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Structural controllability is the generalization of traditional controllability for dynamical systems. During the last decade, interesting biological discoveries have been inferred by applied structural controllability analysis to biological networks. However, false positive/negative information (i.e. nodes and edges) widely exists in biological networks that documented in public data sources, which can hinder accurate analysis of structural controllability. In this study, we propose WDNfinder, a comprehensive analysis package that provides structural controllability with consideration of node connection strength in biological networks. When applied to the human cancer signaling network and p53-mediate DNA damage response network, WDNfinder shows high accuracy on essential nodes prediction in these networks. Compared to existing methods, WDNfinder can significantly narrow down the set of minimum driver node set (MDS) under the restriction of domain knowledge. When using p53-mediate DNA damage response network as illustration, we find more meaningful MDSs by WDNfinder. The source code is implemented in python and publicly available together with relevant data on GitHub: . [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the effect of 2,2′-azobis (2-amidinopropane) dihydrochloride (AAPH)-induced oxidation on the functional, structural properties and proteomic information of arachin. The results showed that moderate oxidation improved the water/oil holding capacity of proteins and increased the emulsifying stability, while excessive oxidation increased the carbonyl content, reduced the thiol content, altered the structure and thermal stability, and reduced most of the physicochemical properties. Through LC-QE-MS analysis, it was observed that oxidation leads to various modifications in arachin, including carbamylation, oxidation, and reduction, among others. In addition, 15 differentially expressed proteins were identified. Through gene ontology (GO) analysis, these proteins primarily affected the cellular and metabolic processes in the biological process category. Further Kyoto encyclopedia of genes and genomes (KEGG) analysis revealed that the "proteasome; protein processing in the endoplasmic reticulum (PPER)" pathway was the most significantly enriched signaling pathway during the oxidation process of arachin. In conclusion, this study demonstrated that AAPH-induced oxidation can alter the conformation and proteome of arachin, thereby affecting its corresponding functional properties. The findings of this study can potentially serve as a theoretical basis and foundational reference for the management of peanut processing and storage. [ABSTRACT FROM AUTHOR]

Holding novel physical properties, high flexibility and strong integration ability with Si-based electronic devices, two-dimensional (2D) non-layered materials have received considerable attentions in recent years. To achieve the 2D anisotropic growth, various strategies have been developed. And a variety of applications have been demonstrated. This review provides an overview on the recent progress of this material family. The scope will cover the preparation strategies, including dry methods and wet chemical approaches, as well as the applications in catalysis, energy conversion and storage, optoelectronic devices and topological crystalline insulators. Conclusion and future perspectives are also given. [ABSTRACT FROM AUTHOR]

• The intelligent composite nanoparticles of LNPs-Au were carefully constructed. • The LNPs-Au can act a nano temperature probe in living body using FIR technique. • The LNPs-Au achieved controllable PTT based on accurate temperature detection. • The LNPs-Au with emission in NIR II achieved fluorescence imaging of deep tissue. To address the poor activity and inaccurate in situ temperature measurements of composite photothermal probes, herein we report lanthanide nanoparticles-gold (LNPs-Au) nanoprobes for fluorescence temperature sensing and controlled photothermal therapy (PTT). The conjugation between LNPs and Au is done via electrostatic interactions. LNPs doped with rare earth cations (Yb3+, Ho3+, Er3+, and Ce3+) fluoresce strongly in the NIR-II region and their emission spectrum does not overlap with the absorption spectrum of Au. The intensities of LNPs-Au emission peaks at 1185 and 1560 nm highly depend on temperature, which is utilized in this study for the non-contact temperature measurements in the biologically relevant range. Deep tissue penetration of NIR-II radiation is observed, which is favorable for real-time temperature sensing. In addition, this radiation does not damage the normal tissue. Moreover, LNPs-Au nanoparticles reduce HeLa cell viability below 40 % and adequately inhibited tumor tissue in mice upon 808-nm irradiation. The results of this study will motivate the development of multifunctional photothermal probes for safer, controllable PTT of cancers with simultaneous temperature monitoring. [ABSTRACT FROM AUTHOR]

Gas-expanded liquids have received significant interest as catalytic reaction media. While most GXL studies involve CO 2 as the expansion gas, there is growing interest in non-CO 2 based GXLs, especially when the expansion gas is also a reactant. In this work, we focus on ethylene as an expansion gas, motivated by recent experimental studies on the catalytic epoxidation of ethylene using ethylene-expanded methanol/H 2 O 2 /water mixtures within metal doped silica mesopores. Reported simulation studies on GXLs, even for bulk properties, have been primarily limited to single-component or binary systems. Here we extend the use of simulation to the study of a bulk ternary GXL system - namely, ethylene-expanded mixtures of methanol and water mixtures. We investigate the phase behavior and transport properties in the liquid phase with respect to temperature, pressure and water content. The model force fields are validated by comparing compositions and transport properties to existing experiments. In addition, we study local liquid solvation structure as a function of composition. [ABSTRACT FROM AUTHOR]

The encapsulation of graphene-based Hall sensors on foil is shown to be an effective method for improving the performance in terms of higher sensitivity for magnetic field detection. Two types of encapsulation were investigated: a simple encapsulation of graphene with polymethyl methacrylate (PMMA) as a proof of concept and an encapsulation with mechanically exfoliated hexagonal boron nitride (hBN). The Hall sensor with PMMA encapsulation already shows higher sensitivity compared to the one without encapsulation. However, the Hall sensor with graphene encapsulated between two stacks of hBN shows a current and a voltage normalized sensitivity of up to 2270 V/AT and 0.68 V/VT, respectively, which are the highest reported sensitivity values for Hall sensors on foil so far. [ABSTRACT FROM AUTHOR]

Magnetic anisotropy is the key element in the construction of single-ion magnets, a kind of nanomagnets for high-density information storage. This works describes an unusual large easy-plane magnetic anisotropy (with a zero-field splitting parameter D of +40.2 cm−1), mainly arising from the second-order spin-orbit coupling effect in a trigonal-planar CoII complex [Li(THF)4][Co(NPh2)3], revealed by combined studies of magnetism, high frequency/field electron paramagnetic resonance spectroscopy, and ab initio calculations. Meanwhile, the field-induced slow magnetic relaxation in this complex was mainly attributed to the Raman process. [ABSTRACT FROM AUTHOR]

