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This paper describes the synthesis, characterization, and self-assembly behavior of amphiphilic polyethylene- block -poly( l -glutamate) (PE- b -PGA) diblock copolymers. PE- b -PGA diblock copolymers were obtained by ring-opening polymerization (ROP) of γ-benzyl- l -glutamate- N -carboxyanhydride (BLG-NCA) using PE–COOCH( i Pr)NH 2 as a macroinitiator and subsequent deprotection of the benzylester groups. The self-assembly behaviors of the PE- b -PGA copolymers in water were studied as a function of pH and ionic strength by means of fluorescence spectroscopy, laser light scattering, UV-circular dichroism, and transmission electron microscopy. The size of the polymeric micelles decreases with a decreasing pH value even at high salt concentrations because the solvating PGA units can perform a coil-to-helix transition. [ABSTRACT FROM AUTHOR]

Inhibiting thrombosis in extracorporeal dialyzer is predominantly determined by the compatible interface design. It is challenging to develop anticoagulant dialyzers for clinical heparin free dialysis. Herein, we develop an environmentally friendly approach to construct a hydrogel skin composed of poly (sodium alginate-acrylic acid) P (SA-AA) network on polysulfone (PSf) membranes via pre-seeding initiator into membrane matrix and subsequently crosslinking SA and AA in aqueous solution. Physicochemical properties of modified membranes with different SA/AA ratio were characterized by attenuated total reflectance fourier transform infrared spectra (ATR-FTIR) spectrum, proton nuclear magnetic resonance (13 C NMR), scanning electron microscopy (SEM) and atomic force microscope (AFM) and contact angle. Antifouling property was demonstrated by proteins adsorption and E. coli adhesion. Hemocompatibility was comprehensively evaluated by hemolysis ratio, anticoagulation activity (APTT and TT), complement activation, platelets activation and contact activation. Anticoagulant dialyzer was fabricated via skin implantation strategy to implement a chronic renal swine dialysis with heparin free administration. Clotting was significantly inhibited during the whole dialysis session, moreover, the dialyzer showed improved toxins clearance, including urea (~185 mL/min), creatine (~153 mL/min), inorganic phosphorous (~120 mL/min) and β 2 -microglobulin (~110 mL/min). The modified membrane bearing abundant carboxylate groups contributes to excellent hydrophilicity and Ca2+ chelation capability, which is considered to be the predominant anti-clotting mechanism via both intrinsic and extrinsic cascades. The anticoagulant PSf dialyzer demonstrates promising clinical application for heparin free dialysis. • We develop an anti-coagulant dialyzer via constructing a hydrogel skin layer. • The membrane was endowed with carboxylic groups while preserving porous structure. • Both hydrophilicity and Ca2+ chelation enhanced hemocompatibility. • The hydrophilic dialyzer exhibited an improved toxin clearance. • The dialyzer realized the heparin free dialysis for a renal failed swine. [ABSTRACT FROM AUTHOR]

Two dimensional covalent triazine frameworks (2D-CTF) with controlled pore size and stable structure are a new class of 2D building blocks for constructing separation membrane materials. In this work, we synthesize few-layer 2D-CTF-1 nanosheets with high crystallinity and excellent solvent dispersion using a micro-interface method. The as-prepared 2D-CTF-1 membrane via filtration assembly of few-layer 2D-CTF-1 nanosheets exhibits superior permeability due to its ultralow solvent-interface interaction and the abundant in-plane pores, with a water permeance of 141.5 L m−2 h−1 at 1 bar. The skeleton-pores are proved to be the main transfer channels on 2D-CTF-1 membrane, which are stable and nondeformable by external pressure. Size screening based on the cut-off of skeleton-pore (1.39 nm) is also demonstrated, which enables 2D-CTF-1 membrane a huge application potential in precise molecule/ion sieving. Besides, a stable layered structure in aqueous environment renders 2D-CTF-1 membrane with outstanding separation performance in the long-term running, continuously keeping high permeability and selectively. Thus, this work shows a promising application of 2D-CTF-1 as building blocks for 2D membrane construction in the separation field. 2D-CTF-1 membrane with highly ordered skeleton nanopores (intrasheet pathways) as the main transfer channels exhibits robust and precise molecule/ion separation performance. Image 1 • Covalent triazine frameworks membranes were fabricated for precise separation. • The abundant skeleton-pores dominated the mass transfer of 2D-CTF-1 membrane. • Precise molecule sieving was achieved via the skeleton-pores at nano-scale. • 2D-CTF-1 membrane showed stable layered structure and separation performance. [ABSTRACT FROM AUTHOR]

