On the tranquil waters of Xiaoshanyang,a small lake in Deqing County,Zhejiang Province,rows of white,spherical buoys are lined up in perfect order,resembling strands of pearl necklaces.Once a thousand-year-old pearl-f...On the tranquil waters of Xiaoshanyang,a small lake in Deqing County,Zhejiang Province,rows of white,spherical buoys are lined up in perfect order,resembling strands of pearl necklaces.Once a thousand-year-old pearl-farming site,this heritage-rich waterbody has emerged as a global benchmark for the preservation of agricultural heritage.展开更多
Clarifying the mechanisms that control the evolution of territorial space patterns is essential for regulating and optimizing the geographical structure and processes related to sustainable development.Using the Guang...Clarifying the mechanisms that control the evolution of territorial space patterns is essential for regulating and optimizing the geographical structure and processes related to sustainable development.Using the Guangdong and Guangxi sections of the Pearl River Basin as examples,the transfer-matrix method and standard deviation ellipse model were applied to characterize the evolution of territorial space patterns from 1990 to 2020.A trend surface analysis and the Theil index were used to analyze regional differences in the evolution process,and geodetectors were used to identify the underlying mechanisms of the changes.There were three key results.(1)In these critical areas of the Pearl River Basin,agricultural and ecological spaces have rapidly declined due to urban expansion,with transfers between these spaces dominating the evolution of territorial space patterns.Spatial pattern changes in the Guangdong section were more intense than in the Guangxi section.(2)Regional differences in urban space have decreased,whereas differences in agricultural and ecological spaces have intensified.Driven by socio-economic growth,the cross-regional transfers of territorial space have created a“high in the east,while low in the west”inter-regional difference,and a“high in the south,while low in the north”intra-regional difference shaped by natural conditions.The regional differences in space patterns were greater in Guangdong than in Guangxi.(3)The evolution of watershed territorial space patterns resulted from scale changes,locational shifts,structural reorganizations,and directional changes driven by multiple factors.Natural environment,social life,economic development,and policy factors played foundational,leading,key driving,and guiding roles,respectively.Additionally,the regional differences in the evolution of watershed territorial space patterns originated from the differential transmission of the influence of various factors affecting spatial evolution.Enhancing urban space efficiency,restructuring agricultural space,and optimizing ecological space are key strategies for building a complementary and synergistic territorial space pattern in the basin.展开更多
Based on the comprehensive analysis of data from petrology and mineralogy,well logging,seismic surveys,paleontology,and geochemistry,a detailed research was conducted on paleoenvironmental and paleoclimatic conditions...Based on the comprehensive analysis of data from petrology and mineralogy,well logging,seismic surveys,paleontology,and geochemistry,a detailed research was conducted on paleoenvironmental and paleoclimatic conditions,and modeling of the source rocks in the second member of the Eocene Wenchang Formation(Wen 2 Member)in the Northern Shunde Subsag at the southwestern margin of the Pearl River Mouth Basin.The Wen 2 Member hosts excellent,thick lacustrine source rocks with strong longitudinal heterogeneity and an average total organic carbon(TOC)content of over 4.9%.The Wen 2 Member can be divided into three units(I,II,III)from bottom to top.Unit I features excellent source rocks with Type I organic matters(average TOC of 5.9%)primarily sourced from lake organisms;Unit II hosts source rocks dominated by Type II2 organic matters(average TOC of 2.2%),which are originated from mixed sources dominated by terrestrial input.Unit III contains good to excellent source rocks dominated by Type II1 organic matters(average TOC of 4.9%),which are mainly contributed by lake organisms and partially by terrestrial input.Under the background of rapid subsidence and limited source supply during intense rifting period in the Eocene,excellent source rocks were developed in Wen 2 Member in the Northern Shunde Subsag under the coordinated control of warm and humid climate,volcanic activity,and deep-water reducing conditions.During the deposition of Unit I,the warm and humid climate and volcanic activity promoted the proliferation of lake algaes,primarily Granodiscus,resulting in high initial productivity,and deep-water reducing conditions enabled satisfactory preservation of organic matters.These factors jointly controlled the development and occurrence of excellent source rocks.During the deposition of Unit II,a transition from warm to cool and semi-arid paleoclimatic conditions led to a decrease in lake algaes and initial productivity.Additionally,enhanced terrestrial input and shallow-water,weakly oxidizing water conditions caused a significant dilution and decomposition of organic matters,degrading the quality of source rocks.During the deposition of Unit III,when the paleoclimatic conditions are cool and humid,Pediastrum and Botryococcus began to thrive,leading to an increase in productivity.Meanwhile,the reducing environment of semi-deep water facilitated the preservation of excellent source rocks,albeit slightly inferior to those in Unit I.The study results clarify the differential origins and development models of various source rocks in the Shunde Sag,offering valuable guidance for evaluating source rocks and selecting petroleum exploration targets in similar marginal sags.展开更多
Small RNAs(sRNAs)are a class of molecules capable of perceiving environmental changes and exerting posttranscriptional regulation over target gene expression,thereby influencing bacterial virulence and host immune res...Small RNAs(sRNAs)are a class of molecules capable of perceiving environmental changes and exerting posttranscriptional regulation over target gene expression,thereby influencing bacterial virulence and host immune responses.Pseudomonas plecoglossicida is a pathogenic bacterium that poses a significant threat to aquatic animal health.However,the regulatory mechanisms of sRNAs in P.plecoglossicida remain unclear.This study focused on sRNA113,previously identified as a potential regulator of the fliP gene,a key component of the lateral flagellar type III secretion system.To investigate the effects of sRNA113on P.plecoglossicida virulence,as well as its role in regulating pathogenic processes and host immune responses,mutant strains lacking this sRNA were generated and analyzed.Deletion of sRNA113 resulted in the up-regulation of lateral flagellar type III secretion system-related genes in P.plecoglossicida,which enhanced bacterial swarming motility,biofilm formation,and chemotaxis ability in vitro.In vivo infection experiments with pearl gentian grouper revealed that sRNA113 deletion enhanced the pathogenicity of P.plecoglossicida.This heightened virulence was attributed to the up-regulation of genes associated with the lateral flagellar type III secretion system,resulting in higher bacterial loads within host tissues.This amplification of pathogenic activity intensified tissue damage,disrupted immune responses,and impaired the ability of the host to clear infection,ultimately leading to mortality.These findings underscore the critical role of sRNA113 in regulating the virulence of P.plecoglossicida and its interaction with host immune defenses.This study provides a foundation for further exploration of sRNAmediated mechanisms in bacterial pathogenesis and hostpathogen interactions,contributing to a deeper understanding of virulence regulation and immune evasion in aquatic pathogens.展开更多
