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To improve performance of membrane electrode assembly (MEA) at large current density region, efficient mass transfer at the cathode is desired, for which a feasible strategy is to lower catalyst layer thickness by constructing high loading Pt-alloy catalysts on carbon. But the high loading may induce unwanted particle aggregation. In this work, H-PtNi/C with 33% (mass) Pt loading on carbon and monodisperse distribution of 3.55 nm PtNi nanoparticles, was prepared by a bimodal-pore route. In electrocatalytic oxygen reduction reaction (ORR), H-PtNi/C displays an activity inferior to the low Pt loading catalyst L-PtNi/C (13.3% (mass)) in the half-cell. While in H2-O2 MEA, H-PtNi/C delivers the peak power density of 1.51 W·cm−2 and the mass transfer limiting current density of 4.4 A·cm−2, being 21% and 16% higher than those of L-PtNi/C (1.25 W·cm−2, 3.8 A·cm−2) respectively, which can be ascribed to enhanced mass transfer brought by the thinner catalyst layer in the former. In addition, the same method can be used to prepare PtFe alloy catalyst with a high-Pt loading of 36% (mass). This work may lead to a range of catalyst materials for the large current density applications, such as fuel cell vehicles.

Conventional gels manifest monotonous swelling or shrinking performance upon immersing in solvents until reaching an equilibrium state. Recently, we discovered that the “hydrophobic hydrogels” prepared from hydrophobic polymer networks demonstrated dynamic swelling performance without equilibrium states. Upon water immersion, the gels expanded tremendously at the first stage until reaching a swelling peak; subsequently, the gels shrunk at an extremely slow rate. While this phenomenon endows the material with an unusual feature, more efforts are highly demanding for the full understanding of this performance. Herein, we systematically investigate the hydrophobic hydrogels’ swelling kinetics by screening the organic solvent dependence, polymer effect, and temperature impact. It is revealed that the chemical structure of gels greatly influences the swelling kinetics. The higher the networks’ hydrophobicity, the slower the swelling kinetics. Meanwhile, organic solvents demonstrate a limited effect on the dynamic swelling performance. Moreover, higher temperature significantly accelerates the whole volume change process. Based on the swelling performance, we further develop hydrogel-based soft devices with time-programmable two-dimensional and three-dimensional shape-shifting performances.

Fluorescent dyes such as rhodamine R6G usually suffer from quenching caused by aggregation in the solid state. Herein, we enhance the solid state luminescence of R6G by controlling assemblies of rhodamine R6G and [Mo8O26]4− based on the synergies between the anchoring and diluting effects. In addition, the hybrids represent reversible transformation and tunable luminescence by different loadings of the rhodamine 6G dye within the [Mo8O26]4− architecture. This work provides new ideas for the structural design, synthesis and transformation of POM-based hybrid materials, opening the way towards the design of novel multifunctional hybrid systems.

A new type of explosive ink formulation that can be quickly cured was prepared with unsaturated polyester as binder, styrene as active monomer, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide as photoinitiator, and hexanitrohexaazaisowurtzitane (CL-20) as the main explosive. Then the explosive ink direct writing technology was used to charge the micro-sized energetic devices, the curing mechanism of the explosive ink was discussed, and the microstructure, safety performance and explosive transfer performance of the explosive ink molded samples were tested and analyzed. Results indicate that the composite material has a fast curing molding speed, its hardness can reach 2H within 8 min. The crystal form of CL-20 in the molded sample is still e type. The CL-20 based UV-curing explosive ink formulation has good compatibility, its apparent activation energy is increased by about 3.5 kJ/mol. The composite presents a significant reduction in impact sensitivity and its characteristic drop height can reach 39.8 cm, which is about 3 times higher than the raw material. When the line width of charge is 1.0 mm, the critical thickness of the explosion can reach 0.015 mm, and the explosion velocity is 7129 m/s when the charge density is 1.612 g/cm3.

