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Sample records for sine-gordon model revisited

  1. Chiral sine-Gordon model

    NASA Astrophysics Data System (ADS)

    Yanagisawa, Takashi

    2016-02-01

    We investigate the chiral sine-Gordon model using the renormalization group method. The chiral sine-Gordon model is a model for G-valued fields and describes a new class of phase transitions, where G is a compact Lie group. We show that the model is renormalizable by means of a perturbation expansion and we derive beta functions of the renormalization group theory. The coefficients of beta functions are represented by the Casimir invariants. The model contains both asymptotically free and ultraviolet strong-coupling regions. The beta functions have a zero which is a bifurcation point that divides the parameter space into two regions; they are the weak-coupling region and the strong-coupling region. A large-N model is also considered. This model is reduced to the conventional sine-Gordon model that describes the Kosterlitz-Thouless transition near the fixed point. In the strong-coupling limit, the model is reduced to a U(N) matrix model.

  2. Classical lattice Sine-Gordon model

    SciTech Connect

    Tarasov, V.O.

    1987-05-20

    The completely integrable lattice regularization of the sine-Gordon model is studied by the inverse scattering method. The action-angle variables are shown to be the same for both the lattice and the continuous model. The lattice model solitons are constructed and their scattering is described.

  3. The Dynamical Sine-Gordon Model

    NASA Astrophysics Data System (ADS)

    Hairer, Martin; Shen, Hao

    2016-02-01

    We introduce the dynamical sine-Gordon equation in two space dimensions with parameter {β}, which is the natural dynamic associated to the usual quantum sine-Gordon model. It is shown that when {β2 in (0, 16π/3)} the Wick renormalised equation is well-posed. In the regime {β2 in (0, 4π)}, the Da Prato-Debussche method [J Funct Anal 196(1):180-210, 2002; Ann Probab 31(4):1900-1916, 2003] applies, while for {β2 in [4π, 16π/3)}, the solution theory is provided via the theory of regularity structures [Hairer, Invent Math 198(2):269-504, 2014]. We also show that this model arises naturally from a class of {2 + 1} -dimensional equilibrium interface fluctuation models with periodic nonlinearities. The main mathematical difficulty arises in the construction of the model for the associated regularity structure where the role of the noise is played by a non-Gaussian random distribution similar to the complex multiplicative Gaussian chaos recently analysed in Lacoin et al. [Commun Math Phys 337(2):569-632, 2015].

  4. Classical version of the lattice sine-Gordon model

    SciTech Connect

    Tarasov, V.O.

    1986-09-10

    A completely integrable regularized lattice sine-Gordon model is considered by the method of the inverse scattering problem. It is shown that the variables of action-angle type for the lattice and continuous models coincide. Solitons of the lattice model are constructed, and their scattering is described.

  5. A classical version of the lattice Sine-Gordon model

    SciTech Connect

    Tarasov, V.O.

    1986-09-10

    A completely integrable regularized lattice Sine-Gordon model is considered by the method of the inverse scattering problem. It is shown that the variables of action-angle type for the lattice and continuous models coincide. Solitons of the lattice model are constructed, and their scattering is described.

  6. Functional Renormalization Group Approach to the Sine-Gordon Model

    SciTech Connect

    Nagy, S.; Sailer, K.; Nandori, I.; Polonyi, J.

    2009-06-19

    The renormalization group flow is presented for the two-dimensional sine-Gordon model within the framework of the functional renormalization group method by including the wave-function renormalization constant. The Kosterlitz-Thouless-Berezinski type phase structure is recovered as the interpolating scaling law between two competing IR attractive area of the global renormalization group flow.

  7. Generalized universality in the massive sine-Gordon model

    SciTech Connect

    Nagy, S.; Sailer, K.; Nandori, I.; Polonyi, J.

    2008-01-15

    A nontrivial interplay of the UV and IR scaling laws, a generalization of the universality is demonstrated in the framework of the massive sine-Gordon model, as a result of a detailed study of the global behavior of the renormalization group flow and the phase structure.

  8. Zero temperature landscape of the random sine-Gordon model

    SciTech Connect

    Sanchez, A.; Bishop, A.R.; Cai, D.

    1997-04-01

    We present a preliminary summary of the zero temperature properties of the two-dimensional random sine-Gordon model of surface growth on disordered substrates. We found that the properties of this model can be accurately computed by using lattices of moderate size as the behavior of the model turns out to be independent of the size above certain length ({approx} 128 x 128 lattices). Subsequently, we show that the behavior of the height difference correlation function is of (log r){sup 2} type up to a certain correlation length ({xi} {approx} 20), which rules out predictions of log r behavior for all temperatures obtained by replica-variational techniques. Our results open the way to a better understanding of the complex landscape presented by this system, which has been the subject of very many (contradictory) analysis.

  9. Functional Integrals and Convergence of Partition Function in Sine-Gordon-Thirring Model

    NASA Astrophysics Data System (ADS)

    Yan, Jun; Li, Bao-Lin

    2013-11-01

    The effective action in 1D sine-Gordon-Thirring model with impurities coupling is derived by means of functional integral method. For strong coupling model, the convergence of partition function is proved when coupling constants and wave vector satisfy certain constraint conditions. The fermion condense density in stable phase structure is obtained from the extremum of two-order effective action. The results showed that the non-perturbation method of functional integrals can be applied to study strong coupling rang of fermion system.

  10. Form factors of the sausage model obtained with bootstrap fusion from sine-Gordon theory

    SciTech Connect

    Horvath, Z.; Takacs, G.

    1996-03-01

    We continue the investigation of massive integrable models by means of the bootstrap fusion procedure started in our previous work on the O(3) nonlinear {sigma} model. Using an analogy with the SU(2) Thirring model and the O(3) nonlinear {sigma} model we prove a similar relation between sine-Gordon theory and a one-parameter deformation of the O(3) {sigma} model, the sausage model. This allows us to write down a free field representation for the Zamolodchikov-Faddeev algebra of the sausage model and to construct an integral representation for the generating functions of form factors in this theory. We also clear up the origin of the singularities in the bootstrap construction and the reason for the problem with the kinematical poles. {copyright} {ital 1996 The American Physical Society.}

  11. Correlations in the sine-Gordon model with finite soliton density

    NASA Astrophysics Data System (ADS)

    Aristov, D. N.; Luther, A.

    2002-04-01

    We study the sine-Gordon (SG) model at finite densities of the topological charge and small SG interaction constant, related to the one-dimensional Hubbard model near half filling. Using the modified Wentzel-Kramers-Brillouin approach, we find that the spectrum of the Gaussian fluctuations around the classical solution reproduces the results of the Bethe ansatz studies. The modification of the collective coordinate method allows us to write down the action, free from infrared divergencies. The behavior of the density-type correlation functions is nontrivial and we demonstrate the existence of leading and subleading asymptotes. A consistent definition of the charge-raising operator is discussed. The superconducting-type correlations are shown to decrease slowly at small soliton densities, while the spectral weight of right (left) moving fermions is spread over neighboring ``4kF'' harmonics.

  12. Collective coordinates theory for discrete soliton ratchets in the sine-Gordon model.

    PubMed

    Snchez-Rey, Bernardo; Quintero, Niurka R; Cuevas-Maraver, Jess; Alejo, Miguel A

    2014-10-01

    A collective coordinate theory is developed for soliton ratchets in the damped discrete sine-Gordon model driven by a biharmonic force. An ansatz with two collective coordinates, namely the center and the width of the soliton, is assumed as an approximated solution of the discrete nonlinear equation. The dynamical equations of these two collective coordinates, obtained by means of the generalized travelling wave method, explain the mechanism underlying the soliton ratchet and capture qualitatively all the main features of this phenomenon. The numerical simulation of these equations accounts for the existence of a nonzero depinning threshold, the nonsinusoidal behavior of the average velocity as a function of the relative phase between the harmonics of the driver, the nonmonotonic dependence of the average velocity on the damping, and the existence of nontransporting regimes beyond the depinning threshold. In particular, it provides a good description of the intriguing and complex pattern of subspaces corresponding to different dynamical regimes in parameter space. PMID:25375582

  13. Collective coordinates theory for discrete soliton ratchets in the sine-Gordon model

    NASA Astrophysics Data System (ADS)

    Snchez-Rey, Bernardo; Quintero, Niurka R.; Cuevas-Maraver, Jess; Alejo, Miguel A.

    2014-10-01

    A collective coordinate theory is developed for soliton ratchets in the damped discrete sine-Gordon model driven by a biharmonic force. An ansatz with two collective coordinates, namely the center and the width of the soliton, is assumed as an approximated solution of the discrete nonlinear equation. The dynamical equations of these two collective coordinates, obtained by means of the generalized travelling wave method, explain the mechanism underlying the soliton ratchet and capture qualitatively all the main features of this phenomenon. The numerical simulation of these equations accounts for the existence of a nonzero depinning threshold, the nonsinusoidal behavior of the average velocity as a function of the relative phase between the harmonics of the driver, the nonmonotonic dependence of the average velocity on the damping, and the existence of nontransporting regimes beyond the depinning threshold. In particular, it provides a good description of the intriguing and complex pattern of subspaces corresponding to different dynamical regimes in parameter space.

  14. Quantum corrections to quasi-periodic solution of Sine-Gordon model and periodic solution of phi4 model

    NASA Astrophysics Data System (ADS)

    Kwiatkowski, G.; Leble, S.

    2014-03-01

    Analytical form of quantum corrections to quasi-periodic solution of Sine-Gordon model and periodic solution of phi4 model is obtained through zeta function regularisation with account of all rest variables of a d-dimensional theory. Qualitative dependence of quantum corrections on parameters of the classical systems is also evaluated for a much broader class of potentials u(x) = b2f(bx) + C with b and C as arbitrary real constants.

  15. Quantum corrections to static solutions of the sine-Gordon and Nahm models via a generalized zeta function

    NASA Astrophysics Data System (ADS)

    Leble, S.

    2009-07-01

    We consider one-dimensional Yang-Mills-Nahm and sine-Gordon models in terms of a class of nonlinear Klein-Gordon-Fock equations. We perform a semiclassical quantization of the models using a generalized zeta function and construct a representation of the quantum theory in terms of the diagonal of the Greens function for the heat equation with an elliptic potential via solutions of the Hermite equation. We formulate an alternative approach based on Baker-Akhiezer functions for the KP equation. We evaluate quantum corrections to the action of the Nahm and sine-Gordon models. We study the fields from the class of elliptic functions. We take extra variables of arbitrary dimensions into account for possible applications of quantized sine-Gordon solitons in solid state physics via the Frenkel-Kontorova model or other models. For the Nahm model, whose field is represented via an elliptic (lemniscate) integral by construction, the Yang-Mills field mass coincides with the correction evaluated as a hyperelliptic integral.

  16. The sine-Gordon model and the small. kappa. sup + region of light- cone perturbation theory

    SciTech Connect

    Griffin, P.A.

    1992-01-01

    The non-perturbative ultraviolet divergence of the sine-Gordon model is used to study the k{sup +} = 0 region of light-cone perturbation theory. The light-cone vacuum is shown to be unstable at the non- perturbative {beta}{sup 2} = 8{pi} critical point by a light-cone version of Coleman's variational method. Vacuum bubbles, which are k{sup +} = 0 diagram in light-cone field theory and are individually finite and non-vanishing for all {beta}, conspire to generate ultraviolet divergences of the light-cone energy density. The k{sup +} = 0 region of momentum also contributed to connected Green's functions: the connected two point function will not diverge, as it should, at the critical point unless diagrams which contribute only at k {sup +} = 0 are properly included. This analysis shows in a simple way how the k {sup +} = 0 region cannot be ignored even for connected diagrams. This phenomenon is expected to occur in higher dimensional gauge theories starting at two loop order in light-cone perturbation theory.

  17. Gravity localization in sine-Gordon braneworlds

    NASA Astrophysics Data System (ADS)

    Cruz, W. T.; Maluf, R. V.; Sousa, L. J. S.; Almeida, C. A. S.

    2016-01-01

    In this work we study two types of five-dimensional braneworld models given by sine-Gordon potentials. In both scenarios, the thick brane is generated by a real scalar field coupled to gravity. We focus our investigation on the localization of graviton field and the behaviour of the massive spectrum. In particular, we analyse the localization of massive modes by means of a relative probability method in a Quantum Mechanics context. Initially, considering a scalar field sine-Gordon potential, we find a localized state to the graviton at zero mode. However, when we consider a double sine-Gordon potential, the brane structure is changed allowing the existence of massive resonant states. The new results show how the existence of an internal structure can aid in the emergence of massive resonant modes on the brane.

  18. c-function and central charge of the sine-Gordon model from the non-perturbative renormalization group flow

    NASA Astrophysics Data System (ADS)

    Bacs, V.; Defenu, N.; Trombettoni, A.; Nndori, I.

    2015-12-01

    In this paper we study the c-function of the sine-Gordon model taking explicitly into account the periodicity of the interaction potential. The integration of the c-function along trajectories of the non-perturbative renormalization group flow gives access to the central charges of the model in the fixed points. The results at vanishing frequency ?2, where the periodicity does not play a role, are retrieved and the independence on the cutoff regulator for small frequencies is discussed. Our findings show that the central charge obtained integrating the trajectories starting from the repulsive low-frequencies fixed points (?2 < 8 ?) to the infra-red limit is in good quantitative agreement with the expected ?c = 1 result. The behavior of the c-function in the other parts of the flow diagram is also discussed. Finally, we point out that including also higher harmonics in the renormalization group treatment at the level of local potential approximation is not sufficient to give reasonable results, even if the periodicity is taken into account. Rather, incorporating the wave-function renormalization (i.e. going beyond local potential approximation) is crucial to get sensible results even when a single frequency is used.

  19. The sine-Gordon model and the small {kappa}{sup +} region of light- cone perturbation theory

    SciTech Connect

    Griffin, P.A.

    1992-09-01

    The non-perturbative ultraviolet divergence of the sine-Gordon model is used to study the k{sup +} = 0 region of light-cone perturbation theory. The light-cone vacuum is shown to be unstable at the non- perturbative {beta}{sup 2} = 8{pi} critical point by a light-cone version of Coleman`s variational method. Vacuum bubbles, which are k{sup +} = 0 diagram in light-cone field theory and are individually finite and non-vanishing for all {beta}, conspire to generate ultraviolet divergences of the light-cone energy density. The k{sup +} = 0 region of momentum also contributed to connected Green`s functions: the connected two point function will not diverge, as it should, at the critical point unless diagrams which contribute only at k {sup +} = 0 are properly included. This analysis shows in a simple way how the k {sup +} = 0 region cannot be ignored even for connected diagrams. This phenomenon is expected to occur in higher dimensional gauge theories starting at two loop order in light-cone perturbation theory.

  20. Dynamic damping in magnetic Sine-Gordon systems

    NASA Astrophysics Data System (ADS)

    Schbinger, M.; Jelitto, R. J.

    1981-09-01

    We study the influence of the elastic degrees of freedom of a one-dimensional spin-chain with ferromagnetic Heisenberg coupling in situations, where the magnetic dynamics can be described by a Sine-Gordon model. Compatibility of the Sine-Gordon approach with spin-lattice coupling is shown, and CsNiF3 and domain wall motion are discussed as concrete physical realizations. As a consequence of the spin-lattice interaction a soliton-phonon coupling arises, which destroys the formal Lorentz invariance of the Sine-Gordon system. The influence of this coupling on the soliton dynamics is investigated. It results in a dynamic damping of the soliton motion, which in general is not of viscous type. Moreover, the influences of the soliton-phonon coupling on the phonon dispersion are estimated and possible experimental consequences are discussed.

  1. Semiclassical quantization of the complex sine-Gordon field theory

    SciTech Connect

    de Vega, H.J.; Maillet, J.M.

    1983-09-15

    The complex sine-Gordon model, a classically integrable field theory which exhibits highly nontrivial renormalization properties, is quantized semiclassically. The classical multisoliton solutions are derived by the inverse scattering method. The semiclassical mass spectrum is obtained from these results by computing the small-fluctuation determinant around the one-soliton solution. Dimensional regularization is used here. The particle spectrum turns out to be constituted by bound states of fundamental particles of like charge. Finally, the semiclassical S matrix is calculated and crossing symmetry is exhibited.

  2. Quantum solitons and their classical relatives: Bethe Ansatz states in soliton sectors of the Sine--Gordon System

    SciTech Connect

    Garbaczewski, P.

    1982-04-01

    Previously we have found that the semiclassical sine--Gordon/Thirring spectrum can be received in the absence of quantum solitons via the spin 1/2 approximation of the quantized sine--Gordon system on a lattice. Later on, we have recovered the Hilbert space of quantum soliton states for the sine--Gordon system. In the present paper we present a derivation of the Bethe Ansatz eigenstates for the generalized ice model in this soliton Hilbert space. We demonstrate that via ''Wick rotation'' of a fundamental parameter of the ice model one arrives at the Bethe Ansatz eigenstates of the quantum sine--Gordon system. The latter is a ''local transition matrix'' ancestor of the coventional sine--Gordon/Thirring model, as derived by Faddeev et al. within the quantum inverse-scattering method. Our result is essentially based on the N

  3. Radial sine-Gordon kinks as sources of fast breathers.

    PubMed

    Caputo, J-G; Soerensen, M P

    2013-08-01

    We consider radial sine-Gordon kinks in two, three, and higher dimensions. A full two-dimensional simulation showing that azimuthal perturbations remain small allows us to reduce the problem to the one-dimensional radial sine-Gordon equation. We solve this equation on an interval [r(0),r(1)] and absorb all outgoing radiation. As the kink shrinks toward r(0), before the collision, its motion is well described by a simple law derived from the conservation of energy. In two dimensions for r(0)?2, the collision disintegrates the kink into a fast breather, while for r(0)?4 we obtain a kink-breather metastable state where breathers are shed at each kink "return." In three and higher dimensions d, an additional kink-oscillon state appears for small r(0). On the application side, the kink disintegration opens the way for new types of terahertz microwave generators. PMID:24032909

  4. Exact solutions to the sine-Gordon equation

    NASA Astrophysics Data System (ADS)

    Aktosun, Tuncay; Demontis, Francesco; van der Mee, Cornelis

    2010-12-01

    A systematic method is presented to provide various equivalent solution formulas for exact solutions to the sine-Gordon equation. Such solutions are analytic in the spatial variable x and the temporal variable t, and they are exponentially asymptotic to integer multiples of 2? as x ? ?. The solution formulas are expressed explicitly in terms of a real triplet of constant matrices. The method presented is generalizable to other integrable evolution equations where the inverse scattering transform is applied via the use of a Marchenko integral equation. By expressing the kernel of that Marchenko equation using a matrix exponential in terms of the matrix triplet and by exploiting the separability of that kernel, an exact solution formula to the Marchenko equation is derived, yielding various equivalent exact solution formulas for the sine-Gordon equation.

  5. Ultrashort light bullets described by the two-dimensional sine-Gordon equation

    SciTech Connect

    Leblond, Herve; Mihalache, Dumitru

    2010-06-15

    By using a reductive perturbation technique applied to a two-level model, this study puts forward a generic two-dimensional sine-Gordon evolution equation governing the propagation of femtosecond spatiotemporal optical solitons in Kerr media beyond the slowly varying envelope approximation. Direct numerical simulations show that, in contrast to the long-wave approximation, no collapse occurs, and that robust (2+1)-dimensional ultrashort light bullets may form from adequately chosen few-cycle input spatiotemporal wave forms. In contrast to the case of quadratic nonlinearity, the light bullets oscillate in both space and time and are therefore not steady-state lumps.

  6. Pulse evolution for a two-dimensional Sine-Gordon equation

    NASA Astrophysics Data System (ADS)

    Minzoni, A. A.; Smyth, Noel F.; Worthy, Annette L.

    2001-11-01

    The evolution lump and ring solutions of a Sine-Gordon equation in two-space dimensions is considered. Approximate equations governing this evolution are derived using a pulse or ring with variable parameters in an averaged Lagrangian for the Sine-Gordon equation. It was found by Neu [Physica D 43 (1990) 421] that angular variations of the pulse shape may stabilise it. However, no study of the radiation produced by the pulse was available. In the present work, the coupling of the pulse to the shed radiation is considered. It is shown both asymptotically and numerically that the angular dependence produces spiral waves which shed angular momentum, leading to the ultimate collapse of the pulse. Good quantitative agreement between the asymptotic and numerical solutions is found. In addition, it is shown how the results of the present work can be applied to the Baby Skyrme model. In this regard, it is shown how the non-zero degree of solutions of the Baby Skyrme model prevents the collapse of a non-zero degree pulse shedding zero degree radiation. It is also indicated how the present results could be applied to the study of vortex models. The analysis presented in this work shows how complicated behaviour due to radiation of angular momentum can be captured in simple terms by approximate equations for the relevant degrees of freedom.

  7. Solution of Sine-Gordon Equations with Weak and Moderate Inductive Couplings under Bias Current and Dissipations

    NASA Astrophysics Data System (ADS)

    Liu, Feng; Hu, Xiao

    2015-06-01

    It is found that coherent electromagnetic (EM) radiation in terahertz (THz) band takes place when a single crystal of cuprate high-Tc superconductor Bi2Sr2CaCu2O8+? (BSCCO) is biased by a dc voltage. In this work we study the inductively coupled sine-Gordon equations which compose a good model for intrinsic Josephson junctions (IJJs) realized in BSCCO due to the strong layer structure. We derive a general solution for the coupled sine-Gordon equations valid for weak and moderate inductive couplings, which can enhance injection of dc energy into IJJs and convert it to THz EM radiation. This solution evolves into the ? phase kink state known before for strong inductive coupling.

  8. Resurgence in sine-Gordon quantum mechanics: exact agreement between multi-instantons and uniform WKB

    NASA Astrophysics Data System (ADS)

    Misumi, Tatsuhiro; Nitta, Muneto; Sakai, Norisuke

    2015-09-01

    We compute multi-instanton amplitudes in the sine-Gordon quantum mechanics (periodic cosine potential) by integrating out quasi-moduli parameters corresponding to separations of instantons and anti-instantons. We propose an extension of Bogomolnyi-Zinn-Justin prescription for multi-instanton configurations and an appropriate subtraction scheme. We obtain the multi-instanton contributions to the energy eigenvalue of the lowest band at the zeroth order of the coupling constant. For the configurations with only instantons (anti-instantons), we obtain unambiguous results. For those with both instantons and anti-instantons, we obtain results with imaginary parts, which depend on the path of analytic continuation. We show that the imaginary parts of the multi-instanton amplitudes precisely cancel the imaginary parts of the Borel resummation of the perturbation series, and verify that our results completely agree with those based on the uniform-WKB calculations, thus confirming the resurgence structure: divergent perturbation series combined with the nonperturbative multi-instanton contributions conspire to give unambiguous results. We also study the neutral bion contributions in the {C}{P}^{N-1} model on {{R}}^1 {S}^1 with a small circumference, taking account of the relative phase moduli between the fractional instanton and anti-instanton. We find that the sign of the interaction potential depends on the relative phase moduli, and that both the real and imaginary parts resulting from quasi-moduli integral of the neutral bion get quantitative corrections compared to the sine-Gordon quantum mechanics.

  9. Energy conservative solutions to the system of full variational sine-Gordon equations in a unit sphere

    NASA Astrophysics Data System (ADS)

    Wang, Qin; Song, Kyungwoo

    2016-02-01

    We establish the global existence of a conservative weak solution to the Cauchy problem for a complete system of variational sine-Gordon equations, which models the motion of long waves on a neutral dipole chain in the continuum limit in a unit sphere. Although singularities may develop in finite time, the energy of the solution is conserved across singular times. We also obtain the continuous dependence of solutions on the given initial data.

  10. Noise induced breather generation in a sine-Gordon chain

    NASA Astrophysics Data System (ADS)

    Bodo, B.; Morfu, S.; Marqui, P.; Essimbi, B. Z.

    2009-01-01

    We consider a sine-Gordon chain driven sinusoidally at one end. In the absence of noise, there exists a well known critical value of the amplitude beyond which breather modes can be generated via the phenomenon of supratransmission. We consider values of the driving amplitude below the critical amplitude such that no breather propagates in the medium. We show that noise induces breather generation with a given probability depending on the noise intensity. We also propose a bifurcation diagram which extends the supratransmission effect to a more realistic signal, namely a noisy sinusoidal excitation. We finally discuss some promising signal processing applications that can be developed by taking into account the contribution of noise in the media sharing this supratransmission phenomenon.

  11. Twisted hierarchies associated with the generalized sine-Gordon equation

    NASA Astrophysics Data System (ADS)

    Ma, Hui; Wu, Derchyi

    2011-09-01

    Twisted U- and twisted U/K-hierarchies are soliton hierarchies introduced by Terng to find higher flows of the generalized sine-Gordon equation. Twisted O(J,J)/O(J) O(J)-hierarchies are among the most important classes of twisted hierarchies. In this paper, we derive explicit interesting first and higher flows of twisted O(J,J)/O(J) O(J)-hierarchies, justify that the one-dimensional systems of twisted O(J,J)/O(J) O(J)-hierarchies for J = Iq, n - q(1 ? q ? n - 1), called the generalized sinh-Gordon equations, are the Gauss-Codazzi equations for n-dimensional timelike submanifolds with constant sectional curvature 1 and index q in pseudo-Euclidean (2n - 1)-dimensional space {R}^{2n-1}_{2q-1} with index 2q - 1. Furthermore, a unified treatment of the inverse scattering theory for twisted O(J,J)/O(J) O(J)-hierarchies is provided.

  12. Creation of sine-Gordon solitons by a pulse force

    SciTech Connect

    Kivshar, Y.S. ); Malomed, B.A. ); Zhang Fei; Vazquez, L. )

    1991-01-01

    We study the problem of soliton generation by an external pulse force in the framework of the sine-Gordon system. The problem is applied to the creation of fluxons in long Josephson junctions or magnetic solitons in one-dimensional magnetic systems with an easy-plane anisotropy. In case of a small duration of driving pulse {ital T}, we find the connection between parameters of the pulse force and the wave field created after the pulse. To define the parameters of the generated soliton we use an approach based on the inverse scattering transform. The analytical results are presented in two cases when the spatial length {ital L} of the pulse is either much larger or much smaller than the value {ital V}{sub {ital g}T}, {ital V}{sub {ital g}} being the maximum value of the group velocity in the system. The threshold conditions admitting generation of either breathers or kink-antikink pairs are found. Numerical simulations are performed for arbitrary values of the ratio {ital L}/{ital V}{sub {ital g}T} but for small {ital T}. In two limiting cases the results are in good comparison with the obtained analytical formulas. The influence of dissipative losses on the soliton creation is also studied by analytical and numerical methods. It is demonstrated that dissipation leads to an increasing of the threshold conditions to generate solitons by the pulse force.

  13. What happens to linear properties as we move from the Klein-Gordon equation to the sine-Gordon equation

    SciTech Connect

    Kovalyov, Mikhail

    2010-06-15

    In this article the sets of solutions of the sine-Gordon equation and its linearization the Klein-Gordon equation are discussed and compared. It is shown that the set of solutions of the sine-Gordon equation possesses a richer structure which partly disappears during linearization. Just like the solutions of the Klein-Gordon equation satisfy the linear superposition principle, the solutions of the sine-Gordon equation satisfy a nonlinear superposition principle.

  14. {pi} kinks in the parametrically driven sine-Gordon equation and applications

    SciTech Connect

    Zharnitsky, V.; Mitkov, I.

    1997-07-08

    Parametrically driven sine-Gordon equation with a mean-zero forcing is considered. It is shown that the system is well approximated by the double sine-Gordon equation using the normal form technique. The reduced equation possesses {pi}-kink solutions, which are also observed numerically in the original system. This result is applied to domain walls dynamics in one-dimensional easy-plane ferromagnets. For such system the existence of {pi}-kinks implies the true domain structure in the presence of high-frequency magnetic field.

  15. From the sine-Gordon field theory to the Kardar-Parisi-Zhang growth equation

    NASA Astrophysics Data System (ADS)

    Calabrese, Pasquale; Kormos, Mrton; Le Doussal, Pierre

    2014-07-01

    We unveil a remarkable connection between the sine-Gordon quantum field theory and the Kardar-Parisi-Zhang (KPZ) growth equation. We find that the non-relativistic limit of the two-point correlation function of the sine-Gordon theory is related to the generating function of the height distribution of the KPZ field with droplet initial conditions, i.e. the directed polymer free energy with two endpoints fixed. As shown recently, the latter can be expressed as a Fredholm determinant which in the large-time separation limit converges to the GUE Tracy-Widom cumulative distribution. Possible applications and extensions are discussed.

  16. Symmetries and soliton solutions of the Galilean complex Sine-Gordon equation

    NASA Astrophysics Data System (ADS)

    de Melo, G. R.; de Montigny, M.; Pinfold, J.; Tuszynski, J. A.

    2016-03-01

    We discuss a new equation, the Galilean version of the complex Sine-Gordon equation in 1 + 1 dimensions, Ψxx (1 -Ψ* Ψ) + 2 imΨt +Ψ* Ψx2- Ψ(1 -Ψ* Ψ) 2 = 0, derived from its relativistic counterpart via Galilean covariance. We determine its Lie point symmetries, discuss some group-invariant solutions, and examine some soliton solutions. The reduction under Galilean symmetry leads to an equation similar to the stationary Gross-Pitaevskii equation. This work is motivated in part by recent applications of the relativistic complex Sine-Gordon equation to the dynamics of Q-balls.

  17. Renormalization group method for kink dynamics in a perturbed sine-Gordon equation

    NASA Astrophysics Data System (ADS)

    Wang, Li; Tu, Tao; Guo, Ping-Guo; Guo, Guang-Can

    2014-04-01

    In this paper, we show that renormalization group theory can be used to give a systematic description of the evolution of the kink in a perturbed sine-Gordon equation. The present method gives the same results as inverse scattering theory and other approaches, which may provide a new insight into the soliton dynamics of perturbed equations.

  18. Multifrequency and edge breathers in the discrete sine-Gordon system via subharmonic driving: Theory, computation and experiment

    NASA Astrophysics Data System (ADS)

    Palmero, F.; Han, J.; English, L. Q.; Alexander, T. J.; Kevrekidis, P. G.

    2016-01-01

    We consider a chain of torsionally-coupled, planar pendula shaken horizontally by an external sinusoidal driver. It has been known that in such a system, theoretically modeled by the discrete sine-Gordon equation, intrinsic localized modes, also known as discrete breathers, can exist. Recently, the existence of multifrequency breathers via subharmonic driving has been theoretically proposed and numerically illustrated by Xu et al. (2014) [21]. In this paper, we verify this prediction experimentally. Comparison of the experimental results to numerical simulations with realistic system parameters (including a Floquet stability analysis), and wherever possible to analytical results (e.g. for the subharmonic response of the single driven-damped pendulum), yields good agreement. Finally, we report the period-1 and multifrequency edge breathers which are localized at the open boundaries of the chain, for which we have again found good agreement between experiments and numerical computations.

  19. Length-scale competition in the damped sine-Gordon chain with spatiotemporal periodic driving

    NASA Astrophysics Data System (ADS)

    Cai, David; Bishop, A. R.; Snchez, Angel

    1993-08-01

    It is shown that there are two different regimes for the damped sine-Gordon chain driven by the spatiotemporal periodic force ? sin(?t-knx) with a flat initial condition. For ?>kn, the system first bifurcates at a critical ?c(n) to a translating two-breather excitation from a state locked to the driver. For ?sine-Gordon equation. A linear stability analysis reveals that, in addition to two competing length scales, namely, the width of the breathers and the spatial period of the driving, there is one more length scale which plays an important role in controlling the dynamics of the system at small driving. In the second regime the length scale kn controls the excitation. The above picture is further corroborated by numerical nonlinear spectral analysis. An energy-balance estimate is also presented and shown to predict the critical value of ? in good agreement with the numerical simulations.

  20. Double sine-Gordon ratchet induced by excitation of an internal mode.

    PubMed

    Willis, C R; Farzaneh, M

    2005-01-01

    In a recent paper [Phys. Rev. E 69, 056612 (2004)] we showed the symmetry analysis of Flach et al. [Phys. Rev. Lett. 88, 184101 (2002)] which predicted the appearance of directed energy current in homogeneously spatially extended systems described by nonlinear field equations coupled to a heat bath in the presence of a correct choice for the time dependence of an external ac field, E(t), was due to the excitation of an internal mode. Flach applied their analysis to the sine-Gordon (SG) equation and verified the symmetry breaking numerically. In the SG case we showed the internal mode coupled to the center of the mass variable, X(t), that caused the symmetry breaking was Gamma(t) the slope of the kink. We also found that the phonon dressing of the SG kink by the ac driver, chi(t), was necessary for the occurrence of a directed energy current in the SG equation. We show in the case of the double sine-Gordon (DSG) equation that the excitation of the internal mode, R(t) (where R(t) is the separation of the two subkinks that make up the DSG soliton), combined with the phonon dressing of the DSG soliton also causes a directed energy current. PMID:15697744

  1. Nonlinear quantum-mechanical system associated with Sine-Gordon equation in (1 + 2) dimensions

    SciTech Connect

    Zarmi, Yair

    2014-10-15

    Despite the fact that it is not integrable, the (1 + 2)-dimensional Sine-Gordon equation has N-soliton solutions, whose velocities are lower than the speed of light (c = 1), for all N ≥ 1. Based on these solutions, a quantum-mechanical system is constructed over a Fock space of particles. The coordinate of each particle is an angle around the unit circle. U, a nonlinear functional of the particle number-operators, which obeys the Sine-Gordon equation in (1 + 2) dimensions, is constructed. Its eigenvalues on N-particle states in the Fock space are the slower-than-light, N-soliton solutions of the equation. A projection operator (a nonlinear functional of U), which vanishes on the single-particle subspace, is a mass-density generator. Its eigenvalues on multi-particle states play the role of the mass density of structures that emulate free, spatially extended, relativistic particles. The simplicity of the quantum-mechanical system allows for the incorporation of perturbations with particle interactions, which have the capacity to “annihilate” and “create” solitons – an effect that does not have an analog in perturbed classical nonlinear evolution equations.

  2. Sine-Gordon modulation solutions: application to macroscopic friction, regular and slow earthquakes and fault dynamics

    NASA Astrophysics Data System (ADS)

    Gershenzon, Naum; Bambakidis, Gust

    2014-05-01

    The Frenkel-Kontorova (FK) model and its continuum approximation, the sine-Gordon (SG) equation, are widely used for modeling various phenomena. In many practical applications the wave-train solution, which includes many solitons, is required. In such cases the system of Whitham's modulation equations, superimposed on the SG equation, provides such a solution. Here we consider several applications which use the SG modulation solutions [1-3]. Fault dynamics in the earth's crust, i.e. the nucleation and development of regular and slow earthquakes, is a complicated multidisciplinary problem which has been investigated using diverse approaches. Our approach, inspired by dislocation dynamics in crystals, is based on the FK model introduced to describe plasticity. In the model we propose, sliding occurs due to the movement of defects of a certain type (i.e. areas on the frictional surface with locally stressed material, known as a macroscopic dislocation or slip pulse) nucleated by shear stress in the presence of asperities. The spatial translation of a dislocation requires only a small fraction of the stress necessary for the uniform relative displacement of frictional surfaces. This is a fundamental distinction between our approach to macroscopic dry friction and those of others such as the Burridge-Knopoff and rate-and-state types of models. We show how this model can be applied to the qualitative and quantitative description of fault dynamics in general, and slow and regular earthquakes in particular. The three fundamental speeds of plate movement, earthquake migration, and seismic waves are shown to be connected in the FK model. The velocity of nonelastic stress propagation along faults is a function of accumulated stress. It changes from a few km/s during earthquakes to a few dozen km per day, month, or year during afterslip and inter-earthquake periods. The distribution of aftershocks in this model is consistent with both the Omori law for temporal distribution and a 1/r low for spatial distribution. We also discuss how the model explains the difference between the scaling laws for regular earthquakes and slow slip events, the periodicity of episodic tremor and slip (ETS), and the diverse tremor migration patterns during ETS events. Finally, we consider the nature of non-volcanic tremor, both ambient and accompanied by ETS. [1] Gershenzon N.I., Bykov V. G. and Bambakidis G., (2009) Strain waves, earthquakes, slow earthquakes, and afterslip in the framework of the Frenkel-Kontorova model, Physical Review E 79, 056601 [2] Gershenzon N.I., G. Bambakidis, E. Hauser, A. Ghosh, K.C. Creager (2011) Episodic tremors and slip in Cascadia in the framework of the Frenkel-Kontorova model. Geophys. Res. Lett., 38, L01309, doi:10.1029/2010GL045225 [3] Gershenzon N.I. & G. Bambakidis (2013) Transition from static to dynamic macroscopic friction in the framework of the Frenkel-Kontorova model. Tribology International, 61, 11-18, http://dx.doi.org/10.1016/j.triboint.2012.11.025

  3. Spatially Extended Relativistic Particles Out of Traveling Front Solutions of Sine-Gordon Equation in (1+2) Dimensions

    PubMed Central

    Zarmi, Yair

    2016-01-01

    Slower-than-light multi-front solutions of the Sine-Gordon in (1+2) dimensions, constructed through the Hirota algorithm, are mapped onto spatially localized structures, which emulate free, spatially extended, massive relativistic particles. A localized structure is an image of the junctions at which the fronts intersect. It propagates together with the multi-front solution at the velocity of the latter. The profile of the localized structure obeys the linear wave equation in (1+2) dimensions, to which a term that represents interaction with a slower-than-light, Sine-Gordon-multi-front solution has been added. This result can be also formulated in terms of a (1+2)-dimensional Lagrangian system, in which the Sine-Gordon and wave equations are coupled. Expanding the Euler-Lagrange equations in powers of the coupling constant, the zero-order part of the solution reproduces the (1+2)-dimensional Sine-Gordon fronts. The first-order part is the spatially localized structure. PACS: 02.30.Ik, 03.65.Pm, 05.45.Yv, 02.30.Ik. PMID:26930077

  4. Three-loop correction to the instanton density. II. The sine-Gordon potential

    NASA Astrophysics Data System (ADS)

    Escobar-Ruiz, M. A.; Shuryak, E.; Turbiner, A. V.

    2015-07-01

    In this second paper on quantum fluctuations near the classical instanton configurations [see M. A. Escobar-Ruiz, E. Shuryak, and A. V. Turbiner, preceding article, Phys. Rev. D 92, 025046 (2015)], we focus on another well-studied quantum-mechanical problem, the one-dimensional sine-Gordon potential (the Mathieu potential). Using only the tools from quantum field theory, the Feynman diagrams in the instanton background, we calculate the tunneling amplitude (the instanton density) to the three-loop order. The result confirms (to six significant figures) the one recently recalculated by G. V. Dunne and M. nsal, Phys. Rev. D 89, 105009 (2014) from the resurgence perspective. As in the double well potential case, we found that the largest contribution is given by the diagrams originating from the Jacobian. We again observe that in the three-loop case individual Feynman diagrams contain irrational contributions, while their sum does not.

  5. Modulational and numerical solutions for the steady discrete Sine-Gordon equation in two space dimensions

    NASA Astrophysics Data System (ADS)

    Cisneros, L. A.; Ize, J.; Minzoni, A. A.

    2009-07-01

    We develop a modulation theory based on a suitably averaged Lagrangian for steady solutions of the Sine-Gordon equation in a two dimensional lattice. These lump solutions are nonzero in circular or polygonal regions and zero elsewhere. The modulation theory gives approximate solutions away from small perturbations of the exact anti-continuum solutions for both radial and polygonal solutions. We show how the Peierls-Nabarro potential determines the shape of the boundary between excited sites and the zero solution. These solutions are compared with the corresponding numerical solutions and significant agreement is found. Moreover, we show that solutions with a large radius (more than sixteen lattice sites) can be explained using a continuous trial function for the averaged Lagrangian, while smaller polygonal solutions can be constructed using a trial function, which takes into account the angular variation of the boundary imposed by the lattice. Finally, the ideas of equivariant bifurcation theory are used to obtain a full numerical description of the solution branches as functions of the coupling parameter between neighboring sites. The results of this work can be used to study steady solutions for other types of lattice equations.

  6. Classical and quantum solitons in the symmetric space sine-Gordon theories

    NASA Astrophysics Data System (ADS)

    Hollowood, Timothy J.; Luis Miramontes, J.

    2011-04-01

    We construct the soliton solutions in the symmetric space sine-Gordon theories. The latter are a series of integrable field theories in 1 + 1-dimensions which are associated to a symmetric space F/ G, and are related via the Pohlmeyer reduction to theories of strings moving on symmetric spaces. We show that the solitons are kinks that carry an internal moduli space that can be identified with a particular co-adjoint orbit of the unbroken subgroup H ? G. Classically the solitons come in a continuous spectrum which encompasses the perturbative fluctuations of the theory as the kink charge becomes small. We show that the solitons can be quantized by allowing the collective coordinates to be time-dependent to yield a form of quantum mechanics on the co-adjoint orbit. The quantum states correspond to symmetric tensor representations of the symmetry group H and have the interpretation of a fuzzy geometric version of the co-adjoint orbit. The quantized finite tower of soliton states includes the perturbative modes at the base.

  7. Specific sine-Gordon soliton dynamics in the presence of external driving forces

    NASA Astrophysics Data System (ADS)

    Reinisch, Gilbert; Fernandez, Jean Claude

    1981-07-01

    We consider the acceleration of a single sine-Gordon (SG) soliton kink wave by an external time-dependent force ?(t), first without any dissipation, and then in the presence of a weak damping effect. We use the method of Fogel, Trullinger, Bishop, and Krumhansl [FTBK,

    Phys. Rev. B 45, 1578 (1977)]
    which consists in perturbing the SG equation about its kink solution and solving the resulting linear inhomogeneous equation for the perturbation function by expanding it in the complete set of eigenfunctions of the Schrdinger operator with potential 1-2 2x. Our results concerning the accelerated soliton dynamics strongly disagree with the FTBK conclusion that the soliton should undergo an acceleration proportional to ? (this is the so-called Newtonian dynamical behavior of SG soliton, which is also predicted by all existing perturbation theories dealing with the perturbed SG equation). On the contrary, we find that this Newtonian acceleration is exactly balanced by a reaction effect of the continuous phonon spectrum excited by the external force ?, upon the moving kink, so that there is no soliton acceleration at all within the frame of this linear perturbation theory, i.e., for small time values. Actually, we show by the simple example of a static external force that the acceleration of an initially static kink is a higher-order effect (proportional to ?t2, where t is the time, instead of being constant and proportional to ?). We emphasize that this last result has already been checked by numerical experiments and show, both by theory and by numerical simulations, that it does not qualitatively change when a small damping effect is taken into account.

  8. Various Types of Kink and Bright Resonant Soliton Solutions for the (2+1)-Dimensional Double sine-Gordon Equation

    NASA Astrophysics Data System (ADS)

    Lin, Ji; Huang, Guang-Qiao; Chen, Wei-Xiong

    2015-07-01

    The algebraic mapping relations between the (2+1)-dimensional double sine-Gordon equation and the cubic nonlinear Klein-Gordon equation are constructed. Many new types of two-dimensional resonant kink, bright soliton and solitoff solutions are obtained, such as broken line shape, V shape, snake shape and M shape solitary waves, Zigzag-curve type, ? shape, peroidic-curve type, oscillatory Arch-type and parabolic shape bright soliton waves. We also investigate the propagating properties of some soliton solutions. Supported by the Natural Science Foundation of Zhejiang Province under Grant No. LZ15A050001 and the National Natural Science Foundation of China under Grant No. 11175158

  9. Connections defining representations of zero curvature and the solitons of sine-Gordon and Korteweg-de Vries equations

    NASA Astrophysics Data System (ADS)

    Rybnikov, A. K.

    2011-06-01

    It is claimed that solutions of travelling-wave type (and, in particular, soliton solutions) of partial differential equations can be created by using connections defining representations of zero curvature. In this paper, we construct solitons of the sine-Gordon and Korteweg-de Vries equations. By previous results of the author, the connections defining representations of zero curvature for a given differential equation generate Bcklund transformations for this equation. It can be shown that the well-known Lax system (the so-called Lax pair) for the Korteweg-de Vries equation is a special case of a Bcklund system (i.e., the system of partial differential equations defining a Bcklund transformation). Note that the creation of solitons by means of the inverse scattering method is in fact a creation of solitons by means of the Lax system (without using connections defining the representations of zero curvature from the very beginning). Moreover, the inverse scattering method is essentially more labor-consuming than the method suggested in the present paper. Further, it is not required to involve any physical notions when using the suggested method. In the final section of the paper, we consider the so-called 2-soliton solutions of sine-Gordon and Korteweg de Vries equations. Here we systematically use the invariant analytic method developed by G. F. Laptev, which is well-known in differential geometry under the title of Cartan-Laptev method.

  10. Linear stability of spherically symmetric and wormhole solutions supported by the sine-Gordon ghost scalar field

    SciTech Connect

    Dzhunushaliev, Vladimir; Folomeev, Vladimir; Singleton, Douglas; Myrzakulov, Ratbay

    2010-08-15

    In this paper we investigate wormhole and spherically symmetric solutions in four-dimensional gravity plus a matter source consisting of a ghost scalar field with a sine-Gordon potential. For the wormhole solutions we also include the possibility of electric and/or magnetic charges. For both types of solutions we perform a linear stability analysis and show that the wormhole solutions are stable and that when one turns on the electric and/or magnetic field the solution remains stable. The linear stability analysis of the spherically symmetric solutions indicates that they can be stable or unstable depending on one of the parameters of the system. This result for the spherically symmetric solution is nontrivial since a previous investigation of four-dimensional gravity plus a ghost scalar field with a {lambda}{phi}{sup 4} interaction found only unstable spherically symmetric solutions. Both the wormhole and spherically symmetric solutions presented here asymptotically go to anti-de Sitter space-time.

  11. Connection between the infinite sequence of Lie-Bcklund symmetries of the Korteweg-de Vries and sine-Gordon equations

    NASA Astrophysics Data System (ADS)

    Kaliappan, P.; Lakshmanan, M.

    1982-03-01

    From the observation that the infinite sequence of Lie-Bcklund symmetries of the potential modified Kortweg-deVries (PMK-dV) and the sine-Gordon (s-G) equations are identical, it is shown that there exists a simple connection between the Lie-Bcklund symmetries (written in the form of evolution equations) of the Korteweg-deVries (K-dV) and s-G equations. Further, this connection is similar to the one obtained by Chodos for the conserved quantities of K-dV and s-G equations. We also point out that the result of Chodos can be realized from the equality of conserved densities of PMK-dV and s-G systems.

  12. Sine-Gordon Equation in (1+2) and (1+3) dimensions: Existence and Classification of Traveling-Wave Solutions

    PubMed Central

    Zarmi, Yair

    2015-01-01

    The (1+1)-dimensional Sine-Gordon equation passes integrability tests commonly applied to nonlinear evolution equations. Its kink solutions (one-dimensional fronts) are obtained by a Hirota algorithm. In higher space-dimensions, the equation does not pass these tests. Although it has been derived over the years for quite a few physical systems that have nothing to do with Special Relativity, the Sine-Gordon equation emerges as a non-linear relativistic wave equation. This opens the way for exploiting the tools of the Theory of Special Relativity. Using no more than the relativistic kinematics of tachyonic momentum vectors, from which the solutions are constructed through the Hirota algorithm, the existence and classification of N-moving-front solutions of the (1+2)- and (1+3)-dimensional equations for all N ≥ 1 are presented. In (1+2) dimensions, each multi-front solution propagates rigidly at one velocity. The solutions are divided into two subsets: Solutions whose velocities are lower than a limiting speed, c = 1, or are greater than or equal to c. To connect with concepts of the Theory of Special Relativity, c will be called “the speed of light.” In (1+3)-dimensions, multi-front solutions are characterized by spatial structure and by velocity composition. The spatial structure is either planar (rotated (1+2)-dimensional solutions), or genuinely three-dimensional – branes. Planar solutions, propagate rigidly at one velocity, which is lower than, equal to, or higher than c. Branes must contain clusters of fronts whose speed exceeds c = 1. Some branes are “hybrids”: different clusters of fronts propagate at different velocities. Some velocities may be lower than c but some must be equal to, or exceed, c. Finally, the speed of light cannot be approached from within the subset of slower-than-light solutions in both (1+2) and (1+3) dimensions. PMID:26020922

  13. Sine-Gordon Equation in (1+2) and (1+3) dimensions: Existence and Classification of Traveling-Wave Solutions.

    PubMed

    Zarmi, Yair

    2015-01-01

    The (1+1)-dimensional Sine-Gordon equation passes integrability tests commonly applied to nonlinear evolution equations. Its kink solutions (one-dimensional fronts) are obtained by a Hirota algorithm. In higher space-dimensions, the equation does not pass these tests. Although it has been derived over the years for quite a few physical systems that have nothing to do with Special Relativity, the Sine-Gordon equation emerges as a non-linear relativistic wave equation. This opens the way for exploiting the tools of the Theory of Special Relativity. Using no more than the relativistic kinematics of tachyonic momentum vectors, from which the solutions are constructed through the Hirota algorithm, the existence and classification of N-moving-front solutions of the (1+2)- and (1+3)-dimensional equations for all N ≥ 1 are presented. In (1+2) dimensions, each multi-front solution propagates rigidly at one velocity. The solutions are divided into two subsets: Solutions whose velocities are lower than a limiting speed, c = 1, or are greater than or equal to c. To connect with concepts of the Theory of Special Relativity, c will be called "the speed of light." In (1+3)-dimensions, multi-front solutions are characterized by spatial structure and by velocity composition. The spatial structure is either planar (rotated (1+2)-dimensional solutions), or genuinely three-dimensional--branes. Planar solutions, propagate rigidly at one velocity, which is lower than, equal to, or higher than c. Branes must contain clusters of fronts whose speed exceeds c = 1. Some branes are "hybrids": different clusters of fronts propagate at different velocities. Some velocities may be lower than c but some must be equal to, or exceed, c. Finally, the speed of light cannot be approached from within the subset of slower-than-light solutions in both (1+2) and (1+3) dimensions. PMID:26020922

  14. Thermal and electromagnetic properties of Bi2Sr2CaCu2O8 intrinsic Josephson junction stacks studied via one-dimensional coupled sine-Gordon equations

    NASA Astrophysics Data System (ADS)

    Rudau, F.; Tsujimoto, M.; Gross, B.; Judd, T. E.; Wieland, R.; Goldobin, E.; Kinev, N.; Yuan, J.; Huang, Y.; Ji, M.; Zhou, X. J.; An, D. Y.; Ishii, A.; Mints, R. G.; Wu, P. H.; Hatano, T.; Wang, H. B.; Koshelets, V. P.; Koelle, D.; Kleiner, R.

    2015-03-01

    We used one-dimensional coupled sine-Gordon equations combined with heat diffusion equations to numerically investigate the thermal and electromagnetic properties of a 300 ? m long intrinsic Josephson junction stack consisting of N =700 junctions. The junctions in the stack are combined with M segments where we assume that inside a segment all junctions behave identically. Most simulations are for M =20 . For not too high bath temperatures there is the appearance of a hot spot at high-bias currents. In terms of electromagnetic properties, robust standing-wave patterns appear in the current density and electric field distributions. These patterns come together with vortex/antivortex lines across the stack that correspond to ? -kink states, discussed before in the literature for a homogeneous temperature distribution in the stack. We also discuss scaling of the thermal and electromagnetic properties with M , on the basis of simulations with M between 10 and 350.

  15. Semiholographic model revisited

    NASA Astrophysics Data System (ADS)

    Cárdenas, Víctor H.; Magaña, Juan; Villanueva, J. R.

    2014-03-01

    In a recent work, Zhang, Li and Noh proposed a model for dark energy assuming that this component strictly obeys the holographic principle. They performed a dynamical system analysis, finding a scaling solution which is helpful to solve the coincidence problem. However, they need explicitly a cosmological constant. In this paper, we derive an explicit analytical solution, without Λ, that shows agreement with the supernovae data. However, this solution is not physical because it violates all the energy conditions.

  16. Quantum complex sine-Gordon dressed boundaries

    NASA Astrophysics Data System (ADS)

    Bowcock, P.; Umpleby, J. M.

    2008-11-01

    In this paper we investigate the quantum reflection factor for the CSG dressed boundary, previously constructed by dressing the Dirichlet boundary with the integrable CSG defect [1]. We analyse classical bound states and use semi-classical methods to investigate the quantum boundary spectrum. We conjecture a fully quantum reflection matrix for a particle reflecting from an unexcited boundary. By using the reflection and boundary bootstrap equations, the reflection matrix for a charge Q = +n soliton reflecting from the mth excited boundary is constructed. Evidence supporting our conjecture is given by checking that the bootstrap closes and that the reflection matrices agrees with known results in the classical limit. A partial analysis of the poles in the reflection matrices which arise from Coleman-Thun diagrams is given.

  17. Bayesian Constrained Local Models Revisited.

    PubMed

    Martins, Pedro; Henriques, Jo Ao F; Caseiro, Rui; Batista, Jorge

    2016-04-01

    This paper presents a novel Bayesian formulation for aligning faces in unseen images. Our approach revisits the Constrained Local Models (CLM) formulation where an ensemble of local feature detectors are constrained to lie within the subspace spanned by a Point Distribution Model (PDM). Fitting such a model to an image typically involves two main steps: a local search using a detector, obtaining response maps for each landmark (likelihood term) and a global optimization that finds the PDM parameters that jointly maximize all the detections at once. The so-called global optimization can be posed as a Bayesian inference problem, where the posterior distribution of the shape (and pose) parameters can be inferred in a maximum a posteriori (MAP) sense. This work introduces an extended Bayesian global optimization strategy that includes two novel additions: (1) to perform second order updates of the PDM parameters (accounting for their covariance) and (2) to model the underlying dynamics of the shape variations, encoded in the prior term, by using recursive Bayesian estimation. Extensive evaluations were performed against state-of-the-art methods on several standard datasets (IMM, BioID, XM2VTS, LFW and FGNET Talking Face). Results show that the proposed approach significantly increases the fitting performance. PMID:26959675

  18. Configurational entropy in brane-world models

    NASA Astrophysics Data System (ADS)

    Correa, R. A. C.; da Rocha, Roldo

    2015-11-01

    In this work we investigate the entropic information on thick brane-world scenarios and its consequences. The brane-world entropic information is studied for the sine-Gordon model and hence the brane-world entropic information measure is shown to be an accurate way for providing the most suitable range for the bulk AdS curvature, in particular from the informational content of physical solutions. Besides, the brane-world configurational entropy is employed to demonstrate a high organisational degree in the structure of the configuration of the system, for large values of a parameter of the sine-Gordon model but the one related to the AdS curvature. The Gleiser and Stamatopoulos procedure is finally applied in order to achieve a precise correlation between the energy of the system and the brane-world configurational entropy.

  19. Quantum mass shift of the soliton in the Skyrme model

    SciTech Connect

    Livne, H. )

    1993-02-01

    The quantum mass shift of the soliton in the Skyrme model has been calculated from all nonzero modes. The calculations were carried out using a method applied earlier to the sine-Gordon model. The mass shifts do not depend on the baryonic spin, therefore they are the same for the nucleon and the [Delta]. Our model parameters are the pion decay constant [ital F][sub [pi

  20. Conceptual Foundations of Soliton Versus Particle Dualities Toward a Topological Model for Matter

    NASA Astrophysics Data System (ADS)

    Kouneiher, Joseph

    2016-02-01

    The idea that fermions could be solitons was actually confirmed in theoretical models in 1975 in the case when the space-time is two-dimensional and with the sine-Gordon model. More precisely S. Coleman showed that two different classical models end up describing the same fermions particle, when the quantum theory is constructed. But in one model the fermion is a quantum excitation of the field and in the other model the particle is a soliton. Hence both points of view can be reconciliated.The principal aim in this paper is to exhibit a solutions of topological type for the fermions in the wave zone, where the equations of motion are non-linear field equations, i.e. using a model generalizing sine- Gordon model to four dimensions, and describe the solutions for linear and circular polarized waves. In other words, the paper treat fermions as topological excitations of a bosonic field.

  1. Complete integrability of the supersymmetric (cos phi)/sub 2/ model

    SciTech Connect

    Kulish, P.P.; Tsyplyaev, S.A.

    1987-05-20

    Complete integrability of the supersymmetric two-dimensional sine-Gordon field-theoretical model is proved in the framework of the Hamiltonian interpretation of the inverse problem method. The classical r-matrix of this model is computed and shown to be equivalent to the r-matrix of the Grassmann Thirring model. Creation-annihilation variables are constructed and the elementary excitation spectrum is determined.

  2. Complete integrability of the supersymmetric model (cos phi)/sub ell/

    SciTech Connect

    Kulish, P.P.; Tsyplyaev, S.A.

    1986-09-10

    Complete integrability of the supersymmetric, two-dimensional sine-Gordon model of field theory within the framework of the Hamiltonian interpretation of the method of the inverse problem is proved. The classical r-matrix of the model is computed, and its equivalence to the r-matrix the Grassmann Thirring model is established. Variables of creation-annihilation type are constructed, and the spectrum of elementary excitations of the system is obtained.

  3. Revisiting the standard solar model

    SciTech Connect

    Turck-Chieze, S.; Cahen, S.; Casse, M.; Doom, C.

    1988-12-01

    The mutual consistency between standard solar models is studied based on the recent Los Alamos opacity tables. Satisfactory agreement is found among these models concerning the helium content and the neutrino capture rates. The reference model leads to a solar helium content of 0.276 + or - 0.012 by mass fraction. 75 references.

  4. Isgur-Karl model revisited

    SciTech Connect

    Galeta, Leonardo; Pirjol, Dan; Schat, Carlos

    2009-12-01

    We show how to match the Isgur-Karl model to the spin-flavor quark operator expansion used in the 1/N{sub c} studies of the nonstrange negative parity L=1 excited baryons. Using the transformation properties of states and interactions under the permutation group S{sub 3} we are able to express the operator coefficients as overlap integrals, without making any assumption on the spatial dependence of the quark wave functions. The general mass operator leads to parameter free mass relations and constraints on the mixing angles that are valid beyond the usual harmonic oscillator approximation. The Isgur-Karl model with harmonic oscillator wave functions provides a simple counterexample that demonstrates explicitly that the alternative operator basis for the 1/N{sub c} expansion for excited baryons recently proposed by Matagne and Stancu is incomplete.

  5. The sausage sigma model revisited

    NASA Astrophysics Data System (ADS)

    Suneeta, Vardarajan

    2015-06-01

    Fateev’s sausage sigma models in two and three dimensions are known to be integrable. We study their stability under renormalization group (RG) flow in the target space by using results from the mathematics of Ricci flow. We show that the three-dimensional sausage is unstable, whereas the two-dimensional sausage appears to be stable at least at leading order as it approaches the sphere. We speculate that the stability results obtained are linked to the classification of ancient solutions to Ricci flow (i.e., sigma models that are nonperturbative in the infrared regime) in two and three dimensions. We also describe a class of perturbations of the three-dimensional sausage (with the same continuous symmetries) which remarkably decouple. This indicates that there could be a new solution to RG flow, which is described at least perturbatively as a deformation of the sausage.

  6. Fusion by Diffusion Model Revisited

    NASA Astrophysics Data System (ADS)

    Cap, T.; Siwek-Wilczyńska, K.; Wilczyński, J.

    A complete set of 27 excitation functions for synthesis of superheavy nuclei produced in cold fusion reactions was analyzed in terms of the "Fusion by Diffusion Model" of Światecki et al., modified to account for the angular momentum dependence of the fusion hindrance factor. The data on cold fusion reactions originate from experiments carried out at GSI Darmstadt, RIKEN Tokyo and LBNL Berkeley in which 208Pb and 209Bi targets were bombarded with the variety of projectiles ranging from 48,50Ti to 70Zn.

  7. The abelian confinement mechanism revisited: New aspects of the GeorgiGlashow model

    SciTech Connect

    Anber, Mohamed M.

    2014-02-15

    The confinement problem remains one of the most difficult problems in theoretical physics. An important step toward the solution of this problem is Polyakovs work on abelian confinement. The GeorgiGlashow model is a natural testing ground for this mechanism which has been surprising us by its richness and wide applicability. In this work, we shed light on two new aspects of this model in 2+1 D. First, we develop a many-body description of the effective degrees of freedom. Namely, we consider a non-relativistic gas of W-bosons in the background of monopoleinstanton plasma. Many-body treatment is a standard toolkit in condensed matter physics. However, we add a new twist by supplying the monopoleinstantons as external background field. Using this construction along with a mean-field approximation, we calculate the form of the potential between two electric probes as a function of their separation. This potential is expressed in terms of the Meijer-G function which interpolates between logarithmic and linear behavior at small and large distances, respectively. Second, we develop a systematic approach to integrate out the effect of the W-bosons at finite temperature in the range 0?Tmodel. Using a heat kernel expansion that takes into account the non-trivial thermal holonomy, we show that the partition function describes a three-dimensional two-component Coulomb gas. We repeat our analysis using the many-body description which yields the same result and provides a check on our formalism. At temperatures close to the deconfinement temperature, the gas becomes essentially two-dimensional recovering the partition function of the dual sine-Gordon model that was considered in a previous work. -- Highlights: We consider the problem of abelian confinement in the GeorgiGlashow model from a new perspective. We develop a many-body description of the degrees of freedom of this model in the background of monopoleinstanton plasma. We use the many-body formalism to find an analytic expression of the potential between two probes at zero temperature. We also use a systematic approach to integrate out the W-bosons starting from the full relativistic partition function. This results in a three-dimensional two-component Coulomb gas with long range and AharonovBohm phase interaction.

  8. A Multi-Level Model of Moral Functioning Revisited

    ERIC Educational Resources Information Center

    Reed, Don Collins

    2009-01-01

    The model of moral functioning scaffolded in the 2008 "JME" Special Issue is here revisited in response to three papers criticising that volume. As guest editor of that Special Issue I have formulated the main body of this response, concerning the dynamic systems approach to moral development, the problem of moral relativism and the role of

  9. Topological Twisted Sigma Model with H-flux Revisited

    SciTech Connect

    Chuang, Wu-yen

    2006-08-18

    In this paper we revisit the topological twisted sigma model with H-flux. We explicitly expand and then twist the worldsheet Lagrangian for bi-Hermitian geometry. we show that the resulting action consists of a BRST exact term and pullback terms, which only depend on one of the two generalized complex structures and the B-field. We then discuss the topological feature of the model.

  10. Quantum projectors and local operators in lattice integrable models

    NASA Astrophysics Data System (ADS)

    Oota, Takeshi

    2004-01-01

    In the framework of the quantum inverse scattering method, we consider a problem of constructing local operators for one-dimensional quantum integrable models, especially for the lattice versions of the nonlinear Schrdinger and sine-Gordon models. We show that a certain class of local operators can be constructed from the matrix elements of the monodromy matrix in a simple way. They are closely related to the quantum projectors and have nice commutation relations with half of the matrix elements of the elementary monodromy matrix. The form factors of these operators can be calculated by using the standard algebraic Bethe ansatz techniques.

  11. Models for optical solitons in the two-cycle regime

    SciTech Connect

    Leblond, H.; Sanchez, F.

    2003-01-01

    We derive model equations for optical pulse propagation in a medium described by a two-level Hamiltonian, without the use of the slowly varying envelope approximation. Assuming that the resonance frequency of the two-level atoms is either well above or well below the inverse of the characteristic duration of the pulse, we reduce the propagation problem to a modified Korteweg-de Vries or a sine-Gordon equation. We exhibit analytical solutions of these equations which are rather close in shape and spectrum to pulses in the two-cycle regime produced experimentally, which shows that soliton-type propagation of the latter can be envisaged.

  12. Extended primitive models of water revisited

    NASA Astrophysics Data System (ADS)

    Strnad, Martin; Nezbeda, Ivo

    A 4-site extended primitive model of water descending from the TIP4 potential has been reexamined over a range of the model parameters. It has been found, in contrast to recently reported results (Nezbeda, I., and Slovak, J., 1997, Molec. Phys. , 90, 353), that the model clearly is superior to 5-site models descending from the ST2 potential and yields the liquid structure in very good agreement with that of real water.

  13. Morse's Markov Model of Book Use Revisited.

    ERIC Educational Resources Information Center

    Beheshti, Jamshid; Tague, Jean M.

    1984-01-01

    Utilizing 11 years of University of Saskatchewan circulation transactions, it is shown that P. M. Morse's Markov model of book use fits approximately 99 percent of data for whole collection and for three subject areas; contrary to his assumptions, one of the model's parameters is time dependent. Thirteen references are included. (EJS)

  14. Sverdlovsk revisited: modeling human inhalation anthrax.

    PubMed

    Wilkening, Dean A

    2006-05-16

    Several models have been proposed for the dose-response function and the incubation period distribution for human inhalation anthrax. These models give very different predictions for the severity of a hypothetical bioterror attack, when an attack might be detected from clinical cases, the efficacy of medical intervention and the requirements for decontamination. Using data from the 1979 accidental atmospheric release of anthrax in Sverdlovsk, Russia, and limited nonhuman primate data, this paper eliminates two of the contending models and derives parameters for the other two, thereby narrowing the range of models that accurately predict the effects of human inhalation anthrax. Dose-response functions that exhibit a threshold for infectivity are contraindicated by the Sverdlovsk data. Dose-dependent incubation period distributions explain the 10-day median incubation period observed at Sverdlovsk and the 1- to 5-day incubation period observed in nonhuman primate experiments. PMID:16679412

  15. Complex trait architecture: the pleiotropic model revisited

    PubMed Central

    North, T.-L.; Beaumont, M. A.

    2015-01-01

    There is currently much debate about how much the genetic heritability of complex traits is due to very rare alleles. This issue is important because it determines sampling strategies for genetic association studies. Several recent theoretical papers based on a pleiotropic model for trait evolution suggest that it is possible that a large proportion of the genetic variance could be explained by rare alleles. This model assumes that mutations with a large effect on fitness also tend to have large positive or negative effects on phenotypic traits. We show that conclusions based on standard diffusion results are generally applicable to simulations of whole genomes with overlapping generations in a finite population, although the variance contribution of rare alleles is somewhat smaller than theoretical predictions. We show that under many scenarios the pleiotropic model predicts trait distributions that are unrealistically leptokurtic. We argue that this imposes a limit on the relationship between fitness and trait effects. PMID:25792462

  16. Potts-model critical manifolds revisited

    NASA Astrophysics Data System (ADS)

    Scullard, Christian R.; Lykke Jacobsen, Jesper

    2016-03-01

    We compute critical polynomials for the q-state Potts model on the Archimedean lattices, using a parallel implementation of the algorithm of Jacobsen (2014 J. Phys. A: Math. Theor 47 135001) that gives us access to larger sizes than previously possible. The exact polynomials are computed for bases of size 6 × 6 unit cells, and the root in the temperature variable v={{{e}}}K-1 is determined numerically at q = 1 for bases of size 8 × 8. This leads to improved results for bond percolation thresholds, and for the Potts-model critical manifolds in the real (q, v) plane. In the two most favourable cases, we find now the kagome-lattice threshold to eleven digits and that of the (3,{12}2) lattice to thirteen. Our critical manifolds reveal many interesting features in the antiferromagnetic region of the Potts model, and determine accurately the extent of the Berker–Kadanoff phase for the lattices studied.

  17. The Bonn nuclear quark model revisited

    SciTech Connect

    Providencia, Constanca; Providencia, Joao da Cordeiro, Flavio; Yamamura, Masatoshi; Tsue, Yasuhiko; Nishiyama, Seiya

    2009-08-15

    We present the exact solutions to the equations of the lowest energy states of the colored and color-symmetric sectors of the Bonn quark model, which is SU(3) symmetric and is defined in terms of an effective pairing force with su(4) algebraic structure. We show that the groundstate of the model is not color symmetrical except for a narrow interval in the range of possible quark numbers. We also study the performance of the Glauber coherent state, as well as of superconducting states of the BCS type, with respect to the description, not only of the absolute (colored) groundstate, but also of the minimum energy state of the color-symmetrical sector, finding that it is remarkably good. We use the model to discuss, in a schematic context, some controversial aspects of the conventional treatment of color superconductivity.

  18. Diffusion approximation of neuronal models revisited.

    PubMed

    Cupera, Jakub

    2014-02-01

    Leaky integrate-and-fire neuronal models with reversal potentials have a number of different diffusion approximations, each depending on the form of the amplitudes of the postsynaptic potentials. Probability distributions of the first-passage times of the membrane potential in the original model and its diffusion approximations are numerically compared in order to find which of the approximations is the most suitable one. The properties of the random amplitudes of postsynaptic potentials are discussed. It is shown on a simple example that the quality of the approximation depends directly on them. PMID:24245676

  19. Crime, criminals, and cures: medical model revisited.

    PubMed

    Sampson, R J

    2000-06-01

    David Lykken's target article assesses the causes of crime and advocates a controversial "cure"--parental licensure. Although Lykken gets many of the facts about criminals right, ultimately the disease metaphor breaks down. Crime requires three things--motivated offenders ("criminals"), suitable targets or victims, and the absence of capable guardians to prevent the act. Typical of medical model approaches, failure to consider the convergence in time and space of the three necessary elements for crime results in a misdiagnosis. In this invited commentary, I briefly note three reasons why Lykken's cure, along with the medical model in general, is unlikely to bear fruit. PMID:10831313

  20. The Hopfield model revisited: covariance and quantization

    NASA Astrophysics Data System (ADS)

    Belgiorno, F.; Cacciatori, S. L.; Dalla Piazza, F.

    2016-01-01

    There are several possible applications of quantum electrodynamics in dielectric media which require a quantum description for the electromagnetic field interacting with matter fields. The associated quantum models can refer to macroscopic electromagnetic fields or, alternatively, to mesoscopic fields (polarization fields) describing an effective interaction between electromagnetic field and matter fields. We adopt the latter approach, and focus on the Hopfield model for the electromagnetic field in a dielectric dispersive medium in a framework in which spacetime dependent mesoscopic parameters occur, like susceptibility, matter resonance frequency, and also coupling between electromagnetic field and polarization field. Our most direct goal is to describe in a phenomenological way a spacetime varying dielectric perturbation induced by means of the Kerr effect in nonlinear dielectric media. This extension of the model is implemented by means of a Lorentz-invariant Lagrangian which, for constant microscopic parameters, and in the rest frame, coincides with the standard one. Moreover, we deduce a covariant scalar product and provide a canonical quantization scheme which takes into account the constraints implicit in the model. Examples of viable applications are indicated.

  1. Density waves in the Calogero model - revisited

    SciTech Connect

    Bardek, V. Feinberg, J. Meljanac, S.

    2010-03-15

    The Calogero model bears, in the continuum limit, collective excitations in the form of density waves and solitary modulations of the density of particles. This sector of the spectrum of the model was investigated, mostly within the framework of collective-field theory, by several authors, over the past 15 years or so. In this work we shall concentrate on periodic solutions of the collective BPS-equation (also known as 'finite amplitude density waves'), as well as on periodic solutions of the full static variational equations which vanish periodically (also known as 'large amplitude density waves'). While these solutions are not new, we feel that our analysis and presentation add to the existing literature, as we explain in the text. In addition, we show that these solutions also occur in a certain two-family generalization of the Calogero model, at special points in parameter space. A compendium of useful identities associated with Hilbert transforms, including our own proofs of these identities, appears in Appendix A. In Appendix B we also elucidate in the present paper some fine points having to do with manipulating Hilbert-transforms, which appear ubiquitously in the collective field formalism. Finally, in order to make this paper self-contained, we briefly summarize in Appendix C basic facts about the collective field formulation of the Calogero model.

  2. Revisiting the vanishing refuge model of diversification.

    PubMed

    Damasceno, Roberta; Strangas, Maria L; Carnaval, Ana C; Rodrigues, Miguel T; Moritz, Craig

    2014-01-01

    Much of the debate around speciation and historical biogeography has focused on the role of stabilizing selection on the physiological (abiotic) niche, emphasizing how isolation and vicariance, when associated with niche conservatism, may drive tropical speciation. Yet, recent re-emphasis on the ecological dimensions of speciation points to a more prominent role of divergent selection in driving genetic, phenotypic, and niche divergence. The vanishing refuge model (VRM), first described by Vanzolini and Williams (1981), describes a process of diversification through climate-driven habitat fragmentation and exposure to new environments, integrating both vicariance and divergent selection. This model suggests that dynamic climates and peripheral isolates can lead to genetic and functional (i.e., ecological and phenotypic) diversity, resulting in sister taxa that occupy contrasting habitats with abutting distributions. Here, we provide predictions for populations undergoing divergence according to the VRM that encompass habitat dynamics, phylogeography, and phenotypic differentiation across populations. Such integrative analyses can, in principle, differentiate the operation of the VRM from other speciation models. We applied these principles to a lizard species, Coleodactylus meridionalis, which was used to illustrate the model in the original paper. We incorporate data on inferred historic habitat dynamics, phylogeography and thermal physiology to test for divergence between coastal and inland populations in the Atlantic Forest of Brazil. Environmental and genetic analyses are concordant with divergence through the VRM, yet physiological data are not. We emphasize the importance of multidisciplinary approaches to test this and alternative speciation models while seeking to explain the extraordinarily high genetic and phenotypic diversity of tropical biomes. PMID:25374581

  3. Revisiting the vanishing refuge model of diversification

    PubMed Central

    Damasceno, Roberta; Strangas, Maria L.; Carnaval, Ana C.; Rodrigues, Miguel T.; Moritz, Craig

    2014-01-01

    Much of the debate around speciation and historical biogeography has focused on the role of stabilizing selection on the physiological (abiotic) niche, emphasizing how isolation and vicariance, when associated with niche conservatism, may drive tropical speciation. Yet, recent re-emphasis on the ecological dimensions of speciation points to a more prominent role of divergent selection in driving genetic, phenotypic, and niche divergence. The vanishing refuge model (VRM), first described by Vanzolini and Williams (1981), describes a process of diversification through climate-driven habitat fragmentation and exposure to new environments, integrating both vicariance and divergent selection. This model suggests that dynamic climates and peripheral isolates can lead to genetic and functional (i.e., ecological and phenotypic) diversity, resulting in sister taxa that occupy contrasting habitats with abutting distributions. Here, we provide predictions for populations undergoing divergence according to the VRM that encompass habitat dynamics, phylogeography, and phenotypic differentiation across populations. Such integrative analyses can, in principle, differentiate the operation of the VRM from other speciation models. We applied these principles to a lizard species, Coleodactylus meridionalis, which was used to illustrate the model in the original paper. We incorporate data on inferred historic habitat dynamics, phylogeography and thermal physiology to test for divergence between coastal and inland populations in the Atlantic Forest of Brazil. Environmental and genetic analyses are concordant with divergence through the VRM, yet physiological data are not. We emphasize the importance of multidisciplinary approaches to test this and alternative speciation models while seeking to explain the extraordinarily high genetic and phenotypic diversity of tropical biomes. PMID:25374581

  4. 'Andesite Model' of Continental Crust Formation Revisited

    NASA Astrophysics Data System (ADS)

    Gill, J. B.

    2014-12-01

    Fifty years ago, Ross Taylor observed that the chemical composition of average continental crust and orogenic andesites were similar for many major and trace elements. However, almost immediately it was recognized that this generalization does not apply to many oceanic island arcs because they are too mafic and too depleted in the most incompatible elements, including K, Th, and U. Although intra-crustal differentiation and delamination might produce sufficiently evolved middle and lower crust, it is an inefficient way to increase incompatible element concentrations in intermediate magma. There are alternative processes. First, because the vast majority of arc rocks are volcaniclastic sediments rather than igneous rocks, mechanical mixing is a dominant process during arc evolution. Although its effects are similar to those of magma mixing and assimilation, it has fewer physical constraints and is more likely. The finer-grained the sediment, the more mixing is likely. Drilling in the Izu arc shows that the majority of the sediment is andesitic mud even though the majority of lavas are basalt and rhyolite. Volcaniclastic sediments may be a better match to continental crust than the lavas that were the original basis of the andesite model. Second, some reararc lavas and sediments are more like continental crust than those from volcanic fronts, and reararc crust is at least as thick. Third, aeolian dust in arc muds may be a larger mass fraction of recycled continental crust in oceanic arcs than the subducted pelagic sediment component in arc magmas. The net effect of these features adds nuance to the andesite model but is not enough to overcome the deficit of incompatible elements in Cenozoic oceanic arcs. Accreting them still makes the continents less continental in composition.

