Water storage has important significance for understanding water cycles of global and local domains and for monitoring climate and environmental changes. As a key variable in hydrology, water storage change represents...Water storage has important significance for understanding water cycles of global and local domains and for monitoring climate and environmental changes. As a key variable in hydrology, water storage change represents the sum of precipitation, evaporation, surface runoff, soil water and groundwater exchanges. Water storage change data during the period of 2003-2008 for the source region of the Yellow River were collected from Gravity Recovery and Climate Experiment (GRACE) satellite data. The monthly actual evaporation was estimated according to the water balance equation. The simulated actual evaporation was significantly consistent and correlative with not only the observed pan (20 cm) data, but also the simulated results of the version 2 of Simple Biosphere model. The average annual evaporation of the Tangnaihai Basin was 506.4 mm, where evaporation in spring, summer, autumn and winter was 130.9 mm, 275.2 mm, 74.3 mm and 26.1 mm, and accounted for 25.8%, 54.3%, 14.7% and 5.2% of the average annual evaporation, respectively, The precipitation increased slightly and the actual evaporation showed an obvious decrease. The water storage change of the source region of the Yellow River displayed an increase of 0.51 mm per month from 2003 to 2008, which indicated that the storage capacity has significantly increased, probably caused by the degradation of permafrost and the increase of the thickness of active layers. The decline of actual evaporation and the increase of water storage capacity resulted in the increase of river runoff.展开更多
Siberian Pine (Pinus sibirica) is an ecologically and eco-nomically important species in pristine forests throughout northern Rus-sia. Four provenances of P. sibirica were introduced from Mongolia and Russia to the ...Siberian Pine (Pinus sibirica) is an ecologically and eco-nomically important species in pristine forests throughout northern Rus-sia. Four provenances of P. sibirica were introduced from Mongolia and Russia to the Greater Xing’an Range (the Daxing’anling), northeast China in 1993. The aim of this research was to study genetic variation and selection of the introduced four Pinus sibirica provenances. Heights (H), basal diameters (BD), survival rates (SR) and crown lengths (CL) of different families were measured as primary outcomes in different growth years. Results of data analyses demonstrated high coefficients of phenotypic variation (PCV) and heritability (H2) for H, BD and CL at 18 years after introduction. PCV and H2 increased with age. Correlations of growth traits between any two growth years were all significantly positive, but the correlation coefficient was smaller when the growth year interval was larger. Correlations between H and the original environment factors decreased gradually, indicating that with long-term subsistence in the new environment, the influence of the source environment declined. Colligation of multiple traits to estimate provenances showed that Novosibirsk, Tomsk, and Altai Mountains had higher survival rates and biomass, and proved more suitable for introduction and plantation in the Greater Xing’an Range in China.展开更多
Air pollution has seriously endangered human health and the natural ecosystem during the last decades.Air quality monitoring stations(AQMS)have played a critical role in providing valuable data sets for recording regi...Air pollution has seriously endangered human health and the natural ecosystem during the last decades.Air quality monitoring stations(AQMS)have played a critical role in providing valuable data sets for recording regional air pollutants.The spatial representativeness of AQMS is a critical parameter when choosing the location of stations and assessing effects on the population to long-term exposure to air pollution.In this paper,we proposed a methodological framework for assessing the spatial representativeness of the regional air quality monitoring network and applied it to ground-based PM_(2.5)observation in the mainland of China.Weighted multidimensional Euclidean distance between each pixel and the stations was used to determine the representativeness of the existing monitoring network.In addition,the K-means clustering method was adopted to improve the spatial representativeness of the existing AQMS.The results showed that there were obvious differences among the representative area of 1820 stations in the mainland of China.The monitoring stations could well represent the PM_(2.5)spatial distribution of the entire region,and the effectively represented area(i.e.the area where the Euclidean distance between the pixels and the stations was lower than the average value)accounted for 67.32%of the total area and covered 93.12%of the population.Forty additional stations were identified in the Northwest,North China,and Northeast regions,which could improve the spatial representativeness by 14.31%.展开更多
