slowly progressive. At nearly 3 to 6 months old, a baby with Tay-Sachs progressively loses his motor skills and attentiveness. Startle responses and hyperreflexia become prominent, especially on eliciting deep patellar and Achilles reflexes, as a consequence of neurodegeneration of the upper motor neuron. Other systemic damage ensues gradually; seizures, blindness, spasticity of limbs, inability to swallow and breathe, and eventually the baby dies at 1-4 years of age. All Tay-Sachs patients have a "cherry red spot", easily seen in the macula area of the retina, using an ophthalmoscope. The "cherry red spot" is the only normal part of the retina in these sick babies. The case presented here emphasizes that Tay-Sachs disease is sometimes misdiagnosed at first visits even by an experienced clinician, because of his lack of awareness that this disease is not exclusively a Jewish disease.
Locher, Joel; Wilken, Frauke; Beitzel, Knut; Buchmann, Stefan; Longo, Umile Giuseppe; Denaro, Vincenzo; Imhoff, Andreas B
2016-10-01
To evaluate the effect of "off-track" Hill-Sachs lesions, according to the glenoid track concept, as a risk factor for recurrent instability and need for revision surgery after arthroscopic Bankart repair. We retrospectively reviewed 254 patients with anteroinferior glenohumeral instability who were managed with an arthroscopic stabilization procedure between 2006 and 2013. Preoperative magnetic resonance imaging and/or computed tomography scans were available for 100 of these patients to calculate the glenoid track and the presence of "on-track" or off-track Hill-Sachs lesions. Recurrence of instability was evaluated at a mean follow-up of 22.4 months. Of 100 patients whose magnetic resonance imaging and/or computed tomography scans were available, 88 had an on-track Hill-Sachs lesion and 12 had an off-track Hill-Sachs lesion. Revision surgery for recurrent instability was performed in 5 patients (6%) with an on-track Hill-Sachs lesion and in 4 patients (33%) with an off-track Hill-Sachs lesion (odds ratio, 8.3; 95% confidence interval, 1.85-37.26; P = .006). An off-track Hill-Sachs lesion is a significant and important risk factor for recurrence of instability and need for revision surgery after arthroscopic Bankart repair when compared with an on-track Hill-Sachs lesion. Level IV, prognostic case series. Copyright © 2016 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.
Energy Technology Data Exchange (ETDEWEB)
Ferrari, Frank, E-mail: frank.ferrari@ulb.ac.be [Service de Physique Theorique et Mathematique, Universite Libre de Bruxelles and International Solvay Institutes, Campus de la Plaine, CP 231, 1050 Bruxelles (Belgium); Klevtsov, Semyon, E-mail: semyon.klevtsov@ulb.ac.be [Service de Physique Theorique et Mathematique, Universite Libre de Bruxelles and International Solvay Institutes, Campus de la Plaine, CP 231, 1050 Bruxelles (Belgium); ITEP, B. Cheremushkinskaya 25, Moscow 117218 (Russian Federation); Zelditch, Steve, E-mail: zelditch@math.northwestern.edu [Department of Mathematics, Northwestern University, Evanston, IL 60208 (United States)
2013-04-01
The purpose of this article is to propose a new method to define and calculate path integrals over metrics on a Kaehler manifold. The main idea is to use finite dimensional spaces of Bergman metrics, as an approximation to the full space of Kaehler metrics. We use the theory of large deviations to decide when a sequence of probability measures on the spaces of Bergman metrics tends to a limit measure on the space of all Kaehler metrics. Several examples are considered.
Bondi-Sachs energy-momentum and the energy of gravitational radiation
Maluf, J W; Ulhoa, S C
2015-01-01
We construct the gravitational energy-momentum of the Bondi-Sachs space-time, in the famework of the teleparallel equivalent of general relativity (TEGR). The Bondi-Sachs line element describes gravitational radiation in the asymptotic region of the space-time, and is determined by the mass aspect and by two functions, $c$ and $d$, that yield the news functions, which are interpreted as the radiating degrees of freedom of the gravitational field. The standard expression for the Bondi-Sachs energy-momentum is constructed in terms of the mass aspect only. The expression that we obtain in the context of the TEGR is given by the standard expression, which represents the gravitational energy of the source, plus a new term that is determined by the two functions $c$ and $d$. We interpret this new term as the energy of gravitational radiation.
Lyso-GM2 ganglioside: a possible biomarker of Tay-Sachs disease and Sandhoff disease.
Kodama, Takashi; Togawa, Tadayasu; Tsukimura, Takahiro; Kawashima, Ikuo; Matsuoka, Kazuhiko; Kitakaze, Keisuke; Tsuji, Daisuke; Itoh, Kohji; Ishida, Yo-Ichi; Suzuki, Minoru; Suzuki, Toshihiro; Sakuraba, Hitoshi
2011-01-01
To find a new biomarker of Tay-Sachs disease and Sandhoff disease. The lyso-GM2 ganglioside (lyso-GM2) levels in the brain and plasma in Sandhoff mice were measured by means of high performance liquid chromatography and the effect of a modified hexosaminidase (Hex) B exhibiting Hex A-like activity was examined. Then, the lyso-GM2 concentrations in human plasma samples were determined. The lyso-GM2 levels in the brain and plasma in Sandhoff mice were apparently increased compared with those in wild-type mice, and they decreased on intracerebroventricular administration of the modified Hex B. The lyso-GM2 levels in plasma of patients with Tay-Sachs disease and Sandhoff disease were increased, and the increase in lyso-GM2 was associated with a decrease in Hex A activity. Lyso-GM2 is expected to be a potential biomarker of Tay-Sachs disease and Sandhoff disease.
NASA science publications have used the metric system of measurement since 1970. Although NASA has maintained a metric use policy since 1979, practical constraints have restricted actual use of metric units. In 1988, an amendment to the Metric Conversion Act of 1975 required the Federal Government to adopt the metric system except where impractical. In response to Public Law 100-418 and Executive Order 12770, NASA revised its metric use policy and developed this Metric Transition Plan. NASA's goal is to use the metric system for program development and functional support activities to the greatest practical extent by the end of 1995. The introduction of the metric system into new flight programs will determine the pace of the metric transition. Transition of institutional capabilities and support functions will be phased to enable use of the metric system in flight program development and operations. Externally oriented elements of this plan will introduce and actively support use of the metric system in education, public information, and small business programs. The plan also establishes a procedure for evaluating and approving waivers and exceptions to the required use of the metric system for new programs. Coordination with other Federal agencies and departments (through the Interagency Council on Metric Policy) and industry (directly and through professional societies and interest groups) will identify sources of external support and minimize duplication of effort.
Planck 2015 results. XXI. The integrated Sachs-Wolfe effect
Planck Collaboration; Ade, P. A. R.; Aghanim, N.; Arnaud, M.; Ashdown, M.; Aumont, J.; Baccigalupi, C.; Banday, A. J.; Barreiro, R. B.; Bartolo, N.; Basak, S.; Battaner, E.; Benabed, K.; Benoît, A.; Benoit-Lévy, A.; Bernard, J.-P.; Bersanelli, M.; Bielewicz, P.; Bock, J. J.; Bonaldi, A.; Bonavera, L.; Bond, J. R.; Borrill, J.; Bouchet, F. R.; Bucher, M.; Burigana, C.; Butler, R. C.; Calabrese, E.; Cardoso, J.-F.; Casaponsa, B.; Catalano, A.; Challinor, A.; Chamballu, A.; Chiang, H. C.; Christensen, P. R.; Church, S.; Clements, D. L.; Colombi, S.; Colombo, L. P. L.; Combet, C.; Couchot, F.; Coulais, A.; Crill, B. P.; Curto, A.; Cuttaia, F.; Danese, L.; Davies, R. D.; Davis, R. J.; de Bernardis, P.; de Rosa, A.; de Zotti, G.; Delabrouille, J.; Désert, F.-X.; Diego, J. M.; Dole, H.; Donzelli, S.; Doré, O.; Douspis, M.; Ducout, A.; Dupac, X.; Efstathiou, G.; Elsner, F.; Enßlin, T. A.; Eriksen, H. K.; Fergusson, J.; Fernandez-Cobos, R.; Finelli, F.; Forni, O.; Frailis, M.; Fraisse, A. A.; Franceschi, E.; Frejsel, A.; Galeotta, S.; Galli, S.; Ganga, K.; Génova-Santos, R. T.; Giard, M.; Giraud-Héraud, Y.; Gjerløw, E.; González-Nuevo, J.; Górski, K. M.; Gratton, S.; Gregorio, A.; Gruppuso, A.; Gudmundsson, J. E.; Hansen, F. K.; Hanson, D.; Harrison, D. L.; Henrot-Versillé, S.; Hernández-Monteagudo, C.; Herranz, D.; Hildebrandt, S. R.; Hivon, E.; Hobson, M.; Holmes, W. A.; Hornstrup, A.; Hovest, W.; Huffenberger, K. M.; Hurier, G.; Ilić, S.; Jaffe, A. H.; Jaffe, T. R.; Jones, W. C.; Juvela, M.; Keihänen, E.; Keskitalo, R.; Kisner, T. S.; Kneissl, R.; Knoche, J.; Kunz, M.; Kurki-Suonio, H.; Lagache, G.; Lähteenmäki, A.; Lamarre, J.-M.; Langer, M.; Lasenby, A.; Lattanzi, M.; Lawrence, C. R.; Leonardi, R.; Lesgourgues, J.; Levrier, F.; Liguori, M.; Lilje, P. B.; Linden-Vørnle, M.; López-Caniego, M.; Lubin, P. M.; Ma, Y.-Z.; Macías-Pérez, J. F.; Maggio, G.; Maino, D.; Mandolesi, N.; Mangilli, A.; Marcos-Caballero, A.; Maris, M.; Martin, P. G.; Martínez-González, E.; Masi, S.; Matarrese, S.; McGehee, P.; Meinhold, P. R.; Melchiorri, A.; Mendes, L.; Mennella, A.; Migliaccio, M.; Mitra, S.; Miville-Deschênes, M.-A.; Moneti, A.; Montier, L.; Morgante, G.; Mortlock, D.; Moss, A.; Munshi, D.; Murphy, J. A.; Naselsky, P.; Nati, F.; Natoli, P.; Netterfield, C. B.; Nørgaard-Nielsen, H. U.; Noviello, F.; Novikov, D.; Novikov, I.; Oxborrow, C. A.; Paci, F.; Pagano, L.; Pajot, F.; Paoletti, D.; Pasian, F.; Patanchon, G.; Perdereau, O.; Perotto, L.; Perrotta, F.; Pettorino, V.; Piacentini, F.; Piat, M.; Pierpaoli, E.; Pietrobon, D.; Plaszczynski, S.; Pointecouteau, E.; Polenta, G.; Popa, L.; Pratt, G. W.; Prézeau, G.; Prunet, S.; Puget, J.-L.; Rachen, J. P.; Reach, W. T.; Rebolo, R.; Reinecke, M.; Remazeilles, M.; Renault, C.; Renzi, A.; Ristorcelli, I.; Rocha, G.; Rosset, C.; Rossetti, M.; Roudier, G.; Rubiño-Martín, J. A.; Rusholme, B.; Sandri, M.; Santos, D.; Savelainen, M.; Savini, G.; Schaefer, B. M.; Scott, D.; Seiffert, M. D.; Shellard, E. P. S.; Spencer, L. D.; Stolyarov, V.; Stompor, R.; Sudiwala, R.; Sunyaev, R.; Sutton, D.; Suur-Uski, A.-S.; Sygnet, J.-F.; Tauber, J. A.; Terenzi, L.; Toffolatti, L.; Tomasi, M.; Tristram, M.; Tucci, M.; Tuovinen, J.; Valenziano, L.; Valiviita, J.; Van Tent, F.; Vielva, P.; Villa, F.; Wade, L. A.; Wandelt, B. D.; Wehus, I. K.; Yvon, D.; Zacchei, A.; Zonca, A.
2016-09-01
This paper presents a study of the integrated Sachs-Wolfe (ISW) effect from the Planck 2015 temperature and polarization data release. This secondary cosmic microwave background (CMB) anisotropy caused by the large-scale time-evolving gravitational potential is probed from different perspectives. The CMB is cross-correlated with different large-scale structure (LSS) tracers: radio sources from the NVSS catalogue; galaxies from the optical SDSS and the infrared WISE surveys; and the Planck 2015 convergence lensing map. The joint cross-correlation of the CMB with the tracers yields a detection at 4σ where most of the signal-to-noise is due to the Planck lensing and the NVSS radio catalogue. In fact, the ISW effect is detected from the Planck data only at ≈3σ (through the ISW-lensing bispectrum), which is similar to the detection level achieved by combining the cross-correlation signal coming from all the galaxy catalogues mentioned above. We study the ability of the ISW effect to place constraints on the dark-energy parameters; in particular, we show that ΩΛ is detected at more than 3σ. This cross-correlation analysis is performed only with the Planck temperature data, since the polarization scales available in the 2015 release do not permit significant improvement of the CMB-LSS cross-correlation detectability. Nevertheless, the Planck polarization data are used to study the anomalously large ISW signal previously reported through the aperture photometry on stacked CMB features at the locations of known superclusters and supervoids, which is in conflict with ΛCDM expectations. We find that the current Planck polarization data do not exclude that this signal could be caused by the ISW effect. In addition, the stacking of the Planck lensing map on the locations of superstructures exhibits a positive cross-correlation with these large-scale structures. Finally, we have improved our previous reconstruction of the ISW temperature fluctuations by combining the
Energy in the Kantowski–Sachs space-time using teleparallel geometry
Indian Academy of Sciences (India)
Anuradha Das Purkayastha
2013-04-01
The purpose of this paper is to examine the energy content of the inflationary Universe described by Kantowski–Sachs space-time in quasilocal approach of teleparallel gravity and in the Hamiltonian structure of the teleparallel equivalent of general relativity. The teleparallel versions of field equations are also derived in such a space-time.
Iconicity as the key to the poetry of Nelly Sachs (1891-1970
Directory of Open Access Journals (Sweden)
H. Ester
2011-06-01
Full Text Available In her poetry Nelly Sachs tried to overcome all obstaclesi in order to speak about the unspeakable. Words that could adequately embody the horrors of the Nazi concentration camps were lacking. Nevertheless, it was necessary to speak about the experience for the sake of both herself and other victims of the camps. Through her poetry Sachs tests the validity and strength of both traditional images and biblical stories about suffering and grace. Words and images enable her to touch the experiences of people. However, she questions the generally accepted meaning of words in German. Her use of language strives to be different and to draw the attention to both the difficulties and risks of writing authentic words with the necessary symbolic strength. Sachs’ mental fragility made her very vulnerable and caused her to walk on the edge of total silence. As a consequence of her vulnerability, she tried with her whole heart to gain Paul Celan’s sympathy for her way of writing and efforts to turn the events in the concentration camps into dignified and true poetry. The relationship between Celan and Sachs reveals that the true meaning of poetry in her life was a manner of survival. The differences between the two poets provide insight into the specific poetic laws at work in the poetry of Nelly Sachs.
Outcomes of arthroscopic "Remplissage": capsulotenodesis of the engaging large Hill-Sachs lesion
Directory of Open Access Journals (Sweden)
Mayo Lee
2011-06-01
Full Text Available Abstract Background A Hill-Sachs lesion of the humeral head after a shoulder dislocation is clinically insignificant in most cases. However, a sizable defect will engage with the anterior rim of the glenoid and cause instability even after anterior glenoid reconstruction. The purpose of this study was to evaluate the outcome of arthroscopic capsulotenodesis of the posterior capsule and infraspinatus tendon ("remplissage" to seal a large engaging Hill-Sachs lesion in an unstable shoulder. Methods This was a prospective follow-up study of patients who underwent arthroscopic surgery for recurrent shoulder instability with a large engaging Hill-Sachs lesion from 2007 to 2009. The clinical results were measured preoperatively and postoperatively with the Simple Shoulder test (SST and the Rowe score for instability. Results Eleven patients met the inclusion criteria of this study. The mean follow-up time was 30 months (range 24 to 35 months. At the last follow-up, significant improvement was observed in both scores with no recurrent dislocations. The mean SST improved from 6.6 to 11 (p Conclusions Arthroscopic remplissage for shoulder instability is an effective soft tissue technique to seal a large engaging Hill-Sachs lesion with respect to recurrence rate, range of motion and shoulder function.
78 FR 24447 - Goldman Sachs Trust, et al.; Notice of Application
2013-04-25
... Sachs, an investment adviser registered under the Advisers Act and a broker-dealer registered under the..., to the extent consistent with its investment objectives, policies, strategies and limitations, in..., or broker or dealer if registered under the Securities Exchange Act of 1934 (``Exchange Act''),...
Daza, Maicol A Ochoa
2011-01-01
We introduce and develop the theory of metric sheaves. A metric sheaf $\\A$ is defined on a topological space $X$ such that each fiber is a metric model. We describe the construction of the generic model as the quotient space of the sheaf through an appropriate filter. Semantics in this model is completely controlled and understood by the forcing rules in the sheaf.
Sachês antimicrobianos em pós-colheita de manga
Directory of Open Access Journals (Sweden)
Eber Antonio Alves Medeiros
2011-10-01
Full Text Available Objetivou-se com este trabalho desenvolver sachês incorporados com óleos essenciais avaliando as propriedades físico-químicas e microbiológicas de mangas armazenadas em saco de papel contendo estes sachês em seu interior. Os óleos essenciais de orégano (Origanum vulgaris e capim-limão (Cymbopogon citratus foram incorporados em saches, e sua atividade antimicrobiana foi testada nos fungos Colletotrichum gloeosporides, Lasiodiplodia theobromae, Xanthomonas campestris pv. mangiferae indica, Alternaria alternata. Frutos de manga 'Tommy Atkins' foram acondicionados individualmente em sacos de papel contendo em seu interior um sachê antimicrobiano e mantidos a 25 °C ± 2 °C e UR 80% ± 5% por nove dias. Os parâmetros cor da epiderme, firmeza de polpa, sólidos solúveis, acidez titulável e pH sofreram pouca influência dos óleos essenciais de orégano e capim limão, indicando que a presença do óleo essencial não altera as características físico-químicas da polpa de manga. Os sachês ativos incorporados com óleos essenciais de orégano e capim limão apresentaram controle no crescimento dos microrganismos testados, sendo o capim-limão mais eficiente, reduzindo em aproximadamente 2 ciclos Log a contagem de mesófilos aeróbios e fungos filamentosos e leveduras em relação ao tratamento controle empregado.
Does the Arthroscopic Latarjet Procedure Effectively Correct "Off-Track" Hill-Sachs Lesions?
Plath, Johannes E; Henderson, Daniel J H; Coquay, Julien; Dück, Klaus; Haeni, David; Lafosse, Laurent
2017-09-01
The glenoid track concept describes the dynamic interaction of bipolar bone loss in anterior glenohumeral instability. Initial studies have successfully demonstrated this concept's application in clinical populations. In clinical practice, the Latarjet procedure is commonly the preferred treatment in addressing "off-track" Hill-Sachs lesions. The effectiveness of this procedure in restoring such lesions to an "on-track" state, however, has not yet been evaluated or described in the literature. The Latarjet procedure would transform "off-track" Hill-Sachs lesions to "on-track" lesions. Lesions would remain "on-track" during follow-up, despite glenoid remodeling. Case series; Level of evidence, 4. Patients with "off-track" Hill-Sachs lesions treated with the arthroscopic Latarjet procedure between March 2013 and May 2014 were included. Glenoid track and coracoid graft contact surface area measurements using 3-dimensional computed tomography (3D-CT) were performed preoperatively and at 6-week, 6-month, and at least 12-month (final) follow-up. The mean final follow-up was 23 months. The glenoid diameter, as a percentage of the native glenoid, was also calculated from this imaging. Twenty-six patients met the inclusion criteria. 3D-CT scans were available for all patients preoperatively and postoperatively, with 21 patients (81%) undergoing 6-month follow-up CT and 19 patients (73%) undergoing final follow-up CT. Hill-Sachs lesions remained "on-track" at all follow-up time points. The mean glenoid diameter changed significantly from 84.6% preoperatively to 122.8% at 6 weeks ( P Latarjet procedure provides an effective treatment for "off-track" engaging Hill-Sachs lesions, despite an evident glenoid remodeling process. At a mean of 23 months postoperatively, a mean persisting enlargement of the glenoid arc of 14% beyond native dimensions remained, avoiding a recurrent "off-track" lesion in 32% of patients, which would otherwise have occurred with complete remodeling.
Directory of Open Access Journals (Sweden)
Roberto Rozenberg
Full Text Available CONTEXT: Tay-Sachs disease is an autosomal recessive disease characterized by progressive neurologic degeneration, fatal in early childhood. In the Ashkenazi Jewish population the disease incidence is about 1 in every 3,500 newborns and the carrier frequency is 1 in every 29 individuals. Carrier screening programs for Tay-Sachs disease have reduced disease incidence by 90% in high-risk populations in several countries. The Brazilian Jewish population is estimated at 90,000 individuals. Currently, there is no screening program for Tay-Sachs disease in this population. OBJECTIVE: To evaluate the importance of a Tay-Sachs disease carrier screening program in the Brazilian Jewish population by determining the frequency of heterozygotes and the acceptance of the program by the community. SETTING: Laboratory of Molecular Genetics - Institute of Biosciences - Universidade de São Paulo. PARTICIPANTS: 581 senior students from selected Jewish high schools. PROCEDURE: Molecular analysis of Tay-Sachs disease causing mutations by PCR amplification of genomic DNA, followed by restriction enzyme digestion. RESULTS: Among 581 students that attended educational classes, 404 (70% elected to be tested for Tay-Sachs disease mutations. Of these, approximately 65% were of Ashkenazi Jewish origin. Eight carriers were detected corresponding to a carrier frequency of 1 in every 33 individuals in the Ashkenazi Jewish fraction of the sample. CONCLUSION: The frequency of Tay-Sachs disease carriers among the Ashkenazi Jewish population of Brazil is similar to that of other countries where carrier screening programs have led to a significant decrease in disease incidence. Therefore, it is justifiable to implement a Tay-Sachs disease carrier screening program for the Brazilian Jewish population.
Horst, K; Von Harten, R; Weber, C; Andruszkow, H; Pfeifer, R; Dienstknecht, T; Pape, H C
2014-02-01
Bankart and Hill-Sachs lesions are often associated with anterior shoulder dislocation. The MRI technique is sensitive in diagnosing both injuries. The aim of this study was to investigate Bankart and Hill-Sachs lesions with MRI to determine the correlation in occurrence and defect sizes of these lesions. Between 2006 and 2013, 446 patients were diagnosed with an anterior shoulder dislocation and 105 of these patients were eligible for inclusion in the study. All patients were examined using MRI. Bankart lesions were classified as cartilaginous or bony lesions. Hill-Sachs lesions were graded I-III using a modified Calandra classification. The co-occurrence of injuries was high [odds ratio (OR) = 11.47; 95% confidence interval (CI) = 3.60-36.52; p Bankart lesion and the grade of a Hill-Sachs lesion was found (ρ = 0.34; 95% CI = 0.16-0.49; p Bankart lesions co-occurred more often with large Hill-Sachs lesions (O = 1.24; 95% CI = 1.02-1.52; p = 0.033). If either lesion is diagnosed, the patient is 11 times more likely to have suffered the associated injury. The size of a Hill-Sachs lesion determines the co-occurrence of cartilaginous or bony Bankart lesions. Age plays a role in determining the type of Bankart lesion as well as the co-occurrence of Bankart and Hill-Sachs lesions. This study is the first to demonstrate the use of high-quality MRI in a reasonably large sample of patients, a positive correlation of Bankart and Hill-Sachs lesions in anterior shoulder dislocations and an association between the defect sizes.
Von Harten, R; Weber, C; Andruszkow, H; Pfeifer, R; Dienstknecht, T; Pape, H C
2014-01-01
Objective: Bankart and Hill–Sachs lesions are often associated with anterior shoulder dislocation. The MRI technique is sensitive in diagnosing both injuries. The aim of this study was to investigate Bankart and Hill–Sachs lesions with MRI to determine the correlation in occurrence and defect sizes of these lesions. Methods: Between 2006 and 2013, 446 patients were diagnosed with an anterior shoulder dislocation and 105 of these patients were eligible for inclusion in the study. All patients were examined using MRI. Bankart lesions were classified as cartilaginous or bony lesions. Hill–Sachs lesions were graded I–III using a modified Calandra classification. Results: The co-occurrence of injuries was high [odds ratio (OR) = 11.47; 95% confidence interval (CI) = 3.60–36.52; p Bankart lesion and the grade of a Hill–Sachs lesion was found (ρ = 0.34; 95% CI = 0.16–0.49; p Bankart lesions co-occurred more often with large Hill–Sachs lesions (OR = 1.24; 95% CI = 1.02–1.52; p = 0.033). Conclusion: If either lesion is diagnosed, the patient is 11 times more likely to have suffered the associated injury. The size of a Hill–Sachs lesion determines the co-occurrence of cartilaginous or bony Bankart lesions. Age plays a role in determining the type of Bankart lesion as well as the co-occurrence of Bankart and Hill–Sachs lesions. Advances in knowledge: This study is the first to demonstrate the use of high-quality MRI in a reasonably large sample of patients, a positive correlation of Bankart and Hill–Sachs lesions in anterior shoulder dislocations and an association between the defect sizes. PMID:24452107
Hussein, Norita; Weng, Stephen F; Kai, Joe; Kleijnen, Jos; Qureshi, Nadeem
2015-08-12
Globally, about five per cent of children are born with congenital or genetic disorders. The most common autosomal recessive conditions are thalassaemia, sickle cell disease, cystic fibrosis and Tay-Sachs disease, with higher carrier rates in specific patient populations. Identifying and counselling couples at genetic risk of the conditions before pregnancy enables them to make fully informed reproductive decisions, with some of these choices not being available if genetic counselling is only offered in an antenatal setting. To assess the effectiveness of systematic preconception genetic risk assessment to improve reproductive outcomes in women and their partners who are identified as carriers of thalassaemia, sickle cell disease, cystic fibrosis and Tay-Sachs disease in healthcare settings when compared to usual care. We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group's Trials Registers. In addition, we searched for all relevant trials from 1970 (or the date at which the database was first available if after 1970) to date using electronic databases (MEDLINE, Embase, CINAHL, PsycINFO), clinical trial databases (National Institutes of Health, Clinical Trials Search portal of the World Health Organization, metaRegister of controlled clinical trials), and hand searching of key journals and conference abstract books from 1998 to date (European Journal of Human Genetics, Genetics in Medicine, Journal of Community Genetics). We also searched the reference lists of relevant articles, reviews and guidelines and also contacted subject experts in the field to request any unpublished or other published trials.Date of latest search of the registers: 25 June 2015.Date of latest search of all other sources: 10 December 2014. Any randomised or quasi-randomised control trials (published or unpublished) comparing reproductive outcomes of systematic preconception genetic risk assessment for thalassaemia, sickle cell disease, cystic fibrosis and Tay-Sachs disease
Chistyakov, Vyacheslav
2015-01-01
Aimed toward researchers and graduate students familiar with elements of functional analysis, linear algebra, and general topology; this book contains a general study of modulars, modular spaces, and metric modular spaces. Modulars may be thought of as generalized velocity fields and serve two important purposes: generate metric spaces in a unified manner and provide a weaker convergence, the modular convergence, whose topology is non-metrizable in general. Metric modular spaces are extensions of metric spaces, metric linear spaces, and classical modular linear spaces. The topics covered include the classification of modulars, metrizability of modular spaces, modular transforms and duality between modular spaces, metric and modular topologies. Applications illustrated in this book include: the description of superposition operators acting in modular spaces, the existence of regular selections of set-valued mappings, new interpretations of spaces of Lipschitzian and absolutely continuous mappings, the existe...
Metric diffusion along foliations
Walczak, Szymon M
2017-01-01
Up-to-date research in metric diffusion along compact foliations is presented in this book. Beginning with fundamentals from the optimal transportation theory and the theory of foliations; this book moves on to cover Wasserstein distance, Kantorovich Duality Theorem, and the metrization of the weak topology by the Wasserstein distance. Metric diffusion is defined, the topology of the metric space is studied and the limits of diffused metrics along compact foliations are discussed. Essentials on foliations, holonomy, heat diffusion, and compact foliations are detailed and vital technical lemmas are proved to aide understanding. Graduate students and researchers in geometry, topology and dynamics of foliations and laminations will find this supplement useful as it presents facts about the metric diffusion along non-compact foliation and provides a full description of the limit for metrics diffused along foliation with at least one compact leaf on the two dimensions.
Enterprise Sustainment Metrics
The Air Force sustainment enterprise does not have metrics that . . . adequately measure key sustainment parameters, according to the 2011 National...standardized and do not contribute to the overall assessment of the sustainment enterprise . This paper explores the development of a single metric...is not feasible. To answer the question does the sustainment enterprise provide cost-effective readiness for a weapon system, a suite of metrics is
-Metric Space: A Generalization
Directory of Open Access Journals (Sweden)
Farshid Khojasteh
2013-01-01
Full Text Available We introduce the notion of -metric as a generalization of a metric by replacing the triangle inequality with a more generalized inequality. We investigate the topology of the spaces induced by a -metric and present some essential properties of it. Further, we give characterization of well-known fixed point theorems, such as the Banach and Caristi types in the context of such spaces.
Prognostic Performance Metrics
National Aeronautics and Space Administration — This chapter presents several performance metrics for offline evaluation of prognostics algorithms. A brief overview of different methods employed for performance...
Topics in Metric Approximation
Leeb, William Edward
This thesis develops effective approximations of certain metrics that occur frequently in pure and applied mathematics. We show that distances that often arise in applications, such as the Earth Mover's Distance between two probability measures, can be approximated by easily computed formulas for a wide variety of ground distances. We develop simple and easily computed characterizations both of norms measuring a function's regularity -- such as the Lipschitz norm -- and of their duals. We are particularly concerned with the tensor product of metric spaces, where the natural notion of regularity is not the Lipschitz condition but the mixed Lipschitz condition. A theme that runs throughout this thesis is that snowflake metrics (metrics raised to a power less than 1) are often better-behaved than ordinary metrics. For example, we show that snowflake metrics on finite spaces can be approximated by the average of tree metrics with a distortion bounded by intrinsic geometric characteristics of the space and not the number of points. Many of the metrics for which we characterize the Lipschitz space and its dual are snowflake metrics. We also present applications of the characterization of certain regularity norms to the problem of recovering a matrix that has been corrupted by noise. We are able to achieve an optimal rate of recovery for certain families of matrices by exploiting the relationship between mixed-variable regularity conditions and the decay of a function's coefficients in a certain orthonormal basis.
Directory of Open Access Journals (Sweden)
Nakasho Kazuhisa
2016-09-01
Full Text Available In this article, we mainly formalize in Mizar [2] the equivalence among a few compactness definitions of metric spaces, norm spaces, and the real line. In the first section, we formalized general topological properties of metric spaces. We discussed openness and closedness of subsets in metric spaces in terms of convergence of element sequences. In the second section, we firstly formalize the definition of sequentially compact, and then discuss the equivalence of compactness, countable compactness, sequential compactness, and totally boundedness with completeness in metric spaces.
Surveillance Metrics Sensitivity Study
Energy Technology Data Exchange (ETDEWEB)
Bierbaum, R; Hamada, M; Robertson, A
2011-11-01
In September of 2009, a Tri-Lab team was formed to develop a set of metrics relating to the NNSA nuclear weapon surveillance program. The purpose of the metrics was to develop a more quantitative and/or qualitative metric(s) describing the results of realized or non-realized surveillance activities on our confidence in reporting reliability and assessing the stockpile. As a part of this effort, a statistical sub-team investigated various techniques and developed a complementary set of statistical metrics that could serve as a foundation for characterizing aspects of meeting the surveillance program objectives. The metrics are a combination of tolerance limit calculations and power calculations, intending to answer level-of-confidence type questions with respect to the ability to detect certain undesirable behaviors (catastrophic defects, margin insufficiency defects, and deviations from a model). Note that the metrics are not intended to gauge product performance but instead the adequacy of surveillance. This report gives a short description of four metrics types that were explored and the results of a sensitivity study conducted to investigate their behavior for various inputs. The results of the sensitivity study can be used to set the risk parameters that specify the level of stockpile problem that the surveillance program should be addressing.
Cooper, Gloria S., Ed.; Magisos, Joel H., Ed.
Designed to meet the job-related metric measurement needs of students interested in transportation, this instructional package is one of five for the marketing and distribution cluster, part of a set of 55 packages for metric instruction in different occupations. The package is intended for students who already know the occupational terminology,…
Metrics for Food Distribution.
Cooper, Gloria S., Ed.; Magisos, Joel H., Ed.
Designed to meet the job-related metric measurement needs of students interested in food distribution, this instructional package is one of five for the marketing and distribution cluster, part of a set of 55 packages for metric instruction in different occupations. The package is intended for students who already know the occupational…
Metric Education Evaluation Package.
Kansky, Bob; And Others
This document was developed out of a need for a complete, carefully designed set of evaluation instruments and procedures that might be applied in metric inservice programs across the nation. Components of this package were prepared in such a way as to permit local adaptation to the evaluation of a broad spectrum of metric education activities.…
Computational visual distinctness metric
Martínez-Baena, J.; Toet, A.; Fdez-Vidal, X.R.; Garrido, A.; Rodríguez-Sánchez, R.
1998-01-01
A new computational visual distinctness metric based on principles of the early human visual system is presented. The metric is applied to quantify (1) the visual distinctness of targets in complex natural scenes and (2) the perceptual differences between compressed and uncompressed images. The new
Institute of Scientific and Technical Information of China (English)
ZHAOZhen-gang
2005-01-01
We have constructed the positive definite metric matrixes for the bounded domains of Rn and proved an inequality which is about the Jacobi matrix of a harmonic mapping on a bounded domain of Rn and the metric matrix of the same bounded domain.
Privacy Metrics and Boundaries
L-F. Pau (Louis-François)
2005-01-01
textabstractThis paper aims at defining a set of privacy metrics (quantitative and qualitative) in the case of the relation between a privacy protector ,and an information gatherer .The aims with such metrics are: -to allow to assess and compare different user scenarios and their differences; for ex
Nakamura, Sadao; Saito, Yoshiaki; Ishiyama, Akihiko; Sugai, Kenji; Iso, Takashi; Inagaki, Masumi; Sasaki, Masayuki
2015-01-01
To clarify the evolution of an augmented startle reflex in Tay-Sachs disease and compare the temporal relationship between this reflex and brainstem evoked potentials. Clinical and electrophysiological data from 3 patients with Tay-Sachs disease were retrospectively collected. The augmented startle reflex appeared between the age of 3 and 17 months and disappeared between the age of 4 and 6 years. Analysis of brainstem auditory evoked potentials revealed that poor segregation of peak I, but not peak III, coincided with the disappearance of the augmented startle reflex. A blink reflex with markedly high amplitude was observed in a patient with an augmented startle reflex. The correlation between the augmented startle reflex and the preservation of peak I but not peak III supports the theory that the superior olivary nucleus is dispensable for this reflex. The blink reflex with high amplitudes may represent augmented excitability of reticular formation at the pontine tegmentum in Tay-Sachs disease, where the pattern generators for the augmented startle and blink reflexes may functionally overlap. Copyright © 2014 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.
Lyso-GM2 ganglioside: a possible biomarker of Tay-Sachs disease and Sandhoff disease.
Directory of Open Access Journals (Sweden)
Takashi Kodama
Full Text Available To find a new biomarker of Tay-Sachs disease and Sandhoff disease. The lyso-GM2 ganglioside (lyso-GM2 levels in the brain and plasma in Sandhoff mice were measured by means of high performance liquid chromatography and the effect of a modified hexosaminidase (Hex B exhibiting Hex A-like activity was examined. Then, the lyso-GM2 concentrations in human plasma samples were determined. The lyso-GM2 levels in the brain and plasma in Sandhoff mice were apparently increased compared with those in wild-type mice, and they decreased on intracerebroventricular administration of the modified Hex B. The lyso-GM2 levels in plasma of patients with Tay-Sachs disease and Sandhoff disease were increased, and the increase in lyso-GM2 was associated with a decrease in Hex A activity. Lyso-GM2 is expected to be a potential biomarker of Tay-Sachs disease and Sandhoff disease.
Holographic Spherically Symmetric Metrics
Petri, Michael
The holographic principle (HP) conjectures, that the maximum number of degrees of freedom of any realistic physical system is proportional to the system's boundary area. The HP has its roots in the study of black holes. It has recently been applied to cosmological solutions. In this article we apply the HP to spherically symmetric static space-times. We find that any regular spherically symmetric object saturating the HP is subject to tight constraints on the (interior) metric, energy-density, temperature and entropy-density. Whenever gravity can be described by a metric theory, gravity is macroscopically scale invariant and the laws of thermodynamics hold locally and globally, the (interior) metric of a regular holographic object is uniquely determined up to a constant factor and the interior matter-state must follow well defined scaling relations. When the metric theory of gravity is general relativity, the interior matter has an overall string equation of state (EOS) and a unique total energy-density. Thus the holographic metric derived in this article can serve as simple interior 4D realization of Mathur's string fuzzball proposal. Some properties of the holographic metric and its possible experimental verification are discussed. The geodesics of the holographic metric describe an isotropically expanding (or contracting) universe with a nearly homogeneous matter-distribution within the local Hubble volume. Due to the overall string EOS the active gravitational mass-density is zero, resulting in a coasting expansion with Ht = 1, which is compatible with the recent GRB-data.
Blecher, David P
2012-01-01
The present paper is a sequel to our paper "Metric characterization of isometries and of unital operator spaces and systems". We characterize certain common objects in the theory of operator spaces (unitaries, unital operator spaces, operator systems, operator algebras, and so on), in terms which are purely linear-metric, by which we mean that they only use the vector space structure of the space and its matrix norms. In the last part we give some characterizations of operator algebras (which are not linear-metric in our strict sense described in the paper).
Characterization of Multiplicative Metric Completeness
Directory of Open Access Journals (Sweden)
Badshshah e Romer
2016-03-01
Full Text Available We established fixed point theorems in multiplicative metric spaces. The obtained results generalize Banach contraction principle in multiplicative metric spaces and also characterize completeness of the underlying multiplicative metric space.
Webb, Ted
1976-01-01
Describes the program to convert to the metric system all of General Motors Corporation products. Steps include establishing policy regarding employee-owned tools, setting up training plans, and making arrangements with suppliers. (MF)
Schweizer, B
2005-01-01
Topics include special classes of probabilistic metric spaces, topologies, and several related structures, such as probabilistic normed and inner-product spaces. 1983 edition, updated with 3 new appendixes. Includes 17 illustrations.
Carver, Gary P.
1994-05-01
The federal agencies are working with industry to ease adoption of the metric system. The goal is to help U.S. industry compete more successfully in the global marketplace, increase exports, and create new jobs. The strategy is to use federal procurement, financial assistance, and other business-related activities to encourage voluntary conversion. Based upon the positive experiences of firms and industries that have converted, federal agencies have concluded that metric use will yield long-term benefits that are beyond any one-time costs or inconveniences. It may be time for additional steps to move the Nation out of its dual-system comfort zone and continue to progress toward metrication. This report includes 'Metric Highlights in U.S. History'.
Mass Customization Measurements Metrics
DEFF Research Database (Denmark)
Nielsen, Kjeld; Brunø, Thomas Ditlev; Jørgensen, Kaj Asbjørn
2014-01-01
A recent survey has indicated that 17 % of companies have ceased mass customizing less than 1 year after initiating the effort. This paper presents measurement for a company’s mass customization performance, utilizing metrics within the three fundamental capabilities: robust process design, choice...... navigation, and solution space development. A mass customizer when assessing performance with these metrics can identify within which areas improvement would increase competitiveness the most and enable more efficient transition to mass customization....
Balvín, Radek
2013-01-01
With growing amount of data produced by users on social media the need of extraction of relevant data for marketing, research and other uses grows as well. The bachelor thesis named "Social media metrics" presents the issues of monitoring, measurement and metrics of social media. In the research part it also maps and captures the present Czech practice in measurement and monitoring of social media. I also rate the use of social media monitoring tools and usual methods of social media measurem...
Expanding the spectrum of HEXA mutations in Indian patients with Tay–Sachs disease
Directory of Open Access Journals (Sweden)
Jayesh Sheth
2014-01-01
Full Text Available Tay–Sachs disease is an autosomal recessive neurodegenerative disorder occurring due to impaired activity of β-hexosaminidase-A (EC 3.2.1.52, resulting from the mutation in HEXA gene. Very little is known about the molecular pathology of TSD in Indian children except for a few mutations identified by us. The present study is aimed to determine additional mutations leading to Tay–Sachs disease in nine patients confirmed by the deficiency of β-hexosaminidase-A (C (D175A and c.805G>C (p.G269R in one case; and one small 1 bp deletion c.426delT (p.F142LfsX57 and one splice site mutation c.459+4A>C in the other two cases respectively. None of these mutations were detected in 100 chromosomes from healthy individuals of the same ethnic group. Three previously reported missense mutations, (i c.532C>T (p.R178C, (ii c.964G>T (p.D322Y, and (iii c.1385A>T (p.E462V; two nonsense mutations (i c.709C>T (p.Q237X and (ii c.1528C>T (p.R510X, one 4 bp insertion c.1277_1278insTATC (p.Y427IfsX5 and one splice site mutation c.459+5G>A were also identified in six cases. We observe from this study that novel mutations are more frequently observed in Indian patients with Tay–Sachs disease with clustering of ~73% of disease causing mutations in exons 5 to 12. This database can be used for a carrier rate screening in the larger population of the country.
Expanding the spectrum of HEXA mutations in Indian patients with Tay-Sachs disease.
Sheth, Jayesh; Mistri, Mehul; Datar, Chaitanya; Kalane, Umesh; Patil, Shekhar; Kamate, Mahesh; Shah, Harshuti; Nampoothiri, Sheela; Gupta, Sarita; Sheth, Frenny
2014-01-01
Tay-Sachs disease is an autosomal recessive neurodegenerative disorder occurring due to impaired activity of β-hexosaminidase-A (EC 3.2.1.52), resulting from the mutation in HEXA gene. Very little is known about the molecular pathology of TSD in Indian children except for a few mutations identified by us. The present study is aimed to determine additional mutations leading to Tay-Sachs disease in nine patients confirmed by the deficiency of β-hexosaminidase-A (C (D175A) and c.805G>C (p.G269R) in one case; and one small 1 bp deletion c.426delT (p.F142LfsX57) and one splice site mutation c.459+4A>C in the other two cases respectively. None of these mutations were detected in 100 chromosomes from healthy individuals of the same ethnic group. Three previously reported missense mutations, (i) c.532C>T (p.R178C), (ii) c.964G>T (p.D322Y), and (iii) c.1385A>T (p.E462V); two nonsense mutations (i) c.709C>T (p.Q237X) and (ii) c.1528C>T (p.R510X), one 4 bp insertion c.1277_1278insTATC (p.Y427IfsX5) and one splice site mutation c.459+5G>A were also identified in six cases. We observe from this study that novel mutations are more frequently observed in Indian patients with Tay-Sachs disease with clustering of ~ 73% of disease causing mutations in exons 5 to 12. This database can be used for a carrier rate screening in the larger population of the country.
