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TiO2–Y2O3–ZrO2composite ceramics exhibit excellent abrasion resistance, corrosion resistance, and high-temperature resistance, making them vital structural-functional materials in ceramics and refractories. The key to preparing high-quality TiO2–Y2O3–ZrO2ceramic powders lies in controlling the agglomeration rate, which can be optimized by choosing an appropriate drying method. This study utilized microwave drying techniques to dehydrate TiO2–Y2O3–ZrO2ceramic powders. It was found that the average drying rate is proportional to initial masses, initial moisture contents and microwave heating powers. To describe the drying process, four models—the Quadratic, Wang and Singh, Modified Page, and Page—were employed. The best model for the drying process was the Modified Page model. The specimens were analyzed to assess the alterations in the samples pre and post-drying by scanning electron microscopy and Fourier transform infrared spectroscopy. The findings revealed that microwaves can hasten the drying process of TiO2–Y2O3–ZrO2and enhance its spread. Utilizing Fick's second law, the effective diffusion coefficient was ascertained, showing an inverse proportionality to the sample mass, and a proportionality to the microwave heating power and initial moisture content. Using the Arrhenius exponential model, it was ascertained that the microwave drying process's activation energy stands at 13.81834 W/g. This paper demonstrates that microwave drying effectively achieves efficient drying and lays the theoretical and experimental groundwork for the microwave heating and drying of other powdered materials.

• The effects of EMV parameters (frequency, current density and magnetic flux density) were investigated. • Experiments and simulations are used to investigate the mechanism of EMV. • Effective grain refinement can be achieved only when the relative displacement falls within the range of 102–103 μm. • The proposed approach can be used to the continuous casting of other alloys. The effect of electromagnetic vibration (EMV) on the solidification structure of Cu-15Ni-8Sn alloy during bulk solidification and the upward continuous casting was investigated experimentally and numerically. The bulk solidification results indicated that in the case of B = 0.5 T and J = 1.27 × 105 A/m2, the most effective grain refinement frequency was at f = 10 Hz, where fine non-dendrites were obtained. The solidification structure became coarser at f = 0.1 Hz and f = 1 Hz compared to the case of f = 10 Hz, while no grain refinement was observed at f = 100 Hz. The numerical simulations showed that at f = 10 Hz, the strong melt convection surrounding the primary solid phase promotes the diffusion of the rejected solute, consequently, resulting in a reduction of the solute boundary layer, which leads to the decrease in the nucleation-free zone (NFZ) and the grain refinement. Additionally, the most effective grain refinement frequency transformed to 1 Hz when the electromagnetic force was reduced by five times. Moreover, we proposed that the most effective grain refinement frequency range aligns with the EMV-induced relative displacement in the range of 102–103 μm. Finally, the upward continuous casting was conducted to validate the relative displacement range, and the experimental results matched well. [Display omitted] [ABSTRACT FROM AUTHOR]

Cu–15Ni–8Sn alloy is commonly utilized in various applications because of its exceptional strength, elasticity, and softening resistance. Ti microalloying has been employed to enhance the mechanical properties of Cu–15Ni–8Sn alloy. By adding 0.5 wt% Ti, the peak-ageing tensile strength, microhardness, and elastic modulus of the Cu–15Ni–8Sn alloys reach 1401.3 MPa, 479.3 Hv, and 154.7 GPa, respectively, representing the greatest comprehensive performance reported in previous literature. Additionally, the Ti microalloying significantly enhances the softening resistance of Cu–15Ni–8Sn alloys. After ageing at 400 °C for 10 h, the tensile strength of the Cu–15Ni–8Sn-0.5Ti alloy decreases by only around 150 MPa, whereas the alloy without Ti addition experiences a decrease close to 350 MPa. Quantitative analysis reveals that the observed improvements can be attributed to the Ti microalloying inhibiting the dislocation annihilation and the formation of discontinuous precipitation during the ageing process, while simultaneously promoting the precipitation of Ni3Ti. This study provides a theoretical basis for preparing a high-performance Cu–15Ni–8Sn alloy by microalloying.

The magnetic immiscible copper matrix alloys are extensively industrial applications due to their comprehensive properties such as high strength, high conductivity, high thermal conductivity and excellent magnetic permeability. Here, we investigated the effects of the addition of Co and Al elements on the microstructural evolution of magnetic Cu–Fe alloys (CFAs) and comprehensive properties after annealing under the static magnetic field (SMF). The results show that the microalloying was effective in enhancing the mechanical and magnetic properties but negative for the electric conductivity. The addition of Co element significantly suppressed the grains recrystallization of CFAs during the annealing process and improved the thermal stability of CFAs. Al elements homogeneously dispersed in the sample. SMF facilitated the nucleation and precipitation processes of the secondary precipitated particles in the Cu-rich matrix through the introducing the extra magnetic Gibbs free energy and also promoted the structural transformation of the secondary precipitated particles from FCC to BCC. This work indicates that SMF can be effectively used to modify the magnetic materials with exceptional comprehensive properties during the solid state phase transformation process. It also provides valuable guidance for the development of novel materials with superior comprehensive performance.

