＇ Ji2055A＇ is a superior sterile line sorghum bred by Institute of Crop Resources, Jilin Academy of Agricultural Sciences. It has a growing season of 112 days and a plant height of 70 cm. With a stable sterility rat...＇ Ji2055A＇ is a superior sterile line sorghum bred by Institute of Crop Resources, Jilin Academy of Agricultural Sciences. It has a growing season of 112 days and a plant height of 70 cm. With a stable sterility rate of 100%, ＇ Ji2055A＇ has a stable male sterility and highly viable stignms. Selfing won＇t lead to seeds, This sterile line is strongly resistant to drought and lodging in addition to resistance to leaf spot and head smut. Generally, it has a yield of 3 000 -4 000 kg/hm2 and the hybrid seed yield is between 4 000 - 5 000 kg/hm2, with a high combining ability. There are six varieties approved by the state and the province, as well as another eight new combines under regional testing. The obtained hybrids are strongly resistant, widely adaptable with a great potential to increase yield, ＇ Ji2055A＇ has promoted the breeding and production of spring early maturing sorghum in China.展开更多
Saline water electrolysis is an appealing strategy for hydrogen production,attracting more attention in recent years.NiFe-based electrodes exhibit promise as catalysts for saline water electrolysis.Nevertheless,they s...Saline water electrolysis is an appealing strategy for hydrogen production,attracting more attention in recent years.NiFe-based electrodes exhibit promise as catalysts for saline water electrolysis.Nevertheless,they suffer from the inferior service life of the oxygen evolution reaction(OER).Herein,we report an oxygen-evolution electrode consisting of a sulfate-modulated nickel-iron hydroxide(NiFeOOH)affording as the catalytic active layer and Fe-Ni_(3)S_(2) as the corrosion-proof layer.The developed electrode only requires overpotentials of 220 and 292 mV to deliver the current density of 10 and 500 mA·cm^(−2),respectively.More importantly,it presents long-term stability exceeding 140 and 100 h in 1 M KOH at high current densities of 500 and 1000 mA·cm^(−2),respectively,as well as 120 h for saline water electrolysis at 100 mA·cm^(−2).Experimental results reveal that the generated sulfate plays an indispensable role in improving stability and corrosion resistance.We assembled and tested an anion exchange membrane electrolyzer with Pt/C and NiFeS/NIF as the cathode and anode,respectively,under industrial conditions.This overall water-splitting electrolyzer achieves an impressive energy conversion efficiency of 75%±0.5%.This report offers fresh insights into the design of stable NiFe-based electrodes,which may further promote its practical applications for saline water electrolysis.展开更多
Background:The terminal branch orders of plant root systems are increasingly known as an ephemeral module.This concept is crucial to recognize belowground processes.However,it is unknown if root modules still exist af...Background:The terminal branch orders of plant root systems are increasingly known as an ephemeral module.This concept is crucial to recognize belowground processes.However,it is unknown if root modules still exist after they die?Methods:The decomposition patterns of the first five root orders were observed for 3 years using a branch-order classification,a litter-bag method and sequential sampling in a common subalpine tree species(Picea asperata)of southwestern China.Results:Two root modules were observed during the 3-year incubation.Among the first five branch orders,the first three order roots exhibited temporal patterns of mass loss,nutrients and stoichiometry distinct from their woody mother roots throughout the experimental period.This study,for the first time,reported the decomposition pattern of each individual root order and found a similar decomposition dynamic among ephemeral root branches in a forest tree species.Conclusions:Results from this study suggest that root modules may also exist after death,while more data are needed for confirmation.The findings may further advance our understanding of architecture-associated functional heterogeneity in the fine-root system and also improve our ability to predict belowground processes.展开更多
Repairing osteoporotic bone defects is still a major clinical challenge.Recent studies have revealed that immune response is also essential in osteogenesis.The intrinsic inflammatory response of the host,especially th...Repairing osteoporotic bone defects is still a major clinical challenge.Recent studies have revealed that immune response is also essential in osteogenesis.The intrinsic inflammatory response of the host,especially the M1/M2 polarization status and inflammatory secretory function of macrophages,can directly affect osteogenic differentiation.Therefore,in this study,an electrospun naringin-loaded microspheres/sucrose acetate isobutyrate(Ng-m-SAIB)system was constructed to investigate its effect on the polarization of macrophage and osteoporotic bone defects.The results of both in vitro and in vivo experiments showed that Ng-m-SAIB had good biocompatibility and could promote the polarization of macrophage toward M2,thereby forming a favorable microenvironment for osteogenesis.The animal experiments also showed that Ng-m-SAIB could promote the osteogenesis of critical size defects in the skull of the osteoporotic model mouse(the senescence-accelerated mouse-strain P6).Together,these results collectively suggested that Ng-m-SAIB might be a promising biomaterial to treat osteoporotic bone defects with favorable osteo-immunomodulatory effects.展开更多
