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The magnetic skyrmions have received a lot of attention because they have potential applications in spin torque nano-oscillators. In this paper, we numerically and analytically study the dynamics of edge skyrmions in circular nano-pillar oscillators with perpendicular magnetic anisotropy (PMA) free layer and spin polarizer. Numerical simulations demonstrate that a steady edge skyrmion oscillation mode with GHz frequency can be driven by spin currents and magnetic fields. The oscillation frequencies in circular nano-pillars with different radius are analytically derived, which agrees well with the numerical results. In addition, the steady oscillations of edge skyrmions are also observed in elliptical nano-pillars, in which the oscillation frequencies strongly depend on the eccentricity and perimeter of the elliptical nanopillar. It is found that the oscillation frequency of this edge skyrmion can range from 1 GHz to 6.7 GHz. The line width is about 55 MHz.

The detection of H2O2 in milk was carried out using a CIC-biosensor based on collagen-immobilized catalase (CIC) and a dissolved oxygen probe. The CIC-biosensor response was fastest at pH 7.0 at 30 °C. Further, the biosensor exhibited responses over a H2O2 concentration range from 1.47 × 10−6 mol/L to 2.94 × 10−4 mol/L with response times of 20–120 s, and could be reused eight times. When the CIC biosensor was applied for the detection of H2O2 in milk, the recovery of H2O2 ranged from 83.4% to 95.8%. The biosensor can potentially be used for rapid detection of H2O2 in milk as a result of its sensitivity and rapid response time, easy preparation, and simple sample pretreatment.

In order to avoid defects (e.g. dust, scratch, static electricity) caused by manual detection, this research proposes a non-contact defect detection approach for circuit board through use of template matching method. In the proposed approach, images of both circuit board to be detected and circuit board selected as template are obtained respectively from multiple views. Then defect index (DI) of each view is constructed based on corresponding matching results between the image to be detected and the template image. Finally, total defect index is obtained by integrating all DI from multiple views, which can characterize the existence of defects in the circuit board (e.g. lack or wrong installation of components). The proposed approach is experimentally investigated to detect two surface defects on a circuit board. Results show that the two defects can be accurately detected with no false alarm by use the proposed method.

Challenges remain in engineering cardiac tissues with functional and morphological properties similar to those of native myocardium. In the current study, micropatterned fibrous mats are obtained by deposition of electrospun fibers on lithographic collectors to reproduce the anisotropic structure of myocardium, and carbon nanotubes are included in fibers to provide conductivities at the same level of cardiac muscles. The patterned mats are assembled layer-by-layer into patterned scaffolds for coculture of primary cardiomyocytes (CMs) with cardiac fibroblasts (CFs) and endothelial cells (ECs). CMs are organized along the fibers with clear cardiac strips of sarcomeric α-actinin and belt-like connexin-43, showing strong cellular extraction forces and intercellular communications. Compared with square and rectangle patterns, honeycomb (Hc)-patterned scaffolds shows higher ultimate tensile strength and strain to failure. The finite element analysis indicates no apparent stress concentration under stress application in the two orthogonal directions. The Hc-patterned coculture demonstrates significantly higher CM viabilities, deeper penetrations of cells into scaffolds, stronger expression of troponin I, connexin-43 and sarcomeric α-actinin by CMs and more abundant formations of capillary-like networks by ECs than other scaffolds. CMs on Hc-patterned scaffolds display spontaneous beating rates at 101±12times/min after coculture for 5days and remain synchronously beating at 94±8times/min after 15days, which is close to those of adult and neonatal rats. The layered and patterned coculture strategy achieves the spatial arrangement of multiple types of cells and vascularization potential, providing a biomimetic strategy for engineering functional cardiac patches in vitro.

The present generation of district heating (DH) technologies will have to be further developed into the 4th generation to fulfil the important role in future smart energy systems. At present, automatic meter reading systems have been installed in DH systems. These systems make hourly or even minutely meter readings available at low cost. However, the sheer quantity and complex of the data poses a challenge at various levels for traditional data analysis approaches. Data mining is a promising technology and is used to automatically extract valuable knowledge hidden in large amounts of data. To investigate the potential application of descriptive data mining techniques in DH systems, this study proposes a method based on descriptive data mining to improve the energy performance of DH substations. The proposed method consists of five steps: data cleaning, data transformation, cluster analysis, association analysis, and interpretation/evaluation. Data cleaning and transformation are implemented to improve data quality and transform data into forms that are appropriate for mining. Cluster analysis is performed to identify distinct operating patterns of substations. Based on each pattern, association analysis is then adopted to discover the unsuspected knowledge in the form of rules. Interpretation/evaluation is performed to select and interpret potentially useful rules. To demonstrate its applicability, the proposed method is used to analyze the datasets obtained from an automatic meter reading system at two substations in the DH system in Changchun, China. This application reveals that the method can effectively extract potentially useful knowledge and thereby provide essential guidance for the fault detection and operation optimization of DH substations.

Currently, due to high surface to volume ratio; large availability, rapid kinetics of adsorption and desorption and low cost, the exploitation of microbial biosorption of heavy metals is regarded as a reliable alternative compared to the conventional bioremediation approaches. In parallel with the increasing attractiveness of biosorption research, its pace of advance is also boosted. The barrier that prevent biosorption as an effective method from being applied into wastewater purification is listed, (1) There is not enough data on multi-component biosorption, (2) It remains to be seen that physical-chemical characteristics of different biomasses. (3) Studies on surface modification of strains for enhancement of heavy metals removal efficiency is lack. And extensive literatures involving the mechanism and model of biosorption for particular metal and microbial strains are not available. The present literatures lack systematization, the theory on interaction between lactic acid bacteria and Pb is far from complete. Therefore, the review tries to give a comprehensive explanation about the mechanism of Pb removal from Lactic acid bacteria and provide a brief overview of distinction between biosorption and bioaccumulation, biosorption technology, highlight the underlying features of biosorption and the various affecting factors such as pH, dose required, initial concentration, temperature, and treatment performance as a reference. Biosorption mechanisms can be briefly generalized into several pathways, which are ion exchange, complexation, precipitation, reduction and chelation. Many views holds that complexation is the major absorption mechanisms of Pb. Biosorption mechanisms can be roughly classified as biosorption and bioaccumulation, which have great differences between each other. Biosorption is metabolism-independent but fast, while bioaccumulation is metabolism-dependent but slow. The slight advantages of the bioaccumulation are the metabolite (lactic acid), lactobacillus surface-layers, enzymes and so on. Many factors can greatly affect adsorption process, different factors have different influence and the effects of pretreatment, pH and temperature are relatively greater. Desorption is not a fully reversible process of biosorption, but could not only achieve the goal of the recycle of microorganism, but also contribute to release of trace metal elements. Also the technologies for observation of biosorbents characterics and effect on the metal binding process are reviewed.