In the present study, the effect of the alternative magnetic field (AMF) on the metal pool shape, primary carbides formation, and mechanical properties during vacuum arc remelting (VAR) process was investigated by experiments and numerical simulations. Without AMF, the original depth of the molten pool was 87.74 mm. The application of the AMF decreased the depth of the metal pool, to various degrees (86.46 mm at 40 Gs 0.5 Hz, 78.96 mm at 40 Gs 0.1 Hz, 69.82 mm at 40 Gs 0.05 Hz). As a consequence, the primary carbides became more refined average size reduced by 20.66%∼25.72%. After modification, uniformly distributed hardness and improved wear resistance was achieved. Meanwhile, compared with 0.5 and 0.1 Hz cases, the strengthening effect was more obvious at 0.05 Hz. The numerical simulation results showed that, the AMF and the melting current in the molten steel produced Lorentz force, which caused the horizontal circulation. Therefore, the temperature of metal pool became more homogenized under the horizontal circulation. When the frequency was 0.05 Hz, the horizontal circulation in liquid steel was more intense, which makes the temperature field more uniform. Horizontal circulation can also reduce the segregation of alloying elements, which restrains the precipitation condition and refines primary carbides. The hardness uniformity can also be attributed to the uniform distribution of alloying elements. The improvement in wear resistance is attributed to the refinement of the primary carbide, thereby reducing the occurrence of primary carbide spalling during friction.

The AlCoCrFeNi2.1eutectic high-entropy alloy (Ni2.1EHEA), as an exemplary representative of the high-entropy alloy family, has garnered significant research attention owing to its exceptional comprehensive properties. In this study, we investigated the influence of various growth velocities on the microstructure, lamellar spacing, and mechanical properties of the Ni2.1EHEA. We observed that at lower growth velocities, the structure consisted of an alternating face-centered-cubic (FCC) phase and B2 phase lamellae aligned in a single direction, with the lamellae orientation parallel to the direction of the heat flow. The yield strength increased with the growth rate, while the ultimate tensile strength decreased with increasing the growth velocity. Ductility remained relatively consistent, and a double yield phenomenon was observed in the elastic-plastic deformation region. Under conditions of high growth velocities, the microstructure transitioned from a single-directional full lamellar structure to a multi-stage lamellar arrangement. The most favorable comprehensive mechanical properties were achieved at a growth rate of 200 μm/s, resulting in a yield strength of 450 MPa, an ultimate tensile strength of 1092 MPa, and a remarkable ductility of ∼32% in the directionally solidified samples—double that of the arc-melted sample. The evolution law of directional solidification structures under the coupling effect of different magnetic fields and different growth rates was studied. The interaction of the thermoelectric-magnetic force and thermoelectric-magnetic convection and the potential mechanism of microstructure evolution under the effect of magnetic field were deeply analyzed. The results reveal that at a growth rate of 2 μm/s, the spacing between eutectic layers decreases as the magnetic induction intensity increases, leading to the transformation of some regular layers into spherical layers. Similarly, at a growth velocity of 10 μm/s, the eutectic structure exhibited a Columnar-to-equiaxed transition (CET). However, as the growth rate further increases, the limited exposure time to the magnetic field prevented significant structural changes.

Rhenium, a unique engineering material with the second highest melting point of all metals, has significant application potential in harsh service environments, and thus evaluating its mechanical responses under shock loadings is of great importance. Through molecular dynamic simulations, we have systematically investigated the effect of crystallographic orientations on the mechanical responses of single crystalline rhenium under shock compression. We have obtained the P–V/V0,Up-P, P-T, and Us-UpHugoniot relations, and evaluated their anisotropies. The particle velocity, Pzz, and shear stress show orientation dependent when tracing the shock profiles at different time, and the difference is particularly pronounced for shear stress, resulting from the atomic arrangement in the HCP crystal structure of rhenium. The plastic deformations mechanisms of rhenium single crystal under shock loadings are revealed as the emission of dislocations and the generation of disordered atoms, and the influence of shock intensity on the plastic deformation mechanism has been systematically studied. The results presented in this work not only shed light on the effect of crystallographic orientations on the mechanical responses of monocrystalline rhenium under shock compression, but also offers fundamental insights for understanding the shock induced plastic deformation mechanisms, which could provide a valuable supplement to the investigations of mechanical properties pertaining to rhenium.

Natural phytochemicals have attracted increasing attention because of their promising ability to tackle bacteriotoxin-induced public safety concerns. However, it is unclear how natural phytochemicals regulate the intestinal barrier dysfunction caused by bacteriotoxin, such as staphylococcal enterotoxin A (SEA). This study aims to illustrate the in vitroand in vivoprotective mechanism of epigallocatechin gallate (EGCG) on SEA-triggered intestinal barrier damage and inflammation. Results show that EGCG alleviates intestinal barrier damage by effectively inhibiting SEA-induced intestinal permeability increase, tight junction protein and mucin loss, and intestinal cell apoptosis. EGCG also reduces intestinal inflammation by suppressing the TLR4-NF-κB/MAPKs-NLRP3 pathway. Importantly, EGCG reverses gut microbiota dysbiosis and short-chain fatty acid (SCFA) content decrease induced by SEA. It is worth noting that this study also detects the direct interaction between the phytochemical and virulence factors and finds that EGCG effectively not only inhibits the secretion of SEA but also binds with the secreted SEA to attenuate its toxicity. Taken together, EGCG mitigates SEA-induced intestinal barrier dysfunction via gut microbiota SCFA-mediated TLR4-NF-κB/MAPKs-NLRP3 inflammatory cascade inhibition. Overall, this research provides enlightening insight into the application of bacteriotoxin-targeting natural compounds in the field of food safety and human wellness.

