Based on the lightning observation data from the Fengyun-4A(FY-4A)Lightning Mapping Imager(FY-4A/LMI)and the Lightning Imaging Sensor(LIS)on the International Space Station(ISS),we extract the“event”type data as the...Based on the lightning observation data from the Fengyun-4A(FY-4A)Lightning Mapping Imager(FY-4A/LMI)and the Lightning Imaging Sensor(LIS)on the International Space Station(ISS),we extract the“event”type data as the lightning detection results.These observations are then compared with the cloud-to-ground(CG)lightning observation data from the China Meteorological Administration.This study focuses on the characteristics of lightning activity in Southeast China,primarily in Jiangxi Province and its adjacent areas,from April to September,2017–2022.In addition,with the fifth-generation European Centre for Medium-Range Weather Forecasts reanalysis data,we further delved into the potential factors influencing the distribution and variations in lightning activity and their primary related factors.Our findings indicate that the lightning frequency and density of the FY-4A/LMI,ISS-LIS and CG data are higher in southern and central Jiangxi,central Fujian Province,and western and central Guangdong Province,while they tend to be lower in eastern Hunan Province.In general,the high-value areas of lightning density for the FY-4A/LMI are located in inland mountainous areas.The lower the latitude is,the higher the CG lightning density is.High-value areas of the CG lightning density are more likely to be located in eastern Fujian and southeastern Zhejiang Province.However,the high-value areas of lightning density for the ISS-LIS are more dispersed,with a scattered distribution in inland mountainous areas and along the coast of eastern Fujian.Thus,the mountainous terrain is closely related to the high-value areas of the lightning density.The locations of the high-value areas of the lightning density for the FY-4A/LMI correspond well with those for the CG observations,and the seasonal variations are also consistent.In contrast,the distribution of the high-value areas of the lightning density for the ISS-LIS is more dispersed.The positions of the peak frequency of the FY-4A/LMI lightning and CG lightning contrast with local altitudes,primarily located at lower altitudes or near mountainsides.K-index and convective available potential energy(CAPE)can better reflect the local boundary layer conditions,where the lightning density is higher and lightning seasonal variations are apparent.There are strong correlations in the annual variations between the dew-point temperature(Td)and CG lightning frequency,and the monthly variations of the dew-point temperature and CAPE are also strongly correlated with monthly variations of CG lightning,while they are weakly correlated with the lightning frequency for the FY-4A/LMI and ISS-LIS.This result reflects that the CAPE shows a remarkable effect on the CG lightning frequency during seasonal transitions.展开更多
As of March 1,Malaysia,Singapore,and Thailand have all implemented visa-free entry policy for Chinese citizens,allowing stays of up to 30 days.The three Southeast Asian countries have been popular destinations for Chi...As of March 1,Malaysia,Singapore,and Thailand have all implemented visa-free entry policy for Chinese citizens,allowing stays of up to 30 days.The three Southeast Asian countries have been popular destinations for Chinese outbound tourists since the late 1980s and early 1990s.The implementation of the visa-free entry policy is expected to attract more Chinese tourists,especially young people,to travel to Southeast Asia and boost the recovery of the tourism industry in the region.展开更多
As we all know,Southeast Asia has become a hot destination for Chinese enterprises to invest in.The latest report shows that Southeast Asia continues to attract China’s capital,within which the medical industry has b...As we all know,Southeast Asia has become a hot destination for Chinese enterprises to invest in.The latest report shows that Southeast Asia continues to attract China’s capital,within which the medical industry has become an important area for Chinese enterprises to invest in,and the investment activity has gradually warmed up despite fluctuations.展开更多
Pinus is an economically and ecologically important genus whose members are dominant components globally in low-latitude mountainous and mid-latitude temperate forests.Pinus species richness is currently concentrated ...Pinus is an economically and ecologically important genus whose members are dominant components globally in low-latitude mountainous and mid-latitude temperate forests.Pinus species richness is currently concentrated in subtropical mid-low latitudes of the Northern Hemisphere,differing from the latitudinal diversity gradient mostly recognized in woody angiosperms.How the present pattern was developing in Earth's past is still poorly studied,particularly in eastern Asia.Here,a new fossil species,Pinus shengxianica sp.nov.is described based on a fossil seed cone from the Late Miocene Shengxian Formation in Zhejiang,southeast China.A co-occurring cone is recognized as a known fossil species,Pinus speciosa Li.Extensive comparison of extant and fossil members of Pinus suggests P.shengxianica shares a striking cone similarity to Pinus merkusii and Pinus latteri(subsection Pinus)from tropical Southeast Asia in having annular bulges around the umbo on the apophysis.The morphological resemblance indicates these two extant low-latitude pines probably possess a close affinity with the present newly-discovered P.shengxianica and originated from East Asian mid-low latitude ancestors during this generic re-diversification in the Miocene.This scenario is consistent with the evolutionary trajectory reflected by the pine fossil history and molecular data,marking the Miocene as a key period for the origin and evolution of most extant pines globally.The co-occurrences of diverse conifers and broadleaved angiosperms preferring diverse niches demonstrate Late Miocene eastern Zhejiang was one of the hot spots for coniferophyte diversity and hosted a needled-broadleaved mixed forest with complex vegetation structure and an altitudinal zonation.展开更多
