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• A dual-template strategy inspired by microbes is used to design carbon capsules. • Co 9 S 8 and CoF 2 synergically catalyze the sulfur conversion process. • The multiple active sites greatly boost Li-S cell performance. The intrinsic polysulfide shuttling and sluggish redox kinetics plague lithium-sulfur (Li-S) batteries with fast capacity fading and poor rate capability. Doping heteroatoms and embedding polar motifs into carbonaceous materials have been reckoned highly effective to promote both polysulfide trapping and catalytic sulfur conversion. Herein, we report polyaniline (PANi)-derived hierarchical carbon capsule co -doped with Co, S, N, F (MHCC) as the sulfur host, synthesized through a dual-template strategy exploiting Escherichia coli as the primary bio-template and ordered mesoporous silica as the secondary pore-forming template. The resulting capsular composite comprises a hollow core surrounded by a mesoporous shell, expressing a variety of active sites including Co-N x , Co 9 S 8 , and CoF 2 that synergistically boost the redox kinetics via strong chemisorption and catalytic effects. The Li-S cell with the sulfur/MHCC cathode delivers a high initial discharge capacity of 1331 mAh g−1 at 0.2 C and a long-term lifespan of 700 cycles at 2 C. Moreover, an areal capacity of 8.2 mAh cm−2 is achieved at a high sulfur loading of 8 mg cm−2. This study paves the way for the deployment of green Li-S batteries based on natural products through hierarchical structure design and catalytic engineering. [Display omitted] [ABSTRACT FROM AUTHOR]

In consideration of either fixed or variable gain relay scheme, end-to-end performance analysis of a dual-hop relay system over the asymmetric links composed of both radio-frequency (RF) and free-space optical (FSO) links with space time block coding (STBC) and two transmit antennas for the RF users is provided. In the analysis the RF links are modeled as the Rayleigh fading channel and the FSO link as the Gamma–Gamma fading channel with pointing errors. Closed-form expressions for the end-to-end outage probability (OP) and average symbol error probability (ASEP) in terms of the Meijer’s G functions are obtained. Based on the asymptotic expansion of the Meijer’s G function at high-SNR region, the asymptotic OP performance of the mixed RF/FSO systems with the fixed gain relay and misalignment FSO channels is discussed. Numerical simulations demonstrate that the system performance deteriorates when channel conditions become severe, and the RF users using STBC can achieve better communication quality than that of the regular RF users. In addition, the system with the fixed gain relay is better than that with the variable gain relay under the same average SNR in both the RF links and the FSO links. [ABSTRACT FROM AUTHOR]

Uncultivable microorganisms account for over 99% of all species on the planet, but their functions are yet not well characterized. Though many cultivable degraders for n-alkanes have been intensively investigated, the roles of functional n-alkane degraders remain hidden in the natural environment. This study introduces the novel magnetic nanoparticle-mediated isolation (MMI) technology in Nigerian soils and successfully separates functional microbes belonging to the families Oxalobacteraceae and Moraxellaceae , which are dominant and responsible for alkane metabolism in situ. The alkR -type n-alkane monooxygenase genes, instead of alkA- or alkP- type, were the key functional genes involved in the n-alkane degradation process. Further physiological investigation via a BIOLOG PM plate revealed some carbon (Tween 20, Tween 40 and Tween 80) and nitrogen (tyramine, l -glutamine and d -aspartic acid) sources promoting microbial respiration and n-alkane degradation. With further addition of promoter carbon or nitrogen sources, the separated functional alkane degraders significantly improved n-alkane biodegradation rates. This suggests that MMI is a promising technology for separating functional microbes from complex microbiota, with deeper insight into their ecological functions and influencing factors. The technique also broadens the application of the BIOLOG PM plate for physiological research on functional yet uncultivable microorganisms. [ABSTRACT FROM AUTHOR]

Nitrogen doping in carbon matrix can effectively improve the wettability of electrolyte and increase electric conductivity of carbon by ensuring fast transfer of ions. We synthesized a series of nitrogen-doped mesoporous carbons (CPANs) via in situ polymerization of polyacrylonitrile (PAN) in SBA-15 template followed by carbonization at different temperatures. Carbonization results in the formation of ladder structure which enhances the stability of the matrix. In this study, CPAN-800, carbon matrix synthesized by the carbonization at 800 °C, was found to possess many desirable properties such as high specific surface area and pore volume, moderate nitrogen content, and highly ordered mesoporous structure. Therefore, it was used to prepare S/CPAN-800 composite as cathode material in lithium sulfur (Li-S) batteries. The S/CPAN-800 composite was proved to be an excellent material for Li-S cells which delivered a high initial discharge capacity of 1585 mAh g −1 and enhanced capacity retention of 862 mAh g −1 at 0.1 C after 100 cycles. [ABSTRACT FROM AUTHOR]

Two groups of disymmetric Gemini imidazolium surfactants, [CCCim]Br ( m = 10, 12, 14) and [CCCim]Br ( m + n = 24, m = 12, 14, 16, 18) surfactants, were synthesized and their structures were confirmed by H NMR and ESI-MS spectroscopy. Their adsorption at the air/water interface, thermodynamic parameters and aggregation behavior were explored by means of surface tension, electrical conductivity and steady-state fluorescence. A series of surface activity parameters, including cmc, γ, π, p C, cmc/ C, Γ and A, were obtained from surface tension measurements. The results revealed that the overall hydrophobic chain length ( N) for [CCCim]Br and the disymmetry ( m/n) for [CCCim]Br had a significant effect on the surface activity. The cmc values decreased with an increase of N or m/n. The thermodynamic parameters of micellization (Δ G, Δ H, Δ S) derived from the electrical conductivity indicated that the micellization process of [CCCim]Br and [CCCim]Br was entropy-driven at different temperatures, but the contribution of Δ H to Δ G was enhanced by increasing N or m/n. The micropolarity and micellar aggregation number ( N) were estimated by steady-state fluorescence measurements. The results showed that the surfactant with higher N or m/n can form larger micelles, due to a tighter micellar structure. [ABSTRACT FROM AUTHOR]

