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We report here for the first time the composition and mineralogical studies on a new meteorite, which was found in August 2012 near the village of Csátalja, Hungary (46°0׳21׳׳N; 18°59׳27׳E). The Csátalja meteorite is classified as a H4–5 ordinary chondrite with shock stage S2 and a degree of weathering W1 and the total mass is 15 kg. The Csátalja meteorite is characterized by well-defined chondrules composed either of olivine or pyroxene. X-ray diffractogram shows the primary phases olivine, pyroxene, kamacite, and albite. Metal particles were extracted from the bulk powdered samples exhibit only kamacite and small amounts of the intergrowth taenite/kamacite. Raman spectra of forsterite indicate that Csátalja meteorite suffered from relatively low shock pressure regime. The texture of chondrules varies from nonporphyritic (e.g., barred olivine, radial pyroxene) to porphyritic ones (e.g., granular olivine as well as olivine pyroxene). The meteorite name has not yet approved by the Nomenclature Committee of the Meteoritical Society. [ABSTRACT FROM AUTHOR]

There is an increasing need for paleoclimate records from continental settings to better understand the climatic changes during critical periods such as the Pliocene and Early Pleistocene. Present data indicates a transition from a warmer than present-day climate to a substantially different cooler climate. This study reviews the oxygen and carbon isotope compositions of mammalian tooth enamel for the Pliocene and Early Pleistocene of South and Central Europe to reconstruct the spatial distribution and temporal changes of the vegetation and oxygen isotope composition of precipitation (δ18O ppt). In addition to a literature review, this study adds new stable isotope measurements for this period. All δ13C values indicate C 3 ecosystems and reflect major changes in the water use efficiency and/or in the prevailing humidity. The reconstructed major floral types range from woodland to woodland ‒ mesic grassland in all of the investigated regions. The carbon isotope compositions of fossil mammal teeth demonstrate that the spatial distribution of vegetation was broadly similar to those of the present-day for the Early/Late Pliocene – Early Pleistocene, with the most "closed" vegetation in Central and Northern Italy, while open mesic grassland vegetation covers can be reconstructed for the Iberian Peninsula, Massif Central region (Central France) and the Carpathian Basin. The calculated δ18O ppt values give a negative temporal shift of about 1–1.5‰ from the Early Pliocene to Late Pliocene – Early Pleistocene in three regions (Iberian Peninsula, Central Italy, Carpathian Basin), potentially representing a 1.5–3.0 °C decrease in mean annual temperatures (MAT) over time. In the Massif Central region and the Carpathian Basin, the δ18O ppt values are almost the same for the Late Pliocene and Early Pleistocene, while in Northern Italy the values decreased over that period. The δ18O ppt values are in the range of present-day δ18O ppt values over the Early Pliocene and somewhat lower than present-day values for the Late Pliocene - Early Pleistocene in most of the regions. Because most other proxies indicate warmer than present-day climate for the Early Pliocene and similar to present-day climate for the Early Pleistocene, the δ18O ppt values are generally lower than expected, which can be partially explained by local effects. • Data indicates a transition from a warmer than present-day climate to a substantially different cooler climate. • δ13C values reflect changes in the water use efficiency and/or in the prevailing humidity. • Major floral types range from woodland to woodland ‒ mesic grassland. • δ13C values and paleovegetation support a dominance of C 3 ecosystems. • δ18O ppt values are generally lower than expected, which can be partially explained by local effects. [ABSTRACT FROM AUTHOR]

Abstract: Stable carbon and oxygen isotope values (δ13C, δ18O) of structural carbonate were determined in the bioapatite component of fossil teeth from the Czech Republic, Slovakia and Hungary. Oxygen isotope compositions of enamel and dentin samples provide new quantitative records of the Late Pleistocene climate in East Central Europe (ECE). These δ18O data were combined with records of oxygen isotope values of recent and paleogroundwaters to study the spatial patterns and temporal variations in the oxygen isotope composition of precipitation and the thermal climate over ECE. The new isotopic data suggest that surface air temperatures in the study region between 33 and 12 ka were 2–9 °C colder than present. Specimens of woolly mammoth, rhino and horse from the Late Pleistocene were primarily C3 grazers. [Copyright &y& Elsevier]

