Extracting and Stabilizing the Unstable State of Hysteresis Loop

A novel perturbation method for the stabilization of unstable intermediate states of hysteresis loop (i.e. S-shaped curve) is proposed. This method only needs output signals of the system to construct the perturbation form without delay-coordinate embedding technique, it is more practical for real-world systems. Stabilizing and tracking the unstable intermediate branch are demonstrated through the examples of a bistable laser system and delay feedback system. All the numerical results are obtained by simulating each of the real experimential conditions.Comment: 6 pages, REVTEX, 4 ps figure

Binding energies and electronic structures of adsorbed titanium chains on carbon nanotubes

We have studied the binding energies and electronic structures of metal (Ti, Al, Au) chains adsorbed on single-wall carbon nanotubes (SWNT) using first principles methods. Our calculations have shown that titanium is much more favored energetically over gold and aluminum to form a continuous chain on a variety of SWNTs. The interaction between titanium and carbon nanotube significantly modifies the electronic structures around Fermi energy for both zigzag and armchair tubes. The delocalized 3d electrons from the titanium chain generate additional states in the band gap regions of the semiconducting tubes, transforming them into metals.Comment: 4 pages, 3 figure

MicroRNA-17-92 significantly enhances radioresistance in human mantle cell lymphoma cells

The microRNA-17-92 (miRNA-17-92) cluster, at chromosome 13q31-q32, also known as oncomir-1, consists of seven miRNAs that are transcribed as a polycistronic unit. Over-expression of miRNA-17-92 has been observed in lymphomas and other solid tumors. Whether miRNA-17-92 expression affects the response of tumor cells to radiotherapy is not addressed so far. In the present study, we studied the effects of miRNA-17-92 on the radiosensitivity of human mantle cell lymphoma (MCL) cells Z138c. Over-expression of miRNA-17-92 significantly increased survival cell number, cell proliferation and decreased cell death of human MCL cells after different doses of radiation. Immunoblot analysis showed that phosphatase and tension homolog (PTEN) and PHLPP2 was down-modulated and pAkt activity was enhanced in MCL cells after over-expressing miRNA-17-92 after irradiation. These findings are the first direct evidence that over-expression of miRNA-17-92 cluster significantly increases the radioresistance of human MCL cells, which offers a novel target molecule for improving the radiotherapy of MCL in clinic

Performance stability and degradation mechanism of La0.6Sr0.4Co0.2Fe0.8O3-δ cathodes under solid oxide fuel cells operation conditions

The performance stability and degradation mechanism of La0.6Sr0.4Co0.2Fe0.8O3d (LSCF)cathodes and LSCF impregnated Gd0.1Ce0.9O2d (LSCF-GDC) cathodes are investigated undersolid oxide fuel cell operation conditions. LSCF and LSCF-GDC cathodes show initiallyperformance improvement but degrade under cathodic polarization treatment at 750 C for120 h. The results confirm the grain growth and agglomeration of LSCF and in particularGDC-LSCF cathodes as well as the formation of SrCoOx particles on the surface of LSCFunder cathodic polarization conditions. The direct observation of SrCoOx formation hasbeen made possible on the surface of dense LSCF electrode plate on GDC electrolyte. Theformation of SrCoOx is most likely due to the interaction between the segregated Sr and Cofrom LSCF lattice under polarization conditions. The formation of SrCoOx would contributeto the deterioration of the electrocatalytic activity of the LSCF-based electrodes for the O2reduction in addition to the agglomeration and microstructure coarsenin

Imidacloprid adsorption by soils treated with humic substances under different pH and temperature conditions