This paper summarizes the factors affecting schistosomiasis transmission in the middle and lower reaches of the Yangtze River before and after the completion of the Three Gorges Dam and analyzes schistosomiasis preval...This paper summarizes the factors affecting schistosomiasis transmission in the middle and lower reaches of the Yangtze River before and after the completion of the Three Gorges Dam and analyzes schistosomiasis prevalence trends to provide a basis for the application of the Three Gorges project methodologies in other areas.The Three Gorges Dam has demonstrated a positive effect on schistosomiasis control.Hubei,Hunan,Jiangxi,Anhui,and Jiangsu in the middle and lower reaches of the Yangtze River are currently regions with a high prevalence of schistosomiasis.These five provinces contained 97.62% of known snail areas and 93.66% of calculated schistosomiasis cases with 90.07% of counties (cities,districts) not yet meeting the criteria for schistosomiasis transmission interruption by the end of 2016.After the Three Gorges Dam was built,the prevalence of schistosomiasis in the middle and lower reaches of the Yangtze River decreased.By the end of 2016,the estimated number of cases decreased by 92.75% and the snail habitat areas decreased by 6.56% compared to 2004.No acute schistosomiasis cases have occurred for two consecutive years since 2015.展开更多
Selector devices are indispensable components of large-scale memristor array systems.The thereinto,ovonic threshold switching(OTS)selector is one of the most suitable candidates for selector devices,owing to its high ...Selector devices are indispensable components of large-scale memristor array systems.The thereinto,ovonic threshold switching(OTS)selector is one of the most suitable candidates for selector devices,owing to its high selectivity and scalability.However,OTS selectors suffer from poor endurance and stability which are persistent tricky problems for applica-tion.Here,we report on a multilayer OTS selector based on simple GeSe and doped-GeSe.The experimental results show im-proving selector performed extraordinary endurance up to 1010 and the fluctuation of threshold voltage is 2.5%.The reason for the improvement may lie in more interface states which strengthen the interaction among individual layers.These develop-ments pave the way towards tuning a new class of OTS materials engineering,ensuring improvement of electrical perform-ance.展开更多
We aimed to explore the molecular mechanism that were involved in SPINK1-induced proliferation and clonogenic survival of human colorectal carcinoma(CRC)HT29 cells.Initially,we generated HT29 cells either permanently ...We aimed to explore the molecular mechanism that were involved in SPINK1-induced proliferation and clonogenic survival of human colorectal carcinoma(CRC)HT29 cells.Initially,we generated HT29 cells either permanently silencing or overexpressing SPINK1 protein.The results showed that SPINK1 overexpression(OE)significantly stimulated the proliferation and clonal formation of HT29 cells at the varied time points.Secondly,we found SPINK1 OE enhanced the ratio of LC3II/LC3I and the level of autophagy-related gene 5(ATG5),whereas SPINK1 knockdown(Kd)reversed the above outcome under normal culturing and/or fasting condition in the cells,indicating its role in autophagy enhancement.Moreover,LC3-GFP-transfected SPINK1-OE HT29 cells strengthened thefluorescence intensity compared with the untransfected control.Chloroquine(CQ)significantly decreased the level of autophagy in both control and SPINK1-OE HT29 cells.The autophagy inhibitors,CQ and 3-Methyladenine(3-MA),remarkably inhibited the proliferation and colony formation of SPINK1-OE HT29 cells,while ATG5 upregulation resulted in the growth of the cells,suggesting the important function of autophagy in cell’s growth.Thirdly,SPINK1-induced autophagy was independently of mTOR signaling as p-RPS6 and p-4EBP1 were activated in SPINK1-OE HT29 cells.Instead,Beclin1 up and down regulation were clearly observed in SPINK1-OE and SPINK1 Kd HT29 cells,respectively.Moreover,Beclin1 silencing apparently reduced autophagy in SPINK1-OE HT29 cells,indicating that SPINK1-induced autophagy was closely associated with Beclin1.Collectively,SPINK1-promoted proliferation and clonal formation of HT29 cells were closely associated with Beclin1 associated enhanced autophagy.The abovefindings would open a new window for probing the role of SPINK1-related autophagic signaling in the pathogenesis of CRC.展开更多
