Inverse problems for nonlinear progressive waves

We propose and study several inverse problems associated with the nonlinear progressive waves that arise in infrasonic inversions. The nonlinear progressive equation (NPE) is of a quasilinear form $\partial_t^2 u=\Delta f(x, u)$ with $f(x, u)=c_1(x) u+c_2(x) u^n$, $n\geq 2$, and can be derived from the hyperbolic system of conservation laws associated with the Euler equations. We establish unique identifiability results in determining $f(x, u)$ as well as the associated initial data by the boundary measurement. Our analysis relies on high-order linearisation and construction of proper Gaussian beam solutions for the underlying wave equations. In addition to its theoretical interest, we connect our study to applications of practical importance in infrasound waveform inversion

PO-014 The effects of HIIT on ROS-AMPK- PGC-1α pathway in skeletal muscle and VO2max of ageing Wistar rats.

Objective To observe the 16 weeks of HIIT intervention on SOD,ROS and its related factors AMPK and oxidation capacity PGC-1α expression and the influence of the VO2max and its change rule in the process of the natural aging rats, To explore the correlation between the expression of ROS, AMPK and PGC-1αand the change of VO2max; Furthermore, it provides a theoretical basis for HIIT to delay the reduction of aerobic capacity in skeletal muscle ageing. Methods 58 male wistar rats(age：32 weeks) were selected and randomly divided into quiet group (C) and HIIT intervention group (H). All rats were fed in the barrier environment. Each group of rats entered the animal laboratory for a week of adaptive feeding and exercise. VO2max was tested and observed every two weeks in each group. Rats of group C don't exercise, group H at a rate of 50%, 70% and 90% VO2max corresponding alternation of 50 min/day, 5 days/week, for 16 weeks of exercise intervention, and according to the VO2max test results the exercise intensity. Both groups of rats in the intervention of 8 weeks, 16 weeks after the end of the 24 hours of materials, stripping rats soleus, SOD and content of ROS was tested by multifunctional enzyme mark, using western blot test the expression of AMPK and PGC-1α. VO2max, SOD, ROS test results and AMPK, PGC-1α, and relative expression data were analyzed using SPSS for one way ANOVA. Results The cardiopulmonary endurance of rats in group C and group H showed a decreasing trend in group C and group H during HIIT intervention, but the decrease trend in group H was slower than that in group C. 2. During 16 weeks aging , SOD expression of group C in the process of rendering first rise after falling, and expressed in 8 weeks SOD content was significantly lower than base value (P < 0.05), 16 weeks group C SOD levels higher than the base state. After 16 weeks of intervention, the expression of SOD in group H was relatively flat in the first 8 weeks, and the trend was in 8-16 weeks, and was significantly lower than 8 weeks in 16 weeks (P < 0.05). 3.The ROS content was significantly higher than basic state in 8 weeks and 16 weeks in the intervention process (P<0.05), and the ROS content was significantly higher than 8 weeks (P<0.05) at 16 weeks. The ROS content of group C and group H was significantly higher than that in the group at 8 weeks (P < 0.05). 4.The AMPK content in group C was significantly lower than that of the basic value (P<0.05), and the AMPK content in group H was significantly higher than that in group C (P<0.05). 5.After the intervention of 16 weeks, the content of PGC-1α in group C and group H showed a decrease trend and significantly lower than the basic value (P<0.05), but the content of group H was significantly higher than that of group C (P<0.05). 6.The changes of AMPK, PGC-1α and cardiopulmonary endurance were the same in all groups during the intervention. Conclusions 1.16 weeks of HIIT can effectively delay the decrease of SOD content in the aging rats, thus inhibiting the accumulation of ROS in the body. 2.16 weeks of HIIT intervention can effectively delay the expression of VO2max and AMPK and PGC-1α in aging rats. 3.16 weeks HIIT may delay the decrease of AMPK-PGC1 protein expression by inhibiting the accumulation of skeletal muscle ROS in the aging rats, thus inhibiting the decrease of VO2max

Meta-analysis: The efficacy of metformin and other anti-hyperglycemic agents in prolonging the survival of hepatocellular carcinoma patients with type 2 diabetes

Introduction: This study aimed to compare the therapeutic efficacy of metformin and other anti-hyperglycemic agents in hepatocellular carcinoma (HCC) patients with type 2 diabetes (T2D). Materials: A systematic electronic search on keywords including HCC and different anti-hyperglycemic agents was performed through electronic databases including Medline and EMBASE. The primary outcome was the overall survival (OS). The secondary outcomes were the recurrence-free survival (RFS) and progression-free survival (PFS). Results: Six retrospective cohort studies were included for analysis: Four studies with curative treatment for HCC (618 patients with metformin and 532 patients with other anti-hyperglycemic agents) and two studies with non-curative treatment for HCC (92 patients with metformin and 57 patients with other anti-hyperglycemic agents). Treatment with metformin was associated with significantly longer OS (OR1 yr = 2.62, 95%CI: 1.76–3.90; OR3 yr = 3.14, 95%CI: 2.33–4.24; OR5 yr = 3.31, 95%CI: 2.39–4.59, all P  50%). Conclusions: Metformin significantly prolonged the survival of HCC patients with T2D after the curative treatment of HCC. However, the efficacy of metformin needs to be further determined after non-curative therapies for HCC patients with T2D