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Coupled Hydromechanical Modelling of a Vertical Hydraulic Sealing System Based on the Sandwich PrincipleNARA Subscribed
For the shaft sealing of a repository for radioactive waste, a Sandwich sealing system was developed by KIT-CMM consisting of bentonite-based sealing segments (DS) and sand mixture-based equipotential segments (ES). To demonstrate the functionality of the Sandwich sealing system, various laboratory tests (MiniSandwich tests and semi-technical scale experiments) have been carried out before a large-scale experiment has been imp...
Zinc, carbon, and oxygen isotopic variations associated with the Marinoan deglaciationNARA Subscribed
The "Snowball Earths" were cataclysmic events during the late Neoproterozoic's Cryogenian period (720-635 Ma) in which most, if not all, of Earth’s surface was covered in ice. Paleoenvironmental reconstructions of these events utilize isotopic systems, such as Δ 17 O and barium isotopes of barites. Other isotopic systems, such as zinc (Zn), can reflect seawater composition or environmental conditions (e.g., temperature changes...
A comparison of the chemo- and radiotoxicity of thorium and uranium at different enrichment gradesNARA Subscribed
Uranium and thorium are heavy metals, and all of their isotopes are radioactive, so it is impossible to study chemical effects entirely independent of the radiation effects. In the present study, we tried to compare the chemo- and radiotoxicity of both metals, taking into account deterministic radiation damages reflected by acute radiation sickness and stochastic radiation damages leading to long-term health impairments (e.g.,...
Prolonging survival in good health is a fundamental societal goal. However, the leading determinants of disability-free survival in healthy older people have not been well established. Data from ASPREE, a bi-national placebo-controlled trial of aspirin with 4.7 years median follow-up, was analysed. At enrolment, participants were healthy and without prior cardiovascular events, dementia or persistent physical disability. Disab...
Apple replant disease (ARD) negatively affects growth and yield of apple plants worldwide. Fungi belonging to the Nectriaceae have often been isolated from roots grown in replant soils and thus are proposed among others as one biotic cause of the disease complex. Microscopic analyses of ARD-affected roots revealed characteristic symptoms associated with fungal infection sites. Here, two extraction methods of such tissue sites...
Microbial oxidation of nitrogen supplied as selected organic nitrogen compounds in the South Atlantic BightNARA Subscribed
Dissolved organic nitrogen (DON) can account for a large fraction of the dissolved nitrogen (N) pool in the ocean, but the cycling of marine DON is poorly understood. Recent discoveries that urea‐ and cyanate‐N can be oxidized by some strains of Thaumarchaeota suggest that these abundant microbes may be able to access and oxidize a fraction of the DON pool. However, measurements of the oxidation of N supplied as DON compounds...
Oxidation of urea‐derived nitrogen by thaumarchaeota‐dominated marine nitrifying communitiesNARA Subscribed
Summary Urea nitrogen has been proposed to contribute significantly to nitrification by marine thaumarchaeotes. These inferences are based on distributions of thaumarchaeote urease genes rather than activity measurements. We found that ammonia oxidation rates were always higher than oxidation rates of urea‐derived N in samples from coastal Georgia, USA (means ± SEM: 382 ± 35 versus 73 ± 24 nmol L −1 d −1 , Mann‐Whitney U‐test...
Spatial food‐web structure in the eastern tropical P acific O cean based on compound‐specific nitrogen isotope analysis of amino acidsNARA Subscribed
The effective evaluation of trophic interactions in pelagic food webs is essential for understanding food web ecology, conservation biology, and management. We tested the applicability of compound‐specific isotope analysis of amino acids (CSIA‐AA) for (1) characterizing trophic positions (TPs) of nine species from four trophic groups (tunas, squids, myctophids, and euphausiids) within a pelagic food web in the eastern tropical...
A common challenge in phylogenetic reconstruction is to find enough suitable genomic markers to reliably trace splitting events with short internodes. Here, we present phylogenetic analyses based on genomewide single‐nucleotide polymorphisms ( SNP s) of an enigmatic avian radiation, the subspecies complex of Afrocanarian blue tits ( Cyanistes teneriffae ). The two sister species, the Eurasian blue tit ( Cyanistes caeruleus ) a...
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