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Dissecting neural connectivity patterns within local brain regions is an essential step to understanding the function of the brain.

In Ad-hoc wireless network, connectivity is a fundamental issue which restricts the design of system protocol. Based on the theory of stochastic geometry, a connectivity model focused on signal-to-interference (SIR) ratio is set up in presence of Nakagami-m fading and interference. This paper derives a close formula of connectivity probability with interference and Nakagami-m fading which is never obtained in previous works. Two-dimension shot-noise theory in stochastic geometry for interference is well applied. The formula is verified by simulation. The results show that the connectivity is affected by the scatter of users, wireless propagation environment, interference and so on.

Flying capacitor multilevel inverters are increasingly used in industry applications. In order to improve the harmonic performance of the output voltage under low modulation index region, the paper presents a novel PWM method for flying capacitor multilevel inverters based on the idea of controlling freedom degree. The novel PWM method can balance the flying capacitor voltage in a certain period. The validity of the novel PWM method is demonstratedby the experimental results.

Bcl-2 is best known for its anti-apoptotic function in a wide variety of cell types. The objective of this study was to investigate the effects of bcl-2 on the types of cell demise in the HeLa/bcl-2 cells induced by H2O2. The HeLa cell expressed stably bcl-2 was established and defined as the HeLa/bcl-2 cell strain, while the cell transfected with the empty expression vector was defined as the HeLa/vector cell strain. MTT assay revealed that the HeLa/bcl-2 cells showed a shorter life span. BrdU incorporation assay indicated that the bcl-2 exerted anti-demise effect on the HeLa/bcl-2 cells at the low concentration of H2O2. However, at the high concentration of H2O2, the death of the HeLa/bcl-2 cells was more than that of the HeLa/vector cells. The flow cytometry demonstrated that H2O2 mainly induced apoptosis in the HeLa/vector cells and elicited necrosis in the HeLa/bcl-2 cells. The addition of celecoxib to the cells treated by H2O2 could increase apoptosis in the HeLa/vector cells and convert necrosis into apoptosis in the HeLa/bcl-2 cells. The higher levels of cellular free radical and GSH were found in the HeLa/bcl-2 cells, but not in the HeLa/vector cells. With 200 microM H2O2 challenge for 48 h, the level of the cellular free radical was increased in the both strains, while the level of the GSH was decreased in the both strains. Celecoxib could reverse the difference between the both strains led by H2O2. Western blotting showed that the expression of COX-2 was always higher in the HeLa/bcl-2 cells than in the HeLa/vector cells under the both of treated and untreated with H2O2, while the level of COX-1 was relative stable in the both strains. These results suggested that the crosstalk between the bcl-2 and the COX-2 pathways could exist, the bcl-2 might up-regulate COX-2 to modify sensitivity to the types of demise in the HeLa/bcl-2 cell.