A concise and efficient method for the synthesis of etherified 3-(1H-1,2,3-triazol-1-yl)phenyl iodides from 1,4-disubstituted 1,2,3-triazoles under metal-free conditions has been developed. In the presence of ArI(OAc)2, a range of 1,2,3-triazole substrates that contain a hydroxy group underwent a direct O–H arylation and C–H iodination to afford functionalized 1,2,3-triazoles in good to excellent yields.

Background: Arabinoxylan was thought to have the potential to change lipid metabolism and redox homeostasis in human and animal. However, the effect of arabinoxylan on the liver damage induced by high-fat diet needs further exploiting.; Results: Six-weeks-old 30 male Sprague-Dawley Rats were assigned randomly to three groups (n = 10 per group), i.e. a control diet (CON) group, a high-fat diet (HF) group and a high-fat diet supplemented with arabinoxylan (6% AX, HF-AX) group. Results showed that final body weight and liver weight were similar in CON group and HF-AX group, but higher in the HF group. In serum, the HF-AX group showed lower triglyceride concentrations than did the HF group. In liver, higher lipoprotein lipase, hepatic lipase, total lipase, and acyl-CoA oxidase activities and lower triglyceride and cholesterol level were observed in the HF-AX group than in the HF group. For the redox homeostasis, arabinoxylan supplemented in HF increased T-SOD activity and GSH-PX activity and reduced MDA + 4-HNE level in liver and/or compared with those in the HF group. Lipid droplets and liver cell damage were observed in the HF group compared with the CON and HF-AX groups.; Conclusion: Arabinoxylan could improve lipid metabolic disorder and alleviate liver damage in rats induced by high-fat diet via activating lipid catabolism and suppressing lipid peroxidation. © 2017 Society of Chemical Industry.; © 2017 Society of Chemical Industry.

Silver-catalyzed direct lactonization of 1,4-disubstituted 1,2,3-triazole acids through C(5)–H acyloxylation is reported. This method provides a concise and efficient pathway to synthesize lactone-fused triazole derivatives, which were obtained in good to excellent yields at room temperature.

CuI-catalyzed selective Ullmann C–O coupling of 1,4-disubstituted 1,2,3-triazole bromides with phenols were achieved through the coordination of N(2) atom. The ortho C–Br bond in N(1) aryl can be selectively coupled with phenols, while other C–Br bonds remain inert, generating ortho aryloxyl 1,4-diaryl 1,2,3-triazoles.

Pd(OAc)2-catalyzed direct C–H arylation of an arene triazole template has been explored using the triazole ring as a directing group. The N(3)-ortho C–H bond on C(4) aryl of 1,4-disubstituted 1,2,3-triazoles can be selectively arylated, exclusively affording the expected structures. The diarylated products could be selectively formed when the triazole derivative beared a para substituent on C(4) aryl of the heterocycle, while the monoarylated target molecules resulted from substrates with an ortho or meta substituent.

Based on the excellent biocompatibility of collagen, collagen was extracted from pig skin by acid-enzymatic method. The films were prepared by the self-aggregation behavior of collagen, and the catalase was immobilized by adsorption, cross-linking and embedding. The experiment investigated the effects of glutaraldehyde on the mechanical properties, external sensory properties, and denaturation temperature of the films. The results showed that self-aggregating material could maintain the triple helix structure of pig skin collagen. The self-aggregation treatment and cross-linking treatment can improve the mechanical properties to 53 MPa, while the glutaraldehyde cross-linking agent can increase the denaturation temperature of the pig skin collagen self-aggregating membrane by 20.35% to 84.48 °C. This means that its application to immobilized catalase has better stability. The comparison shows that the catalase immobilized by the adsorption method has strong activity and high operational stability, and the cross-linking agent glutaraldehyde and the initial enzyme concentration have a significant effect on the immobilization, and the activity can reach 175 U g−1. After 16 uses of the film, the catalase was completely inactivated. This study provides a reference for the preparation of a catalase sensor that can be used to detect hydrogen peroxide in food by a catalase sensor.

Unmanned Aerial Underwater Vehicles (UAUVs) with multiple propellers can operate in two distinct mediums, air and underwater, and the system modeling of the autonomous vehicles is a key issue to adapt to these different external environments. In this paper, only a single set of aerial rotors with switching propulsion abilities are designed as driving components, and then a compound multi-model method is investigated to achieve good performance of the cross-medium motion. Furthermore, some additional variables, such as water resistance, buoyancy and their corresponding moments are considered for the underwater case. In particular, a critical coefficient for air-to-water switching is presented to express these gradually changing additional variables in the cross-medium motion process. Finally, the sliding mode control method is used to reduce the altitude error and attitude error of the vehicles with external environmental disturbances. The proposed scheme is tested and the model is verified on the simulation platform.

In this experiment, we studied the effect of poly(lactic acid)/poly(butylene adipate-co-terephthalate) (PLA/PBAT) blend films on the efficiency of passion fruit preservation at 20 &deg, C. The weight loss, shrinkage index, firmness, and total sugar of passion fruit packaged with PLA/PBAT films had no significant differences compared with PE films during 21 days (p &gt, 0.05). PLA/PBAT films can more effectively reduce the rising of ethanol content and delay the total acid, ascorbic acid, and sensory evaluation. Compared with unpackaged (CK) and polyethylene (PE) films, PLA/PBAT films are more conducive to preserve the overall flavor of passion fruit during storage time, in agreement with sensory evaluation, tested by E-nose, E-tongue, and GC-MS, which also proved that it can effectively maintain the edible quality of passion fruit during storage time. We believe that our study makes a significant contribution to literature because it paves the way to the generalization and application of packaging films based on composite antibacterial polymers and facilitates the commercialization of fresh passion fruit as an important health food.

