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Abstrakt

A gigantic amounts of data and information on molecules that constitute the very complex cell machinery have been collected, classified and stored in data banks. Although we posses enormous amount of knowledge about the properties and functions of thousands of molecular entities, we are still far from understanding how they do work in a living cell. It is clear now that these molecules (genes, proteins) are not autonomous, that there is no direct linear relation between genotype and phenotype, and that the majority of functions are carried and executed by concerted molecular activity, and that the majority of diseases are multifactorial. A basic property of the matter in a living cell (both normal and pathologic) is an interaction between variety of macromolecules, mainly proteins, genes (DNA) etc. In a process of self-organization they are able to form an active molecular biologic system – a complex, labile and dynamic network which integrity is secured by non-covalent bounds. In this essay some basic properties of network structure and the universal rules that govern them are described. Network or system biology is promising new research approach in biology and medicine.
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Four Geodynamical Expeditions of the Polish Academy of Sciences carried through wide research seismic program in West Antarctica in 1979-1991. Three of these expeditions operated in the Bransfield Strait. The experiment of deep refraction and wide-angle reflection in West Antarctica focused on deep structure of the lithosphere, mainly of the Earth's crust. The network of deep seismic soundings (DSS) profiles covered all the Bransfield Strait. Five land stations on the South Shetland Islands, three stations on the Antarctic Peninsula and nine ocean bottom seismographs (OBS) recorded seismic waves, generated by explosions in a sea. The Bransfield Rift and the Bransfield Platform form a marginal basin against a volcanic arc of the South Shetland Islands. The paper presents new results of 2-D seismic modeling for network of five selected profiles. Four of them, ranging in lenght from 150 to 190 km, crossed main structures of the Bransfield Strait and the fifth, which connected the other ones and was 310 km long, ran along the Bransfield Rift. Two or three seismic models were presented for each profile. Finally, mutually corrected and controlled 2-D models of described profiles were constructed. They all presented spatial complex structure of the Earth's crust in a young rift of the Bransfield Strait, including extent of its main element i.e. anomalous high velocity body (HVB) (Vp > 7.4 km/s), detected in 10-30 km depth range except profile DSS-4 (southwest part of the Bransfield Strait). This inhomogeneity is interpreted as intrusion of the upper mantle (?asthenosphere) during stretching of the continental crust. The Moho discontinuity was found at depth 30-35 km, with velocities equal to about 8.1 km/s.
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The paper deals with the structural variability and generative reproduction of Saxifraga oppositifolia populations in eight localities situated in Western Spitsbergen. The localities differed in terms of humidity, soil fertility, microclimate and frequency of disturbances. The population structure, the growth and development rate of individuals in the sea terrace and at the peat-bog prove that a dense plant cover influences positively the development of S. oppositifolia. The size of individuals, their biomass and population density is limited in most of the studied localities. Solifluction is the factor influencing the development of a population to the greatest extent. Of all the researched populations the weakest development was observed in the active structural grounds. Yearly changes in the structure of the populations as well as the yearly growth of the species studied are limited. The longevity, the development rate and size of the seedling recruitment are subject to modifications caused by the solifluction.
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Material for this paper was collected during the BIOMASS-SIBEX research programme, and consisted of 97 samples taken at 47 stations in Drake Passage and Bransfield Strait (Antarctica). The samples were taken by hauling Nansen nets vertically through the 0-100, 100 - 300 and 300 - 500 m layers at the end of December 1983 and the beginning of January 1984. Four Chaetognatha species were recorded in the study region: Eukrohnia hamata, Sagitta gazellae, Sagitta mari and Sagitta planctonis. The population structures of the dominant species E. hamata and also S. gazellae were analyzed in the context of the region's hydrology. Certain regularities are apparent in the distribution of the developmental stages of E. hamata in water column. Mature specimens of this species inhabit deeper waters than juveniles. The highest proportions of juveniles in the entire population of E. hamata were recorded in slightly warmer waters.
