Intimate mechanical mixtures of various support materials and an amount of MoO3 corresponding to less than a monolayer are calcined at 720 K and the calcined mixtures have been investigated by laser Raman and FTIR spectroscopy.

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reasons have been the low resolving power of the Actin Elaments and microtubules, both in situ and in vitro, were imaged using high-resolution scanning electron microscopy (HRSEM) at low temperature. For visualization of cytoskeletal elements in situ, fibroblasts were first extracted and fixed; for cytoskeletal elements in vitro, purified proteins were polymerized and fixed. Both types of specimen were then subjected to plunge freezing, controlled freeze-drying, cryo-sputter coating with a thin chromium layer, cryo-transferring and cryo-observation in an FESEM. The three-dimensional architecture of the cytoskeleton was well preserved, permitting examination of the structural relationships among cytoskeletal elements. Actin Elaments and microtubules were identified by their characteristic helical features. Two periodicities of actin filaments, the short pitch of the left-handed helix measured at 5-5 nm and the 37-nm-long pitch helix, were revealed.Individual protofilaments were seen in microtubules as well as the characteristic 4-nm repeat of tubulin subunits along the protofilament. Clathrin cages were also observed. This technique provides a powerful approach for direct imaging of macromolecular structures with high contrast and high signal-to-noise ratio at a resolution of 2-3 nm.--

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Differential cross sections for a W boson produced in association with jets are measured in a data sample of proton-proton collisions at a center-of-mass energy of 8 TeV recorded with the CMS detector and corresponding to an integrated luminosity of 19.6 fb −1 . The W bosons are identified through their decay mode W → µν. The cross sections are reported as functions of jet multiplicity, transverse momenta, and the scalar sum of jet transverse momenta (H T ) for different jet multiplicities. Distributions of the angular correlations between the jets and the muon are examined, as well as the average number of jets as a function of H T and as a function of angular variables. The measured differential cross sections are compared with tree-level and higher-order recent event generators, as well as next-to-leading-order and next-tonext-to-leading-order theoretical predictions. The agreement of the generators with the measurements builds confidence in their use for the simulation of W+jets background processes in searches for new physics at the LHC. Published in Physical Review D asEvents are retained if they pass a trigger selection requiring one isolated muon with p T > 24 GeV and |η| < 2.1.Signal and background processes are generated with various state-of-the-art generators and passed through detector simulation based on GEANT4 [14] description of CMS. Each simulated sample is normalized to the integrated luminosity of the data sample. The simulated events are required to pass an emulation of the trigger requirements applied to the data. Trigger efficiencies in the simulation are corrected for differences with respect to the data. Simulations also include additional collisions in the same or adjacent bunch crossings (pileup, PU). To model PU, minimum-bias events generated with PYTHIA6 using the Z2* tune [15] are superimposed on the simulated events, matching the multiplicity of PU collisions observed in data, which has an average value of approximately 21.The W+jets signal process is simulated with the matrix element (ME) generator MADGRAPH 5.1.1 [1] interfaced with PYTHIA 6.426 using the Z2* tune for parton showering and hadronization. This sample of events, denoted MADGRAPH5+PYTHIA6 (denoted as MG5+PY6 in the figure legends), is produced with the CTEQ6L1 parton distribution function (PDF) set [16] √ (∆φ) 2 + (∆η) 2 < 0.4 around the direction of the muon candidate track are considered. The transverse momentum of the muon candidate is denoted by p µ T . Because neutral PU particles deposit on average half as much energy as charged PU particles, the contamination in the isolation cone from neutral particles coming from PU interactions is estimated as 0.5 ∑ PU p T and it is subtracted in the definition of I iso .