Two polymorphs of supramolecular isomers, a discrete dimer and a zig-zag chain, having the same chemical composition, [Mn(Hbit)Cl2] (Hbit=1-methyl-2-(1H-1,2,3-triazol-4-yl)-1H-benzo[d]imidazole), were obtained solvothermally in a one-pot synthesis. The isomers differ in a number of ways: orange blocks versus pale-yellow needles, triclinic P1 versus orthorhombic Pbcn, double µ2-Cl versus alternate single and triple µ2-Cl, coordination number 5 versus 6, and antiparallel versus parallel near-neighbor orientation of Hbit. The packing in each case is driven by the supramolecular interactions, H-bonds (N--H…Cl, C--H…Cl) and π…π overlaps, calculated to be in the range 20-36 kcalmol-1. Calculations gave a difference of only 2 kcalmol-1 in favor of the dimer, which confirms with the observation of principally the dimer at short reaction time. ESI-MS spectra of the dissolved crystals reveal the same fragments with similar distributions. The presence of two fragments at m/z 286.96 [MnIV(Hbit)Cl-2H]+ and 323.94 [MnIII (Hbit)Cl2]+ indicates that [Mn(Hbit)Cl2] is the building unit in both cases; thus, the different orientations of the ligands lead to the two polymorphs stabilized by the respective supramolecular interactions. Importantly, the chain form represents the first example with alternate single and triple µ2-Cl bridges. The magnetic interactions are weakly antiferromagnetic in both cases, with J in the range 0.07-0.34 cm-1; however, high-field EPR analysis reveals moderate magneto-anisotropy with D=0.26(1) cm-1, E=0.06(1) cm-1 and D=0.17(1) cm-1, E=0.03(1) cm-1, respectively. [ABSTRACT FROM AUTHOR]

Induction and mobilization of transposable elements (TEs) following DNA damage or other stresses has been reported in prokaryotes and eukaryotes. Recently it was discovered that eukaryotic TEs are frequently associated with long non-coding RNAs (lncRNAs), many of which are also upregulated by stress. Yet, it is unknown whether DNA damage-induced transcriptional activation of TEs and lncRNAs occurs sporadically or is a synchronized, genome-wide response. Here we investigated the transcriptome of Arabidopsis wild-type (WT) and ataxia telangiectasia mutated ( atm ) mutant plants 3 h after induction of DNA damage. In WT, expression of 5.2% of the protein-coding genes is ≥2-fold changed, whereas in atm plants, only 2.6% of these genes are regulated, and the response of genes associated with DNA repair, replication, and cell cycle is largely lost. In contrast, only less than 0.6% of TEs and lncRNAs respond to DNA damage in WT plants, and the regulation of ≥95% of them is ATM-dependent. The ATM-downstream factors BRCA1, DRM1, JMJ30, AGO2, and the ATM-independent AGO4 participate in the regulation of individual TEs and lncRNAs. Remarkably, protein-coding genes located adjacent to DNA damage-responsive TEs and lncRNAs are frequently coexpressed, which is consistent with the hypothesis that TEs and lncRNAs located close to genes commonly function as controlling elements. [ABSTRACT FROM AUTHOR]

Conjugated polymeric materials characterized by chemical cost benefit, environmental friendliness and richness at the molecular design, are considered as promising electrode materials for LIBs. However, their relatively low capacity, poor structural stability, and sluggish ion/electron diffusion kinetics remain the obstacles and deep exploration of their electrochemical mechanisms are also urgently needed. Here, two triazine-based porous polymeric frameworks with tunable conjugated structures are fabricated and their electrochemical behaviors are explored in-depth to further probe the mechanisms of lithium ions inserting onto aromatic rings. Based on the ex-situ experimental analysis and theoretical calculations, the intercalation of lithium ions is a stepwise process for triazine and benzene units, and the polymer with extended conjugation structures could involve 12 lithium ions intercalation with a high capacity of 1497.6 mAh g-1 after 150 cycles at 100 mA g−1. Furthermore, the full cells also elicit the potential of the ToF-2 as a readily processable anode material with the commercially tested LiCoO 2 as cathode. • Two triazine-based porous polymeric frameworks of ToF-1 and ToF-2 are fabricated. • The in-depth probe of their electrochemical behaviors is studied in detail. • The electrochemical properties could be boosted by extending conjugation structures. • ToF-2 shows a high capacity of 1497.6 mAh g−1 after 150 cycles at 100 mA g−1. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) porous carbon-based composite nanosheets loaded with metal oxide nanoclusters are expected to be promising electrocatalysts for high-performance electrochemical sensors. However, for this complicated composite material, strict reaction conditions and complex synthesis steps limit its general application in electrochemical detection. Here we present a facile method to fabricate 2D mesoporous nitrogen-rich carbon nanosheets loaded with CeO 2 nanoclusters (2D-mNC@CeO 2), for fabricating superoxide anions (O 2 •−) electrochemical sensor. The method is based on block copolymers self-assembly and the affinity of polydopamine to metal ions to obtain organic-inorganic hybrid, which can be directly converted into 2D-mNC@CeO 2 through carbonization strategy without structural deterioration. Characterizations demonstrate that the 2D-mNC@CeO 2 owned the 2D N-doped carbon structure with an interlinked hierarchical mesoporous and the uniformly dispersed CeO 2 nanoclusters on the surface. Benefitted from the unique structure, the 2D-mNC@CeO 2 shortens electron transfer distance, enhances mass transfer efficiency, exposes numerous active sites, and obtain a high Ce3+/Ce4+ ratio for improving electrocatalytic performance. The 2D-mNC@CeO 2 /SPCEs sensors for O 2 •− detection has a detection limit of 0.179 μM (S/N = 3) and sensitivity of 401.4 μA cm-2 mM-1. The sensors can be applied to capture electrochemical signals of O 2 •− released from HepG2 cells, demonstrating the application potential of the sensors to monitor O 2 •− in biological fields. [ABSTRACT FROM AUTHOR]

