Modeling and reasoning on domain contexts play a key role for adding intelligence to communication services, and the approach of capability-based requirement engineering ensures the scientificity and accuracy of requi...Modeling and reasoning on domain contexts play a key role for adding intelligence to communication services, and the approach of capability-based requirement engineering ensures the scientificity and accuracy of requirement elicitation. This paper presents a capability-based context ontology modeling approach for command and control, communication, computer, intelligence, surveillance and reconnaissance(C^4ISR) communication. Primarily, a capability-based C^4ISR communication meta-concept model and a C^4ISR communication context meta-ontology are constructed. The context ontology is established under the constraints of the C^4ISR communication context meta-ontology, and furthermore, algorithms are proposed to support context reasoning based on description logic. A case study is presented to demonstrate applicability of the proposed method.展开更多
Objective: To compare carotid catheters blooddrawing and tail-cut blooddrawing in traumatizing rats and changing their intemal L-selectin. Methods: Two ways of bloodletting were selected to produce hemorrhagic shock...Objective: To compare carotid catheters blooddrawing and tail-cut blooddrawing in traumatizing rats and changing their intemal L-selectin. Methods: Two ways of bloodletting were selected to produce hemorrhagic shock models. Monoclonal antibody sign and flow cytometer were used to test neutrophil L-selectin dynamic expression in rats. Results: No remarkable differences were shown among different time points in neutrophil L-selectin expressing amount ( average fluorescence index) ( P 〉 0.05). Compared with the normal control group, all cell surface expressions in empirical control group increased. Cell surface expressions reached the summit at 3 hours and kept the high level at 4-5 hours. A progressive increase of the mRNA expression peaked at 5 hours; the expressions in both groups of carotid catheters blooddrawing increased compared with normal control group, and remained stable after 3 hours compared with the Tail-cut Blooddrawing Group. Conclusion: L-sclectin expressions changed little in tail-cut blooddrawing rats, while carotid catheters resulted moderate or sever trauma. Therefore, it was suggested that it should not be set as hemorrhagic shock control model. As neutrophil L-selection expressions increased after trauma, the adhesion of leucocytes to the venule wall may be beneficial to the healing of wound and enhance the ability of anti-infection. The immediate increasing of neutrophil surface L-selectin expressions in this study was likely due to the direct release of Lselectin from cytoplasm granules that do not depend on protein synthesis.展开更多
Aims Forest disturbance from extreme weather events due to climate change could increase the contribution of fresh green leaves to the litter layer of soil and subsequently alter the composition and activity of the so...Aims Forest disturbance from extreme weather events due to climate change could increase the contribution of fresh green leaves to the litter layer of soil and subsequently alter the composition and activity of the soil microbial properties and soil carbon cycling.The objective of this study was to compare the effect of naturally fallen litter and fresh leaves on the soil microbial community composition and their activities.Methods Fresh leaves and normal fallen litter were collected from four tree species(Pinus elliottii,Schima superba,Acacia mangium,A.auriculaeformis)in subtropical China and mixed with soil.Soil microbial community composition was determined using PLFAs,and its activity was quantified by soil respiration.During a 12-month period,the decomposition rate of litter was measured bimonthly using a litterbag method.Soil microbial samples were collected after 6 and 12 months.Soil respiration was measured monthly.Important Findings We found that fresh leaves decomposed faster than their conspecific fallen litter.Although total microbial biomass and bacterial biomass were similar among treatments,soil fungal biomass was higher in fresh leaf than fallen litter treatments,resulting in greater values of the Fungal phospholipid fatty acids(PLFAs)/Bacterial PLFAs ratio.Fungal PLFA values were greater for Schima superba than the other species.The effect of litter type on soil respiration was species-dependent.Specifically,fallen litter released 35%more CO_(2) than fresh leaves of the conifer P.elliottii.The opposite pattern was observed in the broadleaf species whose fresh leaf treatments emitted 17%–32%more CO_(2) than fallen litter.Given future predictions that global climate change will cause more disturbances to forests,these results indicate that conifer and broadleaf forests in subtropical China may respond differently to increased fresh litter inputs,with net soil microbial respiration decreasing in conifer forests and increasing in broadleaf forests.展开更多
