Search

Catalytic potential of carbon nanomaterials in peroxydisulfate (PDS) advanced oxidation systems for degradation of antibiotics remains poorly understood. This study revealed ordered mesoporous carbon (type CMK) acted as a superior catalyst for heterogeneous degradation of sulfadiazine (SDZ) in PDS system, with a first-order reaction kinetic constant (k) and total organic carbon (TOC) mineralization efficiency of 0.06 min‒1 and 59.67% ± 3.4% within 60 min, respectively. CMK catalyzed PDS system exhibited high degradation efficiencies of five other sulfonamides and three other types of antibiotics, verifying the broad-degradation capacity of antibiotics. Under neutral pH conditions, the optimal catalytic parameters were an initial SDZ concentration of 44.0 mg/L, CMK dosage of 0.07 g/L, and PDS dosage of 5.44 mmol/L, respectively. X-ray photoelectron spectroscopy and Raman spectrum analysis confirmed that the defect structure at edge of CMK and oxygen-containing functional groups on surface of CMK were major active sites, contributing to the high catalytic activity. Free radical quenching analysis revealed that both SO4•− and •OH were generated and participated in catalytic reaction. In addition, direct electron transfer by CMK to activate PDS also occurred, further promoting catalytic performance. Configuration of SDZ molecule was optimized using density functional theory, and the possible reaction sites in SDZ molecule were calculated using Fukui function. Combining ultra-high-performance liquid chromatography (UPLC)–mass spectrometry (MS)/MS analysis, three potential degradation pathways were proposed, including the direct removal of SO2 molecules, the 14S-17N fracture, and the 19C-20N and 19C-27N cleavage of the SDZ molecule. The study demonstrated that ordered mesoporous carbon could work as a feasible catalytic material for PDS advanced oxidation during removal of antibiotics from wastewater.

Recent evidence indicates that the abnormal differentiation of bone marrow‐derived mesenchymal stem cells (BMSCs) plays a pivotal role in the pathogenesis of osteoporosis. LncRNA SNHG1 has been found to be associated with the differentiation ability of BMSCs. In this study, we aimed to elucidate the role of lncRNA SNHG1 and its associated pathway on the differentiation of BMSCs in osteoporosis. Mice that underwent bilateral ovariectomy (OVX) were used as models of osteoporosis. Induced osteogenic or adipogenic differentiation was performed in mouse BMSCs. Compared to sham animals, lncRNA SNHG1 expression was upregulated in OVX mice. Also, the in vitro expression of SNHG1 was increased in adipogenic BMSCs but decreased in osteogenic BMSCs. Moreover, overexpression of SNHG1 enhanced the adipogenic capacity of BMSCs but inhibited their osteogenic capacity as determined by oil red O, alizarin red, and alkaline phosphatase staining, while silencing of SNHG1 led to the opposite results. LncRNA SNHG1 interacting with the RNA‐binding polypyrimidine tract‐binding protein 1 (PTBP1) promoted osteoprotegerin (Opg) methylation and suppressed Opg expression via mediating DNA methyltransferase (DNMT) 1. Furthermore, Opg was showed to regulate BMSC differentiation. Knockdown of SNHG1 decreased the expressions of adipogenic related genes but increased that of osteogenic related genes. However, the knockdown of Opg partially reversed those effects. In summary, lncRNA SNHG1 upregulated the expression of DNMT1 via interacting with PTBP1, resulting in Opg hypermethylation and decreased Opg expression, which in turn enhanced BMSC adipogenic differentiation and contributed to osteoporosis.

Background Prenatal stress (PS) can cause brain retardation, reduce the learning and memory ability of the offspring and significantly increase the incidence of depression in offspring. Paeoniflorin (PF), a kind of monoterpenoid glycoside, is one of the main active ingredients of Chinese Medicine Paeonia lactiflora Pall, has anti-inflammation and potential neuroprotective effects. However, few reports have shown that the neuroprotective effects of PF are exerted through ameliorating Glutamate toxicity in vivo and in vitro. Methods Here, we used a prenatal restraint stress model and Glu-induced excitotoxic neurotoxicity in SH-SY5Y cells to study the effects of PF. Results Our results showed that PF can ameliorate learning and memory impairments and increases the density of hippocampal neurons, typical Golgi-positive pyramidal cells, and neuronal Neurogranin (Ng) expression in PS rat offspring. Furthermore, PF can significantly up-regulate the decrease of Glu-induced SH-SY5Y cell viability. At the same time, PF can significantly reduce apoptosis, ROS, NO levels, and intracellular Ca2+ concentration, and significantly inhibit the increase of mitochondrial membrane potential. Besides, PF significantly increased the expression of Nrf2 and iNOS, decreased p-JNK/JNK, p-P38/P38, Bax/Bcl-2, active-caspase-3, and active-caspase-9. Conclusions Our results demonstrate that PF may be an effective treatment in preventing the development of PS-induced learning and memory impairment and have therapeutic potential in Glu-related neurological diseases.

