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Based on the recent results in the generalized Lorenz-Mie theory, solutions for scattering problems of a sphere with an eccentrically located spherical inclusion illuminated by an arbitrary shaped electromagnetic beam in an arbitrary orientation are obtained. Particular attention is paid to the description and application of an arbitrary shaped beam in an arbitrary orientation to the scattering problem under study. The theoretical formalism is implemented in a homemade computer program written in FORTRAN. Numerical results concerning spatial distributions of both internal and external fields are displayed in different formats in order to properly display exemplifying results. More specifically, as an example, we consider the case of a focused fundamental Gaussian beam (TEM(00) mode) illuminating a glass sphere (having a real refractive index equal to 1.50) with an eccentrically located spherical water inclusion (having a real refractive index equal to 1.33). Displayed results are for various parameters of the incident electromagnetic beam (incident orientation, beam waist radius, location of the beam waist center) and of the scatterer system (location of the inclusion inside the host sphere and relative diameter of the inclusion to the host sphere).

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We consider the motion of trajectories in the annular billiard, constituted of a circle with an internal, perfectly reflecting, eccentrically located secondary circle, displaying a generic Hamiltonian behavior (including periodic orbits, invariant curves, and chaotic areas). Periodic orbits embedded in the phase space are systematically investigated, with a focus on inclusion-touching periodic orbits, up to symmetrical orbits of period 6. Candidates for periodic orbits are detected by investigating grayscale distance charts and, afterward, each candidate is validated (or rejected) by using analytical and/or numerical methods. This Hamiltonian problem with Hamiltonian chaos (mechanical language) may equivalently be viewed as an optical problem with optical chaos (expressed with a geometrical optics language). It then may be extended to the study of interaction between a laser beam (or a plane wave as a limit) and a sphere with an eccentrically located spherical inclusion, this interaction being described by a generalized Lorenz-Mie theory recently established. Inclusion-touching periodic orbits in the annular billiard may generate a new class of morphology-dependent resonances in the associated extended generalized Lorenz-Mie theory problem.

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Erwinia chrysanthemi insertion mutants were isolated that grew poorly specifically in the presence of glycine betaine (GB) or its analogues in high-salt media. Transposon insertions were found to affect the bspA gene, which forms an operon including the psd locus coding for phosphatidylserine decarboxylase. Initial GB uptake is not affected by the bspA mutation. However, in high-salt medium, its initial accumulation is followed by a reduced glucose uptake and a release of GB but not a loss of viability. BspA is homologous to the widespread MscS channel, YggB, but does not seem to constitute a mechanosensitive channel. We suggest that BspA is a protein sensing both intracellular GB and the extracellular salt content of the medium, the hypothesis being built on the observation that BspA is necessary to maintain the GB pool during osmoadaptation in high-salt media containing this osmoprotectant.

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Our aim is to present a method of predicting light transmittances through dense three-dimensional layered media. A hybrid method is introduced as a combination of the four-flux method with coefficients predicted from a Monte Carlo statistical model to take into account the actual three-dimensional geometry of the problem under study. We present the principles of the hybrid method, some exemplifying results of numerical simulations, and their comparison with results obtained from Bouguer-Lambert-Beer law and from Monte Carlo simulations.

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Our aim is to present the application of the hybrid method presented in part I to an inverse procedure to determine particle size and concentration under multiple-scattering conditions. The hybrid method is introduced as a combination of the four-flux method with coefficients obtained from Monte Carlo statistical simulations to take into account the actual three-dimensional geometry. Then an inversion scheme is expanded to enable the application of the hybrid method to particle size and concentration determination. We present the inversion method as well as exemplifying results of spectrum inversions.

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The use of the generalized Lorenz-Mie theory (GLMT) requires knowledge of beam-shape coefficients (BSC's) that describe the beam illuminating a spherical scatterer. We theoretically demonstrated that these BSC's can be determined from an actual beam in the laboratory. We demonstrate the effectiveness of our theoretical proposal by determining BSC's for a He-Ne laser beam focused to a diameter of a few micrometers. Once these BSC's are determined, the electromagnetic fields of the illuminating beam may be evaluated. By relying on the GLMT, we can also determine all properties of the interaction between beam and scatterer, including mechanical effects (radiation pressures and torques).

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The scattering of laser pulses (in the femtosecond-picosecond range) by large spheres is investigated. We call a sphere large when its diameter is larger than the length associated with the pulse duration, allowing one to observe the temporal separation of scattering modes including surface waves.

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We demonstrate from a generalized Lorenz-Mie theory that ultrashort pulses can induce superluminal excitation in microdroplets. A ?erenkov-like effect can thus be expected for sufficiently intense ultrashort pulses.

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Rational functions are not very useful for obtaining global differential models because they involve poles that may eject the trajectory to infinity. In contrast, it is here shown that they allow one to significantly improve the quality of models for maps. In such a case, the presence of poles does not involve any numerical difficulty when the models are iterated. The models then take advantage of the ability of rational functions to capture complicated structures that may be generated by maps. The method is applied to experimental data from copper electrodissolution.

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We establish a localized approximation to evaluate the beam-shape coefficients of a Gaussian beam in elliptical cylinder coordinates. As for the case of spherical coordinates and of circular cylinder coordinates, this approximation provides an efficient way to speed up computations within the framework of a generalized Lorenz-Mie theory for elliptical cylinders.

