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β-Cyclodextrin (β-CD) with a cage-like supramolecular structure possesses the hydrophobic internal ring and external hydroxyl groups, which are beneficial for intramolecular interactions known as "host-guest" chemistry. This study presents a β-CD-based three-functions-in-one and host-guest fire retardant (βCD-MOF@Schiff base), which incorporates self-crosslinking Schiff base into its cavity and modification of its surface by metal-organic framework (MOF). With the presence of 5 wt% of βCD-MOF@Schiff base, the LOI value of PLA composites increased to 29 % and showed 15 %, 17 % and 62 % reductions in peak heat release rate (pHRR), total heat release (THR), and the yield of hazard gas carbon monoxide, respectively. The mode action of FR on fire retardation of PLA showed that the FR promoted the char formation with higher thermal stability and graphitization, and modified the decomposition path of PLA. Additionally, the PLA composites exhibited enhanced UV resistance in the UVA and UVB areas with improved UV absorbance and the UPF values improving and doubling. This work develops a new approach to preparing biodegradable FR, which simultaneously endows fire safety and anti-UV properties for PLA. [Display omitted] [ABSTRACT FROM AUTHOR]

The research identified a hyaluronidase produced by Paenibacillus aquistagni SH-7-A, the highest hyaluronidase activity with 830 U/mL obtained under 24 h fermentation. Based on genomic analysis, a gene hysa1 encoding hyaluronidase hysA1 was mined. Hyaluronidase H1 was purified by ammonium sulfate precipitation, anion exchange chromatography, and gel permeation chromatography. The molecular weight of purified H1 was determined to be about 110 kDa by SDS-PAGE, and the sequence coverage of the protein search with hysA1 resulted in 77% by HPLC-MS/MS. Therefore, it was proven that hyaluronidase H1 was hysA1. The optimum temperature and pH for H1 activity were 40°C and pH 6, and it was stable at 30–40°C and pH 5–7, respectively. Ca2+, Mg2+, and Ni2+ enhanced the enzymatic activity, and it was strongly inhibited by Zn2+, Cu2+, EDTA, tween 80, Triton X-100, CTAB, DTT, and SDS. Using HA as a substrate, the K m and V max of H1 were found to be 0.1124 mg/mL and 0.0184 mol/min/mL, respectively. This is the first hyaluronidase production, purification, and characterization report from P.aquistagni. These characteristics showed that the hyaluronidase H1 would provide potential possibilities for commercial applications. • P. aquistagni SH-7-A was a strain with high hyaluronidase activity. • Whole-genome sequencing combined with mass spectrometry identified hyaluronidase H1. • Hyaluronidase H1 has excellent temperature stability and pH stability. [ABSTRACT FROM AUTHOR]

Powdered or granular manganese oxide has been used as a catalyst to promote the oxidation of dye in the presence of H2O2. However, the facile separation of manganese oxide from the treated water is still an open question. In order to accomplish a facile recovery, a simple two-step process, hydrolysis and oxidation-reduction, was adopted to immobilize in-situ generated amorphous manganese oxide on polymer fiber in this work. Due to the synergistic effect of manganese oxide and polymer matrix, along with the swelling response of fiber to water stimulus, the obtained catalyst was found to have higher catalytic activity for dye oxidation than single manganese oxide or fiber. When 0.072 g of catalyst and 0.05 mL of H2O2 were added in 10 mL of aqueous solution of cation blue with the concentration of 20 mg/L, the catalyst could be repeatedly used up to 10 cycles without any significant loss in its catalytic activity. The time that was needed for removing 90% of cation blue from its solution was less than 6 min during each cycle, and the removal efficiency of cation blue obtained at 10 min was up to 95%. The catalyst could accelerate the transformation of H2O2 into oxidative species such as HO∙, HOO∙, O2∙− and 1O2 in the presence of H2O, and the strong oxidizability of the oxidative species resulted in the rapid removal of cation blue. [ABSTRACT FROM AUTHOR]

This study presents an induction heating-based reactor for on-board methanol steam reforming for hydrogen production reactors and distributed hydrogen refueling stations, with the goal of developing a hydrogen production process with zero carbon emissions. The numerical results showed that the enhanced hydrogen production performance and temperature cold spots could be eliminated, and the methanol conversion was close to 100%. at 150 A and 20 kHz. Induction heating may significantly shorten the reactor's cold start-up time. Under 50 kHz, the temperature of the reactor wall can reach more than 500 K in 50 s, in other words, induction heating overcomes the problems of slowly heating/cooling rate for on-board methanol steam reforming for hydrogen generation reactors. Overall, this study supports the feasibility of producing green hydrogen with zero carbon emissions for advancing the development of an environmental hydrogen economy and the cold start-up of distributed hydrogen energy and vehicle-used hydrogen production equipment. • Green methanol reforming via induction heating has the potential to produce zero carbon emissions. • The reactor allows for fast a cold start and a simpler structure. • Induction heating allows for precise temperature control and near-complete methanol conversion. • Coupled calculations for catalytic reforming reaction and induction heating. [ABSTRACT FROM AUTHOR]

In this paper, a novel active power filter (APF), which utilizes a highly reliable and efficient dual-buck inversion topology, is designed and integrated to a more electric aircraft (MEA) power grid to eliminate harmonics, correct power factor of supplies, and minimize the effect of unbalanced loads. The harmonic cancellation method, which provides a three-phase reference current in phase with the positive sequence of fundamental voltage, and the hysteretic current control method are adopted to control the proposed APF. After the parameters are carefully designed, which is swiftly followed by operational principle analysis, the proposed APF is integrated into a 125-kVA frequency-wild (360–800 Hz) hybrid high-voltage alternating current/high-voltage direct current MEA power grid. System-level simulations are carried out within the whole flight phases, with and without the proposed APF. The results show that the system harmonics and power factor can be strictly limited within the requirements of the most recent military aircraft electrical standard MIL-STD-704F with the proposed APF. [ABSTRACT FROM AUTHOR]

The isothermal crystallization behavior of a 1:1 poly( l -lactide)/poly( d -lactide) (PLLA/PDLA) mixture under pulsed shear was investigated by in-situ polarized light optical microscopy (POM) and wide angle X-ray scattering (WAXS). The effects of shear rate and temperature were studied. The results showed that application of shear flow increased the nucleation density, crystallization rate and degree of orientation for both stereocomplex crystals (SC) and α crystals. Interestingly, when the crystallization temperature was below the melting temperature of α crystals, the phase content of SC increased with shear rate, while the α content displayed a bell-shaped curve with regard to shear rate. The structure formation in this system was closely related to the shear-induced nucleation, phase mixing and chain mobility. [ABSTRACT FROM AUTHOR]