Black tents,also known as black yak-wool tents due to their construction from yak wool,serve as the traditional accommodation for ethnic Tibetan nomads.From ancient times till now,these tents have long captured the no...Black tents,also known as black yak-wool tents due to their construction from yak wool,serve as the traditional accommodation for ethnic Tibetan nomads.From ancient times till now,these tents have long captured the nomadic life of herdsmen living on the Qinghai-Xizang Plateau.展开更多
AIM:To summarize 10 surgical pearls for managing proliferative diabetic retinopathy(PDR)adapted from the ancient Chinese allusions and analyze the application of these pearls in a real-world fashion.METHODS:Retrospect...AIM:To summarize 10 surgical pearls for managing proliferative diabetic retinopathy(PDR)adapted from the ancient Chinese allusions and analyze the application of these pearls in a real-world fashion.METHODS:Retrospective,noncomparative,interventional study.Ten surgical pearls were summarized and adapted from the ancient Chinese philosophy.Totally 346 cases(443 eyes)that underwent pars plana vitrectomy(PPV)at our hospial from January 2016 to February 2024 were selected.Flexible combinations of these pearls were applied according to the specific condition of each patient during surgeries.The efficacy and safety were analyzed,as well as the application frequencies according to the existence of tractional retinal detachment or not.RESULTS:A total of 473 times of surgeries were performed on all the patients.According to ancient Chinese allusions,ten surgical pearls were summarized from these surgeries.All PPVs went smoothly with the application of different combinations.Finally,almost all proliferative membranes were successfully peeled except for 10 patients(11 eyes),who went through strategy No.10(minimal membranectomy)that,only necessary relaxation incisions were made with most of the proliferative membranes left on purpose.The final visual acuities were mostly improved or stable(1.92±0.83 LogMAR preoperatively vs 1.16±0.85 LogMAR postoperatively,P<0.01).Postoperative complications mainly included early inflammatory responses in the anterior chamber and nuclear sclerosis.Recurrent vitreous hemorrhage,retinal detachment,and hyphema or neovascular glaucoma occurred in 1.9%(9/473),3.2%(15/473),0.4%(2/473)and 0.4%(2/473)times of PPVs,respectively.After 12/473(2.5%)times of PPVs,retinal detachment at the macular area still existed,and multiple times of subsequent PPVs were conducted.Final retinal attachment at the macular area was realized in 98.9%eyes.Those 5 unattached eyes were with heavily reproliferated membranes and subsequent tractional retinal detachment recurrence under the oil,and three of them were scleral buckled additionally.CONCLUSION:These 10 surgical strategies and technique pearls were mostly effective and safe in the management of severe PDR patients.They were relatively easy to be memorized and applicated once the meaning of each Chinese idiom was understood.One can use different combinations flexibly according to a patient’s specific condition.展开更多
The compositions and distributions of monoterpenes,isoprene,aromatics and sesquiterpene SOA tracers(SOAM,SOAI,SOAA and SOAS,respectively)at an island site(Da Wan Shan Island,DWS)were investigated in the context of the...The compositions and distributions of monoterpenes,isoprene,aromatics and sesquiterpene SOA tracers(SOAM,SOAI,SOAA and SOAS,respectively)at an island site(Da Wan Shan Island,DWS)were investigated in the context of the influence of continental and marine air masses over the Pearl River Estuary(PRE)region in winter 2021.The sum concentration of SOA tracers was 6.2–132.8 ng m^(−3),with SOAM and SOAI as the main components in both continental(scenarios A1 and A2)and marine air masses(scenario A3),as well as their combination(scenario A4).The highest and lowest levels of SOAM were observed in A1 and A3,respectively,which were mainly related to the variations in meteorological conditions,precursor concentrations,and the degree of photochemical processes.Higher MBTCA/HGA(3-methyl-1,2,3-butanetricarboxylic acid/3-hydroxyglutaric acid)ratios suggested a less significant contribution fromα-pinene to SOAM.The variations of SOAI in the different scenarios were associated with differences in relative humidity,particle acidity,and isoprene/NOx ratios.The respective highest and lowest concentrations of aromatics SOA tracers in A1 and A3 revealed the influence of anthropogenic precursors from upwind continental areas,which was confirmed by the correlation among biogenic and anthropogenic precursors.The results of the tracer-based-method suggested dominant contributions of SOAs from aromatics and monoterpenes,with the highest concentrations in A1.A WRF-Chem simulation revealed that the SOAs from the above precursors only contributed 12%–25%to the total SOA at DWS,while the spatial distributions of SOAs further highlighted that the abundance of SOAs over the PRE region in winter is highly associated with air masses transported from upwind continental areas.展开更多
The Pearl River Delta(PRD)region has been identified as a significant hotspot of wet ammonium deposition.However,the absence of long-term monitoring data in the area hinders the comprehension of the historical trends ...The Pearl River Delta(PRD)region has been identified as a significant hotspot of wet ammonium deposition.However,the absence of long-term monitoring data in the area hinders the comprehension of the historical trends and changes in wet NH_(4)^(+)-N deposition in response to emissions,which interferes with the ability to make effective decisions.This study has analyzed the long-term trends of wet NH_(4)^(+)-N deposition flux and has quantified the effect of anthropogenic emissions and meteorological factors at a typical urban site and a typical forest site in the PRD region from 2009 to 2020.It revealed a significant decreasing trend in wet NH_(4)^(+)-N flux in both the typical urban and forest areas of the PRD region,at-6.2%/year(p<0.001)and-3.3%/year(p<0.001),respectively.Anthropogenic emissions are thought to have contributed 47%–57%of the wet NH_(4)^(+)-N deposition trend over the past 12 years compared to meteorological factors.Meteorological conditions dominated the interannual fluctuations in wet NH_(4)^(+)-N deposition with an absolute contribution of 46%–52%,while anthropogenic emissions change alone explained 10%–31%.NH_(3)emissions have the greatest impact on the urban area among anthropogenic emission factors,while SO_(2)emissions have the greatest impact on the forest area.Additionally,precipitation was identified as the primary meteorological driver for both sites.Our findings also imply that the benefits of NH_(3)emissions reductions might not immediately emerge due to interference from weather-related factors.展开更多
