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Forest Disturbance Enhanced the Activity of Epedaphic Collembola in Windthrown Stands of the High Tatra Mountains

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Journal of Mountain Science 2014年第2期11卷 449-463页

作者： Veronika URBANOVIOVá Dana MIKLISOVá Lubomír ková Institute of Biology and Ecology Faculty of Science P.J. Safárik UniversityMoyzesova 11 Kosice 04001 Slovakia Institute of Parasitology Slovak Academy of SciencesHlinkova 3 Kosice 04001 Slovakia

The study aimed to assess the response of ep- and hemiedaphic Collembola communities(activity, richness, community structure) to a disturbance, the subsequent management regime and to the season(summer, winter) in a High Tatra Mountains spruce forest destroyed by a *** and clear-cut resulted in an initial increase in the activity of Collembola inhabiting open areas,opportunistic or generalist species, while forest specialists diminished in numbers or *** results indicated that treatment with nonextracted fallen trees(NEX) provided a better chance for forest species to survive compared with their survival in open habitats of extracted(EXT) and wildfire(FIR) treatments. Great species' potential of NEX treatment was indicated by Chao2 estimator and activity/species rarefaction curves. Communities of NEX treatment were more similar to the reference(REF) treatment, documented by ordination and cluster analyses. Thus, leaving fallen timber after a windthrow to natural process of succession is suitable for survival of forest species and maintenance of diversity in forests restoration than timber *** structure in wildfire(FIR) stands was the most dissimilar to the other treatments. Most of the species trapped in this treatment belonged to hemiedaphic life forms, while the activity of larger epedaphic species diminished. In contrast, the highest number of trapped Collembola in EXT treatment was connected with the larger-bodied epigeic species with fast dispersal ability. The trapping period affected both the number of individuals and species richness;Collembola activity and species diversity in the individual treatments were lower in winter compared with the summer period. Several species increased activity during the winter period, namely Folsomia penicula, Friesea mirabilis, F. truncata, Hypogastrura socialis and Protaphorura aurantiaca.

关键词：森林物种跳虫高塔干扰物种多样性社会结构木材采伐物种丰富度

Extreme matter compression caused by radiation cooling effect in gigabar shock wave driven by laser-accelerated fast electrons

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Matter and Radiation at Extremes 2021年第2期6卷 1-7页

作者： S.Yu.Gus’kov P.A.Kuchugov G.A.Vergunova P.N.Lebedev Physical Institute of the Russian Academy of Sciences MoscowRussia Keldysh Institute of Applied Mathematics of the Russian Academy of Sciences MoscowRussia

Heating a solid material with laser-accelerated fast electrons is a particularly useful method for generating a plane powerful shock wave with a pressure of several hundred or even thousands of Mbar in the *** the front of such a powerful shock wave,dense plasma is heated to a temperature of several ***,a high rate of radiation energy loss occurs even in low-Z *** this paper,the strong compression of matter due to radiation cooling in a Gbar shock wave driven by fast electrons is studied using both computational and theoretical *** is shown that the effect of radiation cooling leads to compression of matter in the peripheral region of the shock wave to a density several times greater than the density at its *** a solid material by a petawatt flux of laser-accelerated fast electrons offers the opportunity to surpass the gigabar pressure level of plane shock waves generated by the impact of laser-accelerated *** pressures of about 100 Gbar can be achieved under laboratory conditions only when a spherical target is imploded under the action of a terawatt laser pulse.

关键词： laser shock wave

Impact of Natural Oil-Based Recycled Polyols on Properties of Cast Polyurethanes

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Journal of Renewable Materials 2018年第7期6卷 697-706页

作者： Hynek Beneš Aleksandra Paruzel JiříHodan Olga Trhlíková Institute of Macromolecular Chemistry AS CR v.v.i.Heyrovsky Sq.216206 Prague 6Czech Republic

In this study, castor oil, rapeseed oil and medium chain triglycerides of coconut oil, were transesterified bymeans of 2-ethyl-2-hydroxymethyl-1,3-propanediol (trimethylolpropane) and consequently used to convertpolycarbonate waste from end-of-life vehicles into liquid polyols. The prepared recycled polyols, composeduniquely of renewable and recycled components, had a hydroxyl number of ca. 250 mg KOH·g−1. They weresuccessfully applied as 100% replacement of a virgin polyol for preparation of solid crosslinked polyurethanes(PU) by solvent-free casting. The produced rigid cast PU exhibited the main transition temperature rangingfrom 44°C to 53°C, the hardness value from 46 to 61 Shore D and the beneficial low water absorption (0.4-0.5wt.%). The PU network structure was highly influenced by the presence of aromatic structures ofpolycarbonate-units and fatty acid compositions. A suitable selection of natural oil thus enabled to adjustthermo-mechanical properties and promote excellent optical transparency of the produced PU.

