Understanding Marine Microbes, the Driving Engines of the Ocean

When you hear the word microbes, what comes to your mind? Something much too small to see and that makes you fall ill? Just because some microbes cause diseases that does not mean they are all evil. For example, in the marine (ocean) environment, the vast majority of microbes are good ones. They are the “driving engines” of the ocean and are essential for the health of our whole planet. Unfortunately, most of the marine microbes and their interactions with the marine environment are poorly understood. So, it is important to get an idea of which microbes are helping us and how they are doing this. These data will provide scientists with the knowledge to fight against big global challenges, such as climate change and environmental pollution. Unfortunately, it is very hard to study marine microbes due to their microscopic size, huge diversity, and their big home – the ocean. Therefore, we would like to engage “citizen scientists” in this project to help us to sample marine microbes so that we can identify them

Aspects of noncommutative Lorentzian geometry for globally hyperbolic spacetimes

Connes' functional formula of the Riemannian distance is generalized to the Lorentzian case using the so-called Lorentzian distance, the d'Alembert operator and the causal functions of a globally hyperbolic spacetime. As a step of the presented machinery, a proof of the almost-everywhere smoothness of the Lorentzian distance considered as a function of one of the two arguments is given. Afterwards, using a $C^*$-algebra approach, the spacetime causal structure and the Lorentzian distance are generalized into noncommutative structures giving rise to a Lorentzian version of part of Connes' noncommutative geometry. The generalized noncommutative spacetime consists of a direct set of Hilbert spaces and a related class of $C^*$-algebras of operators. In each algebra a convex cone made of self-adjoint elements is selected which generalizes the class of causal functions. The generalized events, called {\em loci}, are realized as the elements of the inductive limit of the spaces of the algebraic states on the $C^*$-algebras. A partial-ordering relation between pairs of loci generalizes the causal order relation in spacetime. A generalized Lorentz distance of loci is defined by means of a class of densely-defined operators which play the r\^ole of a Lorentzian metric. Specializing back the formalism to the usual globally hyperbolic spacetime, it is found that compactly-supported probability measures give rise to a non-pointwise extension of the concept of events.Comment: 43 pages, structure of the paper changed and presentation strongly improved, references added, minor typos corrected, title changed, accepted for publication in Reviews in Mathematical Physic

Capturing and viewing gigapixel images

We present a system to capture and view "Gigapixel images": very high resolution, high dynamic range, and wide angle imagery consisting of several billion pixels each. A specialized camera mount, in combination with an automated pipeline for alignment, exposure compensation, and stitching, provide the means to acquire Gigapixel images with a standard camera and lens. More importantly, our novel viewer enables exploration of such images at interactive rates over a network, while dynamically and smoothly interpolating the projection between perspective and curved projections, and simultaneously modifying the tone-mapping to ensure an optimal view of the portion of the scene being viewed.publishe

Improvement of foundation soil behavior for Gründerzeit buildings in Austria using polyurethane resin injections

The second half of the XIX century signed a period of comprehensive industrial and cultural development in Austria known as Gründerzeit. The architecture was deeply influenced during this epoch by the construction of large masonry buildings, called “Gründerzeit Häuser”, which represent today the historical heritage of the most important Austrian cities. Due to the increasing demand for apartments in the centre of these cities, renovations and adaptations of existing buildings has been performed in the last decades. These modifications of the buildings structure represent, besides a business opportunity for the real estate economy, an increase/variation of the load for the foundations. Hence, the renovation and preservation of this architectural heritage often involve the improvement of the foundation soil. This article illustrates how the soil treatment with expanding polyurethane resin represents an efficient solution to achieve this goal. A case study of a historic building in the city of Salzburg is presented

Complement receptors regulate differentiation of bone marrow plasma cell precursors expressing transcription factors Blimp-1 and XBP-1

Humoral immune responses are thought to be enhanced by complement-mediated recruitment of the CD21–CD19–CD81 coreceptor complex into the B cell antigen receptor (BCR) complex, which lowers the threshold of B cell activation and increases the survival and proliferative capacity of responding B cells. To investigate the role of the CD21–CD35 complement receptors in the generation of B cell memory, we analyzed the response against viral particles derived from the bacteriophage Qβ in mice deficient in CD21–CD35 (Cr2−/−). Despite highly efficient induction of early antibody responses and germinal center (GC) reactions to immunization with Qβ, Cr2−/− mice exhibited impaired antibody persistence paralleled by a strongly reduced development of bone marrow plasma cells. Surprisingly, antigen-specific memory B cells were essentially normal in these mice. In the absence of CD21-mediated costimulation, Qβ-specific post-GC B cells failed to induce the transcriptional regulators Blimp-1 and XBP-1 driving plasma cell differentiation, and the antiapoptotic protein Bcl-2, which resulted in failure to generate the precursor population of long-lived plasma cells residing in the bone marrow. These results suggest that complement receptors maintain antibody responses by delivery of differentiation and survival signals to precursors of bone marrow plasma cells

