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EP elements are important research objects in the ring theory. This paper mainly gives sufficient and necessary conditions for an element in a ring to be an EP element, partial isometry, and strongly EP element by using solutions of certain equations.

Against the background of China’s advocating ecological civilisation construction, an urgent task and a major challenge are to identify key places for ecological protection and restoration and then propose optimisation strategies for future land use, especially in the Pearl River Delta (PRD), one of the regions in China that has the highest urbanisation level. In this study, we find the key places by constructing ecological security patterns and proposing optimisation strategies for future land use by analysing land-use status. We also propose a source identification method based on the resistance distance principle. Results show that forty-six sources were mainly distributed in the mountainous areas surrounding PRD but were less distributed along both sides of the Pearl River estuary. The difference in the spatial distribution of sources is remarkable. Eighty-four corridors generally had spider-like shapes. In the central plain of PRD, corridors were relatively long and narrow. Ninety pinch points were concentrated on existing rivers. Three barriers were located in the corridors between adjacent sources. Two artificial corridors were proposed to be established, which can improve the ecological network connectivity. The method for extracting sources based on the resistance distance principle is proven to be advantageous for improving the integrity of source extraction results and making ecological security patterns more reasonable.

Biomass materials show great potential in replacing mineral carbon source to fabricate novel high-energy electrode materials. However, it is greatly challenging to prepare core-shell carbon hybrid materials with homogeneous dispersion and high tap density features from biomass since biomass-carbons often exhibit blocky structure. Herein, we facilely fabricate the core-shell microcubes of MnO@C (CCM, average size of ∼5 μm) composite with high tap density of 2.17 g cm−3 using natural agaric as raw materials through simple hydrothermal treatments and calcination process. And the formation mechanism of core-shell microcube structures is analysized by the phase separator theory. It is found that the high-tap-density CCM composite with the stable porous carbon shell (∼1 μm) greatly contributes to accommodate the volume change of MnO active material during lithiation/delithiation process and enable rapid electron/ion transport. As expected, the CCM electrode offers a superhigh volumetric capacity of 1628.7 mAh cm−3, the high reversible capacity (1147 mAh g−1 at 0.1 A g−1), outstanding rate performance (552 mAh g−1 at 2 A g−1) and cycling stability (802 mAh g−1 after 950 cycles at 1 A g−1). We believe that the facile and low-cost biomass-intervened strategy is feasible to fabricate practical core-shell structured metal oxide@carbon composites for efficient electrochemical energy storage.

The capacitive properties of asymmetric supercapacitors (ASCs) are inseparable from the development of anode and cathode materials, which usually required high accessible surface area and uniform p...

In this paper, we introduce a new class of EP elements which is called strongly EP element and give some characterizations of strongly EP elements

In-vivo optic nerve head (ONH) biomechanics characterization is emerging as a promising way to study eye physiology and pathology. We propose a high-accuracy and high-efficiency digital volume correlation (DVC) method to characterize the in-vivo ONH deformation from optical coherence tomography (OCT) volumes. Using a combination of synthetic tests and analysis of OCTs from monkey ONHs subjected to acutely elevated intraocular pressure, we demonstrate that our proposed methodology overcame several challenges for conventional DVC methods: First, a pre-registration technique was used to remove large ONH rigid body motion in OCT volumes which could lead to analysis failure; second, a modified 3D inverse-compositional Gaussian Newton method was used to ensure sub-voxel accuracy of displacement calculations despite high noise and low image contrast of some OCT volumes; third, a tricubic B-spline interpolation method was applied to improve computational efficiency; fourth, a confidence parameter was introduced to guide the searching path in the displacement calculation; fifth, a confidence-weighted strain calculation method was applied to further improve the accuracy. The proposed DVC method had displacement errors smaller than 0.037 and 0.028 voxels with Gaussian and speckle noises, respectively. The strain errors in the three directions were less than 0.0045 and 0.0018 with Gaussian and speckle noises, respectively. Compared with the conventional DVC method, the proposed method reduced the errors of displacement and strain calculations by up to 70% under large body motions, with 75% lower computation time, while saving about 30% memory. Our study demonstrates the potential of the proposed technique to investigate ONH biomechanics. STATEMENT OF SIGNIFICANCE: The biomechanics of the optic nerve head (ONH) in the posterior pole of the globe play a central role in eye physiology and pathology. The application of digital volume correlation (DVC) to the analysis of optical coherence tomography (OCT) images of the ONH has emerged as a promising way to quantify ONH biomechanics. Conventional DVC methods, however, face several important challenges when analyzing OCT images of the ONH. We introduce a high-accuracy and high-efficiency DVC method to characterize in vivo ONH deformations from OCT volumes. We demonstrate the new method using synthetic tests and actual OCT data from monkey ONHs. The new method also has the potential to be used to study other tissues, as OCT applications continue to expand.

