Short acquisition time is essential in cardiac cine magnetic resonance imaging (MRI), in particular for sick patients who have difficulties to hold their breath. This paper investigates the use of two reconstruction methods, initially proposed for static images, for reconstructing cardiac cine images from partial <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>k</mml:mi></mml:math>-space. A new acquisition schema which makes use of temporal redundancies within data is proposed. The results show that, in comparison with the full <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>k</mml:mi></mml:math>-space acquisition, the acquisition time can be reduced by a factor of 4 while obtaining a good reconstruction quality.

Josiane Yankam Njiwa

Yuemin Zhu

Jianhua Luo

Bassem Hiba

Reconstruction of  Cardiac Cine MR Images from Partial<svg style="vertical-align:-0.1638pt" height="12.4375" version="1.1" viewBox="0 0 8.6750002 12.4375" width="8.6750002" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg"><g transform="matrix(.017,-0,0,-.017,.062,12.162)"><path id="x1D458" d="M480 416q0 -21 -18 -41q-9 -11 -17 -7q-20 9 -42 9q-62 0 -140 -78q23 -69 88 -192q17 -31 27 -42t20 -11q16 0 62 46l17 -20q-64 -92 -119 -92q-35 0 -70 66q-41 73 -84 187q-36 -30 -62 -61q-27 -115 -35 -172q-41 -8 -78 -20l-6 6l140 612q7 28 0.5 34t-37.5 7l-34 1&#xA;l5 26q38 4 74 13.5t57 17t25 7.5q12 0 4 -32l-104 -443h2q35 38 97 93q39 35 65.5 56t62 41.5t58.5 20.5q19 0 30.5 -10t11.5 -22z" /></g></svg>-Space

I work out the Newtonian and general relativistic effects due to an
isotropic mass loss <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mover accent="true"><mml:mi>M</mml:mi><mml:mo>&#x02D9;</mml:mo></mml:mover><mml:mo>/</mml:mo><mml:mi>M</mml:mi></mml:mrow></mml:math> of a body on the orbital motion of a test particle around it; the present analysis is also valid for a variation <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mover accent="true"><mml:mi>G</mml:mi><mml:mo>&#x02D9;</mml:mo></mml:mover><mml:mo>/</mml:mo><mml:mi>G</mml:mi></mml:mrow></mml:math> of the Newtonian constant of gravitation. Concerning the Newtonian
case, I use the Gauss equations for the variation of the elements and
obtain negative secular rates for the osculating semimajor axis <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>a</mml:mi></mml:math>, the
eccentricity <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>e</mml:mi></mml:math>, and the mean anomaly <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>&#x02133;</mml:mi></mml:math>, while the argument of pericenter <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>&#x03C9;</mml:mi></mml:math> does not experience secular precession; the longitude of the
ascending node <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>&#x03A9;</mml:mi></mml:math> and the inclination <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>i</mml:mi></mml:math> remain unchanged as well. The true orbit, instead, expands, as shown by a
numerical integration of the equations of motion with MATHEMATICA; in fact, this is in agreement with the seemingly counter-intuitive decreasing of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>a</mml:mi></mml:math> and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>e</mml:mi></mml:math> because they refer to the osculating Keplerian
ellipses which approximate the trajectory at each instant. A comparison with the results obtained with different approaches by other researchers is made. General relativity induces positive secular rates
of the semimajor axis and the eccentricity completely negligible in the
present and future evolution of the solar system.

L. Iorio

Classical and Relativistic Orbital Motions around a Mass-Varying Body

The steady mixed convection boundary layer flow from a solid sphere in a micropolar fluid, generated by Newtonian heating in which the heat transfer from the surface is proportional to the local surface temperature, is considered. The governing boundary layer equations are first transformed into a system of nondimensional equations via the non-dimensional variables, and then into nonsimilar equations before they are solved numerically using an implicit finite-difference scheme known as the Keller-box method. Numerical solutions are obtained for the skin friction coefficient, wall temperature and heat transfer coefficient, as well as the velocity and temperature profiles with several parameters considered, namely the mixed convection parameter, the material or micropolar parameter, and the Prandtl number.