Wrinkling is a significant defect during forming of thin-walled metallic tubes via free-bending forming (FBF) technology. Thus, it's quite important to predict the wrinkling in the tubes to improve the quality of the final products. Accordingly, new theoretical and numerical frameworks were proposed for predicting the wrinkling of the tubes manufactured via FBF technology. The theoretical wrinkling prediction model is based on the energy criteria and the thin shell theory. The numerical prediction model was constructed on the ABAQUS/Implicit FE code. Besides, The Knoop microhardness test characterized the anisotropy of the tube. The tube's imperfection was introduced to the numerical model through pure bending buckling analysis. The bending experiments were conducted to verify the results obtained from the proposed theoretical and numerical frameworks and showed good agreement with them. Furthermore, it was noticed that the additional axial force in the FBF process reduces the tube's ability to resist wrinkles. The larger additional axial force makes tubes more sensitive to imperfection in free bending than in other bending technologies. The numerical prediction model with the perfect tube exhibits good accuracy in predicting the initiation of the tube wrinkling in free bending but not in terms of the wrinkling shape. The model considering the imperfection can predict the onset and development of wrinkling properly.

This study presents a one-surface plasticity constitutive model combined with phenomenological and micromechanical damage models to be applied to the large plastic deformation during tube hydroforming. These factors lead to simulating the Bauschinger effect and transient behavior in large plastic strain ranges and predicting fracture onset. By using the integration approach, a numerical integration algorithm of implementation by explicit schemes was carried out. A comparison of several cyclic loading tests between experiments and numerical simulation was accomplished. The accuracy of these models is verified, which could be expanded to a large strain range forming process. Adopting the proposed models, finite element modeling is performed in the tube hydroforming process. The simulation and experimental results comparison showed that the proposed framework accurately predicted the tube formability in the hydroforming process.

In three and six-axis free-bending equipment, the deformation zone length (A) is a fixed mechanical structure parameter modified when the relevant structure is redesigned and manufactured. In this study, a six degree of freedom (6-DOF) parallel mechanism was used as the control mechanism of the bending die, and a new method of changing the deformation zone length (A) was proposed. Firstly, an idealized geometric model of free bending-based active motion was established. Then, the influence of the deformation zone length (A) on the bending moment and the bending radius of the tube was analyzed. In addition, the finite element simulation and a kinematic model of free bending-based active motion controlled by the 6-DOF parallel mechanism were established, and bending processes of the SS304 tube with different deformation zone lengths were investigated. Afterwards, the impact of the deformation zone length (A) on the bending radius, bending moment, wall thickness, and motion of the parallel mechanism were analyzed. Finally, experiments were carried out on the free-bending equipment based on the 6-DOF parallel mechanism. Experiments verified the rules in the theoretical analysis, finite element simulation, and kinematic simulation.

The current work investigated the impact of transverse static magnetic field (TSMF) with varied magnetic flux density (MFD) on cleanliness and microstructure of laboratory scale electroslag remelted H13 die steel. The inclusion morphology and microstructure evolution of electroslag remelted ingots were examined utilizing scanning electron and optical microscopes, respectively. The number and size of inclusions in ingots were detected using the FEI Aspex Explorer. The results demonstrated that the number/size of inclusions in H13 electroslag remelted ingots were decreased as the MFD of applied TSMF increased. This resulted from the application of the TSMF, which produced the thinner liquid melting film (LMF), smaller droplets, and shallower metal molten pool, strengthening the kinetic conditions for inclusion migration to the slag-metal interface and the removal process. When the MFD of the applied TSMF was higher (95 mT and 140 mT), the LMF became thinner, the droplets became smaller, and the metal pool became shallower were more visible. Moreover, the metal pool became shallower and the local solidification time became shorter after applying TSMF with larger MFD, resulting in finer dendritic structure and carbides.

The relationship between government subsidies and the total factor productivity of enterprises has been a controversial issue. Recent literature has stressed that the lack of efficient institutional settings increases the tendency to rent-seeking and reduces the productivity performance of enterprises. Moreover, the productivity performances of enterprises vary with their life cycles. In this light, since increasing attention has been directed at the role of government subsidies recently, we have measured the impacts of government subsidies on the total factor productivity of enterprises by exploring the role of the rent-seeking activities and life cycle. Then, a 16-year panel dataset (1998–2013) was organized using enterprise data, which included enterprises whose annual main business income is not less than 5 million yuan from the Chinese equipment manufacturing industry. We found that government subsidies negatively affect the total factor productivity of enterprises and specifically those enterprises in the growth stage. Next, the intermediary analysis confirmed that government subsidies induce unproductive rent-seeking activities, rather than productive rent-seeking activities. Finally, the implications of government subsidy policies for supporting the total factor productivity of enterprises are discussed.