An aryl amide derivative (TMB-5) was used to nucleate the poly( l -lactide)/poly( d -lactide) (PLLA/PDLA) blend for the first time. The effect of TMB-5 nucleating agent on the crystallization behavior of PLLA/PDLA blend was systematically investigated. The selective nucleation of stereocomplex (sc) crystals by incorporation of TMB-5 was realized under appropriate crystallization conditions. During the cooling process, various morphology of TMB-5 due to its partial or complete dissolution in the PLLA/PDLA blend melt was observed. Furthermore, an sc crystals layer on the lateral surface of TMB-5 was found. Upon cooling a PLLA/PDLA blend from 260 °C at rates between 2 and 100 °C/min, 0.5 wt% addition of TMB-5 induced a single melting peak of sc crystals and no homocrystallization was observed in the subsequent DSC heating scan. The melting temperature of the sc crystals was found to decrease in the presence of TMB-5 from 230 to ca. 200 °C, which is still 20 °C higher than that of PLLA homopolymer. The results suggest that the supramolecular structure of the nucleating agent plays an important role in the crystallization of the PLLA/PDLA blend. The difference in solubility and recrystallization ability of TMB-5 in polymer melt results in the variation of crystallization behavior of PLLA/PDLA blend, which is correlated with the concentration of TMB-5 and crystallization conditions including the final melting temperature, annealing time and cooling rate. [ABSTRACT FROM AUTHOR]

The hybrid system comprised by a proton exchange membrane (PEM) fuel cell and internal combustion engine shows many advantages for vehicle applications. The hybrid system can recover the un-reacted hydrogen from fuel cell, utilize heat in the combustion product from cylinder, or combine the advantages of both. Based on thermodynamics and electrochemistry, an indirect integration system of the PEM fuel cell and Otto cycle is established for vehicle applications. The irreversibilities such as the entropy production and overpotentials in the fuel cell, the finite-rate heat transfer between the air in the Otto cycle and combustion chamber wall, the irreversible compression, expansion, and regeneration processes in the Otto cycle are considered. The excellence of the PEM fuel cell compared with internal combustion engine is shown in terms of energy conversion efficiency. When the vehicle is speeding or launching suddenly, not only the flow rate of natural gas into the hybrid system should be increased but also a specific coupling mode between two powertrain systems should be found. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The non-isothermal crystallization behavior of poly( l -lactide)/poly( d -lactide) (PLLA/PDLA) blends under shear was investigated by in-situ polarized light optical microscopy (POM) and wide angle X-ray scattering (WAXS). Pulse shear for 5 seconds was applied to the melt during cooling. The effects of shear temperature and shear rate were systematically studied. It was found that the shear field could increase the nucleation density of stereocomplex crystal (SC), and accelerate the overall crystallization rate. The final crystallinity of SC increased to as high as ∼45% with a shear rate of 178 s −1 when the shear temperature was 150 °C. The onset crystallization temperature of α crystals increased by ∼10 °C. The final content of α crystals reduced with the increase of SC content. Multiple factors influence the crystallization of SC and α crystals, including the shear rate, shear temperature and the nucleating/confinement effect of SC on α crystals. [ABSTRACT FROM AUTHOR]

A novel model of the molten carbonate fuel cell (MCFC) and gas turbine (GT) hybrid system with direct internal reforming is established, where the fuel cell and the auxiliary burner are taken as the heat reservoirs of the GT. Expressions for the power output and efficiency of the hybrid system are derived by considering various irreversible losses resulting from the overpotentials in the MCFC, the heat leakage in the auxiliary burner, and the finite-rate heat transfer and compression, expansion, and regeneration processes in the GT. The effects of some key parameters including the molar fraction of the oxygen in the oxidant, the utilization factor of the hydrogen in the MCFC on the performance of the hybrid system are revealed. It is found that the efficiency of the hybrid system will be increased by adding the utilization factor of the hydrogen, and the maximum power output of the hybrid system will be achieved when the utilization factor of the hydrogen is equal to 0.78. Moreover, the flowing rates of the syngas and oxidant and the molar fraction of the oxygen in the oxidant are determined under the optimal efficiency or maximum power output of the hybrid system. [ABSTRACT FROM AUTHOR]

This work examined the effect of nucleating agents on the strain-induced crystallization of poly( l -lactide) (PLLA). Talc and poly( d -lactide) (PDLA) were used as the nucleating agents of PLLA. Wide angle X-ray scattering (WAXS) revealed that the original injection molded specimens of nucleated PLLA blends were free of PLLA α crystal. The structural evolution during uniaxial stretching of neat and nucleated PLLA above the glass transition temperature was investigated by in-situ WAXS. It was observed that the nucleating agents significantly accelerated the crystallization of PLLA during stretching. The accelerating effect for the PLLA crystallization during stretching increased in the following order: PDLA/talc > PDLA > talc. In step-strain measurements with a high stretching speed, the effect of nucleating agents on the crystallization of PLLA showed a strain-dependence. The enhancement of crystallization by nucleating agents was remarkable at 200% strain. However, with 500% strain, the strain-induced crystallization was dominant and the effect of nucleating agents on crystallization of PLLA was not obvious. The results were analyzed considering the nucleating effect of nucleating agents on PLLA. [ABSTRACT FROM AUTHOR]

Abstract: On the basis of the models of various developed high-temperature fuel-cell heat-engine hybrid systems, a unified model of hybrid systems is proposed. General expressions for the power output and efficiency of hybrid systems, high-temperature fuel cells such as solid oxide fuel cells (SOFCs) and molten carbonate fuel cells (MCFCs), and heat engines including the Brayton, Otto, Diesel, Atkinson, Braysson, and Carnot engines are, respectively, derived by using the theories of electrochemistry and non-equilibrium thermodynamics. The effects of main irreversible losses existing in real fuel cells and heat engines on the performance of hybrid systems are investigated. The general performance characteristics and optimal operating regions of some of the key parameters of hybrid systems are discussed in detail. A variety of special typical cases are discussed. The important results in the literature can be readily reproduced, and the interesting findings of our study are presented. [Copyright &y& Elsevier]

A textile dyeing technique based on structural colors has attracted increasing attention due to the advantages of being fadeless, free of photobleaching, and less pollution. Here, we reported a general method of fabricating vivid iridescent structural colors and photonic crystal (PC) patterns on various textiles by spray coating poly(St-MMA-AA) colloids. With water-repelling and plasma treatments, versatile textiles can be dyed by photonic crystal colorants and exhibit brilliant iridescent structural colors. The results showed that the surface wettability, assembly temperature, particle concentration, spraying distance, and spraying time were important factors in fabricating high-quality PCs on textiles. Due to the soft shell of the colloids with abundant COOH groups, as-prepared structural-colored fabrics presented a flexible and tough character. 1. Fabricating vivid iridescent structural colors and PC patterns on various textiles by spray coating poly(St-MMA-AA) colloids. 2. Combining fluorosilane functionalization and plasma to create a modified surface for self-assembling long-range ordered PCs on textiles. 3. The structural-colored fabrics present a flexible character due to the soft shell of the colloids with abundant COOH groups, 4. The spray-coated fabrics display varied iridescence colors at different viewing angles. [ABSTRACT FROM AUTHOR]

