Satellite mobile system and space-airground integrated network have a prominent superiority in global coverage which plays a critical role in remote and non-land regions, as well as emergency communications. However, ...Satellite mobile system and space-airground integrated network have a prominent superiority in global coverage which plays a critical role in remote and non-land regions, as well as emergency communications. However, due to the gradual angle attenuations of the satellite antennas, it is difficult to achieve full frequency multiplex among different beams as terrestrial 5G network. Multi-color frequency reuse is widely adopted in both academic and industry. Beam hopping scheme has attracted the attention of researchers recently due to the allocation flexibility. In this paper, we focus on analyzing the performance benefits of beam hopping compared with multi-color frequency reuse scheme in non-uniform user and traffic distributions in satellite system. Aerial networks are also introduced to form a space-airground integrated network for coverage enhancement,and the capacity improvement is analyzed. Besides,additional improved techniques are provided to make comprehensive analysis and comparisons. Theoretical analysis and simulation results indicate that the beam hopping scheme has a prominent superiority in the system capacity compared with the traditional multicolor frequency reuse scheme in both satellite mobile system and future space-air-ground integrated network.展开更多
Continuous recording of precipitation and soil water content（SWC）, especially during long periods of torrential rainfall, has proven challenging. Over a 16 h period spanning 21-22 July, 2012, Beijing experienced his...Continuous recording of precipitation and soil water content（SWC）, especially during long periods of torrential rainfall, has proven challenging. Over a 16 h period spanning 21-22 July, 2012, Beijing experienced historic rainfall that totaled 164.4 mm. We used large lysimeter technology in four forested plots to record precipitation and variation in SWC at 10-min intervals to quantify the response of forestland SWC to heavy rainfall in a semi-arid area. Mean,maximum and minimum rainfall intensities were 23.4, 46.8and 12.0 mm/h, respectively. Rainfall was concentrated in 2-6 mm bursts that accounted for 67.32 % of the total rainfall event. Soil moisture conditions in this region are strongly dependent on patterns of precipitation. Water infiltration into 20, 40, 60, 80, 100, 120 and 160 cm soil layers required 1, 5,20, 37, 46, 52 and 61 mm of precipitation, respectively, and to fully saturate these soil layers required 80, 120, 140, 150, 180,200 and 220 mm of precipitation, respectively.展开更多
Bile acids(BAs)play a crucial role in nutrient absorption and act as key regulators of lipid and glucose metabolism and immune homeostasis.Through the enterohepatic circulation,BAs are synthesized,metabolized,and reab...Bile acids(BAs)play a crucial role in nutrient absorption and act as key regulators of lipid and glucose metabolism and immune homeostasis.Through the enterohepatic circulation,BAs are synthesized,metabolized,and reabsorbed,with a portion entering the vascular circulation and distributing systemically.This allows BAs to interact with receptors in all major organs,leading to organ-organ interactions that regulate both local and global metabolic processes,as well as the immune system.This review focuses on the whole-body effects of BA-mediated metabolic and immunological regulation,including in the brain,heart,liver,intestine,eyes,skin,adipose tissue,and muscle.Targeting BA synthesis and receptor signaling is a promising strategy for the development of novel therapies for various diseases throughout the body.展开更多
基金the Natural Science Foundation of China under Grant 61801319Sichuan Science and Technology Program under Grant 2020JDJQ0061+1 种基金the Education Agency Project of Sichuan Province under Grant 18ZB0419the Sichuan University of Science and Engineering Talent Introduction Project under Grant 2020RC33。
文摘Satellite mobile system and space-airground integrated network have a prominent superiority in global coverage which plays a critical role in remote and non-land regions, as well as emergency communications. However, due to the gradual angle attenuations of the satellite antennas, it is difficult to achieve full frequency multiplex among different beams as terrestrial 5G network. Multi-color frequency reuse is widely adopted in both academic and industry. Beam hopping scheme has attracted the attention of researchers recently due to the allocation flexibility. In this paper, we focus on analyzing the performance benefits of beam hopping compared with multi-color frequency reuse scheme in non-uniform user and traffic distributions in satellite system. Aerial networks are also introduced to form a space-airground integrated network for coverage enhancement,and the capacity improvement is analyzed. Besides,additional improved techniques are provided to make comprehensive analysis and comparisons. Theoretical analysis and simulation results indicate that the beam hopping scheme has a prominent superiority in the system capacity compared with the traditional multicolor frequency reuse scheme in both satellite mobile system and future space-air-ground integrated network.
基金The National Natural Science Foundation of China(No.4143074741401013)
文摘Continuous recording of precipitation and soil water content（SWC）, especially during long periods of torrential rainfall, has proven challenging. Over a 16 h period spanning 21-22 July, 2012, Beijing experienced historic rainfall that totaled 164.4 mm. We used large lysimeter technology in four forested plots to record precipitation and variation in SWC at 10-min intervals to quantify the response of forestland SWC to heavy rainfall in a semi-arid area. Mean,maximum and minimum rainfall intensities were 23.4, 46.8and 12.0 mm/h, respectively. Rainfall was concentrated in 2-6 mm bursts that accounted for 67.32 % of the total rainfall event. Soil moisture conditions in this region are strongly dependent on patterns of precipitation. Water infiltration into 20, 40, 60, 80, 100, 120 and 160 cm soil layers required 1, 5,20, 37, 46, 52 and 61 mm of precipitation, respectively, and to fully saturate these soil layers required 80, 120, 140, 150, 180,200 and 220 mm of precipitation, respectively.
基金supported by the National Natural Science Foundation of China(82122012,82270917)Shanghai Research Center for Endocrine and Metabolic Diseases(2022ZZ01002)。
文摘Bile acids(BAs)play a crucial role in nutrient absorption and act as key regulators of lipid and glucose metabolism and immune homeostasis.Through the enterohepatic circulation,BAs are synthesized,metabolized,and reabsorbed,with a portion entering the vascular circulation and distributing systemically.This allows BAs to interact with receptors in all major organs,leading to organ-organ interactions that regulate both local and global metabolic processes,as well as the immune system.This review focuses on the whole-body effects of BA-mediated metabolic and immunological regulation,including in the brain,heart,liver,intestine,eyes,skin,adipose tissue,and muscle.Targeting BA synthesis and receptor signaling is a promising strategy for the development of novel therapies for various diseases throughout the body.
