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Number of results: 21
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Keywords krill migration

Abstract

At the ice edge krill undergoes diurnal migrations with the period of 12 hours and amplitude of about 6 meters. The mean depth of krill occurrence is 41 m, shallower then for open waters. In our opinion these migration parameters are characteristic of juvenile adolescent krill dominating at the ice edge.
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Abstract

Contemporary world brings along a continuing interpenetration of cultures strengthened by the migration revolution. The social space created by multiplicity of ethnic groups is very often a result of migration processes which totally formed such states as Canada or Australia. The sources of the European multiculturalism were, on the one hand, the officially accepted workforce, on the other hand – immigration being the effect of the colonial past of such states as France, Great Britain or Germany
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Abstract

On the basis of hydroacoustic observations it is shown that migrations of krill during spring are stronger than during summer. Migrations of krill are described by the function: H(t) = A + Bcos((2ᴨt/T + φ ) + C c o s ( 2 ᴨt/T + φ ), where: H is depth of the mass center of krill biomass, A — mean depth of krill occurrence, В — amplitude of migrations with period T! = 24 h, С — amplitude of migrations with period T2 = 12 h, (φ1, φ2 — phases of migration process with T, = 24 and T2 = 12 hours. Parameters of the equation are the following: spring — A = 62.2 m, В = 19.5 m, С = 4.6 m, φ1 = 0.1 h, φ2 = 0 . 1 5 h; summer — A = 75.8 m, В = 0.5 m, С = 3.6 m, φ1 = 1.8 h, φ2 = 6.4 h.
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Abstract

The article presents the author’s considerations relating to the current and common problem of multiculturalism. Nowadays “multiculturalism” can be defined as co-existence – in the determined physical, social and political sphere as well as in a concrete historical period of time – of many ethnic groups representing different axiological and normative systems. The social created by multiplicity of ethnic groups is very often a result of migration processes which totally formed such states as Canada or Australia. The sources of the European multiculturalism were, on the one hand, the officially accepted workforce as Federal Republic of Germany, on the other one – immigration being the effect of the colonial past of such states as France, Holland or Britain. All these countries took up more or less advanced actions towards being able to deal with the deepening ethnic diversification. There appeared political project – multiculturalism.
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Abstract

The traditional model of the multinational city, which was based on the harmonious coexistence of separated ethnic residential districts and common multinational public areas, where the exchange of services and goods took place, gives way to the contemporary model, based on the principle of dispersion and segmentation. In the postmodern city virtual space has increasingly becoming a platform of exchange: numerous economic, social and cultural functions are performed through the ubiquitous electronic communications. Public space, symbolic for the European concept of the city, is losing many of its previous functions in favour of the Internet. The dispersion of immigrants in the structure of the multinational city is conducive to the emergence of an attractive, kaleidoscopic and multicultural urban organism, their separation in ghettos results in intensification of pathologies. Integration is assuming the form of a network, while separation that of walls.
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Abstract

This article reflects some trends and challenges in Germany in connection to immigration. The need of educational and scientific discussion and reflection of migration-specific themes are dictated by the contemporary reality requirements of almost all European countries. Change in society, associated primarily with the processes of immigration, affects the processes and systems of goal-countries, especially the education system.
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Abstract

This article explores caring through feeding as an important aspect of transnational family life, and analyzes the practices connected to sending food products home, supervising what the family eats, and changing consumption patterns. It focuses on Filipino migrants to the United States who maintain transnational ties with their families. With a history of colonial encounter, the United States has been a popular migration destination, and has also strongly influenced food consumption. The study shows the ways in which packages from abroad (balikbayan boxes) express love and care, and how they allow migrants to control food consumption of the family in the country of origin. By looking at the goods the immigrants put in the packages, and the way these are received, it is possible to uncover the dynamics of love, care, and intimacy in transnational families, which often translate into power, tensions, and control among family-members. The article analyses how food products sent in the packages work, bringing with them new ideas and practices, creating imaginaries of migration, and building the social prestige of the immigrant. Using the concept of “social remittances”, the article also shows the changing patterns of food consumption in the Philippines.
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Abstract

