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Search Results: 1 - 10 of 144922 matches for " Gy?rgy Bártfai "
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Celiac disease as potential obstacle to childbearing  [PDF]
Mónika Kovács, Mária Szenes, Tihamér Horváth, Gyrgy Vajda, Beáta Gasztonyi, Gyrgy Bártfai
Open Journal of Obstetrics and Gynecology (OJOG) , 2014, DOI: 10.4236/ojog.2014.42014

AIM: The authors have aimed at confirming or excluding gluten sensitivity in infertile couples. PATIENTS AND METHODS: Between 2004 and 2010, at our outpatient clinics of immunology, both partners of 223 couples, who had striven for having a child unsuccessfully, underwent history taking, physical examination, laboratory and immuno-serologic tests including anti-tissue-transglutaminase antibody (antitTG), as well as deep duodenal biopsy in antibody-carrying patients. RESULTS: Antibodies against tissue transglutaminase were positive in 6/223 female patients of whom the diagnosis of celiac disease was histologically confirmed in 3/223 cases (1.34%). Of the male patients 2/223 (0.9%) have proven to be carriers of the antibody; histology was pathognomonic in both of them. Curiously, one of the male patients with celiac disease has been the partner of a woman who also had celiac disease diagnosed by the authors. In the followup period, a female patient and the female member of the couple with celiac disease gave birth to healthy newborns after spontaneous conception, as the result of a strictly kept gluten-free diet, as well as occasional treatments of acetylsalicylate for antiphos-pholipid syndrome or levothyroxine for latent hypothyroidism due to autoimmune thyroiditis. CONCLUSION: The results underline that it is worth performing a screening for celiac disease in both partners of couples assessed due to the lack of success in having a child, as infertility can be ceased by an appropriate diet.

The Kabachnik–Fields Reaction: Mechanism and Synthetic Use
Gyrgy Keglevich,Erika Bálint
Molecules , 2012, DOI: 10.3390/molecules171112821
Abstract: The Kabachnik–Fields (phospha-Mannich) reaction involving the condensation of primary or secondary amines, oxo compounds (aldehydes and ketones) and >P(O)H species, especially dialkyl phosphites, represents a good choice for the synthesis of α-aminophosphonates that are of significant importance due to their biological activity. In general, these three-component reactions may take place via an imine or an α-hydroxy-phosphonate intermediate. The monitoring of a few Kabachnik–Fields reactions by in situ Fourier transform IR spectroscopy has indicated the involvement of the imine intermediate that was also justified by theoretical calculations. The Kabachnik–Fields reaction was extended to >P(O)H species, comprising cyclic phosphites, acyclic and cyclic H-phosphinates, as well as secondary phosphine oxides. On the other hand, heterocyclic amines were also used to prepare new α-amino phosphonic, phosphinic and phosphine oxide derivatives. In most cases, the synthesis under solvent-free microwave (MW) conditions is the method of choice. It was proved that, in the cases studied by us, there was no need for the use of any catalyst. Moreover, it can be said that sophisticated and environmentally unfriendly catalysts suggested are completely unnecessary under MW conditions. Finally, the double Kabachnik–Fields reaction has made available bis(phosphonomethyl)amines, bis(phosphinoxidomethyl)amines and related species. The bis(phosphinoxidomethyl)amines serve as precursors for bisphosphines that furnish ring platinum complexes on reaction with dichlorodibenzonitriloplatinum.
Assessment of the Completeness of Mineral Exploration by the Application of Fuzzy Arithmetic and Prior Information
Gyrgy Bárdossy,János Fodor
Acta Polytechnica Hungarica , 2005,
Abstract: The completeness of an exploration project is of crutial importance for makingdecision to start or to give up a mining investment, or to continue the exploration to getcomplementary information. The authors discuss this problem on the example of theHalimba bauxite deposit, Hungary. Resource calculations were carried out in 12subsequent stages by fuzzy arithmetic with the aim to quantify the uncertainties of oretonnage and grade. Prior information and prior probabilities were applied to complete theexploration data. Ranges of influence for the main variables were calculated byvariograms. Spatial variability and spatial continuity of the ore bodies weremathematically evaluated. The authors found that the main geological, mining andeconomic factors must be evaluated separately and ranked according to their importance.
