Electric-hexadecapole (24-pole) Coulomb integrals
NASA Astrophysics Data System (ADS)
Chidichimo, Marita C.; Stastna, Marek
1996-03-01
We obtain the quantal zero-energy-loss limit of the radial integrals arising in the nonrelativistic atomic excitation of electric-hexadecapole transitions. We compare these results to the classical limit and the WKB approximation. We show the different behavior of the Coulomb integrals in the WKB approximation in the cases of repulsive and attractive potentials as functions of the Sommerfeld number η.
Convergence of Feynman integrals in Coulomb gauge QCD
Andraši, A.; Taylor, J.C.
2014-12-15
At 2-loop order, Feynman integrals in the Coulomb gauge are divergent over the internal energy variables. Nevertheless, it is known how to calculate the effective action, provided that the external gluon fields are all transverse. We show that, for the two-gluon Greens function as an example, the method can be extended to include longitudinal external fields. The longitudinal Greens functions appear in the BRST identities. As an intermediate step, we use a flow gauge, which interpolates between the Feynman and Coulomb gauges.
The equation-transform model for Dirac–Morse problem including Coulomb tensor interaction
Ortakaya, Sami
2013-11-15
The approximate solutions of Dirac equation with Morse potential in the presence of Coulomb-like tensor potential are obtained by using Laplace transform (LT) approach. The energy eigenvalue equation of the Dirac particles is found and some numerical results are obtained. By using convolution integral, the corresponding radial wave functions are presented in terms of confluent hypergeometric functions. -- Highlights: •The Dirac equation with tensor interaction is solved by using Laplace transform. •For solving this equation, we introduce the equation-transform model. •Numerical results and plots for pseudospin and spin symmetric solutions are given. •The obtained numerical results by using transform method are compared with orthogonal polynomial method.
Laplace Transforms without Integration
ERIC Educational Resources Information Center
Robertson, Robert L.
2017-01-01
Calculating Laplace transforms from the definition often requires tedious integrations. This paper provides an integration-free technique for calculating Laplace transforms of many familiar functions. It also shows how the technique can be applied to probability theory.
On Dirac-Coulomb problem in (2+1) dimensional space-time and path integral quantization
Haouat, S.; Chetouani, L.
2012-06-15
The problem of Dirac particle interacting with Coulomb potential in (2+1) dimensions is formulated in the framework of super-symmetric path integrals where the spin degrees of freedom are described by odd Grassmannian variables. The relative propagator is expressed through Cartesian coordinates in a Hamiltonian form by the use of an adequate transformation. The passage to the polar coordinates permitted us to calculate the fixed energy Green's function and to extract bound states and associating wave functions.
NASA Astrophysics Data System (ADS)
Przybytek, Michal; Helgaker, Trygve
2013-08-01
We analyze the accuracy of the Coulomb energy calculated using the Gaussian-and-finite-element-Coulomb (GFC) method. In this approach, the electrostatic potential associated with the molecular electronic density is obtained by solving the Poisson equation and then used to calculate matrix elements of the Coulomb operator. The molecular electrostatic potential is expanded in a mixed Gaussian-finite-element (GF) basis set consisting of Gaussian functions of s symmetry centered on the nuclei (with exponents obtained from a full optimization of the atomic potentials generated by the atomic densities from symmetry-averaged restricted open-shell Hartree-Fock theory) and shape functions defined on uniform finite elements. The quality of the GF basis is controlled by means of a small set of parameters; for a given width of the finite elements d, the highest accuracy is achieved at smallest computational cost when tricubic (n = 3) elements are used in combination with two (γH = 2) and eight (γ1st = 8) Gaussians on hydrogen and first-row atoms, respectively, with exponents greater than a given threshold (α _min^G=0.5). The error in the calculated Coulomb energy divided by the number of atoms in the system depends on the system type but is independent of the system size or the orbital basis set, vanishing approximately like d4 with decreasing d. If the boundary conditions for the Poisson equation are calculated in an approximate way, the GFC method may lose its variational character when the finite elements are too small; with larger elements, it is less sensitive to inaccuracies in the boundary values. As it is possible to obtain accurate boundary conditions in linear time, the overall scaling of the GFC method for large systems is governed by another computational step—namely, the generation of the three-center overlap integrals with three Gaussian orbitals. The most unfavorable (nearly quadratic) scaling is observed for compact, truly three-dimensional systems
Przybytek, Michal; Helgaker, Trygve
2013-08-07
We analyze the accuracy of the Coulomb energy calculated using the Gaussian-and-finite-element-Coulomb (GFC) method. In this approach, the electrostatic potential associated with the molecular electronic density is obtained by solving the Poisson equation and then used to calculate matrix elements of the Coulomb operator. The molecular electrostatic potential is expanded in a mixed Gaussian-finite-element (GF) basis set consisting of Gaussian functions of s symmetry centered on the nuclei (with exponents obtained from a full optimization of the atomic potentials generated by the atomic densities from symmetry-averaged restricted open-shell Hartree-Fock theory) and shape functions defined on uniform finite elements. The quality of the GF basis is controlled by means of a small set of parameters; for a given width of the finite elements d, the highest accuracy is achieved at smallest computational cost when tricubic (n = 3) elements are used in combination with two (γ(H) = 2) and eight (γ(1st) = 8) Gaussians on hydrogen and first-row atoms, respectively, with exponents greater than a given threshold (αmin (G)=0.5). The error in the calculated Coulomb energy divided by the number of atoms in the system depends on the system type but is independent of the system size or the orbital basis set, vanishing approximately like d(4) with decreasing d. If the boundary conditions for the Poisson equation are calculated in an approximate way, the GFC method may lose its variational character when the finite elements are too small; with larger elements, it is less sensitive to inaccuracies in the boundary values. As it is possible to obtain accurate boundary conditions in linear time, the overall scaling of the GFC method for large systems is governed by another computational step-namely, the generation of the three-center overlap integrals with three Gaussian orbitals. The most unfavorable (nearly quadratic) scaling is observed for compact, truly three-dimensional systems
Efficient evaluation of three-center Coulomb integrals
NASA Astrophysics Data System (ADS)
Samu, Gyula; Kállay, Mihály
2017-05-01
In this study we pursue the most efficient paths for the evaluation of three-center electron repulsion integrals (ERIs) over solid harmonic Gaussian functions of various angular momenta. First, the adaptation of the well-established techniques developed for four-center ERIs, such as the Obara-Saika, McMurchie-Davidson, Gill-Head-Gordon-Pople, and Rys quadrature schemes, and the combinations thereof for three-center ERIs is discussed. Several algorithmic aspects, such as the order of the various operations and primitive loops as well as prescreening strategies, are analyzed. Second, the number of floating point operations (FLOPs) is estimated for the various algorithms derived, and based on these results the most promising ones are selected. We report the efficient implementation of the latter algorithms invoking automated programming techniques and also evaluate their practical performance. We conclude that the simplified Obara-Saika scheme of Ahlrichs is the most cost-effective one in the majority of cases, but the modified Gill-Head-Gordon-Pople and Rys algorithms proposed herein are preferred for particular shell triplets. Our numerical experiments also show that even though the solid harmonic transformation and the horizontal recurrence require significantly fewer FLOPs if performed at the contracted level, this approach does not improve the efficiency in practical cases. Instead, it is more advantageous to carry out these operations at the primitive level, which allows for more efficient integral prescreening and memory layout.
Low rank factorization of the Coulomb integrals for periodic coupled cluster theory
NASA Astrophysics Data System (ADS)
Hummel, Felix; Tsatsoulis, Theodoros; Grüneis, Andreas
2017-03-01
We study a tensor hypercontraction decomposition of the Coulomb integrals of periodic systems where the integrals are factorized into a contraction of six matrices of which only two are distinct. We find that the Coulomb integrals can be well approximated in this form already with small matrices compared to the number of real space grid points. The cost of computing the matrices scales as O (N4) using a regularized form of the alternating least squares algorithm. The studied factorization of the Coulomb integrals can be exploited to reduce the scaling of the computational cost of expensive tensor contractions appearing in the amplitude equations of coupled cluster methods with respect to system size. We apply the developed methodologies to calculate the adsorption energy of a single water molecule on a hexagonal boron nitride monolayer in a plane wave basis set and periodic boundary conditions.
Coulomb Stress Distribution Along the Fairweather and Queen Charlotte Transform Fault System
NASA Astrophysics Data System (ADS)
Bufe, C. G.
2004-12-01
Tectonic loading and Coulomb stress transfer are modeled along the right-lateral Fairweather and Queen Charlotte transform fault system using a three-dimensional boundary element program. The loading model includes slip below 12 km along the transform as well as motion of the Pacific plate and is consistent with most available GPS displacement rate data. Coulomb stress transfer from adjacent fault segments is shown to be a weak contributing factor to the failure of the southeastern (Sitka) segment of the Fairweather fault (M 7.6, 1972), advancing the clock by only about 8 months. Failure resulted from a combination of loading from below (99 percent) by slip of nearly 5 cm/yr since before1900, and of stress transfer (1 percent) from major earthquakes on adjoining segments of the Queen Charlotte fault to the southeast (M 8.1 in 1949) and the Fairweather fault to the northwest (M 7.8 on Lituya segment in 1958). Combined Coulomb stress increases exceeded 4 MPa at a depth of 8 km prior to the Sitka earthquake. Coulomb stress transferred from the nearby M 9.2 Alaska earthquake of 1964 also may have advanced the clock for the 1972 event, but only by a month or two. Minimum recurrence times, based on average co-seismic displacements estimated from seismic moments and fault dimensions, range from about 80 years for the 1958 and 1972 events to 160 years for the 1949 earthquake. This implies stresses of 5 to 10 MPa at 8 km depth at failure, assuming total stress drops. Continued tectonic loading over the last half century and stress transfer from the M 7.6 Sitka event has resulted in re-stressing the adjacent segments by about 3 MPa at 8 km depth, as evidenced by the occurrence of a M 6.8 earthquake on the northwestern part of the Queen Charlotte fault on June 28, 2004, the largest since 1949. The segment of the Queen Charlotte fault immediately southeast of the 1949 rupture has accumulated about 6 MPa at 8 km through loading since 1900 and stress transfer in 1949. A
Closed-form expressions for the Dirac-Coulomb radial rt integrals
NASA Astrophysics Data System (ADS)
Bessis, N.; Bessis, G.; Roux, D.
1985-10-01
A novel procedure is devised in order to obtain closed-form expressions of the Dirac-Coulomb radial rt integrals in terms of the Dirac energy ɛ=\\{1+Z2α2/[v+(k2-Z2 α2)1/2]2\\}-1/2, where v=n-||k||, and of the Dirac quantum number k=(-1)j+l+1/2(j+(1/2)). In this procedure, well adapted for symbolic computation, the fundamental array of the rt radial integrals is obtained from the rt-1 array.
Guseinov, Israfil; Mamedov, Bahtiyar; Rzaeva, Afet
2002-04-01
The recurrence relations are established for the basic one-center Coulomb integrals over Slater-type orbitals (STOs). These formulae and the recurrence relations for basic overlap integrals are utilized for the calculation of multicenter electron-repulsion integrals. The calculations of multicenter electron-repulsion integrals are performed by the use of translation formulae for STOs obtained from the Lambda and Coulomb Sturmian exponential-type functions (ETFs). It is shown that these integrals show a faster convergence rate in the case of Coulomb Sturmian ETFs. The accuracy of the results is quite high for the quantum numbers of STOs and for the arbitrary values of internuclear distances and screening constants of atomic orbitals.
Off-shell Jost solutions for Coulomb and Coulomb-like interactions in all partial waves
Laha, U.; Bhoi, J.
2013-01-15
By exploiting the theory of ordinary differential equations, with judicious use of boundary conditions, interacting Green's functions and their integral transforms together with certain properties of higher transcendental functions, useful analytical expressions for the off-shell Jost solutions for motion in Coulomb and Coulomb-nuclear potentials are derived in maximal reduced form through different approaches to the problem in the representation space. The exact analytical expressions for the off-shell Jost solutions for Coulomb and Coulomb-like potentials are believed to be useful for the description of the charged particle scattering/reaction processes.
NASA Astrophysics Data System (ADS)
Hestand, Nicholas J.; Spano, Frank C.
2015-12-01
The spectroscopic differences between J and H-aggregates are traditionally attributed to the spatial dependence of the Coulombic coupling, as originally proposed by Kasha. However, in tightly packed molecular aggregates wave functions on neighboring molecules overlap, leading to an additional charge transfer (CT) mediated exciton coupling with a vastly different spatial dependence. The latter is governed by the nodal patterns of the molecular LUMOs and HOMOs from which the electron (te) and hole (th) transfer integrals derive. The sign of the CT-mediated coupling depends on the sign of the product teth and is therefore highly sensitive to small (sub-Angstrom) transverse displacements or slips. Given that Coulombic and CT-mediated couplings exist simultaneously in tightly packed molecular systems, the interference between the two must be considered when defining J and H-aggregates. Generally, such π-stacked aggregates do not abide by the traditional classification scheme of Kasha: for example, even when the Coulomb coupling is strong the presence of a similarly strong but destructively interfering CT-mediated coupling results in "null-aggregates" which spectroscopically resemble uncoupled molecules. Based on a Frenkel/CT Holstein Hamiltonian that takes into account both sources of electronic coupling as well as intramolecular vibrations, vibronic spectral signatures are developed for integrated Frenkel/CT systems in both the perturbative and resonance regimes. In the perturbative regime, the sign of the lowest exciton band curvature, which rigorously defines J and H-aggregation, is directly tracked by the ratio of the first two vibronic peak intensities. Even in the resonance regime, the vibronic ratio remains a useful tool to evaluate the J or H nature of the system. The theory developed is applied to the reversible H to J-aggregate transformations recently observed in several perylene bisimide systems.
Hestand, Nicholas J.; Spano, Frank C.
2015-12-28
The spectroscopic differences between J and H-aggregates are traditionally attributed to the spatial dependence of the Coulombic coupling, as originally proposed by Kasha. However, in tightly packed molecular aggregates wave functions on neighboring molecules overlap, leading to an additional charge transfer (CT) mediated exciton coupling with a vastly different spatial dependence. The latter is governed by the nodal patterns of the molecular LUMOs and HOMOs from which the electron (t{sub e}) and hole (t{sub h}) transfer integrals derive. The sign of the CT-mediated coupling depends on the sign of the product t{sub e}t{sub h} and is therefore highly sensitive to small (sub-Angstrom) transverse displacements or slips. Given that Coulombic and CT-mediated couplings exist simultaneously in tightly packed molecular systems, the interference between the two must be considered when defining J and H-aggregates. Generally, such π-stacked aggregates do not abide by the traditional classification scheme of Kasha: for example, even when the Coulomb coupling is strong the presence of a similarly strong but destructively interfering CT-mediated coupling results in “null-aggregates” which spectroscopically resemble uncoupled molecules. Based on a Frenkel/CT Holstein Hamiltonian that takes into account both sources of electronic coupling as well as intramolecular vibrations, vibronic spectral signatures are developed for integrated Frenkel/CT systems in both the perturbative and resonance regimes. In the perturbative regime, the sign of the lowest exciton band curvature, which rigorously defines J and H-aggregation, is directly tracked by the ratio of the first two vibronic peak intensities. Even in the resonance regime, the vibronic ratio remains a useful tool to evaluate the J or H nature of the system. The theory developed is applied to the reversible H to J-aggregate transformations recently observed in several perylene bisimide systems.
NASA Astrophysics Data System (ADS)
Geipel, Norbert J. M.; Heβ, Bernd A.
1997-07-01
The Douglas-Kroll transformed Dirac-Coulomb Hamiltonian is used to described scalar-relativistic effects in solids. A Hartree-Fock approximation with periodic boundary conditions makes it feasible to use methods originally developed for atoms and molecules to solve the corresponding equations for crystalline systems. The implementation is realized within the CRYSTAL program. Scalar-relativistic effects in silver compounds of FCC structure such as AgF, AgCl, AgBr and Ag are investigated for the molar formation energy, the lattice parameter, the isothermal bulk modulus and the pressure derivative.
Integral transformations applied to image encryption
NASA Astrophysics Data System (ADS)
Vilardy, Juan M.; Perez, Ronal; Torres, Cesar O.
2017-01-01
In this paper we consider the application of the integral transformations for image encryption through optical systems, a mathematical algorithm under Matlab platform using fractional Fourier transform (FrFT) and Random Phase Mask (RPM) for digital images encryption is implemented. The FrFT can be related to others integral transforms, such as: Fourier transform, Sine and Cosine transforms, Radial Hilbert transform, fractional Sine transform, fractional Cosine transform, fractional Hartley transform, fractional Wavelet transform and Gyrator transform, among other transforms. The encryption scheme is based on the use of the FrFT, the joint transform correlator and two RPMs, which provide security and robustness to the implemented security system. One of the RPMs used during encryption-decryption and the fractional order of the FrFT are the keys to improve security and make the system more resistant against security attacks.
Higher-order time integration of Coulomb collisions in a plasma using Langevin equations
Dimits, A. M.; Cohen, B. I.; Caflisch, R. E.; ...
2013-02-08
The extension of Langevin-equation Monte-Carlo algorithms for Coulomb collisions from the conventional Euler-Maruyama time integration to the next higher order of accuracy, the Milstein scheme, has been developed, implemented, and tested. This extension proceeds via a formulation of the angular scattering directly as stochastic differential equations in the two fixed-frame spherical-coordinate velocity variables. Results from the numerical implementation show the expected improvement [O(Δt) vs. O(Δt1/2)] in the strong convergence rate both for the speed |v| and angular components of the scattering. An important result is that this improved convergence is achieved for the angular component of the scattering if andmore » only if the “area-integral” terms in the Milstein scheme are included. The resulting Milstein scheme is of value as a step towards algorithms with both improved accuracy and efficiency. These include both algorithms with improved convergence in the averages (weak convergence) and multi-time-level schemes. The latter have been shown to give a greatly reduced cost for a given overall error level when compared with conventional Monte-Carlo schemes, and their performance is improved considerably when the Milstein algorithm is used for the underlying time advance versus the Euler-Maruyama algorithm. A new method for sampling the area integrals is given which is a simplification of an earlier direct method and which retains high accuracy. Lastly, this method, while being useful in its own right because of its relative simplicity, is also expected to considerably reduce the computational requirements for the direct conditional sampling of the area integrals that is needed for adaptive strong integration.« less
Higher-order time integration of Coulomb collisions in a plasma using Langevin equations
Dimits, A. M.; Cohen, B. I.; Caflisch, R. E.; Rosin, M. S.; Ricketson, L. F.
2013-02-08
The extension of Langevin-equation Monte-Carlo algorithms for Coulomb collisions from the conventional Euler-Maruyama time integration to the next higher order of accuracy, the Milstein scheme, has been developed, implemented, and tested. This extension proceeds via a formulation of the angular scattering directly as stochastic differential equations in the two fixed-frame spherical-coordinate velocity variables. Results from the numerical implementation show the expected improvement [O(Δt) vs. O(Δt^{1/2})] in the strong convergence rate both for the speed |v| and angular components of the scattering. An important result is that this improved convergence is achieved for the angular component of the scattering if and only if the “area-integral” terms in the Milstein scheme are included. The resulting Milstein scheme is of value as a step towards algorithms with both improved accuracy and efficiency. These include both algorithms with improved convergence in the averages (weak convergence) and multi-time-level schemes. The latter have been shown to give a greatly reduced cost for a given overall error level when compared with conventional Monte-Carlo schemes, and their performance is improved considerably when the Milstein algorithm is used for the underlying time advance versus the Euler-Maruyama algorithm. A new method for sampling the area integrals is given which is a simplification of an earlier direct method and which retains high accuracy. Lastly, this method, while being useful in its own right because of its relative simplicity, is also expected to considerably reduce the computational requirements for the direct conditional sampling of the area integrals that is needed for adaptive strong integration.
NASA Technical Reports Server (NTRS)
Straton, Jack C.
1989-01-01
The four-dimensional Fourier-Feynman transformations previously used in analytically reducing the general class of integrals containing multicenter products of 1s hydrogenic orbitals, Coulomb or Yukawa potentials, and plane waves, are replaced by the one-dimensional Gaussian transformation. This reduces the previously required double-diagonalization of the quadratic form of the multicenter integrals to only one diagonalization, yielding a simpler reduced form of the integral. The present work also extends the result to include all s states and pairs of states with l not equal to zero summed over the m quantum number.
Analytic form for the nonrelativistic Coulomb propagator
NASA Astrophysics Data System (ADS)
Blinder, S. M.
1991-01-01
An analytic form for the nonrelativistic Coulomb propagator is derived, thus resolving a long-standing problem in Feynman's path-integral formulation of quantum mechanics. Hostler's formula for the Coulomb Green's function is expanded according to the theorem of Mittag-Leffler, then Fourier transformed term by term to give the Coulomb propagator. The result is a discrete summation over the principal quantum number n, involving Whittaker, Laguerre, Hermite, and error functions. As is the case for other nonquadratic potentials, the Coulomb propagator does not have the canonical structure K=F exp(iS/ħ). Part of the expansion resembles a form derived by Crandall [J. Phys. A 16, 3005 (1983)] for the case of reflectionless potentials.
Transformational Leadership, Integrity, and Power
ERIC Educational Resources Information Center
Harrison, Laura M.
2011-01-01
Transformational leadership enjoys widespread appeal among student affairs professionals. National Association of Student Personnel Administrators (NASPA) and American College Personnel Association (ACPA) conferences frequently feature speakers who promote transformational leadership's two primary tenets: (1) change is the central purpose of…
Transformational Leadership, Integrity, and Power
ERIC Educational Resources Information Center
Harrison, Laura M.
2011-01-01
Transformational leadership enjoys widespread appeal among student affairs professionals. National Association of Student Personnel Administrators (NASPA) and American College Personnel Association (ACPA) conferences frequently feature speakers who promote transformational leadership's two primary tenets: (1) change is the central purpose of…
Reconstruction from cone integral transforms
NASA Astrophysics Data System (ADS)
Palamodov, Victor
2017-10-01
The paper contains new reconstruction formulas for a function on 3D space from data of its cone integrals with fixed opening and integrable weight. In the case of cone integrals with the (non integrable) weight modelling photometric law, a reconstruction is obtained for the non redundant data of cones with the apex running on a curve.
NASA Astrophysics Data System (ADS)
Hollman, David S.; Schaefer, Henry F.; Valeev, Edward F.
2015-04-01
A new estimator for three-center two-particle Coulomb integrals is presented. Our estimator is exact for some classes of integrals and is much more efficient than the standard Schwartz counterpart due to the proper account of distance decay. Although it is not a rigorous upper bound, the maximum degree of underestimation can be controlled by two adjustable parameters. We also give numerical evidence of the excellent tightness of the estimator. The use of the estimator will lead to increased efficiency in reduced-scaling one- and many-body electronic structure theories.
Hollman, David S.; Schaefer, Henry F.; Valeev, Edward F.
2015-04-21
A new estimator for three-center two-particle Coulomb integrals is presented. Our estimator is exact for some classes of integrals and is much more efficient than the standard Schwartz counterpart due to the proper account of distance decay. Although it is not a rigorous upper bound, the maximum degree of underestimation can be controlled by two adjustable parameters. We also give numerical evidence of the excellent tightness of the estimator. The use of the estimator will lead to increased efficiency in reduced-scaling one- and many-body electronic structure theories.
Science education, integral inquiry, transformation and possibility
NASA Astrophysics Data System (ADS)
Stack, Sue
2013-09-01
This paper is written in response to Nancy Davis's article Integral Methodological Pluralism in Science Education Research: Valuing Multiple Perspectives. I use Integral Theory as a framing for this response to explore how it might offer different perspectives and ways of inquiring into Nancy's paper. This process highlights the notion of integral inquiry as a potential for personal transformation. I give an autobiographical account of my own experience in utilising Integral Theory as part of my PhD and its impact on my own becoming. For another perspective I interview Nancy to draw out deeper shared meanings.
A practical integral equation for the structure and thermodynamics of hard sphere Coulomb fluids.
Zwanikken, Jos W; Jha, Prateek K; Olvera de la Cruz, Monica
2011-08-14
A closure for the Ornstein-Zernike equation is presented, applicable for fluids of charged, hard spheres. From an exact, but intractable closure, we derive the radial distribution function of nonlinearized Debye-Hückel theory by subsequent approximations, and use the information to formulate a new closure by an extension of the mean spherical approximation. The radial distribution functions of the new closure, coined Debye-Hückel-extended mean spherical approximation, are in excellent agreement with those resulting from the hyper-netted chain approximation and molecular dynamics simulations, in the regime where the latter are applicable, except for moderately dilute systems at low temperatures where the structure agrees at most qualitatively. The method is numerically more efficient, and more important, convergent in the entire temperature-density plane. We demonstrate that the method is accurate under many conditions for the determination of the structural and thermodynamic properties of homogeneous, symmetric hard-sphere Coulomb systems, and estimate it to be a valuable basis for the formulation of density functional theories for inhomogeneous or highly asymmetric systems.
NASA Astrophysics Data System (ADS)
Skarbek, Rob; Ikari, Matt; Hüpers, Andre; Rempel, Alan; Wilson, Dean; Kitajima, Hiroko
2014-05-01
In accretionary wedges, the mechanical and hydrologic properties along splay faults and the plate boundary fault at the base of the wedge are intimately related to properties within the wedge itself, as well as to sedimentation and/or mass wasting at the wedge surface, and accretionary flux at the wedge toe; Coulomb wedge theories tie these processes together and have been successful in their application to convergent margins. Most such theories assume for the sake of simplicity that mechanical parameters (e.g. bulk density, compressibility, frictional strength) and pore pressure are constant throughout the overlying wedge. However, the values of these parameters must necessarily change with depth and distance from the trench. Here, we derive a model for a fully general Coulomb wedge, parameterized using data specific to the Kumano transect at Nankai, to better understand the location of the basal plate interface and the properties of material composing an actively accretionary prism. We use shear strength data collected for incoming sediments at Integrated Ocean Drilling Program Site C0011 of the NanTroSEIZE project to parameterize the wedge's coefficient of friction. Preliminary results of models where the friction coefficient of the wedge decreases with depth, with other parameters constant and zero cohesion, indicate that including depth dependent frictional strength in the wedge decreases the taper angle of the wedge, with the effect becoming more pronounced with distance from the trench. This model will be further refined by including seismically and numerically determined spatial variations in fluid pressure within the wedge, as well as detailed locations of the upper and basal wedge surfaces along the Kumano transect determined from 3-D seismic data.
ERIC Educational Resources Information Center
Fay, Temple H.
2012-01-01
Viscous damping is commonly discussed in beginning differential equations and physics texts but dry friction or Coulomb friction is not despite dry friction being encountered in many physical applications. One reason for avoiding this topic is that the equations involve a jump discontinuity in the damping term. In this article, we adopt an energy…
ERIC Educational Resources Information Center
Fay, Temple H.
2012-01-01
Viscous damping is commonly discussed in beginning differential equations and physics texts but dry friction or Coulomb friction is not despite dry friction being encountered in many physical applications. One reason for avoiding this topic is that the equations involve a jump discontinuity in the damping term. In this article, we adopt an energy…
Guseinov, Israfil I; Sahin, Ercan
2011-04-01
By the use of ellipsoidal coordinates, the two-center Coulomb and hybrid integrals over complete orthonormal sets of Ψα-ETO exponential type orbitals arising in ab initio calculations of molecules are evaluated, where α = 1,0, -1, -2, ...,. These integrals are expressed through the auxiliary functions Q(ns)(q) and G(-ns)(q). The comparison is made with some values of integrals for Slater type orbitals the computation results of which are in good agreement with those obtained in the literature. The relationships obtained are valid for the arbitrary quantum numbers, screening constants and location of orbitals. Closed form expressions for two-center Coulomb and hybrid integrals for 1s and 2s orbitals with α = 1 are also presented. As an example of application, the Hartree-Fock-Roothaan calculations for the ground state of H(2) molecule are carried out with α = 1 and α = 0.
Bardhan, J. P.; Mathematics and Computer Science
2008-10-14
The importance of molecular electrostatic interactions in aqueous solution has motivated extensive research into physical models and numerical methods for their estimation. The computational costs associated with simulations that include many explicit water molecules have driven the development of implicit-solvent models, with generalized-Born (GB) models among the most popular of these. In this paper, we analyze a boundary-integral equation interpretation for the Coulomb-field approximation (CFA), which plays a central role in most GB models. This interpretation offers new insights into the nature of the CFA, which traditionally has been assessed using only a single point charge in the solute. The boundary-integral interpretation of the CFA allows the use of multiple point charges, or even continuous charge distributions, leading naturally to methods that eliminate the interpolation inaccuracies associated with the Still equation. This approach, which we call boundary-integral-based electrostatic estimation by the CFA (BIBEE/CFA), is most accurate when the molecular charge distribution generates a smooth normal displacement field at the solute-solvent boundary, and CFA-based GB methods perform similarly. Conversely, both methods are least accurate for charge distributions that give rise to rapidly varying or highly localized normal displacement fields. Supporting this analysis are comparisons of the reaction-potential matrices calculated using GB methods and boundary-element-method (BEM) simulations. An approximation similar to BIBEE/CFA exhibits complementary behavior, with superior accuracy for charge distributions that generate rapidly varying normal fields and poorer accuracy for distributions that produce smooth fields. This approximation, BIBEE by preconditioning (BIBEE/P), essentially generates initial guesses for preconditioned Krylov-subspace iterative BEMs. Thus, iterative refinement of the BIBEE/P results recovers the BEM solution; excellent agreement
NASA Astrophysics Data System (ADS)
Bardhan, Jaydeep P.
2008-10-01
The importance of molecular electrostatic interactions in aqueous solution has motivated extensive research into physical models and numerical methods for their estimation. The computational costs associated with simulations that include many explicit water molecules have driven the development of implicit-solvent models, with generalized-Born (GB) models among the most popular of these. In this paper, we analyze a boundary-integral equation interpretation for the Coulomb-field approximation (CFA), which plays a central role in most GB models. This interpretation offers new insights into the nature of the CFA, which traditionally has been assessed using only a single point charge in the solute. The boundary-integral interpretation of the CFA allows the use of multiple point charges, or even continuous charge distributions, leading naturally to methods that eliminate the interpolation inaccuracies associated with the Still equation. This approach, which we call boundary-integral-based electrostatic estimation by the CFA (BIBEE/CFA), is most accurate when the molecular charge distribution generates a smooth normal displacement field at the solute-solvent boundary, and CFA-based GB methods perform similarly. Conversely, both methods are least accurate for charge distributions that give rise to rapidly varying or highly localized normal displacement fields. Supporting this analysis are comparisons of the reaction-potential matrices calculated using GB methods and boundary-element-method (BEM) simulations. An approximation similar to BIBEE/CFA exhibits complementary behavior, with superior accuracy for charge distributions that generate rapidly varying normal fields and poorer accuracy for distributions that produce smooth fields. This approximation, BIBEE by preconditioning (BIBEE/P), essentially generates initial guesses for preconditioned Krylov-subspace iterative BEMs. Thus, iterative refinement of the BIBEE/P results recovers the BEM solution; excellent agreement
Radon transforms and Gegenbauer-Chebyshev integrals, II; examples
NASA Astrophysics Data System (ADS)
Rubin, Boris
2016-08-01
We transfer the results of Part I related to the modified support theorem and the kernel description of the hyperplane Radon transform to totally geodesic transforms on the sphere and the hyperbolic space, the spherical slice transform, and the spherical mean transform for spheres through the origin. The assumptions for functions are formulated in integral terms and close to minimal.
Data integration using color space transforms
Feuquay, Jay W.
1987-01-01
The demand for increased spatial resolution without sacrificing spectral discrimination can be fulfilled by integration of data from different sensor systems and satellite programs. Data of high spatial resolution are frequently available in panchromatic (black-and-white) form rather than multispectral. Techniques gave been developed to combine the higher resolution panchromatic data with a multispectral data set of lower spatial resolution. The standard method of integration modulates the intensity of the mutispectral with the panchromatic data. A less subjective approach uses an algorithm that describes color in terms of intensity (I), hue (H), and saturation (S). Combinations of high resolution panchromatic data (SPOT panchromatic) and lower resolution multispectral data [Landsat thematic mapper (TM), SPOT XS] have been developed. The SPOT data were acquired on April 3, 1986, and the Landsat TM data were acquired on April 5, 1986. The data sets were registered to each other and the multi-spectral data sets were contrast enhanced. The enhanced multispectral data sets were then transformed from red/green/blue (RGB) color space into IHS space. In each case (TM/SPOT panchromatic and SPOT XS/SPOT panchromatic), the SPOT panchromatic data were remapped on a cumulative histogram percentage basis to match the multispectral "I" data. These remapped SPOT panchromatic data were substituted for the original multispectral "I" and the hybrid IHS data transformed back into RGB space for display. While this technique is experimental and still being refined, the results, to date, indicate that the IHS method will be valuable for generating improved images that effectively present both high resolution spatial digital data and multispectral data.
Allied health: integral to transforming health.
Lizarondo, Lucylynn; Turnbull, Catherine; Kroon, Tracey; Grimmer, Karen; Bell, Alison; Kumar, Saravana; McEvoy, Maureen; Milanese, Steve; Russell, Mary; Sheppard, Lorraine; Walters, Julie; Wiles, Louise
2016-04-01
Objective South Australia is taking an innovative step in transforming the way its healthcare is organised and delivered to better manage current and future demands on the health system. In an environment of transforming health services, there are clear opportunities for allied health to assist in determining solutions to various healthcare challenges. A recent opinion piece proposed 10 clinician-driven strategies to assist in maximising value and sustainability of healthcare in Australia. The present study aimed to seek the perspectives of allied health clinicians, educators, researchers, policy makers and managers on these strategies and their relevance to allied health. Methods A survey of allied health practitioners was undertaken to capture their perspectives on the 10 clinician-driven strategies for maximising value and sustainability of healthcare in Australia. Survey findings were then layered with evidence from the literature. Results Highly relevant across allied health are the strategies of discontinuation of low value practices, targeting clinical interventions to those getting greatest benefit, active involvement of patients in shared decision making and self-management and advocating for integrated systems of care. Conclusions Allied health professionals have been involved in the South Australian healthcare system for a prolonged period, but their services are poorly recognised, often overlooked and not greatly supported in existing traditional practices. The results of the present study highlight ways in which healthcare services can implement strategies not only to improve the quality of patient outcomes, but also to offer innovative solutions for future, sustainable healthcare. The findings call for concerted efforts to increase the utilisation of allied health services to ensure the 'maximum value for spend' of the increasingly scarce health dollar. What is known about the topic? In medicine, clinician-driven strategies have been proposed to
Convolution theorems: partitioning the space of integral transforms
NASA Astrophysics Data System (ADS)
Lindsey, Alan R.; Suter, Bruce W.
1999-03-01
Investigating a number of different integral transforms uncovers distinct patterns in the type of translation convolution theorems afforded by each. It is shown that transforms based on separable kernels (aka Fourier, Laplace and their relatives) have a form of the convolution theorem providing for a transform domain product of the convolved functions. However, transforms based on kernels not separable in the function and transform variables mandate a convolution theorem of a different type; namely in the transform domain the convolution becomes another convolution--one function with the transform of the other.
Soft-core potentials in thermodynamic integration: comparing one- and two-step transformations.
Steinbrecher, Thomas; Joung, InSuk; Case, David A
2011-11-30
Molecular dynamics-based free energy calculations allow the determination of a variety of thermodynamic quantities from computer simulations of small molecules. Thermodynamic integration (TI) calculations can suffer from instabilities during the creation or annihilation of particles. This "singularity" problem can be addressed with "soft-core" potential functions which keep pairwise interaction energies finite for all configurations and provide smooth free energy curves. "One-step" transformations, in which electrostatic and van der Waals forces are simultaneously modified, can be simpler and less expensive than "two-step" transformations in which these properties are changed in separate calculations. Here, we study solvation free energies for molecules of different hydrophobicity using both models. We provide recommended values for the two parameters α(LJ) and β(C) controlling the behavior of the soft-core Lennard-Jones and Coulomb potentials and compare one- and two-step transformations with regard to their suitability for numerical integration. For many types of transformations, the one-step procedure offers a convenient and accurate approach to free energy estimates.
New inversion methods for the Lorentz Integral Transform
NASA Astrophysics Data System (ADS)
Andreasi, D.; Leidemann, W.; Reiß, C.; Schwamb, M.
2005-06-01
The Lorentz Integral Transform approach allows microscopic calculations of electromagnetic reaction cross-sections without explicit knowledge of final-state wave functions. The necessary inversion of the transform has to be treated with great care, since it constitutes a so-called ill-posed problem. In this work new inversion techniques for the Lorentz Integral Transform are introduced. It is shown that they all contain a regularization scheme, which is necessary to overcome the ill-posed problem. In addition, it is illustrated that the new techniques have a much broader range of application than the present standard inversion method of the Lorentz Integral Transform.
Radon transforms and Gegenbauer-Chebyshev integrals, I
NASA Astrophysics Data System (ADS)
Rubin, Boris
2017-06-01
We suggest new modifications of the Helgason's support theorem and description of the kernel for the hyperplane Radon transform and its dual. The assumptions for functions are formulated in integral terms and close to minimal. The proofs rely on the properties of the Gegenbauer-Chebyshev integrals which generalize Abel type fractional integrals on the positive half-line.
Fast Fourier transform based direct integration algorithm for the linear canonical transform
NASA Astrophysics Data System (ADS)
Wang, Dayong; Liu, Changgeng; Wang, Yunxin; Zhao, Jie
2011-03-01
The linear canonical transform(LCT) is a parameterized linear integral transform, which is the general case of many well-known transforms such as the Fourier transform(FT), the fractional Fourier transform(FRT) and the Fresnel transform(FST). These integral transforms are of great importance in wave propagation problems because they are the solutions of the wave equation under a variety of circumstances. In optics, the LCT can be used to model paraxial free space propagation and other quadratic phase systems such as lens and graded-index media. A number of algorithms have been presented to fast compute the LCT. When they are used to compute the LCT, the sampling period in the transform domain is dependent on that in the signal domain. This drawback limits their applicability in some cases such as color digital holography. In this paper, a Fast-Fourier-Transform-based Direct Integration algorithm(FFT-DI) for the LCT is presented. The FFT-DI is a fast computational method of the Direct Integration(DI) for the LCT. It removes the dependency of the sampling period in the transform domain on that in the signal domain. Simulations and experimental results are presented to validate this idea.
Fast Fourier transform based direct integration algorithm for the linear canonical transform
NASA Astrophysics Data System (ADS)
Wang, Dayong; Liu, Changgeng; Wang, Yunxin; Zhao, Jie
2010-07-01
The linear canonical transform(LCT) is a parameterized linear integral transform, which is the general case of many well-known transforms such as the Fourier transform(FT), the fractional Fourier transform(FRT) and the Fresnel transform(FST). These integral transforms are of great importance in wave propagation problems because they are the solutions of the wave equation under a variety of circumstances. In optics, the LCT can be used to model paraxial free space propagation and other quadratic phase systems such as lens and graded-index media. A number of algorithms have been presented to fast compute the LCT. When they are used to compute the LCT, the sampling period in the transform domain is dependent on that in the signal domain. This drawback limits their applicability in some cases such as color digital holography. In this paper, a Fast-Fourier-Transform-based Direct Integration algorithm(FFT-DI) for the LCT is presented. The FFT-DI is a fast computational method of the Direct Integration(DI) for the LCT. It removes the dependency of the sampling period in the transform domain on that in the signal domain. Simulations and experimental results are presented to validate this idea.
Exact Green's function of the Aharonov-Bohm-Coulomb system via the Feynman-Kac formula
NASA Astrophysics Data System (ADS)
Chuu, Der-San; Lin, De-Hone
1999-10-01
The Green's function of the relativistic Aharonov-Bohm-Coulomb system is given by the Feynman-Kac formula. The earlier treatment is based on the multiple-valued transformation of Levi-Civitá. The method used in this contribution involves only the explicit form of a simple Green's function and an explicit path integral is avoided.
Science Education, Integral Inquiry, Transformation and Possibility
ERIC Educational Resources Information Center
Stack, Sue
2013-01-01
This paper is written in response to Nancy Davis's article "Integral Methodological Pluralism in Science Education Research: Valuing Multiple Perspectives." I use Integral Theory as a framing for this response to explore how it might offer different perspectives and ways of inquiring into Nancy's paper. This process highlights…
Science Education, Integral Inquiry, Transformation and Possibility
ERIC Educational Resources Information Center
Stack, Sue
2013-01-01
This paper is written in response to Nancy Davis's article "Integral Methodological Pluralism in Science Education Research: Valuing Multiple Perspectives." I use Integral Theory as a framing for this response to explore how it might offer different perspectives and ways of inquiring into Nancy's paper. This process highlights…
Resilience thinking: integrating resilience, adaptability and transformability
Carl Folke; Stephen R. Carpenter; Brian Walker; Marten Scheffer; Terry Chapin; Johan. Rockstrom
2010-01-01
Resilience thinking addresses the dynamics and development of complex social-ecological systems (SES). Three aspects are central: resilience, adaptability and transformability. These aspects interrelate across multiple scales. Resilience in this context is the capacity of a SES to continually change and adapt yet remain within critical thresholds. Adaptability is part...
Improved digital filters for evaluating Fourier and Hankel transform integrals
Anderson, Walter L.
1975-01-01
New algorithms are described for evaluating Fourier (cosine, sine) and Hankel (J0,J1) transform integrals by means of digital filters. The filters have been designed with extended lengths so that a variable convolution operation can be applied to a large class of integral transforms having the same system transfer function. A f' lagged-convolution method is also presented to significantly decrease the computation time when computing a series of like-transforms over a parameter set spaced the same as the filters. Accuracy of the new filters is comparable to Gaussian integration, provided moderate parameter ranges and well-behaved kernel functions are used. A collection of Fortran IV subprograms is included for both real and complex functions for each filter type. The algorithms have been successfully used in geophysical applications containing a wide variety of integral transforms
A Transformative Approach to Work Integrated Learning in Legal Education
ERIC Educational Resources Information Center
Babacan, Alperhan; Babacan, Hurriyet
2015-01-01
Purpose: The purpose of this paper is to discuss the current context, scope and problems in the provision of work-integrated learning (WIL) in legal education and how the adoption transformative pedagogies in WIL which is offered in legal education can foster personal and social transformation in addition to enhancing lawyering skills. The paper…
A Transformative Approach to Work Integrated Learning in Legal Education
ERIC Educational Resources Information Center
Babacan, Alperhan; Babacan, Hurriyet
2015-01-01
Purpose: The purpose of this paper is to discuss the current context, scope and problems in the provision of work-integrated learning (WIL) in legal education and how the adoption transformative pedagogies in WIL which is offered in legal education can foster personal and social transformation in addition to enhancing lawyering skills. The paper…
Integral Transform Methods: A Critical Review of Various Kernels
NASA Astrophysics Data System (ADS)
Orlandini, Giuseppina; Turro, Francesco
2017-03-01
Some general remarks about integral transform approaches to response functions are made. Their advantage for calculating cross sections at energies in the continuum is stressed. In particular we discuss the class of kernels that allow calculations of the transform by matrix diagonalization. A particular set of such kernels, namely the wavelets, is tested in a model study.
Alternative representation of the linear canonical integral transform
NASA Astrophysics Data System (ADS)
Alieva, Tatiana; Bastiaans, Martin J.
2005-12-01
Starting with the Iwasawa-type decomposition of a first-order optical system (or ABCD system) as a cascade of a lens, a magnifier, and an orthosymplectic system (a system that is both symplectic and orthogonal), a further decomposition of the orthosymplectic system in the form of a separable fractional Fourier transformer embedded between two spatial-coordinate rotators is proposed. The resulting decomposition of the entire first-order optical system then shows a physically attractive representation of the linear canonical integral transformation, which, in contrast to Collins integral, is valid for any ray transformation matrix.
Study of {sup 3}He(e,e{prime}) longitudinal response functions with the integral-transform method
Dobretsov, V.Yu.; Efros, V.D.; Shao, B.
1995-09-01
The method of integral transforms is first applied to study of the {sup 3}He longitudinal response functions. The transforms are calculated from localized bound-state type solutions to an inhomogenous three-body equation. {sup 3}N dynamics and the conventional charge density operator serve as an input. The final-state interaction the contribution of the T = 3/2 final states to the problem suppressed and amounts to about 15%. This might be ascribed to symmetry properties of the final-state wave functions. The contributions of the p-wave N/N interaction and of the Coulomb interaction to the problem are studied and found to amount to several percent. Uncertainties due to different choices of s-wave NN forces are found to be of a similar magnitude. For q = 300 MeV/c, the results obtained agree with experiment. For q = 500 MeV/c, noticeable differences are detected. 20 refs., 3 figs.
Numerical approach to Coulomb gauge QCD
Matevosyan, Hrayr H.; Szczepaniak, Adam P.; Bowman, Patrick O.
2008-07-01
We calculate the ghost two-point function in Coulomb gauge QCD with a simple model vacuum gluon wave function using Monte Carlo integration. This approach extends the previous analytic studies of the ghost propagator with this ansatz, where a ladder-rainbow expansion was unavoidable for calculating the path integral over gluon field configurations. The new approach allows us to study the possible critical behavior of the coupling constant, as well as the Coulomb potential derived from the ghost dressing function. We demonstrate that IR enhancement of the ghost correlator or Coulomb form factor fails to quantitatively reproduce confinement using Gaussian vacuum wave functional.
Differential Galois theory and Darboux transformations for Integrable Systems
NASA Astrophysics Data System (ADS)
Jiménez, Sonia; Morales-Ruiz, Juan J.; Sánchez-Cauce, Raquel; Zurro, María-Angeles
2017-05-01
We apply the Differential Galois Theory of linear partial differential systems to the Bäcklund-Darboux transformations of the AKNS solitonic partial differential equations. We prove that the Galois group of the transformed system is isomorphic to a subgroup of the Galois group of the initial system. As an example, we study the integrability in closed form of the linear systems corresponding to the solitonic solutions of KdV equation.
DNA transformations of Candida tropicalis with replicating and integrative vectors.
Sanglard, D; Fiechter, A
1992-12-01
The alkane-assimilating yeast Candida tropicalis was used as a host for DNA transformations. A stable ade2 mutant (Ha900) obtained by UV-mutagenesis was used as a recipient for different vectors carrying selectable markers. A first vector, pMK16, that was developed for the transformation of C. albicans and carries an ADE2 gene marker and a Candida autonomously replicating sequence (CARS) element promoting autonomous replication, was compatible for transforming Ha900. Two transformant types were observed: (i) pink transformants which easily lose pMK16 under non-selective growth conditions; (ii) white transformants, in which the same plasmid exhibited a higher mitotic stability. In both cases pMK16 could be rescued from these cells in Escherichia coli. A second vector, pADE2, containing the isolated C. tropicalis ADE2, gene, was used to transform Ha900. This vector integrated in the yeast genome at homologous sites of the ade2 locus. Different integration types were observed at one or both ade2 alleles in single or in tandem repeats.
A Dynamic Integrated Fault Diagnosis Method for Power Transformers
Gao, Wensheng; Liu, Tong
2015-01-01
In order to diagnose transformer fault efficiently and accurately, a dynamic integrated fault diagnosis method based on Bayesian network is proposed in this paper. First, an integrated fault diagnosis model is established based on the causal relationship among abnormal working conditions, failure modes, and failure symptoms of transformers, aimed at obtaining the most possible failure mode. And then considering the evidence input into the diagnosis model is gradually acquired and the fault diagnosis process in reality is multistep, a dynamic fault diagnosis mechanism is proposed based on the integrated fault diagnosis model. Different from the existing one-step diagnosis mechanism, it includes a multistep evidence-selection process, which gives the most effective diagnostic test to be performed in next step. Therefore, it can reduce unnecessary diagnostic tests and improve the accuracy and efficiency of diagnosis. Finally, the dynamic integrated fault diagnosis method is applied to actual cases, and the validity of this method is verified. PMID:25685841
A dynamic integrated fault diagnosis method for power transformers.
Gao, Wensheng; Bai, Cuifen; Liu, Tong
2015-01-01
In order to diagnose transformer fault efficiently and accurately, a dynamic integrated fault diagnosis method based on Bayesian network is proposed in this paper. First, an integrated fault diagnosis model is established based on the causal relationship among abnormal working conditions, failure modes, and failure symptoms of transformers, aimed at obtaining the most possible failure mode. And then considering the evidence input into the diagnosis model is gradually acquired and the fault diagnosis process in reality is multistep, a dynamic fault diagnosis mechanism is proposed based on the integrated fault diagnosis model. Different from the existing one-step diagnosis mechanism, it includes a multistep evidence-selection process, which gives the most effective diagnostic test to be performed in next step. Therefore, it can reduce unnecessary diagnostic tests and improve the accuracy and efficiency of diagnosis. Finally, the dynamic integrated fault diagnosis method is applied to actual cases, and the validity of this method is verified.
New four-dimensional integrals by Mellin-Barnes transform
Allendes, Pedro; Guerrero, Natanael; Kondrashuk, Igor; Notte Cuello, Eduardo A.
2010-05-15
This paper is devoted to the calculation of a special class of integrals by Mellin-Barnes transform. It contains double integrals in the position space in d=4-2{epsilon} dimensions, where {epsilon} is parameter of dimensional regularization. These integrals contribute to the effective action of the N=4 supersymmetric Yang-Mills theory. The integrand is a fraction in which the numerator is the logarithm of the ratio of space-time intervals, and the denominator is the product of powers of space-time intervals. According to the method developed in the previous papers, in order to make use of the uniqueness technique for one of two integrations, we shift exponents in powers in the denominator of integrands by some multiples of {epsilon}. As the next step, the second integration in the position space is done by Mellin-Barnes transform. For normalizing procedure, we reproduce first the known result obtained earlier by Gegenbauer polynomial technique. Then, we make another shift of exponents in powers in the denominator to create the logarithm in the numerator as the derivative with respect to the shift parameter {delta}. We show that the technique of work with the contour of the integral modified in this way by using Mellin-Barnes transform repeats the technique of work with the contour of the integral without such a modification. In particular, all the operations with a shift of contour of integration over complex variables of twofold Mellin-Barnes transform are the same as before the {delta} modification of indices, and even the poles of residues coincide. This confirms the observation made in the previous papers that in the position space all the Green's function of N=4 supersymmetric Yang-Mills theory can be expressed in terms of Usyukina-Davydychev functions.
Exploring Conditions for Transformative Learning in Work-Integrated Education
ERIC Educational Resources Information Center
McRae, Norah
2015-01-01
A qualitative study was undertaken that explored the conditions for transformative learning in cooperative education as a form of work-integrated learning (WIL), towards the development of a theoretical model. Four case studies were analyzed based on interviews with WIL students, supervisors and their co-op coordinator. The findings revealed that…
Complexity estimates based on integral transforms induced by computational units.
Kůrková, Věra
2012-09-01
Integral transforms with kernels corresponding to computational units are exploited to derive estimates of network complexity. The estimates are obtained by combining tools from nonlinear approximation theory and functional analysis together with representations of functions in the form of infinite neural networks. The results are applied to perceptron networks.
Efficient Integration of Quantum Mechanical Wave Equations by Unitary Transforms
Bauke, Heiko; Keitel, Christoph H.
2009-08-13
The integration of time dependent quantum mechanical wave equations is a fundamental problem in computational physics and computational chemistry. The energy and momentum spectrum of a wave function imposes fundamental limits on the performance of numerical algorithms for this problem. We demonstrate how unitary transforms can help to surmount these limitations.
The Effects of Integrated Transformational Leadership on Achievement
ERIC Educational Resources Information Center
Boberg, John Eric; Bourgeois, Steven J.
2016-01-01
Purpose: Greater understanding about how variables mediate the relationship between leadership and achievement is essential to the success of reform efforts that hold leaders accountable for student learning. The purpose of this paper is to test a model of integrated transformational leadership including three important school mediators.…
The Effects of Integrated Transformational Leadership on Achievement
ERIC Educational Resources Information Center
Boberg, John Eric; Bourgeois, Steven J.
2016-01-01
Purpose: Greater understanding about how variables mediate the relationship between leadership and achievement is essential to the success of reform efforts that hold leaders accountable for student learning. The purpose of this paper is to test a model of integrated transformational leadership including three important school mediators.…
Transforming the Economics Curriculum by Integrating Threshold Concepts
ERIC Educational Resources Information Center
Karunaratne, Prashan Shayanka Mendis; Breyer, Yvonne A.; Wood, Leigh N.
2016-01-01
Purpose: Economics is catering to a diverse student cohort. This cohort needs to be equipped with transformative concepts that students can integrate beyond university. When a curriculum is content-driven, threshold concepts are a useful tool in guiding curriculum re-design. The paper aims to discuss these issues. Design/Methodology/Approach: The…
Transforming the Economics Curriculum by Integrating Threshold Concepts
ERIC Educational Resources Information Center
Karunaratne, Prashan Shayanka Mendis; Breyer, Yvonne A.; Wood, Leigh N.
2016-01-01
Purpose: Economics is catering to a diverse student cohort. This cohort needs to be equipped with transformative concepts that students can integrate beyond university. When a curriculum is content-driven, threshold concepts are a useful tool in guiding curriculum re-design. The paper aims to discuss these issues. Design/Methodology/Approach: The…
Analysis of integral method for fault detection in transformers
Hijazi, M.E.A.; Basak, A. . Wolfson Centre for Magnetics Technology)
1993-11-01
Test results obtained from using the integral method in transformer differential protection against internal fault current, are presented. The effect of various factors on the transient waveforms are considered and conditions to predict the magnetizing inrush current and a faulty system have been digitally simulated.
Integration of a piezoelectric transformer and an ultrasonic motor.
Manuspiya, Suwan; Laoratanakul, Pitak; Uchino, Kenji
2003-03-01
Ultrasonic motors are usually operated at an AC voltage higher than a regular battery. This implies the need of a voltage step-up transformer. In this paper, we report the integration of a piezoelectric transformer (PT) with an ultrasonic motor and a simple drive circuit. The stator of the ultrasonic motor and the PT were operated in the same radial vibration mode. Their dimensions were very close to each other yielding nearly matching resonance frequencies. Consequently, they could be combined together without inductor. The drive circuit was designed by using a 555 timer as an astable multivibrator, and high-speed dual MOSFET drivers as a class D half-bridge switching amplifier. This integrated PT-ultrasonic motor performed reasonably without the use of electromagnetic transformer or inductor. Copyright 2002 Elsevier Science B.V.
Transformational leadership and team innovation: integrating team climate principles.
Eisenbeiss, Silke A; van Knippenberg, Daan; Boerner, Sabine
2008-11-01
Fostering team innovation is increasingly an important leadership function. However, the empirical evidence for the role of transformational leadership in engendering team innovation is scarce and mixed. To address this issue, the authors link transformational leadership theory to principles of M. A. West's (1990) team climate theory and propose an integrated model for the relationship between transformational leadership and team innovation. This model involves support for innovation as a mediating process and climate for excellence as a moderator. Results from a study of 33 research and development teams confirmed that transformational leadership works through support for innovation, which in turn interacts with climate for excellence such that support for innovation enhances team innovation only when climate for excellence is high.
