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Oil red O was applied as precursor to synthesize nitrogen-doped carbon dots (NCDs) by a facile solvothermal method for the first time. Surprisingly, liquid–liquid extraction and purification resulted in the quantum yield (QY) of NCDs up to 68%. The purification mechanism is based on the difference in polarity and solubility between precursor, over-carbonized substances and NCDs. Further, optical properties and structure characterizations of NCDs were characterized by ultraviolet (UV) spectroscopy, fluorescence (FL) spectroscopy, transmission electron microscopy (TEM), Fourier-transform infrared (FT-IR) spectroscopy, X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). Importantly, NCDs can be acted as an outstanding multi-functional sensing platform for Cu2+ and tetracycline antibiotics (TCs). Compared with other coexisting metal ions and antibiotics, this platform showed special responses to Cu2+ and TCs. NCDs showed high selectivity and sensitivity of fluorescence response to Cu2+ over a broad range of 10 nM −50 μM and a satisfactory detection limit (LOD)of 4 nM. Besides, NCDs also showed high sensitivity for the detection of TCs with a LOD range of 50 pM-100 nM. In addition, the fluorescent quenching mechanism of Cu2+ and TCs to NCDs were identified as IFE and static quenching. Finally, the platform was successful applied to detect Cu2+ and TCs in actual samples (e.g., water, milk, urine) with satisfactory results. All results indicated that NCDs appeared to have tremendous potential for Cu2+ and TCs detection in various fields.

Tian-quan Yang,1,* Min Chen,1,* Yong-qiang Wang,1 Wei Xu,1 Yong Han,1 Jin Xu,1 Yong-jun Xiang,1 Bin Yuan,1 Hang-zhou Wang,1 You-xin Zhou2 1Department of Neurosurgery, Children’s Hospital of Soochow University, 2Department of Neurosurgery and Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, Suzhou, People’s Republicof China *These authors contributed equally tothis work Abstract: Glioma is one of the most common types of adult primary brain tumors, and the underlying molecular mechanisms still remain unclear. Nuclear factor-kappa B1 (NF-κB1) is involved in a variety of malignancies and is widely expressed in malignant tumors. However, the expression of NF-κB1 in different grades of glioma, the correlation between NF-κB1 and Bcl-2 expressions in gliomas, and the research between NF-κB1 and early apoptosis of glioma cells have not been reported so far. In this study, the expression level of NF-κB1 in 31human glioma tissues and six nonneoplastic brain tissues was determined using quantitative real-time polymerase chain reaction. Results showed that the expression of NF-κB1 in human glioma ­tissues and glioma cell lines, SHG44 and U87, was significantly higher compared to noncancerous brain tissues and that the expression increased with increasing degrees of tumor malignancy. Similar results were demonstrated with the expression of Bcl-2 in the same human glioma specimens. Flow cytometry results showed that inhibition of NF-κB1 expression significantly promoted apoptosis of SHG44 and U87 in human glioma cells. Western blot analysis further confirmed decreased expression of Bcl-2 protein after inhibition of NF-κB1 protein expression. Taken together, NF-κB1 overexpression inhibits early apoptosis of glioma cells and high expression of NF-κB1 promotes the expression of antiapoptotic gene Bcl-2. Therefore, our study results provide a theoretical basis for antiapoptotic mechanism of tumor cells in association with NF-κB1. Keywords: NF-κB1, Bcl-2, glioma, apoptosis

Background The gut microbiome exerts extensive roles in metabolism of nutrients, pharmaceuticals, organic chemicals. Little has been known for the role of gut microbiota in regulating cholesterol and bile acids in association with gallstone formation. This study investigated the changes in the composition of gut microbiota in mice fed with lithogenic diet (LD). Methods Adult male C57BL/6 J mice were fed with either lithogenic diet (1.25% cholesterol and 0.5% cholic acid) or chow diet as control for 56 days. The fecal microbiota were determined by 16S rRNA gene sequencing. Results LD led to formation of cholesterol gallstone in mice. The richness and alpha diversity of gut microbial reduced in mice fed with LD. Firmicutes was significantly decreased from 59.71% under chow diet to 31.45% under LD, P