Background We aimed to investigate the functions and underlying mechanism of lncRNA SNHG1 in bone differentiation and angiogenesis in the development of osteoporosis. Methods The differential gene or proteins expressions were measured by qPCR or western blot assays, respectively. The targeted relationships among molecular were confirmed through luciferase reporter, RIP and ChIP assays, respectively. Alkaline phosphatase (ALP), alizarin red S (ARS) and TRAP staining were performed to measure the osteoblast/osteoclast differentiation of BMSCs. The viability, migration and angiogenesis in BM-EPCs were validated by CCK-8, clone formation, transwell and tube formation assays, respectively. Western blot and immunofluorescence detected the cytosolic/nuclear localization of β-catenin. Ovariectomized (OVX) mice were established to confirm the findings in vitro. Results SNHG1 was enhanced and miR-181c-5p was decreased in serum and femoral tissue from OVX mice. SNHG1 directly inhibited miR-181c-5p to activate Wnt3a/β-catenin signaling by upregulating SFRP1. In addition, knockdown of SNHG1 promoted the osteogenic differentiation of BMSCs by increasing miR-181c-5p. In contrast, SNHG1 overexpression advanced the osteoclast differentiation of BMSCs and inhibited the angiogenesis of BM-EPCs, whereas these effects were all reversed by miR-181c-5p overexpression. In vivo experiments indicated that SNHG1 silencing alleviated osteoporosis through stimulating osteoblastogenesis and inhibiting osteoclastogenesis by modulating miR-181c-5p. Importantly, SNHG1 could be induced by SP1 in BMSCs. Conclusions Collectively, SP1-induced SNHG1 modulated SFRP1/Wnt/β-catenin signaling pathway via sponging miR-181c-5p, thereby inhibiting osteoblast differentiation and angiogenesis while promoting osteoclast formation. Further, SNHG1 silence might provide a potential treatment for osteoporosis. Graphic abstract

Electrochemical reduction in aqueous graphene oxide (GO) dispersion has emerged as an alternative route to producing a reduced GO (rGO) membrane on Au mesh. Under scanning electron microscopy, an interesting pattern formed by distinct differences was discovered from the deoxidization evolution. Scanning transmission X-ray microscopy shows the chemical composition coordination mixing of C–OH, C–O–C, HO–C O, and C O bonds at nanoscale resolution. The electrochemical reduction of C–OH, new bonding of C–O–C, and structure recovery of C C were obtained from GO transformation into the rGO membrane. In Kelvin probe force microscopy, the same pattern of rGO was also observed for the diversity of work functions ranging from 5.55 to 5.70 eV compared with the uniform distribution of GO of 5.78 eV. Density functional theory calculations predicted that the work function variation originated from the dependence of O atom number and functional group species. A high (low) diversity in work function values was ascribed to the C–O–C (HO–C O) bond even with increasing oxygen numbers, accounting for the peak variation. Controlling the work function holds great significance for photovoltaic behavior and band alignment in photoelectric devices. Thus, growing large-area rGO membranes offers a new route to obtaining membranes for applications requiring transparent materials.

Background: Extracellular electron transfers (EETs) are mainly involved in anaerobic respiration of quinone-respiring strains, which is applicable in many fields, such as microbiological fuel cell, bio-hydrogen production, anoxic denitrification, and bio-reduction of azo dyes. However, this kind of instinctive function of microbes was nonspecific and low efficient, which needed to be improved by addition of exogenous redox mediators (RMs). In this work, vanillin, syringaldehyde and p-hydroxybenzaldehyde, as the precursors of lignin, were functionally modified to RMs in effort to accelerate the bio-reduction azo dyes.Results: The results showed that the decolorization efficiency of MO motivated by modified vanillin were increased from 20% to 95% in less than 12 h. And the modified syringaldehyde was increased to 85% in 24h. According to GC-MS, the modified products of vanillin and syringaldehyde were mainly kinds of phenols, ketones and quinones. The RMs exhibited better electrochemical performances by CV measurement and the •OH radicals were found according to EPR. Under saline condition, the strain, in the presence of RMs, still exhibited a high and stable removal efficiency to MO.Conclusions: The novel RMs of biodegradation to azo dyes were prepared from lignin monomers. The RMs based on bio-materials are environment-friendly and have a remarkable effect in biodegradation of azo dyes. This work may provide a new route for the functional utilization of lignin-resource and a theoretical guidance for efficient biodegradation of azo dye wastewater.

Non-noble-metal-based electrocatalysts with superior oxygen reduction reaction (ORR) activity to platinum (Pt) are highly desirable but their fabrications are challenging and thus impeding their applications in metal-air batteries and fuel cells. Here, we report a facile molten salt assisted two-step pyrolysis strategy to construct carbon nanosheets matrix with uniformly dispersed Fe3N/Fe nanoparticles and abundant nitrogen-coordinated Fe single atom moieties (Fe@FeSA-N-C). Thermal exfoliation and etching effect of molten salt contribute to the formation of carbon nanosheets with high porosity, large surface area and abundant uniformly immobilized active sites. Aberration-corrected high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) image, X-ray absorption fine spectroscopy, and X-ray photoelectron spectroscopy indicate the generation of Fe (mainly Fe3N/Fe) and FeSA-N-C moieties, which account for the catalytic activity for ORR. Further study on modulating the crystal structure and composition of Fe3N/Fe nanoparticles reveals that proper chemical environment of Fe in Fe3N/Fe notably optimizes the ORR activity. Consequently, the presence of abundant FeSA-N-C moieties, and potential synergies of Fe3N/Fe nanoparticles and carbon shells, markedly promote the reaction kinetics. The as-developed Fe@FeSA-N-C-900 electrocatalyst displays superior ORR performance with a half-wave potential (E1/2) of 0.83 V versus reversible hydrogen electrode (RHE) and a diffusion limited current density of 5.6 mA cm−2. In addition, a rechargeable Zn-air battery device assembled by the Fe@FeSA-N-C-900 possesses remarkably stable performance with a small voltage gap without obvious voltage loss after 500 h of operation. The facile synthesis strategy for the high-performance composites represents another viable avenue to stable and low-cost electrocatalysts for ORR catalysis.

This article presents the 2-D numerical simulation results of the heavy-ion-induced leakage current degradation and single-event burnout (SEB) in the rated 1.2-kV silicon-carbide (SiC) super-junction (SJ) vertical diffusion metal-oxide-semiconductor (VDMOS). The employed simulation physics models were validated by the heavy-ion irradiation experiments of the commercially rated 1.2-kV SiC common VDMOS (C-VDMOS), which indicated a severe degeneration threshold of 500 V. The SiC common SJ VDMOS (C-SJ VDMOS) was proven to be sensitive to high-energy heavy-ion and represents comparative SEB performance compared with the SiC C-VDMOS. The robustness of the SiC SJ VDMOS with different single buffer layer (SBL) designs against a heavy-ion was simulated. It is found that the maximum temperature in the source metal/SiC interface and bottom of the structure could be compromised by the thickness of the buffer layer. As a result, the SiC SJ VDMOS with an optimal SBL exhibited a severe degeneration threshold of 800 V, which was a 60% increase compared to the SiC C-SJ VDMOS.

