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A marine antifouling compound, N-octyl-2-hydroxybenzamide (OHBA), inspired by ceramide and paeonol molecules, was created. First, methyl salicylate was synthesized with salicylic acid and methanol, followed by n-octylamine through an ester-amine condensation reaction. Fourier transform infrared spectroscopy, nuclear magnetic resonance spectroscopy, and mass spectrometry confirmed the characteristic structure of the OHBA compound. Bioassays showed that OHBA inhibits the growth of typical marine fouling organisms, such as Vibrio azureus, Navicula subminuscula, Ulva pertusa, Mytilus edulis, and Amphibalanus amphitrite, indicating its broad-spectrum antifouling ability. A one-year marine real-sea test further demonstrated the excellent antifouling properties of OHBA. OHBA is also extremely biodegradable, with a half-life of 6.3 days, making it a less environmentally harmful replacement for widely-used heavy metal-containing antifoulants. [ABSTRACT FROM AUTHOR]

Herein, a new series of 2-chloro-N-(5-(2-oxoindolin-3-yl)-4H-pyrazol-3-yl) acetamide derivatives containing 1,3,4-thiadiazole (10a–i) and 4H-1,2,4-triazol-4-amine (11a–r) moiety was designed, synthesised as novel anticancer agents. The antiproliferative activity values indicated that compound 10 b stood as the most potent derivative with IC50 values of 12.0 nM and 10 nM against A549 and K562 cells, respectively. Mechanism investigation and docking studies of 10 b indicated that it possessed good apoptosis characteristic and dose-dependent growth arrest of A549 and K562 cells, blocked cell cycle into G2/M phase. Interestingly, 10 b suppressed the growth of A549 and K562 cells via modulation of EGFR and p53-MDM2 mediated pathway. [ABSTRACT FROM AUTHOR]

Rice bacterial leaf blight is a destructive bacterial disease caused by Xanthomonas oryzae pv. oryzae (Xoo) that seriously threatens crop yields and their associated economic benefits. In this study, a series of improved dissolubility 7-aliphatic amine tryptanthrin derivatives was designed and synthesized, and their potency in antibacterial applications was investigated. Notably, compound 6e exhibited excellent activity against Xoo, with an EC50 value of 2.55 μg/mL, compared with the positive control bismerthiazol (EC50 = 35.0 μg/mL) and thiodiazole copper (EC50 = 79.4 μg/mL). In vivo assays demonstrated that 6e exhibited a significant protective effect on rice leaves. After exposure, the morphology of the bacteria was partially atrophied by SEM. Furthermore, 6e increased the accumulation of intracellular reactive oxygen species, causing cell apoptosis and the formation of bacterial biofilms. All the results indicated that 6e could be a potential agrochemical bactericide for controlling phytopathogenic bacteria. [ABSTRACT FROM AUTHOR]

Featured Application: Based on experiments and mesoscopic numerical simulation methods, this paper analyzes the correlation between the meso-structural state and macro-mechanical properties, which is of great significance in the prediction of macro-mechanical properties of composite propellants, the analysis of meso-failure mechanisms, and the structural design of propellants. In this paper, first, the meso-debonding process of a GAP/CL20/AP composite solid propellant under uniaxial tension was analyzed using the advantages of the material point method (MPM) and the finite element method (FEM) for the first time; then, the numerical simulation results were compared with the experiments. Based on the basic principle of modeling with the material point method, grains of different sizes were generated quickly and efficiently. Next, the grains were dispersed into particles, and the position information of the particles was mapped onto the background grid, so the background grids were used to determine the position of the grains. After that, the generated AP and CL20 grains were imported into the commercial software Abaqus through python scripting codes for numerical calculation. Based on macro-mechanical tests and a micro-numerical simulation, this paper studies the micro-internal mechanism that affects the macro-mechanical properties of composite solid propellants. Three interface parameters needed to be determined by parameter inversion, and the value of the objective interpolation function  min R  was 0.05078%. From a comparison, it was found that the numerical simulation results are in good agreement with the experimental results in the aspects of micro-crack cracking characteristics and the nominal stress–strain curve of propellants. After that, the influence of interface parameters on the stress–strain curve are discussed. The research in this paper has high scientific value and engineering application value and can provide important reference and guidance for the design of composite solid propellants and its mechanical property analyses, so as to solve the structural integrity problem of solid rocket motor charges. [ABSTRACT FROM AUTHOR]