The problem of high similarity in homework has troubled teachers with time. Previous plagiarism detection systems are mainly realized by string matching which has a limitation, i.e., image homework cannot be detected....The problem of high similarity in homework has troubled teachers with time. Previous plagiarism detection systems are mainly realized by string matching which has a limitation, i.e., image homework cannot be detected. To this issue, we propose a new method of plagiarism detection in homework. First,we get fingerprint features of image homework by converting text homework into images. Then, we use image hashing algorithm and hamming distance to calculate the similarity of these features. Finally, we perform the empirical study on course of Computer Network Experiment, the test shows that our method not only reliably keeps the detection speedily, but also consistently ensures precision and false positive rate.展开更多
Cardiac-resident macrophages(CRMs)play important roles in homeostasis,cardiac function,and remodeling.Although CRMs play critical roles in cardiac regeneration of neonatal mice,their roles are yet to be fully elucidat...Cardiac-resident macrophages(CRMs)play important roles in homeostasis,cardiac function,and remodeling.Although CRMs play critical roles in cardiac regeneration of neonatal mice,their roles are yet to be fully elucidated.Therefore,this study aimed to investigate the dynamic changes of CRMs during cardiac ontogeny and analyze the phenotypic and functional properties of CRMs in the promotion of cardiac regeneration.During mouse cardiac ontogeny,four CRM subsets exist successively:CX3CR1+CCR2-Ly6C-MHCII-(MP1),CX3CR1lowCCR2lowLy6C-MHCII-(MP2),CX3CR1-CCR2+Ly6C+MHCII-(MP3),and CX3CR1+CCR2-Ly6C-MHCII+(MP4).MP1 cluster has different derivations(yolk sac,fetal liver,and bone marrow)and multiple functions population.Embryonic and neonatal-derived-MP1 directly promoted cardiomyocyte proliferation through Jagged-1-Notch1 axis and significantly ameliorated cardiac injury following myocardial infarction.MP2/3 subsets could survive throughout adulthood.MP4,the main population in adult mouse hearts,contributed to inflammation.During ontogeny,MP1 can convert into MP4 triggered by changes in the cellular redox state.These findings delineate the evolutionary dynamics of CRMs under physiological conditions and found direct evidence that embryonic and neonatal-derived CRMs regulate cardiomyocyte proliferation.Our findings also shed light on cardiac repair following injury.展开更多
Background:Schistosomiasis is a water-borne disease caused by trematode worms belonging to genus Schistosoma,which is prevalent most of the developing world.Transmission of the disease is usually associated with multi...Background:Schistosomiasis is a water-borne disease caused by trematode worms belonging to genus Schistosoma,which is prevalent most of the developing world.Transmission of the disease is usually associated with multiple biological characteristics and social factors but also factors can play a role.Few studies have assessed the exact and interactive influence of each factor promoting schistosomiasis transmission.Methods:We used a series of different detectors(i.e.,specific detector,risk detector,ecological detector and interaction detector)to evaluate separate and interactive effects of the environmental factors on schistosomiasis prevalence.Specifically,(i)specific detector quantifies the impact of a risk factor on an observed spatial disease pattern,which were ranked statistically by a value of Power of Determinate(PD)calculation;(ii)risk detector detects high risk areas of a disease on the condition that the study area is stratified by a potential risk factor;(iii)ecological detector explores whether a risk factor is more significant than another in controlling the spatial pattern of a disease;(iv)interaction detector probes whether two risk factors when taken together weaken or enhance one another,or whether they are independent in developing a disease.Infection data of schistosomiasis based on conventional surveys were obtained at the county level from the health authorities in Anhui Province,China and used in combination with information from Chinese weather stations and internationally available environmental data.Results:The specific detector identified various factors of potential importance as follows:Proximity to Yangtze River(0.322)>Land cover(0.285)>sunshine hours(0.256)>population density(0.109)>altitude(0.090)>the normalized different vegetation index(NDVI)(0.077)>land surface temperature at daytime(LST_(day))(0.007).The risk detector indicated that areas of schistosomiasis high risk were located within a buffer distance of 50 km from Yangtze River.The ecological detector disclosed that the factors investigated have significantly different effects.The interaction detector revealed that interaction between the factors enhanced their main effects in most cases.Conclusion:Proximity to Yangtze River had the strongest effect on schistosomiasis prevalence followed by land cover and sunshine hours,while the remaining factors had only weak influence.Interaction between factors played an even more important role in influencing schistosomiasis prevalence than each factor on its own.High risk regions influenced by strong interactions need to be targeted for disease control intervention.展开更多