Introduction: People in rural communities are exposed to the risk factors for non-communicable disease as those in urban areas. Correct interpretation and management of symptoms are important in primary care especiall...Introduction: People in rural communities are exposed to the risk factors for non-communicable disease as those in urban areas. Correct interpretation and management of symptoms are important in primary care especially in rural communities where diagnostic facilities are not readily available. Materials and Methods: This was a cross-sectional study carried out in a village in Enugu South Local Government area of Enugu State. Thorough medical history was taken from all eligible participants who gave their consent. Data were analyzed using SPSS version 26. Results: Data from a total of 1019 (64.7%) out of 1576 participants were analysed. Fever was by far the most common presenting complaint 580 (56.9%) of all participants and 67.9% of medical complaints seen in the clinic. This was followed remotely by musculoskeletal problems and neurological problems 15.6% and 3.8% of the participants respectively. Across all age groups, febrile illness was more than non-febrile illness except in those 65 years. Generalized body pains 74 (7.3%), back pains 55 (5.1), headache 33 (3.2%) and abdominal pains 24 (2.4%) were the commonest symptoms presented by the participants. About 15 (1.5%) of the population surveyed had had trauma/surgery in the past. This was twice the number who presented to the clinic with symptoms related to injury and trauma 7 (0.7%). Conclusions: Fever and musculoskeletal pains are the dominant medical complaints presented by adults in a rural community clinic. This may be related to the season of the year and the occupation of the population studied.展开更多
BACKGROUND Current approaches for the therapy of diabetic retinopathy(DR),which was one of leading causes of visual impairment,have their limitations.Animal experiments revealed that restructuring of intestinal microb...BACKGROUND Current approaches for the therapy of diabetic retinopathy(DR),which was one of leading causes of visual impairment,have their limitations.Animal experiments revealed that restructuring of intestinal microbiota can prevent retinopathy.AIM To explore the relationship between intestinal microbiota and DR among patients in the southeast coast of China,and provide clues for novel ways to prevention and treatment methods of DR.METHODS The fecal samples of non-diabetics(Group C,n=15)and diabetics(Group DM,n=30),including 15 samples with DR(Group DR)and 15 samples without DR(Group D),were analyzed by 16S rRNA sequencing.Intestinal microbiota compositions were compared between Group C and Group DM,Group DR and Group D,as well as patients with proliferative diabetic retinopathy(PDR)(Group PDR,n=8)and patients without PDR(Group NPDR,n=7).Spearman correlation analyses were performed to explore the associations between intestinal microbiota and clinical indicators.RESULTS The alpha and beta diversity did not differ significantly between Group DR and Group D as well as Group PDR and Group NPDR.At the family level,Fusobacteriaceae,Desulfovibrionaceae and Pseudomonadaceae were significantly increased in Group DR than in Group D(P<0.05,respectively).At the genera level,Fusobacterium,Pseudomonas,and Adlercreutzia were increased in Group DR than Group D while Senegalimassilia was decreased(P<0.05,respectively).Pseudomonas was negatively correlated with NK cell count(r=-0.39,P=0.03).Further,the abundance of genera Eubacterium(P<0.01),Peptococcus,Desulfovibrio,Acetanaerobacterium and Negativibacillus(P<0.05,respectively)were higher in Group PDR compared to Group NPDR,while Pseudomonas,Alloprevotella and Tyzzerella(P<0.05,respectively)were lower.Acetanaerobacterium and Desulfovibrio were positively correlated with fasting insulin(r=0.53 and 0.61,respectively,P<0.05),when Negativibacillus was negatively correlated with B cell count(r=-0.67,P<0.01).CONCLUSION Our findings indicated that the alteration of gut microbiota was associated with DR and its severity among patients in the southeast coast of China,probably by multiple mechanisms such as producing short-chain fatty acids,influencing permeability of blood vessels,affecting levels of vascular cell adhesion molecule-1,hypoxia-inducible factor-1,B cell and insulin.Modulating gut microbiota composition might be a novel strategy for prevention of DR,particularly PDR in population above.展开更多
In tropical countries,scorpion sting is a significant cause of disease,leading to severe localized cutaneous reactions,neurologic impairments,and respiratory distress,as well as myocarditis[1].The world’s most poison...In tropical countries,scorpion sting is a significant cause of disease,leading to severe localized cutaneous reactions,neurologic impairments,and respiratory distress,as well as myocarditis[1].The world’s most poisonous scorpion species,Leiurus quinquestriatus,is found in southern Turkey and is a threat to the public’s health in all of the provinces,particularly in Adiyaman and its surrounding areas,which were hit by the recent Turkey and Syria earthquake[1].展开更多
The fire-bellied newt genus Cynops contains ten known species distributed in China and Japan in East Asia.In this work,two new Cynops species are described,namely Cynops jiaoren sp.nov.distributed in northern Guangdon...The fire-bellied newt genus Cynops contains ten known species distributed in China and Japan in East Asia.In this work,two new Cynops species are described,namely Cynops jiaoren sp.nov.distributed in northern Guangdong and Cynops maguae sp.nov.distributed in eastern Jiangxi.The two new species can be distinctly distinguished from their congeners by the independent phylogenetic placements and a combination of morphological characteristics.The discovery of these two new species in the Southeast Chinese Hilly Area,where half of congeners occur,increases the known diversity of Cynops,and indicates unresolved relationships among the species in southeastern China.Further discussions on the taxonomic status of Cynops cyanurus are also provided.展开更多
Driven by geographical and encouraging policy factors,Chinese e-commerce enterprises have always regarded Southeast Asia as the first stop of taking their business overseas.Although the Indonesian subsidiary of JD.com...Driven by geographical and encouraging policy factors,Chinese e-commerce enterprises have always regarded Southeast Asia as the first stop of taking their business overseas.Although the Indonesian subsidiary of JD.com announced that it would stop services on March 31,and JD.com Thailand had announced that it would be closed,the Chinese e-commerce platform Alibaba,and cross-border e-commerce operation platform TikTok Shop,said they would continue to expand businesses in Southeast Asia.展开更多
Traditional Chinese medicine(TCM),a gem in the treasure trove of Chinese culture,offers crucial insights into the time-honored Oriental civilization.As early as the Qin Dynasty(221-206 BC),increased trade and cultural...Traditional Chinese medicine(TCM),a gem in the treasure trove of Chinese culture,offers crucial insights into the time-honored Oriental civilization.As early as the Qin Dynasty(221-206 BC),increased trade and cultural interactions between China and neighboring Southeast Asian countries had already brought the Chinese medical therapies to the region as optional treatments.展开更多
