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Porous Si 3 N 4 ceramics were fabricated via pressureless sintering employing ternary lithium oxides (LiScO 2 , LiYO 2 , LiYbO 2) derived from various Re 2 O 3 as sintering additives under nitrogen atmosphere at the temperature of 1400–1700 °C. The study studied how sintering temperatures andternary lithium oxide additives affect the phase, microstructure, and material properties of Si 3 N 4. The results show that as the amount of sintering aids increases, the bulk density of samples increases. At the same time, the apparent porosity diminishes, leading to enhancements in flexure strength and dielectric constant. The Si 3 N 4 -based porous ceramic sample containing 5 wt% LiYbO 2 sintered at 1600 °C exhibits a volumetric weight of 1.828 g/cm3, an apparent porosity of 35.14 %, an average flexure strength of 114.8 MPa, a dielectric constant of 3.95, a loss tangent of 5.457 × 10−3, and a low thermal conductivity of 8.241, offering insights into the preparation of radome materials. [ABSTRACT FROM AUTHOR]

Irinotecan (CPT-11) is used as chemotherapeutic drug for treatment of colorectal cancer. However, without satisfactory treatments, its gastrointestinal toxicities such as diarrhea and intestinal inflammation severely restrained its clinical application. Roots of Aucklandia lappa Decne. are used as traditional Chinese medicine to relieve gastrointestinal dysfunction and dehydrocostus lactone (DHL) is one of its main active components. Nevertheless, the efficacy and mechanism of DHL against intestinal mucositis remains unclear. The present study aimed to investigate the protective effects of DHL on CPT-11-induced intestinal mucositis and its underlying mechanisms. The protective effect of DHL was investigated in CPT-11-induced mice and lipopolysaccharide (LPS)+CPT-11 induced THP-1 macrophages. Body weight, diarrhea score, survival rate, colon length, and histopathological changes in mice colon and jejunum were analyzed to evaluate the protective effect of DHL in vivo. And DHL on reducing inflammatory response and regulating TLR4/NF‐κB/NLRP3 pathway in vivo and in vitro were explored. Moreover, DHL on the interaction between TLR4 and MD2 was investigated. And silencing TLR4 targeted by siRNA was performed to validate the mechanisms of DHL on regulating the inflammation. DHL prevented CPT-11-induced intestinal damage, represented by reducing weight loss, diarrhea score, mortality rate and the shortening of the colon. Histological analysis confirmed that DHL prevented intestinal epithelial injury and improved the intestinal barrier function in CPT-11 induced mice. Besides, DHL significantly downregulated the level of inflammatory cytokines by inhibiting TLR4/NF-κB/NLRP3 signaling pathway in CPT-11-induced mice and LPS+CPT-11-induced THP-1 macrophages. In addition, DHL blocked TLR4/MD2 complex formation. Molecular docking combined with SIP and DARTS assay showed that DHL could bind to TLR4/MD2 and occludes the hydrophobic pocket of MD2. Furthermore, Silencing TLR4 abrogated the effect of DHL on LPS+CPT-11 induced inflammatory response in THP-1 macrophages. Additionally, DHL ameliorate the CPT-11-induced intestinal mucositis without affecting the anti-tumor efficacy of CPT-11 in the tumor xenograft mice. This study found that DHL exhibited the anti-inflammatory effects in CPT-11-induced intestinal mucositis by inhibiting the formation of TLR4/MD2 complex and then regulation of NF-κB/NLRP3 signaling pathway. DHL is potentially served as a novel strategy of combined medication with CPT-11. [ABSTRACT FROM AUTHOR]