In this study, a series of novel tryptanthrin derivatives were synthesized and their inhibitory activities against selected human cancer cell lines, namely, lung (A549), chronic myeloid leukemia (K562), prostate (PC3), and live (HepG2), were evaluated using a methyl thiazolyl tetrazolium colorimetric (MTT) assay. Among the tested compounds, compound C1 exhibited a promising inhibitory effect on the A549 cell line with an IC50 value of 0.55 ± 0.33 µM. The observation of the cell morphological result showed that treatment with C1 could significantly inhibit the migration of A549 cells through the cell migration assay. Moreover, after treatment with C1, the A549 cells exhibited a typical apoptotic morphology and obvious autophagy. In addition, the detection of apoptosis and the mitochondrial membrane potential indicated that C1 induced A549 cell apoptosis via modulating the levels of Bcl2 family members and disrupted the mitochondrial membrane potential. Compound C1 also suppressed the expression of cyclin D1 and increased the expression of p21 in the A549 cells, inducing cell cycle arrest in the G2/M phase in a dose dependent manner. The further mechanism study found that C1 markedly increased the transformation from LC3-I to LC3-II. Taken together, our results suggest that C1 is capable of inhibiting the proliferation of non-small cell lung cancer (NSCLC) cells, inducing cell apoptosis, and triggering autophagy. [ABSTRACT FROM AUTHOR]

To study the tensile properties of GAP/CL‐20/HMX (GCH) propellant, a new generation high energy solid propellant, uniaxial tensile test and dynamic mechanical analysis (DMA) test were performed at different temperatures (233.15–333.15 K) and strain rates (0.000476–0.9524 s−1). The experimental results show that, unlike Hydroxyl‐terminated Polybutadiene (HTPB) and Nitrate Ester Plasticized Polyether (NEPE) propellants, GCH propellant have special arc section in the initial tensile stage at room temperature and high temperature. This phenomenon may be caused by the stretching of the curled molecular chains. The variation of mechanical properties shows that the maximum tensile strength and initial elastic modulus increase with the decrease of temperature and the increase of strain rate. The variation of maximum elongation is complex, which increases with the increase of strain rate at room temperature and high temperature, and first increases then decreases with the increase of strain at low temperature. The constitutive model of the GCH propellant was established by introducing the chain extension and the debonding damage thresholds. Both of which show a linear double logarithmic increasing trend with the increase of strain rate at room and high temperature. The latter shows a linear double logarithmic decrease trend with the increase of strain rate at the low temperature. [ABSTRACT FROM AUTHOR]

Replacing natural aggregate (NA) with recycled aggregate (RA) has contributed to the trend of sustainable development in civil construction. With this background, improvements in the mechanical properties of recycled aggregate concrete (RAC) and the scientific design of the mixture ratio are attracting more concern in recent years. This paper is a review of the recent research, including the following aspects: the mixture design of RAC; the improved mechanical properties of recycled concrete with steel fibers; and the performance of the main components. In addition, the primary composition materials, properties, and calculation methods of the mixture ratio of RAC are summarized. The mechanical properties, durability and microscopic analysis of RAC are also discussed. The accurate calculation of mixture proportion can significantly facilitate the work of preparing a test mix of RAC. Through the mixture-ratio optimization and physical and chemical strengthening of RA, the mechanical properties of RAC can be improved to promote the wider application of this eco-friendly material. [ABSTRACT FROM AUTHOR]

Recently, great advances in polymerized small molecular acceptors (PSMAs) have boosted the power conversion efficiencies (PCEs) of all-polymer solar cells (all-PSCs) over the 17% milestone. However, significant research efforts have been mainly dedicated to designing narrow bandgap PSMAs by altering the building block and alkyl side chain. In this work, we report the design of novel PSMAs with wide bandgaps by incorporating a novel terminal unit without isomerization, 5-bromo-4,7-difluoro-1H-indene-1,3(2H)-dione (FFOBr). The resulting PSMAs exhibit high molar absorption coefficient over 105 M−1 cm−1, relatively wide bandgaps about 1.65 eV as well as high-lying lowest occupied molecular orbital (LUMO) energy levels of above −3.70 eV. When matching with the polymer donor JD40, both polymer acceptors can enable efficient all-PSCs with over 1.10 V open-circuit voltage (VOC) due to their high-lying LUMO energy level. Moreover, with a screened copolymerization spacer, the PFFO-Th-based blend film exhibits favorable morphology, more ordered crystallization, improved charge transport, and reduced recombination losses, which together contribute to the higher short-circuit current density and fill factor and thereby a high PCE of 10.8%. This value is one of the best with regard to PSMA-based all-polymer solar cells with VOC over 1.10 V in the reported literature. Our work shows that the terminal unit and linkage manipulation are effective strategies to develop high-performance PSMAs with controllable bandgaps. [ABSTRACT FROM AUTHOR]