In this research, chitosan (CS) and poly (vinyl alcohol) (PVA) were adopted as a material, methacryloyloxyethyl trimethyl ammonium chloride (DMC) was added in various concentrations and was treated ultrasonically for the formation of films with the use of the polymer blending method. The influences exerted by the ultrasonication period on PVA/CS/DMC antimicrobial active materials underwent material characteristic tests. The consequences revealed that at the break of the compound films, ultrasonication raised the elongation and tensile strength on the whole. Ultrasonication further or also enhanced the light transmittance performance and composite films&rsquo, barrier property. Furthermore, the compound film with a DMC concentration of 2% had good antibacterial properties, the film&rsquo, s inhibition rates against Staphylococcus aureus and Escherichia coli after ultrasonication were 79.23% &plusmn, 1.92% and 72.31% &plusmn, 1.35%, respectively.

In this study, the casting method was used to make chitosan (CS)/corn starch/cinnamaldehyde film, and the preservation performance of the film was examined. The results showed that the tensile strength of the film can reach to 31.24 &plusmn, 0.22 MPa when the mass ratios of CS, corn starch, and glycerin were 2.5%, 7%, and 0.5% respectively. The addition of cinnamaldehyde made the films have great inhibitory effect on Botrytis cinerea, Rhizopus, and Escherichia coli. In particular, the film had a significant fresh-keeping effect on strawberries, which reduced the loss of nutritional value, when aiming at soluble solids, titratable acid value, weight loss rate, and other indexes of strawberries. Thus, the films can slow down the physiological changes of strawberries and extend their shelf life to 11 days. Therefore, this work demonstrates the noteworthy potential of these novel films, incorporating natural antimicrobial compounds as innovative solutions to be used in active food packaging to extend the shelf-life of food products.

Collagens were extracted from grass carp skin (GCC), grass carp scales (GSC), and crucian carp skin (CCC) using an acid-enzyme combination method, and their characteristics and self-assembly properties were analyzed. Electrophoretic patterns characterized all three as type I collagens. An ultraviolet analysis identified the optimal wavelengths for collagen detection, while a Fourier transform infrared spectroscopy analysis confirmed the triple-helical structure of the collagens. The GCC, GSC, and CCC had denaturation temperatures of 39.75, 34.49, and 39.05 &deg, C, respectively. All three were shown to self-assemble into fibrils at 30 &deg, C in the presence of NaCl, but the fibril formation rate of CCC (40%) was slightly higher than those of GCC (28%) and GSC (27%). The GSC were shown to form a more strongly intertwined fibril network with a characteristic D-periodicity. The fish collagens extracted in this study have potential applications in the development of functionalized materials.

Radar servo system, as an important part of mechanic scanning radar and mechanism-phase scanning radar, plays an important role in the process of regular work. Aiming at the requirements of some complex application conditions for radar servo system, such as high overload, strong interference and fast response, this paper systematically analyzed the reliability of radar servo system based on FMECA model, and identified the risk links in its design and application process. Focusing on the weaknesses of radar servo system in telecommunication, structure and process, effects of optimization of driving mode chopper, optimization design of anti-interference, structure design of antenna pedestal and damage detection of servo system on the stability of radar servo system are explored, then methods which help to improve the reliability of servo system are presented and further verified by experiment and simulation. Results show that the presented methods in this paper can effectively improve the reliability of radar servo system, which provide important references for subsequent design and maintenance.

In this study, PLA/TiO2 composites materials were prepared via electrospinning and solution casting processes. By testing the mechanical properties, water contact angle, water vapor permeability, and solubility of the composite nanofibers and films, the comprehensive performances of the two types of nanocomposites were analyzed. The results show that maximum tensile strengths of 2.71 &plusmn, 0.11 MPa and 14.49 &plusmn, 0.13 MPa were achieved for the nanofibers and films at a TiO2 content of 0.75 wt.%. Moreover, the addition of TiO2 significantly cut down the water vapor transmittance rate of the nanofibers and films while significantly improving the water solubility. Further, the antibacterial activity increased under UV-A irradiation for a TiO2 nanoparticle content of 0.75 wt.%, and the nanofiber and films exhibited inhibition zones of 4.86 &plusmn, 0.50 and 3.69 &plusmn, 0.40 mm for E. coli, and 5.98 &plusmn, 0.77 and 4.63 &plusmn, 0.45 mm for S. aureus, respectively. Overall, the performance of the nanofiber was better than that of the film. Nevertheless, both the nanocomposite membranes satisfied the requirements of food packaging materials.

Drying characteristics and quality of apple slices were studied using microwave intermittent drying at different microwave power density (2.2, 3.5, 4.8, and 6.1 W/g), sample thickness (3, 5, 7, and 9 mm) and heating time in each cycle (4, 5, 6, and 7 s). Results showed that the approximate constant rate drying periods and falling rate drying periods were found in all the curves. The drying time decreased with increasing microwave power density and heating time in each cycle, while increased significantly with the growth of sample thickness. Weibull distribution model could fit the drying curves well in all conditions (R² > 0.99) with the scale parameter values changed from 45.88 to 206.08 min and the shape parameters values varied from 1.514 to 1.69. The moisture effective diffusivity calculated by Weibull model ranged from 0.3217 × 10⁻⁹ to 1.435 × 10⁻⁹ m²·s⁻¹. The flavor, texture and overall acceptability values displayed a decreasing tendency with the increase of microwave power density, while increased with the growth of thickness. And the shrinkage rates of apple slices showed a decline tendency with the increase of above parameters. PRACTICAL APPLICATIONS: Apple is a kind of popular and important fruits with high nutrient content, and it has been widely planted in China. Due to its high moisture content, fresh apples will subject to various deteriorative reactions during storage and thus lead to serious post‐harvest losses. Microwave drying technology has been widely used in dehydration of agricultural products in China because of the significant heating efficiency. However, the continuous microwave heating may easily cause the overheating of raw materials and undesirable changes in quality. Microwave intermittent drying (MID) was proposed on the basis of conventional microwave drying and regarded as an efficient processing method by solving the above issues. Currently this technology has been successfully applied to ginkgo fruits, yam and banana slices. Analyzing the effects of drying parameters on MID kinetics and quality of apple slices will have important significance for optimizing the processing efficiency and consumer acceptability of dried products.

