38 results on '"Kupka, Daniel"'
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2. Kinetics study comparing bacterial growth and iron oxidation kinetics over a range of temperatures 5–45 °C
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Kupka, Daniel, Bártová, Zuzana, and Hagarová, Lenka
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- 2023
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3. Differences in metabolites production using the Biolog FF Microplate™ system with an emphasis on some organic acids of Aspergillus niger wild type strains
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Šimonovičová, Alexandra, Kupka, Daniel, Nosalj, Sanja, Kraková, Lucia, Drahovská, Hana, Bártová, Zuzana, Vojtková, Hana, Boturová, Kateřina, and Pangallo, Domenico
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- 2020
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4. Stereoselective synthesis and antiproliferative activity of the isomeric sphinganine analogues
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Čonková, Miroslava, Martinková, Miroslava, Gonda, Jozef, Jacková, Dominika, Pilátová, Martina Bago, Kupka, Daniel, and Jáger, Dávid
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- 2019
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5. Synthesis of the cytotoxic phytosphingosines and their isomeric analogues
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Raschmanová, Jana Špaková, Martinková, Miroslava, Gonda, Jozef, Pilátová, Martina Bago, Kupka, Daniel, and Jáger, Dávid
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- 2018
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6. Interkulturelle Kompetenz : eine Jahrhundertkompetenz
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Karabegovic, Azra, Schönbächler Marcar, Claudia, Kupka, Daniel, Domeisen Benedetti, Franzisca, Gisler, Livo, Kohler, Sara Kerstin, Schärli-Lim, Susan, Karabegovic, Azra, Schönbächler Marcar, Claudia, Kupka, Daniel, Domeisen Benedetti, Franzisca, Gisler, Livo, Kohler, Sara Kerstin, and Schärli-Lim, Susan
- Published
- 2023
7. Kinetics Study Comparing Bacterial Growth and Iron Oxidation Kinetics Over A Range of Temperatures 5-45 °C
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Bártová, Zuzana, primary, Kupka, Daniel, additional, and Hagarová, Lenka, additional
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- 2023
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8. Mitochondriale Effekte des Schwefelwasserstoffdonors AP39 auf Hepatozyten im Rahmen einer Lipopolysaccharid-Stimulation
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Kupka, Daniel, Calzia, Enrico, and Formentini, Andrea
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Cell respiration ,Endotoxins ,Hydrogen sulfide ,Endotoxin ,Mitochondriale Atmung ,Lipopolysaccharide ,ddc:610 ,Atmungskette ,Reactive oxygen species ,Schwefelwasserstoff ,DDC 610 / Medicine & health - Abstract
Schwefelwasserstoff (H2S) stellt neben Kohlenstoffmonoxid und Stickstoffmonoxid einen der drei wichtigsten Gasotransmitter des menschlichen Körpers dar. Trotz seiner Toxizität wird H2S endogen synthetisiert und vermittelt als Botenmolekül diverse physiologische Einflüsse. Das gasförmige H2S kann durch Diffusion und ohne den Einsatz von Transportern das Mitochondrium erreichen und benötigt als Energieträger keinerlei biochemischer Vorbereitung. Aus diesen Gründen ist der Gasotransmitter in den letzten Jahren zunehmend in den Fokus wissenschaftlicher Arbeiten geraten. Neben den antioxidativen sowie zytoprotektiven Effekten sind insbesondere Interaktionen von H2S mit der mitochondrialen Atmungskette beschrieben. In einem niedrigen Konzentrationsbereich dient H2S als zusätzlicher Elektronendonor. Durch das Einspeisen von Elektronen wird der Protonengradient, der zur letztendlichen Adenosintriphosphat-Gewinnung dient, weiter aufgebaut. In höheren Konzentrationen interagiert H2S mit der Cytochrom-c-Oxidase (COX) der Atmungskette. Durch die reversible Bindung wird die Fähigkeit zur Sauerstoffbindung gehemmt und der Elektronenfluss über die Atmungskette kommt zum Erliegen. In der vorliegenden Studie wurde zur exogenen H2S-Applikation das synthetische Molekül [(10-oxo-10-(4-(3-thioxo-3H-1,2-dithiol-5yl)phenoxy)decyl) Triphenyl Phosphonium Bromid] (AP39) verwendet. AP39 ist ein mitochondrial gerichteter H2S-Donor, welcher durch eine gezielte Freisetzung zu einer Akkumulation von H2S innerhalb der Mitochondrienmatrix führt. Aus diesem Grund ist es möglich die H2S-Konzentration zielgenauer zu titrieren und die effektive Dosis niedriger zu halten als diejenige von herkömmlichen Donoren. Um die Effekte der AP39- Stimulation (10 nM) zusätzlich im Rahmen eines akuten Inflammationsprozesses zu untersuchen, wurden die verwendeten Zellen mit Lipopolysacchariden (LPS, 1 µg/ml) behandelt. Ziel dieser Arbeit war die Veränderungen des mitochondrialen Sauerstoffverbrauchs, der Wasserstoffperoxid- (H2O2-) Produktion sowie der Proteinexpression zu untersuchen. Zur Messung des mitochondrialen Sauerstoffverbrauchs wurde eine hochauflösende Respirometrie durchgeführt. Für die simultane Messung der H2O2-Produktion wurde die Methode mit einer fluorometrischen Messung ergänzt. Die Bestimmung der Änderungen der Proteinexpression erfolgte durch Western Blots. Um die Effekte von AP39 besser nachvollziehen zu können, erfolgte in allen drei Methoden der Vergleich mit der jeweiligen Dimethylsulfoxid-Kontrollgruppe. Aus