To the Editor:Irreversible electroporation (IRE) is a CE- and FDA- approved treatment modality for pancreatic and liver tumors that is based on the site-confined destruction of tumor tissue by multiple short, high-...To the Editor:Irreversible electroporation (IRE) is a CE- and FDA- approved treatment modality for pancreatic and liver tumors that is based on the site-confined destruction of tumor tissue by multiple short, high-intensity electrical pulses.展开更多
Potential natural vegetation(PNV)is a valuable reference for ecosystem renovation and has garnered increasing attention worldwide.However,there is limited knowledge on the spatio-temporal distributions,transitional pr...Potential natural vegetation(PNV)is a valuable reference for ecosystem renovation and has garnered increasing attention worldwide.However,there is limited knowledge on the spatio-temporal distributions,transitional processes,and underlying mechanisms of global natural vegetation,particularly in the case of ongoing climate warming.In this study,we visualize the spatio-temporal pattern and inter-transition procedure of global PNV,analyse the shifting distances and directions of global PNV under the influence of climatic disturbance,and explore the mechanisms of global PNV in response to temperature and precipitation fluctuations.To achieve this,we utilize meteorological data,mainly temperature and precipitation,from six phases:the Last Inter-Glacial(LIG),the Last Glacial Maximum(LGM),the Mid Holocene(MH),the Present Day(PD),2030(20212040)and 2090(2081–2100),and employ a widely-accepted comprehensive and sequential classification sy–stem(CSCS)for global PNV classification.We find that the spatial patterns of five PNV groups(forest,shrubland,savanna,grassland and tundra)generally align with their respective ecotopes,although their distributions have shifted due to fluctuating temperature and precipitation.Notably,we observe an unexpected transition between tundra and savanna despite their geographical distance.The shifts in distance and direction of five PNV groups are mainly driven by temperature and precipitation,although there is heterogeneity among these shifts for each group.Indeed,the heterogeneity observed among different global PNV groups suggests that they may possess varying capacities to adjust to and withstand the impacts of changing climate.The spatio-temporal distributions,mutual transitions and shift tendencies of global PNV and its underlying mechanism in face of changing climate,as revealed in this study,can significantly contribute to the development of strategies for mitigating warming and promoting re-vegetation in degraded regions worldwide.展开更多
Using ground water vapor pressure and precipitation data at four times of one day during 1985- 2014 in each county( city) of Anyang,precipitable water at each station was calculated,and temporal-spatial distribution...Using ground water vapor pressure and precipitation data at four times of one day during 1985- 2014 in each county( city) of Anyang,precipitable water at each station was calculated,and temporal-spatial distribution of atmospheric maximum precipitable water and its change trend over the years in the city were analyzed. Results showed that atmospheric maximum precipitable water in Anyang City had the characteristics of summer far more than winter,autumn slightly higher than spring,west and south more,and east and north less,and presented the increasing trend year by year. We further analyzed the characteristic of monthly rainfall enhancement potential in each county,and mean in whole year was 80%. In spring and winter,rainfall enhancement potential in the west was bigger than east,while rainfall enhancement potential in the east was bigger than west in summer and autumn. The research provides reference basis for rationally carrying out artificial rainfall work,which could effectively ease uneven temporal-spatial distribution problem of water resource in Anyang City.展开更多
The southwestern depression of the Qiongdongnan Basin(QDNB)hosts thick Cenozoic sediments and awaits major hydrocarbon discovery.Multichannel seismic(MCS)profile CFT2011 across the southwestern QDNB reveals a~60-km-wi...The southwestern depression of the Qiongdongnan Basin(QDNB)hosts thick Cenozoic sediments and awaits major hydrocarbon discovery.Multichannel seismic(MCS)profile CFT2011 across the southwestern QDNB reveals a~60-km-wide fuzzy reflection zone(FRZ)within the sediments,but its origin and distribution remain unclear.Here ocean bottom seismometer(OBS)data of Line CFT2011 are processed with focus on the velocity structures by traveltime tomography inversion and analyzed together with the coincident and adjacent MCS profiles.The OBS velocity results show that the giant FRZ features lower velocity with difference up to 1.5 km/s and smaller vertical velocity gradient than the surrounding sedimentary sequences at the same depth,likely resulting from enhanced fluid infilling.The MCS profile exhibits that the giant FRZ is about 3-9-km thick and extends from the Paleogene strata rich in organic matters upward to the lower Pleistocene sediments.Within the shallow overlying sediments,multiple bright spots with reverse polarity are