The physical and antimicrobial properties of sodium alginate or sodium carboxymethylcellulose films containing cell-free supernatant of Lactococcus lactis ATCC 11454 were evaluated in this study. The antimicrobial activity of the films against Staphylococcus aureus ATCC 6538, and Escherichia coli ATCC 25922 was evaluated. Cell-free supernatants were obtained by centrifugation and filtration of Lactococcus lactis cultures in MRS broth; the filtrates were freeze-dried, and rehydrated (4, 8, or 12 mg/mL) to produce collagen film. The thickness, tensile strength, color, moisture content, solubility, and water vapor permeability of the films were measured to examine the effects of cell-free supernatants on film matrices. Noticeable antimicrobial activity was observed against Staphylococcus aureus, and Escherichia coli upon the addition of 12 mg/mL cell-free supernatants. Our results indicate that the incorporation of cell-free supernatant changed the physical properties of the edible films. Gradual and significant (p 0.05) increase in color difference and solubility were observed with the addition of increasing concentrations of cell-free supernatant. Antimicrobial films were brown in color and with variable moisture contents. Sodium alginate films were better than sodium carboxymethylcellulose films for most of the evaluated parameters. In summary, collagen films containing cell-free supernatants are interesting alternative natural antimicrobial films for functional food packaging.

A facile and efficient method for direct C–H formylation of phenolated 1,4-disubstituted 1,2,3-triazoles using DMSO as the formyl source has been developed. The reaction proceeded smoothly under metal-free conditions with good functional group tolerance and high selectivity co-controlled by the triazole ring and hydroxyl group. Synopsis Direct C–H formylation of phenolated 1,4-disubstituted 1,2,3-triazoles using DMSO as the formyl source has been developed under metal-free conditions with good functional group tolerance and high selectivity.

In this study, we developed edible films designed to control the growth of Staphylococcus aureus in tryptone soya agar. We analyzed three edible film-forming substrates: sodium alginate, sodium carboxymethylcellulose, and collagen. In addition, we evaluated Lactococcus lactis, which produces bacteriocin and lactic acid. Lactococcus lactis-containing edible films were constructed via tape-casting method. Optical, mechanical, and antimicrobial properties of the edible films were measured to examine the effects of Lactococcus lactis on film matrices. Further, we determined the survival of Lactococcus lactis after the film-drying process and viability of Lactococcus lactis stored for 24 days at 4 °C. Our results indicate that incorporation of Lactococcus lactis changed the physical properties of edible films. Films containing Lactococcus lactis showed reduced gloss and transparency. There are insignificant modifications were observed in terms of tensile strength and elongation at break. At 4 °C, used to represent a low-temperature environment, the growth of Staphylococcus aureus was inhibited for 7 days in edible films populated with Lactococcus lactis. The viability of Lactococcus lactis was higher in sodium alginate/sodium carboxymethylcellulose films, and was highest in films composed of sodium alginate and methylcellulose. In summary, our study provides a new method for functional food packaging.

International audience; In this study, we developed and tested various antimicrobial polyvinyl alcohol (PVA)/tea polyphenol (TP) composite films intended to extend the shelf life of packaged strawberries. Each PVA/TP film with volumetric ratios of 10/0, 9/1, 8/2, 7/3, 6/4 and 5/5 was prepared using tap-casting methods and characterized with respect to its infrared spectrum, tensile strength, oxygen permeability, water solubility, biodegradation, and antimicrobial properties. The effects of the various composite films were subsequently evaluated based on the fruit's weight loss, decay rate, firmness, pH, titratable acidity, and soluble solids. The results indicated that thePVA/TP-8/2 composite film effectively retarded the fruit's weight and firmness loss. In addition, the PVA/TP-8/2 composite film significantly retarded the fruit's titratable acid and soluble solid loss and limited microbial proliferation. Among the various antimicrobial composite films tested, the PVA/TP-8/2 composite film exhibited significant potential as a packaging material that would extend the shelf life of strawberries.

Field-free magnetization switching by in-plane current injection via spin–orbit interactions in heavy-metal/ferromagnet bilayer systems is of great interest for applications of spin–orbit torque (SOT). Here, we demonstrate theoretically how to deterministically switch the magnetization of CoFeB with a tilted perpendicular magnetic anisotropy (PMA) by using the SOT effect from the viewpoint of energy landscape. It is found that magnetization switching is dependent both on the polar angle θ and the azimuthal angle φ of the tilted PMA. A tiny remnant magnetization component that deviates away from the film plane during the spin current pulse impulsion period is a key point for the subsequent switching. The underlying mechanism is attributed to the shift of PMA energy barrier with the magnetization angle, which dominates the state of the tiny magnetization component and thereafter the bipolar deterministic switching. Based on the simulation results, a phase diagram of deterministic switching regarding θ and φ is established. Moreover, the positive and negative critical switching current densities are demonstrated to exhibit an astroid-like characteristic as a function of θ. This study provides a fundamental insight into the nature of SOT-induced deterministic switching with the tilted PMA method.

With the rapid development of UHV, the demand for power line inspections continues to increase. The optical electric field method is the current cutting-edge insulator detection method, which is accurate. Mounting it on an unmanned aerial vehicle (UAV) can expand detection advantages, improve detection efficiency, and ensure safe electricity use. UAVs are currently developing rapidly, and there are many types of UAVs on the market. Due to the principle of the electric field method for detecting insulators and the real environment of power inspection site, there are certain requirements for UAVs. Therefore, we are striving to compare and analyze the UAVs on the market, and conclude that the optimal UAV choice for power line inspection is the quad-rotor UAV. Finally, the application will be promoted to provide reference and ideas for the inspection of oil pipelines. Introduction.