Polylactide (PLA) is one of the most promising polymers that has been widely used for the repair of damaged tissues due to its biocompatibility and biodegradability. PLA composites with multiple properties, such as mechanical properties and osteogenesis, have been widely investigated. Herein, PLA/graphene oxide (GO)/parathyroid hormone (rhPTH(1-34)) nanofiber membranes were prepared using a solution electrospinning method. The tensile strength of the PLA/GO/rhPTH(1-34) membranes was 2.64 MPa, nearly 110% higher than that of a pure PLA sample (1.26 MPa). The biocompatibility and osteogenic differentiation test demonstrated that the addition of GO did not markedly affect the biocompatibility of PLA, and the alkaline phosphatase activity of PLA/GO/rhPTH(1-34) membranes was about 2.3-times that of PLA. These results imply that the PLA/GO/rhPTH(1-34) composite membrane may be a candidate material for bone tissue engineering.

Chirality is common in nature and plays the essential role in maintaining physiological process. Chiral inorganic nanomaterials with intense optical activity have attracted more attention due to amazing properties in recent years. Over the past decades, many efforts have been paid to the preparation and chirality origin of chiral nanomaterials; furthermore, emerging biological applications have been investigated widely. This review mainly summarizes recent advances in chiral nanomaterials. The top-down and bottom-up preparation methods and chirality origin of chiral nanomaterials are introduced; besides, the biological applications, such as sensing, therapy, and catalysis, will be introduced comprehensively. Finally, we also provide a perspective on the biomedical applications of chiral nanomaterials.

Lamina cribrosa (LC) deformations caused by elevated intraocular pressure (IOP) are believed to contribute to glaucomatous neuropathy and have therefore been extensively studied, in many conditions, from in vivo to ex vivo. We compare acute IOP-induced global and local LC deformations immediately before (premortem) and after (postmortem) sacrifice by exsanguination.The optic nerve heads of three healthy monkeys 12 to 15 years old were imaged with spectral-domain optical coherence tomography under controlled IOP premortem and postmortem. Volume scans were acquired at baseline IOP (8-10 mm Hg) and at 15, 30, and 40 mm Hg IOP. A digital volume correlation technique was used to determine the IOP-induced three-dimensional LC deformations (strains) in regions visible premortem and postmortem.Both conditions exhibited similar nonlinear relationships between IOP increases and LC deformations. Median effective and shear strains were, on average, over all eyes and pressures, smaller postmortem than premortem, by 14% and 11%, respectively (P's0.001). Locally, however, the differences in LC deformation between conditions were variable. Some regions were subjected premortem to triple the strains observed postmortem, and others suffered smaller deformations premortem than postmortem.Increasing IOP acutely caused nonlinear LC deformations with an overall smaller effect postmortem than premortem. Locally, deformations premortem and postmortem were sometimes substantially different. We suggest that the differences may be due to weakened mechanical support from the unpressurized central retinal vessels postmortem.Additional to the important premortem information, comparison with postmortem provides a unique context essential to understand the translational relevance of all postmortem biomechanics literature.

