Bladsygdomme på byg afhænger af sort, placering i sædskiftet og gødningstype

Plantesygdomme i økologisk planteproduktion har stor indflydelse på produktkvalitet og udbytte. Specielt i korn er der gode muligheder for at forebygge svampesygdomme ved hjælp af sortsresistens, idet mange års planteforædling har bidraget til at øge niveauet af resistens mod de mest betydende svampesygdomme. Dette gælder bl.a. resistens mod bladsvampe som meldug, bygrust, skoldplet og forskellige bladpletsvampe. En sorts resistensniveau mod en given svampesygdom er imidlertid ikke konstant, men kan ændre sig over tid og have forskellig effekt i forskellige dele af landet. Det skyldes primært forskelle og dynamik i de patogenpopulationer, som forårsager de pågældende sygdomme. Derudover er sygdomsniveauet i den enkelte mark afhængig af det lokale smittetryk i begyndelsen af vækstsæsonen, jordens næringsstofbalance- og frigivelse, mikrobiel aktivitet samt vind og vejr

The phonon dispersion of graphite by inelastic x-ray scattering

We present the full in-plane phonon dispersion of graphite obtained from inelastic x-ray scattering, including the optical and acoustic branches, as well as the mid-frequency range between the $K$ and $M$ points in the Brillouin zone, where experimental data have been unavailable so far. The existence of a Kohn anomaly at the $K$ point is further supported. We fit a fifth-nearest neighbour force-constants model to the experimental data, making improved force-constants calculations of the phonon dispersion in both graphite and carbon nanotubes available.Comment: 7 pages; submitted to Phys. Rev.

Boundary effects in finite size plasmonic crystals: Focusing and routing of plasmonic beams for optical communications

Plasmonic crystals, which consist of periodic arrangements of surface features at a metal-dielectric interface, allow the manipulation of optical information in the form of surface plasmon polaritons. Here we investigate the excitation and propagation of plasmonic beams in and around finite size plasmonic crystals at telecom wavelengths, highlighting the effects of the crystal boundary shape and illumination conditions. Significant differences in broad plasmonic beam generation by crystals of different shapes are demonstrated, while for narrow beams, the propagation onto the smooth metal film is less sensitive to the crystal boundary shape. We show that by controlling the boundary shape, the size and the excitation beam parameters, directional control of propagating plasmonic modes and associated beam parameters such as angular beam splitting, focusing power and beam width can be efficiently achieved. This provides a promising route for robust and alignment-independent integration of plasmonic crystals with optical communication components

The Distance to the Coma Cluster from Surface Brightness Fluctuations

We report on the first determination of the distance to the Coma Cluster based on surface brightness fluctuation (SBF) measurements obtained from Hubble Space Telescope WFPC2 observations of the bright E0 galaxy NGC 4881 in the Coma Cluster and ground-based observations of the standard E1 galaxy NGC 3379 in the Leo-I group. Relative distances based on the I-band fluctuation magnitude, I(SBF), are strongly dependent on metallicity and age of the stellar population. However, the radial changes in the stellar populations of the two giant ellipticals, NGC 3379 and NGC 4881, are well described by published Mg_2 gradients, and the ground-based measurements of I(SBF) at several radial points in NGC 3379 are used to calibrate I(SBF) in terms of the Mg_2 index. The distance to NGC 3379, assumed to be identical to the average SBF distance of the Leo-I group, is combined with the new SBF measurements of NGC 4881 to obtain a Coma Cluster distance of 102+-14 Mpc. Combining this distance with the cosmic recession velocity of Coma (7186+-428 km/s), we find the Hubble constant to be H_0 = 71+-11 km/s/Mpc.Comment: 12 pages, LaTex, includes aaspp4.sty and 3 eps figures. To appear in ApJ Letter

Metformin and other glucose-lowering drug initiation and rates of community-based antibiotic use and hospital-treated infections in patients with type 2 diabetes: a Danish nationwide population-based cohort study

OBJECTIVE: Data on early risk of infection in patients receiving their first treatment for type 2 diabetes are limited. We examined rates of community-based antibiotic use and hospital-treated infection in initiators of metformin and other glucose-lowering drugs (GLDs). DESIGN: Population-based cohort study using medical databases. SETTING: General practice and hospitals in Denmark. PARTICIPANTS: 131 949 patients with type 2 diabetes who initiated pharmacotherapy with a GLD between 2005 and 2012. EXPOSURE: Initial GLD used for pharmacotherapy. MAIN OUTCOME MEASURES: We computed rates and adjusted HRs of community-based antibiotic use and hospital-treated infection associated with choice of initial GLD with reference to metformin initiation, using an intention-to-treat approach. RESULTS: The rate of community-based antibiotic use was 362 per 1000 patient-years at risk (PYAR) and that for hospital-treated infection was 51 per 1000 PYAR. Compared with metformin, the risk of hospital-treated infection was slightly higher in sulfonylurea initiators (HR 1.12, 95% CI 1.08 to 1.16) and substantially higher in insulin initiators (HR 1.63, 95% CI 1.54 to 1.72) initiators after adjustment for comorbid conditions, comedications and other confounding factors. In contrast, virtually no difference was observed for overall community-based antibiotic use (HR 1.02, 95% CI 1.01 to 1.04, for sulfonylurea initiators; and 1.04, 95% CI 1.01 to 1.07, for insulin initiators). CONCLUSIONS: Rates of community-based antibiotic treatment and hospitalisation for infection were high in patients receiving their first treatment for type 2 diabetes and differed with the choice of initial GLD used for pharmacotherapy

