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Geochronology of the Neogene calc-alkaline intrusive magmatism in the "Subvolcanic Zone" of the Eastern Carpathians (Romania)
Zoltán Pécskay, Ioan Seghedi, Marinel Kovacs, Alexandru Szakács, , Alexandrina Fül p
Geologica Carpathica , 2009, DOI: 10.2478/v10096-009-0012-5
Abstract: The Poiana Botizei- ible -Toroiaga-Rodna-Bargau intrusive area (PBTTRB), northwest Romania, known as the "Subvolcanic Zone", is located between the Gutai (NW) and Calimani (SE) volcanic massifs. It consists of rocks displaying a wide range of compositions and textures: equigranular or porphyritic with holocrystalline groundmass (gabbro-diorites, diorites, monzodiorites and granodiorites), and/or porphyritic with fine holocrystalline or glassycryptocrystalline groundmass, similar with effusive rocks: basalts, basaltic andesites, andesites, dacites and rhyolites. The time-span of intrusive rocks emplacement is similar with the nearest calc-alkaline volcanic rocks from Gutai (NW) and Calimani (SE) massifs. They are represented by stocks, laccoliths, dykes and sills typical for an upper crustal intrusive environment. In the absence of biostratigraphic evidence, a comprehensive K-Ar study of intrusive rocks using whole rock samples, groundmass and monomineral fractions (biotite, hornblende) has been carried out in order to understand the magmatic evolution of the area. The oldest K-Ar ages recorded in the analysed rocks are close to 11.5 Ma and magmatism continued to develop until about 8.0 Ma. The inception of intrusion emplacement in the PBTTRB is coeval with intrusive activity spatially related to volcanism within the neighbouring Gutai and Calimani massifs. However, its culmination at ca. 8 Ma ago is younger than the interruption of this activity at ca. 9.2 Ma in Gutai and Calimani Mts where intrusive activity resumed for ca. 1 Myr. These circumstances strongly suggest that the geodynamic evolution of the area controlled the development of both volcanic and intrusive activity and their reciprocal relationships. The overall geological data suggest that in the PBTTRB intra-lithospheric transpressional-transtensional tectonic processes controlled the generation and emplacement of intrusive bodies between ca. 12-8 Ma.
On the age of the Dej Tuff, Transylvanian Basin (Romania)
Alexandru Szakács, , Zoltán Pécskay, Lóránd Silye, Kadosa Balogh, Daniela Vlad, Alexandrina Fül p
Geologica Carpathica , 2012, DOI: 10.2478/v10096-012-0011-9
Abstract: The Dej Tuff is an important stratigraphic marker in the Transylvanian Basin. However, its Early Badenian age is known only on biostratigraphical grounds so far. A number of radiometric dating techniques including K-Ar, Ar-Ar and fission-track have been used in order to constrain more precisely its age, allowing the calibration of the Transylvanian Basin's evolutionary models. Although individual dating methods could not provide a unique, reliable and accurate radiometric age, comparison and evaluation of multiple methods gives 14.8-15.1 Ma as the most likely formation age of the Dej Tuff.
Developing Stability Control Theories for Agricultural Transport Systems
Tamás Szakács
Acta Polytechnica Hungarica , 2010,
Abstract: The design and management of agricultural transport systems is facing a seriesof challenges. The goals of increasing vehicle mobility and reducing soil stress have alwaysbeen in the center of attention. Involving trailer wheels in the production of pulling forcecould be beneficial in both cases. In this way, the mobility of the transport system could besecured even in heavy soil conditions, and the soil damage could be reduced as well.Despite the potential advantages, trailer protrusion is not currently practical. The reasonfor this is the lack of proper safety measures. The origin of this problem is the forcegenerated by the trailer protrusionacting on the drawbar, which can bring the tractor intoan unstable state, causing the tractor to roll over or the vehicle train to jack-knife. Toavoid such accidents, a control system must be developed which can recognize thebeginning of unstable vehicle behavior and either by warning or intervention help tomaintain the stable state of the vehicle.The goals of this paper can be summarized as follows:– To introduce a computer simulation model of an agricultural transport vehicle-parkconsisting of different dynamical models of tractors and trailers. The aim of this modelparkis to perform stability analysis of tractor – propelled axle trailer vehiclecombinations.– To introduce stability criteria equations for future stability control programs which candetermine different unstable states, and by interaction can re-stabilize the vehiclecombinations.
On the graph condition regarding the $F$-inverse cover problem
Nóra Szakács
Mathematics , 2015, DOI: 10.1007/s00233-015-9713-5
Abstract: In their paper titled "On $F$-inverse covers of inverse monoids", Auinger and Szendrei have shown that every finite inverse monoid has an $F$-inverse cover if and only if each finite graph admits a locally finite group variety with a certain property. We study this property and prove that the class of graphs for which a given group variety has the required property is closed downwards in the minor ordering, and can therefore be described by forbidden minors. We find these forbidden minors for all varieties of Abelian groups, thus describing the graphs for which such a group variety satisfies the above mentioned condition.
