The corrosion behavior of P110 casing steel in simulated concrete liquid and simulated annulus fluid was investigated to reveal the corrosion pattern and protective properties of corrosion products in the two environments. Potentiodynamic polarization curves, electrochemical impedance spectroscopy (EIS), Mott–Schottky tests, and electrochemical noise (EN) tests were used to study the corrosion behavior of P110 casing steel in simulated concrete liquid and simulated annulus fluid saturated with CO2. Scanning electron microscopy (SEM) combined with Energy-Dispersive Spectrometer (EDS) mapping was used to characterize the corrosion morphology and elemental distribution of P110 casing steel. The results show that the corrosion resistance of P110 casing steel deteriorates with the increasing immersion days in the simulated annulus fluid, the impedance decreases gradually, and the corrosion-product film shows a loose and porous structure. In the simulated concrete liquid, under the condition of containing a low concentration of Cl−, the protection of the corrosion products gradually increases with the extension of immersion days. With the increasing concentration of Cl− and the extension of immersion days, the electrochemical noise resistance and charge transfer resistance of P110 steel decrease gradually, and the protective property of the corrosion-product film decreases, which is capable of forming steady pitting corrosion.

Carbazole compounds are widely used in determining the direction of petroleum migration, but the effect of thermal maturity on carbazoles is still ambiguity. In this paper, using compaction pyrolysis simulation experiments, artificial mature samples with vitrinite reflectance ( R o ) range from 0.38 to 3.0% were acquired. And the content and composition change characteristics of carbazole compounds were analyzed in coal source rocks. The experimental results showed that thermal maturity controls the generation of a large amount of carbazole compounds in coal rocks. Compared with the low mature stage, the content of carbazole compounds was about 10–100 times higher in the mature stage. With the increasing maturity, in the coal sample, the content of carbazole compounds showed a trend of first increasing and then decreasing. In derivatives of carbazole, the corresponding maturity for the maximum generation of ethylcarbazole (EC), dimethylcarbazole (DMCA), methylcarbazole (MCA), carbazole (CA) and benzocarbazole (BCA) performed the increasing sequence. With the increasing maturity, the relative abundance of 2-MCA, 1,7-DMCA and benzo[a]carbazole increased with the increasing maturity, while 4-MCA, 1,4-DMCA and benzo[c]carbazole gradually decreased. Benzocarbazole ratio [a]/[a] +[ c] varies only in a narrow range 0.36–0.61 in the entire maturity range, suggesting limited maturity dependence. The experimental conclusion provides more theoretical basis for future geochemical analysis using carbazole compounds.

Lipids droplets are organelles that store neutral lipids and are closely related to lipid accumulation. Long chain acyl-coenzyme A synthetase 3 (ACSL3) is a lipid droplet-associated protein mainly distributed in the cell membrane, endoplasmic reticulum, and intracellular lipid droplets, and its distribution depends on cell type and fatty acid supply. ACSL3 is a key regulator of fatty acid metabolism that is closely related to intracellular lipid accumulation, and plays an important role in various pathophysiological processes such as lipid droplet synthesis and lipid metabolism, cellular inflammation, and ferroptosis. This paper mainly reviews the role of ACSL3 in lipid synthesis, ferroptosis, and inflammatory response, with focus on the mechanism of its role in lipid accumulation in atherosclerosis, and provides new ideas for exploring potential therapeutic targets in atherosclerotic diseases.

Superoxide dismutase (SOD) is an antioxidant enzyme with multiple metal cofactors that can specifically clear reactive oxygen species (ROS), which plays an important role in a variety of ultraviolet-induced lesions. Therefore, SOD has the anti-ultraviolet radiation effect. The objective of this study was to compare the differences in the anti-ultraviolet radiation effect of SOD with distinct metal cofactors: Cu/Zn-SOD and Mn-SOD. SOD was first purified using hydrophobic interaction chromatography and ion-exchange chromatography. Second, the Methylthiazolyldiphenyl-tetrazolium bromide method and cell senescence kits were used to study the protective effect of SOD on ultraviolet-induced cell damage. Finally, the protective effect of SOD on ultraviolet -induced skin damage was histopathologically evaluated, and the expression levels of malondialdehyde (MDA) and matrix metalloproteinases (MMPs) in tissues were detected. The results showed that Cu/Zn-SOD was superior to Mn-SOD in promoting cell proliferation, alleviating cell damage, protecting skin structure, and regulating the expression levels of MDA and MMPs, and it has no side effects. In conclusion, Cu/Zn-SOD had a better anti-ultraviolet radiation effect than Mn-SOD, and it can be used in anti-aging and anti-ultraviolet skin-care products.

