Atmospheric CO_(2)concentration is elevated globally,which has“CO_(2)fertilization effects”and potentially improves plant photosynthesis,yield,and productivity.Despite the beneficial effect of CO_(2)fertilization be...Atmospheric CO_(2)concentration is elevated globally,which has“CO_(2)fertilization effects”and potentially improves plant photosynthesis,yield,and productivity.Despite the beneficial effect of CO_(2)fertilization being modulated by vapor pressure deficit(VPD),the underlying mechanism is highly uncertain.In the present study,the potential roles of hormones in determining CO_(2)fertilization effects under contrasting high and low VPD conditions were investigated by integrated physiological and transcriptomic analyses.Beneficial CO_(2)fertilization effects were offset under high VPD conditions and were constrained by plant water stress and photosynthetic CO_(2)utilization.High VPD induced a large passive water driving force,which disrupted the water balance and consequently caused plant water deficit.Leaf water potential,turgor pressure,and hydraulic conductance declined under high VPD stress.The physiological evidence combined with transcriptomic analyses demonstrated that abscisic acid(ABA)and jasmonic acid(JA)potentially acted as drought-signaling molecules in response to high VPD stress.Increased foliar ABA and JA content triggered stomatal closure to prevent excessive water loss under high VPD stress,which simultaneously increased the diffusion resistance for CO_(2)uptake from atmosphere to leaf intercellular space.High VPD also significantly increased mesophyll resistance for CO_(2)transport from stomatal cavity to fixation site inside chloroplast.The chloroplast“sink”CO_(2)availability was constrained by stomatal and mesophyll resistance under high VPD stress,despite the atmospheric“source”CO_(2)concentration being elevated.Thus,ABA-and JA-mediated drought-resistant mechanisms potentially modified the beneficial effect of CO_(2)fertilization on photosynthesis,plant growth,and yield productivity.This study provides valuable information for improving the utilization efficiency of CO_(2)fertilization and a better understanding of the physiological processes.展开更多
The sambong (Blumea balsamifera (L.) DC.) leaf was investigated by applying frozen section and thin section technology, and observed through optical microscope. The results showed that the sambong leaf was firstly ori...The sambong (Blumea balsamifera (L.) DC.) leaf was investigated by applying frozen section and thin section technology, and observed through optical microscope. The results showed that the sambong leaf was firstly originated nearby the apical bud at the stem tip. The first leaf grows fast, that the mitosis happens frequently and the cytoplasm manufacture rapidly. The cells in the first few leaves have not yet differentiated into the spongy parenchyma and palisade parenchyma. In the mature leaf, the spongy parenchyma and palisade parenchyma were fully developed. The epidermal hairs were firstly developed on the abaxial side of the first leaf.展开更多
The plant growth regulator diethyl aminoethyl hexanoate (DA-6) has proved highly effective on micropropagation of the medicinal plant purple coneflower (Echinacea purpurea (L.) Moench), however, sharp variation of the...The plant growth regulator diethyl aminoethyl hexanoate (DA-6) has proved highly effective on micropropagation of the medicinal plant purple coneflower (Echinacea purpurea (L.) Moench), however, sharp variation of the effects existed among explants in the same treatment, making the application of DA-6 in micropropagation difficult. In order to clarify factors that influencing the treating results of DA-6, explants with different biomass dosage were prepared and inoculated onto medium supplemented with different concentrations of DA-6. It was found that among the three kinds of biomass dosage explants, the lowest biomass explants required the lowest concentration of DA-6, and the highest biomass explants required the highest concentration of DA-6 for the best results on adventitious buds regeneration. Similar results were obtained when regenerated buds of three different biomass dosages were cultured. It could be concluded from the above experimental results that for achieving better DA-6 application results, the concentration of DA-6 should be determined not only by the types but also by the biomass dosage of the explants. The present finding might help to improve the micropropagation efficiency in E. purpurea, and might be applicable for other species展开更多
Immature leaves and stems, which were about one to three centimeters nearby the stem tips, of Blumea balsamifera (L.) DC. (BB) and Blumea laciniata (Roxb.) DC. (BL) were cut into sections under ?18?C with a frozen sec...Immature leaves and stems, which were about one to three centimeters nearby the stem tips, of Blumea balsamifera (L.) DC. (BB) and Blumea laciniata (Roxb.) DC. (BL) were cut into sections under ?18?C with a frozen section machine, and observed under an optical microscope. Results show that the most significant difference is that the BB has only one kind of glandular trichomes, while the BL has two. The glandular trichomes found on BB terms were all short glandular hairs (SGH), which were not longer than 100 μm. On BL stems, besides the SGH, the long glandular hairs (LGH), which were longer than 200 μm, were also found. By the factors pointed out in present study, the BB and BL and be distinguished from each other.展开更多