The flash welded joint of U75V steel has been widely used in high-speed railway. Considering the fact that fatigue failure is the main failure mode of high-speed railway, ultrasonic peening treatment (UPT) was used to improve the fatigue performance of the flash welded joint. Micro-structure, hardness, wear resistance, corrosion resistance and fatigue fracture mechanism of the flash welded joint before and after UPT were analyzed in detail. Results show that nanocrystals form on the surface of the welded joint after UPT. Fatigue life, wear resistance and corrosion resistance of the welded joint were improved for the surface strengthening caused by UPT. [ABSTRACT FROM AUTHOR]

Two tetrasiloxane Gemini imidazolium surfactants with methylene spacer groups ([Si- s-Siim]Cl, s = 4, 6) were synthesized and characterized by H NMR and ESI-MS spectrum. The surface activity and thermodynamic properties in aqueous solution among three categories of surfactants, including [Si- s-Siim]Cl, the corresponding monomer ([Simim]Cl) and hydrocarbon-based Gemini imidazolium surfactant ([C-4-Cim]Cl), were compared by surface tension and electrical conductivity methods. A series of surface activity parameters, including cmc, γ, π, pc, Γ and A, and the adsorption isotherms were obtained from the surface tension plots. The results indicated that the tetrasiloxane Gemini imidazolium surfactant with the longer spacer group has the higher capacity to form micelles but lower efficiency to reduce surface tension. Besides, the cmc value of [Si- s-Siim]Cl was about one order of magnitude lower than that of [Simim]Cl. The tetrasiloxane-based surfactants have the higher capacity to low the surface tension than the hydrocarbon-based surfactant. The adsorption isotherms of the tetrasiloxane-based surfactants are similar to those of conventional hydrocarbon-based surfactants. The thermodynamic parameters of micellization process, namely, the standard Gibbs free energy ( ΔG), enthalpy ( ΔH) and entropy ( ΔS) originated from the electrical conductivity measurements at five different temperatures, suggested that the micellization of [Si- s-Siim]Cl and [C-4-Cim]Cl is entropy-driven process whereas aggregation of [Simim]Cl is enthalpy-driven process at the whole investigated temperatures. The dynamic light scattering results indicate that the aggregation size of [Si-4-Siim]Cl (113.6 nm) is larger than [Si-6-Siim]Cl (101.7 nm). [ABSTRACT FROM AUTHOR]

We investigate the problem of multi-view human gait recognition along any straight walking paths. It is observed that the gait appearance changes as the view changes while certain amount of correlated information exists among different views. Taking advantage of that type of correlation, a multi-view gait recognition method is proposed in this paper. First, we estimate the viewing angle of the monitor equipment in terms of the probe subject. To this end, our method considers this as a classification problem, where the classification signals are the viewing angles, and the classification features are the elements of the transformation matrix that is estimated by the Transformation Invariant Low-Rank Texture (TILT) algorithm. Then, the gallery gait appearances are converted to the view of the probe subject using the proposed Appearance Conversion Machine (ACM), where the gait features of the spatially neighbouring pixels of the gait feature are considered as the correlated information of the two views. In the end, a similarity measurement is applied on the converted gait appearance and the testing gait appearance. Experiments on the CASIA-B multi-view gait database show that the proposed gait recognition method outperforms the state-of-the-art under most views. [ABSTRACT FROM AUTHOR]

This study developed Fe 3 O 4 @cellulose nanocomposites by co-precipitation synthesis for bacteria capture and isolation. By surface modification with cellulose, the Fe 3 O 4 @cellulose nanocomposites have 20 nm average particle size and 3.3–24.9 emu/g saturation magnetization. Living bacteria could be captured by the Fe 3 O 4 @cellulose nanocomposites and harvested by magnetic field, with high efficiency (95.1%) and stability (>99.99%). By metabolizing cellulose and destroying the Fe 3 O 4 @cellulose@bacteria complex, cellulose-decomposing microorganisms lost the magnetism. They were therefore able to be isolated from the inert microbial community and the separation efficiency achieved over 99.2%. This research opened a door to cultivate the uncultivable cellulose-decomposing microorganisms in situ and further characterize their ecological functions in natural environment. [ABSTRACT FROM AUTHOR]

Pedestrian detection is an important image understanding problem with many potential applications. There has been little success in creating an algorithm which exhibits a high detection rate while keeping the false alarm in a relatively low rate. This paper presents a method designed to resolve this problem. The proposed method uses the Kinect or any similar type of sensors which facilitate the extraction of a distinct foreground. Then potential regions, which are candidates for the presence of human(s), are detected by employing the widely used Histogram of Oriented Gradients (HOG) technique, which performs well in terms of good detection rates but suffers from significantly high false alarm rates. Our method applies a sequence of operations to eliminate the false alarms produced by the HOG detector based on investigating the fine details of local shape information. Local shape information can be identified by efficient utilization of the edge points which, in this work, are used to formulate the so called Shape Context (SC) model. The proposed detection framework is divided in four sequential stages, with each stage aiming at refining the detection results of the previous stage. In addition, our approach employs a pre-evaluation stage to pre-screen and restrict further detection results. Extensive experimental results on the dataset created by the authors, involves 673 images collected from 11 different scenes, demonstrate that the proposed method eliminates a large percentage of the false alarms produced by the HOG pedestrian detector. [ABSTRACT FROM AUTHOR]

The α-titanium alloy was treated through ultrasonic surface rolling process at room temperature. Nanocrystalline was obtained in specimen surface. It is newly discovered that a fixed crystal orientation of (120) exists between nanocrystalline zone and matrix zone. The nano-enhancing mechanism of ultrasonic surface rolling process can be explained by the change of twins and crystal orientation. The compress twinning {10−12}〈−1011〉 of α-titanium dominates the deformation during rolling and impacting. [ABSTRACT FROM AUTHOR]

