This paper provides guidance for the quantification and reporting of blue carbon removals in the temperate coastal ecosystems,“Italian valli da pesca”or H.C.W.(Human Controlled Wetland,Lat.45°Lon.12°),wher...This paper provides guidance for the quantification and reporting of blue carbon removals in the temperate coastal ecosystems,“Italian valli da pesca”or H.C.W.(Human Controlled Wetland,Lat.45°Lon.12°),where some pools as seagrasses,and salt marshes,are highly efficient at capturing and storing carbon dioxide(CO_(2))from the atmosphere.Halophyte salt marsh plants were found to have a%C on Dry Weight(D.W.)of 32.26±3.91(mean±standard deviation),macrophytes 33.65±7.99,seagrasses 29.23±2.23,tamarisk 48.42±2.80,while the first 5 centimetres of wetland mud,on average,had a%C of 8.56±0.94.Like the ISO(International Organization for Standardization)14064 guideline to quantify the GHG(Greenhouse Gas)emission,we have studied the different conversion factors to be used as a practical tool for measurement the CO_(2)sink activity.These factors are essential to calculate the overall carbon reduction in a project located in temperate wetland using a method as the ISO 14064.2,UNI-BNeutral,VCS VERRA or other that will come.展开更多
Objective:Glioblastoma(GBM)is the most prevalent and aggressive adult primary cancer in the central nervous system.Therapeutic approaches for GBM treatment are under intense investigation,including the use of emerging...Objective:Glioblastoma(GBM)is the most prevalent and aggressive adult primary cancer in the central nervous system.Therapeutic approaches for GBM treatment are under intense investigation,including the use of emerging immunotherapies.Here,we propose an alternative approach to treat GBM through reprogramming proliferative GBM cells into non-proliferative neurons.Methods:Retroviruses were used to target highly proliferative human GBM cells through overexpression of neural transcription factors.Immunostaining,electrophysiological recording,and bulk RNA-seq were performed to investigate the mechanisms underlying the neuronal conversion of human GBM cells.An in vivo intracranial xenograft mouse model was used to examine the neuronal conversion of human GBM cells.Results:We report efficient neuronal conversion from human GBM cells by overexpressing single neural transcription factor Neurogenic differentiation 1(Neuro D1),Neurogenin-2(Neurog2),or Achaete-scute homolog 1(Ascl1).Subtype characterization showed that the majority of Neurog2-and Neuro D1-converted neurons were glutamatergic,while Ascl1 favored GABAergic neuron generation.The GBM cell-converted neurons not only showed pan-neuronal markers but also exhibited neuron-specific electrophysiological activities.Transcriptome analyses revealed that neuronal genes were activated in glioma cells after overexpression of neural transcription factors,and different signaling pathways were activated by different neural transcription factors.Importantly,the neuronal conversion of GBM cells was accompanied by significant inhibition of GBM cell proliferation in both in vitro and in vivo models.Conclusions:These results suggest that GBM cells can be reprogrammed into different subtypes of neurons,leading to a potential alternative approach to treat brain tumors using in vivo cell conversion technology.展开更多
In the fine-grain TL dating the full o dose must be converted into the equivalent P dose. The conversion is finished by Keff-value, which is an effective or effectiveness. But the Keff can not be measured directly for...In the fine-grain TL dating the full o dose must be converted into the equivalent P dose. The conversion is finished by Keff-value, which is an effective or effectiveness. But the Keff can not be measured directly for each sample and only the external radiative efficiency K3.7 can be measured. In order to obtain the Keff a special study for the conversion factor of Keff to K3.t has been made using the ultrathin TLD. The results show that the conversion factor of tile TLD for archaeological samples is 0.847, which is in agreement with calculated value 0.85.展开更多
Bacterial production is one of the key parameters to evaluate bacterial role in ocean carbon fluxes.Estimation of bacterial production requires the leucine-to-carbon conversion factors that change widely across enviro...Bacterial production is one of the key parameters to evaluate bacterial role in ocean carbon fluxes.Estimation of bacterial production requires the leucine-to-carbon conversion factors that change widely across environments.However,empirical leucine-to-carbon conversion factors(e CFs) are seldom determined in situ because of time consuming and little is known on regulating factors for the e CFs.During May 2015 to January 2016,fourteen dilution experiments were conducted,from the Zhujiang(Pearl River) Estuary to the coast of the northern South China Sea,to determine spatiotemporal variability in the e CFs and its potential controlling factors along an environmental gradient.The e CFs showed clear spatial variations with the highest(1.27–1.69(kg C)/(mol Leu)) in low salinity waters(salinity〈15),intermediate(1.03–1.25(kg C)/(mol Leu)) in moderate salinity(salinity of 15–25),and the lowest(0.48–0.85(kg C)/(mol Leu)) in high salinity waters(salinity〉25).Substrate availability was responsible for spatial variability in the e CFs.In the pristine coastal waters,low e CFs was related to substrate limitation and leucine incorporated was respired to maximize the survival rather than bacterial production.Hence,the e CFs measurement was needed for estimating bacterial production accurately in various marine environments.展开更多
