Discreteness-induced resonances and AC voltage amplitudes in long one-dimensional Josephson junction arrays

New resonance steps are found in the experimental current-voltage characteristics of long, discrete, one-dimensional Josephson junction arrays with open boundaries and in an external magnetic field. The junctions are underdamped, connected in parallel, and DC biased. Numerical simulations based on the discrete sine-Gordon model are carried out, and show that the solutions on the steps are periodic trains of fluxons, phase-locked by a finite amplitude radiation. Power spectra of the voltages consist of a small number of harmonic peaks, which may be exploited for possible oscillator applications. The steps form a family that can be numbered by the harmonic content of the radiation, the first member corresponding to the Eck step. Discreteness of the arrays is shown to be essential for appearance of the higher order steps. We use a multi-mode extension of the harmonic balance analysis, and estimate the resonance frequencies, the AC voltage amplitudes, and the theoretical limit on the output power on the first two steps.Comment: REVTeX, 17 pages, 7 figures, psfig; to appear in J. Applied Physic

The combined impact of smoking, obesity and alcohol on life-expectancy trends in Europe

Background.- Smoking, obesity and alcohol abuse greatly affect mortality and exhibit a distinct time dynamic, with their prevalence and associated mortality rates increasing and (eventually) declining over time. Their combined impact on secular trends in life expectancy is unknown but is relevant for understanding these trends. We therefore estimate the combined impact of smoking, obesity and alcohol on life-expectancy trends in Europe. Methods.- We used estimated national age-specific smoking-, obesity- and alcohol-attributable mortality fractions for 30 European countries by sex, 1990-2014, which we aggregated multiplicatively to obtain lifestyle- attributable mortality. We estimated potential gains in life expectancy by eliminating lifestyle-attributable mortality and compared past trends in life expectancy at birth (e0) with and without lifestyle-attributable mortality. We examined all countries combined, by region and individually. Results.- Among men, the combined impact of smoking, obesity and alcohol on e0 declined from 6.6 years in 1990 to 5.8 years in 2014, mainly due to declining smoking attributable mortality. Among women, the combined impact increased from 1.9 to 2.3 years due to mortality increases in all three lifestyle-related factors. The observed increase in e0 over the 1990-2014 period was 5.0 years for men and 4.0 years for women. After excluding lifestyle-attributable mortality, this increase would have been 4.2-4.3 years for both men and women. Conclusion.- Without the combined impact of smoking, obesity and alcohol, the increase over time in life expectancy at birth would have been smaller among men but larger among women, resulting in a stable increase in e0, parallel for men and women

Studying stellar binary systems with the Laser Interferometer Space Antenna using Delayed Rejection Markov chain Monte Carlo methods

Bayesian analysis of LISA data sets based on Markov chain Monte Carlo methods has been shown to be a challenging problem, in part due to the complicated structure of the likelihood function consisting of several isolated local maxima that dramatically reduces the efficiency of the sampling techniques. Here we introduce a new fully Markovian algorithm, a Delayed Rejection Metropolis-Hastings Markov chain Monte Carlo method, to efficiently explore these kind of structures and we demonstrate its performance on selected LISA data sets containing a known number of stellar-mass binary signals embedded in Gaussian stationary noise.Comment: 12 pages, 4 figures, accepted in CQG (GWDAW-13 proceedings

Evaluasi Pengendalian Lalu Lintas dengan Lampu Pengatur Lalu Lintas pada Simpang Bersinyal

Permasalahan yang terjadi pada simpang bersinyal yang ada sekarang ini adalah banyak dijumpai antrian atau tundaan panjang, terutama pada saat jam – jam sibuk. Dilihat dari permasalahan yang ada, maka penelitian ini bertujuan untuk mengevaluasi pengendalian lalu lintas pada simpang bersinyal, sehingga diperoleh suatu solusi terbaik untuk mengurai permasalahan pada simpang bersinyal. Metode yang digunakan untuk mengevaluasi simpang bersinyal yang ada di Indonesia adalah metode MKJI 1997, dengan panjang antrian atau tundaan sebagai parameter kinerja simpang bersinyal. Metode tersebut bersifat general untuk semua kondisi simpang bersinyal yang ada di Indonesia. Apabila ditinjau dari kondisi existing lapangan, maka setiap simpang bersinyal memiliki karakteristik simpang, lalu lintas, land use, dan geometrik yang berbeda – beda. Salah satu simpang bersinyal yang dijadikan kajian wilayah studi adalah simpang Tlogosari – Semarang. Pada simpang tersebut sering dijumpai antrian panjang, baik pada hari kerja ( Senin – Jum\u27at ) maupun saat weekend ( Sabtu – Minggu ). Hasil analisis kinerja simpang bersinyal yang berupa panjang antrian dibandingkan dengan kondisi existing di lapangan, dengan menggunakan variabel - variabel yang berupa waktu siklus, fase dan arus jenuh. Apabila panjang antrian tidak sebanding dengan kondisi existing, maka perlu adanya revisi pada metode perhitungan simpang bersinyal yang disesuaikan dengan karakteristik simpang yang ada

Breathers in Josephson junction ladders: resonances and electromagnetic waves spectroscopy