Enzyme-catalyzed synthesis of several fatty acyl-amino acid esters based on d -galactose, as well as their chemical evaluation, was performed. These novel galactosyl fatty acyl-amino acid monoesters were synthesized by utilizing lipase from lipozyme TL IM in tert -butanol with d -galactose and fatty acyl-amino acids as starting materials. The products were characterized by 1 H NMR, 13 C NMR and MS analysis. In addition, their primary physical properties, such as hydrophilic-lipophilic balance (HLB), critical micellar concentration (CMC), solubility in water, maximum surface excess (Γ max ), and minimal surface tension ( A min ) were measured. The experimental results showed that their CMC values are between 5 and 0.4 mM. The HLB values of galactosyl esters 15 – 17 indicate that they are useful as oil-in-water emulsions or detergents, whereas 18 – 22 can be employed as water-in-oil emulsifiers or wetting agents. [ABSTRACT FROM AUTHOR]

Nowadays, U75V steel is widely used in high speed railway construction, and commonly jointed by means of flash butt welding procedure. Considering the fact that fatigue failure is the main failure mode of railways, to ensure an adequate service life of railways, especially railways in coastal areas, this work mainly investigated the fatigue fracture mechanism of flash butt welding joints of U75V rail steel. First, the flash butt welding joints were prepared under two sets of process parameters and certain welding joints were corroded beforehand. Then, the microstructure, hardness, S – N curve and fatigue fracture of welding joints were analyzed in detail. Finally, the fracture mechanism was comprehensively discussed by considering the effect of welding parameters. It was concluded that the fatigue performance of flash welding joint is mainly determined by the upset pressure. Higher upset pressure is conducive to improve the fatigue strength. The fatigue crack source of fractured specimens under the condition of corrosion environment is at interface area and at the subsurface of sample. Meanwhile, the corrosion fatigue life obviously reduces. [ABSTRACT FROM AUTHOR]

Meat analogs produced by high moisture extrusion (HME) are considered to be one of the products that have great potential for replacing real meat. The key issue as a meat analog is whether the texture can meet the standards of real meat. Nowadays, there have been some advances in the textural characterization of meat analogs, which are discussed in detail in this review. Firstly, this review describes the current characterizations of meat analogs in terms of fiber structure, hardness, springiness, tensile resistant force and sensory evaluation. Then, methods for analyzing the texture of meat analogs, such as texture analyzer, microstructure‐based methods, and other methods for characterizing fiber structure, are summarized. In addition, these characterizations are discussed in relation to the factors that influence the texture of meat analogs during HME. Finally, we propose priorities and some promising methods for future meat analogs conformation studies. [ABSTRACT FROM AUTHOR]

Atmospheric turbulence seriously degrades the performance of free space optical (FSO) communication systems, especially the coupling efficiency. In this paper, we propose a stochastic parallel gradient descent (SPGD) algorithm to compensate the atmospheric turbulence in FSO communication system. Theoretical analysis and work flow of the algorithm are given. Both simulation and experimental results indicate that the coupling efficiency can be increased from 12% to more than 80% after 270 iterations or more than threefold, which implies a significant improvement of the performance. [ABSTRACT FROM AUTHOR]

Sulfur composite material with a highly porous carbon sphere as the conducting container was prepared. The highly porous carbon sphere was easily synthesized with resorcinol-formaldehyde precursor as the carbon source. The morphology of the carbon was observed with field emission scanning electron microscope and transmission electron microscope, which showed a well-defined spherical shape. Brunauer-Emmett-Teller analysis indicated that it possesses a high specific surface area of 1563m2g-1 and a total pore volume of 2.66cm3g-1 with a bimodal pore size distribution, which allow high sulfur loading and easy transportation of lithium ions. Sulfur carbon composites with varied sulfur contents were prepared by melt-diffusion method and lithium sulfur cells with the sulfur composites showed improved cyclablity and long-term cycle life. [ABSTRACT FROM AUTHOR]

Sulfur composite was prepared by encapsulating sulfur into CMK-3 mesoporous carbon with different heating times and then used as the cathode material for lithium sulfur batteries. Thermal treatment at 300°C plays an important role in the sulfur encapsulation process. With 20h of heating time, a portion of sulfur remained on the surface of carbon, whereas with 60h of heating time, sulfur is confined deeply in the small pores of carbon that cannot be fully exploited in the redox reaction, thus causing low capacity. The S/CMK-3 composite with thermal treatment for 40h at 300°C contained 51.3wt.% sulfur and delivered a high initial capacity of 1375mAhg-1 at 0.1C. Moreover, it showed good capacity retention of 704mAhg-1 at 0.1C and 578mAhg-1 at 2C even after 100 cycles, which proves its potential as a cathode material for high capability lithium sulfur batteries. [ABSTRACT FROM AUTHOR]

A series of gel polymer electrolytes (GPEs) based on electrospun membranes of poly(vinylidene fluoride-co-hexafluoropropylene) [P(VdF-co-HFP)] incorporating room temperature ionic liquids (RTILs), 1-alkyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide complexed with lithium bis(trifluoromethylsulfonyl)imide (LiTFSI) as electrolytes have been prepared and their fundamental electrochemical properties were investigated. The morphology of electrospun membranes was examined by a field emission scanning electron microscope (FE-SEM). The membranes show uniform morphology with an average fiber diameter of 780nm, high porosity and high electrolyte uptake. GPEs were prepared by soaking the electrospun membranes in 1M LiTFSI in RTILs for 1h and exhibit a high ionic conductivity of 2.4×10−3–4.5×10−3 Scm−1 at 25°C. A Li/GPEs/LiFePO4 cell using these RTILs delivers high discharge capacity (~140mAh g−1) when evaluated at 25°C at 0.1C-rate and exhibits a very stable discharge capacity under continuous cycling. Among the GPEs, EMITFSI shows the highest electrochemical properties although the solid electrolyte interface (SEI) layer was not formed. [ABSTRACT FROM AUTHOR]