Construction of the hunveyor and husar experimental university space probe models, a lander and a rover in the Hungarian universities
Bérczi Szaniszló,Hegyi Sándor,Hudoba Gyrgy
Technológia vzdelávania , 2011,
Abstract: In cooperation between Hungarian universities we began constructing experimental university planetary space probe robot models in order to develop both electronics and informatics, and planetary-science/space-science education. Two forms of robot models were prepared: fix standing type landers, named Hunveyor (Hungarian UNiversity SURVEYOR) and moving robotic rovers, named Husar (Hungarian University Surface Analyser Rover) at E tv s University, Budapest, Pécs University, Pécs, and óbuda University, Alba Regia Center, Székesfehérvár. We report some basic instrumentations: a) minimal space probe energetics and electronic system, b) some basic instrumental assemblage (spectrometer, thermometer, Nürnbergian scissor type arm and the cameras), c) rover units, c) test-fields and testing experiments for soil strength analysis.
Category Theoretic Properties of the A. Rényi and C. Tsallis Entropies  [PDF]
Gyrgy Steinbrecher, Alberto Sonnino, Giorgio Sonnino
Journal of Modern Physics (JMP) , 2016, DOI: 10.4236/jmp.2016.72025
Abstract: The problem of embedding the Tsallis, Rényi and generalized Rényi entropies in the framework of category theory and their axiomatic foundation is studied. To this end, we construct a special category MES related to measured spaces. We prove that both of the Rényi and Tsallis entropies can be imbedded in the formalism of category theory by proving that the same basic partition functional that appears in their definitions, as well as in the associated Lebesgue space norms, has good algebraic compatibility properties. We prove that this functional is both additive and multiplicative with respect to the direct product and the disjoint sum (the coproduct) in the category MES, so it is a natural candidate for the measure of information or uncertainty. We prove that the category MES can be extended to monoidal category, both with respect to the direct product as well as to the coproduct. The basic axioms of the original Rényi entropy theory are generalized and reformulated in the framework of category MES and we prove that these axioms foresee the existence of an universal exponent having the same values for all the objects of the category MES. In addition, this universal exponent is the parameter, which appears in the definition of the Tsallis and Rényi entropies. It is proved that in a similar manner, the partition functional that appears in the definition of the Generalized Rényi entropy is a multiplicative functional with respect to direct product and additive with respect to the disjoint sum, but its symmetry group is reduced compared to the case of classical Rényi entropy.
Failure Mechanism of O-Ring Seals under Extreme Operating Conditions  [PDF]
Gyrgy Szabó, Károly Váradi
Modern Mechanical Engineering (MME) , 2018, DOI: 10.4236/mme.2018.81002
Abstract: In this paper the behavior of an O-ring made of NBR rubber was investigated under extreme conditions. The effect of the extreme initial compression, operating pressure and extreme temperature conditions were examined. The rubber material was tested in simple tension, pure shear and equibiaxial tension modes complemented with a Dynamic Mechanical Thermal Analysis (DMTA) to capture the viscoelastic behavior of the material. For the investigation, a large-strain viscoelastic material model was developed by the authors, to take into account the large deformations caused by extreme conditions. Insufficient space during installation causes extreme initial compression consequently leading the material to crack on the contacting outer surfaces. It was found that the excessive strain and friction induced shear stress contributes primarily to this phenomenon. Extreme operating pressure causes the seal to penetrate into the gap between the shaft and the housing. This behavior damages the material and cracks appear on the seal. High strain areas were found in the proximity of the gap in the material. The analysis of the extreme operating temperature showed that during cooling the O-ring can completely loose its ability to seal at -70°C. There are three contributing factors: the speed of cooling, the temperature and the coefficient of thermal expansion.