International audience; In this study, biopolymer-based antimicrobial fibrous membranes constituted by polylactic acid (PLA) and ultrasonically dispersed ZnO nanoparticles (NPs) were developed by electrospinning. The morphology, mechanical properties, thermodynamics and antimicrobial properties of membranes with different ZnO NPs content were comprehensively studied. The results showed that the best performance was achieved when the content of ZnO content was 0.5 wt% (PLA/ZnO-0.5%). Specifically, the tensile strength and elongation at break of the composite membrane were 6.85 ± 0.19 MPa and 74.90 ± 0.59%, respectively, and the inhibition zones of Escherichia coli and Staphylococcus aureus were 15.02 ± 0.18 mm and 14.74 ± 0.06 mm, respectively. In addition, an appropriate ultrasonication time of 45 min improved the thermal, ultraviolet (UV) barrier, and antibacterial properties of the composite membrane. At the 45 min ultrasonication time, the inhibition zone of PLA/ZnO-0.5% against Escherichia coli and Staphylococcus aureus was 18.11 ± 0.15 mm and 15.80 ± 0.11 mm, respectively. Therefore, PLA/ZnO-0.5% can be applied in food packaging to provide an antibacterial effect and UV light barrier.

The key to addressing the challenges facing cardiac tissue engineering is the integration of physical, chemical, and electrical cues into scaffolds. Aligned and conductive scaffolds have been fabricated as synthetic microenvironments to improve the function of cardiomyocytes. However, up to now, the influence of conductive capability and inner structure of fibrous scaffolds have not been determined on the cardiomyocyte morphologies and beating patterns. In the current study, highly aligned fibers were fabricated with loaded up to 6% of carbon nanotubes (CNTs) to modulate the electrical conductivity, while blend and coaxial electrospinning were utilized to create a bulk distribution of CNTs in fiber matrices and a spatial embedment in fiber cores, respectively. Conductive networks were formed in the fibrous scaffolds after the inoculation of over 3% CNTs, and the increase in the conductivity could maintain the cell viabilities, induce the cell elongation, enhance the production of sarcomeric α-actinin and troponin I, and promote the synchronous beating of cardiomyocytes. Although the conductivity of blend fibers is slightly higher than that of coaxial fibers with the same CNT loadings, the lower exposures to CNTs resulted in higher cell viability, elongation, extracellular matrix secretion and beating rates for cardiomyocytes on coaxial fibers. Taken altogether, core-sheath fibers with loaded 5% of CNTs in the fiber cores facilitated the cardiomyocyte growth with a production of organized contractile proteins and a pulsation frequency close to that of the atrium. It is suggested that electrospun scaffolds that couple conductivity and fibrous structure considerations may provide optimal stimuli to foster cell morphology and functions for myocardial regeneration or establishment of in vitro cardiomyocyte culture platform for drug screening.

A facile and efficient method for the regioselective acylation of 1,4-disubstituted 1,2,3-triazoles by using a Pd-catalyzed C–H bond-activation strategy with tert-butyl hydroperoxide (TBHP) as an oxidant and an aromatic aldehyde as the acyl source has been developed. This synthetic approach was applied to a wide range of substrates to generate various 1,2,3-triazole derivatives that contain the diaryl ketone scaffold.

Many conductive scaffolds were fabricated to mimic the topography of the cardiac microenvironment in vitro in order to improve the performance of engineered cardiac tissues. This study fabricated aligned poly(lactic-co-glycolic acid)/multiwalled carbon nanotube fibers by electrospinning. The Young's modulus and conductivity were significantly greater on poly(lactic-co-glycolic acid) fibers with 3% multiwalled carbon nanotubes compared to others. Topographical cues and conductivity were applied to investigate the combined effect on cardiomyocyte behavior. Neonatal rat cardiomyocytes cultured on the conductive fibers maintained their viability, induced cell elongation, and enhanced sarcomeric α-actinin and troponin I production in cardiomyocytes. The results indicate that poly(lactic-co-glycolic acid)/multiwalled carbon nanotube composite fibers have great potential for cardiac tissue engineering.

The objective of this study was to determine the impact of wheat bran and its main polysaccharides on intestinal bacteria and gene expression of intestinal barrier function relevant proteins. Thirty freshly weaned male piglets were assigned randomly to five dietary treatment groups with six piglets per group. Accordingly, five synthetic diets including a basal control diet without fiber components (CON), wheat bran diet (10% wheat bran, WB), arabinoxylan diet (AX), cellulose diet (CEL) and combined diet of arabinoxylan and cellulose (CB) were studied. The piglets were fed ad libitum for 30 d. Lower Escherichia coli (E. coli) populations in WB group and higher probiotic (Lactobacillus and Bifidobacterium) populations in groups fed diets containing arabinoxylan (WB, AX and CB) were observed and compared with CON group. Compared with CON group, the gene expressions of cystic fibrosis transmembrane conductance regulator (CFTR), calcium-activated chloride channel regulator 1 (CLCA1) and voltage-gated chloride channel 2 (CIC2) were suppressed in the WB group. And wheat bran down-regulated gene expression of pro-inflammation (TNF-α, IL-1β, IL-6) and TLRs/MyD88/NF-κB pathway compared with CON group. In conclusion, wheat bran and its main polysaccharides could change intestinal microflora and down-regulate the gene expression of intestinal barrier function relevant proteins in the distal small intestinal mucosa.