During discharge of lithium sulfur (Li-S) battery with a liquid electrolyte system, sulfur is first reduced to Li2S8, which is dissolved into the organic electrolyte and this serves as the liquid cathode. In solution, lithium polysulfides undergo a series of chemical reactions and their concentration varies during cell reaction. The amount of sulfur and electrolytes in the system plays an important role in determining the cell performance. In this work, the effect of sulfur loading in cathode and the amount of electrolyte on the energy density and cycle performance of Li-S battery has been investigated. Cathodes with sulfur loading of 0.99, 2.98, and 6.80 mg_S cm−2 were prepared. Precisely controlled amount of electrolyte was added with varied electrolyte/sulfur (E/S) ratios of 1.67, 5, 10, 20, and 40 µl /mg_S. The surface morphology of fresh and cycled sulfur cathodes was characterized using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). [ABSTRACT FROM AUTHOR]

Lectin receptor-like kinases (LecRLKs) belong to the large subfamily of receptor like kinases (RLKs), which play a critical role in plant development and innate immunity. However, knowledge about the LecRLKs in sweet cherry and its function to against adverse environmental stresses are lacking. In this study, we identified 161 PaLecRLKs genes in the genome of sweet cherry. Phylogenetic analysis showed that PaLecRLKs proteins can be divided into three types, including L -type (50), G-type (110), and C-type (1). Analysis of gene expression patterns showed that most of the L -type PaLecRLKs genes were highly expressed under biotic and abiotic stresses. Functional study found that overexpression PaLectinL16 in Arabidopsis could enhance its resistance with abiotic (salt, drought) stresses. Moreover, PaLectinL16 overexpression also improved the salt tolerance of transgenic sweet cherry rootstock Gisela 6 through increasing the activities of ROS scavenging enzymes and up-regulation the related genes. This study offers a comprehensive view of PaLecRLKs in sweet cherry and sheds light on potential roles with external environmental stresses. • 161 PaLecRLKs genes have been found in the genome of sweet cherry, including 110G-type, 50 L -type and 1C-type. • Overexpression PaLectinL16 in Arabidopsis enhanced its resistance with drought and salt stresses. • Overexpression PaLectinL16 in sweet cherry Gisela 6 roots improved its salt tolerance. [ABSTRACT FROM AUTHOR]

In this paper, the effects of nitrogen doping and oxygen vacancies on thermoelectric properties of Pt/N-doped ITO thin film thermocouples were discussed in detail from the perspective of thermodynamics and kinetics based on first-principles and experiments. The atomic structure and bonding characteristics of ITO and N-doped ITO were investigated by X-ray diffraction and X-ray photoelectron spectroscopy. The calculation results show that nitrogen doping makes the charge transfer to the Sn-N bond and produces anti-bonding states to the nearest neighbor Sn–O bond, so that the repair of oxygen vacancies in N-doped ITO requires a higher activation energy than ITO. The effects of band structure, carrier concentration and carrier effective mass on the Seebeck coefficients of ITO and N-doped ITO were further discussed in detail. Finally, Pt/ITO and Pt/N-doped ITO thin film thermocouples were fabricated on the Al2O3 substrates by magnetron sputtering to verify their thermoelectric stability. The calibration results also proved that N-doped ITO has higher thermoelectric stability than ITO. [ABSTRACT FROM AUTHOR]

An image segmentation method is proposed based on exploiting the spatial patterns in synthetic aperture radar (SAR) images. First, a similarity map is constructed for evaluating the similarity between the spatial pattern of the SAR image and the reference clutter images. Then, a segmentation threshold is selected based on the similarity map. Finally, image segmentation is achieved by preserving pixels that have larger similarity values. The superiority of the proposed method is verified by the experimental results for high‐resolution SAR images. [ABSTRACT FROM AUTHOR]

The construction of Euler fluxes is an important step in shock-capturing/upwind schemes. It is well known that unsuitable fluxes are responsible for many shock anomalies, such as the carbuncle phenomenon. Three kinds of flux vector splittings (FVSs) as well as three kinds of flux difference splittings (FDSs) are evaluated for the shock instability by a fifth-order weighted compact nonlinear scheme. The three FVSs are Steger–Warming splitting, van Leer splitting and kinetic flux vector splitting (KFVS). The three FDSs are Roe's splitting, advection upstream splitting method (AUSM) type splitting and Harten–Lax–van Leer (HLL) type splitting. Numerical results indicate that FVSs and high dissipative FDSs undergo a relative lower risk on the shock instability than that of low dissipative FDSs. However, none of the fluxes evaluated in the present study can entirely avoid the shock instability. Generally, the shock instability may be caused by any of the following factors: low dissipation, high Mach number, unsuitable grid distribution, large grid aspect ratio, and the relative shock-internal flow state (or position) between upstream and downstream shock waves. It comes out that the most important factor is the relative shock-internal state. If the shock-internal state is closer to the downstream state, the computation is at higher susceptibility to the shock instability. Wall-normal grid distribution has a greater influence on the shock instability than wall-azimuthal grid distribution because wall-normal grids directly impact on the shock-internal position. High shock intensity poses a high risk on the shock instability, but its influence is not as much as the shock-internal state. Large grid aspect ratio is also a source of the shock instability. Some results of a second-order scheme and a first-order scheme are also given. The comparison between the high-order scheme and the two low-order schemes indicates that high-order schemes are at a higher risk of the shock instability. Adding an entropy fix is very helpful in suppressing the shock instability for the two low-order schemes. When the high-order scheme is used, the entropy fix still works well for Roe's flux, but its effect on the Steger–Warming flux is trivial and not much clear. [ABSTRACT FROM PUBLISHER]

Highlights: [•] The slope of S–N curve of electron beam welding joint was revised. [•] Tensile properties and microstructure of beam welding joints were studied. [•] Fatigue failure mechanism of electron beam welding joint was studied. [Copyright &y& Elsevier]