The perfection of the cross-border regional innovation system of the Pearl River Delta(PRD)and Hong Kong region remarkably underpins the construction of the Guangdong-Hong Kong-Macao Greater Bay Area(GBA)towards an in...The perfection of the cross-border regional innovation system of the Pearl River Delta(PRD)and Hong Kong region remarkably underpins the construction of the Guangdong-Hong Kong-Macao Greater Bay Area(GBA)towards an international technological innovation hub.This paper focuses on the relational characteristics of the usage of technological innovation functions and elements,including labor force,technology,and producer services from Hong Kong region by high-technology firms in the PRD,and probes into the influencing factors by integrating the objective perspective on the impact of firm-level socioeconomic attributes and subjective perspective on the open interpretations on the reasons by using or not using technological innovation functions and elements from Hong Kong region by various stakeholders in high-technology domains in the PRD.Key research findings are fourfold.First,Hong Kong's technological innovation functions primarily ride on its institutional advantages under the“One Country,Two Systems”framework to empower high-technology firms in the PRD by expanding their international market,international business operation,and financing,but cross-border investment and entrepreneurship has retrieved to a relatively marginalized position.The degree of supply-demand relations of producer services is the highest,followed by labor force and technology.Second,Hong Kong-invested,large-sized,and long-standing high-technology firms in the PRD are more inclined to use technological innovation elements from Hong Kong region,while domestic,small-and-medium-sized,and start-up high-technology firms in the PRD are in turn,gradually unhooked from the supply of technological innovation elements from Hong Kong region.Third,Hong Kong enjoys both advantages and disadvantages in supplying labor forces,technologies,and producer services to high-technology firms in the PRD,with advantages in competitiveness,international linkages and visions,and disadvantages in high cost,lack of more profound mutual understanding between Hong Kong and the PRD,and the imperfect cooperation mechanisms.Fourth,interactions among the transitioning role of Hong Kong region in the macro-level global and national economic development landscape,meso-level cross-border regional specificities under the“One Country,Two Systems”framework,and micro-level heterogeneous practices and capabilities of firms influence the usage of technological innovation functions and elements from Hong Kong region by high-technology firms in the PRD.展开更多
The Zhujiang(Pearl)River Mouth Basin(PRMB)is located in the northern part of the South China Sea,and it is one of China’s three major offshore hydrocarbon-rich basins,playing an indispensable role in meeting the coun...The Zhujiang(Pearl)River Mouth Basin(PRMB)is located in the northern part of the South China Sea,and it is one of China’s three major offshore hydrocarbon-rich basins,playing an indispensable role in meeting the country’s energy needs.Exploration for oil in the PRMB started early and has achieved remarkable results in some sags,but many sags have yet to yield significant discoveries,necessitating the search for new favorable exploration areas.The aim of this study is to analyze the deep structural characteristics of various sags in the PRMB and predict favorable exploration areas,providing corresponding support for the next strategic breakthrough in oil exploration.Some studies indicate a certain relationship between the Moho depth and crustal thickness and the occurrence of oil.In this paper,based on satellite altimetry gravity anomaly data,we utilize a Moho depth inversion method based on variable residual crustal density to obtain the Moho depth in the PRMB,from which the crustal thickness and crustal stretching factor of the basin are calculated.The results show that the Moho depth in the PRMB ranges from 10 km to 37 km,the crustal thickness ranges from 7 km to 35 km,and the crustal stretching factor ranges from 0.9 to 3.0.Finally,we propose a comprehensive evaluation scheme for oil resoureces based on the CRiteria Importance Through Intercriteria Correlation(CRITIC)method,which comprehensively evaluates multiple factors,such as the Cenozoic sedimentary filling scale,Cenozoic thickness,Moho depth,crustal thickness,and crustal stretching factor,and provides evaluation criteria for identifying hydrocarbon-rich sags.According to this evaluation scheme,the exploration potential is relatively high in the Liwan Sag,Jinghai Sag,Heshan Sag,and Jieyang Sag,which are favorable exploration areas.展开更多
Based on a set of high-resolution 3D seismic data from the northern continental margin of the South China Sea,the lithospheric structure,thinning mechanisms and related syn-rift tectonic deformation response processes...Based on a set of high-resolution 3D seismic data from the northern continental margin of the South China Sea,the lithospheric structure,thinning mechanisms and related syn-rift tectonic deformation response processes in the crustal necking zone in the deepwater area of the Pearl River Mouth Basin were systematically analyzed,and the petroleum geological significance was discussed.The necking zone investigated in the study is located in the Baiyun Sag and Kaiping Sag in the deepwater area of the Pearl River Mouth Basin.These areas show extreme crustal thinned geometries of central thinning and flank thickening,characterized by multi-level and multi-dipping detachment fault systems.The necking zone exhibits pronounced lateral heterogeneity in structural architectures,which can be classified into four types of thinned crustal architectures,i.e.the wedge-shaped extremely thinned crustal architecture in the Baiyun Main Sub-sag,dumbbell-shaped moderately thinned crustal architecture in the Baiyun West Sub-sag,box-shaped weakly thinned crustal architecture in eastern Baiyun Sag,and metamorphic core complex weakly thinned crustal architecture in the Kaiping Sag.This shows great variations in the degree and style of crustal thinning,types of detachment faults,distribution of syn-rift sedimentary sequences,and intensity of magmatism.The thinning of the necking zone is controlled by the heterogeneous rheological stratification of lithosphere,intensity of mantle-derived magmatism,and deformation modes of detachment faults.The syn-rift tectonic deformation of the necking zone evolved through three phases,i.e.uniform stretching during the early Wenchang Formation deposition period,necking during the late Wenchang Formation deposition period,and hyperextension during the Enping Formation deposition period.The crustal thinning extent and architectural differentiation in these phases were primarily controlled by three distinct mechanisms,i.e.the pure shear deformation activation of pre-existing thrust faults,the simple shear deformation of crust-mantle and inter-crust detachment faults,and differential coupling of lower crustal flow and ductile domes with main detachment faults.The hydrocarbon accumulation and enrichment in the necking zone exhibit marked spatial heterogeneity.Four distinct crustal thinned architecture-hydrocarbon accumulation models were identified in this study.The hydrocarbon accumulations in the shallow part exhibit significant correlations with their deep crustal thinned architectures.The unique lithospheric structure and deformation process predominantly control the favorable hydrocarbon accumulation zones with excellent source-fault-ridge-sand configurations,which is critical to reservoir-forming.The most promising exploration targets are mainly identified on the uplift zones and their seaward-dipping flanks associated with the middle and lower crustal domes.This research provides additional insights into lithospheric thinning-breakup process at intermediate continental margins of marine sedimentary basins,being significant for guiding the deepwater petroleum exploration in the Pearl River Mouth Basin.展开更多