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In this paper, the authors present a robot for pipe inspection and exploration, which has in its structure a module for the maintenance of a constant pressure force between the robot's wheels and the inside diameter of the pipe. The paper starts with a short introduction about necessity of the presented solution followed by design aspects and finalizing with the test of the developed compliant module.
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Abstrakt

Ilość aktualnie działających szpitali w Polsce szacuje się na ponad 750 (publicznych i prywatnych). Mimo, że projektowanie, realizacja i wyposażenie szpitali jest określone szeregiem aktów prawnych, permanentne problemy finan-sowe publicznej służby zdrowia i niedoinwestowanie powoduje, że nasze szpitale odbiegają od stanu pożądanego i standardu reprezentowanego przez jednostki w krajach wysoko rozwiniętych. Wieloletnia praktyka w projektowaniu i realizacji pozwala na sformułowanie szeregu uwag o najczęściej występujących nieprawidłowościach, wpływających na zwiększenie ryzyka występowania błędów medycznych i zdarzeń niepożądanych.
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The aim of the article is to bring closer a part of the world’s image that is characteristic for the rural community and the richness and variety of the folk culture inscribed in the proprial structures. As a result, this subject requires an integration of different research methods elaborated within the fields of onomastics and dialectology, including linguistic methods of researching a lingual image of the world. The onymic material is as follows: appellative surnames, originating from nicknames formed from dialectal lexemes, surnames motivated by nominal, dialectal hypocorisms, and finally, surnames formed from matronymic phrases (female names), which are an example of an aberrance of the patriarchal family model. Phonetic and formative phenomena should also be focused upon. These are crucial for certain social micro-communities, and are inscribed in the dialectal inflexions of anthroponyms (which function as separate surnames) and marginally in the female surnames with dialectal formants. Onyms with dialectal motivation refer to, and indirectly point, to the contemporary user, the past realities of living in the village community and the lingual and cultural background.
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Rozwój zarówno miasta jak i gminy Zielona Góra wykazuje postępujący proces niekontrolowanej linearnej rozbudowy tzw. urban sprawl. Zjawisko to, mimo że jest w historii miasta obecne od dawna, wraz z intensywnym rozwojem w XXI wieku, nasila się i wywiera niekorzystny wpływ na jakość zamieszkania, komunikację i dostępność. Przyjęte kierunki zmian zagospodarowania przestrzennego w aktualnych dokumentach strategicznych obszaru nowego miasta (od 1 stycznia 2015) powstałego z połączenia miasta i gminy wiejskiej Zielona Góra nie gwarantują zahamowania niekorzystnych procesów. Skutkiem występowania procesu niekontrolowanej linearnej rozbudowy jest nadmierny i zagęszczony rozrost struktur urbanistycznych wzdłuż dróg i szlaków komunikacyjnych. Uniemożliwia on optymalne wykorzystanie terenów położonych głębiej lub w drugiej linii od istniejącej infrastruktury oraz powoduje powstawanie martwych przestrzeni bez obsługi i dostępu komunikacyjnego. Wraz z każdą nową inwestycją (działka, zgodnie z przepisami, z zapewnionym dostępem do drogi publicznej), dostęp do rozproszonych terenów rekreacyjnych (zieleni), oddala się coraz bardziej od ścisłego centrum miasta. Pogarszające się warunki zamieszkania są bezpośrednią konsekwencją niekorzystnego zjawiska sprawl.
