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Ice breaking has become one of the main problems faced by ships and other equipment operating in an ice-covered water region. New methods are always being pursued and studied to improve ice-breaking capabilities and efficiencies. Based on the strong damage capability, a high-speed water jet impact is proposed to be used to break an ice plate in contact with water. A series of experiments of water jet impacting ice were performed in a transparent water tank, where the water jets at tens of metres per second were generated by a home-made device and circular ice plates of various thicknesses and scales were produced in a cold room. The entire evolution of the water jet and ice was recorded by two high-speed cameras from the top and front views simultaneously. The focus was the responses of the ice plate, such as crack development and breakup, under the high-speed water jet loads, which involved compressible pressure ${P_1}$ and incompressible pressure ${P_2}$ . According to the main cause and crack development sequence, it was found that the damage of the ice could be roughly divided into five patterns. On this basis, the effects of water jet strength, ice thickness, ice plate size and boundary conditions were also investigated. Experiments validated the ice-breaking capability of the high-speed water jet, which could be a new auxiliary ice-breaking method in the future.

Oxidative stress and inflammation are the most common causes of myocardial ischemia and hypoxia. This article focuses on the effect of p66ShcA on H2O2-induced cardiomyocytes.The p66ShcA knockdown model of H9c2 cells was constructed by plasmid transfection. After treatment of different groups with H2O2, oxidative stress-related factors and inflammatory factors were detected.The expressions of SOD1, SOD2, GPX1, and GPX3 in H2O2 cells were significantly decreased, IL-1β and IL-6 expression were significantly increased, while p66ShcA siRNA negative group could promote the expression of SOD1, SOD2, GPX1, and GPX3, inhibit the expression of IL-1β and IL-6 significantly, and activates the Keap1/Nrf2 pathways.Knockdown of p66ShcA can activate Keap1/Nrf2 pathway, which inhibits H2O2-induced oxidative stress and inflammation in H9c2 cells.

We investigate the effect of long non-coding RNA H19 in acute myocardial infarction (AMI) and the underlying mechanism.C57BL/6 mice were subjected to AMI and injected with lentivirus pcDNA-H19. After AMI procedures for 3 weeks, cardiac function was detected by echocardiography. The infarct size was stained by triphenyltetrazolium chloride. H19 expression in mice was measured by quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR). Protein expressions of LC3, Beclin-1, and ATG-7 in mice were measured by Western blot.Our results indicated that H19 expression was significantly downregulated in the infarcted myocardium. Overexpression of H19 after injection with pcDNA-H19 in mice could reduce infarct size and improve cardiac function through upregulating the ratio of LC3-II/I and expressions of Beclin-1 and ATG-7.Overexpression of H19 could protect AMI in mice via activating autophagy.

To study the application timing and effect of intra-aortic balloon pump (IABP) in the emergency PCI treatment of patients with combined acute myocardial infarction (AMI) and cardiogenic shock (CS).84 cases of patients with combined AMI and CS under PCI in emergency treatment were randomly divided into the control group (n=42) and observational group (n=42). The control group underwent IABP again, after the invalidation of internal medicine drug treatment, while the observational group underwent IABP before the operation. We compared the effects of treatment.After the intervention, the averages of arterial pressure and urine volume were increased in both groups than before (p0.05). The average of heart rate was decreased, and the improvement in the observational group was more significant (p0.05). However, the mortality rate in the observational group during the perioperative period was decreased than the control group as well as, the success rate of off-respirator was significant (p0.05). The comparison of IABP complication occurrence rate as well as the survival rate after 1-year follow-up between both groups was not significantly different. Additionally, whereas the NYHA grouping in two groups was gradually improved, the difference was not statistically significant between both groups. However, in the observational group, the LVEF after one-month follow-up was significantly higher than in the control group (p0.05), but not when comparing 1-year. VEDd at each time point in two groups were also similar.The early IABP can improve hemodynamics of patients with combined AMI and CS under emergency PCI. It can reduce perioperative mortality rate, improve the success rate of off-respirator, but cannot increase IABP complication incidence rate while having little influence on the long-term survival rate and cardiac function indicator.

In this study, we aimed to explore the curative effect and safety of neural stem cell intrathecal transplantation for the treatment of cerebral hemorrhage. We transplanted 4.0 x 10(8) neural stem cells per procedure into the subarachnoid space by lumbar puncture 7 days after cerebral hemorrhage, twice a week, a total of 4 times. NIHSS scores and brain CT scans were conducted to assess neural functions and the volume of perihematoma lesions in patients on days 1, 7, 14, 21, and 28. We found that the NIHSS scores and the volume of the perihematoma lesions were significantly reduced after day 14. The differences before and after treatment were highly significant in intra- and between-group comparisons (P < 0.05). There were no adverse reactions, except for transient fever and shivering in a few patients. Our data suggest that the use of neural stem cells in intrathecal transplantation for the treatment of cerebral hemorrhage is safe and effective.

Since 1992 the solar tower telescope of Nanjing University (118°51′ E, 32°03′ N) as well as its multichannel solar spectrograph, originally established in 1982, have been reconstructed and a two-channel imaging spectrograph has been operated successfully. The apertures of the coelostat and the secondary mirror are both 60 cm. The spherical objective mirror, having an aperture of 43 cm and a focal length of 2170 cm, produces a solar image of 20 cm diameter. Two auxiliary telescopes using a small fraction of the coelostat's aperture were set up for guiding and Hα monochromatic monitoring. A multichannel spectrograph can be operated in six wavebands simultaneously. A CCD imaging spectrograph can be used for data acquisition at Hα and Caii K line wavebands automatically and simultaneously. The instrument consists of two CCD cameras, an image processor (SR-151), a personal computer, and a mechanical scanning device. The principal characteristics of the instruments are described. Some observational results are presented as examples.