This paper provides a comprehensive reflection on the evolution of globalization research in the Pearl River Delta(PRD),considering the current international context and national strategies.It identifies several chall...This paper provides a comprehensive reflection on the evolution of globalization research in the Pearl River Delta(PRD),considering the current international context and national strategies.It identifies several challenges in existing studies,such as the ambiguity of globalization patterns and the insufficient representativeness of key indicators.In response to these challenges,this paper draws upon the theory of strategic coupling to propose a new theoretical framework for analyzing globalization in latecomer regions.Based on the concepts of spatial stickiness and locational advantages,this paper further develops a two-dimensional quantitative indicator matrix.Using the PRD as a case study,it conducts empirical measurements and analysis,leading to three main conclusions.First,the theory of strategic coupling proves well-suited for analyzing the globalization of latecomer regions,exemplified by the PRD.It offers a more systematic,clearer,and more robust explanatory framework compared to traditional measurement methods.Second,the empirical analysis from the PRD reveals that the pattern of regional globalization does not follow a simple linear growth or cyclical model.Instead,it exhibits a circuitous,complex,and upward spiral,unfolding along an S-shaped evolutionary trajectory.Third,through comparisons of the eastern and western shores,as well as segmented city analyses,this study finds that locational advantages significantly shape the evolutionary pattern of globalization.This influence is not only apparent during the region's initial take-off phase but also plays a more profound role in shaping its subsequent developmental trajectory.This study makes a distinctive contribution to both the theoretical understanding of globalization in latecomer regions and the practical field of regional economic development in China.Additionally,it introduces a novel measurement approach for studying regional globalization.展开更多
The surveys on the COD in the Lingdingyang waters of Pearl River estuary were carried out in May and August of 2002. The results showed that the concentrations of COD in the waters ranged from 0,41 to 2.72 mg·L^-...The surveys on the COD in the Lingdingyang waters of Pearl River estuary were carried out in May and August of 2002. The results showed that the concentrations of COD in the waters ranged from 0,41 to 2.72 mg·L^-1 with an average of 1.21 mg·L^-1.The spatial distributions showed that COD concentration decreased gradually from the north to south of Pearl River estuary, and the concentration near coastal waters was higher than that in offshore waters. The concentration of COD in summer was higher than in spring. Evaluated by the first class （COD ≤ 2 mg·L^-1） of sea water quality standard （Chinese standard）, there were about 15 % of COD concentrations over the standard. The concentration of COD showed a positive correlation with the concentration of suspend substances in spring and summer, but in summer it showed a negative correlation with the concentrations of inorganic nitrate and phosphate.展开更多
Biofouling is a particular problem in the pearl oyster culture. It may reduce the growth and survival rates of the cultured species. Foulers are often themselves filter feeders, and are therefore potential competitors...Biofouling is a particular problem in the pearl oyster culture. It may reduce the growth and survival rates of the cultured species. Foulers are often themselves filter feeders, and are therefore potential competitors for food resource with the cultured species. Fouling organisms may also reduce the oxygen supply. A study was conducted to measure the impact of foulers on feeding oxygen consumption, and waste excretion. POM, ammonia, phosphate and oxygen concentration were measured in various treatments （cultured species, foulers）. This study showed that fouling organisms had significant effect on food uptake, oxygen consumption and waste excretion. The clearance rate, ammonia and phosphate release rate, oxygen consumption rate of the fouled pearl oyster were greater than those of the clean pearl oysters. Other foulers that settled on cages or buoys also contributed much to phytoplankton depletion, oxygen consumption and concentration increase of ammonia and phosphate in water. Therefore, this study showed us that foulers were important competitors in the pearl oyster cultivation of Daya Bay in November 2005.展开更多
Taking advantage of remote sensing(RS) technology and geographic information system(GIS) technology to interpret the four periods' data of remote sensing images of Pearl River Estuary in the years of 1990,1995,200...Taking advantage of remote sensing(RS) technology and geographic information system(GIS) technology to interpret the four periods' data of remote sensing images of Pearl River Estuary in the years of 1990,1995,2000,and 2005,the changes in land utilization and landscape layout of Pearl River Estuary have been analyzed with reference to land utilization dynamic model and quantitative method in landscape ecology.Results indicate several points as followings.①Located in the region typical of high-speed economic development,Pearl River Estuary shows noticeable changes in land types and evident spatial temporal difference.During these 15 years,the areas of cultivated land and forests have experienced dramatic decline while the land for construction purposes shows the trend of powerful increase.②On the prospect of variation,landscape metrics have indicated great differences among other landscape pattern indices except for Area-Weighted Mean Patch Fractal Dimension(AWMPFD) especially during the period from 1990 to 1995 which experiences the most obvious changes.③On the prospect of landscape,landscape pattern indices also indicate great changes in the landscape layout of Pearl River Estuary from 1990 to 2005 as well as noticeable increase in the number of patches,and various landscape pattern indices show the increase in the degree of regional landscape fragmentation and increase in diversity.展开更多
Evapotranspiration ratio of six major forest types in the Pearl River Delta was studied in this paper, and the six forest types included eucalyptus forest, fruit forest, coniferous forest, shrub forest, coniferous for...Evapotranspiration ratio of six major forest types in the Pearl River Delta was studied in this paper, and the six forest types included eucalyptus forest, fruit forest, coniferous forest, shrub forest, coniferous forest, and broad-leaved mixed for- est. The mechanism of PT-T model was analyzed based on Priestley-Taylor ex- tended model, and the result showed that land surface temperature or temperature difference between day and night could be used to evaluate the evapotranspiration factor. The evapotranspiration of 6 forest types was estimated with MODIS data and TM data and weather information during 2008-2009. The result suggested that water consumption of different forest differs insignificantly, and the EF of eucalyptus is not high.展开更多
文摘On the tranquil waters of Xiaoshanyang,a small lake in Deqing County,Zhejiang Province,rows of white,spherical buoys are lined up in perfect order,resembling strands of pearl necklaces.Once a thousand-year-old pearl-farming site,this heritage-rich waterbody has emerged as a global benchmark for the preservation of agricultural heritage.
