High-strength bolt corrosion fatigue life model and application.

The corrosion fatigue performance of high-strength bolt was studied. Based on the fracture mechanics theory and the Gerberich-Chen formula, the high-strength bolt corrosion fracture crack model and the fatigue life model were established. The high-strength bolt crack depth and the fatigue life under corrosion environment were quantitatively analyzed. The factors affecting high-strength bolt corrosion fatigue life were discussed. The result showed that the high-strength bolt corrosion fracture biggest crack depth reduces along with the material yield strength and the applied stress increases. The material yield strength was the major factor. And the high-strength bolt corrosion fatigue life reduced along with the increase of material strength, the applied stress or stress amplitude. The stress amplitude influenced the most, and the material yield strength influenced the least. Low bolt strength and a low stress amplitude level could extend high-strength bolt corrosion fatigue life.

Geometric nonlinear analysis of self-anchored cable-stayed suspension bridges.

Geometric nonlinearity of self-anchored cable-stayed suspension bridges is studied in this paper. The repercussion of shrinkage and creep of concrete, rise-to-span ratio, and girder camber on the system is discussed. A self-anchored cable-stayed suspension bridge with a main span of 800 m is analyzed with linear theory, second-order theory, and nonlinear theory, respectively. In the condition of various rise-to-span ratios and girder cambers, the moments and displacements of both the girder and the pylon under live load are acquired. Based on the results it is derived that the second-order theory can be adopted to analyze a self-anchored cable-stayed suspension bridge with a main span of 800 m, and the error is less than 6%. The shrinkage and creep of concrete impose a conspicuous impact on the structure. And it outmatches suspension bridges for system stiffness. As the rise-to-span ratio increases, the axial forces of the main cable and the girder decline. The system stiffness rises with the girder camber being employed.

In Situ Labeling of Erythrocyte Membrane Anion Channel Proteins with Gold Nanoparticles Observed by Cryo-Scanning Electron Microscopy / 分析化学

Band 3 protein is an important channel protein in the erythrocyte membrane which mediates the anion transport process inside and outside the cell membrane,as well as contributes to the maintenance of erythrocyte morphology,and has important physiological functions.However,the distribution state of this protein in the primary cell membrane is not known.Cryo-scanning electron microscopy enables imaging of the surface morphology of biological samples in a near-physiological state.In order to investigate the distribution of band 3 protein on erythrocyte membranes under physiological conditions,the present study utilized 5-nm gold nanoparticles modified with the antibodies to specifically bind to the band 3 protein on human blood erythrocyte membranes and imaged them by cryo-scanning electron microscopy,to obtain distribution of band 3 protein on human blood erythrocyte membranes.The results showed that the membrane proteins on the erythrocyte membranes tended to be clustered and distributed to form ″protein islands″,and band 3 proteins were mainly distributed in these protein islands,which were tightly connected with each other to form several functional microregions to play their respective roles.

Research progress on regulation of N6-adenylate methylation modification in lipid metabolism disorders / 生理学报

Lipid metabolism is a complex physiological process, which is closely related to nutrient regulation, hormone balance and endocrine function. It involves the interactions of multiple factors and signal transduction pathways. Lipid metabolism disorder is one of the main mechanisms to induce a variety of diseases, such as obesity, diabetes, non-alcoholic fatty liver disease, hepatitis, hepatocellular carcinoma and their complications. At present, more and more studies have found that the "dynamic modification" of N6-adenylate methylation (m6A) on RNA represents a new "post-transcriptional" regulation mode. m6A methylation modification can occur in mRNA, tRNA, ncRNA, etc. Its abnormal modification can regulate gene expression changes and alternative splicing events. Many latest references have reported that m6A RNA modification is involved in the epigenetic regulation of lipid metabolism disorder. Based on the major diseases induced by lipid metabolism disorders, we reviewed the regulatory roles of m6A modification in the occurrence and development of those diseases. These overall findings inform further in-depth investigations of the underlying molecular mechanisms regarding the pathogenesis of lipid metabolism disorders from the perspective of epigenetics, and provide reference for health prevention, molecular diagnosis and treatment of related diseases.

Treatment of Intractable Pediatric Mycoplasma Pneumonia by Qingfei Huoxue Recipe Combined Azithromycin: a Random Parallel Control Study / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To explore the effect of Qingfei Huoxue Recipe (QHR) combined azithromycin in treatment of intractable pediatric mycoplasma pneumonia.</p><p><b>METHODS</b>Totally 124 intractable pediatric mycoplasma pneumonia patients at our hospital were recruited in this study, and randomly assigned to the treatment group and the control group, 62 in each group. Patients in the control group took azithromycin, while those in the treatment group additionally took QHR. All patients received omnibearing systematic nursing. Therapeutic efficacy, clinical indices (such as disappearance time of cough and rales, recovery time of body temperature) , and the incidence of adverse reactions were observed.</p><p><b>RESULTS</b>After treatment the total effective rate was 91.94% (57/62 cases) in the treatment group and 77. 42% (48/62 cases) in the control group with statistical difference (P < 0.05). Compared with the control group, disappearance time of cough and rales, recovery time of body temperature were obviously shortened in the treatment group with statistical difference (P < 0.01). There was statistical difference in the incidence of adverse reactions between the two groups [3.23% (2/62 cases) vs 38.71% (24/62 cases) , P < 0.01].</p><p><b>CONCLUSION</b>In clinical treatment for intractable pediatric mycoplasma pneumonia, Chinese medicine combined Western medicine plus scientific and systematic nursing showed more obvious advantages with significant efficacy, which was worth spreading.</p>

Effect of UCP2-siRNA on inflammatory response of cardiomyocytes induced by septic serum / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To study the effect of uncoupling protein 2 (UCP2)-siRNA on the inflammatory response of rat cardiomyocytes (H9C2) induced by septic serum and to investigate the possible role of UCP2 in the development of septic cardiomyopathy.</p><p><b>METHODS</b>Serum samples were separately collected from normal rats and septic rats. Cultured rat cardiac cells (H9C2) were randomly divided into blank control, normal serum, 10% septic serum, UCP2-siRNA+10% septic serum and negative siRNA+10% septic serum groups. Stimulation with 10% septic serum was performed for 12 hours in relevant groups. The mRNA expression of tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1β) was measured by RT-PCR. The expression of phosphorylated p38 mitogen-activated protein kinase (p-p38 MAPK) and nuclear factor-kappa B (NF-κB) was measured by Western blot.</p><p><b>RESULTS</b>The expression levels of p-p38 and NF-κB in the UCP2-siRNA+10% septic serum group were significantly higher than in the 10% septic serum group (P<0.05). The UCP2-siRNA+10% septic serum group had a significantly higher TNF-α mRNA expression than the 10% septic serum group (P<0.01), but IL-1β mRNA expression showed no significant difference between the two groups.</p><p><b>CONCLUSIONS</b>UCP2 plays a regulatory role in the activation of p38 MAPK and NF-κB and the expression of downstream inflammatory mediators in H9C2 cells stimulated with septic serum.</p>