This study evaluated the safety, effectiveness, and feasibility of indocyanine green (ICG) tracing in guiding lymph-node (LN) dissection during laparoscopic D2 radical gastrectomy in patients with advanced gastric cancer (AGC) after neoadjuvant chemotherapy (NAC). We retrospectively analyzed data on 313 patients with clinical stage of cT1-4N0-3M0 who underwent laparoscopic radical gastrectomy after NAC between February 2010 and October 2020 from two hospitals in China. Grouped according to whether ICG was injected. For the ICG group (n = 102) and non-ICG group (n = 211), 1:1 propensity matching analysis was used. After matching, there was no significant difference in the general clinical pathological data between the two groups (ICG vs. non-ICG: 94 vs. 94). The average number of total LN dissections was significantly higher in the ICG group and lower LN non-compliance rate than in the non-ICG group. Subgroup analysis showed that among patients with LN and tumor did not shrink after NAC, the number of LN dissections was significantly more and LN non-compliance rate was lower in the ICG group than in the non-ICG group. Intraoperative blood loss was significantly lesser in the ICG group than in the non-ICG group, while the recovery and complications of the two groups were similar. For patients with poor NAC outcomes, ICG tracing can increase the number of LN dissections during laparoscopic radical gastrectomy, reduce the rate of LN non-compliance, and reduce intraoperative bleeding. Patients with AGC should routinely undergo ICG-guided laparoscopic radical gastrectomy.

Using the resorcinol-formaldehyde (RF) resin as carbon source, core-shell structured carbon-coated zinc oxide (ZnO@RFC) was synthesized by cetyltrimethylammonium bromide (CTAB) assisted in-situ polymerization followed with carbonization process. The results showed that the ZnO particles were uniformly coated by an amorphous carbon layer. The excellent structural stability and high electrochemical performance depend it to be designed into carbon shell with a tunable thickness up to 14.4 nm, resulting in the ZnO@RFC anode delivers initial discharge specific capacity of 543 mAh g−1 and optimized 125 cycle life with capacity retention of 97.5% for Zn/Ni secondary batteries. And the effects of the thickness of carbon shell on electrochemical performance, corrosion and hydrogen evolution reaction are fully investigated. The results indicate that the carbon shell not only improves the electrical conductivity between ZnO particles but also increases the stability of ZnO in electrolyte.

This brief presents 2-D numerical simulation results of a single-event burnout (SEB) in a 4H-silicon carbide (SiC) junction termination extension (JTE) termination structure of a power metal–oxide–semiconductor field-effect transistor (MOSFET). Using the rated 1.5-kV JTE termination structure, the most sensitive ion’s strike position to SEB is proved to be the edge of the P+/P− JTE region. Due to the severe punchthrough of the electric field, the source contact region is found to the most sensitive region to induce an SEB event. The SEB performance of the JTE termination structure with a single buffer layer or multilayer buffer is evaluated. The results show that the electric field distribution in four buffer layers (FBLs) is the most uniform to achieve the best SEB performance. Therefore, by adding an optimal FBL design to the termination region, the SEB threshold voltage can be increased to 1210 V instead of the common structure’s 250 V. The SEB safe operating area of the power MOSFET with an optimal FBL can increase more than three times compared with the common one.

The exact control of pore structure in carbon is desirable for offering a leap forward in a wide range of industrial applications, but the intractable hurdle relating to the anisotropic etching of carbon remains. Here, metal nano-drills are developed by which controllable pore size and adjustable hole depth can be rationally designed in both SP2- and SP2-SP3 hybridized carbon. A new catalytic drilling behavior is demonstrated, whereby the catalytic metal nanoparticles (Ru, Ni, Au, Pt, etc.) as drilling forces, accompanied by chemical etching, thermodynamically catalyze the decomposition of the surface barrier layer (K2CO3) and dynamically accelerate the anisotropic carbon etching rates. Subsequently, metal nano-drills open the enclosed internal spaces of activation carbonized microtubes (RCMT). Benefiting from the drilling structure featured by outer-inter connecting, RCMT exhibits 2.5 times higher Li2O2 accommodation capacity as the lithium-oxygen battery cathode and 2.8 times higher specific capacitance as the electric double-layer supercapacitor electrode than the carbonized microtube without the drilling process.

The colour quality assessment of reverse micelle-based (in octane or nonane medium) and conventional water-based dyed wool knitted fabric has been investigated using computer colour matching (CCM) approach. Both water-based and non-aqueous based dyeing methods exhibited no chromatic shift from the reflectance curves and established good linearity in the construction of calibration curves. The linearity of both calibration curves in terms of R2 value played a critical role in CCM. The colour yield obtained from reverse micellar dyed fabric samples was higher than the colour yield values from wool knitted fabrics dyed in water bath under different dye percentages. The CCM predicted concentrations were in good agreement to theoretical concentrations for both dyeing systems. To conclude, the results showed that reverse micellar dyeing in octane and nonane is capable of generating reliable colour recipes. The relative unlevelness indices (RUI) obtained from dyed wool knitted fabrics using reverse micellar approach reveal good to excellent levelness, which fulfills the requirements of the textile processing industry. TEM picture illustrated that reverse micelles are in nano-scale and this could enhance the dyeing effect of wool with reactive dyes.