  5. Neural network modelling of CIMIS-ET0 (revisited)

    NASA Astrophysics Data System (ADS)

    Abrahart, R. J.; Ghani, N. Ab

    2009-04-01

    This paper will revisit the use of four independent hydrometeorological variables to predict 'reference crop evapotranspiration' in a neural network model - calculated as CIMIS-ET0 (Kisi, 2006; Aytek et al., 2008). The two earlier studies are coalesced and their published findings positioned in a broader environmental modelling context. Four models developed on similar datasets are compared and contrasted in the current exercise: a multiple linear regression model (MLIN: Pearson, 1896), a piecewise multiple linear regression model (M5 Model Tree; M5MT: Quinlan, 1992; Wang & Witten, 1997) and two neural network models developed on different optimisation algorithms - Conjugate Gradient (CGNN: Hestenes & Stiefel, 1952) and Levenberg-Marquet (LMNN: Levenberg, 1944; Marquardt, 1963). The results are presented using residual scatterplots so that the exact nature of the each individual modelling solution can be determined: permitting outputs to be interpreted in terms of structures, symmetries, orientations, local features and outliers. The reported inspection and interpretation of plots is matched against a selection of traditional numerical modelling statistics that were computed on HydroTest (http://www.hydrotest.org.uk; Dawson et al., 2007). The reported closeness of earlier neurocomputing outputs to predicted values estimated using a counterpart multiple linear regression model is explained in detail.

  6. The maternal deprivation animal model revisited.

    PubMed

    Marco, Eva M; Llorente, Ricardo; Lpez-Gallardo, Meritxell; Mela, Virginia; Llorente-Berzal, lvaro; Prada, Carmen; Viveros, Mara-Paz

    2015-04-01

    Early life stress, in the form of MD (24h at pnd 9), interferes with brain developmental trajectories modifying both behavioral and neurobiochemical parameters. MD has been reported to enhance neuroendocrine responses to stress, to affect emotional behavior and to impair cognitive function. More recently, changes in body weight gain, metabolic parameters and immunological responding have also been described. Present data give support to the fact that neuronal degeneration and/or astrocyte proliferation are present in specific brain regions, mainly hippocampus, prefrontal cortex and hypothalamus, which are particularly vulnerable to the effects of neonatal stress. The MD animal model arises as a valuable tool for the investigation of the brain processes occurring at the narrow time window comprised between pnd 9 and 10 that are critical for the establishment of brain circuitries critical for the regulation of behavior, metabolism and energy homeostasis. In the present review we will discuss three possible mechanisms that might be crucial for the effects of MD, namely, the rapid increase in glucocorticoids, the lack of the neonatal leptin surge, and the enhanced endocannabinoid signaling during the specific critical period of MD. A better understanding of the mechanisms underlying the detrimental consequences of MD is a concern for public health and may provide new insights into mental health prevention strategies and into novel therapeutic approaches in neuropsychiatry. PMID:25616179

  7. How clonal are Neisseria species? The epidemic clonality model revisited

    PubMed Central

    Tibayrenc, Michel; Ayala, Francisco J.

    2015-01-01

    The three species Neisseria meningitidis, Neisseria gonorrheae, and Neisseria lactamica are often regarded as highly recombining bacteria. N. meningitidis has been considered a paradigmatic case of the “semiclonal model” or of “epidemic clonality,” demonstrating occasional bouts of clonal propagation in an otherwise recombining species. In this model, occasional clonality generates linkage disequilibrium in the short term. In the long run, however, the effects of clonality are countered by recombination. We show that many data are at odds with this proposal and that N. meningitidis fits the criteria that we have proposed for predominant clonal evolution (PCE). We point out that (i) the proposed way to distinguish epidemic clonality from PCE may be faulty and (ii) the evidence of deep phylogenies by microarrays and whole-genome sequencing is at odds with the predictions of the semiclonal model. Last, we revisit the species status of N. meningitidis, N. gonorrheae, and N. lactamica in the light of the PCE model. PMID:26195766

  8. Richards model revisited: validation by and application to infection dynamics.

    PubMed

    Wang, Xiang-Sheng; Wu, Jianhong; Yang, Yong

    2012-11-21

    Ever since Richards proposed his flexible growth function more than half a century ago, it has been a mystery that this empirical function has made many incredible coincidences with real ecological or epidemic data even though one of its parameters (i.e., the exponential term) does not seem to have clear biological meaning. It is therefore a natural challenge to mathematical biologists to provide an explanation of the interesting coincidences and a biological interpretation of the parameter. Here we start from a simple epidemic SIR model to revisit Richards model via an intrinsic relation between both models. Especially, we prove that the exponential term in the Richards model has a one-to-one nonlinear correspondence to the basic reproduction number of the SIR model. This one-to-one relation provides us an explicit formula in calculating the basic reproduction number. Another biological significance of our study is the observation that the peak time is approximately just a serial interval after the turning point. Moreover, we provide an explicit relation between final outbreak size, basic reproduction number and the peak epidemic size which means that we can predict the final outbreak size shortly after the peak time. Finally, we introduce a constraint in Richards model to address over fitting problem observed in the existing studies and then apply our method with constraint to conduct some validation analysis using the data of recent outbreaks of prototype infectious diseases such as Canada 2009 H1N1 outbreak, GTA 2003 SARS outbreak, Singapore 2005 dengue outbreak, and Taiwan 2003 SARS outbreak. Our new formula gives much more stable and precise estimate of model parameters and key epidemic characteristics such as the final outbreak size, the basic reproduction number, and the turning point, compared with earlier simulations without constraints. PMID:22889641

  9. Effective-Medium Models for Marine Gas Hydrates, Mallik Revisited

    NASA Astrophysics Data System (ADS)

    Terry, D. A.; Knapp, C. C.; Knapp, J. H.

    2011-12-01

    Hertz-Mindlin type effective-medium dry-rock elastic models have been commonly used for more than three decades in rock physics analysis, and recently have been applied to assessment of marine gas hydrate resources. Comparisons of several effective-medium models with derivative well-log data from the Mackenzie River Valley, Northwest Territories, Canada (i.e. Mallik 2L-38 and 5L-38) were made several years ago as part of a marine gas hydrate joint industry project in the Gulf of Mexico. The matrix/grain supporting model (one of the five models compared) was clearly a better representation of the Mallik data than the other four models (2 cemented sand models; a pore-filling model; and an inclusion model). Even though the matrix/grain supporting model was clearly better, reservations were noted that the compressional velocity of the model was higher than the compressional velocity measured via the sonic logs, and that the shear velocities showed an even greater discrepancy. Over more than thirty years, variations of Hertz-Mindlin type effective medium models have evolved for unconsolidated sediments and here, we briefly review their development. In the past few years, the perfectly smooth grain version of the Hertz-Mindlin type effective-medium model has been favored over the infinitely rough grain version compared in the Gulf of Mexico study. We revisit the data from the Mallik wells to review assertions that effective-medium models with perfectly smooth grains are a better predictor than models with infinitely rough grains. We briefly review three Hertz-Mindlin type effective-medium models, and standardize nomenclature and notation. To calibrate the extended effective-medium model in gas hydrates, we use a well accepted framework for unconsolidated sediments through Hashin-Shtrikman bounds. We implement the previously discussed effective-medium models for saturated sediments with gas hydrates and compute theoretical curves of seismic velocities versus gas hydrate saturation to compare with well log data available from the Canadian gas hydrates research site. By directly comparing the infinitely rough and perfectly smooth grain versions of the Hertz-Mindlin type effective-medium model, we provide additional insight to the discrepancies noted in the Gulf of Mexico study.

  10. Form factors of descendant operators: reduction to perturbed M (2 , 2 s + 1) models

    NASA Astrophysics Data System (ADS)

    Lashkevich, Michael; Pugai, Yaroslav

    2015-04-01

    In the framework of the algebraic approach to form factors in two-dimensional integrable models of quantum field theory we consider the reduction of the sine-Gordon model to the Φ13-perturbation of minimal conformal models of the M (2 , 2 s + 1) series. We find in an algebraic form the condition of compatibility of local operators with the reduction. We propose a construction that make it possible to obtain reduction compatible local operators in terms of screening currents. As an application we obtain exact multiparticle form factors for the compatible with the reduction conserved currents T ±2 k , Θ±(2 k-2), which correspond to the spin ±(2 k - 1) integrals of motion, for any positive integer k. Furthermore, we obtain all form factors of the operators T 2 k T -2 l , which generalize the famous operator. The construction is analytic in the s parameter and, therefore, makes sense in the sine-Gordon theory.

  11. On kaonic hydrogen. Phenomenological quantum field theoretic model revisited

    NASA Astrophysics Data System (ADS)

    Ivanov, A. N.; Cargnelli, M.; Faber, M.; Fuhrmann, H.; Ivanova, V. A.; Marton, J.; Troitskaya, N. I.; Zmeskal, J.

    2005-09-01

    We argue that due to isospin and U-spin invariance of strong low-energy interactions the S-wave scattering lengths a 0 0 and a 1 0 of N scattering with isospin I = 0 and I = 1 satisfy the low-energy theorem a 0 0 +3a 1 0 = 0 valid to leading order in chiral expansion. In the model of strong low-energy N interactions at threshold (Eur. Phys. J. A 21, 11 (2004)) we revisit the contribution of the ?(1750) resonance, which does not saturate the low-energy theorem a 0 0 +3a 1 0 = 0, and replace it by the baryon background with properties of an SU(3) octet. We calculate the S-wave scattering amplitudes of K-N and K-d scattering at threshold. We calculate the energy level displacements of the ground states of kaonic hydrogen and deuterium. The result obtained for kaonic hydrogen agrees well with recent experimental data by the DEAR Collaboration. We analyse the cross-sections for elastic and inelastic K-p scattering for laboratory momenta 70MeV/c < p K < 150MeV/c of the incident K--meson. The theoretical results agree with the available experimental data within two standard deviations.

  12. On a family of (1+1)-dimensional scalar field theory models: Kinks, stability, one-loop mass shifts

    SciTech Connect

    Alonso-Izquierdo, A.; Mateos Guilarte, J.

    2012-09-15

    In this paper we construct a one-parametric family of (1+1)-dimensional one-component scalar field theory models supporting kinks. Inspired by the sine-Gordon and {phi}{sup 4} models, we look at all possible extensions such that the kink second-order fluctuation operators are Schroedinger differential operators with Poeschl-Teller potential wells. In this situation, the associated spectral problem is solvable and therefore we shall succeed in analyzing the kink stability completely and in computing the one-loop quantum correction to the kink mass exactly. When the parameter is a natural number, the family becomes the hierarchy for which the potential wells are reflectionless, the two first levels of the hierarchy being the sine-Gordon and {phi}{sup 4} models. - Highlights: Black-Right-Pointing-Pointer We construct a family of scalar field theory models supporting kinks. Black-Right-Pointing-Pointer The second-order kink fluctuation operators involve Poeschl-Teller potential wells. Black-Right-Pointing-Pointer We compute the one-loop quantum correction to the kink mass with different methods.

  13. Revisiting the use of hyperdiffusivities in numerical dynamo models

    NASA Astrophysics Data System (ADS)

    Fournier, A.; Aubert, J.

    2012-04-01

    The groundbreaking numerical dynamo models of Glatzmaier & Roberts (1995) and Kuang & Bloxham (1997) received some criticism due to their use of hyperdiffusivities, whereby small scale processes artificially experience much stronger dissipation than large scale processes. This stronger dissipation they chose was anisotropic, in that it was only effective in the horizontal direction, and parameterized in spectral space using the following generic formula for any diffusive parameter ν ν(l) = ν0 ifl ≤ l0, ν(l) = ν0[1 + a(l- l0)n] ifl > l0, in which l is the spherical harmonic degree, ν0 is a reference value, l0 is the degree above which hyperdiffusivities start operating, and a and n are real numbers. Following the same choice as the studies mentioned above (which had most notably l0 = 0), Grote & Busse (2000) showed in a fully nonlinear context that the usage of hyperdiffusivities could lead to substantially different dynamics and magnetic field generation mechanisms. Without questioning the physical relevance of this parameterization of subgrid scale processes, we wish here to revisit the use of hyperdiffusivities (as defined mathematically above), on the account of the observation that today's models are run with a truncation at much larger spherical harmonic degree than early models. Consequently, they do not require hyperdiffusivities to kick in at the largest scales (l0 can be set to several tens). An exploration of those regions of parameter space less accessible to numerical models could therefore benefit from their use, provided they do not alter noticeably the largest scales of the dynamo (which are the ones expressing themselves in the record of the geomagnetic secular variation). We compare the statistics of a direct numerical simulation with the statistics of several hyperdiffusive simulations. In the prospect of exploring the parameter space and constructing statistics for their subsequent use for geomagnetic data assimilation practice, we conclude that a sensible use of hyperdiffusivities can lead to a much wanted decrease in computational cost, while not altering the nature of the solution.

  14. Friction versus dilation revisited: insights from theoretical and numerical models

    NASA Astrophysics Data System (ADS)

    Makedonska, N.; Sparks, D. W.; Aharonov, E.; Goren, L.

    2009-12-01

    The intimate relation between apparent friction of shearing granular layers and their dilation was already discussed by Mead in 1925. Motivated by the importance of this connection to the frictional strength of geological faults and to earthquake generation, many laboratory and numerical experiments on sheared granular layers investigated the relation between the apparent friction, ?a, and the dilation (under most situations equivalent to the change in porosity). Apparent friction is defined as the ratio of the externally-applied shear stress to the stress applied normal to the layer, measured during constant shear strain rate. Although the nature of the connection is not very well established, ?a is often cited to be the sum of two contributions: 1. The surface friction coefficient, ?s, of the grains and 2. The dilation rate. The contribution of the dilation rate to ?a arises since dilation is required to allow grain rearrangement during shear, yet dilation requires input of work against the normal stress. We revisit the connection between apparent friction and dilation using theoretical treatment of two-dimensional sheared uniform granular layers and complementary Discrete Element simulations, both for gouge layers and for a rough surface without gouge. Our theoretical calculation shows that fluctuations in both ?a and dilation rate that occur during a particular type grain-scale shear motion follow a relationship that is non-linear, although in practice appears close to linear. Results show that dilation (and hence ?a) is connected to shear localization. In numerical simulations of mono-sized gouge layers (without grain breaking or chemical processes) shear localization occurs but does not persist; instead the systems fluctuate between a state of distributed shear and dilation and a localized motion on short-lived shear planes, with overall compaction. The transition between these two types of shear involves a large change in dilation rate, and leads to large deviations from the sublinear friction-dilation rate relationship. Models with non-uniform grains also show significant scatter about the linear relationship, and we attribute this to short-lived temporal and spatial variations in the extent of shear localization. We discuss the physical origin of these fluctuations.

  15. Revisiting the model predicting maximal 2-3 mixing and CP violation for neutrinos

    NASA Astrophysics Data System (ADS)

    Takasugi, Eiichi

    2015-11-01

    The model of the neutrino mass matrix that we proposed in 2000 is revisited in the light of the recent T2K experiments. This model has the special property that it predicts maximal 2-3 mixing and CP violation under some simple condition. In this model, if the condition is relaxed, the 2-3 angle and the CP violation deviate from their maximal values and are related. We present such relations for typical cases.

  16. ODE/IM correspondence for the Fateev model

    NASA Astrophysics Data System (ADS)

    Lukyanov, Sergei L.

    2013-12-01

    The Fateev model is somewhat special among two-dimensional quantum field theories. For different values of the parameters, it can be reduced to a variety of integrable systems. An incomplete list of the reductions includes O(3) and O(4) non-linear sigma models and their continuous deformations (2D and 3D sausages, anisotropic principal chiral field), the Bukhvostov-Lipatov model, the N = 2 supersymmetric sine-Gordon model, as well as the integrable perturbed SU 2( n) ⊗ SU 2( p - 2) /SU 2( n + p - 2) coset CFT. The model possesses a mysterious symmetry structure of the exceptional quantum superalgebras U q ((2|1; α)). In this work, we propose the ODE/IM correspondence between the Fateev model and a certain generalization of the classical problem of constant mean curvature embedding of a thrice-punctured sphere in AdS 3.

  17. Slowly modulated baroclinic waves in a three-layer model

    NASA Astrophysics Data System (ADS)

    Moroz, I. M.

    1981-03-01

    A coupled pair of envelope equations is derived which describe the nonlinear evolution of slowly varying wave packets in a three-layer model of baroclinic instability on a beta-plane. The equations are identical in form to those obtained by Pedlosky (1972) to study wave-packet evolution in a two-layer model. They are transformable to the self-induced transparency equations of nonlinear optics for complex wave amplitude, and to the sine-Gordon equation for real wave amplitude. Both are known to possess soliton solutions, with associated highly predictable behavior. The three-layer model therefore is another example of a mathematical model of baroclinic instability to exhibit soliton behavior. The significance of such solutions to meteorology and oceanography is discussed.

  18. Revisiting the Mode-Beating Model of AC Helicity Injection

    NASA Astrophysics Data System (ADS)

    Sauppe, J. P.; Sovinec, C. R.

    2010-11-01

    Oscillating field current drive (OFCD), or AC helicity injection, is an important candidate for current sustainment in reversed-field pinch devices. Bellan examined AC helicity injection in a slab geometry and described it as a beating between two plasma modes that produces a mean current parallel to the equilibrium magnetic field [P. M. Bellan. Phys. Rev. Lett. 54, 1381 (1985)]. This mean current is confined to within a classical resistive skin depth of the plasma surface, and plasma relaxation is responsible for transporting this current to the core. We revisit this analytical work and examine how this wave-beating effect is represented in zero-beta MHD simulations, including consideration of the choice of boundary conditions. In addition to the expected parallel current, numerical simulations show a pinch effect from a cycle-averaged current that is perpendicular to the mean magnetic field, which is not described in Bellan's original work. Our results are discussed with respect to Boozer's general anti-dynamo theorem [A. H. Boozer. Phys. Fluids B Vol. 5, 2271 (1993)].

  19. Differential equations and integrable models: the /SU(3) case

    NASA Astrophysics Data System (ADS)

    Dorey, Patrick; Tateo, Roberto

    2000-04-01

    We exhibit a relationship between the massless a2(2) integrable quantum field theory and a certain third-order ordinary differential equation, thereby extending a recent result connecting the massless sine-Gordon model to the Schrdinger equation. This forms part of a more general correspondence involving A2-related Bethe ansatz systems and third-order differential equations. A non-linear integral equation for the generalised spectral problem is derived, and some numerical checks are performed. Duality properties are discussed, and a simple variant of the non-linear equation is suggested as a candidate to describe the finite volume ground state energies of minimal conformal field theories perturbed by the operators ?12, ?21 and ?15. This is checked against previous results obtained using the thermodynamic Bethe ansatz.

  20. Interaction of Three Waves for the Extension (2+1)-Dimensional Sine-Gordon Equation

    NASA Astrophysics Data System (ADS)

    Chen, Wei; Chen, Han-Lin; Dai, Zheng-De

    2014-11-01

    Exact solutions with three-wave form including three solitary wave, breather-type two-solitary wave, doubly breather-type of solitary wave, double-periodic kind of solitary wave are obtained using bilinear form and extended three-wave approach with the aid of Maple. It is important that completed elastic collision, non-completed elastic collision, and fusion of three waves are investigated, respectively.

  1. Nonlinear integral equations for complex affine Toda models associated with simply laced Lie algebras

    NASA Astrophysics Data System (ADS)

    Zinn-Justin, P.

    1998-08-01

    A set of coupled nonlinear integral equations (NLIE) is derived for a class of models connected to the quantum group 0305-4470/31/31/019/img1 (0305-4470/31/31/019/img2 simply laced Lie algebra), which are solvable using the Bethe ansatz; these equations describe arbitrary excited states of a system with finite spatial length L. They generalize the simpler NLIE of the sine-Gordon/massive Thirring model to affine Toda field theory with imaginary coupling constant. As an application, the central charge and all the conformal weights of the UV conformal field theory are extracted in a straightforward manner. The quantum group truncation for q at a root of unity is discussed in detail; in the UV limit we recover through this procedure the RCFTs with extended 0305-4470/31/31/019/img3 conformal symmetry.

  2. Revisiting the Boundary Layer Leaf Water Isotopic Model

    NASA Astrophysics Data System (ADS)

    Feng, X.; Shu, Y.; Posmentier, E. S.; Sonder, L. J.; Yakir, D.

    2007-12-01

    The boundary layer (BL) model for oxygen or hydrogen isotopic composition of leaf water has been widely used in the past four decades, and has been incorporated into models that require information about leaf water isotopic variations. However, since its introduction, model predictions of the bulk leaf water have often exceeded observed isotopic enrichments. There are also cases in which the model yielded lower than observed isotopic enrichments of bulk leaf water. In general, underpredictions occur under relatively high humidity. In order to explain why the BL model overpredicts the isotopic composition, several modifications of the model have been proposed. However, no explanation exists for why the BL model underestimates observed isotopic enrichments. We recently developed a 2D model that successfully simulates the observed along-leaf 18O enrichment of pine needles, and can explain why the BL model could have over- or under-predicted the bulk leaf water ?18O values. In the BL model, bulk leaf water is isotopically equivalent to water at the evaporation site, fed directly by stem water. In a real leaf, however, stem water enters the base of the leaf and becomes progressively enriched in 18O towards the tip due to fractionation by transpiration, consistent with both our observations and behavior of the 2D model. Therefore, at least part of the leaf water, that near the base, would have isotopic values lower than water at transpiration sites predicted by the BL model, which might thus overestimate bulk isotope values. On the other hand, as water moves through a leaf, it becomes increasingly enriched in 18O, and the leaf water near the tip may have ?18O values well above the BL model prediction. Therefore, it is also possible for the BL model to underestimate the bulk leaf water ?18O. The actual isotopic composition of the bulk leaf water is a combination of these two effects. It is clear then that the BL model may not accurately predict the ?18O value of the bulk leaf water, because to do so would require the volumetric average of the ?18O in the depleted and enriched parts of the leaf to exactly equal the BL model prediction. Furthermore, if leaves are assumed to transpire fast under low humidity, our 2D model can also reproduce the humidity dependence of the discrepancy between observation and the BL model prediction. This suggests an interaction between environmental conditions and the physiological behavior of plants. If the simplicity of the BL model justifies its continued use, then it is important to investigate its accuracy further under different environmental conditions and for leaves with different morphologies and water transport pathways.

  3. Revisiting "Discrepancy Analysis in Continuing Medical Education: A Conceptual Model"

    ERIC Educational Resources Information Center

    Fox, Robert D.

    2011-01-01

    Based upon a review and analysis of selected literature, the author presents a conceptual model of discrepancy analysis evaluation for planning, implementing, and assessing the impact of continuing medical education (CME). The model is described in terms of its value as a means of diagnosing errors in the development and implementation of CME. The

  4. Revisiting the domain model for lithium intercalated graphite

    SciTech Connect

    Krishnan, Sridevi; Brenet, Gilles; Caliste, Damien; Genovese, Luigi; Deutsch, Thierry; Pochet, Pascal

    2013-12-16

    In this Letter, we study the stability of the domain model for lithium intercalated graphite in stages III and II by means of Density Functional Theory and Kinetic Lattice Monte Carlo simulations. We find that the domain model is either thermodynamically or kinetically stable when compared to the standard model in stages III and II. The existence of domains in the intercalation sequence is well supported by recent high resolution transmission electron microscope observations in lithiated graphite. Moreover, we predict that such domain staging sequences leads to a wide range of diffusivity as reported in experiments.

  5. Running of radiative neutrino masses: the scotogenic model revisited

    NASA Astrophysics Data System (ADS)

    Merle, Alexander; Platscher, Moritz

    2015-11-01

    A few years ago, it had been shown that effects stemming from renormalisation group running can be quite large in the scotogenic model, where neutrinos obtain their mass only via a 1-loop diagram (or, more generally, in many models in which the light neutrino mass is generated via quantum corrections at loop-level). We present a new computation of the renormalisation group equations (RGEs) for the scotogenic model, thereby updating previous results. We discuss the matching in detail, in particular in what regards the different mass spectra possible for the new particles involved. We furthermore develop approximate analytical solutions to the RGEs for an extensive list of illustrative cases, covering all general tendencies that can appear in the model. Comparing them with fully numerical solutions, we give a comprehensive discussion of the running in the scotogenic model. Our approach is mainly top-down, but we also discuss an attempt to get information on the values of the fundamental parameters when inputting the low-energy measured quantities in a bottom-up manner. This work serves the basis for a full parameter scan of the model, thereby relating its low- and high-energy phenomenology, to fully exploit the available information.

  6. Zwislocki's model of the middle ear re-visited

    NASA Astrophysics Data System (ADS)

    Withnell, Robert H.; Fields, Taylor N.

    2015-12-01

    Zwislocki's circuit model of the middle ear [11] has been used, in original or modified form, in subsequent studies modeling the ear [4, 6]. The model includes two eardrum modes of vibration, a shunt for flexible coupling between the incus and stapes, and a single tuned oscillator for ossicular vibration. The contribution of each of these mechanisms was examined by fitting a model of the ear to acoustic input impedance data from healthy human ears. The circuit elements for a non-ossicular eardrum vibration and a flexible coupling between the incus and stapes were found to be detrimental or non-essential for the model-fit-to-data. A single mode of eardrum vibration for sound transmission to the middle ear is consistent with the eardrum acting as an impedance-matching device, with pars-tensa eardrum vibration coupled to the ossicles [1]. A single-tuned oscillator was insufficient to account for the bandwidth of the ear. The frequency response of the ear suggests multiple resonant modes of ossicular vibration.

  7. The Dualistic Model of Ovarian Carcinogenesis: Revisited, Revised, and Expanded.

    PubMed

    Kurman, Robert J; Shih, Ie-Ming

    2016-04-01

    Since our proposal of a dualistic model of epithelial ovarian carcinogenesis more than a decade ago, a large number of molecular and histopathologic studies were published that have provided important insights into the origin and molecular pathogenesis of this disease. This has required that the original model be revised and expanded to incorporate these findings. The new model divides type I tumors into three groups: i) endometriosis-related tumors that include endometrioid, clear cell, and seromucinous carcinomas; ii) low-grade serous carcinomas; and iii) mucinous carcinomas and malignant Brenner tumors. As in the previous model, type II tumors are composed, for the most part, of high-grade serous carcinomas that can be further subdivided into morphologic and molecular subtypes. Type I tumors develop from benign extraovarian lesions that implant on the ovary and which can subsequently undergo malignant transformation, whereas many type II carcinomas develop from intraepithelial carcinomas in the fallopian tube and, as a result, disseminate as carcinomas that involve the ovary and extraovarian sites, which probably accounts for their clinically aggressive behavior. The new molecular genetic data, especially those derived from next-generation sequencing, further underline the heterogeneity of ovarian cancer and identify actionable mutations. The dualistic model highlights these differences between type I and type II tumors which, it can be argued, describe entirely different groups of diseases. PMID:27012190

  8. The hydrogeologic-geochemical model of Cerro Prieto revisited

    SciTech Connect

    Lippmann, M.J.; Halfman, S.E.; Truesdell, A.H.; Manon M., A.

    1989-01-01

    As the exploitation of the Cerro Prieto, Mexico, geothermal field continues, there is increasing evidence that the hydrogeologic model developed by Halfman et al. (1984, 1986) presents the basic features controlling the movement of geothermal fluids in the system. At the present time the total installed capacity at Cerro Prieto is 620 MWe requiring the production of more than 10,500 tonnes/hr of a brine-steam mixture. This significant rate of fluid production has resulted in changes in reservoir thermodynamic conditions and in the chemistry of the produced fluids. After reviewing the hydrogeologic-geochemical model of Cerro Prieto, some of the changes observed in the field due to its exploitation are discussed and interpreted on the basis of the model. 21 refs., 11 figs., 1 tab.

  9. Energy-economy interactions revisited within a comprehensive sectoral model

    SciTech Connect

    Hanson, D. A.; Laitner, J. A.

    2000-07-24

    This paper describes a computable general equilibrium (CGE) model with considerable sector and technology detail, the ``All Modular Industry Growth Assessment'' Model (AMIGA). It is argued that a detailed model is important to capture and understand the several rolls that energy plays within the economy. Fundamental consumer and industrial demands are for the services from energy; hence, energy demand is a derived demand based on the need for heating, cooling mechanical, electrical, and transportation services. Technologies that provide energy-services more efficiently (on a life cycle basis), when adopted, result in increased future output of the economy and higher paths of household consumption. The AMIGA model can examine the effects on energy use and economic output of increases in energy prices (e.g., a carbon charge) and other incentive-based policies or energy-efficiency programs. Energy sectors and sub-sector activities included in the model involve energy extraction conversion and transportation. There are business opportunities to produce energy-efficient goods (i.e., appliances, control systems, buildings, automobiles, clean electricity). These activities are represented in the model by characterizing their likely production processes (e.g., lighter weight motor vehicles). Also, multiple industrial processes can produce the same output but with different technologies and inputs. Secondary recovery, i.e., recycling processes, are examples of these multiple processes. Combined heat and power (CHP) is also represented for energy-intensive industries. Other modules represent residential and commercial building technologies to supply energy services. All sectors of the economy command real resources (capital services and labor).

  10. The Thirring-Wess model revisited: a functional integral approach

    SciTech Connect

    Belvedere, L.V. . E-mail: armflavio@if.uff.br

    2005-06-01

    We consider the Wess-Zumino-Witten theory to obtain the functional integral bosonization of the Thirring-Wess model with an arbitrary regularization parameter. Proceeding a systematic of decomposing the Bose field algebra into gauge-invariant- and gauge-non-invariant field subalgebras, we obtain the local decoupled quantum action. The generalized operator solutions for the equations of motion are reconstructed from the functional integral formalism. The isomorphism between the QED {sub 2} (QCD {sub 2}) with broken gauge symmetry by a regularization prescription and the Abelian (non-Abelian) Thirring-Wess model with a fixed bare mass for the meson field is established.

  11. What drives health care expenditure?--Baumol's model of 'unbalanced growth' revisited.

    PubMed

    Hartwig, Jochen

    2008-05-01

    The share of health care expenditure in GDP rises rapidly in virtually all OECD countries, causing increasing concern among politicians and the general public. Yet, economists have to date failed to reach an agreement on what the main determinants of this development are. This paper revisits Baumol's [Baumol, W.J., 1967. Macroeconomics of unbalanced growth: the anatomy of urban crisis. American Economic Review 57 (3), 415-426] model of 'unbalanced growth', showing that the latter offers a ready explanation for the observed inexorable rise in health care expenditure. The main implication of Baumol's model in this context is that health care expenditure is driven by wage increases in excess of productivity growth. This hypothesis is tested empirically using data from a panel of 19 OECD countries. Our tests yield robust evidence in favor of Baumol's theory. PMID:18164773

  12. Revisiting competition in a classic model system using formal links between theory and data.

    PubMed

    Hart, Simon P; Burgin, Jacqueline R; Marshall, Dustin J

    2012-09-01

    Formal links between theory and data are a critical goal for ecology. However, while our current understanding of competition provides the foundation for solving many derived ecological problems, this understanding is fractured because competition theory and data are rarely unified. Conclusions from seminal studies in space-limited benthic marine systems, in particular, have been very influential for our general understanding of competition, but rely on traditional empirical methods with limited inferential power and compatibility with theory. Here we explicitly link mathematical theory with experimental field data to provide a more sophisticated understanding of competition in this classic model system. In contrast to predictions from conceptual models, our estimates of competition coefficients show that a dominant space competitor can be equally affected by interspecific competition with a poor competitor (traditionally defined) as it is by intraspecific competition. More generally, the often-invoked competitive hierarchies and intransitivities in this system might be usefully revisited using more sophisticated empirical and analytical approaches. PMID:23094373

  13. MRAC Revisited: Guaranteed Performance with Reference Model Modification

    NASA Technical Reports Server (NTRS)

    Stepanyan, Vahram; Krishnakumar, Kalmaje

    2010-01-01

    This paper presents modification of the conventional model reference adaptive control (MRAC) architecture in order to achieve guaranteed transient performance both in the output and input signals of an uncertain system. The proposed modification is based on the tracking error feedback to the reference model. It is shown that approach guarantees tracking of a given command and the ideal control signal (one that would be designed if the system were known) not only asymptotically but also in transient by a proper selection of the error feedback gain. The method prevents generation of high frequency oscillations that are unavoidable in conventional MRAC systems for large adaptation rates. The provided design guideline makes it possible to track a reference command of any magnitude form any initial position without re-tuning. The benefits of the method are demonstrated in simulations.

  14. Laws of reflection and Snell's law revisited by video modeling

    NASA Astrophysics Data System (ADS)

    Rodrigues, M.; Simeo Carvalho, P.

    2014-07-01

    Video modelling is being used, nowadays, as a tool for teaching and learning several topics in Physics. Most of these topics are related to kinematics. In this work we show how video modelling can be used for demonstrations and experimental teaching in optics, namely the laws of reflection and the well-known Snell's Law of light. Videos were recorded with a photo camera at 30 frames/s, and analysed with the open source software Tracker. Data collected from several frames was treated with the Data Tool module, and graphs were built to obtain relations between incident, reflected and refraction angles, as well as to determine the refractive index of Perspex. These videos can be freely distributed in the web and explored with students within the classroom, or as a homework assignment to improve student's understanding on specific contents. They present a large didactic potential for teaching basic optics in high school with an interactive methodology.

  15. NEW SOLAR COMPOSITION: THE PROBLEM WITH SOLAR MODELS REVISITED

    SciTech Connect

    Serenelli, Aldo M.; Asplund, Martin; Basu, Sarbani; Ferguson, Jason W.

    2009-11-10

    We construct updated solar models with different sets of solar abundances, including the most recent determinations by Asplund et al. The latter work predicts a larger (approx10%) solar metallicity compared to previous measurements by the same authors but significantly lower (approx25%) than the recommended value from a decade ago by Grevesse and Sauval. We compare the results of our models with determinations of the solar structure inferred through helioseismology measurements. The model that uses the most recent solar abundance determinations predicts the base of the solar convective envelope to be located at R {sub CZ} = 0.724 R{sub sun} and a surface helium mass fraction of Y{sub surf} = 0.231. These results are in conflict with helioseismology data (R{sub CZ} = 0.713 +- 0.001 R{sub sun} and Y{sub surf} = 0.2485 +- 0.0035) at 5sigma and 11sigma levels, respectively. Using the new solar abundances, we calculate the magnitude by which radiative opacities should be modified in order to restore agreement with helioseismology. We find that a maximum change of approx15% at the base of the convective zone is required with a smooth decrease toward the core, where the change needed is approx5%. The required change at the base of the convective envelope is about half the value estimated previously. We also present the solar neutrino fluxes predicted by the new models. The most important changes brought about by the new solar abundances are the increase by approx10% in the predicted {sup 13}N and {sup 15}O fluxes that arise mostly due to the increase in the C and N abundances in the newly determined solar composition.

  16. A revisit to the one form kinetic model of prothrombinase.

    PubMed

    Lee, Chang Jun; Wu, Sangwook; Eun, Changsun; Pedersen, Lee G

    2010-06-01

    Thrombin is generated enzymatically from prothrombin by two pathways with the intermediates of meizothrombin and prethrombin-2. Experimental concentration profiles from two independent groups for these two pathways have been re-analyzed. By rationally combining the independent data sets, a simple mechanism can be established and rate constants determined. A structural model is consistent with the data-derived finding that mechanisms that feature channeling or ratcheting are not necessary to describe thrombin production. PMID:20435402

  17. The comfortable driving model revisited: traffic phases and phase transitions

    NASA Astrophysics Data System (ADS)

    Knorr, Florian; Schreckenberg, Michael

    2013-07-01

    We study the spatiotemporal patterns resulting from different boundary conditions for a microscopic traffic model and contrast them with empirical results. By evaluating the time series of local measurements, the local traffic states are assigned to the different traffic phases of Kerners three-phase traffic theory. For this classification we use the rule-based FOTO-method, which provides hard rules for this assignment. Using this approach, our analysis shows that the model is indeed able to reproduce three qualitatively different traffic phases: free flow (F), synchronized traffic (S), and wide moving jams (J). In addition, we investigate the likelihood of transitions between the three traffic phases. We show that a transition from free flow to a wide moving jam often involves an intermediate transition: first from free flow to synchronized flow and then from synchronized flow to a wide moving jam. This is supported by the fact that the so-called F ? S transition (from free flow to synchronized traffic) is much more likely than a direct F ? J transition. The model under consideration has a functional relationship between traffic flow and traffic density. The fundamental hypothesis of the three-phase traffic theory, however, postulates that the steady states of synchronized flow occupy a two-dimensional region in the flow-density plane. Due to the obvious discrepancy between the model investigated here and the postulate of the three-phase traffic theory, the good agreement that we found could not be expected. For a more detailed analysis, we also studied vehicle dynamics at a microscopic level and provide a comparison of real detector data with simulated data of the identical highway segment.

  18. Casimir force in noncommutative Randall-Sundrum models revisited

    SciTech Connect

    Teo, L. P.

    2010-07-15

    We propose another method to compute the Casimir force in noncommutative Randall-Sundrum braneworld model considered by K. Nouicer and Y. Sabri, Phys. Rev. D 80, 086013 (2009). recently. Our method can be used to compute the Casimir force to any order in the noncommutative parameter. Contrary to the claim made by K. Nouicer and Y. Sabri that repulsive Casimir force can appear in the first order approximation, we show that the Casimir force is always attractive at any order of approximation.

  19. Allele frequencies at microsatellite loci: The stepwise mutation model revisited

    SciTech Connect

    Valdes, A.M.; Slatkin, M. ); Freimer, N.B. )

    1993-03-01

    The authors summarize available data on the frequencies of alleles at microsatellite loci in human populations and compare observed distributions of allele frequencies to those generated by a simulation of the stepwise mutation model. They show that observed frequency distributions at 108 loci are consistent with the results of the model under the assumption that mutations cause an increase or decrease in repeat number by one and under the condition that the product Nu, where N is the effective population size and u is the mutation rate, is larger than one. It is also shown that the variance of the distribution of allele sizes is a useful estimator of Nu and performs much better than previously suggested estimators for the stepwise mutation model. In the data, there is no correlation between the mean and variance in allele size at a locus or between the number of alleles and mean allele size, which suggests that the mutation rate at these loci is independent of allele size. 39 refs., 6 figs., 4 tabs.

  20. The Distributed D-Clean Model Revisited by Templates

    NASA Astrophysics Data System (ADS)

    Zsk, Viktria; Porkolb, Zoltn

    2011-09-01

    D-Clean is a functional coordination language for distributed computation. The language was designed for the need of high-level process description and communication coordination of functional programs distributed over a cluster. The pure functional computational nodes required language primitives to control the dataflow in a distributed process-network. Therefore, in order to achieve parallel features, we created an extension for the lazy functional programming language Clean using new language elements. D-Clean is compiled to an intermediate level language called D-Box, which is designed for the description of the computational nodes. Every D-Clean construct generates a D-Box expression. The D-Box expressions hide the low level implementation details and enable direct control over the process-network. The asynchronous communication is based on language-independent middleware services. Earlier we have presented the syntax and the semantics of both coordination languages. Practical experiences showed the difficulties of distributed program development, especially in testing and debugging. This paper aims to provide software comprehension application for a better understanding and usage of the D-Clean distributed system. We model the elements and the behaviour of the D-Clean system using C++ templates. The strong type system of C++ templates guarantees the correctness of the model. Using templates we can avoid run-time overhead achieving impressive efficiency.

  1. The Zipf Law revisited: An evolutionary model of emerging classification

    SciTech Connect

    Levitin, L.B.; Schapiro, B.; Perlovsky, L.

    1996-12-31

    Zipf`s Law is a remarkable rank-frequency relationship observed in linguistics (the frequencies of the use of words are approximately inversely proportional to their ranks in the decreasing frequency order) as well as in the behavior of many complex systems of surprisingly different nature. We suggest an evolutionary model of emerging classification of objects into classes corresponding to concepts and denoted by words. The evolution of the system is derived from two basic assumptions: first, the probability to recognize an object as belonging to a known class is proportional to the number of objects in this class already recognized, and, second, there exists a small probability to observe an object that requires creation of a new class ({open_quotes}mutation{close_quotes} that gives birth to a new {open_quotes}species{close_quotes}). It is shown that the populations of classes in such a system obey the Zipf Law provided that the rate of emergence of new classes is small. The model leads also to the emergence of a second-tier structure of {open_quotes}super-classes{close_quotes} - groups of classes with almost equal populations.

  2. Tail Lobe Revisited: Magnetic Field Modeling Based on Plasma Data

    NASA Technical Reports Server (NTRS)

    Karlsson, S. B. P.; Tsyganenko, N. A.

    1999-01-01

    Plasma data from the ISEE-1 and -2 spacecraft during 1977-1980 have been used to determine the distribution of data points in the magnetotail in the range of distances -20 < XGSM < --15, i.e. which of the records that were located in the current sheet, in the tail lobe, in the magnetosheath and in the boundary layers respectively. The ISEE-1 and -2 magnetic field data for the records in the tail lobe were then used to model the tail lobe magnetic field dependence on the solar wind dynamic pressure, on the Interplanetary Magnetic Field (IMF) and on the Dst index. The tail lobe magnetic field was assumed to be dependent on the square root of the dynamic pressure based on the balance between the total magnetic pressure in the tail lobes and the dynamic pressure of the solar wind. The IMF dependent terms, added to the pressure term, were sought in many different forms while the Dst dependence of the tail lobe magnetic field was assumed to be linear. The field shows a strong dependence on the square root of the dynamic pressure and the different IMF dependent terms all constitute a significant contribution to the total field. However, the dependence on the Dst index turned out to be very weak at those down-tail distances. The results of this study are intended to be used for parameterizing future versions of the data-based models of the global magnetospheric magnetic field.

  3. Murray's law revisited: Qumada's fluid model and fractal trees

    NASA Astrophysics Data System (ADS)

    Moreau, Baptiste; Mauroy, Benjamin

    2015-11-01

    In 1926, Murray proposed the first law for the optimal design of blood vessels. He minimized the power dissipation arising from the trade-off between fluid circulation and blood maintenance. The law, based on a constant fluid viscosity, states that in the optimal configuration the fluid flow rate inside the vessel is proportional to the cube of the vessel radius, implying that wall shear stress is not dependent on the vessel radius. Murray's law has been found to be true in blood macrocirculation, but not in microcirculation. In 2005, Alarc\\'on et al took into account the non monotonous dependence of viscosity on vessel radius - F{\\aa}hr{\\ae}us-Lindqvist effect - due to phase separation effect of blood. They were able to predict correctly the behavior of wall shear stresses in microcirculation. One last crucial step remains however: to account for the dependence of blood viscosity on shear rates. In this work, we investigate how viscosity dependence on shear rate affects Murray's law. We extended Murray's optimal design to the whole range of Qu\\'emada's fluids, that models pseudo-plastic fluids such as blood. Our study shows that Murray's original law is not restricted to Newtonian fluids, it is actually universal for all Qu\\'emada's fluid as long as there is no phase separation effect. When phase separation effect occurs, then we derive an extended version of Murray's law. Our analyses are very general and apply to most of fluids with shear dependent rheology. Finally, we study how these extended laws affect the optimal geometries of fractal trees to mimic an idealized arterial network.

  4. Yukawa Meson, Sakata Model and Baryon-Lepton Symmetry Revisited

    NASA Astrophysics Data System (ADS)

    Marshak, R. E.

    It is difficult for me to grasp that this symposium is celebrating the jubilee of meson theory since I was a junior at Columbia College in 1935. I recall hearing a colloquium by Paul Dirac that year telling an enraptured audience about the infinite sea of negative energy states but I do not recall any special note being taken of the birth of an equally revolutionary concept, the Yukawa meson. Perhaps the reason was the publication of Hideki Yukawa's paper in an inaccessible Japanese journal, perhaps Dirac's electron theory was dealing with the well-known electromagnetic force whereas Yukawa' meson theory was put forth to understand the nature of two new forces - the nuclear and the weak. Whatever the reason, the situation changed drastically when I migrated to Cornell (to do my thesis under Hans Bethe during the years 1937sim39) and found a deep interest in meson theory. Thus, my own scientific career has almost spanned the period since the birth of meson theory but, what is more to the point, it has been strongly influenced by the work of Yukawa and his collaborators. It therefore gives me great pleasure to be able to talk at this MESON 50 symposium. As one of the oldest speakers, I shall respond in a loose way to Professor Maki's invitation to cover ``topics concerning the historical developments of hadron physics''. I shall select several major themes from the Japanese work that have had special interest for me. My remarks will fall under the four headings: (A) Yukawa Meson; (B) Sakata Model; (C) Baryon-Lepton Symmetry; and (D) Extensions of Baryon-Lepton Symmetry.

  5. Revisiting food-based models of territoriality in solitary predators.

    PubMed

    Lpez-Bao, Jos V; Rodrguez, Alejandro; Delibes, Miguel; Fedriani, Jos M; Calzada, Javier; Ferreras, Pablo; Palomares, Francisco

    2014-07-01

    Food availability is considered a major factor determining spacing behaviour in territorial species, especially for females. Theoretically, spatial overlap (considered the opposite of territoriality) and food availability are related in a nonlinear manner (hypothesized inverted-U function), with high overlap levels at the extremes of a food availability gradient and low overlap at intermediate levels of this gradient. Similar patterns are expected for encounter frequencies owing to its expected correlation with spatial overlap. However, these predictions have rarely been tested in highly structured social systems on a broad gradient of food availability, which implicitly requires experimental manipulation. We test these predictions in a solitary, territorial and trophic specialist, the Iberian lynx Lynx pardinus, taking advantage of a three-decade data set of spatial behaviour in different scenarios of food availability (i.e. rabbit density). In contrast with expectations, home range overlap among resident females was low (median overlap index = 0.08, range 0-0.57) and core area overlap was nearly nil (median overlap index = 0, range 0-0.22) throughout the entire gradient of prey availability. Furthermore, spatial associations between pairs of females were negligible regardless marked variation in prey availability. Therefore, we did not find support for a model of flexible lynx territoriality driven by food availability. Our results suggest that the exclusive use of space in the Iberian lynx was not related to food. Lack of influence of prey availability on lynx territoriality may be adaptive to cope with the consequences of frequent drought-induced periods of prey scarcity or other disturbance typically affecting wild rabbit populations in Mediterranean environments. Thus, lynx would adopt an obstinate strategy of territoriality that consists in defending exclusive areas across a broad range of resource availability ensuring an exclusive access to the minimum amount of prey necessary for survival and eventually reproduction even during periods of prey scarcity. However, we found signs that territoriality was influenced by lynx density in a nonlinear fashion. Our results suggest the occurrence of population regulation through territoriality in this species. PMID:24720673

  6. The Eating Attitudes Test-26 revisited using exploratory structural equation modeling.

    PubMed

    Maïano, Christophe; Morin, Alexandre J S; Lanfranchi, Marie-Christine; Therme, Pierre

    2013-07-01

    Most previous studies have failed to replicate the original factor structure of the 26-item version of the Eating Attitudes Test (EAT-26) among community samples of adolescents. The main objective of the present series of four studies (n = 2178) was to revisit the factor structure of this instrument among mixed gender community samples of adolescents using both exploratory structural equation modeling (ESEM) and confirmatory factor analysis (CFA). First, results from the ESEM analyses provided satisfactory goodness-of-fit statistics and reliability coefficients for a six-factor model of the EAT with 18 items (EAT-18) closely corresponding to the original seven-factor structure proposed for the 40-item version of the EAT. Second, these analyses were satisfactorily replicated among a new sample of community adolescents using CFA. The results confirmed the factor loading and intercept invariance of this model across gender and age groups (i.e., early and late adolescence), as well as the complete invariance of the EAT-18 measurement model between ethnicities (i.e., European versus African origins) and across weight categories (i.e., underweight, normal weight and overweight). Finally, the last study provided support for convergent validity of the EAT-18 with the Eating Disorder Inventory and with instruments measuring global self-esteem, physical appearance, social physique anxiety and fear of negative appearance evaluation. PMID:23344702

  7. Modelling crystal plasticity by 3D dislocation dynamics and the finite element method: The Discrete-Continuous Model revisited

    NASA Astrophysics Data System (ADS)

    Vattr, A.; Devincre, B.; Feyel, F.; Gatti, R.; Groh, S.; Jamond, O.; Roos, A.

    2014-02-01

    A unified model coupling 3D dislocation dynamics (DD) simulations with the finite element (FE) method is revisited. The so-called Discrete-Continuous Model (DCM) aims to predict plastic flow at the (sub-)micron length scale of materials with complex boundary conditions. The evolution of the dislocation microstructure and the short-range dislocation-dislocation interactions are calculated with a DD code. The long-range mechanical fields due to the dislocations are calculated by a FE code, taking into account the boundary conditions. The coupling procedure is based on eigenstrain theory, and the precise manner in which the plastic slip, i.e. the dislocation glide as calculated by the DD code, is transferred to the integration points of the FE mesh is described in full detail. Several test cases are presented, and the DCM is applied to plastic flow in a single-crystal Nickel-based superalloy.

  8. Revisiting the Slichter mode of Mercury in the context of differentiated models

    NASA Astrophysics Data System (ADS)

    Escapa, A.; Fukushima, T.

    2015-11-01

    We revisit the Slichter mode of a set of differentiated Mercury models that were considered previously. We apply a different and independent formalism, based on variational principles of mechanics, to analytically model the internal translations of a body with a global internal perfect fluid layer limited by two differentiated rigid solid constituents that have a spherical symmetric mass distribution. The Slichter mode is specified by providing the time evolution of the barycenters of the solid constituents, the amplitude ratio of the mantle to the inner core, and the period of the oscillatory motion. All these parameters only depend on the mass of the body, the mass of the inner core, the density of the fluid, and the mean density of the inner core. For previously developed Mercury models we find, in contrast to other results, that there are no discontinuities in the Slichter period when passing from undifferentiated to differentiated inner cores. Hence, in a general situation, a potential detection of the Slichter mode cannot determine the differentiation of the inner core. We also find that the BepiColombo mission may be able to detect the Slichter mode caused by an impactor meteroid with a mass of about 1012 kg in the most favorable of circumstances. This shows that a measurable excitation of the mode by this mechanism is even more unlikely than was previously established, where a mass about 1010 kg was found. Appendices are available in electronic form at http://www.aanda.org

  9. Revisited reaction-diffusion model of thermal desorption spectroscopy experiments on hydrogen retention in material

    NASA Astrophysics Data System (ADS)

    Guterl, Jerome; Smirnov, R. D.; Krasheninnikov, S. I.

    2015-07-01

    Desorption phase of thermal desorption spectroscopy (TDS) experiments performed on tungsten samples exposed to flux of hydrogen isotopes in fusion relevant conditions is analyzed using a reaction-diffusion model describing hydrogen retention in material bulk. Two regimes of hydrogen desorption are identified depending on whether hydrogen trapping rate is faster than hydrogen diffusion rate in material during TDS experiments. In both regimes, a majority of hydrogen released from material defects is immediately outgassed instead of diffusing deeply in material bulk when the evolution of hydrogen concentration in material is quasi-static, which is the case during TDS experiments performed with tungsten samples exposed to flux of hydrogen isotopes in fusion related conditions. In this context, analytical expressions of the hydrogen outgassing flux as a function of the material temperature are obtained with sufficient accuracy to describe main features of thermal desorption spectra (TDSP). These expressions are then used to highlight how characteristic temperatures of TDSP depend on hydrogen retention parameters, such as trap concentration or activation energy of detrapping processes. The use of Arrhenius plots to characterize retention processes is then revisited when hydrogen trapping takes place during TDS experiments. Retention processes are also characterized using the shape of desorption peaks in TDSP, and it is shown that diffusion of hydrogen in material during TDS experiment can induce long desorption tails visible aside desorption peaks at high temperature in TDSP. These desorption tails can be used to estimate activation energy of diffusion of hydrogen in material.

  10. One-zone synchrotron self-Compton model for the core emission of Centaurus A revisited

    NASA Astrophysics Data System (ADS)

    Petropoulou, M.; Lefa, E.; Dimitrakoudis, S.; Mastichiadis, A.

    2014-02-01

    Aims: We investigate the role of the second synchrotron self-Compton (SSC) photon generation to the multiwavelength emission from the compact regions of sources that are characterized as misaligned blazars. For this, we focus on the nearest high-energy emitting radio galaxy Centaurus A and we revisit the one-zone SSC model for its core emission. Methods: We have calculated analytically the peak luminosities of the first and second SSC components by first deriving the steady-state electron distribution in the presence of synchrotron and SSC cooling, and then by using appropriate expressions for the positions of the spectral peaks. We have also tested our analytical results against those derived from a numerical code where the full emissivities and cross-sections were used. Results: We show that the one-zone SSC model cannot account for the core emission of Centaurus A above a few GeV, where the peak of the second SSC component appears. We thus propose an alternative explanation for the origin of the high-energy (?0.4 GeV) and TeV emission, where these are attributed to the radiation emitted by a relativistic proton component through photohadronic interactions with the photons produced by the primary leptonic component. We show that the required proton luminosities are not extremely high, i.e. ~1043 erg/s, provided that the injection spectra are modelled by a power law with a high value of the lower energy cutoff. Finally, we find that the contribution of the core emitting region of Cen A to the observed neutrino and ultra-high-energy cosmic-ray fluxes is negligible.

  11. Revisiting the monopole components of effective interactions for the shell model

    NASA Astrophysics Data System (ADS)

    Wang, X. B.; Dong, G. X.

    2015-12-01

    In this paper, we revisit the monopole components of effective interactions for the shell model. Without going through specific nuclei or shell gaps, universal roles of central, tensor, and spinorbit forces can be proved, reflecting the intrinsic features of shell model effective interactions. For monopole matrix elements, even and odd channels of central force often have a canceling effect. However, for the contributions to the shell evolution, its even and odd channels could have both positive or negative contributions, enhancing the role of central force on the shell structure. Tensor force is generally weaker than central force. However, for the effect on shell evolutions, tensor force can dominate or play a competitive role. A different systematics has been discovered between T = 1 and 0 channels. For example, tensor force, well established in the T = 0 channel, becomes uncertain in the T = 1 channel. We calculate the properties of neutron-rich oxygen and calcium isotopes in order to study T = 1 channel interactions further. It is learned that the main improvements of empirical interactions are traced to the central force. For non-central forces, antisymmetric spinorbit (ALS) force, originated from many-body perturbations or three-body force, could also play an explicit role. T = 1 tensor forces are less constrained so their effect can differ in different empirical interactions. The influence of tensor force may sometimes be canceled by many-body effects. For T = 0 channels of effective interactions, which is the main source of neutronproton correlations, central and tensor forces are the leading components. For T = 1 channels, which can act between like-particles, the request for many-body correlations could be more demanding, so that the monopole anomaly of the T = 1 channel might be more serious.

  12. Making Productive Use of Four Models of School English: A Case Study Revisited

    ERIC Educational Resources Information Center

    Macken-Horarik, Mary

    2014-01-01

    At a time when political leaders and media pundits seek to narrow the English curriculum and reduce its knowledge structure to the "basics," it is helpful to revisit the potential of different approaches to learning in English that have evolved over time. In this paper I reflect on the semantic features of personal growth, cultural

  13. Disappearing Scales in Carps: Re-Visiting Kirpichnikov's Model on the Genetics of Scale Pattern Formation

    PubMed Central

    Goh, Chin Heng; Kathiresan, Purushothaman; Nmeth, Sndor; Jeney, Zsigmond; Bercsnyi, Mikls; Orbn, Lszl

    2013-01-01

    The body of most fishes is fully covered by scales that typically form tight, partially overlapping rows. While some of the genes controlling the formation and growth of fish scales have been studied, very little is known about the genetic mechanisms regulating scale pattern formation. Although the existence of two genes with two pairs of alleles (S&s and N&n) regulating scale coverage in cyprinids has been predicted by Kirpichnikov and colleagues nearly eighty years ago, their identity was unknown until recently. In 2009, the S gene was found to be a paralog of fibroblast growth factor receptor 1, fgfr1a1, while the second gene called N has not yet been identified. We re-visited the original model of Kirpichnikov that proposed four major scale pattern types and observed a high degree of variation within the so-called scattered phenotype due to which this group was divided into two sub-types: classical mirror and irregular. We also analyzed the survival rates of offspring groups and found a distinct difference between Asian and European crosses. Whereas nude nude crosses involving at least one parent of Asian origin or hybrid with Asian parent(s) showed the 25% early lethality predicted by Kirpichnikov (due to the lethality of the NN genotype), those with two Hungarian nude parents did not. We further extended Kirpichnikov's work by correlating changes in phenotype (scale-pattern) to the deformations of fins and losses of pharyngeal teeth. We observed phenotypic changes which were not restricted to nudes, as described by Kirpichnikov, but were also present in mirrors (and presumably in linears as well; not analyzed in detail here). We propose that the gradation of phenotypes observed within the scattered group is caused by a gradually decreasing level of signaling (a dose-dependent effect) probably due to a concerted action of multiple pathways involved in scale formation. PMID:24386179

  14. Disappearing scales in carps: re-visiting Kirpichnikov's model on the genetics of scale pattern formation.

    PubMed

    Casas, Laura; Sz?cs, Rka; Vij, Shubha; Goh, Chin Heng; Kathiresan, Purushothaman; Nmeth, Sndor; Jeney, Zsigmond; Bercsnyi, Mikls; Orbn, Lszl

    2013-01-01

    The body of most fishes is fully covered by scales that typically form tight, partially overlapping rows. While some of the genes controlling the formation and growth of fish scales have been studied, very little is known about the genetic mechanisms regulating scale pattern formation. Although the existence of two genes with two pairs of alleles (S&s and N&n) regulating scale coverage in cyprinids has been predicted by Kirpichnikov and colleagues nearly eighty years ago, their identity was unknown until recently. In 2009, the 'S' gene was found to be a paralog of fibroblast growth factor receptor 1, fgfr1a1, while the second gene called 'N' has not yet been identified. We re-visited the original model of Kirpichnikov that proposed four major scale pattern types and observed a high degree of variation within the so-called scattered phenotype due to which this group was divided into two sub-types: classical mirror and irregular. We also analyzed the survival rates of offspring groups and found a distinct difference between Asian and European crosses. Whereas nude nude crosses involving at least one parent of Asian origin or hybrid with Asian parent(s) showed the 25% early lethality predicted by Kirpichnikov (due to the lethality of the NN genotype), those with two Hungarian nude parents did not. We further extended Kirpichnikov's work by correlating changes in phenotype (scale-pattern) to the deformations of fins and losses of pharyngeal teeth. We observed phenotypic changes which were not restricted to nudes, as described by Kirpichnikov, but were also present in mirrors (and presumably in linears as well; not analyzed in detail here). We propose that the gradation of phenotypes observed within the scattered group is caused by a gradually decreasing level of signaling (a dose-dependent effect) probably due to a concerted action of multiple pathways involved in scale formation. PMID:24386179

  15. Slow strain waves in the Earth: observational evidence and models

    NASA Astrophysics Data System (ADS)

    Bykov, Victor

    2014-05-01

    Recent remarkable progress in theoretical studies of the solitary strain waves, that have contributed greatly to the solution of the fundamental problem of strain waves in the Earth, is overviewed. The concept of strain waves generated in the Earth is based on the results of the study of earthquake distribution and slow tectonic deformation processes and the transfer of geophysical field anomalies. Propagation of strain waves is represented quantitatively by the rates of earthquake migration and geophysical responses to active faulting. These processes, and possibly the related strain waves, are either of global (global tectonic waves) or local (strain waves in faults) scales (Bykov, 2005). Global tectonic waves propagating at velocities from 10 to 100 km/yr are detected from migration of large earthquakes (Stein et al., 1997), seismic velocity anomalies (Nevsky et al., 1987), offsets of water level in wells along faults (Barabanov et al. 1988), or from transient displacement of seismic reflectors (Bazavluk and Yudakhin, 1993). Strain waves along crustal faults at velocities of 1-10 km/day are inferred from radon, electrokinetic and hydrogeodynamic signals, such as solitary waves (Nikolaevskiy, 1998). Migration of episodic tremor and slow slip events along plate boundaries in subduction zones and transform fault zones at a rate of 10 km/day, on an average (Schwartz and Rokosky, 2007), may be new evidence and indication of strain waves in the Earth. The detected mechanisms of strain wave exciting are caused by the block and microplate rotation, relative block displacement in crustal fault zones, transform faults, zones of the lithospheric plate collision and subduction and irregularity of the Earth's rotation (Bykov, 2005). These waves in the shape of kinks or solitons moving at velocities a great number of orders less than those of the ordinary seismic waves provide the possibility to explain slow stress redistribution in the crust. During a recent decade the sine-Gordon equation has been successfully applied for mathematical modeling of mechanisms of rotation and slippage of the crustal blocks generating slow solitary strain waves (Nikolaevskiy, 1995, 1996; Garagash, 1996; Mikhailov and Nikolaevskiy, 2000; Bykov, 2001, 2008; Gershenzon et al., 2009, 2011). Development of these models was motivated, in the first place, by an intention to obtain equation solutions in the shape of slow solitary inertial strain waves. The elasticity, or viscoelasticity, or elastoplasticity models (without account of blocks rotation) do not produce such results. The principal goals of an overview are: (i) to give observational data of seismic migration and strain waves; (ii) to demonstrate mathematical models of fault-block geological media, leading to the classical or perturbed sine-Gordon equations; (iii) to show the application of mathematical models for explanation of the observed effects in geological media.

  16. Lakatos Revisited.

    ERIC Educational Resources Information Center

    Court, Deborah

    1999-01-01

    Revisits and reviews Imre Lakatos' ideas on "Falsification and the Methodology of Scientific Research Programmes." Suggests that Lakatos' framework offers an insightful way of looking at the relationship between theory and research that is relevant not only for evaluating research programs in theoretical physics, but in the social sciences as

  17. Modeling Anti-HIV Activity of HEPT Derivatives Revisited. Multiregression Models Are Not Inferior Ones

    SciTech Connect

    Basic, Ivan; Nadramija, Damir; Flajslik, Mario; Amic, Dragan; Lucic, Bono

    2007-12-26

    Several quantitative structure-activity studies for this data set containing 107 HEPT derivatives have been performed since 1997, using the same set of molecules by (more or less) different classes of molecular descriptors. Multivariate Regression (MR) and Artificial Neural Network (ANN) models were developed and in each study the authors concluded that ANN models are superior to MR ones. We re-calculated multivariate regression models for this set of molecules using the same set of descriptors, and compared our results with the previous ones. Two main reasons for overestimation of the quality of the ANN models in previous studies comparing with MR models are: (1) wrong calculation of leave-one-out (LOO) cross-validated (CV) correlation coefficient for MR models in Luco et al., J. Chem. Inf. Comput. Sci. 37 392-401 (1997), and (2) incorrect estimation/interpretation of leave-one-out (LOO) cross-validated and predictive performance and power of ANN models. More precise and fairer comparison of fit and LOO CV statistical parameters shows that MR models are more stable. In addition, MR models are much simpler than ANN ones. For real testing the predictive performance of both classes of models we need more HEPT derivatives, because all ANN models that presented results for external set of molecules used experimental values in optimization of modeling procedure and model parameters.

  18. ETHICAL MODELS OF PHYSICIAN--PATIENT RELATIONSHIP REVISITED WITH REGARD TO PATIENT AUTONOMY, VALUES AND PATIENT EDUCATION.

    PubMed

    Borza, Liana Rada; Gavrilovici, Cristina; Stockman, Ren

    2015-01-01

    The present paper revisits the ethical models of patient--physician relationship from the perspective of patient autonomy and values. It seems that the four traditional models of physician--patient relationship proposed by Emanuel & Emanuel in 1992 closely link patient values and patient autonomy. On the other hand, their reinterpretation provided by Agarwal & Murinson twenty years later emphasizes the independent expression of values and autonomy in individual patients. Additionally, patient education has been assumed to join patient values and patient autonomy. Moreover, several authors have noted that, over the past few decades, patient autonomy has gradually replaced the paternalistic approach based on the premise that the physician knows what is best for the patient. Neither the paternalistic model of physician-patient relationship, nor the informative model is considered to be satisfactory, as the paternalistic model excludes patient values from decision making, while the informative model excludes physician values from decision making. However, the deliberative model of patient-physician interaction represents an adequate alternative to the two unsatisfactory approaches by promoting shared decision making between the physician and the patient. It has also been suggested that the deliberative model would be ideal for exercising patient autonomy in chronic care and that the ethical role of patient education would be to make the deliberative model applicable to chronic care. In this regard, studies have indicated that the use of decision support interventions might increase the deliberative capacity of chronic patients. PMID:26204658

  19. Revisiting Runoff Model Calibration: Airborne Snow Observatory Results Allow Improved Modeling Results

    NASA Astrophysics Data System (ADS)

    McGurk, B. J.; Painter, T. H.

    2014-12-01

    Deterministic snow accumulation and ablation simulation models are widely used by runoff managers throughout the world to predict runoff quantities and timing. Model fitting is typically based on matching modeled runoff volumes and timing with observed flow time series at a few points in the basin. In recent decades, sparse networks of point measurements of the mountain snowpacks have been available to compare with modeled snowpack, but the comparability of results from a snow sensor or course to model polygons of 5 to 50 sq. km is suspect. However, snowpack extent, depth, and derived snow water equivalent have been produced by the NASA/JPL Airborne Snow Observatory (ASO) mission for spring of 20013 and 2014 in the Tuolumne River basin above Hetch Hetchy Reservoir. These high-resolution snowpack data have exposed the weakness in a model calibration based on runoff alone. The U.S. Geological Survey's Precipitation Runoff Modeling System (PRMS) calibration that was based on 30-years of inflow to Hetch Hetchy produces reasonable inflow results, but modeled spatial snowpack location and water quantity diverged significantly from the weekly measurements made by ASO during the two ablation seasons. The reason is that the PRMS model has many flow paths, storages, and water transfer equations, and a calibrated outflow time series can be right for many wrong reasons. The addition of a detailed knowledge of snow extent and water content constrains the model so that it is a better representation of the actual watershed hydrology. The mechanics of recalibrating PRMS to the ASO measurements will be described, and comparisons in observed versus modeled flow for both a small subbasin and the entire Hetch Hetchy basin will be shown. The recalibrated model provided a bitter fit to the snowmelt recession, a key factor for water managers as they balance declining inflows with demand for power generation and ecosystem releases during the final months of snow melt runoff.

  20. SeaRISE experiments revisited: potential sources of spread in multi-model projections of the Greenland ice sheet

    NASA Astrophysics Data System (ADS)

    Saito, F.; Abe-Ouchi, A.; Takahashi, K.; Blatter, H.

    2016-01-01

    The present paper revisits the future surface-climate experiments on the Greenland ice sheet proposed by the Sea-level Response to Ice Sheet Evolution (SeaRISE; Bindschadler et al., 2013) study. The projections of the different SeaRISE participants show dispersion, which has not been examined in detail to date. A series of sensitivity experiments are conducted and analyzed using the ice-sheet model for integrated Earth-system studies (IcIES) by replacing one or more formulations of the model parameters with those adopted in other model(s). The results show that large potential sources of the dispersion among the projections of the different SeaRISE participants are differences in the initialization methods and in the surface mass balance methods, and both aspects have almost equal impact on the results. The treatment of ice-sheet margins in the simulation has a secondary impact on the dispersion. We conclude that spinning up the model using fixed topography through the spin-up period while the temperature is allowed to evolve according to the surface temperature history is the preferred representation, at least for the experiment configuration examined in the present paper. A benchmark model experimental setup that most of the numerical models can perform is proposed for future intercomparison projects, in order to evaluate the uncertainties relating to pure ice-sheet model flow characteristics.

  1. Local conformational perturbations of the DNA molecule in the SG-model

    NASA Astrophysics Data System (ADS)

    Krasnobaeva, L. A.; Shapovalov, A. V.

    2015-11-01

    Within the formalism of the Fokker-Planck equation, the influence of nonstationary external force, random force, and dissipation effects on dynamics local conformational perturbations (kink) propagating along the DNA molecule is investigated. Such waves have an important role in the regulation of important biological processes in living systems at the molecular level. As a dynamic model of DNA was used a modified sine-Gordon equation, simulating the rotational oscillations of bases in one of the chains DNA. The equation of evolution of the kink momentum is obtained in the form of the stochastic differential equation in the Stratonovich sense within the framework of the well-known McLaughlin and Scott energy approach. The corresponding Fokker-Planck equation for the momentum distribution function coincides with the equation describing the Ornstein-Uhlenbek process with a regular nonstationary external force. The influence of the nonlinear stochastic effects on the kink dynamics is considered with the help of the Fokker- Planck nonlinear equation with the shift coefficient dependent on the first moment of the kink momentum distribution function. Expressions are derived for average value and variance of the momentum. Examples are considered which demonstrate the influence of the external regular and random forces on the evolution of the average value and variance of the kink momentum. Within the formalism of the Fokker-Planck equation, the influence of nonstationary external force, random force, and dissipation effects on the kink dynamics is investigated in the sine-Gordon model. The equation of evolution of the kink momentum is obtained in the form of the stochastic differential equation in the Stratonovich sense within the framework of the well-known McLaughlin and Scott energy approach. The corresponding Fokker-Planck equation for the momentum distribution function coincides with the equation describing the Ornstein-Uhlenbek process with a regular nonstationary external force. The influence of the nonlinear stochastic effects on the kink dynamics is considered with the help of the Fokker-Planck nonlinear equation with the shift coefficient dependent on the first moment of the kink momentum distribution function. Expressions are derived for average value and variance of the momentum. Examples are considered which demonstrate the influence of the external regular and random forces on the evolution of the average value and variance of the kink momentum.

  2. Quantum mass shift of the soliton in the Skyrme model

    NASA Astrophysics Data System (ADS)

    Livne, Hillel

    1993-02-01

    The quantum mass shift of the soliton in the Skyrme model has been calculated from all nonzero modes. The calculations were carried out using a method applied earlier to the sine-Gordon model. The mass shifts do not depend on the baryonic spin, therefore they are the same for the nucleon and the Δ. Our model parameters are the pion decay constant Fπ, with its experimental value, and the pionic mass mπ, once in the chiral limit mπ=0 and also with the experimental value. We justify taking for the Skyrme parameter e the experimental value of gρππ, the mesonic ρ-pion coupling constant. The results depend on the vibrational energy. In this case an energy cutoff must be introduced. Using renormalization considerations as in the nonlinear σ model, we have chosen this cutoff to be eFπ=1136 MeV. Our results (for e=gρππ=6.11 and Fπ=186 MeV) are MN=996 MeV, MΔ=1593 MeV for mπ=0 MN=857 MeV, MΔ=1641 MeV for mπ=138 MeV. The spin dependence and the energy contribution of the coupling term between vibrations and rotations are being considered here only in a qualitative way.

  3. Benzophenone Ultrafast Triplet Population: Revisiting the Kinetic Model by Surface-Hopping Dynamics

    PubMed Central

    2016-01-01

    The photochemistry of benzophenone, a paradigmatic organic molecule for photosensitization, was investigated by means of surface-hopping ab initio molecular dynamics. Different mechanisms were found to be relevant within the first 600 fs after excitation; the long-debated direct (S1 → T1) and indirect (S1 → T2 → T1) mechanisms for population of the low-lying triplet state are both possible, with the latter being prevalent. Moreover, we established the existence of a kinetic equilibrium between the two triplet states, never observed before. This fact implies that a significant fraction of the overall population resides in T2, eventually allowing one to revisit the usual spectroscopic assignment proposed by transient absorption spectroscopy. This finding is of particular interest for photocatalysis as well as for DNA damages studies because both T1 and T2 channels are, in principle, available for benzophenone-mediated photoinduced energy transfer toward DNA. PMID:26821061

  4. Benzophenone Ultrafast Triplet Population: Revisiting the Kinetic Model by Surface-Hopping Dynamics.

    PubMed

    Marazzi, Marco; Mai, Sebastian; Roca-Sanjun, Daniel; Delcey, Mickal G; Lindh, Roland; Gonzlez, Leticia; Monari, Antonio

    2016-02-18

    The photochemistry of benzophenone, a paradigmatic organic molecule for photosensitization, was investigated by means of surface-hopping ab initio molecular dynamics. Different mechanisms were found to be relevant within the first 600 fs after excitation; the long-debated direct (S1 ? T1) and indirect (S1 ? T2 ? T1) mechanisms for population of the low-lying triplet state are both possible, with the latter being prevalent. Moreover, we established the existence of a kinetic equilibrium between the two triplet states, never observed before. This fact implies that a significant fraction of the overall population resides in T2, eventually allowing one to revisit the usual spectroscopic assignment proposed by transient absorption spectroscopy. This finding is of particular interest for photocatalysis as well as for DNA damages studies because both T1 and T2 channels are, in principle, available for benzophenone-mediated photoinduced energy transfer toward DNA. PMID:26821061

  5. Ries crater and suevite revisitedObservations and modeling Part II: Modeling

    NASA Astrophysics Data System (ADS)

    Artemieva, N. A.; Wnnemann, K.; Krien, F.; Reimold, W. U.; Stffler, D.

    2013-04-01

    We present the results of numerical modeling of the formation of the Ries crater utilizing the two hydrocodes SOVA and iSALE. These standard models allow us to reproduce crater shape, size, and morphology, and composition and extension of the continuous ejecta blanket. Some of these results cannot, however, be readily reconciled with observations: the impact plume above the crater consists mainly of molten and vaporized sedimentary rocks, containing very little material in comparison with the ejecta curtain; at the end of the modification stage, the crater floor is covered by a thick layer of impact melt with a total volume of 6-11 km3; the thickness of true fallback material from the plume inside the crater does not exceed a couple of meters; ejecta from all stratigraphic units of the target are transported ballistically; no separation of sedimentary and crystalline rocksas observed between suevites and Bunte Breccia at Riesis noted. We also present numerical results quantifying the existing geological hypotheses of Ries ejecta emplacement from an impact plume, by melt flow, or by a pyroclastic density current. The results show that none of these mechanisms is consistent with physical constraints and/or observations. Finally, we suggest a new hypothesis of suevite formation and emplacement by postimpact interaction of hot impact melt with water or volatile-rich sedimentary rocks.

