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The climate effect and environmental pollution caused by dust discharged into the atmosphere have attracted much attention. However, the driving factors of dust emissions have not been studied thoroughly. Here, spatiotemporal variations in dust emissions and the relationship between dust emissions and large-scale atmospheric circulation in East Asia from 2000 to 2021 were investigated using Modern-Era Retrospective Analysis for Research and Applications version 2, Cloud-Aerosol Lidar Pathfinder Satellite Observations, ERA5 reanalysis data, and climate indices. Results showed that the Taklimakan Desert in the Tarim Basin, the Gurbantonggut Desert in the Junggar Basin, the Turpan Basin, and the Gobi Desert in western Inner Mongolia and southern Mongolia are the main sources of dust emissions in East Asia. The period of strong dust emissions is from March to May, and emissions to the atmosphere were mainly distributed at 0–4 km in the troposphere. In the eastern and southwestern Tarim Basin, northern Junggar Basin, and parts of the Gobi Desert in southern Mongolia, dust emissions have significantly increased over the past 22 years, whereas in the southwestern Tibetan Plateau, southwestern Inner Mongolia, and a small part of the northern Mongolian Gobi Desert there was a significant decreasing trend. The winter North Atlantic Oscillation (NAO) and Arctic Oscillation (AO) were significantly negatively correlated with East Asian dust emissions the following spring. The various phases of the AO/NAO coupling have clear different effects on East Asian dust emissions in the spring. When the AO/NAO coupling was negative (positive), the East Asian trough and Siberian High were strengthened (weakened), the frequency of cold air activity increased (weakened), 800 hPa wind speed strengthened (weakened), and East Asian emissions increased (decreased). In AO−/NAO+ years, the Asian polar vortex was stronger to the south and the East Asian trough was stronger to the west. The Lake Baikal trough was in the deepening phase, which caused more polar cold air to move into East Asia, aggravating the intensity of dust activity. In the AO+/NAO− years, the Siberian High and East Asian trough weakened, which was unfavorable to the southward movement of cold air from Siberia. Therefore, the frequency of windy weather in East Asia decreased, partly weakening dust emissions. However, a positive geopotential anomaly in northeast China and a negative geopotential anomaly in South Asia triggered an anomalous enhancement in easterly wind in the tropospheric area over northwest China. Strengthening of the Balkhash trough provides favorable conditions for gale weather in northwest China. The frequency of gale weather increased, and dust emissions were enhanced in northwest China. [ABSTRACT FROM AUTHOR]

Understanding the effects of zonal variation of the East Asian subtropical westerly jet (EAWJ) on spatial features of heavy precipitation events requires characterization of the shape, orientation, position, and scale of both the EAWJ and rain belts. Applying a rotating calipers algorithm, jet-axis tracking, wavelet analysis, and K-means clustering algorithm, spatial structures of both the EAWJ and rain belts were quantified for each heavy rainfall event lasting 3 days (3-day-HRE) in 1983–2020. The results reveal that approximately 90% of the EAWJs related to 3-day-HREs had a statistically significant wave structure of ∼6000–12 000 km over East Asia and the North Pacific. These EAWJs had tilted, wavy, and flat patterns and strongly affected the position, orientation, and spatial scales of the 3-day-HRE rain belts by modifying the vapor transport trajectory and vertical rising motions. All types of EAWJ had an orientation similar to that of the rain belts and an average distance to the rain belts of ∼500–1500 km at 105°–125°E and ∼500 km at 125°E–180°. Correspondingly, the rain belts of 3-day-HREs had the largest frequency over eastern China and southern Japan. Zonally asymmetric Rossby waves arising from the land–sea thermal contrast, atmospheric diabatic heating, and topography dominantly contributed to the formation of a meandering or flat EAWJ. A zonally oscillating trough–ridge system, featuring an equivalent barotropic structure with large geopotential height anomalies reaching the lower troposphere, weakens or blocks vapor transport and is ultimately responsible for the strongly varying spatial scales and orientations of rain belts. Significance Statement: A solid theoretical basis that variations in the EAWJ intimately covary with the location and orientation of rain belts means that understanding the relationships between the EAWJ's zonal variations and the spatial features of monsoonal rain belts is conducive to better predicting the weather and climate over East Asia. We quantitatively explored the effects of EAWJ zonal variations on the position, orientation, and scale of rain belts and found that a tilted, wavy, or relatively flat pattern of the EAWJ strongly affected the rain belt spatial features by modifying the vapor transport trajectory. A zonally oscillating trough–ridge system, featuring an equivalent barotropic structure throughout the troposphere, is responsible for the varying spatial scale of rain belts. [ABSTRACT FROM AUTHOR]