In this study, a series of CuW/CeZr (denoted as xCu–yW–CZ hereafter) catalysts with both NO reduction and CO oxidation activity was synthesized by the co-impregnation method, aiming for simultaneous removal of NO and CO under oxygen-rich conditions. Characterizations including N2 adsorption and desorption, XRD, SEM, H2–TPR, and NH3–TPD were used to interpret the influence of WO3/CuO loading amount on catalytic activity. The results suggested that the addition of WO3 species increased the surface acidity of the catalyst while weakening its redox property. On the contrary, the addition of CuO species greatly enhanced the redox property of the catalyst while hardly changing its surface acidity. Notably, too high content CuO was prone to aggregate, which was unfavorable to catalytic activity. Consequently, 5Cu–10W–CZ with 5 wt% CuO and 10 wt% WO3 presented the most optimal catalytic activity because of high components dispersion, appropriate redox property, and surface acidity. A novel dual-function catalyst (CuW/CeO2–ZrO2) that can simultaneously catalyze NH3–SCR reaction and CO oxidation reaction, was synthesized by the co-impregnation method, aiming for simultaneous removal of NO and CO under oxygen-rich conditions.

Bowl-like nanostructures have attracted significant scientific and technological interest due to their favorable characteristics, such as high specific surface area, interconnected porous channels, and conductivity. However, tailored synthesis of bowl-like nanostructures with well-defined and uniform morphology is still a challenge. Herein, we report a versatile microemulsion assembly approach to prepare bowl-like nanostructures of three different materials: polymer, carbon, and platinum. To this end, polystyrene-block-poly(4vinylpyridine), PS-b-P4VP, block copolymer (BCP) microparticles with truncated-sphere shape and composed of stacks of parallel lamellae were used because those anisotropic microparticles play an important role in the design of bowl-like nanostructures. To form nanolamellae-within-microparticle morphology, a designed PS-b-P4VP/chloroform/CTAB microemulsion can be facilely obtained in the aqueous medium, where the morphology can be tailored by the interplay between macro-phase separations, BCP self-assembly, and interfacial energies of three phases in the presence of cetyltrimethylammonium bromide (CTAB). Finally, protonation or combination of cross-linking and pyrolysis of those truncated microparticles enables formation of polymer or carbon bowl-like nanostructures, respectively. Upon selective adsorption of Pt precursor salt ions with the pyridyl moieties followed by chemical reduction, subsequent calcination permits the synthesis of Pt bowl-like nanostructures. The microemulsion assembly approach opens up new ways to direct and template bowl-like nanostructures.

Lithium–sulphur batteries (LSBs) have been drawing rapidly increasing research attention because of the low cost and high theoretical capacity of sulphur. The applications of LSBs however are hampered by poor stability caused by the shuttle effects of lithium polysulphides (LiPS), poor conductivities of sulphur, and sluggish redox kinetics of LiPS. Here, an advantageous carved N-doped carbon nanobox structure triply functionalized with an FeCoNi trimetallic sulphide was developed as a high performance sulphur host for LSBs. The strong chemical interactions toward LiPS, half-metallic conductivities, and catalytic activities toward redox reactions of LiPS, enabled through functionalization with FeCoNi trimetallic sulphide, work together to resolve the critical issues of LSBs. Moreover, the carved N-doped carbon nanobox structure serves as a nanoreactor that helps retain LiPS at cathodes and offers a confined space for fast local redox reactions. The triply functionalized carved N-doped carbon nanoboxes (S-FeCoNi@C-CNB) lead to high performance LSBs, delivering a high capacity of 1238 mA h g−1 at 0.1C and maintaining a decent capacity of 655 mA h g−1 at 2C. The LSB exhibits excellent stability with a low capacity decay rate of 0.049% per cycle over 200 cycle operations at 1C, indicating the success of S-FeCoNi@C-CNB in suppressing the shuttle effect.

In this article, we investigate a 4H-SiC super- junction (SJ) MOSFET structure with a charge-imbalance doping-profile. According to our numerical simulations and comparisons with the conventional SiC VDMOS (C-VDMOS) and SiC SJ VDMOS (SJ-VDMOS) devices, the SJ-MOD structure offers a better trade-off between breakdown voltage (BV) and specific on-resistance ( $R_{on,sp}$ ). This leads to a high figure of merit ( $FOM=BV^{2}/R_{on,sp}$ ). In addition, due to the reduced electric field peak, the single-event burnout (SEB) of the device is significantly improved. The simulation results indicate that, using a LET value of 0.1 pC/ ${\mu }\text{m}$ and a 3000K global device temperature as the criterion for burning, the specific burnout-threshold voltage (using the optimal parameters of the proposed structure) exceeds that of the conventional structure. This indicates that the modified super-junction structure can indeed be used for different voltage-classes of the hardening SiC super-junction devices in the future.

A series of Cu–M/Ce0.8Zr0.2O2 (M = W, Nb, Cr and Mo) catalysts were synthesized by a co-impregnation method, aiming for the removal of NO and CO under oxygen-rich conditions. The activity experiments confirmed that Cu–M/Ce0.8Zr0.2O2 can simultaneously catalyze NH3-SCR reaction and CO oxidation reaction. Moreover, the difference in the catalytic activity of the Cu–M/Ce0.8Zr0.2O2 catalysts was investigated by a series of characterization techniques. The results suggested that the sequence of the ratio of Cu+/Cu on the surface of the catalysts was as follows: 10Cu10CrCZ > 10Cu10NbCZ > 10Cu10WCZ > 10Cu10MoCZ, and the redox performance of Cu–M/Ce0.8Zr0.2O2 was consistent with this sequence. Besides, the introduction of Cr did not significantly improve the surface acidity as compared with the introduction of W, Nb and Mo. Excellent NH3-SCR and CO oxidation activity depended on the appropriate surface acidity and redox performance. Thus, 10Cu10NbCZ showed the most excellent NH3-SCR and CO oxidation activity.

