Clumped isotope paleotemperatures from MIS 5 soil carbonates in southern Hungary

Quantitative paleotemperature reconstructions for the continents, including East Central Europe, over marine isotope stage 5 (MIS 5) and specifically the last interglacial (LIG, MIS 5e) are scarce and mostly based on pollen assemblages. Here we provide soil and air temperature reconstructions for the summer season of MIS 5e (5c) using carbonate clumped isotope thermometry applied to soil carbonate concretions in the Dunaszekcső loess-paleosol record, Southern Hungary. The sediments making up the S1 pedocomplex investigated represent the MIS 5 as demonstrated by bracketing K-feldspar post-IR-IRSL225/290 ages of ~63 to 164 ka. Both the absolute ages and pedogenic susceptibility (χP) curve indicate that all the subtages of MIS 5 were found to be recorded in the sequence, and soil carbonates found >1 m depth below the paleosurface of the S1 soil provide pristine, undisturbed isotopic signals. The soil carbonate concretions likely formed during MIS 5e at a relatively shallow (20–50 cm) depth, but a later formation during MIS 5c at >50 cm depth is also plausible. Clumped isotope-based soil temperatures (ST-Δ47sc) ranged from 16 to 20 °C, and reconstructed summer season air temperatures (SATs) for the LIG are consistently lower than the modern values at the site by ~1–5 °C, matching surprisingly well the soil bacteria membrane lipid-based MIS 5e air temperature estimates from a nearby Serbian site. At the same time, the reconstructed SAT values do not match the 2–4 °C positive warm season anomalies modeled for East Central Europe between LIG and present-day in paleoclimate simulations. ST uncertainties of 1–6 °C, infiltration-driven cooling of soil temperatures, and the possibility of MIS 5c formation of the investigated carbonates may account for this proxy-model data discrepancy. Oxygen isotope compositions of summer season paleo-rainwaters for MIS 5e (5c), as reconstructed using the ST-Δ47sc and δ18Osc data of soil carbonates, were found in a range of −6.7 and −6.4‰, matching the modern mean summer season value of −6.2 ± 0.94‰ within error

Particle physics education in Hungary

AbstractIn recent years various educational activities have been pursued in Hungary with the aim to raise the interest of high school students in natural sciences, and especially in physics. This brief summary will present some of the key projects of broader interest for the scientific community

A preliminary chronological study to understand the construction phases of a Late Copper–Early Bronze Age kurgan (kunhalom)

The aim of this study is to identify the milestones of landscape evolution around the Ecse Mound (Karcag-Kunmadaras, Hortobágy National Park, Hungary) in the Holocene period by sedimentological and malacological analysis of strata underneath and within the body of the kurgan concerned, including that of the same characteristics of the artificially piled layers. An undisturbed core drilling was carried out and the sedimentological properties of both the mound and of the substrate baserock were revealed, analysis of which has been supported by three radiocarbon (AMS) measurements. The baserock formation during the last phase of the Ice Age, Middle and Upper Pleniglacial, and Late Glacial phases was followed by soil development in the Holocene, while the mound was constructed in two phases at the end of the Copper Age by the communities of the Pit Grave (Yamna or Ochre Grave) Culture. By publishing these preliminary data, it is also intended to draw attention to the need of focused research efforts by standardized methodology in kurgan research, in order to make the results of different studies consistent and comparable

Indicators and Methods to Understand Past Environments from ExoMars Rover Drills

Great advances are expected during the analysis of drilled material acquired from 2 m depth by ExoMars rover, supported by the comparison to local context, and the joint use of different instruments. Textural information might be less detailed relatively to what is usually obtained at outcrops during classical geological field work on the Earth, partly because of the lack of optical imaging of the borehole wall and also because the collected samples are crushed. However sub-mm scale layering and some other sedimentary features might be identified in the borehole wall observations, or in the collected sample prior to crushing, and also at nearby outcrops. The candidate landing sites provide different targets and focus for research: Oxia Planum requires analysis of phyllosilicates and OH content, at Mawrth Vallis the layering of various phyllosilicates and the role of shallow-subsurface leaching should be emphasized. At Aram Dorsum the particle size and fluvial sedimentary features will be interesting. Hydrated perchlorates and sulphates are ideal targets possibly at every landing sites because of OH retention, especially if they are mixed with smectites, thus could point to even ancient wet periods. Extensive use of information from the infrared wall scanning will be complemented for geological context by orbital and rover imaging of nearby outcrops. Information from the context is especially useful to infer the possible action of past H2O. Separation of the ice and liquid water effects will be supported by cation abundance and sedimentary context. Shape of grains also helps here, and composition of transported grains points to the weathering potential of the environment in general. The work on Mars during the drilling and sample analysis will provide brand new experience and knowledge for future missions

Magnetic susceptibility in the European Loess Belt: New and existing models of magnetic enhancement in loess