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Rock excavation is a basic technological operation during tunnelling and drilling roadways in underground mines. Tunnels and roadways in underground mines are driven into a rock mass, which in the particular case of sedimentary rocks, often have a layered structure and complicated tectonics. For this reason, rock strata often have highly differentiated mechanical properties, diverse deposition patterns and varied thicknesses in the cross sections of such headings. In the field of roadheader technology applied to drilling headings, the structure of a rock mass is highly relevant when selecting the appropriate cutting method for the heading face. Decidedly differentiated values of the parameters which describe the mechanical properties of a particular rock layer deposited in the cross section of the drilled tunnel heading will influence the value and character of the load on the cutting system, generated by the cutting process, power demand, efficiency and energy consumption of the cutting process. The article presents a mathematical modelling process for cutting a layered structure rock mass with the transverse head of a boom-type roadheader. The assumption was made that the rock mass being cut consists of a certain number of rock layers with predefined mechanical properties, a specific thickness and deposition pattern. The mathematical model created was executed through a computer programme. It was used for analysing the impact deposition patterns of rock layers with varied mechanical properties, have on the amount of cutting power consumed and load placed on a roadheader cutting system. The article presents an example of the results attained from computer simulations. They indicate that variations in the properties of the rock cut – as cutting heads are moving along the surface of the heading face – may have, apart from multiple other factors, a significant impact on the value of the power consumed by the cutting process.
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The Trinity Peninsula Group (Permo-Triassic?) at Hope Bay, northern Antarctic Peninsula, is represented by the Hope Bay Formation, more than 1200 m thick. It is subdivided into three members: the Hut Cove Member (HBF,), more than 500 m thick (base unknown), is a generally unfossiliferous marine turbidite unit formed under anaerobic to dysaerobic conditions, with trace fossils only in its upper part; the Seal Point Member (HBF2), 170—200 m thick, is a marine turbidite unit formed under dysaerobic conditions, with trace fossils and allochthonous plant detritus; the Scar Hills Member (HBF3), more than 550 m thick (top unknown), is a predominantly sandstone unit rich in plant detritus, probably formed under deltaic conditions. The supply of clastic material was from northeastern sources. The Hope Bay Formation was folded prior to Middle Jurassic terrestrial plant-bearing beds (Mount Flora Formation), from which it is separated by angular unconformity. Acidic porphyritic dykes and sills cut through the Hope Bay Formation. They were probably feeders for terrestrial volcanics of the Kenney Glacier Formation (Lower Cretaceous) which unconformably covers the Mount Flora Formation. Andean-type diorite and gabbro plutons and dykes (Cretaceous) intrude the Hope Bay Formation, causing thermal alteration of its deposits in a zone up to several hundred metres thick. All the above units are displaced by two system of faults, an older longitudinal, and a younger transversal, of late Cretaceous or Tertiary age.
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The present paper discusses the new Polish law on higher education in the context of the contrasted global and academic paradigms of university funding, governance, and organization. Its point of departure is the advent of international comparative data in higher education, the measurability of individuals, academic units and institutions in terms of research output, and the emergence of a new social contract between the state and universities. The key concepts used to evaluate the new law are competition in science, academic income structure and academic knowledge production structure, internationalists and locals in science, and vertical differentiation in national higher education systems. The new law is assessed in the context of the original reform proposal suggested by the national team of experts led by the present author and its long-term strategic choices are discussed in more detail, including a changing system of institutional evaluation, a revised system of academic degrees, and new excellence-focused national funding schemes.
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The paper presents a new numerical model of solidification processes in hypoeutectic alloys. The model combines stochastic elements, such as e.g. random nucleation sites and orientation of dendritic grains, as well as deterministic methods e.g. to compute velocity of dendritic tips and eutectic grains. The model can be used to determine the temperature and the size of structure constituents (of both, the primary solid phase and eutectics) and the arrangement of individual dendritic and eutectic grains in the consecutive stages of solidification. Two eutectic transformation modes, typical to modified and unmodified hypoeutectic alloys, have been included in the model. To achieve this, cellular automata and Voronoi diagrams have been utilized.
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The paper presents adaptation problem of lamellar/rod growth of eutectic. The transformation of eutectic microstructure was investigated systematically. A interpretation of the eutectic growth with theory minimum entropy production was presented.
