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Highly flexible, foldable, and rollable microsupercapacitors on an ultrathin polyimide substrate with high power density.
The design and functionality of extremely flexible, foldable, and rollable microsupercapacitors (MSCs) with in-plane interdigital electrodes that consist of single-walled carbon nanotube (SWCNT) networks on an ultrathin polyimide substrate are demonstrated through experiments and finite element simulations. The all-solid-state MSCs can be reversibly bent, folded, and rolled purely elastically without degradation of their electrical performance. The simulation results confirm that the deformation in bent, folded, and rolled MSCs is purely elastic. The high power density (1125 W cm-3) and small time constant (1 ms) of the present MSCs are comparable to those of aluminum electrolytic capacitors. The MSCs operate at scan rates of up to 1000 V s-1, are characterized by a volumetric capacitance of 18 F cm-3 and an energy density of 1.6 mWh cm-3, and exhibit superior electrochemical stability with 96% capacity retention even after 100,000 charge/discharge cycles. The developed MSCs demonstrate high potential for integration in flexible and wearable electronic systems
Pour une approche sociolinguistique en didactique du français langue étrangère —l’argot français contemporain en classe
S’inscrivant dans une perspective de croisement entre la sociolinguistique et la didactique du FLE, cet article vise à esquisser des pistes de réflexion sur l’exploitation de l’argot français contemporain en classe. Nous nous proposons d’exposer
les apprenants à la découverte de cette variété de la langue française, pour éveiller chez eux une prise de conscience de la variation stylistique et par la même occasion développer leur compétence sociolinguistique. En concevant des activités à partir
des documents authentiques, nous avons fait le premier pas vers une mise en œuvre d’une approche sociolinguistique dans l’enseignement du français en Chine
Tunable complex-valued multi-tap microwave photonic filter based on single silicon-oninsulator microring resonator
This paper was published in OPTICS EXPRESS and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: http://dx.doi.org/10.1364/OE.19.012402. Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under lawA complex-valued multi-tap tunable microwave photonic filter based on single silicon-on-insulator microring resonator is presented. The degree of tunability of the approach involving two, three and four taps is theoretical and experimentally characterized, respectively. The constraints of exploiting the optical phase transfer function of a microring resonator aiming at implementing complex-valued multi-tap filtering schemes are also reported. The trade-off between the degree of tunability without changing the free spectral range and the number of taps is studied in-depth. Different window based scenarios are evaluated for improving the filter performance in terms of the side-lobe level. (C) 2011 Optical Society of AmericaThe authors wish to acknowledge the technical support given by Prof. Pascual Munoz and David Domenech, as well as the financial support of the European Commission Seventh Framework Programme (FP 7) project GOSPEL; the Generalitat Valenciana through the Microwave Photonics research Excellency award programme GVA PROMETEO 2008/092 and also the Plan Nacional I + D TEC2007-68065-C03-01 and TEC2008-06145.Lloret Soler, JA.; Sancho Durá, J.; Pu, M.; Gasulla Mestre, I.; Yvind, K.; Sales Maicas, S.; Capmany Francoy, J. (2011). Tunable complex-valued multi-tap microwave photonic filter based on single silicon-on-insulator microring resonator. Optics Express. 19(13):12402-12407. https://doi.org/10.1364/OE.19.012402S1240212407191
Asiatic acid exerts neuroprotective effect against hypoxicischemic brain injury in neonatal rats via inhibition of oxidative damage
