Numerical modelling of vibration response in loess hills due to a high-speed train on railway viaduct

In order to accurately analyze vibration characteristics and site effects of loess hills under moving load of a highspeed train,four types of loess hill models under railway viaduct was established by ABAQUS of finite element analysis software by field test.The dynamic response and stability of loess hills under two different vibration sources under high-speed train load were studied by using two-dimensional equivalent linear response timehistory analysis,and the influence of the mechanical parameters of loess on the vibration of different types of loess hill was analyzed.Results show that there are obvious differences between peak displacement cloud maps of loess hills under the railway viaduct under gravity and train load action.We analyzed the influence of the change of elastic modulus on vibration propagation of soil of foundation and loess knoll,and found that the change of elastic modulus of soil in different position of foundation has more effect on vibration propagation than that of loess knoll soil.At the same time,the vertical acceleration cloud maps of the four types of loess hills are obviously different.

Highly sensitive H_(2)O_(2)-scavenging nano-bionic system for precise treatment of atherosclerosis

In atherosclerosis,chronic inflammatory processes in local diseased areas may lead to the accumulation of reactive oxygen species(ROS).In this study,we devised a highly sensitive H_(2)O_(2)-scavenging nanobionic system loaded with probucol(RPP-PU),to treat atherosclerosis more effectively.The RPP material had high sensitivity to H_(2)O_(2),and the response sensitivity could be reduced from 40 to 10μmol/L which was close to the lowest concentration of H_(2)O_(2)levels of the pathological environment.RPP-PU delayed the release and prolonged the duration of PU in vivo.In Apolipoprotein E deficient(ApoE-/-)mice,RPP-PU effectively eliminated pathological ROS,reduced the level of lipids and related metabolic enzymes,and significantly decreased the area of vascular plaques and fibers.Our study demonstrated that the H_(2)O_(2)-scavenging nanobionic system could scavenge the abundant ROS in the atherosclerosis lesion,thereby reducing the oxidative stress for treating atherosclerosis and thus achieve the therapeutic goals with atherosclerosis more desirably.

A novel lncRNA, Lnc-OC1, promotes ovarian cancer cell proliferation and migration by sponging miR-34a and miR-34c

Long non-coding RNAs（lncRNAs） have been reported to be of great importance in tumorigenesis and progression of a variety of cancers. However, the role of lncRNAs in ovarian cancer（OC） remains largely unknown. In the present study, we identified a novel lncRNA, LOC100288181（named as Lnc-OC1）, which acted as a key regulator in the development and progression of OC. The combined Gene Expression Omnibus（GEO） database analysis revealed that Lnc-OC1 was significantly upregulated in OC tissues and Kaplan-Meier survival analysis confirmed that high Lnc-OC1 expression was associated with poor prognosis of OC patients. Importantly, we also demonstrated that knockdown of Lnc-OC1 suppressed cell proliferation, colony formation, invasion and migration in vitro and inhibited tumorigenicity in vivo.Mechanistically, Lnc-OC1 repressed the expression of endogenous miR-34 a and miR-34 c as a sponge and vice versa. Moreover, rescue experiments demonstrated that the oncogenic function of Lnc-OC1 at least partially depended on suppressing miR-34 a and miR-34 c. In conclusion, our results suggest that the LncOC1-miR-34 a/34 c axis may play a pivotal role in OC, and may serve as a potential diagnostic biomarker and a powerful therapeutic target for OC.

Significant difference between sirolimus and paclitaxel nanoparticles in antiproliferation effect in normoxia and hypoxia: The basis of better selection of atherosclerosis treatment

Compared with paclitaxel,sirolimus has been more used in the treatment of vascular restenosis gradually as an anti-proliferative drug,but few basic studies have elucidated its mechanism.The anti-proliferative effects of sirolimus or paclitaxel have been demonstrated by numerous studies under normoxia,but few studies have been achieved focusing hypoxia.In this study,porcine carotid artery injury model and classical cobalt chloride hypoxia cell model were established.Sirolimus nanoparticles(SRM-NPs),paclitaxel nanoparticles(PTX-NPs)and blank nanoparticles(Blank-NPs)were prepared respectively.The effect of RPM-NPs on the degree of stenosis,proliferative index and the expression of PCNA after 28 days of porcine carotid artery injury model was evaluated.Compared with saline group and SRM groups,SRM-NPs group suppressed vascular stenosis,proliferative index and the expression of PCNA(P<0.01 and P<0.05).Endothelial cell(EC)and smooth muscle cell(SMC)were pre-treated with cobaltous chloride,followed by SRM-NPs,PTX-NPs,Blank-NPs or PBS control treating,the effects on cell proliferation,HIF-1 expression and glycolysis were detected.SRM-NPs could inhibit EC and SMC proliferation under hypoxia,while PTX-NPs couldn't(P<0.001).Significant differences between sirolimus and paclitaxel NPs in anti-proliferation effect under normoxia and hypoxia may due to the different inhibitory effects on HIF-1αexpression and glycolysis.In conclusion,these results suggest that sirolimus can inhibit the proliferation of hypoxic cells more effectively than paclitaxel.These observations may provide a basis for understanding clinical vascular stenosis therapeutic differences between rapamycin and paclitaxel.

A Simple and Novel Electrochemical Sensor Based on Phosphomolybdic-Polypyrrole Film Modified Electrode for Highly Sensitive Detection of Cholic Acid

A simpe electrochemical sensor for detection of cholic acid （CA） was designed by modifying phosphomolybdate （PMol2） doped polypyrrole （PPy） film on glassy carbon electrode （PMo12-PPy/GCE）. The electrochemical behavior of CA on PMo12-PPy/GCE was investigated by cyclic voltammetry and 0.5 order differential voltammetry. The results indicated that CA had high inhibitory activity toward the peak currents of PMo12-PPy/GCE. The reduction peak currents were linearly related to the logarithmic value of the concentration of CA from 1.0 × 10^- 7 to 1.0 × 10^-3 mol/L with a low detection limit of 1.0 × 10^- 8 mol/L. The developed sensor exhibited excellent sensitivity, selectivity and stability for detection of CA, and it could be successfully applied to detect the level of CA in the urine samples. Moreover, the response mechanism of CA on the PMo12-PPy/GCE was discussed in detail.

Stability analysis for delayed viral infection model with multitarget cells and general incidence rate

In this paper, the sharp threshold properties of a （2n ＋ 1）-dimensional delayed viral infection model are investigated. This model combines with n classes of uninfected tar- get cells, n classes of infected cells and nonlinear incidence rate h（x,v）. Two kinds of distributed time delays are incorporated into the model to describe the time needed for infection of uninfected target cells and virus replication. Under certain conditions, it is shown that the basic reproduction number is a threshold parameter for the existence of the equilibria, uniform persistence, as well as for global stability of the equilibria of the model.