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Sustained activation of P2X7 induces MMP-2- evoked cleavage and functional purinoceptor inhibition

Journal of Molecular Cell Biology 2018年第3期10卷 229-242页

作者： Christopher N. J. Young Natalia Chira Justyna Róg Rasha Al-Khalidi Magalie Benard Ludovic Galas Philippe Chan David Vaudry krzysztof zablocki Dariusz C. Górecki School of Allied Health Sciences Faculty of Health and Life Sciences De Montfort University Leicester LE1 5RR UK Molecular Medicine Laboratory Institute of Biomedical and Biomolecular Sciences School of Pharmacy and Biomedical Sciences University of Portsmouth Portsmouth PO1 2DT UK Laboratory of Cellular Metabolism Department of Biochemistry Nencki Institute of Experimental Biology of the Polish Academy of Sciences Pasteur Str. 02- 093 Warsaw Poland PRIMACEN Cell Imaging Platform of Normandy Inserm IBiSA and PISSARO Proteomic Platform Institute for Research and Innovation in Biomedicine University of Rouen 76821 Mont-Saint-Aignan France

P2X7 purinoceptor promotes survival or cytotoxicity depending on extraceUular adenosine triphosphate （ATP） stimulus Intensity controlling its ion channel or P2X7-dependent large pore （LP） functions. Mechanisms governing this operational divergence and functional idiosyncrasy are ill-understood. We have discovered a feedback loop where sustained activation of P2X7 triggers release of active matrix metalloproteinase 2 （MMP-2）, which halts ion channel and LP responses via the MMP-2-dependent receptor cleavage. This mechanism operates in cells as diverse as macrophages, dystrophic myoblasts, P2X7-transfected HEK293, and human tumour cells. Given that serum-born MMP-2 activity also blocked receptor functions, P2X7 responses in vivo may decrease in organs with permeable capillaries. Therefore, this mechanism represents an Important fine-tuning of P2X7 functions, reliant on both cell-autonomous and extraneous factors. Indeed, it allowed evasion from the ATP-induced cvtotoxicity in macrophages and human cancer ceils with high P2X7 expression levels. Finally, we demonstrate that P2X7 ablation eliminated getatinase activity in inflamed dystrophic muscles in vivo. Thus, P2X7 antagonists could be used as an alternative to highly toxic MMP inhibitors in treatments of inflammatory diseases and cancers.

关键词： P2X7 MMP-2 DMD macrophage β-dystroglycan CD44 cancer

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Tourist management in national parks in the Czech-German borderland:Bohemian ’Switzerland’ and Saxon‘Switzerland’

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Journal of Mountain Science 2020年第12期17卷 2853-2879页

作者： krzysztof KOLODZIEJCZYK Department of Regional Geography and Tourism Institute of Geography and Regional DevelopmentFaculty of Earth Sciences and Environmental ManagementUniversity of WroclawWroclaw 50-137Poland

In the article tourist management in two national parks in the Czech-German borderland are being compared,namely Bohemian ’Switzerland’(also known as Czech ’Switzerland’) and Saxon’Switzerland’.Situated on either side of the state border,they feature the same type of geographical *** accessibility,transborder links and the hiking trail network are analyzed using methodology sourced from graph *** result of the analyses is a classification of tourist hubs and tourist centers,as well as an indication of the main directions of tourist *** German national park is decidedly more accessible but with a detrimental effect on the natural environment primarily due to its fragmentation by a dense network of tourist *** both parks trails enter the core zone(in theory a strict protection area) but this occurs on a larger scale on the German *** the Czech national park a greater number of positive examples of managing tourist movements can be ***,larger areas managed for dispersion,or from which tourists are generally excluded,are located there.

