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  • Author or Editor: Károly Kovács x
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In 2011 Hungary's water supply and sanitation sector was characterized by a multitude of utilities, a fragmented market with widely differing tariffs and no centralized regulation, resulting in often inefficient and unsustainable operational and market conditions. In 2011 the Hungarian government introduced the Act CCIX of 2011 on Water Utility Services which resulted in significant market consolidations. In this article we present the results of a qualitative survey carried out in 2015 to examine the opinion of top managers of utilities on the short and midterm effects of the realization of the objectives set by the Act. The interviews focused on examining the efficiency changes experienced by 15 CEOs of different water utility service provider companies since the integration. The paper also examines their expectations for the future across a multitude of technical and economic fields and factors. This qualitative research aimed to study whether the recent changes in policy and market structure led to economies of scale and to the perceptible increase of technical and economic efficiency levels. It was concluded that efficiency benefits of economies of scale prevailed in most cases, however, these were perceived only to a limited extent at the time of the survey, approximately midway through the ongoing integration processes.

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Eutrophication and enhanced external nutrient loading of lakes and seas are most clearly reflected by increased cyanobacterial blooms, which are often toxic. Freshwater cyanobacteria produce a number of bioactive secondary metabolites, some of which have allelopathic properties, significantly influencing the biological processes of other algae, thereby affecting species composition and succession of the phytoplankton. The goal of this work was to investigate the influence of bloom-forming cyanobacterial exudates on the photophysiology of the green alga Scenedesmus quadricauda by chlorophyll fluorescence analysis. We were able to prove the effect of algal cell-free filtrates on the performance of S. quadricauda and demonstrate for the first time that the freshwater picocyanobacterium Cyanobium gracile has strong negative impact on the coexisting green alga. Neither the cyanotoxin (MYC, CYN and ATX) producing, nor the non-toxic strains showed any systematic effect on the production of S. quadricauda. Various strains of the cyanobacterium Cylindrospermopsis raciborskii inhibited the performance of the green alga independently of their origin. Our results urge further studies for a better understanding of the factors affecting the release of allelopathic compounds and the mechanisms of their effects on target organisms.

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Vizsgálatunkban 480 önként jelentkező középiskolás tanuló (n = 476; 224 fiú, 252 lány; kor: 12-18 év, átlagban 15,97 ±1,25 év; 139 budapesti; 234 vidéki kisvárosi; 103 falun élő) vett részt. A vizsgálati személyek szorongásszintje (rövidített CPI kérdőív) eltért nemek szerint (kétmintás t -próba; p <0,01), és korcsoportok szerint (egyirányú ANOVA; p <0,05), a lakóhely alapján azonban nem (egyirányú ANOVA). A szorongásszintet szignifikánsan befolyásolta a közeli rokonok és a barátok száma (egyirányú ANOVA; p <0,05; p <0,01 ); a mobiltelefon-beszélgetés gyakorisága a családdal, a barátokkal és az ismerősökkel (egyirányú ANOVA; p <0,05); az SMS-küldés gyakorisága a barátoknak és az ismerősöknek (egyirányú ANOVA; p <0,05), valamint az ismerkedésre való képesség és az ismeretlenekkel vagy kevéssé ismertekkel szembeni bizalom (egyirányú ANOVA; p <0,01). Adataink alapján úgy tűnik, hogy a szorongási szint csökkentésében a kapcsolati háló potenciális új tagjai felé irányuló kezdeményezőkészség és bizalom mellett elsősorban a közepes erősségű kapcsolatok száma (közeli rokonok, barátok) és a közepes erősségű kommunikációs csatornák használati gyakorisága (mobiltelefon-beszélgetés, SMS) a jelentős tényezők. Az erős (családtag) és a nagyon gyenge (távoli rokon, ismerős) kapcsolatok száma, illetve az ezeknek megfelelő erős (személyes együttlét) vagy nagyon gyenge (anonim internetes kommunikáció) kommunikációs csatornák használatának mennyisége eredményeink szerint kisebb hatással van a szorongás alakulására.

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Solid phase microextraction (SPME) coupled to fast capillary gas chromatography was used for monitoring the wine fermentation process. This combination offers a simple, quick and sensitive approach suitable for characterization of head-space components of wines during the fermentation process without a complicated sample preparation procedure. In this work this method was used to observe the differences in aroma production between three different commercial yeasts and the indigenous yeast flora.

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Abstract

The Mid-Hungarian (or Zagreb-Zemplin) Line of WSW-ENE strike divides the Pannonian basement into two mega-units, the Tisia Composite Terrane in the SE and the ALCAPA Composite Terrane in the NW. They became juxtaposed no earlier than the Middle Miocene (Karpathian). Their present adjacent zones show very different Variscan and Alpine evolution and relationships, which are briefly reviewed here and confronted in the light of detailed correlational work published during the last decade. The present contribution summarizes Variscan and Alpine evolution of units/terranes juxtaposed along the Mid-Hungarian Line, the major terrane boundary in the pre-Neogene basement of the Pannonian Basin, as can be seen on the Circum-Pannonian terrane maps.