In recent years,production and processing of natural selenium-rich agricultural products has become a research hotspot. The main factor affecting the selenium content in plant is the content of effective selenium in s...In recent years,production and processing of natural selenium-rich agricultural products has become a research hotspot. The main factor affecting the selenium content in plant is the content of effective selenium in soil. So it is important to understand the form and conversion relationship of selenium in soil and find ways to improve selenium effectiveness. By summarizing the researches on selenium at home and abroad,we analyze the classification of soil selenium form,the transformation among different selenium forms and the improving factors of selenium effectiveness. We understand the relationship between chemical form and extraction form of selenium,analyze the driving factors of conversion among different forms,and discuss the ways to improve selenium effectiveness of soil in high selenium-rich area. By combining characteristics of soil and crop in different selenium-rich regions,different selenium activation methods are used,which could provide more scientific evidence for further selenium research.展开更多
Despite decades of research on marine algae, there are still significant gaps in basic knowledge about chemical composition of these organisms, especially in tropical environments. In this study, the amino acid compos...Despite decades of research on marine algae, there are still significant gaps in basic knowledge about chemical composition of these organisms, especially in tropical environments. In this study, the amino acid composition and contents of total nitrogen, phosphorus, lipid, carbohydrate and protein were determined in Asparagopsis taxiformis, Centroceras clavulatum, Chaetomorpha aerea, Sargassum filipendula and Spyridia hypnoides. The seaweeds showed low lipid contents (lower than 5.5% d.w. in all species) and were rich in carbohydrates (more than 16% d.w. in all seaweeds). The percentage of nitrogen, phosphorus and protein varied widely among species, which red algae showed the highest con-centrations. The amino acid composition was similar among the seaweeds, which glutamic acid, aspartic acid and leu-cine as the most abundant. All species are poor in histidine. An average of 24.2% of the total nitrogen is non-proteinaceous. From data of total amino acid and total nitrogen, specific nitrogen-to-protein conversion factors were calculated for each species. The nitrogen-to-protein conversion factors calculated ranged from 4.51 to 5.21, with an overall average of 4.86. These findings show that the traditional conversion factor of 6.25 should be avoided for seaweeds, since it overestimates the actual protein content.展开更多
Through the method of literature analysis,this paper analyzes the present situation of the"non-grain conversion"of cultivated land in the transfer of agricultural land in China,summarizes the influencing fac...Through the method of literature analysis,this paper analyzes the present situation of the"non-grain conversion"of cultivated land in the transfer of agricultural land in China,summarizes the influencing factors and consequences of the phenomenon of"non-grain conversion"of cultivated land in the transfer of agricultural land,and finally puts forward some measures.The study found that costs and benefits are the fundamental factors affecting the"non-grain conversion"of cultivated land in agricultural land transfer,and other main factors include government and policy guidance,industrial and commercial capital to the countryside,labor transfer and so on.The"non-grain conversion"of cultivated land in the transfer of agricultural land is a serious threat to China s food security,leading to the decline of the quality of agricultural land and the destruction of the ecological environment,as well as the risk of breach of contract in"industrial and commercial capital to the countryside".Based on the understanding of the influencing factors of non-grain conversion,this paper puts forward the following measures:strengthening the control of the use of cultivated land in agricultural land transfer;implementing accurate subsidies for grain cultivation and ensuring the benefit of grain growers;adopting grain planting incentive mechanism to increase grain enthusiasm;strengthening media publicity and education to enhance food security awareness.The improvement of the current situation of the"non-grain conversion"of cultivated land in the transfer of agricultural land will be of great significance to the protection of agricultural land and food security in China.展开更多