Purpose: To investigate the effect of asiatic acid on hypoxic ischemia-induced injury in neonatal rats, and the underlying mechanism of action.Methods: Hypoxic-ischemia (HI) neonatal rat model was established via permanent ligation of the carotid artery, followed by hypoxia (exposure to 8 % oxygen and 92 % nitrogen) for 24 h. Immunofluorescence, using fluorescence microscope, was used for the determination of expressions of p-TAK1, NeuN and GFAP. Western blotting was used for assaying protein expression levels, while TUNEL assay was employed for the measurement of apoptosis.Results: Treatment of rats with asiatic acid prior to HI effectively prevented up-regulation of pTAK1 and decreased the count of p-TAK1-containing astrocytes. The proportion of NeuN containing p-TAK1 in HI rat brain cortex was significantly reduced by asiatic acid (p < 0.05). Treatment of rats with asiatic acid suppressed HI- induced up-regulation of pJNK expression. The HI-induced increase in the expression levels of caspase-3, p53 and p-c-Jun in rat brain cortex were reversed by asiatic acid (p < 0.05). The HImediated up-regulation of expressions of p- JNK, caspase-3, p53 and p-c-Jun in rat brain cortex were inhibited significantly by NG25. Asiatic acid treatment also significantly alleviated HI-mediated increase in apoptosis of neurons in rat brain cortex, when compared to model group (p < 0.05).Conclusion: These findings suggest that asiatic acid prevents HI-induced brain injury in neonatal rats via inhibition of neuronal apoptosis. Moreover, it inhibits TAK1 activation, suppresses p-JNK expression and targets pro-apoptotic factors in brain cortex. Therefore, asiatic acid may be a therapeutic agent for the management of HI-induced brain injury
Comprehensive Evaluation of Wild \u3cem\u3eElymus\u3c/em\u3e L. Germplasm in Inner Mongolia
Grassland degradation is increasing in severity and is an important global issue in the 21st century. Increasing research is being conducted on how to solve these problems (Niu and Jiang 2004). Restoration and revegetation of degraded grassland and the establishment of artificial pastures are important in addressing degradation. Successful restoration requires the identification of species and seed sources that are adapted to the ecological conditions of the restoration site. Elymus L. is a large genus that contains about 150 species distributed across a wide range of ecological sites across temperate and subtropical regions of the world (Dewey 1984; Love 1984). There are at least 12 species in China (Guo 1987). Elymus includes many economically important forage grasses as well as species that possess useful genes for disease resistance, stress tolerance and adaptation, which can potentially be transferred to cereal crops through gene introgression. Species within Elymus have the potential for playing an important role in artificial pasture construction, grassland and animal husbandry development and ecological restoration. However, research is lacking on Chinese Elymus species, which can provide critical information for selecting suitable Elymus varieties and extending their use in China
Inhibition of Glucose-6-Phosphate Dehydrogenase Could Enhance 1,4-Benzoquinone-Induced Oxidative Damage in K562 Cells
Benzene is a chemical contaminant widespread in industrial and living environments. The oxidative metabolites of benzene induce toxicity involving oxidative damage. Protecting cells and cell membranes from oxidative damage, glucose-6-phosphate dehydrogenase (G6PD) maintains the reduced state of glutathione (GSH). This study aims to investigate whether the downregulation of G6PD in K562 cell line can influence the oxidative toxicity induced by 1,4-benzoquinone (BQ). G6PD was inhibited in K562 cell line transfected with the specific siRNA of G6PD gene. An empty vector was transfected in the control group. Results revealed that G6PD was significantly upregulated in the control cells and in the cells with inhibited G6PD after they were exposed to BQ. The NADPH/NADP and GSH/GSSG ratio were significantly lower in the cells with inhibited G6PD than in the control cells at the same BQ concentration. The relative reactive oxygen species (ROS) level and DNA oxidative damage were significantly increased in the cell line with inhibited G6PD. The apoptotic rate and G2 phase arrest were also significantly higher in the cells with inhibited G6PD and exposed to BQ than in the control cells. Our results suggested that G6PD inhibition could reduce GSH activity and alleviate oxidative damage. G6PD deficiency is also a possible susceptible risk factor of benzene exposure
Convergence of regional economic cycles in Turkey