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Rendszeresen alkoholt fogyasztó, 38 éves férfinél a súlyos, vashiányos anaemia hátterében aranyeres vérzést találtak. Parenteralis vaspótlás ellenére ismételten anaemizálódott, majd romló általános állapot és mélyülő icterus miatt került sor intézeti felvételére. Az elvégzett laboratóriumi vizsgálat során 38 g/l-es hemoglobinérték, súlyos vashiány és májcirrhosis igazolódott, amelynek hátterében a toxikus károsodáson kívül más okot ki lehetett zárni. Életmódváltás, gyógyszeres kezelés, a proktológiai beavatkozások és a szigorú követés hatására állapotában gyors javulás lépett fel, majd a per rectim vérzések is megszűntek. A májzsugor súlyos szövődménye, a gastrointestinalis vérzés leggyakrabban a felső gyomor-bél traktusból származik. Ritka az alsó traktusból, azon belül az aranyerekből történő vérzés ebben a betegségben, amely – mint a szerzők esetében is – életet veszélyeztető vérvesztést is okozhat. Kezelésére eredményes módszer a más, invazív beavatkozásokhoz képest kevesebb szövődménnyel és kisebb fájdalommal járó sclerotherapia. Cirrhosis hepatis aranyérrel való társulása esetén is elmondható, hogy a kezelés hosszú távú eredményességét döntően befolyásolja a beteg megfelelő együttműködési készsége. Orv. Hetil., 2013, 154, 382–386.

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It is known that bacterial lipopolysaccharide (LPS) is not absorbed from the gastrointestinal tract in significant quantities. However, the question remained whether oral LPS modified the structure or function of the gut. In the present experiment Escherichia coli O83 LPS was administered to growing rats in repeated oral doses of 400 mg/kg body weight (b. w.), every 8 h. After three days of treatment, morphometric and histochemical examinations of the small intestine did not show significant differences between treated and control rats. It is concluded that repeated oral administration of high doses of E. coli O83 LPS had no demonstrable effect on intestinal structure and cell proliferation in a rat model.

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Many halophytes and halophilic microorganisms are capable to adapt to the extremities of saline habitats. This study reveals the taxonomic diversity and ecological tolerance of bacteria isolated from the rhizosphere of three different halophytes (Bolboschoenus maritimus, Puccinellia limosa and Aster tripolium) living in the vicinity of Kiskunság soda ponds. Following a sampling in September 2013, altogether 76 bacterial strains were isolated using two different media. The strains were identified on the basis of 16S rRNA gene sequencing following ARDRA grouping. Salt and pH tolerance of the strains were examined by measuring their growth in broths containing 0–15% NaCl (w/V) and characterized with pH 7–12 values. Among the strains genera of Anaerobacillus, Bacillus and Exiguobacterium (Firmicutes), Agromyces, Isoptericola, Microbacterium, Micrococcus, Nocardiopsis, Nesterenkonia and Streptomyces (Actinobacteria), Halomonas and Idiomarina (Proteobacteria) and Anditalea (Bacteroidetes) were identified. The Bolboschoenus and Puccinellia samples characterized with the highest pH and electric conductivity values were dominated by Bacillus, Halomonas and Nesterenkonia, respectively. The salt tolerance of the bacterial strains was strongly dependent on the sampling location and plant species. In contrast, growth of bacterial strains in broths with alkaline pH values was more balanced. The strains from the Puccinellia sample showed the widest salt and pH tolerance.

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A preliminary study was conducted to compare the community level physiological profile (CLPP) and genetic diversity of rhizosphere microbial communities of four plant species growing nearby Kiskunság soda ponds, namely Böddi-szék, Kelemen-szék and Zab-szék. CLPP was assessed by MicroResp method using 15 different substrates while Denaturing Gradient Gel Electrophoresis (DGGE) was used to analyse genetic diversity of bacterial communities. The soil physical and chemical properties were quite different at the three sampling sites. Multivariate statistics (PCA and UPGMA) revealed that Zab-szék samples could be separated according to their genetic profile from the two others which might be attributed to the geographical location and perhaps the differences in soil physical properties. Böddi-szék samples could be separated from the two others considering the metabolic activity which could be explained by their high salt and low humus contents. The number of bands in DGGE gels was related to the metabolic activity, and positively correlated with soil humus content, but negatively with soil salt content. The main finding was that geographical location, soil physical and chemical properties and the type of vegetation were all important factors influencing the metabolic activity and genetic diversity of rhizosphere microbial communities.

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Karst areas belong to the most exposed terrestrial ecosystems, therefore their study have a priority task in Hungary, as well. The aim of this study was to compare the structure, activity and diversity of soil microbial communities from two distinct Hungarian karst areas (Aggtelek NP and Tapolca-basin). Soil samples were taken three times from 6 distinct sites, from different depths. Soil microbial biomass C (MBC), microbial biomass N (MBN), basal respiration (BRESP) and substrate induced respiration (SIR) were measured. The phylogenetic diversity of bacterial communities was compared by Denaturing Gradient Gel Electrophoresis (DGGE). The highest MBC, MBN, BRESP and SIR values were measured in the rendzina soil from Aggtelek. On the basis of biomass and respiration measurements, microbial communities differentiated mainly according to soil depths whereas DGGE profiles of bacterial communities resulted in groups mainly according to sampling sites.

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