den Ergebnissen können folgende Schlussfolgerungen gezogen werden. Die Applikation von AP39 verursachte eine zeitabhängige Inhibition des mitochondrialen Sauerstoffverbrauchs. Diese Inhibition wurde im Rahmen eines akuten Inflammationsprozesses noch weiter verstärkt. Ursächlich dafür könnte die Akkumulation des H2S und die damit verbundene Inhibition der COX mit zunehmender Stimulationsdauer von AP39 sein. Die Durchführung des Cytochrom c-Tests legt die Vermutung nahe, dass die LPS-induzierte Inflammation zu einer mitochondrialen Dysfunktion führte, welche mit einer erhöhten Permeabilität sowie einem Verlust des Membranpotentials einherging. Die gleichzeitige Applikation von H2S konnte diese Tendenz nicht verhindern. Der erwartete zytoprotektive Effekt von AP39 im Rahmen einer Inflammation konnte nicht gezeigt werden. Die verwendete AP39-Konzentration sowie das genutzte Zeitfenster von zwei beziehungsweise 24 Stunden waren möglicherweise nicht optimal, um protektive Effekte von AP39 im Rahmen einer akuten Inflammation nachzuweisen. Nichtsdestotrotz ist das klinische Potenzial von H2S sehr vielversprechend. Der Einsatz wird aktuell aufgrund der unselektiven Applikationsmöglichkeiten und der daraus resultierenden geringen therapeutischen Breite nicht praktiziert. Eine Inhibition des Sauerstoffverbrauchs durch AP39 könnte sich insbesondere im Rahmen einer akuten Inflammation, welche in einer Dysbalance von Sauerstoffangebot und -bedarf mündet, günstig auswirken. Dieser Aspekt könnte den speziell mitochondriengerichteten H2S-Donor AP39 in Zukunft zu einem wichtigen Teil des Therapiekonzepts bei der Behandlung inflammatorischer Krankheitsbilder machen.
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- 2022
9. Wird kognitive Leistung durch die Vitamin D-Konzentration beeinflusst? Eine Betrachtung bei Überwinterern in der Antarktis
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Kupka, Daniel Wilhelm
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vitamin D deficiency ,Antarctica ,vitamin d ,extreme environments ,cognitive decline ,cognitive performance ,600 Technik, Medizin, angewandte Wissenschaften::610 Medizin und Gesundheit::610 Medizin und Gesundheit - Abstract
Einleitung: Langzeitaufenthalte in extremen Umwelten wie der Antarktis sind mit verschiedenen Herausforderungen an den menschlichen Körper verbunden. Unter anderem verringert sich die Vitamin D-Produktion in der Haut durch das deutlich verminderte Sonnenlicht. Auswirkungen von Vitamin D-Mangel auf den Knochenstoffwechsel sind seit vielen Jahren anerkannt. In den letzten Jahrzehnten wurde Vitamin D zudem in Zusammenhang mit dem zentralen Nervensystem gebracht. Der Vitamin D-Rezeptor und die Vitamin D-Metaboliten wurden im Gehirn nachgewiesen und strukturelle Veränderungen des Gehirns sind mit Vitamin D assoziiert. Vitamin D soll auch neurotroph und neuroprotektiv wirken. Beobachtungsstudien haben auf einen Zusammenhang zwischen niedriger Vitamin D-Konzentration und kognitiver Dysfunktion bzw. Demenz hingewiesen. Interventionsstudien konnten dies jedoch nicht hinreichend bestätigen. Das Ziel der Studie ist es, den Einfluss der Vitamin D-Konzentration auf die kognitive Leistungsfähigkeit während eines Langzeitaufenthalts in der Antarktis zu untersuchen. Methodik: Langzeitüberwinterer hielten sich im Rahmen von drei Überwinterungskampagnen (33.–35.) für 14 Monate auf der deutschen Neumayer-Station III in der Antarktis auf. Studienteilnehmer (n = 9 pro Kampagne) waren die Antarktis-Forscher des Alfred-Wegener-Instituts. Die Vitamin D-Konzentration und die kognitive Leistungsfähigkeit wurden monatlich vor, während und nach der Überwinterung gemessen. Die kognitive Leistungsfähigkeit wurde mittels validierter computerbasierter Testbatterien (ANAM4TM oder Cognition) ermittelt. Die untersuchten Leistungsparameter waren die Effizienz und die Reaktionszeit. Die Datenanalyse erfolgte mithilfe eines linear gemischten Modells. Es wurde für Alter und Geschlecht kontrolliert. Ergebnisse: Die Vitamin D-Konzentration nahm während der Überwinterung bei allen Kampagnen signifikant ab und erholte sich zur Nachmessung nur bei den Teilnehmern der 33. und 34. Überwinterungskampagne im Vergleich zur Vormessung. Über die Zeit zeigte sich eine signifikante Verbesserung der Effizienz und der Reaktionszeit bei 9 bzw. 10 der 10 kognitiven Tests in der ANAM4TM-Batterie und bei 6 bzw. 8 der 10 kognitiven Tests in der Cognition-Batterie. Bei höherer Vitamin D-Konzentration verschlechterten sich die Effizienz und die Reaktionszeit signifikant bei 9 bzw. 10 Tests in der ANAM4TM-Batterie und bei 2 bzw. 4 Tests in der Cognition-Batterie. Schlussfolgerung: Die Verbesserung der kognitiven Leistungsfähigkeit über die Zeit beruht vermutlich auf einen Lerneffekt. Der signifikante negative Zusammenhang zwischen der Vitamin D-Konzentration und der kognitiven Leistungsfähigkeit bei den Langzeitüberwinterern in der Antarktis ist deshalb mit Vorsicht zu betrachten. Weitere Studien sind notwendig, um die Einflüsse von Vitamin D auf das Gehirn und die kognitive Leistungsfähigkeit zu klären., Introduction: Humans face different challenges during extended stays in extreme environments such as Antarctica. Among these challenges is the reduced solar radiation which results in less cutaneous vitamin D synthesis. The effects of vitamin D deficiency on skeletal diseases have been well established. During the past decades, vitamin D has been linked to