Bewertung ausgewählter Bodenfunktionen von Wattböden im Verlauf der Seekabeltrasse Manslagt – Borkum

Wegen der steigenden Anzahl gebauter und geplanter Offshore-Windparks nimmt die Zahl der Verlegung von Kabeln in Böden des Deutschen Wattenmeeres stetig zu. Auswirkungen baulicher Eingriffe werden für Festland-Böden über die Bodenfunktionsbewertung eingestuft, für Wattböden bislang aber nicht. Für die im Zeitraum Juli/August 2013 durchgeführte Baumaßnahme zur Verlegung eines Seekabels mittels Vibrationsschwert zwischen Manslagt (Ostfriesland) und Borkum wurden ausgewählte Boden-Teilfunktionen untersucht (z.B. Standortpotential für Bodenorganismen und Archivfunktion). Die bodenkundliche Datenerhebung fand auf der Kabeltrasse und im benachbarten, baulich unbeeinflussten Referenzgebiet statt. Ergebnisse benthosbiologischer Untersuchungen wurden berücksichtigt. Auf dieser Datenbasis wurde geprüft, ob Unterschiede zwischen a) Kabeltras-se/Referenzgebiet, b) Jahre 2012/2013 oder c) verschiedenen Beprobungstiefen bestehen. Vielfach waren Veränderungen, aber nur vereinzelt signifikante Unterschiede nachzuweisen, was auf die hohe Dynamik des Wattenmeeres und die Anpassungsfähigkeit der Organismen zurückzuführen ist. In der Tendenz ist die Textur nach den Baumaßnahmen im Jahr 2013 grobkörniger als im Vorjahr. Veränderungen sind bei den Carbonatgehalten festzustellen, die im Jahr 2013 signifikant höher liegen als im Jahr 2012 und im Sandwatt auf der Kabeltrasse tendenziell höher sind als an den Referenzstandorten. Der Tiefengradient der Redoxpotentiale und die typische Fo-/Fr-Horizontierung in Wattböden haben sich bereits wieder entwickelt. Veränderungen der Bewertung der ausgewählten Bodenfunktionen von Wattböden sind in diesem Fallbeispiel nicht nachzuweisen. Effekte der baulichen Maßnahmen wie der Verlauf des Kabelschlitzes oder Verankerungen des Verlegepontons mit Gräben und Mulden sind sichtbar. Kumulative Effekte von Kabellegungen sind momentan nicht berücksichtigt

The global warming potential and the material utility of PET and bio-based PEF bottles over multiple recycling trips

Biomass use and recycling are among the few options to reduce the greenhouse gas (GHG) emissions of the growing plastics sector. The bio-based plastic polyethylene furanoate (PEF) is a promising alternative to polyethylene terephthalate (PET), in particular for small bottle applications. For the first time, we assessed the life cycle global warming potential (GWP) for 250 mL PET and PEF bottles over multiple mechanical (MR) and chemical (CR) recycling trips in the Netherlands. We found that bio-based PEF would offer 50–74% lower life cycle GHG emission after one recycling trip compared to PET, depending on the waste management case. Our results also show that deposit-based recycling systems significantly reduce the cumulative cradle-to-grave net GHG emissions for both bottle types, especially when multiple recycling trips are applied. We propose complementary material utility (MU) indicators to reveal synergies and trade-offs between circularity and GWP: While deposit-based CR shows the best performance in terms of MU, it falls behind deposit-based MR when it comes to net GHG emissions due to the energy intensity of CR. Hence, combining mechanical and chemical recycling could contribute to achieving the goals of the circular economy and climate change mitigation alike

Diversity patterns and community structure of the ground-associated macrofauna along the beach-inland transition zone of small tropical islands

Biodiversity follows distinct and observable patterns. Where two systems meet, biodiversity is often increased, due to overlapping occurrence ranges and the presence of specialized species that can tolerate the dynamic conditions of the transition zone. One of the most pronounced transition zones occurs at shores, where oceans and terrestrial habitat collide, forming the shore–inland transition zone. The relevance of this transition zone in shaping a system’s community structure is particularly pronounced on small islands due to their high shore-to-inland-area ratio. However, the community structure of insular faunas along this transition zone is unknown. Here, we investigated the diversity patterns along the beach–inland transition zone of small islands and tested the hypothesis that species diversity increases toward the transition zone where beach and interior habitat meet. By measuring environmental parameters, resource availability, and ground-associated macrofauna diversity along transects running across the beach–inland transition zone, we show that a gradual change in species composition from beach to the inland exists, but neither taxa richness, diversity, nor overall abundance changed significantly. These findings offer important insights into insular community structure at the transition zone from sea to land that are relevant to better understand the dynamic and unique characteristics of insular ecosystems

