Crystal Structure Of (3e)-3-[(4-nitrophenoxy) Methyl]-4-phenylbut-3-en-2-one

In the title compound, C17H15NO4, the conformation about the C=C double bond [1.348(2)Å] is E with the ketone group almost co-planar [C-C-C-C torsion angle = 7.2(2)°] but the phenyl group twisted away [C-C-C-C = 160.93(17)°]. The terminal aromatic rings are almost perpendicular to each other [dihedral angle = 81.61(9)°] giving the molecule an overall U-shape. The crystal packing feature benzene-C-H⋯O(ketone) contacts that lead to supramolecular helical chains along the b axis. These are connected by π-π interactions between benzene and phenyl rings [inter-centroid distance = 3.6648(14)Å], resulting in the formation of a supramolecular layer in the bc plane.709o1020o1021Altomare, A., Burla, M.C., Camalli, M., Cascarano, G.L., Giacovazzo, C., Guagliardi, A., Moliterni, A.G.G., Spagna, R., (1999) J. Appl. Cryst32, pp. 115-119Brandenburg, K., (2006) DIAMOND, , Crystal Impact GbR, Bonn, Germany(2009) APEX2 and SAINT, , Bruker Bruker AXS Inc., Madison, Wisconsin, USA(2010) Marvinsketch, , http://www.chemaxon.com, ChemaxonFarrugia, L.J., (2012) J. Appl. Cryst45, pp. 849-854De Paula, B.R.S., Zampieri, D.S., Rodrigues, J.A.R., Moran, P.J.S., (2013) Tetrahedron: Asymmetry24, pp. 973-981Rodrigues, J.A.R., Moran, P.J.S., Conceicaõ, G.J.A., Fardelone, L.C., (2004) Food Technol. Biotechnol42, pp. 295-303Sheldrick, G.M., (1996) SADABS, , University of Göttingen, GermanySheldrick, G.M., (2008) Acta Cryst A64, pp. 112-122Westrip, S.P., (2010) J. Appl. Cryst43, pp. 920-92

Magnetobiostratigraphic Synthesis of Leg 123: Sites 765 and 766 (Argo Abyssal Plain and Lower Exmouth Plateau)

During ODP Leg 123, Sites 765 and 766 were drilled to examine the tectonic evolution, sedimentary history, and paleoceanography of the Argo Abyssal Plain and lower Exmouth Plateau. At each site, the quality of magnetostratigraphic and biostratigraphic records varies because of complicating factors, such as the predominance of turbidites, the presence of condensed horizons, or deposition beneath the CCD. Based primarily on the presence of nannofossils, the base of the sedimentary section at Site 765 was dated as Tithonian. A complete Cretaceous sequence was recovered at this site, although the sedimentation rate varies markedly through the section. The Cretaceous/Tertiary boundary is represented by a condensed horizon. The condensed Cenozoic sequence at Site 765 extends from the upper Paleocene to the lower Miocene. A dramatic increase in sedimentation rate was observed in the lower Miocene, and a 480-m-thick Neogene section is present. The Neogene section is continuous, except for a minor hiatus in the lower Pliocene. The base of the sedimentary section at Site 766 is Valanginian, in agreement with the site's position on marine magnetic anomaly Mil. Valanginian to Barremian sediments are terrigenous, with variable preservation of microfossils, and younger sediments are pelagic, with abundant well-preserved microfossils. Sedimentation rate is highest in the Lower Cretaceous and decreases continually upsection. Upper Cenozoic sediments are condensed, with several hiatuses