The present study was conducted to evaluate the effect of Forsythiae Fructus aqueous extract (FAE) against cisplatin-induced emesis and to explore the antiemetic mechanism of FAE by focusing on NLRP3 inflammasome activation in a rat pica model. Our results showed that FAE significantly ameliorated cisplatin-induced acute and delayed pica in rats. Moreover, FAE improved the gastrointestinal histopathological injury and reduced the levels of serum ROS, IL-1β, and IL-18 in cisplatin-treated rats. In addition, the expressions of NLRP3, ASC, caspase-1, and IL-1β and the colocalization of the NLRP3 with ASC or caspase-1 in rat gastric antrum and ileum were also suppressed by FAE. Taken together, our findings indicate that FAE has a therapeutic effect against CINV, which may be related to its inhibition of the activation of NLRP3 inflammasome. [ABSTRACT FROM AUTHOR]

A polyacrylamide with capsaicin‐derived monomers (AM–MAA–AMPS–HMBA–SMA; AMAHS) was synthesized and investigated as a novel environment‐friendly polymer inhibitor for Q235 mild steel at 25°C in 1 M HCl solution. The inhibition efficiency was evaluated by weight loss measurements, electrochemical experiments, and surface investigation methods as well as by theoretical calculations. Experimental results indicated that the efficiency of AMAHS was up to 94.86% at the concentration of 2 g/L. Electrochemical tests and surface morphology analysis showed that AMAHS served as a mixed‐type corrosion inhibitor, which could be adsorbed and self‐assembled on the surface of mild steel forming a highly hydrophobic protective film (contact angle of 172°). Density functional theory calculations revealed that heteroatoms in AMAHS, such as O, N, S, are active sites in forming coordination bonds with surface iron atoms. In addition, hydrophobic groups played an important role in protecting the metal surfaces from corrosion media. [ABSTRACT FROM AUTHOR]

The reasons, prevention, and control of loess disaster are of great concern in practice. In recent years, Xi'an city, China, has taken the leadership in large-scale construction of subway lines in the loess strata. To study the structural response of the tunnel in loess region under local hydrodynamic environment, an experimental testing in 1g as well as a numerical simulation were performed, in which the achieved results were verified and were found to be in good agreement. Furthermore, the results showed that when the water outlet point is above the lining, the overall stress of the lining is "peanut shell," as the water pressure of the outlet point decreases, the tensile stress of the top and bottom of the lining increases, while the compressive stress on both sides decreases; the channel form of the flow to the lining changes with the variation of the position of the water outlet point. It is worth mentioning that in the process of water gushing, the closer to the water source, the greater surface subsidence is, and there is a positive correlation between water pressure and surface subsidence. This study is of significant benchmark for the construction, maintenance, and prevention of tunnel in loess strata under the influence of water environment. [ABSTRACT FROM AUTHOR]

The capsaicin in hot peppers is an important biological active substance that is widely used in food and medicine. In this work, six capsaicin derivatives such as N‐(4‐Hydroxy‐3‐acetophenone benzyl)acrylamide (A), 2‐hydroxy‐3‐(octyloxy)phenyl‐5‐acrylamidemethylbenzene phenyl methanone (B), N‐(2,5‐dihydroxybenzene)acetamide (C), N‐(5‐acetamidemethyl benzene‐2,4‐dihydroxybenzene)acetamide (D), 4‐acetamideme thylbenzene‐2‐benzylphenol (E), and N‐(2‐methyl‐4‐hydroxy‐5‐methylthiobenzene)acetamide (F) were synthesized via the Friedel–Crafts (F–C) alkylation reaction and were characterized using IR, 1H NMR, and HRMS. The antioxidant activity of compounds was evaluated using the reducing power and DPPH radical (DPPH·) scavenging assays, and Vitamin C (Vc) was used as a control. The antibacterial activity was tested using minimum inhibition concentration (MIC) and antibacterial rate assays, and Escherichia coli and Staphylococcus aureus were used as the tested strain. The results showed that all six capsaicin derivatives had certain antioxidant and antibacterial activities, and the activities increased with increasing mass concentration. The best properties were obtained for compounds C and F; the antioxidant activity of compound C was similar to Vc and the MIC of compound F was 0.0313 mg/ml, its antibacterial rate was greater than 99% at 3 mg/ml. Practical applications: As a vegetable, peppers can be eaten fresh or processed to other forms such as pepper powder or pepper jam, and it is very popular because of its long history, unique flavor, and special functions. Our current study shows that capsaicin derivatives have good antioxidant and antibacterial activities, and therefore, the present study of capsaicin derivatives with good activity provides a good foundation for future applications in natural food additives and medicine. [ABSTRACT FROM AUTHOR]