关键词： Natural oil cast polyurethane bio-based polycarbonate waste recycling

Current State and Development of the Soil Health Index in Localities with Various Soil-Climatic Conditions in the Slovak Republic

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Journal of Geoscience and Environment Protection 2022年第6期10卷 1-11页

作者： Jarmila Makovníková Boris Pálka Stanislav Kološta National Agricultural and Food Centre/Soil Science and Conservation Research Institute Bratislava Regional Station Banská Bystica Slovakia Faculty of Ecomonics Matej Bel University Banská Bystrica Slovakia

The aim of the study was to assess the current state and development of the Soil Health Index (SHI) at 13 localities with various soil-ecological conditions in the Slovak Republic. The SHI was developed using a minimum soil data set, physical and chemical soil parameters in combination with environmental parameters (land use, gradients). The SHI is one numerical value accumulates information about the state of soil health and its ability to provide soil functions and thus ecosystems in the optimal range. The highest SHI values were determined at model localities used as arable land (Haplic Chernozem, Fluvisol) located in a warm climate at altitudes up to 200 meters above sea level. Ecosystems with very low and low value are mostly grasslands with mildly cold climate (Cambisol) and considerable slope, agroecosystem on low organic matter (Arenosol). Arable ecosystem SHI is also reduced in areas of geochemical anomalies and areas with anthropogenic load, where there is a higher content of risk elements. The SHI changes are mainly the result of changes in dynamic indicators such as soil response and soil bulk density.

关键词： Soil Health Agroecosystem Services Soil Parameters Minimum Soil Data Set

On Non-normal Arc-Transitive 4-Valent Dihedrants

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Acta Mathematica Sinica,English Series 2010年第8期26卷 1485-1498页

作者： István kovCS Botjan KUZMAN Aleksander MALNI FAMNIT University of Primorska PeF University of Ljubljana IMFM University of Ljubljana

Let X be a connected non-normal 4-valent arc-transitive Cayley graph on a dihedral group Dn such that X is bipartite, with the two bipartition sets being the two orbits of the cyclic subgroup within Dn. It is shown that X is isomorphic either to the lexicographic product Cn[2K1] with n 〉 4 even, or to one of the five sporadic graphs on 10, 14, 26, 28 and 30 vertices, respectively.

关键词： Cayley graph arc transitivity dihedral group

Change of photosensitizer fluorescence at its diffusion in viscous liquid flow

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Journal of Innovative Optical Health Sciences 2016年第2期9卷 25-30页

作者： Valeriya S.Maryakhina Vyacheslav V.Gun'kov Orenburg State University 13 Pobedy st. Orenburg 460018Russia

In this paper,the mathematical model of distribution of the injected compound in biological liquid flow has been *** is considered that biological liquid contains a few phases such as water,peptides and *** injected compound(for example,photosensitizer)can interact with peptides and *** the time,viscosity of the biological liquid depends on pathology present in *** obtained distribution of the compound connects on changes of its fluorescence spectra which are registered during fluorescent diagnostics of *** is obtained that the curves do not have monotonic *** is a sharp curves decline in the first few seconds after *** of curves rises after *** is especially pronounced for wavelength 590 nm and 580 nm(near the"transparency window"of biological tissues).Time of inflection point shifts from 8.4 s to 6.9 s for longer ***,difference between curves is little for di®erent viscosity means of the biological ***,additional pathology present in organism does not impact to the results of in vivo biomedical investigations.

关键词： Fluorescence diffusion biomedical diagnostics photosensitizer viscosity

Impact of Fast-Growing Trees Planting on Degraded Land from Perspectives of Ecosystem Services—Case Study from Slovakia

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Journal of Geoscience and Environment Protection 2022年第11期10卷 140-150页

The aim of the study was to assess the effect of natural phytoremediation, impact of growing fast-growing trees on contaminated agricultural land on ecosystem services using a Matrix evaluation system. The Matrix system is a table that links an ecosystem to its potential to provide ecosystem services. To determine the monetary price of natural capital for the provision of ecosystem services, we chose the value transfer method, based on which it is possible to assign a price (1 point = 40.7 EUR) to point values. Monitoring of the study site Kuchyňa (Mollic Fluvisol) is running since year 2010. The fast-growing willow was planted (between 2006 to 2018 year) on an area of about 43 hectares. During the monitoring of soil parameters, we observed a slight decrease in the value of the active soil reaction, a negative trend in the content of available phosphorus and a positive trend in the development of the total content risk elements in the soil. The phytoremediation ability of willow regarding risk elements was manifested by an increase in the value and price of production and regulatory ecosystem services at the monitored location. The price of natural phytoremediation of fast-growing willow on the given area was 218762.5 EUR for production services and 171509.8 EUR for regulatory services.

