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The vibration of a transformer core induced by magnetostriction is closely related to the environment and safety of devices. The DC bias excitation leads to the over saturation of the transformer core and causes more severe vibration. In this paper, a magnetic-mechanical strong coupling model based on a fixed-point time-periodic 2D finite element method with excitation voltage and DC bias current as the input is established in which the vector magnetic potential A, winding current I, and displacement in the core u are simultaneously taken as solution variables, and the fixed-point reluctivity is introduced to deal with the nonlinear problem of the core. In this model, the magnetic field and mechanical field are associated with the piezomagnetic equations and variational principle, and the circuit and magnetic fields are connected through the law of electromagnetic induction. The equivalent thickness of the core model and the determination of the initial value are discussed. A test transformer with a laminated core is made for experimental measurement. The accuracy and efficiency of the model proposed are verified by comparing the calculated results with the experimental results, and the influence of DC bias components on the magnetic characteristics and vibration of the transformer core is analyzed. [ABSTRACT FROM AUTHOR]

This paper is devoted to the statistical analysis on the recurrence intervals of rare events that are defined above a given threshold. The memory property of original records is found to have significant effects on the distribution and the correlation structure of recurrence intervals, so that some universal and non-universal properties arise. (i) For long-range persistent records by the ARFIMA processes, where large values are likely to follow large values, the recurrence intervals yield stretched exponential distributions and further show long-range persistence. (ii) For long-range anti-persistent records by the ARFIMA processes, the recurrence intervals obey exponential distributions, also absence of autocorrelation. (iii) For short-range autocorrelated records, the distribution and the correlation structure of recurrence intervals both depend on the parameters of the model and the threshold of rare events. [ABSTRACT FROM AUTHOR]

Anion binding properties of the isatin-based colorimetric HNI sensor (( Z )-3-(hydroxyimino)-5-nitroindolin-2-one) were investigated by UV–vis spectroscopy. Absorption response profiles of HNI varied dramatically for different anionic inputs by controlling the intramolecular charge transfer (ICT). These observations were utilized to construct logic functions of OR, NOR and the complementary INH/IMP sequential circuit. Further, reversible optical switches induced by alternative addition of F − and HSO 4 − were demonstrated with a ‘Write–Read–Erase–Read’ memory function possessing ‘multi-write’ ability. [ABSTRACT FROM AUTHOR]

A new method to optimally determine the fixed-point reluctivity is presented to ensure the stable and fast convergence of harmonic solutions. The diagonal fixed-point reluctivity matrix decouples the harmonic solutions and significantly reduces the memory requirement in computation. The nonlinear eddy current problem under dc-biased magnetization is computed by the fixed-point harmonic-balanced finite-element method. The computational performance of the new algorithm proves the validity and the efficiency of the proposed method. [ABSTRACT FROM AUTHOR]

This study identified a positive role of augmented reality (AR) hypnosis in the field of psychotherapy. The study utilised a 2 (gender: male vs. female) × 2 (hypnosis mode: AR hypnosis vs. ordinary hypnosis) between-groups experimental design. The psychological perception utility was significantly higher in females than in males, and the psychological perception utility of AR hypnosis was significantly higher than that of ordinary hypnosis. Differences existed between AR hypnosis and ordinary hypnosis for both males and females. The results show that AR hypnosis is effective in the psychotherapy of psychological stress and anxiety. This study serves as an important reference regarding psychotherapy based on AR. [ABSTRACT FROM AUTHOR]

A simple, highly selective and sensitive chemosensor (E)-2-((quinolin-8-ylimino) methyl) phenol ( QP ) has been developed for the fluoride, as demonstrated by the photophysical properties obtained by UV–vis and fluorescent methods. Excited-state inter/intramolecular proton transfer (ESPT) was suggested to be responsible for the fluoride-induced ‘turn on’ fluorescence and the blue shift of 25 nm in the emission spectrum. [ABSTRACT FROM AUTHOR]

The laminated core is tested under sinusoidal and dc-biased magnetizations. The measured data are manipulated by the proposed modified iterative method to obtain dc-biasing hysteresis loops accurately. The hysteresis model, based on a consuming function, is used to simulate the hysteresis effects of the iron core under different magnetizations. The fixed-point technique is combined with the harmonic-balanced method to compute exciting currents and magnetic fields simultaneously by considering the hysteresis effects. The global convergent strategies are presented to guarantee the convergence of harmonic solutions. The hysteretic characteristics and iron loss of the laminated core are analyzed on the basis of harmonic solutions of the magnetic field. [ABSTRACT FROM PUBLISHER]

The adsorption, dissociation and desorption of CO at different coverage over Rh(1 0 0) surface have been systematically investigated using density functional theory method together with the periodic slab model. Our results show that at the coverage less than or equal to 4/12 ML, CO favored the most stable bridge site adsorption, and the adsorption energies of CO have little difference; while at the coverage greater than or equal to 5/12 ML, the lateral repulsive interaction begins to affect the adsorption structures and the corresponding adsorption energies of adsorbed CO molecules, and the interaction will be stronger with the increasing of CO coverage, which leads to CO migration over Rh(1 0 0) surface when CO coverage is greater than or equal to 10/12 ML. The adsorption energies of these CO molecules will decrease successively until the saturated adsorption with the CO coverage of 12/12 ML. Further calculations on CO dissociation indicate that when CO coverage is greater than or equal to 3/12 ML, the dissociation of adsorbed CO molecules will be unfavorable both kinetically and thermodynamically, suggesting that only molecule CO adsorption are favored. Considering the catalytic activity of Rh(1 0 0) surface toward CO dissociation and the higher CO coverage under the continuous supply of CO in syngas conversion, it is to be expected that only molecule CO adsorption exist on Rh catalyst. [ABSTRACT FROM AUTHOR]

In this paper, we study the nonexistence result of the following nonlinear elliptic equation with Robin boundary condition { − Δ u = | u | p − 1 u in R + N , ∂ u ∂ ν + c u = 0 on ∂ R + N . Under some assumptions on c and p , we will show that this problem does not possess nontrivial bounded solution with finite Morse index. [ABSTRACT FROM AUTHOR]

