Neue Kennwerte für die Wasserbindung in Böden - Ergebnisse der Abstimmung zwischen dem Personenkreis Wasserhaushaltstabellen der Ad-hoc-AG Boden und dem DWA

Mit den vorliegenden Diagrammen und Tabellen liegen bundesweit abgestimmte Grundlagen für die Einschätzung des Wasser- und Lufthaushaltes von Böden vor. Die Werteschwankungen von Wasserge-halten in verschiedenen Porenbereichen des Bodens können über die graphische Datenauswertung auf der Basis des Korn-größendiagramms schlüssig abgebildet werden. Gegenüber der bodenkundlichen Kartieranleitung (Ad-hoc-AG Boden 2005) liegen folgende Änderungen bzw. Erweiterungen vor: - Schätzrahmen mit Werten für 5 Trockenrohdichten - Schätzrahmen mit Angaben für pF 2,5 - Schätzrahmen mit Angaben für die Frühjahrsfeuchte - Diagramme auf der Basis des Korngrößendreiecks - Erweiterung der Tabelle mit Zuschlägen in Abhängigkeit von der Humusstufe und Bodenart für pF 2,5 Schätzrahmen und Diagramme bieten ein aufeinander abgestimmtes Gesamtpaket für die feldbodenkundliche Arbeit

Common Peptides Study of Aminoacyl-tRNA Synthetases

Aminoacyl tRNA synthetases (aaRSs) constitute an essential enzyme super-family, providing fidelity of the translation process of mRNA to proteins in living cells. They are common to all kingdoms and are of utmost importance to all organisms. It is thus of great interest to understand the evolutionary relationships among them and underline signature motifs defining their common domains.We utilized the Common Peptides (CPs) framework, based on extracted deterministic motifs from all aaRSs, to study family-specific properties. We identified novel aaRS–class related signatures that may supplement the current classification methods and provide a basis for identifying functional regions specific to each aaRS class. We exploited the space spanned by the CPs in order to identify similarities between aaRS families that are not observed using sequence alignment methods, identifying different inter-aaRS associations across different kingdom of life. We explored the evolutionary history of the aaRS families and evolutionary origins of the mitochondrial aaRSs. Lastly, we showed that prevalent CPs significantly overlap known catalytic and binding sites, suggesting that they have meaningful functional roles, as well as identifying a motif shared between aaRSs and a the Biotin-[acetyl-CoA carboxylase] synthetase (birA) enzyme overlapping binding sites in both families.The study presents the multitude of ways to exploit the CP framework in order to extract meaningful patterns from the aaRS super-family. Specific CPs, discovered in this study, may play important roles in the functionality of these enzymes. We explored the evolutionary patterns in each aaRS family and tracked remote evolutionary links between these families

Damage to the Historic Town of Staufen (Germany) Caused by Geothermal Drillings through Anhydrite-Bearing Formations

Shallow geothermal systems for the heating and cooling of buildings will play an important role in the future renewable energy supply. Especially in dense settlements the geothermal energy utilization for facility heating and cooling is very promising. Therefore, it is important to analyse the damage to Staufen im Breisgau (Germany). In September of 2007, seven geothermal borehole heat exchanger (BHE) drillings were performed in a small square directly adjacent to the 16th century town hall in the centre of the town. These led to enormous structural damage to buildings as a function of four different geological parameters: artesian groundwater, two interacting karst formations, strong tectonization, and a swellable anhydrite formation. Some weeks after termination of the well construction, uplift started, and recently (March 2010) reached a magnitude of approximately 26 cm. Actually, some 250 buildings (March 2010) are involved; showing cracks, tilting, and other effects of the differential swelling movements beneath the foundations. Surface uplifts with rate up to 10 mm/month have been determined using high-resolution spaceborne radar data and radarinterferometric techniques. These amplitudes correlate with data from benchmarks of terrestrial geodetic surveyng. Besides the uplift due to the swelling processes, future problems could arise from the fact that the gypsum formed from the swelled anhydrite is soluble in water. Thus, sinkholes and other karst related phenomena may occur

A method for assessing adhesion of clays to tunneling machines

Tunnel boring machines passing through cohesive soils sometimes experience significant clogging, leading to delays and increased costs. The paper describes a test to assess the likelihood of adhesion problems occurring, simulating the situation where a clay sticks to the cutting wheel of the machine. The results of tests using kaolin clay suggest that the adhesion changes with the compression force. Further studies are being undertaken to elucidate the factors which influence this, including clay mineralogy and roughness of the face of the cutting wheel. It is hoped that the work will lead to an industrial standard method of assessing adhesion which can be used in site investigation and on site