The diameter of fibers is a critical factor in determining their final applications. When the diameter of aramid fibers changes from microns to nanoscale, its range of applications will be greatly extended. In this short review, the preparation of aramid nanofibers (ANFs) with diameters from ten nanometers to more than one hundred nanometers is introduced. Due to their excellent mechanical properties and their chemical and thermal stability, ANFs have been widely used as novel nanomaterials and composited with other materials, mainly for use in reinforced composites, energy storage, filtration and adsorption, biomedicine and electromagnetic fields. In this short review, the application of ANFs and their composites during the last 10 years is concisely summarized and a brief perspective on ANFs and their composites is also presented.

In-vivo optic nerve head (ONH) biomechanics characterization is emerging as a promising way to study eye physiology and pathology. We propose a high-accuracy and high-efficiency digital volume correlation (DVC) method for the purpose of characterizing the in-vivo ONH deformation from volumes acquired by optical coherence tomography (OCT). Using a combination of synthetic tests and analysis of OCTs from monkey ONHs subjected to acute and chronically elevated intraocular pressure, we demonstrate that our proposed methodology overcomes several challenges for conventional DVC methods. First, it accounts for large ONH rigid body motion in the OCT volumes which could otherwise lead to analysis failure; second, sub-voxel-accuracy displacement can be guaranteed despite high noise and low image contrast of some OCT volumes; third, computational efficiency is greatly improved, such that the memory consumption of our method is substantially lower than with conventional methods; fourth, we introduce a parameter measuring displacements confidence. Test of image noise effects showed that the proposed DVC method had displacement errors smaller than 0.028 voxels with speckle noise and smaller than 0.037 voxels with Gaussian noise; The absolute (relative) strain errors in the three directions were lower than 0.0018 (4%) with speckle noise and than 0.0045 (8%) with Gaussian noise. Compared with conventional DVC methods, the proposed DVC method had substantially improved overall displacement and strain errors under large body motions (lower by up to 70%), with 75% lower computation times, while saving about 30% memory. The study thus demonstrates the potential of the proposed technique to investigate ONH biomechanics.

Carbon nanotubes (CNTs) have attracted great interest in biomedical fields. However, the potential toxicity and poor dispersion of CNTs have greatly limited its application. In this work, a mussel-inspired method combined with the “thiol-Michael” click reaction was used to modify the surface of CNT and improve its properties. Firstly, a CNT was treated with dopamine, and then alginate grafted with L-cysteine was anchored onto the surface of CNT via click reaction, which realized the long-time dispersion of CNT in water. Furthermore, the in vitro test also demonstrated that the alginate may improve the biocompatibility of CNT, and thus may broaden the application of CNT in the biomedical field.

We give some sufficient and necessary conditions for an element in a ring to be an EP element, partial isometry, normal EP element and strongly EP element by using solutions of certain equations.

A ring R is called a left weakly local commutative ring (WLC, for short) if for any a ∈ N (R) and b ∈ R, (ab)2 = ba2b, which is a proper generalization of CN rings. In this paper, we show that (1) ...

In this article, some characterizations of one-sided generalized inverses are investigated. Let R be a *-ring and a∈R. It is shown that for k≥2, a* is right (ak,a) invertible if and only if a∈a2R∩R...

We give some sufficient and necessary conditions for an element in a ring with involution to be a partial isometry by using certain equations admitting solutions in a definite set.

Bone-tissue engineering is an alternative treatment for bone defects with great potential in which scaffold is a critical factor to determine the effect of bone regeneration. Electrospun nanofibers are widely used as scaffolds in the biomedical field for their similarity with the structure of the extracellular matrix (ECM). Their unique characteristics are: larger surface areas, porosity and processability; these make them ideal candidates for bone-tissue engineering. This review briefly introduces bone-tissue engineering and summarizes the materials and methods for electrospining. More importantly, how to functionalize electrospun nanofibers to make them more conducive for bone regeneration is highlighted. Finally, the existing deficiencies of functionalized electrospun nanofibers for promoting osteogenesis are proposed. Such a summary can lay the foundation for the clinical practice of functionalized electrospun nanofibers.