To explore the effective components, potential targets and neuroprotective related mechanisms of Mijianchangpu decoction (MJCPD), a well-known TCM used by the Chinese Hui minorities to treat stroke, on the prevention and treatment of ischemic stroke (IS) by using experimental models combined with network pharmacology. The neuroprotective efficacy of MJCPD was estimated by applying the middle cerebral artery occlusion (MCAO) induced cerebral ischemia rats, and the neurological deficits score, TTC and HE staining as well as behavioral evaluation tests were employed to evaluate the beneficial effects. Meanwhile, the bioactive components of MJCPD responsible for the neuroprotective effects were identified by detecting the constituents in the brain of the MCAO rats with UHPLC-QTOF-MS/MS techniques, and these compounds were then underwent for network pharmacology analysis. Firstly, the targets of the bioactive compounds of MJCPD were predicted using Pharmmapper database, and simultaneously, the targets of IS disease were obtained from disease databases including DisGenet, OMIM, and GeneCards. Secondly, the protein-protein interaction (PPI) network between the targets and diseases were established to give the possible therapeutic targets for IS. Thirdly, the go function and KEGG pathway enrichment analysis were carried out and the compound-target-pathway network was constructed by Cytoscape software. Finally, the effective compounds, core targets and possible pathways were obtained by analyzing the connectivity of the network. More importantly, the core targets were verified by western blot experiments to validate the reliability of this study. MJCPD exhibited significant neuroprotective effect on IS, and 16 bioactive components of MJCPD were identified in the brain of the MCAO rats. 59 and 1982 targets related with IS disease were explored from Pharmapper and disease databases, respectively, and 32 intersecting targets were obtained as hypothetical therapeutic targets. Based on the results of the compound-target-pathway and PPI network with the degree was greater than the median, 8 effective compounds (suberic acid, epishyobunone, crocetin monomethyl ester, sfaranal, (Z)-6-octadccenoic acid, nerolidol and gurjunene) and 5 hub targets (SRC, MAPK8, MAPK14, EGFR and MAPK1) as well as 12 pathways were predicted. Western blot results showed that EGFR, p38, ERK and SRC proteins were expressed significantly different after MJCPD treatment as compared with the model group. The present study employed network pharmacology, pharmacodynamics and molecular biology techniques to predict and validate the core potential targets and signaling pathways as well as the bioactive components of MJCPD responsible for the treatment of IS. All of which are very helpful to clarify the neuroprotective mechanism of MJCPD, and obviously, the active compounds and targets in this study can also provide clues for the treatment of IS. [Display omitted] [ABSTRACT FROM AUTHOR]

Exploring highly efficient, cost-effective, and stable electrocatalysts toward oxygen evaluation reaction (OER) is of great significance for hydrogen generation. Herein, in situ growth of NiFe-borate layered double hydroxide (NiFe-BLDH) nanosheets on waste biomass-derived nitrogen-doped carbon (NC) with hierarchical architecture under microwave hydrothermal conditions is reported. The as-synthesized NiFe-borate layered double hydroxide/nitrogen-doped carbon (NiFe-BLDH/NC) exhibits outstanding OER activity, showing an extremely low overpotential of 243 mV at the current density of 10 mA cm−2 and a relatively small Tafel slope of 42.7 mV dec−1, which are superior to the commercial RuO 2 and many previously reported NiFe-LDH-based OER electrocatalysts. Additionally, the catalyst also shows remarkable stability with unobvious decrease of current density over a period of 24 h. These excellent catalytic performances could be attributable to the synergistic effects between the conductive NC scaffold and NiFe-BLDH with excellent hydrophilicity caused by the intercalated borate anions, which provide many advantages, such as large surface area, abundant active sites, fast charge and mass transport pathways. This work provides new insights into the design and facile preparation green and efficient electrocatalysts Ultrathin NiFe-borate layered double hydroxide (NiFe-BLDH) nanosheets are vertically grown on waste biomass derived nitrogen doped carbon (NC) with multistage decentralized architecture to obtain NiFe-BLDH/NC electrocatalyst for OER. Benefiting from the strong synergetic effect of borate anion intercalated NiFe-LDH and conductive NC for abundant catalytic sites, superior electronic conductivity, quick oxygen diffusion and release, the as-synthesized NiFe-BLDH/NC exhibits outstanding OER activity, even superior to commercial RuO 2 and many previously reported NiFe-LDH system. This work not only demonstrates that NiFe-BLDH/NC is a high-efficiency, stable, and cost-effective electrocatalysts, but also provides a strategy for rational design of low cost, highly active, and practical electrocatalysts towards energy-related applications. [Display omitted] • NiFe-BLDH/NC nanocomposite with multistage decentralized architecture has been prepared. • The conversion of waste biomass into NC complies with the concept of green and sustainable. • The as-synthesized NiFe-BLDH/NC nanocomposite exhibits outstanding OER activity. • The superior OER performance may ascribed to the strong synergetic effect of NiFe-BLDH and NC. • The existing of borate anion in electrocatalyst also play an important role in improving OER performance. [ABSTRACT FROM AUTHOR]

ZnO is a wide band gap semiconductor metal oxide that not only has excellent electrical properties but also shows excellent gas-sensitive properties and is a promising material for the development of NO2 sensors. However, the current ZnO-based gas sensors usually operate at high temperatures, which greatly increases the energy consumption of the sensors and is not conducive to practical applications. Therefore, there is a need to improve the gas sensitivity and practicality of ZnO-based gas sensors. In this study, three-dimensional sheet-flower ZnO was successfully synthesized at 60 °C by a simple water bath method and modulated by different malic acid concentrations. The phase formation, surface morphology, and elemental composition of the prepared samples were studied by various characterization techniques. The gas sensor based on sheet-flower ZnO has a high response value to NO2 without any modification. The optimal operating temperature is 125 °C, and the response value to 1 ppm NO2 is 125. At the same time, the sensor also has a lower detection limit (100 ppb), good selectivity, and good stability, showing excellent sensing performance. In the future, water bath-based methods are expected to prepare other metal oxide materials with unique structures. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, the long-range cross-correlation of Chinese stock indices is systematically studied. The multifractal detrended cross-correlation analysis (MF-DXA) appears to be one of the most effective methods in detecting long-range cross-correlation of two non-stationary variables. The Legendre spectrum and the large deviations spectrum are extended to the cross-correlation case, so as to present multifractal structure of stock return and volatility series. It is characterized of the multifractality in Chinese stock markets, partly due to clusters of local detrended covariance with large and small magnitudes. [Copyright &y& Elsevier]

