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Number of results: 13
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Abstract

Transplants can save lives, but only if the donor tissue is compatible with the recipient's body. Understanding how the body identifies and rejects foreign tissue is crucial for success. The molecules responsible for this are known as major histocompatibility complex (MHC) proteins.
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Authors and Affiliations

Jacek Nowak
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Abstract

Przeszczep może uratować życie, ale tylko wtedy, gdy tkanka dawcy jest .zgodna" z organizmem biorcy. Co to znaczy i dlaczego organizm potrafi zidentyfikować i odrzucić obcą tkankę? Odpowiadają za to białka głównego kompleksu zgodności tkankowej - MHC.
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Authors and Affiliations

Jacek Nowak
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Abstract

This article presents the results of research on carbonate rock samples taken from Triassic sediments of the northern area of Chorzów City. The aim of the research was to identify the mineral phases of these rocks, especially carbonate phases. The rocks from the roof part of the Bundsandstein profile and floor part of the Muschelkalk profile - Gogolin Beds - are typical sediments from the northern part of Chorzów City. These rocks were mined in the XIX century and the beginning of the XX century. The article also presents the results of research on samples of carbonate rocks taken from investigated strata. It provides a Petrographic description, the results of microscopic analysis executed in polarized, transmitted light, X-ray analysis, and microprobe measurements using a scanning microscope. The results of these analyses showed that dolomites dominate in the Bunsandstein strata. Dolomites (The sampled rocks?) are composed mainly of dolomite, but sparry calcite was also identified. Moreover, quartz, clay minerals, muscovite and iron minerals were observed in the Bundsandstein rocks. The Muschelkalk sedimentsare mainly represented by limestone. In some areas, conglomerates were also found. The conglomerates are composed of carbonate rock boulders connected by carbonate cement. Two generations of calcite were observed while investigating the limestone. The first generation calcite is micritic, and the second generation calcite forms sparry crystals different in size and shape. In some areas of the sparry calcite it is possible to observe perfect rhobohedral cleavage. Moreover, dolomite, rhodohrosite, and noncarbonate minerals like quartz, muscovite, and clay minerals were identified. The results of microscopic analysis also showed that the limestone is different in texture. The limestone presents the following textures: biomorphic, detrical, sparry, microsparry and micritic.

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Authors and Affiliations

Katarzyna Stanienda
Jacek Nowak
Tomasz Kukiełka
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Abstract

The Neogene basaltoid intrusions found in the S-7 borehole in the Sumina area (USCB) caused transformations of the adjacent Carboniferous rocks. The mineral and chemical compositions of the basaltoides are similar to those of the Lower Silesian basaltoides. The transformations that took place in the vicinity of the intrusion were manifested in the formation of natural coke, the secondary mineralization of these rocks (calcite, chlorite, zeolites and barite) and in the specific distribution of rare earths (REY). Among REY, the light elements (LREY) had the highest share, while the heavy elements (HREY) had the lowest share. Regardless of the lithological type of the analyzed rock, with increasing distance from the intrusion, the percentage of MREY and HREY elements increases at the expense of the light elements LREY. All analyzed distribution patterns of the REYs are characterized by the occurrence of anomalies, which often show a significant correlation with the distance of sampling points from the basaltoid intrusion. The specific distribution of REYs in the vicinity of the intrusion of igneous rocks is an indication of the impact of hydrothermal solutions associated with the presence of basaltoides on the rocks closest to them located at a temperature of over 200°C.