Anthersisolated from tetraploid purple coneflowerplants were cultured in vitro. The highest callus induction rate was obtained when the medium was consisted of N6 basal elements, 4% sucrose, 0.5 mg?L?1 BA, and 0.10 mg...Anthersisolated from tetraploid purple coneflowerplants were cultured in vitro. The highest callus induction rate was obtained when the medium was consisted of N6 basal elements, 4% sucrose, 0.5 mg?L?1 BA, and 0.10 mg?L?1 NAA. Various morphogenesis such as globular, heart-shape, torpedo-shapeand final state embryos as well asvarious texture calluses around were observed. Out of 110 plantlets regenerated, 104 were confirmed as diploid and the rest were as tetraploid. Plants of one diploid offspring strain presented aspecialcharacter in pot: unlike the original tetraploid plants, it grown tubular, bisexual ray florets. The results obtained in the present studies indicated that although the tetraploid purple coneflower plants produced only diploid microspores, the recovery of some useful mutants through in vitro anther cultures might be reasonably expected.展开更多
Mannitol or sorbitol was added into the Murashige and Skoog (MS) medium contain-ing certain concentrations of 6-Benzyladenine (BA) which was used to induce adventi-tious buds of Echinacea purpurea L. Results showed th...Mannitol or sorbitol was added into the Murashige and Skoog (MS) medium contain-ing certain concentrations of 6-Benzyladenine (BA) which was used to induce adventi-tious buds of Echinacea purpurea L. Results showed that the induced adventitious buds growing from medium added with 15 g·L-1 mannitol or sorbitol of the same con-centration were more consistent in height. The regeneration rates in MS medium containing 0.2 mg·L-1 BA and 15 g·L-1 mannitol were increased, while in MS medium containing 0.2 and 0.5 mg·L-1 BA, and 15 g·L-1 sorbitol, the regeneration rates were suppressed. On the other hand, genotype of explants and the concentration of BA in-fluenced the incidence of hyperhydricity, and the hyperhydricity of regenerated buds was more severe when the petiole explants were inoculated on medium with 15 g·L-1 mannitol or 15 g·L-1 sorbitol. The present study offers new possibility to the production of uniform plantlets for commercial cultivation in this important medicinal plant.展开更多
[Objectives]This study was conducted to clarify the differences of volatile components in fresh fruit of Morinda citrifolia L.from different origins.[Methods]The method of HS-SPME-GC/MS detection was used to determine...[Objectives]This study was conducted to clarify the differences of volatile components in fresh fruit of Morinda citrifolia L.from different origins.[Methods]The method of HS-SPME-GC/MS detection was used to determine the volatile chemical components in fresh fruit of M.citrifolia.[Results]52,52 and 45 volatile components were identified from the fresh fruit of M.citrifolia from Xisha,Wanning and Haikou,respectively.Among them,the number and content of the identified esters were relatively high,mainly methyl caprylate,ethyl caprylate,4-pentenyl caproate,3-methylbuten-2-enyl caprylate,methyl caproate,and ethyl caproate.There were also fatty acids,alcohols,phenols,ketones,aldehydes and other substances.There were 33 common ingredients in the fruit from the three origins,mainly including caprylic acid,caproic acid,capric acid,methyl caprylate,ethyl caprylate,4-pentenyl caproate,3-methylbutene-2-enyl caprylate,methyl caproate,ethyl caproate,methyl caprate and hexyl caproate.[Conclusions]The types and contents of volatile components in fresh fruit of M.citrifolia from different origins were significantly different.展开更多
In order to meet the pressing demand for wide-area communication required by the Global Energy Interconnection(GEI),accelerating the construction of satellite-terrestrial Integra怕d networks that can achieve network e...In order to meet the pressing demand for wide-area communication required by the Global Energy Interconnection(GEI),accelerating the construction of satellite-terrestrial Integra怕d networks that can achieve network extension and seamless global coverage has become the focus of power communication tech no logy development.In this study,we propose a satellite-terrestrial integrated network model that can support interconnection and interoperation on the IP layer between the satellite system and the怕rrestrial segment of the existing power communication system.First,the composition and function of the satellite-terrestrial collaborative network are explained.Then,the IP-based protocol stack is described,and a typical applicati on experime nt is con ducted to illustrate the particular process of this protocol stack.Fin ally,a use case of IP interconn ection that depends on GEO satellite communication is detailed.The experime ntal study has showed that the satellite-terrestrial collaborative network can efficiently support various IP applications for the GEI.展开更多