Abstract: The Csajág mammoths were discovered during road construction work in June 2006. The skeletal remains are well preserved in an Upper Pleistocene loess deposit. This revealed the skeletons were an adult female woolly mammoth (Mammuthus primigenius) of estimated age 24–25 years, largely complete except for the skull; and the partial skeleton of a juvenile of age 6–7 years at death. A tooth sample has been radiocarbon dated (AMS) and is of Late Pleniglacial (MIS 2) age (16.9–15.9 ka cal BP). This new radiocarbon evidence fits into the well-known colonization pattern of M. primigenius in East Central Europe and confirms a continuous distribution at the end of the Late Pleistocene. [Copyright &y& Elsevier]

Abstract: Different aspects of the melt stabilising effect of various antioxidant packages were studied in a Phillips type polyethylene in the work described in this series of papers. The polymer was stabilised with various combinations of a phenolic antioxidant with phosphite, phosphonite, and phosphine type secondary antioxidants and processed by multiple extrusions followed by film blowing. After determining the role of the antioxidants in the melt stabilisation process and the effect of antioxidant consumption on polymer properties the correlation of the rheological characteristics of polymer with the tear and impact strengths of films is discussed in this paper. The Elmendorf tear strength of films measured in transverse direction, which is sensitive to long chain branching, correlates closely with viscous compliance determined by creep recovery experiments and the ratio of melt flow indices measured at high and low loads. The relationships are independent of the type and amount of antioxidant added. This makes possible the prediction of the effect of various antioxidant packages on film properties on the basis of rheological measurements. The correlation between the dart drop impact strength of the films and the rheological characteristics of the polymer is less reliable. [Copyright &y& Elsevier]

Abstract: Terrestrial red clays underlying Quaternary loess deposits, or filling fissures and recently existing caves in limestone are named Tengelic Red Clay Formation and Kerecsend Red Clay Formation (Middle Pliocene to Lower Pleistocene). They occur in three types in Hungary. (1) The oldest red clays are mainly in situ weathering crusts rich in kaolinite, formed in warm, humid, subtropical or monsoon climate; (2) the younger type is rich in smectite and goethite; and (3) illite and chlorite dominant in the youngest part, which formed under warm and dry climates in savannah, steppe or forest steppe environments, and is of wind-blown origin. Representative samples were selected for study from a large number of profiles. Mineralogical, some micromorphological, and geochemical investigations of typical samples of red clays in Hungary were performed. This review focuses on the origin, development and distribution in the Pannonian basin. [Copyright &y& Elsevier]

Abstract: Loess–paleosol sequences are significant records of the mineral dust cycle of glacial–interglacial periods. As dust particles give rise to direct and indirect radiative forcing, obtaining a reliable picture of the global and regional patterns of mineral dust fluxes during glacial periods can lead to a better understanding of the contribution of mineral dust to past climate changes. Recent progress in absolute dating of loess deposits in the Carpathian Basin in East Central Europe made it possible to provide correct aeolian flux estimates for the Last Glacial period, marine isotope stage (MIS) 2. Mass accumulation rates (MARs) from chronological data of 33 loess sites exhibited a wide range of values, from 150 to 1422gm−2 a−1, centered around median and mean values of 338 and 417gm−2 a−1. and estimates have been also calculated using grain size measurements of many loess samples and loess MARs in order to facilitate comparison with models, and since particles larger than 10μm have a negligible radiative effect. Here we show that some previous model simulations of the dust cycle at the Last Glacial Maximum (LGM) significantly underestimated the real aeolian flux (ranges of our estimates: and ) in East Central Europe. For this reason, some simulations of dust-induced direct radiative forcing of the LGM climate failed to yield reliable results for this mid-latitude region as they have been based on three-dimensional dust field models that are not capable of estimating the real aeolian fluxes in Central Europe. A recent global model of top of the atmosphere (TOA) radiative forcing by mineral aerosols at the LGM that has been based on more realistic parameterization of dust sources, transport, and deposition revealed zonally averaged surface cooling of −2°C for the latitudes of our study area. This surface cooling and TOA radiative forcing (−2 to −3Wm−2) are greater than recognized in other models and draws our attention to the importance of further modeling the impact of mineral dust on LGM climate in order to gain insight into the spatial pattern of radiative forcing and better understand resulting climate response in mid-latitude loess regions such as East Central Europe. [Copyright &y& Elsevier]