Thermal-Mechanical Coupled FE Analysis for Rotary Shaft Seals  [PDF]
Gyrgy Szabó, Károly Váradi
Modern Mechanical Engineering (MME) , 2018, DOI: 10.4236/mme.2018.81007
Abstract: The aim of this paper is to model the steady-state condition of a rotary shaft seal (RSS) system. For this, an iterative thermal-mechanical algorithm was developed based on incremental finite element analyzes. The behavior of the seal’s rubber material was taken into account by a large-strain viscoelastic, so called generalized Maxwell model, based on Dynamic Mechanical Thermal Analyses (DMTA) and tensile measurements. The pre-loaded garter spring was modelled with a bilinear material model and the shaft was assumed to be linear elastic. The density, coefficient of thermal expansion and the thermal conductance of the materials were taken into consideration during simulation. The friction between the rotary shaft seal and the shaft was simplified and modelled as a constant parameter. The iterative algorithm was evaluated at two different times, right after assembly and 1 h after assembly, so that rubber material’s stress relaxation effects are also incorporated. The results show good correlation with the literature data, which state that the permissible temperature for NBR70 (nitrile butadiene rubber) material contacting with ~80 mm shaft diameter, rotating at 2600/min is 100°C. The results show 107°C and 104°C for the two iterations. The effect of friction induced temperature, changes the width of the contact area between the seal and the shaft, and significantly reduces the contact pressure.
Imre Kádár,Gyrgy Béndek,József Koncz
Poljoprivreda (Osijek) , 2000,
Abstract: Four levels of N, P and K nutrition (poor, moderate, satisfactory and high) and all their possible combinations with 64 treatments in two replications (128 plots) were studied in a long term field trial on barley yield and malting quality. A standard East-European spring barley "Opal" (bred in Czechoslovakia) was grown in 1986, 13th year of the agricultural experiment, involving various crops in previous years, on a calcareous loamy chernozem soil. The optimum fertility levels for yield enhancement resulted in the poorest malting quality: low modification and extract but long saccharification time and high protein. To solve this problem the brewing industry will have to apply the well-known technological methods available since growers are not likely to give up their fertilizers. Applying soil and plant analysis data, having knowledge about both soil and plant optimum values, the danger of the excessive use of fertilizers can be realized and decreased.
Gyrgy Bázár,Zoltán Princz,Gabriella Jekke,László Locsmándi
Poljoprivreda (Osijek) , 2007,
Abstract: The goal of this study was to develop calibration equations to predict the chemical composition of raw,homogenized rabbit meat by means of near infrared spectroscopy (NIRS). 44 Pannon White rabbits were housedin groups in three different pen types (16 anim./m2), and were fed the same diet. Another 45 animals were housedin cages (12 anim./m2) and fed by different feeding regimes. Rabbits were slaughtered at the bodyweight of 2.4-2.5kg. Homogenized fresh and freeze-dried left total hind leg muscles were investigated by NIRS using a NIRSystem 6500 equipment with small ring cup sample holder. The ether extract and protein content of all samples were determined chemically. Samples 44 of housing experiment were applied in producing LOCAL calibration equations tested on the 45 samples from the separate feeding experiment. Coefficients of determination (R2) of the predictions were 0.89 and 0.99 for fat, 0.85 and 0.96 for protein in fresh and freeze-dried samples, respectively. Results are reassuring, because the equations were applicable, however the analyzed samples were from independent housing and feeding systems. Therefore the chemical compositions differed in the two datasets, i.e. 9.46%, and 11.79% for fat, 85.75% and 83.44% for protein content in calibration and prediction datasets, respectively. The average of NIRS predicted values for fat and protein was 11.36%, 83.88% or 11.54%, 83.45%when using fresh or freeze-dried samples, respectively.
Backcasting for Sustainable Employment: A Hungarian Experience
Alexandra K?ves,Gábor Király,Gyrgy Pataki,Bálint Balázs
Sustainability , 2013, DOI: 10.3390/su5072991
Abstract: Sustainability and employment are terms seldom used together. Especially when defining sustainability in the stricter sense of the word, delineating a world where strong sustainability is the norm, it is problematic to deduct which elements may compose sustainable employment. In the relevant discourse, two distinct directions can be identified. Ecological modernization promises “quick fixes” to employment problems while reducing environmentally harmful economic activities without initiating major changes either in our ways of thinking or in our way of living. At the same time, the radical change paradigm disposes of the concepts of the free market society and believes that new “great transformations” are unavoidable, whereby values must change just as much as institutions. Yet, how far have these normative theoretical approaches penetrated our everyday thinking? The paper builds upon the experience of a backcasting project on sustainable employment conducted in Hungary in 2012 and early 2013 and suggests that when people are given the chance to leave the path dependencies of today behind and imagine a sustainable future, their normative visions provide us with invaluable insight as to what may constitute sustainable employment. It also contributes towards our understanding of which policy tools lead us towards a more sustainable world of work in particular and a more sustainable society in general.
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