关键词： National parks Tourist management Tourist trails Bohemian’Switzerland’ Saxon’Switzerland’

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Changes in the network of tourist trails in the border zones of the Czech Republic after entering the Schengen area

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Journal of Mountain Science 2020年第4期17卷 949-972页

作者： krzysztof KOLODZIEJCZYK Department of Regional Geography and Tourism Institute of Geography and Regional DevelopmentUniversity of WroclawWroclaw 50-137Poland

Among the factors influencing tourist trail network development are political issues, including the presence of state borders, the possibility of crossing them and the accessibility of border zones. In the article, it was decided to look at changes in the offer of tourist trails(hiking and cycling) along the entire border of the Czech Republic after the extension of the Schengen area(within this area, crossing the border is possible anywhere, and not only at official border crossings). It should be emphasized here that the borders of the Czech Republic over most of their length run through mountainous areas and, apart from political factors, natural features should have a major impact on the development of tourist routes. In order to determine the coherence of the current network of trails on both sides of the Czech Republic state border, modern tourist maps have been analyzed, determining the number of places where it is possible to cross the state border with the help of a marked tourist trail. Based on that, two indicators were introduced to determine the degree of openness with all neighboring countries as regards the opportunity to cross on a tourist trail. Changes in the historical situation, a comparison of the accessibility of the border area before entering the Schengen area and 2019, were analyzed for two study areas using archival maps. Over a decade after the extension of the Schengen area, the number of places where tourist trails of neighboring countries approach the border has clearly increased. Crossing is more often made possible using hiking trails than cycling routes(trails of the first type cross the border every 7.91 km, while the latter every 13.3 km), but considering the speed of movement, it can be assessed that the openness for cyclists is higher than for hikers. Moreover, in many places there is still significant potential for further integration of tourist trail networks as trails created in one country often do not have a continuation on

关键词： Tourist trails Schengen area Border zone Mountains Czech Republic

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A review on single-pass grinding processes

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Journal of Central South University 2013年第6期20卷 1502-1509页

作者： krzysztof NADOLNY Department of Production Engineering Faculty of Mechanical EngineeringKoszalin University of Technology

The most important grinding processes were realized in a single pass of the grinding wheel,such as continuous path controlled grinding (CPCG/Peelgrinding/HSP),CPCG with reduced contact of the grinding wheel (Quickpoint),single-pass longitudinal internal grinding,creep feed grinding (CFG),longitudinal cylindrical grinding with grinding wheels made of conventional abrasive materials and longitudinal internal cylindrical grinding using grinding wheels with zone-diversified structure.

关键词： single-pass grinding grinding efficiency, grinding wheels, surface roughness

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Factors determining changes in the network of marked hiking trails in the Sudetes

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Journal of Mountain Science 2024年第4期21卷 1075-1099页

作者： krzysztof KOŁODZIEJCZYK Department of Regional Geography and Tourism Institute of Geography and Regional DevelopmentFaculty of Earth Sciences and Environmental ManagementUniversity of WroclawNo.1Uniwersytecki Square50-137 WroclawPoland

Hiking trails are a basic type of tourist infrastructure,which,on the one hand,make areas available for tourist traffic,and on the other hand,can contribute to the protection of the natural environment(if they are well designed and maintained).Owing to the variety of performed functions,their designation is determined by several factors:natural,technical,economic,*** of trails change *** aim of this article is to determine exactly what factors influence transformations within the hiking trail networks and what is their *** this end,three study areas in the Sudetes were analysed:one on the Polish side of the Sudetes-the Table(Stołowe)Mountains,and two on the Czech side-the rock town near the village of Sloup vČechách and the central part of Zlatohorská*** analysis of changes in the shape of the networks over time was carried out,as well as surveys of institutions that were responsible for or influenced these *** areas are characterised by a significant level of changes in the trail *** the factors influencing these changes,the tourist attractiveness of the area,the resilience of the environment,the intensity of tourism traffic,the environmental transformations associated with it,the history of tourism development and land ownership changes should be considered the most *** each stage of forming networks,the key factor should be tourists’needs,including the desire to escape the urbanised *** this reason,trails should avoid roads with artificial(hard)surfaces and heavy automobile traffic.

