The paper experimentally verifies the performance of Terrain-Aided Navigation (TAN) using an interferometric radio altimeter, which is recently used due to its accuracy. First, we propose a TAN system that utilizes an interferometric radio altimeter as a measurement system. Second, we implement extended Kalman filter, unscented Kalman filter, and particle filter to evaluate the performance of TAN according to the selection of filters and the difference of environments.

Objectives : β -Asarone (BAS) is an active ingredient in Acori Rhizoma. This study investigated anti-neuroinflammatory and memory ameliorating effects of BAS in systemic lipopolysaccharide (LPS)-treated C57BL/6 mice. Methods : BAS was administered orally at doses of 7.5, 15, and 30 mg/kg for 3 days prior to LPS (3 mg/kg, intraperitoneal) injection. Pro-inflammatory cytokine mRNA, including tumor necrosis factor-α (TNF-ㅍ), interleukin (IL)-1β and IL-6, was measured in hippocampus tissue using real-time polymerase chain reaction at 4 h after the LPS injection. An ameliorating effect of 30 mg/kg BAS on learning and memory impairment in the LPS-treated mice was verified using the Morris water maze test. Results : BAS significantly attenuated up-regulation of TNF-α , IL-1β , and IL-6 mRNA in hippocampus tissue of the LPS-treated mice. In acquisition training test, BAS improved learning performance of the LPS-treated mice with a significant decrease of escape latency to the platform. In memory retention test, BAS also ameliorated memory impairment of the LPS-treated mice with a significant increase of swimming time in zones neighboring to the platform, number of target heading, and memory score. Conclusion : The results suggest that inhibition of pro-inflammatory cytokines and neuroinflammation in the hippocampus by BAS could be one of the mechanisms for BAS-mediated ameliorating effect on learning and memory impairment in LPS-treated mice.

Objectives : Polygalae Radix (POL) has an ameliorating effect on learning and memory impairment caused by cerebral hypoperfusion. In regard to POL's action mechanism, this study was carried out to investigate the effects of POL on oxidative damage and neuronal apoptosis induced by cerebral hypoperfusion in rats. Methods : The cerebral hypoperfusion was induced by permanent bilateral common carotid artery occlusion (pBCAO) in Sprague-Dawley rats. POL was administered orally once a day (130 mg/kg of water-extract) for 28 days starting at 4 weeks after the pBCAO. Superoxide dismutase (SOD) activities and malondialdehyde (MDA) levels in the brain tissue were measured using ELISA method. Expressions of 4-hydroxynonenal (4HNE) and 8-hydroxy-2'-deoxyguanosine (8-OHdG) were observed using immunohistochemistry. In addition, neuronal apoptosis was evaluated with Cresyl violet staining, TUNEL labeling, and immunohistochemistry against Bax and caspase-3. Results : POL treatment significantly increased SOD activities and significantly reduced MDA levels in the cerebral cortex. The up-regulations of 4HNE and 8-OHdG expression caused by pBCAO in the CA1 of hippocampus were significantly attenuated by POL treatment. POL treatment also restored the reduction of CA1 thickness and CA1 neurons caused by pBCAO and significantly attenuated the apoptotic markers including TUNEL-positive cells, Bax, and caspase-3 expression in the CA1 of hippocampus. Conclusions : The results show that POL attenuated the oxidative damage in brain tissue and neuronal apoptosis in the hippocampus caused by the cerebral hypoperfusion. It suggests that POL can be a beneficial medicinal herb to treat the brain diseases related to cerebral hypoperfusion.