基金National Social Science Foundation Program,No.22VRC163National Natural Science Foundation of China,No.42061043+1 种基金Postgraduate Research&Practice Innovation Program of Jiangsu Province,No.KYCX24_1008Innovation Project of Guangxi Graduate Education,No.YCSW2024473。
文摘Clarifying the mechanisms that control the evolution of territorial space patterns is essential for regulating and optimizing the geographical structure and processes related to sustainable development.Using the Guangdong and Guangxi sections of the Pearl River Basin as examples,the transfer-matrix method and standard deviation ellipse model were applied to characterize the evolution of territorial space patterns from 1990 to 2020.A trend surface analysis and the Theil index were used to analyze regional differences in the evolution process,and geodetectors were used to identify the underlying mechanisms of the changes.There were three key results.(1)In these critical areas of the Pearl River Basin,agricultural and ecological spaces have rapidly declined due to urban expansion,with transfers between these spaces dominating the evolution of territorial space patterns.Spatial pattern changes in the Guangdong section were more intense than in the Guangxi section.(2)Regional differences in urban space have decreased,whereas differences in agricultural and ecological spaces have intensified.Driven by socio-economic growth,the cross-regional transfers of territorial space have created a“high in the east,while low in the west”inter-regional difference,and a“high in the south,while low in the north”intra-regional difference shaped by natural conditions.The regional differences in space patterns were greater in Guangdong than in Guangxi.(3)The evolution of watershed territorial space patterns resulted from scale changes,locational shifts,structural reorganizations,and directional changes driven by multiple factors.Natural environment,social life,economic development,and policy factors played foundational,leading,key driving,and guiding roles,respectively.Additionally,the regional differences in the evolution of watershed territorial space patterns originated from the differential transmission of the influence of various factors affecting spatial evolution.Enhancing urban space efficiency,restructuring agricultural space,and optimizing ecological space are key strategies for building a complementary and synergistic territorial space pattern in the basin.
基金Supported by the Research Project of China National Offshore Oil Corporation(SCKY-2023-HN-3)。
文摘Based on the comprehensive analysis of data from petrology and mineralogy,well logging,seismic surveys,paleontology,and geochemistry,a detailed research was conducted on paleoenvironmental and paleoclimatic conditions,and modeling of the source rocks in the second member of the Eocene Wenchang Formation(Wen 2 Member)in the Northern Shunde Subsag at the southwestern margin of the Pearl River Mouth Basin.The Wen 2 Member hosts excellent,thick lacustrine source rocks with strong longitudinal heterogeneity and an average total organic carbon(TOC)content of over 4.9%.The Wen 2 Member can be divided into three units(I,II,III)from bottom to top.Unit I features excellent source rocks with Type I organic matters(average TOC of 5.9%)primarily sourced from lake organisms;Unit II hosts source rocks dominated by Type II2 organic matters(average TOC of 2.2%),which are originated from mixed sources dominated by terrestrial input.Unit III contains good to excellent source rocks dominated by Type II1 organic matters(average TOC of 4.9%),which are mainly contributed by lake organisms and partially by terrestrial input.Under the background of rapid subsidence and limited source supply during intense rifting period in the Eocene,excellent source rocks were developed in Wen 2 Member in the Northern Shunde Subsag under the coordinated control of warm and humid climate,volcanic activity,and deep-water reducing conditions.During the deposition of Unit I,the warm and humid climate and volcanic activity promoted the proliferation of lake algaes,primarily Granodiscus,resulting in high initial productivity,and deep-water reducing conditions enabled satisfactory preservation of organic matters.These factors jointly controlled the development and occurrence of excellent source rocks.During the deposition of Unit II,a transition from warm to cool and semi-arid paleoclimatic conditions led to a decrease in lake algaes and initial productivity.Additionally,enhanced terrestrial input and shallow-water,weakly oxidizing water conditions caused a significant dilution and decomposition of organic matters,degrading the quality of source rocks.During the deposition of Unit III,when the paleoclimatic conditions are cool and humid,Pediastrum and Botryococcus began to thrive,leading to an increase in productivity.Meanwhile,the reducing environment of semi-deep water facilitated the preservation of excellent source rocks,albeit slightly inferior to those in Unit I.The study results clarify the differential origins and development models of various source rocks in the Shunde Sag,offering valuable guidance for evaluating source rocks and selecting petroleum exploration targets in similar marginal sags.
基金supported by the National Natural Science Foundation of China (32373181)National Key Research and Development Program (2023YFD2400700)+2 种基金Science and Technology Plan Project of Fujian Province (2022L3059)High-quality Development of Marine and Fishery Industry Special Fund Project of Fujian Province (FJHYF-L-2023-5)Open Fund of Fujian Province Key Laboratory of Special Aquatic Formula Feed (TMKJZ2302)。
文摘Small RNAs(sRNAs)are a class of molecules capable of perceiving environmental changes and exerting posttranscriptional regulation over target gene expression,thereby influencing bacterial virulence and host immune responses.Pseudomonas plecoglossicida is a pathogenic bacterium that poses a significant threat to aquatic animal health.However,the regulatory mechanisms of sRNAs in P.plecoglossicida remain unclear.This study focused on sRNA113,previously identified as a potential regulator of the fliP gene,a key component of the lateral flagellar type III secretion system.To investigate the effects of sRNA113on P.plecoglossicida virulence,as well as its role in regulating pathogenic processes and host immune responses,mutant strains lacking this sRNA were generated and analyzed.Deletion of sRNA113 resulted in the up-regulation of lateral flagellar type III secretion system-related genes in P.plecoglossicida,which enhanced bacterial swarming motility,biofilm formation,and chemotaxis ability in vitro.In vivo infection experiments with pearl gentian grouper revealed that sRNA113 deletion enhanced the pathogenicity of P.plecoglossicida.This heightened virulence was attributed to the up-regulation of genes associated with the lateral flagellar type III secretion system,resulting in higher bacterial loads within host tissues.This amplification of pathogenic activity intensified tissue damage,disrupted immune responses,and impaired the ability of the host to clear infection,ultimately leading to mortality.These findings underscore the critical role of sRNA113 in regulating the virulence of P.plecoglossicida and its interaction with host immune defenses.This study provides a foundation for further exploration of sRNAmediated mechanisms in bacterial pathogenesis and hostpathogen interactions,contributing to a deeper understanding of virulence regulation and immune evasion in aquatic pathogens.
