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Number of results: 38
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Abstract

Confronted with a natural tendency of marginalization national/ethnic minorities and immigrant communities respond by adopting two diverse strategies of showing their presence in the public sphere of the host country. Depending on the level of their integration and the goals they want to achieve, they can either stress their links (affinity) with the majority culture or the differences that mark them out. However, some minority communities succeed in achieving a distinctive presence in the public sphere already at the stage of launching its own media.
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Abstract

Samoregulacja mediów może mieć istotny wpływ na kształtowanie się kultury dziennikarskiej i poziomu etycznego mediów. Jej skuteczność jest jednak uzależniona od stopnia instytucjonalizacji narzędzi samoregulacyjnych i ich powszechnej akceptacji. Różny jest ten poziom w różnych systemach medialnych, co często warunkowane jest historycznie. Artykuł za cel przyjmuje prezentację historycznego rozwoju samoregulacji trzech systemów medialnych (francuskiego, brytyjskiego i fińskiego) wpisujących się w trzy różne modele systemów medialnych opisane przez Daniela Hallina i Paolo Manciniego i zestawienie ich z rozwojem samoregulacji mediów w Polsce.
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Keywords media nostalgia

Abstract

Prof. Andreas Böhn, a fellow of the Polish Institute of Advanced Studies (PIASt), explains why we love Polaroids and wonders if our refrigerators will be soon buying milk for us.
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Abstract

Research on participation of social media users has contributed to our understanding of modern citizenship, civic engagement, and contemporary public sphere. Despite a growing interest in participatory practices in social media little is known about the factors affecting political participation of social media users. Based on an online survey of 700 social media users in Poland, this study examines the relationship between social capital (defined at the individual level as a resource embedded in personal networks) and political participation. It has been established that there is a contradictory relationship between social capital and participatory activities of social media users. Apparently, differences between the resources that are only embedded in personal networks on the one hand, and those that can be mobilized for purposive actions on the other, matter when association between social capital and political participation is considered. Moreover, the presence of these resources significantly varies across different types of social relations (family, friends and acquaintances) of respondents engaged in different participatory actions.
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Abstract

Standing waves and acoustic heating in a one-dimensional resonator filled with chemically reacting gas, is the subject of investigation. The chemical reaction of A → B type, which takes place in a gas, may be reversible or not. Governing equations for the sound and entropy mode which is generated in the field of sound are derived by use of a special mathematical method. Under some conditions, sound waves propagating in opposite directions do not interact. The character of nonlinear dynamics of the sound and relative acoustic heating or cooling depends on reversibility of a chemical reaction. Some examples of acoustic heating in a resonator are illustrated and discussed.
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Abstract

Heat flow in heterogeneous media with complex microstructure follows tortuous path and therefore determination of temperature distribution in them is a challenging task. Two-scales, micro-macro model of heat conduction with phase change in such media was considered in the paper. A relation between temperature distribution on the microscopic level, i.e., on the level of details of microstructure, and the temperature distribution on the macroscopic level, i.e., on the level where the properties were homogenized and treated as effective, was derived. The expansion applied to this relation allowed to obtain its more simplified, approximate form corresponding to separation of micro- and macro-scales. Then the validity of this model was checked by performing calculations for 2D microstructure of a composite made of two constituents. The range of application of the proposed micro-macro model was considered in transient states of heat conduction both for the case when the phase change in the material is present and when it is absent. Variation of the effective thermal conductivity with time was considered and a criterion was found for which application of the considered model is justified.
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Abstract

An original model based on first principles is constructed for the temporal correlation of acoustic waves propagating in random scattering media. The model describes the dynamics of wave fields in a previously unexplored, moderately strong (mesoscopic) scattering regime, intermediate between those of weak scattering, on the one hand, and diffusing waves, on the other. It is shown that by considering the wave vector as a free parameter that can vary at will, one can provide an additional dimension to the data, resulting in a tomographic-type reconstruction of the full space-time dynamics of a complex structure, instead of a plain spectroscopic technique. In Fourier space, the problem is reduced to a spherical mean transform defined for a family of spheres containing the origin, and therefore is easily invertible. The results may be useful in probing the statistical structure of various random media with both spatial and temporal resolution.
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Abstract