Despite the increasing investment in integrated GPU and next-generation interconnect research,discrete GPU connected by PCIe still account for the dominant position of the market,the management of data communication b...Despite the increasing investment in integrated GPU and next-generation interconnect research,discrete GPU connected by PCIe still account for the dominant position of the market,the management of data communication between CPU and GPU continues to evolve.Initially,the programmer explicitly controls the data transfer between CPU and GPU.To simplify programming and enable systemwide atomic memory operations,GPU vendors have developed a programming model that provides a single,virtual address space for accessing all CPU and GPU memories in the system.The page migration engine in this model automatically migrates pages between CPU and GPU on demand.To meet the needs of high-performance workloads,the page size tends to be larger.Limited by low bandwidth and high latency interconnects compared to GDDR,larger page migration has longer delay,which may reduce the overlap of computation and transmission,waste time to migrate unrequested data,block subsequent requests,and cause serious performance decline.In this paper,we propose partial page migration that only migrates the requested part of a page to reduce the migration unit,shorten the migration latency,and avoid the performance degradation of the full page migration when the page becomes larger.We show that partial page migration is possible to largely hide the performance overheads of full page migration.Compared with programmer controlled data transmission,when the page size is 2MB and the PCIe bandwidth is 16GB/sec,full page migration is 72.72×slower,while our partial page migration achieves 1.29×speedup.When the PCIe bandwidth is changed to 96GB/sec,full page migration is 18.85×slower,while our partial page migration provides 1.37×speedup.Additionally,we examine the performance impact that PCIe bandwidth and migration unit size have on execution time,enabling designers to make informed decisions.展开更多
The authors consider non-autonomous N-body-type problems with strong force type potentials at the origin and sub-quadratic growth at infinity.Using Ljusternik-Schnirelmann theory,the authors prove the existence of unb...The authors consider non-autonomous N-body-type problems with strong force type potentials at the origin and sub-quadratic growth at infinity.Using Ljusternik-Schnirelmann theory,the authors prove the existence of unbounded sequences of critical values for the Lagrangian action corresponding to non-collision periodic solutions.展开更多
基金funded by the Global Change Research Program of China (2010CB951401)the National Natural Science Foundation of China (41030638, 41121001, 41030527,41130641,and 41201025)the One Hundred Talents Program of the Chinese Academy of Sciences
文摘Water storage has important significance for understanding water cycles of global and local domains and for monitoring climate and environmental changes. As a key variable in hydrology, water storage change represents the sum of precipitation, evaporation, surface runoff, soil water and groundwater exchanges. Water storage change data during the period of 2003-2008 for the source region of the Yellow River were collected from Gravity Recovery and Climate Experiment (GRACE) satellite data. The monthly actual evaporation was estimated according to the water balance equation. The simulated actual evaporation was significantly consistent and correlative with not only the observed pan (20 cm) data, but also the simulated results of the version 2 of Simple Biosphere model. The average annual evaporation of the Tangnaihai Basin was 506.4 mm, where evaporation in spring, summer, autumn and winter was 130.9 mm, 275.2 mm, 74.3 mm and 26.1 mm, and accounted for 25.8%, 54.3%, 14.7% and 5.2% of the average annual evaporation, respectively, The precipitation increased slightly and the actual evaporation showed an obvious decrease. The water storage change of the source region of the Yellow River displayed an increase of 0.51 mm per month from 2003 to 2008, which indicated that the storage capacity has significantly increased, probably caused by the degradation of permafrost and the increase of the thickness of active layers. The decline of actual evaporation and the increase of water storage capacity resulted in the increase of river runoff.