The pythagorean fuzzy (PF) β-covering has been constructed to extend the fuzzy β-covering, and a type of reducts in pythagorean fuzzy (PF) β-coverings has been proposed based on the union operation. However, for svveral statements, there will be no reducts in PF β-coverings. Hence, this concept should be replenished by other concepts. Hence, we propose the new type of reducts in PF β-coverings in this paper, and we call it type-2 PF reduct. Moreover, the type-2 PF reducts in PF β-covering approximation spaces are studied while adding and removing several objects of the universe. First, the notion of the type-2 PF reduct in a PF β-covering approximation space is presented. Then, some properties of type-2 reducts of PF β-coverings are investigated while adding and removing some objects.

In this paper, we investigate the matrix representations of two types of optimistic multigranulation fuzzy covering rough set models. Firstly, some new matrices and matrix operations are presented. Then, matrix representations of multigranulation fuzzy measure degrees are proposed. Finally, matrix approaches are also used in two types of optimistic multigranulation fuzzy covering rough set models.

The purpose of this paper is to give some sufficient and necessary conditions for an element to be a strongly [Formula: see text] element through some transformations of equations.

Dopamine (DA) is an important catecholamine neurotransmitter in the mammalian central nervous system, and is involved in many behavioral responses and brain functions, and thus the detection of DA is much important. Chiral nanoparticles (NPs) have aroused much attention and showed many potential applications. In this work, Chiral ZnO NPs was prepared, and the nanoparticles can disperse well without aggregation. The Circular dichroism (CD) test showed strong chiroptical signals, demonstrating it is an effect method to prepare Chiral ZnO with cysteine as ligand. The photoluminescent properties of Chiral ZnO was investigated and showed quenching effect to dopamine, which make it possible to be used as probes to detect dopamine in biological samples with high selectivity and sensitivity.

We give some sufficient and necessary conditions for an element in a ring with involution to be normal by using solutions of certain equations.

An ideal separator of lithium-ion battery (LIB) should have a zero ionic resistance. Low ionic resistance (high ionic conductivity) will greatly help to realize very fast ion diffusion and superhigh rate capability of LIBs. The most effective technique to achieve low ionic resistance of separator is to reduce its thickness or increase its porosity. Paradoxically, the low thickness and high porosity will inevitably decrease the mechanical strength of separators. Inspired by the hierarchical structures of abalone shell, we demonstrate in this work an ultrathin silica-anchored layered (PVdF/PE/PVdF) porous fiber separator prepared via electrospinning. The separator displays both ultrathin thickness (∼20 μm thick) and high mechanical strength of ∼11.2 MPa, as well as high porosity, which results in high electrolyte uptake (∼380%) and ionic conductivity (∼2.5 mS cm–1). When such thin separator was deployed in a LiFePO4/Li cell, and the cell can deliver an initial discharge capacity of 134.3 mA h g–1 at a high ...

Purpose To determine if ocular ductions deform intrapapillary and peripapillary tissues in optic nerve head drusen (ONHD) and to compare these deformations with healthy eyes and eyes with other optic neuropathies. Design Observational case series. Participants Twenty patients with ONHD. Methods Axial rasters of the optic nerve from a spectral-domain OCT device (Cirrus 5000; Carl Zeiss Meditec, Inc, Dublin, CA) were used to analyze the shape of the peripapillary basement membrane (ppBM) layer in 20 confirmed cases of ONHD. We compared registered images obtained from 2 eye positions: 10° to 15° in adduction and 30° to 40° in abduction. Geometric morphometrics was used to analyze the shape of the ppBM layer defined by placing 10 equidistant landmarks extending 2500 μm on both sides of the basement membrane opening. We also adapted an image strain tracking technique to measure regional intrapapillary strains in 6 patients. Using manually placed nodes on the reference image (in adduction), an iterative, block-matching algorithm is used to determine local displacements between the reference and its paired image in abduction. Displacement vectors were used to calculate the mean shear and effective strain (percent change). Main Outcome Measures Peripapillary shape deformations, intrapapillary shear strains, and effective strains. Results We found a statistically significant difference in the shape of the ppBM layer between abduction and adduction ( P P P Conclusions This study demonstrates that horizontal ocular ductions induce significant shearing deformations of the peripapillary retina and prelaminar intrapapillary tissues. We also found that the deformations in healthy persons are similar in magnitude to ONHD. Based on these findings, we speculate that patients with intrapapillary calcifications exposed to the long-term effects of repetitive shearing (induced by ocular ductions) may contribute to the progressive axonal loss and vascular complications associated with ONHD.

