Development of 2D- and 3D-BTEM for pattern recognition in higher-order spectroscopic and other data arrays

Ph.DDOCTOR OF PHILOSOPH

In Situ Electrochemical Derivation of Sodium-Tin Alloy as Sodium-Ion Energy Storage Devices Anode with Overall Electrochemical Characteristics

Inspired by the fermentation of multiple small bread embryos to form large bread embryos, in this study, the expansion of tin foil inlaid with sodium rings in the process of repeated sodium inlaid and removal was utilized to maximum extent to realize the formation of sodium-tin alloy anode and the improvement of sodium storage characteristics. The special design of Sn foil inlaid with Na ring realized the in-situ electrochemical formation of fluffy porous sodium-tin alloy, effectively alleviated the volume expansion and shrinkage of non-electrochemical active Sn metal, and inhibited the generation of sodium dendrites. The abundance of sodium ions provided by the Na metal ring compensated for the active sodium components consumed during the repeated formation of SEI. When sodium-tin alloy in situ derived by Sn foil inlaid with Na ring was used as negative electrodes matched with SCDC and Na0.91MnO2 hexagonal tablets (NMO HTs) positive electrodes, the as-assembled sodium-ion energy storage devices present high specific capacity and excellent cycle stability

Amino-methyl coumarin as a potential SERS@Ag probe for the evaluation of protease activity and inhibition

International audienceProteases are found deregulated in many diseases including cancer and neurodegenerative diseases. They thus represent good therapeutical targets for the development of inhibitors mainly small organic molecules. Peptide substrates containing fluorogenic groups constitute central tools for the monitoring of protease activities and inhibitor screening platforms. Amino-methyl coumarin (AMC) is a well-known fluorogenic group that functionalized a huge number of peptide substrates used for kinetics in vitro but also in vivo. However, either autofluorescence or quenching of the AMC fluorescence could compromise selection and accurate evaluation of these inhibitors. It is thus needed to explore alternative spectroscopic tools to unravel these limitations. Here, we investigate whether AMC could constitute a valuable Surface Enhanced Raman Spectroscopy probe in the presence of Creighton' silver colloids under 532-nm excitation to monitor protease activity and to evaluate inhibitors. The kallikrein-related peptidase 8 was used as model of proteolytic enzyme. Band-Target Entropy Minimization analysis was successfully used to validate the present Surface Enhanced Raman Spectroscopy approach

Typical Construction Technology and Method of UHV Main Transformer

According to the latest experience of UHV transformer on-site installation work, according to the rules and regulations requirements, the construction process and process of UHV transformer are summarized, and a typical UHV transformer construction method commonly used at present is obtained. Operation comes down to the arrival of acceptance, annex installation, vacuum oiling and hot oil circulation, sealing inspection, standing five processes. In accordance with the above process steps, this paper is divided into five parts to introduce the process and method of UHV transformer construction in order to guide the on-site construction and training teaching

Typical Construction Technology and Method of UHV Main Transformer

According to the latest experience of UHV transformer on-site installation work, according to the rules and regulations requirements, the construction process and process of UHV transformer are summarized, and a typical UHV transformer construction method commonly used at present is obtained. Operation comes down to the arrival of acceptance, annex installation, vacuum oiling and hot oil circulation, sealing inspection, standing five processes. In accordance with the above process steps, this paper is divided into five parts to introduce the process and method of UHV transformer construction in order to guide the on-site construction and training teaching

Immediate visual reproduction negatively correlates with brain entropy of parahippocampal gyrus and inferior occipital gyrus in bipolar II disorder adolescents

