Large-scale Ferrofluid Simulations on Graphics Processing Units

We present an approach to molecular-dynamics simulations of ferrofluids on graphics processing units (GPUs). Our numerical scheme is based on a GPU-oriented modification of the Barnes-Hut (BH) algorithm designed to increase the parallelism of computations. For an ensemble consisting of one million of ferromagnetic particles, the performance of the proposed algorithm on a Tesla M2050 GPU demonstrated a computational-time speed-up of four order of magnitude compared to the performance of the sequential All-Pairs (AP) algorithm on a single-core CPU, and two order of magnitude compared to the performance of the optimized AP algorithm on the GPU. The accuracy of the scheme is corroborated by comparing the results of numerical simulations with theoretical predictions

On factorization hierarchy of equations for banana Feynman amplitudes

We present a review of the relations between various equations for maximal cut banana Feynman diagrams, i.e. amplitudes with propagators substituted with $\delta$-functions. We consider both equal and generic masses. There are three types of equation to consider: those in coordinate space, their Fourier transform and Picard-Fuchs equations originating from the parametric representation. First, we review the properties of the corresponding differential operators themselves, mainly their factorization properties at the equal mass locus and their form at special values of the dimension. Then we study the relation between the Fourier transform of the coordinate space equations and the Picard-Fuchs equations and show that they are related by factorization as well. The equations in question are the counterparts of the Virasoro constraints in the much-better studied theory of eigenvalue matrix models and are the first step towards building a full-fledged theory of Feynman integrals, which will reveal their hidden integrable structure.Comment: 13 page

The state and prospects of development of national higher pharmaseutical education

The paper considers the materials of the Pharmacists Summit and International Pharmaceutical Congresses, in particular, the issue of achieving quality pharmaceutical education. It shows cause of the proper training process of pharmacy sector specialists in accordance with current state and requirements of the society and suggests a model of professional pharmaceutical education. According to the authors of the paper, the implementation of education quality in Ukraine calls for, first, professionally educated personnel in the pharmacy sector of healthcare; second, proper academic and university infrastructure for training future specialists within the system of higher pharmaceutical education; third, ensuring the high quality of higher pharmaceutical education on the basis of implementing the competence approach and taking into account international experience on pharmacy development. Increasing significance of the pharmacy branch in Ukraine is directly linked to the quality of training of pharmacy specialists, continuous improvement of the content of their education, implementation of new educational technologies, adapting higher pharmaceutical education to European standards. According to the authors, an important condition of ensuring effective professional training of future pharmacy specialists within the national system of higher pharmaceutical education is the following: firstly, considering public demand to the level of healthcare services, disease prevention; secondly, implementing the productive global experience on introducing customer service standards. The established prospects of the development of national higher pharmaceutical education include: 1) the adoption of ethical principles of training Masters of Pharmacy within the system of higher pharmaceutical education; 2) focus on European pharmacy standards which are based on high customer service standards; 3) improvement of the content of pharmacy specialist education taking into account the development of national pharmaceutical production; 4) ensuring the development of the clinical direction within the system of general pharmacist training

Nonlinear evolution of short-wavelength torsional Alfvén waves

We analyze nonlinear evolution of torsional Alfvén waves in a straight magnetic flux tube filled in with a low-β plasma, and surrounded with a plasma of lower density. Such magnetic tubes model, in particular, a segment of a coronal loop or a polar plume. The wavelength is taken comparable to the tube radius. We perform a numerical simulation of the wave propagation using ideal magnetohydrodynamics. We find that a torsional wave nonlinearly induces three kinds of compressive flows: the parallel flow at the Alfvén speed, which constitutes a bulk plasma motion along the magnetic field, the tube wave, and also transverse flows in the radial direction, associated with sausage fast magnetoacoustic modes. In addition, the nonlinear torsional wave steepens and its propagation speed increases. The latter effect leads to the progressive distortion of the torsional wave front, i.e., nonlinear phase mixing. Because of the intrinsic non-uniformity of the torsional wave amplitude across the tube radius, the nonlinear effects are more pronounced in regions with higher wave amplitudes. They are always absent at the axes of the flux tube. In the case of a linear radial profile of the wave amplitude, the nonlinear effects are localized in an annulus region near the tube boundary. Thus, the parallel compressive flows driven by torsional Alfvén waves in the solar and stellar coronae, are essentially non-uniform in the perpendicular direction. The presence of additional sinks for the wave energy reduces the efficiency of the nonlinear parallel cascade in torsional Alfvén waves