the central nervous system, as the vitamin D Receptor and metabolites have been located in the brain and as vitamin D has been shown to have neurotrophic and neuroprotective effects. Previous research has also established correlations between vitamin D and structural alterations in the brain. Moreover, observational studies support a correlation between low vitamin D levels and cognitive decline and dementia, respectively. However, interventional studies fail to show this association. The aim of this study is to investigate the impact of vitamin D levels on cognitive performance during an extended stay in Antarctica. Methods: As part of three winter campaigns (33rd-35th), people were overwintering for a duration of 14 months per campaign at the Antarctic German research station Neumayer III. The participants were Antarctic scientists recruited by the Alfred Wegener Institute (n = 9 per campaign). Vitamin D levels and cognitive performance were measured before and after the expedition as well as monthly during their stay. Cognitive performance was determined by validated computerized test batteries (ANAM4TM or Cognition). The performance parameters efficiency and reaction time were evaluated. A linear mixed model was used for statistical analysis, while controlling for the effects of age and gender. Results: Vitamin D levels significantly decreased in all campaigns during overwintering and only for the 33rd and 34th campaign did they recover to the same levels after their return home. Over time, efficiency and reaction time showed significant improvement in 9 and 10 of the 10 ANAM4TM battery cognitive tests, respectively, as well as in 6 and 8 of the 10 Cognition battery cognitive tests, respectively. With high vitamin D levels, efficiency and reaction time worsened significantly in 9 and 10 of the ANAM4TM battery tests, respectively, as well as in 2 and 4 of the Cognition battery tests, respectively. Conclusion: The cognitive improvement over time is presumably caused by practice effects. The significant negative association between vitamin D levels and cognitive performance in the sample should therefore be interpreted with caution. More studies are needed to assess the impact of vitamin D on cognitive performance and the brain.
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- 2022
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10. Characterization of polymetallic ore and flotation concentrate from the Mária Mine (Rožňava, Špis-Gemer Ore Mts., Eastern Slovakia)
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Hredzák, Slavomír, primary, Matik, Marek, additional, šestinová, Olga, additional, Kupka, Daniel, additional, Hančul’ák, Jozef, additional, Zubrik, Anton, additional, Znamenácková, Ingrid, additional, Dolinská, Silvia, additional, Sisol, Martin, additional, and Marcin, Michal, additional
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- 2021
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11. Synthesis of Novel Biologically Active Proflavine Ureas Designed on the Basis of Predicted Entropy Changes
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Janovec, Ladislav, primary, Kovacova, Eva, additional, Semelakova, Martina, additional, Kvakova, Monika, additional, Kupka, Daniel, additional, Jager, David, additional, and Kozurkova, Maria, additional
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- 2021
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12. The Environment Specialities in the Ochtinska Aragonite Cave
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Bobro Milan, Hanèu¾ák Jozef, and Kupka Daniel
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carbon dioxide ,cave ,concentration ,incrustation effect of water ,residual ochre loams ,Mining engineering. Metallurgy ,TN1-997 ,Geology ,QE1-996.5 - Abstract
The Ochtinska Aragonite Cave became well-known due to its unique decoration created by fruticose-like aggregates of crystalline aragonite. The cave is located in the cadastral territory of the village of Ochtiná on the west side of the Hrádok Mt. that belongs to the Slovenské Rudohorie Mts. During the opening season the cave is frequented. In the last period, an increased amount of CO2 has been detected in air of the Ochtinska aragonite cave. The cave environment is created by caverns - relicts after mouldered ankerites and siderites in surroundings of Palaeozoic slates, limestones and dolomites. The residual ochre loams were created by weathering of carbonates. Probably, these processes held up till now and this fact may also result in the liberation of CO2. From the viewpoint of the enhanced CO2 content, the earths and waters occurred in the cave were found as its possible source. An enhanced CO2 content was also measured in old air-proof closed mine workings, with a possibility of rot processes of old organic mine working components. Probably, has the rich attendance of the cave during the season the highest influence on the enhanced CO2 content. The measurements of CO2 content have pointed to its different values in various periods. In the period without visits, the CO2 content in the cave exceeds that in the external surrounding air by 3-4 times, i. e. 310 330 ppm. In the period of visits, it is 8 10 times. Thus, the CO2 content in the cave depends on the number of visits. Up till now, no influence of the CO2 content variation on the unique karstic forms and the health status of the cave staff was not proven.