Highlights: [•] The approximation K-singular value decomposition algorithm with nonnegative constraint is used to train PSD dictionary. [•] The least angle regression algorithm with a new termination rule is applied to obtain the sparse representation. [•] The termination rule is related to the noise level and nonzero cross terms of the speech and noise spectra. [•] The enhanced speech signal is obtained by using the estimated PSD and subspace approach. [Copyright &y& Elsevier]

Abstract: Ultrasonic surface rolling process (USRP) is a novel surface nanocrystallization technique based on severe plastic deformation (SPD). The combination of static extrusion and dynamic impact generates intensive plastic deformation, which leads to the strengthening of the material surface. The present paper aims to investigate the mechanical properties of material surface after USRP. For this purpose, nano-indentation tests were adopted to obtain the load P and penetration depth h. Dimensional analysis of test results (P–h curves) was then performed for determining the microplasticity of the treated material locally. The values of yield strength and strain hardening exponent of the surface layer were calculated and verified by finite-element simulation. Good agreement was obtained between experimental curves and simulated ones. The microstructural evolution of the surface treated by USRP was discussed to interpret the mechanism of surface strengthening. Finally, effects of USRP parameters including static force, vibration amplitude and repeated processing numbers on the variation of plastic parameters in the surface layer were discussed. [Copyright &y& Elsevier]

Highlights: [•] The new prolong life method of MSF about welded joint was put forward. [•] The low transformation temperature alloy powder was applied to the method of MSF. [•] The fatigue strength of LTT-joint increases by 74.07%. [ABSTRACT FROM AUTHOR]

PRDM9 directs human meiotic crossover hot spots to intergenic sequence motifs, whereas budding yeast hot spots overlap regions of low nucleosome density (LND) in gene promoters. To investigate hot spots in plants, which lack PRDM9, we used coalescent analysis of genetic variation in Arabidopsis thaliana. Crossovers increased toward gene promoters and terminators, and hot spots were associated with active chromatin modifications, including H2A.Z, histone H3 Lys4 trimethylation (H3K4me3), LND and low DNA methylation. Hot spot-enriched A-rich and CTT-repeat DNA motifs occurred upstream and downstream, respectively, of transcriptional start sites. Crossovers were asymmetric around promoters and were most frequent over CTT-repeat motifs and H2A.Z nucleosomes. Pollen typing, segregation and cytogenetic analysis showed decreased numbers of crossovers in the arp6 H2A.Z deposition mutant at multiple scales. During meiosis, H2A.Z forms overlapping chromosomal foci with the DMC1 and RAD51 recombinases. As arp6 reduced the number of DMC1 or RAD51 foci, H2A.Z may promote the formation or processing of meiotic DNA double-strand breaks. We propose that gene chromatin ancestrally designates hot spots within eukaryotes and PRDM9 is a derived state within vertebrates. [ABSTRACT FROM AUTHOR]

Abstract: The current business environment changes rapidly, dictated by user requirements and market opportunities. Organisations are therefore driven to continuously adapt their business processes to new conditions. Thus, management of business process schema evolution, particularly process version control, is in great demand to capture the dynamics of business process schema changes. This paper aims to facilitate version control for business process schema evolution, with an emphasis on version compatibility, co-existence of multiple versions and dynamic version shifts. A multi-level versioning approach is established to specify dependency between business process schema evolutions, and a novel version preserving graph model is proposed to record business process schema evolutions. A set of business process schema updating operations is devised to support the entire set of process change patterns. By maintaining sufficient and necessary schema and version information, our approach provides comprehensive support for navigating process instance executions of different and changing versions, and deriving the process schema of a certain version. A prototype is also implemented for the proof-of-concept purpose. [Copyright &y& Elsevier]

Highlights: [•] A ternary sulfur/polyaniline–carbon black composite is prepared with a two-step thermal treatment. [•] A polyaniline–carbon black composite is applied as a conducting container for housing sulfur. [•] Polyaniline promotes the contact of sulfur and carbon black and contributes to the polysulfides confinement. [•] The sulfur/polyaniline–carbon black composite as cathode material exhibits improved cycle performance and rate capability. [ABSTRACT FROM AUTHOR]

[Display omitted] • An organosulfur cathode was synthesized with a thiol-coordinated single crystal. • The charge redistribution mechanism promoted the polysulfide trapping. • The organosulfur cells achieved fast reaction kinetics and ultralong cycle life. Currently, the urgent requirement of high-energy–density storage devices for large-grid applications has been brought to public attention. Lithium-sulfur (Li-S) batteries are one of the most recognized candidates to substitute for the state-of-the-art lithium-ion (Li-ion) batteries. To conquer the dogged polysulfide shuttling in Li-S cells, a supramolecular crystal was synthesized via the coordination of a thiol ligand with nickel to generate a unique cage-like cluster in the form of N 4 -Ni∙∙∙Ni-S 4 as the precursor of organosulfur, in which sulfur was anchored on nitrogen sites. The organosulfur undergoes changes in both the configuration and electron distribution upon lithiation/delithiation process, which can strengthen entrapment of polysulfides, boost efficient sulfur conversion and promote the reaction kinetics of the cathodes. The Li-S cells were demonstrated a high initial discharge capacity of 1354.9 mAh g−1 at 0.2 C and a long-term lifespan of 1000 cycles at 2 C. The high-loading sulfur cathodes of 8.6 mg cm−2 is capable of delivering an areal capacity as high as 9.1 mAh cm−2. Combining with the advantages of low cost and facile synthesis, such organosulfur is of great promising perspective in further boosting the commercial realization of Li-S batteries. [ABSTRACT FROM AUTHOR]

