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Herein, we report a regioselective cycloaddition strategy of N -aminopyridinium ylides with electron-deficient alkenes, in the presence of a hypervalent iodine reagent, PhI(OAc)2. A variety of multifunctionalized pyrazolo[1,5- a ]pyridine architectures were smoothly afforded by the reactions of pyridine-, quinoline-, and isoquinoline-based N -ylides with diverse alkenes with or without a halogen atom adjacent to the electron-withdrawing group (EWG) under facile conditions. [ABSTRACT FROM AUTHOR]

In this study, the wear characteristics of the die were tested and analyzed through compaction tests, and the distribution of wear depth along the direction toward the extrusion outlet was obtained. A discrete element method (DEM) model of the die's wear process was established. The results show that the severe wear area is located near the stop position of the compression rod, forming a plow-shaped wear area along the extrusion direction, accompanied by fatigue peeling. The wear depth gradually decreases towards the extrusion outlet. The DEM model partially reveals the occurrence of the wear phenomenon, but the particle motion speed deviates from the actual situation. The maximum compression force value range during the DEM compression stage is within the actual maximum compression force value range, and the relative error range of the average maximum compression force is less than 2%. By verifying the formula to calibrate the model, the calibrated model is compared with the actual mold wear, and the predicted value is close to the actual test result. The DEM can be used to explore the wear mechanism and predict the die's wear failure process, laying the foundation for optimizing die wear resistance design. [ABSTRACT FROM AUTHOR]

The crude protein (CP) content is an important determining factor for the quality of alfalfa, and its accurate and rapid evaluation is a challenge for the industry. A model was developed by combining Fourier transform infrared spectroscopy (FTIS) and chemometric analysis. Fourier spectra were collected in the range of 4000~400 cm−1. Adaptive iteratively reweighted penalized least squares (airPLS) and Savitzky–Golay (SG) were used for preprocessing the spectral data; competitive adaptive reweighted sampling (CARS) and the characteristic peaks of CP functional groups and moieties were used for feature selection; partial least squares regression (PLSR) and random forest regression (RFR) were used for quantitative prediction modelling. By comparing the combined prediction results of CP content, the predictive performance of airPLST-cars-PLSR-CV was the best, with an R P 2 of 0.99 and an RMSEP of 0.053, which is suitable for establishing a small-sample prediction model. The research results show that the combination of the PLSR model can achieve an accurate prediction of the crude protein content of alfalfa forage, which can provide a reliable and effective new detection method for the crude protein content of alfalfa forage. [ABSTRACT FROM AUTHOR]

This paper reviews the development and application of concentration gradient generators based on microfluidics. Generating solutions of varying concentrations is a frequent requirement in numerous experiments and applications. Traditional approaches involve the preparation of solutions with varying concentrations or the dilution of highly concentrated solutions. Nevertheless, these methods are intricate, time-consuming, and susceptible to errors. The advent of microfluidic concentration generators presents a novel concept for the realms of chemistry, biology, and medicine, allows biological or chemical experiments to be performed on a device with a measurement size of a few square centimeters or even smaller, thus greatly reducing the number of basic routine biological or chemical laboratory operations, such as sample preparation, reaction, separation, and analysis. In this review, we discuss the development and application of microfluidic concentration gradient generators through observation, introduce the development history of microfluidic concentration gradient generators and how they are used, summarize their wide range of applications in various fields, and discuss the possible future development direction of microfluidic concentration gradient generators. [ABSTRACT FROM AUTHOR]

In order to further improve the flame‐retardant properties of epoxy resins (EPs), two hydroxyl‐containing phospha‐phenanthrene derivatives, DOPO‐PHBA and DOPS‐PHBA, were prepared from the molecular structure design by using 9,10‐dihydro‐9‐oxa‐10‐phospha‐phenanthrene‐10‐oxide (DOPO), 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐sulfide (DOPS), and 4‐hydroxybenzaldehyde (PHBA) as the raw materials. These composites of DOPO‐PHBA/EP and DOPS‐PHBA/EP were prepared by melt blending. The results showed that UL‐94 V‐0 was achieved with an LOI of 31.9% when just 7.5% DOPS‐PHBA was added to EP, while a limited oxygen index of 35.2% was achieved with 10% DOPO‐PHBA/EP. Moreover, in comparison with 7.5% DOPO‐PHBA/EP, 7.5% DOPS‐PHBA/EP has the lower peak of heat release rates, total heat release values, and fire growth rate, demonstrating that the flame‐retardant DOPS‐PHBA is more effective at reducing heat release, enhancing the material's flame retardancy, and lessening the intensity of EP burning. The Thermogravimetric‐infraredspectrometry (TG‐IR) results showed that the phosphorus‐containing radicals generated by DOPS‐PHBA/EP pyrolysis trapped the free radicals, such as H˙, O˙, or HO˙, thus providing free radical quenching. Furthermore, combining the macro and micro Scanning electron microscopy (SEM) test results, DOPS‐PHBA/EP has a better char formation ability and a denser char layer, which can play a better role in heat and oxygen insulation. [ABSTRACT FROM AUTHOR]