[Objectives]This study was conducted to investigate the effects of magnesium on the yield of Blumea balsamifera(L.)DC.and the accumulation of primary metabolites that affect yield of the medicinal material.[Methods]Th...[Objectives]This study was conducted to investigate the effects of magnesium on the yield of Blumea balsamifera(L.)DC.and the accumulation of primary metabolites that affect yield of the medicinal material.[Methods]The annual seedlings of B.balsamifera were selected as experimental materials.The treatment concentrations of magnesium(Mg)were set as 0,1.5,15 and 150 mg/ml supplied by MgSO4·7H2O.The yield of the medicinal material was measured dynamically.And the content of total sugar was determined by 3,5-dinitrosalicylic acid colorimetry;the content of crude protein was determined by the Kjeldahl method;the ash content was determined by the high-temperature burning method;the crude fat content was determined with a crude fat instrument;and the crude fiber content was determined by the acid-base washing and weighing method.[Results]Mg significantly increased the yield of B.balsamifera medicinal material,especially 15 mg/ml Mg.It was found that in September,October and November,1.5 mg/ml and 15 mg/ml Mg significantly increased the contents of primary metabolites including total sugar,ash,crude protein,crude fat and crude fiber,and 150 mg/ml of Mg increased the accumulation of total sugar,ash,crude protein and crude fiber to different degrees,but had certain inhibitory effect on the accumulation of crude fat.In December,the application of Mg inhibited the accumulation of total sugar,ash and crude protein to different degrees,but significantly promoted the accumulation of crude fat and fiber.[Conclusions]This study provides a theoretical basis for clarifying the effects of different concentrations of magnesium on plant growth.展开更多
An extreme event may lead to serious disaster to a complex system.In an extreme event series there exist generally non-trivial patterns covering different time scales.Investigations on extreme events are currently bas...An extreme event may lead to serious disaster to a complex system.In an extreme event series there exist generally non-trivial patterns covering different time scales.Investigations on extreme events are currently based upon statistics,where the patterns are merged into averages.In this paper from extreme event series we constructed extreme value series and extreme interval series.And the visibility graph is then adopted to display the patterns formed by the increases/decreases of extreme value or interval faster/slower than the linear ones.For the fractional Brownian motions,the properties for the constructed networks are the persistence,threshold,and event-type-independent,e.g.,the degree distributions decay exponentially with almost identical speeds,the nodes cluster into modular structures with large and similar modularity degrees,and each specific network has a perfect hierarchical structure.For the volatilities of four stock markets(NSDQ,SZI,FTSE100,and HSI),the properties for the former three's networks are threshold-and market-independent.Comparing with the factional Brownian motions,their degree distributions decay exponentially but with slower speeds,their modularity behaviors are significant but with smaller modularity degrees.The fourth market behaves similar qualitatively but different quantitatively with the three markets.Interestingly,all the transition frequency networks share an identical backbone composed of nine edges and the linked graphlets.The universal behaviors give us a framework to describe extreme events from the viewpoint of network.展开更多
OBJECTIVE: To assess the effectiveness of violateoil from Blumea Balsamifera(L.) DC. leaves(BB oil)on wound healing in mice.METHODS: Undiluted BB oil and its diluted solutions with olive oil to 1/5 and 1/10 to yield B...OBJECTIVE: To assess the effectiveness of violateoil from Blumea Balsamifera(L.) DC. leaves(BB oil)on wound healing in mice.METHODS: Undiluted BB oil and its diluted solutions with olive oil to 1/5 and 1/10 to yield BB oil1/5and BB oil1/10 were applied to the wounded skin before wound healing conditions were assessed by healing rate, histopathology, and contents of collagen, hydroxyproline, and Neuropeptide Substance P(SP). All above results were compared with the efficacies of the control, pure olive oil, basic fibroblast growth factor(BFGF), and cream of Jing Wan Hong(JWH).RESULTS: BB oil1/5and BB oil1/10 improved wound contraction and closure. Histopathology study further confirmed a desirable histological organization of wound tissues. BB oil1/5and BB oil1/10 reduced the number of inflammatory cells, increased wound-healing rates, and significantly increased the hydroxyproline content. Both BB oil1/5and BB oil1/10 improved formation of collagen, and reduced the frequency of fibroblasts. Moreover, BB oil1/5and BB oil1/10 markedly promoted SP expression. However, undiluted BB oil may induce skin thickening and hardening, inhibite collagen synthesis and delay complete skin wound healing.CONCLUSION: The BB oil1/5and BB oil1/10 promoted capillary regeneration, blood circulation, collagen deposition, granular tissue formation, epithelial deposition, and wound contraction. The mechanism underlying the action might be related to induction of SP secretion, and the proliferation and differentiation of mesenchymal cells.展开更多
