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Objective: This study aimed to explore the quality features of basal tea of noval-jasmine tea. Methods: Taking three kinds of basal tea（Fujian Xianghao, Yunnan Maojian, Sichuan Xiangming）of noval-jasmine tea beverage scenting tea dhool from Fujian, Yunnan and Sichuan as the research objects, the quality of the base tea including main biochemical components, taste, aroma were analyzed by electronic tongue, solid phase microextraction combined with gas chromatography-mass spectrometry (GC-MS), sensory evaluation and chemical analysis. Results: Water extracts of three kinds of basal tea was 49.40%~51.40%, tea polyphenols was 18.00%~23.20%, caffeine was 3.20%~4.30%, free amino acid was 3.32%~3.50%. The main biochemical components and 16 kinds of amino acids of Yunnan Maojian were higher than the other two. The response values of acerbity, salty, richness of Yannan Maojian were the maximum, but the response value of sweet was the minimum, and tea soup was heavy and strong. The response values of acerbity and salty of Fujian Xianghao were the minimum, but the water extracts were high, and tea soup was thick and mellow. The contents of esters were the maximum, followed by alcohols and olefins. The order of aroma quality from high to low was Fujian Xianghao, Yunnan Maojian and Sichuan Xiangming，which were all middle degree by aroma evaluation. Conclusion: The inclusion of the three kinds of basal tea of noval-jasmine tea beverage were abundant, but the aroma quality needed improvement.

The corona virus disease 2019 (COVID-19) pandemic has created a global health and economic crisis. Our studies uncovered that in addition to respiratory symptoms, liver damage is also common in COVID-19 patients; however, the cause of liver damage has not been fully elucidated. In this article, we summarize the clinical manifestations and pathological features of COVID-19 reported in published relevant studies and delineate the etiology and pathogenesis of COVID-19-related liver injury. We speculate that cold stimulation may be associated with COVID-19-related liver injury, which should be considered in clinical decision-making and treatment of COVID-19 in cold regions.

A novel proton nuclear magnetic resonance (1H NMR) method for determining the absolute content of ticagrelor was proposed. The ideal spectra were obtained on a Bruker Avance-300 spectrometer with deuterated methanol (CD3OD) as the solvent and sulfadoxin as the internal standard. The ticagrelor signals at δH 7.14 (2H, m) and δH 7.04 (1H, s), as well as those of sulfadoxin at δH 8.04 (1H, s), δH 7.73 (2H, d) and δH 6.54 (2H, d), were selected for quantitative analysis. The detection conditions were as following:probe temperature 308 K, spectrum width 3 511.5 Hz, center frequency 1 470.6 Hz, pulse angle θ=30°, delay time (d1) 10 s, number of scans 16 and line broadening 0.3 Hz. The signals from ticagrelor and internal standard sulfadoxin showed good separation, precision, reproducibility, and wide linearity ranges with Y=1.053X-0.081 (r=0.996, n=5). The content of ticagrelor was estimated to be 99.4% (RSD=0.20%). This method was proven simple, accurate and rapid.

Polymeric vesicles with tertiary amine and epoxy functional groups were fabricated via the reversible addition-fragmentation chain transfer (RAFT) dispersion polymerization of 2-(diisopropylamino) ethyl methacrylate (DIPEMA) and glycidyl methacrylate (GlyMA) in an ethanol-water mixture by using poly (ethylene oxide)-4-(4-Cyanopentanoic acid) dithiobenzoate (mPEG45-CPADB) as the macro-chain-transfer agent (macro-CTA). Biocompatible polymer mPEG45 with molecular weight of 2000 and 4-(4-Cyanopentanoic acid) dithiobenzoate (CPADB) were used for the macro-CTA synthesizing via the esterification reaction. Investigation of the degree of polymerization (DP) of the hydrophobic block P(DIPEMA-co-GlyMA) and the solid content indicated that both have significant effect on the particle morphology and particle diameter. 1H NMR and FTIR analysis indicated the existing of tertiary amine and epoxy functional groups on the produced vesicles.

PP/FG composite materials were prepared by compressing moulding under high temperature through high-speed mixer, mixing mill and vulcanization machine taking PP as the matrix resin, FG as the thermal conductive filler, and NDZ-201 as the coupling agent. Effects of PP proportion, FG content and particle size on the thermal conductivity and mechanical properties of composite materials were studied. Results showed that PP proportion has little effect on the thermal conductivity of PP/FG composite materials, but it greatly affects the mechanical properties of the composite materials. Overall, the quality ratio of PP230 to K-4038 at 50:50 is more suitable. With the increasing of FG content, the thermal conductivity increases, and a significant critical value appears when the FG content is 50 wt%; The strength of the composite material first decreases and then increases, with an increase in modulus and a decrease in strain. As the FG particle size increases, the thermal conductivity of the composite material increases and the mechanical properties decrease.

A polyethylenimine adjuvant modified by mannose, which may be used in the study of vaccine adjuvant, was prepared in this paper. Its structure was characterized by infrared spectroscopy and its micromorphology was observed by transmission electron microscopy. A series of mannose-modified polyvinylimine were prepared according to the molar ratio of primary amine groups between mannose and polyvinylimine, and their storage stability was observed at 4°C. In addition, the cytotoxicity of modified and unmodified polyethylenimine was also tested, and the results showed that the modified polyethylenimine was less toxic than unmodified polyethylenimine.