[Display omitted] • Two novel high-capacity and high-stability anode materials for MXenes lithium-ion batteries. • A functional relationship that makes it easy to explore more MXenes materials. As an advanced battery technology, lithium-ion batteries have attracted extensive attention, especially in electric vehicles. However, low capacity and poor stability are two factors hindering more extensive application of lithium-ion batteries. Herein, we performed a screening study on MXenes including M 2 C, MC 2 , M 2 N, MN 2 (M = Sc, Ti, V, Cr), in the search for promising lithium-ion battery anode materials by using density functional theory (DFT) calculations and ab initio molecular dynamic (AIMD) simulations. The theoretical capacities of Ti 2 N and V 2 N are 975 mAh/g and 924 mAh/g, respectively. Based on low deformation rate, and small energy variation, Ti 2 N and V 2 N have higher stability than that of graphite electrodes. The lower diffusion barrier accelerates the charging and discharging process of the battery. Considering their low diffusion barrier, excellent conductivity, high theoretical capacity, low deformation rate and high thermal stability, Ti 2 N and V 2 N are proposed as promising anode materials for lithium-ion batteries. The adsorption of lithium-ion belongs in the category of weak adsorption where the d -band center is negative. However, it is strong adsorption when the d -band center is positive. A linear relationship between the lithium-ion concentration and adsorption energy is developed for strong adsorption, which can be used to guide the design of high-capacity electrode materials. [ABSTRACT FROM AUTHOR]

NaOH/urea aqueous solution is a novel, green solvent for cellulose. To explain why cellulose just be dissolved in this solvent under −13 °C, we studied and discussed the dissolving process of cellobiose in water, urea solution, NaOH solution and NaOH/urea aqueous solution. Dissolving cellobiose in water and the urea solution absorb heat, which is an entropy-driven process. Dissolving cellobiose in NaOH solution and mixed NaOH/urea solution is exothermic, which is an enthalpy-driven process. OH plays an important role in the dissolving process by forming a hydrogen-bonding complex. From the thermodynamic point of view, negative entropy can well interpret why cellulose must be dissolved in cold NaOH/urea aqueous solution. [ABSTRACT FROM AUTHOR]

The magnetic flux includes dc component and ac component in the square laminated core (SLC) under dc-biased magnetization. Hysteresis loops are distorted by dc component of magnetic field intensity in ferromagnetic core and exhibit asymmetrical and special nonlinearities. A neural network (NN) is trained on the basis of the experimental data to model hysteresis effects in the limb-yoke of the SLC. Hysteresis effects in the mitered-joint region are modeled by the consuming function combined with the dc-biasing magnetization curve. The global fixed-point magnetic reluctivity is properly determined in harmonic-balanced finite-element method (HBFEM) to ensure globally convergent computation. The magnetic field in the SLC under dc-biased magnetization is computed by the proposed method taking account of the dc-biasing hysteresis effects. [ABSTRACT FROM PUBLISHER]

The ferromagnetic core of power transformer is susceptible to dc bias and has special nonlinear and hysteretic characteristics under dc-biased magnetization. The dc-biasing magnetization curve of a square laminated core (SLC) can be obtained by dc bias test. The harmonic-balanced finite-element method (HBFEM) combined with the fixed-point technique is used to calculate the dc-biasing magnetic field in the SLC based on the measured dc-biasing magnetization curve. A locally convergent method in harmonic domain is presented to determine the fixed-point reluctivity, which can speed up the convergence of harmonic solution. The dc-biasing magnetic fields are computed by using the basic and dc-biasing magnetization curves respectively. The results indicate the dc-biasing magnetization curve is more reasonable than the basic one in the analysis. [ABSTRACT FROM PUBLISHER]

In this paper, a model for an ethylene slurry polymerization system using supercritical propane as a solvent is developed by adopting a set of thermodynamic and kinetic parameters using fundamental chemical engineering principles and Polymers Plus software. The Ziegler–Natta catalyst is characterized by assuming the existence of multiple types of catalyst sites and deconvolution data from gel permeation chromatography to determine the most probable chain-length distribution and relative amounts of polymer produced at each site type. A set of suitable reaction subclasses and kinetic constants for different site types that fit plant conditions is developed, validating our model. The values calculated for production rate, ethylene conversion, residence time, H2/C2H4molar ratio in the reactor, number-average molecular weight, and polydispersity index are all close to actual values, verifying that our model accurately describes plant conditions. [ABSTRACT FROM AUTHOR]

Abstract: Multifractal detrended cross-correlation analysis (MF-DXA) has been developed to detect the long-range power-law cross-correlation of considered signals in the presence of non-stationarity. However, crossovers arising from extrinsic periodic trends make the scaling behavior difficult to analyze. We introduce a Fourier filtering method to eliminate the trend effects and systematically investigate the multifractal cross-correlation of simulated and real traffic signals. The crossover locations are found approximately corresponding to the periods of underlying trend. Traffic velocity on one road and flows on adjacent roads show strong cross-correlation. They also present weak multifractality after periodic trends are removed. The traffic velocity and flow are cross-correlated in opposite directions which is accordant to their actual evolution. [Copyright &y& Elsevier]

Multifractal detrended cross-correlation analysis (MF-DXA) has been developed to detect the long-range power-law cross-correlation of two simultaneous series. However, the synchronization of underlying data can not be guaranteed integrated by a variety of factors. We artificially imbed a time delay in considered series and study its influence on the multifractal cross-correlation analysis. Time delay is found to affect the multifractal characterization, where a larger time delay causes a weaker multifractality. We also propose an alternative modification on MF-DXA to make the process more robust. The logarithmic return and volatility of Chinese stock indices show cross-correlation scaling behavior and strong multifractality by MF-DXA as well as singularity spectrum analysis. [ABSTRACT FROM AUTHOR]

