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Dendritic fibrous nano silica (DFNS) was functionalized through the utilization of graphene oxide (GO) as a long-lasting anchoring agent. Consequently, the LaFeO3 nanoparticles were evenly spread out without clumping over the DFNS/GO. The supramolecular polymerized GO served the dual purpose of preventing the restacking of graphene sheets and functioned as a supplier of nitrogen to create active sites for the bonding of LaFeO3 nanoparticles. The nitrogen content above the extent of the GO films was modified by LaCl3·7 H2O and Fe(NO3)3·9H2O ions to synthesize LaFeO3 nanoparticles. The catalytic properties of DFNS/GO-LaFeO3 was observed in the reaction between CO2 and oxetane and epoxide, leading to the production of the corresponding polycarbonates. The results indicated that DFNS/GO-LaFeO3 significantly enhanced the efficiency of synthesizing poly(propylene carbonate) and poly(trimethylene carbonate) from carbon dioxide. This approach offers substantial benefits, including high economic efficiency. The union reaction of CO2 and highly substituted epoxides sourced from sustainable sources such as discarded vegetable oils and fatty acids resulted in the production of novel cyclic carbonates of bio-origin. This reaction occurred under gentle and solvent-free conditions using DFNS/GO-LaFeO3 as a catalyst. The DFNS/GO-LaFeO3 exhibited a high capacity for CO2 uptake with exceptionally rapid kinetics. The nanoplate morphology of DFNS/GO-LaFeO3 facilitated the formation of a satisfactory outer layer for carbon dioxide uptake at each metal site. Consequently, the nanoplate morphology of DFNS/GO-LaFeO3 ensured systematic carbon dioxide emission, guaranteeing a complete reaction with the entire sheet and enabling rapid CO2 adsorption kinetics.

High-strength bolt connection is a kind of main connection mode of prefabricated steel structures. Due to the insufficient fatigue performance of high-strength bolts, the degree of damage in the steel structure is very serious, so the fatigue performance research of high strength bolts cannot be ignored. The research object of the paper is M24 twisted-shear high-strength bolts in a steel structure buildings. Some special tests and results analysis on the normal fatigue performance were carried out, establishing the fatigue S-N curve of M24 twisted-shear high-strength bolts, revealing the fatigue failure mechanism of M24 torsion-shear high-strength bolts; obtaining the fatigue S-N curve equation; and estimating the fatigue life of high-strength bolts by using the Paris formula. In addition, by comparing the test data in this paper with the constant fatigue test data of high-strength bolts in the existing research literature, it can be seen how the strength grade of the bolts and the pretension force have an impact on the fatigue strength. It is further revealed that the M24 torsion-shear high-strength bolt with full pretension force has twice as long fatigue life than the other two types of bolts. By comparing the test results of M24 and M20 bolts under full pretension, it is known the relation between the fatigue strength of the bolts and diameter decreases. The research data and useful conclusions can provide scientific basis and theoretical reference for the anti-fatigue design of M24 torsion-shear high-strength bolt connection.

Composites of MnO2 nanosheet arrays vertically grown on the surface of vapor-grown carbon fibers (VGCFs) are fabricated by a low-temperature redox reaction between KMnO4 and the VGCFs. An assembled AC/0.5 M K2SO4/MnO2@VGCF electrochemical capacitor exhibits a higher specific capacitance, as well as a better rate capability, at a fast-current density compared to the capacitor built on hydrothermally prepared, standalone MnO2. Electrochemical tests revealed that VGCFs act as a conducting matrix, which effectively improves the conductivity of MnO2 nanosheets during cycling.

Neuroblastoma is the most common extracranial neuroendocrine tumor in childhood. Although many studies have tried to find effective treatments, there are still numerous limitations in current clinical targeted therapy. So, it is important to find new therapeutic targets and strategies from a new perspective. Our previous study reported that the androgen receptor (AR) promotes the growth of neuroblastoma in vitro and in vivo. Based on documentary investigation, we postulated that the AR–SCAP–SREBPs-CYP17/HMGCR axis may regulate cholesterol and androgens synthesis and form a positive enhancement loop promoting NB progression. Clinical samples and Oncomine database analysis proved the activation of AR–SCAP–SREBPs-CYP17/HMGCR axis in neuroblastoma. The combination of inhibitors of HMGCR (statins) and CYP17A1 (abiraterone acetate) showed synergistic effect that significantly inhibited the proliferation and migration with decreased expression of related genes detected in vitro and in vivo suggesting the dual-targeted therapy had the potential to inhibit the progression of neuroblastoma in spite of its MYCN status. This study provides new ideas for clinical treatment of neuroblastoma with efficacy and reduced toxicity.

