Afforestation is believed to be an effective practice to reduce global warming by sequestering large amounts of carbon in plant biomass and soil.However,the factors that determine the rate of carbon sequestration with...Afforestation is believed to be an effective practice to reduce global warming by sequestering large amounts of carbon in plant biomass and soil.However,the factors that determine the rate of carbon sequestration with afforestation are still poorly understood.We analyzed ecosystem carbon exchange after afforestation based on eddy covariance measurements with the aim to identify factors responsible for the rate of carbon exchange following afforestation.The results indicated that afforestation in the tropical/subtropical and temperate climate zones had greater capacities for carbon sequestration than those in boreal zones.Net ecosystem production(NEP),gross primary production(GPP)and ecosystem respiration(RE)varied greatly with age groups over time.Specifically,NEP was initially less than zero in the\10 year group and then increased to its peak in the 10-20 year group.Afforestation of varied previous land use types and planting of diverse tree species did not result in different carbon fluxes.The general linear model showed that climate zone and age of afforestation were the dominant factors influencing carbon sequestration.These factors jointly controlled 51%,61%and 63%of the variation in NEP,GPP and RE,respectively.Compared to the strong regulation of climate on GPP and RE,NEP showed greater sensitivity to the age of afforestation.These results increase our understanding of the variation in ecosystem carbon exchange of afforestation and suggest that afforestation in subtropical and temperate areas after 20 years would yield greater carbon sink benefits than would afforestation of boreal regions.展开更多
Learning programming has become an important part of education.However,most students have extreme difficulty learning programming and complex algorithms.This is because programming has a hierarchical logic.Solving com...Learning programming has become an important part of education.However,most students have extreme difficulty learning programming and complex algorithms.This is because programming has a hierarchical logic.Solving complex problems requires students to develop skills in decomposing problems.To this end,this paper describes an effective method to develop an online platform for teaching complex algorithms.展开更多
The approval of Epidiolex,an anti-epileptic drug containing cannabidiol(CBD)as its active component,has brought hope to patients with refractory epilepsy.However,the anti-seizure effect of full-spectrum hemp extract(H...The approval of Epidiolex,an anti-epileptic drug containing cannabidiol(CBD)as its active component,has brought hope to patients with refractory epilepsy.However,the anti-seizure effect of full-spectrum hemp extract(HE),a CBD-enriched hemp oil,remains unclear.In this study,we investigated the anti-seizure effect of HE using drug-induced seizure models.Our findings revealed that HE significantly reduced seizure susceptibility comparable to CBD at the same doses.Moreover,we explored the pharmacokinetic properties of CBD in HE and observed improved characteristics such as faster oral absorption,enhanced brain distribution,and slower elimination.We further assessed the anti-seizure effects of the other five main non-addictive components in HE.Among these components,cannabichromene(CBC)and cannabinol(CBN)showed significant anti-seizure effects.To gain insights into the mechanisms of CBC and CBN,we investigated their allosteric modulation on the GABA_(A) receptor.Our results revealed that CBC enhanced GABA-induced currents in both Xenopus laevis oocytes and mouse primary cortical neurons.Additionally,we identified V436 in the𝛽2 subunit of the GABA_(A) receptor as a critical binding site for CBC.These findings provide compelling evidence for the anti-seizure activities of HE and shed light on its underlying mechanisms.Our study provides insights into the broader therapeutic potential of hemp extracts and suggests their possible development as anti-seizure treatments.展开更多
TiO_(2)-based films are one of the most attractive photocatalysts owing to their highly cost-effective properties.Nevertheless,most TiO_(2)-based photocatalytic films for dye degradation are in the form of robust film...TiO_(2)-based films are one of the most attractive photocatalysts owing to their highly cost-effective properties.Nevertheless,most TiO_(2)-based photocatalytic films for dye degradation are in the form of robust films(without flexibility),TiO_(2)coatings on carbon matrix(with leakage risk),or surface-covered TiO_(2)hybrids(not favorite to contact with external molecules).Therefore,the development of durable and highly efficient TiO_(2)photocatalytic films for dye degradation is still needed.Here,we fabricated soft photocatalytic hybrid membranes(TANFs)from TiO_(2)nanotubes(Ti NT)and aramid nanofiber(ANF)by a facile vacuum filtration process.The similar morphology and dimension of Ti NT and ANF enable them intricately intertwine with each other in the membrane network.Under an appropriate mixing ratio,the TANF exhibited significantly improved optical and mechanical properties.When used for dye degradation,the membrane showed excellent photocatalytic performance and could keep stable activity and integrated state for repeated usage.展开更多