The patient is a 37-year-old male with a right anterior tibial mass for more than one year and a left anterior tibial mass for more than one month.There was a history of hyperthyroidism.Histopathology of the lesions s...The patient is a 37-year-old male with a right anterior tibial mass for more than one year and a left anterior tibial mass for more than one month.There was a history of hyperthyroidism.Histopathology of the lesions showed epidermal hyperkeratosis of the skin tissue,thickening of the spinous layer,extensive collagen fibrillation in the superficial dermis and reticular layer,and numerous linear and granular mucoprotein deposits in the lower and middle dermis.Blastocystis hominis was routinely detected in the stool.Diagnosis:1.Pretibial myxedema 2.intestinal parasitosis(Blastocystis hominis infection).展开更多
A new model of dendritic growth and solute distribution of Fe-0.04%C binary alloys was developed, which is based on the sharp interface model of dendritic growth. This innovative model improved the cellular automaton ...A new model of dendritic growth and solute distribution of Fe-0.04%C binary alloys was developed, which is based on the sharp interface model of dendritic growth. This innovative model improved the cellular automaton method, combined with the finite difference method, considered concentration field, temperature field and the shape of molten pool. This model simulated the growth morphologies of single equiaxial crystal, the relationship between tip growth velocity and time, multi-equiaxed crystals’ growth morphologies and solute distribution, the growth of columnar crystals, columnar-to-equiaxed transition after coupling temperature field, and compared with experimental results. The results indicate that crystallographic orientation has certain influence on dendritic morphologies, that the tip growth velocity tends to be stable with the extension of time in the end, that the shape of molten pool influences the growth morphologies of columnar crystals and that the solute mainly concentrates in dendritic roots and among grain boundaries. The simulated results are in accord with experimental results.展开更多
Lithium-ion batteries(LIBs)are widely used in electric vehicles and consumer electronics and require reliable recycling strategies.In this paper,we investigated how an ultrafast carbothermal shock treatment can be use...Lithium-ion batteries(LIBs)are widely used in electric vehicles and consumer electronics and require reliable recycling strategies.In this paper,we investigated how an ultrafast carbothermal shock treatment can be used to convert spent cathodes of LIBs(LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2))into Ni/Ni-Mn-Co-O(N/NMCO)composites with a remarkable electrocatalytic performance toward oxygen evolution,oxygen reduction,and hydrogen evolution reactions.The converted spent cathodes can be employed as cathodes and anodes in an overall water-splitting system,and they displayed a low overpotential of 1.61 V and remarkable stability at different current densities.Moreover,N/NMCO electrodes can be used as cathodes in rechargeable Zn-air batteries,which displayed long-term stability(>30 h),high specific capacity(781 mA h g^(-1))and peak power density(137 mW cm^(-2)),as well as a small charge/discharge voltage gap of 0.71 V.Thus,our study offers a“waste-to-treasure”strategy for the regeneration of spent cathodes of LIBs and their applications in other advanced energy storage and conversion technologies.展开更多
The mixing of raw materials in a rotary drum bioreactor is important for advanced solid-state fermentation technology.However,the shape,size,and other properties of pulverized sweet sorghum stalk particles are more co...The mixing of raw materials in a rotary drum bioreactor is important for advanced solid-state fermentation technology.However,the shape,size,and other properties of pulverized sweet sorghum stalk particles are more complicated than those of the spherical particles.In this study,a soft rod-shaped discrete particle model was established and verified to simulate the mixing behavior of sweet sorghum stalk particles in a rotary drum bioreactor.We were inspired by the particle shape and established a rod-shaped particle model by investigating the influence of the shape(length-diameter ratio)and size(diameter)on the particle packing(stack height and bed porosity).We used orthogonal simulations and extremum difference analysis to determine the main factors,optimum level,and groups of other parameters.Based on calibrated parameters,twelve sets of simulations of radial mixing in the drum were performed,and the results were compared with experiments conducted under identical operating conditions.The average relative error between the simulation and the experiment was 10.95%,which indicates that they agreed well and that the simulation could predict the mixing process well.展开更多