A micro-nano structure CaF 2 chemical conversion layer was prepared on fluoride-treated AZ31 alloy, then the composite fluoride conversion film (CaF 2 /MgF 2) was modified by stearic acid (SA) and fabricated a superhydrophobic surface. The fluoride-treated magnesium, fluoride conversion film and superhydrophobic coating were characterized by SEM, EDS, XRD and FTIR. The properties of coatings' adhesion and corrosion resistance were evaluated via tape test and electrochemical measurement. The cytocompatibility of the MgF 2 , CaF 2 and super-hydrophobic CaF 2 /SA surface was investigated with bone marrow-derived mesenchymal stem cells (BMSCs) by direct culture for 24 h. The results showed that the superhydrophobic fluoride conversion coating composed of inner MgF 2 layer and the outer CaF 2 /SA composite layer had an average water contact angle of 152°. SA infiltrated into the micro-nano structure CaF 2 layer and formed a strong adhesion with CaF 2 layer. Furthermore, the super-hydrophobic coating showed higher barrier properties and corrosion resistance compared with the fluoride conversion film and fluoride-treated AZ31 alloy. The BMSC adhesion test results demonstrated MgF 2 CaF 2 and CaF 2 /SA coatings were all nontoxic to BMSC. At the condition of in direct contact with cells, MgF 2 showed higher cell density and enhanced the BMSCs proliferation, while CaF 2 and CaF 2 /SA coating showed no statistically difference in cell density compared with glass reference but the CaF 2 and CaF 2 /SA coating were not conducive to BMSCs adhesion. [ABSTRACT FROM AUTHOR]

The polysaccharides obtained from the root of Ilex asprella, namely IAPS-1 and IAPS-2, with immunoregulatory activity were studied. Two polysaccharides were isolated and purified by Cellulose DEAE-52 and Sephadex columns. The structure of IAPS-1 was elucidated as 1,6-linked α- d -glucopyranosyl main chain with branch chain substituted at C-2 and/or C-4 position. For IAPS-2, the backbone is composed of 1, 4-linked α- d -glucose, galactose and rhamnose, and branched chains consists of arabinose, rhamnose and galacturonic acid, as confirmed by partial acid hydrolysis and NMR study. Further, the immunoregulatory activity of IAPS-1 and IAPS-2 was tested with the murine macrophages. Particularly, IAPS-2 polysaccharide can more effectively enhance the secretion of major inflammatory cytokines in macrophages, such as TNF-α, IL-1β, IL-12, compared with IAPS-1. [ABSTRACT FROM AUTHOR]

γ -Na 2 TiO 3 is a novel sodium titanate with TiO 5 trigonal bipyramids, and its properties have not been well characterized either experimentally or theoretically. In this study, γ -Na 2 TiO 3 was prepared from the reaction of NaOH and coarse TiO 2 particles, and analyzed by X-ray diffraction and vibrational spectroscopy. Meanwhile, the electronic structure, vibrational spectra, and thermodynamic properties of γ -Na 2 TiO 3 were obtained from first-principles calculations within density functional theory. The calculated lattice parameters after geometry optimization were close to the experimental values obtained from Rietveld refinement. The calculated band gap is 3.88 eV, lower than the experimental value of 4.06 eV from Tauc plot, and the extensive hybridization between Ti 3 d and O 2 p states forms covalent Ti–O bonds. γ- Na 2 TiO 3 has 33 active normal modes at k = 0, with 18 Raman acitive modes and 15 infrared active modes. The calculated Raman spectrum from LDA functional agrees well with the experimental one, and different vibrational modes were assigned. The strongest Raman peak at 803 cm −1 was assigned to the symmetric stretching of the shortest Ti–O bond in the TiO 5 unit. The calculated phonon dispersions indicate that γ- Na 2 TiO 3 is stable. The temperature dependence of its thermodynamic properties (i.e., heat capacity, entropy, and free energy) were calculated from the phonon density of states, and compared with relevant data from the experiments and thermodynamic softwares. [ABSTRACT FROM AUTHOR]

An electromechanical response of the chemically reduced graphene oxide (rGO) fiber is reported. The rGO fiber has a tensile strength of 159 MPa, and an electrical conductivity of 170 S/cm. When a current is applied, an immediate load-drop, up to 82% of the original loading, can be observed. Such a load-drop is partially reversible when the current is withdrawn. Higher current density (5–20 mA) and higher relative humidity (40%–80%) result in larger load changes. Joule heating induced dynamic absorption and desorption of water molecules, which further induce the rGO sheet sliding and elastic deformation are responsible for this actuation. [ABSTRACT FROM AUTHOR]