Observations indicate a constantly decreasing mean age of shoal. In consecutive years of investigations a loss of older individuals was recorded. At present the catches consist of 3—14 years old fishes; 9—10 years old dominate. During the austral summer the fish most probably do not migrate. The shoal of the shelf maintains approximately constant frequency and dominance in classes of length.
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Abstract

Considering the recent mass movement of people fleeing war and oppression, an analysis of changes in migration, in particular an analysis of the final destination refugees choose, seems to be of utmost importance. Many international organisations like UNHCR (the United Nations High Commissioner for Refugees) or EuroStat gather and provide information on the number of refugees and the routes they follow. What is also needed to study the state of affairs closely is a visual form presenting the rapidly changing situation. An analysis of the problem together with up-to-date statistical data presented in the visual form of a map is essential. This article describes methods of preparing such interactive maps displaying movement of refugees in European Union countries. Those maps would show changes taking place throughout recent years but also the dynamics of the development of the refugee crisis in Europe. The ArcGIS software was applied to make the map accessible on the Internet. Additionally, online sources and newspaper articles were used to present the movement of migrants. The interactive map makes it possible to watch spatial data with an opportunity to navigate within the map window. Because of that it is a clear and convenient tool to visualise such processes as refugee migration in Europe.
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Abstract

The induction of phytoremediation by addition of complex substrates, such as sewage sludge (e.g. from the food industry), allows for better conditions of plant growth, however, it also increases the risk of chemical compounds leaching to the soil solution. Biogenic compounds occurring in sludge such as nitrogen, organic carbon and phosphorus when migrating with soil solution down the soil profile can lead to underground water contamination. The paper assesses the effect of sewage sludge inducted phytoextraction of Zn, Cd and Pb with the use of Sinapis alba L. (White mustard), Medicago sativa L. (Alfalfa) and Trifolium resupinatum L. (Persian clover) as well as the migration of biogenic compounds (nitrogen, organic carbon and phosporus) in soil solution. Research was conducted in controlled conditions of a phytotronic chamber in which the lysimetric experiment was carried out in order to monitor the changes of total nitrogen, ammonia, phosphates, organic carbon and pH every 3 weeks during the 112 days of the entire experiment. Based on the obtained results it was found that there is no risk of underground water contamination by investigated substances present in sewage sludge, because there was no indication of increased ammonia and carbon migration to the deeper parts of the soil profile.The only exception was the migration of nitrogen compounds other than ammonia (possibly nitrates and nitrites). Due to sewage sludge application the highest concentrations of ammonium nitrogen (211 mgN-NH4 l -1), total nitrogen (299 mg N l-1) and organic carbon (200 mg TOC l-1) were noted at a layer of 30 cm (from top of the column/lysimeter) after 3 weeks of the conducted process. With time a decrease of ammonium nitrogen as well as organic carbon concentration in all columns was noted. There was no indication of phosphates in the soil solution during the entire experiment, which was due to the high cation exchange capacity of the soil matrix.
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Abstract

The most common chemical’s spills in typical transportation accidents are those with petroleum products such as diesel fuel, the consequence of which is an extensive pollution of the soil. In order to plan properly fuel recovery from the soil, it is important to gain information about the soil depth which may be affected by pollutant and to predict the pollutant concentration in different soil layers. This study deals with the impact of basic atmospheric conditions, i.e. air temperature and humidity on the diesel fuel migration through the soil. The diesel fuel was spilled into columns (L = 30 cm; D = 4.6 cm) filled with sandy and clay soil samples, and its concentrations at various depths were measured after 11 days under various air temperature (20 and 40°C) and relative humidity (30–100%) conditions. The effects observed were explained by understanding physical processes, such as fuel evaporation, diffusion and adsorption on soil grains. The increase in temperature results in higher fuel evaporation loss and its faster vertical migration. The relative humidity effect is less pronounced but more complex, and it depends much on the soil type.
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Abstract

