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This paper analyzes the present situation and problems of online opening excellent experiment course in our country, such as few of open videos of the experimental training class, single mode, lack of systematicness and diversity of course types, and difficulty in construction, etc. In this paper, the construction of high-quality video open course of "biochemistry experiment" was treated as an example in order to elaborate the strategies of building the experiment course. It is necessary to arouse teachers' enthusiasm. The teaching content, teaching method and video style were meticulously optimized and designed to construct excellent experiment course by starting with the accurate positioning of the construction goal, the establishment of the construction team and the writing of the shooting script, outline, and lecture. The video contents of the experimental course should be elaborated by carefully shooting video materials, attaching importance to the post-production of video, and strictly checking the quality. This should provide a reference for the development and research of experimental teaching video at the background of digitalization. [ABSTRACT FROM AUTHOR]

Abstract: Manganese oxide (MnO2) is a promising pseudocapacitive electrode material because of its high capacitance, abundant resource, low-cost, and environmental friendliness. However, its poor electrical and ionic conductivities and low stability hinder applications. Forming MnO2 nanocomposites with high surface area porous metal, carbon materials, or conducting polymers is a possible solution. In this work, we have developed a facile and scalable asymmetric in situ deposition method to incorporate MnO2 nanoparticles in conductive single walled carbon nanotube (SWCNT) films. The high porosity of vacuum filtrated SWCNT films accommodates pseudocapacitive MnO2 nanoparticles without sacrificing the mechanical flexibility and electrochemical stability of SWCNT films. We exposed one side of SWCNT films to acidic potassium permanganate (KMnO4) solution. The infiltrated KMnO4 solution partially etches SWCNTs to create abundant mesopores, which ensure electrolyte ions efficiently access deposited MnO2. Meanwhile, the remaining SWCNT network serves as excellent current collectors. The electrochemical performance of the SWCNT–MnO2 composite electrodes depends on the porosity of SWCNT films, pH, and concentration of KMnO4 solution, deposition temperature and time. Our optimized two-electrode electrochemical capacitor, with 1M Na2SO4 in water as electrolyte, showed a superior performance with specific capacitance of 529.8Fg−1, energy density of 73.6Whkg−1, power density of 14.6kWkg−1, excellent capacitance retention (99.9%) after 2000 charge and discharge cycles, and one of the highest reported frequency responses (knee frequency at 1318Hz). The high performance flexible electrochemical capacitors have broad applications in portable electronics and electrical vehicles, especially when high frequency response is desired. [Copyright &y& Elsevier]

Objective: To analyze the imaging features of Struma ovarii (SO), and to correlate the imaging results with the pathological findings so as to enhance the knowledge of the imaging diagnostics of this disease. Methods: The clinical records, CT and MRI features of twelve patients with pathologically proved SO were retrospectively analyzed. Imaging features were compared with pathological results. Results: Most tumors ( n = 11, 91.7%) were unilateral. In CT and MRI images, the lesions presented as defined irregularly shaped masses, showing mainly cystic ( n = 6, 50%) or cystic ( n = 6, 50%). The cystic portions presented as well defined, multiple, various size, and a whole cyst wall with smooth inner wall. Eight cases of tumors (66.7%) showed a high attenuation lesion in the cyst portion of the mass on CT precontrast scans, in which two cases showed high signal on T1WI and low signal on T2WI. The solid portions, which distributed in the cyst showed irregular tissue density. After contrast administration, the cystic portions showed no enhancement, the solid portions marked enhancement, and the cyst wall demonstrated no, moderate, or marked enhancement. Eight cases of tumors (66.7%) showed stippled calcification in the cyst wall. Four cases of tumors (33.3%) accompany a great of abdominal dropsy and pleural fluid. Conclusions: In general, SO appeared as a smooth marginated multicystic mass with a high attenuation lesion on precontrast scans on CT scans, and signal intensities on T1-weighted images were partly intermediate to high, or high, and those on T2-weighted images were low. The CT and MRI characteristic findings of SO might be of great value for the diagnosis. [ABSTRACT FROM AUTHOR]

