During the 1950s the Hula wetlands and old lake were drained and the land converted utilization to agriculture and ecotourism. As a result of the drainage, the Peat Soil was exposed to atmospheric oxygen. The geochemi...During the 1950s the Hula wetlands and old lake were drained and the land converted utilization to agriculture and ecotourism. As a result of the drainage, the Peat Soil was exposed to atmospheric oxygen. The geochemical environment was modified from reductive to oxidative and the Nitrogen in it was converted from Ammonium to Nitrate. Intensive migration of Nitrate from the Hula Valley induced a national concern of water quality deterioration in the lake which was dissipated when Nitrogen deficiency was developed in Lake Kinneret. Forty years after drainage the ecosystem structure was renovated (Hula Project, HP) aimed at agricultural management and nutrient migration reduction. The paper examines through evaluation of the ecological data record (1993-2018) the impact of hydrological changes, attributed to the HP implementation on nutrient dynamics within surface waters in the Hula Valley. It is suggested that soil moisture elevation by irrigation in summer reduced Phosphorus and enhanced Nitrate concentrations.展开更多
The behavior of oil and water in tight rocks can change the distribution of oil or water in pores,which affects the production of crude oil.Nuclear Magnetic Resonance(NMR)method is an effective and nondestructive tool...The behavior of oil and water in tight rocks can change the distribution of oil or water in pores,which affects the production of crude oil.Nuclear Magnetic Resonance(NMR)method is an effective and nondestructive tool for evaluating rocks with comparison and analysis both quantitatively and qualitatively.In our study,20 MHz NMR Relaxometry is used as a key technique to study the changes of water and oil behaviors in Chinese lacustrine Qingshankou shales under different saturated states(imbibition and evaporation without pressure).The results show that variation in different proton populations(water,oil and organic)can be distinguished using 2D T_(1)-T_(2)maps.The comparison among T_(1)-T_(2)maps with different saturated states shows that different signal regions changed during oil and water migrations,which the 1D NMR Relaxometry may be not easy to approach.Combined with the pyrolysis analysis,T2 shift and differences of signal regions in T_(1)-T_(2)maps can reflect properties such as wettability and composition(organic matter,clay and magnetic minerals)to some extent.This study provides better insight into oil and water behaviors in lacustrine oil shales with further understanding of 20 MHz NMR 2D T_(1)-T_(2)maps both in qualitative and quantitative analysis.展开更多
Fuel accumulation, mainly as fatty acids, is one of the main characteristics of migratory, birds. Studying to what extent each population or species manages fuel load and how it varies along routes of migration or bet...Fuel accumulation, mainly as fatty acids, is one of the main characteristics of migratory, birds. Studying to what extent each population or species manages fuel load and how it varies along routes of migration or between seasons （autumn and spring migrations） is crucial to our understanding of bird migration strategies. Our aim here was to analyse whether migratory blackcaps Sylvia atrieapilla passing through northern Iberia differ in their mean fuel loads, rate of fuel accumulation and ＇ potential＇ flight ranges between migration seasons. Blackcaps were mist netted for 4 h-periods beginning at dawn from 16 September to 15 November 2003 - 2005, and from 1 March to 30 April 2004 - 2006 in a European Atlantic hedgerow at Loza, northern Iberia. Both fuel load and fuel deposition rate （this latter assessed with difference in body mass of within-season recaptured individuals） were higher in autumn than in spring. Possible hypotheses explaining these results could be seasonal-associated variations in food availability （likely lower during spring than during autumn）, the fact that a fraction of the migrants captured in spring could breed close to the study area and different selective pressures for breeding and wintering展开更多
Mass aggregations and migrations of millipedes despite numerous attempts to find causes for their occurrences are still an enigma. They have been reported from both southern and northern hemisphere countries, from hig...Mass aggregations and migrations of millipedes despite numerous attempts to find causes for their occurrences are still an enigma. They have been reported from both southern and northern hemisphere countries, from highlands and lowlands of both tropical and temperate regions and they can involve species belonging to the orders Julida and Spirobolida, Polydesmida and Glomerida. According to the main suggestions put forward in the past, mass occurrences in Diplopoda occur：（1） because of a lack of food and a population increase beyond sustainable levels;（2） for the purpose of reproduction and in order to locate suitable oviposition sites;（3） to find overwintering or aestivation sites;（4） because of habitat disruption and changes in the local environment;（5） as a consequence of weather conditions the year（or winter and spring） before. A recent outbreak（November 2014） of a mass migration of the polydesmid Chamberlinius hualienensis Wang 1956 on the Japanese Izu Island of Hachijojima 300 km to the south of Tokyo gave this author an opportunity to review the existing literature on millipede mass migrations and to carry out additional observations on the phenomenon in the field as well as the laboratory. Hitherto unreported heavy infestations with phoretic deutonymphs of the mite Histiostoma sp. as well as dense populations of internal rhabditid nematodes（Oscheius cf. necromena and an unidentified species of the genus Fictor）, suggest that infestations of this kind could be necromenic and either have been a contributing factor for the mass migration or been a consequence of so manyindividuals occurring together at close proximity. It is concluded that mass migrations and aggregations in millipedes do not have one common cause, but represent phenomena that often are seasonally recurring events and appear identical in their outcome, but which have evolved as responses to different causes in different millipede taxa and therefore need to be examined on a case-to-case basis.展开更多