The benthic foraminiferal community in a naturally CO2-rich coastal habitat in the southwestern Baltic Sea

It is expected that the calcification of foraminifera will be negatively affected by the ongoing acidification of the oceans. Compared to the open oceans, these organisms are subjected to much more adverse carbonate system conditions in coastal and estuarine environments such as the southwestern Baltic Sea, where benthic foraminifera are abundant. This study documents the seasonal changes of carbonate chemistry and the ensuing response of the foraminiferal community with bi-monthly resolution in Flensburg Fjord. In comparison to the surface pCO2, which is close to equilibrium with the atmosphere, we observed large seasonal fluctuations of pCO2 in the bottom and sediment pore waters. The sediment pore water pCO2 was constantly high during the entire year ranging from 1244 to 3324 μatm. Nevertheless, in contrast to the bottom water, sediment pore water was slightly supersaturated with respect to calcite as consequence of higher alkalinity (AT) for the most time of the year. Foraminiferal assemblages were dominated by two calcareous species, Ammonia aomoriensis and Elphidium incertum, and the agglutinated Ammotium cassis. The one year-cycle was characterized by seasonal community shifts. Our results revealed that there is no dynamic response of foraminiferal population density and diversity to elevated sediment pore water pCO2. Surprisingly, the fluctuations of sediment pore water undersaturation (Ωcalc) co-vary with the population densities of living Ammonia aomoriensis. Further, we observed that most of the tests of living calcifying specimens were intact. Only Ammonia aomorienis showed dissolution and recalcification structures on the tests, especially at undersaturated conditions. Therefore, the benthic community is subjected to constantly high pCO2 and tolerates elevated levels as long as sediment pore water remains supersaturated. Model calculations inferred that increasing atmospheric CO2 concentrations will finally lead to a perennial undersaturation in sediment pore waters. Whereas benthic foraminifera indeed may cope with a high sediment pore water pCO2, the steady undersaturation of sediment pore waters would likely cause a significant higher mortality of the dominating Ammonia aomoriensis. This shift may eventually lead to changes in the benthic foraminiferal communities in Flensburg Fjord, as well as in other regions experiencing naturally undersaturated Ωcalc levels

Techniques to improve technological and sanitary quality

Agronomical ways for better quality and safety Choice of cultivar is an efficient way to obtain higher grain quality. Intercropping legumes (grain or forage) improves weed competition and N availability for wheat crop or succeeding crop. Green manure can be an effective alternative to farmyard manure. Fertilization with readily available nitrogen improves yield and quality when water is available. Reduced tillage affects soil fertility and wheat yield but has little effects on grain quality. Technological ways for better quality and safety Milling process strongly influences flour characteristics. Stone milling improves nutritive value; characteristics remain very stable independent of the milling yield. Flour characteristics from roller milling appear very susceptible to the milling yield. Increasing the milling yield in the aim of enriching nutritional quality has a detrimental effect either on safety (DON) or on bread-making quality (bread volume)

Technological quality of organic wheat in Europe

The demand for high quality organic bread wheat is increasing. The quality level of organic wheat harvested in EU is mainly dependant on variety, environmental conditions and agronomic practices. In some countries, protein content and composition, influencing technological value, are equivalent to those produced under conventional practices. Beside agronomical techniques, technological processes can help to maintain a good quality. Pre-treatments before milling such as debranning were found to be efficient in reducing DON contamination. The project highlighted the necessity to redefine the methods to assess the quality of organic wheat

Burial depth and post-Early Cretaceous uplift of Lower–Middle Jurassic strata in the Fennoscandian Border Zone based on organic maturity

The burial depth and the magnitude of Late Cretaceous – Early Cenozoic and Neogene–Pleistocene uplift of Lower–Middle Jurassic strata in the Fennoscandian Border Zone are estimated from measurements of huminite reflectance and comparison with a regional coalification gradient. The regional coalification curve is constructed by plotting uplift-corrected sample depths against more than 300 huminite/vitrinite reflectance values from Upper Triassic – Lower Cretaceous deposits in the Danish Basin and the Fennoscandian Border Zone. The present sample depths are corrected for Late Cretaceous inversion in the Sorgenfrei–Tornquist Zone and for Neogene–Pleistocene regional uplift. A coalification curve is erected; it cuts the abscissa at 0.2 %Ro corresponding to the reflectance of peat. This curve is considered to approximate to a reliable coalification profile over much of the study area. The Jurassic coals from the Fennoscandian Border Zone are of low rank and, based on the regional coalification curve, they have been buried to c. 625–2450 m. In the eastern part of the Rønne Graben, in the Kolobrzeg Graben and in the Arnager–Sose Fault Block, the Jurassic strata were subsequently uplifted c. 290–1400 m, corresponding to the amount of Late Cretaceous – Early Cenozoic inversion observed on seismic sections. Thus, it appears that Neogene–Pleistocene uplift did not influence the Bornholm area significantly. The data from the Höganäs Basin and Fyledal indicate a total uplift of c. 1450–2450 m, corresponding to estimates from the inversion zone in the Kattegat. The data from Anholt, on the eastern margin of the inversion zone, indicate c. 975 m of uplift