Abstract: Caenorhabditis elegans has been introduced relatively late into the field of autophagy with no previous results by classical methods. Therefore, it has to be studied in parallel with both traditional electron microscopy and modern molecular approaches. In general, correct identification of autophagic elements by electron microscopy is indispensable to establish a firm basis for our understanding of the process. The principles and the method for identification, applied also for C. elegans, are summarized first in this article, to facilitate their utilization both for further studies and the analysis of new cell types and to support researchers new to electron microscopy techniques. Studying autophagy in the worm by electron microscopy has required the development of special handling and sampling techniques in addition to overcoming the general technical difficulties due to the nature of C. elegans samples. These are described in detail, together with some initial qualitative and quantitative results obtained by them. The feasibility of the presented method is supported by data which show that in continuously fed worms the autophagic compartment is in the lower range of the 10−2% order of magnitude of the cytoplasmic volume, while immediately after molting or upon starvation in the second larval period, usually more than a 10‐fold increase can be measured. In dauer larvae, individual variation of the autophagic compartment is very high. The predauer stage in daf‐2 mutants does not seem to show significant constitutive autophagic activity. Some autophagy‐related gene mutants show characteristic ultrastuctural features, such as autophagosomes with membrane abnormalities (unc‐51/Atg1) or the hypertrophy of multivesicular bodies (let‐512/Vps34, bec‐1/Atg6). [Copyright &y& Elsevier]

Studies phosphoenolpyruvate-dependent tubulin-pyruvate kinase interaction at different organization levels. Inhibitory effect of phosphoenolpyruvate on tubulin-enzyme hetero-association; Ability of pyruvate kinase to induce depolymerization of paclitaxel-destablized micorotubules into large oligometric aggregates.

Abstract: Two Cu2+-binding ligands were covalently attached to termini of short DNAs. The optimal compound of this type forms a catalytically inert complex with Cu2+. In the presence of a complementary nucleic acid the complex is decomposed forming products, which may catalyze hydrolysis of carboxylic acid esters. We have demonstrated that this process can be applied for sequence specific detection of nucleic acids. [Copyright &y& Elsevier]

Abstract: Hairpin-structured phosphorothioate oligodeoxyribonucleotides containing a singlet oxygen-sensitive linker in the loop were prepared. These compounds do not bind complementary nucleic acids in the dark. Upon irradiation with red light in the presence of chlorine e6 the linker within these compounds is cleaved and a single-stranded oligodeoxyribonucleotide is produced. The latter compound is an efficient binder of complementary nucleic acids. This is the first example of ‘caged’ phosphorothioate oligodeoxyribonucleotides, whose nucleic acid binding ability is triggered by red light. [Copyright &y& Elsevier]

Abstract Grain size proxies of aeolian dust deposits have widely been applied in environmental and sedimentary studies. However, large body of research papers are not taking into consideration that a complex grain size distribution curve cannot be an indicator of a single one environmental factor (e.g. wind speed/strength, transportation distance, aridity). The aim of the present paper is to discuss the main differences of frequently used statistical methods and to provide possible interpretations of the results by applying these various approaches on the high-resolution loess-paleosol profile of Dunaszekcső, South Hungary (Central Europe). Beside single statistical descriptors (mean, median, mode) of grain size and simple indices of size-fraction ratios (U-ratio, Grain Size Index), some more complex algorithms were also used in our paper. The applied parametric curve-fitting, end-member modelling and hierarchical cluster analysis techniques are using the whole spectrum of the measured grain size distributions and provide a more reliable and more representative results even in case of small scale variations. According to our findings, approaches which provide direct linkage among simple statistical descriptors and single atmospheric or other environmental elements are rather oversimplified as properties aeolian dust deposits are influenced by the integrated effects of several concurrent processes. Differences of more complex decomposition methods arise from the different approach and scope. End-members are determined from the unmixing based on the covariance structure of the whole grain size data-series of the section, while the parametric curve-fitting is based on the one-by-one deconvolution of the grain size distribution curves. End-members of loess-paleosol samples are regarded as representation of the average dust grain size distribution of various temporal sediment clusters of seasonal or other short-term intervals, while (sub)populations by parametric curve-fitting are proposed to illustrate process-related elements of background and dust storm depositional components for each sample. Results of cluster analysis represent similar grouping conditions as end-member modelling with a reduced sedimentary and genetically meaning. [ABSTRACT FROM AUTHOR]