关键词： Ecosystem Services Soil Parameters Fast Growing Trees

Complications in children with percutaneous endoscopic gastrostomy (PEG) placement

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World Journal of Pediatrics 2019年第1期15卷 12-16页

作者： Brigitta Balogh Tamás kovács Amulya Kumar Saxena Division of Pediatric Surgery Department of PediatricsUniversity of SzegedKorányi fasor 14-15Szeged 6725Hungary Department of Pediatric Surgery Chelsea Children's HospitalChelsea and Westminster NHS Fdn TrustImperial College LondonLondonUK

Introduction The aim of this study was to analyze the complication rates and mortality in association with different operative techniques of percutaneous endoscopic gastrostomy (PEG),age,underlying diseases and other risk ***,analysis of the indications of PEG insertion and the underlying comorbidities was also *** This study performs a literature analysis of PEG-related complications in *** was searched on PubMed(R) (1994-2017) using terms 'percutaneous endoscopic gastrostomy','complications','mortality' and 'children'.Results Eighteen articles with 4631 patients were *** mean age was 3 years (0-26 years).Operative techniques were:pull technique in 3507 (75.7%),1 stage PEG insertion in 449 (9.7%),introducer technique in 435 (9.4%),image-guided technique in 195 (4.2%) and laparoscopic-assisted PEG in 45 (1.6%).Most frequent indications for PEG insertion were dysphagia (n =859,32.6%),failure to thrive (n =723,27.5%) and feeding difficulties (n =459,17.4%).Minor complications developed in n 1518 patients (33%),including granulation (n =478,10.3%),local infection (n =384,8.3%) and leakage (n =279,6%).In 464 (10%) patients,major complications occurred;the most common were systemic infection (n =163,3.5%)and cellulitis (n =47,1%).Severe complication like perforation occurred in less than 0.3%.Patients with lethal outcomes (n =7,0.15%) had severe comorbidities;and the cause of mortality was sepsis in all *** or young age did not affect complication *** with ventriculoperitoneal (VP) shunt had higher risk of major *** high-risk patients,laparoscopic-assisted PEG insertion had less major and severe complication than traditional pull *** PEG is a safe operative technique;although minor complications are relatively common and occur in up to 1/3 of patients,there is a fairly low rate of severe ***-thirds of PEG patients have at least one ***

关键词： Children Complications Percutaneous endoscopic gastrostomy

Species traits and shoot-root biomass allocation in 20 dry-grassland species

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Journal of Plant Ecology 2018年第2期11卷 273-285页

作者： Iveta Husáková Jacob Weiner Zuzana Münzbergová Department of Botany Faculty of ScienceCharles UniversityBenátská2CZ-12801 PragueCzech Republic Institute of Botany Academy of Sciences of the Czech RepublicZámek 1CZ-25243 PrůhoniceCzech Republic Department of Plant and Environmental Sciences University of CopenhagenThorvaldsensvej 40DK-1871 FrederiksbergDenmark

Aims A plant has a limited amount of resources at any time and it allo-cates them to different *** spite of the large number of previous studies on allocation patterns within single species,knowledge of general patterns in species allocation is still very *** is because each study was done in different condi-tions using different methodology,making generalization *** investigate intraspecific above-versus below-ground biomass allocation among individuals across a spectrum of dry-grassland plant species at two different developmental stages and ask whether allocation is age-and species specific,and whether differences among species can be explained by their life-history traits and *** We collected data on above-and below-ground biomass of seedlings and adult plants of 20 species from a common garden *** analysed data on shoot-root biomass allocation allometrically and studied the relationship between the allometric exponents(slopes on log-log scale),species life-history traits and phylogenetic *** Findings We found isometric as well as allometric patterns of biomass alloca-tion in the studied *** and adult individuals of more than half of the species differed in their above-versus below-ground biomass allometric *** and adult individuals of the remaining species differed in their allometric coefficients(inter-cepts).Annual species generally allocated proportionally more to above-than below-ground biomass as seedlings than as adults,whereas perennial species showed the opposite *** life-history traits,such as plant life span,age of first flowering,month in which the species begin flowering and specific leaf area were much more important in explaining differences in shoot-root allometry among species than were phylogenetic *** suggests that allocation patterns vary greatly among closely related species but can be predicted based on species life-hi

关键词： above-ground biomass below-ground biomass allometry isometry seedling adult plant life-history traits phylogenetic relatedness root-shoot ratio