Abstract: Coral-like accretion of hollow carbon microspheres with thin walls has been successfully synthesized through a carbon dissolution–precipitation process, where the decomposition of cyclohexane on nickel powder, at 550°C in a sealed system, and is followed by rapid cooling. The final product is tens of microns in size with smooth and uniformly thin shell thickness of approximately 3–4nm. XRD, FESEM, EDX, TEM, HRTEM and Raman spectra were used to characterize the products. The effects of reaction temperature, type of carbon source and cooling process on the formation of the final products have been studied, and a possible formation mechanism for the coral-like product has been proposed. This coral-like accretion of large capacity hollow carbon microspheres has potential applications as a catalyst carrier, in storage or protection of unstable organic materials and microreactors. [Copyright &y& Elsevier]

Cubic fluoroperovskite KMnF3 nanostructures including acicular nanocrystals and ultrafine nanoparticles were solvothermally synthesized. [Copyright &y& Elsevier]

The purpose of the study was to evaluate the value of high-resolution three-dimensional fast low angle shot (3D-FLASH) and three-dimensional constructive interference in steady-state (3D-CISS) MRI sequence solely or the combination of both in the visualization of neurovascular relationship in patients with trigeminal neuralgia (TN). 65 patients with unilateral TN underwent 3D-FLASH and 3D-CISS imaging were retrospectively studied. Neurovascular relationship at the intracisternal segment of trigeminal nerve was reviewed by two experienced neuroradiologist, who was blinded to the clinical details. The imaging results were compared with the operative findings in all patients. The accuracy and positive rates of the 3D-FLASH + CISS imaging (98.46, 92.31%) in judging the symptomatic side according to the presence of vascular contacts were higher than those of 3D-CISS (90.77%, 84.62) or 3D-FLASH (89.23, 83.08%) sequence. In addition, the statistical analysis showed the sensitivity and accuracy of 3D-FLASH + CISS imaging was higher than that of 3D-FLASH (p < 0.05). The 3D-FLASH + CISS imaging was more accurate in determining the type of offending vessel than 3D-CISS or 3D-FLASH imaging. The retrospective study demonstrates that the combination of 3D-FLASH with 3D-CISS sequence well delineates the relationship between intracisternal segment of trigeminal nerve and adjacent vessels in terms of increased positive rates and accuracy. The study firstly dealt with the combination of 3D-CISS and 3D-FLASH imaging in TN. [ABSTRACT FROM AUTHOR]

An enzyme-free, metal-free, and preconcentration-free electrochemical sensor for pentachlorophenol assay has been fabricated. The interface of the sensor is based on a hollow zeolitic imidazolate framework–derived mesoporous carbon material (denoted as HZC/SPCE). The sensor exhibits linear amperometric response upon pentachlorophenol at 0.82 V (vs. Ag/AgCl) in the concentration range 0.001 to 26.8 mg L−1 (3.75 × 10−8~1.006 × 10−4 M) (R2 = 0.997). The sensitivity of HZC/SPCE is 3.53 × 102 μA mM−1 cm−2 with a detection limit of 2.05 × 10−9 M (S/N = 3) for pentachlorophenol. The method has been applied to the determination of pentachlorophenol in spiked food packaging samples with recoveries in the range 92.0 to 107.0%. [ABSTRACT FROM AUTHOR]