Solid waste tionite generated in the sulfate process for TiO 2 production is a secondary titanium resource with high silicon content. To recover titanium and remove silicon from the tionite, a process involving hydrothermal conversion, water washing, and acid leaching was proposed. To avoid Na 2 O loss, the formation of Na 2 TiSiO 5 by-product was prevented by adding CaO. XRD, ICP-OES and FT-IR were used to examine the transformation of the titanium and silicon. The optimum hydrothermal conditions are NaOH/tionite mass ratio of 4:1 and Ca/Si molar ratio of 1:1 in 45% NaOH solution at 240 °C for 1 h. Under these conditions, the titanium conversion was 97.3% with Na 2 TiO 3 as the main titanium phase, while most silicon was converted to Ca 2 SiO 4 , and katoite, and NaCaHSiO 4 , instead of Na 2 TiSiO 5 . About 97.5% of the Na 2 O was recovered after washing the hydrothermal products with water, and 93.1% of the silicon retained in the washed solution was removed by adding CaO. After leaching the washed products with 40% H 2 SO 4 solution at 60 °C, about 97% of the titanium was easily recovered, forming the titanyl sulfate solution that was employed for TiO 2 production. The Ca and Si components formed CaSO 4 and silica gel, which were then separated from the acid leaching solution. [ABSTRACT FROM AUTHOR]

Abstract: Significant progress has been made in recent years in research on wet spinning and hydrothermal synthesis of graphene fibers. In this paper, we report the relationship between the mechanical performance of graphene oxide (GO) fibers and their processing parameters in wet spinning. With super-aligned carbon nanotube (CNT) film wrapping, the specific strength and electrical conductivity of reduced GO (rGO) fibers were simultaneously enhanced by 22% and 49%, respectively. Thicker CNT film wrapping of the rGO fiber induces a core–sheath structure; the resulting interfacial debonding and slippage under fiber axial loading were examined. The findings of this study provide guidelines for optimization of high-performance graphene/CNT hybrid fibers. [Copyright &y& Elsevier]

The leach liquor of sodium-roasted vanadium slag in vanadium industry is an alkaline solution containing vanadium, sodium, chromium, and other impurities, and preparing high-purity vanadyl sulfate electrolyte (used in vanadium redox flow battery) directly from this solution is challenging but cost-effective. A novel process consisting of selective reduction–precipitation of chromium and solvent extraction of vanadium was proposed and optimized in this study. Approximately 90% of Cr(V I) in the solution was reduced to Cr(III) and precipitated after adding sodium sulfite at a pH of 5.77 and 25 °C, while V(V) remained in this process and needed a further reduction to V(IV) prior to extraction. More than 99.9% of V(IV) remained in the solution was extracted by two-stage extraction using the "P507 + TBP + kerosene" extractant system at a pH of 2.00 and an organic-to-aqueous phase ratio of 1.5:1. Sodium entrained in the organic phase was washed off through three-stage scrubbing. A high-purity vanadyl sulfate solution of 2.1 mol L−1 was prepared by two-stage stripping using 5.5 mol L−1 sulfuric acid. According to the slope analysis and infrared spectra, the extraction of V(IV) by P507 follow the cation exchange mechanism. This study provides a feasible way to remove chromium and recover vanadium in the form of vanadyl sulfate from the industrial leach liquor of sodium-roasted vanadium slag. • VOSO 4 solution was produced from leaching solution of sodium-roasted vanadium slag. • Chromium(VI) was removed by selective reduction–precipitation. • Vanadium was extracted by the "P507 + TBP + kerosene" extractant system. • Parameters of precipitation, extraction, scrubbing, and stripping were optimized. • Cation exchange mechanism was involved in the extraction of vanadium. [ABSTRACT FROM AUTHOR]

The seeds of Herpetospermum pedunculosum (Ser.) C.B. Clarke, a well-known Tibetan medicine in China, are rich in kinds of bioactive lignans. In this phytochemical investigation on H. pedunculosum , sixteen undescribed lignans, named as herpedulins A - P together with 24 known ones were isolated from the ethyl acetate extract of its seeds. Their structures including the absolute configurations were determined by HR MS, 1D and 2D NMR experiments, and comparison of their experimental ECD spectra with calculated ones or literature data. High content screening experiments revealed that 9 compounds could promote the expression of farnesoid X receptor in guggulsterone-induced human normal liver cells L02 cells significantly. Further molecular docking results demonstrated that herpedulin E, J and K exhibited best docking scores (9.70, 9.28 and 10.31, respectively). Hydrogen bonding and hydrophobic interactions might contribute to the main interaction of active compounds with FXR. [Display omitted] • Sixteen undescribed compounds were isolated from Herpetospermum pedunculosum. • The absolute configurations were determined via quantum chemical calculations. • 9 compounds could promote FXR expression in guggulsterone-induced L02 cells. • Molecular interactions of compounds with FXR were analyzed by in silico methods. [ABSTRACT FROM AUTHOR]