• miR-10b-5p was differentially expressed in SCI models. • miR-10b-5p mediates neuronal apoptosis and autophagy by regulating UBR7. • UBR7 mediates Wnt1 ubiquitination to regulate Wnt/β-catenin to promote apoptosis. • UBR7 mediates Beclin1 ubiquitination to regulate the autophagy level of neuron cells. • miR-10b-5p effectively improves injury and promotes neuron survival in SCI rats. This study aimed to explore the effects of miR-10b-5p on autophagy and apoptosis in neuronal cells after spinal cord injury (SCI) and the molecular mechanism. Bioinformatics was used to analyze the differentially expressed miRNAs. The expression of related genes and proteins were detected by real-time fluorescence quantitative polymerase chain reaction (RT-qPCR) and Western blot, respectively. Cell proliferation was detected by 5-ethynyl-2′-deoxyuridine (EdU), and apoptosis was detected by flow cytometry or terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay (TUNEL). Coimmunoprecipitation confirmed the interaction between UBR7 and Wnt1 or Beclin1. Autophagy was detected by the dansylcadaverine (MDC). The Basso Beattie Bresnahan (BBB) score was used to evaluate motor function, and hematoxylin-eosin (H&E) and Nissl staining were used to detect spinal cord tissue repair and neuronal changes. The result shows that the expression of miR-10b-5p was downregulated in the SCI models, and transfection of a miR-10b-5p mimic inhibited neuronal cell apoptosis. MiR-10b-5p negatively regulated the expression of UBR7, and the inhibitory effect of the miR-10b-5p mimic on neuronal cell apoptosis was reversed by overexpressing UBR7. In addition, UBR7 can regulate apoptosis by affecting the Wnt/β-catenin pathway by promoting Wnt1 ubiquitination. Treatment with the miR-10b-5p mimic effectively improved motor function, inhibited neuronal cell apoptosis, and promoted spinal cord tissue repair in SCI rats. Overall, miR-10b-5p can alleviate SCI by downregulating UBR7 expression, inhibiting Wnt/β-catenin signaling pathway ubiquitination to reduce neuronal apoptosis, or inhibiting Beclin 1 ubiquitination to promote autophagy. [ABSTRACT FROM AUTHOR]

Highlights • Carboxylated cellulose-g-poly(l -lactide) copolymers were synthesized. • The amphiphilic copolymers improved the organic solubility of CCNs. • The copolymers were self-assembled into nanoparticles for oleanolic acid delivery. • The nanoparticles improved the drug solubility and prolonged the drug release. • The nanoparticles maintained the cell inhibition and enhanced antitumor efficiency. Abstract Carboxylated cellulose nanocrystals (CCNs), as one of nanocellulose are promising hydrophilic biomass materials for drug delivery. In this work, a series of amphiphilic carboxylated cellulose-graft-Poly(L-lactide) (CC-g-PLLA) copolymers were synthesized via ring-opening polymerization (ROP) method. The copolymers were characterized by 1H-NMR, FT-IR, WXRD and TGA, and their solubility in organic solvents was improved. Then, these amphiphilic copolymers were self-assembled into nanoparticles for delivery of anticancer drug oleanolic acid (OA). The copolymer (DS PLLA 2.03) nanoparticles displayed the smallest size (196.82 ± 9.14 nm) and the highest drug loading efficiency (24.76 ± 0.58%). The nanoparticles exhibited a spherical shape, well water solubility of OA (16.9 mg/mL) and a prolonged drug release (120 h). In vitro and In vivo study indicated that the nanoparticles maintained cytotoxicity to 4T1 cells and MCF-7 cells and displayed high antitumor efficiency. The amphiphilic CC-g-PLLA copolymer nanoparticles provide a novel platform for drug delivery. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • hNFs biocatalyst was prepared by immobilizing modified laccase. • hNFs biocatalyst activity increased to 165% compared to laccase. • hNFs biocatalyst achieved 375% pH stability and 430% temperature stability. • hNFs biocatalyst catalyzed resveratrol to obtain 45% yield of dimer with no byproduct. • hNFs biocatalyst has higher catalytic yields, specificity than chemical catalyst. Abstract In order to face the increasing demand of laccase with high stability and high performance, laccase was chemically modified by acid anhydride, and copper ion (Ⅱ) was coordinated with the hetero atom of the modified laccase to obtain the nanoflower biocatalyst. The effects of different reaction time, laccase concentration and copper sulfate concentration on the formation of nanoflowers were investigated in detail. Compared to free laccase, the enzyme activity, pH stability and thermal stability of nanoflowers increased by 165%, 375% and 430%, respectively. Furthermore, the catalytic properties of our nanoflower biocatalysts were investigated by catalyzing the synthesis of viniferin. The results showed that a higher yield of 45.0% was obtained in shorter period of time than that of the free laccase (21.6%), and the product was single without other by-products. What's more, nanoflower biocatalyst exhibited excellent storage stability, repeatability and reproducibility in cycle operation. We believed that this study provided a feasible and efficient biocatalytic method for conversion of resveratrol to viniferin. These preliminary results indicated that nanoflowers would have great potential for application in biotransformation and biocatalysis. [ABSTRACT FROM AUTHOR]

