An Ultra-narrow Bandwidth Filter for Daytime Wind Measurement of Direct Detection Rayleigh Lidar

Han, Fei,Liu, Hengjia,Sun, Dongsong,Han, Yuli,Zhou, Anran,Zhang, Nannan,Chu, Jiaqi,Zheng, Jun,Jiang, Shan,Wang, Yuanzu Optical Society of Korea 2020 Current Optics and Photonics Vol.4 No.1

A Rayleigh Lidar used for wind detection works by transmitting laser pulses to the atmosphere and receiving backscattering signals from molecules. Because of the weak backscattering signals, a lidar usually uses a high sensitivity photomultiplier as detector and photon counting technology for signal collection. The capturing of returned extremely weak backscattering signals requires the lidar to work on dark background with a long time accumulation to get high signal-to-noise ratio (SNR). Because of the strong solar background during the day, the SNR of lidar during daytime is much lower than that during nighttime, the altitude and accuracy of detection are also restricted greatly. Therefore this article describes an ultra-narrow bandwidth filter (UNBF) that has been developed on 354.7 nm wavelength of laser. The UNBF is used for suppressing the strong solar background that degrades the performance of Rayleigh wind lidar during daytime. The optical structure of UNBF consists of an interference filter (IF), a low resolution Fabry-Perot interferometer (FPI) and a high resolution FPI. The parameters of each optical component of the UNBF are presented in this article. The transmission curve of the aligned UNBF is measured with a tunable laser. Contrasting the result of with-UNBF and with-IF shows that the solar background received by a Licel transient recorder decreases by 50~100 times and that the SNR with-UNBF was improved by 3 times in the altitude range (35 km to 40 km) compared to with-IF at 10:26 to 10:38 on August 29, 2018. By the SNR comparison at four different times of one day, the ratio-values are larger than 1 over the altitude range (25~50 km) in general, the results illustrate that the SNR with-UNBF is better than that with-IF for Rayleigh Lidar during daytime and they demonstrate the effective improvements of solar background restriction of UNBF.

Ginsenoside Rg1 alleviates A deposition by inhibiting NADPH oxidase 2 activation in APP/PS1 mice

Han Zhang,Yong Su,Zhenghao Sun,Ming Chen,Yuli Han,Yan Li,Xianan Dong,Shixin Ding,Zhirui Fang,Weiping Li,Weizu Li 고려인삼학회 2021 Journal of Ginseng Research Vol.45 No.6

Background: Ginsenoside Rg1 (Rg1), an active ingredient in ginseng, may be a potential agent for thetreatment of Alzheimer’s disease (AD). However, the protective effect of Rg1 on neurodegeneration in ADand its mechanism of action are still incompletely understood. Methods: Wild type (WT) and APP/PS1 AD mice, from 6 to 9 months old, were used in the experiment. The open field test (OFT) and Morris water maze (MWM) were used to detect behavioral changes. Neuronal damage was assessed by hematoxylin and eosin (H&E) and Nissl staining. Immunofluorescence,western blotting, and quantitative real-time polymerase chain reaction (q-PCR) were used toexamine postsynaptic density 95 (PSD95) expression, amyloid beta (Ab) deposition, Tau and phosphorylatedTau (p-Tau) expression, reactive oxygen species (ROS) production, and NAPDH oxidase 2(NOX2) expression. Results: Rg1 treatment for 12 weeks significantly ameliorated cognitive impairments and neuronaldamage and decreased the p-Tau level, amyloid precursor protein (APP) expression, and Ab generation inAPP/PS1 mice. Meanwhile, Rg1 treatment significantly decreased the ROS level and NOX2 expression inthe hippocampus and cortex of APP/PS1 mice. Conclusions: Rg1 alleviates cognitive impairments, neuronal damage, and reduce Ab deposition byinhibiting NOX2 activation in APP/PS1 mice.

Ginsenoside Rg1 attenuates cerebral ischemia-reperfusion injury due to inhibition of NOX2- mediated calcium homeostasis dysregulation in mice

Yuli Han,Xuewang Li,Liu Yang,Duoduo Zhang,Lan Li,Xianan Dong,Yan Li,Sen Qun,Weizu Li 고려인삼학회 2022 Journal of Ginseng Research Vol.46 No.4

Background: The incidence of ischemic cerebrovascular disease is increasing in recent years and has beenone of the leading causes of neurological dysfunction and death. Ginsenoside Rg1 has been found toprotect against neuronal damage in many neurodegenerative diseases. However, the effect and mechanismby which Rg1 protects against cerebral ischemia-reperfusion injury (CIRI) are not fully understood. Here, we report the neuroprotective effects of Rg1 treatment on CIRI and its possible mechanisms inmice. Methods: A bilateral common carotid artery ligation was used to establish a chronic CIRI model in mice. HT22 cells were treated with Rg1 after OGD/R to study its effect on [Ca2þ]i. The open-field test and poleclimbingexperiment were used to detect behavioral injury. The laser speckle blood flowmeter was usedto measure brain blood flow. The Nissl and H&E staining were used to examine the neuronal damage. TheWestern blotting was used to examine MAP2, PSD95, Tau, p-Tau, NOX2, PLC, p-PLC, CN, NFAT1, and NLRP1expression. Calcium imaging was used to test the level of [Ca2þ]i. Results: Rg1 treatment significantly improved cerebral blood flow, locomotion, and limb coordination,reduced ROS production, increased MAP2 and PSD95 expression, and decreased p-Tau, NOX2, p-PLC, CN,NFAT1, and NLRP1 expression. Calcium imaging results showed that Rg1 could inhibit calcium overloadand resist the imbalance of calcium homeostasis after OGD/R in HT22 cells. Conclusion: Rg1 plays a neuroprotective role in attenuating CIRI by inhibiting oxidative stress, calciumoverload, and neuroinflammation.