This investigation determined the creep-fatigue cyclic-life (Nf) saturation effect for the DZ445 superalloy with 16–128 min dwell time at 900 °C and total strain range of 1.6%. When the dwell time exceeds 8 min, the mechanical response including maximum stress response, hysteresis loop, plastic strain range, and stress relaxation amount at characteristic cycle are also saturated with dwell time gradually. The Nfsaturation effect is also reflected in the creep- and ductile-dominated fracture modes. This critical phenomenon is closely related to the dynamic equilibrium reached between the superdislocations of a/2[101] in γˊ precipitation and the formation of the dislocation networks. While the rupture time is increased continuously with dwell time, which could be better used as an evaluation index when the cyclic life is saturated. The Nfsaturation effect can not only reduce the cost of tests with long-dwell time, but also provide the guidance for creep-fatigue safety design.

Dinuclear and mononuclear cycloplatinated(II) complexes (1–3and 4–6) with formulas [Pt(bt)(μ-L)]2and Pt(bt)(L) [bt = 2-phenylbenzothiazole, μ-L = deprotonated diphenyl(2-(5-phenyl-4H-1,2,4-triazol-3-yl)phenyl)phosphine oxide derivatives for L1–L3, and L = deprotonated 3-(2-(diphenylphosphino)phenyl)-5-phenyl-4H-1,2,4-triazole derivatives for L4–L6] have been successfully synthesized and systematically characterized. Single-crystal X-ray analysis demonstrates that these complexes exhibit distorted square-planar geometries around Pt(II) centers. There are no apparent intermolecular π–π and Pt–Pt interactions owing to the presence of bulky ligands. Therefore, these complexes achieve excellent monomeric emission in solution, PMMA films, and the solid state with a photoluminescence quantum yield (Φ) up to 67.3% in the solid state. The photophysical behaviors associated with theoretical investigations reveal that the emissions of these complexes possess primarily a 3LC feature together with some 3MLCT character.

Staphylococcal enterotoxins (SEs) secreted by Staphylococcus aureusfrequently contaminate food and cause serious foodborne diseases but are ignored during food processing and even cold-chain storage. Notably, SEs are stable and resistant to harsh sterilization environments, which can induce more serious hazards to public health than the bacterium itself. Therefore, it is necessary to develop promising strategies to control SE contamination in food and improve food safety. Natural products not only have various pharmaceutical properties, such as antimicrobial and antitoxin activities, but they are also eco-friendly, safe, nutritive, and barely drug-resistant. Here, the hazards of SEs and the promising natural compounds with different inhibitory mechanisms are summarized and classified. The key points of future research and applications for natural products against bacterial toxin contamination in food are also prospected. Overall, this review may provide enlightening insights for screening effective natural compounds to prevent foodborne diseases caused by bacterial toxins.

This study aims at investigating the impact of using the Magnetorheological Elastomers (MREs) medium to improve the formability of T-shaped Inconel 718 tubes during the bulging process. Besides, the influence of the punch size and the intensity of the magnetic field on the branch height and wall thickness distribution of the T-shaped Inconel 718 tubes are also explored. The results showed that the parts formed by the punch with a length of 5 mm in the pressurization zone have better forming quality. The external magnetic field can promote a high branch, and by increasing the intensity of the magnetic field, the branch height was increased and then decreased. At the same time, the magnetic field reduced the amount of material accumulation between the guiding zone and the bulging zone. Besides, it promotes the material in the guiding zone to enter the bulging zone and improve the bulging ability of the T-shaped tube.

A transverse static magnetic field (TSMF) was superimposed during electroslag remelting (ESR) process to regulate the shape of metal pool, the eutectic carbides morphology as well as the mechanical properties of electroslag remelted M2 high-speed steel (HSS) in current study. The metal pool became shallower and flatter after applying a 65 mT TSMF. Moreover, refined eutectic carbides and solidification structure (tended to grow axial) of the ESR ingot were obtained, together with uniform/improved mechanical properties (hardness, wear). Modifications of the morphology of metal pool and grain growth angle under the TSMF were attributed to a periodic electromagnetic excitation effect on droplets transition characteristics, which changed the drop path of the droplets (single to multiple drop) and homogenized the temperature distribution in metal pool. In addition, local solidification time (LST) became shorter and the number of inclusions ((Ti, V)N–Al2O3and (Ti, V)N) which acted as heterogeneous nuclei for eutectic carbides formation increased (the inclusions also became finer) due to TSMF, resulting in the refinement of the eutectic carbides in ESR ingots.

Introduction: Recently, deep learning based methods have become an important approach to the accurate analysis of medical images. Materials and Methods: This paper provides a comprehensive survey of the most important deep learning based methods that have been developed for medical image processing. A number of important contributions made in the last five years are summarized and surveyed. Results: Specifically, deep learning-based algorithms developed for image segmentation, image classification, registration, object detection and other important problems are reviewed. Conclusion: In addition, an overview of challenges that currently exist in the field and potential directions for future research is provided at the end of the survey.