The versatile catechol unit of polydopamine (PDA) endows this molecule with a broad ranging adhesive properties and reducibility.We prepared free-standing PDA particles by a simple self-polymerization and these partic...The versatile catechol unit of polydopamine (PDA) endows this molecule with a broad ranging adhesive properties and reducibility.We prepared free-standing PDA particles by a simple self-polymerization and these particles served as both an effective reductant and scaffold for a hybrid catalyst.The raspberrylike nanocomposites featured a high density of AuNPs uniformly deposited on PDA particles (PDA@Au).This system was prepared in-situ with assistance from the active catechol and amine groups of the PDA particles.To quantify the effect of the PDA carriers,we studied the catalytic activity of the PDA and PDA@Au particles.The PDA particles showed a pronounced charge-dependent catalytic activity for reduction of cationic methylene blue,negatively-charged 4-nitrophenolate,and zwitterionic rhodamine B in the presence of borohydride,whereas PDA@AuNPs showed catalytic activity with a less pronounced charge-dependence of the catalytic efficiency of the AuNPs.The PDA particles served as a redox mediator and adsorbent accelerator in degradation of the dyes owing to its unique chemical structure.展开更多
Introduction of iodosylarnes into biomimetic nonheme chemistry has made great achievement on identification of the subtle metal-oxygen reaction intermediates. However, after more than three decades of experimental and...Introduction of iodosylarnes into biomimetic nonheme chemistry has made great achievement on identification of the subtle metal-oxygen reaction intermediates. However, after more than three decades of experimental and theoretical efforts the nature of the metal-iodosylarene adducts and the related dichotomous one-oxidant/multiple-oxident controversy have remained a matter of speculation. Herein, we report a theoretical study of the structure-activity relationship of the noted iron(Ⅲ)-iodsylarene complex,FeⅢ(Ph IO)(OTf)3(1), in oxygenation of cyclohexene. The calculated results revealed that 1 behaves like a chameleon by adapting its roles as a 2 e-oxidant or an oxygen donor, as a response to the regioselective attack of the C–H bond and the C=C bond. The oxidative C–H bond activation by 1 was found, for the first time, to proceed via a novel hydride transfer process to form a cyclohexene carbonium intermediate,such non-rebound step triggers the Ritter reaction to uptake an acetonitrile molecule to form the amide product, or proceeds with the rebound of the hydroxyl group return to the solvent cage to form the hydroxylated product. While in the C=C bond activation, 1 is a normal oxygen donor and shows two-state reactivity to present the epoxide product via a direct oxygen atom transfer mechanism. These mechanistic findings fit and explain the famous Valentine’s experiments and enrich the non-rebound scenario in bioinorganic chemistry.展开更多
In order to meet the needs of new materials gradually developing towards miniaturization,integration,and light weight,multifunctional BaNb_(2)O_(6):Yb^(3+)/Er^(3+)/Tm^(3+)transparent glass-ceramics were success-fully ...In order to meet the needs of new materials gradually developing towards miniaturization,integration,and light weight,multifunctional BaNb_(2)O_(6):Yb^(3+)/Er^(3+)/Tm^(3+)transparent glass-ceramics were success-fully prepared by melt quenching and controllable crystallization.Its structure,luminescence,and en-ergy transmission were studied.Using the opposite temperature dependence of the Tm^(3+)emission band and the corresponding large energy level gap,a maximum relative sensitivity of 2.3%K^(-1)based on thermal coupling levels(TCLs)is obtained in a wide temperature range(298-673 K).The multi-ratio optical thermometry based on TCLs and non-TCLs is successfully realized by using the different emission bands of double emission centers,which makes it possible for self-reference optical temperature measurement modes.In addition,the transparent glass-ceramic exhibits excellent electrical properties under 700 kV cm^(-1)electric field:high discharge energy density(W_(d)=0.99 J cm^(-3)),huge instantaneous power density(225.3 MW cm^(-3)),and ultra-fast discharge rate(T_(0.9)≤15.8 ns).The prepared glass-ceramic is expected to be a new type of lead-free multifunctional photoelectric material for temperature sensors and transparent electronic devices.展开更多
基金y the National Natural Science Foundation of China(Grant No.32102466)the Major Scientific Innovation Project of Shandong Province(Grant No.2022CXGC020708).