基金supported by grants Seedling Technology Rules of Siberia pine(No.2012-LY-183)
文摘Siberian Pine (Pinus sibirica) is an ecologically and eco-nomically important species in pristine forests throughout northern Rus-sia. Four provenances of P. sibirica were introduced from Mongolia and Russia to the Greater Xing’an Range (the Daxing’anling), northeast China in 1993. The aim of this research was to study genetic variation and selection of the introduced four Pinus sibirica provenances. Heights (H), basal diameters (BD), survival rates (SR) and crown lengths (CL) of different families were measured as primary outcomes in different growth years. Results of data analyses demonstrated high coefficients of phenotypic variation (PCV) and heritability (H2) for H, BD and CL at 18 years after introduction. PCV and H2 increased with age. Correlations of growth traits between any two growth years were all significantly positive, but the correlation coefficient was smaller when the growth year interval was larger. Correlations between H and the original environment factors decreased gradually, indicating that with long-term subsistence in the new environment, the influence of the source environment declined. Colligation of multiple traits to estimate provenances showed that Novosibirsk, Tomsk, and Altai Mountains had higher survival rates and biomass, and proved more suitable for introduction and plantation in the Greater Xing’an Range in China.
基金funded by the National Natural Science Foundation of China (41977399)the National Key Research and Development Program (2017YFC0505800)
文摘Air pollution has seriously endangered human health and the natural ecosystem during the last decades.Air quality monitoring stations(AQMS)have played a critical role in providing valuable data sets for recording regional air pollutants.The spatial representativeness of AQMS is a critical parameter when choosing the location of stations and assessing effects on the population to long-term exposure to air pollution.In this paper,we proposed a methodological framework for assessing the spatial representativeness of the regional air quality monitoring network and applied it to ground-based PM_(2.5)observation in the mainland of China.Weighted multidimensional Euclidean distance between each pixel and the stations was used to determine the representativeness of the existing monitoring network.In addition,the K-means clustering method was adopted to improve the spatial representativeness of the existing AQMS.The results showed that there were obvious differences among the representative area of 1820 stations in the mainland of China.The monitoring stations could well represent the PM_(2.5)spatial distribution of the entire region,and the effectively represented area(i.e.the area where the Euclidean distance between the pixels and the stations was lower than the average value)accounted for 67.32%of the total area and covered 93.12%of the population.Forty additional stations were identified in the Northwest,North China,and Northeast regions,which could improve the spatial representativeness by 14.31%.
文摘This paper summarizes the factors affecting schistosomiasis transmission in the middle and lower reaches of the Yangtze River before and after the completion of the Three Gorges Dam and analyzes schistosomiasis prevalence trends to provide a basis for the application of the Three Gorges project methodologies in other areas.The Three Gorges Dam has demonstrated a positive effect on schistosomiasis control.Hubei,Hunan,Jiangxi,Anhui,and Jiangsu in the middle and lower reaches of the Yangtze River are currently regions with a high prevalence of schistosomiasis.These five provinces contained 97.62% of known snail areas and 93.66% of calculated schistosomiasis cases with 90.07% of counties (cities,districts) not yet meeting the criteria for schistosomiasis transmission interruption by the end of 2016.After the Three Gorges Dam was built,the prevalence of schistosomiasis in the middle and lower reaches of the Yangtze River decreased.By the end of 2016,the estimated number of cases decreased by 92.75% and the snail habitat areas decreased by 6.56% compared to 2004.No acute schistosomiasis cases have occurred for two consecutive years since 2015.
基金supported by National Natural Science Foundation of China(Grant Nos.61974164,62074166,61804181,62004219,and 6200422).
文摘Selector devices are indispensable components of large-scale memristor array systems.The thereinto,ovonic threshold switching(OTS)selector is one of the most suitable candidates for selector devices,owing to its high selectivity and scalability.However,OTS selectors suffer from poor endurance and stability which are persistent tricky problems for applica-tion.Here,we report on a multilayer OTS selector based on simple GeSe and doped-GeSe.The experimental results show im-proving selector performed extraordinary endurance up to 1010 and the fluctuation of threshold voltage is 2.5%.The reason for the improvement may lie in more interface states which strengthen the interaction among individual layers.These develop-ments pave the way towards tuning a new class of OTS materials engineering,ensuring improvement of electrical perform-ance.
基金financially supported in part by Dalian Medical University that has no roles in study design,in the collection,analysis and interpretation of data,and etc.