Recently, oral deliverable strategies of multiple nutraceuticals for ulcerative colitis (UC) mitigation have attracted increasing attention. This study aimed to fabricate facile oral assemblies loaded with egg-white-derived peptides (EWDP) and curcumin based on carboxymethyl chitosan (CMCS) and an γ-cyclodextrin metal–organic framework (MOF). Herein, outer CMCS could coassemble with EWDP (both nutraceuticals and building blocks) into cobweb-like fibrils to promote bridging with inner MOF via coordinative noncovalent interactions (hydrogen bonding, hydrophobic interaction, and electrostatic interaction). Compared with conventional γ-cyclodextrin/MOF-based composites, the above coassembly could also endow the biocompatible assemblies with superior nanoscale colloidal properties, processing applicability (curcumin storage stability, bioaccessibility, and aqueous solubility), and bioactivity. Moreover, the oral synergism of EWDP and curcumin (initially nonsynergistic) for UC mitigation was achieved by alleviating inflammatory damage and gut microbiota imbalance. Overall, the novel assemblies could be a promising amplifier and platform to facilitate oral formulations of various nutraceuticals for food processing and UC relief.

The bent double-ridged rectangular tube (DRRT) with high forming quality is helpful to improve the microwave transmission accuracy. For reducing the cross-sectional deformation in the H-typed bending process, in addition to using rigid mandrel to support the inside of tube, ridge groove fillers are also added to restrict the deformation of ridge grooves. Because of the change of stress and strain state of bent tube in bending, rigid mandrel retracting and specially twice-springback stages, and the springback of fillers, the cross-sectional deformation of tube in each stage may be different. Therefore, based on the ABAQUS platform, the finite element models (FEM) for H-typed bending, mandrel retracting and twice-springback stages of H96 DRRT with fillers were established and validated. It is found that, for the height and width deformation of tube and spacing deformation of ridge grooves, retraction of mandrel can make the distribution of these deformations more uniform along the bending direction. The first springback can reduce these deformations significantly, which should be emphasized. But the second springback only increases them by less amount, which can be ignored. The smaller height deformation of ridge groove and filler can be neglected.

Abstract

The cotton‐based metal–air batteries without any catalyst are constructed. Especially, the continuous electrolyte flowing depends on the capillary force and the gravity from the height difference between the inlet and outlet. The performance of the cotton‐based metal–air batteries under 2 mol L−1NaOH or NaCl solutions is compared. The Al–air battery performance in the NaOH solution is better, while the Mg–air battery performance in the NaCl solution is the best. Considering the battery performance and cost, the alkaline cotton‐based Al–air battery is investigated for the subsequent experiments. The Al–air battery performance is evaluated under the different cotton cloth makeups, NaOH concentrations, height differences between the inlet and outlet. The results show that under the conditions of the cotton makeup (20 (warp) × 60 (yarn)), 4 mol L−1NaOH and 60 mm height difference, the battery performance is optimal, with the peak power density of 12.33 ± 0.38 mW cm−2and limiting current density of 35.28 ± 0.73 mA cm−2. To apply the cotton‐based Al–air battery, the two‐battery stack connected in series powers 15 light‐emitting diodes. The experiments demonstrate the cotton‐based Al–air battery without catalysts owns low cost and high power output, which has great potential as a micropower device. The cotton‐based metal–air batteries with the height differences from the inlet and outlet are constructed. The electrolyte flow depends on the capillary force with the gravity. The metal–air batteries performance under the alkaline or saline solutions is compared. Then, the alkaline Al–air batteries performance is evaluated under the different cotton cloth makeups, NaOH concentrations, and height differences.

Novel hetero-binuclear platinum complexes (HBC-Pt(II)-M(II), M = Ca(II), Mg(II), Zn(II), and Cd(II)) have been synthesized by the reaction of the corresponding precursors [Pt(ppy)(μ-Cl)]2with (2-(1H-tetrazol-5-yl)phenyl)diphenylphosphine oxide (TTPPO). The X-ray structures of the complexes show that two ancillary ligands TTPPO in the square-planar Pt(II) moiety act as a quadridentate chelating agent for the other metal center, eventually forming a distorted octahedral configuration. There are no significant π–π interactions and Pt–M metallophilic interactions in the crystal lattice, due to the steric hindrances associated with the rigid octahedral structure together with the bulky TTPPO. Consequently, HBC-Pt-M complexes show monomer emission characteristics with quantum yields up to 59% in powder, suggesting their great potential for practical applications. DFT and TD-DFT calculations on HBC-Pt-Zn reveal that the phosphorescence can be ascribed to intraligand charge transfer (3ILCT) combined with some metal-to-ligand charge transfer (3MLCT) in the Pt(ppy) moiety, which is consistent with the observations from the photophysical investigations.

Carbon paper has been widely used as a flow-through electrode to deliver the reactants through the electrodes in microfluidic fuel cells (MFCs). This electrode architecture can utilize the interior area in porous electrodes. Considering its disadvantages, such as a few functional groups, low specific surface area, and poor wetting property, it is necessary to actively treat the carbon paper. We study how the two activation methods, i.e., air annealing and acid oxidation, affect the contents of surface functionality, redox activity of iron ions, cathode resistance, and performance of MFCs. Our conclusion is that the two methods should be coupled together to achieve optimal surface physical and electrochemical properties: 303.23 ± 3.09 mW cm–3in volumetric power density and 1541.75 ± 134.17 mA cm–3in volumetric limiting current density, which are 1.57 and 1.75 times higher than that of a MFC with an untreated carbon paper cathode, respectively.

