Fast Synthesis Algorithm for Uniformly Spaced Circular Array with Low Sidelobe Pattern

© 2018 ACES. In this paper, a highly efficient approach is proposed to synthesize the low sidelobe pattern of uniformly spaced circular array. The proposed approach can be generalized to deal with the pattern synthesis for the circular array with directional elements. Numerical examples are given to verify the effectiveness and advantage of this approach

Real-time counting of single electron tunneling through a T-shaped double quantum dot system

Real-time detection of single electron tunneling through a T-shaped double quantum dot is simulated, based on a Monte Carlo scheme. The double dot is embedded in a dissipative environment and the presence of electrons on the double dot is detected with a nearby quantum point contact. We demonstrate directly the bunching behavior in electron transport, which leads eventually to a super-Poissonian noise. Particularly, in the context of full counting statistics, we investigate the essential difference between the dephasing mechanisms induced by the quantum point contact detection and the coupling to the external phonon bath. A number of intriguing noise features associated with various transport mechanisms are revealed.Comment: 8 pages, 5 figure

Precuneus contributes to attentive control of finger movement

AIM: To examine whether precuneus subserves the attentive control of finger movement or whether it mediates the movement preparation and motor inhibition. METHODS: In the Preparation Stage, subjects were shown with a 5-number string in which each number stood for a key-pressing response, the number strings included a complex pattern (eg, 4-1-4-2-3), or a simple one (eg, 2-2-2-2-2), or a null one (ie, x-x-x-x-x). In the Execution Stage, five reaction signs were presented one by one and subjects were required to press the corresponding key to each sign sequentially (eg, in the 4-1-4-2-3 preparation example, subjects press key 4 to the first sign, press key 1 to the second sign, key 4 to the third sign and so on). For the null preparation pattern, five numbers, rather than the reaction signs, were shown at the same pace as in the other two conditions and subjects were to press the corresponding keys. RESULTS: Left medial frontal gyrus (BA 6) and precentral gyrus (BA 6) were involved in both of the Preparation Stage and the Execution Stage, whereas left precuneus (BA 7) was activated only in the Execution Stage. CONCLUSION: Precuneus mediates the attentive control of finger movement, but not the movement preparation or motor inhibition.AIM: To examine whether precuneus subserves the attentive control of finger movement or whether it mediates the movement preparation and motor inhibition. METHODS: In the Preparation Stage, subjects were shown with a 5-number string in which each number stood for a key-pressing response, the number strings included a complex pattern (eg, 4-1-4-2-3), or a simple one (eg, 2-2-2-2-2), or a null one (ie, x-x-x-x-x). In the Execution. Stage, five reaction signs were presented one by one and subjects were required to press the corresponding key to each sign sequentially (eg, in the 4-1-4-2-3 preparation example, subjects press key 4 to the first sign, press key 1 to the second sign, key 4 to the third sign and so on). For the null preparation pattern, five numbers, rather than the reaction signs, were shown at the same pace as in the other two conditions and subjects were to press the corresponding keys. RESULTS: Left medial frontal gyrus (BA 6) and precentral gyrus (BA 6) were involved in both of the Preparation Stage and the Execution Stage, whereas left precuneus (BA 7) was activated only in the Execution Stage. CONCLUSION: Precuneus mediates the attentive control of finger movement, but not the movement preparation or motor inhibition

How Does Experience Modulate Auditory Spatial Processing in Individuals with Blindness?

published_or_final_versio

Quantum fluctuations in high field magnetization of 2D square lattice J1-J2 antiferromagnets

The J1-J2 square lattice Heisenberg model with spin S=1/2 has three phases with long-range magnetic order and two unconventionally ordered phases depending on the ratio of exchange constants. It describes a number of recently found layered vanadium oxide compounds. A simple means of investigating the ground state is the study of the magnetization curve and high-field susceptibility. We discuss these quantities by using the spin-wave theory and the exact diagonalization in the whole J1-J2 plane. We compare both results and find good overall agreement in the sectors of the phase diagram with magnetic order. Close to the disordered regions the magnetization curve shows strong deviations from the classical linear behaviour caused by large quantum fluctuations and spin-wave approximation breaks down. On the FM side (J1<0) where one approaches the quantum gapless spin nematic ground state this region is surprisingly large. We find that inclusion of second order spin-wave corrections does not lead to fundamental improvement. Quantum corrections to the tilting angle of the ordered moments are also calculated. They may have both signs, contrary to the always negative first order quantum corrections to the magnetization. Finally we investigate the effect of the interlayer coupling and find that the quasi-2D picture remains valid up to |J_\perp/J1| ~ 0.3.Comment: 13 pages, 6figure

SENP3-mediated deSUMOylation of dynamin-related protein 1 promotes cell death following ischaemia

Global increases in small ubiquitin‐like modifier (SUMO)‐2/3 conjugation are a neuroprotective response to severe stress but the mechanisms and specific target proteins that determine cell survival have not been identified. Here, we demonstrate that the SUMO‐2/3‐specific protease SENP3 is degraded during oxygen/glucose deprivation (OGD), an in vitro model of ischaemia, via a pathway involving the unfolded protein response (UPR) kinase PERK and the lysosomal enzyme cathepsin B. A key target for SENP3‐mediated deSUMOylation is the GTPase Drp1, which plays a major role in regulating mitochondrial fission. We show that depletion of SENP3 prolongs Drp1 SUMOylation, which suppresses Drp1‐mediated cytochrome c release and caspase‐mediated cell death. SENP3 levels recover following reoxygenation after OGD allowing deSUMOylation of Drp1, which facilitates Drp1 localization at mitochondria and promotes fragmentation and cytochrome c release. RNAi knockdown of SENP3 protects cells from reoxygenation‐induced cell death via a mechanism that requires Drp1 SUMOylation. Thus, we identify a novel adaptive pathway to extreme cell stress in which dynamic changes in SENP3 stability and regulation of Drp1 SUMOylation are crucial determinants of cell fate