Origin of clasts and matrix within the Milano and Napoli mud volcanoes, Mediterranean Ridge accretionary complex

Petrographic and mineralogical studies of clasts and matrix in the Milano and Napoli mud volcanoes drilled during Ocean Drilling Program Leg 160 provide important clues about depositional processes, provenance, and the tectonic setting of deepsea sediments that accumulated before genesis of the Mediterranean Ridge mud volcanoes. The clasts recovered from both mud volcanoes are mainly mudstone and claystone, calcareous siltstone, quartzose sandstone and siltstone, shallow-water-derived limestone, and pelagic carbonate. Biostratigraphic evidence indicates mainly early and middle Miocene ages for fossiliferous clasts, with the older microfossils being reworked. Textural evidence (grading) suggests that the clastic lithologies are turbidites. Sources of the sandstones were mainly plutonic igneous and subordinate metamorphic rocks. Sporadic, exceptionally well-rounded, quartz grains may be of eolian origin and were probably derived from the Precambrian basement of North Africa. Shallow-water-derived carbonates were also redeposited as calciturbidites, with variable admixing with siliciclastic and pelagic carbonate, which indicates shared depositional pathways. Pelagic carbonates (packstones) were redeposited basinward as calciturbidites from a deep-sea carbonate slope that formed part of the North African continental margin. During the middle Miocene, the background sedimentation was in situ pelagic carbonate. In addition, relatively rare, texturally immature, lithic sandstones include serpentinite, basalt, and radiolarian chert, of ophiolite-related origin. This material was derived from the orogenic areas to the north, possibly originally from the higher thrust sheets of Crete, before late Miocene and subsequent erosion and extensional downfaulting. The texture and composition of the mud and clay matrix provide clues about the mode of the mud volcanism. The matrix of the mud debris flows includes numerous, small, angular clasts of unfossiliferous claystone and shardlike fragments, which show pseudolamination, microshearing, and crosscutting veinlets, features that are taken as evidence for the involvement of high fluid pressure in clast and matrix formation (hyrofracturin

Tectonic setting and processes of mud volcanism on the Mediterranean Ridge accretionary complex: evidence from Leg 160.

Mud volcanism was initiated when overpressured muds rose through the Mediterranean Ridge accretionary prism. Early mud volcanism was marked by eruption of coarse clastic sediments forming small cones of debris flow deposits and turbidites, followed by eruption of large volumes of clast-rich matrix-supported debris flows. Eruption was accompanied by progressive subsidence to form moat-like features. Later, clast-poor mud flows spread laterally and built up a flat-topped cone (Napoli mud volcano). Clasts in the mud volcano sediments are mainly angular and up to 0.5 m in size. These clasts are dominated by claystone, sandstone, and limestone of early-middle Miocene age that were previously accreted. Matrix material of the mud breccias probably originated from Messinian evaporite-rich sediments located within the décollement zone beneath the accretionary wedge, at an estimated depth of 5-7 km. Pressure release triggered hydrofracturing of poorly consolidated mud near the seafloor. Eruption was accompanied by release of large volumes of hydrocarbon gas. Conditions were suitable for gas hydrate genesis at shallow depths beneath the seafloor at the Milano mud volcano. The mud volcanism is probably related to backthrusting concentrated along the rear of the accretionary wedge near a backstop of continental crust to the north. Clasts within the mud breccias were mainly derived from the North African passive margin, but subordinate lithoclastic ophiolite-related material was also derived from the north, probably from now largely obliterated higher thrust sheets of Crete. Comparisons show that in contrast to other mud volcanoes both on the seafloor (Barbados) and on land (Trinidad), which are usually relatively transient features, mud volcanism on the Mediterranean Ridge has persisted for >1 m.y. A revised hypothesis of mud volcanism at the Ocean Drilling Program sites is proposed, in relation to progressive tectonic evolution of the Mediterranean Ridge accretionary complex