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  • Author or Editor: Balázs Kovács x
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Authors: Balázs Muraközy and Tamás Kovács
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Authors: Balázs Borsi and György Kovács
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Understanding and simulating the interaction of groundwater and surface water is essential to hydrologists. Water supply and water quality aspects are a few examples of common water-resource issues where understanding the interconnections of groundwater and surface water is fundamental to develop an effective water-resource management and policy. In our study a detailed investigation of a riverbank aquifer was performed to be able to simulate and predict the behavior of the flow system. The continuous hydraulic head measurements in the area of interest showed strong influence on the hydraulic head field caused by intensively changing river head at a distance from the river up to 3,500 m. Based on the results steady state and transient flow calculations were compared, and a great effort has been made to ensure that the model more precisely describe the time and space variable flow field. Beside fulfilling the standard calibration requirements, a multi-step calibration process was performed.

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Bolygónk lakosságának 2–3%-át érinti a hepatitis C-vírus-fertőzés, amely a fertőzöttek több mint felénél krónikus májgyulladást okoz, és a májzsugorodás, a májelégtelenség, a májsejtrák, az ezek miatt szükségessé váló májátültetés, valamint a májeredetű halálozás egyik leggyakoribb oka. A XXI. század első évtizedében arany standarddá vált pegilált interferon-alfa és ribavirin kettős kezeléssel a hazánkban domináló G1 genotípussal fertőzött, korábban még nem kezelt betegek ~40%-a ér el tartós vírusmentességet, a korábban sikertelenül kezelt betegek ismételt kezelésekor pedig csak minden ötödik. A közelmúltban törzskönyvezett két új, hepatitis C-vírus elleni proteázgátló, direkt antivirális hatású készítmény (boceprevir és telaprevir) hozzáadásával a korábban még nem kezelt betegek csaknem háromnegyede, a korábban sikertelenül kezelt betegeknek pedig több mint fele számíthat gyógyulásra. A terápia sikerét jelentősen korlátozza, hogy a gyakori – és esetenként súlyos – mellékhatások miatt a gyógyszereket a betegek egyharmada az optimálisnál alacsonyabb dózisban és/vagy rövidebb ideig kaphatja. További kihívást jelent, hogy a kettős kezelés során alkalmazott készítmények mellékhatásait az új készítmények fokozhatják (különösen anaemia), másrészt új mellékhatások is jelentkezhetnek (például boceprevir esetén ízérzészavar, telaprevir esetén bőrkiütések). Az összefoglaló célja a terápiához kapcsolódó mellékhatások és ezek kezelésének áttekintése a készítmények alkalmazási előírásai, az ezek alapját képező közlemények és a készítményeket használó szakemberek tapasztalatai alapján – abban a reményben, hogy ez segítséget nyújthat a kezelést végző kollégáknak a standard és az új készítmények biztonságos és hatékony alkalmazásához. Orv. Hetil., 2011, 152, 1997–2009.

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With the intent of making data acquisition for fractal geometry-based discrete fracture network (DFN) modeling time-efficient and automatized, a new method was established. For the automation of data retrieval from the images of the studied surfaces, a series of image-processing operations and MATLAB algorithms have been developed. The method allows the retrieval of more than 1,000 fracture-length data/cm2 of one sample in several minutes. This methodology tends to be a useful tool in studies of fracture network geometries. DFN models of a supposed excavated and/or environmental damage zone, designed with the use of data supplied by the above method, are presented in this work as an example.

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The geologic, geotechnical and rock mechanical background of the area, which includes an underground cavern system, is very complex. Initially, to describe the rock mass properties, the RMR and Q systems were used, while the rock support system was based solely on the Q system. Later, during construction of the repository chambers, the GSI system was also introduced in addition to the above-mentioned rock classification methods. The correlation and usage of these three different rock mass classification systems were investigated.Special methods were used to obtain more accurate tunnel mapping and documentation, which is based on photogrammetry and photo analyzer software.According to the results, the correlation between the RMR and Q values is independent of the rock type; basically, the same equation can be used for all (differences between experimental error). The GSI intervals also closely follows the same trend as the results of the other two methods.