Abstract Background Brain entropy reveals complexity and irregularity of brain, and it has been proven to reflect brain complexity alteration in disease states. Previous studies found that bipolar disorder adolescents showed cognitive impairment. The relationship between complexity of brain neural activity and cognition of bipolar II disorder (BD-II) adolescents remains unclear. Methods Nineteen BD-II patients (14.63 ±1.57 years old) and seventeen age-gender matched healthy controls (HCs) (14.18 ± 1.51 years old) were enlisted. Entropy values of all voxels of the brain in resting-state functional MRI data were calculated and differences of them between BD-II and HC groups were evaluated. After that, correlation analyses were performed between entropy values of brain regions showing significant entropy differences and clinical indices in BD-II adolescents. Results Significant differences were found in scores of immediate visual reproduction subtest (VR-I, p = 0.003) and Stroop color-word test (SCWT-1, p = 0.015; SCWT-2, p = 0.004; SCWT-3, p = 0.003) between the two groups. Compared with HCs, BD-II adolescents showed significant increased brain entropy in right parahippocampal gyrus and right inferior occipital gyrus. Besides, significant negative correlations between brain entropy values of right parahippocampal gyrus, right inferior occipital gyrus and immediate visual reproduction subtest scores were observed in BD-II adolescents. Conclusions The findings of the present study suggested that the disrupted function of corticolimbic system is related with cognitive abnormality of BD-II adolescents. And from the perspective temporal dynamics of brain system, the current study, brain entropy may provide available evidences for understanding the underlying neural mechanism in BD-II adolescents

Authentication of Shenqi Fuzheng Injection via UPLC-Coupled Ion Mobility—Mass Spectrometry and Chemometrics with Kendrick Mass Defect Filter Data Mining

Nearly 5% of the Shenqi Fuzheng Injection’s dry weight comes from the secondary metabolites of Radix codonopsis and Radix astragali. However, the chemical composition of these metabolites is still vague, which hinders the authentication of Shenqi Fuzheng Injection (SFI). Ultra-high performance liquid chromatography with a charged aerosol detector was used to achieve the profiling of these secondary metabolites in SFI in a single chromatogram. The chemical information in the chromatographic profile was characterized by ion mobility and high-resolution mass spectrometry. Polygonal mass defect filtering (PMDF) combined with Kendrick mass defect filtering (KMDF) was performed to screen potential secondary metabolites. A total of 223 secondary metabolites were characterized from the SFI fingerprints, including 58 flavonoids, 71 saponins, 50 alkaloids, 30 polyene and polycynes, and 14 other compounds. Among them, 106 components, mainly flavonoids and saponins, are contributed by Radix astragali, while 54 components, mainly alkaloids and polyene and polycynes, are contributed by Radix codonopsis, with 33 components coming from both herbs. There were 64 components characterized using the KMDF method, which increased the number of characterized components in SFI by 28.70%. This study provides a solid foundation for the authentification of SFIs and the analysis of its chemical composition

High molecular weight hyper-branched PCL-based thermogelling vitreous endotamponades

10.1016/j.biomaterials.2021.121262Biomaterials121262-12126

Effect of Base Oil Polarity on the Functional Mechanism of a Viscosity Modifier: Unraveling the Conundrum of Coil Expansion Model

Viscosity improvement property of a lubricant additive is commonly attributed to polymer coil expansion with increasing temperature, although only some polymer chemistries show conformance to this conceptual mechanism. Herein, we show that the polarity of base oil governs whether this mechanism underlies the action of a viscosity modifier (VM) by combining experimental and computational studies. Poly(butyl methacrylate) (PBMA) dissolved in diethylene glycol diethyl ether (DGDE) or a mixture of DGDE (polar solvent) and squalane (SQ, nonpolar solvent) was used as a model lubricant oil system. Specific viscosity of the polymer solutions measured over a wide range of additive concentrations and temperatures revealed that thickening efficiency of the VM decreased with decreasing base oil polarity. While the VM counteracted temperature-induced thinning of the low polarity base oil, in the polar solvent, the polymer did not enhance the solution viscosity at higher temperatures. Aiming to unravel the molecular mechanism underlying viscosity improvement at elevated temperatures in the different solvent systems, the polymer conformation and size in the dispersing oil were determined by combining solution viscosity, small-angle X-ray scattering measurements, and coarse-grained molecular dynamics simulations. Collectively, the experimental and simulation results show that the coil-swelling model underpins viscosity improvement of the polymer solution in DGDE, and the viscosity of PBMA in DGDE/SQ solution increased with temperature due to polymer association in solution. However, the thermoresponsive behavior of the polymer is more pronounced in the mixed solvent system due to their higher propensity to aggregate at elevated temperatures