Abstract: The structural evolution during uniaxial tensile deformation of isotactic polypropylene (iPP) and its blend with olefin block copolymer (OBC) was comparatively investigated by in-situ synchrotron X-ray scattering. Small angle X-ray scattering showed that cavitation in iPP/OBC blend took place at a smaller strain than that in neat iPP. The reorientation of the cavities in iPP/OBC occurred at a lower strain than that in iPP as well. Wide angle X-ray scattering was applied to study the crystal-mesophase transition and the orientation process. Compared to the sharp transition in neat iPP, the mesophase formation and orientation in iPP/OBC blend proceeded gradually. The mesophase content and degree of orientation of iPP matrix in iPP/OBC blend were much lower than that in neat iPP within the investigated strain range. By the combination of scattering results and morphological observations, a deformation mechanism based on strain distribution and fracture mechanics was proposed. [Copyright &y& Elsevier]

Abstract: A new model of micro-/nanoscaled heat engines consisting of two thin long tubes with the same length but different sizes of cross section, which are filled up with ideal quantum gases and operated between two heat reservoirs, is put forward. The working fluid of the heat engine cycle goes through four processes, which include two isothermal processes and two isobaric processes with constant longitudinal pressure. General expressions for the power output and efficiency of the cycle are derived, based on the thermodynamic properties of confined ideal quantum gases. The influence of the size effect on the power output and efficiency is discussed. The differences between the heat engines working with the ideal Bose gas and Fermi gas are revealed. The performance of the heat engines operating at weak gas degeneracy and high temperatures is further analyzed. The results obtained are more general and significant than those in the current literature. [Copyright &y& Elsevier]

Abstract: In this study, a new molten carbonate fuel cell-gas turbine hybrid system, which consists of a fuel cell, three heat exchangers, a compressor, and a turbine, is established. The multiple irreversible losses existing in real hybrid systems are taken into account by the models of a molten carbonate fuel cell and an open Brayton cycle with a regenerative process. Expressions for the power outputs and efficiencies of the subsystems and hybrid system are derived. The maximum power output and efficiency of the hybrid system are numerically calculated. It is found that compared with a single molten carbonate fuel cell, both the power output and efficiency of the hybrid system are greatly enhanced. The general performance characteristics of the hybrid system are evaluated and the optimal criteria of the main performance parameters are determined. The effects of key irreversibilities on the performance of the hybrid system are investigated in detail. It is found that the use of a regenerator in the gas turbine can availably improve the power output and efficiency of the system. The results obtained here are significant and may be directly used to discuss the optimal performance of the hybrid system in special cases. [Copyright &y& Elsevier]

Abstract: Two kinds of low molecular weight aliphatic amides, N, N′-ethylenebis (12-hydroxystearamide) (EBH) and N, N′-ethylenebisstearamide (EBSA), have been selected in present study to mediate the crystallization behavior of poly (L-lactic acid) (PLLA). The results showed that the crystallization rate of PLLA was significantly improved with the addition of EBH and EBSA, and EBH presented a stronger nucleating efficiency. The correlation between the variation of chain conformation during the early stages of isothermal crystallization and the enhancement of crystallization rate for pure PLLA and its mixtures was investigated by time-resolved FTIR. The formation of interchain conformational-ordered structure and intrachain 103 helix structure for amide-doped PLLA preceded that for pure PLLA, suggesting a stimulatory nucleating effect of EBH and EBSA. In the case of PLLA/EBH, the interchain interactions of –(COC + CH3) and –CH3 groups were faster than the –(CH3+CC) intrachain interactions, while the interchain interactions and the intrachain 103 helix formation were nearly synchronous for PLLA/EBSA. The hydrogen bond interaction between hydroxyl groups in EBH and the carbonyl groups in PLLA was proposed to be an important factor influencing the conformation variation during isothermal crystallization of PLLA. [Copyright &y& Elsevier]

Abstract: Cavitation and superstructure evolution of polymers during stretching play crucial roles to influence the mechanical properties of materials. In this study, we investigated deformation-mediated superstructures and cavitation of poly (l-lactide) (PLA) as well as their dependence on stretching temperatures by in-situ small-angle X-ray (SAXS) analysis coupled with mechanical testing. It is found that the cavitation and crystalline deformation are strongly influenced by stretching stress during deformation, which significantly depends on the stretching temperature. At lower stretching temperature (70 °C), the cavitation is initiated before the yielding and then stimulates the crystallite shearing. At higher stretching temperature (90 °C), however, the crystallites shear firstly and then crystalline deformation promotes the formation of cavities orientated along the stretching direction. High stretching temperature benefits the formation of relatively perfect crystals with high orientation. The results provide the basic knowledge of how to adjust the mechanical properties of polymer materials by controlling their superstructure in the deformation process. [Copyright &y& Elsevier]

Abstract: A generic model of the hybrid system consisting of an alkaline fuel cell (AFC) and a heat-driven cycle, which may work as either a refrigerator or a heat pump, is originally established. On the basis of the models of AFCs and three-heat-reservoir cycles, the equivalent power output and efficiency of the hybrid system are obtained. The performance characteristic curves of the hybrid system are represented through numerical calculation. The maximum equivalent power output and efficiency of the hybrid system are determined. Problems concerning the optimal operation of the hybrid system are discussed. The effects of the main irreversible losses on the performance of the hybrid system are investigated in detail. It is important to note that the waste heat produced in the AFC can be readily used in such a hybrid cycle. [Copyright &y& Elsevier]

Abstract: Based on the current models of the solid oxide fuel cell and gas turbine, a generic model of a solid oxide fuel cell-gas turbine hybrid system is established, in which the multiple irreversibilities existing in real hybrid systems are taken into account. Expressions for the efficiencies and power outputs of both the subsystems and the hybrid system are analytically derived. The general performance characteristics of the hybrid system are revealed and the optimum criteria of the main performance parameters are determined. The effects of some key irreversibilities existing in the fuel cell and gas turbine on the performance of the hybrid systems are discussed in detail. The results obtained may be directly used to discuss some special cases of the hybrid system. [Copyright &y& Elsevier]