Dążenie do zmierzenia i przetłumaczenia otaczającej rzeczywistości na dający się przetwarzać komputerowo cyfrowy język stało się dominującym motywem współczesnej fazy kapitalizmu. Ma to konsekwencje dla sposobu postrzegania ludzkiego ciała. Stawiam tezę, że wraz z rozwojem technologii ubieralnych staje się ono obszarem kapitalistycznej eksploatacji. Dane, pozyskiwane dzięki urządzeniom ubieralnym bezpośrednio z ciała, mogą być wykorzystywane do zarządzania nim. W tym artykule tendencja do mierzenia wszelkich aspektów własnego życia i zachodzących w ciele procesów, wraz z towarzyszącym jej przekonaniem, że poddają się one ilościowym określeniom, nazwana będzie wydobywaniem danych z samego siebie. Artykuł ma na celu prześledzenie ideologicznych przesłanek warunkujących funkcjonowanie technologii ubieralnych, a także naświetlenie jak konkretne przekonania i regulatywne koncepcje ich dotyczące zostały wplecione w materię codzienności i poddane naturalizacji.
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Abstract

Pluralistyczny dostęp poszczególnych partii i środowisk politycznych do mediów uznawany jest za jeden z fundamentów demokracji. Odwołując się do danych dotyczących obecności polityków w najważniejszych telewizyjnych i radiowych programach publicystycznych oraz danych dotyczących rynkowego zasięgu poszczególnych nadawców, artykuł analizuje wpływ, jaki poszczególne środowiska polityczne miały na polską medialną sferę publiczną w okresie od listopada 2015 do grudnia 2017 roku. Artykuł zmierza w stronę opisu normatywnego, dostarczającego odpowiedzi na pytanie, czy i w jakim stopniu poszczególne partie polityczne są nad- lub niedoreprezentowane w medialnej sferze publicznej. Odpowiedź umożliwia zestawienie uzyskanych danych z liberalno-przedstawicielskim modelem sfery publicznej we współczesnych demokracjach (Ferree, Gamson, Gerhards i Rucht 2002). Autorzy wnioskują, że polska sfera publiczna mieści się w demokratycznych standardach wyznaczonych przez przyjęte do analizy modele, choć zarówno nadawcy publiczni jak i prywatni mają problemy z zachowaniem odpowiedniego poziomu reprezentatywności różnych partii w swoich stacjach.
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Abstract

Aerosol filtration in fibrous filters is one of the principal methods of accurate removal of particulate matter from a stream of gas. The classical theory of depth filtration of aerosol particles in fibrous structures is based on the assumption of existing single fibre efficiency, which may be used to recalculate the overall efficiency of entire filter. Using “classical theory” of filtration one may introduce some errors, leading finally to a discrepancy between theory and experiment. There are several reasons for inappropriate estimation of the single fibre efficiency: i) neglecting of shortrange interactions, ii) separation of inertial and Brownian effects, ii) perfect adhesion of particles to the fibre, iv) assumption of perfect mixing of aerosol particles in the gas stream, v) assumption of negligible effect of the presence of neighbouring fibres and vi) assumption of perpendicular orientation of homogenous fibres in the filtration structure. Generally speaking, “classical theory” of filtration was used for characterization of the steady - state filtration process (filtration in a clean filter, at the beginning of the process) without deeper investigation of the influence of the nternal structure of the filter on its performance. The aim of this review is to outline and discuss the progress of deep-bed filtration modelling from the use of simple empirical correlations to advanced techniques of Computational Fluid Dynamics and Digital Fluid Dynamics.
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Abstract

Dynamics of a weakly nonlinear and weakly dispersive flow of a gas where molecular vibrational relaxation takes place is studied. Variations in the vibrational energy in the field of intense sound is considered. These variations are caused by a nonlinear transfer of the acoustic energy into energy of vibrational degrees of freedom in a relaxing gas. The final dynamic equation which describes this is instantaneous, it includes a quadratic nonlinear acoustic source reflecting the nonlinear character of interaction of high-frequency acoustic and non-acoustic motions in a gas. All types of sound, periodic or aperiodic, may serve as an acoustic source. Some conclusions about temporal behavior of the vibrational mode caused by periodic and aperiodic sounds are made.
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Abstract