IT infrastructures have been widely deployed in datacentres by cloud service providers for Infrastructure as a Service (IaaS) with Virtual Machines (VMs). With the rapid development of cloud-based tools and techniques...IT infrastructures have been widely deployed in datacentres by cloud service providers for Infrastructure as a Service (IaaS) with Virtual Machines (VMs). With the rapid development of cloud-based tools and techniques, IaaS is changing the current cloud infrastructure to meet the customer demand. In this paper, an efficient management model is presented and evaluated using our unique Trans-Atlantic high-speed optical fibre network connecting three datacentres located in Coleraine (Northern Ireland), Dublin (Ireland) and Halifax (Canada). Our work highlights the design and implementation of a management system that can dynamically create VMs upon request, process live migration and other services over the high-speed inter-networking Datacentres (DCs). The goal is to provide an efficient and intelligent on-demand management system for virtualization that can make decisions about the migration of VMs and get better utilisation of the network.展开更多
Mobile agents are able to migrate among machines to achieve their tasks. This feature is attractive to design, implement, and maintain distributed systems because we can implement both client-side and server-side prog...Mobile agents are able to migrate among machines to achieve their tasks. This feature is attractive to design, implement, and maintain distributed systems because we can implement both client-side and server-side programming in one mobile agent. However, it involves the increase of data traffic for mobile agent migrations. In this paper, we propose program code caching to reduce the data traffic caused by mobile agent migrations. A mobile agent consists of many program codes that define a task executed in each machine they migrate; thus, the mobile agent migration involves the transfer of their program codes. Therefore, our method reduces the number of the transfer of program codes by using program code cache. We have implemented our method on a mobile agent framework called Maglog and conducted experiments on a meeting scheduling system.展开更多
Herein,we report a distinctive and marvelous dual-migration of alkynyl tetracoordinate borons activated by both hydrochloric acid(HCl)and N-chlorosuccinimide(NCS),which is significantly different from conventional mig...Herein,we report a distinctive and marvelous dual-migration of alkynyl tetracoordinate borons activated by both hydrochloric acid(HCl)and N-chlorosuccinimide(NCS),which is significantly different from conventional migration modes under basic conditions.In this protocol,HCl,as the first electrophile,activates the C≡C bond,triggering the first 1,2-aryl migration.Subsequently,NCS promotes a secondary metallate shift,enabling the construction of polysubstituted alkenes.Notably,this process can work well under mild conditions,exhibits high efficiency,and provides valuable products.This transformation reveals that Zweifel olefination is not just limited to traditional basic conditions,it can proceed smoothly under acidic conditions as well,which greatly expands the scope of this well-known olefination reaction.展开更多
Photocatalyzed alkylsulfonylation of unactivated alkenes using DABCO.(SO_(2))_(2) and thianthrenium salts via a distal heteroaryl migration process has been developed,which provides a new means of synthesizing a varie...Photocatalyzed alkylsulfonylation of unactivated alkenes using DABCO.(SO_(2))_(2) and thianthrenium salts via a distal heteroaryl migration process has been developed,which provides a new means of synthesizing a variety of valuable alkylsulfonyl-substituted compounds.These alkylsulfonyl radicals couple with unactivated alkenes to undergo efficient intermolecular reactions,followed by distal heteroaryl migration.This mild catalytic method is tolerant of functional groups and affords medicinally relevant alkylsulfonylated heterocycles.展开更多
Internal migration motivated by access to higher education is a relatively unexplored topic in Colombia,leading to a lack of data on its dimensions,characteristics,and impacts on urban space and the emotional conditio...Internal migration motivated by access to higher education is a relatively unexplored topic in Colombia,leading to a lack of data on its dimensions,characteristics,and impacts on urban space and the emotional conditions of migrants.For this reason,an academic program of architecture in a public university was selected to comprehend the internal migrations of students,exploring their territorial experiences,living conditions,and social mobility capacity.An exploratory methodology was designed to recognize the phenomenon through a descriptive analysis,utilizing institutional data,surveys,and interviews.The research identifies the primary reasons,barriers,and impacts experienced by the migrant population in Ibagué,Colombia.The study concludes with recommendations pertaining to both institutional and urban planning to address these identified challenges.展开更多
There’s a popular saying that captures the deep and heartfelt connection between China and Thailand:“China and Thailand are not strangers,but brothers”—or in Chinese,“中泰一家亲.”This phrase is more than just a ...There’s a popular saying that captures the deep and heartfelt connection between China and Thailand:“China and Thailand are not strangers,but brothers”—or in Chinese,“中泰一家亲.”This phrase is more than just a charming proverb.It reflects centuries of migration,shared traditions,and growing goodwill between two nations whose relationship has matured into one of the most enduring and peoplecentered partnerships in Asia.展开更多
In mid-June,the vast,rolling meadow steppe grasslands of Bayanwenduer Sumu in Ar Horqin Banner,Inner Mongolia Autonomous Region,once again stretched into the horizon like green waves with herds of cattle and sheep sca...In mid-June,the vast,rolling meadow steppe grasslands of Bayanwenduer Sumu in Ar Horqin Banner,Inner Mongolia Autonomous Region,once again stretched into the horizon like green waves with herds of cattle and sheep scattered across them like pearls in a green ocean.This flock was driven by herders on horseback,motorcycles,and agricultural vehicles,leading the animals to summer pastures in one of the most important migrations of the year.展开更多
This book offers a rare window into the Serengeti through the eyes of famed zoologist Anthony Sinclair,whose five decades of research helped to unlock the secrets of this unparalleled ecosystem.Known worldwide for its...This book offers a rare window into the Serengeti through the eyes of famed zoologist Anthony Sinclair,whose five decades of research helped to unlock the secrets of this unparalleled ecosystem.Known worldwide for its breath-taking animal migrations,astonishing biodiversity,and sheer scale of life on the move,the Serengeti has long fascinated both travellers and scientists.展开更多
