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  • Author or Editor: Ágnes Farkas x
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A biomassza előállításának és energetikai célú hasznosításának társadalmi hatásai a szakértők által leírtak alapján rendkívül pozitívnak mutatkoztak. Az elmúlt tíz év adatait alapul véve mindez nem jelenthető ki egyértelműen, tekintettel arra, hogy a statisztikai adatok elemzése bizonyos esetekben nem támasztja alá a korábbi tanulmányokban leírtakat.A biomassza energetikai célú hasznosítása ugyan képes munkahelyeket teremteni — a szántóföldeken, az erdőgazdálkodásban, a logisztikában, valamint az erőművekben — és emelni a térségek életszínvonalát, azonban az alacsony képzettségűek számára csak szezonális foglalkoztatást biztosít. Az előirányzott hatások megkérdőjelezhetőségét vetíti előre továbbá, hogy az elmúlt évek és napjaink migrációs adatait vizsgálva az idősorelemzés eredményei alapján sem történt érdemi változás.Összességében a biomassza társadalmi hatásai elmaradnak a várakozásoktól, aminek számos oka lehet; egyrészt a hatások hosszabb távon jelenthetnek pozitív változást, másrészt napjainkban túl optimisták a várakozások, továbbá globális és egyes regionális változók dominálják a biomassza társadalmi hatásait.

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The author provides new data for the paleontological and stratigraphic understanding of the Upper Cretaceous formations of the Crimean Peninsula. Within the classic Bakhchisaray region 24 samples from six sections (Cenomanian-Maastrichtian) were studied. About 130 palynomorphs have been identified, 11 associations (spore-pollen and dinoflagellate) were differentiated and correlated with nannozones, foram zones and macropaleontological zones. The study confirms that during the Senonian the Crimean Peninsula belonged to the northern nearshore-neritic region of the Tethys and on land to the boreal Normapolles Phytogeographic Province.

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A megújuló energiahordozók közül Magyarországon a biomassza nyújtja az egyik legígéretesebb lehetőséget a fosszilis energiaforrások részleges kiváltására. Jelen tanulmányban az elméleti gazdaságtan, a statisztika és a társadalomtudományok eszköztárával elemezzük a biomassza munkaerőpiacát. A munkaerő-piaci kereslet nem minden esetben egyezik meg a kínálattal. A szűkülő lehetőségek következtében a biomassza népességmegtartó képessége sem érvényesül minden esetben. A magyar piacon szakemberhiány van, így a kvalifikált alkalmazottak naponta ingáznak otthonuk és munkahelyük között. Ennek oka elsősorban abban rejlik, hogy az oktatási rendszer nem képes kellő arányban kinevelni magasan képzett, ökoenergetikai ismeretekkel rendelkező szakembereket. A lokális munkaerőt igénylő szántóföldi munka a képzetlen munkaerő számára jelenthet egyfajta kitörési lehetőséget. A munkaerő-piaci diszkrimináció – amely a kék-, valamint a fehérgalléros alkalmazottakat egyaránt érinti – és az oktatási rendszer hiányosságai egyértelműen a paradigmaváltás szükségességét irányozzák elő. A 2011–2012-es reformok ez idáig nem hoztak számottevő változást az ökoenergetika számára, így kiemelkedően fontos lenne a megújuló energiaforrások hasznosításával foglalkozó szakok arányának növelése. Amennyiben az intézmények átszervezésén kívül nem történik lényegi, gondolkodásmódbeli változás, feltehetően a biomassza-alapú energiatermelés sem fogja elérni a kívánt szintet. A biomasszapiac nem érvényesülhet szárnyaló mezőgazdasági ágazat nélkül.

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The Senonian succession of the Szilvágy-33 well in the Northern Zala Basin was investigated in order to re-evaluate its chronostratigraphic subdivision and depositional history. The studied sequence begins with the Ajka Formation of reduced thickness and atypical facies. This is followed by the Jákó Formation with the interfingering layers of the Ugod Limestone, and then the approximately 300 m-thick section of the Ugod Limestone which is covered by the Polány Marl. According to the palynologic and nannoplankton investigations, the entire encountered sequence can be assigned to the Campanian. The layers assignable to the Ajka Formation contain the sporomorph assemblage known from the upper section of the Jákó Formation in the Bakony basins, clearly indicating a considerable temporal shift of the lithofacies during transgression. The late transgression demonstrated in the Szilvágy-33 well suggests an elevated paleotopography. In contrast to the former assumptions, the transgression may not have reached the Bakony region via the Zala Basin; rather, both sub-areas were invaded by the sea from the South Alpine pelagic basins.

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The morphology and histology of the cyathial nectary were studied in 8 European leafy spurge (Euphorbia) species, revealing that certain histological traits of the glands are in close correlation to each species’ habitat, underlining the importance of morphological evidences in determining relevant ecological tolerance spectra of plants.The structure of the cyathial glands was studied in longitudinal sections with light microscopy, and histological parameters were measured and statistically analyzed by appropriate softwares.The nectaries consist of a cuticle-covered epidermis, formed by palisade cells, under which the glandular tissue and parenchyma are composed of isodiametric and anisodiametric cells in all species. Thickness of cuticle, position of nectary stomata and number of rows comprising the glandular tissue vary to a great extent in plants living in xeric, humid or mesic habitats.Although all the studied anatomical features of the nectaries were expected to be in correspondence with the characteristics of habitat types, we have only found the number of glandular cell rows to be in strong correlation with the Ellenberg’s ecological indicator values on soil moisture, which varied with species. The recorded anatomical differences among the studied Euphorbia taxa emphasize the ecological significance of glandular tissue in plant adaptation, which can also be relevant for systematic purposes.

