Concurrent extreme weather events in geographically distant areas potentially cause high-end risks for societies.By using network analysis,the present study managed to identify significant nearly-simultaneous occurren...Concurrent extreme weather events in geographically distant areas potentially cause high-end risks for societies.By using network analysis,the present study managed to identify significant nearly-simultaneous occurrences of heatwaves between the grid cells in East Asia and Eastern Europe,even though they are geographically far away from each other.By further composite analysis,this study revealed that hot events first occurred in Eastern Europe,typically with a time lag of3-4 days before the East Asian heatwave events.An eastward propagating atmospheric wave train,known as the circumglobal teleconnection(CGT)pattern,bridged the sequent occurrences of extreme events in these two remote regions.Atmospheric blockings,amplified by surface warming over Eastern Europe,not only enhanced local heat extremes but also excited a CGT-like pattern characterized by alternative anomalies of high and low pressures.Subsequent downstream anticyclones in the middle and upper troposphere reduced local cloud cover and increased downward solar radiation,thereby facilitating the formation of heatwaves over East Asia.Nearly half of East Asian heatwave events were preceded by Eastern European heatwave events in the 10-day time range before East Asian heatwave events.This investigation of heatwave teleconnection in the two distant regions exhibits strong potential to improve the prediction accuracy of East Asian heatwaves.展开更多
With the increase in the aging population,the global number of people with Alzheimer’s disease(AD)progressively increased worldwide.The situation is aggravated by the fact that there is no the efective pharmacologica...With the increase in the aging population,the global number of people with Alzheimer’s disease(AD)progressively increased worldwide.The situation is aggravated by the fact that there is no the efective pharmacological therapy of AD.Photobiomodulation(PBM)is non-pharmacological approach that has shown very promising results in the therapy of AD in pilot clinical and animal studies.However,the mechanisms of therapeutic efects of PBM for AD are poorly understood.In this study on mice,we demonstrate that photodynamic efects of 5-aminolevulenic acid and laser 635 nm cause reduction of network of the meningeal lymphatic vessels(MLVs)leading to suppression of lymphatic removal of beta-amyloid(Aβ)from the right lateral ventricle and the hippocampus.Using the original protocol of PBM under electroencephalographic monitoring of wakefulness and sleep stages in non-anesthetized mice,we discover that the 7-day course of PBM during deep sleep vs.wakefulness provides better restoration of clearance of Aβfrom the ventricular system of the brain and the hippocampus.Our results shed light on the mechanism of PBM and show the stimulating efects of PBM on the brain lymphatic drainage that promotes transport of Aβvia the lymphatic pathway.The efects of PBM on the brain lymphatics in sleeping brain open a new niche in the study of restorative functions of sleep as well as it is an important informative platform for the development of innovative smart sleep technologies for the therapy of AD.展开更多
Large-amplitude rolling motions, also regarded as extreme oscillations, are a great threat to marine navigation, which may lead to capsizing in ship motion. Therefore, it is important to quantify extreme oscillations,...Large-amplitude rolling motions, also regarded as extreme oscillations, are a great threat to marine navigation, which may lead to capsizing in ship motion. Therefore, it is important to quantify extreme oscillations, assess reliability of ship systems, and establish a suitable indicator to characterize extreme oscillations in ship systems. In this work, extreme events are investigated in a ship model considering a complex ocean environment, described by a single-degree-of-freedom nonlinear system with stochastic harmonic excitation and colored Gaussian noise. The stationary probability density function(PDF) of the system is derived through a probabilistic decomposition-synthesis method. Based on this, we infer the classical damage rate of the system. Furthermore, a new indicator, independent of the PDF, is proposed to quantify the damage related only to the fourth-order moment of the system and the threshold for extreme events. It is more universal and easier to determine as compared with the classical damage rate. A large damping ratio, a large noise intensity, or a short correlation time can reduce the damage rate and the value of the indicator.These findings provide new insights and theoretical guidance to avoid extreme oscillations and assess the reliability of practical ship movements.展开更多
基金Guangdong Major Project of Basic and Applied Basic Research (2020B0301030004)National Natural Science Foundation of China (42275020)+1 种基金Innovation Group Project of Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai) (311021001)Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies (2020B1212060025)。
文摘Concurrent extreme weather events in geographically distant areas potentially cause high-end risks for societies.By using network analysis,the present study managed to identify significant nearly-simultaneous occurrences of heatwaves between the grid cells in East Asia and Eastern Europe,even though they are geographically far away from each other.By further composite analysis,this study revealed that hot events first occurred in Eastern Europe,typically with a time lag of3-4 days before the East Asian heatwave events.An eastward propagating atmospheric wave train,known as the circumglobal teleconnection(CGT)pattern,bridged the sequent occurrences of extreme events in these two remote regions.Atmospheric blockings,amplified by surface warming over Eastern Europe,not only enhanced local heat extremes but also excited a CGT-like pattern characterized by alternative anomalies of high and low pressures.Subsequent downstream anticyclones in the middle and upper troposphere reduced local cloud cover and increased downward solar radiation,thereby facilitating the formation of heatwaves over East Asia.Nearly half of East Asian heatwave events were preceded by Eastern European heatwave events in the 10-day time range before East Asian heatwave events.This investigation of heatwave teleconnection in the two distant regions exhibits strong potential to improve the prediction accuracy of East Asian heatwaves.