Wang, Bin; Gao, Yongsheng
2016-12-01
In this paper, we present a novel mathematical tool, Structure Integral Transform (SIT), for invariant shape description and recognition. Different from the Radon Transform (RT), which integrates the shape image function over a 1D line in the image plane, the proposed SIT builds upon two orthogonal integrals over a 2D K -cross dissecting structure spanning across all rotation angles by which the shape regions are bisected in each integral. The proposed SIT brings the following advantages over the RT: 1) it has the extra function of describing the interior structural relationship within the shape which provides a more powerful discriminative ability for shape recognition; 2) the shape regions are dissected by the K -cross in a coarse to fine hierarchical order that can characterize the shape in a better spatial organization scanning from the center to the periphery; and 3) it is easier to build a completely invariant shape descriptor. The experimental results of applying SIT to shape recognition demonstrate its superior performance over the well-known Radon transform, and the well-known shape contexts and the polar harmonic transforms.
ERIC Educational Resources Information Center
Noll, Ellis; Koehlinger, Mervin; Kowalski, Ludwik; Swackhamer, Gregg
1998-01-01
Describes the use of a computer-linked camera to demonstrate Coulomb's law. Suggests a way of reducing the difficulties in presenting Coulomb's law by teaching the inverse square law of gravity and the inverse square law of electricity in the same unit. (AIM)
Diffusion in Coulomb crystals.
Hughto, J; Schneider, A S; Horowitz, C J; Berry, D K
2011-07-01
Diffusion in Coulomb crystals can be important for the structure of neutron star crusts. We determine diffusion constants D from molecular dynamics simulations. We find that D for Coulomb crystals with relatively soft-core 1/r interactions may be larger than D for Lennard-Jones or other solids with harder-core interactions. Diffusion, for simulations of nearly perfect body-centered-cubic lattices, involves the exchange of ions in ringlike configurations. Here ions "hop" in unison without the formation of long lived vacancies. Diffusion, for imperfect crystals, involves the motion of defects. Finally, we find that diffusion, for an amorphous system rapidly quenched from Coulomb parameter Γ=175 to Coulomb parameters up to Γ=1750, is fast enough that the system starts to crystalize during long simulation runs. These results strongly suggest that Coulomb solids in cold white dwarf stars, and the crust of neutron stars, will be crystalline and not amorphous.
Hughto, J.; Schneider, A. S.; Horowitz, C. J.; Berry, D. K.
2011-07-15
Diffusion in Coulomb crystals can be important for the structure of neutron star crusts. We determine diffusion constants D from molecular dynamics simulations. We find that D for Coulomb crystals with relatively soft-core 1/r interactions may be larger than D for Lennard-Jones or other solids with harder-core interactions. Diffusion, for simulations of nearly perfect body-centered-cubic lattices, involves the exchange of ions in ringlike configurations. Here ions ''hop'' in unison without the formation of long lived vacancies. Diffusion, for imperfect crystals, involves the motion of defects. Finally, we find that diffusion, for an amorphous system rapidly quenched from Coulomb parameter {Gamma}=175 to Coulomb parameters up to {Gamma}=1750, is fast enough that the system starts to crystalize during long simulation runs. These results strongly suggest that Coulomb solids in cold white dwarf stars, and the crust of neutron stars, will be crystalline and not amorphous.
Implementing quantum Fourier transform with integrated photonic devices
NASA Astrophysics Data System (ADS)
Tabia, Gelo Noel
2014-03-01
Many quantum algorithms that exhibit exponential speedup over their classical counterparts employ the quantum Fourier transform, which is used to solve interesting problems such as prime factorization. Meanwhile, nonclassical interference of single photons achieved on integrated platforms holds the promise of achieving large-scale quantum computation with multiport devices. An optical multiport device can be built to realize any quantum circuit as a sequence of unitary operations performed by beam splitters and phase shifters on path-encoded qudits. In this talk, I will present a recursive scheme for implementing quantum Fourier transform with a multimode interference photonic integrated circuit. Research at Perimeter Institute is supported by the Government of Canada through Industry Canada and by the Province of Ontario through the Ministry of Research and Innovation.
Linearization properties, first integrals, nonlocal transformation for heat transfer equation
NASA Astrophysics Data System (ADS)
Orhan, Özlem; Özer, Teoman
2016-08-01
We examine first integrals and linearization methods of the second-order ordinary differential equation which is called fin equation in this study. Fin is heat exchange surfaces which are used widely in industry. We analyze symmetry classification with respect to different choices of thermal conductivity and heat transfer coefficient functions of fin equation. Finally, we apply nonlocal transformation to fin equation and examine the results for different functions.
Greater benefits of multisensory integration during complex sensorimotor transformations.
Buchholz, Verena N; Goonetilleke, Samanthi C; Medendorp, W Pieter; Corneil, Brian D
2012-06-01
Multisensory integration enables rapid and accurate behavior. To orient in space, sensory information registered initially in different reference frames has to be integrated with the current postural information to produce an appropriate motor response. In some postures, multisensory integration requires convergence of sensory evidence across hemispheres, which would presumably lessen or hinder integration. Here, we examined orienting gaze shifts in humans to visual, tactile, or visuotactile stimuli when the hands were either in a default uncrossed posture or a crossed posture requiring convergence across hemispheres. Surprisingly, we observed the greatest benefits of multisensory integration in the crossed posture, as indexed by reaction time (RT) decreases. Moreover, such shortening of RTs to multisensory stimuli did not come at the cost of increased error propensity. To explain these results, we propose that two accepted principles of multisensory integration, the spatial principle and inverse effectiveness, dynamically interact to aid the rapid and accurate resolution of complex sensorimotor transformations. First, early mutual inhibition of initial visual and tactile responses registered in different hemispheres reduces error propensity. Second, inverse effectiveness in the integration of the weakened visual response with the remapped tactile representation expedites the generation of the correct motor response. Our results imply that the concept of inverse effectiveness, which is usually associated with external stimulus properties, might extend to internal spatial representations that are more complex given certain body postures.
Singular integrals related to the Radon transform and boundary value problems.
Phong, D H; Stein, E M
1983-12-01
Two classes of integral operators are introduced that combine features of Calderón-Zygmund singular integrals, the Hilbert integral, and the Radon transform. Examples and applications arising from integral geometry and several complex variables are discussed.
Singular integrals related to the Radon transform and boundary value problems
Phong, D. H.; Stein, E. M.
1983-01-01
Two classes of integral operators are introduced that combine features of Calderón—Zygmund singular integrals, the Hilbert integral, and the Radon transform. Examples and applications arising from integral geometry and several complex variables are discussed. PMID:16593402
Federal Register 2010, 2011, 2012, 2013, 2014
2011-10-14
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Nahm transform for integrable connections on the Riemann sphere
NASA Astrophysics Data System (ADS)
Szabo, Szilard
2005-11-01
In this work we are concerned with reduction of the ASD-equations to the Riemann sphere, that is integrable connections with a harmonic metric, or equivalently Higgs bundles with a Hermitian-Einstein metric. In the first chapter, we introduce the type of singularities we allow for the solutions to have, and announce the main results of the paper. In the second chapter, we study the analytical properties of the Dirac and Green's operators of our problem. In the third one, we carry out the main construction of the paper, namely that of the Nahm transform of an integrable connection with parabolic structure and with a compatible harmonic metric. In the fourth chapter, we interpret the construction from the point of view of Higgs bundles, and compute the effect of the transform on the level of topological and singularity parameters - this latter being achieved via an understanding of the behaviour of the spectral curve. Finally, in the fifth chapter we show that Nahm transform is (up to a sign) an involution.
New approach to folding with the Coulomb wave function
Blokhintsev, L. D.; Savin, D. A.; Kadyrov, A. S.; Mukhamedzhanov, A. M.
2015-05-15
Due to the long-range character of the Coulomb interaction theoretical description of low-energy nuclear reactions with charged particles still remains a formidable task. One way of dealing with the problem in an integral-equation approach is to employ a screened Coulomb potential. A general approach without screening requires folding of kernels of the integral equations with the Coulomb wave. A new method of folding a function with the Coulomb partial waves is presented. The partial-wave Coulomb function both in the configuration and momentum representations is written in the form of separable series. Each term of the series is represented as a product of a factor depending only on the Coulomb parameter and a function depending on the spatial variable in the configuration space and the momentum variable if the momentum representation is used. Using a trial function, the method is demonstrated to be efficient and reliable.
Experimental Evaluation of Integral Transformations for Engineering Drawings Vectorization
NASA Astrophysics Data System (ADS)
Vaský, Jozef; Gramblička, Matúš
2014-12-01
The concept of digital manufacturing supposes application of digital technologies in the whole product life cycle. Direct digital manufacturing includes such information technology processes, where products are directly manufactured from 3D CAD model. In digital manufacturing, engineering drawing is replaced by CAD product model. In the contemporary practice, lots of engineering paper-based drawings are still archived. They could be digitalized by scanner and stored to one of the raster graphics format and after that vectorized for interactive editing in the specific software system for technical drawing or for archiving in some of the standard vector graphics file format. The vector format is suitable for 3D model generating, too.The article deals with using of selected integral transformations (Fourier, Hough) in the phase of digitalized raster engineering drawings vectorization.
Solution of Coulomb system in momentum space
Lin, D.-H.
2008-02-15
The solution of D-dimensional Coulomb system is solved in momentum space by path integral. From which the topological effect of a magnetic flux in the system is given. It is revealed that the flux effect represented by the two-dimensional field of Aharonov-Bohm covers any space-dimensions.
Coulomb gauge ghost propagator and the Coulomb form factor
NASA Astrophysics Data System (ADS)
Quandt, M.; Burgio, G.; Chimchinda, S.; Reinhardt, H.
The ghost propagator and the Coulomb potential are evaluated in Coulomb gauge on the lattice, using an improved gauge fixing scheme which includes the residual symmetry. This setting has been shown to be essential in order to explain the scaling violations in the instantaneous gluon propagator. We find that both the ghost propagator and the Coulomb potential are insensitive to the Gribov problem or the details of the residual gauge fixing, even if the Coulomb potential is evaluated from the A0 -propagator instead of the Coulomb kernel. In particular, no signs of scaling violations could be found in either quantity, at least to well below the numerical accuracy where these violations were visible for the gluon propagator. The Coulomb potential from the A0 -propagator is shown to be in qualitative agreement with the (formally equivalent) expression evaluated from the Coulomb kernel.
NASA Astrophysics Data System (ADS)
Militzer, Burkhard
2003-06-01
Path integral Monte Carlo simulations have been used to study deuterium at high pressure and temperature. The equation of state has been derived in the temperature and density regions of 10 000 leq T leq 1 000 000 K and 0.6 leq rho leq 2.5 g cm-3. A series of shock Hugoniot curves is computed for different initial compressions in order to compare with current and future shock wave experiments using liquid deuterium samples precompressed in diamond anvil cells. Submitted to Proceedings of the Conference on Strongly Coupled Coulomb Systems 2002 in Santa Fe.
Learning Multisensory Integration and Coordinate Transformation via Density Estimation
Sabes, Philip N.
2013-01-01
Sensory processing in the brain includes three key operations: multisensory integration—the task of combining cues into a single estimate of a common underlying stimulus; coordinate transformations—the change of reference frame for a stimulus (e.g., retinotopic to body-centered) effected through knowledge about an intervening variable (e.g., gaze position); and the incorporation of prior information. Statistically optimal sensory processing requires that each of these operations maintains the correct posterior distribution over the stimulus. Elements of this optimality have been demonstrated in many behavioral contexts in humans and other animals, suggesting that the neural computations are indeed optimal. That the relationships between sensory modalities are complex and plastic further suggests that these computations are learned—but how? We provide a principled answer, by treating the acquisition of these mappings as a case of density estimation, a well-studied problem in machine learning and statistics, in which the distribution of observed data is modeled in terms of a set of fixed parameters and a set of latent variables. In our case, the observed data are unisensory-population activities, the fixed parameters are synaptic connections, and the latent variables are multisensory-population activities. In particular, we train a restricted Boltzmann machine with the biologically plausible contrastive-divergence rule to learn a range of neural computations not previously demonstrated under a single approach: optimal integration; encoding of priors; hierarchical integration of cues; learning when not to integrate; and coordinate transformation. The model makes testable predictions about the nature of multisensory representations. PMID:23637588
Feynman rules for Coulomb gauge QCD
Andrasi, A.; Taylor, J.C.
2012-10-15
The Coulomb gauge in nonabelian gauge theories is attractive in principle, but beset with technical difficulties in perturbation theory. In addition to ordinary Feynman integrals, there are, at 2-loop order, Christ-Lee (CL) terms, derived either by correctly ordering the operators in the Hamiltonian, or by resolving ambiguous Feynman integrals. Renormalization theory depends on the sub-graph structure of ordinary Feynman graphs. The CL terms do not have a sub-graph structure. We show how to carry out renormalization in the presence of CL terms, by re-expressing these as 'pseudo-Feynman' integrals. We also explain how energy divergences cancel. - Highlights: Black-Right-Pointing-Pointer In Coulomb gauge QCD, we re-express Christ-Lee terms in the Hamiltonian as pseudo-Feynman integrals. Black-Right-Pointing-Pointer This gives a subgraph structure, and allows the ordinary renormalization process. Black-Right-Pointing-Pointer It also leads to cancellation of energy-divergences.
2001-03-01
A unique ASIC was designed implementing the Haar Wavelet transform for image compression/decompression. ASIC operations include performing the Haar... wavelet transform on a 512 by 512 square pixel image, preparing the image for transmission by quantizing and thresholding the transformed data, and...performing the inverse Haar wavelet transform , returning the original image with only minor degradation. The ASIC is based on an existing four-chip FPGA
Polonyi, J.
2008-06-15
The contribution of different modes of the Coulomb field to decoherence and to the dynamical breakdown of the time reversal invariance is calculated in the one-loop approximation for nonrelativistic electron gas. The dominant contribution was found to come from the usual collective modes in the plasma, namely, the zero-sound and the plasmon oscillations. The length scale of the quantum-classical transition is found to be close to the Thomas-Fermi screening length. It is argued that the extension of these modes to the whole Fock space yields optimal pointer states.
An integro-differential transform to analytically reduce H2 molecular integrals
NASA Astrophysics Data System (ADS)
Straton, Jack
2012-06-01
Molecular integrals that have a coordinate dependence akin to the bonding H2 wave function are often carried out one-by-one, using hyper-spherical coordinates [1], Jacobi coordinates or bond-length coordinates [2], or confocal ellipsoidal coordinates [3]. An alternative strategy is to extend the general result developed by the author [4] for evaluating integrals of any number of products of multicenter ground-state or excited [5] atomic wave functions, Coulomb or Yukawa potentials, and Coulomb-waves [6] to include the H2 molecular wave function. Modifications for semi-infinite integrals that terminate on a surface such as a Scanning Tunneling Microscope sample are also discussed. [4pt] [1] Y. Zhou, C. D. Lin and J. Shertzer, J. Phys. B: At. Mol. Opt. Phys. 26, 3937-3949 (1993).[0pt] [2] J. M. Hutson and P. Soldan, International Reviews in Physical Chemistry, 26(1) 1 - 28 (January 2007).[0pt] [3] J. P. Grivet, J. Chem. Educ., 79(1), 127 (2002).[0pt] [4] Jack C. Straton, Phys. Rev. A 39, 1676-84 (1989); Erratum Phys. Rev. A 40, 2819 (1989).[0pt] [5] Jack C. Straton, Phys. Rev. A 41, 71-7 (1990).[0pt] [6] Jack C. Straton, Phys. Rev. A 42, 307-10 (1990).
On integral and finite Fourier transforms of continuous q-Hermite polynomials
Atakishiyeva, M. K.; Atakishiyev, N. M.
2009-05-15
We give an overview of the remarkably simple transformation properties of the continuous q-Hermite polynomials H{sub n}(x vertical bar q) of Rogers with respect to the classical Fourier integral transform. The behavior of the q-Hermite polynomials under the finite Fourier transform and an explicit form of the q-extended eigenfunctions of the finite Fourier transform, defined in terms of these polynomials, are also discussed.
NASA Astrophysics Data System (ADS)
Gaughan, Daniel J.
1990-12-01
This research was performed in order to develop a superior processing schedule for fabricating wafer-scale integration (WSI) circuit modules. This technology allows the design of circuitry that spans the entire surface of a silicon substrate wafer. The circuit element employed in this research was the Hilbert transform, a digital phase-shifting circuit. The transform was incorporated into a three integrated circuit (IC) die package that consisted of a mechanically supportive silicon wafer, three IC die, and a planarizing silicon wafer. The die were epoxied into this wafer using a Teflon block as a flat, and the combination was epoxied onto the substrate wafer, forming the IC module. The original design goals of this research were to keep the IC die and wafer planar and to electrically characterize of the module's interconnections. The first goal was met; the resultant process uses a low temperature (50 C) cure to achieve die-to-wafer planarity of within 5 microns. The second was not met due to the inability to pattern the chosen photosensitive dielectric material. Recommendations for further research included the need to use a stable non-stick surface as a epoxy cure fixture and the need to investigate the photopatternable dielectric material.
Ziegler, Brittany; Montplaisir, Lisa
2012-12-01
A shift is currently taking place in which explicit connections between content are being emphasized. Biology is not an isolated discipline, yet undergraduate courses frequently focus on discrete knowledge. Students often engage in rote learning, struggle with transforming and applying content. Integrative thinking occurs when students recognize connections to content. Written reflections provide students with the opportunity to demonstrate this thinking. We transformed student-written reflections into concept webs to gain insights into how students connect biological concepts. We were interested in determining if characteristics of integrative thinking develop through reflections. The results indicate a significant relationship between concepts and integrated relationships. Integrative thinking varied but declined overall. Concept webs allow for an examination of student integrative thinking through the transformation of reflection and provide insights into the connections and relationships that students draw between biological concepts. Reflections can transform learning by facilitating and allowing for the evaluation of integrative thinking.
Envelope representations for screened Coulomb potentials
NASA Astrophysics Data System (ADS)
Hall, Richard L.
1985-07-01
We study the discrete eigenvalues Enl of the Schrödinger Hamiltonian H=-(1/2)Δ+V(r), where V(r)=g(-1/r) is an increasing concave transformation of the Coulomb potential, and n is the principal (radial) quantum number. It is demonstrated by the method of potential envelopes that upper bounds are provided by the simple formula Enl<= mins>0 \\{(1/2)s+V((n+l)/s1/2)\\}, where s is a real variable. Numerical results are compared with previous work for two specific screened Coulomb potentials. In the case of the Yukawa potential V(r)=-(v/r)exp(-λr), it is shown that the inequality (n+l)2λ/v<2/e is sufficient to guarantee the existence of the eigenvalue Enl: In the case of S states, sharp upper and lower bounds are also provided by a different method.
Wang, Bo; Yu, Jianping
2015-01-01
Restriction digestion of foreign DNA is one of the key biological barriers against genetic transformation in microorganisms. To establish a high-efficiency transformation protocol in the model cyanobacterium, Synechocystis sp. strain PCC 6803 (Synechocystis 6803), we investigated the effects of premethylation of foreign DNA on the integrative transformation of this strain. In this study, two type II methyltransferase-encoding genes, i.e., sll0729 (gene M) and slr0214 (gene C), were cloned from the chromosome of Synechocystis 6803 and expressed in Escherichia coli harboring an integration plasmid. After premethylation treatment in E. coli, the integration plasmid was extracted and used for transformation of Synechocystis 6803. The results showed that although expression of methyltransferase M had little impact on the transformation of Synechocystis 6803, expression of methyltransferase C resulted in 11- to 161-fold-higher efficiency in the subsequent integrative transformation of Synechocystis 6803. Effective expression of methyltransferase C, which could be achieved by optimizing the 5′ untranslated region, was critical to efficient premethylation of the donor DNA and thus high transformation efficiency in Synechocystis 6803. Since premethylating foreign DNA prior to transforming Synechocystis avoids changing the host genetic background, the study thus provides an improved method for high-efficiency integrative transformation of Synechocystis 6803. PMID:26452551
Wang, Bo; Yu, Jianping; Zhang, Weiwen; Meldrum, Deirdre R
2015-12-01
Restriction digestion of foreign DNA is one of the key biological barriers against genetic transformation in microorganisms. To establish a high-efficiency transformation protocol in the model cyanobacterium, Synechocystis sp. strain PCC 6803 (Synechocystis 6803), we investigated the effects of premethylation of foreign DNA on the integrative transformation of this strain. In this study, two type II methyltransferase-encoding genes, i.e., sll0729 (gene M) and slr0214 (gene C), were cloned from the chromosome of Synechocystis 6803 and expressed in Escherichia coli harboring an integration plasmid. After premethylation treatment in E. coli, the integration plasmid was extracted and used for transformation of Synechocystis 6803. The results showed that although expression of methyltransferase M had little impact on the transformation of Synechocystis 6803, expression of methyltransferase C resulted in 11- to 161-fold-higher efficiency in the subsequent integrative transformation of Synechocystis 6803. Effective expression of methyltransferase C, which could be achieved by optimizing the 5' untranslated region, was critical to efficient premethylation of the donor DNA and thus high transformation efficiency in Synechocystis 6803. Since premethylating foreign DNA prior to transforming Synechocystis avoids changing the host genetic background, the study thus provides an improved method for high-efficiency integrative transformation of Synechocystis 6803. Copyright © 2015, American Society for Microbiology. All Rights Reserved.
Traceable Coulomb blockade thermometry
NASA Astrophysics Data System (ADS)
Hahtela, O.; Mykkänen, E.; Kemppinen, A.; Meschke, M.; Prunnila, M.; Gunnarsson, D.; Roschier, L.; Penttilä, J.; Pekola, J.
2017-02-01
We present a measurement and analysis scheme for determining traceable thermodynamic temperature at cryogenic temperatures using Coulomb blockade thermometry. The uncertainty of the electrical measurement is improved by utilizing two sampling digital voltmeters instead of the traditional lock-in technique. The remaining uncertainty is dominated by that of the numerical analysis of the measurement data. Two analysis methods are demonstrated: numerical fitting of the full conductance curve and measuring the height of the conductance dip. The complete uncertainty analysis shows that using either analysis method the relative combined standard uncertainty (k = 1) in determining the thermodynamic temperature in the temperature range from 20 mK to 200 mK is below 0.5%. In this temperature range, both analysis methods produced temperature estimates that deviated from 0.39% to 0.67% from the reference temperatures provided by a superconducting reference point device calibrated against the Provisional Low Temperature Scale of 2000.
The Impact of Technology Integration through a Transformative Approach
ERIC Educational Resources Information Center
Cubillos, Jo Ann
2013-01-01
The integration of technology into classroom instruction in K-12 schools remains problematic. The problems associated with this integration are troubling, as technology integration may change a teacher's pedagogy toward more innovative approaches that increase student achievement. The purpose of this study was to document teachers' experiences as…
The Impact of Technology Integration through a Transformative Approach
ERIC Educational Resources Information Center
Cubillos, Jo Ann
2013-01-01
The integration of technology into classroom instruction in K-12 schools remains problematic. The problems associated with this integration are troubling, as technology integration may change a teacher's pedagogy toward more innovative approaches that increase student achievement. The purpose of this study was to document teachers' experiences as…
NASA Astrophysics Data System (ADS)
McCallum, Matthew S.
An integral transform which reproduces a transformable input function after a finite number N of successive applications is known as a cyclic transform. Of course, such a transform will reproduce an arbitrary transformable input after N applications, but it also admits eigenfunction inputs which will be reproduced after a single application of the transform. These transforms and their eigenfunctions appear in various applications, and the systematic determination of eigenfunctions of cyclic integral transforms has been a problem of interest to mathematicians since at least the early twentieth century. In this work we review the various approaches to this problem, providing generalizations of published expressions from previous approaches. We then develop a new formalism, differential eigenoperators, that reduces the eigenfunction problem for a cyclic transform to an eigenfunction problem for a corresponding ordinary differential equation. In this way we are able to relate eigenfunctions of integral equations to boundary-value problems, which are typically easier to analyze. We give extensive examples and discussion via the specific case of the Fourier transform. We also relate this approach to two formalisms that have been of interest to the mathematical physics community---hyperdifferential operators and linear canonical transforms. We show how this new approach reproduces known results of Fourier optics regarding free-space diffractive propagation of Gaussian beams in both one and two dimensions. Finally we discuss the group-theoretical aspects of the formalism and describe an isomorphism between roots of the identity transform and complex roots of unity. In the appendix we derive several technical results related to integrability and transformability of solutions in the Fourier transform case, and we prove two theorems---one of them new---on polynomial roots. We conclude that the formalism offers a new and equally valuable perspective on an interesting
Energies of Screened Coulomb Potentials.
ERIC Educational Resources Information Center
Lai, C. S.
1979-01-01
This article shows that, by applying the Hellman-Feynman theorem alone to screened Coulomb potentials, the first four coefficients in the energy series in powers of the perturbation parameter can be obtained from the unperturbed Coulomb system. (Author/HM)
Coulomb blockade and Coulomb staircase behavior observed at room temperature
NASA Astrophysics Data System (ADS)
Uky Vivitasari, Pipit; Azuma, Yasuo; Sakamoto, Masanori; Teranishi, Toshiharu; Majima, Yutaka
2017-02-01
A single-electron transistor (SET) consists of source, drain, Coulomb island, and gate to modulate the number of electrons and control the current. For practical applications, it is important to operate a SET at room temperature. One proposal towards the ability to operate at room temperature is to decrease Coulomb island size down to a few nanometres. We investigate a SET using Sn-porphyrin (Sn-por) protected gold nanoparticles (AuNPs) with 1.4 nm in core diameter as a Coulomb island. The fabrication method of nanogap electrodes uses the combination of a top-down technique by electron beam lithography (EBL) and a bottom-up process through electroless gold plating (ELGP) as our group have described before. The electrical measurement was conducted at room temperature (300 K). From current-voltage (I d-V d) characteristics, we obtained clear Coulomb blockade phenomena together with a Coulomb staircase due to a Sn-por protected gold NP as a Coulomb island. Experimental results of I d-V d characteristics agree with a theoretical curve based on using the orthodox model. Clear dI d/dV d peaks are observed in the Coulomb staircase at 9 K which suggest the electron transports through excited energy levels of Au NPs. These results are a big step for obtaining SETs that can operate at room temperature.
Solution of fractional kinetic equation by a class of integral transform of pathway type
NASA Astrophysics Data System (ADS)
Kumar, Dilip
2013-04-01
Solutions of fractional kinetic equations are obtained through an integral transform named Pα-transform introduced in this paper. The Pα-transform is a binomial type transform containing many class of transforms including the well known Laplace transform. The paper is motivated by the idea of pathway model introduced by Mathai [Linear Algebra Appl. 396, 317-328 (2005), 10.1016/j.laa.2004.09.022]. The composition of the transform with differential and integral operators are proved along with convolution theorem. As an illustration of applications to the general theory of differential equations, a simple differential equation is solved by the new transform. Being a new transform, the Pα-transform of some elementary functions as well as some generalized special functions such as H-function, G-function, Wright generalized hypergeometric function, generalized hypergeometric function, and Mittag-Leffler function are also obtained. The results for the classical Laplace transform is retrieved by letting α → 1.
ERIC Educational Resources Information Center
Chatterjee, B.; Dey, D.; Chakravorti, S.
2010-01-01
The development of integrated, portable, transformer condition monitoring (TCM) equipment for classroom demonstrations as well as for student exercises conducted in the field is discussed. Demonstrations include experimentation with real-world transformers to illustrate concepts such as polarization and depolarization current through oil-paper…
ERIC Educational Resources Information Center
Chatterjee, B.; Dey, D.; Chakravorti, S.
2010-01-01
The development of integrated, portable, transformer condition monitoring (TCM) equipment for classroom demonstrations as well as for student exercises conducted in the field is discussed. Demonstrations include experimentation with real-world transformers to illustrate concepts such as polarization and depolarization current through oil-paper…
ERIC Educational Resources Information Center
Roth, George
2004-01-01
Reflection upon a field study of a corporate transformation provides insights into the application and integration of organizational learning theory and frameworks with local, corporate knowledge. In the corporate transformation studied this local knowledge came from consumer psychology, marketing campaigns and the use of media. When these ideas…
Integration of planar transformer and/or planar inductor with power switches in power converter
Chen, Kanghua; Ahmed, Sayeed; Zhu, Lizhi
2007-10-30
A power converter integrates at least one planar transformer comprising a multi-layer transformer substrate and/or at least one planar inductor comprising a multi-layer inductor substrate with a number of power semiconductor switches physically and thermally coupled to a heat sink via one or more multi-layer switch substrates.
ERIC Educational Resources Information Center
Roth, George
2004-01-01
Reflection upon a field study of a corporate transformation provides insights into the application and integration of organizational learning theory and frameworks with local, corporate knowledge. In the corporate transformation studied this local knowledge came from consumer psychology, marketing campaigns and the use of media. When these ideas…
The transformational model for professional practice: a system integration focus.
Wolf, Gail A; Hayden, Margaret; Bradle, Judith A
2004-04-01
Healthcare organizations face the increasingly difficult challenge of providing services that are of high quality, reasonable cost, and easy accessibility for their constituents. Mergers and acquisitions are one strategy for accomplishing this, but in doing so it is critical to have a "road map" to create an integrated system, rather than merely a consortium of hospitals. The University of Pittsburgh Medical Center has successfully created an integrated healthcare system of 19 hospitals. The authors describe the professional practice model used as a framework for success in integrating patient care.
Renormalization in the Coulomb gauge and order parameter for confinement in QCD
NASA Astrophysics Data System (ADS)
Zwanziger, Daniel
1998-05-01
Renormalization of the Coulomb gauge is studied in the phase space formalism, where one integrates over both the vector potential A, and its canonical momentum Π as well as the usual Faddeev-Popov auxiliary fields. A proof of renormalizability is not attempted. Instead, algebraic identities are derived from BRST invariance which renormalization must satisfy if the Coulomb gauge is renormalizable. In particular, a Ward identity is derived which holds at a fixed time t, and which is an analog of Gauss's law in the BRST formalism, and which we call the Gauss-BRST identity. The familiar Zinn-Justin equation results when this identity is integrated over all t. It is shown that in the Coulomb gauge, g2D0.0 is a renormalization-group invariant, as is its instantaneous part V( R), which we call the color-Coulomb potential. (Here D0.0 is the time-time component of the gluon propagator.) The contribution of V( R) to the Wilson loop exponentiates. It is proposed that the string tension defined by KCoul = lim R→∞ CV( R)/ R may serve as an order parameter for confinement, where C = (2 N) -1( N2 - 1) for SU( N) gauge theory. A remarkable consequence of the above-mentioned Ward identity is that the Fourier transform V( k) of V( R) is of the product form V( k) = [ k2D C,C ∗ ( k)] 2L( k) , where D C,C ∗ ( k) is the ghost propagator, and L( k) is a correlation function of longitudinal gluons. This exact equation combines with a previous analysis of the Gribov problem according to which k2D C,C ∗ ( k) diverges at k = 0 , to provide a scenario for confinement.
Coulomb excitation of radioactive nuclear beams in inverse kinematics
Zamfir, N.V. |||; Barton, C.J.; Brenner, D.S.; Casten, R.F. |; Gill, R.L.; Zilges, A. |
1996-12-31
Techniques for the measurement of B (E2:0{sub 1}{sup +} {r_arrow} 2{sub 1}{sup +}) values by Coulomb excitation of Radioactive Nuclear Beams in inverse kinematics are described. Using a thin, low Z target, the Coulomb excited beam nuclei will decay in flight downstream of the target. For long lifetimes (nanosecond range) these nuclei decay centimeters downstream of the target and for shorter lifetimes (picoseconds or less) they decay near the target. Corresponding to these two lifetime regimes two methods have been developed to measure {gamma} rays from the Coulomb excited nuclei: the lifetime method in which the lifetime of the excited state is deduced from the decay curve and the integral method in which the B(E2) value is extracted from the measured total Coulomb excitation cross section.
The Coulomb Branch of 3d N= 4 Theories
NASA Astrophysics Data System (ADS)
Bullimore, Mathew; Dimofte, Tudor; Gaiotto, Davide
2017-09-01
We propose a construction for the quantum-corrected Coulomb branch of a general 3d gauge theory with N=4 supersymmetry, in terms of local coordinates associated with an abelianized theory. In a fixed complex structure, the holomorphic functions on the Coulomb branch are given by expectation values of chiral monopole operators. We construct the chiral ring of such operators, using equivariant integration over BPS moduli spaces. We also quantize the chiral ring, which corresponds to placing the 3d theory in a 2d Omega background. Then, by unifying all complex structures in a twistor space, we encode the full hyperkähler metric on the Coulomb branch. We verify our proposals in a multitude of examples, including SQCD and linear quiver gauge theories, whose Coulomb branches have alternative descriptions as solutions to Bogomolnyi and/or Nahm equations.
Multi-point fibre optic hot-spot network integrated into a high power transformer
NASA Astrophysics Data System (ADS)
Lobo Ribeiro, A. B.; Eira, N.; Sousa, J. M.; Guerreiro, P. T.; Salcedo, J. A. R.
2007-07-01
A multi-point fibre optic temperature sensor network integrated inside a power transformer for continuous monitoring of hot-spots on windings, cellulose insulations and oil, is demonstrated and tested. The temperature sensors are based on proprietary encapsulated fibre Bragg grating (FBG) sensors and the optical interrogation unit uses a special designed narrowband high power broadband fibre source. The fibre optic sensing network is integrated into a 440 MVA power transformer having 12 temperature sensing points, distributed over several physical locations inside de transformer (windings, cellulose insulators, magnetic circuit and cooling oil entrance and exit).
Federal Register 2010, 2011, 2012, 2013, 2014
2011-03-28
... Transformation--Automated Integrated Operating Environment (IOE), New Information Collection; Comment Request... Operating Environment (IOE); OMB Control No. 1615-NEW. SUMMARY: USCIS is developing an automated Integrated Operating Environment (IOE) to process benefit applications. The IOE will collect information by asking...
Laplace transform approach for solving integral equations using computer algebra system
NASA Astrophysics Data System (ADS)
Paneva-Konovska, Jordanka; Nikolova, Yanka
2016-12-01
The Laplace transform method, along with Computer Algebra Systems (CAS) "Maple" v. 13, are extremely successfully applied for solving a class of integral equations with an arbitrary order, including fractional order integral equations. The combining of both powerful approaches allows students more quickly, enjoyable and thoroughly to master the material.
Transforming Academic Nursing: From Balance through Integration to Coherence.
ERIC Educational Resources Information Center
Langston, Nancy F.; Cowling, W. Richard, III; McCain, Nancy L.
1999-01-01
The academic mission should move from teaching-research-service to a holistic model with a single, integrative focus on knowledge work. The unity of knowledge development, dissemination, and application by a community of scholars promotes coherence at the university, unit, and scholar level. (SK)
Transforming Water Management: an Emerging Promise of Integrated Earth Observations
NASA Astrophysics Data System (ADS)
Lawford, R. G.
2011-12-01
Throughout its history, civilization has relied on technology to facilitate many of its advances. New innovations and technologies have often provided strategic advantages that have led to transformations in institutions, economies and ultimately societies. Observational and information technologies are leading to significant developments in the water sector. After a brief introduction tracing the role of observational technologies in the areas of hydrology and water cycle science, this talk explores the existing and potential contributions of remote sensing data in water resource management around the world. In particular, it outlines the steps being undertaken by the Group on Earth Observations (GEO) and its Water Task to facilitate capacity building efforts in water management using Earth Observations in Asia, Africa and Latin and Caribbean America. Success stories on the benefits of using Earth Observations and applying GEO principles are provided. While GEO and its capacity building efforts are contributing to the transformation of water management through interoperability, data sharing, and capacity building, the full potential of these contributions has not been fully realized because impediments and challenges still remain.
Pérez, Alejandro; von Lilienfeld, O Anatole
2011-08-09
Thermodynamic integration, perturbation theory, and λ-dynamics methods were applied to path integral molecular dynamics calculations to investigate free energy differences due to "alchemical" transformations. Several estimators were formulated to compute free energy differences in solvable model systems undergoing changes in mass and/or potential. Linear and nonlinear alchemical interpolations were used for the thermodynamic integration. We find improved convergence for the virial estimators, as well as for the thermodynamic integration over nonlinear interpolation paths. Numerical results for the perturbative treatment of changes in mass and electric field strength in model systems are presented. We used thermodynamic integration in ab initio path integral molecular dynamics to compute the quantum free energy difference of the isotope transformation in the Zundel cation. The performance of different free energy methods is discussed.
NASA Astrophysics Data System (ADS)
Krasilenko, Vladimir G.; Nikolsky, Alexander I.; Lazarev, Alexander A.; Lazareva, Maria V.
2008-03-01
In the paper the actuality of neurophysiologically motivated neuron arrays with flexibly programmable functions and operations with possibility to select required accuracy and type of nonlinear transformation and learning are shown. We consider neurons design and simulation results of multichannel spatio-time algebraic accumulation - integration of optical signals. Advantages for nonlinear transformation and summation - integration are shown. The offered circuits are simple and can have intellectual properties such as learning and adaptation. The integrator-neuron is based on CMOS current mirrors and comparators. The performance: consumable power - 100...500 μW, signal period- 0.1...1ms, input optical signals power - 0.2...20 μW time delays - less 1μs, the number of optical signals - 2...10, integration time - 10...100 of signal periods, accuracy or integration error - about 1%. Various modifications of the neuron-integrators with improved performance and for different applications are considered in the paper.
NASA Astrophysics Data System (ADS)
Cai, Huiying; Zhu, Feng; Hao, Yingming; Lu, Rongrong
2016-10-01
Shape Matching under Affine Transformation (SMAT) is an important issue in shape analysis. Most of the existing SMAT methods are sensitive to noise or complicated because they usually need to extract the edge points or compute the high order function of the shape. To solve these problems, a new SMAT method which combines the low order shape normalization and the multi-scale area integral features is proposed. First, the shapes with affine transformation are normalized into their orthogonal representations according to the moments and an equivalent resample. This procedure transforms the shape by several linear operations: translations, scaling, and rotation, following by a resample operation. Second, the Multi-Scale Area Integral Features (MSAIF) of the shapes which are invariant to the orthogonal transformation (rotation and reflection transformation) are extracted. The MSAIF is a signature achieved through concatenating the area integral feature at a range of scales from fine to coarse. The area integral feature is an integration of the feature values, which are computed by convoluting the shape with an isotropic kernel and taking the complement, over the shape domain following by the normalization using the area of the shape. Finally, the matching of different shapes is performed according to the dissimilarity which is measured with the optimal transport distance. The performance of the proposed method is tested on the car dataset and the multi-view curve dataset. Experimental results show that the proposed method is efficient and robust, and can be used in many shape analysis works.
Integrative Approach for a Transformative Freshman-Level STEM Curriculum
Curran, Kathleen L.; Olsen, Paul E.; Nwogbaga, Agashi P.; Stotts, Stephanie
2016-01-01
In 2014 Wesley College adopted a unified undergraduate program of evidence-based high-impact teaching practices. Through foundation and federal and state grant support, the college completely revised its academic core curriculum and strengthened its academic support structures by including a comprehensive early alert system for at-risk students. In this core, science, technology, engineering, and mathematics (STEM) faculty developed fresh manifestations of integrated concept-based introductory courses and revised upper-division STEM courses around student-centered learning. STEM majors can participate in specifically designed paid undergraduate research experiences in directed research elective courses. Such a college-wide multi-tiered approach results in institutional cultural change. PMID:27064213
Radiative capture versus Coulomb dissociation.
Esbensen, H.; Physics
2006-01-01
Measurements of the Coulomb dissociation of {sup 8}B have been used to infer the rate of the inverse radiative proton capture on {sup 7}Be. The analysis is usually based on the assumptions that the two processes are related by detailed balance and described by E1 transitions. However, there are corrections to this relation. The Coulomb form factors for the two processes, for example, are not identical. There are also E2 transitions and higher-order effects in the Coulomb dissociation, and the nuclear induced breakup cannot always be ignored. While adding first-order E2 transitions enhances the decay energy spectrum, the other mechanisms cause a suppression at low relative energies. The net result may accidentally be close to the conventional first-order E1 calculation, but there are differences which cannot be ignored if accuracies of 10% or better are needed.
NASA Astrophysics Data System (ADS)
Ji, Jia-Liang; Zhu, Zuo-Nong
2017-01-01
Very recently, Ablowitz and Musslimani introduced a new integrable nonlocal nonlinear Schrödinger equation. In this paper, we investigate an integrable nonlocal modified Korteweg-de Vries equation (mKdV) which can be derived from the well-known AKNS system. We construct the Darboux transformation for the nonlocal mKdV equation. Using the Darboux transformation, we obtain its different kinds of exact solutions including soliton, kink, antikink, complexiton, rogue-wave solution, and nonlocalized solution with singularities. It is shown that these solutions possess new properties which are different from the ones for mKdV equation.
Transformation of Mycoplasma gallisepticum with Tn916, Tn4001, and integrative plasmid vectors.
Cao, J.; Kapke, P. A.; Minion, F. C.
1994-01-01
Mycoplasma gallisepticum causes respiratory disease in avian species, but little is known about its mechanism(s) of pathogenesis. These studies were undertaken in order to develop genetic systems for analysis of potential virulence factors. M. gallisepticum was transformed with plasmids containing one of the gram-positive transposons Tn916 or Tn4001, which inserted randomly into the mycoplasmal chromosome. Plasmids containing cloned chromosomal DNA were also constructed and tested for integration into regions of DNA homology derived either from chromosomal fragments or from the gentamicin resistance marker from Tn4001. These studies demonstrate that M. gallisepticum is amenable to transformation with both transposons and integrative vectors. Images PMID:8021232
Stratified flow over a backward-facing step: hybrid solution by integral transforms
NASA Astrophysics Data System (ADS)
Ramos, R.; Perez Guerrero, J. S.; Cotta, R. M.
2001-01-01
The generalized integral transform technique (GITT) is employed in the hybrid numerical-analytical solution of the stratified backward-facing step flow problem, with automatic global accuracy control towards a user-prescribed accuracy target. The present paper is aimed at extending the available database on benchmark results in heat and fluid flow, which were progressively obtained through integral transforms, for the co-validation of more flexible fully discrete approaches. Numerical results are presented for the situations more frequently encountered in the literature Copyright
Coulomb interactions in particle beams
Jansen, G.H. )
1990-01-01
This book develops analytical and computer models for beams in which Coulomb interactions are important. The research into the different phenomena of Coulomb interactions in particle beams is stimulated by developments in the field of electron beam lithography for VLSI electronics. The standard theory of charged particle optics breaks down for intense beams in which interactions between particles are significant. This monograph is devoted to the theory of these intense beams, which are not only used in VLSI electronics but also in scanning electron microscopes. The theory is also applicable to focused ion beams, which are used in VLSI mask repair.
Room temperature Coulomb blockade mediated field emission via self-assembled gold nanoparticles
NASA Astrophysics Data System (ADS)
Wang, Fei; Fang, Jingyue; Chang, Shengli; Qin, Shiqiao; Zhang, Xueao; Xu, Hui
2017-02-01
Coulomb blockade mediated field-emission current was observed in single-electron tunneling devices based on self-assembled gold nanoparticles at 300 K. According to Raichev's theoretical model, by fixing a proper geometric distribution of source, island and drain, the transfer characteristics can be well explained through a combination of Coulomb blockade and field emission. Coulomb blockade and field emission alternately happen in our self-assembled devices. The Coulomb island size derived from the experimental data is in good agreement with the average size of the gold nanoparticles used in the device. The integrated tunneling can be adjusted via a gate electrode.
Helicity is the only integral invariant of volume-preserving transformations
Enciso, Alberto; Peralta-Salas, Daniel; de Lizaur, Francisco Torres
2016-01-01
We prove that any regular integral invariant of volume-preserving transformations is equivalent to the helicity. Specifically, given a functional ℐ defined on exact divergence-free vector fields of class C1 on a compact 3-manifold that is associated with a well-behaved integral kernel, we prove that ℐ is invariant under arbitrary volume-preserving diffeomorphisms if and only if it is a function of the helicity. PMID:26864201
Helicity is the only integral invariant of volume-preserving transformations.
Enciso, Alberto; Peralta-Salas, Daniel; de Lizaur, Francisco Torres
2016-02-23
We prove that any regular integral invariant of volume-preserving transformations is equivalent to the helicity. Specifically, given a functional I defined on exact divergence-free vector fields of class C(1) on a compact 3-manifold that is associated with a well-behaved integral kernel, we prove that I is invariant under arbitrary volume-preserving diffeomorphisms if and only if it is a function of the helicity.
A system for multi-locus chromosomal integration and transformation-free selection marker rescue
Siddiqui, Michael S.; Choksi, Atri; Smolke, Christina D.
2014-01-01
Yeast integrating plasmids (YIPs) are a versatile tool for stable integration in Saccharomyces cerevisiae. However, current YIP systems necessitate time- and labor-intensive methods for cloning and selection marker rescue. Here we describe the design, construction, and validation of a new YIP system capable of accelerating the stable integration of multiple expression constructs into different loci in the yeast S. cerevisiae. These “directed pop-out” plasmids enable a simple, two-step integration protocol that results in a scarless integration alongside a complete rescue of the selection marker. These plasmids combine three key features: a dedicated “YIPout” fragment directs a recombination event that rescues the selection marker while avoiding undesired excision of the target DNA sequence, a multi-fragment modular DNA assembly system simplifies cloning, and a new set of counterselectable markers enables serial integration followed by a transformation-free marker rescue event. We constructed and tested directed pop-out YIPs for integration of fluorescent reporter genes into four yeast loci. We validated our new YIP design by integrating three reporter genes into three different loci with transformation-free rescue of selection markers. These new YIP designs will facilitate the construction of yeast strains that express complex heterologous metabolic pathways. PMID:25226817
LACKS,S.A.
2003-10-09
Transformation, which alters the genetic makeup of an individual, is a concept that intrigues the human imagination. In Streptococcus pneumoniae such transformation was first demonstrated. Perhaps our fascination with genetics derived from our ancestors observing their own progeny, with its retention and assortment of parental traits, but such interest must have been accelerated after the dawn of agriculture. It was in pea plants that Gregor Mendel in the late 1800s examined inherited traits and found them to be determined by physical elements, or genes, passed from parents to progeny. In our day, the material basis of these genetic determinants was revealed to be DNA by the lowly bacteria, in particular, the pneumococcus. For this species, transformation by free DNA is a sexual process that enables cells to sport new combinations of genes and traits. Genetic transformation of the type found in S. pneumoniae occurs naturally in many species of bacteria (70), but, initially only a few other transformable species were found, namely, Haemophilus influenzae, Neisseria meningitides, Neisseria gonorrheae, and Bacillus subtilis (96). Natural transformation, which requires a set of genes evolved for the purpose, contrasts with artificial transformation, which is accomplished by shocking cells either electrically, as in electroporation, or by ionic and temperature shifts. Although such artificial treatments can introduce very small amounts of DNA into virtually any type of cell, the amounts introduced by natural transformation are a million-fold greater, and S. pneumoniae can take up as much as 10% of its cellular DNA content (40).
Integrated Environmental Modeling (IEM) systems that account for the fate/transport of organics frequently require physicochemical properties as well as transformation products. A myriad of chemical property databases exist but these can be difficult to access and often do not co...
ERIC Educational Resources Information Center
Wetzel, David R.
The purpose of this study was to determine the effects of an implementation plan that would support middle school science teachers as they integrated a specific technological tool, Calculator-Based Laboratory (CBL) probeware. The final goal of the implementation process was pedagogical and curricula transformation by the participants. The…
Integrated Environmental Modeling (IEM) systems that account for the fate/transport of organics frequently require physicochemical properties as well as transformation products. A myriad of chemical property databases exist but these can be difficult to access and often do not co...
Integrated Environmental Modeling (IEM) systems that account for the fate/transport of organics frequently require physicochemical properties as well as transformation products. A myriad of chemical property databases exist but these can be difficult to access and often do not co...
Integrated Environmental Modeling (IEM) systems that account for the fate/transport of organics frequently require physicochemical properties as well as transformation products. A myriad of chemical property databases exist but these can be difficult to access and often do not co...
Holographic CFTs on maximally symmetric spaces: Correlators, integral transforms, and applications
NASA Astrophysics Data System (ADS)
Hinterbichler, Kurt; Stokes, James; Trodden, Mark
2015-09-01
We study one- and two-point functions of conformal field theories (CFTs) on spaces of maximal symmetry with and without boundaries and investigate their spectral representations. Integral transforms are found, relating the spectral decomposition to renormalized position-space correlators. Several applications are presented, including the holographic boundary CFTs as well as spacelike boundary CFTs, which provide realizations of the pseudoconformal universe.
Darboux transformation of a semi-discrete coupled dispersionless integrable system
NASA Astrophysics Data System (ADS)
Riaz, H. Wajahat A.; ul Hassan, Mahmood
2017-07-01
We present Darboux transformation (DT) of a semi-discrete coupled dispersionless (SDCD) integrable system. A Lax pair for the SDCD system is proposed and a Darboux transformation is employed on the solutions to the Lax pair and solutions to the SDCD system. Multisoliton solutions resulting from Darboux transformation are expressed in terms of determinants. We also compute explicit expressions of one- and two-soliton solutions with the help of a given seed solution. We apply an appropriate continuum limit to obtain multisoliton solutions of the continuous CD integrable system. By taking an appropriate choice of discrete variables, we show that the SDCD system is equivalent to semi-discrete sine-Gordon equation. From the soliton solution of SDCD system, semi-discrete kink solution of the semi-discrete sine-Gordon equation is obtained.
Stable unitary integrators for the numerical implementation of continuous unitary transformations
NASA Astrophysics Data System (ADS)
Savitz, Samuel; Refael, Gil
2017-09-01
The technique of continuous unitary transformations has recently been used to provide physical insight into a diverse array of quantum mechanical systems. However, the question of how to best numerically implement the flow equations has received little attention. The most immediately apparent approach, using standard Runge-Kutta numerical integration algorithms, suffers from both severe inefficiency due to stiffness and the loss of unitarity. After reviewing the formalism of continuous unitary transformations and Wegner's original choice for the infinitesimal generator of the flow, we present a number of approaches to resolving these issues including a choice of generator which induces what we call the "uniform tangent decay flow" and three numerical integrators specifically designed to perform continuous unitary transformations efficiently while preserving the unitarity of flow. We conclude by applying one of the flow algorithms to a simple calculation that visually demonstrates the many-body localization transition.
Using the Screened Coulomb Potential to Illustrate the Variational Method
ERIC Educational Resources Information Center
Zuniga, Jose; Bastida, Adolfo; Requena, Alberto
2012-01-01
The screened Coulomb potential, or Yukawa potential, is used to illustrate the application of the single and linear variational methods. The trial variational functions are expressed in terms of Slater-type functions, for which the integrals needed to carry out the variational calculations are easily evaluated in closed form. The variational…
Using the Screened Coulomb Potential to Illustrate the Variational Method
ERIC Educational Resources Information Center
Zuniga, Jose; Bastida, Adolfo; Requena, Alberto
2012-01-01
The screened Coulomb potential, or Yukawa potential, is used to illustrate the application of the single and linear variational methods. The trial variational functions are expressed in terms of Slater-type functions, for which the integrals needed to carry out the variational calculations are easily evaluated in closed form. The variational…
Phillips, Andrew B; Merrill, Jacqueline A
2015-12-01
Healthcare is in a period significant transformational activity through the accelerated adoption of healthcare technologies, new reimbursement systems that emphasize shared savings and care coordination, and the common place use of mobile technologies by patients, providers, and others. The complexity of healthcare creates barriers to transformational activity and has the potential to inhibit the desired paths toward change envisioned by policymakers. Methods for understanding how change is occurring within this complex environment are important to the evaluation of delivery system reform and the role of technology in healthcare transformation. This study examines the use on an integrative review methodology to evaluate the healthcare literature for evidence of technology transformation in healthcare. The methodology integrates the evaluation of a broad set of literature with an established evaluative framework to develop a more complete understanding of a particular topic. We applied this methodology and the framework of punctuated equilibrium (PEq) to the analysis of the healthcare literature from 2004 to 2012 for evidence of technology transformation, a time during which technology was at the forefront of healthcare policy. The analysis demonstrated that the established PEq framework applied to the literature showed considerable potential for evaluating the progress of policies that encourage healthcare transformation. Significant inhibitors to change were identified through the integrative review and categorized into ten themes that describe the resistant structure of healthcare delivery: variations in the environment; market complexity; regulations; flawed risks and rewards; change theories; barriers; ethical considerations; competition and sustainability; environmental elements, and internal elements. We hypothesize that the resistant nature of the healthcare system described by this study creates barriers to the direct consumer involvement and engagement
A DNase encoded by integrated element CJIE1 inhibits natural transformation of Campylobacter jejuni.
Gaasbeek, Esther J; Wagenaar, Jaap A; Guilhabert, Magalie R; Wösten, Marc M S M; van Putten, Jos P M; van der Graaf-van Bloois, Linda; Parker, Craig T; van der Wal, Fimme J
2009-04-01
The species Campylobacter jejuni is considered naturally competent for DNA uptake and displays strong genetic diversity. Nevertheless, nonnaturally transformable strains and several relatively stable clonal lineages exist. In the present study, the molecular mechanism responsible for the nonnatural transformability of a subset of C. jejuni strains was investigated. Comparative genome hybridization indicated that C. jejuni Mu-like prophage integrated element 1 (CJIE1) was more abundant in nonnaturally transformable C. jejuni strains than in naturally transformable strains. Analysis of CJIE1 indicated the presence of dns (CJE0256), which is annotated as a gene encoding an extracellular DNase. DNase assays using a defined dns mutant and a dns-negative strain expressing Dns from a plasmid indicated that Dns is an endogenous DNase. The DNA-hydrolyzing activity directly correlated with the natural transformability of the knockout mutant and the dns-negative strain expressing Dns from a plasmid. Analysis of a broader set of strains indicated that the majority of nonnaturally transformable strains expressed DNase activity, while all naturally competent strains lacked this activity. The inhibition of natural transformation in C. jejuni via endogenous DNase activity may contribute to the formation of stable lineages in the C. jejuni population.
Coulomb interaction in multiple scattering theory
NASA Astrophysics Data System (ADS)
Ray, L.; Hoffmann, G. W.; Thaler, R. M.