A major challenge in cardiovascular regenerative medicine is the development of novel therapeutic strategies to restore the function of cardiac muscle in the failing heart. The heart has historically been regarded as a terminally differentiated organ that does not have the potential to regenerate. This concept has been updated by the discovery of cardiac stem and progenitor cells that reside in the adult mammalian heart. Whereas diverse types of adult cardiac stem or progenitor cells have been described, we still do not know whether these cells share a common origin. A better understanding of the physiology of cardiac stem and progenitor cells should advance the successful use of regenerative medicine as a viable therapy for heart disease. In this review, we summarize current knowledge of the various adult cardiac stem and progenitor cell types that have been discovered. We also review clinical trials presently being undertaken with adult stem cells to repair the injured myocardium in patients with coronary artery disease. [ABSTRACT FROM AUTHOR]

Abstract: Magnesium doped Li1−2x Mg x FePO4/C (x =0.00, 0.01, 0.03, 0.05) cathode materials were synthesized by sol–gel method, and the effect of magnesium doping as well as its content on the electrochemical properties for lithium batteries was also investigated. Their morphology was studied with field emission scanning electron microscope and Li1−2x Mg x FePO4 materials showed the olivine phase without impurities. The thin carbon layer of Li1−2x Mg x FePO4/C was confirmed by high resolution transmission electron microscopy. The magnesium doped Li1−2x Mg x FePO4/C particles were smaller than those undoped. The Li1−2x Mg x FePO4/C materials showed better cycling behavior than undoped LiFePO4, especially at high C-rate in which Li0.94Mg0.03FePO4/C composition exhibited the best electrochemical properties. [Copyright &y& Elsevier]

The composition and microstructure of sandwich structure Al 2 O 3 /Si 3 N 4 /YAlO multilayer films deposited by magnetron sputtering were investigated. The results of X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDS) show that α-SiAlON and Y-doped α-SiAlON are formed at the interface of Al 2 O 3 /Si 3 N 4 and Si 3 N 4 /YAlO respectively after nitrogen annealing at 1300 °C. The thermoelectric properties of S-type (Pt/Pt–10%Rh) thin film thermocouples (TFTCs) with Al 2 O 3 and Al 2 O 3 /Si 3 N 4 /YAlO protective layers deposited by magnetron sputtering were investigated from 700 °C to 1550 °C. The high temperature static calibration results show that the thermoelectric performance of TFTCs with an Al 2 O 3 protective layer begins to decline at 1350 °C, the drift rate of the TFTCs is 13.27 °C/h, and the TFTCs fail at 1550 °C. However, the drift rate of TFTCs with an Al 2 O 3 /Si 3 N 4 /YAlO protective layer is only 2.19 °C/h at 1350 °C, and the performance begins to decline significantly at 1550 °C with a drift rate of 82.89 °C/h. The S-type TFTCs with sandwich structure Al 2 O 3 /Si 3 N 4 /YAlO multilayer provides a good prospect for the application of TFTCs in ultra-high temperature environment. [ABSTRACT FROM AUTHOR]

Abstract: The fatigue properties of EH36 steel and butt welds ground flush in the super-long life regime were studied in this paper. Experimental results indicate that fatigue fracture may still occur during 108–1010 cycles, which is incompatible with conventional method of using the fatigue strength corresponding to 1×107 cycles to design welding structure serving in the super-long life regime. Scanning electron microscope analysis shows that fatigue crack mainly initiates from internal defects in the fusion face for butt welds ground flush. A new kind of “fish-eye” is found in welded joints. The relation between fatigue life and area of defects in the butt welds ground flush is confirmed. [Copyright &y& Elsevier]

Abstract: Modification of spray fusing (MSF), which is a new method, was used to improve the fatigue strength of welded joints. Cruciform welded joint of Q235B steel was processed by MSF with nickel-base alloy powder of Ni60A and Ni25A. The bonding layer between coating and weld was studied by optical microscopy, scanning electron microscopy (SEM) and energy spectrum analysis. The results show that flame spray fusing can produce a coating layer with finer microstructure, lower impurities content, less air hole and higher bonding strength. Stress concentration at weld toe was significantly reduced due to smooth coating of high curvature after MSF. High cycle fatigue test results indicate that fatigue strength of welded joint spray fused by Ni60A is higher than that of welded joint spray fused by Ni25A owing to the good effect of MSF. Low cycle fatigue test results show that fatigue life of welded joint spray fused by Ni25A dose not affected by the poor effect of MSF compared with welded joint spray fused by Ni60A. [Copyright &y& Elsevier]

Web service and business process technologies are widely adopted to facilitate business automation and collaboration. Given the complexity of business processes, it is a sought-after feature to show a business process with different views to cater for the diverse interests, authority levels, etc., of different users. Aiming to implement such flexible process views in the Web service environment, this paper presents a novel framework named FlexView to support view abstraction and concretisation of WS-BPEL processes. In the FlexView framework, a rigorous view model is proposed to specify the dependency and correlation between structural components of process views with emphasis on the characteristics of WS-BPEL, and a set of rules are defined to guarantee the structural consistency between process views during transformations. A set of algorithms are developed to shift the abstraction and concretisation operations to the operational level. A prototype is also implemented for the proof-of-concept purpose. [ABSTRACT FROM AUTHOR]

Abstract: Contrast fatigue tests were carried out on T-shape tubular joints of 20 steel in three conditions: as welded, treated by ultrasonic peening treatment (UPT) before loading and UPT under loading. Results are: (1) Dispersity of test results measured by nominal stress is much larger than that measured by hot spot stress. After UPT before loading, fatigue strength of 20 steel tubular joints measured by hot spot stress increases by 67% and fatigue life is prolonged by 22–45 times. (2) Under low stress ratio R, UPT before loading can improve the fatigue performance of welded tubular joints significantly. (3) Under high stress ratio R, UPT under loading (static load) is recommended to improve the fatigue performance of welded tubular joints. UPT under loading not only enhances the fatigue properties at low stress level, but also at high stress level. (4) The general rule of S–N curves of welded joints treated by UPT is commonly effected by external load (static load) and self release of residual stress. [Copyright &y& Elsevier]