文摘Black tents,also known as black yak-wool tents due to their construction from yak wool,serve as the traditional accommodation for ethnic Tibetan nomads.From ancient times till now,these tents have long captured the nomadic life of herdsmen living on the Qinghai-Xizang Plateau.
文摘AIM:To summarize 10 surgical pearls for managing proliferative diabetic retinopathy(PDR)adapted from the ancient Chinese allusions and analyze the application of these pearls in a real-world fashion.METHODS:Retrospective,noncomparative,interventional study.Ten surgical pearls were summarized and adapted from the ancient Chinese philosophy.Totally 346 cases(443 eyes)that underwent pars plana vitrectomy(PPV)at our hospial from January 2016 to February 2024 were selected.Flexible combinations of these pearls were applied according to the specific condition of each patient during surgeries.The efficacy and safety were analyzed,as well as the application frequencies according to the existence of tractional retinal detachment or not.RESULTS:A total of 473 times of surgeries were performed on all the patients.According to ancient Chinese allusions,ten surgical pearls were summarized from these surgeries.All PPVs went smoothly with the application of different combinations.Finally,almost all proliferative membranes were successfully peeled except for 10 patients(11 eyes),who went through strategy No.10(minimal membranectomy)that,only necessary relaxation incisions were made with most of the proliferative membranes left on purpose.The final visual acuities were mostly improved or stable(1.92±0.83 LogMAR preoperatively vs 1.16±0.85 LogMAR postoperatively,P<0.01).Postoperative complications mainly included early inflammatory responses in the anterior chamber and nuclear sclerosis.Recurrent vitreous hemorrhage,retinal detachment,and hyphema or neovascular glaucoma occurred in 1.9%(9/473),3.2%(15/473),0.4%(2/473)and 0.4%(2/473)times of PPVs,respectively.After 12/473(2.5%)times of PPVs,retinal detachment at the macular area still existed,and multiple times of subsequent PPVs were conducted.Final retinal attachment at the macular area was realized in 98.9%eyes.Those 5 unattached eyes were with heavily reproliferated membranes and subsequent tractional retinal detachment recurrence under the oil,and three of them were scleral buckled additionally.CONCLUSION:These 10 surgical strategies and technique pearls were mostly effective and safe in the management of severe PDR patients.They were relatively easy to be memorized and applicated once the meaning of each Chinese idiom was understood.One can use different combinations flexibly according to a patient’s specific condition.
基金supported by the State Key Program of the National Natural Science Foundation of China(Grant Nos.42230701,91644215)the National Natural ScienceFoundation of China(Grant Nos.42122062 and 42307137)+3 种基金the Guangdong Basic and Applied Basic Research Foundation(Grant No.2022A1515010852)the Fundamental Research Funds for the Central Universities,Sun Yat-sen University(Grant No.23hytd002)the Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)(Grant No.SML2023SP218)L.M.acknowledges the Zhuhai Science and Technology Plan Project(Grant No.ZH22036201210115PWC).
文摘The compositions and distributions of monoterpenes,isoprene,aromatics and sesquiterpene SOA tracers(SOAM,SOAI,SOAA and SOAS,respectively)at an island site(Da Wan Shan Island,DWS)were investigated in the context of the influence of continental and marine air masses over the Pearl River Estuary(PRE)region in winter 2021.The sum concentration of SOA tracers was 6.2–132.8 ng m^(−3),with SOAM and SOAI as the main components in both continental(scenarios A1 and A2)and marine air masses(scenario A3),as well as their combination(scenario A4).The highest and lowest levels of SOAM were observed in A1 and A3,respectively,which were mainly related to the variations in meteorological conditions,precursor concentrations,and the degree of photochemical processes.Higher MBTCA/HGA(3-methyl-1,2,3-butanetricarboxylic acid/3-hydroxyglutaric acid)ratios suggested a less significant contribution fromα-pinene to SOAM.The variations of SOAI in the different scenarios were associated with differences in relative humidity,particle acidity,and isoprene/NOx ratios.The respective highest and lowest concentrations of aromatics SOA tracers in A1 and A3 revealed the influence of anthropogenic precursors from upwind continental areas,which was confirmed by the correlation among biogenic and anthropogenic precursors.The results of the tracer-based-method suggested dominant contributions of SOAs from aromatics and monoterpenes,with the highest concentrations in A1.A WRF-Chem simulation revealed that the SOAs from the above precursors only contributed 12%–25%to the total SOA at DWS,while the spatial distributions of SOAs further highlighted that the abundance of SOAs over the PRE region in winter is highly associated with air masses transported from upwind continental areas.
基金supported by the National Natural Science Foundation(Nos.42275107,42121004,and 42375109)the National Key Research and Development Plan(No.2023YFC3706202)+1 种基金the Foundational and Applied Basic Research in Guangzhou in 2023(No.2023A04J0251)the Special Fund Project for Science and Technology Innovation Strategy of Guangdong Province(No.2019B121205004).
文摘The Pearl River Delta(PRD)region has been identified as a significant hotspot of wet ammonium deposition.However,the absence of long-term monitoring data in the area hinders the comprehension of the historical trends and changes in wet NH_(4)^(+)-N deposition in response to emissions,which interferes with the ability to make effective decisions.This study has analyzed the long-term trends of wet NH_(4)^(+)-N deposition flux and has quantified the effect of anthropogenic emissions and meteorological factors at a typical urban site and a typical forest site in the PRD region from 2009 to 2020.It revealed a significant decreasing trend in wet NH_(4)^(+)-N flux in both the typical urban and forest areas of the PRD region,at-6.2%/year(p<0.001)and-3.3%/year(p<0.001),respectively.Anthropogenic emissions are thought to have contributed 47%–57%of the wet NH_(4)^(+)-N deposition trend over the past 12 years compared to meteorological factors.Meteorological conditions dominated the interannual fluctuations in wet NH_(4)^(+)-N deposition with an absolute contribution of 46%–52%,while anthropogenic emissions change alone explained 10%–31%.NH_(3)emissions have the greatest impact on the urban area among anthropogenic emission factors,while SO_(2)emissions have the greatest impact on the forest area.Additionally,precipitation was identified as the primary meteorological driver for both sites.Our findings also imply that the benefits of NH_(3)emissions reductions might not immediately emerge due to interference from weather-related factors.