1980-10-01
The treatment of the Coulomb interaction in the multiple scattering theories of Kerman-McManus-Thaler and Watson is examined in detail. By neglecting virtual Coulomb excitations, the lowest order Coulomb term in the Watson optical potential is shown to be a convolution of the point Coulomb interaction with the distributed nuclear charge, while the equivalent Kerman-McManus-Thaler Coulomb potential is obtained from an averaged, single-particle Coulombic T matrix. The Kerman-McManus-Thaler Coulomb potential is expressed as the Watson Coulomb term plus additional Coulomb-nuclear and Coulomb-Coulomb cross terms, and the omission of the extra terms in usual Kerman-McManus-Thaler applications leads to negative infinite total reaction cross section predictions and incorrect pure Coulomb scattering limits. Approximations are presented which eliminate these anomalies. Using the two-potential formula, the full projectile-nucleus T matrix is separated into two terms, one resulting from the distributed nuclear charge and the other being a Coulomb distorted nuclear T matrix. It is shown that the error resulting from the omission of the Kerman-McManus-Thaler Coulomb terms is effectively removed when the pure Coulomb T matrix in Kerman-McManus-Thaler is replaced by the analogous quantity in the Watson approach. Using the various approximations, theoretical angular distributions are obtained for 800 MeV p+208Pb elastic scattering and compared with experimental data. NUCLEAR REACTIONS 208Pb(p, p), E=0.8 GeV, Kerman, McManus, and Thaler, and Watson multiple scattering theories, Coulomb correction terms, high momentum transfer.
Carmen Legaz-García, María Del; Miñarro-Giménez, José Antonio; Menárguez-Tortosa, Marcos; Fernández-Breis, Jesualdo Tomás
2016-06-03
Biomedical research usually requires combining large volumes of data from multiple heterogeneous sources, which makes difficult the integrated exploitation of such data. The Semantic Web paradigm offers a natural technological space for data integration and exploitation by generating content readable by machines. Linked Open Data is a Semantic Web initiative that promotes the publication and sharing of data in machine readable semantic formats. We present an approach for the transformation and integration of heterogeneous biomedical data with the objective of generating open biomedical datasets in Semantic Web formats. The transformation of the data is based on the mappings between the entities of the data schema and the ontological infrastructure that provides the meaning to the content. Our approach permits different types of mappings and includes the possibility of defining complex transformation patterns. Once the mappings are defined, they can be automatically applied to datasets to generate logically consistent content and the mappings can be reused in further transformation processes. The results of our research are (1) a common transformation and integration process for heterogeneous biomedical data; (2) the application of Linked Open Data principles to generate interoperable, open, biomedical datasets; (3) a software tool, called SWIT, that implements the approach. In this paper we also describe how we have applied SWIT in different biomedical scenarios and some lessons learned. We have presented an approach that is able to generate open biomedical repositories in Semantic Web formats. SWIT is able to apply the Linked Open Data principles in the generation of the datasets, so allowing for linking their content to external repositories and creating linked open datasets. SWIT datasets may contain data from multiple sources and schemas, thus becoming integrated datasets.
Gauge Theories on the Coulomb Branch
NASA Astrophysics Data System (ADS)
Schwarz, John H.
We construct the world-volume action of a probe D3-brane in AdS5 × S5 with N units of flux. It has the field content, symmetries, and dualities of the U(1) factor of 𝒩 = 4 U(N + 1) super Yang-Mills theory, spontaneously broken to U(N) × U(1) by being on the Coulomb branch, with the massive fields integrated out. This motivates the conjecture that it is the exact effective action, called a highly effective action (HEA). We construct an SL(2, Z) multiplet of BPS soliton solutions of the D3-brane theory (the conjectured HEA) and show that they reproduce the electrically charged massive states that have been integrated out as well as magnetic monopoles and dyons. Their charges are uniformly spread on a spherical surface, called a soliton bubble, which is interpreted as a phase boundary.
Daskaloyannis, C. Tanoudis, Y.
2008-05-15
The two-dimensional quantum superintegrable systems with quadratic integrals of motion on a manifold are classified by using the quadratic associative algebra of the integrals of motion. There are six general fundamental classes of quantum superintegrable systems corresponding to the classical ones. Analytic formulas for the involved integrals are calculated in all the cases. All the known quantum superintegrable systems with quadratic integrals are classified as special cases of these six general classes. The coefficients of the quadratic associative algebra of integrals are calculated and they are compared to the coefficients of the corresponding coefficients of the Poisson quadratic algebra of the classical systems. The quantum coefficients are similar to the classical ones multiplied by a quantum coefficient -{h_bar}{sup 2} plus a quantum deformation of order {h_bar}{sup 4} and {h_bar}{sup 6}. The systems inside the classes are transformed using Staeckel transforms in the quantum case as in the classical case. The general form of the Staeckel transform between superintegrable systems is discussed.
Baker, W.R.
1959-08-25
Transformers of a type adapted for use with extreme high power vacuum tubes where current requirements may be of the order of 2,000 to 200,000 amperes are described. The transformer casing has the form of a re-entrant section being extended through an opening in one end of the cylinder to form a coaxial terminal arrangement. A toroidal multi-turn primary winding is disposed within the casing in coaxial relationship therein. In a second embodiment, means are provided for forming the casing as a multi-turn secondary. The transformer is characterized by minimized resistance heating, minimized external magnetic flux, and an economical construction.
1990-12-01
validate the Hilbert transform design prior to the incorporation into the WSI project. To facilitate the performance test, a Pin Grid Array (PGA) package ...thank the members of my committee for their comments and suggestions throughout the process. Since I knew very little about the design of circuitry...8 Summary ....... .................... ... 10 II. Equipment and Experimental Procedure .... ......... 11 IC Circuit Design
Coulomb and nuclear effects in breakup and reaction cross sections
NASA Astrophysics Data System (ADS)
Descouvemont, P.; Canto, L. F.; Hussein, M. S.
2017-01-01
We use a three-body continuum discretized coupled channel (CDCC) model to investigate Coulomb and nuclear effects in breakup and reaction cross sections. The breakup of the projectile is simulated by a finite number of square integrable wave functions. First we show that the scattering matrices can be split in a nuclear term and in a Coulomb term. This decomposition is based on the Lippmann-Schwinger equation and requires the scattering wave functions. We present two different methods to separate both effects. Then, we apply this separation to breakup and reaction cross sections of 7Li+208Pb . For breakup, we investigate various aspects, such as the role of the α +t continuum, the angular-momentum distribution, and the balance between Coulomb and nuclear effects. We show that there is a large ambiguity in defining the Coulomb and nuclear breakup cross sections, since both techniques, although providing the same total breakup cross sections, strongly differ for the individual components. We suggest a third method which could be efficiently used to address convergence problems at large angular momentum. For reaction cross sections, interference effects are smaller, and the nuclear contribution is dominant above the Coulomb barrier. We also draw attention to different definitions of the reaction cross section which exist in the literature and which may induce small, but significant, differences in the numerical values.
Nonstationary multistate Coulomb and multistate exponential models for nonadiabatic transitions
Ostrovsky, V. N.
2003-07-01
The nonstationary Schroedinger equation is considered in a finite basis of states. The model Hamiltonian matrix corresponds to a single diabatic potential curve with a Coulombic {approx}1/t time dependence. An arbitrary number of other diabatic potential curves are flat, i.e., time independent and have arbitrary energies. Related states are coupled by constant interactions with the Coulomb state. The resulting nonstationary Schroedinger equation is solved by the method of contour integral. Probabilities of transitions to any other state are obtained as t{yields}{infinity} in a simple analytical form for the case when the Coulomb state is populated initially (at instant of time t{yields}+0). The formulas apply both to the cases when a horizontal diabatic potential curve is crossed by the Coulomb one and to a noncrossing situation. In the limit of weak coupling, the transition probabilities are interpreted in terms of a sequence of pairwise Landau-Zener-type transitions. Mapping of the Coulomb model onto an exactly solvable exponential multistate model is established. For the special two-state case, the well-known Nikitin model is recovered.
Non-parametric transformation for data correlation and integration: From theory to practice
Datta-Gupta, A.; Xue, Guoping; Lee, Sang Heon
1997-08-01
The purpose of this paper is two-fold. First, we introduce the use of non-parametric transformations for correlating petrophysical data during reservoir characterization. Such transformations are completely data driven and do not require a priori functional relationship between response and predictor variables which is the case with traditional multiple regression. The transformations are very general, computationally efficient and can easily handle mixed data types for example, continuous variables such as porosity, permeability and categorical variables such as rock type, lithofacies. The power of the non-parametric transformation techniques for data correlation has been illustrated through synthetic and field examples. Second, we utilize these transformations to propose a two-stage approach for data integration during heterogeneity characterization. The principal advantages of our approach over traditional cokriging or cosimulation methods are: (1) it does not require a linear relationship between primary and secondary data, (2) it exploits the secondary information to its fullest potential by maximizing the correlation between the primary and secondary data, (3) it can be easily applied to cases where several types of secondary or soft data are involved, and (4) it significantly reduces variance function calculations and thus, greatly facilitates non-Gaussian cosimulation. We demonstrate the data integration procedure using synthetic and field examples. The field example involves estimation of pore-footage distribution using well data and multiple seismic attributes.
Brenna, Andrea; Montanini, Barbara; Muggiano, Eleonora; Proietto, Marco; Filetici, Patrizia; Ottonello, Simone; Ballario, Paola
2014-01-01
Agrobacterium tumefaciens-mediated transformation is a powerful tool for reverse genetics and functional genomic analysis in a wide variety of plants and fungi. Tuber spp. are ecologically important and gastronomically prized fungi ("truffles") with a cryptic life cycle, a subterranean habitat and a symbiotic, but also facultative saprophytic lifestyle. The genome of a representative member of this group of fungi has recently been sequenced. However, because of their poor genetic tractability, including transformation, truffles have so far eluded in-depth functional genomic investigations. Here we report that A. tumefaciens can infect Tuber borchii mycelia, thereby conveying its transfer DNA with the production of stably integrated transformants. We constructed two new binary plasmids (pABr1 and pABr3) and tested them as improved transformation vectors using the green fluorescent protein as reporter gene and hygromycin phosphotransferase as selection marker. Transformants were stable for at least 12 months of in vitro culture propagation and, as revealed by TAIL- PCR analysis, integration sites appear to be heterogeneous, with a preference for repeat element-containing genome sites.
Numerical implementation of the integral-transform solution to Lamb's point-load problem
NASA Astrophysics Data System (ADS)
Georgiadis, H. G.; Vamvatsikos, D.; Vardoulakis, I.
The present work describes a procedure for the numerical evaluation of the classical integral-transform solution of the transient elastodynamic point-load (axisymmetric) Lamb's problem. This solution involves integrals of rapidly oscillatory functions over semi-infinite intervals and inversion of one-sided (time) Laplace transforms. These features introduce difficulties for a numerical treatment and constitute a challenging problem in trying to obtain results for quantities (e.g. displacements) in the interior of the half-space. To deal with the oscillatory integrands, which in addition may take very large values (pseudo-pole behavior) at certain points, we follow the concept of Longman's method but using as accelerator in the summation procedure a modified Epsilon algorithm instead of the standard Euler's transformation. Also, an adaptive procedure using the Gauss 32-point rule is introduced to integrate in the vicinity of the pseudo-pole. The numerical Laplace-transform inversion is based on the robust Fourier-series technique of Dubner/Abate-Crump-Durbin. Extensive results are given for sub-surface displacements, whereas the limit-case results for the surface displacements compare very favorably with previous exact results.
A transformed path integral approach for solution of the Fokker-Planck equation
NASA Astrophysics Data System (ADS)
Subramaniam, Gnana M.; Vedula, Prakash
2017-10-01
A novel path integral (PI) based method for solution of the Fokker-Planck equation is presented. The proposed method, termed the transformed path integral (TPI) method, utilizes a new formulation for the underlying short-time propagator to perform the evolution of the probability density function (PDF) in a transformed computational domain where a more accurate representation of the PDF can be ensured. The new formulation, based on a dynamic transformation of the original state space with the statistics of the PDF as parameters, preserves the non-negativity of the PDF and incorporates short-time properties of the underlying stochastic process. New update equations for the state PDF in a transformed space and the parameters of the transformation (including mean and covariance) that better accommodate nonlinearities in drift and non-Gaussian behavior in distributions are proposed (based on properties of the SDE). Owing to the choice of transformation considered, the proposed method maps a fixed grid in transformed space to a dynamically adaptive grid in the original state space. The TPI method, in contrast to conventional methods such as Monte Carlo simulations and fixed grid approaches, is able to better represent the distributions (especially the tail information) and better address challenges in processes with large diffusion, large drift and large concentration of PDF. Additionally, in the proposed TPI method, error bounds on the probability in the computational domain can be obtained using the Chebyshev's inequality. The benefits of the TPI method over conventional methods are illustrated through simulations of linear and nonlinear drift processes in one-dimensional and multidimensional state spaces. The effects of spatial and temporal grid resolutions as well as that of the diffusion coefficient on the error in the PDF are also characterized.
Ontology for Transforming Geo-Spatial Data for Discovery and Integration of Scientific Data
NASA Astrophysics Data System (ADS)
Nguyen, L.; Chee, T.; Minnis, P.
2013-12-01
Discovery and access to geo-spatial scientific data across heterogeneous repositories and multi-discipline datasets can present challenges for scientist. We propose to build a workflow for transforming geo-spatial datasets into semantic environment by using relationships to describe the resource using OWL Web Ontology, RDF, and a proposed geo-spatial vocabulary. We will present methods for transforming traditional scientific dataset, use of a semantic repository, and querying using SPARQL to integrate and access datasets. This unique repository will enable discovery of scientific data by geospatial bound or other criteria.
Coulomb dissociation of N,2120
NASA Astrophysics Data System (ADS)
Röder, Marko; Adachi, Tatsuya; Aksyutina, Yulia; Alcantara, Juan; Altstadt, Sebastian; Alvarez-Pol, Hector; Ashwood, Nicholas; Atar, Leyla; Aumann, Thomas; Avdeichikov, Vladimir; Barr, M.; Beceiro, Saul; Bemmerer, Daniel; Benlliure, Jose; Bertulani, Carlos; Boretzky, Konstanze; Borge, Maria J. G.; Burgunder, G.; Caamaño, Manuel; Caesar, Christoph; Casarejos, Enrique; Catford, Wilton; Cederkäll, Joakim; Chakraborty, S.; Chartier, Marielle; Chulkov, Leonid; Cortina-Gil, Dolores; Crespo, Raquel; Datta Pramanik, Ushasi; Diaz-Fernandez, Paloma; Dillmann, Iris; Elekes, Zoltan; Enders, Joachim; Ershova, Olga; Estrade, A.; Farinon, F.; Fraile, Luis M.; Freer, Martin; Freudenberger, M.; Fynbo, Hans; Galaviz, Daniel; Geissel, Hans; Gernhäuser, Roman; Göbel, Kathrin; Golubev, Pavel; Gonzalez Diaz, D.; Hagdahl, Julius; Heftrich, Tanja; Heil, Michael; Heine, Marcel; Heinz, Andreas; Henriques, Ana; Holl, Matthias; Ickert, G.; Ignatov, Alexander; Jakobsson, Bo; Johansson, Hâkan; Jonson, Björn; Kalantar-Nayestanaki, Nasser; Kanungo, Rituparna; Kelic-Heil, Aleksandra; Knöbel, Ronja; Kröll, Thorsten; Krücken, Reiner; Kurcewicz, J.; Kurz, Nikolaus; Labiche, Marc; Langer, Christoph; Le Bleis, Tudi; Lemmon, Roy; Lepyoshkina, Olga; Lindberg, Simon; Machado, Jorge; Marganiec, Justyna; Mostazo Caro, Magdalena; Movsesyan, Alina; Najafi, Mohammad Ali; Nilsson, Thomas; Nociforo, Chiara; Panin, Valerii; Paschalis, Stefanos; Perea, Angel; Petri, Marina; Pietri, S.; Plag, Ralf; Prochazka, A.; Rahaman, Md. Anisur; Rastrepina, Ganna; Reifarth, Rene; Ribeiro, Guillermo; Ricciardi, M. Valentina; Rigollet, Catherine; Riisager, Karsten; Rossi, Dominic; Sanchez del Rio Saez, Jose; Savran, Deniz; Scheit, Heiko; Simon, Haik; Sorlin, Olivier; Stoica, V.; Streicher, Branislav; Taylor, Jon; Tengblad, Olof; Terashima, Satoru; Thies, Ronja; Togano, Yasuhiro; Uberseder, Ethan; Van de Walle, J.; Velho, Paulo; Volkov, Vasily; Wagner, Andreas; Wamers, Felix; Weick, Helmut; Weigand, Mario; Wheldon, Carl; Wilson, G.; Wimmer, Christine; Winfield, J. S.; Woods, Philip; Yakorev, Dmitry; Zhukov, Mikhail; Zilges, Andreas; Zuber, Kai; R3B Collaboration
2016-06-01
Neutron-rich light nuclei and their reactions play an important role in the creation of chemical elements. Here, data from a Coulomb dissociation experiment on N,2120 are reported. Relativistic N,2120 ions impinged on a lead target and the Coulomb dissociation cross section was determined in a kinematically complete experiment. Using the detailed balance theorem, the 19N (n ,γ )20N and 20N (n ,γ ) 21N excitation functions and thermonuclear reaction rates have been determined. The 19 (n ,γ )20N rate is up to a factor of 5 higher at T <1 GK with respect to previous theoretical calculations, leading to a 10% decrease in the predicted fluorine abundance.
Transformation as a Design Process and Runtime Architecture for High Integrity Software
Bespalko, S.J.; Winter, V.L.
1999-04-05
We have discussed two aspects of creating high integrity software that greatly benefit from the availability of transformation technology, which in this case is manifest by the requirement for a sophisticated backtracking parser. First, because of the potential for correctly manipulating programs via small changes, an automated non-procedural transformation system can be a valuable tool for constructing high assurance software. Second, modeling the processing of translating data into information as a, perhaps, context-dependent grammar leads to an efficient, compact implementation. From a practical perspective, the transformation process should begin in the domain language in which a problem is initially expressed. Thus in order for a transformation system to be practical it must be flexible with respect to domain-specific languages. We have argued that transformation applied to specification results in a highly reliable system. We also attempted to briefly demonstrate that transformation technology applied to the runtime environment will result in a safe and secure system. We thus believe that the sophisticated multi-lookahead backtracking parsing technology is central to the task of being in a position to demonstrate the existence of HIS.
Integration efficiencies of spontaneous mutant alleles of amiA locus in pneumococcal transformation.
Tiraby, G; Sicard, M A
1973-12-01
The distribution of integration efficiencies of independent mutations spontaneously occurring in the amiA locus was determined in two strains of pneumococcus. Strain Cl(3) integrates genetic markers with different efficiencies during transformation, whereas strain 401, isogenic with strain Cl(3), does not discriminate between markers and integrates all markers with the same high efficiency. The discriminating strain Cl(3) gives rise to spontaneous mutations in the locus amiA, which fall into four classes with respect to their individual integration efficiencies. Mutations with a low efficiency of integration are equal in number to mutations with a high efficiency. Mutations from the two other classes corresponding to intermediate and very high efficiencies are about five times less frequent. The same four classes were also found among amiA mutants spontaneously occurring in strain 401. However, the two distributions of integration efficiencies of amiA mutants arisen either in strain Cl(3) or strain 401 are significantly different. The number of spontaneous amiA mutants, estimated by two methods, was found to be higher in strain 401 than in strain Cl(3). The increase of the mutation rate in strain 401 could be accounted for by the excess of mutations falling in the two less-efficient classes observed in this strain. The discriminating process which acts during transformation presumably also intervenes in the appearance of spontaneous mutations.
NASA Astrophysics Data System (ADS)
Elliott, David; Johnston, Peter R.
2007-06-01
In the two-dimensional boundary element method, one often needs to evaluate numerically integrals of the form where j2 is a quadratic, g is a polynomial and f is a rational, logarithmic or algebraic function with a singularity at zero. The constants a and b are such that -1[less-than-or-equals, slant]a[less-than-or-equals, slant]1 and 0integration. In this case the direct application of Gauss-Legendre quadrature can give large truncation errors. By making the transformation x=a+bsinh([mu]u-[eta]), where the constants [mu] and [eta] are chosen so that the interval of integration is again [-1,1], it is found that the truncation errors arising, when the same Gauss-Legendre quadrature is applied to the transformed integral, are much reduced. The asymptotic error analysis for Gauss-Legendre quadrature, as given by Donaldson and Elliott [A unified approach to quadrature rules with asymptotic estimates of their remainders, SIAM J. Numer. Anal. 9 (1972) 573-602], is then used to explain this phenomenon and justify the transformation.
Supporting the transformative process: experiences of cancer patients receiving integrative care.
Mulkins, Andrea L; Verhoef, Marja J
2004-09-01
The purpose of this study is to describe the essential features of the transformative experience among people living with cancer who are seeking integrative care and to identify factors supporting this process. It is hoped that after establishing the nature and meaning of this change or shift, one will better understand what is most meaningful in terms of providing appropriate care and support to patients seeking integrative care. An interpretational, qualitative approach guided sampling, data collection, and analysis with 11 individuals. A purposeful sample was drawn from selected integrative care facilities according to sociodemographics and type of cancer. Due to the complexity of this subject, second interviews were conducted with 5 participants to enhance the richness and validity of the data. The experience of transformation is a dynamic 4-stage process in which participants learned about themselves and became more aware of who they are and how they relate to the world. Participants found that 4 dimensions of integrative medicine played a fundamental role in supporting this process. These dimensions include (1) having access to a range of appropriate therapies to support individual journeys, (2) care that focuses on one's overall well-being, (3) control over cancer management, and (4) developing healing relationships with care providers. Although practitioners may not be able to create transformative experiences for patients, they may be able to establish and maintain conditions that support this process.
Integrated Personal Health Records: Transformative Tools for Consumer-Centric Care
Detmer, Don; Bloomrosen, Meryl; Raymond, Brian; Tang, Paul
2008-01-01
Background Integrated personal health records (PHRs) offer significant potential to stimulate transformational changes in health care delivery and self-care by patients. In 2006, an invitational roundtable sponsored by Kaiser Permanente Institute, the American Medical Informatics Association, and the Agency for Healthcare Research and Quality was held to identify the transformative potential of PHRs, as well as barriers to realizing this potential and a framework for action to move them closer to the health care mainstream. This paper highlights and builds on the insights shared during the roundtable. Discussion While there is a spectrum of dominant PHR models, (standalone, tethered, integrated), the authors state that only the integrated model has true transformative potential to strengthen consumers' ability to manage their own health care. Integrated PHRs improve the quality, completeness, depth, and accessibility of health information provided by patients; enable facile communication between patients and providers; provide access to health knowledge for patients; ensure portability of medical records and other personal health information; and incorporate auto-population of content. Numerous factors impede widespread adoption of integrated PHRs: obstacles in the health care system/culture; issues of consumer confidence and trust; lack of technical standards for interoperability; lack of HIT infrastructure; the digital divide; uncertain value realization/ROI; and uncertain market demand. Recent efforts have led to progress on standards for integrated PHRs, and government agencies and private companies are offering different models to consumers, but substantial obstacles remain to be addressed. Immediate steps to advance integrated PHRs should include sharing existing knowledge and expanding knowledge about them, building on existing efforts, and continuing dialogue among public and private sector stakeholders. Summary Integrated PHRs promote active, ongoing
Coulomb blockade in graphene nanoribbons.
Sols, F; Guinea, F; Neto, A H
2007-10-19
We propose that recent transport experiments revealing the existence of an energy gap in graphene nanoribbons may be understood in terms of Coulomb blockade. Electron interactions play a decisive role at the quantum dots which form due to the presence of necks arising from the roughness of the graphene edge. With the average transmission as the only fitting parameter, our theory shows good agreement with the experimental data.
Ordering in classical Coulombic systems.
Schiffer, J. P.
1998-01-22
The author discusses the properties of classical Coulombic matter at low temperatures. It has been well known for some time [1,2] that infinite Coulombic matter will crystallize in body-centered cubic form when the quantity {Lambda} (the dimensionless ratio of the average two-particle Coulomb energy to the kinetic energy per particle) is larger than {approximately}175. But the systems of such particles that have been produced in the laboratory in ion traps, or ion beams, are finite with surfaces defined by the boundary conditions that have to be satisfied. This results in ion clouds with sharply defined curved surfaces, and interior structures that show up as a set of concentric layers that are parallel to the outer surface. The ordering does not appear to be cubic, but the charges on each shell exhibit a ''hexatic'' pattern of equilateral triangles that is the characteristic of liquid crystals. The curvature of the surfaces prevents the structures on successive shells from interlocking in any simple fashion. This class of structures was first found in simulations [3] and later in experiments [4].
Kiyokura, Takanori; Ito, Takahiro; Sawada, Renshi
2004-12-01
This paper describes a Fourier transform (FT) near-infrared spectrometer that uses an integrated prism scanning interferometer whose optical paths are stabilized by corner cubes. A combination of corner cubes and a retroreflection mirror, which is sometimes used in the conventional interferometer for FT spectrometers, is adopted and adapted to the integrated prism scanning interferometer through a special design. Without any degradation of spectroscopic properties, the optical path in the interferometer is highly stabilized and the moving distance of the stage is halved. These advantages provide a robust and portable FT spectrometer for field use.
Zhao, Guoliang; Sun, Kaibiao; Li, Hongxing
2013-01-01
This paper proposes new methodologies for the design of adaptive integral-sliding mode control. A tensor product model transformation based adaptive integral-sliding mode control law with respect to uncertainties and perturbations is studied, while upper bounds on the perturbations and uncertainties are assumed to be unknown. The advantage of proposed controllers consists in having a dynamical adaptive control gain to establish a sliding mode right at the beginning of the process. Gain dynamics ensure a reasonable adaptive gain with respect to the uncertainties. Finally, efficacy of the proposed controller is verified by simulations on an uncertain nonlinear system model.
Zhao, Guoliang; Li, Hongxing
2013-01-01
This paper proposes new methodologies for the design of adaptive integral-sliding mode control. A tensor product model transformation based adaptive integral-sliding mode control law with respect to uncertainties and perturbations is studied, while upper bounds on the perturbations and uncertainties are assumed to be unknown. The advantage of proposed controllers consists in having a dynamical adaptive control gain to establish a sliding mode right at the beginning of the process. Gain dynamics ensure a reasonable adaptive gain with respect to the uncertainties. Finally, efficacy of the proposed controller is verified by simulations on an uncertain nonlinear system model. PMID:24453897
NASA Astrophysics Data System (ADS)
Shen, Fabin; Wang, Anbo
2006-02-01
The numerical calculation of the Rayleigh-Sommerfeld diffraction integral is investigated. The implementation of a fast-Fourier-transform (FFT) based direct integration (FFT-DI) method is presented, and Simpson's rule is used to improve the calculation accuracy. The sampling interval, the size of the computation window, and their influence on numerical accuracy and on computational complexity are discussed for the FFT-DI and the FFT-based angular spectrum (FFT-AS) methods. The performance of the FFT-DI method is verified by numerical simulation and compared with that of the FFT-AS method.
Local-instantaneous filtering in the integral transform solution of nonlinear diffusion problems
NASA Astrophysics Data System (ADS)
Macêdo, E. N.; Cotta, R. M.; Orlande, H. R. B.
A novel filtering strategy is proposed to be utilized in conjunction with the Generalized Integral Transform Technique (GITT), in the solution of nonlinear diffusion problems. The aim is to optimize convergence enhancement, yielding computationally efficient eigenfunction expansions. The proposed filters include space and time dependence, extracted from linearized versions of the original partial differential system. The scheme automatically updates the filter along the time integration march, as the required truncation orders for the user requested accuracy begin to exceed a prescribed maximum system size. A fully nonlinear heat conduction example is selected to illustrate the computational performance of the filtering strategy, against the classical single-filter solution behavior.
ERIC Educational Resources Information Center
Grimm, C. A.
This document contains two units that examine integral transforms and series expansions. In the first module, the user is expected to learn how to use the unified method presented to obtain Laplace transforms, Fourier transforms, complex Fourier series, real Fourier series, and half-range sine series for given piecewise continuous functions. In…
Takatsuka, K
2001-07-01
We present an algebra that facilitates a systematic coordinate transformation in semiclassical integrals such as those between the initial and final value representations. Applying this algebra to Maslov-type semiclassical wave packet theory [A. Inoue-Ushiyama and K. Takatsuka, Phys. Rev. A 59, 3256 (1999)], a semiclassical correlation function is extracted, which is free of the amplitude factor that suffers an exponential divergence in a chaotic system.
Multisensory Integration Uses a Real-Time Unisensory-Multisensory Transform.
Miller, Ryan L; Stein, Barry E; Rowland, Benjamin A
2017-05-17
The manner in which the brain integrates different sensory inputs to facilitate perception and behavior has been the subject of numerous speculations. By examining multisensory neurons in cat superior colliculus, the present study demonstrated that two operational principles are sufficient to understand how this remarkable result is achieved: (1) unisensory signals are integrated continuously and in real time as soon as they arrive at their common target neuron and (2) the resultant multisensory computation is modified in shape and timing by a delayed, calibrating inhibition. These principles were tested for descriptive sufficiency by embedding them in a neurocomputational model and using it to predict a neuron's moment-by-moment multisensory response given only knowledge of its responses to the individual modality-specific component cues. The predictions proved to be highly accurate, reliable, and unbiased and were, in most cases, not statistically distinguishable from the neuron's actual instantaneous multisensory response at any phase throughout its entire duration. The model was also able to explain why different multisensory products are often observed in different neurons at different time points, as well as the higher-order properties of multisensory integration, such as the dependency of multisensory products on the temporal alignment of crossmodal cues. These observations not only reveal this fundamental integrative operation, but also identify quantitatively the multisensory transform used by each neuron. As a result, they provide a means of comparing the integrative profiles among neurons and evaluating how they are affected by changes in intrinsic or extrinsic factors.SIGNIFICANCE STATEMENT Multisensory integration is the process by which the brain combines information from multiple sensory sources (e.g., vision and audition) to maximize an organism's ability to identify and respond to environmental stimuli. The actual transformative process by which
PREFACE: Strongly Coupled Coulomb Systems Strongly Coupled Coulomb Systems
NASA Astrophysics Data System (ADS)
Neilson, David; Senatore, Gaetano
2009-05-01
This special issue contains papers presented at the International Conference on Strongly Coupled Coulomb Systems (SCCS), held from 29 July-2 August 2008 at the University of Camerino. Camerino is an ancient hill-top town located in the Apennine mountains of Italy, 200 kilometres northeast of Rome, with a university dating back to 1336. The Camerino conference was the 11th in a series which started in 1977: 1977: Orleans-la-Source, France, as a NATO Advanced Study Institute on Strongly Coupled Plasmas (hosted by Marc Feix and Gabor J Kalman) 1982: Les Houches, France (hosted by Marc Baus and Jean-Pierre Hansen) 1986: Santa Cruz, California, USA (hosted by Forrest J Rogers and Hugh E DeWitt) 1989: Tokyo, Japan (hosted by Setsuo Ichimaru) 1992: Rochester, New York, USA (hosted by Hugh M Van Horn and Setsuo Ichimaru) 1995: Binz, Germany (hosted by Wolf Dietrich Kraeft and Manfred Schlanges) 1997: Boston, Massachusetts, USA (hosted by Gabor J Kalman) 1999: St Malo, France (hosted by Claude Deutsch and Bernard Jancovici) 2002: Santa Fe, New Mexico, USA (hosted by John F Benage and Michael S Murillo) 2005: Moscow, Russia (hosted by Vladimir E Fortov and Vladimir Vorob'ev). The name of the series was changed in 1996 from Strongly Coupled Plasmas to Strongly Coupled Coulomb Systems to reflect a wider range of topics. 'Strongly Coupled Coulomb Systems' encompasses diverse many-body systems and physical conditions. The purpose of the conferences is to provide a regular international forum for the presentation and discussion of research achievements and ideas relating to a variety of plasma, liquid and condensed matter systems that are dominated by strong Coulomb interactions between their constituents. Each meeting has seen an evolution of topics and emphases that have followed new discoveries and new techniques. The field has continued to see new experimental tools and access to new strongly coupled conditions, most recently in the areas of warm matter, dusty plasmas
Judelson, H S; Coffey, M D; Arredondo, F R; Tyler, B M
1993-03-01
A procedure for stable transformation was developed for Phytophthora megasperma f. sp. glycinea, an oomycete pathogen of soybean. Transformants were obtained using a bacterial hygromycin resistance gene fused to a promoter and terminator from the ham34 gene of another oomycete, Bremia lactucae. Vector DNA, alone or complexed to cationic liposomes, was introduced into protoplasts using polyethylene glycol and CaCl2. DNA and RNA hybridization, and phosphotransferase assays, confirmed the presence and expression of vector DNA in the transformants. Hybridization to electrophoretically separated chromosomes of P. m. glycinea showed that vector DNA had integrated into only one chromosome in four transformants, and into multiple chromosomes in one transformant.
Efficient local statistical analysis via integral histograms with discrete wavelet transform.
Lee, Teng-Yok; Shen, Han-Wei
2013-12-01
Histograms computed from local regions are commonly used in many visualization applications, and allowing the user to query histograms interactively in regions of arbitrary locations and sizes plays an important role in feature identification and tracking. Computing histograms in regions with arbitrary location and size, nevertheless, can be time consuming for large data sets since it involves expensive I/O and scan of data elements. To achieve both performance- and storage-efficient query of local histograms, we present a new algorithm called WaveletSAT, which utilizes integral histograms, an extension of the summed area tables (SAT), and discrete wavelet transform (DWT). Similar to SAT, an integral histogram is the histogram computed from the area between each grid point and the grid origin, which can be be pre-computed to support fast query. Nevertheless, because one histogram contains multiple bins, it will be very expensive to store one integral histogram at each grid point. To reduce the storage cost for large integral histograms, WaveletSAT treats the integral histograms of all grid points as multiple SATs, each of which can be converted into a sparse representation via DWT, allowing the reconstruction of axis-aligned region histograms of arbitrary sizes from a limited number of wavelet coefficients. Besides, we present an efficient wavelet transform algorithm for SATs that can operate on each grid point separately in logarithmic time complexity, which can be extended to parallel GPU-based implementation. With theoretical and empirical demonstration, we show that WaveletSAT can achieve fast preprocessing and smaller storage overhead than the conventional integral histogram approach with close query performance.
Elastic Coulomb breakup of 34Na
NASA Astrophysics Data System (ADS)
Singh, G.; Shubhchintak, Chatterjee, R.
2016-08-01
Background: 34Na is conjectured to play an important role in the production of seed nuclei in the alternate r -process paths involving light neutron rich nuclei very near the β -stability line, and as such, it is important to know its ground state properties and structure to calculate rates of the reactions it might be involved in, in the stellar plasma. Found in the region of `island of inversion', its ground state might not be in agreement with normal shell model predictions. Purpose: The aim of this paper is to study the elastic Coulomb breakup of 34Na on 208Pb to give us a core of 33Na with a neutron and in the process we try and investigate the one neutron separation energy and the ground state configuration of 34Na. Method: A fully quantum mechanical Coulomb breakup theory within the architecture of post-form finite range distorted wave Born approximation extended to include the effects of deformation is used to research the elastic Coulomb breakup of 34Na on 208Pb at 100 MeV/u. The triple differential cross section calculated for the breakup is integrated over the desired components to find the total cross-section, momentum, and angular distributions as well as the average momenta, along with the energy-angular distributions. Results: The total one neutron removal cross section is calculated to test the possible ground state configurations of 34Na. The average momentum results along with energy-angular calculations indicate 34Na to have a halo structure. The parallel momentum distributions with narrow full widths at half-maxima signify the same. Conclusion: We have attempted to analyze the possible ground state configurations of 34Na and in congruity with the patterns in the `island of inversion' conclude that even without deformation, 34Na should be a neutron halo with a predominant contribution to its ground state most probably coming from 33Na(3 /2+)⊗ 2 p3 /2ν configuration. We also surmise that it would certainly be useful and rewarding to test our
Longpré, Caroline; Dubois, Carl-Ardy
2015-03-03
Even though nurses are expected to play a key role in implementing integrated services networks, up to now their practice in this regard has received very little research attention. The aim of this study is to describe the extent to which the evolution of nursing practice in Quebec in recent years has converged with the requirements and efforts involved in services integration. This descriptive study was carried out with 107 nurses working an integrated network of healthcare services in Quebec in four different care pathways: chronic obstructive pulmonary disease, autonomy support for the elderly, palliative oncology care, and mental health. Development model for integrated care (DMIC) was used, first, to examine the prevalence in each pathway of integrative activities, grouped into nine practice dimensions, and then to position each pathway in relation to the four phases of development for any integration process, as defined by the DMIC. Only one pathway had reached Phase 3, which involves expansion and monitoring of integration, whereas the others were still in the preliminary Phases 1 and 2 characterized by initiative and experimentation. Only two dimensions out of nine ('quality of care' and 'interprofessional teamwork') were prevalent in all the pathways; two others ('transparent entrepreneurship' and 'performance management') were in none of the pathways, and the remaining five ('patient-family centered care', 'result-focused learning', 'delivery system', 'commitment', 'roles and tasks') were present to varying degrees. These results suggest that particular efforts should be made to bridge the significant gap between the pace of nursing practice transformation and the objectives of service integration. These efforts should focus, among other things, on the deployment of organizational, clinical, human, and material resources to support practice renewal and continuing education for nurses to prepare them for the requirements of integration.
van Peer, Arend F.; de Bekker, Charissa; Vinck, Arman; Wösten, Han A. B.; Lugones, Luis G.
2009-01-01
Phleomycin is mutagenic by introducing double-strand breaks in DNA. The ble gene of Streptoalloteychus hindustanus, which confers resistance to this substance, is widely used as a selection marker for transformation. Schizophyllum commune grows on 25 μg of phleomycin ml−1 after introduction of a resistance cassette based on the ble gene. However, we here report that growth of resistant colonies on this concentration of phleomycin resulted in aberrant colony morphologies. Apparently, phleomycin was mutagenic despite acquired resistance. Therefore, a new selection system was developed based on resistance to the antibiotic nourseothricin. However, the transformation efficiency was tenfold lower than that obtained with phleomycin as a selection agent. This low transformation efficiency could be rescued by addition of a nonselective concentration of phleomycin during protoplast regeneration. This was accompanied by a higher incidence of single-copy integrations and with an increase of expression of key genes involved in double-strand break repair. Taken together, we conclude that the effect of a nonselective concentration of phleomycin strongly resembles the effect of restriction enzyme-mediated integration (REMI) but, unlike REMI, it does not depend on the presence of a target restriction site. PMID:19114524
Newman, S. M.; Boynton, J. E.; Gillham, N. W.; Randolph-Anderson, B. L.; Johnson, A. M.; Harris, E. H.
1990-01-01
Transformation of chloroplast ribosomal RNA (rRNA) genes in Chlamydomonas has been achieved by the biolistic process using cloned chloroplast DNA fragments carrying mutations that confer antibiotic resistance. The sites of exchange employed during the integration of the donor DNA into the recipient genome have been localized using a combination of antibiotic resistance mutations in the 16S and 23S rRNA genes and restriction fragment length polymorphisms that flank these genes. Complete or nearly complete replacement of a region of the chloroplast genome in the recipient cell by the corresponding sequence from the donor plasmid was the most common integration event. Exchange events between the homologous donor and recipient sequences occurred preferentially near the vector:insert junctions. Insertion of the donor rRNA genes and flanking sequences into one inverted repeat of the recipient genome was followed by intramolecular copy correction so that both copies of the inverted repeat acquired identical sequences. Increased frequencies of rRNA gene transformants were achieved by reducing the copy number of the chloroplast genome in the recipient cells and by decreasing the heterology between donor and recipient DNA sequences flanking the selectable markers. In addition to producing bona fide chloroplast rRNA transformants, the biolistic process induced mutants resistant to low levels of streptomycin, typical of nuclear mutations in Chlamydomonas. PMID:1981764
Coulomb crystallization in two-component quantum plasmas
NASA Astrophysics Data System (ADS)
Bonitz, M.; Filinov, V. S.; Levashov, P. R.; Fortov, V. E.; Fehske, H.
2006-10-01
Coulomb crystallization is a common phenomenon in trapped (non-neutral) plasmas. In a neutral plasma, however, it is hampered by recombination of electrons and ions. Known examples are ion Coulomb crystals in white dwarf and neutron stars. Here, we predict the conditions under which a Coulomb crystal of heavy particles (e.g. ions) can form in the presence of a degenerate delocalized background of light charges (e.g. electrons): the key requirement is the mass ratio has to exceed a critical value of about 80 [1]. This leads to the prediction of novel types of crystals e.g. in hydrogen and helium. Further, we predict that holes in semiconductors can spontaneously order into a regular lattice in materials with sufficiently flat valence bands. A unified phase diagram of Coulomb crystals in two-component systems is derived and verified by first-principe path-integral Monte Carlo simulations [1-3]. [1] M. Bonitz, V.S. Filinov, V.E. Fortov, P. Levashov, H. Fehske, Phys. Rev. Lett. 95, 235006 (2005), Phys. Rev. Focus, Dec 2005 [2] M. Bonitz, V.S. Filinov, V.E. Fortov, P. Levashov, H. Fehske, J. Phys. A: Math. Gen. 39, 4717 (2006) [3] M. Bonitz, V.S. Filinov, V.E. Fortov, P. Levashov, H. Fehske, Phys. Rev. E (2006)
Integrated system for image storage, retrieval, and transmission using wavelet transform
NASA Astrophysics Data System (ADS)
Yu, Dan; Liu, Yawen; Mu, Ray Y.; Yang, Shi-Qiang
1998-12-01
Currently, much work has been done in the area of image storage and retrieval. However, the overall performance has been far from practical. A highly integrated wavelet-based image management system is proposed in this paper. By integrating wavelet-based solutions for image compression and decompression, content-based retrieval and progressive transmission, much higher performance can be achieved. The multiresolution nature of the wavelet transform has been proven to be a powerful tool to represent images. The wavelet transform decomposes the image into a set of subimages with different resolutions. From here three solutions for key aspects of image management are reached. The content-based image retrieval (CBIR) features of our system include the color, contour, texture, sample, keyword and topic information of images. The first four features can be naturally extracted from the wavelet transform coefficients. By scoring the similarity of users' requests with images in the database, those who have higher scores are noted and the user receives feedback. Image compression and decompression. Assuming that details at high resolution and diagonal directions are less visible to the human eye, a good compression ratio can be achieved. In each subimage, the wavelet coefficients are vector quantized (VQ), using the LGB algorithm, which is improved in our approach to accelerate the process. Higher compression ratio can be achieved with DPCM and entropy coding method applied together. With YIQ representation, color images can also be effectively compressed. There is a very low load on the network bandwidth by transmitting compressed image data across the network. Progressive transmission is possible by employment of the multiresolution nature of the wavelet, which makes the system respond faster and the user-interface more friendly. The system shows a high overall performance by exploring the excellent features of wavelet, and integrating key aspects of image management. An
Time transformations and Cowell's method. [for numerical integration of satellite motion equations
NASA Technical Reports Server (NTRS)
Velez, C. E.; Hilinski, S.
1978-01-01
The precise numerical integration of Cowell's equations of satellite motion is frequently performed with an independent variable s defined by an equation of the form dt = cr to the n-th power ds, where t represents time, r the radial distance from the center of attraction, c is a constant, and n is a parameter. This has been primarily motivated by the 'uniformizing' effects of such a transformation resulting in desirable 'analytic' stepsize control for elliptical orbits. This report discusses the 'proper' choice of the parameter n defining the independent variable s for various types of orbits and perturbation models, and develops a criterion for its selection.
NASA Astrophysics Data System (ADS)
Osowiecki, Gaël. D.; Madi, Mohammad; Shorubalko, Ivan; Philipoussis, Irène; Alberti, Edoardo; Scharf, Toralf; Herzig, Hans P.
2015-09-01
We show the miniaturization and parallelization of a scanning standing wave spectrometer with a long term goal of creating a compact imaging spectrometer. In our standing wave integrated Fourier transform spectrometer, light is injected with micro-lenses into several optical polymer waveguides. A piezo actuated mirror located at the waveguide end-facet can shift the interferogram to increase its sampling frequency. The spatial distribution of the standing wave intensity inside the waveguide is partially scattered out of the plane by a periodic metallic grating and recorded by a CCD camera. We present spectra acquisition for six adjacent waveguides simultaneously at a wavelength of 632.8 nm.
NASA Astrophysics Data System (ADS)
Kuznetsov, B. N.; Chesnokov, N. V.; Taraban'ko, V. E.; Kuznetsova, S. A.; Petrov, A. V.
2013-03-01
Integrated transformations of wood biomass to valuable chemicals and materials are described. They include the main biomass components separation, the conversion of cellulose to glucose, levulinic acid, biodegradable polymers and lignin - to nanoporous carbons. For wood fractionation on pure cellulose and low molecular mass lignin the methods of catalytic oxidation and exploded autohydrolysis are used. The processes of acid-catalysed hydrolysis of cellulose to glucose and levulinic acid were optimized. New methods of biodegradable polymers synthesis from lactone of levulinic acid and nanoporous carbons from lignin were suggested.
Nguyen, Thach G; Shoeiby, Mehrdad; Chu, Sai T; Little, Brent E; Morandotti, Roberto; Mitchell, Arnan; Moss, David J
2015-08-24
We demonstrate a photonic RF Hilbert transformer for broadband microwave in-phase and quadrature-phase generation based on an integrated frequency optical comb, generated using a nonlinear microring resonator based on a CMOS compatible, high-index contrast, doped-silica glass platform. The high quality and large frequency spacing of the comb enables filters with up to 20 taps, allowing us to demonstrate a quadrature filter with more than a 5-octave (3 dB) bandwidth and an almost uniform phase response.
NASA Astrophysics Data System (ADS)
Denisenko, M. V.; Munyaev, V. O.; Satanin, A. M.
2016-11-01
The parametric frequency division in a coplanar waveguide line with an integrated single-contact rf SQUID (Josephson oscillator) is discussed. It is assumed that the oscillator is excited by pump pulses whose carrier frequency can be a multiple of the plasma frequency of the oscillator. It is shown that the Josephson oscillator excited at the pump frequency can induce frequency division by emitting subharmonics that are multiples of the fundamental frequency (fractional resonances). Parameters for which parametric frequency transformation occurs are determined. The possible generalization of this effect to the quantum case in which correlated microwave photons (entangled photon states) can be generated is discussed.
Analytical expressions for partial wave two-body Coulomb transition matrices at ground-state energy
NASA Astrophysics Data System (ADS)
Kharchenko, V. F.
2016-11-01
Leaning upon the Fock method of the stereographic projection of the three-dimensional momentum space onto the four-dimensional unit sphere the possibility of the analytical solving of the Lippmann-Schwinger integral equation for the partial wave two-body Coulomb transition matrix at the ground bound state energy has been studied. In this case new expressions for the partial p-, d- and f-wave two-body Coulomb transition matrices have been obtained in the simple analytical form. The developed approach can also be extended to determine analytically the partial wave Coulomb transition matrices at the energies of excited bound states.
Coulomb-nuclear interference in 56 MeV deuteron breakup at extreme forward angle
NASA Astrophysics Data System (ADS)
Samanta, C.; Kanungo, Rituparna; Mukherjee, Sanjukta; Basu, D. N.
1995-02-01
Recently measured 12C(d,pn) 12C breakup data show a dip in the energy integrated cross section below a momentum transfer ∼ 117 MeV/ c. We analyse these data by the prior form distorted-wave Born approximation theory. Although the double humped structure of the θp = θn = 0° data exhibit the dominance of Coulomb-breakup, the pronounced asymmetry of the energy sharing data cannot be explained through Coulomb breakup only. A closer agreement to the data is obtained through Coulomb-nuclear interference and an unusual optical potential of longer range in the exit channel.
The Effects of Static Coulomb Stress Change on Southern California Earthquake Forecasts
NASA Astrophysics Data System (ADS)
Strader, A. E.; Jackson, D. D.
2013-12-01
In previous studies, we confirmed an association between static Coulomb stress change and earthquake location in southern California, when resolving stress tensors onto uniformly oriented northwest right-lateral strike-slip planes (Deng & Sykes, 1997). Using an optimized index function to convert static Coulomb stress change into normalized seismicity rates, we found that the Coulomb stress-based forecasts were not significantly more effective indicators of future earthquake locations than forecasts based on smoothed seismicity (Hiemer et al., 2011). These results were likely due to Coulomb stress uncertainties, particularly near stress singularities at the ends of fault sections where many earthquakes occurred. We evaluate hybrid Coulomb stress/smoothed seismicity earthquake forecasts against those with earthquake rates derived from only one component, within a southern California study area (32°N-37°N latitude, 122°W-114°W longitude). Using a weighted linear combination of earthquake rates derived from static Coulomb stress change and smoothed seismicity, we mitigate the effects of stress uncertainty through increasing the influence of Coulomb stress on earthquake rates with increasing distance from faults. We also evaluate time-dependent Coulomb stress earthquake forecasts based on rate-and-state friction (Toda & Enescu, 2011 and Dieterich, 1996) against a Poissonian null hypothesis, from the 10/16/1999 Hector Mine earthquake to the 4/4/2010 El Mayor Cucapah earthquake. From numerical integration, we establish a normalized seismicity rate for each day, during the target time interval, from Coulomb stress evolution and the times since all preceding source earthquakes. During each day we assume seismicity follows a Poissonian process, with expected rates defined as the rate-and-state seismicity rates. By pseudo-prospectively testing these spatial and spatiotemporal earthquake forecasts, we ascertain the role of static and quasi-static Coulomb stress change in
PREFACE: Strongly Coupled Coulomb Systems
NASA Astrophysics Data System (ADS)
Fortov, Vladimir E.; Golden, Kenneth I.; Norman, Genri E.
2006-04-01
This special issue contains papers presented at the International Conference on Strongly Coupled Coulomb Systems (SCCS) which was held during the week of 20 24 June 2005 in Moscow, Russia. The Moscow conference was the tenth in a series of conferences. The previous conferences were organized as follows. 1977: Orleans-la-Source, France, as a NATO Advanced Study Institute on Strongly Coupled Plasmas (organized by Marc Feix and Gabor J Kalman) 1982: Les Houches, France (organized by Marc Baus and Jean-Pierre Hansen) 1986: Santa Cruz, California, USA (hosted by Forrest J Rogers and Hugh E DeWitt) 1989: Tokyo, Japan (hosted by Setsuo Ichimaru) 1992: Rochester, NY, USA (hosted by Hugh M Van Horn and Setsuo Ichimaru) 1995: Binz, Germany (hosted by Wolf Dietrich Kraeft and Manfred Schlanges) 1997: Boston, Massachusetts, USA (hosted by Gabor J Kalman) 1999: St Malo, France (hosted by Claude Deutsch and Bernard Jancovici) 2002: Santa Fe, New Mexico, USA (hosted by John F Benage and Michael S Murillo) After 1995 the name of the series was changed from `Strongly Coupled Plasmas' to the present name in order to extend the topics of the conferences. The planned frequency for the future is once every three years. The purpose of these conferences is to provide an international forum for the presentation and discussion of research accomplishments and ideas relating to a variety of plasma liquid and condensed matter systems, dominated by strong Coulomb interactions between their constituents. Strongly coupled Coulomb systems encompass diverse many-body systems and physical conditions. Each meeting has seen an evolution of topics and emphasis as new discoveries and new methods appear. This year, sessions were organized for invited presentations and posters on dense plasmas and warm matter, astrophysics and dense hydrogen, non-neutral and ultracold plasmas, dusty plasmas, condensed matter 2D and layered charged-particle systems, Coulomb liquids, and statistical theory of SCCS. Within
Coulombic contribution and fat center vortex model
Rafibakhsh, Shahnoosh; Deldar, Sedigheh
2007-02-27
The fat (thick) center vortex model is one of the phenomenological models which is fairly successful to interpret the linear potential between static sources. However, the Coulombic part of the potential has not been investigated by the model yet. In an attempt to get the Coulombic contribution and to remove the concavity of the potentials, we are studying different vortex profiles and vortex sizes.
NASA Astrophysics Data System (ADS)
Fedotov, I. A.; Polyanin, A. D.
2011-09-01
Broad classes of nonlinear equations of mathematical physics are described that admit order reduction by applying the von Mises transformation (with the unknown function used as a new independent variable and with a suitable partial derivative used as a new dependent variable) and by applying the Crocco transformation (with the first and second partial derivatives used as new independent and dependent variables, respectively). Associated Bäcklund transformations are constructed that connect evolution equations of general form (their special cases include Burgers, Korteweg-de Vries, and Harry Dym type equations and many other nonlinear equations of mathematical physics). Transformations are indicated that reduce the order of hydrodynamic-type equations of higher orders. The generalized Calogero equation and a number of other new integrable nonlinear equations, reducible to linear equations, are considered.
Matharu, Zimple; Patel, Dipali; Gao, Yandong; Haque, Amranul; Zhou, Qing; Revzin, Alexander
2014-09-02
We developed a cell-culture/biosensor platform consisting of aptamer-modified Au electrodes integrated with reconfigurable microfluidics for monitoring of transforming growth factor-beta 1 (TGF-β1), an important inflammatory and pro-fibrotic cytokine. Aptamers were thiolated, labeled with redox reporters, and self-assembled on gold surfaces. The biosensor was determined to be specific for TGF-β1 with an experimental detection limit of 1 ng/mL and linear range extending to 250 ng/mL. Upon determining figures of merit, aptasensor was miniaturized and integrated with human hepatic stellate cells inside microfluidic devices. Reconfigurable microfluidics were developed to ensure that seeding of "sticky" stromal cells did not foul the electrode and compromise sensor performance. This microsystem with integrated aptasensors was used to monitor TGF-β1 release from activated stellate cells over the course of 20 h. The electrochemical response went down upon infusing anti-TGF-β1 antibodies into the microfluidic devices containing activated stellate cells. To further validate aptasensor responses, stellate cells were stained for markers of activation (e.g., alpha smooth muscle actin) and were also tested for presence of TGF-β1 using enzyme linked immunosorbent assay (ELISA). Given the importance of TGF-β1 as a fibrogenic signal, a microsystem with integrated biosensors for local and continuous detection of TGF-β1 may prove to be an important tool to study fibrosis of the liver and other organs.
NASA Astrophysics Data System (ADS)
Gao, Yingjie; Zhang, Jinhai; Yao, Zhenxing
2016-06-01
The symplectic integration method is popular in high-accuracy numerical simulations when discretizing temporal derivatives; however, it still suffers from time-dispersion error when the temporal interval is coarse, especially for long-term simulations and large-scale models. We employ the inverse time dispersion transform (ITDT) to the third-order symplectic integration method to reduce the time-dispersion error. First, we adopt the pseudospectral algorithm for the spatial discretization and the third-order symplectic integration method for the temporal discretization. Then, we apply the ITDT to eliminate time-dispersion error from the synthetic data. As a post-processing method, the ITDT can be easily cascaded in traditional numerical simulations. We implement the ITDT in one typical exiting third-order symplectic scheme and compare its performances with the performances of the conventional second-order scheme and the rapid expansion method. Theoretical analyses and numerical experiments show that the ITDT can significantly reduce the time-dispersion error, especially for long travel times. The implementation of the ITDT requires some additional computations on correcting the time-dispersion error, but it allows us to use the maximum temporal interval under stability conditions; thus, its final computational efficiency would be higher than that of the traditional symplectic integration method for long-term simulations. With the aid of the ITDT, we can obtain much more accurate simulation results but with a lower computational cost.
Flow integration transform: detecting shapes in matrix-array 3D ultrasound data
NASA Astrophysics Data System (ADS)
Stetten, George D.; Caines, Michael; von Ramm, Olaf T.