Deep bed filtration is an effective method of submicron and micron particle removal from the fluid stream. There is an extensive body of literature regarding particle deposition in filters, often using the classical continuum approach. However, the approach is not convenient for studying the influence of particle deposition on filter performance (filtration efficiency, pressure drop) when non-steady state boundary conditions have to be introduced. For the purposes of this work the lattice-Boltzmann model describes fluid dynamics, while the solid particle motion is modeled by the Brownian dynamics. For aggregates the effect of their structure on displacement is taken into account. The possibility of particles rebound from the surface of collector or reentrainment of deposits to fluid stream is calculated by energy balanced oscillatory model derived from adhesion theory. The results show the evolution of filtration efficiency and pressure drop of filters with different internal structure described by the size of pores. The size of resuspended aggregates and volume distribution of deposits in filter were also analyzed. The model enables prediction of dynamic filter behavior. It can be a very useful tool for designing filter structures which optimize maximum lifetime with the acceptable values of filtration efficiency and pressure drop.
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Abstract

Diagnostics and decomposition of atmospheric disturbances in a planar flow are considered in this work. The study examines a situation in which the stationary equilibrium temperature of a gas may depend on the vertical coordinate due to external forces. The relations connecting perturbations are analytically established. These perturbations specify acoustic and entropy modes in an arbitrary stratified gas affected by a constant mass force. The diagnostic relations link acoustic and entropy modes, and are independent of time. Hence, they provide an ability to decompose the total vector of perturbations into acoustic and non-acoustic (entropy) parts, and to establish the distribution of energy between the sound and entropy modes, uniquely at any instant. The total energy of a flow is hence determined in its parts which are connected with acoustic and entropy modes. The examples presented in this work consider the equilibrium temperature of a gas, which linearly depends on the vertical coordinate. Individual profiles of acoustic and entropy parts for some impulses are illustrated with plots.
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Abstract

In many therapeutic applications of a pulsed focused ultrasound with various intensities the finite- amplitude acoustic waves propagate in water before penetrating into tissues and their local heating. Water is used as the matching, cooling and harmonics generating medium. In order to design ultrasonic probes for various therapeutic applications based on the local tissue heating induced in selected organs as well as to plan ultrasonic regimes of treatment a knowledge of pressure variations in pulsed focused nonlinear acoustic beams produced in layered media is necessary. The main objective of this work was to verify experimentally the applicability of the recently developed numerical model based on the Time- Averaged Wave Envelope (TAWE) approach (Wójcik et al., 2006) as an effective research tool for predicting the pulsed focused nonlinear fields produced in two-layer media comprising of water and tested materials (with attenuation arbitrarily dependent on frequency) by clinically relevant axially-symmetric therapeutic sources. First, the model was verified in water as a reference medium with known linear and nonlinear acoustic properties. The measurements in water were carried out at a 25◦C temperature using a 2.25 MHz circular focused (f/3.0) transducer with an effective diameter of 29 mm. The measurement results obtained for 8-cycle tone bursts with three different initial pressure amplitudes varied between 37 kPa and 113 kPa were compared with the numerical predictions obtained for the source boundary condition parameters determined experimentally. The comparison of the experimental results with those simulated numerically has shown that the model based on the TAWE approach predicts well both the spatial-peak and spatial-spectral pressure variations in the pulsed focused nonlinear beams produced by the transducer used in water for all excitation levels complying with the condition corresponding to weak or moderate source-pressure levels. Quantitative analysis of the simulated nonlinear beams from circular transducers with ka ≫ 1 allowed to show that the axial distance at which sudden accretion of the 2nd or higher harmonics amplitude appears is specific for this transducer regardless of the excitation level providing weak to moderate nonlinear fields. For the transducer used, the axial distance at which the 2nd harmonics amplitude suddenly begins to grow was found to be equal to 60 mm. Then, the model was verified experimentally for two-layer parallel media comprising of a 60-mm water layer and a 60-mm layer of 1.3-butanediol (99%, Sigma-Aldrich Chemie GmbH, Steinheim, Germany). This medium was selected because of its tissue-mimicking acoustic properties and known nonlinearity parameter B/A. The measurements of both, the peak- and harmonic-pressure variations in the pulsed nonlinear acoustic beams produced in two-layer media (water/1.3-butanediol) were performed for the same source boundary conditions as in water. The measurement results were compared with those simulated numerically. The good agreement between the measured data and numerical calculations has shown that the model based on the TAWE approach is well suited to predict both the peak and harmonic pressure variations in the pulsed focused nonlinear sound beams produced in layered media by clinically relevant therapeutic sources. Finally, the pulsed focused nonlinear fields from the transducer used in two-layer media: water/castor oil, water/silicone oil (Dow Corning Ltd., Coventry, UK), water/human brain and water/pig liver were predicted for various values of the nonlinearity parameter of tested media.
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Abstract