Quantifying the carbon budgets of terrestrial ecosystems is the foundation on which to understand the role of these ecosystems as carbon sinks and to mitigate global climate change. Through a re-examination of the con...Quantifying the carbon budgets of terrestrial ecosystems is the foundation on which to understand the role of these ecosystems as carbon sinks and to mitigate global climate change. Through a re-examination of the conceptual framework of ecosystem productivity and the integration of multi-source data, we assumed that the entire terrestrial ecosystems in China to be a large-scale regional biome-society system. We approximated the carbon fluxes of key natural and anthropogenic processes at a regional scale, including fluxes of emissions from reactive carbon and creature ingestion, and fluxes of emissions from anthropogenic and natural disturbances. The gross primary productivity, ecosystem respiration and net ecosystem productivity （NEP） in China were 7.78, 5.89 and 1.89 PgC a^-1, respectively, during the period from 2001 to 2010. After accounting for the consumption of reactive carbon and creature ingestion （0.078 PgC a^-1）, fires （0.002 PgC a^-1）, water erosion （0.038 PgC a^-1） and agri- cultural and forestry utilization （0.806 PgC a^-1）, the final carbon sink in China was about 0.966 PgC a^-1; this was considered as the climate-based potential terrestrial eco- system carbon sink for the current climate conditions in China. The carbon emissions caused by anthropogenic disturbances accounted for more than 42 % of the NEP, which indicated that humans can play an important role in increasing terrestrial carbon sequestration and mitigating global climate change. This role can be fulfilled by reducing the carbon emissions caused by human activities and by prolonging the residence time of fixed organic carbon in the large-scale regional biome-society system through the improvement of ecosystem management.展开更多
A stable soil pH is essential for maintaining the structure and functions of ecosystems[1].In previous decades,the development model of high energy consumption has rapidly increased the emission of acid precursors.Thi...A stable soil pH is essential for maintaining the structure and functions of ecosystems[1].In previous decades,the development model of high energy consumption has rapidly increased the emission of acid precursors.This has not only resulted in the direct input of acidity into the soil but also in the production of acidity through elements cycling,both of which produce protons(Fig.S1 online)[2].Recent studies have shown that atmospheric acid deposition has decreased by more than half compared with that during the 1990s.The decrease in acid deposition in Europe and North-America has resulted in recovery of soil acidification[3].展开更多
基金The work was supported by the National Natural Science Foundation of China(Nos.31600347 and 41501381)National Key Research and Development Program of China(No.2016YFA0600103)International Partnership Program of Chinese Academy of Sciences(No.121311KYSB20170004).
文摘Afforestation is believed to be an effective practice to reduce global warming by sequestering large amounts of carbon in plant biomass and soil.However,the factors that determine the rate of carbon sequestration with afforestation are still poorly understood.We analyzed ecosystem carbon exchange after afforestation based on eddy covariance measurements with the aim to identify factors responsible for the rate of carbon exchange following afforestation.The results indicated that afforestation in the tropical/subtropical and temperate climate zones had greater capacities for carbon sequestration than those in boreal zones.Net ecosystem production(NEP),gross primary production(GPP)and ecosystem respiration(RE)varied greatly with age groups over time.Specifically,NEP was initially less than zero in the\10 year group and then increased to its peak in the 10-20 year group.Afforestation of varied previous land use types and planting of diverse tree species did not result in different carbon fluxes.The general linear model showed that climate zone and age of afforestation were the dominant factors influencing carbon sequestration.These factors jointly controlled 51%,61%and 63%of the variation in NEP,GPP and RE,respectively.Compared to the strong regulation of climate on GPP and RE,NEP showed greater sensitivity to the age of afforestation.These results increase our understanding of the variation in ecosystem carbon exchange of afforestation and suggest that afforestation in subtropical and temperate areas after 20 years would yield greater carbon sink benefits than would afforestation of boreal regions.
基金by the XJTLU Research Fund(Grant No.RDF-21-01-053,TDF21/22-R23-160)External Research Fund(Grant No.RDS10120220093,RDS10120220021).
文摘Learning programming has become an important part of education.However,most students have extreme difficulty learning programming and complex algorithms.This is because programming has a hierarchical logic.Solving complex problems requires students to develop skills in decomposing problems.To this end,this paper describes an effective method to develop an online platform for teaching complex algorithms.
基金supported by Chinese National Programs for Brain Science and Brain-like intelligence technology(2021ZD0202102)the National Natural Science Foundation of China(31871083,81371432,82271498 and 32000674)the Ningxia Hui Autonomous Region Key Research and Development Project(2022BEG02042).