In this paper, we study the M/M/1 queue with working vacations and vacation interruptions. The working vacation is introduced recently, during which the server can still provide service on the original ongoing work at...In this paper, we study the M/M/1 queue with working vacations and vacation interruptions. The working vacation is introduced recently, during which the server can still provide service on the original ongoing work at a lower rate. Meanwhile, we introduce a new policy：, the server can come back from the vacation to the normal working level once some indices of the system, such as the number of customers, achieve a certain value in the vacation period. The server may come back from the vacation without completing the vacation. Such policy is called vacation interruption. We connect the above mentioned two policies and assume that if there are customers in the system after a service completion during the vacation period, the server will come back to the normal working level. In terms of the quasi birth and death process and matrix-geometric solution method, we obtain the distributions and the stochastic decomposition structures for the number of customers and the waiting time and provide some indices of systems.展开更多
Growth-regulating factors(GRFs)are important regulators of plant development and growth,but their possible roles in xylem development in woody plants remain unclear.Here,we report that Populus alba×Papulus glandu...Growth-regulating factors(GRFs)are important regulators of plant development and growth,but their possible roles in xylem development in woody plants remain unclear.Here,we report that Populus alba×Papulus glandulosa PagGRF12a negatively regulates xylem development in poplar.PagGRF12a is expressed in vascular tissues.Compared to non-transgenic control plants,transgenic poplar plants overexpressing PagGRF12a exhibited reduced xylem width and plants with repressed expression of PagGRF12a exhibited increased xylem width.Xylem NAC domain 1(XND1)encodes a NAC domain transcription factor that regulates xylem development and transcriptional analyses revealed that PagXND1a is highly upregulated in PagGRF12a-overexpressing plants and downregulated in PagGRF12a-suppressed plants,indicating that PagGRF12a may regulate xylem development through PagXND1a.Transient transcriptional assays and chromatin immunoprecipitation-polymerase chain reaction assays confirmed that PagGRF12a directly upregulates PagXND1a.In addition,PagGRF12a interacts with the GRF-Interacting Factor(GIF)PagGIF1b,and this interaction enhances the effects of PagGRF12a on PagXND1a.Our results indicate that PagGRF12a inhibits xylem development by upregulating the expression of PagXND1a.展开更多
Based on a new perspective in coordinating with the traditional"N-1"criteria and system risk,a real-time electricity market model is presented,in which the system risk is employed to model the system’s over...Based on a new perspective in coordinating with the traditional"N-1"criteria and system risk,a real-time electricity market model is presented,in which the system risk is employed to model the system’s overall security level.This new model is called the risk-based security-constrained economic dispatch(RB-SCED).Relative to the securityconstrained economic dispatch(SCED)used in the power industry today,the RB-SCED finds more secure and economic operating conditions.It does this by obtaining solutions that achieve a better balance between post-contingency flows on individual branches and the overall system risk.The method exploits the fact that,in a SCED solution,some postcontingency branch flows which exceed their limits impose little risk while other post-contingency branch flows which are within their limits impose significant risk.The RB-SCED softens constraints for the former and hardens constraints for the latter,thus achieving simultaneous improvement in both security and economy.In this work,the basic concept and the mathematical formulation of the RB-SCED model are systematically described.Experimental results on a 9-bus system and the ISO New England actual system have demonstrated the advantages of RB-SCED over SCED.展开更多
The low frequency oscillation characteristics of East China Power Grid after commissioning of the first ultra-high voltage alternating current(UHVAC)project-the Huai-Hu UHVAC project are studied.Several low frequency ...The low frequency oscillation characteristics of East China Power Grid after commissioning of the first ultra-high voltage alternating current(UHVAC)project-the Huai-Hu UHVAC project are studied.Several low frequency oscillation cases occurred in East China Power Grid in the past few years are reviewed and summarized.Based on the analysis of the different typical operation modes,the main low frequency oscillation modes in East China Power Grid in the early stages of development of ultra-high voltage(UHV)are summarized,and the impacts of the significant power grid maintenance on low frequency oscillation characteristics are analyzed.Besides,the oscillation mode of UHV generators to East China Power Grid is researched,and the importance of the power system stabilizator(PSS)is emphasized.Furthermore,the comparative analysis between the time domain and the frequency domain is carried out,and the influences of the governing system on low frequency oscillation characteristics are revealed.Finally,both the focus and the direction of low frequency oscillation research are presented.展开更多
