Computer simulation of the nonlinear static behavior of axially functionally graded microtube with porosity

Li, Xiaohuan,Wang, Tian,Liu, Fang,Zhu, Zhiwen Techno-Press 2021 Advances in nano research Vol.11 No.4

Static analysis of microstructures, including bending and buckling, is widely practiced in the fabrication and creation of applications such as actuation, sensing, and energy recovery. This article aims to inquire about the static behavior of non-uniform and imperfect microtubes through a numerical solution. Based on the modified couple stress theory, the first-order shear deformation theory and Von-Karman nonlinear theory, and employing the energy conservation method, the linear and nonlinear governing equations are derived. The porosity-dependent material in both ceramic and metal phases makes the functionally graded materials which are varied along tube length, moreover, cross-sections are also considered uniform and nonuniform via three valuable functions. Finally, the linear and nonlinear equations are solved utilizing the generalized differential quadrature method (GDQM) coupled with the numerical iteration method.

The mechanism of mesna in protection from cisplatin-induced ovarian damage in female rats

Xiaohuan Li,Shu Yang,Xiangyang Lv,Haimei Sun,Jing Weng,Yuanjing Liang,Deshan Zhou 대한부인종양학회 2013 Journal of Gynecologic Oncology Vol.24 No.2

Objective: Cisplatin is a widely used chemotherapeutic agent in the treatment of cancers in clinic; but it often induces adverse effects on ovarian functions such as reduced fertility and premature menopause. Mesna could attenuate the cisplatin-induced ovarian damages; however, the underlying mechanism is still unknown. This study aimed to figure out the underlying mechanism of the protection of mesna for ovaries against cisplatin therapy in cancers. Methods: We performed female adult Sprague-Dawley rats into normal saline control (NS), low-dose cisplatin (CL), high-dose cisplatin (CH), CL plus mesna (CL+M), and CH plus mesna (CH+M) groups and detected anti-Müllerian hormone (AMH)-positive follicle, oxidative stress status and anti-oxidative capability in ovaries. Results: AMH-positive follicles were significantly decreased after cisplatin administration, which was significantly reversed when mesna was co-administered with cisplatin. The end product of lipid peroxidation, malondialdehyde (MDA), was significantly increased, but the anti-oxidative enzymatic activity of superoxide dismutase (SOD) and glutathione (GSH) were significantly decreased in cisplatin groups when compared with NS group. In contrast, after co-administration of cisplatin with mesna, MDA was significantly decreased whereas the activity of SOD and the concentration of GSH were increased. Moreover, mesna did not decrease the anti-tumor property of cisplatin in HePG2 cell lines. Conclusion: Cisplatin damages the granulosa cells by oxidative stress to deplete the ovarian reserve and mesna could protect ovarian reserve through anti-oxidation. These results might highlight the mechanism of the protection of mesna for ovarian reserve and open an avenue for the application of mesna as a protective additive in cisplatin chemotherapy in clinical practise.

Organic-rich source rock characterization and evaluation of the Cretaceous Qingshankou Formation: results from geophysical logs of the second scientific drilling borehole in the Songliao Basin, NE China

Xiaohuan Zhang,Changchun Zou,Jinhuan Zhao,Ning Li,Shuxia Zhang,Kouamelan Serge Kouamelan,Liang Xiao,Huolin Ma,Yixiong Niu 한국지질과학협의회 2019 Geosciences Journal Vol.23 No.1

