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Preface of the "1st symposium on multiscale, multiphysics and turbulent flow simulations"
No full textErratum: Age-dependent decline in learning and memory performances of WAG/Rij rat model of absence epilepsy [Behav Brain Funct. 8 (2012) 51]
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Single glycerol/water microdroplets standing on a superhydrophobic surface: Optical microcavities promising original applications
No full textGlycerol/water microdroplets take almost spherical shapes when standing on a superhydrophobic surface. Hence they are suitable to function as optical microcavities. Using Rhodamine B doped water microdroplets, large spectral tunability of the whispering gallery modes (WGMs) (>5 nm) was observed. Tunability was achieved by evaporation/condensation in a current controlled mini humidity chamber. Experiments revealed a mechanism stabilizing the volume of these microdroplets with femtoliter resolution. The mechanism relied on the interplay between the condensation rate that was kept constant and the size dependent laser induced heating. The radii of individual water microdroplets (>5 mu m) stayed within a few nanometers during long time periods (several minutes). By blocking the laser excitation for 500 msec, the stable volume of individual microdroplets were changed stepwise. Laser emission was also observed from Rhodamine B doped glycerol/water microdroplets using a pulsed, frequency-doubled Nd:YAG laser (lambda=532 nm) as the excitation source. The observed largely tunable WGMs and laser emission can pave way for novel applications in optical communication systems. Besides due to the sensitivity of the WGMs to the size and shape of the microdroplets, the results can find applications in characterizing superhydrophobic surfaces and investigating liquid-solid surfaces
A comparative analysis of austenite-to-martensite and austenite-to-bainite phase transformation kinetics in steels
No full textThis paper presents a comparison of the macroscopic transformation strain evolution as a function of the bainite and martensite phase fractions in steels. Specifically, the evolution of anisotropic strain with phase fraction follows a linear trend for the martensitic transformation due to continuous stress-induced variant selection. In the case of bainitic transformation, the anisotropic strain evolves non-linearly owing to diffusion, minimizing the distortion around the bainitic sheaves and further promoting stress-induced variant selection at the early stages of the bainitic phase transformation. However, this effectiveness is reduced when the bainitic sheaves start constricting the growth of each other
Microstructured head-up display screen for automotive applications
No full textA novel see-through screen is developed for automobiles which reduces the size of the head-up display (HUD) unit considerably. The screen is illuminated by a laser scanning pico-projector and a real image is formed on the screen. The screen has thousands of hexagonally packed microlenses that are partially reflective and embedded in an index matched medium which provides very good see-through capability. Light reflected from the microlenses expand and form a hexagon shaped viewing window. This system is called a direct projection HUD system as the pico projector projects directly onto the screen and forms a real image on it. The system is very compact and does not require any space under the dashboard, which saves on space for the car manufacturers, or allows it to be used immediately as an aftermarket HUD installed in any car
Quantum mechanical symmetries and topological invariants
No full textWe give the definition and explore the algebraic structure of a class of quantum symmetries, called topological symmetries, which are generalizations of supersymmetry in the sense that they involve topological invariants similar to the Witten index. A topological symmetry (TS) is specified by an integer n > 1, which determines its grading properties, and an a-tuple of positive integers (m(1), m(2),..., m(n)). We identify the algebras of supersymmetry, p = 2 parasupersymmetry, and fractional supersymmetry of order n with those of the Z(2)-graded TS of type (1, 1), Zz-graded TS of type (2, 1), and Z(n)-graded TS of type (1, 1,...,1), respectively. We also comment on the mathematical interpretation of the topological invariants associated with the Z(n)-graded TS of type (1, 1,...,1), For n = 2, the invariant is the Witten index which can be identified with the analytic index of a Fredholm operator. For n > 2, there are n independent integer-valued invariants. These can be related to differences of the dimension of the kernels of various products of n operators satisfying certain conditions. (C) 2001 Elsevier Science B.V
PRISM: a web server and repository for prediction of protein-protein interactions and modeling their 3D complexes
No full textThe PRISM web server enables fast and accurate prediction of protein-protein interactions (PPIs). The prediction algorithm is knowledge-based. It combines structural similarity and accounts for evolutionary conservation in the template interfaces. The predicted models are stored in its repository. Given two protein structures, PRISM will provide a structural model of their complex if a matching template interface is available. Users can download the complex structure, retrieve the interface residues and visualize the complex model
Looming losses in future time perception
No full textIt is proposed that a future time interval's perceived length will be affected by whether the interval ends with a gain or loss. Confirming this, several experiments indicate that consumers perceive intervals ending with losses as shorter than equivalent intervals ending with gains. The authors explore the mechanisms underlying these effects, and they identify several parallels between the current effects and loss aversion. The authors further show that these changes in time perception influence consumption decisions, and they consider the implications of the findings for theories of time perception and intertemporal choice
Application of pseudo-Hermitian quantum mechanics to a PT-symmetric Hamiltonian with a continuum of scattering states
No full textWe extend the application of the techniques developed within the framework of the pseudo-Hermitian quantum mechanics to study a unitary quantum system described by an imaginary PT-symmetric potential v(x) having a continuous real spectrum. For this potential that has recently been used, in the context of optical potentials, for modeling the propagation of electromagnetic waves traveling in a waveguide half and half filled with gain and absorbing media, we give a perturbative construction of the physical Hilbert space, observables, localized states, and the equivalent Hermitian Hamiltonian. Ignoring terms of order three or higher in the non-Hermiticity parameter zeta, we show that the equivalent Hermitian Hamiltonian has the form p(2)/2m+(zeta(2)/2)Sigma(infinity)(n=0){alpha(n)(x),p(2n)} with alpha(n)(x) vanishing outside an interval that is three times larger than the support of v(x), i.e., in 2/3 of the physical interaction region the potential v(x) vanishes identically. We provide a physical interpretation for this unusual behavior and comment on the classical limit of the system