The reuse of industrial by-products is important for members of numerous industrial sectors. However, though the benefits of reuse are evident from an economical point of view, some compounds in these materials can have a negative effect on users' health. In this study, the radon emanation and exhalation features of red mud were surveyed using heat-treatment (100–1200 °C). As a result of the 1200°C-treated samples, massic radon exhalation capacity reduced from 75 ± 10 mBq kg −1 h −1 to 7 ± 4 mBq kg −1 h −1 , approximately 10% of the initial exhalation rate. To find an explanation for internal structural changes, the porosity features of the heat-treated samples were also investigated. It was found that the cumulative pore volume reduced significantly in less than 100 nm, which can explain the reduced massic exhalation capacity in the high temperature treated range mentioned above. SEM snapshots were taken of the surfaces of the samples as visual evidence for superficial morphological changes. It was found that the surface of the high temperature treated samples had changed, proving the decrement of open pores on the surface. [ABSTRACT FROM AUTHOR]

Abstract: The potential use of natural antioxidants for polyolefin stabilisation came into the centre of attention because of some doubts about the effects of the reaction products of synthetic phenolic antioxidants on human health. The effect of curcumin on the melt stability of polyethylene was investigated in this paper with and without a phosphonite stabiliser by using multiple extrusions. Irganox 1010 was applied as reference phenolic antioxidant. Curcumin was characterised by FT-IR and UV–VIS spectroscopy, as well as by thermal analysis. Its stabilisation efficiency was determined by measuring the chemical structure, the rheological properties, the residual thermo-oxidative stability, and the colour of the polymer. The results reveal that the melt stabilising efficiency of curcumin is superior to that of the synthetic antioxidant investigated and is further enhanced by the addition of the phosphonite secondary antioxidant. The changes in the characteristics of the polymer indicate that besides the phenolic OH groups also the linear linkage between the two methoxyphenyl rings of curcumin participates in the stabilisation reactions. [Copyright &y& Elsevier]

Abstract: Nanocomposites were prepared from sodium montmorillonite (NaMMT) and organoclays (OMMT) with different particle sizes as a function of silicate content. Composite structure was characterized by various methods including X-ray diffraction (XRD), scanning electron microscopy (SEM) and rheology. Model calculations were carried out to estimate the thickness and yield stress of the interphase forming in the composites. The results proved the formation of an interphase, but the determination of interphase properties was hampered by several factors. First of all, the particle size of the filler changed quite considerably in PP/OMMT composites in spite of earlier observations and expectations. Particle characteristics changed even further when a relatively small amount (5vol.%) of functionalized polymer (MAPP) was added to the composite. As a consequence, the estimation of the contact surface between the silicate and the polymer became extremely difficult. In spite of the uncertainties overall values of interphase properties were obtained using the results of all composites prepared. The prediction for the average thickness of the interphase is 0.23μm and we obtained 51.2MPa for interphase yield stress, but this estimate neglects the different interactions developing in composites containing the uncoated and the modified silicate, respectively. [Copyright &y& Elsevier]

• Three fluvial phases identified in the Sió valley floor (Transdanubia, Hungary). • First evidence for large-scale meanders in Transdanubia in the Late Pleniglacial. • Isolation by loess hills favored formation of anabranching channels ~18000 cal. BP. • Small meanders formed by incision, evolved in the Holocene in aggradation conditions. • The fluvial phases differ in timing and type of planform in other rivers of Europe. Knowledge about the evolution of rivers planforms in loess landscapes of Europe is incomplete. While there are studies on river evolution conducted in loess areas of central and western Europe, the area of Transdanubia (Hungary) remains poorly recognized. Our research work extends previous findings by studying a unique example of alluvial fill maintaining a sedimentary record of river planforms from the Late Pleistocene to the modern times (the Sió Valley, Hungary). The main goal was to determine the main fluvial phases shaping the valley floor. Our study was based on geological, geophysical and remote sensing methods supported by AMS radiocarbon and OSL dating. Three fluvial phases were identified: the formation of large-scale meanders in the Late Peniglacial, transition to an anabranching pattern ~18000 cal. BP, and formation of small-scale meanders ~12700 cal. BP. Their traces are present in the sedimentary record of other rivers evolving in loess landscapes, however, their appearance differs in the timing and type of river planform changes. Phase I was marked by large-scale meanders in the Great Hungarian Plain and Transdanubia, and braided rivers in western Europe. Phase II, marked by transitions to anabranching planforms, or periods of meander cutoffs, appeared first in the Late Pleniglacial in isolated valleys of Transdanubia and northern part of the Pannonian basin. The latest appearance of this phase took place in western Europe owing to a cooler climate and sparse vegetation compared to Transdanubia and Great Hungarian Plain. Phase III, marked by transitions from anabranching rivers to small-scale meanders, started in the Sió valley in conditions of sediment deficit causing river bed incision. Aggradation appeared owing to anthropogenic influence starting ~7000 cal. BP. Its maximum occurred 3000–4000 cal. BP. This triggered phase III in western Europe, and increased deposition of fines, resulting in flow discontinuation in some valleys of Transdanubia. [ABSTRACT FROM AUTHOR]

