University of Konstanz

About: University of Konstanz is a education organization based out in Konstanz, Baden-Württemberg, Germany. It is known for research contribution in the topics: Population & Visualization. The organization has 12115 authors who have published 27401 publications receiving 951162 citations. The organization is also known as: University of Constance & Universität Konstanz.

A Framework for the Comparative Study of Social Services

Abstract: Comparative research on welfare states has most focused on social transfers as the depen dent variable As demographic changes make social services increasingly important ingredi ents of welfare st

Influence of temperature on energetics of hydrogen metabolism in homoacetogenic, methanogenic, and other anaerobic bacteria

Abstract: Hydrogen consumption by various thermophilic, mesophilic and/or psychrotrophic homoacetogens and methanogens was measured at temperatures between 4 and 80°C. Within the tolerated temperature range H2 was consumed until a final H2 threshold partial pressure was reached. H2 thresholds generally decreased with temperature, parallel to the values calculated from the thermodynamics prevailing under culture conditions, i.e. the Gibbs free energy (ΔG) of H2 oxidation corrected for temperature by both the free-energy form of the Nernst equation and the Van't Hoff equation. The difference between the observed and the calculated H2 partial pressures gives the minimum energy required for H2 utilization being about-5 to-6 kJ/mol H2 for the homoacetogenes and-9 to-12 kJ/mol H2 for methanogens. The temperature dependence of the standard Gibbs free energy (ΔG0) as described by the Van't Hoff equation apparently became the more important for thermodynamics as well as H2 thresholds the more the temperature deviated from standard conditions (i.e. 25°C). Correction factors for calculation of temperature-corrected ΔG infT sup0 are presented for various H2-producing and H2-consuming reactions.

Hydrogen turnover by psychrotrophic homoacetogenic and mesophilic methanogenic bacteria in anoxic paddy soil and lake sediment

Abstract: The effect of temperature on CH4 production, turnover of dissolved H2, and enrichment of H2-utilizing anaerobic bacteria was studied in anoxic paddy soil and sediment of Lake Constance. When anoxic paddy soil was incubated under an atmosphere of H2/CO2, rates of CH4 production increased 25°C, but decreased at temperatures lower than 20°C. Chloroform completely inhibited methano-genesis in anoxic paddy soil and lake sediment, but did not or only partially inhibit the turnover of dissolved H2, especially at low incubation temperatures. Cultures with H2 as energy source resulted in the enrichment of chemolithotrophic homoacetogenic bacteria whenever incubation temperatures were lower than 20°C. Hydrogenotrophic methanogens could only be enriched at 30°C from anoxic paddy soil. A homoacetogen