Ökologische Bienenhaltung - was zeichnet sie aus?

Unter ökologischer Bienenhaltung ist eine naturnahe, artgemäße Bienenhaltung zu verstehen, die den Grundsätzen der ökologischen Landbewirtschaftung folgt. Ziel der ökologischen Bienenhaltung ist eine hohe Qualität der Imkereiprodukte, die sich dadurch auszeichnen, dass sie unverfälscht sind und eine niedrige Belastung mit Schadstoffen aufweisen. Wie funktioniert ökologische Bienenhaltung, was ist bei ihr anders

Evidence for Cooper Pair Diffraction on the Vortex Lattice of Superconducting Niobium

We investigated the Abrikosov vortex lattice (VL) of a pure Niobium single crystal with the muon spin rotation (\mu SR) technique. Analysis of the \mu SR data in the framework of the BCS-Gor'kov theory allowed us to determine microscopic parameters and the limitations of the theory. With decreasing temperature the field variation around the vortex cores deviates substantially from the predictions of the Ginzburg-Landau theory and adopts a pronounced conical shape. This is evidence of partial diffraction of Cooper pairs on the VL predicted by Delrieu for clean superconductors.Comment: 9 pages, 6 figure

Fluid-melt partitioning of sulfur in differentiated arc magmas and the sulfur yield of explosive volcanic eruptions

The fluid-melt partitioning of sulfur (DSfluid/melt) in differentiated arc magmas has been experimentally investigated under oxidizing conditions (Re-ReO2 buffer) from 800 to 950°C at 200MPa. The starting glasses ranged in composition from trachyte to rhyolite and were synthesized targeting the composition of the residual melt formed after 10-60% crystallization of originally trachy-andesitic, dacitic and rhyodacitic magmas (Masotta and Keppler, 2015). Fluid compositions were determined both by mass balance and by Raman spectroscopy of fluid inclusions. DSfluid/melt increases exponentially with increasing melt differentiation, ranging from 2 to 15 in the trachytic melt, from 20 to 100 in the dacitic and rhyodacitic melts and from 100 to 120 in the rhyolitic melt. The variation of the DSfluid/melt is entirely controlled by the compositional variation of the silicate melt, with temperature having at most a minor effect within the range investigated. Experiments from this study were used together with data from the literature to calibrate the following model that allows predicting DSfluid/melt for oxidized arc magmas: lnDSfluid/melt=9.2-31.4·nbot-1.8·ASI-29.5·Al#+4.2·Ca#where nbot is the non-bridging oxygen atoms per tetrahedron, ASI is the alumina saturation index, Al# and Ca# are two empirical compositional parameters calculated in molar units (Al#=XAl2O3XSiO2+XTiO2+XAl2O3 and Ca#=XCaOXNa2O+XK2O).The interplay between fluid-melt partitioning and anhydrite solubility determines the sulfur distribution among anhydrite, melt and fluid. At increasing melt polymerization, the exponential increase of the partition coefficient and the decrease of anhydrite solubility favor the accumulation of sulfur either in the fluid phase or as anhydrite. On the other hand, the higher anhydrite solubility and lower partition coefficient for less polymerized melts favor the retention of sulfur in the melt. At equilibrium conditions, these effects yield a maximum of the sulfur fraction in the fluid phase for slightly depolymerized melts (nbot= 0.05-0.15). Our data allow quantitative predictions of the sulfur yield of explosive volcanic eruptions over a wide range of magma compositions

Magnetic field distribution and characteristic fields of the vortex lattice for a clean superconducting niobium sample in an external field applied along a three-fold axis

The field distribution in the vortex lattice of a pure niobium single crystal with an external field applied along a three-fold axis has been investigated by the transverse-field muon-spin-rotation (TF-$\mu$SR) technique over a wide range of temperatures and fields. The experimental data have been analyzed with the Delrieu's solution for the form factor supplemented by phenomenological formulas for the parameters. This has enabled us to experimentally establish the temperatures and fields for the Delrieu's, Ginzburg-Landau's, and Klein's regions of the vortex lattice. Using the numerical solution of the quasiclassical Eilenberger's equation the experimental results have been reasonably understood. They should apply to all clean BCS superconductors. The analytical Delrieu's model supplemented by phenomenological formulas for its parameters is found to be reliable for analyzing TF-$\mu$SR experimental data for a substantial part of the mixed phase. The Abrikosov's limit is contained in it.Comment: 12 pages, 15 figure