The principle of single to single phase matrix electric power conversioin is further studied and the conversioin switch function is introduced into conventional rectifier inverter, thus a general character of the t...The principle of single to single phase matrix electric power conversioin is further studied and the conversioin switch function is introduced into conventional rectifier inverter, thus a general character of the two conversion techniques is discovered. It is characteristic of the switch functiion to follow mains voltage distortion and mains frequency drift. By utilizing the merit, unidirectional switch duty rations of the inverter follow the variation of DC link voltage automatically, thus the size of DC link electrolytic capacitor can be reduced considerably, bringing about improved mains side power factor. Corresponding topologies and theoretical and theoretical derivations are given, and so are the simulation results, based on which it is confirmed that the single to single phase matrix conversion technique is potentially useful in large scale production, and the introduction of switch function can yield good economic returns.展开更多
Oral English is always a difficult part for Chinese students,some can speak several sentences while not clearly know others’saying;others can understand the speakers’words while not express their own meaning fluentl...Oral English is always a difficult part for Chinese students,some can speak several sentences while not clearly know others’saying;others can understand the speakers’words while not express their own meaning fluently.This paper will focus on what factors influences the college students’spoken English by the specific experiment and SPSS app,whose data shows four ones,namely Language Monitor,Meaning Negotiation,Turn Taking and Empathetic Exchange.Thus,the paper takes conclusions and poses some suggestions to oral English teaching according to the affecting causes.It is expecting to help improve the ability of the oral English Conversation for Chinese College students.展开更多
Photogalvanic cells are photoelectrochemical cells chargeable in light for solar energy conversion and storage. They may be energy source for the future, if their electrical performance is increased. In this study, a ...Photogalvanic cells are photoelectrochemical cells chargeable in light for solar energy conversion and storage. They may be energy source for the future, if their electrical performance is increased. In this study, a photosensitizer Lissamine green B, a reductant Ascorbic acid and a surfactant NaLS have been used in the photogalvanic cell. The generated photopotential and photocurrent are 850.0 mV and 375.0 μA respectively. The conversion efficiency of the cell, fill factor and the cell performance were observed 1.0257%, 0.2598% and 170.0 minutes in dark respectively. The effects of different parameters on the electrical output of the photogalvanic cell were observed. A mechanism was proposed for the photogeneration of electrical energy.展开更多
Luan River is the main water source in Beijing-Tianjin-Hebei region,northern China,where the groundwater system is vulnerable and pollution issue is serious.It is significant for regional groundwater resources protect...Luan River is the main water source in Beijing-Tianjin-Hebei region,northern China,where the groundwater system is vulnerable and pollution issue is serious.It is significant for regional groundwater resources protection to identify the hydrogeochemistry evolution and affecting factors along flow direction occurred in the upper reaches,especially the surface water-groundwater(SWGW)conversion relationship.In this study,recharge,conversion and geochemistry evolution of SW and GW were elucidated based on physical-hydrochemical indicators and stable isotopes in 36 GW samples and 20 SW samples,which were collected in July 2019 and July 2020.The factor analysis was further utilized to determine the main factors responsible for regional hydrogeochemical evolution.Results indicate that GW recharged SW in plateau area,and SW and GW recharged each other in typical Alpine valley area.The hydrochemical types are HCO3-Ca·Mg and HCO3-Ca,and the hydrochemical evolution is dominated by weathering of silicate and carbonate minerals.The cation exchange adsorption has minor impact on groundwater hydrochemistry.The rise of SO42-and NO3-contents in groundwater is related to industrial and agricultural activities.The main controlling factors of SW hydrochemical components included recharge from groundwater,industrial and mining activities,explaining 90.04%of data variance.However,water-rock interaction,agricultural and domestic sewage are responsible for GW quality,accounting for 83.38%.展开更多
文摘This paper provides guidance for the quantification and reporting of blue carbon removals in the temperate coastal ecosystems,“Italian valli da pesca”or H.C.W.(Human Controlled Wetland,Lat.45°Lon.12°),where some pools as seagrasses,and salt marshes,are highly efficient at capturing and storing carbon dioxide(CO_(2))from the atmosphere.Halophyte salt marsh plants were found to have a%C on Dry Weight(D.W.)of 32.26±3.91(mean±standard deviation),macrophytes 33.65±7.99,seagrasses 29.23±2.23,tamarisk 48.42±2.80,while the first 5 centimetres of wetland mud,on average,had a%C of 8.56±0.94.Like the ISO(International Organization for Standardization)14064 guideline to quantify the GHG(Greenhouse Gas)emission,we have studied the different conversion factors to be used as a practical tool for measurement the CO_(2)sink activity.These factors are essential to calculate the overall carbon reduction in a project located in temperate wetland using a method as the ISO 14064.2,UNI-BNeutral,VCS VERRA or other that will come.
