14 research outputs found

    Assessment of the Ecotoxicity of Nanoplastics

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    The presence of micro- and nanoplastics in aquatic environments (including freshwater and marine ecosystems as well as their sediments) is becoming an increasingly serious problem worldwide. A wide range of studies have addressed the ecological effects these particles pose on biota. The main exposure pathway are food chains, e.g. under laboratory conditions these particles accumulate in the brain tissues of fish that feed on zooplankton causing brain damage. These studies, however, report mainly on the physical effects. In order to establish actual ecotoxicological effects, nanoplastics (50 nm in diameter) were assessed using the Vibrio fischeri bioluminescence inhibition bioassay (VFBIA). Our results showed that even environmentally relevant concentrations might trigger ecotoxicological effects. This study can be con- sidered to be a first screening, however, results indicate the need for more complex testing on a battery of aquatic test organisms

    Az adverbiumok mondattani és jelentéstani kérdései = The syntax and syntax-semantics interface of adverbial modification

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    A határozószók és a határozók alaktani, mondattani és funkcionális kérdéseit vizsgáltuk a generatív nyelvelmélet keretében, főként magyar anyag alapján. Olyan leírásra törekedtünk, melyből a különféle határozófajták mondattani viselkedése, hatóköre, valamint hangsúlyozása egyaránt következik. A különféle határozótípusok PP-ként való elemzésének lehetőségét bizonyítottuk. A határozók mondatbeli elhelyezése tekintetében a specifikálói pozíció (Cinque 1999) ellen és az adjunkciós elemzés (Ernst 2002) mellett érveltünk. Megmutattuk, hogy a határozók szórendjének levezetéséhez bal- és jobboldali adjunkció feltételezése egyaránt szükséges. A különféle határozófajták szórendi helyét mondattani, jelentéstani és prozódiai tényezők összjátékával magyaráztuk. A jelentéstani tényezők között pl. a határozók inkorporálhatóságát korlátozó típusmegszorítást, a negatív határozók kötelező fókuszálását előidéző skaláris megszorítást, egyes határozófajták és igefajták komplex eseményszerkezetének inkompatibilitását vizsgáltuk. Az ige mögötti határozók szórendjét befolyásoló prozódiai tényező például a növekvő összetevők törvénye. Megfigyeltük az intonációskifejezés- újraelemzés kiváltódásának feltételeit és jelentéstani következményeit is. A helyhatározói igekötők egy típusát a mozgatási láncok sajátos fonológiai megvalósulásaként (a fonológiailag redukált kópia inkorporációjaként) elemeztük. A tárgykörben mintegy 60 tanulmányt publikáltunk. Adverbs and Adverbial Adjuncts at the Interfaces (489 old.) c. könyvünket kiadja a Mouton de Gruyter (Berlin). | This project has aimed to clarify (on the basis of mainly Hungarian data) basic issues concerning the category "adverb", the function "adverbial", and the grammar of adverbial modification. We have argued for the PP analysis of adverbials, and have claimed that they enter the derivation via left- and right-adjunction. Their merge-in position is determined by the interplay of syntactic, semantic, and prosodic factors. The semantically motivated constraints discussed also include a type restriction affecting adverbials semantically incorporated into the verbal predicate, an obligatory focus position for scalar adverbs representing negative values of bidirectional scales, cooccurrence restrictions between verbs and adverbials involving incompatible subevents, etc. The order and interpretation of adverbials in the postverbal domain is shown to be affected by such phonologically motivated constraints as the Law of Growing Constituents, and by intonation-phrase restructuring. The shape of the light-headed chain arising in the course of locative PP incorporation is determined by morpho-phonological requirements. The types of adverbs and adverbials analyzed include locatives, temporals, comitatives, epistemic adverbs, adverbs of degree, manner, counting, and frequency, quantificational adverbs, and adverbial participles. We have published about 60 studies; our book Adverbs and Adverbial Adjuncts at the Interfaces (pp. 489) is published in the series Interface Explorations of Mouton de Gruyter, Berlin

    Neurobiochemical changes in the vicinity of a nanostructured neural implant

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    Neural interface technologies including recording and stimulation electrodes are currently in the early phase of clinical trials aiming to help patients with spinal cord injuries, degenerative disorders, strokes interrupting descending motor pathways, or limb amputations. Their lifetime is of key importance; however, it is limited by the foreign body response of the tissue causing the loss of neurons and a reactive astrogliosis around the implant surface. Improving the biocompatibility of implant surfaces, especially promoting neuronal attachment and regeneration is therefore essential. In our work, bioactive properties of implanted black polySi nanostructured surfaces (520–800 nm long nanopillars with a diameter of 150–200 nm) were investigated and compared to microstructured Si surfaces in eightweek- long in vivo experiments. Glial encapsulation and local neuronal cell loss were characterised using GFAP and NeuN immunostaining respectively, followed by systematic image analysis. Regarding the severity of gliosis, no significant difference was observed in the vicinity of the different implant surfaces, however, the number of surviving neurons close to the nanostructured surface was higher than that of the microstructured ones. Our results imply that the functionality of implanted microelectrodes covered by Si nanopillars may lead to improved long-term recordings

    Birds as potential reservoirs of tick-borne pathogens: first evidence of bacteraemia with Rickettsia helvetica

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    BACKGROUND Birds have long been known as carriers of ticks, but data from the literature are lacking on their role as a reservoir in the epidemiology of certain tick-borne disease-causing agents. Therefore, the aim of this study was to evaluate the presence of three emerging, zoonotic tick-borne pathogens in blood samples and ticks of birds and to assess the impact of feeding location preference and migration distance of bird species on their tick infestation. METHODS Blood samples and ticks of birds were analysed with TaqMan real-time PCRs and conventional PCR followed by sequencing. RESULTS During the spring and autumn bird migrations, 128 blood samples and 140 ticks (Ixodes ricinus, Haemaphysalis concinna and a Hyalomma specimen) were collected from birds belonging to 16 species. The prevalence of tick infestation and the presence of tick species were related to the feeding and migration habits of avian hosts. Birds were shown to be bacteraemic with Rickettsia helvetica and Anaplasma phagocytophilum, but not with Candidatus Neoehrlichia mikurensis. The prevalence of rickettsiae was high (51.4%) in ticks, suggesting that some of them may have acquired their infection from their avian host. CONCLUSION Based on the present results birds are potential reservoirs of both I. ricinus transmitted zoonotic pathogens, R. helvetica and A. phagocytophilum, but their epidemiological role appears to be less important concerning the latter, at least in Central Europe
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