Cho, Nam Su; Yoo, Jae Hyun; Rhee, Yong Girl
2016-12-01
This study compared the clinical outcomes of arthroscopic remplissage with Bankart repair and Latarjet operation in patients with a large engaging Hill-Sachs lesion. Thirty-seven shoulders subjected to arthroscopic remplissage with a Bankart repair (group A) and 35 shoulders subjected to a Latarjet operation (group B), for a large engaging Hill-Sachs lesion without significant glenoid bone loss, were retrospectively evaluated. Each group was followed up for a mean more than 2-year period. At the last follow-up, postoperative pain, shoulder mobility, muscle strength, Rowe score, and UCLA score revealed no significant difference between the two groups. The postoperative mean deficit in external rotation at the side (ERs) was 8° ± 23° in group A (P = 0.044). In group B, the mean deficits in ERs, external rotation at 90° of abduction, and internal rotation to the posterior were 10° ± 20°, 7° ± 16°, and 1.9° ± 4°, respectively (P = 0.004, 0.022, and 0.009, respectively). The recurrence rate was 5.4 % (two shoulders) in group A and 5.7 % (two shoulders) in group B (n.s.). The overall complication rate was significantly higher in group B (14.3 %) than in group A (0 %) (P = 0.017). For recurrent anterior shoulder instability with a large engaging Hill-Sachs lesion, both arthroscopic remplissage with Bankart repair and the Latarjet procedure were safe and reliable techniques with a low recurrence rate. However, the Latarjet group had a significantly higher postoperative complication rate than the remplissage group. Case-control study, Level III.
Bonnevialle, Nicolas; Azoulay, Vadim; Faraud, Amélie; Elia, Fanny; Swider, Pascal; Mansat, Pierre
2017-05-11
The aim of this study was to evaluate mid-term outcomes of Bankart repair with Hill-Sachs remplissage (BHSR) and to highlight prognostic factors of failure. Thirty-four patients operated on for anterior shoulder instability with BHSR were enrolled in a prospective non-randomised study. Clinical and radiographic evaluation was performed at 1.5, three, six months and yearly thereafter. Outcome measures included Rowe and Walch-Duplay score. At mean follow-up of 35 months (24-63), the Rowe and Walch-Duplay scores reached respectively 92.7 and 88.2 points. The mean deficit in external rotation was 6° in ER1 and 1° in ER2 (p = 0.4, p = 0.9 respectively). Five patients (14.7%) had a recurrence of instability and three others had a persistent anterior apprehension. In the failure group, the Hill-Sachs lesion was deeper (26% vs 19% of the humeral diameter; p = 0.04) and range of motion at 1.5 months postoperatively was greater. Age at surgery, pre-operative instability severity index score (ISIS), hyperlaxity, type and level of sport, amount of glenoid bone loss had no correlation with failure rate. The rate of failure at mid-term follow-up of BHSR was higher than commonly reported. The premature recovery of range of motion seems to be a clinical sign of failure at follow-up. Moreover, in case of deep Hill-Sachs lesion (>20%) an alternative procedure should be considered. Level IV.
Einstein Metrics on Complex Surfaces
Lebrun, C
1995-01-01
We consider compact complex surfaces with Hermitian metrics which are Einstein but not Kaehler. It is shown that the manifold must be CP2 blown up at 1,2, or 3 points, and the isometry group of the metric must contain a 2-torus. Thus the Page metric on CP2#(-CP2) is almost the only metric of this type.
lnduced Pluripotent Stem cells disease modeling: approaching Gaucher and Tay Sachs
Lorenzo Vivas, Erica
2013-01-01
Las iPS (células pluripotentes inducidas) se han revelado como potentes herramientas en la creación de modelos de enfermedades humanas para su estudio y el testeo de potenciales drogas. En este marco hemos desarrollado un proyecto para derivar iPS de fibroblastos de pacientes de Gaucher y Tay Sachs, ambas enfermedades monogénicas recesivas. La enfermedad de Gaucher se caracteriza por la deficiencia de la glucocerebrosidasa (GBA), lo que conlleva la acumulación de su substrato, la glucosi...
Cross-correlation between thermal Sunyaev-Zeldovich effect and the integrated Sachs-Wolfe effect
Creque-Sarbinowski, Cyril; Kamionkowski, Marc
2016-01-01
Large-angle fluctuations in the cosmic microwave background (CMB) temperature induced by the integrated Sachs-Wolfe (ISW) effect and Compton-y distortions from the thermal Sunyaev-Zeldovich (tSZ) effect are both due to line-of-sight density perturbations. Here we calculate the cross-correlation between these two signals. Measurement of this cross-correlation can be used to test the redshift distribution of the tSZ distortion. We also evaluate the detectability of a yT cross-correlation from exotic early-Universe sources in the presence of this late-time effect.
Degen, Ryan M; Giles, Joshua W; Johnson, James A; Athwal, George S
2014-08-01
Recurrent shoulder instability is commonly associated with Hill-Sachs defects. These defects may engage the glenoid rim, contributing to glenohumeral dislocation. Two treatment options to manage engaging Hill-Sachs defects are the remplissage procedure, which fills the defect with soft tissue, and the Latarjet procedure, which increases glenoid arc length. Little evidence exists to support one over the other. We performed a biomechanical comparison of the remplissage procedure to the traditional Latarjet coracoid transfer for management of engaging Hill-Sachs defects in terms of joint stiffness (resistance to anterior translation), ROM, and frequency of dislocation. Eight cadaveric specimens were tested on a shoulder instability simulator. Testing was performed with a 25% Hill-Sachs defect with an intact glenoid and after remplissage and Latarjet procedures. Joint stiffness, internal-external rotation ROM, and frequency of dislocation were assessed. Additionally, horizontal extension ROM was measured in composite glenohumeral abduction. After remplissage, stiffness increased in adduction with neutral rotation (12.7 ± 3.7 N/mm) relative to the Hill-Sachs defect state (8.7 ± 3.3 N/mm; p = 0.016). The Latarjet procedure did not affect joint stiffness (p = 1.0). Internal-external rotation ROM was reduced in abduction after the Latarjet procedure (49° ± 14°) compared with the Hill-Sachs defect state (69° ± 17°) (p = 0.009). Horizontal extension was reduced after remplissage (16° ± 12°) relative to the Hill-Sachs defect state (34° ± 8°) (p = 0.038). With the numbers available, there was no difference between the procedures in terms of the frequency of dislocation after reconstruction: 84% of specimens (27 of 32 testing scenarios) stabilized after remplissage, while 94% of specimens (30 of 32 testing scenarios) stabilized after the Latarjet procedure. Both procedures proved effective in reducing the frequency of dislocation in a 25% Hill-Sachs defect model
Energy Technology Data Exchange (ETDEWEB)
Frye, Jason Neal; Veitch, Cynthia K.; Mateski, Mark Elliot; Michalski, John T.; Harris, James Mark; Trevino, Cassandra M.; Maruoka, Scott
2012-03-01
Threats are generally much easier to list than to describe, and much easier to describe than to measure. As a result, many organizations list threats. Fewer describe them in useful terms, and still fewer measure them in meaningful ways. This is particularly true in the dynamic and nebulous domain of cyber threats - a domain that tends to resist easy measurement and, in some cases, appears to defy any measurement. We believe the problem is tractable. In this report we describe threat metrics and models for characterizing threats consistently and unambiguously. The purpose of this report is to support the Operational Threat Assessment (OTA) phase of risk and vulnerability assessment. To this end, we focus on the task of characterizing cyber threats using consistent threat metrics and models. In particular, we address threat metrics and models for describing malicious cyber threats to US FCEB agencies and systems.
Isospectral Metrics on Projective Spaces
Rueckriemen, Ralf
2011-01-01
We construct isospectral non isometric metrics on real and complex projective space. We recall the construction using isometric torus actions by Carolyn Gordon in chapter 2. In chapter 3 we will recall some facts about complex projective space. In chapter 4 we build the isospectral metrics. Chapter 5 is devoted to the non isometry proof of the metrics built in chapter 4. In chapter 6 isospectral metrics on real projective space are derived from metrics on the sphere.
Vortices as degenerate metrics
Baptista, J M
2012-01-01
We note that the Bogomolny equation for abelian vortices is precisely the condition for invariance of the Hermitian-Einstein equation under a degenerate conformal transformation. This leads to a natural interpretation of vortices as degenerate hermitian metrics that satisfy a certain curvature equation. Using this viewpoint, we rephrase standard results about vortices and make some new observations. We note the existence of a conceptually simple, non-linear rule for superposing vortex solutions, and we describe the natural behaviour of the L^2-metric on the moduli space upon certain restrictions.
Uniformly Convex Metric Spaces
Kell Martin
2014-01-01
In this paper the theory of uniformly convex metric spaces is developed. These spaces exhibit a generalized convexity of the metric from a fixed point. Using a (nearly) uniform convexity property a simple proof of reflexivity is presented and a weak topology of such spaces is analyzed. This topology called co-convex topology agrees with the usualy weak topology in Banach spaces. An example of a $CAT(0)$-spaces with weak topology which is not Hausdorff is given. This answers questions raised b...
Sarkar, Sarben
2010-01-01
The role of Finsler-like metrics in situations where Lorentz symmetry breaking and also CPT violation are discussed. Various physical instances of such metrics both in quantum gravity and analogue systems are discussed. Both differences and similarities between the cases will be emphasised. In particular the medium of D-particles that arise in string theory will be examined. In this case the breaking of Lorentz invariance, at the level of quantum fluctuations, together with concomitant CPT in certain situations will be analysed. In particular it will be shown correlations for neutral meson pairs will be modified and a new contribution to baryogenesis will appear.
AAV gene therapy in a sheep model of Tay-Sachs disease.
Gray-Edwards, Heather; Randle, Ashley N; Maitland, Stacy; Benatti, Hector; Hubbard, Spencer; Canning, Peter; Vogel, Matthew; Brunson, Brandon; Hwang, Misako; Ellis, Lauren; Bradbury, Allison M; Gentry, Atoska; Taylor, Amanda; Wooldridge, Anne; Wilhite, Dewey; Winter, Randoplh; Whitlock, Brain; Johnson, Jacob A; Holland, Merrilee; Salibi, Nouha; Beyers, Ronald; Sartin, James; Denney, Thomas; Cox, Nancy R; Sena-Esteves, Miguel; Martin, Douglas R
2017-09-19
Tay-Sachs disease (TSD) is a fatal neurodegenerative disorder caused by a deficiency of the enzyme hexosaminidase A (HexA). Tay-Sachs disease also occurs in sheep, the only experimental model of TSD that has clinical signs of disease. The natural history of sheep TSD was characterized using serial neurological evaluations, 7 tesla MRI, echocardiograms, electrodiagnostics and cerebrospinal fluid (CSF) biomarkers. Intracranial gene therapy was also tested using AAVrh8 monocistronic vectors encoding the α subunit of Hex (TSD α) or a mixture of two vectors encoding both the α and β subunits separately (TSD α+β) injected at high (1.3 x1013vg) or low (4.2x1012vg) dose. Delay of symptom onset and/or reduction of acquired symptoms were noted in all AAV treated sheep. Post-mortem evaluation showed superior HexA and vector genome distribution in the brain of TSD α+β sheep compared to TSD α sheep, but spinal cord distribution was low in all groups. Isozyme analysis showed superior HexA formation after treatment with both vectors (TSD α+β) and ganglioside clearance was most widespread in the TSD α+β high dose sheep. Microglial activation and proliferation in TSD sheep - most prominent in the cerebrum - were attenuated after gene therapy. This report demonstrates therapeutic efficacy for TSD in the sheep brain, which is in the same order of magnitude as a child's brain.
Tice, Bradley S.
Metrical phonology, a linguistic process of phonological stress assessment and diagrammatic simplification of sentence and word stress, is discussed as it is found in the English language with the intention that it may be used in second language instruction. Stress is defined by its physical and acoustical correlates, and the principles of…
1991-07-01
March 1979, pp. 121-128. Gorla, Narasimhaiah, Alan C. Benander, and Barbara A. Benander, "Debugging Effort Estimation Using Software Metrics", IEEE...Society, IEEE Guide for the Use of IEEE Standard Dictionary of Measures to Produce Reliable Software, IEEE Std 982.2-1988, June 1989. Jones, Capers
Adaptive metric kernel regression
DEFF Research Database (Denmark)
Goutte, Cyril; Larsen, Jan
2000-01-01
regression by minimising a cross-validation estimate of the generalisation error. This allows to automatically adjust the importance of different dimensions. The improvement in terms of modelling performance is illustrated on a variable selection task where the adaptive metric kernel clearly outperforms...
Adaptive Metric Kernel Regression
DEFF Research Database (Denmark)
Goutte, Cyril; Larsen, Jan
1998-01-01
by minimising a cross-validation estimate of the generalisation error. This allows one to automatically adjust the importance of different dimensions. The improvement in terms of modelling performance is illustrated on a variable selection task where the adaptive metric kernel clearly outperforms the standard...
Institute of Scientific and Technical Information of China (English)
MA Zhi-Hao
2008-01-01
Metric of quantum states plays an important role in quantum information theory. In this letter, we find the deep connection between quantum logic theory and quantum information theory. Using the method of quantum logic, we can get a famous inequality in quantum information theory, and we answer a question raised by S. Gudder.
Engineering performance metrics
Delozier, R.; Snyder, N.
1993-03-01
Implementation of a Total Quality Management (TQM) approach to engineering work required the development of a system of metrics which would serve as a meaningful management tool for evaluating effectiveness in accomplishing project objectives and in achieving improved customer satisfaction. A team effort was chartered with the goal of developing a system of engineering performance metrics which would measure customer satisfaction, quality, cost effectiveness, and timeliness. The approach to developing this system involved normal systems design phases including, conceptual design, detailed design, implementation, and integration. The lessons teamed from this effort will be explored in this paper. These lessons learned may provide a starting point for other large engineering organizations seeking to institute a performance measurement system accomplishing project objectives and in achieving improved customer satisfaction. To facilitate this effort, a team was chartered to assist in the development of the metrics system. This team, consisting of customers and Engineering staff members, was utilized to ensure that the needs and views of the customers were considered in the development of performance measurements. The development of a system of metrics is no different than the development of any type of system. It includes the steps of defining performance measurement requirements, measurement process conceptual design, performance measurement and reporting system detailed design, and system implementation and integration.
Argintar, Evan; Heckmann, Nathanael; Wang, Lawrence; Tibone, James E; Lee, Thay Q
2016-02-01
The purpose of this study was to determine the biomechanical effects of the remplissage repair combined with Bankart repair for engaging Hill-Sachs lesions on range of motion (ROM), translation, and glenohumeral kinematics. Six cadaveric shoulders were tested using a custom shoulder testing system. ROM, kinematics, and anterior-posterior (AP) and superior-inferior glenohumeral translations were quantified at 0° and 60° glenohumeral abduction. Six conditions were tested: intact, Bankart lesion, Bankart with 40 % Hill-Sachs lesion, Bankart repair, Bankart repair with remplissage, and remplissage repair alone. Humeral external rotation (ER) and total range of motion increased significantly after the creation of the Bankart lesion at both 0° and 60° abduction. The Bankart repair restored ER to intact values at 0° and 60° abduction, and the addition of the remplissage repair did not significantly alter range of motion from the Bankart repair alone. AP translation increased following the creation of the Bankart and Hill-Sachs lesions and was restored with the Bankart repair; the remplissage did not alter translation from the Bankart repair alone. At maximum ER at 60° abduction, the apex of the humeral head shifted posteriorly and inferiorly with remplissage repair. The addition of the remplissage procedure combined with Bankart repair for treatment of large Hill-Sachs lesions had no statistically significant effect on ROM or translation, but altered the kinematics of the glenohumeral joint. Thus, by addressing the humeral bone defect following an anterior shoulder dislocation, the remplissage technique with concurrent Bankart repair may be a relatively minimally invasive option for converting engaging Hill-Sachs lesions to non-engaging and promoting shoulder stability, though further biomechanical and clinical studies are warranted.
NPScape Metric GIS Data - Housing
National Park Service, Department of the Interior — NPScape housing metrics are calculated using outputs from the Spatially Explicit Regional Growth Model. Metric GIS datasets are produced seamlessly for the United...
Teukolsky, Saul A
2014-01-01
This review describes the events leading up to the discovery of the Kerr metric in 1963 and the enormous impact the discovery has had in the subsequent 50 years. The review discusses the Penrose process, the four laws of black hole mechanics, uniqueness of the solution, and the no-hair theorems. It also includes Kerr perturbation theory and its application to black hole stability and quasi-normal modes. The Kerr metric's importance in the astrophysics of quasars and accreting stellar-mass black hole systems is detailed. A theme of the review is the "miraculous" nature of the solution, both in describing in a simple analytic formula the most general rotating black hole, and in having unexpected mathematical properties that make many calculations tractable. Also included is a pedagogical derivation of the solution suitable for a first course in general relativity.
Metric adjusted skew information
DEFF Research Database (Denmark)
Hansen, Frank
2008-01-01
establish a connection between the geometrical formulation of quantum statistics as proposed by Chentsov and Morozova and measures of quantum information as introduced by Wigner and Yanase and extended in this article. We show that the set of normalized Morozova-Chentsov functions describing the possible...... quantum statistics is a Bauer simplex and determine its extreme points. We determine a particularly simple skew information, the "¿-skew information," parametrized by a ¿ ¿ (0, 1], and show that the convex cone this family generates coincides with the set of all metric adjusted skew informations.......We extend the concept of Wigner-Yanase-Dyson skew information to something we call "metric adjusted skew information" (of a state with respect to a conserved observable). This "skew information" is intended to be a non-negative quantity bounded by the variance (of an observable in a state...
Directory of Open Access Journals (Sweden)
Linda Bennett
2013-07-01
Full Text Available Continuing purchase of AHSS resources is threatened more by library budget squeezes than that of STM resources. Librarians must justify all expenditure, but quantitative metrical analysis to assess the value to the institution of journals and specialized research databases for AHSS subjects can be inconclusive; often the number of recorded transactions is lower than for STM, as the resource may be relevant to a smaller number of users. This paper draws on a literature review and extensive primary research, including a survey of 570 librarians and academics across the Anglophone countries, findings from focus group meetings and the analysis of user behaviour at a UK university before and after the installation of the Summon discovery system. It concludes that providing a new approach to metrics can help to develop resources strategies that meet changing user needs; and that usage statistics can be complemented with supplementary ROI measures to make them more meaningful.
Learning Sequence Neighbourhood Metrics
Bayer, Justin; van der Smagt, Patrick
2011-01-01
Recurrent neural networks (RNNs) in combination with a pooling operator and the neighbourhood components analysis (NCA) objective function are able to detect the characterizing dynamics of sequences and embed them into a fixed-length vector space of arbitrary dimensionality. Subsequently, the resulting features are meaningful and can be used for visualization or nearest neighbour classification in linear time. This kind of metric learning for sequential data enables the use of algorithms tailored towards fixed length vector spaces such as R^n.
Directory of Open Access Journals (Sweden)
Todd Carpenter
2015-07-01
Full Text Available An important and timely plenary session at the 2015 UKSG Conference and Exhibition focused on the role of metrics in research assessment. The two excellent speakers had slightly divergent views.Todd Carpenter from NISO (National Information Standards Organization argued that altmetrics aren’t alt anymore and that downloads and other forms of digital interaction, including social media reference, reference tracking, personal library saving, and secondary linking activity now provide mainstream approaches to the assessment of scholarly impact. James Wilsdon is professor of science and democracy in the Science Policy Research Unit at the University of Sussex and is chair of the Independent Review of the Role of Metrics in Research Assessment commissioned by the Higher Education Funding Council in England (HEFCE. The outcome of this review will inform the work of HEFCE and the other UK higher education funding bodies as they prepare for the future of the Research Excellence Framework. He is more circumspect arguing that metrics cannot and should not be used as a substitute for informed judgement. This article provides a summary of both presentations.
Depperschmidt, Andrej; Pfaffelhuber, Peter
2011-01-01
A marked metric measure space (mmm-space) is a triple (X,r,mu), where (X,r) is a complete and separable metric space and mu is a probability measure on XxI for some Polish space I of possible marks. We study the space of all (equivalence classes of) marked metric measure spaces for some fixed I. It arises as state space in the construction of Markov processes which take values in random graphs, e.g. tree-valued dynamics describing randomly evolving genealogical structures in population models. We derive here the topological properties of the space of mmm-spaces needed to study convergence in distribution of random mmm-spaces. Extending the notion of the Gromov-weak topology introduced in (Greven, Pfaffelhuber and Winter, 2009), we define the marked Gromov-weak topology, which turns the set of mmm-spaces into a Polish space. We give a characterization of tightness for families of distributions of random mmm- spaces and identify a convergence determining algebra of functions, called polynomials.
Geometry of manifolds with area metric: Multi-metric backgrounds
Energy Technology Data Exchange (ETDEWEB)
Schuller, Frederic P. [Perimeter Institute for Theoretical Physics, 31 Caroline Street N, Waterloo N2L 2Y5 (Canada) and Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, A. Postal 70-543, Mexico D.F. 04510 (Mexico)]. E-mail: fschuller@perimeterinstitute.ca; Wohlfarth, Mattias N.R. [II. Institut fuer Theoretische Physik, Universitaet Hamburg, Luruper Chaussee 149, 22761 Hamburg (Germany)]. E-mail: mattias.wohlfarth@desy.de
2006-07-24
We construct the differential geometry of smooth manifolds equipped with an algebraic curvature map acting as an area measure. Area metric geometry provides a spacetime structure suitable for the discussion of gauge theories and strings, and is considerably more general than Lorentzian geometry. Our construction of geometrically relevant objects, such as an area metric compatible connection and derived tensors, makes essential use of a decomposition theorem due to Gilkey, whereby we generate the area metric from a finite collection of metrics. Employing curvature invariants for multi-metric backgrounds we devise a class of gravity theories with inherently stringy character, and discuss gauge matter actions.
Some References on Metric Information.
National Bureau of Standards (DOC), Washington, DC.
This resource work lists metric information published by the U.S. Government and the American National Standards Institute. Also organizations marketing metric materials for education are given. A short table of conversions is included as is a listing of basic metric facts for everyday living. (LS)
Projectively related complex Finsler metrics
Aldea, Nicoleta
2011-01-01
In this paper we introduce in study the projectively related complex Finsler metrics. We prove the complex versions of the Rapcs\\'{a}k's theorem and characterize the weakly K\\"{a}hler and generalized Berwald projectively related complex Finsler metrics. The complex version of Hilbert's Fourth Problem is also pointed out. As an application, the projectiveness of a complex Randers metric is described.
An Optimal Approach for Measuring the Integrated Sachs-Wolfe Effect
Dupe, F -X; Starck, J -L; Fadili, M J
2010-01-01
One of the main challenges of modern cosmology is to understand the primordial fluctuations of the early Universe and the nature of the mysterious dark energy which causes the cosmic acceleration. The Integrated Sachs-Wolfe (ISW) effect is sensitive to dark energy, and if reconstructed can be used to study primordial fluctuations in the CMB. The ISW effect occurs on large scales, where there are large amounts of missing data in the CMB and large scale structure maps. Moreover, existing methods in the literature often make strong assumptions about the statistics of the underlying fields or estimators. Together these effects can severely limit signal extraction. We define an optimal statistical method for detecting the ISW effect, which can handle large areas of missing data and minimise the number of underlying assumptions made about the data and estimators. We first review current detections (and non-detections) of the ISW effect, comparing the statistical subtleties of different methods found in the literatu...
Community-based genetic education, communication channels, and knowledge of Tay-Sachs disease.
Massarik, F; Kaback, M M; Greenwald, S; Nathan, T J; Rosenthal, M; Bass, D M
1977-01-01
In the planning of community-based genetics education campaigns, we cannot assume the existence of a single-minded, passively receptive public, simply waiting to be "educated." Rather, we must consider the impact of preexisting circumstances, notably the differential life-status conditions, the special concerns, and individual motivations of the persons to be educated on their search for information that matters to them. Messages promulgated by mass media educational campaigns on issues in genetics typically do not fall on a homogeneous mass of equally responsive ears and eyes, even if the target population superficially appears to be homogeneous and preselected. Especially institutional sources, (e.g., schools and general education) for males, and social relations (e.g., informal contact among friends) for females are crucial strategic variables affecting transmission and reception of knowledge of Tay-Sachs disease.
Cross-correlation between thermal Sunyaev-Zeldovich effect and the integrated Sachs-Wolfe effect
Creque-Sarbinowski, Cyril; Bird, Simeon; Kamionkowski, Marc
2016-09-01
Large-angle fluctuations in the cosmic microwave background temperature induced by the integrated Sachs-Wolfe effect and Compton-y distortions from the thermal Sunyaev-Zeldovich (tSZ) effect are both due to line-of-sight density perturbations. Here we calculate the cross-correlation between these two signals. Measurement of this cross-correlation can be used to test the redshift distribution of the tSZ distortion, which has implications for the redshift at which astrophysical processes in clusters begin to operate. We also evaluate the detectability of a y T cross-correlation from exotic early-Universe sources in the presence of this late-time effect.
Probing the integrated Sachs-Wolfe effect using embedded lens models
Chen, Bin
2015-01-01
The photometry profile of the integrated Sachs-Wolfe (ISW) effect recently obtained by the Planck consortium by stacking patches of Cosmic Microwave Background (CMB) sky maps around a large number of cosmic voids, contains a cold ring at about half the void's effective radius surrounded by a hot ring near the void's boundary. The source of the temperature structure is assumed to be the ISW effect but the exact cause of the ringed structure is not currently well understood, particularly the outer hot ring. Numerical simulations have suggested that hot/cold ring structures can be produced by motions associated with nonlinear growths of cosmic structures whose gravitational potentials produce the ISW effect. We have recently developed the embedded lens theory and the Fermat potential formalism which can be used to model the ISW effect caused by intervening individual lens inhomogeneities evolving arbitrarily. This theory only requires knowledge of the void's projected mass profile as a function of the passing CM...
A Unification of G-Metric, Partial Metric, and b-Metric Spaces
Directory of Open Access Journals (Sweden)
Nawab Hussain
2014-01-01
Full Text Available Using the concepts of G-metric, partial metric, and b-metric spaces, we define a new concept of generalized partial b-metric space. Topological and structural properties of the new space are investigated and certain fixed point theorems for contractive mappings in such spaces are obtained. Some examples are provided here to illustrate the usability of the obtained results.
Hill-Sachs lesion location: does it play a role in engagement?
Energy Technology Data Exchange (ETDEWEB)
Gyftopoulos, Soterios; Wang, Annie; Babb, James [NYU Langone Medical Center, Department of Radiology, New York, NY (United States)
2015-08-15
To see if there is an association between engagement on physical examination (PE) and the location of the Hill-Sachs lesion (HSL) as assessed by the modified biceps angle. Sixty-two patients with a history of anterior shoulder dislocation, who underwent preoperative MRI and arthroscopy at our institution and were tested for engagement on PE, were collected. Two musculoskeletal radiologists reviewed the MR studies, noting the presence of an HSL and documenting the location of the HSL with the modified biceps angle. Statistical analysis included the Mann-Whitney (MW) test and ROC (receiver-operating characteristic) curve. Of 62 patients, there were 58 males and 4 females with a mean age of 30 (range 18-59 years). Twenty patients demonstrated engagement on PE, while 42 did not. All patients had evidence of an HSL on MRI and arthroscopy. The mean biceps angle for the engaging group was 151.5 ± 13.9 , and 142.4 ± 17.3 for the non-engaging group. The biceps angle was statistically significantly higher among patients who had engagement compared to those who did not (p = 0.027). Overall, diagnostic accuracy was highest for a biceps angle >149 , which resulted in a sensitivity of 70 % and specificity of 67 %. The modified biceps angle, as measured on MRI, was significantly higher in patients who demonstrated engagement on physical examination than in those who did not. This supports the theory that the location of the Hill-Sachs lesion may play a role in engagement and may be its most important characteristic when determining its significance. (orig.)
Degenerate pseudo-Riemannian metrics
Hervik, Sigbjorn; Yamamoto, Kei
2014-01-01
In this paper we study pseudo-Riemannian spaces with a degenerate curvature structure i.e. there exists a continuous family of metrics having identical polynomial curvature invariants. We approach this problem by utilising an idea coming from invariant theory. This involves the existence of a boost, the existence of this boost is assumed to extend to a neighbourhood. This approach proves to be very fruitful: It produces a class of metrics containing all known examples of degenerate metrics. To date, only Kundt and Walker metrics have been given, however, our study gives a plethora of examples showing that degenerate metrics extend beyond the Kundt and Walker examples. The approach also gives a useful criterion for a metric to be degenerate. Specifically, we use this to study the subclass of VSI and CSI metrics (i.e., spaces where polynomial curvature invariants are all vanishing or constants, respectively).
2016-03-02
520, 2004. 16 [12] E.C. Hall and R.M. Willett. Online convex optimization in dynamic environ- ments. Selected Topics in Signal Processing, IEEE Journal...Conference on Machine Learning, pages 1160–1167. ACM, 2008. [25] Eric P Xing, Michael I Jordan, Stuart Russell, and Andrew Y Ng. Distance metric...whereBψ is any Bregman divergence and ηt is the learning rate parameter. From ( Hall & Willett, 2015) we have: Theorem 1. G` = max θ∈Θ,`∈L ‖∇f(θ)‖ φmax = 1
Metrics for Multiagent Systems
Lass, Robert N.; Sultanik, Evan A.; Regli, William C.
A Multiagent System (MAS) is a software paradigm for building large scale intelligent distributed systems. Increasingly these systems are being deployed on handheld computing devices that rely on non-traditional communications mediums such as mobile ad hoc networks and satellite links. These systems present new challenges for computer scientists in describing system performance and analyzing competing systems. This chapter surveys existing metrics that can be used to describe MASs and related components. A framework for analyzing MASs is provided and an example of how this framework might be employed is given for the domain of distributed constraint reasoning.
Sustainable chemistry metrics.
Calvo-Flores, Francisco García
2009-01-01
Green chemistry has developed mathematical parameters to describe the sustainability of chemical reactions and processes, in order to quantify their environmental impact. These parameters are related to mass and energy magnitudes, and enable analyses and numerical diagnoses of chemical reactions. The environmental impact factor (E factor), atom economy, and reaction mass efficiency have been the most influential metrics, and they are interconnected by mathematical equations. The ecodesign concept must also be considered for complex industrial syntheses, as a part of the sustainability of manufacturing processes. The aim of this Concept article is to identify the main parameters for evaluating undesirable environmental consequences.
Hayase, Tomomi; Shimizu, Jun; Goto, Tamako; Nozaki, Yasuyuki; Mori, Masato; Takahashi, Naoto; Namba, Eiji; Yamagata, Takanori; Momoi, Mariko Y
2010-03-01
We report the case of a girl with Tay-Sachs disease who had convulsions and deteriorated rapidly after an upper respiratory infection at the age of 11 months. At the age of 16 months, her seizures became intractable and magnetic resonance imaging of the brain showed high signal intensity on T2-weighted images and marked swelling in the white matter and basal nucelei of the right hemisphere. Her seizures and right hemisphere lesion improved with glycerol and dexamethasone treatment. When dexamethasone was discontinued, her symptoms worsened and lesions later appeared in the left hemisphere. Her cerebrospinal fluid showed elevated levels of the cytokines TNF-alpha and IL-5. It is considered that inflammation contributes to disease progression in Tay-Sachs disease.
Schubert, Mathias
2016-11-18
A coordinate-invariant generalization of the Lyddane-Sachs-Teller relation is presented for polar vibrations in materials with monoclinic and triclinic crystal systems. The generalization is derived from an eigendielectric displacement vector summation approach, which is equivalent to the microscopic Born-Huang description of polar lattice vibrations in the harmonic approximation. An expression for a general oscillator strength is also described for materials with monoclinic and triclinic crystal systems. A generalized factorized form of the dielectric response characteristic for monoclinic and triclinic materials is proposed. The generalized Lyddane-Sachs-Teller relation is found valid for monoclinic β-Ga_{2}O_{3}, where accurate experimental data became available recently from a comprehensive generalized ellipsometry investigation [Phys. Rev. B 93, 125209 (2016)]. Data for triclinic crystal systems can be measured by generalized ellipsometry as well, and are anticipated to become available soon and results can be compared with the generalized relations presented here.
The molecular basis of HEXA mRNA deficiency caused by the most common Tay-Sachs disease mutation.
Boles, D. J.; Proia, R L
1995-01-01
Tay-Sachs disease (TSD) is a catastrophic neurodegenerative disorder caused by mutations in the HEXA gene. The most common TSD allele worldwide contains a 4-bp insertion in exon 11 that produces a downstream premature termination codon. Despite normal transcription of this allele, HEXA mRNA is severely reduced, indicating that the HEXA transcript must be unstable. Minigenes of HEXA were constructed and expressed in mouse L cells, to investigate the relationship between the 4-bp insertion and ...
A poeta das “moradas da morte”. Sobre a obra lírica de Nelly Sachs
Directory of Open Access Journals (Sweden)
Helmut Galle
2006-12-01
Full Text Available Der Artikel behandelt die deutschsprachige Dichterin Nelly Sachs, die 1966 mit Shmuel Agnon den Nobelpreis für Literatur erhielt. In der Absicht, die Gründe für die Entscheidung der Jury zu beleuchten, wird ein Überblick über Leben und Werk der Autorin gegeben und einige ausgewählte Gedichte analysiert.
Karimzadeh, Parvaneh; Jafari, Narjes; Nejad Biglari, Habibeh; Jabbeh Dari, Sayena; Ahmad Abadi, Farzad; Alaee, Mohammad-Reza; Nemati, Hamid; Saket, Sasan; Tonekaboni, Seyed Hasan; Taghdiri, Mohammad-Mahdi; Ghofrani, Mohammad
2014-01-01
GM2-Gangliosidosis disease is a rare autosomal recessive genetic disorder that includes two disorders (Tay-Sachs and Sandhoff disease).These disorders cause a progressive deterioration of nerve cells and inherited deficiency in creating hexosaminidases A, B, and AB. Patients who were diagnosed withGM2-Gangliosidosis in the Neurology Department of Mofid Children's Hospital in Tehran, Iran from October 2009 to February 2014were included in our study. The disorder was confirmed by neurometabolic and enzyme level detection of hexosaminidases A, B, and AB in reference to Wagnester Laboratory in Germany. We assessed age, gender, past medical history, developmental status, clinical manifestations, and neuroimaging findings of 9 patients with Sandhoff disease and 9 with Tay Sachs disease. 83% of our patients were the offspring of consanguineous marriages. All of them had a developmental disorder as a chief complaint. 38%of patients had a history of developmental delay or regression and 22% had seizures. The patients with Sandhoff and Tay Sachs disease were followed for approximately 5 years and the follow-up showed all patients were bedridden or had expired due to refractory seizures, pneumonia aspiration, or swallowing disorders. Neuro-imaging findings included bilateral thalamic involvement, brain atrophy, and hypo myelination in near half of our patients (48%). According to the results of this study, we suggest that cherry-red spots, hyperacusis, refractory seizures, and relative parents in children with developmental delay and/or regression should be considered for assessment of GM2-Gangliosidosis disease.
Metric-adjusted skew information
DEFF Research Database (Denmark)
Liang, Cai; Hansen, Frank
2010-01-01
We give a truly elementary proof of the convexity of metric-adjusted skew information following an idea of Effros. We extend earlier results of weak forms of superadditivity to general metric-adjusted skew information. Recently, Luo and Zhang introduced the notion of semi-quantum states on a bipa......We give a truly elementary proof of the convexity of metric-adjusted skew information following an idea of Effros. We extend earlier results of weak forms of superadditivity to general metric-adjusted skew information. Recently, Luo and Zhang introduced the notion of semi-quantum states...
Canonical metrics on complex manifold
Institute of Scientific and Technical Information of China (English)
YAU Shing-Tung
2008-01-01
@@ Complex manifolds are topological spaces that are covered by coordinate charts where the Coordinate changes are given by holomorphic transformations. For example, Riemann surfaces are one dimensional complex manifolds. In order to understand complex manifolds, it is useful to introduce metrics that are compatible with the complex structure. In general, we should have a pair (M, ds2M) where ds2M is the metric. The metric is said to be canonical if any biholomorphisms of the complex manifolds are automatically isometries. Such metrics can naturally be used to describe invariants of the complex structures of the manifold.
Canonical metrics on complex manifold
Institute of Scientific and Technical Information of China (English)
YAU; Shing-Tung(Yau; S.-T.)
2008-01-01
Complex manifolds are topological spaces that are covered by coordinate charts where the coordinate changes are given by holomorphic transformations.For example,Riemann surfaces are one dimensional complex manifolds.In order to understand complex manifolds,it is useful to introduce metrics that are compatible with the complex structure.In general,we should have a pair(M,ds~2_M)where ds~2_M is the metric.The metric is said to be canonical if any biholomorphisms of the complex manifolds are automatically isometries.Such metrics can naturally be used to describe invariants of the complex structures of the manifold.
The metric system: An introduction
Lumley, Susan M.
On 13 Jul. 1992, Deputy Director Duane Sewell restated the Laboratory's policy on conversion to the metric system which was established in 1974. Sewell's memo announced the Laboratory's intention to continue metric conversion on a reasonable and cost effective basis. Copies of the 1974 and 1992 Administrative Memos are contained in the Appendix. There are three primary reasons behind the Laboratory's conversion to the metric system. First, Public Law 100-418, passed in 1988, states that by the end of fiscal year 1992 the Federal Government must begin using metric units in grants, procurements, and other business transactions. Second, on 25 Jul. 1991, President George Bush signed Executive Order 12770 which urged Federal agencies to expedite conversion to metric units. Third, the contract between the University of California and the Department of Energy calls for the Laboratory to convert to the metric system. Thus, conversion to the metric system is a legal requirement and a contractual mandate with the University of California. Public Law 100-418 and Executive Order 12770 are discussed in more detail later in this section, but first they examine the reasons behind the nation's conversion to the metric system. The second part of this report is on applying the metric system.
Directory of Open Access Journals (Sweden)
Isabel Garrido
2016-04-01
Full Text Available The class of metric spaces (X,d known as small-determined spaces, introduced by Garrido and Jaramillo, are properly defined by means of some type of real-valued Lipschitz functions on X. On the other hand, B-simple metric spaces introduced by Hejcman are defined in terms of some kind of bornologies of bounded subsets of X. In this note we present a common framework where both classes of metric spaces can be studied which allows us to see not only the relationships between them but also to obtain new internal characterizations of these metric properties.
Doença de Tay-Sachs: um relato de caso
Directory of Open Access Journals (Sweden)
Marta Wey Vieira
2014-10-01
Full Text Available Introdução: a doença de Tay-Sachs (DTS é uma doença autossômica recessiva neurodegenerativa, com início na infância, sendo caracterizada pelo retardo no desenvolvimento, seguido de paralisia, demência e cegueira. É causada por uma mutação no gene HEXA, identificado no cromossomo 15q23-q244, que é responsável pela codificação da subunidade da enzima Hex A1. Essa mutação acaba por permitir que haja um acúmulo intralisossomal de gangliosídeo GM2 nas células neuronais. Objetivo: Relatar um caso de DTS do serviço de Pediatria em um hospital em Sorocaba. Descrição do Caso: paciente do sexo feminino com 5 anos de idade, encaminhada ao serviço de genética-clínica por apresentar retardo no desenvolvimento neuropsicomotor a esclarecer, cuja 2ª triagem ampliada para erros inatos do metabolismo revelou hexosaminidase A não detectável e hexosaminidase A-MUGS de 15nmol/h/mgprot (nl:150-390nmol/h/mgprot, compatível com o diagnóstico de Doença de Tay-Sachs. Comentários: há três variantes da DTS, a forma apresentada pela paciente do caso pode ser a juvenil (subaguda ou a forma adulta (crônica. O tratamento para a DTS é restringe-se ao suporte das manifestações clínicas e manejo adequado das intercorrências e doenças infecciosas com a manutenção adequada da nutrição e da hidratação, além do controle das convulsões quando estas ocorrerem. Entretanto, técnicas têm sido desenvolvidas no intuito de encontrar alguma terapia viável e efetiva, como por exemplo: terapias de reposição enzimática (TRE, terapias de moléculas pequenas chamadas chaperonas farmacológicas (PC, terapia de privação de substrato o transplante de medula óssea, terapia gênica mediada por vetor retroviral e a liberação de genes diretamente no sistema nervoso central. Conclusão: A doença de Tay-Sachs (DTS é uma doença neurodegenerativa, causada por uma mutação genética. O diagnóstico pode ser feito ainda durante o pr
Software metrics: Software quality metrics for distributed systems. [reliability engineering
Post, J. V.
1981-01-01
Software quality metrics was extended to cover distributed computer systems. Emphasis is placed on studying embedded computer systems and on viewing them within a system life cycle. The hierarchy of quality factors, criteria, and metrics was maintained. New software quality factors were added, including survivability, expandability, and evolvability.
Directory of Open Access Journals (Sweden)
Mehul Mistri
Full Text Available Tay Sachs disease (TSD is a neurodegenerative disorder due to β-hexosaminidase A deficiency caused by mutations in the HEXA gene. The mutations leading to Tay Sachs disease in India are yet unknown. We aimed to determine mutations leading to TSD in India by complete sequencing of the HEXA gene. The clinical inclusion criteria included neuroregression, seizures, exaggerated startle reflex, macrocephaly, cherry red spot on fundus examination and spasticity. Neuroimaging criteria included thalamic hyperdensities on CT scan/T1W images of MRI of the brain. Biochemical criteria included deficiency of hexosaminidase A (less than 2% of total hexosaminidase activity for infantile patients. Total leukocyte hexosaminidase activity was assayed by 4-methylumbelliferyl-N-acetyl-β-D-glucosamine lysis and hexosaminidase A activity was assayed by heat inactivation method and 4-methylumbelliferyl-N-acetyl-β-D-glucosamine-6-sulphate lysis method. The exons and exon-intron boundaries of the HEXA gene were bidirectionally sequenced using an automated sequencer. Mutations were confirmed in parents and looked up in public databases. In silico analysis for mutations was carried out using SIFT, Polyphen2, MutationT@ster and Accelrys Discovery Studio softwares. Fifteen families were included in the study. We identified six novel missense mutations, c.340 G>A (p.E114K, c.964 G>A (p.D322N, c.964 G>T (p.D322Y, c.1178C>G (p.R393P and c.1385A>T (p.E462V, c.1432 G>A (p.G478R and two previously reported mutations. c.1277_1278insTATC and c.508C>T (p.R170W. The mutation p.E462V was found in six unrelated families from Gujarat indicating a founder effect. A previously known splice site mutation c.805+1 G>C and another intronic mutation c.672+30 T>G of unknown significance were also identified. Mutations could not be identified in one family. We conclude that TSD patients from Gujarat should be screened for the common mutation p.E462V.