1995-03-01
Matrix-array ultrasound produces real-time 3D images of the heart, by employing a square array of transducers to steer the ultrasound beam in three dimensions electronically with no moving parts. Other 3D modalities such as MR, MUGA, and CT require the use of gated studies, which combine many cardiac cycles to produce a single average cycle. Three- dimensional ultrasound eliminates this restriction, in theory permitting the continuous measurement of cardiac ventricular volume, which we call the volumetricardiogram. Towards implementing the volumetricardiogram, we have developed the flow integration transform (FIT), which operates on a 2D slice within the volumetric ultrasound data. The 3D ultrasound machine's scan converter produces a set of such slices in real time, at any desired location and orientation, to which the FIT may then be applied. Although lacking rotational or scale invariance, the FIT is designed to operate in dedicated hardware where an entire transform could be completed within a few microseconds with present integrated circuit technology. This speed would permit the application of a large battery of test shapes, or the evolution of the test shape to converge on that of the actual target.
NASA Astrophysics Data System (ADS)
Liu, Chongxuan; Szecsody, Jim E.; Zachara, John M.; Ball, William P.
The generalized integral transform technique (GITT) is applied to solve the one-dimensional advection-dispersion equation (ADE) in heterogeneous porous media coupled with either linear or nonlinear sorption and decay. When both sorption and decay are linear, analytical solutions are obtained using the GITT for one-dimensional ADEs with spatially and temporally variable flow and dispersion coefficient and arbitrary initial and boundary conditions. When either sorption or decay is nonlinear the solutions to ADEs with the GITT are hybrid analytical-numerical. In both linear and nonlinear cases, the forward and inverse integral transforms for the problems described in the paper are apparent and straightforward. Some illustrative examples with linear sorption and decay are presented to demonstrate the application and check the accuracy of the derived analytical solutions. The derived hybrid analytical-numerical solutions are checked against a numerical approach and demonstratively applied to a nonlinear transport example, which simulates a simplified system of iron oxide bioreduction with nonlinear sorption and nonlinear reaction kinetics.
Zhang, Min; Jiang, Shaotong; Zheng, Juan; Zheng, Zhi; Li, Xingjiang; Pan, Lijun; Luo, Shuizhong
2015-08-01
To construct a system of genetic transformation suitable for Rhizopus oryzae, we constructed a single-exchange vector pBS-hygro carrying hygromycin B resistance gene (hph) as its selective marker using gene splicing by overlap extension PCR (SOE PCR) technique. We introduced this recombinant vector into Rhizopus oryzae AS 3.819 by PEG/CaCl2-mediated transformation of protoplast, electroporation of protoplast and germinated spores; and we studied the effects of hydrolysis time, field strength and spore germination time on transformation frequency. We conducted quantitative real-time PCR (qPCR) assay to determine the gene copy number of ldhA integrated in the genome of R. oryzae transformants and its effect on the stability of transformants. We successfully achieved R. oryzae transformants integrated with pBS-hygro-ldhA vector. The optimal hydrolysis time for protoplast production was 140 min, and the optimal field strength of electroporation pulse for protoplast was 13 kV/cm. The optimal germination time of spores for electroporation was 2.5 h, and the optimal field strength of electroporation pulse was 14 kV/cm. The transformation frequency of method based on germinated spores was generally higher than the methods based on protoplast. The qPCR test results suggested that transformants with high copy number of integration in a certain range were relatively stable. Our results provided basis and support for metabolic regulation and genetic engineering breeding of R. oryzae.
TRANSVERSE MERCATOR MAP PROJECTION OF THE SPHEROID USING TRANSFORMATION OF THE ELLIPTIC INTEGRAL
NASA Technical Reports Server (NTRS)
Wallis, D. E.
1994-01-01
the (irreducible) Incomplete Elliptic Integral of the 2nd Kind, the value for the tangent of one half the amplitude of the Elliptic Integral of the 2nd Kind is now known. The elliptic integral may now be computed by any desired method, and the result will be the Gauss-Kruger Transverse Mercator Projection. This result is a consequence of the fact that these steps produce a computation of real distance along the image (in the plane) of the principal meridian, and an analytic continuation of the distance at points that don't lie on the principal meridian. The elliptic-integral method used by this program is one of the "transformations of the elliptic integral" (similar to Landen's Transformation), appearing in standard handbooks of mathematical functions. Only elementary transcendental functions are utilized. The program output is the conventional (as used by the mapping agencies) cartesian coordinates, in meters, of the Transverse Mercator projection. The origin is at the intersection of the principal meridian and the equator. This FORTRAN77 program was developed on an IBM PC series computer equipped with an Intel Math Coprocessor. Double precision complex arithmetic and transcendental functions are needed to support a projection accuracy of 1 mm. Because such functions are not usually part of the FORTRAN library, the needed functions have been explicitly programmed and included in the source code. The program was developed in 1989. TRANSVERSE MERCATOR MAP PROJECTION OF THE SPHEROID USING TRANSFORMATIONS OF THE ELLIPTIC INTEGRAL is a copyrighted work with all copyright vested in NASA.
Wave operator in few-body quantum scattering with Coulomb-like interactions
Kroeger, H.
1985-01-01
Functional analytical methods like strong approximation of operator-valued functions and Dunfords' calculus are applied to yield a contour integral representation with a finite contour of wave operators for nonrelativistic potential scattering with Coulomb and short-range interactions, which avoids high singularities of Coulomb-like Green's functions of stationary scattering theory. The Green's function is the unique solution of the resolvent equation, which has an A-proper kernel allowing projector methods for its solution.
NASA Technical Reports Server (NTRS)
Pawloski, Janice S.
2001-01-01
This project uses the integral transform technique to model the problem of nanotube behavior as an axially symmetric system of shells. Assuming that the nanotube behavior can be described by the equations of elasticity, we seek a stress function x which satisfies the biharmonic equation: del(exp 4) chi = [partial deriv(r(exp 2)) + partial deriv(r) + partial deriv(z(exp 2))] chi = 0. The method of integral transformations is used to transform the differential equation. The symmetry with respect to the z-axis indicates that we only need to consider the sine transform of the stress function: X(bar)(r,zeta) = integral(from 0 to infinity) chi(r,z)sin(zeta,z) dz.
NASA Technical Reports Server (NTRS)
Pawloski, Janice S.
2001-01-01
This project uses the integral transform technique to model the problem of nanotube behavior as an axially symmetric system of shells. Assuming that the nanotube behavior can be described by the equations of elasticity, we seek a stress function x which satisfies the biharmonic equation: del(exp 4) chi = [partial deriv(r(exp 2)) + partial deriv(r) + partial deriv(z(exp 2))] chi = 0. The method of integral transformations is used to transform the differential equation. The symmetry with respect to the z-axis indicates that we only need to consider the sine transform of the stress function: X(bar)(r,zeta) = integral(from 0 to infinity) chi(r,z)sin(zeta,z) dz.
The Coulombic Lattice Potential of Ionic Compounds: The Cubic Perovskites.
ERIC Educational Resources Information Center
Francisco, E.; And Others
1988-01-01
Presents coulombic models representing the particles of a system by point charges interacting through Coulomb's law to explain coulombic lattice potential. Uses rubidium manganese trifluoride as an example of cubic perovskite structure. Discusses the effects on cluster properties. (CW)
The Coulombic Lattice Potential of Ionic Compounds: The Cubic Perovskites.
ERIC Educational Resources Information Center
Francisco, E.; And Others
1988-01-01
Presents coulombic models representing the particles of a system by point charges interacting through Coulomb's law to explain coulombic lattice potential. Uses rubidium manganese trifluoride as an example of cubic perovskite structure. Discusses the effects on cluster properties. (CW)
Al Khawaja, U.
2010-05-15
We derive the integrability conditions of nonautonomous nonlinear Schroedinger equations using the Lax pair and similarity transformation methods. We present a comparative analysis of these integrability conditions with those of the Painleve method. We show that while the Painleve integrability conditions restrict the dispersion, nonlinearity, and dissipation/gain coefficients to be space independent and the external potential to be only a quadratic function of position, the Lax Pair and the similarity transformation methods allow for space-dependent coefficients and an external potential that is not restricted to the quadratic form. The integrability conditions of the Painleve method are retrieved as a special case of our general integrability conditions. We also derive the integrability conditions of nonautonomous nonlinear Schroedinger equations for two- and three-spacial dimensions.
Dynamical Coulomb blockade of tunnel junctions driven by alternating voltages
NASA Astrophysics Data System (ADS)
Grabert, Hermann
2015-12-01
The theory of the dynamical Coulomb blockade is extended to tunneling elements driven by a time-dependent voltage. It is shown that, for standard setups where an external voltage is applied to a tunnel junction via an impedance, time-dependent driving entails an excitation of the modes of the electromagnetic environment by the applied voltage. Previous approaches for ac driven circuits need to be extended to account for the driven bath modes. A unitary transformation involving also the variables of the electromagnetic environment is introduced which allows us to split off the time dependence from the Hamiltonian in the absence of tunneling. This greatly simplifies perturbation-theoretical calculations based on treating the tunneling Hamiltonian as a perturbation. In particular, the average current flowing in the leads of the tunnel junction is studied. Explicit results are given for the case of an applied voltage with a constant dc part and a sinusoidal ac part. The connection with standard dynamical Coulomb blockade theory for constant applied voltage is established. It is shown that an alternating voltage source reveals significant additional effects caused by the electromagnetic environment. The hallmark of the dynamical Coulomb blockade in ac driven devices is a suppression of higher harmonics of the current by the electromagnetic environment. The theory presented basically applies to all tunneling devices driven by alternating voltages.
Correlation functions of Coulomb branch operators
NASA Astrophysics Data System (ADS)
Gerchkovitz, Efrat; Gomis, Jaume; Ishtiaque, Nafiz; Karasik, Avner; Komargodski, Zohar; Pufu, Silviu S.
2017-01-01
We consider the correlation functions of Coulomb branch operators in four-dimensional N = 2 Superconformal Field Theories (SCFTs) involving exactly one antichiral operator. These extremal correlators are the "minimal" non-holomorphic local observables in the theory. We show that they can be expressed in terms of certain determinants of derivatives of the four-sphere partition function of an appropriate deformation of the SCFT. This relation between the extremal correlators and the deformed four-sphere partition function is non-trivial due to the presence of conformal anomalies, which lead to operator mixing on the sphere. Evaluating the deformed four-sphere partition function using supersymmetric localization, we compute the extremal correlators explicitly in many interesting examples. Additionally, the representation of the extremal correlators mentioned above leads to a system of integrable differential equations. We compare our exact results with previous perturbative computations and with the four-dimensional tt ∗ equations. We also use our results to study some of the asymptotic properties of the perturbative series expansions we obtain in N = 2 SQCD.
A new method to calculate the beam charge for an integrating current transformer
Wu Yuchi; Han Dan; Zhu Bin; Dong Kegong; Tan Fang; Gu Yuqiu
2012-09-15
The integrating current transformer (ICT) is a magnetic sensor widely used to precisely measure the charge of an ultra-short-pulse charged particle beam generated by traditional accelerators and new laser-plasma particle accelerators. In this paper, we present a new method to calculate the beam charge in an ICT based on circuit analysis. The output transfer function shows an invariable signal profile for an ultra-short electron bunch, so the function can be used to evaluate the signal quality and calculate the beam charge through signal fitting. We obtain a set of parameters in the output function from a standard signal generated by an ultra-short electron bunch (about 1 ps in duration) at a radio frequency linear electron accelerator at Tsinghua University. These parameters can be used to obtain the beam charge by signal fitting with excellent accuracy.
Simulation of the superconducting multiturn flux transformer integrated with a coplanar resonator
NASA Astrophysics Data System (ADS)
Yi, H. R.; Zhang, Y.; Klein, N.
2000-06-01
The analysis of the structure of a superconducting multiturn flux transformer integrated with a coplanar resonator for radio-frequency superconducting quantum interference devices is described. Electromagnetic simulations indicate that the loss is dominated by the high loss tangent of the dielectric film used for the separation of the upper and lower superconducting films. The simulated current distribution at its resonant frequency shows that the highest current density is distributed on the multiturn input coil. This current distribution leads to a very high loss when the loss tangent of the dielectric film is high. However, for the same loss tangent of the dielectric film, it is possible to get a reasonably high unloaded quality factor by providing a normal shunt for the multiturn input coil.
NASA Astrophysics Data System (ADS)
Engel, Megan C.; Ritchie, Dustin B.; Foster, Daniel A. N.; Beach, Kevin S. D.; Woodside, Michael T.
2014-12-01
The energy landscapes that drive structure formation in biopolymers are difficult to measure. Here we validate experimentally a novel method to reconstruct landscape profiles from single-molecule pulling curves using an inverse Weierstrass transform (IWT) of the Jarzysnki free-energy integral. The method was applied to unfolding measurements of a DNA hairpin, replicating the results found by the more-established weighted histogram (WHAM) and inverse Boltzmann methods. Applying both WHAM and IWT methods to reconstruct the folding landscape for a RNA pseudoknot having a stiff energy barrier, we found that landscape features with sharper curvature than the force probe stiffness could not be recovered with the IWT method. The IWT method is thus best for analyzing data from stiff force probes such as atomic force microscopes.
NASA Technical Reports Server (NTRS)
Verber, C. M.; Vahey, D. W.; Wood, V. E.; Kenan, R. P.; Hartman, N. F.
1977-01-01
The possibility of producing an integrated optics data processing device based upon Fourier transformations or other parallel processing techniques, and the ways in which such techniques may be used to upgrade the performance of present and projected NASA systems were investigated. Activities toward this goal include; (1) production of near-diffraction-limited geodesic lenses in glass waveguides; (2) development of grinding and polishing techniques for the production of geodesic lenses in LiNbO3 waveguides; (3) development of a characterization technique for waveguide lenses; and (4) development of a theory for corrected aspheric geodesic lenses. A holographic subtraction system was devised which should be capable of rapid on-board preprocessing of a large number of parallel data channels. The principle involved is validated in three demonstrations.
Geometric BVPs, Hardy spaces, and the Cauchy integral and transform on regions with corners
NASA Astrophysics Data System (ADS)
Loya, Paul
In this paper we give a new perspective on the Cauchy integral and transform and Hardy spaces for Dirac-type operators on manifolds with corners of codimension two. Instead of considering Banach or Hilbert spaces, we use polyhomogeneous functions on a geometrically "blown-up" version of the manifold called the total boundary blow-up introduced by Mazzeo and Melrose [R.R. Mazzeo, R.B. Melrose, Analytic surgery and the eta invariant, Geom. Funct. Anal. 5 (1) (1995) 14-75]. These polyhomogeneous functions are smooth everywhere on the original manifold except at the corners where they have a "Taylor series" (with possible log terms) in polar coordinates. The main application of our analysis is a complete Fredholm theory for boundary value problems of Dirac operators on manifolds with corners of codimension two.
Hait, Subrata; Tare, Vinod
2012-05-01
Transformation and availability of nutrients and some heavy metals were assessed during the integrated composting-vermicomposting of both primary sewage sludge (PSS) and waste activated sewage sludge (WAS) using matured vermicompost as indigenous bulking material and employing Eisenia fetida as earthworm species. Vermicomposting resulted in significant increase in total N (TN) (PSS: 41.7-64.6%, F=11.6, P<0.05; WAS: 36.4-58.6%, F=6.4, P<0.05), water soluble N (WSN) (PSS: 37.1-50.5%, F=30.1, P<0.05; WAS: 40.1-53.0%, F=27.6, P<0.05), total P (TP) (PSS: 39.9-69.8%, F=27.1, P<0.05; WAS: 32.2-56.6%, F=21.4, P<0.05) and water soluble P (WSP) (PSS: 25.2-34.3%, F=163.9, P<0.05; WAS: 24.1-34.2%, F=144.3, P<0.05) as compared to the initial compost material depending on different experimental conditions. The study demonstrated that the vermicomposting significantly improved the availability of nutrients in sewage sludges. In addition, vermicomposting considerably reduced the availability of heavy metals except Fe and Mn, presumably by forming organic-bound complexes in spite of several fold increase in their total content. The environmental conditions (i.e., temperature and relative humidity), in general, showed significant effect on the transformation and availability of nutrients and heavy metals. There was no effect of earthworm density on the transformation and availability of heavy metals and nutrients except N and P, possibly due to prior exposure during acclimation period in sewage sludge. Copyright © 2012 Elsevier Inc. All rights reserved.
Fedele, L A; Even, J; Garon, C F; Donner, L; Sherr, C J
1981-01-01
The integrated DNA provirus of the Gardner-Arnstein (GA) strain of feline sarcoma virus (FeSV) was molecularly cloned in a bacteriophage lambda vector. The cloned DNA fragment is 14.4 kilobase pairs long and contains a 6.7-kilobase provirus flanked by cellular sequences derived from nonproductively transformed mink cells. Transfection of mouse NIH/3T3 cells with the cloned DNA fragment induced foci of transformation at efficiencies of 10(4) focus-forming units/pmol of sarcoma virus DNA. Restriction endonuclease mapping and heteroduplex analyses were used to compare the GA-FeSV provirus with that of Snyder-Theilen (ST)-FeSV, a second strain that contains homologous transformation-specific sequences (v-fes). Both viruses have the general structure 5'-gag-fes-env-c region-3', each having retained portions of the feline leukemia virus (FeLV) gag and env genes. In addition to segments shared by the two sarcoma viruses, GA-FeSV contains 1.7 kilobases of extra sequences not found in ST-FeSV. Of these, at least 400-500 base pairs located near the 5' end of v-fes encode a portion of the GA-FeSV polyprotein; the remaining 1.2 kilobases are derived from the FeLV env gene but do not appear to encode any detectable product related to the FeLV envelope glycoprotein. The close homology of the v-fes sequences shows that GA- and ST-FeSV were formed by recombination of FeLV with similar portions of a cat cellular gene (c-fes). Images PMID:6270655
NASA Astrophysics Data System (ADS)
Rossbach, P. C.
1985-12-01
The calculation of the Discrete Fourier Transform has long been a significant bottleneck in many Digital Signal Processing applications. With the arrival of Very Large Scale Integration and new DFT algorithms, system architectures that significantly reduce the DFT bottleneck are possible. This thesis addresses the design, simulation, implementation, and testing of the control circuitry for a high speed, VLSI Winograd Fourier Transform (WFT) processor. Three WFT processors are combined into a pipelined architecture that is capable of computing a 4080-point DFT on complex input data approximately every 120 microseconds when operating with 70 MHz clock signals. The chip control architecture features a special Programmable Logic Array (PLA) to control the on-chip arithmetic circuitry, and a dense, 54K ROM to generate data addresses for the external RAM. The PLA controller was fabricated in 3 micron CMOS and functioned properly for clock rates of over 60 MHz. The address generator ROM was designed and submitted for fabrication in 3 micron CMOS, and SPICE simulations predict an access time of 60 nanoseconds. Software that automatically generates a ROM layout description from a data file was developed to ensure the correctness of the final design. The transistor minimization procedure i s based on a graph partitioning heuristic, and the drain removal procedure is based on an algorithm that near-optimally solves the Traveling Salesman Problem.
Three New (2+1)-dimensional Integrable Systems and Some Related Darboux Transformations
NASA Astrophysics Data System (ADS)
Guo, Xiu-Rong
2016-06-01
We introduce two operator commutators by using different-degree loop algebras of the Lie algebra A1, then under the framework of zero curvature equations we generate two (2+1)-dimensional integrable hierarchies, including the (2+1)-dimensional shallow water wave (SWW) hierarchy and the (2+1)-dimensional Kaup-Newell (KN) hierarchy. Through reduction of the (2+1)-dimensional hierarchies, we get a (2+1)-dimensional SWW equation and a (2+1)-dimensional KN equation. Furthermore, we obtain two Darboux transformations of the (2+1)-dimensional SWW equation. Similarly, the Darboux transformations of the (2+1)-dimensional KN equation could be deduced. Finally, with the help of the spatial spectral matrix of SWW hierarchy, we generate a (2+1) heat equation and a (2+1) nonlinear generalized SWW system containing inverse operators with respect to the variables x and y by using a reduction spectral problem from the self-dual Yang-Mills equations. Supported by the National Natural Science Foundation of China under Grant No. 11371361, the Shandong Provincial Natural Science Foundation of China under Grant Nos. ZR2012AQ011, ZR2013AL016, ZR2015EM042, National Social Science Foundation of China under Grant No. 13BJY026, the Development of Science and Technology Project under Grant No. 2015NS1048 and A Project of Shandong Province Higher Educational Science and Technology Program under Grant No. J14LI58
Crystallization in two-component Coulomb systems.
Bonitz, M; Filinov, V S; Fortov, V E; Levashov, P R; Fehske, H
2005-12-02
The analysis of Coulomb crystallization is extended from one-component to two-component plasmas. Critical parameters for the existence of Coulomb crystals are derived for both classical and quantum crystals. In the latter case, a critical mass ratio of the two charged components is found, which is of the order of 80. Thus, holes in semiconductors with sufficiently flat valence bands are predicted to spontaneously order into a regular lattice. Such hole crystals are intimately related to ion Coulomb crystals in white dwarf and neutron stars as well as to ion crystals produced in the laboratory. A unified phase diagram of two-component Coulomb crystals is presented and is verified by first-principles computer simulations.
Coulomb flux tube on the lattice
NASA Astrophysics Data System (ADS)
Chung, Kristian; Greensite, Jeff
2017-08-01
In Coulomb gauge a longitudinal electric field is generated instantaneously with the creation of a static quark-antiquark pair. The field due to the quarks is a sum of two contributions, one from the quark and one from the antiquark, and there is no obvious reason that this sum should fall off exponentially with distance from the sources. We show here, however, from numerical simulations in pure SU(2) lattice gauge theory, that the color Coulomb electric field does in fact fall off exponentially with transverse distance away from a line joining static quark-antiquark sources, indicating the existence of a color Coulomb flux tube, and the absence of long-range Coulomb dipole fields.
Stahl, Bernd Carsten; Wakunuma, Kutoma; Rainey, Stephen; Hansen, Christian
2017-01-01
Research on Brain Computer Interfaces (BCI) often aims to provide solutions for vulnerable populations, such as individuals with diseases, conditions or disabilities that keep them from using traditional interfaces. Such research thereby contributes to the public good. This contribution to the public good corresponds to a broader drive of research and funding policy that focuses on promoting beneficial societal impact. One way of achieving this is to engage with the public. In practical terms this can be done by integrating civil society organisations (CSOs) in research. The open question at the heart of this paper is whether and how such CSO integration can transform the research and contribute to the public good. To answer this question the paper describes five detailed qualitative case studies of research projects including CSOs. The paper finds that transformative impact of CSO integration is possible but by no means assured. It provides recommendations on how transformative impact can be promoted.
Wakunuma, Kutoma; Rainey, Stephen; Hansen, Christian
2017-01-01
Research on Brain Computer Interfaces (BCI) often aims to provide solutions for vulnerable populations, such as individuals with diseases, conditions or disabilities that keep them from using traditional interfaces. Such research thereby contributes to the public good. This contribution to the public good corresponds to a broader drive of research and funding policy that focuses on promoting beneficial societal impact. One way of achieving this is to engage with the public. In practical terms this can be done by integrating civil society organisations (CSOs) in research. The open question at the heart of this paper is whether and how such CSO integration can transform the research and contribute to the public good. To answer this question the paper describes five detailed qualitative case studies of research projects including CSOs. The paper finds that transformative impact of CSO integration is possible but by no means assured. It provides recommendations on how transformative impact can be promoted. PMID:28207882
Recent developments in Coulomb breakup calculations
Capel, P.
2008-05-12
The theory of reactions applied to Coulomb breakup of loosely-bound projectiles is reviewed. Both the Continuum Discretized Coupled Channel (CDCC) and time-dependent models are described. Recent results about sensitivity of breakup calculations to the projectile wave function are reviewed. Analyses of the extraction of radiative-capture cross section from Coulomb breakup measurements are presented. Current developments in breakup theory are also mentioned.
Parallel Molecular Dynamics of Coulomb Clusters
NASA Astrophysics Data System (ADS)
Kishimoto, Tokunari; Totsuji, Chieko; Tsuruta, Kenji; Totsuji, Hiroo
2000-10-01
Using parallel computers, we perform large-scale molecular dynamics (MD) simulations of Coulomb clusters in a spherical trapping field. Long-range Coulomb forces are calculated efficiently using the fast multipole method (FMM). Previously Hasse and Avilov [1] have performed numerical analysis of Coulomb clusters, and predicted a crossover between the energy curve of Coulomb clusters and that of finite bcc crystals around N = 10^6. Another prediction [2] has been reported around N = 10^5. Recently, experimental observation of Be^+ clusters in ion trap [3] indicated that structure of N = 8 *10^4 was similar to bcc single crystal. We perform direct simulations of Coulomb clusters of system sizes N = 10^5-10^6. We report preliminary results on 10^5 system: Radial distribution and the Laue-pattern analysis indicates structural evolution of the cluster. The correlation energy of the cluster is found to be lower than finite bcc crystal of the same size. We will show results for larger systems (10^6) and the N dependence of structure and energy of the Coulomb clusters around the crossover region. [1] R. W. Hasse and V. V. Avilov, Phys. Rev. A 44, 4506 (1991). [2] D. H. E. Dubin, Phys. Rev. A 40, 1140 (1989). [3] W. M. Itano et al., Science 279, 686 (1998).
Coulomb crystal mass spectrometry in a digital ion trap
NASA Astrophysics Data System (ADS)
Deb, Nabanita; Pollum, Laura L.; Smith, Alexander D.; Keller, Matthias; Rennick, Christopher J.; Heazlewood, Brianna R.; Softley, Timothy P.
2015-03-01
We present a mass spectrometric technique for identifying the masses and relative abundances of Coulomb-crystallized ions held in a linear Paul trap. A digital radio-frequency wave form is employed to generate the trapping potential, as this can be cleanly switched off, and static dipolar fields are subsequently applied to the trap electrodes for ion ejection. Close to 100% detection efficiency is demonstrated for Ca+ and CaF+ ions from bicomponent Ca+-CaF+ Coulomb crystals prepared by the reaction of Ca+ with CH3F . A quantitative linear relationship is observed between ion number and the corresponding integrated time-of-flight (TOF) peak, independent of the ionic species. The technique is applicable to a diverse range of multicomponent Coulomb crystals—demonstrated here for Ca+-NH 3+ -NH 4+ and Ca+-CaOH +-CaOD + crystals—and will facilitate the measurement of ion-molecule reaction rates and branching ratios in complicated reaction systems.
NASA Astrophysics Data System (ADS)
Tayyab, Muhammad; Zhou, Jianzhong; Dong, Xiaohua; Ahmad, Ijaz; Sun, Na
2017-09-01
Artificial neural network (ANN) models combined with time series decomposition are widely employed to calculate the river flows; however, the influence of the application of diverse decomposing approaches on assessing correctness is inadequately compared and examined. This study investigates the certainty of monthly streamflow by applying ANNs including feed forward back propagation neural network and radial basis function neural network (RBFNN) models integrated with discrete wavelet transform (DWT), at Jinsha River basin in the upper reaches of Yangtze River of China. The effect of the noise factor of the decomposed time series on the prediction correctness has also been argued in this paper. Data have been analyzed by comparing the simulation outputs of the models with the correlation coefficient (R) root mean square errors, mean absolute errors, mean absolute percentage error and Nash-Sutcliffe Efficiency. Results show that time series decomposition technique DWT contributes in improving the accuracy of streamflow prediction, as compared to single ANN's. The detailed comparative analysis showed that the RBFNN integrated with DWT has better forecasting capabilities as compared to other developed models. Moreover, for high-precision streamflow prediction, the high-frequency section of the original time series is very crucial, which is understandable in flood season.
NASA Astrophysics Data System (ADS)
Hu, Wenjing
2017-08-01
This paper uses Fourier’s triple integral transform method to simplify the calculation of the non-homogeneous wave equations of the time-varying electromagnetic field. By adding several special definite conditions to the wave equation, it becomes a mathematical problem of definite condition. Then by using Fourier’s triple integral transform method, this three-dimension non-homogeneous partial differential wave equation is changed into an ordinary differential equation. Through the solution to this ordinary differential equation, the expression of the relationship between the time-varying scalar potential and electromagnetic wave excitation source is developed precisely. This method simplifies the solving process effectively.
The algebra of the quantum nondegenerate three-dimensional Kepler-Coulomb potential
Tanoudis, Y.; Daskaloyannis, C.
2011-07-15
The classical generalized Kepler-Coulomb potential, introduced by Verrier and Evans, corresponds to a quantum superintegrable system, with quadratic and quartic integrals of motion. In this paper we show that the algebra of the integrals is a quadratic ternary algebra, i.e a quadratic extension of a Lie triple system.
Slave rotor approach to dynamically screened Coulomb interactions in solids
NASA Astrophysics Data System (ADS)
Krivenko, I. S.; Biermann, S.
2015-04-01
Recent studies of dynamical screening of the electronic Coulomb interactions in solids have revived interest in lattice models of correlated fermions coupled to bosonic degrees of freedom (Hubbard-Holstein-type models). We propose a new dynamical mean-field-based approach to dynamically screened Coulomb interactions. In the effective Anderson-Holstein model, a transformation to slave rotors [S. Florens and A. Georges, Phys. Rev. B 66, 165111 (2002), 10.1103/PhysRevB.66.165111] is performed to decouple the dynamical part of the interaction. This transformation allows for a systematic derivation and analysis of recently introduced approximate schemes for the solution of dynamical impurity problems, in particular, the Bose factor ansatz within the dynamic atomic limit approximation (DALA) with and without Lang-Firsov correction. More importantly still, it suggests an optimized choice for a Bose factor in the sense of the variational principle of Feynman and Peierls. We demonstrate the accuracy of our scheme and present a comparison to calculations within the DALA.
Bates, Jason H T; Sobel, Burton E
2003-05-01
This is the third in a series of four articles developed for the readers of Coronary Artery Disease. Without language ideas cannot be articulated. What may not be so immediately obvious is that they cannot be formulated either. One of the essential languages of cardiology is mathematics. Unfortunately, medical education does not emphasize, and in fact, often neglects empowering physicians to think mathematically. Reference to statistics, conditional probability, multicompartmental modeling, algebra, calculus and transforms is common but often without provision of genuine conceptual understanding. At the University of Vermont College of Medicine, Professor Bates developed a course designed to address these deficiencies. The course covered mathematical principles pertinent to clinical cardiovascular and pulmonary medicine and research. It focused on fundamental concepts to facilitate formulation and grasp of ideas.This series of four articles was developed to make the material available for a wider audience. The articles will be published sequentially in Coronary Artery Disease. Beginning with fundamental axioms and basic algebraic manipulations they address algebra, function and graph theory, real and complex numbers, calculus and differential equations, mathematical modeling, linear system theory and integral transforms and statistical theory. The principles and concepts they address provide the foundation needed for in-depth study of any of these topics. Perhaps of even more importance, they should empower cardiologists and cardiovascular researchers to utilize the language of mathematics in assessing the phenomena of immediate pertinence to diagnosis, pathophysiology and therapeutics. The presentations are interposed with queries (by Coronary Artery Disease abbreviated as CAD) simulating the nature of interactions that occurred during the course itself. Each article concludes with one or more examples illustrating application of the concepts covered to
Bae, Sunwoong; Park, Seunghye; Kim, Jung; Choi, Jong Seob; Kim, Kyung Hoon; Kwon, Donguk; Jin, EonSeon; Park, Inkyu; Kim, Do Hyun; Seo, Tae Seok
2015-12-16
Superior green algal cells showing high lipid production and rapid growth rate are considered as an alternative for the next generation green energy resources. To achieve the biomass based energy generation, transformed microalgae with superlative properties should be developed through genetic engineering. Contrary to the normal cells, microalgae have rigid cell walls, so that target gene delivery into cells is challengeable. In this study, we report a ZnO nanowire-incorporated microdevice for a high throughput microalgal transformation. The proposed microdevice was equipped with not only a ZnO nanowire in the microchannel for gene delivery into cells but also a pneumatic polydimethylsiloxane (PDMS) microvalve to modulate the cellular attachment and detachment from the nanowire. As a model, hygromycin B resistance gene cassette (Hyg3) was functionalized on the hydrothermally grown ZnO nanowires through a disulfide bond and released into green algal cells, Chlamydomonas reinhardtii, by reductive cleavage. During Hyg3 gene delivery, a monolithic PDMS membrane was bent down, so that algal cells were pushed down toward ZnO nanowires. The supply of vacuum in the pneumatic line made the PDMS membrane bend up, enabling the gene delivered algal cells to be recovered from the outlet of the microchannel. We successfully confirmed Hyg3 gene integrated in microalgae by amplifying the inserted gene through polymerase chain reaction (PCR) and DNA sequencing. The efficiency of the gene delivery to algal cells using the ZnO nanowire-incorporated microdevice was 6.52 × 10(4)- and 9.66 × 10(4)-fold higher than that of a traditional glass bead beating and electroporation.
Strong-field ionization via a high-order Coulomb-corrected strong-field approximation
NASA Astrophysics Data System (ADS)
Klaiber, Michael; Daněk, Jiří; Yakaboylu, Enderalp; Hatsagortsyan, Karen Z.; Keitel, Christoph H.
2017-02-01
Signatures of the Coulomb corrections in the photoelectron momentum distribution during laser-induced ionization of atoms or ions in tunneling and multiphoton regimes are investigated analytically in the case of a one-dimensional problem. A high-order Coulomb-corrected strong-field approximation is applied, where the exact continuum state in the S matrix is approximated by the eikonal Coulomb-Volkov state including the second-order corrections to the eikonal. Although without high-order corrections our theory coincides with the known analytical R -matrix (ARM) theory, we propose a simplified procedure for the matrix element derivation. Rather than matching the eikonal Coulomb-Volkov wave function with the bound state as in the ARM theory to remove the Coulomb singularity, we calculate the matrix element via the saddle-point integration method by time as well as by coordinate, and in this way avoiding the Coulomb singularity. The momentum shift in the photoelectron momentum distribution with respect to the ARM theory due to high-order corrections is analyzed for tunneling and multiphoton regimes. The relation of the quantum corrections to the tunneling delay time is discussed.
Emissions of ammonia and methane from an anaerobic lagoon at a swine animal feeding operation were evaluated five times over a period of two years. The plane-integrated (PI) open-path Fourier transform infrared spectrometry (OP-FTIR) methodology was used to transect the plume at ...
ERIC Educational Resources Information Center
Kingston, Mary; Richards, Curtis; Blank, Rolf; Stonemeier, Jennifer; Trader, Barbara; East, Bill
2014-01-01
In this Issue Brief we discuss the impact that the Schoolwide Integrated Framework for Transformation (SWIFT) has on improving the outcomes of several current federal, state, district, and school education reform initiatives. Federal initiatives include Race to the Top, School Improvement Grants, and Campaign for Grade-Level Reading; Common Core…
Emissions of ammonia and methane from an anaerobic lagoon at a swine animal feeding operation were evaluated five times over a period of two years. The plane-integrated (PI) open-path Fourier transform infrared spectrometry (OP-FTIR) methodology was used to transect the plume at ...
The distinguishable cluster approach from a screened Coulomb formalism.
Kats, Daniel
2016-01-28
The distinguishable cluster doubles equations have been derived starting from an effective screened Coulomb formalism and a particle-hole symmetric formulation of the Fock matrix. A perturbative triples correction to the distinguishable cluster with singles and doubles (DCSD) has been introduced employing the screened integrals. It is shown that the resulting DCSD(T) method is more accurate than DCSD for reaction energies and is less sensitive to the static correlation than coupled cluster with singles and doubles with a perturbative triples correction.
Analytical approach to quasiperiodic beam Coulomb field modeling
NASA Astrophysics Data System (ADS)
Rubtsova, I. D.
2016-09-01
The paper is devoted to modeling of space charge field of quasiperiodic axial- symmetric beam. Particle beam is simulated by charged disks. Two analytical Coulomb field expressions are presented, namely, Fourier-Bessel series and trigonometric polynomial. Both expressions permit the integral representation. It provides the possibility of integro-differential beam dynamics description. Consequently, when beam dynamics optimization problem is considered, it is possible to derive the analytical formula for quality functional gradient and to apply directed optimization methods. In addition, the paper presents the method of testing of space charge simulation code.
Ice limit of Coulomb gauge Yang-Mills theory
Heinzl, T.; Ilderton, A.; Langfeld, K.; Lavelle, M.; McMullan, D.
2008-10-01
In this paper we describe gauge invariant multiquark states generalizing the path integral framework developed by Parrinello, Jona-Lasinio, and Zwanziger to amend the Faddeev-Popov approach. This allows us to produce states such that, in a limit which we call the ice limit, fermions are dressed with glue exclusively from the fundamental modular region associated with Coulomb gauge. The limit can be taken analytically without difficulties, avoiding the Gribov problem. This is illustrated by an unambiguous construction of gauge invariant mesonic states for which we simulate the static quark-antiquark potential.
Pseudospin and spin symmetries in 1+1 dimensions: The case of the Coulomb potential
NASA Astrophysics Data System (ADS)
Castro, Luis B.; de Castro, Antonio S.; Alberto, Pedro
2015-05-01
The problem of fermions in 1+1 dimensions in the presence of a pseudoscalar Coulomb potential plus a mixing of vector and scalar Coulomb potentials which have equal or opposite signs is investigated. We explore all the possible signs of the potentials and discuss their bound-state solutions for fermions and antifermions. We show the relation between spin and pseudospin symmetries by means of charge-conjugation and γ5 chiral transformations. The cases of pure pseudoscalar and mixed vector-scalar potentials, already analyzed in previous works, are obtained as particular cases. The results presented can be extended to 3+1 dimensions.
Some results on the integral transforms and applications to differential equations
Eltayeb, Hassan; Kilicman, Adem
2010-11-11
In this paper we give some remark about the relationship between Sumudu and Laplace transforms, further; for the comparison purpose, we apply both transforms to solve partial differential equations to see the differences and similarities.
a Highly-Integrated Supersonic-Jet Fourier Transform Microwave Spectrometer
NASA Astrophysics Data System (ADS)
Gou, Qian; Feng, Gang; Grabow, Jens-Uwe
2017-06-01
A highly integrated supersonic-jet Fourier-transform microwave spectrometer of coaxially oriented beam-resonator arrangement (COBRA) type, covering 2-20GHz, has been recently built at Chongqing University, China. Built up almost entirely in an NI PXIe chassis, we take the advantage of the NI PXIe-5451 Dual-channel arbitrary waveform generator and the PXIe-5654 RF signal generator to create a spectrometer with wobbling capacity for fast resonator tuning. Based on the I/Q modulation, associate with PXI control and sequence boards built at the Leibniz Universitat Hannover, the design of the spectrometer is much simpler and very compact. The Fabry-Pérot resonator is semi-confocal with a spherical reflector of 630 mm diameter and a radius of 900 mm curvature and one circulator plate reflector of 630 mm diameter. The vacuum is effectuated by a three-stage mechanical (two-stage rotary vane and roots booster) pump at the fore line of a DN630 ISO-F 20000 L/s oil-diffusion pump. The supersonic-jet expansion is pulsed by a general valve Series 9 solenoid valve which is controlled by a general valve IOTA one driver governed by the experiment-sequence generation. First molecular examples to illustrate the performance of the new setup will include OCS and CF_3CHFCl.
Marshall, Deborah A; Burgos-Liz, Lina; Pasupathy, Kalyan S; Padula, William V; IJzerman, Maarten J; Wong, Peter K; Higashi, Mitchell K; Engbers, Jordan; Wiebe, Samuel; Crown, William; Osgood, Nathaniel D
2016-02-01
In the era of the Information Age and personalized medicine, healthcare delivery systems need to be efficient and patient-centred. The health system must be responsive to individual patient choices and preferences about their care, while considering the system consequences. While dynamic simulation modelling (DSM) and big data share characteristics, they present distinct and complementary value in healthcare. Big data and DSM are synergistic-big data offer support to enhance the application of dynamic models, but DSM also can greatly enhance the value conferred by big data. Big data can inform patient-centred care with its high velocity, volume, and variety (the three Vs) over traditional data analytics; however, big data are not sufficient to extract meaningful insights to inform approaches to improve healthcare delivery. DSM can serve as a natural bridge between the wealth of evidence offered by big data and informed decision making as a means of faster, deeper, more consistent learning from that evidence. We discuss the synergies between big data and DSM, practical considerations and challenges, and how integrating big data and DSM can be useful to decision makers to address complex, systemic health economics and outcomes questions and to transform healthcare delivery.
Peeraer, Jef; Van Petegem, Peter
2015-02-01
Over the last two decades, crucial factors for Information and Communication Technology (ICT) in education have improved significantly in Vietnam. Nevertheless, it is clear that, as in other countries, no educational revolution is taking place. We argue that there is a need for a broad dialogue on the future of ICT in education in Vietnam as discussion of ideas about future possibilities can be instrumental in rationalizing and generating educational change. We explore how a group of key players representing the public and private sector as well as development partners in the field look at the future of ICT in education in the country. Following the Delphi method, these key players assessed in different survey rounds the current situation of ICT in education, identified a series of targets and were asked to assess these targets in respect of their importance. The key players reached a consensus that the purpose of technology integration is to achieve learning goals and enhance learning. However, there is more controversy on targets that could potentially transform education practice in Vietnam. We discuss the value of the Delphi technique and argue for increased participation of all involved stakeholders in policy development on ICT in education.
Approximate Coulomb distortion effects in (e,e{sup {prime}}p) reactions
Kim, K.S.; Wright, L.E.
1997-07-01
In this paper we apply a well-tested approximation of electron Coulomb distortion effects to the exclusive reaction (e,e{sup {prime}}p) in the quasielastic region. We compare the approximate treatment of Coulomb distortion effects to the exact distorted wave Born approximation evaluated by means of partial wave analysis to gauge the quality of our approximate treatment. We show that the approximate Mo/ller potential has a plane-wave-like structure and hence permits the separation of the cross section into five terms which depend on bilinear products of transforms of the transition four current elements. These transforms reduce to Fourier transforms when Coulomb distortion is not present, but become modified with the inclusion of Coulomb distortion. We investigate the application of the approximate formalism to a model of {sup 208}Pb(e,e{sup {prime}}p) using Dirac-Hartree single particle wave functions for the ground state and relativistic optical model wave functions for the continuum proton. We show that it is still possible to extract, albeit with some approximation, the various structure functions from the experimentally measured data even for heavy nuclei. {copyright} {ital 1997} {ital The American Physical Society}
Coulomb explosion of “hot spot”
Oreshkin, V. I.; Oreshkin, E. V.; Chaikovsky, S. A.; Artyomov, A. P.
2016-09-15
The study presented in this paper has shown that the generation of hard x rays and high-energy ions, which are detected in pinch implosion experiments, may be associated with the Coulomb explosion of the hot spot that is formed due to the outflow of the material from the pinch cross point. During the process of material outflow, the temperature of the hot spot plasma increases, and conditions arise for the plasma electrons to become continuously accelerated. The runaway of electrons from the hot spot region results in the buildup of positive space charge in this region followed by a Coulomb explosion. The conditions for the hot spot plasma electrons to become continuously accelerated have been revealed, and the estimates have been obtained for the kinetic energy of the ions generated by the Coulomb explosion.
Coulomb wave functions in momentum space
Eremenko, V.; Upadhyay, N. J.; Thompson, I. J.; Elster, Ch.; Nunes, F. M.; Arbanas, G.; Escher, J. E.; Hlophe, L.
2015-10-15
We present an algorithm to calculate non-relativistic partial-wave Coulomb functions in momentum space. The arguments are the Sommerfeld parameter η, the angular momentum l, the asymptotic momentum q and the 'running' momentum p, where both momenta are real. Since the partial-wave Coulomb functions exhibit singular behavior when p → q, different representations of the Legendre functions of the 2nd kind need to be implemented in computing the functions for the values of p close to the singularity and far away from it. The code for the momentum-space Coulomb wave functions is applicable for values of vertical bar eta vertical bar in the range of 10^{-1} to 10, and thus is particularly suited for momentum space calculations of nuclear reactions.
Coulomb wave functions in momentum space
Eremenko, V.; Upadhyay, N. J.; Thompson, I. J.; ...
2015-10-15
We present an algorithm to calculate non-relativistic partial-wave Coulomb functions in momentum space. The arguments are the Sommerfeld parameter η, the angular momentum l, the asymptotic momentum q and the 'running' momentum p, where both momenta are real. Since the partial-wave Coulomb functions exhibit singular behavior when p → q, different representations of the Legendre functions of the 2nd kind need to be implemented in computing the functions for the values of p close to the singularity and far away from it. The code for the momentum-space Coulomb wave functions is applicable for values of vertical bar eta vertical barmore » in the range of 10-1 to 10, and thus is particularly suited for momentum space calculations of nuclear reactions.« less
Counterintuitive Coulomb hole around the bond midplane.
Wang, Jian; Kim, Kwang S; Baerends, Evert Jan
2010-05-28
The Coulomb hole does not have its largest depth around an electron in or near the bond midplane. It splits into two parts, localized on both nuclear sites forming the bond. Even counterintuitive positive values of the "hole" around such a position may be observed. This happens when the Fermi hole is deeper than the total exchange-correlation hole at the reference electron position. This Coulomb "heap" is shown to arise from correlation effects on the one-electron density rather than correlation effects in the pair density. Left-right correlation tends to enhance the effect of the nuclear attraction, contracting the electron density around the nuclear positions and depleting the bond center region. Possible alternative definitions of the Coulomb hole are discussed, including one based on the exact Kohn-Sham exchange hole. Approximate density functional theory methods (generalized gradient approximation) are not accurate enough to realize the advantages of this definition.
Coulomb bound states of strongly interacting photons
Maghrebi, M. F.; Choi, S.; Martin, I.; Firstenberg, O.; Lukin, M. D.; Büchler, H. P.; Gorshkov, A. V.
2015-09-16
We show that two photons coupled to Rydberg states via electromagnetically induced transparency (EIT) can interact via an effective Coulomb potential. The interaction then gives rise to a continuum of two-body bound states. Within the continuum, metastable bound states are distinguished in analogy with quasi-bound states tunneling through a potential barrier. We find multiple branches of metastable bound states whose energy spectrum is governed by the Coulomb problem, thus obtaining a photonic analogue of the hydrogen atom. These states propagate with a negative group velocity in the medium, which allows for a simple preparation and detection scheme, before they slowly decay to pairs of bound Rydberg atoms. As a result, we verify the metastability and backward propagation of these Coulomb bound states with exact numerical simulations.
Coulomb bound states of strongly interacting photons
Maghrebi, M. F.; Gullans, Michael J.; Bienias, P.; ...
2015-09-16
We show that two photons coupled to Rydberg states via electromagnetically induced transparency (EIT) can interact via an effective Coulomb potential. The interaction then gives rise to a continuum of two-body bound states. Within the continuum, metastable bound states are distinguished in analogy with quasi-bound states tunneling through a potential barrier. We find multiple branches of metastable bound states whose energy spectrum is governed by the Coulomb problem, thus obtaining a photonic analogue of the hydrogen atom. These states propagate with a negative group velocity in the medium, which allows for a simple preparation and detection scheme, before they slowlymore » decay to pairs of bound Rydberg atoms. As a result, we verify the metastability and backward propagation of these Coulomb bound states with exact numerical simulations.« less
Screened Coulomb interactions with non-uniform surface charge
NASA Astrophysics Data System (ADS)
Ghosal, Sandip; Sherwood, John D.
2017-03-01
The screened Coulomb interaction between a pair of infinite parallel planes with spatially varying surface charge is considered in the limit of small electrical potentials for arbitrary Debye lengths. A simple expression for the disjoining pressure is derived in terms of a two-dimensional integral in Fourier space. The integral is evaluated for periodic and random charge distributions and the disjoining pressure is expressed as a sum over Fourier-Bloch reciprocal lattice vectors or in terms of an integral involving the autocorrelation function, respectively. The force between planes with a finite area of uniform charge, a model for the DLVO interaction between finite surfaces, is also calculated. It is shown that the overspill of the charge cloud beyond the region immediately between the charged areas results in a reduction of the disjoining pressure, as reported by us recently in the long Debye length limit for planes of finite width.
Three-body Coulomb continuum problem
NASA Astrophysics Data System (ADS)
Berakdar, J.; Briggs, J. S.
1994-06-01
A symmetric representation of the three-body Coulomb continuum wave function as a product of three two-body Coulomb wave functions is modified to allow for three-body effects whereby the Sommerfeld parameter describing the strength of interaction of any two particles is affected by the presence of the third particle. This approach gives excellent agreement with near-threshold absolute (e,2e) ionization cross sections. In particular a recently observed deep minimum in noncoplanar geometry is reproduced for the first time.
Observation of ionic Coulomb blockade in nanopores
NASA Astrophysics Data System (ADS)
Feng, Jiandong; Liu, Ke; Graf, Michael; Dumcenco, Dumitru; Kis, Andras; di Ventra, Massimiliano; Radenovic, Aleksandra
2016-08-01
Emergent behaviour from electron-transport properties is routinely observed in systems with dimensions approaching the nanoscale. However, analogous mesoscopic behaviour resulting from ionic transport has so far not been observed, most probably because of bottlenecks in the controlled fabrication of subnanometre nanopores for use in nanofluidics. Here, we report measurements of ionic transport through a single subnanometre pore junction, and the observation of ionic Coulomb blockade: the ionic counterpart of the electronic Coulomb blockade observed for quantum dots. Our findings demonstrate that nanoscopic, atomically thin pores allow for the exploration of phenomena in ionic transport, and suggest that nanopores may also further our understanding of transport through biological ion channels.
Nonlocal Coulomb drag in Weyl semimetals
NASA Astrophysics Data System (ADS)
Baum, Yuval; Stern, Ady
2017-02-01
Nonlocality is one of the most striking signatures of the topological nature of Weyl semimetals. We propose to probe the nonlocality in these materials via a measurement of a magnetic-field-dependent Coulomb drag between two sheets of graphene which are separated by a three-dimensional slab of Weyl semimetal. We predict a mechanism of Coulomb drag, based on cyclotron orbits that are split between opposite surfaces of the semimetal. In the absence of impurity scattering between different Weyl nodes, this mechanism does not decay with the thickness of the semimetal.
An implicit fast Fourier transform method for integration of the time dependent Schrodinger equation
Riley, M.E.; Ritchie, A.B.
1997-12-31
One finds that the conventional exponentiated split operator procedure is subject to difficulties when solving the time-dependent Schrodinger equation for Coulombic systems. By rearranging the kinetic and potential energy terms in the temporal propagator of the finite difference equations, one can find a propagation algorithm for three dimensions that looks much like the Crank-Nicholson and alternating direction implicit methods for one- and two-space-dimensional partial differential equations. The authors report investigations of this novel implicit split operator procedure. The results look promising for a purely numerical approach to certain electron quantum mechanical problems. A charge exchange calculation is presented as an example of the power of the method.
Repair-dependent cell radiation survival and transformation: an integrated theory.
Sutherland, John C
2014-09-07
The repair-dependent model of cell radiation survival is extended to include radiation-induced transformations. The probability of transformation is presumed to scale with the number of potentially lethal damages that are repaired in a surviving cell or the interactions of such damages. The theory predicts that at doses corresponding to high survival, the transformation frequency is the sum of simple polynomial functions of dose; linear, quadratic, etc, essentially as described in widely used linear-quadratic expressions. At high doses, corresponding to low survival, the ratio of transformed to surviving cells asymptotically approaches an upper limit. The low dose fundamental- and high dose plateau domains are separated by a downwardly concave transition region. Published transformation data for mammalian cells show the high-dose plateaus predicted by the repair-dependent model for both ultraviolet and ionizing radiation. For the neoplastic transformation experiments that were analyzed, the data can be fit with only the repair-dependent quadratic function. At low doses, the transformation frequency is strictly quadratic, but becomes sigmodial over a wider range of doses. Inclusion of data from the transition region in a traditional linear-quadratic analysis of neoplastic transformation frequency data can exaggerate the magnitude of, or create the appearance of, a linear component. Quantitative analysis of survival and transformation data shows good agreement for ultraviolet radiation; the shapes of the transformation components can be predicted from survival data. For ionizing radiations, both neutrons and x-rays, survival data overestimate the transforming ability for low to moderate doses. The presumed cause of this difference is that, unlike UV photons, a single x-ray or neutron may generate more than one lethal damage in a cell, so the distribution of such damages in the population is not accurately described by Poisson statistics. However, the complete
Coulomb string tension, asymptotic string tension, and the gluon chain
Greensite, Jeff; Szczepaniak, Adam P.
2015-02-01
We compute, via numerical simulations, the non-perturbative Coulomb potential and position-space ghost propagator in pure SU(3) gauge theory in Coulomb gauge. We find that that the Coulomb potential scales nicely in accordance with asymptotic freedom, that the Coulomb potential is linear in the infrared, and that the Coulomb string tension is about four times larger than the asymptotic string tension. We explain how it is possible that the asymptotic string tension can be lower than the Coulomb string tension by a factor of four.
Coulomb string tension, asymptotic string tension, and the gluon chain
Greensite, Jeff; Szczepaniak, Adam P.
2015-02-01
We compute, via numerical simulations, the non-perturbative Coulomb potential and position-space ghost propagator in pure SU(3) gauge theory in Coulomb gauge. We find that that the Coulomb potential scales nicely in accordance with asymptotic freedom, that the Coulomb potential is linear in the infrared, and that the Coulomb string tension is about four times larger than the asymptotic string tension. We explain how it is possible that the asymptotic string tension can be lower than the Coulomb string tension by a factor of four.
Sima, Chaotan; Gates, J C; Rogers, H L; Mennea, P L; Holmes, C; Zervas, M N; Smith, P G R
2013-03-01
The monolithically integrated all-optical single-sideband (SSB) filter based on photonic Hilbert transform and planar Bragg gratings is proposed and experimentally demonstrated. An SSB suppression of 12 dB at 6 GHz and sideband switching are achieved via thermal tuning. An X-coupler, photonic Hilbert transformer, flat top reflector, and a micro heater are incorporated in a single silicon-on-silica substrate. The device can be thermally tuned by the micro heater on top of the channel waveguide. The device is fabricated using a combination of direct UV grating writing technology and photolithography.
A Coulomb-Like Off-Shell T-Matrix with the Correct Coulomb Phase Shift
NASA Astrophysics Data System (ADS)
Oryu, Shinsho; Watanabe, Takashi; Hiratsuka, Yasuhisa; Togawa, Yoshio
2017-03-01
We confirm the reliability of the well-known Coulomb renormalization method (CRM). It is found that the CRM is only available for a very-long-range screened Coulomb potential (SCP). However, such an SCP calculation in momentum space is considerably difficult because of the cancelation of significant digits. In contrast to the CRM, we propose a new method by using an on-shell equivalent SCP and the rest term. The two-potential theory with r-space is introduced, which defines fully the off-shell Coulomb amplitude.