M. Z. Salleh

R. Nazar

I. Pop

Mixed Convection Boundary Layer Flow from a Solid Sphere with Newtonian Heating in a Micropolar Fluid

Stochastic acceleration of charged particles across highly relativistic shock is often considered as the main source for observed emission. Here is shown that the derivation of the appropriate quasilinear equation describing particle transport across such shocks depends on the assumptions made for the power spectra in the upstream region ahead of the shock. For both an ambient magnetic field perpendicular to the shock front and for an oblique magnetic field derivation is given of the quasilinear diffusion equation for particle transport appropriate to both sides of the shock. There is both pitch angle diffusion and energy diffusion; the relative strengths of the two processes depends on the assumptions made concerning the upstream wave power spectra. Transformations of the diffusion equations into the frame where the shock is stationary are given for the upstream and downstream regions including both energy diffusion and pitch angle scattering. The remaining outstanding concern is the determination of the continuity of the transport equations across the shock. This latter problem has yet to be solved fully in even the simple case of assumed pitch angle scattering only. Including energy diffusion and pitch angle scattering presumably makes the determination of the correct continuity behaviour more difficulty.

Ian Lerche

Reinhard Schlickeiser

A Kinetic Approach to Relativistic Shocks in Astrophysics

We study the effects of random long-range connections (shortcuts) on the firing patterns in a network composed of Hindmarsh-Rose neurons. It is found that the system can achieve the transition of neural firing patterns from the lower period state to the higher one, when the number of shortcuts in the neural network is greater than a threshold, indicating that the nervous system may make the optimal response to the change of stimulation by a corresponding adjustment of the shortcuts. Then we discuss the transition degree of firing patterns of neural network and its critical characteristics for different external stimulation current. Furthermore, the influences of coupling strength on such transition behavior of neural firing patterns are also considered. Our results may be useful in comprehending the real mechanism in neural coding and information transmission in neurobiological systems.

Peng Wang

Ji-Qian Zhang

Hai-Lin Ren

Transition of Firing Patterns in a Complex Neural Network

The infrared (IR) spectra of (100-x)<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mtext>TeO</mml:mtext><mml:mn>2</mml:mn></mml:msub></mml:math>&#x2013;x<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mtext>WO</mml:mtext><mml:mn>3</mml:mn></mml:msub></mml:math> glasses reveal that the glass network consists of [<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mtext>TeO</mml:mtext><mml:mn>3</mml:mn></mml:msub></mml:math>]/[<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mtext>TeO</mml:mtext><mml:mrow><mml:mn>3</mml:mn><mml:mo>+</mml:mo><mml:mn>1</mml:mn></mml:mrow></mml:msub></mml:math>], [<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mtext>TeO</mml:mtext><mml:mn>4</mml:mn></mml:msub></mml:math>], [<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mtext>WO</mml:mtext><mml:mn>4</mml:mn></mml:msub></mml:math>], and [<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mtext>WO</mml:mtext><mml:mn>6</mml:mn></mml:msub></mml:math>] groups as basic structural units. Addition of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mtext>WO</mml:mtext><mml:mn>3</mml:mn></mml:msub></mml:math> oxide to the binary <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mtext>TeO</mml:mtext><mml:mn>2</mml:mn></mml:msub></mml:math>&#x2013;W<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mtext>O</mml:mtext><mml:mn>3</mml:mn></mml:msub></mml:math> glasses increases the amount of lower coordination of [<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mtext>TeO</mml:mtext><mml:mn>3</mml:mn></mml:msub></mml:math>]/[<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mtext>TeO</mml:mtext><mml:mrow><mml:mn>3</mml:mn><mml:mo>+</mml:mo><mml:mn>1</mml:mn></mml:mrow></mml:msub></mml:math>] units and decreases the higher coordination of [<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mtext>TeO</mml:mtext><mml:mn>4</mml:mn></mml:msub></mml:math>] units and also the formation of Te&#x2013;O&#x2013;W linkages at the expense of Te&#x2013;O&#x2013;Te linkages. The IR spectra of 60<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mtext>TeO</mml:mtext><mml:mn>2</mml:mn></mml:msub></mml:math>&#x2013;(40-x)<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mtext>WO</mml:mtext><mml:mn>3</mml:mn></mml:msub></mml:math>&#x2013;xPbO glasses reveal that the glass network consists of [<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mtext>TeO</mml:mtext><mml:mn>3</mml:mn></mml:msub></mml:math>], [<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mtext>TeO</mml:mtext><mml:mn>4</mml:mn></mml:msub></mml:math>], [<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mtext>WO</mml:mtext><mml:mn>4</mml:mn></mml:msub></mml:math>], [<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mtext>WO</mml:mtext><mml:mn>6</mml:mn></mml:msub></mml:math>], and [<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mtext>PbO</mml:mtext><mml:mn>4</mml:mn></mml:msub></mml:math>] units. Changes in the coordination state of tellurium and tungsten ions occur when the PbO and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mtext>WO</mml:mtext><mml:mn>3</mml:mn></mml:msub></mml:math> concentrations are varied. The dual role of the lead ions is confirmed in 60<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mtext>TeO</mml:mtext><mml:mn>2</mml:mn></mml:msub></mml:math>&#x2013;(40-x)<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mtext>WO</mml:mtext><mml:mn>3</mml:mn></mml:msub></mml:math>&#x2013;xPbO glass system. The W ion coordination state changes from 4 to 6 when <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mtext>WO</mml:mtext><mml:mn>3</mml:mn></mml:msub></mml:math> concentration increases beyond 30 mol&#37; in both (100-x)<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mtext>TeO</mml:mtext><mml:mn>2</mml:mn></mml:msub></mml:math>&#x2013;x<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mtext>WO</mml:mtext><mml:mn>3</mml:mn></mml:msub></mml:math> and 60<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mtext>TeO</mml:mtext><mml:mn>2</mml:mn></mml:msub></mml:math>&#x2013;(40-x)<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mtext>WO</mml:mtext><mml:mn>3</mml:mn></mml:msub></mml:math>&#x2013;xPbO glass systems. The IR spectra of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mn>60</mml:mn><mml:msub><mml:mtext>B</mml:mtext><mml:mn>2</mml:mn></mml:msub><mml:msub><mml:mtext>O</mml:mtext><mml:mn>3</mml:mn></mml:msub></mml:math>&#x2013;10<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mtext>TeO</mml:mtext><mml:mn>2</mml:mn></mml:msub></mml:math>&#x2013;(30-x)ZnO&#x2013;xPbO glasses reveal that the glass network consists of [<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mtext>TeO</mml:mtext><mml:mn>3</mml:mn></mml:msub></mml:math>], [<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mtext>BO</mml:mtext><mml:mn>3</mml:mn></mml:msub></mml:math>], and [<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mtext>BO</mml:mtext><mml:mn>4</mml:mn></mml:msub></mml:math>] groups.