Mistri, Mehul; Tamhankar, Parag M; Sheth, Frenny; Sanghavi, Daksha; Kondurkar, Pratima; Patil, Swapnil; Idicula-Thomas, Susan; Gupta, Sarita; Sheth, Jayesh
2012-01-01
Tay Sachs disease (TSD) is a neurodegenerative disorder due to β-hexosaminidase A deficiency caused by mutations in the HEXA gene. The mutations leading to Tay Sachs disease in India are yet unknown. We aimed to determine mutations leading to TSD in India by complete sequencing of the HEXA gene. The clinical inclusion criteria included neuroregression, seizures, exaggerated startle reflex, macrocephaly, cherry red spot on fundus examination and spasticity. Neuroimaging criteria included thalamic hyperdensities on CT scan/T1W images of MRI of the brain. Biochemical criteria included deficiency of hexosaminidase A (less than 2% of total hexosaminidase activity for infantile patients). Total leukocyte hexosaminidase activity was assayed by 4-methylumbelliferyl-N-acetyl-β-D-glucosamine lysis and hexosaminidase A activity was assayed by heat inactivation method and 4-methylumbelliferyl-N-acetyl-β-D-glucosamine-6-sulphate lysis method. The exons and exon-intron boundaries of the HEXA gene were bidirectionally sequenced using an automated sequencer. Mutations were confirmed in parents and looked up in public databases. In silico analysis for mutations was carried out using SIFT, Polyphen2, MutationT@ster and Accelrys Discovery Studio softwares. Fifteen families were included in the study. We identified six novel missense mutations, c.340 G>A (p.E114K), c.964 G>A (p.D322N), c.964 G>T (p.D322Y), c.1178C>G (p.R393P) and c.1385A>T (p.E462V), c.1432 G>A (p.G478R) and two previously reported mutations. c.1277_1278insTATC and c.508C>T (p.R170W). The mutation p.E462V was found in six unrelated families from Gujarat indicating a founder effect. A previously known splice site mutation c.805+1 G>C and another intronic mutation c.672+30 T>G of unknown significance were also identified. Mutations could not be identified in one family. We conclude that TSD patients from Gujarat should be screened for the common mutation p.E462V.
Metrical Phonology: German Sound System.
Tice, Bradley S.
Metrical phonology, a linguistic process of phonological stress assessment and diagrammatic simplification of sentence and word stress, is discussed as it is found in the English and German languages. The objective is to promote use of metrical phonology as a tool for enhancing instruction in stress patterns in words and sentences, particularly in…
Metrics for Hard Goods Merchandising.
Cooper, Gloria S., Ed.; Magisos, Joel H., Ed.
Designed to meet the job-related metric measurement needs of students interested in hard goods merchandising, this instructional package is one of five for the marketing and distribution cluster, part of a set of 55 packages for metric instruction in different occupations. The package is intended for students who already know the occupational…
Metrics for Soft Goods Merchandising.
Cooper, Gloria S., Ed.; Magisos, Joel H., Ed.
Designed to meet the job-related metric measurement needs of students interested in soft goods merchandising, this instructional package is one of five for the marketing and distribution cluster, part of a set of 55 packages for metric instruction in different occupations. The package is intended for students who already know the occupational…
Conversion to the Metric System
Crunkilton, John C.; Lee, Jasper S.
1974-01-01
The authors discuss background information about the metric system and explore the effect of metrication of agriculture in areas such as equipment calibration, chemical measurement, and marketing of agricultural products. Suggestions are given for possible leadership roles and approaches that agricultural education might take in converting to the…
Douglas, M R; Lukic, S; Reinbacher, R; Douglas, Michael R.; Karp, Robert L.; Lukic, Sergio; Reinbacher, Rene
2006-01-01
We develop numerical methods for approximating Ricci flat metrics on Calabi-Yau hypersurfaces in projective spaces. Our approach is based on finding balanced metrics, and builds on recent theoretical work by Donaldson. We illustrate our methods in detail for a one parameter family of quintics. We also suggest several ways to extend our results.
Metric Supplement to Technical Drawing.
Henschel, Mark
This manual is intended for use in training persons whose vocations involve technical drawing to use the metric system of measurement. It could be used in a short course designed for that purpose or for individual study. The manual begins with a brief discussion of the rationale for conversion to the metric system. It then provides a…
Aksoy, Asuman Guven
2010-01-01
Using isometric embedding of metric trees into Banach spaces, this paper will investigate barycenters, type and cotype, and various measures of compactness of metric trees. A metric tree ($T$, $d$) is a metric space such that between any two of its points there is an unique arc that is isometric to an interval in $\\mathbb{R}$. We begin our investigation by examining isometric embeddings of metric trees into Banach spaces. We then investigate the possible images $x_0=\\pi ((x_1+\\ldots+x_n)/n)$, where $\\pi$ is a contractive retraction from the ambient Banach space $X$ onto $T$ (such a $\\pi$ always exists) in order to understand the "metric" barycenter of a family of points $ x_1, \\ldots,x_n$ in a tree $T$. Further, we consider the metric properties of trees such as their type and cotype. We identify various measures of compactness of metric trees (their covering numbers, $\\epsilon$-entropy and Kolmogorov widths) and the connections between them. Additionally, we prove that the limit of the sequence of Kolmogorov...
Generalized metric spaces and mappings
Lin, Shou
2016-01-01
The idea of mutual classification of spaces and mappings is one of the main research directions of point set topology. In a systematical way, this book discusses the basic theory of generalized metric spaces by using the mapping method, and summarizes the most important research achievements, particularly those from Chinese scholars, in the theory of spaces and mappings since the 1960s. This book has three chapters, two appendices and a list of more than 400 references. The chapters are "The origin of generalized metric spaces", "Mappings on metric spaces" and "Classes of generalized metric spaces". Graduates or senior undergraduates in mathematics major can use this book as their text to study the theory of generalized metric spaces. Researchers in this field can also use this book as a valuable reference.
Spontaneous appearance of Tay-Sachs disease in an animal model.
Zeng, B J; Torres, P A; Viner, T C; Wang, Z H; Raghavan, S S; Alroy, J; Pastores, G M; Kolodny, E H
2008-01-01
Tay-Sachs disease (TSD) is a progressive neurodegenerative disorder due to an autosomal recessively inherited deficiency of beta-hexosaminidase A (Hex A). Deficiency of Hex A in TSD is caused by a defect of the alpha-subunit resulting from mutations of the HEXA gene. To date, there is no effective treatment for TSD. Animal models of genetic diseases, similar to those known to exist in humans, are valuable and essential research tools for the study of potentially effective therapies. However, there is no ideal animal model of TSD available for use in therapeutic trials. In the present study, we report an animal model (American flamingo; Phoenicopterus ruber) of TSD with Hex A deficiency occurring spontaneously in nature, with accumulation of G(M2)-ganglioside, deficiency of Hex A enzymatic activity, and a homozygous P469L mutation in exon 12 of the hexa gene. In addition, we have isolated the full-length cDNA sequence of the flamingo, which consists of 1581 nucleotides encoding a protein of 527 amino acids. Its coding sequence indicates approximately 71% identity at the nucleotide level and about 72.5% identity at the amino acid level with the encoding region of the human HEXA gene. This animal model, with many of the same features as TSD in humans, could represent a valuable resource for investigating therapy of TSD.
The Integrated Sachs-Wolfe effect in $f(R)$ gravity
Cai, Yan-Chuan; Cole, Shaun; Frenk, Carlos S; Neyrinck, Mark
2013-01-01
We study the late-time Integrated Sachs-Wolfe (ISW) effect in $f(R)$ modified gravity using N-body simulations. In the $f(R)$ model under study, the linear growth rate is larger than that in general relativity (GR) due to the enhancement of gravity. This counters the effect of cosmic acceleration at late times, thus slowing down the decay of the cosmic potential and induces a smaller ISW effect on large scales. Therefore, the $\\dot\\Phi$ (time derivative of the potential) power spectrum at the Fourier $k$ range of $k0.1h$/Mpc is increased. The difference between the $\\dot\\Phi$ power spectrum in $f(R)$ and GR reaches 100% on small scales at z=0. In contrast, the differences in the density power spectrum is only 50%. We explore the detectability of the ISW signal via stacking supervoids and superclusters in simulations. For relatively large ISW cold spots, they are less cold in $f(R)$ than in GR, while small cold spots are colder. ISW hot spots corresponding to the stacking of superclusters in $f(R)$ are not as ...
Lew, Raelia M; Burnett, Leslie; Proos, Anné L; Barlow-Stewart, Kristine; Delatycki, Martin B; Bankier, Agnes; Aizenberg, Harry; Field, Michael J; Berman, Yemima; Fleischer, Ronald; Fietz, Michael
2015-03-01
Internationally, Tay-Sachs disease (TSD) preconception screening of Ashkenazi Jewish (AJ) individuals and couples has led to effective primary prevention of TSD. In Australia, adolescent preconception genetic screening programs operate mainly in Jewish community high schools. These existing programs offer an effective means of primary prevention of TSD, are cost effective and safe. However, in the broader Australian community TSD screening is not systematically performed and cases still occur in unscreened AJ individuals. In order to improve the effectiveness of Australian screening, there is a need for definitive guidelines for healthcare professionals to facilitate extension of the proven benefits of preconception TSD screening to all AJ individuals at risk. We performed a systematic review of the relevant literature relating to AJ pre-conception and antenatal screening for TSD. The evidence was assessed using an established National Health and Medical Research Council evidence grading system. Evaluations of efficacy of TSD screening programs design and execution, cost-benefit and cost-utility health economic evaluation, and population outcomes were undertaken. The results have been used to propose a model for universal AJ TSD preconception and antenatal screening for the primary care setting. © 2014 The Authors. Journal of Paediatrics and Child Health © 2014 Paediatrics and Child Health Division (Royal Australasian College of Physicians).
Three novel mutations in Iranian patients with Tay-Sachs disease.
Jamali, Solmaz; Eskandari, Nasim; Aryani, Omid; Salehpour, Shadab; Zaman, Talieh; Kamalidehghan, Behnam; Houshmand, Massoud
2014-01-01
Tay-Sachs disease (TSD), or GM2 gangliosidosis, is a lethal autosomal recessive neurodegenerative disorder, which is caused by a deficiency of beta-hexosaminidase A (HEXA), resulting in lysosomal accumulation of GM2 ganglioside. The aim of this study was to identify the TSD-causing mutations in an Iranian population. In this study, we examined 31 patients for TSD-causing mutations using PCR, followed by restriction enzyme digestion. Molecular genetics analysis of DNA from 23 patients of TSD revealed mutations that has been previously reported, including four-base duplications c.1274_1277dupTATC in exon 11 and IVS2+1G>A, deletion TTAGGCAAGGGC in exon 10 as well as a few novel mutations, including C331G, which altered Gln>Glu in HEXB, A>G, T>C, and p.R510X in exon 14, which predicted a termination codon or nonsense mutation. In conclusion, with the discovery of these novel mutations, the genotypic spectrum of Iranian patients with TSD disease has been extended and could facilitate definition of disease-related mutations.
Detecting the integrated Sachs-Wolfe effect with high-redshift 21-cm surveys
Raccanelli, Alvise; Dai, Liang; Kamionkowski, Marc
2015-01-01
We investigate the possibility to detect the integrated Sachs-Wolfe (ISW) effect by cross-correlating 21-cm surveys at high redshifts with galaxies, in a way similar to the usual CMB-galaxy cross-correlation. The high-redshift 21-cm signal is dominated by CMB photons that travel freely without interacting with the intervening matter, and hence its late-time ISW signature should correlate extremely well with that of the CMB at its peak frequencies. Using the 21-cm temperature brightness instead of the CMB would thus be a further check of the detection of the ISW effect, measured by different instruments at different frequencies and suffering from different systematics. We also study the ISW effect on the photons that are scattered by HI clouds. We show that a detection of the unscattered photons is achievable with planned radio arrays, while one using scattered photons will require advanced radio interferometers, either an extended version of the planned Square Kilometre Array or futuristic experiments such as...
Measurement of the integrated Sachs-Wolfe effect using the AllWISE data release
Shajib, Anowar J
2016-01-01
One of the physical features of a dark-energy-dominated universe is the integrated Sachs-Wolfe (ISW) effect on the cosmic microwave background (CMB) radiation, which gives us a direct observational window to detect and study dark energy. The AllWISE data release of the Wide-field Infrared Survey Explorer (WISE) has a large number of point sources, which span over a wide redshift range including where the ISW effect is maximized. AllWISE data is thus very well-suited for the ISW effect studies. In this study, we cross-correlate AllWISE galaxy and active galactic nucleus (AGN) overdensities with the Wilkinson Microwave Anisotropy Probe CMB temperature maps to detect the ISW effect signal. We calibrate the biases for galaxies and AGNs by cross-correlating the galaxy and AGN overdensities with the Planck lensing convergence map. We measure the ISW effect signal amplitudes relative to the {\\Lambda}CDM expectation of $A=1$ to be $A=1.18 \\pm 0.36$ for galaxies and $A=0.64 \\pm 0.74$ for AGNs . The detection significa...
The cross-correlation between 3d cosmic shear and the integrated Sachs-Wolfe effect
Zieser, Britta
2016-01-01
We present the first calculation of the cross-correlation between three-dimensional cosmic shear and the integrated Sachs-Wolfe (iSW) effect. Both signals are combined in a single formalism, which permits the computation of the full covariance matrix. In order to avoid the uncertainties presented by the non-linear evolution of the matter power spectrum and intrinsic alignments of galaxies, our analysis is restricted to large scales, i.e. multipoles below l=1000. We demonstrate in a Fisher analysis that this reduction compared to other studies of three-dimensional weak lensing extending to smaller scales is compensated by the information that is gained if the additional iSW signal and in particular its cross-correlation with lensing data are considered. Given the observational standards of upcoming weak lensing surveys like Euclid, marginal errors on cosmological parameters decrease by ten per cent compared to a cosmic shear experiment if both types of information are combined without a CMB prior. Once the con...
Correlating the CMB with Luminous Red Galaxies The Integrated Sachs-Wolfe Effect
Padmanabhan, N; Seljak, U; Schlegel, D J; Brinkmann, J; Schneider, D P; Padmanabhan, Nikhil; Hirata, Christopher M.; Seljak, Uros; Schlegel, David; Brinkmann, Jonathan; Schneider, Donald P.
2004-01-01
We present a 2.5 sigma detection of the Integrated Sachs-Wolfe (ISW) effect and discuss the constraints it places on cosmological parameters. We cross-correlate microwave temperature maps from the WMAP satellite with a 4000 deg^2 luminous red galaxy (LRG) overdensity map measured by the Sloan Digital Sky Survey. Accurate photometric redshifts allow us to perform a reliable auto-correlation analysis of the LRGs, eliminating the uncertainty in the galaxy bias, and combined with cross correlation signal, constrains cosmological parameters -- in particular, the matter density. We find a 2.5 sigma signal in the Ka, Q, V, and W WMAP bands, after combining the information from multipoles 2 <= l < 400. This is consistent with the expected amplitude of the ISW effect, but requires a lower matter density than is usually assumed: the amplitude, parametrized by the galaxy bias assuming \\Omega_M=0.3, \\Omega_\\Lambda=0.7 and \\sigma_8=0.9, is b_g = 4.05 \\pm 1.54 for V band, with similar results for the other bands. Thi...
Hernandez-Monteagudo, Carlos; Cuesta, Antonio; Genova-Santos, Ricardo; Prada, Francisco; Rossi, Graziano; Neyrinck, Mark; Viel, Matteo; Rubino-Martin, Jose-Alberto; Scoccola, Claudia G; Zhao, Gongbo; Schneider, Donald P; Brownstein, Joel R; Thomas, Daniel; Brinkmann, Jonathan V
2013-01-01
In the context of the study of the Integrated Sachs Wolfe effect (ISW), we construct a template of the projected density distribution up to $z\\simeq 0.7$ by using the Luminous Galaxies (LGs) from the Sloan Digital Sky Survey DR8. We use a photo-z catalogue trained with more than a hundred thousand galaxies from BOSS in the SDSS DR8 imaging area. We consider two different LG samples whose selection matches that of SDSS-III/BOSS: the LOWZ sample ($z\\in [0.15,0.5]$) and the CMASS sample ($z\\in[0.4,0.7]$). When building the LG density maps we use the information from star density, survey footprint, seeing conditions, sky emission, dust extinction and airmass to explore the impact of these artifacts on the two LG samples. In agreement with previous studies, we find that the CMASS sample is particularly sensitive to Galactic stars, which dominate the contribution to the auto-angular power spectrum below $\\ell=7$. Other potential systematics affect mostly the low multipole range ($\\ell\\in[2,7]$), but leave fluctuati...
METRICS DEVELOPMENT FOR PATENTS.
Veiga, Daniela Francescato; Ferreira, Lydia Masako
2015-01-01
To develop a proposal for metrics for patents to be applied in assessing the postgraduate programs of Medicine III - Capes. From the reading and analysis of the 2013 area documents of all the 48 areas of Capes, a proposal for metrics for patents was developed to be applied in Medicine III programs. Except for the areas Biotechnology, Food Science, Biological Sciences III, Physical Education, Engineering I, III and IV and Interdisciplinary, most areas do not adopt a scoring system for patents. The proposal developed was based on the criteria of Biotechnology, with adaptations. In general, it will be valued, in ascending order, the deposit, the granting and licensing/production. It will also be assigned higher scores to patents registered abroad and whenever there is a participation of students. This proposal can be applied to the item Intellectual Production of the evaluation form, in subsection Technical Production/Patents. The percentage of 10% for academic programs and 40% for Masters Professionals should be maintained. The program will be scored as Very Good when it reaches 400 points or over; Good, between 200 and 399 points; Regular, between 71 and 199 points; Weak up to 70 points; Insufficient, no punctuation. Desenvolver uma proposta de métricas para patentes a serem aplicadas na avaliação dos Programas de Pós-Graduação da Área Medicina III - Capes. A partir da leitura e análise dos documentos de área de 2013 de todas as 48 Áreas da Capes, desenvolveu-se uma proposta de métricas para patentes, a ser aplicada na avaliação dos programas da área. Constatou-se que, com exceção das áreas Biotecnologia, Ciência de Alimentos, Ciências Biológicas III, Educação Física, Engenharias I, III e IV e Interdisciplinar, a maioria não adota sistema de pontuação para patentes. A proposta desenvolvida baseou-se nos critérios da Biotecnologia, com adaptações. De uma forma geral, foi valorizado, em ordem crescente, o depósito, a concessão e o
2008-01-01
As Global Positioning Satellite (GPS) applications become more prevalent for land- and air-based vehicles, GPS applications for space vehicles will also increase. The Applied Technology Directorate of Kennedy Space Center (KSC) has developed a lightweight, low-cost GPS Metric Tracking Unit (GMTU), the first of two steps in developing a lightweight, low-cost Space-Based Tracking and Command Subsystem (STACS) designed to meet Range Safety's link margin and latency requirements for vehicle command and telemetry data. The goals of STACS are to improve Range Safety operations and expand tracking capabilities for space vehicles. STACS will track the vehicle, receive commands, and send telemetry data through the space-based asset, which will dramatically reduce dependence on ground-based assets. The other step was the Low-Cost Tracking and Data Relay Satellite System (TDRSS) Transceiver (LCT2), developed by the Wallops Flight Facility (WFF), which allows the vehicle to communicate with a geosynchronous relay satellite. Although the GMTU and LCT2 were independently implemented and tested, the design collaboration of KSC and WFF engineers allowed GMTU and LCT2 to be integrated into one enclosure, leading to the final STACS. In operation, GMTU needs only a radio frequency (RF) input from a GPS antenna and outputs position and velocity data to the vehicle through a serial or pulse code modulation (PCM) interface. GMTU includes one commercial GPS receiver board and a custom board, the Command and Telemetry Processor (CTP) developed by KSC. The CTP design is based on a field-programmable gate array (FPGA) with embedded processors to support GPS functions.
Sharp metric obstructions for quasi-Einstein metrics
Case, Jeffrey S
2011-01-01
Using the tractor calculus to study conformally warped manifolds, we adapt results of Gover and Nurowski to give sharp metric obstructions to the existence of quasi-Einstein metrics on suitably generic manifolds. We do this by introducing an analogue of the curvature tractor, itself the tractor analogue of the curvature of the Fefferman-Graham ambient metric. We then use these obstructions to produce a tensorial invariant which is polynomial in the Riemann curvature and its divergence, and which gives the desired obstruction. In particular, this leads to a generalization to arbitrary dimensions of an algorithm due to Bartnik and Tod for finding static metrics. We also explore the consequences of this work for gradient Ricci solitons, finding an obstruction to their existence on suitably generic manifolds, and observing an interesting similarity between the nonnegativity of the curvature tractor and Hamilton's matrix Harnack inequality.
More on effective composite metrics
Heisenberg, Lavinia
2015-07-01
In this work we study different classes of effective composite metrics proposed in the context of one-loop quantum corrections in bimetric gravity. For this purpose we consider contributions of the matter loops in the form of cosmological constants and potential terms yielding two types of effective composite metrics. This guarantees a nice behavior at the quantum level. However, the theoretical consistency at the classical level needs to be ensured additionally. It turns out that among all these possible couplings, only one unique effective metric survives these criteria at the classical level.
More on effective composite metrics
Heisenberg, Lavinia
2015-01-01
In this work we study different classes of effective composite metrics proposed in the context of one-loop quantum corrections in bimetric gravity. For this purpose we consider contributions of the matter loops in form of cosmological constants and potential terms yielding two types of effective composite metrics. This guarantees a nice behaviour at the quantum level. However, the theoretical consistency at the classical level needs to be ensured additionally. It turns out that among all these possible couplings only one unique effective metric survives this criteria at the classical level.
Generalized Painleve-Gullstrand metrics
Energy Technology Data Exchange (ETDEWEB)
Lin Chunyu [Department of Physics, National Cheng Kung University, Tainan 70101, Taiwan (China)], E-mail: l2891112@mail.ncku.edu.tw; Soo Chopin [Department of Physics, National Cheng Kung University, Tainan 70101, Taiwan (China)], E-mail: cpsoo@mail.ncku.edu.tw
2009-02-02
An obstruction to the implementation of spatially flat Painleve-Gullstrand (PG) slicings is demonstrated, and explicitly discussed for Reissner-Nordstroem and Schwarzschild-anti-deSitter spacetimes. Generalizations of PG slicings which are not spatially flat but which remain regular at the horizons are introduced. These metrics can be obtained from standard spherically symmetric metrics by physical Lorentz boosts. With these generalized PG metrics, problematic contributions to the imaginary part of the action in the Parikh-Wilczek derivation of Hawking radiation due to the obstruction can be avoided.
Daylight metrics and energy savings
Energy Technology Data Exchange (ETDEWEB)
Mardaljevic, John; Heschong, Lisa; Lee, Eleanor
2009-12-31
The drive towards sustainable, low-energy buildings has increased the need for simple, yet accurate methods to evaluate whether a daylit building meets minimum standards for energy and human comfort performance. Current metrics do not account for the temporal and spatial aspects of daylight, nor of occupants comfort or interventions. This paper reviews the historical basis of current compliance methods for achieving daylit buildings, proposes a technical basis for development of better metrics, and provides two case study examples to stimulate dialogue on how metrics can be applied in a practical, real-world context.
Conformal Patterson-Walker metrics
Hammerl, Matthias; Šilhan, Josef; Taghavi-Chabert, Arman; Žádník, Vojtěch
2016-01-01
The classical Patterson-Walker construction of a split-signature (pseudo-)Riemannian structure from a given torsion-free affine connection is generalized to a construction of a split-signature conformal structure from a given projective class of connections. A characterization of the induced structures is obtained. We achieve a complete description of Einstein metrics in the conformal class formed by the Patterson-Walker metric. Finally, we describe all symmetries of the conformal Patterson-Walker metric. In both cases we obtain descriptions in terms of geometric data on the original structure.
Udwadia-Hegde, Anaita; Hajirnis, Omkar
2017-01-01
Juvenile Tay-Sachs disease is rarer than other forms of Tay-Sachs disease and is usually seen in children between the age of 2 and 10 years. Pyrimethamine as a pharmacological chaperone was used to increase β-hexosaminidase A activity in this patient. We describe a patient with Tay-Sachs disease from the Indian population, a juvenile case who presented with developmental regression starting at the age of three, initially with motor followed by language regression. She is currently incapacitated with severe behavioral issues. This brief communication gives an insight into the efficacy of pharmacological chaperones. It also describes two unreported mutations in hexosaminidase A gene from the Indian population. After commencing Pyrimethamine, though initial benefits with increase in levels corresponded with briefly halting the motor regression, the observed increase was only transient and not associated with discernible beneficial neurological or psychiatric effects.
Zimmerman, Marianna
1975-01-01
Describes a classroom activity which involved sixth grade students in a learning situation including making ice cream, safety procedures in a science laboratory, calibrating a thermometer, using metric units of volume and mass. (EB)
A unifying process capability metric
Directory of Open Access Journals (Sweden)
John Jay Flaig
2009-07-01
Full Text Available A new economic approach to process capability assessment is presented, which differs from the commonly used engineering metrics. The proposed metric consists of two economic capability measures – the expected profit and the variation in profit of the process. This dual economic metric offers a number of significant advantages over other engineering or economic metrics used in process capability analysis. First, it is easy to understand and communicate. Second, it is based on a measure of total system performance. Third, it unifies the fraction nonconforming approach and the expected loss approach. Fourth, it reflects the underlying interest of management in knowing the expected financial performance of a process and its potential variation.
Zimmerman, Marianna
1975-01-01
Describes a classroom activity which involved sixth grade students in a learning situation including making ice cream, safety procedures in a science laboratory, calibrating a thermometer, using metric units of volume and mass. (EB)
Phantom metrics with Killing spinors
Directory of Open Access Journals (Sweden)
W.A. Sabra
2015-11-01
Full Text Available We study metric solutions of Einstein–anti-Maxwell theory admitting Killing spinors. The analogue of the IWP metric which admits a space-like Killing vector is found and is expressed in terms of a complex function satisfying the wave equation in flat (2+1-dimensional space–time. As examples, electric and magnetic Kasner spaces are constructed by allowing the solution to depend only on the time coordinate. Euclidean solutions are also presented.
Coverage Metrics for Model Checking
Penix, John; Visser, Willem; Norvig, Peter (Technical Monitor)
2001-01-01
When using model checking to verify programs in practice, it is not usually possible to achieve complete coverage of the system. In this position paper we describe ongoing research within the Automated Software Engineering group at NASA Ames on the use of test coverage metrics to measure partial coverage and provide heuristic guidance for program model checking. We are specifically interested in applying and developing coverage metrics for concurrent programs that might be used to support certification of next generation avionics software.
Cho, Nam Su; Yoo, Jae Hyun; Juh, Hyung Suk; Rhee, Yong Girl
2016-12-01
The purpose of this study was to compare the clinical results of isolated arthroscopic Bankart repair and those of arthroscopic Bankart repair with posterior capsulodesis for anterior shoulder instability with engaging Hill-Sachs lesions. Thirty-five shoulders that underwent isolated arthroscopic Bankart repair (Bankart group) and 37 shoulders that underwent arthroscopic Bankart repair with posterior capsulodesis (remplissage group) for anterior shoulder instability with engaging Hill-Sachs lesions were evaluated retrospectively. The mean age at the time of the surgery was 26.1 ± 7.0 years in the Bankart group and 24.8 ± 9.0 years in the remplissage group. At the final follow-up, the Rowe and UCLA scores significantly improved in both the Bankart and remplissage groups (P Bankart group and 8° ± 23° in the remplissage group (P = n.s. and P = 0.044, respectively). There was no decrease in muscle strength in either group. The recurrence rate was 25.7 % in the Bankart group and 5.4 % in the remplissage group (P = 0.022). Arthroscopic Bankart repair with posterior capsulodesis demonstrated good clinical outcomes with a low recurrence rate in the treatment for anterior shoulder instability with an engaging Hill-Sachs lesion. Although a limitation in external rotation was observed, there was no significant limitation of any other motion and no decrease in muscle strength after the remplissage procedure. Posterior capsulodesis alone for remplissage should be considered as a surgical technique that can replace the conventional method. Case-control study, Level III.
Candelas, Philip; McOrist, Jock
2016-01-01
Heterotic vacua of string theory are realised, at large radius, by a compact threefold with vanishing first Chern class together with a choice of stable holomorphic vector bundle. These form a wide class of potentially realistic four-dimensional vacua of string theory. Despite all their phenomenological promise, there is little understanding of the metric on the moduli space of these. What is sought is the analogue of special geometry for these vacua. The metric on the moduli space is important in phenomenology as it normalises D-terms and Yukawa couplings. It is also of interest in mathematics, since it generalises the metric, first found by Kobayashi, on the space of gauge field connections, to a more general context. Here we construct this metric, correct to first order in alpha', in two ways: first by postulating a metric that is invariant under background gauge transformations of the gauge field, and also by dimensionally reducing heterotic supergravity. These methods agree and the resulting metric is Ka...
Lew, Raelia M; Proos, Anne L; Burnett, Leslie; Delatycki, Martin; Bankier, Agnes; Fietz, Michael J
2012-12-10
To evaluate the outcomes of preconception screening of Jewish Australians for Tay Sachs disease (TSD) carrier status on Jewish TSD-affected births. Epidemiological observational study involving a complete retrospective audit of infantile and intermediate TSD cases diagnosed in Sydney and Melbourne between 1 January 1995 and 31 December 2011 (Royal Children's Hospital Melbourne; Pacific Laboratory Medicine Services, Pathology North, NSW Health Pathology, Sydney; Victorian Clinical Genetics Services, Melbourne; and SA Pathology, Adelaide), and carrier frequency among Jewish high school students attending schools participating in TSD screening programs over the same period. Jewish TSD carrier frequency; and expected versus observed Jewish TSD-affected births. The 2006 Census indicated that most of the total 88,826 Jewish Australians live in Melbourne (46%) and Sydney (40%). The 7,756 Jewish high school students screened for TSD in Sydney and Melbourne during the study period had a carrier frequency of one in 31 (3.26%; 95% CI, 2.89%-3.68%).The estimated expected number of TSD-affected births in Melbourne and Sydney in 1995-2011 was 4.1 for Jewish births and 7.4 for other births (a ratio of Jewish to non-Jewish births of 1:2). The actual number was 12 (four in Sydney and eight in Melbourne), of which two were Jewish (a ratio of Jewish to non-Jewish births of 1:5). This finding of fewer than expected Jewish TSD cases coincided with a period during which screening programs were operating. There have been no Jewish TSD-affected children born to parents who were screened previously. Community education, appreciation of autosomal recessive inheritance and genetic carrier screening before pregnancy are the likely factors in our finding of fewer than expected Jewish babies with TSD. Ongoing outcome monitoring must continue.
Characterization of inducible models of Tay-Sachs and related disease.
Sargeant, Timothy J; Drage, Deborah J; Wang, Susan; Apostolakis, Apostolos A; Cox, Timothy M; Cachón-González, M Begoña
2012-09-01
Tay-Sachs and Sandhoff diseases are lethal inborn errors of acid β-N-acetylhexosaminidase activity, characterized by lysosomal storage of GM2 ganglioside and related glycoconjugates in the nervous system. The molecular events that lead to irreversible neuronal injury accompanied by gliosis are unknown; but gene transfer, when undertaken before neurological signs are manifest, effectively rescues the acute neurodegenerative illness in Hexb-/- (Sandhoff) mice that lack β-hexosaminidases A and B. To define determinants of therapeutic efficacy and establish a dynamic experimental platform to systematically investigate cellular pathogenesis of GM2 gangliosidosis, we generated two inducible experimental models. Reversible transgenic expression of β-hexosaminidase directed by two promoters, mouse Hexb and human Synapsin 1 promoters, permitted progression of GM2 gangliosidosis in Sandhoff mice to be modified at pre-defined ages. A single auto-regulatory tetracycline-sensitive expression cassette controlled expression of transgenic Hexb in the brain of Hexb-/- mice and provided long-term rescue from the acute neuronopathic disorder, as well as the accompanying pathological storage of glycoconjugates and gliosis in most parts of the brain. Ultimately, late-onset brainstem and ventral spinal cord pathology occurred and was associated with increased tone in the limbs. Silencing transgenic Hexb expression in five-week-old mice induced stereotypic signs and progression of Sandhoff disease, including tremor, bradykinesia, and hind-limb paralysis. As in germline Hexb-/- mice, these neurodegenerative manifestations advanced rapidly, indicating that the pathogenesis and progression of GM2 gangliosidosis is not influenced by developmental events in the maturing nervous system.
The Late Integrated Sachs-Wolfe Effect and its detectability in galaxy-redshift surveys
Valencia-Díaz, D. R.; Muñoz-Cuartas, J. C.
2017-07-01
The late Integrated Sachs-Wolfe (ISW) effect is underwent by the Cosmic Microwave Background (CMB) photons due to the presence of the Large-Scale Structures (LSS) in an expanding Universe and can be measured through the temperature fluctuations of the CMB. In this work we use numerical simulations of structure formation to study the detectability of the ISW effect. Our method comprises the estimation of the density field through a Cloud-In-Cell mass assignment scheme. With the help of Fourier transforms we estimate the time derivative of the gravitational potential field in Fourier and in coordinate's space. Finally, this field is integrated numerically to know the ISW contribution. We study the time derivative of the potential in two approaches. First, an exact solution that makes use of the full velocity field. Second, a linear approximation related with the linear theory for the formation of LSS. We apply the method to three cosmological simulations. First, a box of 400 h-1 Mpc; second, the MultiDark1 simulation; third, the MultiDark-Plank simulation. For all cases we obtain coherent results with the expected in the literature for a ΛCDM cosmology: with the exact solution the temperature fluctuation is near the ± 30 μ K; the linear approximation shows a signal in the expected range of ± 20 μ K. This positive detection on simulations is important in order to know an expectation for the results we should obtain when working with observational data and will have important implications due to the lack of consensus about the detection of the ISW effect in previous works. Acknowledgements: This work was supported by Colciencias and Universidad de Antioquia, Convenio Beca-Pasantía Joven Investigador Convocatoria 645 de 2014.
Haghighi, Alireza; Rezazadeh, Jamileh; Shadmehri, Azam Ahmadi; Haghighi, Amirreza; Kornreich, Ruth; Desnick, Robert J
2011-09-01
The β-hexosaminidase A (HEXA) mutations in the first reported cases of infantile Tay-Sachs disease in the Persian population were identified in two unrelated consanguineous families. The clinical diagnoses of the affected infants were confirmed by their markedly deficient levels of HEXA activity in plasma or peripheral leukocytes. The specific causative mutation in each family was determined by sequencing the HEXA alleles in both sets of related parents. Two mutations were identified: c.1A>G (p.MIV), which obliterated the initiating methionine in codon 1, and c.1177C>T (p.R393X), which predicted a termination codon or nonsense mutation.
Osher, Etty; Fattal-Valevski, Aviva; Sagie, Liora; Urshanski, Nataly; Sagiv, Nadav; Peleg, Leah; Lerman-Sagie, Tally; Zimran, Ari; Elstein, Deborah; Navon, Ruth; Valevski, Avi; Stern, Naftali
2015-01-01
Background Late Onset Tay- Sachs disease (LOTS) is a rare neurodegenerative lysosomal storage disease which results from mutations in the gene encoding the α subunit (HEXA) of β-hexosaminidase enzyme (HexA). At the present time, no effective treatment exists for LOTS and other neurodegenerative diseases involving the central nerve system (CNS). Pyrimethamine (PMT) was previously shown to act as a HexA chaperone in human fibroblasts in vitro carrying some (e.g., αG269S), but not all LOTS-relat...
At least six different mutations in HEXA gene cause Tay-Sachs disease among the Turkish population.
Ozkara, H A; Navon, R
1998-11-01
Twenty-five Turkish infants with Tay-Sachs disease (TSD) have been diagnosed in the past 8 years. All are from consanguineous, nonrelated families. The present study deals with the molecular basis of six Turkish TSD patients from five unrelated families in which the parents were first cousins. The five mutations identified in this study were INS-5 G-->A, R393X, R137X, 12-bp deletion in exon 10, and G454D. The first three were reported in earlier studies, two in Turkish TSD infants and one in a French TSD infant.
Pathological alterations typical of human Tay-Sachs disease, in the retina of a deep-sea fish
Fishelson, L.; Delarea, Yacov; Galil, Bella S.
Micrographs of retinas from the deep-sea fish Cataetyx laticeps revealed visual cells containing membranous whorls in the ellipsoids of the inner segments resulting from stretching and modifications of the mitochondria membranes and their cristae. These pathological structures seem to be homologous to the whorls observed in retinas of human carriers of Tay-Sachs disease. This disease, a genetic disorder, is found in humans and some mammals. Our findings in fish suggest that the gene responsible can be found throughout the vertebrate evolutionary tree, possibly dormant in most taxa.
Ibragimov, N H; Wessels, E J H; Ellis, George F. R.; Ibragimov, Nail H.; Wessels, Ewald J. H.
2006-01-01
We carry out a Lie group analysis of the Sachs equations for a time-dependent axisymmetric non-rotating space-time in which the Ricci tensor vanishes. These equations, which are the first two members of the set of Newman-Penrose equations, define the characteristic initial-value problem for the space-time. We find a particular form for the initial data such that these equations admit a Lie symmetry, and so defines a geometrically special class of such spacetimes. These should additionally be of particular physical interest because of this special geometric feature.
Pérez de Arce,José; Gili,Francisca
2013-01-01
El sistema de clasificación de instrumentos musicales ideado por Curt Sachs y Erich Moritz von Horbonstel en 1914 es universalmente usado hasta hoy. En este artículo se analizan las razones de esta permanencia y se revisa en general la historia de los distintos criterios usados para clasificar los instrumentos musicales. Igualmente se explica, de acuerdo con nuestra experiencia, el porqué el sistema de Sachs-Hornbostel nos parece el más apropiado para la realidad americana, con énfasis en la ...
Projectively related metrics, Weyl nullity, and metric projectively invariant equations
Gover, A Rod
2015-01-01
A metric projective structure is a manifold equipped with the unparametrised geodesics of some pseudo-Riemannian metric. We make acomprehensive treatment of such structures in the case that there is a projective Weyl curvature nullity condition. The analysis is simplified by a fundamental and canonical 2-tensor invariant that we discover. It leads to a new canonical tractor connection for these geometries which is defined on a rank $(n+1)$-bundle. We show this connection is linked to the metrisability equations that govern the existence of metrics compatible with the structure. The fundamental 2-tensor also leads to a new class of invariant linear differential operators that are canonically associated to these geometries; included is a third equation studied by Gallot et al. We apply the results to study the metrisability equation, in the nullity setting described. We obtain strong local and global results on the nature of solutions and also on the nature of the geometries admitting such solutions, obtaining ...
Metrics for phylogenetic networks II: nodal and triplets metrics.
Cardona, Gabriel; Llabrés, Mercè; Rosselló, Francesc; Valiente, Gabriel
2009-01-01
The assessment of phylogenetic network reconstruction methods requires the ability to compare phylogenetic networks. This is the second in a series of papers devoted to the analysis and comparison of metrics for tree-child time consistent phylogenetic networks on the same set of taxa. In this paper, we generalize to phylogenetic networks two metrics that have already been introduced in the literature for phylogenetic trees: the nodal distance and the triplets distance. We prove that they are metrics on any class of tree-child time consistent phylogenetic networks on the same set of taxa, as well as some basic properties for them. To prove these results, we introduce a reduction/expansion procedure that can be used not only to establish properties of tree-child time consistent phylogenetic networks by induction, but also to generate all tree-child time consistent phylogenetic networks with a given number of leaves.
Energy Technology Data Exchange (ETDEWEB)
Enqvist, Kari [Physics Department, University of Helsinki, and Helsinki Institute of Physics, FIN-00014 Helsinki (Finland); Koivisto, Tomi [Institute for Theoretical Physics and Spinoza Institute, Leuvenlaan 4, 3584 CE Utrecht (Netherlands); Rigopoulos, Gerasimos, E-mail: kari.enqvist@helsinki.fi, E-mail: T.S.Koivisto@astro.uio.no, E-mail: rigopoulos@physik.rwth-aachen.de [Institut für Theoretische Teilchenphysik und Kosmologie, RWTH Aachen University, D-52056 Aachen (Germany)
2012-05-01
We consider inflation within the context of what is arguably the simplest non-metric extension of Einstein gravity. There non-metricity is described by a single graviscalar field with a non-minimal kinetic coupling to the inflaton field Ψ, parameterized by a single parameter γ. There is a simple equivalent description in terms of a massless field and an inflaton with a modified potential. We discuss the implications of non-metricity for chaotic inflation and find that it significantly alters the inflaton dynamics for field values Ψ∼>M{sub P}/γ, dramatically changing the qualitative behaviour in this regime. In the equivalent single-field description this is described as a cuspy potential that forms of barrier beyond which the inflation becomes a ghost field. This imposes an upper bound on the possible number of e-folds. For the simplest chaotic inflation models, the spectral index and the tensor-to-scalar ratio receive small corrections dependent on the non-metricity parameter. We also argue that significant post-inflationary non-metricity may be generated.
Lagrange Spaces with (γ,β-Metric
Directory of Open Access Journals (Sweden)
Suresh K. Shukla
2013-01-01
Full Text Available We study Lagrange spaces with (γ,β-metric, where γ is a cubic metric and β is a 1-form. We obtain fundamental metric tensor, its inverse, Euler-Lagrange equations, semispray coefficients, and canonical nonlinear connection for a Lagrange space endowed with a (γ,β-metric. Several other properties of such space are also discussed.
Energy Technology Data Exchange (ETDEWEB)
Mark, Brian L.; Mahuran, Don J.; Cherney, Maia M.; Zhao, Dalian; Knapp, Spencer; James, Michael N.G.