基金supported by the Charles H.“Skip”Smith Endowment Fund and the Verne M.Willaman Endowment Fund from the Pennsylvania State University to G.C。
文摘Objective:Glioblastoma(GBM)is the most prevalent and aggressive adult primary cancer in the central nervous system.Therapeutic approaches for GBM treatment are under intense investigation,including the use of emerging immunotherapies.Here,we propose an alternative approach to treat GBM through reprogramming proliferative GBM cells into non-proliferative neurons.Methods:Retroviruses were used to target highly proliferative human GBM cells through overexpression of neural transcription factors.Immunostaining,electrophysiological recording,and bulk RNA-seq were performed to investigate the mechanisms underlying the neuronal conversion of human GBM cells.An in vivo intracranial xenograft mouse model was used to examine the neuronal conversion of human GBM cells.Results:We report efficient neuronal conversion from human GBM cells by overexpressing single neural transcription factor Neurogenic differentiation 1(Neuro D1),Neurogenin-2(Neurog2),or Achaete-scute homolog 1(Ascl1).Subtype characterization showed that the majority of Neurog2-and Neuro D1-converted neurons were glutamatergic,while Ascl1 favored GABAergic neuron generation.The GBM cell-converted neurons not only showed pan-neuronal markers but also exhibited neuron-specific electrophysiological activities.Transcriptome analyses revealed that neuronal genes were activated in glioma cells after overexpression of neural transcription factors,and different signaling pathways were activated by different neural transcription factors.Importantly,the neuronal conversion of GBM cells was accompanied by significant inhibition of GBM cell proliferation in both in vitro and in vivo models.Conclusions:These results suggest that GBM cells can be reprogrammed into different subtypes of neurons,leading to a potential alternative approach to treat brain tumors using in vivo cell conversion technology.
文摘In the fine-grain TL dating the full o dose must be converted into the equivalent P dose. The conversion is finished by Keff-value, which is an effective or effectiveness. But the Keff can not be measured directly for each sample and only the external radiative efficiency K3.7 can be measured. In order to obtain the Keff a special study for the conversion factor of Keff to K3.t has been made using the ultrathin TLD. The results show that the conversion factor of tile TLD for archaeological samples is 0.847, which is in agreement with calculated value 0.85.
基金The National Key Research and Development Program under contract No.2016YFA0601203the National Natural Science Foundation of China under contract Nos 41476137 and 41676075+1 种基金the Project of State Key Laboratory of Tropical Oceanography under contract No.LTOZZ1504-1the Hundred Talent Program of Chinese Academy of Sciences under contract No.Y35L041001
文摘Bacterial production is one of the key parameters to evaluate bacterial role in ocean carbon fluxes.Estimation of bacterial production requires the leucine-to-carbon conversion factors that change widely across environments.However,empirical leucine-to-carbon conversion factors(e CFs) are seldom determined in situ because of time consuming and little is known on regulating factors for the e CFs.During May 2015 to January 2016,fourteen dilution experiments were conducted,from the Zhujiang(Pearl River) Estuary to the coast of the northern South China Sea,to determine spatiotemporal variability in the e CFs and its potential controlling factors along an environmental gradient.The e CFs showed clear spatial variations with the highest(1.27–1.69(kg C)/(mol Leu)) in low salinity waters(salinity〈15),intermediate(1.03–1.25(kg C)/(mol Leu)) in moderate salinity(salinity of 15–25),and the lowest(0.48–0.85(kg C)/(mol Leu)) in high salinity waters(salinity〉25).Substrate availability was responsible for spatial variability in the e CFs.In the pristine coastal waters,low e CFs was related to substrate limitation and leucine incorporated was respired to maximize the survival rather than bacterial production.Hence,the e CFs measurement was needed for estimating bacterial production accurately in various marine environments.