The research investigated three iron carbonate (siderite) sedimentary concretions from Nagykovácsi, Úri and Délegyháza, Hungary. To identify possible source rocks and effects of the glaze-like exposed surface of the concretions, we carried on comparative petrological, mineralogical, geochemical and isotopic studies. The samples were microbially mediated siderite concretions with embedded metamorphous and igneous mineral clasts, and had specific rim belts characterized by semi-concentric outer Fe-oxide layers, fluffy pyrite-rich outer belts and siderite inner parts. We investigated the cross section of the Fe-carbonate concretions by independent methodologies in order to identify their rim effects. Their surficial oxide layers showed evidence of degassing of the exposed surface caused most probably by elevated temperatures. The inner rim pyrite belt in the concretions excluded the possibility of a prolonged wet surface environment. Microtextural and mineralogical features did not support desert varnish formation. 10 Be nuclide values of the Nagykovácsi and Uri concretions were far above the level of terrestrial in - situ cosmogenic nuclides, but they were consistent with the lowest levels for meteorites. Though the data were not conclusive to confirm any kind of known origin, they are contradictary, and open possibilities for a scenario of terrestrial meteorite origin. [ABSTRACT FROM AUTHOR]

The Pliocene and Early Pleistocene (5.2–1 Ma) palaeoclimate for localities in Italy is evaluated using stable carbon and oxygen isotope compositions of tooth enamel of fossil specimens from Rhinocerotidae ( Stephanorhinus sp.) and Gomphotheriidae ( Anancus sp.) taxa. Carbon isotope composition was measured in the structural carbonate (δ 13 C), while oxygen isotope values were determined both in the structural carbonate (δ 18 O CO3 ) and the phosphate (δ 18 O PO4 ) of bioapatite. The δ 13 C CO3 values indicate that the taxa were grazers-browsers of a pure C 3 vegetation. Low δ 13 C CO3 values for Central and North Italy indicate a humid climate with woodlands and forest cover in the Pliocene. For northern localities the δ 13 C values increase between MN16a and MNQ16b biozones most likely linked to the Northern Hemisphere Glaciation at 2.7 Ma after the “Mid-Pliocene Warm Period”. For Central Italy the values have a wide range with a long term increasing trend in the Early Pleistocene, indicating more arid climate and/or more open vegetation. Overall, the δ 18 O PO4 values in Central Italy change together with the δ 13 C CO3 values and are taken to reflect the warmer/wetter interglacials and cooler/more arid glacial phases. The δ 18 O PO4 values in North Italy are lower than those in Central Italy and show no clear temporal trend. One explanation for the low values especially in MN14-15 biozone is that these δ 18 O PO4 values do not reflect entirely the isotopic composition of local precipitation but river waters from the Alps with 18 O-depleted isotopic compositions or a N-S directed rain-shadow effect on the precipitation. In general the new isotope data agree well with palaeoclimate reconstructions based on palynological and other proxies. [ABSTRACT FROM AUTHOR]