In this study, an eco-friendly extraction method that used tailor-made deep eutectic solvents (DESs) for the extraction of oxymatrine and matrine from Sophora flavescens Aiton root was implemented for the first time. The extraction parameters, including the DES type, DES water content, solid-to-liquid ratio, extraction time, and extraction temperature, which affected the extraction efficiencies of oxymatrine and matrine were optimised. High-performance liquid chromatography with a diode-array detector and quantitative analysis of the DES components was conducted. The highest oxymatrine and matrine extraction yields (21.04 and 1.53 mg·g−1, respectively) were obtained using DES-2 (comprising choline chloride and malonic acid; molar ratio of 1:2) with 50% water and DES-8 (comprising choline chloride and ethylene glycol; molar ratio of 1:2) with 30% water as the extraction solvents, respectively. Furthermore, magnetic molecularly imprinted polymers (MMIPs) were successfully synthesised using oxymatrine, acrylic acid, ethylene glycol dimethylacrylate, azobisisobutyronitrile, and acetonitrile–methylbenzene (3:1, v/v) as the template, functional monomer, cross-linker, initiator, and porogen, respectively. The MMIPs were characterised using transmission electron microscopy, Fourier-transform infrared spectroscopy, and X-ray diffraction analyses, and the results demonstrated the successful preparation of MMIPs. The adsorption properties of MMIPs were further analysed using static and dynamic adsorption experiments, and the results indicated that MMIPs presented good adsorption capacities for oxymatrine and matrine (110.8 and 63.4 mg·g−1, respectively). Lastly, MMIPs were used as sorbents for the extraction and enrichment of oxymatrine and matrine from DES extracts of S. flavescens roots. The extraction efficiencies of oxymatrine and matrine (80.21–89.15% and 85.33–95.28%, respectively) were satisfactory. The proposed DES-based extraction followed by MMIPs secondary enrichment appeared to be an effective method for the selective extraction of specific components from complex samples.

A new dynamic equation of aerosol in air is derived, using a model-in-model, by equilibrium of buoyancy, gravity and pressure, together with conservation laws of mass, momentum and energy via Reynolds transport theorem and supplemented by corresponding scientific laws for related properties of air and aerosols. This new dynamic equation of aerosol in air is a set of non-linear partial differential equations involved six unknown functions of mass densities, pressure, air and aerosol speeds and temperature. It has features: 1, it belongs to certain type; 2, it emphases the effect of buoyancy in equilibrium and potential energy, and the Archimedes principle of buoyancy is firstly extended to lateral directions based on logical deduction, the phenomenon of stirring a glass of oil-water mixture and the recorded of Hurricane Isabel (2003) from space station. The later shows the evidence of existence of lateral buoyancy; 3, the mass densities of air and aerosol of a point in our model are varied in different directions due to traction and are treated as vectors, and they have been used in the calculation of lateral buoyancy.

A new fluorescence composite material for the sensitive and selective determination of 4-nitrophenol (4-NP) was developed based on molecularly imprinted polymers (MIPs) incorporated with carbon dots (CDs). First, fluorescent CDs with a high quantum yield (QY) of 51.8% were prepared by hydrothermal synthesis method by using anhydrous citric acid as carbon source and AEAPMS as surface modifier. Then, CDs were fabricated with MIPs (CDs@MIPs) by sol–gel method using 4-NP as template, (3-aminopropyl) triethoxysilane (APTES) as functional monomer, tetraethoxysilane (TEOS) as cross-linker and CDs as signal sources, respectively. The CDs@MIPs exhibited strong fluorescence property and high selectivity to 4-NP as it incorporated merits of CDs and MIPs. Under optimized conditions, the relative fluorescence intensity of CDs@MIPs decreased linearly with the concentration of 4-NP from 0.025[Formula: see text][Formula: see text]g[Formula: see text]mL[Formula: see text] to 5[Formula: see text][Formula: see text]g[Formula: see text]mL[Formula: see text]. The limit of detection (LOD) of 4-NP was 5[Formula: see text]ng[Formula: see text]mL[Formula: see text] (35[Formula: see text]nM). Specificity and selectivity experiments showed that CDs@MIPs can selectively detect 4-NP with rare interference of other competitive analogs and metal ions. Finally, CDs@MIPs was successfully used to detect 4-NP in river water samples with the recoveries ranging from 94.0% to 103.4%. The results demonstrated that the prepared CDs@MIPs can be applied to the selective and sensitive detection of trace 4-NP in real samples.

The influence of temperature on mode coupling effect in piezoelectric vibrators remains unclear. In this work, we discuss the influence of temperature on two-dimensional (2D) mode coupling effect and electromechanical coupling coefficient of cylindrical [001] c -poled Mn-doped 0.24PIN–0.46PMN–0.30PT piezoelectric single-crystal vibrator with an arbitrary configuration ratio. The electromechanical coupling coefficient k t decreases with temperature increasing, whereas k 33 is largely invariant in a temperature range of 25 °C–55 °C. With the increase of temperature, the shift in the ‘mode dividing point’ increases the scale of the poling direction of the piezoelectric vibrator. The temperature has little effect on coupling constant Γ. At a given temperature, the coupling constant Γ of the cylindrical vibrator is slightly greater than that of the rectangular vibrator. When the temperature changes, the applicability index (M) values of the two piezoelectric vibrators are close to 1, indicating that the coupling theory can be applied to piezoelectric vibrators made of late-model piezoelectric single crystals.