Membrane potential based characterization by flow cytometry of physiological states in an aerobic anoxygenic phototrophic bacterium

A simplified protocol for determination of bacterial membrane potential (MP) by flow cytometry with 3,3'-dihexyloxacarbocyanine iodide (DiOC(6)(3)) as the MP probe was established, and was applied to an aerobic anoxygenic phototrophic bacterium (AAPB strain, Roseobacter clade) with an Escherichia coli strain as a reference. It was shown to be capable of precise indication of the physiological states of the cells as well as cellular responses to environmental factors. Based on the experimental results, a MP curve model was proposed for characterization of species-specific features, which offers parameters including the maximum MP of the curve (MPmax), the time to reach the MPmax (T-max), the slope of the exponential phase of the MP curve (K-MP), and the minimum (threshold) concentration of a particular substrate required for the organism to reach its MPmax (S-max). These parameters are functions of substrates and incubation conditions for a single species, and can be used for comparison between different species under the same conditions. The MPmax, T-max, and K-MP of the AAPB strain were quite different form those of the E. coli strain, and the AAPB strain was shown to be less sensitive to temperature and pH changes than the E. coli strain

The novel mTOR inhibitor RAD001 (Everolimus) induces antiproliferative effects in human pancreatic neuroendocrine tumor cells

Background/Aim: Tumors exhibiting constitutively activated PI(3) K/Akt/mTOR signaling are hypersensitive to mTOR inhibitors such as RAD001 (everolimus) which is presently being investigated in clinical phase II trials in various tumor entities, including neuroendocrine tumors (NETs). However, no preclinical data about the effects of RAD001 on NET cells have been published. In this study, we aimed to evaluate the effects of RAD001 on BON cells, a human pancreatic NET cell line that exhibits constitutively activated PI(3) K/Akt/mTOR signaling. Methods: BON cells were treated with different concentrations of RAD001 to analyze its effect on cell growth using proliferation assays. Apoptosis was examined by Western blot analysis of caspase-3/PARP cleavage and by FACS analysis of DNA fragmentation. Results: RAD001 potently inhibited BON cell growth in a dose-dependent manner which was dependent on the serum concentration in the medium. RAD001-induced growth inhibition involved G0/G1-phase arrest as well as induction of apoptosis. Conclusion: In summary, our data demonstrate antiproliferative and apoptotic effects of RAD001 in NET cells in vitro supporting its clinical use in current phase II trials in NET patients. Copyright (c) 2007 S. Karger AG, Basel

Design of an electrochemical micromachining machine

Electrochemical micromachining (μECM) is a non-conventional machining process based on the phenomenon of electrolysis. μECM became an attractive area of research due to the fact that this process does not create any defective layer after machining and that there is a growing demand for better surface integrity on different micro applications including microfluidics systems, stress-free drilled holes in automotive and aerospace manufacturing with complex shapes, etc. This work presents the design of a next generation μECM machine for the automotive, aerospace, medical and metrology sectors. It has three axes of motion (X, Y, Z) and a spindle allowing the tool-electrode to rotate during machining. The linear slides for each axis use air bearings with linear DC brushless motors and 2-nm resolution encoders for ultra precise motion. The control system is based on the Power PMAC motion controller from Delta Tau. The electrolyte tank is located at the rear of the machine and allows the electrolyte to be changed quickly. This machine features two process control algorithms: fuzzy logic control and adaptive feed rate. A self-developed pulse generator has been mounted and interfaced with the machine and a wire ECM grinding device has been added. The pulse generator has the possibility to reverse the pulse polarity for on-line tool fabrication.The research reported in this paper is supported by the European Commission within the project “Minimizing Defects in Micro-Manufacturing Applications (MIDEMMA)” (FP7-2011-NMPICT- FoF-285614)

Direct Gating of the TRPM2 Channel by cADPR via Specific Interactions with the ADPR Binding Pocket

cADPR is a well-recognized signaling molecule by modulating the RyRs, but considerable debate exists regarding whether cADPR can bind to and gate the TRPM2 channel, which mediates oxidative stress signaling in diverse physiological and pathological processes. Here, we show that purified cADPR evoked TRPM2 channel currents in both whole-cell and cell-free single-channel recordings and specific binding of cADPR to the purified NUDT9-H domain of TRPM2 by surface plasmon resonance. Furthermore, by combining computational modeling with electrophysiological recordings, we show that the TRPM2 channels carrying point mutations at H1346, T1347, L1379, S1391, E1409, and L1484 possess distinct sensitivity profiles for ADPR and cADPR. These results clearly indicate cADPR is a bona fide activator at the TRPM2 channel and clearly delineate the structural basis for cADPR binding, which not only lead to a better understanding in the gating mechanism of TRPM2 channel but also shed light on a cADPR-induced RyRs-independent Ca2+ signaling mechanism