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Copyright of China Mining Magazine is the property of China Mining Magazine Co., Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Functional Materials / Gongneng Cailiao is the property of Chongqing Functional Materials Periodical Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: Investigating the protective effect and mechanisms of downregulating miR-223 expression on the myocardium of mice with septic cardiomyopathy (SCM). Methods: Using a random number table, 27 male SPF C57BL/6 mice aged 8-10 weeks were allocated into different groups: SCM model groups at different time points (0 h, 6 h, 12 h, 18 h, 24 h), Normal group, SCM group, miR-223 antagomir NC group, and miR-223 antagomir group, with 3 mice in each group. The SCM mouse model was established by intraperitoneal injection of lipopolysaccharide (LPS) at a dose of 15 mg/kg. The miR-223 antagomir NC group and miR-223 antagomir group received consecutive tail vein injections of miR-223 antagomir NC and miR-223 antagomir, respectively, for 3 days before modeling. Reverse transcription-polymerase chain reaction (RT-PCR) was used to study the expression of miR-223 in the myocardial tissue of mice in different time point groups of the SCM model. Hematoxylin-eosin (HE) staining was performed to observe the myocardial pathological changes in the Normal group, SCM group, miR-223 antagomir NC group, and miR-223 antagomir group. Enzyme-linked immunosorbent assay (ELISA) was used to measure the levels of cTnI, BNP, CK-MB, IL-6, IL-1β, and TNF-α in mouse serum in the Normal group, SCM group, miR-223 antagomir NC group, and miR-223 antagomir group, and correlation analysis was conducted. Results: In the SCM model groups at different time points, the expression level of miR-223 in the myocardial tissue gradually increased with the extension of stimulation time. Compared to the Normal group, mice in the SCM group, miR-223 antagomir NC group, and miR-223 antagomir group exhibited varying degrees of myocardial damage. The expression levels of cardiac injury markers cTnI, BNP, CK-MB, and inflammatory factors IL-6, IL-1β, and TNF-α in serum were elevated, and the differences were statistically significant (P＜0.05). When compared to the SCM group, there were no significant differences in various indicators between the miR-223 antagomir NC group (P＞0.05). In the miR-223 antagomir group, the degree of pathological damage in the myocardial tissue was reduced, and the levels of cardiac injury markers cTnI, BNP, CK-MB, and inflammatory factors IL-6, IL-1β, and TNF-α decreased, with statistically significant differences (P＜0.05). The results of correlation analysis showed that the expression of miR-223 in mice was positively correlated with the expression of cardiac injury markers cTnI, BNP, CK-MB, and inflammatory factors IL-6, IL-1β, and TNF-α. Conclusion: Downregulation of miR-223 expression can provide protection to the myocardium of SCM mice by alleviating the inflammatory response. [ABSTRACT FROM AUTHOR]

Copyright of Atomic Energy Science & Technology is the property of Editorial Board of Atomic Energy Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Atomic Energy Science & Technology is the property of Editorial Board of Atomic Energy Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Geoscientica Sinica is the property of Acta Geoscientica Sinica Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Packaging materials can be widely used to protect food products from contamination while in storage. In this study, the sterilization process was simulated and optimized using hydrogen peroxide (H2O2) solution atomized aerosol on the inner surface of a gable-top carton. The efficacy of hydrogen peroxide solution was evaluated with the different size boxes in the sterilization process. The process, principle, and influencing factors of solution atomization were analyzed using the sterilization process of hydrogen peroxide in the packaging materials of the roof box packaging machine. Finally, the optimal scheme was provided for uniform sterilization. The Euler-Lagrange model was selected to simulate the atomization process of an air-assisted nozzle. A comparison was also made to clarify the effects of atomization times and air pressure on the atomization quality. Specifically, the Droplet Sauter average diameter decreased, whereas, the atomization distance increased with the increase of atomization time. There was an increase in the spray distance, angle, and range, with the increase in air pressure. As such, a more uniform liquid atomization was achieved during this time. The different simulation conditions were compared with the actual spray debugging, in order to observe the spray shape. At the same time, the spray angle, and spray distance were measured under different conditions. It was found that the errors between the measured and the simulated values were within 15%, indicating the excellent performance of the simulation. The air-assisted spray model was then applied to the sterilization process, combined with the structural simulation of gable-top cartons with different specifications. There was a significant effect of carton specifications on the distribution of atomized droplets, especially in the bottom position. Specifically, the low height of the 250 mL carton led to a large number of droplets gathering on the bottom surface of the carton. There was a more outstanding increase in the spray height, and the atomized solution escape. By contrast, the solution aggregation of the bottom surface was reduced for the more uniform distribution of the side solution. Therefore, the optimal spray height was achieved for uniform and safe sterilization, indicating the higher concentration of H2O2 residues on the bottom surface. In 1 000 mL cartons, almost no droplets were attached to the bottom end and bottom surface, due to the higher height than that of the rest. In this case, the distribution of the liquid film was more uniform, whereas, the higher thickness was obtained to increase the atomizing air pressure. Therefore, the optimal air pressure was recommended to appropriately increase for better sterilization. More importantly, there was insufficient bottom of the carton sterilization. The numerical model of hydrogen peroxide sol sterilization can be expected to combine with different process parameters, thereby to output the simulation for higher sterilization efficiency. At the same time, the process parameters were optimized for the different cartons. The finding can also provide a strong reference for the process design of aerosol sterilization on the packaging materials, particularly diversified size roof carton filling machine in the future. [ABSTRACT FROM AUTHOR]