Schwann cell transplantation is considered one of the most promising cell-based therapy to repair injured spinal cord due to its unique growth-promoting and myelin-forming properties.A the Food and Drug Administration...Schwann cell transplantation is considered one of the most promising cell-based therapy to repair injured spinal cord due to its unique growth-promoting and myelin-forming properties.A the Food and Drug Administration-approved Phase I clinical trial has been conducted to evaluate the safety of transplanted human autologous Schwann cells to treat patients with spinal cord injury.A major challenge for Schwann cell transplantation is that grafted Schwann cells are confined within the lesion cavity,and they do not migrate into the host environment due to the inhibitory barrier formed by injury-induced glial scar,thus limiting axonal reentry into the host spinal cord.Here we introduce a combinatorial strategy by suppressing the inhibitory extracellular environment with injection of lentivirus-mediated transfection of chondroitinase ABC gene at the rostral and caudal borders of the lesion site and simultaneously leveraging the repair capacity of transplanted Schwann cells in adult rats following a mid-thoracic contusive spinal cord injury.We report that when the glial scar was degraded by chondroitinase ABC at the rostral and caudal lesion borders,Schwann cells migrated for considerable distances in both rostral and caudal directions.Such Schwann cell migration led to enhanced axonal regrowth,including the serotonergic and dopaminergic axons originating from supraspinal regions,and promoted recovery of locomotor and urinary bladder functions.Importantly,the Schwann cell survival and axonal regrowth persisted up to 6 months after the injury,even when treatment was delayed for 3 months to mimic chronic spinal cord injury.These findings collectively show promising evidence for a combinatorial strategy with chondroitinase ABC and Schwann cells in promoting remodeling and recovery of function following spinal cord injury.展开更多
BACKGROUND The objective of the current study was to elucidate the clinical mechanism through which phospholipase D2(PLD2)exerted a regulatory effect on neutrophil migra-tion,thereby alleviating the progression of acu...BACKGROUND The objective of the current study was to elucidate the clinical mechanism through which phospholipase D2(PLD2)exerted a regulatory effect on neutrophil migra-tion,thereby alleviating the progression of acute pancreatitis.AIM To elucidate the clinical mechanism through which PLD2 exerted a regulatory effect on neutrophil migration,thereby alleviating the progression of acute pan-creatitis.METHODS The study involved 90 patients diagnosed with acute pancreatitis,admitted to our hospital between March 2020 and November 2022.A retrospective analysis was conducted,categorizing patients based on Ranson score severity into mild(n=25),moderate(n=30),and severe(n=35)groups.Relevant data was collected for each group.Western blot analysis assessed PLD2 protein expression in patient serum.Real-time reverse transcription polymerase chain reaction was used to evaluate the mRNA expression of chemokine receptors associated with neutrophil migration.Serum levels of inflammatory factors in patients were detected using enzyme-linked immunosorbent assay.Transwell migration tests were conducted to compare migration of neutrophils across groups and analyze the influence of PLD2 on neutrophil migration.RESULTS Overall data analysis did not find significant differences between patient groups(P>0.05).The expression of PLD2 protein in the severe group was lower than that in the moderate and mild groups(P<0.05).The expression level of PLD2 in the moderate group was also lower than that in the mild group(P<0.05).The severity of acute pancreatitis is negatively correlated with PLD2 expression(r=-0.75,P=0.002).The mRNA levels of C-X-C chemokine receptor type 1,C-X-C chemokine receptor type 2,C-C chemokine receptor type 2,and C-C chemokine receptor type 5 in the severe group are significantly higher than those in the moderate and mild groups(P<0.05),and the expression levels in the moderate group are also higher than those in the mild group(P<0.05).The levels of C-reactive protein,tumor necrosis factor-α,interleukin-1β,and interleukin-6 in the severe group were higher than those in the moderate and mild groups(P<0.05),and the levels in the moderate group were also higher than those in the mild group(P<0.05).The number of migrating neutrophils in the severe group was higher than that in the moderate and mild groups(P<0.05),and the moderate group was also higher than the mild group(P<0.05).In addition,the number of migrating neutrophils in the mild group combined with PLD2 inhibitor was higher than that in the mild group(P<0.05),and the number of migrating neutrophils in the moderate group combined with PLD2 inhibitor was higher than that in the moderate group(P<0.05).The number of migrating neutrophils in the severe group+PLD2 inhibitor group was significantly higher than that in the severe group(P<0.05),indicating that PLD2 inhibitors significantly stimulated neutrophil migration.CONCLUSION PLD2 exerted a crucial regulatory role in the pathological progression of acute pancreatitis.Its protein expression varied among patients based on the severity of the disease,and a negative correlation existed between PLD2 expression and disease severity.Additionally,PLD2 appeared to impede acute pancreatitis progression by limiting neutrophil migration.展开更多
Perovskite quantum dot light-emitting diodes(Pe-QLEDs)have shown immense application potential in display and lighting fields due to their narrow full-width at half maximum(FWHM)and high photoluminescence quantum yiel...Perovskite quantum dot light-emitting diodes(Pe-QLEDs)have shown immense application potential in display and lighting fields due to their narrow full-width at half maximum(FWHM)and high photoluminescence quantum yield(PLQY).Despite significant advancements in their performance,challenges such as defects and ion migration still hinder their long-term stability and operational efficiency.To address these issues,various optimization strategies,including ligand engineering,interface passivation,and self-assembly strategy,are being actively researched.This review focuses on the synthesis methods,challenges and optimization of perovskite quantum dots,which are critical for the commercialization and large-scale production of high-performance and stable Pe-QLEDs.展开更多