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- 2003
13. A complementary study of hydrophobicity and surface charge of Thiobacillus ferrooxidans. The effect of ionic surfactants
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Turèániová ¼udmila, Kupka Daniel, and kvarla Jiøí
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Thiobacillus ferrooxidans ,hydrophobicity ,CTAB ,BATH ,electrophoretic ,zeta ,Mining engineering. Metallurgy ,TN1-997 ,Geology ,QE1-996.5 - Abstract
Hydrofóbnos a náboj buneènej steny sú rozhodujúce faktory poèiatoèného tádia adhézie baktérií na tuhé povrchy. Hydrofóbnos bakteriálnych buniek sa posudzuje najmä dvoma spôsobmi. Ako prvý spôsob, umoòujúci kvalitatívne urèenie hydrofóbnosti, sa vyuíva sledovanie adsorpcie iónogénnych surfaktantov, resp. elektroforetickej pohyblivosti ktorá ju sprevádza. Druhým spôsobom semikvan-titatívneho stanovenia hydrofóbnosti buniek je testovanie ich interakcie s kvapalnými uh¾ovodíkmi v tzv. BATH teste (Bacterial Adhesion To Hydrocarbons). Stanovenie hydrofóbnosti pouitím BATH testu je vak komplikované z dôvodu spolupôsobenia elektrostatickej interakcie, ktorú môme opä odhadnú z elektroforetickej pohyblivosti buniek.Cie¾om práce bolo posúdi hydrofóbnos buniek Thiobacillus ferrooxidans oboma uvedenými spôsobmi zvlá a v kombinácii, tj. BATH test bol uskutoènený v prítomnosti surfaktantov a súèasne bola meraná elektroforetická pohyblivos buniek metódou ELS (Electrophoretic Light Scattering). V neprítomnosti surfaktantov bola zistená záporná elektroforetická pohyblivos (náboj) a silná hydro-filnos povrchu baktérií. V prítomnosti katiónaktívneho surfaktantu (CTAB) sa v dôsledku jeho postupnej adsorpcie elektroforetická pohyblivos zniovala (dokonca pri vysokých koncentráciách prechádzala do kladných hodnôt). Súèasne sa indukovala hydrofóbnos buniek. Po prekroèení urèitej CTAB koncentrácie sa vak hydrofóbnos zaèala zniova, hoci elektroforetická pohyblivos bola stále na zostupe (èo svedèí o neustávajúcom raste adsorpcie CTAB). To svedèí o adsorpcii CTAB katiónov s polárnymi skupinami orientovanými smerom k povrchu buniek a hydrofóbnymi reazcami smerom do roztoku pri nízkych koncentráciách CTAB a o opaènej orientácii pri vyej koncentrácii CTAB. Po pridaní aniónaktívneho surfaktantu (SDS) k adsorpcii nedolo, o èom svedèí iba mierne zvýenie zápornej elektroforetickej pohyblivosti a skoro vôbec neovplyvnená pôvodná hydrofilnos buniek.Na základe toho môme predpoklada, e elektrostatické interakcie ovplyvòujú hydrofilnos/hydrofóbnos buniek T. ferrooxidans BATH testom iba v malej miere.
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- 2002
14. Charge and softness of the outer part of the cell wall of Thiobacillus ferrooxidans in the low ionic strength medium
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Škvarla Jiří and Kupka Daniel
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zeta potential ,surface electric charge ,electrophoretic mobility ,microbial cells ,soft cell analysis ,Thiobacillus ferrooxidans ,Mining engineering. Metallurgy ,TN1-997 ,Geology ,QE1-996.5 - Abstract
The surface charge and surface potential are parameters influencing the microbial adhesion phenomenon through the electrostatic interaction between bacteria and substrates. The Smoluchowski equation, originally developed for estimating the above parameters from the experimentally accessible electrophoretic mobility of rigid colloid particles, is however inapplicable to the elastic bacterial cells. The problem is that the outer cell wall of bacteria is a layer with a complex polyelectrolyte structure. In this article, the OhshimaLs model of the gsofth particle is applied to describe the surface electrostatics of Thiobacillus ferrooxidans cells by measuring their electrophoretic mobility in distilled water as a function of a (low) ionic strength and pH. In this model, the rigid core is considered to be covered with a charged ion-penetrable layer of polyelectrolytes. Two model parameters have been determined by the curve fitting at pH from 3.2 to 5.8, namely the number density of the dissociated groups N and the softness parameter 1/É of the polyelectrolyte layer of the bacterium. A disagreement of the best fit parameters (evaluated by the correlation coefficient) with the analogous parameters determined for other colloids (including bacterial cells) in aqueous solutions of a high ionic strength is discussed.