The mobility of a pesticide in soil is determined by the extent and strength of sorption, which is influenced by either the existing soil humus or exogenous humic substances. Exogenous humic acids (HAs) were added to soil to enhance the amount of soil organic carbon (SOC) by 2.5, 5.0 and 10.0 g kg-1. Imidacloprid sorption of the treated soils was studied at three pH levels (4.5, 6.0 and 7.5) and two temperatures (15 and 25°C). Soil imidacloprid adsorption was related to pH and the type and quantity ofadded HAs. Humic acid (HA) and fulvic acid (FA) derived from peat had different effects on adsorption of imidacloprid. When soil solution pH was 6, the amount of adsorbed imidacloprid was enhanced with increasing exogenous HA. On the contrary, the amount of adsorbed imidacloprid decreased with increasing quantity of exogenous FA. Adsorption of imidacloprid in the FA treatment at 5.0 and 10.0 g kg-1 was lower than the controls (untreated soil or treatment with HAs at 0 g kg-1) when the soil solution pH was 6.0. However adsorption of imidacloprid in the HA treatment was higher than the controls. Imidacloprid adsorption was usually higher under lower pH and/or lower temperature at samecondition. Imidacloprid sorption fitted the Freundlich isotherm, indicating that exogenous humic substances influenced adsorption of imidacloprid, which in turn was affected by environmental conditions such as pH and temperature. Thus, exogenous HA can be used to control the mobility of soil pesticide under appropriate conditions to decrease pesticide pollution diffusion and probably increase effectiveness of pesticides

Computational Analysis of Drought Stress-Associated miRNAs and miRNA Co-Regulation Network in Physcomitrella patens.

miRNAs are non-coding small RNAs that involve diverse biological processes. Until now, little is known about their roles in plant drought resistance. Physcomitrella patens is highly tolerant to drought; however, it is not clear about the basic biology of the traits that contribute P. patens this important character. In this work, we discovered 16 drought stress-associated miRNA (DsAmR) families in P. patens through computational analysis. Due to the possible discrepancy of expression periods and tissue distributions between potential DsAmRs and their targeting genes, and the existence of false positive results in computational identification, the prediction results should be examined with further experimental validation. We also constructed an miRNA co-regulation network, and identified two network hubs, miR902a-5p and miR414, which may play important roles in regulating drought-resistance traits. We distributed our results through an online database named ppt-miRBase, which can be accessed at http://bioinfor.cnu.edu.cn/ppt_miRBase/index.php. Our methods in finding DsAmR and miRNA co-regulation network showed a new direction for identifying miRNA functions

Molecular anchors in the solid state: Restriction of intramolecular rotation boosts emission efficiency of luminogen aggregates to unity

Introduction of freely rotatable tetraphenylethene (TPE) to conventional luminophors quenches their light emissions in the solutions but endows the resultant molecules (TPEArs) with aggregation-induced emission characteristics in the condensed phase due to the restriction of intramolecular rotation. High fluorescence quantum yields up to 100% have been achieved in the films of TPEArs

Quantum Entanglement of Excitons in Coupled Quantum Dots

Optically-controlled exciton dynamics in coupled quantum dots is studied. We show that the maximally entangled Bell states and Greenberger-Horne-Zeilinger (GHZ) states can be robustly generated by manipulating the system parameters to be at the avoided crossings in the eigenenergy spectrum. The analysis of population transfer is systematically carried out using a dressed-state picture. In addition to the quantum dot configuration that have been discussed by Quiroga and Johnson [Phys. Rev. Lett. \QTR{bf}{83}, 2270 (1999)], we show that the GHZ states also may be produced in a ray of three quantum dots with a shorter generation time.Comment: 16 pages, 7 figures, to appear in Phys. Rev.

JCM-16021, a Chinese Herbal Formula, Attenuated Visceral Hyperalgesia in TNBS-Induced Postinflammatory Irritable Bowel Syndrome through Reducing Colonic EC Cell Hyperplasia and Serotonin Availability in Rats

The present study aimed to investigate the analgesic effect of JCM-16021, a revised traditional Chinese herbal formula, on postinflammatory irritable bowel syndrome (PI-IBS) in rats. The trinitrobenzene sulfonic (TNBS) acid-induced PI-IBS model rats were orally administrated with different doses of JCM-16021 (1.2, 2.4, and 4.8 g/kg/d) for 14 consecutive days. The results showed that JCM-16021 treatment dose-dependently attenuated visceral hyperalgesia in PI-IBS rats. Further, the colonic enterochromaffin (EC) cell number, serotonin (5-HT) content, tryptophan hydroxylase expression, and mechanical-stimuli-induced 5-HT release were significantly ameliorated. Moreover, the decreased levels of mucosal cytokines in PI-IBS, especially the helper T-cell type 1- (Th1-) related cytokine TNF-α, were also elevated after JCM-16021 treatment. These data demonstrate that the analgesic effect of JCM-16021 on TNBS-induced PI-IBS rats may be medicated via reducing colonic EC cell hyperplasia and 5-HT availability