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A technique for monitoring chemical oxygen demand (COD), total nitrogen (TN), ammonia (N-NH4), and phosphate (P-PO4) in surface water with a targeted signal multielectrode system (Cu, Ir, Rh, Co(OH)2, and Zr(OH)4 electrodes) is proposed for the first time. Each water quality index is specifically detected by at least two electrodes with distinct selectivity sensing mechanisms. Cyclic voltammetry and electrochemical impedance measurements are employed for multidimensional signal acquisition, complemented by normalization and Least Absolute Shrinkage and Selection Operator (LASSO) for principal feature extraction and dimension reduction. Multiple linear regression (MLR), partial least-squares (PLS), and eXtreme Gradient Boosting (XGBoost) were employed to evaluate the established prediction model. The precisions of the multielectrode system are ±10%/±5 ppm of COD, ±10%/±0.2 ppm of TN, ±5%/±0.1 ppm of N-NH4, and ±5%/±0.01 ppm of P-PO4. The analysis time of the multielectrode system is reduced from hours to minutes compared with traditional analysis, without any sample pretreatment, facilitating continuous online monitoring in the field. The developed multielectrode system offers a feasible strategy for online in situ monitoring of surface water quality.

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In this work, a chemical grafting polymerization method was employed to synthesize EHPMC-g-PANI self-supporting films. Polyaniline (PANI) was grafted onto hydroxypropyl methylcellulose (HPMC) modified with epichlorohydrin (EPHMC) to obtain an EHPMC-g-PANI aqueous dispersion, which was subsequently dried to form the self-supporting films. The introduction of HPMC, with its excellent film-forming ability and mechanical strength, successfully addressed the poor film-forming ability and mechanical properties intrinsic to PANI. Compared to in situ polymerized HPMC/PANI, the EHPMC-g-PANI exhibited significantly improved storage stability. Moreover, the fabricated EHPMC-g-PANI films displayed a more uniform and smoother morphology. The conductivity of all the films ranged from 10-2 to 10-1 S/cm, and their tensile strength reached up to 36.1 MPa. These results demonstrate that the prepared EHPMC-g-PANI holds promising potential for applications in various fields, including conductive paper, sensors, and conductive inks.

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Fracture healing is a very complex physiological process involving multiple events at different temporal and spatial scales, such as cell migration and tissue differentiation, in which mechanical stimuli and biochemical factors assume key roles. With the continuous improvement of computer technology in recent years, computer models have provided excellent solutions for studying the complex process of bone healing. These models not only provide profound insights into the mechanisms of fracture healing, but also have important implications for clinical treatment strategies. In this review, we first provide an overview of research in the field of computational models of fracture healing based on CiteSpace software, followed by a summary of recent advances, and a discussion of the limitations of these models and future directions for improvement. Finally, we provide a systematic summary of the application of computational models of fracture healing in three areas: bone tissue engineering, fixator optimization and clinical treatment strategies. The application of computational models of bone healing in clinical treatment is immature, but an inevitable trend, and as these models become more refined, their role in guiding clinical treatment will become more prominent.

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Phytochemical investigation on the aerial parts of Corydalis impatiens (pall.) Fisch (Papaveraceae) resulted in the identification of four previous undescribed benzylisoquinoline alkaloids, impatienines A-D (1-4), together with 14 known analogues (5-18). The structures of these compounds were elucidated by extensive spectroscopic analysis (IR, HR-ESIMS, 1D- and 2D-NMR) as well as ECD calculations. All the compounds obtained were investigated for their inhibitory effect on the growth of A549, H1299 and HepG2 cancer cells. Compounds 7 and 15 exhibited pronounced inhibition against the A549 cancer cells with IC50 values of 6.81 µM and 3.17 µM, while the positive control cisplatin was 1.83 µM. Compounds 1-3 showed moderate inhibitory on the H1299 cancer cells. Compounds 4, 10-12, and 16 showed signiffcant activity against HepG2 cancer cells with IC50 values range of 4.41-8.75 µM.

