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Förster Resonance Energy Transfer Calculator (FRET−Calc) is a program and web server that analyzes molar extinction coefficient of the acceptor, emission spectrum of the donor, and the refractive index spectrum of the donor/acceptor blend. Its main function is to obtain important parameters of the FRET process from experimental data, such as: (i) effective refractive index, (ii) overlap integral, (iii) Förster radius, (iii) FRET efficiency and (iv) FRET rate. FRET−Calc is license free software that can be run via dedicated web server (nanocalc.org) or downloading the program executables (for Unix , Windows , and macOS) from the FRET−Calc repository on GitHub. The program features a user−friendly interface, making it suitable for materials research and teaching purposes. In addition, the program is optimized to run on normal computers and is lightweight. An example will be given with the step by step of its use and results obtained. • FRET parameters from experimental data to study organic materials such as polymers, fullerenes, non-fullerenes and dyes. • Simple and intuitive graphic interface for the FRET rate acquisition. • Possibility of use on your own computer or online. [ABSTRACT FROM AUTHOR]

In this study the coupled overlapping domain (COD) technique, previously developed within our group, is extended to make it suitable for fluid–structure interaction (FSI) computations with flexible elastic solids. A standard FSI benchmark from literature is implemented to verify the computations of the COD technique. However, in this study the incompressible neo-Hookean material model is applied instead of the compressible St. Venant-Kirchhoff model. The results of the COD technique are compared to the solutions obtained with a full finite element method. The performed computations demonstrate the COD technique accurately computes the solids displacements and the forces on the elastic solid. The results of the COD technique also show a good resemblance with the results obtained by other researchers, even with the use of a different material model. Additionally, the COD technique is applied to compute a rotating elastic beam in a square box filled with fluid. The computations show that the COD technique is capable of computing large deformations and translations, which makes this technique suitable for a wide range of applications without the need for computationally expensive remeshing. [ABSTRACT FROM AUTHOR]

We consider coupled weakly birefringent cavities filled-in with nonlinear Kerr material and subject to linearly polarized optical injection. Light propagation in such a system is described by a system of discrete Lugiato–Lefever-type equations for each linear polarization component of the electric field into each cavity, coupled by the cross-phase modulation terms and the neighboring waveguides field overlap integrals. We demonstrate that this system supports stable three-dimensional vector localized structures often called discrete vector light bullets. We consider both anomalous and normal dispersion and show that it results in the generation of, respectively, bright and dark discrete vector light bullets. Due to the polarization multistability of the system, we demonstrated coexisting light bullets with polarization at the light bullets peaks as different as predominantly linear to predominantly circular. We have shown that chaotic spatio-temporal dynamics can be realized even for such an injection strengths for which the light bullets distribution in the system is stationary by increasing the coupling strength C between the cavities. [ABSTRACT FROM AUTHOR]

Abstract: We study self-similar measures defined by non-uniformly contractive iterated function systems of similitudes with overlaps. In the case the contraction ratios of the similitudes are exponentially commensurable, we describe a method to compute the L 2-dimension of the associated self-similar measures. Our result allows us to determine the singularity of some of such measures. [Copyright &y& Elsevier]

We find the allowed complex overlaps for N equidistant pure quantum states. The accessible overlaps define a petal-shaped area on the Argand plane. Each point inside the petal represents a set of N linearly independent pure states and each point on its contour represents a set of N linearly dependent pure states. We find the optimal probabilities of success of discriminating unambiguously in which of the N equidistant states the system is. We show that the phase of the involved overlap plays an important role in the probability of success. For a fixed overlap modulus, the success probability is highest for the set of states with an overlap with phase equal to zero. In this case, if the process fails, then the information about the prepared state is lost. For states with a phase different from zero, the information could be obtained with an error-minimizing measurement protocol. [ABSTRACT FROM AUTHOR]

In Part 1 of this two-part series, John Hinshaw discussed the resolution of a pair of symmetrical peaks and the effects that relative peak size have on area measurements. This month's "GC Connections" examines the effects of peak tailing on resolution and peak overlap. [ABSTRACT FROM AUTHOR]

Triply heavy baryons are investigated in the framework of the relativistic quark model based on the quark-diquark picture in the quasipotential approach in QCD. Masses of the ground and excited states of the Ωccc, Ωbbb, Ωccb, and Ωcbb baryons are calculated. Orbital and radial excitations between the diquark and quark as well as between quarks inside the diquark are considered. The diquark internal structure is consistently taken into account by the form factor of the diquark-gluon interaction expressed through the overlap integral of the diquark wave functions. A detailed comparison with previous calculations is given. [ABSTRACT FROM AUTHOR]