Abstract: The present work explored the structure-property correlations for the biopolymer poly(l-lactic acid) (PLA) by studying deformation-mediated molecular orientation and crystallization. The structural and morphological variations of amorphous PLA under different strain rates were investigated. The result showed that strain rate significantly influences its strain-hardening behavior. The crystallinity and orientation as well as cavitation of deformed PLA increase with the increase of strain rates. The structure evolution has been divided into three potential stages: (i) at small strains (<100%), the crystallinity of PLA increases by orientation-induced crystallization; (ii) at intermediate strains (100%–160%), the crystallinity of deformed PLA slightly decreases due to the breakage of existing crystals under stress accompanying with newly formed voids and cavities; (iii) at high strains (>160%), the increasing number of oriented chains in the amorphous regions promotes the crystallization of PLA. Our study suggests that strain rate and stretching strain play important roles on modulating the crystallization and orientation of amorphous PLA. [Copyright &y& Elsevier]

Abstract: With the help of the current models of proton exchange membrane (PEM) fuel cells and three-heat-source refrigeration cycles, the general model of a PEM fuel cell/refrigeration cycle hybrid system is originally established, so that the waste heat produced in the PEM fuel cell may be availably utilized. Based on the theory of electrochemistry and non-equilibrium thermodynamics, expressions for the efficiency and power output of the PEM fuel cell, the coefficient of performance and cooling rate of the refrigeration cycle, and the equivalent efficiency and power output of the hybrid system are derived. The curves of the equivalent efficiency and power output of the hybrid system varying with the electric current density and the equivalent power output versus efficiency curves are represented through numerical calculation. The general performance characteristics of the hybrid system are discussed. The optimal operation regions of some parameters in the hybrid system are determined. The advantages of the hybrid system are revealed. [Copyright &y& Elsevier]

Abstract: Based on the irreversible model of a PEM fuel cell working at steady state, expressions for the power output, efficiency and entropy production rate of the PEM fuel cell are analytically derived by using the theory of electrochemistry and non-equilibrium thermodynamics. The effects of multi-irreversibilities resulting from electrochemical reaction, heat transfer and electrical resistance on the key parameters of the PEM fuel cell are analyzed. The curves of the power output, efficiency and entropy production rate of the PEM fuel cell varying with the electric current density are represented through numerical calculation. The general performance characteristics of the PEM fuel cell are revealed and the optimum criteria of the main performance parameters are determined. Moreover, the optimal matching condition of the load resistance is obtained from the relations between the load resistance and the power output and efficiency. The effects of the leakage resistance on the performance of the PEM fuel cell are expounded and the optimally operating states of the PEM fuel cell are further discussed. [ABSTRACT FROM AUTHOR]

Abstract: A layerwise B k , k −1-spline finite strip method is developed for stress and failure analysis in fibre reinforced composite laminates. The composite laminates are divided into a number of numerical layers in the thickness direction. A linear variation of in-plane displacements are assumed across the thickness of each numerical layer to represent the sectional warping which can have significant effects on through thickness shear stresses. The development of B k , k −1-spline finite strip method is presented. Material failure criteria and material degradation models for progressive failure are discussed and integrated in a progressive failure analysis for composite laminates. Numerical applications include a progressive failure analysis example are presented to verify the layerwise B-spline finite strip method developed for stress and failure analysis in composite laminates. Whenever possible the present predictions are compared with the existing analytical and numerical results. [Copyright &y& Elsevier]

This paper describes an oral English course for non-English majors at a university in the People's Republic of China. In the first year of the course, the students were very resistant to participating in group-based speaking activities, and their end-of-year results were disappointing. In the second year, the teacher decided to involve the students actively in designing their course and planning activities which would meet their needs and reasons for wanting to speak English. The aim was to increase their motivation and overcome reticence by getting them to talk about what and how they wanted to learn. It was expected that both their confidence and their ability to speak English would improve through more personal engagement with the course. The effectiveness of this approach was assessed using self-evaluation forms, classroom observations, and tests which showed significant progress in the students’ speaking. [ABSTRACT FROM PUBLISHER]

Abstract: Based on the current models of solid oxide fuel cells and two-heat-source heat engines consisting of two isothermal and two polytropic processes, a general model of a class of fuel cell/heat engine hybrid systems is established, in which multi-irreversibilities existing in real hybrid systems are taken into account. Expressions for the efficiency and power output of the hybrid systems are analytically derived from the model. The curves of the efficiency and power output of the hybrid systems varying with the current density and the efficiency versus power output curves are represented through numerical calculation. The general performance characteristics of the hybrid systems are revealed and the optimum criteria of the main performance parameters are determined. The effects of some key irreversibilities existing in the fuel cell, regenerator and two-heat-source heat engine on the performance of the hybrid systems are discussed in detail. The results obtained here are very general and may be directly used to derive the various interesting conclusions of the hybrid systems which are operated under different special cases. [Copyright &y& Elsevier]

Abstract: A new toughening agent, polypropylene/poly(ethylene-co-propylene) in-reactor alloy (EP-P), has been adopted to modify isotactic polypropylene (PP) in present study. Systematic investigation has been performed on the inter-compositional interaction, crystalline structure, and phase morphology of a series of PP/EP-P blends. It has been found that the PP component from EP-P is thoroughly miscible with neat PP and they together serve as the matrix of the PP/EP-P blends, while the ethylene–propylene random copolymers (EPR) act as the dispersed phase. The ethylene–propylene segmented copolymers (EPS), behaving as the compatibilizer between the EPR dispersed phase and PP matrix, strengthen mutual incorporation and effective diffusion of the amorphous PP segments and the EPR molecules. Based on the in-depth understanding of the crystalline structure and phase morphology, the correlation between morphological structure and mechanical properties has been established. The excellent impact toughness of PP/EP-P blends with higher EP-P content is mainly attributed to the small PP crystallites scattered in the blends and the well dispersed EP copolymer domains in PP matrix. [Copyright &y& Elsevier]

Abstract: The receptor-binding domain (RBD) on spike protein of severe acute respiratory syndrome-associated coronavirus (SARS-CoV) is the main region interacting with the viral receptor-ACE2 and is a useful target for induction of neutralizing antibodies against SARS-CoV infection. Here we generated two monoclonal antibodies (mAbs), targeting RBD, with marked virus neutralizing activity. The mAbs recognize a new conformational epitope which consists of several discontinuous peptides (aa. 343–367, 373–390 and 411–428) and is spatially located neighboring the receptor-binding motif (RPM) region of the RBD. Importantly, W423 and N424 residues are essential for mAb recognition and are highly conserved among 107 different strains of SARS, indicating that the residues are the most critical in the epitope which is a novel potential target for therapeutic mAbs. A human–mouse chimeric antibody, based upon the original murine mAb, was also constructed and shown to possess good neutralizing activity and high affinity. [Copyright &y& Elsevier]