Gas chromatography – tandem mass spectrometry (GC-MS/MS) using formic acid as a protective agent is reported for the determination of acrylic resin monomers in food contact packaging paper. The analytes were extracted by ethanol mixed with formic acid with 2-phenylethyl propionate as the internal standard. The extract was separated by a 6% cyanopropylbenzene-94% dimethylsiloxane ultra-inert chromatographic column and analyzed by GC-MS/MS in multiple reaction monitoring (MRM) mode. 13 acrylic resin monomers including acrylic acid, styrene, and acrylic ester were separated. The procedure was successfully applied for the analysis of real samples. The procedure provided a linear calibration range with detection limits from 0.16 to 0.46 mg kg−1. The mean recoveries were from 88.1% to 100.9% with relative standard deviations less than 5.4%. The residual acrylic resin monomers in packaging paper were primarily from printing base paper and varnish. Of the acrylic resin monomers, the monomers except for butyl acrylate and 2-ethylhexyl acrylate showed low migration rates. The method provides high sensitivity and good reproducibility with simple pretreatment, demonstrating application for monitoring acrylic resin monomers in food contact packaging paper. [ABSTRACT FROM AUTHOR]

• The effect of floating I and ⊥-baffles with different mass on the suppression of Faraday waves is tested experimentally. • Changes in mass and additional mass of floating baffles lead to significantly different sloshing suppression effects • A lighter floating I-baffle perform better than a fixed one, and the suppression effect can be improved by changing their additional mass for a heavier one. Liquid sloshing in a storage tank is a common phenomenon that can significantly damage the tank structure by leading to high local pressure on the sidewalls. Faraday waves, a special phenomenon caused by vertical excitation, contribute significantly to sloshing. Therefore, a physical model test was conducted in this study to suppress Faraday waves by employing I- and ⊥-baffles. The experimental results indicated that the movement of the floating baffles enhanced their virtual height. Furthermore, the mass and added mass of the floating baffles were analysed. The suppression effect of the lighter floating I-baffle was better than that of the fixed baffle. The ⊥-baffle was proposed by adding a horizontal part at the bottom of the floating I-baffle, and it could improve the suppression effect when the floating baffles were heavy. [ABSTRACT FROM AUTHOR]

Highly photoluminescent ZnSe/Au nanocomposites have been prepared via a simple low-temperature-aqueous synthesis and direct coupling approach. The mechanism of surface plasmons enhanced photoluminescence of ZnSe/Au nanocomposites is investigated. Furthermore, due to high photostability and biocompatibility, the as-prepared ZnSe/Au nanocomposites are demonstrated as excellent probes in cellular imaging. [ABSTRACT FROM AUTHOR]

Abstract: Focused metabolic profiling is a powerful tool for the determination of biomarkers. Here, a more global proton nuclear magnetic resonance (1H NMR)-based metabolomic approach coupled with a relative simple ultra high performance liquid chromatography (UHPLC)-based focused metabolomic approach was developed and compared to characterize the systemic metabolic disturbances underlying esophageal cancer (EC) and identify possible early biomarkers for clinical prognosis. Serum metabolic profiling of patients with EC (n=25) and healthy controls (n=25) was performed by using both 1H NMR and UHPLC, and metabolite identification was achieved by multivariate statistical analysis. Using orthogonal projection to least squares discriminant analysis (OPLS-DA), we could distinguish EC patients from healthy controls. The predictive power of the model derived from the UHPLC-based focused metabolomics performed better in both sensitivity and specificity than the results from the NMR-based metabolomics, suggesting that the focused metabolomic technique may be of advantage in the future for the determination of biomarkers. Moreover, focused metabolic profiling is highly simple, accurate and specific, and should prove equally valuable in metabolomic research applications. A total of nineteen significantly altered metabolites were identified as the potential disease associated biomarkers. Significant changes in lipid metabolism, amino acid metabolism, glycolysis, ketogenesis, tricarboxylic acid (TCA) cycle and energy metabolism were observed in EC patients compared with the healthy controls. These results demonstrated that metabolic profiling of serum could be useful as a screening tool for early EC diagnosis and prognosis, and might enhance our understanding of the mechanisms involved in the tumor progression. [Copyright &y& Elsevier]