Although cobalt sulfide is a promising electrode material for supercapacitors, its wide application is limited by relative poor electrochemical performance, low electrical conductivity, and inefficient nanostructure. Here, we demonstrated that the electrochemical activity of cobalt sulfide could be significantly improved by Al doping. We designed and fabricated hierarchical core-branch Al-doped cobalt sulfide nanosheets anchored on Ni nanotube arrays combined with carbon cloth (denoted as CC/H-Ni@Al-Co-S) as an excellent self-standing cathode for asymmetric supercapacitors (ASCs). The combination of structural and compositional advantages endows the CC/H-Ni@Al-Co-S electrode with superior electrochemical performance with high specific capacitance (1830 F g–1/2434 F g–1 at 5 mV s–1/1 A g–1) and excellent rate capability (57.2%/72.3% retention at 1000 mV s–1/100 A g–1). The corresponding all-solid-state ASCs with CC/H-Ni@Al-Co-S and multilayer graphene/CNT film as cathode and anode, respectively, achieve a ...

Let $R$ be a ring with involution $*$. An element $a\in R$ is called $*-$strongly regular if there exists a projection $p$ of $R$ such that $p\in comm^2(a)$, $ap=0$ and $a+p$ is invertible, and $R$ is said to be $*-$strongly regular if every element of $R$ is $*-$strongly regular. We discuss the relations among strongly regular rings, $*-$strongly regular rings, regular rings and $*-$regular rings. Also, we show that an element $a$ of a $*-$ring $R$ is $*-$strongly regular if and only if $a$ is $EP$. Hence we finally give some characterizations of $EP$ elements.

A ring R is called NEC if for any a, b ? N(R), ab = ba. The class of NEC rings is a proper generalization of the class of CN rings. First, with the aid of NEC rings, some characterizations of CN rings and reduced rings are given. Next we extend many properties of CN rings to NEC rings such as we show that NEC rings are directly finite and left min-abel; NEC regular ring are strongly regular; a ring R is NEC if and only if every Pierce stalk of R is NEC; Also we discuss some properties of NEC exchange rings; Finally, we give some properities of MP-invertible elements.

The aim of this paper is to describe the elements in rings with involution which are EP. Especially, contact is established between EP elements and the solutions of certain equations. In addition, we reduce the preliminary requirements met in some existing results.

Carbon nanofiber (CNF) composites could be promising materials for flexible supercapacitors. However, it is still a challenge to grow uniformly active materials on the surface of fibers and maintain flexibility. Herein, Co3O4 nanoparticle-decorated CNFs have been produced through the combination of electrospinning technology and a polydopamine-assisted self-assembly strategy. The free-standing hybrid electrode exhibited a high capacitance of 418 F g−1 at a current density of 0.5 A g−1 in 2 M KOH solution. In addition, the as-fabricated symmetric supercapacitors (SCs) presented excellent electrochemical performance with a capacitance of 55 F g−1, an energy density of 14.97 W h kg−1, and a power density of 5660 W kg−1. Notably, the symmetric SC device exhibited remarkable electrochemical stability and flexibility (93 % capacitance retention after 2000 cycles and 97 % after bending 100 times to 60°).