文摘Atmospheric CO_(2)concentration is elevated globally,which has“CO_(2)fertilization effects”and potentially improves plant photosynthesis,yield,and productivity.Despite the beneficial effect of CO_(2)fertilization being modulated by vapor pressure deficit(VPD),the underlying mechanism is highly uncertain.In the present study,the potential roles of hormones in determining CO_(2)fertilization effects under contrasting high and low VPD conditions were investigated by integrated physiological and transcriptomic analyses.Beneficial CO_(2)fertilization effects were offset under high VPD conditions and were constrained by plant water stress and photosynthetic CO_(2)utilization.High VPD induced a large passive water driving force,which disrupted the water balance and consequently caused plant water deficit.Leaf water potential,turgor pressure,and hydraulic conductance declined under high VPD stress.The physiological evidence combined with transcriptomic analyses demonstrated that abscisic acid(ABA)and jasmonic acid(JA)potentially acted as drought-signaling molecules in response to high VPD stress.Increased foliar ABA and JA content triggered stomatal closure to prevent excessive water loss under high VPD stress,which simultaneously increased the diffusion resistance for CO_(2)uptake from atmosphere to leaf intercellular space.High VPD also significantly increased mesophyll resistance for CO_(2)transport from stomatal cavity to fixation site inside chloroplast.The chloroplast“sink”CO_(2)availability was constrained by stomatal and mesophyll resistance under high VPD stress,despite the atmospheric“source”CO_(2)concentration being elevated.Thus,ABA-and JA-mediated drought-resistant mechanisms potentially modified the beneficial effect of CO_(2)fertilization on photosynthesis,plant growth,and yield productivity.This study provides valuable information for improving the utilization efficiency of CO_(2)fertilization and a better understanding of the physiological processes.
文摘The sambong (Blumea balsamifera (L.) DC.) leaf was investigated by applying frozen section and thin section technology, and observed through optical microscope. The results showed that the sambong leaf was firstly originated nearby the apical bud at the stem tip. The first leaf grows fast, that the mitosis happens frequently and the cytoplasm manufacture rapidly. The cells in the first few leaves have not yet differentiated into the spongy parenchyma and palisade parenchyma. In the mature leaf, the spongy parenchyma and palisade parenchyma were fully developed. The epidermal hairs were firstly developed on the abaxial side of the first leaf.
文摘The plant growth regulator diethyl aminoethyl hexanoate (DA-6) has proved highly effective on micropropagation of the medicinal plant purple coneflower (Echinacea purpurea (L.) Moench), however, sharp variation of the effects existed among explants in the same treatment, making the application of DA-6 in micropropagation difficult. In order to clarify factors that influencing the treating results of DA-6, explants with different biomass dosage were prepared and inoculated onto medium supplemented with different concentrations of DA-6. It was found that among the three kinds of biomass dosage explants, the lowest biomass explants required the lowest concentration of DA-6, and the highest biomass explants required the highest concentration of DA-6 for the best results on adventitious buds regeneration. Similar results were obtained when regenerated buds of three different biomass dosages were cultured. It could be concluded from the above experimental results that for achieving better DA-6 application results, the concentration of DA-6 should be determined not only by the types but also by the biomass dosage of the explants. The present finding might help to improve the micropropagation efficiency in E. purpurea, and might be applicable for other species
文摘Immature leaves and stems, which were about one to three centimeters nearby the stem tips, of Blumea balsamifera (L.) DC. (BB) and Blumea laciniata (Roxb.) DC. (BL) were cut into sections under ?18?C with a frozen section machine, and observed under an optical microscope. Results show that the most significant difference is that the BB has only one kind of glandular trichomes, while the BL has two. The glandular trichomes found on BB terms were all short glandular hairs (SGH), which were not longer than 100 μm. On BL stems, besides the SGH, the long glandular hairs (LGH), which were longer than 200 μm, were also found. By the factors pointed out in present study, the BB and BL and be distinguished from each other.