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Four new compounds, impatienines E-H (1-4), together with 18 known ones (R)-N-methylcoclaurine (5), impatienine I (6), thalifoline (7), iseluxine (8), pisoquinoline (9), corydaldine (10), northalifoline (11), noroxyhydrastinine (12), 6,7-methylenedioxy-1(2H)-isoquinolinone (13), N-methylcorydaldine (14), oxyhydrastinine (15), corypalline (16), N-trans-feruloylmethoxytyramine (17), N-trans-feruloyldopamine (18), N-trans-feruloyltyramine (19), N-trans-sinapoyltyramine (20), N-cis-feruloyltyramine (21), N-cis-sinapoyltyramine (22) were obtained from the aerial parts of Corydalis impatiens (pall.) Fisch. Their structures were elucidated by extensive spectroscopic analysis (1D- and 2D-NMR, HR-ESIMS, IR, UV) and/or comparison with reported literature. The inhibitory effects of these isolates were also evaluated against the growth of cancer cells (A549, H1299 and HepG2). Compounds 2 and 4 showed significant inhibitory effect on HepG2 cancer cells with IC50 values of 8.62, 8.32 µM, respectively (positive control cisplatin: IC50, 6.32 µM). Compounds 22 and 4 exhibited moderate inhibitory effects against A549 cancer cells, and the IC50 values were 7.78 and 12.54 µM, respectively (positive control cisplatin: IC50, 1.83 µM).

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The next-generation 650 MHz solid state power amplifier designed by the Institute of Modern Physics will utilize 24 modules with an output power of 60 kW. The outputs of each of the 12 modules will be combined using a 12-in-1 rectangular cavity combiner integrated into the rack. This cavity combiner, requiring only a single stage to combine power, is characterized by a minimal power loss and a high combining efficiency. The input couplers of the combiner are adjustable to change the number of combination channels. In the event of one amplifier module failure, the corresponding port can be adjusted to decouple, transforming the combiner to an (N-1)-channel combiner with a combining efficiency decay of 0.2%. The prototype of the combiner has been fabricated and tested with a small signal. The combining efficiency is 98.5%. In this paper, we will validate the feasibility of the combiner from the design, simulation, and experiment.

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A band-projection formalism is developed for calculating the superfluid weight in two-dimensional multiorbital superconductors with an orbital-dependent pairing. It is discovered that, in this case, the band geometric superfluid stiffness tensor can be locally nonpositive definite in some regions of the Brillouin zone. When these regions are large enough or include nodal singularities, the total superfluid weight becomes nonpositive definite due to pairing fluctuations, resulting in the transition of a BCS state to a pair density wave (PDW). This geometric BCS-PDW transition is studied in the context of two-orbital superconductors, and proof of the existence of a geometric BCS-PDW transition in a generic topological flat band is established.

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Preparing composites from gricultural waste with biodegradable polymers is one of the strategies used to ensure the long-term sustainability of such materials. However, due to the differences in their chemical properties, biomass fillers often exhibit poor interfacial adhesion with polymer matrices. Inspired by mussel foot silk, this work focused on the surface modification of coffee grounds (CGs) using a combination of tannic acid (TA) and alkali treatment. CGs were used as a biomass filler to prepare polybutylene adipate terephthalate (PBAT)/CG composites. The modification of CGs was demonstrated by Fourier transform infrared spectroscopy (FTIR), the water contact angle, and scanning electron microscopy (SEM). The effect of CGs on the rheological, tensile, and thermal properties of the PBAT/CG composites was investigated. The results showed that the addition of CGs increased the complex viscosity, and the surface modification enhanced the matrix-filler adhesion. Compared with unmodified CG composites, the tensile strength and the elongation at break of the composite with TA-modified alkali-treated CGs increased by 47.0% and 53.6%, respectively. Although the addition of CGs slightly decreased the thermal stability of PBAT composites, this did not affect the melting processing of PBAT, which often occurs under 200 °C. This approach could provide a novel method for effectively using biomass waste, such as coffee grounds, as fillers for the preparation of polymer composites.