Branched self-assembling peptides bearing epitopes with free N-termini were designed. A lysine residue was used as branch point to present more than one epitopes in a single peptide. Atomic force microscope, circular dichroism and Fourier transform infrared spectroscopy data indicate that the N-terminus attached epitope sequences do not prevent the formation of the β-sheets and the self-assembling of these peptides into stable nanofibers in aqueous solutions. Rheology experiments show that these peptides could form self-supporting scaffolds once electrostatic repulsions were screened by electrolytes. Fluorescence spectra measurements upon binding of FITC-avidin to surfaces of nanofibers were performed to investigate the effect of charged aspartic acid residues in RGD epitopes at the lysine branching on packing and accessibility of the epitopes. Results show that the electrostatic interaction between hydrophilic side chains at branching and nanofiber surfaces may significantly affect the conformational freedom and accessibility of the epitopes at the periphery of the nanofibers. Cell entrapment experiments reveal that the attached RGD epitopes with free N-termini are biological active. [ABSTRACT FROM AUTHOR]

An Epstein frame-like core model is set up to study the dc-biased problem of the power transformer. The harmonic phenomenon of the model under the dc bias condition is investigated by using the harmonic-balance finite-element method (HBFEM). The harmonic-balance finite element equation is coupled with the external electric circuit. Each harmonic component of the magnetizing current and magnetic field can be calculated directly in the harmonic frequency domains. Comparing the calculated results with the experimental data shows consistency. The dc bias effects on the magnetizing current and the magnetic induction are analyzed through the harmonic solutions. [ABSTRACT FROM AUTHOR]

Abstract: A surfactant is briefly defined as a material that can greatly reduce the surface tension of water when used in very low concentrations. Surfactants are usually organic compounds that are amphiphilic, containing both hydrophobic groups and hydrophilic groups. Therefore, they are soluble in both organic solvents and water. Many surfactants can also assemble in the bulk solution into aggregates such as vesicles and micelles. Self-assembling peptides are a novel category of designer peptides that can undergo spontaneous organization into well-ordered nanostructures with the great potentials in nanotechnology, nanomedicine including 3-dimensional (3-D) cell culture, drug delivery, wound repair, and so on. In this review, we introduce a family of designer surfactant-like peptides: the self-assembling peptides which have been derived by mimicking the structure of traditional surfactants. [Copyright &y& Elsevier]

Abstract: Chemotaxis, cell migration directed by spatial concentration gradients of chemoattractant molecules, is critical for proper function of the immune system. Materials capable of generating defined chemoattractant gradients via controlled release may be useful for the design of improved vaccines and immunotherapies that draw specific cells to an immunization site. To this end, we encapsulated formyl-Nle-Leu-Phe-Nle-Tyr-Lys (fN’LFN’YK) peptides or macrophage inflammatory protein-3α (MIP-3α or CCL20) in degradable poly(lactide-co-glycolide) microspheres that provided sustained release for more than 2 weeks in vitro. fN’LFN’YK and MIP-3α chemoattract dendritic cells (DCs), the key antigen-presenting cells involved in generation of primary immune responses, and their precursors, monocytes. Using an in vitro videomicroscopy migration assay, we detected strong chemotaxis of human monocytes and monocyte-derived DCs through 3D collagen gels toward microspheres releasing fN’LFN’YK. Similarly, microparticles releasing MIP-3α were able to attract mouse bone marrow-derived dendritic cells. Strikingly, prolonged attraction of DCs from distances up to 500μm from the source to the point of contact with individual microspheres was observed. Such microspheres could be of general interest for the design of vaccines that promote adaptive immunity and as a platform for studying the biology of chemotaxis in vitro and in vivo. [Copyright &y& Elsevier]

We used a class of designed peptide detergents to stabilize photosystem I (PS-I) upon extended drying under N2 on a gold-coated-Ni-NTA glass surface. PS-I is a chlorophyll-containing membrane protein complex that is the primary reducer of ferredoxin and the electron acceptor of plastocyanin. We isolated the complex from the thylakoids of spinach chloroplasts using a chemical detergent. The chlorophyll molecules associated with the PS-I complex provide an intrinsic steady-state emission spectrum between 650 and 800 nm at −196.15 °C that reflects the organization of the pigment-protein interactions. In the absence of detergents, a large blue shift of the fluorescence maxima from approximately 735 nm to approximately 685 nm indicates a disruption in light-harvesting subunit organization, thus revealing chlorophyll−protein interactions. The commonly used membrane protein-stabilizing detergents, N-dodecyl-β-D-maltoside and N-octyl-β-D-glucoside, only partially stabilized the approximately 735-nm complex with approximately 685-nm spectroscopic shift. However, prior to drying, addition of the peptide detergent acetyl- AAAAAAK at increasing concentration significantly stabilized the PS-I complex. Moreover, in the presence of acetyl- AAAAAAK, the PS-I complex is stable in a dried form at room temperature for at least 3 wk. Another peptide detergent, acetyl-VVVVVVD, also stabilized the complex but to a lesser extent. These observations suggest that the peptide detergents may effectively stabilize membrane proteins in the solid-state. These designed peptide detergents may facilitate the study of diverse types of membrane proteins. A designer peptide detergent may facilitate the study of diverse types of membrane proteins. [ABSTRACT FROM AUTHOR]

Most human malignancies are caused by somatic alterations within the cancer genome, leading to oncogene activation or tumor suppressor gene inactivation. The sequence of the human genome has enabled systematic approaches to identify cancer genome alterations, including point mutations, copy number increases and decreases, loss of allelic heterozygosity, and chromosome translocations. Systematic cancer genome analysis has recently led to the discovery of somatic mutations in the BRAF, PIK3CA, and EGFR genes, among others. With further development of targeted cancer therapies and improvement in genome analysis technology, genome-wide surveys of cancer will likely become tools for diagnosis as well as discovery. [Copyright &y& Elsevier]