In this work, the Gaussian Network Model (GNM) and Anisotropic Network Model (ANM) approaches are applied to describe the dynamics of Pancreatic Trypsin Inhibitor protein graphs built from smoothed promolecular electron density (ED) distribution functions. A specific smoothing degree is selected which provides a clear partitioning of the protein structure into fragments located either on the protein backbone or side chains. A first set of analyses is carried out on results obtained from ED maxima calculated at that specific smoothing level. A second set is achieved for a protein ED network whose edges are weighted by ED overlap integral values. Results are compared with those obtained through GNM, ANM, and Normal Mode Analysis approaches, applied to the network of atoms. [Copyright &y& Elsevier]

Abstract: The paper presents a semi-analytical method for solving the problem of two joined, dissimilar isotropic elastic half-planes, one of which contains a large number of arbitrary located, non-overlapping, perfectly bonded circular elastic inhomogeneities. In general, the inhomogeneities may have different elastic properties and sizes. The analysis is based on a solution of a complex singular integral equation with the unknown tractions at each circular boundary approximated by a truncated complex Fourier series. A system of linear algebraic equations is obtained by using a Taylor series expansion. Apart from round-off, the only errors introduced into the solution are due to truncation of the Fourier series. The resulting semi-analytical method allows one to calculate the elastic fields everywhere in the half-planes and inside the inhomogeneities. Numerical examples are included to demonstrate the effectiveness of the approach. [Copyright &y& Elsevier]

We discuss the localization of eigenmodes of the covariant lattice Laplacian and overlap Dirac operator in lattice SU(2) gluodynamics. It occurs that the localization properties of the eigenmodes for fundamental scalars and fermions are different in confining configurations and in those from which confining disorder was eliminated by center-vortex removal. Localization of eigenmodes on subspaces of dimension less than four indicates the existence of the low dimensional structures in the confining vacuum. [Copyright &y& Elsevier]

I present results for the mass spectrum of excited baryons and pentaquarks using overlap fermions and Bayesian curve-fitting method; and magnetic moments and polarizabilities for a variety of hadrons in the background field method. [Copyright &y& Elsevier]

Some key features of the overlap operator with a UV-filtered Wilson kernel are discussed. The first part concerns spectral properties of the underlying shifted hermitean Wilson operator and the relation to the observed speedup of the overlap construction. Next, the localization of the filtered overlap and its axial-vector renormalization constant are discussed. Finally, results of an exploratory scaling study for m ud , m s and f π , f K are presented. [Copyright &y& Elsevier]

We discuss the adaptation of the Hybrid Monte Carlo algorithm to overlap fermions. We derive a method which can be used to account for the delta function in the fermionic force caused by the differential of the sign function. We discuss the algoritmic difficulties that have been overcome, and mention those that still need to be solved. [Copyright &y& Elsevier]

In this work, we discuss exclusive semileptonic Bc-meson decays: Bc→ηc(J/ψ)lν and Bc→D(D∗)lν in the framework of the relativistic independent quark (RIQ) model based on an average flavor independent confining potential in equally mixed scalar-vector harmonic form. We calculate the invariant form factors representing decay amplitudes from the overlapping integrals of meson wave functions derivable in the RIQ model. To evaluate the lepton mass effects in the semileptonic decays, we first study the q²-dependence of the form factors in the accessible kinematic range of q² involved in the decay process in its e- and τ- mode separately. Similar studies on helicity amplitudes, q²--spectra for different helicity contributions, and total q²-spectra for each decay process are carried out separately in their e- and τ- modes. We predict the decay rates/branching fractions, forward-backward asymmetry, and the asymmetry parameter in reasonable agreement with other model predictions, which can hopefully be tested in future experiments at the Tevatron and LHC. We also predict the observable ′R′ which corresponds to the ratio of branching fractions for the decay process in its e- mode to its corresponding value in the τ- mode. Our results are comparable to other standard model(SM) predictions which highlight the failure of the lepton flavor universality hinting at new physics beyond SM for the explanation of the observed deviation of observable ′R′ value from the corresponding SM predictions. [ABSTRACT FROM AUTHOR]