NASA Astrophysics Data System (ADS)
Šprlák, Michal; Novák, Pavel
2017-02-01
New spherical integral formulas between components of the second- and third-order gravitational tensors are formulated in this article. First, we review the nomenclature and basic properties of the second- and third-order gravitational tensors. Initial points of mathematical derivations, i.e., the second- and third-order differential operators defined in the spherical local North-oriented reference frame and the analytical solutions of the gradiometric boundary-value problem, are also summarized. Secondly, we apply the third-order differential operators to the analytical solutions of the gradiometric boundary-value problem which gives 30 new integral formulas transforming (1) vertical-vertical, (2) vertical-horizontal and (3) horizontal-horizontal second-order gravitational tensor components onto their third-order counterparts. Using spherical polar coordinates related sub-integral kernels can efficiently be decomposed into azimuthal and isotropic parts. Both spectral and closed forms of the isotropic kernels are provided and their limits are investigated. Thirdly, numerical experiments are performed to test the consistency of the new integral transforms and to investigate properties of the sub-integral kernels. The new mathematical apparatus is valid for any harmonic potential field and may be exploited, e.g., when gravitational/magnetic second- and third-order tensor components become available in the future. The new integral formulas also extend the well-known Meissl diagram and enrich the theoretical apparatus of geodesy.
Benchmark values for molecular three-center integrals arising in the Dirac equation
NASA Astrophysics Data System (ADS)
Baǧcı, A.; Hoggan, P. E.
2015-10-01
Previous papers by the authors report that they obtained compact, arbitrarily accurate expressions for two-center, one- and two-electron relativistic molecular integrals expressed over Slater-type orbitals. In the present study, accuracy limits of expressions given are examined for three-center nuclear attraction integrals, which are one-electron, three-center integrals with no analytically closed-form expression. In this work new molecular auxiliary functions are used. They are obtained via Neumann expansion of the Coulomb interaction. The numerical global adaptive method is used to evaluate these integrals for arbitrary values of orbital parameters and quantum numbers. Several methods, such as Laplace expansion of Coulomb interaction, single-center expansion, and the Fourier transformation method, have previously been used to evaluate these integrals considering the values of principal quantum numbers in the set of positive integer numbers. This study of three-center integrals places no restrictions on quantum numbers in all ranges of orbital parameters.
Benchmark values for molecular three-center integrals arising in the Dirac equation.
Bağcı, A; Hoggan, P E
2015-10-01
Previous papers by the authors report that they obtained compact, arbitrarily accurate expressions for two-center, one- and two-electron relativistic molecular integrals expressed over Slater-type orbitals. In the present study, accuracy limits of expressions given are examined for three-center nuclear attraction integrals, which are one-electron, three-center integrals with no analytically closed-form expression. In this work new molecular auxiliary functions are used. They are obtained via Neumann expansion of the Coulomb interaction. The numerical global adaptive method is used to evaluate these integrals for arbitrary values of orbital parameters and quantum numbers. Several methods, such as Laplace expansion of Coulomb interaction, single-center expansion, and the Fourier transformation method, have previously been used to evaluate these integrals considering the values of principal quantum numbers in the set of positive integer numbers. This study of three-center integrals places no restrictions on quantum numbers in all ranges of orbital parameters.
Effective Coulomb logarithm for one component plasma
NASA Astrophysics Data System (ADS)
Khrapak, Sergey A.
2013-05-01
An expression for the effective Coulomb logarithm in one-component-plasma is proposed, which allows to extend the applicability of the classical formula for the self-diffusion coefficient to the strongly coupled regime. The proposed analytical approximation demonstrates reasonable agreement with previous numerical simulation results. Relevance to weakly screened Yukawa systems (and, in particular, complex plasmas) is discussed.
Bound states of screened coulomb potentials
NASA Astrophysics Data System (ADS)
Dutt, Ranabir; Ray, Aparna; Ray, Pritam P.
1981-05-01
We propose an extension of the Ecker-Weizel approximation to treat the non-zero angular momentum bound states of a class of screened Coulomb potentials. As an illustration of our prescription, we have calculated the discrete energies Enl of the Yukawa potential, which are in excellent agreement with those of Rogers et al.
Coulomb drag between helical Luttinger liquids
NASA Astrophysics Data System (ADS)
Kainaris, N.; Gornyi, I. V.; Levchenko, A.; Polyakov, D. G.
2017-01-01
We theoretically study Coulomb drag between two helical edges with broken spin-rotational symmetry, such as would occur in two capacitively coupled quantum spin Hall insulators. For the helical edges, Coulomb drag is particularly interesting because it specifically probes the inelastic interactions that break the conductance quantization for a single edge. Using the kinetic equation formalism, supplemented by bosonization, we find that the drag resistivity ρD exhibits a nonmonotonic dependence on the temperature T . In the limit of low T ,ρD vanishes with decreasing T as a power law if intraedge interactions are not too strong. This is in stark contrast to Coulomb drag in conventional quantum wires, where ρD diverges at T →0 irrespective of the strength of repulsive interactions. Another unusual property of Coulomb drag between the helical edges concerns higher T for which, unlike in the Luttinger liquid model, drag is mediated by plasmons. The special type of plasmon-mediated drag can be viewed as a distinguishing feature of the helical liquid—because it requires peculiar umklapp scattering only available in the presence of a Dirac point in the electron spectrum.
Molecular Dynamics Simulations of Coulomb Explosion
Bringa, E M
2002-05-17
A swift ion creates a track of electronic excitations in the target material. A net repulsion inside the track can cause a ''Coulomb Explosion'', which can lead to damage and sputtering of the material. Here we report results from molecular-dynamics (MD) simulations of Coulomb explosion for a cylindrical track as a function of charge density and neutralization/quenching time, {tau}. Screening by the free electrons is accounted for using a screened Coulomb potential for the interaction among charges. The yield exhibits a prompt component from the track core and a component, which dominates at higher excitation density, from the heated region produced. For the cases studied, the number of atoms ejected per incident ion, i.e. the sputtering yield Y, is quadratic with charge density along the track as suggested by simple models. Y({tau} = 0.2 Debye periods) is nearly 20% of the yield when there is no neutralization ({tau} {yields} {infinity}). The connections between ''Coulomb explosions'', thermal spikes and measurements of electronic sputtering are discussed.
Effective Coulomb logarithm for one component plasma
Khrapak, Sergey A.
2013-05-15
An expression for the effective Coulomb logarithm in one-component-plasma is proposed, which allows to extend the applicability of the classical formula for the self-diffusion coefficient to the strongly coupled regime. The proposed analytical approximation demonstrates reasonable agreement with previous numerical simulation results. Relevance to weakly screened Yukawa systems (and, in particular, complex plasmas) is discussed.
Coulomb's Electrical Measurements. Experiment No. 14.
ERIC Educational Resources Information Center
Devons, Samuel
Presented is information related to the life and work of Charles Coulomb as well as detailed notes of his measurements of the distribution of electricity on conductors. The two methods that he used (the large torsion balance, and the timing of "force" oscillations) are described. (SA)
The Pioneer Anomaly as a Coulomb Attraction
NASA Astrophysics Data System (ADS)
Morris, Steven
2016-06-01
The anomalous acceleration of the Pioneer 10 and Pioneer 11 spacecraft can be explained as a Coulomb attraction between the positively-charged Solar System (due to cosmic rays) and the negatively-charged spacecraft (due to alpha-particle emission from the radioisotope thermoelectric generators).
Coulomb Logarithm, Version 1.0
Singleton, Robert
2016-11-23
Clog is a library of charged particle stopping powers and related Coulomb logarithm processes in a plasma. The stopping power is a particularly useful quantity for plasma physics, as it measures the energy loss of per unit length of charged particle as it traverses a plasma. Clog's primary stopping power is the BPS (Brown-Preston-Singleton) theory.
USDA-ARS?s Scientific Manuscript database
The species Campylobacter jejuni displays huge genetic diversity, and is naturally competent for DNA uptake. Nevertheless, not every strain is able to acquire foreign DNA since nonnaturally transformable strains do exist. Previously we showed that many nonnaturally transformable C. jejuni strains ex...
Remote Spacecraft Attitude Control by Coulomb Charging
NASA Astrophysics Data System (ADS)
Stevenson, Daan
The possibility of inter-spacecraft collisions is a serious concern at Geosynchronous altitudes, where many high-value assets operate in proximity to countless debris objects whose orbits experience no natural means of decay. The ability to rendezvous with these derelict satellites would enable active debris removal by servicing or repositioning missions, but docking procedures are generally inhibited by the large rotational momenta of uncontrolled satellites. Therefore, a contactless means of reducing the rotation rate of objects in the space environment is desired. This dissertation investigates the viability of Coulomb charging to achieve such remote spacecraft attitude control. If a servicing craft imposes absolute electric potentials on a nearby nonspherical debris object, it will impart electrostatic torques that can be used to gradually arrest the object's rotation. In order to simulate the relative motion of charged spacecraft with complex geometries, accurate but rapid knowledge of the Coulomb interactions is required. To this end, a new electrostatic force model called the Multi-Sphere Method (MSM) is developed. All aspects of the Coulomb de-spin concept are extensively analyzed and simulated using a system with simplified geometries and one dimensional rotation. First, appropriate control algorithms are developed to ensure that the nonlinear Coulomb torques arrest the rotation with guaranteed stability. Moreover, the complex interaction of the spacecraft with the plasma environment and charge control beams is modeled to determine what hardware requirements are necessary to achieve the desired electric potential levels. Lastly, the attitude dynamics and feedback control development is validated experimentally using a scaled down terrestrial testbed. High voltage power supplies control the potential on two nearby conductors, a stationary sphere and a freely rotating cylinder. The nonlinear feedback control algorithms developed above are implemented to
NASA Astrophysics Data System (ADS)
Marikhin, V. G.
2016-12-01
We construct a three-dimensional octahedral lattice of Bäcklund transformations of integrable cases of the Davey-Stewartson system. At the lattice sites, we arrange functions, which, on one hand, are used to define the dynamical variables of the Davey-Stewartson system and, on the other hand, are connected by bilinear relations of the Hirota type. One of the lattice equations is a purely discrete six-point equation that coincides with the famous Hirota equation.
NASA Astrophysics Data System (ADS)
Liu, Hanze; Xin, Xiangpeng; Wang, Zenggui; Liu, Xiqiang
2017-03-01
This paper is concerned with the Bäcklund transformations (BTs) of the nonlinear evolution equations (NLEEs). Based on the homogeneous balance principle (HBP), the existence of the BT of the generalized Burgers'-KdV (B-KdV) equation is classified, then the BTs of the nonlinear equations are given. In general, the method can be used to construct BTs of the nonlinear evolution equations in polynomial form. Furthermore, the integrability and exact explicit solutions to the nonlinear equations are investigated.
Cotunneling Drag Effect in Coulomb-Coupled Quantum Dots
NASA Astrophysics Data System (ADS)
Keller, A. J.; Lim, J. S.; Sánchez, David; López, Rosa; Amasha, S.; Katine, J. A.; Shtrikman, Hadas; Goldhaber-Gordon, D.
2016-08-01
In Coulomb drag, a current flowing in one conductor can induce a voltage across an adjacent conductor via the Coulomb interaction. The mechanisms yielding drag effects are not always understood, even though drag effects are sufficiently general to be seen in many low-dimensional systems. In this Letter, we observe Coulomb drag in a Coulomb-coupled double quantum dot and, through both experimental and theoretical arguments, identify cotunneling as essential to obtaining a correct qualitative understanding of the drag behavior.
Quantum mechanics on phase space and the Coulomb potential
NASA Astrophysics Data System (ADS)
Campos, P.; Martins, M. G. R.; Vianna, J. D. M.
2017-04-01
Symplectic quantum mechanics (SMQ) makes possible to derive the Wigner function without the use of the Liouville-von Neumann equation. In this formulation of the quantum theory the Galilei Lie algebra is constructed using the Weyl (or star) product with Q ˆ = q ⋆ = q +iħ/2∂p , P ˆ = p ⋆ = p -iħ/2∂q, and the Schrödinger equation is rewritten in phase space; in consequence physical applications involving the Coulomb potential present some specific difficulties. Within this context, in order to treat the Schrödinger equation in phase space, a procedure based on the Levi-Civita (or Bohlin) transformation is presented and applied to two-dimensional (2D) hydrogen atom. Amplitudes of probability in phase space and the correspondent Wigner quasi-distribution functions are derived and discussed.
Measurement of the 92,93,94,100Mo(γ,n) reactions by Coulomb Dissociation
NASA Astrophysics Data System (ADS)
Göbel, K.; Adrich, P.; Altstadt, S.; Alvarez-Pol, H.; Aksouh, F.; Aumann, T.; Babilon, M.; Behr, K.-H.; Benlliure, J.; Berg, T.; Böhmer, M.; Boretzky, K.; Brünle, A.; Beyer, R.; Casarejos, E.; Chartier, M.; Cortina-Gil, D.; Chatillon, A.; Datta Pramanik, U.; Deveaux, L.; Elvers, M.; Elze, T. W.; Emling, H.; Erhard, M.; Ershova; Fernandez-Dominguez, B.; Geissel, H.; Górska, M.; Heftrich, T.; Heil, M.; Hellstroem, M.; Ickert, G.; Johansson, H.; Junghans, A. R.; Käppeler, F.; Kiselev, O.; Klimkiewicz, A.; Kratz, J. V.; Kulessa, R.; Kurz, N.; Labiche, M.; Langer, C.; Le Bleis, T.; Lemmon, R.; Lindenberg, K.; Litvinov, Y. A.; Maierbeck, P.; Movsesyan, A.; Müller, S.; Nilsson, T.; Nociforo, C.; Paar, N.; Palit, R.; Paschalis, S.; Plag, R.; Prokopowicz, W.; Reifarth, R.; Rossi, D. M.; Schnorrenberger, L.; Simon, H.; Sonnabend, K.; Sümmerer, K.; Surówka, G.; Vretenar, D.; Wagner, A.; Walter, S.; Waluś, W.; Wamers, F.; Weick, H.; Weigand, M.; Winckler, N.; Winkler, M.; Zilges, A.
2016-01-01
The Coulomb Dissociation (CD) cross sections of the stable isotopes 92,94,100Mo and of the unstable isotope 93Mo were measured at the LAND/R3B setup at GSI Helmholtzzentrum für Schwerionenforschung in Darmstadt, Germany. Experimental data on these isotopes may help to explain the problem of the underproduction of 92,94Mo and 96,98Ru in the models of p-process nucleosynthesis. The CD cross sections obtained for the stable Mo isotopes are in good agreement with experiments performed with real photons, thus validating the method of Coulomb Dissociation. The result for the reaction 93Mo(γ,n) is especially important since the corresponding cross section has not been measured before. A preliminary integral Coulomb Dissociation cross section of the 94Mo(γ,n) reaction is presented. Further analysis will complete the experimental database for the (γ,n) production chain of the p-isotopes of molybdenum.
DNA Integrity and Shock Wave Transformation Efficiency of Bacteria and Fungi
NASA Astrophysics Data System (ADS)
Loske, Achim M.; Campos-Guillén, Juan; Fernández, Francisco; Pastrana, Xóchitl; Magaña-Ortíz, Denis; Coconi-Linares, Nancy; Ortíz-Vázquez, Elizabeth; Gómez-Lim, Miguel
Delivery of DNA into bacteria and fungi is essential in medicine and biotechnology to produce metabolites, enzymes, antibiotics and proteins. So far, protocols to genetically transform bacteria and fungi are inefficient and have low reproducibility.
Absence of exponential clustering in quantum Coulomb fluids
NASA Astrophysics Data System (ADS)
Alastuey, A.; Martin, Ph. A.
1989-12-01
We show that the quantum corrections to the classical correlations of a Coulomb fluid do not decay exponentially fast for all values of the thermodynamical parameters. Specifically, the ħ4 term in the Wigner-Kirkwood expansion of the equilibrium charge-charge correlations of the quantum one-component plasma is found to decay like ||r||-10. More generally, using functional integration, we present a diagrammatic representation of the ħ expansion of the correlations in a multicomponent fluid with a locally regularized Coulomb potential and Maxwell-Boltzmann statistics. The ħ2n terms are found to decay algebraically for all n>=2. Furthermore, an analysis of the hierarchy equations for the correlations provides upper bounds that are compatible with the findings of the perturbative expansion. Except for the monopole, all higher-order multipole sum rules do not hold, in general, in the quantum system. This violation of the multipole sum rules as well as the related algebraic tails are due to the intrinsic quantum fluctuations that prevent a perfect organization of the screening clouds. This phenomenon is illustrated in a simpler model where the large-distance correlations between two quantum particles embedded in a classical plasma can be exactly computed.
Mahairas, G G; Minion, F C
1989-01-01
The transposons Tn916 and Tn4001 and a series of integrating plasmids derived from their antibiotic resistance genes were used to examine polyethylene glycol-mediated transformation of Mycoplasma pulmonis. Under optimal conditions, Tn916 and Tn4001 could be introduced into M. pulmonis at frequencies of 1 x 10(-6) and 5 x 10(-5) per CFU, respectively. Integrating plasmids were constructed with the cloned antibiotic resistance determinants of Tn916 and Tn4001, a pMB1-derived plasmid replicon, and mycoplasmal chromosomal DNA and were used to examine recombinational events after transformation into M. pulmonis. Under optimal conditions, chromosomal integrations could be recovered at a frequency of 1 x 10(-4) to 1 x 10(-6) per CFU, depending on the size and nature of the chromosomal insert and the parental plasmid. Integrated plasmids were stable in the absence of selection and could be rescued in Escherichia coli along with adjacent mycoplasma DNA. These studies provide the first direct evidence of a recombination system in the Mollicutes and describe the first E. coli-M. pulmonis shuttle vectors. Images PMID:2539351
Multicenter molecular integrals for Slater orbitals of higher principal quantum numbers
NASA Technical Reports Server (NTRS)
Tai, H.
1989-01-01
As was shown earlier by Tai (1979), by using the Fourier-transform technique and properly coupling a pair of two-center exchange integrals, the multicenter molecular integrals can be cast into a simple expression upon which numerical procedures can be directly applied. In this paper, the procedure of Tai is extended to integrals involving orbitals with arbitrarily higher principal quantum number. The derivation is outlined, and the explicit expressions are presented for a three-center nuclear attraction integral and a four-center two-electron Coulomb repulsion integral of arbitrary higher states.
Multicenter molecular integrals for Slater orbitals of higher principal quantum numbers
NASA Technical Reports Server (NTRS)
Tai, H.
1989-01-01
As was shown earlier by Tai (1979), by using the Fourier-transform technique and properly coupling a pair of two-center exchange integrals, the multicenter molecular integrals can be cast into a simple expression upon which numerical procedures can be directly applied. In this paper, the procedure of Tai is extended to integrals involving orbitals with arbitrarily higher principal quantum number. The derivation is outlined, and the explicit expressions are presented for a three-center nuclear attraction integral and a four-center two-electron Coulomb repulsion integral of arbitrary higher states.
Coulomb Bound States of Strongly Interacting Photons
NASA Astrophysics Data System (ADS)
Maghrebi, M. F.; Gullans, M. J.; Bienias, P.; Choi, S.; Martin, I.; Firstenberg, O.; Lukin, M. D.; Büchler, H. P.; Gorshkov, A. V.
2015-09-01
We show that two photons coupled to Rydberg states via electromagnetically induced transparency can interact via an effective Coulomb potential. This interaction gives rise to a continuum of two-body bound states. Within the continuum, metastable bound states are distinguished in analogy with quasibound states tunneling through a potential barrier. We find multiple branches of metastable bound states whose energy spectrum is governed by the Coulomb potential, thus obtaining a photonic analogue of the hydrogen atom. Under certain conditions, the wave function resembles that of a diatomic molecule in which the two polaritons are separated by a finite "bond length." These states propagate with a negative group velocity in the medium, allowing for a simple preparation and detection scheme, before they slowly decay to pairs of bound Rydberg atoms.
Coulomb crystallization of highly charged ions.
Schmöger, L; Versolato, O O; Schwarz, M; Kohnen, M; Windberger, A; Piest, B; Feuchtenbeiner, S; Pedregosa-Gutierrez, J; Leopold, T; Micke, P; Hansen, A K; Baumann, T M; Drewsen, M; Ullrich, J; Schmidt, P O; López-Urrutia, J R Crespo
2015-03-13
Control over the motional degrees of freedom of atoms, ions, and molecules in a field-free environment enables unrivalled measurement accuracies but has yet to be applied to highly charged ions (HCIs), which are of particular interest to future atomic clock designs and searches for physics beyond the Standard Model. Here, we report on the Coulomb crystallization of HCIs (specifically (40)Ar(13+)) produced in an electron beam ion trap and retrapped in a cryogenic linear radiofrequency trap by means of sympathetic motional cooling through Coulomb interaction with a directly laser-cooled ensemble of Be(+) ions. We also demonstrate cooling of a single Ar(13+) ion by a single Be(+) ion-the prerequisite for quantum logic spectroscopy with a potential 10(-19) accuracy level. Achieving a seven-orders-of-magnitude decrease in HCI temperature starting at megakelvin down to the millikelvin range removes the major obstacle for HCI investigation with high-precision laser spectroscopy.
Coulomb edge effects in graphene nanoribbons
NASA Astrophysics Data System (ADS)
Jaskolski, W.; Ayuela, A.
2014-10-01
Coulomb effects in graphene nanoribbons with arbitrary edges are investigated with the use of a mean-field Hubbard model. It was recently shown that chiral ribbons with minimal edges, characterized by the translation vector (n,m), have a similar structure of bands localized around the Fermi energy as pure zigzag ribbons (n-m,0). Here we show that these flat bands in both ribbon cases differ in detail due to the perturbation induced by armchair edge nodes. For chiral ribbons the edge bands split at the zone boundary, where the corresponding bands of (n-m,0) zigzag ribbons are degenerate. Coulomb interactions enhance strongly this splitting and at the same time they bring spin into play. We modify each edge keeping global sublattice balance to find that spin degeneracy can be partially lifted. The breaking of spin-degeneracy depends on the asymmetry between the edges and in some cases leads to spin-polarized currents.
Coulomb impurities in two-dimensional topological insulators
NASA Astrophysics Data System (ADS)
Zhu, Jia-Lin; Li, Guo; Yang, Ning
2017-03-01
Introducing a powerful method, we obtain the exact solutions for a Coulomb impurity in two-dimensional infinite and finite topological insulators. The level order and zero-energy degeneracy of the spectra are found to be quite different between topological trivial and nontrivial phases. For quantum dots of topological insulator, the variation of the edge and Coulomb states with dot size, Coulomb potential, and magnetic field are clearly shown. It is found that for small dots the edge states can be strongly coupled with the Coulomb states and for large dots the edge states are insensitive to the Coulomb fields but sensitive to the magnetic fields.
The scattering of the screened Coulomb potential
NASA Astrophysics Data System (ADS)
Cao, Xin-Wei; Chen, Wen-Li; Li, Yuan-Yuan; Wei, Gao-Feng
2014-08-01
We study the scattering states of the screened Coulomb potential in the nonrelativistic frame. The explicitly calculation formula of phase shift is derived and the normalized radial wave functions of scattering states on the ^{\\prime} k/2\\pi scale^{\\prime} are presented. By studying analytical properties of scattering amplitude the screening effects on bound states are discussed numerically. It is shown that the screening effects increase with increasing screened parameter, especially for large quantum states.
Generalized oscillator strength and Coulomb excitation
NASA Astrophysics Data System (ADS)
Chidichimo, Marita C.; Thorsley, Michael D.
2003-02-01
Coulomb interaction is characterized by two nondimensional fundamental quantities: the Sommerfeld parameter η and the adiabaticity parameter ξ=ηf-ηi. In this different approach, we choose these variables to describe the behavior of the generalized oscillator strength (GOS). The expression we obtain is valid for scattering of electrons, positrons, and nuclei by arbitrary targets. We present asymptotic expansions, in the quantal and semiclassical approximation, of the electric dipole GOS.
Ultrashort pulses in graphene with Coulomb impurities
NASA Astrophysics Data System (ADS)
Konobeeva, N. N.; Belonenko, M. B.
2016-06-01
We have investigated the propagation of an electromagnetic field in graphene with impurities, including the two-dimensional case. The spectrum of electrons for the graphene subsystem is taken from a model that takes into account Coulomb impurities. Based on Maxwell's equations, we have obtained an effective equation for the vector potential of the electromagnetic field. It has been revealed that the pulse shape depends on free parameters.
Coulomb collision effects on linear Landau damping
Callen, J. D.
2014-05-15
Coulomb collisions at rate ν produce slightly probabilistic rather than fully deterministic charged particle trajectories in weakly collisional plasmas. Their diffusive velocity scattering effects on the response to a wave yield an effective collision rate ν{sub eff} ≫ ν and a narrow dissipative boundary layer for particles with velocities near the wave phase velocity. These dissipative effects produce temporal irreversibility for times t ≳ 1/ν{sub eff} during Landau damping of a small amplitude Langmuir wave.
McPherson, Marla C; Cheng, Hans H; Delany, Mary E
2016-11-04
Marek's disease (MD) is a lymphotropic and oncogenic disease of chickens that can lead to death in susceptible and unvaccinated host birds. The causative pathogen, MD virus (MDV), a highly oncogenic alphaherpesvirus, integrates into host genome near the telomeres. MD occurrence is controlled across the globe by biosecurity, selective breeding for enhanced MD genetic resistance, and widespread vaccination of flocks using attenuated serotype 1 MDV or other serotypes. Despite over 40 years of usage, the specific mechanism(s) of MD vaccine-related immunity and anti-tumor effects are not known. Here we investigated the cytogenetic interactions of commonly used MD vaccine strains of all three serotypes (HVT, SB-1, and Rispens) with the host to determine if all were equally capable of host genome integration. We also studied the dynamic profiles of chromosomal association and integration of the three vaccine strains, a first for MD vaccine research. Our cytogenetic data provide evidence that all three MD vaccine strains tested integrate in the chicken host genome as early as 1 day after vaccination similar to oncogenic strains. However, a specific, transformation-associated virus-host phenotype observed for oncogenic viruses is not established. Our results collectively provide an updated model of MD vaccine-host genome interaction and an improved understanding of the possible mechanisms of vaccinal immunity. Physical integration of the oncogenic MDV genome into host chromosomes along with cessation of viral replication appears to have joint signification in MDV's ability to induce oncogenic transformation. Whereas for MD vaccine serotypes, a sustained viral replication stage and lack of the chromosome-integrated only stage were shared traits during early infection.
Thermoelectrics with Coulomb-coupled quantum dots
NASA Astrophysics Data System (ADS)
Thierschmann, Holger; Sánchez, Rafael; Sothmann, Björn; Buhmann, Hartmut; Molenkamp, Laurens W.
2016-12-01
In this article we review the thermoelectric properties of three terminal devices with Coulomb-coupled quantum dots (QDs) as observed in recent experiments [1,2]. The system we consider consists of two Coulomb-blockade QDs, one of which can exchange electrons with only a single reservoir (heat reservoir), while the other dot is tunnel coupled with two reservoirs at a lower temperature (conductor). The heat reservoir and the conductor interact only via the Coulomb coupling of the quantum dots. It has been found that two regimes have to be considered. In the first one, the heat flow between the two systems is small. In this regime, thermally driven occupation fluctuations of the hot QD modify the transport properties of the conductor system. This leads to an effect called thermal gating. Experiments have shown how this can be used to control charge flow in the conductor by means of temperature in a remote reservoir. We further substantiate the observations with model calculations, and implications for the realisation of an all-thermal transistor are discussed. In the second regime, the heat flow between the two systems is relevant. Here the system works as a nanoscale heat engine, as proposed recently (Sánchez and Büttiker [3]). We review the conceptual idea, its experimental realisation and the novel features arising in this new kind of thermoelectric device such as decoupling of heat and charge flow.
Dynamics of Coulombic and gravitational periodic systems
NASA Astrophysics Data System (ADS)
Kumar, Pankaj; Miller, Bruce N.
2016-04-01
We study the dynamics and the phase-space structures of Coulombic and self-gravitating versions of the classical one-dimensional three-body system with periodic boundary conditions. We demonstrate that such a three-body system may be reduced isomorphically to a spatially periodic system of a single particle experiencing a two-dimensional potential on a rhombic plane. For the case of both Coulombic and gravitational versions, exact expressions of the Hamiltonian have been derived in rhombic coordinates. We simulate the phase-space evolution through an event-driven algorithm that utilizes analytic solutions to the equations of motion. The simulation results show that the motion exhibits chaotic, quasiperiodic, and periodic behaviors in segmented regions of the phase space. While there is no evidence of global chaos in either the Coulombic or the gravitational system, the former exhibits a transition from a completely nonchaotic phase space at low energies to a mixed behavior. Gradual yet striking transitions from mild to intense chaos are indicated with changing energy, a behavior that differentiates the spatially periodic systems studied in this Rapid Communication from the well-understood free-boundary versions of the three-body problem. Our treatment of the three-body systems opens avenues for analysis of the dynamical properties exhibited by spatially periodic versions of various classes of systems studied in plasma and gravitational physics as well as in cosmology.
Integrated Deployment Model: A Comprehensive Approach to Transforming the Energy Economy
Werner, M.
2010-11-01
This paper describes the Integrated Deployment model to accelerate market adoption of alternative energy solutions to power homes, businesses, and vehicles through a comprehensive and aggressive approach.
Koufogiannis, E T; Sgouros, N P; Sangriotis, M S
2011-12-01
In most integral image analysis and processing tasks, accurate knowledge of the internal image structure is required. In this paper we present a robust framework for the accurate rectification of perspectively distorted integral images based on multiple line segment detection. The use of multiple line segments increases the overall fault tolerance of our framework providing strong statistical support for the rectification process. The proposed framework is used for the automatic rectification, metric correction, and rotation of distorted integral images. The performance of our framework is assessed over a number of integral images with varying scene complexity and noise levels.
Muniraj, Inbarasan; Guo, Changliang; Lee, Byung-Geun; Sheridan, John T
2015-06-15
We present a method of securing multispectral 3D photon-counted integral imaging (PCII) using classical Hartley Transform (HT) based encryption by employing optical interferometry. This method has the simultaneous advantages of minimizing complexity by eliminating the need for holography recording and addresses the phase sensitivity problem encountered when using digital cameras. These together with single-channel multispectral 3D data compactness, the inherent properties of the classical photon counting detection model, i.e. sparse sensing and the capability for nonlinear transformation, permits better authentication of the retrieved 3D scene at various depth cues. Furthermore, the proposed technique works for both spatially and temporally incoherent illumination. To validate the proposed technique simulations were carried out for both the 2D and 3D cases. Experimental data is processed and the results support the feasibility of the encryption method.
ERIC Educational Resources Information Center
Sahin Izmirli, Özden; Kabakçi Yurdakul, Isil
2014-01-01
An examination of prospective teachers' information and communication technology (ICT) integration skills development in an undergraduate program indicated that the only course available to practice these skills was the teaching practice course. However, the practice and development of these ICT integration skills in the teaching practice course…
Klaseboer, Evert; Sepehrirahnama, Shahrokh; Chan, Derek Y C
2017-08-01
The general space-time evolution of the scattering of an incident acoustic plane wave pulse by an arbitrary configuration of targets is treated by employing a recently developed non-singular boundary integral method to solve the Helmholtz equation in the frequency domain from which the space-time solution of the wave equation is obtained using the fast Fourier transform. The non-singular boundary integral solution can enforce the radiation boundary condition at infinity exactly and can account for multiple scattering effects at all spacings between scatterers without adverse effects on the numerical precision. More generally, the absence of singular kernels in the non-singular integral equation confers high numerical stability and precision for smaller numbers of degrees of freedom. The use of fast Fourier transform to obtain the time dependence is not constrained to discrete time steps and is particularly efficient for studying the response to different incident pulses by the same configuration of scatterers. The precision that can be attained using a smaller number of Fourier components is also quantified.
Transforming Pedagogies: Integrating 21st Century Skills and Web 2.0 Technology
ERIC Educational Resources Information Center
Tucker, Shelia Y.
2014-01-01
According to (P21), Partnership for 21st Century Skills (n.d.), unless the gap is bridged between how students learn and how they live, today's education system will face irrelevance. The way people work and live has been transformed by demographic, economic, political, technological, and informational forces. Schools must adapt to these…
A DNase encoded by integrated element CJIE1 inhibits natural transformation of Campylobacter jejuni
USDA-ARS?s Scientific Manuscript database
The species Campylobacter jejuni (C. jejuni) is considered naturally competent for DNA uptake and displays strong genetic diversity. Yet, non-transformable strains and several relatively stable clonal lineages exist. In the present study, the molecular mechanism responsible for the non-transformabil...
Transformative Experience: An Integrative Construct in the Spirit of Deweyan Pragmatism
ERIC Educational Resources Information Center
Pugh, Kevin J.
2011-01-01
A sentiment held by Dewey and shared by other educators is that learning should enrich and expand everyday experience. However, this goal has not been a focus of research. In this article, I propose "transformative experience" as a construct capable of reflecting this goal and functioning as an empirical research construct. I discuss the…
ERIC Educational Resources Information Center
Dirckinck-Holmfeld, Lone; Lorentsen, Annette
2003-01-01
The article focuses on the use of information and communication technology (ICT) for strengthening and transforming university practice in line with the social and technological conditions of the new ideas for "interactive" universities. The purpose is to use ICT as a change-agent in order to establish new practices--new pedagogical…
Quantum Coulomb systems: some exact results in the atomic limit
NASA Astrophysics Data System (ADS)
Ballenegger, V.; Martin, Ph. A.
2002-04-01
We review a number of exact results concerning the recombined electron-proton gas. The recombination problem can be formulated in precise terms in the atomic limit. In this limit one lets the density and the temperature tend to zero in a coupled way so that the resulting energy-entropy balance favors the formation of certain chemical species. This enables to develop a clear understanding of the dielectric versus conducting behavior in the system. In particular, we give a first principle derivation of the dielectric constant of the dilute atomic gas without presupposing the existence of atoms. The analysis relies on the path integral representation of the Coulomb gas together with Mayer diagrammatic techniques.
NASA Astrophysics Data System (ADS)
Santos, J. C.; Rubini, J.; Silva, L. P. C.; Caetano, R. E.
2015-09-01
The use of two electro-optical modulators linked in series, one for sensing and one for recovering signals, was formerly presented by some of the authors as a solution for interrogation of optical fiber sensor systems based on WLI method. A key feature required from such systems is that half-wave voltage (Vπ) of recovering modulator must be as small as possible. Aiming at meeting this requirement, in this paper it is presented the use of an unbalanced Michelson Interferometer implemented using an integrated optics component as recover interferometer in an optical voltage transformer intended for high voltage measurements.
Rolled-up transformer structure for a radiofrequency integrated circuit (RFIC)
Li, Xiuling; Huang, Wen
2015-01-27
A rolled-up transformer structure comprises a multilayer sheet having a rolled configuration comprising multiple turns about a longitudinal axis. The multilayer sheet comprises more than one conductive pattern layer on a strain-relieved layer, including a first conductive film and a second conductive film separated from the first conductive film in a thickness direction. The first conductive film comprises an even number of primary conductive strips, where each primary conductive strip has a length extending in the rolling direction, and the second conductive film comprises an even number of secondary conductive strips, where each secondary conductive strip has a length extending in the rolling direction. In the rolled configuration, turns of the primary conductive strips and turns of the secondary conductive strips wrap around the longitudinal axis. The primary conductive strips serve as a primary winding and the secondary conductive strips serve as a secondary winding of the rolled-up transformer structure.
Rolled-up transformer structure for a radiofrequency integrated circuit (RFIC)
Li, Xiuling; Huang, Wen
2016-05-03
A rolled-up transformer structure comprises a multilayer sheet having a rolled configuration comprising multiple turns about a longitudinal axis. The multilayer sheet comprises more than one conductive pattern layer on a strain-relieved layer, including a first conductive film and a second conductive film separated from the first conductive film in a thickness direction. The first conductive film comprises an even number of primary conductive strips, where each primary conductive strip has a length extending in the rolling direction, and the second conductive film comprises an even number of secondary conductive strips, where each secondary conductive strip has a length extending in the rolling direction. In the rolled configuration, turns of the primary conductive strips and turns of the secondary conductive strips wrap around the longitudinal axis. The primary conductive strips serve as a primary winding and the secondary conductive strips serve as a secondary winding of the rolled-up transformer structure.
Bazargani, Hamed Pishvai; Burla, Maurizio; Chrostowski, Lukas; Azaña, José
2016-11-01
We experimentally demonstrate high-performance integer and fractional-order photonic Hilbert transformers based on laterally apodized Bragg gratings in a silicon-on-insulator technology platform. The sub-millimeter-long gratings have been fabricated using single-etch electron beam lithography, and the resulting HT devices offer operation bandwidths approaching the THz range, with time-bandwidth products between 10 and 20.
Militello, Kevin T; Chang, Ming-Mei; Simon, Robert D; Lazatin, Justine C
2016-01-01
The ability of students to understand the relationship between genotype and phenotype, and the mechanisms by which genotypes and phenotypes can change is essential for students studying genetics. To this end, we have developed a four-week laboratory called Blue Genes, which is designed to help novice students discriminate between two mechanisms by which the genetic material can be altered: genetic transformation and gene mutation. In the first week of the laboratory, students incubate a plasmid DNA with calcium chloride-treated Escherichia coli JM109 cells and observe a phenotype change from ampicillin sensitive to ampicillin resistant and from white color to blue color on plates containing 5-bromo-4-chloro-3-indolyl-β-D-galactopyranoside (X-gal) and isopropyl β-D-thiogalactopyranoside (IPTG). Over the course of the next three weeks, students use a battery of approaches including plasmid DNA isolation experiments, restriction maps, and PCR to differentiate between mutation and transformation. The students ultimately come to the conclusion that the changes in phenotypes are due to genetic transformation and not mutation based on the evidence generated over the four-week period. Pre-laboratory tests and post-laboratory tests indicate that this set of exercises is successful in helping students differentiate between transformation and mutation. The laboratory is designed for underclassmen and is a good prerequisite for an apprentice-based research opportunity, although it is not designed as a class based research experience. Potential modifications and future directions of the laboratory based upon student experiences and assessment are presented.
Weinstein, Lara Carson; Henwood, Benjamin F.; Cody, Julianne W.; Jordan, Maria; Lelar, Rebecca
2014-01-01
Despite the high rate of co-occurring medical conditions experienced by individuals receiving assertive community treatment (ACT), this comprehensive service model continues to be considered primarily a mental health intervention. Without compromising fidelity to the model, ACT can serve as an ideal platform from which to provide both primary and behavioral health care to those with complex service needs. Using a case example, this article considers the transformation of the ACT mental health care model into an integrated health care delivery system through establishing nursing and primary care partnerships. Specifically, by expanding and explicitly redefining the role of the ACT nurse, well-developed care models, such as Guided Care, can provide additional guidelines and training to ACT nurses who are uniquely trained and oriented to serve as the leader and coordinator of health integration efforts. PMID:21659296
Fierro, Francisco; Laich, Federico; García-Rico, Ramón O; Martín, Juan F
2004-01-15
Penicillium nalgiovense is a filamentous fungus that is acquiring increasing biotechnological importance in the food industry due to its widespread use as starter culture for cured and fermented meat products. Strains of P. nalgiovense can be improved by genetic modification to remove the production of penicillin and other potentially hazardous secondary metabolites, to improve its capacity to control the growth of undesirable fungi and bacteria on the meat product, and other factors that contribute to the ripening of the product in order to get safer and better quality foods. Genetic manipulation of P. nalgiovense has been limited by the lack of molecular genetics tools that were available for this fungus, particularly for "self-cloning" avoiding the use of exogenous DNAs. In this article we describe a series of vectors, selectable markers and transformation methods that can be used for efficient transformation of P. nalgiovense, gene cloning and expression. A uridine auxotrophic P. nalgiovense mutant with an inactive pyrG gene has been isolated. The P. nalgiovense wild-type pyrG gene was cloned and sequenced, and vectors carrying the gene were shown to complement the pyrG mutant. Autonomously replicating plasmids carrying the AMA1 region from Aspergillus nidulans transformed P. nalgiovense very efficiently; these plasmids were shown to be maintained as stable extrachromosomal elements in P. nalgiovense and could be rescued in Escherichia coli. The mitotic stability of self-replicative AMA1 plasmids in P. nalgiovense was higher than that reported for Penicillium chrysogenum.
NASA Astrophysics Data System (ADS)
Mohammadi, Vahid; Chenaghlou, Alireza
2017-09-01
The two-dimensional Dirac equation with spin and pseudo-spin symmetries is investigated in the presence of the maximally superintegrable potentials. The integrals of motion and the quadratic algebras of the superintegrable quantum E3‧, anisotropic oscillator and the Holt potentials are studied. The corresponding Casimir operators and the structure functions of the mentioned superintegrable systems are found. Also, we obtain the relativistic energy spectra of the corresponding superintegrable systems. Finally, the relativistic energy eigenvalues of the generalized Yang-Coulomb monopole (YCM) superintegrable system (a SU(2) non-Abelian monopole) are calculated by the energy spectrum of the eight-dimensional oscillator which is dual to the former system by Hurwitz transformation.
NASA Astrophysics Data System (ADS)
Scherer, Philipp O. J.
Fourier transformation is a very important tool for signal analysis but also helpful to simplify the solution of differential equations or the calculation of convolution integrals. An important numerical method is the discrete Fourier transformation which can be used for trigonometric interpolation and also as a numerical approximation to the continuous Fourier integral. It can be realized efficiently by Goertzel's algorithm or the family of fast Fourier transformation methods. For real valued even functions the computationally simpler discrete cosine transformation can be applied. Several computer experiments demonstrate the principles of trigonometric interpolation and nonlinear filtering.
Nonequilibrium quantum thermodynamics in Coulomb crystals
NASA Astrophysics Data System (ADS)
Cosco, F.; Borrelli, M.; Silvi, P.; Maniscalco, S.; De Chiara, G.
2017-06-01
We present an in-depth study of the nonequilibrium statistics of the irreversible work produced during sudden quenches in proximity to the structural linear-zigzag transition of ion Coulomb crystals in 1+1 dimensions. By employing both an analytical approach based on a harmonic expansion and numerical simulations, we show the divergence of the average irreversible work in proximity to the transition. We show that the nonanalytic behavior of the work fluctuations can be characterized in terms of the critical exponents of the quantum Ising chain. Due to the technological advancements in trapped-ion experiments, our results can be readily verified.
The Coulomb Anomaly in Strongly Disordered Films
1992-01-01
r- AD-A271 0951 III [II[ I[Il ~ !!D T ! SC T 0 •9 3 The Coulomb Anomaly in Strongly Disordered FiiA 4 ’ Shih-Ying Hsu and J.M. Valles, Jr...strongly disordered quench condensed granular films are presented. The strength of this anomaly grows with increasing sheet resistance, RN, at low RN...Increases in the static disorder in metal The disordered films were deposited onto films degrades the screening capabilities of cooled substrates (-’ 8K
Bound eigenstates for two truncated Coulomb potentials
NASA Astrophysics Data System (ADS)
Singh, David; Varshni, Y. P.; Dutt, Ranabir
1985-07-01
The eigenvalue problem for two particles interacting through the attractive truncated Coulomb potential, V(r)=-Ze2/(rp+βp)1/p, for p=1 and 2 is solved numerically. Energy eigenvalues accurate to within eight to six significant figures for the states 1s to 4f are calculated as a function of the truncation parameter β. It is found that the level ordering satisfies Enl>Enl' for l
Action principle for Coulomb collisions in plasmas
NASA Astrophysics Data System (ADS)
Hirvijoki, Eero
2016-09-01
An action principle for Coulomb collisions in plasmas is proposed. Although no natural Lagrangian exists for the Landau-Fokker-Planck equation, an Eulerian variational formulation is found considering the system of partial differential equations that couple the distribution function and the Rosenbluth-MacDonald-Judd potentials. Conservation laws are derived after generalizing the energy-momentum stress tensor for second order Lagrangians and, in the case of a test-particle population in a given plasma background, the action principle is shown to correspond to the Langevin equation for individual particles.
Particle Diffusion Due to Coulomb Scattering
V. Lebedev and S. Nagaitsev
2002-06-03
Conventionally, the multiple and single particle scattering in a storage ring are considered to be independent. Such an approach is simple and often yields sufficiently accurate results. Nevertheless, there is a class of problems where such an approach is not adequate and the single and multiple scattering need to be considered together. This can be achieved by solving an integro-differential equation for the particle distribution function, which correctly treats particle Coulomb scattering in the presence of betatron motion. A derivation of the equation is presented in the article. A numerical solution for one practical case is also considered.
Nanoplasmonic renormalization and enhancement of Coulomb interactions
NASA Astrophysics Data System (ADS)
Durach, Maxim; Rusina, Anastasia; Klimov, Victor I.; Stockman, Mark I.
2008-08-01
In this paper we propose a general and powerful theory of the plasmonic enhancement of the many-body phenomena resulting in a closed expression for the surface plasmon-dressed Coulomb interaction. We illustrate this theory by computing dressed interaction explicitly for an important example of metal-dielectric nanoshells which exhibits a rich resonant behavior in magnitude and phase. This interaction is used to describe the nanoplasmonic-enhanced FÂ¨orster resonant energy transfer (FRET) between nanocrystal quantum dots near a nanoshell.
Nanoplasmonic renormalization and enhancement of Coulomb interactions
NASA Astrophysics Data System (ADS)
Durach, M.; Rusina, A.; Klimov, V. I.; Stockman, M. I.
2008-10-01
In this paper, we propose a general and powerful theory of the plasmonic enhancement of the many-body phenomena resulting in a closed expression for the surface plasmon-dressed Coulomb interaction. We illustrate this theory by computing the dressed interaction explicitly for an important example of metal-dielectric nanoshells which exhibits a rich resonant behavior in magnitude and phase. This interaction is used to describe the nanoplasmonic-enhanced Förster resonant energy transfer (FRET) between nanocrystal quantum dots near a nanoshell.
Coulombic dragging of molecular assemblies on nanotubes
NASA Astrophysics Data System (ADS)
Kral, Petr; Sint, Kyaw; Wang, Boyang
2009-03-01
We show by molecular dynamics simulations that polar molecules, ions and their assemblies could be Coulombically dragged on the surfaces of single-wall carbon and boron-nitride nanotubes by ionic solutions or individual ions moving inside the nanotubes [1,2]. We also briefly discuss highly selective ionic sieves based on graphene monolayers with nanopores [3]. These phenomena could be applied in molecular delivery, separation and desalination.[3pt] [1] Boyang Wang and Petr Kral, JACS 128, 15984 (2006). [0pt] [2] Boyang Wang and Petr Kral, Phys. Rev. Lett. 101, 046103 (2008). [0pt] [3] Kyaw Sint, Boyang Wang and Petr Kral, JACS, ASAP (2008).
Action principle for Coulomb collisions in plasmas
Hirvijoki, Eero
2016-09-14
In this study, an action principle for Coulomb collisions in plasmas is proposed. Although no natural Lagrangian exists for the Landau-Fokker-Planck equation, an Eulerian variational formulation is found considering the system of partial differential equations that couple the distribution function and the Rosenbluth-MacDonald-Judd potentials. Conservation laws are derived after generalizing the energy-momentum stress tensor for second order Lagrangians and, in the case of a test-particle population in a given plasma background, the action principle is shown to correspond to the Langevin equation for individual particles.
Action principle for Coulomb collisions in plasmas
Hirvijoki, Eero
2016-09-14
In this study, an action principle for Coulomb collisions in plasmas is proposed. Although no natural Lagrangian exists for the Landau-Fokker-Planck equation, an Eulerian variational formulation is found considering the system of partial differential equations that couple the distribution function and the Rosenbluth-MacDonald-Judd potentials. Conservation laws are derived after generalizing the energy-momentum stress tensor for second order Lagrangians and, in the case of a test-particle population in a given plasma background, the action principle is shown to correspond to the Langevin equation for individual particles.
NASA Astrophysics Data System (ADS)
Mathuna, Cian Ó.; Wang, Ningning; Kulkarni, Santosh; Roy, Saibal
2013-07-01
This paper introduces the concept of power supply on chip (PwrSoC) which will enable the development of next-generation, functionally integrated, power management platforms with applications in dc-dc conversion, gate drives, isolated power transmission and ultimately, high granularity, on-chip, power management for mixed-signal, SOC chips. PwrSoC will integrate power passives with the power management IC, in a 3D stacked or monolithic form factor, thereby delivering the performance of a highefficiency dc-dc converter within the footprint of a low-efficiency linear regulator. A central element of the PwrSoC concept is the fabrication of power micro-magnetics on silicon to deliver micro-inductors and micro-transformers. The paper details the magnetics on silicon process which combines thin film magnetic core technology with electroplated copper conductors. Measured data for micro-inductors show inductance operation up to 20 MHz, footprints down to 0.5 mm2, efficiencies up to 93% and dc current carrying capability up to 600 mA. Measurements on micro-transformers show voltage gain of approximately - 1 dB at between 10 MHz and 30 MHz. Contribution to the Topical Issue “International Semiconductor Conference Dresden-Grenoble - ISCDG 2012”, Edited by Gérard Ghibaudo, Francis Balestra and Simon Deleonibus.
Hendry, Anne; Taylor, Alison; Mercer, Stewart; Knight, Peter
2016-01-01
The Scottish Parliament recently passed legislation on integrating healthcare and social care to improve the quality and outcomes of care and support for people with multiple and complex needs across Scotland. This ambitious legislation provides a national framework to accelerate progress in person-centred and integrated care and support for the growing number of people who have multiple physical and mental health conditions and complex needs. Additional investment and improvement capacity is helping to commission support and services that are designed and delivered with people in local communities and in partnership with housing, community, voluntary and independent sectors.
Levin, Ira W; Bhargava, Rohit
2005-01-01
The recent development of Fourier transform infrared (FTIR) spectroscopic imaging has enhanced our capability to examine, on a microscopic scale, the spatial distribution of vibrational spectroscopic signatures of materials spanning the physical and biomedical disciplines. Recent activity in this emerging area has concentrated on instrumentation development, theoretical analyses to provide guidelines for imaging practice, novel data processing algorithms, and the introduction of the technique to new fields. To illustrate the impact and promise of this spectroscopic imaging methodology, we present fundamental principles of the technique in the context of FTIR spectroscopy and review new applications in various venues ranging from the physical chemistry of macromolecular systems to the detection of human disease.
Reconciling Coulomb breakup and neutron radiative capture
NASA Astrophysics Data System (ADS)
Capel, P.; Nollet, Y.
2017-07-01
The Coulomb-breakup method to extract the cross section for neutron radiative capture at astrophysical energies is analyzed in detail. In particular, its sensitivity to the description of the neutron-core continuum is ascertained. We consider the case of 14C(n ,γ )15C for which both the radiative capture at low energy and the Coulomb breakup of 15C into 14C+n on Pb at 68 MeV/nucleon have been measured with accuracy. We confirm the direct proportionality of the cross section for both reactions to the square of the asymptotic normalization constant of 15C observed by Summers and Nunes [Phys. Rev. C 78, 011601(R) (2008), 10.1103/PhysRevC.78.011601], but we also show that the 14C-n continuum plays a significant role in the calculations. Fortunately, the method proposed by Summers and Nunes can be improved to absorb that continuum dependence. We show that a more precise radiative-capture cross section can be extracted selecting the breakup data at forward angles and low 14C-n relative energies.
Improved Shell models for screened Coulomb balls
NASA Astrophysics Data System (ADS)
Bonitz, M.; Kaehlert, H.; Henning, C.; Baumgartner, H.; Filinov, A.
2006-10-01
Spherical Coulomb crystals in dusty plasmas [1] are well described by an isotropic Yukawa-type pair interaction and an external parabolic confinement as was shown by extensive molecular dynamics simulations [2]. A much simpler description is possible with analytical shell models which have been derived for Yukawas plasmas in [3,4]. Here we analyze improved Yukawa shell models which include correlations along the lines proposed for Coulomb crystals in [5]. The shell configurations are efficiently evaluated using a Monte Carlo procedure. [1] O. Arp, A. Piel and A. Melzer, Phys. Rev. Lett. 93, 165004 (2004). [2] M. Bonitz, D. Block, O. Arp, V. Golunychiy, H. Baumgartner, P. Ludwig, A. Piel and A. Filinov, Phys. Rev. Lett. 96, 075001 (2006). [3] H. Totsuji, C. Totsuji, T. Ogawa, and K. Tsuruta, Phys. Rev. E 71, 045401 (2005). [4] C. Henning, M. Bonitz, A. Piel, P. Ludwig, H. Baumgartner, V. Golubnichiy, and D. Block, submitted to Phys. Rev. E [5] W.D. Kraeft and M. Bonitz, J. Phys. Conf. Ser. 35, 94 (2006).
Thermodynamic properties of screened Coulomb balls
NASA Astrophysics Data System (ADS)
Bonitz, M.; Baumgartner, H.; Filinov, A.
2006-10-01
Complex plasmas in parabolic traps [1,2], especially Coulomb balls, can easily reach a strongly coupled state which is of great current interest in many fields, including trapped ions, ultracold plasmas and condensed matter. The advantage of the dust crystals is the direct experimental access to the individual particle positions, allowing for precision comparisons with theoretical models and numerical simulations. In this work the dependence of melting points of mesoscopic spherical crystals on the screening and particle number is analyzed. We present analytical results which are compared with simulation and experimental data [3,4,5]. It is shown that the influence of the screening on structural properties of these mesoscopic systems exhibts also a strong impact on the melting behavior. This analysis is based on Metropolis thermodynamic Monte Carlo simulations to obtain first principle thermodynamic properties of the strongly correlated Coulomb clusters. Finally, our results allow to propose a new non-invasive diagnostic to determine the dust temperature. [1] O. Arp, A. Piel and A. Melzer, Phys. Rev. Lett. 93, 165004 (2004).[2] P. Ludwig, S. Kosse and M. Bonitz, Phys. Rev. E 71, 046403 (2005).[3] M. Bonitz, D. Block, O. Arp, V. Golunychiy, H. Baumgartner, P. Ludwig, A. Piel and A. Filinov, Phys. Rev. Lett. 96, 075001 (2006). [4] O.S. Vaulina, S.A. Khrapak and G.E. Morfill, Phys. Rev. E 66, 016404 (2002). [5] J.P. Schiffer, Phys. Rev. Lett. 88, 205003 (2002)
Coulomb excitation of radioactive {sup 79}Pb
Lister, C.J.; Blumenthal, D.; Davids, C.N.
1995-08-01
The technical challenges expected in experiments with radioactive beams can already be explored by using ions produced in primary reactions. In addition, the re-excitation of these ions by Coulomb excitation allows a sensitive search for collective states that are well above the yrast line. We are building an experiment to study Coulomb excitation of radioactive ions which are separated from beam particles by the Fragment Mass Analyzer. An array of gamma detectors will be mounted at the focal plane to measure the gamma radiation following re-excitation. Five Compton-suppressed Ge detectors and five planar LEPS detectors will be used. The optimum experiment of this type appears to be the study of {sup 79}Rb following the {sup 24}Mg ({sup 58}Ni,3p) reaction. We calculate that about 5 x 10{sup 5} {sup 79}Rb nuclei/second will reach the excitation foil. This rubidium isotope was selected for study as it is strongly produced and is highly deformed, so easily re-excited. The use of a {sup 58}Ni re-excitation foil offers the best yields. After re-excitation the ions will be subsequently transported into a shielded beamdump to prevent the accumulation of activity.