Anode surface temperature after current zero has a great impact on the interruption capacity of a vacuum interrupter. The objective of this paper is to theoretically investigate the relation between breakdown voltages and anode surface temperature after current zero. A heat conduction model was adopted to describe the temperature development of the anode, taking account of phase transition and evaporation. The breakdown voltages in certain metal vapor densities were obtained by the Particle-in-Cell/Monte Carlo collision (PIC-MCC) method. Finally, the Paschen curve for copper vapor was obtained using the PIC–MCC method and verified by the theoretical model. Moreover, the minimum breakdown voltage, 30 V, was obtained at a density of 1.3\times 10^22/\textm^3 with a gap of 10 mm, which corresponded to a surface temperature of 1983 K. In order to ensure a successful interruption, anode surface temperature should not be higher than 1983 K at current zero, and the melting time should be kept as short as possible. [ABSTRACT FROM PUBLISHER]

Human topoisomerase 1B controls the topological state of supercoiled DNA allowing the progression of fundamental cellular processes. The enzyme, which is the unique molecular target of the natural anticancer compound camptothecin, acts by cleaving one DNA strand and forming a transient protein–DNA covalent adduct. In this work the role of the Gly717 residue, located in a α-helix structure bridging the active site and the linker domain, has been investigated mutating it in Phe. The mutation gives rise to drug resistance in vivo as observed through a viability assay of yeast cells. In vitro activity assays show that the mutant is characterized by a fast religation rate, only partially reduced by the presence of the drug. Comparative molecular dynamics simulations of the native and mutant proteins indicate that the mutation of Gly717 affects the motion orientation of the linker domain, changing its interaction with the DNA substrate, likely affecting the strand rotation and religation rate. The mutation also causes a slight rearrangement of the active site and of the drug binding site, providing an additional explanation for the lowered effect of camptothecin toward the mutant. [ABSTRACT FROM AUTHOR]

Inspired by the highly aligned, well-ordered microstructure, and anisotropic mechanical properties of biological soft tissues, artificial electronic skins (e-skins) have been widely reported in recent years. However, challenges remain in achieving green, high mechanical properties, and multifunctionality simultaneously. In this work, we present a smart e-skin system with an anisotropic structure that couples a cellulose scaffold (CS) derived from natural wood with a polyvinyl alcohol (PVA)/MXene nanosheets (PM) network through a facile freeze-thawing process, featuring high toughness and excellent conductivity. With the addition of a biocompatible cryo-protectant, the smart e-skin exhibit ambient stability, anti-freezing properties, and moisturizing capability. The strong cross-linking and bonding between the 3D hierarchical CS and PM polymer network enhancing the mechanical strength of the e-skin in a specific direction, and the tensile strength along the longitudinal direction reached 12.01 MPa. The wood-derived hydrogel e-skin is 75 times and 23 times stronger than the isotropic cellulose hydrogel and pure PVA hydrogel. The soft PM polymer network endows the rigid cellulose skeleton with outstanding flexibility. Importantly, the e-skin with remarkable electromechanical sensing can realize the real-time monitoring of various human motions. In addition, the e-skin can also realize the private information transmission and even object recognition in aquatic environments. This study provides a facile strategy for developing next-generation wearable devices and multifunctional e-skin systems with bionic characteristics. [ABSTRACT FROM AUTHOR]

As there are some shortages with using both standard calibration method and self-calibration method to calibrate a large Field of View (FOV) binocular stereovision sensor, a two-step calibration method of a large FOV binocular stereovision sensor for onsite measurement is proposed. Furthermore, in order to improve the calibration efficiency, a novel method of corner detection based on region of interest (ROI) is also proposed to quickly detect the chessboard corner in the image of a small calibration target. Compared with the other two methods, the proposed method is more suitable for rapid onsite structure–parameter calibration of a large FOV binocular stereovision sensor. The experiments show that the onsite calibration process is efficient, and the average value of 10 measurements for a distance of 1071 mm is 1071.03 mm with a RMS less than 0.1 mm. Moreover, the application results indicate that the measurement accuracy of the stereovision prototype system calibrated by this method is improved by 13.56% compared with the other from standard calibration method. [ABSTRACT FROM AUTHOR]

We demonstrate strain-induced modulation of perpendicular magnetic anisotropy (PMA) in (001)-oriented [Pb(Mg1/3Nb2/3)O3](1_x)-[PbTiO3]x (PMN-PT) substrate/Ta/CoFeB/MgO/Ta structures using ferromagnetic resonance (FMR). An in-plane biaxial strain is produced by applying voltage between the two surfaces of the PMN-PT substrate, and is transferred to the ferromagnetic CoFeB layer, which results in tuning of the PMA of the CoFeB layer. The strain-induced change in PMA is quantitatively extracted from the experimental FMR spectra. It is shown that both first and second-order anisotropy terms are affected by the electric field, and that they have opposite voltage dependencies. A very large value of the voltage-induced perpendicular magnetic anisotropy modulation of ~7000 fJ/V m is obtained through this strain-mediated coupling. Using this FMR technique, the magnetostriction coefficient λ is extracted for the ultrathin 1.1 nm Co20Fe60B20 layer, and is found to be 3.7 x 10-5, which is approximately 4 times larger than the previously reported values for CoFeB films thicker than 5 nm. In addition, the effect of strain on the effective damping constant (aeff) is also studied and no obvious modulation of the aeff is observed. The results are relevant to the development of CoFeB-MgO magnetic tunnel junctions for memory applications. [ABSTRACT FROM AUTHOR]

Network communication traditionally only uses encryption techniques for privacy and a single path for routing, which makes the communication vulnerable to attackers. Attackers easily obtain much important information by eavesdropping on the path and analyzing the communication traffic. To overcome the problem, we propose concurrent multipath traffic impersonating (CMTI), which obscures traffic features by camouflaging the traffic flow and dividing it into multiple parts. We propose a traffic impersonating technique based on statistical simulation, which make the secret traffic look like another normal and inconspicuous class to deceive attackers. And we present the packet scheduling algorithm to transfer the impersonating flows on multipath, for enhancing the communication efficiency and further increasing significantly the cost inflicted on attackers who wish to eavesdrop communication sessions. The empirical analysis demonstrates that concurrent multipath traffic imitating can effectively thwart traffic analysis and enhance communication efficiency. [ABSTRACT FROM AUTHOR]