imaged and their reflection amplitudes increase with offset,consistent with the features of gas-charged sediments.They are probably shallow gas reservoirs with gases sourced from the deep FRZ.Therefore,the FRZ is proposed to be a giant gas-charged zone,which probably contains lots of hydrocarbon gases migrated vertically from the deep Paleogene source rocks through the boundary faults of the depressions and the minor fractures generated under overpressure.This FRZ is also imaged on the adjacent MCS profiles MCS-L1 and MCS-L2 with the width of about 40 km and 68 km,respectively.It is roughly estimated to cover an area of~1900 km2 and host a volume of~11400 km3 assuming an average thickness of 6 km,implying huge natural gas potential in the sedimentary depression of the southwestern QDNB of the South China Sea.展开更多
Since Serbia disposes with significant natural potentials, it could have been among the most attractive countries in Europe only if the historical circumstances had been different. Existing natural resources and possi...Since Serbia disposes with significant natural potentials, it could have been among the most attractive countries in Europe only if the historical circumstances had been different. Existing natural resources and possibilities for their improvement demand planned strategy to make them efficient. Tourism, as a significant instrument of development, can and should take an active part in the strategy of sustainable development. Special attention in the paper is paid to the development of Vrnjacka Banja Spa as it is one of the main tourist destinations in Serbia. The strengths, weaknesses, opportunities, and threats of a business venture (SWOT) analysis offers the basic elements for defining the strategic direction and program priorities, measures and targets for improving the overall development of spas in Serbia. To identify the SWOT factors, we used materials from a number of studies on Serbian tourism, surveys on tourists in Vrnjcka Banja Spa and analysis of the market and competition. The SWOT analysis proves that the priority in development of spas in Serbia is attractiveness of the destination which involves the spa-health tourism with great potential in complementary forms of tourism, such as sport-recreational, cultural, transit and hunting tourism. It means that the future strategy should be based on improving and involving modern spa products. It means improving and maximizing marketing so as to make the tourist destination attractive. It further implies maximum investment in modern tourist products.展开更多
Potential Natural Vegetation(PNV)represents the climax of vegetation succession in a natural environment,free from significant disturbances.The reconstruction of PNV is widely used to study climate-vegetation relation...Potential Natural Vegetation(PNV)represents the climax of vegetation succession in a natural environment,free from significant disturbances.The reconstruction of PNV is widely used to study climate-vegetation relationships and predict future vegetation distributions.However,fine-scale PNV maps with high accuracy are still rare in biodiversity hotspots due to the complexity of ecosystems and limited field observations.In this study,we mapped the spatiotemporal distribution of 16 PNV types using adequate field and literature data,and an improved Comprehensive and Sequential Classification System(CSCS)approach under current(2005-2016)and future(2021-2080)climate scenarios in Yunnan province,Southwest China.We found that 1)from T0(2005-2016)to T3(2021-2080),regions with cold alpine PNV types,such as mid-mountain humid evergreen broad-leaved forests(EBLF),are projected to experience more significant temperature increases compared to regions with warm PNV types,like tropic rainforests and monsoon rainforests.High-emission scenarios(SSP585)are expected to result in temperature increases approximately 2°C higher than low-emission scenarios(SSP126).Precipitation is projected to increase for water-deficient PNV types(e.g.,monsoon rainforest and semi-humid EBLF)but decrease for humid PNV types(e.g.,rainforest and mountain mossy EBLF).The SSP370 scenario predicts a slightly smaller increase in precipitation compared to other scenarios.2)All PNV types are expected to shift to higher latitudes(by an average of 0.86°)and higher elevations(by an average of 454 m)by T3,based on their current niches.Alpine PNV types are more sensitive to climate change and are projected to shift more prominently than other types.For example,mountain mossy EBLF is expected to move 1.78°northward,while mid-mountain moist EBLF is projected to rise by 578 m.3)Cold PNV types are likely to be replaced by warm types both in latitude and altitude.Semi-humid EBLF is projected to shrink the most,by 57,984 km2(51.5%of its present range),while monsoon EBLF is expected to expand the most,by 44,881 km2(64.7%of its present range).The suitable habitat for cold-temperate sclerophyllous EBLF and temperate shrublands may disappear entirely in Yunnan.Given the over-estimate of the projected PNV shift without accounting for the lag effects,these findings are still useful in planning future conservation and management efforts,which should prioritize PNV types experiencing drastic changes in temperature(e.g.,mid-mountain moist EBLF),precipitation(e.g.,mountain mossy EBLF),and distribution area(e.g.,semi-humid EBLF and cold-temperate sclerophyllous EBLF).展开更多