Abstract: Syndiotactic polypropylene (sPP) fiber was prepared by melt spinning with the taken-up velocity of 200–700m/min, the conformation and crystallization of which were systematically investigated by a combination of Fourier transform infrared (FTIR) spectroscopy, wide-angle X-ray diffraction (WAXD) and differential scanning calorimetry (DSC). The results indicated that sPP fibers consist of form I crystal with helical conformation at the spinning velocity of 200–300m/min, and the crystallinity and orientation are improved with the increase of spinning velocity in this range. As the spinning velocity exceeds 300m/min, sPP fibers contain mainly mesophase with trans-planar conformation and the content of form I decreases correspondingly. The crystallization behavior of sPP fiber with spinning velocity is different from that of most other crystalline polymers, i.e., the theory of orientation-induced crystallization is not well conformed to. For sPP, form I comprising of helical conformation is thermodynamically stable, though extensional stress can lead to transition from helical to trans-planar conformation, which is not favorable for the crystallization of form I. [Copyright &y& Elsevier]

Abstract: Two kinds of TiO2/sulfonated polyaniline (SPAn) nanocomposite ultrathin films were fabricated by layer-by-layer (LBL) self-assembly technique on various solid surfaces. One was fabricated with self-doped sulfonated polyaniline (SD-SPAn) and TiO2 sol, and another was with externally (HCl)-doped sulfonated polyaniline (ED-SPAn) and TiCl4. The linear growth of both the LBL films was proved by UV–vis spectroscopy. The ordered multilayer films were subsequently characterized by atomic force microscopy, cyclic voltammetry, and photoelectrochemical measurement. Their structure, electrochemical and photoelectrochemical properties were comparatively investigated. The morphology of ED-SPAn/TiO2 LBL films is evener and smoother than that of SD-SPAn/TiO2 LBL films. Two kinds of LBL films have different electrochemical behaviours, and ED-SPAn/TiO2 LBL films show a stabler but slower photocurrent response than SD-SPAn/TiO2 LBL films. [Copyright &y& Elsevier]

Abstract: Regular structures in polymer melt play important roles during crystallization and subsequently influence performances of polymer materials. In the present work, differential scanning calorimetry (DSC) and variable temperature Fourier transform infrared spectroscopy (VT-FTIR) were used to characterize the variations of regular structures in melt of syndiotactic polypropylene (sPP) during heating. It was found that during heating, the structural transition in sPP melt undergoes four stages: (1) destruction of long regular structures; (2) formation of short regular structures; (3) transition from short regular structures to isotropic state; and (4) isotropic state. These regular structures in sPP melt have distinct memory effects on the crystallization behaviors. By using Flory''s RIS model, it was found that in final isotropic state, the most common conformers are ttgg and tttt, corresponding to helical and planar–zigzag conformations, respectively. These findings are helpful to deeply understand the essence of structures in sPP melt and microstructure variations during melting. [Copyright &y& Elsevier]

Abstract: Tetrasulfonated copper phthalocyanine (CuTsPc)-capped TiO2 nanoparticle ultrathin films were fabricated by a layer-by-layer (LBL) self-assembly technique. Alternating bilayer structures were formed by consecutive adsorption of CuTsPc-capped TiO2 nanoparticles with poly(diallyldimethylammonium chloride). Optical and electrical measurements were carried out to characterize the CuTsPc-capped TiO2 nanoparticle ultrathin films. Optical measurements revealed uniform deposition. The surface morphology of such bilayer films showed a granular morphology similar to other classes of LBL films. Electrical measurements revealed an abnormal phenomenon under white light illumination. Electrochemical and photoelectrochemical measurements on such a bilayer system were carried out to elucidate the electron transport processes and the photovoltaic effect. [Copyright &y& Elsevier]

Abstract: The crystallization morphologies and mechanical behaviors of iPP/sPP blends and the corresponding fibers were investigated in the present work. For all the investigated iPP/sPP blends, the starting crystallization temperature of sPP during cooling process was significantly increased with increasing iPP content. The iPP/sPP blends are strongly immiscible at the conventional melt processing temperatures, in consistence with the literature results. As isothermally crystallized at 130°C, sPP still keeps melt state, while iPP component is able to crystallize and the spherulites become imperfect accompanied by decreasing of the crystallite size as sPP content increases. The addition of sPP decreases the crystallinity of iPP/sPP blends and fibers. The storage modulus, E′, of the iPP/sPP blends is higher than that of sPP homopolymer in the temperature range from −90 to 100°C. The iPP/sPP fibers can be prepared favorably by melt-spinning. As sPP content exceeds 70%, the elastic recovery of the iPP/sPP fibers is approximately equal to that of sPP homopolymer fiber. The drawability of the as-spun fiber of iPP/sPP (50/50) is better than that of sPP fiber, which improves the fiber processing performance and enhances the mechanical properties of the final product. The drawn fiber of sPP presents good elastic behavior within the range of 50% deformation, whereas the elastic property of the iPP/sPP (50/50) fiber slightly decreases, but still much better than that of iPP fiber. [Copyright &y& Elsevier]

The supermolecular structures of iPP fiber/matrix composites as a function of crystallization temperature were studied by means of optical microscopy. The results show that, even though partial melting of the iPP fibers is in favor of initiating the β-iPP crystal growth, the interfacial morphology of iPP single-polymer composites induced by its own fiber depends strongly on the crystallization temperature. It was found that transcrystalline structures of negative radial βIII-iPP or banded βIV-iPP can be produced within the crystallization temperature range 105–137°C, while transcrystallization zone of pure negative radial αII-iPP crystals is observed at higher crystallization temperature, e.g. 141°C. On the other hand, the surrounding iPP spherulites grown from the bulk are composed of α-iPP in the whole crystallization temperature range. However, the optical character of the spherulites is controlled by the thermal condition. [Copyright &y& Elsevier]

The mammalian inner ear comprises the cochleovestibular labyrinth, derived from the ectodermal otic placode, and the encasing bony labyrinth of the temporal bone. Epithelial–mesenchymal interactions are thought to control inner ear development, but the modes and the molecules involved are largely unresolved. We show here that, during the precartilage and cartilage stages, Fgf9 is expressed in specific nonsensory domains of the otic epithelium and its receptors, Fgfr1(IIIc) and Fgfr2(IIIc), widely in the surrounding mesenchyme. To address the role of Fgf9 signaling, we analyzed the inner ears of mice homozygous for Fgf9 null alleles. Fgf9 inactivation leads to a hypoplastic vestibular component of the otic capsule and to the absence of the epithelial semicircular ducts. Reduced proliferation of the prechondrogenic mesenchyme was found to underlie capsular hypoplasticity. Semicircular duct development is blocked at the initial stages, since fusion plates do not form. Our results show that the mesenchyme directs fusion plate formation and they give direct evidence for the existence of reciprocal epithelial–mesenchymal interactions in the developing inner ear. In addition to the vestibule, in the cochlea, Fgf9 mutation caused defects in the interactions between the Reissner''s membrane and the mesenchymal cells, leading to a malformed scala vestibuli. Together, these data show that Fgf9 signaling is required for inner ear morphogenesis. [Copyright &y& Elsevier]