The factors that control arsenic (As) mobilization by dissimilatory iron reduction (DIR) are complicated. The association between As mobilization and extracellular polymeric substance (EPS) of dissimilatory iron reducing bacteria (DIRB) remained unclear. In this study, three DIRB were isolated from high arsenic groundwater to understand the effects of EPS on As mobilization. In the laboratory settings, strain Klebsiella oxytoca IR-ZA released As into aqueous phase from As-bearing ferrihydrite, while strain Shewanella putrefaciens IAR-S1 and S. xiamenensis IR-S2 re-sequestrated As by forming secondary minerals during ferrihydrite reduction. Characterization of EPS contents with Fourier Transform Infrared Spectroscopy and high-performance liquid chromatography suggested that mannan and succinic acid were the main different EPS contents of the DIRB. The biomineralization processes were tightly regulated by EPS compositions. Mannan secreted by IAR-S1 and IR-S2 promoted while succinic acid secreted by IR-ZA suppressed the biomineralization and As immobilization. Energy-dispersive X-ray Spectroscopy mapping indicated that As in the secondary minerals was wrapped with EPS. X-ray diffraction and room temperature Mössbauer spectroscopy showed these secondary minerals were vivianite and magnetite, respectively. The amount of As mobilized into aqueous phase was strongly affected by available anions (H 2 PO 4 − and HCO 3 −). Our results indicated that the EPS of DIRB significantly influenced As mobilization. Unlabelled Image • Three indigeous DIRB were found to release and re-sequestrate As, respectively. • EPS was the key factor that influenced As mobilization. • Mannan secreted by strains IAR-S1 and IR-S2 promoted the As immobilization. • Succinic acid by strain IR-ZA suppressed the As immobilization. [ABSTRACT FROM AUTHOR]

Background: Non-small-cell lung cancer is a prevalent malignancy associated with significant morbidity and mortality rates. Tryptanthrin and its derivatives have exhibited potent antitumor activity., Objective: This study aims to investigate the inhibitory effect of a novel synthesized tryptanthrin derivative D6 on proliferation and the possible mechanism of human non-small cell lung cancer cell lines (A549) in vitro., Methods: In this study, MTT assay, cell migration, colony formation assay, cell cycle analysis, cell apoptosis, JC- 1 staining assay, reactive oxygen species analysis, proteomics, western blotting, high content screening and absorption titrations analysis were performed., Results: We found that D6 inhibited both the proliferation and migration, induced cell cycle arrest in the G2/M phase, increased levels of ROS, decreased mitochondrial membrane potential, and promoted apoptosis in A549 cells. Further mechanistic studies found that D6 reduced EGFR expression in A549 cells and inhibited the EGFR pathway by decreasing phosphorylation levels of EGFR, Stat3, AKT and Erk1/2. Moreover, DNA damage induced by D6 involved an increase in p53/MDM2 ratio and concentration-dependent accumulation of micronuclei., Conclusion: D6 demonstrated significant antitumor activity against A549 cells by inhibiting the EGFR signaling pathway, inducing DNA damage, and subsequently leading to oxidative stress, apoptosis, and cell cycle arrest. Our findings suggest that D6 exhibits potential as an NSCLC drug, owing to its attributes such as antiproliferative activity and ability to induce apoptosis by attenuating the EGFR-mediated signaling pathway., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Xiao-Ban-Xia-Tang (XBXT), a traditional Chinese medicine formula, has been used for the treatment of emesis for nearly 2000 years, but its underlying mechanism is not yet fully clarified. The purpose of this study is to reveal the antiemetic mechanisms of XBXT by focusing on the NLRP3 inflammasome pathway in a chemotherapy-induced rat pica model. The pica model was generated by a single intraperitoneal injection of cisplatin in this study. Consumption of kaolin (a type of clay) and food and body weight were recorded every 24 hours. Cisplatin-induced increase in kaolin consumption (pica) was used to quantify chemotherapy-induced nausea and vomiting (CINV). Tissue from the ileum and antrum was stained with hematoxylin eosin (HE) to observe pathological changes. The levels of reactive oxygen species (ROS) and inflammatory cytokines, including IL-1 β and IL-18 in serum, were detected by ELISA. In addition, changes in the NLRP3 inflammasome activation in the ileum and antrum were investigated using western blot and immunofluorescence microscopy. The results showed that oral administration of XBXT and ondansetron inhibited acute and delayed pica and significantly protected against the gastrointestinal pathological injury induced by cisplatin. The levels of ROS, IL-1 β , and IL-18 in the serum of cisplatin-treated rats were also remarkably decreased by XBXT and ondansetron. Moreover, we found that XBXT can inhibit cisplatin-induced NLRP3 inflammasome activation. The present study indicates that the inhibition of the NLRP3 inflammasome activation might be one of the potential mechanisms for the therapeutic effects of XBXT against CINV., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2020 Qi Meng et al.)