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The reversible phosphorylation of proteins on serine, threonine, and tyrosine residues is an important biological regulatory mechanism. In the context of genome integrity, signaling cascades driven by phosphorylation are crucial for the coordination and regulation of DNA repair. The two serine/threonine protein kinases ataxia telangiectasia-mutated (ATM) and Ataxia telangiectasia-mutated and Rad3-related (ATR) are key factors in this process, each specific for different kinds of DNA lesions. They are conserved across eukaryotes, mediating the activation of cell-cycle checkpoints, chromatin modifications, and regulation of DNA repair proteins. We designed a novel mass spectrometry-based phosphoproteomics approach to study DNA damage repair in Arabidopsis thaliana.The protocol combines filter aided sample preparation, immobilized metal affinity chromatography, metal oxide affinity chromatography, and strong cation exchange chromatography for phosphopeptide generation, enrichment, and separation. Isobaric labeling employing iTRAQ (isobaric tags for relative and absolute quantitation) was used for profiling the phosphoproteome of atm atrdouble mutants and wild type plants under either regular growth conditions or challenged by irradiation. A total of 10,831 proteins were identified and 15,445 unique phosphopeptides were quantified, containing 134 up- and 38 down-regulated ATM/ATR dependent phosphopeptides. We identified known and novel ATM/ATR targets such as LIG4 and MRE11 (needed for resistance against ionizing radiation), PIE1 and SDG26 (implicated in chromatin remodeling), PCNA1, WAPL, and PDS5 (implicated in DNA replication), and ASK1 and HTA10 (involved in meiosis).

Redox gold(I)/gold(III) catalytic cycles have been proposed as the productive mechanistic manifold in a number of gold mediated C–C and C–X bond forming reactions. These transformations rely on the use of stoichiometric oxidants such as iodonium salts and Selectfluor. We have studied the oxidation of electron deficient [Au(C6F5)(PPh3)] (1) in the presence of such oxidizing agents. The reaction of 1with PhI(OAc)2afforded cis‐[Au(C6F5)2Cl(PPh3)] (3), which seemed to be produced by oxidation of the starting complex followed by a gold(I)/gold(III) transmetalation process or ligand exchange. The reaction of 1with Selectfluor afforded an unprecedented gold(I)–gold(III) complex [Au(PPh3)2][Au(C6F5)4] (7).

In this work nanostructures based on a 30 nm thick 3C-SiC (100) heteroepitaxially grown on Si(100) are demonstrated. They consist of free standing nanoresonators with dimensions below 50 nm. The free standing nanostructures and resonators were defined by electron beam lithography using hydrogen silsesquioxane (HSQ) as a negative tone e-beam resist acting as a selective etching mask during the anisotropic and isotropic dry etching. The influences of the proximity effect, the crystallographic orientation, the angle of exposing on the feature size are highlighted.

A multi-camera network is proposed to estimate an aircraft’s motion parameters relative to the reference platform in large outdoor fields. Multiple cameras are arranged to cover the aircraft’s large-scale motion spaces by field stitching. A camera calibration method using dynamic control points created by a multirotor unmanned aerial vehicle is presented under the conditions that the field of view of the cameras is void. The relative deformation of the camera network caused by external environmental factors is measured and compensated using a combination of cameras and laser rangefinders. A series of field experiments have been carried out using a fixed-wing aircraft without artificial makers, and its accuracy is evaluated using an onboard Differential Global Positioning System. The experimental results show that the multi-camera network is precise, robust, and highly dynamic and can improve the aircraft’s landing accuracy.