基金National Natural Science Foundation of China,No.42301203Strategic Public Policy Research Grant of the Policy Innovation and Coordination Office of the Hong Kong SAR Government,No.S2017.A8.007.17S+2 种基金Guangdong Basic and Applied Basic Research Foundation,No.2022A1515110969Major Program of National Social Science Foundation of China,No.21&ZD107GDAS’Project of Science and Technology Development,No.2023GDASZH-2023010101。
文摘The perfection of the cross-border regional innovation system of the Pearl River Delta(PRD)and Hong Kong region remarkably underpins the construction of the Guangdong-Hong Kong-Macao Greater Bay Area(GBA)towards an international technological innovation hub.This paper focuses on the relational characteristics of the usage of technological innovation functions and elements,including labor force,technology,and producer services from Hong Kong region by high-technology firms in the PRD,and probes into the influencing factors by integrating the objective perspective on the impact of firm-level socioeconomic attributes and subjective perspective on the open interpretations on the reasons by using or not using technological innovation functions and elements from Hong Kong region by various stakeholders in high-technology domains in the PRD.Key research findings are fourfold.First,Hong Kong's technological innovation functions primarily ride on its institutional advantages under the“One Country,Two Systems”framework to empower high-technology firms in the PRD by expanding their international market,international business operation,and financing,but cross-border investment and entrepreneurship has retrieved to a relatively marginalized position.The degree of supply-demand relations of producer services is the highest,followed by labor force and technology.Second,Hong Kong-invested,large-sized,and long-standing high-technology firms in the PRD are more inclined to use technological innovation elements from Hong Kong region,while domestic,small-and-medium-sized,and start-up high-technology firms in the PRD are in turn,gradually unhooked from the supply of technological innovation elements from Hong Kong region.Third,Hong Kong enjoys both advantages and disadvantages in supplying labor forces,technologies,and producer services to high-technology firms in the PRD,with advantages in competitiveness,international linkages and visions,and disadvantages in high cost,lack of more profound mutual understanding between Hong Kong and the PRD,and the imperfect cooperation mechanisms.Fourth,interactions among the transitioning role of Hong Kong region in the macro-level global and national economic development landscape,meso-level cross-border regional specificities under the“One Country,Two Systems”framework,and micro-level heterogeneous practices and capabilities of firms influence the usage of technological innovation functions and elements from Hong Kong region by high-technology firms in the PRD.
基金The Fundamental Research Funds for the Central Universities,CHD,under contract No.300102264106the Shaanxi Natural Science Basic Research Program under contract No.2025JC-YBQN-370the Scientific and Technological Project of CNOOC Research Institute Co.,Ltd.under contract No.CCL2021RCPS0167KQN.
文摘The Zhujiang(Pearl)River Mouth Basin(PRMB)is located in the northern part of the South China Sea,and it is one of China’s three major offshore hydrocarbon-rich basins,playing an indispensable role in meeting the country’s energy needs.Exploration for oil in the PRMB started early and has achieved remarkable results in some sags,but many sags have yet to yield significant discoveries,necessitating the search for new favorable exploration areas.The aim of this study is to analyze the deep structural characteristics of various sags in the PRMB and predict favorable exploration areas,providing corresponding support for the next strategic breakthrough in oil exploration.Some studies indicate a certain relationship between the Moho depth and crustal thickness and the occurrence of oil.In this paper,based on satellite altimetry gravity anomaly data,we utilize a Moho depth inversion method based on variable residual crustal density to obtain the Moho depth in the PRMB,from which the crustal thickness and crustal stretching factor of the basin are calculated.The results show that the Moho depth in the PRMB ranges from 10 km to 37 km,the crustal thickness ranges from 7 km to 35 km,and the crustal stretching factor ranges from 0.9 to 3.0.Finally,we propose a comprehensive evaluation scheme for oil resoureces based on the CRiteria Importance Through Intercriteria Correlation(CRITIC)method,which comprehensively evaluates multiple factors,such as the Cenozoic sedimentary filling scale,Cenozoic thickness,Moho depth,crustal thickness,and crustal stretching factor,and provides evaluation criteria for identifying hydrocarbon-rich sags.According to this evaluation scheme,the exploration potential is relatively high in the Liwan Sag,Jinghai Sag,Heshan Sag,and Jieyang Sag,which are favorable exploration areas.
基金Supported by the Prospective Basic Research Project of CNOOC China Limited(KJQZ-2023-2001)Major Science and Technology Project of CNOOC(KJGG2022-0103-03).
文摘Based on a set of high-resolution 3D seismic data from the northern continental margin of the South China Sea,the lithospheric structure,thinning mechanisms and related syn-rift tectonic deformation response processes in the crustal necking zone in the deepwater area of the Pearl River Mouth Basin were systematically analyzed,and the petroleum geological significance was discussed.The necking zone investigated in the study is located in the Baiyun Sag and Kaiping Sag in the deepwater area of the Pearl River Mouth Basin.These areas show extreme crustal thinned geometries of central thinning and flank thickening,characterized by multi-level and multi-dipping detachment fault systems.The necking zone exhibits pronounced lateral heterogeneity in structural architectures,which can be classified into four types of thinned crustal architectures,i.e.the wedge-shaped extremely thinned crustal architecture in the Baiyun Main Sub-sag,dumbbell-shaped moderately thinned crustal architecture in the Baiyun West Sub-sag,box-shaped weakly thinned crustal architecture in eastern Baiyun Sag,and metamorphic core complex weakly thinned crustal architecture in the Kaiping Sag.This shows great variations in the degree and style of crustal thinning,types of detachment faults,distribution of syn-rift sedimentary sequences,and intensity of magmatism.The thinning of the necking zone is controlled by the heterogeneous rheological stratification of lithosphere,intensity of mantle-derived magmatism,and deformation modes of detachment faults.The syn-rift tectonic deformation of the necking zone evolved through three phases,i.e.uniform stretching during the early Wenchang Formation deposition period,necking during the late Wenchang Formation deposition period,and hyperextension during the Enping Formation deposition period.The crustal thinning extent and architectural differentiation in these phases were primarily controlled by three distinct mechanisms,i.e.the pure shear deformation activation of pre-existing thrust faults,the simple shear deformation of crust-mantle and inter-crust detachment faults,and differential coupling of lower crustal flow and ductile domes with main detachment faults.The hydrocarbon accumulation and enrichment in the necking zone exhibit marked spatial heterogeneity.Four distinct crustal thinned architecture-hydrocarbon accumulation models were identified in this study.The hydrocarbon accumulations in the shallow part exhibit significant correlations with their deep crustal thinned architectures.The unique lithospheric structure and deformation process predominantly control the favorable hydrocarbon accumulation zones with excellent source-fault-ridge-sand configurations,which is critical to reservoir-forming.The most promising exploration targets are mainly identified on the uplift zones and their seaward-dipping flanks associated with the middle and lower crustal domes.This research provides additional insights into lithospheric thinning-breakup process at intermediate continental margins of marine sedimentary basins,being significant for guiding the deepwater petroleum exploration in the Pearl River Mouth Basin.