Membrane surface and cross-sectional morphology created during membrane formation is one of the most essential factors determining membrane separation performance. However, the complicated interactions between added nanoparticles and additives influencing membrane morphology and performance during building membrane architectures had been generally neglected. In this study, asymmetric PVDF composite ultrafiltration (UF) membranes containing graphene oxides (GO) were prepared by using N-methyl pyrrolidone (NMP) as solvent and polyvinylpyrrodione (PVP) as the pore forming reagent. In the first time, the effects of mutual interactions between GO and PVP on membranes surface compositions, morphology and performance were investigated in detail. The variation in chemical properties of different membranes and hydrogen bonds in the membrane containing GO and PVP were confirmed by X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR). Atomic force microscopy (AFM), scanning electron microscopy (SEM), and contact angle (CA) were utilized to clarify the synergetic effects of GO and PVP on morphologies and surface hydrophilicity of membranes. Besides, water flux, bovine serum albumin (BSA) rejection and attenuate coefficient were also determined to investigate filtration performance of various membranes. Compared with pure PVDF membrane, the comprehensive performance of PVDF/GO/PVP membrane has been obviously improved. The surface hydrophilicity and anti-fouling performance were enhanced by the synergistic effects of incorporated GO and PVP. When the PVP content was 0.25 wt.% and the GO content was 0.5 wt.%, the optimized performance can be obtained due to the formation of hydrogen bonds between GO and PVP. [ABSTRACT FROM AUTHOR]

Background and Aim: This study was undertaken to evaluate the clinical characteristics, prognostic factors, and long-term outcomes of patients with mucosa-associated lymphoid tissue (MALT) lymphoma in the gastrointestinal (GI) tract. Methods: Clinical and pathological features of patients with MALT lymphoma in the GI tract, who were treated consecutively at Tianjin Medical University Cancer Institute and Hospital from 2001 to 2011, were evaluated retrospectively. Results: Among a total of 99 identified cases, 79.79% of lymphomas were localized in the stomach, 20.20% in the intestinal tract, and disseminated disease was detected in 35.4% of cases. The estimated 5-year overall survival (OS) and 5-year progression-free survival (PFS) rates were 73.1% and 65.1%, respectively. The comparison between stomach and intestinal tract lymphomas demonstrated no significant difference in characteristics, but nodal involvement was significantly lower in gastric MALT lymphoma (26.6%) as compared with intestinal tract MALT lymphoma (60%, P = 0.006). The outcomes of gastric and intestinal MALT lymphomas were similar (OS, P = 0.492; PFS, P = 0.408), and so was the survival between proximal and distal gastric lymphomas (OS, P = 0.077; PFS, P = 0.181). Serum lactate dehydrogenase level above normal was identified as the only adverse prognostic factor for both OS and PFS. Conclusion: The clinical characteristics and outcomes demonstrated no significant differences between gastric and intestinal tract MALT lymphomas. Serum lactate dehydrogenase level was an independent prognostic factor for the survival of GI MALT lymphoma. [ABSTRACT FROM AUTHOR]

Multilayer ceramic actuators with a base metal internal electrode are in great demand because of their high voltage-driven displacement. Thus, the piezoelectric materials should be sintered in low oxygen partial pressure. The (Li, Ta, Sb)-doped (K,Na)NbO3 (KNN)-based ceramics are heat-treated in O2, air, N2, and 99 vol. % N2/1 vol. % H2 mixture gas at 300 °C in this study to identify the predominant charge carriers by defect chemistry. By analyzing electrical conduction and dielectric relaxation mechanisms, the dominant charge carriers in the ceramics are electrons and oxygen vacancies at low (<450 °C) and high temperature (>500 °C), respectively. In addition, the defect concentration in the ceramics increases with the decreasing oxygen partial pressures, and the change is more evident in the presence of H2 gas. Correspondingly, the electrical properties slightly degrade with the decreasing oxygen partial pressure and severely degrade in the N2/H2 mixture gas. Therefore, the (Li, Ta, Sb)-doped KNN-based ceramics with an n-type conduction mechanism are difficult to sinter in a reducing atmosphere. In order to cofire with base metal electrodes, the p-type conduction should be designed by doping the KNN ceramic in the future for industrial application. [ABSTRACT FROM AUTHOR]

Anode surface temperature has a significant impact on the interruption capacity of a vacuum circuit breaker. The objective of this paper is to experimentally understand the decay process of anode surface temperature after extinguishing a high-vacuum arc with a large contact gap. The anode surface temperature after current zero was measured by a two-color pyrometer and arc modes observation was recorded by a highspeed charge-coupled device. A pair of asymmetric butt type contacts (contact materials: CuCr25 and CuCr50) was subjected to an axial magnetic field in a demountable vacuum chamber. The experimental result shows that there are two modes in decay processes of anode surface temperature: Mode I and Mode II. Mode I describes the anode surface decay process after diffuse low-current extinction and Mode II corresponds to high current extinction. In addition, the decay time of anode surface temperature will last longer, if the proportion of chromium rises from 25% to 50% in anode material. [ABSTRACT FROM PUBLISHER]

Although nowadays Internet is facing more and more threats, very few works have investigated the security situation assessment for inter‐domain routing system which is the most significant infrastructure of Internet. To deal with the problem, a situation assessment model based on the immune Danger Theory is proposed. In this study, the authors first give a comprehensive description of the model architecture as well as practical considerations, and then the main components including signal mapping, antigen selection, routing behaviour analysis and global situation assessment are, respectively, defined and illustrated. Evaluations are launched in view of Japan earthquake and YouTube hijacking, and the results show that the model is able to assess the global anomalous degree of specific inter‐domain routing system quantitatively, which can provide network administrator with accurate and timely information to conduct network monitoring and route protection. [ABSTRACT FROM AUTHOR]

We demonstrate that high-quality vertically aligned SnSe nanorod (NR) arrays have been synthesized via a facile chemical vapor deposition method on SiO2 substrates using Bi powder as catalysts. Both SEM and TEM measurements reveal that this kind of SnSe NR consists of a one-dimensional core and dense two-dimensional branches. Thermistors and photoresistors have been fabricated in situ by directly depositing silver paint on the growth substrates. The thermistor shows the great merits of a broad temperature range (77−390 K), linear input–output characteristic, suitable thermal index and high sensitivity. The photoresistor device exhibits relatively fast response time, linear input–output, high reversibility and stability. In addition, both of the devices have the advantages of low cost, environment-friendliness and easy fabrication. The high performance of SnSe thermistors and photodetectors will make SnSe material promising in industrial multi-function nanodevices. [ABSTRACT FROM AUTHOR]