The paper examines the most important Italian historical novel and focuses on its principal migration routes, especially concerning main characters. It also examines a variety of representations of border and frontier (also in a metaphorical sense) in the novel.
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Abstract

The general objective of this research has been to identify the factors and conditions of migration of CaCO3 within glaciers and their marginal zones in Svalbard . Special attention has been paid to the cryochemical processes responsible for precipitation of calcium carbonate in icing (naled ice) formed near fronts of polythermal glaciers during winter. Estimates of the importance of those processes in respect of the general mineral mass transfer in the glacier system are attempted here. Field studies concerning the carbonate contents in proglacial sediments and icing fields were carried out in the Werenskioldbreen and the Elisebreen basins (S and NW Spitsbergen respectively). A functional model of CaCO3 migration in a glacier system is proposed which indicates the various paths of the mineral mass flow. Considerations on intensity of glacial processes permitted quantitative estimation of the particular components in respect to the Werenskioldbreen basin. Cryochemical processes do not appear to be of overriding importance in such migration but, clearly, they play a specific role in retaining CaCO3 in the proglacial zone on land. The crystalline forms present in the icings, which have many lattice defects, are very easily re-dissolved or removed by wind.
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Abstract

Depopulation is understood as a real population loss in an area represented by a negative population change. In the present-day Poland, the process is particularly distinct in the economically underperforming areas situated on the peripheries of large urban centres, but some of the most populous cities are also affected by it. The purpose of the presented research using Webb’s typology was to identify Polish poviats that were depopulating in all the years from 2002 to 2014 as a result of natural population decline and negative migration balance (two-factor depopulation). In the research, special attention was given to the rate of change in the number of population (total and by age group) and to a net natural and migration loss in the selected poviats. Selected characteristics of the 2014 population age structure in Poland were also evaluated. The basis for all findings presented in the paper is vital and migratory statistics for the years 2002 to 2014 and the data on poviats’ population age structure from 2002 and 2014 published by the Central Statistical Office.
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Abstract

The paper presents investigation results of the migration of a chemical compound contained in fly ash deposited on a dry furnace waste landfill site exposed to weather conditions. Climate conditions are able to significantly affect chemical component distribution in a block of deposited, moving chemical compounds to different depths. The main aim of the investigations was to determine the chemical component distribution of deposited fly ash in the landfill. Identification of chemical components based on XRF analysis indicated the existence of differences in both tested storage layer and the fraction of fly ash.
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Abstract

Landfill leachate makes a potential source of ground water pollution. Municipal waste landfill substratum can be used for removal of pollutants from leachate. Model research was performed with use of a sand bed and artificially prepared leachates. Effectiveness of filtration in a bed of specific thickness was assessed based on the total solids content. Result of the model research indicated that the mass of pollutants contained in leachate filtered by a layer of porous soil (mf) depends on the mass of pollutants supplied (md). Determined regression functions indicate agreement with empirical values of variable m′f. The determined regression functions allow for qualitative and quantitative assessment of influence of the analysed independent variables (m′d, l, ω) on values of mass of pollutants flowing from the medium sand layer. Results of this research can be used to forecast the level of pollution of soil and underground waters lying in the zone of potential impact of municipal waste landfill.
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Abstract

The aim of this article is to analyze both the motivations of foreign scholars to come to work in Poland – specifically Kraków – and their ways of adapting to this significant Polish academic center. Most studies on highly skilled migrants (HSMs) concentrate on the flows between developing and highly developed countries. We concentrate on Central and Eastern Europe. This paper, based on in-depth interviews with 23 foreign scholars working full-time at four universities in Kraków, is a follow-up to a study presenting a 2015 analysis of websites of universities from Kraków. We look closely at barriers to and facilitators of foreign scholars’ adaptation to Poland and their perceived image of Poland and Polishness, their national identification and international contacts. We propose a typology comprised of “cosmopolitans”, “status seekers”, “enthusiasts”, and “commuters”. Our investigations reveal who decides to move to a semi-peripheral country such as Poland, and why. Certain parts of the narratives can be used in building a strategy of attracting more international scholars to academic centers such as Kraków.
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Abstract