The extraction of rare earth elements (REEs) from phosphogypsum (PG) is of great significance for the effective utilization of rare earth resources and enhancing the resource value of PG waste residues. This study used Aspergillus niger (A. niger) fungal culture filtrate as a leaching agent to investigate the behavior of extracting REEs from PG through direct and indirect contact methods. According to the ICP-MS results, direct leaching at a temperature of 30 °C, shaking speed of 150 rpm, and a solid–liquid ratio of 2:1, achieved an extraction rate of 74% for REEs, with the main elements being yttrium (Y), lanthanum (La), cerium (Ce), and neodymium (Nd). Under the same conditions, the extraction rate of REEs from phosphogypsum using an A. niger culture filtrate was 63.3% higher than that using the simulated organic acid-mixed solution prepared with the main organic acid components in the A. niger leachate. Moreover, the morphological changes observed in A. niger before and after leaching further suggest the direct involvement of A. niger's metabolic process in the extraction of REEs. When compared to using organic acids, A. niger culture filtrate exhibits higher leaching efficiency for extracting REEs from PG. Additionally, using A. niger culture filtrate is a more environmentally friendly method with the potential for industrial-scale applications than using inorganic acids for the leaching of REEs from PG. [ABSTRACT FROM AUTHOR]

Engineering efficient catalyst interfaces offers a constructive way to boost activity and stability in the field of water electrolysis. Here, unique core–shell FeCoS@CoMoP heterostructure nanoparticles are rationally fabricated on a porous Ni foam through hydrothermal and electrodeposition methods. The as-prepared electrocatalyst exhibits efficient pH-universal hydrogen evolution reaction (HER) activity along with a satisfactory alkaline oxygen evolution reaction (OER) performance, extremely small overpotentials, and Tafel values, achieving prominent durability and stability. A series of structural characterizations help identify the reactive centers during the catalytic procedure and the tight interfacial interaction between the shell and core materials. Density functional theory (DFT) calculations reveal that the surface electrodeposition of CoMoP not only tunes the d-band center but also obviously decreases the Gibbs free energies in the HER/OER processes. It can be expected that the three-dimensional self-supported catalytic system will hold strong promise for effective water splitting, energy storage, and energy transformation devices. [ABSTRACT FROM AUTHOR]

The micromixer is an important prerequisite for realizing the function of the microfluidic chip system. Micromixers are mainly used in protein crystallization, biological reactions, drug delivery and other fields. Efficient micromixers enable fast bioreaction processes. In this paper, according to the principle of plane geometry, micromixers with three different structural obstacles, circular, equilateral triangle and square, are designed to study how to improve the mixing efficiency of the micromixer. In this paper, the influence of the obstacle structure on the mixing efficiency and pressure drop of the micromixer is analyzed. Through numerical simulation, the results show that when Re = 100, the mixing efficiency of the circular obstacle micromixer is up to 97.4%, and the pressure drop is 15,789.597 Pa. In addition, this paper analyzes that the use of cylindrical obstacles can make the fluid generate horizontal and vertical vortex flow, break the usual laminar flow, and significantly improve the mixing efficiency. [ABSTRACT FROM AUTHOR]

Viral myocarditis (VMC) is a common disease characterized by cardiac inflammation. AC-73, an inhibitor of CD147, disrupts the dimerization of CD147, which participates in the regulation of inflammation. To explore whether AC-73 could alleviate cardiac inflammation induced by CVB3, mice were injected intraperitoneally with AC-73 on the fourth day post-infection (dpi) and sacrificed on the seventh dpi. Pathological changes in the myocardium, T cell activation or differentiation, and expression of cytokines were analyzed using H&E staining, flow cytometry, fluorescence staining and multiplex immunoassay. The results showed that AC-73 alleviated cardiac pathological injury and downregulated the percentage of CD45+CD3+ T cells in the CVB3-infected mice. The administration of AC-73 reduced the percentage of activated CD4+ and CD8+ T cells (CD69+ and/or CD38+) in the spleen, while the percentage of CD4+ T cell subsets in the spleen was not changed in the CVB3-infected mice. In addition, the infiltration of activated T cells (CD69+) and macrophages (F4/80+) in the myocardium also decreased after the AC-73 treatment. The results also showed that AC-73 inhibited the release of many cytokines and chemokines in the plasma of the CVB3-infected mice. In conclusion, AC-73 mitigated CVB3-induced myocarditis by inhibiting the activation of T cells and the recruitment of immune cells to the heart. Thus, CD147 may be a therapeutic target for virus-induced cardiac inflammation. [ABSTRACT FROM AUTHOR]