Practical implementations of rechargeable lithium (Li) metal batteries have long been plagued by multiple problems of Li anode, such as Li dendrite growth, large volume change, low Coulombic efficiency. Here, we report a protein-enabled film that can provide effective protection for Li metal. The protective film with an integrated design of high flexibility, strong adhesion and high Li-ion transference number (0.80) is fabricated by incorporating denatured zein (corn protein) with polyethylene oxide (PEO) acting as an agent for sustaining the denatured protein chains against refolding via the intermolecular interactions between them. Thus, a conformable zein-enabled protective film (zein@PEO) with simultaneous enhancement in flexibility, modulus and adhesion strength is generated to offer both functions of self-adapting and anion-anchoring abilities. The results show that the zein@PEO film is able to accommodate the volume change, reduce the side reactions, and homogenize the ion deposition. Benefiting from these significant properties/functions, the Li/Cu cell with the zein@PEO film delivers prolonged cycle life for over 500 hours with stable performance. Paired with LiMn2O4 cathode, the capacity, cycle stability and rate performance of the cell are remarkably improved as well, demonstrating the effectiveness in stabilizing Li metal batteries.

PURPOSE This study systematically reviewed the literature to compare the bond strength of resin composites with that of zirconia-reinforced lithium silicate (ZLS) and lithium disilicate (LD). STUDY SELECTION This review was structured based on the Preferred Reporting Items for Systematic Reviews and MetaAnalyses (PRISMA 2020) statement. This study was registered at the International Prospective Register of Systematic Reviews (CRD42021256900). Studies were searched via PubMed, Web of Science, and Google Scholar databases without language or publication year limits. In vitro studies that evaluated the bond strength of the resin composites to ZLS and LD were included. The risk of bias in all the included articles was evaluated. Statistical analyses were performed using the Review Manager software (version 5.3, Cochrane Collaboration, Oxford, UK). RESULTS Of the 90 potentially related articles, the full texts of 16 articles were evaluated after screening. Finally, sevenstudies were included in the qualitative synthesis and meta-analysis. All the studies presented a medium risk of bias. The results showed no significant difference in bond strength between the ZLS and LD groups (P = 0.94, mean difference=0.08, and 95% confidence interval=-1.93 to 2.10). However, a significant difference was found in the subgroup analysis considering different types of aging treatments (P = 0.0008) and different types of bond strength tests (P < 0.00001). CONCLUSION The bond strength of resin composites was found to be similar to that of ZLS and LD, but different aging treatments and bond strength tests exhibited varying effects on the bond strength.

Rechargeable lithium metal batteries (LMBs) are faced with concerns of safety and short lifespan because of the uncontrollable growth of lithium (Li) dendrites. Natural biomolecules enriched with diverse polar groups are likely to have high lithiophilicity, showing the potential to suppress the dendrite growth. However, besides the chemical compositions, their structural diversities from nature induce notable impacts on the functions, which has not been studied yet. Here, through experiments and molecular simulations, we discover a natural “relief” for Li dendrites, zein protein, and successfully strengthen its dendrite-suppressing ability by tailoring its configurations to achieve long-life Li anodes. The “strong relief configuration” (SRC-Zein) is generated via drastically unfolding and opening the compact protein structure using a powerful denaturant. Modifying the separator by SRC-Zein results in excellent electrolyte wettability, higher ionic conductivity (2.0 mS/cm), and higher Li+ transference number (0.68), compared with the less unfolded protein. These important properties play the synergistical role in homogenizing the ion deposition and inhibiting the nucleation/growth of Li dendrites. As a result, the symmetrical Li/Li cell exhibits exceptional cycling stability for more than 1400 h at 2 mA/cm2. Furthermore, the half-cell with the SRC-Zein modified separator shows significant enhancement in capacity, cycle stability, and rate performance.

A 220-GHz power amplifier (PA) with high gain, high output power, and high efficiency for a 220-GHz transceiver system is presented in this letter. At terahertz (THz) and sub-terahertz (sub-THz) bands, the maximum available gain/maximum stable gain (MAG/MSG) of the device degrades rapidly, which increases the difficulty of high-gain and high-efficiency PA design. In this letter, the gm-boosting technique is analyzed and used in differential cascode (CC) topology to boost the gain of the single stage. Metal–oxide–metal (MOM) capacitors are used to reduce the insertion losses of the matching networks, therefore enhancing the gain and efficiency. The proposed PA exhibits a measured gain of 22.5 dB at 225 GHz with a 3-dB bandwidth of 35 GHz from 204 to 239 GHz. The measured OP1dB of 6.0 dBm and the peak power added efficiency (PAE) of 2.96% are achieved at 215 GHz. The measured $P_{\mathrm {sat}}$ is larger than 9 dBm from 200 to 216 GHz. The PA occupies a small area of 0.162 mm2 with a compact core area of 0.069 mm2. The power consumption of the chip is 245 mW. From the aspect of overall performances, including gain, output power, efficiency, and chip area, this work exhibits one of the best performances in silicon-based PAs at sub-THz bands. Besides, to the best of our knowledge, the proposed PA exhibits the highest efficiency in silicon-based implementations beyond 210 GHz.