The rapid and sensitive determination of pathogenic bacteria is extremely important in biotechnology, medical diagnosis, and the current fight against bioterrorism. Current methods either lack ultra sensitivity or take a long time for analysis. Here, we report a bio conjugated nanoparticle-based bioassay for in situ pathogen quantification down to single bacterium within 20 min. The bios conjugated nanoparticle provides an extremely high fluorescent signal for bioanalysis and can be easily incorporated with biorecognition molecules, such nobody. The antibody-conjugated nanoparticles can readily and specifically identify variety of bacterium, such as Escherkhia coil 0157 H7, through antibody-antigen inter. The single-bacterium-detection capability within 20 min has been confirmed by the plate-counting method and realized by using two independent optical techniques. The two detection methods correlated extremely well. Furthermore, we were able to detect multiple bacterial samples with high through- put by using a 384-well microplate format. ,o show the usefulness of this assay, we have accurately detected 1-400 E coIl 0157 bacterial cells in spiked ground beef samples. Our results demons strate the potential for a broad application of bioconjugated nanoparticles in practical biotechnological and medical applications in various biodetection systems. The ultimate power of integrating bionano technology into complex biological systems will emerge as a revolutionary tool for ultra sensitive detection of disease markers and infectious agents. [ABSTRACT FROM AUTHOR]

Biotechnology has generally been associated with gene cloning and expression, genomics, high throughput drug discovery, biomedical advancement and agricultural development. That is about to change. Biotechnology will expand to encompass discovery and fabrication of biological and molecular materials with diverse structures, functionalities and utilities. The advent of nanobiotechnology and nanotechnology have accelerated this trend. Analogous to the construction of an intricate architectural structure, diverse and numerous structural motifs are used to assemble a sophisticated complex. Nature has selected, produced and evolved numerous molecular architectural motifs over billions of years for particular functions. These molecular motifs can now be used to build materials from the bottom up. Biotechnology will continue to harness nature''s enormous power to benefit other disciplines and society as a whole. [Copyright &y& Elsevier]

Inorganic nanostructures that interface with biological systems have recently attracted widespread interest in biology and medicine. Nanoparticles are thought to have potential as novel luminescent probes for both diagnostic (e.g., imaging) and therapeutic (e.g., drug delivery) purposes because of their size comparable to biomolecules and their novel optical, electronic, and magnetic properties. Critical issues for successful nanoparticle delivery include the ability to target specific tissues and cell types and escape from the biological particulate filter known as reticuloendothelial system. Three distinct types of luminescent nanoparticles have been identified which show promise in bioanalysis, namely dye-doped nanoparticles, semiconductor and metal nanoparticles. In this article we examine the recent advances in the development of dye-doped nanoparticles, metal and semiconductor nanoparticles, bioconjugation schemes to attach these nanoparticles to biomolecules and a few biological applications. [ABSTRACT FROM AUTHOR]

A sensitive fluorescent sensing membrane has been developed for the rapid detection of sodium ions by immobilizing the membrane onto a glass slide surface. The membrane consists of a fluorophore, an ionophore, a plasticizer, and an anionic site of a lipophilic salt in a polyvinyl chloride (PVC) matrix. Based on the ion-exchange response and photoinduced electron transfer mechanisms, the ionophore first captures target sodium ions from the solution into the membrane, and then the fluorophore emits a fluorescent signal based on the amount of sodium ions captured. To effectively transmit the signal and avoid the leaching of the fluorophore from the membrane, a newly synthesized fluorescent compound was used as a fluorophore in the fabrication of the membrane. Due to the special structure of the fluorophore, it remains trapped inside the membrane and thus gives a reliable fluorescent signal when sodium ions exist in the solution. Calix[4]arene tetraester acts as a sodium ion carrier, the crown size in its molecular structure is compatible with the sodium ionic size, making the membrane highly selective to sodium ions. Furthermore, the membrane demonstrates a rapid response to sodium ions—less than 1 min is required to reach a stable fluorescent signal. The sodium content in various real samples, such as mineral water, urine, and serum, were determined by the sensing membrane. The results highly correlate with the atomic absorption spectrometry method, confirming the validity of the fluorescent sensing membrane for sodium ion detection. [ABSTRACT FROM AUTHOR]

Mutations in tcl-2 cause defects in the specification of the fates of the descendants of the TL and TR blast cells, whose polarity is regulated by lin-44/Wnt and lin-17/frizzled, during Caenorhabditis elegans development. In wild-type animals, POP-1/TCF/LEF, is asymmetrically distributed to the T cell daughters, resulting in a higher level of POP-1 in the nucleus of the anterior daughter. The POP-1 asymmetric distribution is controlled by lin-44 and lin-17. However, in tcl-2 mutants, POP-1 is equally distributed to T cell daughters as is observed in lin-17 mutants, indicating that, like lin-17, tcl-2 functions upstream of pop-1. In addition, tcl-2 mutations cause defects in the development of the gonad and the specification of fate of the posterior daughter of the P12 cell, both of which are controlled by the Wnt pathway. Double mutant analyses indicate that tcl-2 can act synergistically with the Wnt pathway to control gonad development as well as P12 descendant cell fate specification. tcl-2 encodes a novel protein. A functional tcl-2::gfp construct was weakly expressed in the nuclei of the T cell and its descendants. Our results suggest that tcl-2 functions with Wnt pathways to control T cell fate specification, gonad development, and P12 cell fate specification. [Copyright &y& Elsevier]

This paper describes the development of oligonucleotide-functionalized nanoparticles. We used disulfide-coupling chemistry for the immobilization of oligonucleotides onto silica nanoparticles and subsequently demonstrated the properties of the resulting DNA nanoparticles. Factors influencing the immobilization and hybridization processes were examined and optimized. The oligonucleotide-modified silica nanoparticles provide an efficient substrate for hybridization and can be used in the development of DNA biosensors and biochips. [Copyright &y& Elsevier]

