Magnetic island evolution under the action of electron cyclotron current drive

The magnetic island evolution under the action of an externally current generated by electron cyclotron (ECCD) wave beams is studied using a reduced resistive magnetohydrodynamics (RRMHD) plasma model. We found interesting and somewhat unexpected features of the actual nonlinear 2-D evolution of the magnetic perturbation depending on the injection time of the radio frequency control. In particular in the linear phase of the magnetic island growth we observe that the complete annihilation of the island width is followed by a spatial phase shift of the island, referred as «flip»instability. On the other hand, a current drive deposition in the Rutherford regime can be accompained by the occurrence of a Kelvin-Helmholtz type shear flow instability, responsible for the onset of a plasma turbulent behavio

Magnetic island evolution under the action of electron cyclotron current drive

The magnetic island evolution under the action of an externally current generated by electron cyclotron (ECCD) wave beams is studied using a reduced resistive magnetohydrodynamics (RRMHD) plasma model. We found interesting and somewhat unexpected features of the actual nonlinear 2-D evolution of the magnetic perturbation depending on the injection time of the radio frequency control. In particular in the linear phase of the magnetic island growth we observe that the complete annihilation of the island width is followed by a spatial phase shift of the island, referred as «flip»instability. On the other hand, a current drive deposition in the Rutherford regime can be accompained by the occurrence of a Kelvin-Helmholtz type shear flow instability, responsible for the onset of a plasma turbulent behavior

OCT4 controls mitotic stability and inactivates the RB tumor suppressor pathway to enhance ovarian cancer aggressiveness

OCT4 (Octamer-binding transcription factor 4) is essential for embryonic stem cell self-renewal. Here we show that OCT4 increases the aggressiveness of high-grade serous ovarian cancer (HG-SOC) by inactivating the Retinoblastoma tumor suppressor pathway and enhancing mitotic stability in cancer cells. OCT4 drives the expression of Nuclear Inhibitor of Protein Phosphatase type 1 (NIPP1) and Cyclin F (CCNF) that together inhibit Protein Phosphatase 1 (PP1). This results in pRB hyper-phosphorylation, accelerated cell proliferation and increased in vitro tumorigenicity of ovarian cancer cells. In parallel, OCT4 and NIPP1/CCNF drive the expression of the central Chromosomal Passenger Complex (CPC) components, Borealin, Survivin and the mitotic kinase Aurora B, promoting the clustering of supernumerary centrosomes to increase mitotic stability. Loss of OCT4 or NIPP1/CCNF results in severe mitotic defects, multipolar spindles and supernumerary centrosomes, finally leading to the induction of apoptosis. These phenotypes were recapitulated in different cancer models indicating general relevance for human cancer. Importantly, activation of these parallel pathways leads to dramatically reduced overall survival of HG-SOC patients. Altogether, our data highlights an unprecedented role for OCT4 as central regulator of mitotic fidelity and RB tumor suppressor pathway activity. Disrupting this pathway represents a promising strategy to target an aggressive subpopulation of HG-SOC cells.Oncogene advance online publication, 20 March 2017; doi:10.1038/onc.2017.20

A Simple Blass Matrix Design Strategy for Multibeam Arbitrary Linear Antenna Arrays

Multibeam antenna arrays are currently recognized as one of the enabling technologies for the next-generation communication standards. One of the key components of these systems is the beamforming network (BFN) that implements the array element excitations. This article addresses this issue by presenting a novel strategy to realize an analog feeding network, which allows an arbitrary linear array (LA) to radiate multiple arbitrary beams. In particular, an iterative procedure is conceived to design a Blass matrix using an identical directional coupler for all nodes, resulting in a very simple structure suitable for large-scale production. Two applications with arbitrary directions are illustrated as proofs-of-concept for the developed architecture: a dual-beam configuration with a null involving an aperiodic LA, and a four-beam configuration involving a periodic LA. For this second application, the effectiveness of the proposed solution is further verified by full-wave simulations and experimental measurements carried out on a fabricated prototype

Fine-tuning the electrostatic properties of an alkali-linked organic adlayer on a metal substrate

The performance of modern organic electronic devices is often determined by the electronic level alignment at a metal–organic interface. This property can be controlled by introducing an interfacial electrostatic dipole via the insertion of a stable interlayer between the metallic and the organic phases. Here, we use density functional theory to investigate the electrostatic properties of an assembled structure formed by alkali metals coadsorbed with 7,7,8,8-tetracyanoquinodimethane (TCNQ) molecules on a Ag(100) substrate. We find that the interfacial dipole buildup is regulated by the interplay of adsorption energetics, steric constraints and charge transfer effects, so that choosing chemical substitutions within TCNQ and different alkali metals provides a rich playground to control the systems’ electrostatics and in particular fine-tune its work-function shift

Approaching the socialist factory and its workforce: considerations from fieldwork in (former) Yugoslavia

The socialist factory, as the ‘incubator’ of the new socialist (wo)man, is a productive entry point for the study of socialist modernization and its contradictions. By outlining some theoretical and methodological insights gathered through field-research in factories in former Yugoslavia, we seek to connect the state of labour history in the Balkans to recent breakthroughs made by labour historians of other socialist countries. The first part of this article sketches some of the specificities of the Yugoslav self-managed factory and its heterogeneous workforce. It presents the ambiguous relationship between workers and the factory and demonstrates the variety of life trajectories for workers in Yugoslav state-socialism (from model communists to alienated workers). The second part engages with the available sources for conducting research inside and outside the factory advocating an approach which combines factory and local archives, print media and oral history