Angle-of-attack and angle-of-sideslip estimation and complementary filter design for civil aircraft.

Angle-of-Attack (AOA) and angle-of-sideslip (AOS) are critical flight parameters affecting the flight safety, and their accuracy and reliability directly impact the operating status and performance of some significant airborne systems. To enhance the redundancy and accuracy of AOA and AOS, this article investigates the problem of the airflow angles estimation and complementary filter design for civil aircraft. Specifically, an extended Kalman filter based AOA and AOS estimation method considering acceleration correction is developed to increase the redundancy. Subsequently, a novel inertial AOA and inertial AOS calculation method using attitude angles, azimuth angle, and flight path angle is introduced, and two schemes for designing the discrete complementary filter based on Tustin transform are presented to improve the accuracy. Through simulations, the developed algorithms are verified, and the results illustrate that the AOA estimation error is within ± 0.6°, and the AOS estimation error is within ± 0.3°.

MicroRNA-135a alleviates oxygen-glucose deprivation and reoxygenation-induced injury in neurons through regulation of GSK-3ß/Nrf2 signaling.

MicroRNAs (miRNAs) have been suggested as pivotal regulators in the pathological process of cerebral ischemia and reperfusion injury. In this study, we aimed to investigate the role of miR-135a in regulating neuronal survival in cerebral ischemia and reperfusion injury using an in vitro cellular model induced by oxygen-glucose deprivation and reoxygenation (OGD/R). Our results showed that miR-135a expression was significantly decreased in neurons with OGD/R treatment. Overexpression of miR-135a significantly alleviated OGD/R-induced cell injury and oxidative stress, whereas inhibition of miR-135a showed the opposite effects. Glycogen synthase kinase-3ß (GSK-3ß) was identified as a potential target gene of miR-135a. miR-135a was found to inhibit GSK-3ß expression, but promote the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and downstream signaling. However, overexpression of GSK-3ß significantly reversed miR-135a-induced neuroprotective effect. Overall, our results suggest that miR-135a protects neurons against OGD/R-induced injury through downregulation of GSK-3ß and upregulation of Nrf2 signaling.

Down-Regulation of IRF6 Protects Cortical Neurons Against Traumatic Neuronal Injury Through Activating Akt-eNOS Pathway.

Interferon regulatory factor 6 (IRF6) is a novel and unique member of the IRF family of transcription factors, and the regulation and function of IRF6 remain unknown. Recently, IRF6 was shown to be upregulated after TBI and could promote neuronal apoptosis under oxidative stress conditions. This study aimed to investigate the role of IRF6 in traumatic neuronal injury (TNI) in primary cultured mouse cortical neurons. We found that the expression of IRF6 was significantly increased within 48 after TNI, and peaked at 24 h. Knockdown of IRF6 using specific targeted small interfering RNA (siRNA) attenuated TNI-induced loss of neuronal viability and release of lactate dehydrogenase. The results of TUNEL staining showed that IRF6 knockdown markedly reduced neuronal apoptosis, which was accompanied by decreased activity of caspase-3. Furthermore, downregulation of IRF6 inhibited lipid peroxidation, promoted the activity of endogenous antioxidative enzymes, and differently regulated the expression of inflammatory cytokines after TNI. In addition, IRF6 knockdown significantly increased phosphorylation of Akt and endothelial nitric oxide synthase (eNOS), whereas blocking Akt-eNOS pathway via selective antagonists partly prevented the protective effects of IRF6 knockdown. These data show that downregulation of IRF6 affords protection against TNI through Akt-eNOS pathway-mediated antioxidative and anti-inflammatory activity.

SEPT7 overexpression inhibits glioma cell migration by targeting the actin cytoskeleton pathway.

Glioma cell metastasis is a serious obstacle for surgical treatment and prognosis, of which locomotion of the cytoskeleton is a key contributor of cancer cell spreading. SEPT7 is documented as a cytoskeletal protein with GTPase activity and involved in glioma progression. However, the underlying mechanism of SEPT7 in glioma invasion remains unresolved. Our study investigated whether SEPT7 influences glioma cell migration involved in cytoskeleton modulation. The SEPT7 expression in various glioma cell lines was markedly decreased compared to in normal human brain cells. It was demonstrated that SEPT7 overexpression significantly inhibits LN18 cell migration and chemotaxis induced by IGF­1 (P<0.01 and P<0.01). Moreover, MMP­2 and MMP­9 were dramatically depressed after SEPT7 upregulation. To understand the mechanisms by which SEPT7 modulates homeostasis of the actin cytoskeleton, the F­actin/G­actin ratio and cofilin expression were determined. The data revealed that the F­actin/G­actin ratio and cofilin were reduced, and p­cofilin increased conversely in cells with SEPT7 overexpression, indicating that SEPT7 reduced glioma cell migration by promoting cofilin phosphorylation and depolymerizing actin. Then, to understand the role of cofilin in SEPT7­mediated actin dynamic equilibrium and cell migration, cofilin siRNA was transfected into cells. Surprisingly, cell migration and actin polymerization which had been improved by SEPT7 siRNA were significantly reversed, and the accompanying cofilin phosphorylation increased, indicating that cofilin phospho­regulation played an important role in SEPT7­mediated cytoskeleton locomotion and glioma cell migration. In conclusion, SEPT7 is involved in glioma cell migration with the assistance of cofilin phospho­mediated cytoskeleton locomotion.