Legehennen in einem mobilen Stallsystem - Auslaufnutzung und Flächenzustand -

The use of the free-range area by laying hens housed in a mobile system and the resulting condition of the range were investigated. The free-range was used very intensively. On an average of nine complete observation days 35 % of the birds (23 – 44 % means per day) were outside the house. The maximum of animals in the free range was 77 %. 75 % (60 – 95 %) of the hens outside the house stayed in an area of 20 m around the house. This led to deteriorated conditions of the range in these areas. By moving the mobile house regularly (after 2 weeks in summer and 6 weeks in winter) a destruction of the vegetation could be avoided, while after not moving the house for three months in winter a complementary seeding became necessary. We conclude that the use of mobile systems for poultry in conjunction with a regular change of position and sufficient area per animal can avoid destruction of the vegetation despite an intensive use of the free-range all year round

Legehennen in einem mobilen Stallsystem - Flächenmanagement und resultierende Stickstoffgehalte im Auslauf -

In the last years free range poultry was often criticised for its negative impacts on environment. As the animals do not use the run equally, a big part of the excreted nutrients are accumulated in the area close to the poultry house. This can lead to an increased rate of nutrient loss especially nitrogen by leaching. Within this study the use of a mobile housing system for 1.000 layers on an organic farm in North Hessia with a mean of 700 mm precipitation per year and an average of 8,9°C (soil texture: loam in the first, silt loam in the second year) was observed for two years. A documentation and optimization of the management and regular investigations into the contents of mineral nitrogen in all parts of the outdoor run were carried out. The aim of the study was to survey, if a well-balanced distribution of nutrients can be reached by moving the house within the free-range and which management is necessary for that. The results showed a better distribution of mineral nitrogen in the second year, when the house was moved in winter time every six weeks, while the contents were slightly less well-balanced, when it stayed at one position for three months in the first winter . In both years the highest amounts of mineral nitrogen in any part of the hen run with 37 and 24 mg / kg DM were much lower than the contents of up to 160 mg / kg DM close to stationary houses examined in other studies. The results of this study show that a well-balanced distribution of nutrients in free-ranges for poultry can be reached by using mobile housing systems combined with the right management

Synthesis and in vitro Antitumor Potency of (Cyclohexane-1,2-Diamine)Platinum(II) Complexes with Aminotris(Methylenephosphonic Acid) as Bone-Seeking Ligand

In order to develop platinum complexes with selective activity in primary and secondary bone malignancies and with the aim to optimize antitumor activity, platinum(II) complexes with aminotris(methylenephosphonic acid) as bone-seeking (osteotropic) ligand have been synthesized, characterized and tested in the cisplatin-sensitive ovarian carcinoma cell line CH1. As non-leaving diamine ligands, which are decisive for the cellular processing of DNA adducts, cis-R,S-cyclohexane-1,2-diamine, trans-S,S-cyclohexane-1,2-diamine and trans-R,R-cyclohexane-1,2-diamine have been used, resulting in complexes 1, 2, and 3, respectively. The cytotoxicity of the complexes under investigation decreases in the order 3 > 2 > 1 which is in accord with structure-activity relationships with other (cyclohexane-1,2- diamine)platinum(II) and platinum(IV) complexes: Both trans complexes (2 and 3) display a higher in vitro potency than the corresponding cis isomer (I), with the trans-R,R isomer (3) being the most active in this series. In comparison to the analogous (cyclohexane-1,2-diamine)platinum(II) complexes with bis(phosphonomethyl)aminoacetic acid as osteotropic carrier ligand, the cytotoxicity of 1-3 was found to be 1.5 – 2 fold higher, which is explainable by a different coordination mode of the phosphonic acid ligands (acetato versus phosphonato)