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- 2002
15. The role of surface properties of Thiobacillus Ferrooxidans and minerals in microbial adhesion
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Kupka Daniel, Grohol Milan, and Jiøí kvarla
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Thiobacillus ferrooxidans ,pyrite ,adhesion ,zeta potential ,TLW method ,Mining engineering. Metallurgy ,TN1-997 ,Geology ,QE1-996.5 - Abstract
To explain the selective microbial adhesion of Thiobacillus ferrooxidans on pyrite, zeta potential of both the bacterium cells and the mineral was measured using the electrophoretic light scattering (ELS) technique. Simultaneously, relative hydrophobicity of the cells and the mineral was determined by the liquid-liquid partition (BATH) test and the thin-layer wicking method (TLW), respectively. Heteroaggregation of the cells with the pyrite particles has been evaluated qualitatively from the ELS spectra provided by their mixtures at different pH and interpreted in terms of the Lifshitz-van der Waals and acid-base surface thermodynamics model of microbial adhesion
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- 2001
16. Oxidation of elemental sulfur, tetrathionate and ferrous iron by the psychrotolerant Acidithiobacillus strain SS3
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Kupka, Daniel, Liljeqvist, Maria, Nurmi, Pauliina, Puhakka, Jaakko A., Tuovinen, Olli H., and Dopson, Mark
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- 2009
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17. Petrographical and mineralogical analysis of coal after biological leaching
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Kupka Daniel, Èurillová Dana, Sýkorová Ivana, and Machajová Zlatica
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Thiobacillus ferrooxidans ,petrographical and mineralogical analysis. ,Mining engineering. Metallurgy ,TN1-997 ,Geology ,QE1-996.5 - Abstract
For coal utilization the sulphur content is a decisive parameter for the quality of the coal. In many countries clean coal technologies have to be applied on the basis of regulations concerning fuel quality and emission standards for dust, CO, SO2 and NOx in the flue gas. It becomes quite obvious that it is always preferable to keep the sulphur levels in coal at a minimum. Bacterial oxidation of the sulphur present in coal could well be thought of as an effective alternative.Desulphurization by bacteria Thiobacillus ferrooxidans was applied to coal sample from Sokolov mine. Bacteria growing in batch culture on ferrous iron at initial pH 1.6 were harvested at the later growth phase. The ferric iron precipitates were separated from the cells by centrifugation and the rest medium by membrane filtration. Cell pellet captured on the filter was washed by hydrochloric acid and distilled water and finally suspended in fresh Waksmann & Joffe medium. The medium was previously acidified by 5M H2SO4 to pH 2. Initial concentration of sulphates in medium was 1.8 g L-1. Desulphurization of coal was studied in a stirred batch reactor at 10% w/v pulp density in diluted H2SO4 at pH = 2.The effect of bacterial leaching on mineral and organic matter of coal was followed by optical microscopy. Petrographic evaluation of the coal matter samples consisted of the determination of reflectance of gelified huminite macerals (R0), determination of maceral group contents of huminite, liptinite, inertinite and determination of the mineral content with emphasis on the various forms of iron sulphides. The sample examined were brown coal with higher liptinite and pyrite contents. The huminite reflectance of 0,33 % is corresponding to the lignitic metatype. Huminite concentration is 65,7 % and is the most abundant maceral group. The maceral ulminite and densinite contributes to the high huminite content. The concentration of attrinite, who be pass to liptodetrinite, textinite, gelinite and corpohuminite contents does not exceed 5 %. The maceral composition of liptinite was determined by a fluorescence measurement. The remaining liptinite macerals, i.e. liptodetrinite and bituminite, resinite, cutinite and fluorinite are accessories. The content of inertinite (fusinite, sklerotinite and inertodetrinite) is low (4,5 %).Coal contains sulphur in inorganic form (mainly pyrite and marcasite) and sulphur in organic form. Biological lixiviation has caused relatively significant change in FeS2, in some cases full or part elimination of dispersed framboids at mineralised detrite as well as at huminite macerals resulting in empty holes and hudge FeS2 grains were slightly disintegrated at the surface or dike - pyrite was relased irregularly after lixiviation.
- Published
- 2000
18. Recent knowledge about the role of bacterial adhesion in coal preparation
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Turèániová ¼udmila, Kupka Daniel, and kvarla Jiøí
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microbial adhesion ,surface properties ,Thiobacillus ferrooxidans ,Mining engineering. Metallurgy ,TN1-997 ,Geology ,QE1-996.5 - Abstract
V nadväznosti na flotáciu pyritu v uhlí sú zhrnuté súèasné poznatky o vplyve fyzikálno-chemických vlastností buneènej steny baktérie Thiobacillus ferrooxidans na jej adhéziu na povrch rôznych minerálov a uhlia. Aplikovaním modelu mikrobiálnej adhézie (kvarla, J. Chem. Soc. Faraday Trans., 89, 1993, p. 2913-2921) a vyuitím známych parametrov vstupujúcich do tohoto modelu bolo zistené, e k (reverzibilnej) adhézii T. ferrooxidans dochádza spravidla v sekundárnom minime. Pre posúdenie monosti vyuitia tohoto modelu na objasnenie selektívneho prichytenia T. ferrooxidans na pyrit je vak potrebné doplni chýbajúce údaje vstupujúce do tohoto modelu.
- Published
- 1998
19. Microbial degradation of petroleum hydrocarbons in soil
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Kupka Daniel
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petroleum hydrocarbons biodegradation ,soil bioremediation. ,Mining engineering. Metallurgy ,TN1-997 ,Geology ,QE1-996.5 - Abstract
The abilities of microorganisms to mineralize a wide range of pollutants are well known. Biological processes for the removal of crude oil hydrocarbons from environment are attractive because they consume less energy than conventional physico-chemical processes and offer possibilities for recycling chemicals in the framework of integrated system.