Transforming Education into the 21st Century by Integrating 1:1 iPads
ERIC Educational Resources Information Center
Belcher, Kermit E.
2014-01-01
Teachers at Mason County High School are changing from predominantly teacher led instruction to increased student engagement by providing blended learning opportunities through technology integration. Every student and teacher at Mason County High School was provided an iPad as a resource to enhance instruction. The purpose of this case study is…
Capacity Building through Integration and Transformational Leadership--A Case Study
ERIC Educational Resources Information Center
Stöcklin, Sacha
2011-01-01
This article suggests that educational managers can have an influence through leadership by establishing certain moderators that integrate and shape the faculty into a solid team working towards a high performing organisation. The study looks at a case in China and draws suggestions that could be used in other similar settings. The conclusion is…
Revenue Forecasting to Integrate CCC Planning and Resource Allocation for Transformative Leadership
ERIC Educational Resources Information Center
Hovey, Ann
2012-01-01
In recent years the majority of California community colleges evaluated for re-accreditation received sanctions requiring documented improvement in the integration of college planning and budgeting processes. This study explores the challenges colleges face and the best practices utilized by successful colleges in implementing integrated…
Transforming Education into the 21st Century by Integrating 1:1 iPads
ERIC Educational Resources Information Center
Belcher, Kermit E.
2014-01-01
Teachers at Mason County High School are changing from predominantly teacher led instruction to increased student engagement by providing blended learning opportunities through technology integration. Every student and teacher at Mason County High School was provided an iPad as a resource to enhance instruction. The purpose of this case study is…
Schwarzhans, Jan-Philipp; Wibberg, Daniel; Winkler, Anika; Luttermann, Tobias; Kalinowski, Jörn; Friehs, Karl
2016-01-01
The non-conventional yeast Pichia pastoris is a popular host for recombinant protein production in scientific research and industry. Typically, the expression cassette is integrated into the genome via homologous recombination. Due to unknown integration events, a large clonal variability is often encountered consisting of clones with different productivities as well as aberrant morphological or growth characteristics. In this study, we analysed several clones with abnormal colony morphology and discovered unpredicted integration events via whole genome sequencing. These include (i) the relocation of the locus targeted for replacement to another chromosome (ii) co-integration of DNA from the E. coli plasmid host and (iii) the disruption of untargeted genes affecting colony morphology. Most of these events have not been reported so far in literature and present challenges for genetic engineering approaches in this yeast. Especially, the presence and independent activity of E. coli DNA elements in P. pastoris is of concern. In our study, we provide a deeper insight into these events and their potential origins. Steps preventing or reducing the risk for these phenomena are proposed and will help scientists working on genetic engineering of P. pastoris or similar non-conventional yeast to better understand and control clonal variability. PMID:27958335
Revenue Forecasting to Integrate CCC Planning and Resource Allocation for Transformative Leadership
ERIC Educational Resources Information Center
Hovey, Ann
2012-01-01
In recent years the majority of California community colleges evaluated for re-accreditation received sanctions requiring documented improvement in the integration of college planning and budgeting processes. This study explores the challenges colleges face and the best practices utilized by successful colleges in implementing integrated…
Effect of Coulomb interaction on multi-electronwave packet dynamics
Shiokawa, T.; Takada, Y.; Konabe, S.; Hatsugai, Y.; Muraguchi, M.; Endoh, T.; Shiraishi, K.
2013-12-04
We have investigated the effect of Coulomb interaction on electron transport in a one-dimensional nanoscale structure using a multi-electron wave packet approach. To study the time evolution, we numerically solve the time-dependent Hartree-Fock equation, finding that the electron wave packet dynamics strongly depends on the Coulomb interaction strength. When the Coulomb interaction is large, each electron wave packet moves separately in the presence of an electric field. With weak Coulomb interaction, however, the electron wave packets overlap, forming and moving as one collective wave packet.
Coulomb and spin-orbit interaction matrix elements in the ? configuration
NASA Astrophysics Data System (ADS)
Lo, Edwin
1998-11-01
The 0953-4075/31/21/006/img2 configuration is analysed in group-theoretical terms. Starting from the table given by Condon and Odabasi for the configuration 0953-4075/31/21/006/img2, we determine a set of convenient group-theoretical basis states, and rewrite the Coulomb matrix elements in terms of this new basis. Linear combinations from the different parts of the Coulomb operators are formed such that they have simple group transformation properties in our scheme. The sequence of groups that we use is 0953-4075/31/21/006/img4, where T denotes the isospin of Simonis et al, in which electrons with the same angular momentum l but different principal quantum numbers n are accommodated by introducing the eigenvalue 0953-4075/31/21/006/img5 of 0953-4075/31/21/006/img6. Using the Wigner-Eckart theorem and selection rules on the higher symmetry groups, the tables of the Coulomb and spin-orbit matrix elements for the reconstituted operators (with simple group transformation properties) are much simplified in terms of these basis states.
Phase-integral solution of the radial Dirac equation
Linnaeus, Staffan
2010-03-15
A phase-integral (WKB) solution of the radial Dirac equation is constructed, retaining perfect symmetry between the two components of the wave function and introducing no singularities except at the classical transition points. The potential is allowed to be the time component of a four-vector, a Lorentz scalar, a pseudoscalar, or any combination of these. The key point in the construction is the transformation from two coupled first-order equations constituting the radial Dirac equation to a single second-order Schroedinger-type equation. This transformation can be carried out in infinitely many ways, giving rise to different second-order equations but with the same spectrum. A unique transformation is found that produces a particularly simple second-order equation and correspondingly simple and well-behaved phase-integral solutions. The resulting phase-integral formulas are applied to unbound and bound states of the Coulomb potential. For bound states, the exact energy levels are reproduced.
Extract transformation loading from OLTP to OLAP data using pentaho data integration
NASA Astrophysics Data System (ADS)
Salaki, R. J.; Waworuntu, J.; Tangkawarow, I. R. H. T.
2016-04-01
The design of the data warehouse in this case is expected to solve the problem of evaluation of learning results as well as the relevance of the information received to support decision-making by the leader. Data warehouse design is very important, which is designed to utilize the existing resources of information. GPA (Grade Point Average) data warehouse can be used for the process of evaluation, decision making and even further planning of the study program of PTIK. The diversity of data sources in the course PTIK make decisionmaking and evaluation process becomes not easier. Pentaho Data Integration is used to integrate data in PTIK easy. CPI data warehouse design with multidimensional database modeling approach using the dimension tables and fact tables.
Path integral approach to the pricing of timer options with the Duru-Kleinert time transformation.
Liang, L Z J; Lemmens, D; Tempere, J
2011-05-01
In this paper, a time substitution as used by Duru and Kleinert in their treatment of the hydrogen atom with path integrals is performed to price timer options under stochastic volatility models. We present general pricing formulas for both the perpetual timer call options and the finite time-horizon timer call options. These general results allow us to find closed-form pricing formulas for both the perpetual and the finite time-horizon timer options under the 3/2 stochastic volatility model as well as under the Heston stochastic volatility model. For the treatment of timer options under the 3/2 model we will rely on the path integral for the Morse potential, with the Heston model we will rely on the Kratzer potential. © 2011 American Physical Society
Oscillator-Morse-Coulomb mappings and algebras for constant or position-dependent mass
Quesne, C.
2008-02-15
The bound-state solutions and the su(1,1) description of the d-dimensional radial harmonic oscillator, the Morse, and the D-dimensional radial Coulomb Schroedinger equations are reviewed in a unified way using the point canonical transformation method. It is established that the spectrum generating su(1,1) algebra for the first problem is converted into a potential algebra for the remaining two. This analysis is then extended to Schroedinger equations containing some position-dependent mass. The deformed su(1,1) construction recently achieved for a d-dimensional radial harmonic oscillator is easily extended to the Morse and Coulomb potentials. In the last two cases, the equivalence between the resulting deformed su(1,1) potential algebra approach and a previous deformed shape invariance one generalizes to a position-dependent mass background a well-known relationship in the context of constant mass.
NASA Astrophysics Data System (ADS)
Ngo, Nam Quoc; Song, Yufeng; Lin, Bo
2011-02-01
We present the design and analysis of a wideband and tunable optical Hilbert transformer (OHT) using a tunable waveguide-based finite-impulse response (FIR) filter structure by using the digital filter design method and the Remez algorithm. The tunable Nth-order waveguide-based FIR filter, which simply consists of N delay lines, N tunable couplers, N tunable phase shifters and a combiner, can be tuned, by thermally adjusting the tunable couplers and tunable phase shifters, to tune the bandwidth of an OHT using silica-based planar lightwave circuit (PLC) technology. To demonstrate the effectiveness of the method, the simulation results have an excellent agreement with the theoretical predictions. The tunable OHT can function as a wideband and tunable 90° phase shifter and thus has many potential applications. The two unique features of wideband characteristic (up to ~ 2 THz) and tunable bandwidth (THz tuning range) of the proposed OHT cannot be obtained from the existing OHTs.
A Fully Integrated Global Strategic Supply Network - A Critical Enabler of DoD Transformation
2004-01-01
3.1 Supply Chain Management Defined The Council of Logistics Management (CLM) defines Supply Chain Management ( SCM ) as “the process of planning...point of consumption for the purpose of conforming to customers requirements. “1 Effective SCM has become a core...leaders are expecting SCM to provide them improved methods of integrating their businesses with both suppliers and customers, while driving ever higher
Pattern Representation and Evaluation of Data through Integration Correlation, and Transformation
2014-02-01
iterative process to translate the CWA results into requirements for prototype visualizations. Mockup visualizations were developed for an integrated...stream (Milestone 2) as will be detailed later in this report. The results of the cognitive work analysis (reportable outcome 1) and prototype mockups ...reportable outcome 2) are detailed below. Each mockup underwent a series of design iterations to ensure that the visualizations made sense for the
NASA Astrophysics Data System (ADS)
Khan, Farrukh I.; Schinn, Dustin S.
2013-08-01
A new business plan that enables policy transformation and resource mobilization at the national and international level, while improving access to resources, will allow the Green Climate Fund to integrate development goals and action on climate change.
InTeGrate: Transforming the Teaching of Geoscience and Sustainability
NASA Astrophysics Data System (ADS)
Blockstein, D.; Manduca, C. A.; Bralower, T. J.; Castendyk, D.; Egger, A. E.; Gosselin, D. C.; Iverson, E. A.; Matson, P. A.; MacGregor, J.; Mcconnell, D. A.; Mogk, D. W.; Nevle, R. J.; Oches, E. A.; Steer, D. N.; Wiese, K.
2012-12-01
InTeGrate is an NSF-funded community project to improve geoscience literacy and build a workforce that can apply geoscience principles to address societal issues. Three workshops offered this year by InTeGrate and its partner, On the Cutting Edge, addressed strategies for bringing together geoscience and sustainability within geoscience courses and programs, in interdisciplinary courses and programs, and in courses and programs in other disciplines or schools including arts and humanities, health science, and business. Participants in all workshops described the power of teaching geoscience in the context of sustainability and the utility of this approach in engaging students with geoscience, including student populations not traditionally represented in the sciences. Faculty involved in both courses and programs seek to teach important skills including the ability to think about systems and to make connections between local observations and challenges and global phenomena and issues. Better articulation of these skills, including learning outcomes and assessments, as well as documenting the relationship between these skills and employment opportunities were identified as important areas for further work. To support widespread integration of geoscience and sustainability concepts, these workshops initiated collections describing current teaching activities, courses, and programs. InTeGrate will continue to build these collections in collaboration with On the Cutting Edge and Building Strong Geoscience Departments, and through open contributions by individual faculty and programs. In addition, InTeGrate began developing new teaching modules and courses. Materials for use in introductory geoscience and environmental science/studies courses, distance learning courses, and courses for education majors are being developed and tested by teams of faculty drawn from at least three institutions, including several members from two-year colleges. An assessment team is
Scalar vertex operator for bound-state QED in the Coulomb gauge
Holmberg, Johan
2011-12-15
Adkins's result [Phys. Rev. D 34, 2489 (1986)] for the time component of the renormalized vertex operator in Coulomb-gauge QED is separated according to its tensor structure and some of the Feynman parameter integrals are carried out analytically, yielding a form suited for numerical bound-state QED calculations. This modified form is applied to the evaluation of the self-energy shift to the binding energy in hydrogenic ions of high nuclear charge.
Coulomb crystallization in classical and quantum systems
NASA Astrophysics Data System (ADS)
Bonitz, Michael
2007-11-01
Coulomb crystallization occurs in one-component plasmas when the average interaction energy exceeds the kinetic energy by about two orders of magnitude. A simple road to reach such strong coupling consists in using external confinement potentials the strength of which controls the density. This has been succsessfully realized with ions in traps and storage rings and also in dusty plasma. Recently a three-dimensional spherical confinement could be created [1] which allows to produce spherical dust crystals containing concentric shells. I will give an overview on our recent results for these ``Yukawa balls'' and compare them to experiments. The shell structure of these systems can be very well explained by using an isotropic statically screened pair interaction. Further, the thermodynamic properties of these systems, such as the radial density distribution are discussed based on an analytical theory [3]. I then will discuss Coulomb crystallization in trapped quantum systems, such as mesoscopic electron and electron hole plasmas in coupled layers [4,5]. These systems show a very rich correlation behavior, including liquid and solid like states and bound states (excitons, biexcitons) and their crystals. On the other hand, also collective quantum and spin effects are observed, including Bose-Einstein condensation and superfluidity of bound electron-hole pairs [4]. Finally, I consider Coulomb crystallization in two-component neutral plasmas in three dimensions. I discuss the necessary conditions for crystals of heavy charges to exist in the presence of a light component which typically is in the Fermi gas or liquid state. It can be shown that their exists a critical ratio of the masses of the species of the order of 80 [5] which is confirmed by Quantum Monte Carlo simulations [6]. Familiar examples are crystals of nuclei in the core of White dwarf stars, but the results also suggest the existence of other crystals, including proton or α-particle crystals in dense matter
Relativistic Coulomb excitation of 88Kr
NASA Astrophysics Data System (ADS)
Moschner, K.; Blazhev, A.; Jolie, J.; Warr, N.; Boutachkov, P.; Bednarczyk, P.; Sieja, K.; Algora, A.; Ameil, F.; Bentley, M. A.; Brambilla, S.; Braun, N.; Camera, F.; Cederkäll, J.; Corsi, A.; Danchev, M.; DiJulio, D.; Fahlander, C.; Gerl, J.; Giaz, A.; Golubev, P.; Górska, M.; Grebosz, J.; Habermann, T.; Hackstein, M.; Hoischen, R.; Kojouharov, I.; Kurz, N.; Mǎrginean, N.; Merchán, E.; Möller, T.; Naqvi, F.; Nara Singh, B. S.; Nociforo, C.; Pietralla, N.; Pietri, S.; Podolyák, Zs.; Prochazka, A.; Reese, M.; Reiter, P.; Rudigier, M.; Rudolph, D.; Sava, T.; Schaffner, H.; Scruton, L.; Taprogge, J.; Thomas, T.; Weick, H.; Wendt, A.; Wieland, O.; Wollersheim, H.-J.
2016-11-01
To investigate the systematics of mixed-symmetry states in N =52 isotones, a relativistic Coulomb excitation experiment was performed during the PreSPEC campaign at the GSI Helmholtzzentrum für Schwerionenforschung to determine E 2 transition strengths to 2+ states of the radioactive nucleus 88Kr. Absolute transition rates could be measured towards the first and third 2+ states. For the latter a mixed-symmetry character is suggested on the basis of the indication for a strong M 1 transition to the fully symmetric 21+ state, extending the knowledge of the N =52 isotones below Z =40 . A comparison with the proton-neutron interacting boson model and shell-model predictions is made and supports the assignment.
Powerful Coulomb-drag thermoelectric engine
NASA Astrophysics Data System (ADS)
Daré, A.-M.; Lombardo, P.
2017-09-01
We investigate a thermoelectric nanoengine whose properties are steered by Coulomb interaction. The device whose design decouples charge and energy currents is made up of two interacting quantum dots connected to three different reservoirs. We show that, by tailoring the tunnel couplings, this setup can be made very attractive for energy-harvesting prospects, due to a delivered power that can be of the order of the quantum bound [R. S. Whitney, Phys. Rev. Lett. 112, 130601 (2014), 10.1103/PhysRevLett.112.130601; Entropy 18, 208 (2016), 10.3390/e18060208], with a concomitant fair efficiency. To unveil its properties beyond the sequential quantum master equation, we apply a nonequilibrium noncrossing approximation in the Keldysh Green's function formalism, and a quantum master equation that includes cotunneling processes. Both approaches are rather qualitatively similar in a large operating regime where sequential tunneling alone fails.
Cluster Dynamics: Fast Reactions and Coulomb Explosion
NASA Astrophysics Data System (ADS)
Poth, Lutz; Wisniewski, Eric S.; Welford Castleman, A., Jr.
2002-07-01
One of the enduring mysteries of chemistry is exactly what happens during the few femtoseconds it takes for a chemical reaction to transpire. We see what goes in and what comes out, but the in between happens so fast it has proved devilishly hard to study. One promising area of investigation involves the use of clusters—tiny atomic or molecular assemblages with weak bonding. Clusters can be rapidly ionized using laser pulses of very short duration, producing like charges of sufficient intensity and closeness to cause explosive repulsion, called Coulomb explosion. By carefully adjusting the delivery interval between femtosecond-duration laser pulses to clusters, the authors have begun to reveal the secrets of reaction dynamics.
A coulombic hypothesis of mitochondrial oxidative phosphorylation.
Malpress, F H
1984-08-21
A coulombic hypothesis of mitochondrial oxidative phosphorylation is presented, founded upon the evidence for negative fixed charge formation during electron transport chain activity. The intermediary force is electrostatic (psi H) and not electrochemical (delta mu H). The electrochemical potential of the chemiosmotic hypothesis is identified as a "phantom" parameter which owes its delusive existence to the procedures by which it is measured. The connection between psi H and the conditional delta mu H values is examined; it entails the use of a variable conversion factor, f, where delta mu H (mV) = f psi H, and the concept of the "protonic status" of the diffuse double layer. A number of problems which beset the chemiosmotic view are reappraised in the light of the new interpretation, and find authentic solutions.
The ghost propagator in Coulomb gauge
Watson, P.; Reinhardt, H.
2011-05-23
We present results for a numerical study of the ghost propagator in Coulomb gauge whereby lattice results for the spatial gluon propagator are used as input to solving the ghost Dyson-Schwinger equation. We show that in order to solve completely, the ghost equation must be supplemented by a boundary condition (the value of the inverse ghost propagator dressing function at zero momentum) which determines if the solution is critical (zero value for the boundary condition) or subcritical (finite value). The various solutions exhibit a characteristic behavior where all curves follow the same (critical) solution when going from high to low momenta until 'forced' to freeze out in the infrared to the value of the boundary condition. The boundary condition can be interpreted in terms of the Gribov gauge-fixing ambiguity; we also demonstrate that this is not connected to the renormalization. Further, the connection to the temporal gluon propagator and the infrared slavery picture of confinement is discussed.
Experimental realization of a Coulomb blockade refrigerator
NASA Astrophysics Data System (ADS)
Feshchenko, A. V.; Koski, J. V.; Pekola, J. P.
2014-11-01
We present an experimental realization of a Coulomb blockade refrigerator (CBR) based on a single-electron transistor (SET). In the present structure, the SET island is interrupted by a superconducting inclusion to permit charge transport while preventing heat flow. At certain values of the bias and gate voltages, the current through the SET cools one of the junctions. The measurements follow the theoretical model down to ˜80 mK, which was the base temperature of the current measurements. The observed cooling increases rapidly with decreasing temperature, in agreement with the theory, reaching about a 15 mK drop at the base temperature. The CBR appears as a promising electronic cooler at temperatures well below 100 mK.
Ion Coulomb Crystals and Their Applications
NASA Astrophysics Data System (ADS)
Drewsen, Michael
The following text will give a brief introduction to the physics of the spatially ordered structures, so-called Coulomb crystals, that appear when confined ions are cooled to sufficiently low temperatures. It will as well briefly comment on the very diverse scientific applications of such crystals, which have emerged in the past two decades. While this document lacks figures and many specific references, it is the hope, not the text will stimulate the reader to dig deeper into one or more of the discussed subjects, and inspire her/him to think about new potential applications. A fully referenced journal article of essentially the same text can be found in Physica B 460, 105 (2015) [1].
Coulomb energy differences in isobaric multiplets
Lenzi, S. M.; Farnea, E.; Bazzacco, D.; Brandolini, F.; Lunardi, S.; Mason, P.; Menegazzo, R.; Nespolo, M.; Ur, C. A.; Della Vedova, F.; Marginean, N.; Napoli, D. R.; De Angelis, G.; Axiotis, M.; Gadea, A.; Ionescu-Bujor, M.; Bucurescu, D.; Iordachescu, A.; Bizzeti-Sona, A. M.; Bizzeti, P. G.
2007-02-12
By comparing the excitation energies of analogue states in isobaric multiplets, several nuclear structure properties can be studied as a function of the angular momentum up to high spin states. In particular, the mirror nuclei 35Ar and 35Cl show large differences between the excitation energies of analogue negative-parity states at high spin, confirming the important contribution of the relativistic electromagnetic spin-orbit interaction to the Coulomb energy. The single-particle character of the configuration of these states is reproduced with very good accuracy by shell model calculations in the sd and pf shells valence space. In addition, evidence of isospin mixing is deduced from the El transitions linking positive and negative parity states.
Simulating Coulomb collisions in a magnetized plasma
Hinton, Fred L.
2008-04-15
The problem of simulating ion-ion Coulomb collisions in a plasma in a strong magnetic field is considered. No assumption is made about the ion distribution function except that it is independent of the gyrophase angle, consistent with the assumption that the ion gyrofrequency is much larger than the ion-ion collision frequency. A Langevin method is presented which time-advances the components of a particle's velocity parallel and perpendicular to the magnetic field, without following the rapidly changing gyrophase. Although the standard Monte Carlo procedure, which uses random sampling, can be used, it is also possible to use a deterministic sampling procedure, where the samples are determined by the points which would be used in a numerical quadrature formula for moments of the Fokker-Planck Green's function. This should reduce the sampling noise compared with the Monte Carlo collision method.
Tabletop nucleosynthesis driven by cluster Coulomb explosion.
Last, Isidore; Jortner, Joshua
2006-10-27
Coulomb explosion of completely ionized (CH4)n, (NH3)n, and (H2O)n clusters will drive tabletop nuclear reactions of protons with 12C6+, 14N7+, and 16O8+ nuclei, extending the realm of nuclear reactions driven by ultraintense laser-heterocluster interaction. The realization for nucleosynthesis in exploding cluster beams requires complete electron stripping from the clusters (at laser intensities I(M) > or = 10(19) W cm(-2)), the utilization of nanodroplets of radius 300-700 A for vertical ionization, and the attainment of the highest energies for the nuclei (i.e., approximately 30 MeV for heavy nuclei and approximately 3 MeV for protons).
The ghost propagator in Coulomb gauge
NASA Astrophysics Data System (ADS)
Watson, P.; Reinhardt, H.
2011-05-01
We present results for a numerical study of the ghost propagator in Coulomb gauge whereby lattice results for the spatial gluon propagator are used as input to solving the ghost Dyson-Schwinger equation. We show that in order to solve completely, the ghost equation must be supplemented by a boundary condition (the value of the inverse ghost propagator dressing function at zero momentum) which determines if the solution is critical (zero value for the boundary condition) or subcritical (finite value). The various solutions exhibit a characteristic behavior where all curves follow the same (critical) solution when going from high to low momenta until `forced' to freeze out in the infrared to the value of the boundary condition. The boundary condition can be interpreted in terms of the Gribov gauge-fixing ambiguity; we also demonstrate that this is not connected to the renormalization. Further, the connection to the temporal gluon propagator and the infrared slavery picture of confinement is discussed.
Coulomb explosion sputtering of selectively oxidized Si
NASA Astrophysics Data System (ADS)
Karmakar, P.; Bhattacharjee, S.; Naik, V.; Sinha, A. K.; Chakrabarti, A.
2010-05-01
We have studied the sputtering of a unique system comprising of coexisting silicon and silicon oxide surfaces due to the impact of multiply charged Arq + ions. Such surfaces are produced by oblique angle oxygen ion bombardment on Si(100), which results in one side oxidized ripple formation due to preferential oxygen implantation. It is observed by atomic force microscopy and conducting atomic force microscopy studies that the higher the potential energy of the Arq + ion, the higher the sputtering yield of the nonconducting (oxide) side of the ripple as compared to the semiconducting side while ensuring an identical irradiation and measurement condition. It also shows experimentally the potential of highly charged ions in the gentle cleaning or tailoring of nanostructures. The results are explained in terms of the Coulomb explosion model, where potential sputtering depends on the conductivity of the ion impact sites.
Zhou, Chengfeng; Jiang, Wei; Cheng, Qingzheng; Via, Brian K.
2015-01-01
This research addressed a rapid method to monitor hardwood chemical composition by applying Fourier transform infrared (FT-IR) spectroscopy, with particular interest in model performance for interpretation and prediction. Partial least squares (PLS) and principal components regression (PCR) were chosen as the primary models for comparison. Standard laboratory chemistry methods were employed on a mixed genus/species hardwood sample set to collect the original data. PLS was found to provide better predictive capability while PCR exhibited a more precise estimate of loading peaks and suggests that PCR is better for model interpretation of key underlying functional groups. Specifically, when PCR was utilized, an error in peak loading of ±15 cm−1 from the true mean was quantified. Application of the first derivative appeared to assist in improving both PCR and PLS loading precision. Research results identified the wavenumbers important in the prediction of extractives, lignin, cellulose, and hemicellulose and further demonstrated the utility in FT-IR for rapid monitoring of wood chemistry. PMID:26576321
NASA Astrophysics Data System (ADS)
Cox, J. Neal; Sedayao, J.; Shergill, Gurmeet S.; Villasol, R.; Haaland, David M.
1991-03-01
Fourier transform infrared spectrophotometry (FTIR) is a valuable technique for monitoring thin films used in semiconductor device manufacture. Determinations of the constituent contents in borophosphosilicate (BPSG) phosphosilicate (PSG) silicon oxynitride (SiON:H and spin-on-glass (SOG) thin films are a few applications. Due to the nature of the technique FTIR instrumentation is one of the most extensively computer-dependent pieces of equipment that is likely to be found in a microelectronics plant. In the role of fab monitor or reactor characterization tool FTIR instruments can rapidly generate large amounts of data. Also the drive for greater accuracy and tighter precision is leading to the development of increasingly sophisticated data processing software that tax the computing abilities of most instrument local data stations. By linking a local FTIR data station to a remote minicomputer its capabilities are greatly improved. We discuss three classes of enhancement. First the FTIR in the fab area communicates and interacts in real time with the minicomputer: transferring data segments to it instructing it to perform sophisticated processing and returning the results to the operator in the fab. Characterizations of PSG thin films by this approach are discussed. Second the spectra of large numbers of samples are processed locally. The large database is then transmitted to the minicomputer for study by statistical/graphics software. Results of CVD-reactor spatial profiling experiments for plasma SiON are presented. Third processing of calibration spectra is performed
Littlewood, Roland; Leavey, Gerard
2013-01-01
The psychological consequences of sexual abuse are generally serious and enduring, particularly when the perpetrator is known and trusted by the survivor. This paper explores the experiences of five contemplative nuns who were sexually abused by priests and the spiritual journeys that followed. In the context of an ethnographic study of contemplative practice, participant observation and in-depth interviews were used to examine the ways that the nuns sought to make sense of their experiences through a long process of solitary introspection. The pursuit of meaning was shaped by religious beliefs relating to forgiveness, sacrifice, and salvation. Thus, trauma was transformed into a symbolic religious narrative that shaped their sense of identity. They were able to restructure core beliefs and to manage their current relationships with priests more securely. They described regaining their spiritual well-being in ways that suggest a form of posttraumatic spiritual growth. We conclude by discussing the findings in the light of the existing literature on the interaction of trauma and spirituality. PMID:23296289
Watson, Jean; Foster, Roxie
2003-05-01
This paper presents a proposed model: The Attending Nursing Caring Model (ANCM) as an exemplar for advancing and transforming nursing practice within a reflective, theoretical and evidence-based context. Watson's theory of human caring is used as a guide for integrating theory, evidence and advanced therapeutics in the area of children's pain. The ANCM is offered as a programme for renewing the profession and its professional practices of caring-healing arts and science, during an era of decline, shortages, and crises in care, safety, and hospital and health reform. The ANCM elevates contemporary nursing's caring values, relationships, therapeutics and responsibilities to a higher/deeper order of caring science and professionalism, intersecting with other professions, while sustaining the finest of its heritage and traditions of healing.
Heddle, William; Roberton, Gayle; Mahoney, Sarah; Walters, Lucie; Strasser, Sarah; Worley, Paul
2014-01-01
Longitudinal integrated clerkships (LIC) in the first major clinical year in medical student training have been demonstrated to be at least equivalent to and in some areas superior to the "traditional block rotation" (TBR). Flinders University School of Medicine is starting a pilot changing the traditional teaching at the major Academic Medical Centre from TBR to LIC (50% of students in other locations in the medical school already have a partial or full LIC programme). This paper summarises the expected challenges presented at the "Rendez-Vous" Conference in October 2012: (a) creating urgency, (b) training to be a clinician rather than imparting knowledge, (c) resistance to change. We discuss the unexpected challenges that have evolved since then: (a) difficulty finalising the precise schedule, (b) underestimating time requirements, (c) managing the change process inclusively. Transformation of a "block rotation" to "LIC" medical student education in a tertiary academic teaching hospital has many challenges, many of which can be anticipated, but some are unexpected.
Benigni, Romualdo; Bossa, Cecilia; Tcheremenskaia, Olga; Battistelli, Chiara Laura; Giuliani, Alessandro
2015-02-01
The long-term carcinogenesis bioassays have played a central role in protecting human health, but for ethical and practical reasons their use is dramatically diminishing and the genotoxicity short-term tests have taken the pivotal role in the pre-screening of chemical carcinogenicity. However, this strategy cannot detect nongenotoxic carcinogens. Since up to 25% of IARC human carcinogens are recognized to have nongenotoxic mechanisms of action, the risk they pose to human health cannot be disregarded, and it is urgent to fill the gap in the tools for alternative testing. In this paper, we analyze from different perspectives the ability of Cell Transformation Assays to identify nongenotoxic carcinogens, and we conclude that the Syrian hamster embryo cells test is able to identify nongenotoxic carcinogens with 80-90% efficiency, and thus, can play an important role in integrated, alternative testing strategies. Copyright © 2015 Elsevier B.V. All rights reserved.
Known-to-Unknown Approach to Teach about Coulomb's Law
ERIC Educational Resources Information Center
Thamburaj, P. K.
2007-01-01
Analogies from life experiences help students understand various relationships presented in an introductory chemistry course. Coulomb's law is a complex relationship encountered in introductory general chemistry. A proper understanding of the relationships between the quantities involved in Coulomb's law is necessary in order for students to…
Known-to-Unknown Approach to Teach about Coulomb's Law
ERIC Educational Resources Information Center
Thamburaj, P. K.
2007-01-01
Analogies from life experiences help students understand various relationships presented in an introductory chemistry course. Coulomb's law is a complex relationship encountered in introductory general chemistry. A proper understanding of the relationships between the quantities involved in Coulomb's law is necessary in order for students to…
Dynamical effects in the Coulomb expansion following nuclear fragmentation
Chung, K.C.; Donangelo, R.; Schechter, H.
1987-09-01
The effects of the Coulomb expansion on the fragment kinetic energy spectrum for a fragmentating hot nuclear system is investigated. In particular, /sup 12/C-fragment spectra are calculated and compared with those predicted by the uniform expansion approximation. The results indicate that the energy spectra of fragments are quite sensitive to the details of the Coulomb expansion treatment.
a Field-Theoretical Investigation of 2-D Coulomb Systems with Short-Range Yukawa Repulsion.
NASA Astrophysics Data System (ADS)
Jargocki, Krzysztof Piotr
The two-dimensional Coulomb gas, consisting of positive and negative charges, is an important system which, on one hand, is equivalent to the vortex sector of the planar X-Y model, and, on the other, to the sine-Gordon field theory. In most treatments the charged particles are assumed to have a repulsive hard core which prevents arbitrarily close approaches. In the present work a new regularization scheme based on a soft short-range Yukawa repulsion between the Coulomb gas particles is presented. This formulation is transcribed into a local sine-Gordon-like field theory involving two Bose fields, one the original massless sine -Gordon field corresponding to the long-range Coulomb interaction and an auxiliary massive field corresponding to the short -range Yukawa repulsion. The resulting Lagrangian is not Hermitian. Using the techniques of functional integration, an effective field theory involving the Coulomb field alone is obtained by integrating out the massive field. The resulting Lagrangian is now Hermitian. Then a generalization of Peierls' inequality is used to make a variational calculation of the ground state energy of the Coulomb system. Unlike in the pure sine-Gordon case the theory has a well-defined ground state energy for (beta)q('2) > 2 (or (beta)c('2) > 8(pi)). A new method is used to derive the Kosterlitz -Thouless renormalization group equations, starting with the original sine-Gordon-like theory. The equations are identical to those found previously by other authors. A wave function renormalization is found to be necessary in addition to the normal ordering discussed by Coleman. A fermionized version of the theory is obtained, using the dictionary provided by Kogut and Susskind, which involves two Fermi fields and an electromagnetic potential. Position -space correlation functions are calculated at the critical point. The effective potential is computed in the one -loop approximation. A nonlinear field theory with derivative couplings is found to
On the decoupling between classical Coulomb matter and radiation
NASA Astrophysics Data System (ADS)
Alastuey, Angel; Appel, Walter
2000-02-01
We consider a model of matter coupled to radiation at equilibrium. Matter is described by a one-component plasma of classical point charges with Coulomb interactions, while radiation is represented by the classical transverse potential vector in Coulomb gauge. Using a straightforward generalization of the Bohr-van Leeuwen theorem, we show that the equilibrium properties of classical Coulomb matter remain unaffected by the presence of the classical radiation. As far as the real world is concerned, this decoupling does survive at large distances where both matter and radiation can be treated classically. This invalidates all the large-distances predictions, for the charge correlations, of the so-called Darwin models which incorporate retarded electromagnetic interactions beyond the instantaneous Coulomb potential. A second related important consequence is that the first relativistic corrections to the Coulomb thermodynamical quantities must be evaluated within the theory of quantum electrodynamics at finite temperature, even in a weakly relativistic and almost classical regime for matter.
NASA Astrophysics Data System (ADS)
Sandner, Thilo; Grasshoff, Thomas; Schenk, Harald; Kenda, Andreas
2012-03-01
A translatory MOEMS actuator with extraordinary large stroke - especially developed for fast optical path length modulation in miniaturized FTIR-spectrometers (FTS) - is presented. A precise translational out-of-plane oscillation at 500 Hz with large stroke of up to 1.2 mm is realized by means of an optimized MEMS design using four pantograph suspensions of the comparative large mirror plate with 5mm diameter. The MOEMS device is driven electro - statically resonant and is manufactured in a CMOS compatible SOI process. Up to +/- 600 μm amplitude (typically 1mm stroke) has been measured in vacuum of 30 Pa and 50 V driving voltage for an optimized pantograph design enabling reduced gas damping and higher driving efficiency. For FTS system integration the MOEMS actuator has been encapsulated in a hybrid optical vacuum package. In this paper we discuss the thermal influences of packaging technology on MOEMS behaviors more detail.
Resonant Auger decay driving intermolecular Coulombic decay in molecular dimers.
Trinter, F; Schöffler, M S; Kim, H-K; Sturm, F P; Cole, K; Neumann, N; Vredenborg, A; Williams, J; Bocharova, I; Guillemin, R; Simon, M; Belkacem, A; Landers, A L; Weber, Th; Schmidt-Böcking, H; Dörner, R; Jahnke, T
2014-01-30
In 1997, it was predicted that an electronically excited atom or molecule placed in a loosely bound chemical system (such as a hydrogen-bonded or van-der-Waals-bonded cluster) could efficiently decay by transferring its excess energy to a neighbouring species that would then emit a low-energy electron. This intermolecular Coulombic decay (ICD) process has since been shown to be a common phenomenon, raising questions about its role in DNA damage induced by ionizing radiation, in which low-energy electrons are known to play an important part. It was recently suggested that ICD can be triggered efficiently and site-selectively by resonantly core-exciting a target atom, which then transforms through Auger decay into an ionic species with sufficiently high excitation energy to permit ICD to occur. Here we show experimentally that resonant Auger decay can indeed trigger ICD in dimers of both molecular nitrogen and carbon monoxide. By using ion and electron momentum spectroscopy to measure simultaneously the charged species created in the resonant-Auger-driven ICD cascade, we find that ICD occurs in less time than the 20 femtoseconds it would take for individual molecules to undergo dissociation. Our experimental confirmation of this process and its efficiency may trigger renewed efforts to develop resonant X-ray excitation schemes for more localized and targeted cancer radiation therapy.
NASA Astrophysics Data System (ADS)
Cox, J. N.; Sedayao, J.; Shergill, G.; Villasol, R.; Haaland, D. M.
Fourier transform infrared spectrophotometry (FTIR) is a valuable technique for monitoring thin films used in semiconductor device manufacture. Determinations of the constituent contents in borophosphosilicate (BPSG), phosphosilicate (PSG), silicon oxynitride (SiON:H,OH), and spin-on-glass (SOG) thin films are a few applications. Due to the nature of the technique, FTIR instrumentation is one of the most extensively computer-dependent pieces of equipment that is likely to be found in a microelectronics plant. In the role of fab monitor or reactor characterization tool, FTIR instruments can rapidly generate large amounts of data. By linking a local FTIR data station to a remote minicomputer its capabilities are greatly improved. We discuss three caused of enhancement. First, the FTIR in the fab area communicates and interacts in real time with the minicomputer: transferring data segments to it, instructing it to perform sophisticated processing, and returning the result to the operator in the fab. Characterizations of PSG thin films by this approach are discussed. Second, the spectra of large numbers of samples are processed locally. The large database is then transmitted to the minicomputer for study by statistical/graphics software. Results of CVD-reactor spatial profiling experiments for plasma SiON are presented. Third, processing of calibration spectra is performed on the minicomputer to optimize the accuracy and precision of a Partial Least Squares analysis mode. This model is then transferred to the data station in the fab. The analysis of BPSG thin films is discussed in this regard. The prospects for fully automated at-line monitoring and for real-time, in-situ monitoring will be discussed.
Cox, J.N.; Sedayao, J.; Shergill, G.; Villasol, R. ); Haaland, D.M. )
1990-01-01
Fourier transform infrared spectrophotometry (FTIR) is a valuable technique for monitoring thin films used in semiconductor device manufacture. Determinations of the constituent contents in borophosphosilicate (BPSG), phosphosilicate (PSG), silicon oxynitride (SiON:H,OH), and spin-on-glass (SOG) thin films are a few applications. Due to the nature of the technique, FTIR instrumentation is one of the most extensively computer-dependent pieces of equipment that is likely to be found in a microelectronics plant. In the role of fab monitor or reactor characterization tool, FTIR instruments can rapidly generate large amounts of data. By linking a local FTIR data station to a remote minicomputer its capabilities are greatly improved. We discuss three caused of enhancement. First, the FTIR in the fab area communicates and interacts in real time with the minicomputer: transferring data segments to it, instructing it to perform sophisticated processing, and returning the result to the operator in the fab. Characterizations of PSG thin films by this approach are discussed. Second, the spectra of large numbers of samples are processed locally. The large database is then transmitted to the minicomputer for study by statistical/graphics software. Results of CVD-reactor spatial profiling experiments for plasma SiON are presented. Third, processing of calibration spectra is performed on the minicomputer to optimize the accuracy and precision of a Partial Least Squares'' analysis mode. This model is then transferred to the data station in the fab. The analysis of BPSG thin films is discussed in this regard. The prospects for fully automated at-line monitoring and for real-time, in-situ monitoring will be discussed. 10 refs., 4 figs.
NASA Astrophysics Data System (ADS)
Levin, S. B.; Yakovlev, S. L.; Elander, N.
2001-12-01
The three-body Coulomb Green's function asymptotic structure is studied by the stationary phase method for the convolution integral for the case of two charged particles. The stationary phase points are roots of the third degree polinomial with the coefficients depending on the position in configuration space.
Foss Durant, Anne; McDermott, Shawna; Kinney, Gwendolyn; Triner, Trudy
2015-01-01
In early 2010, leaders within Kaiser Permanente (KP) Northern California's Patient Care Services division embarked on a journey to embrace and embed core tenets of Caring Science into the practice, environment, and culture of the organization. Caring Science is based on the philosophy of Human Caring, a theory articulated by Jean Watson, PhD, RN, AHN-BC, FAAN, as a foundational covenant to guide nursing as a discipline and a profession. Since 2010, Caring Science has enabled KP Northern California to demonstrate its commitment to being an authentic person- and family-centric organization that promotes and advocates for total health. This commitment empowers KP caregivers to balance the art and science of clinical judgment by considering the needs of the whole person, honoring the unique perception of health and healing that each member or patient holds, and engaging with them to make decisions that nurture their well-being. The intent of this article is two-fold: 1) to provide context and background on how a professional practice framework was used to transform the ethic of caring-healing practice, environment, and culture across multiple hospitals within an integrated delivery system; and 2) to provide evidence on how integration of Caring Science across administrative, operational, and clinical areas appears to contribute to meaningful patient quality and health outcomes.
Durant, Anne Foss; McDermott, Shawna; Kinney, Gwendolyn; Triner, Trudy
2015-01-01
In early 2010, leaders within Kaiser Permanente (KP) Northern California’s Patient Care Services division embarked on a journey to embrace and embed core tenets of Caring Science into the practice, environment, and culture of the organization. Caring Science is based on the philosophy of Human Caring, a theory articulated by Jean Watson, PhD, RN, AHN-BC, FAAN, as a foundational covenant to guide nursing as a discipline and a profession. Since 2010, Caring Science has enabled KP Northern California to demonstrate its commitment to being an authentic person- and family-centric organization that promotes and advocates for total health. This commitment empowers KP caregivers to balance the art and science of clinical judgment by considering the needs of the whole person, honoring the unique perception of health and healing that each member or patient holds, and engaging with them to make decisions that nurture their well-being. The intent of this article is two-fold: 1) to provide context and background on how a professional practice framework was used to transform the ethic of caring-healing practice, environment, and culture across multiple hospitals within an integrated delivery system; and 2) to provide evidence on how integration of Caring Science across administrative, operational, and clinical areas appears to contribute to meaningful patient quality and health outcomes. PMID:26828076
Coupling constant metamorphosis, the Staeckel transform and superintegrability
Post, Sarah
2010-12-23
This paper is dedicated to the memory of Marcos Moshinsky. In this paper, we discuss the important role that coupling constant metamorphosis (CCM) and the Staeckel transform have played in the analysis of superintegrable systems. We explain the relation between the two and in particular show that they coincide when transforming between second-order superintegrable systems. Unlike in the case of second-order superintegrability, the quantum analog of CCM has only been proven for a subclass of systems with integrals of a specific form. We give the proof and as an application show the mapping of a family of superintegrable deformations of the simple harmonic oscillator to an associated family of superintegrable deformations of the Kepler-Coulomb potential.
Ultrafast Dynamics of Coulomb Correlated Excitons in Gallium Arsenide Quantum Wells
NASA Astrophysics Data System (ADS)
Mycek, Mary-Ann
We measure the transient nonlinear optical response of room temperature excitons in gallium arsenide quantum wells via multi-wave mixing experiments. The dynamics of the resonantly excited excitons is directly reflected by the ultrafast decay of the induced nonlinear polarization, which radiates the detected multi-wave mixing signal. We characterize this ultrafast coherent emission in both amplitude and phase, using time and frequency-domain measurement techniques, to better understand the role of Coulomb correlation in these systems. To interpret the experimental results, the nonlinear optical response of a dense medium is calculated using a model including Coulomb interaction. We contribute three new elements to previous theoretical and experimental studies of these systems. First, surpassing traditional time-integrated measurements, we temporally resolve the amplitude of the ultrafast coherent emission. Second, in addition to measuring the third-order four-wave mixing signal, we also investigate the fifth-order six-wave mixing response. Third, we characterize the ultrafast phase dynamics of the nonlinear emission using interferometric techniques with an unprecedented resolution of approximately 140 attoseconds. We find that effects arising from Coulomb correlation dominate the nonlinear optical response when the density of excitons falls below rm3times10 ^{11}cm^{-2}, the saturation density. Under these conditions, Coulomb interactions are unscreened and there exist two contributions to the multi-wave mixing emission. A prompt response from field scattering occurs via the phase-space filling effects of the Pauli exclusion principle, while a delayed response from polarization wave scattering occurs via the Coulomb interactions between excitons. In four-wave mixing, polarization wave scattering produces a non-exponential decay to the time-resolved signal and a corresponding non-linear phase evolution in the emitted pulse. In six-wave mixing, polarization wave
Eick, Dirk; Stabel, Silvia; Doerfler, Walter
1980-01-01
Spontaneously arising morphological revertants of the adenovirus type 12 (Ad12)-transformed hamster cell line T637 had been previously isolated, and it had been demonstrated that in these revertants varying amounts of the integrated Ad12 genome were eliminated from the host genome. In this report, the patterns of persistence of the viral genome in the revertants were analyzed in detail. In some of the revertant cell lines, F10, TR3, and TR7, all copies of Ad12 DNA integrated in line T637 were lost. In lines TR1, -2, -4 to -6, -8 to -10, and -13 to -16, only the right-hand portion of one Ad12 genome was preserved; it consisted of the intact right segment of Ad12 DNA and was integrated at the same site as in line T637. In revertant lines G12, TR11, and TR12, one Ad12 DNA and varying parts of a second viral DNA molecule persisted in the host genome. These patterns of persistence of Ad12 DNA molecules in different revertants supported a model for a mode of integration of Ad12 DNA in T637 hamster cells in which multiple (20 to 22) copies of the entire Ad12 DNA were serially arranged, separated from each other by stretches of cellular DNA. The occurrence of such revertants demonstrated that foreign DNA sequences could not only be acquired but could also be lost from eucaryotic genomes. There was very little, if any, expression of Ad12-specific DNA sequences in the revertant lines TR7 and TR12. Moreover, Ad12 DNA sequences which were found to be undermethylated in line T637 were completely methylated in the revertant cell lines G12, TR11, TR12, and TR2. These findings were consistent with the absence of T antigen from the revertant lines reported earlier. Hence it was conceivable that the expression of integrated viral DNA sequences was somehow dependent on their positions in the cellular genome. In cell line TR637, the early segments of Ad12 DNA were expressed and undermethylated; conversely, in the revertant lines G12, TR11, TR12, and TR2, the same segments appeared to
NASA Astrophysics Data System (ADS)
Tian, Y. P.; Wang, Y.; Jin, X. L.; Huang, Z. L.
2014-09-01
A nonlinear electromagnetic energy harvester directly powering a load resistance is considered in this manuscript. The nonlinearity includes the cubic stiffness and the unavoidable Coulomb friction, and the base excitation is confined to Gaussian white noise. Directly starting from the coupled equations, a novel procedure to evaluate the random responses and the mean output power is developed through the generalized harmonic transformation and the equivalent non-linearization technique. The dependence of the optimal ratio of the load resistance to the internal resistance and the associated optimal mean output power on the internal resistance of the coil is established. The principle of impedance matching is correct only when the internal resistance is infinity, and the optimal mean output power approaches an upper limit as the internal resistance is close to zero. The influence of the Coulomb friction on the optimal resistance ratio and the optimal mean output power is also investigated. It is proved that the Coulomb friction almost does not change the optimal resistance ratio although it prominently reduces the optimal mean output power.
Uncertainties of α-particle optical potential assessment around and below the Coulomb barrier
NASA Astrophysics Data System (ADS)
Avrigeanu, V.; Avrigeanu, M.; Mǎnǎilescu, C.
2017-06-01
A competition of the low-energy Coulomb excitation (CE) with the compound nucleus (CN) formation in α-induced reactions below the Coulomb barrier has recently been assumed in order to make possible the description of the latter as well as the α-particle emission by the same optical model (OM) potential. However, we show in the present work that the corresponding partial waves and integration radii provide evidence for the distinct account of the CE cross section and OM total-reaction cross section σR. Thus the largest contribution to CE cross section comes by far from partial waves larger than the ones contributing to the σR values. Finally, effects of statistical model parameters are comparatively discussed.
Transforming trauma healthcare delivery in rural areas by use of an integrated call center
Agrawal, Deepak
2012-01-01
Introduction: There is poor penetration of trauma healthcare delivery in rural areas. On the other hand, mobile penetration in India is now averaging 80% with most families having access to mobile phone. Aims and Objectives: The aim of this study was to assess the implementation and socioeconomic impact of a call center in providing healthcare delivery for patients with head and spinal injuries. Materials and Methods: This was a prospective observational study carried out over a 6-month period at a level I trauma Center in New Delhi, India. A nine-seater call center was outsourced to a private company and the hospital's electronic medical records were integrated with the call-center operations. The call center was given responsibility of maintaining appointments and scheduling clinics for the whole hospital as well as ensuring follow-up visits. Trained call-center staff handled simple patient queries and referred the rest via email to concerned doctors. A telephonic survey was done prior to the start of call-center operations and after 3 months to assess for user satisfaction. Results: The initial cost of outsourcing the call center was Rs 1.6 lakhs (US$ 4000), with a recurring cost of Rs 80,000 (US$ 2000) per month. A total of 484 patients were admitted in the department of Neurosurgery during the study period. Of these, 63% (n=305) were from rural areas. Patients’ overall experience for clinic visits improved markedly following implementation of call center. Patient satisfaction for follow-up visits increased from a mean of 32-96%. Ninety-five percent patients reported a significant decrease in waiting time in clinics 80.4% reporting improved doctor-patient interaction. A total of 52 visits could be postponed/cancelled for patients living in far flung areas resulting in major socioeconomic benefits to these families. Conclusions: As shown by our case study, call centers have the potential to revolutionize delivery of trauma healthcare to rural areas in an
Analytic evaluation of two-center molecular integrals
NASA Technical Reports Server (NTRS)
Tai, H.
1986-01-01
By using the Fourier-transform technique, the explicit expressions for the one-electron - two-center overlap integrals of Slater-type atomic orbitals up to 3d are derived. The final expressions are analytic, simple, and independent of local coordinates. Furthermore, they do not contain the nonclosed-form of exponential integrals which were presented in expressions given in earlier work. It is shown that the two-electron - two-center Coulomb integrals, as well as the hybrid integrals, can simply be expressed in terms of these integrals. The numerical instability arising from the situation in which the exponents of the two orbitals are almost equal is discussed, and a solution for this problem based on a Taylor-series expansion of the integral is suggested.
Classical Coulomb blockade of a silicon nanowire dot
NASA Astrophysics Data System (ADS)
Huang, Shaoyun; Fukata, Naoki; Shimizu, Maki; Yamaguchi, Tomohiro; Sekiguchi, Takashi; Ishibashi, Koji
2008-05-01
Single electron transistors (SETs) have been fabricated with an individual n-type single-crystal silicon nanowire (SiNW) that was grown by a catalytic chemical vapor deposition technique, and their transport properties have been measured in low temperatures. The SiNW-SET in the present work exhibited well pronounced Coulomb oscillations in a wide gate voltage range from -10to10V, featuring in uniform peak height, uniform full width at half maximum, and equidistant peak spacing. The charging energy turned out to be 64μeV. The temperature dependence of Coulomb oscillations revealed that the dot worked within the classical Coulomb blockade model.
Positron scattering from hydrogen atom with screened Coulomb potentials
Ghoshal, Arijit; Nayek, Sujay; Kamali, M. Z. M.; Ratnavelu, K.
2014-03-05
Elastic positron-hydrogen collisions with screened Coulomb potentials have been investigated using a second-order distorted wave Born approximation in the momentum space. Two types of potentials have been considered, namely, static screened Coulomb potential and exponential cosine-screened Coulomb potential. Using a simple variationally determined hydrogenic wave function it has been possible to obtain the scattering amplitude in a closed form. A detailed study has been made on the differential and total cross sections in the energy range 20–300 eV.
Verification of Coulomb order in a storage ring
Hasse, Rainer W.
1999-12-10
We verify theoretically that the anomalous longitudinal temperature reduction of strongly electron cooled heavy ions in the ESR at very low density is explained by the fact that there is no intrabeam scattering and that the particles by their Coulomb repulsion cannot pass each other any more. At the achievable momentum spreads Coulomb order is reached at particle distances of the order of centimeters. It is also shown that under the given experimental conditions in the proton NAP-M experiment of 1980 intrabeam heating counteracts Coulomb order.
Verification of Coulomb Order in a Storage Ring
Rainer W. Hasse
1999-12-31
We verify theoretically that the anomalous longitudinal temperature reduction of strongly electron cooled heavy ions in the ESR at very low density is explained by the fact that there is no intrabeam scattering and that the particles by their Coulomb repulsion cannot pass each other any more. At the achievable momentum spreads Coulomb order is reached at particle distances of the order of centimeters. It is also shown that under the given experimental conditions in the proton NAP-M experiment of 1980 intrabeam heating counteracts Coulomb order.
Coulomb crystal as a detector in electron impact ionization experiment
NASA Astrophysics Data System (ADS)
Klosowski, Lukasz; Piwinski, Mariusz; Wojtewicz, Szymon; Lisak, Daniel; Dziczek, Darek; Chwirot, Stanislaw
2016-09-01
Ensembles of ions in trap at sufficiently low temperature can form a structure called Coulomb crystal. Some species of such ions can be optically cooled and observed using CCD camera. Number of ions composing the crystal can be determined with high accuracy. Other, invisible species of ions can be sympathetically cooled and detected indirectly by observation of their influence on visible ones. Thus, the efficiency of ionization processes leading to Coulomb crystal formation can be determined. We present preliminary results for electron-impact-ionized molecules forming a multi-species Coulomb crystal in a linear segmented Paul trap together with atomic calcium ions.
Characterizing intra-exciton Coulomb scattering in terahertz excitations
Zybell, S.; Eßer, F.; Helm, M.; Bhattacharyya, J.; Winnerl, S.; Schneider, H.; Schneebeli, L.; Böttge, C. N.; Kira, M.; Koch, S. W.; Andrews, A. M.; Strasser, G.
2014-11-17
An intense terahertz field is applied to excite semiconductor quantum wells yielding strong non-equilibrium exciton distributions. Even though the relaxation channels involve a complicated quantum kinetics of Coulomb and phonon effects, distinct relaxation signatures of Coulomb scattering are identified within time-resolved photoluminescence by comparing the experiment with a reduced model that contains all relevant microscopic processes. The analysis uncovers a unique time scale for the Coulomb scattering directly from experiments and reveals the influence of phonon relaxation as well as radiative decay.