Urban wind environments are closely related to air pollution and outdoor human comfort.The urban natural ventilation potential(NVP)is an important factor in urban planning and design.However,for ventilation studies on...Urban wind environments are closely related to air pollution and outdoor human comfort.The urban natural ventilation potential(NVP)is an important factor in urban planning and design.However,for ventilation studies on urban scales,neither macroscale numerical simulations(i.e.,WRF,MM5,etc.)nor microscale computational fluid dynamics(CFD)simulations can conduct efficient analyses.Based on the similarity between water flows and airflows,an efficient approach is proposed in this paper to map the urban NVP.Through integrating the urban terrain model,urban form model,and prevailing wind pressure model,an airflow digital elevation model(AF-DEM),which represents the resistance to airflow and can be used for a hydrological simulation,is generated and applied to evaluate the urban airflow patterns under different terrain,urban form and ambient wind conditions.The objective was to develop a simulation platform that can efficiently predict the distribution of natural ventilation corridor and NVP.The stream network calculated through the simulation is regarded as potential ventilation corridors within the city,and an index calculated from the coverage rate of wind corridors(CRW)is proposed for evaluating the relative NVP.Taking Nanjing as a case study,8 AF-DEMs based on different wind directions and wind speed conditions are generated,and their corresponding ventilation corridor maps are constructed.The results are in good agreement with the empirical evidence,indicating that the hydrological model,though a rudimentary approximation of the actual airflows,was effective in revealing the natural ventilation corridor and characterize the relative NVP.Moreover,the implementation of this novel method is simple and convenient,and it has great application potential and value in urban design and management.展开更多
Net Primary Productivity (NPP) is an important parameter, which is closely connected with global climate change, the global carbon balance and cycle. The study of climate- vegetation interaction is the basis for res...Net Primary Productivity (NPP) is an important parameter, which is closely connected with global climate change, the global carbon balance and cycle. The study of climate- vegetation interaction is the basis for research on the responses of terrestrial ecosystemto global change and mainly comprises two important components: climate vegetation classification and the NPP of the natural vegetation. Comparing NPP estimated from the classification indices-based model with NPP derived from measurements at 3767 sites in China indicated that the classification indices-based model was capable of estimating large scale NPP. Annual cumulative temperature above 0~C and a moisture index, two main factors affecting NPP, were spatially plotted with the ArcGIS grid tool based on measured data in 2348 meteorological stations from 1961 to 2006. The distribution of NPP for potential vegetation classes under present climate conditions was simulated by the classification indices-based model. The model estimated the total NPP of potential terrestrial vegetation of China to fluctuate between 1.93 and 4.54 Pg C year-1. It pro- vides a reliable means for scaling-up from site to regional scales, and the findings could potentially favor China's position in reducing global warming gases as outlined in the Kyoto Protocol in order to fulfill China's commitment of reducing greenhouse gases.展开更多
Subthreshold conduction is governed by the potential distribution. We focus on full two-dimensional(2D) analytical modeling in order to evaluate the 2D potential profile within the active area of Fin FET structure.S...Subthreshold conduction is governed by the potential distribution. We focus on full two-dimensional(2D) analytical modeling in order to evaluate the 2D potential profile within the active area of Fin FET structure.Surfaces and interfaces, which are key nanowire elements, are carefully studied. Different structures have different boundary conditions, and therefore different effects on the potential distributions. A range of models in Fin FET are reviewed in this paper. Parabolic approximation and evanescent mode are two different basic math methods to simplify the Poisson's equation. Both superposition method and parabolic approximation are widely used in heavily doped devices. It is helpful to learn performances of MOSFETs with different structures. These two methods achieved improvement to face different structures from heavily doped devices or lightly doped devices to junctionless transistors.展开更多
文摘To the Editor:Irreversible electroporation (IRE) is a CE- and FDA- approved treatment modality for pancreatic and liver tumors that is based on the site-confined destruction of tumor tissue by multiple short, high-intensity electrical pulses.