Permanent magnetic actuators (PMAs) have been widely used in medium-voltage vacuum circuit breakers (VCBs) due to their high reliability and controllability. However, a conventional bistable PMA cannot be adopted in power equipment for the transmission voltage level such as 126 kV VCBs directly because of its low-velocity characteristics. The objective of this paper is to propose a multimagnetic circuit PMA to satisfy the high-velocity requirements for 126 kV VCBs. The novel PMA is a bistable and axisymmetric structure, including holding and driving components whose magnetic circuits are separated. Air gaps are specifically designed in the magnetic circuits to improve the velocity performance of the novel PMA. Both static and dynamic characteristics of the novel PMA model have been calculated through finite-element software coupled with multi-body dynamics software. Furthermore, a prototype of the PMA has been developed according to the calculation results. The experimental results on the prototype have shown that the velocity characteristics of the PMA are able to meet the requirements of a 126 kV VCB and agree well with the simulation results. [ABSTRACT FROM PUBLISHER]

The exotic band structures and distinctive physical properties of two-dimensional materials have exhibited great potential for fundamental research and technical applications in spintronics, electronics, photonics, optoelectronics, and so forth. Facing the challenge of effective synthesis of WSe2 two-dimensional sheets, for the first time we demonstrate a straightforward catalyst-free vapor–solid (VS) growth method to synthesize ultrathin, even monolayer, WSe2 sheets with high yield, regular shapes and high quality optical properties on sapphire substrates. By detailed layer-number-dependent photoluminescence measurements at a low temperature of 40 K, we find the spin–orbit splitting at the K point of the WSe2 valence band with a fixed energy difference of 0.36 eV independent of layer number and the transition of indirect-to-direct gap when the thickness decreases to monolayer. These results, comparable to those of mechanically peeled WSe2 sheets, further prove the high optical and crystal quality of our WSe2 nanosheets via the VS growth approach. Our efforts may open up new exciting opportunities in future valley-based electronics, optoelectronics and photonics. [ABSTRACT FROM AUTHOR]

A novel chemiluminescence resonance energy transfer (CRET) system for competitive immunoassay of biomolecules was developed by using novel amorphous carbon nanoparticles (CNPs) prepared from candle soot as energy acceptors. The CNPs were firstly prepared to bind with the antigen (Ag) for obtaining the nanocomposite CNP–Ag, and this obtained CNP–Ag was then reacted with the horseradish peroxidase-labeled antibody (HRP-Ab) to assemble the CRET system. The luminol catalyzed by HRP serving as the energy donor for CNPs triggered the CRET phenomenon between luminol and CNPs, which led to the chemiluminescence signal decrease. Due to the competitive immunoreaction of the target antigen and the CNP–Ag, a part of the CNP–Ag was replaced from the HRP-Ab, and then resulted in a weaker interaction between luminol and CNPs. Thus the competitive immunoreaction led to a higher chemiluminescence emission. This CNP-based CRET system was successfully applied to detect the human IgG as a model analyte, and a linear range of 10–200 ng mL−1 and a detection limit of 1.9 ng mL−1 (S/N = 3) were obtained. The results for real sample analysis demonstrated its application potential in some important areas such as clinical diagnosis. [ABSTRACT FROM AUTHOR]

Abstract: An onsite structure-parameter calibration method for large field of view (FOV) binocular stereovision based on a small-size 2D target is proposed. Compared with the traditional large-size target, a small-size 2D target is much easier to be manufactured with high accuracy and can be used in onsite calibration. Compared with the 1D target, a 2D target can complete the calibration quickly with fewer calibration images. Additionally, operating and maintaining a small-size 2D target are considerably convenient and flexible. Calibration experiments show that only 5 placements of the calibration target can accomplish the accurate calibration of structure parameters and the average value of 10 measurements for a distance of 1071mm is 1071.057mm with a RMS less than 0.2mm. Moreover, the measurement accuracy of the stereovision calibrated with our method is a little more accurate than that of the one calibrated with traditional method. [Copyright &y& Elsevier]

Highlights: [•] Sex expression in male flowers of Amur grape appears to be sensitive to exogenous, applications of CPPU. [•] Pistil development of male flowers was arrested before 4-nucleate embryo sac. [•] CPPU accelerated pistil development of male flowers, and finally induced octonucleate maturing embryo sac. [•] Difference of berry characteristics in different male Amur grape lines was significant. [ABSTRACT FROM AUTHOR]

[Display omitted] • Porous hydrogel sponge has been realized via in-situ growth of hydrogel on sponge. • Hydrogel layer can be readily controlled to reserve the porosity of the sponge. • The "porous hydrogel sponge" can be arbitrarily compacted, folded, and twisted. • Water evaporation rate is up to 2.8 kg m-2h−1 under one sun with 332 g h−1 $−1. • Long-term cycling stability (>6 months), as large as 7500 cm2. Hydrogel evaporator is becoming an excellent platform for solar-driven water purification. However, the cost effectiveness and scalability of hydrogel-based evaporate materials is still a great challenge due to the high energy-consuming and time-consuming freeze drying process, as well as limited black hydrogel materials. Herein, inspired by porifera, "porous hydrogel sponge" has been proposed and realized via in-situ growth of novel adhesive/black hydrogel on polyurethane (PU) sponge without freeze drying process for durable and highly efficient solar-driven water evaporation. The in-situ generated hydrogel can firmly adhere on the sponge skeleton just like a skin, and the thickness of the hydrogel layer can be readily controlled to reserve the high porosity of the sponge, while the sponge skeleton can endow the evaporator with desirable mechanical stability (can be arbitrarily compacted, folded, and twisted). The water evaporation rate of the resultant hydrogel evaporator can reach up to 2.8 kg m-2h−1 under one sun with excellent cost-effectiveness at 332 g h−1 $−1. Moreover, the resultant hydrogel evaporator possesses outstanding long-term cycling stability (at least 6 months), and can be as large as 7500 cm2 (can be readily enlarged further). This study represents a new avenue for fabrication and design of high performance hydrogel evaporator toward practical application, and will contribute to the global effort in addressing world water and energy issues. [ABSTRACT FROM AUTHOR]