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- 1997
20. Removal of Contaminants from Water by Bacterial Activity
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JENČÁROVÁ, Jana, primary, LUPTÁKOVÁ, Alena, additional, and KUPKA, Daniel, additional
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- 2020
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21. Deferrization of Kaolinic Sand by Iron Oxidizing and Iron Reducing Bacteria
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Kupka, Daniel, primary, Lovás, Michal, additional, and Šepelák, Vladimir, additional
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- 2007
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22. Reduction of Soluble and Solid Ferric Iron by Acidiphilium SJH
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Vašková, Alexandra, primary and Kupka, Daniel, additional
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- 2007
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23. Sulfur Oxidation and Coupled Iron Reduction at Low Temperatures
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Kupka, Daniel, primary, Dopson, Mark, additional, and Tuovinen, Olli H., additional
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- 2007
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24. Iron Oxidation and Bioleaching Potential at Low Temperatures
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Dopson, Mark, primary, Kupka, Daniel, additional, Halinen, Anna Kaisa, additional, Rahunen, Nelli, additional, Özkaya, Bestamin, additional, Sahinkaya, Erkan, additional, Rzhepishevska, Olena I., additional, Kaksonen, Anna H., additional, Karnachuk, Olia V., additional, Tuovinen, Olli H., additional, and Puhakka, Jaakko A., additional
- Published
- 2007
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25. A comparative electrophoretic light scattering study of various strains of Thiobacillus ferrooxidans
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Škvarla, Jiří and Kupka, Daniel
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- 1996
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26. Mineralogy and geochemistry of the copper-dominated neutral mine drainage at the Cu deposit Ľubietová-Podlipa (Slovakia)
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Majzlan, Juraj, primary, Števko, Martin, additional, Chovan, Martin, additional, Luptáková, Jarmila, additional, Milovská, Stanislava, additional, Milovský, Rastislav, additional, Jeleň, Stanislav, additional, Sýkorová, Martina, additional, Pollok, Kilian, additional, Göttlicher, Jörg, additional, and Kupka, Daniel, additional
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- 2018
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27. Elimination of 2-chlorophenol by two types of iron particles
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Sekula, Peter, primary, Bačik, Miroslav, additional, Mosej, Juraj, additional, Sekula, Peter, additional, Berillo, Dmitriy, additional, Zeng, Yishan, additional, Kupka, Daniel, additional, Václavíková, Miroslava, additional, and Ivaničová, Lucia, additional
- Published
- 2018
- Full Text
- View/download PDF
28. Degradation of Reactive Black 5 by electrochemical oxidation
- Author
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Jager, David, primary, Kupka, Daniel, additional, Vaclavikova, Miroslava, additional, Ivanicova, Lucia, additional, and Gallios, George, additional
- Published
- 2018
- Full Text
- View/download PDF
29. User support 4ft-Miner procedure for data mining
- Author
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Kupka, Daniel, Rauch, Jan, and Ralbovský, Martin
- Abstract
Up to now the file of knowledges with 4ft-Miner procedure was concerned only in the heads of data mining analysts. So, it was usefull, pursuant many analyses, to collect advices and experiences for data mining. This file of advices is also a part of this work. Furthermore, theoretical findings about using applicable 4ft-quantifiers according to practical situation are presented. This work also contains proposal of two new 4ft-quantifiers - above negation quantifier and pairing quantifier. For ASSOC-procedures users web application for collecting, editing advices, experiences and background knowledges is discribed and implemented. Benefit of this application is also in structuralization of inserted informations. The work also contains common design and the description of implementation of the tool for advices creation in Ferda DataMiner environement. Here, proceeding from possibilities ordered by their priority can be choosen. Informations provided by this tool are not only static, but they react on results of present and last analyses.
- Published
- 2007
30. Les pratiques de valorisation de la recherche publique : un éclairage international
- Author
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Cervantes, Mario, primary, Guellec, Dominique, additional, and Kupka, Daniel, additional
- Published
- 2014
- Full Text
- View/download PDF
31. Fracture experiments of single grain boundaries in ductile metals
- Author
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Huber, Norbert, Kupka, Daniel, Huber, Norbert, and Kupka, Daniel
- Abstract
Eine Methode, zur Untersuchung des Bruches einzelner Korngrenzen in duktilen Metallen, wurde auf Basis von Biegeversuchen an Mikro-Balken entwickelt. Die plastische Deformation der Biegebalken wurde mittels eines Finite Elemente Kristallplastizitätsmodells vorhergesagt, welches mit Hilfe von Druckversuchen an einkristallinen Mikrosäulen kalibriert wurde. Die Bruchparameter der Korngrenzen wurden dann im Rahmen eines Kohäsivzonenmodells bestimmt., A method to investigate the fracture of a single grain boundary in ductile metals is developed based on micro-cantilever bending experiments. The plastic deformation of the cantilevers is predicted by a finite element crystal plasticity model which is calibrated making use of micro-compression experiments on single crystalline micro columns. The fracture parameters of a grain boundary are then determined in terms of a cohesive zone model.
