ADAPTABILITY OF LASER TEXTURED LINER TO THE EFFECTS OF METHANOL DILUTING OIL ON TRIBOLOGICAL PROPERTIES

Jia He Kun,Xu Bo,Yin Bifeng,Jiang Yuhao,Hu Nanrong 한국자동차공학회 2022 International journal of automotive technology Vol.23 No.2

With the increase of methanol diluting lubrication oil, the dynamic viscosity of the mixture presents a downward trend, the total acid number grows while the total base number declines, and the corrosion degree of copper strip upgrades, which indicates that methanol dilution has negative effects on lubrication and anti-corrosion performance of oil. According to ball-on-plate friction test results, the friction coefficient and surface wear of this pair increase in turn with the rising methanol dilution rate, which tends to deteriorate the tribological performance of key friction pairs in methanol engine. After laser surface texturing cylinder liner, the friction coefficient of ring/liner pair is reduced, and the anti-friction effect is enhanced with the rising methanol dilution rate, because the oil storage capacity of textured micro-dimples on liner surface can improve the lubrication of ring/liner pair and reduce asperity contact. Moreover, the micro-dimples can store debris generated in the reciprocating friction process of this pair, so as to alleviate surface wear caused by abrasive wear, and improve the wear resistance of cylinder liner. Therefore, laser texturing cylinder liner can compensate the deterioration of friction and wear performance of ring/liner pair caused by methanol diluting oil with good lubrication adaptability.

Betulin Targets Lipin1/2-Meidated P2X7 Receptor as a Therapeutic Approach to Attenuate Lipid Accumulation and Metaflammation

( Jia-yi Dou ),( Yu-chen Jiang ),( Zhong-he Hu ),( Kun-chen Yao ),( Ming-hui Yuan ),( Xiao-xue Bao ),( Mei-jie Zhou ),( Yue Liu ),( Zhao-xu Li ),( Li-hua Lian ),( Ji-xing Nan ),( Yan-ling Wu ) 한국응용약물학회 2022 Biomolecules & Therapeutics(구 응용약물학회지) Vol.30 No.3

The present study focused on the potential mechanism of betulin (BT), a pentacyclic triterpenoid isolated from the bark of white birch (Betula pubescens), against chronic alcohol-induced lipid accumulation and metaflammation. AML-12 and RAW 264.7 cells were administered ethanol (EtOH), lipopolysaccharide (LPS) or BT. Male C57BL/6 mice were fed Lieber-DeCarli liquid diets containing 5% EtOH for 4 weeks, followed by single EtOH gavage on the last day and simultaneous treatment with BT (20 or 50 mg/kg) by oral gavage once per day. In vitro, MTT showed that 0-25 mM EtOH and 0-25 μM BT had no toxic effect on AML-12 cells. BT could regulate sterolregulatory-element-binding protein 1 (SREBP1), lipin1/2, P2X7 receptor (P2X7r) and NOD-like receptor family, pyrin domains-containing protein 3 (NLRP3) expressions again EtOH-stimulation. Oil Red O staining also indicated that BT significantly reduced lipid accumulation in EtOH-stimulated AML-12 cells. Lipin1/2 deficiency indicated that BT might mediate lipin1/2 to regulate SREBP1 and P2X7r expression and further alleviate lipid accumulation and inflammation. In vivo, BT significantly alleviated histopathological changes, reduced serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) and triglyceride (TG) levels, and regulated lipin1/2, SREBP1, peroxisome proliferator activated receptor α/γ (PPARα/γ) and PGC-1α expression compared with the EtOH group. BT reduced the secretion of inflammatory factors and blocked the P2X7r-NLRP3 signaling pathway. Collectively, BT attenuated lipid accumulation and metaflammation by regulating the lipin1/2-mediated P2X7r signaling pathway.

Age of Diagnosis of Breast Cancer in China: Almost 10 Years Earlier than in the United States and the European Union

Song, Qing-Kun,Li, Jing,Huang, Rong,Fan, Jin-Hu,Zheng, Rong-Shou,Zhang, Bao-Ning,Zhang, Bin,Tang, Zhong-Hua,Xie, Xiao-Ming,Yang, Hong-Jian,He, Jian-Jun,Li, Hui,Li, Jia-Yuan,Qiao, You-Lin,Chen, Wan-Qin Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.22

Background: The study aimed to describe the age distribution of breast cancer diagnosis among Chinese females for comparison with the United States and the European Union, and provide evidence for the screening target population in China. Materials and Methods: Median age was estimated from hospital databases from 7 tertiary hospitals in China. Population-based data in China, United States and European Union was extracted from the National Central Cancer Registry, SEER program and GLOBOCAN 2008, respectively. Age-standardized distribution of breast cancer at diagnosis in the 3 areas was estimated based on the World Standard Population 2000. Results: The median age of breast cancer at diagnosis was around 50 in China, nearly 10 years earlier than United States and European Union. The diagnosis age in China did not vary between subgroups of calendar year, region and pathological characteristics. With adjustment for population structure, median age of breast cancer at diagnosis was 50~54 in China, but 55~59 in United States and European Union. Conclusions: The median diagnosis age of female breast cancer is much earlier in China than in the United States and the European Union pointing to racial differences in genetics and lifestyle. Screening programs should start at an earlier age for Chinese women and age disparities between Chinese and Western women warrant further studies.