Weakly nonlinear sound propagation in a gas where molecular vibrational relaxation takes place is studied. New equations which govern the sound in media where the irreversible relaxation may take place are derived and discussed. Their form depends on the regime of excitation of oscillatory degrees of freedom, equilibrium (reversible) or non-equilibrium (irreversible), and on the comparative frequency of the sound in relation to the inverse time of relaxation. Additional nonlinear terms increase standard nonlinearity of the high-frequency sound in the equilibrium regime of vibrational excitation and decrease otherwise. As for the nonlinearity of the low-frequency sound, the conclusions are opposite. Appearance of a non-oscillating additional part which is a linear function of the distance from the transducer is an unusual property of nonlinear distortions of harmonic at the transducer high-frequency sound
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Abstract

In 2019 the Polish Jazz Association will celebrate its 50th anniversary. Its activities over that period were accompanied by countless publications in the following categories: 1) regular periodicals; 2) mimeographed typescripts and bulletins; 3) festival programmes and graphics; 4) others (flyers, ephemera, posters). The aim of this article is to examine the mechanisms of PJA publicizing its activities and using media to reach out to the jazz fan community
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Abstract

The growing number of mobile devices and the increasing popularity of multimedia services result in a new challenge of providing mobility in access networks. The paper describes experimental research on media (audio and video) streaming in a mobile IEEE 802.11 b/g/n environment realizing network-based mobility. It is an approach to mobility that requires little or no modification of the mobile terminal. Assessment of relevant parameters has been conducted in an IPv6 testbed. During the tests, both Quality of Service (QoS) and Quality of Experience (QoE) parameters have been considered. Against the background of standard L3 and L2 handovers, an emerging mobility solution named Proxy Mobile IPv6 (PMIPv6) has been examined. Its advantages (L3 connectivity maintenance) and disadvantages (packet loss during handover) are emphasized based on the obtained results. Moreover, a new solution for handover optimization has been proposed. A handoff influence upon audio/video generation and transfer imperfections has been studied and found to be an interesting direction of future work.
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Abstract

This project aimed to isolate and characterize volcanic soil Actinobacteria from Deception Island, Antarctic. A total of twenty−four Actinobacteria strains were isolated using four different isolation media (Starch casein agar, R2 agar, Actinomycete isolation agar, Streptomyces agar) and characterized basing on 16S rRNA gene sequences. Tests for secondary metabolites were performed using well diffusion method to detect antimicrobial activities against eight different pathogens, namely Staphyloccocus aureus ATCC 33591, Bacillus megaterium , Enterobacter cloacae , Klebsiella oxytoca , S. enterica serotype Enteritidis, S. enterica serotype Paratyphi ATCC 9150, S. enterica serotype Typhimurium ATCC 14028 and Vibrio cholerae . Antimicrobial properties were detected against Salmonella paratyphi A and Salmonella typhimurium at the concentration of 0.3092±0.08 g/ml. The bioactive strains were identified as Gordonia terrae , Leifsonia soli and Terrabacter lapilli. Results from this study showed that the soil of Deception Island is likely a good source of isolation for Actinobacteria. The volcanic soil Actinobacteria are potentially rich source for discovery of antimicrobial compounds.
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Abstract