The stability of the high-oleic characteristic of tobacco (Nicotiana tabacum) transformants obtained by silencing of microsomal Ω-6 desaturase (FAD2) was investigated when grown at low temperature. Results showed that oleic acid content in total leaf lipids, individual leaf lipids and total seed lipids of transformants decreased drastically at low temperature, with a corresponding increase of polyunsaturated fatty acid contents. The decrease of oleate was caused by neither the restoration of FAD2transcripts nor the disappearance of small interference RNA. A significant increase of hexadecadienoic acid and hexadecatrienoic acid was observed in MGDG (monogalactosyldiacylglycerol) of transformants grown at lower temperature. Hexadecadienoic and hexadecatrienoic acids, typical fatty acids in MGDG, are produced through the activity of Ω-6 desaturase in plastids (FAD6). The significant increase of Hexadecadienoic and hexadecatrienoic acids suggested the involvement of FAD6 and/or other desaturases in the lipid desaturation of transgenic plants under lower temperature, leading to a significant decrease of oleate in plant cells. These results suggested that the activities of plastidic desaturases must be, at least partially, responsible for the instability of the high-oleic characteristic of FAD2-silenced plants.

In this work we are concerned with an efficient numerical solution of a perfectly matched layer (PML) system for a Maxwell scattering problem. The PML system is discretized by the edge finite element method, resulting in a symmetric but indefinite complex algebraic system. When the real and imaginary parts are considered independently, the complex algebraic system can be further transformed into a real generalized saddle-point system with some special structure. Based on an crucial observation to its Schur complement, we construct a symmetric and positive definite block diagonal preconditioner for the saddle-point system. Numerical experiments are presented to demonstrate the effectiveness and robustness of the new preconditioner.

Coatings containing Fe-Si or Si particles were electrodeposited on 3.0%(mass fraction) Si steel sheets. The surface morphology, the cross-section and the silicon content of coating have been investigated, respectively. It was found that the number of particles on the coating surface and cross-section significantly decreased with increasing silicon content in the applied particles, leading to a decrease of the silicon content of coatings. About 10.2% silicon content of coatings deposited with Fe-30%Si particles can be obtained, whereas that for Si particles was only 2.9% at a particle concentration of 100 g/L and current density of 2 A/dm2. This is mainly attributed to the conductivity of applied particles. High conductivity can promote the co-deposition of the particles. With increasing silicon content in the particles, their conductivity decreased sharply, resulting in the decrease of silicon content of coatings. Present work may initiate a new method to modify the particle content of the composite coatings viachanging the conductivity of the particles during the composite electrodeposition. In this paper, a possible mechanism was proposed to explain the phenomena.

The comprehensive utilization of food-derived nutraceuticals with different polarities has been extremely restricted by their poor bioavailability and coexistence in a single system. This study aimed to fabricate a self-assembly of amphiphilic nanoparticles (NPs) for the hydrophilic EWDP and hydrophobic curcumin based on the carboxymethyl chitosan (CMCS) shell and γ-cyclodextrin (γ-CD) core. Notably, EWDP could cooperate with CMCS to yield superior colloidal properties with an excellent curcumin aqueous solubility and co-encapsulation capacity (>10%) for the NPs (pH 2.0–7.0). This phenomenon was mainly ascribed to the additional hydrogen-bonding network and hydrophobic interaction introduced by EWDP. Besides, the overall antioxidant activity, bioaccessibility, gastrointestinal stability, and Caco-2 cell absorption properties were significantly improved in the presence of EWDP (>20% increase). Therefore, EWDP could function as both a potential affinity agent and a nutrition enhancer to expand the co-delivery applications for diverse nutraceuticals with promising oral bioavailability enhancement in food and pharmaceutical areas.

AbstractBallistic impact characteristics on the flat-nose projectile penetrating the concrete and soil compound target are studied. The deformation process and failure zone in the target are described by numerical simulation with finite element software. The results show that penetration depth, residual velocity and deceleration amplitude of flat-nose projectile increase with initial velocity. The features of concrete target after impact are approximately in agreement with experimental results. And the cracks and the tensile crush zone formed during penetration could characterize the damage and failure of target. Meanwhile, terminal ballistic characteristics of flat-nose projectile into single soil layer are studied to compare with that of concrete compound target. The results show that the overload of projectile penetrating hard-soil is only one-third of that of concrete compound target with low velocity. Reversely, the duration of the former is more than five times as long as the latter, and the rebound velocity of projectile penetrating soil medium is greater than the concrete compound target.