Abstract: Alumina matrix composites containing 5 and 10wt% of ZrO2 were sintered under 100MPa pressure by spark plasma sintering process. Alumina powder with an average particle size of 600nm and yttria-stabilized zirconia with 16at% of Y2O3 and with a particle size of 40nm were used as starting materials. The influence of ZrO2 content and sintering temperature on microstructures and mechanical properties of the composites were investigated. All samples could be fully densified at a temperature lower than 1400°C. The microstructure analysis indicated that the alumina grains had no significant growth (alumina size controlled in submicron level 0.66–0.79μm), indicating that the zirconia particles provided a hindering effect on the grain growth of alumina. Vickers hardness and fracture toughness of composites increased with increasing ZrO2 content, and the samples containing 10wt% of ZrO2 had the highest Vickers hardness of 18GPa (5kg load) and fracture toughness of 5.1MPam1/2. [Copyright &y& Elsevier]

Abstract: The preparation of ultrafine-grained alumina ceramics by the fast sintering technique Self-propagating High-temperature Synthesis plus Quick Pressing (SHS-QP) method and spark plasma sintering (SPS) technique was reported. The effects of different heating rates (SHS-QP-1600°C/min, SPS-200°C/min) on the preparation of ultrafine structure were compared. The densification and grain growth as a function of sintering time and temperature were discussed. Within a short sintering time (<3min), the full-dense alumina with ultrafine-grained structure was obtained by SHS-QP at 1550°C under 100MPa. By SPS, the sintering temperature was lower (1200°C) than that of SHS-QP. The differences in densification parameters were explained by analyzing the thermodynamics of sintering process. [Copyright &y& Elsevier]

Fast sintering processes offer promising new routes for the fabrication of bulk ceramics but it is not clear that the microstructural details and properties resulting from a very short, rapid densification procedure are the same in all respects as those resulting from traditional sintering. Here, not fully relaxed grains and their weak mechanical properties of as-prepared nanoscale alumina are described. It was found that low temperature annealing did not cause grain growth but allowed normal boundaries to develop. [Copyright &y& Elsevier]

Abstract: Experimental sintering studies on Al2O3 powder (200nm and 600nm) were done at a heating rate of 1600°C/min. The microstructural changes of specimens were examined and corresponding detailed data on the densification and grain size as a function of sintering time were presented. The grain-growth transition behavior during sintering was discussed. The results showed that the neck growth caused principally by surface diffusion could be negligible within 2min. With subsequent increases of sintering time, grain growth promoted by grain boundary and lattice diffusion occurred. [Copyright &y& Elsevier]

Abstract: Fine-grained alumina was obtained in 2min by a new densification method based on Self-propagating High-temperature Synthesis plus Quick Pressing (SHS/QP). The sample was densified to more than 99% of theoretical density under a large mechanical pressure (100MP) and a fast heating rate (1600°C/min). Compared with the alumina sample obtained by spark plasma sintering (SPS) at lower heating rates (100 or 500°C/min), almost no grain growth was found in the sample obtained in this work. The microstructure and mechanical properties were studied. Hardness value of 18.6±0.4GPa and fracture resistance value of 3.4±0.3MPam1/2 were measured for fine-grained alumina of this work. The densification mechanism was discussed. [Copyright &y& Elsevier]