  6. Revisiting a model of ontogenetic growth: estimating model parameters from theory and data.

    PubMed

    Moses, Melanie E; Hou, Chen; Woodruff, William H; West, Geoffrey B; Nekola, Jeffery C; Zuo, Wenyun; Brown, James H

    2008-05-01

    The ontogenetic growth model (OGM) of West et al. provides a general description of how metabolic energy is allocated between production of new biomass and maintenance of existing biomass during ontogeny. Here, we reexamine the OGM, make some minor modifications and corrections, and further evaluate its ability to account for empirical variation on rates of metabolism and biomass in vertebrates both during ontogeny and across species of varying adult body size. We show that the updated version of the model is internally consistent and is consistent with other predictions of metabolic scaling theory and empirical data. The OGM predicts not only the near universal sigmoidal form of growth curves but also the M(1/4) scaling of the characteristic times of ontogenetic stages in addition to the curvilinear decline in growth efficiency described by Brody. Additionally, the OGM relates the M(3/4) scaling across adults of different species to the scaling of metabolic rate across ontogeny within species. In providing a simple, quantitative description of how energy is allocated to growth, the OGM calls attention to unexplained variation, unanswered questions, and opportunities for future research. PMID:18419571

  7. Kink topology control by high-frequency external forces in nonlinear Klein-Gordon models.

    PubMed

    Alvarez-Nodarse, R; Quintero, N R; Mertens, F G

    2014-10-01

    A method of averaging is applied to study the dynamics of a kink in the damped double sine-Gordon equation driven by both external (nonparametric) and parametric periodic forces at high frequencies. This theoretical approach leads to the study of a double sine-Gordon equation with an effective potential and an effective additive force. Direct numerical simulations show how the appearance of two connected ? kinks and of an individual ? kink can be controlled via the frequency. An anomalous negative mobility phenomenon is also predicted by theory and confirmed by simulations of the original equation. PMID:25375576

  8. The population genetics of Trypanosoma cruzi revisited in the light of the predominant clonal evolution model.

    PubMed

    Tibayrenc, Michel; Ayala, Francisco J

    2015-11-01

    Comparing the population structure of Trypanosoma cruzi with that of other pathogens, including parasitic protozoa, fungi, bacteria and viruses, shows that the agent of Chagas disease shares typical traits with many other species, related to a predominant clonal evolution (PCE) pattern: statistically significant linkage disequilibrium, overrepresented multilocus genotypes, near-clades (genetic subdivisions somewhat blurred by occasional genetic exchange/hybridization) and "Russian doll" patterns (PCE is observed, not only at the level of the whole species, but also, within the near-clades). Moreover, T. cruzi population structure exhibits linkage with the diversity of several strongly selected genes, with gene expression profiles, and with some major phenotypic traits. We discuss the evolutionary significance of these results, and their implications in terms of applied research (molecular epidemiology/strain typing, analysis of genes of interest, vaccine and drug design, immunological diagnosis) and of experimental evolution. Lastly, we revisit the long-term debate of describing new species within the T. cruzi taxon. PMID:26188332

  9. Ups and Downs of Viagra: Revisiting Ototoxicity in the Mouse Model

    PubMed Central

    Au, Adrian; Stuyt, John Gerka; Chen, Daniel; Alagramam, Kumar

    2013-01-01

    Sildenafil citrate (Viagra), a phosphodiesterase 5 inhibitor (PDE5i), is a commonly prescribed drug for erectile dysfunction. Since the introduction of Viagra in 1997, several case reports have linked Viagra to sudden sensorineural hearing loss. However, these studies are not well controlled for confounding factors, such as age and noise-induced hearing loss and none of these reports are based on prospective double-blind studies. Further, animal studies report contradictory data. For example, one study (2008) reported hearing loss in rats after long-term and high-dose exposure to sildenafil citrate. The other study (2012) showed vardenafil, another formulation of PDE5i, to be protective against noise-induced hearing loss in mice and rats. Whether or not clinically relevant doses of sildenafil citrate cause hearing loss in normal subjects (animals or humans) is controversial. One possibility is that PDE5i exacerbates age-related susceptibility to hearing loss in adults. Therefore, we tested sildenafil citrate in C57BL/6J, a strain of mice that displays increased susceptibility to age-related hearing loss, and compared the results to those obtained from the FVB/N, a strain of mice with no predisposition to hearing loss. Six-week-old mice were injected with the maximum tolerated dose of sildenafil citrate (10 mg/kg/day) or saline for 30 days. Auditory brainstem responses (ABRs) were recorded pre- and post injection time points to assess hearing loss. Entry of sildenafil citrate in the mouse cochlea was confirmed by qRT-PCR analysis of a downstream target of the cGMP-PKG cascade. ABR data indicated no statistically significant difference in hearing between treated and untreated mice in both backgrounds. Results show that the maximum tolerated dose of sildenafil citrate administered daily for 4 weeks does not affect hearing in the mouse. Our study gives no indication that Viagra will negatively impact hearing and it emphasizes the need to revisit the issue of Viagra related ototoxicity in humans. PMID:24244454

  10. Revisiting a Statistical Shortcoming When Fitting the Langmuir Model to Sorption Data

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Langmuir model is commonly used for describing sorption behavior of reactive solutes to surfaces. Fitting the Langmuir model to sorption data requires either the use of nonlinear regression or, alternatively, linear regression using one of the linearized versions of the model. Statistical limit...

  11. Revisiting single photon avalanche diode current-voltage modeling and transient characteristics

    SciTech Connect

    Javitt, M.; Savuskan, V. Merhav, T.; Nemirovsky, Y.

    2014-05-28

    A model for the current-voltage and transient behavior of Single Photon Avalanche Diodes (SPADs) based on device physics is presented. The results of the model are compared to actual measurements and a reasonable fit is seen. Additionally, the model provides a useful tool for designing quenching circuitry and determining optimal operation conditions of the SPAD.

  12. Revisiting Fixed- and Random-Effects Models: Some Considerations for Policy-Relevant Education Research

    ERIC Educational Resources Information Center

    Clarke, Paul; Crawford, Claire; Steele, Fiona; Vignoles, Anna

    2015-01-01

    The use of fixed (FE) and random effects (RE) in two-level hierarchical linear regression is discussed in the context of education research. We compare the robustness of FE models with the modelling flexibility and potential efficiency of those from RE models. We argue that the two should be seen as complementary approaches. We then compare both…

  13. Revisiting Fixed- and Random-Effects Models: Some Considerations for Policy-Relevant Education Research

    ERIC Educational Resources Information Center

    Clarke, Paul; Crawford, Claire; Steele, Fiona; Vignoles, Anna

    2015-01-01

    The use of fixed (FE) and random effects (RE) in two-level hierarchical linear regression is discussed in the context of education research. We compare the robustness of FE models with the modelling flexibility and potential efficiency of those from RE models. We argue that the two should be seen as complementary approaches. We then compare both

  14. Revisiting Gaussian Process Regression Modeling for Localization in Wireless Sensor Networks.

    PubMed

    Richter, Philipp; Toledano-Ayala, Manuel

    2015-01-01

    Signal strength-based positioning in wireless sensor networks is a key technology for seamless, ubiquitous localization, especially in areas where Global Navigation Satellite System (GNSS) signals propagate poorly. To enable wireless local area network (WLAN) location fingerprinting in larger areas while maintaining accuracy, methods to reduce the effort of radio map creation must be consolidated and automatized. Gaussian process regression has been applied to overcome this issue, also with auspicious results, but the fit of the model was never thoroughly assessed. Instead, most studies trained a readily available model, relying on the zero mean and squared exponential covariance function, without further scrutinization. This paper studies the Gaussian process regression model selection for WLAN fingerprinting in indoor and outdoor environments. We train several models for indoor/outdoor- and combined areas; we evaluate them quantitatively and compare them by means of adequate model measures, hence assessing the fit of these models directly. To illuminate the quality of the model fit, the residuals of the proposed model are investigated, as well. Comparative experiments on the positioning performance verify and conclude the model selection. In this way, we show that the standard model is not the most appropriate, discuss alternatives and present our best candidate. PMID:26370996

  15. Revisiting Gaussian Process Regression Modeling for Localization in Wireless Sensor Networks

    PubMed Central

    Richter, Philipp; Toledano-Ayala, Manuel

    2015-01-01

    Signal strength-based positioning in wireless sensor networks is a key technology for seamless, ubiquitous localization, especially in areas where Global Navigation Satellite System (GNSS) signals propagate poorly. To enable wireless local area network (WLAN) location fingerprinting in larger areas while maintaining accuracy, methods to reduce the effort of radio map creation must be consolidated and automatized. Gaussian process regression has been applied to overcome this issue, also with auspicious results, but the fit of the model was never thoroughly assessed. Instead, most studies trained a readily available model, relying on the zero mean and squared exponential covariance function, without further scrutinization. This paper studies the Gaussian process regression model selection for WLAN fingerprinting in indoor and outdoor environments. We train several models for indoor/outdoor- and combined areas; we evaluate them quantitatively and compare them by means of adequate model measures, hence assessing the fit of these models directly. To illuminate the quality of the model fit, the residuals of the proposed model are investigated, as well. Comparative experiments on the positioning performance verify and conclude the model selection. In this way, we show that the standard model is not the most appropriate, discuss alternatives and present our best candidate. PMID:26370996

  16. The Two-Capacitor Problem Revisited: A Mechanical Harmonic Oscillator Model Approach

    ERIC Educational Resources Information Center

    Lee, Keeyung

    2009-01-01

    The well-known two-capacitor problem, in which exactly half the stored energy disappears when a charged capacitor is connected to an identical capacitor, is discussed based on the mechanical harmonic oscillator model approach. In the mechanical harmonic oscillator model, it is shown first that "exactly half" the work done by a constant applied…

  17. Susceptible-infectious-recovered models revisited: from the individual level to the population level.

    PubMed

    Magal, Pierre; Ruan, Shigui

    2014-04-01

    The classical susceptible-infectious-recovered (SIR) model, originated from the seminal papers of Ross [51] and Ross and Hudson [52,53] in 1916-1917 and the fundamental contributions of Kermack and McKendrick [36-38] in 1927-1932, describes the transmission of infectious diseases between susceptible and infective individuals and provides the basic framework for almost all later epidemic models, including stochastic epidemic models using Monte Carlo simulations or individual-based models (IBM). In this paper, by defining the rules of contacts between susceptible and infective individuals, the rules of transmission of diseases through these contacts, and the time of transmission during contacts, we provide detailed comparisons between the classical deterministic SIR model and the IBM stochastic simulations of the model. More specifically, for the purpose of numerical and stochastic simulations we distinguish two types of transmission processes: that initiated by susceptible individuals and that driven by infective individuals. Our analysis and simulations demonstrate that in both cases the IBM converges to the classical SIR model only in some particular situations. In general, the classical and individual-based SIR models are significantly different. Our study reveals that the timing of transmission in a contact at the individual level plays a crucial role in determining the transmission dynamics of an infectious disease at the population level. PMID:24530806

  18. Revisiting the Model of Creative Destruction: St. Jacobs, Ontario, a Decade Later

    ERIC Educational Resources Information Center

    Mitchell, Clare J. A.; de Waal, Sarah B.

    2009-01-01

    Ten years ago, the model of creative destruction was developed to predict the fate of communities that base their development on the commodification of rural heritage (Mitchell, C.J.A., 1998. Entrepreneurialism, commodification and creative destruction: a model of post-modern community development. Journal of Rural Studies 14, 273-286). Its…

  19. The Two-Capacitor Problem Revisited: A Mechanical Harmonic Oscillator Model Approach

    ERIC Educational Resources Information Center

    Lee, Keeyung

    2009-01-01

    The well-known two-capacitor problem, in which exactly half the stored energy disappears when a charged capacitor is connected to an identical capacitor, is discussed based on the mechanical harmonic oscillator model approach. In the mechanical harmonic oscillator model, it is shown first that "exactly half" the work done by a constant applied

  20. Revisiting the Model of Creative Destruction: St. Jacobs, Ontario, a Decade Later

    ERIC Educational Resources Information Center

    Mitchell, Clare J. A.; de Waal, Sarah B.

    2009-01-01

    Ten years ago, the model of creative destruction was developed to predict the fate of communities that base their development on the commodification of rural heritage (Mitchell, C.J.A., 1998. Entrepreneurialism, commodification and creative destruction: a model of post-modern community development. Journal of Rural Studies 14, 273-286). Its

  1. Gill's model of the Antarctic Circumpolar Current, revisited: The role of latitudinal variations in wind stress

    NASA Astrophysics Data System (ADS)

    Marshall, David P.; Munday, David R.; Allison, Lesley C.; Hay, Russell J.; Johnson, Helen L.

    2016-01-01

    Gill's (1968) model of the Antarctic Circumpolar Current (ACC) is reinterpreted for a stratified, reduced-gravity ocean, where the barotropic streamfunction is replaced by the pycnocline depth, and the bottom drag coefficient by the Gent and McWilliams eddy diffusivity. The resultant model gives a simple description of the lateral structure of the ACC that is consistent with contemporary descriptions of ACC dynamics. The model is used to investigate and interpret the sensitivity of the ACC to the latitudinal profile of the surface wind stress. A substantial ACC remains when the wind jet is shifted north of the model Drake Passage, even by several thousand kilometers. The integral of the wind stress over the circumpolar streamlines is found to be a useful predictor of the magnitude of the volume transport through the model Drake Passage, although it is necessary to correct for basin-wide zonal pressure gradients in order to obtain good quantitative agreement.

  2. Revisiting node-based SIR models in complex networks with degree correlations

    NASA Astrophysics Data System (ADS)

    Wang, Yi; Cao, Jinde; Alofi, Abdulaziz; AL-Mazrooei, Abdullah; Elaiw, Ahmed

    2015-11-01

    In this paper, we consider two growing networks which will lead to the degree-degree correlations between two nearest neighbors in the network. When the network grows to some certain size, we introduce an SIR-like disease such as pandemic influenza H1N1/09 to the population. Due to its rapid spread, the population size changes slowly, and thus the disease spreads on correlated networks with approximately fixed size. To predict the disease evolution on correlated networks, we first review two node-based SIR models incorporating degree correlations and an edge-based SIR model without considering degree correlation, and then compare the predictions of these models with stochastic SIR simulations, respectively. We find that the edge-based model, even without considering degree correlations, agrees much better than the node-based models incorporating degree correlations with stochastic SIR simulations in many respects. Moreover, simulation results show that for networks with positive correlation, the edge-based model provides a better upper bound of the cumulative incidence than the node-based SIR models, whereas for networks with negative correlation, it provides a lower bound of the cumulative incidence.

  3. The PANAS structure revisited: on the validity of a bifactor model in community and forensic samples.

    PubMed

    Leue, Anja; Beauducel, Andr

    2011-03-01

    The Positive and Negative Affect Schedule (PANAS) is a widely used inventory for the assessment of affect in psychology and other applied sciences. Despite its popularity, the structure of the PANAS is still under debate. On the one hand, there is evidence of the traditional 2-factor model with Positive Affect (PA) and Negative Affect (NA) as uncorrelated factors. On the other hand, a more complex structure of the PANAS has been discussed. To shed further light on the core dimensions of the PANAS, 2 studies investigated the structure of the PANAS in 2 German samples (N = 354 and N = 364, respectively) by means of confirmatory factor analysis. The factor analysis results of Study 1 for a traitlike time frame instruction suggested a suboptimal model fit for the uncorrelated 2-factor model and the 3-factor model with PA, Afraid, and Upset as factors, whereas a superior model fit occurred for a bifactor model with traitlike PA, NA, and a general 3rd factor named Affective Polarity. In Study 2, the bifactor model was replicated for a statelike PANAS time frame instruction and evidence of criterion validity was provided for PA, NA, and Affective Polarity factors in 2 sex offender subgroups and in a community sample. With Affective Polarity, we introduce an affect dimension that captures additional variance beyond PA and NA. Because of the adjectives with relevant loadings on Affective Polarity, this general factor represents an individual's orientation toward approach and withdrawal, respectively. PMID:21280952

  4. BrainSignals Revisited: Simplifying a Computational Model of Cerebral Physiology

    PubMed Central

    Caldwell, Matthew; Hapuarachchi, Tharindi; Highton, David; Elwell, Clare; Smith, Martin; Tachtsidis, Ilias

    2015-01-01

    Multimodal monitoring of brain state is important both for the investigation of healthy cerebral physiology and to inform clinical decision making in conditions of injury and disease. Near-infrared spectroscopy is an instrument modality that allows non-invasive measurement of several physiological variables of clinical interest, notably haemoglobin oxygenation and the redox state of the metabolic enzyme cytochrome c oxidase. Interpreting such measurements requires the integration of multiple signals from different sources to try to understand the physiological states giving rise to them. We have previously published several computational models to assist with such interpretation. Like many models in the realm of Systems Biology, these are complex and dependent on many parameters that can be difficult or impossible to measure precisely. Taking one such model, BrainSignals, as a starting point, we have developed several variant models in which specific regions of complexity are substituted with much simpler linear approximations. We demonstrate that model behaviour can be maintained whilst achieving a significant reduction in complexity, provided that the linearity assumptions hold. The simplified models have been tested for applicability with simulated data and experimental data from healthy adults undergoing a hypercapnia challenge, but relevance to different physiological and pathophysiological conditions will require specific testing. In conditions where the simplified models are applicable, their greater efficiency has potential to allow their use at the bedside to help interpret clinical data in near real-time. PMID:25961297

  5. The Goodwin model revisited: Hopf bifurcation, limit-cycle, and periodic entrainment

    NASA Astrophysics Data System (ADS)

    Woller, Aurore; Gonze, Didier; Erneux, Thomas

    2014-08-01

    The three-variable Goodwin oscillator is a minimal model demonstrating the emergence of oscillations in simple biochemical feedback systems. As a prototypical oscillator, this model was extensively studied from a theoretical point of view and applied to various biological systems, including circadian clocks. Here, we reexamine this model, derive analytically the amplitude equation near the Hopf bifurcation and investigate the effect of a periodic modulation of the oscillator. In particular, we compare the entrainment performance when the free oscillator displays either self-sustained or damped oscillations. We discuss the results in the context of circadian oscillators.

  6. Revisiting the Cape Cod Bacteria Injection Experiment Using a Stochastic Modeling Approach

    SciTech Connect

    Maxwell, R M; Welty, C; Harvey, R W

    2006-11-22

    Bromide and resting-cell bacteria tracer tests carried out in a sand and gravel aquifer at the USGS Cape Cod site in 1987 were reinterpreted using a three-dimensional stochastic approach and Lagrangian particle tracking numerical methods. Bacteria transport was strongly coupled to colloid filtration through functional dependence of local-scale colloid transport parameters on hydraulic conductivity and seepage velocity in a stochastic advection-dispersion/attachment-detachment model. Information on geostatistical characterization of the hydraulic conductivity (K) field from a nearby plot was utilized as input that was unavailable when the original analysis was carried out. A finite difference model for groundwater flow and a particle-tracking model of conservative solute transport was calibrated to the bromide-tracer breakthrough data using the aforementioned geostatistical parameters. An optimization routine was utilized to adjust the mean and variance of the lnK field over 100 realizations such that a best fit of a simulated, average bromide breakthrough curve is achieved. Once the optimal bromide fit was accomplished (based on adjusting the lnK statistical parameters in unconditional simulations), a stochastic particle-tracking model for the bacteria was run without adjustments to the local-scale colloid transport parameters. Good predictions of the mean bacteria breakthrough data were achieved using several approaches for modeling components of the system. Simulations incorporating the recent Tufenkji and Elimelech [1] equation for estimating single collector efficiency were compared to those using the Rajagopalan and Tien [2] model. Both appeared to work equally well at predicting mean bacteria breakthrough using a constant mean bacteria diameter for this set of field conditions, with the Rajagopalan and Tien model yielding approximately a 30% lower peak concentration and less tailing than the Tufenkji and Elimelech formulation. Simulations using a distribution of bacterial cell diameters available from original field notes yielded a slight improvement in the model and data agreement compared to simulations using an average bacteria diameter; variable bacterial cell diameters lowered the modeled peak concentrations and more significantly diminished the tailing behavior, particularly for the Rajagopalan and Tien model of collision frequency. Spatial variability in detachment had little effect on the results. The Lagrangian particle transport model representing the non-idealities of the colloid transport process appears to be a robust, grid-free method for modeling field-scale distribution problems where incorporation of fine-scale heterogeneity would necessitate large numbers of computational cells. The stochastic approach based on estimates of local-scale parameters for the bacteria-transport process both captures the mean field behavior of bacteria transport and calculates an envelope of uncertainty that brackets the observations in most simulation cases.

  7. A NEW APPROACH TO HYDROLOGIC MODELING: DERIVED DISTRIBUTIONS REVISITED. (R824780)

    EPA Science Inventory

    A fractal geometric procedure to model hydrologic (geophysical) phenomena is introduced. The method consists of using derived distributions, obtained by transforming arbitrary multinomial multifractal measures via fractal interpolating functions, to represent observed hydrologic ...

  8. The consensus in the two-feature two-state one-dimensional Axelrod model revisited

    NASA Astrophysics Data System (ADS)

    Biral, Elias J. P.; Tilles, Paulo F. C.; Fontanari, Jos F.

    2015-04-01

    The Axelrod model for the dissemination of culture exhibits a rich spatial distribution of cultural domains, which depends on the values of the two model parameters: F, the number of cultural features and q, the common number of states each feature can assume. In the one-dimensional model with F = q = 2, which is closely related to the constrained voter model, Monte Carlo simulations indicate the existence of multicultural absorbing configurations in which at least one macroscopic domain coexist with a multitude of microscopic ones in the thermodynamic limit. However, rigorous analytical results for the infinite system starting from the configuration where all cultures are equally likely show convergence to only monocultural or consensus configurations. Here we show that this disagreement is due simply to the order that the time-asymptotic limit and the thermodynamic limit are taken in the simulations. In addition, we show how the consensus-only result can be derived using Monte Carlo simulations of finite chains.

  9. Revisiting Turbulence Model Validation for High-Mach Number Axisymmetric Compression Corner Flows

    NASA Technical Reports Server (NTRS)

    Georgiadis, Nicholas J.; Rumsey, Christopher L.; Huang, George P.

    2015-01-01

    Two axisymmetric shock-wave/boundary-layer interaction (SWBLI) cases are used to benchmark one- and two-equation Reynolds-averaged Navier-Stokes (RANS) turbulence models. This validation exercise was executed in the philosophy of the NASA Turbulence Modeling Resource and the AIAA Turbulence Model Benchmarking Working Group. Both SWBLI cases are from the experiments of Kussoy and Horstman for axisymmetric compression corner geometries with SWBLI inducing flares of 20 and 30 degrees, respectively. The freestream Mach number was approximately 7. The RANS closures examined are the Spalart-Allmaras one-equation model and the Menter family of kappa - omega two equation models including the Baseline and Shear Stress Transport formulations. The Wind-US and CFL3D RANS solvers are employed to simulate the SWBLI cases. Comparisons of RANS solutions to experimental data are made for a boundary layer survey plane just upstream of the SWBLI region. In the SWBLI region, comparisons of surface pressure and heat transfer are made. The effects of inflow modeling strategy, grid resolution, grid orthogonality, turbulent Prandtl number, and code-to-code variations are also addressed.

  10. Stochastic dynamics and non-equilibrium thermodynamics of a bistable chemical system: the Schlgl model revisited

    PubMed Central

    Vellela, Melissa; Qian, Hong

    2009-01-01

    Schlgl's model is the canonical example of a chemical reaction system that exhibits bistability. Because the biological examples of bistability and switching behaviour are increasingly numerous, this paper presents an integrated deterministic, stochastic and thermodynamic analysis of the model. After a brief review of the deterministic and stochastic modelling frameworks, the concepts of chemical and mathematical detailed balances are discussed and non-equilibrium conditions are shown to be necessary for bistability. Thermodynamic quantities such as the flux, chemical potential and entropy production rate are defined and compared across the two models. In the bistable region, the stochastic model exhibits an exchange of the global stability between the two stable states under changes in the pump parameters and volume size. The stochastic entropy production rate shows a sharp transition that mirrors this exchange. A new hybrid model that includes continuous diffusion and discrete jumps is suggested to deal with the multiscale dynamics of the bistable system. Accurate approximations of the exponentially small eigenvalue associated with the time scale of this switching and the full time-dependent solution are calculated using Matlab. A breakdown of previously known asymptotic approximations on small volume scales is observed through comparison with these and Monte Carlo results. Finally, in the appendix section is an illustration of how the diffusion approximation of the chemical master equation can fail to represent correctly the mesoscopically interesting steady-state behaviour of the system. PMID:19095615

  11. Repeat topography surveys of geomorphic changes using digital surface models deriving from Formosat-2 daily revisit stereo pair with very narrow baseline

    NASA Astrophysics Data System (ADS)

    Liu, C.; Wen, H.; Liu, J.; Ko, M.; Yan, H.; Chang, L.

    2012-12-01

    Repeat topography surveys provides a geometrically-corrected frame with relief information, which is crucial for studying geomorphic changes after a major slope hazard, such as the debris flow or landslides. The successful operation of Formosat-2 has proved the concept that the temporal resolution of a remote sensing system can be much improved by deploying a high-spatial-resolution sensor in a daily revisit orbit, as each accessible scene can be systematically observed from the same angle under similar illumination conditions. These characteristics make Formosat-2 an ideal satellite for site surveillance, and its images have been successfully applied in environmental monitoring, hazard assessment, orthomap generation, rapidly responding to a global disaster event, and land use management. The attempt of using a Formosat-2 stereo pair to generate a DSM, however, has not been very successful up-to-date. Ironically, it is mainly due to the characteristics of daily-revisit orbit as well. According to the parallax equation, to obtain an accurate height estimation requires a high disparity precision from the stereo pair. The most convenient approach is to maximize the baseline B or the baseline/height (B/H) ratio to a preferred range 0.6 to 1. It is not feasible, however, to acquire an across-track stereo pair with that range of baseline from the daily-revisit orbit using Formosat-2. Even taking the orbit drifting into consideration, it would take a few months to achieve a B/H ratio of approximately 0.15 across track. Another approach is to acquire an along-track stereo pair. But for the mountainous areas, such as the central mountain areas, in Taiwan, the shaded effect and geometrically distortion are apparent. This prohibits any attempt to employ the automatic image matching technique to generate a DSM based on the disparities retrieved from Frmosat-2 along-track stereo pair directly. Phase correlation is operated in the frequency-domain, which enables the relative translative offset between two similar images to be rapidly estimated. To meet the requirements in remote sensing and biomedical imaging, the technology of phase correlation has been extended to the sub-pixel level. Liu and Yan (2008) developed a robust phase correlation model using the based feature matching for image co-registration and DEM generation. Considering the fact that the Formosat-2 consecutive images are intrinsically stereo pairs with very narrow baselines, this innovative stereo-matching algorithm based on SPPC technique is employed to process Formosat-2 daily revisit stereo pairs with very narrow baselines. The detailed accuracy and efficiency analysis is investigated for the study area, Namasha, Kaohsiung, using the 50cm resolution aerial photo and the 2m resolution DEM derived from airborne LiDAR data. The archive of Formosat-2 images in Taiwan area collected from 2005 to 2012 was screened out, with the intention to select the consecutive pairs of those areas where major slope disasters occurred in the past eight years. This research encourages the repeated topography surveys of geomorphic changes using digital surface models deriving from Formosat-2 daily revisit stereo pair with very narrow baseline.

  12. The raspberry model for hydrodynamic interactions revisited. I. Periodic arrays of spheres and dumbbells.

    PubMed

    Fischer, Lukas P; Peter, Toni; Holm, Christian; de Graaf, Joost

    2015-08-28

    The so-called "raspberry" model refers to the hybrid lattice-Boltzmann and Langevin molecular dynamics scheme for simulating the dynamics of suspensions of colloidal particles, originally developed by Lobaskin and Dnweg [New J. Phys. 6, 54 (2004)], wherein discrete surface points are used to achieve fluid-particle coupling. This technique has been used in many simulation studies on the behavior of colloids. However, there are fundamental questions with regards to the use of this model. In this paper, we examine the accuracy with which the raspberry method is able to reproduce Stokes-level hydrodynamic interactions when compared to analytic expressions for solid spheres in simple-cubic crystals. To this end, we consider the quality of numerical experiments that are traditionally used to establish these properties and we discuss their shortcomings. We show that there is a discrepancy between the translational and rotational mobility reproduced by the simple raspberry model and present a way to numerically remedy this problem by adding internal coupling points. Finally, we examine a non-convex shape, namely, a colloidal dumbbell, and show that the filled raspberry model replicates the desired hydrodynamic behavior in bulk for this more complicated shape. Our investigation is continued in de Graaf et al. [J. Chem. Phys. 143, 084108 (2015)], wherein we consider the raspberry model in the confining geometry of two parallel plates. PMID:26328818

  13. Revisiting the Rigidly Rotating Magnetosphere model for σ Ori E - I. Observations and data analysis

    NASA Astrophysics Data System (ADS)

    Oksala, M. E.; Wade, G. A.; Townsend, R. H. D.; Owocki, S. P.; Kochukhov, O.; Neiner, C.; Alecian, E.; Grunhut, J.