2010-12-01
In humans, two major {beta}-hexosaminidase isoenzymes exist: Hex A and Hex B. Hex A is a heterodimer of subunits {alpha} and {beta} (60% identity), whereas Hex B is a homodimer of {beta}-subunits. Interest in human {beta}-hexosaminidase stems from its association with Tay-Sachs and Sandhoff disease; these are prototypical lysosomal storage disorders resulting from the abnormal accumulation of G{sub M2}-ganglioside (G{sub M2}). Hex A degrades G{sub M2} by removing a terminal N-acetyl-D-galactosamine ({beta}-GalNAc) residue, and this activity requires the G{sub M2}-activator, a protein which solubilizes the ganglioside for presentation to Hex A. We present here the crystal structure of human Hex B, alone (2.4 {angstrom}) and in complex with the mechanistic inhibitors GalNAc-isofagomine (2.2 {angstrom}) or NAG-thiazoline (2.5 {angstrom}). From these, and the known X-ray structure of the G{sub M2}-activator, we have modeled Hex A in complex with the activator and ganglioside. Together, our crystallographic and modeling data demonstrate how {alpha} and {beta}-subunits dimerize to form either Hex A or Hex B, how these isoenzymes hydrolyze diverse substrates, and how many documented point mutations cause Sandhoff disease ({beta}-subunit mutations) and Tay-Sachs disease ({alpha}-subunit mutations).
Robertson, Stanley L
2016-01-01
Magnetic Eternally Collapsing Objects (MECO) have been proposed as the central engines of galactic black hole candidates (GBHC) and supermassive active galactic nuclei (AGN). Previous work has shown that their luminosities and spectral and timing characteristics are in good agreement with observations. These features and the formation of jets are generated primarily by the interactions of accretion disks with an intrinsically magnetic central MECO. The interaction of accretion disks with the anchored magnetic fields of the central objects permits a unified description of properties for GBHC, AGN, neutron stars in low mass x-ray binaries and dwarf novae systems. The previously published MECO models have been based on a quasistatic Schwarzschild metric of General Relativity; however, the only essential feature of this metric is its ability to produce extreme gravitational redshifts. For reasons discussed in this article, an alternative development based on a quasistatic exponential metric is considered here.
Complexity Metrics for Spreadsheet Models
Bregar, Andrej
2008-01-01
Several complexity metrics are described which are related to logic structure, data structure and size of spreadsheet models. They primarily concentrate on the dispersion of cell references and cell paths. Most metrics are newly defined, while some are adapted from traditional software engineering. Their purpose is the identification of cells which are liable to errors. In addition, they can be used to estimate the values of dependent process metrics, such as the development duration and effort, and especially to adjust the cell error rate in accordance with the contents of each individual cell, in order to accurately asses the reliability of a model. Finally, two conceptual constructs - the reference branching condition cell and the condition block - are discussed, aiming at improving the reliability, modifiability, auditability and comprehensibility of logical tests.
Complexity Metrics for Workflow Nets
DEFF Research Database (Denmark)
Lassen, Kristian Bisgaard; van der Aalst, Wil M.P.
2009-01-01
, etc. It seems obvious that the complexity of the model contributes to design errors and a lack of understanding. It is not easy to measure complexity, however. This paper presents three complexity metrics that have been implemented in the process analysis tool ProM. The metrics are defined...... analysts have difficulties grasping the dynamics implied by a process model. Recent empirical studies show that people make numerous errors when modeling complex business processes, e.g., about 20 percent of the EPCs in the SAP reference model have design flaws resulting in potential deadlocks, livelocks...... for a subclass of Petri nets named Workflow nets, but the results can easily be applied to other languages. To demonstrate the applicability of these metrics, we have applied our approach and tool to 262 relatively complex Protos models made in the context of various student projects. This allows us to validate...
Moduli spaces of riemannian metrics
Tuschmann, Wilderich
2015-01-01
This book studies certain spaces of Riemannian metrics on both compact and non-compact manifolds. These spaces are defined by various sign-based curvature conditions, with special attention paid to positive scalar curvature and non-negative sectional curvature, though we also consider positive Ricci and non-positive sectional curvature. If we form the quotient of such a space of metrics under the action of the diffeomorphism group (or possibly a subgroup) we obtain a moduli space. Understanding the topology of both the original space of metrics and the corresponding moduli space form the central theme of this book. For example, what can be said about the connectedness or the various homotopy groups of such spaces? We explore the major results in the area, but provide sufficient background so that a non-expert with a grounding in Riemannian geometry can access this growing area of research.
Rainbow metric from quantum gravity
Assaniousssi, Mehdi; Lewandowski, Jerzy
2014-01-01
In this letter, we describe a general mechanism for emergence of a rainbow metric from a quantum cosmological model. This idea is based on QFT on a quantum space-time. Under general assumptions, we discover that the quantum space-time on which the field propagates can be replaced by a classical space-time, whose metric depends explicitly on the energy of the field: as shown by an analysis of dispersion relations, quanta of different energy propagate on different metrics, similar to photons in a refractive material (hence the name "rainbow" used in the literature). In deriving this result, we do not consider any specific theory of quantum gravity: the qualitative behavior of high-energy particles on quantum space-time relies only on the assumption that the quantum space-time is described by a wave-function $\\Psi_o$ in a Hilbert space $\\mathcal{H}_G$.
Directory of Open Access Journals (Sweden)
Bessem Samet
2013-01-01
Full Text Available In 2005, Mustafa and Sims (2006 introduced and studied a new class of generalized metric spaces, which are called G-metric spaces, as a generalization of metric spaces. We establish some useful propositions to show that many fixed point theorems on (nonsymmetric G-metric spaces given recently by many authors follow directly from well-known theorems on metric spaces. Our technique can be easily extended to other results as shown in application.
S-curvature of isotropic Berwald metrics
Institute of Scientific and Technical Information of China (English)
Akbar TAYEBI; Mehdi RAFIE-RAD
2008-01-01
Isotropic Berwald metrics are as a generalization of Berwald metrics. Shen proved that every Berwald metric is of vanishing S-curvature. In this paper, we generalize this fact and prove that every isotropic Berwald metric is of isotropic S-curvature. Let F = α + β be a Randers metric of isotropic Berwald curvature. Then it corresponds to a conformal vector field through navigation representation.
DLA Energy Biofuel Feedstock Metrics Study
2012-12-11
moderately/highly in- vasive Metric 2: Genetically modified organism ( GMO ) hazard, Yes/No and Hazard Category Metric 3: Species hybridization...4– biofuel distribution Stage # 5– biofuel use Metric 1: State inva- siveness ranking Yes Minimal Minimal No No Metric 2: GMO hazard Yes...may utilize GMO microbial or microalgae species across the applicable biofuel life cycles (stages 1–3). The following consequence Metrics 4–6 then
Hernández-Monteagudo, Carlos; Ross, Ashley J.; Cuesta, Antonio; Génova-Santos, Ricardo; Xia, Jun-Qing; Prada, Francisco; Rossi, Graziano; Neyrinck, Mark; Viel, Matteo; Rubiño-Martin, Jose-Alberto; Scóccola, Claudia G.; Zhao, Gongbo; Schneider, Donald P.; Brownstein, Joel R.; Thomas, Daniel; Brinkmann, Jonathan V.
2014-02-01
In the context of the study of the integrated Sachs-Wolfe (ISW) effect, we construct a template of the projected density distribution up to redshift z ≃ 0.7 by using the luminous galaxies (LGs) from the Sloan Digital Sky Survey (SDSS) Data Release 8 (DR8). We use a photometric redshift catalogue trained with more than a hundred thousand galaxies from the Baryon Oscillation Spectroscopic Survey (BOSS) in the SDSS DR8 imaging area covering nearly one-quarter of the sky. We consider two different LG samples whose selection matches that of SDSS-III/BOSS: the low-redshift sample (LOWZ, z ∈ [0.15, 0.5]) and the constant mass sample (CMASS, z ∈ [0.4, 0.7]). When building the galaxy angular density templates we use the information from star density, survey footprint, seeing conditions, sky emission, dust extinction and airmass to explore the impact of these artefacts on each of the two LG samples. In agreement with previous studies, we find that the CMASS sample is particularly sensitive to Galactic stars, which dominate the contribution to the auto-angular power spectrum below ℓ = 7. Other potential systematics affect mostly the very low multipole range (ℓ ∈ [2, 7]), but leave fluctuations on smaller scales practically unchanged. The resulting angular power spectra in the multipole range ℓ ∈ [2, 100] for the LOWZ, CMASS and LOWZ+CMASS samples are compatible with linear Λ cold dark matter (ΛCDM) expectations and constant bias values of b = 1.98 ± 0.11, 2.08 ± 0.14 and 1.88 ± 0.11, respectively, with no traces of non-Gaussianity signatures, i.e. f_NL^local=59± 75 at 95 per cent confidence level for the full LOWZ+CMASS sample in the multipole range ℓ ∈ [4, 100]. After cross-correlating Wilkinson Microwave Anisotropy Probe 9-year data with the LOWZ+CMASS LG projected density field, the ISW signal is detected at the level of 1.62-1.69σ. While this result is in close agreement with theoretical expectations and predictions from realistic Monte Carlo
Thermodynamic Metrics and Optimal Paths
Energy Technology Data Exchange (ETDEWEB)
Sivak, David; Crooks, Gavin
2012-05-08
A fundamental problem in modern thermodynamics is how a molecular-scale machine performs useful work, while operating away from thermal equilibrium without excessive dissipation. To this end, we derive a friction tensor that induces a Riemannian manifold on the space of thermodynamic states. Within the linear-response regime, this metric structure controls the dissipation of finite-time transformations, and bestows optimal protocols with many useful properties. We discuss the connection to the existing thermodynamic length formalism, and demonstrate the utility of this metric by solving for optimal control parameter protocols in a simple nonequilibrium model.
Separable metrics and radiating stars
Indian Academy of Sciences (India)
G Z ABEBE; S D MAHARAJ
2017-01-01
We study the junction condition relating the pressure to heat flux at the boundary of an accelerating and expanding spherically symmetric radiating star. We transform the junction condition to an ordinary differential equation by making a separability assumption on the metric functions in the space–time variables. The condition of separability on the metric functions yields several new exact solutions. A class of shear-free models is found which contains a linear equation of state and generalizes a previously obtained model. Four new shearing models are obtained; all the gravitational potentials can be written explicitly. A brief physical analysis indicates that the matter variables are well behaved.
Einstein metrics in projective geometry
Cap, A; Macbeth, H R
2012-01-01
It is well known that pseudo-Riemannian metrics in the projective class of a given torsion free affine connection can be obtained from (and are equivalent to) the solutions of a certain overdetermined projectively invariant differential equation. This equation is a special case of a so-called first BGG equation. The general theory of such equations singles out a subclass of so-called normal solutions. We prove that non-degerate normal solutions are equivalent to pseudo-Riemannian Einstein metrics in the projective class and observe that this connects to natural projective extensions of the Einstein condition.
Complexity Metrics for Workflow Nets
DEFF Research Database (Denmark)
Lassen, Kristian Bisgaard; van der Aalst, Wil M.P.
2009-01-01
Process modeling languages such as EPCs, BPMN, flow charts, UML activity diagrams, Petri nets, etc.\\ are used to model business processes and to configure process-aware information systems. It is known that users have problems understanding these diagrams. In fact, even process engineers and system......, etc. It seems obvious that the complexity of the model contributes to design errors and a lack of understanding. It is not easy to measure complexity, however. This paper presents three complexity metrics that have been implemented in the process analysis tool ProM. The metrics are defined...
The flexibility of optical metrics
Bittencourt, Eduardo; Smolyaninov, Igor; Smolyaninova, Vera N
2015-01-01
We firstly revisit the importance, naturalness and limitations of the so-called optical metrics for describing the propagation of light rays in the limit of geometric optics. We then exemplify their flexibility and nontriviality in some nonlinear material media and in the context of nonlinear theories of the electromagnetism, both underlain by curved backgrounds, where optical metrics could be flat and impermeable membranes only to photons could be conceived, respectively. Finally, we underline and discuss the relevance and potential applications of our analyses in a broad sense, ranging from material media to compact astrophysical systems.
The Extended Edit Distance Metric
Fuad, Muhammad Marwan Muhammad
2007-01-01
Similarity search is an important problem in information retrieval. This similarity is based on a distance. Symbolic representation of time series has attracted many researchers recently, since it reduces the dimensionality of these high dimensional data objects. We propose a new distance metric that is applied to symbolic data objects and we test it on time series data bases in a classification task. We compare it to other distances that are well known in the literature for symbolic data objects. We also prove, mathematically, that our distance is metric.
Performance Metrics for Haptic Interfaces
Samur, Evren
2012-01-01
Haptics technology is being used more and more in different applications, such as in computer games for increased immersion, in surgical simulators to create a realistic environment for training of surgeons, in surgical robotics due to safety issues and in mobile phones to provide feedback from user action. The existence of these applications highlights a clear need to understand performance metrics for haptic interfaces and their implications on device design, use and application. Performance Metrics for Haptic Interfaces aims at meeting this need by establishing standard practices for the ev
Phase-Space Noncommutative Quantum Cosmology
Bastos, Catarina; Dias, Nuno Costa; Prata, João Nuno
2007-01-01
We present a noncommutative extension of Quantum Cosmology and study the Kantowski-Sachs (KS) cosmological model requiring that the two scale factors of the KS metric, the coordinates of the system, and their conjugate canonical momenta do not commute. Through the ADM formalism, we obtain the Wheeler-DeWitt (WDW) equation for the noncommutative system. The Seiberg-Witten map is used to transform the noncommutative equation into a commutative one, i.e. into an equation with commutative variables, which depend on the noncommutative parameters, $\\theta$ and $\\eta$. Numerical solutions are found both for the classical and the quantum formulations of the system. These solutions are used to characterize the dynamics and the state of the universe. From the classical solutions we obtain the behavior of quantities such as the volume expansion, the shear and the characteristic volume. However the analysis of these quantities does not lead to any restriction on the value of the noncommutative parameters, $\\theta$ and $\\...
Danila, Bogdan; Lobo, Francisco S N; Mak, M K
2016-01-01
We consider the internal structure and the physical properties of specific classes of neutron, quark and Bose-Einstein Condensate stars in the hybrid metric-Palatini gravity theory, which is a combination of the metric and Palatini $f(R)$ formalisms. The theory is very successful in accounting for the observed phenomenology, since it unifies local constraints at the Solar System level and the late-time cosmic acceleration, even if the scalar field is very light. We derive the equilibrium equations for a spherically symmetric configuration (mass continuity and Tolman-Oppenheimer-Volkoff) in the framework of hybrid metric-Palatini theory, and we investigate their solutions numerically for different equations of state of neutron and quark matter, by adopting for the scalar field potential a Higgs-type form. Stellar models, described by the stiff fluid, radiation-like, the bag model and the Bose-Einstein Condensate equations of state are explicitly constructed in both General Relativity and hybrid metric-Palatini...
Ulicny, Brian; Baclawski, Ken; Magnus, Amy
2007-04-01
Blogs represent an important new arena for knowledge discovery in open source intelligence gathering. Bloggers are a vast network of human (and sometimes non-human) information sources monitoring important local and global events, and other blogs, for items of interest upon which they comment. Increasingly, issues erupt from the blog world and into the real world. In order to monitor blogging about important events, we must develop models and metrics that represent blogs correctly. The structure of blogs requires new techniques for evaluating such metrics as the relevance, specificity, credibility and timeliness of blog entries. Techniques that have been developed for standard information retrieval purposes (e.g. Google's PageRank) are suboptimal when applied to blogs because of their high degree of exophoricity, quotation, brevity, and rapidity of update. In this paper, we offer new metrics related for blog entry relevance, specificity, timeliness and credibility that we are implementing in a blog search and analysis tool for international blogs. This tools utilizes new blog-specific metrics and techniques for extracting the necessary information from blog entries automatically, using some shallow natural language processing techniques supported by background knowledge captured in domain-specific ontologies.
Socio-technical security metrics
Gollmann, D.; Herley, C.; Koenig, V.; Pieters, W.; Sasse, M.A.
2015-01-01
Report from Dagstuhl seminar 14491. This report documents the program and the outcomes of Dagstuhl Seminar 14491 “Socio-Technical Security Metrics”. In the domain of safety, metrics inform many decisions, from the height of new dikes to the design of nuclear plants. We can state, for example, that t
Leading Gainful Employment Metric Reporting
Powers, Kristina; MacPherson, Derek
2016-01-01
This chapter will address the importance of intercampus involvement in reporting of gainful employment student-level data that will be used in the calculation of gainful employment metrics by the U.S. Department of Education. The authors will discuss why building relationships within the institution is critical for effective gainful employment…
Strong metric dimension: A survey
Directory of Open Access Journals (Sweden)
Kratica Jozef
2014-01-01
Full Text Available The strong metric dimension has been a subject of considerable amount of research in recent years. This survey describes the related development by bringing together theoretical results and computational approaches, and places the recent results within their historical and scientific framework. [Projekat Ministarstva nauke Republike Srbije, br. 174010 i br. 174033
On a Schwarzschild like metric
Anastasiei, M
2011-01-01
In this short Note we would like to bring into the attention of people working in General Relativity a Schwarzschild like metric found by Professor Cleopatra Mociu\\c{t}chi in sixties. It was obtained by the A. Sommerfeld reasoning from his treatise "Elektrodynamik" but using instead of the energy conserving law from the classical Physics, the relativistic energy conserving law.
Miklyaeva, Elena I; Dong, Weijia; Bureau, Alexandre; Fattahie, Roya; Xu, Yongqin; Su, Meng; Fick, Gordon H; Huang, Jing-Qi; Igdoura, Suleiman; Hanai, Nobuo; Gravel, Roy A
2004-03-19
Tay-Sachs disease is an autosomal recessive neurodegenerative disease resulting from a block in the hydrolysis of GM2 ganglioside, an intermediate in ganglioside catabolism. The mouse model of Tay-Sachs disease (Hexa -/-) has been described as behaviorally indistinguishable from wild type until at least 1 year of age due to a sialidase-mediated bypass of the metabolic defect that reduces the rate of GM2 ganglioside accumulation. In this study, we have followed our mouse model to over 2 years of age and have documented a significant disease phenotype that is reminiscent of the late onset, chronic form of human Tay-Sachs disease. Onset occurs at 11-12 months of age and progresses slowly, in parallel with increasing storage of GM2 ganglioside. The disease is characterized by hind limb spasticity, weight loss, tremors, abnormal posture with lordosis, possible visual impairment, and, late in the disease, muscle weakness, clasping of the limbs, and myoclonic twitches of the head. Immunodetection of GM2 ganglioside showed that storage varies widely in different regions, but is most intense in pyriform cortex, hippocampus (CA3 field, subiculum), amygdala, hypothalamus (paraventricular supraoptic, ventromedial and arcuate nuclei, and mammilary body), and the somatosensory cortex (layer V) in 1- to 2-year-old mutant mice. We suggest that the Tay-Sachs mouse model is a phenotypically valid model of disease and may provide for a reliable indicator of the impact of therapeutic strategies, in particular geared to the late onset, chronic form of human Tay-Sachs disease.
Colaianni, Alessandra; Chandrasekharan, Subhashini; Cook-Deegan, Robert
2010-04-01
Genetic testing for Tay-Sachs and Canavan disease is particularly important for Ashkenazi Jews, because both conditions are more frequent in that population. This comparative case study was possible because of different patenting and licensing practices. The role of DNA testing differs between Tay-Sachs and Canavan diseases. The first-line screening test for Tay-Sachs remains an enzyme activity test rather than genotyping. Genotyping is used for preimplantation diagnosis and confirmatory testing. In contrast, DNA-based testing is the basis for Canavan screening and diagnosis. The HEXA gene for Tay-Sachs was cloned at the National Institutes of Health, and the gene was patented but has not been licensed. The ASPA gene for Canavan disease was cloned and patented by Miami Children's Hospital. Miami Children's Hospital did not inform family members and patient groups that had contributed to the gene discovery that it was applying for a patent, and pursued restrictive licensing practices when a patent issued in 1997. This led to intense controversy, litigation, and a sealed, nonpublic 2003 settlement that apparently allowed for nonexclusive licensing. A survey of laboratories revealed a possible price premium for ASPA testing, with per-unit costs higher than for other genetic tests in the Secretary's Advisory Committee on Genetics, Health, and Society case studies. The main conclusion from comparing genetic testing for Tay-Sachs and Canavan diseases, however, is that patenting and licensing conducted without communication with patients and advocates cause mistrust and can lead to controversy and litigation, a negative model to contrast with the positive model of patenting and licensing for genetic testing of cystic fibrosis.
Area metric gravity and accelerating cosmology
Punzi, R; Wohlfarth, M N R; Punzi, Raffaele; Schuller, Frederic P.; Wohlfarth, Mattias N.R.
2007-01-01
Area metric manifolds emerge as effective classical backgrounds in quantum string theory and quantum gauge theory, and present a true generalization of metric geometry. Here, we consider area metric manifolds in their own right, and develop in detail the foundations of area metric differential geometry. Based on the construction of an area metric curvature scalar, which reduces in the metric-induced case to the Ricci scalar, we re-interpret the Einstein-Hilbert action as dynamics for an area metric spacetime. In contrast to modifications of general relativity based on metric geometry, no continuous deformation scale needs to be introduced; the extension to area geometry is purely structural and thus rigid. We present an intriguing prediction of area metric gravity: without dark energy or fine-tuning, the late universe exhibits a small acceleration.
Length spectra and degeneration of flat metrics
Duchin, Moon; Rafi, Kasra
2009-01-01
In this paper we consider flat metrics (semi-translation structures) on surfaces of finite type. There are two main results. The first is a complete description of when a set of simple closed curves is spectrally rigid, that is, when the length vector determines a metric among the class of flat metrics. Secondly, we give an embedding into the space of geodesic currents and use this to get a boundary for the space of flat metrics. The geometric interpretation is that flat metrics degenerate to "mixed structures" on the surface: part flat metric and part measured foliation.
Nadathur, Seshadri
2016-01-01
We present a new method for detection of the integrated Sachs-Wolfe (ISW) imprints of cosmic superstructures on the cosmic microwave background, based on a matched filtering approach. The expected signal-to-noise ratio for this method is comparable to that obtained from the full cross-correlation, and unlike other stacked filtering techniques it is not subject to an a posteriori bias. We apply this method to Planck CMB data using voids and superclusters identified in the CMASS galaxy data from the Sloan Digital Sky Survey Data Release 12, and measure the ISW amplitude to be $A_\\mathrm{ISW}=1.64\\pm0.53$ relative to the $\\Lambda$CDM expectation, corresponding to a $3.1\\sigma$ detection. In contrast to some previous measurements of the ISW effect of superstructures, our result is in agreement with the $\\Lambda$CDM model.
Generation of HEXA-deficient hiPSCs from fibroblasts of a Tay-Sachs disease patient.
Liu, Zhong; Zhao, Rui
2016-09-01
Human iPSC line TSD-01-hiPSC was generated from fibroblasts of a patient with infantile Tay-Sachs disease (TSD). The patient is compound heterozygous at the HEXA gene by carrying a 1278insTATC allele and an IVS12+1G>C allele. STEMCCA lentivirus, which expresses OCT4, SOX2, KLF4, and c-MYC from a polycistronic transcript, were used for reprogramming. TSD-01-hiPSC express pluripotency markers such as OCT4, SOX2, NANOG, Tra-1-60, and alkaline phosphatase, and can differentiate into tissues from all the three embryonic germ layers. This TSD patient-derived hiPSC line may serve as a valuable in vitro tool for disease modeling and drug test.
Generation of HEXA-deficient hiPSCs from fibroblasts of a Tay-Sachs disease patient
Directory of Open Access Journals (Sweden)
Zhong Liu
2016-09-01
Full Text Available Human iPSC line TSD-01-hiPSC was generated from fibroblasts of a patient with infantile Tay-Sachs disease (TSD. The patient is compound heterozygous at the HEXA gene by carrying a 1278insTATC allele and an IVS12+1G>C allele. STEMCCA lentivirus, which expresses OCT4, SOX2, KLF4, and c-MYC from a polycistronic transcript, were used for reprogramming. TSD-01-hiPSC express pluripotency markers such as OCT4, SOX2, NANOG, Tra-1-60, and alkaline phosphatase, and can differentiate into tissues from all the three embryonic germ layers. This TSD patient-derived hiPSC line may serve as a valuable in vitro tool for disease modeling and drug test.
The escape velocity and Schwarzschild metric
Murzagalieva, A G; Murzagaliev, G Z
2002-01-01
The escape velocity value in the terms of general relativity by means Schwarzschild metric is provided to make of the motion equation with Friedman cosmological model behavior build in the terms of Robertson-Worker metric. (author)
Security Metrics in Industrial Control Systems
Collier, Zachary A; Ganin, Alexander A; Kott, Alex; Linkov, Igor
2015-01-01
Risk is the best known and perhaps the best studied example within a much broader class of cyber security metrics. However, risk is not the only possible cyber security metric. Other metrics such as resilience can exist and could be potentially very valuable to defenders of ICS systems. Often, metrics are defined as measurable properties of a system that quantify the degree to which objectives of the system are achieved. Metrics can provide cyber defenders of an ICS with critical insights regarding the system. Metrics are generally acquired by analyzing relevant attributes of that system. In terms of cyber security metrics, ICSs tend to have unique features: in many cases, these systems are older technologies that were designed for functionality rather than security. They are also extremely diverse systems that have different requirements and objectives. Therefore, metrics for ICSs must be tailored to a diverse group of systems with many features and perform many different functions. In this chapter, we first...
Dimension of the boundary in different metrics
Klén, Riku
2010-01-01
On domains $\\Omega\\subset\\R^n$, we consider metrics induced by continuous densities $\\rho\\colon\\Omega\\rightarrow(0,\\infty)$ and study the Hausdorff and packing dimensions of the boundary of $\\Omega$ with respect to these metrics.
Garcia, Grant H; Park, Min Jung; Zhang, Clare; Kelly, John D; Huffman, G Russell
2015-07-01
There is little comparative long-term clinical data comparing Bankart repair alone to the addition of remplissage. Our purpose was to compare results of patients with significant humeral head lesions and who underwent either isolated arthroscopic Bankart repair or remplissage. This is a retrospective cohort study of 14 isolated arthroscopic Bankart and 10 remplissage repairs all with large engaging Hill-Sachs (HS) lesions. Average follow-up was 40.72 months (26.3-51.1) in the Bankart group and 31.55 months (24.1-39.9) in the remplissage group. Surgical failure was defined as a dislocation or subluxation. Groups were matched on handedness, age within 3 years, and HS lesion size. Glenoid bone loss and HS size were measured on MRI. Additionally, WOSI and DASH scores were obtained. The average age at surgery was 26.0 years (17.8-41.1) of the isolated Bankart patient and 24.4 years (16.4-38.3) in the remplissage group. The average HS lesion volume was 310.22 mm(3) in the Bankart group and 283.79 mm(3) in the remplissage group. The failure rate for the Bankart group was 8 out of 14 patients (57.14%). For the remplissage group, the failure rate was 2 out of 10 patients (20.0%). Average WOSI scores were 73.72 in the Bankart group and 79.54 in the remplissage group. For DASH scores, the average Disability/Symptoms Scores were 16.23 for the Bankart group and 12.05 for the remplissage patients. In comparison to isolated Bankart repair, remplissage was a superior option for recurrent instability patients with large Hill-Sachs lesions as seen by diminished failure rates and improved outcome scores.
Directory of Open Access Journals (Sweden)
Parvaneh KARIMZADEH
2014-07-01
Full Text Available How to Cite This Article: Karimzadeh P, Jafari N, Nejad Biglari H, Jabbeh Dari S, Ahmad Abadi F, Alaee MR, Nemati H, Saket S,Tonekaboni SH, Taghdiri MM, Ghofrani M. GM2-Gangliosidosis (Sandhoff and Tay Sachs disease: Diagnosis and Neuroimaging Findings (An Iranian Pediatric Case Series Iran J Child Neurol. 2014 Summer;8(3: 55-60. AbstractObjectiveGM2-Gangliosidosis disease is a rare autosomal recessive genetic disorder that includes two disorders (Tay–Sachs and Sandhoff disease.These disorders cause a progressive deterioration of nerve cells and inherited deficiency in creatinghexosaminidases A, B, and AB.Materials & MethodsPatients who were diagnosed withGM2-Gangliosidosis in the Neurology Department of Mofid Children’s Hospital in Tehran, Iran from October 2009 to February 2014were included in our study. The disorder was confirmed by neurometabolic and enzyme level detection of hexosaminidases A, B, and ABin reference to Wagnester Laboratory in Germany. We assessed age, gender, past medical history, developmental status, clinical manifestations, and neuroimaging findings of 9 patients with Sandhoff disease and 9 with Tay Sachs disease.Results83% of our patients were the offspring of consanguineous marriages. All of them had a developmental disorder as a chief complaint.38%of patients had a history of developmental delay or regression and 22% hadseizures. The patients with Sandhoff and Tay Sachs disease were followed for approximately 5 years and the follow-up showed all patients were bedridden or had expired due to refractory seizures, pneumonia aspiration, or swallowingdisorders.Neuro-imaging findings included bilateral thalamic involvement, brain atrophy, and hypo myelination in near half of our patients (48%. ConclusionAccording to the results of this study, we suggest that cherry-red spots, hyperacusis, refractory seizures, and relative parents in children with developmental delay and/or regression should be considered
Hybrid metric-Palatini gravity
Capozziello, Salvatore; Koivisto, Tomi S; Lobo, Francisco S N; Olmo, Gonzalo J
2015-01-01
Recently, the phenomenology of f(R) gravity has been scrutinized motivated by the possibility to account for the self-accelerated cosmic expansion without invoking dark energy sources. Besides, this kind of modified gravity is capable of addressing the dynamics of several self-gravitating systems alternatively to the presence of dark matter. It has been established that both metric and Palatini versions of these theories have interesting features but also manifest severe and different downsides. A hybrid combination of theories, containing elements from both these two formalisms, turns out to be also very successful accounting for the observed phenomenology and is able to avoid some drawbacks of the original approaches. This article reviews the formulation of this hybrid metric-Palatini approach and its main achievements in passing the local tests and in applications to astrophysical and cosmological scenarios, where it provides a unified approach to the problems of dark energy and dark matter.
Hofer's metrics and boundary depth
Usher, Michael
2011-01-01
We show that if (M,\\omega) is a closed symplectic manifold which admits a nontrivial Hamiltonian vector field all of whose contractible closed orbits are constant, then Hofer's metric on the group of Hamiltonian diffeomorphisms of (M,\\omega) has infinite diameter, and indeed admits infinite-dimensional quasi-isometrically embedded normed vector spaces. A similar conclusion applies to Hofer's metric on various spaces of Lagrangian submanifolds, including those Hamiltonian-isotopic to the diagonal in M x M when M satisfies the above dynamical condition. To prove this, we use the properties of a Floer-theoretic quantity called the boundary depth, which measures the nontriviality of the boundary operator on the Floer complex in a way that encodes robust symplectic-topological information.
Projective Compactifications and Einstein metrics
Cap, Andreas
2013-01-01
For complete affine manifolds we introduce a definition of compactification based on the projective differential geometry (i.e.\\ geodesic path data) of the given connection. The definition of projective compactness involves a real parameter $\\alpha$ called the order of projective compactness. For volume preserving connections, this order is captured by a notion of volume asymptotics that we define. These ideas apply to complete pseudo-Riemannian spaces, via the Levi-Civita connection, and thus provide a notion of compactification alternative to conformal compactification. For each order $\\alpha$, we provide an asymptotic form of a metric which is sufficient for projective compactness of the given order, thus also providing many local examples. Distinguished classes of projectively compactified geometries of orders one and two are associated with Ricci-flat connections and non--Ricci--flat Einstein metrics, respectively. Conversely, these geometric conditions are shown to force the indicated order of projectiv...
Quality Metrics in Inpatient Neurology.
Dhand, Amar
2015-12-01
Quality of care in the context of inpatient neurology is the standard of performance by neurologists and the hospital system as measured against ideal models of care. There are growing regulatory pressures to define health care value through concrete quantifiable metrics linked to reimbursement. Theoretical models of quality acknowledge its multimodal character with quantitative and qualitative dimensions. For example, the Donabedian model distils quality as a phenomenon of three interconnected domains, structure-process-outcome, with each domain mutually influential. The actual measurement of quality may be implicit, as in peer review in morbidity and mortality rounds, or explicit, in which criteria are prespecified and systemized before assessment. As a practical contribution, in this article a set of candidate quality indicators for inpatient neurology based on an updated review of treatment guidelines is proposed. These quality indicators may serve as an initial blueprint for explicit quality metrics long overdue for inpatient neurology.
Marketing metrics for medical practices.
Zahaluk, David; Baum, Neil
2012-01-01
There's a saying by John Wanamaker who pontificated, "Half the money I spend on advertising is wasted; the trouble is, I don't know which half". Today you have opportunities to determine which parts of your marketing efforts are effective and what is wasted. However, you have to measure your marketing results. This article will discuss marketing metrics and how to use them to get the best bang for your marketing buck.
Multi-Metric Sustainability Analysis
Energy Technology Data Exchange (ETDEWEB)
Cowlin, Shannon [National Renewable Energy Lab. (NREL), Golden, CO (United States); Heimiller, Donna [National Renewable Energy Lab. (NREL), Golden, CO (United States); Macknick, Jordan [National Renewable Energy Lab. (NREL), Golden, CO (United States); Mann, Margaret [National Renewable Energy Lab. (NREL), Golden, CO (United States); Pless, Jacquelyn [National Renewable Energy Lab. (NREL), Golden, CO (United States); Munoz, David [Colorado School of Mines, Golden, CO (United States)
2014-12-01
A readily accessible framework that allows for evaluating impacts and comparing tradeoffs among factors in energy policy, expansion planning, and investment decision making is lacking. Recognizing this, the Joint Institute for Strategic Energy Analysis (JISEA) funded an exploration of multi-metric sustainability analysis (MMSA) to provide energy decision makers with a means to make more comprehensive comparisons of energy technologies. The resulting MMSA tool lets decision makers simultaneously compare technologies and potential deployment locations.
Toktarbay, Saken
2015-01-01
We present a stationary generalization of the static $q-$metric, the simplest generalization of the Schwarzschild solution that contains a quadrupole parameter. It possesses three independent parameters that are related to the mass, quadrupole moment and angular momentum. We investigate the geometric and physical properties of this exact solution of Einstein's vacuum equations, and show that it can be used to describe the exterior gravitational field of rotating, axially symmetric, compact objects.
Balanced metrics on Hartogs domains
Loi, Andrea
2010-01-01
An n-dimensional strictly pseudoconvex Hartogs domain $D_F$ can be equipped with a natural Kaehler metric g_F. In this paper we prove that if m_0g_F is balanced for a given positive integer m_0 then m_0>n and (D_F, g_F) is holomorphically isometric to an open subset of the n-dimensional complex hyperbolic space.
Extremal almost-Kahler metrics
Lejmi, Mehdi
2009-01-01
We generalize the notion of the Futaki invariant and extremal vector field to the general almost-Kahler case and we prove the periodicity of the extremal vector field when the symplectic form represents an integral cohomology class modulo torsion. We give also an explicit formula of the hermitian scalar curvature which allows us to obtain examples of non-integrable extremal almost-Kahler metrics saturating LeBrun's estimates.
Sensory Metrics of Neuromechanical Trust.
Softky, William; Benford, Criscillia
2017-09-01
Today digital sources supply a historically unprecedented component of human sensorimotor data, the consumption of which is correlated with poorly understood maladies such as Internet addiction disorder and Internet gaming disorder. Because both natural and digital sensorimotor data share common mathematical descriptions, one can quantify our informational sensorimotor needs using the signal processing metrics of entropy, noise, dimensionality, continuity, latency, and bandwidth. Such metrics describe in neutral terms the informational diet human brains require to self-calibrate, allowing individuals to maintain trusting relationships. With these metrics, we define the trust humans experience using the mathematical language of computational models, that is, as a primitive statistical algorithm processing finely grained sensorimotor data from neuromechanical interaction. This definition of neuromechanical trust implies that artificial sensorimotor inputs and interactions that attract low-level attention through frequent discontinuities and enhanced coherence will decalibrate a brain's representation of its world over the long term by violating the implicit statistical contract for which self-calibration evolved. Our hypersimplified mathematical understanding of human sensorimotor processing as multiscale, continuous-time vibratory interaction allows equally broad-brush descriptions of failure modes and solutions. For example, we model addiction in general as the result of homeostatic regulation gone awry in novel environments (sign reversal) and digital dependency as a sub-case in which the decalibration caused by digital sensorimotor data spurs yet more consumption of them. We predict that institutions can use these sensorimotor metrics to quantify media richness to improve employee well-being; that dyads and family-size groups will bond and heal best through low-latency, high-resolution multisensory interaction such as shared meals and reciprocated touch; and
Toktarbay, S.; Quevedo, H.
2014-10-01
We present a stationary generalization of the static $q-$metric, the simplest generalization of the Schwarzschild solution that contains a quadrupole parameter. It possesses three independent parameters that are related to the mass, quadrupole moment and angular momentum. We investigate the geometric and physical properties of this exact solution of Einstein's vacuum equations, and show that it can be used to describe the exterior gravitational field of rotating, axially symmetric, compact objects.
GENERAL RELATIVITY AND METRIC OF LOCAL SUPERCLUSTER
Directory of Open Access Journals (Sweden)
Trunev A. P.
2013-12-01
Full Text Available It is shown that the metric of clusters of galaxies should be universal, depending only on the fundamental constants and compatible with the metric of the universe. There are examples of universal metrics obtained in Einstein's theory of gravitation. On the basis of axisymmetric solutions of Einstein’s equation proposed universal metric describing the properties of galaxies, groups and clusters of galaxies
Metrics for Finite Markov Decision Processes
Ferns, Norman; Panangaden, Prakash; Precup, Doina
2012-01-01
We present metrics for measuring the similarity of states in a finite Markov decision process (MDP). The formulation of our metrics is based on the notion of bisimulation for MDPs, with an aim towards solving discounted infinite horizon reinforcement learning tasks. Such metrics can be used to aggregate states, as well as to better structure other value function approximators (e.g., memory-based or nearest-neighbor approximators). We provide bounds that relate our metric distances to the opti...
Almost contact metric 3-submersions
Directory of Open Access Journals (Sweden)
Bill Watson
1984-01-01
Full Text Available An almost contact metric 3-submersion is a Riemannian submersion, π from an almost contact metric manifold (M4m+3,(φi,ξi,ηii=13,g onto an almost quaternionic manifold (N4n,(Jii=13,h which commutes with the structure tensors of type (1,1;i.e., π*φi=Jiπ*, for i=1,2,3. For various restrictions on ∇φi, (e.g., M is 3-Sasakian, we show corresponding limitations on the second fundamental form of the fibres and on the complete integrability of the horizontal distribution. Concommitantly, relations are derived between the Betti numbers of a compact total space and the base space. For instance, if M is 3-quasi-Saskian (dΦ=0, then b1(N≤b1(M. The respective φi-holomorphic sectional and bisectional curvature tensors are studied and several unexpected results are obtained. As an example, if X and Y are orthogonal horizontal vector fields on the 3-contact (a relatively weak structure total space of such a submersion, then the respective holomorphic bisectional curvatures satisfy: Bφi(X,Y=B′J′i(X*,Y*−2. Applications to the real differential geometry of Yarg-Milis field equations are indicated based on the fact that a principal SU(2-bundle over a compactified realized space-time can be given the structure of an almost contact metric 3-submersion.
Metrics for Event Driven Software
Directory of Open Access Journals (Sweden)
Neha Chaudhary
2016-01-01
Full Text Available The evaluation of Graphical User Interface has significant role to improve its quality. Very few metrics exists for the evaluation of Graphical User Interface. The purpose of metrics is to obtain better measurements in terms of risk management, reliability forecast, project scheduling, and cost repression. In this paper structural complexity metrics is proposed for the evaluation of Graphical User Interface. Structural complexity of Graphical User Interface is considered as an indicator of complexity. The goal of identifying structural complexity is to measure the GUI testability. In this testability evaluation the process of measuring the complexity of the user interface from testing perspective is proposed. For the GUI evaluation and calculating structural complexity an assessment process is designed which is based on types of events. A fuzzy model is developed to evaluate the structural complexity of GUI. This model takes five types of events as input and return structural complexity of GUI as output. Further a relationship is established between structural complexity and testability of event driven software. Proposed model is evaluated with four different applications. It is evident from the results that higher the complexities lower the testability of application.
Game Refinement Relations and Metrics
de Alfaro, Luca; Raman, Vishwanath; Stoelinga, Mariëlle
2008-01-01
We consider two-player games played over finite state spaces for an infinite number of rounds. At each state, the players simultaneously choose moves; the moves determine a successor state. It is often advantageous for players to choose probability distributions over moves, rather than single moves. Given a goal, for example, reach a target state, the question of winning is thus a probabilistic one: what is the maximal probability of winning from a given state? On these game structures, two fundamental notions are those of equivalences and metrics. Given a set of winning conditions, two states are equivalent if the players can win the same games with the same probability from both states. Metrics provide a bound on the difference in the probabilities of winning across states, capturing a quantitative notion of state similarity. We introduce equivalences and metrics for two-player game structures, and we show that they characterize the difference in probability of winning games whose goals are expressed in the...
Metric Education. Interpretive Report No. 1.
George Washington Univ., Washington, DC. Inst. for Educational Leadership.
This report reviews the findings of two projects funded by the National Institute of Education (NIE) ano conducted by the American Institutes for Research (AIR). The project reports, "Going Metric" and "Metric Inservice Teacher Training," document the impact of metric conversion on the educational systems of Great Britain, New Zeland, Australia,…
Metrics for Evaluation of Student Models
Pelanek, Radek
2015-01-01
Researchers use many different metrics for evaluation of performance of student models. The aim of this paper is to provide an overview of commonly used metrics, to discuss properties, advantages, and disadvantages of different metrics, to summarize current practice in educational data mining, and to provide guidance for evaluation of student…
Metrics Made Easy: A Classroom Guide - 1978.
Blau, Sharon; And Others
This classroom guide for metric education included a brief rationale and history of metrics, a preliminary metric quiz, a symbol summary, and a list of recommended instructional materials. The guide is comprised primarily of four sections covering the topics of: weight, length, volume, and temperature. Each of these sections contains goals and…
Danilǎ, Bogdan; Harko, Tiberiu; Lobo, Francisco S. N.; Mak, M. K.