Coulomb field effect on plasma focusing and wake field acceleration
Amatuni, A.Ts.; Elbakian, S.S.; Sekhpossian, E.V.
1993-11-01
It is shown that the fields generated by relativistic electron (positron) bunches moving in overdense cold plasma have two components -- wake and Coulomb. The existence of the Coulomb component is caused by the absence of the Debay screening of the charge moving in plasma with the velocity greater than the thermal velocity of the plasma electrons. It is shown that at some conditions the contribution of the Coulomb component to focusing and self-focusing of the electron (positron) bunches, and wake field generation could be essential. This conclusion is valid for different descriptions of cold plasma-relativistic electron bunch system.
Safouhi, Hassan . E-mail: hassan.safouhi@ualberta.ca; Berlu, Lilian
2006-07-20
Molecular overlap-like quantum similarity measurements imply the evaluation of overlap integrals of two molecular electronic densities related by Dirac delta function. When the electronic densities are expanded over atomic orbitals using the usual LCAO-MO approach (linear combination of atomic orbitals), overlap-like quantum similarity integrals could be expressed in terms of four-center overlap integrals. It is shown that by introducing the Fourier transform of delta Dirac function in the integrals and using the Fourier transform approach combined with the so-called B functions, one can obtain analytic expressions of the integrals under consideration. These analytic expressions involve highly oscillatory semi-infinite spherical Bessel functions, which are the principal source of severe numerical and computational difficulties. In this work, we present a highly efficient algorithm for a fast and accurate numerical evaluation of these multicenter overlap-like quantum similarity integrals over Slater type functions. This algorithm is based on the SD-bar approach due to Safouhi. Recurrence formulae are used for a better control of the degree of accuracy and for a better stability of the algorithm. The numerical result section shows the efficiency of our algorithm, compared with the alternatives using the one-center two-range expansion method, which led to very complicated analytic expressions, the epsilon algorithm and the nonlinear D-bar transformation.
Electron attraction mediated by Coulomb repulsion.
Hamo, A; Benyamini, A; Shapir, I; Khivrich, I; Waissman, J; Kaasbjerg, K; Oreg, Y; von Oppen, F; Ilani, S
2016-07-21
One of the defining properties of electrons is their mutual Coulomb repulsion. However, in solids this basic property may change; for example, in superconductors, the coupling of electrons to lattice vibrations makes the electrons attract one another, leading to the formation of bound pairs. Fifty years ago it was proposed that electrons can be made attractive even when all of the degrees of freedom in the solid are electronic, by exploiting their repulsion from other electrons. This attraction mechanism, termed 'excitonic', promised to achieve stronger and more exotic superconductivity. Yet, despite an extensive search, experimental evidence for excitonic attraction has yet to be found. Here we demonstrate this attraction by constructing, from the bottom up, the fundamental building block of the excitonic mechanism. Our experiments are based on quantum devices made from pristine carbon nanotubes, combined with cryogenic precision manipulation. Using this platform, we demonstrate that two electrons can be made to attract each other using an independent electronic system as the 'glue' that mediates attraction. Owing to its tunability, our system offers insights into the underlying physics, such as the dependence of the emergent attraction on the underlying repulsion, and the origin of the pairing energy. We also demonstrate transport signatures of excitonic pairing. This experimental demonstration of excitonic pairing paves the way for the design of exotic states of matter.
Coulomb gauge model for hidden charm tetraquarks
NASA Astrophysics Data System (ADS)
Xie, W.; Mo, L. Q.; Wang, Ping; Cotanch, Stephen R.
2013-08-01
The spectrum of tetraquark states with hidden charm is studied within an effective Coulomb gauge Hamiltonian approach. Of the four independent color schemes, two are investigated, the (qcbar)1(cqbar)1 singlet-singlet (molecule) and the (qc)3(qbarcbar)3 triplet-triplet (diquark), for selected JPC states using a variational method. The predicted masses of triplet-triplet tetraquarks are roughly a GeV heavier than the singlet-singlet states. There is also an interesting flavor dependence with (qqbar)1 (ccbar1) states about half a GeV lighter than (qcbar)1(qbarc)1. The lightest 1++ and 1-- predictions are in agreement with the observed X (3872) and Y (4008) masses suggesting they are molecules with ωJ / ψ and ηhc, rather than D*Dbar* and DDbar, type structure, respectively. Similarly, the lightest isovector 1++ molecule, having a ρJ / ψ flavor composition, has mass near the recently observed charged Zc (3900) value. These flavor configurations are consistent with observed X, Y and Zc decays to ππJ / ψ.
Deep inelastic scattering near the Coulomb barrier
Gehring, J.; Back, B.; Chan, K.
1995-08-01
Deep inelastic scattering was recently observed in heavy ion reactions at incident energies near and below the Coulomb barrier. Traditional models of this process are based on frictional forces and are designed to predict the features of deep inelastic processes at energies above the barrier. They cannot be applied at energies below the barrier where the nuclear overlap is small and friction is negligible. The presence of deep inelastic scattering at these energies requires a different explanation. The first observation of deep inelastic scattering near the barrier was in the systems {sup 124,112}Sn + {sup 58,64}Ni by Wolfs et al. We previously extended these measurements to the system {sup 136}Xe + {sup 64}Ni and currently measured the system {sup 124}Xe + {sup 58}Ni. We obtained better statistics, better mass and energy resolution, and more complete angular coverage in the Xe + Ni measurements. The cross sections and angular distributions are similar in all of the Sn + Ni and Xe + Ni systems. The data are currently being analyzed and compared with new theoretical calculations. They will be part of the thesis of J. Gehring.
Multilevel Monte Carlo simulation of Coulomb collisions
Rosin, M. S.; Ricketson, L. F.; Dimits, A. M.; ...
2014-05-29
We present a new, for plasma physics, highly efficient multilevel Monte Carlo numerical method for simulating Coulomb collisions. The method separates and optimally minimizes the finite-timestep and finite-sampling errors inherent in the Langevin representation of the Landau–Fokker–Planck equation. It does so by combining multiple solutions to the underlying equations with varying numbers of timesteps. For a desired level of accuracy ε , the computational cost of the method is O(ε–2) or (ε–2(lnε)2), depending on the underlying discretization, Milstein or Euler–Maruyama respectively. This is to be contrasted with a cost of O(ε–3) for direct simulation Monte Carlo or binary collision methods.more » We successfully demonstrate the method with a classic beam diffusion test case in 2D, making use of the Lévy area approximation for the correlated Milstein cross terms, and generating a computational saving of a factor of 100 for ε=10–5. Lastly, we discuss the importance of the method for problems in which collisions constitute the computational rate limiting step, and its limitations.« less
Multilevel Monte Carlo simulation of Coulomb collisions
Rosin, M. S.; Ricketson, L. F.; Dimits, A. M.; Caflisch, R. E.; Cohen, B. I.
2014-05-29
We present a new, for plasma physics, highly efficient multilevel Monte Carlo numerical method for simulating Coulomb collisions. The method separates and optimally minimizes the finite-timestep and finite-sampling errors inherent in the Langevin representation of the Landau–Fokker–Planck equation. It does so by combining multiple solutions to the underlying equations with varying numbers of timesteps. For a desired level of accuracy ε , the computational cost of the method is O(ε^{–2}) or (ε^{–2}(lnε)^{2}), depending on the underlying discretization, Milstein or Euler–Maruyama respectively. This is to be contrasted with a cost of O(ε^{–3}) for direct simulation Monte Carlo or binary collision methods. We successfully demonstrate the method with a classic beam diffusion test case in 2D, making use of the Lévy area approximation for the correlated Milstein cross terms, and generating a computational saving of a factor of 100 for ε=10^{–5}. Lastly, we discuss the importance of the method for problems in which collisions constitute the computational rate limiting step, and its limitations.
Coulomb glass in the random phase approximation
NASA Astrophysics Data System (ADS)
Basylko, S. A.; Onischouk, V. A.; Rosengren, A.
2002-01-01
A three-dimensional model of the electrons localized on randomly distributed donor sites of density n and with the acceptor charge uniformly smeared on these sites, -Ke on each, is considered in the random phase approximation (RPA). For the case K=1/2 the free energy, the density of the one-site energies (DOSE) ɛ, and the pair OSE correlators are found. In the high-temperature region (e2n1/3/T)<1 (T is the temperature) RPA energies and DOSE are in a good agreement with the corresponding data of Monte Carlo simulations. Thermodynamics of the model in this region is similar to the one of an electrolyte in the regime of Debye screening. In the vicinity of the Fermi level μ=0 the OSE correlations, depending on sgn(ɛ1.ɛ2) and with very slow decoupling law, have been found. The main result is that even in the temperature range where the energy of a Coulomb glass is determined by Debye screening effects, the correlations of the long-range nature between the OSE still exist.
Multilevel Monte Carlo simulation of Coulomb collisions
Rosin, M.S.; Ricketson, L.F.; Dimits, A.M.; Caflisch, R.E.; Cohen, B.I.
2014-10-01
We present a new, for plasma physics, highly efficient multilevel Monte Carlo numerical method for simulating Coulomb collisions. The method separates and optimally minimizes the finite-timestep and finite-sampling errors inherent in the Langevin representation of the Landau–Fokker–Planck equation. It does so by combining multiple solutions to the underlying equations with varying numbers of timesteps. For a desired level of accuracy ε, the computational cost of the method is O(ε{sup −2}) or O(ε{sup −2}(lnε){sup 2}), depending on the underlying discretization, Milstein or Euler–Maruyama respectively. This is to be contrasted with a cost of O(ε{sup −3}) for direct simulation Monte Carlo or binary collision methods. We successfully demonstrate the method with a classic beam diffusion test case in 2D, making use of the Lévy area approximation for the correlated Milstein cross terms, and generating a computational saving of a factor of 100 for ε=10{sup −5}. We discuss the importance of the method for problems in which collisions constitute the computational rate limiting step, and its limitations.
Femtosecond Laser-Induced Coulomb Explosion Imaging
NASA Astrophysics Data System (ADS)
Karimi, Reza; Liu, Wing-Ki; Sanderson, Joseph
2016-07-01
We review recent progress in the field of Coulomb imaging using femtosecond laser pulses of variable length, referred to as Femtosecond Multiple Pulse Length Spectroscopy (FEMPULS). This method introduces a multi-dimensional approach to the study of the molecular dynamics of the multiply ionized triatomic molecules: CO2, OCS, and N2O. We describe the experimental setup used and the approaches needed to optimize the multi-particle detection, coincidence technique. The results show the degree of high resolution imaging which can be achieved with few cycle pulses, and how the onset of charge resonance enhanced ionization (CREI) can be observed as pulse length is increased. By coupling pulse length variation with Dalitz and Newton plotting techniques, stepwise processes can be identified for all three molecules, giving insight into the dynamics, particularly on the 3+ state, which has been revealed as the doorway state to CREI. Finally, in the case of OCS, pulse length variation is shown to have the potential as a control mechanism, as it modulates the ratio of stepwise to concerted processes.
Coulomb gauge ghost Dyson-Schwinger equation
NASA Astrophysics Data System (ADS)
Watson, P.; Reinhardt, H.
2010-12-01
A numerical study of the ghost Dyson-Schwinger equation in Coulomb gauge is performed and solutions for the ghost propagator found. As input, lattice results for the spatial gluon propagator are used. It is shown that in order to solve completely, the equation must be supplemented by a nonperturbative boundary condition (the value of the inverse ghost propagator dressing function at zero momentum), which determines if the solution is critical (zero value for the boundary condition) or subcritical (finite value). The various solutions exhibit a characteristic behavior where all curves follow the same (critical) solution when going from high to low momenta until forced to freeze out in the infrared to the value of the boundary condition. The renormalization is shown to be largely independent of the boundary condition. The boundary condition and the pattern of the solutions can be interpreted in terms of the Gribov gauge-fixing ambiguity. The connection to the temporal gluon propagator and the infrared slavery picture of confinement is explored.
Electron attraction mediated by Coulomb repulsion
NASA Astrophysics Data System (ADS)
Hamo, A.; Benyamini, A.; Shapir, I.; Khivrich, I.; Waissman, J.; Kaasbjerg, K.; Oreg, Y.; von Oppen, F.; Ilani, S.
2016-07-01
One of the defining properties of electrons is their mutual Coulomb repulsion. However, in solids this basic property may change; for example, in superconductors, the coupling of electrons to lattice vibrations makes the electrons attract one another, leading to the formation of bound pairs. Fifty years ago it was proposed that electrons can be made attractive even when all of the degrees of freedom in the solid are electronic, by exploiting their repulsion from other electrons. This attraction mechanism, termed ‘excitonic’, promised to achieve stronger and more exotic superconductivity. Yet, despite an extensive search, experimental evidence for excitonic attraction has yet to be found. Here we demonstrate this attraction by constructing, from the bottom up, the fundamental building block of the excitonic mechanism. Our experiments are based on quantum devices made from pristine carbon nanotubes, combined with cryogenic precision manipulation. Using this platform, we demonstrate that two electrons can be made to attract each other using an independent electronic system as the ‘glue’ that mediates attraction. Owing to its tunability, our system offers insights into the underlying physics, such as the dependence of the emergent attraction on the underlying repulsion, and the origin of the pairing energy. We also demonstrate transport signatures of excitonic pairing. This experimental demonstration of excitonic pairing paves the way for the design of exotic states of matter.
NASA Astrophysics Data System (ADS)
Bonhivers, Jean-Christophe
The increase in production of goods over the last decades has led to the need for improving the management of natural resources management and the efficiency of processes. As a consequence, heat integration methods for industry have been developed. These have been successful for the design of new plants: the integration principles are largely employed, and energy intensity has dramatically decreased in many processes. Although progress has also been achieved in integration methods for retrofit, these methods still need further conceptual development. Furthermore, methodological difficulties increase when trying to retrofit heat exchange networks that are closely interrelated to water networks, such as the case of pulp and paper mills. The pulp and paper industry seeks to increase its profitability by reducing production costs and optimizing supply chains. Recent process developments in forestry biorefining give this industry the opportunity for diversification into bio-products, increasing potential profit margins, and at the same time modernizing its energy systems. Identification of energy strategies for a mill in a changing environment, including the possibility of adding a biorefinery process on the industrial site, requires better integration methods for retrofit situations. The objective of this thesis is to develop an energy integration method for the retrofit of industrial systems and the transformation of pulp and paper mills, ant to demonstrate the method in case studies. Energy is conserved and degraded in a process. Heat can be converted into electricity, stored as chemical energy, or rejected to the environment. A systematic analysis of successive degradations of energy between the hot utilities until the environment, through process operations and existing heat exchangers, is essential in order to reduce the heat consumption. In this thesis, the "Bridge Method" for energy integration by heat exchanger network retrofit has been developed. This method
USDA-ARS?s Scientific Manuscript database
Plant Transformation Technologies is a comprehensive, authoritative book focusing on cutting-edge plant biotechnologies, offering in-depth, forward-looking information on methods for controlled and accurate genetic engineering. In response to ever-increasing pressure for precise and efficient integr...
ERIC Educational Resources Information Center
Stonemeier, Jennifer; Trader, Barbara; Kingston, Mary; Richards, Curtis; Blank, Rolf; East, Bill
2014-01-01
The SWIFT Center (Schoolwide Integrated Framework for Transformation) is an initiative to bring about educational equity district by district until all students excel, including students with the most profound needs. As the national technical assistance center to build schoolwide inclusive practices to improve academic and behavioral outcomes for…
Zhang Songbin; Wang Jianguo; Janev, R. K.
2010-01-15
The effects of Coulomb interaction screening on electron-hydrogen atom excitation in the n=2 threshold region are investigated by using the R-matrix method with pseudostates. The interaction screening lifts the l degeneracy of n=2 Coulomb energy level, producing two distinct thresholds for 2s and 2p states. The phenomenon of transformation of {sup 1,3}P and {sup 1}D Feshbach resonances into shape-type resonances is observed when they pass across the 2s and 2p threshold, respectively, as the interaction screening increases. It is shown that this resonance transformation leads to dramatic effects in the 1s->2s and 1s->2p excitation collision strengths in the n=2 threshold collision energy region.
Lanzarotta, Adam; Falconer, Travis; McCauley, Heather; Lorenz, Lisa; Albright, Douglas; Crowe, John; Batson, JaCinta
2017-05-01
Analytes that co-elute and yield nearly identical electron ionization (EI) mass spectra, as well as analytes that yield non-specific EI fragmentation patterns, have been identified using fully integrated gas chromatography with direct deposit Fourier transform infrared detection and mass spectrometric detection (GC/FT-IR/MS). While the IR detector proved to be more selective for identifying analytes such as synthetic cannabinoids and weight loss drugs, it was limited by a relatively high detection limit of 8.4 parts per million (ppm) for non-targeted identification of sibutramine based on a single injection but was reduced to 840 parts per billion (ppb) for targeted identification of sibutramine by redepositing ten injections along the same track. The MS detector was less selective for identifying these analytes but yielded non-targeted and targeted detection limits of approximately 84 ppb and 8.4 ppb, respectively, which corresponded to a 100-fold advantage compared to the IR detector. Overall, the results of this study demonstrate that the advantages of each detector compensate for the limitations of the other, which allows a wider range of analytes and concentrations to be examined using a fully integrated GC/FT-IR/MS instrument compared to what can be examined using GC/IR or GC/MS independently. Not only does this approach reduce consumption of laboratory resources and time, it provides IR and MS information on the same sample, which is important for forensic analyses that require data from two or more orthogonal techniques to make an identification.
Indirect Coulomb energy for two-dimensional atoms
Benguria, Rafael D.; Tusek, Matej
2012-09-15
In this paper we provide a family of lower bounds on the indirect Coulomb energy for atomic and molecular systems in two dimensions in terms of a functional of the single particle density with gradient correction terms.
Multifragmentation: Surface and Coulomb instabilities of sheets, bubbles, and donuts
Moretto, L.G.; Tso, Kin; Wozniak, G.J.
1993-08-01
Disks, bubbles, and donuts have been observed in dynamical calculations of heavy ion collisions. These shapes are subject to a variety of surface and Coulomb instabilities. These instabilities are identified and analyzed in terms of their relevance to multifragmentation.
Constants of motion in deformed oscillator and Coulomb systems
NASA Astrophysics Data System (ADS)
Hakobyan, Tigran; Nersessian, Armen; Shmavonyan, Hovhannes
2017-03-01
In this note we propose a unified description for the constants of motion for superintegrable deformations of the oscillator and Coulomb systems on N-dimensional Euclidean space, sphere and hyperboloid.
Thermodynamic properties of the magnetized Coulomb crystal lattices
NASA Astrophysics Data System (ADS)
Kozhberov, A. A.
2016-08-01
It is thought that Coulomb crystals of ions with hexagonal close-packed lattice may form in the crust of strongly-magnetized neutron stars (magnetars). In this work we are trying to verify this prediction assuming that the direction of the magnetic field corresponds to the minimum of the zero-point energy. We also continue a detailed study of vibration modes and thermodynamic properties of magnetized Coulomb crystals in a wide range of temperatures and magnetic fields. It is demonstrated that the total Helmholtz free energy of the body-centered cubic Coulomb crystal is always lower than that of the Coulomb crystal with hexagonal close-packed or face-centered cubic lattice, which casts doubt on the hypothesis above.
Everett, Anita S; Reese, Jennifer; Coughlin, Janelle; Finan, Patrick; Smith, Michael; Fingerhood, Michael; Berkowitz, Scott; Young, J Hunter; Johnston, Diedre; Dunbar, Linda; Zollinger, Raymond; Ju, Jin; Reuland, Melissa; Strain, Eric C; Lyketsos, Constantine
2014-12-01
Health systems in the USA have received a mandate to improve quality while reining in costs. Several opportunities have been created to stimulate this transformation. This paper describes the design, early implementation and lessons learned for the behavioural components of the John Hopkins Community Health Partnership (J-CHiP) programme. J-CHiP is designed to improve health outcomes and reduce the total healthcare costs of a group of high healthcare use patients who are insured by the government-funded health insurance programmes, Medicaid and Medicare. These patients have a disproportionately high prevalence of depression, other psychiatric conditions, and unhealthy behaviours that could be addressed with behavioural interventions. The J-CHiP behavioural intervention is based on integrated care models, which include embedding mental health professionals into primary sites. A four-session behaviour-based protocol was developed to motivate self-efficacy through illness management skills. In addition to staff embedded in primary care, the programme design includes expedited access to specialist psychiatric services as well as a community outreach component that addresses stigma. The progress and challenges involved with developing this programme over a relatively short period of time are discussed.
Li, Fuzhong
2014-01-01
Tai Ji Quan, developed as a martial art, has traditionally served multiple purposes, including self-defense, competition/performance, and health promotion. With respect to health, the benefits historically and anecdotally associated with Tai Ji Quan are now being supported by scientific and clinical research, with mounting evidence indicating its potential value in preventing and managing various diseases and improving well-being and quality of life in middle-aged and older adults. The research findings produced to date have both public health significance and clinical relevance. However, because of its roots in the martial arts, transforming traditional Tai Ji Quan movements and training approaches into contemporary therapeutic programs and functional applications is needed to maximize its ultimate utility. This paper addresses this issue by introducing Tai Ji Quan: Moving for Better Balance, a functional therapy that involves the use of Tai Ji Quan principles and Yang-style-based movements to form an innovative, contemporary therapeutic approach that integrates motor, sensory, and cognitive components to improve postural control, gait, and mobility for older adults and those who have neurodegenerative movement impairments. It provides a synergy of traditional and contemporary Tai Ji Quan practice with the ultimate goal of improving balance and gait, enhancing performance of daily functional tasks, and reducing incidence of falls among older adults. PMID:25126445
Li, Fuzhong
2014-03-01
Tai Ji Quan, developed as a martial art, has traditionally served multiple purposes, including self-defense, competition/performance, and health promotion. With respect to health, the benefits historically and anecdotally associated with Tai Ji Quan are now being supported by scientific and clinical research, with mounting evidence indicating its potential value in preventing and managing various diseases and improving well-being and quality of life in middle-aged and older adults. The research findings produced to date have both public health significance and clinical relevance. However, because of its roots in the martial arts, transforming traditional Tai Ji Quan movements and training approaches into contemporary therapeutic programs and functional applications is needed to maximize its ultimate utility. This paper addresses this issue by introducing Tai Ji Quan: Moving for Better Balance, a functional therapy that involves the use of Tai Ji Quan principles and Yang-style-based movements to form an innovative, contemporary therapeutic approach that integrates motor, sensory, and cognitive components to improve postural control, gait, and mobility for older adults and those who have neurodegenerative movement impairments. It provides a synergy of traditional and contemporary Tai Ji Quan practice with the ultimate goal of improving balance and gait, enhancing performance of daily functional tasks, and reducing incidence of falls among older adults.
A New Hybrid STEP/Coulomb model for Aftershock Forecasting
NASA Astrophysics Data System (ADS)
Steacy, S.; Jimenez, A.; Gerstenberger, M.
2014-12-01
Aftershock forecasting models tend to fall into two classes - purely statistical approaches based on clustering, b-value, and the Omori-Utsu law; and Coulomb rate-state models which relate the forecast increase in rate to the magnitude of the Coulomb stress change. Recently, hybrid models combining physical and statistical forecasts have begun to be developed, for example by Bach and Hainzl (2012) and Steacy et al. (2013). The latter approach combined Coulomb stress patterns with the STEP (short-term earthquake probability) model by redistributing expected rate from areas with decreased stress to regions where the stress had increased. The chosen 'Coulomb Redistribution Parameter' (CRP) was 0.93, based on California earthquakes, which meant that 93% of the total rate was expected to occur where the stress had increased. The model was tested against the Canterbury sequence and the main result was that the new model performed at least as well as, and often better than, STEP when tested against retrospective data but that STEP was generally better in pseudo-prospective tests that involved data actually available within the first 10 days of each event of interest. The authors suggested that the major reason for this discrepancy was uncertainty in the slip models and, particularly, in the geometries of the faults involved in each complex major event. Here we develop a variant of the STEP/Coulomb model in which the CRP varies based on the percentage of aftershocks that occur in the positively stressed areas during the forecast learning period. We find that this variant significantly outperforms both STEP and the previous hybrid model in almost all cases, even when the input Coulomb model is quite poor. Our results suggest that this approach might be more useful than Coulomb rate-state when the underlying slip model is not well constrained due to the dependence of that method on the magnitude of the Coulomb stress change.
Uniform derivation of Coulomb collisional transport thanks to Debye shielding
NASA Astrophysics Data System (ADS)
Escande, Dominique; Elskens, Yves; Doveil, Fabrice
2016-10-01
The effective potential acting on particles in plasmas being essentially the Debye-shielded Coulomb potential, the particles collisional transport in thermal equilibrium is calculated for all impact parameters b, with a convergent expression reducing to Rutherford scattering for small b, in agreement with both usual expressions holding for large b and small b. No cutoff at the Debye length scale is needed, and the Coulomb logarithm is only slightly modified.
Coulomb-exchange contribution to proton-nucleus scattering
Arellano, H.F.; Love, W.G. )
1992-02-01
A scheme for including the Coulomb-exchange contribution in momentum-space calculations of proton-nucleus scattering is presented. The main feature of this approach is a careful treatment of the singular two-body Coulomb potential when the Fermi motion of the bound protons is treated explicitly as required by full-folding calculations of microscopic optical potentials. Analytic expressions are presented and applications are discussed.
Aftershock triggering by complete Coulomb stress changes
Kilb, Debi; Gomberg, J.; Bodin, P.
2002-01-01
We examine the correlation between seismicity rate change following the 1992, M7.3, Landers, California, earthquake and characteristics of the complete Coulomb failure stress (CFS) changes (??CFS(t)) that this earthquake generated. At close distances the time-varying "dynamic" portion of the stress change depends on how the rupture develops temporally and spatially and arises from radiated seismic waves and from permanent coseismic fault displacement. The permanent "static" portion (??CFS) depends only on the final coseismic displacement. ??CFS diminishes much more rapidly with distance than the transient, dynamic stress changes. A common interpretation of the strong correlation between ??CFS and aftershocks is that load changes can advance or delay failure. Stress changes may also promote failure by physically altering properties of the fault or its environs. Because it is transient, ??CFS(t) can alter the failure rate only by the latter means. We calculate both ??CFS and the maximum positive value of ??CFS(t) (peak ??CFS(t)) using a reflectivity program. Input parameters are constrained by modeling Landers displacement seismograms. We quantify the correlation between maps of seismicity rate changes and maps of modeled ??CFS and peak ??CFS(t) and find agreement for both models. However, rupture directivity, which does not affect ??CFS, creates larger peak ??CFS(t) values northwest of the main shock. This asymmetry is also observed in seismicity rate changes but not in ??CFS. This result implies that dynamic stress changes are as effective as static stress changes in triggering aftershocks and may trigger earthquakes long after the waves have passed.
NASA Astrophysics Data System (ADS)
Kagan, M. Yu.; Val'kov, V. V.; Aksenov, S. V.
2017-01-01
We present an analytical and numerical investigation of the spectral and transport properties of a quadruple quantum-dot (QQD) structure which is one of the popular low-dimensional systems in the context of fundamental quantum physics study, future electronic applications, and quantum calculations. The density of states, occupation numbers, and conductance of the structure were analyzed using the nonequilibrium Green's functions in the tight-binding approach and the equation-of-motion method. In particular the anisotropy of hopping integrals and on-site electron energies as well as the effects of the finite intra- and interdot Coulomb interactions were investigated. It was found out that the anisotropy of the kinetic processes in the system leads to the Fano-Feshbach asymmetrical peak. We demonstrated that the conductance of the QQD device has a wide insulating band with steep edges separating triple-peak structures if the intradot Coulomb interactions are taken into account. The interdot Coulomb correlations between the central QDs result in the broadening of this band and the occurrence of an additional band with low conductance due to the Fano antiresonances. It was shown that in this case the conductance of the anisotropic QQD device can be dramatically changed by tuning the anisotropy of on-site electron energies.
Ultrafast dynamics of Coulomb correlated excitons in GaAs quantum wells
Mycek, M.A. |
1995-12-01
The author measures the transient nonlinear optical response of room temperature excitons in gallium arsenide quantum wells via multi-wave mixing experiments. The dynamics of the resonantly excited excitons is directly reflected by the ultrafast decay of the induced nonlinear polarization, which radiates the detected multi-wave mixing signal. She characterizes this ultrafast coherent emission in both amplitude and phase, using time- and frequency-domain measurement techniques, to better understand the role of Coulomb correlation in these systems. To interpret the experimental results, the nonlinear optical response of a dense medium is calculated using a model including Coulomb interaction. She contributes three new elements to previous theoretical and experimental studies of these systems. First, surpassing traditional time-integrated measurements, she temporally resolves the amplitude of the ultrafast coherent emission. Second, in addition to measuring the third-order four-wave mixing signal, she also investigates the fifth-order six-wave mixing response. Third, she characterizes the ultrafast phase dynamics of the nonlinear emission using interferometric techniques with an unprecedented resolution of approximately 140 attoseconds. The author finds that effects arising from Coulomb correlation dominate the nonlinear optical response when the density of excitons falls below 3 {times} 10{sup 11} cm{sup {minus}2}, the saturation density. These signatures of Coulomb correlation are investigated for increasing excitation density to gradually screen the interactions and test the validity of the model for dense media. The results are found to be qualitatively consistent with both the predictions of the model and with numerical solutions to the semiconductor Bloch equations. Importantly, the results also indicate current experimental and theoretical limitations, which should be addressed in future research.
Yao, Jia-Long; Tomes, Sumathi; Gleave, Andrew P
2013-05-01
Apple acetolactate synthase mutants were generated by site-specific mutagenesis and successfully used as selection marker in tobacco and apple transformation. T-DNA/Apple genome junctions were analysed using genome-walking PCR and sequencing. An Agrobacterium-mediated genetic transformation system was developed for apple (Malus × domestica), using mutants of apple acetolactate synthase (ALS) as a selectable marker. Four apple ALS mutants were generated by site-specific mutagenesis and subsequently cloned under the transcriptional control of the CaMV 35S promoter and ocs 3' terminator, in a pART27-derived plant transformation vector. Three of the four mutations were found to confer resistance to the herbicide Glean(®), containing the active agent chlorsulfuron, in tobacco (Nicotiana tabacum) transformation. In apple transformation, leaf explants infected with Agrobacterium tumefaciens EHA105 containing one of the three ALS mutants resulted in the production of shoots on medium containing 2-8 μg L(-1) Glean(®), whilst uninfected wild-type explants failed to regenerate shoots or survive on medium containing 1 and 3 μg L(-1) Glean(®), respectively. Glean(®)-resistant, regenerated shoots were further multiplied and rooted on medium containing 10 μg L(-1) Glean(®). The T-DNA and apple genome-DNA junctions from eight rooted transgenic apple plants were analysed using genome-walking PCR amplification and sequencing. This analysis confirmed T-DNA integration into the apple genome, identified the genome integration sites and revealed the extent of any vector backbone integration, T-DNA rearrangements and deletions of apple genome DNA at the sites of integration.
Coulomb stress transfer and tectonic loading preceding the 2002 Denali fault earthquake
Bufe, C.G.
2006-01-01
Pre-2002 tectonic loading and Coulomb stress transfer are modeled along the rupture zone of the M 7.9 Denali fault earthquake (DFE) and on adjacent segments of the right-lateral Denali-Totschunda fault system in central Alaska, using a three-dimensional boundary-element program. The segments modeled closely follow, for about 95??, the arc of a circle of radius 375 km centered on an inferred asperity near the northeastern end of the intersection of the Patton Bay fault with the Alaskan megathrust under Prince William Sound. The loading model includes slip of 6 mm/yr below 12 km along the fault system, consistent with rotation of the Wrangell block about the asperity at a rate of about 1??/m.y. as well as slip of the Pacific plate at 5 cm/yr at depth along the Fairweather-Queen Charlotte transform fault system and on the Alaska megathrust. The model is consistent with most available pre-2002 Global Positioning System (GPS) displacement rate data. Coulomb stresses induced on the Denali-Totschunda fault system (locked above 12 km) by slip at depth and by transfer from the M 9.2 Prince William Sound earthquake of 1964 dominated the changing Coulomb stress distribution along the fault. The combination of loading (???70-85%) and coseismic stress transfer from the great 1964 earthquake (???15-30%) were the principal post-1900 stress factors building toward strike-slip failure of the northern Denali and Totschunda segments in the M 7.9 earthquake of November 2002. Postseismic stresses transferred from the 1964 earthquake may also have been a significant factor. The M 7.2-7.4 Delta River earthquake of 1912 (Carver et al., 2004) may have delayed or advanced the timing of the DFE, depending on the details and location of its rupture. The initial subevent of the 2002 DFE earthquake was on the 40-km Susitna Glacier thrust fault at the western end of the Denali fault rupture. The Coulomb stress transferred from the 1964 earthquake moved the Susitna Glacier thrust fault uniformly
Coulomb excitation of states in 238U
NASA Astrophysics Data System (ADS)
McGowan, F. K.; Milner, W. T.
1994-05-01
Twenty-two states in 238U have been observed with 18 MeV 4He ions on a thick target. Eight 2 + states between 966 and 1782 keV and three 3 - states are populated by direct E2 and E3, respectively. The remaining states are either weakly excited by multiple Coulomb excitation and /or populated by the γ-ray decay of the directly excited states. Spin assignments are based on γ-ray angular distributions. Reduced transition probabilities have been deduced from the γ-ray yields. The B(E2) values for excitation of the 2 + states range from 0.10 to 3.0 W.u. (281 W.u. for the first 2 + state). For the 3 states, the B(E3, 0 → 3 -) values are 7.1, 7.8, and 24.2 W.u. Several of the 2 + states have decay branches to the one-phonon states with B(E2) values between 27 and 56 W.u. which are an order of magnitude larger than the B(E2) values between the one- and zero-phonon states. This disagrees with our present understanding of collectivity in nuclei if these 2 + states are considered to be collective two-phonon excitations. However, the excitation energies of these 2 + states with respect to the one-phonon states are only 1.3 to 1.6. The B(E1) values for 17 transitions between the positive- and negative-parity states range between 10 -3 and 10 -7 W.u. The B(E1) branching ratios for many of these transitions have large deviations from the Alaga-rule predictions. These deviations can be understood by the strong Coriolis coupling between the states of the one-phonon octupole quadruplet in deformed nuclei. The general features of the experimental results for the B(E3) values are reproduced by the microscopic calculations of Neergård and Vogel when the Coriolis coupling between the states of the octupole quadruplet is included.
Coulomb excitation of states in 232Th
NASA Astrophysics Data System (ADS)
McGowan, F. K.; Milner, W. T.
1993-09-01
Twenty-five states in 232Th have been observed with 18 MeV 4He ions on a thick target. Eleven 2 + states between 774 and 1554 keV and three 3 - states are populated by direct E2 and E3, respectively. The remaining states are either weakly excited by multiple Coulomb excitation and/or populated by the decay of the directly excited states. Spin assignments are based on γ-ray angular distributions. Reduced transition probabilities have been deduced from the γ-ray yields. The B(E2) values for excitation of the 2 + states range from 0.024 to 3.5 W.u. (222 W.u. for the first 2 + state). For the 3 - states, the B(E3,0 → 3 -) values are 1.7, 11, and 24 W.u. A possible two-phonon state at 1554 keV, which is nearly harmonic, decays to four members of the one-phonon states, to the ground-state band, and to the K = 0 - octupole band. The B(E2) value for excitation of this state is 0.66 ± 0.05 W.u. and the B(E1) values for decay of this state are (2 and 6)×10 -4 W.u. The B(E2) values between two- and one-phonon vibrational states range between 16 and 53 W.u. which are an order of magnitude larger than the B(E2) values between the one- and zero-phonon states. This disagrees with our present understanding of collectivity in nuclei if this 2 + state is considered to be a collective two-phonon excitation. The 2 + states at 1477 and 1387 keV, which are also nearly harmonic, are possible candidates with two-phonon structure. The agreement between the experimental results and the microscopic calculations by Neergård and Vogel of the B(E3,0 → 3) for the 3 - members of the one-phonon octupole quadruplet is satisfactory when the Coriolis coupling between the states with K and K ± 1 is included. The B(E1) branching ratios for transitions from the 3 - and 1 - states to the ground-state band have large deviations from the Alaga-rule predictions. These deviations can be understood by the strong Coriolis coupling between the states of the octupole quadruplet in deformed nuclei.
NASA Astrophysics Data System (ADS)
Zhang, Jiancheng; Su, Tao; Li, Yanyan; Zheng, Jibin
2016-07-01
Long-time coherent integration is an effective means to improve the radar detection ability of high-speed maneuvering targets with jerk motion. However, the range migration (RM) and Doppler frequency migration (DFM) have a great impact on the integration performance. To overcome these problems, a unique method, called the second-order keystone transform modified integrated cubic phase function (SKT-MICPF), is proposed. In this method, the velocity compensation and SKT are jointly employed to correct the RM. After the RM correction, the azimuth echoes of a range cell where a target is located can be modeled as a cubic phase signal (CPS), whose chirp rate (CR) and quadratic CR are related to the target's radial acceleration and jerk, respectively. Thereafter, an effective parameters' estimation algorithm for CPS, called MICPF, is proposed and applied to compensate the DFM. After that, coherent integration and target detection are accomplished via the fast Fourier transform and constant false alarm rate technique, successively. Compared with the improved axis rotation discrete chirp Fourier transform, the SKT-MICPF achieves close detection performance, but greatly reduces the computational complexity. The results of simulation and real radar data demonstrate the validity of the proposed algorithm.
Maruyama, K; Oda, K
1984-01-01
Simian virus 40 (SV40) DNA insertions from SV40-transformed mouse cell line W-2K-11 and its revertants M18, M31, and M42 were cloned. W-2K-11 cells contain 1.5 copies of the SV40 sequences in a partially tandem duplicated form. The endpoints of the viral sequences at the virus-host junctions are located very close to those reported by others, indicating that there are some preferred sites for integration and rearrangement in SV40 sequences. One flanking cellular sequence is a long stretch of adenine and thymine with repeated AAAT, and the other is a stretch of guanine and cytosine with repeated CCG. There are patchy homologies between the flanking cellular sequences and the corresponding parental SV40 sequences. The sequences around both junctions were retained in all the revertants, whereas most of the internal SV40 sequences coding for large T antigen were deleted. The coding sequences for small T antigen are intact, and small T antigen was expressed in all the revertants. The fragments cloned from M18 and M42 were identical and 3.9 kilobases of SV40 sequences were deleted. The parental SV40 sequences around the deletion site have sequences capable of forming a secondary structure which might reduce the effective distance between the two regions. The SV40 DNA retained in M31 is colinear with SV40 virion DNA, and a unit length of SV40 DNA was deleted within the SV40 sequences present in W-2K-11 cells. These results indicated that two types of deletion occurred during the reversion, one between homologous sequences and the other between nonhomologous sequences. Images PMID:6319747
NASA Astrophysics Data System (ADS)
Talaghat, Mohammad Reza; Jokar, Seyyed Mohammad
2017-06-01
This article offers a study on estimation of heat transfer parameters (coefficient and thermal diffusivity) using analytical solutions and experimental data for regular geometric shapes (such as infinite slab, infinite cylinder, and sphere). Analytical solutions have a broad use in experimentally determining these parameters. Here, the method of Finite Integral Transform (FIT) was used for solutions of governing differential equations. The temperature change at centerline location of regular shapes was recorded to determine both the thermal diffusivity and heat transfer coefficient. Aluminum and brass were used for testing. Experiments were performed for different conditions such as in a highly agitated water medium (T = 52 °C) and in air medium (T = 25 °C). Then, with the known slope of the temperature ratio vs. time curve and thickness of slab or radius of the cylindrical or spherical materials, thermal diffusivity value and heat transfer coefficient may be determined. According to the method presented in this study, the estimated of thermal diffusivity of aluminum and brass is 8.395 × 10-5 and 3.42 × 10-5 for a slab, 8.367 × 10-5 and 3.41 × 10-5 for a cylindrical rod and 8.385 × 10-5 and 3.40 × 10-5 m2/s for a spherical shape, respectively. The results showed there is close agreement between the values estimated here and those already published in the literature. The TAAD% is 0.42 and 0.39 for thermal diffusivity of aluminum and brass, respectively.
Stable and Critical Noncohesive Coulomb Wedges: Exact Elastic Solutions
NASA Astrophysics Data System (ADS)
Wang, K.; Hu, Y.
2004-12-01
The theory of critically tapered Coulomb wedge has been successfully applied to model active fold-and-thrust belts or submarine accretionary prisms. Brittle mountain building is episodic in nature, controlled by changes in basal friction, erosion and sedimentation, and hydrogeology. Sediment accretion may be modulated by great subduction earthquakes. Between deformation episodes and/or during transition between compressional and extensional tectonics, the Coulomb wedges are stable (i.e., supercritical), to which the critical taper theory does not apply. In this work, we provide an exact elastic solution for stable wedges based on Airy stress functions. The stress equilibrium equation and definition of basal friction and basal and internal pore fluid pressure ratios are exactly the same as those used for Dahlen's [1984] exact solution for critical noncohesive Coulomb wedges, but internal friction μ becomes irrelevant. Given elastic - perfectly Coulomb-plastic rheology, for stresses in a wedge on the verge of Coulomb failure there must co-exist a critical taper solution involving μ and a unique equivalent elastic solution not involving μ . Our elastic solution precisely reduces to Dahlen's critical taper solution for critical conditions. For stable conditions, normal stress perpendicular to the surface slope σ z and shear stress τ xz are identical with those in a critical taper, but the slope-parallel normal stress is different. The elastic solution is also generally applicable to purely elastic wedges and useful for modeling geodetic observations. A stable noncohesive Coulomb wedge differs from a general elastic wedge in that its upper and lower surfaces stay at zero curvature during loading. Dahlen, F.A. (1984), Noncohesive critical Coulomb wedges: An exact solution, JGR, 89, 10,125-10,133.
Surplus angle and sign-flipped Coulomb force in projectable Horava-Lifshitz gravity
Kim, Hang Bae; Kim, Yoonbai
2010-11-15
We obtain the static spherically symmetric vacuum solutions of Horava-Lifshitz gravity theory, imposing the detailed balance condition only in the UV limit. We find the solutions in two different coordinate systems, the Painleve-Gullstrand coordinates and the Poincare coordinates, to examine the consequences of imposing the projectability condition. The solutions in two coordinate systems are distinct due to the nonrelativistic nature of the Horava-Lifshitz gravity. In the Painleve-Gullstrand coordinates compiling with the projectability condition, the solution involves an additional integration constant which yields surplus angle and implies attractive Coulomb force between same charges.
The Funk transform as a Penrose transform
NASA Astrophysics Data System (ADS)
Bailey, Toby N.; Eastwood, Michael G.; Gover, A. Rod; Mason, Lionel J.
1999-01-01
The Funk transform is the integral transform from the space of smooth even functions on the unit sphere S2[subset or is implied by][open face R]3 to itself defined by integration over great circles. One can regard this transform as a limit in a certain sense of the Penrose transform from [open face C][open face P]2 to [open face C][open face P]*ast;2. We exploit this viewpoint by developing a new proof of the bijectivity of the Funk transform which proceeds by considering the cohomology of a certain involutive (or formally integrable) structure on an intermediate space. This is the simplest example of what we hope will prove to be a general method of obtaining results in real integral geometry by means of complex holomorphic methods derived from the Penrose transform.
Yarimizu, Tohru; Nonklang, Sanom; Nakamura, Junpei; Tokuda, Shuya; Nakagawa, Takaaki; Lorreungsil, Sasithorn; Sutthikhumpha, Surasit; Pukahuta, Charida; Kitagawa, Takao; Nakamura, Mikiko; Cha-Aim, Kamonchai; Limtong, Savitree; Hoshida, Hisashi; Akada, Rinji
2013-12-01
The isolation and application of auxotrophic mutants for gene manipulations, such as genetic transformation, mating selection and tetrad analysis, form the basis of yeast genetics. For the development of these genetic methods in the thermotolerant fermentative yeast Kluyveromyces marxianus, we isolated a series of auxotrophic mutants with defects in amino acid or nucleic acid metabolism. To identify the mutated genes, linear DNA fragments of nutrient biosynthetic pathway genes were amplified from Saccharomyces cerevisiae chromosomal DNA and used to directly transform the K. marxianus auxotrophic mutants by random integration into chromosomes through non-homologous end joining (NHEJ). The appearance of transformant colonies indicated that the specific S. cerevisiae gene complemented the K. marxianus mutant. Using this interspecific complementation approach with linear PCR-amplified DNA, we identified auxotrophic mutations of ADE2, ADE5,7, ADE6, HIS2, HIS3, HIS4, HIS5, HIS6, HIS7, LYS1, LYS2, LYS4, LYS9, LEU1, LEU2, MET2, MET6, MET17, TRP3, TRP4 and TRP5 without the labour-intensive requirement of plasmid construction. Mating, sporulation and tetrad analysis techniques for K. marxianus were also established. With the identified auxotrophic mutant strains and S. cerevisiae genes as selective markers, NHEJ-mediated integrative transformation with PCR-amplified DNA is an attractive system for facilitating genetic analyses in the yeast K. marxianus.
PFLOW: A 3-D Numerical Modeling Tool for Calculating Fluid-Pressure Diffusion from Coulomb Strain
NASA Astrophysics Data System (ADS)
Wolf, L. W.; Lee, M.; Meir, A.; Dyer, G.; Ma, K.; Chan, C.
2009-12-01
A new 3D time-dependent pore-pressure diffusion model PFLOW is developed to investigate the response of pore fluids to the crustal deformation generated by strong earthquakes in heterogeneous geologic media. Given crustal strain generated by changes in Coulomb stress, this MATLAB-based code uses Skempton's coefficient to calculate resulting changes fluid pressure. Pore-pressure diffusion can be tracked over time in a user-defined model space with user-prescribed Neumann or Dirchilet boundary conditions and with spatially variable values of permeability. PFLOW employs linear or quadratic finite elements for spatial discretization and first order or second order, explicit or implicit finite difference discretization in time. PFLOW is easily interfaced with output from deformation modeling programs such as Coulomb (Toda et al., 2007) or 3D-DEF (Gomberg and Ellis, 1994). The code is useful for investigating to first-order the evolution of pore pressure changes induced by changes in Coulomb stress and their possible relation to water-level changes in wells or changes in stream discharge. It can also be used for student research and classroom instruction. As an example application, we calculate the coseismic pore pressure changes and diffusion induced by volumetric strain associated with the 1999 Chi-Chi earthquake (Mw = 7.6) in Taiwan. The Chi-Chi earthquake provides an unique opportunity to investigate the spatial and time-dependent poroelastic response of near-field rocks and sediments because there exist extensive observational data of water-level changes and crustal deformation. The integrated model allows us to explore whether changes in Coulomb stress can adequately explain hydrologic anomalies observed in areas such as Taiwan’s western foothills and the Choshui River alluvial plain. To calculate coseismic strain, we use the carefully calibrated finite fault-rupture model of Ma et al. (2005) and the deformation modeling code Coulomb 3.1 (Toda et al., 2007
Coulomb matrix elements in multi-orbital Hubbard models
NASA Astrophysics Data System (ADS)
Bünemann, Jörg; Gebhard, Florian
2017-04-01
Coulomb matrix elements are needed in all studies in solid-state theory that are based on Hubbard-type multi-orbital models. Due to symmetries, the matrix elements are not independent. We determine a set of independent Coulomb parameters for a d-shell and an f-shell and all point groups with up to 16 elements (O h , O, T d , T h , D 6h , and D 4h ). Furthermore, we express all other matrix elements as a function of the independent Coulomb parameters. Apart from the solution of the general point-group problem we investigate in detail the spherical approximation and first-order corrections to the spherical approximation.
Coulomb explosion of the hot spot of micropinches
NASA Astrophysics Data System (ADS)
Oreshkin, V. I.; Oreshkin, E. V.
2017-01-01
It has been shown that the generation of hard X-ray radiation, electron beam, and high energy ions that have been detected in experiments on compressing pinches can be related to the Coulomb explosion of a micropinch hot spot, which is formed due to the outflow of the material. In the outflow process, the plasma temperature in the hot spot increases and conditions appear for the transition of electrons to the regime of continuous acceleration. The exit of runaway electrons from the hot spot region leads to the creation of a positive bulk charge, then to a Coulomb explosion. Conditions under which electrons pass to the continuous acceleration regime have been determined and estimates of the ion kinetic energy upon a Coulomb explosion have been obtained.
Efros-Shklovskii Coulomb gap in the absence of disorder
NASA Astrophysics Data System (ADS)
Rademaker, Louk; Mahmoudian, Samiyeh; Ralko, Arnaud; Fratini, Simone; Dobrosavljevic, Vladimir
2015-03-01
Certain models of frustrated electron systems have been shown to self-generate glassy behavior, in the absence of disorder. Possible candidate materials contain quarter-filled triangular lattices with long-range Coulomb interactions, as found in the θ-family of organic BEDT-TTF crystals. In disordered insulators with localized electronic states, the so-called Coulomb glass, the single particle excitation spectrum displays the well-known Efros-Shklovskii gap. The same excitation spectrum is investigated in a class of models that display self-generated electronic glassiness, showing pseudogap formation related to the Efros-Shklovskii Coulomb gap. Our study suggests universal characteristics of all electron glasses, regardless of disorder.
Gribov horizon and Gribov copies effect in lattice Coulomb gauge
NASA Astrophysics Data System (ADS)
Burgio, Giuseppe; Quandt, Markus; Reinhardt, Hugo; Vogt, Hannes
2017-01-01
Following a recent proposal by Cooper and Zwanziger, we investigate via S U (2 ) lattice simulations the effect on the Coulomb gauge propagators and on the Gribov-Zwanziger confinement mechanism of selecting the Gribov copy with the smallest nontrivial eigenvalue of the Faddeev-Popov operator, i.e., the one closest to the Gribov horizon. Although such choice of gauge drives the ghost propagator towards the prediction of continuum calculations, we find that it actually overshoots the goal. With increasing computer time, we observe that Gribov copies with arbitrarily small eigenvalues can be found. For such a method to work, one would therefore need further restrictions on the gauge condition to isolate the physically relevant copies, since, for example, the Coulomb potential VC defined through the Faddeev-Popov operator becomes otherwise physically meaningless. Interestingly, the Coulomb potential alternatively defined through temporal link correlators is only marginally affected by the smallness of the eigenvalues.
Coulomb branch Hilbert series and Hall-Littlewood polynomials
NASA Astrophysics Data System (ADS)
Cremonesi, Stefano; Hanany, Amihay; Mekareeya, Noppadol; Zaffaroni, Alberto
2014-09-01
There has been a recent progress in understanding the chiral ring of 3d = 4 superconformal gauge theories by explicitly constructing an exact generating function (Hilbert series) counting BPS operators on the Coulomb branch. In this paper we introduce Coulomb branch Hilbert series in the presence of background magnetic charges for flavor symmetries, which are useful for computing the Hilbert series of more general theories through gluing techniques. We find a simple formula of the Hilbert series with background magnetic charges for T ρ ( G) theories in terms of Hall-Littlewood polynomials. Here G is a classical group and ρ is a certain partition related to the dual group of G. The Hilbert series for vanishing background magnetic charges show that Coulomb branches of T ρ ( G) theories are complete intersections. We also demonstrate that mirror symmetry maps background magnetic charges to baryonic charges.
Thermodynamic functions of the hcp Coulomb crystal lattice
NASA Astrophysics Data System (ADS)
Kozhberov, A. A.; Baiko, D. A.
2015-10-01
One-component Coulomb crystals of ions with hexagonal close-packed (hcp) lattice likely form in the crust of strongly-magnetized neutron stars (magnetars). In this work we present a detailed study of vibration modes and thermodynamic properties of such crystals in a wide range of temperatures at zero magnetic field. In contrast to typically considered lattices, the phonon spectrum of the system exhibits a peculiar crossing of the acoustic modes near the Brillouin zone center in certain directions of the wavevector. It is demonstrated that in the field-free regime the Helmholtz free energy of the hcp Coulomb crystal is always higher than those of the Coulomb crystals with body-centered cubic and face-centered cubic lattices. The results of our numerical calculations are fitted by simple analytic expressions.
NASA Astrophysics Data System (ADS)
Rys, Agnieszka; Falcon-Barroso, J.; van de Ven, G.
2013-01-01
Dwarf elliptical galaxies (dEs) are the most common galaxy class in dense environments. They are also a surprisingly inhomogenous class, which has made it challenging both to relate different dE subtypes to each other, as well as place the whole class in the larger context of galaxy assembly and (trans)formation processes. Here we will show the effects of environmental evolution on Virgo Cluster and field dEs, presenting the first large-scale integral-field spectroscopic (SAURON) data for this galaxy class. Our sample consists of 12 galaxies and no two of them are alike. We find that the level of rotation is not tied to flattening; we observe kinematic twists; we discover large-scale kinematically-decoupled components; we see varying gradients in line-strength maps. This great variety of morphological, kinematic, and stellar population parameters supports the claim that dEs are defunct dwarf spiral/irregular galaxies and points to a formation scenario that allows for a stochastic shaping of galaxy properties. The combined influence of ram-pressure stripping and harassment fulfils this requirement, still, their exact impact is not yet understood. We thus further investigate the properties of our sample by performing a detailed comprehensive analysis of its kinematic, dynamical, and stellar population properties. We infer the total (dark and baryonic) matter distribution by fitting the observed stellar velocity and velocity dispersion with the solutions of the Jeans equations. We obtain 2D age, metallicity, and enrichment information from line-strength analysis. We then tie these results to the galaxies' intrinsic (i.e. deprojected) locations in the cluster with the use of surface-brightness fluctuation distances. This step is essential to providing unbiased correlations with the local environment density. We show that the dark matter fraction, unlike the level of rotational support, appears to correlate with the clustrocentric distance, and that our dwarfs have
On rate-state and Coulomb failure models
Gomberg, J.; Beeler, N.; Blanpied, M.
2000-01-01
We examine the predictions of Coulomb failure stress and rate-state frictional models. We study the change in failure time (clock advance) Δt due to stress step perturbations (i.e., coseismic static stress increases) added to "background" stressing at a constant rate (i.e., tectonic loading) at time t0. The predictability of Δt implies a predictable change in seismicity rate r(t)/r0, testable using earthquake catalogs, where r0 is the constant rate resulting from tectonic stressing. Models of r(t)/r0, consistent with general properties of aftershock sequences, must predict an Omori law seismicity decay rate, a sequence duration that is less than a few percent of the mainshock cycle time and a return directly to the background rate. A Coulomb model requires that a fault remains locked during loading, that failure occur instantaneously, and that Δt is independent of t0. These characteristics imply an instantaneous infinite seismicity rate increase of zero duration. Numerical calculations of r(t)/r0 for different state evolution laws show that aftershocks occur on faults extremely close to failure at the mainshock origin time, that these faults must be "Coulomb-like," and that the slip evolution law can be precluded. Real aftershock population characteristics also may constrain rate-state constitutive parameters; a may be lower than laboratory values, the stiffness may be high, and/or normal stress may be lower than lithostatic. We also compare Coulomb and rate-state models theoretically. Rate-state model fault behavior becomes more Coulomb-like as constitutive parameter a decreases relative to parameter b. This is because the slip initially decelerates, representing an initial healing of fault contacts. The deceleration is more pronounced for smaller a, more closely simulating a locked fault. Even when the rate-state Δt has Coulomb characteristics, its magnitude may differ by some constant dependent on b. In this case, a rate-state model behaves like a modified
Running Coulomb potential and Lamb shift in QCD
Hoang, Andre H.; Manohar, Aneesh V.; Stewart, Iain W.