基金National Natural Science Foundation of China,No.42271182,No.42122006,No.42101171。
文摘This paper provides a comprehensive reflection on the evolution of globalization research in the Pearl River Delta(PRD),considering the current international context and national strategies.It identifies several challenges in existing studies,such as the ambiguity of globalization patterns and the insufficient representativeness of key indicators.In response to these challenges,this paper draws upon the theory of strategic coupling to propose a new theoretical framework for analyzing globalization in latecomer regions.Based on the concepts of spatial stickiness and locational advantages,this paper further develops a two-dimensional quantitative indicator matrix.Using the PRD as a case study,it conducts empirical measurements and analysis,leading to three main conclusions.First,the theory of strategic coupling proves well-suited for analyzing the globalization of latecomer regions,exemplified by the PRD.It offers a more systematic,clearer,and more robust explanatory framework compared to traditional measurement methods.Second,the empirical analysis from the PRD reveals that the pattern of regional globalization does not follow a simple linear growth or cyclical model.Instead,it exhibits a circuitous,complex,and upward spiral,unfolding along an S-shaped evolutionary trajectory.Third,through comparisons of the eastern and western shores,as well as segmented city analyses,this study finds that locational advantages significantly shape the evolutionary pattern of globalization.This influence is not only apparent during the region's initial take-off phase but also plays a more profound role in shaping its subsequent developmental trajectory.This study makes a distinctive contribution to both the theoretical understanding of globalization in latecomer regions and the practical field of regional economic development in China.Additionally,it introduces a novel measurement approach for studying regional globalization.
文摘The surveys on the COD in the Lingdingyang waters of Pearl River estuary were carried out in May and August of 2002. The results showed that the concentrations of COD in the waters ranged from 0,41 to 2.72 mg·L^-1 with an average of 1.21 mg·L^-1.The spatial distributions showed that COD concentration decreased gradually from the north to south of Pearl River estuary, and the concentration near coastal waters was higher than that in offshore waters. The concentration of COD in summer was higher than in spring. Evaluated by the first class （COD ≤ 2 mg·L^-1） of sea water quality standard （Chinese standard）, there were about 15 % of COD concentrations over the standard. The concentration of COD showed a positive correlation with the concentration of suspend substances in spring and summer, but in summer it showed a negative correlation with the concentrations of inorganic nitrate and phosphate.
文摘Biofouling is a particular problem in the pearl oyster culture. It may reduce the growth and survival rates of the cultured species. Foulers are often themselves filter feeders, and are therefore potential competitors for food resource with the cultured species. Fouling organisms may also reduce the oxygen supply. A study was conducted to measure the impact of foulers on feeding oxygen consumption, and waste excretion. POM, ammonia, phosphate and oxygen concentration were measured in various treatments （cultured species, foulers）. This study showed that fouling organisms had significant effect on food uptake, oxygen consumption and waste excretion. The clearance rate, ammonia and phosphate release rate, oxygen consumption rate of the fouled pearl oyster were greater than those of the clean pearl oysters. Other foulers that settled on cages or buoys also contributed much to phytoplankton depletion, oxygen consumption and concentration increase of ammonia and phosphate in water. Therefore, this study showed us that foulers were important competitors in the pearl oyster cultivation of Daya Bay in November 2005.
文摘Taking advantage of remote sensing(RS) technology and geographic information system(GIS) technology to interpret the four periods' data of remote sensing images of Pearl River Estuary in the years of 1990,1995,2000,and 2005,the changes in land utilization and landscape layout of Pearl River Estuary have been analyzed with reference to land utilization dynamic model and quantitative method in landscape ecology.Results indicate several points as followings.①Located in the region typical of high-speed economic development,Pearl River Estuary shows noticeable changes in land types and evident spatial temporal difference.During these 15 years,the areas of cultivated land and forests have experienced dramatic decline while the land for construction purposes shows the trend of powerful increase.②On the prospect of variation,landscape metrics have indicated great differences among other landscape pattern indices except for Area-Weighted Mean Patch Fractal Dimension(AWMPFD) especially during the period from 1990 to 1995 which experiences the most obvious changes.③On the prospect of landscape,landscape pattern indices also indicate great changes in the landscape layout of Pearl River Estuary from 1990 to 2005 as well as noticeable increase in the number of patches,and various landscape pattern indices show the increase in the degree of regional landscape fragmentation and increase in diversity.
基金Supported by Guangdong Hydrotechnics Innovation Project(2010484)National Natural Science Foundation of China(41201432)~~
文摘Evapotranspiration ratio of six major forest types in the Pearl River Delta was studied in this paper, and the six forest types included eucalyptus forest, fruit forest, coniferous forest, shrub forest, coniferous forest, and broad-leaved mixed for- est. The mechanism of PT-T model was analyzed based on Priestley-Taylor ex- tended model, and the result showed that land surface temperature or temperature difference between day and night could be used to evaluate the evapotranspiration factor. The evapotranspiration of 6 forest types was estimated with MODIS data and TM data and weather information during 2008-2009. The result suggested that water consumption of different forest differs insignificantly, and the EF of eucalyptus is not high.