基金funded by the National Natural Science Foundation of China(grants No.30960264,31160475 and 42071258)Open Research Fund of TPESER(grant No.TPESER202208)+2 种基金Special Fund for Basic Scientific Research of Central Colleges,Chang’an University,China(grant No.300102353501)Natural Science Foundation of Gansu Province,China(grant No.22JR5RA857)Higher Education Novel Foundation of Gansu Province,China(grant No.2021B-130)。
文摘Potential natural vegetation(PNV)is a valuable reference for ecosystem renovation and has garnered increasing attention worldwide.However,there is limited knowledge on the spatio-temporal distributions,transitional processes,and underlying mechanisms of global natural vegetation,particularly in the case of ongoing climate warming.In this study,we visualize the spatio-temporal pattern and inter-transition procedure of global PNV,analyse the shifting distances and directions of global PNV under the influence of climatic disturbance,and explore the mechanisms of global PNV in response to temperature and precipitation fluctuations.To achieve this,we utilize meteorological data,mainly temperature and precipitation,from six phases:the Last Inter-Glacial(LIG),the Last Glacial Maximum(LGM),the Mid Holocene(MH),the Present Day(PD),2030(20212040)and 2090(2081–2100),and employ a widely-accepted comprehensive and sequential classification sy–stem(CSCS)for global PNV classification.We find that the spatial patterns of five PNV groups(forest,shrubland,savanna,grassland and tundra)generally align with their respective ecotopes,although their distributions have shifted due to fluctuating temperature and precipitation.Notably,we observe an unexpected transition between tundra and savanna despite their geographical distance.The shifts in distance and direction of five PNV groups are mainly driven by temperature and precipitation,although there is heterogeneity among these shifts for each group.Indeed,the heterogeneity observed among different global PNV groups suggests that they may possess varying capacities to adjust to and withstand the impacts of changing climate.The spatio-temporal distributions,mutual transitions and shift tendencies of global PNV and its underlying mechanism in face of changing climate,as revealed in this study,can significantly contribute to the development of strategies for mitigating warming and promoting re-vegetation in degraded regions worldwide.
文摘Using ground water vapor pressure and precipitation data at four times of one day during 1985- 2014 in each county( city) of Anyang,precipitable water at each station was calculated,and temporal-spatial distribution of atmospheric maximum precipitable water and its change trend over the years in the city were analyzed. Results showed that atmospheric maximum precipitable water in Anyang City had the characteristics of summer far more than winter,autumn slightly higher than spring,west and south more,and east and north less,and presented the increasing trend year by year. We further analyzed the characteristic of monthly rainfall enhancement potential in each county,and mean in whole year was 80%. In spring and winter,rainfall enhancement potential in the west was bigger than east,while rainfall enhancement potential in the east was bigger than west in summer and autumn. The research provides reference basis for rationally carrying out artificial rainfall work,which could effectively ease uneven temporal-spatial distribution problem of water resource in Anyang City.