2017-02-01
We consider the internal structure and the physical properties of specific classes of neutron, quark and Bose-Einstein condensate stars in the recently proposed hybrid metric-Palatini gravity theory, which is a combination of the metric and Palatini f (R ) formalisms. It turns out that the theory is very successful in accounting for the observed phenomenology, since it unifies local constraints at the Solar System level and the late-time cosmic acceleration, even if the scalar field is very light. In this paper, we derive the equilibrium equations for a spherically symmetric configuration (mass continuity and Tolman-Oppenheimer-Volkoff) in the framework of the scalar-tensor representation of the hybrid metric-Palatini theory, and we investigate their solutions numerically for different equations of state of neutron and quark matter, by adopting for the scalar field potential a Higgs-type form. It turns out that the scalar-tensor definition of the potential can be represented as an Clairaut differential equation, and provides an explicit form for f (R ) given by f (R )˜R +Λeff, where Λeff is an effective cosmological constant. Furthermore, stellar models, described by the stiff fluid, radiation-like, bag model and the Bose-Einstein condensate equations of state are explicitly constructed in both general relativity and hybrid metric-Palatini gravity, thus allowing an in-depth comparison between the predictions of these two gravitational theories. As a general result it turns out that for all the considered equations of state, hybrid gravity stars are more massive than their general relativistic counterparts. Furthermore, two classes of stellar models corresponding to two particular choices of the functional form of the scalar field (constant value, and logarithmic form, respectively) are also investigated. Interestingly enough, in the case of a constant scalar field the equation of state of the matter takes the form of the bag model equation of state describing
Crowdsourcing metrics of digital collections
Directory of Open Access Journals (Sweden)
Tuula Pääkkönen
2015-12-01
Full Text Available In the National Library of Finland (NLF there are millions of digitized newspaper and journal pages, which are openly available via the public website http://digi.kansalliskirjasto.fi. To serve users better, last year the front end was completely overhauled with its main aim in crowdsourcing features, e.g., by giving end-users the opportunity to create digital clippings and a personal scrapbook from the digital collections. But how can you know whether crowdsourcing has had an impact? How much crowdsourcing functionalities have been used so far? Did crowdsourcing work? In this paper the statistics and metrics of a recent crowdsourcing effort are analysed across the different digitized material types (newspapers, journals, ephemera. The subjects, categories and keywords given by the users are analysed to see which topics are the most appealing. Some notable public uses of the crowdsourced article clippings are highlighted. These metrics give us indications on how the end-users, based on their own interests, are investigating and using the digital collections. Therefore, the suggested metrics illustrate the versatility of the information needs of the users, varying from citizen science to research purposes. By analysing the user patterns, we can respond to the new needs of the users by making minor changes to accommodate the most active participants, while still making the service more approachable for those who are trying out the functionalities for the first time. Participation in the clippings and annotations can enrich the materials in unexpected ways and can possibly pave the way for opportunities of using crowdsourcing more also in research contexts. This creates more opportunities for the goals of open science since source data becomes available, making it possible for researchers to reach out to the general public for help. In the long term, utilizing, for example, text mining methods can allow these different end-user segments to
A nonextension result on the spectral metric
Han, Zhigang
2008-01-01
The spectral metric, defined by Schwarz and Oh using Floer-theoretical method, is a bi-invariant metric on the Hamiltonian diffeomorphism group. We show in this note that for certain symplectic manifolds, this metric can not be extended to a bi-invariant metric on the full group of symplectomorphisms. We also study the bounded isometry conjecture of Lalonde and Polterovich in the context of the spectral metric. In particular, we show that the conjecture holds for the torus with all linear symplectic forms.
Angles between Curves in Metric Measure Spaces
Directory of Open Access Journals (Sweden)
Han Bang-Xian
2017-08-01
Full Text Available The goal of the paper is to study the angle between two curves in the framework of metric (and metric measure spaces. More precisely, we give a new notion of angle between two curves in a metric space. Such a notion has a natural interplay with optimal transportation and is particularly well suited for metric measure spaces satisfying the curvature-dimension condition. Indeed one of the main results is the validity of the cosine formula on RCD*(K, N metric measure spaces. As a consequence, the new introduced notions are compatible with the corresponding classical ones for Riemannian manifolds, Ricci limit spaces and Alexandrov spaces.
Statistical Structures on Metric Path Spaces
Institute of Scientific and Technical Information of China (English)
Mircea CRASMAREANU; Cristina-Elena HRETCANU
2012-01-01
The authors extend the notion of statistical structure from Riemannian geometry to the general framework of path spaces endowed with a nonlinear connection and a generalized metric.Two particular cases of statistical data are defined.The existence and uniqueness of a nonlinear connection corresponding to these classes is proved.Two Koszul tensors are introduced in accordance with the Riemannian approach.As applications,the authors treat the Finslerian (α,β)-metrics and the Beil metrics used in relativity and field theories while the support Riemannian metric is the Fisher-Rao metric of a statistical model.
Web metrics for library and information professionals
Stuart, David
2014-01-01
This is a practical guide to using web metrics to measure impact and demonstrate value. The web provides an opportunity to collect a host of different metrics, from those associated with social media accounts and websites to more traditional research outputs. This book is a clear guide for library and information professionals as to what web metrics are available and how to assess and use them to make informed decisions and demonstrate value. As individuals and organizations increasingly use the web in addition to traditional publishing avenues and formats, this book provides the tools to unlock web metrics and evaluate the impact of this content. The key topics covered include: bibliometrics, webometrics and web metrics; data collection tools; evaluating impact on the web; evaluating social media impact; investigating relationships between actors; exploring traditional publications in a new environment; web metrics and the web of data; the future of web metrics and the library and information professional.Th...
Osterhoff, G; Hepp, P; Engel, T; Josten, C
2009-03-01
The case of a 51-year-old patient is presented, with a humeral shaft fracture in combination with an ipsilateral reverse Hill-Sachs lesion, presumably after posterior shoulder dislocation as a result of an electrical accident followed by a fall from a ladder. After corresponding diagnostics, osteosynthesis of the shaft fracture was performed with a locked antegrade intramedullary nail. Simultaneously the reverse Hill-Sachs lesion was elevated und supplemented with the bone core that accrues during drilling of the nail entrance. In the follow-up period good fragment alignment, persistent joint stability and freedom of pain could be observed. On the basis of this case and the current literature the injury mechanism and potential therapy alternatives are discussed.
Comparing Resource Adequacy Metrics: Preprint
Energy Technology Data Exchange (ETDEWEB)
Ibanez, E.; Milligan, M.
2014-09-01
As the penetration of variable generation (wind and solar) increases around the world, there is an accompanying growing interest and importance in accurately assessing the contribution that these resources can make toward planning reserve. This contribution, also known as the capacity credit or capacity value of the resource, is best quantified by using a probabilistic measure of overall resource adequacy. In recognizing the variable nature of these renewable resources, there has been interest in exploring the use of reliability metrics other than loss of load expectation. In this paper, we undertake some comparisons using data from the Western Electricity Coordinating Council in the western United States.
Prince, F; Winter, D A; Sjonnensen, G; Powell, C; Wheeldon, R K
1998-06-01
As more and more prosthetic feet become commercially available, the selection of the appropriate device is a more difficult task for clinical team members. To date, ranking prosthetic feet based on biomechanical parameters has been done using the spring efficiency. The current analytical technique for calculating spring efficiency has two flaws: first, prosthetic feet with a bendable flexible keel are analyzed the same way as those with an articulated ankle and a rigid foot, and second, there is no accounting for the energy losses in the viscoelastic cosmetic material surrounding the keel. This paper develops a rigorous technique to calculate the net energy stored or dissipated and then recovered during the stance phase of gait. Five adults with transtibial amputation were tested with three different prosthetic feet: SACH, Seattle, and Golden-Ankle. The subjects walked at self-selected cadence and stepped on a force plate while two-dimensional segmental kinematic and kinetic data were collected. The results showed that the Golden-Ankle stored or dissipated and then recovered significantly more energy than either the SACH or Seattle. The time to reach foot flat was also significantly reduced for the Golden-Ankle in comparison to both the others. Because the cosmetic material of the SACH foot can store or dissipate and then recover as much energy as the Seattle foot, the SACH foot should be considered an energy-storing foot. Finally, the net efficiency alone can not discriminate adequately among different types of prosthetic feet; therefore, one should consider the time to reach foot flat and the amount of energy recovered as additional objective criteria (weight, maintenance, and cosmesis) for selection of a prosthetic foot device.
Energy Technology Data Exchange (ETDEWEB)
Schroer, Bert
2006-04-15
The holographic encoding is generalized to subalgebras of QFT localized in double cones. It is shown that as a result of this radically different spacetime encoding the modular group acts geometrically on the holographic image. As a result we obtain a formula for localization entropy which is identical to the previously derived formula for the wedge-localized subalgebra. The symmetry group in the holographic encoding turns out to be the Bondi-Metzner-Sachs group. (author)
Directory of Open Access Journals (Sweden)
Francesco Paradisi
2015-01-01
Full Text Available The effects of a non-articulated SACH and a multiaxial foot-ankle mechanism on the performance of low-activity users are of great interest for practitioners in amputee rehabilitation. The aim of this study is to compare these two prosthetic feet and assess possible improvements introduced by the increased degrees of freedom provided by the multiaxial foot. For this purpose, a group of 20 hypomobile transtibial amputees (TTAs had their usual SACH replaced with a multiaxial foot. Participants’ functional mobility, involving ambulatory skills in overground level walking, ramps, and stairs, was evaluated by performing Six-Minute Walking Test (6MWT, Locomotor Capability Index-5 (LCI-5, Hill Assessment Index (HAI, and Stair Assessment Index (SAI. Balance performances were assessed using Berg Balance Scale (BBS and analysing upper body accelerations during gait. Moreover, the Prosthesis Evaluation Questionnaire (PEQ was performed to indicate the prosthesis-related quality of life. Results showed that participants walked faster using the multiaxial foot (p<0.05 maintaining the same upright gait stability. Significant improvements with the multiaxial foot were also observed in BBS, LCI-5, and SAI times and 4 of 9 subscales of the PEQ. Our findings demonstrate that a multiaxial foot represents a considerable alternative solution with respect to the conventional SACH in the prosthetic prescription for hypomobile TTAs.
Paradisi, Francesco; Delussu, Anna Sofia; Brunelli, Stefano; Iosa, Marco; Pellegrini, Roberto; Zenardi, Daniele; Traballesi, Marco
2015-01-01
The effects of a non-articulated SACH and a multiaxial foot-ankle mechanism on the performance of low-activity users are of great interest for practitioners in amputee rehabilitation. The aim of this study is to compare these two prosthetic feet and assess possible improvements introduced by the increased degrees of freedom provided by the multiaxial foot. For this purpose, a group of 20 hypomobile transtibial amputees (TTAs) had their usual SACH replaced with a multiaxial foot. Participants' functional mobility, involving ambulatory skills in overground level walking, ramps, and stairs, was evaluated by performing Six-Minute Walking Test (6 MWT), Locomotor Capability Index-5 (LCI-5), Hill Assessment Index (HAI), and Stair Assessment Index (SAI). Balance performances were assessed using Berg Balance Scale (BBS) and analysing upper body accelerations during gait. Moreover, the Prosthesis Evaluation Questionnaire (PEQ) was performed to indicate the prosthesis-related quality of life. Results showed that participants walked faster using the multiaxial foot (p foot were also observed in BBS, LCI-5, and SAI times and 4 of 9 subscales of the PEQ. Our findings demonstrate that a multiaxial foot represents a considerable alternative solution with respect to the conventional SACH in the prosthetic prescription for hypomobile TTAs.
Metric scales for emotion measurement
Directory of Open Access Journals (Sweden)
Martin Junge
2016-09-01
Full Text Available The scale quality of indirect and direct scalings of the intensity of emotional experiences was investigated from the perspective of representational measurement theory. Study 1 focused on sensory pleasantness and disgust, Study 2 on surprise and amusement, and Study 3 on relief and disappointment. In each study, the emotion intensities elicited by a set of stimuli were estimated using Ordinal Difference Scaling, an indirect probabilistic scaling method based on graded pair comparisons. The obtained scale values were used to select test cases for the quadruple axiom, a central axiom of difference measurement. A parametric bootstrap test was used to decide whether the participants’ difference judgments systematically violated the axiom. Most participants passed this test. The indirect scalings of these participants were then linearly correlated with their direct emotion intensity ratings to determine whether they agreed with them up to measurement error, and hence might be metric as well. The majority of the participants did not pass this test. The findings suggest that Ordinal Difference Scaling allows to measure emotion intensity on a metric scale level for most participants. As a consequence, quantitative emotion theories become amenable to empirical test on the individual level using indirect measurements of emotional experience.
Nutku, Y.; Sheftel, M. B.
2014-02-01
This is a corrected and essentially extended version of the unpublished manuscript by Y Nutku and M Sheftel which contains new results. It is proposed to be published in honour of Y Nutku’s memory. All corrections and new results in sections 1, 2 and 4 are due to M Sheftel. We present new anti-self-dual exact solutions of the Einstein field equations with Euclidean and neutral (ultra-hyperbolic) signatures that admit only one rotational Killing vector. Such solutions of the Einstein field equations are determined by non-invariant solutions of Boyer-Finley (BF) equation. For the case of Euclidean signature such a solution of the BF equation was first constructed by Calderbank and Tod. Two years later, Martina, Sheftel and Winternitz applied the method of group foliation to the BF equation and reproduced the Calderbank-Tod solution together with new solutions for the neutral signature. In the case of Euclidean signature we obtain new metrics which asymptotically locally look like a flat space and have a non-removable singular point at the origin. In the case of ultra-hyperbolic signature there exist three inequivalent forms of metric. Only one of these can be obtained by analytic continuation from the Calderbank-Tod solution whereas the other two are new.
Metrics for building performance assurance
Energy Technology Data Exchange (ETDEWEB)
Koles, G.; Hitchcock, R.; Sherman, M.
1996-07-01
This report documents part of the work performed in phase I of a Laboratory Directors Research and Development (LDRD) funded project entitled Building Performance Assurances (BPA). The focus of the BPA effort is to transform the way buildings are built and operated in order to improve building performance by facilitating or providing tools, infrastructure, and information. The efforts described herein focus on the development of metrics with which to evaluate building performance and for which information and optimization tools need to be developed. The classes of building performance metrics reviewed are (1) Building Services (2) First Costs, (3) Operating Costs, (4) Maintenance Costs, and (5) Energy and Environmental Factors. The first category defines the direct benefits associated with buildings; the next three are different kinds of costs associated with providing those benefits; the last category includes concerns that are broader than direct costs and benefits to the building owner and building occupants. The level of detail of the various issues reflect the current state of knowledge in those scientific areas and the ability of the to determine that state of knowledge, rather than directly reflecting the importance of these issues; it intentionally does not specifically focus on energy issues. The report describes work in progress and is intended as a resource and can be used to indicate the areas needing more investigation. Other reports on BPA activities are also available.
Learning adaptive metric for robust visual tracking.
Jiang, Nan; Liu, Wenyu; Wu, Ying
2011-08-01
Matching the visual appearances of the target over consecutive image frames is the most critical issue in video-based object tracking. Choosing an appropriate distance metric for matching determines its accuracy and robustness, and thus significantly influences the tracking performance. Most existing tracking methods employ fixed pre-specified distance metrics. However, this simple treatment is problematic and limited in practice, because a pre-specified metric does not likely to guarantee the closest match to be the true target of interest. This paper presents a new tracking approach that incorporates adaptive metric learning into the framework of visual object tracking. Collecting a set of supervised training samples on-the-fly in the observed video, this new approach automatically learns the optimal distance metric for more accurate matching. The design of the learned metric ensures that the closest match is very likely to be the true target of interest based on the supervised training. Such a learned metric is discriminative and adaptive. This paper substantializes this new approach in a solid case study of adaptive-metric differential tracking, and obtains a closed-form analytical solution to motion estimation and visual tracking. Moreover, this paper extends the basic linear distance metric learning method to a more powerful nonlinear kernel metric learning method. Extensive experiments validate the effectiveness of the proposed approach, and demonstrate the improved performance of the proposed new tracking method.
Quality Metric Development Framework (qMDF
Directory of Open Access Journals (Sweden)
K. Mustafa
2005-01-01
Full Text Available Several object-oriented metrics have been developed and used in conjunction with the quality models to predict the overall quality of software. However, it may not be enough to propose metrics. The fundamental question may be of their validity, utility and reliability. It may be much significant to be sure that these metrics are really useful and for that their construct validity must be assured. Thereby, good quality metrics must be developed using a foolproof and sound framework / model. A critical review of literature on the attempts in this regard reveals that there is no standard framework or model available for such an important activity. This study presents a framework for the quality metric development called Metric Development Framework (qMDF, which is prescriptive in nature. qMDF is a general framework but it has been established specially with ideas of object-oriented metrics. qMDF has been implemented to develop a good quality design metric, as a validation of proposed framework. Finally, it is defended that adaptation of qMDF by metric developers would yield good quality metrics, while ensuring their construct validity, utility, reliability and reduced developmental effort.
Zhu, Yi-Ming; Lu, Yi; Zhang, Jin; Shen, Jie-Wei; Jiang, Chun-Yan
2011-08-01
Engaging Hill-Sachs lesions are known to be a risk factor for recurrence dislocation after arthroscopic repair in patients with anterior shoulder instability. For a large engaging Hill-Sachs lesion, arthroscopic remplissage is a solution. Arthroscopic Bankart repair combined with the Hill-Sachs remplissage technique can achieve good results without significant impairment of shoulder function. Case Series; Level of evidence, 4. Forty-nine consecutive patients who underwent arthroscopic Bankart repair and Hill-Sachs remplissage for anterior shoulder instability were followed up for a mean duration of 29.0 months (range, 24-35 months). There were 42 males and 7 females with a mean age of 28.4 years (range, 16.7-54.7 years). All patients had diagnosed traumatic unidirectional anterior shoulder instability with a bony lesion of glenoid and an engaging Hill-Sachs lesion. Physical examination, radiographs, and magnetic resonance imaging were performed during postoperative follow-up. The American Shoulder and Elbow Surgeons (ASES) score, Constant score, and Rowe score were used to evaluate shoulder function. The active forward elevation increased a mean of 8.0° (range, -10° to 80°) postoperatively. However, the patients lost 1.9° (range, -40° to 30°) of external rotation to the side. Significant improvement was detected with regard to the ASES score (84.7 vs 96.0, P lesion was shown by magnetic resonance imaging. Arthroscopic Bankart repair combined with Hill-Sachs remplissage can restore shoulder stability without significant impairment of shoulder function in patients with engaging Hill-Sachs lesions.
From Smooth Curves to Universal Metrics
Gurses, Metin; Tekin, Bayram
2016-01-01
A special class of metrics, called universal metrics, solve all gravity theories defined by covariant field equations purely based on the metric tensor. Since we currently lack the knowledge of what the full of quantum corrected field equations of gravity are at a given microscopic length scale, these metrics are particularly important in understanding quantum fields in curved backgrounds in a consistent way. But, finding explicit universal metrics has been a hard problem as there does not seem to be a procedure for it. In this work, we overcome this difficulty and give a construction of universal metrics of d dimensional spacetime from curves constrained to live in a d-1 dimensional Minkowski spacetime or a Euclidean space.
Affine and Projective Tree Metric Theorems
Harel, Matan; Pachter, Lior
2011-01-01
The tree metric theorem provides a combinatorial four point condition that characterizes dissimilarity maps derived from pairwise compatible split systems. A similar (but weaker) four point condition characterizes dissimilarity maps derived from circular split systems (Kalmanson metrics). The tree metric theorem was first discovered in the context of phylogenetics and forms the basis of many tree reconstruction algorithms, whereas Kalmanson metrics were first considered by computer scientists, and are notable in that they are a non-trivial class of metrics for which the traveling salesman problem is tractable. We present a unifying framework for these theorems based on combinatorial structures that are used for graph planarity testing. These are (projective) PC-trees, and their affine analogs, PQ-trees. In the projective case, we generalize a number of concepts from clustering theory, including hierarchies, pyramids, ultrametrics and Robinsonian matrices, and the theorems that relate them. As with tree metric...
From smooth curves to universal metrics
Gürses, Metin; Şişman, Tahsin ćaǧrı; Tekin, Bayram
2016-08-01
A special class of metrics, called universal metrics, solves all gravity theories defined by covariant field equations purely based on the metric tensor. Since we currently lack the knowledge of what the full quantum-corrected field equations of gravity are at a given microscopic length scale, these metrics are particularly important in understanding quantum fields in curved backgrounds in a consistent way. However, finding explicit universal metrics has been a difficult problem as there does not seem to be a procedure for it. In this work, we overcome this difficulty and give a construction of universal metrics of d -dimensional spacetime from curves constrained to live in a (d -1 )-dimensional Minkowski spacetime or a Euclidean space.
Ramified optimal transportation in geodesic metric spaces
Xia, Qinglan
2009-01-01
An optimal transport path may be viewed as a geodesic in the space of probability measures under a suitable family of metrics. This geodesic may exhibit a tree-shaped branching structure in many applications such as trees, blood vessels, draining and irrigation systems. Here, we extend the study of ramified optimal transportation between probability measures from Euclidean spaces to a geodesic metric space. We investigate the existence as well as the behavior of optimal transport paths under various properties of the metric such as completeness, doubling, or curvature upper boundedness. We also introduce the transport dimension of a probability measure on a complete geodesic metric space, and show that the transport dimension of a probability measure is bounded above by the Minkowski dimension and below by the Hausdorff dimension of the measure. Moreover, we introduce a metric, called "the dimensional distance", on the space of probability measures. This metric gives a geometric meaning to the transport dimen...
The Kerr-Newman metric: A Review
Adamo, Tim
2014-01-01
The Kerr-Newman metric describes a very special rotating, charged mass and is the most general of the asymptotically flat stationary 'black hole' solutions to the Einstein-Maxwell equations of general relativity. We review the derivation of this metric from the Reissner-Nordstrom solution by means of a complex transformation algorithm and provide a brief overview of its basic geometric properties. We also include some discussion of interpretive issues, related metrics, and higher-dimensional analogues.
Common Metrics for Human-Robot Interaction
Steinfeld, Aaron; Lewis, Michael; Fong, Terrence; Scholtz, Jean; Schultz, Alan; Kaber, David; Goodrich, Michael
2006-01-01
This paper describes an effort to identify common metrics for task-oriented human-robot interaction (HRI). We begin by discussing the need for a toolkit of HRI metrics. We then describe the framework of our work and identify important biasing factors that must be taken into consideration. Finally, we present suggested common metrics for standardization and a case study. Preparation of a larger, more detailed toolkit is in progress.
A Note on Discrete Einstein Metric
Ge, Huabin
2015-01-01
In this short note, we prove that the space of all admissible piecewise linear metrics parameterized by length square on a triangulated manifolds is a convex cone. We further study Regge's Einstein-Hilbert action and give a much more reasonable definition of discrete Einstein metric than our former version in \\cite{G}. Finally, we introduce a discrete Ricci flow for three dimensional triangulated manifolds, which is closely related to the existence of discrete Einstein metrics.
The definitive guide to IT service metrics
McWhirter, Kurt
2012-01-01
Used just as they are, the metrics in this book will bring many benefits to both the IT department and the business as a whole. Details of the attributes of each metric are given, enabling you to make the right choices for your business. You may prefer and are encouraged to design and create your own metrics to bring even more value to your business - this book will show you how to do this, too.
A Metric Observer for Induction Motors Control
Directory of Open Access Journals (Sweden)
Mohamed Benbouzid
2016-01-01
Full Text Available This paper deals with metric observer application for induction motors. Firstly, assuming that stator currents and speed are measured, a metric observer is designed to estimate the rotor fluxes. Secondly, assuming that only stator currents are measured, another metric observer is derived to estimate rotor fluxes and speed. The proposed observer validity is checked throughout simulations on a 4 kW induction motor drive.
On Nakhleh's metric for reduced phylogenetic networks.
Cardona, Gabriel; Llabrés, Mercè; Rosselló, Francesc; Valiente, Gabriel
2009-01-01
We prove that Nakhleh's metric for reduced phylogenetic networks is also a metric on the classes of tree-child phylogenetic networks, semibinary tree-sibling time consistent phylogenetic networks, and multilabeled phylogenetic trees. We also prove that it separates distinguishable phylogenetic networks. In this way, it becomes the strongest dissimilarity measure for phylogenetic networks available so far. Furthermore, we propose a generalization of that metric that separates arbitrary phylogenetic networks.
Metrics for antibody therapeutics development.
Reichert, Janice M
2010-01-01
A wide variety of full-size monoclonal antibodies (mAbs) and therapeutics derived from alternative antibody formats can be produced through genetic and biological engineering techniques. These molecules are now filling the preclinical and clinical pipelines of every major pharmaceutical company and many biotechnology firms. Metrics for the development of antibody therapeutics, including averages for the number of candidates entering clinical study and development phase lengths for mAbs approved in the United States, were derived from analysis of a dataset of over 600 therapeutic mAbs that entered clinical study sponsored, at least in part, by commercial firms. The results presented provide an overview of the field and context for the evaluation of on-going and prospective mAb development programs. The expansion of therapeutic antibody use through supplemental marketing approvals and the increase in the study of therapeutics derived from alternative antibody formats are discussed.
A Metric Conceptual Space Algebra
Adams, Benjamin; Raubal, Martin
The modeling of concepts from a cognitive perspective is important for designing spatial information systems that interoperate with human users. Concept representations that are built using geometric and topological conceptual space structures are well suited for semantic similarity and concept combination operations. In addition, concepts that are more closely grounded in the physical world, such as many spatial concepts, have a natural fit with the geometric structure of conceptual spaces. Despite these apparent advantages, conceptual spaces are underutilized because existing formalizations of conceptual space theory have focused on individual aspects of the theory rather than the creation of a comprehensive algebra. In this paper we present a metric conceptual space algebra that is designed to facilitate the creation of conceptual space knowledge bases and inferencing systems. Conceptual regions are represented as convex polytopes and context is built in as a fundamental element. We demonstrate the applicability of the algebra to spatial information systems with a proof-of-concept application.
THE QUALITY METRICS OF INFORMATION SYSTEMS
Directory of Open Access Journals (Sweden)
Zora Arsovski
2008-06-01
Full Text Available Information system is a special kind of products which is depend upon great number variables related to nature, conditions during implementation and organizational clime and culture. Because that quality metrics of information system (QMIS has to reflect all previous aspects of information systems. In this paper are presented basic elements of QMIS, characteristics of implementation and operation metrics for IS, team - management quality metrics for IS and organizational aspects of quality metrics. In second part of this paper are presented results of study of QMIS in area of MIS (Management IS.
Einstein Manifolds and Extremal Kahler Metrics
LeBrun, Claude
2010-01-01
In joint work with Chen and Weber, the author has elsewhere shown that CP2#2(-CP2) admits an Einstein metric. The present paper presents a new and rather different proof of the existence of such an Einstein metric, using a variational approach which simultaneously casts new light on the related uniqueness problem. Our results include new existence theorems for extremal Kahler metrics, and these allow one to prove the above existence statement by deforming the Kahler-Einstein metric on CP2#3(-CP2) until bubbling-off occurs.
Reconstructing propagation networks with temporal similarity metrics
Liao, Hao
2014-01-01
Node similarity is a significant property driving the growth of real networks. In this paper, based on the observed spreading results we apply the node similarity metrics to reconstruct propagation networks. We find that the reconstruction accuracy of the similarity metrics is strongly influenced by the infection rate of the spreading process. Moreover, there is a range of infection rate in which the reconstruction accuracy of some similarity metrics drops to nearly zero. In order to improve the similarity-based reconstruction method, we finally propose a temporal similarity metric to take into account the time information of the spreading. The reconstruction results are remarkably improved with the new method.
Radiation-dominated area metric cosmology
Schuller, Frederic P
2007-01-01
We provide further crucial support for a refined, area metric structure of spacetime. Based on the solution of conceptual issues, such as the consistent coupling of fermions and the covariant identification of radiation fields on area metric backgrounds, we show that the radiation-dominated epoch of area metric cosmology is equivalent to that epoch in standard Einstein cosmology. This ensures, in particular, successful nucleosynthesis. This surprising result complements the previously derived prediction of a small late-time acceleration of an area metric universe.
Jalal, Kabir; Carter, Randy L
2015-09-01
For confidentiality reasons, US federal death certificate data are incomplete with regards to the dates of birth and death for the decedents, making calculation of total lifetime of a decedent impossible and thus estimation of mortality incidence difficult. This paper proposes the use of natality data and an imputation-based method to estimate age-specific mortality incidence rates in the face of this missing information. By utilizing previously determined probabilities of birth, a birth date and death date are imputed for every decedent in the dataset. Thus, the birth cohort of each individual is imputed, and the total on-study time can be calculated. This idea is implemented in two approaches for estimation of mortality incidence rates. The first is an extension of a person-time approach, while the second is an extension of a life table approach. Monte Carlo simulations showed that both approaches perform well in comparison to the ideal complete data methods, but that the person-time method is preferred. An application to Tay-Sachs disease is demonstrated. It is concluded that the imputation methods proposed provide valid estimates of the incidence of death from death certificate data without the need for additional assumptions under which usual mortality rates provide valid estimates.
Pasquale, E B; Udgaonkar, J B; Hess, G P
1986-01-01
Extensive chemical kinetic measurements of acetylcholine receptor-controlled ion translocation in membrane vesicles isolated from the electroplax of Electrophorus electricus have led to the proposal of a minimum model which accounts for the activation, desensitization, and voltage-dependent inhibition of the receptor by acetylcholine, suberyldicholine, and carbamoylcholine. Comparison of chemical kinetic measurements of the dynamic properties of the acetylcholine receptor in vesicles with the properties of the receptor in cells obtained from the same organ and animal have been hampered by an inability to make the appropriate measurements with Electrophorus electricus electroplax cells. Here we report a method for exposing and cleaning the surface of electroplax cells obtained from both the Main electric organ and the organ of Sachs and the results of single-channel current recordings which have now become possible. The single-channel current recordings were made in the presence of either carbamoylcholine or suberyldicholine, as a function of temperature and transmembrane voltage. Both the channel open times and the single-channel conductance were measured. The data were found to be consistent with the model based on chemical kinetic measurements using receptor-rich membrane vesicles prepared from the Main electric organ of E. electricus.
Dersh, Devin; Iwamoto, Yuichiro; Argon, Yair
2016-12-01
Loss of function of the enzyme β-hexosaminidase A (HexA) causes the lysosomal storage disorder Tay-Sachs disease (TSD). It has been proposed that mutations in the α chain of HexA can impair folding, enzyme assembly, and/or trafficking, yet there is surprisingly little known about the mechanisms of these potential routes of pathogenesis. We therefore investigated the biosynthesis and trafficking of TSD-associated HexA α mutants, seeking to identify relevant cellular quality control mechanisms. The α mutants E482K and G269S are defective in enzymatic activity, unprocessed by lysosomal proteases, and exhibit altered folding pathways compared with wild-type α. E482K is more severely misfolded than G269S, as observed by its aggregation and inability to associate with the HexA β chain. Importantly, both mutants are retrotranslocated from the endoplasmic reticulum (ER) to the cytosol and are degraded by the proteasome, indicating that they are cleared via ER-associated degradation (ERAD). Leveraging these discoveries, we observed that manipulating the cellular folding environment or ERAD pathways can alter the kinetics of mutant α degradation. Additionally, growth of patient fibroblasts at a permissive temperature or with chemical chaperones increases cellular Hex activity by improving mutant α folding. Therefore modulation of the ER quality control systems may be a potential therapeutic route for improving some forms of TSD.
A novel mutation in the HEXA gene specific to Tay-Sachs disease carriers of Jewish Iraqi origin.
Karpati, M; Peleg, L; Gazit, E; Akstein, E; Goldman, B
2000-05-01
An increased frequency of carriers of 1:140, as defined by reduced hexosaminidase A (HexA) activity, was observed among Iraqi Jews participating in the Tay-Sachs disease (TSD) carrier detection program. Prior to this finding, TSD among Jews had been restricted to those of Eastern European (Ashkenazi) and Moroccan descent with carrier frequencies of 1:29 and 1:110 for Jews of Ashkenazi and Moroccan extraction, respectively. A general, pan-ethnic frequency of approximately 1:280 has been observed among other Jewish Israeli populations. Analysis of 48 DNA samples from Iraqi Jews suspected, by enzymatic assay, to be carriers revealed a total of five mutations, one of which was novel. In nine carriers (19%), a known mutation typical to either Ashkenazi or Moroccan Jews was identified. DeltaF304/ 305 was detected in four individuals, and + 1278TATC in three. G269S and R170Q each appeared in a single person. The new mutation, G749T, resulting in a substitution of glycine to valine at position 250 has been found in 19 of the DNA samples (40%). This mutation was not detected among 100 non-carrier, Iraqi Jews and 65 Ashkenazi enzymatically determined carriers. Aside from Ashkenazi and Moroccan Jews, a specific mutation in the HEXA gene has now also been identified in Jews of Iraqi descent.
Schaefer, Bjoern Malte; Heisenberg, Lavinia
2010-01-01
The subject of this paper is an investigation of the nonlinear contributions to the spectrum of the integrated Sachs-Wolfe (iSW) effect. We derive the corrections to the iSW-auto spectrum and the iSW-tracer cross-spectrum consistently to third order in perturbation theory and analyse the cumulative signal-to-noise ratio for a cross-correlation between the PLANCK and EUCLID data sets as a function of multipole order. We quantify the parameter sensitivity and the statistical error bounds on the cosmological parameters Omega_m, sigma_8, h, n_s and w from the linear iSW-effect and the systematical parameter estimation bias due to the nonlinear corrections in a Fisher-formalism, analysing the error budget in its dependence on multipole order. Our results include: (i) the spectrum of the nonlinear iSW-effect can be measured with 0.8\\sigma statistical significance, (ii) nonlinear corrections dominate the spectrum starting from l=100, (iii) an anticorrelation of the CMB temperature with tracer density on high multipo...
Schäfer, Björn Malte; Kalovidouris, Angelos Fotios; Heisenberg, Lavinia
2011-09-01
The subject of this paper is an investigation of the non-linear contributions to the spectrum of the integrated Sachs-Wolfe (iSW) effect. We derive the corrections to the iSW autospectrum and the iSW-tracer cross-spectrum consistently to third order in perturbation theory and analyse the cumulative signal-to-noise ratio for a cross-correlation between the Planck and Euclid data sets as a function of multipole order. We quantify the parameter sensitivity and the statistical error bounds on the cosmological parameters Ωm, σ8, h, ns and w from the linear iSW effect and the systematical parameter estimation bias due to the non-linear corrections in a Fisher formalism, analysing the error budget in its dependence on multipole order. Our results include the following: (i) the spectrum of the non-linear iSW effect can be measured with 0.8σ statistical significance, (ii) non-linear corrections dominate the spectrum starting from ℓ≃ 102, (iii) an anticorrelation of the CMB temperature with tracer density on high multipoles in the non-linear regime, (iv) a much weaker dependence of the non-linear effect on the dark energy model compared to the linear iSW effect and (v) parameter estimation biases amount to less than 0.1σ and weaker than other systematics.
Mehta, Nikita; Lazarin, Gabriel A; Spiegel, Erica; Berentsen, Kathleen; Brennan, Kelly; Giordano, Jessica; Haque, Imran S; Wapner, Ronald
2016-09-01
Carrier screening for Tay-Sachs disease is performed by sequence analysis of the HEXA gene and/or hexosaminidase A enzymatic activity testing. Enzymatic analysis (EA) has been suggested as the optimal carrier screening method, especially in non-Ashkenazi Jewish (non-AJ) individuals, but its utilization and efficacy have not been fully evaluated in the general population. This study assesses the reliability of EA in comparison with HEXA sequence analysis in non-AJ populations. Five hundred eight Hispanic and African American patients (516 samples) had EA of their leukocytes performed and 12 of these patients who tested positive by EA ("carriers") had subsequent HEXA gene sequencing performed. Of the 508 patients, 25 (4.9%) were EA positive and 40 (7.9%) were inconclusive. Of the 12 patients who were sequenced, 11 did not carry a pathogenic variant and one carried a likely deleterious mutation (NM_000520.4(HEXA):c.1510C>T). High inconclusive rates and poor correlation between positive/inconclusive enzyme results and identification of pathogenic mutations suggest that ethnic-specific recalibration of reference ranges for EA may be necessary. Alternatively, HEXA gene sequencing could be performed.
Doença de Tay-Sachs em criança de raça negra
Directory of Open Access Journals (Sweden)
Sérgio Rosemberg
1970-12-01
Full Text Available É relatado um caso de doença de Tay-Sachs em criança da raça negra. O encontro desta entidade em indivíduos não judeus é bastante raro, sendo este o quinto caso descrito em criança negra. Os autores estudam alguns aspectos genéticos, chegando à conclusão de que o cálculo da freqüência do gene mutante é impossível devido ao pequeno número de casos e ao fato de que não há estimativas seguras quanto à taxa de nascimento de indivíduos negros na população, Em que pese o fato de o diagnóstico se assentar em bases puramente clínicas e anatômicas, prescindindo os autores de exames bioquímicos específicos, os dados apresentados são congruentes com os casos clássicos descritos na literatura.
Dersh, Devin; Iwamoto, Yuichiro; Argon, Yair
2016-01-01
Loss of function of the enzyme β-hexosaminidase A (HexA) causes the lysosomal storage disorder Tay–Sachs disease (TSD). It has been proposed that mutations in the α chain of HexA can impair folding, enzyme assembly, and/or trafficking, yet there is surprisingly little known about the mechanisms of these potential routes of pathogenesis. We therefore investigated the biosynthesis and trafficking of TSD-associated HexA α mutants, seeking to identify relevant cellular quality control mechanisms. The α mutants E482K and G269S are defective in enzymatic activity, unprocessed by lysosomal proteases, and exhibit altered folding pathways compared with wild-type α. E482K is more severely misfolded than G269S, as observed by its aggregation and inability to associate with the HexA β chain. Importantly, both mutants are retrotranslocated from the endoplasmic reticulum (ER) to the cytosol and are degraded by the proteasome, indicating that they are cleared via ER-associated degradation (ERAD). Leveraging these discoveries, we observed that manipulating the cellular folding environment or ERAD pathways can alter the kinetics of mutant α degradation. Additionally, growth of patient fibroblasts at a permissive temperature or with chemical chaperones increases cellular Hex activity by improving mutant α folding. Therefore modulation of the ER quality control systems may be a potential therapeutic route for improving some forms of TSD. PMID:27682588
Institute of Scientific and Technical Information of China (English)
Qing-ge XIE; Ping YANG; Li MENG
2008-01-01
During deformation, the orientation of a grain influences not only the deformation mechanisms (slip or twinning) and the specific selection of activated slip or twinning systems for that grain, but also the kinetics of different types of transformation. Schmid factor analysis was applied to determine the orientation dependency of deformation mechanisms in magnesium alloys AZ31 in this work. The orientation changes after the operation of the specific deformation mechanisms were also calcu-lated based on Sachs model. It was found that different deformation mechanisms proceeded differently according to theoretical predictions. Basal slip occurred when basal planes of grains were tilted toward ND around TD. Prismatic slip dominated when basal planes were approxi-mately perpendicular to TD. Calculation results also indi-cated that the operating of pyramidal slip can not be neglected. {10 12} twinning was favorable when basal planes were approximately normal to RD and { 10 11 } twinning was analyzed to be related to the grains with basal orientations. The operating of slip could greatly suppress the activating of twinning by our Schmid factor analysis. Basal orientations with TD and RD scattering can favor basal slip and tension twinning, respectively, after the operation of compression twinning based on the Schmid factor calculations.
Merkel, Philipp
2012-01-01
In this paper, we recompute contributions to the spectrum of the nonlinear integrated Sachs-Wolfe (iSW)/Rees-Sciama effect in a dark energy cosmology. Focusing on the moderate nonlinear regime, all dynamical fields involved are derived from the density contrast in Eulerian perturbation theory. Shape and amplitude of the resulting angular power spectrum are similar to that derived in previous work. With our purely analytical approach we identify two distinct contributions to the signal of the nonlinear iSW-effect: the change of the gravitational self-energy density of the large scale structure with (conformal) time and gravitational lenses moving with the large scale matter stream. In the latter we recover the Birkinshaw-Gull effect. As the nonlinear iSW-effect itself is inherently hard to detect, observational discrimination between its individual contributions is almost excluded. Our analysis, however, yields valuable insights into the theory of the nonlinear iSW-effect as a post-Newtonian relativistic effec...
Clark, H. Clifford; Richmond, Alan
1983-01-01
Sixth-grade students and teachers were tested to determine students' metric achievement and their teachers' attitudes toward metric instruction after seven years of regular classroom instruction. Results were somewhat disappointing. (MNS)
Information metrics (iMetrics): A research specialty with a socio-cognitive identity?
Milojević, S.; Leydesdorff, L.
2013-01-01
"Bibliometrics", "scientometrics", "informetrics", and "webometrics" can all be considered as manifestations of a single research area with similar objectives and methods, which we call "information metrics" or iMetrics. This study explores the cognitive and social distinctness of iMetrics with resp
Metric of a Slow Rotating Body with Quadrupole Moment from the Erez-Rosen Metric
Frutos-Alfaro, Francisco; Cordero-García, Iván; Ulloa-Esquivel, Oscar
2012-01-01
A metric representing a slow rotating object with quadrupole moment is obtained using the Newman-Janis formalism to include rotation into the weak limit of the Erez-Rosen metric. This metric is intended to tackle relativistic astrometry and gravitational lensing problems in which a quadrupole moment has to be taken into account.
Fuzzy Set Field and Fuzzy Metric
Gebru Gebray; B. Krishna Reddy
2014-01-01
The notation of fuzzy set field is introduced. A fuzzy metric is redefined on fuzzy set field and on arbitrary fuzzy set in a field. The metric redefined is between fuzzy points and constitutes both fuzziness and crisp property of vector. In addition, a fuzzy magnitude of a fuzzy point in a field is defined.
Metrics for Automotive Merchandising, Petroleum Marketing.
Cooper, Gloria S., Ed.; Magisos, Joel H., Ed.
Designed to meet the job-related metric measurement needs of students in automotive merchandising and petroleum marketing classes, this instructional package is one of five for the marketing and distribution cluster, part of a set of 55 packages for metric instruction in different occupations. The package is intended for students who already know…
Invariant metric for nonlinear symplectic maps
Indian Academy of Sciences (India)
Govindan Rangarajan; Minita Sachidanand
2002-03-01
In this paper, we construct an invariant metric in the space of homogeneous polynomials of a given degree (≥ 3). The homogeneous polynomials specify a nonlinear symplectic map which in turn represents a Hamiltonian system. By minimizing the norm constructed out of this metric as a function of system parameters, we demonstrate that the performance of a nonlinear Hamiltonian system is enhanced.