Inverse monoids and immersions of 2-complexes
John Meakin,Nóra Szakács
Mathematics , 2014, DOI: 10.1142/S0218196715400123
Abstract: It is well known that under mild conditions on a connected topological space $\mathcal X$, connected covers of $\mathcal X$ may be classified via conjugacy classes of subgroups of the fundamental group of $\mathcal X$. In this paper, we extend these results to the study of immersions into 2-dimensional CW-complexes. An immersion $f : {\mathcal D} \rightarrow \mathcal C$ between CW-complexes is a cellular map such that each point $y \in {\mathcal D}$ has a neighborhood $U$ that is mapped homeomorphically onto $f(U)$ by $f$. In order to classify immersions into a 2-dimensional CW-complex $\mathcal C$, we need to replace the fundamental group of $\mathcal C$ by an appropriate inverse monoid. We show how conjugacy classes of the closed inverse submonoids of this inverse monoid may be used to classify connected immersions into the complex.
On F-inverse covers of finite-above inverse monoids
Nóra Szakács,Mária B. Szendrei
Mathematics , 2015,
Abstract: Finite-above inverse monoids are a common generalization of finite inverse monoids and Margolis--Meakin expansions of groups. Given a finite-above $E$-unitary inverse monoid $M$ and a group variety $\mathit{U}$, we find a condition for $M$ and $\mathit{U}$, involving a construction of descending chains of graphs, which is equivalent to $M$ having an $F$-inverse cover via $\mathit{U}$. In the special case where $\mathit{U}=\mathit{Ab}$, the variety of Abelian groups, we apply this condition to get a simple sufficient condition for $M$ to have no $F$-inverse cover via $\mathit{Ab}$, formulated by means of the natural parial order and the least group congruence of $M$.
Assessing soil carbon stocks under pastures through orbital remote sensing
Szakács, Gabor Gyula Julius;Cerri, Carlos Clemente;Herpin, Uwe;Bernoux, Martial;
Scientia Agricola , 2011, DOI: 10.1590/S0103-90162011000500010
Abstract: the growing demand of world food and energy supply increases the threat of global warming due to higher greenhouse gas emissions by agricultural activity. therefore, it is widely admitted that agriculture must establish a new paradigm in terms of environmental sustainability that incorporate techniques for mitigation of greenhouse gas emissions. this article addresses to the scientific demand to estimate in a fast and inexpensive manner current and potential soil organic carbon (soc) stocks in degraded pastures, using remote sensing techniques. four pastures on sandy soils under brazilian cerrado vegetation in s?o paulo state were chosen due to their soc sequestration potential, which was characterized for the soil depth 0-50 cm. subsequently, a linear regression analysis was performed between soc and leaf area index (lai) measured in the field (laifield) and derived by satellite (laisatellite) as well as soc and pasture reflectance in six spectra from 450 nm - 2350 nm, using the enhanced thematic mapper (etm+) sensor of satellite landsat 7. a high correlation between soc and laifield (r2 = 0.9804) and laisatellite (r2 = 0.9812) was verified. the suitability of satellite derived lai for soc determination leads to the assumption, that orbital remote sensing is a very promising soc estimation technique from regional to global scale.
On the number of slim, semimodular lattices
Gábor Czédli,Tamás Dékány,László Ozsvárt,Nóra Szakács,Balázs Udvari
Mathematics , 2012,
Abstract: A lattice L is slim if it is finite and the set of its join-irreducible elements contains no three-element antichain. Slim, semimodular lattices were previously characterized by G. Cz\'edli and E.T. Schmidt as the duals of the lattices consisting of the intersections of the members of two composition series in a group. Our main result determines the number of (isomorphism classes of) these lattices of a given size in a recursive way. The corresponding planar diagrams, up to similarity, are also enumerated. We prove that the number of diagrams of slim, distributive lattices of a given length b is the n-th Catalan number. Besides lattice theory, the paper includes some combinatorial arguments on permutations and their inversions.
REVIEWS
ATTILA J. KOVáCS,ALEXANDRU MANOLIU,TATIANA EUGENIA SESAN
Journal of Plant Development , 2009,
Abstract:
Expression Levels of the ABCG2 Multidrug Transporter in Human Erythrocytes Correspond to Pharmacologically Relevant Genetic Variations
Ildikó Kasza, Gy?rgy Várady, Hajnalka Andrikovics, Magdalena Koszarska, Attila Tordai, George L. Scheffer, Adrienn Németh, Gergely Szakács, Balázs Sarkadi
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0048423
Abstract: We have developed a rapid, simple and reliable, antibody-based flow cytometry assay for the quantitative determination of membrane proteins in human erythrocytes. Our method reveals significant differences between the expression levels of the wild-type ABCG2 protein and the heterozygous Q141K polymorphic variant. Moreover, we find that nonsense mutations on one allele result in a 50% reduction in the erythrocyte expression of this protein. Since ABCG2 polymorphisms are known to modify essential pharmacokinetic parameters, uric acid metabolism and cancer drug resistance, a direct determination of the erythrocyte membrane ABCG2 protein expression may provide valuable information for assessing these conditions or for devising drug treatments. Our findings suggest that erythrocyte membrane protein levels may reflect genotype-dependent tissue expression patterns. Extension of this methodology to other disease-related or pharmacologically important membrane proteins may yield new protein biomarkers for personalized diagnostics.
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