Signal amplification is crucial to improve the sensitivity for the electrochemical detection of cardiac troponin I (cTnI), one of the ideal biomarkers for early acute myocardial infarction (AMI) diagnosis. Herein, we developed a novel signal amplification strategy to construct a sandwich-type electrochemical aptasensor for the detection of cTnI. Core-shell Pd@Pt dendritic bimetallic nanoparticles loaded on melamine modified hollow mesoporous carbon spheres (Pd@Pt DNs/NH 2 -HMCS) was prepared as labels to conjugate with thiol-modification DNA aptamers probe for signal amplification. While introducing numerous amino groups, the melamine functionalized hollow mesoporous carbon spheres (NH 2 -HMCS) retained the edge-plane-like defective sites for the adhesion and electrocatalytic reduction of H 2 O 2. With the unique characteristics of NH 2 -HMCS, it not only enhanced the dispersity and loading capacity of core-shell Pd@Pt dendritic bimetallic nanoparticles (Pd@Pt DNs), but also improved the stability of bonding by the affinity interaction between Pd@Pt DNs and amino groups of melamine. Meanwhile, the synergistic catalysis effect between Pd@Pt DNs and NH 2 -HMCS significantly enhanced the electrocatalytic reduction of H 2 O 2 and further amplified the signal. Under optimal conditions, this recommended aptasensor for cTnI detection displayed a wide dynamic range from 0.1 pg/mL to 100.0 ng/mL and a low detection limit of 15.4 fg/mL (S/N = 3). The sensor also successfully realized the analysis of cTnI-spiked human serum samples, meaning potential applications in AMI diagnosis. [Display omitted] • A facile strategy for preparing melamine-modified carbon materials as superb support matrix was presented. • Based on the strategy, amino groups-enriched NH 2 -HMCS retained its advantages of morphology characteristics. • Pd@Pt DNs/NH 2 -HMCS as a signal amplification label showed excellent electrocatalytic performance for the reduction of H 2 O 2. • A novel sandwich-type electrochemical aptasensor was designed for detecting cTnI. • The sensitive aptasensor possessed a wide dynamic range and low detection limit for detecting cTnI. [ABSTRACT FROM AUTHOR]

A semiconductor/environment interface has been formed in which suspended silicon nanowires (SiNWs) are in direct contact with photoactive TiO2 quantum dots. The photoactivity of TiO2 competes with the intrinsic photoresponses of p‐type silicon nanowires. Rational control of the competitive mechanism realizes remarkable mirror‐imaging photo‐switching and superior rectifying effects in a single SiNW‐based device. [ABSTRACT FROM AUTHOR]

An einer Schnittstelle zwischen Halbleiter und Umgebung sind freihängende Siliciumnanodrähte (SiNWs) in direktem Kontakt mit TiO2 ‐ Quantenpunkten, deren Photoaktivität mit der intrinsischen Photoempfindlichkeit der p ‐ Siliciumnanodrähte überlagert. Durch Ausbalancieren der konkurrierenden Mechanismen können bemerkenswerte Photoschaltungs ‐ und starke Gleichrichtungseffekte in einer einzigen Funktionseinheit auf SiNW ‐ Basis realisiert werden. [ABSTRACT FROM AUTHOR]

Field-effect transistors (FETs) fabricated on large diameter carbon nanotubes (CNTs) present typical ambipolar transfer characteristics owing to the small band-gap of CNTs. Depending on the DC biasing condition, the ambipolar FET can work in three different regions, and then can be used as the core to realize multifunctional AC circuits. The CNT FET based circuits can work as a high-efficiency ambipolar frequency doubler in the ambipolar transfer region, and also can function as in-phase amplifier and inverted amplifier in the linear transfer region. Due to current saturation of the CNT FET, an AC amplifier with a voltage gain of 2 is realized when the device works in the linear transfer region. Achieving an actual amplification and frequency doubling functions indicates that complicated radio frequency circuits or systems can be constructed based on just one kind of device: ambipolar CNT FETs. [ABSTRACT FROM AUTHOR]

Coaxial core/shell nanostructures with type II band alignment have attracted considerable attention due to their advantages in significant enhancement of visible light absorption, effective charge separation, and improved photoelectrochemical performance. In our study, ZnO/ZnSxSe1-x/ZnSe core/shell/shell nanowires have been synthesized via an effective chemical vapor deposition method. The photocurrent is significantly enhanced step-by-step from pristine ZnO, ZnO/ZnSxSe1-x core/shell, to ZnO/ZnSxSe1-x/ZnSe double-shelled nanowire photoelectrodes. The optical properties of this double-shelled nanowires are systematically studied by photoluminescence and time resolved photoluminescence. Our findings not only open an avenue for synthesis sophisticated core/shell nanowires but also pave a way towards improving photoelectrochemical properties in nanostructures. [ABSTRACT FROM AUTHOR]

Graphene is considered as a promising material to construct field-effect transistors (FETs) for high frequency electronic applications due to its unique structure and properties, mainly including extremely high carrier mobility and saturation velocity, the ultimate thinnest body and stability. Through continuously scaling down the gate length and optimizing the structure, the cut-off frequency of graphene FET (GFET) was rapidly increased and up to about 300 GHz, and further improvements are also expected. Because of the lack of an intrinsic band gap, the GFETs present typical ambipolar transfer characteristic without off state, which means GFETs are suitable for analog electronics rather than digital applications. Taking advantage of the ambipolar characteristic, GFET is demonstrated as an excellent building block for ambipolar electronic circuits, and has been used in applications such as highperformance frequency doublers, radio frequency mixers, digital modulators, and phase detectors. [ABSTRACT FROM AUTHOR]

For the first time, high quality In2Te3 nanowires were synthesized via a chemical vapor deposition (CVD) method. The synthesized In2Te3 nanowires are single crystals grown along the [132] direction with a uniform diameter of around 150 nm and an average length of tens of micrometers. Further, two kinds of photodetectors made by 1D In2Te3 nanostructures synthesized by CVD and solvothermal (ST) methods respectively were fabricated. To our best knowledge, this is the first time photoresponse properties of In2Te3 nanowire have been studied. The CVD grown nanowire device shows better performance than the ST device, which demonstrates a fast, reversible, and stable photoresponse and also a broad light detection range from 350 nm to 1090 nm, covering the UV–visible–NIR region. The excellent performance of the In2Te3 nanowire photodetectors will enable significant advancements of the next-generation photodetection and photosensing applications. [ABSTRACT FROM AUTHOR]