文摘Anthersisolated from tetraploid purple coneflowerplants were cultured in vitro. The highest callus induction rate was obtained when the medium was consisted of N6 basal elements, 4% sucrose, 0.5 mg?L?1 BA, and 0.10 mg?L?1 NAA. Various morphogenesis such as globular, heart-shape, torpedo-shapeand final state embryos as well asvarious texture calluses around were observed. Out of 110 plantlets regenerated, 104 were confirmed as diploid and the rest were as tetraploid. Plants of one diploid offspring strain presented aspecialcharacter in pot: unlike the original tetraploid plants, it grown tubular, bisexual ray florets. The results obtained in the present studies indicated that although the tetraploid purple coneflower plants produced only diploid microspores, the recovery of some useful mutants through in vitro anther cultures might be reasonably expected.
文摘Mannitol or sorbitol was added into the Murashige and Skoog (MS) medium contain-ing certain concentrations of 6-Benzyladenine (BA) which was used to induce adventi-tious buds of Echinacea purpurea L. Results showed that the induced adventitious buds growing from medium added with 15 g·L-1 mannitol or sorbitol of the same con-centration were more consistent in height. The regeneration rates in MS medium containing 0.2 mg·L-1 BA and 15 g·L-1 mannitol were increased, while in MS medium containing 0.2 and 0.5 mg·L-1 BA, and 15 g·L-1 sorbitol, the regeneration rates were suppressed. On the other hand, genotype of explants and the concentration of BA in-fluenced the incidence of hyperhydricity, and the hyperhydricity of regenerated buds was more severe when the petiole explants were inoculated on medium with 15 g·L-1 mannitol or 15 g·L-1 sorbitol. The present study offers new possibility to the production of uniform plantlets for commercial cultivation in this important medicinal plant.
基金Supported by Hainan Province Basic and Applied Basic Research Program(Natural Science)High-level Talents(No.2019RC318)Nanfeng Special Phase III:Investigation and Protection of Cultivated Land and Fishery Water Resources(NFZX2021)the Central Public-interest Scientific Institution Basal Research Fund for Chinese Academy of Tropical Agricultural Sciences(No.1630032022022)。
文摘[Objectives]This study was conducted to clarify the differences of volatile components in fresh fruit of Morinda citrifolia L.from different origins.[Methods]The method of HS-SPME-GC/MS detection was used to determine the volatile chemical components in fresh fruit of M.citrifolia.[Results]52,52 and 45 volatile components were identified from the fresh fruit of M.citrifolia from Xisha,Wanning and Haikou,respectively.Among them,the number and content of the identified esters were relatively high,mainly methyl caprylate,ethyl caprylate,4-pentenyl caproate,3-methylbuten-2-enyl caprylate,methyl caproate,and ethyl caproate.There were also fatty acids,alcohols,phenols,ketones,aldehydes and other substances.There were 33 common ingredients in the fruit from the three origins,mainly including caprylic acid,caproic acid,capric acid,methyl caprylate,ethyl caprylate,4-pentenyl caproate,3-methylbutene-2-enyl caprylate,methyl caproate,ethyl caproate,methyl caprate and hexyl caproate.[Conclusions]The types and contents of volatile components in fresh fruit of M.citrifolia from different origins were significantly different.
基金supported by the State Grid Science and Technology Project (No. 5455HT160004)
文摘In order to meet the pressing demand for wide-area communication required by the Global Energy Interconnection(GEI),accelerating the construction of satellite-terrestrial Integra怕d networks that can achieve network extension and seamless global coverage has become the focus of power communication tech no logy development.In this study,we propose a satellite-terrestrial integrated network model that can support interconnection and interoperation on the IP layer between the satellite system and the怕rrestrial segment of the existing power communication system.First,the composition and function of the satellite-terrestrial collaborative network are explained.Then,the IP-based protocol stack is described,and a typical applicati on experime nt is con ducted to illustrate the particular process of this protocol stack.Fin ally,a use case of IP interconn ection that depends on GEO satellite communication is detailed.The experime ntal study has showed that the satellite-terrestrial collaborative network can efficiently support various IP applications for the GEI.
基金Supported by National Natural Science Foundation of China(81403035)Central Public-interest Scientific Institution Basal Research Fund for Chinese Academy of Tropical Agricultural Sciences(1630032019004)Central Public-interest Scientific Institution Basal Research Fund for Chinese Academy of Tropical Agricultural Sciences(1630032020002).
