Study on the Relationship between Electron Transfer and Electrical Properties of XLPE/Modification SR under Polarity Reversal.

The insulation of high-voltage direct-current (HVDC) cables experiences a short period of voltage polarity reversal when the power flow is adjusted, leading to sever field distortion in this situation. Consequently, improving the insulation performance of the composite insulation structure in these cables has become an urgent challenge. In this paper, SiC-SR (silicone rubber) and TiO2-SR nanocomposites were chosen for fabricating HVDC cable accessories. These nanocomposites were prepared using the solution blending method, and an electro-acoustic pulse (PEA) space charge test platform was established to explore the electron transfer mechanism. The space charge characteristics and field strength distribution of a double-layer dielectric composed of cross-linked polyethylene (XLPE) and nano-composite SR at different concentrations were studied during voltage polarity reversal. Additionally, a self-built breakdown platform for flake samples was established to explore the effect of the nanoparticle doping concentration on the breakdown field strength of double-layer composite media under polarity reversal. Therefore, a correlation was established between the micro electron transfer process and the macro electrical properties of polymers (XLPE/SR). The results show that optimal concentrations of nano-SiC and TiO2 particles introduce deep traps in the SR matrix, significantly inhibiting charge accumulation and electric field distortion at the interface, thereby effectively improving the dielectric strength of the double-layer polymers (XLPE/SR).

Effects of batroxobin treatment on the survival of random skin flaps in rats.

OBJECTIVE: Batroxobin is a medicinal preparation extracted from the venom of the Fer-de-Lance snake, and is used to lower blood viscosity, promote blood fibrinogen decomposition, and inhibit thrombosis. This research is to investigate whether batroxobin can improve the survival of random skin flaps in a rat model. MATERIALS AND METHODS: Dorsal McFarlane flaps were harvested from 36 rats divided into two groups. Experimental group: Batroxobin was administered via the tail vein once daily. CONTROL GROUP: The same amount of normal saline was injected instead. On day 2, superoxide dismutase (SOD) and malondialdehyde (MDA) levels were measured. On day 7, tissue slices were stained with haematoxylin and eosin. Expression of vascular endothelial growth factor (VEGF) was immunohistochemically evaluated. Microcirculatory flow was measured by laser Doppler flowmetry. Flap angiography, using the lead oxide-gelatin injection technique, was performed with the aid of a soft X-ray machine. RESULTS: The batroxobin group exhibited a greater mean flap survival area, a better microcirculatory flow, and higher-level expression of SOD and VEGF compared with the control group. However, the MDA level was significantly reduced. CONCLUSION: Batroxobin effectively improved the survival of random skin flaps.

Effect of oxytocin on the survival of random skin flaps.

Random flap transplantation is widely used to repair and rebuild skin soft tissue. However, such flaps exhibit poor survival. Plastic surgeons seek to improve flap survival. We explored whether oxytocin improved skin flap survival. Overlength random skin flaps (9 × 3 cm) were established on backs of 80 healthy male SD rats randomly divided into two groups. One group was injected daily with oxytocin (1 mg/kg; test group) and the other with normal saline (control group). On postoperative day 2, malondialdehyde (MDA) and superoxide dismutase (SOD) levels were measured. On postoperative day 7, the flap survival area was measured using transparent graph paper. Microvessel numbers were evaluated histologically by hematoxylin and eosin staining. VEGF expression was assessed immunohistochemically. Angiogenesis was evaluated via lead oxide-gelatin angiography and blood flow via laser Doppler flowmetry. In the test group compared with the control group, the flap survival rate and SOD activity were increased markedly, the MDA level was decreased, and according to hematoxylin and eosin staining, inflammation was significantly attenuated. In addition, the test group exhibited higher levels of VEGF and skin flap angiogenesis. Oxytocin improved flap survival rate by increasing microcirculation and angiogenesis and attenuating ischemia-reperfusion injury.

[Preliminary study of history of senna be used in China--On phenomenon about "reign medicine localized"].

Senna is one of the commonly used traditional Chinese medicine at present. After the preliminary research that the drug medication history in China is not long, in our country ancient times, only "Hui prescription" in the records, other all kinds of traditional Chinese medicine literature rarely mentioned. Since modern times, the Chinese medicine in the medicine in the literature of the time and the modern western medicine books in the Chinese version of the time generally close, may be related to the introduction of Western medicine. At the end of Qing Dynasty and the early Republic of China, Chinese literature about the drug property theory of herbal medicine is seldom discussed, and had been seen as "western medicine" (foreign medicine), with the medication experience continue to accumulate, widespread popularity and other factors, the drug gradually Chinese scholars have constructed a relatively complete theory of the resistance, so as to realize the "localization".