Previous onomastic research into proper names in the Internet has typically been based on traditional and classic onomastic methodology. As a result, researchers have focused on the classification of names, the analysis of their structure, etymology, or function. In this paper, this traditional approach is compared with the new possibilities afforded by medioonomastics, a fast growing method which is combining the onomastic tradition and mediolinguistics. This paper provides only an outline and is only preliminary, although some analysis is also presented. It reviews onomastic techniques and the medioonomastic analysis of the names that function within the various types of texts in the Internet. Some examples are taken from Internet memes, as well as from Facebook profiles. One of these names is the Polish given name, Janusz, which is a brilliant example of the specific new functions, connotations and general semantic values generated by the Internet. This name has gained a new meaning: ‘a typical Polish man’, ‘unfashionable man’, ‘a redneck’. Another name is the title of the Facebook profile Chujowa Pani Domu, based on the TV-series Perfekcyjna Pani Domu, as a kind of semantic and pragmatic re-construction of the latter name. In the conclusion, the necessity of considering not only the type of object-named, but also the medium and especially the Internet, is emphasized. Such studies may offer a correct procedure for analysis which include the new medioonomastic methodology.
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Abstract

The article analyses the results of mass survey conducted in the framework of the project of the Volkswagen Foundation “Bi- and multilingualism between intensification of conflict and conflict resolution. Ethno-linguistic conflicts, language politics and contact situations in post-Soviet Ukraine and Russia”. Research’s aim was to understand to what extent the state language policy in the area of mass media and cultural sphere meet the expectations of the citizens of Ukraine. It underlines regionally marked attitude towards the strategy of language policy: the Western part of the country prefers Ukrainian language, South – Russian, and Center and North take intermediate positions.
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Abstract

Photodegradation by sunlight radiation is one of the most destructive pathways for pesticides after their application in the field. The generated photoproducts can exhibit various toxicological properties and affect non–target organisms. Sulcotrione is a herbicide believed to be a relatively non–toxic alternative to atrazine herbicides used on corn fields. Despite many tests required for placing plant protection products on the market, it still happens that transformation pathway and the toxicological profile of these compounds is not fully understood. The results presented in this article are complementary to the research performed by a research group from National Center for Scientific Research (CNRS) at the University of Blaise Pascal (Auvergne, France). Sulcotrione is one of main herbicides used to protect the maize plantations in the region of Auvergne (France), as well as in Poland. As part of the experiments, the distribution of sulcotrione under the influence of polychromatic radiation (fluorescent lamp, l > 295 nm, suitable for environmental tests) in aqueous solution of pH 6.5 was tested. The main products of these reactions were 1H–xanthene–1,9–dione–3,4–dihydro–6–methylsulfonyl (CP) and 2-chloro-4-methylsulfonyl-benzoic acid (CMBA), which are the result of intra-molecular cyclization and hydrolysis of sulcotrione, respectively. These products were quantified by using HPLC-diode array detector analysis. The studies clearly show an increase in toxicity towards tested organism (Vibrio fischeri bacteria) with the increase of irradiation time and appearance of the photoproducts. The results suggest that the observed increase in toxicity may be rather attributed to the occurrence of the same minor photoproducts than to the presence of the major photoproducts (CP and CMBA). Identification of the minor photoproducts could not be performed using the current instrumental equipment.
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Abstract

Post-truth and parody in old and new media – This paper presents a description of a few issues of the satirical magazine Il Male, published in Italy in the second half of the 1970s. These special issues – somewhat parodies – copied the typographic format of the main Italian newspapers of that period and were filled with odd and invented news. In some respects these publications anticipate parody and falsification in the digital era. In particular, some Internet sites that play on the slight distinction between false and true reports, and make us reflect upon the reliability of the information, can be considered as heirs to this experiment.
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