Anti-phase synchronization of phase-reduced oscillators using open-loop control

In this letter, we present an elegant method to build and maintain an anti-phase configuration of two nonlinear oscillators with different natural frequencies and dynamics described by the sinusoidal phase-reduced model. The anti-phase synchronization is achieved using a common input that couples the oscillators and consists of a sequence of square pulses of appropriate amplitude and duration. This example provides a proof of principle that open-loop control can be used to create desired synchronization patterns for nonlinear oscillators, when feedback is expensive or impossible to obtain

Agricultural Academy

Abstract ZECEVIC, V., J. BOSKOVIC, M. DIMITRIJEVIC and S. PETROVIC, 2010. Genetic and phenotypic variability of yield components in wheat (Triticum aestivum L.). Bulg. J. Agric. Sci., Variability, heritability and components of variance for number of grains per spike and grain weight per spike have been studied in 10 winter wheat varieties from different selection centers (Arsenal, KG-56, Gruza, Mironovskaya 808, Norin 10, Rana Niska, Spartanka, Sterna, Osjecanka, and Szegedi 765). The experiment was performed in randomized block design in three replications on the experimental field of Small Grains Research Centre, Kragujevac in three years. Average estimated values for number of grains per spike and grain weight per spike differed significantly among years and among varieties. The highest average value for number of grains per spike had Szegedi 765 variety ( x = 75.1) and the lowest value was found in Spartanka ( x = 56.0). During investigated period the highest average value for grain weight per spike was determined in Gruza ( x = 2.9 g), and the lowest value in Norin 10 ( x = 2.0 g). The average variation coefficient for number of grains per spike was 17.4%, and for grain weight per spike was 21.4%. The lowest variability for number of grains per spike and grain weight per spike was established in Sterna variety (V = 13.0%; 16.2%, respectively) and the highest in Norin 10 variety (V = 21.6%; 25.1%, respectively). Obtained heritability value in broad sense for number of grains per spike was about 60%, and for grain weight per spike about 40%. Statistical analysis of variance established highly significant differences in mean values for number of grains per spike and grain weight per spike. Phenotypic analysis of variance indicated that ecological factors had higher impact on the expression of number of grains per spike and grain weight per spike than genetic factors

Potential Immune Biomarkers in Diagnosis and Clinical Management for Systemic Lupus Erythematosus

Background: There is still no reliable, specific biomarker for precision diagnosis and clinical monitoring of systemic lupus erythematosus. The aim of this study was to investigate the importance of the determination of immunofenotypic profiles (T, B lymphocytes and NK cells) and serum cytokine concentrations (IL-17 and IFN-alpha) as potential biomarkers for this disease. Methods: The study included 55 patients with SLE and 25 healthy controls. The proportion of T, B, NK cells were assessed in peripheral blood using flow cytometric assays while the serum cytokine concentration (IL-17 and IFNalpha) was determined by ELISA test. Results: ROC curve analysis showed good accuracy to distinguish between patients and healthy individuals for activated T cells (AUC=0.798; p<0.001), Treg (AUC= 0.651; p=0.036), and memory B cells (AUC=0.285; p=0.002). We found statistically significant difference (p=0.036) in the levels of serum IL-17 between patients with SLE (IL-17=49.27 pg/mL) and controls (IL-17= 28.64 pg/mL). Conclusions: Significant increase in the relative number of Treg lymphocytes, and decrease in memory B cells, as well as decrease level of IL-17, in SLE patients may be implicated in the pathogenesis of the disease. These parameters, as biomarkers, could distinguish SLE patients and no-SLE patients. Monitoring subpopulations of immune cells in peripheral blood using flow cytometry provides insight into abnormal T and B cell function in SLE. Progress in understanding the immunity at SLE, results in concrete benefits for the SLE patients, which include new clinical management and therapeutic strategies

PAK1 phosphorylation of MEK1 regulates fibronectin-stimulated MAPK activation

Activation of the Ras–MAPK signal transduction pathway is necessary for biological responses both to growth factors and ECM. Here, we provide evidence that phosphorylation of S298 of MAPK kinase 1 (MEK1) by p21-activated kinase (PAK) is a site of convergence for integrin and growth factor signaling. We find that adhesion to fibronectin induces PAK1-dependent phosphorylation of MEK1 on S298 and that this phosphorylation is necessary for efficient activation of MEK1 and subsequent MAPK activation. The rapid and efficient activation of MEK and phosphorylation on S298 induced by cell adhesion to fibronectin is influenced by FAK and Src signaling and is paralleled by localization of phospho-S298 MEK1 and phospho-MAPK staining in peripheral membrane–proximal adhesion structures. We propose that FAK/Src-dependent, PAK1-mediated phosphorylation of MEK1 on S298 is central to the organization and localization of active Raf–MEK1–MAPK signaling complexes, and that formation of such complexes contributes to the adhesion dependence of growth factor signaling to MAPK

Generation of subnanometric platinum with high stability during transformation of a 2D zeolite into 3D

[EN] Single metal atoms and metal clusters have attracted much attention thanks to their advantageous capabilities as heterogeneous catalysts. However, the generation of stable single atoms and clusters on a solid support is still challenging. Herein, we report a new strategy for the generation of single Pt atoms and Pt clusters with exceptionally high thermal stability, formed within purely siliceous MCM-22 during the growth of a two-dimensional zeolite into three dimensions. These subnanometric Pt species are stabilized by MCM-22, even after treatment in air up to 540 degrees C. Furthermore, these stable Pt species confined within internal framework cavities show size-selective catalysis for the hydrogenation of alkenes. High-temperature oxidation-reduction treatments result in the growth of encapsulated Pt species to small nanoparticles in the approximate size range of 1 to 2 nm. The stability and catalytic activity of encapsulated Pt species is also reflected in the dehydrogenation of propane to propylene.This work was funded by the Spanish Government (Consolider Ingenio 2010-MULTICAT (CSD2009-00050) and MAT2014-52085-C2-1-P) and by the Generalitat Valenciana (Prometeo). The Severo Ochoa Program (SEV-2012-0267) is gratefully acknowledged. L.L. thanks ITQ for a contract. The authors also thank the Microscopy Service of UPV for the TEM and STEM measurements. The HAADF-HRSTEM works were conducted in the Laboratorio de Microscopias Avanzadas (LMA) at the Instituto de Nanociencia de Aragon (INA)-Universidad de Zaragoza (Spain), a Spanish ICTS National Facility. Some of the research leading to these results has received funding from the European Union Seventh Framework Program under Grant Agreement 312483-ESTEEM2 (Integrated Infrastructure Initiative-I3). 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