    2012-01-01

    We have obtained 18 new high-resolution spectropolarimetric observations of the B2Vp star σ Ori E with both the Narval and ESPaDOnS spectropolarimeters. The aim of these observations is to test, with modern data, the assumptions of the Rigidly Rotating Magnetosphere (RRM) model of Townsend & Owocki, applied to the specific case of σ Ori E by Townsend, Owocki & Groote. This model includes a substantially offset dipole magnetic field configuration, and approximately reproduces previous observational variations in longitudinal field strength, photometric brightness and Hα emission. We analyse new spectroscopy, including H I, He I, C II, Si III and Fe III lines, confirming the diversity of variability in photospheric lines, as well as the double S-wave variation of circumstellar hydrogen. Using the multiline analysis method of least-squares deconvolution (LSD), new, more precise longitudinal magnetic field measurements reveal a substantial variance between the shapes of the observed and RRM model time-varying field. The phase-resolved Stokes V profiles of He I 5876 and 6678 Å lines are fitted poorly by synthetic profiles computed from the magnetic topology assumed by Townsend et al.. These results challenge the offset dipole field configuration assumed in the application of the RRM model to σ Ori E, and indicate that future models of its magnetic field should also include complex, higher order components. Footnotes<label>1</label></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JChPh.143h4107F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JChPh.143h4107F"><span id="translatedtitle">The raspberry <span class="hlt">model</span> for hydrodynamic interactions <span class="hlt">revisited</span>. I. Periodic arrays of spheres and dumbbells</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fischer, Lukas P.; Peter, Toni; Holm, Christian; de Graaf, Joost</p> <p>2015-08-01</p> <p>The so-called "raspberry" <span class="hlt">model</span> refers to the hybrid lattice-Boltzmann and Langevin molecular dynamics scheme for simulating the dynamics of suspensions of colloidal particles, originally developed by Lobaskin and Dünweg [New J. Phys. 6, 54 (2004)], wherein discrete surface points are used to achieve fluid-particle coupling. This technique has been used in many simulation studies on the behavior of colloids. However, there are fundamental questions with regards to the use of this <span class="hlt">model</span>. In this paper, we examine the accuracy with which the raspberry method is able to reproduce Stokes-level hydrodynamic interactions when compared to analytic expressions for solid spheres in simple-cubic crystals. To this end, we consider the quality of numerical experiments that are traditionally used to establish these properties and we discuss their shortcomings. We show that there is a discrepancy between the translational and rotational mobility reproduced by the simple raspberry <span class="hlt">model</span> and present a way to numerically remedy this problem by adding internal coupling points. Finally, we examine a non-convex shape, namely, a colloidal dumbbell, and show that the filled raspberry <span class="hlt">model</span> replicates the desired hydrodynamic behavior in bulk for this more complicated shape. Our investigation is continued in de Graaf et al. [J. Chem. Phys. 143, 084108 (2015)], wherein we consider the raspberry <span class="hlt">model</span> in the confining geometry of two parallel plates.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/21599150','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/21599150"><span id="translatedtitle">Two-ball problem <span class="hlt">revisited</span>: limitations of event-driven <span class="hlt">modeling</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Mller, Patric; Pschel, Thorsten</p> <p>2011-04-01</p> <p>The main precondition of simulating systems of hard particles by means of event-driven <span class="hlt">modeling</span> is the assumption of instantaneous collisions. The aim of this paper is to quantify the deviation of event-driven <span class="hlt">modeling</span> from the solution of Newton's equation of motion using a paradigmatic example: If a tennis ball is held above a basketball with their centers vertically aligned, and the balls are released to collide with the floor, the tennis ball may rebound at a surprisingly high speed. We show in this article that the simple textbook explanation of this effect is an oversimplification, even for the limit of perfectly elastic particles. Instead, there may occur a rather complex scenario including multiple collisions which may lead to a very different final velocity as compared with the velocity resulting from the oversimplified <span class="hlt">model</span>. PMID:21599150</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011PhRvE..83d1304M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011PhRvE..83d1304M"><span id="translatedtitle">Two-ball problem <span class="hlt">revisited</span>: Limitations of event-driven <span class="hlt">modeling</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mller, Patric; Pschel, Thorsten</p> <p>2011-04-01</p> <p>The main precondition of simulating systems of hard particles by means of event-driven <span class="hlt">modeling</span> is the assumption of instantaneous collisions. The aim of this paper is to quantify the deviation of event-driven <span class="hlt">modeling</span> from the solution of Newtons equation of motion using a paradigmatic example: If a tennis ball is held above a basketball with their centers vertically aligned, and the balls are released to collide with the floor, the tennis ball may rebound at a surprisingly high speed. We show in this article that the simple textbook explanation of this effect is an oversimplification, even for the limit of perfectly elastic particles. Instead, there may occur a rather complex scenario including multiple collisions which may lead to a very different final velocity as compared with the velocity resulting from the oversimplified <span class="hlt">model</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1998EPJAP...1..119Q','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1998EPJAP...1..119Q"><span id="translatedtitle">Rheological <span class="hlt">modelling</span> of complex fluids. I. The concept of effective volume fraction <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Quemada, D.</p> <p>1998-01-01</p> <p>Number of complex fluids (as slurries, drilling muds, paints and coatings, many foods, cosmetics, biofluids...) can approximately be described as concentrated dispersions of Structural Units (SUs). Due to shear forces, SUs are assumed to be approximately spherical in shape and uniform in size under steady flow conditions, so that a complex fluid can be considered as a roughly monodisperse dispersion of roughly spherical SUs (with a shear-dependent mean radius), what allows to generalize hard sphere <span class="hlt">models</span> of monodisperse suspensions to complex fluids. A rheological <span class="hlt">model</span> of such dispersions of SUs is based on the concept of the effective volume fraction, ?_{eff} which depends on flow conditions. Indeed, in competition with particle interactions, hydrodynamic forces can modify (i) S, the number fraction of particles that all SUs contain, (ii) both SUs arrangements and their internal structure, especially the SU's compactness, \\varphi. As a structural variable, S is governed by a kinetic equation. Through the shear-dependent kinetic rates involved in the latter, the general solution S depends on ?, a dimensionless shear variable, leading to ?_{eff}(t, ?; \\varphi). The structural <span class="hlt">modelling</span> is achieved by introducing this expression of ?_{eff} into a well-established viscosity <span class="hlt">model</span> of hard sphere suspensions. Using the steady state solution of the kinetic equation, S_{eq}(? ), allows to <span class="hlt">model</span> non-Newtonian behaviors of complex fluids under steady shear conditions, as pseudo-plastic, plastic, dilatant ... ones. In this <span class="hlt">model</span>, the ratio of high shear to low shear limiting viscosities appears as a key variable. Different examples of application will be discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009JGRC..114.2016R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009JGRC..114.2016R"><span id="translatedtitle">Drift and mixing under the ocean surface <span class="hlt">revisited</span>: Stratified conditions and <span class="hlt">model</span>-data comparisons</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rascle, Nicolas; Ardhuin, Fabrice</p> <p>2009-02-01</p> <p>A one-dimensional <span class="hlt">model</span> of the ocean near-surface currents is presented. It includes the enhanced near-surface mixing due to the waves, the wave-induced Stokes drift, the Stokes-Coriolis (SC) effect, and the stratification. Near-surface current shears from this <span class="hlt">model</span> are compared with the shears of the quasi-Eulerian currents measured using a wave-following platform during the Shelf Mixed Layer Experiment (SMILE). It is shown that the downwind current shears observed during SMILE are well <span class="hlt">modeled</span>. However, the observed crosswind shears are in poor agreement with the <span class="hlt">model</span>. The Stokes-Coriolis (SC) term could qualitatively explain this misfit, but it is one order of magnitude too weak. The Ekman-Stokes spiral of the <span class="hlt">model</span> is compared with the spiral observed during the long time series of measurements Long Term Upper Ocean Study 3. The effects of stratification are taken into account. The mean velocity profiles of the <span class="hlt">model</span> closely agree with observations. However, there is no evidence of the SC effect on the shape of the observed current profile. The observed profile is found to be a consequence of the current rectification due to the time-varying stratification. The SC effect calculated from a numerical wave hindcast is weak but should have been observed. In fact, it is estimated that the wave-induced bias in the current measurements is larger than the SC effect. Finally, it is shown that the variation of surface drift with wave age, which was estimated to be small in unstratified conditions, is important in the presence of shallow mixed layers.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007JGRD..11213107R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007JGRD..11213107R"><span id="translatedtitle">Nuclear winter <span class="hlt">revisited</span> with a modern climate <span class="hlt">model</span> and current nuclear arsenals: Still catastrophic consequences</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Robock, Alan; Oman, Luke; Stenchikov, Georgiy L.</p> <p>2007-07-01</p> <p>Twenty years ago, the results of climate <span class="hlt">model</span> simulations of the response to smoke and dust from a massive nuclear exchange between the superpowers could be summarized as "nuclear winter," with rapid temperature, precipitation, and insolation drops at the surface that would threaten global agriculture for at least a year. The global nuclear arsenal has fallen by a factor of three since then, but there has been an expansion of the number of nuclear weapons states, with additional states trying to develop nuclear arsenals. We use a modern climate <span class="hlt">model</span> to reexamine the climate response to a range of nuclear wars, producing 50 and 150 Tg of smoke, using moderate and large portions of the current global arsenal, and find that there would be significant climatic responses to all the scenarios. This is the first time that an atmosphere-ocean general circulation <span class="hlt">model</span> has been used for such a simulation and the first time that 10-year simulations have been conducted. The response to the 150 Tg scenario can still be characterized as "nuclear winter," but both produce global catastrophic consequences. The changes are more long-lasting than previously thought, however, because the new <span class="hlt">model</span>, National Aeronautics and Space Administration Goddard Institute for Space Studies <span class="hlt">ModelE</span>, is able to represent the atmosphere up to 80 km, and simulates plume rise to the middle and upper stratosphere, producing a long aerosol lifetime. The indirect effects of nuclear weapons would have devastating consequences for the planet, and continued nuclear arsenal reductions will be needed before the threat of nuclear winter is removed from the Earth.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/15164227','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/15164227"><span id="translatedtitle">Large amplification in stage-structured <span class="hlt">models</span>: Arnol'd tongues <span class="hlt">revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Greenman, J V; Benton, T G</p> <p>2004-06-01</p> <p>The coexistence of periodic and point attractors has been confirmed for a range of stage-structured discrete time <span class="hlt">models</span>. The periodic attractor cycles have large amplitude, with the populations cycling between extremely low and surprisingly high values when compared to the equilibrium level. In this situation a stable state can be shocked by noise of sufficient strength into a state of high volatility. We found that the source of these large amplitude cycles are Arnol'd tongues, special regions of parameter space where the system exhibits periodic behaviour. Most of these tongues lie entirely in that part of parameter space where the system is unstable, but there are exceptions and these exceptions are the tongues that lead to attractor coexistence. Similarity in the geometry of Arnol'd tongues over the range of <span class="hlt">models</span> considered might suggest that this is a common feature of stage-structured <span class="hlt">models</span> but in the absence of proof this can only be a useful working hypothesis. The analysis shows that although large amplitude cycles might exist mathematically they might not be accessible biologically if biological constraints, such as non-negativity of population densities and vital rates, are imposed. Accessibility is found to be highly sensitive to <span class="hlt">model</span> structure even though the mathematical structure is not. This highlights the danger of drawing biological conclusions from particular <span class="hlt">models</span>. Having a comprehensive view of the different mechanisms by which periodic states can arise in families of discrete time <span class="hlt">models</span> is important in the debate on whether the causes of periodicity in particular ecological systems are intrinsic, environmental or trophic. This paper is a contribution to that continuing debate. PMID:15164227</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li class="active"><span>9</span></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_9 --> <div id="page_10" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="181"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..1511650R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..1511650R"><span id="translatedtitle"><span class="hlt">Revisiting</span> the radionuclide atmospheric dispersion event of the Chernobyl disaster - <span class="hlt">modelling</span> sensitivity and data assimilation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Roustan, Yelva; Duhanyan, Nora; Bocquet, Marc; Winiarek, Victor</p> <p>2013-04-01</p> <p>A sensitivity study of the numerical <span class="hlt">model</span>, as well as, an inverse <span class="hlt">modelling</span> approach applied to the atmospheric dispersion issues after the Chernobyl disaster are both presented in this paper. On the one hand, the robustness of the source term reconstruction through advanced data assimilation techniques was tested. On the other hand, the classical approaches for sensitivity analysis were enhanced by the use of an optimised forcing field which otherwise is known to be strongly uncertain. The POLYPHEMUS air quality system was used to perform the simulations of radionuclide dispersion. Activity concentrations in air and deposited to the ground of iodine-131, caesium-137 and caesium-134 were considered. The impact of the implemented parameterizations of the physical processes (dry and wet depositions, vertical turbulent diffusion), of the forcing fields (meteorology and source terms) and of the numerical configuration (horizontal resolution) were investigated for the sensitivity study of the <span class="hlt">model</span>. A four dimensional variational scheme (4D-Var) based on the approximate adjoint of the chemistry transport <span class="hlt">model</span> was used to invert the source term. The data assimilation is performed with measurements of activity concentrations in air extracted from the Radioactivity Environmental Monitoring (REM) database. For most of the investigated configurations (sensitivity study), the statistics to compare the <span class="hlt">model</span> results to the field measurements as regards the concentrations in air are clearly improved while using a reconstructed source term. As regards the ground deposited concentrations, an improvement can only be seen in case of satisfactorily <span class="hlt">modelled</span> episode. Through these studies, the source term and the meteorological fields are proved to have a major impact on the activity concentrations in air. These studies also reinforce the use of reconstructed source term instead of the usual estimated one. A more detailed parameterization of the deposition process seems also to be able to improve the simulation results. For deposited activities the results are more complex probably due to a strong sensitivity to some of the meteorological fields which remain quite uncertain.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011A%26A...532A.121H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011A%26A...532A.121H"><span id="translatedtitle">The Bosma effect <span class="hlt">revisited</span>. I. HI and stellar disc scaling <span class="hlt">models</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hessman, F. V.; Ziebart, M.</p> <p>2011-08-01</p> <p>Context. The observed proportionality between the centripetal contribution of the dynamically insignificant HI gas in the discs of spiral galaxies and the dominant contribution of dark matter (DM) - the "Bosma effect" - has been repeatedly mentioned in the literature but largely ignored. Since this phenomenology, if statistically significant, tells us something about the relationship between the visible baryonic and invisible DM, it is important to re-examine the reality of this effect using formal tests and more modern data. Aims: We have re-examined the evidence for the Bosma effect, either by scaling the contribution of the HI gas alone or by using both the observed stellar disc and HI gas as proxies. Methods: We have calculated Bosma effect <span class="hlt">models</span> for 17 galaxies in The HI Nearby Galaxy Survey data set. The results are compared with two <span class="hlt">models</span> for exotic cold DM: internally consistent cosmological Navarro-Frenk-White (NFW) <span class="hlt">models</span> with constrained compactness parameters, and "universal rotation curve" (URC) <span class="hlt">models</span> using fully unconstrained Burkert density profiles. Results: Fits to spiral galaxy rotation curves computed using just HI scaling are inadequate, despite the clear proportionality seen in the outer discs. The poor performance is obviously related to the prominent decrease in the HI surface density in regions of high stellar surface density, where HI has been converted into molecules and stars. The Bosma <span class="hlt">models</span> that partially correct for this physical effect using the stellar discs as additional proxies are statistically nearly as good as the URC <span class="hlt">models</span> and clearly better than the NFW ones. Conclusions: We confirm the correlation between the centripetal effects of DM and that of the interstellar medium of spiral galaxies. The efficacy of "maximal disc" <span class="hlt">models</span> is explained as the natural consequence of "classic" Bosma <span class="hlt">models</span> which include the stellar disc as a proxy in regions of reduced atomic gas. The perception that the Bosma effect could be due to the near-equality of the HI surface density and the projected mass density of a cold DM halo is incorrect, both theoretically and empirically. The standard explanation - that the effect reflects a statistical correlation between the visible and exotic DM - seems highly unlikely, given that the geometric forms and hence centripetal signatures of spherical halo and disc components are so different. A literal interpretation of the Bosma effect as being due to the presence of significant amounts of disc DM requires a median visible baryon to disc DM ratio of about 40%.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26328819','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26328819"><span id="translatedtitle">The Raspberry <span class="hlt">model</span> for hydrodynamic interactions <span class="hlt">revisited</span>. II. The effect of confinement.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>de Graaf, Joost; Peter, Toni; Fischer, Lukas P; Holm, Christian</p> <p>2015-08-28</p> <p>The so-called "raspberry" <span class="hlt">model</span> refers to the hybrid lattice-Boltzmann (LB) and Langevin molecular dynamics schemes for simulating the dynamics of suspensions of colloidal particles, originally developed by Lobaskin and Dnweg [New J. Phys. 6, 54 (2004)], wherein discrete surface points are used to achieve fluid-particle coupling. In this paper, we present a follow up to our study of the effectiveness of the raspberry <span class="hlt">model</span> in reproducing hydrodynamic interactions in the Stokes regime for spheres arranged in a simple-cubic crystal [Fischer et al., J. Chem. Phys. 143, 084107 (2015)]. Here, we consider the accuracy with which the raspberry <span class="hlt">model</span> is able to reproduce such interactions for particles confined between two parallel plates. To this end, we compare our LB simulation results to established theoretical expressions and finite-element calculations. We show that there is a discrepancy between the translational and rotational mobilities when only surface coupling points are used, as also found in Part I of our joint publication. We demonstrate that adding internal coupling points to the raspberry can be used to correct said discrepancy in confining geometries as well. Finally, we show that the raspberry <span class="hlt">model</span> accurately reproduces hydrodynamic interactions between a spherical colloid and planar walls up to roughly one LB lattice spacing. PMID:26328819</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Luxembourg&pg=3&id=EJ910601','ERIC'); return false;" href="http://eric.ed.gov/?q=Luxembourg&pg=3&id=EJ910601"><span id="translatedtitle">The Structure of Academic Self-Concepts <span class="hlt">Revisited</span>: The Nested Marsh/Shavelson <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Brunner, Martin; Keller, Ulrich; Dierendonck, Christophe; Reichert, Monique; Ugen, Sonja; Fischbach, Antoine; Martin, Romain</p> <p>2010-01-01</p> <p>The nested Marsh/Shavelson (NMS) <span class="hlt">model</span> integrates structural characteristics of academic self-concepts that have proved empirically incompatible in previous studies. Specifically, it conceives of academic self-concepts to be subject specific, strongly separated across domains, and hierarchically organized, with general academic self-concept at the…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=N--2-&pg=5&id=EJ1067659','ERIC'); return false;" href="http://eric.ed.gov/?q=N--2-&pg=5&id=EJ1067659"><span id="translatedtitle">The Reciprocal Effects <span class="hlt">Model</span> <span class="hlt">Revisited</span>: Extending Its Reach to Gifted Students Attending Academically Selective Schools</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Seaton, Marjorie; Marsh, Herbert W.; Parker, Philip D.; Craven, Rhonda G.; Yeung, Alexander S.</p> <p>2015-01-01</p> <p>The reciprocal effects <span class="hlt">model</span> (REM) predicts a reciprocal relation between academic self-concept and academic achievement, whereby prior academic self-concept is associated with future gains in achievement, and prior achievement is related to subsequent academic self-concept. Although research in this area has been extensive, there has been a…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Expansion&pg=5&id=EJ1022960','ERIC'); return false;" href="http://eric.ed.gov/?q=Expansion&pg=5&id=EJ1022960"><span id="translatedtitle">Social Mobility and Post-Compulsory Education: <span class="hlt">Revisiting</span> Boudon's <span class="hlt">Model</span> of Social Opportunity</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Thompson, Ron; Simmons, Robin</p> <p>2013-01-01</p> <p>This paper uses Raymond Boudon's <span class="hlt">model</span> of educational expansion to examine the relationship between education and social mobility, paying particular attention to post-compulsory education--an important site of social differentiation in England. The paper shows how Boudon focuses explicitly on the consequences of educational expansion, and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=vector+AND+psychology&pg=2&id=EJ890089','ERIC'); return false;" href="http://eric.ed.gov/?q=vector+AND+psychology&pg=2&id=EJ890089"><span id="translatedtitle">Holland in Iceland <span class="hlt">Revisited</span>: An Emic Approach to Evaluating U.S. Vocational Interest <span class="hlt">Models</span></span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Einarsdottir, Sif; Rounds, James; Su, Rong</p> <p>2010-01-01</p> <p>An emic approach was used to test the structural validity and applicability of Holland's (1997) RIASEC (Realistic, Investigative, Artistic, Social, Enterprising, Conventional) <span class="hlt">model</span> in Iceland. Archival data from the development of the Icelandic Interest Inventory (Einarsdottir & Rounds, 2007) were used in the present investigation. The data</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Frame+AND+Structure&pg=6&id=EJ933873','ERIC'); return false;" href="http://eric.ed.gov/?q=Frame+AND+Structure&pg=6&id=EJ933873"><span id="translatedtitle">The PANAS Structure <span class="hlt">Revisited</span>: On the Validity of a Bifactor <span class="hlt">Model</span> in Community and Forensic Samples</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Leue, Anja; Beauducel, Andre</p> <p>2011-01-01</p> <p>The Positive and Negative Affect Schedule (PANAS) is a widely used inventory for the assessment of affect in psychology and other applied sciences. Despite its popularity, the structure of the PANAS is still under debate. On the one hand, there is evidence of the traditional 2-factor <span class="hlt">model</span> with Positive Affect (PA) and Negative Affect (NA) as</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Nm&id=EJ910601','ERIC'); return false;" href="http://eric.ed.gov/?q=Nm&id=EJ910601"><span id="translatedtitle">The Structure of Academic Self-Concepts <span class="hlt">Revisited</span>: The Nested Marsh/Shavelson <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Brunner, Martin; Keller, Ulrich; Dierendonck, Christophe; Reichert, Monique; Ugen, Sonja; Fischbach, Antoine; Martin, Romain</p> <p>2010-01-01</p> <p>The nested Marsh/Shavelson (NMS) <span class="hlt">model</span> integrates structural characteristics of academic self-concepts that have proved empirically incompatible in previous studies. Specifically, it conceives of academic self-concepts to be subject specific, strongly separated across domains, and hierarchically organized, with general academic self-concept at the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26305153','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26305153"><span id="translatedtitle">Localization-Delocalization in Bridged Mixed-Valence Metal Clusters: Vibronic PKS <span class="hlt">Model</span> <span class="hlt">Revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Palii, A; Tsukerblat, B; Clemente-Juan, J M; Aldoshin, S M</p> <p>2015-09-24</p> <p>Here we describe a new vibronic <span class="hlt">model</span> of mixed valence (MV) dimer inspired by the conventional Piepho, Krausz, and Schatz (PKS) approach. We attempted to partially lift the main restriction of the PKS <span class="hlt">model</span> dealing with the vibronically independent moieties of a MV molecule. The refined version of the PKS <span class="hlt">model</span> in which the bridging ligands are included deals with the three main interactions: electron transfer (integral t0) related to the high-symmetric ligand configuration, on-site vibronic coupling (parameter ?) arising from the modulation of the crystal field on the metal sites by the breathing displacements of their nearest ligand surroundings, and intercenter vibronic coupling (parameter ?) describing the dependence of the electron transfer on ligand positions in the course of their breathing movement. We apply the modified <span class="hlt">model</span> to the analysis of the adiabatic potentials and electronic density distributions in the minima of their lower sheets for the cases of one-electron MV dimer with long and short bridges and for the two-electron MV dimer exhibiting a valence disproportionation effect. The inclusion of the intercenter interaction in addition to the conventional PKS coupling is shown to produce a strong effect on the degree of localization in MV dimers and, in particular, on the assignments to the Robin and Day classes and on the conditions of stabilization of valence disproportionated states in bielectron transfer systems. PMID:26305153</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015Icar..261..133K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015Icar..261..133K"><span id="translatedtitle">Sulfur in the early martian atmosphere <span class="hlt">revisited</span>: Experiments with a 3-D Global Climate <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kerber, Laura; Forget, François; Wordsworth, Robin</p> <p>2015-11-01</p> <p>Volcanic SO2 in the martian atmosphere has been invoked as a way to create a sustained or transient greenhouse during early martian history. Many <span class="hlt">modeling</span> studies have been performed to test the feasibility of this hypothesis, resulting in a range of conclusions, from highly feasible to highly improbable. In this study we perform a wide range of simulations using the 3-D Laboratoire de Météorologie Dynamique Generic Global Climate <span class="hlt">Model</span> (GCM) in order to place earlier results into context and to explore the sensitivity of <span class="hlt">model</span> outcomes to parameters such as SO2 mixing ratio, atmospheric H2O content, background atmospheric pressure, and aerosol size, abundance, and composition. We conclude that SO2 is incapable of creating a sustained greenhouse on early Mars, and that even in the absence of aerosols, local and daily temperatures rise above 273 K for only for limited periods with favorable background CO2 pressures. In the presence of even small amounts of aerosols, the surface is dramatically cooled for realistic aerosol sizes. Brief, mildly warm conditions require the co-occurrence of many improbable factors, while cooling is achieved for a wide range of <span class="hlt">model</span> parameters. Instead of causing warming, sulfur in the martian atmosphere may have caused substantial cooling, leading to the end of clement climate conditions on early Mars.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=psychiatry+AND+models&id=EJ885695','ERIC'); return false;" href="http://eric.ed.gov/?q=psychiatry+AND+models&id=EJ885695"><span id="translatedtitle">Curricular Adaptations in Inpatient Child Psychiatry for the 21st Century: The Flexner <span class="hlt">Model</span> <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Bell, Cathy K.; Guerrero, Anthony; Matsu, Courtenay; Takeshita, Junji; Haning, William; Schultz, Karen</p> <p>2010-01-01</p> <p>Objective: The authors describe curricular modifications created in response to the changing culture of medical education, health care systems, academic medicine, and generational differences. The authors propose a <span class="hlt">model</span> child psychiatry inpatient curriculum that is sustainable within a community teaching hospital in the 21st century. Methods: The</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26077396','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26077396"><span id="translatedtitle"><span class="hlt">Revisiting</span> the case for genetically engineered mouse <span class="hlt">models</span> in human myelodysplastic syndrome research.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhou, Ting; Kinney, Marsha C; Scott, Linda M; Zinkel, Sandra S; Rebel, Vivienne I</p> <p>2015-08-27</p> <p>Much-needed attention has been given of late to diseases specifically associated with an expanding elderly population. Myelodysplastic syndrome (MDS), a hematopoietic stem cell-based blood disease, is one of these. The lack of clear understanding of the molecular mechanisms underlying the pathogenesis of this disease has hampered the development of efficacious therapies, especially in the presence of comorbidities. Mouse <span class="hlt">models</span> could potentially provide new insights into this disease, although primary human MDS cells grow poorly in xenografted mice. This makes genetically engineered murine <span class="hlt">models</span> a more attractive proposition, although this approach is not without complications. In particular, it is unclear if or how myelodysplasia (abnormal blood cell morphology), a key MDS feature in humans, presents in murine cells. Here, we evaluate the histopathologic features of wild-type mice and 23 mouse <span class="hlt">models</span> with verified myelodysplasia. We find that certain features indicative of myelodysplasia in humans, such as Howell-Jolly bodies and low neutrophilic granularity, are commonplace in healthy mice, whereas other features are similarly abnormal in humans and mice. Quantitative hematopoietic parameters, such as blood cell counts, are required to distinguish between MDS and related diseases. We provide data that mouse <span class="hlt">models</span> of MDS can be genetically engineered and faithfully recapitulate human disease. PMID:26077396</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=sound+AND+frequencies+AND+measured&id=EJ924145','ERIC'); return false;" href="http://eric.ed.gov/?q=sound+AND+frequencies+AND+measured&id=EJ924145"><span id="translatedtitle"><span class="hlt">Revisiting</span> the Home Literacy <span class="hlt">Model</span> of Reading Development in an Orthographically Consistent Language</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Manolitsis, George; Georgiou, George K.; Parrila, Rauno</p> <p>2011-01-01</p> <p>We examined the applicability of the Home Literacy <span class="hlt">Model</span> in an orthographically transparent language (Greek). Seventy Greek children were followed from kindergarten until grade 4. In kindergarten they were tested in non-verbal intelligence, vocabulary, phonological sensitivity, rapid naming, and letter knowledge. The parents of the children also</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=738&id=EJ1067659','ERIC'); return false;" href="http://eric.ed.gov/?q=738&id=EJ1067659"><span id="translatedtitle">The Reciprocal Effects <span class="hlt">Model</span> <span class="hlt">Revisited</span>: Extending Its Reach to Gifted Students Attending Academically Selective Schools</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Seaton, Marjorie; Marsh, Herbert W.; Parker, Philip D.; Craven, Rhonda G.; Yeung, Alexander S.</p> <p>2015-01-01</p> <p>The reciprocal effects <span class="hlt">model</span> (REM) predicts a reciprocal relation between academic self-concept and academic achievement, whereby prior academic self-concept is associated with future gains in achievement, and prior achievement is related to subsequent academic self-concept. Although research in this area has been extensive, there has been a</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JChPh.143h4108D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JChPh.143h4108D"><span id="translatedtitle">The Raspberry <span class="hlt">model</span> for hydrodynamic interactions <span class="hlt">revisited</span>. II. The effect of confinement</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>de Graaf, Joost; Peter, Toni; Fischer, Lukas P.; Holm, Christian</p> <p>2015-08-01</p> <p>The so-called "raspberry" <span class="hlt">model</span> refers to the hybrid lattice-Boltzmann (LB) and Langevin molecular dynamics schemes for simulating the dynamics of suspensions of colloidal particles, originally developed by Lobaskin and Dünweg [New J. Phys. 6, 54 (2004)], wherein discrete surface points are used to achieve fluid-particle coupling. In this paper, we present a follow up to our study of the effectiveness of the raspberry <span class="hlt">model</span> in reproducing hydrodynamic interactions in the Stokes regime for spheres arranged in a simple-cubic crystal [Fischer et al., J. Chem. Phys. 143, 084107 (2015)]. Here, we consider the accuracy with which the raspberry <span class="hlt">model</span> is able to reproduce such interactions for particles confined between two parallel plates. To this end, we compare our LB simulation results to established theoretical expressions and finite-element calculations. We show that there is a discrepancy between the translational and rotational mobilities when only surface coupling points are used, as also found in Part I of our joint publication. We demonstrate that adding internal coupling points to the raspberry can be used to correct said discrepancy in confining geometries as well. Finally, we show that the raspberry <span class="hlt">model</span> accurately reproduces hydrodynamic interactions between a spherical colloid and planar walls up to roughly one LB lattice spacing.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=forensic+AND+psychology&pg=4&id=EJ933873','ERIC'); return false;" href="http://eric.ed.gov/?q=forensic+AND+psychology&pg=4&id=EJ933873"><span id="translatedtitle">The PANAS Structure <span class="hlt">Revisited</span>: On the Validity of a Bifactor <span class="hlt">Model</span> in Community and Forensic Samples</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Leue, Anja; Beauducel, Andre</p> <p>2011-01-01</p> <p>The Positive and Negative Affect Schedule (PANAS) is a widely used inventory for the assessment of affect in psychology and other applied sciences. Despite its popularity, the structure of the PANAS is still under debate. On the one hand, there is evidence of the traditional 2-factor <span class="hlt">model</span> with Positive Affect (PA) and Negative Affect (NA) as…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..1510824D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..1510824D"><span id="translatedtitle"><span class="hlt">Revisiting</span> "Nutrient Trapping" in global coupled biogeochemical Ocean Circulation <span class="hlt">Models</span>: Cause and remedy.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dietze, Heiner; Getzlaff, Julia; Lptien, Ulrike</p> <p>2013-04-01</p> <p>The eastern equatorial Pacific puts our understanding of the interactions between atmosphere, ocean, and pelagic biogeochemical cycling, as expressed in numerical <span class="hlt">models</span>, to the test. Among notorious and persistent problems are a spurious double-split ITCZ and a deficient representation of the "cold-tongue". Maybe less prominent is the problem of nutrient accumulation at depth, dubbed "nutrient trapping" by Najjar (1992). In contrast to previous work we argue that "nutrient trapping" is also a persistent problem that has an oxygen counterpart which retards <span class="hlt">model</span>-based estimates of denitrification. A fishing exercise (i.e. an analysis of more than 70 <span class="hlt">model</span> simulations), carried out to isolate the cause of the problem, indicates that a deficient representation of the equatorial Intermediate Current System (EICS) is associated with the problem, rather than a deficient representation of the Equatorial Undercurrent as previously thought. Further, we present a parameterization that mimics the effect of the (unresolved) EICS in an Earth System Climate <span class="hlt">Model</span> and discuss its effect on anticipated changes of denitrification in a warming climate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26571206','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26571206"><span id="translatedtitle"><span class="hlt">Re-visiting</span> crash-speed relationships: A new perspective in crash <span class="hlt">modelling</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Imprialou, Maria-Ioanna M; Quddus, Mohammed; Pitfield, David E; Lord, Dominique</p> <p>2016-01-01</p> <p>Although speed is considered to be one of the main crash contributory factors, research findings are inconsistent. Independent of the robustness of their statistical approaches, crash frequency <span class="hlt">models</span> typically employ crash data that are aggregated using spatial criteria (e.g., crash counts by link termed as a link-based approach). In this approach, the variability in crashes between links is explained by highly aggregated average measures that may be inappropriate, especially for time-varying variables such as speed and volume. This paper re-examines crash-speed relationships by creating a new crash data aggregation approach that enables improved representation of the road conditions just before crash occurrences. Crashes are aggregated according to the similarity of their pre-crash traffic and geometric conditions, forming an alternative crash count dataset termed as a condition-based approach. Crash-speed relationships are separately developed and compared for both approaches by employing the annual crashes that occurred on the Strategic Road Network of England in 2012. The datasets are <span class="hlt">modelled</span> by injury severity using multivariate Poisson lognormal regression, with multivariate spatial effects for the link-based <span class="hlt">model</span>, using a full Bayesian inference approach. The results of the condition-based approach show that high speeds trigger crash frequency. The outcome of the link-based <span class="hlt">model</span> is the opposite; suggesting that the speed-crash relationship is negative regardless of crash severity. The differences between the results imply that data aggregation is a crucial, yet so far overlooked, methodological element of crash data analyses that may have direct impact on the <span class="hlt">modelling</span> outcomes. PMID:26571206</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012WRR....4811527L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012WRR....4811527L"><span id="translatedtitle">Temporal moments <span class="hlt">revisited</span>: Why there is no better way for physically based <span class="hlt">model</span> reduction in time</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Leube, P. C.; Nowak, W.; Schneider, G.</p> <p>2012-11-01</p> <p>Many hydro(geo)logical problems are highly complex in space and time, coupled with scale issues, variability, and uncertainty. Especially time-dependent <span class="hlt">models</span> often consume enormous computational resources, but <span class="hlt">model</span> reduction techniques can alleviate this problem. Temporal moments (TM) offer an approach to reduce the time demands of transient hydro(geo)logical simulations. TM reduce transient governing equations to steady state and directly simulate the temporal characteristics of the system, if the equations are linear and coefficients are time independent. This is achieved by an integral transform, projecting the dynamic system response onto monomials in time. In comparison to classical approaches of <span class="hlt">model</span> reduction that involve orthogonal base functions, however, the monomials for TM are nonorthogonal, which might impair the quality and efficiency of <span class="hlt">model</span> reduction. Thus, we raise the question of whether there are more suitable temporal base functions than the monomials that lead to TM. In this work, we will derive theoretically that there is only a limited class of temporal base functions that can reduce hydro(geo)logical <span class="hlt">models</span>. By comparing those to TM we conclude that, in terms of gained efficiency versus maintained accuracy, TM are the best possible choice. While our theoretical results hold for all systems of linear partial or ordinary differential equations (PDEs, ODEs) with any order of space and time derivatives, we illustrate our study with an example of pumping tests in a confined aquifer. For that case, we demonstrate that two (four) TM are sufficient to represent more than 80% (90%) of the dynamic behavior, and that the information content strictly increases with increasing TM order.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_10 --> <div id="page_11" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="201"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25678683','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25678683"><span id="translatedtitle"><span class="hlt">Revisiting</span> a two-patch SIS <span class="hlt">model</span> with infection during transport.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Arino, Julien; Sun, Chengjun; Yang, Wei</p> <p>2016-03-01</p> <p>We incorporate parameter heterogeneity in a two-patch susceptible-infectious-susceptible (SIS) epidemic <span class="hlt">model</span> with infection during transport and prove that the disease-free and endemic equilibria are globally asymptotically stable when the basic reproduction number [Formula: see text] and [Formula: see text], respectively. We find that infection during transport increases the possibility that the disease persists in both patches and amplifies prevalence when disease is present. We then study the effect of a perfect unilateral exit screening programme. Finally, we compare numerically the effects of using different incidence functions for infection within and while travelling between patches, and find that using mass action incidence to <span class="hlt">model</span> infection during transport has the effect of maintaining disease prevalence at a higher level compared with when standard incidence is used. PMID:25678683</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1997NuPhB.489..679J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1997NuPhB.489..679J"><span id="translatedtitle">Three-dimensional 3-state Potts <span class="hlt">model</span> <span class="hlt">revisited</span> with new techniques</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Janke, Wolfhard; Villanova, Ramon</p> <p>1997-02-01</p> <p>We report a fairly detailed finite-size scaling analysis of the first-order phase transition in the three-dimensional 3-state Potts <span class="hlt">model</span> on cubic lattices with emphasis on recently introduced quantities whose infinite-volume extrapolations are governed only by exponentially small terms. In these quantities no asymptotic power series in the inverse volume are involved which complicate the finite-size scaling behaviour of standard observables related to the specific-heat maxima or Binder-parameter minima. Introduced initially for strong first-order phase transitions in q-state Potts <span class="hlt">models</span> with "large enough" q, the new techniques prove to be surprisingly accurate for a q value as small as 3. On the basis of the high-precision Monte Carlo data of Alves et al. [Phys. Rev. B 43 (1991) 5846], this leads to a refined estimate of ?t = 0.550 565(10) for the infinite-volume transition point.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..1513374H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..1513374H"><span id="translatedtitle">Climate classification <span class="hlt">revisited</span>: From Köppen to Trewartha for <span class="hlt">models</span> evaluation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Halenka, Tomas; Belda, Michal; Kalvova, Jaroslava; Holtanova, Eva</p> <p>2013-04-01</p> <p>The analysis of climate patterns can be performed for each climatic variable separately or the data can be aggregated using e.g. a kind of climate classification. These classifications usually correspond to vegetation distribution in the sense that each climate type is dominated by one vegetation zone or eco-region. This way climate classifications also represent a convenient tool for validation of climate <span class="hlt">models</span> and for the analysis of simulated future climate changes. Basic concepts are presented on global CRU data and the analysis is shown on CMIP5 family of GCM simulations. Different performance of individual GCMs can be seen, but with clear indication of some similarities given by the <span class="hlt">model</span> dependencies. This evaluation can provide first insight on the driving GCM performance in individual region for further downscaling. Furthemore, the preliminary analysis evaluating Euro-CORDEX simulations in terms of chmate types will be presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JSMTE..09..016B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JSMTE..09..016B"><span id="translatedtitle">Learning of couplings for random asymmetric kinetic Ising <span class="hlt">models</span> <span class="hlt">revisited</span>: random correlation matrices and learning curves</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bachschmid-Romano, Ludovica; Opper, Manfred</p> <p>2015-09-01</p> <p>We study analytically the performance of a recently proposed algorithm for learning the couplings of a random asymmetric kinetic Ising <span class="hlt">model</span> from finite length trajectories of the spin dynamics. Our analysis shows the importance of the nontrivial equal time correlations between spins induced by the dynamics for the speed of learning. These correlations become more important as the spin's stochasticity is decreased. We also analyse the deviation of the estimation error from asymptotic optimality.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005Icar..176..192C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005Icar..176..192C"><span id="translatedtitle">Direct Monte Carlo and multifluid <span class="hlt">modeling</span> of the circumnuclear dust coma. Spherical grain dynamics <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Crifo, J.-F.; Loukianov, G. A.; Rodionov, A. V.; Zakharov, V. V.</p> <p>2005-07-01</p> <p>This paper describes the first computations of dust distributions in the vicinity of an active cometary nucleus, using a multidimensional Direct Simulation Monte Carlo Method (DSMC). The physical <span class="hlt">model</span> is simplistic: spherical grains of a broad range of sizes are liberated by H 2O sublimation from a selection of nonrotating sunlit spherical nuclei, and submitted to the nucleus gravity, the gas drag, and the solar radiation pressure. The results are compared to those obtained by the previously described Dust Multi-Fluid Method (DMF) and demonstrate an excellent agreement in the regions where the DMF is usable. Most importantly, the DSMC allows the discovery of hitherto unsuspected dust coma properties in those cases which cannot be treated by the DMF. This leads to a thorough reconsideration of the properties of the near-nucleus dust dynamics. In particular, the results show that (1) none of the three forces considered here can be neglected a priori, in particular not the radiation pressure; (2) hitherto unsuspected new families of grain trajectories exist, for instance trajectories leading from the nightside surface to the dayside coma; (3) a wealth of balistic-like trajectories leading from one point of the surface to another point exist; on the dayside, such trajectories lead to the formation of "mini-volcanoes." The present <span class="hlt">model</span> and results are discussed carefully. It is shown that (1) the neglected forces (inertia associated with a nucleus rotation, solar tidal force) are, in general, not negligible everywhere, and (2) when allowing for these additional forces, a time-dependent <span class="hlt">model</span> will, in general, have to be used. The future steps of development of the <span class="hlt">model</span> are outlined.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014CliPa..10..697L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014CliPa..10..697L"><span id="translatedtitle">The faint young Sun problem <span class="hlt">revisited</span> with a 3-D climate-carbon <span class="hlt">model</span> - Part 1</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Le Hir, G.; Teitler, Y.; Fluteau, F.; Donnadieu, Y.; Philippot, P.</p> <p>2014-04-01</p> <p>During the Archaean, the Sun's luminosity was 18 to 25% lower than the present day. One-dimensional radiative convective <span class="hlt">models</span> (RCM) generally infer that high concentrations of greenhouse gases (CO2, CH4) are required to prevent the early Earth's surface temperature from dropping below the freezing point of liquid water and satisfying the faint young Sun paradox (FYSP, an Earth temperature at least as warm as today). Using a one-dimensional (1-D) <span class="hlt">model</span>, it was proposed in 2010 that the association of a reduced albedo and less reflective clouds may have been responsible for the maintenance of a warm climate during the Archaean without requiring high concentrations of atmospheric CO2 (pCO2). More recently, 3-D climate simulations have been performed using atmospheric general circulation <span class="hlt">models</span> (AGCM) and Earth system <span class="hlt">models</span> of intermediate complexity (EMIC). These studies were able to solve the FYSP through a large range of carbon dioxide concentrations, from 0.6 bar with an EMIC to several millibars with AGCMs. To better understand this wide range in pCO2, we investigated the early Earth climate using an atmospheric GCM coupled to a slab ocean. Our simulations include the ice-albedo feedback and specific Archaean climatic factors such as a faster Earth rotation rate, high atmospheric concentrations of CO2 and/or CH4, a reduced continental surface, a saltier ocean, and different cloudiness. We estimated full glaciation thresholds for the early Archaean and quantified positive radiative forcing required to solve the FYSP. We also demonstrated why RCM and EMIC tend to overestimate greenhouse gas concentrations required to avoid full glaciations or solve the FYSP. Carbon cycle-climate interplays and conditions for sustaining pCO2 will be discussed in a companion paper.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/1019205','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/1019205"><span id="translatedtitle">Simultaneous calibration of surface flow and baseflow simulations: a <span class="hlt">revisit</span> of the SWAT <span class="hlt">model</span> calibration framework</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Zhang, Xuesong; Srinivasan, Ragahvan; Arnold, J. G.; Izaurralde, Roberto C.; Bosch, David</p> <p>2011-04-21</p> <p>Accurate analysis of water flow pathways from rainfall to streams is critical for simulating water use, climate change impact, and contaminants transport. In this study, we developed a new scheme to simultaneously calibrate surface flow (SF) and baseflow (BF) simulations of soil and water assessment tool (SWAT) by combing evolutionary multi-objective optimization (EMO) and BF separation techniques. The application of this scheme demonstrated pronounced trade-off of SWATs performance on SF and BF simulations. The simulated major water fluxes and storages variables (e.g. soil moisture, evapotranspiration, and groundwater) using the multiple parameters from EMO span wide ranges. Uncertainty analysis was conducted by Bayesian <span class="hlt">model</span> averaging of the Pareto optimal solutions. The 90% confidence interval (CI) estimated using all streamflows substantially overestimate the uncertainty of low flows on BF days while underestimating the uncertainty of high flows on SF days. Despite using statistical criteria calculated based on streamflow for <span class="hlt">model</span> selection, it is important to conduct diagnostic analysis of the agreement of SWAT behaviour and actual watershed dynamics. The new calibration technique can serve as a useful tool to explore the tradeoff between SF and BF simulations and provide candidates for further diagnostic assessment and <span class="hlt">model</span> identification.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26039139','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26039139"><span id="translatedtitle">The Educational <span class="hlt">Model</span> of Private Colleges of Osteopathic Medicine: <span class="hlt">Revisited</span> for 2003-2013.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Cummings, Mark</p> <p>2015-12-01</p> <p>Trends in the development of new private colleges of osteopathic medicine (COMs) described by the author in 2003 have accelerated in the ensuing decade. During 2003 to 2013, 10 new COMs as well as 2 remote teaching sites and 4 new branch campuses at private institutions were accredited, leading to a 98% increase in the number of students enrolled in private COMs. The key features of the private COM educational <span class="hlt">model</span> during this period were a reliance on student tuition, the establishment of health professions education programs around the medical school, the expansion of class size, the creation of branch campuses and remote teaching sites, an environment that emphasizes teaching over research, and limited involvement in facilities providing clinical services to patients. There is institutional ownership of preclinical instruction, but clinical instruction occurs in affiliated hospitals and medical institutions where students are typically taught by volunteer and/or adjunct faculty.Between 2003 and 2013, this <span class="hlt">model</span> attracted smaller universities and organizations, which implemented the strategies of established private COMs in initiating new private COMs, branch campuses, and remote teaching sites. The new COMs have introduced changes to the osteopathic profession and private COM <span class="hlt">model</span> by expanding to new parts of the country and establishing the first for-profit medical school accredited in the United States in modern times. They have also increased pressure on the system of osteopathic graduate medical education, as the number of funded GME positions available to their graduates is less than the need. PMID:26039139</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=theories+AND+chemical+AND+changes&pg=4&id=EJ823781','ERIC'); return false;" href="http://eric.ed.gov/?q=theories+AND+chemical+AND+changes&pg=4&id=EJ823781"><span id="translatedtitle">The Rotating Morse-Pekeris Oscillator <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Zuniga, Jose; Bastida, Adolfo; Requena, Alberto</p> <p>2008-01-01</p> <p>The Morse-Pekeris oscillator <span class="hlt">model</span> for the calculation of the vibration-rotation energy levels of diatomic molecules is <span class="hlt">revisited</span>. This <span class="hlt">model</span> is based on the realization of a second-order exponential expansion of the centrifugal term about the minimum of the vibrational Morse oscillator and the subsequent analytical resolution of the resulting</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Vibration&pg=6&id=EJ823781','ERIC'); return false;" href="http://eric.ed.gov/?q=Vibration&pg=6&id=EJ823781"><span id="translatedtitle">The Rotating Morse-Pekeris Oscillator <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Zuniga, Jose; Bastida, Adolfo; Requena, Alberto</p> <p>2008-01-01</p> <p>The Morse-Pekeris oscillator <span class="hlt">model</span> for the calculation of the vibration-rotation energy levels of diatomic molecules is <span class="hlt">revisited</span>. This <span class="hlt">model</span> is based on the realization of a second-order exponential expansion of the centrifugal term about the minimum of the vibrational Morse oscillator and the subsequent analytical resolution of the resulting…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005AGUFM.V33D..03S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005AGUFM.V33D..03S"><span id="translatedtitle">Integrating Geodynamic and Petrological Numerical <span class="hlt">Models</span>; Mid-Ocean Ridge Flow Dynamics <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Smith, P. M.; Baker, L. J.; Hall, C. E.; Asimow, P. D.; Gurnis, M. C.</p> <p>2005-12-01</p> <p>We have adapted the adiabat_1ph front-end to the pHMELTS petrological <span class="hlt">model</span> and coupled it with a 2-D variable viscosity flow <span class="hlt">model</span>, such that energy and mass transfer are treated self-consistently. The combined <span class="hlt">model</span>, GyPSM, captures thermal and chemical controls on mantle dynamics and feedback between them. We have developed mid-ocean ridge and subduction zone versions (see Baker et al, this volume). MORs have been the most extensively studied igneous system but the lateral and vertical extent of melting is still uncertain and is generally represented as uniform upwelling in a triangular region extending to the base of the crust. How do processes such as cooling due to latent heat and the effect of volatiles on melting and rheology affect this geometry and the sensitivity to spreading rate, temperature and source heterogeneity? Most empirical parameterizations of melting invoked by geophysical <span class="hlt">models</span> make simplifying assumptions e.g. anhydrous source, batch melting. The approach used in pMELTS (Ghiorso et al, 2002), and the pHMELTS extension for water-undersaturated conditions, ensures that predicted melt productivity, chemistry and key thermodynamic quantities are internally consistent. By adding the flow <span class="hlt">model</span>, conservation of mass, momentum and energy can be simultaneously satisfied. At each incremental isentropic step, the equilibrium assemblage is found and then adjusted for melt extraction, diffusion and advection. Each of the thousands of pHMELTS calculations performed per iteration is associated with a particle and its path tracked. Scripts control program execution and exchange energetic and chemical information. The parallelized scheme is surprisingly robust and effective so long as ascending melt is not expected to react with the residue. Preliminary results suggest more rapid cooling and thickening of the lithosphere when melting is accounted for. The low-pressure viscosity is dominated by the cooling effect whereas the effect of water in olivine is noticeable at depth. Water promotes deep small degree melts that enhance the viscosity variation. The melting region has quite concave upper boundaries and seemingly does meet the base of the crust, at least for the chosen conditions, but the parameter space needs fuller investigation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013M%26PS...48..515S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013M%26PS...48..515S"><span id="translatedtitle">Ries crater and suevite <span class="hlt">revisited</span>Observations and <span class="hlt">modeling</span> Part I: Observations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Stffler, Dieter; Artemieva, Natalia A.; Wnnemann, Kai; Reimold, W. Uwe; Jacob, Juliane; Hansen, Birgit K.; Summerson, Iona A. T.</p> <p>2013-04-01</p> <p>We report results of an interdisciplinary project devoted to the 26 km-diameter Ries crater and to the genesis of suevite. Recent laboratory analyses of "crater suevite" occurring within the central crater basin and of "outer suevite" on top of the continuous ejecta blanket, as well as data accumulated during the past 50 years, are interpreted within the boundary conditions imposed by a comprehensive new effort to <span class="hlt">model</span> the crater formation and its ejecta deposits by computer code calculations (Artemieva et al. 2013). The properties of suevite are considered on all scales from megascopic to submicroscopic in the context of its geological setting. In a new approach, we reconstruct the minimum/maximum volumes of all allochthonous impact formations (108/116 km3), of suevite (14/22 km3), and the total volume of impact melt (4.9/8.0 km3) produced by the Ries impact event prior to erosion. These volumes are reasonably compatible with corresponding values obtained by numerical <span class="hlt">modeling</span>. Taking all data on modal composition, texture, chemistry, and shock metamorphism of suevite, and the results of <span class="hlt">modeling</span> into account, we arrive at a new empirical <span class="hlt">model</span> implying five main consecutive phases of crater formation and ejecta emplacement. Numerical <span class="hlt">modeling</span> indicates that only a very small fraction of suevite can be derived from the "primary ejecta plume," which is possibly represented by the fine-grained basal layer of outer suevite. The main mass of suevite was deposited from a "secondary plume" induced by an explosive reaction ("fuel-coolant interaction") of impact melt with water and volatile-rich sedimentary rocks within a clast-laden temporary melt pool. Both melt pool and plume appear to be heterogeneous in space and time. Outer suevite appears to be derived from an early formed, melt-rich and clast-poor plume region rich in strongly shocked components (melt ? clasts) and originating from an upper, more marginal zone of the melt pool. Crater suevite is obviously deposited from later formed, clast-rich and melt-poor plumes dominated by unshocked and weakly shocked clasts and derived from a deeper, central zone of the melt pool. Genetically, we distinguish between "primary suevite" which includes dike suevite, the lower sublayer of crater suevite, and possibly a basal layer of outer suevite, and "secondary suevite" represented by the massive upper sublayer of crater suevite and the main mass of outer suevite.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4278622','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4278622"><span id="translatedtitle">The Sugen 5416/hypoxia mouse <span class="hlt">model</span> of pulmonary hypertension <span class="hlt">revisited</span>: long-term follow-up</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Hansmann, Georg; Rose, Chase; Fernandez-Gonzalez, Angeles; Scheid, Annette; Mitsialis, S. Alex; Kourembanas, Stella</p> <p>2014-01-01</p> <p>Abstract The combination of a vascular endothelial growth factor receptor antagonist, Sugen 5416 (SU5416), and chronic hypoxia is known to cause pronounced pulmonary hypertension (PH) with angioobliterative lesions in rats and leads to exaggerated PH in mice as well. We sought to determine whether weekly SU5416 injections during 3 weeks of hypoxia leads to long-term development of angioobliterative lesions and sustained or progressive PH in mice. Male C57BL/6J mice were injected with SU5416 (SuHx) or vehicle (VehHx) weekly during 3 weeks of exposure to 10% oxygen. Echocardiographic and invasive measures of hemodynamics and pulmonary vascular morphometry were performed after the 3-week hypoxic exposure and after 10 weeks of recovery in normoxia. SuHx led to higher right ventricular (RV) systolic pressure and RV hypertrophy than VehHx after 3 weeks of hypoxia. Ten weeks after hypoxic exposure, RV systolic pressure decreased but remained elevated in SuHx mice compared with VehHx or normoxic control mice, but RV hypertrophy had resolved. After 3 weeks of hypoxia and 10 weeks of follow-up in normoxia, tricuspid annular plane systolic excursion was significantly decreased, indicating decreased systolic RV function. Very few angioobliterative lesions were found at the 10-week follow-up time point in SuHx mouse lungs. In conclusion, SU5416 combined with 3 weeks of hypoxia causes a more profound PH phenotype in mice than hypoxia alone. PH persists over 10 weeks of normoxic follow-up in SuHx mice, but significant angioobliterative lesions do not occur, and neither PH nor RV dysfunction worsens. The SuHx mouse <span class="hlt">model</span> is a useful adjunct to other PH <span class="hlt">models</span>, but the search will continue for a mouse <span class="hlt">model</span> that better recapitulates the human phenotype. PMID:25610598</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/23373426','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/23373426"><span id="translatedtitle">Electronegativity, charge transfer, crystal field strength, and the point charge <span class="hlt">model</span> <span class="hlt">revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Tanner, Peter A; Ning, Lixin</p> <p>2013-02-21</p> <p>Although the optical spectra of LnCl(6)(3-) systems are complex, only two crystal field parameters, B(40) and B(60), are required to <span class="hlt">model</span> the J-multiplet crystal field splittings in octahedral symmetry. It is found that these parameters exhibit R(-5) and R(-7) dependence, respectively, upon the ionic radius Ln(3+)(VI), but not upon the Ln-Cl distance. More generally, the crystal field strengths of LnX(6) systems (X = Br, Cl, F, O) exhibit linear relationships with ligand electronegativity, charge transfer energy, and fractional ionic character of the Ln-X bond. PMID:23373426</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1100784','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1100784"><span id="translatedtitle">Chayanov <span class="hlt">revisited</span>: A <span class="hlt">model</span> for the economics of complex kin units</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Hammel, E. A.</p> <p>2005-01-01</p> <p>Chayanov's <span class="hlt">model</span> of the peasant economy is based on autarkic nuclear family households. Expansion to the more complex households and kin groups common in peasant societies shows that the sharp changes Chayanov observed in the consumer/producer ratio over the domestic cycle are smoothed by the intergenerational structure of complex households and extended kin groups. This amelioration may be retarded by competition between constituent units. Understanding the dynamics of the developmental cycle and micropolitics of domestic groups is a useful correction to Chayanov's widely used formulation, especially in developing countries where complex kin structures are common. PMID:15867158</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PhLB..739..214H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PhLB..739..214H"><span id="translatedtitle">Symplectic deformations of integrable field theories and AdS/CFT</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hollowood, Timothy J.; Miramontes, J. Luis</p> <p>2014-12-01</p> <p>Relativistic integrable field theories like the <span class="hlt">sine-Gordon</span> equation have an infinite set of conserved charges. In a light-front formalism these conserved charges are closely related to the integrable modified KdV hierarchy at the classical level. The latter hierarchy admits a family of symplectic structures which we argue can be viewed as deformations of the relativistic <span class="hlt">sine-Gordon</span> symplectic structure. These deformed theories are integrable but no longer relativistic and the basic excitations of the theory, the solitons, have an interesting non-relativistic dispersion relation that in a certain limit becomes the dispersion relation of dyonic giant magnons of string theory in the AdS/CFT correspondence. We argue that the deformed classical theories can be lifted to quantum theories when the <span class="hlt">sine-Gordon</span> theory is embedded in a larger theory that describes the string world-sheet sigma <span class="hlt">model</span> in AdS5 S5.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015NuPhB.899...78N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015NuPhB.899...78N"><span id="translatedtitle">Josephson junction of non-Abelian superconductors and non-Abelian Josephson vortices</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nitta, Muneto</p> <p>2015-10-01</p> <p>A Josephson junction is made of two superconductors sandwiching an insulator, and a Josephson vortex is a magnetic vortex (flux tube) absorbed into the Josephson junction, whose dynamics can be described by the <span class="hlt">sine-Gordon</span> equation. In a field theory framework, a flexible Josephson junction was proposed, in which the Josephson junction is represented by a domain wall separating two condensations and a Josephson vortex is a <span class="hlt">sine-Gordon</span> soliton in the domain wall effective theory. In this paper, we propose a Josephson junction of non-Abelian color superconductors and show that a non-Abelian vortex (color magnetic flux tube) absorbed into it is a non-Abelian Josephson vortex represented as a non-Abelian <span class="hlt">sine-Gordon</span> soliton in the domain wall effective theory, that is the U (N) principal chiral <span class="hlt">model</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20040088889&hterms=actin&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dactin','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20040088889&hterms=actin&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dactin"><span id="translatedtitle">Columella cells <span class="hlt">revisited</span>: novel structures, novel properties, and a novel gravisensing <span class="hlt">model</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Staehelin, L. A.; Zheng, H. Q.; Yoder, T. L.; Smith, J. D.; Todd, P.</p> <p>2000-01-01</p> <p>A hundred years of research has not produced a clear understanding of the mechanism that transduces the energy associated with the sedimentation of starch-filled amyloplast statoliths in root cap columella cells into a growth response. Most <span class="hlt">models</span> postulate that the statoliths interact with microfilaments (MF) to transmit signals to the plasma membrane (or ER), or that sedimentation onto these organelles produces the signals. However, no direct evidence for statolith-MF links has been reported, and no asymmetric structures of columella cells have been identified that might explain how a root turned by 90 degrees knows which side is up. To address these and other questions, we have (1) quantitatively examined the effects of microgravity on the size, number, and spatial distribution of statoliths; (2) re-evaluated the ultrastructure of columella cells in high-pressure frozen/freeze-substituted roots; and (3) followed the sedimentation dynamics of statolith movements in reoriented root tips. The findings have led to the formulation of a new <span class="hlt">model</span> for the gravity-sensing apparatus of roots, which envisages the cytoplasm pervaded by an actin-based cytoskeletal network. This network is denser in the ER-devoid central region of the cell than in the ER-rich cell cortex and is coupled to receptors in the plasma membrane. Statolith sedimentation is postulated to disrupt the network and its links to receptors in some regions of the cell cortex, while allowing them to reform in other regions and thereby produce a directional signal.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhRvB..93h5108M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhRvB..93h5108M"><span id="translatedtitle">Spectral function of the Tomonaga-Luttinger <span class="hlt">model</span> <span class="hlt">revisited</span>: Power laws and universality</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Markhof, L.; Meden, V.</p> <p>2016-02-01</p> <p>We reinvestigate the momentum-resolved single-particle spectral function of the Tomonaga-Luttinger <span class="hlt">model</span>. In particular, we focus on the role of the momentum dependence of the two-particle interaction V (q ) . Usually, V (q ) is assumed to be a constant and integrals are regularized in the ultraviolet "by hand" employing an ad hoc procedure. As the momentum dependence of the interaction is irrelevant in the renormalization group sense, this does not affect the universal low-energy properties of the <span class="hlt">model</span>, e.g., exponents of power laws, if all energy scales are sent to zero. If, however, the momentum k is fixed away from the Fermi momentum kF, with |k - kF| setting a nonvanishing energy scale, the details of V (q ) start to matter. We provide strong evidence that any curvature of the two-particle interaction at small transferred momentum q destroys power-law scaling of the momentum-resolved spectral function as a function of energy. Even for |k - kF| much smaller than the momentum-space range of the interaction the spectral line shape depends on the details of V (q ) . The significance of our results for universality in the Luttinger liquid sense, for experiments on quasi-one-dimensional metals, and for recent results on the spectral function of one-dimensional correlated systems taking effects of the curvature of the single-particle dispersion into account ("nonlinear LL phenomenology") is discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/799014','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/799014"><span id="translatedtitle">Precision Measurements and Fermion Geography in the Randall-Sundrum <span class="hlt">Model</span> <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Petriello, Frank J</p> <p>2002-03-08</p> <p>We re-examine the implications of allowing fermion fields to propagate in the five-dimensional bulk of the Randall-Sundrum (RS) localized gravity <span class="hlt">model</span>. We find that the large mixing between the Standard <span class="hlt">Model</span> top quark and its Kaluza Klein excitations restricts the fundamental RS scale to lie above 100 TeV. To circumvent this difficulty we propose a ''mixed'' scenario which localizes the third generation fermions on the TeV brane and allows the lighter generations to propagate in the full five-dimensional bulk. We show that this construction naturally reproduces the observed m{sub c}/m{sub t} and m{sub s}/m{sub b} hierarchies. We explore the signatures of this scenario in precision measurements and future high energy experiments. We find that the same region of parameter space that addresses the hierarchies of fermion Yukawa couplings also permits a Higgs boson with a mass of 500 GeV, and remains otherwise invisible at the LHC; however, the entire parameter region consistent with the electroweak precision data is testable at future linear colliders. We briefly discuss possible constraints on this scenario arising from flavor changing neutral currents.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_11 --> <div id="page_12" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="221"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011NW.....98..837O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011NW.....98..837O"><span id="translatedtitle">Parker's sneak-guard <span class="hlt">model</span> <span class="hlt">revisited</span>: why do reproductively parasitic males heavily invest in testes?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ota, Kazutaka; Kohda, Masanori; Hori, Michio; Sato, Tetsu</p> <p>2011-10-01</p> <p>Alternative reproductive tactics are widespread in males and may cause intraspecific differences in testes investment. Parker's sneak-guard <span class="hlt">model</span> predicts that sneaker males, who mate under sperm competition risk, invest in testes relatively more than bourgeois conspecifics that have lower risk. Given that sneakers are much smaller than bourgeois males, sneakers may increase testes investment to overcome their limited sperm productivity because of their small body sizes. In this study, we examined the mechanism that mediates differential testes investment across tactics in the Lake Tanganyika cichlid fish Lamprologus callipterus. In the Rumonge population of Burundi, bourgeois males are small compared with those in other populations and have a body size close to sneaky dwarf males. Therefore, if differences in relative testis investment depend on sperm competition, the rank order of relative testis investment should be dwarf males > bourgeois males in Rumonge = bourgeois males in the other populations. If differences in relative testis investment depend on body size, the rank order of relative testes investment should be dwarf males > bourgeois males in Rumonge > bourgeois males in the other populations. Comparisons of relative testis investment among the three male groups supported the role of sperm competition, as predicted by the sneak-guard <span class="hlt">model</span>. Nevertheless, the effects of absolute body size on testes investment should be considered to understand the mechanisms underlying intraspecific variation in testes investment caused by alternative reproductive tactics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3166726','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3166726"><span id="translatedtitle">Deconvolution-Based CT and MR Brain Perfusion Measurement: Theoretical <span class="hlt">Model</span> <span class="hlt">Revisited</span> and Practical Implementation Details</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Fieselmann, Andreas; Kowarschik, Markus; Ganguly, Arundhuti; Hornegger, Joachim; Fahrig, Rebecca</p> <p>2011-01-01</p> <p>Deconvolution-based analysis of CT and MR brain perfusion data is widely used in clinical practice and it is still a topic of ongoing research activities. In this paper, we present a comprehensive derivation and explanation of the underlying physiological <span class="hlt">model</span> for intravascular tracer systems. We also discuss practical details that are needed to properly implement algorithms for perfusion analysis. Our description of the practical computer implementation is focused on the most frequently employed algebraic deconvolution methods based on the singular value decomposition. In particular, we further discuss the need for regularization in order to obtain physiologically reasonable results. We include an overview of relevant preprocessing steps and provide numerous references to the literature. We cover both CT and MR brain perfusion imaging in this paper because they share many common aspects. The combination of both the theoretical as well as the practical aspects of perfusion analysis explicitly emphasizes the simplifications to the underlying physiological <span class="hlt">model</span> that are necessary in order to apply it to measured data acquired with current CT and MR scanners. PMID:21904538</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013BoLMe.147..301G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013BoLMe.147..301G"><span id="translatedtitle">Urban Morphology Influence on Urban Albedo: A <span class="hlt">Revisit</span> with the S olene <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Groleau, Dominique; Mestayer, Patrice G.</p> <p>2013-05-01</p> <p>This heuristic study of the urban morphology influence on urban albedo is based on some 3,500 simulations with the S olene <span class="hlt">model</span>. The studied configurations include square blocks in regular and staggered rows, rectangular blocks with different street widths, cross-shaped blocks, infinite street canyons and several actual districts in Marseilles, Toulouse and Nantes, France. The scanned variables are plan density, facade density, building height, layout orientation, latitude, date and time of the day. The sky-view factors of the ground and canopy surfaces are also considered. This study demonstrates the significance of the facade density, in addition to the built plan density, as the explanatory geometrical factor to characterize the urban morphology, rather than building height. On the basis of these albedo calculations the puzzling results of Kondo et al. (Boundary-Layer Meteorol 100:225-242, 2001) for the influence of building height are explained, and the plan density influence is quantitatively assessed. It is shown that the albedo relationship with plan and facade densities obtained with the regular square plot configuration may be considered as a reference for all other configurations, with the exception of the infinite street canyon that shows systematic differences for the lower plan densities. The curves representing this empirical relationship may be used as a sort of abacus for all other geometries while an approximate simple mathematical <span class="hlt">model</span> is proposed, as well as relationships between the albedo and sky-view factors.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009ApJ...707..218V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009ApJ...707..218V"><span id="translatedtitle">Dark Matter Halos and Evolution of Bars in Disk Galaxies: Collisionless <span class="hlt">Models</span> <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Villa-Vargas, Jorge; Shlosman, Isaac; Heller, Clayton</p> <p>2009-12-01</p> <p>We construct and evolve three one-parameter families and one two-parameter family of steady-state <span class="hlt">models</span> of stellar disks embedded in live dark matter (DM) halos in order to study the dynamical and secular phases of bar evolution. These <span class="hlt">models</span> are tested against those published in the literature in order to extend them and to include the gaseous component in the follow-up paper. Specifically, we are interested in the angular momentum, J, redistribution in the disk-halo system during these two evolutionary phases without distinguishing between the resonant and non-resonant effects. We confirm the previous results and quantify for the first time the dual role that the DM halos play in the bar evolution: more centrally concentrated halos dilute the dynamical processes of the initial bar growth, such as the spontaneous bar instability and the vertical buckling instability, and slow down the J transfer, while facilitating it in the secular phase. The rate of J transfer in the disk and the halo is followed up in order to identify sites and times of peak activity in J emission and absorption. Within the corotation radius, R cr, the disk J remains nearly constant in time, as long as R cr stays within the diska sign that the lost angular momentum to the outer disk and the halo is being compensated by an influx of fresh J due to the outward motion of R cr. We demonstrate that this is feasible as long as the bar slowdown dominates the loss of J inside R cr. Next, we find that in some <span class="hlt">models</span> the bar pattern speed stalls for prolonged time periods, i.e., the bar exhibits a constant rate of tumbling when R cr is located outside the disk. This phenomenon appears concurrent with the near absence of J transfer between the disk and the halo, and is associated with the halo emitting J at the corotation resonance and absorbing it at the inner Lindblad resonance. Furthermore, we confirm that stellar bars generally display the corotation-to-bar size ratios in the range of ~1-1.4, but only between the times of the first buckling and R cr leaving the disk. Hence, the corotation-to-disk size ratio emerges as an important dynamic discriminator between various stages of barred disk evolution. Finally, we analyze a number of correlations between the basic parameters of a barred disk and a halo, some already reported in the literature and some new.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21389317','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21389317"><span id="translatedtitle">DARK MATTER HALOS AND EVOLUTION OF BARS IN DISK GALAXIES: COLLISIONLESS <span class="hlt">MODELS</span> <span class="hlt">REVISITED</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Villa-Vargas, Jorge; Shlosman, Isaac; Heller, Clayton</p> <p>2009-12-10</p> <p>We construct and evolve three one-parameter families and one two-parameter family of steady-state <span class="hlt">models</span> of stellar disks embedded in live dark matter (DM) halos in order to study the dynamical and secular phases of bar evolution. These <span class="hlt">models</span> are tested against those published in the literature in order to extend them and to include the gaseous component in the follow-up paper. Specifically, we are interested in the angular momentum, J, redistribution in the disk-halo system during these two evolutionary phases without distinguishing between the resonant and non-resonant effects. We confirm the previous results and quantify for the first time the dual role that the DM halos play in the bar evolution: more centrally concentrated halos dilute the dynamical processes of the initial bar growth, such as the spontaneous bar instability and the vertical buckling instability, and slow down the J transfer, while facilitating it in the secular phase. The rate of J transfer in the disk and the halo is followed up in order to identify sites and times of peak activity in J emission and absorption. Within the corotation radius, R {sub cr}, the disk J remains nearly constant in time, as long as R {sub cr} stays within the disk-a sign that the lost angular momentum to the outer disk and the halo is being compensated by an influx of fresh J due to the outward motion of R {sub cr}. We demonstrate that this is feasible as long as the bar slowdown dominates the loss of J inside R {sub cr}. Next, we find that in some <span class="hlt">models</span> the bar pattern speed stalls for prolonged time periods, i.e., the bar exhibits a constant rate of tumbling when R {sub cr} is located outside the disk. This phenomenon appears concurrent with the near absence of J transfer between the disk and the halo, and is associated with the halo emitting J at the corotation resonance and absorbing it at the inner Lindblad resonance. Furthermore, we confirm that stellar bars generally display the corotation-to-bar size ratios in the range of approx1-1.4, but only between the times of the first buckling and R {sub cr} leaving the disk. Hence, the corotation-to-disk size ratio emerges as an important dynamic discriminator between various stages of barred disk evolution. Finally, we analyze a number of correlations between the basic parameters of a barred disk and a halo, some already reported in the literature and some new.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014LaPhy..24l5502A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014LaPhy..24l5502A"><span id="translatedtitle"><span class="hlt">Revisiting</span> the capture velocity of a cesium magneto-optical trap: <span class="hlt">model</span>, simulation and experiment</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Anwar, Muhammad; Magalhes, Daniel V.; Mller, Stella T.; Faisal, Muhammad; Nawaz, Muhammad; Ahmed, Mushtaq</p> <p>2014-12-01</p> <p>In this work, we have explored ab initio the capture process in a magneto-optical trap by theory, simulation and experiment. We measured the capture velocity vc of a cesium vapor cell magneto-optical trap (VCMOT) from its capture rate R and developed an exact <span class="hlt">model</span> for the capture rate of a VCMOT in terms of its capture velocity, background density and trap laser beam diameter. We measured the capture velocity of a cesium VCMOT for various trap laser intensities and magnetic field gradients. We observed that the capture velocity is a damping force as well as a restoring force phenomenon. We supported our findings by performing simulations for single atom trajectories in a 1D cesium MOT. Finally, we concluded that two MOTs can have the same capture velocities but very different capture rates, thereby revealing that these are two fundamentally different characteristics of the MOT.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22255185','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22255185"><span id="translatedtitle"><span class="hlt">Revisiting</span> density functionals for the primitive <span class="hlt">model</span> of electric double layers</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Jiang, Jian; Department of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029 ; Cao, Dapeng E-mail: doug@chem.byu.edu; Henderson, Douglas E-mail: doug@chem.byu.edu; Wu, Jianzhong E-mail: doug@chem.byu.edu</p> <p>2014-01-28</p> <p>Density functional theory (DFT) calculations are typically based on approximate functionals that link the free energy of a multi-body system of interest with the underlying one-body density distributions. Whereas good performance is often proclaimed for new developments, it is difficult to vindicate the theoretical merits relative to alternative versions without extensive comparison with the numerical results from molecular simulations. Besides, approximate functionals may defy statistical-mechanical sum rules and result in thermodynamic inconsistency. Here we compare systematically several versions of density functionals for ionic distributions near a charged surface using the primitive <span class="hlt">model</span> of electric double layers. We find that the theoretical performance is sensitive not only to the specific forms of the density functional but also to the range of parameter space and the precise properties under consideration. In general, incorporation of the thermodynamic sum rule into the DFT calculations shows significant improvements for both electrochemical properties and ionic distributions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3995688','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3995688"><span id="translatedtitle">Intuitive Logic <span class="hlt">Revisited</span>: New Data and a Bayesian Mixed <span class="hlt">Model</span> Meta-Analysis</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Singmann, Henrik; Klauer, Karl Christoph; Kellen, David</p> <p>2014-01-01</p> <p>Recent research on syllogistic reasoning suggests that the logical status (valid vs. invalid) of even difficult syllogisms can be intuitively detected via differences in conceptual fluency between logically valid and invalid syllogisms when participants are asked to rate how much they like a conclusion following from a syllogism (Morsanyi & Handley, 2012). These claims of an intuitive logic are at odds with most theories on syllogistic reasoning which posit that detecting the logical status of difficult syllogisms requires effortful and deliberate cognitive processes. We present new data replicating the effects reported by Morsanyi and Handley, but show that this effect is eliminated when controlling for a possible confound in terms of conclusion content. Additionally, we reanalyze three studies () without this confound with a Bayesian mixed <span class="hlt">model</span> meta-analysis (i.e., controlling for participant and item effects) which provides evidence for the null-hypothesis and against Morsanyi and Handley's claim. PMID:24755777</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007PhRvE..76a1104S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007PhRvE..76a1104S"><span id="translatedtitle">Ehrenfest urn <span class="hlt">revisited</span>: Playing the game on a realistic fluid <span class="hlt">model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Scalas, Enrico; Martin, Edgar; Germano, Guido</p> <p>2007-07-01</p> <p>The Ehrenfest urn process, also known as the dogs and fleas <span class="hlt">model</span>, is realistically simulated by molecular dynamics of the Lennard-Jones fluid. The key variable is ?z i.e., the absolute value of the difference between the number of particles in one half of the simulation box and in the other half. This is a pure-jump stochastic process induced, under coarse graining, by the deterministic time evolution of the atomic coordinates. We discuss the Markov hypothesis by analyzing the statistical properties of the jumps and the waiting times between the jumps. In the limit of a vanishing integration time step, the distribution of waiting times becomes closer to an exponential and, therefore, the continuous-time jump stochastic process is Markovian. The random variable ?z behaves as a Markov chain and, in the gas phase, the observed transition probabilities follow the predictions of the Ehrenfest theory.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015IREdu..61...79J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015IREdu..61...79J"><span id="translatedtitle">Pathways from adult education to well-being: The Tuijnman <span class="hlt">model</span> <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jenkins, Andrew; Wiggins, Richard D.</p> <p>2015-02-01</p> <p>There is a growing interest among researchers and policy-makers in the influence of adult learning on a range of outcomes, notably health and well-being. Much of the research to date has tended to focus on younger adults and the immediate benefits of course participation. The longer-term outcomes, such as the potential of accumulated learning experience for enriching later life, have been neglected. The study presented in this article adopts a lifecourse approach to participation in learning and the potential benefits of learning. The authors concentrate on adult education in mid-life, that is between the ages of 33 and 50, as the measure of learning participation. Their research draws upon previous work conducted by Albert Tuijnman which used Swedish data and which was published a quarter of a century ago in the pages of the International Review of Education. The authors of this paper seek to replicate and extend his pioneering work, using data from the National Child Development Study (NCDS), a large-scale survey containing information on all those born in Britain in one week in 1958. Follow-up data were collected at various points in childhood and adulthood, most recently when the cohort reached the age of 50, thus enabling insights into long-term developments. The authors analyse well-being at age 50 as an outcome in structural equation <span class="hlt">models</span> (SEM). This approach helps to understand the pathways through which adult education has an impact on well-being. The estimated <span class="hlt">models</span> show how adult education in mid-life has an influence on the type and quality of jobs which are accessible to individuals, and how this in turn can contribute to higher well-being at age 50.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70009721','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70009721"><span id="translatedtitle"><span class="hlt">Revisiting</span> classic water erosion <span class="hlt">models</span> in drylands: The strong impact of biological soil crusts</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Bowker, M.A.; Belnap, J.; Bala, Chaudhary V.; Johnson, N.C.</p> <p>2008-01-01</p> <p>Soil erosion and subsequent degradation has been a contributor to societal collapse in the past and is one of the major expressions of desertification in arid regions. The revised universal soil loss equation (RUSLE) <span class="hlt">models</span> soil lost to water erosion as a function of climate erosivity (the degree to which rainfall can result in erosion), topography, soil erodibility, and land use/management. The soil erodibility factor (K) is primarily based upon inherent soil properties (those which change slowly or not at all) such as soil texture and organic matter content, while the cover/management factor (C) is based on several parameters including biological soil crust (BSC) cover. We examined the effect of two more precise indicators of BSC development, chlorophyll a and exopolysaccharides (EPS), upon soil stability, which is closely inversely related to soil loss in an erosion event. To examine the relative influence of these elements of the C factor to the K factor, we conducted our investigation across eight strongly differing soils in the 0.8 million ha Grand Staircase-Escalante National Monument. We found that within every soil group, chlorophyll a was a moderate to excellent predictor of soil stability (R2 = 0.21-0.75), and consistently better than EPS. Using a simple structural equation <span class="hlt">model</span>, we explained over half of the variance in soil stability and determined that the direct effect of chlorophyll a was 3?? more important than soil group in determining soil stability. Our results suggest that, holding the intensity of erosive forces constant, the acceleration or reduction of soil erosion in arid landscapes will primarily be an outcome of management practices. This is because the factor which is most influential to soil erosion, BSC development, is also among the most manageable, implying that water erosion in drylands has a solution. ?? 2008 Elsevier Ltd.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016MNRAS.456.1837S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016MNRAS.456.1837S"><span id="translatedtitle"><span class="hlt">Revisiting</span> the ultraluminous supersoft source in M 101: an optically thick outflow <span class="hlt">model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Soria, Roberto; Kong, Albert</p> <p>2016-02-01</p> <p>The M 101 galaxy contains the best-known example of an ultraluminous supersoft source (ULS), dominated by a thermal component at kT ≈ 0.1 keV. The origin of the thermal component and the relation between ULSs and standard (broad-band spectrum) ultraluminous X-ray sources are still controversial. We re-examined the X-ray spectral and timing properties of the M 101 ULS using archival Chandra and XMM-Newton observations. We show that the X-ray time-variability and spectral properties are inconsistent with standard-disc emission. The characteristic radius Rbb of the thermal emitter varies from epoch to epoch between ≈10 000 and ≈100 000 km; the colour temperature kTbb varies between ≈50 and ≈140 eV and the two quantities scale approximately as R_bb ∝ T_bb^{-2}. In addition to the smooth continuum, we also find (at some epochs) spectral residuals well fitted with thermal-plasma <span class="hlt">models</span> and absorption edges: we interpret this as evidence that we are looking at a clumpy, multitemperature outflow. We suggest that at sufficiently high accretion rates and inclination angles, the supercritical, radiatively driven outflow becomes effectively optically thick and completely thermalizes the harder X-ray photons from the inner part of the inflow, removing the hard spectral tail. We develop a simple, spherically symmetric outflow <span class="hlt">model</span> and show that it is consistent with the observed temperatures, radii and luminosities. A larger, cooler photosphere shifts the emission peak into the far-UV and makes the source dimmer in X-rays but possibly ultraluminous in the UV. We compare our results and interpretation with those of Liu et al.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EPSC....8..528K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EPSC....8..528K"><span id="translatedtitle">Sulfur in the Early Martian Atmosphere <span class="hlt">Revisited</span>: Experiments with a 3-D Global Climate <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kerber, L.; Forget, F.; Wordsworth, R.</p> <p>2013-09-01</p> <p>Data returned from the surface of Mars during the 1970s revealed intriguing geological evidence for a warmer and wetter early martian climate. Dendritic valley networks were discovered by Mariner 9 on ancient Noachian terrain [1], indicating that liquid water had flowed across the surface in the distant past. Since this time, geological investigations into early Martian history have attempted to ascertain the nature and level of activity of the early Martian hydrological cycle [e.g. 2-5] while atmospheric <span class="hlt">modeling</span> efforts have focused on how the atmosphere could be warmed to temperatures great enough to sustain such activity [see 6-7 for reviews]. Geological and spectroscopic investigations have refined the history and chronology of Noachian Mars over time, and circulation of liquid water has been invoked to explain several spatially and temporally distinct morphological and chemical signatures found in the geological record. Detections of iron and magnesium-rich clays are widespread in the oldest Martian terrains, suggesting a period of pH-neutral aqueous alteration [e.g., 8]. Valley network incision also took place during the Noachian period [9]. Some chains of river valleys and craters lakes extend for thousands of kilometers, suggesting temperatures at least clement enough for sustained ice-covered flow [3,10]. The commencement of valley network incision is not well constrained, but the period of Mg/Fe clay formation appears to have ended before the termination of valley network formation, as the visible fluvial systems appear to have remobilized existing clays rather than forming them [5,8]. There is also evidence that the cessation of valley network formation was abrupt [11]. Towards the end of the Noachian, erosion rates appear to have been significantly higher than during subsequent periods, a process that has also been attributed to aqueous processes [12]. A period of sulfate formation followed, likely characterized by acidic, evaporitic playa environments [8]. A successful working <span class="hlt">model</span> for the early Martian atmosphere and hydrosphere must be able not only to produce conditions suitable for liquid water at the surface, but also to explain how the nature of this aqueous activity changed over time and eventually diminished. There are two major end-member hypotheses: first, that early Mars was wet and warm, with a sustained greenhouse that made it possible for liquid water to be stable on the surface for extended periods [e.g., 2, 12-14], and second, that early Mars was generally cold, and that most of the aqueous alteration took place underground [3,5] or during transient warm periods tied to impact cratering [15], or volcanism [16]. In both of these scenarios it is generally agreed that in order to make valley networks and sulfate deposits, a hydrological cycle is needed which is able to recycle water from the lowlands back to the highlands (i.e., the one-time emptying of a regional aquifer would not be sufficient to create the observed features) [4,17]. This would require some precipitation to fall on the southern highlands, either flowing overland or filtering into groundwater aquifers. In both cases, volcanic gases (especially SO2) have been suggested as a possible way of creating either a sustained or transient greenhouse. Several researchers have tested the addition of SO2 to climate <span class="hlt">models</span> in order to assess whether it would provide an adequate amount of greenhouse warming to allow liquid water to flow across the surface [18-21], with differing results. Postawko and Kuhn [18] found a warming effect of 14 K in a 0.1 bar atmosphere with an SO2 abundance of 1000 ppm. Johnson et al. [20] used a 3-D global circulation <span class="hlt">model</span> and found a warming of 15-25 K for 245 ppm of SO2 in a dry 0.5 bar atmosphere. Tian et al. [21] used a 1-D <span class="hlt">model</span> to explore a wide range of SO2 mixing values and CO2 partial pressures, finding a warming of around ~25 K for 100 ppm in a 0.5 bar atmosphere with a fully saturated troposphere (~40 K for a 1 bar atmosphere). These authors also included the effect of sulfate aerosol particles, which caused a dramatic cooling effect which more than canceled the warming caused by the SO2 gas [21]. Here we reconsider the efficacy of a sulfurinduced greenhouse in early Noachian history using the LMD (Laboratoire de Météorologie Dynamique) 3-D Generic Climate <span class="hlt">Model</span> (LMD-GCM), exploring the effects of SO2, H2S, and sulfate and S8 aerosols on the surface temperature, and the expected photochemical lifetime of SO2 in the atmosphere.