| 1 | Study of the Retinal Imaging and Output in Premature Baby under a Computer-assisted Binocular Indirect Ophthalmoscope显示文摘Purpose:To explore a clear retinal imaging and output and enhance the development of retinopathy of prematurity (ROP) screening,which is safe and effective for ROP screening in premature infants. Methods:A computer-assisted binocular indirect ophthalmoscope imaging and output system was equipped with camera and image processing hardware and connected to computers. The process of fundus examination was videotaped (photograph) and output. Simulated eyes were utilized to debug video head and acquire stable and clear fundus images by binocular indirect ophthalmoscope for premature infants. Results:Fundus imaging output technique was sucessfully established. The common reasons of unclear imaging and corresponding solutions were summarized. This technique can capture and output stable and clear fundus images of premature infants. Conclusion: Assisted by hardware and software processing, a compute assisted binocular indirect ophthalmoscope imaging and output system was established,which can be used for screening, research, treatment and follow-up of ROP in premature babies to resolve the difficulty in obtaining clear fundus photograph. | Daoman Xiang Feng Chen Jianxun Wang Zheng Guo Lihong Chen Yani Mao | 2012 | Eye Science2012,27,4: | 3 |
| 2 | Influences of MJO-induced Tropical Cyclones on the Circulation-Convection Inconsistency for the 2021 South China Sea Summer Monsoon Onset显示文摘The South China Sea Summer Monsoon(SCSSM)onset is characterized by an apparent seasonal conversion of circulation and convection.Accordingly,various indices have been introduced to identify the SCSSM onset date.However,the onset dates as determined by various indices can be very inconsistent.It not only limits the determination of onset dates but also misleads the assessment of prediction skills.In 2021,the onset time as identified by the circulation criteria was 20 May,which is 12 days earlier than that deduced by also considering the convection criteria.The present study mainly ascribes such circulation-convection inconsistency to the activities of tropical cyclones(TCs)modulated by the Madden-Julian Oscillation(MJO).The convection of TC“Yaas”(2021)acted as an upper-level diabatic heat source to the north of the SCS,facilitating the circulation transition.Afterward,TC“Choi-wan”(2021)over the western Pacific aided the westerlies to persist at lower levels while simultaneously suppressing moist convection over the SCS.Accurate predictions using the ECMWF S2S forecast system were obtained only after the MJO formation.The skillful prediction of the MJO during late spring may provide an opportunity to accurately predict the establishment of the SCSSM several weeks in advance. | Yanying CHEN Ning JIANG Yang AI Kang XU Longjiang MAO | 2023 | Advances in Atmospheric Sciences2023,40,2: | 0 |
| 3 | Spatiotemporal Drought Assessment over Sahelian Countries from 1985 to 2015显示文摘Due to infrequent rainfall, high temperatures, and degraded land, the Sahel region often suffers from droughts. The Sahel region is considered as one of the world’s driest and extreme environmental conditions. In order to assess spatiotemporal vulnerability of potential drought impacts, we used remote sensing and ground station data to evaluate drought conditions in the Sahel region from 1985 to 2015. The standard precipitation index(SPI), standard precipitation evapotranspiration index(SPEI), vegetation condition index(VCI) anomaly, along with socioeconomic indicators were performed. In addition, Pearson correlation coefficient(PCC) was computed between drought indices and three main crops(sorghum, millet, and maize) in the region to estimate the effects. The analysis showed that temperature increased by 0.78°C from 1985 to 2015, which had a significant impact on crop yield for sorghum, maize, and millet with a statistical significance value of P > 0.05. In the decade spanning 1994 to 2005 alone, the temperature increased by 0.57°C, which resulted in extreme drought in Algeria, Sudan, Chad, Nigeria, and Mauritania. For the effect of drought on crop production, high significance was noted on the SPI and SPEI-3 timescale: sorghum with SPI-3(r = 0.71) and SPEI-3(r = 0.65), millet with SPI-3(r = 0.61) and SPEI-3(r = 0.72), and maize with SPI-3(r =0.81) and SPEI-3(r = 0.65) during the study period. In the growing season, VCI anomaly had strong correlations with sorghum and millet(r = 0.67 and 0.75, respectively). A significant agreement was also noticed between the combined drought index(CDI) and vulnerability index(VI) in Burkina Faso(r =-0.676;P < 0.00), Mali(r =-0.768;P < 0.00), Mauritania(r = 0.843;P < 0.001), Niger(r =-0.625;P < 0.001), and Nigeria(r =-0.75;P < 0.005). The results show that the above indices are effective in assessing agricultural drought and its impact on crop production in the Sahel, and in identifying areas most affected by drought. | Nusseiba NOURELDEEN Kebiao MAO Alnail MOHMMED Zijin YUAN Yanying YANG | 2020 | Journal of Meteorological Research2020,34,4: | 0 |