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In Part I of this article, two-stage solidification model was presented. In this part we use our model to simulate solidification of the Al 7% Si alloy for two cooling rates and . Simulations have been performed for two eutectic transformation modes, typical for modified and unmodified alloys. Obtained cooling curves are qualitatively consistent with the typical cooling curves for modified and unmodified alloys. Moreover, evolution of cooling-curve characteristics is compared with the analytical model and found to be in close agreement.
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In this study, modification of the AZ91 magnesium alloy surface layer with a CO2 continuous wave operation laser has been taken on. The extent and character of structural changes generated in the surface layer of the material was being assessed on the basis of both macro- and microscopy investigations, and the EDX analysis. Considerable changes in the structure of the AZ91 alloy surface layer and the morphology of phases have been found. The remelting processing was accompanied by a strong refinement of the structure and a more uniform distribution of individual phases. The conducted investigations showed that the remelting zone dimensions are a result of the process parameters, and that they can be controlled by an appropriate combination of basic remelting parameters, i.e. the laser power, the distance from the sample surface, and the scanning rate. The investigations and the obtained results revealed the possibility of an effective modification of the AZ91 magnesium alloy surface layer in the process of remelting carried out with a CO2 laser beam.
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One of the more important elements of spatial information infrastructure is the organisational structure defining the obligations and dependencies between stakeholders that are responsible for the infrastructure. Many SDI practitioners and theoreticians emphasise that its influence on the success or failure of activities undertaken is significantly greater than that of technical aspects. Being aware of the role of the organisational structure in the creating, operating and maintenance of spatial information infrastructure (SII), Polish legislators placed appropriate regulations in the Spatial Information Infrastructure Act, being the transposition of the INSPIRE Directive into Polish Law. The principal spatial information infrastructure stakeholders are discussed in the article and also the scope of cooperation between them. The tasks and relationships between stakeholders are illustrated in UML, in both the use case and the class diagram. Mentioned also are the main problems and obstructions resulting from imprecise legal regulations.
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The academic environment of Wrocław emerged and developed in particularly difficult conditions of the post WWII era. Thanks to continuation of the tradition, experience and contributions of leading scientists from the former Jan Kazimier University of Lwów, it quickly achieved an important, internationally recognized position in particular in mathematics and chemistry. Two different sociological concepts of relations within the scientific community have developed simultaneously: (1) partnership between leaders and research team members, (2) hierarchical structure based on authority of a leader. History proved that both may be effective. Wrocław became a modern center of research management comparable to leading western universities. The general approach based on relationship „between master and a follower” has been replaced by the more effective relatioship „between a school and a follower”. Similarly to the Lwów tradition the Wrocław Scientific Society has played an integrative role in relations among scientists of different disciplines.
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Abstrakt

The presented work discusses the influence of material of foundry mould on the effect of modification of AlSi11 alloy. For this purpose castings were produced in moulds made of four various materials. Castings of the first type were cast in a metal die, the second ones in the conventional mould of bentonite-bound sand, those of the third type in the sand mould with oil binder, the last ones in a shell mould where phenol-formaldehyde resin was applied as a binder. All the castings were made of AlSi11 alloy modified with strontium. For a purpose of comparison also castings made of the non-modified alloy were produced. The castings were examined with regard to their microstructures. The performed investigations point out that the addition of strontium master alloy results in refining of the alloy structure, particularly of the α-phase, causes some morphological changes in the alloy and the refinement of eutectics. The advantageous influence of modifier on the structure of the examined silumin was observed particularly in the case of alloy cast either in the conventional oil-bound sand mould or in the shell mould. The non-modified alloy cast into a metal die exhibits a structure similar to those of modified alloy solidifying in the other moulds. The improvement in both tensile strength and unit elongation suggests that the modification was carried out correctly. The best mechanical properties were found for the alloy cast in a metal die, both with and without modification treatment.