G. Upender

C. P. Vardhani

V. Kamalaker

V. Chandra Mouli

Infrared Spectroscopic Characterization of Tellurite Glasses Containing Heavy Metal Oxides

The response of ion plasmas to external radiation fields is investigated in a quantum
mechanical formalism. We focus on the total electric field within the plasma. For general bandpass signals three frequency regions can be distinguished in terms of the plasma frequency. For low frequencies, the external field is shielded. For high frequencies, the field is not modified. Resonant behavior of the plasma appears for frequencies near the plasma frequency: large internal electric fields and induced currents are present. These effects may be relevant for biological systems. The model is therefore extended to a two-species plasma and additional interactions are studied. The response is not essentially altered. To make the models more realistic, a so-called bath is included. In the weak coupling approximation the resonance frequency is shifted and some damping occurs. Finite temperature effects on the electric field are absent. The energy of the system, however, depends on temperature.

H. W. L. Naus

Ion Plasma Responses to External Electromagnetic Fields

Quasilinear theory is developed by using canonical variables for a relativistic plasma. It is self-consistent, including momentum, pitch angle, and spatial diffusions. By assuming the wave field as a superposition of known toroidal and poloidal Fourier modes, the quasilinear diffusion coefficients are written in a form which can be directly evaluated using the output of a spectral full-wave solver of Maxwell equations in toroidal plasmas. The formalism is special for tokamas and, therefore, simple and suitable for simulations of cyclotron heating, current drive, and radio-frequency wave-induced radial transport in ITER.

Z. T. Wang

Y. X. Long

J. Q. Dong

Relativistic Quasilinear Description of Three-Dimensional Diffusion

Using successively the conventional Gibbs and the differential-form formulations of Maxwell&#39;s equations, we analyze the electromagnetic fields in a self-dual chiral material (invariance under the exchanges [(<b>E</b><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mo>&#x21D4;</mml:mo></mml:math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mo>&#x2212;</mml:mo></mml:math><b>H</b>), (<b>D</b><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mo>&#x21D4;</mml:mo></mml:math><b>B</b>), <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mrow><mml:mrow><mml:mrow><mml:mo>(</mml:mo><mml:mrow><mml:mi>&#x03B5;</mml:mi><mml:mo>&#x21D4;</mml:mo><mml:mo>&#x2212;</mml:mo><mml:mi>&#x03BC;</mml:mi></mml:mrow><mml:mo>)</mml:mo></mml:mrow></mml:mrow><mml:mo>]</mml:mo></mml:mrow></mml:mrow></mml:math>. We prove  that  such a medium supports pseudo-TE/TM waves (only a component is null with two relations between four of the five other components). An interesting example is supplied by the Courant-Hilbert quasi-undistorted progressing waves: their form does not change along propagation; only their amplitude could change.

Pierre Hillion

Pseudo-TE/TM Waves in a Self-Dual Chiral Medium

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