3D DDD modelling of dislocation-precipitate interaction in a nickel-based single crystal superalloy under cyclic deformation

Strain-controlled cyclic deformation of a nickel-based single crystal superalloy has been modelled by using three-dimensional (3D) discrete dislocation dynamics (DDD) for both [001] and [111] orientations. The work focused on the interaction between dislocations and precipitates during cyclic plastic deformation at elevated temperature, which has not been well studied yet. A representative volume element (RVE) with cubic γ’-precipitates was chosen to represent the material, with enforced periodical boundary conditions. In particular, cutting of superdislocations into precipitates was simulated by a back-force method. The global cyclic stress-strain responses were captured well by the DDD model when compared to experimental data, particularly the effects of crystallographic orientation. Dislocation evolution showed that considerably high density of dislocations was produced for [111] orientation when compared to [001] orientation. Cutting of dislocations into the precipitates had a significant effect on the plastic deformation, leading to material softening. Contour plots of in-plane shear strain proved the development of heterogeneous strain field, resulting in the formation of shear-band embryos

Induced four fold anisotropy and bias in compensated NiFe/FeMn double layers

A vector spin model is used to show how frustrations within a multisublattice antiferromagnet such as FeMn can lead to four-fold magnetic anisotropies acting on an exchange coupled ferromagnetic film. Possibilities for the existence of exchange bias are examined and shown to exist for the case of weak chemical disorder at the interface in an otherwise perfect structure. A sensitive dependence on interlayer exchange is found for anisotropies acting on the ferromagnet through the exchange coupling, and we show that a wide range of anisotropies can appear even for a perfect crystalline structure with an ideally flat interface.Comment: 7 pages, 7 figure

A 2 rotaxane-based H-1 NMR spectroscopic probe for the simultaneous identification of physiologically important metal ions in solution

We describe a [ 2] rotaxane molecule that exhibits distinct signals in its H-1 NMR spectra upon the complexation of physiologically important Li+, Na+, Mg2+ and Ca2+ ions; thus, the identification of these metal ions in solution is possible from the analysis of a single H-1 NMR spectrum of a single molecular sensor

Overall Survival with Palbociclib and Fulvestrant in Advanced Breast Cancer

BACKGROUND The cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitor palbociclib, in combination with fulvestrant therapy, prolongs progression-free survival among patients with hormone-receptor–positive, human epidermal growth factor receptor 2 (HER2)–negative advanced breast cancer. We report the results of a prespecified analysis of overall survival. METHODS We randomly assigned patients with hormone-receptor–positive, HER2-negative advanced breast cancer who had progression or relapse during previous endocrine therapy to receive palbociclib plus fulvestrant or placebo plus fulvestrant. We analyzed overall survival; the effect of palbociclib according to the prespecified stratification factors of presence or absence of sensitivity to endocrine therapy, presence or absence of visceral metastatic disease, and menopausal status; the efficacy of subsequent therapies after disease progression; and safety. RESULTS Among 521 patients who underwent randomization, the median overall survival was 34.9 months (95% confidence interval [CI], 28.8 to 40.0) in the palbociclib– fulvestrant group and 28.0 months (95% CI, 23.6 to 34.6) in the placebo–fulvestrant group (hazard ratio for death, 0.81; 95% CI, 0.64 to 1.03; P=0.09; absolute difference, 6.9 months). CDK4/6 inhibitor treatment after the completion of the trial regimen occurred in 16% of the patients in the placebo–fulvestrant group. Among 410 patients with sensitivity to previous endocrine therapy, the median overall survival was 39.7 months (95% CI, 34.8 to 45.7) in the palbociclib–fulvestrant group and 29.7 months (95% CI, 23.8 to 37.9) in the placebo–fulvestrant group (hazard ratio, 0.72; 95% CI, 0.55 to 0.94; absolute difference, 10.0 months). The median duration of subsequent therapy was similar in the two groups, and the median time to the receipt of chemotherapy was 17.6 months in the palbociclib– fulvestrant group, as compared with 8.8 months in the placebo–fulvestrant group (hazard ratio, 0.58; 95% CI, 0.47 to 0.73; P<0.001). No new safety signals were observed with 44.8 months of follow-up. CONCLUSIONS Among patients with hormone-receptor–positive, HER2-negative advanced breast cancer who had sensitivity to previous endocrine therapy, treatment with palbociclib–fulvestrant resulted in longer overall survival than treatment with placebo– fulvestrant. The differences in overall survival in the entire trial group were not significant. (Funded by Pfizer; PALOMA-3 ClinicalTrials.gov number, NCT01942135.

Diffusion in supersonic, turbulent, compressible flows

We investigate diffusion in supersonic, turbulent, compressible flows. Supersonic turbulence can be characterized as network of interacting shocks. We consider flows with different rms Mach numbers and where energy necessary to maintain dynamical equilibrium is inserted at different spatial scales. We find that turbulent transport exhibits super-diffusive behavior due to induced bulk motions. In a comoving reference frame, however, diffusion behaves normal and can be described by mixing length theory extended into the supersonic regime.Comment: 11 pages, incl. 5 figures, accepted for publication in Physical Review E (a high-resolution version is available at http://www.aip.de./~ralf/Publications/p21.abstract.html

Exploration of hyperfine interaction between constituent quarks via eta productions

In this work, the different exchange freedom, one gluon, one pion or Goldstone boson, in constituent quark model is investigated, which is responsible to the hyperfine interaction between constituent quarks, via the combined analysis of the eta production processes, $\pi^{-}p\rightarrow\eta n$ and $\gamma p\rightarrow\eta p$. With the Goldstone-boson exchange, as well as the one-gluon or one-pion exchange, both the spectrum and observables, such as, the differential cross section and polarized beam asymmetry, are fitted to the suggested values of Particle Data Group and the experimental data. The first two types of exchange freedoms give acceptable description of the spectrum and observables while the one pion exchange can not describe the observables and spectrum simultaneously, so can be excluded. The experimental data for the two processes considered here strongly support the mixing angles for two lowest S11 sates and D13 states as about -30 and 6 degree respectively.Comment: 7 pages, 4 figures, 4 table

Functional and genetic analysis of regulatory regions of coliphage H-19B: location of shiga-like toxin and lysis genes suggest a role for phage functions in toxin release

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/74784/1/j.1365-2958.1998.00890.x.pd

Observation of the Decays B0->K+pi-pi0 and B0->rho-K+

We report the observation of B^0 decays to the K^+pi^-pi^0 final state using a data sample of 78 fb^-1 collected by the Belle detector at the KEKB e^+e^- collider. With no assumptions about intermediate states in the decay, the branching fraction is measured to be (36.6^{+4.2}_{-4.3}+- 3.0)*10^-6.We also search for B decays to intermediate two-body states with the same K^+pi^-pi^0 final state. Significant B signals are observed in the rho(770)^- K^+ and K^*(892)^+pi^- channels, with branching fractions of (15.1^{+3.4+1.4+2.0}_{-3.3-1.5-2.1})* 10^-6 and (14.8^{+4.6+1.5+2.4}_{-4.4-1.0-0.9})* 10^-6, respectively. The first error is statistical, the second is systematic and the third is due to the largest possible interference. Contributions from other possible two-body states will be discussed. No CP asymmetry is found in the inclusive K^+pi^-pi^0 or rho^-K^+ modes, and we set 90% confidence level bounds on the asymmetry of -0.12<A_{CP}<0.26 and -0.18<A_{CP}<0.64, respectively.Comment: 18 pages, 7 figure