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The nonlinear evolution of the single-mode ablative Rayleigh-Taylor instability is studied in three dimensions. As the mode wavelength approaches the cutoff of the linear spectrum (short-wavelength modes), it is found that the three-dimensional (3D) terminal bubble velocity greatly exceeds both the two-dimensional (2D) value and the classical 3D bubble velocity. Unlike in 2D, the 3D short-wavelength bubble velocity does not saturate. The growing 3D bubble acceleration is driven by the unbounded accumulation of vorticity inside the bubble. The vorticity is transferred by mass ablation from the Rayleigh-Taylor spikes to the ablated plasma filling the bubble volume. [ABSTRACT FROM AUTHOR]

The article discusses a study which examined the effects of adolescent social isolation (ASI) on cognitive function in adult Wistar rats. The researchers determined the brain-derived neurotrophic factor levels (BNFL) in the medial prefrontal cortex and nucleus accumbens of adult rats using an enzyme-linked immunosorbent assay. They found that ASI produced an increased BNFL and an impaired latent inhibition among young adult rats.

Abstract  We investigate in detail the effect of energy-transfer up-conversion (ETU) and excited-state absorption (ESA) in diode-end-pumping quasi-three-level Nd:GdVO4 lasers. The energy levels of Nd:GdVO4 crystals and the rate equation involving ETU and ESA effects are presented. The results of simulation show that the ETU effect is important in quasi-three-level lasers and can provide heating approximately two times higher than that induced by the ESA. Moreover, the relationship between the incident pump power and the 912 nm output power was simulated taking into account the ESA; a comparison with experimental data is also presented. As a result, we conclude that the ESA plays an important role in the high-power pumping field; the estimated equivalent cross-section σESA = (1.0 ± 0.5) ∙ 10−20 cm2. [ABSTRACT FROM AUTHOR]

Summary.  Reversible protein phosphorylation plays a crucial role in the regulation of signaling pathways that control various biological responses, such as cell growth, differentiation, invasion, metastasis and apoptosis. Proteomics is a powerful research approach for fully monitoring global molecular responses to the activation of signal transduction pathways. Identification of different phosphoproteins and their phosphorylation sites by functional proteomics provides informational insights into signaling pathways triggered by all kinds of factors. This review summarizes how functional proteomics can be used to answer specific questions related to signal transduction systems of interest. By examining our own example on identifying the novel phosphoproteins in signaling pathways activated by EB virus-encoded latent membrane protein 1 (LMP1), we demonstrated a functional proteomic strategy to elucidate the molecular activity of phosphorylated annexin A2 in LMP1 signaling pathway. Functional profiling of signaling pathways is promising for the identification of novel targets for drug discovery and for the understanding of disease pathogenesis. [ABSTRACT FROM AUTHOR]

Mirrors will be used as first plasma-viewing elements in optical and laser-based diagnostics in ITER. Deterioration of the mirror performance due to e.g. sputtering of the mirror surface by plasma particles or deposition of impurities will hamper the entire performance of the affected diagnostic and thus affect ITER operation. The Specialists Working Group on First Mirrors (FM SWG) in the Topical Group on Diagnostics of the International Tokamak Physics Activity (ITPA) plays an important role in finding solutions for diagnostic first mirrors. Sound progress in research and development of diagnostic mirrors in ITER was achieved since the last overview in 2009. Single crystal (SC) rhodium (Rh) mirrors became available. SC rhodium and molybdenum (Mo) mirrors survived in conditions corresponding to ~200 cleaning cycles with a negligible degradation of reflectivity. These results are important for a mirror cleaning system which is presently under development. The cleaning system is based on sputtering of contaminants by plasma. Repetitive cleaning was tested on several mirror materials. Experiments comprised contamination/cleaning cycles. The reflectivity SC Mo and Rh mirrors has changed insignificantly after 80 cycles. First in situ cleaning using radiofrequency (RF) plasma was conducted in EAST tokamak with a mock-up plate of ITER edge Thomson Scattering (ETS) with five inserted mirrors. Contaminants from the mirrors were removed. Physics of cleaning discharge was studied both experimentally and by modeling. Mirror contamination can also be mitigated by protecting diagnostic ducts. A deposition mitigation (DeMi) duct system was exposed in KSTAR. The real-time measurement of deposition in the diagnostic duct was pioneered during this experiment. Results evidenced the dominating effect of the wall conditioning and baking on contamination inside the duct. A baffled cassette with mirrors was exposed at the main wall of JET for 23,6 plasma hours. No significant degradation of reflectivity was measured on mirrors located in the ducts. Predictive modeling was further advanced. A model for the particle transport, deposition and erosion at the port-plug was used in selecting an optical layout of several ITER diagnostics. These achievements contributed to the focusing of the first mirror research thus accelerating the diagnostic development. Modeling requires more efforts. Remaining crucial issues will be in a focus of the future work of the FM SWG. [ABSTRACT FROM AUTHOR]

