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  • Author: László Márton x
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Strike-slip reactivation of a Paleogene to Miocene fold and thrust belt along the central part of the Mid-Hungarian Shear Zone

Strike-slip reactivation of a Paleogene to Miocene fold and thrust belt along the central part of the Mid-Hungarian Shear Zone

Recently shot 3D seismic data allowed for a detailed interpretation, aimed at the tectonic evolution of the central part of the Mid-Hungarian Shear Zone (MHZ). The MHZ acted as a NW vergent fold and thrust belt in the Late Oligocene. The intensity of shortening increased westwards, causing clockwise rotation of the western regions, relatively to the mildly deformed eastern areas. Blind thrusting and related folding in the MHZ continued in the Early Miocene. Thrusting and gentle folding in the MHZ partly continued in the earliest Pannonian, and was followed by sinistral movements in the whole MHZ, with maximal displacement along the Tóalmás zone. Late Pannonian inversion activated thrusts and generated transpressional movements along the Tóalmás zone.

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Investigation And Design Of Durable Pavement Structure Rehabililation

Abstract

Preservation of the appropriate quality of road assets needs timely rehabilitation of high-level design and construction. Since the actual life cycles of Hungarian road rehabilitation projects are often much lower than expected, research activities of the authors were concentrated on the development of an updated design technology of road pavement rehabilitation using scientifically based algorithms. The paper outlines the elements of a pavement rehabilitation design based on Hungarian and foreign literature survey, detailed own laboratory test series and trial section monitoring. The main steps of the design methodology comprise the Client’s data supply and disposition, site condition evaluation by the designer, deflection measurement in carefully selected points, eventual additional laboratory tests, choosing design subsections, correction of the equivalent thickness of the new asphalt layer, calculation of strain in wearing course. Besides, relationships are presented between various condition parameter data like bearing capacity values, unevenness measuring data and rut depth values. The pavement rehabilitation design technique suggested here – if widely in Hungary – can significantly contribute to attaining a much longer life cycle of rehabilitated roads than by now, and it is (would be) extremely efficient due to the very limited funds available for highway purposes.

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A new Middle Miocene selachian assemblage (Chondrichthyes, Elasmobranchii) from the Central Paratethys (Nyirád, Hungary): implications for temporal turnover and biogeography

Abstract

A new Middle Miocene (Langhian - early Serravallian) assemblage with shark and ray teeth from Nyirád (Hungary, Transdanubia, Veszprém County) consists of nine families, with 15 different species. The assemblage shares many common genera with other Middle Miocene assemblages in the Paratethys (Notorynchus, Carcharias, Otodus, Cosmopolitodus, Hemipristis, Galeocerdo, Carcharhinus, and Aetobatus), and reflects a subtropical climate and a close connection with the Mediterranean Sea. However, a detailed faunal compilation of Miocene selachians reveals that several taxa that were still present in the Mediterranean or lived in the Paratethys during the Lower Miocene disappeared or became very rare by the Middle Miocene in the Central Paratethys (e.g., Isistius, Centrophorus, Mitsukurina, Carcharoides, Parotodus, Alopias). The taxa that went locally extinct in the Paratethys are mainly represented by deep-water or pelagic forms. Their disappearance is most probably related to the gradual separation of the Paratethys from the Mediterranean. The common presence of some large, rather pelagic sharks (e.g., Otodus, Cosmopolitodus) in the Central Paratethys during the Middle Miocene is explained here by the widespread occurrence of their potential prey represented by marine mammals (e.g., whales and dolphins).

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Review. Automatic Segmentation Techniques of the Coronary Artery Using CT Images in Acute Coronary Syndromes

Abstract

Coronary artery disease represents one of the leading reasons of death worldwide, and acute coronary syndromes are their most devastating consequences. It is extremely important to identify the patients at risk for developing an acute myocardial infarction, and this goal can be achieved using noninvasive imaging techniques. Coronary computed tomography angiography (CCTA) is currently one of the most reliable methods used for assessing the coronary arteries; however, its use in emergency settings is sometimes limited due to time constraints. This paper presents the main characteristics of plaque vulnerability, the role of CCTA in the assessment of vulnerable plaques, and automatic segmentation techniques of the coronary artery tree based on CT angiography images. A detailed inventory of existing methods is given, representing the state-of-the-art of computational methods applied in vascular system segmentation, focusing on the current applications in acute coronary syndromes.

