Phase Transformation Path in Aluminum Under Ramp Compression; Simulation and Experimental Study

Identifying structure phase transformation path is essential but challenging in plastic deformation under high-pressure high-strain rate experiments. In this paper, we adopt a framework based on non-equilibrium molecular dynamics and virtual diffraction to reproduce the phase transformation event observed in laser-driven ramp compression. Our simulation results reveal the detailed phase transformation pathway with atomic-level deformation physics while the simulated stress-density response and virtual diffraction patterns match the experimental observation with great accuracy.

Attenuated Structural Transformation of Aconitine during Sand Frying Process and Antiarrhythmic Effect of Its Converted Products

The transformation pathways of diterpenoid alkaloids have been clarified in the boiling and steaming process. Aconitine, a famous diterpenoid alkaloid, is successively transformed into benzoylaconine and aconine during the processes of boiling and steaming, but the transformation pathway remains to be determined in the sand frying process. The present study aims at investigating the transformation pathways of aconitine in the process of sand frying, as well as assessing the cardiotoxicity and antiarrhythmic activity of aconitine and its converted products. The parameters of temperature and time for the structural transformation of aconitine were confirmed by HPLC. The converted products were further separated and identified by column chromatography, NMR, and HR-ESI-MS. Furthermore, by observing the lead II electrocardiogram (ECG) changes in rats under an equivalent dose, the cardiotoxicity of aconitine and its converted products were compared. Ultimately, the antiarrhythmic effect of the converted products was investigated by employing the model of aconitine-induced arrhythmia. Consequently, the structure of aconitine was converted when processed at 120°C–200°C for 1–40 min. Two diterpenoid alkaloids, a pair of epimers, namely, pyroaconitine and 16-epi-pyroaconitine, were further isolated from processed aconitine. 0.03 mg/kg aconitine induced arrhythmias in normal rats, while the converted products did not exhibit arrhythmias under an equal dose. In the antiarrhythmic assay, 16-epi-pyroaconitine could dose-dependently delay the onset time of VPB, reduce the incidence of VT, and increase the arrhythmia inhibition rate, demonstrating comparatively strong antiarrhythmic activity. Conclusively, compared with the prototype compound aconitine, the converted products exhibited lower cardiotoxicity. Further investigations on the cardiotoxicity indicated that pyroaconitine with β configuration had a stronger cardiotoxicity than 16-epi-pyroaconitine with α configuration. Furthermore, 16-epi-pyroaconitine could antagonize the arrhythmogenic effect caused by the prototype compound aconitine; the antiarrhythmic effect of 16-epi-pyroaconitine was stronger than lidocaine and propafenone, which had the potential to be developed as antiarrhythmic drugs.

High Concentration Organic Wastewater with High Phosphorus Treatment by Facultative MBR

Phosphorus is one of the main factors causing water eutrophication, and the traditional phosphorus removal process causes phosphorus-rich sludge pollution. The facultative MBR process uses phosphate-reducing bacteria to convert phosphate into directly recyclable gaseous phosphine to solve this malpractice and make sewage become a new phosphorus resource. In order to investigate the phosphorus removal efficiency and the mechanism under facultative conditions, run the facultative MBR reactor for 30 days. The COD value, phosphate concentration, and phosphine yield were measured, and the changes of sludge metabolic pathway abundance and community composition in different periods were detected. According to the measurement, the maximum phosphorus removal efficiency is 43.11% and the maximum yield of phosphine is 320 μg/m3 (measured by the volume of sewage). Combined with thermodynamic analysis, the microbial mechanism of the reactor was proposed, and the possible transformation pathway of phosphorus was analyzed. At last, changes the phosphorus removal process from the ‘removal type’ to the ‘recycling type’.

Transcriptome Analysis of Related-genes to MeJA Treatment Metabolite Synthesis in Hairy Roots of Broccoli (Brassica oleracea L. var. Italic Planch)

Hairy roots obtained by infecting broccoli (Brassica oleracea L. var. Italic Planch) leaves with Agrobacterium rhizogenes (ATCC15834) had the characteristics of phytohormone autonomy, genetic stability and can produce a large amount of anti-cancer substance Sulforaphane (SF) and SF biosynthetic precursors substance Glucoraphanin (GRA). The production of SF in hairy roots of broccoli increased significantly under the induction of exogenous signal molecule Methyl jasmonate (MeJA). However, the molecular mechanism of MeJA treatment hairy roots of broccoli have not been reported. In this study, the optimal concentration of MeJA for having treatment broccoli hairy roots were selected based on the yield of GRA and SF. After grew 18 days, broccoli hairy roots were treated with 10 mmol/L MeJA for 0, 3, 6, 9 and 12 h respectively. Compared with 0 h, the yields of GRA and SF increased under other treatments. The highest yield of GRA and SF was noted at 9 h, which were 2.22-fold and 1.74-fold of 0 h, respectively. Broccoli (Brassica oleracea L. var. botrytis L) as reference genome, and 1195 co-differentially expressed genes (DEGs) at 0, 3, 6, 9 and 12 h was observed under treatment 10 mmol/L MeJA, which there were 3,826 down-regulated and 574 up-regulated genes. The six key genes that regulated Glucosinolates (GLS) synthesis, MAM1, CYP79B1, CYP83B1, UGT74B1, and FMOGS-OX5, were up-regulated at 0 and 3 h, and down-regulated at the rest of the time; BCAT2 was up-regulated at 6, 9, 12 h, and at 0, 3 h expression was down-regulated, transcription factors MYB34 and MYB122 were up-regulated at 3 h, and down-regulated at other time points, MYB51 was up-regulated at 0, 3 h and down-regulated at 6, 9, 12 h. The pathway diagram of GRA biosynthesis and transformation pathway in broccoli hairy roots treatment by MeJA simulated, and the molecular mechanis0m of GRA biosynthesis and SF accumulation in broccoli hairy roots under MeJA treatment were revealed.

Universal phase dynamics in VO2 switches revealed by ultrafast operando diffraction

Understanding the pathways and time scales underlying electrically driven insulator-metal transitions is crucial for uncovering the fundamental limits of device operation. Using stroboscopic electron diffraction, we perform synchronized time-resolved measurements of atomic motions and electronic transport in operating vanadium dioxide (VO2) switches. We discover an electrically triggered, isostructural state that forms transiently on microsecond time scales, which is shown by phase-field simulations to be stabilized by local heterogeneities and interfacial interactions between the equilibrium phases. This metastable phase is similar to that formed under photoexcitation within picoseconds, suggesting a universal transformation pathway. Our results establish electrical excitation as a route for uncovering nonequilibrium and metastable phases in correlated materials, opening avenues for engineering dynamical behavior in nanoelectronics.