Three-dimensionally ordered hollow borate anions intercalated CoMgAl-LDH ball-flower with hierarchical porous structure have been prepared by using zeolitic imidazolate framework-67 (ZIF-67) as a self-sacrificing template. After calcination it, the obtained CoMgAl-borate LDO can inherit the hollow hierarchical porous structure. Its unique structure has the merits of low density, large specific surface area, large pore size distribution and short diffusion pathway, which should be beneficial to the adsorption of larger dye molecules. The maximum uptake capacity of CoMgAl-borate LDO can even reach as high as 1493.3 mg g−1 for Congo red (CR) and 990.1 mg g−1 for methyl orange (MO) owing to the hierarchical hollow porous structure, the "memory effect", electrostatic interactions, hydrogen bond and ion exchange between anionic dye and cationic adsorbent surface, surpassing those of most previously reported LDH-based adsorbents. The entire adsorption processes for CR and MO follow Langmuir isotherm and pseudo-second-order kinetics model. Moreover, the removal efficiency of CoMgAl-borate LDO can still reach 86.5% for CR and 84.3% for MO after recycling five times, indicating that CoMgAl-borate LDO is a very promising high-efficiency adsorbent. This work not only demonstrates that CoMgAl-borate LDO is a very green and efficient adsorbent for the removal of anionic dyes from wastewater, but also provides a strategy for the rational design and development of hollow nanostructures. [Display omitted] • Hollow CoMgAl-borate LDH ball-flowers with hierarchical porous structure have been prepared. • The morphology well retained CoMgAl-BLDO were obtained by calcination of CoMgAl-BLDH. • CoMgAl-BLDO exhibit excellent adsorption performances for CR or MO pollutant. • It can be as a very promising high-efficiency adsorbent for wastewater remediation. • This study shed light on the rational design and fabrication of hierarchical hollow porous adsorbent. [ABSTRACT FROM AUTHOR]

Different from the extant power flow analysis methods, this paper discusses the power flows for the unified power quality conditioner (UPQC) in three-phase four-wire systems from the point of view of impedance matching. To this end, combined with the designed control strategies, the establishing method of the UPQC impedance model is presented, and on this basis, the UPQC system can be equivalent to an adjustable impedance model. After that, a concept of impedance matching is introduced into this impedance model to study the operation principle for the UPQC system, i.e., how the system changes its operation states and power flow under the grid voltage variations through discussing the matching relationships among node impedances. In this way, the nodes of the series and parallel converter are matched into two sets of impedances in opposite directions, which mean that one converter operates in rectifier state to draw the energy and the other one operates in inverter state to transmit the energy. Consequently, no matter what grid voltages change, the system node impedances are dynamically matched to ensure that output equivalent impedances are always equal to load impedances, so as to realize impedance and power balances of the UPQC system. Finally, the correctness of the impedance matching-based power flow analysis is validated by the experimental results. [ABSTRACT FROM AUTHOR]

The microstructure and nanoindentation creep behavior of characteristic phases in TiC reinforced steel matrix composite after stabilizing heat treatments were investigated. The results showed that the microhardness of matrix increased from 4.85 ± 0.30 GPa in the annealed sample to 13.45 ± 0.71∼ 16.06 ± 0.88 GPa after stabilizing heat treatments, and the apparent hardness of TiC particle was also improved due to the martensitic strengthening of matrix. The dominant creep mechanism of the composite was dislocation movement, the primary micro creep stage dominated the micro creep behavior of annealed composite and the steady state creep dominated the micro creep behavior of stabilized composites. The micromechanical properties of the characteristic phases in the composite after TCC treatment were well matched, and the overall creep resistance of that was excellent, which provided theoretical support in achieving the consistency of micromechanical properties of the composite during the stabilizing heat treatments. [Display omitted] [ABSTRACT FROM AUTHOR]

Civil aviation freight transport (CAFT) in China plays an important role in social and economic development. However, research on the morphological structure of China's CAFT network and its influence factors remains rare. In this paper, we focus on this topic by using a new data set of China's domestic routes from 2015 to 2019. With the complex network theory, we make an empirical study on the morphological structure of China's domestic CAFT network, and try to explore the nexus between the attributes of the network and the influence factors. The results show that China's domestic CAFT network is in line with the small world network model, which has a low average path length and a high clustering coefficient. The centrality of the network presents a saddle distribution with dense in the east and west, while sparse in the central. The results also indicate that there are many localized networks dominated by a few core airports. A number of regional hub cities exist, which are mainly located in the west of China. The development of China's CAFT highly depends on the civil aviation passenger transport (CAPT) network, and is highly affected by GDP, the industrial structure and the geographical location of cities. Finally, we give several policy suggestions, including developing the freight dedicated airports, establishing independent freight transport network system, vigorously developing core and intermediate hub cities, as well as constructing the regional network. • We study China's domestic civil aviation freight transport network by using a new dataset. • We analyze the network attributes and their influence factors at the city level. • A number of regional hub cities exist, mainly located in the west of China. • Civil aviation passenger transport, GDP and geographical location are the critical influencing factors of the network. [ABSTRACT FROM AUTHOR]

Sealing performance between two contacting surfaces is of significant importance to stable operation of proton exchange membrane (PEM) fuel cells. In this work, an analytical micro-scale approach is first established to predict the gas leakage in fuel cells. Gas pressure and uneven pressure distribution at the interface are also included in the model. At first, the micro tortuous leakage path at the interface is constructed by introducing contact modelling and fractal porous structure theory. In order to obtain the leakage at the entire surface, contact pressure distribution is predicted based on bonded elastic layer model. The gas leakage through the discontinuous interface can be obtained with consideration of convection and diffusion. Then, experiments are conducted to validate the numerical model, and good agreement is obtained between them. Finally, influences of surface topology, gasket compression and gasket width on leakage are studied based on the model. The results show that gas leakage would be greatly amplified when the asperity standard deviation of surface roughness exceeds 1.0 μm. Gaskets with larger width and smaller thickness are beneficial to sealing performance. The model is helpful to understand the gas leakage behavior at the interface and guide the gasket design of fuel cells. [Display omitted] • An analytical model is built to predict gas leakage rate in fuel cells. • Uneven pressure distribution at the interface is considered in the model. • Leakage is amplified when asperity height standard deviation exceeds 1.0 μm. • Leakage becomes serious when gasket compression ratio is lower than 8%. • Gaskets with larger width and smaller thickness are beneficial to sealing. [ABSTRACT FROM AUTHOR]