SUMMARY There have been many researches on border gateway protocol (BGP) security, most of which mainly focused on how to enhance the security of the BGP protocol or the interdomain routing system. However, few works studied the vulnerabilities especially the production mechanism of security events in the interdomain routing system. It takes many obstacles to understand and improve the security of the interdomain routing system. This paper explores the cascading failure phenomenon of the interdomain routing system. First, we devise a state machine to describe the state transition of BGP nodes and then give a detailed analysis of the BGP failure. Second, on the basis of the preferential attachment characteristic, we propose a cascading failure model for the interdomain routing system, which depicts the production mechanism of cascading failure, and introduce two evaluating indicators, the proportion of failed nodes and the proportion of failed links, to assess the scale of cascading failure. Furthermore, we apply the cascading failure model to display two different cascading failure scenes. The experimental results show that random failure has less influence on the interdomain routing system, while its robustness against hostile attack is weak. Copyright ©2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this article, piezoelectric ceramic is a core device of an ultrasonic wireless power transmission (UWPT) system. The most commonly used piezoelectric ceramic in research and applications of UWPT has a ring-like shape. The piezoelectric ceramic rings usually work in the presence of significant radial and axial vibrations as long as they are not extremely thin. However, in most studies related to the UWPT, only the axial vibration mode is considered. The Mason equivalent circuit model of axial vibration is widely used and the effect of radial vibration on the whole system is ignored. In this article, first, a method to analyze the piezoelectric ceramic ring considering the radial-axial coupled vibration is proposed. Second, the analytical expressions of the constitutive equations of the piezoelectric ceramic ring are derived. Third, a new form of analytical equations is constructed, and a novel two-dimensional equivalent circuit of the UWPT system considering the radial-axial coupled vibration of the piezoelectric ceramic ring is proposed. Fourth, the input and output characteristics of the proposed model and the conventional Mason equivalent circuit model are simulated using MATLAB. Last, the simulation results are compared and verified by experiments. The results demonstrate that the proposed model can describe the system resonance more accurately and comprehensively than the conventional Mason model. As a whole, this study increases the accuracy of the equivalent circuit model of the UWPT system and has important theoretical significance for UWPT research. [ABSTRACT FROM AUTHOR]

The nature of the interfacial structure between the coreand thearms of a tetrapod quantum dot (QD) formed during the heteroepitaxialgrowth of a ZnS arm onto a CdSe core is not well understood but canbe analyzed through the use of high-frequency electron paramagneticresonance (HF-EPR) spectroscopy. The spectroscopic resolution at highfrequency allows the presence of unique crystal fields reflectinginterfacial alloying to be analyzed by incorporating Mn(II) ions asa dopant into the QD to act as an intentional EPR active spectroscopicprobe. In addition, the HF-EPR can spectroscopically observe the presenceof ion vacancies that are anticipated to form at the heteroepitaxialinterface to accommodate structural mismatch. The HF-EPR spectra forMn(II) are extremely sensitive to perturbations of the microenvironmentdue to changes in the crystal field. The HF-EPR spectra of Mn(II)in a CdSe (core)/ZnS (arm) tetrapod exhibiting wurtzite symmetry forboth core and interface of the tetrapod provide clear evidence ofheteroalloying at the core–arm interface and formation of intrinsicdislocations at grain boundaries. The formation of the interfacialalloy and grain boundaries reflects short-range ion migration at theheteroepitaxial layer to reduce strain energy due to the 12% latticemismatch between the wurtzite lattices of CdSe and ZnS. [ABSTRACT FROM AUTHOR]

The Ce-doped BiFeO3 ( BFO) nanoparticles ( NPs) were synthesized using a facile sol-gel route with varying Ce concentrations in the range of 1-5 mol%. Ferroelectric transition temperature was found to shift from 723°C ± 5°C for pristine BFO NPs to 534°C ± 3°C for 5 mol% Ce-doped BFO NPs. UV- Vis absorption spectra of BFO NPs showed a significant blue shift of ~100 nm on Ce doping. The Fourier transformed infrared ( FTIR) spectrum centered ~ 550 cm−1 becomes considerably broadened on Ce doping which is due to additional closely spaced vibrational peaks as revealed by the second derivative FTIR analysis. High-frequency EPR measurements indicated that clustering occurs at high dopant levels, and that Fe is present as Fe3+, corroborating Mössbauer measurements. The values of saturation and remanent magnetization for 3% Ce-doped BFO NPs are 3.03 and 0.49 emu/g, respectively, which are quite significant at room temperature, making it more suitable for technological applications. [ABSTRACT FROM AUTHOR]

Because the slag can be a major source of soil and groundwater pollution, understanding the release and leaching behavior of hexavalent chromium [Cr(VI)], from chromium-containing slag is critical. We report Cr(VI) behavior after static and dynamic leaching from chromium-containing slag deposited at a ferro-alloy manufacturing plant in Hunan province, China. Bench-scale experiments indicate that the main factors influencing the dissolution release of Cr(VI) include the solid-liquid ratio, soak time, agitation, acidity, particle size, and water dynamic flow. Based on the parameters obtained from the dynamic leaching experiment, a Cr(VI) release and leaching model was developed and applied to the study area. The model can quantitatively predict the extent of Cr(VI) pollution of soil and groundwater under atmospheric precipitation. [ABSTRACT FROM AUTHOR]

Abstract: High-frequency electron paramagnetic resonance (HF-EPR) provides a contactless microscopic probe of magnetic impurities and their surroundings in nanoparticles. In 5.0nm colloidally prepared CdSe quantum dots (QDs) containing 0.6% Mn2+, a core and a surface site can be readily distinguished on the basis of g-factor and 55Mn hyperfine interaction. In contrast to EPR in the bulk, at low temperatures a broad background signal develops, which at high fields is the only remaining feature. Previous studies have suggested this background signal originates from exchange coupled Mn2+ clusters arising from spinodal decomposition; HF-EPR shows that it is due to strain-broadening of the zero-field splitting related to local lattice distortions within the QD. [Copyright &y& Elsevier]