The purpose of the piece The Strategikon as a source — Slavs and Avars in the eyes of Pseudo- Maurice, current state of research and future research perspectives is to demonstrate what the author of Strategikon knew about the Slavs and Avars and review the state of research on the chapter of the treatise that deals with these two barbarian ethnicities. As a side note to the description of contemporary studies of Strategikon, the piece also lists promising areas of research, which have not yet received proper attention from scholars.
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Abstract

Low-frequency noise measurements have long been recognized as a valuable tool in the examination of quality and reliability of metallic interconnections in the microelectronic industry. While characterized by very high sensitivity, low-frequency noise measurements can be extremely time-consuming, especially when tests have to be carried out over an extended temperature range and with high temperature resolution as it is required by some advanced characterization approaches recently proposed in the literature. In order to address this issue we designed a dedicated system for the characterization of the low-frequency noise produced by a metallic line vs temperature. The system combines high flexibility and automation with excellent background noise levels. Test temperatures range from ambient temperature up to 300◦C. Measurements can be completely automated with temperature changing in pre-programmed steps. A ramp temperature mode is also possible that can be used, with proper caution, to virtually obtain a continuous plot of noise parameters vs temperature.
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Abstract

The paper presents an overview of theoretical aspects of ultrasound image reconstruction techniques based on the circular Radon transform inversion. Their potential application in ultrasonography in a similar way as it was successfully done in the x-ray computer tomography is demonstrated. The methods employing Radon transform were previously extensively explored in the synthetic aperture radars, geophysics, and medical imaging using x-ray computer tomography. In this paper the main attention is paid to the ultrasound imaging employing monostatic transmit-receive configuration. Specifically, a single transmit and receive omnidirectional source placed at the same spatial location is used for generation of a wide-band ultrasound pulse and detection of back-scattered waves. The paper presents derivation of the closed-form solution of the CRT inversion algorithms by two different approaches: the range-migration algorithm (RMA) and the deconvolution algorithm (DA). Experimentally determined data of ultrasound phantom obtained using a 32-element 5 MHz linear transducer array with 0.48 mm element pitch and 0.36 mm element width and 5 mm height, excited by a 2 sine cycles burst pulse are used for comparison of images reconstructed by the RMA, DA, and conventional synthetic aperture focusing technique (SAFT). It is demonstrated that both the RMA and SAFT allow better lateral resolution and visualization depth to be achieved as compared to the DA approach. Comparison of the results obtained by the RMA method and the SAFT indicates slight improvement of the lateral resolution for the SAFT of approximately 1.5 and 1.6% at the depth of 12 and 32 mm, respectively. Concurrently, however, the visualization depth increase for the RMA is shown in comparison with the SAFT. Specifically, the scattered echo amplitude increase by the factor of 1.36 and 1.12 at the depth of 22 and 32 mm is demonstrated. It is also shown that the RMA runs about 30% faster than the SAFT and about 12% faster than the DA method
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Abstract

In this article I will attempt to answer the question of why systemic solutions to (social) problems of Polish economic migrants fail to be instituted in Poland by means of social negotiations. Therefore, while emphasising the social dimension of Polish migration, I briefly present its specificity and point to some associated threats. Referring to the category labelled as social problem, I demonstrate the nature of obstacles which prevent a debate on Polish migration in the area of social negotiations from taking root on public ground in Poland. I also refer to the mechanisms of degradation of the public sphere as those which are preventing the development of systemic solutions to the problems of Polish migrant workers by means of social negotiations.
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