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Authors: Balázs Vásárhelyi, László Kovács and Ágnes Váró

Abstract

Fissuring of rocks is frequently of greater importance in practical rock engineering operations than the strength of the intact rock. In practice boreholes are usually analyzed by the RQD method. The limitation of this method has been discussed by several authors: for example, for RQD = 0 % [that is, where the joint intercept (distance between joints in the cores) is 10 cm or less], or RQD = 100%, the RQD provides no information on the core pieces themselves. It does not matter whether the discarded pieces are soil or fresh rock pieces up to 10 cm in length. In early 2003, more than 3,000 meter-long boreholes were analyzed in parallel with two different methods: traditional RQD, and Hansági's C (or Kiruna) Method. According to the results, in the case of a very good or very poor core, the C method shows the jointing patterns better than the widely-used RQD method. The goal of this paper is to present the C method and its advandages/disadvandages. Linear regression was found for the values between 10% < RQD < 90%, but the C value is much more sensitive than the RQD. The classification of the boreholes according to C method is also presented.

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Particle size distribution (PSD) is one of the most important fundamental physical properties of soils, as it determines their physical, chemical, mechanical, geotechnical, moreover environmental behaviour. Although the measurement of PSD with different techniques is commonly performed in soil laboratories, their automation and continuous PSD curve generation have not been solved yet.  However, there are some physical principles, various sensors and different data storing methods for measuring the density-time function. In the present paper a possible solution is introduced for the measurement of the soil particle density database as a function of settling time. The equipment used for this purpose is an areometer that is widely used e.g. for determining the sugar content of must, or the alcohol content of distilled spirits, etc. The device is equipped with patent pending capacitive sensors on the neck of the areometer. It measures the changes in the water levels nearby the neck of the areometer in 1 μm units with <10 μm accuracy. The typical water level changes are 3-5 cm, which makes possible a very accurate determination of particle density changes due to settling in particle size analysis. The measured signals are stored in the equipment's memory and can be downloaded to the controller computer via a modified USB port. Data evaluation can be carried out online or later. The large number of measured data points led to the introduction of a new evaluation method, the Method of FInite Tangents or shortly the “FIT Method”. The dispersed soil particle system is considered as the aggregation of many mono-disperse systems. From this it follows that the measured density-time function can be divided into grain size fractions with tangent lines drawn to finite, but optional points. These tangent lines are suitable for calculating the settling speed of a given fraction, as the changing speed of density is equal to the multiplication of settling speed and mass of the given grain size fraction. The settling speed of all fractions is calculable by using the Stokes law, so the mass of all of the floating fraction can be calculated. Because the soil suspension is a poly-disperse system, the measured density decrease can be considered as an integration of finite mono-disperse systems. From this, it follows that it can be interpreted as the sum of linear density vs. time functions. If the mass of each grain size fraction is known, the particle size distribution is calculable. The method is relatively easily programmed and the intervals of grain size fractions are freely adjustable, so with this program almost all types of particle size distribution are calculable, not only those being uniform. Using the appropriate controller and evaluation program, soil particle size distribution can be calculated immediately after downloading the measured data. This technique does not need more sample preparation than past methods. The automated reading lessens the manpower required for performing the measurement - which also reduces human error sources - and provides very detailed PSD data that has advantages, among others, like revealing multi-modality in the particle-size distribution.

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Authors: Balázs Bende, Krisztina Borbála Kovács, Norbert Solymosi and Tibor Németh

The objective of this study was to describe the epidemiology of canine urolithiasis in Hungary in order to determine the annual incidence of urolithiasis and to identify breeds at risk for different types of urolithiasis. Data of a total of 2,543 canine uroliths analysed in the laboratory of the Budapest Urolith Centre were evaluated retrospectively from 2001 to 2012. Logistic regression was used to assess odds ratios for the proportion of each affected breed compared to those of crossbreeds. The annual incidence of urolithiasis was evaluated by the number of submissions compared to the estimated number of dogs in the population from which the samples originated. Epidemiologic data revealed a relatively high and increasing proportion of struvite urolithiasis. Statistical analysis of breed predispositions resulted in the detection of breeds not having been reported at risk (e.g. Bernese Mountain dog — struvite, Bichon Frise, Bolognese, Tibetan Terrier — purine, French Bulldog — cystine). Conflicting results were revealed for some other breeds previously described as being affected by certain types of urolithiasis (Chihuahua, Pekingese, Shih Tzu, English Cocker Spaniel). Regardless of the type of urolithiasis, its average cumulative incidence in the dog population of Hungary was found to be 1.76/10,000/year.

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