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004JAtS...61..224V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004JAtS...61..224V"><span id="translatedtitle">Inertia Gravity Wave Generation by Balanced Motion: <span class="hlt">Revisiting</span> the Lorenz Krishnamurthy <span class="hlt">Model</span>.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vanneste, J.</p> <p>2004-01-01</p> <p>The spontaneous generation of inertia gravity waves by balanced motion at low Rossby number is examined using Lorenz's five-component <span class="hlt">model</span>. The mostly numerical analysis by Lorenz and Krishnamurthy of a particular (homoclinic) balanced solution is complemented here by an asymptotic analysis. An exponential asymptotic technique provides an estimate for the amplitude of the fast inertia gravity oscillations that are generated spontaneously, through what is shown to be a Stokes phenomenon. This estimate is given by 2??-2 exp[-?/(2)], where 1 is proportional to the Rossby number and the prefactor ? is determined from recurrence relations. The nonlinear dependence of ? on the O(1) rotational Froude number indicates that the feedback of the inertia gravity waves on the balanced motion directly affects their amplitude.Numerical experiments confirm the analytic results. Optimally truncated slaving relations are used to separate the exponentially small inertia gravity oscillations from the (much larger) slow contribution to the dependent variables. This makes it possible to examine the switching on of the oscillations in detail; it is shown to be described by an error function of t/1/2 as predicted theoretically. The results derived for the homoclinic solution of Lorenz and Krishnamurthy are extended to more general, periodic, solutions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25099516','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25099516"><span id="translatedtitle"><span class="hlt">Models</span> and mechanisms of Hofmeister effects in electrolyte solutions, and colloid and protein systems <span class="hlt">revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Salis, Andrea; Ninham, Barry W</p> <p>2014-11-01</p> <p>Specific effects of electrolytes have posed a challenge since the 1880's. The pioneering work was that of Franz Hofmeister who studied specific salt induced protein precipitation. These effects are the rule rather the exception and are ubiquitous in chemistry and biology. Conventional electrostatic theories (Debye-Hückel, DLVO, etc.) cannot explain such effects. Over the past decades it has been recognised that additional quantum mechanical dispersion forces with associated hydration effects acting on ions are missing from theory. In parallel Collins has proposed a phenomenological set of rules (the law of matching water affinities, LMWA) which explain and bring to order the order of ion-ion and ion-surface site interactions at a qualitative level. The two approaches appear to conflict. Although the need for inclusion of quantum dispersion forces in one form or another is not questioned, the <span class="hlt">modelling</span> has often been misleading and inappropriate. It does not properly describe the chemical nature (kosmotropic/chaotropic or hard/soft) of the interacting species. The success of the LMWA rules lies in the fact that they do. Here we point to the way that the two apparently opposing approaches might be reconciled. Notwithstanding, there are more challenges, which deal with the effect of dissolved gas and its connection to 'hydrophobic' interactions, the problem of water at different temperatures and 'water structure' in the presence of solutes. They take us to another dimension that requires the rebuilding of theoretical foundations. PMID:25099516</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22130987','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22130987"><span id="translatedtitle">THERMAL NON-EQUILIBRIUM <span class="hlt">REVISITED</span>: A HEATING <span class="hlt">MODEL</span> FOR CORONAL LOOPS</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Lionello, Roberto; Linker, Jon A.; Mikic, Zoran; Winebarger, Amy R.; Mok, Yung E-mail: linkerj@predsci.com E-mail: amy.r.winebarger@nasa.gov</p> <p>2013-08-20</p> <p>The location and frequency of events that heat the million-degree corona are still a matter of debate. One potential heating scenario is that the energy release is effectively steady and highly localized at the footpoints of coronal structures. Such an energy deposition drives thermal non-equilibrium solutions in the hydrodynamic equations in longer loops. This heating scenario was considered and discarded by Klimchuk et al. on the basis of their one-dimensional simulations as incapable of reproducing observational characteristics of loops. In this paper, we use three-dimensional simulations to generate synthetic emission images, from which we select and analyze six loops. The main differences between our <span class="hlt">model</span> and that of Klimchuk et al. concern (1) dimensionality, (2) resolution, (3) geometrical properties of the loops, (4) heating function, and (5) radiative function. We find evidence, in this small set of simulated loops, that the evolution of the light curves, the variation of temperature along the loops, the density profile, and the absence of small-scale structures are compatible with the characteristics of observed loops. We conclude that quasi-steady footpoint heating that drives thermal non-equilibrium solutions cannot yet be ruled out as a viable heating scenario for EUV loops.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26443104','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26443104"><span id="translatedtitle"><span class="hlt">Revisiting</span> the chlorophyll biosynthesis pathway using genome scale metabolic <span class="hlt">model</span> of Oryza sativa japonica.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Chatterjee, Ankita; Kundu, Sudip</p> <p>2015-01-01</p> <p>Chlorophyll is one of the most important pigments present in green plants and rice is one of the major food crops consumed worldwide. We curated the existing genome scale metabolic <span class="hlt">model</span> (GSM) of rice leaf by incorporating new compartment, reactions and transporters. We used this modified GSM to elucidate how the chlorophyll is synthesized in a leaf through a series of bio-chemical reactions spanned over different organelles using inorganic macronutrients and light energy. We predicted the essential reactions and the associated genes of chlorophyll synthesis and validated against the existing experimental evidences. Further, ammonia is known to be the preferred source of nitrogen in rice paddy fields. The ammonia entering into the plant is assimilated in the root and leaf. The focus of the present work is centered on rice leaf metabolism. We studied the relative importance of ammonia transporters through the chloroplast and the cytosol and their interlink with other intracellular transporters. Ammonia assimilation in the leaves takes place by the enzyme glutamine synthetase (GS) which is present in the cytosol (GS1) and chloroplast (GS2). Our results provided possible explanation why GS2 mutants show normal growth under minimum photorespiration and appear chlorotic when exposed to air. PMID:26443104</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/769210','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/769210"><span id="translatedtitle">EQUATION OF STATE AND HUGONIOT LOCUS FOR POROUS MATERIALS: P-ALPHA <span class="hlt">MODEL</span> <span class="hlt">REVISITED</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>R. MENIKOFF; ET AL</p> <p>1999-08-01</p> <p>Foams, porous solids and granular materials have a characteristic Hugoniot locus that for weak shocks is concave in the (particle velocity, shock velocity)-plane. An equation of state (EOS) that has this property can be constructed implicitly from a Helmholtz free energy of the form {Psi}{sub s}(V,T,{phi}) = {Psi}{sub s}(V,T)+B({phi}) where the equilibrium volume fraction {phi}{sub eq} is determined by minimizing {Psi}, i.e., the condition {partial_derivative}{sub {psi}} {Psi} = 0. For many cases, a Hayes EOS for the pure solid {Psi}{sub s}(V,T) is adequate. This provides a thermodynamically consistent framework for the P-{alpha} <span class="hlt">model</span>. For this form of EOS the volume fraction has a similar effect to an endothermic reaction in that the partial Hugoniot loci with fixed {psi} are shifted to the left in the (V,P)-plane with increasing f. The equilibrium volume fraction can then be chosen to match the concavity of the principal Hugoniot locus. An example is presented for the polymer estane. A small porosity of only 1.4 percent is required to match the experimental concavity in the Hugoniot data. This type of EOS can also be used to obtain the so-called ''universal'' Hugoniot for liquids.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013CliPD...9.1509L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013CliPD...9.1509L"><span id="translatedtitle">The faint young Sun problem <span class="hlt">revisited</span> with a 3-D climate-carbon <span class="hlt">model</span> - Part 1</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Le Hir, G.; Teitler, Y.; Fluteau, F.; Donnadieu, Y.; Philippot, P.</p> <p>2013-03-01</p> <p>Considering the weak luminosity of the early Sun, it is generally inferred that high concentrations of greenhouse gases (CO2, CH4) are required to prevent the early Earth's surface temperature to drop below the freezing point of liquid water. Conversely, a new controversial assumption based on banded iron formation mineralogy hypothesizes that the Archean atmosphere was potentially characterized by low concentrations of CO2. To solve the faint young Sun problem, it was suggested that a reduced albedo associated to less reflective clouds was able to prevent the Earth to jump into a snowball state. In this very active debate, we have investigated the early Earth climate using a general circulation <span class="hlt">model</span> to test this scenario. Our simulations include the ice albedo feedback and specific Archean climatic factors such as a different cloudiness, a faster Earth's rotation rate, and a reduced continental surface. We demonstrate that when larger cloud droplets are accounted for, clouds warm high latitudes and inhibit sea-ice formation. This process limits the ice-albedo feedback efficiency and may prevent a global glaciation. Due to this particular mechanism, low pCO2 allow maintaining a mild climate during the early Archean. This conclusion will be challenged in the second part of this paper, where the carbon cycle is considered.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1999APS..SHK..G201M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1999APS..SHK..G201M"><span id="translatedtitle">Equation of State and Hugoniot locus for porous materials: P--? <span class="hlt">model</span> <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Menikoff, Ralph; Kober, Edward</p> <p>1999-06-01</p> <p>Foams, porous solids and granular materials have a characteristic Hugoniot locus that for weak shocks is concave in the (particle velocity, shock velocity)-plane. An equation of state (EOS) that has this property can be constructed implicitly from a Helmholtz free energy of the form F(V,T,?) = F_s(V,T) + B(?) where the equilibrium volume fraction ?_eq is determined by minimizing F, phi.e., the condition partial_? F = 0. For many cases, a Hayes EOS for the pure solid F_s(V,T) is adequate. This provides a thermodynamically consistent framework for the P--? <span class="hlt">model</span>. For this form of EOS, we show that the volume fraction has a similar effect to an endothermic reaction in that the partial Hugoniot loci with fixed ? are shifted to the left in the (V,P)-plane with increasing ?. The equilibrium volume fraction can then be chosen to match the concavity of the principal Hugoniot locus. An example is presented for the polymer estane. A small porosity of only 1.4 per cent is required to match the experimental concavity in the Hugoniot data. This type of EOS can also be used to obtain the so-called ``universal'' Hugoniot for liquids.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_12 --> <div id="page_13" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="241"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2000AIPC..505..129M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2000AIPC..505..129M"><span id="translatedtitle">Equation of state and Hugoniot locus for porous materials: P-? <span class="hlt">model</span> <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Menikoff, Ralph; Kober, Edward</p> <p>2000-04-01</p> <p>Foams, porous solids and granular materials have a characteristic Hugoniot locus that for weak shocks is concave in the (particle velocity, shock velocity)-plane. An equation of state (EOS) that has this property can be constructed implicitly from a Helmholtz free energy of the form ?(V,T,?)=?s(V,T)+B(?) where the equilibrium volume fraction ?eq is determined by minimizing ?, i.e., the condition ???=0. For many cases, a Hayes EOS for the pure solid ?s(V,T) is adequate. This provides a thermodynamically consistent framework for the P-? <span class="hlt">model</span>. For this form of EOS the volume fraction has a similar effect to an endothermic reaction in that the partial Hugoniot loci with fixed ? are shifted to the left in the (V,P)-plane with increasing ?. The equilibrium volume fraction can then be chosen to match the concavity of the principal Hugoniot locus. An example is presented for the polymer estane. A small porosity of only 1.4 percent is required to match the experimental concavity in the Hugoniot data. This type of EOS can also be used to obtain the so-called "universal" Hugoniot for liquids.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/197560','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/197560"><span id="translatedtitle">An integrative <span class="hlt">model</span> for the treatment of psychosomatic disorders. The place of sleep and dreams <span class="hlt">revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Warnes, H</p> <p></p> <p>The functions and dysfunctions of slow wave sleep and of REM sleep and its associated dreams have a tremendous significance in understanding the psychosomatic <span class="hlt">model</span> of illness and in establishing preventive strategies. Ten patients suffering from a variety of psychosomatic illnessess spent 3-4 nights sleeping at the Dream Laboratory. A psychiatric evaluation was carried out and those suffering from schizophrenia, severe depression, acute stage of physical illness and organic deficits were not accepted for the study. It was postulated that increased psychosomatic 'penetrance' as measured by poverty of fantasy life, feelings of helplessness, absence of dream reports, vacant and contrived emotional expression and poor psychological mindedness would be correlated with psychological test results (IPAT anxiety Scale and Zung Depression Rating Scale), manifest dream content analysis and particular REM and stage 4 deficit. The higher psychosomatic 'penetrance' in our study was not found in all patients with a psychosomatic diagnosis but rather in those patients suffering from ulcerative colitis. The degree of 'penetrance' was related to specific physiological, psychological and interpersonal parameters. Based on these findings a spectrum of clinical and physiological criteria of selection for particular therapeutic intervention was presented. PMID:197560</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4595741','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4595741"><span id="translatedtitle"><span class="hlt">Revisiting</span> the chlorophyll biosynthesis pathway using genome scale metabolic <span class="hlt">model</span> of Oryza sativa japonica</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Chatterjee, Ankita; Kundu, Sudip</p> <p>2015-01-01</p> <p>Chlorophyll is one of the most important pigments present in green plants and rice is one of the major food crops consumed worldwide. We curated the existing genome scale metabolic <span class="hlt">model</span> (GSM) of rice leaf by incorporating new compartment, reactions and transporters. We used this modified GSM to elucidate how the chlorophyll is synthesized in a leaf through a series of bio-chemical reactions spanned over different organelles using inorganic macronutrients and light energy. We predicted the essential reactions and the associated genes of chlorophyll synthesis and validated against the existing experimental evidences. Further, ammonia is known to be the preferred source of nitrogen in rice paddy fields. The ammonia entering into the plant is assimilated in the root and leaf. The focus of the present work is centered on rice leaf metabolism. We studied the relative importance of ammonia transporters through the chloroplast and the cytosol and their interlink with other intracellular transporters. Ammonia assimilation in the leaves takes place by the enzyme glutamine synthetase (GS) which is present in the cytosol (GS1) and chloroplast (GS2). Our results provided possible explanation why GS2 mutants show normal growth under minimum photorespiration and appear chlorotic when exposed to air. PMID:26443104</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26621920','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26621920"><span id="translatedtitle">Postnatal pituitary and follicular activation: a <span class="hlt">revisited</span> hypothesis in a sheep <span class="hlt">model</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Torres-Rovira, Laura; Succu, Sara; Pasciu, Valeria; Manca, Maria Elena; Gonzalez-Bulnes, Antonio; Leoni, Giovanni Giuseppe; Pennino, Maria Grazia; Spezzigu, Antonio; Gallus, Marilia; Dattena, Maria; Monniaux, Danielle; Naitana, Salvatore; Berlinguer, Fiammetta</p> <p>2016-03-01</p> <p>The importance of postnatal pituitary activation as regards female reproductive development is not yet understood. By taking advantage of the experimental <span class="hlt">model</span> developed in a previous study, i.e. ewe lambs expressing markedly different ovarian phenotypes at 50 days of age, we designed this study to determine whether differences found in ovarian status during the early prepubertal period are due to different patterns of postnatal pituitary activation, and to assess whether these differences have long lasting effects on subsequent reproductive performance. Results showed that ewe lambs with high antral follicle count (AFC) at 50 days of age had significantly lower plasma FSH concentrations and higher anti-Mullerian hormone (AMH) concentrations during the first 9 weeks of age compared with low AFC ewe lambs (P<0.0001). With a longitudinal experiment we showed that a high AFC in the early prepubertal period is associated with consistently higher AMH concentrations and numbers of antral follicles up to the postpubertal period, and with higher pregnancy rates in the first breeding season. In addition, the effect of age in decreasing AMH concentrations was more marked in the low AFC group. Results of the present study demonstrate that ewe lambs undergo different patterns of postnatal pituitary activation. A high AFC at 50 days of age indicates an advanced phase of ovarian maturation, which was accompanied by constantly higher AMH concentrations up to the postpubertal period, a greater ovarian response to FSH stimulation and by higher pregnancy rates at first mating, as compared with the low AFC group. PMID:26621920</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013hell.confS..17G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013hell.confS..17G"><span id="translatedtitle">The global polytropic <span class="hlt">model</span> for the solar and jovian systems <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Geroyannis, V.; Valvi, F.; Dallas, T.</p> <p>2013-09-01</p> <p>The "global polytropic <span class="hlt">model</span>" (Geroyannis) 1993 [P1]; Geroyannis and Valvi 1994 [P2]) is based on the assumption of hydrostatic equilibrium for the solar/jovian system, described by the Lane-Emden differential equation. A polytropic sphere of polytropic index n and radius R1 represents the central component S1 (Sun/Jupiter) of a polytropic configuration with further components the polytropic spherical shells S2, S3, ..., defined by the pairs of radii (R1,R2), (R2,R3), ..., respectively. R1, R2, R3, ..., are the roots of the real part Re(theta(R)) of the complex Lane-Emden function theta(R). Each polytropic shell is assumed to be an appropriate place for a planet/satellite to be "born" and "live". This scenario has been studied numerically for the case of the solar system (P1) and the jovian system (P2). In the present paper, the Lane-Emden differential equation is solved numerically in the complex plane by using the Fortran code dcrkf54.f95 (Geroyannis and Valvi 2012; modified Runge-Kutta- Fehlberg code of fourth and fifth order for solving initial value problems in the complex plane). We include in our numerical study some trans-Neptunian objects. We emphasize on computing distances and comparing with previous results. REFERENCES: V.S. Geroyannis 1993, Earth, Moon, and Planets, 61, 131-139. V.S. Geroyannis and F.N. Valvi 1994, Earth, Moon, and Planets, 64, 217-225. V.S. Geroyannis and F.N. Valvi 2012, International Journal of Modern Physics C, 23, No 5, 1250038:1-15.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2585069','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2585069"><span id="translatedtitle">Fibronectin Unfolding <span class="hlt">Revisited</span>: <span class="hlt">Modeling</span> Cell Traction-Mediated Unfolding of the Tenth Type-III Repeat</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Gee, Elaine P. S.; Ingber, Donald E.; Stultz, Collin M.</p> <p>2008-01-01</p> <p>Fibronectin polymerization is essential for the development and repair of the extracellular matrix. Consequently, deciphering the mechanism of fibronectin fibril formation is of immense interest. Fibronectin fibrillogenesis is driven by cell-traction forces that mechanically unfold particular modules within fibronectin. Previously, mechanical unfolding of fibronectin has been <span class="hlt">modeled</span> by applying tensile forces at the N- and C-termini of fibronectin domains; however, physiological loading is likely focused on the solvent-exposed RGD loop in the 10th type-III repeat of fibronectin (10FNIII), which mediates binding to cell-surface integrin receptors. In this work we used steered molecular dynamics to study the mechanical unfolding of 10FNIII under tensile force applied at this RGD site. We demonstrate that mechanically unfolding 10FNIII by pulling at the RGD site requires less work than unfolding by pulling at the N- and C- termini. Moreover, pulling at the N- and C-termini leads to 10FNIII unfolding along several pathways while pulling on the RGD site leads to a single exclusive unfolding pathway that includes a partially unfolded intermediate with exposed hydrophobic N-terminal β-strands – residues that may facilitate fibronectin self-association. Additional mechanical unfolding triggers an essential arginine residue, which is required for high affinity binding to integrins, to move to a position far from the integrin binding site. This cell traction-induced conformational change may promote cell detachment after important partially unfolded kinetic intermediates are formed. These data suggest a novel mechanism that explains how cell-mediated forces promote fibronectin fibrillogenesis and how cell surface integrins detach from newly forming fibrils. This process enables cells to bind and unfold additional fibronectin modules – a method that propagates matrix assembly. PMID:19020673</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4112007','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4112007"><span id="translatedtitle">Meta-Analytic Connectivity <span class="hlt">Modelling</span> <span class="hlt">Revisited</span>: Controlling for Activation Base Rates</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Langner, Robert; Rottschy, Claudia; Laird, Angela R.; Fox, Peter T.; Eickhoff, Simon B.</p> <p>2014-01-01</p> <p>Co-activation of distinct brain regions is a measure of functional interaction, or connectivity, between those regions. The co-activation pattern of a given region can be investigated using seed-based activation likelihood estimation meta-analysis of functional neuroimaging data stored in databases such as BrainMap. This method reveals inter-regional functional connectivity by determining brain regions that are consistently co-activated with a given region of interest (the seed) across a broad range of experiments. In current implementations of this meta-analytic connectivity <span class="hlt">modelling</span> (MACM), significant spatial convergence (i.e. consistent co-activation) is distinguished from noise by comparing it against an unbiased null-distribution of random spatial associations between experiments according to which all grey-matter voxels have the same chance of convergence. As the a priori probability of finding activation in different voxels markedly differs across the brain, computing such a quasi-rectangular null-distribution renders the detection of significant convergence more likely in those voxels that are frequently activated. Here, we propose and test a modified MACM approach that takes this activation frequency bias into account. In this new specific co-activation likelihood estimation (SCALE) algorithm, a null-distribution is generated that reflects the base rate of reporting activation in any given voxel and thus equalizes the a priori chance of finding across-study convergence in each voxel of the brain. Using four exemplary seed regions (right visual area V4, left anterior insula, right intraparietal sulcus, and subgenual cingulum), our tests corroborated the enhanced specificity of the modified algorithm, indicating that SCALE may be especially useful for delineating distinct core networks of co-activation. PMID:24945668</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010MNRAS.402.1141G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010MNRAS.402.1141G"><span id="translatedtitle"><span class="hlt">Revisiting</span> 2D numerical <span class="hlt">models</span> for the 19th century outbursts of ? Carinae</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gonzlez, R. F.; Villa, A. M.; Gmez, G. C.; de Gouveia Dal Pino, E. M.; Raga, A. C.; Cant, J.; Velzquez, P. F.; de La Fuente, E.</p> <p>2010-02-01</p> <p>We present here new results of two-dimensional hydrodynamical simulations of the eruptive events of the 1840s (the great) and the 1890s (the minor) eruptions suffered by the massive star ? Carinae (Car). The two bipolar nebulae commonly known as the Homunculus and the little Homunculus (LH) were formed from the interaction of these eruptive events with the underlying stellar wind. We assume here an interacting, non-spherical multiple-phase wind scenario to explain the shape and the kinematics of both Homunculi, but adopt a more realistic parametrization of the phases of the wind. During the 1890s eruptive event, the outflow speed decreased for a short period of time. This fact suggests that the LH is formed when the eruption ends, from the impact of the post-outburst ? Car wind (that follows the 1890s event) with the eruptive flow (rather than by the collision of the eruptive flow with the pre-outburst wind, as claimed in previous <span class="hlt">models</span>; Gonzlez et al.). Our simulations reproduce quite well the shape and the observed expansion speed of the large Homunculus. The LH (which is embedded within the large Homunculus) becomes Rayleigh-Taylor unstable and develop filamentary structures that resemble the spatial features observed in the polar caps. In addition, we find that the interior cavity between the two Homunculi is partially filled by material that is expelled during the decades following the great eruption. This result may be connected with the observed double-shell structure in the polar lobes of the ? Car nebula. Finally, as in previous work, we find the formation of tenuous, equatorial, high-speed features that seem to be related to the observed equatorial skirt of ? Car.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21163674','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21163674"><span id="translatedtitle">Two-dimensional thermofield bosonization II: Massive fermions</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Amaral, R.L.P.G.</p> <p>2008-11-15</p> <p>We consider the perturbative computation of the N-point function of chiral densities of massive free fermions at finite temperature within the thermofield dynamics approach. The infinite series in the mass parameter for the N-point functions are computed in the fermionic formulation and compared with the corresponding perturbative series in the interaction parameter in the bosonized thermofield formulation. Thereby we establish in thermofield dynamics the formal equivalence of the massive free fermion theory with the <span class="hlt">sine-Gordon</span> thermofield <span class="hlt">model</span> for a particular value of the <span class="hlt">sine-Gordon</span> parameter. We extend the thermofield bosonization to include the massive Thirring <span class="hlt">model</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006MolPh.104.2901S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006MolPh.104.2901S"><span id="translatedtitle">Zwanzig <span class="hlt">model</span> of multi-component mixtures of biaxial particles: y3 theory <span class="hlt">re-visited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sokolova, E. P.; Tumanyan, N. P.; Vlasov, A. Yu.; Masters, A. J.</p> <p></p> <p>The paper considers the thermodynamic and phase ordering properties of a multi-component Zwanzig mixture of hard rectangular biaxial parallelepipeds. An equation of state (EOS) is derived based on an estimate of the number of arrangements of the particles on a three- dimensional cubic lattice. The methodology is a generalization of the Flory-DiMarzio counting scheme, but, unlike previous work, this treatment is thermodynamically consistent. The results are independent of the order in which particles are placed on the lattice. By taking the limit of zero lattice spacing, a translationally continuous variant of the <span class="hlt">model</span> (the off-lattice variant) is obtained. The EOS is identical to that obtained previously by a wide variety of different approaches. In the off-lattice limit, it corresponds to a third-level y-expansion and, in the case of a binary mixture of square platelets, it also corresponds to the EOS obtained from fundamental measure theory. On the lattice it is identical to the EOS obtained by retaining only complete stars in the virial expansion. The off-lattice theory is used to study binary mixtures of rods (R1 - R2) and binary mixtures of platelets (P1 - P2). The particles were uniaxial, of length (thickness) L and width D. The aspect ratios ?i = Li/Di of the components were kept constant (?1R = 15, ?1P = 1/15 and ?2R = 150, ?2P = 1/150), so the second virial coefficient of R1 was identical to P1 and similarly for R2 and P2. The volume ratio of particles 1 and 2, v1/v2, was then varied, with the constraints that viR = viP and ILM0001. Results on nematic-isotropic (N - I) phase coexistence at an infinite dilution of component 2, are qualitatively similar for rods and platelets. At small values of the ratio v1/v2, the addition of component 2 (i.e. a thin rod (e.g. a polymer) or a thin plate) results in the stabilization of the nematic phase. For larger values of v1/v2, however, this effect is reversed and the addition of component 2 destabilizes the nematic. For similar molecular volumes of the two components strong fractionation is observed: shorter rods and thicker platelets congregate in the isotropic phase. In general, the stabilization of the ordered phase and the fractionation between the phases are both weaker in the platelet mixtures. The calculated spinodal curves for isotropic-isotropic demixing are noticeably different between the R1 - R2 and the P1 - P2 systems. The platelet mixtures turn out to be stable with respect to de-mixing up to extremely high densities. The values of the consolute points for the R1 - R2 blends are remarkably similar to those obtained using the Parsons-Lee approximation for bi-disperse mixtures of freely rotating cylinders with similar aspect ratios [S. Varga. A. Galindo, G. Jackson, Mol. Phys., 101, 817 (2003)]. In a number of R1 - R2 mixtures, phase diagrams exhibiting both N - I equilibrium and I - I de-mixing were calculated. The latter is pre-empted by nematic ordering in all the cases studied. Calculations show the possible appearance of azeotropes in the N - I coexistence domain.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015NatPh..11..369S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015NatPh..11..369S"><span id="translatedtitle">Programming <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schulthess, Thomas C.</p> <p>2015-05-01</p> <p>Writing efficient scientific software that makes best use of the increasing complexity of computer architectures requires bringing together <span class="hlt">modelling</span>, applied mathematics and computer engineering. Physics may help unite these approaches.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2000PhDT.......236K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2000PhDT.......236K"><span id="translatedtitle">Lie algebraic structures in integrable <span class="hlt">models</span>, affine Toda field theory</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Korff, Christian</p> <p>2000-08-01</p> <p>The most prominent class of integrable quantum field theories in 1+1 dimensions is affine Toda theory. Distinguished by a rich underlying Lie algebraic structure these <span class="hlt">models</span> have in recent years attracted much attention not only as test laboratories for non-perturbative methods in quantum field theory but also in the context of off-critical <span class="hlt">models</span>. After a short introduction the mathematical preliminaries such as root systems, Coxeter geometry, dual algebras, q-deformed Coxeter elements and q-deformed Cartan matrices are introduced. Using this mathematical framework the bootstrap analysis of the affine Toda S-matrices with real coupling is performed and several universal Lie algebraic formulae proved. The Lie algebraic methods are then extended to define a new class of colour valued S-matrices and also here universal expressions are derived. The second part of the thesis presents a detailed analysis of the high-energy regime of the integrable <span class="hlt">models</span> discussed in the first part. By means of the thermodynamic Bethe ansatz the central charges of the ultraviolet conformal field theories are calculated and in case of affine Toda theories also the first order term in the scaling function is analytically obtained. For the colour valued S-matrices the connection to WZNW coset <span class="hlt">models</span> is discussed. A particular subclass of them, the so-called Homogeneous <span class="hlt">Sine-Gordon</span> <span class="hlt">models</span>, is investigated in some detail and it is found that the presence of unstable particles in these theories gives rise to a staircase pattern in the corresponding scaling function. This thesis summarizes the results of previously published articles listed in the introduction.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=leadership+AND+sociology&pg=5&id=EJ583758','ERIC'); return false;" href="http://eric.ed.gov/?q=leadership+AND+sociology&pg=5&id=EJ583758"><span id="translatedtitle">Leadership Giftedness: <span class="hlt">Models</span> <span class="hlt">Revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Roach, Adelma A.; Wyman, Leisy T.; Brookes, Heather; Chavez, Christina; Heath, Shirley Brice; Valdes, Guadalupe</p> <p>1999-01-01</p> <p>A decade-long study in underserved and at-risk communities evaluated young people identified as leaders within out-of-school youth organizations. Findings revealed that emerging youth leadership differs from established measures and leadership theories drawn from adults with a greater emphasis on how leadership happens, rather than who leaders…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21432426','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21432426"><span id="translatedtitle">Exact solutions for a Maxwell-Kalb-Ramond action with dilaton: Localization of massless and massive modes in a <span class="hlt">sine-Gordon</span> brane-world</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Christiansen, H. R.; Cunha, M. S.; Tahim, M. O.</p> <p>2010-10-15</p> <p>We analytically find the exact propagation modes of the electromagnetic and the Kalb-Ramond fields together in a five-dimensional curved space-time. The existence and localization of gauge particles into our four-dimensional world (4D) is studied in detail on a brane-world scenario in which two gauge fields interact with a dilaton and a gravitational background. The coupling to the dilaton is different in each case causing the splitting between gauge spectra. The gauge-field zero-modes and an infinite tower of Kaluza-Klein massive states are analytically obtained. Relevant conditions on the dilaton coupling constant are found in order to identify with precision every finite tensor and vector eigenstate in the theory. An exact quantization condition on the whole mass spectrum, depending on the dilaton coupling constant and the bulk Planck mass, is inherited from the extra-dimension. This allows finding an exact rule to prevent tachyons in the theory and, by the same token, predicting a possible tensor zero-mode in 4D world. We also show that KK massive-modes contributions onto 4D physics are strongly suppressed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=bernoulli&pg=2&id=EJ913086','ERIC'); return false;" href="http://eric.ed.gov/?q=bernoulli&pg=2&id=EJ913086"><span id="translatedtitle">Siphons, <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Richert, Alex; Binder, P. -M.</p> <p>2011-01-01</p> <p>The siphon is a very useful example of early technology, the operation of which has long been well understood. A recent article makes the claim that established beliefs regarding this device are incorrect and proposes a "chain <span class="hlt">model</span>" in which intermolecular forces within the fluid play a large role while atmospheric pressure does not. We have</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=pressure+AND+experiment&pg=4&id=EJ913086','ERIC'); return false;" href="http://eric.ed.gov/?q=pressure+AND+experiment&pg=4&id=EJ913086"><span id="translatedtitle">Siphons, <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Richert, Alex; Binder, P. -M.</p> <p>2011-01-01</p> <p>The siphon is a very useful example of early technology, the operation of which has long been well understood. A recent article makes the claim that established beliefs regarding this device are incorrect and proposes a "chain <span class="hlt">model</span>" in which intermolecular forces within the fluid play a large role while atmospheric pressure does not. We have…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015WRR....51.3145Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015WRR....51.3145Y"><span id="translatedtitle">Comparison of three dual-source remote sensing evapotranspiration <span class="hlt">models</span> during the MUSOEXE-12 campaign: <span class="hlt">Revisit</span> of <span class="hlt">model</span> physics</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yang, Yuting; Long, Di; Guan, Huade; Liang, Wei; Simmons, Craig; Batelaan, Okke</p> <p>2015-05-01</p> <p>Various remote sensing-based terrestrial evapotranspiration (ET) <span class="hlt">models</span> have been developed during the past four decades. These <span class="hlt">models</span> vary in conceptual and mathematical representations of the physics, consequently leading to different performances. Examination of uncertainties associated with limitations in <span class="hlt">model</span> physics will be useful for <span class="hlt">model</span> selection and improvement. Here, three dual-source remote sensing ET <span class="hlt">models</span> (i.e., the Hybrid dual-source scheme and Trapezoid framework-based ET <span class="hlt">Model</span> (HTEM), the Two-Source Energy Balance (TSEB) <span class="hlt">model</span>, and the MOD16 ET algorithm) using ASTER images were compared during the MUSOEXE-12 campaign in the Heihe River Basin in Northwest China, aiming to better understand the differences in <span class="hlt">model</span> physics that potentially lead to differences in <span class="hlt">model</span> performance. <span class="hlt">Model</span> results were first compared against observations from a dense network of eddy covariance towers and isotope-based evaporation (E) and transpiration (T) partitioning. Results show that HTEM outperformed the other two <span class="hlt">models</span> in simulating ET and its partitioning, whereas MOD16 performed worst (i.e., ET root-mean-square errors are 42.3 W/m2 (HTEM), 49.8 W/m2 (TSEB), and 95.3 W/m2 (MOD16)). On to <span class="hlt">model</span> limitations, HTEM tends to underestimate ET under high advection due mostly to the underestimation of temperatures for the wet edge in its trapezoidal space. For TSEB, large uncertainties occur in determining the initial Priestley-Taylor coefficient and the iteration procedure for ET partitioning, leading to overestimation/underestimation of T/E in most cases, particularly over sparse vegetation. Primary use of meteorological data for MOD16 does not effectively capture the soil moisture restriction on ET, and therefore results in unreasonable spatial ET patterns.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011PhTea..49...78R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011PhTea..49...78R"><span id="translatedtitle">Siphons, <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Richert, Alex; Binder, P.-M.</p> <p>2011-02-01</p> <p>The siphon is a very useful example of early technology, the operation of which has long been well understood. A recent article makes the claim that established beliefs regarding this device are incorrect and proposes a "chain <span class="hlt">model</span>" in which intermolecular forces within the fluid play a large role while atmospheric pressure does not. We have carefully tested, and disproved, this claim using four simple experiments employing inexpensive, easily available apparatus. We complement the experiments with a discussion of conceptual issues related to the device and by invoking earlier studies and observations.2-8 Our findings fully support an explanation based on Bernoulli's equation in which both gravity and pressure play important roles, but intermolecular forces do not.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015SPIE.9475E..0HH','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015SPIE.9475E..0HH"><span id="translatedtitle">Multinomial pattern matching <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Horvath, Matthew S.; Rigling, Brian D.</p> <p>2015-05-01</p> <p>Multinomial pattern matching (MPM) is an automatic target recognition algorithm developed for specifically radar data at Sandia National Laboratories. The algorithm is in a family of algorithms that first quantizes pixel value into Nq bins based on pixel amplitude before training and classification. This quantization step reduces the sensitivity of algorithm performance to absolute intensity variation in the data, typical of radar data where signatures exhibit high variation for even small changes in aspect angle. Our previous work has focused on performance analysis of peaky template matching, a special case of MPM where binary quantization is used (Nq = 2). Unfortunately references on these algorithms are generally difficult to locate and here we <span class="hlt">revisit</span> the MPM algorithm and illustrate the underlying statistical <span class="hlt">model</span> and decision rules for two algorithm interpretations: the 1-of-K vector form and the scalar. MPM can also be used as a detector and specific attention is given to algorithm tuning where "peak pixels" are chosen based on their underlying empirical probabilities according to a reward minimization strategy aimed at reducing false alarms in the detection scenario and false positives in a classification capacity. The algorithms are demonstrated using Monte Carlo simulations on the AFRL civilian vehicle dataset for variety of choices of Nq.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/943975','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/943975"><span id="translatedtitle">Searle's"Dualism <span class="hlt">Revisited</span>"</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>P., Henry</p> <p>2008-11-20</p> <p>A recent article in which John Searle claims to refute dualism is examined from a scientific perspective. John Searle begins his recent article 'Dualism <span class="hlt">Revisited</span>' by stating his belief that the philosophical problem of consciousness has a scientific solution. He then claims to refute dualism. It is therefore appropriate to examine his arguments against dualism from a scientific perspective. Scientific physical theories contain two kinds of descriptions: (1) Descriptions of our empirical findings, expressed in an every-day language that allows us communicate to each other our sensory experiences pertaining to what we have done and what we have learned; and (2) Descriptions of a theoretical <span class="hlt">model</span>, expressed in a mathematical language that allows us to communicate to each other certain ideas that exist in our mathematical imaginations, and that are believed to represent, within our streams of consciousness, certain aspects of reality that we deem to exist independently of their being perceived by any human observer. These two parts of our scientific description correspond to the two aspects of our general contemporary dualistic understanding of the total reality in which we are imbedded, namely the empirical-mental aspect and the theoretical-physical aspect. The duality question is whether this general dualistic understanding of ourselves should be regarded as false in some important philosophical or scientific sense.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_13 --> <div id="page_14" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="261"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012BoLMe.144..199S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012BoLMe.144..199S"><span id="translatedtitle">The Apsley and Castro Limited-Length-Scale {{k-\\varepsilon}} <span class="hlt">Model</span> <span class="hlt">Revisited</span> for Improved Performance in the Atmospheric Surface Layer</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sumner, Jonathon; Masson, Christian</p> <p>2012-08-01</p> <p>The limited-length-scale {k-\\varepsilon} <span class="hlt">model</span> proposed by Apsley and Castro for the atmospheric boundary layer (Boundary-Layer Meteorol 83(1):75-98, 1997) is <span class="hlt">revisited</span> with special attention given to its predictions in the constant-stress surface layer. The original <span class="hlt">model</span> proposes a modification to the length-scale-governing {\\varepsilon} equation that ensures consistency with surface-layer scaling in the limit of small ? m/ ? max (where ? m is the mixing length and ? max its maximum) and yet imposes a limit on ? m as ? m/ ? max approaches one. However, within the equilibrium surface layer and for moderate values of z/ ? max, the predicted profiles of velocity, mixing length, and dissipation rate using the Apsley and Castro <span class="hlt">model</span> do not coincide with analytical solutions. In view of this, a general {\\varepsilon} transport equation is derived herein in terms of an arbitrary desired mixing-length expression that ensures exact agreement with corresponding analytical solutions for both neutral and stable stability. From this result, a new expression for {C_{\\varepsilon3}} can be inferred that shows this coefficient tends to a constant only for limiting values of z/ L; and, furthermore, that the values of {C_{\\varepsilon3}} for z/ L ? 0 and z/ L ?? differ by a factor of exactly two.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3924568','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3924568"><span id="translatedtitle"><span class="hlt">Revisiting</span> Mednick’s <span class="hlt">Model</span> on Creativity-Related Differences in Associative Hierarchies. Evidence for a Common Path to Uncommon Thought</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Benedek, Mathias; Neubauer, Aljoscha C</p> <p>2013-01-01</p> <p>Fifty years ago, Mednick [Psychological Review, 69 (1962) 220] proposed an elaborate <span class="hlt">model</span> that aimed to explain how creative ideas are generated and why creative people are more likely to have creative ideas. The <span class="hlt">model</span> assumes that creative people have flatter associative hierarchies and as a consequence can more fluently retrieve remote associative elements, which can be combined to form creative ideas. This study aimed at <span class="hlt">revisiting</span> Mednick’s <span class="hlt">model</span> and providing an extensive test of its hypotheses. A continuous free association task was employed and association performance was compared between groups high and low in creativity, as defined by divergent thinking ability and self-report measures. We found that associative hierarchies do not differ between low and high creative people, but creative people showed higher associative fluency and more uncommon responses. This suggests that creativity may not be related to a special organization of associative memory, but rather to a more effective way of accessing its contents. The findings add to the evidence associating creativity with highly adaptive executive functioning. PMID:24532853</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/6414996','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/6414996"><span id="translatedtitle">Chaos and order in non-integrable <span class="hlt">model</span> field theories</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Campbell, D.K.; Peyrard, M.</p> <p>1989-01-01</p> <p>We illustrate the presence of chaos and order in non-integrable, classical field theories, which we view as many-degree-of-freedom Hamiltonian nonlinear dynamical systems. For definiteness, we focus on the {chi}{sup 4} theory and compare and contrast it with the celebrated integrable <span class="hlt">sine-Gordon</span> equation. We introduce and investigate two specific problems: the interactions of solitary kink''-like waves in non-integrable theories; and the existence of stable breather'' solutions -- spatially-localized, time-periodic nonlinear waves -- in the {chi}{sup 4} theory. For the former problem we review the rather well developed understanding, based on a combination of computational simulations and heuristic analytic <span class="hlt">models</span>, of the presence of a sequence of resonances in the kink-antikink interactions as a function of the relative velocity of the interaction. For the latter problem we discuss first the case of the continuum {chi}{sup 4} theory. We discuss the multiple-scale asymptotic perturbation theory arguments which first suggested the existence of {chi}{sup 4} breathers, then the subsequent discovery of terms beyond-all-orders'' in the perturbation expansion which destroy the putative breather, and finally, the recent rigorous proofs of the non-existence of breathers in the continuum theory. We then present some very recent numerical results on the existence of breathers in discrete {chi}{sup 4} theories which show an intricate interweaving of stable and unstable breather solutions on finite discrete lattices. We develop a heuristic theoretical explanation of the regions of stability and instability.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=judith+AND+butler&pg=3&id=EJ987054','ERIC'); return false;" href="http://eric.ed.gov/?q=judith+AND+butler&pg=3&id=EJ987054"><span id="translatedtitle">The Linguistic Repertoire <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Busch, Brigitta</p> <p>2012-01-01</p> <p>This article argues for the relevance of poststructuralist approaches to the notion of a linguistic repertoire and introduces the notion of language portraits as a basis for empirical study of the way in which speakers conceive and represent their heteroglossic repertoires. The first part of the article <span class="hlt">revisits</span> Gumperz's notion of a linguistic</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=rhetoric&id=EJ986586','ERIC'); return false;" href="http://eric.ed.gov/?q=rhetoric&id=EJ986586"><span id="translatedtitle"><span class="hlt">Revisiting</span> the Rhetorical Curriculum</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Rutten, Kris; Soetaert, Ronald</p> <p>2012-01-01</p> <p>The aim of the special strand on "<span class="hlt">Revisiting</span> the rhetorical curriculum" is to explore the educational potential of a new rhetorical perspective, specifically in relation to different traditions within educational and rhetorical studies. This implies that we do not only look at education "in" rhetoric, but that we position education also "as" a</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=198247&keyword=Benefit+AND+food&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=57523334&CFTOKEN=84490965','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=198247&keyword=Benefit+AND+food&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=57523334&CFTOKEN=84490965"><span id="translatedtitle"><span class="hlt">Revisiting</span> Bioaccumulation Criteria</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>The objective of workgroup 5 was to <span class="hlt">revisit</span> the B(ioaccumulation) criteria that are currently being used to identify POPs under the Stockholm Convention and PBTs under CEPA, TSCA, REACh and other programs. Despite the lack of a recognized definition for a B substance, we defined ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=water+AND+well&pg=3&id=EJ985093','ERIC'); return false;" href="http://eric.ed.gov/?q=water+AND+well&pg=3&id=EJ985093"><span id="translatedtitle">A Hydrostatic Paradox <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Ganci, Salvatore</p> <p>2012-01-01</p> <p>This paper <span class="hlt">revisits</span> a well-known hydrostatic paradox, observed when turning upside down a glass partially filled with water and covered with a sheet of light material. The phenomenon is studied in its most general form by including the mass of the cover. A historical survey of this experiment shows that a common misunderstanding of the phenomenon…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=bats&pg=3&id=EJ858639','ERIC'); return false;" href="http://eric.ed.gov/?q=bats&pg=3&id=EJ858639"><span id="translatedtitle">Colloquial Hebrew Imperatives <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Bolozky, Shmuel</p> <p>2009-01-01</p> <p>In <span class="hlt">revisiting</span> Bolozky's [Bolozky, Shmuel, 1979. "On the new imperative in colloquial Hebrew." "Hebrew Annual Review" 3, 17-24] and Bat-El's [Bat-El, Outi, 2002. "True truncation in colloquial Hebrew imperatives." "Language" 78(4), 651-683] analyses of colloquial Hebrew imperatives, the article argues for restricting Imperative Truncation to the…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=BATS&pg=3&id=EJ858639','ERIC'); return false;" href="http://eric.ed.gov/?q=BATS&pg=3&id=EJ858639"><span id="translatedtitle">Colloquial Hebrew Imperatives <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Bolozky, Shmuel</p> <p>2009-01-01</p> <p>In <span class="hlt">revisiting</span> Bolozky's [Bolozky, Shmuel, 1979. "On the new imperative in colloquial Hebrew." "Hebrew Annual Review" 3, 17-24] and Bat-El's [Bat-El, Outi, 2002. "True truncation in colloquial Hebrew imperatives." "Language" 78(4), 651-683] analyses of colloquial Hebrew imperatives, the article argues for restricting Imperative Truncation to the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=light+AND+water&id=EJ985093','ERIC'); return false;" href="http://eric.ed.gov/?q=light+AND+water&id=EJ985093"><span id="translatedtitle">A Hydrostatic Paradox <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Ganci, Salvatore</p> <p>2012-01-01</p> <p>This paper <span class="hlt">revisits</span> a well-known hydrostatic paradox, observed when turning upside down a glass partially filled with water and covered with a sheet of light material. The phenomenon is studied in its most general form by including the mass of the cover. A historical survey of this experiment shows that a common misunderstanding of the phenomenon</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2013-title42-vol5/pdf/CFR-2013-title42-vol5-sec488-30.pdf','CFR2013'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2013-title42-vol5/pdf/CFR-2013-title42-vol5-sec488-30.pdf"><span id="translatedtitle">42 CFR 488.30 - <span class="hlt">Revisit</span> user fee for <span class="hlt">revisit</span> surveys.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2013&page.go=Go">Code of Federal Regulations, 2013 CFR</a></p> <p></p> <p>2013-10-01</p> <p>... 42 Public Health 5 2013-10-01 2013-10-01 false <span class="hlt">Revisit</span> user fee for <span class="hlt">revisit</span> surveys. 488.30... Provisions 488.30 <span class="hlt">Revisit</span> user fee for <span class="hlt">revisit</span> surveys. (a) Definitions. As used in this section, the... be subject to user fees unless otherwise exempted. <span class="hlt">Revisit</span> survey means a survey performed...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2014-title42-vol5/pdf/CFR-2014-title42-vol5-sec488-30.pdf','CFR2014'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2014-title42-vol5/pdf/CFR-2014-title42-vol5-sec488-30.pdf"><span id="translatedtitle">42 CFR 488.30 - <span class="hlt">Revisit</span> user fee for <span class="hlt">revisit</span> surveys.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2014&page.go=Go">Code of Federal Regulations, 2014 CFR</a></p> <p></p> <p>2014-10-01</p> <p>... 42 Public Health 5 2014-10-01 2014-10-01 false <span class="hlt">Revisit</span> user fee for <span class="hlt">revisit</span> surveys. 488.30... Provisions 488.30 <span class="hlt">Revisit</span> user fee for <span class="hlt">revisit</span> surveys. (a) Definitions. As used in this section, the... subject to user fees unless otherwise exempted. <span class="hlt">Revisit</span> survey means a survey performed with respect to...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2012-title42-vol5/pdf/CFR-2012-title42-vol5-sec488-30.pdf','CFR2012'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2012-title42-vol5/pdf/CFR-2012-title42-vol5-sec488-30.pdf"><span id="translatedtitle">42 CFR 488.30 - <span class="hlt">Revisit</span> user fee for <span class="hlt">revisit</span> surveys.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2012&page.go=Go">Code of Federal Regulations, 2012 CFR</a></p> <p></p> <p>2012-10-01</p> <p>... 42 Public Health 5 2012-10-01 2012-10-01 false <span class="hlt">Revisit</span> user fee for <span class="hlt">revisit</span> surveys. 488.30... Provisions 488.30 <span class="hlt">Revisit</span> user fee for <span class="hlt">revisit</span> surveys. (a) Definitions. As used in this section, the... be subject to user fees unless otherwise exempted. <span class="hlt">Revisit</span> survey means a survey performed...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2010-title42-vol5/pdf/CFR-2010-title42-vol5-sec488-30.pdf','CFR'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2010-title42-vol5/pdf/CFR-2010-title42-vol5-sec488-30.pdf"><span id="translatedtitle">42 CFR 488.30 - <span class="hlt">Revisit</span> user fee for <span class="hlt">revisit</span> surveys.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2010&page.go=Go">Code of Federal Regulations, 2010 CFR</a></p> <p></p> <p>2010-10-01</p> <p>... 42 Public Health 5 2010-10-01 2010-10-01 false <span class="hlt">Revisit</span> user fee for <span class="hlt">revisit</span> surveys. 488.30... Provisions 488.30 <span class="hlt">Revisit</span> user fee for <span class="hlt">revisit</span> surveys. (a) Definitions. As used in this section, the... be subject to user fees unless otherwise exempted. <span class="hlt">Revisit</span> survey means a survey performed...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2011-title42-vol5/pdf/CFR-2011-title42-vol5-sec488-30.pdf','CFR2011'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2011-title42-vol5/pdf/CFR-2011-title42-vol5-sec488-30.pdf"><span id="translatedtitle">42 CFR 488.30 - <span class="hlt">Revisit</span> user fee for <span class="hlt">revisit</span> surveys.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2011&page.go=Go">Code of Federal Regulations, 2011 CFR</a></p> <p></p> <p>2011-10-01</p> <p>... 42 Public Health 5 2011-10-01 2011-10-01 false <span class="hlt">Revisit</span> user fee for <span class="hlt">revisit</span> surveys. 488.30... Provisions 488.30 <span class="hlt">Revisit</span> user fee for <span class="hlt">revisit</span> surveys. (a) Definitions. As used in this section, the... be subject to user fees unless otherwise exempted. <span class="hlt">Revisit</span> survey means a survey performed...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002IJMPB..16.4685B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002IJMPB..16.4685B"><span id="translatedtitle">The Fermion-Boson Mapping Applied to Lagrangian <span class="hlt">Models</span> for Charge-Density-Waves in One-Dimensional Systems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Belvedere, L. V.; Amaral, R. L. P. G.; de Queiroz, A. F.</p> <p></p> <p>We use the two-dimensional Fermion-Boson mapping to perform a field theory analysis of the effective Lagrangian <span class="hlt">model</span> for incommensurate charge-density waves (ICDW) in one-dimensional systems. We consider an approach in which both the phase of the complex phonon field and the electron field are dynamical degrees of freedom contributing to the quantum dynamics and symmetry-related features of the ICDW phenomenon. We obtain the bosonized and fermionized versions of the effective electron-phonon Lagrangian. The phase of the phonon field and the phase of the bosonized chiral density of the electron field condense as a soliton order parameter, carrying neither the charge nor the chirality of the electron-phonon system, leading to a periodic <span class="hlt">sine-Gordon</span> potential. The phonon field is fermionized in terms of a chiral fermionic condensate and the effective <span class="hlt">model</span> is mapped into the chiral Gross-Neveu (GN) <span class="hlt">model</span> with two Fermi field species. The linked electron-phonon symmetry of the ICDW system is mapped into the chiral symmetry of the GN <span class="hlt">model</span>. Within the functional integral formulation, we obtain for the vacuum expectation value of the phonon field < ? > = 0 and < ? ?ast > ? 0, due to the charge selection rule associated with the chiral electron-phonon symmetry. We show that the two-point correlation function of the phonon field satisfies the cluster decomposition property, as required by the chiral symmetry of the underlying GN <span class="hlt">model</span>. The quantum description of the ICDW corresponds to charge transport through the lattice, due to the propagation of a ``Goldstone mode'' carrying the effective charge of the electron-phonon system, is accomplished by an electron-lattice energy redistribution. This accounts for a dynamical Peierls's energy gap generation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JHEP...03..005B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JHEP...03..005B"><span id="translatedtitle">Quasi-integrability in the modified defocusing non-linear Schrödinger <span class="hlt">model</span> and dark solitons</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Blas, H.; Zambrano, M.</p> <p>2016-03-01</p> <p>The concept of quasi-integrability has been examined in the context of deformations of the defocusing non-linear Schrödinger <span class="hlt">model</span> (NLS). Our results show that the quasi-integrability concept, recently discussed in the context of deformations of the <span class="hlt">sine-Gordon</span>, Bullough-Dodd and focusing NLS <span class="hlt">models</span>, holds for the modified defocusing NLS <span class="hlt">model</span> with dark soliton solutions and it exhibits the new feature of an infinite sequence of alternating conserved and asymptotically conserved charges. For the special case of two dark soliton solutions, where the field components are eigenstates of a space-reflection symmetry, the first four and the sequence of even order charges are exactly conserved in the scattering process of the solitons. Such results are obtained through analytical and numerical methods, and employ adaptations of algebraic techniques used in integrable field theories. We perform extensive numerical simulations and consider the scattering of dark solitons for the cubic-quintic NLS <span class="hlt">model</span> with potential V=η {I}^2-in /6{I}^3 and the saturable type potential satisfying [InlineEquation not available: see fulltext.], with a deformation parameter ɛ ∈ [InlineMediaObject not available: see fulltext.] and I = | ψ|2. The issue of the renormalization of the charges and anomalies, and their (quasi)conservation laws are properly addressed. The saturable NLS supports elastic scattering of two soliton solutions for a wide range of values of { η, ɛ, q}. Our results may find potential applications in several areas of non-linear science, such as the Bose-Einstein condensation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/18300683','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/18300683"><span id="translatedtitle">Orthopaedic service lines-<span class="hlt">revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Patterson, Cheryl</p> <p>2008-01-01</p> <p>This article <span class="hlt">revisits</span> the application of orthopaedic service lines from early introduction and growth of this organizational approach in the 1980s, through the 1990s, and into the current decade. The author has experienced and worked in various service-line structures through these three decades, as well as the preservice-line era of 1970s orthopaedics. Past lessons learned during earlier phases and then current trends and analysis by industry experts are summarized briefly, with indication given of the future for service lines. Variation versus consistency of certain elements in service-line definitions and in operational <span class="hlt">models</span> is discussed. Main components of service-line structures and typical processes are described briefly, along with a more detailed section on the service-line director/manager role. Current knowledge contained here will help guide the reader to more "out-of-the-box" thinking toward comprehensive orthopaedic centers of excellence. PMID:18300683</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015IJGMM..1260027F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015IJGMM..1260027F"><span id="translatedtitle">Time functions <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fathi, Albert</p> <p>2015-07-01</p> <p>In this paper we <span class="hlt">revisit</span> our joint work with Antonio Siconolfi on time functions. We will give a brief introduction to the subject. We will then show how to construct a Lipschitz time function in a simplified setting. We will end with a new result showing that the Aubry set is not an artifact of our proof of existence of time functions for stably causal manifolds.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=32193','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=32193"><span id="translatedtitle">Clinical ethics <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Singer, Peter A; Pellegrino, Edmund D; Siegler, Mark</p> <p>2001-01-01</p> <p>A decade ago, we reviewed the field of clinical ethics; assessed its progress in research, education, and ethics committees and consultation; and made predictions about the future of the field. In this article, we <span class="hlt">revisit</span> clinical ethics to examine our earlier observations, highlight key developments, and discuss remaining challenges for clinical ethics, including the need to develop a global perspective on clinical ethics problems. PMID:11346456</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_14 --> <div id="page_15" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="281"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=jesus&pg=2&id=EJ983492','ERIC'); return false;" href="http://eric.ed.gov/?q=jesus&pg=2&id=EJ983492"><span id="translatedtitle"><span class="hlt">Revisiting</span> Dialogues and Monologues</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Kvernbekk, Tone</p> <p>2012-01-01</p> <p>In educational discourse dialogue tends to be viewed as being (morally) superior to monologue. When we look at them as basic forms of communication, we find that dialogue is a two-way, one-to-one form and monologue is a one-way, one-to-many form. In this paper I <span class="hlt">revisit</span> the alleged (moral) superiority of dialogue. First, I problematize certain…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Jesus&pg=2&id=EJ983492','ERIC'); return false;" href="http://eric.ed.gov/?q=Jesus&pg=2&id=EJ983492"><span id="translatedtitle"><span class="hlt">Revisiting</span> Dialogues and Monologues</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Kvernbekk, Tone</p> <p>2012-01-01</p> <p>In educational discourse dialogue tends to be viewed as being (morally) superior to monologue. When we look at them as basic forms of communication, we find that dialogue is a two-way, one-to-one form and monologue is a one-way, one-to-many form. In this paper I <span class="hlt">revisit</span> the alleged (moral) superiority of dialogue. First, I problematize certain</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/16224717','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/16224717"><span id="translatedtitle">The mid-domain effect <span class="hlt">revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zapata, Fernando A; Gaston, Kevin J; Chown, Steven L</p> <p>2005-11-01</p> <p>We <span class="hlt">revisit</span> the proposition that boundary constraints on species' ranges cause species richness gradients (the mid-domain effect [MDE] hypothesis). In the absence of environmental gradients, species should not retain their observed range sizes as assumed by MDE <span class="hlt">models</span>. Debate remains regarding the definition of domain limits, valid predictions for testing the <span class="hlt">models</span>, and their statistical assessment. Empirical support for the MDE is varied but often weak, suggesting that geometric constraints on species' ranges do not provide a general explanation for richness gradients. Criticism of MDE <span class="hlt">model</span> assumptions does not, however, imply opposition to the use of null <span class="hlt">models</span> in ecology. PMID:16224717</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.8274M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.8274M"><span id="translatedtitle">Dynamic Topography <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Moresi, Louis</p> <p>2015-04-01</p> <p>Dynamic Topography <span class="hlt">Revisited</span> Dynamic topography is usually considered to be one of the trinity of contributing causes to the Earth's non-hydrostatic topography along with the long-term elastic strength of the lithosphere and isostatic responses to density anomalies within the lithosphere. Dynamic topography, thought of this way, is what is left over when other sources of support have been eliminated. An alternate and explicit definition of dynamic topography is that deflection of the surface which is attributable to creeping viscous flow. The problem with the first definition of dynamic topography is 1) that the lithosphere is almost certainly a visco-elastic / brittle layer with no absolute boundary between flowing and static regions, and 2) the lithosphere is, a thermal / compositional boundary layer in which some buoyancy is attributable to immutable, intrinsic density variations and some is due to thermal anomalies which are coupled to the flow. In each case, it is difficult to draw a sharp line between each contribution to the overall topography. The second definition of dynamic topography does seem cleaner / more precise but it suffers from the problem that it is not measurable in practice. On the other hand, this approach has resulted in a rich literature concerning the analysis of large scale geoid and topography and the relation to buoyancy and mechanical properties of the Earth [e.g. refs 1,2,3] In convection <span class="hlt">models</span> with viscous, elastic, brittle rheology and compositional buoyancy, however, it is possible to examine how the surface topography (and geoid) are supported and how different ways of interpreting the "observable" fields introduce different biases. This is what we will do. References (a.k.a. homework) [1] Hager, B. H., R. W. Clayton, M. A. Richards, R. P. Comer, and A. M. Dziewonski (1985), Lower mantle heterogeneity, dynamic topography and the geoid, Nature, 313(6003), 541-545, doi:10.1038/313541a0. [2] Parsons, B., and S. Daly (1983), The relationship between surface topography, gravity anomalies, and temperature structure of convection, Journal of Geophysical Research: Solid Earth (1978-2012), 88(B2), 1129-1144, doi:10.1029/JB088iB02p01129. [3] Robinson, E. M., B. Parsons, and S. F. Daly (1987), The effect of a shallow low viscosity zone on the apparent compensation of mid-plate swells, Earth and Planetary Science Letters, 82(3-4), 335-348, doi:10.1016/0012-821X(87)90207-X.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Self-respect&pg=7&id=EJ789056','ERIC'); return false;" href="http://eric.ed.gov/?q=Self-respect&pg=7&id=EJ789056"><span id="translatedtitle">The Internal/External Frame of Reference <span class="hlt">Model</span> <span class="hlt">Revisited</span>: Incorporating General Cognitive Ability and General Academic Self-Concept</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Brunner, Martin; Ludtke, Oliver; Trautwein, Ulrich</p> <p>2008-01-01</p> <p>The internal/external frame of reference <span class="hlt">model</span> (I/E <span class="hlt">model</span>; Marsh, 1986) is a highly influential <span class="hlt">model</span> of self-concept formation, which predicts that domain-specific abilities have positive effects on academic self-concepts in the corresponding domain and negative effects across domains. Investigations of the I/E <span class="hlt">model</span> do not typically incorporate</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.P53B1855C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.P53B1855C"><span id="translatedtitle">Radiolytic Cryovolcanism <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cooper, J. F.; Cooper, P. D.; Sittler, E. C.; Wesenberg, R. P.</p> <p>2013-12-01</p> <p>Active geysers of water vapor and ice grains from the south pole of Enceladus are not yet definitively explained in terms of energy sources and processes. Other instances of hot (Io) and cold (Mars, Triton) volcanism beyond Earth are known if not fully understood. We <span class="hlt">revisit</span>, in comparison to other <span class="hlt">models</span>, the 'Old Faithful' theory of radiolytic gas-driven cryovolcanism first proposed by Cooper et al. [Plan. Sp. Sci. 2009]. In the energetic electron irradiation environment of Enceladus within Saturn's magnetosphere, a 10-percent duty cycle could be maintained for current geyser activity driven by gases from oxidation of ammonia to N2 and methane to CO2 in the thermal margins of a south polar sea. Much shorter duty cycles down to 0.01 percent would be required to account for thermal power output up to 16 GW, Steady accumulation of oxidant energy over four billion years could have powered all Enceladus emissions over the past four hundred thousand to four hundred million years. There could be separate energy sources driving mass flow and thermal emission over vastly different time scales. Since episodic tidal dissipation on 10 Myr time scales at 0.1 - 1 Gyr intervals [O'Neill and Nimmo, Nature 2010], and thus duty cycles 1 - 10 percent, could heat the polar sea to the current level, the radiolytic energy source could easily power and modulate the geyser mass flow on million-year time scales. Maximum thermal emission temperature 223 K [Abramov and Spencer, Icarus 2009] hints at thermal buffering in the basal and vent wall layers by a 1:1 H2O:H2O2 radiolytic eutectic, assuming deep ice crust saturation with H2O2 from long cumulative surface irradiation and downward ice convection. Due to density stratification the peroxide eutectic and salt water layers could separate, so that the denser peroxide layer (1.2 g/cc) descends to the polar sea while the lighter salt water (1.05 g/cc) rises along separate channels. Methane reservoirs could be found dissolved into the polar sea, or else trapped in hydrates [Kieffer et al., Science 2006] along flow paths and at the walls of the polar sea at surface depths below 20 km [Fortes, Icarus 2007]. Driver gas production for cryovolcanism could occur wherever these two layers come into contact under requisite temperature and pressure conditions, e.g. from 220 K and 10 bar at the 10-km basal layer of the overlying ice crust to 647 K and 220 bars at the liquid water limit, above the core-mantle boundary at 460 bars [Fortes, Icarus 2007]. We expect H2O2 oxidation to ignite at high temperatures but metallic minerals could catalyze reactions at lower temperatures nearer the basal layer. Pressure effects on oxidation rates are uncertain. Definitive <span class="hlt">modeling</span> of Enceladus cryovolcanism likely involves synthesis of key processes from multiple <span class="hlt">models</span>: Cold Faithful [Porco et al., Science 2006], Frigid Faithful [Keiffer et al., Science 2006], Frothy Faithful [Fortes, Icarus 2007], Old Faithful, and 'Perrier Ocean' recirculation [Matson et al., Icarus 2012].</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006PhFl...18g3101L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006PhFl...18g3101L"><span id="translatedtitle">Multicomponent diffusion <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lam, S. H.</p> <p>2006-07-01</p> <p>The derivation of the multicomponent diffusion law is <span class="hlt">revisited</span>. Following Furry [Am. J. Phys. 16, 63 (1948)], Williams [Am. J. Phys. 26, 467 (1958); Combustion Theory, 2nd ed. (Benjamin/Cummings , Menlo Park, CA,1985)] heuristically rederived the classical kinetic theory results using macroscopic equations, and pointed out that the dynamics of the mixture fluid had been assumed inviscid. This paper generalizes the derivation, shows that the inviscid assumption can easily be relaxed to add a new term to the classical diffusion law, and the thermal diffusion term can also be easily recovered. The nonuniqueness of the multicomponent diffusion coefficient matrix is emphasized and discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20050182780','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20050182780"><span id="translatedtitle">Temporal Dynamic Controllability <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Morris, Paul H.; Muscettola, Nicola</p> <p>2005-01-01</p> <p>An important issue for temporal planners is the ability to handle temporal uncertainty. We <span class="hlt">revisit</span> the question of how to determine whether a given set of temporal requirements are feasible in the light of uncertain durations of some processes. In particular, we consider how best to determine whether a network is Dynamically Controllable, i.e., whether a dynamic strategy exists for executing the network that is guaranteed to satisfy the requirements. Previous work has shown the existence of a pseudo-polynomial algorithm for testing Dynamic Controllability. Here, we greatly simplify the previous framework, and present a true polynomial algorithm with a cutoff based only on the number of nodes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26812257','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26812257"><span id="translatedtitle">QMRA for Drinking Water: 1. <span class="hlt">Revisiting</span> the Mathematical Structure of Single-Hit Dose-Response <span class="hlt">Models</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Nilsen, Vegard; Wyller, John</p> <p>2016-01-01</p> <p>Dose-response <span class="hlt">models</span> are essential to quantitative microbial risk assessment (QMRA), providing a link between levels of human exposure to pathogens and the probability of negative health outcomes. In drinking water studies, the class of semi-mechanistic <span class="hlt">models</span> known as single-hit <span class="hlt">models</span>, such as the exponential and the exact beta-Poisson, has seen widespread use. In this work, an attempt is made to carefully develop the general mathematical single-hit framework while explicitly accounting for variation in (1) host susceptibility and (2) pathogen infectivity. This allows a precise interpretation of the so-called single-hit probability and precise identification of a set of statistical independence assumptions that are sufficient to arrive at single-hit <span class="hlt">models</span>. Further analysis of the <span class="hlt">model</span> framework is facilitated by formulating the single-hit <span class="hlt">models</span> compactly using probability generating and moment generating functions. Among the more practically relevant conclusions drawn are: (1) for any dose distribution, variation in host susceptibility always reduces the single-hit risk compared to a constant host susceptibility (assuming equal mean susceptibilities), (2) the <span class="hlt">model</span>-consistent representation of complete host immunity is formally demonstrated to be a simple scaling of the response, (3) the <span class="hlt">model</span>-consistent expression for the total risk from repeated exposures deviates (gives lower risk) from the conventional expression used in applications, and (4) a <span class="hlt">model</span>-consistent expression for the mean per-exposure dose that produces the correct total risk from repeated exposures is developed. PMID:26812257</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4807457','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4807457"><span id="translatedtitle">Hodgkin–Huxley <span class="hlt">revisited</span>: reparametrization and identifiability analysis of the classic action potential <span class="hlt">model</span> with approximate Bayesian methods</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Daly, Aidan C.; Holmes, Chris</p> <p>2015-01-01</p> <p>As cardiac cell <span class="hlt">models</span> become increasingly complex, a correspondingly complex ‘genealogy’ of inherited parameter values has also emerged. The result has been the loss of a direct link between <span class="hlt">model</span> parameters and experimental data, limiting both reproducibility and the ability to re-fit to new data. We examine the ability of approximate Bayesian computation (ABC) to infer parameter distributions in the seminal action potential <span class="hlt">model</span> of Hodgkin and Huxley, for which an immediate and documented connection to experimental results exists. The ability of ABC to produce tight posteriors around the reported values for the gating rates of sodium and potassium ion channels validates the precision of this early work, while the highly variable posteriors around certain voltage dependency parameters suggests that voltage clamp experiments alone are insufficient to constrain the full <span class="hlt">model</span>. Despite this, Hodgkin and Huxley's estimates are shown to be competitive with those produced by ABC, and the variable behaviour of posterior parametrized <span class="hlt">models</span> under complex voltage protocols suggests that with additional data the <span class="hlt">model</span> could be fully constrained. This work will provide the starting point for a full identifiability analysis of commonly used cardiac <span class="hlt">models</span>, as well as a template for informative, data-driven parametrization of newly proposed <span class="hlt">models</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=preprofessional+AND+practices&pg=4&id=ED410202','ERIC'); return false;" href="http://eric.ed.gov/?q=preprofessional+AND+practices&pg=4&id=ED410202"><span id="translatedtitle">Dewey <span class="hlt">Revisited</span>: A Pragmatic-Experiential <span class="hlt">Model</span> for Teacher Education. A Thematic Topic for "The Educational Forum."</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Wilson, Jan; Baird, Debra</p> <p></p> <p>This paper shares the development and evolution of a pragmatic-experiential <span class="hlt">model</span> of teacher education at the University of West Alabama. The <span class="hlt">model</span> is grounded in the theories and philosophies promoted by Dewey and James. The philosophy of pragmatism encourages testing the authenticity or truth of ideas through experience. Experientialism, an</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..12.7433F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..12.7433F"><span id="translatedtitle">"The right answer for the wrong reason" <span class="hlt">revisited</span>: validation of a spatially-explicit soil erosion <span class="hlt">model</span> (RillGrow)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Favis-Mortlock, David</p> <p>2010-05-01</p> <p>One finding from the GCTE evaluation of soil erosion <span class="hlt">models</span> (Jetten et al., 1999) is that the <span class="hlt">models</span> tested were, in general, weak regarding the spatial aspects of erosion. A perfectly adequate simulation of runoff and soil loss at the catchment outlet could be produced even if the <span class="hlt">model</span> did a poor job of identifying the location of erosion hotspots within that catchment. Spatially, the <span class="hlt">models</span> could give "the right answer for the wrong reason". As well as casting doubt on the validity of process representations within such a <span class="hlt">model</span>, this kind of result is clearly unacceptable when using it to plan or evaluate soil conservation measures within the catchment. With this as a background, the RillGrow series of soil erosion <span class="hlt">models</span> were developed. These represent an eroding hillslope area as a self-organizing system (e.g. Favis-Mortlock, 1998; Favis-Mortlock et al., 2000). Microtopography is considered to determine the spatial pattern of overland flow and hence of surface lowering; such lowering modifies the path of subsequent flow. This simple iterative relationship generates rill networks emergently, i.e. as a collective whole-system response to many local interactions. The approach removes a requirement of many erosion <span class="hlt">models</span>: the need to pre-specify' rill characteristics even for an unrilled surface. However, computational constraints currently confine RillGrow to simulation of small, plot-sized, areas. Even on such small areas however, <span class="hlt">model</span> validation is not straightforward. In a series of validation studies, DEMs of the microtopography of real soil surfaces (from both laboratory flumes and hillslope plots) were used as inputs to the RillGrow <span class="hlt">model</span>. <span class="hlt">Model</span>-simulated rill networks were then compared with those which developed on the real soil surfaces. Other <span class="hlt">model</span> outputs (e.g. hydrographs and sedigraphs at the outlet; water depths and velocities at points on the surface) were similarly compared. While conceptually simple, problems with this approach include: * The difficulty of objectively comparing two rilled soil surfaces. Real and <span class="hlt">modelled</span> surfaces might appear very similar, but if planwise rill locations differ by even a few mm, then correlation-based measures indicate a poor result. The converse can also be true. * Flow velocity within rills can vary widely over short distances. However velocity values obtained using e.g. dye tracers have had this small-scale variation smoothed away. How should such values be compared with point-based simulated flow velocity values? Such ambiguities once again open the possibility of obtaining "the right answer for the wrong reason". Thus this paper highlights these and other issues which can arise when validating a spatially-explicit soil erosion <span class="hlt">model</span> such as RillGrow.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AGUFM.H13D0996Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AGUFM.H13D0996Y"><span id="translatedtitle">A functional <span class="hlt">model</span> of watershed-scale annual water balance partitioning: Lvovich, Ponce and Shetty <span class="hlt">revisited</span> (Invited)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yaeger, M. A.; Harman, C. J.; Troch, P. A.; Sivapalan, M.</p> <p>2009-12-01</p> <p>Ponce and Shetty (1995), building on the results of the previous global empirical work of Lvovich (1979), developed a functional <span class="hlt">model</span> of watershed water balance at the annual time scale. This <span class="hlt">model</span> conceptualized the rainfall partitioning in terms of a two stage competition between alternative fluxes or flow pathways. At the surface level the competition between infiltration (wetting) and quickflow governs the partitioning of incoming precipitation. At the subsurface level the competition between vaporization (evapotranspiration) and baseflow governs the partitioning of the wetted amount (wetting). The <span class="hlt">model</span> equations consist of identical functional forms for both of these stages and are characterized by 2 parameters in each case. In the first case, quickflow occurs only when precipitation exceeds a minimum threshold, but beyond that it can increase unbounded with precipitation. On the other hand, wetting increases monotonically at first but gradually asymptotes to an upper threshold. The second stage partitioning is assumed to occur in similar fashion, resulting in a lower threshold of wetting that is required to generate baseflow, and an upper bound to the vaporization amount. The four parameters of the <span class="hlt">models</span> are simply the two minimum threshold values and the two upper bounds. In this study, systematic baseflow separation was done using 50 years of daily rainfall-runoff data from 431 MOPEX catchments located around the United States to estimate the four annual water balance components using annual precipitation: quickflow, wetting, baseflow and vaporization. The Ponce and Shetty functional <span class="hlt">model</span> was then fitted to these components, calibrating to determine the four <span class="hlt">model</span> parameters. Using these parameters, the <span class="hlt">model</span> was used to analytically derive both the mean and variance of the Horton Index, which is defined as the ratio of annual vaporization to annual wetting. The results showed excellent agreement with the observed mean Horton Index, but systematically under-predicted its variance, which so far has defied explanation. The threshold values showed interesting spatial patterns across the US that may be related to climate and topography. The usefulness of this <span class="hlt">model</span> is that it can be easily applied to any catchment with precipitation and flow data. The way forward may be to explore the mechanisms through which the functional forms of the Ponce and Shetty <span class="hlt">model</span> may have emerged as a manifestation of small scale process interactions. This will help provide physical meanings to the four <span class="hlt">model</span> parameters. This exploration is left for further work.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/15923917','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/15923917"><span id="translatedtitle">A practical method of predicting client <span class="hlt">revisit</span> intention in a hospital setting.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lee, Kyun Jick</p> <p>2005-01-01</p> <p>Data mining (DM) <span class="hlt">models</span> are an alternative to traditional statistical methods for examining whether higher customer satisfaction leads to higher <span class="hlt">revisit</span> intention. This study used a total of 906 outpatients' satisfaction data collected from a nationwide survey interviews conducted by professional interviewers on a face-to-face basis in South Korea, 1998. Analyses showed that the relationship between overall satisfaction with hospital services and outpatients' <span class="hlt">revisit</span> intention, along with word-of-mouth recommendation as intermediate variables, developed into a nonlinear relationship. The five strongest predictors of <span class="hlt">revisit</span> intention were overall satisfaction, intention to recommend to others, awareness of hospital promotion, satisfaction with physician's kindness, and satisfaction with treatment level. PMID:15923917</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/EJ1079231.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/EJ1079231.pdf"><span id="translatedtitle"><span class="hlt">Revisiting</span> Constructivist Teaching Methods in Ontario Colleges Preparing for Accreditation</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Schultz, Rachel A.</p> <p>2015-01-01</p> <p>At the time of writing, the first community colleges in Ontario were preparing for transition to an accreditation <span class="hlt">model</span> from an audit system. This paper <span class="hlt">revisits</span> constructivist literature, arguing that a more pragmatic definition of constructivism effectively blends positivist and interactionist philosophies to achieve both student centred…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=management+AND+organisation&pg=3&id=EJ923093','ERIC'); return false;" href="http://eric.ed.gov/?q=management+AND+organisation&pg=3&id=EJ923093"><span id="translatedtitle">Can an Opportunity to Learn at Work Reduce Stress?: A <span class="hlt">Revisitation</span> of the Job Demand-Control <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Panari, Chiara; Guglielmi, Dina; Simbula, Silvia; Depolo, Marco</p> <p>2010-01-01</p> <p>Purpose: This paper aims to extend the stress-buffering hypothesis of the demand-control <span class="hlt">model</span>. In addition to the control variable, it seeks to analyse the role of an opportunity for learning and development (L&D) in the workplace as a moderator variable between increased demands and need for recovery. Design/methodology/approach: A questionnaire</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/ED097404.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/ED097404.pdf"><span id="translatedtitle">A Simultaneous Equations <span class="hlt">Model</span> of the Educational Process: The Coleman Data <span class="hlt">Revisited</span> with an Emphasis on Achievement.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Boardman, Anthony E.; And Others</p> <p></p> <p>This paper has two main purposes. First, it examines verbal, nonverbal, reading, mathematical, and general informational achievement. Second, it estimates the achievement equations of a simultaneous equations <span class="hlt">model</span> of the educational process. The report, "Equality of Educational Opportunity," (EEOR) acted as a watershed for research into</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=facebook+OR+eating+AND+disorder&pg=4&id=EJ934459','ERIC'); return false;" href="http://eric.ed.gov/?q=facebook+OR+eating+AND+disorder&pg=4&id=EJ934459"><span id="translatedtitle"><span class="hlt">Revisiting</span> the Affect Regulation <span class="hlt">Model</span> of Binge Eating: A Meta-Analysis of Studies Using Ecological Momentary Assessment</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Haedt-Matt, Alissa A.; Keel, Pamela K.</p> <p>2011-01-01</p> <p>The affect regulation <span class="hlt">model</span> of binge eating, which posits that patients binge eat to reduce negative affect (NA), has received support from cross-sectional and laboratory-based studies. Ecological momentary assessment (EMA) involves momentary ratings and repeated assessments over time and is ideally suited to identify temporal antecedents and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Bulimia&pg=2&id=EJ934459','ERIC'); return false;" href="http://eric.ed.gov/?q=Bulimia&pg=2&id=EJ934459"><span id="translatedtitle"><span class="hlt">Revisiting</span> the Affect Regulation <span class="hlt">Model</span> of Binge Eating: A Meta-Analysis of Studies Using Ecological Momentary Assessment</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Haedt-Matt, Alissa A.; Keel, Pamela K.</p> <p>2011-01-01</p> <p>The affect regulation <span class="hlt">model</span> of binge eating, which posits that patients binge eat to reduce negative affect (NA), has received support from cross-sectional and laboratory-based studies. Ecological momentary assessment (EMA) involves momentary ratings and repeated assessments over time and is ideally suited to identify temporal antecedents and…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21392312','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21392312"><span id="translatedtitle">A <span class="hlt">REVISIT</span> OF THE TWO-POLE CAUSTIC <span class="hlt">MODEL</span> FOR GeV LIGHT CURVES OF GAMMA-RAY PULSARS</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Fang, J.; Zhang, L.</p> <p>2010-02-01</p> <p>The GeV light curve of a pulsar is an important probe to detect acceleration regions in its magnetosphere. Motivated by the recent reports on the observations of pulsars by the Fermi Large Area Telescope, we restudy the two-pole caustic <span class="hlt">model</span> and revise it to investigate the properties of the light curves in the GeV band. In the revised <span class="hlt">model</span>, although acceleration gaps can extend from the star surface to the light cylinder along near the last open field lines, the extension of the gaps along the azimuthal direction is limited because of photon-photon pair production process. In such gaps, high-energy photons are emitted uniformly and tangentially to the field lines but cannot be efficiently produced along these field lines where the distances to the null charge surface are larger than approx0.9 times the distance of the light cylinder, and the effective azimuth extension of the gaps is about 230 deg. The <span class="hlt">model</span> is applied to the four pulsars, Vela, PSR J1028-5819, PSR J0205+6449, and PSR J2021+3651, whose light curves obtained with Fermi have been recently released. The <span class="hlt">model</span> is successful in reproducing the general feature of the light curves for the four pulsars, and the radial distances of the radio pulse for the four pulsars are estimated.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_15 --> <div id="page_16" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="301"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/23657538','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/23657538"><span id="translatedtitle">Humanised xenograft <span class="hlt">models</span> of bone metastasis <span class="hlt">revisited</span>: novel insights into species-specific mechanisms of cancer cell osteotropism.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Holzapfel, Boris Michael; Thibaudeau, Laure; Hesami, Parisa; Taubenberger, Anna; Holzapfel, Nina Pauline; Mayer-Wagner, Susanne; Power, Carl; Clements, Judith; Russell, Pamela; Hutmacher, Dietmar Werner</p> <p>2013-06-01</p> <p>The determinants and key mechanisms of cancer cell osteotropism have not been identified, mainly due to the lack of reproducible animal <span class="hlt">models</span> representing the biological, genetic and clinical features seen in humans. An ideal <span class="hlt">model</span> should be capable of recapitulating as many steps of the metastatic cascade as possible, thus facilitating the development of prognostic markers and novel therapeutic strategies. Most animal <span class="hlt">models</span> of bone metastasis still have to be derived experimentally as most syngeneic and transgeneic approaches do not provide a robust skeletal phenotype and do not recapitulate the biological processes seen in humans. The xenotransplantation of human cancer cells or tumour tissue into immunocompromised murine hosts provides the possibility to simulate early and late stages of the human disease. Human bone or tissue-engineered human bone constructs can be implanted into the animal to recapitulate more subtle, species-specific aspects of the mutual interaction between human cancer cells and the human bone microenvironment. Moreover, the replication of the entire "organ" bone makes it possible to analyse the interaction between cancer cells and the haematopoietic niche and to confer at least a partial human immunity to the murine host. This process of humanisation is facilitated by novel immunocompromised mouse strains that allow a high engraftment rate of human cells or tissue. These humanised xenograft <span class="hlt">models</span> provide an important research tool to study human biological processes of bone metastasis. PMID:23657538</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JGS....17...61N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JGS....17...61N"><span id="translatedtitle"><span class="hlt">Revisiting</span> the destination ranking procedure in development of an Intervening Opportunities <span class="hlt">Model</span> for public transit trip distribution</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nazem, Mohsen; Trpanier, Martin; Morency, Catherine</p> <p>2015-01-01</p> <p>An Enhanced Intervening Opportunities <span class="hlt">Model</span> (EIOM) is developed for Public Transit (PT). This is a distribution supply dependent <span class="hlt">model</span>, with single constraints on trip production for work trips during morning peak hours (6:00 a.m.-9:00 a.m.) within the Island of Montreal, Canada. Different data sets, including the 2008 Origin-Destination (OD) survey of the Greater Montreal Area, the 2006 Census of Canada, GTFS network data, along with the geographical data of the study area, are used. EIOM is a nonlinear <span class="hlt">model</span> composed of socio-demographics, PT supply data and work location attributes. An enhanced destination ranking procedure is used to calculate the number of spatially cumulative opportunities, the basic variable of EIOM. For comparison, a Basic Intervening Opportunities <span class="hlt">Model</span> (BIOM) is developed by using the basic destination ranking procedure. The main difference between EIOM and BIOM is in the destination ranking procedure: EIOM considers the maximization of a utility function composed of PT Level Of Service and number of opportunities at the destination, along with the OD trip duration, whereas BIOM is based on a destination ranking derived only from OD trip durations. Analysis confirmed that EIOM is more accurate than BIOM. This study presents a new tool for PT analysts, planners and policy makers to study the potential changes in PT trip patterns due to changes in socio-demographic characteristics, PT supply, and other factors. Also it opens new opportunities for the development of more accurate PT demand <span class="hlt">models</span> with new emergent data such as smart card validations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/24384034','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/24384034"><span id="translatedtitle">Protein folding in vivo <span class="hlt">revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Choi, Seong Il; Kwon, Soonbin; Son, Ahyun; Jeong, Hotcherl; Kim, Kyun-Hwan; Seong, Baik L</p> <p>2013-12-01</p> <p>Protein folding in vivo is extremely intricate and challenging to examine or predict because the conformational changes, including folding, misfolding, and aggregation, are largely influenced by the cellular environment. Traditionally, cellular protein folding has been considered predominantly in the context of the Anfinsen postulate and molecular chaperones. However, accumulating evidence reveals that these <span class="hlt">models</span> have limitations. In this review we <span class="hlt">revisit</span> these <span class="hlt">models</span>, and discuss co-translational folding, binding partner-mediated folding, and RNA-mediated folding as alternative or supplementary folding helpers. In addition, we discuss the folding helper systems mediated by macromolecules (e.g., ribosomes, membranes, and prefolded domains in multidomain proteins) that are tightly linked to newly synthesized polypeptides during protein biogenesis. These cis-acting folding helper systems, conceptually different from the trans-acting molecular chaperones, could play a crucial role in protein folding in vivo. Importantly, there is increasing evidence that the surface charges and excluded volume of macromolecules are important factors for stabilizing their connected polypeptides against aggregation. This stabilizing mechanism suggests that macromolecules including RNAs and proteins, let alone molecular chaperones, have an intrinsic ability to exert chaperoning function on their connected polypeptides independent of the linkage type between them. As an effective way to overcome the adverse effect of macromolecular crowding on protein folding, here we suggest that nascent polypeptide chains utilize the crowded environment in favor of productive folding by interacting with macromolecules. PMID:24384034</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19880017774','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19880017774"><span id="translatedtitle">Aeroelastic <span class="hlt">modeling</span> of rotor blades with spanwise variable elastic axis offset: Classic issues <span class="hlt">revisited</span> and new formulations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Bielawa, Richard L.</p> <p>1988-01-01</p> <p>In response to a systematic methodology assessment program directed to the aeroelastic stability of hingeless helicopter rotor blades, improved basic aeroelastic reformulations and new formulations relating to structural sweep were achieved. Correlational results are presented showing the substantially improved performance of the G400 aeroelastic analysis incorporating these new formulations. The formulations pertain partly to sundry solutions to classic problem areas, relating to dynamic inflow with vortex-ring state operation and basic blade kinematics, but mostly to improved physical <span class="hlt">modeling</span> of elastic axis offset (structural sweep) in the presence of nonlinear structural twist. Specific issues addressed are an alternate <span class="hlt">modeling</span> of the delta EI torsional excitation due to compound bending using a force integration approach, and the detailed kinematic representation of an elastically deflected point mass of a beam with both structural sweep and nonlinear twist.