- Published
- 2013
32. Bacterial oxidation of ferrous iron at low temperatures.
- Author
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Kupka, Daniel, Rzhepishevska, Olena, Dopson, Mark, Lindström, Börje, Karnachuk, Olia V, Tuovinen, Olli H, Kupka, Daniel, Rzhepishevska, Olena, Dopson, Mark, Lindström, Börje, Karnachuk, Olia V, and Tuovinen, Olli H
- Abstract
This study comprises the first report of ferrous iron oxidation by psychrotolerant, acidophilic iron-oxidizing bacteria capable of growing at 5 degrees C. Samples of mine drainage-impacted surface soils and sediments from the Norilsk mining region (Taimyr, Siberia) and Kristineberg (Skellefte district, Sweden) were inoculated into acidic ferrous sulfate media and incubated at 5 degrees C. Iron oxidation was preceded by an approximately 3-month lag period that was reduced in subsequent cultures. Three enrichment cultures were chosen for further work and one culture designated as isolate SS3 was purified by colony isolation from a Norilsk enrichment culture for determining the kinetics of iron oxidation. The 16S rRNA based phylogeny of SS3 and two other psychrotolerant cultures, SS5 from Norilsk and SK5 from Northern Sweden, was determined. Comparative analysis of amplified 16S rRNA gene sequences showed that the psychrotolerant cultures aligned within Acidithiobacillus ferrooxidans. The rate constant of iron oxidation by growing cultures of SS3 was in the range of 0.0162-0.0104 h(-1) depending on the initial pH. The oxidation kinetics followed an exponential pattern, consistent with a first order rate expression. Parallel iron oxidation by a mesophilic reference culture of Acidithiobacillus ferrooxidans was extremely slow and linear. Precipitates harvested from the 5 degrees C culture were identified by X-ray diffraction as mixtures of schwertmannite (ideal formula Fe(8)O(8)(OH)(6)SO(4)) and jarosite (KFe(3)(SO(4))(2)(OH)(6)). Jarosite was much more dominant in precipitates produced at 30 degrees C. (c) 2007 Wiley Periodicals, Inc.
- Published
- 2007
- Full Text
- View/download PDF
33. Iron oxidation and bioleaching potential at low temperatures
- Author
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Dopson, Mark, Kupka, Daniel, Halinen, Anna-Kaisa, Rahunen, Nelli, Özkaya, Bestamin, Sahinkaya, Erkan, Rzhepishevska, Olena I, Kaksonen, Anna H, Karnachuk, Olia V, Tuovinen, IH, Puhakka, Jaakko A, Dopson, Mark, Kupka, Daniel, Halinen, Anna-Kaisa, Rahunen, Nelli, Özkaya, Bestamin, Sahinkaya, Erkan, Rzhepishevska, Olena I, Kaksonen, Anna H, Karnachuk, Olia V, Tuovinen, IH, and Puhakka, Jaakko A
- Published
- 2007
- Full Text
- View/download PDF
34. Secondary Iron Minerals Present in AMD Sediments from Smolník Abandoned Mine
- Author
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Dakos, Zuzana, primary, Kupka, Daniel, additional, Kovařík, Michal, additional, Jablonovská, Katarína, additional, Krištúfek, Václav, additional, and Achimovičová, Marcela, additional
- Published
- 2012
- Full Text
- View/download PDF
35. COMPARING OF SULPHATES REMOVING FROM REAL MINE WATER AND MODEL SOLUTION USING BARIUM SALTS.
- Author
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Špaldon, Tomislav, Kupka, Daniel, Hančuľák, Jozef, Šestinová, Oľga, and Findoráková, Lenka
- Subjects
- *
MINING research , *PYRITES , *WATER quality , *SULFATE minerals , *BARIUM salts - Abstract
Smolnik is mining area in Slovakia with very serious impact of mining activities on environment. The mine is known from 13th century by producing of cooper, iron, silver and gold. Mine was closed in 90s of the 20th century. More than 6 milion ton of pyrite ores of various qualities have been abandoned in the mine. The water quality of the Smolnik stream dramatically decreased a short time after the closing of the mine. Smolnik stream is classified as one of more contaminated in Slovakia, especially in sulphates amount and pH values. This is the reason for searching this problem. It is common knowledge that Barium is suitable reagent for sulphate reducing. The paper deals with sulphates removing from model solution using BaCO3 and Ba(OH)2 at various pH values and also sulphates removing from real mine water from old mine Smolnik using the same Ba reagents. Summary of paper describes optimal value pH value and optimal amount of Ba reagent per 1 liter and duration of interaction reagent with water for reaching allowable values of sulphates in the water. [ABSTRACT FROM AUTHOR]
- Published
- 2014
36. Bacterial oxidation of ferrous iron at low temperatures
- Author
-
Kupka, Daniel, primary, Rzhepishevska, Olena I., additional, Dopson, Mark, additional, Lindström, E. Börje, additional, Karnachuk, Olia V., additional, and Tuovinen, Olli H., additional