文摘The approval of Epidiolex,an anti-epileptic drug containing cannabidiol(CBD)as its active component,has brought hope to patients with refractory epilepsy.However,the anti-seizure effect of full-spectrum hemp extract(HE),a CBD-enriched hemp oil,remains unclear.In this study,we investigated the anti-seizure effect of HE using drug-induced seizure models.Our findings revealed that HE significantly reduced seizure susceptibility comparable to CBD at the same doses.Moreover,we explored the pharmacokinetic properties of CBD in HE and observed improved characteristics such as faster oral absorption,enhanced brain distribution,and slower elimination.We further assessed the anti-seizure effects of the other five main non-addictive components in HE.Among these components,cannabichromene(CBC)and cannabinol(CBN)showed significant anti-seizure effects.To gain insights into the mechanisms of CBC and CBN,we investigated their allosteric modulation on the GABA_(A) receptor.Our results revealed that CBC enhanced GABA-induced currents in both Xenopus laevis oocytes and mouse primary cortical neurons.Additionally,we identified V436 in the𝛽2 subunit of the GABA_(A) receptor as a critical binding site for CBC.These findings provide compelling evidence for the anti-seizure activities of HE and shed light on its underlying mechanisms.Our study provides insights into the broader therapeutic potential of hemp extracts and suggests their possible development as anti-seizure treatments.
基金the financial supports from the Instrument&Equipment Open Funding of Nanjing University of Science and TechnologyNational Natural Science Foundation of China(Nos.21875108 and 22105103)+3 种基金the Natural Science Foundation of Jiangsu Province(No.BK20200471)the Fundamental Research Funds for the Central Universities(No.30921013106)the technical cooperation project with Nantong Junjiang Material Science and Technology Co.,Ltd.(No.2022320104001955)the Key R&D Project of Shanxi Province(No.2022JBGS3–12)。
文摘TiO_(2)-based films are one of the most attractive photocatalysts owing to their highly cost-effective properties.Nevertheless,most TiO_(2)-based photocatalytic films for dye degradation are in the form of robust films(without flexibility),TiO_(2)coatings on carbon matrix(with leakage risk),or surface-covered TiO_(2)hybrids(not favorite to contact with external molecules).Therefore,the development of durable and highly efficient TiO_(2)photocatalytic films for dye degradation is still needed.Here,we fabricated soft photocatalytic hybrid membranes(TANFs)from TiO_(2)nanotubes(Ti NT)and aramid nanofiber(ANF)by a facile vacuum filtration process.The similar morphology and dimension of Ti NT and ANF enable them intricately intertwine with each other in the membrane network.Under an appropriate mixing ratio,the TANF exhibited significantly improved optical and mechanical properties.When used for dye degradation,the membrane showed excellent photocatalytic performance and could keep stable activity and integrated state for repeated usage.
基金supported by the National Basic Research Program of China(2010CB833504)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA05050601,XDA05050702)
文摘Quantifying the carbon budgets of terrestrial ecosystems is the foundation on which to understand the role of these ecosystems as carbon sinks and to mitigate global climate change. Through a re-examination of the conceptual framework of ecosystem productivity and the integration of multi-source data, we assumed that the entire terrestrial ecosystems in China to be a large-scale regional biome-society system. We approximated the carbon fluxes of key natural and anthropogenic processes at a regional scale, including fluxes of emissions from reactive carbon and creature ingestion, and fluxes of emissions from anthropogenic and natural disturbances. The gross primary productivity, ecosystem respiration and net ecosystem productivity （NEP） in China were 7.78, 5.89 and 1.89 PgC a^-1, respectively, during the period from 2001 to 2010. After accounting for the consumption of reactive carbon and creature ingestion （0.078 PgC a^-1）, fires （0.002 PgC a^-1）, water erosion （0.038 PgC a^-1） and agri- cultural and forestry utilization （0.806 PgC a^-1）, the final carbon sink in China was about 0.966 PgC a^-1; this was considered as the climate-based potential terrestrial eco- system carbon sink for the current climate conditions in China. The carbon emissions caused by anthropogenic disturbances accounted for more than 42 % of the NEP, which indicated that humans can play an important role in increasing terrestrial carbon sequestration and mitigating global climate change. This role can be fulfilled by reducing the carbon emissions caused by human activities and by prolonging the residence time of fixed organic carbon in the large-scale regional biome-society system through the improvement of ecosystem management.
基金supported by the National Natural Science Foundation of China(31872690 and 31988102)the National Key Research&Development Program of China(2017YFA0604803)the Youth Innovation Research Project from Key Laboratory of Ecosystem Network Observation and Modeling,Chinese Academy of Sciences。
文摘A stable soil pH is essential for maintaining the structure and functions of ecosystems[1].In previous decades,the development model of high energy consumption has rapidly increased the emission of acid precursors.This has not only resulted in the direct input of acidity into the soil but also in the production of acidity through elements cycling,both of which produce protons(Fig.S1 online)[2].Recent studies have shown that atmospheric acid deposition has decreased by more than half compared with that during the 1990s.The decrease in acid deposition in Europe and North-America has resulted in recovery of soil acidification[3].