关键词： Hiking trails Trail networks Graphs Tourist traffic Sudetes

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Tourism management in national parks:Sumava and Bayerischer Wald(Bavarian Forest)in the Czech-German borderland

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Journal of Mountain Science 2021年第9期18卷 2213-2239页

Along the Czech-German border there are four national parks,two Czech and two German,arranged in cross-border‘pairs’.This article focuses on the southern‘pair’formed by the parks of?umava and Bayerischer Wald(Bavarian Forest).The aim is to evaluate and compare tourism organization in their areas,taking into account selected aspects of management:the network of hiking trails with its related infrastructure,transport accessibility,a typology of tourist centers,as well as directions and destinations of tourist *** on the results,it can be concluded that the availability of geographical space for tourists is much greater in the German than in the Czech national park,and the tourism infrastructure is clearly more extensive there,including the network of tourist *** is mainly due to the longer and fairly uninterrupted development of tourism in this area.?umava National Park can be identified as a model in terms of how to adjust the directions of tourist movements and the layout of the tourist trail network to the needs of natural *** the basis of observations in both national parks,it is possible to indicate various solutions that,after appropriate adaptation,may bring benefits to other protected areas.

关键词： National parks Tourism management Tourism infrastructure Tourist trails Sumava Bayerischer Wald(Bavarian Forest)

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Networks of hiking tourist trails in the Krkono?e(Czech Republic) and Peneda-Gerês(Portugal) national parks-comparative analysis

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Journal of Mountain Science 2019年第4期16卷 725-743页

作者： krzysztof KO?ODZIEJCZYK Department of Regional Geography and Tourism Institute of Geography and Regional Development University of Wroclaw

Tourist trails as a linear form of tourist infrastructure fulfill various functions(i.e. recreational, ecological, economic, social, ensuring safety). They are especially important in national parks, where in selected areas tourist penetration is allowed only along specially designed, official routes. A well-planned layout of tourist trails with appropriate facilities can help to limit the negative consequences of tourist pressure on protected natural areas. The aim of the article is a comparison of offers for active tourists in two mountain national parks(the Krkono?e National Park in the Czech Republic and the Peneda-Gerês National Park in Portugal), taking into consideration the marked hiking trails – the most frequently used type of tourist trails. As a result the level of area coverage by the networks of hiking trails was assessed, as well as their adequateness towards the needs of tourists. The descriptive analysis was based on author's personal observations. In the examination of hiking trails as part of a system, some elements of the graph theory were used, especially coefficients for topologic analysis of spatial structure. This method enables simplification of a network, comparison of various areas and making some assumptions concerning tourist infrastructure, which is a crucial factor while analyzing trails from a tourists' point of view. In both analyzed national parks the relief is quite similar, as well as their locations near national borders, what justifies the choice of the areas scrutinized in the paper. What differ them are patterns of tourism development and the current ways of undertaking active tourism. Not similarities but the two latter factors resulted in a distinct character of the two compared networks of trails and facilities connected with them. The system of hiking trails and tourist infrastructure seem better developed in the Krkono?e National Park, what can be explained by historical and social conditions, especially the adopted model

关键词： Hiking tourist trails Tourist infrastructure Mountains National parks Network Graph analysis

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Collagen Fibers in Crocodile Skin and Teeth:A Morphological Comparison Using Light and Scanning Electron Microscopy

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Journal of Bionic Engineering 2020年第4期17卷 669-676页

作者： Piotr krzysztof Szewczyk Urszula Stachewicz Metals Engineering and Industrial Computer Science and International Centre of Electron Microscopy for Materials Science AGH University of Science and TechnologyKraków 30-059Al.Mickiewicza 30Poland

