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research in Astronomy and Astrophysics 2018年第8期18卷 83-88页

作者： Anna Tatarnikova Marina Burlak Eugene Kolotilov Natalia Metlova Victor Shenavrin Sergei Shugarov Taisija Tarasova Andrey Tatarnikov Sternberg Astronomical Institute Moscow State UniversityMoscow 119234Russia Astronomical Institute of the slovak Academy of Sciences 05960 Tatranska LomnicaSlovakia Federal State Budget Scientific Institution"Crimean Astrophysical Observatory of RAS" Nauchny298409Russia

A new set of low-resolution spectral and UBVJHKL-photometric observations of the symbi- otic nova PU Vul is presented. The binary has been evolving after its symbiotic nova outburst in 1977 and now it is in the nebular stage. It is found that the third orbital cycle （after 1977） was characterized by great changes in associated light curves. Now, PU Vul exhibits a sine-wave shape in all the light curves （with an amplitude in the U band of about 0.7 mag）, which is typical for symbiotic stars in the quiescent state. Brightness variability due to pulsations of the cool component is now clearly visible in the VRI light curves. The amplitude of the pulsations increases from 0.5 mag in the V band to 0.8 mag in the I band. These two types of variability, as well as a very slow change in the physical parameters of the hot component due to evolution after the outburst of 1977, influence the spectral energy distribution （SED） of the system. The variability of emission lines is highly complex. Only hydrogen line fluxes vary with orbital phase. An important feature of the third orbital cycle is the first emergence of the OVI, 6828A Raman scattering line. We determine the temperature of the hot component by means of the Zanstra method applied to the He II, 4686A line. Our estimate is about 150000 K for the spectrum obtained near orbital maximum in 2014. The VO spectral index derived near pulsation minimum corresponds to M6 spectral class for the cool component of PU Vul.

关键词： binaries symbiotic - novae - cataclysmic variables - stars individual (PU Vul)

EPR Study of the Thermal Decomposition of Transannular Peroxide of Anthracene

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International Journal of Organic Chemistry 2011年第2期1卷 37-40页

作者： Lubomir Lapcik Jr. Barbora Lapcikova Andrej Stasko Centre of Polymer Systems Faculty of TechnologyTomas Bata UniversityZlinCzech Republic slovak Technical University Bratislava Faculty of Chemical&Food TechnologyBratislavaSlovak Republic

Thermal decomposition of transannular peroxide of anthracene (POA) (or 9,10-epidioxido anthracene) was studied by means of electron paramagnetic resonance spectroscopy (EPR) in the solid as well as in the liquid phases. Decomposition process proceeds via cleavage of the O-O bridge of the POA molecule, generating thus an alcoxy intermediate radical. Its concentration increases to a certain equilibrium stage during the time scale of the experiment. EPR spectra in the solid state were of the singlet type at the temperatures over 350 K, a doublet like anisotropic spectra were measured at the room temperature, both having g-value 2.0033. EPR spectrum from POA decomposed in benzene indicates four protons with higher (2aH = 0.305 mT, 2aH = 0.335 mT) and four protons with a lower (2aH = 0.075 mT, 2aH = 0.105 mT) splitting constants, corresponding well the radical expected after cleavage of O-O bridge.

关键词： Endoperoxide Anthracene Free Radicals EPR Decomposition Kinetics

Cyclical Elliptical Pedal Surfaces

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Journal of Mathematics and System Science 2011年第1期1卷 1-6页

作者： Eva Baranova Department of Aerodynamics and Simulation Technical University in Kosice Kosice 041 21 Slovak Republic

Intensive use of geometrical modelling started with the development of computer graphics and CAD/CAM technologies, comprising a wide area of mathematical disciplines. Geometrical modelling is a synthesis of the geometry and computer graphics, which enable us to develop complex mathematical models that would be rather difficult to display without using a computer. The author recognizes two basic methods of research of geometrical models, synthetic and analytic. The synthetic method makes use of geometrical constructions and in the analytic method geometrical objects are characterized by numerical data. The author uses these methods in this contribution. The aim of this research is to show central cyclides （Dupin＇s cyclides） as a special kind of the cyclical elliptical pedal surfaces. Firstly, applying the method of synthetic geometry, a new class of such surfaces in the 3-dimensional Euclidean space （model of the projective space） is defined. The geometrical construction of these surfaces is dependent on the given ellipse and the position of the pole P. It is the point at which the pencil of perpendicular planes passes to the plane of the ellipse, wherein the generating circles of the surface are lying. The parametric equations of the cyclical elliptical surface are derived applying the method of analytic geometry. The author classifies the surfaces according to the number of generating circles with a zero radius. The evolute of the ellipse divides the plane of the ellipse into two areas, Ω1 and Ω2. The shape of the surface depends on the position of the pole P in the areas of Ω1 and Ω2. The surface can have 4, 3 or 2 circles with a zero radius. The author then describes the relationship between these surfaces and the Dupin＇s cyclides, obtained in the case when the pole P is the point on the major axis of the ellipse. Finally, the transformation of these surfaces is shown by changing of the orthonormal base in the parameterization of the generating circles of the sur

关键词： Cyclical elliptical pedal surfaces creation classification Dupin's cyclides.