The establishment of a reliable in vitro liver model for drug screening remains challenging with respect to tethering the growth of hepatocyte spheroids and adapting to the current high-throughput system. In the current study, short fibers are utilized as scaffolds for the generation of size-controlled hepatocyte spheroids that recapitulate in vivo hepatic phenotypes and functions. The spheroid formation is modulated by the length and galactose/RGD grafts of short fibers, and short 50 μm long fibers motivate the spheroid formation with optimal hepatic function. Short fibers distribute throughout the entire spheroid for tethering hepatocyte growth to form compact spheroids. Compared with scaffold-free spheroid culture on agarose-coated plates, the spheroid culture with short fibers achieves higher clearance rates of model drugs and provides a better prediction of the in vivo drug clearance rate with a correlation value of 0.886. In addition, the drug metabolism capability is highly sensitive to the inducers and inhibitors of metabolizing enzymes, and the responsiveness is maintained during 20 days of culture, exhibiting an efficient in vitro model for determining drug-drug interactions. Therefore, the spheroid culture with short fibers provides an easily manipulated strategy to maintain hepatocyte functions for a prolonged period and enable ready deployment in conventional multiwell plates and diverse organ-on-a-chip devices for high-throughput drug screening.

Graphical abstract, Highlights • PVA/AgNPs nanofibers were grafted with 3,3′,4,4′-benzophenone tetracarboxylic acid. • The water vapor transmittance and mechanical properties were improved. • It retained >70% of its original OH⋅ radical and H2O2 charging capacity after 7 cycles. • It showed higher filtration efficiency and antibacterial activity., In this study, poly(vinyl alcohol) (PVA) membranes containing Ag nanoparticles (AgNPs) were prepared by electrospinning and grafted copolymerization with 3,3′,4,4′-benzophenone tetracarboxylic acid (BPTA) to provide better mechanical properties, lower water vapor transmittance, and higher antibacterial activity (against Staphylococcus aureus and Escherichia coli) than the PVA/AgNPs membrane. The PVA/AgNPs/BPTA membrane showed higher antibacterial activity than the other membranes, and it produced inhibition zones with diameters of 18.12 ± 0.08 and 16.41 ± 0.05 mm against S. aureus and E. coli, respectively. The PVA/AgNPs/BPTA membrane was found to be capable of promoting reactive oxygen species (ROS) formation under both light and dark conditions. Cycling experiments performed following ROS quenching showed that the best-performing composite membrane retained >70% of its original OH⋅ radical and H2O2 charging capacity after seven cycles. In the filtration test, the electrospun nanofibrous membranes showed high filtration efficiencies of 99.98% for sodium chloride (NaCl). In addition, these membranes maintained a relatively low pressure drop of 168 Pa with a basis weight of 2.1 g m−2. Thus, the PVA/AgNPs/BPTA membrane was concluded to be a promising medical protective material offering the benefits of structural stability and reusability.

In this study, two different species of lactic acid bacteria (LAB) (Lactobacillus plantarum and Pedocococcus pentosaceus) with high exopolysaccharide (EPS) yield were selected from a pickled water. Further, edible films based on cassava starch (CS) were developed containing LAB, and sodium carboxymethylcellulose (CMC). After addition of probiotics, the antioxidant activity of the composite film was significantly enhanced. Further, as the probiotic content increased, the antioxidant activity continuously increased. Moreover, L. plantarum showed uniform distribution in the CS/CMC matrix, forming a denser structure, which effectively blocked the penetration of water molecules and exhibited ultraviolet protection. Finally, due to the intermolecular interaction between probiotics and the CS/CMC matrix, the water vapor and light transmission rates were reduced, effectively blocking water and light to prevent lipid oxidation deterioration in food packaging. Banana shelf life has qualitatively improved with 2% LAB added composite film and its application in food packaging has been affirmed.

In this study, secondary pyrolysis oil-based drilling cuttings ash (OBDCA-sp) was used to remediate chromium (Cr)-contaminated soil. The effects of the OBCDA-sp mesh, OBCDA-sp dosage and soil moisture content on the removal of Cr (VI) were investigated. Subsequently, a kinetic experiment was conducted where the pseudo-first-order and pseudo-second-order kinetic models both fitted well on OBDCA-sp with the adsorption process of Cr (VI) in soil. The change of the chromium form indicated that the addition of OBCDA-sp transformed Cr from an effective state to a stable form, reducing its mobility and bioavailability. X-ray diffraction and Fourier transform infrared spectroscopy analysis were used to verify the potential mechanism of Cr (VI) removal; Ba, Fe, S, and P elements in OBCDA-sp were observed to play a significant role in the reduction of Cr (VI). The results from this study indicate that OBCDA-sp could be an emergent and promising alternative for the remediation of Cr-contaminated soil.

An antibacterial and anti-oxidation composite film was prepared by a casting method using sodium alginate (SA) and apple polyphenols (APPs) as the base material and glycerol as the plasticizer. Silver nanoparticles (AgNPs) were deposited by ultrasonic-assisted electrospray method. The degree of influence of the addition ratio of SA and AgNPs and different ultrasonic time on the mechanical properties, barrier properties, optical properties, and hydrophilicity of the composite film was explored. The composite films were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed that the SA: AgNPs ratio of 7:3 and the ultrasonic time for 30 min have the best comprehensive performance, and SA/AgNPs/APP films showed the lowest water vapor permeability value of 0.75 &times, 10&minus, 11 g/m&middot, s&middot, Pa. The composite film has good strength and softness, with tensile strength (TS) and elongation at break (E) at 23.94 MPa and 29.18%, respectively. SEM images showed that the surface of the composite film was smooth and the AgNPs&rsquo, distribution was uniform. The composite film showed broad antibacterial activity, and the antibacterial activity of Escherichia coli (92.01%) was higher than that of Staphylococcus aureus (91.26%). However, due to the addition of APP, its antioxidant activity can reach 98.39%, which has a synergistic effect on antibacterial activity. For strawberry as a model, the results showed that this composite film can prolong the shelf life of strawberries for about 8 days at 4 &deg, C, effectively maintaining their storage quality. Compared with the commonly used PE(Polyethylene film) film on the market, it has a greater fresh-keeping effect and can be used as an active food packaging material.