2001-07-01
The QCD {beta} function and the anomalous dimensions for the Coulomb potential and the static potential first differ at three loop order. We evaluate the three loop ultrasoft anomalous dimension for the Coulomb potential and give the complete three loop running. Using this result, we calculate the leading logarithmic Lamb shift for a heavy-quark{endash}antiquark bound state, which includes all contributions to the binding energies of the form m{alpha}{sub s}{sup 4}({alpha}{sub s}ln{alpha}{sub s}){sup k}, k{ge}0.
Separable wave equation for three Coulomb interacting particles
NASA Astrophysics Data System (ADS)
Colavecchia, F. D.; Gasaneo, G.; Garibotti, C. R.
1998-02-01
We consider a separable approximation to the Schrödinger equation for the three-body Coulomb problem and found its exact solution above the ionization threshold. This wave function accounts for different possible asymptotic behaviors and reduces to the well-known product of three two-body Coulomb waves (C3) for scattering conditions. The momenta and position-dependent modifications recently proposed for the Sommerfeld parameters, as an improvement to the C3 model, are analyzed. We show how these changes can be included in our model as a suitable physically based variations in the separable approximation for the wave equation.
Ratchet effect driven by Coulomb friction: the asymmetric Rayleigh piston.
Sarracino, A; Gnoli, A; Puglisi, A
2013-04-01
The effect of Coulomb friction is studied in the framework of collisional ratchets. It turns out that the average drift of these devices can be expressed as the combination of a term related to the lack of equipartition between the probe and the surrounding bath, and a term featuring the average frictional force. We illustrate this general result in the asymmetric Rayleigh piston, showing how Coulomb friction can induce a ratchet effect in a Brownian particle in contact with an equilibrium bath. An explicit analytical expression for the average velocity of the piston is obtained in the rare collision limit. Numerical simulations support the analytical findings.
Higher-order dynamical effects in Coulomb dissociation
Esbensen, H.; Bertsch, G.F.; Bertulani, C.A.
1995-08-01
Coulomb dissociation is a technique commonly used to extract the dipole response of nuclei far from stability. This technique is applicable if the dissociation is dominated by dipole transitions and if first-order perturbation theory is valid. In order to assess the significance of higher-order processes we solve numerically the time evolution of the wave function for a two-body breakup in the Coulomb field from a high Z target. We applied this method to the breakup reactions: {sup 11}Be {yields} {sup 10}Be + n and {sup 11}Li {yields} +2n. The latter is treated as a two-body breakup, using a di-neutron model.
Femtosecond studies of Coulomb explosion utilizing covariance mapping
NASA Astrophysics Data System (ADS)
Card, Dennis Alan
2000-10-01
The studies presented herein elucidate details of the Coulomb explosion event initiated through the interaction of molecular clusters with an intense femtosecond laser beam (>=1 PW/cm2). Clusters studied include ammonia, titanium-hydrocarbon, pyridine, and 7-azaindole. Covariance analysis is presented as a general technique to study the dynamical processes in clusters and to discern whether the fragmentation channels are competitive. Positive covariance determinations identify concerted processes such as the concomitant explosion of protonated cluster ions of asymmetrical size. Anti- covariance mapping is exploited to distinguish competitive reaction channels such as the production of highly charged nitrogen atoms formed at the expense of the protonated members of a cluster ion ensemble. This technique is exemplified in each cluster system studied. Kinetic energy analyses, from experiment and simulation, are presented to fully understand the Coulomb explosion event. A cutoff study strongly suggests that a Coulomb explosion create ions with two different energies, a direct result of an incomplete Coulomb explosion. A peak analysis implies a strong mass-to-charge dependence on the KER. Taken together, the two studies suggest a duality in the elastic and inelastic contributions to the energy released in a Coulomb explosion. Finally, backward-ejected ions were found capable of arriving before the ion expelled without energy from a Coulomb explosion. Gradient, clustering, and microchannel plate studies confirm the chaotic nature of the Coulomb explosion and the effect clusters have on the event. Backward-ejected protons are found to impact the repeller and eject adsorbed protons from the surface. Moreover, delayed fragmentation is suggested by proton time-of-flights. A cluster study demonstrates the need for clusters at low intensities. Conceptually, the dynamic charge resonance enhanced ionization (CREI) model explains these results of heterocyclic Coulomb explosion
Plasmons in Dimensionally Mismatched Coulomb Coupled Graphene Systems
NASA Astrophysics Data System (ADS)
Badalyan, S. M.; Shylau, A. A.; Jauho, A. P.
2017-09-01
We calculate the plasmon dispersion relation for Coulomb coupled metallic armchair graphene nanoribbons and doped monolayer graphene. The crossing of the plasmon curves, which occurs for uncoupled 1D and 2D systems, is split by the interlayer Coulomb coupling into a lower and an upper plasmon branch. The upper branch exhibits an unusual behavior with end points at finite q . Accordingly, the structure factor shows either a single or a double peak behavior, depending on the plasmon wavelength. The new plasmon structure is relevant to recent experiments, its properties can be controlled by varying the system parameters and be used in plasmonic applications.
Effect of Coulombic friction on spatial displacement statistics.
Menzel, Andreas M; Goldenfeld, Nigel
2011-07-01
The phenomenon of Coulombic friction enters the stochastic description of dry friction between two solids and the statistic characterization of vibrating granular media. Here we analyze the corresponding Fokker-Planck equation including both velocity and spatial components, exhibiting a formal connection to a quantum mechanical harmonic oscillator in the presence of a delta potential. Numerical solutions for the resulting spatial displacement statistics show a crossover from exponential to Gaussian displacement statistics. We identify a transient intermediate regime that exhibits multiscaling properties arising from the contribution of Coulombic friction. The possible role of these effects during observations in diffusion experiments is briefly discussed.
Modified Coulomb-Dipole Theory for 2e Photoionization
NASA Technical Reports Server (NTRS)
2004-01-01
In the light of recent experiment on 2e photoionization of Li near threshold, we have considered a modification of the Coulomb-dipole theory, retaining the basic assumption that the threshold is dominated by asymmetric events in phase space [implies r(sub 1), k(sub 1)) greater than or equal to 2(r(sub 2), k(sub )]. In this region [in a collinear model, 2/r(sub 12) approached + 2/(r(sub 1)+r(sub 2)] the interaction reduces to V(rIsub 1) is greater than or equal to 2r(sub 2) is identically equal to [(-Z/r(sub 2)-(A-1)/r(sub 1)] + [(-2r(sub 2)/r(sub 1 exp 2)] is identically equal to V(sub c)+[V(sub d)]. For two electron emission Z = 2, thus both electrons see a Coulomb potential (V(sub c)) asymptotically, albeit each seeing a different charge. The residual potential (V(sub d)) is dipole in character. Writing the total psi = psi (sub c) + psi(sub d) = delta psi, and noting that. (T+V(sub c)-E)psy(sub c) = 0 and (T+V(sub c))psi(sub d) = 0 can be solved exactly, we find, substituting psi into the complete Schrod. Eq., that delta psi = -(H-E)(exp -1)(V(sub d) psi(sub 0)+V(sub c psi (sub 1). Using the fact that the absolute value of V(sub c) is much more than the absolute value of V(sub d) in almost all of configuration space, we can replace H by H(sub 0) in 9H-E)(exp -1) to obtain an improved approximation psi (improved) = psi(sub c) + psi(sub d) -(H(sub 0)-E)(exp -1) (V(sub c) psi (sub 0) + V(sub c) psi(sub 1). Here's the Green's function (H(sub 0)-E)(exp -1), can be exhibited explicitly, but the last term in psi (improved) is small, compared to the first two terms. Inserting them into the transition matrix element, which one handles in the usual way, we obtain in the limit E approaches 0, the threshold law: Q(E) alpha E + M(E)E(exp 5/4) + higher order (Eq. 1a). The modulation function, M(E), is a well-defined (but very non-trivial integral, but it is expected to be well approximated by a sinusoidal function containing a dipole phase term (M(E) = c sin[alpha log (E
NASA Astrophysics Data System (ADS)
Shi, Ying; Nimmo, Jonathan; Zhao, Junxiao
2017-05-01
The paper presents two results. First it is shown how the discrete potential modified KdV equation and its Lax pairs in matrix form arise from the Hirota-Miwa equation by a 2-periodic reduction. Then Darboux transformations and binary Darboux transformations are derived for the discrete potential modified KdV equation and it is shown how these may be used to construct exact solutions.
Symbolic programming language in molecular multicenter integral problem
NASA Astrophysics Data System (ADS)
Safouhi, Hassan; Bouferguene, Ahmed
It is well known that in any ab initio molecular orbital (MO) calculation, the major task involves the computation of molecular integrals, among which the computation of three-center nuclear attraction and Coulomb integrals is the most frequently encountered. As the molecular system becomes larger, computation of these integrals becomes one of the most laborious and time-consuming steps in molecular systems calculation. Improvement of the computational methods of molecular integrals would be indispensable to further development in computational studies of large molecular systems. To develop fast and accurate algorithms for the numerical evaluation of these integrals over B functions, we used nonlinear transformations for improving convergence of highly oscillatory integrals. These methods form the basis of new methods for solving various problems that were unsolvable otherwise and have many applications as well. To apply these nonlinear transformations, the integrands should satisfy linear differential equations with coefficients having asymptotic power series in the sense of Poincaré, which in their turn should satisfy some limit conditions. These differential equations are very difficult to obtain explicitly. In the case of molecular integrals, we used a symbolic programming language (MAPLE) to demonstrate that all the conditions required to apply these nonlinear transformation methods are satisfied. Differential equations are obtained explicitly, allowing us to demonstrate that the limit conditions are also satisfied.
Kit, S; Hazen, M; Otsuka, H; Qavi, H; Trkula, D; Dubbs, D R
1981-12-01
To analyze the site of integration of the herpes simplex virus type I (HSV-I) thymidine kinase (TK) gene in biochemically transformed human cells, TK-HeLa-(BU25) cells were transformed to the TK+ phenotype by a cloned, 2 kbp Pvull fragment of HSV-I DNA. The transformed cells [HeLa(BU25)/TF pAGO PP3] were fused with mouse LM(TK-) cells, and human-mouse somatic cell hybrid clones (LH PP3 clones 1, 2, 3, 5 and 6) were isolated in HATG-ouabain selective medium. The HeLa(BU25)/TF pAGO PP3 cells and the LH PP3 hybrid clones expressed HSV-I specific TK activity and a herpesvirus-associated nuclear antigen, and contained herpesvirus nucleotide sequences. Molecular hybridization experiments were carried out to map the HSV-I and flanking cellular nucleotide sequences in the biochemically transformed cells. These experiments demonstrated that the HSV-I nucleotide sequences were integrated at a single site, and that the same cellular nucleotide sequences flanked the viral DNA in transformed HeLa(BU25)/TF pAGO PP3 and LH PP3 clone 5 cells. TK- revertant subclones isolated by growing the LH PP3 clone 5 cells in BrdUrd (and diphtheria toxin) failed to form colonies in HATG medium, but retained HSV-I nucleotide sequences. Isozyme analyses on 21 gene-enzyme systems representing 21 human chromosomes revealed that all of the LH PP3 clonal lines expressed human hexosaminidase B, which has been assigned to chromosome 5, and all were sensitive to diphtheria toxin, which is also a marker for chromosome 5. Chromosome analyses showed that chromosome 5 was the nly human chromosome present in mitoses of LH PP3 clone 5 cells and that human chromosome 5 was present in most of the mitoses of LH PP3 clone 1, 2, 3, and 6 cells. The latter clones also contained 1 or 2 additional human chromosomes in some of the cells. As expected from the molecular hybridization analyses, TK- revertants of LH PP3 clone 5 cells retained portions of chromosome 5 and expressed human hexosaminidase B. The results
Accurate Coulomb blockade thermometry up to 60 kelvin.
Meschke, M; Kemppinen, A; Pekola, J P
2016-03-28
We demonstrate experimentally a precise realization of Coulomb blockade thermometry working at temperatures up to 60 K. Advances in nano-fabrication methods using electron beam lithography allow us to fabricate uniform arrays of sufficiently small tunnel junctions to guarantee an overall temperature reading precision of about 1%.
Coulomb Interactions in Hanbury Brown-Twiss Experiments with Electrons
ERIC Educational Resources Information Center
Shen, Kan
2009-01-01
This dissertation examines the effect of Coulomb interactions in Hanbury Brown-Twiss (HBT) type experiments with electrons. HBT experiments deal with intensity interference, which is related to the second-order correlation function of the particle field. This is an extension of the usual amplitude interference experiment, such as Young's…
Coulomb gauge approach for charmonium meson and hybrid radiative transitions
Gou, Peng; Yepez-Martínez, Tochtli; Szczepaniak, Adam P.
2015-01-22
We consider the lowest order interaction of the Foldy-Wouthuysen QED and QCD Hamiltonian in the Coulomb gauge approach, to describe radiative transitions between conventional and hybrids charmonium mesons. The results are compared to potential quark models and lattices calculations.
Interpolating the Coulomb phase of little string theory
Lin, Ying -Hsuan; Shao, Shu -Heng; Wang, Yifan; Yin, Xi
2015-12-03
We study up to 8-derivative terms in the Coulomb branch effective action of (1,1) little string theory, by collecting results of 4-gluon scattering amplitudes from both perturbative 6D super-Yang-Mills theory up to 4-loop order, and tree-level double scaled little string theory (DSLST). In previous work we have matched the 6-derivative term from the 6D gauge theory to DSLST, indicating that this term is protected on the entire Coulomb branch. The 8-derivative term, on the other hand, is unprotected. In this paper we compute the 8-derivative term by interpolating from the two limits, near the origin and near the infinity on the Coulomb branch, numerically from SU(k) SYM and DSLST respectively, for k=2,3,4,5. We discuss the implication of this result on the UV completion of 6D SYM as well as the strong coupling completion of DSLST. As a result, we also comment on analogous interpolating functions in the Coulomb phase of circle-compactified (2,0) little string theory.
Existence of the thermodynamic limit for disordered quantum Coulomb systems
NASA Astrophysics Data System (ADS)
Blanc, Xavier; Lewin, Mathieu
2012-09-01
Following a recent method introduced by Hainzl, Solovej, and Lewin, we prove the existence of the thermodynamic limit for a system made of quantum electrons, and classical nuclei whose positions and charges are randomly perturbed in an ergodic fashion. All the particles interact through Coulomb forces.
Coulomb crystals of oil droplets in a Paul trap
NASA Astrophysics Data System (ADS)
Triplett, Matt; Younger, Richard; Robertson, Scott
1998-10-01
Coulomb crystals of charged liquid droplets have been created in a Paul trap in air. The technique improves upon similar experiments with solid dust by having particles with a controlled and reproducible charge-to-mass ratio. The spatial configurations of crystals of a few particles have been determined.
Limits to Electron Beam Emittance from Stochastic Coulomb Interactions
Coleman-Smith, Christopher; Padmore, Howard A.; Wan, Weishi
2008-08-22
Dense electron beams can now be generated on an ultrafast timescale using laser driven photo-cathodes and these are used for a range of applications from ultrafast electron defraction to free electron lasers. Here we determine a lower bound to the emittance of an electron beam limited by fundamental stochastic Coulomb interactions.
Finiteness of the Coulomb gauge QCD perturbative effective action
Andraši, A.; Taylor, J.C.
2015-05-15
At 2-loop order in the Coulomb gauge, individual Feynman graphs contributing to the effective action have energy divergences. It is proved that these cancel in suitable combinations of graphs. This has previously been shown only for transverse external fields. The calculation results in a generalization of the Christ–Lee term which was inserted into the Hamiltonian.
Interpolating the Coulomb phase of little string theory
Lin, Ying -Hsuan; Shao, Shu -Heng; Wang, Yifan; ...
2015-12-03
We study up to 8-derivative terms in the Coulomb branch effective action of (1,1) little string theory, by collecting results of 4-gluon scattering amplitudes from both perturbative 6D super-Yang-Mills theory up to 4-loop order, and tree-level double scaled little string theory (DSLST). In previous work we have matched the 6-derivative term from the 6D gauge theory to DSLST, indicating that this term is protected on the entire Coulomb branch. The 8-derivative term, on the other hand, is unprotected. In this paper we compute the 8-derivative term by interpolating from the two limits, near the origin and near the infinity onmore » the Coulomb branch, numerically from SU(k) SYM and DSLST respectively, for k=2,3,4,5. We discuss the implication of this result on the UV completion of 6D SYM as well as the strong coupling completion of DSLST. As a result, we also comment on analogous interpolating functions in the Coulomb phase of circle-compactified (2,0) little string theory.« less
Coulomb Interactions in Hanbury Brown-Twiss Experiments with Electrons
ERIC Educational Resources Information Center
Shen, Kan
2009-01-01
This dissertation examines the effect of Coulomb interactions in Hanbury Brown-Twiss (HBT) type experiments with electrons. HBT experiments deal with intensity interference, which is related to the second-order correlation function of the particle field. This is an extension of the usual amplitude interference experiment, such as Young's…
Coulomb repulsion and the electron beam directed energy weapon
NASA Astrophysics Data System (ADS)
Retsky, Michael W.
2004-09-01
Mutual repulsion of discrete charged particles or Coulomb repulsion is widely considered to be an ultimate hard limit in charged particle optics. It prevents the ability to finely focus high current beams into small spots at large distances from defining apertures. A classic example is the 1970s era "Star Wars" study of an electron beam directed energy weapon as an orbiting antiballistic missile device. After much analysis, it was considered physically impossible to focus a 1000-amp 1-GeV beam into a 1-cm diameter spot 1000-km from the beam generator. The main reason was that a 1-cm diameter beam would spread to 5-m diameter at 1000-km due to Coulomb repulsion. Since this could not be overcome, the idea was abandoned. But is this true? What if the rays were reversed? That is, start with a 5-m beam converging slightly with the same nonuniform angular and energy distribution as the electrons from the original problem were spreading at 1000-km distance. Could Coulomb repulsion be overcome? Looking at the terms in computational studies, some are reversible while others are not. Based on estimates, the nonreversible terms should be small - of the order of 0.1 mm. If this is true, it is possible to design a practical electron beam directed weapon not limited by Coulomb repulsion.
Exchange Coulomb interaction in nanotubes: Dispersion of Langmuir waves
Andreev, P. A. Ivanov, A. Yu.
2015-07-15
The microscopic derivation of the Coulomb exchange interaction for electrons located on the nanotubes is presented. The derivation is based on the many-particle quantum hydrodynamic method. We demonstrate the effect of curvature of the nanocylinders on the force of exchange interaction. We calculate corresponding dispersion dependencies for electron oscillations on the nanotubes.
Isotope shifts and coulomb displacement energies in calcium isotopes
NASA Astrophysics Data System (ADS)
Caurier, E.; Poves, A.; Zuker, A.
1980-10-01
Isotope shifts, neutron-proton radii differences and Coulomb displacement energies are calculated for calcium isotopes A = 41 to 48. A simple parametrization of the core polarization terms of the effective force in the framework of the Isospin Projected Hartree-Fock (IPHF) method leads to good agreement between theory and experiment.
Hamiltonian flow in Coulomb gauge Yang-Mills theory
Leder, Markus; Reinhardt, Hugo; Pawlowski, Jan M.; Weber, Axel
2011-01-15
We derive a new functional renormalization group equation for Hamiltonian Yang-Mills theory in Coulomb gauge. The flow equations for the static gluon and ghost propagators are solved under the assumption of ghost dominance within different diagrammatic approximations. The results are compared to those obtained in the variational approach and the reliability of the approximations is discussed.
Borisenko conducts Kulonovskiy Kristall (Coulomb Crystal) Experiment in MRM2
2011-04-18
ISS027-E-013408 (18 April 2011) --- Russian cosmonaut Andrey Borisenko, Expedition 27 flight engineer, conducts an active session for the Russian experiment KPT-10 "Kulonovskiy Kristall" (Coulomb Crystal) in the Poisk Mini-Research Module 2 (MRM2) of the International Space Station.
Borisenko conducts Kulonovskiy Kristall (Coulomb Crystal) Experiment in MRM2
2011-04-18
ISS027-E-013406 (18 April 2011) --- Russian cosmonaut Andrey Borisenko, Expedition 27 flight engineer, conducts an active session for the Russian experiment KPT-10 "Kulonovskiy Kristall" (Coulomb Crystal) in the Poisk Mini-Research Module 2 (MRM2) of the International Space Station.
Application of Designer Polynomials to the Soft-Coulomb Potential
NASA Astrophysics Data System (ADS)
Weatherford, Charles; Wynn, Albert, III; Red, Eddie; Mathis, Clausell
2004-05-01
In a recent article [C.A. Weatherford, E. Red, A. Wynn III, International Journal of Quantum Chemistry 90, 1289-1294 (2002)], an algorithm was described whereby a synthetic weighted polynomial basis may be constructed which is adapted (designed) to a particular potential. It was applied therein to the Schroedinger equation with a coulomb potential in one dimension (-1/|x| ). A weighted polynomial basis with weight function w(x)=exp(-a|x|) was employed. It was observed that this potential had no even parity solutions - only odd parity solutions. The question arises as to the relationship of the solutions (eigenfunctions and eigenvalues) for this hard coulomb potential to the solutions for the soft coulomb potential (-1/ √x^2+b^2^1/2 ). In particular, since the soft coulomb potential is clearly expected to possess both even and odd parity solutions, how do these solutions behave as b->0 and thus what happens to the even solutions. This problem is deceptively difficult none of the standard basis sets produce a variational minimum as a function of 'a' for nonzero 'b'. This is apparently why this problem has never been done before. A new orthonormal basis was designed with weight function w(x)=exp(-a√x^2+b^2) which did produce a variational minimum for variable a and arbitrary fixed 'b'. The present paper describes these solutions and clearly indicates how they behave as b->0 .
Luo, H; Hu, Q; Nelson, K; Longo, C; Kausch, A P; Chandlee, J M; Wipff, J K; Fricker, C R
2004-04-01
Genetic transformation of creeping bentgrass mediated by Agrobacterium tumefaciens has been achieved. Embryogenic callus initiated from seeds (cv. Penn-A-4) was infected with an A. tumefaciens strain (LBA4404) harboring a super-binary vector that contained an herbicide-resistant bar gene driven either by the CaMV 35S promoter or a rice ubiquitin promoter. Plants were regenerated from 219 independent transformation events. The overall stable transformation efficiency ranged from 18% to 45%. Southern blot and genetic analysis confirmed transgene integration in the creeping bentgrass genome and normal transmission and stable expression of the transgene in the T1 generation. All independent transformation events carried one to three copies of the transgene, and a majority (60-65%) contained only a single copy of the foreign gene with no apparent rearrangements. We report here the successful use of Agrobacterium for the large-scale production of transgenic creeping bentgrass plants with a high frequency of a single-copy transgene insertion that exhibit stable inheritance patterns.
Ibrahim, Ahmed; Bucur, Anca; Perez-Rey, David; Alonso, Enrique; de Hoog, Matthy; Dekker, Andre; Marshall, M Scott
2015-01-01
This paper describes the data transformation pipeline defined to support the integration of a new clinical site in a standards-based semantic interoperability environment. The available datasets combined structured and free-text patient data in Dutch, collected in the context of radiation therapy in several cancer types. Our approach aims at both efficiency and data quality. We combine custom-developed scripts, standard tools and manual validation by clinical and knowledge experts. We identified key challenges emerging from the several sources of heterogeneity in our case study (systems, language, data structure, clinical domain) and implemented solutions that we will further generalize for the integration of new sites. We conclude that the required effort for data transformation is manageable which supports the feasibility of our semantic interoperability solution. The achieved semantic interoperability will be leveraged for the deployment and evaluation at the clinical site of applications enabling secondary use of care data for research. This work has been funded by the European Commission through the INTEGRATE (FP7-ICT-2009-6-270253) and EURECA (FP7-ICT-2011-288048) projects.
Ibrahim, Ahmed; Bucur, Anca; Perez-Rey, David; Alonso, Enrique; de Hoog, Matthy; Dekker, Andre; Marshall, M. Scott
2015-01-01
This paper describes the data transformation pipeline defined to support the integration of a new clinical site in a standards-based semantic interoperability environment. The available datasets combined structured and free-text patient data in Dutch, collected in the context of radiation therapy in several cancer types. Our approach aims at both efficiency and data quality. We combine custom-developed scripts, standard tools and manual validation by clinical and knowledge experts. We identified key challenges emerging from the several sources of heterogeneity in our case study (systems, language, data structure, clinical domain) and implemented solutions that we will further generalize for the integration of new sites. We conclude that the required effort for data transformation is manageable which supports the feasibility of our semantic interoperability solution. The achieved semantic interoperability will be leveraged for the deployment and evaluation at the clinical site of applications enabling secondary use of care data for research. This work has been funded by the European Commission through the INTEGRATE (FP7-ICT-2009-6-270253) and EURECA (FP7-ICT-2011-288048) projects. PMID:26306242
Hergenhahn, Uwe
2012-12-01
The paper gives an introduction into Interatomic and Intermolecular Coulombic Decay (ICD). ICD is an autoionization process, which contrary to Auger decay involves neighbouring sites of the initial vacancy as an integral part of the decay transition. As a result of ICD, slow electrons are produced which generally are known to be active in radiation damage. The author summarizes the properties of ICD and reviews a number of important experiments performed in recent years. Intermolecular Coulombic Decay can generally take place in weakly bonded aggregates in the presence of ionizing particles or ionizing radiation. Examples collected here mostly use soft X-rays produced by synchrotron radiation to ionize, and use rare-gas clusters, water clusters or solutes in a liquid jet to observe ICD after irradiation. Intermolecular Coulombic Decay is initiated by single ionization into an excited state. The subsequent relaxation proceeds via an ultra-fast energy transfer to a neighbouring site, where a second ionization occurs. Secondary electrons from ICD have clearly been identified in numerous systems. ICD can take place after primary ionization, as the second step of a decay cascade which also involves Auger decay, or after resonant excitation with an energy which exceeds the ionization potential of the system. ICD is expected to play a role whenever particles or radiation with photon energies above the ionization energies for inner valence electrons are present in weakly bonded matter, e.g., biological tissue. The process produces at the same time a slow electron and two charged atomic or molecular fragments, which will lead to structural changes around the ionized site.
ERIC Educational Resources Information Center
Goh, Tan Leng; Hannon, James C.; Newton, Maria; Webster, Collin; Podlog, Leslie; Pillow, Wanda
2013-01-01
A program titled Physical Education Programming Infusion (PEPI) was incorporated into a required science methods course for preservice classroom teachers (PCTs). Using the transformative learning theory and the social ecological model, the authors examined changes in PCTs' personal health behaviors and perceived barriers toward movement…
Unuofin, F O; Siswana, M; Cishe, E N
2016-01-01
Rock phosphate (RP) addition in cow-dung waste-paper mixtures at rates above 2% P has been reported to increase the rate of bio-transformation and humification of organic waste mixtures during vermicomposting to produce organic fertilizer for organic farming. However, the optimization of RP for vermicomposting was not established. The objective of this study was to determine the optimal amount of RP integration rates for effective bio-transformation of cow-dung waste-paper mixtures. Arrays of RP integration degrees (0, 0.5, 1, 1.5, 2, and 4% P as RP) were thoroughly mixed with cow- dung waste-paper mixtures to achieve an optimized C:N ratio of 30 and allowed to vermidegrade following the introduction of earthworms at a stocking mass of 12.5 g-worms kg(-1). The bio-transformation of the waste mixtures was examined by measuring C:N ratios and humification index (HI) and per cent ash and volatile solids. Application of 1% P as RP resulted in fast bio-transformation and maturation of cow-dung waste-paper mixtures. A scanning electron microscopy (SEM) was used to evaluate the morphological properties of the different vermicomposts affected by rates of RP showing the degree of degradation of initial compacted aggregates of cellulose and protein fibres in the mixtures at maturity. A germination test was used to further determine phytotoxicity of the final composts and microbial biomass assessment. The final vermicompost (organic fertilizer) had a C:N ratio of 7, MBC of 900 mg kg(-1) and HI of 27.1%. The RP incorporation rate of 1% P of RP investigated is therefore, recommended for efficient vermidegradation and humification of cow-dung waste-paper mixtures. However, higher rates of RP incorporation should be considered where greater P enrichment of the final vermicompost (organic fertilizer) is desired.
Compact Collision Kernels for Hard Sphere and Coulomb Cross Sections; Fokker-Planck Coefficients
Chang Yongbin; Shizgal, Bernie D.
2008-12-31
A compact collision kernel is derived for both hard sphere and Coulomb cross sections. The difference between hard sphere interaction and Coulomb interaction is characterized by a parameter {eta}. With this compact collision kernel, the calculation of Fokker-Planck coefficients can be done for both the Coulomb and hard sphere interactions. The results for arbitrary order Fokker-Planck coefficients are greatly simplified. An alternate form for the Coulomb logarithm is derived with concern to the temperature relaxation in a binary plasma.
NASA Astrophysics Data System (ADS)
Paul, J.; Stevens, C. E.; Zhang, H.; Dey, P.; McGinty, D.; McGill, S. A.; Smith, R. P.; Reno, J. L.; Turkowski, V.; Perakis, I. E.; Hilton, D. J.; Karaiskaj, D.
2017-06-01
We have performed two-dimensional Fourier transform spectroscopy on intrinsic and modulation doped quantum wells in external magnetic fields up to 10 T. In the undoped sample, the strong Coulomb interactions and the increasing separations of the electron and hole charge distributions with increasing magnetic fields lead to a nontrivial in-plane dispersion of the magneto-excitons. Thus, the discrete and degenerate Landau levels are coupled to a continuum. The signature of this continuum is the emergence of elongated spectral line shapes at the Landau level energies, which are exposed by the multidimensional nature of our technique. Surprisingly, the elongation of the peaks is completely absent in the lowest Landau level spectra obtained from the modulation doped quantum well at high fields.
Small-angle Coulomb collision model for particle-in-cell simulations
Lemons, Don S. Winske, Dan; Daughton, William; Albright, Brian
2009-03-20
We construct and investigate a set of stochastic differential equations that incorporate the physics of velocity-dependent small-angle Coulomb collisions among the plasma particles in a particle-in-cell simulation. Each particle is scattered stochastically from all the other particles in a simulation cell modeled as one or more Maxwellians. Total energy and momentum are conserved by linear transformation of the velocity increments. In two test simulations the proposed 'particle-moment' collision algorithm performs well with time steps as large as 10% of the relaxation time - far larger than a particle-pairing collision algorithm, in which pairs of particles are scattered from one another, requires to achieve the same accuracy.
Transformational Learners: Transformational Teachers
ERIC Educational Resources Information Center
Jones, Marguerite
2009-01-01
Transformational learning, according to Mezirow (1981), involves transforming taken-for-granted frames of reference into more discriminating, flexible "habits of mind". In teacher education, transformative learning impacts on the development of students' action theories, self-efficacy and professional attributes. Although considered…
The Transformations of Transformations.
ERIC Educational Resources Information Center
Lin, Francis Y.
2000-01-01
Harris's original idea of transformations has been changed several times in Chomsky's work. This article explicates these transformations, arguing that though their motivations are highly understandable, these transformations are not necessary for understanding the workings of natural languages. (Author/VWL)
NASA Astrophysics Data System (ADS)
Glaeske, H.-J.; Kilbas, Anatoly A.; Saigo, Megumi
2000-06-01
The paper is devoted to study the integral transformwith the kernelfor [beta]>0; Re([gamma])>1/[beta]-1; ; Re(z)>0, which is a generalization of the modified Bessel function of the third kind or Macdonald function K-[gamma](z). Properties of [lambda][gamma],[sigma]([beta])(z) are investigated and compositions of the operator L[gamma],[sigma]([beta]) with the left- and right-sided Liouville fractional integrals and derivatives are proved.
NASA Astrophysics Data System (ADS)
Santana, C. A.; Andrade, L. H. C.; Súarez, Y. R.; Yukimitu, K.; Moraes, J. C. S.; Lima, S. M.
2015-09-01
Fish scales have been used to differentiate fish species and to give information on water pollution, besides others different purposes. In the present work, we are proposing, for the first time to our knowledge, to available the absorption from fish scales with Fourier Transform Infrared Photoacoustic Spectroscopy (FTIR-PAS) to assess the environmental integrity of different habitats. The infrared absorption measurements were performed directly on fish scales from the Astyanax altiparanae species, in order to check if the scales, and consequently the species, can be used as environmental bioindicator. The main absorption intensities were used as variables in the multivariate statistical analysis. It was noted that the chemical composition of the scales is directly related to the available food in the habitats, which is related to the integrity level of the environmental. The results point the fish scales as bioindicator to be applied with FTIR-PAS for monitoring aquatic ecosystems.
NASA Astrophysics Data System (ADS)
Tiotsop, M.; Fotue, A. J.; Fotsin, H. B.; Fai, L. C.
2017-08-01
Bound polaron in RbCl delta quantum dot under electric field and Coulombic impurity were considered. The ground and first excited state energy were derived by employing Pekar variational and unitary transformation methods. Applying Fermi golden rule, the expression of temperature and polaron lifetime were derived. The decoherence was studied trough the Tsallis entropy. Results shows that decreasing (or increasing) the lifetime increases (or decreases) the temperature and delta parameter (electric field strength and hydrogenic impurity). This suggests that to accelerate quantum transition in nanostructure, temperature and delta have to be enhanced. The improvement of electric field and coulomb parameter, increases the lifetime of the delta quantum dot qubit. Energy spectrum of polaron increases with increase in temperature, electric field strength, Coulomb parameter, delta parameter, and polaronic radius. The control of the delta quantum dot energies can be done via the electric field, coulomb impurity, and delta parameter. Results also show that the non-extensive entropy is an oscillatory function of time. With the enhancement of delta parameter, non-extensive parameter, Coulombic parameter, and electric field strength, the entropy has a sinusoidal increase behavior with time. With the study of decoherence through the Tsallis entropy, it may be advised that to have a quantum system with efficient transmission of information, the non-extensive and delta parameters need to be significant. The study of the probability density showed an increase from the boundary to the center of the dot where it has its maximum value and oscillates with period T0 = ℏ / ΔE with the tunneling of the delta parameter, electric field strength, and Coulombic parameter. The results may be very helpful in the transmission of information in nanostructures and control of decoherence
The Effects of Static Coulomb Stress Change on Southern California Earthquake Forecasting
NASA Astrophysics Data System (ADS)
Strader, Anne Elizabeth
I investigate how inclusion of static Coulomb stress changes, caused by tectonic loading and previous seismicity, contributes to the effectiveness and reliability of prospective earthquake forecasts. Several studies have shown that positive static Coulomb stress changes are associated with increased seismicity, relative to stress shadows. However, it is difficult to avoid bias when the learning and testing intervals are chosen retrospectively. I hypothesize that earthquake forecasts based on static Coulomb stress fields may improve upon existing earthquake forecasts based on historical seismicity. Within southern California, I have confirmed the aforementioned relationship between earthquake location and Coulomb stress change, but found no identifiable triggering threshold based on static Coulomb stress history at individual earthquake locations. I have also converted static Coulomb stress changes into spatially-varying earthquake rates by optimizing an index function and calculating probabilities of cells containing at least one earthquake based on Coulomb stress ranges. Inclusion of Coulomb stress effects gives an improvement in earthquake forecasts that is significant with 95% confidence, compared to smoothed seismicity null forecasts. Because of large uncertainties in Coulomb stress calculations near faults (and aftershock distributions), I combine static Coulomb stress and smoothed seismicity into a hybrid earthquake forecast. Evaluating such forecasts against those in which only Coulomb stress or smoothed seismicity determines earthquake rates indicates that Coulomb stress is more effective in the far field, whereas statistical seismology outperforms Coulomb stress near faults. Additionally, I test effects of receiver plane orientation, stress type (normal and shear components), and declustering receiver earthquakes. While static Coulomb stress shows significant potential in a prospective earthquake forecast, simplifying assumptions compromise its
1980-05-01
equations. - , Part 2 of this paper deals with functions having support on (-oO) via a bilateral Laguerre transform which is an extension of the...the Laguerre Transform to Non- Integrable Functions Via Exponential Trans- formation 22 6. The Rate of Convergence of the Laguerre Coefficients 23 7...analy- tically via Laplace transformation , and full answers may be obtained when the Laplace transforms are invertible. More often than not, such
NASA Astrophysics Data System (ADS)
Li, Wei; Zhao, Jingkai; Zhang, Lei; Xia, Yinfeng; Liu, Nan; Li, Sujing; Zhang, Shihan
2016-01-01
A novel chemical absorption-biological reduction (CABR) integrated process, employing ferrous ethylenediaminetetraacetate (Fe(II)EDTA) as a solvent, is deemed as a potential option for NOx removal from the flue gas. Previous work showed that the Fe(II)EDTA concentration was critical for the NOx removal in the CABR process. In this work, the pathway of FeEDTA (Fe(III)/Fe(II)-EDTA) transformation was investigated to assess its impact on the NOx removal in a biofilter. Experimental results revealed that the FeEDTA transformation involved iron precipitation and EDTA degradation. X-ray photoelectron spectroscopy analysis confirmed the iron was precipitated in the form of Fe(OH)3. The iron mass balance analysis showed 44.2% of the added iron was precipitated. The EDTA degradation facilitated the iron precipitation. Besides chemical oxidation, EDTA biodegradation occurred in the biofilter. The addition of extra EDTA helped recover the iron from the precipitation. The transformation of FeEDTA did not retard the NO removal. In addition, EDTA rather than the iron concentration determined the NO removal efficiency.
Li, Wei; Zhao, Jingkai; Zhang, Lei; Xia, Yinfeng; Liu, Nan; Li, Sujing; Zhang, Shihan
2016-01-01
A novel chemical absorption-biological reduction (CABR) integrated process, employing ferrous ethylenediaminetetraacetate (Fe(II)EDTA) as a solvent, is deemed as a potential option for NOx removal from the flue gas. Previous work showed that the Fe(II)EDTA concentration was critical for the NOx removal in the CABR process. In this work, the pathway of FeEDTA (Fe(III)/Fe(II)-EDTA) transformation was investigated to assess its impact on the NOx removal in a biofilter. Experimental results revealed that the FeEDTA transformation involved iron precipitation and EDTA degradation. X-ray photoelectron spectroscopy analysis confirmed the iron was precipitated in the form of Fe(OH)3. The iron mass balance analysis showed 44.2% of the added iron was precipitated. The EDTA degradation facilitated the iron precipitation. Besides chemical oxidation, EDTA biodegradation occurred in the biofilter. The addition of extra EDTA helped recover the iron from the precipitation. The transformation of FeEDTA did not retard the NO removal. In addition, EDTA rather than the iron concentration determined the NO removal efficiency. PMID:26743930
Li, Wei; Zhao, Jingkai; Zhang, Lei; Xia, Yinfeng; Liu, Nan; Li, Sujing; Zhang, Shihan
2016-01-08
A novel chemical absorption-biological reduction (CABR) integrated process, employing ferrous ethylenediaminetetraacetate (Fe(II)EDTA) as a solvent, is deemed as a potential option for NOx removal from the flue gas. Previous work showed that the Fe(II)EDTA concentration was critical for the NOx removal in the CABR process. In this work, the pathway of FeEDTA (Fe(III)/Fe(II)-EDTA) transformation was investigated to assess its impact on the NOx removal in a biofilter. Experimental results revealed that the FeEDTA transformation involved iron precipitation and EDTA degradation. X-ray photoelectron spectroscopy analysis confirmed the iron was precipitated in the form of Fe(OH)3. The iron mass balance analysis showed 44.2% of the added iron was precipitated. The EDTA degradation facilitated the iron precipitation. Besides chemical oxidation, EDTA biodegradation occurred in the biofilter. The addition of extra EDTA helped recover the iron from the precipitation. The transformation of FeEDTA did not retard the NO removal. In addition, EDTA rather than the iron concentration determined the NO removal efficiency.
Narushima, Yuta; Kozuka-Hata, Hiroko; Koyama-Nasu, Ryo; Tsumoto, Kouhei; Inoue, Jun-ichiro; Akiyama, Tetsu; Oyama, Masaaki
2016-01-01
Glioblastoma is one of the most malignant brain tumors with poor prognosis and their development and progression are known to be driven by glioblastoma stem cells. Although glioblastoma stem cells lose their cancer stem cell properties during cultivation in serum-containing medium, little is known about the molecular mechanisms regulating signaling alteration in relation to reduction of stem cell-like characteristics. To elucidate the global phosphorylation-related signaling events, we performed a SILAC-based quantitative phosphoproteome analysis of serum-induced dynamics in glioblastoma stem cells established from the tumor tissues of the patient. Among a total of 2876 phosphorylation sites on 1584 proteins identified in our analysis, 732 phosphorylation sites on 419 proteins were regulated through the alteration of stem cell-like characteristics. The integrative computational analyses based on the quantified phosphoproteome data revealed the relevant changes of phosphorylation levels regarding the proteins associated with cytoskeleton reorganization such as Rho family GTPase and Intermediate filament signaling, in addition to transforming growth factor-β receptor type-2 (TGFBR2) as a prominent upstream regulator involved in the serum-induced phosphoproteome regulation. The functional association of transforming growth factor-β receptor type-2 with stem cell-like properties was experimentally validated through signaling perturbation using the corresponding inhibitors, which indicated that transforming growth factor-β receptor type-2 could play an important role as a novel cell fate determinant in glioblastoma stem cell regulation. PMID:26670566
Coulomb interaction driven instabilities of sliding Luttinger liquids
NASA Astrophysics Data System (ADS)
Sur, Shouvik; Yang, Kun
2017-08-01
We study systems made of periodic arrays of one-dimensional quantum wires coupled by Coulomb interaction. Using bosonization an interacting metallic fixed point is obtained, which is shown to be a higher-dimensional analog of the Tomonaga-Luttinger liquid, or a sliding Luttinger liquid. This non-Fermi liquid metallic state, however, is unstable in the presence of weak interwire backscatterings, which favor charge density wave states and suppress pairing. Depending on the effective strength of the Coulomb repulsion and the size of interwire spacing, various charge density wave states are stabilized, including Wigner crystal states. Our method allows for the determination of the specific ordering patterns and corresponding energy and temperature scales.
Stability of Dirac Liquids with Strong Coulomb Interaction
NASA Astrophysics Data System (ADS)
Tupitsyn, Igor S.; Prokof'ev, Nikolay V.
2017-01-01
We develop and apply the diagrammatic Monte Carlo technique to address the problem of the stability of the Dirac liquid state (in a graphene-type system) against the strong long-range part of the Coulomb interaction. So far, all attempts to deal with this problem in the field-theoretical framework were limited either to perturbative or random phase approximation and functional renormalization group treatments, with diametrically opposite conclusions. Our calculations aim at the approximation-free solution with controlled accuracy by computing vertex corrections from higher-order skeleton diagrams and establishing the renormalization group flow of the effective Coulomb coupling constant. We unambiguously show that with increasing the system size L (up to ln (L )˜40 ), the coupling constant always flows towards zero; i.e., the two-dimensional Dirac liquid is an asymptotically free T =0 state with divergent Fermi velocity.
Back to epicycles - relativistic Coulomb systems in velocity space
NASA Astrophysics Data System (ADS)
Ben-Ya'acov, Uri
2017-05-01
The study of relativistic Coulomb systems in velocity space is prompted by the fact that the study of Newtonian Kepler/Coulomb systems in velocity space, although less familiar than the analytic solutions in ordinary space, provides a much simpler (also more elegant) method. The simplicity and elegance of the velocity-space method derives from the linearity of the velocity equation, which is the unique feature of 1/r interactions for Newtonian and relativistic systems alike. The various types of possible trajectories are presented, their properties deduced from the orbits in velocity space, accompanied with illustrations. In particular, it is found that the orbits traversed in the relativistic velocity space (which is hyperbolic (H 3) rather than Euclidean) are epicyclic - circles whose centres also rotate - thus the title. Dedicated to the memory of J. D. Bekenstein - physicist, teacher and human
Coulomb effects in low-energy nuclear fragmentation
NASA Technical Reports Server (NTRS)
Wilson, John W.; Chun, Sang Y.; Badavi, Francis F.; John, Sarah
1993-01-01
Early versions of the Langley nuclear fragmentation code NUCFRAG (and a publicly released version called HZEFRG1) assumed straight-line trajectories throughout the interaction. As a consequence, NUCFRAG and HZEFRG1 give unrealistic cross sections for large mass removal from the projectile and target at low energies. A correction for the distortion of the trajectory by the nuclear Coulomb fields is used to derive fragmentation cross sections. A simple energy-loss term is applied to estimate the energy downshifts that greatly alter the Coulomb trajectory at low energy. The results, which are far more realistic than prior versions of the code, should provide the data base for future transport calculations. The systematic behavior of charge-removal cross sections compares favorably with results from low-energy experiments.
Conductance of a proximitized nanowire in the Coulomb blockade regime
NASA Astrophysics Data System (ADS)
van Heck, B.; Lutchyn, R. M.; Glazman, L. I.
2016-06-01
We identify the leading processes of electron transport across finite-length segments of proximitized nanowires and build a quantitative theory of their two-terminal conductance. In the presence of spin-orbit interaction, a nanowire can be tuned across the topological transition point by an applied magnetic field. Due to a finite segment length, electron transport is controlled by the Coulomb blockade. Upon increasing of the field, the shape and magnitude of the Coulomb blockade peaks in the linear conductance are defined, respectively, by Andreev reflection, single-electron tunneling, and resonant tunneling through the Majorana modes emerging after the topological transition. Our theory provides the framework for the analysis of experiments with proximitized nanowires [such as reported in S. M. Albrecht et al., Nature (London) 531, 206 (2016), 10.1038/nature17162] and identifies the signatures of the topological transition in the two-terminal conductance.
Structural phase transitions and topological defects in ion Coulomb crystals
Partner, Heather L.; Nigmatullin, Ramil; Burgermeister, Tobias; Keller, Jonas; Pyka, Karsten; Plenio, Martin B.; Retzker, Alex; Zurek, Wojciech Hubert; del Campo, Adolfo; Mehlstaubler, Tanja E.
2014-11-19
We use laser-cooled ion Coulomb crystals in the well-controlled environment of a harmonic radiofrequency ion trap to investigate phase transitions and defect formation. Topological defects in ion Coulomb crystals (kinks) have been recently proposed for studies of nonlinear physics with solitons and as carriers of quantum information. Defects form when a symmetry breaking phase transition is crossed non-adiabatically. For a second order phase transition, the Kibble-Zurek mechanism predicts that the formation of these defects follows a power law scaling in the rate of the transition. We demonstrate a scaling of defect density and describe kink dynamics and stability. We further discuss the implementation of mass defects and electric fields as first steps toward controlled kink preparation and manipulation.
Glassy Dynamics in Geometrically Frustrated Coulomb Liquids without Disorder
NASA Astrophysics Data System (ADS)
Mahmoudian, Samiyeh; Rademaker, Louk; Ralko, Arnaud; Fratini, Simone; Dobrosavljević, Vladimir
2015-07-01
We show that introducing long-range Coulomb interactions immediately lifts the massive ground state degeneracy induced by geometric frustration for electrons on quarter-filled triangular lattices in the classical limit. Important consequences include the stabilization of a stripe-ordered crystalline (global) ground state, but also the emergence of very many low-lying metastable states with amorphous "stripe-glass" spatial structures. Melting of the stripe order thus leads to a frustrated Coulomb liquid at intermediate temperatures, showing remarkably slow (viscous) dynamics, with very long relaxation times growing in Arrhenius fashion upon cooling, as typical of strong glass formers. On shorter time scales, the system falls out of equilibrium and displays the aging phenomena characteristic of supercooled liquids above the glass transition. Our results show remarkable similarity with the recent observations of charge-glass behavior in ultraclean triangular organic materials of the θ -(BEDT -TTF )2 family.
Glassy Dynamics in Geometrically Frustrated Coulomb Liquids without Disorder.
Mahmoudian, Samiyeh; Rademaker, Louk; Ralko, Arnaud; Fratini, Simone; Dobrosavljević, Vladimir
2015-07-10
We show that introducing long-range Coulomb interactions immediately lifts the massive ground state degeneracy induced by geometric frustration for electrons on quarter-filled triangular lattices in the classical limit. Important consequences include the stabilization of a stripe-ordered crystalline (global) ground state, but also the emergence of very many low-lying metastable states with amorphous "stripe-glass" spatial structures. Melting of the stripe order thus leads to a frustrated Coulomb liquid at intermediate temperatures, showing remarkably slow (viscous) dynamics, with very long relaxation times growing in Arrhenius fashion upon cooling, as typical of strong glass formers. On shorter time scales, the system falls out of equilibrium and displays the aging phenomena characteristic of supercooled liquids above the glass transition. Our results show remarkable similarity with the recent observations of charge-glass behavior in ultraclean triangular organic materials of the θ-(BEDT-TTF)(2) family.
Orbital ice: An exact Coulomb phase on the diamond lattice
Chern Giawei; Wu Congjun
2011-12-15
We demonstrate the existence of an orbital Coulomb phase as the exact ground state of a p-orbital exchange Hamiltonian on the diamond lattice. The Coulomb phase is an emergent state characterized by algebraic dipolar correlations and a gauge structure resulting from local constraints (ice rules) of the underlying lattice models. For most ice models on the pyrochlore lattice, these local constraints are a direct consequence of minimizing the energy of each individual tetrahedron. On the contrary, the orbital ice rules are emergent phenomena resulting from the quantum orbital dynamics. We show that the orbital ice model exhibits an emergent geometrical frustration by mapping the degenerate quantum orbital ground states to the spin-ice states obeying the 2-in-2-out constraints on the pyrochlore lattice. We also discuss possible realization of the orbital ice model in optical lattices with p-band fermionic cold atoms.
Low-energy Coulomb excitation of Sr,9896 beams
NASA Astrophysics Data System (ADS)
Clément, E.; Zielińska, M.; Péru, S.; Goutte, H.; Hilaire, S.; Görgen, A.; Korten, W.; Doherty, D. T.; Bastin, B.; Bauer, C.; Blazhev, A.; Bree, N.; Bruyneel, B.; Butler, P. A.; Butterworth, J.; Cederkäll, J.; Delahaye, P.; Dijon, A.; Ekström, A.; Fitzpatrick, C.; Fransen, C.; Georgiev, G.; Gernhäuser, R.; Hess, H.; Iwanicki, J.; Jenkins, D. G.; Larsen, A. C.; Ljungvall, J.; Lutter, R.; Marley, P.; Moschner, K.; Napiorkowski, P. J.; Pakarinen, J.; Petts, A.; Reiter, P.; Renstrøm, T.; Seidlitz, M.; Siebeck, B.; Siem, S.; Sotty, C.; Srebrny, J.; Stefanescu, I.; Tveten, G. M.; Van de Walle, J.; Vermeulen, M.; Voulot, D.; Warr, N.; Wenander, F.; Wiens, A.; De Witte, H.; Wrzosek-Lipska, K.
2016-11-01
The structure of neutron-rich Sr,9896 nuclei was investigated by low-energy safe Coulomb excitation of radioactive beams at the REX-ISOLDE facility, CERN, with the MINIBALL spectrometer. A rich set of transitional and diagonal E 2 matrix elements, including those for non-yrast structures, has been extracted from the differential Coulomb-excitation cross sections. The results support the scenario of a shape transition at N =60 , giving rise to the coexistence of a highly deformed prolate and a spherical configuration in 98Sr, and are compared to predictions from several theoretical calculations. The experimental data suggest a significant contribution of the triaxal degree of freedom in the ground state of both isotopes. In addition, experimental information on low-lying states in 98Rb has been obtained.
Coulomb excitation of C{sub 60} molecules
Esbensen, H.; Berry, H.G.; Cheng, S.
1995-08-01
The ionization and dissociation of C{sub 60} molecules in the Coulomb field from fast, highly-charged xenon ions was measured recently at ATLAS. The Coulomb excitation was modeled as a coherent excitation of the giant plasmon resonance. Guided by photo-absorption measurements, single-plasmon excitations were identified with the production of single-charged C{sub 60}{sup +} molecular ions. The calculated cross sections do indeed reproduce the beam energy-dependence of the measured C{sub 60}{sup +} yield. The calculations show that single-plasmon excitations are responsible for about half of the total reaction cross section. The other half, i.e., multiplasmon excitations, leads to multiple ionization and dissociation of the molecule.
Elastic scattering of Beryllium isotopes near the Coulomb barrier
Di Pietro, A.; Figuera, P.; Amorini, F.; Fisichella, M.; Lattuada, M.; Musumarra, A.; Pellegriti, M. G.; Randisi, G.; Rizzo, F.; Santonocito, D.; Scalia, G.; Scuderi, V.; Strano, E.; Torresi, D.; Papa, M.; Acosta, L.; Martel, I.; Perez-Bernal, F.; Borge, M. J. G.; Tengblad, O.
2011-10-28
In this contribution, results of experiments performed with the three Beryllium isotopes {sup 9,10,11}Be on a medium mass {sup 64}Zn target, at a center of mass energy of {approx_equal}1.4 the Coulomb barrier, will be discussed. Elastic scattering angular distributions have been measured for the {sup 9,10}Be reactions. In the {sup 11}Be case the quasielastic scattering angular distribution was obtained. In the halo nucleus case, the angular distribution exhibit a non-Fresnel-type pattern with a strong damping of the Coulomb-nuclear interference peak. Moreover, it is found that the total reaction cross-section for the halo nucleus induced collision is more than double the ones extracted in the collisions induced by the non-halo Beryllium isotopes. A large contribution to the total-reaction cross-section in the {sup 11}Be case could be attributed to transfer and/or break-up events.
Role of the Permanent Dipole Moment in Coulomb Explosion
NASA Astrophysics Data System (ADS)
Zhang, Cai-Ping; Miao, Xiang-Yang
2013-10-01
By numerically solving the non-Born—Oppenheimer time-dependent Schrödinger equation in a few-cycle chirped laser field (5-fs, 800-nm), the effect of the permanent dipole moment on the Coulomb explosion is studied by the kinetic-energy-release spectra with the “virtual detector" method. The results indicate that with the effect of the permanent dipole moment, different multiphoton processes for heteronuclear and homonuclear diatomic molecular ions may take place when the wave packets transit from the ground state (1sσg) to the first excited state (2pσu), and then move along the excited potential curve, and finally charge-resonant enhanced ionization occurs at critical internuclear distance. As a result, despite the similar ionization probabilities for these two systems at higher vibrational level with larger chirp parameter β, the structure of the Coulomb explosion spectrum for the former is prominently different from that for the latter.