Multi-year SST and NCEP/NCAR reanalyzed wind data were employed to study the impacts of El Nio on the Southeast Asian summer monsoon (SEASM). It was found that the impacts of El Nio on the SEASM differed distinctly fr...Multi-year SST and NCEP/NCAR reanalyzed wind data were employed to study the impacts of El Nio on the Southeast Asian summer monsoon (SEASM). It was found that the impacts of El Nio on the SEASM differed distinctly from those on the East Asian summer monsoon (EASM) and the Indian summer monsoon (ISM). Composite analysis indicated that the "gear point" of coupling between the Indo-monsoon circulation and the Pacific-Walker circulation was located in the western margins of Southeast Asia when the developing stage of El Nio events covered the boreal summer. The anomalous circulations in the lower and upper troposphere and divergent circulation are all favorable for the strengthening of the SEASM during this period. Following the evolution of El Nio, the "gear point" of the two cells shifted eastward to the central Pacific when the mature or decaying period of El Nio events covered the boreal summer. The anomalous circulations are favorable for the weakening of the SEASM. The anomalous indexes of intensity of SEASM accord well with the above results. Additionally, the difference of SSTA patterns in the tropical Indo-Pacific Ocean between the two stages of the El Nio may play an important role.展开更多
In the Southeast Margin of the Tibetan Plateau, low-velocity sedimentary layers that would significantly affect the accuracy of the H-κ stacking of receiver functions are widely distributed.In this study, we use tele...In the Southeast Margin of the Tibetan Plateau, low-velocity sedimentary layers that would significantly affect the accuracy of the H-κ stacking of receiver functions are widely distributed.In this study, we use teleseismic waveform data of 475 events from 97 temporary broadband seismometers deployed by ChinArray Phase I to obtain crustal thicknesses and Poisson's ratios within the Chuxiong-Simao Basin and adjacent area, employing an improved method in which the receiver functions are processed through a resonance-removal filter, and the H-κ stacking is time-corrected.Results show that the crustal thickness ranges from 30 to 55 km in the study area, reaching its thickest value in the northwest and thinning toward southwest, southeast and northeast.The apparent variation of crustal thickness around the Red River Fault supports the view of southeastern escape of the Tibetan Plateau.Relatively thin crustal thickness in the zone between Chuxiong City and the Red River Fault indicates possible uplift of mantle in this area.The positive correlation between crustal thickness and Poisson's ratio is likely to be related to lower crust thickening.Comparison of results obtained from different methods shows that the improved method used in our study can effectively remove the reverberation effect of sedimentary layers.展开更多
There are many active faults in the southeast margin of Tibetan Plateau,where three large active faults zones,the Longmenshan,Xianshuihe and Anninghe,merge to form a"Y"shape.Strong crustal deformation and a ...There are many active faults in the southeast margin of Tibetan Plateau,where three large active faults zones,the Longmenshan,Xianshuihe and Anninghe,merge to form a"Y"shape.Strong crustal deformation and a complicated fault distribution accompany strong earthquake activity in this zone.In this paper,we investigate a multi-scale gravity anomaly in the southeastern margin of the Tibetan Plateau using the wavelet transform;we find that the pattern of the gravity field is closely related to the fault system in the study area.Analyzing the characteristics of this Bouguer gravity anomaly at different orders indicates that the eastern Himalayan syntaxis has produced a strong eastward push during its northward movement,resulting in a shortening of the crust from west to east and a rapid uplift of the Tibetan Plateau.The Songpan–Garzêand Sichuan–Yunnan blocks have been forced to slip and extrude southward and eastward laterally.The distributions of seven large earthquakes from 1970 to 2018 reflects the relationship between large earthquakes and characteristics of the gravity anomaly.Comparing the tectonic backgrounds of several earthquakes reveals that the large earthquakes occur usually in the high gravity anomaly gradient zone,which corresponds in general to the boundary zones of the blocks.We infer that large earthquakes occur primarily in high Bouguer gravity anomaly zones in the upper crust,while low Bouguer gravity anomalies encompass the lower crust and the uppermost mantle.展开更多
A quantitative approach to the national geopolitical influence is helpful to provide a reference for national sustainable development on the international stage, based on describing national diplomatic capacity and ov...A quantitative approach to the national geopolitical influence is helpful to provide a reference for national sustainable development on the international stage, based on describing national diplomatic capacity and overseas influence. Herein, this study proposes a complex geopolitical influence model, considering the affected nations' response. The geopolitical influences of great power in the affected nation are correlated with overall strength, the acceptance degree of the affected nation to the great power and the distance between both sides. Then, the geopolitical influences of China and the US in Southeast Asia countries are empirically analyzed from 2005 to 2015. The geopolitical influence of China in Southeast Asia has been largely growing for the past decades, accompanying with a constant trend of the US' effects. It is believed that China and the US can coexist peacefully in Southeast Asia to promote the regional development, and jointly create an open, inclusive and balanced regional cooperation architecture that benefits all nations in this region and great powers, through mutual political trust and economic beneficial cooperation. This study may contribute to advancing the policy debate and determining the optimal cooperation in pledging commitment to a new and sustainable model of great power relationship among the various regional geopolitical options.展开更多
