First trial of spatial and temporal fractionations of the delivered dose using synchrotron microbeam radiation therapy

The technical feasibility of temporal and spatial fractionations of the radiation dose has been evaluated using synchrotron microbeam radiation therapy for brain tumors in rats. A significant increase in lifespan (216%, p < 0.0001) resulted when three fractions of microbeam irradiation were applied to the tumor through three different ports, orthogonal to each other, at 24 h intervals. However, there were no long‐term survivors, and immunohistological studies revealed that 9 L tumors were not entirely ablated.     

New pseudophase structure for alpha-Pu

We propose a new pseudophase crystal structure, based on an orthorhombic distortion of the diamond structure, for the ground-state alpha phase of plutonium. Electronic-structure calculations in the generalized-gradient approximation give approximately the same total energy for the two structures. Interestingly, our new pseudophase structure is the same as the gamma-Pu structure except with very different b/a and c/a ratios. We show how the contraction relative to the gamma phase, principally in the z direction, leads to an alpha-like structure in the [0,1,1] plane and reproduces the short range bonds of the alpha phase. This is an important link between two complex structures of Pu and opens new possibilities for exploring the very rich phase diagram of Pu through theoretical calculations.     

Measurement of transverse single-spin asymmetries for Dijet production in proton-proton collisions at sqrt[s]=200 GeV

We report the first measurement of the opening angle distribution between pairs of jets produced in high-energy collisions of transversely polarized protons. The measurement probes (Sivers) correlations between the transverse spin orientation of a proton and the transverse momentum directions of its partons. With both beams polarized, the wide pseudorapidity (-1< or = eta < or = +2) coverage for jets permits separation of Sivers functions for the valence and sea regions. The resulting asymmetries are all consistent with zero and considerably smaller than Sivers effects observed in semi-inclusive deep inelastic scattering. We discuss theoretical attempts to reconcile the new results with the sizable transverse spin effects seen in semi-inclusive deep inelastic scattering and forward hadron production in pp collisions.     

Decatungstate-Photocatalyzed Dearomative Hydroacylation of Indoles: Direct Synthesis of 2-Acylindolines

We report herein a convenient and scalable dearomative hydroacylation reaction of indoles. Employing readily available aldehydes as the acyl source and TBADT as an inexpensive direct HAT photocatalyst, a variety of indoles derivatives were converted into synthetically interesting 2-acylindolines in good to excellent yields as well as great diastereoselectivity under mild conditions. An asymmetric version of the reaction was successfully developed and an experimental mechanistic investigation was carried out in order to gain further insights on the assumed reaction pathway.     

Cation-π Interactions between a Noble Metal and a Polyfunctional Aromatic Ligand: Ag+(benzylamine)

The structure of an isolated Ag⁺(benzylamine) complex is investigated by infrared multiple photon dissociation (IRMPD) spectroscopy complemented with quantum chemical calculations of candidate geometries and their vibrational spectra, aiming to ascertain the role of competing cation-N and cation-π interactions potentially offered by the polyfunctional ligand. The IRMPD spectrum has been recorded in the 800–1800 cm⁻¹ fingerprint range using the IR free electron laser beamline coupled with an FT-ICR mass spectrometer at the Centre Laser Infrarouge d'Orsay (CLIO). The resulting IRMPD pattern points toward a chelate coordination (N-Ag⁺-π) involving both the amino nitrogen atom and the aromatic π-system of the phenyl ring. The gas-phase reactivity of Ag⁺(benzylamine) with a neutral molecular ligand (L) possessing either an amino/aza functionality or an aryl group confirms N- and π-binding affinity and suggests an augmented silver coordination in the product adduct ion .     

Protein aggregation containing beta-amyloid,alpha-synuclein and hyperphosphorylated tau in cultured cells of hippocampus,substantia nigra and locus coeruleus after rotenone exposure

Background  

Protein aggregates containing alpha-synuclein, beta-amyloid and hyperphosphorylated tau are commonly found during neurodegenerative processes which is often accompanied by the impairment of mitochondrial complex I respiratory chain and dysfunction of cellular systems of protein degradation. In view of this, we aimed to develop an in vitro model to study protein aggregation associated to neurodegenerative diseases using cultured cells from hippocampus, locus coeruleus and substantia nigra of newborn Lewis rats exposed to 0.5, 1, 10 and 25 nM of rotenone, which is an agricultural pesticide, for 48 hours.     

Identified hadron compositions in p+p and Au+Au collisions at high transverse momenta at √S(NN)=200 GeV

We report transverse momentum (p(T)≤15 GeV/c) spectra of π(±), K(±), p, p[over ˉ], K(S)(0), and ρ(0) at midrapidity in p+p and Au+Au collisions at √S(NN)=200 GeV. Perturbative QCD calculations are consistent with π(±) spectra in p+p collisions but do not reproduce K and p(p[over ˉ]) spectra. The observed decreasing antiparticle-to-particle ratios with increasing p(T) provide experimental evidence for varying quark and gluon jet contributions to high-p(T) hadron yields. The relative hadron abundances in Au+Au at p(T)?8 GeV/c are measured to be similar to the p+p results, despite the expected Casimir effect for parton energy loss.     

Measurement of the bottom quark contribution to nonphotonic electron production in p + p collisions at √s=200 GeV

The contribution of B meson decays to nonphotonic electrons, which are mainly produced by the semileptonic decays of heavy-flavor mesons, in p + p collisions at √s=200 GeV has been measured using azimuthal correlations between nonphotonic electrons and hadrons. The extracted B decay contribution is approximately 50% at a transverse momentum of pT≥5 GeV/c. These measurements constrain the nuclear modification factor for electrons from B and D meson decays. The result indicates that B meson production in heavy ion collisions is also suppressed at high pT.