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Issues of The Usability of Copper Ore (Chalcopyrite) From Bălan for Ustensiles Production in The Bronze Age

Abstract

Archaeological publications connect the raw material used for the production of copper and bronze artifacts discovered during the excavations carried on in Szeklerland to the use of the chalcopyrite from the Bălan copper ore deposit. So far, this assumption has not been confirmed by concrete evidence. Men of the Bronze Age can’t possibly have had knowledge of the metallurgy of sulphide-type copper ores such as chalcopyrite. Applying investigations based on spectroscopy, the Bronze Age use of chalcopyrite from Bălan could be either confirmed or refuted, the new data throwing more light on the provenance of the bronze artifacts discovered in the Szeklerland.

Open access
Temporal changes in the diet composition of the Eastern Imperial Eagle (Aquila heliaca) in Hungary

Abstract

The diet composition of breeding Eastern Imperial Eagles (Aquila heliaca) was analysed in Hungary between 2005 and 2017, and compared with two previously published datasets from the periods of 1982–1991 and 1992–2004. Altogether the distribution of 8543 prey items of 126 different species and 29 other taxa were analysed within a 36-years period. We found that the previously abundant Common Hamster (Cricetus cricetus) became marginal (7.42%), while European Sousliks (Spermophilus citellus) practically disappeared (0.03%) from the diet of Imperial Eagles. Small game species, like the Common Pheasant (Phasianus colchicus) and the Brown Hare (Lepus europaeus) composed a remarkable part of the diet (11.22% and 28.11% respectively), which raised some conflicts with hunters regionally and probably also contributed to the high prevalence of persecution incidents against the eagles. In parallel with the loss of traditional prey species, corvids (13.10%), pigeons (8.90%), waterbirds (6.83%), other rodents (6.71%), Roe Deers (Capreolus capreolus) (5.59%), raptors and owls (4.88%) became regularly detected prey species. The temporal changes of the main prey categories were analysed between 1998 and 2017, when the ratio of Hamster and Pheasant showed significant decrease (-27.29% and -6.38%, respectively). The ratio of Brown Hare also showed slight decrease (-3.98%), but the change was not significant. On the other hand, the ratio of corvids, waterbirds and Roe Deers within the diet showed significant increase (+18.20%, +6.25% and +5.39%, respectively). The observed flexibility in the foraging behaviour of Imperial Eagles greatly facilitate conservation efforts, as they seems to be able to utilize the most abundant prey sources, i.e. they were not depending solely from the status of any single specific prey source. However, eagles could only shift and survive in those regions, where their traditional preys decreased, if alternative species were available for them.

Open access
Sources of variation in haematocrit in the Collared Flycatcher (Ficedula albicollis)

Abstract

The haematocrit rate of the blood shows the individual physiological state. As the haematocrit grows, the higher erythrocyte number results in more efficient oxygen uptake capacity which can lead to better performance and probably a better survival rate of an individual. Hence we assume that the high value of haematocrit reflects good health state. Altogether 308 blood samples were collected from a wild population of Collared Flycatchers (Ficedula albicollis) in two breeding stages during a period of 2008-2010. We tried to elucidate the relationship between condition and haematocrit level of an individual and studied the haematocrit changes of an individual between years. The haematocrit values differed between years. Females had higher haematocrit values than males in 2010 but not in 2009. At courtship the haematocrit level of males was higher, than during nestling care. The different environmental effects and energy demands of the individuals may be the driving force behind the observed changes in haematocrit level. Analysing the changes between two years, there was a positive correlation between changes in condition index and haematocrit of individuals. The haematocrit values of an individual were repeatable between years. This finding suggests that haematocrit can be informative about the individual’s general health state.

Open access
Continuous field soil moisture content mapping by means of apparent electrical conductivity (ECa) measurement

Abstract

A soil moisture content map is important for providing information about the distribution of moisture in a given area. Moisture content directly influences agricultural yield thus it is crucial to have accurate and reliable information about moisture distribution and content in the field. Since soil is a porous medium modified generalized Archie’s equation provides the basic formula to calculate moisture content data based on measured ECa. In this study we aimed to find a more accurate and cost effective method for measuring moisture content than manual field sampling. Locations of 25 sampling points were chosen from our research field as a reference. We assumed that soil moisture content could be calculated by measuring apparent electrical conductivity (ECa) using the Veris-3100 on-the-go soil mapping tool. Statistical analysis was carried out on the 10.791 ECa raw data in order to filter the outliers. The applied statistical method was ±1.5 interquartile (IRQ) distance approach. The visualization of soil moisture distribution within the experimental field was carried out by means of ArcGIS/ArcMAP using the inverse distance weighting interpolation method. In the investigated 25 sampling points, coefficient of determination between calculated volumetric moisture content data and measured ECa was R2 = 0.87. According to our results, volumetric moisture content can be mapped by applying ECa measurements in these particular soil types.

Open access