While various structures of NiCo2S4 are well investigated for supercapacitors, it is extremely challenging to achieve high capacitance of NiCo2S4 by engineering favorable architecture. Here, we have developed a pinecone-inspired supercapacitor electrode composed of vertically aligned NiCo2S4 nanosheet arrays supported on electrospun carbon nanofibers (CNFs) with polypyrrole (PPy) uniformly wrapped on each nanosheet surface to boost the pseudocapacitive performance. Taking advantages of the high capacitance of vertical NiCo2S4 nanosheets and the conductive wrapping of PPy, the hybrid electrode exhibits high specific capacitance (2961 F g−1 at 1 A g−1) with excellent cycling stability (99.85% capacitance retention after 5000 cycles). The asymmetric supercapacitor (ASC) fabricated using the CNFs/NiCo2S4@PPy nanosheet arrays as the positive electrode and CNFs/MoS2 nanosheets as the negative electrode demonstrates outstanding electrochemical performance for practical energy storage applications. The ASC shows excellent maximum energy density of 37.15 W h kg−1 at the power density of 598.80 W kg−1 in an aqueous electrolyte and 44.45 W h kg−1 at the power density of 698.60 W kg−1 in a quasi-solid state gel electrolyte with robust long-term cycling stability.

The efficient exploitation and utilization of low-cost and biomass-derived carbon materials will play an active role in developing sustainable energy storage systems. However, the difficult morphology control and incomplete activation limits their pervasive application in electrochemical energy storage. Inspired by the famous Chinese folk handicraft of sugar-figure blowing, biomass-derived carbon aerogels (GCA) with 2 D graphene-like thin nanosheets were fabricated by a simple chemical blowing strategy from a viscous agaric solution obtained through hydrothermal treatment of agaric. A chemical blowing agent (NH4 Cl) was used to effectively exfoliate the bulk biomass-derived carbon flake into 2 D graphene-like nanosheets, which resulted in a highly porous structure and high specific area (2200 m2 g-1 ) after the activation process. As a result, a high specific capacitance of 340 F g-1 at 3 A g-1 and a high specific energy of 25.5 Wh kg-1 at a power density of 2 kW kg-1 was obtained for the GCA electrode, which can be attributed to the abundant electrochemically active surfaces, short ion transport paths, and effective electrolyte infiltration.. This work demonstrates an effective and low-cost strategy to prepare hierarchical and well-organized porous biomass carbon materials with graphene-like nanosheets for high-performance supercapacitors.

We explore the existence of MP-inverse in rings with involution. In addition, we give some equivalent conditions for an element of a C * − algebra to be a weighted-EP element and weighted partial isometry.

Due to the deficiency of low melting point and poor wettability of commercial polyolefin separators, the design and development of ceramic coating separators have been received more and more attention in Li-ion batteries recently. However, it is challenging to solve the disadvantageous exfoliation issue of ceramic coating during charge/discharge cycles and needs to be addressed urgently. Herein, a covalent grafting interface engineering strategy has been proposed to prepare a highly efficient and stable polypropylene/mSiO2 separator (PP-g-mSiO2) by the nanoscale mSiO2 layer anchoring on the surface of PP separator with covalent bonding. As expected, the covalent bonding force increase the interfacial stability of PP-g-mSiO2 separator and the mSiO2 NPs facilitate more storage of electrolyte, which results in high thermal stability, high electrolyte affinity and swift lithium-ion diffusion. When used as the separator in LIBs, the Li/LiFePO4 cell with PP-g-mSiO2 separator exhibits excellent rate capability with a discharge capacity of 101 mA h/g at 5 C and remains high capacity retention of 93% after 1000 continuous charge–discharge cycles, which suggests that the PP-g-mSiO2 separator possesses a stable and covalent grafting ceramic surface and have greater affinity to electrolyte, resulting in quicker lithium-ion diffusion and excellent cycling stability. Therefore, the covalent grafting interface modification has confirmed an effective strategy to block exfoliation issues of ceramic coating and developed the high-performance ceramic separators for LIBs.