Machine learning techniques exhibit significant performance in discriminating different phases of matter and provide a new avenue for studying phase transitions. We investigate the phase transitions of three dimensional q -state Potts model on cubic lattice by using a transfer learning approach, Domain Adversarial Neural Network (DANN). With the unique neural network architecture, it could evaluate the high-temperature (disordered) and low-temperature (ordered) phases, and identify the first and second order phase transitions. Meanwhile, by training the DANN with a few labeled configurations, the critical points for q = 2 , 3 , 4 and 5 can be predicted with high accuracy, which are consistent with those of the Monte Carlo simulations. These findings would promote us to learn and explore the properties of phase transitions in high-dimensional systems. • DANN can locate the transition point with a few input configurations labeled. • DANN can classify the high-temperature and low-temperature phases. • The critical exponent ν is obtained the continuous phase transition. • The type of phase transition could be determined through the output of DANN. [ABSTRACT FROM AUTHOR]

Purpose: To screen for the potential protein biomarkers in serum for the diagnosis of esophageal carcinoma (EC) using proteomic fingerprint technology. Methods: Proteomic fingerprint technology combining magnetic beads with MALDI-TOF-MS was used to profile and compare the serum proteins from 78 patients with EC and 95 healthy blood donors. Proteomic patterns associated with EC were identified by Biomarker Patterns Software. Model of biomarkers was constructed and evaluated using the Biomarker Patterns Software. Results: A total of 60 discriminating m/ z peaks were identified that were related to EC ( P < 0.01). The model of biomarkers constructed by the Biomarker Patterns Software based on the four biomarkers (2049.6, 3936.5, 5339.9, and 13748.8 Da) generated excellent separation between the EC and control groups. The sensitivity was 92.5% and the specificity was 88%. Blind test data indicated a sensitivity of 89.5% and a specificity of 84.4%. Conclusions: Biomarkers for EC can be discovered in serum by MALDI-TOF-MS combining the use of magnetic beads. The pattern of combined markers provides a powerful and reliable diagnostic method for EC with a high sensitivity and specificity. [ABSTRACT FROM AUTHOR]

Double fold hexagonal dendrites (DFHD) of copper(I) sulfide with D6h point group symmetry were synthesized by an ammonia-assisted hydrothermal process. The growth direction of the branches in DFHD could be tuned by adjusting the concentration of reagents, such as Cu2+ and NH3. Studies show that the coordination effect between copper anion and ammonia ligands plays a crucial role in the formation of the final dendritic structure. The influences of the reaction temperature and time on the morphology of the product have been also discussed. A possible formation process of this novel DFHD has been proposed on the basis of experiments. Double fold hexagonal dendrites of Cu2S with high geometrical symmetry structure could be obtained via inorganic ions participated coordination chemistry method. The growth habit of the Cu2S dendrites could be modulated via this facile nonorganic reagent participating hydrothermal route. [ABSTRACT FROM AUTHOR]

Conventional epoxy asphalt is a thermosetting material that is difficult to reprocess and cannot be easily recycled after disposal. In this study, a lignin-based epoxy asphalt (ELEA) with thermoplastic and thermosetting properties was prepared by introducing a lignin-based vitrimer system, which has a dynamic, covalently bonded, cross-linked ester network, into the asphalt. The mechanical properties (tensile strength, 1.605 MPa; elongation at break, 382.38 %) also meet the requirements of epoxy asphalt for steel bridge deck pavement. The viscosity, thermal properties and high-temperature reversibility of ELEA show that ELEA has good operability, thermal stability and potential for recycling, in line with the trend towards the development of a circular economy. The use of biomass-based derivatives for the epoxy resin and curing agent in ELEA also reduces dependence on non-renewable petroleum resources and provides a useful reference for the high-value and efficient development and utilization of industrial lignin. [Display omitted] • Using lignin as raw material can effectively utilize low-value biomass resources. • Vitrimer containing dynamic covalent bonds is introduced to make asphalt thermosetting thermoplastic. • It has better rheological properties and recovery potential. [ABSTRACT FROM AUTHOR]