Background:Forest succession is an important ecological process and has been studied for more than a century.However,changes in nitrogen(N)availability during succession remain unclear as they may lead to either N sat...Background:Forest succession is an important ecological process and has been studied for more than a century.However,changes in nitrogen(N)availability during succession remain unclear as they may lead to either N satura-tion or N limitation.Here,we propose a conceptual model to illustrate changes in N availability during four stages of secondary succession using the natural abundance of ^(15) N in plant leaves(foliarδ^(15)N).We predicted that N availability would decline in the early stages of succession and then increase in late stages,coinciding with the changes in foliarδ^(15)N,with the inflection point varying in different climate zones.Data on foliarδ^(15)N from 16 succession sequences were synthesized to explore changes in N availability during forest succession.Results:The compiled data were consistent with the proposed conceptual model.Foliarδ^(15)N in boreal and temperate forests decreased significantly in the first two stages of succession(estimated to last at least 66 years in temperate forests),at a rate of 0.18‰and 0.38‰per decade,respectively,and decreased slightly in tropical forests in the first 23 years.Foliarδ^(15)N is projected to increase in later stages in all forests,which is supported by observations in both temperate and tropical forests.The inflection points of N availability when N limitation peaked during succession were different in different climate zones,implying different ecosystem N turnovers.Conclusions:Our study reconciles the controversies regarding changes in N availability during forest secondary succession.Our findings are also useful for predicting the recovery of N and carbon accumulation during succession.Nonetheless,studies on forest secondary succession using foliarδ^(15)N have thus far been limited,and more research should be conducted to further verify the conceptual model proposed here.展开更多
基金supported by the National Natural Science Foundation of China(61273210)
文摘Modeling and reasoning on domain contexts play a key role for adding intelligence to communication services, and the approach of capability-based requirement engineering ensures the scientificity and accuracy of requirement elicitation. This paper presents a capability-based context ontology modeling approach for command and control, communication, computer, intelligence, surveillance and reconnaissance(C^4ISR) communication. Primarily, a capability-based C^4ISR communication meta-concept model and a C^4ISR communication context meta-ontology are constructed. The context ontology is established under the constraints of the C^4ISR communication context meta-ontology, and furthermore, algorithms are proposed to support context reasoning based on description logic. A case study is presented to demonstrate applicability of the proposed method.
文摘Objective: To compare carotid catheters blooddrawing and tail-cut blooddrawing in traumatizing rats and changing their intemal L-selectin. Methods: Two ways of bloodletting were selected to produce hemorrhagic shock models. Monoclonal antibody sign and flow cytometer were used to test neutrophil L-selectin dynamic expression in rats. Results: No remarkable differences were shown among different time points in neutrophil L-selectin expressing amount ( average fluorescence index) ( P 〉 0.05). Compared with the normal control group, all cell surface expressions in empirical control group increased. Cell surface expressions reached the summit at 3 hours and kept the high level at 4-5 hours. A progressive increase of the mRNA expression peaked at 5 hours; the expressions in both groups of carotid catheters blooddrawing increased compared with normal control group, and remained stable after 3 hours compared with the Tail-cut Blooddrawing Group. Conclusion: L-sclectin expressions changed little in tail-cut blooddrawing rats, while carotid catheters resulted moderate or sever trauma. Therefore, it was suggested that it should not be set as hemorrhagic shock control model. As neutrophil L-selection expressions increased after trauma, the adhesion of leucocytes to the venule wall may be beneficial to the healing of wound and enhance the ability of anti-infection. The immediate increasing of neutrophil surface L-selectin expressions in this study was likely due to the direct release of Lselectin from cytoplasm granules that do not depend on protein synthesis.
