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Ervin Bauer is one of the first theoretical biologists distancing his ideas both from vitalism and mechanicism. He formulated the principle of permanent non-equilibrium of living systems (Bauer’s principle) in terms of thermodynamics in 1920. Bauer’s scientific path can be divided into three periods. In the early 1920s he proposed his principle as an axiom that cannot be derived from contemporary natural sciences. In the late 1920s he reformulated it in a way that it could be subjected to experimental testing. Summarizing his views in the 1930s in his book, Theoretical Biology, he tried to show that his axiom is indeed the fundamental principle of biology. This later view was anachronistic in spite of many striking insights of Bauer. The energetic formulation of Bauer’s principle is, however, a realistic characterization of living organisms and it can be derived from the theory of open systems — in fact it contributed to the formulation of that theory. Bauer’s principle can be incorporated into non-linear thermodynamics of irreversible processes.

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In 2002 several chambergraves from the 10 th century were excavated in the old town of Kiev. The richest equipped female grave — chambergrave No. 49, 1999 — from beneath the St. Michael’s Golden Domes from the city of Izyaslaus/Izjaslavs and the most important of the male chambergraves from the city of Vladimir are focused in this article. The breast jewellery and a round filigree decorated brooch from the female grave as well as the sword with its scabbard’s chape and the metal fittings of a leather bag from the male grave are taken into special consideration. Concerning construction and equipment a close connection to the chambergraves from Birka can be detected. The dead belonged to a leading person subgroup which via Scandinavia got into contact with west European Christianity.

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The thermal behaviours of alkylammonium and potassium N-alkylthiocarbamates of general formula (RNH3) (RHNCXY) (where X= Y= S or X= S and Y= 0; R=n-C3H3,i-C3H3,n-C4H9,i-C4H9 orc-C6H11) and K(RHNCOS) (where R=CH3, C2H5,n-C3H7,i-C3H7,n-C4H9,i-C4H9 orc-C6H11) were investigated. The decomposition mechanisms exhibit a similar character for all studied compounds. In the course of thermolysis symmetric dialkylureas and dialkylthioureas, as well as amines, CS2 (or COS) and H2S are formed. The alkylammonium thiocarbamates decompose without any residue, whereas with potassium monothiocarbamates potassium sulfate is left as a residue. For the process of urea and thiourea formation during the first step of decomposition, the activation energies were computed for some compounds.

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Abstract  

This pape discusses the use, of stable Cs as an activatable tracer for measuring performance of plant root intrusion barriers for solid waste disposal site cover systems. Experiments conducted at small-scale demonstrate the effectiveness and practicality of the technique and suggest that the methodology has application to a better understanding of plant root ecology.

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Abstract  

2-[18F]-nicotinic acid diethylamide was prepared by nucleophilic aromatic substitution in an acetamide melt of the corresponding chloro-compound and purified by high pressure liquid chromatography. Optimization of the reaction conditions led to a maximum radiochemical yield of about 50% within less than one half-life of18F. Tissue distribution of 2-[18F]-nicotinic acid diethylamide in various organs of mice showed a very fast accumulation of activity in the brain (mean body concentration MBC-239%) with a brain to blood ratio of 1.34.

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The biological and toxicological importance of molybdenum in the environment and in the nutrition of plants, animals and man

Part IV: The molybdenum intake of adults with mixed and vegetarian diets in Germany and Mexico (duplicate portion studies)

Authors: M. Anke, S. Holzinger, M. Seifert, R. Müller and U. Schäfer

The molybdenum intake by German and Mexican adults (21 test populations) aged 20 to 69 years with mixed and ovolactovegetarian diets were determined. Each test group consisted of at least 7 women and 7 men, which collected all consumed foodstuffs and beverages as visually estimated duplicates on 7 successive days. The balance studies were carried out with 8 test populations (women and men) with mixed and ovolactovegetarian diets. People with mixed diet in Germany consumed, on average, 89 (women) and 100 μg Mo/day (men), whereas in Mexico they took in 160 and 210 μg Mo/day, respectively. German ovolactovegetarians consumed ∼175 μg Mo/day. Male adults of Germany consumed 21% more molybdenum than women. This difference is the result of a 24% higher dry matter intake by males. The residence place, its geological origin and time of examination influenced the molybdenum intake significantly (60–115 μg Mo/day). The normative molybdenum requirement of adults amounts to 25 μg/day, with women needing 20 and men 25 μg/day. As a rule approximately only one-third of the absorbed molybdenum is excreted renally, the rest faecally. Breast feeding mothers excreted 11% via milk, 56% faecally and 33% renally. The apparent absorption rate of molybdenum amounted to 37% in humans with mixed and vegetarian diets, whereas it reached 44% in breast-feeding mothers. The calculation of molybdenum consumption (basket method) overestimated the molybdenum intake by 50% in comparison to chemical determination by the duplicate portion method.

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The effect of a pure endoxylanase (Xyn2) and endoglucanase (EgII) from Trichoderma reesei on bread flour quality were compared to a commercial endoxylanase from Aspergillus niger (Com-xyl) and a cellulase-xylanase cocktail from T. reesei (Cel-xyl). Effects of these enzymes on dough quality, bread weight, height and crumb softness were analysed. Results obtained during commercial-scale baking tests often differed from those obtained during laboratory-scale tests; indicating that results from laboratory-scale baking tests cannot be extrapolated to commercialscale bread production. Low levels of endoxylanase activity benefited bread height and volume without affecting slice brightness in commercial-scale tests. The addition of endoglucanases and α-amylases can also be advantageous resulting in less endoxylanase activity required to obtain similar results.

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Authors: M. Seifert, W. Dorn, R. Müller, S. Holzinger and M. Anke

The molybdenum content of food in Germany varies between 10 and 6000 μg kg −1 dry matter. Cereal products, sugar- and starch-rich food, luxury food, bread, rolls, cake, spices and most kinds of fruits deliver 10–400 μg Mo kg −1 dry matter. Herbs and vegetables are generally rich in molybdenum, for example, cucumber can store up to 4000 μg Mo kg −1 dry matter as well as pulses. Animal products, with exception of liver and kidney, are poor in molybdenum. Vegetable foodstuffs as part of mixed diets in Germany deliver 70% of the human intake, animal foodstuffs about 20% and beverages less than 10%.

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Authors: M. Anke, M. Seifert, Sylvia Holzinger, R. Müller and U. Schäfer

Molluscs and insects accumulate between 200 and 1050 μg Mo/kg of dry matter. Mice and vole species incorporate 350–650 μg Mo/kg, whereas shrews store 1500–2500 μg Mo/kg, i.e. insectivores have significantly higher molybdenum contents than rodents. The amounts of molybdenum accumulated by wild and domestic mammals are highest in the liver and kidneys, and lowest in muscle tissue and hair. The molybdenum status of mammals is reflected by all tissues tested except the heart. The best indicators of molybdenum deficiency and intoxication are liver, kidneys, blood and milk. The intrauterine storage of molybdenum in mammals is low. The milk delivers sufficient molybdenum amounts to the new borns. In man, the transfer of molybdenum follows the same rules as those found in mammals.

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