Controlling heavy metal pollution in agricultural soil has been a significant challenge.These heavy metals seriously threaten the surrounding ecological environment and human health.The effective assessment and remedi...Controlling heavy metal pollution in agricultural soil has been a significant challenge.These heavy metals seriously threaten the surrounding ecological environment and human health.The effective assessment and remediation of heavy metals in agricultural soils are crucial.These two aspects support each other,forming a close and complete decisionmaking chain.Therefore,this review systematically summarizes the distribution characteristics of soil heavy metal pollution,the correlation between soil and crop heavy metal contents,the presence pattern and migration and transformation mode of heavy metals in the soil-crop system.The advantages and disadvantages of the risk evaluation tools and models of heavy metal pollution in farmland are further outlined,which provides important guidance for an in-depth understanding of the characteristics of heavymetal pollution in farmland soils and the assessment of the environmental risk.Soil remediation strategies involve multiple physical,chemical,biological and even combined technologies,and this paper compares the potential and effect of the above current remediation technologies in heavy metal polluted farmland soils.Finally,the main problems and possible research directions of future heavy metal risk assessment and remediation technologies in agricultural soils are prospected.This review provides new ideas for effective assessment and selection of remediation technologies based on the characterization of soil heavy metals.展开更多
The Qinghai-Tibet Plateau,with its high altitude and cold climate,is one of the most fragile ecological environments in China and is distinguished by its naturally elevated arsenic(As)levels in the soil,largely due to...The Qinghai-Tibet Plateau,with its high altitude and cold climate,is one of the most fragile ecological environments in China and is distinguished by its naturally elevated arsenic(As)levels in the soil,largely due to its rich mineral and geothermal resources.This review provides a comprehensive analysis of As content,focusing on its distribution,environmental migration,and transformation behavior across the plateau.The review further evaluates the distribution of As in different functional areas,revealing that geothermal fields(107.2 mg/kg),mining areas(53.8 mg/kg),and croplands(39.3 mg/kg)have the highest As concentrations,followed by river and lake sediments and adjacent areas(33.1 mg/kg).These elevated levels are primarily attributed to the presence of As-rich minerals,such as arsenopyrite and pyrite.Additionally,human activities,including mining and geothermal energy production,exacerbate the release of As into the environment.The review also highlights the role of localmicroorganisms,particularly those fromthe phyla Proteobacteria and Actinobacteria,which possess As metabolic genes that facilitate As translocation.Given the unique climatic conditions of the plateau,conventionalmethods for As controlmay not be fully effective.However,the review identifies promising remediation strategies that are environmentally adaptable,such as the use of local microorganisms,specific adsorbents,and integrated technologies,which offer potential solutions for managing and utilizing Ascontaminated soils on the plateau.展开更多
The traditional von Neumann architecture faces inherent limitations due to the separation of memory and computa-tion,leading to high energy consumption,significant latency,and reduced operational efficiency.Neuromorph...The traditional von Neumann architecture faces inherent limitations due to the separation of memory and computa-tion,leading to high energy consumption,significant latency,and reduced operational efficiency.Neuromorphic computing,inspired by the architecture of the human brain,offers a promising alternative by integrating memory and computational func-tions,enabling parallel,high-speed,and energy-efficient information processing.Among various neuromorphic technologies,ion-modulated optoelectronic devices have garnered attention due to their excellent ionic tunability and the availability of multi-dimensional control strategies.This review provides a comprehensive overview of recent progress in ion-modulation optoelec-tronic neuromorphic devices.It elucidates the key mechanisms underlying ionic modulation of light fields,including ion migra-tion dynamics and capture and release of charge through ions.Furthermore,the synthesis of active materials and the proper-ties of these devices are analyzed in detail.The review also highlights the application of ion-modulation optoelectronic devices in artificial vision systems,neuromorphic computing,and other bionic fields.Finally,the existing challenges and future direc-tions for the development of optoelectronic neuromorphic devices are discussed,providing critical insights for advancing this promising field.展开更多
Through strategies such as process optimization,solvent selection,and component tuning,the crystallization of perovskite materials has been effectively controlled,enabling perovskite solar cells(PSCs)to achieve over 2...Through strategies such as process optimization,solvent selection,and component tuning,the crystallization of perovskite materials has been effectively controlled,enabling perovskite solar cells(PSCs)to achieve over 25%power conversion efficiency(PCE).However,as PCE continues to improve,interfacial issues within the devices have emerged as critical bottlenecks,hindering further performance enhancements.Recently,interfacial engineering has driven transformative progress,pushing PCEs to nearly 27%.Building upon these developments,this review first summarizes the pivotal role of interfacial modifications in elevating device performance and then,as a starting point,provides a comprehensive overview of recent advancements in normal,inverted,and tandem structure devices.Finally,based on the current progress of PSCs,preliminary perspectives on future directions are presented.展开更多
文摘During the 1950s the Hula wetlands and old lake were drained and the land converted utilization to agriculture and ecotourism. As a result of the drainage, the Peat Soil was exposed to atmospheric oxygen. The geochemical environment was modified from reductive to oxidative and the Nitrogen in it was converted from Ammonium to Nitrate. Intensive migration of Nitrate from the Hula Valley induced a national concern of water quality deterioration in the lake which was dissipated when Nitrogen deficiency was developed in Lake Kinneret. Forty years after drainage the ecosystem structure was renovated (Hula Project, HP) aimed at agricultural management and nutrient migration reduction. The paper examines through evaluation of the ecological data record (1993-2018) the impact of hydrological changes, attributed to the HP implementation on nutrient dynamics within surface waters in the Hula Valley. It is suggested that soil moisture elevation by irrigation in summer reduced Phosphorus and enhanced Nitrate concentrations.