Dissimilar economic fluctuations and asymmetric shocks across the regions of a country might create severe policy distortions that, under these circumstances, aggregate policy interventions (such as taxation and interest rates), are likely to be sub-optimal for at least a fraction of the regions. For instance, monetary policy can hardly satisfy the needs of all regions when some of the regions are experiencing a boom while others are in a recession phase. For these reasons, similarity of regional business cycles and their convergence are highly desirable from a policy viewpoint. The aim of this paper is, therefore, to provide empirical evidence and policy implications in that context. In particular, I analyze business cycle correlations across Turkish provinces and the tendency of these cycles to converge over the period of analysis between 1975-2000 and 2004-2008 (for Nomenclature of Territorial Units for Statistics [NUTS]-2 regions). I find that regional business cycle asymmetries have tended to decrease in recent decades. This result, although it seems to provide evidence in favor of rising correlations, shows that the convergence process is rather slow and there still exist asymmetries across the regional business cycles
Synthesis of electroneutralized amphiphilic copolymers with peptide dendrons for intramuscular gene delivery
Intramuscular gene delivery materials are of great importance in plasmid-based gene therapy system, but there is limited information so far on how to design and synthesize them. A previous study showed that the peptide dendron-based triblock copolymer with its components arranged in a reversed biomembrane architecture could significantly increase intramuscular gene delivery and expression. Herein, we wonder whether copolymers with biomembrane-mimicking arrangement may have similar function on intramuscular gene delivery. Meanwhile, it is of great significance to uncover the influence of electric charge and molecular structure on the function of the copolymers. To address the issues, amphiphilic triblock copolymers arranged in hydrophilic-hydrophobic-hydrophilic structure were constructed despite the paradoxical characteristics and difficulties in synthesizing such hydrophilic but electroneutral molecules. The as-prepared two copolymers, dendronG2(l-lysine-OH)-poly propylene glycol2k(PPG2k)-dendronG2(l-lysine-OH) (rL2PL2) and dendronG3(l-lysine-OH)-PPG2k-dendronG3(l-lysine-OH) (rL3PL3), were in similar structure but had different hydrophilic components and surface charges, thus leading to different capabilities in gene delivery and expression in skeletal muscle. rL2PL2 was more efficient than Pluronic L64 and rL3PL3 when mediating luciferase, β-galactosidase, and fluorescent protein expressions. Furthermore, rL2PL2-mediated growth-hormone-releasing hormone expression could significantly induce mouse body weight increase in the first 21 days after injection. In addition, both rL2PL2 and rL3PL3 showed good in vivo biosafety in local and systemic administration. Altogether, rL2PL2-mediated gene expression in skeletal muscle exhibited applicable potential for gene therapy. The study revealed that the molecular structure and electric charge were critical factors governing the function of the copolymers for intramuscular gene delivery. It can be concluded that, combined with the previous study, both structural arrangements either reverse or similar to the biomembrane are effective in designing such copolymers. It also provides an innovative way in designing and synthesizing new electroneutralized triblock copolymers, which could be used safely and efficiently for intramuscular gene delivery
The NASA Cyclone Global Navigation Satellite System SmallSat Constellation
The NASA Cyclone Global Navigation Satellite System (CYGNSS) mission consists of a constellation of eight microsatellites launched on 15 December 2016 into a common circular orbit at ~525 km altitude and 35 deg inclination. Each observatory carries a four channel bistatic radar receiver to measure GPS signals scattered by the Earth surface. Over ocean, near-surface wind speed, air-sea latent and sensible heat flux, and ocean microplastic concentration are derived from the measurements. Over land, near-surface soil moisture and inland water bodies extent are derived. The measurements penetrate through all levels of precipitation and most vegetation due to the 19 cm wavelength of GPS L1 signals. The sampling produced by the constellation makes possible the reliable detection of short time scale weather events such as flood inundation dynamics immediately after a tropical cyclone landfall and rapid soil moisture dry down immediately after major precipitation events. The sun-asynchronous nature of the CYGNSS orbit also supports full sampling of the diurnal cycle of hydrological dynamics within a short period of time. Summaries are presented of engineering and science highlights of the CYGNSS mission, with particular emphasis on those aspects most directly enabled by the use of a constellation of SmallSats
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