To combat severe soil desertification and sandstorms, the application of appropriate hydrogels to dry land/desert is a promising solution to advance sustainable water irrigation and retention, and even realize “intelligent” agriculture. To this end, the development of a hydrogel with stable monitoring functions and good mechanical properties to maintain the swelling capability under soil would be significant for “intelligent” agriculture applications. Herein, we report a robust bio-based hydrogel with excellent mechanical properties and unique fluorescence performance for monitoring irrigation applications. This bio-hydrogel possesses a double cross-linked interpenetrating supramolecular network in a bacterial cellulose (BC) porous matrix, which provides its high tensile/compressive strength (∼0.96/1.3 MPa) and excellent Young's modulus (∼6.67 MPa, vs. 0.01–1.0 MPa for reported agricultural hydrogels), as well as high strength retention after experiencing repeated swelling/drying and long-term compressive processes. Furthermore, the hydrogel displays unique non-traditional fluorescence with excellent stability even under extreme environmental conditions, such as high/low temperature and various organic solvents. The excellent fluorescence characteristics offer the potential to realize “visualized” agricultural irrigation. This study not only provides a distinctive bio-based hydrogel with broadened applications, but also presents new insight to promote the development of sustainable agriculture.

1,4-naphthoquinone and its derivatives have attracted widespread attention due to their multiple biological activities, such as induction of cancer cell apoptosis; however, most of these compounds have high cytotoxicity. In this study, in order to reduce their toxicity and increase their potential anti-tumor effects, we synthesized a novel 1,4-naphthoquinone derivative named 2-(naphthalene-2-thio)-5,8-dimethoxy-1,4-naphthoquinone (NTDMNQ), and investigated its apoptotic effects and underlying mechanism. Our results showed that NTDMNQ inhibited the viability of HepG2, Hep3B, and Huh7 human hepatocellular carcinoma (HCC) cells. It also increased the accumulation of cells in the G0/G1 phase of the cell cycle by increasing the expression levels of p-p53, p21 and p27, while decreasing the levels of Cyclin D1, Cyclin E, Cyclin-dependent kinase 2 (CDK2), CDK4, and CDK6. Inhibition of reactive oxygen species (ROS) by the ROS scavenger N-acetyl-L-cysteine (NAC) decreased apoptosis in NTDMNQ-treated cells. Western blot analysis showed that NTDMNQ increased the phosphorylation of p38 and c-Jun N-terminal kinase (JNK), and decreased the phosphorylation of extracellular signal-regulated kinase (ERK), AKT, and signal transducer and activator of transcription-3 (STAT3); these effects were blocked by NAC. Both the JNK inhibitor (SP600125) and p38 inhibitor (SB203580) reversed the phosphorylation of STAT3, and the ERK inhibitor (FR180204) and AKT inhibitor (LY294002) reduced the expression of STAT3. Taken together, these findings suggest that NTDMNQ induces apoptosis via ROS-mediated MAPK, AKT and STAT3 signaling pathways in HepG2 cells, and may be a potent anticancer agent.

In this study, a tellurium nanowire (NwTe) structure was synthesized as a template, and then a nanoscale zeolitic imidazolate framework 67 (Nano-Z67) was subsequently grown on it, denoted as Nano-Z67/NwTe. After pyrolyzed at a high temperature, the coordinated cobalt ion of Nano-Z67 and NwTe were transferred into the CoTe nanorods, which were encapsulated by a nitrogen-containing carbon nanowire (CN). The Nano-Z67/NwTe catalyzes the oxygen reduction reaction (ORR) with the electron-transfer number of 3.997 which is high than that of Pt/C with 3.995. The high ORR activity of Nano-Z67/NwTe attributed to the cobalt–nitrogen bond, carbon-nitrogen bond, and the NwTe-templated specific morphology, in which the CN serves as the conductive channel for electron transport. Remarkably, Nano-Z67/NwTe-750 not only demonstrates competitive performance compared with the Pt/C catalyst but also excellent stability.

Background Zeaxanthin, a carotenoid commonly found in plants, has a variety of biological functions including anti-cancer activity. Purpose This study aimed to investigate the potential mechanisms of zeaxanthin in human gastric cancer cells. Methods CCK-8 assay was used to examine the cytotoxic effect of zeaxanthin on human gastric cancer cells. Flow cytometry was used to analyse AGS cell cycle distribution and apoptosis status. Western blot analysis was used to detect the expression levels of cycle-related proteins (Cyclin A, Cyclin B1, CDK1/2, p21, and p27), apoptosis-related proteins (Bcl-2, Bad, caspase-3, PARP), MAPK, AKT, STAT3, and NF-κB. Results CCK-8 assay showed that zeaxanthin has obvious cytotoxic effects on 12 types of human gastric cancer cells, but no obvious toxic effect on normal cells. In addition, flow cytometry and Western blotting results showed that zeaxanthin induces apoptosis by reducing mitochondrial membrane potential; increasing Cytochrome C, Bax, cleaved-caspase-3 (cle-cas-3), and cleaved-PARP (cle-PARP) expression levels; and decreasing Bcl-2, pro-caspase-3 (pro-cas-3), and pro-PARP expression levels. Additionally, zeaxanthin caused cell cycle arrest at the G2/M phase by increasing the levels of p21 and p27 and reduced the levels of AKT, Cyclin A, Cyclin B1, and Cyclin-dependent kinase 1/2 (CDK1/2). Furthermore, after zeaxanthin treatment, the expression levels of reactive oxygen species (ROS), p-JNK, p-p38, and I-κB increased, and the expression levels of p-ERK, p-AKT, STAT3, and NF-κB decreased. However, the ROS scavenger N-acetylcysteine (NAC) and MAPK inhibitors inhibited zeaxanthin-induced apoptosis, and under the action of zeaxanthin, MAPK regulated NF-κB and STAT3, and reduced their protein expression levels. Conclusion Zeaxanthin has a potential effect against gastric cancer cells through the ROS-mediated MAPK, AKT, NF-κB, and STAT3 signaling pathways, and it is expected to become a new drug for the treatment of human gastric cancer.