A series of PF-co-doped titanium dioxide (PF-TiO 2 ) samples with various PF contents were synthesized hydrothermally at 250 °C and systematically investigated by means of X-ray diffraction, X-ray photoelectron spectroscopy and electron microscopy. For the PF-co-doping of TiO 2 , hexafluorophosphoric acid (HPF 6 ) was used. Increasing HPF 6 concentration did not decrease the crystallinity of the synthesized samples, but the dopant concentration strongly influenced the size and morphology of the PF-TiO 2 nanoparticles. The undoped TiO 2 consisted of polymorphic and polydisperse nanoparticles, whereas smaller, predominantly spherical particles were observed for the PF-TiO 2 samples. Diffuse reflectance UV–vis spectroscopy revealed that PF-TiO 2 exhibited a slightly higher band gap energy than that of undoped TiO 2 . Despite this blue-shift in absorption edge, the photocatalytic activity of PF-TiO 2 was higher than that of undoped TiO 2 even under visible light irradiation. The effects of the dopant concentration on the structure and photocatalytic activity are discussed in detail. [ABSTRACT FROM AUTHOR]

As revealed by 18 AMS radiocarbon and 24 OSL/IRSL ages the Dunaszekcső loess-paleosol sequence is an excellent terrestrial record of paleoenvironmental change in the Carpathian Basin for the last 130 ka, with significant soil forming episodes during the Eemian interglacial (130–115 ka, MIS 5e) and in some subsequent MIS 5 stages, and distinct periods of loess accumulations during the MIS 4 and MIS 2. Charcoals from the sequence made it possible to test the accuracy of 14 C ages from mollusc shells. This approach revealed that 14 C ages from some gastropods having small shells (<10 mm) ( Succinella oblonga , Vitrea crystallina ) are statistically indistinguishable from the ages of charcoals, while others (Clausiliidae sp., Chondrula tridens ) show age anomalies up to 600–800 years. OSL and pIRIR@290 ages are found to be consistently older, while post-IR OSL ages are younger than the 14 C ages from charcoals and molluscs by some thousands of years, except for pIRIR@225 ages that match the radiocarbon ages quite well. OSL and IRSL ages have scatters up to 7–10 thousand years within 40 ka, while charcoals and small molluscs yield consistent ages with relatively low variability. Beyond the observation that some small molluscs seem to yield reliable 14 C ages, calibrated 2 σ age ranges of the radiocarbon data (ca 500–800 years for 20 to 30 ka) are an order of magnitude narrower than those of the OSL/IRSL methods (1800–4000 years for 25 to 35 ka). Thus, for establishing chronologies within 40 ka, which are both accurate and precise enough to address issues like synchroneity of millennial-scale paleoenvironmental events across regions (e.g. North Atlantic and Europe), AMS radiocarbon dating of shells of specific loess molluscs and charcoals may probably be a powerful chronological tool. However, additional work is definitely required involving 14 C and OSL/IRSL dates from other loess sequences to further test the performance of these two supposedly robust chronometers. [ABSTRACT FROM AUTHOR]

Abstract: The Paks loess-paleosol sequence is one of the most important terrestrial records of Middle and Late Pleistocene environmental changes in East Central Europe, spanning the last ca. 0.8Ma. While geochemical proxies demonstrate a general decreasing chemical weathering trend over the last 0.8Ma in the Carpathian Basin, mineralogy and derived indices reflect intensifying physical erosion. In theory, the observed chemical weathering trend can be accounted for both by enhanced input of relatively unweathered material and by climate deterioration during the Quaternary, as the proxies such as CIA are not capable of distinguishing between pre- and post-depositional weathering. Enhanced physical erosion of the source areas, driven by tectonism, and resulting increased sedimentation of fresh mineral dust at the depositional site are demonstrated by increasing dolomite, illite and chlorite contents and sme/ill, sme/(ill+chl) ratios from older to younger sediments in the profile, together with increasing thickness of loess layers towards the youngest part of the sequence. At the same time, constant smectite contents (30–40%) in paleosols appear to disprove progressive aridization of interglacials through time and suggest that the duration of pedogenesis played an important role in determining soil types. Further, the increasing proportion of inherited phyllosilicates (illite and chlorite) would, in theory, raise the possibility that the decreasing values of chemical weathering indices are just artifacts of enhanced physical erosion and resulting increased dust deposition by a dilution effect. The above findings highlight the fact that the general view on chemical weathering is oversimplistic, as its ‘equation’ includes two basic variables, tectonism and time beyond climate and the interplay of these equally important factors will eventually determine its final value. To get a better grasp of these processes needs further data (more age control in loess profiles, data on uplift in and around sedimentary basins) and more sophisticated proxies, as the mineralogical data presented here can be considered only semiquantitative. Regarding the provenance of sediments in the Paks profile, geochemical data demonstrate that felsic rocks dominated the source areas and there have been only very little variations in provenance over the last ca. 0.8Ma. Significant contributions from mafic/ultramafic rocks to the sediments can be ruled out as revealed by lower abundances of ferromagnesian trace elements. The appearance of amphiboles and high dolomite contents suggest that loess material was at least partly sourced from local rocks and geochemical data reveal a genetic link between floodplain sediments and loess deposits. [Copyright &y& Elsevier]