Decoupling the ion motion and segmental relaxation is significant for developing advanced solid polymer electrolytes with high ionic conductivity and high mechanical properties. Our previous work proposed a decoupled ion transport in a novel protein-based solid electrolyte. Herein, we investigate the detailed ion interaction/transport mechanisms through first-principles density functional theory (DFT) calculations in a vacuum space. Specifically, we study the important roles of charged amino acids from proteins. Our results show that the charged amino acids (i.e., Arg and Lys) can strongly lock anions (ClO4-). When locked at a proper position (determined from the molecular structure of amino acids), the anions can provide additional hopping sites and facilitate Li+ transport. The findings are supported from our experiments of two protein solid electrolytes, in which the soy protein (with plenty of charged amino acids) electrolyte shows much higher ionic conductivity and lower activation energy in comparison to the zein (lack of charged amino acids) electrolyte.

Coordination compounds are very promising as energetic materials and catalysts for improving the comprehensive performance of solid propellants. In this study, to obtain insensitive energetic materials with excellent performance, graphene oxide (GO) as template, nitrogen-rich 3-amino-1,2,4 triazole (AMTZ) and Co(NO3)2·6H2O as ligands, a new energetic coordination compound (GO + Co + AMTZ) was synthesized. The morphology, molecular structure, element, and thermal decomposition property of the product were characterized by scanning electron microscope, X-ray diffractometer, Fourier transform infrared (FTIR), Raman spectra, X-ray photoelectron spectroscopy, differential scanning calorimetry (DSC), and thermogravimetry analysis (TG). The results showed that Co ions are used as bridges to coordinate with the O atoms of the hydroxyl and carboxyl groups on the GO surface and the N atoms of AMTZ, respectively. GO + Co + AMTZ has good thermal stability, high heat release, and insensitivity. And the catalytic effect of GO + Co + AMTZ to AP was studied using DSC. Compared with pure AP, the decomposition peak temperature of GO + Co + AMTZ/AP moved forward to 299.57 °C, and the heat release increased to 4935 J g−1, which indicated that GO + Co + AMTZ has an obvious catalytic effect. In addition, the gas phase decomposition products of GO + Co + AMTZ were tested using TG-IR, and the catalytic mechanism was further analyzed. The NO2 gas produced by the thermal decomposition could oxidize the dissociation product NH3 of AP, thereby accelerating the thermal decomposition of AP. Overall, due to its higher energy, insensitivity, and high-energy catalysis, GO + Co + AMTZ has potential application prospects in solid propellants.

The gut microbiota is widely considered to be involved in several diseases, including atherosclerosis, obesity, chronic obstructive pulmonary disease (COPD) and pulmonary arterial hypertension (PAH). This study aimed to determine if changes in the gut microbiome and metabolome play a major role in the early pathogenesis of PAH. Male Wistar rats were injected with monocrotaline (MCT) (55 mg/kg) at day 1 and injected with calcium-sensing receptor (CaSR) antagonist NPS2143 (4.5 mg/kg/d) from days 1 to 21. Fecal samples were obtained. The gut microbiota and metabolome were analyzed by 16S rRNA gene sequencing and mass spectrometry-based analysis to investigate the effect of PAH in this rat model. MCT injection had a marked effect on the composition of the gut microbiota. This finding was further confirmed by metabolomic analysis with identification of several metabolites relevant to the gut microflora. However, NPS2143 partially abrogated this intestinal flora disorder and reversed fecal metabolite abnormalities. In conclusion, our study shows correlations between changes in the gut microbiome and the metabolome in PAH, which are affected by NPS2143., Graphical abstract