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Authors and Affiliations

Zdzisław Adamczyk
ORCID: ORCID
Joanna Komorek
Jacek Nowak
Małgorzata Lewandowska
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Abstract

This article presents the results of the study of changes in mineral and chemical composition of artificial aggregates consisting of coal shale (a hard coal mining waste) and fluidized ashes. Such an aggregate was used for road construction. After completion of the construction works but before making the road available for public use, significant deformation of the surface in the form of irregular buckling of the asphalt layer occurred. It was excluded that this resulted from mining damage, design errors or performance mistakes, among others. A study of the materials that had been incorporated in the construction layers was undertaken in order to find the component and the mechanism responsible for the buckling of the road surface. A comparison of the mineral and chemical composition of aggregate samples collected from the embankment where the road buckled with the reference sample and samples from places without deformations showed that the bumps in the road embankment consisted of minerals that were not initially present in the aggregate. Wastes produced as a result of high temperatures (slag and power plants ashes, metallurgical wastes) are not as stable in terms of chemical and phase composition in the hypergenic environment. As a result of the processes occurring in the road embankment, anhydrite, which is the primary component of fluidized ashes, was transformed into gypsum and ettringite. As a result of contact with water CaO (present in fluidized ashes) easily changed into calcium hydroxide. As the crystallization of these minerals is expansive, it resulted in the filling of pores and, in extreme cases, in a substantial increase in the volume of the aggregate and, consequently, in the deformation of the road surface.
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Authors and Affiliations

Zdzisław Adamczyk
Marcin Grygierek
Marian Łupieżowiec
Jacek Nowak
Ewa Strzałkowska
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Abstract

Rare earth elements are characterized by the high risk of their shortage resulting from limited resources. From this reason REE constitute a group of elements of special importance for the European Union. The aim of this study was to evaluate ashes from the burning of coal in fluidized bed boilers as an potential source of REY . Twelve samples of fly ash and bottom ash taken from power plants in Poland were analyzed. Tests have shown that despite some differences in chemical composition, the fly ash and bottom ash from fluidized beds could be classified as the calsialic, low acid type. It was found that fly ashes contained more REY than bottom ashes. Among REY , the light elements (LREY ) had the highest share in the total REY content in both fly ashes and bottom ashes. Heavy elements (HREY ) had the lowest content. The normalized curves plotted for fly ash samples within almost all of their entire range were positioned above the reference level and these curves were of the L-M or H-M type. The content of the individual REY in these samples was even twice as high as in UCC . The normalized curves plotted for bottom ash samples were classified as of L, L-M or H type. They were positioned on the reference level or above it. The content of the individual REY in these samples was the same or up to about 4 times lower than in UCC. It was found that the content of critical elements and of excessive elements in fly ash and bottom ash differs, which has an effect on the value of the outlook coefficient Coutl, and which is always higher in the case of fly ash than in the case of bottom ash. Nevertheless, the computed values of the outlook coefficient Coutl allow both fly ash and bottom ash from fluidized beds to be regarded as promising REY raw materials.
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Authors and Affiliations

Zdzisław Adamczyk
Joanna Komorek
Małgorzata Lewandowska
Jacek Nowak
Barbara Białecka
Joanna Całusz-Moszko
Agnieszka Klupa
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Abstract

The S-7 borehole log from the Sumina area (USCB Poland) revealed the presence of three basaltic veins

originating from a basalt dyke. Coal interlayers in the rocks surrounding the basaltic veins have been coked to

form natural coke. Photometric measurements revealed that the optical properties of the studied natural coke

samples are characteristic of semi-graphite (Rmax > 9%). The natural coke matrix of all of the analyzed samples

has a biaxial negative optical character. Vitrinite in the examined natural coke samples is characterized by a

lower optical anisotropy than that of the natural matrix and it has a biaxial positive optical character. Vitrinite

in almost all samples taken at locations more distant from the intrusion has a biaxial positive optical character.

A reversal of the changes of the true maximum vitrinite reflectance and bireflectance with changing distance

from the second basaltic vein has been observed. The temperature regime that acted upon the dispersed organic

matter located in the immediate vicinity of the intrusion, estimated on the basis of the selected experimental

data, is suggested to be higher than 750 °C.

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Authors and Affiliations

Zdzisław Adamczyk
Magdalena Kokowska-Pawłowska
Joanna Komorek
Agnieszka Klupa
Małgorzata Lewandowska
Jacek Nowak

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