基金supported by the Opening Fund of Key Laboratory of Continental Shale Accumulation and Development(Northeast Petroleum University,China)the National Natural Science Foundation of China(Grant No.51605089,Grant No.41972156)
文摘The behavior of oil and water in tight rocks can change the distribution of oil or water in pores,which affects the production of crude oil.Nuclear Magnetic Resonance(NMR)method is an effective and nondestructive tool for evaluating rocks with comparison and analysis both quantitatively and qualitatively.In our study,20 MHz NMR Relaxometry is used as a key technique to study the changes of water and oil behaviors in Chinese lacustrine Qingshankou shales under different saturated states(imbibition and evaporation without pressure).The results show that variation in different proton populations(water,oil and organic)can be distinguished using 2D T_(1)-T_(2)maps.The comparison among T_(1)-T_(2)maps with different saturated states shows that different signal regions changed during oil and water migrations,which the 1D NMR Relaxometry may be not easy to approach.Combined with the pyrolysis analysis,T2 shift and differences of signal regions in T_(1)-T_(2)maps can reflect properties such as wettability and composition(organic matter,clay and magnetic minerals)to some extent.This study provides better insight into oil and water behaviors in lacustrine oil shales with further understanding of 20 MHz NMR 2D T_(1)-T_(2)maps both in qualitative and quantitative analysis.
基金supported by a postgraduate fellowship from the Basque Governmentsupported by project CGL2007-61395(Ministry of Education and Science,Government of Spain)
文摘Fuel accumulation, mainly as fatty acids, is one of the main characteristics of migratory, birds. Studying to what extent each population or species manages fuel load and how it varies along routes of migration or between seasons （autumn and spring migrations） is crucial to our understanding of bird migration strategies. Our aim here was to analyse whether migratory blackcaps Sylvia atrieapilla passing through northern Iberia differ in their mean fuel loads, rate of fuel accumulation and ＇ potential＇ flight ranges between migration seasons. Blackcaps were mist netted for 4 h-periods beginning at dawn from 16 September to 15 November 2003 - 2005, and from 1 March to 30 April 2004 - 2006 in a European Atlantic hedgerow at Loza, northern Iberia. Both fuel load and fuel deposition rate （this latter assessed with difference in body mass of within-season recaptured individuals） were higher in autumn than in spring. Possible hypotheses explaining these results could be seasonal-associated variations in food availability （likely lower during spring than during autumn）, the fact that a fraction of the migrants captured in spring could breed close to the study area and different selective pressures for breeding and wintering
文摘Mass aggregations and migrations of millipedes despite numerous attempts to find causes for their occurrences are still an enigma. They have been reported from both southern and northern hemisphere countries, from highlands and lowlands of both tropical and temperate regions and they can involve species belonging to the orders Julida and Spirobolida, Polydesmida and Glomerida. According to the main suggestions put forward in the past, mass occurrences in Diplopoda occur：（1） because of a lack of food and a population increase beyond sustainable levels;（2） for the purpose of reproduction and in order to locate suitable oviposition sites;（3） to find overwintering or aestivation sites;（4） because of habitat disruption and changes in the local environment;（5） as a consequence of weather conditions the year（or winter and spring） before. A recent outbreak（November 2014） of a mass migration of the polydesmid Chamberlinius hualienensis Wang 1956 on the Japanese Izu Island of Hachijojima 300 km to the south of Tokyo gave this author an opportunity to review the existing literature on millipede mass migrations and to carry out additional observations on the phenomenon in the field as well as the laboratory. Hitherto unreported heavy infestations with phoretic deutonymphs of the mite Histiostoma sp. as well as dense populations of internal rhabditid nematodes（Oscheius cf. necromena and an unidentified species of the genus Fictor）, suggest that infestations of this kind could be necromenic and either have been a contributing factor for the mass migration or been a consequence of so manyindividuals occurring together at close proximity. It is concluded that mass migrations and aggregations in millipedes do not have one common cause, but represent phenomena that often are seasonally recurring events and appear identical in their outcome, but which have evolved as responses to different causes in different millipede taxa and therefore need to be examined on a case-to-case basis.
