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Objective To investigate the relationship between the CT parameters of degree of brain tissue displacement and intracranial pressure (ICP) in patients with closed traumatic brain injury (TBI). Methods A total of 84 patients with closed TBI were chosen from January 2018 to March 2021 in The People's Hospital of Kaizhou District. Head CT examination was performed and CT values on both sides of the midline, the ratio of CT values on both sides of the midline and the midline shift distance were measured. Pearson and partial correlation analyses were used to investigate the correlation between head CT parameters and ICP in patients with closed TBI. Receiver operating characteristic (ROC) curve was used to evaluate the predictive efficacy of CT parameters in increased ICP. Results Correlation analysis showed that the ratio of CT values on both sides of the midline (r = 0.478, P = 0.000) and midline shift distance (r = 0.378, P = 0.000) were positively correlated with ICP. ROC curve showed that the ratio of CT values on both sides of the midline, the midline shift distance and the combined index prediction of ICP were 0.79 (95%CI: 0.687-0.889, P = 0.000), 0.89 (95%CI: 0.794-0.943, P = 0.000) and 0.91 (95%CI: 0.845-0.970, P = 0.000), the sensitivity and specificity were 80.95% and 73.81%, 69.05% and 90.48%, 80.95% and 85.71%, and the prediction efficiency of the combined index was better than the ratio of CT values on both sides of the midline (t = - 2.964, P = 0.003). Conclusions The CT parameters of brain tissue displacement degree in patients with unilateral closed TBI are closely related to the ICP, and the combination of the ratio of CT values on both sides of the midline and midline shift distance can predict ICP increase more effectively.

We propose an efficient bit-loading algorithm to minimize the total power to transmit a target rate of a single user in OFDM communication systems. Considering the digital modulations exploited by 802. 11a, which are BPSK, QPSK, 16QAM and 64QAM (constellation using Gray code and each sub-carrier carrying a maximum of 6 bits) , ⌊ RT/6 ⌋ subcarriers which have litter power addition are allocated with 2 bits each time. The proposed bit loading algorithm is optimal and has the same performance as Hughes-Hartogs algorithm, but greatly reduces the computational complexity. Simulation results show that the proposed bit loading algorithm has the same bit allocation results as Hughes-Hartogs algorithm, but the computational complexity is less than 50% compared with that of Hughes-Hartogs algorithm. The computational complexity will be further reduced when the transmission rate or subcarriers number increases. [ABSTRACT FROM AUTHOR]

The accumulation carriers and the trapped carriers are found in many organic light-emitting diodes (OLEDs) more or less, which can lead to a great loss of carriers and weaken the performance of devices. We have investigated a host-guest-system containing the green phosphorescent emitter tris[2-phenylpyridinato-C2,N]iridium(Ⅲ) [Ir(ppy)3] and one host material with transient electroluminescence (EL). The charge recombination, accumulation and light emission mechanisms of the phosphorescent organic light-emitting diodes (PhOLEDs) with different host materials were analyzed. The structure was fabricated as ITO/NPB(30 nm)/host: Ir(ppy)3/BCP(10 nm)/Alq3(20 nm)/LiF(0.7 nm)/Al(100 nm),the hosts were CBP, PVK and TAZ respectively. These results showed the transient EL was strongly dependent on host materials. Compared to devices of host material CBP and PVK, only those with the host material TAZ as the emitting layer exhibited strong electroluminescence overshoots between 1 and 3 μs after turning off the voltage pulse at room temperatures. To further elucidate the generality of the overshoots, we monitored their dependence on the dopant concentration. The transient EL results in host-guest-system devices demonstrated a direct link between the strong overshoot effect and charge trapping in the emitting guest molecules. The excessive electrons in the guest sites could be a major factor inducing significant strong overshoot phenomenon in the TAZ: Ir(ppy)3 layer. We attributed these overshoot effect to the electrons accumulated on Ir(ppy)3 sites and accumulated holes in the vicinity of the HBL/EML interface. As a result, we obtained a better understanding of carriers’ dynamics and recombination process of PhOLEDs after turning off the voltage pules. The new understanding of the charge carriers and exciton dynamics of PhOLEDs is instrumental in directing the efforts of developing stable and high-efficiency PhOLEDs.