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015GeoRL..42.3038D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015GeoRL..42.3038D"><span id="translatedtitle"><span class="hlt">Revisiting</span> the hemispheric asymmetry in midlatitude ozone changes following the Mount Pinatubo eruption: A 3-D <span class="hlt">model</span> study</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dhomse, S. S.; Chipperfield, M. P.; Feng, W.; Hossaini, R.; Mann, G. W.; Santee, M. L.</p> <p>2015-04-01</p> <p>Following the eruption of Mount Pinatubo, satellite and in situ measurements showed a large enhancement in stratospheric aerosol in both hemispheres, but significant midlatitude column O3 depletion was observed only in the north. We use a three-dimensional chemical transport <span class="hlt">model</span> to determine the mechanisms behind this hemispheric asymmetry. The <span class="hlt">model</span>, forced by European Centre for Medium-Range Weather Forecasts ERA-Interim reanalyses and updated aerosol surface area density, successfully simulates observed large column NO2 decreases and the different extents of ozone depletion in the two hemispheres. The chemical ozone loss is similar in the Northern (NH) and Southern Hemispheres (SH), but the contrasting role of dynamics increases the depletion in the NH and decreases it in the SH. The relevant SH dynamics are not captured as well by earlier ERA-40 reanalyses. Overall, the smaller SH column O3 depletion can be attributed to dynamical variability and smaller SH background lower stratosphere O3 concentrations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JChPh.138b5101T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JChPh.138b5101T"><span id="translatedtitle">A coarse-grained <span class="hlt">model</span> for DNA-functionalized spherical colloids, <span class="hlt">revisited</span>: Effective pair potential from parallel replica simulations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Theodorakis, Panagiotis E.; Dellago, Christoph; Kahl, Gerhard</p> <p>2013-01-01</p> <p>We discuss a coarse-grained <span class="hlt">model</span> recently proposed by Starr and Sciortino [J. Phys.: Condens. Matter 18, L347 (2006), 10.1088/0953-8984/18/26/L02] for spherical particles functionalized with short single DNA strands. The <span class="hlt">model</span> incorporates two key aspects of DNA hybridization, i.e., the specificity of binding between DNA bases and the strong directionality of hydrogen bonds. Here, we calculate the effective potential between two DNA-functionalized particles of equal size using a parallel replica protocol. We find that the transition from bonded to unbonded configurations takes place at considerably lower temperatures compared to those that were originally predicted using standard simulations in the canonical ensemble. We put particular focus on DNA-decorations of tetrahedral and octahedral symmetry, as they are promising candidates for the self-assembly into a single-component diamond structure. Increasing colloid size hinders hybridization of the DNA strands, in agreement with experimental findings.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/18642949','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/18642949"><span id="translatedtitle">The CP43 proximal antenna complex of higher plant photosystem II <span class="hlt">revisited</span>: <span class="hlt">modeling</span> and hole burning study. I.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Dang, Nhan C; Zazubovich, Valter; Reppert, Mike; Neupane, Bhanu; Picorel, Rafael; Seibert, Michael; Jankowiak, Ryszard</p> <p>2008-08-14</p> <p>The CP43 core antenna complex of photosystem II is known to possess two quasi-degenerate "red"-trap states (Jankowiak, R. et al. J. Phys. Chem. B 2000, 104, 11805). It has been suggested recently (Zazubovich, V.; Jankowiak, R. J. Lumin. 2007, 127, 245) that the site distribution functions of the red states (A and B) are uncorrelated and that narrow holes are burned in the subpopulations of chlorophylls (Chls) from states A and B that are the lowest-energy Chl in their complex and previously thought not to transfer energy. This <span class="hlt">model</span> of uncorrelated excitation energy transfer (EET) between the quasidegenerate bands is expanded by taking into account both electron-phonon and vibrational coupling. The <span class="hlt">model</span> is applied to fit simultaneously absorption, emission, zero-phonon action, and transient hole burned (HB) spectra obtained for the CP43 complex with minimized contribution from aggregation. It is demonstrated that the above listed spectra can be well-fitted using the uncorrelated EET <span class="hlt">model</span>, providing strong evidence for the existence of efficient energy transfer between the two lowest energy states, A and B (either from A to B or from B to A), in CP43. Possible candidate Chls for the low-energy A and B states are discussed, providing a link between CP43 structure and spectroscopy. Finally, we propose that persistent holes originate from regular NPHB accompanied by the redistribution of oscillator strength due to excitonic interactions, rather than photoconversion involving Chl-protein hydrogen bonding, as suggested before ( Hughes J. L. et al. Biochemistry 2006, 45, 12345 ). In the accompanying paper (Reppert, M.; Zazubovich, V.; Dang, N. C.; Seibert, M.; Jankowiak, R. J. Phys. Chem. B 2008, 9934), it is demonstrated that the <span class="hlt">model</span> discussed in this manuscript is consistent with excitonic calculations, which also provide very good fits to both transient and persistent HB spectra obtained under non-line-narrowing conditions. PMID:18642949</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/20480861','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/20480861"><span id="translatedtitle"><span class="hlt">Revisiting</span> a population-dynamic <span class="hlt">model</span> of air pollution and daily mortality of the elderly in Philadelphia.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Murray, Christian J; Lipfert, Frederick W</p> <p>2010-05-01</p> <p>Epidemiological studies find that elderly, susceptible, and previously impaired individuals are more sensitive to transient air pollution exposures than healthy persons. However, any associated changes in life expectancy remain largely unresolved. Murray and Nelson published a <span class="hlt">model</span> of daily mortality and air pollution that addresses mortality displacement or harvesting by directly considering population dynamics on the basis of the assumption that a period of illness or frailty precedes most elderly deaths. The underlying concept is that a person's response to an environmental exposure also depends on his/her physiological ability to withstand stress at that time. They used Kalman filtering to estimate an unobservable quantity--the size of the frail subpopulation from which elderly (ages > or = 65 yr) nontraumatic deaths are assumed to derive. They found a small subpopulation, relatively robust to environmental variations over 14 yr, with remaining life expectancies of 8-31 days in this frail status. Here, this <span class="hlt">model</span> and dataset are expanded to examine the ramifications in more detail (including seasonality), to consider peak ozone as an additional pollutant, and to consider remaining life expectancies of the this frail subpopulation on a daily basis. Previous studies of mortality displacement and of Philadelphia mortality-air-pollution associations are also summarized in general, and agreement with the Murray-Nelson <span class="hlt">model</span> was found, thus supporting its validity. The estimated additional mortality associated with a given environmental exposure persists for a few days at most but is not always compensated by subsequent mortality deficits. It is concluded that the pollution-associated mortality increases of a few percent in this dataset are consistent with losses of remaining life expectancy of up to a few days. It is also recommended that a more complex population-dynamic <span class="hlt">model</span> be implemented to examine the extent to which previous short-term environmental exposures and seasonal trends may also influence morbidity and thus entry into the frail at-risk subpopulation. PMID:20480861</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015MNRAS.451.2015O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015MNRAS.451.2015O"><span id="translatedtitle"><span class="hlt">Revisiting</span> the rigidly rotating magnetosphere <span class="hlt">model</span> for ? Ori E - II. Magnetic Doppler imaging, arbitrary field RRM, and light variability</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Oksala, M. E.; Kochukhov, O.; Krti?ka, J.; Townsend, R. H. D.; Wade, G. A.; Prvk, M.; Mikulek, Z.; Silvester, J.; Owocki, S. P.</p> <p>2015-08-01</p> <p>The initial success of the Rigidly Rotating Magnetosphere (RRM) <span class="hlt">model</span> application to the B2Vp star ? Ori E by Townsend, Owocki & Groote triggered a renewed era of observational monitoring of this archetypal object. We utilize high-resolution spectropolarimetry and the magnetic Doppler imaging (MDI) technique to simultaneously determine the magnetic configuration, which is predominately dipolar, with a polar strength Bd = 7.3-7.8 kG and a smaller non-axisymmetric quadrupolar contribution, as well as the surface distribution of abundance of He, Fe, C, and Si. We describe a revised RRM <span class="hlt">model</span> that now accepts an arbitrary surface magnetic field configuration, with the field topology from the MDI <span class="hlt">models</span> used as input. The resulting synthetic H ? emission and broad-band photometric observations generally agree with observations, however, several features are poorly fit. To explore the possibility of a photospheric contribution to the observed photometric variability, the MDI abundance maps were used to compute a synthetic photospheric light curve to determine the effect of the surface inhomogeneities. Including the computed photospheric brightness modulation fails to improve the agreement between the observed and computed photometry. We conclude that the discrepancies cannot be explained as an effect of inhomogeneous surface abundance. Analysis of the UV light variability shows good agreement between observed variability and computed light curves, supporting the accuracy of the photospheric light variation calculation. We thus conclude that significant additional physics is necessary for the RRM <span class="hlt">model</span> to acceptably reproduce observations of not only ? Ori E, but also other similar stars with significant stellar wind-magnetic field interactions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2889493','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2889493"><span id="translatedtitle">Integrating evidence from neuroimaging and neuropsychological studies of obsessive-compulsive disorder: The orbitofronto-striatal <span class="hlt">model</span> <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Menzies, Lara; Chamberlain, Samuel R.; Laird, Angela R.; Thelen, Sarah M.; Sahakian, Barbara J.; Bullmore, Ed T.</p> <p>2010-01-01</p> <p>Obsessive-compulsive disorder (OCD) is a common, heritable and disabling neuropsychiatric disorder. Theoretical <span class="hlt">models</span> suggest that OCD is underpinned by functional and structural abnormalities in orbitofronto-striatal circuits. Evidence from cognitive and neuroimaging studies (functional and structural magnetic resonance imaging (MRI) and positron emission tomography (PET)) have generally been taken to be supportive of these theoretical <span class="hlt">models</span>; however, results from these studies have not been entirely congruent with each other. With the advent of whole brain-based structural imaging techniques, such as voxel-based morphometry and multivoxel analyses, we consider it timely to assess neuroimaging findings to date, and to examine their compatibility with cognitive studies and orbitofronto-striatal <span class="hlt">models</span>. As part of this assessment, we performed a quantitative, voxel-level meta-analysis of functional MRI findings, which revealed consistent abnormalities in orbitofronto-striatal and other additional areas in OCD. This review also considers the evidence for involvement of other brain areas outside orbitofronto-striatal regions in OCD, the limitations of current imaging techniques, and how future developments in imaging may aid our understanding of OCD. PMID:18061263</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3385561','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3385561"><span id="translatedtitle">Oculomotor learning <span class="hlt">revisited</span>: a <span class="hlt">model</span> of reinforcement learning in the basal ganglia incorporating an efference copy of motor actions</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Fee, Michale S.</p> <p>2012-01-01</p> <p>In its simplest formulation, reinforcement learning is based on the idea that if an action taken in a particular context is followed by a favorable outcome, then, in the same context, the tendency to produce that action should be strengthened, or reinforced. While reinforcement learning forms the basis of many current theories of basal ganglia (BG) function, these <span class="hlt">models</span> do not incorporate distinct computational roles for signals that convey context, and those that convey what action an animal takes. Recent experiments in the songbird suggest that vocal-related BG circuitry receives two functionally distinct excitatory inputs. One input is from a cortical region that carries context information about the current “time” in the motor sequence. The other is an efference copy of motor commands from a separate cortical brain region that generates vocal variability during learning. Based on these findings, I propose here a general <span class="hlt">model</span> of vertebrate BG function that combines context information with a distinct motor efference copy signal. The signals are integrated by a learning rule in which efference copy inputs gate the potentiation of context inputs (but not efference copy inputs) onto medium spiny neurons in response to a rewarded action. The hypothesis is described in terms of a circuit that implements the learning of visually guided saccades. The <span class="hlt">model</span> makes testable predictions about the anatomical and functional properties of hypothesized context and efference copy inputs to the striatum from both thalamic and cortical sources. PMID:22754501</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014A%26A...569A.123B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014A%26A...569A.123B"><span id="translatedtitle">The blue-edge problem of the V1093 Herculis instability strip <span class="hlt">revisited</span> using evolutionary <span class="hlt">models</span> with atomic diffusion</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bloemen, S.; Hu, H.; Aerts, C.; Dupret, M. A.; stensen, R. H.; Degroote, P.; Mller-Ringat, E.; Rauch, T.</p> <p>2014-09-01</p> <p>We have computed a new grid of evolutionary subdwarf B star (sdB) <span class="hlt">models</span> from the start of central He burning, taking into account atomic diffusion due to radiative levitation, gravitational settling, concentration diffusion, and thermal diffusion. We have computed the non-adiabatic pulsation properties of the <span class="hlt">models</span> and present the predicted p-mode and g-mode instability strips. In previous studies of the sdB instability strips, artificial abundance enhancements of Fe and Ni were introduced in the pulsation driving layers. In our <span class="hlt">models</span>, the abundance enhancements of Fe and Ni occur naturally, eradicating the need to use artificial enhancements. We find that the abundance increases of Fe and Ni were previously underestimated and show that the instability strip predicted by our simulations solves the so-called blue edge problem of the subdwarf B star g-mode instability strip. The hottest known g-mode pulsator, KIC 10139564, now resides well within the instability strip even when only modes with low spherical degrees (l ? 2) are considered. Appendix A is available in electronic form at http://www.aanda.org</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2710023','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2710023"><span id="translatedtitle">Magainin 2 <span class="hlt">Revisited</span>: A Test of the Quantitative <span class="hlt">Model</span> for the All-or-None Permeabilization of Phospholipid Vesicles</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Gregory, Sonia M.; Pokorny, Antje; Almeida, Paulo F.F.</p> <p>2009-01-01</p> <p>Abstract The all-or-none kinetic <span class="hlt">model</span> that we recently proposed for the antimicrobial peptide cecropin A is tested here for magainin 2. In mixtures of phosphatidylcholine (PC)/phosphatidylglycerol (PG) 50:50 and 70:30, release of contents from lipid vesicles occurs in an all-or-none fashion and the differences between PC/PG 50:50 and 70:30 can be ascribed mainly to differences in binding, which was determined independently and is ∼20 times greater to PC/PG 50:50 than to 70:30. Only one variable parameter, β, corresponding to the ratio of the rates of pore opening to pore closing, is used to fit dye release kinetics from these two mixtures, for several peptide/lipid ratios ranging from 1:25 to 1:200. However, unlike for cecropin A where it stays almost constant, β increases five times as the PG content of the vesicles increases from 30 to 50%. Thus, magainin 2 is more sensitive to anionic lipid content than cecropin A. But overall, magainin follows the same all-or-none kinetic <span class="hlt">model</span> as cecropin A in these lipid mixtures, with slightly different parameter values. When the PG content is reduced to 20 mol %, dye release becomes very low; the mechanism appears to change, and is consistent with a graded kinetic <span class="hlt">model</span>. We suggest that the peptide may be inducing formation of PG domains. In either mechanism, no peptide oligomerization occurs and magainin catalyzes dye release in proportion to its concentration on the membrane in a peptide state that we call a pore. We envision this structure as a chaotic or stochastic type of pore, involving both lipids and peptides, not a well-defined, peptide-lined channel. PMID:19134472</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4690123','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4690123"><span id="translatedtitle">Risk Assessment of Deoxynivalenol by <span class="hlt">Revisiting</span> Its Bioavailability in Pig and Rat <span class="hlt">Models</span> to Establish Which Is More Suitable</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Saint-Cyr, Manuel Jimmy; Perrin-Guyomard, Agnès; Manceau, Jacqueline; Houée, Paméla; Delmas, Jean-Michel; Rolland, Jean-Guy; Laurentie, Michel</p> <p>2015-01-01</p> <p>Due to its toxic properties, high stability, and prevalence, the presence of deoxynivalenol (DON) in the food chain is a major threat to food safety and therefore a health risk for both humans and animals. In this study, experiments were carried out with sows and female rats to examine the kinetics of DON after intravenous and oral administration at 100 µg/kg of body weight. After intravenous administration of DON in pigs, a two-compartment <span class="hlt">model</span> with rapid initial distribution (0.030 ± 0.019 h) followed by a slower terminal elimination phase (1.53 ± 0.54 h) was fitted to the concentration profile of DON in pig plasma. In rats, a short elimination half-life (0.46 h) and a clearance of 2.59 L/h/kg were estimated by sparse sampling non-compartmental analysis. Following oral exposure, DON was rapidly absorbed and reached maximal plasma concentrations (Cmax) of 42.07 ± 8.48 and 10.44 ± 5.87 µg/L plasma after (tmax) 1.44 ± 0.52 and 0.17 h in pigs and rats, respectively. The mean bioavailability of DON was 70.5% ± 25.6% for pigs and 47.3% for rats. In the framework of DON risk assessment, these two animal <span class="hlt">models</span> could be useful in an exposure scenario in two different ways because of their different bioavailability. PMID:26633505</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26633505','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26633505"><span id="translatedtitle">Risk Assessment of Deoxynivalenol by <span class="hlt">Revisiting</span> Its Bioavailability in Pig and Rat <span class="hlt">Models</span> to Establish Which Is More Suitable.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Saint-Cyr, Manuel Jimmy; Perrin-Guyomard, Agns; Manceau, Jacqueline; Houe, Pamla; Delmas, Jean-Michel; Rolland, Jean-Guy; Laurentie, Michel</p> <p>2015-01-01</p> <p>Due to its toxic properties, high stability, and prevalence, the presence of deoxynivalenol (DON) in the food chain is a major threat to food safety and therefore a health risk for both humans and animals. In this study, experiments were carried out with sows and female rats to examine the kinetics of DON after intravenous and oral administration at 100 g/kg of body weight. After intravenous administration of DON in pigs, a two-compartment <span class="hlt">model</span> with rapid initial distribution (0.030 0.019 h) followed by a slower terminal elimination phase (1.53 0.54 h) was fitted to the concentration profile of DON in pig plasma. In rats, a short elimination half-life (0.46 h) and a clearance of 2.59 L/h/kg were estimated by sparse sampling non-compartmental analysis. Following oral exposure, DON was rapidly absorbed and reached maximal plasma concentrations (Cmax) of 42.07 8.48 and 10.44 5.87 g/L plasma after (tmax) 1.44 0.52 and 0.17 h in pigs and rats, respectively. The mean bioavailability of DON was 70.5% 25.6% for pigs and 47.3% for rats. In the framework of DON risk assessment, these two animal <span class="hlt">models</span> could be useful in an exposure scenario in two different ways because of their different bioavailability. PMID:26633505</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ClDy..tmp..359L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ClDy..tmp..359L"><span id="translatedtitle">Observational constraints on atmospheric and oceanic cross-equatorial heat transports: <span class="hlt">revisiting</span> the precipitation asymmetry problem in climate <span class="hlt">models</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Loeb, Norman G.; Wang, Hailan; Cheng, Anning; Kato, Seiji; Fasullo, John T.; Xu, Kuan-Man; Allan, Richard P.</p> <p>2015-08-01</p> <p>Satellite based top-of-atmosphere (TOA) and surface radiation budget observations are combined with mass corrected vertically integrated atmospheric energy divergence and tendency from reanalysis to infer the regional distribution of the TOA, atmospheric and surface energy budget terms over the globe. Hemispheric contrasts in the energy budget terms are used to determine the radiative and combined sensible and latent heat contributions to the cross-equatorial heat transports in the atmosphere (AHTEQ) and ocean (OHTEQ). The contrast in net atmospheric radiation implies an AHTEQ from the northern hemisphere (NH) to the southern hemisphere (SH) (0.75 PW), while the hemispheric difference in sensible and latent heat implies an AHTEQ in the opposite direction (0.51 PW), resulting in a net NH to SH AHTEQ (0.24 PW). At the surface, the hemispheric contrast in the radiative component (0.95 PW) dominates, implying a 0.44 PW SH to NH OHTEQ. Coupled <span class="hlt">model</span> intercomparison project phase 5 (CMIP5) <span class="hlt">models</span> with excessive net downward surface radiation and surface-to-atmosphere sensible and latent heat transport in the SH relative to the NH exhibit anomalous northward AHTEQ and overestimate SH tropical precipitation. The hemispheric bias in net surface radiative flux is due to too much longwave surface radiative cooling in the NH tropics in both clear and all-sky conditions and excessive shortwave surface radiation in the SH subtropics and extratropics due to an underestimation in reflection by clouds.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016MNRAS.tmp..105B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016MNRAS.tmp..105B"><span id="translatedtitle">Active Binary R Arae <span class="hlt">Revisited</span>: Bringing the Secondary Component to Light and Physical <span class="hlt">Modeling</span> of the Circumstellar Material</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bak??, H.; Bak??, V.; Eker, Z.; Demircan, O.</p> <p>2016-02-01</p> <p>The spectral lines of the secondary component of the active binary system R Ara were uncovered for the first time, which allowed directly to determine the parameters of the spectroscopic orbit. The mass ratio of the system is updated to a new observational value of M2/M1 = 0.305 0.005 which is 20 per cent smaller than the literature value (M2/M1 = 0.39). <span class="hlt">Modeling</span> the reconstructed component spectra yielded the equatorial rotational velocities of the components as vrot1 = 202 km/s and vrot2 = 73 km/s indicating a very fast rotation (5 times faster than the synchronous rotation velocity) for the primary and synchronous rotation for the secondary component. The circumstellar material in the system was investigated using the Hipparcos satellite data and the high resolution (R 41000) spectral data. According to our <span class="hlt">model</span>, there is always material transferring from the secondary component onto the primary causing a hot region on its surface. The structural difference between the spectra taken at the same orbital phase but at different epochs proved that the density and the velocity of the transferring material are variable. There are three main trends in the light curve and spectral line variations suggesting the activity cycles for the system, namely quiescent, moderate and active cycles. It was estimated that the circumstellar material around could be extended to large distances up to 40 R? from the system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22096856','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22096856"><span id="translatedtitle">On Monte Carlo <span class="hlt">modeling</span> of megavoltage photon beams: A <span class="hlt">revisited</span> study on the sensitivity of beam parameters</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Chibani, Omar; Moftah, Belal; Ma, C.-M. Charlie</p> <p>2011-01-15</p> <p>Purpose: To commission Monte Carlo beam <span class="hlt">models</span> for five Varian megavoltage photon beams (4, 6, 10, 15, and 18 MV). The goal is to closely match measured dose distributions in water for a wide range of field sizes (from 2x2 to 35x35 cm{sup 2}). The second objective is to reinvestigate the sensitivity of the calculated dose distributions to variations in the primary electron beam parameters. Methods: The GEPTS Monte Carlo code is used for photon beam simulations and dose calculations. The linear accelerator geometric <span class="hlt">models</span> are based on (i) manufacturer specifications, (ii) corrections made by Chibani and Ma [''On the discrepancies between Monte Carlo dose calculations and measurements for the 18 MV Varian photon beam,'' Med. Phys. 34, 1206-1216 (2007)], and (iii) more recent drawings. Measurements were performed using pinpoint and Farmer ionization chambers, depending on the field size. Phase space calculations for small fields were performed with and without angle-based photon splitting. In addition to the three commonly used primary electron beam parameters (E{sub AV} is the mean energy, FWHM is the energy spectrum broadening, and R is the beam radius), the angular divergence ({theta}) of primary electrons is also considered. Results: The calculated and measured dose distributions agreed to within 1% local difference at any depth beyond 1 cm for different energies and for field sizes varying from 2x2 to 35x35 cm{sup 2}. In the penumbra regions, the distance to agreement is better than 0.5 mm, except for 15 MV (0.4-1 mm). The measured and calculated output factors agreed to within 1.2%. The 6, 10, and 18 MV beam <span class="hlt">models</span> use {theta}=0 deg., while the 4 and 15 MV beam <span class="hlt">models</span> require {theta}=0.5 deg. and 0.6 deg., respectively. The parameter sensitivity study shows that varying the beam parameters around the solution can lead to 5% differences with measurements for small (e.g., 2x2 cm{sup 2}) and large (e.g., 35x35 cm{sup 2}) fields, while a perfect agreement is maintained for the 10x10 cm{sup 2} field. The influence of R on the central-axis depth dose and the strong influence of {theta} on the lateral dose profiles are demonstrated. Conclusions: Dose distributions for very small and very large fields were proved to be more sensitive to variations in E{sub AV}, R, and {theta} in comparison with the 10x10 cm{sup 2} field. Monte Carlo beam <span class="hlt">models</span> need to be validated for a wide range of field sizes including small field sizes (e.g., 2x2 cm{sup 2}).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EOSTr..93Q.520B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EOSTr..93Q.520B"><span id="translatedtitle">Satellite failures <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Balcerak, Ernie</p> <p>2012-12-01</p> <p>In January 1994, the two geostationary satellites known as Anik-E1 and Anik-E2, operated by Telesat Canada, failed one after the other within 9 hours, leaving many northern Canadian communities without television and data services. The outage, which shut down much of the country's broadcast television for hours and cost Telesat Canada more than $15 million, generated significant media attention. Lam et al. used publicly available records to <span class="hlt">revisit</span> the event; they looked at failure details, media coverage, recovery effort, and cost. They also used satellite and ground data to determine the precise causes of those satellite failures. The researchers traced the entire space weather event from conditions on the Sun through the interplanetary medium to the particle environment in geostationary orbit.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/16132203','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/16132203"><span id="translatedtitle">The Nelson's syndrome... <span class="hlt">revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Assié, Guillaume; Bahurel, Hélène; Bertherat, Jérôme; Kujas, Michèle; Legmann, Paul; Bertagna, Xavier</p> <p>2004-01-01</p> <p>Adrenalectomy is a radical therapeutic approach to control hypercortisolism in some patients with Cushing's disease. However it may be complicated by the Nelson's syndrome, defined by the association of a pituitary macroadenoma and high ACTH secretion after adrenalectomy. This definition has not changed since the end of the fifties. Today the Nelson's syndrome must be <span class="hlt">revisited</span> with new to criteria using more sensitive diagnostic tools, especially the pituitary magnetic resonance imaging. In this paper we will review the pathophysiological aspects of corticotroph tumor growth, with reference to the impact of adrenalectomy. The main epidemiological data on the Nelson's syndrome will be presented. More importantly, we will propose a new pathophysiological and practical approach to this question which attempts to evaluate the Corticotroph Tumor Progression after adrenalectomy, rather than to diagnose the Nelson's syndrome. We will discuss the consequences for the management of Cushing's disease patients after adrenalectomy, and will also draw some perspectives. PMID:16132203</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_16 --> <div id="page_17" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="321"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26240384','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26240384"><span id="translatedtitle"><span class="hlt">Revisiting</span> the structure/function relationships of H/ACA(-like) RNAs: a unified <span class="hlt">model</span> for Euryarchaea and Crenarchaea.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Toffano-Nioche, Claire; Gautheret, Daniel; Leclerc, Fabrice</p> <p>2015-09-18</p> <p>A structural and functional classification of H/ACA and H/ACA-like motifs is obtained from the analysis of the H/ACA guide RNAs which have been identified previously in the genomes of Euryarchaea (Pyrococcus) and Crenarchaea (Pyrobaculum). A unified structure/function <span class="hlt">model</span> is proposed based on the common structural determinants shared by H/ACA and H/ACA-like motifs in both Euryarchaea and Crenarchaea. Using a computational approach, structural and energetic rules for the guide:target RNA-RNA interactions are derived from structural and functional data on the H/ACA RNP particles. H/ACA(-like) motifs found in Pyrococcus are evaluated through the classification and their biological relevance is discussed. Extra-ribosomal targets found in both Pyrococcus and Pyrobaculum might support the hypothesis of a gene regulation mediated by H/ACA(-like) guide RNAs in archaea. PMID:26240384</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013PhRvD..87e4004B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013PhRvD..87e4004B"><span id="translatedtitle">Self-bound quark matter in the NJL <span class="hlt">model</span> <span class="hlt">revisited</span>: From schematic droplets to domain-wall solitons</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Buballa, Michael; Carignano, Stefano</p> <p>2013-03-01</p> <p>The existence and the properties of self-bound quark matter in the Nambu-Jona-Lasinio <span class="hlt">model</span> at zero temperature are investigated in the mean-field approximation, focusing on inhomogeneous structures with one-dimensional spatial modulations. It is found that the most stable homogeneous solutions which have previously been interpreted as schematic quark droplets are unstable against the formation of a one-dimensional lattice of domain-wall solitons. The solitons repel each other, so that the minimal energy per quark is realized in the single-soliton limit. The properties of the solitons and their interactions are discussed in detail, and the effect of vector interactions is estimated. The results may be relevant for the dynamics of expanding quark matter.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4652768','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4652768"><span id="translatedtitle"><span class="hlt">Revisiting</span> the structure/function relationships of H/ACA(-like) RNAs: a unified <span class="hlt">model</span> for Euryarchaea and Crenarchaea</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Toffano-Nioche, Claire; Gautheret, Daniel; Leclerc, Fabrice</p> <p>2015-01-01</p> <p>A structural and functional classification of H/ACA and H/ACA-like motifs is obtained from the analysis of the H/ACA guide RNAs which have been identified previously in the genomes of Euryarchaea (Pyrococcus) and Crenarchaea (Pyrobaculum). A unified structure/function <span class="hlt">model</span> is proposed based on the common structural determinants shared by H/ACA and H/ACA-like motifs in both Euryarchaea and Crenarchaea. Using a computational approach, structural and energetic rules for the guide:target RNA-RNA interactions are derived from structural and functional data on the H/ACA RNP particles. H/ACA(-like) motifs found in Pyrococcus are evaluated through the classification and their biological relevance is discussed. Extra-ribosomal targets found in both Pyrococcus and Pyrobaculum might support the hypothesis of a gene regulation mediated by H/ACA(-like) guide RNAs in archaea. PMID:26240384</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015SPIE.9646E..05M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015SPIE.9646E..05M"><span id="translatedtitle"><span class="hlt">Revisiting</span> Intel Xeon Phi optimization of Thompson cloud microphysics scheme in Weather Research and Forecasting (WRF) <span class="hlt">model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mielikainen, Jarno; Huang, Bormin; Huang, Allen</p> <p>2015-10-01</p> <p>The Thompson cloud microphysics scheme is a sophisticated cloud microphysics scheme in the Weather Research and Forecasting (WRF) <span class="hlt">model</span>. The scheme is very suitable for massively parallel computation as there are no interactions among horizontal grid points. Compared to the earlier microphysics schemes, the Thompson scheme incorporates a large number of improvements. Thus, we have optimized the speed of this important part of WRF. Intel Many Integrated Core (MIC) ushers in a new era of supercomputing speed, performance, and compatibility. It allows the developers to run code at trillions of calculations per second using the familiar programming <span class="hlt">model</span>. In this paper, we present our results of optimizing the Thompson microphysics scheme on Intel Many Integrated Core Architecture (MIC) hardware. The Intel Xeon Phi coprocessor is the first product based on Intel MIC architecture, and it consists of up to 61 cores connected by a high performance on-die bidirectional interconnect. The coprocessor supports all important Intel development tools. Thus, the development environment is familiar one to a vast number of CPU developers. Although, getting a maximum performance out of MICs will require using some novel optimization techniques. New optimizations for an updated Thompson scheme are discusses in this paper. The optimizations improved the performance of the original Thompson code on Xeon Phi 7120P by a factor of 1.8x. Furthermore, the same optimizations improved the performance of the Thompson on a dual socket configuration of eight core Intel Xeon E5-2670 CPUs by a factor of 1.8x compared to the original Thompson code.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013Nanos...511919L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013Nanos...511919L"><span id="translatedtitle"><span class="hlt">Revisiting</span> catalytic <span class="hlt">model</span> reaction p-nitrophenol/NaBH4 using metallic nanoparticles coated on polymeric spheres</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, Maolin; Chen, Guofang</p> <p>2013-11-01</p> <p>The early reported pseudo-first-order reaction kinetics of the polymer-supported metallic nanocatalysts for the <span class="hlt">model</span> reaction of p-nitrophenol (p-NP)/NaBH4 were probably oversimplified. Here a detailed study of p-NP reduction by NaBH4 in the presence of the raspberry-like poly(allylamine hydrochloride)-modified polymer poly(glycidyl methacrylate) composite sub-microspheres with tunable gold nanoparticles (PGMA@PAH@AuNPs) was presented. Effects of polyelectrolyte concentration, the ratio of polymer spheres to gold nanoparticles, and the solution pH value for composite synthesis on the induction period, reaction time, average reaction rate and average turnover frequency were systematically investigated. Experimental results in all cases of our study revealed an nth order (n > 1) of the p-NP/NaBH4 catalytic reaction by the prepared polymer composite particles. The apparent order of reaction, n, is dependent on the total surface area of the coated gold nanoparticles on the polymer spheres, which can be closely correlated with the tunable gold nanoparticle surface coverage. The mechanism of the observed catalytic activity enhancement was proposed based on active epoxy groups of the polymer spheres and a large adsorption of p-nitrophenolate anions onto the positively-charged spheres.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JHEP...05..036B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JHEP...05..036B"><span id="translatedtitle">Higgs portal vector dark matter: <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Baek, Seungwon; Ko, P.; Park, Wan-Il; Senaha, Eibun</p> <p>2013-05-01</p> <p>We <span class="hlt">revisit</span> the Higgs portal vector dark matter <span class="hlt">model</span> including a hidden sector Higgs field that generates the mass of the vector dark matter. The <span class="hlt">model</span> becomes renormalizable and has two scalar bosons, the mixtures of the standard <span class="hlt">model</span> (SM) Higgs and the hidden sector Higgs bosons. The strong bound from direct detection such as XENON100 is evaded due to the cancellation mechanism between the contributions from two scalar bosons. As a result, the <span class="hlt">model</span> becomes still viable in large range of dark matter mass, contrary to some claims in the literature. The Higgs properties are also affected, the signal strengths for the Higgs boson search being universally suppressed relative to the SM value, which could be tested at the LHC in the future.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26332541','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26332541"><span id="translatedtitle"><span class="hlt">Revisiting</span> Buruli ulcer.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Yotsu, Rie R; Murase, Chiaki; Sugawara, Mariko; Suzuki, Koichi; Nakanaga, Kazue; Ishii, Norihisa; Asiedu, Kingsley</p> <p>2015-11-01</p> <p>Buruli ulcer (BU), or Mycobacterium ulcerans infection, is a new emerging infectious disease which has been reported in over 33 countries worldwide. It has been noted not only in tropical areas, such as West Africa where it is most endemic, but also in moderate non-tropical climate areas, including Australia and Japan. Clinical presentation starts with a papule, nodule, plaque or edematous form which eventually leads to extensive skin ulceration. It can affect all age groups, but especially children aged between 5 and 15years in West Africa. Multiple-antibiotic treatment has proven effective, and with surgical intervention at times of severity, it is curable. However, if diagnosis and treatment is delayed, those affected may be left with life-long disabilities. The disease is not yet fully understood, including its route of transmission and pathogenesis. However, due to recent research, several important features of the disease are now being elucidated. Notably, there may be undiagnosed cases in other parts of the world where BU has not yet been reported. Japan exemplifies the finding that awareness among dermatologists plays a key role in BU case detection. So, what about in other countries where a case of BU has never been diagnosed and there is no awareness of the disease among the population or, more importantly, among health professionals? This article will <span class="hlt">revisit</span> BU, reviewing clinical features as well as the most recent epidemiological and scientific findings of the disease, to raise awareness of BU among dermatologists worldwide. PMID:26332541</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009LNCS.5848..104S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009LNCS.5848..104S"><span id="translatedtitle">Twin Signature Schemes, <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schäge, Sven</p> <p></p> <p>In this paper, we <span class="hlt">revisit</span> the twin signature scheme by Naccache, Pointcheval and Stern from CCS 2001 that is secure under the Strong RSA (SRSA) assumption and improve its efficiency in several ways. First, we present a new twin signature scheme that is based on the Strong Diffie-Hellman (SDH) assumption in bilinear groups and allows for very short signatures and key material. A big advantage of this scheme is that, in contrast to the original scheme, it does not require a computationally expensive function for mapping messages to primes. We prove this new scheme secure under adaptive chosen message attacks. Second, we present a modification that allows to significantly increase efficiency when signing long messages. This construction uses collision-resistant hash functions as its basis. As a result, our improvements make the signature length independent of the message size. Our construction deviates from the standard hash-and-sign approach in which the hash value of the message is signed in place of the message itself. We show that in the case of twin signatures, one can exploit the properties of the hash function as an integral part of the signature scheme. This improvement can be applied to both the SRSA based and SDH based twin signature scheme.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JSeis..19..231V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JSeis..19..231V"><span id="translatedtitle">Moment tensor decompositions <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vavry?uk, Vclav</p> <p>2015-01-01</p> <p>The decomposition of moment tensors into isotropic (ISO), double-couple (DC) and compensated linear vector dipole (CLVD) components is a tool for classifying and physically interpreting seismic sources. Since an increasing quantity and quality of seismic data allow inverting for accurate moment tensors and interpreting details of the source process, an efficient and physically reasonable decomposition of moment and source tensors is necessary. In this paper, the most common moment tensor decompositions are <span class="hlt">revisited</span>, new equivalent formulas of the decompositions are derived, suitable norms of the moment tensors are discussed and the properties of commonly used source-type plots are analysed. The Hudson skewed diamond plot is introduced in a much simpler way than originally proposed. It is shown that not only the Hudson plot but also the diamond CLVD-ISO plot and the Riedesel-Jordan plot conserve the uniform distribution probability of moment eigenvalues if the appropriate norm of moment tensors is applied. When analysing moment tensor uncertainties, no source-type plot is clearly preferable. Since the errors in the eigenvectors and eigenvalues of the moment tensors cannot be easily separated, the moment tensor uncertainties project into the source-type plots in a complicated way. As a consequence, the moment tensors with the same uncertainties project into clusters of a different size. In case of an anisotropic focal area, the complexity of moment tensors of earthquakes prevents their direct interpretation, and the decomposition of moment tensors must be substituted by that of the source tensors.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011APS..DFDM27001Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011APS..DFDM27001Y"><span id="translatedtitle">Streaming potential <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yariv, Ehud; Schnitzer, Ory; Frankel, Itzchak</p> <p>2011-11-01</p> <p>Streaming-potential phenomena refer to the generation of bulk electric fields by imposed relative motion between a charged solid and the Debye layer adjacent to it. Realistic scenarios are adequately described by the thin-Debye-layer limit ? --> 0 (? denoting the dimensionless Debye thickness), which has been addressed by Cox (1997). Cox's analysis has established that the perturbation to the flow, neglected in the earlier investigations, gives rise to an O (?4) force that dominates that contributed by Maxwell stresses. Cox's theory is founded upon the assumption of O (1) Hartmann and Pclet numbers. We demonstrate that the product of these numbers is actually O (?-2) and accordingly <span class="hlt">revisit</span> the generic problem of streaming-potential. Electric-current matching between the Debye layer and the bulk provides an inhomogeneous Neumann condition governing the electric field in the latter. This field, in turn, results in a velocity perturbation animated by a Smoluchowski-type slip condition. Owing to dominant convection, the present analysis yields an asymptotic structure considerably simpler than that of Cox (1997): the electro-viscous effect now already appears at O (?2) and is contributed by both Maxwell and viscous stresses. The present paradigm is illustrated for the prototypic problem of a sphere sedimenting in an unbounded fluid, with the resulting drag correction differing from that calculated by Cox (1997).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4260746','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4260746"><span id="translatedtitle"><span class="hlt">Revisiting</span> caspases in sepsis</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Aziz, M; Jacob, A; Wang, P</p> <p>2014-01-01</p> <p>Sepsis is a life-threatening illness that occurs due to an abnormal host immune network which extends through the initial widespread and overwhelming inflammation, and culminates at the late stage of immunosupression. Recently, interest has been shifted toward therapies aimed at reversing the accompanying periods of immune suppression. Studies in experimental animals and critically ill patients have demonstrated that increased apoptosis of lymphoid organs and some parenchymal tissues contributes to this immune suppression, anergy and organ dysfunction. Immediate to the discoveries of the intracellular proteases, caspases for the induction of apoptosis and inflammation, and their striking roles in sepsis have been focused elaborately in a number of original and review articles. Here we <span class="hlt">revisited</span> the different aspects of caspases in terms of apoptosis, pyroptosis, necroptosis and inflammation and focused their links in sepsis by reviewing several recent findings. In addition, we have documented striking perspectives which not only rewrite the pathophysiology, but also modernize our understanding for developing novel therapeutics against sepsis. PMID:25412304</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25412304','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25412304"><span id="translatedtitle"><span class="hlt">Revisiting</span> caspases in sepsis.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Aziz, M; Jacob, A; Wang, P</p> <p>2014-01-01</p> <p>Sepsis is a life-threatening illness that occurs due to an abnormal host immune network which extends through the initial widespread and overwhelming inflammation, and culminates at the late stage of immunosupression. Recently, interest has been shifted toward therapies aimed at reversing the accompanying periods of immune suppression. Studies in experimental animals and critically ill patients have demonstrated that increased apoptosis of lymphoid organs and some parenchymal tissues contributes to this immune suppression, anergy and organ dysfunction. Immediate to the discoveries of the intracellular proteases, caspases for the induction of apoptosis and inflammation, and their striking roles in sepsis have been focused elaborately in a number of original and review articles. Here we <span class="hlt">revisited</span> the different aspects of caspases in terms of apoptosis, pyroptosis, necroptosis and inflammation and focused their links in sepsis by reviewing several recent findings. In addition, we have documented striking perspectives which not only rewrite the pathophysiology, but also modernize our understanding for developing novel therapeutics against sepsis. PMID:25412304</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JSV...333.1767T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JSV...333.1767T"><span id="translatedtitle"><span class="hlt">Revisiting</span> a magneto-elastic strange attractor</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tam, Jee Ian; Holmes, Philip</p> <p>2014-03-01</p> <p>We <span class="hlt">revisit</span> an early example of a nonlinear oscillator that exhibits chaotic motions when subjected to periodic excitation: the magneto-elastically buckled beam. In the paper of Moons and Holmes (1980) [1] magnetic field calculations were outlined but not carried through; instead the nonlinear forces responsible for creation of a two-well potential and buckling were fitted to a polynomial function after reduction to a single mode <span class="hlt">model</span>. In the present paper we compute the full magnetic field and use it to approximate the forces acting on the beam, also using a single mode reduction. This provides a complete <span class="hlt">model</span> that accurately predicts equilibria, bifurcations, and free oscillation frequencies of an experimental device. We also compare some periodic, transient and chaotic motions with those obtained by numerical simulations of the single mode <span class="hlt">model</span>, further illustrating the rich dynamical behavior of this simple electromechanical system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=oil&pg=3&id=EJ1016988','ERIC'); return false;" href="http://eric.ed.gov/?q=oil&pg=3&id=EJ1016988"><span id="translatedtitle">The "Mushroom Cloud" Demonstration <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Panzarasa, Guido; Sparnacci, Katia</p> <p>2013-01-01</p> <p>A <span class="hlt">revisitation</span> of the classical "mushroom cloud" demonstration is described. Instead of aniline and benzoyl peroxide, the proposed reaction involves household chemicals such as alpha-pinene (turpentine oil) and trichloroisocyanuric acid ("Trichlor") giving an impressive demonstration of oxidation and combustion reactions that</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=chemical+AND+reactions&pg=5&id=EJ1016988','ERIC'); return false;" href="http://eric.ed.gov/?q=chemical+AND+reactions&pg=5&id=EJ1016988"><span id="translatedtitle">The "Mushroom Cloud" Demonstration <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Panzarasa, Guido; Sparnacci, Katia</p> <p>2013-01-01</p> <p>A <span class="hlt">revisitation</span> of the classical "mushroom cloud" demonstration is described. Instead of aniline and benzoyl peroxide, the proposed reaction involves household chemicals such as alpha-pinene (turpentine oil) and trichloroisocyanuric acid ("Trichlor") giving an impressive demonstration of oxidation and combustion reactions that…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhRvB..91h1102Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhRvB..91h1102Z"><span id="translatedtitle">Dynamical spin structure factor of one-dimensional interacting fermions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zyuzin, Vladimir A.; Maslov, Dmitrii L.</p> <p>2015-02-01</p> <p>We <span class="hlt">revisit</span> the dynamic spin susceptibility ? (q ,? ) of one-dimensional interacting fermions. To second order in the interaction, backscattering results in a logarithmic correction to ? (q ,? ) at q ?kF , even if the single-particle spectrum is linearized near the Fermi points. Consequently, the dynamic spin structure factor Im ? (q ,? ) is nonzero at frequencies above the single-particle continuum. In the boson language, this effect results from the marginally irrelevant backscattering operator of the <span class="hlt">sine-Gordon</span> <span class="hlt">model</span>. Away from the threshold, the high-frequency tail of Im ? (q ,? ) due to backscattering is larger than that due to finite mass by a factor of kF/q . We derive the renormalization group equations for the coupling constants of the g -ology <span class="hlt">model</span> at finite ? and q and find the corresponding expression for ? (q ,? ) , valid to all orders in the interaction but not in the immediate vicinity of the continuum boundary, where the finite-mass effects become dominant.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25384602','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25384602"><span id="translatedtitle">Oxidative phosphorylation <span class="hlt">revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Nath, Sunil; Villadsen, John</p> <p>2015-03-01</p> <p>The fundamentals of oxidative phosphorylation and photophosphorylation are <span class="hlt">revisited</span>. New experimental data on the involvement of succinate and malate anions respectively in oxidative phosphorylation and photophosphorylation are presented. These new data offer a novel molecular mechanistic explanation for the energy coupling and ATP synthesis carried out in mitochondria and chloroplast thylakoids. The mechanism does not suffer from the flaws in Mitchell's chemiosmotic theory that have been pointed out in many studies since its first appearance 50 years ago, when it was hailed as a ground-breaking mechanistic explanation of what is perhaps the most important process in cellular energetics. The new findings fit very well with the predictions of Nath's torsional mechanism of energy transduction and ATP synthesis. It is argued that this mechanism, based on at least 15 years of experimental and theoretical work by Sunil Nath, constitutes a fundamentally different theory of the energy conversion process that eliminates all the inconsistencies in Mitchell's chemiosmotic theory pointed out by other authors. It is concluded that the energy-transducing complexes in oxidative phosphorylation and photosynthesis are proton-dicarboxylic acid anion cotransporters and not simply electrogenic proton translocators. These results necessitate revision of previous theories of biological energy transduction, coupling, and ATP synthesis. The novel molecular mechanism is extended to cover ATP synthesis in prokaryotes, in particular to alkaliphilic and haloalkaliphilic bacteria, essentially making it a complete theory addressing mechanistic, kinetic, and thermodynamic details. Finally, based on the new interpretation of oxidative phosphorylation, quantitative values for the P/O ratio, the amount of ATP generated per redox package of the reduced substrates, are calculated and compared with experimental values for fermentation on different substrates. It is our hope that the presentation of oxidative phosphorylation and photophosphorylation from a wholly new perspective will rekindle scientific discussion of a key process in bioenergetics and catalyze new avenues of research in a truly interdisciplinary field. PMID:25384602</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ccrg.book..279I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ccrg.book..279I"><span id="translatedtitle">Complexity and Control in Solitary Conductive PDEs</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ivancevic, Vladimir G.; Reid, Darryn J.</p> <p>2015-11-01</p> <p>In this Chapter, we review and analyze <span class="hlt">models</span> of controlled complexity in nonlinear pulse conduction, ranging from the Hodgkin-Huxley action potentials propagating along neural fibers to rogue waves in optical fibers. The novel <span class="hlt">model</span> proposed is an alternative to the Hodgkin-Huxley neural <span class="hlt">model</span> in the form of the <span class="hlt">sine-Gordon</span> wave equation. This new alternative explains pulse conduction in terms of general wave phenomena (such as kinks, solitons and breathers).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/27002506','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/27002506"><span id="translatedtitle"><span class="hlt">Revisiting</span> dosing regimen using PK/PD <span class="hlt">modeling</span>: the <span class="hlt">MODEL</span>1 phase I/II trial of docetaxel plus epirubicin in metastatic breast cancer patients.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hénin, Emilie; Meille, Christophe; Barbolosi, Dominique; You, Benoit; Guitton, Jérôme; Iliadis, Athanassios; Freyer, Gilles</p> <p>2016-04-01</p> <p>The <span class="hlt">MODEL</span>1 trial is the first <span class="hlt">model</span>-driven phase I/II dose-escalation study of densified docetaxel plus epirubicin administration in metastatic breast cancer patients, a regimen previously known to induce unacceptable life-threatening toxicities. The primary objective was to determine the maximum tolerated dose of this densified regimen. Study of the efficacy was a secondary objective. Her2-negative, hormone-resistant metastatic breast cancer patients were treated with escalating doses of docetaxel plus epirubicin every 2 weeks for six cycles with granulocyte colony stimulating factor support. A total of 16 patients were treated with total doses ranging from 85 to 110 mg of docetaxel plus epirubicin per cycle. Dose escalation was controlled by a non-hematological toxicity <span class="hlt">model</span>. Dose densification was guided by a <span class="hlt">model</span> of neutrophil kinetics, able to optimize docetaxel plus epirubicin dosing with respect to pre-defined acceptable levels of hematological toxicity while ensuring maximal efficacy. The densified treatment was safe since hematological toxicity was much lower compared to previous findings, and other adverse events were consistent with those observed with this regimen. The maximal tolerated dose was 100 mg given every 2 weeks. The response rate was 45 %; median progression-free survival was 10.4 months, whereas 54.6 months of median overall survival was achieved. The optimized docetaxel plus epirubicin dosing regimen led to fewer toxicities associated with higher efficacy as compared with standard or empirical densified dosing. This study suggests that <span class="hlt">model</span>-driven dosage adjustment can lead to improved efficacy-toxicity balance in patients with cancer when several anticancer drugs are combined. PMID:27002506</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011E%26PSL.308..417T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011E%26PSL.308..417T"><span id="translatedtitle"><span class="hlt">Revisiting</span> HCN formation in Earth's early atmosphere</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tian, Feng; Kasting, J. F.; Zahnle, K.</p> <p>2011-08-01</p> <p>Using a new photochemical <span class="hlt">model</span>, the HCN chemistry in Earth's early atmosphere is <span class="hlt">revisited</span>. We find that HCN production in a CH 4-rich early atmosphere could have been efficient, similar to the results of a previous study (Zahnle, 1986). For an assumed CH 4 mixing ratio of 1000 ppmv, HCN surface deposition increases from 2 10 9 cm -2 s -1 at fCO 2 = 3% to more than 1 10 10 cm -2 s -1 (30 Tg/yr) at fCO 2 = 0.3% and 1%. These conditions may well have applied throughout much of the Archean eon, 3.8-2.5 Ga. Prior to the origin of life and the advent of methanogens, HCN production rates would likely have been at 1 10 7 cm -2 s -1 or lower, thereby providing a modest source of HCN for prebiotic synthesis.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_17 --> <div id="page_18" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="341"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26188384','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26188384"><span id="translatedtitle"><span class="hlt">Re-visiting</span> the electrophysiology of language.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Obleser, Jonas</p> <p>2015-09-01</p> <p>This editorial accompanies a special issue of Brain and Language <span class="hlt">re-visiting</span> old themes and new leads in the electrophysiology of language. The event-related potential (ERP) as a series of characteristic deflections ("components") over time and their distribution on the scalp has been exploited by speech and language researchers over decades to find support for diverse psycholinguistic <span class="hlt">models</span>. Fortunately, methodological and statistical advances have allowed human neuroscience to move beyond some of the limitations imposed when looking at the ERP only. Most importantly, we currently witness a refined and refreshed look at "event-related" (in the literal sense) brain activity that relates itself more closely to the actual neurobiology of speech and language processes. It is this imminent change in handling and interpreting electrophysiological data of speech and language experiments that this special issue intends to capture. PMID:26188384</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015NuPhB.900..533H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015NuPhB.900..533H"><span id="translatedtitle">Interpolating function and Stokes phenomena</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Honda, Masazumi; Jatkar, Dileep P.</p> <p>2015-11-01</p> <p>When we have two expansions of physical quantity around two different points in parameter space, we can usually construct a family of functions, which interpolates the both expansions. In this paper we study analytic structures of such interpolating functions and discuss their physical implications. We propose that the analytic structures of the interpolating functions provide information on analytic property and Stokes phenomena of the physical quantity, which we approximate by the interpolating functions. We explicitly check our proposal for partition functions of zero-dimensional ?4 theory and <span class="hlt">Sine-Gordon</span> <span class="hlt">model</span>. In the zero dimensional <span class="hlt">Sine-Gordon</span> <span class="hlt">model</span>, we compare our result with a recent result from resurgence analysis. We also comment on construction of interpolating function in Borel plane.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011JHEP...11..067S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011JHEP...11..067S"><span id="translatedtitle">Integrability vs supersymmetry: Poisson structures of the pohlmeyer reduction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schmidtt, David M.</p> <p>2011-11-01</p> <p>We construct recursively an infinite number of Poisson structures for the su- persymmetric integrable hierarchy governing the Pohlmeyer reduction of superstring sigma <span class="hlt">models</span> on the target spaces AdS n S n , n = 2,3,5. These Poisson structures are all non-local and not relativistic except one, which is the canonical Poisson structure of the semi-symmetric space <span class="hlt">sine-Gordon</span> <span class="hlt">model</span> (SSSSG). We verify that the superposition of the first three Poisson structures corresponds to the canonical Poisson structure of the reduced sigma <span class="hlt">model</span>. Using the recursion relations we construct commuting charges on the reduced sigma <span class="hlt">model</span> out of those of the SSSSG <span class="hlt">model</span> and in the process we explain the integrable origin of the Zukhovsky map and the twisted inner product used in the sigma <span class="hlt">model</span> side. Then, we compute the complete Poisson superalgebra for the conserved Drinfeld-Sokolov supercharges associated to an exotic kind of extended non-local rigid 2d supersymmetry recently introduced in the SSSSG context. The superalgebra has a kink central charge which turns out to be a generalization to the SSSSG <span class="hlt">models</span> of the well-known central extensions of the N = 1 <span class="hlt">sine-Gordon</span> and N = 2 complex <span class="hlt">sine-Gordon</span> <span class="hlt">model</span> Poisson superalgebras computed from 2d superspace. The computation is done in two different ways concluding the proof of the existence of 2d supersymmetry in the reduced sigma <span class="hlt">model</span> phase space under the boost invariant SSSSG Poisson structure.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/7599328','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/7599328"><span id="translatedtitle">HIV and tuberculosis: noncompliance <span class="hlt">revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Anastasio, C J</p> <p>1995-01-01</p> <p><span class="hlt">Revisiting</span> the stereotype of the noncompliant patient can transcend the frustrating or resentful feelings nurses may experience when caring for patients with HIV and tuberculosis. This reevaluation also can lend itself to developing mutually participative nurse-patient relationships. The author suggests relationship goals, assessment parameters, and intervention strategies--including a directly observed therapy (DOT) contract. These actions support a commitment to empowering both the nurse and the patient in their relationship in the TB treatment process. PMID:7599328</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=permissive+AND+parenting&pg=7&id=EJ544146','ERIC'); return false;" href="http://eric.ed.gov/?q=permissive+AND+parenting&pg=7&id=EJ544146"><span id="translatedtitle">The Discipline Controversy <span class="hlt">Revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Baumrind, Diana</p> <p>1996-01-01</p> <p>Found that neither the authoritative <span class="hlt">model</span> nor the liberal (permissive) <span class="hlt">model</span> offers parents an efficacious <span class="hlt">model</span> of childrearing. Each polarized <span class="hlt">model</span> contains an element of truth, but each demonizes the other. Argues that within a responsive and supportive parent-child relationship, prudent use of punishment is a necessary tool in discipline.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1035083','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1035083"><span id="translatedtitle">Pair Production Constraints on Superluminal Neutrinos <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Brodsky, Stanley J.; Gardner, Susan; /Kentucky U.</p> <p>2012-02-16</p> <p>We <span class="hlt">revisit</span> the pair creation constraint on superluminal neutrinos considered by Cohen and Glashow in order to clarify which types of superluminal <span class="hlt">models</span> are constrained. We show that a <span class="hlt">model</span> in which the superluminal neutrino is effectively light-like can evade the Cohen-Glashow constraint. In summary, any <span class="hlt">model</span> for which the CG pair production process operates is excluded because such timelike neutrinos would not be detected by OPERA or other experiments. However, a superluminal neutrino which is effectively lightlike with fixed p{sup 2} can evade the Cohen-Glashow constraint because of energy-momentum conservation. The coincidence involved in explaining the SN1987A constraint certainly makes such a picture improbable - but it is still intrinsically possible. The lightlike <span class="hlt">model</span> is appealing in that it does not violate Lorentz symmetry in particle interactions, although one would expect Hughes-Drever tests to turn up a violation eventually. Other evasions of the CG constraints are also possible; perhaps, e.g., the neutrino takes a 'short cut' through extra dimensions or suffers anomalous acceleration in matter. Irrespective of the OPERA result, Lorentz-violating interactions remain possible, and ongoing experimental investigation of such possibilities should continue.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1993PhRvB..48.3295L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1993PhRvB..48.3295L"><span id="translatedtitle">Spatially resolved study of the dynamics of Josephson tunnel junctions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lachenmann, S. G.; Doderer, T.; Huebener, R. P.; Quenter, D.; Niemeyer, J.; Ppel, R.</p> <p>1993-08-01</p> <p>By scanning superconducting Nb/Al2O3/Nb tunnel junctions of various geometries with an electron beam at low temperatures we have obtained spatially resolved two-dimensional images related with the dynamics of the junctions. In a current-biased junction the local thermal perturbation effected by the beam results in a voltage change ?V representing a convenient imaging-response signal. The spatial resolution is limited by a characteristic thermal healing length with a value of about 2 ?m in our experiments. We analyze our results in terms of the <span class="hlt">sine-Gordon</span> equation. For the interpretation of the spatially resolved voltage signal ?V we extend the energetic analysis of the perturbed <span class="hlt">sine-Gordon</span> system of McLaughlin and Scott by including the beam-induced local thermal perturbation. Our <span class="hlt">model</span> allows the quantitative comparison of our experimental two-dimensional images with the local dynamics expected from the perturbed <span class="hlt">sine-Gordon</span> equation. Our experiments include the observation of single-mode and multiple-mode cavity resonances, soliton oscillations, and flux-flow behavior.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=social+AND+support+AND+system&pg=7&id=EJ609780','ERIC'); return false;" href="http://eric.ed.gov/?q=social+AND+support+AND+system&pg=7&id=EJ609780"><span id="translatedtitle"><span class="hlt">Revisiting</span> "Rethinking Early Intervention".</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Dunst, Carl J.</p> <p>2000-01-01</p> <p>Major components of the social support and social systems approach to early intervention are reviewed, reflections are presented, and the future use of the <span class="hlt">model</span> are discussed. The paper concludes with an overview of a "third generation" <span class="hlt">model</span> integrating new evidence for studying and practicing family systems intervention. (Contains extensive…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/935310','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/935310"><span id="translatedtitle">SLIM--An Early Work <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Chao, Alex; /SLAC</p> <p>2008-07-25</p> <p>An early, but at the time illuminating, piece of work on how to deal with a general, linearly coupled accelerator lattice is <span class="hlt">revisited</span>. This work is based on the SLIM formalism developed in 1979-1981.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/16529776','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/16529776"><span id="translatedtitle">Rabbits killing birds <span class="hlt">revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhang, Jimin; Fan, Meng; Kuang, Yang</p> <p>2006-09-01</p> <p>We formulate and study a three-species population <span class="hlt">model</span> consisting of an endemic prey (bird), an alien prey (rabbit) and an alien predator (cat). Our <span class="hlt">model</span> overcomes several <span class="hlt">model</span> construction problems in existing <span class="hlt">models</span>. Moreover, our <span class="hlt">model</span> generates richer, more reasonable and realistic dynamics. We explore the possible control strategies to save or restore the bird by controlling or eliminating the rabbit or the cat when the bird is endangered. We confirm the existence of the hyperpredation phenomenon, which is a big potential threat to most endemic prey. Specifically, we show that, in an endemic prey-alien prey-alien predator system, eradication of introduced predators such as the cat alone is not always the best solution to protect endemic insular prey since predator control may fail to protect the indigenous prey when the control of the introduced prey is not carried out simultaneously. PMID:16529776</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25752537','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25752537"><span id="translatedtitle">Natural dispersion <span class="hlt">revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Johansen, istein; Reed, Mark; Bodsberg, Nils Rune</p> <p>2015-04-15</p> <p>This paper presents a new semi-empirical <span class="hlt">model</span> for oil droplet size distributions generated by single breaking wave events. Empirical data was obtained from laboratory experiments with different crude oils at different stages of weathering. The paper starts with a review of the most commonly used <span class="hlt">model</span> for natural dispersion, which is followed by a presentation of the laboratory study on oil droplet size distributions formed by breaking waves conducted by SINTEF on behalf of the NOAA/UNH Coastal Response Research Center. The next section presents the theoretical and empirical foundation for the new <span class="hlt">model</span>. The <span class="hlt">model</span> is based on dimensional analysis and contains two non-dimensional groups; the Weber and Reynolds number. The <span class="hlt">model</span> was validated with data from a full scale experimental oil spill conducted in the Haltenbanken area offshore Norway in July 1982, as described in the last section of the paper. PMID:25752537</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013APS..SHK.B6001V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013APS..SHK.B6001V"><span id="translatedtitle">The Sakharov Experiment <span class="hlt">Revisited</span> for Granular Materials</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vogler, Tracy</p> <p>2013-06-01</p> <p>Sakharov and co-workers in 1965 proposed an experiment in which a sinusoidal perturbation in a planar wave evolves as it travels through a material. More recent, Liu and co-workers utilized gas gun techniques rather than explosives to drive the shock wave, resulting in a better defined input. The technique has been applied to liquids such as water and mercury as well as solids such as aluminum. All analyses of the experiments conducted to date have utilized a viscous fluid approach, even for the solids. Here, the concept of the decay of a perturbation in a shock wave is <span class="hlt">revisited</span> and applied to granular materials. Simulations utilizing continuum <span class="hlt">models</span> for the granular materials as well as mesoscale <span class="hlt">models</span> in which individual particles are resolved are utilized. It is found that the perturbation decay is influenced by the strength (deviatoric behavior) used in the continuum <span class="hlt">model</span>. In the mesocale calculations, the simulation parameters as well as the computational approach influence the results. Finally, initial experimental results for the technique using granular tungsten carbide are presented. Sandia National Laboratories is a multi-program laboratory operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin company, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013PhLA..377.1555B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013PhLA..377.1555B"><span id="translatedtitle">Torsion pendulum <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bassan, Massimo; De Marchi, Fabrizio; Marconi, Lorenzo; Pucacco, Giuseppe; Stanga, Ruggero; Visco, Massimo</p> <p>2013-10-01</p> <p>We present an analysis of the motion of a simple torsion pendulum and we describe how, with straightforward extensions to the usual basic dynamical <span class="hlt">model</span>, we succeed in explaining some unexpected features we found in our data, like the modulation of the torsion mode at a higher frequency and the frequency splitting of the swinging motion. Comparison with observed values yields estimates for the misalignment angles and other parameters of the <span class="hlt">model</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=18&id=EJ1004745','ERIC'); return false;" href="http://eric.ed.gov/?q=18&id=EJ1004745"><span id="translatedtitle">Sunday School <span class="hlt">Revisited</span>: An Alternative to Christian Education of the Church Today?</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Song, Nam Soon</p> <p>2013-01-01</p> <p>This article attempts to demonstrate similarities between the socioeconomic, cultural, and religious contexts of 18th-century England and 21st-century Canada. <span class="hlt">Revisiting</span> the Sunday School movement in 18th-century England provides insights for the development of renewed Sunday School <span class="hlt">models</span> in the current Canadian context of transnational</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20010044996&hterms=love&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dlove','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20010044996&hterms=love&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dlove"><span id="translatedtitle">Atmospheric Entry Heating of Micrometeorites <span class="hlt">Revisited</span>: Higher Temperatures and Potential Biases</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Love, S.; Alexander, C. M. OD.</p> <p>2001-01-01</p> <p>The atmospheric entry heating <span class="hlt">model</span> of Love and Brownlee appears to have overestimated evaporation rates by as much as two orders of magnitude. Here we <span class="hlt">revisit</span> the issue of atmospheric entry heating, using a revised prescription for evaporation rates. Additional information is contained in the original extended abstract.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Immigration&pg=4&id=EJ1004745','ERIC'); return false;" href="http://eric.ed.gov/?q=Immigration&pg=4&id=EJ1004745"><span id="translatedtitle">Sunday School <span class="hlt">Revisited</span>: An Alternative to Christian Education of the Church Today?</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Song, Nam Soon</p> <p>2013-01-01</p> <p>This article attempts to demonstrate similarities between the socioeconomic, cultural, and religious contexts of 18th-century England and 21st-century Canada. <span class="hlt">Revisiting</span> the Sunday School movement in 18th-century England provides insights for the development of renewed Sunday School <span class="hlt">models</span> in the current Canadian context of transnational…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/821220','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/821220"><span id="translatedtitle">Melt fracture <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Greenberg, J. M.</p> <p>2003-07-16</p> <p>In a previous paper the author and Demay advanced a <span class="hlt">model</span> to explain the melt fracture instability observed when molten linear polymer melts are extruded in a capillary rheometer operating under the controlled condition that the inlet flow rate was held constant. The <span class="hlt">model</span> postulated that the melts were a slightly compressible viscous fluid and allowed for slipping of the melt at the wall. The novel feature of that <span class="hlt">model</span> was the use of an empirical switch law which governed the amount of wall slip. The <span class="hlt">model</span> successfully accounted for the oscillatory behavior of the exit flow rate, typically referred to as the melt fracture instability, but did not simultaneously yield the fine scale spatial oscillations in the melt typically referred to as shark skin. In this note a new <span class="hlt">model</span> is advanced which simultaneously explains the melt fracture instability and shark skin phenomena. The <span class="hlt">model</span> postulates that the polymer is a slightly compressible linearly viscous fluid but assumes no slip boundary conditions at the capillary wall. In simple shear the shear stress {tau}and strain rate d are assumed to be related by d = F{tau} where F ranges between F{sub 2} and F{sub 1} > F{sub 2}. A strain rate dependent yield function is introduced and this function governs whether F evolves towards F{sub 2} or F{sub 1}. This <span class="hlt">model</span> accounts for the empirical observation that at high shears polymers align and slide more easily than at low shears and explains both the melt fracture and shark skin phenomena.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4176655','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4176655"><span id="translatedtitle">Granger causality <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Friston, Karl J.; Bastos, Andr M.; Oswal, Ashwini; van Wijk, Bernadette; Richter, Craig; Litvak, Vladimir</p> <p>2014-01-01</p> <p>This technical paper offers a critical re-evaluation of (spectral) Granger causality measures in the analysis of biological timeseries. Using realistic (neural mass) <span class="hlt">models</span> of coupled neuronal dynamics, we evaluate the robustness of parametric and nonparametric Granger causality. Starting from a broad class of generative (state-space) <span class="hlt">models</span> of neuronal dynamics, we show how their Volterra kernels prescribe the second-order statistics of their response to random fluctuations; characterised in terms of cross-spectral density, cross-covariance, autoregressive coefficients and directed transfer functions. These quantities in turn specify Granger causality providing a direct (analytic) link between the parameters of a generative <span class="hlt">model</span> and the expected Granger causality. We use this link to show that Granger causality measures based upon autoregressive <span class="hlt">models</span> can become unreliable when the underlying dynamics is dominated by slow (unstable) modes as quantified by the principal Lyapunov exponent. However, nonparametric measures based on causal spectral factors are robust to dynamical instability. We then demonstrate how both parametric and nonparametric spectral causality measures can become unreliable in the presence of measurement noise. Finally, we show that this problem can be finessed by deriving spectral causality measures from Volterra kernels, estimated using dynamic causal <span class="hlt">modelling</span>. PMID:25003817</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25003817','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25003817"><span id="translatedtitle">Granger causality <span class="hlt">revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Friston, Karl J; Bastos, André M; Oswal, Ashwini; van Wijk, Bernadette; Richter, Craig; Litvak, Vladimir</p> <p>2014-11-01</p> <p>This technical paper offers a critical re-evaluation of (spectral) Granger causality measures in the analysis of biological timeseries. Using realistic (neural mass) <span class="hlt">models</span> of coupled neuronal dynamics, we evaluate the robustness of parametric and nonparametric Granger causality. Starting from a broad class of generative (state-space) <span class="hlt">models</span> of neuronal dynamics, we show how their Volterra kernels prescribe the second-order statistics of their response to random fluctuations; characterised in terms of cross-spectral density, cross-covariance, autoregressive coefficients and directed transfer functions. These quantities in turn specify Granger causality - providing a direct (analytic) link between the parameters of a generative <span class="hlt">model</span> and the expected Granger causality. We use this link to show that Granger causality measures based upon autoregressive <span class="hlt">models</span> can become unreliable when the underlying dynamics is dominated by slow (unstable) modes - as quantified by the principal Lyapunov exponent. However, nonparametric measures based on causal spectral factors are robust to dynamical instability. We then demonstrate how both parametric and nonparametric spectral causality measures can become unreliable in the presence of measurement noise. Finally, we show that this problem can be finessed by deriving spectral causality measures from Volterra kernels, estimated using dynamic causal <span class="hlt">modelling</span>. PMID:25003817</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26618655','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26618655"><span id="translatedtitle">Cleckley's psychopaths: <span class="hlt">Revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Crego, Cristina; Widiger, Thomas A</p> <p>2016-01-01</p> <p>The most influential figure in the study of psychopathy is Hervey Cleckley, the author of the widely cited text, "The Mask of Sanity" (Cleckley, 1941, 1955). Researchers often refer to Cleckley when disputing what should belong within a conceptualization or assessment of psychopathy, at times disagreeing as to what Cleckley meant or intended. Cleckley though included within his text 15 detailed case studies of prototypic psychopaths. The current study was the first to provide systematic ratings of these 15 cases, including ratings with respect to (a) the 16 Cleckley criteria (e.g., anxiousness and inadequately motivated antisocial behavior), (b) 33 additional traits included within or considered for more recently developed measures and <span class="hlt">models</span> of psychopathy (e.g., boldness, fearlessness, disobliged, cruelty, and aggression), and (c) 30 traits of the 5-factor <span class="hlt">model</span> of general personality. The results are discussed with respect to implications for both historic and current <span class="hlt">models</span> of psychopathy. (PsycINFO Database Record PMID:26618655</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_18 --> <div id="page_19" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="361"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JCAP...03..008E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JCAP...03..008E"><span id="translatedtitle">Post-inflationary gravitino production <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ellis, John; Garcia, Marcos A. G.; Nanopoulos, Dimitri V.; Olive, Keith A.; Peloso, Marco</p> <p>2016-03-01</p> <p>We <span class="hlt">revisit</span> gravitino production following inflation. As a first step, we review the standard calculation of gravitino production in the thermal plasma formed at the end of post-inflationary reheating when the inflaton has completely decayed. Next we consider gravitino production prior to the completion of reheating, assuming that the inflaton decay products thermalize instantaneously while they are still dilute. We then argue that instantaneous thermalization is in general a good approximation, and also show that the contribution of non-thermal gravitino production via the collisions of inflaton decay products prior to thermalization is relatively small. Our final estimate of the gravitino-to-entropy ratio is approximated well by a standard calculation of gravitino production in the post-inflationary thermal plasma assuming total instantaneous decay and thermalization at a time t simeq 1.2/Γphi. Finally, in light of our calculations, we consider potential implications of upper limits on the gravitino abundance for <span class="hlt">models</span> of inflation, with particular attention to scenarios for inflaton decays in supersymmetric Starobinsky-like <span class="hlt">models</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=corporate+AND+governance&pg=4&id=EJ624688','ERIC'); return false;" href="http://eric.ed.gov/?q=corporate+AND+governance&pg=4&id=EJ624688"><span id="translatedtitle">Policy Governance <span class="hlt">Revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Price, William J.</p> <p>2001-01-01</p> <p>An administrator trainer/former superintendent's experience suggests that corporate governance <span class="hlt">models</span> don't fit the reality of school governance in many districts. Elected board members define their roles differently than their business counterparts and derive little or no monetary benefit from public service. The "new breed" resemble political</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22373453','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22373453"><span id="translatedtitle">Emergent cosmology <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Bag, Satadru; Sahni, Varun; Shtanov, Yuri; Unnikrishnan, Sanil E-mail: varun@iucaa.ernet.in E-mail: sanil@lnmiit.ac.in</p> <p>2014-07-01</p> <p>We explore the possibility of emergent cosmology using the effective potential formalism. We discover new <span class="hlt">models</span> of emergent cosmology which satisfy the constraints posed by the cosmic microwave background (CMB). We demonstrate that, within the framework of modified gravity, the emergent scenario can arise in a universe which is spatially open/closed. By contrast, in general relativity (GR) emergent cosmology arises from a spatially closed past-eternal Einstein Static Universe (ESU). In GR the ESU is unstable, which creates fine tuning problems for emergent cosmology. However, modified gravity <span class="hlt">models</span> including Braneworld <span class="hlt">models</span>, Loop Quantum Cosmology (LQC) and Asymptotically Free Gravity result in a stable ESU. Consequently, in these <span class="hlt">models</span> emergent cosmology arises from a larger class of initial conditions including those in which the universe eternally oscillates about the ESU fixed point. We demonstrate that such an oscillating universe is necessarily accompanied by graviton production. For a large region in parameter space graviton production is enhanced through a parametric resonance, casting serious doubts as to whether this emergent scenario can be past-eternal.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19730005656','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19730005656"><span id="translatedtitle">The air afterglow <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kaufman, F.</p> <p>1972-01-01</p> <p>The air afterglow, 0 + NO2 chemiluminescence, is discussed in terms of fluorescence, photodissociation, and quantum theoretical calculations of NO2. The experimental results presented include pressure dependence, M-dependence, spectral dependence of P and M, temperature dependence, and infrared measurements. The NO2 energy transfer <span class="hlt">model</span> is also discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25953388','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25953388"><span id="translatedtitle">Games among relatives <span class="hlt">revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Allen, Benjamin; Nowak, Martin A</p> <p>2015-08-01</p> <p>We present a simple <span class="hlt">model</span> for the evolution of social behavior in family-structured, finite sized populations. Interactions are represented as evolutionary games describing frequency-dependent selection. Individuals interact more frequently with siblings than with members of the general population, as quantified by an assortment parameter r, which can be interpreted as "relatedness". Other <span class="hlt">models</span>, mostly of spatially structured populations, have shown that assortment can promote the evolution of cooperation by facilitating interaction between cooperators, but this effect depends on the details of the evolutionary process. For our <span class="hlt">model</span>, we find that sibling assortment promotes cooperation in stringent social dilemmas such as the Prisoner's Dilemma, but not necessarily in other situations. These results are obtained through straightforward calculations of changes in gene frequency. We also analyze our <span class="hlt">model</span> using inclusive fitness. We find that the quantity of inclusive fitness does not exist for general games. For special games, where inclusive fitness exists, it provides less information than the straightforward analysis. PMID:25953388</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=monetary+AND+policy+AND+definition&id=EJ624688','ERIC'); return false;" href="http://eric.ed.gov/?q=monetary+AND+policy+AND+definition&id=EJ624688"><span id="translatedtitle">Policy Governance <span class="hlt">Revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Price, William J.</p> <p>2001-01-01</p> <p>An administrator trainer/former superintendent's experience suggests that corporate governance <span class="hlt">models</span> don't fit the reality of school governance in many districts. Elected board members define their roles differently than their business counterparts and derive little or no monetary benefit from public service. The "new breed" resemble political…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/6845771','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/6845771"><span id="translatedtitle">The quench front <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Wendroff, B.</p> <p>1988-01-01</p> <p>The cooling of hot surfaces can be <span class="hlt">modeled</span> in certain simples cases by a nonlinear eigenvalue problem describing the motion of a steady traveling cooling wave. Earlier work on the mathematical theory, the numerical analysis, and the asymptotics of this problem are reviewed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/EJ1083712.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/EJ1083712.pdf"><span id="translatedtitle"><span class="hlt">Revisiting</span> "Beyond Instructional Design"</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Sims, Rod</p> <p>2015-01-01</p> <p>Since the article "Beyond Instructional Design: Making Learning Design a Reality" (Sims, 2006) was published, much has changed in the opportunities we have for learning, and Professor Rod Sims's thinking has evolved. In this article, Professor Rod Sims reflects upon his original article, and he offers an evolved <span class="hlt">model</span> of learning design,…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JCAP...12..011M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JCAP...12..011M"><span id="translatedtitle">Dark matter relic density in scalar-tensor gravity <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Meehan, Michael T.; Whittingham, Ian B.</p> <p>2015-12-01</p> <p>We <span class="hlt">revisit</span> the calculation of dark matter relic abundances in scalar-tensor gravity using a generic form A(varphi*) = eβvarphi*2/2 for the coupling between the scalar field varphi* and the metric, for which detailed Big Bang Nucleosynthesis constraints are available. We find that BBN constraints restrict the modified expansion rate in these <span class="hlt">models</span> to be almost degenerate with the standard expansion history at the time of dark matter decoupling. In this case the maximum level of enhancement of the dark matter relic density was found to be a factor of ~ 3, several orders of magnitude below that found in previous investigations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014cosp...40E2101M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014cosp...40E2101M"><span id="translatedtitle"><span class="hlt">Revisiting</span> and updating the Mars International Reference Atmosphere MIRA</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Millour, Ehouarn; Forget, Francois; Montabone, Luca</p> <p></p> <p>Since the elaboration of the COSPAR Mars International Reference Atmosphere (MIRA) in 1982, our knowledge of the Martian atmosphere and its main (CO2, dust, water) cycles has been greatly improved. This is firstly due to the recent continuous multi-annual observations gathered by instruments on board the Mars Global Surveyor, Mars Odyssey, Mars Express and Mars Reconnaissance Orbiter spacecrafts. The development of <span class="hlt">models</span> capable of matching these observations have also contributed to better understand the physical processes at work on Mars. At the COSPAR 2014 scientific assembly, we will address <span class="hlt">revisiting</span> MIRA and assess on possible ways of updating it to match our current knowledge of the Martian atmosphere.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2492820','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2492820"><span id="translatedtitle">Allostery and cooperativity <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Cui, Qiang; Karplus, Martin</p> <p>2008-01-01</p> <p>Although phenomenlogical <span class="hlt">models</span> that account for cooperativity in allosteric systems date back to the early and mid-60's (e.g., the KNF and MWC <span class="hlt">models</span>), there is resurgent interest in the topic due to the recent experimental and computational studies that attempted to reveal, at an atomistic level, how allostery actually works. In this review, using systems for which atomistic simulations have been carried out in our groups as examples, we describe the current understanding of allostery, how the mechanisms go beyond the classical MWC/Pauling-KNF descriptions, and point out that the new view of allostery, emphasizing population shifts, is, in fact, an old view. The presentation offers not only an up-to-date description of allostery from a theoretical/computational perspective, but also helps to resolve several outstanding issues concerning allostery. PMID:18560010</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=wilson&pg=2&id=EJ1084290','ERIC'); return false;" href="http://eric.ed.gov/?q=wilson&pg=2&id=EJ1084290"><span id="translatedtitle"><span class="hlt">Revisiting</span> Classroom Routines</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Wilson, Gloria Lodato</p> <p>2016-01-01</p> <p>Most co-teachers agree that there just isn't enough time for co-teachers to appropriately and effectively preplan every aspect of every activity in every lesson. This lack of time leads co-teachers to turn to <span class="hlt">models</span> that fail to maximize the benefits of a two-teacher classroom. Wilson suggests that if co-teachers use their limited planning time to…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015Ap%26SS.357...47C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015Ap%26SS.357...47C"><span id="translatedtitle">Twisted Crab fingers <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Carlqvist, Per</p> <p>2015-05-01</p> <p>Narrowband images of the Crab Nebula captured by the Hubble Space Telescope have earlier shown that the nebula does not only present a network of broad, bright filaments crossing the nebula but also numerous so-called fingers mostly pointing inwards. Using archival Hubble images we have in some detail studied the morphology of a great number of such fingers. This scrutiny has revealed that practically all the fingers are made up of filaments. Most of the larger fingers show overall shapes that are similar to either of the two letters V and Y. In many of these fingers it is also possible to see internal details. Interestingly, a number of the larger, Y-shaped fingers turn out to have a stem that consists of intertwined filaments. By contrast with this, the smaller fingers usually appear only as diffuse and sometimes incomplete pegs. In none of the smaller fingers is it possible to find any plain, internal structure. The observational results obtained are compared with the properties of a previously proposed <span class="hlt">model</span> of the fingers. The <span class="hlt">model</span> suggests that the fingers have evolved out of magnetized filaments. The evolution should lead to fingers with overall shapes that are similar to either a V or a Y, very much in agreement with the observations. In addition to this, the <span class="hlt">model</span> prescribes that the stems of the Y-shaped fingers should be made up of intertwined filaments. From all these points of agreement we conclude that the properties of the fingers observed lend strong support to the <span class="hlt">model</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22266005','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22266005"><span id="translatedtitle">Geometrical deuteron stripping <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Neoh, Y. S.; Yap, S. L.</p> <p>2014-03-05</p> <p>We investigate the reality of the idea of geometrical deuteron stripping originally envisioned by Serber. By taking into account of realistic deuteron wavefunction, nuclear density, and nucleon stopping mean free path, we are able to estimate inclusive deuteron stripping cross section for deuteron energy up to before pion production. Our semiclassical <span class="hlt">model</span> contains only one global parameter constant for all nuclei which can be approximated by Woods-Saxon or any other spherically symmetric density distribution.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25780063','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25780063"><span id="translatedtitle">Cube search, <span class="hlt">revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhang, Xuetao; Huang, Jie; Yigit-Elliott, Serap; Rosenholtz, Ruth</p> <p>2015-01-01</p> <p>Observers can quickly search among shaded cubes for one lit from a unique direction. However, replace the cubes with similar 2-D patterns that do not appear to have a 3-D shape, and search difficulty increases. These results have challenged <span class="hlt">models</span> of visual search and attention. We demonstrate that cube search displays differ from those with "equivalent" 2-D search items in terms of the informativeness of fairly low-level image statistics. This informativeness predicts peripheral discriminability of target-present from target-absent patches, which in turn predicts visual search performance, across a wide range of conditions. Comparing <span class="hlt">model</span> performance on a number of classic search tasks, cube search does not appear unexpectedly easy. Easy cube search, per se, does not provide evidence for preattentive computation of 3-D scene properties. However, search asymmetries derived from rotating and/or flipping the cube search displays cannot be explained by the information in our current set of image statistics. This may merely suggest a need to modify the <span class="hlt">model</span>'s set of 2-D image statistics. Alternatively, it may be difficult cube search that provides evidence for preattentive computation of 3-D scene properties. By attributing 2-D luminance variations to a shaded 3-D shape, 3-D scene understanding may slow search for 2-D features of the target. PMID:25780063</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.9930G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.9930G"><span id="translatedtitle"><span class="hlt">Revisiting</span> Antarctic Ozone Depletion</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Groo, Jens-Uwe; Tritscher, Ines; Mller, Rolf</p> <p>2015-04-01</p> <p>Antarctic ozone depletion is known for almost three decades and it has been well settled that it is caused by chlorine catalysed ozone depletion inside the polar vortex. However, there are still some details, which need to be clarified. In particular, there is a current debate on the relative importance of liquid aerosol and crystalline NAT and ice particles for chlorine activation. Particles have a threefold impact on polar chlorine chemistry, temporary removal of HNO3 from the gas-phase (uptake), permanent removal of HNO3 from the atmosphere (denitrification), and chlorine activation through heterogeneous reactions. We have performed simulations with the Chemical Lagrangian <span class="hlt">Model</span> of the Stratosphere (CLaMS) employing a recently developed algorithm for saturation-dependent NAT nucleation for the Antarctic winters 2011 and 2012. The simulation results are compared with different satellite observations. With the help of these simulations, we investigate the role of the different processes responsible for chlorine activation and ozone depletion. Especially the sensitivity with respect to the particle type has been investigated. If temperatures are artificially forced to only allow cold binary liquid aerosol, the simulation still shows significant chlorine activation and ozone depletion. The results of the 3-D Chemical Transport <span class="hlt">Model</span> CLaMS simulations differ from purely Lagrangian longtime trajectory box <span class="hlt">model</span> simulations which indicates the importance of mixing processes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25161638','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25161638"><span id="translatedtitle"><span class="hlt">Revisiting</span> Tversky's diagnosticity principle.