Perceived Injustices in Forest Policy Interventions are Causes of Forest Resources Degradation and Loss in Ghana: A Review

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Open Journal of Forestry 2021年第3期11卷 171-191页

作者： Richard Kyere-Boateng Michal V. Marek Mikuláš Huba Tatiana Kluvankova Department of Spatial Planning Institute of Management Slovak University of Technology in Bratislava Vazovova 5 812 43 Bratislava Slovakia Department of the Human Dimensions of Global Change Global Change Research Institute Czech Academy of Sciences Brno Bělidla 986/4a 603 00 Brno Czech Republic Department of Geographic Science University of Energy and Natural Resources (UENR) 214 Sunyani Ghana slovakGlobe Institute of Management Slovak University of Technology in Bratislava Vazovova 5 812 43 Bratislava Slovakia slovakGlobe: Institute of Forest Ecology slovak Academy of Sciences Institute of Management Slovak University of Technology Vazovova 5 812 43 Bratislava Slovakia

Forests provide diverse co-benefits, including livelihoods enhancement, poverty alleviation, and biodiversity conservation and ecosystem services such as climate mitigation. Consequently, Ghana has embraced several global, regional, national, and local forest policy interventions to safeguard its forest resources’ sustainable management. However, the forest policy interventions have not adequately addressed the co-benefits issues of forest resources leading to several forest illegalities that drive forest resources degradation and loss. These forest policies and interventions on the ground primarily favour carbon stocks enhancement and sequestration activities for carbon mitigation purposes compared to the benefits, access and rights that forest-dependent people and communities are supposed to derive from forest resources. These perceived injustices in the access and distribution of forest resources have culminated into all forms of forest illegalities driving Ghana’s forest resources into massive degradation and loss. Currently, Ghana is experiencing a 2% rate of annual deforestation and forest degradation, which translates into approximately 135,000 ha/year of forest cover loss due to anthropogenic causes. Our review is based on relevant and critical forest documents, and scientific peer-reviewed papers on Ghana’s forest policy interventions and dynamics recently published. The information gathered enabled us to highlight the perceived injustices in the forest policy interventions and their

关键词： Ghana Forest Policy Intervention Deforestation and Biodiversity Degradation Climate Mitigation Sustainability

Analytic Invariant Curves for an Iterative Equation Related to Ricker-type Second-order Equation

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Acta Mathematica Sinica,English Series 2021年第7期37卷 1041-1052页

作者： Hou Yu ZHAO Michal FECKAN School of Mathematics Chongqing Normal UniversityChongqing 401331P.R.China Department of Mathematical Analysis and Numerical Mathematics Comenius University in BratislavaMlynska dolina84248 BratislavaSlovakia Mathematical Institute of slovak Academy of Sciences Stefanikova 4981473 BratislavaSlovakia

In this paper,we consider the existence of analytic invariant curves of an iterative equation f(f(x))=xea-x-f(x)which arises from Ricker-type second-order *** reducing the equation with the Schr?der transformation to an auxiliary equation,the author discusses not only that the parameter at resonance,i.e.,at a root of the unity,but also the parameter near resonance under the Brjuno condition.

关键词： Difference equation invariant curves analytic solution small divisor

The Effect of Different Diet on Saliva

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Spectral Analysis Review 2017年第4期5卷 37-48页

作者： Vladimíra Tomecková Kristína Krajcíková Slavomíra Dolinská Vladimír Komanický Tomás Samuely Department of Medical and Clinical Biochemistry Faculty of MedicinePavol Jozef Safárik University in KosiceKosiceSlovak Republic Institute of Physics Faculty of SciencePavol Jozef safárik University in KosiceKosiceSlovak Republic

The aim of this scientific research was to study the influence of various diets (ketogenic, low carb, mixed) on teeth and saliva structure of healthy individuals. The health condition of teeth and the influence of diet (sweets, water intake) were investigated using the questionnaires which were statistically processed by descriptive and inductive statistics. Saliva was examined using synchronous fluorescent fingerprint (SFF) and atomic force microscopy (AFM). The statistical evaluation of answers of respondents using the questionnaires about intake of sweets in their diet showed significant influence of sugars on formation of tooth decay of diet. The intake of water (volume and frequency) did not show significant influence on formation of tooth decay. Endogenous fluorescence and surface structure of saliva differed in healthy subjects with different diet. The most organized surface structure showed low carb diet (without crystals). The least organized surface structure showed ketogenic diet with the big crystals (1 - 2 μm). Untraditional methods (SFF and AFM) enable the new, sensitive and quick analysis of the mixture of saliva. Saliva of individuals with low carb diet showed the most organized structure. Low content of sugar in diet is important possibility of the prevention before dental carries.