In order to achieve an efficient ballistic protection at a low weight, it is necessary to deeply explore the energy absorption mechanisms of ballistic fabric structures. In this paper, finite element (FE) yarn-level models of the designed three-dimensional (3D) angle-interlock (AI) woven fabrics and the laminated two-dimensional (2D) plain fabrics are established. The ballistic impact responses of fabric panels with and without the interlocking Z-warp yarns during the projectile penetration are evaluated in terms of their energy absorption, deformation, and stress distribution. The Z-warps in the 3D fabrics bind different layers of wefts together and provide the panel with structural support along through-the-thickness direction. The results show that the specific energy absorption (SEA) of 3D fabrics is up to 88.1% higher than that of the 2D fabrics. The 3D fabrics has a wider range of in-plane stress dispersion, which demonstrates its structural advantages in dispersing impact stress and getting more secondary yarns involved in energy absorption. However, there is a serious local stress concentration in 2D plain woven fabrics near the impact location. The absence of Z-warps between the layers of 2D laminated fabrics leads to a premature layer by layer failure. The findings are indicative for the future design of ballistic amors. [ABSTRACT FROM AUTHOR]

• A novel model of the self-supporting proton exchange membrane fuel cell is proposed. • The heats from the fuel cell and residuary hydrogen is reclaimed. • The effects of main irreversible losses are discussed in detail. • The maximum power densities and corresponding efficiencies are calculated. • The optimal selection criteria of several key parameters are provided. A new theoretical model of the thermally self-sustained proton exchange membrane fuel cell (PEMFC) is proposed, where syngas is preheated by the heat from the reaction in the fuel cell and water gas shift reactions, and the endothermic steam reforming process of methane is maintained by absorbing a part of the combustion heat of residuary hydrogen from the fuel cell. Based on some thermal equilibrium equations, the temperatures of syngas and combustion product in different stages are calculated, respectively. The power density and conversion efficiency of the PEMFC are derived. The influences of the molar flow rate of syngas, hydrogen utilization ratio, and working temperature of the fuel cell on the property of the PEMFC are discussed detailedly. In the rational range of the operating temperature, the maximum power densities and corresponding efficiencies are calculated, the optimum values of several key parameters at the maximum power densities are determined, and the optimal selection criteria of molar flow rate of syngas and other parameters are provided. [ABSTRACT FROM AUTHOR]

[Display omitted] • We present a simplified fluorescent microscopy-surface plasmon resonance (FM-SPR) system. • Real-time simultaneous observation and acquisition of fluorescent carbon dots labeled silk fibroin kinetic processes using FM-SPR system. • The fluorescence image changes fitted well with the SPR signal changes. • The linear detection range was 2.5 μg/mL–100 μg/mL, and the real lowest detection limit reached 0.5 μg/mL. • The association rate and dissociation rate of N-CDs to SF which were 2.65 × 10−5/s and 1.52 × 10 −5/s, respectively. The use of fluorescent carbon dots (CDs) as highly precise biolabeling probes has been widespread in the fields of live cell imaging and protein labeling due to their small size and excellent photoluminescence ability to accurately target specific molecules with surface chemical properties. However, there was a lack of research on the interaction between CDs and labeled molecules. In this work, we presented a novel investigation strategy, the fluorescence microscopy-surface plasmon resonance (FM-SPR) system, which combined the use of fluorescence microscopy and wavelength modulation surface plasmon resonance to study the interaction between CDs and labeled molecules in real-time. Using this system, simultaneously recorded the SPR signals and the fluorescence images on the surface of the FM-SPR sensor chip. We observed the dynamic curve and fluorescence images of the interaction between green emissive nitrogen-doped carbon dots (N-CDs) and silk fibroin (SF) in real-time. The kinetic parameters, the quantitative analysis, and the investigation of the binding could be achieved. The results showed a strong linear relationship between the change in SPR signals and the concentration of N-CDs, with a linear coefficient of 0.99913. The linear detection range was 2.5 μg/mL–100 μg/mL, and the real lowest detection limit reached 0.5 μg/mL. Additionally, the green fluorescence points in the imaging region on the FM-SPR sensor chip increased with the concentration of N-CDs, which was consistent with the change in SPR signals. Using this system we also acquired the association rate and dissociation rate of N-CDs to SF which were 2.65 × 10−5/s and 1.52 × 10−5/s, respectively. This demonstrated the effectiveness of our method in quantitatively analyzing SF labeled with N-CDs. [ABSTRACT FROM AUTHOR]

The preparation of alanine from waste polylactic acid (PLA) is not only an effective way to recycle waste plastics, but also of great significance to develop a green, clean and efficient amino acid production process. In this work, we studied the synthesis of alanine by amination of PLA with ammonia solution over different types of supported bimetallic catalysts without external hydrogen. It was found that the bimetallic catalyst consisting of Ru and a non-precious metal Co supported on TiO2 (Ru–Co/TiO2) was efficient for the reaction. The selectivity of alanine and turnover frequency (TOF) were 65.2% and 1.5 h−1, respectively. The synergistic effect existing between Ru and Co in the catalyst was crucial for the catalytic performance, and the content of precious metal Ru in the catalyst was lower. This was the first attempt to introduce a non-precious metal component into the catalyst for the amination of polylactic acid to alanine through thermocatalysis. [ABSTRACT FROM AUTHOR]

External chemical reactors for steam reforming and water gas shift reactions are needed for a proton exchange membrane (PEM) fuel cell system using syngas fuel. For the preheating of syngas and stable steam reforming reaction at 600 °C, residual hydrogen from a fuel cell and a certain amount of additional syngas are burned. The combustion temperature is calculated and the molar ratio of the syngas into burner and steam reformer is determined. Based on thermodynamics and electrochemistry, the electric power density and energy conversion efficiency of a PEM fuel cell based syngas are expressed. The effects of the temperature, the hydrogen utilization factor at the anode, and the molar ratio of the syngas into burner and steam reformer on the performance of a PEM fuel cell are discussed. To achieve the maximum power density or efficiency, the key parameters are determined. This manuscript presents the detailed operating process of a PEM fuel cell, the allocation of the syngas for combustion and electric generation, and the feasibility of a PEM fuel cell using syngas. [ABSTRACT FROM AUTHOR]