The selective synthesis of energetically less favorable ring-shaped nanostructures by liquid phase synthetic chemistry is a huge challenge. Herein, we report a precise synthesis of carbon nanorings with a well-defined morphology and tunable thickness based on asymmetric intramicellar phase-transition-induced tip-to-tip assembly via mixing hydrophobic long-chain octadecanol and block copolymer F127. This orientational self-assembly depends on the hydrophobicity difference of the intermediate’s surface, which triggers directional interactions that surpass the entropy cost of undesired connections and help assemble intermediates into defined ringlike structures. Based on a ringlike template, carbon nanorings with adjustable sizes can be attained by changing synthetic variables. More importantly, diverse units including crescentlike, podlike, and garlandlike nanostructures can also be created through controlling the kinetics of the self-assembly process. This discovery lays a solid foundation for the challenging construction of such a precise configuration on the nanoscale, which would not only promote fundamental studies but also pave the way for the development of advanced nanodevices with unique properties., Carbon nanorings with a well-defined morphology and tunable thickness have been selectively synthesized via asymmetric intramicellar phase-transition-induced tip-to-tip assembly.

Background: In Traditional Chinese Medicine (TCM), the heads and tails of Angelica sinensis (Oliv.) Diels (AS) is used in treating different diseases due to their different pharmaceutical efficacies. The underline mechanisms, however, have not been fully explored. Objective: Novel mechanisms responsible for the discrepant activities between AS heads and tails were explored by a combined strategy of transcriptomes and metabolomics. Method:: Six pairs of the heads and tails of AS roots were collected in Min County, China. Total RNA and metabolites, which were used for RNA-seq and untargeted metabolomics analysis, were respectively isolated from each AS sample (0.1 g) by Trizol and methanol reagent. Subsequently, differentially expressed genes (DEGs) and discrepant pharmaceutical metabolites were identified for comparing AS heads and tails. Key DEGs and metabolites were quantified by qRT-PCR and targeted metabolomics experiment. Results: Comprehensive analysis of transcriptomes and metabolomics results suggested that five KEGG pathways with significant differences included 57 DEGs. Especially, fourteen DEGs and six key metabolites were related to the metabolic regulation of Phenylpropanoid biosynthesis (PB) pathway. Results of RT-qPCR and targeted metabolomics indicated that higher levels of expression of crucial genes in PB pathway, such as PAL, CAD, COMT and peroxidase in the tail of AS, were positively correlated with levels of ferulic acid-related metabolites. The average content of ferulic acid in tails (569.58±162.39 nmol/g) was higher than those in the heads (168.73 ± 67.30 nmol/g) (P˂0.01); Caffeic acid in tails (3.82 ± 0.88 nmol/g) vs heads (1.37 ± 0.41 nmol/g) (P˂0.01), and Cinnamic acid in tails (0.24 ± 0.09 nmol/g) vs heads (0.14 ± 0.02 nmol/g) (P˂0.05). Conclusion: Our work demonstrated that overexpressed genes and accumulated metabolites derived from PB pathway might be responsible for the discrepant pharmaceutical efficacies between AS heads and tails.

Silica-based aerogel composite was prepared adopting sol–gel technique combined with atmospheric drying method utilizing waste environmentally hazardous iron tailings. High-temperature alkali fusion was applied to extract the Si, Al and Fe in the tailings so as to maximize recovery of valuable elements. The SiO2-Al2O3 (SA) and SiO2-Al2O3-Fe2O3 (SAF) aerogel composites were subjected to assess its adsorption capacity for macromolecules, utilizing methylene blue (MB) as the adsorbate. The specific surface areas of the SA and SAF aerogel were estimated to be 922.03 m2/g and 683.84 m2/g. The equilibrium adsorption capacity for MB was estimated to be 318.47 mg/g and 334.44 mg/g, respectively. Although the specific surface area of SAF was lower than SA, it offered higher MB adsorption capacity which could be attributed to the presence of iron oxide. The results promised utilization of iron tailing generated aerogel composite as a potential adsorbent for separation of high molecular weight compounds.

A new hydrophilicity and negatively charged polytetrafluoroethylene (PTFE) fiber membrane has been developed and characterized. Specifically, the dopamine (DA) and polyethylenimine (PEI) were co-deposited onto the PTFE fiber membrane surface via covalent connection. Then the amine groups of the membrane surface were reacted with anhydride groups of poly(ethylene-alt-maleic anhydride) (PEMA). Last, unreacted anhydride groups have hydrolysis and ionization. The preparation membrane has been investigated and confirmed by using XPS, ATR-FTIR, SEM, Zeta potential analyzer, pore size analyzer water contact angle, respectively. The results showed that the membranes were endowed with excellent hydrophilicity and negatively charged. It has high separation efficiency and permeation flux for oil-in-water emulsion containing cationic emulsifiers, and excellent anti-fouling property.