The disordered tubulin polymerization promoting protein (TPPP/p25) was found to be co-enriched in neuronal and glial inclusions with α-synuclein in Parkinson disease and multiple system atrophy, respectively; however, co-occurrence of α-synuclein with β-amyloid (Aβ) in human brain inclusions has been recently reported, suggesting the existence of mixed type pathologies that could result in obstacles in the correct diagnosis and treatment. Here we identified TPPP/p25 as an interacting partner of the soluble Aβ oligomers as major risk factors for Alzheimer disease using ProtoArray human protein microarray. The interactions of oligomeric Aβ with proteins involved in the etiology of neurological disorders were characterized by ELISA, surface plasmon resonance, pelleting experiments, and tubulin polymerization assay. We showed that the Aβ(42) tightly bound to TPPP/p25 (K(d) = 85 nm) and caused aberrant protein aggregation by inhibiting the physiologically relevant TPPP/p25-derived microtubule assembly. The pair-wise interactions of Aβ(42), α-synuclein, and tubulin were found to be relatively weak; however, these three components formed soluble ternary complex exclusively in the absence of TPPP/p25. The aggregation-facilitating activity of TPPP/p25 and its interaction with Aβ was monitored by electron microscopy with purified proteins by pelleting experiments with cell-free extracts as well as by confocal microscopy with CHO cells expressing TPPP/p25 or amyloid. The finding that the interaction of TPPP/p25 with Aβ can produce pathological-like aggregates is tightly coupled with unusual pathology of the Alzheimer disease revealed previously; that is, partial co-localization of Aβ and TPPP/p25 in the case of diffuse Lewy body disease with Alzheimer disease. [ABSTRACT FROM AUTHOR]

Abstract: The occurrence, shape, structure and eruption style of monogenetic volcanoes, such as maars, tuff rings, tuff cones and scoria cones, are generally governed by several internal (composition of the magma, magmatic flux, ascent rate, viscosity, volatile contents) and external conditions (regional and local tectonics, topography, and the presence of surfacial, ground and meteoric water). These controlling factors are together responsible for the eruption style, distribution pattern, volcanic facies architecture and morphology of the monogenetic volcanic landforms. The Late Miocene to Pleistocene Bakony–Balaton Highland Volcanic Field (BBHVF) in western Hungary is a typical small sized (<50 eruption centres), basaltic, intraplate “monogenetic” volcanic field. Generally, initial eruptions of the BBHVF were phreatomagmatic (n=~28); however, a lesser number (n=~14) of predominantly scoria cone forming eruptions are also inferred. The temporal distribution of the Strombolian style scoria cones was concentrated mostly between 3 and 2.5Ma. A detailed study of the changes in eruption styles recorded in the pyroclastic sequences suggested a change from a conventional phreatomagmatic to a magmatic fragmentation style during the activity of the volcanic field. A clear correlation has been identified between the long-term environmental changes of the region that resulted in a gradual shift from a more phreatomagmatic eruption style to a more magmatic eruption style. Detailed examination of the temporal distribution of K–Ar and Ar–Ar radiometric data, Digital Elevation Model and Dense Rock Equivalent-based volume calculations of eruptive products and origin of pyroclastic rocks (e.g. phreatomagmatic or magmatic) preserved in variously eroded monogenetic volcanoes were utilized to integrate available volcanological and climatological data to identify potential links between external and internal controlling parameters that responsible for long-term eruption style changes. At least 6 volcanic cycles have been identified by cluster analysis. Time gap between the cycles were vary from 1.66 up to 0.06Ma, while the average eruption recurrence rate was ~0.1078Ma/event. The time-volume diagram of the volcanism of BBHVF have shown time-predictive behavior combined with low magma-flux (total preserved volume ~2.867km3) and output rates (0.53km3/Ma for the entire volcanic field and 0.90km3/Ma for the last 5cycles), suggesting that volcanism was largely tectonically-controlled and not magmatically-controlled. Furthermore, the topographic differences between the northern (“elevated”) and southern (“basin-like”) parts of the volcanic field, are also important in local differences in dominant fragmentation style, because the elevated part of the field was prone to host large, more magmatically-evolved volcanoes, than on the lower, water-saturated, unconsolidated sediments, which favored to the magma/water interaction driven phreatomagmatic fragmentation. The third controlling parameter, which seems to play an important role in controlling the eruptive style of monogenetic volcanism at BBHVF, was the paleoclimate fluctuation, especially during the time interval of 3.0 to 2.5Ma. Thus, mainly the long-term environmental changes (e.g. aridification) have been response the shifting fragmentation style from phreatomagmatic to more magmatic ones. [Copyright &y& Elsevier]