Response Surface Methodology (RSM) was used to assess the optimal conditions for a Water/Oil/Water (W/O/W) emulsion for encapsulated nisin (EN). Nano-encapsulated nisin had high encapsulation efficiencies (EE) (86.66 &plusmn, 1.59%), small particle size (320 &plusmn, 20 nm), and low polydispersity index (0.27). Biodegradable polyvinyl alcohol (PVA) and polyacrylate sodium (PAAS) were blended with EN and prepared by electrospinning. Scanning electron microscopy (SEM) revealed PVA/PAAS/EN nanofibers with good morphology, and that their EN activity and mechanical properties were enhanced. When the ultrasonication time was 15 min and 15% EN was added, the nanofibers had optimal mechanical, light transmittance, and barrier properties. Besides, the release behavior of nisin from the nanofibers fit the Korsemeyer&ndash, Peppas (KP) model, a maximum nisin release rate of 85.28 &plusmn, 2.38% was achieved over 16 days. At 4 &deg, C, the growth of Escherichia coli and Staphylococcus aureus was inhibited for 16 days in nanofibers under different ultrasonic times. The application of the fiber in food packaging can effectively inhibit the activity of food microorganisms and prolong the shelf life of strawberries, displaying a great potential application for food preservation.

The skyrmion-based spin-torque nano-oscillator is a potential next-generation nano microwave signal generator. In this paper, the self-sustained oscillation dynamics of magnetic skyrmions are investigated in a nanodisk with synthetic antiferromagnetic (SAF) multilayer structure, in which the skyrmion Hall effect can be effectively suppressed. An analytical model based on the Thiele equation is developed to describe the dynamics of a pair of skyrmions formed in the SAF nanodisks. Combining the analytical solutions with the micromagnetic simulations, we demonstrate that circular rotations with opposite directions for a skyrmion pair could be suppressed by increasing the antiferromagnetic (AF) coupling in a nanopillar with dual spin polarizers. However, a stable circular rotation can be achieved in a nanopillar with a single spin polarizer, in which one skyrmion plays as a master whose rotation is driven by spin torque, while the other skyrmion is a slaver whose motion is dragged by the AF coupling between the two free layers. Moreover, we found that the effective mass factor in the SAF structure rather than the gyrotropic torque plays the dominant role in the circular rotation of skyrmions. The rotation orbit radius and frequency gradually increase with the decrease of damping factor and increase of applied current strength.

Mesenchymal stem cells (MSCs) have been widely used for regenerative therapy. In most current clinical applications, MSCs are delivered by injection but face significant issues with cell viability and penetration into the target tissue due to a limited migration capacity. Some therapies have attempted to improve MSC stability by their encapsulation within biomaterials; however, these treatments still require an enormous number of cells to achieve therapeutic efficacy due to low efficiency. Additionally, while local injection allows for targeted delivery, injections with conventional syringes are highly invasive. Due to the challenges associated with stem cell delivery, a local and minimally invasive approach with high efficiency and improved cell viability is highly desired. In this study, we present a detachable hybrid microneedle depot (d-HMND) for cell delivery. Our system consists of an array of microneedles with an outer poly(lactic-co-glycolic) acid (PLGA) shell and an internal gelatin methacryloyl (GelMA)-MSC mixture (GMM). The GMM was characterized and optimized for cell viability and mechanical strength of the d-HMND required to penetrate mouse skin tissue was also determined. MSC viability and function within the d-HMND was characterized in vitro and the regenerative efficacy of the d-HMND was demonstrated in vivo using a mouse skin wound model.

The ortho- C–H bonds at C(4)-aryl of 1, 4-disubstituted 1, 2, 3-triazoles were regioselectively alkoxylated in good to excellent yields with under the directing of the triazole ring. Some products were found to exhibit strong antifungal capacity to fight against root-rot disease of Panax notoginseng by testing the minimum inhibitory concentration (MIC).

Three dimensional (3D) deposit-scale modelling was used to identify exploration targets at depth and evaluation of mineral resources including 3D geometry and attribute models. Constructing 3D deposit-scale model need to combine exploration boreholes, cross-sections, and geochemistry assays additional mining dataset. The Shanggong gold deposit is a magmatic hydrothermal deposit with an orogenic setting, and it is located in the south margin of North China Craton. On basis of the geological features of the Shanggong gold deposit, the 3D geology model and attribute modelling aims at potential targets identification and mineral resource estimation adopting different mining and exploration datasets and uncertainty analysis in 3D space. The methodology is summarized as follows: 1) the 3D geological bodies, such as stratum, fault, ore bodies model, constructed using GoCAD software, an initial range of 3D model is 15 × 13 × 3 km3; 2) Ordinary Kriging and discrete smooth interpolation (DSI) methods were used to analyze and identify the trend of the mineralization (Au) features in 3D space combined boreholes and the primary geochemical haloes dataset, and the Au/Pb ratio model is constructed using primary geochemical haloes data with DSI interpolation method; 3) the grade simulation modelling and assessing the uncertainty of the geometry and feature models using the geostatistical method. The results show as follows: 1) the high gold grade value zones are associated with intrusion and NE-trending and NNE-trending cross fault structures; 2) the high gold grade value blocks of Au/Pb ratio can be used to depict mineralization zones; 3) Ordinary Kriging and DSI methods can show the trend of the attribute model; 4) the simulation results can characterize the uncertainty of the 3D model through uncertainty analysis.

Protection of water environments is an important part of overall environmental protection; hence, many people devote their efforts to monitoring and improving water quality. In this study, a self-adapting selection method of multiple artificial neural networks (ANNs) using hyperspectral remote sensing and ground-measured water quality data is proposed to quantitatively predict water quality parameters, including phosphorus, nitrogen, biochemical oxygen demand (BOD), chemical oxygen demand (COD), and chlorophyll a. Seventy-nine ground measured data samples are used as training data in the establishment of the proposed model, and 30 samples are used as testing data. The proposed method based on traditional ANNs of numerical prediction involves feature selection of bands, self-adapting selection based on multiple selection criteria, stepwise backtracking, and combined weighted correlation. Water quality parameters are estimated with coefficient of determination R 2 ranging from 0.93 (phosphorus) to 0.98 (nitrogen), which is higher than the value (0.7 to 0.8) obtained by traditional ANNs. MPAE (mean percent of absolute error) values ranging from 5% to 11% are used rather than root mean square error to evaluate the predicting precision of the proposed model because the magnitude of each water quality parameter considerably differs, thereby providing reasonable and interpretable results. Compared with other ANNs with backpropagation, this study proposes an auto-adapting method assisted by the above-mentioned methods to select the best model with all settings, such as the number of hidden layers, number of neurons in each hidden layer, choice of optimizer, and activation function. Different settings for ANNS with backpropagation are important to improve precision and compatibility for different data. Furthermore, the proposed method is applied to hyperspectral remote sensing images collected using an unmanned aerial vehicle for monitoring the water quality in the Shiqi River, Zhongshan City, Guangdong Province, China. Obtained results indicate the locations of pollution sources.