Background: Pyropia is an economically advantageous genus of red macroalgae, which has been cultivated in the coastal areas of East Asia for over 300 years. Realizing estimation of macroalgae biomass in a high-throughput way would great benefit their cultivation management and research on breeding and phenomics. However, the conventional method is labour-intensive, time-consuming, manually destructive, and prone to human error. Nowadays, high-throughput phenotyping using unmanned aerial vehicle (UAV)-based spectral imaging is widely used for terrestrial crops, grassland, and forest, but no such application in marine aquaculture has been reported. Results: In this study, multispectral images of cultivated Pyropia yezoensis were taken using a UAV system in the north of Haizhou Bay in the midwestern coast of Yellow Sea. The exposure period of P. yezoensis was utilized to prevent the significant shielding effect of seawater on the reflectance spectrum. The vegetation indices of normalized difference vegetation index (NDVI), ratio vegetation index (RVI), difference vegetation index (DVI) and normalized difference of red edge (NDRE) were derived and indicated no significant difference between the time that P. yezoensis was completely exposed to the air and 1 h later. The regression models of the vegetation indices and P. yezoensis biomass per unit area were established and validated. The quadratic model of DVI (Biomass = − 5.550DVI2 + 105.410DVI + 7.530) showed more accuracy than the other index or indices combination, with the highest coefficient of determination (R2), root mean square error (RMSE), and relative estimated accuracy (Ac) values of 0.925, 8.06, and 74.93%, respectively. The regression model was further validated by consistently predicting the biomass with a high R2 value of 0.918, RMSE of 8.80, and Ac of 82.25%. Conclusions: This study suggests that the biomass of Pyropia can be effectively estimated using UAV-based spectral imaging with high accuracy and consistency. It also implied that multispectral aerial imaging is potential to assist digital management and phenomics research on cultivated macroalgae in a high-throughput way. [ABSTRACT FROM AUTHOR]

The potential values of Chinese herbal formulas in treating various diseases are well known. In addition to more than 2,000 years of history, herbal medicine is appreciated for its remarkable efficacy in a lot of cases, which warrants a role in public health care worldwide, especially in East Asian countries. Liver cancer is the second most fatal cancer across the world. Recent studies have extensively investigated the chemical profiles and pharmacological effects of Chinese herbal medicine formulas on liver cancer. Either through observational follow-up or experimental studies, multiple herbal formulas have benefits implicated in the management of liver cancer. However, complex composition of each formula imposes restrictions on promoting clinical practice and global recognition. Therefore, understanding the mode of action of Chinese herbal medicine formulas in depth may offer sufficient evidence for their clinical use. This review highlighted the chemical characteristics and molecular mechanisms of actions of prominent Chinese herbal medicine formulas and summarized the correlated findings on the potential use in liver cancer treatment. At last, the present progresses of Chinese herbal medicine formulas in the perspective of clinical trials are discussed. [ABSTRACT FROM AUTHOR]

The variation of the East Asian jet stream (EAJS) associated with the Eurasian (EU) teleconnection pattern is investigated using 60-yr NCEP-NCAR daily reanalysis data over the period 1951-2010. The EAJS consists of three components: the polar front jet (PFJ); the plateau subtropical jet (PSJ); and the ocean subtropical jet (OSJ). Of these three jets over East Asia, the EU pattern exhibits a significant influence on the PFJ and OSJ. There is a simultaneous negative correlation between the EU pattern and the PFJ. A significant positive correlation is found between the EU pattern and the OSJ when the EU pattern leads the OSJ by about 5 days. There is no obvious correlation between the EU pattern and the PSJ. The positive EU phase is accompanied by a weakened and poleward-shifted PFJ, which coincides with an intensified OSJ. A possible mechanism for the variation of the EAJS during different EU phases is explored via analyzing the effects of 10-day high-and low-frequency eddy forcing. The zonal wind tendency due to high-frequency eddy forcing contributes to the simultaneous negative correlation between the EU pattern and the PFJ, as well as the northward/southward shift of the PFJ. High- and low-frequency eddy forcing are both responsible for the positive correlation between the EU pattern and the OSJ, but only high-frequency eddy forcing contributes to the lagged variation of the OSJ relative to the EU pattern. The negative correlation between the EU pattern and winter temperature and precipitation anomalies in China is maintained only when the PFJ and OSJ are out of phase with each other. Thus, the EAJS plays an important role in transmitting the EU signal to winter temperature and precipitation anomalies in China. [ABSTRACT FROM AUTHOR]