Background: Cholestasis is characterized by accumulation of bile components in liver and systemic circulation. Restoration of bile acid homeostasis via activating farnesoid x receptor (FXR) is a promising strategy for the treatment of cholestasis. FXR-SHP (small heterodimer partner) axis plays an important role in maintaining bile acid homeostasis.Purpose: To investigate the anti-cholestasis effect of Dolomiaea souliei (Franch.) C.Shih (D. souliei) and clarify its underlying mechanism against α-naphthylisothiocyanate (ANIT) induced acute intrahepatic cholestasis.Methods: ANIT-induced Sprague-Dawley rats were employed to investigate the anti-cholestasis effect of D. souliei ethyl acetate extract (DSE). Ursodeoxycholic acid (UDCA) was used as positive control. Bile flow and blood biochemical parameters were measured. Liver histopathological examination was conducted via hematoxylin-eosin staining. Western blot analysis was carried out to evaluate the protein levels related to bile acids metabolism and inflammation. The interactions between FXR and costunolide or dehydrocostus lactone, were conducted by molecular docking experiments. The effect of costunolide and dehydrocostus lactone on aspartate aminotransferase (AST), alanine aminotransferase (ALT) levels and FXR expression were also evaluated using guggulsterone-induced L02 cells.Results: DSE could promote bile excretions and protect against ANIT-induced liver damage in cholestasis rats. Protein levels of FXR, SHP, Na+/taurocholate cotransporter (NTCP), bile salt export pump (BSEP), multidrug resistance-associated protein 2 (MRP2) were increased and the expressions of cholesterol 7α-hydroxylase (CYP7A1) and sterol 27-hydroxylase (CYP27A1) were decreased by DSE. Meanwhile, the anti-inflammatory factors, tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6) were also significantly increased, and the pro-inflammatory factor, interleukin-10 (IL-10), was significantly decreased in rats of DSE groups. Molecular docking revealed that costunolide and dehydrocostus lactone could be well docked into the FXR protein molecule, and hydrophobic interactions played the main function. Costunolide could reverse the increased AST and ALT levels and increase the FXR expression in guggulsterone-induced L02 cells.Conclusion: DSE had an anti-cholestasis effect by activating FXR-SHP axis, inhibiting synthesis of bile acid, and increasing bile secretion, together with inflammatory response and improving liver injury. Costunolide may be the main active component. This study provided a potential therapeutic mechanism for D. souliei as an anti-cholestasis medicine in the treatment of cholestasis liver diseases. [ABSTRACT FROM AUTHOR]

Background: Pterocephalus hookeri (C. B. Clarke) Höeck, a Tibetan medicine widely used for treatment of rheumatoid arthritis, was recorded in Chinese Pharmacopoeia (2020 version) with slight toxicity. The liver injury was observed in mice with administration of n-butanol extract (BUE) in our previously study. However, the toxic components and the mechanism were still unrevealed.Purpose: The present study was aimed to isolate and structural elucidate of the toxic compound pterocephin A (PA), as well as evaluate its liver toxicity and investigate its mechanism.Methods: PA was isolated from the BUE of P. hookeri. Its structure was determined by analysis of HRMS, NMR and ECD data. L-02 cellular viability, LDH, ALT, AST, ROS, intracellular Ca2+ and the fluidity of cell membrane were assessed by multifunctional microplate reader. The PI staining, cell membrane permeability assessment, and mitochondrial fluorescence staining analysis were determined through the fluorescence microscope. Liver samples for mice were assessed by pathological and immunohistochemistry analysis. Expression levels of indicated proteins were measured by western blotting assays.Results: PA was determined as a previously undescribed oleanolane-type triterpenoid saponin. In vitro study revealed PA significantly induced hepatotoxicity by inhibition of L-02 cell growth, abnormally elevation of ALT and AST. Mechanically, PA induced the damage of cell membrane, fragmentation of mitochondria, and subsequently increase of intracellular Ca2+ and ROS levels, which trigged by necroptosis with the activation of RIP1 and NF-κB signaling pathways. In vivo study confirmed PA could induce liver injury in mice with observation of the body weight loss, increasing of serum ALT and AST, and the histopathological changes in liver tissues.Conclusion: Our present study indicated that PA was an undescribed toxic constituent in P. hookeri to induce liver injury in mice by activation of necroptosis and inflammation. And the findings are of great significance for the clinical use safely of this herb. [ABSTRACT FROM AUTHOR]