The shuttling of polysulfides is the most detrimental contribution to degrading the capacity and cycle stability of lithium-sulfur (Li-S) batteries. Adding a carbon interlayer to prevent the polysulfides from migrating is feasible, and a rational design of the structures and surface properties of the carbon layer is essential to increasing its effectiveness. Herein, we report a hierarchical porous carbon (HPC) created by carbonization of bis(phenoxy)phosphazene and in-situ doping of triple heteroatoms into the carbon lattice to fabricate an effective polysulfide-trapping interlayer. The generated carbon integrates the advantages of a hierarchical porous structure, a high specific area and rich dopants (N, O and P), to yield chemisorption and physical confinement for polysulfides and fast ion-transport synergistically. The HPC interlayer significantly improves the electrochemical performance of Li-S batteries, including an exceptional discharge capacity of 1509 mA h/g at 0.06 C and a high capacity retention of 83.7 % after 250 cycles at 0.3 C. This work thus proposes a facile in-situ synthesis of heteroatom-doped carbon with rational porous structures for suppressing the shuttle effect.

Bone mass loss (osteoporosis) seen in postmenopausal women is an adverse factor for implant denture. Using an ovariectomized rat model, we studied the mechanism of estrogen-deficiency-caused bone loss and the therapeutic effect of Zoledronic acid. We observed that ovariectomized-caused resorption of bone tissue in the mandible was evident at four weeks and had not fully recovered by 12 weeks post-ovariectomized compared with the sham-operated controls. Further evaluation with a TUNEL assay showed ovariectomized enhanced apoptosis of osteoblasts but inhibited apoptosis of osteoclasts in the mandible. Zoledronic acid given subcutaneously as a single low dose was shown to counteract both of these ovariectomized effects. Immunohistochemical staining showed that ovariectomized induced the protein levels of RANKL and the 65-kD subunit of the NF-κB complex mainly in osteoclasts, as confirmed by staining for TRAP, a marker for osteoclasts, whereas zoledronic acid inhibited these inductions. Western blotting showed that the levels of RANKL, p65, as well as the phosphorylated form of p65, and IκB-α were all higher in the ovariectomized group than in the sham and ovariectomized + zoledronic acid groups at both the 4th- and 12th-week time points in the mandible. These data collectively suggest that ovariectomized causes bone mass loss by enhancing apoptosis of osteoblasts and inhibiting apoptosis of osteoclasts. In osteoclasts, these cellular effects may be achieved by activating RANKL-NF-κB signalling. Moreover, zoledronic acid elicits its therapeutic effects in the mandible by counteracting these cellular and molecular consequences of ovariectomized.

The crystallization behavior of Li2O-Al2O3-SiO2 glasses with various concentration of Li2O were investigated by DSC, XRD, and FE-SEM. The h/l-quartz s.s. is the main crystalline phase for all of the glass with the heat treatment of 720 °C/3 h+800°C/1.5 h while the crystallinity and crystal size increase with the increase of Li2O contents. Due to the negative thermal expansion coefficient of h/l-quartz s.s., the thermal expansion coefficient of glass-ceramics decreases with the increasing of Li2O contents. When the Li2O content is 9mol%, the near-zero CTE20–700 °C= −0.09 × 10−6 °C−1 is obtained upon the heat treatment of 720 °C/3 h+800 °C/1.5 h. The crystallization activation energy of the glass with 9mol% Li2O is about 351 kJ/mol, and the crystallization mechanism is volume crystallization.

