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Objective To explore the biomarkers and potential mechanisms of chronic restraint stress-induced myocardial injury in hyperlipidemia ApoE-/- mice. Methods The hyperlipidemia combined with the chronic stress model was established by restraining the ApoE-/- mice. Proteomics and bioinformatics techniques were used to describe the characteristic molecular changes and related regulatory mechanisms of chronic stress-induced myocardial injury in hyperlipidemia mice and to explore potential diagnostic biomarkers. Results Proteomic analysis showed that there were 43 significantly up-regulated and 58 significantly down-regulated differentially expressed proteins in hyperlipidemia combined with the restraint stress group compared with the hyperlipidemia group. Among them, GBP2, TAOK3, TFR1 and UCP1 were biomarkers with great diagnostic potential. KEGG pathway enrichment analysis indicated that ferroptosis was a significant pathway that accelerated the myocardial injury in hyperlipidemia combined with restraint stress-induced model. The mmu_circ_0001567/miR-7a/Tfr-1 and mmu_circ_0001042/miR-7a/Tfr-1 might be important circRNA-miRNA-mRNA regulatory networks related to ferroptosis in this model. Conclusion Chronic restraint stress may aggravate myocardial injury in hyperlipidemia mice via ferroptosis. Four potential biomarkers are selected for myocardial injury diagnosis, providing a new direction for sudden cardiac death （SCD） caused by hyperlipidemia combined with the restraint stress.

The process of the bubble accelerating expansion plays an important role in underwater explosion, which determines the energy output and affects the bubble oscillation subsequently. In this paper, we treated the accelerating expansion cut-off state as the critical state and applied it to the division of the expansion work, energy output, and the initial condition for bubble oscillation. It found that the Rayleigh–Plesset equation was considered appropriate to investigate the roles of underwater explosion bubble accelerating expansion cut-off state compared to the Keller equation, volume acceleration model (VAM), and pu-diagram method, and that was verified by the experimental data. Furthermore, the influence of the critical state on the expansion work and energy distribution in the accelerating expansion process was clarified, the larger critical relative volume leads to higher expansion work efficiency and total expansion work, and the shorter critical time increases the portion of the shock wave energy in the expansion work. Our finding provides a method to study the initial condition for the bubble oscillation, and that has significance in the energy output research. [ABSTRACT FROM AUTHOR]

There is confinement of a bubble that provides a long time for the afterburn reaction of aluminum (Al) additives when aluminized explosives explode in water, and the information of the reaction is reflected by the dynamic behaviors of a bubble. In this study, the energy partition of RDX-based aluminized explosives with different Al content was obtained in an underwater explosion experiment, and the influence of an afterburn reaction on the bubble accelerating expansion, decelerating expansion, and contraction was revealed. It found that the pressure in these stages was changed with different Al content, leading to the variation in the reaction process of Al that releases the afterburn energy. Based on the analysis of the afterburn reaction of full stages, the afterburn reaction process in accelerating expansion was in agreement with that in metal acceleration of a cylinder test and the afterburn reaction mechanism in high pressure was validated; the afterburn reaction characteristics in decelerating expansion and contraction stage were obtained and the reaction mechanism of low pressure was developed. This research is significant to optimize the contribution of the afterburn reaction to explosion performance of aluminized explosives. [ABSTRACT FROM AUTHOR]

The initial states and pressure of detonation products in a bubble have a great impact on bubble pulsation in underwater explosions; particularly, the initial accelerated expansion of a bubble can determine the energy distribution. The energy output and distribution of explosives were obtained on the basis of the underwater explosion experiment in this paper. To study the process of bubble pulsation and energy output, we proposed a gas equation of state (EOS) combining the pvk form, Jones–Wilkins–Lee (JWL) EOS, and the initial states of a bubble to take the effects of the initial bubble pressure and detonation products state transformation into account; furthermore, the bubble radius, velocity, and acceleration vs time were obtained through the Rayleigh–Plesset equation under our experimental condition. The differences of bubble behaviors were compared by adopting the JWL EOS and a polytropic EOS with k = 3. The results showed that the initial bubble pressure and detonation products state transformation influence the accelerating expansion and the subsequent bubble oscillation, respectively. Subsequently, comparisons of the energy output and distribution for different gas EOSs showed that the initial shock wave energy for the JWL EOS was underestimated in accelerating expansion, and the bubble energy was overestimated using the polytropic EOS for k = 3; the obtained energy output and distribution had a better agreement with experimental data when adopting the improved gas EOS. In addition, the energy distribution was determined before the detonation products turned to the explosion gas state in initial expansion based on the relationship of the accelerating expansion characteristics and the initial shock wave energy generation. The research has a great significance to reveal the mechanism of bubble pulsation in underwater explosions. [ABSTRACT FROM AUTHOR]

The incidence of tobacco bacterial wilt, caused by Ralstonia solanacearum, is significantly affected by temperature. However, the effect of temperature on the metabolism of carbon and amino acid substrates used in phenotypic characterization of R. solanacearum is still unknown. In order to evaluate the effect of temperature on metabolic phenotypes, the phenotypes of the pathogen were characterized and compared with a BIOLOG Phenotype MicroArray (PM) at 20, 24, 30 and 35°C. The results showed that phenotypes of R. solanacearum at all four temperatures were mostly similar. However, a few differences were observed, such as in the ability to metabolize L-proline. The bacterium was able to metabolize more than 30% of the tested carbon sources and 83% of amino acid nitrogen substrates. For carbon sources, the most informative utilization patterns were organic acids and carbohydrates; for nitrogen sources, the most informative were amino acids. The bacterium showed much higher metabolic ability at 35°C than at 20, 24 and 30°C, and was more adaptable to osmolytes and pH environments at 30 and 35°C than at 20 and 24°C. It presented no deaminase activity, had high decarboxylase activity at 35°C and low decarboxylase activity at 20 and 24°C. When the phenotypic data were subjected to comparative phenomic analyses, temperature did have a significant effect on the characterization of the pathogen. The results provide clues to possible new methods to manage tobacco bacterial wilt. [ABSTRACT FROM AUTHOR]