Glioma is one of the most common primary brain tumors. Despite surgical resection, radiotherapy, and chemotherapy, the prognosis of patients with malignant glioma remains poor. Programmed cell death 5 (PDCD5) is a newly described pro-apoptotic protein. Our previous study showed that PDCD5 downregulation in gliomas was associated with higher pathological grade. Here, we investigated the effect of PDCD5 on chemosensitivity of glioma cells and its mechanism. We demonstrated that overexpression or knockdown of PDCD5 had no significant effect on the proliferation of glioma cell lines (U87, U251, and T98G) in the absence of chemotherapeutic agents. However, PDCD5 overexpression effectively sensitized U87 cells to chemotherapeutic drugs (cisplatin, carboplatin, and vincristine) in a concentration-dependent manner, while its knockdown resulted in decreased chemosensitivity in U251, T98G, and U87 cells. Importantly, expression of PDCD5 also markedly inhibited tumor cell proliferation and colony formation in the presence of low doses of cisplatin. Furthermore, we found that PDCD5 expression promoted cisplatin-induced apoptosis, increased markedly the activation of caspase-3 and caspase-9, and decreased significantly the ratio of Bcl-2/Bax proteins, but had no effect on the activation of caspase-8. Taken together, our findings indicate that PDCD5 promotes chemosensitivity by activating mitochondria-related apoptotic pathway, and that the combination of PDCD5 and chemotherapeutic drugs such as cisplatin, is expected to be an effective therapeutic strategy for the malignant glioma.

Post-Translational Modifications (PTMs) play most important roles in the accomplishment of biological processes and molecular functions. It is challenging to identify two PTMs for a tandem mass spectrum. In this paper, we proposed a new algorithm to detect two PTMs with unknown types. First, we constructed a Pair of Peak Set (PPS) which is composed of pairs of peaks that have the highest sum of intensities. Second, we revealed the relationship between PPS and the whole experimental spectrum. Third, a series of logic conditions was proposed to detect PTMs from a MS/MS spectrum. Finally, we used a scoring function to rank the candidate hits. We applied the method to a large MS/MS data set and the experimental results demonstrated that the proposed method achieved better performance of identifying any types of PTMs in a blind mode than current existing methods.

Tandem mass spectrometry is a popular tool for the identification of peptide sequences. In this paper, we present a method for a rapid generation of short peptide sequences via tandem mass spectrometry based on a graph search method. The approach takes advantage of several pairs of peaks that have high intensities. We proposed a Pair Peak value Set (PPS) and used the pair peak values of highest intensities as the root of a tree. The other nodes are viewed as the reference nodes to search the most promising path. We aimed to determine the peptide sequences for MS/MS spectra that have low signal-to-noise ratios. Our experiment on 2420 experimental MS/MS spectra with two PTMs shows that our algorithm achieves better accuracy than the PepNovo approach with higher efficiency.

A contact map is a key factor representing a specific protein structure. To simplify the protein contact map prediction, we predict the inter-residue contact clusters centred at the groups of their surrounding inter-residue contacts. In this paper, we adopt a Support Vector Machine (SVM)-based approach to predict the inter-residue contact cluster centres. The input of the SVM predictor includes sequence profile, evolutionary rate and predicted secondary structure. The SVM predictor is based on hydrophobic cores that may be considered as locations of the inter-residue contact clusters. About 35% of clustering centres of inter-residue contacts can be predicted accurately.

In this paper, we developed a new method that progressively constructs and updates a set of alignments by adding sequences in a certain order to each of the existing alignments. Each of the existing alignments is modelled with a profile Hidden Markov Model (HMM) and an added sequence is aligned to each of these profile HMMs. We introduced an integer parameter for the number of profile HMMs. The profile HMMs are then updated based on the alignments with leading scores. Our experiments on BaliBASE showed that our approach could efficiently explore the alignment space and significantly improve the alignment accuracy.

Abstract: Polycystic ovary syndrome (PCOS) is associated with the spontaneous development of an aberrant heterogeneous hormonal environment that thought to be related to multiple genetic or environmental factors remain undefined. Previous studies indicated that IL-1a gene C (-889) T, a polymorphism of the gene encoding a protein which involved in various immune responses, inflammatory processes and hematopoiesis, and is associated with PCOS. A total of 205 PCOS patients and 177 healthy controls were included in this study that used PCR-RFLP to detect C (-889) T variant of IL-1a gene. Clinical measures determined previously were included in the SPSS analysis. The results showed that the presence of IL-1a gene C (-889) T polymorphism in PCOS and healthy controls in Chinese women was not significantly different when studying genotype and allele frequencies. (Genotype: χ2 = 4.62, df = 2, P = 0.10; allele: χ2 = 1.35, df = 1, P = 0.25). Furthermore, no association was found between metabolic parameters observed and IL-1a genotypes in PCOS patients in this study. In conclusion, IL-1a gene C (-889) T polymorphism does not appear to be risk factor for PCOS in this population of Chinese women.