Pulmonary hypertension (PH) is characterized by pulmonary vascular remodeling, which exists in both pulmonary arteries and pulmonary veins. Pulmonary vascular remodeling stems from excessive proliferation of pulmonary vascular myocytes. Platelet-derived growth factor-BB (PDGF-BB) is a vital vascular regulator whose level increases in PH human lungs. Although the mechanisms by which pulmonary arterial smooth muscle cells respond to PDGF-BB have been studied extensively, the effects of PDGF-BB on pulmonary venous smooth muscle cells (PVSMCs) remain unknown. We herein examined the involvement of calcium sensing receptor (CaSR) in PDGF-BB-induced PVSMCs proliferation under hypoxic conditions. In PVSMCs isolated from rat intrapulmonary veins, PDGF-BB increased the cell number and DNA synthesis under normoxic and hypoxic conditions, which was accompanied by upregulated CaSR expression. The influences of PDGF-BB on proliferation and CaSR expression in hypoxic PVSMCs were greater than that in normoxic PVSMCs. In hypoxic PVSMCs superfused with Ca(2+)-free solution, restoration of extracellular Ca(2+) induced an increase of [Ca(2+)](i), which was significantly smaller than that in PDGF-BB-treated hypoxic PVSMCs. The positive CaSR modulator spermine enhanced, whereas the negative CaSR modulator NPS2143 attenuated, the extracellular Ca(2+)-induced [Ca(2+)](i) increase in PDGF-BB-treated hypoxic PVSMCs. Furthermore, the spermine enhanced, whereas the NPS2143 inhibited, PDGF-BB-induced proliferation in hypoxic PVSMCs. Silencing CaSR with siRNA attenuated the extracellular Ca(2+)-induced [Ca(2+)](i) increase in PDGF-BB-treated hypoxic PVSMCs and inhibited PDGF-BB-induced proliferation in hypoxic PVSMCs. In conclusion, these results demonstrated that CaSR mediating PDGF-BB-induced excessive PVSMCs proliferation is an important mechanism involved in the initiation and progression of PVSMCs proliferation under hypoxic conditions.

Cellulose nanocrystals (CNCs) not only have environmental protection characteristics of being lightweight, degradable, green, and renewable but also have some nanocharacteristics of high strength, large specific surface area, and obvious small size effect, so they are often used as a reinforcing agent in various polymers. However, the hydrogen bonding between CNC molecules is relatively strong, and they can easily aggregate and get entangled with each other. In this work, several large-porosity composite nanofiber films, KH550-CNC/waterborne polyurethane (WPU)/poly(vinyl alcohol) (PVAL) with KH550-modified CNCs, are prepared using poly(vinyl alcohol) (PVAL) solution and electrospinning technology. A variety of characterization methods are used to discuss and analyze the nanofiber materials, and the effects of the added amount of CNCs modified with KH550, spinning voltage, curing distance, and advancing speed on the morphology and performance of composite fibers are discussed separately. The results show that when the content of KH550-CNC is 1%, the composite fiber film obtained has the most regular morphology and the best spinnability, which is convenient for the specific application of fiber materials in a later period. In addition, the porosity of the obtained composite fiber film is 62.61%. Therefore, this work provides a theoretical basis and research strategy for the preparation of higher-porosity composite films as well as the development of new textile materials.

One-dimensional (1D) metal-organic nanostructures hold great promise for preparing various 1D carbon/metal derivatives toward various electrocatalysis including oxygen reduction reaction (ORR); but it is challenging to synthesize them. Herein, 1D cobalt(Co)-metal-organic nanowires are prepared using the complex of Co2+ and 1, 2, 4-triazole. Direct carbonization of the as-prepared nanowires affords a well-defined structure of Co nanoparticles encapsulated inside the bamboo-liked 1D carbon nanostructure, i.e., carbon nanobamboos (Co@CNB). Owing to the outstanding electronic transport in bamboo-liked carbon structure, strong electronic coupling between the N-doped carbon and Co nanoparticles, the Co@CNB catalyst exhibits an excellent ORR performance comparable to the commercial Pt/C in alkaline solution. Density functional theory (DFT) calculations reveal that the Co@CNB can strengthen the adsorption of all adsorbates (O*, OH* and OOH*) compared with a carbon nanotube, benifical for oxygen protonation and thus enhancing the ORR activity. Moreover, it is possible to outperform Pt intrinsically if the curvature of carbon shell is high enough in Co@CNB. Lastly, the zinc-air battery (ZAB) fabricated with Co@CNB as the cathode catalyst shows a higher peak power density and better cycling durability than those of the ZAB with Pt/C; suggesting the great potential of Co@CNB as efficient electrocatalysts for metal-air batteries. National Research Foundation (NRF) Accepted version This work was supported by Nanyang Technological University under NAP award (M408050000) and Singapore Ministry of Education Tier 1 program (2018-T1-001-051). Part of this work was conducted within the Delta-NTU Corporate Lab for Cyber-Physical Systems with funding support from Delta Electronics Inc. and the National Research Foundation (NRF) Singapore under the Corp Lab@University Scheme. J.X. acknowledges the financial supports from the National Natural Science Foundation of China (21802124, 91845103, and 91945302), the Strategic Priority Research Program of the Chinese Academy of Sciences (No. XDB36030200), and the Liaoning Revitalization Talents program (No. XLYC1907099), and the fund of the State Key Laboratory of Catalysis in DICP (No. N-19-13), the Ministry of Science and Technology of China (No. 2018YFA0704503).