The orogenic gold deposits in Southeast Guizhou are an important component of the Xuefeng polymetallic ore belt and have significant exploration potential, but geochronology research on these gold deposits is scarce. ...The orogenic gold deposits in Southeast Guizhou are an important component of the Xuefeng polymetallic ore belt and have significant exploration potential, but geochronology research on these gold deposits is scarce. Therefore, the ore genetic models are poorly constrained and remain unclear. In the present study, two important deposits(Pingqiu and Jinjing) are investigated, including combined Re-Os dating and the He-Ar isotope study of auriferous arsenopyrites. It is found that the arsenopyrites from the Pingqiu gold deposit yielded an isochron age of 400 ± 24 Ma,with an initial ^(187)Os/^(188)Os ratio of 1.24 ± 0.57(MSWD = 0.96). An identical isochron age of 400 ± 11 Ma with an initial ^(187)Os/^(188)Os ratio of 1.55 ± 0.14(MSWD = 0.34) was obtained from the Jinjing deposit. These ages correspond to the regional Caledonian orogeny and are interpreted to represent the age of the main stage ore. Both initial ^(187)Os ratios suggest that the Os was derived from crustal rocks. Combined with previous rare earth element(REE), trace elements, Nd-Sr-S-Pb isotope studies on scheelite, inclusion fluids with other residues of gangue quartz, and sulfides from other gold deposits in the region, it is suggested that the ore metals from Pingqiu and Jinjing were sourced from the Xiajiang Group. The He and Ar isotopes of arsenopyrites are characterized by ~3 He/~4 He ratios ranging from 5.3 × 10^(-4) Ra to 2.5 × 10^(-2) Ra(Ra = 1.4 × 10^(-6), the ~3 He/~4 He ratio of air), 40 Ar=/~4 He ratios from 0.64 × 10^(-2) to 15.39×10^(-2), and ^(40)Ar/^(36)Ar ratios from 633.2 to 6582.0. Those noble gas isotopic compositions of fluid inclusions also support a crustal source origin,evidenced by the Os isotope. Meanwhile, recent noble gas studies suggest that the amount of in situ radiogenic ~4 He generated should not be ignored, even when Th and U are present at levels of only a few ppm in host minerals.展开更多
To investigate genetic diversities among the AA genome Oryza species in the Southeast and South Asia, a total of 428 accessions of the AA genome Oryza species were genotyped using 36 simple sequence repeats (SSR) mark...To investigate genetic diversities among the AA genome Oryza species in the Southeast and South Asia, a total of 428 accessions of the AA genome Oryza species were genotyped using 36 simple sequence repeats (SSR) markers distributed throughout the rice genome. All of the 36 SSR markers generated polymorphic bands, revealing 100% polymorphism. The number of alleles per locus ranged from 3 to 17 with the mean of 8.6. The Nei's genetic diversity index (He) ranged from 0.337 at RM455 to 0.865 at RM169 with an average value of 0.650. The genetic diversity of the AA genome Oryza species in the Southeast Asia was obviously higher than that in the South Asia. Among the detected Oryza species in the South and Southeast Asia, O. rufipogon showed the highest genetic diversity. Meanwhile, a higher genetic differentiation (Fst) was found among the detected Oryza species in the Southeast Asia than in the South Asia. The Fst value between O. nivara and O. sativa was the highest. The results from the number of specific alleles, specific loci, and allele frequency confirmed the greater genetic variation among the detected species. In addition, the specific allele in RM161 displayed higher frequency (0.193), suggesting its important function in identifying Oryza species of AA genome.展开更多
Objective The Babu ophiolite in Malipo County of southeastern Yunnan is interpreted as remanant ocean crust and represents a possible branch of Paleo-Tethyan Ocean in South China.It consists mainly of mafic and ultram...Objective The Babu ophiolite in Malipo County of southeastern Yunnan is interpreted as remanant ocean crust and represents a possible branch of Paleo-Tethyan Ocean in South China.It consists mainly of mafic and ultramafic rocks.These rocks are very important to understand the evolution of the Paleo-Tethyan Ocean.However,the Babu ophiolite is still disputed and the mafic and ultramafic rocks have been inferred to be part of the Emeishan large igneous province(LIP)by some researchers.In this paper,we present zircon U-Pb data on the metabasalts in展开更多
The garnet amphibolites from the newly identified Wanhe ophiolitic mélange in the Changning-Menglian suture zone(CMSZ)provide a probe to elucidate the evolution of the Triassic Palaeo-Tethys.An integrated petrolo...The garnet amphibolites from the newly identified Wanhe ophiolitic mélange in the Changning-Menglian suture zone(CMSZ)provide a probe to elucidate the evolution of the Triassic Palaeo-Tethys.An integrated petrologic,phase equilibria modeling and geochronological study of the garnet amphibolites,southeast Tibetan Plateau,shows that the garnet amphibolites have a peak mineral assemblage of garnet,glaucophane,lawsonite,chlorite,rutile,phengite and quartz,and a clockwise P-T path with a prograde segment from blueschist-facies to eclogite-facies with a peak-metamorphic P-T conditions of 2000–2100 MPa and 495–515℃,indicating a cold geothermal gradient of about 240–260℃/GPa.Theretrograde metamorphic P-T path is characterized by nearly isothermal decompression to lower amphibolite-facies and subsequent cooling to greenschist-facies.The metamorphic zircons have fractionated HREE patterns and significant negative Eu anomalies,and therefore the obtained zircon U-Pb age of 231±1.5 Ma is interpreted to be the timing of the amphibolite facies metamorphism occurrence.The present study probably indicates that the garnet amphibolites in the Wanhe ophiolitic mélange was the retrograded highpressure eclogite-facies blueschist,instead of the previously proposed eclogites,and the garnet amphibolites recorded the subduction and exhumation process of the Palaeo-Tethys Oceanic crust in the Triassic.展开更多
Tropical mountainous areas not only provide substantial carbon storage and play an important role in global biological diversity, but also provide basic livelihood for a large number of poor ethnic minorities. However...Tropical mountainous areas not only provide substantial carbon storage and play an important role in global biological diversity, but also provide basic livelihood for a large number of poor ethnic minorities. However, there is no unified and explicit definition for mountainous areas. The local elevation range(LER) is a crucial structural parameter for delineating mountainous areas. However, current LER products are limited by the subjective selection of an optimum statistical window or coarser spatial resolution of topographical data. In this study, we presented an approach using thresholds for three topographic parameters, elevation, slope, and LER, derived from the Advanced Spaceborne Thermal Emission and Reflection Radiometer Global Digital Elevation Model(ASTER GDEM) to redelineate the vast mountainous areas of mainland Southeast Asia(MSEA). The mean change-point analysis method was applied to determine the optimum statistical window of the 1 arc second(approximately 30 m)-resolution GDEM LER. The results showed that: First, the optimum statistical window is 38 × 38 cell units(width × height) in a rectangular neighborhood, or an area of about 1.30 km^2 for calculating GDEM LER in MSEA. Second, the LER of more than 80% of the area ranges from 30 m to 499 m in MSEA. The LERs in the northern and northwestern MSEA are greater than their counterparts in the south and east. Third, the area of the re-delineated mountainous areas was 83.52 × 10~4 km^2, about 38.71% of the total area. Spatially, the mountainous areas are mainly distributed in the north and northeast of MSEA. The re-delineated 30-m resolution map of the mountainous areas will serve as a topographical dataset for monitoring mountainrelated land surface changes in MSEA. The parameter-modified mountain extraction procedure can be expanded to delineate global mountainous areas.展开更多
