RESI: Thermal neutron single crystal diffractometer

The diffractometer RESI, which is operated by the Department für Geo- und Umweltwissenschaften Sektion Kristallographie, Ludwig-Maximilians-Universität München and the Technische Universität München, is designed for high q-resolution, low background and best flux usage allowing optimum measurements of weak diffraction phenomena in a large portion of the reciprocal space on single crystalline samples

Initiating Heavy-atom Based Phasing by Multi-Dimensional Molecular Replacement

To obtain an electron-density map from a macromolecular crystal the phase-problem needs to be solved, which often involves the use of heavy-atom derivative crystals and concomitantly the determination of the heavy atom substructure. This is customarily done by direct methods or Patterson-based approaches, which however may fail when only poorly diffracting derivative crystals are available, as often the case for e.g. membrane proteins. Here we present an approach for heavy atom site identification based on a Molecular Replacement Parameter Matrix (MRPM) search. It involves an n-dimensional search to test a wide spectrum of molecular replacement parameters, such as clusters of different conformations. The result is scored by the ability to identify heavy-atom positions, from anomalous difference Fourier maps, that allow meaningful phases to be determined. The strategy was successfully applied in the determination of a membrane protein structure, the CopA Cu+-ATPase, when other methods had failed to resolve the heavy atom substructure. MRPM is particularly suited for proteins undergoing large conformational changes where multiple search models should be generated, and it enables the identification of weak but correct molecular replacement solutions with maximum contrast to prime experimental phasing efforts.Comment: 19 pages total, main paper: 6 pages (2 figures), supplementary material: 13 pages (2 figures, 9 tabels

Muscle mitochondrial function in patients with type 2 diabetes mellitus and peripheral arterial disease: implications in vascular surgery

AbstractObjectives(1) To review the available information on mitochondrial function in type 2 diabetes mellitus (T2DM) and peripheral arterial disease (PAD) obtained by non-invasive phosphor magnetic resonance spectroscopy (31PMRS), near-infrared spectroscopy (NIRS) in vivo and respirometry on mitochondria isolated from muscle biopsies in vitro (2) to evaluate the usefulness of such data in the diagnosis, treatment and prognosis of these patients.DesignReview.MethodsSearch strategy: PubMed (http://www.ncbi.nlm.nih.gov/PubMed) and manual literature search.Main resultsFifty-three articles were retrieved, which included 31PMRS, 15, NIRS, 11, Combined, 1 and Respirometry, 2 and background literature, 24.ConclusionMuscle mitochondrial function is impaired in both T2DM and PAD patients, but differently. Patients suffering from both pathological conditions will display more serious impairment of the mitochondrial function. Mitochondrial function and the degree of ischaemic disease as evaluated by 31PMRS and NIRS are well correlated. The NIRS technique appears to determine the degree of PAD better than 31PMRS. It is argued that systematic testing of mitochondrial function may be a useful prognostic tool with PAD and T2DM, but clinical studies are needed

Antarctic krill and ecosystem monitoring survey off the South Orkney islands in 2018

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Antarctic krill and ecosystem monitoring survey off the South Orkney Islands in 2018

Environmental monitoring along set transect lines off South Orkney Islands, Southern Ocean. Executed annual surveys (since 2011) to collect acoustic and biological data on krill, other macro zooplankton and data on krill predators from sector 48.2 in the Southern Ocean.publishedVersio