Simple Summary: The genus Lycoris (Amaryllidaceae) comprises about 20 species with high ornamental and medicinal value. However, germplasm identification is still difficult due to frequent interspecific hybridization and intraspecific morphological variation within this genus. Plastid genome sequencing has been proven to be a useful tool to identify closely related species and is widely used in the field of plant evolution and phylogeny. In the present study, we provided four chloroplast genomes of Lycoris and retrieved seven published species in the genus for comparative genomics and phylogenetic analyses. All these chloroplast genomes possess the typical quadripartite structure with conserved genome arrangement and gene content, yet their lengths varied due to expansion/contraction of the IR/SC boundaries. Phylogenetic relationships within Lycoris were resolved with high resolution using complete cp genome sequences. These results could not only offer a genome-scale platform for identification and utilization of Lycoris but also provide a phylogenomic framework for future studies in this genus. The genus Lycoris (Amaryllidaceae) consists of about 20 species, which is endemic to East Asia. Although the Lycoris species is of great horticultural and medical importance, challenges in accurate species identification persist due to frequent natural hybridization and large-scale intraspecific variation. In this study, we sequenced chloroplast genomes of four Lycoris species and retrieved seven published chloroplast (cp) genome sequences in this genus for comparative genomic and phylogenetic analyses. The cp genomes of these four newly sequenced species were found to be 158,405–158,498 bp with the same GC content of 37.8%. The structure of the genomes exhibited the typical quadripartite structure with conserved gene order and content. A total of 113 genes (20 duplicated) were identified, including 79 protein-coding genes (PCGs), 30 tRNAs, and 4 rRNAs. Phylogenetic analysis showed that the 11 species were clustered into three main groups, and L. sprengeri locate at the base of Lycoriss. The L. radiata was suggested to be the female donor of the L. incarnata, L. shaanxiensis, and L. squamigera. The L. straminea and L. houdyshelii may be derived from L. anhuiensis, L. chinensis, or L. longituba. These results could not only offer a genome-scale platform for identification and utilization of Lycoris but also provide a phylogenomic framework for future studies in this genus. [ABSTRACT FROM AUTHOR]

Northern China is a significant source of dust source in Central Asia. Thus, high-resolution analysis of dust storms and comparison of dust sources in different regions of northern China are important to clarify the formation mechanism of East Asian dust storms and predict or even prevent such storms. Here, we analyzed spatiotemporal trends in dust storms that occurred in three main dust source regions during 1960–2007: Taklimakan Desert (western region [WR]), Badain Jaran and Tengger Deserts (middle region [MR]), and Otindag Sandy Land (eastern region [ER]). We analyzed daily dust storm frequency (DSF) at the 10-day scale (first [FTDM], middle [MTDM], and last [LTDM] 10 days of a month), and investigated the association of dust storm occurrences with meteorological factors. The 10-day DSF was greatest in the FTDM (accounting for 77.14% of monthly occurrences) in the WR, MTDM (45.85%) in the MR, and LTDM (72.12%) in the ER, showing a clear trend of movement from the WR to the ER. Temporal analysis of DSF revealed trend changes over time at annual and 10-day scales, with mutation points at 1985 and 2000. We applied single-factor and multiple-factor analyses to explore the driving mechanisms of DSF at the 10-day scale. Among single factors, a low wind-speed threshold, high solar radiation, and high evaporation were correlated with a high DSF, effectively explaining the variations in DSF at the 10-day scale; however, temperature, relative humidity, and precipitation poorly explained variations in DSF. Similarly, multiple-factor analysis using a classification and regression tree revealed that maximum wind speed was a major influencing factor of dust storm occurrence at the 10-day scale, followed by relative humidity, evaporation, and solar radiation; temperature and precipitation had weak influences. These findings help clarify the mechanisms of dust storm occurrence in East Asia. Image 1 • Dust storm frequency declined eastward in three desert regions of northern China. • Dust storm frequency and intensity trends changed over time during 1960–2007. • Wind speed, humidity, evaporation, and solar radiation influence dust storms. • Temperature and precipitation do not influence dust storm occurrence. [ABSTRACT FROM AUTHOR]