The metal oxides with low trap density of states as the electron transport layer are crucial for the high performance of the organic solar cells (OSCs). It is universally acknowledged that modifying n-type metal oxide contacts with polymer donors will harm the carrier extraction on account of the mismatched energy level. However, we find that modifying interlayer consisting of the alcohol amines with some polymer donor additive can unusually enhance the performance of the OSCs. Compared with triethanolamine (TEA) passivated ZnO, TEA:polymer donor treated ZnO shows lower trap density and enhances electron mobility resulting in higher current density in OSC devices. Here, we reveal that the enhanced oxygen-defect passivation ability of TEA with polymer additive is attributed to the enhanced negative electrostatic potential of TEA owing to the hydrogen bond formation between the polymer and the hydroxyl group in TEA. This strategy that enhancing the negative electrostatic potential of the passivators for improving oxygen defect passivation can be extended to other types of organic electronic devices. [ABSTRACT FROM AUTHOR]

• The pepper endophyte Bacillus velezensis LY7 has antifungal activity. • Strain LY7 contains a rare cupin domain-containing protein OS with antifungal activity. • Cupin domain-containing protein OS induces the expression of genes in anthracnose. • LY7 increased JA and SA levels to improve the stress resistance of pepper plants. • LY7 treatment to seedlings has potential for pepper biocontrol and growth promotion. Anthracnose of pepper (Capsicum annuum L), caused by Colletotrichum scovillei , is one of the three major diseases of pepper that seriously impact yield and quality. As an alternative to the use of synthetic chemical pesticides, a variety of endophytic bacteria have been reported to be potential biocontrol agents with the ability to improve disease resistance and abiotic stress tolerance in host plants. However, the mechanisms of action by which these different bacterial biocontrol agents inhibit the onset and development of disease, in some cases, remains unclear. In the present study, the potential use of the endophytic bacterial strain Bacillus velezensis LY7, originally isolated from pepper leaves, as a biocontrol agent was evaluated. More specifically, the ability of LY7 to control anthracnose in pepper and promote growth was assessed in pot experiments in a greenhouse and in vitro assays. Results indicated that the use of B. velezensis LY7 enhanced the synthesis of jasmonic acid and other hormones in pepper plants, as well as increased disease resistance and plant growth. A 200 × dilution of LY7 fermentation broth reduced disease incidence up to 90.70 %, while also enhancing plant growth. The mechanism of action of LY7 was also evaluated. Results indicated that LY7 secreted an antibiotic protein possessing a cupin domain OS. RNA-sequence analysis of the transcriptome of C. scovillei at several timepoints after exposure to LY7 (24, 48, and 72 h) revealed the up- and down-regulation of several genes. More specifically, LY7 induced the expression of genes associated with biosynthesis pathways and transcription factors involved in anthracnose pathogenicity. Our results indicate that the LY7 strain of induces hormone synthesis in pepper plants that results in enhanced disease resistance and promotes growth, as well as enhances stress tolerance by enhancing antioxidant and defense-related enzyme activity. These results demonstrate the potential of using LY7 for the biocontrol of anthracnose in pepper plants. [ABSTRACT FROM AUTHOR]

In order to solve the challenge of poor protection of conventional NbSi 2 coatings in high temperature oxidation environments, a new TiB 2 -modified (Nb,Mo,Cr)Si 2 composite ceramic coating was prepared on the surface of Nb521 substrate by triple slurry sintering method. The composite ceramic coating maintained the complete morphology after oxidation at 1600 ℃ for 15 h, due to the oxide layer TiO 2 -(Ti 0.6 Cr 0.2 Nb 0.2)O 2 -SiO 2 formed on the coating surface, which could effectively reduce the volatilization behavior of SiO 2 and prolongue the oxidation life of the coating by wrapping the SiO 2 layer. In addition, the coating successfully withstood 1500 cycles from room temperature to 1600 ℃, due to the fact that CrSi 2 and MoSi 2 significantly modulated the difference in thermal expansion coefficients between the Nb521 substrate and the NbSi 2 coating, making the thermal stress generated during the thermal shock cycle lower than the intrinsic strength of the coating. [ABSTRACT FROM AUTHOR]

Novel magnetic microspheres with core-shell structure, Fe 3 O 4 @SiO 2 @MgAl-borate LDH had been fabricated by a facile hydrothermal approach, in which the borate anions intercalated layered double hydroxides (MgAl-borate LDHs) loaded on a SiO 2 -coated Fe 3 O 4 magnetite core, forming a flower-like hierarchical porous structure constructed by the assembly of ultrathin nanosheets. This composite was characterized via XRD, SEM, TEM, FT-IR, XPS, TG-DSC and VSM. It possessed superparamagnetic property, large specific surface area, moderate pore volume and excellent chemical stability. Benefiting from this unique structure, it exhibited superb adsorption performance. Its maximum adsorption capacities were 158.98 mg g−1 for CR at 298 K with pH = 4 and 86.73 mg g−1 for Cr(VI) at 298 K with pH = 5, which were larger than most of other similar adsorbent. The adsorption reaction followed the Langmuir model as well as pseudo-second-order rate equation. The higher temperature was in favour of adsorption. The ionic strength showed little effect on the sorption Cr(VI). Furthermore, the possible formation mechanism of this composite and its adsorption mechanism were also proposed. Overall, this new composite is expected to be an excellent adsorbent for CR and Cr (VI) in wastewater due to its superior structural stability, high efficiency, good reusability, and easy collection by magnetic separation. Novel magnetic microspheres with core-shell structure, Fe 3 O 4 @SiO 2 @MgAl-borate LDH, have been fabricated. Outer MgAl-borate LDH displays flower-like hierarchical porous structure constructed by the assembly of ultrathin nanosheets.It exhibited excellent adsorption performances for CR and Cr(VI) pollutants respectively. It can be easily separated from solution in the presence of an external magnetic field. This new composite could be as promising candidates for removal of CR and Cr(VI) pollutants. Image 1 • Fe 3 O 4 @SiO 2 @MgAl-borate LDH magnetic microspheres with core-shell structure have been fabricated. • Flower-like hierarchical porous structure was constructed by the assembly of ultrathin nanosheets. • It exhibits excellent adsorption performances for CR and Cr(VI) pollutants respectively. • It can be easily separated from solution in the presence of an external magnetic field. • This composite could be as a promising candidate for removal of CR and Cr(VI) pollutants. [ABSTRACT FROM AUTHOR]