An unconventional [2 + 3] cyclization of pyridinium ylides with 2-ylideneoxindoles has been developed for the facile construction of pharmacologically interesting polysubstituted 9H-pyrrolo[1,2-a]indol-9-ones (fluorazones). Mechanistic studies revealed that the reaction, which has a broad substrate scope, proceeds via intermolecular [1,4]-sulfonyl transfer. Moreover, biological evaluation showed that polysubstituted fluorazone 3ak potently inhibits indoleamine 2,3-dioxygenase 1, kynurenine production, and immunotolerance in tumors.

Revealing the active nature of oxide derived copper (OD-Cu) is of key importance to understand its remarkable catalytic performance during the cathodic CO2 reduction reaction (CO2RR) to produce valuable hydrocarbons. Using advanced spectroscopy, electron microscopy and electro active surface area characterization techniques, the electronic structure and the changes in the morphology/roughness of thermally oxidized copper thin films were revealed during CO2RR. For this purpose we developed an in situ cell for X-ray spectroscopy able to be operated accurately in the presence of gases or liquids to unite the role of the initial thermal oxide-phase and its active phase during the electrocatalytic reduction of CO2. It was found that the Cu(I) species formed during the thermal treatment are readily reduced to Cu0 during the CO2RR, whereas Cu(II) species are hardly reduced. In addition, Cu(II) oxide electrode dissolution was found to yield a porous/void structure, where the lack of electrical connection between isolated islands prohibits the CO2RR. Therefore, the active/stable phase for CO2RR is metallic copper, independent of its initial phase, with a significant change in its morphology upon its reduction yielding the formation of a rougher surface with higher number of under coordinated sites. Thus, the initial thermal oxidation of copper in air controls the reaction activity/selectivity due to the changes induced in electrode surface morphology/roughness and the presence of more under coordinated sites during the CO2RR.

The variation in the morphology and electronic structure of copper during the electroreduction of CO2 into valuable hydrocarbons and alcohols was revealed by combining in situ surface- and bulk-sensitive X-ray spectroscopies with electrochemical scanning electron microscopy. These experiments proved that the electrified interface surface and near-surface are dominated by reduced copper. The selectivity to the formation of the key C–C bond is enhanced at higher cathodic potentials as a consequence of increased copper metallicity. In addition, the reduction of the copper oxide electrode and oxygen loss in the lattice reconstructs the electrode to yield a rougher surface with more uncoordinated sites, which controls the dissociation barrier of water and CO2. Thus, according to these results, copper oxide species can only be stabilized kinetically under CO2 reduction reaction conditions.

Aluminum alloy 7050-T7451 is widely used in aeronautical large structural parts, and high speed cutting is often used in machining. The serrated chip is a critical state for chip formation in high speed cutting, and its formation and control mechanism are of great significance for actual machining. To study the chip formation of high speed cutting aluminum alloy 7050-T7451, the chips at different cutting speeds are obtained by high speed cutting experiments. Combined with microscopic observation, the chip shape evolution, chip localization fracture process and mechanism of different cutting speeds are analyzed. The morphological evolution of chips and the mechanism of chip breaking during high speed cutting of aluminum alloy are revealed. According to the machined surface of the chip root and the angle of the chip, the formation mechanism of the curl radius formed by the chip is analyzed. The critical cutting speed of plastic-brittle transformation of aluminum alloy 7050-T7451 in high speed cutting is obtained by studying the critical condition for strip-to-serration transition of chip morphology.

Covalent organic frameworks (COFs) is made by covalent bonding of light elements, such as carbon, oxygen, nitrogen, boron and hydrogen, which can be flexibly synthesized as a porous material with low density, high permanent porosity and controllable sizes. This mini-review outlined the current understandings of mechanisms to yield a chemically stable COF and the use of these COFs to be adsorbents for removing adsorbates from waters. The research and development need to apply the COFs as industrial adsorbetns was discussed.

The reaction of CO and O2 with submonolayer and multilayer CoOx films on Pt(111), to produce CO2, was investigated at room temperature in the mTorr pressure regime. Using operando ambient pressure X-ray photoelectron spectroscopy and high pressure scanning tunneling microscopy, as well as density functional theory calculations, we found that the presence of oxygen vacancies in partially oxidized CoOx films significantly enhances the CO oxidation activity to form CO2 upon exposure to mTorr pressures of CO at room temperature. In contrast, CoO films without O-vacancies are much less active for CO2 formation at RT, and CO only adsorbed in the form of carbonate species that are stable up to 260 °C. On submonolayer CoOx islands, the carbonates form preferentially at island edges, deactivating the edge sites for CO2 formation, even while the reaction proceeds inside the islands. These results provide a detailed understanding of CO oxidation pathways on systems where noble metals such as Pt interact with reducible oxides.

Proximity labeling (PL) and chemical cross-linking (XL) mass spectrometry are two powerful methods to dissect protein-protein interactions (PPIs) in cells. Although PL typically captures neighboring proteins within a range of 10-20 nm of a single bait protein, chemical XL defines direct protein-protein contacts within 1 nm in a systemic manner. Here, we develop a new method, named PL/XL-MS, to harness the advantages of both PL and XL. PL/XL-MS can enrich a subcellular compartment by PL and simultaneously identify PPIs of multiple proteins from XL data. We applied PL/XL-MS to dissect the human nuclear envelope interactome. PL/XL-MS successfully enriched the nuclear envelope proteins and identified most known inner nuclear membrane proteins. By searching the cross-linked peptides, we successfully observed 109 literature-curated PPIs of 14 nuclear envelope proteins. Based on the homoprotein XL data, we experimentally characterized a nuclear matrix protein, Matrin-3, and observed its preferential localization near the nuclear envelope. PL/XL-MS is a simple and general method for studying protein networks in a subproteome of interest.