AbstractThe economic growth of the country is linked with the development of the telecommunications industry. While most of the developed countries already have liberalized their telecom markets for open competition during 1980s and 1990s, this process is still under progress in developing countries of the world. The approach varies vastly among different countries due to different social and economic conditions, however, countries can learn from each other’s experiences to review their policies to get the objectives of full competition, universal service, protection of consumer interests, and deployment of advanced services. This paper compares the different policies for the development of telecommunications industries in China and Pakistan and also makes some suggestions for the forthcoming converged world from the experience of developed countries. The main focus of this paper is on competition and liberalization policies. Pakistan has taken revolutionary steps to bring competition to its telecom industry by adopting the approach of full market liberalization as compared with China’s gradual and controlled approach. New entry in Pakistan has been facilitated by all regulatory and policy means to attract private sector investment. China is trying to protect government-owned telecom operators by restricting entry in this sector due to concerns of Universal Service and foreign companies’ dominance of telecom industry. China is trying for fair domestic competition while Pakistan has adopted the approach of free competition. It is obvious from some economic and telecom indicators that telecom industry is exponentially growing after the liberalization and de-regularization of telecom industry in Pakistan The establishment of an independent regulator and the early promulgation of long-awaited Telecom Law are must for China. Both of these countries need more expertise and competency to accommodate convergence in reforms to facilitate the penetration of innovative technologies and services in their telecom industries.

Stochastic Context-Free Grammars (SCFG) has been shown to be effective in modelling RNA secondary structure for searches. Our previous work (Cai et al., 2003) in Stochastic Parallel Communicating Grammar Systems (SPCGS) has extended SCFG to model RNA pseudoknots. However, the alignment algorithm requires O(n ⁴) memory for a sequence of length n. In this paper, we develop a memory efficient algorithm for sequence-structure alignments including pseudoknots. This new algorithm reduces the memory space requirement from O(n⁴) to O(n²) without increasing the computation time. Our experiments have shown that this novel approach can achieve excellent performance on searching for RNA pseudoknots.

Through the first-principles calculations, we studied the atomic structure of polar CuInSe2 (001) surface. It is revealed that polar CuInSe2 (001) surface has different atomic structure for different atom-terminated surface models. Before and after relaxation, the atomic structure of different atom-terminated surface models is various. Bond lengthens are also changed.

The spin-related transport properties of graphene nanoribbons with zigzag edges which are partially coupled to Au linear-chain electrodes have been investigated by using non-equilibrium Green's function in combination with the density-functional theory. The results show that the partial contact with the electrodes will break the spin degeneracy, leading to the completely spin-polarized transport. Meanwhile, the spin-related properties are obviously dependent on the electrodes contact positions. For the boron doped graphene nanoribbons, the spin polarized effect is enhanced.

In this paper, the effect of H and F decoration on the growth of silicon vacancy on (100) surface in diamond has been studied. It is revealed that, the formation energy of SiV centers on (100) surface in diamond under different H/F coverages (1/4, 1/2, 3/4, and 1 ML) depending on the growth environment are various. SiV centers are more easily formed decorated with F in F-rich growth environment. Due to the different electronegativity of H and F, the growth of SiV centers is different. It plays a critical role for improving the growth of related color centers in and beyond the field of growth and application of color centers to the experimentalists.

Supplemental Digital Content is available in the text

An important but difficult problem in proteomics is the identification of post-translational modifications (PTMs) in a protein. In general, the process of PTM identification by aligning experimental spectra with theoretical spectra from peptides in a peptide database is very time consuming and may lead to high false positive rate. In this paper, we introduce a new approach that is both efficient and effective for blind PTM identification. Our work consists of the following phases. First, we develop a novel tree decomposition based algorithm that can efficiently generate peptide sequence tags (PSTs) from an extended spectrum graph. Sequence tags are selected from all maximum weighted antisymmetric paths in the graph and their reliabilities are evaluated with a score function. An efficient deterministic finite automaton (DFA) based model is then developed to search a peptide database for candidate peptides by using the generated sequence tags. Finally, a point process model—an efficient blind search approach for PTM identification, is applied to report the correct peptide and PTMs if there are any. Our tests on 2657 experimental tandem mass spectra and 2620 experimental spectra with one artificially added PTM show that, in addition to high efficiency, our ab-initio sequence tag selection algorithm achieves better or comparable accuracy to other approaches. Database search results show that the sequence tags of lengths 3 and 4 filter out more than 98.3% and 99.8% peptides respectively when applied to a yeast peptide database. With the dramatically reduced search space, the point process model achieves significant improvement in accuracy as well. Availability: The software is available upon request. Contact: {chunmei,cai}@cs.uga.edu

• The IPDG finite element discretizations are developed for the mildly nonlinear second-order elliptic partial differential equations and the corresponding well-posedness is established. • Some priori error estimates for discrete solution in the broken H 1 -norm, L 2 -norm and L ∞ -norm are separately derived. • A two-grid method is designed for solving the IPDG discretization scheme and the corresponding error estimate is provided. Two-grid interior penalty discontinuous Galerkin (IPDG) method for the mildly nonlinear second-order elliptic partial differential equations is studied in this paper. The IPDG finite element discretizations are developed and the corresponding well-posedness is established by introducing the equivalent weak formulation of IPDG method and combining Brouwer's fixed point theorem. Some priori error estimates for discrete solution in the broken H 1 -norm, L 2 -norm and L ∞ -norm are derived, respectively. Two-grid method is designed for solving IPDG discretization scheme and the corresponding error estimate is provided. Numerical experiments are also shown to confirm the efficiency of the proposed approach. [ABSTRACT FROM AUTHOR]