A transfer learning method, Domain Adversarial Neural Network (DANN), is introduced to study the phase transition of two-dimensional q -state Potts model. With the DANN, we only need to choose a few labeled configurations automatically as input data, then the critical points can be obtained after training the algorithm. By an additional iterative process, the critical points can be captured to comparable accuracy to Monte Carlo simulations as we demonstrate it for q = 3 , 4 , 5 , 7 and 10. The type of phase transition (first or second-order) is also determined at the same time. Meanwhile, for the second-order phase transition at q = 3 , we can calculate the critical exponent ν by data collapse. Furthermore, compared to the traditional supervised learning, we found the DANN to be more accurate with lower cost. • DANN can predict the critical point with a few input configurations labeled. • The critical exponent ν is obtained by data collapse at q = 3. • The type of phase transition is determined through the output of DANN. • The algorithm is of high accuracy and low cost in studying the phase transition. [ABSTRACT FROM AUTHOR]

Abstract: Highly Photoluminescent (PL) carbon dots (CDs) with a PL quantum yield (PLQY) of 7.7% have been prepared from cornflour by a simple hydrothermal method. The as-prepared carbon dots have good water solubility, well distributed particle size, amorphous structure and acceptable fluorescence lifetime. Besides, due to the fairly good biocompatibility and outstanding fluorescent properties, the CDs were successfully applied to cell imaging and Cu2+ detecting. [Copyright &y& Elsevier]

Water-soluble, fluorescent carbon dots (CDs) have been successfully synthesized from waste paper. The as-prepared CDs, with an amorphous structure and small particle size, exhibit good photostability, high photoluminescence quantum yields (PLQYs) and fairly low toxicity, which indicate potential applications in the field of biolabelling. [ABSTRACT FROM AUTHOR]

In the present study, ZnS and ZnO quantum dots (QDs) were synthesized via an all-aqueous process with polyethylene glycol (PEG) chains on their surface, and their toxicity as well as biodistribution were evaluated. No haemolysis occurred at a high concentration of 1600 µg/mL in vitro haemolytic assay, which demonstrated that the QDs-PEG displayed good blood compatibility. Following intravenous administration at 2, 6, and 20 mg/kg of the QDs-PEG in mice, the biodistribution, excretion and biocompatibility were characterized at 1 h, 24 h and 7 days, respectively. Quantitative analysis results indicated that the biodistribution trend of ZnS QDs-PEG was similar to that of ZnO QDs-PEG. The QDs-PEG were mainly trapped in the lung and liver, and almost removed from blood within 1 h. QDs-PEG were primarily excreted in faeces at the 2 and 6 mg/kg doses. Coefficients, haematology, blood biochemistry and histopathology results indicated that the QDs-PEG were safe and biocompatible. [ABSTRACT FROM AUTHOR]

Abstract: A native polysaccharides (GPP2) was isolated from Gynostemma pentaphyllum Makino. Four sulfated derivatives of GPP2 (GPP2-s1 to s4) were prepared by chlorosulfonic acid method with ionic liquids (ILs) as solvent and 4-dimethylaminopyridine (DMAP) as catalyst. The structures of the sulfated derivatives were analyzed by FT-IR spectra and 13C NMR spectra, which indicated that the sulfated groups were introduced mainly at the C-6 position as well as at the C-2 position. The products showed different degree of substitution (DS) ranging from 0.79 to 1.34, and different weight-average molecular mass (Mw) ranging from 8.64 to 11.2Da. The sulfated derivatives inhibited the growth of HepG2 cells and Hela cells in vitro significantly. Furthermore, they had no obvious influence on 293 cells, which indicated that they had low toxicity. Flow cytometric studies revealed that treatment of the sulfated derivatives with Hela cells could mediate the cell-cycle arrest in the S phase. [ABSTRACT FROM AUTHOR]