Few molecular studies have shown that the number of bacterial species in implant-associated infection may have been underestimated. To determine the actual microbial diversity in implant-associated infection, a high-throughput sequencing method was adopted to sequence the DNAs extracted from the tissues of infected and uninfected patients. Principal component analysis (PCA) and β diversity showed an obvious divergence of infected and uninfected groups, and that the overgrowth of Proteobacteria (80.87%), Firmicutes (13.41%) in the positive deep infection group (P.d, via biopsy) and Proteobacteria (91.68%) in the positive surface infection group (P.s, via swabs) might be the causative factors in implant-associated infection. Moreover, Venn results indicated that a mean of 330 common operational taxonomic units (OTUs) was obtained in all groups, of which 113, 109, 45, 20, 13 and 12 OTUs belonging to Proteobacteria, Actinobacteria, Acidobacteria, Planctomycetes, Gemmatimonadetes and Chloroflexi were identified. In conclusion, many traditional "pathogenic bacteria" were identified as the common bacteria in operation sites, and the disruption of their complex interaction caused infection; therefore, further work is need to illustrate the aetiology of implant-associated infection using in-depth systems-level analyses.

A critical challenge in the preparation of reinforced polymer nanocomposites is to prevent the aggregation of nanofillers. In this work, a novel poly(γ-benzyl-L-glutamate) (PBLG)-modified silicon dioxide@graphene oxide nanofiller (SiO2@GO-g-PBLG) was prepared via a continuous electrostatic complex and ring-opening polymerization (ROP) method. The grafted PBLG prevented the aggregation of SiO2 nanoparticles and GO sheets, realized the colloid stability of SiO2@GO-g-PBLG in organic solvents, and thus increased its phase interaction in a polymer matrix. The hybrid nanofiller greatly enhanced the mechanical properties of poly(L-lactide) (PLLA). As a typical feature, the tensile strength of PLLA nanocomposites with only 5 wt% of SiO2@GO-g-PBLG was 88.9 MPa, about 45% higher than that of pure PLLA. In addition, the hybrid nanofillers also have some positive effects on improving the thermal stability of PLLA. Therefore, SiO2@GO-g-PBLG was a promising hybrid nanofiller to reinforce polymers such as PLLA.

Lotus root imitated implant scaffolds with highly flexible drug release patterns were fabricated. Several critical release parameters could be conveniently prearranged through creating a precisely customized inner chamber via 3D printing. Furthermore, when postoperative infection caused hyperthermia, the inner drugs could be spontaneously released to inhibit the invasive pathogens.

A new family of three-arm polymer ionic liquids (PILs) with X counter anions [3P(MPBIm-X), X− = Br−, CF3SO3− (Tf−) and (CF3SO3)2N− (TFSI−)] were successfully synthesized. The effects of anion type on the chemical, thermal and ionic conductivity of PILs have been investigated. Results showed that 3P(MPBIm-X) with TFSI− counter anion (3P(MPBIm-TFSI)) possessed better thermal property and ionic conductivity. Furthermore, to obtain safe and flexible electrolytes with superior performance, solid-like composite electrolyte (SLCE) was fabricated by filling ion gel, the mixture of 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMIM-TFSI) incorporated into 3P(MPBIm-TFSI), in the micropores of PVDF-HFP electrospun membranes. It was found to be thermally stable up to 370 °C and electrochemically stable above 4.8 V. SLCE was nonflammable and showed negligible leakage property when subjected to load. At 50 °C, ionic conductivity of SLCE could reach 1 mS cm−1 (1.2 × 10−3 S cm−1), which is approximately two orders of magnitude higher than that of 3P(MPBIm-TFSI). Moreover, Li/SLCE/LiFePO4 solid-like state cells exhibited excellent reversible charge/discharge reactions and considerable capacity retention up to medium rates. Coulombic efficiency can remain 100% even after 100 cycles. Potential application of SLCE as an electrolyte for flexible lithium batteries was explored by scrutinizing the electrochemical performance of cells. Consequently, pouch cell exhibited stable cycling performance even in wrinkled configurations, without suffering from internal short-circuit failures between electrodes.