基金Supported by Guangxi Science Research and Technology Development Plan Program(Guikehe 415104001-22)the National Natural Science Foundation of China(41761052)+2 种基金Major Project of Guangxi Innovation Driven(Guike AA17202019-1,Guike AA17202019-2,Guike AA17202026-2)Guangxi Youth Foundation Project(2016GXNSFBA380131)Science and Technology Development Fund Project of Guangxi Academy of Agricultural Sciences(Guinongke 2017JM01,Guinongke 2017JM03,Guinongke 2015JM23)
文摘In recent years,production and processing of natural selenium-rich agricultural products has become a research hotspot. The main factor affecting the selenium content in plant is the content of effective selenium in soil. So it is important to understand the form and conversion relationship of selenium in soil and find ways to improve selenium effectiveness. By summarizing the researches on selenium at home and abroad,we analyze the classification of soil selenium form,the transformation among different selenium forms and the improving factors of selenium effectiveness. We understand the relationship between chemical form and extraction form of selenium,analyze the driving factors of conversion among different forms,and discuss the ways to improve selenium effectiveness of soil in high selenium-rich area. By combining characteristics of soil and crop in different selenium-rich regions,different selenium activation methods are used,which could provide more scientific evidence for further selenium research.
基金Authors are indebted to Brazil’s National Council for Scientific and Technological Development(CNPq)and Research Support Foundation of Rio de Janeiro State(FAPERJ)for the financial support of this studyGDS thanks Coordination of Improvement of Higher Education Personnel(CAPES)for her scholarshipAuthors thank Dr.Renato Crespo Pereira(UFF)for the use of labora-tory facilities and to Dr.Joel C.De-Paula(UNIRIO)for confirming the identification of the seaweeds.
文摘Despite decades of research on marine algae, there are still significant gaps in basic knowledge about chemical composition of these organisms, especially in tropical environments. In this study, the amino acid composition and contents of total nitrogen, phosphorus, lipid, carbohydrate and protein were determined in Asparagopsis taxiformis, Centroceras clavulatum, Chaetomorpha aerea, Sargassum filipendula and Spyridia hypnoides. The seaweeds showed low lipid contents (lower than 5.5% d.w. in all species) and were rich in carbohydrates (more than 16% d.w. in all seaweeds). The percentage of nitrogen, phosphorus and protein varied widely among species, which red algae showed the highest con-centrations. The amino acid composition was similar among the seaweeds, which glutamic acid, aspartic acid and leu-cine as the most abundant. All species are poor in histidine. An average of 24.2% of the total nitrogen is non-proteinaceous. From data of total amino acid and total nitrogen, specific nitrogen-to-protein conversion factors were calculated for each species. The nitrogen-to-protein conversion factors calculated ranged from 4.51 to 5.21, with an overall average of 4.86. These findings show that the traditional conversion factor of 6.25 should be avoided for seaweeds, since it overestimates the actual protein content.