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In this article, a novel metal-organic framework, namely MIL-101(FeII), was firstly synthesized via a facile method. In the presence of H2O2, MIL-101(FeII) possesses excellent peroxidase-like activity toward the classical chromogenic substrate, N,N-Diethyl-p-phenylenediamine sulfate salt (DPD). The substitution of Fe2+ enhances the construction of Fe(II)-oxo nodes and accelerates electrons transfer between DPD and H2O2, thereby improving the peroxidase-mimicking catalytic activity of MIL-101(FeII) nanoenzyme. Additionally, DPD molecules could be adsorbed readily onto the surface of the nanoparticles due to the π-π interaction. The study of Michaelis constant indicates that the MIL-101(FeII) exhibits a higher affinity towards DPD (0.16 mM) in contrast to horseradish peroxidase (0.78 mM). In view of the impressive catalytic performance of MIL-101(FeII), two reliable monitoring platforms for the rapid detection of H2O2 and glucose were established with extremely low detection limits of 18.04 nM and 0.87 µM in the ranges of 40-5000 nM and 1.2-300 µM, respectively. The study of the catalytic mechanism indicates that DPD oxidation is attributed to the hydroxyl radical (·OH) produced from the decomposition of H2O2 catalyzed by MIL-101(FeII). Furthermore, the developed sensor indicates high selectivity and stability and can be effectively appropriate for the detection of H2O2 and glucose in real samples. This work not only provides a novel nanozyme with superior catalytic performance for biological analysis, but also broadens the application field of MIL-101(FeII) material.

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In this study, we fabricated high-performance polyethylene composites by constructing SiO2@silane coupling agent (γ-methylacryloxypropyl trimethoxysilane) and SiO2@polydopamine (PDA) double-layer structures on a magnesium oxysulfate whisker surface. In addition to realizing strong mechanical properties, the flame-retardant properties of the composites were effectively improved. Further increase in the initial crystallization temperature of the modified composites indicated that the dispersion of whisker in the matrix was improved. The drag effect of the modified whisker on the HDPE molecular chain was characterized by dynamic mechanical thermal analysis (DMTA) and the morphology of the impact-fractured surface was characterized by scanning electron microscopy (SEM); both confirmed the improved compatibility between the whisker and the matrix. The tensile strength of HDPE/MOSw@SiO2@KH570 and HDPE/MOSw@SiO2@PDA composites were 22.6% and 41.5% higher than that of the HDPE/MOSw composites, respectively. The impact strengths of the HDPE/MOSw@SiO2@KH570 and HDPE/MOSw@SiO2@PDA composites were 129% and 102% higher than that of the HDPE/MOSw composites, respectively. A stable carbon-silicate layer constructed by a SiO2@KH570 and SiO2@PDA double-layer structure delayed the combustion process. As a result, the limiting oxygen index (LOI) of HDPE/MOSw@SiO2@KH570 and HDPE/MOSw@SiO2@PDA composites increased from 22.5 to 22.9 and 23.5, respectively.

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Ceramifiable silicone rubber (SR) composites with excellent self-supporting properties and ceramifiable properties were prepared by incorporating silicate glass frits (SGFs) and sodium tripolyphosphate (STPP) into the SR. Ceramic residues were obtained by firing ceramifiable SR composites at 700, 850, and 1000 °C for 30 min. The bending angles of the composites were tested for evaluating the self-supporting property. To evaluate the ceramifiable properties of the ceramifiable SR composite, flexural strength, water absorption, and bulk density of its residues were tested. It was found that the addition of STPP improved the shape stability and the self-supporting property of the composites at high temperatures. The flexural strength of the ceramic residue of the composite with STPP firing above 850 °C is more than 5 MPa. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) analysis showed that the relative content of the crystalline phase was enhanced by about 25% due to the addition of STPP. Furthermore, a possible mechanism for the formation of the crystalline phase was proposed. Scanning elector microscope (SEM) and energy dispersive spectrometry (EDS) analysis demonstrated that with the temperature increase, the inter-infiltration between these melts became easier, which implies that the bulk density of the ceramic residue was improved.

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The slow redox rate of Fe(III)/Fe(II) couples is a rate-limiting step for Fenton-like performance of Fe-MOFs. In this study, a series of catalysts (MIL-101) with various p-phthalic acid/2-aminoterephthalic acid (H2BDC/NH2-H2BDC) molar ratios were prepared using a simple and mild chemical method and applied for catalyzed degradation of bisphenol A (BPA). Interestingly, the -NH2 modified MIL-101(Fe) can adjust Fe-Oxo node by increasing the electron density of Fe(III) in the presence of -NH2 group with high electron density, thus forming Fe(II) in situ in MOFs. Meanwhile, the -NH2 groups used as electron-donors can promote electron transfer, resulting in faster Fe(III)→Fe(II) half-reaction and active H2O2 to continuously generate •OH radical. The BPA degradation and rate constant of Fe-BDC-NH2/H2O2 system are 15.4-fold and 86.8-fold higher than that of Fe-BDC/H2O2 system, respectively. The density functional theory (DFT) calculations showed that Fe-BDC-NH2 possesses higher Fermi level energy (-4.88 eV) and lower activation energy barriers (0.32 eV) compared with Fe-BDC. Moreover, Fe-BDC-NH2 showed good reusability and stability. This work offers a highly efficient and stable MOFs-based Fenton-like catalyst to rapidly degrade organic pollutants over a wide pH range for potential applications in wastewater treatment.

