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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

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

Towards electrochemical hydrogen storage in liquid organic hydrogen carriers via proton-coupled electron transfers

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Journal of Energy Chemistry 2022年第10期31卷 292-300,I0007页

作者： Hamid Ghorbani Shiraz Mikhail Vagin Tero-Petri Ruoko Viktor Gueskine krzysztof Karon Mieczystaw tapkowski Tobias Abrahamsson Thomas Ederth Magnus Berggren Xavier Crispin Laboratory of Organic Electronics Department of Science and Technology(ITN)Linkoping UniversitySE-60174 NorrkopingSweden Smart Photonic Materials Facuty of Engineering and Natural SciencesTampere UniversiyPBox 541.Tampere Fl-33101Finland Silesian University of Technology.Faculty of Chemistry Deparment of Physical Chemistry and Technology of PolymersM.Strzody 9.44-100 GliwicePoland dDepartment of Physics Chemistry and Biology(IFM)Linkoping UniversiySE-58183 LinkopingSweden

Green hydrogen is identified as one of the prime clean energy carriers due to its high energy density and a zero emission of CO_(2).A possible solution for the transport of H_(2)in a safe and low-cost way is in the form of liquid organic hydrogen carriers(LOHCs).As an alternative to loading LOHC with H_(2)via a two-step procedure involving preliminary electrolytic production of H_(2)and subsequent chemical hydrogenation of the LOHC,we explore here the possibility of electrochemical hydrogen storage(EHS)via conversion of proton of a proton donor into a hydrogen atom involved in covalent bonds with the LOHC(R)via a protoncoupled electron transfer(PCET)reaction:2nH^(+)+2ne^(-)+Rox■n H_(2)^(0)*** chose 9-fluorenone/fluorenol(Fnone/Fnol)conversion as such a model PCET *** electrochemical activation of Fnone via two sequential electron transfers was monitored with in-situ and operando spectroscopies in absence and in presence of different alcohols as proton donors of different reactivity,which enabled us to both quantify and get the mechanistic insight on *** possibility of hydrogen extraction from the loaded carrier molecule was illustrated by chemical activation.

关键词： Proton-coupled electron transfer Electrochemical hydrogen storage Hydrogen bonding agent Anion-radical Comproportionation

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

The potential of gene therapies for spinal cord injury repair:a systematic review and meta-analysis of pre-clinical studies

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Neural Regeneration Research 2023年第2期18卷 299-305页

作者： Catriona J.Cunningham Mindaugas Viskontas krzysztof Janowicz Yasmin Sani Malin EHåkansson Anastasia Heidari Wenlong Huang Xuenong Bo Institute of Medical Sciences School of MedicineMedical Sciences&NutritionUniversity of AberdeenAberdeenUK Centre for Neuroscience Surgery and TraumaBlizard InstituteBarts and the London School of Medicine and DentistryQueen Mary University of LondonLondonUK

Currently,there is no cure for traumatic spinal co rd injury but one therapeutic approach showing promise is gene *** this systematic review and meta-analysis,we aim to assess the efficacy of gene therapies in pre-clinical models of spinal cord injury and the risk of *** this metaanalysis,registe red at PROSPERO(Registration ID:CRD42020185008),we identified relevant controlled in vivo studies published in English by searching the PubMed,Web of Science,and Embase *** restrictions of the year of publication were applied and the last literature search was conducted on August 3,*** then conducted a random-effects meta-analysis using the restricted maximum likelihood estimator.A total of 71 studies met our inclusion crite ria and were included in the systematic *** results showed that overall,gene therapies were associated with improvements in locomotor score(standardized mean difference[SMD]:2.07,95%confidence interval[CI]:1.68-2.47,Tau^(2)=2.13,I^(2)=83.6%)and axonal regrowth(SMD:2.78,95%CI:1.92-3.65,Tau^(2)=4.13,I^(2)=85.5%).There was significant asymmetry in the funnel plots of both outcome measures indicating the presence of publication *** used a modified CAMARADES(Collaborative Approach to M eta-Analysis and Review of Animal Data in Experimental Studies)checklist to assess the risk of bias,finding that the median score was 4(IQR:3-5).In particula r,reports of allocation concealment and sample size calculations were *** conclusion,gene therapies are showing promise as therapies for spinal co rd injury repair,but there is no consensus on which gene or genes should be targeted.

关键词： animal models gene delivery meta-analysis regenerative medicine spinal cord injury systematic review viral vectors

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：磨削工艺评论外圆磨床研磨工序路径控制饲料粉碎研磨材料砂轮

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 分布式协调功能 CSMA/CA 基本存取机制

INVESTIGATION OF THE ATRP OF n-BUTYL METHACRYLATE USING THE Cu(I)/N,N,N',N",N"-PENTAMETHYLDIETHYLENETRIAMINE CATALYST SYSTEM

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Chinese Journal of Polymer Science 2004年第2期22卷 195-204页

作者： Kelly A. Davis krzysztof Matyjaszewski Center for Macromolecular Engineering Department of Chemistry Carnegie Mellon University 4400 Fifth Ave.Pittsburgh Pennsylvania 15213 USACenter for Macromolecular Engineering Department of Chemistry Carnegie Mellon University 4400 Fifth Ave.Pittsburgh Pennsylvania 15213 USA

The polymerization of n-butyl methacrylate was investigated using the Atom Transfer Radical Polymerization technique with CuBr and CuCl/N,N,N',N',N'-pentamethyldiethylenetriamine catalytic systems. Various combinations of catalyst systems and initiators were utilized in order to optimize the polymerization conditions and to obtain well-defined polymers (i.e. controlled molecular weights and low polydispersities). It has been found that the optimal initiator for this system is a chlorine-based initiator, when the catalyst used is a salt in conjunction with the N,N,N',N',N'- pentamethyldiethylenetriamine ligand. Bromine-based initiators tend to result in large amounts of initial termination, leading to polymers with less than ideal chain end functionality, even if CuCl is used as the species to invoke the halogen exchange. Additionally, the effects of the polymerization temperature, species and the initiator structure were determined.

关键词： ATRP Atom transfer radical polymerization Controlled/living radical polymerization Butyl methacrylate Pentamethyldiethylenetriamine

Design of a device for precision shaping of grinding wheel macro-and micro-geometry

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Journal of Central South University 2012年第1期19卷 135-143页

作者： krzysztof NADOLNY Wojciech KAPLONEK Department of Production Engineering Faculty of Mechanical EngineeringKoszalin University of TechnologyRacIawicka 15-1775-620 KoszalinPoland Subject Group of Metrology and Quality Faculty of Mechanical EngineeringKoszalin University of TechnologyRacIawicka 15-1775-620 KoszalinPoland

The selected modifications to the construction of grinding wheels were described which facilitate an increase in the material removal rate(grinding wheels with conic chamfer and grinding wheels with microdiscontinuities on the active surface).Using these background details,a suggested thesis was put forward regarding the need to develop a device which will allow for the shaping of the macrogeometry of the grinding wheel(cylindrical and conical surfaces) and the microdiscontinuities within the dressing operation *** device was presented and prepared in two functional variants(horizontal and vertical mounting of the motor),then a prototype was *** example of the grinding wheel active surface,shaped by using this device,was also *** theoretical analysis and experimental verification performed determine that the error of shaping the conic chamfer angle within the range of 0-1.5o,using the developed device,is approximately ±3%.

关键词：成型砂轮精密设备设计几何微观宏观表面活性材料去除率