Silica-aluminum borates (SiO 2 -R 2 O 3 -R 2 O-RO-ZrO 2 system) with La 2 O 3 replacing BaO were preparing using the conventional melt quenching process. The impact of substituting BaO with La 2 O 3 on the glass structure was examined using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and Raman. The density, thermal properties, alkali resistance and dielectric properties of the glasses were measured and compared using Archimedes, Differential Scanning Circuit (DSC), Thermal Expansion Calorimetry (TEC), Weight Reduction and Impedance Spectroscopy. The viscosity of the glass system was calculated from the thermal properties and discussed in comparison with the wetting angle at 1000 °C. The results showed that the glass does not undergo precipitation. With the increase of La 2 O 3 to BaO substitution, the Q4 in the glass network structure transforms to Q0+Q1 and Q2, causing depolymeriation of the glass structure. This results in an increase in the density of the glass, as well as an increase and subsequent decrease in the thermal expansion coefficient. Additionally, the glass transition temperature and glass softening temperature decrease and then increase, which was due to the high field strength of La3+. When substituting 5 wt% of BaO with La 2 O 3 , The glass displayed the lowest dielectric constant and dielectric loss, along with the best alkali resistance. Viscosity calculations showed that the viscosity gradually increases at 1000 °C with the increase of La 2 O 3 substitution, which was consistent with the wettability results. The glass components in the 0-5 wt% weight range all satisfy the iron-sealed glass wetting angle requirements. [ABSTRACT FROM AUTHOR]

In order to explore the effects of BN addition on the mechanical and electrical properties of oxidative sintered Si 3 N 4 -BN composites, Si 3 N 4 -BN composites with BN powder dosage of 0-40 wt% are prepared by molding technology, and the effects of different BN contents on the phase, morphology, bulk density, porosity, flexural strength at room temperature, dielectric constant and dielectr loss of the composite system are studied. With the increase of BN content, at different temperatures, the oxidation product B 2 O 3 of BN and the oxidation product SiO 2 of Si 3 N 4 firstly react on the surface to form B 2 O 3 –SiO 2 glass phase, which densify the surface and affects the oxidation degree of internal grains. At the same time, a small amount of B 2 O 3 escaping from the surface, so that the open pores of the composites decrease firstly and then increase slightly, and the dielectric constant increases firstly and then decreases. The results show that when the amount of BN micronized powder is 10 wt%, the oxidation sintered Si 3 N 4 -BN composite material at 1500 °C have pores that retain the sheet structure of boron nitride, and the amorphous material flows to fill the pores, so it have high volume density (1.85 g/cm3), low porosity (apparent porosity 6.37%), and high mechanical properties (flexural strength 127.86Mpa), higher dielectric constant (3.94) and lower dielectr loss (4.0 × 10−4). [ABSTRACT FROM AUTHOR]

Abstract Fe 3 O 4 @C nano-adsorption was prepared by a simple one-step solvothermal synthesis method using Fe (NO 3) 3 、cyclodextrin as raw materials, meanwhile urea as an alkali source. The obtained samples were characterized by X-ray diffraction, Raman spectroscopy, transmission electron microscopy, scanning electron microscopy, and Brunauer-Emmett-Teller. The adsorption behavior of the Fe 3 O 4 @C toward Cr (VI) and Congo red was also studied. The core-shell structure Fe 3 O 4 @C exhibited large specific surface area of 112.91 m2 g−1. The prepared Fe 3 O 4 @C samples demonstrated typical ferromagnetic behavior and high removal capacity in removing the toxic Cr (VI) ions and organic pollutant CR from wastewater, together with facile magnetic separability and good recyclability. Equilibrium adsorption performance was conducted by using the Langmuir and Freundlich model and Freundlich model could simulate the adsorption process of Congo red and Cr (VI) better. The maximum adsorption capacity of Cr (VI) and Congo red was 33.35 mg g−1 and 262.72 mg g−1 by calculation. [ABSTRACT FROM AUTHOR]