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Fe/N-doped carbon magnetic nanocubes (Fe/N-C MNCs) were feasibly fabricated through in situ thermal transformations of Prussian blue nanocubes (PB NCs) in an inert atmosphere, and the resultant composite employed as the heterogeneous noble-metal-free catalyst possessed satisfactory catalytic performance in hydrogen peroxide activation. By examining the properties of Fe/N-C MNCs, we demonstrate for the first time that the catalyst could act in synergy with ultrasonic irradiation and accelerate the selectivity of the degradation reaction of dyes. The degradation efficiency of the organic positively charged dye (methylene blue) is significantly increased after ultrasonic irradiation addition, probably owing to charge matching between a positively charged dye and the Fe/N-C MNCs. Interestingly, organic pollution degradation mainly follows a non-radical pathway. Furthermore, singlet oxygen (1O2) is predominantly produced by Fe/N-C MNCs on H2O2 activation, and it is the contributor to catalytic degradation instead of hydroxyl and/or superoxide anion radicals. Moreover, the Fe/N-C MNCs exhibit excellent stability and reusability. These findings offer interesting insights into the potential application of functional noble-metal-free materials in catalysis and wastewater remediation under ultrasonic radiation.

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AIMS: Lung cancer is a key contributor to the cancer-related death throughout the world. FGF21 (fibroblast growth factor 21) has been found to regulate various pulmonary diseases, whereas, the role and mechanism of FGF21 in lung cancer remain unclear. The aim of this research was to explore the expression and function of FGF21 in lung cancer. MAIN METHODS: The mRNA and protein expression of FGF21 were analyzed through qRT-PCR and western blot, respectively. Cell proliferation, apoptosis and migration were analyzed by CCK-8 assay, flow cytometry and wound-healing assay, respectively. ROS, SOD, LDH and CK were examined with respective commercially kit. KEY FINDINGS: FGF21 level was increased in lung cancer tissue samples and cell lines at both mRNA and protein levels. Overexpressing FGF21 promoted cell growth and migration significantly. It also increased SOD and reduced ROS, LDH and CK contents. By contrast, down-regulated FGF21 presented the opposite effect on lung cancer cells. Furthermore, FGF21 may function as a tumor promotor by activating the SIRT1/PI3K/AKT signaling pathway in lung cancer. SIGNIFICANCE: This study demonstrated that FGF21 was a tumor promoter in lung cancer development, serving as a feasible therapeutic target in the treatment of lung cancer.

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Ceramifiable ethylene propylene diene monomer (EPDM) composites with fiber network structures were prepared by using aramid fiber (AF), ammonium polyphosphate (APP), and silicate glass frits (SGF). The effect of AF on the curing characteristic of the ceramifiable EPDM composites was studied. The morphology of AF in the composites system was observed by optical microscopy (OM) and scanning electron microscope (SEM). The effects of the observed AF network structures on the solvent resistance, mechanical properties, ablative resistance, self-supporting property, and ceramifiable properties of the composites were investigated. Results suggested that the existence of the AF network structure improved the vulcanization properties, solvent resistance, thermal stability, and ablative resistance of the EPDM composites. An excellent self-supporting property of the EPDM composites was obtained by combining the formation of the AF network and the formation of crystalline phases at higher temperature (above 600 °C). The thermal shrinkage performance of AF and the increased thermal stability of the EPDM composites improved the ceramifiable properties of the EPDM composites.