In this work, we study the microwave field driven domain wall (DW) motion in an antiferromagnetic nanowire, using the numerical calculations based on a classical Heisenberg spin model with the biaxial magnetic anisotropy. We show that a proper combination of a static magnetic field plus an oscillating field perpendicular to the nanowire axis is sufficient to drive the DW propagation along the nanowire. More importantly, the drift velocity at the resonance frequency is comparable to that induced by temperature gradients, suggesting that microwave field can be a very promising tool to control DW motions in antiferromagnetic nanostructures. The dependences of resonance frequency and drift velocity on the static and oscillating fields, the axial anisotropy, and the damping constant are discussed in details. Furthermore, the optimal orientations of the field are also numerically determined and explained. This work provides useful information for the spin dynamics in antiferromagnetic nanostructures for spintronics applications. [ABSTRACT FROM AUTHOR]

We study 379 central and 159 satellite early-type galaxies with two-dimensional kinematics from the integral-field survey Mapping Nearby Galaxies at APO (MaNGA) to determine how their angular momentum content depends on stellar and halo mass. Using the Yang et al. group catalog, we identify central and satellite galaxies in groups with halo masses in the range . As in previous work, we see a sharp dependence on stellar mass, in the sense that ∼70% of galaxies with stellar mass tend to have very little rotation, while nearly all galaxies at lower mass show some net rotation. The ∼30% of high-mass galaxies that have significant rotation do not stand out in other galaxy properties, except for a higher incidence of ionized gas emission. Our data are consistent with recent simulation results suggesting that major merging and gas accretion have more impact on the rotational support of lower-mass galaxies. When carefully matching the stellar mass distributions, we find no residual differences in angular momentum content between satellite and central galaxies at the 20% level. Similarly, at fixed mass, galaxies have consistent rotation properties across a wide range of halo mass. However, we find that errors in classification of central and satellite galaxies with group finders systematically lower differences between satellite and central galaxies at a level that is comparable to current measurement uncertainties. To improve constraints, the impact of group-finding methods will have to be forward-modeled via mock catalogs. [ABSTRACT FROM AUTHOR]

We investigate the dynamics of linear entropy of an atom in a tripartite cavity-optomechanical system consisting of a two-level atom in a high-finesse optical cavity with a vibrating mirror at one end. The influence of atomic coherence on the time evolution of linear entropy is examined. It is shown that a Greenberger–Horne–Zeilinger like state can be generated. Moreover, it is found that the entanglement between the atom and the subsystem of field and mirror can be controlled by atomic coherence and the parameters of optomechanical coupling coefficient and atom-field coupling strength. [ABSTRACT FROM AUTHOR]

The hysteresis loops as well as the spin distributions of Sm–Co/α-Fe bilayers have been investigated by both three-dimensional (3D) and one-dimensional (1D) micromagnetic calculations, focusing on the effect of the interface exchange coupling under various soft layer thicknesses ts. The exchange coupling coefficient Ahs between the hard and soft layers varies from 1.8 × 10−6 erg/cm to 0.45 × 10−6 erg/cm, while the soft layer thickness increases from 2 nm to 10 nm. As the exchange coupling decreases, the squareness of the loop gradually deteriorates, both pinning and coercive fields rise up monotonically, and the nucleation field goes down. On the other hand, an increment of the soft layer thickness leads to a significant drop of the nucleation field, the deterioration of the hysteresis loop squareness, and an increase of the remanence. The simulated loops based on the 3D and 1D methods are consistent with each other and in good agreement with the measured loops for Sm–Co/α-Fe multilayers. [ABSTRACT FROM AUTHOR]