An Ultra-narrow Bandwidth Filter for Daytime Wind Measurement of Direct Detection Rayleigh Lidar

Fei Han,Hengjia Liu,Dongsong Sun,Yuli Han,Anran Zhou,Nannan Zhang,Jiaqi Chu,Jun Zheng,Shan Jiang,Yuanzu Wang 한국광학회 2020 Current Optics and Photonics Vol.4 No.1

A Rayleigh Lidar used for wind detection works by transmitting laser pulses to the atmosphere and receiving backscattering signals from molecules. Because of the weak backscattering signals, a lidar usually uses a high sensitivity photomultiplier as detector and photon counting technology for signal collection. The capturing of returned extremely weak backscattering signals requires the lidar to work on dark background with a long time accumulation to get high signal-to-noise ratio (SNR). Because of the strong solar background during the day, the SNR of lidar during daytime is much lower than that during nighttime, the altitude and accuracy of detection are also restricted greatly. Therefore this article describes an ultra-narrow bandwidth filter (UNBF) that has been developed on 354.7 nm wavelength of laser. The UNBF is used for suppressing the strong solar background that degrades the performance of Rayleigh wind lidar during daytime. The optical structure of UNBF consists of an interference filter (IF), a low resolution Fabry-Perot interferometer (FPI) and a high resolution FPI. The parameters of each optical component of the UNBF are presented in this article. The transmission curve of the aligned UNBF is measured with a tunable laser. Contrasting the result of with-UNBF and with-IF shows that the solar background received by a Licel transient recorder decreases by 50~100 times and that the SNR with-UNBF was improved by 3 times in the altitude range (35 km to 40 km) compared to with-IF at 10:26 to 10:38 on August 29, 2018. By the SNR comparison at four different times of one day, the ratio-values are larger than 1 over the altitude range (25~50 km) in general, the results illustrate that the SNR with-UNBF is better than that with-IF for Rayleigh Lidar during daytime and they demonstrate the effective improvements of solar background restriction of UNBF.

Performance of Continuous-wave Coherent Doppler Lidar for Wind Measurement

Shan Jiang,Dongsong Sun,Yuli Han,Fei Han,Anran Zhou,Jun Zheng 한국광학회 2019 Current Optics and Photonics Vol.3 No.5

A system for continuous-wave coherent Doppler lidar (CW lidar), made up of all-fiber structures and a coaxial transmission telescope, was set up for wind measurement in Hefei (31.84 N, 117.27 E), Anhui province of China. The lidar uses a fiber laser as a light source at a wavelength of 1.55 µm, and focuses the laser beam on a location 80 m away from the telescope. Using the CW lidar, radial wind measurement was carried out. Subsequently, the spectra of the atmospheric backscattered signal were analyzed. We tested the noise and obtained the lower limit of wind velocity as 0.721 m/s, through the Rayleigh criterion. According to the number of Doppler peaks in the radial wind spectrum, a classification retrieval algorithm (CRA) combining a Gaussian fitting algorithm and a spectral centroid algorithm is designed to estimate wind velocity. Compared to calibrated pulsed coherent wind lidar, the correlation coefficient for the wind velocity is 0.979, with a standard deviation of 0.103 m/s. The results show that CW lidar offers satisfactory performance and the potential for application in wind measurement.

스마트 헬스 시티 구현을 위한 얼굴 영상기반 심박수 추출 딥러닝 모델 최적화

김광호(Gwangho Kim),Yuli Sun Hariyani,한승우(Seungwoo Han),이현빈(HyeonBin Lee),손량희(Ryanghee Sohn),박철수(Cheolsoo Park) 한국통신학회 2020 韓國通信學會論文誌 Vol.45 No.12

Scanning Rayleigh Doppler Lidar for Wind Profiling Based on Non-polarized Beam Splitter Cube Optically Contacted FPI

Jun Zheng,Dongsong Sun,Tingdi Chen,Ruocan Zhao,Yuli Han,Zimu Li,Anran Zhou,Nannan Zhang 한국광학회 2018 Current Optics and Photonics Vol.2 No.2

A Scanning Rayleigh Doppler lidar for wind profiling based on a non-polarized beam splitter cube optically contacted FPI is developed for wind measurement from high troposphere to low stratosphere in 5-35 km. Non-polarized beam splitter cube optically contacted to the FPI are used for a stable optical receiver. Zero Doppler shift correction is used to correct for laser or FPI frequency jitter and drift and the timing sequence is designed. Stability of the receiver for Doppler shift discrimination is validated by measuring the transmissions of FPI in different days and analyzed the response functions. The maximal relative wind deviation due to the stability of the optical receiver is about 4.1% and the standard deviation of wind velocity is 1.6% due to the stability. Wind measurement comparison experiments were carried out in Jiuquan (39.741°N, 98.495°E), Gansu province of China in 2015, showing good agreement with radiosonde result data. Continuous wind field observation was performed from October 16th to November 12th and semi-continuous wind field of 19 nights are presented.