Magnetic susceptibility measurements play a key role in Quaternary studies. Magnetic proxies, such as low field and frequency-dependent magnetic susceptibility, are widely applied in the reconstruction of terrestrial paleoclimate, e.g., in the study of loess-paleosol successions. In general, the interpretation of loess magnetic susceptibility signals is based on two commonly accepted models: the pedogenic magnetic enhancement and wind-vigour models. However, there are an increasing number of cases where such models cannot be used. These cases show unusual relationships between the two common loess magnetic susceptibility proxies: low field and frequency-dependent magnetic susceptibility. Such relationships have been attributed to various phenomena including the dissolution of fine-grain minerals and the formation of ultrafine magnetic rims on the surface of coarser grains by weathering. Despite the growing number of these exceptional cases of magnetic enhancement, our knowledge about the occurrence and potential causes of the unusual behaviour of magnetic susceptibility parameters is still limited. This, in turn, hinders the wider application of magnetic susceptibility parameters in loess. To fill this knowledge gap, magnetic susceptibility data of various profiles from the European Loess Belt were collected and compared to reveal various enhancement trends in loess. Along with the analysis of magnetic susceptibility parameters, combined scanning electron microscopy (SEM) and rock magnetic analyses were applied to samples from the Paks loess sequence in Hungary to describe some of the irregular cases, notably the cause of increasing frequency-dependent susceptibility in non-altered sediments. Analysis of loess, paleosol and common mineral samples separated from loess (e.g., muscovite) revealed that various features may be responsible for these increasing frequency-dependent susceptibility values: i) surface weathering (maghemitization) of coarser detrital grains, ii) nanofragmentation by physical weathering and iii) the appearance of significant amounts of ultrafine magnetic inclusions in micas. These special modes of magnetic enhancement of loess do not undermine the importance of the basic theories suggested above, but rather provide three mechanisms that account for some of the increasing number of unusual cases. To aid in the wider and more accurate use of magnetic susceptibility parameters in loess, we review the current magnetic enhancement models with special emphasis on the identification of unusual trends in magnetic enhancement and understanding their drivers.Project BU235P18 (Junta de Castilla y Leon, Spain) and the European Regional Development Fund (ERD), project PID2019-108753GB-C21/AECI/ 10.13039/501100011033 of the Agencia Estatal de Investigación and project PID2019-105796GB-100/AECI/ 10.13039/501100011033 of the Agencia Estatal de Investigación. Part of the measurements were conducted during a fellowship awarded to B. Bradák at Kobe University, Japan, by the Japan Society for the Promotion of Science (JSPS; P15328). Part of this study was conducted within the cooperative research programme of the Center for Advanced Marine Core Research, Kochi University (15A001, 16A002, 17A016), with the support of the Japan Agency for Marine-Earth Science and Technology (JAMSTEC). The Swedish Research Council is gratefully acknowledged for funding to TS for part of this project (2017-03888)

Magnetic fabric of loess and its significance in Pleistocene environment reconstructions

A summary of approximately three decades and greater than thirty loess magnetic fabric studies is presented here. The revised studies cover various loess regions from the Chinese Loess Plateau across the European Loess Belt to Alaska. Although there is still an ongoing argument about the feasibility of the magnetic fabric of loess in paleowind reconstructions, the determination of prevailing wind direction during various periods of the Pleistocene is the main goal of magnetic anisotropy analysis of the revised loess successions. The magnetic fabric analysis of loess from Chinese Loess Plateau provided significant information about the characteristics of paleomonsoon in East Asia, and the results from other loess regions, such as Alaska, the European Loess Belt, and Siberia, are also promising. As it is shown in this review, the synthesis of the paleowind direction results from the studied profiles may already provide a significant foundation for future climate models by the reconstruction of key climate centres and main continental level wind tracks. Besides the reconstruction of prevailing paleowind directions, there are numerous loess magnetic fabric studies using magnetic anisotropy parameters in the reconstruction of the characteristics of long-term climate trends, climate transitions and glacial- interglacial cycles. There are some lesser known aspects contributing to magnetic fabric of loess, such as the influence of various types of magnetic contributors on the overall fabric (i.e. the study of sub-fabrics) and their role in environment reconstruction. Besides the identification of aeolian magnetic fabric, not so many studies focus on the magnetic anisotropy characteristics of materials, possibly developed by water-lain sedimentation, pedogenesis, mass movements and permafrost activity. Novel results from Hungarian loess, especially from Paks, connected to some of the latter topics are also presented. Such topics includes the analysis of the nanofabric in paleosols, developed by pedogenesis, the comparison of magnetic fabric, formed during high energy transportation by aeolian or aquatic agents, and the periodicity analysis of magnetic parameters during the early Middle Pleistocene. New research lines, introduced in this review, may inspire new researches, and provide new perspectives for the next generation of magnetic anisotropy studies of loess successions.Project BU235P18 (Junta de Castilla y Leon, Spain) and the European Regional Development Fund (ERD), project PID2019-108753GB-C21/AECI/10.13039/501100011033 of the Agencia Estatal de Investigación and project PID2019-105796GB-100/AECI/10.13039/501100011033 of the Agencia Estatal de Investigación. A fellowship was awarded to B. Bradák at Kobe University, Japan, by the Japan Society for the Promotion of Science (JSPS; P15328) during the period of 2015.10–2017.10

Predictors of maternal and neonatal morbidity and early neonatal mortality in Robson-classified deliveries over 10 years in a tertiary care obstetric unit of Hungary

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A császármetszés frekvenciájának Robson-féle klasszifikáció szerinti elemzése a Debreceni Egyetem Szülészeti és Nőgyógyászati Klinika tízéves anyagában

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