文摘[Objectives]This study was conducted to investigate the effects of magnesium on the yield of Blumea balsamifera(L.)DC.and the accumulation of primary metabolites that affect yield of the medicinal material.[Methods]The annual seedlings of B.balsamifera were selected as experimental materials.The treatment concentrations of magnesium(Mg)were set as 0,1.5,15 and 150 mg/ml supplied by MgSO4·7H2O.The yield of the medicinal material was measured dynamically.And the content of total sugar was determined by 3,5-dinitrosalicylic acid colorimetry;the content of crude protein was determined by the Kjeldahl method;the ash content was determined by the high-temperature burning method;the crude fat content was determined with a crude fat instrument;and the crude fiber content was determined by the acid-base washing and weighing method.[Results]Mg significantly increased the yield of B.balsamifera medicinal material,especially 15 mg/ml Mg.It was found that in September,October and November,1.5 mg/ml and 15 mg/ml Mg significantly increased the contents of primary metabolites including total sugar,ash,crude protein,crude fat and crude fiber,and 150 mg/ml of Mg increased the accumulation of total sugar,ash,crude protein and crude fiber to different degrees,but had certain inhibitory effect on the accumulation of crude fat.In December,the application of Mg inhibited the accumulation of total sugar,ash and crude protein to different degrees,but significantly promoted the accumulation of crude fat and fiber.[Conclusions]This study provides a theoretical basis for clarifying the effects of different concentrations of magnesium on plant growth.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11805128,11875042,and 11505114)the Shanghai Project for Construction of Top Disciplines,China(Grant No.USST-SYSBIO)。
文摘An extreme event may lead to serious disaster to a complex system.In an extreme event series there exist generally non-trivial patterns covering different time scales.Investigations on extreme events are currently based upon statistics,where the patterns are merged into averages.In this paper from extreme event series we constructed extreme value series and extreme interval series.And the visibility graph is then adopted to display the patterns formed by the increases/decreases of extreme value or interval faster/slower than the linear ones.For the fractional Brownian motions,the properties for the constructed networks are the persistence,threshold,and event-type-independent,e.g.,the degree distributions decay exponentially with almost identical speeds,the nodes cluster into modular structures with large and similar modularity degrees,and each specific network has a perfect hierarchical structure.For the volatilities of four stock markets(NSDQ,SZI,FTSE100,and HSI),the properties for the former three's networks are threshold-and market-independent.Comparing with the factional Brownian motions,their degree distributions decay exponentially but with slower speeds,their modularity behaviors are significant but with smaller modularity degrees.The fourth market behaves similar qualitatively but different quantitatively with the three markets.Interestingly,all the transition frequency networks share an identical backbone composed of nine edges and the linked graphlets.The universal behaviors give us a framework to describe extreme events from the viewpoint of network.
基金the Fundamental Scientific Research Funds for Chinese Academy of Tropical Agricultural Sciences-Tropical Crops Genetic Resources Institute[The Evaluation and Mechanism Research for the Treatment of Ainaxiang(Herba Blumeae Balsamiferae)Oil on Skin Burns Based on Cytokines,No.#1630032014016]the Natural Science Fund of Hainan Province[the Evaluation and Mechanism Research of Ainaxiang(Herba Blumeae Balsamiferae)Oil on Healingand Repairing of Skin Wounds,No.#312022]the Natural Science Fund of China(Study on Variety Classification of"Nalong"and It's Ethanopharmacology of Li in Hainan,No.#81374065)
文摘OBJECTIVE: To assess the effectiveness of violateoil from Blumea Balsamifera(L.) DC. leaves(BB oil)on wound healing in mice.METHODS: Undiluted BB oil and its diluted solutions with olive oil to 1/5 and 1/10 to yield BB oil1/5and BB oil1/10 were applied to the wounded skin before wound healing conditions were assessed by healing rate, histopathology, and contents of collagen, hydroxyproline, and Neuropeptide Substance P(SP). All above results were compared with the efficacies of the control, pure olive oil, basic fibroblast growth factor(BFGF), and cream of Jing Wan Hong(JWH).RESULTS: BB oil1/5and BB oil1/10 improved wound contraction and closure. Histopathology study further confirmed a desirable histological organization of wound tissues. BB oil1/5and BB oil1/10 reduced the number of inflammatory cells, increased wound-healing rates, and significantly increased the hydroxyproline content. Both BB oil1/5and BB oil1/10 improved formation of collagen, and reduced the frequency of fibroblasts. Moreover, BB oil1/5and BB oil1/10 markedly promoted SP expression. However, undiluted BB oil may induce skin thickening and hardening, inhibite collagen synthesis and delay complete skin wound healing.CONCLUSION: The BB oil1/5and BB oil1/10 promoted capillary regeneration, blood circulation, collagen deposition, granular tissue formation, epithelial deposition, and wound contraction. The mechanism underlying the action might be related to induction of SP secretion, and the proliferation and differentiation of mesenchymal cells.