基金We thank research center“Symbiosis”and immunochemistry laboratory IBPPM RAS for their support with immunofuorescence analysis and confocal microscopy within Project No.GR 121031100266-3SGO,FI,SA,BI,TA,DA,ZM,ED,AV,EA,VV,TA,KV,MM,and MA were supported by grant(No.23-75-30001)+1 种基金the Russian Science Foundation,DA and ED were supported by Grant(No.21-75-10088)the Russian Science Foundation and by Grant from the Russian Ministry of Science and High Education(No.075-15-2022-1094).
文摘With the increase in the aging population,the global number of people with Alzheimer’s disease(AD)progressively increased worldwide.The situation is aggravated by the fact that there is no the efective pharmacological therapy of AD.Photobiomodulation(PBM)is non-pharmacological approach that has shown very promising results in the therapy of AD in pilot clinical and animal studies.However,the mechanisms of therapeutic efects of PBM for AD are poorly understood.In this study on mice,we demonstrate that photodynamic efects of 5-aminolevulenic acid and laser 635 nm cause reduction of network of the meningeal lymphatic vessels(MLVs)leading to suppression of lymphatic removal of beta-amyloid(Aβ)from the right lateral ventricle and the hippocampus.Using the original protocol of PBM under electroencephalographic monitoring of wakefulness and sleep stages in non-anesthetized mice,we discover that the 7-day course of PBM during deep sleep vs.wakefulness provides better restoration of clearance of Aβfrom the ventricular system of the brain and the hippocampus.Our results shed light on the mechanism of PBM and show the stimulating efects of PBM on the brain lymphatic drainage that promotes transport of Aβvia the lymphatic pathway.The efects of PBM on the brain lymphatics in sleeping brain open a new niche in the study of restorative functions of sleep as well as it is an important informative platform for the development of innovative smart sleep technologies for the therapy of AD.
基金supported by the National Natural Science Foundation of China(Grant No.12072264)the Key International(Regional) Joint Research Program of the National Natural Science Foundation of China(Grant No.12120101002)+2 种基金the support of the National Natural Science Foundation of China(Grant No.12272296)the Natural Science Foundation of Chongqing,China(Grant No.cstc2021jcyj-msxmX0738)the Natural Science Foundation of Guangdong Province,China(Grant No.2023A1515012329)。
文摘Large-amplitude rolling motions, also regarded as extreme oscillations, are a great threat to marine navigation, which may lead to capsizing in ship motion. Therefore, it is important to quantify extreme oscillations, assess reliability of ship systems, and establish a suitable indicator to characterize extreme oscillations in ship systems. In this work, extreme events are investigated in a ship model considering a complex ocean environment, described by a single-degree-of-freedom nonlinear system with stochastic harmonic excitation and colored Gaussian noise. The stationary probability density function(PDF) of the system is derived through a probabilistic decomposition-synthesis method. Based on this, we infer the classical damage rate of the system. Furthermore, a new indicator, independent of the PDF, is proposed to quantify the damage related only to the fourth-order moment of the system and the threshold for extreme events. It is more universal and easier to determine as compared with the classical damage rate. A large damping ratio, a large noise intensity, or a short correlation time can reduce the damage rate and the value of the indicator.These findings provide new insights and theoretical guidance to avoid extreme oscillations and assess the reliability of practical ship movements.
