Evolution of the European Political Community in Times of the EU’s ‘Geopolitical Awakening’

The latest developments on the global scene, notably Russia’s war on Ukraine, not only accelerated the European Union’s review of available measures to stabilise its neighbourhood, but also ignited a search for new forms of structuring relationships with its neighbours. With the inauguration of the European Political Community, the differentiation principle driving those relationships was enhanced. The new endeavour was not, however, conceived according to the blueprint, hence raising the crucial question about whether this was a relaunch of the EU position in its vicinity or a redundant layer added to the already complex reality of European foreign policy. Additionally, with the lack of even a simple written communiqué released after the summits, questions regarding its institutionalisation remain open

Cosmic ray driven dynamo in galactic disks. A parameter study

We present a parameter study of the magnetohydrodynamical dynamo driven by cosmic rays in the interstellar medium (ISM) focusing on the efficiency of magnetic field amplification and the issue of energy equipartition between magnetic, kinetic and cosmic ray (CR) energies. We perform numerical CR-MHD simulations of the ISM using the extended version of ZEUS-3D code in the shearing box approximation and taking into account the presence of Ohmic resistivity, tidal forces and vertical disk gravity. CRs are supplied in randomly distributed supernova (SN) remnants and are described by the diffusion-advection equation, which incorporates an anisotropic diffusion tensor. The azimuthal magnetic flux and total magnetic energy are amplified depending on a particular choice of model parameters. We find that the most favorable conditions for magnetic field amplification correspond to magnetic diffusivity of the order of 3\times 10^{25} \cm^2\s^{-1}, SN rates close to those observed in the Milky Way, periodic SN activity corresponding to spiral arms, and highly anisotropic and field-aligned CR diffusion. The rate of magnetic field amplification is relatively insensitive to the magnitude of SN rates in a rage of spanning 10% up to 100% of realistic values. The timescale of magnetic field amplification in the most favorable conditions is 150 Myr, at galactocentric radius equal to 5 kpc. The final magnetic field energies fluctuate near equipartition with the gas kinetic energy. In all models CR energy exceeds the equipartition values by a least an order of magnitude, in contrary to the expected equipartition. We suggest that the excess of cosmic rays can be attributed to the fact that the shearing-box does not permit cosmic rays to leave the system along the horizontal magnetic field.Comment: 12 papges, 11 figures, accepted for publication in Astronomy and Astrophysic

Reconnection Studies Under Different Types of Turbulence Driving

We study a model of fast magnetic reconnection in the presence of weak turbulence proposed by Lazarian and Vishniac (1999) using three-dimensional direct numerical simulations. The model has been already successfully tested in Kowal et al. (2009) confirming the dependencies of the reconnection speed $V_{rec}$ on the turbulence injection power $P_{inj}$ and the injection scale $l_{inj}$ expressed by a constraint $V_{rec} \sim P_{inj}^{1/2} l_{inj}^{3/4}$ and no observed dependency on Ohmic resistivity. In Kowal et al. (2009), in order to drive turbulence, we injected velocity fluctuations in Fourier space with frequencies concentrated around $k_{inj}=1/l_{inj}$, as described in Alvelius (1999). In this paper we extend our previous studies by comparing fast magnetic reconnection under different mechanisms of turbulence injection by introducing a new way of turbulence driving. The new method injects velocity or magnetic eddies with a specified amplitude and scale in random locations directly in real space. We provide exact relations between the eddy parameters and turbulent power and injection scale. We performed simulations with new forcing in order to study turbulent power and injection scale dependencies. The results show no discrepancy between models with two different methods of turbulence driving exposing the same scalings in both cases. This is in agreement with the Lazarian and Vishniac (1999) predictions. In addition, we performed a series of models with varying viscosity $\nu$. Although Lazarian and Vishniac (1999) do not provide any prediction for this dependence, we report a weak relation between the reconnection speed with viscosity, $V_{rec}\sim\nu^{-1/4}$.Comment: 19 pages, 9 figures. arXiv admin note: text overlap with arXiv:0903.205

National identity and stereotypes of Poles and Germans among rural youth in Opole Silesia

Abstract In Opole Silesia there live a combination of people describing themselves as Poles, Germans and Silesians. Young people there have to deal with that mix, being influenced by such forces as globalization. The purpose of this research was to discover how youth feel and understand their nationality and what stereotypes they share. The analysis consisted of several tasks. Students had to describe themselves by national and ethnic categories. They were asked how they felt about Germans and which stereotypes they found to be true or false. The paper includes analysis from earlier research on this topic