基金National Natural Science Foundation of China(42175014,42205137)Open Research Fund of Institute of Meteorological Technology Innovation,Nanjing(BJG202202)+3 种基金Joint Research Project of Typhoon Research,Shanghai Typhoon Institute,China Meteorological Administration(TFJJ202209)Innovation Development Project of China Meteorological Administration(CXFZ2023P001)Open Project of KLME&CIC-FEMD(KLME202311)Jiangxi MDIA-ASI Fund。
文摘Based on the lightning observation data from the Fengyun-4A(FY-4A)Lightning Mapping Imager(FY-4A/LMI)and the Lightning Imaging Sensor(LIS)on the International Space Station(ISS),we extract the“event”type data as the lightning detection results.These observations are then compared with the cloud-to-ground(CG)lightning observation data from the China Meteorological Administration.This study focuses on the characteristics of lightning activity in Southeast China,primarily in Jiangxi Province and its adjacent areas,from April to September,2017–2022.In addition,with the fifth-generation European Centre for Medium-Range Weather Forecasts reanalysis data,we further delved into the potential factors influencing the distribution and variations in lightning activity and their primary related factors.Our findings indicate that the lightning frequency and density of the FY-4A/LMI,ISS-LIS and CG data are higher in southern and central Jiangxi,central Fujian Province,and western and central Guangdong Province,while they tend to be lower in eastern Hunan Province.In general,the high-value areas of lightning density for the FY-4A/LMI are located in inland mountainous areas.The lower the latitude is,the higher the CG lightning density is.High-value areas of the CG lightning density are more likely to be located in eastern Fujian and southeastern Zhejiang Province.However,the high-value areas of lightning density for the ISS-LIS are more dispersed,with a scattered distribution in inland mountainous areas and along the coast of eastern Fujian.Thus,the mountainous terrain is closely related to the high-value areas of the lightning density.The locations of the high-value areas of the lightning density for the FY-4A/LMI correspond well with those for the CG observations,and the seasonal variations are also consistent.In contrast,the distribution of the high-value areas of the lightning density for the ISS-LIS is more dispersed.The positions of the peak frequency of the FY-4A/LMI lightning and CG lightning contrast with local altitudes,primarily located at lower altitudes or near mountainsides.K-index and convective available potential energy(CAPE)can better reflect the local boundary layer conditions,where the lightning density is higher and lightning seasonal variations are apparent.There are strong correlations in the annual variations between the dew-point temperature(Td)and CG lightning frequency,and the monthly variations of the dew-point temperature and CAPE are also strongly correlated with monthly variations of CG lightning,while they are weakly correlated with the lightning frequency for the FY-4A/LMI and ISS-LIS.This result reflects that the CAPE shows a remarkable effect on the CG lightning frequency during seasonal transitions.
文摘As of March 1,Malaysia,Singapore,and Thailand have all implemented visa-free entry policy for Chinese citizens,allowing stays of up to 30 days.The three Southeast Asian countries have been popular destinations for Chinese outbound tourists since the late 1980s and early 1990s.The implementation of the visa-free entry policy is expected to attract more Chinese tourists,especially young people,to travel to Southeast Asia and boost the recovery of the tourism industry in the region.
文摘As we all know,Southeast Asia has become a hot destination for Chinese enterprises to invest in.The latest report shows that Southeast Asia continues to attract China’s capital,within which the medical industry has become an important area for Chinese enterprises to invest in,and the investment activity has gradually warmed up despite fluctuations.
基金This work was funded in part by the National Natural Science Foundation of China(No.41872017)the Foundation of State Key Laboratory of Palaeobiology and Stratigraphy(Nanjing Institute of Geology and Palaeontology,CAS)(Nos.193113 and 183125)+1 种基金the Fundamental Research Funds for the Central Universities,CHD(Nos.300102272206,300102271402 and 300102271403)the Undergraduate Innovation and Entrepreneurship Project(No.S202210710194).
文摘Pinus is an economically and ecologically important genus whose members are dominant components globally in low-latitude mountainous and mid-latitude temperate forests.Pinus species richness is currently concentrated in subtropical mid-low latitudes of the Northern Hemisphere,differing from the latitudinal diversity gradient mostly recognized in woody angiosperms.How the present pattern was developing in Earth's past is still poorly studied,particularly in eastern Asia.Here,a new fossil species,Pinus shengxianica sp.nov.is described based on a fossil seed cone from the Late Miocene Shengxian Formation in Zhejiang,southeast China.A co-occurring cone is recognized as a known fossil species,Pinus speciosa Li.Extensive comparison of extant and fossil members of Pinus suggests P.shengxianica shares a striking cone similarity to Pinus merkusii and Pinus latteri(subsection Pinus)from tropical Southeast Asia in having annular bulges around the umbo on the apophysis.The morphological resemblance indicates these two extant low-latitude pines probably possess a close affinity with the present newly-discovered P.shengxianica and originated from East Asian mid-low latitude ancestors during this generic re-diversification in the Miocene.This scenario is consistent with the evolutionary trajectory reflected by the pine fossil history and molecular data,marking the Miocene as a key period for the origin and evolution of most extant pines globally.The co-occurrences of diverse conifers and broadleaved angiosperms preferring diverse niches demonstrate Late Miocene eastern Zhejiang was one of the hot spots for coniferophyte diversity and hosted a needled-broadleaved mixed forest with complex vegetation structure and an altitudinal zonation.