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Evers, Ellen R K; Lakens, Danil</p> <p>2014-01-01</p> <p>Similarity is a fundamental concept in cognition. In 1977, Amos Tversky published a highly influential feature-based <span class="hlt">model</span> of how people judge the similarity between objects. The <span class="hlt">model</span> highlights the context-dependence of similarity judgments, and challenged geometric <span class="hlt">models</span> of similarity. One of the context-dependent effects Tversky describes is the diagnosticity principle. The diagnosticity principle determines which features are used to cluster multiple objects into subgroups. Perceived similarity between items within clusters is expected to increase, while similarity between items in different clusters decreases. Here, we present two pre-registered replications of the studies on the diagnosticity effect reported in Tversky (1977). Additionally, one alternative mechanism that has been proposed to play a role in the original studies, an increase in the choice for distractor items (a substitution effect, see Medin et al., 1995), is examined. Our results replicate those found by Tversky (1977), revealing an average diagnosticity-effect of 4.75%. However, when we eliminate the possibility of substitution effects confounding the results, a meta-analysis of the data provides no indication of any remaining effect of diagnosticity. PMID:25161638</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4130183','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4130183"><span id="translatedtitle"><span class="hlt">Revisiting</span> Tversky's diagnosticity principle</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Evers, Ellen R. K.; Lakens, Danil</p> <p>2013-01-01</p> <p>Similarity is a fundamental concept in cognition. In 1977, Amos Tversky published a highly influential feature-based <span class="hlt">model</span> of how people judge the similarity between objects. The <span class="hlt">model</span> highlights the context-dependence of similarity judgments, and challenged geometric <span class="hlt">models</span> of similarity. One of the context-dependent effects Tversky describes is the diagnosticity principle. The diagnosticity principle determines which features are used to cluster multiple objects into subgroups. Perceived similarity between items within clusters is expected to increase, while similarity between items in different clusters decreases. Here, we present two pre-registered replications of the studies on the diagnosticity effect reported in Tversky (1977). Additionally, one alternative mechanism that has been proposed to play a role in the original studies, an increase in the choice for distractor items (a substitution effect, see Medin et al., 1995), is examined. Our results replicate those found by Tversky (1977), revealing an average diagnosticity-effect of 4.75%. However, when we eliminate the possibility of substitution effects confounding the results, a meta-analysis of the data provides no indication of any remaining effect of diagnosticity. PMID:25161638</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19870009041','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19870009041"><span id="translatedtitle">MR Cygni <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Linnell, Albert P.; Kallrath, Josef</p> <p>1986-01-01</p> <p>New analysis tools and additional unanalyzed observations justify a reanalysis of MR Cygni. The reanalysis applied successively more restrictive physical <span class="hlt">models</span>, each with an optimization program. The final <span class="hlt">model</span> assigned separate first and second order limb darkening coefficients, from <span class="hlt">model</span> atmospheres, to individual grid points. Proper operation of the optimization procedure was tested on simulated observational data, produced by light synthesis with assigned system parameters, and modulated by simulated observational error. The iterative solution converged to a weakly-determined mass ratio of 0.75. Assuming the B3 primary component is on the main sequence, the HR diagram location of the secondary from the light ratio (ordinate) and adjusted T sub eff (abscissa) was calculated. The derived mass ratio, together with a main-sequence mass for the B3 component, implies a main-sequence secondary spectral type of B4. The photometrically-determined secondary radii agree with this spectral type, in marginal disagreement with the B7 type from the HR diagram analysis. The individual masses, derived from the radial velocity curve of the primary component, the photometrically-determined i, and alternative values of derived mass ratio are seriously discrepant with main sequence objects. The imputed physical status of the system is in disagreement with representations that have appeared in the literature.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006AGUFM.H54E..04K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006AGUFM.H54E..04K"><span id="translatedtitle">The Henry Problem <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Karasaki, K.; Oldenburg, C. M.; Maekawa, K.</p> <p>2006-12-01</p> <p>We have <span class="hlt">modeled</span> laboratory experiments of saltwater intrusion in a configuration resembling the so-called Henry Problem using TOUGH2/EOS7. The experiment differs from the Henry Problem in that the freshwater boundary condition is that of Dirichlet, a difference that is not expected to affect the overall results very much. The simulation matched the saltwater wedge profile of the experiment, the main feature of which was the sharp interface (lack of dispersion) between the freshwater and saltwater. Prior solutions of the Henry Problem show a wide transition zone between freshwater and saltwater arising from the use of a large dispersion coefficient. Henry attributed the large dispersion to the effect of tidally induced motion. In our simulation, we imposed a time-varying sinusoidal boundary condition to see if a larger transition zone can be created without using a larger dispersion coefficient. However, for the parameters used we were not able to do so. It is still plausible that the wide transition zone observed at Biscayne Bay (and as <span class="hlt">modeled</span> in the Henry Problem) is caused by a particular formation heterogeneity and transient effects. Our analysis, based on a laboratory experiment and accompanying <span class="hlt">modeling</span>, suggests that dispersion is quite limited. Nonetheless, we question the validity of the use of a large dispersion coefficient where the groundwater velocity is very low, or where the flow is in the opposite direction of the concentration gradient. This work was supported by the U.S. Department of Energy under Contract No. DE-AC02-05CH11231</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_19 --> <div id="page_20" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="381"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/560648','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/560648"><span id="translatedtitle">Inductive electron heating <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Tuszewski, M.</p> <p>1997-05-01</p> <p>The induced rf magnetic fields of low-frequency inductively coupled plasmas are measured and <span class="hlt">modeled</span> [M. Tuszewski, Phys. Rev. Lett. {bold 77}, 1286 (1996)]. The fields penetrate deep into the discharges, in contrast with existing predictions of field decay within a thin skin layer. Fluid calculations suggest that the enhanced rf penetration is due to a reduction of the plasma conductivity by the induced magnetic fields. In this paper, new oxygen and argon data concerning rf power absorption are reported and a general description of inductive electron heating is suggested. {copyright} {ital 1997 American Institute of Physics.}</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110013297','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110013297"><span id="translatedtitle">Radiolytic Cryovolcanism <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Cooper, John F.</p> <p>2011-01-01</p> <p>Location of Enceladus within the inner magnetosphere of Saturn makes it likely that energetic electron irradiation, ion-neutral chemistry of the emergent cryovolcanic plume gas, and resultant radiolytic modification of surface ice composition could impact long-term evolution of molecular composition in the global ice crust. Thermally-driven convection of ice in the south polar terrain would bring radiolytic oxidant products into contact with subsurface reservoirs of primordial organics on million-year time scales. The chemical reactions leading to CO2 gas production as a primary gas-piston driver of cryovolcanic activity would be exponentially elevated in the warm-ice margins of a heated fluid. The fluid temperature is typically assumed to be below 273 K but could be much higher in a gas-pressurized deep subsurface environment. The Perrier Ocean <span class="hlt">model</span> has demonstrated how a CO2-loaded fluid could account for the observed jets, while the heat content of the fluid arising from the moon's deeper interior could support high levels of chemical reactivity in the thermal margins. Since mass loss and tidal dissipation arguments do not support continuous activity over billions of years, the activity is likely very episodic so that even low-level energy sources including irradiation-driven radiolysis of surface ices could substantially contribute to the chemical dynamics of the activity apparently now in high phase. A multi-phase thermochemical <span class="hlt">model</span>, and supporting laboratory measurements of temperature-dependent reaction rates, are needed to investigate these potentially complex processes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009LNCS.5087..237L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009LNCS.5087..237L"><span id="translatedtitle">Secret Public Key Protocols <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lim, Hoon Wei; Paterson, Kenneth G.</p> <p></p> <p>Password-based protocols are important and popular means of providing human-to-machine authentication. The concept of secret public keys was proposed more than a decade ago as a means of securing password-based authentication protocols against off-line password guessing attacks, but was later found vulnerable to various attacks. In this paper, we <span class="hlt">revisit</span> the concept and introduce the notion of identity-based secret public keys. Our new identity-based approach allows secret public keys to be constructed in a very natural way using arbitrary random strings, eliminating the structure found in, for example, RSA or ElGamal keys. We examine identity-based secret public key protocols and give informal security analyses, indicating that they are secure against off-line password guessing and other attacks.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PEPI..235...66K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PEPI..235...66K"><span id="translatedtitle">Hotspot swells <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>King, Scott D.; Adam, Claudia</p> <p>2014-10-01</p> <p>The first attempts to quantify the width and height of hotspot swells were made more than 30 years ago. Since that time, topography, ocean-floor age, and sediment thickness datasets have improved considerably. Swell heights and widths have been used to estimate the heat flow from the core-mantle boundary, constrain numerical <span class="hlt">models</span> of plumes, and as an indicator of the origin of hotspots. In this paper, we repeat the analysis of swell geometry and buoyancy flux for 54 hotspots, including the 37 considered by Sleep (1990) and the 49 considered by Courtillot et al. (2003), using the latest and most accurate data. We are able to calculate swell geometry for a number of hotspots that Sleep was only able to estimate by comparison with other swells. We find that in spite of the increased resolution in global bathymetry <span class="hlt">models</span> there is significant uncertainty in our calculation of buoyancy fluxes due to differences in our measurement of the swells’ width and height, the integration method (volume integration or cross-sectional area), and the variations of the plate velocities between HS2-Nuvel1a (Gripp and Gordon, 1990) and HS3-Nuvel1a (Gripp and Gordon, 2002). We also note that the buoyancy flux for Pacific hotspots is in general larger than for Eurasian, North American, African and Antarctic hotspots. Considering that buoyancy flux is linearly related to plate velocity, we speculate that either the calculation of buoyancy flux using plate velocity over-estimates the actual vertical flow of material from the deep mantle or that convection in the Pacific hemisphere is more vigorous than the Atlantic hemisphere.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009ApJ...700..262S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009ApJ...700..262S"><span id="translatedtitle">Global Star Formation <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Silk, Joseph; Norman, Colin</p> <p>2009-07-01</p> <p>A general treatment of disk star formation is developed from a dissipative multiphase <span class="hlt">model</span>, with the dominant dissipation due to cloud collisions. The Schmidt-Kennicutt (SK) law emerges naturally for star-forming disks and starbursts. We predict that there should be an inverse correlation between Tully-Fisher law and SK law residuals. The <span class="hlt">model</span> is extended to include a multiphase treatment of supernova feedback that leads to a turbulent pressure-regulated generalization of the star formation law and is applicable to gas-rich starbursts. Enhanced pressure, as expected in merger-induced star formation, enhances star formation efficiency. An upper limit is derived for the disk star formation rate in starbursts that depends on the ratio of global ISM to cloud pressures. We extend these considerations to the case where the interstellar gas pressure in the inner galaxy is dominated by outflows from a central active galactic nucleus (AGN). During massive spheroid formation, AGN-driven winds trigger star formation, resulting in enhanced supernova feedback and outflows. The outflows are comparable to the AGN-boosted star formation rate and saturate in the super-Eddington limit. Downsizing of both SMBH and spheroids is a consequence of AGN-driven positive feedback. Bondi accretion feeds the central black hole with a specific accretion rate that is proportional to the black hole mass. AGN-enhanced star formation is mediated by turbulent pressure and relates spheroid star formation rate to black hole accretion rate. The relation between black hole mass and spheroid velocity dispersion has a coefficient (Salpeter time to gas consumption time ratio) that provides an arrow of time. Highly efficient, AGN-boosted star formation can occur at high redshift.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006JGRE..111.6S07S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006JGRE..111.6S07S"><span id="translatedtitle">Hagfors' law <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sultan-Salem, Ahmed K.; Tyler, G. Leonard</p> <p>2006-04-01</p> <p>Hagfors' scattering law, σ°H($\\theta$), is in wide use in connection with the study of backscatter data from planetary surfaces because it provides good agreement with a variety of observations. The surface root-mean-square slope inferred on the basis of σ°H($\\theta$) is customarily taken as C-1/2, where C is the shape parameter in σ°H($\\theta$). The relationship between the surface slope and C is indefinite, however, because of the indeterminateness of the surface scales contributing to the scattering process. Moreover, the horizontal scale of the inferred slope obtained is not specified. As a consequence of limitations in the Kirchhoff approximation on which it is predicated, σ°H($\\theta$) does not conserve energy. The use of a fractional Brownian fractal surface <span class="hlt">model</span> leads to a scattering law with the same functional form as σ°H($\\theta$) when the Hurst exponent characterizing the fractal <span class="hlt">model</span> is 1/2. Fractal-based scattering laws, derived by applying the Kirchhoff approximation, suffer the same deficiency with regard to conservation of energy. In contrast to σ°H($\\theta$), slope information for fractal-based laws is explicit with respect to horizontal scale. Both σ°H($\\theta$) and fractal-based laws require that the illuminated surface area exceeds a certain value, which is a function of the electromagnetic wavelength and surface parameters, in order to reduce the surface radar cross section overestimation error, introduced by a mathematical approximation, below some specified value. This requirement may be necessary to take into account in experiments where the radar resolution cells are comparable in size to the wavelength, such as in Mars Advanced Radar for Subsurface and Ionosphere Sounding (MARSIS).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21313894','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21313894"><span id="translatedtitle">GLOBAL STAR FORMATION <span class="hlt">REVISITED</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Silk, Joseph; Norman, Colin E-mail: norman@stsci.edu</p> <p>2009-07-20</p> <p>A general treatment of disk star formation is developed from a dissipative multiphase <span class="hlt">model</span>, with the dominant dissipation due to cloud collisions. The Schmidt-Kennicutt (SK) law emerges naturally for star-forming disks and starbursts. We predict that there should be an inverse correlation between Tully-Fisher law and SK law residuals. The <span class="hlt">model</span> is extended to include a multiphase treatment of supernova feedback that leads to a turbulent pressure-regulated generalization of the star formation law and is applicable to gas-rich starbursts. Enhanced pressure, as expected in merger-induced star formation, enhances star formation efficiency. An upper limit is derived for the disk star formation rate in starbursts that depends on the ratio of global ISM to cloud pressures. We extend these considerations to the case where the interstellar gas pressure in the inner galaxy is dominated by outflows from a central active galactic nucleus (AGN). During massive spheroid formation, AGN-driven winds trigger star formation, resulting in enhanced supernova feedback and outflows. The outflows are comparable to the AGN-boosted star formation rate and saturate in the super-Eddington limit. Downsizing of both SMBH and spheroids is a consequence of AGN-driven positive feedback. Bondi accretion feeds the central black hole with a specific accretion rate that is proportional to the black hole mass. AGN-enhanced star formation is mediated by turbulent pressure and relates spheroid star formation rate to black hole accretion rate. The relation between black hole mass and spheroid velocity dispersion has a coefficient (Salpeter time to gas consumption time ratio) that provides an arrow of time. Highly efficient, AGN-boosted star formation can occur at high redshift.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ACP....15.3803S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ACP....15.3803S"><span id="translatedtitle"><span class="hlt">Revisiting</span> Twomey's approximation for peak supersaturation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shipway, B. J.</p> <p>2015-04-01</p> <p>Twomey's seminal 1959 paper provided lower and upper bound approximations to the estimation of peak supersaturation within an updraft and thus provides the first closed expression for the number of nucleated cloud droplets. The form of this approximation is simple, but provides a surprisingly good estimate and has subsequently been employed in more sophisticated treatments of nucleation parametrization. In the current paper, we <span class="hlt">revisit</span> the lower bound approximation of Twomey and make a small adjustment that can be used to obtain a more accurate calculation of peak supersaturation under all potential aerosol loadings and thermodynamic conditions. In order to make full use of this improved approximation, the underlying integro-differential equation for supersaturation evolution and the condition for calculating peak supersaturation are examined. A simple rearrangement of the algebra allows for an expression to be written down that can then be solved with a single lookup table with only one independent variable for an underlying lognormal aerosol population. While multimodal aerosol with N different dispersion characteristics requires 2N+1 inputs to calculate the activation fraction, only N of these one-dimensional lookup tables are needed. No additional information is required in the lookup table to deal with additional chemical, physical or thermodynamic properties. The resulting implementation provides a relatively simple, yet computationally cheap, physically based parametrization of droplet nucleation for use in climate and Numerical Weather Prediction <span class="hlt">models</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007JMP....48j2302K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007JMP....48j2302K"><span id="translatedtitle">The Casimir effect for parallel plates <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kawakami, N. A.; Nemes, M. C.; Wreszinski, Walter F.</p> <p>2007-10-01</p> <p>The Casimir effect for a massless scalar field with Dirichlet and periodic boundary conditions (bc's) on infinite parallel plates is <span class="hlt">revisited</span> in the local quantum field theory (lqft) framework introduced by Kay [Phys. Rev. D 20, 3052 (1979)]. The <span class="hlt">model</span> displays a number of more realistic features than the ones he treated. In addition to local observables, as the energy density, we propose to consider intensive variables, such as the energy per unit area ?, as fundamental observables. Adopting this view, lqft rejects Dirichlet (the same result may be proved for Neumann or mixed) bc, and accepts periodic bc: in the former case ? diverges, in the latter it is finite, as is shown by an expression for the local energy density obtained from lqft through the use of the Poisson summation formula. Another way to see this uses methods from the Euler summation formula: in the proof of regularization independence of the energy per unit area, a regularization-dependent surface term arises upon use of Dirichlet bc, but not periodic bc. For the conformally invariant scalar quantum field, this surface term is absent due to the condition of zero trace of the energy momentum tensor, as remarked by De Witt [Phys. Rep. 19, 295 (1975)]. The latter property does not hold in the application to the dark energy problem in cosmology, in which we argue that periodic bc might play a distinguished role.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19760025662','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19760025662"><span id="translatedtitle">The plasmapause <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Maynard, N. C.; Gebowsky, J. M.</p> <p>1976-01-01</p> <p>Saturation of the dc double probe instrument on Explorer 45 was used to identify the plasmapause. A data base was developed to statistically study the average position of the plasmapause over 14.5 hours of magnetic local time under differing magnetic conditions. The afternoon-evening bulge in the L coordinate of the plasmapause versus local time was found centered between 20 and 21 hours MLT during magnetically quiet periods and shifted toward dusk as activity increased, but always post dusk. During quiet periods a bulge in the L coordinate near noon was also seen, which disappeared as activity increased. The average local time distribution plasmapause position during high magnetic activity was irregular in the afternoon region where large scale convection <span class="hlt">models</span> predict the creation of plasmatails or detached plasma regions from increases in the solar wind induced convection. The results suggest that solar wind induced convection is partially shielded from the dayside. As the intensity of the convection is increased, it more effectively penetrates the dayside, which shifts the post dusk bulge nearer to dusk and eliminates the quiet-time bulge near noon.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/20819476','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/20819476"><span id="translatedtitle">Fechner's aesthetics <span class="hlt">revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Phillips, Flip; Norman, J Farley; Beers, Amanda M</p> <p>2010-01-01</p> <p>Gustav Fechner is widely respected as a founding father of experimental psychology and psychophysics but fewer know of his interests and work in empirical aesthetics. In the later 1800s, toward the end of his career, Fechner performed experiments to empirically evaluate the beauty of rectangles, hypothesizing that the preferred shape would closely match that of the so-called 'golden rectangle'. His findings confirmed his suspicions, but in the intervening decades there has been significant evidence pointing away from that finding. Regardless of the results of this one study, Fechner ushered in the notion of using a metric to evaluate beauty in a psychophysical way. In this paper, we recreate the experiment using more naturalistic stimuli. We evaluate subjects' preferences against <span class="hlt">models</span> that use various types of object complexity as metrics. Our findings that subjects prefer either very simple or very complex objects runs contrary to the hypothesized results, but are systematic none the less. We conclude that there are likely to be useful measures of aesthetic preference but they are likely to be complicated by the difficulty in defining some of their constituent parts. PMID:20819476</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/460077','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/460077"><span id="translatedtitle">The Oquirrh basin <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Erskine, M.C.</p> <p>1997-04-01</p> <p>The upper Paleozoic succession in the Oquirrh basin in unusually thick, up to 9300 m, and consists mainly of a Pennsylvanian-middle Permian miogeocline of northwestern Utah. Previous workers have suggested a tectonic origin for the Oquirrh basin that is incompatible with the basin location in both time and space. There is no evidence for Pennsylvanian and Lower Permian tectonism in the middle of the miogeocline. Thermal evidence from the Mississippian Mission Canyon shale does no support the implied deep burial of the crustal sag <span class="hlt">models</span> of basin formation. Stratigraphic and facies evidence indicates a growth fault origin for the basin. Regional isopach maps and facies maps are powerful tools in interpreting depositional environments and in reconstructing fold-and-thrust belts. However, the location of measured sections relative to the location of the growth fault basin. The Charleston-Nebo thrust may have essentially reversed the movement on a growth fault. Thick Oquirrh basin sedimentary rocks may not be required to balance structural sections across this thrust fault. A thin-skinned, extensional growth fault origin for the Oquirrh basin implies that the Cordilleran miogeocline did not participate in the Pennsylvanian north-vergent uplifts of the Ancestral Rocky Mountains.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1999AAS...19410404M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1999AAS...19410404M"><span id="translatedtitle">SS Lac <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Milone, E. F.; Schiller, S. J.; Munari, U.; Kallrath, J.</p> <p>1999-05-01</p> <p>We have evidence confirming changes in light curve amplitude of the former eclipsing and current SB2 system SS Lac in the open cluster NGC 7209. Remeasured Harvard plate data and published and compiled data sets reveal that the depth of the primary minimum increased between the 1890s and early 1900s and decreased in the 1920s and 1930s. Peak fittings of the amplitude with phase suggests a peak amplitude centered ca. 1911.5, with eclipse onset at about 1885 and effective eclipse cessation late in 1937. We thus concur with the findings of Lehmann (IBVS 3610, 1991), that the apparent inclination varies with time and that a central eclipse occurred about 1911, and of Mossakovskaya (Astron. Lett., 19, 35, 1993), that eclipses ceased prior to 1940. Estimates of SS Lac from plates taken at Tashkent between 1937 and 1940 serve to confirm these results. We have completed now an exhaustive study of the radial velocity curves of Tomasella & Munari (1998, A&A, 335, 561) and all three potentially useful archival light curves available to us, and will discuss the implications of the solutions for <span class="hlt">models</span> of the system and the cluster to which it belongs. This work was supported in part by grants to Milone from NSERC of Canada, and the URGC of the University of Calgary.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3763044','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3763044"><span id="translatedtitle">Selective leptin resistance <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p></p> <p>2013-01-01</p> <p>In addition to effects on appetite and metabolism, leptin influences many neuroendocrine and physiological systems, including the sympathetic nervous system. Building on my Carl Ludwig Lecture of the American Physiological Society, I review the sympathetic and cardiovascular actions of leptin. The review focuses on a critical analysis of the concept of selective leptin resistance (SLR) and the role of leptin in the pathogenesis of obesity-induced hypertension in both experimental animals and humans. We introduced the concept of SLR in 2002 to explain how leptin might increase blood pressure (BP) in obese states, such as diet-induced obesity (DIO), that are accompanied by partial leptin resistance. This concept, analogous to selective insulin resistance in the metabolic syndrome, holds that in several genetic and acquired <span class="hlt">models</span> of obesity, there is preservation of the renal sympathetic and pressor actions of leptin despite attenuation of the appetite and weight-reducing actions. Two potential overlapping mechanisms of SLR are reviewed: 1) differential leptin molecular signaling pathways that mediate selective as opposed to universal leptin action and 2) brain site-specific leptin action and resistance. Although the phenomenon of SLR in DIO has so far focused on preservation of sympathetic and BP actions of leptin, consideration should be given to the possibility that this concept may extend to preservation of other actions of leptin. Finally, I review perplexing data on the effects of leptin on sympathetic activity and BP in humans and its role in human obesity-induced hypertension. PMID:23883674</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007SGeo...28....1D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007SGeo...28....1D"><span id="translatedtitle">Forensic seismology <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Douglas, A.</p> <p>2007-01-01</p> <p>The first technical discussions, held in 1958, on methods of verifying compliance with a treaty banning nuclear explosions, concluded that a monitoring system could be set up to detect and identify such explosions anywhere except underground: the difficulty with underground explosions was that there would be some earthquakes that could not be distinguished from an explosion. The development of adequate ways of discriminating between earthquakes and underground explosions proved to be difficult so that only in 1996 was a Comprehensive Nuclear Test Ban Treaty (CTBT) finally negotiated. Some of the important improvements in the detection and identification of underground tests—that is in forensic seismology—have been made by the UK through a research group at the Atomic Weapons Establishment (AWE). The paper describes some of the advances made in identification since 1958, particularly by the AWE Group, and the main features of the International Monitoring System (IMS), being set up to verify the Test Ban. Once the Treaty enters into force, then should a suspicious disturbance be detected the State under suspicion of testing will have to demonstrate that the disturbance was not a test. If this cannot be done satisfactorily the Treaty has provisions for on-site inspections (OSIs): for a suspicious seismic disturbance for example, an international team of inspectors will search the area around the estimated epicentre of the disturbance for evidence that a nuclear test really took place. Early observations made at epicentral distances out to 2,000 km from the Nevada Test Site showed that there is little to distinguish explosion seismograms from those of nearby earthquakes: for both source types the short-period (SP: ˜1 Hz) seismograms are complex showing multiple arrivals. At long range, say 3,000 10,000 km, loosely called teleseismic distances, the AWE Group noted that SP P waves—the most widely and well-recorded waves from underground explosions—were in contrast simple, comprising one or two cycles of large amplitude followed by a low-amplitude coda. Earthquake signals on the other hand were often complex with numerous arrivals of similar amplitude spread over 35 s or more. It therefore appeared that earthquakes could be recognised on complexity. Later however, complex explosion signals were observed which reduced the apparent effectiveness of complexity as a criterion for identifying earthquakes. Nevertheless, the AWE Group concluded that for many paths to teleseismic distances, Earth is transparent for P signals and this provides a window through which source differences will be most clearly seen. Much of the research by the Group has focused on understanding the influence of source type on P seismograms recorded at teleseismic distances. Consequently the paper concentrates on teleseismic methods of distinguishing between explosions and earthquakes. One of the most robust criteria for discriminating between earthquakes and explosions is the m b : M s criterion which compares the amplitudes of the SP P waves as measured by the body-wave magnitude m b, and the long-period (LP: ˜0.05 Hz) Rayleigh-wave amplitude as measured by the surface-wave magnitude M s; the P and Rayleigh waves being the main wave types used in forensic seismology. For a given M s, the m b for explosions is larger than for most earthquakes. The criterion is difficult to apply however, at low magnitude (say m b < 4.5) and there are exceptions—earthquakes that look like explosions. A difficulty with identification criteria developed in the early days of forensic seismology was that they were in the main empirical—it was not known why they appeared to work and if there were test sites or earthquakes where they would fail. Consequently the AWE Group in cooperation with the University of Cambridge used seismogram <span class="hlt">modelling</span> to try and understand what controls complexity of SP P seismograms, and to put the m b : M s criterion on a theoretical basis. The results of this work show that the m b : M s criterion is robust because several factors contribute to the separation of earthquakes and explosions. The principal reason for the separation however, is that for many orientations of the earthquake source there is at least one P nodal plane in the teleseismic window and this biases m b low. Only for earthquakes with near 45° dip-slip mechanisms where the antinode of P is in the source window is the m b: M s criterion predicted to fail. The results from <span class="hlt">modelling</span> are consistent with observation—in particular there are earthquakes, “anomalous events”, which look explosion-like on the m b: M s criterion, that turn out to have mechanisms close to 45° dip-slip. Fortunately the P seismograms from such earthquakes usually show pP and sP, the reflections from the free surface of P and S waves radiated upwards. From the pP P and sP P times the focal depth can be estimated. So far the estimated depth of the anomalous events have turned out to be ˜20 km, too deep to be explosions. Studies show that the observation that P seismograms are more complex than predicted by simple <span class="hlt">models</span> can be explained on the weak-signal hypothesis: the standard phases, direct P and the surface reflections, are weak because of amongst other things, the effects of the radiation pattern or obstacles on the source-to-receiver path; other non-standard arrivals then appear relatively large on the seismograms. What has come out of the <span class="hlt">modelling</span> of P seismograms is a criterion for recognising suspicious disturbances based on simplicity rather than complexity. Simple P seismograms for earthquakes at depths of more than a few kilometres are likely to be radiated only to stations that lie in a confined range of azimuths and distances. If then, simple seismograms are recorded over a wide range of distances and particularly azimuths, it is unlikely the source is an earthquake at depth. It is possible to test this using the relative amplitudes of direct P and later arrivals that might be surface reflections. The procedure is to use only the simple P seismograms on the assumption that whereas the propagation through Earth may make a signal more complex it is unlikely to make it simpler. From the amplitude of the coda of these seismograms, bounds can be placed on the size of possible pP and sP. The relative-amplitude method is then used to search for orientations of the earthquake source that are compatible with the observations. If no such orientations are found the source must be shallow so that any surface reflections merge with direct P, and hence could be an explosion. The IMS when completed will be a global network of 321 monitoring stations, including 170 seismological stations principally to detect the seismic waves from earthquakes and underground explosions. The IMS will also have stations with hydrophones, microbarographs and radionuclide detectors to detect explosions in the oceans and the atmosphere and any isotopes in the air characteristic of a nuclear test. The Global Communications Infrastructure provides communications between the IMS stations and the International Data Centre (IDC), Vienna, where the recordings from the monitoring stations is collected, collated, and analysed. The IDC issues bulletins listing geophysical disturbances, to States Signatories to the CTBT. The assessment of the disturbances to decide whether any are possible explosions, is a task for State Signatories. For each Signatory to do a detailed analysis of all disturbances would be expensive and time consuming. Fortunately many disturbances can be readily identified as earthquakes and removed from consideration—a process referred to as “event screening”. For example, many earthquakes with epicentres over the oceans can be distinguished from underwater explosions, because an explosion signal is of much higher frequency than that of earthquakes that occur below the ocean bed. Further, many earthquakes could clearly be identified at the IDC on the m b : M s criterion, but there is a difficulty—how to set the decision line. The possibility has to be very small that an explosion will be classed by mistake, as an earthquake. The decision line has therefore to be set conservatively, consequently with routine application of current screening criteria, only about 50% of earthquakes can be positively identified as such. Various methods have been proposed whereby a “determined violator” could avoid the provisions of a CTBT and carry out a test that would be either undetected or detected but not identified as an explosion. The increase in complexity and cost of such a test should discourage any State from attempting it. In addition, there is always the possibility of some stations detecting the test, the test being identified as suspicious, and so subject to an OSI. With time as the IMS becomes more efficient and effective it will act increasingly to deter anyone contemplating a clandestine test, from going ahead. What has emerged is several robust criteria. The criteria include: location, which when combined with hydro-acoustic data can identify earthquakes under the sea; m b : M s; and depth of focus. More detailed study is required of any remaining seismic disturbance that is regarded as suspicious: for example, is close to a site where nuclear tests have been carried out in the past. Any disturbance that is shown to be explosion-like, may be the subject of an OSI. One surprise is how little plate tectonics has contributed to resolving problems in forensic seismology. Much of the evidence for plate tectonics comes from seismological studies so it would be expected that the implications for Earth structure arising from forensic seismology would be consistent with plate-tectonic <span class="hlt">models</span>. So far the AWE Group have found little synergy between plate tectonics and forensic seismology. It is to be hoped that the large volume of seismological data of high quality now being collected by the IMS and the increasing number of digital stations, will result in a revised Earth <span class="hlt">model</span> that is consistent with the findings of forensic seismology, so that a future review of progress will show that the forensic seismologist can draw on this <span class="hlt">model</span> in attempting to interpret apparently anomalous seismograms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26394627','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26394627"><span id="translatedtitle">The Baroreflex Mechanism <span class="hlt">Revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Rabinovitch, A; Friedman, M; Braunstein, D; Biton, Y; Aviram, I</p> <p>2015-08-01</p> <p>We state that the autonomic part of the brain controls the blood pressure (BP) and the heart rate (HR) via the baroreflex mechanism in all situations of human activity (at sleep, at rest, during exercise, fright etc.), in a way which is not, as was hitherto assumed, a mere homeostatic tool or even a resetting device, designed to bring these variables on the road to preset values. The baroreflex is rather a continuous feedback mechanism commanded by the autonomic part of the brain, leading to values appropriate to the situation at hand. Feasibility of this assertion is demonstrated here by using the Seidel-Herzel feedback system outside of its regular practice. Results show indeed that the brain can, and we claim that it does, control the HR and BP throughout life. New responses are demonstrated, e.g., to a sudden fear or apnea. In this event, large BP and HR overshoots are expected before the variables can relax to a new level. Response to abrupt downward change in the controlling parameter shows an undershoot in HR and just a gradual resetting in the BP. The relaxation from sudden external changes to various expected states are calculated and discussed and properties of the Rheos test are explained. Experimental findings for orthostatic tests and for babies under translations and rotations reveal complete qualitative agreement with our <span class="hlt">model</span> and show no need to invoke the operation of additional body systems. Our method should be the preferred one by the Occam Razor approach. The outcomes may lead to beneficial clinical implication. PMID:26394627</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/22819479','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/22819479"><span id="translatedtitle">Bhopal atmospheric dispersion <span class="hlt">revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Havens, Jerry; Walker, Heather; Spicer, Tom</p> <p>2012-09-30</p> <p>There is a vital need to understand details of the methylisocyanate (MIC) release that occurred at the 1984 Union Carbide Ltd. pesticide plant in Bhopal, India in order to avoid or respond to such releases in the future. However, we believe there are serious deficiencies in currently available dispersion predictions of the impact of toxic materials on humans and animals downwind of the plant. Specifically, cloud densities have been underestimated due to failure to account for the presence of a liquid/solid aerosol that would have been produced by the chemical reactions that caused the problem. Using data reported in Union Carbide's own investigation of the accident, which included chemical reaction data, we estimated aerosol compositions and cloud densities, then <span class="hlt">modeled</span> the Bhopal release, simulating potential exposure levels at various locations under a number of wind-condition scenarios. For the worst-case (low wind speed and high aerosol densities), our predicted MIC concentrations at ground level are at least one order of magnitude greater than any previously published estimates. The centerline elevation of the jetting plume released at 33 m elevation is predicted to rise to about 41 m before falling, resulting in a 40 ppm (Immediately Dangerous to Life or Health, IDLH) concentration contour that reaches the ground at about 410 m downwind of the release location. This is consistent with observations that the plant environs were not hard-hit while the public immediately downwind of the plant perimeter was severely exposed. Concentrations on the order of 1000 ppm are predicted at some ground-level locations, which are more consistent than previous estimates with the reported large numbers of deaths and injuries of humans and animals. PMID:22819479</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/8838726','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/8838726"><span id="translatedtitle">Suture anchor strength <span class="hlt">revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Barber, F A; Herbert, M A; Click, J N</p> <p>1996-02-01</p> <p>The rapid proliferation of suture anchors continues. Our prior report on the pullout strength of 14 different anchors is supplemented by a similar test conducted on 8 additional anchors. Comparative data on modes of failure and failure strengths (ultimate loads to failure) for these new devices are compared statistically with the previously tested anchors. In a fresh never-frozen porcine femur <span class="hlt">model</span>, 10 samples of each of the additional anchors tested were threaded with stainless steel sutures and inserted into three different test areas (diaphyseal cortex, metaphyseal cortex, and a cancellous trough). Tensile stress parallel to the axis of insertion was applied at a rate of 12.5 mm/s by an Instron 1321 testing machine (Instron Corp, Canton, MA) until failure and mean anchor failure strengths calculated. The anchors tested were the Mitek G2 as a control, miniMitek, Mitek Superanchor, Mitek Rotator Cuff anchor (Mitek Products, Westwood, MA), Innovasive Devices Radial Osteal Compression device (Innovasive Devices, Hopkinton, MA), Arthrex Fastak (Arthrex Inc, Naples, FL), Arthrotek miniHarpoon (Arthrotek, Warsaw, IN), Orthopedic Biosystems PeBA 3 and PeBA 5 (Orthopedic Biosystems, Scottsdale, AZ), and AME 5.5 screw (American Medical Electronics, Richardson, TX). Failure mode (anchor pullout, suture eyelet cut out, or wire breakage) was generally consistent for each anchor type. The size of insertion hole is clinically important and each anchor's performance was evaluated as a function of its minor diameter or drill hole. For screw anchors, the larger the minor diameter of the screw, the higher the mean failure strengths in all three test areas (P = .001). However, larger drill holes for non-screw anchors resulted in lower mean failure strengths in cancellous bone (P = .03) and diaphyseal cortex (P < .005). PMID:8838726</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/923295','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/923295"><span id="translatedtitle">The Lanthanide Contraction <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Seitz, Michael; Oliver, Allen G.; Raymond, Kenneth N.</p> <p>2007-04-19</p> <p>A complete, isostructural series of lanthanide complexes (except Pm) with the ligand TREN-1,2-HOIQO has been synthesized and structurally characterized by means of single-crystal X-ray analysis. All complexes are 1D-polymeric species in the solid state, with the lanthanide being in an eight-coordinate, distorted trigonal-dodecahedral environment with a donor set of eight unique oxygen atoms. This series constitutes the first complete set of isostructural lanthanide complexes with a ligand of denticity greater than two. The geometric arrangement of the chelating moieties slightly deviates across the lanthanide series, as analyzed by a shape parameter metric based on the comparison of the dihedral angles along all edges of the coordination polyhedron. The apparent lanthanide contraction in the individual Ln-O bond lengths deviates considerably from the expected quadratic decrease that was found previously in a number of complexes with ligands of low denticity. The sum of all bond lengths around the trivalent metal cation, however, is more regular, showing an almost ideal quadratic behavior across the entire series. The quadratic nature of the lanthanide contraction is derived theoretically from Slater's <span class="hlt">model</span> for the calculation of ionic radii. In addition, the sum of all distances along the edges of the coordination polyhedron show exactly the same quadratic dependency as the Ln-X bond lengths. The universal validity of this coordination sphere contraction, concomitant with the quadratic decrease in Ln-X bond lengths, was confirmed by reexamination of four other, previously published, almost complete series of lanthanide complexes. Due to the importance of multidentate ligands for the chelation of rare-earth metals, this result provides a significant advance for the prediction and rationalization of the geometric features of the corresponding lanthanide complexes, with great potential impact for all aspects of lanthanide coordination.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=+%22creative+economy+ecosystem%22+OR+%22creative+ideas%22++OR+%22innovation+in+education%22++OR+%22online+learning+capabilities%22++OR+%22digital+education%22++OR+%22new+methods+of+learning%22++OR+%22online+gaming+education%22+&id=EJ1026986','ERIC'); return false;" href="http://eric.ed.gov/?q=+%22creative+economy+ecosystem%22+OR+%22creative+ideas%22++OR+%22innovation+in+education%22++OR+%22online+learning+capabilities%22++OR+%22digital+education%22++OR+%22new+methods+of+learning%22++OR+%22online+gaming+education%22+&id=EJ1026986"><span id="translatedtitle"><span class="hlt">Revisiting</span> Mednick's <span class="hlt">Model</span> on Creativity-Related Differences in Associative Hierarchies. Evidence for a Common Path to Uncommon Thought</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Benedek, Mathias; Neubauer, Aljoscha C.</p> <p>2013-01-01</p> <p>Fifty years ago, Mednick ["Psychological Review", 69 (1962) 220] proposed an elaborate <span class="hlt">model</span> that aimed to explain how creative ideas are generated and why creative people are more likely to have creative ideas. The <span class="hlt">model</span> assumes that creative people have flatter associative hierarchies and as a consequence can more fluently retrieve</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_20 --> <div id="page_21" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="401"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=+%22creative+economy+ecosystem%22+OR+%22creative+ideas%22++OR+%22innovation+in+education%22++OR+%22online+learning+capabilities%22++OR+%22digital+education%22++OR+%22new+methods+of+learning%22++OR+%22online+gaming+education%22++OR+%22new+methods+of+teaching%22+&pg=2&id=EJ1026986','ERIC'); return false;" href="http://eric.ed.gov/?q=+%22creative+economy+ecosystem%22+OR+%22creative+ideas%22++OR+%22innovation+in+education%22++OR+%22online+learning+capabilities%22++OR+%22digital+education%22++OR+%22new+methods+of+learning%22++OR+%22online+gaming+education%22++OR+%22new+methods+of+teaching%22+&pg=2&id=EJ1026986"><span id="translatedtitle"><span class="hlt">Revisiting</span> Mednick's <span class="hlt">Model</span> on Creativity-Related Differences in Associative Hierarchies. Evidence for a Common Path to Uncommon Thought</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Benedek, Mathias; Neubauer, Aljoscha C.</p> <p>2013-01-01</p> <p>Fifty years ago, Mednick ["Psychological Review", 69 (1962) 220] proposed an elaborate <span class="hlt">model</span> that aimed to explain how creative ideas are generated and why creative people are more likely to have creative ideas. The <span class="hlt">model</span> assumes that creative people have flatter associative hierarchies and as a consequence can more fluently retrieve…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AGUFM.U21B0422H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AGUFM.U21B0422H"><span id="translatedtitle">Allegre's Lead Paradox <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hofmann, A. W.; Goldstein, S. L.; Class, C.</p> <p>2007-12-01</p> <p>Allegre (1969), using a generalized Concordia plot, was first to note that in a 4.55 Ga old Earth, Pb has been removed from the mantle in preference to U, even though magmatism tends to do the opposite. He noted that this "contradiction" might require a separate reservoir where the missing lead is stored. This "contradiction", more commonly expressed by the conventional Holmes-Houtermans diagram, has become known as the "lead paradox." Several <span class="hlt">models</span> have been proposed to resolve it, ranging from late "core pumping" of Pb (as suggested by Allgre) to Pb storage in the mantle transition zone (Murphy et al. 2003) or in ancient parts of the lower continental crust. The idea of late core pumping has recently been revived by Wood & Halliday (2005) who suggested that Pb was sequestered through late sulfide segregation into the core. Here we propose that crystallization of Ca-perovskite, accompanied by segregation of a dense silicate melt toward the core-mantle boundary, can account for the apparently elevated U/Pb ratio of the accessible silicate Earth, particularly if the partition coefficient for U and Th in Ca-perovskite is as high as 400 as suggested by Corgne and Wood (2005). Such a dense liquid is the inferred consequence of the measured crossover of melting temperatures of silicate perovskite and ferro-periclase at about 1200 km depth, and the predicted Fe-rich eutectic and low melting temperatures in the lowermost mantle (Boehler, 2000). In addition, lower-mantle melt segregation with residual Ca-perovskite will cause a decrease in Nb/Ta from the primitive (chondritic) value in the accessible mantle, another, more recently discovered puzzle of mantle geochemistry. Downward segregation of a dense melt fraction and final solidification of the lowermost mantle may have been a slow process requiring more than 100 Ma, and involving a substantial fraction of the mantle. We suggest that this process served to stabilize the D'' reservoir storing solar noble gases (Tolstikhin & Hofmann, 2005) and subchondritic 142Nd/144Nd ratios (Boyet & Carlson, 2005), which these authors have ascribed to subduction of a primordial crust at an even earlier stage. Allegre, C.A. (1969) Earth Planet. Sci. Lett. 5, 261-269. Boehler, R. (2000) Reviews Geophys. 38, 221-235. Murphy, D.T. et al. (2003) J. Petrol. 44, 39-53. Tolstikhin, I.N. & Hofmann, A.W. (2005) Phys. Earth Planet. Int. 148, 109-130. Boyet, M. & Carlson, R.W. (2005) Science 309, 576-581. Corgne, A & Wood, B.J. (2005) Contrib. Min. Pet. 149, 85-97.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFM.B41F0259M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFM.B41F0259M"><span id="translatedtitle">Fire and Ice <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Macdonald, F. A.; Rooney, A.; Dudas, F. O.; Schmitz, M. D.</p> <p>2011-12-01</p> <p>Recent U-Pb ID-TIMS ages from NW Canada demonstrate a rough coincidence between the Franklin LIP and the initiation of the Sturtian glaciation(s). These events could be mechanistically related through an increase in weatherability of the continents and/or from an increase in planetary albedo. Both of these scenarios have predictions for the relative timing of the emplacement of the Franklin LIP and the onset of glaciations and for the Sr and Os composition of seawater. We report new Re/Os and U-Pb ID-TIMS zircon ages and Sr, Os, and C isotope results from Mongolia and northwest Canada. These data suggest: 1) The Islay carbon isotope anomaly in NW Canada is separated from the onset of the Sturtian glaciation(s) by >10 Myrs and is thus not directly related to the initiation of glaciations. 2) The Os isotopic composition of pre-Rapitan (Sturtian) sediments in NW Canada is remarkably unradiogenic, consistent with intense basalt weathering; however, it is uncertain if these strata were in full communication with the global ocean. 3) The Sr isotopic composition of pre-Strutian sediments on multiple continents also show a decrease leading into the glaciations, again consistent with an increase in basalt weathering prior to the glaciations. 4) The Os isotope composition of the post-glacial Twitya Formation in NW Canada is much more radiogenic than pre-glacial strata and likely reflects intense weathering of the continental crust associated with the deglaciation. 5) The Sr isotopic composition of seawater increases rapidly after both the Sturtian and Marinoan glaciations and is otherwise relatively stable in the Cryogenian, testifying to the extreme effect of the glaciations on the Sr isotopic composition of seawater. 6) The only other inflection in our new high-resolution Cryogenian Sr isotope curve occurs across the Tayshir carbon isotope anomaly, confirming links between the carbon cycle and continental weathering. 7) Current age constraints suggest a long duration of the Sturtian glaciation(s), >10 Myr. Together, these data give legs to the 'Fire and Ice' hypothesis of Godderis et al., 2003, and indicate major changes in weathering proxies on million-year timescales both before and after the Sturtian glaciations(s). However, it remains possible that the increased weatherability merely set the stage for global glaciations, leaving the Earth more vulnerable to a sudden change in insolation. Further precise ages and <span class="hlt">modeling</span> will shed additional light on the initiation mechanism of Snowball Earth.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21513039','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21513039"><span id="translatedtitle">Axion cosmology <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Wantz, Olivier; Shellard, E. P. S.</p> <p>2010-12-15</p> <p>The misalignment mechanism for axion production depends on the temperature-dependent axion mass. The latter has recently been determined within the interacting instanton liquid <span class="hlt">model</span>, and provides for the first time a well-motivated axion mass for all temperatures. We reexamine the constraints placed on the axion parameter space in the light of this new mass function. Taking this mass at face value, we find an accurate and updated constraint f{sub a{<=}}2.8({+-}2)x10{sup 11} GeV or m{sub a{>=}}21({+-}2) {mu}eV from the misalignment mechanism in the classic axion window (thermal scenario). However, this is superseded by axion string radiation which leads to f{sub a} < or approx. 3.2{sub -2}{sup +4}x10{sup 10} GeV or m{sub a} > or approx. 0.20{sub -0.1}{sup +0.2} meV. In this analysis, we take care to precisely compute the effective degrees of freedom and, to fill a gap in the literature, we present accurate fitting formulas. We solve the evolution equations exactly, and find that analytic results used to date generally underestimate the full numerical solution by a factor 2-3. In the inflationary scenario, axions induce isocurvature fluctuations and constrain the allowed inflationary scale H{sub I}. Taking anharmonic effects into account, we show that these bounds are actually weaker than previously computed. Considering the fine-tuning issue of the misalignment angle in the whole of the anthropic window, we derive new bounds which open up the inflationary window near {theta}{sub a{yields}{pi}}. In particular, we find that inflationary dark matter axions can have masses as high as 0.01-1 meV, covering the whole thermal axion range, with values of H{sub I} up to 10{sup 9} GeV. Quantum fluctuations during inflation exclude dominant dark matter axions with masses above m{sub a} < or approx. 1 meV.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4081714','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4081714"><span id="translatedtitle">The cognitive-interpersonal maintenance <span class="hlt">model</span> of anorexia nervosa <span class="hlt">revisited</span>: a summary of the evidence for cognitive, socio-emotional and interpersonal predisposing and perpetuating factors</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p></p> <p>2013-01-01</p> <p>Aim To describe the evidence base relating to the Cognitive-Interpersonal Maintenance <span class="hlt">Model</span> for anorexia nervosa (AN). Background A Cognitive-Interpersonal Maintenance <span class="hlt">Model</span> maintenance <span class="hlt">model</span> for anorexia nervosa was described in 2006. This <span class="hlt">model</span> proposed that cognitive, socio-emotional and interpersonal elements acted together to both cause and maintain eating disorders. Method A review of the empirical literature relating to the key constructs of the <span class="hlt">model</span> (cognitive, socio-emotional, interpersonal) risk and maintaining factors for anorexia nervosa was conducted. Results Set shifting and weak central coherence (associated with obsessive compulsive traits) have been widely studied. There is some evidence to suggest that a strong eye for detail and weak set shifting are inherited vulnerabilities to AN. Set shifting and global integration are impaired in the ill state and contribute to weak central coherence. In addition, there are wide-ranging impairments in socio-emotional processing including: an automatic bias in attention towards critical and domineering faces and away from compassionate faces; impaired signalling of, interpretation and regulation of emotions. Difficulties in social cognition may in part be a consequence of starvation but inherited vulnerabilities may also contribute to these traits. The shared familial traits may accentuate family members tendency to react to the frustrating and frightening symptoms of AN with high expressed emotion (criticism, hostility, overprotection), and inadvertently perpetuate the problem. Conclusion The cognitive interpersonal <span class="hlt">model</span> is supported by accumulating evidence. The <span class="hlt">model</span> is complex in that cognitive and socio-emotional factors both predispose to the illness and are exaggerated in the ill state. Furthermore, some of the traits are inherited vulnerabilities and are present in family members. The clinical formulations from the <span class="hlt">model</span> are described as are new possibilities for targeted treatment. PMID:24999394</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4623502','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4623502"><span id="translatedtitle">The Balance-Scale Task <span class="hlt">Revisited</span>: A Comparison of Statistical <span class="hlt">Models</span> for Rule-Based and Information-Integration Theories of Proportional Reasoning</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Hofman, Abe D.; Visser, Ingmar; Jansen, Brenda R. J.; van der Maas, Han L. J.</p> <p>2015-01-01</p> <p>We propose and test three statistical <span class="hlt">models</span> for the analysis of children’s responses to the balance scale task, a seminal task to study proportional reasoning. We use a latent class <span class="hlt">modelling</span> approach to formulate a rule-based latent class <span class="hlt">model</span> (RB LCM) following from a rule-based perspective on proportional reasoning and a new statistical <span class="hlt">model</span>, the Weighted Sum <span class="hlt">Model</span>, following from an information-integration approach. Moreover, a hybrid LCM using item covariates is proposed, combining aspects of both a rule-based and information-integration perspective. These <span class="hlt">models</span> are applied to two different datasets, a standard paper-and-pencil test dataset (N = 779), and a dataset collected within an online learning environment that included direct feedback, time-pressure, and a reward system (N = 808). For the paper-and-pencil dataset the RB LCM resulted in the best fit, whereas for the online dataset the hybrid LCM provided the best fit. The standard paper-and-pencil dataset yielded more evidence for distinct solution rules than the online data set in which quantitative item characteristics are more prominent in determining responses. These results shed new light on the discussion on sequential rule-based and information-integration perspectives of cognitive development. PMID:26505905</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/24070292','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/24070292"><span id="translatedtitle"><span class="hlt">Revisiting</span> a many-body <span class="hlt">model</span> for water based on a single polarizable site: from gas phase clusters to liquid and air/liquid water systems.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ral, Florent; Vallet, Valrie; Flament, Jean-Pierre; Masella, Michel</p> <p>2013-09-21</p> <p>We present a revised version of the water many-body <span class="hlt">model</span> TCPE [M. Masella and J.-P. Flament, J. Chem. Phys. 107, 9105 (1997)], which is based on a static three charge sites and a single polarizable site to <span class="hlt">model</span> the molecular electrostatic properties of water, and on an anisotropic short range many-body energy term specially designed to accurately <span class="hlt">model</span> hydrogen bonding in water. The parameters of the revised <span class="hlt">model</span>, denoted TCPE/2013, are here developed to reproduce the ab initio energetic and geometrical properties of small water clusters (up to hexamers) and the repulsive water interactions occurring in cation first hydration shells. The <span class="hlt">model</span> parameters have also been refined to reproduce two liquid water properties at ambient conditions, the density and the vaporization enthalpy. Thanks to its computational efficiency, the new <span class="hlt">model</span> range of applicability was validated by performing simulations of liquid water over a wide range of temperatures and pressures, as well as by investigating water liquid/vapor interfaces over a large range of temperatures. It is shown to reproduce several important water properties at an accurate enough level of precision, such as the existence liquid water density maxima up to a pressure of 1000 atm, the water boiling temperature, the properties of the water critical point (temperature, pressure, and density), and the existence of a "singularity" temperature at about 225 K in the supercooled regime. This <span class="hlt">model</span> appears thus to be particularly well-suited for characterizing ion hydration properties under different temperature and pressure conditions, as well as in different phases and interfaces. PMID:24070292</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=telephone&pg=7&id=EJ912556','ERIC'); return false;" href="http://eric.ed.gov/?q=telephone&pg=7&id=EJ912556"><span id="translatedtitle"><span class="hlt">Re-Visiting</span> College Students' Attitudes toward the Internet-Based on a 6-T <span class="hlt">Model</span>: Gender and Grade Level Difference</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Chou, Chien; Wu, Huan-Chueh; Chen, Chao-Hsiu</p> <p>2011-01-01</p> <p>The purpose of this study is to propose a 6-T <span class="hlt">model</span> (Tool, Toy, Telephone, Territory, Treasure of Information, and Trade) to explore college students' Internet-related attitudes, and to examine whether gender and grade level make any difference in their attitudes. Data from 1069 participants were collected from 96 Taiwanese universities and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26136150','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26136150"><span id="translatedtitle"><span class="hlt">Re-visiting</span> the nature and relationships between neurological signs and neurocognitive functions in first-episode schizophrenia: An invariance <span class="hlt">model</span> across time.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Chan, Raymond C K; Dai, Shan; Lui, Simon S Y; Ho, Karen K Y; Hung, Karen S Y; Wang, Ya; Geng, Fu-lei; Li, Zhi; Cheung, Eric F C</p> <p>2015-01-01</p> <p>The present study examined different types of neurological signs in patients with first-episode schizophrenia and their relationships with neurocognitive functions. Both cross-sectional and longitudinal designs were adopted with the use of the abridged Cambridge Neurological Inventory which comprises items capturing motor coordination, sensory integration and disinhibition. A total of 157 patients with first-episode schizophrenia were assessed at baseline and 101 of them were re-assessed at six-month interval. A structural equation <span class="hlt">model</span> (SEM) with invariance <span class="hlt">model</span> across time was used for data analysis. The <span class="hlt">model</span> fitted well with the data at baseline assessment, X^2(21) = 21.78, p = 0.413, NFI = 0.95, NNFI = 1.00, CFI = 1.00, IFI = 1.00, RMSEA = 0.015. Subsequent SEM analysis with invariance <span class="hlt">model</span> at six-month interval also demonstrated the same stable pattern across time and showed strong measurement invariance and structure invariance across time. Our findings suggest that neurological signs capture more or less the same construct captured by conventional neurocognitive tests in patients with schizophrenia. The measurement and structure of these relationships appear to be stable over time. PMID:26136150</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26771029','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26771029"><span id="translatedtitle">Where does methanol lose hydrogen to trigger steam reforming? A <span class="hlt">revisit</span> of methanol dehydrogenation on the PdZn alloy <span class="hlt">model</span> obtained from kinetic Monte Carlo simulations.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Cheng, Feng; Chen, Zhao-Xu</p> <p>2016-01-27</p> <p>Pd/ZnO is a promising catalyst studied for methanol steam reforming (MSR) and the 1?:?1 PdZn alloy is demonstrated to be the active component. It is believed that MSR starts from methanol dehydrogenation to methoxy. Previous studies of methanol dehydrogenation on the ideal PdZn(111) surface show that methanol adsorbs weakly on the PdZn(111) surface and it is hard for methanol to transform into methoxy because of the high dehydrogenation barrier, indicating that the catalyst <span class="hlt">model</span> is not appropriate for investigating the first step of MSR. Using the <span class="hlt">model</span> derived from our recent kinetic Monte Carlo simulations, we examined the process CH3OH ? CH3O ? CH2O ? CHO ? CO. Compared with the ideal <span class="hlt">model</span>, methanol adsorbs much more strongly and the barrier from CH3OH ? CH3O is much lower on the kMC <span class="hlt">model</span>. On the other hand, the C-H bond breaking of CH3O, CH2O and CHO becomes harder. We show that co-adsorbed water is important for refreshing the active sites. The present study shows that the first MSR step most likely takes place on three-fold hollow sites formed by Zn atoms, and the inhomogeneity of the PdZn alloy may exert significant influences on reactions. PMID:26771029</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=kaplan&pg=7&id=EJ630379','ERIC'); return false;" href="http://eric.ed.gov/?q=kaplan&pg=7&id=EJ630379"><span id="translatedtitle">Self-Esteem and Delinquency <span class="hlt">Revisited</span> (Again): A Test of Kaplan's Self-Derogation Theory of Delinquency Using Latent Growth Curve <span class="hlt">Modeling</span>.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Mason, W. Alex</p> <p>2001-01-01</p> <p>Studied the relationship between self-esteem and delinquency using latent growth curve <span class="hlt">modeling</span>. Analyses of panel data for 2,213 adolescent boys from the Youth in Transition Study supported Kaplan's self-derogation theory of delinquency (H. Kaplan, 1978) by showing that delinquency was positively associated with growth in self-esteem among</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JGRB..119.3646H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JGRB..119.3646H"><span id="translatedtitle">Band-limited topographic mass distribution generates full-spectrum gravity field: Gravity forward <span class="hlt">modeling</span> in the spectral and spatial domains <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hirt, Christian; Kuhn, Michael</p> <p>2014-04-01</p> <p>Most studies on gravity forward <span class="hlt">modeling</span> in the spectral domain truncate the gravitational potential spectra at a resolution commensurate with the input topographic mass <span class="hlt">model</span>. This implicitly assumes spectral consistency between topography and implied topographic potential. Here we demonstrate that a band-limited topographic mass distribution generates gravity signals with spectral energy at spatial scales far beyond the input topography's resolution. The spectral energy at scales shorter than the resolution of the input topography is associated with the contributions made by higher-order integer powers of the topography to the topographic potential. The pth integer power of a topography expanded to spherical harmonic degree n is found to make contributions to the topographic potential up to harmonic degree p times n. New numerical comparisons between Newton's integral evaluated in the spatial and spectral domain show that this previously little addressed truncation effect reaches amplitudes of several mGal for topography-implied gravity signals. <span class="hlt">Modeling</span> the short-scale gravity signal in the spectral domain improves the agreement between spatial and spectral domain techniques to the ?Gal level, or below 10-5 in terms of relative errors. Our findings have important implications for the use of gravity forward <span class="hlt">modeling</span> in geophysics and geodesy: The topographic potential in spherical harmonics must be calculated to a much higher harmonic degree than resolved by the input topography if consistency between topography and implied potential is sought. With the improved understanding of the spectral <span class="hlt">modeling</span> technique in this paper, theories, and computer implementations for both techniques can now be significantly better mutually validated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22351105','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22351105"><span id="translatedtitle">SU-E-T-284: <span class="hlt">Revisiting</span> Reference Dosimetry for the <span class="hlt">Model</span> S700 Axxent 50 KV{sub p} Electronic Brachytherapy Source</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Hiatt, JR; Rivard, MJ</p> <p>2014-06-01</p> <p>Purpose: The <span class="hlt">model</span> S700 Axxent electronic brachytherapy source by Xoft was characterized in 2006 by Rivard et al. The source design was modified in 2006 to include a plastic centering insert at the source tip to more accurately position the anode. The objectives of the current study were to establish an accurate Monte Carlo source <span class="hlt">model</span> for simulation purposes, to dosimetrically characterize the new source and obtain its TG-43 brachytherapy dosimetry parameters, and to determine dose differences between the source with and without the centering insert. Methods: Design information from dissected sources and vendor-supplied CAD drawings were used to devise the source <span class="hlt">model</span> for radiation transport simulations of dose distributions in a water phantom. Collision kerma was estimated as a function of radial distance, r, and polar angle, θ, for determination of reference TG-43 dosimetry parameters. Simulations were run for 10{sup 10} histories, resulting in statistical uncertainties on the transverse plane of 0.03% at r=1 cm and 0.08% at r=10 cm. Results: The dose rate distribution the transverse plane did not change beyond 2% between the 2006 <span class="hlt">model</span> and the current study. While differences exceeding 15% were observed near the source distal tip, these diminished to within 2% for r>1.5 cm. Differences exceeding a factor of two were observed near θ=150° and in contact with the source, but diminished to within 20% at r=10 cm. Conclusions: Changes in source design influenced the overall dose rate and distribution by more than 2% over a third of the available solid angle external from the source. For clinical applications using balloons or applicators with tissue located within 5 cm from the source, dose differences exceeding 2% were observed only for θ>110°. This study carefully examined the current source geometry and presents a modern reference TG-43 dosimetry dataset for the <span class="hlt">model</span> S700 source.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006JGRD..11114306S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006JGRD..11114306S"><span id="translatedtitle"><span class="hlt">Revisiting</span> China's CO emissions after the Transport and Chemical Evolution over the Pacific (TRACE-P) mission: Synthesis of inventories, atmospheric <span class="hlt">modeling</span>, and observations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Streets, David G.; Zhang, Qiang; Wang, Litao; He, Kebin; Hao, Jiming; Wu, Ye; Tang, Youhua; Carmichael, Gregory R.</p> <p>2006-07-01</p> <p>A new inventory of CO emissions in China is presented for the year 2001. This inventory improves and updates the a priori CO emission inventory prepared in support of NASA's TRACE-P mission in the spring of 2001. Analysis of CO observations using chemical transport <span class="hlt">models</span> in inverse and forward modes suggested that China's emissions were underestimated by about 50%. We have reexamined the source characteristics and conclude that emissions from cement kilns, brick kilns, and the iron and steel industry were underestimated. Our new estimate for China's CO emissions in 2001 is 157 Tg, 36% higher than the TRACE-P estimate for the year 2000 of 116 Tg. Bottom-up and <span class="hlt">modeled</span> emission estimates are now in good agreement, which represents a major success story for the TRACE-P mission. The new inventory has been gridded at 30 min 30 min resolution and tested with the CFORS/STEM-2K1 <span class="hlt">model</span>, considerably improving the correlation between <span class="hlt">model</span> predictions and observations (bias reduced from 27% to 9%). Propagation-of-error estimates in the new inventory yield an uncertainty of 68% (95% confidence intervals), lower than the TRACE-P value of 156%; however, the good agreement with results from inverse and forward <span class="hlt">models</span> implies a greater level of confidence than this. The largest remaining uncertainties concern (1) characterization of open vegetation burning, which cannot be resolved without new field studies; (2) emission factors for small combustion devices, for which emissions testing is urgently needed; and (3) residential fuel consumption, which may require a reassessment of China's official statistics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/16835884','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/16835884"><span id="translatedtitle">I-conotoxin superfamily <span class="hlt">revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Mondal, Sukanta; Babu, Rajasekaran Mohan; Bhavna, Rajasekaran; Ramakumar, Suryanarayanarao</p> <p>2006-11-01</p> <p>The I-conotoxin superfamily (I-Ctx) is known to have four disulfide bonds with the cysteine arrangement C-C-CC-CC-C-C, and the members inhibit or modify ion channels of nerve cells. Recently, Olivera and co-workers (FEBS J. 2005; 272: 4178-4188) have suggested that the previously described I-Ctx should now be divided into two different gene superfamilies, namely, I1 and I2, in view of their having two different types of signal peptides and exhibiting distinct functions. We have <span class="hlt">revisited</span> the 28 entries presently grouped as I-Ctx in UniProt Swiss-Prot knowledgebase, and on the basis of in silico analysis have divided them into I1 and I2 superfamilies. The sequence analysis has provided a framework for in silico annotation enabling us to carry out computer-based functional characterization of the UniProtKB/TrEMBL entry Q59AA4 from Conus miles and to predict it as a member of the I2 superfamily. Furthermore, we have predicted the mature toxin of this entry and have proposed that it may be an inhibitor of voltage-gated potassium channels. PMID:16835884</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009APS..DMP.Y1049W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009APS..DMP.Y1049W"><span id="translatedtitle">Double Photoionization of Lithium <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wehlitz, Ralf; Luki?, Dragan</p> <p>2009-05-01</p> <p>In a previous paperootnotetextR. Wehlitz, J.B. Bluett , and S.B. Whitfield, Phys. Rev. Lett. 89, 093002 (2002) we believed to have seen oscillations in the double-photoionization cross section of lithium. However, a recent investigation revealed that resonances at twice the photon energy (compared to the near-threshold energy region) are more pronounced than had been expectedootnotetextR. Wehlitz and P.N. Jurani'c, Phys. Rev. A 74, 042721 (2006). This prompted us to <span class="hlt">revisit</span> the near-threshold region of the lithium double-to-single photoionization ratio. Using a slightly higher energy resolution in a new experiment on the same beamline, we could identify resonances in that ratio due to second-order light. While the second-order light contribution is small, so is the double-photoionization cross section in first-order light near threshold. The ``resonances'' observed near threshold match the inner-shell resonances at twice the photon energy fairly well and can indeed explain the previously seen ``oscillations''.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015SCPMA..58j2001W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015SCPMA..58j2001W"><span id="translatedtitle">A short <span class="hlt">revisit</span> to Kuo-Brown effective interactions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, XiaoBao; Dong, GuoXiang</p> <p>2015-10-01</p> <p>This paper is a short <span class="hlt">revisit</span> to Kuo-Brown effective interaction derived from the Hamada-Johnston nucleon-nucleon potential, done by Gerry Brown and Tom Kuo. This effective interaction, derived in year 1966, is the first attempt to describe nuclear structure properties from the free nucleon-nucleon potential. Nowadays much progress has been achieved for the effective interactions in shell <span class="hlt">model</span>. We would compare the effective interactions obtained in the 1966 paper with up-to-date shell-<span class="hlt">model</span> interactions in sd-shell and pf-shell <span class="hlt">model</span> space. Recent knowledge of effective interactions on nuclear structure, can also be traced in the Kuo- Brown effective interaction, i.e., the universal roles of central and tensor forces, which reminds us that such discovery should be noticed much earlier.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Hail&pg=6&id=EJ462161','ERIC'); return false;" href="http://eric.ed.gov/?q=Hail&pg=6&id=EJ462161"><span id="translatedtitle">"Student Personnel: All Hail and Farewell!" <span class="hlt">Revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Bucci, Frank A.</p> <p>1993-01-01</p> <p><span class="hlt">Revisits</span> Crookston's (1976) article advocating to expunge term "student personnel," arguing that it is inappropriate and no longer descriptive of student affairs. Presents background of term to determine whether it continues to be used to identify chief student affairs officers and graduate programs that prepare sstudent affairs practitioners or</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Arendt&pg=2&id=EJ1018864','ERIC'); return false;" href="http://eric.ed.gov/?q=Arendt&pg=2&id=EJ1018864"><span id="translatedtitle">The Evil of Banality: Arendt <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Minnich, Elizabeth</p> <p>2014-01-01</p> <p>"The banality of evil" (Arendt) remains controversial and useful. Ironically, the concept is now itself a banality. To <span class="hlt">revisit</span> and extend it, we consider the "evil of banality", the profound dangers of cliched thoughtlessness. A distinction is proposed: "intensive" versus "extensive evils". The former takes</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=list+AND+resources+AND+called&pg=7&id=ED344225','ERIC'); return false;" href="http://eric.ed.gov/?q=list+AND+resources+AND+called&pg=7&id=ED344225"><span id="translatedtitle">Africa <span class="hlt">Revisited</span>. Impact II Dissemination Packet.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Smiling, Sandra</p> <p></p> <p>This paper briefly describes a unit of study or program called "Africa <span class="hlt">Revisited</span>," which gives students an opportunity to read African folktales and take part in making them come alive through sociodramatics, improvisations, puppetry, and creative writing. The paper's five main sections are as follows: (1) Project Overview; (2) Project Goals; (3)</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_21 --> <div id="page_22" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="421"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=led+AND+lights&pg=7&id=EJ949448','ERIC'); return false;" href="http://eric.ed.gov/?q=led+AND+lights&pg=7&id=EJ949448"><span id="translatedtitle"><span class="hlt">Revisiting</span> the Skills Agenda: A Complicated Geography</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Saunders, Angharad</p> <p>2011-01-01</p> <p>This paper <span class="hlt">revisits</span> the skills agenda and suggests that in light of shifts from supply-side to demand-led provision within the UK higher education sector, there is a need to think more critically about the role and place of skills within university curricula. It suggests that if universities are to respond effectively to sector changes, then the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=job+AND+performance+AND+personality&pg=4&id=EJ949448','ERIC'); return false;" href="http://eric.ed.gov/?q=job+AND+performance+AND+personality&pg=4&id=EJ949448"><span id="translatedtitle"><span class="hlt">Revisiting</span> the Skills Agenda: A Complicated Geography</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Saunders, Angharad</p> <p>2011-01-01</p> <p>This paper <span class="hlt">revisits</span> the skills agenda and suggests that in light of shifts from supply-side to demand-led provision within the UK higher education sector, there is a need to think more critically about the role and place of skills within university curricula. It suggests that if universities are to respond effectively to sector changes, then the…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/pages/biblio/1182470-phenomenology-oscillations-revisited','SCIGOV-DOEP'); return false;" href="http://www.osti.gov/pages/biblio/1182470-phenomenology-oscillations-revisited"><span id="translatedtitle">Phenomenology of n - n oscillations <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGESBeta</a></p> <p>Gardner, S.; Jafari, E.</p> <p>2015-05-22</p> <p>We <span class="hlt">revisit</span> the phenomenology of n-n oscillations in the presence of external magnetic fields, highlighting the role of spin. We show, contrary to long-held belief, that the n-n transition rate need not be suppressed, opening new opportunities for its empirical study.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=difference+AND+mentality&pg=2&id=EJ738721','ERIC'); return false;" href="http://eric.ed.gov/?q=difference+AND+mentality&pg=2&id=EJ738721"><span id="translatedtitle"><span class="hlt">Revisiting</span> the Regenerative Possibilities of Ortiz</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Duques, Matthew</p> <p>2004-01-01</p> <p>The author of this article <span class="hlt">revisits</span> Simon Ortiz's poem, "From Sand Creek," in which the latter can in so few words convey both the horrific tragedy of conquest and colonization, while at the same time find a space for possibility, a means for recovery that is never about forgetting but always occurs as a kind of recuperative remembering. Ortiz</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2259041','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2259041"><span id="translatedtitle">Silicon Uptake in Diatoms <span class="hlt">Revisited</span>: A <span class="hlt">Model</span> for Saturable and Nonsaturable Uptake Kinetics and the Role of Silicon Transporters1[OA</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Thamatrakoln, Kimberlee; Hildebrand, Mark</p> <p>2008-01-01</p> <p>The silicic acid uptake kinetics of diatoms were studied to provide a mechanistic explanation for previous work demonstrating both nonsaturable and Michaelis-Menten-type saturable uptake. Using 68Ge(OH)4 as a radiotracer for Si(OH)4, we showed a time-dependent transition from nonsaturable to saturable uptake kinetics in multiple diatom species. In cells grown under silicon (Si)-replete conditions, Si(OH)4 uptake was initially nonsaturable but became saturable over time. Cells prestarved for Si for 24 h exhibited immediate saturable kinetics. Data suggest nonsaturability was due to surge uptake when intracellular Si pool capacity was high, and saturability occurred when equilibrium was achieved between pool capacity and cell wall silica incorporation. In Thalassiosira pseudonana at low Si(OH)4 concentrations, uptake followed sigmoidal kinetics, indicating regulation by an allosteric mechanism. Competition of Si(OH)4 uptake with Ge(OH)4 suggested uptake at low Si(OH)4 concentrations was mediated by Si transporters. At high Si(OH)4, competition experiments and nonsaturability indicated uptake was not carrier mediated and occurred by diffusion. Zinc did not appear to be directly involved in Si(OH)4 uptake, in contrast to a previous suggestion. A <span class="hlt">model</span> for Si(OH)4 uptake in diatoms is presented that proposes two control mechanisms: active transport by Si transporters at low Si(OH)4 and diffusional transport controlled by the capacity of intracellular pools in relation to cell wall silica incorporation at high Si(OH)4. The <span class="hlt">model</span> integrates kinetic and equilibrium components of diatom Si(OH)4 uptake and consistently explains results in this and previous investigations. PMID:18162598</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JSG....69..519A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JSG....69..519A"><span id="translatedtitle"><span class="hlt">Revisiting</span> the Hubbert-Rubey pore pressure <span class="hlt">model</span> for overthrust faulting: Inferences from bedding-parallel detachment surfaces within Middle Devonian gas shale, the Appalachian Basin, USA</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Aydin, Murat G.; Engelder, Terry</p> <p>2014-12-01</p> <p>Both bedding-parallel slickensides and cleavage duplexes are forms of mesoscopic-scale detachment faulting populating black (Marcellus and Geneseo/Burket) and intervening gray (Mahantango) shales of the Middle Devonian, a section known for abnormal pore pressure below the Appalachian Plateau. The abundance and the orientation of slickensides and cleavage duplexes in the more organic-rich black shale relative to gray shale suggests that maturation-related abnormal pore pressure facilitates detachment, a mesoscopic manifestation of the Hubbert-Rubey pore pressure <span class="hlt">model</span> for overthrust faulting. The former are discrete slip surfaces whereas the latter consists of nested, anastomosing slip surfaces, either cutting through bedding or on disrupted bedding surfaces stacked as mesoscopic versions of thrust duplexes. Cleavage duplexes are between a few cm and over 1 m thick with their hanging walls commonly transported toward the Appalachian foreland, regardless of local limb dip. Cleavage duplexes are most common near the stratigraphic maximum flooding surface, the organic-rich section most prone to develop maturation-related pore pressure in the Middle Devonian gas shales. Bedding-parallel slickensides are somewhat more evenly distributed in the black shale but also found in overlying gray shale. In both black and gray shales, slickensides are more abundant on the limbs of folds, an indication of pore-pressure-related flexural-slip folding. On the macroscopic scale, the Pine Mountain Block of the Southern Appalachian Mountains was enabled by a basal detachment cutting along the Upper Devonian Chattanooga black shale which has a thermal maturity sufficient for the generation of abnormal pore pressure. The Pine Mountain block is a large-scale overthrust showing little evidence of collapse of the hinterland side, a credible example of a pore-pressure-aided overthrust fault block of the type envisioned by the Hubbert-Rubey <span class="hlt">model</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/21546354','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/21546354"><span id="translatedtitle"><span class="hlt">Revisiting</span> the yeast PPR proteins--application of an Iterative Hidden Markov <span class="hlt">Model</span> algorithm reveals new members of the rapidly evolving family.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lipinski, Kamil A; Puchta, Olga; Surendranath, Vineeth; Kudla, Marek; Golik, Pawel</p> <p>2011-10-01</p> <p>Pentatricopeptide repeat (PPR) proteins are the largest known RNA-binding protein family, and are found in all eukaryotes, being particularly abundant in higher plants. PPR proteins localize mostly to mitochondria and chloroplasts, and many were shown to modulate organellar genome expression on the posttranscriptional level. Although the genomes of land plants encode hundreds of PPR proteins, only a few have been identified in Fungi and Metazoa. As the current PPR motif profiles are built mainly on the basis of the predominant plant sequences, they are unlikely to be optimal for detecting fungal and animal members of the family, and many putative PPR proteins in these genomes may remain undetected. In order to verify this hypothesis, we designed a hidden Markov <span class="hlt">model</span>-based bioinformatic tool called Supervised Clustering-based Iterative Phylogenetic Hidden Markov <span class="hlt">Model</span> algorithm for the Evaluation of tandem Repeat motif families (SCIPHER) using sequence data from orthologous clusters from available yeast genomes. This approach allowed us to assign 12 new proteins in Saccharomyces cerevisiae to the PPR family. Similarly, in other yeast species, we obtained a 5-fold increase in the detection of PPR motifs, compared with the previous tools. All the newly identified S. cerevisiae PPR proteins localize in the mitochondrion and are a part of the RNA processing interaction network. Furthermore, the yeast PPR proteins seem to undergo an accelerated divergent evolution. Analysis of single and double amino acid substitutions in the Dmr1 protein of S. cerevisiae suggests that cooperative interactions between motifs and pseudoreversion could be the force driving this rapid evolution. PMID:21546354</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhDT.......189S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhDT.......189S"><span id="translatedtitle">Machining as a mechanical property test <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Smith, David L.</p> <p></p> <p>There is much need for data on mechanical behavior of metals at high strains and strain rates. This need is dictated by <span class="hlt">modeling</span> of processes like forming and machining, wherein the material in the deformation zone is subjected to severe deformation conditions atypical of conventional material property tests such as tension and torsion. Accurate flow stress data is an essential input for robust prediction of process outputs. Similar requirements arise from applications in high speed ballistic penetration and design of materials for armor. Since the deformation zone in cutting of metals is characterized by unique and extreme combinations of strain, strain rate and temperature, an opportunity exists for using plane-strain cutting as a mechanical property test for measuring flow properties of metals. The feasibility of using plane-strain cutting to measure flow properties of metals is <span class="hlt">revisited</span> in the light of recent data showing controllability of the deformation conditions in chip formation by systematic variation of process input parameters. A method is outlined as to how the deformation conditions can be varied by changing the process parameters. The method is applied to cutting of commercially pure copper (FCC), iron (BCC) and zinc (HCP). Forces and chip geometries are measured, in conjunction with particle image velocimetry characterization of the deformation using high speed image sequences. The flow stresses are estimated from these measurements. The measured flow stress and its dependence on strain are shown to agree well with prior measurements of these parameters using conventional tests, and flow stress inferred from hardness characterization. The method is also demonstrated to be able to measure properties of metals that recrystallize at room temperature (zinc), wherein quasi-static tests predict much lower strength. Sources of variability and uncertainty in the application of this measurement technique are discussed. Future work in the context of further evaluation of this measurement approach is proposed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..1712617M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..1712617M"><span id="translatedtitle">Configuration of geological domains and geodynamic evolution of the Africa-Eurasia plate boundary off SW Iberia <span class="hlt">revisited</span> based on seismic velocity and density <span class="hlt">models</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Martínez-Loriente, Sara; Sallarès, Valentí; Gràcia, Eulàlia; Bartolome, Rafael; Ranero, César</p> <p>2015-04-01</p> <p>We present a new classification of geological (basement) domains at the Africa-Eurasia plate boundary offshore SW Iberia, together with a regional geodynamic reconstruction spanning from the Mesozoic extension to the Neogene-to-present-day convergence. It is based on seismic velocity and density <span class="hlt">models</span> along two regional wide-angle seismic transects, one running NW-SE from the Tagus to the Seine abyssal plains, and the other running N-S from S Portugal to the Seine Abyssal Plain, combined with previously available information. The seismic velocity and density structure at the Seine Abyssal Plain and the internal Gulf of Cadiz indicates the presence of a highly heterogeneous oceanic crust, similar to that described in ultra-slow spreading centers, whereas in the Horseshoe and Tagus abyssal plains, the basement structure resembles that of exhumed mantle sections identified in the Northern Atlantic margin. The integration of all this new information allows defining the presence of three oceanic domains off SW Iberia: (1) the Seine Abyssal Plain domain, generated during the first stages of slow seafloor spreading in the NE segment of the Central Atlantic (Early Jurassic); (2) the Gulf of Cadiz domain, made of oceanic crust generated in the Alpine-Tethys spreading system between Iberia and Africa, which was coeval with the formation of the Seine Abyssal Plain domain and lasted up to the North Atlantic continental break-up (Late Jurassic); and (3) the Gorringe Bank domain, mainly made of rocks exhumed from the mantle with little synchronous magmatism, which formed during the first stages of North Atlantic opening (Early Cretaceous). Our <span class="hlt">models</span> suggest that the Seine Abyssal Plain and Gulf of Cadiz domains are separated by the Lineament South strike-slip fault, whereas the Gulf of Cadiz and Gorringe Bank domains appear to be limited by a deep thrust fault located at the center of the Horseshoe Abyssal Plain, which coincides with the seismicity cluster nucleated in the middle of the plain that shows moment tensor solutions of reverse faulting at depths of 40-60 km. The formation and evolution of these three domains during the Mesozoic is key to understand the sequence of events that occurred during the first stages of opening of the Northern Atlantic and its connection and interplay with the Western Mediterranean basin.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3152302','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3152302"><span id="translatedtitle">Mouse <span class="hlt">models</span> to assess the efficacy of non-typhoidal Salmonella vaccines: <span class="hlt">revisiting</span> the role of host innate susceptibility and routes of challenge</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Simon, Raphael; Tennant, Sharon M.; Galen, James E.; Levine, Myron M.</p> <p>2011-01-01</p> <p>Non-typhoidal Salmonella enterica (NTS) serovars Typhimurium and Enteritidis are important causes of bacterial gastroenteritis in the USA and worldwide. In sub-Saharan Africa these two serovars are emerging as agents associated with lethal invasive disease (e.g., bacteremia, meningitis). The development of NTS vaccines, based on mucosally-administered live attenuated strains and parenteral non-living antigens, could diminish the NTS disease burden globally. Mouse <span class="hlt">models</span> of S. Typhimurium and S. Enteritidis invasive disease can accelerate the development of NTS vaccines. Live attenuated NTS vaccines elicit both cellular and humoral immunity in mice and their efficacy is well established. In contrast, non-living vaccines that primarily elicit humoral immunity have demonstrated variable efficacy. An analysis of the reported studies with non-living vaccines against S. Typhimurium and S. Enteritidis reveals that efficacy is influenced by two important independent variables: 1) the innate susceptibility to NTS infection that differs dramatically between commonly used mouse strains and, 2) the virulence of the NTS strain used for challenge. Protection by non-living vaccines has generally been seen only in host-pathogen interactions where a sub-lethal infection results, such as challenging resistant mice with either highly virulent or weakly virulent strains or susceptible mice with weakly virulent strains. The immunologic basis of this discrepancy and the implications for human NTS vaccine development are reviewed herein. PMID:21616112</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2001SurSc.495..107W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2001SurSc.495..107W"><span id="translatedtitle">The three-step <span class="hlt">model</span> in electron spectroscopy <span class="hlt">revisited</span> I. Angular distribution of Auger electron emission from non-crystalline Al, Si and Cu surfaces</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Werner, Wolfgang S. M.; Tratnik, Herbert; Brenner, Josef; Stri, Herbert</p> <p>2001-12-01</p> <p>Measurements are presented of the Auger electron intensity emitted from non-crystalline Al, Si and Cu samples as a function of the emission angle, for a constant angle of incidence of the primary electrons. For this particular geometry, all features in the experimental angular distribution are completely attributable to the processes playing a role in the electron escape. It is found that surface roughness and electron refraction at the potential barrier do not affect the shape of the angular distribution. The angular distribution of the high energy core lines (CCC) are perfectly described by a cosine distribution. A distinct deviation of this behaviour is observed for the low energy valence band (CVV) transitions that is caused by the influence of surface excitations. Analysis of reflection electron energy loss spectra (REELS) demonstrates that for energies?1000 eV, the increase of surface excitations when going to more oblique emission angles is compensated by a decrease in the probability for bulk excitations. This complementarity of surface and bulk excitations is not perfect at lower energies and leads to a significant net effect of surface excitations. In particular, it is empirically found that the CVV angular distribution is consistent with the simple <span class="hlt">model</span> in which it is assumed that bulk inelastic collisions occur homogeneously throughout the semi-infinite solid.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JKPS...67.1755Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JKPS...67.1755Y"><span id="translatedtitle"><span class="hlt">Revisiting</span> the difference between traveling-wave and standing-wave thermoacoustic engines - A simple analytical <span class="hlt">model</span> for the standing-wave one</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yasui, Kyuichi; Kozuka, Teruyuki; Yasuoka, Masaki; Kato, Kazumi</p> <p>2015-11-01</p> <p>There are two major categories in a thermoacoustic prime-mover. One is the traveling-wave type and the other is the standing-wave type. A simple analytical <span class="hlt">model</span> of a standing-wave thermoacoustic prime-mover is proposed at relatively low heat-flux for a stack much shorter than the acoustic wavelength, which approximately describes the Brayton cycle. Numerical simulations of Rott's equations have revealed that the work flow (acoustic power) increases by increasing of the amplitude of the particle velocity (| U|) for the traveling-wave type and by increasing cos? for the standing-wave type, where ? is the phase difference between the particle velocity and the acoustic pressure. In other words, the standing-wave type is a phase-dominant type while the traveling-wave type is an amplitude-dominant one. The ratio of the absolute value of the traveling-wave component (| U|cos?) to that of the standing-wave component (| U|sin?) of any thermoacoustic engine roughly equals the ratio of the absolute value of the increasing rate of | U| to that of cos?. The different mechanism between the traveling-wave and the standing-wave type is discussed regarding the dependence of the energy efficiency on the acoustic impedance of a stack as well as that on ???, where ? is the angular frequency of an acoustic wave and ?? is the thermal relaxation time. While the energy efficiency of the traveling-wave type at the optimal ??? is much higher than that of the standing-wave type, the energy efficiency of the standing-wave type is higher than that of the traveling-wave type at much higher ??? under a fixed temperature difference between the cold and the hot ends of the stack.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1996styb.conf.....G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1996styb.conf.....G"><span id="translatedtitle">Statistical <span class="hlt">Models</span>, Yang-Baxter Equation and Related Topics - Proceedings of the Satellite MEeting of STATPHYS-19; Symmetry, Statistical, Mechanical <span class="hlt">Models</span> and Applications - Proceedings of the Seventh Nankai Workshop</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ge, M. L.; et al.