文摘IT infrastructures have been widely deployed in datacentres by cloud service providers for Infrastructure as a Service (IaaS) with Virtual Machines (VMs). With the rapid development of cloud-based tools and techniques, IaaS is changing the current cloud infrastructure to meet the customer demand. In this paper, an efficient management model is presented and evaluated using our unique Trans-Atlantic high-speed optical fibre network connecting three datacentres located in Coleraine (Northern Ireland), Dublin (Ireland) and Halifax (Canada). Our work highlights the design and implementation of a management system that can dynamically create VMs upon request, process live migration and other services over the high-speed inter-networking Datacentres (DCs). The goal is to provide an efficient and intelligent on-demand management system for virtualization that can make decisions about the migration of VMs and get better utilisation of the network.
文摘Mobile agents are able to migrate among machines to achieve their tasks. This feature is attractive to design, implement, and maintain distributed systems because we can implement both client-side and server-side programming in one mobile agent. However, it involves the increase of data traffic for mobile agent migrations. In this paper, we propose program code caching to reduce the data traffic caused by mobile agent migrations. A mobile agent consists of many program codes that define a task executed in each machine they migrate; thus, the mobile agent migration involves the transfer of their program codes. Therefore, our method reduces the number of the transfer of program codes by using program code cache. We have implemented our method on a mobile agent framework called Maglog and conducted experiments on a meeting scheduling system.
基金the financial support from the National Key Research&Development Program of China(2023YFF0723900)the National Natural Science Foundation of China(22271105)+3 种基金the Natural Science Foundation of Fujian Province(2022J02009)the Open Research Fund of State Key Laboratory of Coordination ChemistrySchool of Chemistry and Chemical Engineering,Nanjing Universitythe Hubei Key Laboratory of Pollutant Analysis&Reuse Technology Open Foundation(PA240102)。
文摘Herein,we report a distinctive and marvelous dual-migration of alkynyl tetracoordinate borons activated by both hydrochloric acid(HCl)and N-chlorosuccinimide(NCS),which is significantly different from conventional migration modes under basic conditions.In this protocol,HCl,as the first electrophile,activates the C≡C bond,triggering the first 1,2-aryl migration.Subsequently,NCS promotes a secondary metallate shift,enabling the construction of polysubstituted alkenes.Notably,this process can work well under mild conditions,exhibits high efficiency,and provides valuable products.This transformation reveals that Zweifel olefination is not just limited to traditional basic conditions,it can proceed smoothly under acidic conditions as well,which greatly expands the scope of this well-known olefination reaction.
基金the National Natural Science Foundation of China(Nos.21702103 and 21522604)the Jiangsu Synergetic Innovation Center for Advanced Bio-Manufacture(No.XTD2203)+1 种基金the Natural Science Research Projects of Jiangsu Higher Education(No.19KJB150027)Jiangsu Funding Program for Excellent Postdoctoral Talent(No.2022ZB389).
文摘Photocatalyzed alkylsulfonylation of unactivated alkenes using DABCO.(SO_(2))_(2) and thianthrenium salts via a distal heteroaryl migration process has been developed,which provides a new means of synthesizing a variety of valuable alkylsulfonyl-substituted compounds.These alkylsulfonyl radicals couple with unactivated alkenes to undergo efficient intermolecular reactions,followed by distal heteroaryl migration.This mild catalytic method is tolerant of functional groups and affords medicinally relevant alkylsulfonylated heterocycles.
文摘Internal migration motivated by access to higher education is a relatively unexplored topic in Colombia,leading to a lack of data on its dimensions,characteristics,and impacts on urban space and the emotional conditions of migrants.For this reason,an academic program of architecture in a public university was selected to comprehend the internal migrations of students,exploring their territorial experiences,living conditions,and social mobility capacity.An exploratory methodology was designed to recognize the phenomenon through a descriptive analysis,utilizing institutional data,surveys,and interviews.The research identifies the primary reasons,barriers,and impacts experienced by the migrant population in Ibagué,Colombia.The study concludes with recommendations pertaining to both institutional and urban planning to address these identified challenges.
文摘There’s a popular saying that captures the deep and heartfelt connection between China and Thailand:“China and Thailand are not strangers,but brothers”—or in Chinese,“中泰一家亲.”This phrase is more than just a charming proverb.It reflects centuries of migration,shared traditions,and growing goodwill between two nations whose relationship has matured into one of the most enduring and peoplecentered partnerships in Asia.
文摘In mid-June,the vast,rolling meadow steppe grasslands of Bayanwenduer Sumu in Ar Horqin Banner,Inner Mongolia Autonomous Region,once again stretched into the horizon like green waves with herds of cattle and sheep scattered across them like pearls in a green ocean.This flock was driven by herders on horseback,motorcycles,and agricultural vehicles,leading the animals to summer pastures in one of the most important migrations of the year.
文摘This book offers a rare window into the Serengeti through the eyes of famed zoologist Anthony Sinclair,whose five decades of research helped to unlock the secrets of this unparalleled ecosystem.Known worldwide for its breath-taking animal migrations,astonishing biodiversity,and sheer scale of life on the move,the Serengeti has long fascinated both travellers and scientists.