文摘We aimed to explore the molecular mechanism that were involved in SPINK1-induced proliferation and clonogenic survival of human colorectal carcinoma(CRC)HT29 cells.Initially,we generated HT29 cells either permanently silencing or overexpressing SPINK1 protein.The results showed that SPINK1 overexpression(OE)significantly stimulated the proliferation and clonal formation of HT29 cells at the varied time points.Secondly,we found SPINK1 OE enhanced the ratio of LC3II/LC3I and the level of autophagy-related gene 5(ATG5),whereas SPINK1 knockdown(Kd)reversed the above outcome under normal culturing and/or fasting condition in the cells,indicating its role in autophagy enhancement.Moreover,LC3-GFP-transfected SPINK1-OE HT29 cells strengthened thefluorescence intensity compared with the untransfected control.Chloroquine(CQ)significantly decreased the level of autophagy in both control and SPINK1-OE HT29 cells.The autophagy inhibitors,CQ and 3-Methyladenine(3-MA),remarkably inhibited the proliferation and colony formation of SPINK1-OE HT29 cells,while ATG5 upregulation resulted in the growth of the cells,suggesting the important function of autophagy in cell’s growth.Thirdly,SPINK1-induced autophagy was independently of mTOR signaling as p-RPS6 and p-4EBP1 were activated in SPINK1-OE HT29 cells.Instead,Beclin1 up and down regulation were clearly observed in SPINK1-OE and SPINK1 Kd HT29 cells,respectively.Moreover,Beclin1 silencing apparently reduced autophagy in SPINK1-OE HT29 cells,indicating that SPINK1-induced autophagy was closely associated with Beclin1.Collectively,SPINK1-promoted proliferation and clonal formation of HT29 cells were closely associated with Beclin1 associated enhanced autophagy.The abovefindings would open a new window for probing the role of SPINK1-related autophagic signaling in the pathogenesis of CRC.
文摘The problem of high similarity in homework has troubled teachers with time. Previous plagiarism detection systems are mainly realized by string matching which has a limitation, i.e., image homework cannot be detected. To this issue, we propose a new method of plagiarism detection in homework. First,we get fingerprint features of image homework by converting text homework into images. Then, we use image hashing algorithm and hamming distance to calculate the similarity of these features. Finally, we perform the empirical study on course of Computer Network Experiment, the test shows that our method not only reliably keeps the detection speedily, but also consistently ensures precision and false positive rate.
基金supported by National Natural Science Foundation of China(Grant No.81871244)Primary Research&Development Plan of Jiangsu Province(BE2019700,China)+4 种基金Jiangsu Province“333”project(BRA2018016,China)six talent peaks project in Jiangsu Province(2019-WSN-122,China)Projects of International Cooperation from Jiangsu(BX2019100,China)international cooperation and exchange from Zhenjiang(GJ2020010,China)key funds from health commission of jiangsu(ZD2021009,China)。
文摘Cardiac-resident macrophages(CRMs)play important roles in homeostasis,cardiac function,and remodeling.Although CRMs play critical roles in cardiac regeneration of neonatal mice,their roles are yet to be fully elucidated.Therefore,this study aimed to investigate the dynamic changes of CRMs during cardiac ontogeny and analyze the phenotypic and functional properties of CRMs in the promotion of cardiac regeneration.During mouse cardiac ontogeny,four CRM subsets exist successively:CX3CR1+CCR2-Ly6C-MHCII-(MP1),CX3CR1lowCCR2lowLy6C-MHCII-(MP2),CX3CR1-CCR2+Ly6C+MHCII-(MP3),and CX3CR1+CCR2-Ly6C-MHCII+(MP4).MP1 cluster has different derivations(yolk sac,fetal liver,and bone marrow)and multiple functions population.Embryonic and neonatal-derived-MP1 directly promoted cardiomyocyte proliferation through Jagged-1-Notch1 axis and significantly ameliorated cardiac injury following myocardial infarction.MP2/3 subsets could survive throughout adulthood.MP4,the main population in adult mouse hearts,contributed to inflammation.During ontogeny,MP1 can convert into MP4 triggered by changes in the cellular redox state.These findings delineate the evolutionary dynamics of CRMs under physiological conditions and found direct evidence that embryonic and neonatal-derived CRMs regulate cardiomyocyte proliferation.Our findings also shed light on cardiac repair following injury.