Bacteria play an important role in the formation of primary Common Bile Duct(CBD)stones.However,the composition and function of the microbiota of bile duct in patients with primary CBD stones remained to be explored.W...Bacteria play an important role in the formation of primary Common Bile Duct(CBD)stones.However,the composition and function of the microbiota of bile duct in patients with primary CBD stones remained to be explored.We utilized the 16S rRNA gene high-throughput sequencing technology to analyze the microbial diversity and community composition of biliary and duodenal microbiota in 15 patients with primary CBD stones and 4 patients without biliary tract diseases.Alpha diversity analysis showed that the microbiota richness was similar in bile and intestinal fluid;Beta diversity analysis showed that there were differences in the composition between biliary microbiota and the duodenal microbiota,but the abundance of the main groups showed similarities.The composition of the biliary microbiota from gallstone patients was more complex,as was the duodenal microbiota.Proteobacteria and Firmicutes were the dominant bacteria at phylum level,accounting for at least 75%of the total reads in each subgroup.Pseudomonas and EscherichiaShigella were the major genus among subgroups,but Escherichia-Shigella had increased abundance in duodenal microbiota with primary choledocholithiasis,which may play an important role in stone formation.It is noteworthy that Clostridiumsensu_stricto,Lachnospiraceae_UCG-008,Butyrivibrio and Roseburia which could produce short chain fatty acids(SCFAs),were significantly decreased in biliary microbiota with primary CBD stones(p<0.05).Our study provided new insights into the compositional of normal biliary microbiota.The micro-ecology of biliary and duodenal in patients with stones is complex and closely related,and there is a potential for dysbacteriosis.The decrease in abundance of certain major acid-producing bacteria affects the health of the biliary tract and thus leads to the formation of stones.展开更多
A soft-sphere discrete cohesive powder model was used to simulate the transverse mixing of particles in a rotary drum. Using this model, the effect of cohesion strength and baffle length was investigated. Mixing time ...A soft-sphere discrete cohesive powder model was used to simulate the transverse mixing of particles in a rotary drum. Using this model, the effect of cohesion strength and baffle length was investigated. Mixing time （tR） and mixing entropy were used to characterize the mixing behavior. The results showed that increasing particle cohesiveness increases tR. Baffles enhanced transverse mixing, especially for high- cohesive particles. Moreover, the baffle length played a significant role on mixing. An optimized length of 0.50 （L/R） enhances transverse mixing for high-cohesive particles, Further increases in baffle length only decreases the mixing rate by impeding the surface flow layer. In contrast to high-cohesive particles, low-cohesive particles needed much shorter baffles.A soft-sphere discrete cohesive powder model was used to simulate the transverse mixing of particles in a rotary drum. Using this model, the effect of cohesion strength and baffle length was investigated. Mixing time （tR） and mixing entropy were used to characterize the mixing behavior. The results showed that increasing particle cohesiveness increases tR. Baffles enhanced transverse mixing, especially for high- cohesive particles. Moreover, the baffle length played a significant role on mixing. An optimized length of 0.50 （L/R） enhances transverse mixing for high-cohesive particles. Further increases in baffle length only decreases the mixing rate by impeding the surface flow layer. In contrast to high-cohesive particles, low-cohesive particles needed much shorter baffles.展开更多
基金Supported by Special Fund for the Industrial Technology System Construction of Modern Agriculture(CARS-06-01-03)
文摘＇ Ji2055A＇ is a superior sterile line sorghum bred by Institute of Crop Resources, Jilin Academy of Agricultural Sciences. It has a growing season of 112 days and a plant height of 70 cm. With a stable sterility rate of 100%, ＇ Ji2055A＇ has a stable male sterility and highly viable stignms. Selfing won＇t lead to seeds, This sterile line is strongly resistant to drought and lodging in addition to resistance to leaf spot and head smut. Generally, it has a yield of 3 000 -4 000 kg/hm2 and the hybrid seed yield is between 4 000 - 5 000 kg/hm2, with a high combining ability. There are six varieties approved by the state and the province, as well as another eight new combines under regional testing. The obtained hybrids are strongly resistant, widely adaptable with a great potential to increase yield, ＇ Ji2055A＇ has promoted the breeding and production of spring early maturing sorghum in China.
