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A negative shift in the calcium isotopiccomposition of marine carbonate rocksspanning the end-Permian extinction horizonin South China has been used to arguefor an ocean acidification event coincidentwith mass extinction. This interpretationhas proven controversial, both because theexcursion has not been demonstrated acrossmultiple, widely separated localities, and becausemodeling results of coupl

Conodonts have been a key tool for biostratigraphical, evolutionary and palaeobiogeographical studies, and the GermanicBasin has been one of the most important regions for these studies. However, few modern studies provide systematic data onthe mainly endemic conodonts of the Middle Triassic Germanic Basin. Here we document conodonts from two sections inGermany, one Bithynian in age and the other

The end-Permian mass extinction was the most severe biotic crisis in Earth's history. In its direct aftermathmicrobial communities colonized some of the space left vacant after the severe decline of skeletal metazoans.The Permian-Triassic boundary microbialites were peculiarly abundant on low-latitude shallow-marine carbonateshelves of central Tethyan continents. Armenia features particularly well

The cause of the Triassic-Jurassic (Tr-J) boundary biotic crisis, one of the ‘Big Five’ mass extinctions of the Phanerozoic, remains controversial. In this study, we analyzed multiple sulfur-isotope compositions (δ33S, δ34S and δ36S) of pyrite and Spy/TOC ratios in two Tr-J successions (Mariental, Mingolsheim) from the European Epicontinental Seaway (EES) in order to better document ocean-redox va

Preeclampsia (PE) is an important pregnancy complication that affects 3-8% of women worldwide and is a leading cause of maternal and fetal morbidity and mortality. It is known that PE is associated with placental dysfunction, resulting in hypoxia, oxidative stress, altered metabolism and production of inflammatory cytokines. Hypoxia could enhance erythropoiesis and induce non-erythroid hemoglobin

The work presented in this thesis is motivated by the need to reliably operate a compression-ignition engine in a partially premixed combustion (PPC) mode. Partially premixed combustion is a low temperature combustion concept, where the ignition delay is prolonged to enhance fuel-air mixing in the combustion chamber before the start of combustion. A premixed combustion process, in combination with

The HIV-1 envelope mutates rapidly to evade recognition and killing, and is a major target of humoral immune responses and vaccine development. Identification of common epitopes for vaccine development have been complicated by genetic variation on both virus and host levels. We studied HIV-1 envelope gp120 evolution in 12 Chinese former plasma donors infected with a purportedly single founder viru

3D-macroporous chitosan-based scaffolds (cryogels) were produced via growth of metal-polymer coordinated complexes and electrostatic interactions between oppositely charged groups of chitosan and metal ions under subzero temperatures. A mechanism of reduction of noble metal complexes inside the cryogel walls by glutaraldehyde is proposed, which produces discrete and dispersed noble metal nanoparti

Monitoring of the molecular motions and secondary structures of gliadin (Gli) and glutenin (Glu) in blends with 10, 20, 30, and 40% glycerol was performed by solid-state (SS) and time domain (TD) NMR spectroscopy. Increasing the glycerol content increased the relative amount of β-sheets and disordered structures, while decreasing α-helices in Gli/Glu–glycerol blends studied by 13C CPMAS NMR. For ≥

This paper investigates the petrogenesis of the Seqi Ultramafic Complex, which covers a total area of approximately 0.5 km2. The ultramafic rocks are hosted by tonalitic orthogneiss of the ca. 3000 Ma Akia terrane with crosscutting granitoid sheets providing an absolute minimum age of 2978 ± 8 Ma for the Seqi Ultramafic Complex. The Seqi rocks represent a broad range of olivine-dominated plutonic

Addressing urban sustainability challenges requires changes in the way systems of provision and services are designed, organised and delivered. In this context, two promising phenomena have gained interest from the academia, the public sector and the media: “smart cities” and “urban sharing”. Smart cities rely on the extensive use of information and communications technology (ICT) to increase effi

Fatty acid esters of hydroxy fatty acids (FAHFAs) are a recently discovered class of endogenous lipids with antidiabetic and anti-inflammatory activities. Interest in these lipids is due to their unique biological activites and the observation that insulin-resistant people have lower palmitic acid esters of hydroxystearic acid (PAHSA) levels, suggesting that a FAHFA deficiency may contribute to me

Many bridges are approaching or have already passed their expected service life. For steel bridges, fatigue is often the decisive degradation phenomenon that theoretically puts restrictions on a continued use. At the same time, fatigue is also afflicted with large uncertainties on the resistance side as well as on the action effect side. An accurate assessment of the service life will require meas

The argument has two related parts: firstly, we are witnessing an “epistemic” crisis in public spheres that threatens to undermine political agency. This crisis has to do with the massive amounts and speed of information, the processes by which we construct knowledge, as well as the new forms of knowledge deriving from digital technologies. Many developments in information technologies benefit dem

The Fourier slice theorem for the standard Radon transform generalizes to a Laplace counterpart when considering the exponential Radon transform. We show how to use this fact in combination with algorithms for the unequally spaced fast Laplace transform to construct fast and accurate methods for computing both the forward exponential Radon transform and the corresponding back-projection operator.

The Ordovician biodiversification has been recognized since the 1960s; the term ‘The Great Ordovician Biodiversification Event’, abbreviated by many as the ‘GOBE’, has been used for the past 20 years. The conceptual development and terminology applied to this crucial episode in marine life signify its considerable complexity. The GOBE includes successive biodiversity phases of the pelagic and bent

We introduce and briefly summarize a collection of papers contextualizing the onset of the Great Ordovician Biodiversification Event, initiated during the first meeting of IGCP project 653 at Van Mildert College, Durham University, UK, in September 2016.

Highly accurate location information is a key facilitator to stimulate future services for the commercial and public sectors. Positioning and tracking of absolute positions of wireless nodes usually requires information provided from technical infrastructure, e.g., satellites or fixed anchor nodes, whose maintenance is costly and whose limited operating coverage narrows the positioning service. In