Contrasting Phenomenology of NMR Shifts in Cuprate Superconductors

Nuclear magnetic resonance (NMR) shifts, if stripped off their uncertainties, must hold key information about the electronic fluid in the cuprates. The early shift interpretation that favored a single-fluid scenario will be reviewed, as well as recent experiments that reported its failure. Thereafter, based on literature shift data for planar Cu a contrasting shift phenomenology for cuprate superconductors is developed, which is very different from the early view while being in agreement with all published data. For example, it will be shown that the hitherto used hyperfine scenario is inadequate as a large isotropic shift component is discovered. Furthermore, the changes of the temperature dependences of the shifts above and below the superconducting transitions temperature proceed according to a few rules that were not discussed before. It appears that there can be substantial spin shift at the lowest temperature if the magnetic field lies in the CuO$_2$ plane, which points to a localization of spin in the $3d(x^2-y^2)$ orbital. A simple model is presented based on the most fundamental findings. The analysis must have new consequences for theory of the cuprates

Strategien zur Regulierung der Ackerkratzdistel (Cirsium arvense) im Ökologischen Landbau

The field experiment compared two means of soil tillage and examined the response of grain yield of cultivated cereals and population density of Canada thistle. Results suggest that in fields with a marked proliferation soil tillage cannot be expected to considerably reduce Canada thistle. Besides, the data from the first two seasons indicate a significantly lower or comparable grain yield of cereals after reduced tillage

Studien zur Lokalisation: Teil: 3. Raum und Grammatik oder: Wie berechenbar ist Sprache? ; [Darin enthalten: Hasase, Martin: Parameters of spatial orientation]

Gegenstand dieses Aufsatzes ist das Verhältnis zwischen der Wahrnehmung einer Anordnung im Raum und der Kategorisierung grammatischer Information. Bei der Diskussion unterschiedlicher Ansätze zu diesem Thema (Metapherntheorie , Gestalttheorie u.a.) stehen die Fragen nach der Existenzberechtigung und dem Erklärungspotential eines lokalistischen Ansatzes im Vordergrund. Während eine direkte Beziehung zwischen räumlicher und grammatischer Kategorisierung abzulehnen ist, liegt ein gemeinsamer Nenner in übergreifenden Prinzipien der Mustererkennung. In einer Theorie der Mustererkennung "vereinen sich wesentliche Gedanken aus Wahrnehmungs- und Lernbarkeitstheorien und deren Formulierung mittels "berechenbarer" geometrisch-topologischer Modelle. Als Illustration dienen u.a. Beispiele zur Kasusmarkierung und zur sprachlichen Kategorisierung von Aspekt und Tempus

Investigation of room temperature multispin-assisted bulk diamond 13C hyperpolarization at low magnetic fields

In this work we investigated the time behavior of the polarization of bulk 13C nuclei in diamond above the thermal equilibrium. This nonthermal nuclear hyperpolarization is achieved by cross relaxation between two nitrogen related paramagnetic defect species in diamond in combination with optical pumping. The decay of the hyperpolarization at four different magnetic fields is measured. Furthermore, we use the comparison with conventional nuclear resonance measurements to identify the involved distances of the nuclear spin with respect to the defects and therefore the coupling strengths. Also, a careful look at the linewidth of the signal give valuable information to piece together the puzzle of the hyperpolarization mechanism

Coordinates and maps of the Apollo 17 landing site

We carried out an extensive cartographic analysis of the Apollo 17 landing site and determined and mapped positions of the astronauts, their equipment, and lunar landmarks with accuracies of better than ±1 m in most cases. To determine coordinates in a lunar body‐fixed coordinate frame, we applied least squares (2‐D) network adjustments to angular measurements made in astronaut imagery (Hasselblad frames). The measured angular networks were accurately tied to lunar landmarks provided by a 0.5 m/pixel, controlled Lunar Reconnaissance Orbiter Camera (LROC) Narrow Angle Camera (NAC) orthomosaic of the entire Taurus‐Littrow Valley. Furthermore, by applying triangulation on measurements made in Hasselblad frames providing stereo views, we were able to relate individual instruments of the Apollo Lunar Surface Experiment Package (ALSEP) to specific features captured in LROC imagery and, also, to determine coordinates of astronaut equipment or other surface features not captured in the orbital images, for example, the deployed geophones and Explosive Packages (EPs) of the Lunar Seismic Profiling Experiment (LSPE) or the Lunar Roving Vehicle (LRV) at major sampling stops. Our results were integrated into a new LROC NAC‐based Apollo 17 Traverse Map and also used to generate a series of large‐scale maps of all nine traverse stations and of the ALSEP area. In addition, we provide crater measurements, profiles of the navigated traverse paths, and improved ranges of the sources and receivers of the active seismic experiment LSPE

Influence of Reduced Tillage and Green Manures on Weed Emergence and Yield in Organic Farming (TILMAN-ORG SESSION)

If farmers want to use reduced tillage in organic agriculture, they often face great challenges in weed control. One goal of the European research project TILMAN ORG (www.tilman-org.net) was to develop a more efficient weed management and increased biodiversity through improved use of green manures in different systems of reduced tillage. In a repeated one year trial on the research farm of University of Kassel the effects of different green manure species and different tillage systems on weed cover, density and biomass as well as yield of a subsequent main crop were examined. Sinapis alba, Trifolium resupinatum and Vicia sativa were tested as green manure species. Bare fallow served as control. After the green manures the main crop oat was sown in four different tillage systems: (1) plough, (2) chisel (2011/12) or disc harrow (2012/13), (3) mulching + drilling and (4) direct drilling. In 2011/12, weed cover was generally low in the plough system compared to the other tillage systems. In the mulching + drilling- and direct drilling- systems V. sativa was able to suppress weeds considerably more efficiently than the other green manure treatments. The oat plots after the green manure species S. alba and T. resupinatum as well as the bare fallow had to be given up because weed pressure was too high. Instead, the oat yield in the mulching + drilling- and direct drilling treatments after green manure species V. sativa resulted in oat yields similar to the plough treatments. In the chisel system, oat yield in the V. sativa treatment was significantly higher than in the other green manure treatments. 2012/13 all mulching + drilling- and direct drilling- plots had to be given up because of too high weed pressure. In the disc harrow– system weed pressure differed not significantly from the plough system, but only green manure species V. sativa resulted in comparable oat yields