</p> <p>1996-09-01</p> <p>The Table of Contents for the full book PDF is as follows: * Preface * Part I: Satellite Meeting of STATPHYS-19 * Boundary Yang-Baxter in the RSOS/SOS Representation * Quantum Domains in Ferromagnetic Anisotropic Heisenberg Chains * The Generalized Chiral Clock <span class="hlt">Model</span> and its Phase Diagram * Algebraic Solution of the Coincidence Problem for Crystals and Quasicrystals * Reflection Equations and Surface Critical Phenomena * Fully Packed Loop <span class="hlt">Models</span> * Quantum Field Theories in terms of Group-Valued Local Fields: An Overview * C-Statiscal Transition Transforms of the Heisenberg Spin Chain and Braided Symmetry * U(1)-Invariant Local and Integrable Lattice Formulation of the Massive Thirring <span class="hlt">Model</span> * Corner Transfer Matrices and Novel Polynomials * Rigorous and Numerical Results on Two-Dimensional Oriented Self-Avoiding Walks * The Price for Quantum Group Symmetry: Chiral Versus 2D WZNW <span class="hlt">Model</span> * Integrable Zn-Chiral Potts <span class="hlt">Model</span> : The Missing Rapidity-Momentum Relation * Dilute Algebras and Solvable Lattice <span class="hlt">Models</span> * Falicov-Kimball <span class="hlt">Model</span>: Ground States and Flux Phase Problem * Mutual Exclusion Statistics in the Exactly Solvable <span class="hlt">Model</span> of the Mott Metal-Insulator Transition * Quantum Group and the Hofstadter Problem * Domain Walls in the Spin-S Quantum Ising Chain * Quantization of Nonultralocal <span class="hlt">Models</span> - Generalization of the Theorem for the Multiple Coproduct * Multipoint Functions(Form-factors) of Quantum <span class="hlt">sine-Gordon</span> Field with Boundary * Three-Dimensional Vertex <span class="hlt">Model</span> * Probability of Phase Separation and Two Point Temperature Correlation Functions for the Bose Gas with Delta Interaction * On the Fundamental Invariant of the Hecke Algebra Hn(q) * Ternary Z3-Graded Algebras and New Gauge Theories * Thermodynamics of Integrable Quantum Chains : Free Energy and Correlation Lengths * Quantum Integrable Systems and Classical Discrete Nonlinear Dynamics * Quantum Jacobi-Trudi Formula and Analytic Bethe Ansatz * On Boundary Condition of Single Particle and the Spectrum of Many Particles * Hyperbolic Coxeter Group Invariants for Lattice Statistical Mechanics * Unitary Quantum Groups and Mutant Knots * Gauge <span class="hlt">Model</span> of QED and Unification of Statistical and Quantum Physics * The Method of Gauge Transformation in Random Spin Systems * Surface Free Energies and Surface Critical Behaviour of the ABF <span class="hlt">Models</span> with Fixed Boundaries * Stochastic Reaction-Diffusion Processes, Operator Algebras and Integrable Quantum Spin Chains * Vertex-Face Correspondence in Elliptic Solutions of the Yang-Baxter Equation * Logarithmic Anomalies of Susceptibility for Solvable <span class="hlt">Models</span> * Numerical Analysis on Topological Entanglements of Random Polygons * On Chiral Hubbard <span class="hlt">Model</span> at Strong Interaction * Soluble Free-Fermion <span class="hlt">Models</span> in d Dimensions * Bosonization Based on Bethe Ansatz Equations and Proof of the Conformal Conjecture * Fusion Hierarchies with Open Boundaries and Exactly Solvable <span class="hlt">Models</span> * Part II: The Seventh Nankai Workshop * Non-Minimal q-Deformations and Orthogonal Symmetries: uq(SO(5)) Example * Quantum Field Theory Under Hypertranscendental Action * Corner Transfer Matrix of Asymmetric Vertex <span class="hlt">Models</span> * Scaling Properties of the Ising <span class="hlt">Model</span> in a Field * One Dimensional Lattice <span class="hlt">Models</span> of Electrons with r-2 Hopping and Exchange * On the Phase Diagram of the q → 1 Extended Potts <span class="hlt">Model</span> and Lattice Animal Collapse * Solving Higher Simplex Equations Using Computer Algebra * Symmetry Group Invariants for Spontaneous Magnetization * Experimental Realizations of Integrable Reaction-Diffusion Processes in Biological and Chemical Systems * Zamolodchikov-Faddeev Algebra in 2-Component Anyons * Author Index</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ApJ...817L..18K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ApJ...817L..18K"><span id="translatedtitle"><span class="hlt">Revisiting</span> the Scattering Greenhouse Effect of CO2 Ice Clouds</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kitzmann, D.</p> <p>2016-02-01</p> <p>Carbon dioxide ice clouds are thought to play an important role for cold terrestrial planets with thick CO2 dominated atmospheres. Various previous studies showed that a scattering greenhouse effect by carbon dioxide ice clouds could result in a massive warming of the planetary surface. However, all of these studies only employed simplified two-stream radiative transfer schemes to describe the anisotropic scattering. Using accurate radiative transfer <span class="hlt">models</span> with a general discrete ordinate method, this study <span class="hlt">revisits</span> this important effect and shows that the positive climatic impact of carbon dioxide clouds was strongly overestimated in the past. The revised scattering greenhouse effect can have important implications for the early Mars, but also for planets like the early Earth or the position of the outer boundary of the habitable zone.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1081323','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1081323"><span id="translatedtitle"><span class="hlt">Revisiting</span> Johnson and Jackson boundary conditions for granular flows</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Li, Tingwen; Benyahia, Sofiane</p> <p>2012-07-01</p> <p>In this article, we <span class="hlt">revisit</span> Johnson and Jackson boundary conditions for granular flows. The oblique collision between a particle and a flat wall is analyzed by adopting the classic rigid-body theory and a more realistic semianalytical <span class="hlt">model</span>. Based on the kinetic granular theory, the input parameter for the partial-slip boundary conditions, specularity coefficient, which is not measurable in experiments, is then interpreted as a function of the particle-wall restitution coefficient, the frictional coefficient, and the normalized slip velocity at the wall. An analytical expression for the specularity coefficient is suggested for a flat, frictional surface with a low frictional coefficient. The procedure for determining the specularity coefficient for a more general problem is outlined, and a working approximation is provided.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013APS..DFDR34002D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013APS..DFDR34002D"><span id="translatedtitle">The flow along an external corner <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Denier, Jim; Jewell, Nathaniel</p> <p>2013-11-01</p> <p>We <span class="hlt">revisit</span> the problem of the flow of an almost inviscid fluid along an external corner made from the junction of two quarter infinite plates joined at an angle 0 < ? < ? / 2 . The structure of the boundary layer which develops along the corner is explored using a computational approach based upon a spectral element discretisation of the steady two-dimensional boundary-layer equations. We pay particular attention to the case when the angle ? is small, thus approximating the semi-infinte quarter plate problem considered by Stewartson (1961) and recently <span class="hlt">revisited</span> by Duck & Hewitt (2012). Our results, which demonstrate a thickening of the boundary-layer near the sharp corner, will be discussed in the context of the asymptotic theory developed in the aforementioned papers.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014APS..DNP.KE001G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014APS..DNP.KE001G"><span id="translatedtitle">Phenomenology of Neutron-Antineutron Oscillations <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gardner, Susan; Jafari, Ehsan</p> <p>2014-09-01</p> <p>We <span class="hlt">revisit</span> the phenomenology of neutron-antineutron (n- n) oscillations in the presence of external magnetic fields, highlighting the role of spin. We show, contrary to long-held belief, that the n- n transition rate can be enhanced under special conditions, opening new pathways for its empirical study. We <span class="hlt">revisit</span> the phenomenology of neutron-antineutron (n- n) oscillations in the presence of external magnetic fields, highlighting the role of spin. We show, contrary to long-held belief, that the n- n transition rate can be enhanced under special conditions, opening new pathways for its empirical study. Supported in part by the U.S. Department of Energy Office of Nuclear Physics under grant DE-FG02-96ER40989.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/12645611','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/12645611"><span id="translatedtitle"><span class="hlt">Revisiting</span> the definition of homo sapiens.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Loike, John D; Tendler, Moshe D</p> <p>2002-12-01</p> <p>Research in genomics, human cloning, and transgenic technology has challenged bioethicists and scientists to rethink the definition of human beings as a species. For example, should the definition incorporate a genetic criterion and how does the capacity to genetically engineer human beings affect the definition of our species? In considering these contemporary bioethical dilemmas, we <span class="hlt">revisit</span> an ancient source, the Talmud, and highlight how it provides specific biological, cultural, and genetic criteria to define the human species. PMID:12645611</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JHEP...06..002H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JHEP...06..002H"><span id="translatedtitle">On deformations of AdS n × S n supercosets</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hoare, B.; Roiban, R.; Tseytlin, A. A.</p> <p>2014-06-01</p> <p>We study the deformed AdS 5 × S 5 supercoset <span class="hlt">model</span> of arXiv:1309.5850 which depends on one parameter κ and has classical quantum group symmetry. We confirm the conjecture that in the "maximal" deformation limit, κ → ∞, this <span class="hlt">model</span> is T-dual to "flipped" double Wick rotation of the target space AdS 5 × S 5, i.e. dS 5 × H 5 space supported by an imaginary 5-form flux. In the imaginary deformation limit, κ → i, the corresponding target space metric is of a pp-wave type and thus the resulting light-cone gauge S-matrix becomes relativistically invariant. Omitting non-unitary contributions of imaginary WZ terms, we find that this tree-level S-matrix is equivalent to that of the generalized <span class="hlt">sine-Gordon</span> <span class="hlt">model</span> representing the Pohlmeyer reduction of the undeformed AdS 5 × S 5 superstring <span class="hlt">model</span>. We also study in some detail similar deformations of the AdS 3 × S 3 and AdS 2 × S 2 supercosets. The bosonic part of the deformed AdS 3 × S 3 <span class="hlt">model</span> happens to be equivalent to the symmetric case of the sum of the Fateev integrable deformation of the SL(2) and SU(2) principal chiral <span class="hlt">models</span>, while in the AdS 2 × S 2 case the role of the Fateev <span class="hlt">model</span> is played by the 2d "sausage" <span class="hlt">model</span>. The κ = i limits are again directly related to the Pohlmeyer reductions of the corresponding AdS n × S n supercosets: (2,2) super <span class="hlt">sine-Gordon</span> <span class="hlt">model</span> and its complex <span class="hlt">sine-Gordon</span> analog. We also discuss possible deformations of AdS 3 × S 3 with more than one parameter.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012PhRvD..85l3508M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012PhRvD..85l3508M"><span id="translatedtitle"><span class="hlt">Revisiting</span> cosmic no-hair theorem for inflationary settings</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Maleknejad, A.; Sheikh-Jabbari, M. M.</p> <p>2012-06-01</p> <p>In this work we <span class="hlt">revisit</span> Wald’s cosmic no-hair theorem [R. M. Wald, Phys. Rev. DPRVDAQ0556-2821 28, 2118 (1983).10.1103/PhysRevD.28.2118] in the context of accelerating Bianchi cosmologies for a generic cosmic fluid with nonvanishing anisotropic stress tensor and when the fluid energy-momentum tensor is of the form of a cosmological constant term plus a piece which does not respect strong or dominant energy conditions. Such a fluid is the one appearing in inflationary <span class="hlt">models</span>. We show that for such a system anisotropy may grow, in contrast to the cosmic no-hair conjecture. In particular, for a generic inflationary <span class="hlt">model</span> we show that there is an upper bound on the growth of anisotropy. For slow-roll inflationary <span class="hlt">models</span>, our analysis can be refined further and the upper bound is found to be of the order of slow-roll parameters. We examine our general discussions and our extension of Wald’s theorem for three classes of slow-roll inflationary <span class="hlt">models</span>, generic multiscalar field driven <span class="hlt">models</span>, anisotropic <span class="hlt">models</span> involving U(1) gauge fields and the gauge-flation scenario.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_22 --> <div id="page_23" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="441"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhRvA..93a1601B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhRvA..93a1601B"><span id="translatedtitle">Mott transition for strongly interacting one-dimensional bosons in a shallow periodic potential</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Boris, G.; Gori, L.; Hoogerland, M. D.; Kumar, A.; Lucioni, E.; Tanzi, L.; Inguscio, M.; Giamarchi, T.; D'Errico, C.; Carleo, G.; Modugno, G.; Sanchez-Palencia, L.</p> <p>2016-01-01</p> <p>We investigate the superfluid-insulator transition of one-dimensional interacting bosons in both deep and shallow periodic potentials. We compare a theoretical analysis based on quantum Monte Carlo simulations in continuum space and Luttinger liquid approach with experiments on ultracold atoms with tunable interactions and optical lattice depth. Experiments and theory are in excellent agreement. Our study provides a quantitative determination of the critical parameters for the Mott transition and defines the regimes of validity of widely used approximate <span class="hlt">models</span>, namely, the Bose-Hubbard and <span class="hlt">sine-Gordon</span> <span class="hlt">models</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2000PhLB..478..365B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2000PhLB..478..365B"><span id="translatedtitle">Extended complex trigonometry in relation to integrable /2d-quantum field theories and duality</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Baseilhac, P.; Galice, S.; Grangé, P.; Rausch de Traubenberg, M.</p> <p>2000-04-01</p> <p>Multicomplex numbers of order n have an associated trigonometry (multisine functions with /n-1 parameters) leading to a natural extension of the <span class="hlt">sine-Gordon</span> <span class="hlt">model</span>. The parameters are constrained from the requirement of local current conservation. In two dimensions for /n<6 known integrable <span class="hlt">models</span> (deformed Toda and non-linear sigma, pure affine Toda...) with dual counterparts are obtained in this way from the multicomplex space MCn itself and from the natural embedding MCn⊂MCm,n<m. For /n>=6 a generic constraint on the space of parameters is obtained from current conservation at first order in the interaction Lagrangian.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhRvB..92d5435V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhRvB..92d5435V"><span id="translatedtitle">One-dimensional Josephson junction arrays: Lifting the Coulomb blockade by depinning</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vogt, Nicolas; Schäfer, Roland; Rotzinger, Hannes; Cui, Wanyin; Fiebig, Andreas; Shnirman, Alexander; Ustinov, Alexey V.</p> <p>2015-07-01</p> <p>Experiments with one-dimensional arrays of Josephson junctions in the regime of dominating charging energy show that the Coulomb blockade is lifted at the threshold voltage, which is proportional to the array's length and depends strongly on the Josephson energy. We explain this behavior as depinning of the Cooper-pair-charge-density by the applied voltage. We assume strong charge disorder and argue that physics around the depinning point is governed by a disordered <span class="hlt">sine-Gordon</span>-like <span class="hlt">model</span>. This allows us to employ the well-known theory of charge density wave depinning. Our <span class="hlt">model</span> is in good agreement with the experimental data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1044922','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1044922"><span id="translatedtitle">Sloan Digital Sky Survey Photometric Calibration <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Marriner, John; /Fermilab</p> <p>2012-06-29</p> <p>The Sloan Digital Sky Survey calibration is <span class="hlt">revisited</span> to obtain the most accurate photometric calibration. A small but significant error is found in the flat-fielding of the Photometric telescope used for calibration. Two SDSS star catalogs are compared and the average difference in magnitude as a function of right ascension and declination exhibits small systematic errors in relative calibration. The photometric transformation from the SDSS Photometric Telescope to the 2.5 m telescope is recomputed and compared to synthetic magnitudes computed from measured filter bandpasses.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EPJC...74.3069L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EPJC...74.3069L"><span id="translatedtitle"><span class="hlt">Revisiting</span> Gribov's copies inside the horizon</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Landim, R. R.; Lemes, V. E. R.; Ventura, O. S.; Vilar, L. C. Q.</p> <p>2014-11-01</p> <p>In this work, we <span class="hlt">revisit</span> the problem of legitimate topologically trivial Gribov copies inside the Gribov horizon. We avoid the reducibility problem which hampered the standard construction of van Baal, and then we are able to build a valid example with spherical symmetry. We also apply the same technique in the presence of a background of a Polyakov instanton in a Euclidian 3D spacetime, in order to study the effect of a non-trivial environment in the generation of multiple copies inside the horizon.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004OLEB...34..361O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004OLEB...34..361O"><span id="translatedtitle">Prebiotic Adenine <span class="hlt">Revisited</span>: Eutectics and Photochemistry</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Orgel, Leslie E.</p> <p>2004-08-01</p> <p>Recent studies support an earlier suggestion that, if adenine was formed prebiotically on the primitive earth, eutectic freezing of hydrogen cyanide solutions is likely to have been important. Here we <span class="hlt">revisit</span> the suggestion that the synthesis of adenine may have involved the photochemical conversion of the tetramer of hydrogen cyanide in eutectic solution to 4-amino-5-cyano-imidazole. This would make possible a reaction sequence that does not require the presence of free ammonia. It is further suggested that the reaction of cyanoacetylene with cyanate in eutectic solution to give cytosine might have proceeded in parallel with adenine synthesis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012PhRvD..86a3001A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012PhRvD..86a3001A"><span id="translatedtitle"><span class="hlt">Revisiting</span> the naturalness problem: Who is afraid of quadratic divergences?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Aoki, Hajime; Iso, Satoshi</p> <p>2012-07-01</p> <p>It is widely believed that quadratic divergences severely restrict natural constructions of particle physics <span class="hlt">models</span> beyond the standard <span class="hlt">model</span> (SM). Supersymmetry provides a beautiful solution, but the recent LHC experiments have excluded large parameter regions of supersymmetric extensions of the SM. It will now be important to reconsider whether we have been misinterpreting the quadratic divergences in field theories. In this paper, we <span class="hlt">revisit</span> the problem from the viewpoint of the Wilsonian renormalization group and argue that quadratic divergences—which can always be absorbed into a position of the critical surface—should be simply subtracted in <span class="hlt">model</span> constructions. Such a picture gives another justification to the argument [W. A. Bardeen, Report No. FERMILAB-CONF-95-391-T] that the scale invariance of the SM, except for the soft-breaking terms, is an alternative solution to the naturalness problem. It also largely broadens possibilities of <span class="hlt">model</span> constructions beyond the SM since we just need to take care of logarithmic divergences, which cause mixings of various physical scales and runnings of couplings.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/5264913','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/5264913"><span id="translatedtitle">Quasiperiodic and chaotic behavior due to competition between spatial and temporal modes in long Josephson junctions</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Guerrero, L.E.; Octavio, M.</p> <p>1988-05-01</p> <p>We present numerical simulations of long Josephson junctions in the presence of an rf bias and an applied magnetic field, which we <span class="hlt">model</span> with a <span class="hlt">sine-Gordon</span>-like equation. We focus our attention on quasiperiodic and chaotic dynamics and their transitions. We show that quasiperiodicity arises from the competition between two incommensurate frequencies: one due to the success of the system in exciting a solitonlike structure and the second one due to the rf drive. We demonstrate the universality of the multifractal structure of the attractor at the onset of chaos.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/19257092','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/19257092"><span id="translatedtitle">Solitonlike base pair opening in a helicoidal DNA: an analogy with a helimagnet and a cholesteric liquid crystal.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Daniel, M; Vasumathi, V</p> <p>2009-01-01</p> <p>We propose a <span class="hlt">model</span> for DNA dynamics by introducing the helical structure through twist deformation in analogy with the structure of a helimagnet and a cholesteric liquid-crystal system. The dynamics in this case is found to be governed by the completely integrable <span class="hlt">sine</span> <span class="hlt">Gordon</span> equation, which admits kink-antikink solitons with increased width, representing a wide base-pair opening configuration in DNA. The results show that the helicity introduces a length-scale variation and thus provides a better representation of the base-pair opening in DNA. PMID:19257092</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005cdtc.book..189S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005cdtc.book..189S"><span id="translatedtitle">Energy Surfaces and Hierarchies of Bifurcations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shlizerman, Eli; Rom-Kedar, Vered</p> <p></p> <p>A two-degrees of freedom near integrable Hamiltonian which arises in the study of low-amplitude near-resonance envelope solutions of the forced <span class="hlt">Sine-Gordon</span> equation is analyzed. The energy momentum bifurcation diagrams and the Fomenko graphs are constructed and reveal the bifurcation values at which the lower dimensional <span class="hlt">model</span> exhibits instabilities and non-regular orbits of a new type. Furthermore, this study leads to some new insights regarding the hierarchy of bifurcations appearing in integrable Hamiltonian systems and the role of global bifurcations in the energy momentum bifurcation diagrams.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/6914652','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/6914652"><span id="translatedtitle">Phase transitions in dissipative Josephson chains</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Bobbert, P.A.; Fazio, R.; Schoen, G. ); Zimanyi, G.T. )</p> <p>1990-03-01</p> <p>We study the zero-temperature phase transitions of a chain of Josephson junctions, taking into account the quantum fluctuations due to the charging energy and the effects of an Ohmic dissipation. We map the problem onto a generalized Coulomb gas <span class="hlt">model</span>, which then is transformed into a <span class="hlt">sine-Gordon</span> field theory. Apart from the expected dipole unbinding transition, which describes a transition between globally superconducting and resistive behavior, we find a quadrupole unbinding transition at a critical strength of the dissipation. This transition separates two superconducting states characterized by different local properties.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25248184','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25248184"><span id="translatedtitle">Quantization table design <span class="hlt">revisited</span> for image/video coding.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Yang, En-Hui; Sun, Chang; Meng, Jin</p> <p>2014-11-01</p> <p>Quantization table design is <span class="hlt">revisited</span> for image/video coding where soft decision quantization (SDQ) is considered. Unlike conventional approaches, where quantization table design is bundled with a specific encoding method, we assume optimal SDQ encoding and design a quantization table for the purpose of reconstruction. Under this assumption, we <span class="hlt">model</span> transform coefficients across different frequencies as independently distributed random sources and apply the Shannon lower bound to approximate the rate distortion function of each source. We then show that a quantization table can be optimized in a way that the resulting distortion complies with certain behavior. Guided by this new design principle, we propose an efficient statistical-<span class="hlt">model</span>-based algorithm using the Laplacian <span class="hlt">model</span> to design quantization tables for DCT-based image coding. When applied to standard JPEG encoding, it provides more than 1.5-dB performance gain in PSNR, with almost no extra burden on complexity. Compared with the state-of-the-art JPEG quantization table optimizer, the proposed algorithm offers an average 0.5-dB gain in PSNR with computational complexity reduced by a factor of more than 2000 when SDQ is OFF, and a 0.2-dB performance gain or more with 85% of the complexity reduced when SDQ is ON. Significant compression performance improvement is also seen when the algorithm is applied to other image coding systems proposed in the literature. PMID:25248184</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.4032G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.4032G"><span id="translatedtitle">Silicate Glass Corrosion Mechanism <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Geisler, Thorsten; Lenting, Christoph; Dohmen, Lars</p> <p>2015-04-01</p> <p>Understanding the mechanism(s) of aqueous corrosion of nuclear waste borosilicate glasses is essential to predict their long-term aqueous durability in a geologic repository. Several observations have been made with compositionally different silicate glasses that cannot be explained by any of the established glass corrosion <span class="hlt">models</span>. These <span class="hlt">models</span> are based on diffusion-controlled ion exchange and subsequent structural reorganisation of a leached, hydrated residual glass, leaving behind a so-called gel layer. In fact, the common observation of lamellar to more complex pattern formation observed in experiment and nature, the porous structure of the corrosion layer, an atomically sharp boundary between the corrosion zone and the underlying pristine glass, as well as results of novel isotope tracer and in situ, real time experiments rather support an interface-coupled glass dissolution-silica reprecipitation <span class="hlt">model</span>. In this <span class="hlt">model</span>, the congruent dissolution of the glass is coupled in space and time to the precipitation and growth of amorphous silica at an inwardly moving reaction front. We suggest that these coupled processes have to be considered to realistically <span class="hlt">model</span> the long-term performance of silicate glasses in aqueous environments.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1416896','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1416896"><span id="translatedtitle">Malaria resurgence in the East African highlands: Temperature trends <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Pascual, M.; Ahumada, J. A.; Chaves, L. F.; Rod, X.; Bouma, M.</p> <p>2006-01-01</p> <p>The incidence of malaria in the East African highlands has increased since the end of the 1970s. The role of climate change in the exacerbation of the disease has been controversial, and the specific influence of rising temperature (warming) has been highly debated following a previous study reporting no evidence to support a trend in temperature. We <span class="hlt">revisit</span> this result using the same temperature data, now updated to the present from 1950 to 2002 for four high-altitude sites in East Africa where malaria has become a serious public health problem. With both nonparametric and parametric statistical analyses, we find evidence for a significant warming trend at all sites. To assess the biological significance of this trend, we drive a dynamical <span class="hlt">model</span> for the population dynamics of the mosquito vector with the temperature time series and the corresponding detrended versions. This approach suggests that the observed temperature changes would be significantly amplified by the mosquito population dynamics with a difference in the biological response at least 1 order of magnitude larger than that in the environmental variable. Our results emphasize the importance of considering not just the statistical significance of climate trends but also their biological implications with dynamical <span class="hlt">models</span>. PMID:16571662</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/23325556','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/23325556"><span id="translatedtitle">Search for identical octapeptides in unrelated proteins: Structural plasticity <span class="hlt">revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Saravanan, K M; Selvaraj, S</p> <p>2012-01-01</p> <p>Since proteins are dynamic in nature, they can alter their local structure in response to changes in their environment factors such as temperature, pH, phosphorylation, and binding of other small molecules. These conformational changes are extremely important for the correct folding and functioning of proteins. There are also a number of diseases associated with protein conformational change such as amyloid diseases. To stimulate research into the above factors which specify one conformation over another, different theoretical <span class="hlt">models</span> have been proposed and tested against sequence similar distant structure protein fragments. In order to simplify the computational complexity of identifying conformational changes in proteins, various local sequence search algorithms were employed and the structural plasticity in unrelated proteins was examined by various research groups. In the present work, we <span class="hlt">revisit</span> the mechanism of structural plasticity in unrelated proteins with increased number of structures in Protein Data Bank by comparing identical octapeptides in unrelated proteins with dictionary of protein secondary structure extracted from existing experimental data. Our goal is to bring out the influence of hydrophobic residues, hydrophilic residues, flanking residues, difference in secondary structural propensities of surrounding residues, difference in phi-psi angles and local and nonlocal interactions in identical octapeptides adopting different conformations. Also we have used surrounding hydrophobicity, environment dependent interaction energy, atomic mean force potential, structural unit contacts and difference profiles <span class="hlt">models</span> to explore the factors which cause structural plasticity. The results discussed here may provide insights into protein folding, design and function. PMID:23325556</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=CREST&pg=3&id=EJ195828','ERIC'); return false;" href="http://eric.ed.gov/?q=CREST&pg=3&id=EJ195828"><span id="translatedtitle">Counseling Delinquents: Dual Treatment <span class="hlt">Revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Lee, Robert; Haynes, Nancy M.</p> <p>1978-01-01</p> <p>The results of four studies conducted to measure the effectiveness of Clinical Rehabilitation Support Teams (Project CREST) are summarized. Professional counseling was provided to delinquent youths, as were regular probation services--a dual-treatment <span class="hlt">model</span>. Studies indicate that clients in the CREST program have consistently shown decreased</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=honesty&pg=5&id=EJ830530','ERIC'); return false;" href="http://eric.ed.gov/?q=honesty&pg=5&id=EJ830530"><span id="translatedtitle">The Medical Excuse Game <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Corson-Rikert, Janet; Christmas, William A.</p> <p>2009-01-01</p> <p>Academic policies that require medical excuses are based on mistrust of students and conflict with institutional honor codes. Such policies undermine the philosophical and educational foundations of higher education; namely, to <span class="hlt">model</span> and nurture honesty, integrity, and citizenship in emerging adults. Instead, they encourage hypocrisy and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=goldberger&pg=6&id=EJ290540','ERIC'); return false;" href="http://eric.ed.gov/?q=goldberger&pg=6&id=EJ290540"><span id="translatedtitle">Public and Private Schools <span class="hlt">Revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Cain, Glen G.; Goldberger, Arthur S.</p> <p>1983-01-01</p> <p>The authors recap the main issues in their critique of Coleman, Hoffer, and Kilgore (CHK) as well as CHK's rejoinder. These issues include reliability and validity of test scores, the use of particular statistical <span class="hlt">models</span> and inferences from these, and the importance of school policies in assuring higher achievement among students. (IS)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/21668217','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/21668217"><span id="translatedtitle">Long, cold, early r process? Neutrino-induced nucleosynthesis in He shells <span class="hlt">revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Banerjee, Projjwal; Haxton, W C; Qian, Yong-Zhong</p> <p>2011-05-20</p> <p>We <span class="hlt">revisit</span> a ν-driven r-process mechanism in the He shell of a core-collapse supernova, finding that it could succeed in early stars of metallicity Z ≲ 10⁻³ Z(⊙), at relatively low temperatures and neutron densities, producing A ~ 130 and 195 abundance peaks over ~10-20 s. The mechanism is sensitive to the ν emission <span class="hlt">model</span> and to ν oscillations. We discuss the implications of an r process that could alter interpretations of abundance data from metal-poor stars, and point out the need for further calculations that include effects of the supernova shock. PMID:21668217</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016MNRAS.455.4512R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016MNRAS.455.4512R"><span id="translatedtitle">Slowly rotating homogeneous masses <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Reina, Borja</p> <p>2016-02-01</p> <p>Hartle's <span class="hlt">model</span> for slowly rotating stars has been extensively used to compute equilibrium configurations of slowly rotating stars to second order in perturbation theory in general relativity, given a barotropic equation of state. A recent study based on the modern theory of perturbed matchings concludes that the functions in the (first and second order) perturbation tensors can always be taken as continuous at the surface of the star, except for the second-order function m0. This function presents a jump at the surface of the star proportional to the discontinuity of the energy density there. This concerns only a particular outcome of the <span class="hlt">model</span>: the change in mass ?M. In this paper, the amended change in mass is calculated for the case of constant density stars.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_23 --> <div id="page_24" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="461"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21503583','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21503583"><span id="translatedtitle"><span class="hlt">Revisit</span> of cosmic age problem</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Wang Shuang; Li Xiaodong; Li Miao</p> <p>2010-11-15</p> <p>We investigate the cosmic age problem associated with 9 extremely old globular clusters in M31 galaxy and 1 very old high-z quasar automatic plate-measuring machine 08279+5255 at z=3.91. These 9 globular clusters have not been used to study the cosmic age problem in the previous literature. By evaluating the age of the Universe in the {Lambda} cold dark matter <span class="hlt">model</span> with the observational constraints from the Type Ia supernovae, the baryon acoustic oscillations, the cosmic microwave background, and the independent H{sub 0} measurements, we find that the existence of 5 globular clusters and 1 high-z quasar are in tension (over 2{sigma} confidence level) with the current cosmological observations. So if the age estimates of these objects are correct, the cosmic age puzzle still remains in the standard cosmology. Moreover, we extend our investigations to the cases of the interacting dark energy <span class="hlt">models</span>. It is found that although the introduction of the interaction between dark sectors can give a larger cosmic age, the interacting dark energy <span class="hlt">models</span> still have difficulty to pass the cosmic age test.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2557748','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2557748"><span id="translatedtitle">Influenza A virus recycling <span class="hlt">revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Dowdle, W. R.</p> <p>1999-01-01</p> <p>Current textbooks link influenza pandemics to influenza A virus subtypes H2 (1889-91), H3 (1990), H1 (1918-20), H2 (1957-58) and H3 (1968), a pattern suggesting subtype recycling in humans. Since H1 reappeared in 1977, whatever its origin, some workers feel that H2 is the next pandemic candidate. This report reviews the publications on which the concept of influenza A virus subtype recycling is based and concludes that the data are inconsistent with the purported sequence of events. The three influenza pandemics prior to 1957-58 were linked with subtypes through retrospective studies of sera from the elderly, or through seroarchaeology. The pandemic seroarchaeological <span class="hlt">model</span> for subtype H1 has been validated by the recent recovery of swine virus RNA fragments from persons who died from influenza in 1918. Application of the <span class="hlt">model</span> to pre-existing H3 antibody among the elderly links the H3 subtype to the pandemic of 1889-91, not that of 1900 as popularly quoted. Application of the <span class="hlt">model</span> to pre-existing H2 antibody among the elderly fails to confirm that this subtype caused a pandemic in the late 1800's, a finding which is consistent with age-related excess mortality patterns during the pandemics of 1957 (H2) and 1968 (H3). H2 variants should be included in pandemic planning for a number of reasons, but not because of evidence of recycling. It is not known when the next pandemic will occur or which of the 15 (or more) haemagglutinin subtypes will be involved. Effective global surveillance remains the key to influenza preparedness. PMID:10593030</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4231082','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4231082"><span id="translatedtitle">Risk Prediction of Emergency Department <span class="hlt">Revisit</span> 30 Days Post Discharge: A Prospective Study</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Hao, Shiying; Jin, Bo; Shin, Andrew Young; Zhao, Yifan; Zhu, Chunqing; Li, Zhen; Hu, Zhongkai; Fu, Changlin; Ji, Jun; Wang, Yong; Zhao, Yingzhen; Dai, Dorothy; Culver, Devore S.; Alfreds, Shaun T.; Rogow, Todd; Stearns, Frank; Sylvester, Karl G.; Widen, Eric; Ling, Xuefeng B.</p> <p>2014-01-01</p> <p>Background Among patients who are discharged from the Emergency Department (ED), about 3% return within 30 days. <span class="hlt">Revisits</span> can be related to the nature of the disease, medical errors, and/or inadequate diagnoses and treatment during their initial ED visit. Identification of high-risk patient population can help device new strategies for improved ED care with reduced ED utilization. Methods and Findings A decision tree based <span class="hlt">model</span> with discriminant Electronic Medical Record (EMR) features was developed and validated, estimating patient ED 30 day <span class="hlt">revisit</span> risk. A retrospective cohort of 293,461 ED encounters from HealthInfoNet (HIN), Maine's Health Information Exchange (HIE), between January 1, 2012 and December 31, 2012, was assembled with the associated patients' demographic information and one-year clinical histories before the discharge date as the inputs. To validate, a prospective cohort of 193,886 encounters between January 1, 2013 and June 30, 2013 was constructed. The c-statistics for the retrospective and prospective predictions were 0.710 and 0.704 respectively. Clinical resource utilization, including ED use, was analyzed as a function of the ED risk score. Cluster analysis of high-risk patients identified discrete sub-populations with distinctive demographic, clinical and resource utilization patterns. Conclusions Our ED 30-day <span class="hlt">revisit</span> <span class="hlt">model</span> was prospectively validated on the Maine State HIN secure statewide data system. Future integration of our ED predictive analytics into the ED care work flow may lead to increased opportunities for targeted care intervention to reduce ED resource burden and overall healthcare expense, and improve outcomes. PMID:25393305</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19890043816&hterms=LTE+OFDMA&qs=Ntx%3Dmode%2Bmatchany%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DLTE%2BOFDMA','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19890043816&hterms=LTE+OFDMA&qs=Ntx%3Dmode%2Bmatchany%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DLTE%2BOFDMA"><span id="translatedtitle">Non-LTE CO, <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ayres, Thomas R.; Wiedemann, Gunter R.</p> <p>1989-01-01</p> <p>A more extensive and detailed non-LTE simulation of the Delta v = 1 bands of CO than attempted previously is reported. The equations of statistical equilibrium are formulated for a <span class="hlt">model</span> molecule containing 10 bound vibrational levels, each split into 121 rotational substates and connected by more than 1000 radiative transitions. Solutions are obtained for self-consistent populations and radiation fields by iterative application of the 'Lambda-operator' to an initial LTE distribution. The formalism is used to illustrate <span class="hlt">models</span> of the sun and Arcturus. For the sun, negligible departures from LTE are found in either a theoretical radiative-equilibrium photosphere with outwardly falling temperatures in its highest layers or in a semiempirical hot chromosphere that reproduces the spatially averaged emission cores of Ca II H and K. The simulations demonstrate that the puzzling 'cool cores' of the CO Delta V = 1 bands observed in limb spectra of the sun and in flux spectra of Arcturus cannot be explained simply by non-LTE scattering effects.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22373670','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22373670"><span id="translatedtitle">The isotropic radio background <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Fornengo, Nicolao; Regis, Marco; Lineros, Roberto A.</p> <p>2014-04-01</p> <p>We present an extensive analysis on the determination of the isotropic radio background. We consider six different radio maps, ranging from 22 MHz to 2.3 GHz and covering a large fraction of the sky. The large scale emission is <span class="hlt">modeled</span> as a linear combination of an isotropic component plus the Galactic synchrotron radiation and thermal bremsstrahlung. Point-like and extended sources are either masked or accounted for by means of a template. We find a robust estimate of the isotropic radio background, with limited scatter among different Galactic <span class="hlt">models</span>. The level of the isotropic background lies significantly above the contribution obtained by integrating the number counts of observed extragalactic sources. Since the isotropic component dominates at high latitudes, thus making the profile of the total emission flat, a Galactic origin for such excess appears unlikely. We conclude that, unless a systematic offset is present in the maps, and provided that our current understanding of the Galactic synchrotron emission is reasonable, extragalactic sources well below the current experimental threshold seem to account for the majority of the brightness of the extragalactic radio sky.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3099540','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3099540"><span id="translatedtitle"><span class="hlt">Revisiting</span> the Simplified Bernoulli Equation</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Heys, Jeffrey J; Holyoak, Nicole; Calleja, Anna M; Belohlavek, Marek; Chaliki, Hari P</p> <p>2010-01-01</p> <p>Background: The assessment of the severity of aortic valve stenosis is done by either invasive catheterization or non-invasive Doppler Echocardiography in conjunction with the simplified Bernoulli equation. The catheter measurement is generally considered more accurate, but the procedure is also more likely to have dangerous complications. Objective: The focus here is on examining computational fluid dynamics as an alternative method for analyzing the echo data and determining whether it can provide results similar to the catheter measurement. Methods: An in vitro heart <span class="hlt">model</span> with a rigid orifice is used as a first step in comparing echocardiographic data, which uses the simplified Bernoulli equation, catheterization, and echocardiographic data, which uses computational fluid dynamics (i.e., the Navier-Stokes equations). Results: For a 0.93cm2 orifice, the maximum pressure gradient predicted by either the simplified Bernoulli equation or computational fluid dynamics was not significantly different from the experimental catheter measurement (p > 0.01). For a smaller 0.52cm2 orifice, there was a small but significant difference (p < 0.01) between the simplified Bernoulli equation and the computational fluid dynamics simulation, with the computational fluid dynamics simulation giving better agreement with experimental data for some turbulence <span class="hlt">models</span>. Conclusion: For this simplified, in vitro system, the use of computational fluid dynamics provides an improvement over the simplified Bernoulli equation with the biggest improvement being seen at higher valvular stenosis levels. PMID:21625471</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015GeoRL..42.8758P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015GeoRL..42.8758P"><span id="translatedtitle"><span class="hlt">Revisiting</span> ice nucleation from precipitation samples</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Petters, M. D.; Wright, T. P.</p> <p>2015-10-01</p> <p>An emerging and unsolved question is the sensitivity of cloud processes, precipitation, and climate to the atmospheric ice nucleus spectrum. This work <span class="hlt">revisits</span> estimation of atmospheric ice-nucleating particle concentration derived from cloud water and precipitation samples representing a wide range of geographical locations, seasons, storm systems, precipitation types, instruments, concentrations, and temperatures. Concentrations of ice-nucleating particles are shown to vary over 10 orders of magnitude. High variability is observed in the -5C to -12C range which is suggested to be biologically derived nuclei whose life cycle is associated with intermittent source and efficient sink processes. The highest ever observed nucleus concentrations at -8C are 3 orders of magnitude lower than observed ice crystal concentrations in tropical cumuli at the same temperature. The observed upper and lower limits of the nucleus spectrum provide a possible constraint on minimum enhancement factors for secondary ice formation processes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22004263','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22004263"><span id="translatedtitle">ALFVEN WAVES IN SHEAR FLOWS <span class="hlt">REVISITED</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Hollweg, Joseph V.; Kaghashvili, Edisher Kh.</p> <p>2012-01-10</p> <p>We <span class="hlt">revisit</span> our earlier study of the evolution of an initial propagating Alfven wave in a magnetic-field-aligned flow with a cross-field velocity shear. Our goal is to show how the Alfven wave drives up plasma density fluctuations which might be observed and serve as a signature of the presence of Alfven waves in regions such as the solar corona which are inaccessible to direct observations. Here, we introduce a new initial condition which takes into account the initial distortion of the streamlines by the Alfven wave, and we present new analytical results for the driven waves. We find that the density fluctuations of a properly placed linearly polarized Alfven wave in a shear flow are much smaller than we originally estimated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21607926','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21607926"><span id="translatedtitle">Visser's massive graviton bimetric theory <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Roany, Alain de; Chauvineau, Bertrand; Freitas Pacheco, Jose A. de</p> <p>2011-10-15</p> <p>A massive gravity theory was proposed by Visser in the late 1990s. This theory, based on a background metric b{sub {alpha}{beta}} and on an usual dynamical metric g{sub {alpha}{beta}} has the advantage of being free of ghosts as well as discontinuities present in other massive theories proposed in the past. In the present investigation, the equations of Visser's theory are <span class="hlt">revisited</span> with particular care on the related conservation laws. It will be shown that a multiplicative factor is missing in the graviton tensor originally derived by Visser, which has no incidence on the weak field approach but becomes important in the strong field regime when, for instance, cosmological applications are considered. In this case, contrary to some previous claims found in the literature, we conclude that a nonstatic background metric is required in order to obtain a solution able to mimic the {Lambda}CDM cosmology.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/11144856','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/11144856"><span id="translatedtitle">L'enfant et les sortilges <span class="hlt">revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hindle, D</p> <p>2000-12-01</p> <p>The author discusses 'L'Enfant et les sortilges', an opera by Ravel based on a short story by Colette, which traces the trials and tribulations of a young boy whose bad behaviour leads to his being sent to his room, left alone and given only tea and bread until dinner. His progression from anger to persecution and fear, the various defences he employs to protect himself from feeling overwhelmed and his despair are graphically illustrated through words and music. The author considers the opera in relation to Klein's theory of the paranoidschizoid position and the struggle involved in maintaining contact with good objects, externally and internally. <span class="hlt">Revisiting</span> the opera in light of Meltzer's contribution to psychoanalytic thinking provides a wider perspective in which to explore what he has termed the aesthetic conflict and its place in relation to the depressive position and developmental processes. PMID:11144856</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25515178','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25515178"><span id="translatedtitle">Seeing the unseen: Charles Bonnet syndrome <span class="hlt">revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Nair, Aditya Gopinathan; Nair, Akshay Gopinathan; Shah, Bharat R; Gandhi, Rashmin Anilkumar</p> <p>2015-09-01</p> <p>Charles Bonnet syndrome (CBS) is a rare condition that encompasses three clinical features: complex visual hallucinations, ocular pathology causing visual deterioration, and preserved cognitive status. Common associated ocular pathologies include age-related macular degeneration, glaucoma, and cataracts. Several theories have been proposed to try to explain the visual hallucinations. However, the pathophysiology remains poorly understood, and treatment is largely based on anecdotal data. The lack of awareness of CBS among medical professionals often leads to inappropriate diagnosis and medication. In a country like India, where awareness of mental health is not widespread, cultural myths and stigma prevent patients from seeking professional help. Here we describe two cases of CBS and <span class="hlt">revisit</span> different ocular morbidities that have been reported to occur in conjunction with CBS. Psychiatrists and ophthalmologists alike must be sensitive to this clinical condition to ensure prompt diagnosis and treatment. PMID:25515178</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..14.5491K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..14.5491K"><span id="translatedtitle"><span class="hlt">Revisiting</span> Cometary Bow Shock Positions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Koenders, C.; Glameier, K.-H.; Nabert, C.; Richter, I.</p> <p>2012-04-01</p> <p>The interaction region between the exosphere of a comet and the solar wind reveals a variety of plasma structures and boundaries which are predicted by several plasma <span class="hlt">models</span> and/or have been observed by a spacecraft mission, e.g. by the GIOTTO mission to comet 1P/Halley and 26P/Grigg-Skjellerup. With regard to the arrival of the next cometary spacecraft mission ROSETTA at its target comet 67P/Churyumov-Gerasimenko (CG), it is necessary to develop <span class="hlt">models</span> of the estimated positions of the different plasma boundaries. This knowledge will be used for the mission planning of the ROSETTA mission in order to prepare the required trajectories for the measurements, to ensure the scientific success of this unique mission. One of the boundaries in the interaction region, which is of particular interest for the mission planning, is the bow shock, where the supersonic flow is strongly decelerated to subsonic velocities. This boundary has been first predicted by Biermann et al. [1967]. They used a one-dimensional hydrodynamical <span class="hlt">model</span> to describe the plasma flow in front of the bow shock. As a result, they ascertained that the velocity of the plasma decreases during the injection of mass into the flow. Furthermore, they found a point at which the mean molecular weight of the plasma normalised by proton mass reaches the critical value of 4/3. Hence, Biermann et al. [1967] suggested that the bow shock is located at this position. For typical solar wind conditions at 1.3 AU and a gas production rate of 5 1027 1/s this point would be 5557 km in front of comet CG. However, more recent numerical simulation results of Hansen et al. [2007] and Gortsas et al. [2010] for the same set of parameters forecast distances of 3500 km and 1764 km, respectively. Using the A.I.K.E.F. hybrid code, we present detailed further simulations and determinations of the bow shock stand-off distance. Deviations from the earlier results by Biermann et al. [1967] are discussed and explained.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PMB....60.1613E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PMB....60.1613E"><span id="translatedtitle">Randoms and TOF gain <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Eriksson, Lars; Conti, Maurizio</p> <p>2015-02-01</p> <p>Time-of-flight (TOF) positron emission tomography (PET) typically reduces the variance in the images by a factor that is proportional to the size of the object to be scanned, and inversely proportional to the time resolution of the PET scanner. Attempts to better characterize this relationship and understand its limits have been published, showing that such gain also increases with random fraction. In this paper, new experimental and simulated data are analyzed and old results are incorporated in the study. The proportionality of TOF gain with time resolution is confirmed, the proportionality constant is measured, the effect of the randoms is validated, and the limit of the <span class="hlt">model</span> for small objects is investigated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3667247','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3667247"><span id="translatedtitle">The rhizosphere <span class="hlt">revisited</span>: root microbiomics</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Bakker, Peter A. H. M.; Berendsen, Roeland L.; Doornbos, Rogier F.; Wintermans, Paul C. A.; Pieterse, Corn M. J.</p> <p>2013-01-01</p> <p>The rhizosphere was defined over 100 years ago as the zone around the root where microorganisms and processes important for plant growth and health are located. Recent studies show that the diversity of microorganisms associated with the root system is enormous. This rhizosphere microbiome extends the functional repertoire of the plant beyond imagination. The rhizosphere microbiome of Arabidopsis thaliana is currently being studied for the obvious reason that it allows the use of the extensive toolbox that comes with this <span class="hlt">model</span> plant. Deciphering plant traits that drive selection and activities of the microbiome is now a major challenge in which Arabidopsis will undoubtedly be a major research object. Here we review recent microbiome studies and discuss future research directions and applicability of the generated knowledge. PMID:23755059</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26743500','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26743500"><span id="translatedtitle">Budded baculovirus particle structure <span class="hlt">revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wang, Qiushi; Bosch, Berend-Jan; Vlak, Just M; van Oers, Monique M; Rottier, Peter J; van Lent, Jan W M</p> <p>2016-02-01</p> <p>Baculoviruses are a group of enveloped, double-stranded DNA insect viruses with budded (BV) and occlusion-derived (ODV) virions produced during their infection cycle. BVs are commonly described as rod shaped particles with a high apical density of protein extensions (spikes) on the lipid envelope surface. However, due to the fragility of BVs the conventional purification and electron microscopy (EM) staining methods considerably distort the native viral structure. Here, we use cryo-EM analysis to reveal the near-native morphology of two intensively studied baculoviruses, Autographa californica multicapsid nucleopolyhedrovirus (AcMNPV) and Spodoptera exigua MNPV (SeMNPV), as <span class="hlt">models</span> for BVs carrying GP64 and F as envelope fusion protein on the surface. The now well-preserved AcMNPV and SeMNPV BV particles have a remarkable elongated, ovoid shape leaving a large, lateral space between nucleocapsid (NC) and envelope. Consistent with previous findings the NC has a distinctive cap and base structure interacting tightly with the envelope. This tight interaction may explain the partial retaining of the envelope on both ends of the NC and the disappearance of the remainder of the BV envelope in the negative-staining EM images. Cryo-EM also reveals that the viral envelope contains two layers with a total thickness of ?6-7nm, which is significantly thicker than a usual biological membrane (<4nm) as measured by X-ray scanning. Most spikes are densely clustered at the two apical ends of the virion although some envelope proteins are also found more sparsely on the lateral regions. The spikes on the surface of AcMNPV BVs appear distinctly different from those of SeMNPV. Based on our observations we propose a new near-native structural <span class="hlt">model</span> of baculovirus BVs. PMID:26743500</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/24857052','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/24857052"><span id="translatedtitle">Cancer log-kill <span class="hlt">revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Norton, Larry</p> <p>2014-01-01</p> <p>At the root of science lie basic rules, if we can discover or deduce them. This is not an abstract project but practical; if we can understand the why then perhaps we can rationally intervene. One of the unifying unsolved problems in physics is the hypothetical "Theory of Everything." In a similar vein, we can ask whether our own field contains such hidden fundamental truths and, if so, how we can use them to develop better therapies and outcomes for our patients. Modern oncology has developed as drugs and translational science have matured over the 50 years since ASCO's founding, but almost from that beginning tumor <span class="hlt">modeling</span> has been a key tool. Through this general approach Norton and Simon changed our understanding of cancer biology and response to therapy when they described the fit of Gompertzian curves to both clinical and animal observations of tumor growth. The practical relevance of these insights has only grown with the development of DNA sequencing promising a raft of new targets (and drugs). In that regard, Larry Norton's contribution to this year's Educational Book reminds us to always think creatively about the fundamental problems of tumor growth and metastases as well as therapeutic response. Demonstrating the creativity and thoughtfulness that have marked his remarkable career, he now incorporates a newer concept of self-seeding to further explain why Gompertzian growth occurs and, in the process, provides a novel potential therapeutic target. As you read his elegantly presented discussion, consider how this understanding, wisely applied to the modern era of targeted therapies, might speed the availability of better treatments. But even more instructive is his personal <span class="hlt">model</span>-not only the Norton-Simon Hypothesis-of how to live and approach science, biology, patients and their families, as well as the broader community. He shows that with energy, enthusiasm, optimism, intellect, and hard work we can make the world better. Clifford A. Hudis, MD, FACP, 2013-2014 ASCO President. PMID:24857052</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AIPC.1677k0007D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AIPC.1677k0007D"><span id="translatedtitle">Groundwater and river water interaction on Cikapundung River: <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Darul, A.; Irawan, D. E.; Trilaksono, N. J.</p> <p>2015-09-01</p> <p>The interaction between groundwater and Cikapundung river water has not changed significantly in 16 years of period. This paper <span class="hlt">revisit</span> the similar research based on 43 measurement points: 13 dug wells, 2 springs, and 24 river, distributed along the riverbank at Curug Dago to Batununggal segment. The field measurements were taken in rainy season of April to May 2014 using portable instruments. Six parameters were measured: water level, temperature, total dissolved solids (TDS), dissolved-oxygen (DO), and pH. The new <span class="hlt">model</span> is unable to detect significant change in water flow, however it finds two local anomalies in Dago Pojok and Cikapayang area. Both locations show local drawdown circle which can induce influent stream in overal effluent environment. Moreover, water quality parameters indicate mixing processes between groundwater and river water, with erratic pattern both in effluent and influent stream. Also some DO and TDS readings exceed the permissible limit. These values suggest a lifted groundwater mineralization from organic and non-organic sources and change of chemical stability. The source of contamination is still under further examination.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ApJ...805...59I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ApJ...805...59I"><span id="translatedtitle">Impulsive Spot Heating and Thermal Explosion of Interstellar Grains <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ivlev, A. V.; Rcker, T. B.; Vasyunin, A.; Caselli, P.</p> <p>2015-05-01</p> <p>The problem of the impulsive heating of dust grains in cold, dense interstellar clouds is <span class="hlt">revisited</span> theoretically with the aim of better understanding the leading mechanisms of the explosive desorption of icy mantles. We rigorously show that if the heating of a reactive medium occurs within a sufficiently localized spot (e.g., the heating of mantles by cosmic rays (CRs)), then the subsequent thermal evolution is characterized by a single dimensionless number ?. This number identifies a bifurcation between two distinct regimes: when ? exceeds a critical value (threshold), the heat equation exhibits the explosive solution, i.e., the thermal (chemical) explosion is triggered. Otherwise, thermal diffusion causes the deposited heat to spread over the entire grainthis regime is commonly known as whole-grain heating. The theory allows us to find a critical combination of physical parameters that govern the explosion of icy mantles due to impulsive spot heating. In particular, our calculations suggest that heavy CR species (e.g., iron ions) colliding with dust are able to trigger the explosion. Based on recently calculated local CR spectra, we estimate the expected rate of explosive desorption. The efficiency of the desorption, which in principle affects all solid species independent of their binding energy, is shown to be comparable to other CR desorption mechanisms typically considered in the literature. Also, the theory allows us to estimate the maximum abundances of reactive species that may be stored in the mantles, which provides important constraints on the available astrochemical <span class="hlt">models</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015MNRAS.451.4384T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015MNRAS.451.4384T"><span id="translatedtitle">Magnetic field-gas density relation and observational implications <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tritsis, A.; Panopoulou, G. V.; Mouschovias, T. Ch.; Tassis, K.; Pavlidou, V.</p> <p>2015-08-01</p> <p>We <span class="hlt">revisit</span> the relation between magnetic-field strength (B) and gas density (?) for contracting interstellar clouds and fragments (or, cores), which is central in observationally determining the dynamical importance of magnetic fields in cloud evolution and star formation. Recently, it has been claimed that a relation B ? ?2/3 is statistically preferred over B ? ?1/2 in molecular clouds, when magnetic-field detections and non-detections from Zeeman observations are combined. This finding has unique observational implications on cloud and core geometry: the relation B ? ?2/3 can only be realized under spherical contraction. However, no indication of spherical geometry can be found for the objects used in the original statistical analysis of the B-? relation. We trace the origin of the inconsistency to simplifying assumptions in the statistical <span class="hlt">model</span> used to arrive at the B ? ?2/3 conclusion and to an underestimate of observational uncertainties in the determination of cloud and core densities. We show that, when these restrictive assumptions are relaxed, B ? ?1/2 is the preferred relation for the (self-gravitating) molecular-cloud data, as theoretically predicted four decades ago.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/16229988','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/16229988"><span id="translatedtitle">Factor structure and external validity of the PANSS <span class="hlt">revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Van den Oord, Edwin J C G; Rujescu, Dan; Robles, Jaime R; Giegling, Ina; Birrell, Claire; Bukszr, Jzsef; Murrelle, Lenn; Mller, Hans-Jrgen; Middleton, Lefkos; Muglia, Pierandrea</p> <p>2006-02-28</p> <p>Considerable controversy exists concerning the positive and negative syndrome scale (PANSS), one of the most widely used instruments in schizophrenia research. In this article we <span class="hlt">revisited</span> the factor structure and external validity of the PANSS in a sample of 500 participants with DSM IV diagnoses of schizophrenia. We found that a <span class="hlt">model</span> with six latent factors provided a relatively good fit, considered adequate by two rules of thumb. Five factors corresponded closely to those typically derived in other studies: Negative, Positive, Excited/Activation, Anxious-Depressed/Dysphoric, and Disorganized/Autistic preoccupation. The sixth factor seemed to have face validity and was labeled Withdrawn. With the exception of Anxious-Depressed/Dysphoric, Cronbach's Alpha ranged from 0.70 to 0.85 suggesting an acceptable internal consistency. External validity was studied through correlations with socio-demographic variables, DSM IV (subtype) diagnoses, clinical characteristics, and drug use. The many significant correlations suggested that the six PANSS scales measure meaningful aspects of schizophrenia. Furthermore, the pattern of correlations varied, providing evidence that the scales assessed partly different aspects of the disease. Our analyses also suggested that some of the controversy about the PANSS can possibly be attributed to methodological factors where the substantial cross-loadings of some PANSS items may play an important role. PMID:16229988</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_24 --> <div id="page_25" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active"><span>25</span></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="481"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26566482','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26566482"><span id="translatedtitle">Fever tree <span class="hlt">revisited</span>: From malaria to autoinflammatory diseases.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Pastore, Serena; Vuch, Josef; Bianco, Anna Monica; Taddio, Andrea; Tommasini, Alberto</p> <p>2015-11-01</p> <p>Over the centuries the idea of recurrent fevers has mainly been associated with malaria, but many other fevers, such as typhoid and diphtheria were cause for concern. It is only in recent times, with the more severe forms of fever from infectious origin becoming less frequent or a cause for worry that we started noticing recurrent fevers without any clear infectious cause, being described as having a pathogenesis of autoinflammatory nature. The use of molecular examinations in many cases can allow a diagnosis where the cause is monogenic. In other cases, however the pathogenesis is likely to be multifactorial and the diagnostic-therapeutic approach is strictly clinical. The old fever tree paradigm developed to describe fevers caused by malaria has been <span class="hlt">revisited</span> here to describe today's periodic fevers from the periodic fever adenitis pharyngitis aphthae syndrome to the more rare autoinflammatory diseases. This <span class="hlt">model</span> may allow us to place cases that are yet to be identified which are likely to be of multifactorial origin. PMID:26566482</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3987381','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3987381"><span id="translatedtitle">Incessant ovulation and ovarian cancer a hypothesis <span class="hlt">re-visited</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Fathalla, M.F.</p> <p>2013-01-01</p> <p>Ovarian cancer continues to be a silent killer. Most women have advanced disease at the time of diagnosis. Intensive efforts to develop effective screening strategies have not so far met with success. There is a need to <span class="hlt">re-visit</span> the potential of prevention strategies. In 1971, the author submitted a hypothesis for a possible relationship between incessant ovulation and development of epithelial ovarian cancer. Subsequent research from different disciplines opened new frontiers to be explored for prevention in the general population and in high-risk groups, and for opportunistic interventions. The protective effect of oral contraceptive pills has been well documented. Widespread use of the pill in the past several decades is credited with a fall in the incidence of ovarian cancer in the general population, countering the effect of low parity. Removing the barriers against contraceptive access and satisfying the still unmet contraceptive need could expand the protective coverage. Enhanced understanding of the biological mechanisms involved in process of ovulation offers the promise of non-hormonal pharmacologic suppression of follicle rupture for women who have risk factors and do not need contraception. The evidence for a possible origin of epithelial cancer in the fimbria of the Fallopian tube presents an opportunity for preventive intervention, during hysterectomy, where salpingectomy alone may provide protection while one or both ovaries are conserved. Finally, the incessant ovulator egg-laying hen has demonstrated its potential as an experimental <span class="hlt">model</span> for chemoprevention of epithelial ovarian cancer. PMID:24753957</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4637800','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4637800"><span id="translatedtitle">Fever tree <span class="hlt">revisited</span>: From malaria to autoinflammatory diseases</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Pastore, Serena; Vuch, Josef; Bianco, Anna Monica; Taddio, Andrea; Tommasini, Alberto</p> <p>2015-01-01</p> <p>Over the centuries the idea of recurrent fevers has mainly been associated with malaria, but many other fevers, such as typhoid and diphtheria were cause for concern. It is only in recent times, with the more severe forms of fever from infectious origin becoming less frequent or a cause for worry that we started noticing recurrent fevers without any clear infectious cause, being described as having a pathogenesis of autoinflammatory nature. The use of molecular examinations in many cases can allow a diagnosis where the cause is monogenic. In other cases, however the pathogenesis is likely to be multifactorial and the diagnostic-therapeutic approach is strictly clinical. The old fever tree paradigm developed to describe fevers caused by malaria has been <span class="hlt">revisited</span> here to describe today’s periodic fevers from the periodic fever adenitis pharyngitis aphthae syndrome to the more rare autoinflammatory diseases. This <span class="hlt">model</span> may allow us to place cases that are yet to be identified which are likely to be of multifactorial origin. PMID:26566482</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4241300','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4241300"><span id="translatedtitle">Psychological Well-Being <span class="hlt">Revisited</span>: Advances in Science and Practice</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Ryff, Carol D.</p> <p>2014-01-01</p> <p>This article reviews the research and interventions that have grown up around a <span class="hlt">model</span> of psychological well-being (Ryff, 1989) generated more than two decades ago to address neglected aspects of positive functioning, such as purposeful engagement in life, realization of personal talents and capacities, and enlightened self-knowledge. The conceptual origins of this formulation are <span class="hlt">revisited</span> and scientific products emerging from six thematic areas are examined: (1) how well-being changes across adult development and later life, (2) what are the personality correlates of well-being, (3) how well-being is linked with experiences in family life, (4) how well-being relates to work and other community activities, (5) what are the connections between well-being and health, including biological risk factors, (6) and via clinical and intervention studies, how psychological well-being can be promoted for ever greater segments of society. Together, these topics illustrate flourishing interest across diverse scientific disciplines in understanding adults as striving, meaning-making, proactive organisms who are actively negotiating the challenges of life. A take-home message is that increasing evidence supports the health protective features of psychological well-being in reducing risk for disease and promoting length of life. A recurrent and increasingly important theme is resilience – the capacity to maintain or regain well-being in the face of adversity. Implications for future research and practice are considered. PMID:24281296</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003JChEd..80..796D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003JChEd..80..796D"><span id="translatedtitle">Synthesis of Zinc Iodide <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Demeo, Stephen</p> <p>2003-07-01</p> <p>Two inquiry-based labs that complement a previously published activity in this Journal, "The Synthesis and Decomposition of Zinc Iodide: <span class="hlt">Model</span> Reactions for Investigating Chemical Change in the Introductory Laboratory", are described. These two experiments could be of interest to introductory chemistry instructors at the college or high school level who teach their students about limiting and excess stoichiometry as well as acid base chemistry. The inquiry-based experiments center on alternate reaction pathways involving a second synthesis of zinc iodide and a side reaction that produces zinc hydroxide. In the first experiment, students draw upon their understanding of solubility and molarity to propose a synthesis of zinc iodide from a double replacement reaction involving zinc sulfate and barium iodide. Students compare the double replacement reaction with the elemental synthesis in terms of percentage yield, efficiency, safety, and cost. In the second experiment, students are asked to identify a white precipitate that forms during a synthesis of zinc iodide from its elements when a specific reagent, acetic acid, is not used. By referring to the literature and conducting qualitative tests, students determine that the white product is zinc hydroxide, a base produced from the hydrolysis of zinc ion.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25082729','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25082729"><span id="translatedtitle">Software package SIMPRE--<span class="hlt">revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Karbowiak, Miros?aw; Rudowicz, Czes?aw</p> <p>2014-10-01</p> <p>This article elucidates the pitfalls identified in the software package SIMPRE recently developed by Baldov et al. (J. Comput. Chem. 2013, 34, 1961) for <span class="hlt">modeling</span> the spectroscopic and magnetic properties of single ion magnets as well as single-molecule magnets. Analysis of the methodology used therein reveals that the crystal field parameters (CFPs), expressed nominally in the Stevens formalism, exhibit features characteristic for the CFPs expressed in the Wybourne notation. The resemblance of the two types of CFPs introduces a serious confusion that may lead to wrong comparisons of the CFPs taken from various sources. To clarify this confusion, the properties of the CFPs Bkq ( Akq, Ckq) associated with the Stevens operators Okq(X?=?S, J, or L), which belong to the class of the tesseral-tensor operators, are contrasted with those of the CFPs Bkq associated with the Wybourne operators Cq(k), which belong to the class of the spherical-tensor operators. Importantly, the confused properties of Stevens and Wybourne operators may bear on reliability of SIMPRE calculations. To consider this question independent calculations are carried out using the complete approach and compared with those of the restricted approach utilized earlier. It appears that the numerical results of the package SIMPRE are formally acceptable, however, the meaning of the CFPs must be properly reformulated. Several other conceptual problems arising from misinterpretations of the crucial notions and the CFP notations identified therein are also discussed and clarified. PMID:25082729</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016A%26A...586A..65D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016A%26A...586A..65D"><span id="translatedtitle">Deuterated polycyclic aromatic hydrocarbons: <span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Doney, K. D.; Candian, A.; Mori, T.; Onaka, T.; Tielens, A. G. G. M.</p> <p>2016-02-01</p> <p>Aims: The amount of deuterium locked up in polycyclic aromatic hydrocarbons (PAHs) has to date been an uncertain value. We present a near-infrared (NIR) spectroscopic survey of Hii regions in the Milky Way, Large Magellanic Cloud, and Small Magellanic Cloud obtained with AKARI, which aims to search for features indicative of deuterated PAHs (PAD or Dn-PAH) to better constrain the D/H ratio of PAHs. Methods: Fifty-three Hii regions were observed in the NIR (2.5-5 μm), using the Infrared Camera (IRC) on board the AKARI satellite. Through comparison of the observed spectra with a theoretical <span class="hlt">model</span> of deuterated PAH vibrational modes, the aromatic and (a)symmetric aliphatic C-D stretch modes were identified. Results: We see emission features between 4.4-4.8 μm, which could be unambiguously attributed to deuterated PAHs in only six of the observed sources, all of which are located in the Milky Way. In all cases, the aromatic C-D stretching feature is weaker than the aliphatic C-D stretching feature, and, in the case of M17b, this feature is not observed at all. Based on the weak or absent PAD features in most of the observed spectra, it is suggested that the mechanism for PAH deuteration in the ISM is uncommon.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22130976','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22130976"><span id="translatedtitle">PHOTOEVAPORATION OF CIRCUMSTELLAR DISKS <span class="hlt">REVISITED</span>: THE DUST-FREE CASE</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Tanaka, Kei E. I.; Omukai, Kazuyuki; Nakamoto, Taishi</p> <p>2013-08-20</p> <p>Photoevaporation by stellar ionizing radiation is believed to play an important role in the dispersal of disks around young stars. The mass-loss <span class="hlt">model</span> for dust-free disks developed by Hollenbach et al. is currently regarded as the conventional one and has been used in a wide variety of studies. However, the rate in this <span class="hlt">model</span> was derived using the crude so-called 1+1D approximation of ionizing radiation transfer, which assumes that diffuse radiation propagates in a direction vertical to the disk. In this study, we <span class="hlt">revisit</span> the photoevaporation of dust-free disks by solving the two-dimensional axisymmetric radiative transfer for steady-state disks. Unlike that solved by the conventional <span class="hlt">model</span>, we determine that direct stellar radiation is more important than the diffuse field at the disk surface. The radial density distribution at the ionization boundary is represented by a single power law with index -3/2 in contrast to the conventional double power law. For this distribution, the photoevaporation rate from the entire disk can be written as a function of the ionizing photon emissivity {Phi}{sub EUV} from the central star and the disk outer radius r{sub d} as follows: M-dot{sub PE} = 5.4 x 10{sup -5} ({Phi}{sub EUV}/10{sup 49} s{sup -1}){sup 1/2} (r{sub d}/1000 AU){sup 1/2} M{sub Sun} yr{sup -1}. This new rate depends on the outer disk radius rather than on the gravitational radius as in the conventional <span class="hlt">model</span>, because of the enhanced contribution to the mass loss from the outer disk annuli. In addition, we discuss its applications to present-day as well as primordial star formation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/16355743','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/16355743"><span id="translatedtitle">The Hermann grid illusion <span class="hlt">revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Schiller, Peter H; Carvey, Christina E</p> <p>2005-01-01</p> <p>The Hermann grid illusion consists of smudges perceived at the intersections of a white grid presented on a black background. In 1960 the effect was first explained by a theory advanced by Baumgartner suggesting the illusory effect is due to differences in the discharge characteristics of retinal ganglion cells when their receptive fields fall along the intersections versus when they fall along non-intersecting regions of the grid. Since then, others have claimed that this theory might not be adequate, suggesting that a <span class="hlt">model</span> based on cortical mechanisms is necessary [Lingelbach et al, 1985 Perception 14(1) A7; Spillmann, 1994 Perception 23 691 708; Geier et al, 2004 Perception 33 Supplement, 53; Westheimer, 2004 Vision Research 44 2457 2465]. We present in this paper the following evidence to show that the retinal ganglion cell theory is untenable: (i) varying the makeup of the grid in a manner that does not materially affect the putative differential responses of the ganglion cells can reduce or eliminate the illusory effect; (ii) varying the grid such as to affect the putative differential responses of the ganglion cells does not eliminate the illusory effect; and (iii) the actual spatial layout of the retinal ganglion cell receptive fields is other than that assumed by the theory. To account for the Hermann grid illusion we propose an alternative theory according to which the illusory effect is brought about by the manner in which S1 type simple cells (as defined by Schiller et al, 1976 Journal of Neurophysiology 39 1320-1333) in primary visual cortex respond to the grid. This theory adequately handles many of the facts delineated in this paper. PMID:16355743</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFM.V11H..08B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFM.V11H..08B"><span id="translatedtitle">Zircon Saturation Re-<span class="hlt">Revisited</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Boehnke, P.; Trail, D.; Schmitt, A. K.; Watson, E. B.; Harrison, M.</p> <p>2011-12-01</p> <p>Zircon saturation in silicate melts has been utilized for magma thermometry and predicting the survival of zircon xenocrysts in crustal melts for nearly 30 years. The original calibration, which assumed only compositional (M = [2Ca+Na+K]/[AlxSi]) and temperature controls, was bolstered by subsequent experimental investigations and thermometry of volcanic rocks and glasses. These latter studies, while confirming the general predictions of the <span class="hlt">model</span>, suggested that other environmental parameters (e.g., pressure, H 2O, halogens, [Fe], oxygen fugacity, etc.) might have second-order effects. Given the tremendous advances in micro-analytical capabilities over the intervening three decades, we have returned to this question with a view to obtaining a refined zircon solubility calibration as a function of P, T, [H2O] and FM (= [Na+K+2(Ca+Mg+Fe)]/[AlxSi]). Detailed SEM imaging of the original low-temperature crystallization experiments (1.2-2.1 kbar) revealed limitations of this approach and we chose instead to use a new experimental design in which shattered Mud Tank zircon is infiltrated by melts of selected composition and water contents. 10 kbar hydrothermal experiments (925o and 850oC) were run for sufficiently long durations (2 to 3 days) to ensure microscale diffusive equilibration of Zr released by zircon dissolution into the intercrystalline melt pools. Sectioned run products were analyzed by SIMS ion imaging of selected areas where glass is exposed in close proximity to or surrounded by Mud Tank zircon fragments. Ion imaging has the advantage of permitting high spatial resolution (3 ?m) analysis of the glasses allowing assessment of Zr equilibration. Using synthetic glass standards, we found [Zr] in anhydrous glasses to be enhanced by ca. 20% relative to hydrous (at 6 wt.% H2O). Our new experiments and re-analysis of the earlier glasses broadly reproduce the original calibration, albeit with substantially enhanced (factor of five) precision compared to the original EMPA analyses. Thus it appears that no significant pressure effect exists up to at least 10 kbar. Ongoing work will expand the pressure range beyond this limit and explore a greater compositional space than previously constrained.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/21680390','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/21680390"><span id="translatedtitle">Dynamics of dolphin porpoising <span class="hlt">revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Weihs, D</p> <p>2002-11-01</p> <p>Porpoising is the popular name for the high-speed surface piercing motion of dolphins and other species, in which long, ballistic jumps are alternated with sections of swimming close to the surface. The first analysis of this behavior (Au and Weihs, 1980) showed that above a certain "crossover" speed this behavior is energetically advantageous, as the reduction in drag due to movement in the air becomes greater than the added cost of leaping.Since that publication several studies documented porpoising behavior at high speeds. The observations indicated that the behavior was more complex than previously assumed. The leaps were interspersed with relatively long swimming bouts, of about twice the leap length. In the present paper, the possibility of dolphins using a combination of leaping and burst and coast swimming is examined. A three-phase <span class="hlt">model</span> is proposed, in which the dolphin leaps out of the water at a speed U(f), which is the final speed obtained at the end of the burst phase of burst and coast swimming. The leap is at constant speed and so the animal returns to the water at U(f), goes to a shallow depth and starts horizontal coasting while losing speed, till it reaches U(i). At that point it starts active swimming, accelerating to U(f). It then starts the next leap. Ranges of speeds for which this three-stage swimming is advantageous are calculated as a function of animal and physical parameters.NotationC-Constant defined in equation (12)C(D)-Coasting drag coefficientD-Dragg-Gravitational accelerationH-Height of jumpJ-Energy required for jumpk-Ratio of swim length to jump lengthl-DistanceL-Total distance (eq. 28)m-Added massM-Animal massM(1)-Total massr-Coefficient defined in eq. (22)R-Ratio of energies, for three-phase swimmingR(2)-Ratio of energies, for burst and coast swimmingt-TimeT-ThrustU-SpeedV-Body volumeW-Weight?-Emergence (=return) angle?-Swim / coast drag penalty ratio?-Surface effects drag ratio?-Density of seawater and cetacean.Subscriptsa-airav-Averageb-Burst phasec-Coast phasee-Reference (maximal) thrustf-Final, at end of bursti-Initial, at start of burstj-Jump phasen-Nominal reference thrusto-Optimals-Surface swimmingw-Water. PMID:21680390</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19930005146','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19930005146"><span id="translatedtitle">Mantle plumes on Venus <span class="hlt">revisited</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kiefer, Walter S.</p> <p>1992-01-01</p> <p>The Equatorial Highlands of Venus consist of a series of quasicircular regions of high topography, rising up to about 5 km above the mean planetary radius. These highlands are strongly correlated with positive geoid anomalies, with a peak amplitude of 120 m at Atla Regio. Shield volcanism is observed at Beta, Eistla, Bell, and Atla Regiones and in the Hathor Mons-Innini Mons-Ushas Mons region of the southern hemisphere. Volcanos have also been mapped in Phoebe Regio and flood volcanism is observed in Ovda and Thetis Regiones. Extensional tectonism is also observed in Ovda and Thetis Regiones. Extensional tectonism is also observed in many of these regions. It is now widely accepted that at least Beta, Atla, Eistla, and Bell Regiones are the surface expressions of hot, rising mantel plumes. Upwelling plumes are consistent with both the volcanism and the extensional tectonism observed in these regions. The geoid anomalies and topography of these four regions show considerable variation. Peak geoid anomalies exceed 90 m at Beta and Atla, but are only 40 m at Eistla and 24 m at Bell. Similarly, the peak topography is greater at Beta and Atla than at Eistla and Bell. Such a range of values is not surprising because terrestrial hotspot swells also have a side range of geoid anomalies and topographic uplifts. Kiefer and Hager used cylindrical axisymmetric, steady-state convection calculations to show that mantle plumes can quantitatively account for both the amplitude and the shape of the long-wavelength geoid and topography at Beta and Atla. In these <span class="hlt">models</span>, most of the topography of these highlands is due to uplift by the vertical normal stress associated with the rising plume. Additional topography may also be present due to crustal thickening by volcanism and crustal thinning by rifting. Smrekar and Phillips have also considered the geoid and topography of plumes on Venus, but they restricted themselves to considering only the geoid-topography ratio and did not examine either the geoid and topography amplitudes separately or the shapes of anomalies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2001A%26A...380..341B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2001A%26A...380..341B"><span id="translatedtitle">Coronal loop hydrodynamics. The solar flare observed on November 12, 1980 <span class="hlt">revisited</span>: The UV line emission</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Betta, R. M.; Peres, G.; Reale, F.; Serio, S.</p> <p>2001-12-01</p> <p>We <span class="hlt">revisit</span> a well-studied solar flare whose X-ray emission originating from a simple loop structure was observed by most of the instruments on board SMM on November 12, 1980. The X-ray emission of this flare, as observed with the XRP, was successfully <span class="hlt">modeled</span> previously. Here we include a detailed <span class="hlt">modeling</span> of the transition region and we compare the hydrodynamic results with the UVSP observations in two EUV lines, measured in areas smaller than the XRP rasters, covering only some portions of the flaring loop (the top and the foot-points). The single loop hydrodynamic <span class="hlt">model</span>, which fits well the evolution of coronal lines (those observed with the XRP and the Fe XXI 1354.1 line observed with the UVSP) fails to <span class="hlt">model</span> the flux level and evolution of the O V 1371.3 line.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://dx.doi.org/10.1016/0376-6357(89)90002-8','USGSPUBS'); return false;" href="http://dx.doi.org/10.1016/0376-6357(89)90002-8"><span id="translatedtitle">Predator-prey interactions, resource depression and patch <span class="hlt">revisitation</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Erwin, R.M.</p> <p>1989-01-01</p> <p>Generalist predators may be confronted by different types of prey in different patches: sedentary and conspicuous, cryptic (with or without refugia), conspicuous and nonsocial, or conspicuous and social. I argue that, where encounter rates with prey are of most importance, patch <span class="hlt">revisitation</span> should be a profitable tactic where prey have short 'recovery' times (conspicuous, nonsocial prey), or where anti-predator response (e.g. shoaling) may increase conspicuousness. Predictions are made for how temporal changes in prey encounter rates should affect <span class="hlt">revisit</span> schedules and feeding rates for the 4 different prey types.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/656293','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/656293"><span id="translatedtitle">Evolution of inhomogeneous condensates: Self-consistent variational approach</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Boyanovsky, D.; Cooper, F.; de Vega, H.J.; Sodano, P.</p> <p>1998-07-01</p> <p>We establish a self-consistent variational framework that allows us to study numerically the non-equilibrium evolution of non-perturbative inhomogeneous field configurations including quantum back reaction effects. After discussing the practical merits and disadvantages of different approaches we provide a closed set of local and renormalizable update equations that determine the dynamical evolution of inhomogeneous condensates and can be implemented numerically. These incorporate self-consistently the back reaction of quantum fluctuations and particle production. This program requires the solution of a self-consistent inhomogeneous problem to provide initial Cauchy data for the inhomogeneous condensates and Green`s functions. We provide a simple solvable ansatz for such an initial value problem for the <span class="hlt">sine-Gordon</span> and {phi}{sup 4} quantum field theories in one spatial dimension. We compare exact known results of the <span class="hlt">sine-Gordon</span> <span class="hlt">model</span> to this simple ansatz. We also study the linear sigma <span class="hlt">model</span> in the large N limit in three spatial dimensions as a microscopic <span class="hlt">model</span> for pion production in ultrarelativistic collisions. We provide a solvable self-consistent ansatz for the initial value problem with cylindrical symmetry. For this case we also obtain a closed set of local and renormalized update equations that can be numerically implemented. A novel phenomenon of spinodal instabilities and pion production arises as a result of a Klein paradox for large amplitude inhomogeneous condensate configurations. {copyright} {ital 1998} {ital The American Physical Society}</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013ispi.book.....S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013ispi.book.....S"><span id="translatedtitle">Introduction to the Statistical Physics of Integrable Many-body Systems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Šamaj, Ladislav Å.; Bajnok, Zoltán</p> <p>2013-05-01</p> <p>Preface; Part I. Spinless Bose and Fermi Gases: 1. Particles with nearest-neighbour interactions: Bethe ansatz and the ground state; 2. Bethe ansatz: zero-temperature thermodynamics and excitations; 3. Bethe ansatz: finite-temperature thermodynamics; 4. Particles with inverse-square interactions; Part II. Quantum Inverse Scattering Method: 5. QISM: Yang-Baxter equation; 6. QISM: transfer matrix and its diagonalization; 7. QISM: treatment of boundary conditions; 8. Nested Bethe ansatz for spin-1/2 fermions with delta interactions; 9. Thermodynamics of spin-1/2 fermions with delta interactions; Part III. Quantum Spin Chains: 10. Quantum Ising chain in a transverse field; 11. XXZ Heisenberg chain: Bethe ansatz and the ground state; 12. XXZ Heisenberg chain: ground state in the presence of magnetic field; 13. XXZ Heisenberg chain: excited states; 14. XXX Heisenberg chain: thermodynamics with strings; 15. XXZ Heisenberg chain: thermodynamics without strings; 16. XYZ Heisenberg chain; 17. Integrable isotropic chains with arbitrary spin; Part IV. Strongly Correlated Electrons: 18. Hubbard <span class="hlt">model</span>; 19. Kondo effect; 20. Luttinger many-fermion <span class="hlt">model</span>; 21. Integrable BCS superconductors; Part V. <span class="hlt">Sine-Gordon</span> <span class="hlt">Model</span>: 22. Classical <span class="hlt">sine-Gordon</span> theory; 23. Conformal quantization; 24. Lagrangian quantization; 25. Bootstrap quantization; 26. UV-IR relation; 27. Exact finite volume description from XXZ; 28. Two-dimensional Coulomb gas; Appendix A. Spin and spin operators on chain; Appendix B. Elliptic functions; References; Index.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/24899345','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/24899345"><span id="translatedtitle">[What mirror neurons have revealed: <span class="hlt">revisited</span>].</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Murata, Akira; Maeda, Kazutaka</p> <p>2014-06-01</p> <p>The first paper on mirror neurons was published in 1992. In the span of over two decades since then, much knowledge about the relationship between social cognitive function and the motor control system has been accumulated. Direct matching of visual actions and their corresponding motor representations is the most important functional property of mirror neuron. Many studies have emphasized intrinsic simulation as a core concept for mirror neurons. Mirror neurons are thought to play a role in social cognitive function. However, the function of mirror neurons in the macaque remains unclear, because such cognitive functions are limited or lacking in macaque monkeys. It is therefore important to discuss these neurons in the context of motor function. Rizzolatti and colleagues have stressed that the most important function of mirror neurons in macaques is recognition of actions performed by other individuals. I suggest that mirror neurons in the Macaque inferior pariental lobule might be correlated with body schema. In the parieto-premotor network, matching of corollary discharge and actual sensory feedback is an essential neuronal operation. Recently, neurons showing mirror properties were found in some cortical areas outside the mirror neuron system. The current work would <span class="hlt">revisit</span> the outcomes of mirror neuron studies to discuss the function of mirror neurons in the monkey. PMID:24899345</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22308220','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22308220"><span id="translatedtitle"><span class="hlt">Revisiting</span> the relaxation dynamics of isolated pyrrole</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Montero, Raúl; Ovejas, Virginia; Fernández-Fernández, Marta; Longarte, Asier; Peralta Conde, Álvaro</p> <p>2014-07-07</p> <p>Herein, the interpretation of the femtosecond-scale temporal evolution of the pyrrole ion signal, after excitation in the 267–217 nm interval, recently published by our group [R. Montero, A. Peralta Conde, V. Ovejas, M. Fernández-Fernández, F. Castaño, J. R. Vázquez de Aldana, and A. Longarte, J. Chem. Phys.137, 064317 (2012)] is <span class="hlt">re-visited</span>. The observation of a shift in the pyrrole{sup +} transient respect to zero delay reference, initially attributed to ultrafast dynamics on the πσ{sup *} type state (3s a{sub 1} ← π 1a{sub 2}), is demonstrated to be caused by the existence of pump + probe populated states, along the ionization process. The influence of these resonances in pump-prone ionization experiments, when multi-photon probes are used, and the significance of a proper zero-time reference, is discussed. The possibility of preparing the πσ{sup *} state by direct excitation is investigated by collecting 1 + 1 photoelectron spectra, at excitation wavelengths ranging from 255 to 219 nm. No conclusive evidences of ionization through this state are found.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25168337','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25168337"><span id="translatedtitle">Extrasynaptic NMDA Receptor in Excitotoxicity: Function <span class="hlt">Revisited</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhou, Xianju; Chen, Zhuoyou; Yun, Wenwei; Ren, Jianhua; Li, Chengwei; Wang, Hongbing</p> <p>2015-08-01</p> <p>It is generally accepted that proper activation of N-methyl-d-aspartate receptors (NMDARs) promotes neuronal survival and supports neuroplasticity, and excessive NMDAR activation leads to pathological outcomes and neurodegeneration. As NMDARs are found at both synaptic and extrasynaptic sites, there is significant interest in determining how NMDARs at different subcellular locations differentially regulate physiological as well as pathological functions. Better understanding of this issue may support the development of therapeutic strategies to attenuate neuronal death or promote normal brain function. Although the current prevailing theory emphasizes the major role of extrasynaptic NMDARs in neurodegeneration, there is growing evidence indicating the involvement of synaptic receptors. It is also evident that physiological functions of the brain also involve extrasynaptic NMDARs. Our recent studies demonstrate that the degree of cell death following neuronal insults depends on the magnitude and duration of synaptic and extrasynaptic receptor co-activation. These new results underscore the importance of <span class="hlt">revisiting</span> the function of extrasynaptic NMDARs in cell fate. Furthermore, the development of antagonists that preferentially inhibit synaptic or extrasynaptic receptors may better clarify the role of NMDARs in neurodegeneration. PMID:25168337</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009APS..MARZ29011K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009APS..MARZ29011K"><span id="translatedtitle"><span class="hlt">Revisiting</span> Classical Diamagnetism: A Surprise of Physics</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kumar, Narendra; Krishnamurthy, Vijay Kumar</p> <p>2009-03-01</p> <p>The Classic Bohr-van Leeuwen (BvL) theorem states that the orbital diamagnetism of a classical system of charged particles in thermal equilibrium is identically zero. This theorem is universally accepted and has entered textbooks. Physically, the theorem derives from the exact cancellation of the orbital diamagnetic moment associated with the completed cyclotron orbits of the charged particles by the paramagnetic moment subtended by the incomplete orbits skipping the boundary cuspidally in the opposite sense. In this work we have <span class="hlt">revisited</span> the problem of this crucial but subtle role of the boundary by considering the case of a finite but unbounded system, namely that of a charged particle moving on a sphere in the presence of an externally applied magnetic field. The orbital moment calculated on the basis of the classical Langevin equation in the infinite time limit now indeed turns out to be non-zero, and has the diamagnetic sign. This violates the BvL theorem as stated in the literature. To the best of our knowledge, this is the first report of non-zero classical diamagnetism. It is explicitly owing to the above avoided cancellation. We also present possible experimental realization of the predicted classical diamagnetism.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active"><span>25</span></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_25 --> <center> <div class="footer-extlink text-muted"><small>Some links on this page may take you to non-federal websites. 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