基金The authors gratefully acknowledge the financial support from the National Natural Science Foundation of China (No. 91534103)the PetroChina Innovation Foundation (No. 2017D-5007-0204)+1 种基金the 111 Project of the Ministry of Education of China (No. B08021)Fundamental Research Funds for the Central Universities of China.
文摘The versatile catechol unit of polydopamine (PDA) endows this molecule with a broad ranging adhesive properties and reducibility.We prepared free-standing PDA particles by a simple self-polymerization and these particles served as both an effective reductant and scaffold for a hybrid catalyst.The raspberrylike nanocomposites featured a high density of AuNPs uniformly deposited on PDA particles (PDA@Au).This system was prepared in-situ with assistance from the active catechol and amine groups of the PDA particles.To quantify the effect of the PDA carriers,we studied the catalytic activity of the PDA and PDA@Au particles.The PDA particles showed a pronounced charge-dependent catalytic activity for reduction of cationic methylene blue,negatively-charged 4-nitrophenolate,and zwitterionic rhodamine B in the presence of borohydride,whereas PDA@AuNPs showed catalytic activity with a less pronounced charge-dependence of the catalytic efficiency of the AuNPs.The PDA particles served as a redox mediator and adsorbent accelerator in degradation of the dyes owing to its unique chemical structure.
基金supported by the National Natural Science Foundation of China (No. 21873052)the Natural Science Foundation of Zhejiang Province (No. LQ20B030004)the Ningbo Natural Science Foundation (No. 202003N4079)。
文摘Introduction of iodosylarnes into biomimetic nonheme chemistry has made great achievement on identification of the subtle metal-oxygen reaction intermediates. However, after more than three decades of experimental and theoretical efforts the nature of the metal-iodosylarene adducts and the related dichotomous one-oxidant/multiple-oxident controversy have remained a matter of speculation. Herein, we report a theoretical study of the structure-activity relationship of the noted iron(Ⅲ)-iodsylarene complex,FeⅢ(Ph IO)(OTf)3(1), in oxygenation of cyclohexene. The calculated results revealed that 1 behaves like a chameleon by adapting its roles as a 2 e-oxidant or an oxygen donor, as a response to the regioselective attack of the C–H bond and the C=C bond. The oxidative C–H bond activation by 1 was found, for the first time, to proceed via a novel hydride transfer process to form a cyclohexene carbonium intermediate,such non-rebound step triggers the Ritter reaction to uptake an acetonitrile molecule to form the amide product, or proceeds with the rebound of the hydroxyl group return to the solvent cage to form the hydroxylated product. While in the C=C bond activation, 1 is a normal oxygen donor and shows two-state reactivity to present the epoxide product via a direct oxygen atom transfer mechanism. These mechanistic findings fit and explain the famous Valentine’s experiments and enrich the non-rebound scenario in bioinorganic chemistry.
基金This work was financially supported by the National Natural Science Foundation of China(No.61865003)Project of Guangxi Key Laboratory of Information Materials(No.211009-Z).
文摘In order to meet the needs of new materials gradually developing towards miniaturization,integration,and light weight,multifunctional BaNb_(2)O_(6):Yb^(3+)/Er^(3+)/Tm^(3+)transparent glass-ceramics were success-fully prepared by melt quenching and controllable crystallization.Its structure,luminescence,and en-ergy transmission were studied.Using the opposite temperature dependence of the Tm^(3+)emission band and the corresponding large energy level gap,a maximum relative sensitivity of 2.3%K^(-1)based on thermal coupling levels(TCLs)is obtained in a wide temperature range(298-673 K).The multi-ratio optical thermometry based on TCLs and non-TCLs is successfully realized by using the different emission bands of double emission centers,which makes it possible for self-reference optical temperature measurement modes.In addition,the transparent glass-ceramic exhibits excellent electrical properties under 700 kV cm^(-1)electric field:high discharge energy density(W_(d)=0.99 J cm^(-3)),huge instantaneous power density(225.3 MW cm^(-3)),and ultra-fast discharge rate(T_(0.9)≤15.8 ns).The prepared glass-ceramic is expected to be a new type of lead-free multifunctional photoelectric material for temperature sensors and transparent electronic devices.