A microbial challenge test was proposed to optimize the sterilization process for high efficiency of packaging materials in roof-carton aseptic filling. Bacillus stearothermophilus spores were evenly coated on the inner surface of the clean roof-carton packaging materials. A filling machine was then used to sterilize the packing material. The plate counting and the Most Probable Number (MPN) method were selected to recycle the residual spores on the surface of the sterilized material. The sterilization efficiency was characterized by the Log Cycle Reduction (LCR) of inoculated spore. A single factor test was carried out to determine the effects of hydrogen peroxide solution concentration, vaporized hydrogen peroxide vapor temperature, air pressure of vaporization heat, and UV irradiation time on the sterilization efficiency. A response surface test was designed for the significant variable conditions, according to the Box-Behnken principle. As such, a quadratic polynomial regression model was established for the sterilization efficiency of packaging materials. The aseptic filling machine was normally required that the sterilization effect of packaging materials was up to a 4-lg reduction in the number of inoculated microorganisms. The LCR value was calculated as 5 using the MPN statistical method. The optimal process parameters were determined to consider the comprehensive influencing factors, such as the design cost of mechanical structure, tolerance temperature of packaging materials, and hydrogen peroxide consumption. A concentration test of hydrogen peroxide was also utilized to detect the residual concentration in the package after sterilization. A hot-air drying was then used to adjust the process parameters for the standard residues of hydrogen peroxide. The results show that the sterilization efficiency of packaging materials in the filling machine dramatically improved with the increase of the parameters, among which the concentration of hydrogen peroxide solution, the steam temperature of hydrogen peroxide, and ultraviolet radiation time posed a significant effect on the sterilization efficiency, whereas, the vaporization heat air pressure was no significant effect on the sterilization efficiency. Therefore, a quadratic polynomial regression of sterilization efficiency was obtained from the response surface test, where the concentration of hydrogen peroxide solution, the temperature of hydrogen peroxide vapor, and UV irradiation time were selected as the variable conditions. The significant order of sterilization efficiency was then ranked as the hydrogen peroxide solution concentration > hydrogen peroxide steam temperature > ultraviolet irradiation time. Once the LCR sterilization of packaging material was required as 5, the optimal process parameters were the 8% hydrogen peroxide solution concentration, and 230 ℃ hydrogen peroxide vapor temperature. The 104 CFU spore-inoculated roof carton sample was tested 20 times, and the packaging material was completely sterilized, indicating the reliable regression model for the influence of various factors on the LCR value. This finding can provide the technical basis for the sterilization process of packaging materials during aseptic filling. [ABSTRACT FROM AUTHOR]

At the preliminary stage of mass spectrometry (MS) technology development, it was mainly applied to determine the nuclear industry related inorganic isotope abundance. With the rapid development of nuclear industry, MS has been employed to analyze the impurities in nuclear fuel and nuclear materials, burnup of nuclear fuels, and nuclides from high-temperature gas-cooled reactor (HTGR). The study mainly discussed the basic principles, application, and the research method’s advantages and disadvantages of inorganic mass spectrometry applied to analysis of tritium from HTGR, trace amounts of plutonium and neptunium and 14C in its spent fuel. The application and R&D status of gas isotope mass spectrometer (GIMS), inductively coupled plasma mass spectrometer (ICP-MS), laser resonance ionization mass spectrometry (LRIMS), and accelerator mass spectrometer (AMS) at domestic and abroad were introduced, and problems of the instruments, application and development tendency were pointed out. The low resolution GIMS has the disadvantages of strict conditions, limited scope of application, and complex error during the analysis of hydrogen isotopes, while the high resolution GIMS is overcome the disadvantages of low resolution GIMS, and able to realize the rapid and accurate analysis with low determinative error. However, high resolution GIMS is embargoed due to the special military applications, and need to independently develop it by China. The disadvantages of ICP-MS such as poor anti-interference performance, low resolution, analyze by destroy the simple, and severe inhibition effects for space charge leads its low accuracy, which limit the application in nuclear field. Although there are prominent advantages for LRIMS, it still has poor reproducibility of laser source as one of laser MS, and need further research. China is developing rapidly in import and independent R&D of AMS, but there are many problems in the spent fuel and other nuclear industry related application and R&D field, such as low sensitivity and limited determination of special or several nuclides. The main application of AMS with gas ion source is determination of 14C, and the sensitivity reaches to 10-16. Until now, the R&D of gas ion source for AMS hasn’t be reported in China. This study discussed future developing direction of relevant mass spectrometry and outlined the potential solutions. In order to improve the efficiency of MS application on HTGR research, it is urgent to develop the easy operating intelligent instruments with small volume and simple structure. [ABSTRACT FROM AUTHOR]