Z badań nad dyskursem szaradziarskim

The article constitutes an attempt to interpret a crossword as a text existing within the area of a charade discourse shaped over the centuries. In the first part devoted to terminological arrangements the author concentrates on distinguishing the contents of the notion of a discourse and text, as well as a dialogue text to proceed to their description in the category of the crossword further on. The subsequent theoretical considerations on the possibilities of using an interactive conception of sign and meaning in studies on the crossword precede the analysis of selected 20th century statements of the charade metadiscourse concerning the mechanisms of building an understanding between co‑authors of crossword texts

Cosmic-ray driven dynamo in the medium of irregular galaxy

We investigate the cosmic ray driven dynamo in the interstellar medium of irregular galaxy. The observations (Chyzy et al. 2000, 2003) show that the magnetic field in irregular galaxies is present and its value reaches the same level as in spiral galaxies. However the conditions in the medium of irregular galaxy are very unfavorable for amplification the magnetic field due to slow rotation and low shearing rate. In this work we present numerical model of the interstellar medium in irregular galaxies. The model includes magnetohydrodynamical dynamo driven by cosmic rays in the interstellar medium provided by random supernova explosions. We describe models characterized by different shear and rotation. We find that even slow galactic rotation with low shearing rate gives amplification of the magnetic field. Simulations have shown that high amount of the magnetic energy flow out off the simulation region becoming an efficient source of intergalactic magnetic fields.Comment: 2 pages, 2 figures, To be published in "Cosmic Magnetic Fields: From Planets, to Stars and Galaxies", K.G. Strassmeier, A.G. Kosovichev & J.E. Beckman, eds., Proc. IAU Symp. 259, CU

Evolution of the European Political Community in Times of the EU’s ‘Geopolitical Awakening’

The latest developments on the global scene, notably Russia’s war on Ukraine, not only accelerated the European Union’s review of available measures to stabilise its neighbourhood, but also ignited a search for new forms of structuring relationships with its neighbours. With the inauguration of the European Political Community, the differentiation principle driving those relationships was enhanced. The new endeavour was not, however, conceived according to the blueprint, hence raising the crucial question about whether this was a relaunch of the EU position in its vicinity or a redundant layer added to the already complex reality of European foreign policy. Additionally, with the lack of even a simple written communiqué released after the summits, questions regarding its institutionalisation remain open

Równoważenie rozwoju małego miasta w XXI wieku – ujęcie teoretyczne

The author, discussing the paradigm of sustainable development, refers it to the specificity of a small town. As a consequence, comparing distinctive factors influencing the development of a small town in a spirit of sustainable development, attempts to build a model of such a city, offering a tool for its controlling and monitoring in the form of a set of criteria. The article also attempts to answer two fundamental questions: first – what is the meaning of sustainable development, second – how the sustainable development of a small town differs from a broad sense of big city sustainable development?Autorka, omawiając paradygmat zrównoważonego rozwoju, odnosi go do specyfiki małego miasta. W konsekwencji, zestawiając charakterystyczne czynniki, mające wpływ na rozwój małego miasta w duchu zrównoważonego rozwoju, podejmuje próbę zbudowania modelu takiego miasta, proponując narzędzie do jego sterowania i monitorowania w postaci zestawu kryteriów do spełnienia. W artykule podjęto próbę odpowiedzi na dwa zasadnicze pytania badawcze: po pierwsze – co oznacza zrównoważony rozwój, po drugie – jak zrównoważony rozwój małego miasta różni się od ogólnie pojętego zrównoważonego rozwoju dużego miasta

3D MHD simulations of magnetic field evolution and radio polarization of barred galaxies

Aims. We study numerically the large-scale gas and magnetic field evolution of barred galaxies in the gravitational potential of a disk, bulge, halo, and bar. We solve non-linear MHD equations including the back-reaction of the magnetic field to the gas. We do not take into account any dynamo process. Methods. We apply the numerical MHD code to calculate the model of the galaxy in three dimensions. We construct realistic maps of high-frequency (Faraday rotation free) polarized radio emission on the basis of the simulated magnetic fields. The polarization model includes the effects of projection and limited resolution. Results. The main result is that our modeled polarization maps resemble the radio polarization structures observed in barred galaxies. The modeled polarization B-vectors distribution along the bar and between spiral arms resembles the observed topology of the magnetic field in barred galaxies. Our calculations for several different rotational velocities and sound speeds give the same result we got in our previous earlier published model. The reason of this behaviour is the dynamical evolution of the bar that causes gas to form spiral waves going radially outward. A gaseous spiral arms in turn generates magnetic ones, which live much longer in the inter-arm disk space than the gaseous pattern