Einstein Hermitian Metrics of Positive Sectional Curvature
Koca, Caner
2011-01-01
In this paper we will prove that the only compact 4-manifold M with an Einstein metric of positive sectional curvature which is also hermitian with respect to some complex structure on M, is the complex projective plane CP^2, with its Fubini-Study metric.
Cluster-based adaptive metric classification
Giotis, Ioannis; Petkov, Nicolai
2012-01-01
Introducing adaptive metric has been shown to improve the results of distance-based classification algorithms. Existing methods are often computationally intensive, either in the training or in the classification phase. We present a novel algorithm that we call Cluster-Based Adaptive Metric (CLAM) c
Finite Metric Spaces of Strictly Negative Type
DEFF Research Database (Denmark)
Hjorth, Poul; Lisonek, P.; Markvorsen, Steen
1998-01-01
We prove that, if a finite metric space is of strictly negative type, then its transfinite diameter is uniquely realized by the infinite extender (load vector). Finite metric spaces that have this property include all spaces on two, three, or four points, all trees, and all finite subspaces of Eu...
Slowly rotating Curzon-Chazy Metric
Montero-Camacho, Paulo; Gutierrez-Chaves, Carlos
2014-01-01
A new rotation version of the Curzon-Chazy metric is found. This new metric was obtained by means of a perturbation method, in order to include slow rotation. The solution is then proved to fulfill the Einstein field equations using a REDUCE program. Furthermore, the applications of this new solution are discussed.
Metrics for Offset Printing Press Operation.
Cooper, Gloria S., Ed.; Magisos, Joel H., Ed.
Designed to meet the job-related metric measurement needs of offset printing press operation students, this instructional package is one of six for the communication media occupations cluster, part of a set of 55 packages for metric instruction in different occupations. The package is intended for students who already know the occupational…
Fixed point theory in metric type spaces
Agarwal, Ravi P; O’Regan, Donal; Roldán-López-de-Hierro, Antonio Francisco
2015-01-01
Written by a team of leading experts in the field, this volume presents a self-contained account of the theory, techniques and results in metric type spaces (in particular in G-metric spaces); that is, the text approaches this important area of fixed point analysis beginning from the basic ideas of metric space topology. The text is structured so that it leads the reader from preliminaries and historical notes on metric spaces (in particular G-metric spaces) and on mappings, to Banach type contraction theorems in metric type spaces, fixed point theory in partially ordered G-metric spaces, fixed point theory for expansive mappings in metric type spaces, generalizations, present results and techniques in a very general abstract setting and framework. Fixed point theory is one of the major research areas in nonlinear analysis. This is partly due to the fact that in many real world problems fixed point theory is the basic mathematical tool used to establish the existence of solutions to problems which arise natur...
Cluster-based adaptive metric classification
Giotis, Ioannis; Petkov, Nicolai
2012-01-01
Introducing adaptive metric has been shown to improve the results of distance-based classification algorithms. Existing methods are often computationally intensive, either in the training or in the classification phase. We present a novel algorithm that we call Cluster-Based Adaptive Metric (CLAM)
Discrete homology theory for metric spaces
H. Barcelo (Hélène); V. Capraro (Valerio); J. A. White; H. Barcelo (Hélène)
2014-01-01
htmlabstractWe define and study a notion of discrete homology theory for metric spaces. Instead of working with simplicial homology, our chain complexes are given by Lipschitz maps from an n n -dimensional cube to a fixed metric space. We prove that the resulting homology theory satisfies a
Program for implementing software quality metrics
Energy Technology Data Exchange (ETDEWEB)
Yule, H.P.; Riemer, C.A.
1992-04-01
This report describes a program by which the Veterans Benefit Administration (VBA) can implement metrics to measure the performance of automated data systems and demonstrate that they are improving over time. It provides a definition of quality, particularly with regard to software. Requirements for management and staff to achieve a successful metrics program are discussed. It lists the attributes of high-quality software, then describes the metrics or calculations that can be used to measure these attributes in a particular system. Case studies of some successful metrics programs used by business are presented. The report ends with suggestions on which metrics the VBA should use and the order in which they should be implemented.
Deformations of three-dimensional metrics
Pugliese, Daniela; Stornaiolo, Cosimo
2015-03-01
We examine three-dimensional metric deformations based on a tetrad transformation through the action the matrices of scalar field. We describe by this approach to deformation the results obtained by Coll et al. (Gen. Relativ. Gravit. 34:269, 2002), where it is stated that any three-dimensional metric was locally obtained as a deformation of a constant curvature metric parameterized by a 2-form. To this aim, we construct the corresponding deforming matrices and provide their classification according to the properties of the scalar and of the vector used in Coll et al. (Gen Relativ Gravit 34:269, 2002) to deform the initial metric. The resulting causal structure of the deformed geometries is examined, too. Finally we apply our results to a spherically symmetric three geometry and to a space sector of Kerr metric.
FABASOFT BEST PRACTICES AND TEST METRICS MODEL
Directory of Open Access Journals (Sweden)
Nadica Hrgarek
2007-06-01
Full Text Available Software companies have to face serious problems about how to measure the progress of test activities and quality of software products in order to estimate test completion criteria, and if the shipment milestone will be reached on time. Measurement is a key activity in testing life cycle and requires established, managed and well documented test process, defined software quality attributes, quantitative measures, and using of test management and bug tracking tools. Test metrics are a subset of software metrics (product metrics, process metrics and enable the measurement and quality improvement of test process and/or software product. The goal of this paper is to briefly present Fabasoft best practices and lessons learned during functional and system testing of big complex software products, and to describe a simple test metrics model applied to the software test process with the purpose to better control software projects, measure and increase software quality.
Smart Grid Status and Metrics Report Appendices
Energy Technology Data Exchange (ETDEWEB)
Balducci, Patrick J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Antonopoulos, Chrissi A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Clements, Samuel L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Gorrissen, Willy J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kirkham, Harold [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Ruiz, Kathleen A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Smith, David L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Weimar, Mark R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Gardner, Chris [APQC, Houston, TX (United States); Varney, Jeff [APQC, Houston, TX (United States)
2014-07-01
A smart grid uses digital power control and communication technology to improve the reliability, security, flexibility, and efficiency of the electric system, from large generation through the delivery systems to electricity consumers and a growing number of distributed generation and storage resources. To convey progress made in achieving the vision of a smart grid, this report uses a set of six characteristics derived from the National Energy Technology Laboratory Modern Grid Strategy. The Smart Grid Status and Metrics Report defines and examines 21 metrics that collectively provide insight into the grid’s capacity to embody these characteristics. This appendix presents papers covering each of the 21 metrics identified in Section 2.1 of the Smart Grid Status and Metrics Report. These metric papers were prepared in advance of the main body of the report and collectively form its informational backbone.
Topology on locally finite metric spaces
Capraro, Valerio
2011-01-01
The necessity of a theory of General Topology and, most of all, of Algebraic Topology on locally finite metric spaces comes from many areas of research in both Applied and Pure Mathematics: Molecular Biology, Mathematical Chemistry, Computer Science, Topological Graph Theory and Metric Geometry. In this paper we propose the basic notions of such a theory and some applications: we replace the classical notions of continuous function, homeomorphism and homotopic equivalence with the notions of NPP-function, NPP-local-isomorphism and NPP-homotopy (NPP stands for Nearest Point Preserving); we also introduce the notion of NPP-isomorphism. We construct three invariants under NPP-isomorphisms and, in particular, we define the fundamental group of a locally finite metric space. As first applications, we propose the following: motivated by the longstanding question whether there is a purely metric condition which extends the notion of amenability of a group to any metric space, we propose the property SN (Small Neighb...
Metrics for Polyphonic Sound Event Detection
Directory of Open Access Journals (Sweden)
Annamaria Mesaros
2016-05-01
Full Text Available This paper presents and discusses various metrics proposed for evaluation of polyphonic sound event detection systems used in realistic situations where there are typically multiple sound sources active simultaneously. The system output in this case contains overlapping events, marked as multiple sounds detected as being active at the same time. The polyphonic system output requires a suitable procedure for evaluation against a reference. Metrics from neighboring fields such as speech recognition and speaker diarization can be used, but they need to be partially redefined to deal with the overlapping events. We present a review of the most common metrics in the field and the way they are adapted and interpreted in the polyphonic case. We discuss segment-based and event-based definitions of each metric and explain the consequences of instance-based and class-based averaging using a case study. In parallel, we provide a toolbox containing implementations of presented metrics.
The metrics of science and technology
Geisler, Eliezer
2000-01-01
Dr. Geisler's far-reaching, unique book provides an encyclopedic compilation of the key metrics to measure and evaluate the impact of science and technology on academia, industry, and government. Focusing on such items as economic measures, patents, peer review, and other criteria, and supported by an extensive review of the literature, Dr. Geisler gives a thorough analysis of the strengths and weaknesses inherent in metric design, and in the use of the specific metrics he cites. His book has already received prepublication attention, and will prove especially valuable for academics in technology management, engineering, and science policy; industrial R&D executives and policymakers; government science and technology policymakers; and scientists and managers in government research and technology institutions. Geisler maintains that the application of metrics to evaluate science and technology at all levels illustrates the variety of tools we currently possess. Each metric has its own unique strengths and...
Algorithms for Game Metrics (Full Version)
Chatterjee, Krishnendu; Majumdar, Rupak; Raman, Vishwanath
2008-01-01
Simulation and bisimulation metrics for stochastic systems provide a quantitative generalization of the classical simulation and bisimulation relations. These metrics capture the similarity of states with respect to quantitative specifications written in the quantitative mu-calculus and related probabilistic logics. We show that game metrics, besides being logically characterized by the quantitative mu-calculus, also provide a bound for discounted and long-run average values of games. We then present algorithms for computing the metrics on Markov decision processes (MDPs), turn-based stochastic games, and concurrent games. For turn-based games and MDPs, we provide a polynomial-time algorithm for the computation of the one-step metric distance between states. The algorithm is based on linear programming. For concurrent games, we show that computing the exact distance between states is at least as hard as computing the value of concurrent reachability games and the square-root-sum problem in computational geome...
Geometry of manifolds with area metric
Schuller, F P
2005-01-01
We construct the differential geometry of smooth manifolds equipped with an algebraic curvature map acting as an area measure. Area metric geometry provides a spacetime structure suitable for the discussion of gauge theories and strings, and is considerably more general than Lorentzian geometry. Our construction of geometrically relevant objects, such as an area metric compatible connection and derived tensors, makes essential use of a decomposition theorem due to Gilkey, showing that a general area metric is generated by a finite collection of metrics rather than by a single one. Employing curvature invariants for area metric manifolds we devise an entirely new class of gravity theories with inherently stringy character, and discuss gauge matter actions.
String Rearrangement Metrics: A Survey
Amir, Amihood; Levy, Avivit
A basic assumption in traditional pattern matching is that the order of the elements in the given input strings is correct, while the description of the content, i.e. the description of the elements, may be erroneous. Motivated by questions that arise in Text Editing, Computational Biology, Bit Torrent and Video on Demand, and Computer Architecture, a new pattern matching paradigm was recently proposed by [2]. In this model, the pattern content remains intact, but the relative positions may change. Several papers followed the initial definition of the new paradigm. Each paper revealed new aspects in the world of string rearrangement metrics. This new unified view has already proven itself by enabling the solution of an open problem of the mathematician Cayley from 1849. It also gave better insight to problems that were already studied in different and limited situations, such as the behavior of different cost functions, and enabled deriving results for cost functions that were not yet sufficiently analyzed by previous research. At this stage, a general understanding of this new model is beginning to coalesce. The aim of this survey is to present an overview of this recent new direction of research, the problems, the methodologies, and the state-of-the-art.
Metrics for border management systems.
Energy Technology Data Exchange (ETDEWEB)
Duggan, Ruth Ann
2009-07-01
There are as many unique and disparate manifestations of border systems as there are borders to protect. Border Security is a highly complex system analysis problem with global, regional, national, sector, and border element dimensions for land, water, and air domains. The complexity increases with the multiple, and sometimes conflicting, missions for regulating the flow of people and goods across borders, while securing them for national security. These systems include frontier border surveillance, immigration management and customs functions that must operate in a variety of weather, terrain, operational conditions, cultural constraints, and geopolitical contexts. As part of a Laboratory Directed Research and Development Project 08-684 (Year 1), the team developed a reference framework to decompose this complex system into international/regional, national, and border elements levels covering customs, immigration, and border policing functions. This generalized architecture is relevant to both domestic and international borders. As part of year two of this project (09-1204), the team determined relevant relative measures to better understand border management performance. This paper describes those relative metrics and how they can be used to improve border management systems.
Entropy of continuous maps on quasi-metric spaces
Sayyari, Y.; Molaei, M.; Moghayer, S.M.
2015-01-01
The category of metric spaces is a subcategory of quasi-metric spaces. In this paper the notion of entropy for the continuous maps of a quasi-metric space is extended via spanning and separated sets. Moreover, two metric spaces that are associated to a given quasi-metric space are introduced and the
A New Metrics for Hierarchical Clustering
Institute of Scientific and Technical Information of China (English)
YANGGuangwen; SHIShuming; WANGDingxing
2003-01-01
Hierarchical clustering is a popular method of performing unsupervised learning. Some metric must be used to determine the similarity between pairs of clusters in hierarchical clustering. Traditional similarity metrics either can deal with simple shapes (i.e. spherical shapes) only or are very sensitive to outliers (the chaining effect). The main contribution of this paper is to propose some potential-based similarity metrics (APES and AMAPES) between clusters in hierarchical clustering, inspired by the concepts of the electric potential and the gravitational potential in electromagnetics and astronomy. The main features of these metrics are: the first, they have strong antijamming capability; the second, they are capable of finding clusters of different shapes such as spherical, spiral, chain, circle, sigmoid, U shape or other complex irregular shapes; the third, existing algorithms and research fruits for classical metrics can be adopted to deal with these new potential-based metrics with no or little modification. Experiments showed that the new metrics are more superior to traditional ones. Different potential functions are compared, and the sensitivity to parameters is also analyzed in this paper.
Robust Transfer Metric Learning for Image Classification.
Ding, Zhengming; Fu, Yun
2017-02-01
Metric learning has attracted increasing attention due to its critical role in image analysis and classification. Conventional metric learning always assumes that the training and test data are sampled from the same or similar distribution. However, to build an effective distance metric, we need abundant supervised knowledge (i.e., side/label information), which is generally inaccessible in practice, because of the expensive labeling cost. In this paper, we develop a robust transfer metric learning (RTML) framework to effectively assist the unlabeled target learning by transferring the knowledge from the well-labeled source domain. Specifically, RTML exploits knowledge transfer to mitigate the domain shift in two directions, i.e., sample space and feature space. In the sample space, domain-wise and class-wise adaption schemes are adopted to bridge the gap of marginal and conditional distribution disparities across two domains. In the feature space, our metric is built in a marginalized denoising fashion and low-rank constraint, which make it more robust to tackle noisy data in reality. Furthermore, we design an explicit rank constraint regularizer to replace the rank minimization NP-hard problem to guide the low-rank metric learning. Experimental results on several standard benchmarks demonstrate the effectiveness of our proposed RTML by comparing it with the state-of-the-art transfer learning and metric learning algorithms.
Altmetrics - a complement to conventional metrics.
Melero, Remedios
2015-01-01
Emerging metrics based on article-level does not exclude traditional metrics based on citations to the journal, but complements them. Both can be employed in conjunction to offer a richer picture of an article use from immediate to long terms. Article-level metrics (ALM) is the result of the aggregation of different data sources and the collection of content from multiple social network services. Sources used for the aggregation can be broken down into five categories: usage, captures, mentions, social media and citations. Data sources depend on the tool, but they include classic metrics indicators based on citations, academic social networks (Mendeley, CiteULike, Delicious) and social media (Facebook, Twitter, blogs, or Youtube, among others). Altmetrics is not synonymous with alternative metrics. Altmetrics are normally early available and allow to assess the social impact of scholarly outputs, almost at the real time. This paper overviews briefly the meaning of altmetrics and describes some of the existing tools used to apply this new metrics: Public Library of Science--Article-Level Metrics, Altmetric, Impactstory and Plum.
Altmetrics – a complement to conventional metrics
Melero, Remedios
2015-01-01
Emerging metrics based on article-level does not exclude traditional metrics based on citations to the journal, but complements them. Both can be employed in conjunction to offer a richer picture of an article use from immediate to long terms. Article-level metrics (ALM) is the result of the aggregation of different data sources and the collection of content from multiple social network services. Sources used for the aggregation can be broken down into five categories: usage, captures, mentions, social media and citations. Data sources depend on the tool, but they include classic metrics indicators based on citations, academic social networks (Mendeley, CiteULike, Delicious) and social media (Facebook, Twitter, blogs, or Youtube, among others). Altmetrics is not synonymous with alternative metrics. Altmetrics are normally early available and allow to assess the social impact of scholarly outputs, almost at the real time. This paper overviews briefly the meaning of altmetrics and describes some of the existing tools used to apply this new metrics: Public Library of Science - Article-Level Metrics, Altmetric, Impactstory and Plum. PMID:26110028
Starostina, Elena; Xu, Aiguo; Lin, Heping; Pikielny, Claudio W
2009-01-02
Low volatility, lipid-like cuticular hydrocarbon pheromones produced by Drosophila melanogaster females play an essential role in triggering and modulating mating behavior, but the chemosensory mechanisms involved remain poorly understood. Recently, we showed that the CheB42a protein, which is expressed in only 10 pheromone-sensing taste hairs on the front legs of males, modulates progression to late stages of male courtship behavior in response to female-specific cuticular hydrocarbons. Here we report that expression of all 12 genes in the CheB gene family is predominantly or exclusively gustatory-specific, and occurs in many different, often non-overlapping patterns. Only the Gr family of gustatory receptor genes displays a comparable variety of gustatory-specific expression patterns. Unlike Grs, however, expression of all but one CheB gene is sexually dimorphic. Like CheB42a, other CheBs may therefore function specifically in gustatory perception of pheromones. We also show that CheBs belong to the ML superfamily of lipid-binding proteins, and are most similar to human GM2-activator protein (GM2-AP). In particular, GM2-AP residues involved in ligand binding are conserved in CheBs but not in other ML proteins. Finally, CheB42a is specifically secreted into the inner lumen of pheromone-sensing taste hairs, where pheromones interact with membrane-bound receptors. We propose that CheB proteins interact directly with lipid-like Drosophila pheromones and modulate their detection by the gustatory signal transduction machinery. Furthermore, as loss of GM2-AP in Tay-Sachs disease prevents degradation of GM2 gangliosides and results in neurodegeneration, the function of CheBs in pheromone response may involve biochemical mechanisms critical for lipid metabolism in human neurons.
Directory of Open Access Journals (Sweden)
Prasanna K. Lenka
2008-12-01
Full Text Available Objective: to investigate the changes associated with age in gait characteristics and dynamic weight bearing pattern of sound and prosthetic limb of persons with unilateral amputation. Participant: two groups of seven young (24±3.8 years and seven elderly unilateral amputee (71±6 years were selected for this study. Setting: both groups walked at their self selected speed over a 20 second duration plane surface walk way in trans-tibial prosthesis with PTB socket and SACH foot. The raw data of force and EMG sensors of gait analyzer were filtered, processed and analyzed with help of ‘matlab 7.0. A blue tooth enabled heart rate telemetry system was used for calculating gait efficiency in terms of physiological cost index (PCI. Results: significant differences were found in stride duration, (p=0.003, step duration sound limb (p<0.002, stance duration sound limb (p=0.002, stance duration prosthetic limb (p=0.006 and cadence (p=0.001<0.05, however no difference was found in EMG pattern of vastus lateralis between the two groups. The dynamic weight distribution showed more normalized load on anterior parts of heel and minimum load at calcaneal max in elderly group. The results of vertical ground reaction force found the prosthetic side of elderly group takes more weight than young group during loading response. In comparison, PCI was observed to be greater in case of elderly group. Conclusion: most of difference between two groups could be explained by speed variations and biomechanical limitation of ankle joint due to natural aging process.
Melas, Evangelos
2017-07-01
The original Bondi-Metzner-Sachs (BMS) group B is the common asymptotic symmetry group of all asymptotically flat Lorentzian radiating 4-dim space-times. As such, B is the best candidate for the universal symmetry group of General Relativity (G.R.). In 1973, with this motivation, McCarthy classified all relativistic B-invariant systems in terms of strongly continuous irreducible unitary representations (IRS) of B. Here we introduce the analogue B(2, 1) of the BMS group B in 3 space-time dimensions. B(2, 1) itself admits thirty-four analogues both real in all signatures and in complex space-times. In order to find the IRS of both B(2, 1) and its analogues, we need to extend Wigner-Mackey's theory of induced representations. The necessary extension is described and is reduced to the solution of three problems. These problems are solved in the case where B(2, 1) and its analogues are equipped with the Hilbert topology. The extended theory is necessary in order to construct the IRS of both B and its analogues in any number d of space-time dimensions, d ≥3 , and also in order to construct the IRS of their supersymmetric counterparts. We use the extended theory to obtain the necessary data in order to construct the IRS of B(2, 1). The main results of the representation theory are as follows: The IRS are induced from "little groups" which are compact. The finite "little groups" are cyclic groups of even order. The inducing construction is exhaustive notwithstanding the fact that B(2, 1) is not locally compact in the employed Hilbert topology.
Merolla, Giovanni; Porcellini, Giuseppe
2014-04-01
Giovanni Merolla Co-investigator: Giuseppe Porcellini Investigation performed at the Biomechanics Laboratory "Marco Simoncelli", D. Cervesi Hospital, Cattolica - Italy PLAN OF CLINICAL INVESTIGATION (PCI): Version 1.0 of June 12, 2012 Approved by AV/IRST Ethical Committee (Comitato Etico Area Vasta Romagna) and authorized by AUSL RN ("Determina AUSL Rimini numero 326 del 29/03/2013: Remplissage U.O Chirurgia della Spalla - Valutazione clinica ed ultrasonografica dell'infraspinato dopo capsulo-tenodesi artroscopica (remplissage) nell'instabilità anteriore traumatica di spalla con lesione di Bankart e difetto omerale di Hill-Sachs").
Meiser, Jerome; Urbassek, Herbert M.
2016-08-01
Using classical molecular dynamics simulations and the Meyer-Entel interaction potential, we study the martensitic transformation pathway in a pure iron bi-crystal containing a symmetric tilt grain boundary. Upon cooling the system from the austenitic phase, the transformation starts with the nucleation of the martensitic phase near the grain boundary in a plate-like arrangement. The Kurdjumov-Sachs orientation relations are fulfilled at the plates. During further cooling, the plates expand and merge. In contrast to the orientation relation in the plate structure, the complete transformation proceeds via the Pitsch pathway.
Metric Entropy of Nonautonomous Dynamical Systems
Directory of Open Access Journals (Sweden)
Kawan Christoph
2014-01-01
Full Text Available We introduce the notion of metric entropy for a nonautonomous dynamical system given by a sequence (Xn; μn of probability spaces and a sequence of measurable maps fn : Xn → Xn+1 with fnμn = μn+1. This notion generalizes the classical concept of metric entropy established by Kolmogorov and Sinai, and is related via a variational inequality to the topological entropy of nonautonomous systems as defined by Kolyada, Misiurewicz, and Snoha. Moreover, it shares several properties with the classical notion of metric entropy. In particular, invariance with respect to appropriately defined isomorphisms, a power rule, and a Rokhlin-type inequality are proved
Finite Metric Spaces of Strictly negative Type
DEFF Research Database (Denmark)
Hjorth, Poul G.
If a finite metric space is of strictly negative type then its transfinite diameter is uniquely realized by an infinite extent (“load vector''). Finite metric spaces that have this property include all trees, and all finite subspaces of Euclidean and Hyperbolic spaces. We prove that if the distan...... matrix of a finite metric space is both hypermetric and regular, then it is of strictly negative type. We show that the strictly negative type finite subspaces of spheres are precisely those which do not contain two pairs of antipodal points....
Software metrics a rigorous and practical approach
Fenton, Norman
2014-01-01
A Framework for Managing, Measuring, and Predicting Attributes of Software Development Products and ProcessesReflecting the immense progress in the development and use of software metrics in the past decades, Software Metrics: A Rigorous and Practical Approach, Third Edition provides an up-to-date, accessible, and comprehensive introduction to software metrics. Like its popular predecessors, this third edition discusses important issues, explains essential concepts, and offers new approaches for tackling long-standing problems.New to the Third EditionThis edition contains new material relevant
Holographic computations of the Quantum Information Metric
Trivella, Andrea
2016-01-01
In this note we show how the Quantum Information Metric can be computed holographically using a perturbative approach. In particular when the deformation of the conformal field theory state is induced by a scalar operator the corresponding bulk configuration reduces to a scalar field perturbatively probing the unperturbed background. We study two concrete examples: a CFT ground state deformed by a primary operator and thermofield double state in $d=2$ deformed by a marginal operator. Finally, we generalize the bulk construction to the case of a multi dimensional parameter space and show that the Quantum Information Metric coincides with the metric of the non-linear sigma model for the corresponding scalar fields.
Generalized Painlev\\'e-Gullstrand metrics
Lin, Chun-Yu
2008-01-01
An obstruction to the implementation of spatially flat Painleve-Gullstrand(PG) slicings is demonstrated, and explicitly discussed for Reissner-Nordstrom and Schwarzschild-anti-deSitter spacetimes. Generalizations of PG slicings which are not spatially flat but which remain regular at the horizons are introduced. These metrics can be obtained from standard spherically symmetric metrics by physical Lorentz boosts. With these generalized PG metrics, problematic contributions to the imaginary part of the action in the Parikh-Wilczek derivation of Hawking radiation due to the obstruction can be avoided.
Applying Sigma Metrics to Reduce Outliers.
Litten, Joseph
2017-03-01
Sigma metrics can be used to predict assay quality, allowing easy comparison of instrument quality and predicting which tests will require minimal quality control (QC) rules to monitor the performance of the method. A Six Sigma QC program can result in fewer controls and fewer QC failures for methods with a sigma metric of 5 or better. The higher the number of methods with a sigma metric of 5 or better, the lower the costs for reagents, supplies, and control material required to monitor the performance of the methods.
p-Hausdorff度量%p-Hausdorff metric
Institute of Scientific and Technical Information of China (English)
何日高
2011-01-01
According to the properties of Firey combination,we first introduce the p-Hausdorff metric,which coincides with the well-known Hausdorff metric in the case p = 1.Then we give two important results on the p-Hausdorff metric.%根据Firey组合的属性,引入p-Hausdorff度量,特别地,当p=1时,p-Hausdorff度量就是著名的Hausdorff度量.进一步运用凸几何分析理论证明关于p-Hausdorff度量的2个重要结论.
Propagation of light in area metric backgrounds
Energy Technology Data Exchange (ETDEWEB)
Punzi, Raffaele; Wohlfarth, Mattias N R [Zentrum fuer Mathematische Physik und II. Institut fuer Theoretische Physik, Universitaet Hamburg, Luruper Chaussee 149, 22761 Hamburg (Germany); Schuller, Frederic P, E-mail: raffaele.punzi@desy.d, E-mail: fps@aei.mpg.d, E-mail: mattias.wohlfarth@desy.d [Max Planck Institut fuer Gravitationsphysik, Albert Einstein Institut, Am Muehlenberg 1, 14467 Potsdam (Germany)
2009-02-07
The propagation of light in area metric spacetimes, which naturally emerge as refined backgrounds in quantum electrodynamics and quantum gravity, is studied from first principles. In the geometric-optical limit, light rays are found to follow geodesics in a Finslerian geometry, with the Finsler norm being determined by the area metric tensor. Based on this result, and an understanding of the nonlinear relation between ray vectors and wave covectors in such refined backgrounds, we study light deflection in spherically symmetric situations and obtain experimental bounds on the non-metricity of spacetime in the solar system.
Metrics of Risk Associated with Defects Rediscovery
Miranskyy, Andriy V; Reesor, Mark
2011-01-01
Software defects rediscovered by a large number of customers affect various stakeholders and may: 1) hint at gaps in a software manufacturer's Quality Assurance (QA) processes, 2) lead to an over-load of a software manufacturer's support and maintenance teams, and 3) consume customers' resources, leading to a loss of reputation and a decrease in sales. Quantifying risk associated with the rediscovery of defects can help all of these stake-holders. In this chapter we present a set of metrics needed to quantify the risks. The metrics are designed to help: 1) the QA team to assess their processes; 2) the support and maintenance teams to allocate their resources; and 3) the customers to assess the risk associated with using the software product. The paper includes a validation case study which applies the risk metrics to industrial data. To calculate the metrics we use mathematical instruments like the heavy-tailed Kappa distribution and the G/M/k queuing model.
Classroom reconstruction of the Schwarzschild metric
Kassner, Klaus
2015-01-01
A promising way to introduce general relativity in the classroom is to study the physical predictions that follow from certain given metrics, such as the Schwarzschild one. This involves lower mathematical expenditure than an approach focusing on differential geometry in its full glory and permits to emphasize physical aspects before attacking the field equations. Even so, in terms of motivation, lacking justification of the metric employed may pose an obstacle. The paper discusses how to establish the weak-field limit of the Schwarzschild metric with a minimum of relatively simple physical assumptions. Since this does not appear sufficient to arrive at a form of the metric useful for more than the most basic predictions (gravitational redshift), the determination of a single additional parameter from experiment is admitted. An attractive experimental candidate is the measurement of the perihelion precession of Mercury, because the result was already known before the completion of general relativity. It is sh...
Flight Crew State Monitoring Metrics Project
National Aeronautics and Space Administration — eSky will develop specific crew state metrics based on the timeliness, tempo and accuracy of pilot inputs required by the H-mode Flight Control System (HFCS)....
Metrics, Media and Advertisers: Discussing Relationship
Directory of Open Access Journals (Sweden)
Marco Aurelio de Souza Rodrigues
2014-11-01
Full Text Available This study investigates how Brazilian advertisers are adapting to new media and its attention metrics. In-depth interviews were conducted with advertisers in 2009 and 2011. In 2009, new media and its metrics were celebrated as innovations that would increase advertising campaigns overall efficiency. In 2011, this perception has changed: New media’s profusion of metrics, once seen as an advantage, started to compromise its ease of use and adoption. Among its findings, this study argues that there is an opportunity for media groups willing to shift from a product-focused strategy towards a customer-centric one, through the creation of new, simple and integrative metrics.
Software Metrics Evaluation Based on Entropy
Selvarani, R; Ramachandran, Muthu; Prasad, Kamakshi
2010-01-01
Software engineering activities in the Industry has come a long way with various improve- ments brought in various stages of the software development life cycle. The complexity of modern software, the commercial constraints and the expectation for high quality products demand the accurate fault prediction based on OO design metrics in the class level in the early stages of software development. The object oriented class metrics are used as quality predictors in the entire OO software development life cycle even when a highly iterative, incremental model or agile software process is employed. Recent research has shown some of the OO design metrics are useful for predicting fault-proneness of classes. In this paper the empirical validation of a set of metrics proposed by Chidamber and Kemerer is performed to assess their ability in predicting the software quality in terms of fault proneness and degradation. We have also proposed the design complexity of object-oriented software with Weighted Methods per Class m...
Medicare Contracting - Redacted Benchmark Metric Reports
U.S. Department of Health & Human Services — The Centers for Medicare and Medicaid Services has compiled aggregate national benchmark cost and workload metrics using data submitted to CMS by the AB MACs and the...
NPScape Metric GIS Data - Conservation Status
National Park Service, Department of the Interior — NPScape conservation status metrics are calculated using data from the USGS Gap Analysis Program (PAD-US), World Protected Areas Database (WDPA), and National Marine...
MPLS/VPN traffic engineering: SLA metrics
Cherkaoui, Omar; MacGibbon, Brenda; Blais, Michel; Serhrouchni, Ahmed
2001-07-01
Traffic engineering must be concerned with a broad definition of service that includes network availability, reliability and stability, as well as traditional traffic data on loss, throughput, delay and jitter. MPLS and Virtual Private Networks (VPNs) significantly contribute to security and Quality of Service (QoS) within communication networks, but there remains a need for metric measurement and evaluation. The purpose of this paper is to propose a methodology which gives a measure for LSP ( Lfew abel Switching Paths) metrics in VPN MPLS networks. We propose here a statistical method for the evaluation of those metrics. Statistical methodology is very important in this type of study since there is a large amount of data to consider. We use the notions of sample surveys, self-similar processes, linear regression, additive models and bootstrapping. The results obtained allows us to estimate the different metrics for such SLAs.
Metrics and Energy Landscapes in Irreversible Thermodynamics
Directory of Open Access Journals (Sweden)
Bjarne Andresen
2015-09-01
Full Text Available We describe how several metrics are possible in thermodynamic state space but that only one, Weinhold’s, has achieved widespread use. Lengths calculated based on this metric have been used to bound dissipation in finite-time (irreversible processes be they continuous or discrete, and described in the energy picture or the entropy picture. Examples are provided from thermodynamics of heat conversion processes as well as chemical reactions. Even losses in economics can be bounded using a thermodynamic type metric. An essential foundation for the metric is a complete equation of state including all extensive variables of the system; examples are given. Finally, the second law of thermodynamics imposes convexity on any equation of state, be it analytical or empirical.
Lorentzian Einstein metrics with prescribed conformal infinity
Enciso, Alberto
2014-01-01
We prove that there are asymptotically anti-de Sitter Einstein metrics with prescribed conformal infinity. More precisely we show that, given any suitably small perturbation $\\hat g$ of the conformal metric of the $(n+1)$-dimensional anti-de Sitter space at timelike infinity, which is given by the canonical Lorentzian metric on the $n$-dimensional cylinder, there is a Lorentzian Einstein metric on $(-T,T)\\times \\mathbb{B}^n$ whose conformal geometry is given by $\\hat g$. This is a Lorentzian counterpart of the Graham-Lee theorem in Riemannian geometry and is motivated by the holographic prescription problem in the context of the AdS/CFT correspondence in string theory.
Thermodynamic motivations of spherically symmetric static metrics
Moradpour, H
2015-01-01
Bearing the thermodynamic arguments together with the two definitions of mass in mind, we try to find metrics with spherical symmetry. We consider the adiabatic condition along with the Gong-Wang mass, and evaluate the $g_{rr}$ element which points to a null hypersurface. In addition, we generalize the thermodynamics laws to this hypersurface to find its temperature and thus the corresponding surface gravity which enables us to get a relation for the $g_{tt}$ element. Finally, we investigate the mathematical and physical properties of the discovered metric in the Einstein relativity framework which shows that the primary mentioned null hypersurface is an event horizon. We also show that if one considers the Misner-Sharp mass in the calculations, the Schwarzschild metric will be got. The relationship between the two mass definitions in each metric is studied. The results of considering the geometrical surface gravity are also addressed.
Clean Cities Annual Metrics Report 2009 (Revised)
Energy Technology Data Exchange (ETDEWEB)
Johnson, C.
2011-08-01
Document provides Clean Cities coalition metrics about the use of alternative fuels; the deployment of alternative fuel vehicles, hybrid electric vehicles (HEVs), and idle reduction initiatives; fuel economy activities; and programs to reduce vehicle miles driven.
Business model metrics: an open repository
Heikkila, M.; Bouwman, W.A.G.A.; Heikkila, J; Solaimani, S.; Janssen, W
2015-01-01
Development of successful business models has become a necessity in turbulent business environments, but compared to research on business modeling tools, attention to the role of metrics in designing business models in literature is limited. Building on existing approaches to business models and performance measurement literature, we develop a generic open repository of metrics related to core business model concepts. We validate and assess the practical value of the repository based on four ...
Multipole solutions in metric-affine gravity
Socorro, J; Macías, A; Mielke, E W; Socorro, José; Lämmerzahl, Claus; Macías, Alfredo; Mielke, Eckehard W.
1998-01-01
Above Planck energies, the spacetime might become non--Riemannian, as it is known fron string theory and inflation. Then geometries arise in which nonmetricity and torsion appear as field strengths, side by side with curvature. By gauging the affine group, a metric affine gauge theory emerges as dynamical framework. Here, by using the harmonic map ansatz, a new class of multipole like solutions in the metric affine gravity theory (MAG) is obtained.
Metric Diophantine approximation on homogeneous varieties
Ghosh, Anish; Nevo, Amos
2012-01-01
We develop the metric theory of Diophantine approximation on homogeneous varieties of semisimple algebraic groups and prove results analogous to the classical Khinchin and Jarnik theorems. In full generality our results establish simultaneous Diophantine approximation with respect to several completions, and Diophantine approximation over general number fields using S-algebraic integers. In several important examples, the metric results we obtain are optimal. The proof uses quantitative equidistribution properties of suitable averaging operators, which are derived from spectral bounds in automorphic representations.
Canonical metrics on Cartan--Hartogs domains
Zedda, Michela
2011-01-01
In this paper we address two problems concerning a family of domains $M_{\\Omega}(\\mu) \\subset \\C^n$, called Cartan-Hartogs domains, endowed with a natural Kaehler metric $g(\\mu)$. The first one is determining when the metric $g(\\mu)$ is extremal (in the sense of Calabi), while the second one studies when the coefficient $a_2$ in the Engli\\v{s} expansion of Rawnsley $\\epsilon$-function associated to $g(\\mu)$ is constant.
METRICS IN ORGANIZATIONAL CENTRALIZATION AND DECENTRALIZATION
Vladimir Modrak; Sorin Mihai Radu; Jan Modrak
2014-01-01
Continual improvement of business processes requires, apart from other efforts, to develop effective metrics, by which managers and/or process engineers will be able to manage the organization's growth. Obviously, there are plenty measures that can be taken to optimize processes. Once effective metrics are identified, the assessment team should do what works best for them. In this paper, an organizational “centralization” or “decentralization” is a matter of interest. The dichotomous term “ce...
Modeling Languages: metrics and assessing tools
Fonte, Daniela; Boas, Ismael Vilas; Azevedo, José; Peixoto, José João; Faria, Pedro; Silva, Pedro; Sá, Tiago de, 1990-; Costa, Ulisses; da Cruz, Daniela; Henriques, Pedro Rangel
2012-01-01
Any traditional engineering field has metrics to rigorously assess the quality of their products. Engineers know that the output must satisfy the requirements, must comply with the production and market rules, and must be competitive. Professionals in the new field of software engineering started a few years ago to define metrics to appraise their product: individual programs and software systems. This concern motivates the need to assess not only the outcome but also the process and tools em...
GRC GSFC TDRSS Waveform Metrics Report
Mortensen, Dale J.
2013-01-01
The report presents software metrics and porting metrics for the GGT Waveform. The porting was from a ground-based COTS SDR, the SDR-3000, to the CoNNeCT JPL SDR. The report does not address any of the Operating Environment (OE) software development, nor the original TDRSS waveform development at GSFC for the COTS SDR. With regard to STRS, the report presents compliance data and lessons learned.
Constrained Metric Learning by Permutation Inducing Isometries.
Bosveld, Joel; Mahmood, Arif; Huynh, Du Q; Noakes, Lyle
2016-01-01
The choice of metric critically affects the performance of classification and clustering algorithms. Metric learning algorithms attempt to improve performance, by learning a more appropriate metric. Unfortunately, most of the current algorithms learn a distance function which is not invariant to rigid transformations of images. Therefore, the distances between two images and their rigidly transformed pair may differ, leading to inconsistent classification or clustering results. We propose to constrain the learned metric to be invariant to the geometry preserving transformations of images that induce permutations in the feature space. The constraint that these transformations are isometries of the metric ensures consistent results and improves accuracy. Our second contribution is a dimension reduction technique that is consistent with the isometry constraints. Our third contribution is the formulation of the isometry constrained logistic discriminant metric learning (IC-LDML) algorithm, by incorporating the isometry constraints within the objective function of the LDML algorithm. The proposed algorithm is compared with the existing techniques on the publicly available labeled faces in the wild, viewpoint-invariant pedestrian recognition, and Toy Cars data sets. The IC-LDML algorithm has outperformed existing techniques for the tasks of face recognition, person identification, and object classification by a significant margin.
Dynamical Systems on Spectral Metric Spaces
Bellissard, Jean V; Reihani, Kamran
2010-01-01
Let (A,H,D) be a spectral triple, namely: A is a C*-algebra, H is a Hilbert space on which A acts and D is a selfadjoint operator with compact resolvent such that the set of elements of A having a bounded commutator with D is dense. A spectral metric space, the noncommutative analog of a complete metric space, is a spectral triple (A,H,D) with additional properties which guaranty that the Connes metric induces the weak*-topology on the state space of A. A *-automorphism respecting the metric defined a dynamical system. This article gives various answers to the question: is there a canonical spectral triple based upon the crossed product algebra AxZ, characterizing the metric properties of the dynamical system ? If $\\alpha$ is the noncommutative analog of an isometry the answer is yes. Otherwise, the metric bundle construction of Connes and Moscovici is used to replace (A,$\\alpha$) by an equivalent dynamical system acting isometrically. The difficulties relating to the non compactness of this new system are di...
Positive Semidefinite Metric Learning with Boosting
Shen, Chunhua; Wang, Lei; Hengel, Anton van den
2009-01-01
The learning of appropriate distance metrics is a critical problem in image classification and retrieval. In this work, we propose a boosting-based technique, termed \\BoostMetric, for learning a Mahalanobis distance metric. One of the primary difficulties in learning such a metric is to ensure that the Mahalanobis matrix remains positive semidefinite. Semidefinite programming is sometimes used to enforce this constraint, but does not scale well. \\BoostMetric is instead based on a key observation that any positive semidefinite matrix can be decomposed into a linear positive combination of trace-one rank-one matrices. \\BoostMetric thus uses rank-one positive semidefinite matrices as weak learners within an efficient and scalable boosting-based learning process. The resulting method is easy to implement, does not require tuning, and can accommodate various types of constraints. Experiments on various datasets show that the proposed algorithm compares favorably to those state-of-the-art methods in terms of classi...
Isometry groups of proper metric spaces
Niemiec, Piotr
2012-01-01
Given a locally compact Polish space X, a necessary and sufficient condition for a group G of homeomorphisms of X to be the full isometry group of (X,d) for some proper metric d on X is given. It is shown that every locally compact Polish group G acts freely on GxY as the full isometry group of GxY with respect to a certain proper metric on GxY, where Y is an arbitrary locally compact Polish space with (card(G),card(Y)) different from (1,2). Locally compact Polish groups which act effectively and almost transitively on complete metric spaces as full isometry groups are characterized. Locally compact Polish non-Abelian groups on which every left invariant metric is automatically right invariant are characterized and fully classified. It is demonstrated that for every locally compact Polish space X having more than two points the set of proper metrics d such that Iso(X,d) = {id} is dense in the space of all proper metrics on X.