The determination of plant growth regulators is of great importance for the quality monitoring of crops. In this work, 4-bromophenoxyacetic acid (4-BPA), one of the phenoxyacetic acids, was detected via the electrochemical method for the first time. A CeO2-decorated electrochemical exfoliated graphene (eGr) composite (CeO2/eGr) was constructed as the sensor for sensitive detection of 4-BPA due to the synergistic effect of the excellent catalytic active sites of CeO2 and good electron transference of the eGr. The developed CeO2/eGr sensor displayed a good linearity in a wide range from 0.3 to 150 μmol/L and the lowest detection limit of 0.06 μmol/L for 4-BPA detection. Electrochemical oxidation of 4-BPA follows a mix-controlled process on the CeO2/eGr electrode, which involves 2e in the transference process. This developed CeO2/eGr sensor has excellent repeatability with a relative standard deviation (RSD) of 2.35% in 10 continuous measurements. Moreover, the practical application of the sensor for 4-BPA detection in apple juice has recoveries in the range of 90–108%. This proposed CeO2/eGr sensor has great potential for detecting plant growth regulators in the agricultural industry. [ABSTRACT FROM AUTHOR]

Neonicotinoid insecticides are widely applied to improve the quality and yield of the crop. A sensitive and highly selective electrochemical sensor is required for monitoring their residues. In this paper, nano-structured cerium oxide and multiwall carbon nanotube composite (MWCNTs) were successfully constructed as an electrochemical sensor for nitenpyram (NIT) determination. The developed sensor has a broad linear range from 2 to 180 μM and a low detection limit of 0.72 μM (S/N = 3) for NIT detection under the optimal ratio of 1:1 between CeO2 and MWCNTs. The electrochemical oxidation process of NIT involves one proton and two electron. Moreover, this developed sensor has excellent reproducibility with a relative standard deviation (RSD) of 3.1% in six replicated measurements, and excellent stability with 92.95% current retention after 15 days. In addition, the modified electrode has a good sensitivity and stability for the measurement of NIT in actual samples, it has the recovery ranges of 90.60–97.78% for the determination of NIT in corn extraction and 90.06–114.4% for that of NIT in river water. The proposed CeO2/MWCNTs sensor exhibits a great potential for the quick detection of neonicotinoid insecticides in the agricultural industry. [ABSTRACT FROM AUTHOR]