Abstract: Apart from PEO based solid polymer electrolytes, tailor-made gel polymer electrolytes based on blend/composite membranes of poly(vinylidene fluoride-co-hexafluoropropylene) and polyacrylonitrile are prepared by electrospinning using 14wt% polymer solution in dimethylformamide. The membranes show uniform morphology with an average fiber diameter of 320–490nm, high porosity and electrolyte uptake. Polymer electrolytes are prepared by soaking the electrospun membranes in 1M lithium hexafluorophosphate in ethylene carbonate/dimethyl carbonate. Temperature dependent ionic conductivity and their electrochemical performance are studied. The blend/composite polymer electrolytes show good ionic conductivity in the range of 10−3 Scm−1 at ambient temperature and good electrochemical performance. All the Polymer electrolytes show an anodic stability >4.6V with stable interfacial resistance with storage time. The prototype cell shows good charge–discharge properties and stable cycle performance with comparable capacity fade compared to liquid electrolyte under the test conditions. [Copyright &y& Elsevier]

Abstract: Background: Endothelial progenitor cells (EPCs) can be mobilized by cytokines and recruited to sites of neovascularization and neointima, where they differentiate into mature endothelial cells. It is thought that stromal cell-derived factor-1α (SDF-1α) is involved in ischemia-mediated mobilization and homing of EPCs and in vascular injury-mediated mobilization and homing of vascular smooth muscle progenitor cells. It is unclear if SDF-1α plays a similar role in the mobilization and recruitment of EPCs after vascular injury. Methods and Results: SDF-1α was detected by reverse transcriptase–polymerase chain reaction and Western blot in the carotid arteries of mice at different times after wire-induced injury. SDF-1α expression was evident at 1 day and peaked at 3 days after arterial injury. In an ELISA test, a rise in the plasmatic concentration of SDF-1α and a significant reduction of SDF-1α bone marrow (BM) concentration were noticed at different times after injury (Days 1, 3, and 7). Fluorescence-activated cell sorting analysis revealed that the amount of circulating EPCs was increased shortly after induction of vascular injury and persisted for up to 7 days. In SDF-1α antibody-treated mice, only a small rise in the amount of circulating EPCs was noted at 1 day. En-face microscopy and immunohistochemical analysis showed that systemic injection of EPCs after vascular injury demonstrated their recruitment to the sites of endothelial denudation, where they could adopt an endothelium-like phenotype and accelerate reendothelialization of the injured arteries. Fewer CXCR4 (receptor of SDF-1)-blocked EPCs could home to the sites of endothelial denudation, and accelerated reendothelialization was not observed in this group. Treatment of mice after carotid injury with a neutralizing SDF-1α monoclonal antibody for 2 weeks reduced reendothelialization area. Conclusion: We demonstrated for the first time that SDF-1α plays an important role in reendothelialization after vascular injury in mice. This contribution appears to be attributable to SDF-1α-dependent mobilization and recruitment of circulating EPCs. [Copyright &y& Elsevier]

Abstract: CD30-positive anaplastic large cell lymphoma (ALCL) is a distinctive malignant large cell lymphoma of T-cell lineage, often presenting in lymph node or extranodal sites. ALCL cases with extensive bone marrow and peripheral blood involvement manifested as “leukemic phase” are extremely rare and the most of those cases reported are anaplastic large cell lymphoma kinase (ALK) positive ALCL in childhood population. Here we report four adult cases of ALK-negative ALCL with extensive bone marrow and peripheral blood involvement manifested as “leukemic phase”. Circulating large lymphoma cells varied from 20 to 80% in peripheral blood and bone marrow biopsy showed various nodular or interstitial infiltrates. By reviewing the clinicopathologic data of previously reported ALCL cases with extensive bone marrow and peripheral blood involvement, there appears to be of large variations in regard to the patient''s age, morphologic variants, immunophenotypic or genotypic characteristics of the disease. While most cases of ALCL with peripheral blood and bone marrow involvement were ALK-positive or carrying t(2;5) translocation, rare ALK-negative cases were also present. Leukemic ALCL patients usually have unfavourable prognosis, regardless of ALK expression. [Copyright &y& Elsevier]

Abstract: The synthesis, characterization and electrochemical properties of poly(vinylidene fluoride-co-hexafluoropropylene) {P(VdF-co-HFP)} prepared by electrospinning and phase inversion methods are reported. The morphologies of the membranes were studied by field emission scanning electron microscope and atomic force microscope. Thermal properties of the membranes were evaluated by differential scanning calorimetry. The resultant porous membranes are good absorbents of liquid electrolytes and exhibit high electrolyte retention capacity. The polymer electrolytes were prepared by soaking the membranes in liquid electrolyte. The temperature dependent ionic conductivity and electrochemical properties were evaluated. Li/LiFePO4 cell with electrospun membrane delivers a discharge capacity of 145mAh/g, which corresponds to 85% utilization of active material under the test conditions and shows lower capacity fade under continuous cycling. [Copyright &y& Elsevier]

Abstract: In view of the safety concerns and the requirements of high energy density lithium batteries, the room temperature ionic liquids (RTILs) are being investigated as suitable candidates to substitute organic electrolytes in polymer electrolytes. In this article, we report synthesis, characterization, and electrochemical properties of nanocomposite polymer electrolytes (NCPEs) comprising of a RTIL [n-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (BMITFSI)] and nano-sized ceramic fillers (SiO2, Al2O3 or BaTiO3) hosted in electrospun poly(vinylidene fluoride-co-hexafluoropropylene) [P(VdF-HFP)] membranes. The addition of BMITFSI and ceramic fillers in polymer electrolytes results in high ionic conductivity at room temperature. The cells prepared with BMITFSI and different NCPEs show good interfacial stability and oxidation stability at >5.5V with the highest value of 6.0V for the NCPE incorporating BaTiO3. The cell with the NCPE containing BaTiO3 delivers high initial discharge capacity of 165.8mAhg−1, which corresponds to 97.5% utilization of active material under the test conditions, and showed the least % capacity fade after prolonged cycling. [Copyright &y& Elsevier]