Liquiritin (LIQ), a major constituent of Glycyrrhiza Radix, exhibits various pharmacological activities. In this study, to explore the potential anti-cancer effects and its underlying molecular mechanisms of LIQ in hepatocellular carcinoma (HCC) cells. LIQ significantly decreased viability and induced apoptosis in HepG2 cells by decreasing mitochondrial membrane potential and regulating Bcl-2 family proteins, cytochrome c, cle-caspase-3, and cle-PARP. The cell cycle analysis and western blot analysis revealed that LIQ induced G2/M phase arrest through increased expression of p21 and decreased levels of p27, cyclin B, and CDK1/2. The flow cytometry and western blot analysis also suggested that LIQ promoted the accumulation of ROS in HepG2 cells and up-regulated the phosphorylation expression levels of p38 kinase, c-Jun N-terminal kinase (JNK), and inhibitor of NF-κB (IκB-α); the phosphorylation levels of extracellular signal-regulated kinase (ERK), protein kinase B (AKT), signal transducer activator of transcription 3 (STAT3), and nuclear factor kappa B (NF-κB) were down-regulated. However, these effects were reversed by N-acetyl-L-cysteine (NAC), MAPK, and AKT inhibitors. The findings demonstrated that LIQ induced cell cycle arrest and apoptosis via the ROS-mediated MAPK/AKT/NF-κB signaling pathway in HepG2 cells, and the LIQ may serve as a potential therapeutic agent for the treatment of human HCC.

The black crystalline (aza)triangulene-based covalent organic framework TANG-COF was synthesized from its trinitro-TANG precursor via a one-pot, two-step reaction involving Pd-catalyzed hydrogenati...

The Polyhydroxyalkanoates (PHAs) are promising biodegradable materials exhibit similar thermal and mechanical properties as conventional plastics. However, the current production cost for PHAs is high and less application examples were found. In addition, the development of electrospun nanofibrous membrane has attracted more attention in recent years. This study aims to investigate the production of PHAs using dyeing wastewater as the carbon source to reduce the major operation cost and prepare Poly(3-hydroxybutyrate) (PHB)-based fibrous membrane with controlled surface microstructure through electrospinning technique. At the optimal Carbon to Nitrogen (C:N) ratio (100:1) by using dyeing wastewater, the reactor achieved 0.2562 g PHAs from unit mass of activated sludge and 0.0571 g PHAs from unit mass of COD consumed. By using industrial glucose as carbon source adjustment, 1.180 g polymer per 1 RMB could be synthesized at the optimal C:N ratio. As a feasible study, the industrial PHB was used for electropining. The influence of the process parameters (applied electric field, solution flow rate and polymer concentration) on the electrospun fiber microstructure was investigated and optimized in order to achieve smooth, bead-free fibers with diameter range of 1 - 10 mm. The morphological transition from bead-like microstructure to smooth fiber was investigated under control of three major process parameters: applied voltage increased from 9 kV to 20 kV, flow rate de-creased from 5 mL.hr-1 to 0.5 mL.hr-1 and polymer concentration increased from 9 wt% to 15 wt%. It was observed that well-defined fibrous film was achieved at applied electric field of 12 kV, flow rate of 1 mL.hr-1 and solution concentration of 14 wt%. The optimally processed electrospun fibers exhibited large area, continuous network with good distribution of fiber diameter distribution. Fibrous membrane fabricated by well-developed electrospinning technique has potentially offered application interest in the design of barrier coatings, adhesive interlayers for biological materials, and membranes for filtration of particulate matters and fiber-based food packaging materials.

Tuning the type and degree of heterometallic bonding in bimetallic catalysts is crucial to achieving optimal catalytic performance. In this study density functional theory (DFT) and X-ray absorption spectroscopy (XAS) were used to investigate the use of Ru-based bimetallic electrocatalysts for hydrogen oxidation/evolution reactions (HOR/HER) under alkaline conditions. The catalyst's hydrogen absorption and OH adsorption energies can both be tuned by altering the heterometallic bonding in bimetallic systems. DFT calculations were used in conjunction with a RuNi bimetallic system to optimize the hydrogen adsorption energy and weaken the OH adsorption energy. The degree of heterometallic bonding (i.e. the alloying extent) in the Ru2.3Ni1/C catalyst was experimentally confirmed by XAS analysis. Our findings indicate that tuning the hydrogen and OH adsorption energies on the RuNi bimetallic catalyst's surface leads to superior activity and stability in the alkaline HOR/HER compared to as-prepared Ru/C, commercial Pt/C and the reported catalysts. We showed that the oxophilic effect can be manipulated by altering heterometallic bonding and that both the hydrogen and OH adsorption energies are important determinants of the efficiency of low-cost HER/HOR catalysts in alkaline media.

Producing acetaldehyde, an important industrial chemical, by direct catalytic non-oxidative dehydrogenation of ethanol presents many advantages over current production methods, including generating hydrogen. However, a stable, active, and selective catalyst is currently unavailable. This work demonstrates that the high activity and selectivity of nanoporous (np) NiCu for this reaction can be stabilized by keeping the catalyst in a metastable (“kinetically trapped”) state. Using a combination of in situ ambient-pressure and ex situ X-ray photoelectron spectroscopy, environmental transmission electron microscopy, and density functional theory calculations enabled correlating changes in surface composition with the changes in activity and stability upon treatment of np NiCu with H2 and O2. Reduction of Ni-doped nanoporous Cu by H2 exposure enhanced the initial activity but led to complete catalyst deactivation within ∼40 hours. In contrast, O2 pretreatment of the same catalyst increased both activity and long-term stability, with only 15% activity loss over 40 hours. The stability of np NiCu as a catalyst inversely correlates with the amount of metallic Ni at the surface, which is enriched by the H2 pretreatment, while the O2 pretreatment leads to a kinetically trapped Ni2+ subsurface state. This work emphasizes that detailed understanding of pretreatment-induced nanoscale structural and compositional changes is necessary to optimize catalyst performance.