文摘Introduction: People in rural communities are exposed to the risk factors for non-communicable disease as those in urban areas. Correct interpretation and management of symptoms are important in primary care especially in rural communities where diagnostic facilities are not readily available. Materials and Methods: This was a cross-sectional study carried out in a village in Enugu South Local Government area of Enugu State. Thorough medical history was taken from all eligible participants who gave their consent. Data were analyzed using SPSS version 26. Results: Data from a total of 1019 (64.7%) out of 1576 participants were analysed. Fever was by far the most common presenting complaint 580 (56.9%) of all participants and 67.9% of medical complaints seen in the clinic. This was followed remotely by musculoskeletal problems and neurological problems 15.6% and 3.8% of the participants respectively. Across all age groups, febrile illness was more than non-febrile illness except in those 65 years. Generalized body pains 74 (7.3%), back pains 55 (5.1), headache 33 (3.2%) and abdominal pains 24 (2.4%) were the commonest symptoms presented by the participants. About 15 (1.5%) of the population surveyed had had trauma/surgery in the past. This was twice the number who presented to the clinic with symptoms related to injury and trauma 7 (0.7%). Conclusions: Fever and musculoskeletal pains are the dominant medical complaints presented by adults in a rural community clinic. This may be related to the season of the year and the occupation of the population studied.
基金Supported by Wenzhou Science and Technology Bureau,No.Y20190129 and No.Y2020263.
文摘BACKGROUND Current approaches for the therapy of diabetic retinopathy(DR),which was one of leading causes of visual impairment,have their limitations.Animal experiments revealed that restructuring of intestinal microbiota can prevent retinopathy.AIM To explore the relationship between intestinal microbiota and DR among patients in the southeast coast of China,and provide clues for novel ways to prevention and treatment methods of DR.METHODS The fecal samples of non-diabetics(Group C,n=15)and diabetics(Group DM,n=30),including 15 samples with DR(Group DR)and 15 samples without DR(Group D),were analyzed by 16S rRNA sequencing.Intestinal microbiota compositions were compared between Group C and Group DM,Group DR and Group D,as well as patients with proliferative diabetic retinopathy(PDR)(Group PDR,n=8)and patients without PDR(Group NPDR,n=7).Spearman correlation analyses were performed to explore the associations between intestinal microbiota and clinical indicators.RESULTS The alpha and beta diversity did not differ significantly between Group DR and Group D as well as Group PDR and Group NPDR.At the family level,Fusobacteriaceae,Desulfovibrionaceae and Pseudomonadaceae were significantly increased in Group DR than in Group D(P<0.05,respectively).At the genera level,Fusobacterium,Pseudomonas,and Adlercreutzia were increased in Group DR than Group D while Senegalimassilia was decreased(P<0.05,respectively).Pseudomonas was negatively correlated with NK cell count(r=-0.39,P=0.03).Further,the abundance of genera Eubacterium(P<0.01),Peptococcus,Desulfovibrio,Acetanaerobacterium and Negativibacillus(P<0.05,respectively)were higher in Group PDR compared to Group NPDR,while Pseudomonas,Alloprevotella and Tyzzerella(P<0.05,respectively)were lower.Acetanaerobacterium and Desulfovibrio were positively correlated with fasting insulin(r=0.53 and 0.61,respectively,P<0.05),when Negativibacillus was negatively correlated with B cell count(r=-0.67,P<0.01).CONCLUSION Our findings indicated that the alteration of gut microbiota was associated with DR and its severity among patients in the southeast coast of China,probably by multiple mechanisms such as producing short-chain fatty acids,influencing permeability of blood vessels,affecting levels of vascular cell adhesion molecule-1,hypoxia-inducible factor-1,B cell and insulin.Modulating gut microbiota composition might be a novel strategy for prevention of DR,particularly PDR in population above.
文摘In tropical countries,scorpion sting is a significant cause of disease,leading to severe localized cutaneous reactions,neurologic impairments,and respiratory distress,as well as myocarditis[1].The world’s most poisonous scorpion species,Leiurus quinquestriatus,is found in southern Turkey and is a threat to the public’s health in all of the provinces,particularly in Adiyaman and its surrounding areas,which were hit by the recent Turkey and Syria earthquake[1].
基金supported by DFGP Project of Fauna of Guangdong-202115Nanling National Park Construction Project(No.ZD22-ZC016AG)+1 种基金2022 Wildlife Monitoring Projects of the Guangdong Forestry Bureauthe National Animal Collection Resource Center,China。
文摘The fire-bellied newt genus Cynops contains ten known species distributed in China and Japan in East Asia.In this work,two new Cynops species are described,namely Cynops jiaoren sp.nov.distributed in northern Guangdong and Cynops maguae sp.nov.distributed in eastern Jiangxi.The two new species can be distinctly distinguished from their congeners by the independent phylogenetic placements and a combination of morphological characteristics.The discovery of these two new species in the Southeast Chinese Hilly Area,where half of congeners occur,increases the known diversity of Cynops,and indicates unresolved relationships among the species in southeastern China.Further discussions on the taxonomic status of Cynops cyanurus are also provided.
文摘Driven by geographical and encouraging policy factors,Chinese e-commerce enterprises have always regarded Southeast Asia as the first stop of taking their business overseas.Although the Indonesian subsidiary of JD.com announced that it would stop services on March 31,and JD.com Thailand had announced that it would be closed,the Chinese e-commerce platform Alibaba,and cross-border e-commerce operation platform TikTok Shop,said they would continue to expand businesses in Southeast Asia.
文摘Traditional Chinese medicine(TCM),a gem in the treasure trove of Chinese culture,offers crucial insights into the time-honored Oriental civilization.As early as the Qin Dynasty(221-206 BC),increased trade and cultural interactions between China and neighboring Southeast Asian countries had already brought the Chinese medical therapies to the region as optional treatments.
基金Project KZCX2-205,G1998040900,Project of Natural Sciences foundation of Shandong Province"A study on the relationship between variability of warm pool and summer rainfall in Shandong"Key project of CAS"Integrated Study on the Activity of the SCS Monsoon and its Effects?"