Collagen is one of the most versatile tissues of living organisms that comes in many shapes and sizes,providing functions ranging from tissue matrix through,ligament formation up to enabling mineralization in *** detailed light microscopy and Scanning Electron Microscopy(SEM)observations conducted in this study,allowed us to investigate morphology,sizes and crimp patterns of collagen fibers observed in crocodile skin and ***,the microscopy study revealed that although two completely different tissues were investigated,many similarities in their structure based on collagen fibers were *** type I is present in crocodile skin and teeth,showing the flexibility in naturally constructed tissues to obtain various *** crimp size investigation of collagen fibers confirmed experimentally the theoretical 67 nm D-periodicity expected for collagen type *** collagen in teeth provides a matrix for crystal growth and in the skin provides flexibility and is a precursor for corneous ***,these observations of the collagen in the skin and tooth structure in crocodiles play an important role in designing biomimetic materials with similar functions and properties.

关键词： crocodile skin collagen crimp fiber crocodile tooth SEM

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Assessment of tectonic control on the development of low mountains moderate relief in the Outer Carpathians(Southern Poland)

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Journal of Mountain Science 2020年第10期17卷 2297-2320页

作者： Janusz GODZIEK krzysztof GAIDZIK Faculty of Natural Sciences University of SilesiaBedzinska 6041-200 SosnowiecPoland Institute of Earth Sciences University of SilesiaBędzińska 6041-200 SosnowiecPoland

Inherited tectonic structures,ongoing tectonic deformation,and variations in relative rock uplift rates play an important role in conditioning the processes of relief *** influence among other factors,such as climate and lithology,can be quantified using landscape analysis,and geomorphometric indices,in *** usage of landscape analysis in recent years is increasing systematically due to the constant improvement of the digital elevation models and GIS software that significantly facilitate this *** this study,we aim to recognize the influence of tectonic structures and processes on relief development in the low mountains with moderate relief of the Sola River catchment in the Western Outer *** this end,we calculated geomorphometric indices(river longitudinal profile,stream-length gradient index,minimum bulk erosion,relief ratio,circulatory ratio,elongation ratio,and hypsometric integral)for the Sola River and its 47 sub-catchments using a 25-m spatial resolution Digital Terrain Elevation Data Level ***,we identified lineaments and knickpoints and correlated the computed results with local and regional fault networks,variations in lithology,and climate *** results indicate a significant impact of inherited tectonicstructures on the relief development of the Sola River catchment,i.e.,directions of principal ridges and valleys follow the orientation of main folds and faults recorded in this *** high values of minimum bulk erosion,river gradient,and streamlength gradient index allowed us to define two areas with higher relative uplift rates:1)the So?a Gorge and 2)the Beskid Zywiecki *** Outer Carpathians are generally considered as an area of low strain rate and low seismic ***,the possibility of neotectonic processes should be considered in geohazard *** bends in the direction of river valleys that do not correspond with changes in lithology could be

关键词： Tectonics Landscape analysis Relief development Geomorphometric indices Digital elevation model Outer Carpathians

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Performance analysis of IEEE 802.11 DCF networks

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第10期9卷 1309-1317页

作者： krzysztof SZCZYPIORSKI Józef LUBACZ Institute of Telecommunications Warsaw University of Technology Nowowiejska 15/19 Warsaw 00-665 Poland

This paper presents an analytical saturation throughput model of IEEE 802.11 DCF (distributed coordination function) with basic access in ad hoc mode. The model takes into account freezing of the backoff timer when a station senses busy channel. It is shown that taking into account this feature of DCF is important in modeling saturation throughput by yielding more accurate and realistic results than models known from literature. The proposed analytical model also takes into account the effect of transmission errors. All essential features of the proposed analytical approach are illustrated with numerical results. The presen-tation of the model is proceeded by an overview of approaches to IEEE 802.11 network performance evaluation presented in the literature.

关键词： IEEE 802.11 Distributed coordination function (DCF) CSMA/CA Modeling

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