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A pair of Dirac points (analogous to a vortex-antivortex pair) associated with opposite topological numbers (with ±π Berry phases) can be merged together through parameter tuning and annihilated to gap the Dirac spectrum, offering a canonical example of a topological phase transition. Here, we report transport studies on thin films of BiSbTeSe_{2}, which is a 3D topological insulator that hosts spin-helical gapless (semimetallic) Dirac fermion surface states for sufficiently thick samples, with an observed resistivity close to h/4e^{2} at the charge neutral point. When the sample thickness is reduced to below ∼10 nm thick, we observe a transition from metallic to insulating behavior, consistent with the expectation that the Dirac cones from the top and bottom surfaces hybridize (analogous to a "merging" in the real space) to give a trivial gapped insulator. Furthermore, we observe that an in-plane magnetic field can drive the system again towards a metallic behavior, with a prominent negative magnetoresistance (up to ∼-95%) and a temperature-insensitive resistivity close to h/2e^{2} at the charge neutral point. The observation is consistent with a predicted effect of an in-plane magnetic field to reduce the hybridization gap (which, if small enough, may be smeared by disorder and give rise to a metallic behavior). A sufficiently strong magnetic field is predicted to restore and split again the Dirac points in the momentum space, inducing a distinct 2D topological semimetal phase with two single-fold Dirac cones of opposite spin-momentum windings.

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Iron-carbon (Fe/C) magnetic nanocubes were synthesized by direct pyrolysis of Prussian blue nanocubes under an inert gas atmosphere. They are shown to possess intrinsic peroxidase mimicking activity to catalyze the oxidation of peroxidase substrate N,N-diethyl-p-phenylenediamine sulfate salt to form a purple colored product in the presence of H2O2. The values for Km and Vmax are 74 µM and 46 nmol s-1, respectively. Steady-state kinetic analysis also indicates that the catalysis reaction follows a ping-pong mechanism. Based on these findings, an ultrasensitive colorimetric H2O2 assay was worked. Absorbance (best value measured at 550 nm) increases linearly in the 10 nM to 0.2 mM H2O2 concentration range, and the limit of detection is 1.5 nM. The method was also applied to the quantification of glucose, which is oxidized by glucose oxidase in the coexistence of H2O2. The response covers the 0.1 to 500 µM glucose concentration range, and the limit of detection is 16 nM. The method was applied to the determination of H2O2 in rainwater samples. The glucose assay was used to analyze serum samples, and satisfactory results were obtained. Other attractive features include good chemical activity, low cost, easy storage, and high catalytic efficiency. Graphical abstract Schematic presentation of converting Prussian blue nanoparticles into Fe/C magnetic nanocubes by a pyrolysis technique and the use of glucose oxidase and Fe/C magnetic nanocubes to establish a one-step spectrophotometric method for the determination of glucose and hydrogen peroxide.

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Fe2O3 is found to be a cost-effective and environmentally friendly catalyst for chemical looping generation of NH3 - a future fuel. The optimal Fe2O3 loading on nitrogen carriers, AIN, is 5 wt%. Fe2O3 can reduce the activation energy of the N-desorption step of AIN by 100 kJ mol-1 or ∼30%.

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A new, highly capable and dynamic aerogel adsorbent for CO2 capture was developed using a one-step sol-gel process along with solvent exchange and supercritical drying. The highest CO2 adsorption capacity in a 1% CO2 flow stream (5.55 mmol g(-1)) is much higher than other aerogel adsorbents obtained using a 10% or even higher CO2 gas mixture.

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A simple ultrasound-assisted co-precipitation method was developed to prepare magnetic Fe3O4/graphene oxide (Fe3O4/ GO) nanoparticles. The characterization with transmission electron microscope (TEM) indicated that the products possessed small particle size. The hysteresis loop of the dried Fe3O4/GO nanoparticles demonstrated that the sample had typical features of superparamagnetic material. Batch adsorption studies were carried out to investigate the effects of the initial pH of the solution, the dosage of adsorbent, the contact time and temperature on the adsorption of methylene blue. The results indicated that the composites prepared could be used over a broad pH range (pH 6-9). The adsorption process was very fast within the first 25 min and the equilibrium was reached at 180 min. The adsorption equilibrium and kinetics data fitted well with the Langmuir isotherm model and the pseudo-second-order kinetic model. The adsorption process was a spontaneous and endothermic process in nature. The composite exhibited fairly high adsorption capacity (196.5 mg.g-1) of methylene blue at 313 K. In addition, the magnetic composite could be effectively and simply separated by using an external magnetic field, and then regenerated by hydrogen peroxide and recycled for further use. The results indicated that the adsorbent had a potential in the application of the dye wastewater treatment.

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