The separation of praseodymium (Pr) and neodymium (Nd) is particularly challenging within the lanthanide series. A new strategy was developed for enhanced separation of Pr and Nd, using interfacial "push and pull" complexation induced by a kinetic effect. We found that the specific addition order of diethylenetriaminepentaacetic acid (DTPA) had an obvious influence on the separation behaviors of Pr/Nd. Notably, the separation coefficient was up to 3.25 with the addition of DTPA when the extraction process just started. This suggested that different complexation rates decided differences of extraction kinetics between Pr and Nd. It revealed differences in complexation rates of adjacent RE(III) with DTPA and dissociation rates of RE-DTPA complexes by stopped-flow spectrophotometry. The results indicated that the complexation rate constant of Nd3+ was higher than Pr3+. On contrary, the dissociation rate constant of Nd-DTPA was smaller than Pr-DTPA. Molecular dynamics (MD) simulations showed that the interfacial "push and pull" complexation effect led to differences in interfacial molecule arrangements and diffusion mass transfer rates near the interface. And thus, the separation of Pr/Nd can be enhanced. This research provides an efficient strategy for the purification of metals that are difficult to separate. [Display omitted] • Kinetic enhanced separation of Pr and Nd under "push and pull" complexation effect. • Competitive complexation of RE ions with [A336][NO 3 ] and DTPA. • Separation coefficients were affected significantly by the added order of DTPA. • Complexation kinetics were studied by stopped-flow spectrophotometry. • Study extraction kinetics via analysis of mean square distance based on MD. [ABSTRACT FROM AUTHOR]

0.9(Zn 0.9 Mg 0.1 )TiO 3 -0.1TiO 2 (ZMT-TiO 2 ) ceramics doped with BaO-B 2 O 3 -ZnO(BBZ) glass were prepared by conventional solid-state routes. The effects of BBZ glass on the phase evolution, microstructure, sintering mechanism and microwave dielectric properties have been investigated. The BBZ glass as a sintering agent can effectively reduce the sintering temperature of ZMT-TiO 2 ceramic below 1000 °C. The XRD patterns indicate that the ZMT-TiO 2 ceramic consisted of ZnTiO 3 , Zn 2 TiO 4 and TiO 2 phases. Added BBZ glass inhibit the decomposition of the ZnTiO 3 into Zn 2 TiO 4 and TiO 2 . In addition, SEM results showed that BBZ significantly improved the grain growth and densification, this is due to the fact that the BBZ glass liquid sintering mechanism. The sintering mechanism was analyzed through the wetting behavior and the activation energy(Ea). When added 3 wt% BBZ glass, the activation energy reduced from 614.79 KJ/mol to 417.49 KJ/mol. This result indicate that the BBZ glass can promote the sintering process. Typically, the ZMT-TiO 2 ceramic with 3 wt% BBZ sintered at 950 °C for 4 h has shown excellent microwave dielectric properties of ε r = 24.46, Q × f = 47500 GHz and τ f = -14.68 ppm/°C. [ABSTRACT FROM AUTHOR]

Thioredoxin1 (TRX1) is a key protein that regulates redox and is considered to be a key target for cancer therapy. Flavonoids have been proven to have good antioxidant and anticancer activities. This study aimed to investigate whether the flavonoid calycosin-7-glucoside (CG) exerts an anti-hepatocellular carcinoma (HCC) role by targeting TRX1. Different doses of CG were used to treat HCC cell lines Huh-7 and HepG2 to calculate the IC 50. On this basis, the effects of low, medium and high doses of CG on cell viability, apoptosis, oxidative stress and TRX1 expression of HCC cells were investigated in vitro. Also, HepG2 xenograft mice were used to evaluate the role of CG on HCC growth in vivo. The binding mode of CG and TRX1 was explored by molecular docking. Then si-TRX1 was used to further discover the effects of TRX1 on CG inhibition of HCC. Results found that CG dose-dependent decreased the proliferation activity of Huh-7 and HepG2 cells, induced apoptosis, significantly activated oxidative stress and inhibited TRX1 expression. In vivo experiments also showed that CG dose-dependent regulated oxidative stress and TRX1 expression, and promoted the expression of apoptotic proteins to inhibit HCC growth. Molecular docking confirmed that CG had a good binding effect with TRX1. Intervention with TRX1 significantly inhibited the proliferation of HCC cells, promoted apoptosis, and further promoted the effect of CG on the activity of HCC cells. In addition, CG significantly increased ROS production, reduced mitochondrial membrane potential, regulated the expression of Bax, Bcl-2 and cleaved-caspase-3, and activated mitochondria-mediated apoptosis. And si-TRX1 enhanced the effects of CG on mitochondrial function and apoptosis of HCC, suggesting that TRX1 participated in the inhibitory effect of CG on mitochondria-mediated apoptosis of HCC. In conclusion, CG exerts anti-HCC activity by targeting TRX1 to regulate oxidative stress and promote mitochondria-mediated apoptosis. • Calycosin-7-glucoside (CG) inhibited the proliferation and promoted apoptosis of HCC. • CG regulated oxidative stress and TRX1 expression in HCC. • CG had a good binding effect on TRX1 protein. • TRX1 participated in the inhibitory effect of CG on HCC. [ABSTRACT FROM AUTHOR]