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This paper presents the system of Old Hungarian expressions conveying universal or maximal readings, as found in Old Hungarian codices. The main empirical findigs are that (i) the OH suffix-keed could be a (temporal) universal quantifier. Expressions with such suffixes can help reconstruct quantifiers from the head-final stage of Hungarian. (ii) Old Hungarian had bare pronouns that acquired a bound, quantificational reading from long-distance operators. Against such a background, minden is claimed to be a quintessential strong D-quantifier: It could undergo raising, and its scope was flexible (within syntactic islands). (iii) These properties of minden are distinctive within the class of particle + indeterminate pronoun complexes (such as vala-ki lit. ‘vala-who’, ‘somebody’), which could be said to lack quantificational force.

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Laboratory diagnosis of Acanthamoeba keratitis in Hungary

Acanthamoeba species are free-living amebae that can be found in almost every range of environments. Within this genus, numerous species are recognized as human pathogens, potentially causing Acanthamoeba keratitis (AK). AK is a corneal disease that is predominantly associated with contact lens use, the epidemiology of which is related to the specific genotype of Acanthamoeba. This study reports seven (7/16; 43.75%) positive cases. Detection of Acanthamoeba in corneal scrapings is based on cultivation and polymerase chain reaction (PCR) combined with the molecular taxonomic identification method. By PCR, seven samples were positive; cultivation was successful for five samples, probably because of the low quantity of samples. Genotype identification was carried out with a real-time fluorescence resonance energy transfer PCR assay based on sequence analysis of the 18S rRNA gene, and sensitivity and specificity were evaluated in comparison with traditional parasitological techniques. All seven detected Acanthamoeba strains belonged to the T4 genotype, the main AK-related genotype worldwide. These results confirmed the importance of a complete diagnostic protocol, including a PCR assay, for the clinical diagnosis of AK from human samples. Genotyping allowed the identification of all isolates in the T4 group, thus demonstrating the prevalence of this genotype in Hungary.

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(Artemia) nauplii was used to asses the toxicity of rotenone, MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine), MP+ (1-methyl-4-phenylpyridinium) and the effect of L-DOPA co-treatment with rotenone. Rotenone had a dose dependent effect on mortality (LC50: 0.37 ± 0.04 μM mean ± S E, n = 24), while MPTP and MP+ proved to be toxic in millimolar range (LC50: 0.21 ± 0.09 mM and 0.20 ± 0.08 mM, respectively, n = 4). L-DOPA (50–200 μM) co-treatment increased the survival of the rotenone-treated animals (LC50: 0.51 ± 0.23 μM, 1.03 ± 0.66 μM, and 0.76 ± 0.52 μM, respectively). In the whole body tissue homogenates of Artemia, sublethal (up to 0.3 μM) concentrations of rotenone increased the glutathione S-transferase (GST) activity by up to 50 about percent (LC50: 53.3 ± 6.8 nM/min/mg protein, against 34.7 ± 3.6 nM/min/mg protein, n = 4). Nauplii treated in 100 mM L-DOPA and rotenone together showed further increase of GST activity all across the range of rotenone concentrations. These results on Artemia nauplii show similarities with other animal models, when complex I inhibitors were tested. Biochemical measurements suggest a protective role of L-DOPA by increasing the GST activity as part of the intracellular defences during toxin-evoked oxidative stress.

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The responses of the snail central neurons (Helix pomatia, Lymnaea stagnalis) and the isolated Helix heart were characterized evoked by cyanobacterial extracts (Cylindrospermopsis raciborskii ACT strains) isolated from Lake Balaton (Hungary). The nicotinergic acetylcholine (ACh) receptors in the CNS (both excitatory and inhibitory) were blocked by the extracts of ACT 9502 and ACT 9505 strains and the anatoxin- a (homoanatoxin-a) producing reference strain of Oscillatoria sp. (PCC 6506), similar to the inhibitory effects of the pure anatoxin-a. The enhancement of the ACh responses by the ACT 9504 extract suggests additional, probably acetylcholine esterase inhibitory mechanisms. On the isolated Helix heart the crude ACT 9505 and PCC 6506 extracts evoked frequency increase and transient twitch contraction, opposite to the ACh evoked heart relaxation. Anatoxin-a similarly contracted the heart but did not increase its contration frequency. These data suggest the involvement of some non-cholinergic mechanisms, acting very likely by direct modulation of the electrical or contractile system of the isolated heart. Diversity of the effects evoked by the cyanobacterial extracts in the CNS and heart suggest pharmacologically different neuroactive components among the secondary metabolites of the cyanobacteria acting on both (anatoxin-a like) cholinergic and (unidentified) non-cholinergic receptors.

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Simple real-time PCR assay with one set of primer and probe for rapid, sensitive qualitative and quantitative detection of Entamoeba histolytica has been used. Consensus sequences were used to amplify a species-specific region of the 16S rRNA gene, and fluorescence resonance energy transfer hybridization probes were used for detection in a LightCycler platform (Roche). The anchor probe sequence was designed to be a perfect match for the 16S rRNA gene of Entamoeba species, while the acceptor probe sequence was designed for Entamoeba histolytica, which allowed differentiation. The performed characteristics of the real-time PCR assay were compared with ELISA antigen and microscopical detection from 77 samples of individuals with suspected clinical diagnosis of imported E. histolytica infection. Stool and liver abscess pus samples were examined with analytical sensitivity of 5 parasites per PCR reaction. The melting curve means Tms (standard deviation) in clinical isolates were 54°C. The real-time assay was 100% sensitive and specific for differentiation of Entamoeba histolytica, compared with conventional ELISA or microscopy. This real-time PCR assay with melting curve analysis is rapid, and specific for the detection and differentiation of Entamoeba histolytica. The suitability for routine use of this assay in clinical diagnostic laboratories is discussed.

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