基金supported by the Key research and development program of Hainan province(No.ZDYF2022GXJS006)the National Natural Science Foundation of China(Nos.52231008,52201009,52122107,and 52301013)+5 种基金International Science and Technology Cooperation Program of Hainan Province(No.GHYF2023007)the Hainan Provincial Natural Science Foundation of China(No.223RC401)the Education Department of Hainan Province(Nos.Hnky2024ZD-2 and Hnky2023ZD-2)Starting Research Funds of the Hainan University of China(Nos.KYQD(ZR)-21105 and KYQD(ZR)-23090)Collaborative Innovation Center of Marine Science and Technology,Hainan University(Nos.XTCX2022HYC18 and XTCX2022HYC22)the Scientific and Technological Project of Yunnan Precious Metals Laboratory(No.YPML-2023050268).
文摘Saline water electrolysis is an appealing strategy for hydrogen production,attracting more attention in recent years.NiFe-based electrodes exhibit promise as catalysts for saline water electrolysis.Nevertheless,they suffer from the inferior service life of the oxygen evolution reaction(OER).Herein,we report an oxygen-evolution electrode consisting of a sulfate-modulated nickel-iron hydroxide(NiFeOOH)affording as the catalytic active layer and Fe-Ni_(3)S_(2) as the corrosion-proof layer.The developed electrode only requires overpotentials of 220 and 292 mV to deliver the current density of 10 and 500 mA·cm^(−2),respectively.More importantly,it presents long-term stability exceeding 140 and 100 h in 1 M KOH at high current densities of 500 and 1000 mA·cm^(−2),respectively,as well as 120 h for saline water electrolysis at 100 mA·cm^(−2).Experimental results reveal that the generated sulfate plays an indispensable role in improving stability and corrosion resistance.We assembled and tested an anion exchange membrane electrolyzer with Pt/C and NiFeS/NIF as the cathode and anode,respectively,under industrial conditions.This overall water-splitting electrolyzer achieves an impressive energy conversion efficiency of 75%±0.5%.This report offers fresh insights into the design of stable NiFe-based electrodes,which may further promote its practical applications for saline water electrolysis.
基金funded by the National Natural Science Foundation of China(Nos.32071745,31870602,31800519 and 31901295)Program of Sichuan Excellent Youth Sci-Tech Foundation(No.2020JDJQ0052)the National Key Research and Development Program of China(Nos.2016YFC0502505and 2017YFC0505003)。
文摘Background:The terminal branch orders of plant root systems are increasingly known as an ephemeral module.This concept is crucial to recognize belowground processes.However,it is unknown if root modules still exist after they die?Methods:The decomposition patterns of the first five root orders were observed for 3 years using a branch-order classification,a litter-bag method and sequential sampling in a common subalpine tree species(Picea asperata)of southwestern China.Results:Two root modules were observed during the 3-year incubation.Among the first five branch orders,the first three order roots exhibited temporal patterns of mass loss,nutrients and stoichiometry distinct from their woody mother roots throughout the experimental period.This study,for the first time,reported the decomposition pattern of each individual root order and found a similar decomposition dynamic among ephemeral root branches in a forest tree species.Conclusions:Results from this study suggest that root modules may also exist after death,while more data are needed for confirmation.The findings may further advance our understanding of architecture-associated functional heterogeneity in the fine-root system and also improve our ability to predict belowground processes.