文摘Through the method of literature analysis,this paper analyzes the present situation of the"non-grain conversion"of cultivated land in the transfer of agricultural land in China,summarizes the influencing factors and consequences of the phenomenon of"non-grain conversion"of cultivated land in the transfer of agricultural land,and finally puts forward some measures.The study found that costs and benefits are the fundamental factors affecting the"non-grain conversion"of cultivated land in agricultural land transfer,and other main factors include government and policy guidance,industrial and commercial capital to the countryside,labor transfer and so on.The"non-grain conversion"of cultivated land in the transfer of agricultural land is a serious threat to China s food security,leading to the decline of the quality of agricultural land and the destruction of the ecological environment,as well as the risk of breach of contract in"industrial and commercial capital to the countryside".Based on the understanding of the influencing factors of non-grain conversion,this paper puts forward the following measures:strengthening the control of the use of cultivated land in agricultural land transfer;implementing accurate subsidies for grain cultivation and ensuring the benefit of grain growers;adopting grain planting incentive mechanism to increase grain enthusiasm;strengthening media publicity and education to enhance food security awareness.The improvement of the current situation of the"non-grain conversion"of cultivated land in the transfer of agricultural land will be of great significance to the protection of agricultural land and food security in China.
文摘The principle of single to single phase matrix electric power conversioin is further studied and the conversioin switch function is introduced into conventional rectifier inverter, thus a general character of the two conversion techniques is discovered. It is characteristic of the switch functiion to follow mains voltage distortion and mains frequency drift. By utilizing the merit, unidirectional switch duty rations of the inverter follow the variation of DC link voltage automatically, thus the size of DC link electrolytic capacitor can be reduced considerably, bringing about improved mains side power factor. Corresponding topologies and theoretical and theoretical derivations are given, and so are the simulation results, based on which it is confirmed that the single to single phase matrix conversion technique is potentially useful in large scale production, and the introduction of switch function can yield good economic returns.
文摘Oral English is always a difficult part for Chinese students,some can speak several sentences while not clearly know others’saying;others can understand the speakers’words while not express their own meaning fluently.This paper will focus on what factors influences the college students’spoken English by the specific experiment and SPSS app,whose data shows four ones,namely Language Monitor,Meaning Negotiation,Turn Taking and Empathetic Exchange.Thus,the paper takes conclusions and poses some suggestions to oral English teaching according to the affecting causes.It is expecting to help improve the ability of the oral English Conversation for Chinese College students.
文摘Photogalvanic cells are photoelectrochemical cells chargeable in light for solar energy conversion and storage. They may be energy source for the future, if their electrical performance is increased. In this study, a photosensitizer Lissamine green B, a reductant Ascorbic acid and a surfactant NaLS have been used in the photogalvanic cell. The generated photopotential and photocurrent are 850.0 mV and 375.0 μA respectively. The conversion efficiency of the cell, fill factor and the cell performance were observed 1.0257%, 0.2598% and 170.0 minutes in dark respectively. The effects of different parameters on the electrical output of the photogalvanic cell were observed. A mechanism was proposed for the photogeneration of electrical energy.
基金funded by the Ecological Civilization Demonstration Area Comprehensive Geological Survey Project“Hydrogeological Survey of Chengde Area”(No.DD20200522)the National Natural Science Foundation of China(Nos.41521001 and 42177078)the“111”Program of China(No.B18049).
文摘Luan River is the main water source in Beijing-Tianjin-Hebei region,northern China,where the groundwater system is vulnerable and pollution issue is serious.It is significant for regional groundwater resources protection to identify the hydrogeochemistry evolution and affecting factors along flow direction occurred in the upper reaches,especially the surface water-groundwater(SWGW)conversion relationship.In this study,recharge,conversion and geochemistry evolution of SW and GW were elucidated based on physical-hydrochemical indicators and stable isotopes in 36 GW samples and 20 SW samples,which were collected in July 2019 and July 2020.The factor analysis was further utilized to determine the main factors responsible for regional hydrogeochemical evolution.Results indicate that GW recharged SW in plateau area,and SW and GW recharged each other in typical Alpine valley area.The hydrochemical types are HCO3-Ca·Mg and HCO3-Ca,and the hydrochemical evolution is dominated by weathering of silicate and carbonate minerals.The cation exchange adsorption has minor impact on groundwater hydrochemistry.The rise of SO42-and NO3-contents in groundwater is related to industrial and agricultural activities.The main controlling factors of SW hydrochemical components included recharge from groundwater,industrial and mining activities,explaining 90.04%of data variance.However,water-rock interaction,agricultural and domestic sewage are responsible for GW quality,accounting for 83.38%.