基金Supported by the Guangdong Basic and Applied Basic Research Foundation(Nos.2022A1515011836,2021A1515110851)the Science and Technology Planning Project of Guangzhou(No.202201010230)+5 种基金the Special Support Program for Cultivating High-Level Talents in Guangdong Province(No.2019BT02H594)the Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou)(No.GML2019ZD0104)the Open Fund of Key Laboratory of Marine Geology and EnvironmentChinese Academy of Sciences(CAS)(No.MGE2020KG01)the National Natural Science Foundation of China(Nos.U1901217,91855101,41876052,42076218)Dr.Junhui YU is funded by the Special Research Assistant Funding Program of CAS。
文摘The southwestern depression of the Qiongdongnan Basin(QDNB)hosts thick Cenozoic sediments and awaits major hydrocarbon discovery.Multichannel seismic(MCS)profile CFT2011 across the southwestern QDNB reveals a~60-km-wide fuzzy reflection zone(FRZ)within the sediments,but its origin and distribution remain unclear.Here ocean bottom seismometer(OBS)data of Line CFT2011 are processed with focus on the velocity structures by traveltime tomography inversion and analyzed together with the coincident and adjacent MCS profiles.The OBS velocity results show that the giant FRZ features lower velocity with difference up to 1.5 km/s and smaller vertical velocity gradient than the surrounding sedimentary sequences at the same depth,likely resulting from enhanced fluid infilling.The MCS profile exhibits that the giant FRZ is about 3-9-km thick and extends from the Paleogene strata rich in organic matters upward to the lower Pleistocene sediments.Within the shallow overlying sediments,multiple bright spots with reverse polarity are imaged and their reflection amplitudes increase with offset,consistent with the features of gas-charged sediments.They are probably shallow gas reservoirs with gases sourced from the deep FRZ.Therefore,the FRZ is proposed to be a giant gas-charged zone,which probably contains lots of hydrocarbon gases migrated vertically from the deep Paleogene source rocks through the boundary faults of the depressions and the minor fractures generated under overpressure.This FRZ is also imaged on the adjacent MCS profiles MCS-L1 and MCS-L2 with the width of about 40 km and 68 km,respectively.It is roughly estimated to cover an area of~1900 km2 and host a volume of~11400 km3 assuming an average thickness of 6 km,implying huge natural gas potential in the sedimentary depression of the southwestern QDNB of the South China Sea.
文摘Since Serbia disposes with significant natural potentials, it could have been among the most attractive countries in Europe only if the historical circumstances had been different. Existing natural resources and possibilities for their improvement demand planned strategy to make them efficient. Tourism, as a significant instrument of development, can and should take an active part in the strategy of sustainable development. Special attention in the paper is paid to the development of Vrnjacka Banja Spa as it is one of the main tourist destinations in Serbia. The strengths, weaknesses, opportunities, and threats of a business venture (SWOT) analysis offers the basic elements for defining the strategic direction and program priorities, measures and targets for improving the overall development of spas in Serbia. To identify the SWOT factors, we used materials from a number of studies on Serbian tourism, surveys on tourists in Vrnjcka Banja Spa and analysis of the market and competition. The SWOT analysis proves that the priority in development of spas in Serbia is attractiveness of the destination which involves the spa-health tourism with great potential in complementary forms of tourism, such as sport-recreational, cultural, transit and hunting tourism. It means that the future strategy should be based on improving and involving modern spa products. It means improving and maximizing marketing so as to make the tourist destination attractive. It further implies maximum investment in modern tourist products.
基金The Major Program for Basic Research Project of Yunnan Province,No.202101B C070002The Second Comprehensive Scientific Expedition of the Qinghai-Tibet Plateau,No.2019QZKK 04020101。
文摘Potential Natural Vegetation(PNV)represents the climax of vegetation succession in a natural environment,free from significant disturbances.The reconstruction of PNV is widely used to study climate-vegetation relationships and predict future vegetation distributions.However,fine-scale PNV maps with high accuracy are still rare in biodiversity hotspots due to the complexity of ecosystems and limited field observations.In this study,we mapped the spatiotemporal distribution of 16 PNV types using adequate field and literature data,and an improved Comprehensive and Sequential Classification System(CSCS)approach under current(2005-2016)and future(2021-2080)climate scenarios in Yunnan province,Southwest China.We found that 1)from T0(2005-2016)to T3(2021-2080),regions with cold alpine PNV types,such as mid-mountain humid evergreen broad-leaved forests(EBLF),are projected to experience more significant temperature increases compared to regions with warm PNV types,like tropic rainforests and monsoon rainforests.High-emission scenarios(SSP585)are expected to result in temperature increases approximately 2°C higher than low-emission scenarios(SSP126).Precipitation is projected to increase for water-deficient PNV types(e.g.,monsoon rainforest and semi-humid EBLF)but decrease for humid PNV types(e.g.,rainforest and mountain mossy EBLF).The SSP370 scenario predicts a slightly smaller increase in precipitation compared to other scenarios.2)All PNV types are expected to shift to higher latitudes(by an average of 0.86°)and higher elevations(by an average of 454 m)by T3,based on their current niches.Alpine PNV types are more sensitive to climate change and are projected to shift more prominently than other types.For example,mountain mossy EBLF is expected to move 1.78°northward,while mid-mountain moist EBLF is projected to rise by 578 m.3)Cold PNV types are likely to be replaced by warm types both in latitude and altitude.Semi-humid EBLF is projected to shrink the most,by 57,984 km2(51.5%of its present range),while monsoon EBLF is expected to expand the most,by 44,881 km2(64.7%of its present range).The suitable habitat for cold-temperate sclerophyllous EBLF and temperate shrublands may disappear entirely in Yunnan.Given the over-estimate of the projected PNV shift without accounting for the lag effects,these findings are still useful in planning future conservation and management efforts,which should prioritize PNV types experiencing drastic changes in temperature(e.g.,mid-mountain moist EBLF),precipitation(e.g.,mountain mossy EBLF),and distribution area(e.g.,semi-humid EBLF and cold-temperate sclerophyllous EBLF).