基金support from the National Natural Science Foundation of China(No.81970914).
文摘Repairing osteoporotic bone defects is still a major clinical challenge.Recent studies have revealed that immune response is also essential in osteogenesis.The intrinsic inflammatory response of the host,especially the M1/M2 polarization status and inflammatory secretory function of macrophages,can directly affect osteogenic differentiation.Therefore,in this study,an electrospun naringin-loaded microspheres/sucrose acetate isobutyrate(Ng-m-SAIB)system was constructed to investigate its effect on the polarization of macrophage and osteoporotic bone defects.The results of both in vitro and in vivo experiments showed that Ng-m-SAIB had good biocompatibility and could promote the polarization of macrophage toward M2,thereby forming a favorable microenvironment for osteogenesis.The animal experiments also showed that Ng-m-SAIB could promote the osteogenesis of critical size defects in the skull of the osteoporotic model mouse(the senescence-accelerated mouse-strain P6).Together,these results collectively suggested that Ng-m-SAIB might be a promising biomaterial to treat osteoporotic bone defects with favorable osteo-immunomodulatory effects.
文摘The patient is a 37-year-old male with a right anterior tibial mass for more than one year and a left anterior tibial mass for more than one month.There was a history of hyperthyroidism.Histopathology of the lesions showed epidermal hyperkeratosis of the skin tissue,thickening of the spinous layer,extensive collagen fibrillation in the superficial dermis and reticular layer,and numerous linear and granular mucoprotein deposits in the lower and middle dermis.Blastocystis hominis was routinely detected in the stool.Diagnosis:1.Pretibial myxedema 2.intestinal parasitosis(Blastocystis hominis infection).
文摘A new model of dendritic growth and solute distribution of Fe-0.04%C binary alloys was developed, which is based on the sharp interface model of dendritic growth. This innovative model improved the cellular automaton method, combined with the finite difference method, considered concentration field, temperature field and the shape of molten pool. This model simulated the growth morphologies of single equiaxial crystal, the relationship between tip growth velocity and time, multi-equiaxed crystals’ growth morphologies and solute distribution, the growth of columnar crystals, columnar-to-equiaxed transition after coupling temperature field, and compared with experimental results. The results indicate that crystallographic orientation has certain influence on dendritic morphologies, that the tip growth velocity tends to be stable with the extension of time in the end, that the shape of molten pool influences the growth morphologies of columnar crystals and that the solute mainly concentrates in dendritic roots and among grain boundaries. The simulated results are in accord with experimental results.
基金supported by the National Natural Science Foundation of China(52177220)Hong Kong Scholar Program(XJ2020001)the State Key Laboratory of Electrical Insulation and Power Equipment of Xi’an University(EIPE21203)。
文摘Lithium-ion batteries(LIBs)are widely used in electric vehicles and consumer electronics and require reliable recycling strategies.In this paper,we investigated how an ultrafast carbothermal shock treatment can be used to convert spent cathodes of LIBs(LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2))into Ni/Ni-Mn-Co-O(N/NMCO)composites with a remarkable electrocatalytic performance toward oxygen evolution,oxygen reduction,and hydrogen evolution reactions.The converted spent cathodes can be employed as cathodes and anodes in an overall water-splitting system,and they displayed a low overpotential of 1.61 V and remarkable stability at different current densities.Moreover,N/NMCO electrodes can be used as cathodes in rechargeable Zn-air batteries,which displayed long-term stability(>30 h),high specific capacity(781 mA h g^(-1))and peak power density(137 mW cm^(-2)),as well as a small charge/discharge voltage gap of 0.71 V.Thus,our study offers a“waste-to-treasure”strategy for the regeneration of spent cathodes of LIBs and their applications in other advanced energy storage and conversion technologies.
基金This work was supported by the National Key R&D Program of China(Grant number 2016YFE0108500).