文摘Multi-year SST and NCEP/NCAR reanalyzed wind data were employed to study the impacts of El Nio on the Southeast Asian summer monsoon (SEASM). It was found that the impacts of El Nio on the SEASM differed distinctly from those on the East Asian summer monsoon (EASM) and the Indian summer monsoon (ISM). Composite analysis indicated that the "gear point" of coupling between the Indo-monsoon circulation and the Pacific-Walker circulation was located in the western margins of Southeast Asia when the developing stage of El Nio events covered the boreal summer. The anomalous circulations in the lower and upper troposphere and divergent circulation are all favorable for the strengthening of the SEASM during this period. Following the evolution of El Nio, the "gear point" of the two cells shifted eastward to the central Pacific when the mature or decaying period of El Nio events covered the boreal summer. The anomalous circulations are favorable for the weakening of the SEASM. The anomalous indexes of intensity of SEASM accord well with the above results. Additionally, the difference of SSTA patterns in the tropical Indo-Pacific Ocean between the two stages of the El Nio may play an important role.
基金supported by the National Natural Science Foundation of China (Project 41730212)the Basic Research Project of the Institute of Earthquake Forecasting, China Earthquake Administration (2017IES0102)
文摘In the Southeast Margin of the Tibetan Plateau, low-velocity sedimentary layers that would significantly affect the accuracy of the H-κ stacking of receiver functions are widely distributed.In this study, we use teleseismic waveform data of 475 events from 97 temporary broadband seismometers deployed by ChinArray Phase I to obtain crustal thicknesses and Poisson's ratios within the Chuxiong-Simao Basin and adjacent area, employing an improved method in which the receiver functions are processed through a resonance-removal filter, and the H-κ stacking is time-corrected.Results show that the crustal thickness ranges from 30 to 55 km in the study area, reaching its thickest value in the northwest and thinning toward southwest, southeast and northeast.The apparent variation of crustal thickness around the Red River Fault supports the view of southeastern escape of the Tibetan Plateau.Relatively thin crustal thickness in the zone between Chuxiong City and the Red River Fault indicates possible uplift of mantle in this area.The positive correlation between crustal thickness and Poisson's ratio is likely to be related to lower crust thickening.Comparison of results obtained from different methods shows that the improved method used in our study can effectively remove the reverberation effect of sedimentary layers.
基金supported by the National Natural Science Foundation of China(Project 41730212)the Basic Research Project of the Institute of Earthquake Forecasting,China Earthquake Adm inistration(Grant No.2017IES0102)
文摘There are many active faults in the southeast margin of Tibetan Plateau,where three large active faults zones,the Longmenshan,Xianshuihe and Anninghe,merge to form a"Y"shape.Strong crustal deformation and a complicated fault distribution accompany strong earthquake activity in this zone.In this paper,we investigate a multi-scale gravity anomaly in the southeastern margin of the Tibetan Plateau using the wavelet transform;we find that the pattern of the gravity field is closely related to the fault system in the study area.Analyzing the characteristics of this Bouguer gravity anomaly at different orders indicates that the eastern Himalayan syntaxis has produced a strong eastward push during its northward movement,resulting in a shortening of the crust from west to east and a rapid uplift of the Tibetan Plateau.The Songpan–Garzêand Sichuan–Yunnan blocks have been forced to slip and extrude southward and eastward laterally.The distributions of seven large earthquakes from 1970 to 2018 reflects the relationship between large earthquakes and characteristics of the gravity anomaly.Comparing the tectonic backgrounds of several earthquakes reveals that the large earthquakes occur usually in the high gravity anomaly gradient zone,which corresponds in general to the boundary zones of the blocks.We infer that large earthquakes occur primarily in high Bouguer gravity anomaly zones in the upper crust,while low Bouguer gravity anomalies encompass the lower crust and the uppermost mantle.
基金Under the auspices of the Special Research Fund of China-ASEAN Collaborative Innovation Center for Regional Development and Development Program of Ministry of Education for Changjiang Scholars and Innovative Teams(No.CW201501)
文摘A quantitative approach to the national geopolitical influence is helpful to provide a reference for national sustainable development on the international stage, based on describing national diplomatic capacity and overseas influence. Herein, this study proposes a complex geopolitical influence model, considering the affected nations' response. The geopolitical influences of great power in the affected nation are correlated with overall strength, the acceptance degree of the affected nation to the great power and the distance between both sides. Then, the geopolitical influences of China and the US in Southeast Asia countries are empirically analyzed from 2005 to 2015. The geopolitical influence of China in Southeast Asia has been largely growing for the past decades, accompanying with a constant trend of the US' effects. It is believed that China and the US can coexist peacefully in Southeast Asia to promote the regional development, and jointly create an open, inclusive and balanced regional cooperation architecture that benefits all nations in this region and great powers, through mutual political trust and economic beneficial cooperation. This study may contribute to advancing the policy debate and determining the optimal cooperation in pledging commitment to a new and sustainable model of great power relationship among the various regional geopolitical options.
基金jointly supported by the National Natural Science Foundation of China (Grant Nos. 41303038, 41772070)Open Fund of State Key Laboratory of Ore Deposit Geochemistry (201502)the National Basic Research Program of China (2014CB440904)
文摘The orogenic gold deposits in Southeast Guizhou are an important component of the Xuefeng polymetallic ore belt and have significant exploration potential, but geochronology research on these gold deposits is scarce. Therefore, the ore genetic models are poorly constrained and remain unclear. In the present study, two important deposits(Pingqiu and Jinjing) are investigated, including combined Re-Os dating and the He-Ar isotope study of auriferous arsenopyrites. It is found that the arsenopyrites from the Pingqiu gold deposit yielded an isochron age of 400 ± 24 Ma,with an initial ^(187)Os/^(188)Os ratio of 1.24 ± 0.57(MSWD = 0.96). An identical isochron age of 400 ± 11 Ma with an initial ^(187)Os/^(188)Os ratio of 1.55 ± 0.14(MSWD = 0.34) was obtained from the Jinjing deposit. These ages correspond to the regional Caledonian orogeny and are interpreted to represent the age of the main stage ore. Both initial ^(187)Os ratios suggest that the Os was derived from crustal rocks. Combined with previous rare earth element(REE), trace elements, Nd-Sr-S-Pb isotope studies on scheelite, inclusion fluids with other residues of gangue quartz, and sulfides from other gold deposits in the region, it is suggested that the ore metals from Pingqiu and Jinjing were sourced from the Xiajiang Group. The He and Ar isotopes of arsenopyrites are characterized by ~3 He/~4 He ratios ranging from 5.3 × 10^(-4) Ra to 2.5 × 10^(-2) Ra(Ra = 1.4 × 10^(-6), the ~3 He/~4 He ratio of air), 40 Ar=/~4 He ratios from 0.64 × 10^(-2) to 15.39×10^(-2), and ^(40)Ar/^(36)Ar ratios from 633.2 to 6582.0. Those noble gas isotopic compositions of fluid inclusions also support a crustal source origin,evidenced by the Os isotope. Meanwhile, recent noble gas studies suggest that the amount of in situ radiogenic ~4 He generated should not be ignored, even when Th and U are present at levels of only a few ppm in host minerals.