In this study, gelatin (GEL) extracted from grass carp and tea polyphenols (TP) were encapsulated in chitosan (CS) nanoparticles using an innovative electrospray based ionic gelation method. CS-TP nanoparticles were fully optimized in terms of encapsulation efficiency and polydispersity. The average diameter of the optimal CS-TP nanoparticles was 205 ± 14 nm, and encapsulation efficiency of 66.7% ± 9.9% was achieved. The effects of CS-TP nanoparticles on the physicochemical properties of the GEL/CS-TP composite films were studied. Our results showed that the combination of CS-TP and grass carp gelatin (GEL) can not only weaken the strong interaction between GEL and TP, but also improved the swelling and mechanical properties of GEL. Furthermore, GEL/CS-TP30% composite film showed strong barrier and good mechanical properties, low UV transmission, exhibited high free radical-scavenging ability and prolonged the stability of an easily oxidizable oil for over 14 days, making it a suitable film for use as an edible packaging material. Keywords: Gelatin, Chitosan, Tea polyphenols, Composite films

The effective manipulation of skyrmion motion by magnetic field gradients introduces the technological possibility with skyrmion as information carriers for spintronic applications. Recent studies indicate that the skyrmion Hall effect can be suppressed in a synthetic antiferromagnetic (SAF) multilayer structure driven by a spin polarized current. In this paper, an analytical model based on Thiele equation is developed to describe the properties of a skyrmion pair in a SAF structure driven by a magnetic field gradient. Combining the analytical solutions with the micromagnetic simulation results, we demonstrate the essential dynamic features of the skyrmion pair as a function of AF coupling and magnetic field gradients, revealing that the skyrmion pair motion could be suppressed by increasing the interlayer antiferromagnetic coupling.

Modification of functional properties by glycosylating with polysaccharides is an effective solution to improve the internal disadvantages of native proteins. Generally, protein glycosylation belongs to the first stage of the Maillard reaction in essence. Dry-heating, wet-heating, and their combination are the major methods for the preparation of protein-polysaccharide conjugates (PPC). Spectrophotometry, spectroscopy, electrophoresis, calorimetry, chromatography, and mass spectrometry are confirmed to be the most effective methods for the identification of PPC. After glycosylation, functionalities of the native protein, including solubility, rheological properties, emulsifying properties, foaming properties, gel property, film-forming properties, thermal stability, antioxidant activity, allergenicity, and antibacterial properties, are improved. The PPC is extensively used as an encapsulation or a delivering material in order to improve the bioaccessibility of bioactive compounds in food system. Some new applications in food processing could be explored using PPC as an ingredient based on the improved functional properties, such as 3-dimensional printing food, gelled food, and colloid food. Furthermore, the model of protein glycosylation and the application of PPC in food processing could be extended to other protein modification to broaden the exploitation of native protein resource for the processing of novel foods.

International audience; Nonvolatile magnetic random-access memory is one of the most promising memory candidates to meet the requirements of high-density and low-power data storage. Downsize scalability and energy efficiency of conventional memory-unit cells with elliptic shape, however, remain matters of great concern. The development of alternative memory-unit-cell architecture that would potentially enhance the performance of practical devices is thus particularly interesting for applications. Here the magnetic configurations for nanoring magnetic tunnel junctions with an in-plane magnetic storage layer are studied by micromagnetic simulation, revealing that, for an appropriate ring width, the outer diameter can be scaled down to less than 20 nm, where the magnetic onion configuration becomes energetically favored. We also study the spin-transfer-torque switching process and dynamic resistance state diagram with respect to the applied magnetic field and spin-polarized current. A low switching-current density is demonstrated. The results indicate the advantage of using nanoring magnetic tunnel junctions as memory units, which may provide an alternative solution for high-storage-density and low-power-consumption nonvolatile memory.

The ferromagnetic resonance induced by spin-transfer torque (ST-FMR) is important for microwave detectors, as it can convert an ac microwave signal directly into a dc signal that can be easily measured. However, so far only one resonance mode could be detected for a given external magnetic field, resulting in a relatively low efficiency. This study considers ST-FMR in geometrically confined nanoring magnetic tunnel junctions (NR-MTJs), in which $t\phantom{\rule{0}{0ex}}w\phantom{\rule{0}{0ex}}o$ resonance modes are observed at a given magnetic field. This result might significantly improve the efficiency of such microwave detectors, by means of a dual-mode detection configuration.

As an advanced manufacturing technology that has been developed in recent years, three-dimensional (3D) printing of macromolecular materials can create complex-shaped components that cannot be realized by traditional processing. However, only a few types of macromolecular materials are suitable for 3D printing: the structure must have a single function, and manufacturing macromolecular functional devices is difficult. In this study, using poly lactic acid (PLA) as a matrix, conductive composites were prepared by adding various contents of multi-walled carbon nanotubes (MWCNTs). The printability and properties of MWCNT/PLA composites with different MWCNT proportions were studied by using the fused deposition modeling (FDM) processing technology of 3D printing. The experimental results showed that high conductivity can be realized in 3D-printed products with a composite material containing 5% MWCNTs, its conductivity was 0.4 &plusmn, 0.2 S/cm, its tensile strength was 78.4 &plusmn, 12.4 MPa, and its elongation at break was 94.4% &plusmn, 14.3%. It had a good melt flow rate and thermal properties, and it enabled smooth printing, thus meeting all the requirements for the 3D printing of consumables.