Abstract: Recently exosomes have been shown to play important roles in several immune phenomena. These small vesicles contain MHC proteins along with co-stimulatory and adhesion molecules, and mediate antigen presentation to T cells. In the present study we show that upon incubation with autologous serum, murine macrophages and B cells – but not T lymphocytes – fix C3-fragments covalently to the cell membrane and release them on exosomes in a time dependent fashion. While in the case of human B lymphocytes CR2 has been shown to serve as the main C3b-acceptor site, here we clearly demonstrate that cells derived from CR1/2 KO animals also have the capacity to fix C3b covalently. This finding points to a major difference between human and murine systems, and suggests the existence of additional acceptor sites on the cell membrane. Here we show that C3-fragment containing exosomes derived from OVA loaded antigen presenting cells induce a significantly elevated T cell response in the presence of suboptimal antigen stimulus. These data reveal a novel function of cell surface-deposited C3-fragments and provide further evidence for the role of exosomes secreted by antigen presenting cells. Since fixation of C3b to plasma membranes can be substantial in the presence of pathogens; moreover tumor cells are also known to activate the complement system resulting in complement-deposition, C3-carrying exosomes released by these cells may play an important immunomodulatory role in vivo, as well. [Copyright &y& Elsevier]

Tubulin polymerization-promoting protein (TPPP), an unfolded brain-specific protein interacts with the tubulin/microtubule system in vitro and in vivo, and is enriched in human pathological brain inclusions. Here we show that TPPP induces tubulin self-assembly into intact frequently bundled microtubules, and that the phosphorylation of specific sites distinctly affects the function of TPPP. In vitro phosphorylation of wild type and the truncated form (Δ3-43TPPP) of human recombinant TPPP was performed by kinases involved in brain-specific processes. A stoichiometry of 2.9 ± 0.3,2.2 ± 0.3, and 0.9 ± 0.1 mol P/mol protein with ERK2, cyclin-dependent kinase S (Cdk5), and cAMP-dependent protein kinase (PKA), respectively, was revealed for the full-length protein, and 0.4–0.5 mol P/mol protein was detected with all three kinases when the N-terminal tail was deleted. The phosphorylation sites Thr14, Ser18, Ser160 for Cdk5; Ser18, Ser16° for ERK2, and Ser32 for PKA were identified by mass spectrometry. These sites were consistent with the bioinformatic predictions. The three N-terminal sites were also found to be phosphorylated in vivo in TPPP isolated from bovine brain. Affinity binding experiments provided evidence for the direct interaction between TPPP and ERK2. The phosphorylation of TPPP by ERK2 or Cdk5, but not by PKA, perturbed the structural alterations induced by the interaction between TPPP and tubulin without affecting the binding affinity (Kd = 2.5–2.7 μM) or the stoichiometry (1 mol TPPP/mol tubulin) of the complex. The phosphorylation by ERK2 or Cdk5 resulted in the loss of microtubule-assembling activity of TPPP. The combination of our in vitro and in vivo data suggests that ERK2 can regulate TPPP activity via the phosphorylation of Thr14 and/or Ser18 in its unfolded N-terminal tail. [ABSTRACT FROM AUTHOR]