- Published
- 2007
- Full Text
- View/download PDF
37. Untitled.
- Author
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Šimonovičová, Alexandra, Kupka, Daniel, Nosalj, Sanja, Kraková, Lucia, Drahovská, Hana, Bártová, Zuzana, Vojtková, Hana, Boturová, Kateřina, and Pangallo, Domenico
- Abstract
This paper investigates the differences in some metabolites using Biolog FF Microplate™ system and the production of organic acids such as β-hydroxybutyric, p-hydroxyphenylacetic, and others. Another group of organic acids such as gluconic, oxalic and citric acid were studied during cultivation in a liquid medium. Four different Aspergillus niger (An) wild type strains were used as a model organism. Three strains, from the Banská Štiavnica – Šobov (An – Š), Pezinok (An – P) and Slovinky (An – Sl) localities were isolated from contaminated old mining areas with soil with ultra acidic to strong alkaline reactions. The fourth strain isolated from the Gabčíkovovo (An – G) locality was used for comparative purposes. According to the RAMP analysis, the strains are clustered into two groups, An – Š and An – P (similarity 82%), An – G and An – Sl (similarity 64%) which correlates with the pH values of the original environment. However, significant differences were found in metabolic processes in the reaction with a wide range of organic acids. In general, the reactions with D-lactic acid and D-malic acid correlate with the results of the RAMP analysis of fungal genotype similarities, the An – Š and An – P strains had an identical negative reaction, and an identical positive reaction was found in the An – Sl and An – G strains. During incubation the wild-type strains produced substantial amounts of gluconic acid, oxalic acid and small amounts of citric acid. The appearance and accumulation of organic acids was found to be highly pH dependent with the most active strain isolated from an ultra-acidic environment. The comparative strain differs entirely in the production of oxalic acid.This paper investigates the differences in some metabolites using Biolog FF Microplate™ system and the production of organic acids such as β-hydroxybutyric, p-hydroxyphenylacetic, and others. Another group of organic acids such as gluconic, oxalic and citric acid were studied during cultivation in a liquid medium. Four different Aspergillus niger (An) wild type strains were used as a model organism. Three strains, from the Banská Štiavnica – Šobov (An – Š), Pezinok (An – P) and Slovinky (An – Sl) localities were isolated from contaminated old mining areas with soil with ultra acidic to strong alkaline reactions. The fourth strain isolated from the Gabčíkovovo (An – G) locality was used for comparative purposes. According to the RAMP analysis, the strains are clustered into two groups, An – Š and An – P (similarity 82%), An – G and An – Sl (similarity 64%) which correlates with the pH values of the original environment. However, significant differences were found in metabolic processes in the reaction with a wide range of organic acids. In general, the reactions with D-lactic acid and D-malic acid correlate with the results of the RAMP analysis of fungal genotype similarities, the An – Š and An – P strains had an identical negative reaction, and an identical positive reaction was found in the An – Sl and An – G strains. During incubation the wild-type strains produced substantial amounts of gluconic acid, oxalic acid and small amounts of citric acid. The appearance and accumulation of organic acids was found to be highly pH dependent with the most active strain isolated from an ultra-acidic environment. The comparative strain differs entirely in the production of oxalic acid.This paper investigates the differences in some metabolites using Biolog FF Microplate™ system and the production of organic acids such as β-hydroxybutyric, p-hydroxyphenylacetic, and others. Another group of organic acids such as gluconic, oxalic and citric acid were studied during cultivation in a liquid medium. Four different Aspergillus niger (An) wild type strains were used as a model organism. Three strains, from the Banská Štiavnica – Šobov (An – Š), Pezinok (An – P) and Slovinky (An – Sl) localities were isolated from contaminated old mining areas with soil with ultra acidic to strong alkaline reactions. The fourth strain isolated from the Gabčíkovovo (An – G) locality was used for comparative purposes. According to the RAMP analysis, the strains are clustered into two groups, An – Š and An – P (similarity 82%), An – G and An – Sl (similarity 64%) which correlates with the pH values of the original environment. However, significant differences were found in metabolic processes in the reaction with a wide range of organic acids. In general, the reactions with D-lactic acid and D-malic acid correlate with the results of the RAMP analysis of fungal genotype similarities, the An – Š and An – P strains had an identical negative reaction, and an identical positive reaction was found in the An – Sl and An – G strains. During incubation the wild-type strains produced substantial amounts of gluconic acid, oxalic acid and small amounts of citric acid. The appearance and accumulation of organic acids was found to be highly pH dependent with the most active strain isolated from an ultra-acidic environment. The comparative strain differs entirely in the production of oxalic acid.[ABSTRACT FROM AUTHOR] - Published
- 2020
- Full Text
- View/download PDF
38. Fracture experiments of single grain boundaries in ductile metals
- Author
-
Kupka, Daniel and Huber, Norbert
- Subjects
crystal plasticity ,Mikro-Bruchversuche ,Kristallplastizität ,micro-fracture ,Engineering and allied operations ,Ingenieurwissenschaften [620] ,micro-compression ,Mikro-Druckversuche ,Ingenieurwissenschaften ,intergranularer Bruch ,Engineering and allied operations [620] ,intergranular fracture ,ddc:620 - Abstract
Eine Methode, zur Untersuchung des Bruches einzelner Korngrenzen in duktilen Metallen, wurde auf Basis von Biegeversuchen an Mikro-Balken entwickelt. Die plastische Deformation der Biegebalken wurde mittels eines Finite Elemente Kristallplastizitätsmodells vorhergesagt, welches mit Hilfe von Druckversuchen an einkristallinen Mikrosäulen kalibriert wurde. Die Bruchparameter der Korngrenzen wurden dann im Rahmen eines Kohäsivzonenmodells bestimmt., A method to investigate the fracture of a single grain boundary in ductile metals is developed based on micro-cantilever bending experiments. The plastic deformation of the cantilevers is predicted by a finite element crystal plasticity model which is calibrated making use of micro-compression experiments on single crystalline micro columns. The fracture parameters of a grain boundary are then determined in terms of a cohesive zone model.
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