RESEARCH ON THE INFLUENCE OF HYDROGEN AND OXYGEN FUEL OBTAINED FROM WATER ELECTROLYSIS ON COMBUSTION STABILITY OF SHALE GAS ENGINES

Liu Shuai,Wang Zhong,Jia He Kun,Chen Lin 한국자동차공학회 2019 International journal of automotive technology Vol.20 No.1

Hydrogen and oxygen fuel obtained from water electrolysis mainly contains H2 and O2, usually abbreviated to HHO. The compositional characteristics of HHO were analyzed by gas chromatography-mass spectrometry (GC-MS). The influence of HHO on the combustion process in the cylinder was discussed. The change law of the maximum combustion pressure and the variation of the crank angle were studied, and the nonlinear dynamic process of the combustion process was revealed. The research indicated that the cylinder pressure increased after mixing HHO and that the period of flame development and rapid combustion was shortened. With the increase in HHO content, the cycle-by-cycle variations were reduced, combustion stability improved, partial-burning and other abnormal combustion phenomena improved, the phase space trajectory distribution gradually intensified, and the engine combustion process of the cyclical variation increased.

Microscopic Mechanisms and Acoustic Emission Characteristics of Sandy Mudstone under Different Water Saturations

Xiao-ming Sun,Fu-kun Shi,Ming-qun Zhu,Jia-xu Ding,Lin-sen He,Zhi-hu Li,Tong Zhang,Cheng-yu Miao 대한토목학회 2024 KSCE Journal of Civil Engineering Vol.28 No.1

In order to study the damage mechanism of surrounding rocks under water-rock coupling, an experimental study on the microscopic law of water absorption and mechanics of sandy mudstone was carried out in the sandy mudstone stratum of Wanfu coal mine in Shandong, China. The results indicate that the strength of sandy mudstone exhibits three stages of relative softening, rapid softening, and decelerated softening. The speed of water molecules entering the microscopic pore structure was analyzed based on the percentage of water molecules in the pore structure. The acoustic emission energy release process is divided into energy accumulation stage, stable release stage and intense release stage. With the increase of water content saturation,  (Spectral width of the multifractal spectrum) tends to decrease and the distribution of events is gradually uniform. The action of water gradually expands and penetrates the cracks and pores inside the sandy mudstone, which makes f (Frequency of occurrence of the signal) change from negative to positive values.

Synergistic Effect of Bone Marrow-Derived Mesenchymal Stem Cells and Platelet-Rich Plasma in Streptozotocin-Induced Diabetic Rats

( Zhen Zhen Lian ),( Xiao Jing Yin ),( Hua Li ),( Li Li Jia ),( Xiu Zhen He ),( Yong Bo Yan ),( Nai Hua Liu ),( Ka Yiu Wan ),( Xiao Kun Li ),( Shao Qiang Lin ) 대한피부과학회 2014 Annals of Dermatology Vol.26 No.1

Background: Diabetic wounds are a major clinical challenge, because minor skin wounds can lead to chronic, unhealed ulcers and ultimately result in infection, gangrene, or even amputation. Studies on bone marrow derived mesenchymal stem cells (BMSCs) and a series of growth factors have revealed their many benefits for wound healing and regeneration. Platelet-rich plasma (PRP) may improve the environment for BMSC development and differentiation. However, whether combined use of BMSCs and PRP may be more effective for accelerating diabetic ulcer healing remains unclear. Objective: We investigated the efficacy of BMSCs and PRP for the repair of refractory wound healing in a diabetic rat model. Methods: Forty-eight rats with diabetes mellitus induced by streptozotocin were divided into four groups: treatment with BMSCs plus PRP, BMSCs alone, PRP alone, phosphate buffered saline. The rate of wound closure was quantified. A histopathological study was conducted regarding wound depth and the skin edge at 7, 14, and 28 days after surgery. Results: Wound healing rates were significantly higher in the BMSC plus PRP group than in the other groups. The immunohistochemistry results showed that the expression of platelet/endothelial cell adhesion molecule 1, proliferating cell nuclear antigen, and transforming growth factor-β1 increased significantly in the BMSC plus PRP group compared to the other treatment groups. On day 7, CD68 expression increased significantly in the wounds of the BMSC plus PRP group, but decreased markedly at day 14 compared to the controls. Conclusion: The combination of BMSCs and PRP aids diabetic wound repair and regeneration. (Ann Dermatol 26(1) 1∼10, 2014)