A huge amount of red mud was produced in the Aluminum industry which is environmentally hazardous and hard to de-alkalize or recycle due to its enormous amount and low value for recycling. To solve the problem of red mud treatment, a facile, scalable, and environmentally friendly quasi-closed-loop approach for red mud recycling was utilized to recycle it as Li-ion battery anode material by a simply alkali-roasted carbon-coating method, which can effectively solve the problem of red mud treatment and recycle it as high-value Li-ion anode material. Alkali-roasted carbon-coating red mud (RA/C) shows remarkable electrochemical performance compared to current works related to red mud recycling and ferrosilicon-based anode materials, the initial reversible charge capacity reaches 1746 mA h g−1 at 0–3 V under 0.1 A g−1. Cycle-driven and pseudocapacitance-boosted enable RA/C to exhibit outstanding rate performance (1106 mA h g−1 at 10 A g−1 after 259 cycles compared to 910 mA h g−1 for initial discharge) and cycling performance (2538 mA h g−1 at 1 A g−1 after 500 cycles compared to 830 mA h g−1 for initial discharge). This work discussed dual mechanisms of cycle-driven and pseudocapacitance-boosted by dQm/dV plots, GITT (Galvanostatic Intermittent Titration Technique), and pseudocapacitance contribution measurement, revealing that higher cutoff potential induces electrochemical performance changes. The results show that the activation of the silicon oxide phase in 0–3 V promotes capacity increases in long-term cycling and capacitive contribution increases in 0–3 V significantly enhance the high current density discharge ability. Those attributes of red mud-based anode material become a promising candidate for low-cost and high-energy-density Li-ion batteries. This work provides estimations of economic feasibility and environmental impact, results show that quasi-closed-loop has high economic feasibility and low CO 2 -Eq. emission of 1.525 kg CO 2 -Eq. per kg RA/C compared to 9.616 kg CO 2 -Eq. per kg natural graphite of conventional natural graphite. This work proposed a feasible, sustainable, and scalable red mud recycling approach that promotes green and sustainable development of the Aluminum industry. [Display omitted] • Discover cycle-driven and pseudocapacitance-boosting mechanisms for red mud-based anode. • Estimate the cost and revenues, greenhouse gas emissions of the quasi-closed-loop approach. • Recycling red mud via a low-cost, facile, scalable, and environmentally friendly method. [ABSTRACT FROM AUTHOR]

• Orifice flow noise appears in two reverse flows of vortex areas of the pipe. • The SPL of orifice flow noise increases over velocity logarithmically. • Smaller orifice leads to higher SPL, while orifice thickness causes faint influence. Based on the previous measurements data, the standard orifice flowmeters is one of the main noise sources in nature gas metering stations. In this paper, a theoretical method that combines the Large Eddy Simulations (LES) with the Ffowcs Williams Hawkings (FW-H) acoustic analogy theory has been used to analysis the Sound Pressure Level (SPL) distribution in standard orifice flowmeter. And then, a series of numerical simulations have been performed over a range of conditions, including medium velocity, aperture size, and orifice thickness. At last, a correlation formula of the maximum SPL and medium velocity has been presented by fitting the numerical results. It shows that the SPL increases over velocity logarithmically, and the maximum SPL is present at the upstream wall of orifice and in two reverse flows of vortex areas of the downstream pipe. Meanwhile, a smaller aperture size leads to higher SPL, while orifice thickness brings about faint influence. The SPL increases by about 8 dB by the decreasing of aperture per 20 mm. Finally, the data obtained from the fitting are verified by field data and is approved by the staff. The results provide effective guidance for practical operation of orifice flowmeter noise prevention and control. [ABSTRACT FROM AUTHOR]