Radiation damage in the LHCb vertex locator

The LHCb Vertex Locator (VELO) is a silicon strip detector designed to reconstruct charged particle trajectories and vertices produced at the LHCb interaction region. During the first two years of data collection, the 84 VELO sensors have been exposed to a range of fluences up to a maximum value of approximately 45 × 1012 1 MeV neutron equivalent (1 MeV neq). At the operational sensor temperature of approximately −7 °C, the average rate of sensor current increase is 18 μA per fb−1, in excellent agreement with predictions. The silicon effective bandgap has been determined using current versus temperature scan data after irradiation, with an average value of Eg = 1.16±0.03±0.04 eV obtained. The first observation of n+-on-n sensor type inversion at the LHC has been made, occurring at a fluence of around 15 × 1012 of 1 MeV neq. The only n+-on-p sensors in use at the LHC have also been studied. With an initial fluence of approximately 3 × 1012 1 MeV neq, a decrease in the Effective Depletion Voltage (EDV) of around 25 V is observed. Following this initial decrease, the EDV increases at a comparable rate to the type inverted n+-on-n type sensors, with rates of (1.43±0.16) × 10−12 V/ 1 MeV neq and (1.35±0.25) × 10−12 V/ 1 MeV neq measured for n+-on-p and n+-on-n type sensors, respectively. A reduction in the charge collection efficiency due to an unexpected effect involving the second metal layer readout lines is observed

Statistical Theory of Spin Relaxation and Diffusion in Solids

A comprehensive theoretical description is given for the spin relaxation and diffusion in solids. The formulation is made in a general statistical-mechanical way. The method of the nonequilibrium statistical operator (NSO) developed by D. N. Zubarev is employed to analyze a relaxation dynamics of a spin subsystem. Perturbation of this subsystem in solids may produce a nonequilibrium state which is then relaxed to an equilibrium state due to the interaction between the particles or with a thermal bath (lattice). The generalized kinetic equations were derived previously for a system weakly coupled to a thermal bath to elucidate the nature of transport and relaxation processes. In this paper, these results are used to describe the relaxation and diffusion of nuclear spins in solids. The aim is to formulate a successive and coherent microscopic description of the nuclear magnetic relaxation and diffusion in solids. The nuclear spin-lattice relaxation is considered and the Gorter relation is derived. As an example, a theory of spin diffusion of the nuclear magnetic moment in dilute alloys (like Cu-Mn) is developed. It is shown that due to the dipolar interaction between host nuclear spins and impurity spins, a nonuniform distribution in the host nuclear spin system will occur and consequently the macroscopic relaxation time will be strongly determined by the spin diffusion. The explicit expressions for the relaxation time in certain physically relevant cases are given.Comment: 41 pages, 119 Refs. Corrected typos, added reference

An Integrated TCGA Pan-Cancer Clinical Data Resource to Drive High-Quality Survival Outcome Analytics

For a decade, The Cancer Genome Atlas (TCGA) program collected clinicopathologic annotation data along with multi-platform molecular profiles of more than 11,000 human tumors across 33 different cancer types. TCGA clinical data contain key features representing the democratized nature of the data collection process. To ensure proper use of this large clinical dataset associated with genomic features, we developed a standardized dataset named the TCGA Pan-Cancer Clinical Data Resource (TCGA-CDR), which includes four major clinical outcome endpoints. In addition to detailing major challenges and statistical limitations encountered during the effort of integrating the acquired clinical data, we present a summary that includes endpoint usage recommendations for each cancer type. These TCGA-CDR findings appear to be consistent with cancer genomics studies independent of the TCGA effort and provide opportunities for investigating cancer biology using clinical correlates at an unprecedented scale. Analysis of clinicopathologic annotations for over 11,000 cancer patients in the TCGA program leads to the generation of TCGA Clinical Data Resource, which provides recommendations of clinical outcome endpoint usage for 33 cancer types

Biased competition through variations in amplitude of γ-oscillations

Experiments in visual cortex have shown that the firing rate of a neuron in response to the simultaneous presentation of a preferred and non-preferred stimulus within the receptive field is intermediate between that for the two stimuli alone (stimulus competition). Attention directed to one of the stimuli drives the response towards the response induced by the attended stimulus alone (selective attention). This study shows that a simple feedforward model with fixed synaptic conductance values can reproduce these two phenomena using synchronization in the gamma-frequency range to increase the effective synaptic gain for the responses to the attended stimulus. The performance of the model is robust to changes in the parameter values. The model predicts that the phase locking between presynaptic input and output spikes increases with attention