We present a theoretical study of the resonant interaction between dynamical localized states (discrete breathers) and linear electromagnetic excitations (EEs) in Josephson junction ladders. By making use of direct numerical simulations we find that such an interaction manifests itself by resonant steps and various sharp switchings (voltage jumps) in the current-voltage characteristics. Moreover, the power of ac oscillations away from the breather center (the breather tail) displays singularities as the externally applied dc bias decreases. All these features can be mapped to the spectrum of EEs that has been derived analytically and numerically. Using an improved analysis of the breather tail, a spectroscopy of the EEs is developed. The nature of breather instability driven by localized EEs is established.Comment: 15 pages, 13 figure

Symmetry broken motion of a periodically driven Brownian particle: nonadiabatic regime

We report a theoretical study of an overdamped Brownian particle dynamics in the presence of both a spatially modulated one-dimensional periodic potential and a periodic alternating force (AF). As the periodic potential has a low symmetry (a ratchet potential) the Brownian particle displays a broken symmetry motion with a nonzero time average velocity. By making use of the Green function method and a mapping to the theory of Brillouin bands the probability distribution of the particle coordinate is derived and the nonlinear dependence of the macroscopic velocity on the frequency and the amplitude of AF is found. In particular, our theory allows to go beyond the adiabatic limit and to explain the peculiar reversal of the velocity sign found previously in the numerical analysis.Comment: 4 pages, 2 figure

Isoenzyme- and Allozyme-Specific Inhibitors: 2,20-Dihydroxybenzophenones and Their Carbonyl N-Analogues that Discriminate between Human Glutathione Transferase A1-1 and P1-1 Allozymes

The selectivity of certain benzophenones and their carbonyl N-analogues was investigated towards the human GSTP1-1 allozymes A, B and C involved in MDR. The allozymes were purified from extracts derived from E. coli harbouring the plasmids pEXP5-CT/TOPO-TAhGSTP1* A, pOXO4-hGSTP1*B or pOXO4-hGSTP1*C. Compound screening with each allozyme activity indicated three compounds with appreciable inhibitory potencies, 12 and 13 with P1-1A 62% and 67%, 11 and 12 with P1-1C 51% and 70%, whereas that of 15 fell behind with P1-1B (41%). These findings were confirmed by IC50 values (74–125 lM). Enzyme inhibition kinetics, aided by molecular modelling and docking, revealed that there is competition with the substrate CDNB for the same binding site on the allozyme (Ki(13/ A) = 63.6 +- 3.0 lM, K (15/B) = 198.6 +- 14.3 lM, and Ki(11/ C) = 16.5 +- 2.7 lM). These data were brought into context by an in silico structural comparative analysis of the targeted proteins. Although the screened compounds showed moderate inhibitory potency against hGSTP1-1, remarkably, some of them demonstrated absolute isoenzyme and/or allozyme selectivity

Synthesis and Study of 2‑(Pyrrolesulfonylmethyl)‑N‑arylimines: A New Class of Inhibitors for Human Glutathione Transferase A1‑1

Overexpression of human GSTA1-1 in tumor cells is part of MDR mechanisms. We report on the synthesis of 11 pyrrole derivatives as hGSTA1-1 inhibitors starting from 1-methyl-2-[(2-nitrobenzylsulfanyl]-1H-pyrrole. Molecular modeling revealed two locations in the enzyme H binding site: the catalytic primary one accommodating shorter and longer derivatives and the secondary one, where shorter derivatives can occupy. Derivative 9, displaying the highest inhibition and bearing a p-nitroarylimino moiety, and derivative 4, lacking this moiety, were studied kinetically. Derivative 9 binds (Ki(9) = 71 ± 4 μM) at the primary site competitively vs CDNB. Derivative 4 binds (Ki(4) = 135 ± 27 μM) at the primary and secondary sites, allowing the binding of a second molecule (4 or CDNB) leading to formation of unreactive and reactive complexes, respectively. The arylmethylsulfonylpyrrole core structure is a new pharmacophore for hGSTA1-1, whereas its derivative 9 may serve as a lead structure

A symmetry-preserving second-order time-accurate PISO-based method

A new conservative symmetry-preserving second-order time-accurate PISO-based pressure-velocity coupling for solving the incompressible Navier-Stokes equations on unstructured collocated grids is presented in this paper. This new method for implicit time stepping is an extension of the conservative symmetry-preserving incremental-pressure projection method for explicit time stepping and unstructured collocated meshes of Trias et al. [35]. In order to assess and compare both methods, we have implemented them within one unified solver in the open source code OpenFOAM where we use a Butcher array to prescribe the Runge-Kutta method. Thus, by changing the entries of the Butcher array, explicit and diagonally implicit Runge-Kutta schemes can be combined into one solver. We assess the energy conservation properties of the implemented discretisation methods and the temporal consistency of the selected Runge-Kutta schemes using Taylor-Green vortex and lid-driven cavity flow test cases. Finally, we use a more complex turbulent channel flow test case in order to further assess the performance of the presented new conservative symmetry-preserving incremental-pressure PISO-based method. Although both implemented methods are based on a symmetry-preserving discretisation, we show they still produce a small amount of numerical dissipation when the total pressure is directly solved from a Poisson equation. When an incremental-pressure approach is used, where a pressure correction is solved from a Poisson equation, both methods are effectively fully-conservative. For high-fidelity simulations of incompressible turbulent flows, it is highly desirable to use fully-conservative methods. For such simulations, the presented numerical methods are therefore expected to have large added value, since they pave the way for the execution of truly energy-conservative high-fidelity simulations in complex geometries. Furthermore, both methods are implemented in OpenFOAM, which is widely used within the CFD community, so that a large part of this community can benefit from the developed and implemented numerical methods