基金This research was supported by the National Natural Science Foundation of China(81673239)the National Science Fund for Distinguished Young Scholars(No.81325017)+1 种基金Chang Jiang Scholars Program(No.T2014089)the Fourth Round of Three-Year Public Health Action Plan of Shanghai,China(15GWZK0202,15GWZK0101).
文摘Background:Schistosomiasis is a water-borne disease caused by trematode worms belonging to genus Schistosoma,which is prevalent most of the developing world.Transmission of the disease is usually associated with multiple biological characteristics and social factors but also factors can play a role.Few studies have assessed the exact and interactive influence of each factor promoting schistosomiasis transmission.Methods:We used a series of different detectors(i.e.,specific detector,risk detector,ecological detector and interaction detector)to evaluate separate and interactive effects of the environmental factors on schistosomiasis prevalence.Specifically,(i)specific detector quantifies the impact of a risk factor on an observed spatial disease pattern,which were ranked statistically by a value of Power of Determinate(PD)calculation;(ii)risk detector detects high risk areas of a disease on the condition that the study area is stratified by a potential risk factor;(iii)ecological detector explores whether a risk factor is more significant than another in controlling the spatial pattern of a disease;(iv)interaction detector probes whether two risk factors when taken together weaken or enhance one another,or whether they are independent in developing a disease.Infection data of schistosomiasis based on conventional surveys were obtained at the county level from the health authorities in Anhui Province,China and used in combination with information from Chinese weather stations and internationally available environmental data.Results:The specific detector identified various factors of potential importance as follows:Proximity to Yangtze River(0.322)>Land cover(0.285)>sunshine hours(0.256)>population density(0.109)>altitude(0.090)>the normalized different vegetation index(NDVI)(0.077)>land surface temperature at daytime(LST_(day))(0.007).The risk detector indicated that areas of schistosomiasis high risk were located within a buffer distance of 50 km from Yangtze River.The ecological detector disclosed that the factors investigated have significantly different effects.The interaction detector revealed that interaction between the factors enhanced their main effects in most cases.Conclusion:Proximity to Yangtze River had the strongest effect on schistosomiasis prevalence followed by land cover and sunshine hours,while the remaining factors had only weak influence.Interaction between factors played an even more important role in influencing schistosomiasis prevalence than each factor on its own.High risk regions influenced by strong interactions need to be targeted for disease control intervention.
文摘Despite the increasing investment in integrated GPU and next-generation interconnect research,discrete GPU connected by PCIe still account for the dominant position of the market,the management of data communication between CPU and GPU continues to evolve.Initially,the programmer explicitly controls the data transfer between CPU and GPU.To simplify programming and enable systemwide atomic memory operations,GPU vendors have developed a programming model that provides a single,virtual address space for accessing all CPU and GPU memories in the system.The page migration engine in this model automatically migrates pages between CPU and GPU on demand.To meet the needs of high-performance workloads,the page size tends to be larger.Limited by low bandwidth and high latency interconnects compared to GDDR,larger page migration has longer delay,which may reduce the overlap of computation and transmission,waste time to migrate unrequested data,block subsequent requests,and cause serious performance decline.In this paper,we propose partial page migration that only migrates the requested part of a page to reduce the migration unit,shorten the migration latency,and avoid the performance degradation of the full page migration when the page becomes larger.We show that partial page migration is possible to largely hide the performance overheads of full page migration.Compared with programmer controlled data transmission,when the page size is 2MB and the PCIe bandwidth is 16GB/sec,full page migration is 72.72×slower,while our partial page migration achieves 1.29×speedup.When the PCIe bandwidth is changed to 96GB/sec,full page migration is 18.85×slower,while our partial page migration provides 1.37×speedup.Additionally,we examine the performance impact that PCIe bandwidth and migration unit size have on execution time,enabling designers to make informed decisions.
基金supported by the National Natural Science Foundation of China(Nos.11701463,11671278).
文摘The authors consider non-autonomous N-body-type problems with strong force type potentials at the origin and sub-quadratic growth at infinity.Using Ljusternik-Schnirelmann theory,the authors prove the existence of unbounded sequences of critical values for the Lagrangian action corresponding to non-collision periodic solutions.