IL28B, HLA-C, and KIR Variants Additively Predict Response to Therapy in Chronic Hepatitis C Virus Infection in a European Cohort: A Cross-Sectional Study

Vijayaprakash Suppiah and colleagues show that genotyping hepatitis C patients for the IL28B, HLA-C, and KIR genes improves the ability to predict whether or not patients will respond to antiviral treatment

Nature's lessons in design: nanomachines to scaffold, remodel and shape membrane compartments.

Compartmentalisation of cellular processes is fundamental to regulation of metabolism in Eukaryotic organisms and is primarily provided by membrane-bound organelles. These organelles are dynamic structures whose membrane barriers are continually shaped, remodelled and scaffolded by a rich variety of highly sophisticated protein complexes. Towards the goal of bottom-up assembly of compartmentalised protocells in synthetic biology, we believe it will be important to harness and reconstitute the membrane shaping and sculpting characteristics of natural cells. We review different in vitro membrane models and how biophysical investigations of minimal systems combined with appropriate theoretical modelling have been used to gain new insights into the intricate mechanisms of these membrane nanomachines, paying particular attention to proteins involved in membrane fusion, fission and cytoskeletal scaffolding processes. We argue that minimal machineries need to be developed and optimised for employment in artificial protocell systems rather than the complex environs of a living organism. Thus, well-characterised minimal components might be predictably combined into functional, compartmentalised protocellular materials that can be engineered for wide-ranging applications

Multi-messenger observations of a binary neutron star merger

On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta

Searching for VHE gamma-ray emission associated with IceCube neutrino alerts using FACT, H.E.S.S., MAGIC, and VERITAS

The realtime follow-up of neutrino events is a promising approach to searchfor astrophysical neutrino sources. It has so far provided compelling evidencefor a neutrino point source: the flaring gamma-ray blazar TXS 0506+056 observedin coincidence with the high-energy neutrino IceCube-170922A detected byIceCube. The detection of very-high-energy gamma rays (VHE, $\mathrm{E} >100\,\mathrm{GeV}$) from this source helped establish the coincidence andconstrained the modeling of the blazar emission at the time of the IceCubeevent. The four major imaging atmospheric Cherenkov telescope arrays (IACTs) -FACT, H.E.S.S., MAGIC, and VERITAS - operate an active follow-up program oftarget-of-opportunity observations of neutrino alerts sent by IceCube. Thisprogram has two main components. One are the observations of known gamma-raysources around which a cluster of candidate neutrino events has been identifiedby IceCube (Gamma-ray Follow-Up, GFU). Second one is the follow-up of singlehigh-energy neutrino candidate events of potential astrophysical origin such asIceCube-170922A. GFU has been recently upgraded by IceCube in collaborationwith the IACT groups. We present here recent results from the IACT follow-upprograms of IceCube neutrino alerts and a description of the upgraded IceCubeGFU system.<br

Broadband Multi-wavelength Properties of M87 during the 2017 Event Horizon Telescope Campaign

Abstract: In 2017, the Event Horizon Telescope (EHT) Collaboration succeeded in capturing the first direct image of the center of the M87 galaxy. The asymmetric ring morphology and size are consistent with theoretical expectations for a weakly accreting supermassive black hole of mass ∼6.5 × 109 M ⊙. The EHTC also partnered with several international facilities in space and on the ground, to arrange an extensive, quasi-simultaneous multi-wavelength campaign. This Letter presents the results and analysis of this campaign, as well as the multi-wavelength data as a legacy data repository. We captured M87 in a historically low state, and the core flux dominates over HST-1 at high energies, making it possible to combine core flux constraints with the more spatially precise very long baseline interferometry data. We present the most complete simultaneous multi-wavelength spectrum of the active nucleus to date, and discuss the complexity and caveats of combining data from different spatial scales into one broadband spectrum. We apply two heuristic, isotropic leptonic single-zone models to provide insight into the basic source properties, but conclude that a structured jet is necessary to explain M87’s spectrum. We can exclude that the simultaneous γ-ray emission is produced via inverse Compton emission in the same region producing the EHT mm-band emission, and further conclude that the γ-rays can only be produced in the inner jets (inward of HST-1) if there are strongly particle-dominated regions. Direct synchrotron emission from accelerated protons and secondaries cannot yet be excluded