Novel pH-sensitive nanogels based on poly(ethylene glycol)-b-poly(L-glutamate-g-tyramine) (PEG-b-P(LGA-g-Tyr)) copolymer were developed for efficiently delivering and releasing proteins into HeLa cells. The core–shell nanogels were in situ fabricated through the enzyme-catalyzed oxidative coupling of tyramine moieties in the core of the self-assembled PEG-b-P(LGA-g-Tyr) micelles in the presence of horseradish peroxidase (HRP) and hydrogen peroxide (H2O2). The stable nanogels have spherical morphology with an average diameter of about 125 nm under physiological condition. The pH-dependent size shrink of the nanogels was observed by dynamic light scattering (DLS). Fluorescein isothiocyanate conjugate bovine serum albumin (FITC-BSA) was in situ incorporated into the nanogels with an entrapment efficiency of 69.9% during the enzyme-catalyzed crosslinking reaction. In vitro protein release profiles at pH 7.4 and pH 6.8 showed a burst effect followed by a continuous release phase. The FITC-BSA loaded nanogels exhibited pH-sensitive protein release. A significantly fast FITC-BSA release was observed at endosomal pH than at physiological pH. The cumulative release of FITC-BSA from the nanogels at pH 7.4 and pH 6.8 were 24.2% and 40.3%, respectively. Cell Counting Kit-8 (CCK-8) assay showed that these nanogels were non-toxic up to a concentration of 2.0 mg mL−1. Confocal laser scanning microscopy (CLSM) studies revealed that FITC-BSA loaded nanogels efficiently delivered and released proteins into HeLa cells. We are convinced that these enzymatically crosslinked nanogels with excellent biocompatibility and pH-responsibility have a promising potential for protein delivery system.

Atropisomerism becomes a popular structural feature in modern drug discovery. Using N-phenyl γ-lactam and phenyl-pyrazolone scaffolds, we showed that distinct 19F NMR peaks were present in atropisomers and dual signals emerged for covalently identical fluorine nuclei in hindered rotamers. Factors affecting 19F NMR chemical shifts in these molecules were discussed. We demonstrated that 19F NMR spectroscopy can be used to differentiate and detect atropisomers and rotamers in conformationally restricted molecules.

A type of reducts in intuitionistic fuzzy (IF) β-coverings has been presented based on the union operation. But for some problems, there is no reducts in IF β-coverings according to this definition. That is to say, this notion has its boundedness. Therefore, we present the new type of reducts in IF β-coverings in this paper, and we call it type-2 reduct. Moreover, the type-2 reducts in IF β-covering approximation spaces are investigated while adding and removing some objects of the universe. Firstly, the notion of the type-2 reduct in an IF β-covering approximation space is presented. Then, some properties of type-2 reducts of IF β-coverings are investigated while adding and removing some objects.

The lithium metal anode has extremely high theoretical specific capacity and most negative electrochemical potential. However, upon cycling, the formed dendrites result in severe safety concerns and poor stability, thus limiting the applications of the material. Herein, we report a novel separator with excellent lithiophilicity and strength obtained via in-situ modification of virgin cellulose paper (CP) with polydopamine (PDA) to effectively stabilize the Li metal anode. The as-obtained PDA-CP separator showed excellent thermal stability and high mechanical strength due to the interaction between PDA and cellulose molecule, and an excellent electrolyte affinity to enable high electrolyte uptake and ionic conductivity. More importantly, in symmetric Li/Li cells with the PDA-CP separator, the Li metal anode was stabilized during repeated stripping/plating processes over 500 cycles (3000 h) at a current density of 0.5 mA cm−2. Further, we achieved excellent cycling stability over 600 cycles at the rate of 5 C by employing Li/PDA-CP/LiFePO4 cells. The results demonstrate the immense potential of PDA-CP as advanced separator and propose an efficient and simple strategy to stabilize Li metal anode for the next-generation high-energy lithium-metal batteries.