Abstract Carbazole compounds are widely used in determining the direction of hydrocarbon migration, but the effect of thermal maturity on carbazoles remains unclear. In this paper, using compaction pyrolysis simulation experiments, artificial mature samples with vitrinite reflectance (Ro) range from 0.38–3.0% were acquired. And the content and composition change characteristics of carbazole compounds were analyzed. The results showed that thermal maturity had a significant influence on the content of carbazole compounds. Compared with the low mature stage, the content of carbazole compounds was about 10 to 100 times higher in the mature stage. With the increasing maturity, in the coal sample, the content of carbazole compounds showed a trend of first increasing and then decreasing. The formation of carbazole compounds was later than generation of hydrocarbon, suggesting carbazoles mainly produced by the thermal degradation of kerogen. In derivatives of carbazole, the corresponding maturity for the maximum generation of ethylcarbazole (EC), dimethylcarbazole (DMCA), methylcarbazole (MCA), carbazole (CA) and benzocarbazole (BCA) performed the increasing sequence. The timing of reaching the maximum content of carbazole compounds is related to the number and type of substituents. The more substituents and longer branches result earlier formation peak. With the increasing maturity, the relative abundance of 2-MCA, 1,7-DMCA and benzo[a]carbazole increased with the increasing maturity, the relative abundance of 1,5-DMCA remained almost unchanged, while 4-MCA, 1,4-DMCA and benzo[c]carbazole gradually decreased. The commonly used parameters as indicators of hydrocarbon migration were greatly affected by maturity. Therefore, when using carbazole compounds as geochemical parameters, it is necessary to fully consider the impact of thermal maturity on them, and avoid transport fractionation or other factors masking the true maturity effect.

在基于相干光时域反射计的分布式光纤温度与应变传感原理的基础上,对不同频率入射光的后向瑞利散射信号在频域上的相关特性进行了分析。用后向瑞利散射的离散模型来说明后向瑞利散射信号在传感光纤中传播的原理,用MATLAB软件对COTDR（相干光时域反射）过程进行了仿真和分析,对不同脉冲宽度的入射信号的功率及相关特性进行了分析研究。结果表明,输入脉冲宽度与频域相关带宽成反比,即传感位置精度与温度或应变精度成反比。

Apelin is an endogenous peptide that can activate G protein-coupled receptor—putative receptor protein related to the angiotensin receptor AT1(APJ).Activation of apelin/APJ system can increase cardiac contractility and decrease blood pressure.It can promote angiogenesis and is closely related to the development of tumor.In digestive system,it can regulate insulin secretion as new adipokine.It has roles in respiratory system,urinary system,and endocrine and reproductive system.It can aslo regulate the release of pituitary hormones and play a role in water-electrolyte metabolism in the central nervous system.Apelin/APJ system is expected to be a therapeutic target for heart failure,hypertension,tumor,obesity related diseases,etc.

Objective To study the expression of deleted in colorectal carcinoma(DCC)protein and its relationship to Bcl-2 and Bax in human colorectal carcinoma.Methods Seventy-four cases of primary carcinoma were studied by streptavidin peroxidase immunohistochemical technique and image analysis.Results Negative rate of DCC protein was 54.1%(40/74),DCC expression had significantly difference with degree of the differentiation(P=0.002)and Dukes stage(P=0.042);Positive rate of Bcl-2 protein was 60.8%(45/74),Bcl-2 expression had significantly difference indifferent Dukes stage(P=0.032)and lymphoma metastasis(P0.001);Positive rate of Bax protein was 48.6 %(36/74),no correlation was found between Bax expression and the clinical pathological parameters of colorectal carcinomas.DCC expression significantly positively correlated with Bax(r=0.296,P0.01),and negatively correlated with Bcl-2(r=-0.201,P0.05).Conclusion Loss or downregulation of DCC protein expression is a frequent event,which possibly plays a role in colorectal carcinoma by upregulating Bcl-2 protein and downregulating Bax protein.