基金This research was supported by the National Natural Science Foundation of China(No.51578277)Major Program of National Natural Science Foundation of China(No.51538005).
文摘Urban wind environments are closely related to air pollution and outdoor human comfort.The urban natural ventilation potential(NVP)is an important factor in urban planning and design.However,for ventilation studies on urban scales,neither macroscale numerical simulations(i.e.,WRF,MM5,etc.)nor microscale computational fluid dynamics(CFD)simulations can conduct efficient analyses.Based on the similarity between water flows and airflows,an efficient approach is proposed in this paper to map the urban NVP.Through integrating the urban terrain model,urban form model,and prevailing wind pressure model,an airflow digital elevation model(AF-DEM),which represents the resistance to airflow and can be used for a hydrological simulation,is generated and applied to evaluate the urban airflow patterns under different terrain,urban form and ambient wind conditions.The objective was to develop a simulation platform that can efficiently predict the distribution of natural ventilation corridor and NVP.The stream network calculated through the simulation is regarded as potential ventilation corridors within the city,and an index calculated from the coverage rate of wind corridors(CRW)is proposed for evaluating the relative NVP.Taking Nanjing as a case study,8 AF-DEMs based on different wind directions and wind speed conditions are generated,and their corresponding ventilation corridor maps are constructed.The results are in good agreement with the empirical evidence,indicating that the hydrological model,though a rudimentary approximation of the actual airflows,was effective in revealing the natural ventilation corridor and characterize the relative NVP.Moreover,the implementation of this novel method is simple and convenient,and it has great application potential and value in urban design and management.
文摘Net Primary Productivity (NPP) is an important parameter, which is closely connected with global climate change, the global carbon balance and cycle. The study of climate- vegetation interaction is the basis for research on the responses of terrestrial ecosystemto global change and mainly comprises two important components: climate vegetation classification and the NPP of the natural vegetation. Comparing NPP estimated from the classification indices-based model with NPP derived from measurements at 3767 sites in China indicated that the classification indices-based model was capable of estimating large scale NPP. Annual cumulative temperature above 0~C and a moisture index, two main factors affecting NPP, were spatially plotted with the ArcGIS grid tool based on measured data in 2348 meteorological stations from 1961 to 2006. The distribution of NPP for potential vegetation classes under present climate conditions was simulated by the classification indices-based model. The model estimated the total NPP of potential terrestrial vegetation of China to fluctuate between 1.93 and 4.54 Pg C year-1. It pro- vides a reliable means for scaling-up from site to regional scales, and the findings could potentially favor China's position in reducing global warming gases as outlined in the Kyoto Protocol in order to fulfill China's commitment of reducing greenhouse gases.
文摘Subthreshold conduction is governed by the potential distribution. We focus on full two-dimensional(2D) analytical modeling in order to evaluate the 2D potential profile within the active area of Fin FET structure.Surfaces and interfaces, which are key nanowire elements, are carefully studied. Different structures have different boundary conditions, and therefore different effects on the potential distributions. A range of models in Fin FET are reviewed in this paper. Parabolic approximation and evanescent mode are two different basic math methods to simplify the Poisson's equation. Both superposition method and parabolic approximation are widely used in heavily doped devices. It is helpful to learn performances of MOSFETs with different structures. These two methods achieved improvement to face different structures from heavily doped devices or lightly doped devices to junctionless transistors.