In this study, the genomic tools were used to characterize the probiotic and bactericidal potential of Lactiplantibacillus plantarum HY41. Firstly, the strain was found to carry two insertion sequences and prophage regions, and there was no CRISPR/Cas system by whole-genome sequencing. At the same time, functional genes related to probiotics such as encoding exopolysaccharides synthesize proteins, stress tolerance, flavor protease, and terpenoids were found in HY41. The putative bacteriocin biosynthetic cluster was identified using BAGEL4, and the bacteriocin HY41 was purified, it was discovered that Lactiplantibacillus plantarum HY41 harbored a silent gene cluster responsible for producing pediocin PA-1. Along with the pedABCD operon, this gene cluster also contained the gene encoding a toxin-antitoxin (TA) system, which acted as a defense mechanism against phage infection, and it was not found in other studies. Activation of the silent genes can produce novel and with multiple functions bacteriocin. The mode of action of bacteriocin was studied by scanning electron microscopy, and the results showed that bacteriocin HY41 caused cell death by disrupting the cell membrane of Listeria monocytogenes. The analysis of the genome of Lactiplantibacillus plantarum HY41 has confirmed its probiotic and bactericidal properties, demonstrating its potential for industrial probiotic applications. • Analyze the probiotic characteristics of Lactobacillus plantarum HY41 through whole-genome sequencing. • Determine whether the gene encoding Pedocin PA-1 is expressed through purification. • MBC and SEM determine the killing mode of bacteriocins against Listeria monocytogenes ATCC 19116. [ABSTRACT FROM AUTHOR]

A sense of resource availability creates a scarcity mindset, leading people to behave in a more competitive way instead of in a collaborative way. This study aims to examine the relationship between scarcity mindset and cooperative behaviors among parents and offspring, and to explore whether parents' scarcity mindset is related to their offspring's scarcity mindset and cooperative behaviors. We collected 239 parent–offspring pairs from several universities in northwest China. They completed the scarcity mindset scale and a one‐shot public good game (PGG). A path model analysis was conducted to examine the relationship between scarcity mindset and cooperative behaviors for offspring and their parents, respectively. The relationship between parental scarcity mindset and offspring's cooperative behaviors was also examined. The results showed that there was a high correlation of scarcity mindset between parents and their offspring. Scarcity mindset was negatively related to cooperative behaviors among both parents and offspring. In addition, both parents' cooperative behaviors and offspring's scarcity mindset mediated the relationship between the parental scarcity mindset and offspring's cooperative behaviors. Our results supported the idea that scarcity mindset triggers competitive rather than cooperative orientation. The present findings reveal an intergenerational relationship between scarcity mindset and cooperative behaviors by highlighting the impacts of parental scarcity mindset on that of their offspring's and its additional effects on offspring's cooperative behaviors. [ABSTRACT FROM AUTHOR]

In this study, Debaryomyces hansenii Y-3 with good freeze–thaw tolerance and Saccharomyces cerevisiae H-1 with strong fermentation ability were used to obtain a mixed starter culture (MSC), which can be used for frozen dough production. Angel yeast A-1 and a single-strain S. cerevisiae H-1 were used as references. Sensory evaluation and electronic nose combined with headspace solid-phase micro-extraction gas chromatography–mass spectrometry (HS–SPME–GC–MS) were used to analyze the taste and flavor of fermented steamed bread samples. The results showed that more kinds of volatile flavor compounds were detected in steamed bread samples fermented by MSC than in the reference group. Among all frozen dough steamed bread samples, only MSC-fermented samples could detect compounds, such as 2-methyl-1-propanol, 3-methyl-1-butanol, 1-hexanol, and 1-pentanol. Moreover, the content of ethyl octanoate, phenethyl alcohol, and 3-methyl-1-butanol was the highest in this sample. Meanwhile, whole-genome sequencing analysis was performed on D. hansenii Y-3 and S. cerevisiae H-1. Based on KEGG pathway localization, four main pathways are involved in yeast freeze–thaw tolerance. Through genome comparison analysis, there were significant differences in the related coding genes involved in the synthesis of trehalose, glycerol, proline, and arginine that affect their freeze–thaw resistance in the genomes of the two yeast strains. Therefore, it can be speculated that these significant differences are the reason for their large differences in freeze–thaw resistance. [ABSTRACT FROM AUTHOR]

Aims and objectives: This study aimed to determine the effect of home‐based lower limb resistance training (LLRT) in patients with stable COPD. Background: Pulmonary rehabilitation (PR) in COPD patients has been substantially investigated, but the rehabilitation components differ among studies. Few works have focused on home‐based LLRT. Furthermore, few studies have assessed muscle strength and functional status by isokinetic/isometric extensor muscle peak torque (PT) and five‐repetition sit‐to‐stand test (FTSST), respectively. Design: A randomised controlled design was adopted. Methods: (i) The home‐based LLRT consisted of six sets of lower limb training cycles by self‐gravity resistance and Thera‐band resistance at 8–12RM, 20–30 min/session and 3 sessions/week for 12 weeks. (ii) The intervention group (n = 25) received routine PR guidance and home‐based LLRT, whereas the control group (n = 22) received routine PR guidance only. The muscle strengths, FTSST durations, 6‐min walking distances (6MWDs) and COPD assessment test results at enrolment and week 12 were compared. Results: Relative to the baseline findings, all the indexes of muscle strength (isometric extensor muscle PT, isometric extensor muscle PT to body weight ratio [PT/BW], isokinetic extensor muscle PT and isokinetic extensor muscle PT/BW) did not significantly change in the intervention group. Meanwhile, no significant intragroup difference was noted among the indexes of muscle strength (except for isometric extensor muscle PT) in the control group. The FTSST decrease was significant between and within groups. By contrast, the 6MWD significantly increased within both groups, but not between the groups. The COPD assessment tool score decreased significantly within the intervention group. Conclusions: Compared with routine PR guidance, home‐based LLRT can improve not only the muscle strength and exercise endurance but also the lower limb functional status. Relevance to clinical practice: Our developed home‐based LLRT intervention is simple, safe and feasible in stable COPD patients and could hence be promoted in clinical practice. [ABSTRACT FROM AUTHOR]