In this work, an improved 4H-SiC insulated gate bipolar transistor (IGBT), or CTH-IGBT, with a trench p-polySi/p-SiC heterojunction on the backside of the device is proposed to reduce the turn-off energy loss (Eoff) and turn-off time (Toff). The electrical properties of the proposed and contrast structures are all simulated using the ATLAS simulation software to research the working mechanism of this improved structure. For the static performance, the specific ON-resistance (Ron,sp) and the figure of merit (FOM = VBR2/Ron,sp) are not influenced much as compared to the traditional structure at the same breakdown voltage (VBR) of 12 kV. However, with a prominent electron current path formed by the heterojunction region of CTH-IGBT, a very available conduction path to discharge the electrons during turn-off process is proved in this article. The simulation results demonstrate that compared with the traditional structure, the turn-off energy loss of the CTH-IGBT is reduced by 76.4%, while the turn-off time is reduced by 85.0%.

Highlights • Multifrequency UAT significantly reduced the thawing time of frozen samples. • Multifrequency UAT could convert more acoustic energy into thermal energy. • Multifrequency UAT treated samples maintained better quality attributes. • Multifrequency UAT improved the physicochemical properties and structural characteristics., The effects of mono-, dual- and tri-frequency ultrasound-assisted thawing (UAT) on the physicochemical quality, water-holding capacity, moisture migration and distribution and myofibrillary structure of frozen large yellow croaker (Larimichthys crocea) were detected. The results indicated that multifrequency UAT treatment significantly increased the thawing rate, maintained the stability of myofibrils and reduced the lipid oxidation. The multifrequency UAT samples had better water-holding capacity (higher water-holding capacity values, lower thawing loss and cooking loss) and physicochemical quality (higher hardness, springiness, resilience, chewiness and lower total volatile basic nitrogen (TVB-N) values, thiobarbituric acid reactive substances (TBARS) values), higher immobilized water content, and lower free water content. Therefore, the results provide a further understanding of the quality stability of frozen large yellow croaker treated by the multifrequency UAT.

Background Human carboxylesterases (hCES) are key serine hydrolases responsible for the hydrolysis of a wide range of endogenous and xenobiotic esters. Although it has been reported that some ginsenosides can modulate the activities of various enzymes, the inhibitory effects of ginsenosides on hCES have not been well-investigated. Methods In this study, more than 20 ginsenosides were collected and their inhibitory effects on hCES1A and hCES2A were assayed using the highly specific fluorescent probe substrates for each isoenzyme. Molecular docking simulations were also performed to investigate the interactions between ginsenosides and hCES. Results Among all tested ginsenosides, Dammarenediol II (DM) and 20S-O-β-(d-glucosyl)-dammarenediol II (DMG) displayed potent inhibition against both hCES1A and hCES2A, while protopanaxadiol (PPD) and protopanaxatriol (PPT) exhibited strong inhibition on hCES2A and high selectivity over hCES1A. Introduction of O-glycosyl groups at the core skeleton decreased hCES inhibition activity, while the hydroxyl groups at different sites might also effect hCES inhibition. Inhibition kinetic analyses demonstrated that DM and DMG functioned as competitive inhibitors against hCES1A-mediated d-luciferin methyl ester (DME) hydrolysis. In contrast, DM, DMG, PPD and PPT inhibit hCES2A-mediated fluorescein diacetate (FD) hydrolysis via a mixed manner. Conclusion The structure–inhibition relationships of ginsenosides as hCES inhibitors was investigated for the first time. Our results revealed that DM and DMG were potent inhibitors against both hCES1A and hCES2A, while PPD and PPT were selective and strong inhibitors against hCES2A.

This study aims to examine ionoregulatory parameters during exercise and cortisol elevation in common carp fed different food rations. Fish subjected to two different feeding regimes (0.5 or 3.0% body mass (BM) daily) received no implant or an intraperitoneal cortisol implant (250 mg/kg BM) or sham, and were monitored over a 168-h post-implant (PI) period under resting, low aerobic swimming or exhaustive swimming conditions. Plasma osmolality was maintained at relatively stable levels without much influence of feeding, swimming or cortisol, especially in low feeding groups. Nevertheless, a transient hyponatremia was observed in all low feeding fish implanted with cortisol. The hyponatremia was more pronounced in fish swum to exhaustion but even in this group, Na+ levels returned to control levels as cortisol levels recovered (168 h-PI). Cortisol-implanted fish also had lower plasma Cl- levels, and this loss of plasma Cl- was more prominent in fish fed a high ration during exhaustive swimming (recovered at 168 h-PI). Cortisol stimulated branchial NKA and H+ ATPase activities, especially in high ration fish. In contrast, low ration fish upregulated kidney NKA and H+ ATPase activities when experiencing elevated levels of cortisol. In conclusion, low feeding fish experience an ionoregulatory disturbance in response to cortisol implantation especially when swum to exhaustion in contrast to high feeding fish.

π-Conjugated organic materials possess a wide range of tunable optoelectronic properties which are dictated by their molecular structure and supramolecular arrangement. While many efforts have been put into tuning the molecular structure to achieve the desired properties, rational supramolecular control remains a challenge. Here, we report a novel series of supramolecular materials formed by the co-assembly of weak π-electron donor (indolo[2,3-a]carbazole) and acceptor (aromatic o-quinones) molecules via complementary hydrogen bonding. The resulting polarization creates a drastic perturbation of the molecular energy levels, causing strong charge transfer in the weak donor-acceptor pairs. This leads to a significant lowering (up to 1.5 eV) of the band gaps, intense absorption in the near-IR region, very short π-stacking distances (≥3.15 Å), and strong ESR signals in the co-crystals. By varying the strength of the acceptor, the characteristics of the complexes can be tuned between intrinsic, gate-, or light-induced semiconductivity with a p-type or ambipolar transport mechanism.