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In paper is presented results of studies concerning ingot of Al with a purity of 99.5% cast with use of stand of horizontal continuous casting. Mainly together with casting velocity was considered influence of electromagnetic stirrer, which was placed in continuous casting mould on refinement of ingots structure and theirs usability to plastic deformation. Effect of structure refinement and usability to plastic deformation obtained by influence of electromagnetic stirring was compared with refinement obtained by use of traditional inoculation, which consists in introducing of additives i.e. Ti and B to metal bath. On the basis of obtained results was affirmed that inoculation realized by electromagnetic stirring in range of continuous casting mould guarantees improvement in structure refinement and usability to rolling of pure Al continuous ingots.
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Metallic foams are materials of which the research is still on-going, with the broad applicability in many different areas (e.g. automotive industry, building industry, medicine, etc.). These metallic materials have specific properties, such as large rigidity at low density, high thermal conductivity, capability to absorb energy, etc. The work is focused on the preparation of these materials using conventional casting technology (infiltration method), which ensures rapid and economically feasible method for production of shaped components. In the experimental part we studied conditions of casting of metallic foams with open pores and irregular cell structure made of ferrous and nonferrous alloys by use of various types of filler material (precursors).
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The objective of the paper is to use the model of Complexity Scales and Licensing (Cyran 2003, 2010) to account for the existence of two prosodic types: ‘syllable’ and ‘word’ languages (Auer 1993, Szczepaniak 2007), which roughly correspond to syllable-timed and stress-timed languages. We will postulate that these categories are not primitive and that many of their phonological characteristics can be derived from simpler mechanisms of licensing. It will be also argued that the phenomenon of contrast plays an important role in prosodic typology and may infl uence syllable structure. Languages use more marked syllabic confi gurations in order to optimise contrast expression. We will carry out an analysis on a simple hypothetical language in order to demonstrate the interdependence of syllabic complexity and the contrastive potential of a syllabic unit.
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The method of pressure die casting of composites with AlSi11 alloy matrix reinforced with 10 vol. % of SiC particles and the analysis of the distribution of particles within the matrix is presented. The composite castings were produced at various values of the piston velocity in the second stage of injection, at diverse intensification pressure values, and various injection gate width values. The distribution of particles over the entire cross-section of the tensile specimen is shown. The index of distribution was determined on the basis of particle count in elementary measuring fields. The regression equation describing the change of the considered index was found as a function of the pressure die casting parameters. The conclusion presents an analysis of the obtained results and their interpretation.
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The aim of this paper was to determine the effect of heat treatment for the corrosion resistance of the ZnAl40Ti2Cu alloy under “acid rain” conditions. ZnAl40TiCu alloy after supersaturation and after supersaturation and aging was studied. Potentiodynamic studies, potentiostatic studies and studies on structure of the alloy top layer of samples after corrosion tests were carried out. These investigations indicated a significant influence of heat treatment on corrosion resistance of the ZnAl40Ti2Cu alloy. The highest increase in corrosion resistance comparing to the alloy in the as-cast condition may be obtained by supersaturation. A significant influence of the aging temperature and time on corrosion resistance was proved.
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The population structure, seasonal and diel changes in vertical distribution of two siphonophore species, Dimophyes arctica and Pyrostephos vanhoeffeni , in Croker Passage (Antarctic Peninsula) are examined, and compared with the results obtained by other au− thors in various oceanic areas. Zooplankton samples were taken at discrete depth intervals between 0 and 1200 m during day and night shifts, in both summer and winter seasons. Dimophyes arctica was present both in polygastric and eudoxid forms, with the latter being dominant throughout the entire study period. The results obtained demonstrate that Antarctic waters clearly enhance the reproductive ability of this species when compared with specimens from other oceanic regions. Maximum densities of Dimophyes arctica were recorded in December in the 200–400 m depth horizon. However, high concentrations of eudoxids were also recorded at deeper parts of the water column. Pyrostephos vanhoeffeni was, in contrast, most abundant in autumn and winter, and both species were found to proliferate and disperse or sink further down the water column during autumn and winter. Daily vertical migration was observed only during the summer period.
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