Bi-metric pseudo-Finslerian spacetimes
Skakala, Jozef; Visser, Matt
2011-08-01
Finsler spacetimes have become increasingly popular within the theoretical physics community over the last two decades. However, because physicists need to use pseudo-Finsler structures to describe propagation of signals, there will be nonzero null vectors in both the tangent and cotangent spaces — this causes significant problems in that many of the mathematical results normally obtained for "usual" (Euclidean signature) Finsler structures either do not apply, or require significant modifications to their formulation and/or proof. We shall first provide a few basic definitions, explicitly demonstrating the interpretation of bi-metric theories in terms of pseudo-Finsler norms. We shall then discuss the tricky issues that arise when trying to construct an appropriate pseudo-Finsler metric appropriate to bi-metric spacetimes. Whereas in Euclidian signature the construction of the Finsler metric typically fails only at the zero vector, in Lorentzian signature the Finsler metric is typically ill-defined on the entire null cone. Consequently it is not a good idea to try to encode bi-metricity into pseudo-Finsler geometry. One has to be very careful when applying the concept of pseudo-Finsler geometry in physics.
Yu, Chung-huang; Hung, Yu-Cheng; Lin, Yang-Hua; Chen, Guan-Xun; Wei, Shun-Hwa; Huang, Chang-Hung; Chen, Chen-Sheng
2014-09-01
A solid-ankle cushioned heel (SACH) foot is a non-joint foot without natural ankle function. Trans-tibial amputees may occur toe scuffing in the late swing phase due to a lack of active dorsiflexion. To address this problem, clinical guidelines suggests shortening the pylon to produce a smooth gait. However, this causes a leg length discrepancy, induces asymmetry in the hip joint, and causes an overload of L5/S1 joint force. Therefore, this study aimed to investigate the influence of different prosthesis pylons on the hip joint and L5/S1 joint forces. Ten subjects were recruited using leg length for normalisation. Four different pylon reductions (0%, 1%, 2%, and 3%) were used for gait analysis. A Vicon system and force plates were used to collect kinematic data and ground reaction force, respectively. The software package MATLAB was used to create a mathematical model for evaluating the symmetry and force of the hip joint and the low back force of the L5/S1 joint. The model was validated by the correlation coefficient (CC=0.947) and root mean square (RMS=0.028 BW). The model estimated that the 1% group had a symmetrical hip joint force and a lower L5/S1 joint force in the vertical direction. This study indicates that a 1% pylon shortening on a SACH prosthesis is appropriate for a trans-tibial amputee.
金融衍生品案例研究：高盛金融欺诈案%Case Study of Financial Derivatives: Fraud Action of Goldman Sachs
Institute of Scientific and Technical Information of China (English)
李欣婷; 闫妍; 薛欣
2012-01-01
The United States Securities and Exchange Commission brings the securities fraud action against Goldman Sachs, for making materially misleading statements and commissions in connection with a synthetic eollateralized debt obligation ("CDO") Goldman Sachs structured and marketed to investors. This CDO product whose name is ABACUS 2007-AC1 led to a great loss to the investors. This paper mainly analyzes the structures and risk features of three derivative products including RMBS, CDS and CDO. Based on the valuation formula, the reason of ABACUS 2007-AC1 depreciation is explained.%高盛集团因金融欺诈被美国证券交易委员会起诉，原因是高盛集团在销售一款合成担保债务凭证ABACUS2007-AC1时有误导性陈述，导致投资者巨额亏损。本文重点对案例中涉及的金融衍生品——RMBS、CDS和CDO的结构和风险特征进行分析，并结合CDO定价公式，对ABACUS2007-AC1的价值下跌进行定量的分析。
Ko, Sang-Hun; Cha, Jae-Ryong; Lee, Chae-Chil; Hwang, Il-Yeong; Choe, Chang-Gyu; Kim, Min-Seok
2016-12-01
Recurrence of glenohumeral dislocation after arthroscopic Bankart repair can be associated with a large osseous defect in the posterosuperior part of the humeral head. Our hypothesis is that remplissage is more effective to prevent recurrence of glenohumeral instability without a severe motion deficit. Engaging Hill-Sachs lesions were observed in 48 of 737 patients (6.5%). Twenty-four patients underwent arthroscopic Bankart repair combined with remplissage (group I) and the other 24 patients underwent arthroscopic Bankart repair alone (group II). Clinical outcomes were prospectively evaluated by assessing the range of motion. Complications, recurrence rates, and functional results were assessed utilizing the American Shoulder and Elbow Surgeons (ASES) score, Rowe score, and the Korean Shoulder Score for Instability (KSSI) score. Capsulotenodesis healing after remplissage was evaluated with magnetic resonance imaging. The average ASES, Rowe, and KSSI scores were statistically significantly higher in group I than group II. The frequency of recurrence was statistically significantly higher in group II. The average loss in external rotation measured with the arm positioned at the side of the trunk was greater in group II and that in abduction was also higher in group II. Compared to single arthroscopic Bankart repair, the remplissage procedure combined with arthroscopic Bankart repair was more effective to prevent the recurrence of anterior shoulder instability without significant impact on shoulder mobility in patients who had huge Hill-Sachs lesions.
Bielby, Rich; Shanks, T.; Sawangwit, U.; Croom, S. M.; Ross, Nicholas P.; Wake, D. A.
2010-04-01
We investigate the use of simple colour cuts applied to the Sloan Digital Sky Survey (SDSS) optical imaging to perform photometric selections of emission-line galaxies (ELGs) out to z S11). We thus perform colour cuts using the SDSS g, r and i bands and obtain mean photometric redshifts of and . We further calibrate our high-redshift selection using spectroscopic observations with the AAOmega spectrograph on the 4-m Anglo-Australian Telescope, observing ~50-200 galaxy candidates in four separate fields. With just 1h of integration time and seeing of ~ 1.6arcsec, we successfully determined redshifts for ~65 per cent of the targeted candidates. We compare our spectroscopic redshifts to the photometric redshifts from the COMBO-17 survey and find reasonable agreement between the two. We calculate the angular correlation functions of these samples and find correlation lengths of r0 = 2.78 +/- 0.08, 3.71 +/- 0.11 and 5.50 +/- 0.13h-1Mpc for the low-, mid- and high-redshift samples, respectively. Comparing these results with predicted dark matter clustering, we estimate the bias parameter for each sample to be b = 0.72 +/- 0.02, b = 0.93 +/- 0.03 and b = 1.43 +/- 0.03. We calculate the two-point redshift-space autocorrelation function at z ~ 0.6 and find a clustering amplitude of so = 6.4 +/- 0.8h-1Mpc. Finally, we use our photometric sample to search for the integrated Sachs-Wolfe signal in the Wilkinson Microwave Anisotropy Probe (WMAP) 5-yr data. We cross-correlate our three redshift samples with the WMAP W, V, Q and K bands and find an overall trend for a positive signal similar to that expected from models. However, the signal in each is relatively weak, with the results in the WMAP W band being wTg(<100arcmin) = 0.25 +/- 0.27, 0.17 +/- 0.20 and 0.17 +/- 0.16μK for the low-, mid- and high-redshift samples, respectively. Combining all three galaxy samples, we find a signal of wTg(<100arcmin) = 0.20 +/- 0.12μK in the WMAP W band, a significance of 1.7σ. However, in
Karpati, Mazal; Gazit, Ephraim; Goldman, Boleslaw; Frisch, Amos; Colombo, Roberto; Peleg, Leah
2004-02-01
The incidence of Tay-Sachs disease (TSD) carriers, as defined by enzyme assay, is 1:29 among Ashkenazi Jews and 1:110 among Moroccan Jews. An elevated carrier frequency of 1:140 was also observed in the Iraqi Jews (IJ), while in other Israeli populations the world's pan-ethnic frequency of approximately 1:280 has been found. Recently a novel mutation, G749T, has been reported in 38.7% of the IJ carriers (24/62). Here we report a second novel HEXA mutation specific to the IJ TDS carriers: a substitution of cytosine 1351 by guanosine (C1351G), resulting in the change of leucine to valine in position 451. This mutation was found in 33.9% (21/62) of the carriers and in none of 100 non-carrier IJ. In addition to the two specific mutations, 14.5% (9/62) of the IJ carriers bear a known "Jewish" mutation (Ashkenazi or Moroccan) and 11.3% (7/62) carry a known "non-Jewish" mutation. In 1 DNA sample no mutation has yet been detected. To investigate the genetic history of the IJ-specific mutations (C1351G and G749T), the allelic distribution of four polymorphic markers (D15S131, D15S1025, D15S981, D15S1050) was analyzed in IJ heterozygotes and ethnically matched controls. Based on linkage disequilibrium, recombination factor (theta) between the markers and mutated loci, and the population growth correction, we deduced that G749T occurred in a founder ancestor 44.8 +/- 14.2 generations (g) ago [95% confidence interval (CI) 17.0-72.6 g] and C1351G arose 80.4 +/- 35.9 g ago (95% CI 44.5-116.3 g). Thus, the estimated dates for introduction of mutations are: 626 +/- 426 A.D. (200-1052 A.D.) for G749T and 442 +/- 1077 B.C. (1519 B.C. to 635 A.D.) for C1351G.
Flowing liquid crystal simulating the Schwarzschild metric
Energy Technology Data Exchange (ETDEWEB)
Pereira, Erms R.; Moraes, Fernando [Universidade Federal da Paraiba (UFPB), Joao Pessoa, PB (Brazil)
2009-07-01
Full text. We show how to simulate the equatorial section of the Schwarzschild metric through a flowing liquid crystal in its nematic phase. Inside a liquid crystal in the nematic phase, a traveling light ray feels an effective metric, whose properties are linked to perpendicular and parallel refractive indexes, no e ne respectively, of the rod-like molecule of the liquid crystal. As these indexes depend on the scalar order parameter of the liquid crystal, the Beris-Edwards hydrodynamic theory is used to connect the order parameter with the velocity of a liquid crystal flow at each point. This way we calculate a radial velocity profile that simulates the equatorial section of the Schwarzschild metric in the nematic phase of the liquid crystal. This work will be presented in the following way. First, we show the effective metric that describes the light propagation around a (k = 1; c = 0) disclination defect of the nematic phase of a liquid crystalline sample and how this light propagation can be described by the order parameter q of the liquid crystalline material. Afterwards, we consider the liquid crystal flowing radially and we use the Beris-Edwards theory to analyze the dependence of the order parameter of the material with the flowing velocity module. In these two cases we consider the more general situation of three space dimensions. Finally, we employ the result from the second part in the first and we compare with the Schwarzschild metric written in isotropic coordinates. (author)
Future of the PCI Readmission Metric.
Wasfy, Jason H; Yeh, Robert W
2016-03-01
Between 2013 and 2014, the Centers for Medicare and Medicaid Services and the National Cardiovascular Data Registry publically reported risk-adjusted 30-day readmission rates after percutaneous coronary intervention (PCI) as a pilot project. A key strength of this public reporting effort included risk adjustment with clinical rather than administrative data. Furthermore, because readmission after PCI is common, expensive, and preventable, this metric has substantial potential to improve quality and value in American cardiology care. Despite this, concerns about the metric exist. For example, few PCI readmissions are caused by procedural complications, limiting the extent to which improved procedural technique can reduce readmissions. Also, similar to other readmission measures, PCI readmission is associated with socioeconomic status and race. Accordingly, the metric may unfairly penalize hospitals that care for underserved patients. Perhaps in the context of these limitations, Centers for Medicare and Medicaid Services has not yet included PCI readmission among metrics that determine Medicare financial penalties. Nevertheless, provider organizations may still wish to focus on this metric to improve value for cardiology patients. PCI readmission is associated with low-risk chest discomfort and patient anxiety. Therefore, patient education, improved triage mechanisms, and improved care coordination offer opportunities to minimize PCI readmissions. Because PCI readmission is common and costly, reducing PCI readmission offers provider organizations a compelling target to improve the quality of care, and also performance in contracts involve shared financial risk.
Implementing the Data Center Energy Productivity Metric
Energy Technology Data Exchange (ETDEWEB)
Sego, Landon H.; Marquez, Andres; Rawson, Andrew; Cader, Tahir; Fox, Kevin M.; Gustafson, William I.; Mundy, Christopher J.
2012-10-01
As data centers proliferate in both size and number, their energy efficiency is becoming increasingly important. We discuss the properties of a number of the proposed metrics of energy efficiency and productivity. In particular, we focus on the Data Center Energy Productivity (DCeP) metric, which is the ratio of useful work produced by the data center to the energy consumed performing that work. We describe our approach for using DCeP as the principal outcome of a designed experiment using a highly instrumented, high performance computing data center. We found that DCeP was successful in clearly distinguishing between different operational states in the data center, thereby validating its utility as a metric for identifying configurations of hardware and software that would improve (or even maximize) energy productivity. We also discuss some of the challenges and benefits associated with implementing the DCeP metric, and we examine the efficacy of the metric in making comparisons within a data center and among data centers.
Cleanroom Energy Efficiency: Metrics and Benchmarks
Energy Technology Data Exchange (ETDEWEB)
International SEMATECH Manufacturing Initiative; Mathew, Paul A.; Tschudi, William; Sartor, Dale; Beasley, James
2010-07-07
Cleanrooms are among the most energy-intensive types of facilities. This is primarily due to the cleanliness requirements that result in high airflow rates and system static pressures, as well as process requirements that result in high cooling loads. Various studies have shown that there is a wide range of cleanroom energy efficiencies and that facility managers may not be aware of how energy efficient their cleanroom facility can be relative to other cleanroom facilities with the same cleanliness requirements. Metrics and benchmarks are an effective way to compare one facility to another and to track the performance of a given facility over time. This article presents the key metrics and benchmarks that facility managers can use to assess, track, and manage their cleanroom energy efficiency or to set energy efficiency targets for new construction. These include system-level metrics such as air change rates, air handling W/cfm, and filter pressure drops. Operational data are presented from over 20 different cleanrooms that were benchmarked with these metrics and that are part of the cleanroom benchmark dataset maintained by Lawrence Berkeley National Laboratory (LBNL). Overall production efficiency metrics for cleanrooms in 28 semiconductor manufacturing facilities in the United States and recorded in the Fabs21 database are also presented.
SOFTWARE METRICS VALIDATION METHODOLOGIES IN SOFTWARE ENGINEERING
Directory of Open Access Journals (Sweden)
K.P. Srinivasan
2014-12-01
Full Text Available In the software measurement validations, assessing the validation of software metrics in software engineering is a very difficult task due to lack of theoretical methodology and empirical methodology [41, 44, 45]. During recent years, there have been a number of researchers addressing the issue of validating software metrics. At present, software metrics are validated theoretically using properties of measures. Further, software measurement plays an important role in understanding and controlling software development practices and products. The major requirement in software measurement is that the measures must represent accurately those attributes they purport to quantify and validation is critical to the success of software measurement. Normally, validation is a collection of analysis and testing activities across the full life cycle and complements the efforts of other quality engineering functions and validation is a critical task in any engineering project. Further, validation objective is to discover defects in a system and assess whether or not the system is useful and usable in operational situation. In the case of software engineering, validation is one of the software engineering disciplines that help build quality into software. The major objective of software validation process is to determine that the software performs its intended functions correctly and provides information about its quality and reliability. This paper discusses the validation methodology, techniques and different properties of measures that are used for software metrics validation. In most cases, theoretical and empirical validations are conducted for software metrics validations in software engineering [1-50].
Metric for Estimating Congruity between Quantum Images
Directory of Open Access Journals (Sweden)
Abdullah M. Iliyasu
2016-10-01
Full Text Available An enhanced quantum-based image fidelity metric, the QIFM metric, is proposed as a tool to assess the “congruity” between two or more quantum images. The often confounding contrariety that distinguishes between classical and quantum information processing makes the widely accepted peak-signal-to-noise-ratio (PSNR ill-suited for use in the quantum computing framework, whereas the prohibitive cost of the probability-based similarity score makes it imprudent for use as an effective image quality metric. Unlike the aforementioned image quality measures, the proposed QIFM metric is calibrated as a pixel difference-based image quality measure that is sensitive to the intricacies inherent to quantum image processing (QIP. As proposed, the QIFM is configured with in-built non-destructive measurement units that preserve the coherence necessary for quantum computation. This design moderates the cost of executing the QIFM in order to estimate congruity between two or more quantum images. A statistical analysis also shows that our proposed QIFM metric has a better correlation with digital expectation of likeness between images than other available quantum image quality measures. Therefore, the QIFM offers a competent substitute for the PSNR as an image quality measure in the quantum computing framework thereby providing a tool to effectively assess fidelity between images in quantum watermarking, quantum movie aggregation and other applications in QIP.
Homology-independent metrics for comparative genomics.
Coutinho, Tarcisio José Domingos; Franco, Glória Regina; Lobo, Francisco Pereira
2015-01-01
A mainstream procedure to analyze the wealth of genomic data available nowadays is the detection of homologous regions shared across genomes, followed by the extraction of biological information from the patterns of conservation and variation observed in such regions. Although of pivotal importance, comparative genomic procedures that rely on homology inference are obviously not applicable if no homologous regions are detectable. This fact excludes a considerable portion of "genomic dark matter" with no significant similarity - and, consequently, no inferred homology to any other known sequence - from several downstream comparative genomic methods. In this review we compile several sequence metrics that do not rely on homology inference and can be used to compare nucleotide sequences and extract biologically meaningful information from them. These metrics comprise several compositional parameters calculated from sequence data alone, such as GC content, dinucleotide odds ratio, and several codon bias metrics. They also share other interesting properties, such as pervasiveness (patterns persist on smaller scales) and phylogenetic signal. We also cite examples where these homology-independent metrics have been successfully applied to support several bioinformatics challenges, such as taxonomic classification of biological sequences without homology inference. They where also used to detect higher-order patterns of interactions in biological systems, ranging from detecting coevolutionary trends between the genomes of viruses and their hosts to characterization of gene pools of entire microbial communities. We argue that, if correctly understood and applied, homology-independent metrics can add important layers of biological information in comparative genomic studies without prior homology inference.
Codes in W*-Metric Spaces: Theory and Examples
Bumgardner, Christopher J.
2011-01-01
We introduce a "W*"-metric space, which is a particular approach to non-commutative metric spaces where a "quantum metric" is defined on a von Neumann algebra. We generalize the notion of a quantum code and quantum error correction to the setting of finite dimensional "W*"-metric spaces, which includes codes and error correction for classical…
g-Weak Contraction in Ordered Cone Rectangular Metric Spaces
Directory of Open Access Journals (Sweden)
S. K. Malhotra
2013-01-01
Full Text Available We prove some common fixed-point theorems for the ordered g-weak contractions in cone rectangular metric spaces without assuming the normality of cone. Our results generalize some recent results from cone metric and cone rectangular metric spaces into ordered cone rectangular metric spaces. Examples are provided which illustrate the results.
Demonstration of the Symmetry Properties of Gravitational Metric Fields
Institute of Scientific and Technical Information of China (English)
邵亮; H.NODA; 邵丹; 邵常贵
2002-01-01
We calculate some Wilson loop functionals in a static sphere-symmetrical diagonal metric field and a gravitational metric field established by a cosmic string. Using the direction change of vector when it is parallel transported in the metric field of cosmic string, the cone symmetry of the metric field is shown.
34 CFR 74.15 - Metric system of measurement.
2010-07-01
... 34 Education 1 2010-07-01 2010-07-01 false Metric system of measurement. 74.15 Section 74.15... Metric system of measurement. The Metric Conversion Act, as amended by the Omnibus Trade and Competitiveness Act (15 U.S.C. 205) declares that the metric system is the preferred measurement system for...
When is a metric not a metric? Remarks on direct curve comparison in bioequivalence studies.
Jawień, Wojciech
2009-06-01
The majority of measures proposed to date for direct curve comparison in bioequivalence studies were investigated. These measures have often been called metrics, but in most cases this was incorrect in the mathematical sense. It was demonstrated, with a set of counter-examples, that the axioms of a metric are fulfilled only for the integral p-metric and some of its transforms. The Rescigno index and two other measures devised by Polli and McLean are the semi-metrics, lacking the triangle inequality, while others also lack symmetry. The use of the p-metric is therefore recommended, and statistical analysis is suggested as a point at which the scaling of differences might be carried out.
Single Kerr-Schild metrics: a double view
Energy Technology Data Exchange (ETDEWEB)
McIntosh, C.B.G.; Hickman, M.S.
1988-08-01
Real-vacuum single Kerr-Schild (ISKS) metrics are discussed and new results proved. It is shown that if they Weyl tensor of such a metric has a twist-free expanding principal null direction, then it belongs to the Schwarzchild family of metrics-there are no Petrov type-II Robinson-Trautman metrics of Kerr-Schild type. If such a metric has twist then it belongs either to the Kerr family or else its Weyl tensor is of Petrov type II. The main part of the paper is concerned with complexified versions of Kerr-Schild metrics. The general real ISKS metric is written in double Kerr-Schild (IDKS) form. The H and l potentials which generate IDKS metrics are determined for the general vacuum ISKS metric and given explicitly for the Schwarzchild and Kerr families of metrics.
Evaluating and Estimating the WCET Criticality Metric
DEFF Research Database (Denmark)
Jordan, Alexander
2014-01-01
Static analysis tools that are used for worst-case execution time (WCET) analysis of real-time software just provide partial information on an analyzed program. Only the longest-executing path, which currently determines the WCET bound is indicated to the programmer. This limited view can prevent...... a programmer (or compiler) from targeting optimizations the right way. A possible resort is to use a metric that targets WCET and which can be efficiently computed for all code parts of a program. Similar to dynamic profiling techniques, which execute code with input that is typically expected...... to estimate the Criticality metric, by relaxing the precision of WCET analysis. Through this, we can reduce analysis time by orders of magnitude, while only introducing minor error. To evaluate our estimation approach and share our garnered experience using the metric, we evaluate real-time programs, which...
SOCIAL METRICS APPLIED TO SMART TOURISM
Directory of Open Access Journals (Sweden)
O. Cervantes
2016-09-01
Full Text Available We present a strategy to make productive use of semantically-related social data, from a user-centered semantic network, in order to help users (tourists and citizens in general to discover cultural heritage, points of interest and available services in a smart city. This data can be used to personalize recommendations in a smart tourism application. Our approach is based on flow centrality metrics typically used in social network analysis: flow betweenness, flow closeness and eccentricity. These metrics are useful to discover relevant nodes within the network yielding nodes that can be interpreted as suggestions (venues or services to users. We describe the semantic network built on graph model, as well as social metrics algorithms used to produce recommendations. We also present challenges and results from a prototypical implementation applied to the case study of the City of Puebla, Mexico.
Social Metrics Applied to Smart Tourism
Cervantes, O.; Gutiérrez, E.; Gutiérrez, F.; Sánchez, J. A.
2016-09-01
We present a strategy to make productive use of semantically-related social data, from a user-centered semantic network, in order to help users (tourists and citizens in general) to discover cultural heritage, points of interest and available services in a smart city. This data can be used to personalize recommendations in a smart tourism application. Our approach is based on flow centrality metrics typically used in social network analysis: flow betweenness, flow closeness and eccentricity. These metrics are useful to discover relevant nodes within the network yielding nodes that can be interpreted as suggestions (venues or services) to users. We describe the semantic network built on graph model, as well as social metrics algorithms used to produce recommendations. We also present challenges and results from a prototypical implementation applied to the case study of the City of Puebla, Mexico.
Metric learning for automatic sleep stage classification.
Phan, Huy; Do, Quan; Do, The-Luan; Vu, Duc-Lung
2013-01-01
We introduce in this paper a metric learning approach for automatic sleep stage classification based on single-channel EEG data. We show that learning a global metric from training data instead of using the default Euclidean metric, the k-nearest neighbor classification rule outperforms state-of-the-art methods on Sleep-EDF dataset with various classification settings. The overall accuracy for Awake/Sleep and 4-class classification setting are 98.32% and 94.49% respectively. Furthermore, the superior accuracy is achieved by performing classification on a low-dimensional feature space derived from time and frequency domains and without the need for artifact removal as a preprocessing step.
Robust Metric Learning by Smooth Optimization
Huang, Kaizhu; Xu, Zenglin; Liu, Cheng-Lin
2012-01-01
Most existing distance metric learning methods assume perfect side information that is usually given in pairwise or triplet constraints. Instead, in many real-world applications, the constraints are derived from side information, such as users' implicit feedbacks and citations among articles. As a result, these constraints are usually noisy and contain many mistakes. In this work, we aim to learn a distance metric from noisy constraints by robust optimization in a worst-case scenario, to which we refer as robust metric learning. We formulate the learning task initially as a combinatorial optimization problem, and show that it can be elegantly transformed to a convex programming problem. We present an efficient learning algorithm based on smooth optimization [7]. It has a worst-case convergence rate of O(1/{\\surd}{\\varepsilon}) for smooth optimization problems, where {\\varepsilon} is the desired error of the approximate solution. Finally, our empirical study with UCI data sets demonstrate the effectiveness of ...
Rainbow Rindler metric and Unruh effect
Yadav, Gaurav; Majhi, Bibhas Ranjan
2016-01-01
The energy of a particle moving on a spacetime, in principle, can affect the background metric. The modifications to it depend on the ratio of energy of the particle and the Planck energy, known as rainbow gravity. Here we find the explicit expressions for the coordinate transformations from rainbow Minkowski spacetime to accelerated frame. The corresponding metric is also obtained which we call as rainbow-Rindler metric. So far we are aware of, no body has done it in a concrete manner. Here this is found from the first principle and hence all the parameters are properly identified. The advantage of this is that the calculated Unruh temperature is compatible with the Hawking temperature of the rainbow black hole horizon, obtained earlier. Since the accelerated frame has several importance in revealing various properties of gravity, we believe that the present result will not only fill that gap, but also help to explore different aspects of rainbow gravity paradigm.
Enhanced Accident Tolerant LWR Fuels: Metrics Development
Energy Technology Data Exchange (ETDEWEB)
Shannon Bragg-Sitton; Lori Braase; Rose Montgomery; Chris Stanek; Robert Montgomery; Lance Snead; Larry Ott; Mike Billone
2013-09-01
The Department of Energy (DOE) Fuel Cycle Research and Development (FCRD) Advanced Fuels Campaign (AFC) is conducting research and development on enhanced Accident Tolerant Fuels (ATF) for light water reactors (LWRs). This mission emphasizes the development of novel fuel and cladding concepts to replace the current zirconium alloy-uranium dioxide (UO2) fuel system. The overall mission of the ATF research is to develop advanced fuels/cladding with improved performance, reliability and safety characteristics during normal operations and accident conditions, while minimizing waste generation. The initial effort will focus on implementation in operating reactors or reactors with design certifications. To initiate the development of quantitative metrics for ATR, a LWR Enhanced Accident Tolerant Fuels Metrics Development Workshop was held in October 2012 in Germantown, MD. This paper summarizes the outcome of that workshop and the current status of metrics development for LWR ATF.
Development of testing metrics for military robotics
Resendes, Raymond J.
1993-05-01
The use of robotics or unmanned systems offers significant benefits to the military user by enhancing mobility, logistics, material handling, command and control, reconnaissance, and protection. The evaluation and selection process for the procurement of an unmanned robotic system involves comparison of performance and physical characteristics such as operating environment, application, payloads and performance criteria. Testing an unmanned system for operation in an unstructured environment using emerging technologies, which have not yet been fully tested, presents unique challenges for the testing community. Standard metrics, test procedures, terminologies, and methodologies simplify comparison of different systems. A procedure was developed to standardize the test and evaluation process for UGVs. This procedure breaks the UGV into three components: the platform, the payload, and the command and control link. Standardized metrics were developed for these components which permit unbiased comparison of different systems. The development of these metrics and their application will be presented.
Dissertation: Geodesics of Random Riemannian Metrics
LaGatta, Tom
2011-01-01
We introduce Riemannian First-Passage Percolation (Riemannian FPP) as a new model of random differential geometry, by considering a random, smooth Riemannian metric on $\\mathbb R^d$. We are motivated in our study by the random geometry of first-passage percolation (FPP), a lattice model which was developed to model fluid flow through porous media. By adapting techniques from standard FPP, we prove a shape theorem for our model, which says that large balls under this metric converge to a deterministic shape under rescaling. As a consequence, we show that smooth random Riemannian metrics are geodesically complete with probability one. In differential geometry, geodesics are curves which locally minimize length. They need not do so globally: consider great circles on a sphere. For lattice models of FPP, there are many open questions related to minimizing geodesics; similarly, it is interesting from a geometric perspective when geodesics are globally minimizing. In the present study, we show that for any fixed st...
Metric Learning for Hyperspectral Image Segmentation
Bue, Brian D.; Thompson, David R.; Gilmore, Martha S.; Castano, Rebecca
2011-01-01
We present a metric learning approach to improve the performance of unsupervised hyperspectral image segmentation. Unsupervised spatial segmentation can assist both user visualization and automatic recognition of surface features. Analysts can use spatially-continuous segments to decrease noise levels and/or localize feature boundaries. However, existing segmentation methods use tasks-agnostic measures of similarity. Here we learn task-specific similarity measures from training data, improving segment fidelity to classes of interest. Multiclass Linear Discriminate Analysis produces a linear transform that optimally separates a labeled set of training classes. The defines a distance metric that generalized to a new scenes, enabling graph-based segmentation that emphasizes key spectral features. We describe tests based on data from the Compact Reconnaissance Imaging Spectrometer (CRISM) in which learned metrics improve segment homogeneity with respect to mineralogical classes.
Metric perturbations in Einstein-Cartan Cosmology
Garcia de Andrade, L C
2002-01-01
Metric perturbations the stability of solution of Einstein-Cartan cosmology (ECC) are given. The first addresses the stability of solutions of Einstein-Cartan (EC) cosmological model against Einstein static universe background. In this solution we show that the metric is stable against first-order perturbations and correspond to acoustic oscillations. The second example deals with the stability of de Sitter metric also against first-order perturbations. Torsion and shear are also computed in these cases. The resultant perturbed anisotropic spacetime with torsion is only de Sitter along one direction or is unperturbed along one direction and perturbed against the other two. Cartan torsion contributes to the frequency of oscillations in the model. Therefore gravitational waves could be triggered by the spin-torsion scalar density .
Steiner trees for fixed orientation metrics
DEFF Research Database (Denmark)
Brazil, Marcus; Zachariasen, Martin
2009-01-01
We consider the problem of constructing Steiner minimum trees for a metric defined by a polygonal unit circle (corresponding to s = 2 weighted legal orientations in the plane). A linear-time algorithm to enumerate all angle configurations for degree three Steiner points is given. We provide...... a simple proof that the angle configuration for a Steiner point extends to all Steiner points in a full Steiner minimum tree, such that at most six orientations suffice for edges in a full Steiner minimum tree. We show that the concept of canonical forms originally introduced for the uniform orientation...... metric generalises to the fixed orientation metric. Finally, we give an O(s n) time algorithm to compute a Steiner minimum tree for a given full Steiner topology with n terminal leaves....
On 2-dimensional Kaehler metrics with one holomorphic isometry
Chimento, Samuele
2016-01-01
We show how to write any Kaehler metric of complex dimension 2 admitting a holomorphic isometry as a simple 1-real-function deformation of a Gibbons-Hawking metric. Hyper-Kaehler metrics with a tri-holomorphic isometry (Gibbons-Hawking metrics) or with a mono-holomorphic isometry are recovered for particular values of the additional function. The new general metric can be used as an Ansatz in several interesting physical problems.
Boolean metric spaces and Boolean algebraic varieties
Avilés, Antonio
2009-01-01
The concepts of Boolean metric space and convex combination are used to characterize polynomial maps in a class of commutative Von Neumann regular rings including Boolean rings and p-rings, that we have called CFG-rings. In those rings, the study of the category of algebraic varieties (i.e. sets of solutions to a finite number of polynomial equations with polynomial maps as morphisms) is equivalent to the study of a class of Boolean metric spaces, that we call here CFG-spaces.
Geons and the quantum information metric
Sinamuli, Musema; Mann, Robert B.
2017-07-01
We investigate the proposed duality between a quantum information metric in a CFTd +1 and the volume of a maximum time slice in the dual AdSd +2 for topological geons. Examining the specific cases of Banados-Teitelboim-Zannelli (BTZ) black holes and planar Schwarzschild-anti-de Sitter black holes, along with their geon counterparts, we find that the proposed duality relation for geons is the same apart from a factor of 4. The information metric therefore provides a probe of the topology of the bulk spacetime.
Metric-affine gravitation theory and superpotentials
Energy Technology Data Exchange (ETDEWEB)
Giachetta, G.; Mangiarotti, L.; Saltarelli, A. [Camerino, Univ. (Italy). Dipt. di Matematica e Fisica
1997-05-01
They consider a metric-affine theory of gravity in which the dynamical fields are the Lorentzian metrics and the non-symmetric linear connections on the worked manifold X. Working with a Lagrangian density which is invariant under general covariant transformations and using standard tools of the calculus of variations, they study the corresponding currents. They find that the superpotential takes a nice form involving the torsion of the linear connection in a simple way and generalizing the well-known Komar superpotential. A feature of our approach is the use of the Poincare`-Cartan form in relation to the first variational formula of the calculus of variations.
Cohesion Metrics for Ontology Design and Application
Directory of Open Access Journals (Sweden)
Haining Yao
2005-01-01
Full Text Available Recently, domain specific ontology development has been driven by research on the Semantic Web. Ontologies have been suggested for use in many application areas targeted by the Semantic Web, such as dynamic web service composition and general web service matching. Fundamental characteristics of these ontologies must be determined in order to effectively make use of them: for example, Sirin, Hendler and Parsia have suggested that determining fundamental characteristics of ontologies is important for dynamic web service composition. Our research examines cohesion metrics for ontologies. The cohesion metrics examine the fundamental quality of cohesion as it relates to ontologies.
... Craniosynostosis Information Page Creutzfeldt-Jakob Disease Information Page Cushing's Syndrome Information Page Dandy-Walker Syndrome Information Page Deep Brain Stimulation for Parkinson's Disease Information Page Dementia Information ...
... continue Prenatal Diagnosis Pregnant women can have their unborn babies tested for the HEXA deficit that causes ... child may have seizures and become completely disabled. Death usually occurs by the time the child is ...
... MF, eds. Creasy and Resnik's Maternal-Fetal Medicine: Principles and Practice . 7th ed. Philadelphia, PA: Elsevier Saunders; 2014:chap 30. Review Date 10/30/2016 Updated by: Anna C. Edens Hurst, MD, MS, Assistant Professor in Medical Genetics, The University of Alabama at Birmingham, Birmingham, AL. ...
Business model metrics: an open repository
Heikkila, M.; Bouwman, W.A.G.A.; Heikkila, J.; Solaimani, S.; Janssen, W.
2015-01-01
Development of successful business models has become a necessity in turbulent business environments, but compared to research on business modeling tools, attention to the role of metrics in designing business models in literature is limited. Building on existing approaches to business models and
Vehicle Integrated Prognostic Reasoner (VIPR) Metric Report
Cornhill, Dennis; Bharadwaj, Raj; Mylaraswamy, Dinkar
2013-01-01
This document outlines a set of metrics for evaluating the diagnostic and prognostic schemes developed for the Vehicle Integrated Prognostic Reasoner (VIPR), a system-level reasoner that encompasses the multiple levels of large, complex systems such as those for aircraft and spacecraft. VIPR health managers are organized hierarchically and operate together to derive diagnostic and prognostic inferences from symptoms and conditions reported by a set of diagnostic and prognostic monitors. For layered reasoners such as VIPR, the overall performance cannot be evaluated by metrics solely directed toward timely detection and accuracy of estimation of the faults in individual components. Among other factors, overall vehicle reasoner performance is governed by the effectiveness of the communication schemes between monitors and reasoners in the architecture, and the ability to propagate and fuse relevant information to make accurate, consistent, and timely predictions at different levels of the reasoner hierarchy. We outline an extended set of diagnostic and prognostics metrics that can be broadly categorized as evaluation measures for diagnostic coverage, prognostic coverage, accuracy of inferences, latency in making inferences, computational cost, and sensitivity to different fault and degradation conditions. We report metrics from Monte Carlo experiments using two variations of an aircraft reference model that supported both flat and hierarchical reasoning.
Rainbow metric formalism and Relative Locality
Loret, Niccoló
2015-01-01
This proceeding is based on a talk prepared for the XIII Marcell Grossmann meeting. We summarise some results of work in progress in collaboration with Giovanni Amelino-Camelia about momentum dependent (Rainbow) metrics in a Relative Locality framework and we show that this formalism is equivalent to the Hamiltonian formalization of Relative Locality obtained in arXiv:1102.4637.
Colliding waves in metric-affine gravity
García, A; Macías, A; Mielke, E W; Socorro, J; García, Alberto; Lämmerzahl, Claus; Macías, Alfredo; Mielke, Eckehard W.; Socorro, José
1998-01-01
We generalize the formulation of the colliding gravitational waves to metric-affine theories and present an example of such kind of exact solutions. The plane waves are equipped with five symmetries and the resulting geometry after the collision possesses two spacelike Killing vectors.
Thermodynamical properties of metric fluctuations during inflation
Bellini, M
2001-01-01
I study a thermodynamical approach to scalar metric perturbations during the inflationary stage. In the power-law expanding universe here studied, I find a negative heat capacity as a manifestation of superexponential growing for the number of states in super Hubble scales. The power spectrum depends on the Gibbons-Hawking and Hagedorn temperatures.
Validation metrics for turbulent plasma transport
Holland, C.
2016-06-01
Developing accurate models of plasma dynamics is essential for confident predictive modeling of current and future fusion devices. In modern computer science and engineering, formal verification and validation processes are used to assess model accuracy and establish confidence in the predictive capabilities of a given model. This paper provides an overview of the key guiding principles and best practices for the development of validation metrics, illustrated using examples from investigations of turbulent transport in magnetically confined plasmas. Particular emphasis is given to the importance of uncertainty quantification and its inclusion within the metrics, and the need for utilizing synthetic diagnostics to enable quantitatively meaningful comparisons between simulation and experiment. As a starting point, the structure of commonly used global transport model metrics and their limitations is reviewed. An alternate approach is then presented, which focuses upon comparisons of predicted local fluxes, fluctuations, and equilibrium gradients against observation. The utility of metrics based upon these comparisons is demonstrated by applying them to gyrokinetic predictions of turbulent transport in a variety of discharges performed on the DIII-D tokamak [J. L. Luxon, Nucl. Fusion 42, 614 (2002)], as part of a multi-year transport model validation activity.
Business model metrics: an open repository
Heikkila, M.; Bouwman, W.A.G.A.; Heikkila, J.; Solaimani, S.; Janssen, W.
2015-01-01
Development of successful business models has become a necessity in turbulent business environments, but compared to research on business modeling tools, attention to the role of metrics in designing business models in literature is limited. Building on existing approaches to business models and per
Metric Conversion and the School Shop
Jackman, Arthur A.
1976-01-01
Cost of metric conversion in school shops is examined, and the author categories all the shops in the school and gives useful information on which shops are the easiest to convert, which are most complicated, where resistance is most likely to be met, and where conversion is most urgent. The math department is seen as catalyst. (Editor/HD)
Outsourced Similarity Search on Metric Data Assets
DEFF Research Database (Denmark)
Yiu, Man Lung; Assent, Ira; Jensen, Christian S.
2012-01-01
This paper considers a cloud computing setting in which similarity querying of metric data is outsourced to a service provider. The data is to be revealed only to trusted users, not to the service provider or anyone else. Users query the server for the most similar data objects to a query example...
Calabi–Yau metrics and string compactification
Directory of Open Access Journals (Sweden)
Michael R. Douglas
2015-09-01
Full Text Available Yau proved an existence theorem for Ricci-flat Kähler metrics in the 1970s, but we still have no closed form expressions for them. Nevertheless there are several ways to get approximate expressions, both numerical and analytical. We survey some of this work and explain how it can be used to obtain physical predictions from superstring theory.
Metrical musings on Littlewood and friends
DEFF Research Database (Denmark)
Haynes, A.; Jensen, Jonas Lindstrøm; Kristensen, Simon
We prove a metrical result on a family of conjectures related to the Littlewood conjecture, namely the original Littlewood conjecture, the mixed Littlewood conjecture of de Mathan and Teulié and a hybrid between a conjecture of Cassels and the Littlewood conjecture. It is shown that the set of nu...
Metrical categories in infancy and adulthood.
Hannon, Erin E; Trehub, Sandra E
2005-01-01
Intrinsic perceptual biases for simple duration ratios are thought to constrain the organization of rhythmic patterns in music. We tested that hypothesis by exposing listeners to folk melodies differing in metrical structure (simple or complex duration ratios), then testing them on alterations that preserved or violated the original metrical structure. Simple meters predominate in North American music, but complex meters are common in many other musical cultures. In Experiment 1, North American adults rated structure-violating alterations as less similar to the original version than structure-preserving alterations for simple-meter patterns but not for complex-meter patterns. In Experiment 2, adults of Bulgarian or Macedonian origin provided differential ratings to structure-violating and structure-preserving alterations in complex- as well as simple-meter contexts. In Experiment 3, 6-month-old infants responded differentially to structure-violating and structure-preserving alterations in both metrical contexts. These findings imply that the metrical biases of North American adults reflect enculturation processes rather than processing predispositions for simple meters.
Gravity Dual of Quantum Information Metric
Miyaji, Masamichi; Shiba, Noburo; Takayanagi, Tadashi; Watanabe, Kento
2015-01-01
We study a quantum information metric (or fidelity susceptibility) in conformal field theories with respect to a small perturbation by a primary operator. We argue that its gravity dual is approximately given by a volume of maximal time slice in an AdS spacetime when the perturbation is exactly marginal. We confirm our claim in several examples.
Strong Ideal Convergence in Probabilistic Metric Spaces
Indian Academy of Sciences (India)
Celaleddin Şençimen; Serpil Pehlivan
2009-06-01
In the present paper we introduce the concepts of strongly ideal convergent sequence and strong ideal Cauchy sequence in a probabilistic metric (PM) space endowed with the strong topology, and establish some basic facts. Next, we define the strong ideal limit points and the strong ideal cluster points of a sequence in this space and investigate some properties of these concepts.
Performance Metrics Research Project - Final Report
Energy Technology Data Exchange (ETDEWEB)
Deru, M.; Torcellini, P.
2005-10-01
NREL began work for DOE on this project to standardize the measurement and characterization of building energy performance. NREL's primary research objectives were to determine which performance metrics have greatest value for determining energy performance and to develop standard definitions and methods of measuring and reporting that performance.
On Decomposable Measures Induced by Metrics
Directory of Open Access Journals (Sweden)
Dong Qiu
2012-01-01
Full Text Available We prove that for a given normalized compact metric space it can induce a σ-max-superdecomposable measure, by constructing a Hausdorff pseudometric on its power set. We also prove that the restriction of this set function to the algebra of all measurable sets is a σ-max-decomposable measure. Finally we conclude this paper with two open problems.