文摘The mixing of raw materials in a rotary drum bioreactor is important for advanced solid-state fermentation technology.However,the shape,size,and other properties of pulverized sweet sorghum stalk particles are more complicated than those of the spherical particles.In this study,a soft rod-shaped discrete particle model was established and verified to simulate the mixing behavior of sweet sorghum stalk particles in a rotary drum bioreactor.We were inspired by the particle shape and established a rod-shaped particle model by investigating the influence of the shape(length-diameter ratio)and size(diameter)on the particle packing(stack height and bed porosity).We used orthogonal simulations and extremum difference analysis to determine the main factors,optimum level,and groups of other parameters.Based on calibrated parameters,twelve sets of simulations of radial mixing in the drum were performed,and the results were compared with experiments conducted under identical operating conditions.The average relative error between the simulation and the experiment was 10.95%,which indicates that they agreed well and that the simulation could predict the mixing process well.
基金This work was supported in part by National Natural Science Foundation of China under Grant No. 10671170.5. Acknowledgment The authors thank to the anonymous referees for their insightful comments and suggestions, which are very helpful to improve the presentations of the paper.
文摘In this paper, we study the M/M/1 queue with working vacations and vacation interruptions. The working vacation is introduced recently, during which the server can still provide service on the original ongoing work at a lower rate. Meanwhile, we introduce a new policy：, the server can come back from the vacation to the normal working level once some indices of the system, such as the number of customers, achieve a certain value in the vacation period. The server may come back from the vacation without completing the vacation. Such policy is called vacation interruption. We connect the above mentioned two policies and assume that if there are customers in the system after a service completion during the vacation period, the server will come back to the normal working level. In terms of the quasi birth and death process and matrix-geometric solution method, we obtain the distributions and the stochastic decomposition structures for the number of customers and the waiting time and provide some indices of systems.
基金This work was supported by the National Natural ScienceFoundation of China(31570676)the National Key Programon Transgenic Research of China(2018ZX08020-002)+3 种基金the Basic Research Fund of Research Institute of Forest,ChineseAcademy of Forestry(RIF-2014-08)the National Key Re-search and Development Program of China(2016YFD0600103)the National Key Program on Transgenic Re-search of China(2018ZX08020-002)the Ten-thousandTalents Program of China for Meng-Zhu Lu.
文摘Growth-regulating factors(GRFs)are important regulators of plant development and growth,but their possible roles in xylem development in woody plants remain unclear.Here,we report that Populus alba×Papulus glandulosa PagGRF12a negatively regulates xylem development in poplar.PagGRF12a is expressed in vascular tissues.Compared to non-transgenic control plants,transgenic poplar plants overexpressing PagGRF12a exhibited reduced xylem width and plants with repressed expression of PagGRF12a exhibited increased xylem width.Xylem NAC domain 1(XND1)encodes a NAC domain transcription factor that regulates xylem development and transcriptional analyses revealed that PagXND1a is highly upregulated in PagGRF12a-overexpressing plants and downregulated in PagGRF12a-suppressed plants,indicating that PagGRF12a may regulate xylem development through PagXND1a.Transient transcriptional assays and chromatin immunoprecipitation-polymerase chain reaction assays confirmed that PagGRF12a directly upregulates PagXND1a.In addition,PagGRF12a interacts with the GRF-Interacting Factor(GIF)PagGIF1b,and this interaction enhances the effects of PagGRF12a on PagXND1a.Our results indicate that PagGRF12a inhibits xylem development by upregulating the expression of PagXND1a.
基金This work is jointly supported by National High Technology Research and Development Program of China(863 Program)(No.2011AA05A105)a key project from Zhejiang Electric Power Corporation.
文摘Based on a new perspective in coordinating with the traditional"N-1"criteria and system risk,a real-time electricity market model is presented,in which the system risk is employed to model the system’s overall security level.This new model is called the risk-based security-constrained economic dispatch(RB-SCED).Relative to the securityconstrained economic dispatch(SCED)used in the power industry today,the RB-SCED finds more secure and economic operating conditions.It does this by obtaining solutions that achieve a better balance between post-contingency flows on individual branches and the overall system risk.The method exploits the fact that,in a SCED solution,some postcontingency branch flows which exceed their limits impose little risk while other post-contingency branch flows which are within their limits impose significant risk.The RB-SCED softens constraints for the former and hardens constraints for the latter,thus achieving simultaneous improvement in both security and economy.In this work,the basic concept and the mathematical formulation of the RB-SCED model are systematically described.Experimental results on a 9-bus system and the ISO New England actual system have demonstrated the advantages of RB-SCED over SCED.