As an alternative mechanism for cap‐dependent (m7GpppN) translation, internal ribosome entry site (IRES)‐dependent translation has been observed in the 5′ untranslated regions (5′ UTR) and coding regions of a number of viral and eukaryotic mRNAs. In this study, a series of 5′ terminal truncated structural protein genes that were fused with GFP was used to screen for potential IRESs, and IRESs were identified using a bicistronic luciferase vector or GFP expression vector possessing a hairpin structure. Our results revealed that a putative IRES was located between nt 1982 and 2281 in the VP3 coding region of the human rhinovirus 16 (HRV16) genomes. We also demonstrated that effective IRES‐initiated protein expression in vitro did not occur through splicing sites or cryptic promoters. We confirmed that thapsigargin (TG), an inducer of endoplasmic reticulum stress (ERS), facilitated increased IRES activity in a dose‐dependent manner. Additionally, the secondary structure of the IRES was predicted online using the RNAfold web server. Highlights: An IRES is found in the VP3 coding region of human rhinovirus 16.The IRES activity increased under endoplasmic reticulum stress. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the efficacy, safety, and prognostic factors of drug-eluting beads transarterial chemoembolization (DEB-TACE) in treating Chinese patients with liver cancer. A total of 367 liver cancer patients from 24 medical centers were consecutively enrolled in this multiple-center, prospective cohort study, including 275 hepatocellular carcinoma (HCC) cases, 37 intrahepatic cholangiocarcinoma (ICC) cases, and 55 secondary liver cancer cases. All the patients received CalliSpheres® DEB-TACE treatment. Treatment response, overall survival (OS), change of liver function, and adverse events (AEs) were assessed. DEB-TACE treatment achieved 19.9% complete response (CR) and 79.6% objective response rate (ORR), with mean OS of 384 days [95% confidence interval (CI): 375‐393 days]. CR and ORR were both higher in HCC patients compared with primary ICC patients and secondary liver cancer patients, while no difference was discovered in OS. Portal vein invasion was an independent risk factor for CR, while portal vein invasion, previous conventional TACE (cTACE) treatment, and abnormal blood creatinine (BCr) were independent risk factors for ORR. In addition, largest nodule size ≥5.0 cm, abnormal albumin (ALB), and abnormal total bilirubin (TBIL) independently correlated with unfavorable OS. Most liver function indexes were recovered to baseline levels at 1‐3 months after DEB-TACE. Common AEs were pain, fever, vomiting, and nausea; most of them were at mild grade. CalliSpheres® DEB-TACE is efficient and well tolerated in Chinese liver cancer patients. Portal vein invasion, previous cTACE treatment, largest nodule size, abnormal BCr, ALB, and TBIL correlate with worse prognosis independently. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the efficacy and safety of drug-eluting beads transarterial chemoembolization (DEB-TACE) treatment in Chinese hepatocellular carcinoma (HCC) patients and the prognostic factors for treatment response as well as survival. A total of 275 HCC patients were included in this prospective study. Treatment response was assessed by modified Response Evaluation Criteria in Solid Tumors (mRECIST), and progression-free survival (PFS) as well as overall survival (OS) were determined. Liver function and adverse events (AEs) were assessed before and after DEB-TACE operation. Complete response (CR), partial response (PR), and objective response rate (ORR) were 22.9%, 60.7%, and 83.6%, respectively. The mean PFS was 362 (95% CI: 34.9‐375) days, the 6-month PFS rate was 89.4 ± 2.1%, while the mean OS was 380 (95% CI: 370‐389) days, and the 6-month OS rate was 94.4 ± 1.7%. Multivariate logistic regression revealed that portal vein invasion (p = 0.011) was an independent predictor of worse clinical response. Portal vein invasion (p = 0.040), previous cTACE treatment (p = 0.030), as well as abnormal serum creatinine level (BCr) (p = 0.017) were independent factors that predicted worse ORR. In terms of survival, higher Barcelona Clinic Liver Cancer (BCLC) stage (p = 0.029) predicted for worse PFS, and abnormal albumin (ALB) (p = 0.011) and total serum bilirubin (TBIL) (p = 0.009) predicted for worse OS. The number of patients with abnormal albumin, total protein (TP), TBIL, alanine aminotransferase (ALT), and aspartate aminotransferase (AST) were augmented at 1 week posttreatment and were similar at 1‐3 months compared with baseline. The most common AEs were pain, fever, nausea, and vomiting, and no severe AEs were observed in this study. DEB-TACE was effective and tolerable in treating Chinese HCC patients, and portal vein invasion, previous cTACE treatment, abnormal BCr, ALB, and TBIL appear to be important factors that predict worse clinical outcome. [ABSTRACT FROM AUTHOR]

Objective: Our study was aimed to investigate the effect of cancer susceptibility candidate 2 (CASC2) on the proliferation, cell cycle, apoptosis, and metastasis of hepatocellular carcinoma (HCC) cells. Methods: CASC2 expression in tumor tissues and HCC cells was tested by quantitative real‐time polymerase chain reaction. After manipulating the expression of CASC2 in Hep3B and HepG2 cells, cells viability, including proliferation, apoptosis, cell‐cycle distribution, migration, and invasion were examined by colony formation assay, flow cytometry, wound‐healing assay, and transwell assay, respectively. The expression levels of proteins associated with the cell cycle and AKT/mTOR pathway were measured by the western blot. Stably transfected HepG2 cells were used to construct nude mice models, and tumorigenesis was evaluated to investigate the in vivo functions of CASC2 in HCC progression. Results: In tissues and cells of HCC, decreased CASC2 expressions were confirmed. Overexpression of CASC2 made cell cycle stagnated at G0/G1 phase and induced apoptosis. Meanwhile, the overexpression of CASC2 played significant roles in inhibiting the proliferation, migration, and invasion of HCC cells. Furthermore, In vivo experiment indicated that CASC2 restrained the growth of tumors. Conclusion: Our study suggested that CASC2 promoted cell apoptosis and suppressed cell growth and metastasis in HCC, indicating that CASC2 might be a useful biomarker of HCC. 1.We demonstrated that cancer susceptibility candidate 2 (CASC2) promoted cell apoptosis and suppressed cell viability and metastasis in hepatocellular carcinoma (HCC).2.This finding will improve the understanding of the mechanism involved in cancer progression and provide novel targets for the molecular treatment of HCC. [ABSTRACT FROM AUTHOR]