Moden nordatlantischer Klimavariabilität

According to Rowan T. Sutton and Miles R. Allen (hereafter: SA) there is a chance to enhance the predictability of decadal climate variability over the northern European sector. This enhancement supposedly originates from the horizontal advection of SST anomalies along the Gulf Stream and North Atlantic Current (NAC). SA suggest that fluctuations in SST which arise from advection might be predictable, so would be their impact on the atmosphere. The described advection mechanism is subject of this work, analyzing mainly NCEP/NCAR and COADS datasets of various meteorological and oceanographic parameters. This issue is investigated by means of statistical tools like EOF- and timeseries analysis, especially Dietmar Dommenget’s rotated DEOFs: a technique which fits a spatial first-order autoregressive ("AR(1)") process as a null hypothesis to the data. These analyses should clarify whether a primary mode of advection exists or whether it is solely the atmospheric imprint on the ocean which generates a sham advection. The findings of SA could partly be confirmed, although a few remarks about the statistical reliability of their analyses are made. Applying an AR(1)-model, which divides its driving noise into a NAO and a non-NAO part, it is shown that the former locally contributes more than 40% to the explained variance of SST variability. The maximum contributions align with the major areas of the NAC, where SA suggest the propagation of SST anomalies. It is shown that this signal is strongly influenced by the atmospheric forcing and that latter generates an advection-like pattern

Ocurrencia de individuos bisexuados y con anomalías en flores y frutos en dos clones de Populus deltoides Marsh. cultivados en la Argentina

p.265-26

Fused-Silica 3D Chiral Metamaterials via Helium-Assisted Microcasting Supporting Topologically Protected Twist Edge Resonances with High Mechanical Quality Factors

It is predicted theoretically that a 1D diatomic chain of 3D chiral cells can support a topological bandgap that allows for translating a small time-harmonic axial movement at one end of the chain into a resonantly enhanced large rotation of an edge state at the other end. This edge state is topologically protected such that an arbitrary mass of a mirror at the other end does not shift the eigenfrequency out of the bandgap. Herein, this complex 3D laser-beam-scanner microstructure is realized in fused-silica form. A novel microcasting approach is introduced that starts from a hollow polymer cast made by standard 3D laser nanoprinting. The cast is evacuated and filled with helium, such that a highly viscous commercial glass slurry is sucked in. After UV curing and thermal debinding of the polymer, the fused-silica glass is sintered at 1225 °C under vacuum. Detailed optical measurements reveal a mechanical quality factor of the twist-edge resonance of 2850 at around 278 kHz resonance frequency under ambient conditions. The microcasting approach can likely be translated to many other glasses, to metals and ceramics, and to complex architectures that are not or not yet amenable to direct 3D laser printing

Abrasive waterjet machining of three-dimensional structures from bulk metallic glasses and comparison with other techniques

Bulk metallic glasses (BMGs) are a promising class of engineering materials, but they can be difficult to machine due to high hardness and a metastable structure. Crystallization due to machining can have negative effects, such as a decreased load-bearing capacity of fabricated parts, and thus should be avoided. Here, a Zr-based BMG was machined using abrasive waterjet (AWJ), electrical discharge, ns-pulsed laser engraving, and conventional dry-milling techniques. Characterization of the processed material indicated that AWJ preserves the amorphous phase and provides the combination of speed and flexibility required to rapidly fabricate small three-dimensional parts, while the other techniques did not achieve these goals. As proof-of-principle, a screw, similar to an orthopedic implant, was rapidly machined from the BMG using AW

Distribution of the putative virulence factor encoding gene sheta in Staphylococcus hyicus strains of various origins

In the present study, Staphylococcus (S.) hyicus strains isolated in Russia (n = 23) and Germany (n = 17) were investigated for the prevalence of the previously described genes sheta and shetb. Sheta was detected in 16 S. hyicus strains. Sheta-positive strains were mainly found among strains isolated from exudative epidermitis, and frequently together with the exfoliative toxin-encoding genes exhD and exhC. Partial sequencing of sheta in a single S. hyicus strain revealed an almost complete match with the sheta sequence obtained from GenBank. None of the S. hyicus strains displayed a positive reaction with the shetb-specific oligonucleotide primer used in the present study. According to the present results, the exotoxin encoding gene sheta seems to be distributed among S. hyicus strains in Russia and Germany. The toxigenic potential of this exotoxin, which does not have the classical structure of a staphylococcal exfoliative toxin, remains to be elucidated

Magazin für digitale Editionswissenschaften : 5 / 2019

Inhalt: Andreas Maier, Daniel Stromer, Vincent Christlein, Peter Bell: Bausteine auf dem Weg zu einer virtuellen Zeitmanschiene – ein Editionsprojekt über lange Dauer Klaus Meyer-Wegener: Semantic Web – Eine kurze Einführung Andreas Kuczera: Mit graphbasierter Edition zur semantischen Multidimensionalität Jörg Wettlaufer: Nachhaltigkeit und Langzeitverfügbarkeit von digitalen Editionen im Semantic We

Optimized seed patterns in cereals

Ein optimiertes Aussaatmuster mit gleichmäßigen Abständen zwischen den Pflanzen erhöht den nutzbaren Stand­raum je Einzelpflanze und reduziert intraspezifische Konkurrenzeffekte. Neben höheren und stabileren Erträgen sind auch Vorteile hinsichtlich Ressourcennutzungseffizienz, Stresstoleranz und Unkrautunterdrückungsvermögen zu erwarten. Aktuell wird Getreide vorwiegend in Drillsaat ausgebracht, was nicht dem pflanzenbaulichen Optimum entspricht, jedoch eine hohe Flächenleistung ermöglicht. Alternativ ist für die Getreideaussaat reihenabhängige Einzelkornsätechnik verfügbar, welche bereits deutliche Vorteile hinsichtlich eines gleichmäßigeren Saatbilds zeigt. Den gleichmäßigsten Standraum je Einzelpflanze erreicht man mit einer Gleichstandsaat im Dreieckverband, welche bei Getreide technisch noch nicht realisierbar ist. Um die erwarteten Vorteile der Gleichstandsaat bei Getreide zu überprüfen, werden am Julius Kühn-Institut Versuche zur Gleichstandsaat bei Winterweizen durchgeführt, um Fragestellungen hinsichtlich Ertrag, Ressourcennutzungseffizienz, Stresstoleranz etc. zu beantworten. Parallel dazu sind die Anpassung einer Einzelkornsämaschine sowie die Entwicklung eines mobilen autonomen Systems geplant, die eine Aussaat im Dreieckverband ermöglichen.An optimized seed pattern with even distances increases the utilizable space of individual plants and reduces intraspecific competition. In addition to higher and more stable yields, benefits in terms of resource use efficiency, stress tolerance and weed suppression are expected. Currently, cereals are mainly sown in rows, which does not corres­pond to the crops’ optimum, but allows a fast sowing. Alternatively, precision seeding is available for cereals, which already allows a more uniform seed pattern. The most even spacing per single plant can be achieved with a uniform seed pattern in a triangular lattice, which is technically not yet feasible in cereals. In order to test the expected benefits of a uniform seed pattern in cereals, field trials are conducted at the JKI with winter wheat to answer questions regarding yield, resource use efficiency and stress tolerance. At the same time, the adaptation of a precision seeding and the development of an autonomous sowing system are planned in order to enable a uniform seed pattern