文摘The low frequency oscillation characteristics of East China Power Grid after commissioning of the first ultra-high voltage alternating current(UHVAC)project-the Huai-Hu UHVAC project are studied.Several low frequency oscillation cases occurred in East China Power Grid in the past few years are reviewed and summarized.Based on the analysis of the different typical operation modes,the main low frequency oscillation modes in East China Power Grid in the early stages of development of ultra-high voltage(UHV)are summarized,and the impacts of the significant power grid maintenance on low frequency oscillation characteristics are analyzed.Besides,the oscillation mode of UHV generators to East China Power Grid is researched,and the importance of the power system stabilizator(PSS)is emphasized.Furthermore,the comparative analysis between the time domain and the frequency domain is carried out,and the influences of the governing system on low frequency oscillation characteristics are revealed.Finally,both the focus and the direction of low frequency oscillation research are presented.
文摘Bacteria play an important role in the formation of primary Common Bile Duct(CBD)stones.However,the composition and function of the microbiota of bile duct in patients with primary CBD stones remained to be explored.We utilized the 16S rRNA gene high-throughput sequencing technology to analyze the microbial diversity and community composition of biliary and duodenal microbiota in 15 patients with primary CBD stones and 4 patients without biliary tract diseases.Alpha diversity analysis showed that the microbiota richness was similar in bile and intestinal fluid;Beta diversity analysis showed that there were differences in the composition between biliary microbiota and the duodenal microbiota,but the abundance of the main groups showed similarities.The composition of the biliary microbiota from gallstone patients was more complex,as was the duodenal microbiota.Proteobacteria and Firmicutes were the dominant bacteria at phylum level,accounting for at least 75%of the total reads in each subgroup.Pseudomonas and EscherichiaShigella were the major genus among subgroups,but Escherichia-Shigella had increased abundance in duodenal microbiota with primary choledocholithiasis,which may play an important role in stone formation.It is noteworthy that Clostridiumsensu_stricto,Lachnospiraceae_UCG-008,Butyrivibrio and Roseburia which could produce short chain fatty acids(SCFAs),were significantly decreased in biliary microbiota with primary CBD stones(p<0.05).Our study provided new insights into the compositional of normal biliary microbiota.The micro-ecology of biliary and duodenal in patients with stones is complex and closely related,and there is a potential for dysbacteriosis.The decrease in abundance of certain major acid-producing bacteria affects the health of the biliary tract and thus leads to the formation of stones.
文摘A soft-sphere discrete cohesive powder model was used to simulate the transverse mixing of particles in a rotary drum. Using this model, the effect of cohesion strength and baffle length was investigated. Mixing time （tR） and mixing entropy were used to characterize the mixing behavior. The results showed that increasing particle cohesiveness increases tR. Baffles enhanced transverse mixing, especially for high- cohesive particles. Moreover, the baffle length played a significant role on mixing. An optimized length of 0.50 （L/R） enhances transverse mixing for high-cohesive particles, Further increases in baffle length only decreases the mixing rate by impeding the surface flow layer. In contrast to high-cohesive particles, low-cohesive particles needed much shorter baffles.A soft-sphere discrete cohesive powder model was used to simulate the transverse mixing of particles in a rotary drum. Using this model, the effect of cohesion strength and baffle length was investigated. Mixing time （tR） and mixing entropy were used to characterize the mixing behavior. The results showed that increasing particle cohesiveness increases tR. Baffles enhanced transverse mixing, especially for high- cohesive particles. Moreover, the baffle length played a significant role on mixing. An optimized length of 0.50 （L/R） enhances transverse mixing for high-cohesive particles. Further increases in baffle length only decreases the mixing rate by impeding the surface flow layer. In contrast to high-cohesive particles, low-cohesive particles needed much shorter baffles.