A feature processing technique that is specifically designed for synthetic aperture radar images, where features are extracted with merits of compactness, high discrimination ability, and shift invariance is proposed. To this end, a rich feature set is first constructed with a wealth of discrimination information. Then, the redundancy and dimensionality of the rich feature set are reduced such that a much more compact and efficient feature set can be achieved. Finally, the advantages of the compact feature set are further explored by learning the relationships among features statistically in discriminative fashion. Experimental results show the efficiency of the proposed method. [ABSTRACT FROM AUTHOR]

In HCl-NaAc buffer medium of pH 3.25 ∼ 3.85, when tolterodine tartrate (TDT) reacted with alizarin green (AG) by electrostatic force and hydrophobic force to form an ion-association complex, the resonance Rayleigh scattering (RRS) intensity could be enhanced greatly, and a new RRS spectrum appeared. The maximum RRS peak was at 344 nm, and the other RRS peak was located at 454 nm. Under optimum conditions, there is a linear relationship between the RRS intensity and TDT concentration in the range of 7.06 × 10-7 to about 3.12 × 10-5 mol/L. The method is very sensitive, and the detection limit (3σ/K) for tolterodine tartrate is 3.31 × 10-7 mol/L. The optimum reaction conditions and influence factors were investigated. A highly sensitive, simple, and fast method is proposed for the determination of TDT. [ABSTRACT FROM AUTHOR]

Abstract: A series of nanocomposite polymer electrolytes (NCPEs) comprising nanoparticles of BaTiO3, Al2O3 or SiO2 were prepared by electrospinning technique. The nano-sized ceramic fillers were incorporated into poly(vinylidene fluoride-co-hexafluoropropylene) [P(VdF-HEP)] membranes during the electrospinning process. The resultant porous membranes are good absorbent of the liquid electrolyte and exhibit high electrolyte retention capacity. The presence of the ceramic nanoparticles has positive effect on the mechanical properties of the membranes. The ionic conductivity and the electrochemical stability window of the electrospun P(VdF-HFP)-based polymer are enhanced by the presence of the fillers. The cell Li/LiFePO4 based on the NCPE containing BaTiO3 delivers a discharge capacity of 164mAh/g, which corresponds to 96.5% utilization of the active material. In comparison, the performance of Li/LiFePO4 cells with NCPEs containing Al2O3 and SiO2 was observed to be lower with respective discharge capacities of 153 and 156mAh/g. The enhanced performance of the BaTiO3-based-NCPE is attributed mainly to its better interaction with the host polymer and compatibility with lithium metal. [Copyright &y& Elsevier]

RNA modification is a type of post-transcriptional modification that regulates important cellular pathways, such as the processing and metabolism of RNA. The most abundant form of methylation modification is RNA N6-methyladenine (m6A), which plays various post-transcriptional regulatory roles in cellular biological functions, including cell differentiation, embryonic development and disease occurrence. Bones play a pivotal role in the skeletal system as they support and protect muscles and other organs, facilitate movement and ensure haematopoiesis. The development and remodelling of bones require a delicate and accurate regulation of gene expression by epigenetic mechanisms that involve modifications of histone, DNA and RNA. The present review discusses the enzymes and proteins involved in mRNA m6A methylation modification and summarises current research progress and the mechanisms of mRNA m6A methylation in common orthopaedic diseases, including osteoporosis, arthritis and osteosarcoma. [ABSTRACT FROM AUTHOR]

The 1:1 structural order and B-site cation order in Pb(Mg1/3Nb2/3)O3 ceramics was significantly enhanced by Zr4+ substituting Nb5+ according to the chemical formula Pb(Mg1/3Zr2 x/3Nb2(1− x)/3)O3− x/3. The enhanced structural and cation order was revealed by both X-ray diffraction and transmission electron microscopy. The increased charge difference and the introduced oxygen vacancies were suggested to account for the observed long-range cation order. Typical relaxor ferroelectric behavior was retained even in the ceramics with a high degree of cation order. [ABSTRACT FROM AUTHOR]

Abstract: Estrogen induces endothelial progenitor cells (EPCs) migration and proliferation, which may serve as a potential target for coronary artery disease, but the mechanisms are unclear. We hypothesized that estrogen receptors (ERs) and phosphatidylinositol 3-kinase (PI3K) signaling pathway, which represent particularly important roles of action for estrogen, may contribute to estrogen-induced EPCs migration and proliferation. Bone marrow mononuclear cells (MNCs) were cultured in Dulbecco’s modified Eagle’s medium (DMEM) supplemented with growth factors as previously described. A total of 87.32±5.13% of adherent cells showed uptake of acetylated low-density lipoprotein and lectin binding. Immunostaining and fluorescence activated cell sorting confirmed the endothelial progenitor phenotype. RT-PCR, immunocytochemistry staining and Western blot demonstrated expression of ERs. Exposure to 17β-estradiol significantly improved EPCs migration and proliferation. Those effects were blocked by pretreatment with the pharmacological PI3K blockers LY294002 (1 h, 10 umol/L) and ICI-182780 (1 h, 10 umol/L), a specific estrogen receptor antagonist, which show involvement of estrogen receptors and PI3K pathway. These results suggest that estrogen induces EPCs migration and proliferation via ERs and PI3K pathway which provided a novel insight and treatment strategy of vascular biology. [Copyright &y& Elsevier]

In acid buffer solution, proteins with positive charge can react with anion surfactant and result in a great enhancement of synchronous light scattering (SLS) signals. In this contribution, the correlative experiment was made to compare the interaction of human serum albumin (HSA) and immunoglobulin G (IgG) with sodium dodecyl sulfonate (SDS). Based on the measurements of the polarization light scattering signals, a new method of scattering polarization was constituted to distinguish these two interaction systems with molecular weight difference (HSA 66 kDa; IgG 150 kDa). The results were consistent with the data measured by dynamic light scattering (DLS) technique. [ABSTRACT FROM AUTHOR]