• The hollow Se-(CoFe)S 2 boxes was fabricated by sulfurization of Co-Fe PBAs precursor and subsequent Se doping strategy for electrocatalytic OER and supercapacitor. • The robust hollow framework with heterointerface/defects of Se-(CoFe)S 2 has large specific surface, more active sites and good surface permeability to provide great advantages for fabricating electrode materials. • The doping of different non-metal-anion into the compounds crates many defect sites significantly enhance the performance. • The Se-(CoFe)S 2 sample displays lower overpotential for OER and high specific capacities for supercapacitor. The strategy of constructing a three-dimensional hierarchically porous architecture with heterointerface and defects to rich the electrochemically active site, and rapid electron transfer has been considered as an effective strategy to achieve the excellent electrochemical performance in electrochemical energy storage and conversion. Herein, a Se-doped hollow heterostructure/defects Co-Fe sulfide (Se-(CoFe)S 2) box has been developed via a facile sulfurization-selenization treatment of hollow Co-Fe Prussian blue analogues precursor. Remarkably, the abundant hierarchical macro-mesopores of hollow Se-(CoFe)S 2 nanobox with excellent structural stability and unique electrical properties can not only effectively expose the electrochemically accessible active sites but also significantly improve the electrolyte transport and electron transfer, thus boosting electrochemical performances in oxygen evolution reaction (OER) and supercapacitors in alkaline media. For OER, the Se-(CoFe)S 2 electrocatalyst shows a small overpotential of 281 mV at 10 mA cm−2 and a low Tafel slope of 51.8 mV dec−1 as well as high stability. Furthermore, it also shows good performance for supercapacitors, suggesting its great potential as an efficient electrode for sustainable energy applications. Superb properties highlight the great prospects of PBA-based derivatives in applications of energy storage and conversion. Surface selenium doped hollow heterostructure/defects Co-Fe sulfide nanoboxes (Se-(CoFe)S 2) with unique morphology/electronic structure exhibits excellent electrochemical performances of OER and supercapacitors. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Novel uniform hollow mesoporous Mg 2 Si 3 O 6 (OH) 4 micro-nanosphere assembled by nanosheets has been prepared by controlling the amount of silica in the hydrothermal reaction. Then Mg 2 Si 3 O 6 (OH) 4 /GO micro-nanocomposite was prepared by a facile strategy, in which GO supports the framework and effectively avoid agglomeration of Mg 2 Si 3 O 6 (OH) 4 and GO. It exhibited the highly excellent selective adsorption performance for MB with much higher adsorption capacities than those of reported adsorbents, which could be used as a promising adsorbent for MB dye from pollutional water. • Novel uniform hollow mesoporous Mg 2 Si 3 O 6 (OH) 4 micro-nanosphere assembled by nanosheets was prepared. • GO supported hollow mesoporous Mg 2 Si 3 O 6 (OH) 4 nanocomposite was also prepared. • Formation mechanism of nanocomposite was proposed. • It exhibited the highly excellent selective adsorption performance for methylene blue. • The maximum adsorption capacity is much higher than those of reported adsorbents. Porous materials exhibit a superb adsorptive performance owing to the merits of large surface area. In this paper, a novel uniform hollow mesoporous magnesium silicate Mg 2 Si 3 O 6 (OH) 4 micro-nanosphere assembled by nanosheets has been prepared by controlling the amount of silica during the hydrothermal reaction. Then a novel nanocomposite for Mg 2 Si 3 O 6 (OH) 4 /GO was prepared by a facile strategy, in which graphene oxide (GO) serves as the support. This nanocomposite exhibited the highly excellent selective adsorption performance for MB with much higher maximum adsorption capacities of 909.1 mg/g, which is much higher than that of reported adsorbent materials. GO not only effectively avoids agglomeration of Mg 2 Si 3 O 6 (OH) 4 , but also possesses favorable synergistic adsorption with Mg 2 Si 3 O 6 (OH) 4. The adsorption process was found to comply with the pseudo-second-order rate equation and Langmuir adsorption model. The competitive adsorption, the effects of dosage, pH, temperature, ionic strength, adsorption mechanism and recycling performance were also investigated, respectively. Thermodynamic studies showed the adsorption process was endothermic, spontaneous and entropically driven. Considering of the above results in real water treatment and recyclability, this environmental friendly and high-efficient nanocomposite holds a potential application for removal of MB dye pollutant. [ABSTRACT FROM AUTHOR]

The aim of the study is to explore the efficacy and safety of dendritic cell-cytokine-induced killer cell (DC-CIK) immunotherapy combined with chemotherapy in the treatment of locally advanced gastric cancer (LAGC). Among 106 patients with LAGC, 53 received the treatment of oxaliplatin-5-fluorouracil chemotherapy (control group), while the remaining 53 received DC-CIK immunotherapy combined with chemotherapy (DC-CIK group). The short-term efficacy and the changes in immune function indexes (cluster of differentiation (CD)3+, CD4+, CD8+, CD4+/CD8+, and natural killer (NK) cells) were analyzed. The overall response rate (ORR) was 47.2% (25/53) and 41.5% (22/53), and the disease control rate (DCR) was 69.8% (37/53) and 50.9% (27/53), respectively, in the DC-CIK group and the control group. It could be seen that the ORR had no statistically significant difference between the two groups, while the DCR in the DC-CIK group was significantly better than that in the control group. After treatment, the proportions of CD3+ T lymphocytes, CD4+ T lymphocytes, CD4+/CD8+ cells, and NK cells obviously rose, while the proportion of CD8+ T lymphocytes obviously declined in the DC-CIK group compared with those in the control group. After treatment, the scores in the function module of the QLQ-C30 scale were greatly higher in the DC-CIK group than those in the control group, while the scores of loss of appetite, constipation, dyspnea, fatigue, pain, and sleep disorders in the symptom module were significantly lower in the DC-CIK group than those in the control group. The median survival time was 23.4 months and 18.6 months, respectively, in the DC-CIK group and the control group. The results of the log-rank test showed that the OS in the DC-CIK group was remarkably superior to that in the control group. DC-CIK immunotherapy combined with chemotherapy can improve the immune cell function, ameliorate the quality of life, and prolong the survival time of LAGC patients, with fewer adverse reactions. [ABSTRACT FROM AUTHOR]