基金supported in part by NIH R01 NS100531,R01 NS103481NIH R21NS130241(to LD)+3 种基金Merit Review Award I01 BX002356,I01 BX003705 from the U.S.Department of Veterans AffairsIndiana Spinal Cord and Brain Injury Research Foundation(No.19919)Mari Hulman George Endowment Funds(to XMX)Indiana Spinal Cord&Brain Injury Research Fund from ISDH(to NKL and LD)。
文摘Schwann cell transplantation is considered one of the most promising cell-based therapy to repair injured spinal cord due to its unique growth-promoting and myelin-forming properties.A the Food and Drug Administration-approved Phase I clinical trial has been conducted to evaluate the safety of transplanted human autologous Schwann cells to treat patients with spinal cord injury.A major challenge for Schwann cell transplantation is that grafted Schwann cells are confined within the lesion cavity,and they do not migrate into the host environment due to the inhibitory barrier formed by injury-induced glial scar,thus limiting axonal reentry into the host spinal cord.Here we introduce a combinatorial strategy by suppressing the inhibitory extracellular environment with injection of lentivirus-mediated transfection of chondroitinase ABC gene at the rostral and caudal borders of the lesion site and simultaneously leveraging the repair capacity of transplanted Schwann cells in adult rats following a mid-thoracic contusive spinal cord injury.We report that when the glial scar was degraded by chondroitinase ABC at the rostral and caudal lesion borders,Schwann cells migrated for considerable distances in both rostral and caudal directions.Such Schwann cell migration led to enhanced axonal regrowth,including the serotonergic and dopaminergic axons originating from supraspinal regions,and promoted recovery of locomotor and urinary bladder functions.Importantly,the Schwann cell survival and axonal regrowth persisted up to 6 months after the injury,even when treatment was delayed for 3 months to mimic chronic spinal cord injury.These findings collectively show promising evidence for a combinatorial strategy with chondroitinase ABC and Schwann cells in promoting remodeling and recovery of function following spinal cord injury.
文摘BACKGROUND The objective of the current study was to elucidate the clinical mechanism through which phospholipase D2(PLD2)exerted a regulatory effect on neutrophil migra-tion,thereby alleviating the progression of acute pancreatitis.AIM To elucidate the clinical mechanism through which PLD2 exerted a regulatory effect on neutrophil migration,thereby alleviating the progression of acute pan-creatitis.METHODS The study involved 90 patients diagnosed with acute pancreatitis,admitted to our hospital between March 2020 and November 2022.A retrospective analysis was conducted,categorizing patients based on Ranson score severity into mild(n=25),moderate(n=30),and severe(n=35)groups.Relevant data was collected for each group.Western blot analysis assessed PLD2 protein expression in patient serum.Real-time reverse transcription polymerase chain reaction was used to evaluate the mRNA expression of chemokine receptors associated with neutrophil migration.Serum levels of inflammatory factors in patients were detected using enzyme-linked immunosorbent assay.Transwell migration tests were conducted to compare migration of neutrophils across groups and analyze the influence of PLD2 on neutrophil migration.RESULTS Overall data analysis did not find significant differences between patient groups(P>0.05).The expression of PLD2 protein in the severe group was lower than that in the moderate and mild groups(P<0.05).The expression level of PLD2 in the moderate group was also lower than that in the mild group(P<0.05).The severity of acute pancreatitis is negatively correlated with PLD2 expression(r=-0.75,P=0.002).The mRNA levels of C-X-C chemokine receptor type 1,C-X-C chemokine receptor type 2,C-C chemokine receptor type 2,and C-C chemokine receptor type 5 in the severe group are significantly higher than those in the moderate and mild groups(P<0.05),and the expression levels in the moderate group are also higher than those in the mild group(P<0.05).The levels of C-reactive protein,tumor necrosis factor-α,interleukin-1β,and interleukin-6 in the severe group were higher than those in the moderate and mild groups(P<0.05),and the levels in the moderate group were also higher than those in the mild group(P<0.05).The number of migrating neutrophils in the severe group was higher than that in the moderate and mild groups(P<0.05),and the moderate group was also higher than the mild group(P<0.05).In addition,the number of migrating neutrophils in the mild group combined with PLD2 inhibitor was higher than that in the mild group(P<0.05),and the number of migrating neutrophils in the moderate group combined with PLD2 inhibitor was higher than that in the moderate group(P<0.05).The number of migrating neutrophils in the severe group+PLD2 inhibitor group was significantly higher than that in the severe group(P<0.05),indicating that PLD2 inhibitors significantly stimulated neutrophil migration.CONCLUSION PLD2 exerted a crucial regulatory role in the pathological progression of acute pancreatitis.Its protein expression varied among patients based on the severity of the disease,and a negative correlation existed between PLD2 expression and disease severity.Additionally,PLD2 appeared to impede acute pancreatitis progression by limiting neutrophil migration.
文摘Perovskite quantum dot light-emitting diodes(Pe-QLEDs)have shown immense application potential in display and lighting fields due to their narrow full-width at half maximum(FWHM)and high photoluminescence quantum yield(PLQY).Despite significant advancements in their performance,challenges such as defects and ion migration still hinder their long-term stability and operational efficiency.To address these issues,various optimization strategies,including ligand engineering,interface passivation,and self-assembly strategy,are being actively researched.This review focuses on the synthesis methods,challenges and optimization of perovskite quantum dots,which are critical for the commercialization and large-scale production of high-performance and stable Pe-QLEDs.
