2,636 research outputs found

    Entwicklung eines Inkubationssystems fĂŒr ein inverses Mikroskop zur Langzeitbeobachtung von Zellkulturen in gekammerten ObjekttrĂ€gern

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    Trifunctional bispecific antibodies open up new immunological possibilities in tumour treatment. Prior to clinical application, comprehensive investigations using animal models and in vitro examinations need to be done. To investigate long-term interactions between Various immunologically active blood cells and individual tumour cells in the presence of antibodies, we developed an incubation system for experimental cell cultures on an inverted microscope. The system consists of a perspex box with a central moisture chamber with integrated water reservoir, external air circulation heating, and a CO2 supply. The sterile cell cultures are located in the wells of a slide positioned within a depression in the water reservoir. The newly developed incubation system enables continuous observation over the long term of experiments under optimal cell cultures conditions in combination with modern video techniques

    Full spin switch effect for the superconducting current in a superconductor/ferromagnet thin film heterostructure

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    Superconductor/ferromagnet (S/F) proximity effect theory predicts that the superconducting critical temperature of the F1/F2/S or F1/S/F2 trilayers for the parallel orientation of the F1 and F2 magnetizations is smaller than for the antiparallel one. This suggests a possibility of a controlled switching between the superconducting and normal states in the S layer. Here, using the spin switch design F1/F2/S theoretically proposed by Oh et al. [Appl. Phys. Lett. 71, 2376 (1997)], that comprises a ferromagnetic bilayer separated by a non-magnetic metallic spacer layer as a ferromagnetic component, and an ordinary superconductor as the second interface component, we have successfully realized a full spin switch effect for the superconducting current.Comment: 5 pages, 4 figure

    A Combined XPS and Computational Study of the Chemical Reduction of BMP‐TFSI by Lithium

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    Employing density functional theory (DFT) calculations and X-ray photoelectron spectroscopy (XPS), we identify products of the reaction of the ionic liquid N,N-butylmethylpyrrolidinum bis(trifluoromethylsulfonyl)imide (BMP-TFSI) with lithium in order to model the initial chemical processes contributing to the formation of the solid electrolyte interphase in batteries. Besides lithium oxide, sulfide, carbide and fluoride, we find lithium cyanide or cyanamide as possible, thermodynamically stable product in the Li-poor regime, whilst Li3_{3}N is the stable product in the Li-rich regime. The thermodynamically controlled reaction products as well as larger fragments of TFSI persisting due to kinetic barriers could be identified by a comparison of experimentally and computationally determined core level binding energies

    X-ray bolometric corrections for Compton-thick active galactic nuclei

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    We present X-ray bolometric correction factors, ÎșBol\kappa_{Bol} (≡LBol/LX\equiv L_{Bol}/L_X), for Compton-thick (CT) active galactic nuclei (AGN) with the aim of testing AGN torus models, probing orientation effects, and estimating the bolometric output of the most obscured AGN. We adopt bolometric luminosities, LBolL_{Bol}, from literature infrared (IR) torus modeling and compile published intrinsic 2--10 keV X-ray luminosities, LXL_{X}, from X-ray torus modeling of NuSTAR data. Our sample consists of 10 local CT AGN where both of these estimates are available. We test for systematic differences in ÎșBol\kappa_{Bol} values produced when using two widely used IR torus models and two widely used X-ray torus models, finding consistency within the uncertainties. We find that the mean ÎșBol\kappa_{Bol} of our sample in the range LBol≈1042−1045L_{Bol}\approx10^{42}-10^{45} erg/s is log10ÎșBol=1.44±0.12_{10}\kappa_{Bol}=1.44\pm0.12 with an intrinsic scatter of ∌0.2\sim0.2 dex, and that our derived ÎșBol\kappa_{Bol} values are consistent with previously established relationships between ÎșBol\kappa_{Bol} and LBolL_{Bol} and ÎșBol\kappa_{Bol} and Eddington ratio. We investigate if ÎșBol\kappa_{Bol} is dependent on NHN_H by comparing our results on CT AGN to published results on less-obscured AGN, finding no significant dependence. Since many of our sample are megamaser AGN, known to be viewed edge-on, and furthermore under the assumptions of AGN unification whereby unobscured AGN are viewed face-on, our result implies that the X-ray emitting corona is not strongly anisotropic. Finally, we present ÎșBol\kappa_{Bol} values for CT AGN identified in X-ray surveys as a function of their observed LXL_X, where an estimate of their intrinsic LXL_{X} is not available, and redshift, useful for estimating the bolometric output of the most obscured AGN across cosmic time.Comment: Accepted for publication in Ap

    SPIDERS: Selection of spectroscopic targets using AGN candidates detected in all-sky X-ray surveys

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    SPIDERS (SPectroscopic IDentification of eROSITA Sources) is an SDSS-IV survey running in parallel to the eBOSS cosmology project. SPIDERS will obtain optical spectroscopy for large numbers of X-ray-selected AGN and galaxy cluster members detected in wide area eROSITA, XMM-Newton and ROSAT surveys. We describe the methods used to choose spectroscopic targets for two sub-programmes of SPIDERS: X-ray selected AGN candidates detected in the ROSAT All Sky and the XMM-Newton Slew surveys. We have exploited a Bayesian cross-matching algorithm, guided by priors based on mid-IR colour-magnitude information from the WISE survey, to select the most probable optical counterpart to each X-ray detection. We empirically demonstrate the high fidelity of our counterpart selection method using a reference sample of bright well-localised X-ray sources collated from XMM-Newton, Chandra and Swift-XRT serendipitous catalogues, and also by examining blank-sky locations. We describe the down-selection steps which resulted in the final set of SPIDERS-AGN targets put forward for spectroscopy within the eBOSS/TDSS/SPIDERS survey, and present catalogues of these targets. We also present catalogues of ~12000 ROSAT and ~1500 XMM-Newton Slew survey sources which have existing optical spectroscopy from SDSS-DR12, including the results of our visual inspections. On completion of the SPIDERS program, we expect to have collected homogeneous spectroscopic redshift information over a footprint of ~7500 deg2^2 for >85 percent of the ROSAT and XMM-Newton Slew survey sources having optical counterparts in the magnitude range 17<r<22.5, producing a large and highly complete sample of bright X-ray-selected AGN suitable for statistical studies of AGN evolution and clustering.Comment: MNRAS, accepte
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