关键词： Low Carb Diet Mixed Diet Ketogenic Diet Saliva Synchronous Fluorescence Fingerprint Atomic Force Microscopy

Potentials of a Place as Leaders for Prioritizing the Adjustment of Public Spaces within a Hierarchy

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Journal of Civil Engineering and Architecture 2016年第3期10卷 327-334页

作者： Alena Bindzarova Institute of Urban Design and Planning Faculty of Architecture Slovak University of Technology Bratislava 81245 Slovakia

The article gives a view over a part of a research that has been started on public spaces as a shared wealth of different qualities and uses. Introduction explores the capital of slovakia a little bit in the sense of urban structure and historical consequences. The issue is currently solved by several members （academics, officials, NGOs （non-governmental organizations）） focusing on the same thing from slightly different aspects. Therefore, qualities and characteristics of an open space are put into closer look in the main text body part. Single tools working with individual features describe the up-to-date situation in the Bratislava city center. It is assumed that they could be used for whole city and other cities as well, what would bring an overall look at towns and cities in slovakia. Features and findings are expressed in map and in simplified graphic schemes. Findings include mutual effects and consequences between role of a space in the city as a cultural phenomenon, its physical surrounding and people flowing daily through it. Finally, advices and prioritization could be formed for the city itself as a self-governing subject to improve its ＂inner-outer＂ qualities.

关键词： Public space quantificators urban design

Diff erences in pigment circadian rhythmicity in greenand red-leafed tree species in the sun and shade

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Journal of Forestry research 2023年第3期34卷 693-704页

作者： Ermes Lo Piccolo Giulia Lauria Giulia Bongi Lucia Guidi Marian Brestic Damiano Remorini Rossano Massai Marco Landi Department of Agriculture Food and EnvironmentUniversity of PisaVia del Borghetto 8052124 PisaItaly Centre for Climate Change Impact CIRSECUniversity of PisaVia del Borghetto 8052124 PisaItaly Department of Plant Physiology Slovak University of AgricultureA.Hlinku 2Nitra 94976Slovakia

Light fl ux and quality are crucial factor for setting endogenous plant circadian *** the daily rhythmicity of leaf chlorophyll content is an eff ective method to monitor the plant physiological endogenous clock in response to environmental signals such as light availability/***,we used a leaf-clip sensor to monitor diurnal rhythms in the content of chlorophyll and fl avonoids such as fl avonols and anthocyanins in three green-(Ailanthus altissima,Tilia platyphyllos and Platanus×acerifolia)and two red-leafed(Acer platanoides *** King and Prunus cerasifera ***)tree species,adapted to sun(L)or shade(S).Signifi cant diff erences in chlorophyll content(Chl)and its variations during the day were observed among treatments in all the analyzed species.S-plants had more Chl than L-plants irrespective of leaf color,and Chl variations were more distinct during the day than in *** particular,contents were lowest in the morning(9:00)and in the middle of the day(at 12:00 and 15:00),and the highest at dusk(21:00).The less evident trends in Chl variation in L-plants were attributed to a decrease in Chl content in high light,which likely masked any increases in the shaded counterparts during the *** fl avonol levels did not vary no notably during the *** sun-exposed red leaves,anthocyanins partially screened mesophyll cells from incident light,and its levels were similar to the Chl dynamics in the shaded *** study provides new bases for further work on endogenous rhythms of plant pigments and improves our understanding of plant physiology in the context of day/night rhythmicity.

关键词： Anthocyanins Chlorophylls Circadian clock Flavonols Shade syndrome

The Impact of Foreign Bank Strategies on the Behavior and Performance of Czech and slovak Banks in the Financial Crisis

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Journal of Modern Accounting and Auditing 2013年第7期9卷 988-996页

作者： JosefTauser Martin Sroka Pavel Zambersky University of Economics Prague Czech Republic IBM Integrated Supply Chain Bratislava Slovak Republic

In this paper, the authors analyze the impact of the specific ownership structure of the banking sector in Czech and slovakia on the performance and applied strategies of particular banks during times of crisis. Did the multinational banks pursue a coherent regional strategy to cope with the risks resulting from the crisis, or did they focus on finding local solutions？ The aim of this paper is to find answers to these questions. A case study is going to be used as a basic research method. Two members （slovak and Czech） of four multinational banking groups are examined in the crisis year 2009, whereby both a qualitative analysis of the annual reports regarding strategic business or risk management decisions and a comparative quantitative analysis of selected financial data and risk indicators are employed. The authors have found that Czech and slovak banks generally tried to follow the main strategic directions given by their parent banks during the financial crisis. However, particular financial results and risk profiles of respective subsidiaries of multinational banks still differ because of market factors specific to the different countries in which the subsidiaries are located.

关键词： banks' strategies banks' performance multinational banks financial crisis