We examine the inertial modes of vibration of a Maclaurin spheroid and determine how they are driven by an external tidal field, either Newtonian (gravitoelectric) or post-Newtonian (gravitomagnetic). The context and motivation for this work come from the realization that inertial modes of rotating neutron stars can be resonantly excited in binary inspirals, with a measurable effect on the phasing of the emitted gravitational waves. We aim to provide additional insights into this phenomenon. We calculate how the frequencies of the relevant inertial modes, and their overlap integrals with the tidal forces, vary as the star's rotation rate increases, spanning almost the full range between zero rotation and the mass-shedding limit. We prove that a single inertial mode couples to a Newtonian tidal field; overlap integrals with all other modes vanish. We prove also that four inertial modes couple to a post-Newtonian, gravitomagnetic tidal field; overlap integrals with all other modes vanish. Finally, we determine the rather extreme conditions under which the gravitoelectric driving of inertial modes dominates over the gravitomagnetic driving. [ABSTRACT FROM AUTHOR]

We develop a FORTRAN code to compute fluctuations in atomic condensates (FACt) by solving the Bogoliubov–de Gennes (BdG) equations for two component Bose–Einstein condensate (TBEC) in quasi-two dimensions. The BdG equations are recast as matrix equations and solved self consistently. The code is suitable for handling quantum fluctuations as well as thermal fluctuations at temperatures below the critical point of Bose–Einstein condensation. The code is versatile, and the ground state density profile and low energy excitation modes obtained from the code can be easily adapted to compute different properties of TBECs — ground state energy, overlap integral, quasi particle amplitudes of BdG spectrum, dispersion relation and structure factor and other related experimental observables. Program Title: FACt Program Files doi: http://dx.doi.org/10.17632/5h348ndydg.1 Licensing provisions: MIT Programming language: FORTRAN 90 External routines/libraries: ARPACK Nature of problem: Compute the ground state density profile, ground state energy and chemical potential for individual species, evaluate the quasiparticle mode energies and corresponding amplitudes which can capture the transformation of the modes against the change of the parameters (intraspecies interaction, interspecies interaction, anisotropy parameter etc.) using Hartree–Fock–Bogoliubov theory with the Popov approximation. Calculate the overlap integral, dispersion relation and structure factor. Solution method: In the first step, the pair of coupled Gross–Pitaevskii equations (CGPEs) is solved using split time-step Fourier pseudospectral method to compute the condensate density. To solve the BdG equations, as a basic input the first N b harmonic oscillator eigenstates are chosen as a basis to generate the BdG 011 matrix with dimension of 4 (N b + 1) × 4 (N b + 1). Since the matrix size rapidly increases with N b , Arpack routines are used to diagonalize the BdG matrix efficiently. To compute the fluctuation and non-condensate density, a set of the low energy quasiparticle amplitudes above a threshold value of the Bose factor are considered. The equations are then solved iteratively till the condensate, and non-condensate densities converge to predefined accuracies. To accelerate the convergence we use the method of successive under-relaxation (SUR). Additional comments including restrictions and unusual features: For a large system size, if the harmonic oscillator basis size is also taken to be large, the dimension of the BdG matrix becomes huge. It may take several days to compute the low energy modes at finite temperature and this package may be computationally expensive. After successful computation of this package, one should obtain the equilibrium density profiles for TBEC, low energy Bogoliubov modes and the corresponding quasiparticle amplitudes. In addition, one can calculate the dispersion relation, structure factor, overlap integral, correlation function, etc. using this package with minimal modifications. In the theory section of the manuscript, we have provided the expressions to compute the above quantities numerically. [ABSTRACT FROM AUTHOR]

The form factors parametrizing the weak D and Ds transitions to light pseudoscalar and vector mesons are calculated in the framework of the relativistic quark model based on the quasipotential approach. The special attention is paid to the systematic account of the relativistic effects including transformation of the meson wave function from the rest to moving reference frame and contributions of the intermediate negative-energy states. The form factors are expressed through the overlap integrals of the meson wave functions, which are taken from previous studies of meson spectroscopy. They are calculated in the whole range of the transferred momentum q². Convenient parametrization of the form factors which accurately reproduces numerical results is given. The obtained values of the form factors and their ratios at q² = 0 agree well with the ones extracted form the experimental data. On the basis of these form factors and helicity formalism, differential and total semileptonic decay rates of D and Ds mesons as well as different asymmetries and polarization parameters are calculated. The detailed comparison of the obtained results with other theoretical calculations and experimental data is given. [ABSTRACT FROM AUTHOR]

We present relaxation and preconditioning techniques which accelerate the inversion of the overlap operator by a factor of four on small lattices, with larger gains as the lattice size increases. These improvements can be used in both propagator calculations and dynamical simulations. [Copyright &y& Elsevier]

The article discusses the motion of asymmetrical overlaps in hydraulics. It cites benefits of setting overlaps at individual valves. It presents a figure showing valve coefficients as a result of input data. It examines flow and leakage metering characteristics of the valve which has asymmetrical laps on four lands.