Nine previously undescribed iridoids, ptehosides A-I (1 – 9), together with 12 known ones (10 – 21), were isolated from Pterocephalus hookeri (C.B. Clarke) Höeck. Their structures were elucidated using various spectroscopic methods including HR-ESI-MS, NMR, UV, IR and CD, etc. The cytotoxic activities of all isolates were evaluated using MTT method in three human cancer cell lines (Caco2, Huh-7, and SW982). As result, compound 9 exhibited substantial inhibitory activity on Caco2, Huh-7, and SW982 cells with IC 50 values of 1.17 ± 0.05, 1.15 ± 0.05 and 1.14 ± 0.04 μM, respectively. A preliminary mechanism study showed that 9 arrested the cell cycle of SW982 cells in the G0/G1 phase and induced apoptosis by upregulating Bax expression and downregulating Bcl-2 expression. Nine undescribed iridoids, together with twelve known ones were isolated from the whole plant of Pterocephalus hookeri. Among them, seven compounds showed significant cytotoxic activities against SW982 cells in vitro. Mechanically, ptehoside I (9) could arrest the cell-cycle in G0/G1 phase and induce apoptosis. [Display omitted] • Nine undescribed iridoids were isolated from the whole plant of Pterocephalus hookeri. • The stereochemistry was identified by acid hydrolysis, experimental and calculated ECD. • Ptehoside I (9) induced G0/G1 cell cycle arrest against SW982 cells in vitro. • 9 induced apoptosis and regulated the expression levels of Bax and Bcl-2 proteins in SW982 cells. [ABSTRACT FROM AUTHOR]

Si 3 N 4 –BaTiO 3 composite ceramics were prepared by hot pressing sintering. The effects of the amount of BaTiO 3 and annealing process on the microstructure, phase composition, dielectric properties and thermal conductivity of Si 3 N 4 composite ceramics were studied. With the increase of BaTiO 3 content, the density and the dielectric performance of the Si 3 N 4 -based composite ceramics are improved, while the thermal conductivity is reduced. The annealing treatment can not only inhibit the growth of β-Si 3 N 4 , refine the grain, reduce the content of intercrystalline glass phase and porosity, but also promote the precipitation of hexagonal barium titanate, all of which are beneficial to increase the dielectric constant and decrease the dielectric loss, but will slightly reduce the thermal conductivity of Si 3 N 4 –BaTiO 3 composite ceramic. The sample A2BT15 with 15% BaTiO 3 sintered at 1750 °C for 2 h and annealed at 1300 °C exhibited the maximum dielectric constant (ε = 10.57), the minimum dielectric loss (tanδ = 9×10-4), a high relative density (98.8%) and an acceptable thermal conductivity (14.5 W·m-1·K-1). Therefore, the selection of appropriate BaTiO 3 content and annealing process can regulate the dielectric property, thermal performance and mechanical property of Si 3 N 4 –BaTiO 3 composite ceramics in a certain range. [ABSTRACT FROM AUTHOR]

Abstract: Nanocrystalline Ba(Mg1/3Nb2/3)O3 (BMN) powders were successfully synthesized through a modified combustion synthesis method by using Ba(NO3)2, Mg(NO3)3·6H2O and Nb2O5 as starting materials. Gel precursor and calcined powders were characterized by thermogravimetric (TG), differential scanning calorimetry (DSC), X-ray powder diffraction (XRD) and transmission electron microscopy (TEM). The results demonstrate that pure perovskite Ba(Mg1/3Nb2/3)O3 powder formed at 800°C for 2h. And the crystallite size was about 40nm. The specimen sintered at 1550°C for 12h shows 96.3% of the theoretical density and gave the excellent microwave dielectric properties: ɛ r =31.3 and Qf =71,800GHz. [Copyright &y& Elsevier]