Business model metrics: an open repository
Heikkila, M.; Bouwman, W.A.G.A.; Heikkila, J.; Solaimani, S.; Janssen, W.
2015-01-01
Development of successful business models has become a necessity in turbulent business environments, but compared to research on business modeling tools, attention to the role of metrics in designing business models in literature is limited. Building on existing approaches to business models and per
The LSST metrics analysis framework (MAF)
Jones, R. L.; Yoachim, Peter; Chandrasekharan, Srinivasan; Connolly, Andrew J.; Cook, Kem H.; Ivezic, Željko; Krughoff, K. S.; Petry, Catherine; Ridgway, Stephen T.
2014-07-01
We describe the Metrics Analysis Framework (MAF), an open-source python framework developed to provide a user-friendly, customizable, easily-extensible set of tools for analyzing data sets. MAF is part of the Large Synoptic Survey Telescope (LSST) Simulations effort. Its initial goal is to provide a tool to evaluate LSST Operations Simulation (OpSim) simulated surveys to help understand the effects of telescope scheduling on survey performance, however MAF can be applied to a much wider range of datasets. The building blocks of the framework are Metrics (algorithms to analyze a given quantity of data), Slicers (subdividing the overall data set into smaller data slices as relevant for each Metric), and Database classes (to access the dataset and read data into memory). We describe how these building blocks work together, and provide an example of using MAF to evaluate different dithering strategies. We also outline how users can write their own custom Metrics and use these within the framework.
A new universal colour image fidelity metric
Toet, A.; Lucassen, M.P.
2003-01-01
We extend a recently introduced universal grayscale image quality index to a newly developed perceptually decorrelated colour space. The resulting colour image fidelity metric quantifies the distortion of a processed colour image relative to its original version. We evaluated the new colour image fi
Assessing Software Quality Through Visualised Cohesion Metrics
Directory of Open Access Journals (Sweden)
Timothy Shih
2001-05-01
Full Text Available Cohesion is one of the most important factors for software quality as well as maintainability, reliability and reusability. Module cohesion is defined as a quality attribute that seeks for measuring the singleness of the purpose of a module. The module of poor quality can be a serious obstacle to the system quality. In order to design a good software quality, software managers and engineers need to introduce cohesion metrics to measure and produce desirable software. A highly cohesion software is thought to be a desirable constructing. In this paper, we propose a function-oriented cohesion metrics based on the analysis of live variables, live span and the visualization of processing element dependency graph. We give six typical cohesion examples to be measured as our experiments and justification. Therefore, a well-defined, well-normalized, well-visualized and well-experimented cohesion metrics is proposed to indicate and thus enhance software cohesion strength. Furthermore, this cohesion metrics can be easily incorporated with software CASE tool to help software engineers to improve software quality.
Validation metrics for turbulent plasma transport
Energy Technology Data Exchange (ETDEWEB)
Holland, C., E-mail: chholland@ucsd.edu [Center for Energy Research, University of California, San Diego, La Jolla, California 92093-0417 (United States)
2016-06-15
Developing accurate models of plasma dynamics is essential for confident predictive modeling of current and future fusion devices. In modern computer science and engineering, formal verification and validation processes are used to assess model accuracy and establish confidence in the predictive capabilities of a given model. This paper provides an overview of the key guiding principles and best practices for the development of validation metrics, illustrated using examples from investigations of turbulent transport in magnetically confined plasmas. Particular emphasis is given to the importance of uncertainty quantification and its inclusion within the metrics, and the need for utilizing synthetic diagnostics to enable quantitatively meaningful comparisons between simulation and experiment. As a starting point, the structure of commonly used global transport model metrics and their limitations is reviewed. An alternate approach is then presented, which focuses upon comparisons of predicted local fluxes, fluctuations, and equilibrium gradients against observation. The utility of metrics based upon these comparisons is demonstrated by applying them to gyrokinetic predictions of turbulent transport in a variety of discharges performed on the DIII-D tokamak [J. L. Luxon, Nucl. Fusion 42, 614 (2002)], as part of a multi-year transport model validation activity.
On A Schwarszchild-Like Metric
Anastasiei, Mihai; Gottlieb, Ioan
2012-12-01
In this short Note we would like to bring into the attention of people working in General Relativity a Schwarzschild like metric found by Professor Cleopatra Mociuţchi in sixties. It was obtained by the A. Sommerfeld reasoning from his treatise "Elektrodynamik" but using instead of the energy conserving law from the classical Physics, the relativistic energy conserving law.
DIGITAL MARKETING: SUCCESS METRICS, FUTURE TRENDS
Preeti Kaushik
2017-01-01
Abstract – Business Marketing is one of the prospective which has been tremendously affected by digital world in last few years. Digital marketing refers to doing advertising through digital channels. This paper provides detailed study of metrics to measure success of digital marketing platform and glimpse of future of technologies by 2020.
Clean Cities 2011 Annual Metrics Report
Energy Technology Data Exchange (ETDEWEB)
Johnson, C.
2012-12-01
This report details the petroleum savings and vehicle emissions reductions achieved by the U.S. Department of Energy's Clean Cities program in 2011. The report also details other performance metrics, including the number of stakeholders in Clean Cities coalitions, outreach activities by coalitions and national laboratories, and alternative fuel vehicles deployed.
Clean Cities 2010 Annual Metrics Report
Energy Technology Data Exchange (ETDEWEB)
Johnson, C.
2012-10-01
This report details the petroleum savings and vehicle emissions reductions achieved by the U.S. Department of Energy's Clean Cities program in 2010. The report also details other performance metrics, including the number of stakeholders in Clean Cities coalitions, outreach activities by coalitions and national laboratories, and alternative fuel vehicles deployed.
Nonunital Spectral Triples Associated to Degenerate Metrics
Rennie, A.
We show that one can define (p,∞)-summable spectral triples using degenerate metrics on smooth manifolds. Furthermore, these triples satisfy Connes-Moscovici's discrete and finite dimension spectrum hypothesis, allowing one to use the Local Index Theorem [1] to compute the pairing with K-theory. We demonstrate this with a concrete example.
Calabi-Yau metrics and string compactification
Douglas, Michael R
2015-01-01
Yau proved an existence theorem for Ricci-flat K\\"ahler metrics in the 1970's, but we still have no closed form expressions for them. Nevertheless there are several ways to get approximate expressions, both numerical and analytical. We survey some of this work and explain how it can be used to obtain physical predictions from superstring theory.
Calabi-Yau metrics and string compactification
Douglas, Michael R.
2015-09-01
Yau proved an existence theorem for Ricci-flat Kähler metrics in the 1970s, but we still have no closed form expressions for them. Nevertheless there are several ways to get approximate expressions, both numerical and analytical. We survey some of this work and explain how it can be used to obtain physical predictions from superstring theory.
Montalvo, Anna Lisa E; Filocamo, Mirella; Vlahovicek, Kristian; Dardis, Andrea; Lualdi, Susanna; Corsolini, Fabio; Bembi, Bruno; Pittis, Maria Gabriela
2005-09-01
Tay-Sachs disease (TSD) is a recessively inherited disorder caused by the hexosaminidase A deficiency. We report the molecular characterization performed on 31 Italian patients, 22 with the infantile, acute form of TSD and nine patients with the subacute juvenile form, biochemically classified as B1 Variant. Of the 29 different alleles identified, fourteen were due to 15 novel mutations, two being in-cis on a new complex allele. The new alleles caused four frameshifts, three premature stop codons, three amino acid changes, two amino acid deletions and two splicing alterations. As previously reported, the c.533G>A (p.R178H) mutation was present either in homozygosity or as compound heterozygote, in all the patients with the late onset TSD form (B1 Variant); the allele frequency in this group is discussed by comparison with that found in infantile TSD.
Rahman, Syed Faisal ur
2016-01-01
In this study, we are going to discuss the accelerated expansion of the universe and how this accelerated expansion affects the paths of photons from cosmic microwave background radiation (CMB). Then we will see how wide-field galaxy surveys along with cosmic CMB anisotropy maps can help us in studying dark energy. The cross-correlation of galaxy over/under-density maps with CMB anisotropy maps help us in measuring one of the most useful signatures of dark energy i.e. Integrated Sachs-Wolfe (ISW) effect. ISW effect explains the blue-shifting and red-shifting of CMB photons when they reach to us after passing through large scale structures and super-voids respectively. We will look into the theoretical foundations behind ISW effect and discuss how modern all sky galaxy surveys like EMU-ASKAP will be useful in studying the effect.
Saunders, Marnie M; Schwentker, Edwards P; Kay, David B; Bennett, Gordon; Jacobs, Christopher R; Verstraete, Mary C; Njus, Glen O
2003-02-01
In this study, we developed an approach for prosthetic foot design incorporating motion analysis, mechanical testing and computer analysis. Using computer modeling and finite element analysis, a three-dimensional (3D), numerical foot model of the solid ankle cushioned heel (SACH) foot was constructed and analyzed based upon loading conditions obtained from the gait analysis of an amputee and validated experimentally using mechanical testing. The model was then used to address effects of viscoelastic heel performance numerically. This is just one example of the type of parametric analysis and design enabled by this approach. More importantly, by incorporating the unique gait characteristics of the amputee, these parametric analyses may lead to prosthetic feet more appropriately representing a particular user's needs, comfort and activity level.
Cohen-Tannoudji, M; Marchand, P; Akli, S; Sheardown, S A; Puech, J P; Kress, C; Gressens, P; Nassogne, M C; Beccari, T; Muggleton-Harris, A L
1995-12-01
Tay-Sachs disease is an autosomal recessive lysosomal storage disease caused by beta-hexosaminidase A deficiency and leads to death in early childhood. The disease results from mutations in the HEXA gene, which codes for the alpha chain of beta-hexosaminidase. The castastrophic neurodegenerative progression of the disease is thought to be a consequence of massive neuronal accumulation of GM2 ganglioside and related glycolipids in the brain and nervous system of the patients. Fuller understanding of the pathogenesis and the development of therapeutic procedures have both suffered from the lack of an animal model. We have used gene targeting in embryonic stem (ES) cells to disrupt the mouse Hexa gene. Mice homozygous for the disrupted allele mimic several biochemical and histological features of human Tay-Sachs disease. Hexa-/- mice displayed a total deficiency of beta-hexosaminidase A activity, and membranous cytoplasmic inclusions typical of GM2 gangliosidoses were found in the cytoplasm of their neurons. However, while the number of storage neurons increased with age, it remained low compared with that found in human, and no apparent motor or behavioral disorders could be observed. This suggests that the presence of beta-hexosaminidase A is not an absolute requirement of ganglioside degradation in mice. These mice should help us to understand several aspects of the disease as well as the physiological functions of hexosaminidase in mice. They should also provide a valuable animal model in which to test new forms of therapy, and in particular gene delivery into the central nervous system.
Gort, Laura; de Olano, Natalia; Macías-Vidal, Judit; Coll, M A Josep
2012-09-10
The GM2 gangliosidoses are autosomal recessive lysosomal storage diseases caused by a deficiency of the β-hexosaminidase A enzyme. This enzyme is composed of two polypeptide chains designated the α- and β- subunits and it interacts with the GM2 activator protein. The HEXA and HEXB genes encode the α-subunit and the β-subunit, respectively. Mutations in these genes are causative of Tay-Sachs disease (HEXA) and Sandhoff disease (HEXB). We analyzed the complete HEXA gene in 34 Spanish patients with Tay-Sachs disease and the HEXB gene in 14 Spanish patients with Sandhoff disease. We identified 27 different mutations, 14 of which were novel, in the HEXA gene and 14 different mutations, 8 of which unreported until now, in the HEXB gene, and we attempted to correlate these mutations with the clinical presentation of the patients. We found a high frequency of c.459+5G>A (IVS4+5G>A) mutation in HEXA affected patients, 22 of 68 alleles, which represent the 32.4%. This is the highest percentage found of this mutation in a population. All patients homozygous for mutation c.459+5G>A presented with the infantile form of the disease and, as previously reported, patients carrying mutation p.R178H in at least one of the alleles presented with a milder form. In HEXB affected patients, the novel deletion c.171delG accounts for 21.4% of the mutant alleles (6/28). All patients with this deletion showed the infantile form of the disease. The Spanish GM2 gangliosidoses affected patients show a great mutational heterogeneity as seen in other inherited lisosomal diseases in this country. Copyright © 2012. Published by Elsevier B.V.
Merolla, Giovanni; Paladini, Paolo; Di Napoli, Giuseppe; Campi, Fabrizio; Porcellini, Giuseppe
2015-02-01
Hill-Sachs lesions are compression fractures that result from shoulder dislocation. They involve "engaging" the humeral head on the anterior glenoid rim when the arm is abducted and externally rotated. The defect grows as the number of dislocations increases. Arthroscopic remplissage and anterior Bankart repair do not significantly affect infraspinatus strength while ensuring healing of the capsulotenodesis. Cohort study; Level of evidence, 3. Sixty-one patients with traumatic anterior shoulder instability treated by arthroscopic Bankart repair and Hill-Sachs remplissage at least 24 months previously were compared with a control group of 40 healthy participants. Preoperative imaging included magnetic resonance imaging for Bankart lesion identification and computed tomography to quantify the humeral head defect. Active range of motion and clinical scores (Walch-Duplay, Constant-Murley, and Rowe) were assessed. External rotation (ER) and internal rotation (IR) were measured with arm at the side (ER1 and IR1) and abducted at 90° (ER2 and IR2). Infraspinatus strength was assessed with the scapula free (infraspinatus strength test [IST]) and retracted (infraspinatus scapula retraction test [ISRT]). Infraspinatus tenodesis and posterior capsulodesis healing were evaluated by ultrasound (US). The follow-up median was 39.5 months (range, 24-56 months). One patient experienced a recurrence of instability at 34 months. In the remplissage patients, ER1 was significantly lower in the affected compared with the unaffected shoulder (P lesions. The ER and IR restriction does not significantly affect quality of life. Infraspinatus strength recovery is satisfactory even compared with healthy subjects. Ultrasound examination allows accurate evaluation of capsulotenodesis healing. © 2014 The Author(s).
A Novel Performance Metric for Building an Optimized Classifier
Directory of Open Access Journals (Sweden)
Mohammad Hossin
2011-01-01
Full Text Available Problem statement: Typically, the accuracy metric is often applied for optimizing the heuristic or stochastic classification models. However, the use of accuracy metric might lead the searching process to the sub-optimal solutions due to its less discriminating values and it is also not robust to the changes of class distribution. Approach: To solve these detrimental effects, we propose a novel performance metric which combines the beneficial properties of accuracy metric with the extended recall and precision metrics. We call this new performance metric as Optimized Accuracy with Recall-Precision (OARP. Results: In this study, we demonstrate that the OARP metric is theoretically better than the accuracy metric using four generated examples. We also demonstrate empirically that a naïve stochastic classification algorithm, which is Monte Carlo Sampling (MCS algorithm trained with the OARP metric, is able to obtain better predictive results than the one trained with the conventional accuracy metric. Additionally, the t-test analysis also shows a clear advantage of the MCS model trained with the OARP metric over the accuracy metric alone for all binary data sets. Conclusion: The experiments have proved that the OARP metric leads stochastic classifiers such as the MCS towards a better training model, which in turn will improve the predictive results of any heuristic or stochastic classification models.
How to evaluate objective video quality metrics reliably
DEFF Research Database (Denmark)
Korhonen, Jari; Burini, Nino; You, Junyong
2012-01-01
The typical procedure for evaluating the performance of different objective quality metrics and indices involves comparisons between subjective quality ratings and the quality indices obtained using the objective metrics in question on the known video sequences. Several correlation indicators can...
Regular black hole metrics and the weak energy condition
Energy Technology Data Exchange (ETDEWEB)
Balart, Leonardo, E-mail: leonardo.balart@ufrontera.cl [I.C.B. – Institut Carnot de Bourgogne, UMR 5209, CNRS, Faculté des Sciences Mirande, Université de Bourgogne, 9 Avenue Alain Savary, BP 47870, 21078 Dijon Cedex (France); Departamento de Ciencias Físicas, Facultad de Ingeniería y Ciencias, Universidad de La Frontera, Casilla 54-D, Temuco (Chile); Vagenas, Elias C., E-mail: elias.vagenas@ku.edu.kw [Theoretical Physics Group, Department of Physics, Kuwait University, P.O. Box 5969, Safat 13060 (Kuwait)
2014-03-07
In this work we construct a family of spherically symmetric, static, charged regular black hole metrics in the context of Einstein-nonlinear electrodynamics theory. The construction of the charged regular black hole metrics is based on three requirements: (a) the weak energy condition should be satisfied, (b) the energy–momentum tensor should have the symmetry T{sub 0}{sup 0}=T{sub 1}{sup 1}, and (c) these metrics have to asymptotically behave as the Reissner–Nordström black hole metric. In addition, these charged regular black hole metrics depend on two parameters which for specific values yield regular black hole metrics that already exist in the literature. Furthermore, by relaxing the third requirement, we construct more general regular black hole metrics which do not behave asymptotically as a Reissner–Nordström black hole metric.
Structural Properties of Hard Metric TSP Inputs
Mömke, Tobias
The metric traveling salesman problem is one of the most prominent APX-complete optimization problems. An important particularity of this problem is that there is a large gap between the known upper bound and lower bound on the approximability (assuming P ≠ NP). In fact, despite more than 30 years of research, no one could find a better approximation algorithm than the 1.5-approximation provided by Christofides. The situation is similar for a related problem, the metric Hamiltonian path problem, where the start and the end of the path are prespecified: the best approximation ratio up to date is 5/3 by an algorithm presented by Hoogeveen almost 20 years ago.
Metric-Aware Secure Service Orchestration
Directory of Open Access Journals (Sweden)
Gabriele Costa
2012-12-01
Full Text Available Secure orchestration is an important concern in the internet of service. Next to providing the required functionality the composite services must also provide a reasonable level of security in order to protect sensitive data. Thus, the orchestrator has a need to check whether the complex service is able to satisfy certain properties. Some properties are expressed with metrics for precise definition of requirements. Thus, the problem is to analyse the values of metrics for a complex business process. In this paper we extend our previous work on analysis of secure orchestration with quantifiable properties. We show how to define, verify and enforce quantitative security requirements in one framework with other security properties. The proposed approach should help to select the most suitable service architecture and guarantee fulfilment of the declared security requirements.
Machine Learning for ATLAS DDM Network Metrics
Lassnig, Mario; The ATLAS collaboration; Vamosi, Ralf
2016-01-01
The increasing volume of physics data is posing a critical challenge to the ATLAS experiment. In anticipation of high luminosity physics, automation of everyday data management tasks has become necessary. Previously many of these tasks required human decision-making and operation. Recent advances in hardware and software have made it possible to entrust more complicated duties to automated systems using models trained by machine learning algorithms. In this contribution we show results from our ongoing automation efforts. First, we describe our framework for distributed data management and network metrics, automatically extract and aggregate data, train models with various machine learning algorithms, and eventually score the resulting models and parameters. Second, we use these models to forecast metrics relevant for network-aware job scheduling and data brokering. We show the characteristics of the data and evaluate the forecasting accuracy of our models.
Metric for Early Measurement of Software Complexity
Directory of Open Access Journals (Sweden)
Ghazal Keshavarz,
2011-06-01
Full Text Available Software quality depends on several factors such as on time delivery; within budget and fulfilling user's needs. Complexity is one of the most important factors that may affect the quality. Therefore, measuring and controlling the complexity result in improving the quality. So far, most of the researches have tried to identify and measure the complexity in design and code phase. However, whenwe have the code or design for software, it is too late to control complexity. In this article, with emphasis on Requirement Engineering process, we analyze the causes of software complexity, particularly in the first phase of software development, and propose a requirement based metric. This metric enables a software engineer to measure the complexity before actual design and implementation and choosestrategies that are appropriate to the software complexity degree, thus saving on cost and human resource wastage and, more importantly, leading to lower maintenance costs.
A Taxonomy of Metrics for Hosted Databases
Directory of Open Access Journals (Sweden)
Jordan Shropshire
2006-04-01
Full Text Available The past three years has seen exponential growth in the number of organizations who have elected to entrust core information technology functions to application service providers. Of particular interest is the outsourcing of critical systems such as corporate databases. Major banks and financial service firms are contracting with third party organizations, sometimes overseas, for their database needs. These sophisticated contracts require careful supervision by both parties. Due to the complexities of web- based applications and the complicated nature of databases, an entire class of software suites has been developed to measure the quality of service the database is providing. This article investigates the performance metrics which have evolved to satisfy this need and describes a taxonomy of performance metrics for hosted databases.
A universal metric for ferroic energy materials.
Brück, Ekkes; Yibole, Hargen; Zhang, Lian
2016-08-13
After almost 20 years of intensive research on magnetocaloric effects near room temperature, magnetic refrigeration with first-order magnetocaloric materials has come close to real-life applications. Many materials have been discussed as potential candidates to be used in multicaloric devices. However, phase transitions in ferroic materials are often hysteretic and a metric is needed to estimate the detrimental effects of this hysteresis. We propose the coefficient of refrigerant performance, which compares the net work in a reversible cycle with the positive work on the refrigerant, as a universal metric for ferroic materials. Here, we concentrate on examples from magnetocaloric materials and only consider one barocaloric experiment. This is mainly due to lack of data on electrocaloric materials. It appears that adjusting the field-induced transitions and the hysteresis effects can minimize the losses in first-order materials.This article is part of the themed issue 'Taking the temperature of phase transitions in cool materials'.
Infinitesimally Lipschitz functions on metric spaces
Durand, E
2009-01-01
For a metric space $X$, we study the space $D^{\\infty}(X)$ of bounded functions on $X$ whose infinitesimal Lipschitz constant is uniformly bounded. $D^{\\infty}(X)$ is compared with the space $\\LIP^{\\infty}(X)$ of bounded Lipschitz functions on $X$, in terms of different properties regarding the geometry of $X$. We also obtain a Banach-Stone theorem in this context. In the case of a metric measure space, we also compare $D^{\\infty}(X)$ with the Newtonian-Sobolev space $N^{1, \\infty}(X)$. In particular, if $X$ supports a doubling measure and satisfies a local Poincar{\\'e} inequality, we obtain that $D^{\\infty}(X)=N^{1, \\infty}(X)$.
Restoring the sting to metric preheating
Bassett, B A; Maartens, R; Kaiser, D I; Bassett, Bruce A.; Gordon, Chris; Maartens, Roy; Kaiser, David I.
2000-01-01
The relative growth of field and metric perturbations during preheating is sensitive to initial conditions set in the preceding inflationary phase. Recent work suggests this may protect super-Hubble metric perturbations from resonant amplification during preheating. We show that this possibility is fragile and extremely sensitive to the specific form of the interactions between the inflaton and other fields. The suppression is naturally absent in two classes of preheating in which either (1) the critical points (hence the vacua) of the effective potential during inflation are deformed away from the origin, or (2) the effective masses of fields during inflation are small but during preheating are large. Unlike the simple toy model of a g^2 \\phi^2 \\chi^2 coupling, most realistic particle physics models contain these other features. Moreover, they generically lead to both adiabatic and isocurvature modes and non-Gaussian scars on super-Hubble scales. Large-scale coherent magnetic fields may also appear naturally...
Derived Metric Tensors for Flow Surface Visualization.
Obermaier, H; Joy, K I
2012-12-01
Integral flow surfaces constitute a widely used flow visualization tool due to their capability to convey important flow information such as fluid transport, mixing, and domain segmentation. Current flow surface rendering techniques limit their expressiveness, however, by focusing virtually exclusively on displacement visualization, visually neglecting the more complex notion of deformation such as shearing and stretching that is central to the field of continuum mechanics. To incorporate this information into the flow surface visualization and analysis process, we derive a metric tensor field that encodes local surface deformations as induced by the velocity gradient of the underlying flow field. We demonstrate how properties of the resulting metric tensor field are capable of enhancing present surface visualization and generation methods and develop novel surface querying, sampling, and visualization techniques. The provided results show how this step towards unifying classic flow visualization and more advanced concepts from continuum mechanics enables more detailed and improved flow analysis.
Metrics and causality on Moyal planes
Franco, Nicolas
2015-01-01
Metrics structures stemming from the Connes distance promote Moyal planes to the status of quantum metric spaces. We discuss this aspect in the light of recent developments, emphasizing the role of Moyal planes as representative examples of a recently introduced notion of quantum (noncommutative) locally compact space. We move then to the framework of Lorentzian noncommutative geometry and we examine the possibility of defining a notion of causality on Moyal plane, which is somewhat controversial in the area of mathematical physics. We show the actual existence of causal relations between the elements of a particular class of pure (coherent) states on Moyal plane with related causal structure similar to the one of the usual Minkowski space, up to the notion of locality.
Enhancing U.S. Coast Guard Metrics
2015-01-01
Enhancing U.S. Coast Guard Metrics Scott Savitz, Henry H. Willis , Aaron C. Davenport, Martina Melliand, William Sasser, Elizabeth Tencza, Dulani...evaluate their utility in other contexts. 6 See Stephanie Young, Henry H. Willis , Melinda Moore, and Jeffrey Engstrom, Measuring Cooperative...front cost of the USS Gerald R. Ford aircraft carrier . U.S. Air Force, “United States Air Force Fiscal Year 2015 Budget Overview,” Washington, D.C
The Planck Vacuum and the Schwarzschild Metrics
Directory of Open Access Journals (Sweden)
Daywitt W. C.
2009-07-01
Full Text Available The Planck vacuum (PV is assumed to be the source of the visible universe. So under conditions of sufficient stress, there must exist a pathway through which energy from the PV can travel into this universe. Conversely, the passage of energy from the visible universe to the PV must also exist under the same stressful conditions. The following examines two versions of the Schwarzschild metric equation for compatability with this open-pathway idea.
Metrics and Its Function in Poetry
Institute of Scientific and Technical Information of China (English)
XIAO Zhong-qiong; CHEN Min-jie
2013-01-01
Poetry is a special combination of musical and linguistic qualities-of sounds both regarded as pure sound and as mean-ingful speech. Part of the pleasure of poetry lies in its relationship with music. Metrics, including rhythm and meter, is an impor-tant method for poetry to express poetic sentiment. Through the introduction of poetic language and typical examples, the writer of this paper tries to discuss the relationship between sound and meaning.
Autonomous Exploration Using an Information Gain Metric
2016-03-01
quantified by computing the entropy of the robot’s a posteriori pose estimate. The robot’s pose history along its trajectory is captured by the mapping...man-portable robot system. The robot was equipped with additional computing hardware to increase the capabilities of the platform. Similarly, the...Laboratory Autonomous Exploration Using an Information Gain Metric by Nicholas C Fung, Jason M Gregory, and John G Rogers Computational and
Asymptotic properties of the C-Metric
Sladek, Pavel
2010-01-01
The aim of this article is to analyze the asymptotic properties of the C-metric, using a general method specified in work of Tafel and coworkers, [1], [2], [3]. By finding an appropriate conformal factor $\\Omega$, it allows the investigation of the asymptotic properties of a given asymptotically flat spacetime. The news function and Bondi mass aspect are computed, their general properties are analyzed, as well as the small mass, small acceleration, small and large Bondi time limits.
Ocean Model Assessment with Lagrangian Metrics
2016-06-07
Ocean Model Assessment With Lagrangian Metrics” Pearn P. Niiler Scripps Institution of Oceanography 9500 Gilman Drive MC 0213 La Jolla, CA...project are to aid in the development of accurate modeling of upper ocean circulation by using data on circulation observations to test models . These tests...or metrics, will be statistical measures of model and data comparisons. It is believed that having accurate models of upper ocean currents will
Teleparallel Gravitational Energy in the Gamma Metric
Salti, M
2006-01-01
The Moller energy(due to matter and fields including gravity) distribution of the gamma metric is studied in tele-parallel gravity. The result is the same as those obtained in general relativity by Virbhadra in the Weinberg complex and Yang-Radincshi in the Moller definition. Our result is also independent of the three teleparallel dimensionless coupling constants, which means that it is valid not only in the teleparallel equivalent of general relativity, but also in any teleparallel model.
Menger curvature and rectifiability in metric spaces
2012-01-01
We show that for any metric space $X$ the condition \\[ \\int_X\\int_X\\int_X c(z_1,z_2,z_3)^2\\, d\\Hm z_1\\, d\\Hm z_2\\, d\\Hm z_3 < \\infty, \\] where $c(z_1,z_2,z_3)$ is the Menger curvature of the triple $(z_1,z_2,z_3)$, guarantees that $X$ is rectifiable.
A Metrics Approach for Collaborative Systems
Directory of Open Access Journals (Sweden)
Cristian CIUREA
2009-01-01
Full Text Available This article presents different types of collaborative systems, their structure and classification. This paper defines the concept of virtual campus as a collaborative system. It builds architecture for virtual campus oriented on collaborative training processes. It analyses the quality characteristics of collaborative systems and propose techniques for metrics construction and validation in order to evaluate them. The article analyzes different ways to increase the efficiency and the performance level in collaborative banking systems.
Anisotropic rectangular metric for polygonal surface remeshing
Pellenard, Bertrand
2013-06-18
We propose a new method for anisotropic polygonal surface remeshing. Our algorithm takes as input a surface triangle mesh. An anisotropic rectangular metric, defined at each triangle facet of the input mesh, is derived from both a user-specified normal-based tolerance error and the requirement to favor rectangle-shaped polygons. Our algorithm uses a greedy optimization procedure that adds, deletes and relocates generators so as to match two criteria related to partitioning and conformity.
Smart Grid Status and Metrics Report
Energy Technology Data Exchange (ETDEWEB)
Balducci, Patrick J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Weimar, Mark R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kirkham, Harold [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
2014-07-01
To convey progress made in achieving the vision of a smart grid, this report uses a set of six characteristics derived from the National Energy Technology Laboratory Modern Grid Strategy. It measures 21 metrics to provide insight into the grid’s capacity to embody these characteristics. This report looks across a spectrum of smart grid concerns to measure the status of smart grid deployment and impacts.
Metric Development for Continuous Process Improvement
2011-03-01
improve the bottom line of an organization. The first step of this process is to solicit the key performance indicators ( KPIs ) that best reflect the...organization’s mission. The second step is to use and/or develop metrics based on those KPIs to measure the organization’s mission performance today...The third step is to capture the trends of those KPIs over time to see if the organization is getting better or worse. The final step is to
What can article-level metrics do for you?
Fenner, Martin
2013-10-01
Article-level metrics (ALMs) provide a wide range of metrics about the uptake of an individual journal article by the scientific community after publication. They include citations, usage statistics, discussions in online comments and social media, social bookmarking, and recommendations. In this essay, we describe why article-level metrics are an important extension of traditional citation-based journal metrics and provide a number of example from ALM data collected for PLOS Biology.
Decomposition-based transfer distance metric learning for image classification.
Luo, Yong; Liu, Tongliang; Tao, Dacheng; Xu, Chao
2014-09-01
Distance metric learning (DML) is a critical factor for image analysis and pattern recognition. To learn a robust distance metric for a target task, we need abundant side information (i.e., the similarity/dissimilarity pairwise constraints over the labeled data), which is usually unavailable in practice due to the high labeling cost. This paper considers the transfer learning setting by exploiting the large quantity of side information from certain related, but different source tasks to help with target metric learning (with only a little side information). The state-of-the-art metric learning algorithms usually fail in this setting because the data distributions of the source task and target task are often quite different. We address this problem by assuming that the target distance metric lies in the space spanned by the eigenvectors of the source metrics (or other randomly generated bases). The target metric is represented as a combination of the base metrics, which are computed using the decomposed components of the source metrics (or simply a set of random bases); we call the proposed method, decomposition-based transfer DML (DTDML). In particular, DTDML learns a sparse combination of the base metrics to construct the target metric by forcing the target metric to be close to an integration of the source metrics. The main advantage of the proposed method compared with existing transfer metric learning approaches is that we directly learn the base metric coefficients instead of the target metric. To this end, far fewer variables need to be learned. We therefore obtain more reliable solutions given the limited side information and the optimization tends to be faster. Experiments on the popular handwritten image (digit, letter) classification and challenge natural image annotation tasks demonstrate the effectiveness of the proposed method.
Ghost free massive gravity with singular reference metrics
Zhang, Hongsheng; Li, Xin-Zhou
2016-06-01
An auxiliary metric (reference metric) is inevitable in massive gravity theory. In the scenario of the gauge/gravity duality, massive gravity with a singular reference metric is used to study momentum dissipation, which describes the electric and heat conductivity for normal conductors. We demonstrate in detail that the de Rham-Gabadadze-Tolley (dRGT) massive gravity with a singular reference metric is ghost free.
The Development and Demonstration of The Metric Assessment Tool
1993-09-01
motivate continuous improvement and likewise quality. Attributen of MNaninafui Metrica Section Overview. The importance of metrics cannot be overstated...some of the attributes of meaningful measures discussed earlier in this chapter. The Metrica Handbook. This guide is utilized by a variety of Air...Metric Assessment Tool. 3-8 Metrica Belaction The metric assessment tool was designed to apply to any type of metric. Two criteria were established for
Semantic maps as metrics on meanings
Directory of Open Access Journals (Sweden)
Michael Cysouw
2010-01-01
Full Text Available By using the world?s linguistic diversity, the study of meaning can be transformed from an introspective inquiry into a subject of empirical investigation. For this to be possible, the notion of meaning has to be operationalized by defining the meaning of an expression as the collection of all contexts in which the expression can be used. Under this definition, meaning can be empirically investigated by sampling contexts. A semantic map is a technique to show the relations between such sampled contextual occurrences. Or, formulated more technically, a semantic map is a visualization of a metric on contexts sampled to represent a domain of meaning. Or, put more succinctly, a semantic map is a metric on meaning. To establish such a metric, a notion of (dissimilarity is needed. The similarity between two meanings can be empirically investigated by looking at their encoding in many different languages. The more similar these encodings, in language after language, the more similar the contexts. So, to investigate the similarity between two contextualized meanings, only judgments about the similarity between expressions within the structure of individual languages are needed. As an example of this approach, data on cross-linguistic variation in inchoative/causative alternations from Haspelmath (1993 is reanalyzed.
An information theoretic approach for privacy metrics
Directory of Open Access Journals (Sweden)
Michele Bezzi
2010-12-01
Full Text Available Organizations often need to release microdata without revealing sensitive information. To this scope, data are anonymized and, to assess the quality of the process, various privacy metrics have been proposed, such as k-anonymity, l-diversity, and t-closeness. These metrics are able to capture different aspects of the disclosure risk, imposing minimal requirements on the association of an individual with the sensitive attributes. If we want to combine them in a optimization problem, we need a common framework able to express all these privacy conditions. Previous studies proposed the notion of mutual information to measure the different kinds of disclosure risks and the utility, but, since mutual information is an average quantity, it is not able to completely express these conditions on single records. We introduce here the notion of one-symbol information (i.e., the contribution to mutual information by a single record that allows to express and compare the disclosure risk metrics. In addition, we obtain a relation between the risk values t and l, which can be used for parameter setting. We also show, by numerical experiments, how l-diversity and t-closeness can be represented in terms of two different, but equally acceptable, conditions on the information gain..
A computational imaging target specific detectivity metric
Preece, Bradley L.; Nehmetallah, George
2017-05-01
Due to the large quantity of low-cost, high-speed computational processing available today, computational imaging (CI) systems are expected to have a major role for next generation multifunctional cameras. The purpose of this work is to quantify the performance of theses CI systems in a standardized manner. Due to the diversity of CI system designs that are available today or proposed in the near future, significant challenges in modeling and calculating a standardized detection signal-to-noise ratio (SNR) to measure the performance of these systems. In this paper, we developed a path forward for a standardized detectivity metric for CI systems. The detectivity metric is designed to evaluate the performance of a CI system searching for a specific known target or signal of interest, and is defined as the optimal linear matched filter SNR, similar to the Hotelling SNR, calculated in computational space with special considerations for standardization. Therefore, the detectivity metric is designed to be flexible, in order to handle various types of CI systems and specific targets, while keeping the complexity and assumptions of the systems to a minimum.
Statistical estimation of ozone exposure metrics
Blankenship, Erin E.; Stefanski, L. A.
Data from recent experiments at North Carolina State University and other locations provide a unique opportunity to study the effect of ambient ozone on the growth of clover. The data consist of hourly ozone measurements over a 140 day growing season at eight sites in the US, coupled with clover growth response data measured every 28 days. The objective is to model an indicator of clover growth as a function of ozone exposure. A common strategy for dealing with the numerous hourly ozone measurements is to reduce these to a single summary measurement, a so-called exposure metric, for the growth period of interest. However, the mean ozone value is not necessarily the best summarization, as it is widely believed that low levels of ozone have a negligible effect on growth, whereas peak ozone values are deleterious to plant growth. There are also suspected interactions with available sunlight, temperature and humidity. A number of exposure metrics have been proposed that reflect these beliefs by assigning different weights to ozone values according to magnitude, time of day, temperature and humidity. These weighting schemes generally depend on parameters that have, to date, been subjectively determined. We propose a statistical approach based on profile likelihoods to estimate the parameters in these exposure metrics.
Stability of extremal metrics under complex deformations
Rollin, Yann; Tipler, Carl
2011-01-01
Let $(\\mathcal {X},\\Omega)$ be a closed polarized complex manifold, $g$ be an extremal metric on $\\mathcal X$ that represents the K\\"ahler class $\\Omega$, and $G$ be a compact connected subgroup of the isometry group $Isom(\\mathcal{X},g)$. Assume that the Futaki invariant relative to $G$ is nondegenerate at $g$. Consider a smooth family $(\\mathcal{M}\\to B)$ of polarized complex deformations of $(\\mathcal{X},\\Omega)\\simeq (\\mathcal{M}_0,\\Theta_0)$ provided with a holomorphic action of $G$. Then for every $t\\in B$ sufficiently small, there exists an $h^{1,1}(\\cX)$-dimensional family of extremal K\\"ahler metrics on $\\mathcal{M}_t$ whose K\\"ahler classes are arbitrarily close to $\\Theta_t$. We apply this deformation theory to analyze the Mukai-Umemura 3-fold and its complex deformations. In particular, we prove that there are certain complex deformation of the Mukai-Umemura 3-folds which have extremal metric of non constant scalar curvature with Kaehler class $c_1$.
Metric-torsion preheating: cosmic dynamo mechanism?
de Andrade, L C Garcia
2014-01-01
Earlier Bassett et al [Phys Rev D 63 (2001) 023506] investigated the amplification of large scale magnetic fields during preheating and inflation in several different models. They argued that in the presence of conductivity resonance effect is weakened. From a dynamo equation in spacetimes endowed with torsion recently derived by Garcia de Andrade [Phys Lett B 711: 143 (2012)] it is shown that a in a universe with pure torsion in Minkowski spacetime the cosmological magnetic field is enhanced by ohmic or non-conductivity effect, which shows that the metric-torsion effects is worth while of being studied. In this paper we investigated the metric-torsion preheating perturbation, which leads to the seed cosmological magnetic field in the universe with torsion is of the order of $B_{seed}\\sim{10^{-37}Gauss}$ which is several orders of magnitude weaker than the decoupling value obtained from pure metric preheating of $10^{-15}Gauss$. Despite of the weakness of the magnetic field this seed field may seed the galact...
Multi-Armed Bandits in Metric Spaces
Kleinberg, Robert; Upfal, Eli
2008-01-01
In a multi-armed bandit problem, an online algorithm chooses from a set of strategies in a sequence of trials so as to maximize the total payoff of the chosen strategies. While the performance of bandit algorithms with a small finite strategy set is quite well understood, bandit problems with large strategy sets are still a topic of very active investigation, motivated by practical applications such as online auctions and web advertisement. The goal of such research is to identify broad and natural classes of strategy sets and payoff functions which enable the design of efficient solutions. In this work we study a very general setting for the multi-armed bandit problem in which the strategies form a metric space, and the payoff function satisfies a Lipschitz condition with respect to the metric. We refer to this problem as the "Lipschitz MAB problem". We present a complete solution for the multi-armed problem in this setting. That is, for every metric space (L,X) we define an isometry invariant which bounds f...
Security Metrics: A Solution in Search of a Problem
Rosenblatt, Joel
2008-01-01
Computer security is one of the most complicated and challenging fields in technology today. A security metrics program provides a major benefit: looking at the metrics on a regular basis offers early clues to changes in attack patterns or environmental factors that may require changes in security strategy. The term "security metrics" loosely…
FIXED POINT RESULTS ON METRIC-TYPE SPACES
Institute of Scientific and Technical Information of China (English)
Monica COSENTINO; Peyman SALIMI; Pasquale VETRO
2014-01-01
In this paper we obtain fixed point and common fixed point theorems for self-mappings defined on a metric-type space, an ordered metric-type space or a normal cone metric space. Moreover, some examples and an application to integral equations are given to illustrate the usability of the obtained results.
Geodesics in the space of K\\"ahler cone metrics
Calama, Simone
2012-01-01
In this paper, we prove the existence and uniqueness of the weak cone geodesics in the space of K\\"ahler cone metrics by solving the singular, homogeneous complex Monge-Amp\\`{e}re equation. As an application, we prove the metric space structure of the appropriate subspace of the space of K\\"ahler cone metrics.
Meter Detection in Symbolic Music Using Inner Metric Analysis
de Haas, W.B.|info:eu-repo/dai/nl/304841250; Volk, A.|info:eu-repo/dai/nl/304842117
2016-01-01
In this paper we present PRIMA: a new model tailored to symbolic music that detects the meter and the first downbeat position of a piece. Given onset data, the metrical structure of a piece is interpreted using the Inner Metric Analysis (IMA) model. IMA identifies the strong and weak metrical
Graev metrics on free products and HNN extensions
DEFF Research Database (Denmark)
Slutsky, Konstantin
2014-01-01
We give a construction of two-sided invariant metrics on free products (possibly with amalgamation) of groups with two-sided invariant metrics and, under certain conditions, on HNN extensions of such groups. Our approach is similar to the Graev's construction of metrics on free groups over pointed...
Tide or Tsunami? The Impact of Metrics on Scholarly Research
Bonnell, Andrew G.
2016-01-01
Australian universities are increasingly resorting to the use of journal metrics such as impact factors and ranking lists in appraisal and promotion processes, and are starting to set quantitative "performance expectations" which make use of such journal-based metrics. The widespread use and misuse of research metrics is leading to…
22 CFR 226.15 - Metric system of measurement.
2010-04-01
... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Metric system of measurement. 226.15 Section....S. NON-GOVERNMENTAL ORGANIZATIONS Pre-award Requirements § 226.15 Metric system of measurement. (a...) declares that the metric system is the preferred measurement system for U.S. trade and commerce....