• Synergy between MCA and ADP simultaneously enhancing the fire retardancy and heat resistant of PLA. • PLA composites showed anti-dripping property and reached 33% in LOI. • The addition of MCA and ADP effectively inhibited the formation of HC crystals, promoted the formation of SC crystals, which increased the HDT and VST by 96.3 °C and 111.3 °C, respectively. Developing fire retarded and heat resistant Polylactic Acid (PLA) is a challenging task owing to its high flammability, melt-dripping and low heat distortion temperature. In this work, based on the synergy between aluminum diethyl hypophosphite (ADP) and melamine cyanurate (MCA), a promising intumescent PLA with enhanced fire retardancy and heat resistant properties was obtained. The results showed that the PLA/15ADP/15MCA sample passed the UL-94 V-0 rating with anti-dripping performance and reached 33% in LOI. Besides, simultaneous addition of MCA and ADP can effectively inhibit the formation of HC crystals, promote the formation of SC crystals (55.23%), improve the crystallization rate and thus, significantly improve the heat resistance PLLA/PDLA/MCA15/ADP15 sample. Its heat distortion temperature (HDT) can reach 209.8 °C, which increased by 96.3 °C. In perspective, this work opens a new window in simultaneously improve the fire retardancy and heat resistance of PLA, which can highly expand its application. [ABSTRACT FROM AUTHOR]

The interplay between crosslinks and crystals is critical for the mechanical properties and applications of Eucommia ulmoides gum (EUG). In this work, EUG samples with different crosslink densities are prepared by sulfur vulcanization. The effect of crosslink density on the crystallization, melting, and mechanical properties are systematically investigated. As expected, crosslinks suppress the crystallization of EUG, resulting in a decrease in melting/crystallization temperature, crystallinity, modulus, and yield stress. Interestingly, vulcanized EUG can gradually crystallize during annealing at room temperature, showing a nonequilibrated state and slow crystallization kinetics. Correspondingly, the modulus increases with the annealing time. Cyclic deformation tests show that EUG vulcanizates have a lower hysteresis loss in the first cycle but a much higher hysteresis loss for subsequent cycles, showing the potential to have low-frequency damping properties. In situ wide-angle X-ray diffraction demonstrates that the hysteresis loss of EUG depends significantly on strain-induced crystallization/melting. [ABSTRACT FROM AUTHOR]

Fibroblast growth factor (FGF) signaling mediates reciprocal mesenchymal-epithelial cell interactions in the developing mouse lung and limb. In the gastrointestinal (GI) tract, FGF10 is expressed in the cecal mesenchyme and signals to an epithelial splice form of FGF receptor (FGFR) 2 to regulate epithelial budding. Here, we identify FGF9 as a reciprocal epithelial-mesenchymal signal required for cecal morphogenesis. Fgf9 null (Fgf9-/-) mouse embryos have agenesis of the embryonic cecum, lacking both mesenchymal expansion and an epithelial bud. In the cecal region of Fgf9-/- embryos, mesenchymal expression of Fgf10 and Bmp4 is notably absent, whereas the expression of epithelial markers, such as sonic hedgehog, is not affected. Using epithelial and whole explant cultures, we show that FGF9 signals to mesenchymal FGFRs and that FGF10 signals to epithelial FGFRs. Taken together, these data show that an epithelial FGF9 signal is necessary for the expansion of cecal mesenchyme and the expression of mesenchymal genes that are required for epithelial budding. Thus, these data add to our understanding of FGF-mediated reciprocal epithelial-mesenchymal signaling. [ABSTRACT FROM AUTHOR]

A low molecular weight aliphatic amide, N, N′-ethylenebis (12-hydroxystearamide) (EBH), was selected to tailor the crystallization behavior of poly ( l-lactide) (PLLA). The effect of EBH on the crystallization kinetics, fine crystalline structure, and molecular mobility of PLLA has been systematically investigated. It has been found that the crystallizability of PLLA, including crystallization rate and crystallinity, can be promoted significantly by the addition of only 1 wt% EBH. Both the nucleation density and linear growth rate of spherulites have been improved, which together contributed to the decrease of overall crystallization time. The long period and lamellar thickness of PLLA crystals increased gradually with the isothermal crystallization temperature, whereas they were less influenced by the incorporation of EBH. Dynamic mechanical analysis proved that the mobility of PLLA chains was also increased in the presence of EBH. The accelerating effect of EBH on both the nucleation and molecular mobility of PLLA was supposed to be the hydrogen-bonding interaction between the hydroxyl groups in EBH and carboxyl groups in PLLA. [ABSTRACT FROM AUTHOR]

The function and pathological significance of circular RNAs (circRNAs) in autoimmune diseases, such as rheumatoid arthritis (RA), are barely known. Here, we explored the role of circ_0088036 in RA progression and its associated mechanism. The synovial lining layer tissues of RA patients and non-RA control patients were collected for clinical study in vivo, and tumour necrosis factor α (TNF-α)-induced RA-fibroblast-like synoviocytes (RA-FLSs) were used for the experiments in vitro. Cell proliferation was assessed by Cell Counting Kit 8 (CCK8) assay and flow cytometry. Cell apoptosis was analyzed by flow cytometry. Enzyme-linked immunosorbent assay (ELISA) was conducted to analyze the release of pro-inflammatory cytokines. Dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay were performed to verify the target interaction between microRNA-326 (miR-326) and circ_0088036 or frizzled class receptor 4 (FZD4). Circ_0088036 expression was elevated in the synovial lining layer tissues of RA patients and TNF-α-treated RA-FLSs. Circ_0088036 interference largely reversed TNF-α-induced proliferation and inflammation in RA-FLSs. The interaction between circ_0088036 and miR-326 was verified, and miR-326 silencing largely reversed circ_0088036 knockdown-mediated effects in TNF-α-treated RA-FLSs. MiR-326 bound to the 3' untranslated region (3'UTR) of FZD4 in RA-FLSs. FZD4 overexpression largely diminished miR-326 accumulation-mediated influences in TNF-α-treated RA-FLSs. Circ_0088036 could up-regulate FZD4 by sponging miR-326 in RA-FLSs. Circ_0088036 contributed to TNF-α-induced RA progression partly by targeting miR-326/FZD4 signalling. [ABSTRACT FROM AUTHOR]

Multiblock copolymers consistingof crystalline poly(butylene succinate)and amorphous poly(1,2-propylene succinate) (PBS-co-PPS) are synthesized. The microstructure of the materials is investigatedby the combination of thermal analysis and wide-angle/small-angleX-ray scattering (WAXS/SAXS). The noncrystalline PPS blocks are foundto locate predominately in the amorphous phase between crystallinelamellae of PBS. By means of in situWAXS coupledwith optical-assisted strain measurement, the deformation processof PBS-co-PPS is studied. The stiffness and strengthof PBS-co-PPS decrease with increasing PPS fraction,while the strain recovery behavior of PBS-co-PPSis similar to PBS homopolymer. Transition from α crystal toβ crystal is observed for all the PBS-co-PPSsamples. The critical stress for α–β transitionof PBS-co-PPS is determined, which is found to beindependent of PPS blocks. The universal critical stress for crystaltransition is interpreted through a single-microfibril-stretchingmechanism. [ABSTRACT FROM AUTHOR]