Abstract: A simple and sensitive method for amplified chemiluminescent immunoassay has been developed by using multiple signal antibodies functionalized titania nanoparticle as tracer. This nanocomposite was fabricated by sequentially conjugating bovine serum albumin and horseradish peroxidase-labeled antibody onto the surface of titania nanoparticles using glutaraldehyde as the linkage. After a sandwich immuno-binding process, the captured nanocomposite tracer greatly catalyzed the luminol chemiluminescence reaction to produce a strong signal. Human IgG was detected as a model analyte, and a linear range of 0.5–200ngmL−1 was obtained. The detection limit of the proposed method was 0.1ngmL−1, which was 50-folds lower than that using the traditional tracer. The reproducibility, the stability and the specificity of the proposed immunoassay method were acceptable. The results for real sample analysis also demonstrated its application potential in some important areas such as clinical diagnosis. [Copyright &y& Elsevier]

Abstract: The permeation properties of hybrid inorganic–organic membrane with a silica crystalline framework are studied using quasi-non-equilibrium molecular dynamics. In particular the authors consider the single gas permeation of carbon dioxide and methane using the silica framework with phenyl groups inserted. The authors compare two types of membrane models, namely (a) single-pore with phenyl groups inserted (PSPM), and (b) single-pore without phenyl groups inserted (SPM) are developed. The pore diameter in the SPM model affects the performance of gas permeation. For the PSPM models the diameter significantly affects the selectivity; the optimum diameter is found to be 0.4nm. This leads to a carbon dioxide permeance of 2.87×10−4 molm−2 s−1 Pa−1, methane permeance of 1.66×10−5 molm−2 s−1 Pa−1 and a selectivity of 17.3. Finally based on the pore size two permeation mechanisms are analyzed from the atomic level and the effect of the number of phenyl groups (phenyl group pairs) in one type of membrane model is discussed. [Copyright &y& Elsevier]

Abstract: Continuous wave (cw) and pulsed high frequency electron paramagnetic resonance (HF-EPR) measurements were performed on an Fe-based magnetic cluster: Fe7O4(O2CPh)11(dmem)2, abbreviated Fe7. The cw EPR results show that two different molecular species exist in the crystal, with slightly different zero-field-splitting parameters. The spin decoherence time, T 2, was measured at high magnetic fields and low temperatures, which makes it possible to obtain high spin polarization and to significantly reduce decoherence due to electron spin flip-flop processes. Theoretical fitting of T 2 versus temperature shows that, for crystalline samples of this molecule, spin flip-flop fluctuations represent the main source of spin decoherence at low temperatures, as reported also for the Fe8 single-molecule magnet [Phys. Rev. Lett. 102 (2009) 087603]. Moreover, it is found that T 2 is position dependent within the EPR line, a model for which is given. We also note that this is the third example of an Fe-based cluster that exhibits a measurable decoherence time, and only the second involving a crystal. [Copyright &y& Elsevier]

Abstract: We report the high frequency electron paramagnetic resonance (HF-EPR) study of Cr3(dpa)4Cl2, a linear tri-atomic (Cr II ) 3 chain, that was reported to be EPR silent at the X-band (9.5GHz). Higher frequencies yield well resolved spectra for this S =2 system even at room temperature. At 30K, our variable frequency (34–400GHz) EPR spectra yield a large axial zero-field splitting (D) of −1.643(1)cm−1 as well as a small rhombic ZFS parameter E =0.0339(4)cm−1; with gx =1.9978(4), gy =1.9972(4), and gz =1.9808(4). The magnetic susceptibility measurements fully support the earlier magnetic susceptibility studies and the current EPR results. The observation of the EPR spectrum of only the S =2 state at room temperature suggests that the ground state is well isolated from the excited states. [Copyright &y& Elsevier]

One disadvantage of traditional permanent magnetic actuators (PMA) in vacuum circuit breakers (VCB) is that it is difficult to improve the velocity characteristics so that the interruption capacity of VCBs will be constrained. The objective of this paper is to propose a method for controlling PMAs to enhance the velocity characteristics. In contrast to the traditional control method that adopts only one coil in an opening or closing operation, the new method adopts both coils in the PMA simultaneously and controls the direction of the current in coils. Then a simulation model that involves coupled physical fields is constructed according to the new method. Moreover, the simulation results indicate that the initial velocity can be increased in the opening operation and the velocity characteristics in the closing operation can be optimized. In addition, the operating current can be reduced so that it is easy to control. Finally, experimental results validate the simulation results. [ABSTRACT FROM AUTHOR]

Abstract: Groundwater samples were collected in the Xiangjiang watershed in China from 2002 to 2008 to analyze concentrations of arsenic, cadmium, chromium, copper, iron, lead, mercury, manganese, and zinc. Spatial and seasonal trends of metal concentrations were then discussed. Combined with geostatistics, an ingestion risk assessment of metals in groundwater was performed using the dose-response assessment method and the triangulated irregular network (TIN) model. Arsenic concentration in groundwater had a larger variation from year to year, while the variations of other metal concentrations were minor. Meanwhile, As concentrations in groundwater over the period of 2002–2004 were significantly higher than that over the period of 2005–2007, indicating the improvement of groundwater quality within the later year. The hazard index (HI) in 2002 was also significantly higher than that in 2005, 2006, 2007 and 2008. Moreover, more than 80% of the study area recorded an HI of more than 1.0 for children, suggesting that some people will experience deleterious health effects from drinking groundwater in the Xiangjiang watershed. Arsenic and manganese were the largest contributors to human health risks (HHRs). This study highlights the value of long-term health risk evaluation and the importance of geographic information system (GIS) technologies in the assessment of watershed-scale human health risk. [Copyright &y& Elsevier]

The curing kinetics can influence the final macroscopic properties, particularly the three-point bending of the fiber-reinforced composite materials. In this research, the curing kinetics of commercially available glass fiber/epoxy resin prepregs were studied by non-isothermal differential scanning calorimetry (DSC). The curing kinetic parameters were obtained by fitting and the apparent activation energy Ea of the prepreg, the pre-exponent factor, and the reaction order value obtained. A phenomenological nth-order curing reaction kinetic model was established according to Kissinger equation and Crane equation. Furthermore, the optimal curing temperature of the prepregs was obtained by the T-β extrapolation method. A vacuum hot pressing technique was applied to prepare composite laminates. The pre-curing, curing, and post-curing temperatures were 116, 130, and 153 °C respectively. In addition, three-point bending was used to test the specimens' fracture behavior, and the surface morphology was analyzed. The results show that the differences in the mechanical properties of the samples are relatively small, indicating that the process settings are reasonable. [ABSTRACT FROM AUTHOR]