Crystal and magnetic structure of substituted lanthanum cobaltites

The crystal and magnetic structures of the lanthanum cobaltites La0.6Sr0.4CoO3, La0.6Sr0.4Co0.9Fe0.1O3 and La0.6Ba0.4Co0.9Fe0.1O3 have been studied by neutron powder diffraction at temperatures of 2, 300 and 900 K. All compounds undergo a phase transition from cubic to rhombohedral structure. Below the room temperature La0.6Sr0.4CoO3 becomes ferromagnetic while for the components with 10% Fe substituted for Co, we found an antiferromagnetic order

Bootstrap approximation for the exchange-correlation kernel of time-dependent density functional theory

A new parameter-free approximation for the exchange-correlation kernel $f_{\rm xc}$ of time-dependent density functional theory is proposed. This kernel is expressed as an algorithm in which the exact Dyson equation for the response as well as a further approximate condition are solved together self-consistently leading to a simple parameter-free kernel. We apply this to the calculation of optical spectra for various small bandgap (Ge, Si, GaAs, AlN, TiO$_2$, SiC), large bandgap (C, LiF, Ar, Ne) and magnetic (NiO) insulators. The calculated spectra are in very good agreement with experiment for this diverse set of materials, highlighting the universal applicability of the new kernel.Comment: 4 figures 5 page

Fabrication of comb-drive actuators for straining nanostructured suspended graphene

We report on the fabrication and characterization of an optimized comb-drive actuator design for strain-dependent transport measurements on suspended graphene. We fabricate devices from highly p-doped silicon using deep reactive ion etching with a chromium mask. Crucially, we implement a gold layer to reduce the device resistance from $\approx51.6$ k$\mathrm{\Omega}$ to $\approx236$ $\mathrm{\Omega}$ at room temperature in order to allow for strain-dependent transport measurements. The graphene is integrated by mechanically transferring it directly onto the actuator using a polymethylmethacrylate membrane. Importantly, the integrated graphene can be nanostructured afterwards to optimize device functionality. The minimum feature size of the structured suspended graphene is 30 nm, which allows for interesting device concepts such as mechanically-tunable nanoconstrictions. Finally, we characterize the fabricated devices by measuring the Raman spectrum as well as the a mechanical resonance frequency of an integrated graphene sheet for different strain values.Comment: 10 pages, 9 figure

Steroid concentrations in atopic dermatitis patients: Reduced plasma DHEAS and increased cortisone levels.

Atopic dermatitis (AD) is a chronically relapsing inflammatory skin disease, which is characterized by a disrupted epidermal barrier function present both in affected skin and in non-affected skin. Mainly glucocorticosteroids were used in topical and systemic atopy treatments because of their potent anti-inflammatory effects, unfortunately with strong side effects. In this study we determined that 2 out of 16 steroids were significantly different in healthy volunteers vs AD-patients. Cortisone, which is higher in AD-patients plasma, is a direct precursor of the bioactive corticosteroid cortisol, which just displays a higher tendency and is known for its potent anti-inflammatory effects. In addition a tendency of reduced levels of the anti-inflammatory ER ligand estrone was found in AD-patients. DHEA is a precursor of testosterone, its levels just display a lower tendency in male AD-patients, while its sulfonation metabolite DHEAS is lower in male and female AD-patients. We found and conclude that altered steroid levels in the plasma of AD-patients indicate altered vitamin D signaling (based on reduced DHEA sulfonation) and increased feedback for anti-inflammatory signaling (increased levels of cortisone) present in AD-patients. This article is protected by copyright. All rights reserved

Economics of alternative input use and crop diversity strategies in the Dark Brown Soil Zone of Saskatchewan

Non-Peer Reviewe

Effects of input level and crop diversity on energy use efficiency of cropping systems in the Dark Brown Soil Zone

Non-Peer Reviewe

Objective Function Development Based on the Parameters of a Regional Terminal Network

The article is devoted to the development of the objective function for calculating the parameters of a terminal network in a region. The key parameters of a terminal network, as logistic system, are described. The factors influencing the parameters of a terminal network are analyzed, and the objective function, concerning the value and qualitative aspects for determining the transport and spatial/quantitative parameters proposed. The level of service quality for the clients is also taken into account. The heuristic solution method, and the results of the approach are demonstrated with the help of an application example concerning different combinations of distribution.Der Artikel widmet sich der Modellierung eines Transportnetzes, das, unter Beachtung der Lage der Distributionszentren und der Lage der Kunden, minimale Gesamtlogistikkosten ergibt. Diese setzen sich wiederum aus den Transport- und aus den Standortkosten hinsichtlich der Lager- und Betriebskosten der Distributionszentren zusammen. Darüber hinaus wird auch die Maximierung beziehungsweise das Niveau der Servicequalität für die Kunden einbezogen. Das heuristische Lösungsverfahren wird anschließend an einem Anwendungsbeispiel hinsichtlich unterschiedlicher Kombinationen von Distributionszentren erprobt und hinsichtlich der Zielerreichung dokumentiert