基金supported by the National Basic Research Program of China (Grant No. 2004CB117201)the Basic Research Budget of the China National Rice Research Institute (Grant No. 100006)the Project of Agricultural Wild Plant Conservation of Ministry of Agriculture, China.
文摘To investigate genetic diversities among the AA genome Oryza species in the Southeast and South Asia, a total of 428 accessions of the AA genome Oryza species were genotyped using 36 simple sequence repeats (SSR) markers distributed throughout the rice genome. All of the 36 SSR markers generated polymorphic bands, revealing 100% polymorphism. The number of alleles per locus ranged from 3 to 17 with the mean of 8.6. The Nei's genetic diversity index (He) ranged from 0.337 at RM455 to 0.865 at RM169 with an average value of 0.650. The genetic diversity of the AA genome Oryza species in the Southeast Asia was obviously higher than that in the South Asia. Among the detected Oryza species in the South and Southeast Asia, O. rufipogon showed the highest genetic diversity. Meanwhile, a higher genetic differentiation (Fst) was found among the detected Oryza species in the Southeast Asia than in the South Asia. The Fst value between O. nivara and O. sativa was the highest. The results from the number of specific alleles, specific loci, and allele frequency confirmed the greater genetic variation among the detected species. In addition, the specific allele in RM161 displayed higher frequency (0.193), suggesting its important function in identifying Oryza species of AA genome.
基金supported by the National Natural Science Foundation of China(grant No.41502109)the 973 Program(grant No.2015CB453000)the China Postdoctoral Science Foundation(grant No. 2015M582528)
文摘Objective The Babu ophiolite in Malipo County of southeastern Yunnan is interpreted as remanant ocean crust and represents a possible branch of Paleo-Tethyan Ocean in South China.It consists mainly of mafic and ultramafic rocks.These rocks are very important to understand the evolution of the Paleo-Tethyan Ocean.However,the Babu ophiolite is still disputed and the mafic and ultramafic rocks have been inferred to be part of the Emeishan large igneous province(LIP)by some researchers.In this paper,we present zircon U-Pb data on the metabasalts in
基金supported by the National Natural Science Foundation of China(41802071,41773026 and 41303028)the Geological Survey of China-Nepal railway(202008000000180117).
文摘The garnet amphibolites from the newly identified Wanhe ophiolitic mélange in the Changning-Menglian suture zone(CMSZ)provide a probe to elucidate the evolution of the Triassic Palaeo-Tethys.An integrated petrologic,phase equilibria modeling and geochronological study of the garnet amphibolites,southeast Tibetan Plateau,shows that the garnet amphibolites have a peak mineral assemblage of garnet,glaucophane,lawsonite,chlorite,rutile,phengite and quartz,and a clockwise P-T path with a prograde segment from blueschist-facies to eclogite-facies with a peak-metamorphic P-T conditions of 2000–2100 MPa and 495–515℃,indicating a cold geothermal gradient of about 240–260℃/GPa.Theretrograde metamorphic P-T path is characterized by nearly isothermal decompression to lower amphibolite-facies and subsequent cooling to greenschist-facies.The metamorphic zircons have fractionated HREE patterns and significant negative Eu anomalies,and therefore the obtained zircon U-Pb age of 231±1.5 Ma is interpreted to be the timing of the amphibolite facies metamorphism occurrence.The present study probably indicates that the garnet amphibolites in the Wanhe ophiolitic mélange was the retrograded highpressure eclogite-facies blueschist,instead of the previously proposed eclogites,and the garnet amphibolites recorded the subduction and exhumation process of the Palaeo-Tethys Oceanic crust in the Triassic.
基金supported by the Strategic Priority Research Program of Chinese Academy of Sciences (Grant No. XDA20010203)
文摘Tropical mountainous areas not only provide substantial carbon storage and play an important role in global biological diversity, but also provide basic livelihood for a large number of poor ethnic minorities. However, there is no unified and explicit definition for mountainous areas. The local elevation range(LER) is a crucial structural parameter for delineating mountainous areas. However, current LER products are limited by the subjective selection of an optimum statistical window or coarser spatial resolution of topographical data. In this study, we presented an approach using thresholds for three topographic parameters, elevation, slope, and LER, derived from the Advanced Spaceborne Thermal Emission and Reflection Radiometer Global Digital Elevation Model(ASTER GDEM) to redelineate the vast mountainous areas of mainland Southeast Asia(MSEA). The mean change-point analysis method was applied to determine the optimum statistical window of the 1 arc second(approximately 30 m)-resolution GDEM LER. The results showed that: First, the optimum statistical window is 38 × 38 cell units(width × height) in a rectangular neighborhood, or an area of about 1.30 km^2 for calculating GDEM LER in MSEA. Second, the LER of more than 80% of the area ranges from 30 m to 499 m in MSEA. The LERs in the northern and northwestern MSEA are greater than their counterparts in the south and east. Third, the area of the re-delineated mountainous areas was 83.52 × 10~4 km^2, about 38.71% of the total area. Spatially, the mountainous areas are mainly distributed in the north and northeast of MSEA. The re-delineated 30-m resolution map of the mountainous areas will serve as a topographical dataset for monitoring mountainrelated land surface changes in MSEA. The parameter-modified mountain extraction procedure can be expanded to delineate global mountainous areas.