Abstract Background The cervical sagittal parameters of the normal population and the impact of disc degeneration on cervical sagittal alignment have not been clearly defined yet. This study is applied to investigate the characteristics and relationships of cervical sagittal parameters in normal adults and patients with cervical disc degeneration. Methods We reviewed 50 normal control subjects (normal group, NG) and 50 patients with cervical disc degeneration (degeneration group, DG), who had both cervical MRI and radiographs obtained together, between January 2010 and September 2015. Data including C2–7 lordosis (CL), T1 slope (T1S), thoracic inlet angle (TIA), neck tilt (NT), C2–7 sagittal vertical axis (C2–7 SVA), cervical tilting, and cranial tilting on cervical radiographs were collected and analyzed. Results T1S in the NG was significantly greater than in the DG (P

Stainless steel will become the substrate material of the flexible display, requirements of the flexible substrate in the surface quality and performance are very strict. Chemical mechanical polishing (CMP) is one of the most appropriate technologies to achieve the surface processing of ultra-thin stainless-steel flexible display substrate with ultra-smooth and damage-free. In this paper, the design of CMP slurry of 304 stainless steel on the hydrogen peroxide-oxalic acid type was proposed. Through experiment and analysis, the basic ingredients of CMP slurry was obtained. The research results showed that the hydrogen peroxide can increase the hydrophilicity of the stainless steel surface, and the Fenton type Haber-Weiss reaction can occur on the surface of the fresh metal substrate of stainless steel. The trivalent iron ions generated by the Fenton type reaction combined with oxygen to generate iron oxide and promoted the removal of the surface material. Under acidic conditions, the oxalic acid can decrease the stability of the oxide film on the stainless steel surface, promote the diffusion of oxygen into the metal interface, improve the oxygen reduction reaction, and increase the material removal rate. The results will provide an important reference for the next researching the CMP slurry of 304 stainless steel.

Phytochemical-mediated alterations in P-glycoprotein (P-gp) activity may result in herb-drug interactions by altering drug pharmacokinetics. Shengmai-san, a traditional Chinese herbal medicine composed by Panax Ginseng, Ophiopogon Japonicus, and Schisandra Chinensis, is routinely being used for treating various coronary heart diseases. In our previous studies, Schisandra Lignans Extract (SLE) was proved as a strong P-gp inhibitor, and herein, the compatibility of Shengmai-san was studied by investigating the influence of SLE on the pharmacokinetics of the ginsenosides from the perspective of P-gp.Pharmacokinetic experiments were firstly performed based on in vitro uptake, efflux and transport experiments in Caco-2, LLC-PK1 wild-type and MDR1-overexpressing L-MDR1 cells. During the whole experiment, digoxin, a classical P-gp substrate, was used as a positive control drug to verify the cells used are the valid models. Meanwhile, the effects of SLE on the pharmacokinetics of ginsenosides were further investigated in rats after single-dose and multi-dose of SLE.The efflux ratios of ginsenoside Rb2, Rc, Rg2, Rg3, Rd and Rb1 were found more than 3.5 in L-MDR1 cells and can be decreased significantly by verapamil (a classical P-gp inhibitor). Contrarily, the efflux ratios of other ginsenosides (Rh1, F1, Re, and Rg1) were lower than 2.0 and not affected by verapamil. Then, the effects of SLE on the uptake and transport of ginsenosides were investigated, and SLE was found can significantly enhance the uptake and inhibit the efflux ratio of ginsenoside Rb2, Rc, Rg2, Rg3, Rd and Rb1 in Caco-2 and L-MDR1 cells. Besides, In vivo experiments showed that single-dose and multi-dose of SLE at 500 mg/kg could increase the area under the plasma concentration time curve of Rb2, Rc and Rd significantly without affecting terminal elimination half-time. In conclusion, SLE could enhance the exposure of ginsenosides Rb2, Rc, Rg2, Rg3, Rd and Rb1 significantly.