An O2 self-evolving core-shell theranostic nanohybrid was developed by encapsulating a nanoenzyme cerium oxide (CeOx) in a metal-organic framework (MOF). The hybrid reveals a 9-fold higher apoptotic percentage than bare CeOx in a harsh hypoxic microenvironment through tandem homogenous catalysis. Simultaneously, the oxygen-promoted therapeutic efficiency was self-monitored by the hybrid with caspase-3 activation, paving the way for MOF-functionalized nanoenzymes in theranostics.

The immobilization of photocatalysts is considered an effective approach to solve the problem of the difficult recycling of powdered nanocatalysts after photocatalytic degradation. In this paper, tin dioxide/titanium dioxide (SnO2/TiO2) composite nanoparticles with excellent photodegradation performance and poly(vinylidene fluoride) (PVDF) resin were used as raw materials to prepare composite membranes for the catalytic degradation of rhodamine B (RhB) dye via a non-solvent-induced phase separation method. Specifically, the basic properties of SnO2/TiO2 composite nanoparticles were systematically analyzed, the photocatalytic performance of SnO2/TiO2/PVDF composite membranes was thoroughly investigated, and the photocatalytic mechanism has been revealed. Experimental results showed that the SnO2/TiO2 composite photocatalyst demonstrates a higher photocatalytic activity than the single photocatalyst with the SnO2/TiO2 composite comprising Sn/Ti in a molar ratio of 1 : 6, showing the highest photocatalytic performance. After SnO2/TiO2 composite particles were used as a kind of raw material for the production of PVDF membrane, the photocatalytic degradation rate of RhB by the SnO2/TiO2/PVDF composite membrane was as high as 91.84%. Moreover, ˙OH and h+ play a very important role in the whole photocatalytic degradation process. In summary, this paper will provide an effective guidance to improve the photocatalytic degradation of SnO2/TiO2/PVDF composite membranes, which will ultimately provide a broad potential application of photocatalysis in the field of water treatment.

Ossification of ligaments (OL) and osteoporosis (OP) are multifactorial disorders without definitive clinical biomarkers. Long non-coding RNAs (lncRNAs) are known to involve in regulating pathogenesis. Here, we have identified a preosteoblast-enriched lnc-Evf2 that was overexpressed in ossified ligamentum flavum (OLF) and down-expressed in OP. lnc-Evf2 is gradually upregulated during osteogenic induction, correlating with the enhanced expression of osteogenic marker genes and matrix mineralization. Moreover, knockdown of lnc-Evf2 significantly inhibits the expression of osteogenic differentiation markers and delays the osteoblastic mineralization process, indicating that this molecule is involved in osteogenesis. Mechanistically, we demonstrated that silencing of lnc-Evf2 decreases the protein level but not the mRNA levels of Notch2, Notch3, and Hes1, all of which correlate with osteogenesis. Taken together, our data demonstrate that lnc-Evf2 promotes osteogenic differentiation and bone formation through the Notch signaling, revealing that lnc-Evf2 may serve as a novel potential clinical target of OL and OP.

Electrochemical production of H2O2 from O2 using simulated seawater provides a promising alternative to the energy-intensive industrial anthraquinone process. In this study, a flow cell system is built for electrocatalytic production of H2O2 under an air atmosphere in simulated seawater using cobalt single-atom catalysts (Co SACs). The Co SACs can achieve a high H2O2 production rate of 3.4 mol gcatalyst−1 h−1 under an air flow at a current density of 50 mA cmgeo−2 and long-term stability over 24 h in 0.5 M NaCl. It is found that Co–N5 rather than the Co–N4 structure in Co SACs is the main active site for H2O2 formation in the two-electron oxygen reduction reaction (ORR) pathway. It also shows high chloride-endurability without inhibition of the ORR process in simulated seawater. The fast production of H2O2 on Co–N5 sites in a flow cell provides a promising path of electrocatalytic oxygen reduction in simulated seawater, eventually converting ubiquitous air and seawater towards energy sustainability.