基金supported by the National Natural Science Foundation of China(Nos.52100184,and U22A20617).
文摘Controlling heavy metal pollution in agricultural soil has been a significant challenge.These heavy metals seriously threaten the surrounding ecological environment and human health.The effective assessment and remediation of heavy metals in agricultural soils are crucial.These two aspects support each other,forming a close and complete decisionmaking chain.Therefore,this review systematically summarizes the distribution characteristics of soil heavy metal pollution,the correlation between soil and crop heavy metal contents,the presence pattern and migration and transformation mode of heavy metals in the soil-crop system.The advantages and disadvantages of the risk evaluation tools and models of heavy metal pollution in farmland are further outlined,which provides important guidance for an in-depth understanding of the characteristics of heavymetal pollution in farmland soils and the assessment of the environmental risk.Soil remediation strategies involve multiple physical,chemical,biological and even combined technologies,and this paper compares the potential and effect of the above current remediation technologies in heavy metal polluted farmland soils.Finally,the main problems and possible research directions of future heavy metal risk assessment and remediation technologies in agricultural soils are prospected.This review provides new ideas for effective assessment and selection of remediation technologies based on the characterization of soil heavy metals.
基金supported by the Central Public-interest Scientific Institution Basal Research Fund(No.Y2024QC29)the Central Public-interest Scientific Institution Basal Research Fund(Nos.2024-jbkyywf-lwj and 2024-jbkyywf-zyj).
文摘The Qinghai-Tibet Plateau,with its high altitude and cold climate,is one of the most fragile ecological environments in China and is distinguished by its naturally elevated arsenic(As)levels in the soil,largely due to its rich mineral and geothermal resources.This review provides a comprehensive analysis of As content,focusing on its distribution,environmental migration,and transformation behavior across the plateau.The review further evaluates the distribution of As in different functional areas,revealing that geothermal fields(107.2 mg/kg),mining areas(53.8 mg/kg),and croplands(39.3 mg/kg)have the highest As concentrations,followed by river and lake sediments and adjacent areas(33.1 mg/kg).These elevated levels are primarily attributed to the presence of As-rich minerals,such as arsenopyrite and pyrite.Additionally,human activities,including mining and geothermal energy production,exacerbate the release of As into the environment.The review also highlights the role of localmicroorganisms,particularly those fromthe phyla Proteobacteria and Actinobacteria,which possess As metabolic genes that facilitate As translocation.Given the unique climatic conditions of the plateau,conventionalmethods for As controlmay not be fully effective.However,the review identifies promising remediation strategies that are environmentally adaptable,such as the use of local microorganisms,specific adsorbents,and integrated technologies,which offer potential solutions for managing and utilizing Ascontaminated soils on the plateau.
基金supported by National Natural Science Foundation of China(62174164,U23A20568,and U22A2075)National Key Research and Development Project(2021YFA1202600)+2 种基金Talent Plan of Shanghai Branch,Chinese Academy of Sciences(CASSHB-QNPD-2023-022)Ningbo Technology Project(2022A-007-C)Ningbo Key Research and Development Project(2023Z021).
文摘The traditional von Neumann architecture faces inherent limitations due to the separation of memory and computa-tion,leading to high energy consumption,significant latency,and reduced operational efficiency.Neuromorphic computing,inspired by the architecture of the human brain,offers a promising alternative by integrating memory and computational func-tions,enabling parallel,high-speed,and energy-efficient information processing.Among various neuromorphic technologies,ion-modulated optoelectronic devices have garnered attention due to their excellent ionic tunability and the availability of multi-dimensional control strategies.This review provides a comprehensive overview of recent progress in ion-modulation optoelec-tronic neuromorphic devices.It elucidates the key mechanisms underlying ionic modulation of light fields,including ion migra-tion dynamics and capture and release of charge through ions.Furthermore,the synthesis of active materials and the proper-ties of these devices are analyzed in detail.The review also highlights the application of ion-modulation optoelectronic devices in artificial vision systems,neuromorphic computing,and other bionic fields.Finally,the existing challenges and future direc-tions for the development of optoelectronic neuromorphic devices are discussed,providing critical insights for advancing this promising field.
基金supported by National Natural Science Foundation of China(52302229,62404072)the Key Lab of Modern Optical Technologies of Education Ministry of China,Soochow University(KJS2425)+1 种基金Doctoral Foundation of Henan Polytech-nic University(B2024-72)Science and Technology Research Project of Jiangxi Provincial Department of Education(Grant No.GJJ2400702).
文摘Through strategies such as process optimization,solvent selection,and component tuning,the crystallization of perovskite materials has been effectively controlled,enabling perovskite solar cells(PSCs)to achieve over 25%power conversion efficiency(PCE).However,as PCE continues to improve,interfacial issues within the devices have emerged as critical bottlenecks,hindering further performance enhancements.Recently,interfacial engineering has driven transformative progress,pushing PCEs to nearly 27%.Building upon these developments,this review first summarizes the pivotal role of interfacial modifications in elevating device performance and then,as a starting point,provides a comprehensive overview of recent advancements in normal,inverted,and tandem structure devices.Finally,based on the current progress of PSCs,preliminary perspectives on future directions are presented.
