Browsing by Subject "Greece"

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    Bioenergetic characterization of a shallow-sea hydrothermal vent system: Milos Island, Greece
    (Public Library of Science, 2020-06-05) Lu, Guang-Sin; LaRowe, Douglas E.; Fike, David A.; Druschel, Gregory K.; Gilhooly, William P., III; Price, Roy E.; Amend, Jan P.; Earth and Environmental Sciences, School of Science
    Shallow-sea hydrothermal systems, like their deep-sea and terrestrial counterparts, can serve as relatively accessible portals into the microbial ecology of subsurface environments. In this study, we determined the chemical composition of 47 sediment porewater samples along a transect from a diffuse shallow-sea hydrothermal vent to a non-thermal background area in Paleochori Bay, Milos Island, Greece. These geochemical data were combined with thermodynamic calculations to quantify potential sources of energy that may support in situ chemolithotrophy. The Gibbs energies (ΔGr) of 730 redox reactions involving 23 inorganic H-, O-, C-, N-, S-, Fe-, Mn-, and As-bearing compounds were calculated. Of these reactions, 379 were exergonic at one or more sampling locations. The greatest energy yields were from anaerobic CO oxidation with NO2- (-136 to -162 kJ/mol e-), followed by reactions in which the electron acceptor/donor pairs were O2/CO, NO3-/CO, and NO2-/H2S. When expressed as energy densities (where the concentration of the limiting reactant is taken into account), a different set of redox reactions are the most exergonic: in sediments affected by hydrothermal input, sulfide oxidation with a range of electron acceptors or nitrite reduction with different electron donors provide 85~245 J per kg of sediment, whereas in sediments less affected or unaffected by hydrothermal input, various S0 oxidation reactions and aerobic respiration reactions with several different electron donors are most energy-yielding (80~95 J per kg of sediment). A model that considers seawater mixing with hydrothermal fluids revealed that there is up to ~50 times more energy available for microorganisms that can use S0 or H2S as electron donors and NO2- or O2 as electron acceptors compared to other reactions. In addition to revealing likely metabolic pathways in the near-surface and subsurface mixing zones, thermodynamic calculations like these can help guide novel microbial cultivation efforts to isolate new species.
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    Country Report 2018: Greece
    (2018) Giannopoulou, Christina
    The Greek Constitution in article 12 clearly grants all Greek people the right to form nonprofit associations and unions, in compliance with the law. Moreover, article 14 paragraph 1 guarantees free expression indicating that every person may express and propagate his thoughts orally, in writing and through the press in compliance with the laws of the State. However, there is no specific legal framework for the formation and operation of POs in Greece. In this context, a PO can be founded under the current provisions of the civil code as a not-for-profit legal person of private law (e.g. a union of persons, an association, a foundation, a civil non-profit company, a collection committee etc.).
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    What now for Greece and the euro?
    (The Conversation US, Inc., 2015-07-09) McCormick, John; Political Science, School of Liberal Arts