Poly (lactic-co-glycolic acid) (PLGA) is a kind of medical polymer material with good biodegradability and histocompatibility, which is widely used in postoperative anti-adhesion materials. In this paper, PLGA microfiber membrane was successfully prepared with poly(lactic-co-glycolic acid) as the main material by electrospinning technology. The surface morphology, wettability, dimensional stability and mechanical properties of PLGA microfiber films were characterized by scanning electron microscopy (SEM) and tensile testing machine. The results show that the average diameter of the prepared PLGA fiber is 2.218~2.313 μm, the elongation at break of the fiber film is up to 193%, and the dimensional stability and wettability of the fiber film are maintained at 37°C. The degradation cycle is 2~3 months.

Polypropylene (PP) composite materials were prepared through two molding methods of injection and compression molding, taking PP, FG as the matrix and thermal conductive filler. The effects of molding methods and FG content on the thermal conductivity of composite materials were studied, and the SEM, XRD, and thermal expansion properties of the materials were further analyzed. Results showed that thermal conductivity of the composite material increases with increasing of the FG content. When the FG content was 75 wt%, the average thermal conductivity of the composite materials prepared by injection molding and compression molding is 9.88 W·m-1·K-1 and 6.03 W·m-1·K-1, respectively. The axial thermal conductivity is 16.6 W·m-1·K-1 and 1.35 W·m-1·K-1, and the radial thermal conductivity is 5.88 W·m-1·K-1 and 26.9 W·m-1·K-1, respectively. In composite materials formed by injection molding, the flaky FG is mainly oriented vertically, while in compression molding, the flaky FG is mainly oriented horizontally.

2-(diisopropylamino) ethyl methacrylate (DIPEMA) and glycidyl methacrylate (GlyMA) were used for the investigation of the redox-initiated reversible addition-fragmentation chain transfer (RAFT) dispersion polymerization, by using poly (ethylene oxide)-4-(4-Cyanopentanoic acid) dithiobenzoate (mPEG-CPADB) as the macro-chain-transfer agent (macro-CTA). The particle growth process study indicated that the particles changed from spheres to worms, and then to vesicles during the polymerization process. The degree of polymerization (DP) of the hydrophobic block P(DIPEMA-co-GlyMA) affected the particle morphology, particle diameter and molecular weight significantly. Pure polymeric vesicles could be obtained when DP was equal to or higher than 60, and with increasing of the DP of the hydrophobic block, the diameter and the molecular weight of the particles both increased.

The built-in test of the aircraft can identify the fault on the automatic flight control computer when the automatic flight control computer is in failure. The ground crew deliver the automatic flight control computer to supplier for testing and maintenance, which is wasting time and ineffective, so the general automatic testing platform is designed. The interface and function modules, which need to be simulated are identified by the general automatic testing platform through researching the interface relationship of the automatic flight control computer. The hardware platform of the general automatic testing technology based on general standard instrument bus architecture, and the software platform based on standard automatic test makeup language(ATML) description to realize the hardware free extension, software independence, and portability independent of hardware and operating system. According to the interface, function and composition architecture design of automatic flight control computer, the test methods and test flow of each functional module are designed, and compiled into the operational test assemble with ATML. The platform is of good effect on trial, can can realize fast locating of fault module, and shorten the maintenance time.

The surface modified flake graphite (FG) was filled into polypropylene (PP) and mixed by a double-roll open mill. FG/PP composites with high thermal conductivity were prepared by compression molding. Studies had shown that the modification of FG by coupling agent was beneficial to the dispersion in FG/PP composites. The effect was better when the amount of NDZ-201 was 0.7wt%. With the increase of FG particle size, the thermal conductivity of FG/PP composites increased obviously. Compared with 17μm FG, the average, vertical and parallel thermal conductivity of FG/PP composites prepared with 148μm FG increased by 65.9%, 87.7% and 47.0% respectively. The thermal conductivity of FG/PP composites were improved with the increase of FG content. When FG content was 70wt%, the thermal conductivity increased significantly, the average, vertical and parallel thermal conductivity reached 4.16 W·m-1·K-1, 0.938 W·m-1·K-1 and 18.4 W·m-1·K-1.

This study describes a polymer potentially used as a vaccine adjuvant. We first synthesized a novel polyacrylic acid modified by perfluorinated butanol—a bioactive compound that is biocompatible. The main aim was to functionalize the polyacrylic acid by fluorine. This functionalization could offer a permanent graft by an esterification reaction. The chemical structure of the polymer has been characterized by the hydrogen nuclear magnetic resonance spectrum (1H-NMR) and fourier transform infrared spectrum (FT-IR). Thermal analysis showed that the esterification reaction was successful on the polyacrylic acid. Viscosity testing showed that the viscosity of the sample aqueous solution increases along with esterification. The surface tension of the polymer was also tested. The results show that the surface tension of the polyacrylic acid markedly decreased when modified by fluorine. Finally, the interaction of these materials with macrophages was tested on cell test. Results showed that the modified polyacrylic acid performed better improve the activation effect than pure polyacrylic acid in 1L-1β.

Microteaching practice is an important part of Pre-Service Physics Teacher (PsPT) Training Program adopting different approaches to inspire the acquisition of teaching skills by prospective teachers. Using psychomotor domain aspect of revised Bloom's taxonomy to explore microteaching practice as it relates to physics teaching, this research examined the significant influences of the two approaches (Nigeria and China) identified on the teaching skill of PsPT and suggests the best ways of improving the teaching skill of PsPT through micro-teaching practices. Data were collected using the mixed-method research design of administering descriptive survey questionnaire on final year PsPT while a structured interview question was used to interview the teachers. It was found that the two approaches had significant influences on the teaching skill acquisition of PsPT through microteaching practices with respect to physics as a subject that requires motor skill, and that this can be improved through micro-teaching by a combination of theory with practice. Also, physics teacher educators need to focus on developing PsPTs' psychomotor domain in line with time reform in microteaching practices to accommodate more time for PsPTs' to master the subject concept of physics as a psycho motive subject.