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A myriad different constituents or elements (genes, proteins, lipids, ions, small molecules etc.) participate in numerous physico-chemical processes to create bacteria that can adapt to their environments to survive, grow and, via the cell cycle, reproduce. We explore the possibility that it is too difficult to explain cell cycle progression in terms of these elements and that an intermediate level of explanation is needed. This level is that of hyperstructures. A hyperstructure is large, has usually one particular function, and contains many elements. Non-equilibrium, or even dissipative, hyperstructures that, for example, assemble to transport and metabolize nutrients may comprise membrane domains of transporters plus cytoplasmic metabolons plus the genes that encode the hyperstructure's enzymes. The processes involved in the putative formation of hyperstructures include: metabolite-induced changes to protein affinities that result in metabolon formation, lipid-organizing forces that result in lateral and transverse asymmetries, post-translational modifications, equilibration of water structures that may alter distributions of other molecules, transertion, ion currents, emission of electromagnetic radiation and long range mechanical vibrations. Equilibrium hyperstructures may also exist such as topological arrays of DNA in the form of cholesteric liquid crystals. We present here the beginning of a picture of the bacterial cell in which hyperstructures form to maximize efficiency and in which the properties of hyperstructures drive the cell cycle.

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We present numerical results concerning the properties of the electromagnetic field scattered by an infinite circular cylinder illuminated by a circular Gaussian beam. The cylinder is arbitrarily located and arbitrarily oriented with respect to the illuminating Gaussian beam. Numerical evaluations are provided within the framework of a rigorous electromagnetic theory, the generalized Lorenz-Mie theory, for infinite cylinders. This theory provides new insights that could not be obtained from older formulations, i.e., geometrical optics and plane-wave scattering. In particular, some emphasis is laid on the waveguiding effect and on the rainbow phenomenon whose fine structure is hardly predictable by use of geometrical optics.

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A cylindrical localized approximation to speed up numerical computations in generalized Lorenz-Mie theory for cylinders, in a special case of perpendicular illumination, was recently introduced and rigorously justified. We generalize this approximation to the case when the cylinder is arbitrarily located and arbitrarily oriented in a Gaussian beam.

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Global vector field reconstruction is a well established technique to provide phenomenological models from nonlinear data, in particular when all information is contained in a so-called standard function. In the case when the standard function is taken as a ratio of polynomials, we establish that information about the fixed points of the system can be automatically retrieved from the data, allowing one to build a better model by selecting an appropriate structure. The method is exemplified in the case of the variable z of the Rössler system, which constitutes a rather acid test case.

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The Phase Doppler Anemometer (PDA) technique measures particle diameter assuming sphericity. A means for detecting nonsphericity has usually been implemented in commercial PDA systems to avoid sizing errors if the sphericity assumption is not valid. In the present research the response of standard and planar PDA systems is examined experimentally in more detail by passing nonspherical droplets of known shape through the measurement volume. The effectiveness of nonsphericity detection schemes can be evaluated, and furthermore the influence of the droplet oscillations on the frequency and phase evolution of individual signals can be quantified. The light scattering from such particles has been simulated by using geometric optics, and the computed response of standard and planar PDA systems agrees well with the experimental observations. We conclude with some remarks concerning the possibilities of characterizing the nonsphericity with PDA systems.

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Recently a so-called standard beam description of Gaussian beams was introduced [J. Opt. Soc. Am. A 11, 2503 (1994)]. However, it was afterward observed [Appl. Opt.35, 2702 (1996)] that this description exhibits a finite radius of convergence, limiting its range of applicability. We introduce an improved standard beam description with an infinite radius of convergence. The utility of this improved description is illustrated by evaluation of radiation pressure forces under severe focusing conditions.

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The generalized Lorenz-Mie theory deals with the interaction between spheres and arbitrarily shaped illuminating beams. An efficient use of the theory requires efficient evaluation of the so-called beam-shape coefficients involved in the description of the illuminating beam. A less time-consuming method of evaluation relies on the localized approximation. However, it lacks flexibility when the description of the illuminating beam is modified. We present a new version of this method, called the integral localized approximation, that exhibits the desired property of flexibility.

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The use of the generalized Lorenz-Mie theory that describes the interaction between a spherical particle and an arbitrarily shaped beam requires knowledge of the beam-shape coefficients (BSC's) that describe the illuminating beam. Classically, these BSC's are evaluated from an a priori mathematical description of the illuminating beam. We propose a method that relies on intensity measurements along the beam axis that permits one to measure directly the BSC's of an actual beam in the laboratory.

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The development of initial disturbances is relevant to the understanding of atomization processes in which droplets are generated by the breakup of a liquid jet. We theoretically and experimentally demonstrate that such disturbances can be characterized by rainbow sizing. More specifically, for a liquid jet with a diameter of 600 mum, disturbances in the range from 10 nm to 0.2 mum are accessible.

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An efficient numerical procedure for computing the scattering coefficients of a multilayered sphere is discussed. The stability of the numerical scheme allows us to extend the feasible range of computations, both in size parameter and in number of layers for a given size, by several orders of magnitude with respect to previously published algorithms. Exemplifying results, such as scattering diagrams and cross-sectional curves, including the case of Gaussian beam illumination, are provided. Particular attention is paid to scattering at the rainbow angle for which approaches based on geometrical optics might fail to provide accurate enough results.