Objective: To investigate the roles of phosphatidylinositol 3 kinase regulatory subunit alpha (PIK3R1）gene in the development of hepatocellular carcinoma （HCC）., Methods: Surgical specimens of liver cancer and corresponding pericancerous liver tissue were collected from 20 patients with hepatocellular carcinoma. Expression of p85α, encoded by PIK3R1, in HCC tissue specimens was detected by Western blotting and immunohistochemistry. HCC HepG2 cells were transfected with PIK3R1 siRNA or PIK3R1-cDNA. The expression of PIK3R1 in transfected HepG2 cells or control cells were detected by real-time PCR. Cell proliferation was evaluated by MTT, colony formation assays and flow cytometry respectively. The expression of PI3K/AKT pathway-related proteins were detected by Western blotting., Results: The expression of p85α in liver tissue was higher than that in pericancerous tissues (1.27±0.58 vs 0.99±0.47，t=-3.25，P<0.05）. The expression of PIK3R1 was decreased by 0.19±0.03 fold in PIK3R1siRNA-transfected HepG2 cells(t=46.77，P<0.05)，and increased by 32.36±3.33 fold in PIK3R1 cDNA -transfected cells（t=-16.31， P<0.05）. MTT result showed that PIK3R1 siRNA inhibited growth of HepG2 cells （0.611±0.072 vs 0.807±0.059，t=3.65，P<0.05），while PIK3R1 cDNA increased the cell growth（0.937±0.060 vs 0.693±0.065，t=-4.78，P<0.05）. PIK3R1 siRNA transfected cells presented lower colony-forming efficiency than control group（3.8%±0.84% vs 15.0%±2.3%，t=7.92，P<0.05），while PIK3R1 cDNA transfected cells had higher colony-forming efficiency than control group (23.6%±3.4% vs 12.0%±1.5%，t=-5.40，P<0.05）. PIK3R1 siRNA reduced the ratio of S phase cells（13.9%±0.015% vs 32.9%±0.07%，t=45.97，P<0.01, while PIK3R1 cDNA increased S phase cells（56.33%±0.024% vs 31.94%±0.042%，t=-8.73，P<0.01）. PIK3R1 increased the level of p-AKT and decreased p53 level. CONCLUSION：p85α is highly expressed in HCC，and PIK3R1 gene may promote proliferation of HepG2 cells by activating PI3K/AKT pathway.

Aim: To explore whether antisense blocking of protein kinase C alpha (PKCalpha) would reverse multi-drug resistance (MDR) in the vincristine (VCR)-resistant human gastric cancer cell line SGC7901/VCR., Methods: SGC7901/VCR cells expressing antisense PKCalpha, SGC7901/VCR/aPKC, were established by transfection with a recombinant plasmid reversely inserted with PKCalpha cDNA. Empty vector (PCI-neo)-transfected cell clones, SGC7901/VCR/neo, served as the control. Western blot method was used to detect PKCalpha content in SGC7901, SGC7901/VCR, SGC7901/VCR/neo and SGC7901/VCR/aPKC cells, using PKCalpha-specific antibody. The sensitivity of SGC7901, SGC7901/VCR, SGC7901/VCR/neo and SGC7901/VCR/aPKC cells to doxorubicin (DOX) in vitro was determined by MTT assay. The uptake of DOX in these cells was detected with fluorescence spectrophotometer., Results: Western blot analysis showed that the PKCalpha protein level was about 8.7-fold higher in SGC7901/VCR cells than that in SGC7901 cells, whereas the protein expression of PKCalpha was reduced by 78% in SGC7901/VCR/aPKC cells when compared with the SGC7901/VCR cells. SGC7901/VCR/aPKC cells had a 4.2-fold increase in DOX cytotoxicity, accompanied by a 1.7-fold increase of DOX accumulation in comparison with SGC7901/VCR cells., Conclusion: PKCalpha positively regulates MDR in SGC7901 cells, and inhibition of PKCalpha can partially attenuate MDR in human gastric cancer cells.