基金National Natural Science Foundation of China(30870442)National Basic Research Program of China(2009CB421101 and 2011CB403200)+3 种基金NSFC-Guangdong Joint Project(U1131001)Guangdong Natural Science Foundation(S2011040005712)the Knowledge Innovation Program of the Chinese Academy of Sciences(KSCX2-EW-J-28)the‘Strategic Priority Research Program-Climate Change:Carbon Budget and Related Issues’of the Chinese Academy of Sciences(XDA05070307).
文摘Aims Forest disturbance from extreme weather events due to climate change could increase the contribution of fresh green leaves to the litter layer of soil and subsequently alter the composition and activity of the soil microbial properties and soil carbon cycling.The objective of this study was to compare the effect of naturally fallen litter and fresh leaves on the soil microbial community composition and their activities.Methods Fresh leaves and normal fallen litter were collected from four tree species(Pinus elliottii,Schima superba,Acacia mangium,A.auriculaeformis)in subtropical China and mixed with soil.Soil microbial community composition was determined using PLFAs,and its activity was quantified by soil respiration.During a 12-month period,the decomposition rate of litter was measured bimonthly using a litterbag method.Soil microbial samples were collected after 6 and 12 months.Soil respiration was measured monthly.Important Findings We found that fresh leaves decomposed faster than their conspecific fallen litter.Although total microbial biomass and bacterial biomass were similar among treatments,soil fungal biomass was higher in fresh leaf than fallen litter treatments,resulting in greater values of the Fungal phospholipid fatty acids(PLFAs)/Bacterial PLFAs ratio.Fungal PLFA values were greater for Schima superba than the other species.The effect of litter type on soil respiration was species-dependent.Specifically,fallen litter released 35%more CO_(2) than fresh leaves of the conifer P.elliottii.The opposite pattern was observed in the broadleaf species whose fresh leaf treatments emitted 17%–32%more CO_(2) than fallen litter.Given future predictions that global climate change will cause more disturbances to forests,these results indicate that conifer and broadleaf forests in subtropical China may respond differently to increased fresh litter inputs,with net soil microbial respiration decreasing in conifer forests and increasing in broadleaf forests.
基金supported by National Key Research and Development Program of China(No.2016YFA0600802)K.C.Wong Education Foundation(GJTD-2018–07)+1 种基金Liaoning Vitalization Talents Program(XLYC1902016)the National Natural Science Foundation of China(41773094,31901134)。
文摘Background:Forest succession is an important ecological process and has been studied for more than a century.However,changes in nitrogen(N)availability during succession remain unclear as they may lead to either N satura-tion or N limitation.Here,we propose a conceptual model to illustrate changes in N availability during four stages of secondary succession using the natural abundance of ^(15) N in plant leaves(foliarδ^(15)N).We predicted that N availability would decline in the early stages of succession and then increase in late stages,coinciding with the changes in foliarδ^(15)N,with the inflection point varying in different climate zones.Data on foliarδ^(15)N from 16 succession sequences were synthesized to explore changes in N availability during forest succession.Results:The compiled data were consistent with the proposed conceptual model.Foliarδ^(15)N in boreal and temperate forests decreased significantly in the first two stages of succession(estimated to last at least 66 years in temperate forests),at a rate of 0.18‰and 0.38‰per decade,respectively,and decreased slightly in tropical forests in the first 23 years.Foliarδ^(15)N is projected to increase in later stages in all forests,which is supported by observations in both temperate and tropical forests.The inflection points of N availability when N limitation peaked during succession were different in different climate zones,implying different ecosystem N turnovers.Conclusions:Our study reconciles the controversies regarding changes in N availability during forest secondary succession.Our findings are also useful for predicting the recovery of N and carbon accumulation during succession.Nonetheless,studies on forest secondary succession using foliarδ^(15)N have thus far been limited,and more research should be conducted to further verify the conceptual model proposed here.