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Southwest China (SWC) possesses complicated topography with frequent geological activities, where heavy precipitation occurs frequently in warm seasons. Few previous studies on extreme precipitation were carried out at hourly scales. In this study, spatiotemporal variations of the extreme hourly precipitation (EHP) over SWC during the warm season of 1981-2020 and the involved mechanisms are investigated. Results show that the threshold and intensity of EHP present similar spatial distribution-lower (higher) in the west (east) part of SWC, while the EHP frequency is opposite. The long-term trend of EHP amount shows a more significant positive tendency than that of hourly precipitation (HP) amount due to synchronous increases in intensity and frequency. The significant increasing trend of EHP occurs in areas above 500-m terrain height, with a weak increasing trend below 500 m (e.g., Chongqing and eastern Sichuan). EHP appears mainly from June to August and exhibits a bimodal distribution in diurnal variation. The mechanism analysis demonstrates that occurrences of EHP are generally accompanied by positive anomalies of temperature, humidity, and geopotential height. Anomalous cyclonic circulation can also be found in the low-level wind field. The westward and northward extension of the western North Pacific subtropical high (WNPSH) as well as temperature rise may be the primary reason for the increase of EHP. For Chongqing and eastern Sichuan, the anticyclone circulation in low-level and the significantly weakened water vapor flux convergence cause poor moisture and dynamic conditions, inhibiting the growth of EHP. SIGNIFICANCE STATEMENT: Heavy precipitation occurs frequently during the warm season in Southwest China (SWC), often causing severe impacts on human safety and economic property. This study analyses spatiotemporal variations of the extreme hourly precipitation (EHP) over SWC during the warm season of 1981-2020 and the involved mechanisms. The increasing trend of EHP far exceeds that of hourly precipitation (HP), especially in areas above 500 m. The westward and northward extension of the western North Pacific subtropical high (WNPSH) and temperature rise may be the main reason for the increase of EHP. For areas below 500 m (e.g., Chongqing and eastern Sichuan), poor moisture and dynamic conditions inhibited the growth of EHP. [ABSTRACT FROM AUTHOR]

Yak is an important livestock animal for the people indigenous to the harsh, oxygen‐limited Qinghai‐Tibetan Plateau and Hindu Kush ranges of the Himalayas. The yak genome was sequenced in 2012, but its assembly was fragmented because of the inherent limitations of the Illumina sequencing technology used to analyse it. An accurate and complete reference genome is essential for the study of genetic variations in this species. Long‐read sequences are more complete than their short‐read counterparts and have been successfully applied towards high‐quality genome assembly for various species. In this study, we present a high‐quality chromosome‐scale yak genome assembly (BosGru_PB_v1.0) constructed with long‐read sequencing and chromatin interaction technologies. Compared to an existing yak genome assembly (BosGru_v2.0), BosGru_PB_v1.0 shows substantially improved chromosome sequence continuity, reduced repetitive structure ambiguity, and gene model completeness. To characterize genetic variation in yak, we generated de novo genome assemblies based on Illumina short reads for seven recognized domestic yak breeds in Tibet and Sichuan and one wild yak from Hoh Xil. We compared these eight assemblies to the BosGru_PB_v1.0 genome, obtained a comprehensive map of yak genetic diversity at the whole‐genome level, and identified several protein‐coding genes absent from the BosGru_PB_v1.0 assembly. Despite the genetic bottleneck experienced by wild yak, their diversity was nonetheless higher than that of domestic yak. Here, we identified breed‐specific sequences and genes by whole‐genome alignment, which may facilitate yak breed identification. [ABSTRACT FROM AUTHOR]

Background: The disease burden caused by pulmonary tuberculosis (TB) in Sichuan province still persisted at a high level, and large spatial variances were presented across regional distribution disparities. The socio-economic factors were suspected to affect the population of TB notification, we aimed to describe TB case notification rate (CNR) and identify which factors influence TB epidemic are necessary for the prevention and control of the disease in Sichuan province.Methods: A retrospective cross-sectional study and an ecological spatial analysis was conducted to quantify the presence and location of spatial clusters of TB by the Moran's I index and examined these patterns with socio-economic risk factors by hierarchical Bayesian spatio-temporal model.Results: A total of 630,009 pulmonary TB cases were notified from 2006 to 2015 in 181 counties of Sichuan province. The CNR decreased year by year since 2007, from 88.70 to 61.37 per 100,000 persons. The spatial heterogeneities of CNR were observed during the study periods. Global Moran's I index varied from 0.23 to 0.44 with all P-value < 0.001. The Bayesian spatio-temporal model with parametric spatio-temporal interactions was chosen as the best model according to the minimum of Deviance Information Criterion (DIC)(19,379.01), and in which the quadratic form of time was taken. The proportion of age group and education year were all associated with CNR after adjusting the spatial effect, temporal effect and spatio-temporal interactions. TB CNR increased by 10.2% [95% credible interval (CI): 6.7-13.7%] for every 1-standard-deviation increase in proportion of age group and decreased by 23% (95% CI: 13.7-32.7%) for every 1-standard-deviation increase in education year.Conclusions: There were spatial clusters of TB notification rate in Sichuan province from 2006 to 2015, and heavy TB burden was mainly attributed to aging and low socioeconomic status including poor education. Thus, it is more important to pay more attention to the elderly population and improve socioeconomic status including promoting education level in Sichuan province to reduce the TB burden. [ABSTRACT FROM AUTHOR]