The second continental scientific drilling (SKII east) borehole in the Songliao Basin has been planned to be the deepest borehole to drill through the Cretaceous continental strata under the framework of the International Continental Scientific Drilling Program (ICDP) up to date. This borehole was designed not only to explore the potential relationships between dinosaur extinction and climate environment during the Cretaceous but also to achieve new breakthroughs in oil and gas exploration. The high hydrocarbon (oil and gas) potential of a source rock is highly dependent on its organic content. We used geophysical log data of Borehole SKII east to evaluate the organic content of organic-rich source rock. In the period of the first member in the Qingshankou Formation (K2qn1) from the study area, high accommodation space and anoxic environment could promote organic matter deposition. Firstly, based on geological information and abundant geophysical log data, the basic geophysical characteristics (including petrophysical, lithological, mineralogical, and sedimentary properties) of the Qingshankou Formation in Borehole SKII east were studied. Secondly, geophysical log response characteristics (including resistivity, porosity, radioactivity, mineral and element) of organic-rich source rocks were analyzed. Thirdly, we tried to obtain suitable methods to predict total organic carbon (TOC) content of the target formation with geophysical log data. The laboratorymeasured TOC values of core samples from Borehole SKI south were used to make calibrations with calculated TOC values from geophysical logs. Results from improved ΔlogR technique and Dual_Vsh method are consistent, and indicate that these two methods are effective in this formation. The calculated TOC values from these two methods are relatively desirable, and show that the organic-rich source rocks with high TOC content occurred in the K2qn1 (1646.00~1669.00 m). The highest TOC content can reach 9.15%. The bed thicknesses of organic-rich source rocks are totally up to 7.88 m. These organic-rich source rocks can be considered as excellent. This study demonstrated that improve ΔlogR technique can be applied to evaluate source rocks in the formations without maturity data, and the new method Dual_Vsh is also valid in the Qingshankou Formation. The organic-rich source rock evaluation results could promote further exploration and development of oil and gas resources in the upper Cretaceous formations, Songliao Basin.

The association between obesity and glaucoma in older adults: evidence from the China Health and Retirement Longitudinal Study

Zhao Xiaohuan,Bo Qiyu,Sun Junran,Chen Jieqiong,Li Tong,Huang Xiaoxu,Zhou Minwen,Wang Jing,Liu Wenjia,Sun Xiaodong 한국역학회 2023 Epidemiology and Health Vol.45 No.-

Objectives: This study evaluated the association between obesity and glaucoma in middle-aged and older people. A population-based retrospective cohort study was conducted using data from the China Health and Retirement Longitudinal Study.Methods: Glaucoma was assessed via self-reports. Multivariate logistic regression analysis and a Cox proportional hazards model were used to assess the relationship between obesity and glaucoma risk.Results: Older men living in urban areas who were single, smokers, and non-drinkers were found to have a significantly higher incidence of glaucoma (all P<0.05). Diabetes, hypertension, and kidney disease were also associated with higher glaucoma risk, while dyslipidemia was associated with lower risk (all P<0.05). After the model was adjusted for demographic, socio-economic, and health-related variables, obesity was significantly associated with a 10.2% decrease in glaucoma risk according to the Cox proportional hazards model (hazard ratio, 0.898; 95% CI, 0.829-0.973) and an 11.8% risk reduction in the multivariate logistic regression analysis (odds ratio, 0.882; 95% CI, 0.803-0.968). A further subgroup analysis showed that obesity was associated with a reduced risk of glaucoma in people living in rural areas, in smokers, and in those with kidney disease (all P<0.05). Obesity also reduced glaucoma risk in people with diabetes, hypertension, or dyslipidemia more than in healthy controls (all P<0.05).Conclusions: This cohort study suggests that obesity was associated with a reduced risk of glaucoma, especially in rural residents, smokers, and people with kidney disease. Obesity exerted a stronger protective effect in people with diabetes, hypertension, or dyslipidemia than in healthy people.

Structure and Electrical Performance of Na₂C₆O₆ under High Pressure

Wang, Xuan,Zhang, Peijie,Tang, Xingyu,Guan, Junjie,Lin, Xiaohuan,Wang, Yajie,Dong, Xiao,Yue, Binbin,Yan, Jinyuan,Li, Kuo,Zheng, Haiyan,Mao, Ho-kwang American Chemical Society 2019 The Journal of Physical Chemistry Part C Vol. No.

<P>Sodium rhodizonate (Na<SUB>2</SUB>C<SUB>6</SUB>O<SUB>6</SUB>) has very high theoretical capacity as a positive electrode material of sodium-ion batteries, but it still has problems such as low actual capacity and poor electronic/ionic conductivity. In order to improve its conductivity, we investigated its structure and electrical properties under high pressure. By performing in situ X-ray diffraction, Raman, infrared absorption, and alternating current impedance spectroscopy in the range of 0-30 GPa at room temperature, we observed a phase transition at ∼11 GPa, with the conductivity increasing by an order of magnitude. Above ∼20 GPa, Na<SUB>2</SUB>C<SUB>6</SUB>O<SUB>6</SUB> gradually amorphized. During the decompression process, the pressure regulation of the structure and properties of the material are reversible. Our study shows that applying external pressure is an effective tool to improve the conductivity of molecular battery materials. The investigation will help to obtain next-generation electrode materials.</P> [FIG OMISSION]</BR>